17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_KEX_MASK 0x000F
110 #define SSH2_PKTCTX_PUBLICKEY 0x0010
111 #define SSH2_PKTCTX_PASSWORD 0x0020
112 #define SSH2_PKTCTX_KBDINTER 0x0040
113 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
115 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
131 static const char *const ssh2_disconnect_reasons[] = {
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
150 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
155 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
158 * Various remote-bug flags.
160 #define BUG_CHOKES_ON_SSH1_IGNORE 1
161 #define BUG_SSH2_HMAC 2
162 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
163 #define BUG_CHOKES_ON_RSA 8
164 #define BUG_SSH2_RSA_PADDING 16
165 #define BUG_SSH2_DERIVEKEY 32
166 #define BUG_SSH2_REKEY 64
167 #define BUG_SSH2_PK_SESSIONID 128
169 #define translate(x) if (type == x) return #x
170 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
171 static char *ssh1_pkt_type(int type)
173 translate(SSH1_MSG_DISCONNECT);
174 translate(SSH1_SMSG_PUBLIC_KEY);
175 translate(SSH1_CMSG_SESSION_KEY);
176 translate(SSH1_CMSG_USER);
177 translate(SSH1_CMSG_AUTH_RSA);
178 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
179 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
180 translate(SSH1_CMSG_AUTH_PASSWORD);
181 translate(SSH1_CMSG_REQUEST_PTY);
182 translate(SSH1_CMSG_WINDOW_SIZE);
183 translate(SSH1_CMSG_EXEC_SHELL);
184 translate(SSH1_CMSG_EXEC_CMD);
185 translate(SSH1_SMSG_SUCCESS);
186 translate(SSH1_SMSG_FAILURE);
187 translate(SSH1_CMSG_STDIN_DATA);
188 translate(SSH1_SMSG_STDOUT_DATA);
189 translate(SSH1_SMSG_STDERR_DATA);
190 translate(SSH1_CMSG_EOF);
191 translate(SSH1_SMSG_EXIT_STATUS);
192 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
193 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
194 translate(SSH1_MSG_CHANNEL_DATA);
195 translate(SSH1_MSG_CHANNEL_CLOSE);
196 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
197 translate(SSH1_SMSG_X11_OPEN);
198 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
199 translate(SSH1_MSG_PORT_OPEN);
200 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
201 translate(SSH1_SMSG_AGENT_OPEN);
202 translate(SSH1_MSG_IGNORE);
203 translate(SSH1_CMSG_EXIT_CONFIRMATION);
204 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
205 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
206 translate(SSH1_MSG_DEBUG);
207 translate(SSH1_CMSG_REQUEST_COMPRESSION);
208 translate(SSH1_CMSG_AUTH_TIS);
209 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
210 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
211 translate(SSH1_CMSG_AUTH_CCARD);
212 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
213 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
216 static char *ssh2_pkt_type(int pkt_ctx, int type)
218 translate(SSH2_MSG_DISCONNECT);
219 translate(SSH2_MSG_IGNORE);
220 translate(SSH2_MSG_UNIMPLEMENTED);
221 translate(SSH2_MSG_DEBUG);
222 translate(SSH2_MSG_SERVICE_REQUEST);
223 translate(SSH2_MSG_SERVICE_ACCEPT);
224 translate(SSH2_MSG_KEXINIT);
225 translate(SSH2_MSG_NEWKEYS);
226 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP);
227 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP);
228 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
229 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
230 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
231 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
232 translate(SSH2_MSG_USERAUTH_REQUEST);
233 translate(SSH2_MSG_USERAUTH_FAILURE);
234 translate(SSH2_MSG_USERAUTH_SUCCESS);
235 translate(SSH2_MSG_USERAUTH_BANNER);
236 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
237 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
238 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
239 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
240 translate(SSH2_MSG_GLOBAL_REQUEST);
241 translate(SSH2_MSG_REQUEST_SUCCESS);
242 translate(SSH2_MSG_REQUEST_FAILURE);
243 translate(SSH2_MSG_CHANNEL_OPEN);
244 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
245 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
246 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
247 translate(SSH2_MSG_CHANNEL_DATA);
248 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
249 translate(SSH2_MSG_CHANNEL_EOF);
250 translate(SSH2_MSG_CHANNEL_CLOSE);
251 translate(SSH2_MSG_CHANNEL_REQUEST);
252 translate(SSH2_MSG_CHANNEL_SUCCESS);
253 translate(SSH2_MSG_CHANNEL_FAILURE);
259 #define GET_32BIT(cp) \
260 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
261 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
262 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
263 ((unsigned long)(unsigned char)(cp)[3]))
265 #define PUT_32BIT(cp, value) { \
266 (cp)[0] = (unsigned char)((value) >> 24); \
267 (cp)[1] = (unsigned char)((value) >> 16); \
268 (cp)[2] = (unsigned char)((value) >> 8); \
269 (cp)[3] = (unsigned char)(value); }
271 /* Enumeration values for fields in SSH-1 packets */
273 PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM,
274 /* These values are for communicating relevant semantics of
275 * fields to the packet logging code. */
276 PKTT_OTHER, PKTT_PASSWORD, PKTT_DATA
280 * Coroutine mechanics for the sillier bits of the code. If these
281 * macros look impenetrable to you, you might find it helpful to
284 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
286 * which explains the theory behind these macros.
288 * In particular, if you are getting `case expression not constant'
289 * errors when building with MS Visual Studio, this is because MS's
290 * Edit and Continue debugging feature causes their compiler to
291 * violate ANSI C. To disable Edit and Continue debugging:
293 * - right-click ssh.c in the FileView
295 * - select the C/C++ tab and the General category
296 * - under `Debug info:', select anything _other_ than `Program
297 * Database for Edit and Continue'.
299 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
302 if (!ssh->t) ssh->t = snew(struct t); \
304 #define crFinish(z) } *crLine = 0; return (z); }
305 #define crFinishV } *crLine = 0; return; }
306 #define crReturn(z) \
308 *crLine =__LINE__; return (z); case __LINE__:;\
312 *crLine=__LINE__; return; case __LINE__:;\
314 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
315 #define crStopV do{ *crLine = 0; return; }while(0)
316 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
317 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
319 typedef struct ssh_tag *Ssh;
322 static struct Packet *ssh2_pkt_init(int pkt_type);
323 static void ssh2_pkt_addbool(struct Packet *, unsigned char value);
324 static void ssh2_pkt_adduint32(struct Packet *, unsigned long value);
325 static void ssh2_pkt_addstring_start(struct Packet *);
326 static void ssh2_pkt_addstring_str(struct Packet *, char *data);
327 static void ssh2_pkt_addstring_data(struct Packet *, char *data, int len);
328 static void ssh2_pkt_addstring(struct Packet *, char *data);
329 static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
330 static void ssh2_pkt_addmp(struct Packet *, Bignum b);
331 static int ssh2_pkt_construct(Ssh, struct Packet *);
332 static void ssh2_pkt_send(Ssh, struct Packet *);
333 static void ssh2_pkt_send_noqueue(Ssh, struct Packet *);
334 static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
335 struct Packet *pktin);
336 static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
337 struct Packet *pktin);
340 * Buffer management constants. There are several of these for
341 * various different purposes:
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH-1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH-2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH-2
360 #define SSH1_BUFFER_LIMIT 32768
361 #define SSH_MAX_BACKLOG 32768
362 #define OUR_V2_WINSIZE 16384
363 #define OUR_V2_MAXPKT 0x4000UL
365 const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
367 static void *nullmac_make_context(void)
371 static void nullmac_free_context(void *handle)
374 static void nullmac_key(void *handle, unsigned char *key)
377 static void nullmac_generate(void *handle, unsigned char *blk, int len,
381 static int nullmac_verify(void *handle, unsigned char *blk, int len,
386 const static struct ssh_mac ssh_mac_none = {
387 nullmac_make_context, nullmac_free_context, nullmac_key,
388 nullmac_generate, nullmac_verify, "none", 0
390 const static struct ssh_mac *macs[] = {
391 &ssh_sha1, &ssh_md5, &ssh_mac_none
393 const static struct ssh_mac *buggymacs[] = {
394 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
397 static void *ssh_comp_none_init(void)
401 static void ssh_comp_none_cleanup(void *handle)
404 static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
405 unsigned char **outblock, int *outlen)
409 static int ssh_comp_none_disable(void *handle)
413 const static struct ssh_compress ssh_comp_none = {
415 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
416 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
417 ssh_comp_none_disable, NULL
419 extern const struct ssh_compress ssh_zlib;
420 const static struct ssh_compress *compressions[] = {
421 &ssh_zlib, &ssh_comp_none
424 enum { /* channel types */
429 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
433 * 2-3-4 tree storing channels.
436 Ssh ssh; /* pointer back to main context */
437 unsigned remoteid, localid;
439 /* True if we opened this channel but server hasn't confirmed. */
442 * In SSH-1, this value contains four bits:
444 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
445 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
447 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
449 * A channel is completely finished with when all four bits are set.
453 struct ssh1_data_channel {
456 struct ssh2_data_channel {
458 unsigned remwindow, remmaxpkt;
463 struct ssh_agent_channel {
464 unsigned char *message;
465 unsigned char msglen[4];
466 unsigned lensofar, totallen;
468 struct ssh_x11_channel {
471 struct ssh_pfd_channel {
478 * 2-3-4 tree storing remote->local port forwardings. SSH-1 and SSH-2
479 * use this structure in different ways, reflecting SSH-2's
480 * altogether saner approach to port forwarding.
482 * In SSH-1, you arrange a remote forwarding by sending the server
483 * the remote port number, and the local destination host:port.
484 * When a connection comes in, the server sends you back that
485 * host:port pair, and you connect to it. This is a ready-made
486 * security hole if you're not on the ball: a malicious server
487 * could send you back _any_ host:port pair, so if you trustingly
488 * connect to the address it gives you then you've just opened the
489 * entire inside of your corporate network just by connecting
490 * through it to a dodgy SSH server. Hence, we must store a list of
491 * host:port pairs we _are_ trying to forward to, and reject a
492 * connection request from the server if it's not in the list.
494 * In SSH-2, each side of the connection minds its own business and
495 * doesn't send unnecessary information to the other. You arrange a
496 * remote forwarding by sending the server just the remote port
497 * number. When a connection comes in, the server tells you which
498 * of its ports was connected to; and _you_ have to remember what
499 * local host:port pair went with that port number.
501 * Hence, in SSH-1 this structure is indexed by destination
502 * host:port pair, whereas in SSH-2 it is indexed by source port.
504 struct ssh_portfwd; /* forward declaration */
506 struct ssh_rportfwd {
507 unsigned sport, dport;
510 struct ssh_portfwd *pfrec;
512 #define free_rportfwd(pf) ( \
513 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
516 * Separately to the rportfwd tree (which is for looking up port
517 * open requests from the server), a tree of _these_ structures is
518 * used to keep track of all the currently open port forwardings,
519 * so that we can reconfigure in mid-session if the user requests
523 enum { DESTROY, KEEP, CREATE } status;
525 unsigned sport, dport;
528 struct ssh_rportfwd *remote;
532 #define free_portfwd(pf) ( \
533 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
534 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
538 long forcepad; /* Force padding to at least this length */
540 unsigned long sequence;
545 long encrypted_len; /* for SSH-2 total-size counting */
548 * State associated with packet logging
552 struct logblank_t *blanks;
555 static void ssh1_protocol(Ssh ssh, void *vin, int inlen,
556 struct Packet *pktin);
557 static void ssh2_protocol(Ssh ssh, void *vin, int inlen,
558 struct Packet *pktin);
559 static void ssh1_protocol_setup(Ssh ssh);
560 static void ssh2_protocol_setup(Ssh ssh);
561 static void ssh_size(void *handle, int width, int height);
562 static void ssh_special(void *handle, Telnet_Special);
563 static int ssh2_try_send(struct ssh_channel *c);
564 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
565 static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
566 static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
567 static int ssh_sendbuffer(void *handle);
568 static int ssh_do_close(Ssh ssh, int notify_exit);
569 static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
570 static int ssh2_pkt_getbool(struct Packet *pkt);
571 static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
572 static void ssh2_timer(void *ctx, long now);
573 static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
574 struct Packet *pktin);
576 struct rdpkt1_state_tag {
577 long len, pad, biglen, to_read;
578 unsigned long realcrc, gotcrc;
582 struct Packet *pktin;
585 struct rdpkt2_state_tag {
586 long len, pad, payload, packetlen, maclen;
589 unsigned long incoming_sequence;
590 struct Packet *pktin;
593 typedef void (*handler_fn_t)(Ssh ssh, struct Packet *pktin);
594 typedef void (*chandler_fn_t)(Ssh ssh, struct Packet *pktin, void *ctx);
596 struct queued_handler;
597 struct queued_handler {
599 chandler_fn_t handler;
601 struct queued_handler *next;
605 const struct plug_function_table *fn;
606 /* the above field _must_ be first in the structure */
608 SHA_State exhash, exhashbase;
615 unsigned char session_key[32];
617 int v1_remote_protoflags;
618 int v1_local_protoflags;
619 int agentfwd_enabled;
622 const struct ssh_cipher *cipher;
625 const struct ssh2_cipher *cscipher, *sccipher;
626 void *cs_cipher_ctx, *sc_cipher_ctx;
627 const struct ssh_mac *csmac, *scmac;
628 void *cs_mac_ctx, *sc_mac_ctx;
629 const struct ssh_compress *cscomp, *sccomp;
630 void *cs_comp_ctx, *sc_comp_ctx;
631 const struct ssh_kex *kex;
632 const struct ssh_signkey *hostkey;
633 unsigned char v2_session_id[20];
639 int echoing, editing;
643 int ospeed, ispeed; /* temporaries */
644 int term_width, term_height;
646 tree234 *channels; /* indexed by local id */
647 struct ssh_channel *mainchan; /* primary session channel */
651 tree234 *rportfwds, *portfwds;
655 SSH_STATE_BEFORE_SIZE,
661 int size_needed, eof_needed;
663 struct Packet **queue;
664 int queuelen, queuesize;
666 unsigned char *deferred_send_data;
667 int deferred_len, deferred_size;
670 * Gross hack: pscp will try to start SFTP but fall back to
671 * scp1 if that fails. This variable is the means by which
672 * scp.c can reach into the SSH code and find out which one it
678 * Used for username and password input.
680 char *userpass_input_buffer;
681 int userpass_input_buflen;
682 int userpass_input_bufpos;
683 int userpass_input_echo;
690 int v1_throttle_count;
693 int v1_stdout_throttling;
694 unsigned long v2_outgoing_sequence;
696 int ssh1_rdpkt_crstate;
697 int ssh2_rdpkt_crstate;
698 int do_ssh_init_crstate;
699 int ssh_gotdata_crstate;
700 int do_ssh1_login_crstate;
701 int do_ssh1_connection_crstate;
702 int do_ssh2_transport_crstate;
703 int do_ssh2_authconn_crstate;
705 void *do_ssh_init_state;
706 void *do_ssh1_login_state;
707 void *do_ssh2_transport_state;
708 void *do_ssh2_authconn_state;
710 struct rdpkt1_state_tag rdpkt1_state;
711 struct rdpkt2_state_tag rdpkt2_state;
713 /* SSH-1 and SSH-2 use this for different things, but both use it */
714 int protocol_initial_phase_done;
716 void (*protocol) (Ssh ssh, void *vin, int inlen,
718 struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
721 * We maintain a full _copy_ of a Config structure here, not
722 * merely a pointer to it. That way, when we're passed a new
723 * one for reconfiguration, we can check the differences and
724 * potentially reconfigure port forwardings etc in mid-session.
729 * Used to transfer data back from async callbacks.
731 void *agent_response;
732 int agent_response_len;
736 * The SSH connection can be set as `frozen', meaning we are
737 * not currently accepting incoming data from the network. This
738 * is slightly more serious than setting the _socket_ as
739 * frozen, because we may already have had data passed to us
740 * from the network which we need to delay processing until
741 * after the freeze is lifted, so we also need a bufchain to
745 bufchain queued_incoming_data;
748 * Dispatch table for packet types that we may have to deal
751 handler_fn_t packet_dispatch[256];
754 * Queues of one-off handler functions for success/failure
755 * indications from a request.
757 struct queued_handler *qhead, *qtail;
760 * This module deals with sending keepalives.
765 * Track incoming and outgoing data sizes and time, for
768 unsigned long incoming_data_size, outgoing_data_size, deferred_data_size;
769 unsigned long max_data_size;
771 long next_rekey, last_rekey;
772 char *deferred_rekey_reason; /* points to STATIC string; don't free */
775 #define logevent(s) logevent(ssh->frontend, s)
777 /* logevent, only printf-formatted. */
778 static void logeventf(Ssh ssh, const char *fmt, ...)
784 buf = dupvprintf(fmt, ap);
790 #define bombout(msg) \
792 char *text = dupprintf msg; \
793 ssh_do_close(ssh, FALSE); \
795 connection_fatal(ssh->frontend, "%s", text); \
799 /* Functions to leave bits out of the SSH packet log file. */
801 static void dont_log_password(Ssh ssh, struct Packet *pkt, int blanktype)
803 if (ssh->cfg.logomitpass)
804 pkt->logmode = blanktype;
807 static void dont_log_data(Ssh ssh, struct Packet *pkt, int blanktype)
809 if (ssh->cfg.logomitdata)
810 pkt->logmode = blanktype;
813 static void end_log_omission(Ssh ssh, struct Packet *pkt)
815 pkt->logmode = PKTLOG_EMIT;
818 static int ssh_channelcmp(void *av, void *bv)
820 struct ssh_channel *a = (struct ssh_channel *) av;
821 struct ssh_channel *b = (struct ssh_channel *) bv;
822 if (a->localid < b->localid)
824 if (a->localid > b->localid)
828 static int ssh_channelfind(void *av, void *bv)
830 unsigned *a = (unsigned *) av;
831 struct ssh_channel *b = (struct ssh_channel *) bv;
839 static int ssh_rportcmp_ssh1(void *av, void *bv)
841 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
842 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
844 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
845 return i < 0 ? -1 : +1;
846 if (a->dport > b->dport)
848 if (a->dport < b->dport)
853 static int ssh_rportcmp_ssh2(void *av, void *bv)
855 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
856 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
858 if (a->sport > b->sport)
860 if (a->sport < b->sport)
866 * Special form of strcmp which can cope with NULL inputs. NULL is
867 * defined to sort before even the empty string.
869 static int nullstrcmp(const char *a, const char *b)
871 if (a == NULL && b == NULL)
880 static int ssh_portcmp(void *av, void *bv)
882 struct ssh_portfwd *a = (struct ssh_portfwd *) av;
883 struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
885 if (a->type > b->type)
887 if (a->type < b->type)
889 if (a->addressfamily > b->addressfamily)
891 if (a->addressfamily < b->addressfamily)
893 if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
894 return i < 0 ? -1 : +1;
895 if (a->sport > b->sport)
897 if (a->sport < b->sport)
899 if (a->type != 'D') {
900 if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
901 return i < 0 ? -1 : +1;
902 if (a->dport > b->dport)
904 if (a->dport < b->dport)
910 static int alloc_channel_id(Ssh ssh)
912 const unsigned CHANNEL_NUMBER_OFFSET = 256;
913 unsigned low, high, mid;
915 struct ssh_channel *c;
918 * First-fit allocation of channel numbers: always pick the
919 * lowest unused one. To do this, binary-search using the
920 * counted B-tree to find the largest channel ID which is in a
921 * contiguous sequence from the beginning. (Precisely
922 * everything in that sequence must have ID equal to its tree
923 * index plus CHANNEL_NUMBER_OFFSET.)
925 tsize = count234(ssh->channels);
929 while (high - low > 1) {
930 mid = (high + low) / 2;
931 c = index234(ssh->channels, mid);
932 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
933 low = mid; /* this one is fine */
935 high = mid; /* this one is past it */
938 * Now low points to either -1, or the tree index of the
939 * largest ID in the initial sequence.
942 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
943 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
945 return low + 1 + CHANNEL_NUMBER_OFFSET;
948 static void c_write(Ssh ssh, const char *buf, int len)
950 if ((flags & FLAG_STDERR)) {
952 for (i = 0; i < len; i++)
954 fputc(buf[i], stderr);
957 from_backend(ssh->frontend, 1, buf, len);
960 static void c_write_untrusted(Ssh ssh, const char *buf, int len)
963 for (i = 0; i < len; i++) {
965 c_write(ssh, "\r\n", 2);
966 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
967 c_write(ssh, buf + i, 1);
971 static void c_write_str(Ssh ssh, const char *buf)
973 c_write(ssh, buf, strlen(buf));
976 static void ssh_free_packet(struct Packet *pkt)
981 static struct Packet *ssh_new_packet(void)
983 struct Packet *pkt = snew(struct Packet);
987 pkt->logmode = PKTLOG_EMIT;
995 * Collect incoming data in the incoming packet buffer.
996 * Decipher and verify the packet when it is completely read.
997 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
998 * Update the *data and *datalen variables.
999 * Return a Packet structure when a packet is completed.
1001 static struct Packet *ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
1003 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
1005 crBegin(ssh->ssh1_rdpkt_crstate);
1007 st->pktin = ssh_new_packet();
1009 st->pktin->type = 0;
1010 st->pktin->length = 0;
1012 for (st->i = st->len = 0; st->i < 4; st->i++) {
1013 while ((*datalen) == 0)
1015 st->len = (st->len << 8) + **data;
1016 (*data)++, (*datalen)--;
1019 st->pad = 8 - (st->len % 8);
1020 st->biglen = st->len + st->pad;
1021 st->pktin->length = st->len - 5;
1023 if (st->biglen < 0) {
1024 bombout(("Extremely large packet length from server suggests"
1025 " data stream corruption"));
1026 ssh_free_packet(st->pktin);
1030 st->pktin->maxlen = st->biglen;
1031 st->pktin->data = snewn(st->biglen + APIEXTRA, unsigned char);
1033 st->to_read = st->biglen;
1034 st->p = st->pktin->data;
1035 while (st->to_read > 0) {
1036 st->chunk = st->to_read;
1037 while ((*datalen) == 0)
1039 if (st->chunk > (*datalen))
1040 st->chunk = (*datalen);
1041 memcpy(st->p, *data, st->chunk);
1043 *datalen -= st->chunk;
1045 st->to_read -= st->chunk;
1048 if (ssh->cipher && detect_attack(ssh->crcda_ctx, st->pktin->data,
1049 st->biglen, NULL)) {
1050 bombout(("Network attack (CRC compensation) detected!"));
1051 ssh_free_packet(st->pktin);
1056 ssh->cipher->decrypt(ssh->v1_cipher_ctx, st->pktin->data, st->biglen);
1058 st->realcrc = crc32_compute(st->pktin->data, st->biglen - 4);
1059 st->gotcrc = GET_32BIT(st->pktin->data + st->biglen - 4);
1060 if (st->gotcrc != st->realcrc) {
1061 bombout(("Incorrect CRC received on packet"));
1062 ssh_free_packet(st->pktin);
1066 st->pktin->body = st->pktin->data + st->pad + 1;
1067 st->pktin->savedpos = 0;
1069 if (ssh->v1_compressing) {
1070 unsigned char *decompblk;
1072 if (!zlib_decompress_block(ssh->sc_comp_ctx,
1073 st->pktin->body - 1, st->pktin->length + 1,
1074 &decompblk, &decomplen)) {
1075 bombout(("Zlib decompression encountered invalid data"));
1076 ssh_free_packet(st->pktin);
1080 if (st->pktin->maxlen < st->pad + decomplen) {
1081 st->pktin->maxlen = st->pad + decomplen;
1082 st->pktin->data = sresize(st->pktin->data,
1083 st->pktin->maxlen + APIEXTRA,
1085 st->pktin->body = st->pktin->data + st->pad + 1;
1088 memcpy(st->pktin->body - 1, decompblk, decomplen);
1090 st->pktin->length = decomplen - 1;
1093 st->pktin->type = st->pktin->body[-1];
1096 * Log incoming packet, possibly omitting sensitive fields.
1100 struct logblank_t blank;
1101 if (ssh->cfg.logomitdata) {
1102 int do_blank = FALSE, blank_prefix = 0;
1103 /* "Session data" packets - omit the data field */
1104 if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
1105 (st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
1106 do_blank = TRUE; blank_prefix = 0;
1107 } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
1108 do_blank = TRUE; blank_prefix = 4;
1111 blank.offset = blank_prefix;
1112 blank.len = st->pktin->length;
1113 blank.type = PKTLOG_OMIT;
1117 log_packet(ssh->logctx,
1118 PKT_INCOMING, st->pktin->type,
1119 ssh1_pkt_type(st->pktin->type),
1120 st->pktin->body, st->pktin->length,
1124 crFinish(st->pktin);
1127 static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
1129 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
1131 crBegin(ssh->ssh2_rdpkt_crstate);
1133 st->pktin = ssh_new_packet();
1135 st->pktin->type = 0;
1136 st->pktin->length = 0;
1138 st->cipherblk = ssh->sccipher->blksize;
1141 if (st->cipherblk < 8)
1144 st->pktin->data = snewn(st->cipherblk + APIEXTRA, unsigned char);
1147 * Acquire and decrypt the first block of the packet. This will
1148 * contain the length and padding details.
1150 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
1151 while ((*datalen) == 0)
1153 st->pktin->data[st->i] = *(*data)++;
1158 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1159 st->pktin->data, st->cipherblk);
1162 * Now get the length and padding figures.
1164 st->len = GET_32BIT(st->pktin->data);
1165 st->pad = st->pktin->data[4];
1168 * _Completely_ silly lengths should be stomped on before they
1169 * do us any more damage.
1171 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
1172 bombout(("Incoming packet was garbled on decryption"));
1173 ssh_free_packet(st->pktin);
1178 * This enables us to deduce the payload length.
1180 st->payload = st->len - st->pad - 1;
1182 st->pktin->length = st->payload + 5;
1185 * So now we can work out the total packet length.
1187 st->packetlen = st->len + 4;
1188 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
1191 * Allocate memory for the rest of the packet.
1193 st->pktin->maxlen = st->packetlen + st->maclen;
1194 st->pktin->data = sresize(st->pktin->data,
1195 st->pktin->maxlen + APIEXTRA,
1199 * Read and decrypt the remainder of the packet.
1201 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1203 while ((*datalen) == 0)
1205 st->pktin->data[st->i] = *(*data)++;
1208 /* Decrypt everything _except_ the MAC. */
1210 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1211 st->pktin->data + st->cipherblk,
1212 st->packetlen - st->cipherblk);
1214 st->pktin->encrypted_len = st->packetlen;
1220 && !ssh->scmac->verify(ssh->sc_mac_ctx, st->pktin->data, st->len + 4,
1221 st->incoming_sequence)) {
1222 bombout(("Incorrect MAC received on packet"));
1223 ssh_free_packet(st->pktin);
1227 st->pktin->sequence = st->incoming_sequence++;
1230 * Decompress packet payload.
1233 unsigned char *newpayload;
1236 ssh->sccomp->decompress(ssh->sc_comp_ctx,
1237 st->pktin->data + 5, st->pktin->length - 5,
1238 &newpayload, &newlen)) {
1239 if (st->pktin->maxlen < newlen + 5) {
1240 st->pktin->maxlen = newlen + 5;
1241 st->pktin->data = sresize(st->pktin->data,
1242 st->pktin->maxlen + APIEXTRA,
1245 st->pktin->length = 5 + newlen;
1246 memcpy(st->pktin->data + 5, newpayload, newlen);
1251 st->pktin->savedpos = 6;
1252 st->pktin->body = st->pktin->data;
1253 st->pktin->type = st->pktin->data[5];
1256 * Log incoming packet, possibly omitting sensitive fields.
1260 struct logblank_t blank;
1261 if (ssh->cfg.logomitdata) {
1262 int do_blank = FALSE, blank_prefix = 0;
1263 /* "Session data" packets - omit the data field */
1264 if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
1265 do_blank = TRUE; blank_prefix = 4;
1266 } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
1267 do_blank = TRUE; blank_prefix = 8;
1270 blank.offset = blank_prefix;
1271 blank.len = (st->pktin->length-6) - blank_prefix;
1272 blank.type = PKTLOG_OMIT;
1276 log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
1277 ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
1278 st->pktin->data+6, st->pktin->length-6,
1282 crFinish(st->pktin);
1285 static void ssh1_pktout_size(struct Packet *pkt, int len)
1289 len += 5; /* type and CRC */
1290 pad = 8 - (len % 8);
1293 pkt->length = len - 5;
1294 if (pkt->maxlen < biglen) {
1295 pkt->maxlen = biglen;
1296 pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
1298 pkt->body = pkt->data + 4 + pad + 1;
1301 static struct Packet *s_wrpkt_start(int type, int len)
1303 struct Packet *pkt = ssh_new_packet();
1304 ssh1_pktout_size(pkt, len);
1306 /* Initialise log omission state */
1312 static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
1318 * XXX various versions of SC (including 8.8.4) screw up the
1319 * register allocation in this function and use the same register
1320 * (D6) for len and as a temporary, with predictable results. The
1321 * following sledgehammer prevents this.
1327 pkt->body[-1] = pkt->type;
1330 log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
1331 ssh1_pkt_type(pkt->type),
1332 pkt->body, pkt->length,
1333 pkt->nblanks, pkt->blanks);
1334 sfree(pkt->blanks); pkt->blanks = NULL;
1337 if (ssh->v1_compressing) {
1338 unsigned char *compblk;
1340 zlib_compress_block(ssh->cs_comp_ctx,
1341 pkt->body - 1, pkt->length + 1,
1342 &compblk, &complen);
1343 ssh1_pktout_size(pkt, complen - 1);
1344 memcpy(pkt->body - 1, compblk, complen);
1348 len = pkt->length + 5; /* type and CRC */
1349 pad = 8 - (len % 8);
1352 for (i = 0; i < pad; i++)
1353 pkt->data[i + 4] = random_byte();
1354 crc = crc32_compute(pkt->data + 4, biglen - 4);
1355 PUT_32BIT(pkt->data + biglen, crc);
1356 PUT_32BIT(pkt->data, len);
1359 ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
1364 static void s_wrpkt(Ssh ssh, struct Packet *pkt)
1367 len = s_wrpkt_prepare(ssh, pkt);
1368 backlog = sk_write(ssh->s, (char *)pkt->data, len);
1369 if (backlog > SSH_MAX_BACKLOG)
1370 ssh_throttle_all(ssh, 1, backlog);
1373 static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
1376 len = s_wrpkt_prepare(ssh, pkt);
1377 if (ssh->deferred_len + len > ssh->deferred_size) {
1378 ssh->deferred_size = ssh->deferred_len + len + 128;
1379 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1383 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
1384 ssh->deferred_len += len;
1388 * Construct a packet with the specified contents.
1390 static struct Packet *construct_packet(Ssh ssh, int pkttype,
1391 va_list ap1, va_list ap2)
1393 unsigned char *p, *argp, argchar;
1394 unsigned long argint;
1395 int pktlen, argtype, arglen;
1400 while ((argtype = va_arg(ap1, int)) != PKT_END) {
1403 (void) va_arg(ap1, int);
1407 (void) va_arg(ap1, int);
1411 (void) va_arg(ap1, unsigned char *);
1412 arglen = va_arg(ap1, int);
1416 argp = va_arg(ap1, unsigned char *);
1417 arglen = strlen((char *)argp);
1418 pktlen += 4 + arglen;
1421 bn = va_arg(ap1, Bignum);
1422 pktlen += ssh1_bignum_length(bn);
1427 /* ignore this pass */
1434 pkt = s_wrpkt_start(pkttype, pktlen);
1437 while ((argtype = va_arg(ap2, int)) != PKT_END) {
1438 int offset = p - pkt->body, len = 0;
1440 /* Actual fields in the packet */
1442 argint = va_arg(ap2, int);
1443 PUT_32BIT(p, argint);
1447 argchar = (unsigned char) va_arg(ap2, int);
1452 argp = va_arg(ap2, unsigned char *);
1453 arglen = va_arg(ap2, int);
1454 memcpy(p, argp, arglen);
1458 argp = va_arg(ap2, unsigned char *);
1459 arglen = strlen((char *)argp);
1460 PUT_32BIT(p, arglen);
1461 memcpy(p + 4, argp, arglen);
1465 bn = va_arg(ap2, Bignum);
1466 len = ssh1_write_bignum(p, bn);
1468 /* Tokens for modifications to packet logging */
1470 dont_log_password(ssh, pkt, PKTLOG_BLANK);
1473 dont_log_data(ssh, pkt, PKTLOG_OMIT);
1476 end_log_omission(ssh, pkt);
1480 /* Deal with logfile omission, if required. */
1481 if (len && (pkt->logmode != PKTLOG_EMIT)) {
1483 pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
1485 pkt->blanks[pkt->nblanks-1].offset = offset;
1486 pkt->blanks[pkt->nblanks-1].len = len;
1487 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1494 static void send_packet(Ssh ssh, int pkttype, ...)
1498 va_start(ap1, pkttype);
1499 va_start(ap2, pkttype);
1500 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1504 ssh_free_packet(pkt);
1507 static void defer_packet(Ssh ssh, int pkttype, ...)
1511 va_start(ap1, pkttype);
1512 va_start(ap2, pkttype);
1513 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1516 s_wrpkt_defer(ssh, pkt);
1517 ssh_free_packet(pkt);
1520 static int ssh_versioncmp(char *a, char *b)
1523 unsigned long av, bv;
1525 av = strtoul(a, &ae, 10);
1526 bv = strtoul(b, &be, 10);
1528 return (av < bv ? -1 : +1);
1533 av = strtoul(ae, &ae, 10);
1534 bv = strtoul(be, &be, 10);
1536 return (av < bv ? -1 : +1);
1541 * Utility routines for putting an SSH-protocol `string' and
1542 * `uint32' into a SHA state.
1545 static void sha_string(SHA_State * s, void *str, int len)
1547 unsigned char lenblk[4];
1548 PUT_32BIT(lenblk, len);
1549 SHA_Bytes(s, lenblk, 4);
1550 SHA_Bytes(s, str, len);
1553 static void sha_uint32(SHA_State * s, unsigned i)
1555 unsigned char intblk[4];
1556 PUT_32BIT(intblk, i);
1557 SHA_Bytes(s, intblk, 4);
1561 * SSH-2 packet construction functions.
1563 static void ssh2_pkt_ensure(struct Packet *pkt, int length)
1565 if (pkt->maxlen < length) {
1566 pkt->maxlen = length + 256;
1567 pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
1570 static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
1572 if (pkt->logmode != PKTLOG_EMIT) {
1574 pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
1575 pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
1576 pkt->blanks[pkt->nblanks-1].len = len;
1577 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1580 ssh2_pkt_ensure(pkt, pkt->length);
1581 memcpy(pkt->data + pkt->length - len, data, len);
1583 static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
1585 ssh2_pkt_adddata(pkt, &byte, 1);
1587 static struct Packet *ssh2_pkt_init(int pkt_type)
1589 struct Packet *pkt = ssh_new_packet();
1592 ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
1595 static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
1597 ssh2_pkt_adddata(pkt, &value, 1);
1599 static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
1602 PUT_32BIT(x, value);
1603 ssh2_pkt_adddata(pkt, x, 4);
1605 static void ssh2_pkt_addstring_start(struct Packet *pkt)
1607 ssh2_pkt_adduint32(pkt, 0);
1608 pkt->savedpos = pkt->length;
1610 static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
1612 ssh2_pkt_adddata(pkt, data, strlen(data));
1613 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
1615 static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
1617 ssh2_pkt_adddata(pkt, data, len);
1618 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
1620 static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
1622 ssh2_pkt_addstring_start(pkt);
1623 ssh2_pkt_addstring_str(pkt, data);
1625 static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
1628 int i, n = (bignum_bitcount(b) + 7) / 8;
1629 p = snewn(n + 1, unsigned char);
1631 fatalbox("out of memory");
1633 for (i = 1; i <= n; i++)
1634 p[i] = bignum_byte(b, n - i);
1636 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1638 memmove(p, p + i, n + 1 - i);
1642 static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
1646 p = ssh2_mpint_fmt(b, &len);
1647 ssh2_pkt_addstring_start(pkt);
1648 ssh2_pkt_addstring_data(pkt, (char *)p, len);
1653 * Construct an SSH-2 final-form packet: compress it, encrypt it,
1654 * put the MAC on it. Final packet, ready to be sent, is stored in
1655 * pkt->data. Total length is returned.
1657 static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
1659 int cipherblk, maclen, padding, i;
1662 log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
1663 ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
1664 pkt->data + 6, pkt->length - 6,
1665 pkt->nblanks, pkt->blanks);
1666 sfree(pkt->blanks); pkt->blanks = NULL;
1670 * Compress packet payload.
1673 unsigned char *newpayload;
1676 ssh->cscomp->compress(ssh->cs_comp_ctx, pkt->data + 5,
1678 &newpayload, &newlen)) {
1680 ssh2_pkt_adddata(pkt, newpayload, newlen);
1686 * Add padding. At least four bytes, and must also bring total
1687 * length (minus MAC) up to a multiple of the block size.
1688 * If pkt->forcepad is set, make sure the packet is at least that size
1691 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
1692 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
1694 if (pkt->length + padding < pkt->forcepad)
1695 padding = pkt->forcepad - pkt->length;
1697 (cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
1698 assert(padding <= 255);
1699 maclen = ssh->csmac ? ssh->csmac->len : 0;
1700 ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
1701 pkt->data[4] = padding;
1702 for (i = 0; i < padding; i++)
1703 pkt->data[pkt->length + i] = random_byte();
1704 PUT_32BIT(pkt->data, pkt->length + padding - 4);
1706 ssh->csmac->generate(ssh->cs_mac_ctx, pkt->data,
1707 pkt->length + padding,
1708 ssh->v2_outgoing_sequence);
1709 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1712 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
1713 pkt->data, pkt->length + padding);
1715 pkt->encrypted_len = pkt->length + padding;
1717 /* Ready-to-send packet starts at pkt->data. We return length. */
1718 return pkt->length + padding + maclen;
1722 * Routines called from the main SSH code to send packets. There
1723 * are quite a few of these, because we have two separate
1724 * mechanisms for delaying the sending of packets:
1726 * - In order to send an IGNORE message and a password message in
1727 * a single fixed-length blob, we require the ability to
1728 * concatenate the encrypted forms of those two packets _into_ a
1729 * single blob and then pass it to our <network.h> transport
1730 * layer in one go. Hence, there's a deferment mechanism which
1731 * works after packet encryption.
1733 * - In order to avoid sending any connection-layer messages
1734 * during repeat key exchange, we have to queue up any such
1735 * outgoing messages _before_ they are encrypted (and in
1736 * particular before they're allocated sequence numbers), and
1737 * then send them once we've finished.
1739 * I call these mechanisms `defer' and `queue' respectively, so as
1740 * to distinguish them reasonably easily.
1742 * The functions send_noqueue() and defer_noqueue() free the packet
1743 * structure they are passed. Every outgoing packet goes through
1744 * precisely one of these functions in its life; packets passed to
1745 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1746 * these or get queued, and then when the queue is later emptied
1747 * the packets are all passed to defer_noqueue().
1751 * Send an SSH-2 packet immediately, without queuing or deferring.
1753 static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
1757 len = ssh2_pkt_construct(ssh, pkt);
1758 backlog = sk_write(ssh->s, (char *)pkt->data, len);
1759 if (backlog > SSH_MAX_BACKLOG)
1760 ssh_throttle_all(ssh, 1, backlog);
1762 ssh->outgoing_data_size += pkt->encrypted_len;
1763 if (!ssh->kex_in_progress &&
1764 ssh->max_data_size != 0 &&
1765 ssh->outgoing_data_size > ssh->max_data_size)
1766 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
1768 ssh_free_packet(pkt);
1772 * Defer an SSH-2 packet.
1774 static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
1776 int len = ssh2_pkt_construct(ssh, pkt);
1777 if (ssh->deferred_len + len > ssh->deferred_size) {
1778 ssh->deferred_size = ssh->deferred_len + len + 128;
1779 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1783 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
1784 ssh->deferred_len += len;
1785 ssh->deferred_data_size += pkt->encrypted_len;
1786 ssh_free_packet(pkt);
1790 * Queue an SSH-2 packet.
1792 static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
1794 assert(ssh->queueing);
1796 if (ssh->queuelen >= ssh->queuesize) {
1797 ssh->queuesize = ssh->queuelen + 32;
1798 ssh->queue = sresize(ssh->queue, ssh->queuesize, struct Packet *);
1801 ssh->queue[ssh->queuelen++] = pkt;
1805 * Either queue or send a packet, depending on whether queueing is
1808 static void ssh2_pkt_send(Ssh ssh, struct Packet *pkt)
1811 ssh2_pkt_queue(ssh, pkt);
1813 ssh2_pkt_send_noqueue(ssh, pkt);
1818 * Either queue or defer a packet, depending on whether queueing is
1821 static void ssh2_pkt_defer(Ssh ssh, struct Packet *pkt)
1824 ssh2_pkt_queue(ssh, pkt);
1826 ssh2_pkt_defer_noqueue(ssh, pkt);
1831 * Send the whole deferred data block constructed by
1832 * ssh2_pkt_defer() or SSH-1's defer_packet().
1834 * The expected use of the defer mechanism is that you call
1835 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1836 * not currently queueing, this simply sets up deferred_send_data
1837 * and then sends it. If we _are_ currently queueing, the calls to
1838 * ssh2_pkt_defer() put the deferred packets on to the queue
1839 * instead, and therefore ssh_pkt_defersend() has no deferred data
1840 * to send. Hence, there's no need to make it conditional on
1843 static void ssh_pkt_defersend(Ssh ssh)
1846 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1848 ssh->deferred_len = ssh->deferred_size = 0;
1849 sfree(ssh->deferred_send_data);
1850 ssh->deferred_send_data = NULL;
1851 if (backlog > SSH_MAX_BACKLOG)
1852 ssh_throttle_all(ssh, 1, backlog);
1854 ssh->outgoing_data_size += ssh->deferred_data_size;
1855 if (!ssh->kex_in_progress &&
1856 ssh->max_data_size != 0 &&
1857 ssh->outgoing_data_size > ssh->max_data_size)
1858 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
1859 ssh->deferred_data_size = 0;
1863 * Send all queued SSH-2 packets. We send them by means of
1864 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1865 * packets that needed to be lumped together.
1867 static void ssh2_pkt_queuesend(Ssh ssh)
1871 assert(!ssh->queueing);
1873 for (i = 0; i < ssh->queuelen; i++)
1874 ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
1877 ssh_pkt_defersend(ssh);
1881 void bndebug(char *string, Bignum b)
1885 p = ssh2_mpint_fmt(b, &len);
1886 debug(("%s", string));
1887 for (i = 0; i < len; i++)
1888 debug((" %02x", p[i]));
1894 static void sha_mpint(SHA_State * s, Bignum b)
1898 p = ssh2_mpint_fmt(b, &len);
1899 sha_string(s, p, len);
1904 * Packet decode functions for both SSH-1 and SSH-2.
1906 static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
1908 unsigned long value;
1909 if (pkt->length - pkt->savedpos < 4)
1910 return 0; /* arrgh, no way to decline (FIXME?) */
1911 value = GET_32BIT(pkt->body + pkt->savedpos);
1915 static int ssh2_pkt_getbool(struct Packet *pkt)
1917 unsigned long value;
1918 if (pkt->length - pkt->savedpos < 1)
1919 return 0; /* arrgh, no way to decline (FIXME?) */
1920 value = pkt->body[pkt->savedpos] != 0;
1924 static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length)
1929 if (pkt->length - pkt->savedpos < 4)
1931 len = GET_32BIT(pkt->body + pkt->savedpos);
1936 if (pkt->length - pkt->savedpos < *length)
1938 *p = (char *)(pkt->body + pkt->savedpos);
1939 pkt->savedpos += *length;
1941 static void *ssh_pkt_getdata(struct Packet *pkt, int length)
1943 if (pkt->length - pkt->savedpos < length)
1945 pkt->savedpos += length;
1946 return pkt->body + (pkt->savedpos - length);
1948 static int ssh1_pkt_getrsakey(struct Packet *pkt, struct RSAKey *key,
1949 unsigned char **keystr)
1953 j = makekey(pkt->body + pkt->savedpos,
1954 pkt->length - pkt->savedpos,
1961 assert(pkt->savedpos < pkt->length);
1965 static Bignum ssh1_pkt_getmp(struct Packet *pkt)
1970 j = ssh1_read_bignum(pkt->body + pkt->savedpos,
1971 pkt->length - pkt->savedpos, &b);
1979 static Bignum ssh2_pkt_getmp(struct Packet *pkt)
1985 ssh_pkt_getstring(pkt, &p, &length);
1990 b = bignum_from_bytes((unsigned char *)p, length);
1995 * Helper function to add an SSH-2 signature blob to a packet.
1996 * Expects to be shown the public key blob as well as the signature
1997 * blob. Normally works just like ssh2_pkt_addstring, but will
1998 * fiddle with the signature packet if necessary for
1999 * BUG_SSH2_RSA_PADDING.
2001 static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt,
2002 void *pkblob_v, int pkblob_len,
2003 void *sigblob_v, int sigblob_len)
2005 unsigned char *pkblob = (unsigned char *)pkblob_v;
2006 unsigned char *sigblob = (unsigned char *)sigblob_v;
2008 /* dmemdump(pkblob, pkblob_len); */
2009 /* dmemdump(sigblob, sigblob_len); */
2012 * See if this is in fact an ssh-rsa signature and a buggy
2013 * server; otherwise we can just do this the easy way.
2015 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
2016 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
2017 int pos, len, siglen;
2020 * Find the byte length of the modulus.
2023 pos = 4+7; /* skip over "ssh-rsa" */
2024 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
2025 len = GET_32BIT(pkblob+pos); /* find length of modulus */
2026 pos += 4; /* find modulus itself */
2027 while (len > 0 && pkblob[pos] == 0)
2029 /* debug(("modulus length is %d\n", len)); */
2032 * Now find the signature integer.
2034 pos = 4+7; /* skip over "ssh-rsa" */
2035 siglen = GET_32BIT(sigblob+pos);
2036 /* debug(("signature length is %d\n", siglen)); */
2038 if (len != siglen) {
2039 unsigned char newlen[4];
2040 ssh2_pkt_addstring_start(pkt);
2041 ssh2_pkt_addstring_data(pkt, (char *)sigblob, pos);
2042 /* dmemdump(sigblob, pos); */
2043 pos += 4; /* point to start of actual sig */
2044 PUT_32BIT(newlen, len);
2045 ssh2_pkt_addstring_data(pkt, (char *)newlen, 4);
2046 /* dmemdump(newlen, 4); */
2048 while (len-- > siglen) {
2049 ssh2_pkt_addstring_data(pkt, (char *)newlen, 1);
2050 /* dmemdump(newlen, 1); */
2052 ssh2_pkt_addstring_data(pkt, (char *)(sigblob+pos), siglen);
2053 /* dmemdump(sigblob+pos, siglen); */
2057 /* Otherwise fall through and do it the easy way. */
2060 ssh2_pkt_addstring_start(pkt);
2061 ssh2_pkt_addstring_data(pkt, (char *)sigblob, sigblob_len);
2065 * Examine the remote side's version string and compare it against
2066 * a list of known buggy implementations.
2068 static void ssh_detect_bugs(Ssh ssh, char *vstring)
2070 char *imp; /* pointer to implementation part */
2072 imp += strcspn(imp, "-");
2074 imp += strcspn(imp, "-");
2077 ssh->remote_bugs = 0;
2079 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
2080 (ssh->cfg.sshbug_ignore1 == AUTO &&
2081 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
2082 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
2083 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
2084 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
2086 * These versions don't support SSH1_MSG_IGNORE, so we have
2087 * to use a different defence against password length
2090 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
2091 logevent("We believe remote version has SSH-1 ignore bug");
2094 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
2095 (ssh->cfg.sshbug_plainpw1 == AUTO &&
2096 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
2098 * These versions need a plain password sent; they can't
2099 * handle having a null and a random length of data after
2102 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
2103 logevent("We believe remote version needs a plain SSH-1 password");
2106 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
2107 (ssh->cfg.sshbug_rsa1 == AUTO &&
2108 (!strcmp(imp, "Cisco-1.25")))) {
2110 * These versions apparently have no clue whatever about
2111 * RSA authentication and will panic and die if they see
2112 * an AUTH_RSA message.
2114 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
2115 logevent("We believe remote version can't handle SSH-1 RSA authentication");
2118 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
2119 (ssh->cfg.sshbug_hmac2 == AUTO &&
2120 !wc_match("* VShell", imp) &&
2121 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
2122 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
2123 wc_match("2.1 *", imp)))) {
2125 * These versions have the HMAC bug.
2127 ssh->remote_bugs |= BUG_SSH2_HMAC;
2128 logevent("We believe remote version has SSH-2 HMAC bug");
2131 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
2132 (ssh->cfg.sshbug_derivekey2 == AUTO &&
2133 !wc_match("* VShell", imp) &&
2134 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
2136 * These versions have the key-derivation bug (failing to
2137 * include the literal shared secret in the hashes that
2138 * generate the keys).
2140 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
2141 logevent("We believe remote version has SSH-2 key-derivation bug");
2144 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
2145 (ssh->cfg.sshbug_rsapad2 == AUTO &&
2146 (wc_match("OpenSSH_2.[5-9]*", imp) ||
2147 wc_match("OpenSSH_3.[0-2]*", imp)))) {
2149 * These versions have the SSH-2 RSA padding bug.
2151 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
2152 logevent("We believe remote version has SSH-2 RSA padding bug");
2155 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
2156 (ssh->cfg.sshbug_pksessid2 == AUTO &&
2157 wc_match("OpenSSH_2.[0-2]*", imp))) {
2159 * These versions have the SSH-2 session-ID bug in
2160 * public-key authentication.
2162 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
2163 logevent("We believe remote version has SSH-2 public-key-session-ID bug");
2166 if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
2167 (ssh->cfg.sshbug_rekey2 == AUTO &&
2168 (wc_match("OpenSSH_2.[0-4]*", imp) ||
2169 wc_match("OpenSSH_2.5.[0-3]*", imp) ||
2170 wc_match("Sun_SSH_1.0", imp) ||
2171 wc_match("Sun_SSH_1.0.1", imp)))) {
2173 * These versions have the SSH-2 rekey bug.
2175 ssh->remote_bugs |= BUG_SSH2_REKEY;
2176 logevent("We believe remote version has SSH-2 rekey bug");
2181 * The `software version' part of an SSH version string is required
2182 * to contain no spaces or minus signs.
2184 static void ssh_fix_verstring(char *str)
2186 /* Eat "SSH-<protoversion>-". */
2187 assert(*str == 'S'); str++;
2188 assert(*str == 'S'); str++;
2189 assert(*str == 'H'); str++;
2190 assert(*str == '-'); str++;
2191 while (*str && *str != '-') str++;
2192 assert(*str == '-'); str++;
2194 /* Convert minus signs and spaces in the remaining string into
2197 if (*str == '-' || *str == ' ')
2203 static int do_ssh_init(Ssh ssh, unsigned char c)
2205 struct do_ssh_init_state {
2213 crState(do_ssh_init_state);
2215 crBegin(ssh->do_ssh_init_crstate);
2217 /* Search for the string "SSH-" in the input. */
2220 static const int transS[] = { 1, 2, 2, 1 };
2221 static const int transH[] = { 0, 0, 3, 0 };
2222 static const int transminus[] = { 0, 0, 0, -1 };
2224 s->i = transS[s->i];
2226 s->i = transH[s->i];
2228 s->i = transminus[s->i];
2233 crReturn(1); /* get another character */
2237 s->vstring = snewn(s->vstrsize, char);
2238 strcpy(s->vstring, "SSH-");
2242 crReturn(1); /* get another char */
2243 if (s->vslen >= s->vstrsize - 1) {
2245 s->vstring = sresize(s->vstring, s->vstrsize, char);
2247 s->vstring[s->vslen++] = c;
2250 s->version[s->i] = '\0';
2252 } else if (s->i < sizeof(s->version) - 1)
2253 s->version[s->i++] = c;
2254 } else if (c == '\012')
2258 ssh->agentfwd_enabled = FALSE;
2259 ssh->rdpkt2_state.incoming_sequence = 0;
2261 s->vstring[s->vslen] = 0;
2262 s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
2263 logeventf(ssh, "Server version: %s", s->vstring);
2264 ssh_detect_bugs(ssh, s->vstring);
2267 * Decide which SSH protocol version to support.
2270 /* Anything strictly below "2.0" means protocol 1 is supported. */
2271 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
2272 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2273 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
2275 if (ssh->cfg.sshprot == 0 && !s->proto1) {
2276 bombout(("SSH protocol version 1 required by user but not provided by server"));
2279 if (ssh->cfg.sshprot == 3 && !s->proto2) {
2280 bombout(("SSH protocol version 2 required by user but not provided by server"));
2287 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
2289 * Construct a v2 version string.
2291 verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
2295 * Construct a v1 version string.
2297 verstring = dupprintf("SSH-%s-%s\012",
2298 (ssh_versioncmp(s->version, "1.5") <= 0 ?
2299 s->version : "1.5"),
2304 ssh_fix_verstring(verstring);
2306 if (ssh->version == 2) {
2308 * Hash our version string and their version string.
2310 SHA_Init(&ssh->exhashbase);
2311 sha_string(&ssh->exhashbase, verstring,
2312 strcspn(verstring, "\015\012"));
2313 sha_string(&ssh->exhashbase, s->vstring,
2314 strcspn(s->vstring, "\015\012"));
2317 * Initialise SSH-2 protocol.
2319 ssh->protocol = ssh2_protocol;
2320 ssh2_protocol_setup(ssh);
2321 ssh->s_rdpkt = ssh2_rdpkt;
2324 * Initialise SSH-1 protocol.
2326 ssh->protocol = ssh1_protocol;
2327 ssh1_protocol_setup(ssh);
2328 ssh->s_rdpkt = ssh1_rdpkt;
2330 logeventf(ssh, "We claim version: %.*s",
2331 strcspn(verstring, "\015\012"), verstring);
2332 sk_write(ssh->s, verstring, strlen(verstring));
2336 logeventf(ssh, "Using SSH protocol version %d", ssh->version);
2338 update_specials_menu(ssh->frontend);
2339 ssh->state = SSH_STATE_BEFORE_SIZE;
2340 ssh->pinger = pinger_new(&ssh->cfg, &ssh_backend, ssh);
2347 static void ssh_process_incoming_data(Ssh ssh,
2348 unsigned char **data, int *datalen)
2350 struct Packet *pktin = ssh->s_rdpkt(ssh, data, datalen);
2352 ssh->protocol(ssh, NULL, 0, pktin);
2353 ssh_free_packet(pktin);
2357 static void ssh_queue_incoming_data(Ssh ssh,
2358 unsigned char **data, int *datalen)
2360 bufchain_add(&ssh->queued_incoming_data, *data, *datalen);
2365 static void ssh_process_queued_incoming_data(Ssh ssh)
2368 unsigned char *data;
2371 while (!ssh->frozen && bufchain_size(&ssh->queued_incoming_data)) {
2372 bufchain_prefix(&ssh->queued_incoming_data, &vdata, &len);
2376 while (!ssh->frozen && len > 0)
2377 ssh_process_incoming_data(ssh, &data, &len);
2380 bufchain_consume(&ssh->queued_incoming_data, origlen - len);
2384 static void ssh_set_frozen(Ssh ssh, int frozen)
2387 sk_set_frozen(ssh->s, frozen);
2388 ssh->frozen = frozen;
2391 static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
2393 crBegin(ssh->ssh_gotdata_crstate);
2396 * To begin with, feed the characters one by one to the
2397 * protocol initialisation / selection function do_ssh_init().
2398 * When that returns 0, we're done with the initial greeting
2399 * exchange and can move on to packet discipline.
2402 int ret; /* need not be kept across crReturn */
2404 crReturnV; /* more data please */
2405 ret = do_ssh_init(ssh, *data);
2413 * We emerge from that loop when the initial negotiation is
2414 * over and we have selected an s_rdpkt function. Now pass
2415 * everything to s_rdpkt, and then pass the resulting packets
2416 * to the proper protocol handler.
2422 * Process queued data if there is any.
2424 ssh_process_queued_incoming_data(ssh);
2427 while (datalen > 0) {
2429 ssh_queue_incoming_data(ssh, &data, &datalen);
2431 ssh_process_incoming_data(ssh, &data, &datalen);
2433 if (ssh->state == SSH_STATE_CLOSED)
2441 static int ssh_do_close(Ssh ssh, int notify_exit)
2444 struct ssh_channel *c;
2446 ssh->state = SSH_STATE_CLOSED;
2451 notify_remote_exit(ssh->frontend);
2456 * Now we must shut down any port- and X-forwarded channels going
2457 * through this connection.
2459 if (ssh->channels) {
2460 while (NULL != (c = index234(ssh->channels, 0))) {
2463 x11_close(c->u.x11.s);
2466 pfd_close(c->u.pfd.s);
2469 del234(ssh->channels, c); /* moving next one to index 0 */
2470 if (ssh->version == 2)
2471 bufchain_clear(&c->v.v2.outbuffer);
2476 * Go through port-forwardings, and close any associated
2477 * listening sockets.
2479 if (ssh->portfwds) {
2480 struct ssh_portfwd *pf;
2481 while (NULL != (pf = index234(ssh->portfwds, 0))) {
2482 /* Dispose of any listening socket. */
2484 pfd_terminate(pf->local);
2485 del234(ssh->portfwds, pf); /* moving next one to index 0 */
2493 static void ssh_log(Plug plug, int type, SockAddr addr, int port,
2494 const char *error_msg, int error_code)
2496 Ssh ssh = (Ssh) plug;
2497 char addrbuf[256], *msg;
2499 sk_getaddr(addr, addrbuf, lenof(addrbuf));
2502 msg = dupprintf("Connecting to %s port %d", addrbuf, port);
2504 msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
2510 static int ssh_closing(Plug plug, const char *error_msg, int error_code,
2513 Ssh ssh = (Ssh) plug;
2514 int need_notify = ssh_do_close(ssh, FALSE);
2516 if (!error_msg && !ssh->close_expected) {
2517 error_msg = "Server unexpectedly closed network connection";
2521 notify_remote_exit(ssh->frontend);
2524 /* A socket error has occurred. */
2525 logevent(error_msg);
2526 connection_fatal(ssh->frontend, "%s", error_msg);
2528 logevent("Server closed network connection");
2533 static int ssh_receive(Plug plug, int urgent, char *data, int len)
2535 Ssh ssh = (Ssh) plug;
2536 ssh_gotdata(ssh, (unsigned char *)data, len);
2537 if (ssh->state == SSH_STATE_CLOSED) {
2538 ssh_do_close(ssh, TRUE);
2544 static void ssh_sent(Plug plug, int bufsize)
2546 Ssh ssh = (Ssh) plug;
2548 * If the send backlog on the SSH socket itself clears, we
2549 * should unthrottle the whole world if it was throttled.
2551 if (bufsize < SSH_MAX_BACKLOG)
2552 ssh_throttle_all(ssh, 0, bufsize);
2556 * Connect to specified host and port.
2557 * Returns an error message, or NULL on success.
2558 * Also places the canonical host name into `realhost'. It must be
2559 * freed by the caller.
2561 static const char *connect_to_host(Ssh ssh, char *host, int port,
2562 char **realhost, int nodelay, int keepalive)
2564 static const struct plug_function_table fn_table = {
2575 ssh->savedhost = snewn(1 + strlen(host), char);
2576 if (!ssh->savedhost)
2577 fatalbox("Out of memory");
2578 strcpy(ssh->savedhost, host);
2581 port = 22; /* default ssh port */
2582 ssh->savedport = port;
2587 logeventf(ssh, "Looking up host \"%s\"%s", host,
2588 (ssh->cfg.addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
2589 (ssh->cfg.addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : "")));
2590 addr = name_lookup(host, port, realhost, &ssh->cfg,
2591 ssh->cfg.addressfamily);
2592 if ((err = sk_addr_error(addr)) != NULL) {
2600 ssh->fn = &fn_table;
2601 ssh->s = new_connection(addr, *realhost, port,
2602 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
2603 if ((err = sk_socket_error(ssh->s)) != NULL) {
2605 notify_remote_exit(ssh->frontend);
2613 * Throttle or unthrottle the SSH connection.
2615 static void ssh1_throttle(Ssh ssh, int adjust)
2617 int old_count = ssh->v1_throttle_count;
2618 ssh->v1_throttle_count += adjust;
2619 assert(ssh->v1_throttle_count >= 0);
2620 if (ssh->v1_throttle_count && !old_count) {
2621 ssh_set_frozen(ssh, 1);
2622 } else if (!ssh->v1_throttle_count && old_count) {
2623 ssh_set_frozen(ssh, 0);
2628 * Throttle or unthrottle _all_ local data streams (for when sends
2629 * on the SSH connection itself back up).
2631 static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
2634 struct ssh_channel *c;
2636 if (enable == ssh->throttled_all)
2638 ssh->throttled_all = enable;
2639 ssh->overall_bufsize = bufsize;
2642 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2644 case CHAN_MAINSESSION:
2646 * This is treated separately, outside the switch.
2650 x11_override_throttle(c->u.x11.s, enable);
2653 /* Agent channels require no buffer management. */
2656 pfd_override_throttle(c->u.pfd.s, enable);
2663 * Username and password input, abstracted off into routines
2664 * reusable in several places - even between SSH-1 and SSH-2.
2667 /* Set up a username or password input loop on a given buffer. */
2668 static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
2670 ssh->userpass_input_buffer = buffer;
2671 ssh->userpass_input_buflen = buflen;
2672 ssh->userpass_input_bufpos = 0;
2673 ssh->userpass_input_echo = echo;
2677 * Process some terminal data in the course of username/password
2678 * input. Returns >0 for success (line of input returned in
2679 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2680 * for inconclusive (keep waiting for more input please).
2682 static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
2687 switch (c = *in++) {
2690 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2691 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
2696 if (ssh->userpass_input_bufpos > 0) {
2697 if (ssh->userpass_input_echo)
2698 c_write_str(ssh, "\b \b");
2699 ssh->userpass_input_bufpos--;
2704 while (ssh->userpass_input_bufpos > 0) {
2705 if (ssh->userpass_input_echo)
2706 c_write_str(ssh, "\b \b");
2707 ssh->userpass_input_bufpos--;
2716 * This simplistic check for printability is disabled
2717 * when we're doing password input, because some people
2718 * have control characters in their passwords.o
2720 if ((!ssh->userpass_input_echo ||
2721 (c >= ' ' && c <= '~') ||
2722 ((unsigned char) c >= 160))
2723 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2724 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2725 if (ssh->userpass_input_echo)
2726 c_write(ssh, &c, 1);
2734 static void ssh_agent_callback(void *sshv, void *reply, int replylen)
2736 Ssh ssh = (Ssh) sshv;
2738 ssh->agent_response = reply;
2739 ssh->agent_response_len = replylen;
2741 if (ssh->version == 1)
2742 do_ssh1_login(ssh, NULL, -1, NULL);
2744 do_ssh2_authconn(ssh, NULL, -1, NULL);
2747 static void ssh_dialog_callback(void *sshv, int ret)
2749 Ssh ssh = (Ssh) sshv;
2751 ssh->user_response = ret;
2753 if (ssh->version == 1)
2754 do_ssh1_login(ssh, NULL, -1, NULL);
2756 do_ssh2_transport(ssh, NULL, -1, NULL);
2759 * This may have unfrozen the SSH connection, so do a
2762 ssh_process_queued_incoming_data(ssh);
2765 static void ssh_agentf_callback(void *cv, void *reply, int replylen)
2767 struct ssh_channel *c = (struct ssh_channel *)cv;
2769 void *sentreply = reply;
2772 /* Fake SSH_AGENT_FAILURE. */
2773 sentreply = "\0\0\0\1\5";
2776 if (ssh->version == 2) {
2777 ssh2_add_channel_data(c, sentreply, replylen);
2780 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2781 PKT_INT, c->remoteid,
2784 PKT_DATA, sentreply, replylen,
2793 * Handle the key exchange and user authentication phases.
2795 static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
2796 struct Packet *pktin)
2799 unsigned char cookie[8], *ptr;
2800 struct RSAKey servkey, hostkey;
2801 struct MD5Context md5c;
2802 struct do_ssh1_login_state {
2804 unsigned char *rsabuf, *keystr1, *keystr2;
2805 unsigned long supported_ciphers_mask, supported_auths_mask;
2806 int tried_publickey, tried_agent;
2807 int tis_auth_refused, ccard_auth_refused;
2808 unsigned char session_id[16];
2811 void *publickey_blob;
2812 int publickey_bloblen;
2818 unsigned char request[5], *response, *p;
2828 crState(do_ssh1_login_state);
2830 crBegin(ssh->do_ssh1_login_crstate);
2835 if (pktin->type != SSH1_SMSG_PUBLIC_KEY) {
2836 bombout(("Public key packet not received"));
2840 logevent("Received public keys");
2842 ptr = ssh_pkt_getdata(pktin, 8);
2844 bombout(("SSH-1 public key packet stopped before random cookie"));
2847 memcpy(cookie, ptr, 8);
2849 if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
2850 !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
2851 bombout(("Failed to read SSH-1 public keys from public key packet"));
2856 * Log the host key fingerprint.
2860 logevent("Host key fingerprint is:");
2861 strcpy(logmsg, " ");
2862 hostkey.comment = NULL;
2863 rsa_fingerprint(logmsg + strlen(logmsg),
2864 sizeof(logmsg) - strlen(logmsg), &hostkey);
2868 ssh->v1_remote_protoflags = ssh_pkt_getuint32(pktin);
2869 s->supported_ciphers_mask = ssh_pkt_getuint32(pktin);
2870 s->supported_auths_mask = ssh_pkt_getuint32(pktin);
2872 ssh->v1_local_protoflags =
2873 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2874 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
2877 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2878 MD5Update(&md5c, s->keystr1, servkey.bytes);
2879 MD5Update(&md5c, cookie, 8);
2880 MD5Final(s->session_id, &md5c);
2882 for (i = 0; i < 32; i++)
2883 ssh->session_key[i] = random_byte();
2886 * Verify that the `bits' and `bytes' parameters match.
2888 if (hostkey.bits > hostkey.bytes * 8 ||
2889 servkey.bits > servkey.bytes * 8) {
2890 bombout(("SSH-1 public keys were badly formatted"));
2894 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
2896 s->rsabuf = snewn(s->len, unsigned char);
2898 fatalbox("Out of memory");
2901 * Verify the host key.
2905 * First format the key into a string.
2907 int len = rsastr_len(&hostkey);
2908 char fingerprint[100];
2909 char *keystr = snewn(len, char);
2911 fatalbox("Out of memory");
2912 rsastr_fmt(keystr, &hostkey);
2913 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
2915 ssh_set_frozen(ssh, 1);
2916 s->dlgret = verify_ssh_host_key(ssh->frontend,
2917 ssh->savedhost, ssh->savedport,
2918 "rsa", keystr, fingerprint,
2919 ssh_dialog_callback, ssh);
2921 if (s->dlgret < 0) {
2925 bombout(("Unexpected data from server while waiting"
2926 " for user host key response"));
2929 } while (pktin || inlen > 0);
2930 s->dlgret = ssh->user_response;
2932 ssh_set_frozen(ssh, 0);
2934 if (s->dlgret == 0) {
2935 ssh->close_expected = TRUE;
2936 ssh_closing((Plug)ssh, NULL, 0, 0);
2941 for (i = 0; i < 32; i++) {
2942 s->rsabuf[i] = ssh->session_key[i];
2944 s->rsabuf[i] ^= s->session_id[i];
2947 if (hostkey.bytes > servkey.bytes) {
2948 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2950 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
2952 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2954 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2957 bombout(("SSH-1 public key encryptions failed due to bad formatting"));
2961 logevent("Encrypted session key");
2964 int cipher_chosen = 0, warn = 0;
2965 char *cipher_string = NULL;
2967 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
2968 int next_cipher = ssh->cfg.ssh_cipherlist[i];
2969 if (next_cipher == CIPHER_WARN) {
2970 /* If/when we choose a cipher, warn about it */
2972 } else if (next_cipher == CIPHER_AES) {
2973 /* XXX Probably don't need to mention this. */
2974 logevent("AES not supported in SSH-1, skipping");
2976 switch (next_cipher) {
2977 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
2978 cipher_string = "3DES"; break;
2979 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
2980 cipher_string = "Blowfish"; break;
2981 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
2982 cipher_string = "single-DES"; break;
2984 if (s->supported_ciphers_mask & (1 << s->cipher_type))
2988 if (!cipher_chosen) {
2989 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
2990 bombout(("Server violates SSH-1 protocol by not "
2991 "supporting 3DES encryption"));
2993 /* shouldn't happen */
2994 bombout(("No supported ciphers found"));
2998 /* Warn about chosen cipher if necessary. */
3000 ssh_set_frozen(ssh, 1);
3001 s->dlgret = askalg(ssh->frontend, "cipher", cipher_string,
3002 ssh_dialog_callback, ssh);
3003 if (s->dlgret < 0) {
3007 bombout(("Unexpected data from server while waiting"
3008 " for user response"));
3011 } while (pktin || inlen > 0);
3012 s->dlgret = ssh->user_response;
3014 ssh_set_frozen(ssh, 0);
3015 if (s->dlgret == 0) {
3016 ssh->close_expected = TRUE;
3017 ssh_closing((Plug)ssh, NULL, 0, 0);
3023 switch (s->cipher_type) {
3024 case SSH_CIPHER_3DES:
3025 logevent("Using 3DES encryption");
3027 case SSH_CIPHER_DES:
3028 logevent("Using single-DES encryption");
3030 case SSH_CIPHER_BLOWFISH:
3031 logevent("Using Blowfish encryption");
3035 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
3036 PKT_CHAR, s->cipher_type,
3037 PKT_DATA, cookie, 8,
3038 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
3039 PKT_DATA, s->rsabuf, s->len,
3040 PKT_INT, ssh->v1_local_protoflags, PKT_END);
3042 logevent("Trying to enable encryption...");
3046 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
3047 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
3049 ssh->v1_cipher_ctx = ssh->cipher->make_context();
3050 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
3051 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
3053 ssh->crcda_ctx = crcda_make_context();
3054 logevent("Installing CRC compensation attack detector");
3056 if (servkey.modulus) {
3057 sfree(servkey.modulus);
3058 servkey.modulus = NULL;
3060 if (servkey.exponent) {
3061 sfree(servkey.exponent);
3062 servkey.exponent = NULL;
3064 if (hostkey.modulus) {
3065 sfree(hostkey.modulus);
3066 hostkey.modulus = NULL;
3068 if (hostkey.exponent) {
3069 sfree(hostkey.exponent);
3070 hostkey.exponent = NULL;
3074 if (pktin->type != SSH1_SMSG_SUCCESS) {
3075 bombout(("Encryption not successfully enabled"));
3079 logevent("Successfully started encryption");
3083 if (!*ssh->cfg.username) {
3084 if (ssh_get_line && !ssh_getline_pw_only) {
3085 if (!ssh_get_line("login as: ",
3086 s->username, sizeof(s->username), FALSE)) {
3088 * get_line failed to get a username.
3091 logevent("No username provided. Abandoning session.");
3092 ssh->close_expected = TRUE;
3093 ssh_closing((Plug)ssh, NULL, 0, 0);
3097 int ret; /* need not be kept over crReturn */
3098 c_write_str(ssh, "login as: ");
3101 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
3103 crWaitUntil(!pktin);
3104 ret = process_userpass_input(ssh, in, inlen);
3108 c_write_str(ssh, "\r\n");
3111 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
3112 s->username[sizeof(s->username)-1] = '\0';
3115 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
3117 char userlog[22 + sizeof(s->username)];
3118 sprintf(userlog, "Sent username \"%s\"", s->username);
3120 if (flags & FLAG_INTERACTIVE &&
3121 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3122 strcat(userlog, "\r\n");
3123 c_write_str(ssh, userlog);
3130 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
3131 /* We must not attempt PK auth. Pretend we've already tried it. */
3132 s->tried_publickey = s->tried_agent = 1;
3134 s->tried_publickey = s->tried_agent = 0;
3136 s->tis_auth_refused = s->ccard_auth_refused = 0;
3137 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3138 if (!filename_is_null(ssh->cfg.keyfile)) {
3139 if (!rsakey_pubblob(&ssh->cfg.keyfile,
3140 &s->publickey_blob, &s->publickey_bloblen, NULL))
3141 s->publickey_blob = NULL;
3143 s->publickey_blob = NULL;
3145 while (pktin->type == SSH1_SMSG_FAILURE) {
3146 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
3148 if (agent_exists() && !s->tried_agent) {
3150 * Attempt RSA authentication using Pageant.
3156 logevent("Pageant is running. Requesting keys.");
3158 /* Request the keys held by the agent. */
3159 PUT_32BIT(s->request, 1);
3160 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
3161 if (!agent_query(s->request, 5, &r, &s->responselen,
3162 ssh_agent_callback, ssh)) {
3166 bombout(("Unexpected data from server while waiting"
3167 " for agent response"));
3170 } while (pktin || inlen > 0);
3171 r = ssh->agent_response;
3172 s->responselen = ssh->agent_response_len;
3174 s->response = (unsigned char *) r;
3175 if (s->response && s->responselen >= 5 &&
3176 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
3177 s->p = s->response + 5;
3178 s->nkeys = GET_32BIT(s->p);
3180 logeventf(ssh, "Pageant has %d SSH-1 keys", s->nkeys);
3181 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
3182 logeventf(ssh, "Trying Pageant key #%d", s->keyi);
3183 if (s->publickey_blob &&
3184 !memcmp(s->p, s->publickey_blob,
3185 s->publickey_bloblen)) {
3186 logevent("This key matches configured key file");
3187 s->tried_publickey = 1;
3192 do { /* do while (0) to make breaking easy */
3193 n = ssh1_read_bignum
3194 (s->p, s->responselen-(s->p-s->response),
3199 n = ssh1_read_bignum
3200 (s->p, s->responselen-(s->p-s->response),
3205 if (s->responselen - (s->p-s->response) < 4)
3207 s->commentlen = GET_32BIT(s->p);
3209 if (s->responselen - (s->p-s->response) <
3212 s->commentp = (char *)s->p;
3213 s->p += s->commentlen;
3217 logevent("Pageant key list packet was truncated");
3221 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3222 PKT_BIGNUM, s->key.modulus, PKT_END);
3224 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
3225 logevent("Key refused");
3228 logevent("Received RSA challenge");
3229 if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
3230 bombout(("Server's RSA challenge was badly formatted"));
3235 char *agentreq, *q, *ret;
3238 len = 1 + 4; /* message type, bit count */
3239 len += ssh1_bignum_length(s->key.exponent);
3240 len += ssh1_bignum_length(s->key.modulus);
3241 len += ssh1_bignum_length(s->challenge);
3242 len += 16; /* session id */
3243 len += 4; /* response format */
3244 agentreq = snewn(4 + len, char);
3245 PUT_32BIT(agentreq, len);
3247 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
3248 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
3250 q += ssh1_write_bignum(q, s->key.exponent);
3251 q += ssh1_write_bignum(q, s->key.modulus);
3252 q += ssh1_write_bignum(q, s->challenge);
3253 memcpy(q, s->session_id, 16);
3255 PUT_32BIT(q, 1); /* response format */
3256 if (!agent_query(agentreq, len + 4, &vret, &retlen,
3257 ssh_agent_callback, ssh)) {
3262 bombout(("Unexpected data from server"
3263 " while waiting for agent"
3267 } while (pktin || inlen > 0);
3268 vret = ssh->agent_response;
3269 retlen = ssh->agent_response_len;
3274 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
3275 logevent("Sending Pageant's response");
3276 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3277 PKT_DATA, ret + 5, 16,
3281 if (pktin->type == SSH1_SMSG_SUCCESS) {
3283 ("Pageant's response accepted");
3284 if (flags & FLAG_VERBOSE) {
3285 c_write_str(ssh, "Authenticated using"
3287 c_write(ssh, s->commentp,
3289 c_write_str(ssh, "\" from agent\r\n");
3294 ("Pageant's response not accepted");
3297 ("Pageant failed to answer challenge");
3301 logevent("No reply received from Pageant");
3304 freebn(s->key.exponent);
3305 freebn(s->key.modulus);
3306 freebn(s->challenge);
3315 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
3316 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
3318 if (ssh->cfg.try_tis_auth &&
3319 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
3320 !s->tis_auth_refused) {
3321 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
3322 logevent("Requested TIS authentication");
3323 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
3325 if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
3326 logevent("TIS authentication declined");
3327 if (flags & FLAG_INTERACTIVE)
3328 c_write_str(ssh, "TIS authentication refused.\r\n");
3329 s->tis_auth_refused = 1;
3335 ssh_pkt_getstring(pktin, &challenge, &challengelen);
3337 bombout(("TIS challenge packet was badly formed"));
3340 c_write_str(ssh, "Using TIS authentication.\r\n");
3341 logevent("Received TIS challenge");
3342 if (challengelen > sizeof(s->prompt) - 1)
3343 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
3344 memcpy(s->prompt, challenge, challengelen);
3345 /* Prompt heuristic comes from OpenSSH */
3346 strncpy(s->prompt + challengelen,
3347 memchr(s->prompt, '\n', challengelen) ?
3348 "": "\r\nResponse: ",
3349 (sizeof s->prompt) - challengelen);
3350 s->prompt[(sizeof s->prompt) - 1] = '\0';
3353 if (ssh->cfg.try_tis_auth &&
3354 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
3355 !s->ccard_auth_refused) {
3356 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
3357 logevent("Requested CryptoCard authentication");
3358 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
3360 if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
3361 logevent("CryptoCard authentication declined");
3362 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
3363 s->ccard_auth_refused = 1;
3369 ssh_pkt_getstring(pktin, &challenge, &challengelen);
3371 bombout(("CryptoCard challenge packet was badly formed"));
3374 c_write_str(ssh, "Using CryptoCard authentication.\r\n");
3375 logevent("Received CryptoCard challenge");
3376 if (challengelen > sizeof(s->prompt) - 1)
3377 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
3378 memcpy(s->prompt, challenge, challengelen);
3379 strncpy(s->prompt + challengelen,
3380 memchr(s->prompt, '\n', challengelen) ?
3381 "" : "\r\nResponse: ",
3382 sizeof(s->prompt) - challengelen);
3383 s->prompt[sizeof(s->prompt) - 1] = '\0';
3386 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3387 sprintf(s->prompt, "%.90s@%.90s's password: ",
3388 s->username, ssh->savedhost);
3390 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
3391 char *comment = NULL;
3393 if (flags & FLAG_VERBOSE)
3394 c_write_str(ssh, "Trying public key authentication.\r\n");
3395 logeventf(ssh, "Trying public key \"%s\"",
3396 filename_to_str(&ssh->cfg.keyfile));
3397 type = key_type(&ssh->cfg.keyfile);
3398 if (type != SSH_KEYTYPE_SSH1) {
3399 char *msg = dupprintf("Key is of wrong type (%s)",
3400 key_type_to_str(type));
3402 c_write_str(ssh, msg);
3403 c_write_str(ssh, "\r\n");
3405 s->tried_publickey = 1;
3408 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
3409 if (flags & FLAG_VERBOSE)
3410 c_write_str(ssh, "No passphrase required.\r\n");
3413 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
3418 * Show password prompt, having first obtained it via a TIS
3419 * or CryptoCard exchange if we're doing TIS or CryptoCard
3423 if (!ssh_get_line(s->prompt, s->password,
3424 sizeof(s->password), TRUE)) {
3426 * get_line failed to get a password (for example
3427 * because one was supplied on the command line
3428 * which has already failed to work). Terminate.
3430 send_packet(ssh, SSH1_MSG_DISCONNECT,
3431 PKT_STR, "No more passwords available to try",
3433 logevent("Unable to authenticate");
3434 connection_fatal(ssh->frontend, "Unable to authenticate");
3435 ssh->close_expected = TRUE;
3436 ssh_closing((Plug)ssh, NULL, 0, 0);
3440 /* Prompt may have come from server. We've munged it a bit, so
3441 * we know it to be zero-terminated at least once. */
3442 int ret; /* need not be saved over crReturn */
3443 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3446 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
3448 crWaitUntil(!pktin);
3449 ret = process_userpass_input(ssh, in, inlen);
3453 c_write_str(ssh, "\r\n");
3457 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
3459 * Try public key authentication with the specified
3462 s->tried_publickey = 1;
3465 const char *error = NULL;
3466 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3469 c_write_str(ssh, "Couldn't load private key from ");
3470 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
3471 c_write_str(ssh, " (");
3472 c_write_str(ssh, error);
3473 c_write_str(ssh, ").\r\n");
3474 continue; /* go and try password */
3477 c_write_str(ssh, "Wrong passphrase.\r\n");
3478 s->tried_publickey = 0;
3479 continue; /* try again */
3484 * Send a public key attempt.
3486 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3487 PKT_BIGNUM, s->key.modulus, PKT_END);
3490 if (pktin->type == SSH1_SMSG_FAILURE) {
3491 c_write_str(ssh, "Server refused our public key.\r\n");
3492 continue; /* go and try password */
3494 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
3495 bombout(("Bizarre response to offer of public key"));
3501 unsigned char buffer[32];
3502 Bignum challenge, response;
3504 if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
3505 bombout(("Server's RSA challenge was badly formatted"));
3508 response = rsadecrypt(challenge, &s->key);
3509 freebn(s->key.private_exponent);/* burn the evidence */
3511 for (i = 0; i < 32; i++) {
3512 buffer[i] = bignum_byte(response, 31 - i);
3516 MD5Update(&md5c, buffer, 32);
3517 MD5Update(&md5c, s->session_id, 16);
3518 MD5Final(buffer, &md5c);
3520 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3521 PKT_DATA, buffer, 16, PKT_END);
3528 if (pktin->type == SSH1_SMSG_FAILURE) {
3529 if (flags & FLAG_VERBOSE)
3530 c_write_str(ssh, "Failed to authenticate with"
3531 " our public key.\r\n");
3532 continue; /* go and try password */
3533 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3534 bombout(("Bizarre response to RSA authentication response"));
3538 break; /* we're through! */
3540 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3542 * Defence against traffic analysis: we send a
3543 * whole bunch of packets containing strings of
3544 * different lengths. One of these strings is the
3545 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3546 * The others are all random data in
3547 * SSH1_MSG_IGNORE packets. This way a passive
3548 * listener can't tell which is the password, and
3549 * hence can't deduce the password length.
3551 * Anybody with a password length greater than 16
3552 * bytes is going to have enough entropy in their
3553 * password that a listener won't find it _that_
3554 * much help to know how long it is. So what we'll
3557 * - if password length < 16, we send 15 packets
3558 * containing string lengths 1 through 15
3560 * - otherwise, we let N be the nearest multiple
3561 * of 8 below the password length, and send 8
3562 * packets containing string lengths N through
3563 * N+7. This won't obscure the order of
3564 * magnitude of the password length, but it will
3565 * introduce a bit of extra uncertainty.
3567 * A few servers (the old 1.2.18 through 1.2.22)
3568 * can't deal with SSH1_MSG_IGNORE. For these
3569 * servers, we need an alternative defence. We make
3570 * use of the fact that the password is interpreted
3571 * as a C string: so we can append a NUL, then some
3574 * One server (a Cisco one) can deal with neither
3575 * SSH1_MSG_IGNORE _nor_ a padded password string.
3576 * For this server we are left with no defences
3577 * against password length sniffing.
3579 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
3581 * The server can deal with SSH1_MSG_IGNORE, so
3582 * we can use the primary defence.
3584 int bottom, top, pwlen, i;
3587 pwlen = strlen(s->password);
3589 bottom = 0; /* zero length passwords are OK! :-) */
3592 bottom = pwlen & ~7;
3596 assert(pwlen >= bottom && pwlen <= top);
3598 randomstr = snewn(top + 1, char);
3600 for (i = bottom; i <= top; i++) {
3602 defer_packet(ssh, s->pwpkt_type,
3603 PKTT_PASSWORD, PKT_STR, s->password,
3604 PKTT_OTHER, PKT_END);
3606 for (j = 0; j < i; j++) {
3608 randomstr[j] = random_byte();
3609 } while (randomstr[j] == '\0');
3611 randomstr[i] = '\0';
3612 defer_packet(ssh, SSH1_MSG_IGNORE,
3613 PKT_STR, randomstr, PKT_END);
3616 logevent("Sending password with camouflage packets");
3617 ssh_pkt_defersend(ssh);
3620 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
3622 * The server can't deal with SSH1_MSG_IGNORE
3623 * but can deal with padded passwords, so we
3624 * can use the secondary defence.
3630 len = strlen(s->password);
3631 if (len < sizeof(string)) {
3633 strcpy(string, s->password);
3634 len++; /* cover the zero byte */
3635 while (len < sizeof(string)) {
3636 string[len++] = (char) random_byte();
3641 logevent("Sending length-padded password");
3642 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3643 PKT_INT, len, PKT_DATA, ss, len,
3644 PKTT_OTHER, PKT_END);
3647 * The server has _both_
3648 * BUG_CHOKES_ON_SSH1_IGNORE and
3649 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3650 * therefore nothing we can do.
3653 len = strlen(s->password);
3654 logevent("Sending unpadded password");
3655 send_packet(ssh, s->pwpkt_type,
3656 PKTT_PASSWORD, PKT_INT, len,
3657 PKT_DATA, s->password, len,
3658 PKTT_OTHER, PKT_END);
3661 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3662 PKT_STR, s->password, PKTT_OTHER, PKT_END);
3665 logevent("Sent password");
3666 memset(s->password, 0, strlen(s->password));
3668 if (pktin->type == SSH1_SMSG_FAILURE) {
3669 if (flags & FLAG_VERBOSE)
3670 c_write_str(ssh, "Access denied\r\n");
3671 logevent("Authentication refused");
3672 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3673 bombout(("Strange packet received, type %d", pktin->type));
3678 logevent("Authentication successful");
3683 void sshfwd_close(struct ssh_channel *c)
3687 if (ssh->state == SSH_STATE_CLOSED)
3690 if (c && !c->closes) {
3692 * If halfopen is true, we have sent
3693 * CHANNEL_OPEN for this channel, but it hasn't even been
3694 * acknowledged by the server. So we must set a close flag
3695 * on it now, and then when the server acks the channel
3696 * open, we can close it then.
3699 if (ssh->version == 1) {
3700 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
3703 struct Packet *pktout;
3704 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3705 ssh2_pkt_adduint32(pktout, c->remoteid);
3706 ssh2_pkt_send(ssh, pktout);
3709 c->closes = 1; /* sent MSG_CLOSE */
3710 if (c->type == CHAN_X11) {
3712 logevent("Forwarded X11 connection terminated");
3713 } else if (c->type == CHAN_SOCKDATA ||
3714 c->type == CHAN_SOCKDATA_DORMANT) {
3716 logevent("Forwarded port closed");
3721 int sshfwd_write(struct ssh_channel *c, char *buf, int len)
3725 if (ssh->state == SSH_STATE_CLOSED)
3728 if (ssh->version == 1) {
3729 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
3730 PKT_INT, c->remoteid,
3732 PKT_INT, len, PKT_DATA, buf, len,
3733 PKTT_OTHER, PKT_END);
3735 * In SSH-1 we can return 0 here - implying that forwarded
3736 * connections are never individually throttled - because
3737 * the only circumstance that can cause throttling will be
3738 * the whole SSH connection backing up, in which case
3739 * _everything_ will be throttled as a whole.
3743 ssh2_add_channel_data(c, buf, len);
3744 return ssh2_try_send(c);
3748 void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3752 if (ssh->state == SSH_STATE_CLOSED)
3755 if (ssh->version == 1) {
3756 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3757 c->v.v1.throttling = 0;
3758 ssh1_throttle(ssh, -1);
3761 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
3765 static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
3767 struct queued_handler *qh = ssh->qhead;
3771 assert(pktin->type == qh->msg1 || pktin->type == qh->msg2);
3774 assert(ssh->packet_dispatch[qh->msg1] == ssh_queueing_handler);
3775 ssh->packet_dispatch[qh->msg1] = NULL;
3778 assert(ssh->packet_dispatch[qh->msg2] == ssh_queueing_handler);
3779 ssh->packet_dispatch[qh->msg2] = NULL;
3783 ssh->qhead = qh->next;
3785 if (ssh->qhead->msg1 > 0) {
3786 assert(ssh->packet_dispatch[ssh->qhead->msg1] == NULL);
3787 ssh->packet_dispatch[ssh->qhead->msg1] = ssh_queueing_handler;
3789 if (ssh->qhead->msg2 > 0) {
3790 assert(ssh->packet_dispatch[ssh->qhead->msg2] == NULL);
3791 ssh->packet_dispatch[ssh->qhead->msg2] = ssh_queueing_handler;
3794 ssh->qhead = ssh->qtail = NULL;
3795 ssh->packet_dispatch[pktin->type] = NULL;
3798 qh->handler(ssh, pktin, qh->ctx);
3803 static void ssh_queue_handler(Ssh ssh, int msg1, int msg2,
3804 chandler_fn_t handler, void *ctx)
3806 struct queued_handler *qh;
3808 qh = snew(struct queued_handler);
3811 qh->handler = handler;
3815 if (ssh->qtail == NULL) {
3819 assert(ssh->packet_dispatch[qh->msg1] == NULL);
3820 ssh->packet_dispatch[qh->msg1] = ssh_queueing_handler;
3823 assert(ssh->packet_dispatch[qh->msg2] == NULL);
3824 ssh->packet_dispatch[qh->msg2] = ssh_queueing_handler;
3827 ssh->qtail->next = qh;
3832 static void ssh_rportfwd_succfail(Ssh ssh, struct Packet *pktin, void *ctx)
3834 struct ssh_rportfwd *rpf, *pf = (struct ssh_rportfwd *)ctx;
3836 if (pktin->type == (ssh->version == 1 ? SSH1_SMSG_SUCCESS :
3837 SSH2_MSG_REQUEST_SUCCESS)) {
3838 logeventf(ssh, "Remote port forwarding from %s enabled",
3841 logeventf(ssh, "Remote port forwarding from %s refused",
3844 rpf = del234(ssh->rportfwds, pf);
3850 static void ssh_setup_portfwd(Ssh ssh, const Config *cfg)
3852 const char *portfwd_strptr = cfg->portfwd;
3853 struct ssh_portfwd *epf;
3856 if (!ssh->portfwds) {
3857 ssh->portfwds = newtree234(ssh_portcmp);
3860 * Go through the existing port forwardings and tag them
3861 * with status==DESTROY. Any that we want to keep will be
3862 * re-enabled (status==KEEP) as we go through the
3863 * configuration and find out which bits are the same as
3866 struct ssh_portfwd *epf;
3868 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3869 epf->status = DESTROY;
3872 while (*portfwd_strptr) {
3873 char address_family, type;
3874 int sport,dport,sserv,dserv;
3875 char sports[256], dports[256], saddr[256], host[256];
3878 address_family = 'A';
3880 if (*portfwd_strptr == 'A' ||
3881 *portfwd_strptr == '4' ||
3882 *portfwd_strptr == '6')
3883 address_family = *portfwd_strptr++;
3884 if (*portfwd_strptr == 'L' ||
3885 *portfwd_strptr == 'R' ||
3886 *portfwd_strptr == 'D')
3887 type = *portfwd_strptr++;
3892 while (*portfwd_strptr && *portfwd_strptr != '\t') {
3893 if (*portfwd_strptr == ':') {
3895 * We've seen a colon in the middle of the
3896 * source port number. This means that
3897 * everything we've seen until now is the
3898 * source _address_, so we'll move it into
3899 * saddr and start sports from the beginning
3904 if (ssh->version == 1 && type == 'R') {
3905 logeventf(ssh, "SSH-1 cannot handle remote source address "
3906 "spec \"%s\"; ignoring", sports);
3908 strcpy(saddr, sports);
3911 if (n < lenof(sports)-1) sports[n++] = *portfwd_strptr++;
3915 if (*portfwd_strptr == '\t')
3918 while (*portfwd_strptr && *portfwd_strptr != ':') {
3919 if (n < lenof(host)-1) host[n++] = *portfwd_strptr++;
3922 if (*portfwd_strptr == ':')
3925 while (*portfwd_strptr) {
3926 if (n < lenof(dports)-1) dports[n++] = *portfwd_strptr++;
3930 dport = atoi(dports);
3934 dport = net_service_lookup(dports);
3936 logeventf(ssh, "Service lookup failed for destination"
3937 " port \"%s\"", dports);
3941 while (*portfwd_strptr) portfwd_strptr++;
3945 portfwd_strptr++; /* eat the NUL and move to next one */
3947 sport = atoi(sports);
3951 sport = net_service_lookup(sports);
3953 logeventf(ssh, "Service lookup failed for source"
3954 " port \"%s\"", sports);
3957 if (sport && dport) {
3958 /* Set up a description of the source port. */
3959 struct ssh_portfwd *pfrec, *epfrec;
3961 pfrec = snew(struct ssh_portfwd);
3963 pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
3964 pfrec->sserv = sserv ? dupstr(sports) : NULL;
3965 pfrec->sport = sport;
3966 pfrec->daddr = *host ? dupstr(host) : NULL;
3967 pfrec->dserv = dserv ? dupstr(dports) : NULL;
3968 pfrec->dport = dport;
3969 pfrec->local = NULL;
3970 pfrec->remote = NULL;
3971 pfrec->addressfamily = (address_family == '4' ? ADDRTYPE_IPV4 :
3972 address_family == '6' ? ADDRTYPE_IPV6 :
3975 epfrec = add234(ssh->portfwds, pfrec);
3976 if (epfrec != pfrec) {
3978 * We already have a port forwarding with precisely
3979 * these parameters. Hence, no need to do anything;
3980 * simply tag the existing one as KEEP.
3982 epfrec->status = KEEP;
3983 free_portfwd(pfrec);
3985 pfrec->status = CREATE;
3991 * Now go through and destroy any port forwardings which were
3994 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3995 if (epf->status == DESTROY) {
3998 message = dupprintf("%s port forwarding from %s%s%d",
3999 epf->type == 'L' ? "local" :
4000 epf->type == 'R' ? "remote" : "dynamic",
4001 epf->saddr ? epf->saddr : "",
4002 epf->saddr ? ":" : "",
4005 if (epf->type != 'D') {
4006 char *msg2 = dupprintf("%s to %s:%d", message,
4007 epf->daddr, epf->dport);
4012 logeventf(ssh, "Cancelling %s", message);
4016 struct ssh_rportfwd *rpf = epf->remote;
4017 struct Packet *pktout;
4020 * Cancel the port forwarding at the server
4023 if (ssh->version == 1) {
4025 * We cannot cancel listening ports on the
4026 * server side in SSH-1! There's no message
4027 * to support it. Instead, we simply remove
4028 * the rportfwd record from the local end
4029 * so that any connections the server tries
4030 * to make on it are rejected.
4033 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
4034 ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
4035 ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
4037 ssh2_pkt_addstring(pktout, epf->saddr);
4038 } else if (ssh->cfg.rport_acceptall) {
4039 /* XXX: ssh->cfg.rport_acceptall may not represent
4040 * what was used to open the original connection,
4041 * since it's reconfigurable. */
4042 ssh2_pkt_addstring(pktout, "0.0.0.0");
4044 ssh2_pkt_addstring(pktout, "127.0.0.1");
4046 ssh2_pkt_adduint32(pktout, epf->sport);
4047 ssh2_pkt_send(ssh, pktout);
4050 del234(ssh->rportfwds, rpf);
4052 } else if (epf->local) {
4053 pfd_terminate(epf->local);
4056 delpos234(ssh->portfwds, i);
4058 i--; /* so we don't skip one in the list */
4062 * And finally, set up any new port forwardings (status==CREATE).
4064 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
4065 if (epf->status == CREATE) {
4066 char *sportdesc, *dportdesc;
4067 sportdesc = dupprintf("%s%s%s%s%d%s",
4068 epf->saddr ? epf->saddr : "",
4069 epf->saddr ? ":" : "",
4070 epf->sserv ? epf->sserv : "",
4071 epf->sserv ? "(" : "",
4073 epf->sserv ? ")" : "");
4074 if (epf->type == 'D') {
4077 dportdesc = dupprintf("%s:%s%s%d%s",
4079 epf->dserv ? epf->dserv : "",
4080 epf->dserv ? "(" : "",
4082 epf->dserv ? ")" : "");
4085 if (epf->type == 'L') {
4086 const char *err = pfd_addforward(epf->daddr, epf->dport,
4087 epf->saddr, epf->sport,
4090 epf->addressfamily);
4092 logeventf(ssh, "Local %sport %s forwarding to %s%s%s",
4093 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
4094 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
4095 sportdesc, dportdesc,
4096 err ? " failed: " : "", err ? err : "");
4097 } else if (epf->type == 'D') {
4098 const char *err = pfd_addforward(NULL, -1,
4099 epf->saddr, epf->sport,
4102 epf->addressfamily);
4104 logeventf(ssh, "Local %sport %s SOCKS dynamic forwarding%s%s",
4105 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
4106 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
4108 err ? " failed: " : "", err ? err : "");
4110 struct ssh_rportfwd *pf;
4113 * Ensure the remote port forwardings tree exists.
4115 if (!ssh->rportfwds) {
4116 if (ssh->version == 1)
4117 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
4119 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
4122 pf = snew(struct ssh_rportfwd);
4123 strncpy(pf->dhost, epf->daddr, lenof(pf->dhost)-1);
4124 pf->dhost[lenof(pf->dhost)-1] = '\0';
4125 pf->dport = epf->dport;
4126 pf->sport = epf->sport;
4127 if (add234(ssh->rportfwds, pf) != pf) {
4128 logeventf(ssh, "Duplicate remote port forwarding to %s:%d",
4129 epf->daddr, epf->dport);
4132 logeventf(ssh, "Requesting remote port %s"
4133 " forward to %s", sportdesc, dportdesc);
4135 pf->sportdesc = sportdesc;
4140 if (ssh->version == 1) {
4141 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
4142 PKT_INT, epf->sport,
4143 PKT_STR, epf->daddr,
4144 PKT_INT, epf->dport,
4146 ssh_queue_handler(ssh, SSH1_SMSG_SUCCESS,
4148 ssh_rportfwd_succfail, pf);
4150 struct Packet *pktout;
4151 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
4152 ssh2_pkt_addstring(pktout, "tcpip-forward");
4153 ssh2_pkt_addbool(pktout, 1);/* want reply */
4155 ssh2_pkt_addstring(pktout, epf->saddr);
4156 } else if (cfg->rport_acceptall) {
4157 ssh2_pkt_addstring(pktout, "0.0.0.0");
4159 ssh2_pkt_addstring(pktout, "127.0.0.1");
4161 ssh2_pkt_adduint32(pktout, epf->sport);
4162 ssh2_pkt_send(ssh, pktout);
4164 ssh_queue_handler(ssh, SSH2_MSG_REQUEST_SUCCESS,
4165 SSH2_MSG_REQUEST_FAILURE,
4166 ssh_rportfwd_succfail, pf);
4175 static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
4178 int stringlen, bufsize;
4180 ssh_pkt_getstring(pktin, &string, &stringlen);
4181 if (string == NULL) {
4182 bombout(("Incoming terminal data packet was badly formed"));
4186 bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
4188 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
4189 ssh->v1_stdout_throttling = 1;
4190 ssh1_throttle(ssh, +1);
4194 static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
4196 /* Remote side is trying to open a channel to talk to our
4197 * X-Server. Give them back a local channel number. */
4198 struct ssh_channel *c;
4199 int remoteid = ssh_pkt_getuint32(pktin);
4201 logevent("Received X11 connect request");
4202 /* Refuse if X11 forwarding is disabled. */
4203 if (!ssh->X11_fwd_enabled) {
4204 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4205 PKT_INT, remoteid, PKT_END);
4206 logevent("Rejected X11 connect request");
4208 c = snew(struct ssh_channel);
4211 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
4212 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
4213 logevent("Opening X11 forward connection failed");
4215 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4216 PKT_INT, remoteid, PKT_END);
4219 ("Opening X11 forward connection succeeded");
4220 c->remoteid = remoteid;
4221 c->halfopen = FALSE;
4222 c->localid = alloc_channel_id(ssh);
4224 c->v.v1.throttling = 0;
4225 c->type = CHAN_X11; /* identify channel type */
4226 add234(ssh->channels, c);
4227 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4228 PKT_INT, c->remoteid, PKT_INT,
4229 c->localid, PKT_END);
4230 logevent("Opened X11 forward channel");
4235 static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
4237 /* Remote side is trying to open a channel to talk to our
4238 * agent. Give them back a local channel number. */
4239 struct ssh_channel *c;
4240 int remoteid = ssh_pkt_getuint32(pktin);
4242 /* Refuse if agent forwarding is disabled. */
4243 if (!ssh->agentfwd_enabled) {
4244 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4245 PKT_INT, remoteid, PKT_END);
4247 c = snew(struct ssh_channel);
4249 c->remoteid = remoteid;
4250 c->halfopen = FALSE;
4251 c->localid = alloc_channel_id(ssh);
4253 c->v.v1.throttling = 0;
4254 c->type = CHAN_AGENT; /* identify channel type */
4255 c->u.a.lensofar = 0;
4256 add234(ssh->channels, c);
4257 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4258 PKT_INT, c->remoteid, PKT_INT, c->localid,
4263 static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
4265 /* Remote side is trying to open a channel to talk to a
4266 * forwarded port. Give them back a local channel number. */
4267 struct ssh_channel *c;
4268 struct ssh_rportfwd pf, *pfp;
4273 c = snew(struct ssh_channel);
4276 remoteid = ssh_pkt_getuint32(pktin);
4277 ssh_pkt_getstring(pktin, &host, &hostsize);
4278 port = ssh_pkt_getuint32(pktin);
4280 if (hostsize >= lenof(pf.dhost))
4281 hostsize = lenof(pf.dhost)-1;
4282 memcpy(pf.dhost, host, hostsize);
4283 pf.dhost[hostsize] = '\0';
4285 pfp = find234(ssh->rportfwds, &pf, NULL);
4288 logeventf(ssh, "Rejected remote port open request for %s:%d",
4290 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4291 PKT_INT, remoteid, PKT_END);
4293 logeventf(ssh, "Received remote port open request for %s:%d",
4295 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
4296 c, &ssh->cfg, pfp->pfrec->addressfamily);
4298 logeventf(ssh, "Port open failed: %s", e);
4300 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4301 PKT_INT, remoteid, PKT_END);
4303 c->remoteid = remoteid;
4304 c->halfopen = FALSE;
4305 c->localid = alloc_channel_id(ssh);
4307 c->v.v1.throttling = 0;
4308 c->type = CHAN_SOCKDATA; /* identify channel type */
4309 add234(ssh->channels, c);
4310 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4311 PKT_INT, c->remoteid, PKT_INT,
4312 c->localid, PKT_END);
4313 logevent("Forwarded port opened successfully");
4318 static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
4320 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4321 unsigned int localid = ssh_pkt_getuint32(pktin);
4322 struct ssh_channel *c;
4324 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4325 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4326 c->remoteid = localid;
4327 c->halfopen = FALSE;
4328 c->type = CHAN_SOCKDATA;
4329 c->v.v1.throttling = 0;
4330 pfd_confirm(c->u.pfd.s);
4333 if (c && c->closes) {
4335 * We have a pending close on this channel,
4336 * which we decided on before the server acked
4337 * the channel open. So now we know the
4338 * remoteid, we can close it again.
4340 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
4341 PKT_INT, c->remoteid, PKT_END);
4345 static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
4347 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4348 struct ssh_channel *c;
4350 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4351 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4352 logevent("Forwarded connection refused by server");
4353 pfd_close(c->u.pfd.s);
4354 del234(ssh->channels, c);
4359 static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
4361 /* Remote side closes a channel. */
4362 unsigned i = ssh_pkt_getuint32(pktin);
4363 struct ssh_channel *c;
4364 c = find234(ssh->channels, &i, ssh_channelfind);
4365 if (c && !c->halfopen) {
4368 (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
4370 if ((c->closes == 0) && (c->type == CHAN_X11)) {
4371 logevent("Forwarded X11 connection terminated");
4372 assert(c->u.x11.s != NULL);
4373 x11_close(c->u.x11.s);
4376 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
4377 logevent("Forwarded port closed");
4378 assert(c->u.pfd.s != NULL);
4379 pfd_close(c->u.pfd.s);
4383 c->closes |= (closetype << 2); /* seen this message */
4384 if (!(c->closes & closetype)) {
4385 send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
4387 c->closes |= closetype; /* sent it too */
4390 if (c->closes == 15) {
4391 del234(ssh->channels, c);
4395 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4396 pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
4397 "_CONFIRMATION", c ? "half-open" : "nonexistent",
4402 static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
4404 /* Data sent down one of our channels. */
4405 int i = ssh_pkt_getuint32(pktin);
4408 struct ssh_channel *c;
4410 ssh_pkt_getstring(pktin, &p, &len);
4412 c = find234(ssh->channels, &i, ssh_channelfind);
4417 bufsize = x11_send(c->u.x11.s, p, len);
4420 bufsize = pfd_send(c->u.pfd.s, p, len);
4423 /* Data for an agent message. Buffer it. */
4425 if (c->u.a.lensofar < 4) {
4426 unsigned int l = min(4 - c->u.a.lensofar, len);
4427 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
4431 c->u.a.lensofar += l;
4433 if (c->u.a.lensofar == 4) {
4435 4 + GET_32BIT(c->u.a.msglen);
4436 c->u.a.message = snewn(c->u.a.totallen,
4438 memcpy(c->u.a.message, c->u.a.msglen, 4);
4440 if (c->u.a.lensofar >= 4 && len > 0) {
4442 min(c->u.a.totallen - c->u.a.lensofar,
4444 memcpy(c->u.a.message + c->u.a.lensofar, p,
4448 c->u.a.lensofar += l;
4450 if (c->u.a.lensofar == c->u.a.totallen) {
4453 if (agent_query(c->u.a.message,
4456 ssh_agentf_callback, c))
4457 ssh_agentf_callback(c, reply, replylen);
4458 sfree(c->u.a.message);
4459 c->u.a.lensofar = 0;
4462 bufsize = 0; /* agent channels never back up */
4465 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
4466 c->v.v1.throttling = 1;
4467 ssh1_throttle(ssh, +1);
4472 static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
4474 ssh->exitcode = ssh_pkt_getuint32(pktin);
4475 logeventf(ssh, "Server sent command exit status %d", ssh->exitcode);
4476 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4478 * In case `helpful' firewalls or proxies tack
4479 * extra human-readable text on the end of the
4480 * session which we might mistake for another
4481 * encrypted packet, we close the session once
4482 * we've sent EXIT_CONFIRMATION.
4484 ssh->close_expected = TRUE;
4485 ssh_closing((Plug)ssh, NULL, 0, 0);
4488 static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
4489 struct Packet *pktin)
4491 crBegin(ssh->do_ssh1_connection_crstate);
4493 ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
4494 ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
4495 ssh1_smsg_stdout_stderr_data;
4497 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
4498 ssh1_msg_channel_open_confirmation;
4499 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
4500 ssh1_msg_channel_open_failure;
4501 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
4502 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
4503 ssh1_msg_channel_close;
4504 ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
4505 ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
4507 if (ssh->cfg.agentfwd && agent_exists()) {
4508 logevent("Requesting agent forwarding");
4509 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
4513 if (pktin->type != SSH1_SMSG_SUCCESS
4514 && pktin->type != SSH1_SMSG_FAILURE) {
4515 bombout(("Protocol confusion"));
4517 } else if (pktin->type == SSH1_SMSG_FAILURE) {
4518 logevent("Agent forwarding refused");
4520 logevent("Agent forwarding enabled");
4521 ssh->agentfwd_enabled = TRUE;
4522 ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
4526 if (ssh->cfg.x11_forward) {
4527 char proto[20], data[64];
4528 logevent("Requesting X11 forwarding");
4529 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
4530 data, sizeof(data), ssh->cfg.x11_auth);
4531 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
4532 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
4533 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
4534 PKT_STR, proto, PKT_STR, data,
4535 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
4538 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
4539 PKT_STR, proto, PKT_STR, data, PKT_END);
4544 if (pktin->type != SSH1_SMSG_SUCCESS
4545 && pktin->type != SSH1_SMSG_FAILURE) {
4546 bombout(("Protocol confusion"));
4548 } else if (pktin->type == SSH1_SMSG_FAILURE) {
4549 logevent("X11 forwarding refused");
4551 logevent("X11 forwarding enabled");
4552 ssh->X11_fwd_enabled = TRUE;
4553 ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
4557 ssh_setup_portfwd(ssh, &ssh->cfg);
4558 ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] = ssh1_msg_port_open;
4560 if (!ssh->cfg.nopty) {
4561 /* Unpick the terminal-speed string. */
4562 /* XXX perhaps we should allow no speeds to be sent. */
4563 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
4564 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
4565 /* Send the pty request. */
4566 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
4567 PKT_STR, ssh->cfg.termtype,
4568 PKT_INT, ssh->term_height,
4569 PKT_INT, ssh->term_width,
4570 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
4571 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
4572 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
4573 PKT_CHAR, 0, PKT_END);
4574 ssh->state = SSH_STATE_INTERMED;
4578 if (pktin->type != SSH1_SMSG_SUCCESS
4579 && pktin->type != SSH1_SMSG_FAILURE) {
4580 bombout(("Protocol confusion"));
4582 } else if (pktin->type == SSH1_SMSG_FAILURE) {
4583 c_write_str(ssh, "Server refused to allocate pty\r\n");
4584 ssh->editing = ssh->echoing = 1;
4586 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4587 ssh->ospeed, ssh->ispeed);
4589 ssh->editing = ssh->echoing = 1;
4592 if (ssh->cfg.compression) {
4593 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
4597 if (pktin->type != SSH1_SMSG_SUCCESS
4598 && pktin->type != SSH1_SMSG_FAILURE) {
4599 bombout(("Protocol confusion"));
4601 } else if (pktin->type == SSH1_SMSG_FAILURE) {
4602 c_write_str(ssh, "Server refused to compress\r\n");
4604 logevent("Started compression");
4605 ssh->v1_compressing = TRUE;
4606 ssh->cs_comp_ctx = zlib_compress_init();
4607 logevent("Initialised zlib (RFC1950) compression");
4608 ssh->sc_comp_ctx = zlib_decompress_init();
4609 logevent("Initialised zlib (RFC1950) decompression");
4613 * Start the shell or command.
4615 * Special case: if the first-choice command is an SSH-2
4616 * subsystem (hence not usable here) and the second choice
4617 * exists, we fall straight back to that.
4620 char *cmd = ssh->cfg.remote_cmd_ptr;
4622 if (!cmd) cmd = ssh->cfg.remote_cmd;
4624 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
4625 cmd = ssh->cfg.remote_cmd_ptr2;
4626 ssh->fallback_cmd = TRUE;
4629 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
4631 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
4632 logevent("Started session");
4635 ssh->state = SSH_STATE_SESSION;
4636 if (ssh->size_needed)
4637 ssh_size(ssh, ssh->term_width, ssh->term_height);
4638 if (ssh->eof_needed)
4639 ssh_special(ssh, TS_EOF);
4642 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
4644 ssh->channels = newtree234(ssh_channelcmp);
4648 * By this point, most incoming packets are already being
4649 * handled by the dispatch table, and we need only pay
4650 * attention to the unusual ones.
4655 if (pktin->type == SSH1_SMSG_SUCCESS) {
4656 /* may be from EXEC_SHELL on some servers */
4657 } else if (pktin->type == SSH1_SMSG_FAILURE) {
4658 /* may be from EXEC_SHELL on some servers
4659 * if no pty is available or in other odd cases. Ignore */
4661 bombout(("Strange packet received: type %d", pktin->type));
4666 int len = min(inlen, 512);
4667 send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
4668 PKT_INT, len, PKT_DATA, in, len,
4669 PKTT_OTHER, PKT_END);
4680 * Handle the top-level SSH-2 protocol.
4682 static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
4687 ssh_pkt_getstring(pktin, &msg, &msglen);
4688 logeventf(ssh, "Remote debug message: %.*s", msglen, msg);
4691 static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
4693 /* log reason code in disconnect message */
4697 ssh_pkt_getstring(pktin, &msg, &msglen);
4698 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
4701 static void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
4703 /* Do nothing, because we're ignoring it! Duhh. */
4706 static void ssh1_protocol_setup(Ssh ssh)
4711 * Most messages are handled by the coroutines.
4713 for (i = 0; i < 256; i++)
4714 ssh->packet_dispatch[i] = NULL;
4717 * These special message types we install handlers for.
4719 ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
4720 ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
4721 ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
4724 static void ssh1_protocol(Ssh ssh, void *vin, int inlen,
4725 struct Packet *pktin)
4727 unsigned char *in=(unsigned char*)vin;
4728 if (ssh->state == SSH_STATE_CLOSED)
4731 if (pktin && ssh->packet_dispatch[pktin->type]) {
4732 ssh->packet_dispatch[pktin->type](ssh, pktin);
4736 if (!ssh->protocol_initial_phase_done) {
4737 if (do_ssh1_login(ssh, in, inlen, pktin))
4738 ssh->protocol_initial_phase_done = TRUE;
4743 do_ssh1_connection(ssh, in, inlen, pktin);
4747 * Utility routine for decoding comma-separated strings in KEXINIT.
4749 static int in_commasep_string(char *needle, char *haystack, int haylen)
4752 if (!needle || !haystack) /* protect against null pointers */
4754 needlen = strlen(needle);
4757 * Is it at the start of the string?
4759 if (haylen >= needlen && /* haystack is long enough */
4760 !memcmp(needle, haystack, needlen) && /* initial match */
4761 (haylen == needlen || haystack[needlen] == ',')
4762 /* either , or EOS follows */
4766 * If not, search for the next comma and resume after that.
4767 * If no comma found, terminate.
4769 while (haylen > 0 && *haystack != ',')
4770 haylen--, haystack++;
4773 haylen--, haystack++; /* skip over comma itself */
4778 * Similar routine for checking whether we have the first string in a list.
4780 static int first_in_commasep_string(char *needle, char *haystack, int haylen)
4783 if (!needle || !haystack) /* protect against null pointers */
4785 needlen = strlen(needle);
4787 * Is it at the start of the string?
4789 if (haylen >= needlen && /* haystack is long enough */
4790 !memcmp(needle, haystack, needlen) && /* initial match */
4791 (haylen == needlen || haystack[needlen] == ',')
4792 /* either , or EOS follows */
4800 * SSH-2 key creation method.
4802 static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
4803 unsigned char *sessid, char chr,
4804 unsigned char *keyspace)
4807 /* First 20 bytes. */
4809 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
4811 SHA_Bytes(&s, H, 20);
4812 SHA_Bytes(&s, &chr, 1);
4813 SHA_Bytes(&s, sessid, 20);
4814 SHA_Final(&s, keyspace);
4815 /* Next 20 bytes. */
4817 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
4819 SHA_Bytes(&s, H, 20);
4820 SHA_Bytes(&s, keyspace, 20);
4821 SHA_Final(&s, keyspace + 20);
4825 * Handle the SSH-2 transport layer.
4827 static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
4828 struct Packet *pktin)
4830 unsigned char *in = (unsigned char *)vin;
4831 struct do_ssh2_transport_state {
4832 int nbits, pbits, warn_kex, warn_cscipher, warn_sccipher;
4833 Bignum p, g, e, f, K;
4834 int kex_init_value, kex_reply_value;
4835 const struct ssh_mac **maclist;
4837 const struct ssh2_cipher *cscipher_tobe;
4838 const struct ssh2_cipher *sccipher_tobe;
4839 const struct ssh_mac *csmac_tobe;
4840 const struct ssh_mac *scmac_tobe;
4841 const struct ssh_compress *cscomp_tobe;
4842 const struct ssh_compress *sccomp_tobe;
4843 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4844 int hostkeylen, siglen;
4845 void *hkey; /* actual host key */
4846 unsigned char exchange_hash[20];
4847 int n_preferred_kex;
4848 const struct ssh_kex *preferred_kex[KEX_MAX];
4849 int n_preferred_ciphers;
4850 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4851 const struct ssh_compress *preferred_comp;
4852 int got_session_id, activated_authconn;
4853 struct Packet *pktout;
4858 crState(do_ssh2_transport_state);
4860 crBegin(ssh->do_ssh2_transport_crstate);
4862 s->cscipher_tobe = s->sccipher_tobe = NULL;
4863 s->csmac_tobe = s->scmac_tobe = NULL;
4864 s->cscomp_tobe = s->sccomp_tobe = NULL;
4866 s->got_session_id = s->activated_authconn = FALSE;
4869 * Be prepared to work around the buggy MAC problem.
4871 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4872 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
4874 s->maclist = macs, s->nmacs = lenof(macs);
4877 ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
4879 int i, j, commalist_started;
4882 * Set up the preferred key exchange. (NULL => warn below here)
4884 s->n_preferred_kex = 0;
4885 for (i = 0; i < KEX_MAX; i++) {
4886 switch (ssh->cfg.ssh_kexlist[i]) {
4888 s->preferred_kex[s->n_preferred_kex++] =
4889 &ssh_diffiehellman_gex;
4892 s->preferred_kex[s->n_preferred_kex++] =
4893 &ssh_diffiehellman_group14;
4896 s->preferred_kex[s->n_preferred_kex++] =
4897 &ssh_diffiehellman_group1;
4900 /* Flag for later. Don't bother if it's the last in
4902 if (i < KEX_MAX - 1) {
4903 s->preferred_kex[s->n_preferred_kex++] = NULL;
4910 * Set up the preferred ciphers. (NULL => warn below here)
4912 s->n_preferred_ciphers = 0;
4913 for (i = 0; i < CIPHER_MAX; i++) {
4914 switch (ssh->cfg.ssh_cipherlist[i]) {
4915 case CIPHER_BLOWFISH:
4916 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4919 if (ssh->cfg.ssh2_des_cbc) {
4920 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4924 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4927 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4930 /* Flag for later. Don't bother if it's the last in
4932 if (i < CIPHER_MAX - 1) {
4933 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4940 * Set up preferred compression.
4942 if (ssh->cfg.compression)
4943 s->preferred_comp = &ssh_zlib;
4945 s->preferred_comp = &ssh_comp_none;
4948 * Enable queueing of outgoing auth- or connection-layer
4949 * packets while we are in the middle of a key exchange.
4951 ssh->queueing = TRUE;
4954 * Flag that KEX is in progress.
4956 ssh->kex_in_progress = TRUE;
4959 * Construct and send our key exchange packet.
4961 s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
4962 for (i = 0; i < 16; i++)
4963 ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
4964 /* List key exchange algorithms. */
4965 ssh2_pkt_addstring_start(s->pktout);
4966 commalist_started = 0;
4967 for (i = 0; i < s->n_preferred_kex; i++) {
4968 const struct ssh_kex *k = s->preferred_kex[i];
4969 if (!k) continue; /* warning flag */
4970 if (commalist_started)
4971 ssh2_pkt_addstring_str(s->pktout, ",");
4972 ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
4973 commalist_started = 1;
4975 /* List server host key algorithms. */
4976 ssh2_pkt_addstring_start(s->pktout);
4977 for (i = 0; i < lenof(hostkey_algs); i++) {
4978 ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
4979 if (i < lenof(hostkey_algs) - 1)
4980 ssh2_pkt_addstring_str(s->pktout, ",");
4982 /* List client->server encryption algorithms. */
4983 ssh2_pkt_addstring_start(s->pktout);
4984 commalist_started = 0;
4985 for (i = 0; i < s->n_preferred_ciphers; i++) {
4986 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4987 if (!c) continue; /* warning flag */
4988 for (j = 0; j < c->nciphers; j++) {
4989 if (commalist_started)
4990 ssh2_pkt_addstring_str(s->pktout, ",");
4991 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
4992 commalist_started = 1;
4995 /* List server->client encryption algorithms. */
4996 ssh2_pkt_addstring_start(s->pktout);
4997 commalist_started = 0;
4998 for (i = 0; i < s->n_preferred_ciphers; i++) {
4999 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
5000 if (!c) continue; /* warning flag */
5001 for (j = 0; j < c->nciphers; j++) {
5002 if (commalist_started)
5003 ssh2_pkt_addstring_str(s->pktout, ",");
5004 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
5005 commalist_started = 1;
5008 /* List client->server MAC algorithms. */
5009 ssh2_pkt_addstring_start(s->pktout);
5010 for (i = 0; i < s->nmacs; i++) {
5011 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
5012 if (i < s->nmacs - 1)
5013 ssh2_pkt_addstring_str(s->pktout, ",");
5015 /* List server->client MAC algorithms. */
5016 ssh2_pkt_addstring_start(s->pktout);
5017 for (i = 0; i < s->nmacs; i++) {
5018 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
5019 if (i < s->nmacs - 1)
5020 ssh2_pkt_addstring_str(s->pktout, ",");
5022 /* List client->server compression algorithms. */
5023 ssh2_pkt_addstring_start(s->pktout);
5024 assert(lenof(compressions) > 1);
5025 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
5026 for (i = 0; i < lenof(compressions); i++) {
5027 const struct ssh_compress *c = compressions[i];
5028 if (c != s->preferred_comp) {
5029 ssh2_pkt_addstring_str(s->pktout, ",");
5030 ssh2_pkt_addstring_str(s->pktout, c->name);
5033 /* List server->client compression algorithms. */
5034 ssh2_pkt_addstring_start(s->pktout);
5035 assert(lenof(compressions) > 1);
5036 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
5037 for (i = 0; i < lenof(compressions); i++) {
5038 const struct ssh_compress *c = compressions[i];
5039 if (c != s->preferred_comp) {
5040 ssh2_pkt_addstring_str(s->pktout, ",");
5041 ssh2_pkt_addstring_str(s->pktout, c->name);
5044 /* List client->server languages. Empty list. */
5045 ssh2_pkt_addstring_start(s->pktout);
5046 /* List server->client languages. Empty list. */
5047 ssh2_pkt_addstring_start(s->pktout);
5048 /* First KEX packet does _not_ follow, because we're not that brave. */
5049 ssh2_pkt_addbool(s->pktout, FALSE);
5051 ssh2_pkt_adduint32(s->pktout, 0);
5054 ssh->exhash = ssh->exhashbase;
5055 sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
5057 ssh2_pkt_send_noqueue(ssh, s->pktout);
5061 if (pktin->length > 5)
5062 sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
5065 * Now examine the other side's KEXINIT to see what we're up
5069 char *str, *preferred;
5072 if (pktin->type != SSH2_MSG_KEXINIT) {
5073 bombout(("expected key exchange packet from server"));
5077 ssh->hostkey = NULL;
5078 s->cscipher_tobe = NULL;
5079 s->sccipher_tobe = NULL;
5080 s->csmac_tobe = NULL;
5081 s->scmac_tobe = NULL;
5082 s->cscomp_tobe = NULL;
5083 s->sccomp_tobe = NULL;
5084 s->warn_kex = s->warn_cscipher = s->warn_sccipher = FALSE;
5086 pktin->savedpos += 16; /* skip garbage cookie */
5087 ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
5090 for (i = 0; i < s->n_preferred_kex; i++) {
5091 const struct ssh_kex *k = s->preferred_kex[i];
5095 if (!preferred) preferred = k->name;
5096 if (in_commasep_string(k->name, str, len))
5103 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
5104 str ? str : "(null)"));
5108 * Note that the server's guess is considered wrong if it doesn't match
5109 * the first algorithm in our list, even if it's still the algorithm
5112 s->guessok = first_in_commasep_string(preferred, str, len);
5113 ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
5114 for (i = 0; i < lenof(hostkey_algs); i++) {
5115 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
5116 ssh->hostkey = hostkey_algs[i];
5120 s->guessok = s->guessok &&
5121 first_in_commasep_string(hostkey_algs[0]->name, str, len);
5122 ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
5123 for (i = 0; i < s->n_preferred_ciphers; i++) {
5124 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
5126 s->warn_cscipher = TRUE;
5128 for (j = 0; j < c->nciphers; j++) {
5129 if (in_commasep_string(c->list[j]->name, str, len)) {
5130 s->cscipher_tobe = c->list[j];
5135 if (s->cscipher_tobe)
5138 if (!s->cscipher_tobe) {
5139 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5140 str ? str : "(null)"));
5144 ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
5145 for (i = 0; i < s->n_preferred_ciphers; i++) {
5146 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
5148 s->warn_sccipher = TRUE;
5150 for (j = 0; j < c->nciphers; j++) {
5151 if (in_commasep_string(c->list[j]->name, str, len)) {
5152 s->sccipher_tobe = c->list[j];
5157 if (s->sccipher_tobe)
5160 if (!s->sccipher_tobe) {
5161 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5162 str ? str : "(null)"));
5166 ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
5167 for (i = 0; i < s->nmacs; i++) {
5168 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5169 s->csmac_tobe = s->maclist[i];
5173 ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
5174 for (i = 0; i < s->nmacs; i++) {
5175 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5176 s->scmac_tobe = s->maclist[i];
5180 ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
5181 for (i = 0; i < lenof(compressions) + 1; i++) {
5182 const struct ssh_compress *c =
5183 i == 0 ? s->preferred_comp : compressions[i - 1];
5184 if (in_commasep_string(c->name, str, len)) {
5189 ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
5190 for (i = 0; i < lenof(compressions) + 1; i++) {
5191 const struct ssh_compress *c =
5192 i == 0 ? s->preferred_comp : compressions[i - 1];
5193 if (in_commasep_string(c->name, str, len)) {
5198 ssh_pkt_getstring(pktin, &str, &len); /* client->server language */
5199 ssh_pkt_getstring(pktin, &str, &len); /* server->client language */
5200 s->ignorepkt = ssh2_pkt_getbool(pktin) && !s->guessok;
5203 ssh_set_frozen(ssh, 1);
5204 s->dlgret = askalg(ssh->frontend, "key-exchange algorithm",
5206 ssh_dialog_callback, ssh);
5207 if (s->dlgret < 0) {
5211 bombout(("Unexpected data from server while"
5212 " waiting for user response"));
5215 } while (pktin || inlen > 0);
5216 s->dlgret = ssh->user_response;
5218 ssh_set_frozen(ssh, 0);
5219 if (s->dlgret == 0) {
5220 ssh->close_expected = TRUE;
5221 ssh_closing((Plug)ssh, NULL, 0, 0);
5226 if (s->warn_cscipher) {
5227 ssh_set_frozen(ssh, 1);
5228 s->dlgret = askalg(ssh->frontend,
5229 "client-to-server cipher",
5230 s->cscipher_tobe->name,
5231 ssh_dialog_callback, ssh);
5232 if (s->dlgret < 0) {
5236 bombout(("Unexpected data from server while"
5237 " waiting for user response"));
5240 } while (pktin || inlen > 0);
5241 s->dlgret = ssh->user_response;
5243 ssh_set_frozen(ssh, 0);
5244 if (s->dlgret == 0) {
5245 ssh->close_expected = TRUE;
5246 ssh_closing((Plug)ssh, NULL, 0, 0);
5251 if (s->warn_sccipher) {
5252 ssh_set_frozen(ssh, 1);
5253 s->dlgret = askalg(ssh->frontend,
5254 "server-to-client cipher",
5255 s->sccipher_tobe->name,
5256 ssh_dialog_callback, ssh);
5257 if (s->dlgret < 0) {
5261 bombout(("Unexpected data from server while"
5262 " waiting for user response"));
5265 } while (pktin || inlen > 0);
5266 s->dlgret = ssh->user_response;
5268 ssh_set_frozen(ssh, 0);
5269 if (s->dlgret == 0) {
5270 ssh->close_expected = TRUE;
5271 ssh_closing((Plug)ssh, NULL, 0, 0);
5276 if (s->ignorepkt) /* first_kex_packet_follows */
5277 crWaitUntil(pktin); /* Ignore packet */
5281 * Work out the number of bits of key we will need from the key
5282 * exchange. We start with the maximum key length of either
5288 csbits = s->cscipher_tobe->keylen;
5289 scbits = s->sccipher_tobe->keylen;
5290 s->nbits = (csbits > scbits ? csbits : scbits);
5292 /* The keys only have 160-bit entropy, since they're based on
5293 * a SHA-1 hash. So cap the key size at 160 bits. */
5298 * If we're doing Diffie-Hellman group exchange, start by
5299 * requesting a group.
5301 if (!ssh->kex->pdata) {
5302 logevent("Doing Diffie-Hellman group exchange");
5303 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
5305 * Work out how big a DH group we will need to allow that
5308 s->pbits = 512 << ((s->nbits - 1) / 64);
5309 s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
5310 ssh2_pkt_adduint32(s->pktout, s->pbits);
5311 ssh2_pkt_send_noqueue(ssh, s->pktout);
5314 if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
5315 bombout(("expected key exchange group packet from server"));
5318 s->p = ssh2_pkt_getmp(pktin);
5319 s->g = ssh2_pkt_getmp(pktin);
5320 if (!s->p || !s->g) {
5321 bombout(("unable to read mp-ints from incoming group packet"));
5324 ssh->kex_ctx = dh_setup_gex(s->p, s->g);
5325 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
5326 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
5328 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
5329 ssh->kex_ctx = dh_setup_group(ssh->kex);
5330 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
5331 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
5332 logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
5333 ssh->kex->groupname);
5336 logevent("Doing Diffie-Hellman key exchange");
5338 * Now generate and send e for Diffie-Hellman.
5340 set_busy_status(ssh->frontend, BUSY_CPU); /* this can take a while */
5341 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
5342 s->pktout = ssh2_pkt_init(s->kex_init_value);
5343 ssh2_pkt_addmp(s->pktout, s->e);
5344 ssh2_pkt_send_noqueue(ssh, s->pktout);
5346 set_busy_status(ssh->frontend, BUSY_WAITING); /* wait for server */
5348 if (pktin->type != s->kex_reply_value) {
5349 bombout(("expected key exchange reply packet from server"));
5352 set_busy_status(ssh->frontend, BUSY_CPU); /* cogitate */
5353 ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
5354 s->f = ssh2_pkt_getmp(pktin);
5356 bombout(("unable to parse key exchange reply packet"));
5359 ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
5361 s->K = dh_find_K(ssh->kex_ctx, s->f);
5363 /* We assume everything from now on will be quick, and it might
5364 * involve user interaction. */
5365 set_busy_status(ssh->frontend, BUSY_NOT);
5367 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
5368 if (ssh->kex == &ssh_diffiehellman_gex) {
5369 sha_uint32(&ssh->exhash, s->pbits);
5370 sha_mpint(&ssh->exhash, s->p);
5371 sha_mpint(&ssh->exhash, s->g);
5373 sha_mpint(&ssh->exhash, s->e);
5374 sha_mpint(&ssh->exhash, s->f);
5375 sha_mpint(&ssh->exhash, s->K);
5376 SHA_Final(&ssh->exhash, s->exchange_hash);
5378 dh_cleanup(ssh->kex_ctx);
5379 ssh->kex_ctx = NULL;
5382 debug(("Exchange hash is:\n"));
5383 dmemdump(s->exchange_hash, 20);
5386 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
5388 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
5389 (char *)s->exchange_hash, 20)) {
5390 bombout(("Server's host key did not match the signature supplied"));
5395 * Authenticate remote host: verify host key. (We've already
5396 * checked the signature of the exchange hash.)
5398 s->keystr = ssh->hostkey->fmtkey(s->hkey);
5399 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
5400 ssh_set_frozen(ssh, 1);
5401 s->dlgret = verify_ssh_host_key(ssh->frontend,
5402 ssh->savedhost, ssh->savedport,
5403 ssh->hostkey->keytype, s->keystr,
5405 ssh_dialog_callback, ssh);
5406 if (s->dlgret < 0) {
5410 bombout(("Unexpected data from server while waiting"
5411 " for user host key response"));
5414 } while (pktin || inlen > 0);
5415 s->dlgret = ssh->user_response;
5417 ssh_set_frozen(ssh, 0);
5418 if (s->dlgret == 0) {
5419 ssh->close_expected = TRUE;
5420 ssh_closing((Plug)ssh, NULL, 0, 0);
5423 if (!s->got_session_id) { /* don't bother logging this in rekeys */
5424 logevent("Host key fingerprint is:");
5425 logevent(s->fingerprint);
5427 sfree(s->fingerprint);
5429 ssh->hostkey->freekey(s->hkey);
5432 * The exchange hash from the very first key exchange is also
5433 * the session id, used in session key construction and
5436 if (!s->got_session_id) {
5437 memcpy(ssh->v2_session_id, s->exchange_hash,
5438 sizeof(s->exchange_hash));
5439 s->got_session_id = TRUE;
5443 * Send SSH2_MSG_NEWKEYS.
5445 s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
5446 ssh2_pkt_send_noqueue(ssh, s->pktout);
5447 ssh->outgoing_data_size = 0; /* start counting from here */
5450 * We've sent client NEWKEYS, so create and initialise
5451 * client-to-server session keys.
5453 if (ssh->cs_cipher_ctx)
5454 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
5455 ssh->cscipher = s->cscipher_tobe;
5456 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
5458 if (ssh->cs_mac_ctx)
5459 ssh->csmac->free_context(ssh->cs_mac_ctx);
5460 ssh->csmac = s->csmac_tobe;
5461 ssh->cs_mac_ctx = ssh->csmac->make_context();
5463 if (ssh->cs_comp_ctx)
5464 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
5465 ssh->cscomp = s->cscomp_tobe;
5466 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
5469 * Set IVs on client-to-server keys. Here we use the exchange
5470 * hash from the _first_ key exchange.
5473 unsigned char keyspace[40];
5474 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
5475 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
5476 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
5477 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
5478 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
5479 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
5482 logeventf(ssh, "Initialised %.200s client->server encryption",
5483 ssh->cscipher->text_name);
5484 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
5485 ssh->csmac->text_name);
5486 if (ssh->cscomp->text_name)
5487 logeventf(ssh, "Initialised %s compression",
5488 ssh->cscomp->text_name);
5491 * Now our end of the key exchange is complete, we can send all
5492 * our queued higher-layer packets.
5494 ssh->queueing = FALSE;
5495 ssh2_pkt_queuesend(ssh);
5498 * Expect SSH2_MSG_NEWKEYS from server.
5501 if (pktin->type != SSH2_MSG_NEWKEYS) {
5502 bombout(("expected new-keys packet from server"));
5505 ssh->incoming_data_size = 0; /* start counting from here */
5508 * We've seen server NEWKEYS, so create and initialise
5509 * server-to-client session keys.
5511 if (ssh->sc_cipher_ctx)
5512 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
5513 ssh->sccipher = s->sccipher_tobe;
5514 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
5516 if (ssh->sc_mac_ctx)
5517 ssh->scmac->free_context(ssh->sc_mac_ctx);
5518 ssh->scmac = s->scmac_tobe;
5519 ssh->sc_mac_ctx = ssh->scmac->make_context();
5521 if (ssh->sc_comp_ctx)
5522 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
5523 ssh->sccomp = s->sccomp_tobe;
5524 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
5527 * Set IVs on server-to-client keys. Here we use the exchange
5528 * hash from the _first_ key exchange.
5531 unsigned char keyspace[40];
5532 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
5533 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
5534 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
5535 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
5536 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
5537 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
5539 logeventf(ssh, "Initialised %.200s server->client encryption",
5540 ssh->sccipher->text_name);
5541 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
5542 ssh->scmac->text_name);
5543 if (ssh->sccomp->text_name)
5544 logeventf(ssh, "Initialised %s decompression",
5545 ssh->sccomp->text_name);
5548 * Free key exchange data.
5552 if (ssh->kex == &ssh_diffiehellman_gex) {
5558 * Key exchange is over. Loop straight back round if we have a
5559 * deferred rekey reason.
5561 if (ssh->deferred_rekey_reason) {
5562 logevent(ssh->deferred_rekey_reason);
5564 ssh->deferred_rekey_reason = NULL;
5565 goto begin_key_exchange;
5569 * Otherwise, schedule a timer for our next rekey.
5571 ssh->kex_in_progress = FALSE;
5572 ssh->last_rekey = GETTICKCOUNT();
5573 if (ssh->cfg.ssh_rekey_time != 0)
5574 ssh->next_rekey = schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5578 * If this is the first key exchange phase, we must pass the
5579 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5580 * wants to see it but because it will need time to initialise
5581 * itself before it sees an actual packet. In subsequent key
5582 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5583 * it would only confuse the layer above.
5585 if (s->activated_authconn) {
5588 s->activated_authconn = TRUE;
5591 * Now we're encrypting. Begin returning 1 to the protocol main
5592 * function so that other things can run on top of the
5593 * transport. If we ever see a KEXINIT, we must go back to the
5596 * We _also_ go back to the start if we see pktin==NULL and
5597 * inlen==-1, because this is a special signal meaning
5598 * `initiate client-driven rekey', and `in' contains a message
5599 * giving the reason for the rekey.
5601 while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
5602 (!pktin && inlen == -1))) {
5607 logevent("Server initiated key re-exchange");
5610 * Special case: if the server bug is set that doesn't
5611 * allow rekeying, we give a different log message and
5612 * continue waiting. (If such a server _initiates_ a rekey,
5613 * we process it anyway!)
5615 if ((ssh->remote_bugs & BUG_SSH2_REKEY)) {
5616 logeventf(ssh, "Server bug prevents key re-exchange (%s)",
5618 /* Reset the counters, so that at least this message doesn't
5619 * hit the event log _too_ often. */
5620 ssh->outgoing_data_size = 0;
5621 ssh->incoming_data_size = 0;
5622 if (ssh->cfg.ssh_rekey_time != 0) {
5624 schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5627 goto wait_for_rekey; /* this is utterly horrid */
5629 logeventf(ssh, "Initiating key re-exchange (%s)", (char *)in);
5632 goto begin_key_exchange;
5638 * Add data to an SSH-2 channel output buffer.
5640 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
5643 bufchain_add(&c->v.v2.outbuffer, buf, len);
5647 * Attempt to send data on an SSH-2 channel.
5649 static int ssh2_try_send(struct ssh_channel *c)
5652 struct Packet *pktout;
5654 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
5657 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
5658 if ((unsigned)len > c->v.v2.remwindow)
5659 len = c->v.v2.remwindow;
5660 if ((unsigned)len > c->v.v2.remmaxpkt)
5661 len = c->v.v2.remmaxpkt;
5662 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
5663 ssh2_pkt_adduint32(pktout, c->remoteid);
5664 dont_log_data(ssh, pktout, PKTLOG_OMIT);
5665 ssh2_pkt_addstring_start(pktout);
5666 ssh2_pkt_addstring_data(pktout, data, len);
5667 end_log_omission(ssh, pktout);
5668 ssh2_pkt_send(ssh, pktout);
5669 bufchain_consume(&c->v.v2.outbuffer, len);
5670 c->v.v2.remwindow -= len;
5674 * After having sent as much data as we can, return the amount
5677 return bufchain_size(&c->v.v2.outbuffer);
5680 static void ssh2_try_send_and_unthrottle(struct ssh_channel *c)
5684 return; /* don't send on closing channels */
5685 bufsize = ssh2_try_send(c);
5688 case CHAN_MAINSESSION:
5689 /* stdin need not receive an unthrottle
5690 * notification since it will be polled */
5693 x11_unthrottle(c->u.x11.s);
5696 /* agent sockets are request/response and need no
5697 * buffer management */
5700 pfd_unthrottle(c->u.pfd.s);
5707 * Potentially enlarge the window on an SSH-2 channel.
5709 static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
5714 * Never send WINDOW_ADJUST for a channel that the remote side
5715 * already thinks it's closed; there's no point, since it won't
5716 * be sending any more data anyway.
5722 * Only send a WINDOW_ADJUST if there's significantly more window
5723 * available than the other end thinks there is. This saves us
5724 * sending a WINDOW_ADJUST for every character in a shell session.
5726 * "Significant" is arbitrarily defined as half the window size.
5728 if (newwin > c->v.v2.locwindow * 2) {
5729 struct Packet *pktout;
5731 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5732 ssh2_pkt_adduint32(pktout, c->remoteid);
5733 ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
5734 ssh2_pkt_send(ssh, pktout);
5735 c->v.v2.locwindow = newwin;
5739 static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
5741 unsigned i = ssh_pkt_getuint32(pktin);
5742 struct ssh_channel *c;
5743 c = find234(ssh->channels, &i, ssh_channelfind);
5744 if (c && !c->closes) {
5745 c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
5746 ssh2_try_send_and_unthrottle(c);
5750 static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
5754 unsigned i = ssh_pkt_getuint32(pktin);
5755 struct ssh_channel *c;
5756 c = find234(ssh->channels, &i, ssh_channelfind);
5758 return; /* nonexistent channel */
5759 if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5760 ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
5761 return; /* extended but not stderr */
5762 ssh_pkt_getstring(pktin, &data, &length);
5765 c->v.v2.locwindow -= length;
5767 case CHAN_MAINSESSION:
5769 from_backend(ssh->frontend, pktin->type ==
5770 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5774 bufsize = x11_send(c->u.x11.s, data, length);
5777 bufsize = pfd_send(c->u.pfd.s, data, length);
5780 while (length > 0) {
5781 if (c->u.a.lensofar < 4) {
5782 unsigned int l = min(4 - c->u.a.lensofar, length);
5783 memcpy(c->u.a.msglen + c->u.a.lensofar,
5787 c->u.a.lensofar += l;
5789 if (c->u.a.lensofar == 4) {
5791 4 + GET_32BIT(c->u.a.msglen);
5792 c->u.a.message = snewn(c->u.a.totallen,
5794 memcpy(c->u.a.message, c->u.a.msglen, 4);
5796 if (c->u.a.lensofar >= 4 && length > 0) {
5798 min(c->u.a.totallen - c->u.a.lensofar,
5800 memcpy(c->u.a.message + c->u.a.lensofar,
5804 c->u.a.lensofar += l;
5806 if (c->u.a.lensofar == c->u.a.totallen) {
5809 if (agent_query(c->u.a.message,
5812 ssh_agentf_callback, c))
5813 ssh_agentf_callback(c, reply, replylen);
5814 sfree(c->u.a.message);
5815 c->u.a.lensofar = 0;
5822 * If we are not buffering too much data,
5823 * enlarge the window again at the remote side.
5825 if (bufsize < OUR_V2_WINSIZE)
5826 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
5830 static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
5832 unsigned i = ssh_pkt_getuint32(pktin);
5833 struct ssh_channel *c;
5835 c = find234(ssh->channels, &i, ssh_channelfind);
5837 return; /* nonexistent channel */
5839 if (c->type == CHAN_X11) {
5841 * Remote EOF on an X11 channel means we should
5842 * wrap up and close the channel ourselves.
5844 x11_close(c->u.x11.s);
5846 } else if (c->type == CHAN_AGENT) {
5848 } else if (c->type == CHAN_SOCKDATA) {
5849 pfd_close(c->u.pfd.s);
5854 static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
5856 unsigned i = ssh_pkt_getuint32(pktin);
5857 struct ssh_channel *c;
5858 struct Packet *pktout;
5860 c = find234(ssh->channels, &i, ssh_channelfind);
5861 if (!c || c->halfopen) {
5862 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5863 c ? "half-open" : "nonexistent", i));
5866 /* Do pre-close processing on the channel. */
5868 case CHAN_MAINSESSION:
5869 ssh->mainchan = NULL;
5870 update_specials_menu(ssh->frontend);
5873 if (c->u.x11.s != NULL)
5874 x11_close(c->u.x11.s);
5881 if (c->u.pfd.s != NULL)
5882 pfd_close(c->u.pfd.s);
5886 if (c->closes == 0) {
5887 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5888 ssh2_pkt_adduint32(pktout, c->remoteid);
5889 ssh2_pkt_send(ssh, pktout);
5891 del234(ssh->channels, c);
5892 bufchain_clear(&c->v.v2.outbuffer);
5896 * See if that was the last channel left open.
5897 * (This is only our termination condition if we're
5898 * not running in -N mode.)
5900 if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
5901 logevent("All channels closed. Disconnecting");
5904 * We used to send SSH_MSG_DISCONNECT here,
5905 * because I'd believed that _every_ conforming
5906 * SSH-2 connection had to end with a disconnect
5907 * being sent by at least one side; apparently
5908 * I was wrong and it's perfectly OK to
5909 * unceremoniously slam the connection shut
5910 * when you're done, and indeed OpenSSH feels
5911 * this is more polite than sending a
5912 * DISCONNECT. So now we don't.
5914 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5915 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
5916 ssh2_pkt_addstring(s->pktout, "All open channels closed");
5917 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5918 ssh2_pkt_send_noqueue(ssh, s->pktout);
5920 ssh->close_expected = TRUE;
5921 ssh_closing((Plug)ssh, NULL, 0, 0);
5925 static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
5927 unsigned i = ssh_pkt_getuint32(pktin);
5928 struct ssh_channel *c;
5929 struct Packet *pktout;
5931 c = find234(ssh->channels, &i, ssh_channelfind);
5933 return; /* nonexistent channel */
5934 if (c->type != CHAN_SOCKDATA_DORMANT)
5935 return; /* dunno why they're confirming this */
5936 c->remoteid = ssh_pkt_getuint32(pktin);
5937 c->halfopen = FALSE;
5938 c->type = CHAN_SOCKDATA;
5939 c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
5940 c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
5942 pfd_confirm(c->u.pfd.s);
5945 * We have a pending close on this channel,
5946 * which we decided on before the server acked
5947 * the channel open. So now we know the
5948 * remoteid, we can close it again.
5950 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5951 ssh2_pkt_adduint32(pktout, c->remoteid);
5952 ssh2_pkt_send(ssh, pktout);
5956 static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
5958 static const char *const reasons[] = {
5959 "<unknown reason code>",
5960 "Administratively prohibited",
5962 "Unknown channel type",
5963 "Resource shortage",
5965 unsigned i = ssh_pkt_getuint32(pktin);
5966 unsigned reason_code;
5967 char *reason_string;
5969 struct ssh_channel *c;
5970 c = find234(ssh->channels, &i, ssh_channelfind);
5972 return; /* nonexistent channel */
5973 if (c->type != CHAN_SOCKDATA_DORMANT)
5974 return; /* dunno why they're failing this */
5976 reason_code = ssh_pkt_getuint32(pktin);
5977 if (reason_code >= lenof(reasons))
5978 reason_code = 0; /* ensure reasons[reason_code] in range */
5979 ssh_pkt_getstring(pktin, &reason_string, &reason_length);
5980 logeventf(ssh, "Forwarded connection refused by server: %s [%.*s]",
5981 reasons[reason_code], reason_length, reason_string);
5983 pfd_close(c->u.pfd.s);
5985 del234(ssh->channels, c);
5989 static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
5993 int typelen, want_reply;
5994 int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
5995 struct ssh_channel *c;
5996 struct Packet *pktout;
5998 localid = ssh_pkt_getuint32(pktin);
5999 ssh_pkt_getstring(pktin, &type, &typelen);
6000 want_reply = ssh2_pkt_getbool(pktin);
6003 * First, check that the channel exists. Otherwise,
6004 * we can instantly disconnect with a rude message.
6006 c = find234(ssh->channels, &localid, ssh_channelfind);
6009 sprintf(buf, "Received channel request for nonexistent"
6010 " channel %d", localid);
6012 pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6013 ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
6014 ssh2_pkt_addstring(pktout, buf);
6015 ssh2_pkt_addstring(pktout, "en"); /* language tag */
6016 ssh2_pkt_send_noqueue(ssh, pktout);
6017 connection_fatal(ssh->frontend, "%s", buf);
6018 ssh->close_expected = TRUE;
6019 ssh_closing((Plug)ssh, NULL, 0, 0);
6024 * Having got the channel number, we now look at
6025 * the request type string to see if it's something
6028 if (c == ssh->mainchan) {
6030 * We recognise "exit-status" and "exit-signal" on
6031 * the primary channel.
6033 if (typelen == 11 &&
6034 !memcmp(type, "exit-status", 11)) {
6036 ssh->exitcode = ssh_pkt_getuint32(pktin);
6037 logeventf(ssh, "Server sent command exit status %d",
6039 reply = SSH2_MSG_CHANNEL_SUCCESS;
6041 } else if (typelen == 11 &&
6042 !memcmp(type, "exit-signal", 11)) {
6044 int is_plausible = TRUE, is_int = FALSE;
6045 char *fmt_sig = "", *fmt_msg = "";
6047 int msglen = 0, core = FALSE;
6048 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6049 * provide an `int' for the signal, despite its
6050 * having been a `string' in the drafts since at
6051 * least 2001. (Fixed in session.c 1.147.) Try to
6052 * infer which we can safely parse it as. */
6054 unsigned char *p = pktin->body +
6056 long len = pktin->length - pktin->savedpos;
6057 unsigned long num = GET_32BIT(p); /* what is it? */
6058 /* If it's 0, it hardly matters; assume string */
6062 int maybe_int = FALSE, maybe_str = FALSE;
6063 #define CHECK_HYPOTHESIS(offset, result) \
6066 if (q >= 0 && q+4 <= len) { \
6067 q = q + 4 + GET_32BIT(p+q); \
6068 if (q >= 0 && q+4 <= len && \
6069 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
6073 CHECK_HYPOTHESIS(4+1, maybe_int);
6074 CHECK_HYPOTHESIS(4+num+1, maybe_str);
6075 #undef CHECK_HYPOTHESIS
6076 if (maybe_int && !maybe_str)
6078 else if (!maybe_int && maybe_str)
6081 /* Crikey. Either or neither. Panic. */
6082 is_plausible = FALSE;
6087 /* Old non-standard OpenSSH. */
6088 int signum = ssh_pkt_getuint32(pktin);
6089 fmt_sig = dupprintf(" %d", signum);
6091 /* As per the drafts. */
6094 ssh_pkt_getstring(pktin, &sig, &siglen);
6095 /* Signal name isn't supposed to be blank, but
6096 * let's cope gracefully if it is. */
6098 fmt_sig = dupprintf(" \"%.*s\"",
6102 core = ssh2_pkt_getbool(pktin);
6103 ssh_pkt_getstring(pktin, &msg, &msglen);
6105 fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
6107 /* ignore lang tag */
6108 } /* else don't attempt to parse */
6109 logeventf(ssh, "Server exited on signal%s%s%s",
6110 fmt_sig, core ? " (core dumped)" : "",
6112 if (*fmt_sig) sfree(fmt_sig);
6113 if (*fmt_msg) sfree(fmt_msg);
6114 reply = SSH2_MSG_CHANNEL_SUCCESS;
6119 * This is a channel request we don't know
6120 * about, so we now either ignore the request
6121 * or respond with CHANNEL_FAILURE, depending
6124 reply = SSH2_MSG_CHANNEL_FAILURE;
6127 pktout = ssh2_pkt_init(reply);
6128 ssh2_pkt_adduint32(pktout, c->remoteid);
6129 ssh2_pkt_send(ssh, pktout);
6133 static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
6136 int typelen, want_reply;
6137 struct Packet *pktout;
6139 ssh_pkt_getstring(pktin, &type, &typelen);
6140 want_reply = ssh2_pkt_getbool(pktin);
6143 * We currently don't support any global requests
6144 * at all, so we either ignore the request or
6145 * respond with REQUEST_FAILURE, depending on
6149 pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
6150 ssh2_pkt_send(ssh, pktout);
6154 static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
6162 struct ssh_channel *c;
6163 unsigned remid, winsize, pktsize;
6164 struct Packet *pktout;
6166 ssh_pkt_getstring(pktin, &type, &typelen);
6167 c = snew(struct ssh_channel);
6170 remid = ssh_pkt_getuint32(pktin);
6171 winsize = ssh_pkt_getuint32(pktin);
6172 pktsize = ssh_pkt_getuint32(pktin);
6174 if (typelen == 3 && !memcmp(type, "x11", 3)) {
6177 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
6178 addrstr = snewn(peeraddrlen+1, char);
6179 memcpy(addrstr, peeraddr, peeraddrlen);
6180 addrstr[peeraddrlen] = '\0';
6181 peerport = ssh_pkt_getuint32(pktin);
6183 logeventf(ssh, "Received X11 connect request from %s:%d",
6186 if (!ssh->X11_fwd_enabled)
6187 error = "X11 forwarding is not enabled";
6188 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
6189 ssh->x11auth, addrstr, peerport,
6190 &ssh->cfg) != NULL) {
6191 error = "Unable to open an X11 connection";
6193 logevent("Opening X11 forward connection succeeded");
6198 } else if (typelen == 15 &&
6199 !memcmp(type, "forwarded-tcpip", 15)) {
6200 struct ssh_rportfwd pf, *realpf;
6203 ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
6204 pf.sport = ssh_pkt_getuint32(pktin);
6205 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
6206 peerport = ssh_pkt_getuint32(pktin);
6207 realpf = find234(ssh->rportfwds, &pf, NULL);
6208 logeventf(ssh, "Received remote port %d open request "
6209 "from %s:%d", pf.sport, peeraddr, peerport);
6210 if (realpf == NULL) {
6211 error = "Remote port is not recognised";
6213 const char *e = pfd_newconnect(&c->u.pfd.s,
6217 realpf->pfrec->addressfamily);
6218 logeventf(ssh, "Attempting to forward remote port to "
6219 "%s:%d", realpf->dhost, realpf->dport);
6221 logeventf(ssh, "Port open failed: %s", e);
6222 error = "Port open failed";
6224 logevent("Forwarded port opened successfully");
6225 c->type = CHAN_SOCKDATA;
6228 } else if (typelen == 22 &&
6229 !memcmp(type, "auth-agent@openssh.com", 3)) {
6230 if (!ssh->agentfwd_enabled)
6231 error = "Agent forwarding is not enabled";
6233 c->type = CHAN_AGENT; /* identify channel type */
6234 c->u.a.lensofar = 0;
6237 error = "Unsupported channel type requested";
6240 c->remoteid = remid;
6241 c->halfopen = FALSE;
6243 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
6244 ssh2_pkt_adduint32(pktout, c->remoteid);
6245 ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
6246 ssh2_pkt_addstring(pktout, error);
6247 ssh2_pkt_addstring(pktout, "en"); /* language tag */
6248 ssh2_pkt_send(ssh, pktout);
6249 logeventf(ssh, "Rejected channel open: %s", error);
6252 c->localid = alloc_channel_id(ssh);
6254 c->v.v2.locwindow = OUR_V2_WINSIZE;
6255 c->v.v2.remwindow = winsize;
6256 c->v.v2.remmaxpkt = pktsize;
6257 bufchain_init(&c->v.v2.outbuffer);
6258 add234(ssh->channels, c);
6259 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
6260 ssh2_pkt_adduint32(pktout, c->remoteid);
6261 ssh2_pkt_adduint32(pktout, c->localid);
6262 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
6263 ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
6264 ssh2_pkt_send(ssh, pktout);
6269 * Handle the SSH-2 userauth and connection layers.
6271 static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
6272 struct Packet *pktin)
6274 struct do_ssh2_authconn_state {
6276 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
6278 AUTH_KEYBOARD_INTERACTIVE
6282 AUTH_TYPE_PUBLICKEY,
6283 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
6284 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
6286 AUTH_TYPE_KEYBOARD_INTERACTIVE,
6287 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6289 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
6290 int tried_pubkey_config, tried_agent;
6291 int kbd_inter_running, kbd_inter_refused;
6293 int num_prompts, curr_prompt, echo;
6298 void *publickey_blob;
6299 int publickey_bloblen;
6300 unsigned char request[5], *response, *p;
6304 char *pkblob, *alg, *commentp;
6305 int pklen, alglen, commentlen;
6306 int siglen, retlen, len;
6307 char *q, *agentreq, *ret;
6309 int num_env, env_left, env_ok;
6310 struct Packet *pktout;
6312 crState(do_ssh2_authconn_state);
6314 crBegin(ssh->do_ssh2_authconn_crstate);
6317 * Request userauth protocol, and await a response to it.
6319 s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
6320 ssh2_pkt_addstring(s->pktout, "ssh-userauth");
6321 ssh2_pkt_send(ssh, s->pktout);
6322 crWaitUntilV(pktin);
6323 if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
6324 bombout(("Server refused user authentication protocol"));
6329 * We repeat this whole loop, including the username prompt,
6330 * until we manage a successful authentication. If the user
6331 * types the wrong _password_, they can be sent back to the
6332 * beginning to try another username, if this is configured on.
6333 * (If they specify a username in the config, they are never
6334 * asked, even if they do give a wrong password.)
6336 * I think this best serves the needs of
6338 * - the people who have no configuration, no keys, and just
6339 * want to try repeated (username,password) pairs until they
6340 * type both correctly
6342 * - people who have keys and configuration but occasionally
6343 * need to fall back to passwords
6345 * - people with a key held in Pageant, who might not have
6346 * logged in to a particular machine before; so they want to
6347 * type a username, and then _either_ their key will be
6348 * accepted, _or_ they will type a password. If they mistype
6349 * the username they will want to be able to get back and
6352 s->username[0] = '\0';
6353 s->got_username = FALSE;
6358 if (s->got_username && !ssh->cfg.change_username) {
6360 * We got a username last time round this loop, and
6361 * with change_username turned off we don't try to get
6364 } else if (!*ssh->cfg.username) {
6365 if (ssh_get_line && !ssh_getline_pw_only) {
6366 if (!ssh_get_line("login as: ",
6367 s->username, sizeof(s->username), FALSE)) {
6369 * get_line failed to get a username.
6372 logevent("No username provided. Abandoning session.");
6373 ssh->close_expected = TRUE;
6374 ssh_closing((Plug)ssh, NULL, 0, 0);
6378 int ret; /* need not be saved across crReturn */
6379 c_write_str(ssh, "login as: ");
6381 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
6383 crWaitUntilV(!pktin);
6384 ret = process_userpass_input(ssh, in, inlen);
6388 c_write_str(ssh, "\r\n");
6390 s->username[strcspn(s->username, "\n\r")] = '\0';
6393 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
6394 s->username[sizeof(s->username)-1] = '\0';
6395 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
6396 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
6397 c_write_str(ssh, stuff);
6401 s->got_username = TRUE;
6404 * Send an authentication request using method "none": (a)
6405 * just in case it succeeds, and (b) so that we know what
6406 * authentication methods we can usefully try next.
6408 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6410 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6411 ssh2_pkt_addstring(s->pktout, s->username);
6412 ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
6413 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6414 ssh2_pkt_send(ssh, s->pktout);
6415 s->type = AUTH_TYPE_NONE;
6417 s->we_are_in = FALSE;
6419 s->tried_pubkey_config = FALSE;
6420 s->tried_agent = FALSE;
6421 s->kbd_inter_running = FALSE;
6422 s->kbd_inter_refused = FALSE;
6423 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6424 if (!filename_is_null(ssh->cfg.keyfile)) {
6426 logeventf(ssh, "Reading private key file \"%.150s\"",
6427 filename_to_str(&ssh->cfg.keyfile));
6428 keytype = key_type(&ssh->cfg.keyfile);
6429 if (keytype == SSH_KEYTYPE_SSH2) {
6431 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
6432 &s->publickey_bloblen, NULL);
6435 logeventf(ssh, "Unable to use this key file (%s)",
6436 key_type_to_str(keytype));
6437 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6439 filename_to_str(&ssh->cfg.keyfile),
6440 key_type_to_str(keytype));
6441 c_write_str(ssh, msgbuf);
6443 s->publickey_blob = NULL;
6446 s->publickey_blob = NULL;
6450 * Wait for the result of the last authentication request.
6453 crWaitUntilV(pktin);
6454 while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
6458 * Don't show the banner if we're operating in
6459 * non-verbose non-interactive mode. (It's probably
6460 * a script, which means nobody will read the
6461 * banner _anyway_, and moreover the printing of
6462 * the banner will screw up processing on the
6463 * output of (say) plink.)
6465 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
6466 ssh_pkt_getstring(pktin, &banner, &size);
6468 c_write_untrusted(ssh, banner, size);
6470 crWaitUntilV(pktin);
6472 if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
6473 logevent("Access granted");
6474 s->we_are_in = TRUE;
6478 if (s->kbd_inter_running &&
6479 pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
6481 * This is either a further set-of-prompts packet
6482 * in keyboard-interactive authentication, or it's
6483 * the same one and we came back here with `gotit'
6484 * set. In the former case, we must reset the
6485 * curr_prompt variable.
6489 } else if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
6490 /* FIXME: perhaps we should support this? */
6491 bombout(("PASSWD_CHANGEREQ not yet supported"));
6493 } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
6494 bombout(("Strange packet received during authentication: type %d",
6502 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6503 * we can look at the string in it and know what we can
6504 * helpfully try next.
6506 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
6509 ssh_pkt_getstring(pktin, &methods, &methlen);
6510 s->kbd_inter_running = FALSE;
6511 if (!ssh2_pkt_getbool(pktin)) {
6513 * We have received an unequivocal Access
6514 * Denied. This can translate to a variety of
6517 * - if we'd just tried "none" authentication,
6518 * it's not worth printing anything at all
6520 * - if we'd just tried a public key _offer_,
6521 * the message should be "Server refused our
6522 * key" (or no message at all if the key
6523 * came from Pageant)
6525 * - if we'd just tried anything else, the
6526 * message really should be "Access denied".
6528 * Additionally, if we'd just tried password
6529 * authentication, we should break out of this
6530 * whole loop so as to go back to the username
6531 * prompt (iff we're configured to allow
6532 * username change attempts).
6534 if (s->type == AUTH_TYPE_NONE) {
6536 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
6537 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
6538 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
6539 c_write_str(ssh, "Server refused our key\r\n");
6540 logevent("Server refused public key");
6541 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
6542 /* server declined keyboard-interactive; ignore */
6544 c_write_str(ssh, "Access denied\r\n");
6545 logevent("Access denied");
6546 if (s->type == AUTH_TYPE_PASSWORD &&
6547 ssh->cfg.change_username) {
6548 /* XXX perhaps we should allow
6549 * keyboard-interactive to do this too? */
6550 s->we_are_in = FALSE;
6555 c_write_str(ssh, "Further authentication required\r\n");
6556 logevent("Further authentication required");
6560 in_commasep_string("publickey", methods, methlen);
6562 in_commasep_string("password", methods, methlen);
6563 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
6564 in_commasep_string("keyboard-interactive", methods, methlen);
6568 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6572 * Most password/passphrase prompts will be
6573 * non-echoing, so we set this to 0 by default.
6574 * Exception is that some keyboard-interactive prompts
6575 * can be echoing, in which case we'll set this to 1.
6579 if (!s->method && s->can_pubkey &&
6580 agent_exists() && !s->tried_agent) {
6582 * Attempt public-key authentication using Pageant.
6587 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6588 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
6590 s->tried_agent = TRUE;
6592 logevent("Pageant is running. Requesting keys.");
6594 /* Request the keys held by the agent. */
6595 PUT_32BIT(s->request, 1);
6596 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
6597 if (!agent_query(s->request, 5, &r, &s->responselen,
6598 ssh_agent_callback, ssh)) {
6602 bombout(("Unexpected data from server while"
6603 " waiting for agent response"));
6606 } while (pktin || inlen > 0);
6607 r = ssh->agent_response;
6608 s->responselen = ssh->agent_response_len;
6610 s->response = (unsigned char *) r;
6611 if (s->response && s->responselen >= 5 &&
6612 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
6613 s->p = s->response + 5;
6614 s->nkeys = GET_32BIT(s->p);
6616 logeventf(ssh, "Pageant has %d SSH-2 keys", s->nkeys);
6617 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
6620 logeventf(ssh, "Trying Pageant key #%d", s->keyi);
6621 s->pklen = GET_32BIT(s->p);
6623 if (s->publickey_blob &&
6624 s->pklen == s->publickey_bloblen &&
6625 !memcmp(s->p, s->publickey_blob,
6626 s->publickey_bloblen)) {
6627 logevent("This key matches configured key file");
6628 s->tried_pubkey_config = 1;
6630 s->pkblob = (char *)s->p;
6632 s->alglen = GET_32BIT(s->pkblob);
6633 s->alg = s->pkblob + 4;
6634 s->commentlen = GET_32BIT(s->p);
6636 s->commentp = (char *)s->p;
6637 s->p += s->commentlen;
6638 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6639 ssh2_pkt_addstring(s->pktout, s->username);
6640 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6641 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6642 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6643 ssh2_pkt_addstring_start(s->pktout);
6644 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6645 ssh2_pkt_addstring_start(s->pktout);
6646 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6647 ssh2_pkt_send(ssh, s->pktout);
6649 crWaitUntilV(pktin);
6650 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
6651 logevent("Key refused");
6655 if (flags & FLAG_VERBOSE) {
6656 c_write_str(ssh, "Authenticating with "
6658 c_write(ssh, s->commentp, s->commentlen);
6659 c_write_str(ssh, "\" from agent\r\n");
6663 * Server is willing to accept the key.
6664 * Construct a SIGN_REQUEST.
6666 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6667 ssh2_pkt_addstring(s->pktout, s->username);
6668 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6669 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6670 ssh2_pkt_addbool(s->pktout, TRUE);
6671 ssh2_pkt_addstring_start(s->pktout);
6672 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6673 ssh2_pkt_addstring_start(s->pktout);
6674 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6676 s->siglen = s->pktout->length - 5 + 4 + 20;
6677 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6679 s->len = 1; /* message type */
6680 s->len += 4 + s->pklen; /* key blob */
6681 s->len += 4 + s->siglen; /* data to sign */
6682 s->len += 4; /* flags */
6683 s->agentreq = snewn(4 + s->len, char);
6684 PUT_32BIT(s->agentreq, s->len);
6685 s->q = s->agentreq + 4;
6686 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
6687 PUT_32BIT(s->q, s->pklen);
6689 memcpy(s->q, s->pkblob, s->pklen);
6691 PUT_32BIT(s->q, s->siglen);
6693 /* Now the data to be signed... */
6694 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6695 PUT_32BIT(s->q, 20);
6698 memcpy(s->q, ssh->v2_session_id, 20);
6700 memcpy(s->q, s->pktout->data + 5,
6701 s->pktout->length - 5);
6702 s->q += s->pktout->length - 5;
6703 /* And finally the (zero) flags word. */
6705 if (!agent_query(s->agentreq, s->len + 4,
6707 ssh_agent_callback, ssh)) {
6711 bombout(("Unexpected data from server"
6712 " while waiting for agent"
6716 } while (pktin || inlen > 0);
6717 vret = ssh->agent_response;
6718 s->retlen = ssh->agent_response_len;
6723 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
6724 logevent("Sending Pageant's response");
6725 ssh2_add_sigblob(ssh, s->pktout,
6726 s->pkblob, s->pklen,
6728 GET_32BIT(s->ret + 5));
6729 ssh2_pkt_send(ssh, s->pktout);
6734 ("Pageant failed to answer challenge");
6745 if (!s->method && s->can_pubkey && s->publickey_blob
6746 && !s->tried_pubkey_config) {
6747 unsigned char *pub_blob;
6748 char *algorithm, *comment;
6751 s->tried_pubkey_config = TRUE;
6753 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6754 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
6757 * Try the public key supplied in the configuration.
6759 * First, offer the public blob to see if the server is
6760 * willing to accept it.
6763 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
6768 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6769 ssh2_pkt_addstring(s->pktout, s->username);
6770 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6771 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6772 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6773 ssh2_pkt_addstring(s->pktout, algorithm);
6774 ssh2_pkt_addstring_start(s->pktout);
6775 ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
6777 ssh2_pkt_send(ssh, s->pktout);
6778 logevent("Offered public key");
6780 crWaitUntilV(pktin);
6781 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
6783 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
6784 continue; /* key refused; give up on it */
6787 logevent("Offer of public key accepted");
6789 * Actually attempt a serious authentication using
6792 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
6793 sprintf(s->pwprompt,
6794 "Passphrase for key \"%.100s\": ",
6800 if (flags & FLAG_VERBOSE) {
6801 c_write_str(ssh, "Authenticating with public key \"");
6802 c_write_str(ssh, comment);
6803 c_write_str(ssh, "\"\r\n");
6805 s->method = AUTH_PUBLICKEY_FILE;
6809 if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
6810 !s->kbd_inter_running) {
6811 s->method = AUTH_KEYBOARD_INTERACTIVE;
6812 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
6814 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6815 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
6817 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6818 ssh2_pkt_addstring(s->pktout, s->username);
6819 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6820 ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
6821 ssh2_pkt_addstring(s->pktout, ""); /* lang */
6822 ssh2_pkt_addstring(s->pktout, "");
6823 ssh2_pkt_send(ssh, s->pktout);
6825 crWaitUntilV(pktin);
6826 if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
6827 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
6829 logevent("Keyboard-interactive authentication refused");
6830 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
6831 s->kbd_inter_refused = TRUE; /* don't try it again */
6835 c_write_str(ssh, "Using keyboard-interactive authentication.\r\n");
6836 s->kbd_inter_running = TRUE;
6840 if (s->kbd_inter_running) {
6841 s->method = AUTH_KEYBOARD_INTERACTIVE;
6842 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
6844 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6845 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
6847 if (s->curr_prompt == 0) {
6849 * We've got a fresh USERAUTH_INFO_REQUEST.
6850 * Display header data, and start going through
6853 char *name, *inst, *lang;
6854 int name_len, inst_len, lang_len;
6856 ssh_pkt_getstring(pktin, &name, &name_len);
6857 ssh_pkt_getstring(pktin, &inst, &inst_len);
6858 ssh_pkt_getstring(pktin, &lang, &lang_len);
6860 c_write_untrusted(ssh, name, name_len);
6861 c_write_str(ssh, "\r\n");
6864 c_write_untrusted(ssh, inst, inst_len);
6865 c_write_str(ssh, "\r\n");
6867 s->num_prompts = ssh_pkt_getuint32(pktin);
6871 * If there are prompts remaining in the packet,
6872 * display one and get a response.
6874 if (s->curr_prompt < s->num_prompts) {
6878 ssh_pkt_getstring(pktin, &prompt, &prompt_len);
6879 if (prompt_len > 0) {
6880 static const char trunc[] = "<prompt truncated>: ";
6881 static const int prlen = sizeof(s->pwprompt) -
6883 if (prompt_len > prlen) {
6884 memcpy(s->pwprompt, prompt, prlen);
6885 strcpy(s->pwprompt + prlen, trunc);
6887 memcpy(s->pwprompt, prompt, prompt_len);
6888 s->pwprompt[prompt_len] = '\0';
6892 "<server failed to send prompt>: ");
6894 s->echo = ssh2_pkt_getbool(pktin);
6900 if (!s->method && s->can_passwd) {
6901 s->method = AUTH_PASSWORD;
6902 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6903 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
6904 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
6911 if (!ssh_get_line(s->pwprompt, s->password,
6912 sizeof(s->password), TRUE)) {
6914 * get_line failed to get a password (for
6915 * example because one was supplied on the
6916 * command line which has already failed to
6919 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6920 ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
6921 ssh2_pkt_addstring(s->pktout, "No more passwords available"
6923 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
6924 ssh2_pkt_send_noqueue(ssh, s->pktout);
6925 logevent("Unable to authenticate");
6926 connection_fatal(ssh->frontend,
6927 "Unable to authenticate");
6928 ssh->close_expected = TRUE;
6929 ssh_closing((Plug)ssh, NULL, 0, 0);
6933 int ret; /* need not be saved across crReturn */
6934 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
6937 setup_userpass_input(ssh, s->password,
6938 sizeof(s->password), s->echo);
6940 crWaitUntilV(!pktin);
6941 ret = process_userpass_input(ssh, in, inlen);
6945 c_write_str(ssh, "\r\n");
6949 if (s->method == AUTH_PUBLICKEY_FILE) {
6951 * We have our passphrase. Now try the actual authentication.
6953 struct ssh2_userkey *key;
6954 const char *error = NULL;
6956 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
6958 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
6959 if (key == SSH2_WRONG_PASSPHRASE) {
6960 c_write_str(ssh, "Wrong passphrase\r\n");
6961 s->tried_pubkey_config = FALSE;
6963 c_write_str(ssh, "Unable to load private key (");
6964 c_write_str(ssh, error);
6965 c_write_str(ssh, ")\r\n");
6966 s->tried_pubkey_config = TRUE;
6968 /* Send a spurious AUTH_NONE to return to the top. */
6969 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6970 ssh2_pkt_addstring(s->pktout, s->username);
6971 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6972 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6973 ssh2_pkt_send(ssh, s->pktout);
6974 s->type = AUTH_TYPE_NONE;
6976 unsigned char *pkblob, *sigblob, *sigdata;
6977 int pkblob_len, sigblob_len, sigdata_len;
6981 * We have loaded the private key and the server
6982 * has announced that it's willing to accept it.
6983 * Hallelujah. Generate a signature and send it.
6985 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6986 ssh2_pkt_addstring(s->pktout, s->username);
6987 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6988 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6989 ssh2_pkt_addbool(s->pktout, TRUE);
6990 ssh2_pkt_addstring(s->pktout, key->alg->name);
6991 pkblob = key->alg->public_blob(key->data, &pkblob_len);
6992 ssh2_pkt_addstring_start(s->pktout);
6993 ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
6996 * The data to be signed is:
7000 * followed by everything so far placed in the
7003 sigdata_len = s->pktout->length - 5 + 4 + 20;
7004 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
7006 sigdata = snewn(sigdata_len, unsigned char);
7008 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
7009 PUT_32BIT(sigdata+p, 20);
7012 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
7013 memcpy(sigdata+p, s->pktout->data + 5,
7014 s->pktout->length - 5);
7015 p += s->pktout->length - 5;
7016 assert(p == sigdata_len);
7017 sigblob = key->alg->sign(key->data, (char *)sigdata,
7018 sigdata_len, &sigblob_len);
7019 ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
7020 sigblob, sigblob_len);
7025 ssh2_pkt_send(ssh, s->pktout);
7026 s->type = AUTH_TYPE_PUBLICKEY;
7027 key->alg->freekey(key->data);
7029 } else if (s->method == AUTH_PASSWORD) {
7031 * We pad out the password packet to 256 bytes to make
7032 * it harder for an attacker to find the length of the
7035 * Anyone using a password longer than 256 bytes
7036 * probably doesn't have much to worry about from
7037 * people who find out how long their password is!
7039 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
7040 s->pktout->forcepad = 256;
7041 ssh2_pkt_addstring(s->pktout, s->username);
7042 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
7043 ssh2_pkt_addstring(s->pktout, "password");
7044 ssh2_pkt_addbool(s->pktout, FALSE);
7045 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
7046 ssh2_pkt_addstring(s->pktout, s->password);
7047 memset(s->password, 0, sizeof(s->password));
7048 end_log_omission(ssh, s->pktout);
7049 ssh2_pkt_send(ssh, s->pktout);
7050 logevent("Sent password");
7051 s->type = AUTH_TYPE_PASSWORD;
7052 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
7053 if (s->curr_prompt == 0) {
7054 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
7055 s->pktout->forcepad = 256;
7056 ssh2_pkt_adduint32(s->pktout, s->num_prompts);
7058 if (s->need_pw) { /* only add pw if we just got one! */
7059 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
7060 ssh2_pkt_addstring(s->pktout, s->password);
7061 memset(s->password, 0, sizeof(s->password));
7062 end_log_omission(ssh, s->pktout);
7065 if (s->curr_prompt >= s->num_prompts) {
7066 ssh2_pkt_send(ssh, s->pktout);
7069 * If there are prompts remaining, we set
7070 * `gotit' so that we won't attempt to get
7071 * another packet. Then we go back round the
7072 * loop and will end up retrieving another
7073 * prompt out of the existing packet. Funky or
7078 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
7080 c_write_str(ssh, "No supported authentication methods"
7081 " left to try!\r\n");
7082 logevent("No supported authentications offered."
7084 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
7085 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
7086 ssh2_pkt_addstring(s->pktout, "No supported authentication"
7087 " methods available");
7088 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
7089 ssh2_pkt_send_noqueue(ssh, s->pktout);
7090 ssh->close_expected = TRUE;
7091 ssh_closing((Plug)ssh, NULL, 0, 0);
7095 } while (!s->we_are_in);
7098 * Now we're authenticated for the connection protocol. The
7099 * connection protocol will automatically have started at this
7100 * point; there's no need to send SERVICE_REQUEST.
7103 ssh->channels = newtree234(ssh_channelcmp);
7106 * Set up handlers for some connection protocol messages, so we
7107 * don't have to handle them repeatedly in this coroutine.
7109 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
7110 ssh2_msg_channel_window_adjust;
7111 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
7112 ssh2_msg_global_request;
7115 * Create the main session channel.
7117 if (!ssh->cfg.ssh_no_shell) {
7118 ssh->mainchan = snew(struct ssh_channel);
7119 ssh->mainchan->ssh = ssh;
7120 ssh->mainchan->localid = alloc_channel_id(ssh);
7121 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
7122 ssh2_pkt_addstring(s->pktout, "session");
7123 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
7124 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
7125 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
7126 ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT); /* our max pkt size */
7127 ssh2_pkt_send(ssh, s->pktout);
7128 crWaitUntilV(pktin);
7129 if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
7130 bombout(("Server refused to open a session"));
7132 /* FIXME: error data comes back in FAILURE packet */
7134 if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
7135 bombout(("Server's channel confirmation cited wrong channel"));
7138 ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
7139 ssh->mainchan->halfopen = FALSE;
7140 ssh->mainchan->type = CHAN_MAINSESSION;
7141 ssh->mainchan->closes = 0;
7142 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
7143 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
7144 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
7145 add234(ssh->channels, ssh->mainchan);
7146 update_specials_menu(ssh->frontend);
7147 logevent("Opened channel for session");
7149 ssh->mainchan = NULL;
7152 * Now we have a channel, make dispatch table entries for
7153 * general channel-based messages.
7155 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
7156 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
7157 ssh2_msg_channel_data;
7158 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
7159 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
7160 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
7161 ssh2_msg_channel_open_confirmation;
7162 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
7163 ssh2_msg_channel_open_failure;
7164 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
7165 ssh2_msg_channel_request;
7166 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
7167 ssh2_msg_channel_open;
7170 * Potentially enable X11 forwarding.
7172 if (ssh->mainchan && ssh->cfg.x11_forward) {
7173 char proto[20], data[64];
7174 logevent("Requesting X11 forwarding");
7175 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
7176 data, sizeof(data), ssh->cfg.x11_auth);
7177 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
7178 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7179 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7180 ssh2_pkt_addstring(s->pktout, "x11-req");
7181 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7182 ssh2_pkt_addbool(s->pktout, 0); /* many connections */
7183 ssh2_pkt_addstring(s->pktout, proto);
7184 ssh2_pkt_addstring(s->pktout, data);
7185 ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
7186 ssh2_pkt_send(ssh, s->pktout);
7188 crWaitUntilV(pktin);
7190 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7191 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
7192 bombout(("Unexpected response to X11 forwarding request:"
7193 " packet type %d", pktin->type));
7196 logevent("X11 forwarding refused");
7198 logevent("X11 forwarding enabled");
7199 ssh->X11_fwd_enabled = TRUE;
7204 * Enable port forwardings.
7206 ssh_setup_portfwd(ssh, &ssh->cfg);
7209 * Potentially enable agent forwarding.
7211 if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
7212 logevent("Requesting OpenSSH-style agent forwarding");
7213 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7214 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7215 ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com");
7216 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7217 ssh2_pkt_send(ssh, s->pktout);
7219 crWaitUntilV(pktin);
7221 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7222 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
7223 bombout(("Unexpected response to agent forwarding request:"
7224 " packet type %d", pktin->type));
7227 logevent("Agent forwarding refused");
7229 logevent("Agent forwarding enabled");
7230 ssh->agentfwd_enabled = TRUE;
7235 * Now allocate a pty for the session.
7237 if (ssh->mainchan && !ssh->cfg.nopty) {
7238 /* Unpick the terminal-speed string. */
7239 /* XXX perhaps we should allow no speeds to be sent. */
7240 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
7241 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
7242 /* Build the pty request. */
7243 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7244 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
7245 ssh2_pkt_addstring(s->pktout, "pty-req");
7246 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7247 ssh2_pkt_addstring(s->pktout, ssh->cfg.termtype);
7248 ssh2_pkt_adduint32(s->pktout, ssh->term_width);
7249 ssh2_pkt_adduint32(s->pktout, ssh->term_height);
7250 ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
7251 ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
7252 ssh2_pkt_addstring_start(s->pktout);
7253 ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
7254 ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
7255 ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
7256 ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
7257 ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
7258 ssh2_pkt_send(ssh, s->pktout);
7259 ssh->state = SSH_STATE_INTERMED;
7261 crWaitUntilV(pktin);
7263 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7264 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
7265 bombout(("Unexpected response to pty request:"
7266 " packet type %d", pktin->type));
7269 c_write_str(ssh, "Server refused to allocate pty\r\n");
7270 ssh->editing = ssh->echoing = 1;
7272 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7273 ssh->ospeed, ssh->ispeed);
7276 ssh->editing = ssh->echoing = 1;
7280 * Send environment variables.
7282 * Simplest thing here is to send all the requests at once, and
7283 * then wait for a whole bunch of successes or failures.
7285 if (ssh->mainchan && *ssh->cfg.environmt) {
7286 char *e = ssh->cfg.environmt;
7287 char *var, *varend, *val;
7293 while (*e && *e != '\t') e++;
7295 if (*e == '\t') e++;
7300 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7301 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7302 ssh2_pkt_addstring(s->pktout, "env");
7303 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7304 ssh2_pkt_addstring_start(s->pktout);
7305 ssh2_pkt_addstring_data(s->pktout, var, varend-var);
7306 ssh2_pkt_addstring(s->pktout, val);
7307 ssh2_pkt_send(ssh, s->pktout);
7312 logeventf(ssh, "Sent %d environment variables", s->num_env);
7315 s->env_left = s->num_env;
7317 while (s->env_left > 0) {
7318 crWaitUntilV(pktin);
7320 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7321 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
7322 bombout(("Unexpected response to environment request:"
7323 " packet type %d", pktin->type));
7333 if (s->env_ok == s->num_env) {
7334 logevent("All environment variables successfully set");
7335 } else if (s->env_ok == 0) {
7336 logevent("All environment variables refused");
7337 c_write_str(ssh, "Server refused to set environment variables\r\n");
7339 logeventf(ssh, "%d environment variables refused",
7340 s->num_env - s->env_ok);
7341 c_write_str(ssh, "Server refused to set all environment variables\r\n");
7346 * Start a shell or a remote command. We may have to attempt
7347 * this twice if the config data has provided a second choice
7350 if (ssh->mainchan) while (1) {
7354 if (ssh->fallback_cmd) {
7355 subsys = ssh->cfg.ssh_subsys2;
7356 cmd = ssh->cfg.remote_cmd_ptr2;
7358 subsys = ssh->cfg.ssh_subsys;
7359 cmd = ssh->cfg.remote_cmd_ptr;
7360 if (!cmd) cmd = ssh->cfg.remote_cmd;
7363 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7364 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
7366 ssh2_pkt_addstring(s->pktout, "subsystem");
7367 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7368 ssh2_pkt_addstring(s->pktout, cmd);
7370 ssh2_pkt_addstring(s->pktout, "exec");
7371 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7372 ssh2_pkt_addstring(s->pktout, cmd);
7374 ssh2_pkt_addstring(s->pktout, "shell");
7375 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7377 ssh2_pkt_send(ssh, s->pktout);
7379 crWaitUntilV(pktin);
7381 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7382 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
7383 bombout(("Unexpected response to shell/command request:"
7384 " packet type %d", pktin->type));
7388 * We failed to start the command. If this is the
7389 * fallback command, we really are finished; if it's
7390 * not, and if the fallback command exists, try falling
7391 * back to it before complaining.
7393 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
7394 logevent("Primary command failed; attempting fallback");
7395 ssh->fallback_cmd = TRUE;
7398 bombout(("Server refused to start a shell/command"));
7401 logevent("Started a shell/command");
7406 ssh->state = SSH_STATE_SESSION;
7407 if (ssh->size_needed)
7408 ssh_size(ssh, ssh->term_width, ssh->term_height);
7409 if (ssh->eof_needed)
7410 ssh_special(ssh, TS_EOF);
7416 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
7421 s->try_send = FALSE;
7425 * _All_ the connection-layer packets we expect to
7426 * receive are now handled by the dispatch table.
7427 * Anything that reaches here must be bogus.
7430 bombout(("Strange packet received: type %d", pktin->type));
7432 } else if (ssh->mainchan) {
7434 * We have spare data. Add it to the channel buffer.
7436 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
7441 struct ssh_channel *c;
7443 * Try to send data on all channels if we can.
7445 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++)
7446 ssh2_try_send_and_unthrottle(c);
7454 * Handlers for SSH-2 messages that might arrive at any moment.
7456 static void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
7458 /* log reason code in disconnect message */
7460 int nowlen, reason, msglen;
7462 reason = ssh_pkt_getuint32(pktin);
7463 ssh_pkt_getstring(pktin, &msg, &msglen);
7465 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
7466 buf = dupprintf("Received disconnect message (%s)",
7467 ssh2_disconnect_reasons[reason]);
7469 buf = dupprintf("Received disconnect message (unknown"
7470 " type %d)", reason);
7474 buf = dupprintf("Disconnection message text: %n%.*s",
7475 &nowlen, msglen, msg);
7477 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7479 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
7480 ssh2_disconnect_reasons[reason] : "unknown",
7485 static void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
7487 /* log the debug message */
7492 /* XXX maybe we should actually take notice of this */
7493 always_display = ssh2_pkt_getbool(pktin);
7494 ssh_pkt_getstring(pktin, &msg, &msglen);
7496 logeventf(ssh, "Remote debug message: %.*s", msglen, msg);
7499 static void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
7501 struct Packet *pktout;
7502 pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
7503 ssh2_pkt_adduint32(pktout, pktin->sequence);
7505 * UNIMPLEMENTED messages MUST appear in the same order as the
7506 * messages they respond to. Hence, never queue them.
7508 ssh2_pkt_send_noqueue(ssh, pktout);
7512 * Handle the top-level SSH-2 protocol.
7514 static void ssh2_protocol_setup(Ssh ssh)
7519 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7521 for (i = 0; i < 256; i++)
7522 ssh->packet_dispatch[i] = ssh2_msg_something_unimplemented;
7525 * Any message we actually understand, we set to NULL so that
7526 * the coroutines will get it.
7528 ssh->packet_dispatch[SSH2_MSG_UNIMPLEMENTED] = NULL;
7529 ssh->packet_dispatch[SSH2_MSG_SERVICE_REQUEST] = NULL;
7530 ssh->packet_dispatch[SSH2_MSG_SERVICE_ACCEPT] = NULL;
7531 ssh->packet_dispatch[SSH2_MSG_KEXINIT] = NULL;
7532 ssh->packet_dispatch[SSH2_MSG_NEWKEYS] = NULL;
7533 ssh->packet_dispatch[SSH2_MSG_KEXDH_INIT] = NULL;
7534 ssh->packet_dispatch[SSH2_MSG_KEXDH_REPLY] = NULL;
7535 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7536 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7537 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_INIT] = NULL;
7538 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REPLY] = NULL;
7539 ssh->packet_dispatch[SSH2_MSG_USERAUTH_REQUEST] = NULL;
7540 ssh->packet_dispatch[SSH2_MSG_USERAUTH_FAILURE] = NULL;
7541 ssh->packet_dispatch[SSH2_MSG_USERAUTH_SUCCESS] = NULL;
7542 ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
7543 ssh->packet_dispatch[SSH2_MSG_USERAUTH_PK_OK] = NULL;
7544 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7545 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7546 ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_RESPONSE] = NULL;
7547 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] = NULL;
7548 ssh->packet_dispatch[SSH2_MSG_REQUEST_SUCCESS] = NULL;
7549 ssh->packet_dispatch[SSH2_MSG_REQUEST_FAILURE] = NULL;
7550 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] = NULL;
7551 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] = NULL;
7552 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] = NULL;
7553 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] = NULL;
7554 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] = NULL;
7555 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] = NULL;
7556 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = NULL;
7557 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = NULL;
7558 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] = NULL;
7559 ssh->packet_dispatch[SSH2_MSG_CHANNEL_SUCCESS] = NULL;
7560 ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] = NULL;
7563 * These special message types we install handlers for.
7565 ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
7566 ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with SSH-1 */
7567 ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
7570 static void ssh2_timer(void *ctx, long now)
7574 if (!ssh->kex_in_progress && ssh->cfg.ssh_rekey_time != 0 &&
7575 now - ssh->next_rekey >= 0) {
7576 do_ssh2_transport(ssh, "timeout", -1, NULL);
7580 static void ssh2_protocol(Ssh ssh, void *vin, int inlen,
7581 struct Packet *pktin)
7583 unsigned char *in = (unsigned char *)vin;
7584 if (ssh->state == SSH_STATE_CLOSED)
7588 ssh->incoming_data_size += pktin->encrypted_len;
7589 if (!ssh->kex_in_progress &&
7590 ssh->max_data_size != 0 &&
7591 ssh->incoming_data_size > ssh->max_data_size)
7592 do_ssh2_transport(ssh, "too much data received", -1, NULL);
7595 if (pktin && ssh->packet_dispatch[pktin->type]) {
7596 ssh->packet_dispatch[pktin->type](ssh, pktin);
7600 if (!ssh->protocol_initial_phase_done ||
7601 (pktin && pktin->type >= 20 && pktin->type < 50)) {
7602 if (do_ssh2_transport(ssh, in, inlen, pktin) &&
7603 !ssh->protocol_initial_phase_done) {
7604 ssh->protocol_initial_phase_done = TRUE;
7606 * Allow authconn to initialise itself.
7608 do_ssh2_authconn(ssh, NULL, 0, NULL);
7611 do_ssh2_authconn(ssh, in, inlen, pktin);
7616 * Called to set up the connection.
7618 * Returns an error message, or NULL on success.
7620 static const char *ssh_init(void *frontend_handle, void **backend_handle,
7622 char *host, int port, char **realhost, int nodelay,
7628 ssh = snew(struct ssh_tag);
7629 ssh->cfg = *cfg; /* STRUCTURE COPY */
7630 ssh->version = 0; /* when not ready yet */
7633 ssh->v1_cipher_ctx = NULL;
7634 ssh->crcda_ctx = NULL;
7635 ssh->cscipher = NULL;
7636 ssh->cs_cipher_ctx = NULL;
7637 ssh->sccipher = NULL;
7638 ssh->sc_cipher_ctx = NULL;
7640 ssh->cs_mac_ctx = NULL;
7642 ssh->sc_mac_ctx = NULL;
7644 ssh->cs_comp_ctx = NULL;
7646 ssh->sc_comp_ctx = NULL;
7648 ssh->kex_ctx = NULL;
7649 ssh->hostkey = NULL;
7651 ssh->close_expected = FALSE;
7652 ssh->state = SSH_STATE_PREPACKET;
7653 ssh->size_needed = FALSE;
7654 ssh->eof_needed = FALSE;
7657 ssh->deferred_send_data = NULL;
7658 ssh->deferred_len = 0;
7659 ssh->deferred_size = 0;
7660 ssh->fallback_cmd = 0;
7662 ssh->x11auth = NULL;
7663 ssh->v1_compressing = FALSE;
7664 ssh->v2_outgoing_sequence = 0;
7665 ssh->ssh1_rdpkt_crstate = 0;
7666 ssh->ssh2_rdpkt_crstate = 0;
7667 ssh->do_ssh_init_crstate = 0;
7668 ssh->ssh_gotdata_crstate = 0;
7669 ssh->do_ssh1_connection_crstate = 0;
7670 ssh->do_ssh1_login_crstate = 0;
7671 ssh->do_ssh2_transport_crstate = 0;
7672 ssh->do_ssh2_authconn_crstate = 0;
7673 ssh->do_ssh_init_state = NULL;
7674 ssh->do_ssh1_login_state = NULL;
7675 ssh->do_ssh2_transport_state = NULL;
7676 ssh->do_ssh2_authconn_state = NULL;
7677 ssh->mainchan = NULL;
7678 ssh->throttled_all = 0;
7679 ssh->v1_stdout_throttling = 0;
7681 ssh->queuelen = ssh->queuesize = 0;
7682 ssh->queueing = FALSE;
7683 ssh->qhead = ssh->qtail = NULL;
7684 ssh->deferred_rekey_reason = NULL;
7685 bufchain_init(&ssh->queued_incoming_data);
7686 ssh->frozen = FALSE;
7688 *backend_handle = ssh;
7691 if (crypto_startup() == 0)
7692 return "Microsoft high encryption pack not installed!";
7695 ssh->frontend = frontend_handle;
7696 ssh->term_width = ssh->cfg.width;
7697 ssh->term_height = ssh->cfg.height;
7699 ssh->channels = NULL;
7700 ssh->rportfwds = NULL;
7701 ssh->portfwds = NULL;
7706 ssh->v1_throttle_count = 0;
7707 ssh->overall_bufsize = 0;
7708 ssh->fallback_cmd = 0;
7710 ssh->protocol = NULL;
7712 ssh->protocol_initial_phase_done = FALSE;
7716 ssh->incoming_data_size = ssh->outgoing_data_size =
7717 ssh->deferred_data_size = 0L;
7718 ssh->max_data_size = parse_blocksize(ssh->cfg.ssh_rekey_data);
7719 ssh->kex_in_progress = FALSE;
7721 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
7730 static void ssh_free(void *handle)
7732 Ssh ssh = (Ssh) handle;
7733 struct ssh_channel *c;
7734 struct ssh_rportfwd *pf;
7736 if (ssh->v1_cipher_ctx)
7737 ssh->cipher->free_context(ssh->v1_cipher_ctx);
7738 if (ssh->cs_cipher_ctx)
7739 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
7740 if (ssh->sc_cipher_ctx)
7741 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
7742 if (ssh->cs_mac_ctx)
7743 ssh->csmac->free_context(ssh->cs_mac_ctx);
7744 if (ssh->sc_mac_ctx)
7745 ssh->scmac->free_context(ssh->sc_mac_ctx);
7746 if (ssh->cs_comp_ctx) {
7748 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
7750 zlib_compress_cleanup(ssh->cs_comp_ctx);
7752 if (ssh->sc_comp_ctx) {
7754 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
7756 zlib_decompress_cleanup(ssh->sc_comp_ctx);
7759 dh_cleanup(ssh->kex_ctx);
7760 sfree(ssh->savedhost);
7762 while (ssh->queuelen-- > 0)
7763 ssh_free_packet(ssh->queue[ssh->queuelen]);
7766 while (ssh->qhead) {
7767 struct queued_handler *qh = ssh->qhead;
7768 ssh->qhead = qh->next;
7771 ssh->qhead = ssh->qtail = NULL;
7773 if (ssh->channels) {
7774 while ((c = delpos234(ssh->channels, 0)) != NULL) {
7777 if (c->u.x11.s != NULL)
7778 x11_close(c->u.x11.s);
7781 if (c->u.pfd.s != NULL)
7782 pfd_close(c->u.pfd.s);
7787 freetree234(ssh->channels);
7788 ssh->channels = NULL;
7791 if (ssh->rportfwds) {
7792 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
7794 freetree234(ssh->rportfwds);
7795 ssh->rportfwds = NULL;
7797 sfree(ssh->deferred_send_data);
7799 x11_free_auth(ssh->x11auth);
7800 sfree(ssh->do_ssh_init_state);
7801 sfree(ssh->do_ssh1_login_state);
7802 sfree(ssh->do_ssh2_transport_state);
7803 sfree(ssh->do_ssh2_authconn_state);
7804 if (ssh->crcda_ctx) {
7805 crcda_free_context(ssh->crcda_ctx);
7806 ssh->crcda_ctx = NULL;
7809 ssh_do_close(ssh, TRUE);
7810 expire_timer_context(ssh);
7812 pinger_free(ssh->pinger);
7813 bufchain_clear(&ssh->queued_incoming_data);
7820 * Reconfigure the SSH backend.
7822 static void ssh_reconfig(void *handle, Config *cfg)
7824 Ssh ssh = (Ssh) handle;
7825 char *rekeying = NULL, rekey_mandatory = FALSE;
7826 unsigned long old_max_data_size;
7828 pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
7829 ssh_setup_portfwd(ssh, cfg);
7831 if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
7832 cfg->ssh_rekey_time != 0) {
7833 long new_next = ssh->last_rekey + cfg->ssh_rekey_time*60*TICKSPERSEC;
7834 long now = GETTICKCOUNT();
7836 if (new_next - now < 0) {
7837 rekeying = "timeout shortened";
7839 ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh);
7843 old_max_data_size = ssh->max_data_size;
7844 ssh->max_data_size = parse_blocksize(cfg->ssh_rekey_data);
7845 if (old_max_data_size != ssh->max_data_size &&
7846 ssh->max_data_size != 0) {
7847 if (ssh->outgoing_data_size > ssh->max_data_size ||
7848 ssh->incoming_data_size > ssh->max_data_size)
7849 rekeying = "data limit lowered";
7852 if (ssh->cfg.compression != cfg->compression) {
7853 rekeying = "compression setting changed";
7854 rekey_mandatory = TRUE;
7857 if (ssh->cfg.ssh2_des_cbc != cfg->ssh2_des_cbc ||
7858 memcmp(ssh->cfg.ssh_cipherlist, cfg->ssh_cipherlist,
7859 sizeof(ssh->cfg.ssh_cipherlist))) {
7860 rekeying = "cipher settings changed";
7861 rekey_mandatory = TRUE;
7864 ssh->cfg = *cfg; /* STRUCTURE COPY */
7867 if (!ssh->kex_in_progress) {
7868 do_ssh2_transport(ssh, rekeying, -1, NULL);
7869 } else if (rekey_mandatory) {
7870 ssh->deferred_rekey_reason = rekeying;
7876 * Called to send data down the Telnet connection.
7878 static int ssh_send(void *handle, char *buf, int len)
7880 Ssh ssh = (Ssh) handle;
7882 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
7885 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
7887 return ssh_sendbuffer(ssh);
7891 * Called to query the current amount of buffered stdin data.
7893 static int ssh_sendbuffer(void *handle)
7895 Ssh ssh = (Ssh) handle;
7898 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
7902 * If the SSH socket itself has backed up, add the total backup
7903 * size on that to any individual buffer on the stdin channel.
7906 if (ssh->throttled_all)
7907 override_value = ssh->overall_bufsize;
7909 if (ssh->version == 1) {
7910 return override_value;
7911 } else if (ssh->version == 2) {
7912 if (!ssh->mainchan || ssh->mainchan->closes > 0)
7913 return override_value;
7915 return (override_value +
7916 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
7923 * Called to set the size of the window from SSH's POV.
7925 static void ssh_size(void *handle, int width, int height)
7927 Ssh ssh = (Ssh) handle;
7928 struct Packet *pktout;
7930 ssh->term_width = width;
7931 ssh->term_height = height;
7933 switch (ssh->state) {
7934 case SSH_STATE_BEFORE_SIZE:
7935 case SSH_STATE_PREPACKET:
7936 case SSH_STATE_CLOSED:
7937 break; /* do nothing */
7938 case SSH_STATE_INTERMED:
7939 ssh->size_needed = TRUE; /* buffer for later */
7941 case SSH_STATE_SESSION:
7942 if (!ssh->cfg.nopty) {
7943 if (ssh->version == 1) {
7944 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
7945 PKT_INT, ssh->term_height,
7946 PKT_INT, ssh->term_width,
7947 PKT_INT, 0, PKT_INT, 0, PKT_END);
7948 } else if (ssh->mainchan) {
7949 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7950 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7951 ssh2_pkt_addstring(pktout, "window-change");
7952 ssh2_pkt_addbool(pktout, 0);
7953 ssh2_pkt_adduint32(pktout, ssh->term_width);
7954 ssh2_pkt_adduint32(pktout, ssh->term_height);
7955 ssh2_pkt_adduint32(pktout, 0);
7956 ssh2_pkt_adduint32(pktout, 0);
7957 ssh2_pkt_send(ssh, pktout);
7965 * Return a list of the special codes that make sense in this
7968 static const struct telnet_special *ssh_get_specials(void *handle)
7970 static const struct telnet_special ssh1_ignore_special[] = {
7971 {"IGNORE message", TS_NOP}
7973 static const struct telnet_special ssh2_transport_specials[] = {
7974 {"IGNORE message", TS_NOP},
7975 {"Repeat key exchange", TS_REKEY},
7977 static const struct telnet_special ssh2_session_specials[] = {
7980 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7981 * They include all the ISO C signals, but are a subset of the POSIX
7982 * required signals. */
7983 {"SIGINT (Interrupt)", TS_SIGINT},
7984 {"SIGTERM (Terminate)", TS_SIGTERM},
7985 {"SIGKILL (Kill)", TS_SIGKILL},
7986 {"SIGQUIT (Quit)", TS_SIGQUIT},
7987 {"SIGHUP (Hangup)", TS_SIGHUP},
7988 {"More signals", TS_SUBMENU},
7989 {"SIGABRT", TS_SIGABRT}, {"SIGALRM", TS_SIGALRM},
7990 {"SIGFPE", TS_SIGFPE}, {"SIGILL", TS_SIGILL},
7991 {"SIGPIPE", TS_SIGPIPE}, {"SIGSEGV", TS_SIGSEGV},
7992 {"SIGUSR1", TS_SIGUSR1}, {"SIGUSR2", TS_SIGUSR2},
7995 static const struct telnet_special specials_end[] = {
7998 /* XXX review this length for any changes: */
7999 static struct telnet_special ssh_specials[lenof(ssh2_transport_specials) +
8000 lenof(ssh2_session_specials) +
8001 lenof(specials_end)];
8002 Ssh ssh = (Ssh) handle;
8004 #define ADD_SPECIALS(name) \
8006 assert((i + lenof(name)) <= lenof(ssh_specials)); \
8007 memcpy(&ssh_specials[i], name, sizeof name); \
8011 if (ssh->version == 1) {
8012 /* Don't bother offering IGNORE if we've decided the remote
8013 * won't cope with it, since we wouldn't bother sending it if
8015 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
8016 ADD_SPECIALS(ssh1_ignore_special);
8017 } else if (ssh->version == 2) {
8018 ADD_SPECIALS(ssh2_transport_specials);
8020 ADD_SPECIALS(ssh2_session_specials);
8021 } /* else we're not ready yet */
8024 ADD_SPECIALS(specials_end);
8025 return ssh_specials;
8033 * Send Telnet special codes. TS_EOF is useful for `plink', so you
8034 * can send an EOF and collect resulting output (e.g. `plink
8037 static void ssh_special(void *handle, Telnet_Special code)
8039 Ssh ssh = (Ssh) handle;
8040 struct Packet *pktout;
8042 if (code == TS_EOF) {
8043 if (ssh->state != SSH_STATE_SESSION) {
8045 * Buffer the EOF in case we are pre-SESSION, so we can
8046 * send it as soon as we reach SESSION.
8049 ssh->eof_needed = TRUE;
8052 if (ssh->version == 1) {
8053 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
8054 } else if (ssh->mainchan) {
8055 struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
8056 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
8057 ssh2_pkt_send(ssh, pktout);
8059 logevent("Sent EOF message");
8060 } else if (code == TS_PING || code == TS_NOP) {
8061 if (ssh->state == SSH_STATE_CLOSED
8062 || ssh->state == SSH_STATE_PREPACKET) return;
8063 if (ssh->version == 1) {
8064 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
8065 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
8067 pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
8068 ssh2_pkt_addstring_start(pktout);
8069 ssh2_pkt_send_noqueue(ssh, pktout);
8071 } else if (code == TS_REKEY) {
8072 if (!ssh->kex_in_progress && ssh->version == 2) {
8073 do_ssh2_transport(ssh, "at user request", -1, NULL);
8075 } else if (code == TS_BRK) {
8076 if (ssh->state == SSH_STATE_CLOSED
8077 || ssh->state == SSH_STATE_PREPACKET) return;
8078 if (ssh->version == 1) {
8079 logevent("Unable to send BREAK signal in SSH-1");
8080 } else if (ssh->mainchan) {
8081 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
8082 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
8083 ssh2_pkt_addstring(pktout, "break");
8084 ssh2_pkt_addbool(pktout, 0);
8085 ssh2_pkt_adduint32(pktout, 0); /* default break length */
8086 ssh2_pkt_send(ssh, pktout);
8089 /* Is is a POSIX signal? */
8090 char *signame = NULL;
8091 if (code == TS_SIGABRT) signame = "ABRT";
8092 if (code == TS_SIGALRM) signame = "ALRM";
8093 if (code == TS_SIGFPE) signame = "FPE";
8094 if (code == TS_SIGHUP) signame = "HUP";
8095 if (code == TS_SIGILL) signame = "ILL";
8096 if (code == TS_SIGINT) signame = "INT";
8097 if (code == TS_SIGKILL) signame = "KILL";
8098 if (code == TS_SIGPIPE) signame = "PIPE";
8099 if (code == TS_SIGQUIT) signame = "QUIT";
8100 if (code == TS_SIGSEGV) signame = "SEGV";
8101 if (code == TS_SIGTERM) signame = "TERM";
8102 if (code == TS_SIGUSR1) signame = "USR1";
8103 if (code == TS_SIGUSR2) signame = "USR2";
8104 /* The SSH-2 protocol does in principle support arbitrary named
8105 * signals, including signame@domain, but we don't support those. */
8107 /* It's a signal. */
8108 if (ssh->version == 2 && ssh->mainchan) {
8109 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
8110 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
8111 ssh2_pkt_addstring(pktout, "signal");
8112 ssh2_pkt_addbool(pktout, 0);
8113 ssh2_pkt_addstring(pktout, signame);
8114 ssh2_pkt_send(ssh, pktout);
8115 logeventf(ssh, "Sent signal SIG%s", signame);
8118 /* Never heard of it. Do nothing */
8123 void *new_sock_channel(void *handle, Socket s)
8125 Ssh ssh = (Ssh) handle;
8126 struct ssh_channel *c;
8127 c = snew(struct ssh_channel);
8132 c->localid = alloc_channel_id(ssh);
8134 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
8136 bufchain_init(&c->v.v2.outbuffer);
8137 add234(ssh->channels, c);
8143 * This is called when stdout/stderr (the entity to which
8144 * from_backend sends data) manages to clear some backlog.
8146 static void ssh_unthrottle(void *handle, int bufsize)
8148 Ssh ssh = (Ssh) handle;
8149 if (ssh->version == 1) {
8150 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
8151 ssh->v1_stdout_throttling = 0;
8152 ssh1_throttle(ssh, -1);
8155 if (ssh->mainchan && ssh->mainchan->closes == 0)
8156 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
8160 void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
8162 struct ssh_channel *c = (struct ssh_channel *)channel;
8164 struct Packet *pktout;
8166 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
8168 if (ssh->version == 1) {
8169 send_packet(ssh, SSH1_MSG_PORT_OPEN,
8170 PKT_INT, c->localid,
8173 /* PKT_STR, <org:orgport>, */
8176 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
8177 ssh2_pkt_addstring(pktout, "direct-tcpip");
8178 ssh2_pkt_adduint32(pktout, c->localid);
8179 c->v.v2.locwindow = OUR_V2_WINSIZE;
8180 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
8181 ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
8182 ssh2_pkt_addstring(pktout, hostname);
8183 ssh2_pkt_adduint32(pktout, port);
8185 * We make up values for the originator data; partly it's
8186 * too much hassle to keep track, and partly I'm not
8187 * convinced the server should be told details like that
8188 * about my local network configuration.
8190 ssh2_pkt_addstring(pktout, "client-side-connection");
8191 ssh2_pkt_adduint32(pktout, 0);
8192 ssh2_pkt_send(ssh, pktout);
8196 static Socket ssh_socket(void *handle)
8198 Ssh ssh = (Ssh) handle;
8202 static int ssh_sendok(void *handle)
8204 Ssh ssh = (Ssh) handle;
8205 return ssh->send_ok;
8208 static int ssh_ldisc(void *handle, int option)
8210 Ssh ssh = (Ssh) handle;
8211 if (option == LD_ECHO)
8212 return ssh->echoing;
8213 if (option == LD_EDIT)
8214 return ssh->editing;
8218 static void ssh_provide_ldisc(void *handle, void *ldisc)
8220 Ssh ssh = (Ssh) handle;
8224 static void ssh_provide_logctx(void *handle, void *logctx)
8226 Ssh ssh = (Ssh) handle;
8227 ssh->logctx = logctx;
8230 static int ssh_return_exitcode(void *handle)
8232 Ssh ssh = (Ssh) handle;
8236 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
8240 * cfg_info for SSH is the currently running version of the
8241 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8243 static int ssh_cfg_info(void *handle)
8245 Ssh ssh = (Ssh) handle;
8246 return ssh->version;
8250 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8251 * that fails. This variable is the means by which scp.c can reach
8252 * into the SSH code and find out which one it got.
8254 extern int ssh_fallback_cmd(void *handle)
8256 Ssh ssh = (Ssh) handle;
8257 return ssh->fallback_cmd;
8260 Backend ssh_backend = {
8270 ssh_return_exitcode,