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_DHGROUP1 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_PUBLICKEY 0x0010
110 #define SSH2_PKTCTX_PASSWORD 0x0020
111 #define SSH2_PKTCTX_KBDINTER 0x0040
112 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
114 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
130 static const char *const ssh2_disconnect_reasons[] = {
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
149 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
154 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
157 * Various remote-bug flags.
159 #define BUG_CHOKES_ON_SSH1_IGNORE 1
160 #define BUG_SSH2_HMAC 2
161 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
162 #define BUG_CHOKES_ON_RSA 8
163 #define BUG_SSH2_RSA_PADDING 16
164 #define BUG_SSH2_DERIVEKEY 32
165 #define BUG_SSH2_DH_GEX 64
166 #define BUG_SSH2_PK_SESSIONID 128
168 #define translate(x) if (type == x) return #x
169 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
170 static char *ssh1_pkt_type(int type)
172 translate(SSH1_MSG_DISCONNECT);
173 translate(SSH1_SMSG_PUBLIC_KEY);
174 translate(SSH1_CMSG_SESSION_KEY);
175 translate(SSH1_CMSG_USER);
176 translate(SSH1_CMSG_AUTH_RSA);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
179 translate(SSH1_CMSG_AUTH_PASSWORD);
180 translate(SSH1_CMSG_REQUEST_PTY);
181 translate(SSH1_CMSG_WINDOW_SIZE);
182 translate(SSH1_CMSG_EXEC_SHELL);
183 translate(SSH1_CMSG_EXEC_CMD);
184 translate(SSH1_SMSG_SUCCESS);
185 translate(SSH1_SMSG_FAILURE);
186 translate(SSH1_CMSG_STDIN_DATA);
187 translate(SSH1_SMSG_STDOUT_DATA);
188 translate(SSH1_SMSG_STDERR_DATA);
189 translate(SSH1_CMSG_EOF);
190 translate(SSH1_SMSG_EXIT_STATUS);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
193 translate(SSH1_MSG_CHANNEL_DATA);
194 translate(SSH1_MSG_CHANNEL_CLOSE);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
196 translate(SSH1_SMSG_X11_OPEN);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
198 translate(SSH1_MSG_PORT_OPEN);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
200 translate(SSH1_SMSG_AGENT_OPEN);
201 translate(SSH1_MSG_IGNORE);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
205 translate(SSH1_MSG_DEBUG);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION);
207 translate(SSH1_CMSG_AUTH_TIS);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
210 translate(SSH1_CMSG_AUTH_CCARD);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
215 static char *ssh2_pkt_type(int pkt_ctx, int type)
217 translate(SSH2_MSG_DISCONNECT);
218 translate(SSH2_MSG_IGNORE);
219 translate(SSH2_MSG_UNIMPLEMENTED);
220 translate(SSH2_MSG_DEBUG);
221 translate(SSH2_MSG_SERVICE_REQUEST);
222 translate(SSH2_MSG_SERVICE_ACCEPT);
223 translate(SSH2_MSG_KEXINIT);
224 translate(SSH2_MSG_NEWKEYS);
225 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP1);
226 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP1);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
231 translate(SSH2_MSG_USERAUTH_REQUEST);
232 translate(SSH2_MSG_USERAUTH_FAILURE);
233 translate(SSH2_MSG_USERAUTH_SUCCESS);
234 translate(SSH2_MSG_USERAUTH_BANNER);
235 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
239 translate(SSH2_MSG_GLOBAL_REQUEST);
240 translate(SSH2_MSG_REQUEST_SUCCESS);
241 translate(SSH2_MSG_REQUEST_FAILURE);
242 translate(SSH2_MSG_CHANNEL_OPEN);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
246 translate(SSH2_MSG_CHANNEL_DATA);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
248 translate(SSH2_MSG_CHANNEL_EOF);
249 translate(SSH2_MSG_CHANNEL_CLOSE);
250 translate(SSH2_MSG_CHANNEL_REQUEST);
251 translate(SSH2_MSG_CHANNEL_SUCCESS);
252 translate(SSH2_MSG_CHANNEL_FAILURE);
258 #define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
264 #define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
270 /* Enumeration values for fields in SSH-1 packets */
272 PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM,
273 /* These values are for communicating relevant semantics of
274 * fields to the packet logging code. */
275 PKTT_OTHER, PKTT_PASSWORD, PKTT_DATA
279 * Coroutine mechanics for the sillier bits of the code. If these
280 * macros look impenetrable to you, you might find it helpful to
283 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
285 * which explains the theory behind these macros.
287 * In particular, if you are getting `case expression not constant'
288 * errors when building with MS Visual Studio, this is because MS's
289 * Edit and Continue debugging feature causes their compiler to
290 * violate ANSI C. To disable Edit and Continue debugging:
292 * - right-click ssh.c in the FileView
294 * - select the C/C++ tab and the General category
295 * - under `Debug info:', select anything _other_ than `Program
296 * Database for Edit and Continue'.
298 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
301 if (!ssh->t) ssh->t = snew(struct t); \
303 #define crFinish(z) } *crLine = 0; return (z); }
304 #define crFinishV } *crLine = 0; return; }
305 #define crReturn(z) \
307 *crLine =__LINE__; return (z); case __LINE__:;\
311 *crLine=__LINE__; return; case __LINE__:;\
313 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
314 #define crStopV do{ *crLine = 0; return; }while(0)
315 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
316 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
318 typedef struct ssh_tag *Ssh;
321 static struct Packet *ssh2_pkt_init(int pkt_type);
322 static void ssh2_pkt_addbool(struct Packet *, unsigned char value);
323 static void ssh2_pkt_adduint32(struct Packet *, unsigned long value);
324 static void ssh2_pkt_addstring_start(struct Packet *);
325 static void ssh2_pkt_addstring_str(struct Packet *, char *data);
326 static void ssh2_pkt_addstring_data(struct Packet *, char *data, int len);
327 static void ssh2_pkt_addstring(struct Packet *, char *data);
328 static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
329 static void ssh2_pkt_addmp(struct Packet *, Bignum b);
330 static int ssh2_pkt_construct(Ssh, struct Packet *);
331 static void ssh2_pkt_send(Ssh, struct Packet *);
332 static void ssh2_pkt_send_noqueue(Ssh, struct Packet *);
333 static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
334 struct Packet *pktin);
335 static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
336 struct Packet *pktin);
339 * Buffer management constants. There are several of these for
340 * various different purposes:
342 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
343 * on a local data stream before we throttle the whole SSH
344 * connection (in SSH1 only). Throttling the whole connection is
345 * pretty drastic so we set this high in the hope it won't
348 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
349 * on the SSH connection itself before we defensively throttle
350 * _all_ local data streams. This is pretty drastic too (though
351 * thankfully unlikely in SSH2 since the window mechanism should
352 * ensure that the server never has any need to throttle its end
353 * of the connection), so we set this high as well.
355 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
359 #define SSH1_BUFFER_LIMIT 32768
360 #define SSH_MAX_BACKLOG 32768
361 #define OUR_V2_WINSIZE 16384
363 const static struct ssh_kex *kex_algs[] = {
364 &ssh_diffiehellman_gex,
368 const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
370 static void *nullmac_make_context(void)
374 static void nullmac_free_context(void *handle)
377 static void nullmac_key(void *handle, unsigned char *key)
380 static void nullmac_generate(void *handle, unsigned char *blk, int len,
384 static int nullmac_verify(void *handle, unsigned char *blk, int len,
389 const static struct ssh_mac ssh_mac_none = {
390 nullmac_make_context, nullmac_free_context, nullmac_key,
391 nullmac_generate, nullmac_verify, "none", 0
393 const static struct ssh_mac *macs[] = {
394 &ssh_sha1, &ssh_md5, &ssh_mac_none
396 const static struct ssh_mac *buggymacs[] = {
397 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
400 static void *ssh_comp_none_init(void)
404 static void ssh_comp_none_cleanup(void *handle)
407 static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
408 unsigned char **outblock, int *outlen)
412 static int ssh_comp_none_disable(void *handle)
416 const static struct ssh_compress ssh_comp_none = {
418 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
419 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
420 ssh_comp_none_disable, NULL
422 extern const struct ssh_compress ssh_zlib;
423 const static struct ssh_compress *compressions[] = {
424 &ssh_zlib, &ssh_comp_none
427 enum { /* channel types */
432 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
436 * 2-3-4 tree storing channels.
439 Ssh ssh; /* pointer back to main context */
440 unsigned remoteid, localid;
443 * In SSH1, this value contains four bits:
445 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
446 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
447 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
448 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
450 * A channel is completely finished with when all four bits are set.
454 struct ssh1_data_channel {
457 struct ssh2_data_channel {
459 unsigned remwindow, remmaxpkt;
464 struct ssh_agent_channel {
465 unsigned char *message;
466 unsigned char msglen[4];
467 unsigned lensofar, totallen;
469 struct ssh_x11_channel {
472 struct ssh_pfd_channel {
479 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
480 * 2 use this structure in different ways, reflecting SSH 2's
481 * altogether saner approach to port forwarding.
483 * In SSH 1, you arrange a remote forwarding by sending the server
484 * the remote port number, and the local destination host:port.
485 * When a connection comes in, the server sends you back that
486 * host:port pair, and you connect to it. This is a ready-made
487 * security hole if you're not on the ball: a malicious server
488 * could send you back _any_ host:port pair, so if you trustingly
489 * connect to the address it gives you then you've just opened the
490 * entire inside of your corporate network just by connecting
491 * through it to a dodgy SSH server. Hence, we must store a list of
492 * host:port pairs we _are_ trying to forward to, and reject a
493 * connection request from the server if it's not in the list.
495 * In SSH 2, each side of the connection minds its own business and
496 * doesn't send unnecessary information to the other. You arrange a
497 * remote forwarding by sending the server just the remote port
498 * number. When a connection comes in, the server tells you which
499 * of its ports was connected to; and _you_ have to remember what
500 * local host:port pair went with that port number.
502 * Hence: in SSH 1 this structure stores host:port pairs we intend
503 * to allow connections to, and is indexed by those host:port
504 * pairs. In SSH 2 it stores a mapping from source port to
505 * destination host:port pair, and is indexed by source port.
507 struct ssh_rportfwd {
508 unsigned sport, dport;
515 unsigned long sequence;
522 * State associated with packet logging
526 struct logblank_t *blanks;
529 static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
530 struct Packet *pktin);
531 static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
532 struct Packet *pktin);
533 static void ssh1_protocol_setup(Ssh ssh);
534 static void ssh2_protocol_setup(Ssh ssh);
535 static void ssh_size(void *handle, int width, int height);
536 static void ssh_special(void *handle, Telnet_Special);
537 static int ssh2_try_send(struct ssh_channel *c);
538 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
539 static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
540 static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
541 static int ssh_sendbuffer(void *handle);
542 static void ssh_do_close(Ssh ssh);
543 static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
544 static int ssh2_pkt_getbool(struct Packet *pkt);
545 static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
547 struct rdpkt1_state_tag {
548 long len, pad, biglen, to_read;
549 unsigned long realcrc, gotcrc;
553 struct Packet *pktin;
556 struct rdpkt2_state_tag {
557 long len, pad, payload, packetlen, maclen;
560 unsigned long incoming_sequence;
561 struct Packet *pktin;
564 typedef void (*handler_fn_t)(Ssh ssh, struct Packet *pktin);
567 const struct plug_function_table *fn;
568 /* the above field _must_ be first in the structure */
570 SHA_State exhash, exhashbase;
577 unsigned char session_key[32];
579 int v1_remote_protoflags;
580 int v1_local_protoflags;
581 int agentfwd_enabled;
584 const struct ssh_cipher *cipher;
587 const struct ssh2_cipher *cscipher, *sccipher;
588 void *cs_cipher_ctx, *sc_cipher_ctx;
589 const struct ssh_mac *csmac, *scmac;
590 void *cs_mac_ctx, *sc_mac_ctx;
591 const struct ssh_compress *cscomp, *sccomp;
592 void *cs_comp_ctx, *sc_comp_ctx;
593 const struct ssh_kex *kex;
594 const struct ssh_signkey *hostkey;
595 unsigned char v2_session_id[20];
601 int echoing, editing;
605 int ospeed, ispeed; /* temporaries */
606 int term_width, term_height;
608 tree234 *channels; /* indexed by local id */
609 struct ssh_channel *mainchan; /* primary session channel */
616 SSH_STATE_BEFORE_SIZE,
622 int size_needed, eof_needed;
624 struct Packet **queue;
625 int queuelen, queuesize;
627 unsigned char *deferred_send_data;
628 int deferred_len, deferred_size;
631 * Gross hack: pscp will try to start SFTP but fall back to
632 * scp1 if that fails. This variable is the means by which
633 * scp.c can reach into the SSH code and find out which one it
639 * Used for username and password input.
641 char *userpass_input_buffer;
642 int userpass_input_buflen;
643 int userpass_input_bufpos;
644 int userpass_input_echo;
646 char *portfwd_strptr;
652 int v1_throttle_count;
655 int v1_stdout_throttling;
656 int v2_outgoing_sequence;
658 int ssh1_rdpkt_crstate;
659 int ssh2_rdpkt_crstate;
660 int do_ssh_init_crstate;
661 int ssh_gotdata_crstate;
662 int do_ssh1_login_crstate;
663 int do_ssh1_connection_crstate;
664 int do_ssh2_transport_crstate;
665 int do_ssh2_authconn_crstate;
667 void *do_ssh_init_state;
668 void *do_ssh1_login_state;
669 void *do_ssh2_transport_state;
670 void *do_ssh2_authconn_state;
672 struct rdpkt1_state_tag rdpkt1_state;
673 struct rdpkt2_state_tag rdpkt2_state;
675 /* ssh1 and ssh2 use this for different things, but both use it */
676 int protocol_initial_phase_done;
678 void (*protocol) (Ssh ssh, unsigned char *in, int inlen,
680 struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
683 * We maintain a full _copy_ of a Config structure here, not
684 * merely a pointer to it. That way, when we're passed a new
685 * one for reconfiguration, we can check the differences and
686 * potentially reconfigure port forwardings etc in mid-session.
691 * Used to transfer data back from async agent callbacks.
693 void *agent_response;
694 int agent_response_len;
697 * Dispatch table for packet types that we may have to deal
700 handler_fn_t packet_dispatch[256];
703 #define logevent(s) logevent(ssh->frontend, s)
705 /* logevent, only printf-formatted. */
706 static void logeventf(Ssh ssh, const char *fmt, ...)
712 buf = dupvprintf(fmt, ap);
718 #define bombout(msg) \
720 char *text = dupprintf msg; \
723 connection_fatal(ssh->frontend, "%s", text); \
727 /* Functions to leave bits out of the SSH packet log file. */
729 static void dont_log_password(Ssh ssh, struct Packet *pkt, int blanktype)
731 if (ssh->cfg.logomitpass)
732 pkt->logmode = blanktype;
735 static void dont_log_data(Ssh ssh, struct Packet *pkt, int blanktype)
737 if (ssh->cfg.logomitdata)
738 pkt->logmode = blanktype;
741 static void end_log_omission(Ssh ssh, struct Packet *pkt)
743 pkt->logmode = PKTLOG_EMIT;
746 static int ssh_channelcmp(void *av, void *bv)
748 struct ssh_channel *a = (struct ssh_channel *) av;
749 struct ssh_channel *b = (struct ssh_channel *) bv;
750 if (a->localid < b->localid)
752 if (a->localid > b->localid)
756 static int ssh_channelfind(void *av, void *bv)
758 unsigned *a = (unsigned *) av;
759 struct ssh_channel *b = (struct ssh_channel *) bv;
767 static int ssh_rportcmp_ssh1(void *av, void *bv)
769 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
770 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
772 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
773 return i < 0 ? -1 : +1;
774 if (a->dport > b->dport)
776 if (a->dport < b->dport)
781 static int ssh_rportcmp_ssh2(void *av, void *bv)
783 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
784 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
786 if (a->sport > b->sport)
788 if (a->sport < b->sport)
793 static int alloc_channel_id(Ssh ssh)
795 const unsigned CHANNEL_NUMBER_OFFSET = 256;
796 unsigned low, high, mid;
798 struct ssh_channel *c;
801 * First-fit allocation of channel numbers: always pick the
802 * lowest unused one. To do this, binary-search using the
803 * counted B-tree to find the largest channel ID which is in a
804 * contiguous sequence from the beginning. (Precisely
805 * everything in that sequence must have ID equal to its tree
806 * index plus CHANNEL_NUMBER_OFFSET.)
808 tsize = count234(ssh->channels);
812 while (high - low > 1) {
813 mid = (high + low) / 2;
814 c = index234(ssh->channels, mid);
815 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
816 low = mid; /* this one is fine */
818 high = mid; /* this one is past it */
821 * Now low points to either -1, or the tree index of the
822 * largest ID in the initial sequence.
825 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
826 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
828 return low + 1 + CHANNEL_NUMBER_OFFSET;
831 static void c_write(Ssh ssh, const char *buf, int len)
833 if ((flags & FLAG_STDERR)) {
835 for (i = 0; i < len; i++)
837 fputc(buf[i], stderr);
840 from_backend(ssh->frontend, 1, buf, len);
843 static void c_write_untrusted(Ssh ssh, const char *buf, int len)
846 for (i = 0; i < len; i++) {
848 c_write(ssh, "\r\n", 2);
849 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
850 c_write(ssh, buf + i, 1);
854 static void c_write_str(Ssh ssh, const char *buf)
856 c_write(ssh, buf, strlen(buf));
859 static void ssh_free_packet(struct Packet *pkt)
864 static struct Packet *ssh_new_packet(void)
866 struct Packet *pkt = snew(struct Packet);
870 pkt->logmode = PKTLOG_EMIT;
878 * Collect incoming data in the incoming packet buffer.
879 * Decipher and verify the packet when it is completely read.
880 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
881 * Update the *data and *datalen variables.
882 * Return a Packet structure when a packet is completed.
884 static struct Packet *ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
886 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
888 crBegin(ssh->ssh1_rdpkt_crstate);
890 st->pktin = ssh_new_packet();
893 st->pktin->length = 0;
895 for (st->i = st->len = 0; st->i < 4; st->i++) {
896 while ((*datalen) == 0)
898 st->len = (st->len << 8) + **data;
899 (*data)++, (*datalen)--;
902 st->pad = 8 - (st->len % 8);
903 st->biglen = st->len + st->pad;
904 st->pktin->length = st->len - 5;
906 if (st->biglen < 0) {
907 bombout(("Extremely large packet length from server suggests"
908 " data stream corruption"));
909 ssh_free_packet(st->pktin);
913 st->pktin->maxlen = st->biglen;
914 st->pktin->data = snewn(st->biglen + APIEXTRA, unsigned char);
916 st->to_read = st->biglen;
917 st->p = st->pktin->data;
918 while (st->to_read > 0) {
919 st->chunk = st->to_read;
920 while ((*datalen) == 0)
922 if (st->chunk > (*datalen))
923 st->chunk = (*datalen);
924 memcpy(st->p, *data, st->chunk);
926 *datalen -= st->chunk;
928 st->to_read -= st->chunk;
931 if (ssh->cipher && detect_attack(ssh->crcda_ctx, st->pktin->data,
933 bombout(("Network attack (CRC compensation) detected!"));
934 ssh_free_packet(st->pktin);
939 ssh->cipher->decrypt(ssh->v1_cipher_ctx, st->pktin->data, st->biglen);
941 st->realcrc = crc32_compute(st->pktin->data, st->biglen - 4);
942 st->gotcrc = GET_32BIT(st->pktin->data + st->biglen - 4);
943 if (st->gotcrc != st->realcrc) {
944 bombout(("Incorrect CRC received on packet"));
945 ssh_free_packet(st->pktin);
949 st->pktin->body = st->pktin->data + st->pad + 1;
950 st->pktin->savedpos = 0;
952 if (ssh->v1_compressing) {
953 unsigned char *decompblk;
955 if (!zlib_decompress_block(ssh->sc_comp_ctx,
956 st->pktin->body - 1, st->pktin->length + 1,
957 &decompblk, &decomplen)) {
958 bombout(("Zlib decompression encountered invalid data"));
959 ssh_free_packet(st->pktin);
963 if (st->pktin->maxlen < st->pad + decomplen) {
964 st->pktin->maxlen = st->pad + decomplen;
965 st->pktin->data = sresize(st->pktin->data,
966 st->pktin->maxlen + APIEXTRA,
968 st->pktin->body = st->pktin->data + st->pad + 1;
971 memcpy(st->pktin->body - 1, decompblk, decomplen);
973 st->pktin->length = decomplen - 1;
976 st->pktin->type = st->pktin->body[-1];
979 * Log incoming packet, possibly omitting sensitive fields.
983 struct logblank_t blank;
984 if (ssh->cfg.logomitdata) {
985 int do_blank = FALSE, blank_prefix = 0;
986 /* "Session data" packets - omit the data field */
987 if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
988 (st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
989 do_blank = TRUE; blank_prefix = 0;
990 } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
991 do_blank = TRUE; blank_prefix = 4;
994 blank.offset = blank_prefix;
995 blank.len = st->pktin->length;
996 blank.type = PKTLOG_OMIT;
1000 log_packet(ssh->logctx,
1001 PKT_INCOMING, st->pktin->type,
1002 ssh1_pkt_type(st->pktin->type),
1003 st->pktin->body, st->pktin->length,
1007 crFinish(st->pktin);
1010 static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
1012 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
1014 crBegin(ssh->ssh2_rdpkt_crstate);
1016 st->pktin = ssh_new_packet();
1018 st->pktin->type = 0;
1019 st->pktin->length = 0;
1021 st->cipherblk = ssh->sccipher->blksize;
1024 if (st->cipherblk < 8)
1027 st->pktin->data = snewn(st->cipherblk + APIEXTRA, unsigned char);
1030 * Acquire and decrypt the first block of the packet. This will
1031 * contain the length and padding details.
1033 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
1034 while ((*datalen) == 0)
1036 st->pktin->data[st->i] = *(*data)++;
1041 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1042 st->pktin->data, st->cipherblk);
1045 * Now get the length and padding figures.
1047 st->len = GET_32BIT(st->pktin->data);
1048 st->pad = st->pktin->data[4];
1051 * _Completely_ silly lengths should be stomped on before they
1052 * do us any more damage.
1054 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
1055 bombout(("Incoming packet was garbled on decryption"));
1056 ssh_free_packet(st->pktin);
1061 * This enables us to deduce the payload length.
1063 st->payload = st->len - st->pad - 1;
1065 st->pktin->length = st->payload + 5;
1068 * So now we can work out the total packet length.
1070 st->packetlen = st->len + 4;
1071 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
1074 * Allocate memory for the rest of the packet.
1076 st->pktin->maxlen = st->packetlen + st->maclen;
1077 st->pktin->data = sresize(st->pktin->data,
1078 st->pktin->maxlen + APIEXTRA,
1082 * Read and decrypt the remainder of the packet.
1084 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1086 while ((*datalen) == 0)
1088 st->pktin->data[st->i] = *(*data)++;
1091 /* Decrypt everything _except_ the MAC. */
1093 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1094 st->pktin->data + st->cipherblk,
1095 st->packetlen - st->cipherblk);
1101 && !ssh->scmac->verify(ssh->sc_mac_ctx, st->pktin->data, st->len + 4,
1102 st->incoming_sequence)) {
1103 bombout(("Incorrect MAC received on packet"));
1104 ssh_free_packet(st->pktin);
1108 st->pktin->sequence = st->incoming_sequence++;
1111 * Decompress packet payload.
1114 unsigned char *newpayload;
1117 ssh->sccomp->decompress(ssh->sc_comp_ctx,
1118 st->pktin->data + 5, st->pktin->length - 5,
1119 &newpayload, &newlen)) {
1120 if (st->pktin->maxlen < newlen + 5) {
1121 st->pktin->maxlen = newlen + 5;
1122 st->pktin->data = sresize(st->pktin->data,
1123 st->pktin->maxlen + APIEXTRA,
1126 st->pktin->length = 5 + newlen;
1127 memcpy(st->pktin->data + 5, newpayload, newlen);
1132 st->pktin->savedpos = 6;
1133 st->pktin->body = st->pktin->data;
1134 st->pktin->type = st->pktin->data[5];
1137 * Log incoming packet, possibly omitting sensitive fields.
1141 struct logblank_t blank;
1142 if (ssh->cfg.logomitdata) {
1143 int do_blank = FALSE, blank_prefix = 0;
1144 /* "Session data" packets - omit the data field */
1145 if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
1146 do_blank = TRUE; blank_prefix = 4;
1147 } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
1148 do_blank = TRUE; blank_prefix = 8;
1151 blank.offset = blank_prefix;
1152 blank.len = (st->pktin->length-6) - blank_prefix;
1153 blank.type = PKTLOG_OMIT;
1157 log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
1158 ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
1159 st->pktin->data+6, st->pktin->length-6,
1163 crFinish(st->pktin);
1166 static void ssh1_pktout_size(struct Packet *pkt, int len)
1170 len += 5; /* type and CRC */
1171 pad = 8 - (len % 8);
1174 pkt->length = len - 5;
1175 if (pkt->maxlen < biglen) {
1176 pkt->maxlen = biglen;
1177 pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
1179 pkt->body = pkt->data + 4 + pad + 1;
1182 static struct Packet *s_wrpkt_start(int type, int len)
1184 struct Packet *pkt = ssh_new_packet();
1185 ssh1_pktout_size(pkt, len);
1187 /* Initialise log omission state */
1193 static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
1199 * XXX various versions of SC (including 8.8.4) screw up the
1200 * register allocation in this function and use the same register
1201 * (D6) for len and as a temporary, with predictable results. The
1202 * following sledgehammer prevents this.
1208 pkt->body[-1] = pkt->type;
1211 log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
1212 ssh1_pkt_type(pkt->type),
1213 pkt->body, pkt->length,
1214 pkt->nblanks, pkt->blanks);
1215 sfree(pkt->blanks); pkt->blanks = NULL;
1218 if (ssh->v1_compressing) {
1219 unsigned char *compblk;
1221 zlib_compress_block(ssh->cs_comp_ctx,
1222 pkt->body - 1, pkt->length + 1,
1223 &compblk, &complen);
1224 ssh1_pktout_size(pkt, complen - 1);
1225 memcpy(pkt->body - 1, compblk, complen);
1229 len = pkt->length + 5; /* type and CRC */
1230 pad = 8 - (len % 8);
1233 for (i = 0; i < pad; i++)
1234 pkt->data[i + 4] = random_byte();
1235 crc = crc32_compute(pkt->data + 4, biglen - 4);
1236 PUT_32BIT(pkt->data + biglen, crc);
1237 PUT_32BIT(pkt->data, len);
1240 ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
1245 static void s_wrpkt(Ssh ssh, struct Packet *pkt)
1248 len = s_wrpkt_prepare(ssh, pkt);
1249 backlog = sk_write(ssh->s, (char *)pkt->data, len);
1250 if (backlog > SSH_MAX_BACKLOG)
1251 ssh_throttle_all(ssh, 1, backlog);
1254 static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
1257 len = s_wrpkt_prepare(ssh, pkt);
1258 if (ssh->deferred_len + len > ssh->deferred_size) {
1259 ssh->deferred_size = ssh->deferred_len + len + 128;
1260 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1264 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
1265 ssh->deferred_len += len;
1269 * Construct a packet with the specified contents.
1271 static struct Packet *construct_packet(Ssh ssh, int pkttype,
1272 va_list ap1, va_list ap2)
1274 unsigned char *p, *argp, argchar;
1275 unsigned long argint;
1276 int pktlen, argtype, arglen;
1281 while ((argtype = va_arg(ap1, int)) != PKT_END) {
1284 (void) va_arg(ap1, int);
1288 (void) va_arg(ap1, int);
1292 (void) va_arg(ap1, unsigned char *);
1293 arglen = va_arg(ap1, int);
1297 argp = va_arg(ap1, unsigned char *);
1298 arglen = strlen((char *)argp);
1299 pktlen += 4 + arglen;
1302 bn = va_arg(ap1, Bignum);
1303 pktlen += ssh1_bignum_length(bn);
1308 /* ignore this pass */
1315 pkt = s_wrpkt_start(pkttype, pktlen);
1318 while ((argtype = va_arg(ap2, int)) != PKT_END) {
1319 int offset = p - pkt->body, len = 0;
1321 /* Actual fields in the packet */
1323 argint = va_arg(ap2, int);
1324 PUT_32BIT(p, argint);
1328 argchar = (unsigned char) va_arg(ap2, int);
1333 argp = va_arg(ap2, unsigned char *);
1334 arglen = va_arg(ap2, int);
1335 memcpy(p, argp, arglen);
1339 argp = va_arg(ap2, unsigned char *);
1340 arglen = strlen((char *)argp);
1341 PUT_32BIT(p, arglen);
1342 memcpy(p + 4, argp, arglen);
1346 bn = va_arg(ap2, Bignum);
1347 len = ssh1_write_bignum(p, bn);
1349 /* Tokens for modifications to packet logging */
1351 dont_log_password(ssh, pkt, PKTLOG_BLANK);
1354 dont_log_data(ssh, pkt, PKTLOG_OMIT);
1357 end_log_omission(ssh, pkt);
1361 /* Deal with logfile omission, if required. */
1362 if (len && (pkt->logmode != PKTLOG_EMIT)) {
1364 pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
1366 pkt->blanks[pkt->nblanks-1].offset = offset;
1367 pkt->blanks[pkt->nblanks-1].len = len;
1368 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1375 static void send_packet(Ssh ssh, int pkttype, ...)
1379 va_start(ap1, pkttype);
1380 va_start(ap2, pkttype);
1381 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1385 ssh_free_packet(pkt);
1388 static void defer_packet(Ssh ssh, int pkttype, ...)
1392 va_start(ap1, pkttype);
1393 va_start(ap2, pkttype);
1394 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1397 s_wrpkt_defer(ssh, pkt);
1398 ssh_free_packet(pkt);
1401 static int ssh_versioncmp(char *a, char *b)
1404 unsigned long av, bv;
1406 av = strtoul(a, &ae, 10);
1407 bv = strtoul(b, &be, 10);
1409 return (av < bv ? -1 : +1);
1414 av = strtoul(ae, &ae, 10);
1415 bv = strtoul(be, &be, 10);
1417 return (av < bv ? -1 : +1);
1422 * Utility routines for putting an SSH-protocol `string' and
1423 * `uint32' into a SHA state.
1426 static void sha_string(SHA_State * s, void *str, int len)
1428 unsigned char lenblk[4];
1429 PUT_32BIT(lenblk, len);
1430 SHA_Bytes(s, lenblk, 4);
1431 SHA_Bytes(s, str, len);
1434 static void sha_uint32(SHA_State * s, unsigned i)
1436 unsigned char intblk[4];
1437 PUT_32BIT(intblk, i);
1438 SHA_Bytes(s, intblk, 4);
1442 * SSH2 packet construction functions.
1444 static void ssh2_pkt_ensure(struct Packet *pkt, int length)
1446 if (pkt->maxlen < length) {
1447 pkt->maxlen = length + 256;
1448 pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
1451 static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
1453 if (pkt->logmode != PKTLOG_EMIT) {
1455 pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
1456 pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
1457 pkt->blanks[pkt->nblanks-1].len = len;
1458 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1461 ssh2_pkt_ensure(pkt, pkt->length);
1462 memcpy(pkt->data + pkt->length - len, data, len);
1464 static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
1466 ssh2_pkt_adddata(pkt, &byte, 1);
1468 static struct Packet *ssh2_pkt_init(int pkt_type)
1470 struct Packet *pkt = ssh_new_packet();
1472 ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
1475 static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
1477 ssh2_pkt_adddata(pkt, &value, 1);
1479 static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
1482 PUT_32BIT(x, value);
1483 ssh2_pkt_adddata(pkt, x, 4);
1485 static void ssh2_pkt_addstring_start(struct Packet *pkt)
1487 ssh2_pkt_adduint32(pkt, 0);
1488 pkt->savedpos = pkt->length;
1490 static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
1492 ssh2_pkt_adddata(pkt, data, strlen(data));
1493 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
1495 static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
1497 ssh2_pkt_adddata(pkt, data, len);
1498 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
1500 static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
1502 ssh2_pkt_addstring_start(pkt);
1503 ssh2_pkt_addstring_str(pkt, data);
1505 static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
1508 int i, n = (bignum_bitcount(b) + 7) / 8;
1509 p = snewn(n + 1, unsigned char);
1511 fatalbox("out of memory");
1513 for (i = 1; i <= n; i++)
1514 p[i] = bignum_byte(b, n - i);
1516 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1518 memmove(p, p + i, n + 1 - i);
1522 static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
1526 p = ssh2_mpint_fmt(b, &len);
1527 ssh2_pkt_addstring_start(pkt);
1528 ssh2_pkt_addstring_data(pkt, (char *)p, len);
1533 * Construct an SSH2 final-form packet: compress it, encrypt it,
1534 * put the MAC on it. Final packet, ready to be sent, is stored in
1535 * pkt->data. Total length is returned.
1537 static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
1539 int cipherblk, maclen, padding, i;
1542 log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
1543 ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
1544 pkt->data + 6, pkt->length - 6,
1545 pkt->nblanks, pkt->blanks);
1546 sfree(pkt->blanks); pkt->blanks = NULL;
1550 * Compress packet payload.
1553 unsigned char *newpayload;
1556 ssh->cscomp->compress(ssh->cs_comp_ctx, pkt->data + 5,
1558 &newpayload, &newlen)) {
1560 ssh2_pkt_adddata(pkt, newpayload, newlen);
1566 * Add padding. At least four bytes, and must also bring total
1567 * length (minus MAC) up to a multiple of the block size.
1569 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
1570 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
1573 (cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
1574 maclen = ssh->csmac ? ssh->csmac->len : 0;
1575 ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
1576 pkt->data[4] = padding;
1577 for (i = 0; i < padding; i++)
1578 pkt->data[pkt->length + i] = random_byte();
1579 PUT_32BIT(pkt->data, pkt->length + padding - 4);
1581 ssh->csmac->generate(ssh->cs_mac_ctx, pkt->data,
1582 pkt->length + padding,
1583 ssh->v2_outgoing_sequence);
1584 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1587 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
1588 pkt->data, pkt->length + padding);
1590 /* Ready-to-send packet starts at pkt->data. We return length. */
1591 return pkt->length + padding + maclen;
1595 * Routines called from the main SSH code to send packets. There
1596 * are quite a few of these, because we have two separate
1597 * mechanisms for delaying the sending of packets:
1599 * - In order to send an IGNORE message and a password message in
1600 * a single fixed-length blob, we require the ability to
1601 * concatenate the encrypted forms of those two packets _into_ a
1602 * single blob and then pass it to our <network.h> transport
1603 * layer in one go. Hence, there's a deferment mechanism which
1604 * works after packet encryption.
1606 * - In order to avoid sending any connection-layer messages
1607 * during repeat key exchange, we have to queue up any such
1608 * outgoing messages _before_ they are encrypted (and in
1609 * particular before they're allocated sequence numbers), and
1610 * then send them once we've finished.
1612 * I call these mechanisms `defer' and `queue' respectively, so as
1613 * to distinguish them reasonably easily.
1615 * The functions send_noqueue() and defer_noqueue() free the packet
1616 * structure they are passed. Every outgoing packet goes through
1617 * precisely one of these functions in its life; packets passed to
1618 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1619 * these or get queued, and then when the queue is later emptied
1620 * the packets are all passed to defer_noqueue().
1624 * Send an SSH2 packet immediately, without queuing or deferring.
1626 static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
1630 len = ssh2_pkt_construct(ssh, pkt);
1631 backlog = sk_write(ssh->s, (char *)pkt->data, len);
1632 if (backlog > SSH_MAX_BACKLOG)
1633 ssh_throttle_all(ssh, 1, backlog);
1634 ssh_free_packet(pkt);
1638 * Defer an SSH2 packet.
1640 static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
1642 int len = ssh2_pkt_construct(ssh, pkt);
1643 if (ssh->deferred_len + len > ssh->deferred_size) {
1644 ssh->deferred_size = ssh->deferred_len + len + 128;
1645 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1649 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
1650 ssh->deferred_len += len;
1651 ssh_free_packet(pkt);
1655 * Queue an SSH2 packet.
1657 static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
1659 assert(ssh->queueing);
1661 if (ssh->queuelen >= ssh->queuesize) {
1662 ssh->queuesize = ssh->queuelen + 32;
1663 ssh->queue = sresize(ssh->queue, ssh->queuesize, struct Packet *);
1666 ssh->queue[ssh->queuelen++] = pkt;
1670 * Either queue or send a packet, depending on whether queueing is
1673 static void ssh2_pkt_send(Ssh ssh, struct Packet *pkt)
1676 ssh2_pkt_queue(ssh, pkt);
1678 ssh2_pkt_send_noqueue(ssh, pkt);
1682 * Either queue or defer a packet, depending on whether queueing is
1685 static void ssh2_pkt_defer(Ssh ssh, struct Packet *pkt)
1688 ssh2_pkt_queue(ssh, pkt);
1690 ssh2_pkt_defer_noqueue(ssh, pkt);
1694 * Send the whole deferred data block constructed by
1695 * ssh2_pkt_defer() or SSH1's defer_packet().
1697 * The expected use of the defer mechanism is that you call
1698 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1699 * not currently queueing, this simply sets up deferred_send_data
1700 * and then sends it. If we _are_ currently queueing, the calls to
1701 * ssh2_pkt_defer() put the deferred packets on to the queue
1702 * instead, and therefore ssh_pkt_defersend() has no deferred data
1703 * to send. Hence, there's no need to make it conditional on
1706 static void ssh_pkt_defersend(Ssh ssh)
1709 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1711 ssh->deferred_len = ssh->deferred_size = 0;
1712 sfree(ssh->deferred_send_data);
1713 ssh->deferred_send_data = NULL;
1714 if (backlog > SSH_MAX_BACKLOG)
1715 ssh_throttle_all(ssh, 1, backlog);
1719 * Send all queued SSH2 packets. We send them by means of
1720 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1721 * packets that needed to be lumped together.
1723 static void ssh2_pkt_queuesend(Ssh ssh)
1727 assert(!ssh->queueing);
1729 for (i = 0; i < ssh->queuelen; i++)
1730 ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
1733 ssh_pkt_defersend(ssh);
1737 void bndebug(char *string, Bignum b)
1741 p = ssh2_mpint_fmt(b, &len);
1742 debug(("%s", string));
1743 for (i = 0; i < len; i++)
1744 debug((" %02x", p[i]));
1750 static void sha_mpint(SHA_State * s, Bignum b)
1754 p = ssh2_mpint_fmt(b, &len);
1755 sha_string(s, p, len);
1760 * Packet decode functions for both SSH1 and SSH2.
1762 static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
1764 unsigned long value;
1765 if (pkt->length - pkt->savedpos < 4)
1766 return 0; /* arrgh, no way to decline (FIXME?) */
1767 value = GET_32BIT(pkt->body + pkt->savedpos);
1771 static int ssh2_pkt_getbool(struct Packet *pkt)
1773 unsigned long value;
1774 if (pkt->length - pkt->savedpos < 1)
1775 return 0; /* arrgh, no way to decline (FIXME?) */
1776 value = pkt->body[pkt->savedpos] != 0;
1780 static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length)
1785 if (pkt->length - pkt->savedpos < 4)
1787 len = GET_32BIT(pkt->body + pkt->savedpos);
1792 if (pkt->length - pkt->savedpos < *length)
1794 *p = (char *)(pkt->body + pkt->savedpos);
1795 pkt->savedpos += *length;
1797 static void *ssh_pkt_getdata(struct Packet *pkt, int length)
1799 if (pkt->length - pkt->savedpos < length)
1801 pkt->savedpos += length;
1802 return pkt->body + (pkt->savedpos - length);
1804 static int ssh1_pkt_getrsakey(struct Packet *pkt, struct RSAKey *key,
1805 unsigned char **keystr)
1809 j = makekey(pkt->body + pkt->savedpos,
1810 pkt->length - pkt->savedpos,
1817 assert(pkt->savedpos < pkt->length);
1821 static Bignum ssh1_pkt_getmp(struct Packet *pkt)
1826 j = ssh1_read_bignum(pkt->body + pkt->savedpos,
1827 pkt->length - pkt->savedpos, &b);
1835 static Bignum ssh2_pkt_getmp(struct Packet *pkt)
1841 ssh_pkt_getstring(pkt, &p, &length);
1846 b = bignum_from_bytes((unsigned char *)p, length);
1851 * Helper function to add an SSH2 signature blob to a packet.
1852 * Expects to be shown the public key blob as well as the signature
1853 * blob. Normally works just like ssh2_pkt_addstring, but will
1854 * fiddle with the signature packet if necessary for
1855 * BUG_SSH2_RSA_PADDING.
1857 static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt,
1858 void *pkblob_v, int pkblob_len,
1859 void *sigblob_v, int sigblob_len)
1861 unsigned char *pkblob = (unsigned char *)pkblob_v;
1862 unsigned char *sigblob = (unsigned char *)sigblob_v;
1864 /* dmemdump(pkblob, pkblob_len); */
1865 /* dmemdump(sigblob, sigblob_len); */
1868 * See if this is in fact an ssh-rsa signature and a buggy
1869 * server; otherwise we can just do this the easy way.
1871 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1872 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1873 int pos, len, siglen;
1876 * Find the byte length of the modulus.
1879 pos = 4+7; /* skip over "ssh-rsa" */
1880 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
1881 len = GET_32BIT(pkblob+pos); /* find length of modulus */
1882 pos += 4; /* find modulus itself */
1883 while (len > 0 && pkblob[pos] == 0)
1885 /* debug(("modulus length is %d\n", len)); */
1888 * Now find the signature integer.
1890 pos = 4+7; /* skip over "ssh-rsa" */
1891 siglen = GET_32BIT(sigblob+pos);
1892 /* debug(("signature length is %d\n", siglen)); */
1894 if (len != siglen) {
1895 unsigned char newlen[4];
1896 ssh2_pkt_addstring_start(pkt);
1897 ssh2_pkt_addstring_data(pkt, (char *)sigblob, pos);
1898 /* dmemdump(sigblob, pos); */
1899 pos += 4; /* point to start of actual sig */
1900 PUT_32BIT(newlen, len);
1901 ssh2_pkt_addstring_data(pkt, (char *)newlen, 4);
1902 /* dmemdump(newlen, 4); */
1904 while (len-- > siglen) {
1905 ssh2_pkt_addstring_data(pkt, (char *)newlen, 1);
1906 /* dmemdump(newlen, 1); */
1908 ssh2_pkt_addstring_data(pkt, (char *)(sigblob+pos), siglen);
1909 /* dmemdump(sigblob+pos, siglen); */
1913 /* Otherwise fall through and do it the easy way. */
1916 ssh2_pkt_addstring_start(pkt);
1917 ssh2_pkt_addstring_data(pkt, (char *)sigblob, sigblob_len);
1921 * Examine the remote side's version string and compare it against
1922 * a list of known buggy implementations.
1924 static void ssh_detect_bugs(Ssh ssh, char *vstring)
1926 char *imp; /* pointer to implementation part */
1928 imp += strcspn(imp, "-");
1930 imp += strcspn(imp, "-");
1933 ssh->remote_bugs = 0;
1935 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
1936 (ssh->cfg.sshbug_ignore1 == AUTO &&
1937 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
1938 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
1939 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
1940 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
1942 * These versions don't support SSH1_MSG_IGNORE, so we have
1943 * to use a different defence against password length
1946 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
1947 logevent("We believe remote version has SSH1 ignore bug");
1950 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
1951 (ssh->cfg.sshbug_plainpw1 == AUTO &&
1952 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
1954 * These versions need a plain password sent; they can't
1955 * handle having a null and a random length of data after
1958 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
1959 logevent("We believe remote version needs a plain SSH1 password");
1962 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
1963 (ssh->cfg.sshbug_rsa1 == AUTO &&
1964 (!strcmp(imp, "Cisco-1.25")))) {
1966 * These versions apparently have no clue whatever about
1967 * RSA authentication and will panic and die if they see
1968 * an AUTH_RSA message.
1970 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
1971 logevent("We believe remote version can't handle RSA authentication");
1974 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
1975 (ssh->cfg.sshbug_hmac2 == AUTO &&
1976 !wc_match("* VShell", imp) &&
1977 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
1978 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
1979 wc_match("2.1 *", imp)))) {
1981 * These versions have the HMAC bug.
1983 ssh->remote_bugs |= BUG_SSH2_HMAC;
1984 logevent("We believe remote version has SSH2 HMAC bug");
1987 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
1988 (ssh->cfg.sshbug_derivekey2 == AUTO &&
1989 !wc_match("* VShell", imp) &&
1990 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
1992 * These versions have the key-derivation bug (failing to
1993 * include the literal shared secret in the hashes that
1994 * generate the keys).
1996 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
1997 logevent("We believe remote version has SSH2 key-derivation bug");
2000 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
2001 (ssh->cfg.sshbug_rsapad2 == AUTO &&
2002 (wc_match("OpenSSH_2.[5-9]*", imp) ||
2003 wc_match("OpenSSH_3.[0-2]*", imp)))) {
2005 * These versions have the SSH2 RSA padding bug.
2007 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
2008 logevent("We believe remote version has SSH2 RSA padding bug");
2011 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
2012 (ssh->cfg.sshbug_pksessid2 == AUTO &&
2013 wc_match("OpenSSH_2.[0-2]*", imp))) {
2015 * These versions have the SSH2 session-ID bug in
2016 * public-key authentication.
2018 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
2019 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2022 if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
2024 * User specified the SSH2 DH GEX bug.
2026 ssh->remote_bugs |= BUG_SSH2_DH_GEX;
2027 logevent("We believe remote version has SSH2 DH group exchange bug");
2031 static int do_ssh_init(Ssh ssh, unsigned char c)
2033 struct do_ssh_init_state {
2041 crState(do_ssh_init_state);
2043 crBegin(ssh->do_ssh_init_crstate);
2045 /* Search for the string "SSH-" in the input. */
2048 static const int transS[] = { 1, 2, 2, 1 };
2049 static const int transH[] = { 0, 0, 3, 0 };
2050 static const int transminus[] = { 0, 0, 0, -1 };
2052 s->i = transS[s->i];
2054 s->i = transH[s->i];
2056 s->i = transminus[s->i];
2061 crReturn(1); /* get another character */
2065 s->vstring = snewn(s->vstrsize, char);
2066 strcpy(s->vstring, "SSH-");
2070 crReturn(1); /* get another char */
2071 if (s->vslen >= s->vstrsize - 1) {
2073 s->vstring = sresize(s->vstring, s->vstrsize, char);
2075 s->vstring[s->vslen++] = c;
2078 s->version[s->i] = '\0';
2080 } else if (s->i < sizeof(s->version) - 1)
2081 s->version[s->i++] = c;
2082 } else if (c == '\012')
2086 ssh->agentfwd_enabled = FALSE;
2087 ssh->rdpkt2_state.incoming_sequence = 0;
2089 s->vstring[s->vslen] = 0;
2090 s->vstring[strcspn(s->vstring, "\r\n")] = '\0';/* remove EOL chars */
2093 vlog = snewn(20 + s->vslen, char);
2094 sprintf(vlog, "Server version: %s", s->vstring);
2098 ssh_detect_bugs(ssh, s->vstring);
2101 * Decide which SSH protocol version to support.
2104 /* Anything strictly below "2.0" means protocol 1 is supported. */
2105 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
2106 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2107 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
2109 if (ssh->cfg.sshprot == 0 && !s->proto1) {
2110 bombout(("SSH protocol version 1 required by user but not provided by server"));
2113 if (ssh->cfg.sshprot == 3 && !s->proto2) {
2114 bombout(("SSH protocol version 2 required by user but not provided by server"));
2118 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
2122 char verstring[80], vlog[100];
2123 sprintf(verstring, "SSH-2.0-%s", sshver);
2124 SHA_Init(&ssh->exhashbase);
2126 * Hash our version string and their version string.
2128 sha_string(&ssh->exhashbase, verstring, strlen(verstring));
2129 sha_string(&ssh->exhashbase, s->vstring, strcspn(s->vstring, "\r\n"));
2130 sprintf(vlog, "We claim version: %s", verstring);
2132 strcat(verstring, "\012");
2133 logevent("Using SSH protocol version 2");
2134 sk_write(ssh->s, verstring, strlen(verstring));
2135 ssh->protocol = ssh2_protocol;
2136 ssh2_protocol_setup(ssh);
2138 ssh->s_rdpkt = ssh2_rdpkt;
2143 char verstring[80], vlog[100];
2144 sprintf(verstring, "SSH-%s-%s",
2145 (ssh_versioncmp(s->version, "1.5") <= 0 ? s->version : "1.5"),
2147 sprintf(vlog, "We claim version: %s", verstring);
2149 strcat(verstring, "\012");
2151 logevent("Using SSH protocol version 1");
2152 sk_write(ssh->s, verstring, strlen(verstring));
2153 ssh->protocol = ssh1_protocol;
2154 ssh1_protocol_setup(ssh);
2156 ssh->s_rdpkt = ssh1_rdpkt;
2158 update_specials_menu(ssh->frontend);
2159 ssh->state = SSH_STATE_BEFORE_SIZE;
2166 static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
2168 crBegin(ssh->ssh_gotdata_crstate);
2171 * To begin with, feed the characters one by one to the
2172 * protocol initialisation / selection function do_ssh_init().
2173 * When that returns 0, we're done with the initial greeting
2174 * exchange and can move on to packet discipline.
2177 int ret; /* need not be kept across crReturn */
2179 crReturnV; /* more data please */
2180 ret = do_ssh_init(ssh, *data);
2188 * We emerge from that loop when the initial negotiation is
2189 * over and we have selected an s_rdpkt function. Now pass
2190 * everything to s_rdpkt, and then pass the resulting packets
2191 * to the proper protocol handler.
2196 while (datalen > 0) {
2197 struct Packet *pktin = ssh->s_rdpkt(ssh, &data, &datalen);
2199 ssh->protocol(ssh, NULL, 0, pktin);
2200 ssh_free_packet(pktin);
2202 if (ssh->state == SSH_STATE_CLOSED)
2210 static void ssh_do_close(Ssh ssh)
2213 struct ssh_channel *c;
2215 ssh->state = SSH_STATE_CLOSED;
2221 * Now we must shut down any port and X forwardings going
2222 * through this connection.
2224 if (ssh->channels) {
2225 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2228 x11_close(c->u.x11.s);
2231 pfd_close(c->u.pfd.s);
2234 del234(ssh->channels, c);
2235 if (ssh->version == 2)
2236 bufchain_clear(&c->v.v2.outbuffer);
2242 static int ssh_closing(Plug plug, const char *error_msg, int error_code,
2245 Ssh ssh = (Ssh) plug;
2248 /* A socket error has occurred. */
2249 logevent(error_msg);
2250 connection_fatal(ssh->frontend, "%s", error_msg);
2252 /* Otherwise, the remote side closed the connection normally. */
2257 static int ssh_receive(Plug plug, int urgent, char *data, int len)
2259 Ssh ssh = (Ssh) plug;
2260 ssh_gotdata(ssh, (unsigned char *)data, len);
2261 if (ssh->state == SSH_STATE_CLOSED) {
2268 static void ssh_sent(Plug plug, int bufsize)
2270 Ssh ssh = (Ssh) plug;
2272 * If the send backlog on the SSH socket itself clears, we
2273 * should unthrottle the whole world if it was throttled.
2275 if (bufsize < SSH_MAX_BACKLOG)
2276 ssh_throttle_all(ssh, 0, bufsize);
2280 * Connect to specified host and port.
2281 * Returns an error message, or NULL on success.
2282 * Also places the canonical host name into `realhost'. It must be
2283 * freed by the caller.
2285 static const char *connect_to_host(Ssh ssh, char *host, int port,
2286 char **realhost, int nodelay, int keepalive)
2288 static const struct plug_function_table fn_table = {
2298 ssh->savedhost = snewn(1 + strlen(host), char);
2299 if (!ssh->savedhost)
2300 fatalbox("Out of memory");
2301 strcpy(ssh->savedhost, host);
2304 port = 22; /* default ssh port */
2305 ssh->savedport = port;
2310 logeventf(ssh, "Looking up host \"%s\"", host);
2311 addr = name_lookup(host, port, realhost, &ssh->cfg);
2312 if ((err = sk_addr_error(addr)) != NULL) {
2322 sk_getaddr(addr, addrbuf, 100);
2323 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
2325 ssh->fn = &fn_table;
2326 ssh->s = new_connection(addr, *realhost, port,
2327 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
2328 if ((err = sk_socket_error(ssh->s)) != NULL) {
2337 * Throttle or unthrottle the SSH connection.
2339 static void ssh1_throttle(Ssh ssh, int adjust)
2341 int old_count = ssh->v1_throttle_count;
2342 ssh->v1_throttle_count += adjust;
2343 assert(ssh->v1_throttle_count >= 0);
2344 if (ssh->v1_throttle_count && !old_count) {
2345 sk_set_frozen(ssh->s, 1);
2346 } else if (!ssh->v1_throttle_count && old_count) {
2347 sk_set_frozen(ssh->s, 0);
2352 * Throttle or unthrottle _all_ local data streams (for when sends
2353 * on the SSH connection itself back up).
2355 static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
2358 struct ssh_channel *c;
2360 if (enable == ssh->throttled_all)
2362 ssh->throttled_all = enable;
2363 ssh->overall_bufsize = bufsize;
2366 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2368 case CHAN_MAINSESSION:
2370 * This is treated separately, outside the switch.
2374 x11_override_throttle(c->u.x11.s, enable);
2377 /* Agent channels require no buffer management. */
2380 pfd_override_throttle(c->u.pfd.s, enable);
2387 * Username and password input, abstracted off into routines
2388 * reusable in several places - even between SSH1 and SSH2.
2391 /* Set up a username or password input loop on a given buffer. */
2392 static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
2394 ssh->userpass_input_buffer = buffer;
2395 ssh->userpass_input_buflen = buflen;
2396 ssh->userpass_input_bufpos = 0;
2397 ssh->userpass_input_echo = echo;
2401 * Process some terminal data in the course of username/password
2402 * input. Returns >0 for success (line of input returned in
2403 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2404 * for inconclusive (keep waiting for more input please).
2406 static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
2411 switch (c = *in++) {
2414 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2415 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
2420 if (ssh->userpass_input_bufpos > 0) {
2421 if (ssh->userpass_input_echo)
2422 c_write_str(ssh, "\b \b");
2423 ssh->userpass_input_bufpos--;
2428 while (ssh->userpass_input_bufpos > 0) {
2429 if (ssh->userpass_input_echo)
2430 c_write_str(ssh, "\b \b");
2431 ssh->userpass_input_bufpos--;
2440 * This simplistic check for printability is disabled
2441 * when we're doing password input, because some people
2442 * have control characters in their passwords.o
2444 if ((!ssh->userpass_input_echo ||
2445 (c >= ' ' && c <= '~') ||
2446 ((unsigned char) c >= 160))
2447 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2448 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2449 if (ssh->userpass_input_echo)
2450 c_write(ssh, &c, 1);
2458 static void ssh_agent_callback(void *sshv, void *reply, int replylen)
2460 Ssh ssh = (Ssh) sshv;
2462 ssh->agent_response = reply;
2463 ssh->agent_response_len = replylen;
2465 if (ssh->version == 1)
2466 do_ssh1_login(ssh, NULL, -1, NULL);
2468 do_ssh2_authconn(ssh, NULL, -1, NULL);
2471 static void ssh_agentf_callback(void *cv, void *reply, int replylen)
2473 struct ssh_channel *c = (struct ssh_channel *)cv;
2475 void *sentreply = reply;
2478 /* Fake SSH_AGENT_FAILURE. */
2479 sentreply = "\0\0\0\1\5";
2482 if (ssh->version == 2) {
2483 ssh2_add_channel_data(c, sentreply, replylen);
2486 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2487 PKT_INT, c->remoteid,
2490 PKT_DATA, sentreply, replylen,
2499 * Handle the key exchange and user authentication phases.
2501 static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
2502 struct Packet *pktin)
2505 unsigned char cookie[8], *ptr;
2506 struct RSAKey servkey, hostkey;
2507 struct MD5Context md5c;
2508 struct do_ssh1_login_state {
2510 unsigned char *rsabuf, *keystr1, *keystr2;
2511 unsigned long supported_ciphers_mask, supported_auths_mask;
2512 int tried_publickey, tried_agent;
2513 int tis_auth_refused, ccard_auth_refused;
2514 unsigned char session_id[16];
2517 void *publickey_blob;
2518 int publickey_bloblen;
2524 unsigned char request[5], *response, *p;
2533 crState(do_ssh1_login_state);
2535 crBegin(ssh->do_ssh1_login_crstate);
2542 if (pktin->type != SSH1_SMSG_PUBLIC_KEY) {
2543 bombout(("Public key packet not received"));
2547 logevent("Received public keys");
2549 ptr = ssh_pkt_getdata(pktin, 8);
2551 bombout(("SSH1 public key packet stopped before random cookie"));
2554 memcpy(cookie, ptr, 8);
2556 if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
2557 !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
2558 bombout(("Failed to read SSH1 public keys from public key packet"));
2563 * Log the host key fingerprint.
2567 logevent("Host key fingerprint is:");
2568 strcpy(logmsg, " ");
2569 hostkey.comment = NULL;
2570 rsa_fingerprint(logmsg + strlen(logmsg),
2571 sizeof(logmsg) - strlen(logmsg), &hostkey);
2575 ssh->v1_remote_protoflags = ssh_pkt_getuint32(pktin);
2576 s->supported_ciphers_mask = ssh_pkt_getuint32(pktin);
2577 s->supported_auths_mask = ssh_pkt_getuint32(pktin);
2579 ssh->v1_local_protoflags =
2580 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2581 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
2584 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2585 MD5Update(&md5c, s->keystr1, servkey.bytes);
2586 MD5Update(&md5c, cookie, 8);
2587 MD5Final(s->session_id, &md5c);
2589 for (i = 0; i < 32; i++)
2590 ssh->session_key[i] = random_byte();
2593 * Verify that the `bits' and `bytes' parameters match.
2595 if (hostkey.bits > hostkey.bytes * 8 ||
2596 servkey.bits > servkey.bytes * 8) {
2597 bombout(("SSH1 public keys were badly formatted"));
2601 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
2603 s->rsabuf = snewn(s->len, unsigned char);
2605 fatalbox("Out of memory");
2608 * Verify the host key.
2612 * First format the key into a string.
2614 int len = rsastr_len(&hostkey);
2615 char fingerprint[100];
2616 char *keystr = snewn(len, char);
2618 fatalbox("Out of memory");
2619 rsastr_fmt(keystr, &hostkey);
2620 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
2621 verify_ssh_host_key(ssh->frontend,
2622 ssh->savedhost, ssh->savedport, "rsa", keystr,
2627 for (i = 0; i < 32; i++) {
2628 s->rsabuf[i] = ssh->session_key[i];
2630 s->rsabuf[i] ^= s->session_id[i];
2633 if (hostkey.bytes > servkey.bytes) {
2634 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2636 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
2638 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2640 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2643 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2647 logevent("Encrypted session key");
2650 int cipher_chosen = 0, warn = 0;
2651 char *cipher_string = NULL;
2653 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
2654 int next_cipher = ssh->cfg.ssh_cipherlist[i];
2655 if (next_cipher == CIPHER_WARN) {
2656 /* If/when we choose a cipher, warn about it */
2658 } else if (next_cipher == CIPHER_AES) {
2659 /* XXX Probably don't need to mention this. */
2660 logevent("AES not supported in SSH1, skipping");
2662 switch (next_cipher) {
2663 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
2664 cipher_string = "3DES"; break;
2665 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
2666 cipher_string = "Blowfish"; break;
2667 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
2668 cipher_string = "single-DES"; break;
2670 if (s->supported_ciphers_mask & (1 << s->cipher_type))
2674 if (!cipher_chosen) {
2675 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
2676 bombout(("Server violates SSH 1 protocol by not "
2677 "supporting 3DES encryption"));
2679 /* shouldn't happen */
2680 bombout(("No supported ciphers found"));
2684 /* Warn about chosen cipher if necessary. */
2686 askcipher(ssh->frontend, cipher_string, 0);
2689 switch (s->cipher_type) {
2690 case SSH_CIPHER_3DES:
2691 logevent("Using 3DES encryption");
2693 case SSH_CIPHER_DES:
2694 logevent("Using single-DES encryption");
2696 case SSH_CIPHER_BLOWFISH:
2697 logevent("Using Blowfish encryption");
2701 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2702 PKT_CHAR, s->cipher_type,
2703 PKT_DATA, cookie, 8,
2704 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2705 PKT_DATA, s->rsabuf, s->len,
2706 PKT_INT, ssh->v1_local_protoflags, PKT_END);
2708 logevent("Trying to enable encryption...");
2712 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2713 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2715 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2716 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
2717 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
2719 ssh->crcda_ctx = crcda_make_context();
2720 logevent("Installing CRC compensation attack detector");
2722 if (servkey.modulus) {
2723 sfree(servkey.modulus);
2724 servkey.modulus = NULL;
2726 if (servkey.exponent) {
2727 sfree(servkey.exponent);
2728 servkey.exponent = NULL;
2730 if (hostkey.modulus) {
2731 sfree(hostkey.modulus);
2732 hostkey.modulus = NULL;
2734 if (hostkey.exponent) {
2735 sfree(hostkey.exponent);
2736 hostkey.exponent = NULL;
2740 if (pktin->type != SSH1_SMSG_SUCCESS) {
2741 bombout(("Encryption not successfully enabled"));
2745 logevent("Successfully started encryption");
2749 if (!*ssh->cfg.username) {
2750 if (ssh_get_line && !ssh_getline_pw_only) {
2751 if (!ssh_get_line("login as: ",
2752 s->username, sizeof(s->username), FALSE)) {
2754 * get_line failed to get a username.
2757 logevent("No username provided. Abandoning session.");
2758 ssh_closing((Plug)ssh, NULL, 0, 0);
2762 int ret; /* need not be kept over crReturn */
2763 c_write_str(ssh, "login as: ");
2766 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
2768 crWaitUntil(!pktin);
2769 ret = process_userpass_input(ssh, in, inlen);
2773 c_write_str(ssh, "\r\n");
2776 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
2777 s->username[sizeof(s->username)-1] = '\0';
2780 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
2782 char userlog[22 + sizeof(s->username)];
2783 sprintf(userlog, "Sent username \"%s\"", s->username);
2785 if (flags & FLAG_INTERACTIVE &&
2786 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
2787 strcat(userlog, "\r\n");
2788 c_write_str(ssh, userlog);
2795 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
2796 /* We must not attempt PK auth. Pretend we've already tried it. */
2797 s->tried_publickey = s->tried_agent = 1;
2799 s->tried_publickey = s->tried_agent = 0;
2801 s->tis_auth_refused = s->ccard_auth_refused = 0;
2802 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2803 if (!filename_is_null(ssh->cfg.keyfile)) {
2804 if (!rsakey_pubblob(&ssh->cfg.keyfile,
2805 &s->publickey_blob, &s->publickey_bloblen, NULL))
2806 s->publickey_blob = NULL;
2808 s->publickey_blob = NULL;
2810 while (pktin->type == SSH1_SMSG_FAILURE) {
2811 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
2813 if (agent_exists() && !s->tried_agent) {
2815 * Attempt RSA authentication using Pageant.
2821 logevent("Pageant is running. Requesting keys.");
2823 /* Request the keys held by the agent. */
2824 PUT_32BIT(s->request, 1);
2825 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
2826 if (!agent_query(s->request, 5, &r, &s->responselen,
2827 ssh_agent_callback, ssh)) {
2831 bombout(("Unexpected data from server while waiting"
2832 " for agent response"));
2835 } while (pktin || inlen > 0);
2836 r = ssh->agent_response;
2837 s->responselen = ssh->agent_response_len;
2839 s->response = (unsigned char *) r;
2840 if (s->response && s->responselen >= 5 &&
2841 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2842 s->p = s->response + 5;
2843 s->nkeys = GET_32BIT(s->p);
2847 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
2850 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2853 sprintf(buf, "Trying Pageant key #%d", s->keyi);
2856 if (s->publickey_blob &&
2857 !memcmp(s->p, s->publickey_blob,
2858 s->publickey_bloblen)) {
2859 logevent("This key matches configured key file");
2860 s->tried_publickey = 1;
2865 do { /* do while (0) to make breaking easy */
2866 n = ssh1_read_bignum
2867 (s->p, s->responselen-(s->p-s->response),
2872 n = ssh1_read_bignum
2873 (s->p, s->responselen-(s->p-s->response),
2878 if (s->responselen - (s->p-s->response) < 4)
2880 s->commentlen = GET_32BIT(s->p);
2882 if (s->responselen - (s->p-s->response) <
2885 s->commentp = (char *)s->p;
2886 s->p += s->commentlen;
2890 logevent("Pageant key list packet was truncated");
2894 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2895 PKT_BIGNUM, s->key.modulus, PKT_END);
2897 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
2898 logevent("Key refused");
2901 logevent("Received RSA challenge");
2902 if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
2903 bombout(("Server's RSA challenge was badly formatted"));
2908 char *agentreq, *q, *ret;
2911 len = 1 + 4; /* message type, bit count */
2912 len += ssh1_bignum_length(s->key.exponent);
2913 len += ssh1_bignum_length(s->key.modulus);
2914 len += ssh1_bignum_length(s->challenge);
2915 len += 16; /* session id */
2916 len += 4; /* response format */
2917 agentreq = snewn(4 + len, char);
2918 PUT_32BIT(agentreq, len);
2920 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
2921 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
2923 q += ssh1_write_bignum(q, s->key.exponent);
2924 q += ssh1_write_bignum(q, s->key.modulus);
2925 q += ssh1_write_bignum(q, s->challenge);
2926 memcpy(q, s->session_id, 16);
2928 PUT_32BIT(q, 1); /* response format */
2929 if (!agent_query(agentreq, len + 4, &vret, &retlen,
2930 ssh_agent_callback, ssh)) {
2935 bombout(("Unexpected data from server"
2936 " while waiting for agent"
2940 } while (pktin || inlen > 0);
2941 vret = ssh->agent_response;
2942 retlen = ssh->agent_response_len;
2947 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2948 logevent("Sending Pageant's response");
2949 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
2950 PKT_DATA, ret + 5, 16,
2954 if (pktin->type == SSH1_SMSG_SUCCESS) {
2956 ("Pageant's response accepted");
2957 if (flags & FLAG_VERBOSE) {
2958 c_write_str(ssh, "Authenticated using"
2960 c_write(ssh, s->commentp,
2962 c_write_str(ssh, "\" from agent\r\n");
2967 ("Pageant's response not accepted");
2970 ("Pageant failed to answer challenge");
2974 logevent("No reply received from Pageant");
2977 freebn(s->key.exponent);
2978 freebn(s->key.modulus);
2979 freebn(s->challenge);
2988 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
2989 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
2991 if (ssh->cfg.try_tis_auth &&
2992 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2993 !s->tis_auth_refused) {
2994 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
2995 logevent("Requested TIS authentication");
2996 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
2998 if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
2999 logevent("TIS authentication declined");
3000 if (flags & FLAG_INTERACTIVE)
3001 c_write_str(ssh, "TIS authentication refused.\r\n");
3002 s->tis_auth_refused = 1;
3008 ssh_pkt_getstring(pktin, &challenge, &challengelen);
3010 bombout(("TIS challenge packet was badly formed"));
3013 logevent("Received TIS challenge");
3014 if (challengelen > sizeof(s->prompt) - 1)
3015 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
3016 memcpy(s->prompt, challenge, challengelen);
3017 /* Prompt heuristic comes from OpenSSH */
3018 strncpy(s->prompt + challengelen,
3019 memchr(s->prompt, '\n', challengelen) ?
3020 "": "\r\nResponse: ",
3021 (sizeof s->prompt) - challengelen);
3022 s->prompt[(sizeof s->prompt) - 1] = '\0';
3025 if (ssh->cfg.try_tis_auth &&
3026 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
3027 !s->ccard_auth_refused) {
3028 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
3029 logevent("Requested CryptoCard authentication");
3030 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
3032 if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
3033 logevent("CryptoCard authentication declined");
3034 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
3035 s->ccard_auth_refused = 1;
3041 ssh_pkt_getstring(pktin, &challenge, &challengelen);
3043 bombout(("CryptoCard challenge packet was badly formed"));
3046 logevent("Received CryptoCard challenge");
3047 if (challengelen > sizeof(s->prompt) - 1)
3048 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
3049 memcpy(s->prompt, challenge, challengelen);
3050 strncpy(s->prompt + challengelen,
3051 memchr(s->prompt, '\n', challengelen) ?
3052 "" : "\r\nResponse: ",
3053 sizeof(s->prompt) - challengelen);
3054 s->prompt[sizeof(s->prompt) - 1] = '\0';
3057 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3058 sprintf(s->prompt, "%.90s@%.90s's password: ",
3059 s->username, ssh->savedhost);
3061 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
3062 char *comment = NULL;
3065 if (flags & FLAG_VERBOSE)
3066 c_write_str(ssh, "Trying public key authentication.\r\n");
3067 logeventf(ssh, "Trying public key \"%s\"",
3068 filename_to_str(&ssh->cfg.keyfile));
3069 type = key_type(&ssh->cfg.keyfile);
3070 if (type != SSH_KEYTYPE_SSH1) {
3071 sprintf(msgbuf, "Key is of wrong type (%s)",
3072 key_type_to_str(type));
3074 c_write_str(ssh, msgbuf);
3075 c_write_str(ssh, "\r\n");
3076 s->tried_publickey = 1;
3079 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
3080 if (flags & FLAG_VERBOSE)
3081 c_write_str(ssh, "No passphrase required.\r\n");
3084 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
3089 * Show password prompt, having first obtained it via a TIS
3090 * or CryptoCard exchange if we're doing TIS or CryptoCard
3094 if (!ssh_get_line(s->prompt, s->password,
3095 sizeof(s->password), TRUE)) {
3097 * get_line failed to get a password (for example
3098 * because one was supplied on the command line
3099 * which has already failed to work). Terminate.
3101 send_packet(ssh, SSH1_MSG_DISCONNECT,
3102 PKT_STR, "No more passwords available to try",
3104 logevent("Unable to authenticate");
3105 connection_fatal(ssh->frontend, "Unable to authenticate");
3106 ssh_closing((Plug)ssh, NULL, 0, 0);
3110 /* Prompt may have come from server. We've munged it a bit, so
3111 * we know it to be zero-terminated at least once. */
3112 int ret; /* need not be saved over crReturn */
3113 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3116 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
3118 crWaitUntil(!pktin);
3119 ret = process_userpass_input(ssh, in, inlen);
3123 c_write_str(ssh, "\r\n");
3127 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
3129 * Try public key authentication with the specified
3132 s->tried_publickey = 1;
3135 const char *error = NULL;
3136 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3139 c_write_str(ssh, "Couldn't load private key from ");
3140 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
3141 c_write_str(ssh, " (");
3142 c_write_str(ssh, error);
3143 c_write_str(ssh, ").\r\n");
3144 continue; /* go and try password */
3147 c_write_str(ssh, "Wrong passphrase.\r\n");
3148 s->tried_publickey = 0;
3149 continue; /* try again */
3154 * Send a public key attempt.
3156 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3157 PKT_BIGNUM, s->key.modulus, PKT_END);
3160 if (pktin->type == SSH1_SMSG_FAILURE) {
3161 c_write_str(ssh, "Server refused our public key.\r\n");
3162 continue; /* go and try password */
3164 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
3165 bombout(("Bizarre response to offer of public key"));
3171 unsigned char buffer[32];
3172 Bignum challenge, response;
3174 if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
3175 bombout(("Server's RSA challenge was badly formatted"));
3178 response = rsadecrypt(challenge, &s->key);
3179 freebn(s->key.private_exponent);/* burn the evidence */
3181 for (i = 0; i < 32; i++) {
3182 buffer[i] = bignum_byte(response, 31 - i);
3186 MD5Update(&md5c, buffer, 32);
3187 MD5Update(&md5c, s->session_id, 16);
3188 MD5Final(buffer, &md5c);
3190 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3191 PKT_DATA, buffer, 16, PKT_END);
3198 if (pktin->type == SSH1_SMSG_FAILURE) {
3199 if (flags & FLAG_VERBOSE)
3200 c_write_str(ssh, "Failed to authenticate with"
3201 " our public key.\r\n");
3202 continue; /* go and try password */
3203 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3204 bombout(("Bizarre response to RSA authentication response"));
3208 break; /* we're through! */
3210 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3212 * Defence against traffic analysis: we send a
3213 * whole bunch of packets containing strings of
3214 * different lengths. One of these strings is the
3215 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3216 * The others are all random data in
3217 * SSH1_MSG_IGNORE packets. This way a passive
3218 * listener can't tell which is the password, and
3219 * hence can't deduce the password length.
3221 * Anybody with a password length greater than 16
3222 * bytes is going to have enough entropy in their
3223 * password that a listener won't find it _that_
3224 * much help to know how long it is. So what we'll
3227 * - if password length < 16, we send 15 packets
3228 * containing string lengths 1 through 15
3230 * - otherwise, we let N be the nearest multiple
3231 * of 8 below the password length, and send 8
3232 * packets containing string lengths N through
3233 * N+7. This won't obscure the order of
3234 * magnitude of the password length, but it will
3235 * introduce a bit of extra uncertainty.
3237 * A few servers (the old 1.2.18 through 1.2.22)
3238 * can't deal with SSH1_MSG_IGNORE. For these
3239 * servers, we need an alternative defence. We make
3240 * use of the fact that the password is interpreted
3241 * as a C string: so we can append a NUL, then some
3244 * One server (a Cisco one) can deal with neither
3245 * SSH1_MSG_IGNORE _nor_ a padded password string.
3246 * For this server we are left with no defences
3247 * against password length sniffing.
3249 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
3251 * The server can deal with SSH1_MSG_IGNORE, so
3252 * we can use the primary defence.
3254 int bottom, top, pwlen, i;
3257 pwlen = strlen(s->password);
3259 bottom = 0; /* zero length passwords are OK! :-) */
3262 bottom = pwlen & ~7;
3266 assert(pwlen >= bottom && pwlen <= top);
3268 randomstr = snewn(top + 1, char);
3270 for (i = bottom; i <= top; i++) {
3272 defer_packet(ssh, s->pwpkt_type,
3273 PKTT_PASSWORD, PKT_STR, s->password,
3274 PKTT_OTHER, PKT_END);
3276 for (j = 0; j < i; j++) {
3278 randomstr[j] = random_byte();
3279 } while (randomstr[j] == '\0');
3281 randomstr[i] = '\0';
3282 defer_packet(ssh, SSH1_MSG_IGNORE,
3283 PKT_STR, randomstr, PKT_END);
3286 logevent("Sending password with camouflage packets");
3287 ssh_pkt_defersend(ssh);
3290 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
3292 * The server can't deal with SSH1_MSG_IGNORE
3293 * but can deal with padded passwords, so we
3294 * can use the secondary defence.
3300 len = strlen(s->password);
3301 if (len < sizeof(string)) {
3303 strcpy(string, s->password);
3304 len++; /* cover the zero byte */
3305 while (len < sizeof(string)) {
3306 string[len++] = (char) random_byte();
3311 logevent("Sending length-padded password");
3312 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3313 PKT_INT, len, PKT_DATA, ss, len,
3314 PKTT_OTHER, PKT_END);
3317 * The server has _both_
3318 * BUG_CHOKES_ON_SSH1_IGNORE and
3319 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3320 * therefore nothing we can do.
3323 len = strlen(s->password);
3324 logevent("Sending unpadded password");
3325 send_packet(ssh, s->pwpkt_type,
3326 PKTT_PASSWORD, PKT_INT, len,
3327 PKT_DATA, s->password, len,
3328 PKTT_OTHER, PKT_END);
3331 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3332 PKT_STR, s->password, PKTT_OTHER, PKT_END);
3335 logevent("Sent password");
3336 memset(s->password, 0, strlen(s->password));
3338 if (pktin->type == SSH1_SMSG_FAILURE) {
3339 if (flags & FLAG_VERBOSE)
3340 c_write_str(ssh, "Access denied\r\n");
3341 logevent("Authentication refused");
3342 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3343 bombout(("Strange packet received, type %d", pktin->type));
3348 logevent("Authentication successful");
3353 void sshfwd_close(struct ssh_channel *c)
3357 if (ssh->state != SSH_STATE_SESSION) {
3358 assert(ssh->state == SSH_STATE_CLOSED);
3362 if (c && !c->closes) {
3364 * If the channel's remoteid is -1, we have sent
3365 * CHANNEL_OPEN for this channel, but it hasn't even been
3366 * acknowledged by the server. So we must set a close flag
3367 * on it now, and then when the server acks the channel
3368 * open, we can close it then.
3370 if (((int)c->remoteid) != -1) {
3371 if (ssh->version == 1) {
3372 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
3375 struct Packet *pktout;
3376 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3377 ssh2_pkt_adduint32(pktout, c->remoteid);
3378 ssh2_pkt_send(ssh, pktout);
3381 c->closes = 1; /* sent MSG_CLOSE */
3382 if (c->type == CHAN_X11) {
3384 logevent("Forwarded X11 connection terminated");
3385 } else if (c->type == CHAN_SOCKDATA ||
3386 c->type == CHAN_SOCKDATA_DORMANT) {
3388 logevent("Forwarded port closed");
3393 int sshfwd_write(struct ssh_channel *c, char *buf, int len)
3397 if (ssh->state != SSH_STATE_SESSION) {
3398 assert(ssh->state == SSH_STATE_CLOSED);
3402 if (ssh->version == 1) {
3403 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
3404 PKT_INT, c->remoteid,
3406 PKT_INT, len, PKT_DATA, buf, len,
3407 PKTT_OTHER, PKT_END);
3409 * In SSH1 we can return 0 here - implying that forwarded
3410 * connections are never individually throttled - because
3411 * the only circumstance that can cause throttling will be
3412 * the whole SSH connection backing up, in which case
3413 * _everything_ will be throttled as a whole.
3417 ssh2_add_channel_data(c, buf, len);
3418 return ssh2_try_send(c);
3422 void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3426 if (ssh->state != SSH_STATE_SESSION) {
3427 assert(ssh->state == SSH_STATE_CLOSED);
3431 if (ssh->version == 1) {
3432 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3433 c->v.v1.throttling = 0;
3434 ssh1_throttle(ssh, -1);
3437 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
3441 static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
3442 struct Packet *pktin)
3444 crBegin(ssh->do_ssh1_connection_crstate);
3446 if (ssh->cfg.agentfwd && agent_exists()) {
3447 logevent("Requesting agent forwarding");
3448 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
3452 if (pktin->type != SSH1_SMSG_SUCCESS
3453 && pktin->type != SSH1_SMSG_FAILURE) {
3454 bombout(("Protocol confusion"));
3456 } else if (pktin->type == SSH1_SMSG_FAILURE) {
3457 logevent("Agent forwarding refused");
3459 logevent("Agent forwarding enabled");
3460 ssh->agentfwd_enabled = TRUE;
3464 if (ssh->cfg.x11_forward) {
3465 char proto[20], data[64];
3466 logevent("Requesting X11 forwarding");
3467 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
3468 data, sizeof(data), ssh->cfg.x11_auth);
3469 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
3470 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
3471 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
3472 PKT_STR, proto, PKT_STR, data,
3473 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
3476 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
3477 PKT_STR, proto, PKT_STR, data, PKT_END);
3482 if (pktin->type != SSH1_SMSG_SUCCESS
3483 && pktin->type != SSH1_SMSG_FAILURE) {
3484 bombout(("Protocol confusion"));
3486 } else if (pktin->type == SSH1_SMSG_FAILURE) {
3487 logevent("X11 forwarding refused");
3489 logevent("X11 forwarding enabled");
3490 ssh->X11_fwd_enabled = TRUE;
3497 int sport,dport,sserv,dserv;
3498 char sports[256], dports[256], saddr[256], host[256];
3500 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
3501 /* Add port forwardings. */
3502 ssh->portfwd_strptr = ssh->cfg.portfwd;
3503 while (*ssh->portfwd_strptr) {
3504 type = *ssh->portfwd_strptr++;
3507 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
3508 if (*ssh->portfwd_strptr == ':') {
3510 * We've seen a colon in the middle of the
3511 * source port number. This means that
3512 * everything we've seen until now is the
3513 * source _address_, so we'll move it into
3514 * saddr and start sports from the beginning
3517 ssh->portfwd_strptr++;
3519 strcpy(saddr, sports);
3522 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
3526 if (*ssh->portfwd_strptr == '\t')
3527 ssh->portfwd_strptr++;
3529 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
3530 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
3533 if (*ssh->portfwd_strptr == ':')
3534 ssh->portfwd_strptr++;
3536 while (*ssh->portfwd_strptr) {
3537 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
3540 ssh->portfwd_strptr++;
3541 dport = atoi(dports);
3545 dport = net_service_lookup(dports);
3547 logeventf(ssh, "Service lookup failed for"
3548 " destination port \"%s\"", dports);
3552 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
3554 ssh->portfwd_strptr++; /* eat the NUL and move to next one */
3556 sport = atoi(sports);
3560 sport = net_service_lookup(sports);
3562 logeventf(ssh, "Service lookup failed for source"
3563 " port \"%s\"", sports);
3566 if (sport && dport) {
3567 /* Set up a description of the source port. */
3568 static char *sportdesc;
3569 sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3570 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3571 (int)(*saddr?1:0), ":",
3572 (int)(sserv ? strlen(sports) : 0), sports,
3573 sserv, "(", sport, sserv, ")");
3575 /* Verbose description of the destination port */
3576 char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
3578 (int)(dserv ? strlen(dports) : 0), dports,
3579 dserv, "(", dport, dserv, ")");
3580 const char *err = pfd_addforward(host, dport,
3581 *saddr ? saddr : NULL,
3582 sport, ssh, &ssh->cfg);
3584 logeventf(ssh, "Local port %s forward to %s"
3585 " failed: %s", sportdesc, dportdesc, err);
3587 logeventf(ssh, "Local port %s forwarding to %s",
3588 sportdesc, dportdesc);
3591 } else if (type == 'D') {
3592 const char *err = pfd_addforward(NULL, -1,
3593 *saddr ? saddr : NULL,
3594 sport, ssh, &ssh->cfg);
3596 logeventf(ssh, "Local port %s SOCKS dynamic forward"
3597 " setup failed: %s", sportdesc, err);
3599 logeventf(ssh, "Local port %s doing SOCKS"
3600 " dynamic forwarding", sportdesc);
3603 struct ssh_rportfwd *pf;
3604 pf = snew(struct ssh_rportfwd);
3605 strcpy(pf->dhost, host);
3609 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3612 if (add234(ssh->rportfwds, pf) != pf) {
3614 "Duplicate remote port forwarding to %s:%d",
3618 logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
3619 " forward to %s:%.*s%.*s%d%.*s",
3620 (int)(sserv ? strlen(sports) : 0), sports,
3621 sserv, "(", sport, sserv, ")",
3623 (int)(dserv ? strlen(dports) : 0), dports,
3624 dserv, "(", dport, dserv, ")");
3625 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
3633 if (pktin->type != SSH1_SMSG_SUCCESS
3634 && pktin->type != SSH1_SMSG_FAILURE) {
3635 bombout(("Protocol confusion"));
3637 } else if (pktin->type == SSH1_SMSG_FAILURE) {
3638 c_write_str(ssh, "Server refused port"
3641 logevent("Remote port forwarding enabled");
3649 if (!ssh->cfg.nopty) {
3650 /* Unpick the terminal-speed string. */
3651 /* XXX perhaps we should allow no speeds to be sent. */
3652 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
3653 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
3654 /* Send the pty request. */
3655 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
3656 PKT_STR, ssh->cfg.termtype,
3657 PKT_INT, ssh->term_height,
3658 PKT_INT, ssh->term_width,
3659 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
3660 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
3661 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
3662 PKT_CHAR, 0, PKT_END);
3663 ssh->state = SSH_STATE_INTERMED;
3667 if (pktin->type != SSH1_SMSG_SUCCESS
3668 && pktin->type != SSH1_SMSG_FAILURE) {
3669 bombout(("Protocol confusion"));
3671 } else if (pktin->type == SSH1_SMSG_FAILURE) {
3672 c_write_str(ssh, "Server refused to allocate pty\r\n");
3673 ssh->editing = ssh->echoing = 1;
3675 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
3676 ssh->ospeed, ssh->ispeed);
3678 ssh->editing = ssh->echoing = 1;
3681 if (ssh->cfg.compression) {
3682 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
3686 if (pktin->type != SSH1_SMSG_SUCCESS
3687 && pktin->type != SSH1_SMSG_FAILURE) {
3688 bombout(("Protocol confusion"));
3690 } else if (pktin->type == SSH1_SMSG_FAILURE) {
3691 c_write_str(ssh, "Server refused to compress\r\n");
3693 logevent("Started compression");
3694 ssh->v1_compressing = TRUE;
3695 ssh->cs_comp_ctx = zlib_compress_init();
3696 logevent("Initialised zlib (RFC1950) compression");
3697 ssh->sc_comp_ctx = zlib_decompress_init();
3698 logevent("Initialised zlib (RFC1950) decompression");
3702 * Start the shell or command.
3704 * Special case: if the first-choice command is an SSH2
3705 * subsystem (hence not usable here) and the second choice
3706 * exists, we fall straight back to that.
3709 char *cmd = ssh->cfg.remote_cmd_ptr;
3711 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
3712 cmd = ssh->cfg.remote_cmd_ptr2;
3713 ssh->fallback_cmd = TRUE;
3716 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
3718 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
3719 logevent("Started session");
3722 ssh->state = SSH_STATE_SESSION;
3723 if (ssh->size_needed)
3724 ssh_size(ssh, ssh->term_width, ssh->term_height);
3725 if (ssh->eof_needed)
3726 ssh_special(ssh, TS_EOF);
3729 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
3731 ssh->channels = newtree234(ssh_channelcmp);
3735 if (pktin->type == SSH1_SMSG_STDOUT_DATA ||
3736 pktin->type == SSH1_SMSG_STDERR_DATA) {
3738 int stringlen, bufsize;
3740 ssh_pkt_getstring(pktin, &string, &stringlen);
3741 if (string == NULL) {
3742 bombout(("Incoming terminal data packet was badly formed"));
3747 from_backend(ssh->frontend,
3748 pktin->type == SSH1_SMSG_STDERR_DATA,
3750 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
3751 ssh->v1_stdout_throttling = 1;
3752 ssh1_throttle(ssh, +1);
3754 } else if (pktin->type == SSH1_MSG_DISCONNECT) {
3755 ssh_closing((Plug)ssh, NULL, 0, 0);
3756 logevent("Received disconnect request");
3758 } else if (pktin->type == SSH1_SMSG_X11_OPEN) {
3759 /* Remote side is trying to open a channel to talk to our
3760 * X-Server. Give them back a local channel number. */
3761 struct ssh_channel *c;
3762 int remoteid = ssh_pkt_getuint32(pktin);
3764 logevent("Received X11 connect request");
3765 /* Refuse if X11 forwarding is disabled. */
3766 if (!ssh->X11_fwd_enabled) {
3767 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3768 PKT_INT, remoteid, PKT_END);
3769 logevent("Rejected X11 connect request");
3771 c = snew(struct ssh_channel);
3774 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
3775 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
3776 logevent("Opening X11 forward connection failed");
3778 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3779 PKT_INT, remoteid, PKT_END);
3782 ("Opening X11 forward connection succeeded");
3783 c->remoteid = remoteid;
3784 c->localid = alloc_channel_id(ssh);
3786 c->v.v1.throttling = 0;
3787 c->type = CHAN_X11; /* identify channel type */
3788 add234(ssh->channels, c);
3789 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3790 PKT_INT, c->remoteid, PKT_INT,
3791 c->localid, PKT_END);
3792 logevent("Opened X11 forward channel");
3795 } else if (pktin->type == SSH1_SMSG_AGENT_OPEN) {
3796 /* Remote side is trying to open a channel to talk to our
3797 * agent. Give them back a local channel number. */
3798 struct ssh_channel *c;
3799 int remoteid = ssh_pkt_getuint32(pktin);
3801 /* Refuse if agent forwarding is disabled. */
3802 if (!ssh->agentfwd_enabled) {
3803 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3804 PKT_INT, remoteid, PKT_END);
3806 c = snew(struct ssh_channel);
3808 c->remoteid = remoteid;
3809 c->localid = alloc_channel_id(ssh);
3811 c->v.v1.throttling = 0;
3812 c->type = CHAN_AGENT; /* identify channel type */
3813 c->u.a.lensofar = 0;
3814 add234(ssh->channels, c);
3815 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3816 PKT_INT, c->remoteid, PKT_INT, c->localid,
3819 } else if (pktin->type == SSH1_MSG_PORT_OPEN) {
3820 /* Remote side is trying to open a channel to talk to a
3821 * forwarded port. Give them back a local channel number. */
3822 struct ssh_channel *c;
3823 struct ssh_rportfwd pf;
3826 char *host, buf[1024];
3828 c = snew(struct ssh_channel);
3831 remoteid = ssh_pkt_getuint32(pktin);
3832 ssh_pkt_getstring(pktin, &host, &hostsize);
3833 port = ssh_pkt_getuint32(pktin);
3835 if (hostsize >= lenof(pf.dhost))
3836 hostsize = lenof(pf.dhost)-1;
3837 memcpy(pf.dhost, host, hostsize);
3838 pf.dhost[hostsize] = '\0';
3841 if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
3842 sprintf(buf, "Rejected remote port open request for %s:%d",
3845 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3846 PKT_INT, remoteid, PKT_END);
3848 sprintf(buf, "Received remote port open request for %s:%d",
3851 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
3855 sprintf(buf, "Port open failed: %s", e);
3858 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3859 PKT_INT, remoteid, PKT_END);
3861 c->remoteid = remoteid;
3862 c->localid = alloc_channel_id(ssh);
3864 c->v.v1.throttling = 0;
3865 c->type = CHAN_SOCKDATA; /* identify channel type */
3866 add234(ssh->channels, c);
3867 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3868 PKT_INT, c->remoteid, PKT_INT,
3869 c->localid, PKT_END);
3870 logevent("Forwarded port opened successfully");
3874 } else if (pktin->type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
3875 unsigned int remoteid = ssh_pkt_getuint32(pktin);
3876 unsigned int localid = ssh_pkt_getuint32(pktin);
3877 struct ssh_channel *c;
3879 c = find234(ssh->channels, &remoteid, ssh_channelfind);
3880 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3881 c->remoteid = localid;
3882 c->type = CHAN_SOCKDATA;
3883 c->v.v1.throttling = 0;
3884 pfd_confirm(c->u.pfd.s);
3887 if (c && c->closes) {
3889 * We have a pending close on this channel,
3890 * which we decided on before the server acked
3891 * the channel open. So now we know the
3892 * remoteid, we can close it again.
3894 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
3895 PKT_INT, c->remoteid, PKT_END);
3898 } else if (pktin->type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
3899 unsigned int remoteid = ssh_pkt_getuint32(pktin);
3900 struct ssh_channel *c;
3902 c = find234(ssh->channels, &remoteid, ssh_channelfind);
3903 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3904 logevent("Forwarded connection refused by server");
3905 pfd_close(c->u.pfd.s);
3906 del234(ssh->channels, c);
3910 } else if (pktin->type == SSH1_MSG_CHANNEL_CLOSE ||
3911 pktin->type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
3912 /* Remote side closes a channel. */
3913 unsigned i = ssh_pkt_getuint32(pktin);
3914 struct ssh_channel *c;
3915 c = find234(ssh->channels, &i, ssh_channelfind);
3916 if (c && ((int)c->remoteid) != -1) {
3919 (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
3921 if ((c->closes == 0) && (c->type == CHAN_X11)) {
3922 logevent("Forwarded X11 connection terminated");
3923 assert(c->u.x11.s != NULL);
3924 x11_close(c->u.x11.s);
3927 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3928 logevent("Forwarded port closed");
3929 assert(c->u.pfd.s != NULL);
3930 pfd_close(c->u.pfd.s);
3934 c->closes |= (closetype << 2); /* seen this message */
3935 if (!(c->closes & closetype)) {
3936 send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
3938 c->closes |= closetype; /* sent it too */
3941 if (c->closes == 15) {
3942 del234(ssh->channels, c);
3946 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3947 pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
3948 "_CONFIRMATION", c ? "half-open" : "nonexistent",
3952 } else if (pktin->type == SSH1_MSG_CHANNEL_DATA) {
3953 /* Data sent down one of our channels. */
3954 int i = ssh_pkt_getuint32(pktin);
3957 struct ssh_channel *c;
3959 ssh_pkt_getstring(pktin, &p, &len);
3961 c = find234(ssh->channels, &i, ssh_channelfind);
3966 bufsize = x11_send(c->u.x11.s, p, len);
3969 bufsize = pfd_send(c->u.pfd.s, p, len);
3972 /* Data for an agent message. Buffer it. */
3974 if (c->u.a.lensofar < 4) {
3975 int l = min(4 - c->u.a.lensofar, len);
3976 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3980 c->u.a.lensofar += l;
3982 if (c->u.a.lensofar == 4) {
3984 4 + GET_32BIT(c->u.a.msglen);
3985 c->u.a.message = snewn(c->u.a.totallen,
3987 memcpy(c->u.a.message, c->u.a.msglen, 4);
3989 if (c->u.a.lensofar >= 4 && len > 0) {
3991 min(c->u.a.totallen - c->u.a.lensofar,
3993 memcpy(c->u.a.message + c->u.a.lensofar, p,
3997 c->u.a.lensofar += l;
3999 if (c->u.a.lensofar == c->u.a.totallen) {
4002 if (agent_query(c->u.a.message,
4005 ssh_agentf_callback, c))
4006 ssh_agentf_callback(c, reply, replylen);
4007 sfree(c->u.a.message);
4008 c->u.a.lensofar = 0;
4011 bufsize = 0; /* agent channels never back up */
4014 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
4015 c->v.v1.throttling = 1;
4016 ssh1_throttle(ssh, +1);
4019 } else if (pktin->type == SSH1_SMSG_SUCCESS) {
4020 /* may be from EXEC_SHELL on some servers */
4021 } else if (pktin->type == SSH1_SMSG_FAILURE) {
4022 /* may be from EXEC_SHELL on some servers
4023 * if no pty is available or in other odd cases. Ignore */
4024 } else if (pktin->type == SSH1_SMSG_EXIT_STATUS) {
4026 ssh->exitcode = ssh_pkt_getuint32(pktin);
4027 sprintf(buf, "Server sent command exit status %d",
4030 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4032 * In case `helpful' firewalls or proxies tack
4033 * extra human-readable text on the end of the
4034 * session which we might mistake for another
4035 * encrypted packet, we close the session once
4036 * we've sent EXIT_CONFIRMATION.
4038 ssh_closing((Plug)ssh, NULL, 0, 0);
4041 bombout(("Strange packet received: type %d", pktin->type));
4046 int len = min(inlen, 512);
4047 send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
4048 PKT_INT, len, PKT_DATA, in, len,
4049 PKTT_OTHER, PKT_END);
4060 * Handle the top-level SSH2 protocol.
4062 static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
4067 ssh_pkt_getstring(pktin, &msg, &msglen);
4068 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
4073 static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
4075 /* log reason code in disconnect message */
4079 ssh_pkt_getstring(pktin, &msg, &msglen);
4080 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
4083 void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
4085 /* Do nothing, because we're ignoring it! Duhh. */
4088 static void ssh1_protocol_setup(Ssh ssh)
4093 * Most messages are handled by the coroutines.
4095 for (i = 0; i < 256; i++)
4096 ssh->packet_dispatch[i] = NULL;
4099 * These special message types we install handlers for.
4101 ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
4102 ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
4103 ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
4106 static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
4107 struct Packet *pktin)
4109 if (ssh->state == SSH_STATE_CLOSED)
4112 if (pktin && ssh->packet_dispatch[pktin->type]) {
4113 ssh->packet_dispatch[pktin->type](ssh, pktin);
4117 if (!ssh->protocol_initial_phase_done) {
4118 if (do_ssh1_login(ssh, in, inlen, pktin))
4119 ssh->protocol_initial_phase_done = TRUE;
4124 do_ssh1_connection(ssh, in, inlen, pktin);
4128 * Utility routine for decoding comma-separated strings in KEXINIT.
4130 static int in_commasep_string(char *needle, char *haystack, int haylen)
4133 if (!needle || !haystack) /* protect against null pointers */
4135 needlen = strlen(needle);
4138 * Is it at the start of the string?
4140 if (haylen >= needlen && /* haystack is long enough */
4141 !memcmp(needle, haystack, needlen) && /* initial match */
4142 (haylen == needlen || haystack[needlen] == ',')
4143 /* either , or EOS follows */
4147 * If not, search for the next comma and resume after that.
4148 * If no comma found, terminate.
4150 while (haylen > 0 && *haystack != ',')
4151 haylen--, haystack++;
4154 haylen--, haystack++; /* skip over comma itself */
4159 * SSH2 key creation method.
4161 static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
4162 unsigned char *sessid, char chr,
4163 unsigned char *keyspace)
4166 /* First 20 bytes. */
4168 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
4170 SHA_Bytes(&s, H, 20);
4171 SHA_Bytes(&s, &chr, 1);
4172 SHA_Bytes(&s, sessid, 20);
4173 SHA_Final(&s, keyspace);
4174 /* Next 20 bytes. */
4176 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
4178 SHA_Bytes(&s, H, 20);
4179 SHA_Bytes(&s, keyspace, 20);
4180 SHA_Final(&s, keyspace + 20);
4184 * Handle the SSH2 transport layer.
4186 static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
4187 struct Packet *pktin)
4189 struct do_ssh2_transport_state {
4190 int nbits, pbits, warn;
4191 Bignum p, g, e, f, K;
4192 int kex_init_value, kex_reply_value;
4193 const struct ssh_mac **maclist;
4195 const struct ssh2_cipher *cscipher_tobe;
4196 const struct ssh2_cipher *sccipher_tobe;
4197 const struct ssh_mac *csmac_tobe;
4198 const struct ssh_mac *scmac_tobe;
4199 const struct ssh_compress *cscomp_tobe;
4200 const struct ssh_compress *sccomp_tobe;
4201 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4202 int hostkeylen, siglen;
4203 void *hkey; /* actual host key */
4204 unsigned char exchange_hash[20];
4205 int n_preferred_ciphers;
4206 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4207 const struct ssh_compress *preferred_comp;
4209 struct Packet *pktout;
4211 crState(do_ssh2_transport_state);
4213 crBegin(ssh->do_ssh2_transport_crstate);
4215 s->cscipher_tobe = s->sccipher_tobe = NULL;
4216 s->csmac_tobe = s->scmac_tobe = NULL;
4217 s->cscomp_tobe = s->sccomp_tobe = NULL;
4225 * Set up the preferred ciphers. (NULL => warn below here)
4227 s->n_preferred_ciphers = 0;
4228 for (i = 0; i < CIPHER_MAX; i++) {
4229 switch (ssh->cfg.ssh_cipherlist[i]) {
4230 case CIPHER_BLOWFISH:
4231 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4234 if (ssh->cfg.ssh2_des_cbc) {
4235 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4239 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4242 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4245 /* Flag for later. Don't bother if it's the last in
4247 if (i < CIPHER_MAX - 1) {
4248 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4256 * Set up preferred compression.
4258 if (ssh->cfg.compression)
4259 s->preferred_comp = &ssh_zlib;
4261 s->preferred_comp = &ssh_comp_none;
4264 * Be prepared to work around the buggy MAC problem.
4266 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4267 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
4269 s->maclist = macs, s->nmacs = lenof(macs);
4273 int i, j, cipherstr_started;
4276 * Enable queueing of outgoing auth- or connection-layer
4277 * packets while we are in the middle of a key exchange.
4279 ssh->queueing = TRUE;
4282 * Construct and send our key exchange packet.
4284 s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
4285 for (i = 0; i < 16; i++)
4286 ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
4287 /* List key exchange algorithms. */
4288 ssh2_pkt_addstring_start(s->pktout);
4289 for (i = 0; i < lenof(kex_algs); i++) {
4290 if (kex_algs[i] == &ssh_diffiehellman_gex &&
4291 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
4293 ssh2_pkt_addstring_str(s->pktout, kex_algs[i]->name);
4294 if (i < lenof(kex_algs) - 1)
4295 ssh2_pkt_addstring_str(s->pktout, ",");
4297 /* List server host key algorithms. */
4298 ssh2_pkt_addstring_start(s->pktout);
4299 for (i = 0; i < lenof(hostkey_algs); i++) {
4300 ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
4301 if (i < lenof(hostkey_algs) - 1)
4302 ssh2_pkt_addstring_str(s->pktout, ",");
4304 /* List client->server encryption algorithms. */
4305 ssh2_pkt_addstring_start(s->pktout);
4306 cipherstr_started = 0;
4307 for (i = 0; i < s->n_preferred_ciphers; i++) {
4308 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4309 if (!c) continue; /* warning flag */
4310 for (j = 0; j < c->nciphers; j++) {
4311 if (cipherstr_started)
4312 ssh2_pkt_addstring_str(s->pktout, ",");
4313 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
4314 cipherstr_started = 1;
4317 /* List server->client encryption algorithms. */
4318 ssh2_pkt_addstring_start(s->pktout);
4319 cipherstr_started = 0;
4320 for (i = 0; i < s->n_preferred_ciphers; i++) {
4321 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4322 if (!c) continue; /* warning flag */
4323 for (j = 0; j < c->nciphers; j++) {
4324 if (cipherstr_started)
4325 ssh2_pkt_addstring_str(s->pktout, ",");
4326 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
4327 cipherstr_started = 1;
4330 /* List client->server MAC algorithms. */
4331 ssh2_pkt_addstring_start(s->pktout);
4332 for (i = 0; i < s->nmacs; i++) {
4333 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
4334 if (i < s->nmacs - 1)
4335 ssh2_pkt_addstring_str(s->pktout, ",");
4337 /* List server->client MAC algorithms. */
4338 ssh2_pkt_addstring_start(s->pktout);
4339 for (i = 0; i < s->nmacs; i++) {
4340 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
4341 if (i < s->nmacs - 1)
4342 ssh2_pkt_addstring_str(s->pktout, ",");
4344 /* List client->server compression algorithms. */
4345 ssh2_pkt_addstring_start(s->pktout);
4346 assert(lenof(compressions) > 1);
4347 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
4348 for (i = 0; i < lenof(compressions); i++) {
4349 const struct ssh_compress *c = compressions[i];
4350 if (c != s->preferred_comp) {
4351 ssh2_pkt_addstring_str(s->pktout, ",");
4352 ssh2_pkt_addstring_str(s->pktout, c->name);
4355 /* List server->client compression algorithms. */
4356 ssh2_pkt_addstring_start(s->pktout);
4357 assert(lenof(compressions) > 1);
4358 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
4359 for (i = 0; i < lenof(compressions); i++) {
4360 const struct ssh_compress *c = compressions[i];
4361 if (c != s->preferred_comp) {
4362 ssh2_pkt_addstring_str(s->pktout, ",");
4363 ssh2_pkt_addstring_str(s->pktout, c->name);
4366 /* List client->server languages. Empty list. */
4367 ssh2_pkt_addstring_start(s->pktout);
4368 /* List server->client languages. Empty list. */
4369 ssh2_pkt_addstring_start(s->pktout);
4370 /* First KEX packet does _not_ follow, because we're not that brave. */
4371 ssh2_pkt_addbool(s->pktout, FALSE);
4373 ssh2_pkt_adduint32(s->pktout, 0);
4376 ssh->exhash = ssh->exhashbase;
4377 sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
4379 ssh2_pkt_send_noqueue(ssh, s->pktout);
4383 if (pktin->length > 5)
4384 sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
4387 * Now examine the other side's KEXINIT to see what we're up
4394 if (pktin->type != SSH2_MSG_KEXINIT) {
4395 bombout(("expected key exchange packet from server"));
4399 ssh->hostkey = NULL;
4400 s->cscipher_tobe = NULL;
4401 s->sccipher_tobe = NULL;
4402 s->csmac_tobe = NULL;
4403 s->scmac_tobe = NULL;
4404 s->cscomp_tobe = NULL;
4405 s->sccomp_tobe = NULL;
4406 pktin->savedpos += 16; /* skip garbage cookie */
4407 ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
4408 for (i = 0; i < lenof(kex_algs); i++) {
4409 if (kex_algs[i] == &ssh_diffiehellman_gex &&
4410 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
4412 if (in_commasep_string(kex_algs[i]->name, str, len)) {
4413 ssh->kex = kex_algs[i];
4417 ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
4418 for (i = 0; i < lenof(hostkey_algs); i++) {
4419 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4420 ssh->hostkey = hostkey_algs[i];
4424 ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
4426 for (i = 0; i < s->n_preferred_ciphers; i++) {
4427 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4431 for (j = 0; j < c->nciphers; j++) {
4432 if (in_commasep_string(c->list[j]->name, str, len)) {
4433 s->cscipher_tobe = c->list[j];
4438 if (s->cscipher_tobe) {
4440 askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
4444 if (!s->cscipher_tobe) {
4445 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4446 str ? str : "(null)"));
4450 ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
4452 for (i = 0; i < s->n_preferred_ciphers; i++) {
4453 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4457 for (j = 0; j < c->nciphers; j++) {
4458 if (in_commasep_string(c->list[j]->name, str, len)) {
4459 s->sccipher_tobe = c->list[j];
4464 if (s->sccipher_tobe) {
4466 askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
4470 if (!s->sccipher_tobe) {
4471 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4472 str ? str : "(null)"));
4476 ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
4477 for (i = 0; i < s->nmacs; i++) {
4478 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4479 s->csmac_tobe = s->maclist[i];
4483 ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
4484 for (i = 0; i < s->nmacs; i++) {
4485 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4486 s->scmac_tobe = s->maclist[i];
4490 ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
4491 for (i = 0; i < lenof(compressions) + 1; i++) {
4492 const struct ssh_compress *c =
4493 i == 0 ? s->preferred_comp : compressions[i - 1];
4494 if (in_commasep_string(c->name, str, len)) {
4499 ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
4500 for (i = 0; i < lenof(compressions) + 1; i++) {
4501 const struct ssh_compress *c =
4502 i == 0 ? s->preferred_comp : compressions[i - 1];
4503 if (in_commasep_string(c->name, str, len)) {
4511 * Work out the number of bits of key we will need from the key
4512 * exchange. We start with the maximum key length of either
4518 csbits = s->cscipher_tobe->keylen;
4519 scbits = s->sccipher_tobe->keylen;
4520 s->nbits = (csbits > scbits ? csbits : scbits);
4522 /* The keys only have 160-bit entropy, since they're based on
4523 * a SHA-1 hash. So cap the key size at 160 bits. */
4528 * If we're doing Diffie-Hellman group exchange, start by
4529 * requesting a group.
4531 if (ssh->kex == &ssh_diffiehellman_gex) {
4532 logevent("Doing Diffie-Hellman group exchange");
4533 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
4535 * Work out how big a DH group we will need to allow that
4538 s->pbits = 512 << ((s->nbits - 1) / 64);
4539 s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
4540 ssh2_pkt_adduint32(s->pktout, s->pbits);
4541 ssh2_pkt_send_noqueue(ssh, s->pktout);
4544 if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
4545 bombout(("expected key exchange group packet from server"));
4548 s->p = ssh2_pkt_getmp(pktin);
4549 s->g = ssh2_pkt_getmp(pktin);
4550 if (!s->p || !s->g) {
4551 bombout(("unable to read mp-ints from incoming group packet"));
4554 ssh->kex_ctx = dh_setup_group(s->p, s->g);
4555 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
4556 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
4558 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
4559 ssh->kex_ctx = dh_setup_group1();
4560 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
4561 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
4564 logevent("Doing Diffie-Hellman key exchange");
4566 * Now generate and send e for Diffie-Hellman.
4568 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
4569 s->pktout = ssh2_pkt_init(s->kex_init_value);
4570 ssh2_pkt_addmp(s->pktout, s->e);
4571 ssh2_pkt_send_noqueue(ssh, s->pktout);
4574 if (pktin->type != s->kex_reply_value) {
4575 bombout(("expected key exchange reply packet from server"));
4578 ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
4579 s->f = ssh2_pkt_getmp(pktin);
4581 bombout(("unable to parse key exchange reply packet"));
4584 ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
4586 s->K = dh_find_K(ssh->kex_ctx, s->f);
4588 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
4589 if (ssh->kex == &ssh_diffiehellman_gex) {
4590 sha_uint32(&ssh->exhash, s->pbits);
4591 sha_mpint(&ssh->exhash, s->p);
4592 sha_mpint(&ssh->exhash, s->g);
4594 sha_mpint(&ssh->exhash, s->e);
4595 sha_mpint(&ssh->exhash, s->f);
4596 sha_mpint(&ssh->exhash, s->K);
4597 SHA_Final(&ssh->exhash, s->exchange_hash);
4599 dh_cleanup(ssh->kex_ctx);
4600 ssh->kex_ctx = NULL;
4603 debug(("Exchange hash is:\n"));
4604 dmemdump(s->exchange_hash, 20);
4607 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
4609 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
4610 (char *)s->exchange_hash, 20)) {
4611 bombout(("Server's host key did not match the signature supplied"));
4616 * Authenticate remote host: verify host key. (We've already
4617 * checked the signature of the exchange hash.)
4619 s->keystr = ssh->hostkey->fmtkey(s->hkey);
4620 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
4621 verify_ssh_host_key(ssh->frontend,
4622 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
4623 s->keystr, s->fingerprint);
4624 if (s->first_kex) { /* don't bother logging this in rekeys */
4625 logevent("Host key fingerprint is:");
4626 logevent(s->fingerprint);
4628 sfree(s->fingerprint);
4630 ssh->hostkey->freekey(s->hkey);
4633 * Send SSH2_MSG_NEWKEYS.
4635 s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
4636 ssh2_pkt_send_noqueue(ssh, s->pktout);
4639 * Now our end of the key exchange is complete, we can send all
4640 * our queued higher-layer packets.
4642 ssh->queueing = FALSE;
4643 ssh2_pkt_queuesend(ssh);
4646 * Expect SSH2_MSG_NEWKEYS from server.
4649 if (pktin->type != SSH2_MSG_NEWKEYS) {
4650 bombout(("expected new-keys packet from server"));
4655 * Create and initialise session keys.
4657 if (ssh->cs_cipher_ctx)
4658 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
4659 ssh->cscipher = s->cscipher_tobe;
4660 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
4662 if (ssh->sc_cipher_ctx)
4663 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
4664 ssh->sccipher = s->sccipher_tobe;
4665 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
4667 if (ssh->cs_mac_ctx)
4668 ssh->csmac->free_context(ssh->cs_mac_ctx);
4669 ssh->csmac = s->csmac_tobe;
4670 ssh->cs_mac_ctx = ssh->csmac->make_context();
4672 if (ssh->sc_mac_ctx)
4673 ssh->scmac->free_context(ssh->sc_mac_ctx);
4674 ssh->scmac = s->scmac_tobe;
4675 ssh->sc_mac_ctx = ssh->scmac->make_context();
4677 if (ssh->cs_comp_ctx)
4678 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
4679 ssh->cscomp = s->cscomp_tobe;
4680 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
4682 if (ssh->sc_comp_ctx)
4683 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
4684 ssh->sccomp = s->sccomp_tobe;
4685 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
4688 * Set IVs after keys. Here we use the exchange hash from the
4689 * _first_ key exchange.
4692 unsigned char keyspace[40];
4694 memcpy(ssh->v2_session_id, s->exchange_hash,
4695 sizeof(s->exchange_hash));
4696 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
4697 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
4698 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
4699 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
4700 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
4701 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
4702 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
4703 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
4704 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
4705 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
4706 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
4707 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
4709 logeventf(ssh, "Initialised %.200s client->server encryption",
4710 ssh->cscipher->text_name);
4711 logeventf(ssh, "Initialised %.200s server->client encryption",
4712 ssh->sccipher->text_name);
4713 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
4714 ssh->csmac->text_name);
4715 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
4716 ssh->scmac->text_name);
4717 if (ssh->cscomp->text_name)
4718 logeventf(ssh, "Initialised %s compression",
4719 ssh->cscomp->text_name);
4720 if (ssh->sccomp->text_name)
4721 logeventf(ssh, "Initialised %s decompression",
4722 ssh->sccomp->text_name);
4725 if (ssh->kex == &ssh_diffiehellman_gex) {
4731 * If this is the first key exchange phase, we must pass the
4732 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4733 * wants to see it but because it will need time to initialise
4734 * itself before it sees an actual packet. In subsequent key
4735 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4736 * it would only confuse the layer above.
4738 if (!s->first_kex) {
4744 * Now we're encrypting. Begin returning 1 to the protocol main
4745 * function so that other things can run on top of the
4746 * transport. If we ever see a KEXINIT, we must go back to the
4749 while (!(pktin && pktin->type == SSH2_MSG_KEXINIT)) {
4752 logevent("Server initiated key re-exchange");
4753 goto begin_key_exchange;
4759 * Add data to an SSH2 channel output buffer.
4761 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
4764 bufchain_add(&c->v.v2.outbuffer, buf, len);
4768 * Attempt to send data on an SSH2 channel.
4770 static int ssh2_try_send(struct ssh_channel *c)
4773 struct Packet *pktout;
4775 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
4778 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
4779 if ((unsigned)len > c->v.v2.remwindow)
4780 len = c->v.v2.remwindow;
4781 if ((unsigned)len > c->v.v2.remmaxpkt)
4782 len = c->v.v2.remmaxpkt;
4783 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
4784 ssh2_pkt_adduint32(pktout, c->remoteid);
4785 dont_log_data(ssh, pktout, PKTLOG_OMIT);
4786 ssh2_pkt_addstring_start(pktout);
4787 ssh2_pkt_addstring_data(pktout, data, len);
4788 end_log_omission(ssh, pktout);
4789 ssh2_pkt_send(ssh, pktout);
4790 bufchain_consume(&c->v.v2.outbuffer, len);
4791 c->v.v2.remwindow -= len;
4795 * After having sent as much data as we can, return the amount
4798 return bufchain_size(&c->v.v2.outbuffer);
4802 * Potentially enlarge the window on an SSH2 channel.
4804 static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
4809 * Never send WINDOW_ADJUST for a channel that the remote side
4810 * already thinks it's closed; there's no point, since it won't
4811 * be sending any more data anyway.
4816 if (newwin > c->v.v2.locwindow) {
4817 struct Packet *pktout;
4819 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4820 ssh2_pkt_adduint32(pktout, c->remoteid);
4821 ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
4822 ssh2_pkt_send(ssh, pktout);
4823 c->v.v2.locwindow = newwin;
4827 void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
4829 unsigned i = ssh_pkt_getuint32(pktin);
4830 struct ssh_channel *c;
4831 c = find234(ssh->channels, &i, ssh_channelfind);
4832 if (c && !c->closes)
4833 c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
4837 * Handle the SSH2 userauth and connection layers.
4839 static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
4840 struct Packet *pktin)
4842 struct do_ssh2_authconn_state {
4844 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
4846 AUTH_KEYBOARD_INTERACTIVE
4850 AUTH_TYPE_PUBLICKEY,
4851 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
4852 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
4854 AUTH_TYPE_KEYBOARD_INTERACTIVE,
4855 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4857 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
4858 int tried_pubkey_config, tried_agent, tried_keyb_inter;
4859 int kbd_inter_running;
4861 int num_prompts, curr_prompt, echo;
4866 void *publickey_blob;
4867 int publickey_bloblen;
4868 unsigned char request[5], *response, *p;
4872 char *pkblob, *alg, *commentp;
4873 int pklen, alglen, commentlen;
4874 int siglen, retlen, len;
4875 char *q, *agentreq, *ret;
4877 int num_env, env_left, env_ok;
4878 struct Packet *pktout;
4880 crState(do_ssh2_authconn_state);
4882 crBegin(ssh->do_ssh2_authconn_crstate);
4885 * Request userauth protocol, and await a response to it.
4887 s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
4888 ssh2_pkt_addstring(s->pktout, "ssh-userauth");
4889 ssh2_pkt_send(ssh, s->pktout);
4890 crWaitUntilV(pktin);
4891 if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
4892 bombout(("Server refused user authentication protocol"));
4897 * We repeat this whole loop, including the username prompt,
4898 * until we manage a successful authentication. If the user
4899 * types the wrong _password_, they can be sent back to the
4900 * beginning to try another username, if this is configured on.
4901 * (If they specify a username in the config, they are never
4902 * asked, even if they do give a wrong password.)
4904 * I think this best serves the needs of
4906 * - the people who have no configuration, no keys, and just
4907 * want to try repeated (username,password) pairs until they
4908 * type both correctly
4910 * - people who have keys and configuration but occasionally
4911 * need to fall back to passwords
4913 * - people with a key held in Pageant, who might not have
4914 * logged in to a particular machine before; so they want to
4915 * type a username, and then _either_ their key will be
4916 * accepted, _or_ they will type a password. If they mistype
4917 * the username they will want to be able to get back and
4920 s->username[0] = '\0';
4921 s->got_username = FALSE;
4926 if (s->got_username && !ssh->cfg.change_username) {
4928 * We got a username last time round this loop, and
4929 * with change_username turned off we don't try to get
4932 } else if (!*ssh->cfg.username) {
4933 if (ssh_get_line && !ssh_getline_pw_only) {
4934 if (!ssh_get_line("login as: ",
4935 s->username, sizeof(s->username), FALSE)) {
4937 * get_line failed to get a username.
4940 logevent("No username provided. Abandoning session.");
4941 ssh_closing((Plug)ssh, NULL, 0, 0);
4945 int ret; /* need not be saved across crReturn */
4946 c_write_str(ssh, "login as: ");
4948 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
4950 crWaitUntilV(!pktin);
4951 ret = process_userpass_input(ssh, in, inlen);
4955 c_write_str(ssh, "\r\n");
4957 s->username[strcspn(s->username, "\n\r")] = '\0';
4960 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
4961 s->username[sizeof(s->username)-1] = '\0';
4962 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
4963 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
4964 c_write_str(ssh, stuff);
4968 s->got_username = TRUE;
4971 * Send an authentication request using method "none": (a)
4972 * just in case it succeeds, and (b) so that we know what
4973 * authentication methods we can usefully try next.
4975 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4977 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4978 ssh2_pkt_addstring(s->pktout, s->username);
4979 ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
4980 ssh2_pkt_addstring(s->pktout, "none"); /* method */
4981 ssh2_pkt_send(ssh, s->pktout);
4982 s->type = AUTH_TYPE_NONE;
4984 s->we_are_in = FALSE;
4986 s->tried_pubkey_config = FALSE;
4987 s->tried_agent = FALSE;
4988 s->tried_keyb_inter = FALSE;
4989 s->kbd_inter_running = FALSE;
4990 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
4991 if (!filename_is_null(ssh->cfg.keyfile)) {
4993 logeventf(ssh, "Reading private key file \"%.150s\"",
4994 filename_to_str(&ssh->cfg.keyfile));
4995 keytype = key_type(&ssh->cfg.keyfile);
4996 if (keytype == SSH_KEYTYPE_SSH2) {
4998 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
4999 &s->publickey_bloblen, NULL);
5002 logeventf(ssh, "Unable to use this key file (%s)",
5003 key_type_to_str(keytype));
5004 msgbuf = dupprintf("Unable to use key file \"%.150s\""
5006 filename_to_str(&ssh->cfg.keyfile),
5007 key_type_to_str(keytype));
5008 c_write_str(ssh, msgbuf);
5010 s->publickey_blob = NULL;
5013 s->publickey_blob = NULL;
5017 * Wait for the result of the last authentication request.
5020 crWaitUntilV(pktin);
5021 while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
5025 * Don't show the banner if we're operating in
5026 * non-verbose non-interactive mode. (It's probably
5027 * a script, which means nobody will read the
5028 * banner _anyway_, and moreover the printing of
5029 * the banner will screw up processing on the
5030 * output of (say) plink.)
5032 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
5033 ssh_pkt_getstring(pktin, &banner, &size);
5035 c_write_untrusted(ssh, banner, size);
5037 crWaitUntilV(pktin);
5039 if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
5040 logevent("Access granted");
5041 s->we_are_in = TRUE;
5045 if (s->kbd_inter_running &&
5046 pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
5048 * This is either a further set-of-prompts packet
5049 * in keyboard-interactive authentication, or it's
5050 * the same one and we came back here with `gotit'
5051 * set. In the former case, we must reset the
5052 * curr_prompt variable.
5056 } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
5057 bombout(("Strange packet received during authentication: type %d",
5065 * OK, we're now sitting on a USERAUTH_FAILURE message, so
5066 * we can look at the string in it and know what we can
5067 * helpfully try next.
5069 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
5072 ssh_pkt_getstring(pktin, &methods, &methlen);
5073 s->kbd_inter_running = FALSE;
5074 if (!ssh2_pkt_getbool(pktin)) {
5076 * We have received an unequivocal Access
5077 * Denied. This can translate to a variety of
5080 * - if we'd just tried "none" authentication,
5081 * it's not worth printing anything at all
5083 * - if we'd just tried a public key _offer_,
5084 * the message should be "Server refused our
5085 * key" (or no message at all if the key
5086 * came from Pageant)
5088 * - if we'd just tried anything else, the
5089 * message really should be "Access denied".
5091 * Additionally, if we'd just tried password
5092 * authentication, we should break out of this
5093 * whole loop so as to go back to the username
5094 * prompt (iff we're configured to allow
5095 * username change attempts).
5097 if (s->type == AUTH_TYPE_NONE) {
5099 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
5100 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
5101 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
5102 c_write_str(ssh, "Server refused our key\r\n");
5103 logevent("Server refused public key");
5104 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
5105 /* server declined keyboard-interactive; ignore */
5107 c_write_str(ssh, "Access denied\r\n");
5108 logevent("Access denied");
5109 if (s->type == AUTH_TYPE_PASSWORD &&
5110 ssh->cfg.change_username) {
5111 /* XXX perhaps we should allow
5112 * keyboard-interactive to do this too? */
5113 s->we_are_in = FALSE;
5118 c_write_str(ssh, "Further authentication required\r\n");
5119 logevent("Further authentication required");
5123 in_commasep_string("publickey", methods, methlen);
5125 in_commasep_string("password", methods, methlen);
5126 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
5127 in_commasep_string("keyboard-interactive", methods, methlen);
5131 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5135 * Most password/passphrase prompts will be
5136 * non-echoing, so we set this to 0 by default.
5137 * Exception is that some keyboard-interactive prompts
5138 * can be echoing, in which case we'll set this to 1.
5142 if (!s->method && s->can_pubkey &&
5143 agent_exists() && !s->tried_agent) {
5145 * Attempt public-key authentication using Pageant.
5150 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5151 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
5153 s->tried_agent = TRUE;
5155 logevent("Pageant is running. Requesting keys.");
5157 /* Request the keys held by the agent. */
5158 PUT_32BIT(s->request, 1);
5159 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
5160 if (!agent_query(s->request, 5, &r, &s->responselen,
5161 ssh_agent_callback, ssh)) {
5165 bombout(("Unexpected data from server while"
5166 " waiting for agent response"));
5169 } while (pktin || inlen > 0);
5170 r = ssh->agent_response;
5171 s->responselen = ssh->agent_response_len;
5173 s->response = (unsigned char *) r;
5174 if (s->response && s->responselen >= 5 &&
5175 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
5176 s->p = s->response + 5;
5177 s->nkeys = GET_32BIT(s->p);
5181 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
5184 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
5189 sprintf(buf, "Trying Pageant key #%d", s->keyi);
5192 s->pklen = GET_32BIT(s->p);
5194 if (s->publickey_blob &&
5195 s->pklen == s->publickey_bloblen &&
5196 !memcmp(s->p, s->publickey_blob,
5197 s->publickey_bloblen)) {
5198 logevent("This key matches configured key file");
5199 s->tried_pubkey_config = 1;
5201 s->pkblob = (char *)s->p;
5203 s->alglen = GET_32BIT(s->pkblob);
5204 s->alg = s->pkblob + 4;
5205 s->commentlen = GET_32BIT(s->p);
5207 s->commentp = (char *)s->p;
5208 s->p += s->commentlen;
5209 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
5210 ssh2_pkt_addstring(s->pktout, s->username);
5211 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
5212 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
5213 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
5214 ssh2_pkt_addstring_start(s->pktout);
5215 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
5216 ssh2_pkt_addstring_start(s->pktout);
5217 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
5218 ssh2_pkt_send(ssh, s->pktout);
5220 crWaitUntilV(pktin);
5221 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
5222 logevent("Key refused");
5226 if (flags & FLAG_VERBOSE) {
5227 c_write_str(ssh, "Authenticating with "
5229 c_write(ssh, s->commentp, s->commentlen);
5230 c_write_str(ssh, "\" from agent\r\n");
5234 * Server is willing to accept the key.
5235 * Construct a SIGN_REQUEST.
5237 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
5238 ssh2_pkt_addstring(s->pktout, s->username);
5239 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
5240 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
5241 ssh2_pkt_addbool(s->pktout, TRUE);
5242 ssh2_pkt_addstring_start(s->pktout);
5243 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
5244 ssh2_pkt_addstring_start(s->pktout);
5245 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
5247 s->siglen = s->pktout->length - 5 + 4 + 20;
5248 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
5250 s->len = 1; /* message type */
5251 s->len += 4 + s->pklen; /* key blob */
5252 s->len += 4 + s->siglen; /* data to sign */
5253 s->len += 4; /* flags */
5254 s->agentreq = snewn(4 + s->len, char);
5255 PUT_32BIT(s->agentreq, s->len);
5256 s->q = s->agentreq + 4;
5257 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
5258 PUT_32BIT(s->q, s->pklen);
5260 memcpy(s->q, s->pkblob, s->pklen);
5262 PUT_32BIT(s->q, s->siglen);
5264 /* Now the data to be signed... */
5265 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5266 PUT_32BIT(s->q, 20);
5269 memcpy(s->q, ssh->v2_session_id, 20);
5271 memcpy(s->q, s->pktout->data + 5,
5272 s->pktout->length - 5);
5273 s->q += s->pktout->length - 5;
5274 /* And finally the (zero) flags word. */
5276 if (!agent_query(s->agentreq, s->len + 4,
5278 ssh_agent_callback, ssh)) {
5282 bombout(("Unexpected data from server"
5283 " while waiting for agent"
5287 } while (pktin || inlen > 0);
5288 vret = ssh->agent_response;
5289 s->retlen = ssh->agent_response_len;
5294 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
5295 logevent("Sending Pageant's response");
5296 ssh2_add_sigblob(ssh, s->pktout,
5297 s->pkblob, s->pklen,
5299 GET_32BIT(s->ret + 5));
5300 ssh2_pkt_send(ssh, s->pktout);
5305 ("Pageant failed to answer challenge");
5316 if (!s->method && s->can_pubkey && s->publickey_blob
5317 && !s->tried_pubkey_config) {
5318 unsigned char *pub_blob;
5319 char *algorithm, *comment;
5322 s->tried_pubkey_config = TRUE;
5324 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5325 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
5328 * Try the public key supplied in the configuration.
5330 * First, offer the public blob to see if the server is
5331 * willing to accept it.
5334 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
5339 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
5340 ssh2_pkt_addstring(s->pktout, s->username);
5341 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
5342 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
5343 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
5344 ssh2_pkt_addstring(s->pktout, algorithm);
5345 ssh2_pkt_addstring_start(s->pktout);
5346 ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
5348 ssh2_pkt_send(ssh, s->pktout);
5349 logevent("Offered public key");
5351 crWaitUntilV(pktin);
5352 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
5354 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
5355 continue; /* key refused; give up on it */
5358 logevent("Offer of public key accepted");
5360 * Actually attempt a serious authentication using
5363 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
5364 sprintf(s->pwprompt,
5365 "Passphrase for key \"%.100s\": ",
5371 if (flags & FLAG_VERBOSE) {
5372 c_write_str(ssh, "Authenticating with public key \"");
5373 c_write_str(ssh, comment);
5374 c_write_str(ssh, "\"\r\n");
5376 s->method = AUTH_PUBLICKEY_FILE;
5380 if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
5381 s->method = AUTH_KEYBOARD_INTERACTIVE;
5382 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
5383 s->tried_keyb_inter = TRUE;
5385 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5386 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
5388 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
5389 ssh2_pkt_addstring(s->pktout, s->username);
5390 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
5391 ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
5392 ssh2_pkt_addstring(s->pktout, ""); /* lang */
5393 ssh2_pkt_addstring(s->pktout, "");
5394 ssh2_pkt_send(ssh, s->pktout);
5396 crWaitUntilV(pktin);
5397 if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
5398 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
5400 logevent("Keyboard-interactive authentication refused");
5401 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
5405 s->kbd_inter_running = TRUE;
5409 if (s->kbd_inter_running) {
5410 s->method = AUTH_KEYBOARD_INTERACTIVE;
5411 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
5412 s->tried_keyb_inter = TRUE;
5414 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5415 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
5417 if (s->curr_prompt == 0) {
5419 * We've got a fresh USERAUTH_INFO_REQUEST.
5420 * Display header data, and start going through
5423 char *name, *inst, *lang;
5424 int name_len, inst_len, lang_len;
5426 ssh_pkt_getstring(pktin, &name, &name_len);
5427 ssh_pkt_getstring(pktin, &inst, &inst_len);
5428 ssh_pkt_getstring(pktin, &lang, &lang_len);
5430 c_write_untrusted(ssh, name, name_len);
5431 c_write_str(ssh, "\r\n");
5434 c_write_untrusted(ssh, inst, inst_len);
5435 c_write_str(ssh, "\r\n");
5437 s->num_prompts = ssh_pkt_getuint32(pktin);
5441 * If there are prompts remaining in the packet,
5442 * display one and get a response.
5444 if (s->curr_prompt < s->num_prompts) {
5448 ssh_pkt_getstring(pktin, &prompt, &prompt_len);
5449 if (prompt_len > 0) {
5450 static const char trunc[] = "<prompt truncated>: ";
5451 static const int prlen = sizeof(s->pwprompt) -
5453 if (prompt_len > prlen) {
5454 memcpy(s->pwprompt, prompt, prlen);
5455 strcpy(s->pwprompt + prlen, trunc);
5457 memcpy(s->pwprompt, prompt, prompt_len);
5458 s->pwprompt[prompt_len] = '\0';
5462 "<server failed to send prompt>: ");
5464 s->echo = ssh2_pkt_getbool(pktin);
5470 if (!s->method && s->can_passwd) {
5471 s->method = AUTH_PASSWORD;
5472 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5473 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
5474 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
5481 if (!ssh_get_line(s->pwprompt, s->password,
5482 sizeof(s->password), TRUE)) {
5484 * get_line failed to get a password (for
5485 * example because one was supplied on the
5486 * command line which has already failed to
5489 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5490 ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
5491 ssh2_pkt_addstring(s->pktout, "No more passwords available"
5493 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5494 ssh2_pkt_send_noqueue(ssh, s->pktout);
5495 logevent("Unable to authenticate");
5496 connection_fatal(ssh->frontend,
5497 "Unable to authenticate");
5498 ssh_closing((Plug)ssh, NULL, 0, 0);
5502 int ret; /* need not be saved across crReturn */
5503 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
5506 setup_userpass_input(ssh, s->password,
5507 sizeof(s->password), s->echo);
5509 crWaitUntilV(!pktin);
5510 ret = process_userpass_input(ssh, in, inlen);
5514 c_write_str(ssh, "\r\n");
5518 if (s->method == AUTH_PUBLICKEY_FILE) {
5520 * We have our passphrase. Now try the actual authentication.
5522 struct ssh2_userkey *key;
5523 const char *error = NULL;
5525 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
5527 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
5528 if (key == SSH2_WRONG_PASSPHRASE) {
5529 c_write_str(ssh, "Wrong passphrase\r\n");
5530 s->tried_pubkey_config = FALSE;
5532 c_write_str(ssh, "Unable to load private key (");
5533 c_write_str(ssh, error);
5534 c_write_str(ssh, ")\r\n");
5535 s->tried_pubkey_config = TRUE;
5537 /* Send a spurious AUTH_NONE to return to the top. */
5538 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
5539 ssh2_pkt_addstring(s->pktout, s->username);
5540 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
5541 ssh2_pkt_addstring(s->pktout, "none"); /* method */
5542 ssh2_pkt_send(ssh, s->pktout);
5543 s->type = AUTH_TYPE_NONE;
5545 unsigned char *pkblob, *sigblob, *sigdata;
5546 int pkblob_len, sigblob_len, sigdata_len;
5550 * We have loaded the private key and the server
5551 * has announced that it's willing to accept it.
5552 * Hallelujah. Generate a signature and send it.
5554 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
5555 ssh2_pkt_addstring(s->pktout, s->username);
5556 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
5557 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
5558 ssh2_pkt_addbool(s->pktout, TRUE);
5559 ssh2_pkt_addstring(s->pktout, key->alg->name);
5560 pkblob = key->alg->public_blob(key->data, &pkblob_len);
5561 ssh2_pkt_addstring_start(s->pktout);
5562 ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
5565 * The data to be signed is:
5569 * followed by everything so far placed in the
5572 sigdata_len = s->pktout->length - 5 + 4 + 20;
5573 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
5575 sigdata = snewn(sigdata_len, unsigned char);
5577 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5578 PUT_32BIT(sigdata+p, 20);
5581 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
5582 memcpy(sigdata+p, s->pktout->data + 5,
5583 s->pktout->length - 5);
5584 p += s->pktout->length - 5;
5585 assert(p == sigdata_len);
5586 sigblob = key->alg->sign(key->data, (char *)sigdata,
5587 sigdata_len, &sigblob_len);
5588 ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
5589 sigblob, sigblob_len);
5594 ssh2_pkt_send(ssh, s->pktout);
5595 s->type = AUTH_TYPE_PUBLICKEY;
5596 key->alg->freekey(key->data);
5598 } else if (s->method == AUTH_PASSWORD) {
5600 * We send the password packet lumped tightly together with
5601 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5602 * string long enough to make the total length of the two
5603 * packets constant. This should ensure that a passive
5604 * listener doing traffic analyis can't work out the length
5607 * For this to work, we need an assumption about the
5608 * maximum length of the password packet. I think 256 is
5609 * pretty conservative. Anyone using a password longer than
5610 * that probably doesn't have much to worry about from
5611 * people who find out how long their password is!
5613 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
5614 ssh2_pkt_addstring(s->pktout, s->username);
5615 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
5616 ssh2_pkt_addstring(s->pktout, "password");
5617 ssh2_pkt_addbool(s->pktout, FALSE);
5618 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
5619 ssh2_pkt_addstring(s->pktout, s->password);
5620 memset(s->password, 0, sizeof(s->password));
5621 end_log_omission(ssh, s->pktout);
5622 ssh2_pkt_defer(ssh, s->pktout);
5624 * We'll include a string that's an exact multiple of the
5625 * cipher block size. If the cipher is NULL for some
5626 * reason, we don't do this trick at all because we gain
5629 if (ssh->cscipher) {
5632 stringlen = (256 - ssh->deferred_len);
5633 stringlen += ssh->cscipher->blksize - 1;
5634 stringlen -= (stringlen % ssh->cscipher->blksize);
5637 * Temporarily disable actual compression,
5638 * so we can guarantee to get this string
5639 * exactly the length we want it. The
5640 * compression-disabling routine should
5641 * return an integer indicating how many
5642 * bytes we should adjust our string length
5646 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
5648 s->pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
5649 ssh2_pkt_addstring_start(s->pktout);
5650 for (i = 0; i < stringlen; i++) {
5651 char c = (char) random_byte();
5652 ssh2_pkt_addstring_data(s->pktout, &c, 1);
5654 ssh2_pkt_defer(ssh, s->pktout);
5656 ssh_pkt_defersend(ssh);
5657 logevent("Sent password");
5658 s->type = AUTH_TYPE_PASSWORD;
5659 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
5660 if (s->curr_prompt == 0) {
5661 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
5662 ssh2_pkt_adduint32(s->pktout, s->num_prompts);
5664 if (s->need_pw) { /* only add pw if we just got one! */
5665 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
5666 ssh2_pkt_addstring(s->pktout, s->password);
5667 memset(s->password, 0, sizeof(s->password));
5668 end_log_omission(ssh, s->pktout);
5671 if (s->curr_prompt >= s->num_prompts) {
5672 ssh2_pkt_send(ssh, s->pktout);
5675 * If there are prompts remaining, we set
5676 * `gotit' so that we won't attempt to get
5677 * another packet. Then we go back round the
5678 * loop and will end up retrieving another
5679 * prompt out of the existing packet. Funky or
5684 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
5686 c_write_str(ssh, "No supported authentication methods"
5687 " left to try!\r\n");
5688 logevent("No supported authentications offered."
5690 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5691 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
5692 ssh2_pkt_addstring(s->pktout, "No supported authentication"
5693 " methods available");
5694 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5695 ssh2_pkt_send_noqueue(ssh, s->pktout);
5696 ssh_closing((Plug)ssh, NULL, 0, 0);
5700 } while (!s->we_are_in);
5703 * Now we're authenticated for the connection protocol. The
5704 * connection protocol will automatically have started at this
5705 * point; there's no need to send SERVICE_REQUEST.
5708 ssh->channels = newtree234(ssh_channelcmp);
5711 * Set up handlers for some connection protocol messages, so we
5712 * don't have to handle them repeatedly in this coroutine.
5714 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
5715 ssh2_msg_channel_window_adjust;
5718 * Create the main session channel.
5720 if (!ssh->cfg.ssh_no_shell) {
5721 ssh->mainchan = snew(struct ssh_channel);
5722 ssh->mainchan->ssh = ssh;
5723 ssh->mainchan->localid = alloc_channel_id(ssh);
5724 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
5725 ssh2_pkt_addstring(s->pktout, "session");
5726 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
5727 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
5728 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
5729 ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
5730 ssh2_pkt_send(ssh, s->pktout);
5731 crWaitUntilV(pktin);
5732 if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
5733 bombout(("Server refused to open a session"));
5735 /* FIXME: error data comes back in FAILURE packet */
5737 if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
5738 bombout(("Server's channel confirmation cited wrong channel"));
5741 ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
5742 ssh->mainchan->type = CHAN_MAINSESSION;
5743 ssh->mainchan->closes = 0;
5744 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
5745 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
5746 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
5747 add234(ssh->channels, ssh->mainchan);
5748 update_specials_menu(ssh->frontend);
5749 logevent("Opened channel for session");
5751 ssh->mainchan = NULL;
5754 * Potentially enable X11 forwarding.
5756 if (ssh->mainchan && ssh->cfg.x11_forward) {
5757 char proto[20], data[64];
5758 logevent("Requesting X11 forwarding");
5759 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
5760 data, sizeof(data), ssh->cfg.x11_auth);
5761 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
5762 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
5763 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
5764 ssh2_pkt_addstring(s->pktout, "x11-req");
5765 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
5766 ssh2_pkt_addbool(s->pktout, 0); /* many connections */
5767 ssh2_pkt_addstring(s->pktout, proto);
5768 ssh2_pkt_addstring(s->pktout, data);
5769 ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
5770 ssh2_pkt_send(ssh, s->pktout);
5772 crWaitUntilV(pktin);
5774 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
5775 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
5776 bombout(("Unexpected response to X11 forwarding request:"
5777 " packet type %d", pktin->type));
5780 logevent("X11 forwarding refused");
5782 logevent("X11 forwarding enabled");
5783 ssh->X11_fwd_enabled = TRUE;
5788 * Enable port forwardings.
5793 int sport,dport,sserv,dserv;
5794 char sports[256], dports[256], saddr[256], host[256];
5796 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
5797 /* Add port forwardings. */
5798 ssh->portfwd_strptr = ssh->cfg.portfwd;
5799 while (*ssh->portfwd_strptr) {
5800 type = *ssh->portfwd_strptr++;
5803 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
5804 if (*ssh->portfwd_strptr == ':') {
5806 * We've seen a colon in the middle of the
5807 * source port number. This means that
5808 * everything we've seen until now is the
5809 * source _address_, so we'll move it into
5810 * saddr and start sports from the beginning
5813 ssh->portfwd_strptr++;
5815 strcpy(saddr, sports);
5818 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
5822 if (*ssh->portfwd_strptr == '\t')
5823 ssh->portfwd_strptr++;
5825 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
5826 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
5829 if (*ssh->portfwd_strptr == ':')
5830 ssh->portfwd_strptr++;
5832 while (*ssh->portfwd_strptr) {
5833 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
5836 ssh->portfwd_strptr++;
5837 dport = atoi(dports);
5841 dport = net_service_lookup(dports);
5843 logeventf(ssh, "Service lookup failed for destination"
5844 " port \"%s\"", dports);
5848 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
5850 ssh->portfwd_strptr++; /* eat the NUL and move to next one */
5852 sport = atoi(sports);
5856 sport = net_service_lookup(sports);
5858 logeventf(ssh, "Service lookup failed for source"
5859 " port \"%s\"", sports);
5862 if (sport && dport) {
5863 /* Set up a description of the source port. */
5864 static char *sportdesc;
5865 sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
5866 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5867 (int)(*saddr?1:0), ":",
5868 (int)(sserv ? strlen(sports) : 0), sports,
5869 sserv, "(", sport, sserv, ")");
5871 /* Verbose description of the destination port */
5872 char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
5874 (int)(dserv ? strlen(dports) : 0), dports,
5875 dserv, "(", dport, dserv, ")");
5876 const char *err = pfd_addforward(host, dport,
5877 *saddr ? saddr : NULL,
5878 sport, ssh, &ssh->cfg);
5880 logeventf(ssh, "Local port %s forward to %s"
5881 " failed: %s", sportdesc, dportdesc, err);
5883 logeventf(ssh, "Local port %s forwarding to %s",
5884 sportdesc, dportdesc);
5887 } else if (type == 'D') {
5888 const char *err = pfd_addforward(NULL, -1,
5889 *saddr ? saddr : NULL,
5890 sport, ssh, &ssh->cfg);
5892 logeventf(ssh, "Local port %s SOCKS dynamic forward"
5893 " setup failed: %s", sportdesc, err);
5895 logeventf(ssh, "Local port %s doing SOCKS"
5896 " dynamic forwarding", sportdesc);
5899 struct ssh_rportfwd *pf;
5900 pf = snew(struct ssh_rportfwd);
5901 strcpy(pf->dhost, host);
5904 if (add234(ssh->rportfwds, pf) != pf) {
5905 logeventf(ssh, "Duplicate remote port forwarding"
5906 " to %s:%d", host, dport);
5909 logeventf(ssh, "Requesting remote port %s"
5910 " forward to %s:%.*s%.*s%d%.*s",
5913 (int)(dserv ? strlen(dports) : 0), dports,
5914 dserv, "(", dport, dserv, ")");
5915 s->pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
5916 ssh2_pkt_addstring(s->pktout, "tcpip-forward");
5917 ssh2_pkt_addbool(s->pktout, 1);/* want reply */
5919 ssh2_pkt_addstring(s->pktout, saddr);
5920 } else if (ssh->cfg.rport_acceptall) {
5921 ssh2_pkt_addstring(s->pktout, "0.0.0.0");
5923 ssh2_pkt_addstring(s->pktout, "127.0.0.1");
5925 ssh2_pkt_adduint32(s->pktout, sport);
5926 ssh2_pkt_send(ssh, s->pktout);
5928 crWaitUntilV(pktin);
5930 if (pktin->type != SSH2_MSG_REQUEST_SUCCESS) {
5931 if (pktin->type != SSH2_MSG_REQUEST_FAILURE) {
5932 bombout(("Unexpected response to port "
5933 "forwarding request: packet type %d",
5937 logevent("Server refused this port forwarding");
5939 logevent("Remote port forwarding enabled");
5949 * Potentially enable agent forwarding.
5951 if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
5952 logevent("Requesting OpenSSH-style agent forwarding");
5953 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
5954 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
5955 ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com");
5956 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
5957 ssh2_pkt_send(ssh, s->pktout);
5959 crWaitUntilV(pktin);
5961 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
5962 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
5963 bombout(("Unexpected response to agent forwarding request:"
5964 " packet type %d", pktin->type));
5967 logevent("Agent forwarding refused");
5969 logevent("Agent forwarding enabled");
5970 ssh->agentfwd_enabled = TRUE;
5975 * Now allocate a pty for the session.
5977 if (ssh->mainchan && !ssh->cfg.nopty) {
5978 /* Unpick the terminal-speed string. */
5979 /* XXX perhaps we should allow no speeds to be sent. */
5980 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
5981 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
5982 /* Build the pty request. */
5983 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
5984 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
5985 ssh2_pkt_addstring(s->pktout, "pty-req");
5986 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
5987 ssh2_pkt_addstring(s->pktout, ssh->cfg.termtype);
5988 ssh2_pkt_adduint32(s->pktout, ssh->term_width);
5989 ssh2_pkt_adduint32(s->pktout, ssh->term_height);
5990 ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
5991 ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
5992 ssh2_pkt_addstring_start(s->pktout);
5993 ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
5994 ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
5995 ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
5996 ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
5997 ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
5998 ssh2_pkt_send(ssh, s->pktout);
5999 ssh->state = SSH_STATE_INTERMED;
6001 crWaitUntilV(pktin);
6003 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6004 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6005 bombout(("Unexpected response to pty request:"
6006 " packet type %d", pktin->type));
6009 c_write_str(ssh, "Server refused to allocate pty\r\n");
6010 ssh->editing = ssh->echoing = 1;
6012 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6013 ssh->ospeed, ssh->ispeed);
6016 ssh->editing = ssh->echoing = 1;
6020 * Send environment variables.
6022 * Simplest thing here is to send all the requests at once, and
6023 * then wait for a whole bunch of successes or failures.
6025 if (ssh->mainchan && *ssh->cfg.environmt) {
6026 char *e = ssh->cfg.environmt;
6027 char *var, *varend, *val;
6033 while (*e && *e != '\t') e++;
6035 if (*e == '\t') e++;
6040 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6041 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6042 ssh2_pkt_addstring(s->pktout, "env");
6043 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6044 ssh2_pkt_addstring_start(s->pktout);
6045 ssh2_pkt_addstring_data(s->pktout, var, varend-var);
6046 ssh2_pkt_addstring(s->pktout, val);
6047 ssh2_pkt_send(ssh, s->pktout);
6052 logeventf(ssh, "Sent %d environment variables", s->num_env);
6055 s->env_left = s->num_env;
6057 while (s->env_left > 0) {
6058 crWaitUntilV(pktin);
6060 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6061 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6062 bombout(("Unexpected response to environment request:"
6063 " packet type %d", pktin->type));
6073 if (s->env_ok == s->num_env) {
6074 logevent("All environment variables successfully set");
6075 } else if (s->env_ok == 0) {
6076 logevent("All environment variables refused");
6077 c_write_str(ssh, "Server refused to set environment variables\r\n");
6079 logeventf(ssh, "%d environment variables refused",
6080 s->num_env - s->env_ok);
6081 c_write_str(ssh, "Server refused to set all environment variables\r\n");
6086 * Start a shell or a remote command. We may have to attempt
6087 * this twice if the config data has provided a second choice
6090 if (ssh->mainchan) while (1) {
6094 if (ssh->fallback_cmd) {
6095 subsys = ssh->cfg.ssh_subsys2;
6096 cmd = ssh->cfg.remote_cmd_ptr2;
6098 subsys = ssh->cfg.ssh_subsys;
6099 cmd = ssh->cfg.remote_cmd_ptr;
6102 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6103 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
6105 ssh2_pkt_addstring(s->pktout, "subsystem");
6106 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6107 ssh2_pkt_addstring(s->pktout, cmd);
6109 ssh2_pkt_addstring(s->pktout, "exec");
6110 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6111 ssh2_pkt_addstring(s->pktout, cmd);
6113 ssh2_pkt_addstring(s->pktout, "shell");
6114 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6116 ssh2_pkt_send(ssh, s->pktout);
6118 crWaitUntilV(pktin);
6120 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6121 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6122 bombout(("Unexpected response to shell/command request:"
6123 " packet type %d", pktin->type));
6127 * We failed to start the command. If this is the
6128 * fallback command, we really are finished; if it's
6129 * not, and if the fallback command exists, try falling
6130 * back to it before complaining.
6132 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
6133 logevent("Primary command failed; attempting fallback");
6134 ssh->fallback_cmd = TRUE;
6137 bombout(("Server refused to start a shell/command"));
6140 logevent("Started a shell/command");
6145 ssh->state = SSH_STATE_SESSION;
6146 if (ssh->size_needed)
6147 ssh_size(ssh, ssh->term_width, ssh->term_height);
6148 if (ssh->eof_needed)
6149 ssh_special(ssh, TS_EOF);
6155 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
6160 s->try_send = FALSE;
6162 if (pktin->type == SSH2_MSG_CHANNEL_DATA ||
6163 pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
6166 unsigned i = ssh_pkt_getuint32(pktin);
6167 struct ssh_channel *c;
6168 c = find234(ssh->channels, &i, ssh_channelfind);
6170 continue; /* nonexistent channel */
6171 if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
6172 ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
6173 continue; /* extended but not stderr */
6174 ssh_pkt_getstring(pktin, &data, &length);
6177 c->v.v2.locwindow -= length;
6179 case CHAN_MAINSESSION:
6181 from_backend(ssh->frontend, pktin->type ==
6182 SSH2_MSG_CHANNEL_EXTENDED_DATA,
6186 bufsize = x11_send(c->u.x11.s, data, length);
6189 bufsize = pfd_send(c->u.pfd.s, data, length);
6192 while (length > 0) {
6193 if (c->u.a.lensofar < 4) {
6194 int l = min(4 - c->u.a.lensofar, length);
6195 memcpy(c->u.a.msglen + c->u.a.lensofar,
6199 c->u.a.lensofar += l;
6201 if (c->u.a.lensofar == 4) {
6203 4 + GET_32BIT(c->u.a.msglen);
6204 c->u.a.message = snewn(c->u.a.totallen,
6206 memcpy(c->u.a.message, c->u.a.msglen, 4);
6208 if (c->u.a.lensofar >= 4 && length > 0) {
6210 min(c->u.a.totallen - c->u.a.lensofar,
6212 memcpy(c->u.a.message + c->u.a.lensofar,
6216 c->u.a.lensofar += l;
6218 if (c->u.a.lensofar == c->u.a.totallen) {
6221 if (agent_query(c->u.a.message,
6224 ssh_agentf_callback, c))
6225 ssh_agentf_callback(c, reply, replylen);
6226 sfree(c->u.a.message);
6227 c->u.a.lensofar = 0;
6234 * If we are not buffering too much data,
6235 * enlarge the window again at the remote side.
6237 if (bufsize < OUR_V2_WINSIZE)
6238 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
6240 } else if (pktin->type == SSH2_MSG_CHANNEL_EOF) {
6241 unsigned i = ssh_pkt_getuint32(pktin);
6242 struct ssh_channel *c;
6244 c = find234(ssh->channels, &i, ssh_channelfind);
6246 continue; /* nonexistent channel */
6248 if (c->type == CHAN_X11) {
6250 * Remote EOF on an X11 channel means we should
6251 * wrap up and close the channel ourselves.
6253 x11_close(c->u.x11.s);
6255 } else if (c->type == CHAN_AGENT) {
6257 } else if (c->type == CHAN_SOCKDATA) {
6258 pfd_close(c->u.pfd.s);
6261 } else if (pktin->type == SSH2_MSG_CHANNEL_CLOSE) {
6262 unsigned i = ssh_pkt_getuint32(pktin);
6263 struct ssh_channel *c;
6265 c = find234(ssh->channels, &i, ssh_channelfind);
6266 if (!c || ((int)c->remoteid) == -1) {
6267 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
6268 c ? "half-open" : "nonexistent", i));
6271 /* Do pre-close processing on the channel. */
6273 case CHAN_MAINSESSION:
6274 ssh->mainchan = NULL;
6275 update_specials_menu(ssh->frontend);
6278 if (c->u.x11.s != NULL)
6279 x11_close(c->u.x11.s);
6286 if (c->u.pfd.s != NULL)
6287 pfd_close(c->u.pfd.s);
6291 if (c->closes == 0) {
6292 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
6293 ssh2_pkt_adduint32(s->pktout, c->remoteid);
6294 ssh2_pkt_send(ssh, s->pktout);
6296 del234(ssh->channels, c);
6297 bufchain_clear(&c->v.v2.outbuffer);
6301 * See if that was the last channel left open.
6302 * (This is only our termination condition if we're
6303 * not running in -N mode.)
6305 if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
6306 logevent("All channels closed. Disconnecting");
6309 * We used to send SSH_MSG_DISCONNECT here,
6310 * because I'd believed that _every_ conforming
6311 * SSH2 connection had to end with a disconnect
6312 * being sent by at least one side; apparently
6313 * I was wrong and it's perfectly OK to
6314 * unceremoniously slam the connection shut
6315 * when you're done, and indeed OpenSSH feels
6316 * this is more polite than sending a
6317 * DISCONNECT. So now we don't.
6319 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6320 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
6321 ssh2_pkt_addstring(s->pktout, "All open channels closed");
6322 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
6323 ssh2_pkt_send_noqueue(ssh, s->pktout);
6325 ssh_closing((Plug)ssh, NULL, 0, 0);
6328 continue; /* remote sends close; ignore (FIXME) */
6329 } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
6330 unsigned i = ssh_pkt_getuint32(pktin);
6331 struct ssh_channel *c;
6332 c = find234(ssh->channels, &i, ssh_channelfind);
6334 continue; /* nonexistent channel */
6335 if (c->type != CHAN_SOCKDATA_DORMANT)
6336 continue; /* dunno why they're confirming this */
6337 c->remoteid = ssh_pkt_getuint32(pktin);
6338 c->type = CHAN_SOCKDATA;
6339 c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
6340 c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
6342 pfd_confirm(c->u.pfd.s);
6345 * We have a pending close on this channel,
6346 * which we decided on before the server acked
6347 * the channel open. So now we know the
6348 * remoteid, we can close it again.
6350 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
6351 ssh2_pkt_adduint32(s->pktout, c->remoteid);
6352 ssh2_pkt_send(ssh, s->pktout);
6354 } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
6355 static const char *const reasons[] = {
6356 "<unknown reason code>",
6357 "Administratively prohibited",
6359 "Unknown channel type",
6360 "Resource shortage",
6362 unsigned i = ssh_pkt_getuint32(pktin);
6363 unsigned reason_code;
6364 char *reason_string;
6367 struct ssh_channel *c;
6368 c = find234(ssh->channels, &i, ssh_channelfind);
6370 continue; /* nonexistent channel */
6371 if (c->type != CHAN_SOCKDATA_DORMANT)
6372 continue; /* dunno why they're failing this */
6374 reason_code = ssh_pkt_getuint32(pktin);
6375 if (reason_code >= lenof(reasons))
6376 reason_code = 0; /* ensure reasons[reason_code] in range */
6377 ssh_pkt_getstring(pktin, &reason_string, &reason_length);
6378 message = dupprintf("Forwarded connection refused by"
6379 " server: %s [%.*s]", reasons[reason_code],
6380 reason_length, reason_string);
6384 pfd_close(c->u.pfd.s);
6386 del234(ssh->channels, c);
6388 } else if (pktin->type == SSH2_MSG_CHANNEL_REQUEST) {
6391 int typelen, want_reply;
6392 int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
6393 struct ssh_channel *c;
6395 localid = ssh_pkt_getuint32(pktin);
6396 ssh_pkt_getstring(pktin, &type, &typelen);
6397 want_reply = ssh2_pkt_getbool(pktin);
6400 * First, check that the channel exists. Otherwise,
6401 * we can instantly disconnect with a rude message.
6403 c = find234(ssh->channels, &localid, ssh_channelfind);
6406 sprintf(buf, "Received channel request for nonexistent"
6407 " channel %d", localid);
6409 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6410 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
6411 ssh2_pkt_addstring(s->pktout, buf);
6412 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
6413 ssh2_pkt_send_noqueue(ssh, s->pktout);
6414 connection_fatal(ssh->frontend, "%s", buf);
6415 ssh_closing((Plug)ssh, NULL, 0, 0);
6420 * Having got the channel number, we now look at
6421 * the request type string to see if it's something
6424 if (c == ssh->mainchan) {
6426 * We recognise "exit-status" and "exit-signal" on
6427 * the primary channel.
6429 if (typelen == 11 &&
6430 !memcmp(type, "exit-status", 11)) {
6432 ssh->exitcode = ssh_pkt_getuint32(pktin);
6433 logeventf(ssh, "Server sent command exit status %d",
6435 reply = SSH2_MSG_CHANNEL_SUCCESS;
6437 } else if (typelen == 11 &&
6438 !memcmp(type, "exit-signal", 11)) {
6440 int is_plausible = TRUE, is_int = FALSE;
6441 char *fmt_sig = "", *fmt_msg = "";
6443 int msglen = 0, core = FALSE;
6444 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6445 * provide an `int' for the signal, despite its
6446 * having been a `string' in the drafts since at
6447 * least 2001. (Fixed in session.c 1.147.) Try to
6448 * infer which we can safely parse it as. */
6450 unsigned char *p = pktin->body +
6452 long len = pktin->length - pktin->savedpos;
6453 unsigned long num = GET_32BIT(p); /* what is it? */
6454 /* If it's 0, it hardly matters; assume string */
6458 int maybe_int = FALSE, maybe_str = FALSE;
6459 #define CHECK_HYPOTHESIS(offset, result) \
6462 if (q >= 0 && q+4 <= len) { \
6463 q = q + 4 + GET_32BIT(p+q); \
6464 if (q >= 0 && q+4 <= len && \
6465 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
6469 CHECK_HYPOTHESIS(4+1, maybe_int);
6470 CHECK_HYPOTHESIS(4+num+1, maybe_str);
6471 #undef CHECK_HYPOTHESIS
6472 if (maybe_int && !maybe_str)
6474 else if (!maybe_int && maybe_str)
6477 /* Crikey. Either or neither. Panic. */
6478 is_plausible = FALSE;
6483 /* Old non-standard OpenSSH. */
6484 int signum = ssh_pkt_getuint32(pktin);
6485 fmt_sig = dupprintf(" %d", signum);
6487 /* As per the drafts. */
6490 ssh_pkt_getstring(pktin, &sig, &siglen);
6491 /* Signal name isn't supposed to be blank, but
6492 * let's cope gracefully if it is. */
6494 fmt_sig = dupprintf(" \"%.*s\"",
6498 core = ssh2_pkt_getbool(pktin);
6499 ssh_pkt_getstring(pktin, &msg, &msglen);
6501 fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
6503 /* ignore lang tag */
6504 } /* else don't attempt to parse */
6505 logeventf(ssh, "Server exited on signal%s%s%s",
6506 fmt_sig, core ? " (core dumped)" : "",
6508 if (*fmt_sig) sfree(fmt_sig);
6509 if (*fmt_msg) sfree(fmt_msg);
6510 reply = SSH2_MSG_CHANNEL_SUCCESS;
6515 * This is a channel request we don't know
6516 * about, so we now either ignore the request
6517 * or respond with CHANNEL_FAILURE, depending
6520 reply = SSH2_MSG_CHANNEL_FAILURE;
6523 s->pktout = ssh2_pkt_init(reply);
6524 ssh2_pkt_adduint32(s->pktout, c->remoteid);
6525 ssh2_pkt_send(ssh, s->pktout);
6527 } else if (pktin->type == SSH2_MSG_GLOBAL_REQUEST) {
6529 int typelen, want_reply;
6531 ssh_pkt_getstring(pktin, &type, &typelen);
6532 want_reply = ssh2_pkt_getbool(pktin);
6535 * We currently don't support any global requests
6536 * at all, so we either ignore the request or
6537 * respond with REQUEST_FAILURE, depending on
6541 s->pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
6542 ssh2_pkt_send(ssh, s->pktout);
6544 } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN) {
6551 struct ssh_channel *c;
6552 unsigned remid, winsize, pktsize;
6553 ssh_pkt_getstring(pktin, &type, &typelen);
6554 c = snew(struct ssh_channel);
6557 remid = ssh_pkt_getuint32(pktin);
6558 winsize = ssh_pkt_getuint32(pktin);
6559 pktsize = ssh_pkt_getuint32(pktin);
6561 if (typelen == 3 && !memcmp(type, "x11", 3)) {
6564 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
6565 addrstr = snewn(peeraddrlen+1, char);
6566 memcpy(addrstr, peeraddr, peeraddrlen);
6567 addrstr[peeraddrlen] = '\0';
6568 peerport = ssh_pkt_getuint32(pktin);
6570 logeventf(ssh, "Received X11 connect request from %s:%d",
6573 if (!ssh->X11_fwd_enabled)
6574 error = "X11 forwarding is not enabled";
6575 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
6576 ssh->x11auth, addrstr, peerport,
6577 &ssh->cfg) != NULL) {
6578 error = "Unable to open an X11 connection";
6580 logevent("Opening X11 forward connection succeeded");
6585 } else if (typelen == 15 &&
6586 !memcmp(type, "forwarded-tcpip", 15)) {
6587 struct ssh_rportfwd pf, *realpf;
6590 ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
6591 pf.sport = ssh_pkt_getuint32(pktin);
6592 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
6593 peerport = ssh_pkt_getuint32(pktin);
6594 realpf = find234(ssh->rportfwds, &pf, NULL);
6595 logeventf(ssh, "Received remote port %d open request "
6596 "from %s:%d", pf.sport, peeraddr, peerport);
6597 if (realpf == NULL) {
6598 error = "Remote port is not recognised";
6600 const char *e = pfd_newconnect(&c->u.pfd.s,
6604 logeventf(ssh, "Attempting to forward remote port to "
6605 "%s:%d", realpf->dhost, realpf->dport);
6607 logeventf(ssh, "Port open failed: %s", e);
6608 error = "Port open failed";
6610 logevent("Forwarded port opened successfully");
6611 c->type = CHAN_SOCKDATA;
6614 } else if (typelen == 22 &&
6615 !memcmp(type, "auth-agent@openssh.com", 3)) {
6616 if (!ssh->agentfwd_enabled)
6617 error = "Agent forwarding is not enabled";
6619 c->type = CHAN_AGENT; /* identify channel type */
6620 c->u.a.lensofar = 0;
6623 error = "Unsupported channel type requested";
6626 c->remoteid = remid;
6628 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
6629 ssh2_pkt_adduint32(s->pktout, c->remoteid);
6630 ssh2_pkt_adduint32(s->pktout, SSH2_OPEN_CONNECT_FAILED);
6631 ssh2_pkt_addstring(s->pktout, error);
6632 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
6633 ssh2_pkt_send(ssh, s->pktout);
6634 logeventf(ssh, "Rejected channel open: %s", error);
6637 c->localid = alloc_channel_id(ssh);
6639 c->v.v2.locwindow = OUR_V2_WINSIZE;
6640 c->v.v2.remwindow = winsize;
6641 c->v.v2.remmaxpkt = pktsize;
6642 bufchain_init(&c->v.v2.outbuffer);
6643 add234(ssh->channels, c);
6644 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
6645 ssh2_pkt_adduint32(s->pktout, c->remoteid);
6646 ssh2_pkt_adduint32(s->pktout, c->localid);
6647 ssh2_pkt_adduint32(s->pktout, c->v.v2.locwindow);
6648 ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
6649 ssh2_pkt_send(ssh, s->pktout);
6652 bombout(("Strange packet received: type %d", pktin->type));
6655 } else if (ssh->mainchan) {
6657 * We have spare data. Add it to the channel buffer.
6659 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
6664 struct ssh_channel *c;
6666 * Try to send data on all channels if we can.
6668 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
6671 continue; /* don't send on closing channels */
6672 bufsize = ssh2_try_send(c);
6675 case CHAN_MAINSESSION:
6676 /* stdin need not receive an unthrottle
6677 * notification since it will be polled */
6680 x11_unthrottle(c->u.x11.s);
6683 /* agent sockets are request/response and need no
6684 * buffer management */
6687 pfd_unthrottle(c->u.pfd.s);
6699 * Handlers for SSH2 messages that might arrive at any moment.
6701 void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
6703 /* log reason code in disconnect message */
6705 int nowlen, reason, msglen;
6707 reason = ssh_pkt_getuint32(pktin);
6708 ssh_pkt_getstring(pktin, &msg, &msglen);
6710 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
6711 buf = dupprintf("Received disconnect message (%s)",
6712 ssh2_disconnect_reasons[reason]);
6714 buf = dupprintf("Received disconnect message (unknown"
6715 " type %d)", reason);
6719 buf = dupprintf("Disconnection message text: %n%.*s",
6720 &nowlen, msglen, msg);
6722 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
6724 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
6725 ssh2_disconnect_reasons[reason] : "unknown",
6730 void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
6732 /* log the debug message */
6737 /* XXX maybe we should actually take notice of this */
6738 always_display = ssh2_pkt_getbool(pktin);
6739 ssh_pkt_getstring(pktin, &msg, &msglen);
6741 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
6746 void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
6748 struct Packet *pktout;
6749 pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
6750 ssh2_pkt_adduint32(pktout, pktin->sequence);
6752 * UNIMPLEMENTED messages MUST appear in the same order as the
6753 * messages they respond to. Hence, never queue them.
6755 ssh2_pkt_send_noqueue(ssh, pktout);
6759 * Handle the top-level SSH2 protocol.
6761 static void ssh2_protocol_setup(Ssh ssh)
6766 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
6768 for (i = 0; i < 256; i++)
6769 ssh->packet_dispatch[i] = ssh2_msg_something_unimplemented;
6772 * Any message we actually understand, we set to NULL so that
6773 * the coroutines will get it.
6775 ssh->packet_dispatch[SSH2_MSG_UNIMPLEMENTED] = NULL;
6776 ssh->packet_dispatch[SSH2_MSG_SERVICE_REQUEST] = NULL;
6777 ssh->packet_dispatch[SSH2_MSG_SERVICE_ACCEPT] = NULL;
6778 ssh->packet_dispatch[SSH2_MSG_KEXINIT] = NULL;
6779 ssh->packet_dispatch[SSH2_MSG_NEWKEYS] = NULL;
6780 ssh->packet_dispatch[SSH2_MSG_KEXDH_INIT] = NULL;
6781 ssh->packet_dispatch[SSH2_MSG_KEXDH_REPLY] = NULL;
6782 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
6783 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
6784 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_INIT] = NULL;
6785 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REPLY] = NULL;
6786 ssh->packet_dispatch[SSH2_MSG_USERAUTH_REQUEST] = NULL;
6787 ssh->packet_dispatch[SSH2_MSG_USERAUTH_FAILURE] = NULL;
6788 ssh->packet_dispatch[SSH2_MSG_USERAUTH_SUCCESS] = NULL;
6789 ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
6790 ssh->packet_dispatch[SSH2_MSG_USERAUTH_PK_OK] = NULL;
6791 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
6792 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
6793 ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_RESPONSE] = NULL;
6794 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] = NULL;
6795 ssh->packet_dispatch[SSH2_MSG_REQUEST_SUCCESS] = NULL;
6796 ssh->packet_dispatch[SSH2_MSG_REQUEST_FAILURE] = NULL;
6797 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] = NULL;
6798 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] = NULL;
6799 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] = NULL;
6800 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] = NULL;
6801 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] = NULL;
6802 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] = NULL;
6803 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = NULL;
6804 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = NULL;
6805 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] = NULL;
6806 ssh->packet_dispatch[SSH2_MSG_CHANNEL_SUCCESS] = NULL;
6807 ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] = NULL;
6810 * These special message types we install handlers for.
6812 ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
6813 ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with ssh1 */
6814 ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
6817 static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
6818 struct Packet *pktin)
6820 if (ssh->state == SSH_STATE_CLOSED)
6823 if (pktin && ssh->packet_dispatch[pktin->type]) {
6824 ssh->packet_dispatch[pktin->type](ssh, pktin);
6828 if (!ssh->protocol_initial_phase_done ||
6829 (pktin && pktin->type >= 20 && pktin->type < 50)) {
6830 if (do_ssh2_transport(ssh, in, inlen, pktin) &&
6831 !ssh->protocol_initial_phase_done) {
6832 ssh->protocol_initial_phase_done = TRUE;
6834 * Allow authconn to initialise itself.
6836 do_ssh2_authconn(ssh, NULL, 0, NULL);
6839 do_ssh2_authconn(ssh, in, inlen, pktin);
6844 * Called to set up the connection.
6846 * Returns an error message, or NULL on success.
6848 static const char *ssh_init(void *frontend_handle, void **backend_handle,
6850 char *host, int port, char **realhost, int nodelay,
6856 ssh = snew(struct ssh_tag);
6857 ssh->cfg = *cfg; /* STRUCTURE COPY */
6858 ssh->version = 0; /* when not ready yet */
6861 ssh->v1_cipher_ctx = NULL;
6862 ssh->crcda_ctx = NULL;
6863 ssh->cscipher = NULL;
6864 ssh->cs_cipher_ctx = NULL;
6865 ssh->sccipher = NULL;
6866 ssh->sc_cipher_ctx = NULL;
6868 ssh->cs_mac_ctx = NULL;
6870 ssh->sc_mac_ctx = NULL;
6872 ssh->cs_comp_ctx = NULL;
6874 ssh->sc_comp_ctx = NULL;
6876 ssh->kex_ctx = NULL;
6877 ssh->hostkey = NULL;
6879 ssh->state = SSH_STATE_PREPACKET;
6880 ssh->size_needed = FALSE;
6881 ssh->eof_needed = FALSE;
6884 ssh->deferred_send_data = NULL;
6885 ssh->deferred_len = 0;
6886 ssh->deferred_size = 0;
6887 ssh->fallback_cmd = 0;
6889 ssh->x11auth = NULL;
6890 ssh->v1_compressing = FALSE;
6891 ssh->v2_outgoing_sequence = 0;
6892 ssh->ssh1_rdpkt_crstate = 0;
6893 ssh->ssh2_rdpkt_crstate = 0;
6894 ssh->do_ssh_init_crstate = 0;
6895 ssh->ssh_gotdata_crstate = 0;
6896 ssh->do_ssh1_connection_crstate = 0;
6897 ssh->do_ssh1_login_crstate = 0;
6898 ssh->do_ssh2_transport_crstate = 0;
6899 ssh->do_ssh2_authconn_crstate = 0;
6900 ssh->do_ssh_init_state = NULL;
6901 ssh->do_ssh1_login_state = NULL;
6902 ssh->do_ssh2_transport_state = NULL;
6903 ssh->do_ssh2_authconn_state = NULL;
6904 ssh->mainchan = NULL;
6905 ssh->throttled_all = 0;
6906 ssh->v1_stdout_throttling = 0;
6908 ssh->queuelen = ssh->queuesize = 0;
6909 ssh->queueing = FALSE;
6911 *backend_handle = ssh;
6914 if (crypto_startup() == 0)
6915 return "Microsoft high encryption pack not installed!";
6918 ssh->frontend = frontend_handle;
6919 ssh->term_width = ssh->cfg.width;
6920 ssh->term_height = ssh->cfg.height;
6922 ssh->channels = NULL;
6923 ssh->rportfwds = NULL;
6928 ssh->v1_throttle_count = 0;
6929 ssh->overall_bufsize = 0;
6930 ssh->fallback_cmd = 0;
6932 ssh->protocol = NULL;
6934 ssh->protocol_initial_phase_done = FALSE;
6936 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
6943 static void ssh_free(void *handle)
6945 Ssh ssh = (Ssh) handle;
6946 struct ssh_channel *c;
6947 struct ssh_rportfwd *pf;
6949 if (ssh->v1_cipher_ctx)
6950 ssh->cipher->free_context(ssh->v1_cipher_ctx);
6951 if (ssh->cs_cipher_ctx)
6952 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
6953 if (ssh->sc_cipher_ctx)
6954 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
6955 if (ssh->cs_mac_ctx)
6956 ssh->csmac->free_context(ssh->cs_mac_ctx);
6957 if (ssh->sc_mac_ctx)
6958 ssh->scmac->free_context(ssh->sc_mac_ctx);
6959 if (ssh->cs_comp_ctx) {
6961 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
6963 zlib_compress_cleanup(ssh->cs_comp_ctx);
6965 if (ssh->sc_comp_ctx) {
6967 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
6969 zlib_decompress_cleanup(ssh->sc_comp_ctx);
6972 dh_cleanup(ssh->kex_ctx);
6973 sfree(ssh->savedhost);
6975 while (ssh->queuelen-- > 0)
6976 ssh_free_packet(ssh->queue[ssh->queuelen]);
6979 if (ssh->channels) {
6980 while ((c = delpos234(ssh->channels, 0)) != NULL) {
6983 if (c->u.x11.s != NULL)
6984 x11_close(c->u.x11.s);
6987 if (c->u.pfd.s != NULL)
6988 pfd_close(c->u.pfd.s);
6993 freetree234(ssh->channels);
6996 if (ssh->rportfwds) {
6997 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
6999 freetree234(ssh->rportfwds);
7001 sfree(ssh->deferred_send_data);
7003 x11_free_auth(ssh->x11auth);
7004 sfree(ssh->do_ssh_init_state);
7005 sfree(ssh->do_ssh1_login_state);
7006 sfree(ssh->do_ssh2_transport_state);
7007 sfree(ssh->do_ssh2_authconn_state);
7008 if (ssh->crcda_ctx) {
7009 crcda_free_context(ssh->crcda_ctx);
7010 ssh->crcda_ctx = NULL;
7018 * Reconfigure the SSH backend.
7020 * Currently, this function does nothing very useful. In future,
7021 * however, we could do some handy things with it. For example, we
7022 * could make the port forwarding configurer active in the Change
7023 * Settings box, and this routine could close down existing
7024 * forwardings and open up new ones in response to changes.
7026 static void ssh_reconfig(void *handle, Config *cfg)
7028 Ssh ssh = (Ssh) handle;
7029 ssh->cfg = *cfg; /* STRUCTURE COPY */
7033 * Called to send data down the Telnet connection.
7035 static int ssh_send(void *handle, char *buf, int len)
7037 Ssh ssh = (Ssh) handle;
7039 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
7042 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
7044 return ssh_sendbuffer(ssh);
7048 * Called to query the current amount of buffered stdin data.
7050 static int ssh_sendbuffer(void *handle)
7052 Ssh ssh = (Ssh) handle;
7055 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
7059 * If the SSH socket itself has backed up, add the total backup
7060 * size on that to any individual buffer on the stdin channel.
7063 if (ssh->throttled_all)
7064 override_value = ssh->overall_bufsize;
7066 if (ssh->version == 1) {
7067 return override_value;
7068 } else if (ssh->version == 2) {
7069 if (!ssh->mainchan || ssh->mainchan->closes > 0)
7070 return override_value;
7072 return (override_value +
7073 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
7080 * Called to set the size of the window from SSH's POV.
7082 static void ssh_size(void *handle, int width, int height)
7084 Ssh ssh = (Ssh) handle;
7085 struct Packet *pktout;
7087 ssh->term_width = width;
7088 ssh->term_height = height;
7090 switch (ssh->state) {
7091 case SSH_STATE_BEFORE_SIZE:
7092 case SSH_STATE_PREPACKET:
7093 case SSH_STATE_CLOSED:
7094 break; /* do nothing */
7095 case SSH_STATE_INTERMED:
7096 ssh->size_needed = TRUE; /* buffer for later */
7098 case SSH_STATE_SESSION:
7099 if (!ssh->cfg.nopty) {
7100 if (ssh->version == 1) {
7101 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
7102 PKT_INT, ssh->term_height,
7103 PKT_INT, ssh->term_width,
7104 PKT_INT, 0, PKT_INT, 0, PKT_END);
7105 } else if (ssh->mainchan) {
7106 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7107 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7108 ssh2_pkt_addstring(pktout, "window-change");
7109 ssh2_pkt_addbool(pktout, 0);
7110 ssh2_pkt_adduint32(pktout, ssh->term_width);
7111 ssh2_pkt_adduint32(pktout, ssh->term_height);
7112 ssh2_pkt_adduint32(pktout, 0);
7113 ssh2_pkt_adduint32(pktout, 0);
7114 ssh2_pkt_send(ssh, pktout);
7122 * Return a list of the special codes that make sense in this
7125 static const struct telnet_special *ssh_get_specials(void *handle)
7127 static const struct telnet_special ignore_special[] = {
7128 {"IGNORE message", TS_NOP},
7130 static const struct telnet_special ssh2_session_specials[] = {
7133 /* These are the signal names defined by draft-ietf-secsh-connect-19.
7134 * They include all the ISO C signals, but are a subset of the POSIX
7135 * required signals. */
7136 {"SIGINT (Interrupt)", TS_SIGINT},
7137 {"SIGTERM (Terminate)", TS_SIGTERM},
7138 {"SIGKILL (Kill)", TS_SIGKILL},
7139 {"SIGQUIT (Quit)", TS_SIGQUIT},
7140 {"SIGHUP (Hangup)", TS_SIGHUP},
7141 {"More signals", TS_SUBMENU},
7142 {"SIGABRT", TS_SIGABRT}, {"SIGALRM", TS_SIGALRM},
7143 {"SIGFPE", TS_SIGFPE}, {"SIGILL", TS_SIGILL},
7144 {"SIGPIPE", TS_SIGPIPE}, {"SIGSEGV", TS_SIGSEGV},
7145 {"SIGUSR1", TS_SIGUSR1}, {"SIGUSR2", TS_SIGUSR2},
7148 static const struct telnet_special specials_end[] = {
7151 static struct telnet_special ssh_specials[lenof(ignore_special) +
7152 lenof(ssh2_session_specials) +
7153 lenof(specials_end)];
7154 Ssh ssh = (Ssh) handle;
7156 #define ADD_SPECIALS(name) \
7158 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7159 memcpy(&ssh_specials[i], name, sizeof name); \
7163 if (ssh->version == 1) {
7164 /* Don't bother offering IGNORE if we've decided the remote
7165 * won't cope with it, since we wouldn't bother sending it if
7167 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
7168 ADD_SPECIALS(ignore_special);
7169 } else if (ssh->version == 2) {
7170 /* XXX add rekey, when implemented */
7171 ADD_SPECIALS(ignore_special);
7173 ADD_SPECIALS(ssh2_session_specials);
7174 } /* else we're not ready yet */
7177 ADD_SPECIALS(specials_end);
7178 return ssh_specials;
7186 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7187 * can send an EOF and collect resulting output (e.g. `plink
7190 static void ssh_special(void *handle, Telnet_Special code)
7192 Ssh ssh = (Ssh) handle;
7193 struct Packet *pktout;
7195 if (code == TS_EOF) {
7196 if (ssh->state != SSH_STATE_SESSION) {
7198 * Buffer the EOF in case we are pre-SESSION, so we can
7199 * send it as soon as we reach SESSION.
7202 ssh->eof_needed = TRUE;
7205 if (ssh->version == 1) {
7206 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
7207 } else if (ssh->mainchan) {
7208 struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
7209 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7210 ssh2_pkt_send(ssh, pktout);
7212 logevent("Sent EOF message");
7213 } else if (code == TS_PING || code == TS_NOP) {
7214 if (ssh->state == SSH_STATE_CLOSED
7215 || ssh->state == SSH_STATE_PREPACKET) return;
7216 if (ssh->version == 1) {
7217 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
7218 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
7220 pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
7221 ssh2_pkt_addstring_start(pktout);
7222 ssh2_pkt_send_noqueue(ssh, pktout);
7224 } else if (code == TS_BRK) {
7225 if (ssh->state == SSH_STATE_CLOSED
7226 || ssh->state == SSH_STATE_PREPACKET) return;
7227 if (ssh->version == 1) {
7228 logevent("Unable to send BREAK signal in SSH1");
7229 } else if (ssh->mainchan) {
7230 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7231 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7232 ssh2_pkt_addstring(pktout, "break");
7233 ssh2_pkt_addbool(pktout, 0);
7234 ssh2_pkt_adduint32(pktout, 0); /* default break length */
7235 ssh2_pkt_send(ssh, pktout);
7238 /* Is is a POSIX signal? */
7239 char *signame = NULL;
7240 if (code == TS_SIGABRT) signame = "ABRT";
7241 if (code == TS_SIGALRM) signame = "ALRM";
7242 if (code == TS_SIGFPE) signame = "FPE";
7243 if (code == TS_SIGHUP) signame = "HUP";
7244 if (code == TS_SIGILL) signame = "ILL";
7245 if (code == TS_SIGINT) signame = "INT";
7246 if (code == TS_SIGKILL) signame = "KILL";
7247 if (code == TS_SIGPIPE) signame = "PIPE";
7248 if (code == TS_SIGQUIT) signame = "QUIT";
7249 if (code == TS_SIGSEGV) signame = "SEGV";
7250 if (code == TS_SIGTERM) signame = "TERM";
7251 if (code == TS_SIGUSR1) signame = "USR1";
7252 if (code == TS_SIGUSR2) signame = "USR2";
7253 /* The SSH-2 protocol does in principle support arbitrary named
7254 * signals, including signame@domain, but we don't support those. */
7256 /* It's a signal. */
7257 if (ssh->version == 2 && ssh->mainchan) {
7258 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7259 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7260 ssh2_pkt_addstring(pktout, "signal");
7261 ssh2_pkt_addbool(pktout, 0);
7262 ssh2_pkt_addstring(pktout, signame);
7263 ssh2_pkt_send(ssh, pktout);
7264 logeventf(ssh, "Sent signal SIG%s", signame);
7267 /* Never heard of it. Do nothing */
7272 void *new_sock_channel(void *handle, Socket s)
7274 Ssh ssh = (Ssh) handle;
7275 struct ssh_channel *c;
7276 c = snew(struct ssh_channel);
7280 c->remoteid = -1; /* to be set when open confirmed */
7281 c->localid = alloc_channel_id(ssh);
7283 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
7285 bufchain_init(&c->v.v2.outbuffer);
7286 add234(ssh->channels, c);
7292 * This is called when stdout/stderr (the entity to which
7293 * from_backend sends data) manages to clear some backlog.
7295 static void ssh_unthrottle(void *handle, int bufsize)
7297 Ssh ssh = (Ssh) handle;
7298 if (ssh->version == 1) {
7299 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
7300 ssh->v1_stdout_throttling = 0;
7301 ssh1_throttle(ssh, -1);
7304 if (ssh->mainchan && ssh->mainchan->closes == 0)
7305 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
7309 void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
7311 struct ssh_channel *c = (struct ssh_channel *)channel;
7313 struct Packet *pktout;
7315 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
7317 if (ssh->version == 1) {
7318 send_packet(ssh, SSH1_MSG_PORT_OPEN,
7319 PKT_INT, c->localid,
7322 //PKT_STR, <org:orgport>,
7325 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
7326 ssh2_pkt_addstring(pktout, "direct-tcpip");
7327 ssh2_pkt_adduint32(pktout, c->localid);
7328 c->v.v2.locwindow = OUR_V2_WINSIZE;
7329 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
7330 ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
7331 ssh2_pkt_addstring(pktout, hostname);
7332 ssh2_pkt_adduint32(pktout, port);
7334 * We make up values for the originator data; partly it's
7335 * too much hassle to keep track, and partly I'm not
7336 * convinced the server should be told details like that
7337 * about my local network configuration.
7339 ssh2_pkt_addstring(pktout, "client-side-connection");
7340 ssh2_pkt_adduint32(pktout, 0);
7341 ssh2_pkt_send(ssh, pktout);
7345 static Socket ssh_socket(void *handle)
7347 Ssh ssh = (Ssh) handle;
7351 static int ssh_sendok(void *handle)
7353 Ssh ssh = (Ssh) handle;
7354 return ssh->send_ok;
7357 static int ssh_ldisc(void *handle, int option)
7359 Ssh ssh = (Ssh) handle;
7360 if (option == LD_ECHO)
7361 return ssh->echoing;
7362 if (option == LD_EDIT)
7363 return ssh->editing;
7367 static void ssh_provide_ldisc(void *handle, void *ldisc)
7369 Ssh ssh = (Ssh) handle;
7373 static void ssh_provide_logctx(void *handle, void *logctx)
7375 Ssh ssh = (Ssh) handle;
7376 ssh->logctx = logctx;
7379 static int ssh_return_exitcode(void *handle)
7381 Ssh ssh = (Ssh) handle;
7385 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
7389 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7390 * that fails. This variable is the means by which scp.c can reach
7391 * into the SSH code and find out which one it got.
7393 extern int ssh_fallback_cmd(void *handle)
7395 Ssh ssh = (Ssh) handle;
7396 return ssh->fallback_cmd;
7399 Backend ssh_backend = {
7409 ssh_return_exitcode,