18 #define logevent(s) { logevent(s); \
19 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
20 { fprintf(stderr, "%s\n", s); fflush(stderr); } }
22 #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \
23 (s ? sk_close(s), s = NULL : 0), \
24 connection_fatal msg )
26 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
27 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
28 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
29 #define SSH1_CMSG_USER 4 /* 0x4 */
30 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
31 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
32 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
33 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
34 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
35 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
36 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
37 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
38 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
39 #define SSH1_SMSG_FAILURE 15 /* 0xf */
40 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
41 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
42 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
43 #define SSH1_CMSG_EOF 19 /* 0x13 */
44 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
45 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
46 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
47 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
48 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
49 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
50 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
51 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
52 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
53 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
54 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
55 #define SSH1_MSG_IGNORE 32 /* 0x20 */
56 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
57 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
58 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
59 #define SSH1_MSG_DEBUG 36 /* 0x24 */
60 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
61 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
62 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
63 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
64 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
65 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
66 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
68 #define SSH1_AUTH_TIS 5 /* 0x5 */
69 #define SSH1_AUTH_CCARD 16 /* 0x10 */
71 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
72 /* Mask for protoflags we will echo back to server if seen */
73 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
75 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
76 #define SSH2_MSG_IGNORE 2 /* 0x2 */
77 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
78 #define SSH2_MSG_DEBUG 4 /* 0x4 */
79 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
80 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
81 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
82 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
83 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
84 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
85 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
86 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
87 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
88 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
89 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
90 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
91 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
92 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
93 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
94 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
95 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
96 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
97 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
98 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
99 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
100 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
101 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
102 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
103 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
104 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
105 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
106 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
107 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
108 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
109 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
110 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
113 * Packet type contexts, so that ssh2_pkt_type can correctly decode
114 * the ambiguous type numbers back into the correct type strings.
116 #define SSH2_PKTCTX_DHGROUP1 0x0001
117 #define SSH2_PKTCTX_DHGEX 0x0002
118 #define SSH2_PKTCTX_PUBLICKEY 0x0010
119 #define SSH2_PKTCTX_PASSWORD 0x0020
120 #define SSH2_PKTCTX_KBDINTER 0x0040
121 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
123 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
124 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
125 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
126 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
127 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
128 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
129 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
130 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
131 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
132 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
133 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
134 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
135 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
136 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
137 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
139 static const char *const ssh2_disconnect_reasons[] = {
141 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
142 "SSH_DISCONNECT_PROTOCOL_ERROR",
143 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
144 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
145 "SSH_DISCONNECT_MAC_ERROR",
146 "SSH_DISCONNECT_COMPRESSION_ERROR",
147 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
148 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
149 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
150 "SSH_DISCONNECT_CONNECTION_LOST",
151 "SSH_DISCONNECT_BY_APPLICATION",
152 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
153 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
154 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
155 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
158 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
159 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
160 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
161 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
163 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
166 * Various remote-bug flags.
168 #define BUG_CHOKES_ON_SSH1_IGNORE 1
169 #define BUG_SSH2_HMAC 2
170 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
171 #define BUG_CHOKES_ON_RSA 8
173 static int ssh_pkt_ctx = 0;
175 #define translate(x) if (type == x) return #x
176 #define translatec(x,ctx) if (type == x && (ssh_pkt_ctx & ctx)) return #x
177 char *ssh1_pkt_type(int type)
179 translate(SSH1_MSG_DISCONNECT);
180 translate(SSH1_SMSG_PUBLIC_KEY);
181 translate(SSH1_CMSG_SESSION_KEY);
182 translate(SSH1_CMSG_USER);
183 translate(SSH1_CMSG_AUTH_RSA);
184 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
185 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
186 translate(SSH1_CMSG_AUTH_PASSWORD);
187 translate(SSH1_CMSG_REQUEST_PTY);
188 translate(SSH1_CMSG_WINDOW_SIZE);
189 translate(SSH1_CMSG_EXEC_SHELL);
190 translate(SSH1_CMSG_EXEC_CMD);
191 translate(SSH1_SMSG_SUCCESS);
192 translate(SSH1_SMSG_FAILURE);
193 translate(SSH1_CMSG_STDIN_DATA);
194 translate(SSH1_SMSG_STDOUT_DATA);
195 translate(SSH1_SMSG_STDERR_DATA);
196 translate(SSH1_CMSG_EOF);
197 translate(SSH1_SMSG_EXIT_STATUS);
198 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
199 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
200 translate(SSH1_MSG_CHANNEL_DATA);
201 translate(SSH1_MSG_CHANNEL_CLOSE);
202 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
203 translate(SSH1_SMSG_X11_OPEN);
204 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
205 translate(SSH1_MSG_PORT_OPEN);
206 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
207 translate(SSH1_SMSG_AGENT_OPEN);
208 translate(SSH1_MSG_IGNORE);
209 translate(SSH1_CMSG_EXIT_CONFIRMATION);
210 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
211 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
212 translate(SSH1_MSG_DEBUG);
213 translate(SSH1_CMSG_REQUEST_COMPRESSION);
214 translate(SSH1_CMSG_AUTH_TIS);
215 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
216 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
217 translate(SSH1_CMSG_AUTH_CCARD);
218 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
219 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
222 char *ssh2_pkt_type(int type)
224 translate(SSH2_MSG_DISCONNECT);
225 translate(SSH2_MSG_IGNORE);
226 translate(SSH2_MSG_UNIMPLEMENTED);
227 translate(SSH2_MSG_DEBUG);
228 translate(SSH2_MSG_SERVICE_REQUEST);
229 translate(SSH2_MSG_SERVICE_ACCEPT);
230 translate(SSH2_MSG_KEXINIT);
231 translate(SSH2_MSG_NEWKEYS);
232 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP1);
233 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP1);
234 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
235 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
236 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
237 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
238 translate(SSH2_MSG_USERAUTH_REQUEST);
239 translate(SSH2_MSG_USERAUTH_FAILURE);
240 translate(SSH2_MSG_USERAUTH_SUCCESS);
241 translate(SSH2_MSG_USERAUTH_BANNER);
242 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
243 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
244 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
245 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
246 translate(SSH2_MSG_GLOBAL_REQUEST);
247 translate(SSH2_MSG_REQUEST_SUCCESS);
248 translate(SSH2_MSG_REQUEST_FAILURE);
249 translate(SSH2_MSG_CHANNEL_OPEN);
250 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
251 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
252 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
253 translate(SSH2_MSG_CHANNEL_DATA);
254 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
255 translate(SSH2_MSG_CHANNEL_EOF);
256 translate(SSH2_MSG_CHANNEL_CLOSE);
257 translate(SSH2_MSG_CHANNEL_REQUEST);
258 translate(SSH2_MSG_CHANNEL_SUCCESS);
259 translate(SSH2_MSG_CHANNEL_FAILURE);
265 #define GET_32BIT(cp) \
266 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
267 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
268 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
269 ((unsigned long)(unsigned char)(cp)[3]))
271 #define PUT_32BIT(cp, value) { \
272 (cp)[0] = (unsigned char)((value) >> 24); \
273 (cp)[1] = (unsigned char)((value) >> 16); \
274 (cp)[2] = (unsigned char)((value) >> 8); \
275 (cp)[3] = (unsigned char)(value); }
277 enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
279 /* Coroutine mechanics for the sillier bits of the code */
280 #define crBegin1 static int crLine = 0;
281 #define crBegin2 switch(crLine) { case 0:;
282 #define crBegin crBegin1; crBegin2;
283 #define crFinish(z) } crLine = 0; return (z)
284 #define crFinishV } crLine = 0; return
285 #define crReturn(z) \
287 crLine=__LINE__; return (z); case __LINE__:;\
291 crLine=__LINE__; return; case __LINE__:;\
293 #define crStop(z) do{ crLine = 0; return (z); }while(0)
294 #define crStopV do{ crLine = 0; return; }while(0)
295 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
296 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
298 extern char *x11_init(Socket *, char *, void *);
299 extern void x11_close(Socket);
300 extern int x11_send(Socket, char *, int);
301 extern void x11_invent_auth(char *, int, char *, int);
302 extern void x11_unthrottle(Socket s);
303 extern void x11_override_throttle(Socket s, int enable);
305 extern char *pfd_newconnect(Socket * s, char *hostname, int port, void *c);
306 extern char *pfd_addforward(char *desthost, int destport, int port);
307 extern void pfd_close(Socket s);
308 extern int pfd_send(Socket s, char *data, int len);
309 extern void pfd_confirm(Socket s);
310 extern void pfd_unthrottle(Socket s);
311 extern void pfd_override_throttle(Socket s, int enable);
313 static void ssh2_pkt_init(int pkt_type);
314 static void ssh2_pkt_addbool(unsigned char value);
315 static void ssh2_pkt_adduint32(unsigned long value);
316 static void ssh2_pkt_addstring_start(void);
317 static void ssh2_pkt_addstring_str(char *data);
318 static void ssh2_pkt_addstring_data(char *data, int len);
319 static void ssh2_pkt_addstring(char *data);
320 static char *ssh2_mpint_fmt(Bignum b, int *len);
321 static void ssh2_pkt_addmp(Bignum b);
322 static int ssh2_pkt_construct(void);
323 static void ssh2_pkt_send(void);
326 * Buffer management constants. There are several of these for
327 * various different purposes:
329 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
330 * on a local data stream before we throttle the whole SSH
331 * connection (in SSH1 only). Throttling the whole connection is
332 * pretty drastic so we set this high in the hope it won't
335 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
336 * on the SSH connection itself before we defensively throttle
337 * _all_ local data streams. This is pretty drastic too (though
338 * thankfully unlikely in SSH2 since the window mechanism should
339 * ensure that the server never has any need to throttle its end
340 * of the connection), so we set this high as well.
342 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
346 #define SSH1_BUFFER_LIMIT 32768
347 #define SSH_MAX_BACKLOG 32768
348 #define OUR_V2_WINSIZE 16384
350 const static struct ssh_kex *kex_algs[] = {
351 &ssh_diffiehellman_gex,
355 const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
357 static void nullmac_key(unsigned char *key)
360 static void nullmac_generate(unsigned char *blk, int len,
364 static int nullmac_verify(unsigned char *blk, int len, unsigned long seq)
368 const static struct ssh_mac ssh_mac_none = {
369 nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
371 const static struct ssh_mac *macs[] = {
372 &ssh_sha1, &ssh_md5, &ssh_mac_none
374 const static struct ssh_mac *buggymacs[] = {
375 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
378 static void ssh_comp_none_init(void)
381 static int ssh_comp_none_block(unsigned char *block, int len,
382 unsigned char **outblock, int *outlen)
386 static int ssh_comp_none_disable(void)
390 const static struct ssh_compress ssh_comp_none = {
392 ssh_comp_none_init, ssh_comp_none_block,
393 ssh_comp_none_init, ssh_comp_none_block,
394 ssh_comp_none_disable
396 extern const struct ssh_compress ssh_zlib;
397 const static struct ssh_compress *compressions[] = {
398 &ssh_zlib, &ssh_comp_none
401 enum { /* channel types */
406 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
410 * 2-3-4 tree storing channels.
413 unsigned remoteid, localid;
417 struct ssh1_data_channel {
420 struct ssh2_data_channel {
422 unsigned remwindow, remmaxpkt;
427 struct ssh_agent_channel {
428 unsigned char *message;
429 unsigned char msglen[4];
430 int lensofar, totallen;
432 struct ssh_x11_channel {
435 struct ssh_pfd_channel {
442 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
443 * 2 use this structure in different ways, reflecting SSH 2's
444 * altogether saner approach to port forwarding.
446 * In SSH 1, you arrange a remote forwarding by sending the server
447 * the remote port number, and the local destination host:port.
448 * When a connection comes in, the server sends you back that
449 * host:port pair, and you connect to it. This is a ready-made
450 * security hole if you're not on the ball: a malicious server
451 * could send you back _any_ host:port pair, so if you trustingly
452 * connect to the address it gives you then you've just opened the
453 * entire inside of your corporate network just by connecting
454 * through it to a dodgy SSH server. Hence, we must store a list of
455 * host:port pairs we _are_ trying to forward to, and reject a
456 * connection request from the server if it's not in the list.
458 * In SSH 2, each side of the connection minds its own business and
459 * doesn't send unnecessary information to the other. You arrange a
460 * remote forwarding by sending the server just the remote port
461 * number. When a connection comes in, the server tells you which
462 * of its ports was connected to; and _you_ have to remember what
463 * local host:port pair went with that port number.
465 * Hence: in SSH 1 this structure stores host:port pairs we intend
466 * to allow connections to, and is indexed by those host:port
467 * pairs. In SSH 2 it stores a mapping from source port to
468 * destination host:port pair, and is indexed by source port.
470 struct ssh_rportfwd {
471 unsigned sport, dport;
484 static SHA_State exhash, exhashbase;
486 static Socket s = NULL;
488 static unsigned char session_key[32];
489 static int ssh1_compressing;
490 static int ssh1_remote_protoflags;
491 static int ssh1_local_protoflags;
492 static int ssh_agentfwd_enabled;
493 static int ssh_X11_fwd_enabled;
494 static int ssh_remote_bugs;
495 static const struct ssh_cipher *cipher = NULL;
496 static const struct ssh2_cipher *cscipher = NULL;
497 static const struct ssh2_cipher *sccipher = NULL;
498 static const struct ssh_mac *csmac = NULL;
499 static const struct ssh_mac *scmac = NULL;
500 static const struct ssh_compress *cscomp = NULL;
501 static const struct ssh_compress *sccomp = NULL;
502 static const struct ssh_kex *kex = NULL;
503 static const struct ssh_signkey *hostkey = NULL;
504 static unsigned char ssh2_session_id[20];
505 int (*ssh_get_line) (const char *prompt, char *str, int maxlen,
508 static char *savedhost;
509 static int savedport;
510 static int ssh_send_ok;
511 static int ssh_echoing, ssh_editing;
513 static tree234 *ssh_channels; /* indexed by local id */
514 static struct ssh_channel *mainchan; /* primary session channel */
515 static int ssh_exitcode = -1;
517 static tree234 *ssh_rportfwds;
521 SSH_STATE_BEFORE_SIZE,
525 } ssh_state = SSH_STATE_PREPACKET;
527 static int size_needed = FALSE, eof_needed = FALSE;
529 static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
530 static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
531 static unsigned char *deferred_send_data = NULL;
532 static int deferred_len = 0, deferred_size = 0;
535 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
536 * that fails. This variable is the means by which scp.c can reach
537 * into the SSH code and find out which one it got.
539 int ssh_fallback_cmd = 0;
541 static int ssh_version;
542 static int ssh1_throttle_count;
543 static int ssh_overall_bufsize;
544 static int ssh_throttled_all;
545 static int ssh1_stdout_throttling;
546 static void (*ssh_protocol) (unsigned char *in, int inlen, int ispkt);
547 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
548 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
549 static void ssh_size(void);
550 static void ssh_special(Telnet_Special);
551 static int ssh2_try_send(struct ssh_channel *c);
552 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
554 static void ssh_throttle_all(int enable, int bufsize);
555 static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
556 static int (*s_rdpkt) (unsigned char **data, int *datalen);
557 static int ssh_sendbuffer(void);
559 static struct rdpkt1_state_tag {
560 long len, pad, biglen, to_read;
561 unsigned long realcrc, gotcrc;
567 static struct rdpkt2_state_tag {
568 long len, pad, payload, packetlen, maclen;
571 unsigned long incoming_sequence;
574 static int ssh_channelcmp(void *av, void *bv)
576 struct ssh_channel *a = (struct ssh_channel *) av;
577 struct ssh_channel *b = (struct ssh_channel *) bv;
578 if (a->localid < b->localid)
580 if (a->localid > b->localid)
584 static int ssh_channelfind(void *av, void *bv)
586 unsigned *a = (unsigned *) av;
587 struct ssh_channel *b = (struct ssh_channel *) bv;
595 static int ssh_rportcmp_ssh1(void *av, void *bv)
597 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
598 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
600 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
601 return i < 0 ? -1 : +1;
602 if (a->dport > b->dport)
604 if (a->dport < b->dport)
609 static int ssh_rportcmp_ssh2(void *av, void *bv)
611 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
612 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
614 if (a->sport > b->sport)
616 if (a->sport < b->sport)
621 static int alloc_channel_id(void)
623 const unsigned CHANNEL_NUMBER_OFFSET = 256;
624 unsigned low, high, mid;
626 struct ssh_channel *c;
629 * First-fit allocation of channel numbers: always pick the
630 * lowest unused one. To do this, binary-search using the
631 * counted B-tree to find the largest channel ID which is in a
632 * contiguous sequence from the beginning. (Precisely
633 * everything in that sequence must have ID equal to its tree
634 * index plus CHANNEL_NUMBER_OFFSET.)
636 tsize = count234(ssh_channels);
640 while (high - low > 1) {
641 mid = (high + low) / 2;
642 c = index234(ssh_channels, mid);
643 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
644 low = mid; /* this one is fine */
646 high = mid; /* this one is past it */
649 * Now low points to either -1, or the tree index of the
650 * largest ID in the initial sequence.
653 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
654 assert(NULL == find234(ssh_channels, &i, ssh_channelfind));
656 return low + 1 + CHANNEL_NUMBER_OFFSET;
659 static void c_write(char *buf, int len)
661 if ((flags & FLAG_STDERR)) {
663 for (i = 0; i < len; i++)
665 fputc(buf[i], stderr);
668 from_backend(1, buf, len);
671 static void c_write_untrusted(char *buf, int len)
674 for (i = 0; i < len; i++) {
677 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
682 static void c_write_str(char *buf)
684 c_write(buf, strlen(buf));
688 * Collect incoming data in the incoming packet buffer.
689 * Decipher and verify the packet when it is completely read.
690 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
691 * Update the *data and *datalen variables.
692 * Return the additional nr of bytes needed, or 0 when
693 * a complete packet is available.
695 static int ssh1_rdpkt(unsigned char **data, int *datalen)
697 struct rdpkt1_state_tag *st = &rdpkt1_state;
706 for (st->i = st->len = 0; st->i < 4; st->i++) {
707 while ((*datalen) == 0)
709 st->len = (st->len << 8) + **data;
710 (*data)++, (*datalen)--;
713 st->pad = 8 - (st->len % 8);
714 st->biglen = st->len + st->pad;
715 pktin.length = st->len - 5;
717 if (pktin.maxlen < st->biglen) {
718 pktin.maxlen = st->biglen;
719 pktin.data = (pktin.data == NULL ? smalloc(st->biglen + APIEXTRA) :
720 srealloc(pktin.data, st->biglen + APIEXTRA));
722 fatalbox("Out of memory");
725 st->to_read = st->biglen;
727 while (st->to_read > 0) {
728 st->chunk = st->to_read;
729 while ((*datalen) == 0)
730 crReturn(st->to_read);
731 if (st->chunk > (*datalen))
732 st->chunk = (*datalen);
733 memcpy(st->p, *data, st->chunk);
735 *datalen -= st->chunk;
737 st->to_read -= st->chunk;
740 if (cipher && detect_attack(pktin.data, st->biglen, NULL)) {
741 bombout(("Network attack (CRC compensation) detected!"));
746 cipher->decrypt(pktin.data, st->biglen);
748 st->realcrc = crc32(pktin.data, st->biglen - 4);
749 st->gotcrc = GET_32BIT(pktin.data + st->biglen - 4);
750 if (st->gotcrc != st->realcrc) {
751 bombout(("Incorrect CRC received on packet"));
755 pktin.body = pktin.data + st->pad + 1;
757 if (ssh1_compressing) {
758 unsigned char *decompblk;
760 zlib_decompress_block(pktin.body - 1, pktin.length + 1,
761 &decompblk, &decomplen);
763 if (pktin.maxlen < st->pad + decomplen) {
764 pktin.maxlen = st->pad + decomplen;
765 pktin.data = srealloc(pktin.data, pktin.maxlen + APIEXTRA);
766 pktin.body = pktin.data + st->pad + 1;
768 fatalbox("Out of memory");
771 memcpy(pktin.body - 1, decompblk, decomplen);
773 pktin.length = decomplen - 1;
776 pktin.type = pktin.body[-1];
778 log_packet(PKT_INCOMING, pktin.type, ssh1_pkt_type(pktin.type),
779 pktin.body, pktin.length);
781 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
782 pktin.type == SSH1_SMSG_STDERR_DATA ||
783 pktin.type == SSH1_MSG_DEBUG ||
784 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
785 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
786 long stringlen = GET_32BIT(pktin.body);
787 if (stringlen + 4 != pktin.length) {
788 bombout(("Received data packet with bogus string length"));
793 if (pktin.type == SSH1_MSG_DEBUG) {
794 /* log debug message */
796 int stringlen = GET_32BIT(pktin.body);
797 strcpy(buf, "Remote: ");
800 memcpy(buf + 8, pktin.body + 4, stringlen);
801 buf[8 + stringlen] = '\0';
804 } else if (pktin.type == SSH1_MSG_IGNORE) {
809 if (pktin.type == SSH1_MSG_DISCONNECT) {
810 /* log reason code in disconnect message */
812 unsigned msglen = GET_32BIT(pktin.body);
814 strcpy(buf, "Remote sent disconnect: ");
815 nowlen = strlen(buf);
816 if (msglen > sizeof(buf) - nowlen - 1)
817 msglen = sizeof(buf) - nowlen - 1;
818 memcpy(buf + nowlen, pktin.body + 4, msglen);
819 buf[nowlen + msglen] = '\0';
821 bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen));
828 static int ssh2_rdpkt(unsigned char **data, int *datalen)
830 struct rdpkt2_state_tag *st = &rdpkt2_state;
838 st->cipherblk = sccipher->blksize;
841 if (st->cipherblk < 8)
844 if (pktin.maxlen < st->cipherblk) {
845 pktin.maxlen = st->cipherblk;
848 NULL ? smalloc(st->cipherblk +
849 APIEXTRA) : srealloc(pktin.data,
853 fatalbox("Out of memory");
857 * Acquire and decrypt the first block of the packet. This will
858 * contain the length and padding details.
860 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
861 while ((*datalen) == 0)
862 crReturn(st->cipherblk - st->i);
863 pktin.data[st->i] = *(*data)++;
868 sccipher->decrypt(pktin.data, st->cipherblk);
871 * Now get the length and padding figures.
873 st->len = GET_32BIT(pktin.data);
874 st->pad = pktin.data[4];
877 * This enables us to deduce the payload length.
879 st->payload = st->len - st->pad - 1;
881 pktin.length = st->payload + 5;
884 * So now we can work out the total packet length.
886 st->packetlen = st->len + 4;
887 st->maclen = scmac ? scmac->len : 0;
890 * Adjust memory allocation if packet is too big.
892 if (pktin.maxlen < st->packetlen + st->maclen) {
893 pktin.maxlen = st->packetlen + st->maclen;
896 NULL ? smalloc(pktin.maxlen + APIEXTRA) : srealloc(pktin.data,
901 fatalbox("Out of memory");
905 * Read and decrypt the remainder of the packet.
907 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
909 while ((*datalen) == 0)
910 crReturn(st->packetlen + st->maclen - st->i);
911 pktin.data[st->i] = *(*data)++;
914 /* Decrypt everything _except_ the MAC. */
916 sccipher->decrypt(pktin.data + st->cipherblk,
917 st->packetlen - st->cipherblk);
923 && !scmac->verify(pktin.data, st->len + 4,
924 st->incoming_sequence)) {
925 bombout(("Incorrect MAC received on packet"));
928 st->incoming_sequence++; /* whether or not we MACed */
931 * Decompress packet payload.
934 unsigned char *newpayload;
936 if (sccomp && sccomp->decompress(pktin.data + 5, pktin.length - 5,
937 &newpayload, &newlen)) {
938 if (pktin.maxlen < newlen + 5) {
939 pktin.maxlen = newlen + 5;
942 NULL ? smalloc(pktin.maxlen +
943 APIEXTRA) : srealloc(pktin.data,
947 fatalbox("Out of memory");
949 pktin.length = 5 + newlen;
950 memcpy(pktin.data + 5, newpayload, newlen);
956 pktin.type = pktin.data[5];
958 log_packet(PKT_INCOMING, pktin.type, ssh2_pkt_type(pktin.type),
959 pktin.data+6, pktin.length-6);
961 switch (pktin.type) {
963 * These packets we must handle instantly.
965 case SSH2_MSG_DISCONNECT:
967 /* log reason code in disconnect message */
969 int reason = GET_32BIT(pktin.data + 6);
970 unsigned msglen = GET_32BIT(pktin.data + 10);
972 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
973 sprintf(buf, "Received disconnect message (%s)",
974 ssh2_disconnect_reasons[reason]);
976 sprintf(buf, "Received disconnect message (unknown type %d)",
980 strcpy(buf, "Disconnection message text: ");
981 nowlen = strlen(buf);
982 if (msglen > sizeof(buf) - nowlen - 1)
983 msglen = sizeof(buf) - nowlen - 1;
984 memcpy(buf + nowlen, pktin.data + 14, msglen);
985 buf[nowlen + msglen] = '\0';
987 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
989 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
990 ssh2_disconnect_reasons[reason] : "unknown",
995 case SSH2_MSG_IGNORE:
999 /* log the debug message */
1001 /* int display = pktin.body[6]; */
1002 int stringlen = GET_32BIT(pktin.data+7);
1004 strcpy(buf, "Remote debug message: ");
1005 prefix = strlen(buf);
1006 if (stringlen > sizeof(buf)-prefix-1)
1007 stringlen = sizeof(buf)-prefix-1;
1008 memcpy(buf + prefix, pktin.data + 11, stringlen);
1009 buf[prefix + stringlen] = '\0';
1012 goto next_packet; /* FIXME: print the debug message */
1015 * These packets we need do nothing about here.
1017 case SSH2_MSG_UNIMPLEMENTED:
1018 case SSH2_MSG_SERVICE_REQUEST:
1019 case SSH2_MSG_SERVICE_ACCEPT:
1020 case SSH2_MSG_KEXINIT:
1021 case SSH2_MSG_NEWKEYS:
1022 case SSH2_MSG_KEXDH_INIT:
1023 case SSH2_MSG_KEXDH_REPLY:
1024 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1025 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1026 case SSH2_MSG_KEX_DH_GEX_INIT:
1027 case SSH2_MSG_KEX_DH_GEX_REPLY:
1028 case SSH2_MSG_USERAUTH_REQUEST:
1029 case SSH2_MSG_USERAUTH_FAILURE:
1030 case SSH2_MSG_USERAUTH_SUCCESS:
1031 case SSH2_MSG_USERAUTH_BANNER:
1032 case SSH2_MSG_USERAUTH_PK_OK:
1033 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1034 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1035 case SSH2_MSG_USERAUTH_INFO_RESPONSE:
1036 case SSH2_MSG_GLOBAL_REQUEST:
1037 case SSH2_MSG_REQUEST_SUCCESS:
1038 case SSH2_MSG_REQUEST_FAILURE:
1039 case SSH2_MSG_CHANNEL_OPEN:
1040 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
1041 case SSH2_MSG_CHANNEL_OPEN_FAILURE:
1042 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1043 case SSH2_MSG_CHANNEL_DATA:
1044 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1045 case SSH2_MSG_CHANNEL_EOF:
1046 case SSH2_MSG_CHANNEL_CLOSE:
1047 case SSH2_MSG_CHANNEL_REQUEST:
1048 case SSH2_MSG_CHANNEL_SUCCESS:
1049 case SSH2_MSG_CHANNEL_FAILURE:
1053 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1056 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
1057 ssh2_pkt_adduint32(st->incoming_sequence - 1);
1065 static void ssh1_pktout_size(int len)
1069 len += 5; /* type and CRC */
1070 pad = 8 - (len % 8);
1073 pktout.length = len - 5;
1074 if (pktout.maxlen < biglen) {
1075 pktout.maxlen = biglen;
1077 /* Allocate enough buffer space for extra block
1078 * for MS CryptEncrypt() */
1079 pktout.data = (pktout.data == NULL ? smalloc(biglen + 12) :
1080 srealloc(pktout.data, biglen + 12));
1082 pktout.data = (pktout.data == NULL ? smalloc(biglen + 4) :
1083 srealloc(pktout.data, biglen + 4));
1086 fatalbox("Out of memory");
1088 pktout.body = pktout.data + 4 + pad + 1;
1091 static void s_wrpkt_start(int type, int len)
1093 ssh1_pktout_size(len);
1097 static int s_wrpkt_prepare(void)
1099 int pad, len, biglen, i;
1102 pktout.body[-1] = pktout.type;
1104 log_packet(PKT_OUTGOING, pktout.type, ssh1_pkt_type(pktout.type),
1105 pktout.body, pktout.length);
1107 if (ssh1_compressing) {
1108 unsigned char *compblk;
1110 zlib_compress_block(pktout.body - 1, pktout.length + 1,
1111 &compblk, &complen);
1112 ssh1_pktout_size(complen - 1);
1113 memcpy(pktout.body - 1, compblk, complen);
1117 len = pktout.length + 5; /* type and CRC */
1118 pad = 8 - (len % 8);
1121 for (i = 0; i < pad; i++)
1122 pktout.data[i + 4] = random_byte();
1123 crc = crc32(pktout.data + 4, biglen - 4);
1124 PUT_32BIT(pktout.data + biglen, crc);
1125 PUT_32BIT(pktout.data, len);
1128 cipher->encrypt(pktout.data + 4, biglen);
1133 static void s_wrpkt(void)
1136 len = s_wrpkt_prepare();
1137 backlog = sk_write(s, pktout.data, len);
1138 if (backlog > SSH_MAX_BACKLOG)
1139 ssh_throttle_all(1, backlog);
1142 static void s_wrpkt_defer(void)
1145 len = s_wrpkt_prepare();
1146 if (deferred_len + len > deferred_size) {
1147 deferred_size = deferred_len + len + 128;
1148 deferred_send_data = srealloc(deferred_send_data, deferred_size);
1150 memcpy(deferred_send_data + deferred_len, pktout.data, len);
1151 deferred_len += len;
1155 * Construct a packet with the specified contents.
1157 static void construct_packet(int pkttype, va_list ap1, va_list ap2)
1159 unsigned char *p, *argp, argchar;
1160 unsigned long argint;
1161 int pktlen, argtype, arglen;
1165 while ((argtype = va_arg(ap1, int)) != PKT_END) {
1168 (void) va_arg(ap1, int);
1172 (void) va_arg(ap1, char);
1176 (void) va_arg(ap1, unsigned char *);
1177 arglen = va_arg(ap1, int);
1181 argp = va_arg(ap1, unsigned char *);
1182 arglen = strlen(argp);
1183 pktlen += 4 + arglen;
1186 bn = va_arg(ap1, Bignum);
1187 pktlen += ssh1_bignum_length(bn);
1194 s_wrpkt_start(pkttype, pktlen);
1197 while ((argtype = va_arg(ap2, int)) != PKT_END) {
1200 argint = va_arg(ap2, int);
1201 PUT_32BIT(p, argint);
1205 argchar = va_arg(ap2, unsigned char);
1210 argp = va_arg(ap2, unsigned char *);
1211 arglen = va_arg(ap2, int);
1212 memcpy(p, argp, arglen);
1216 argp = va_arg(ap2, unsigned char *);
1217 arglen = strlen(argp);
1218 PUT_32BIT(p, arglen);
1219 memcpy(p + 4, argp, arglen);
1223 bn = va_arg(ap2, Bignum);
1224 p += ssh1_write_bignum(p, bn);
1230 static void send_packet(int pkttype, ...)
1233 va_start(ap1, pkttype);
1234 va_start(ap2, pkttype);
1235 construct_packet(pkttype, ap1, ap2);
1239 static void defer_packet(int pkttype, ...)
1242 va_start(ap1, pkttype);
1243 va_start(ap2, pkttype);
1244 construct_packet(pkttype, ap1, ap2);
1248 static int ssh_versioncmp(char *a, char *b)
1251 unsigned long av, bv;
1253 av = strtoul(a, &ae, 10);
1254 bv = strtoul(b, &be, 10);
1256 return (av < bv ? -1 : +1);
1261 av = strtoul(ae, &ae, 10);
1262 bv = strtoul(be, &be, 10);
1264 return (av < bv ? -1 : +1);
1270 * Utility routines for putting an SSH-protocol `string' and
1271 * `uint32' into a SHA state.
1274 static void sha_string(SHA_State * s, void *str, int len)
1276 unsigned char lenblk[4];
1277 PUT_32BIT(lenblk, len);
1278 SHA_Bytes(s, lenblk, 4);
1279 SHA_Bytes(s, str, len);
1282 static void sha_uint32(SHA_State * s, unsigned i)
1284 unsigned char intblk[4];
1285 PUT_32BIT(intblk, i);
1286 SHA_Bytes(s, intblk, 4);
1290 * SSH2 packet construction functions.
1292 static void ssh2_pkt_ensure(int length)
1294 if (pktout.maxlen < length) {
1295 pktout.maxlen = length + 256;
1298 NULL ? smalloc(pktout.maxlen +
1299 APIEXTRA) : srealloc(pktout.data,
1303 fatalbox("Out of memory");
1306 static void ssh2_pkt_adddata(void *data, int len)
1308 pktout.length += len;
1309 ssh2_pkt_ensure(pktout.length);
1310 memcpy(pktout.data + pktout.length - len, data, len);
1312 static void ssh2_pkt_addbyte(unsigned char byte)
1314 ssh2_pkt_adddata(&byte, 1);
1316 static void ssh2_pkt_init(int pkt_type)
1319 ssh2_pkt_addbyte((unsigned char) pkt_type);
1321 static void ssh2_pkt_addbool(unsigned char value)
1323 ssh2_pkt_adddata(&value, 1);
1325 static void ssh2_pkt_adduint32(unsigned long value)
1328 PUT_32BIT(x, value);
1329 ssh2_pkt_adddata(x, 4);
1331 static void ssh2_pkt_addstring_start(void)
1333 ssh2_pkt_adduint32(0);
1334 pktout.savedpos = pktout.length;
1336 static void ssh2_pkt_addstring_str(char *data)
1338 ssh2_pkt_adddata(data, strlen(data));
1339 PUT_32BIT(pktout.data + pktout.savedpos - 4,
1340 pktout.length - pktout.savedpos);
1342 static void ssh2_pkt_addstring_data(char *data, int len)
1344 ssh2_pkt_adddata(data, len);
1345 PUT_32BIT(pktout.data + pktout.savedpos - 4,
1346 pktout.length - pktout.savedpos);
1348 static void ssh2_pkt_addstring(char *data)
1350 ssh2_pkt_addstring_start();
1351 ssh2_pkt_addstring_str(data);
1353 static char *ssh2_mpint_fmt(Bignum b, int *len)
1356 int i, n = (bignum_bitcount(b) + 7) / 8;
1359 fatalbox("out of memory");
1361 for (i = 1; i <= n; i++)
1362 p[i] = bignum_byte(b, n - i);
1364 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1366 memmove(p, p + i, n + 1 - i);
1370 static void ssh2_pkt_addmp(Bignum b)
1374 p = ssh2_mpint_fmt(b, &len);
1375 ssh2_pkt_addstring_start();
1376 ssh2_pkt_addstring_data(p, len);
1381 * Construct an SSH2 final-form packet: compress it, encrypt it,
1382 * put the MAC on it. Final packet, ready to be sent, is stored in
1383 * pktout.data. Total length is returned.
1385 static int ssh2_pkt_construct(void)
1387 int cipherblk, maclen, padding, i;
1388 static unsigned long outgoing_sequence = 0;
1390 log_packet(PKT_OUTGOING, pktout.data[5], ssh2_pkt_type(pktout.data[5]),
1391 pktout.data + 6, pktout.length - 6);
1394 * Compress packet payload.
1397 unsigned char *newpayload;
1399 if (cscomp && cscomp->compress(pktout.data + 5, pktout.length - 5,
1400 &newpayload, &newlen)) {
1402 ssh2_pkt_adddata(newpayload, newlen);
1408 * Add padding. At least four bytes, and must also bring total
1409 * length (minus MAC) up to a multiple of the block size.
1411 cipherblk = cscipher ? cscipher->blksize : 8; /* block size */
1412 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
1415 (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
1416 maclen = csmac ? csmac->len : 0;
1417 ssh2_pkt_ensure(pktout.length + padding + maclen);
1418 pktout.data[4] = padding;
1419 for (i = 0; i < padding; i++)
1420 pktout.data[pktout.length + i] = random_byte();
1421 PUT_32BIT(pktout.data, pktout.length + padding - 4);
1423 csmac->generate(pktout.data, pktout.length + padding,
1425 outgoing_sequence++; /* whether or not we MACed */
1428 cscipher->encrypt(pktout.data, pktout.length + padding);
1430 /* Ready-to-send packet starts at pktout.data. We return length. */
1431 return pktout.length + padding + maclen;
1435 * Construct and send an SSH2 packet immediately.
1437 static void ssh2_pkt_send(void)
1441 len = ssh2_pkt_construct();
1442 backlog = sk_write(s, pktout.data, len);
1443 if (backlog > SSH_MAX_BACKLOG)
1444 ssh_throttle_all(1, backlog);
1448 * Construct an SSH2 packet and add it to a deferred data block.
1449 * Useful for sending multiple packets in a single sk_write() call,
1450 * to prevent a traffic-analysing listener from being able to work
1451 * out the length of any particular packet (such as the password
1454 * Note that because SSH2 sequence-numbers its packets, this can
1455 * NOT be used as an m4-style `defer' allowing packets to be
1456 * constructed in one order and sent in another.
1458 static void ssh2_pkt_defer(void)
1460 int len = ssh2_pkt_construct();
1461 if (deferred_len + len > deferred_size) {
1462 deferred_size = deferred_len + len + 128;
1463 deferred_send_data = srealloc(deferred_send_data, deferred_size);
1465 memcpy(deferred_send_data + deferred_len, pktout.data, len);
1466 deferred_len += len;
1470 * Send the whole deferred data block constructed by
1471 * ssh2_pkt_defer() or SSH1's defer_packet().
1473 static void ssh_pkt_defersend(void)
1476 backlog = sk_write(s, deferred_send_data, deferred_len);
1477 deferred_len = deferred_size = 0;
1478 sfree(deferred_send_data);
1479 deferred_send_data = NULL;
1480 if (backlog > SSH_MAX_BACKLOG)
1481 ssh_throttle_all(1, backlog);
1485 void bndebug(char *string, Bignum b)
1489 p = ssh2_mpint_fmt(b, &len);
1490 debug(("%s", string));
1491 for (i = 0; i < len; i++)
1492 debug((" %02x", p[i]));
1498 static void sha_mpint(SHA_State * s, Bignum b)
1502 p = ssh2_mpint_fmt(b, &len);
1503 sha_string(s, p, len);
1508 * SSH2 packet decode functions.
1510 static unsigned long ssh2_pkt_getuint32(void)
1512 unsigned long value;
1513 if (pktin.length - pktin.savedpos < 4)
1514 return 0; /* arrgh, no way to decline (FIXME?) */
1515 value = GET_32BIT(pktin.data + pktin.savedpos);
1516 pktin.savedpos += 4;
1519 static int ssh2_pkt_getbool(void)
1521 unsigned long value;
1522 if (pktin.length - pktin.savedpos < 1)
1523 return 0; /* arrgh, no way to decline (FIXME?) */
1524 value = pktin.data[pktin.savedpos] != 0;
1528 static void ssh2_pkt_getstring(char **p, int *length)
1531 if (pktin.length - pktin.savedpos < 4)
1533 *length = GET_32BIT(pktin.data + pktin.savedpos);
1534 pktin.savedpos += 4;
1535 if (pktin.length - pktin.savedpos < *length)
1537 *p = pktin.data + pktin.savedpos;
1538 pktin.savedpos += *length;
1540 static Bignum ssh2_pkt_getmp(void)
1546 ssh2_pkt_getstring(&p, &length);
1550 bombout(("internal error: Can't handle negative mpints"));
1553 b = bignum_from_bytes(p, length);
1558 * Examine the remote side's version string and compare it against
1559 * a list of known buggy implementations.
1561 static void ssh_detect_bugs(char *vstring)
1563 char *imp; /* pointer to implementation part */
1565 imp += strcspn(imp, "-");
1567 imp += strcspn(imp, "-");
1570 ssh_remote_bugs = 0;
1572 if (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
1573 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
1574 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25")) {
1576 * These versions don't support SSH1_MSG_IGNORE, so we have
1577 * to use a different defence against password length
1580 ssh_remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
1581 logevent("We believe remote version has SSH1 ignore bug");
1584 if (!strcmp(imp, "Cisco-1.25")) {
1586 * These versions need a plain password sent; they can't
1587 * handle having a null and a random length of data after
1590 ssh_remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
1591 logevent("We believe remote version needs a plain SSH1 password");
1594 if (!strcmp(imp, "Cisco-1.25")) {
1596 * These versions apparently have no clue whatever about
1597 * RSA authentication and will panic and die if they see
1598 * an AUTH_RSA message.
1600 ssh_remote_bugs |= BUG_CHOKES_ON_RSA;
1601 logevent("We believe remote version can't handle RSA authentication");
1604 if (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) ||
1605 !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) ||
1606 !strncmp(imp, "2.1 ", 4)) {
1608 * These versions have the HMAC bug.
1610 ssh_remote_bugs |= BUG_SSH2_HMAC;
1611 logevent("We believe remote version has SSH2 HMAC bug");
1615 static int do_ssh_init(unsigned char c)
1618 static char version[10];
1619 static char *vstring;
1620 static int vstrsize;
1626 /* Search for the string "SSH-" in the input. */
1629 static const int transS[] = { 1, 2, 2, 1 };
1630 static const int transH[] = { 0, 0, 3, 0 };
1631 static const int transminus[] = { 0, 0, 0, -1 };
1642 crReturn(1); /* get another character */
1646 vstring = smalloc(vstrsize);
1647 strcpy(vstring, "SSH-");
1651 crReturn(1); /* get another char */
1652 if (vslen >= vstrsize - 1) {
1654 vstring = srealloc(vstring, vstrsize);
1656 vstring[vslen++] = c;
1661 } else if (i < sizeof(version) - 1)
1663 } else if (c == '\n')
1667 ssh_agentfwd_enabled = FALSE;
1668 rdpkt2_state.incoming_sequence = 0;
1671 vlog = smalloc(20 + vslen);
1672 vstring[strcspn (vstring, "\r\n")] = '\0'; /* remove end-of-line chars */
1673 sprintf(vlog, "Server version: %s", vstring);
1675 ssh_detect_bugs(vstring);
1679 * Server version "1.99" means we can choose whether we use v1
1680 * or v2 protocol. Choice is based on cfg.sshprot.
1682 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
1684 * This is a v2 server. Begin v2 protocol.
1686 char verstring[80], vlog[100];
1687 sprintf(verstring, "SSH-2.0-%s", sshver);
1688 SHA_Init(&exhashbase);
1690 * Hash our version string and their version string.
1692 sha_string(&exhashbase, verstring, strlen(verstring));
1693 sha_string(&exhashbase, vstring, strcspn(vstring, "\r\n"));
1694 sprintf(vlog, "We claim version: %s", verstring);
1696 strcat(verstring, "\n");
1697 logevent("Using SSH protocol version 2");
1698 sk_write(s, verstring, strlen(verstring));
1699 ssh_protocol = ssh2_protocol;
1701 s_rdpkt = ssh2_rdpkt;
1704 * This is a v1 server. Begin v1 protocol.
1706 char verstring[80], vlog[100];
1707 sprintf(verstring, "SSH-%s-%s",
1708 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"),
1710 sprintf(vlog, "We claim version: %s", verstring);
1712 strcat(verstring, "\n");
1713 logevent("Using SSH protocol version 1");
1714 sk_write(s, verstring, strlen(verstring));
1715 ssh_protocol = ssh1_protocol;
1717 s_rdpkt = ssh1_rdpkt;
1719 ssh_state = SSH_STATE_BEFORE_SIZE;
1726 static void ssh_gotdata(unsigned char *data, int datalen)
1731 * To begin with, feed the characters one by one to the
1732 * protocol initialisation / selection function do_ssh_init().
1733 * When that returns 0, we're done with the initial greeting
1734 * exchange and can move on to packet discipline.
1739 crReturnV; /* more data please */
1740 ret = do_ssh_init(*data);
1748 * We emerge from that loop when the initial negotiation is
1749 * over and we have selected an s_rdpkt function. Now pass
1750 * everything to s_rdpkt, and then pass the resulting packets
1751 * to the proper protocol handler.
1756 while (datalen > 0) {
1757 if (s_rdpkt(&data, &datalen) == 0) {
1758 if (ssh_state == SSH_STATE_CLOSED) {
1761 ssh_protocol(NULL, 0, 1);
1762 if (ssh_state == SSH_STATE_CLOSED) {
1772 static int ssh_closing(Plug plug, char *error_msg, int error_code,
1775 ssh_state = SSH_STATE_CLOSED;
1781 /* A socket error has occurred. */
1782 connection_fatal(error_msg);
1784 /* Otherwise, the remote side closed the connection normally. */
1789 static int ssh_receive(Plug plug, int urgent, char *data, int len)
1791 ssh_gotdata(data, len);
1792 if (ssh_state == SSH_STATE_CLOSED) {
1802 static void ssh_sent(Plug plug, int bufsize)
1805 * If the send backlog on the SSH socket itself clears, we
1806 * should unthrottle the whole world if it was throttled.
1808 if (bufsize < SSH_MAX_BACKLOG)
1809 ssh_throttle_all(0, bufsize);
1813 * Connect to specified host and port.
1814 * Returns an error message, or NULL on success.
1815 * Also places the canonical host name into `realhost'. It must be
1816 * freed by the caller.
1818 static char *connect_to_host(char *host, int port, char **realhost, int nodelay)
1820 static struct plug_function_table fn_table = {
1825 }, *fn_table_ptr = &fn_table;
1834 savedhost = smalloc(1 + strlen(host));
1836 fatalbox("Out of memory");
1837 strcpy(savedhost, host);
1840 port = 22; /* default ssh port */
1855 sprintf(buf, "Looking up host \"%.170s\"", host);
1858 addr = sk_namelookup(host, realhost);
1859 if ((err = sk_addr_error(addr)))
1863 *realhost = strdup(FWhost);
1870 char buf[200], addrbuf[100];
1871 sk_getaddr(addr, addrbuf, 100);
1872 sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
1875 s = sk_new(addr, port, 0, 1, nodelay, &fn_table_ptr);
1876 if ((err = sk_socket_error(s))) {
1882 sk_write(s, "connect ", 8);
1883 sk_write(s, FWhost, strlen(FWhost));
1886 sprintf(buf, " %d\n", FWport);
1887 sk_write(s, buf, strlen(buf));
1895 * Throttle or unthrottle the SSH connection.
1897 static void ssh1_throttle(int adjust)
1899 int old_count = ssh1_throttle_count;
1900 ssh1_throttle_count += adjust;
1901 assert(ssh1_throttle_count >= 0);
1902 if (ssh1_throttle_count && !old_count) {
1903 sk_set_frozen(s, 1);
1904 } else if (!ssh1_throttle_count && old_count) {
1905 sk_set_frozen(s, 0);
1910 * Throttle or unthrottle _all_ local data streams (for when sends
1911 * on the SSH connection itself back up).
1913 static void ssh_throttle_all(int enable, int bufsize)
1916 struct ssh_channel *c;
1918 if (enable == ssh_throttled_all)
1920 ssh_throttled_all = enable;
1921 ssh_overall_bufsize = bufsize;
1924 for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
1926 case CHAN_MAINSESSION:
1928 * This is treated separately, outside the switch.
1932 x11_override_throttle(c->u.x11.s, enable);
1935 /* Agent channels require no buffer management. */
1938 pfd_override_throttle(c->u.x11.s, enable);
1945 * Handle the key exchange and user authentication phases.
1947 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1951 static unsigned char *rsabuf, *keystr1, *keystr2;
1952 unsigned char cookie[8];
1953 struct RSAKey servkey, hostkey;
1954 struct MD5Context md5c;
1955 static unsigned long supported_ciphers_mask, supported_auths_mask;
1956 static int tried_publickey, tried_agent;
1957 static int tis_auth_refused, ccard_auth_refused;
1958 static unsigned char session_id[16];
1959 static int cipher_type;
1960 static char username[100];
1961 static void *publickey_blob;
1962 int publickey_bloblen;
1969 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1970 bombout(("Public key packet not received"));
1974 logevent("Received public keys");
1976 memcpy(cookie, pktin.body, 8);
1978 i = makekey(pktin.body + 8, &servkey, &keystr1, 0);
1979 j = makekey(pktin.body + 8 + i, &hostkey, &keystr2, 0);
1982 * Log the host key fingerprint.
1986 logevent("Host key fingerprint is:");
1987 strcpy(logmsg, " ");
1988 hostkey.comment = NULL;
1989 rsa_fingerprint(logmsg + strlen(logmsg),
1990 sizeof(logmsg) - strlen(logmsg), &hostkey);
1994 ssh1_remote_protoflags = GET_32BIT(pktin.body + 8 + i + j);
1995 supported_ciphers_mask = GET_32BIT(pktin.body + 12 + i + j);
1996 supported_auths_mask = GET_32BIT(pktin.body + 16 + i + j);
1998 ssh1_local_protoflags =
1999 ssh1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2000 ssh1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
2003 MD5Update(&md5c, keystr2, hostkey.bytes);
2004 MD5Update(&md5c, keystr1, servkey.bytes);
2005 MD5Update(&md5c, pktin.body, 8);
2006 MD5Final(session_id, &md5c);
2008 for (i = 0; i < 32; i++)
2009 session_key[i] = random_byte();
2011 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
2013 rsabuf = smalloc(len);
2015 fatalbox("Out of memory");
2018 * Verify the host key.
2022 * First format the key into a string.
2024 int len = rsastr_len(&hostkey);
2025 char fingerprint[100];
2026 char *keystr = smalloc(len);
2028 fatalbox("Out of memory");
2029 rsastr_fmt(keystr, &hostkey);
2030 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
2031 verify_ssh_host_key(savedhost, savedport, "rsa", keystr,
2036 for (i = 0; i < 32; i++) {
2037 rsabuf[i] = session_key[i];
2039 rsabuf[i] ^= session_id[i];
2042 if (hostkey.bytes > servkey.bytes) {
2043 rsaencrypt(rsabuf, 32, &servkey);
2044 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
2046 rsaencrypt(rsabuf, 32, &hostkey);
2047 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
2050 logevent("Encrypted session key");
2053 int cipher_chosen = 0, warn = 0;
2054 char *cipher_string = NULL;
2055 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
2056 int next_cipher = cfg.ssh_cipherlist[i];
2057 if (next_cipher == CIPHER_WARN) {
2058 /* If/when we choose a cipher, warn about it */
2060 } else if (next_cipher == CIPHER_AES) {
2061 /* XXX Probably don't need to mention this. */
2062 logevent("AES not supported in SSH1, skipping");
2064 switch (next_cipher) {
2065 case CIPHER_3DES: cipher_type = SSH_CIPHER_3DES;
2066 cipher_string = "3DES"; break;
2067 case CIPHER_BLOWFISH: cipher_type = SSH_CIPHER_BLOWFISH;
2068 cipher_string = "Blowfish"; break;
2069 case CIPHER_DES: cipher_type = SSH_CIPHER_DES;
2070 cipher_string = "single-DES"; break;
2072 if (supported_ciphers_mask & (1 << cipher_type))
2076 if (!cipher_chosen) {
2077 if ((supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
2078 bombout(("Server violates SSH 1 protocol by not "
2079 "supporting 3DES encryption"));
2081 /* shouldn't happen */
2082 bombout(("No supported ciphers found"));
2086 /* Warn about chosen cipher if necessary. */
2088 askcipher(cipher_string, 0);
2091 switch (cipher_type) {
2092 case SSH_CIPHER_3DES:
2093 logevent("Using 3DES encryption");
2095 case SSH_CIPHER_DES:
2096 logevent("Using single-DES encryption");
2098 case SSH_CIPHER_BLOWFISH:
2099 logevent("Using Blowfish encryption");
2103 send_packet(SSH1_CMSG_SESSION_KEY,
2104 PKT_CHAR, cipher_type,
2105 PKT_DATA, cookie, 8,
2106 PKT_CHAR, (len * 8) >> 8, PKT_CHAR, (len * 8) & 0xFF,
2107 PKT_DATA, rsabuf, len,
2108 PKT_INT, ssh1_local_protoflags, PKT_END);
2110 logevent("Trying to enable encryption...");
2114 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2115 cipher_type == SSH_CIPHER_DES ? &ssh_des : &ssh_3des;
2116 cipher->sesskey(session_key);
2120 if (pktin.type != SSH1_SMSG_SUCCESS) {
2121 bombout(("Encryption not successfully enabled"));
2125 logevent("Successfully started encryption");
2131 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2133 if (!ssh_get_line("login as: ",
2134 username, sizeof(username), FALSE)) {
2136 * get_line failed to get a username.
2139 logevent("No username provided. Abandoning session.");
2140 ssh_state = SSH_STATE_CLOSED;
2144 c_write_str("login as: ");
2147 crWaitUntil(!ispkt);
2149 switch (c = *in++) {
2158 c_write_str("\b \b");
2165 c_write_str("\b \b");
2175 if (((c >= ' ' && c <= '~') ||
2176 ((unsigned char) c >= 160))
2177 && pos < sizeof(username)-1) {
2178 username[pos++] = c;
2184 c_write_str("\r\n");
2185 username[strcspn(username, "\n\r")] = '\0';
2188 strncpy(username, cfg.username, 99);
2189 username[99] = '\0';
2192 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
2194 char userlog[22 + sizeof(username)];
2195 sprintf(userlog, "Sent username \"%s\"", username);
2197 if (flags & FLAG_INTERACTIVE &&
2198 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
2199 strcat(userlog, "\r\n");
2200 c_write_str(userlog);
2207 if ((ssh_remote_bugs & BUG_CHOKES_ON_RSA)) {
2208 /* We must not attempt PK auth. Pretend we've already tried it. */
2209 tried_publickey = tried_agent = 1;
2211 tried_publickey = tried_agent = 0;
2213 tis_auth_refused = ccard_auth_refused = 0;
2214 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2216 if (!rsakey_pubblob(cfg.keyfile, &publickey_blob, &publickey_bloblen))
2217 publickey_blob = NULL;
2219 publickey_blob = NULL;
2221 while (pktin.type == SSH1_SMSG_FAILURE) {
2222 static char password[100];
2223 static char prompt[200];
2226 static int pwpkt_type;
2227 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
2229 if (agent_exists() && !tried_agent) {
2231 * Attempt RSA authentication using Pageant.
2233 static unsigned char request[5], *response, *p;
2234 static int responselen;
2235 static int i, nkeys;
2236 static int authed = FALSE;
2240 logevent("Pageant is running. Requesting keys.");
2242 /* Request the keys held by the agent. */
2243 PUT_32BIT(request, 1);
2244 request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
2245 agent_query(request, 5, &r, &responselen);
2246 response = (unsigned char *) r;
2247 if (response && responselen >= 5 &&
2248 response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2250 nkeys = GET_32BIT(p);
2254 sprintf(buf, "Pageant has %d SSH1 keys", nkeys);
2257 for (i = 0; i < nkeys; i++) {
2258 static struct RSAKey key;
2259 static Bignum challenge;
2260 static char *commentp;
2261 static int commentlen;
2265 sprintf(buf, "Trying Pageant key #%d", i);
2268 if (publickey_blob &&
2269 !memcmp(p, publickey_blob, publickey_bloblen)) {
2270 logevent("This key matches configured key file");
2271 tried_publickey = 1;
2274 p += ssh1_read_bignum(p, &key.exponent);
2275 p += ssh1_read_bignum(p, &key.modulus);
2276 commentlen = GET_32BIT(p);
2280 send_packet(SSH1_CMSG_AUTH_RSA,
2281 PKT_BIGNUM, key.modulus, PKT_END);
2283 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
2284 logevent("Key refused");
2287 logevent("Received RSA challenge");
2288 ssh1_read_bignum(pktin.body, &challenge);
2290 char *agentreq, *q, *ret;
2293 len = 1 + 4; /* message type, bit count */
2294 len += ssh1_bignum_length(key.exponent);
2295 len += ssh1_bignum_length(key.modulus);
2296 len += ssh1_bignum_length(challenge);
2297 len += 16; /* session id */
2298 len += 4; /* response format */
2299 agentreq = smalloc(4 + len);
2300 PUT_32BIT(agentreq, len);
2302 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
2303 PUT_32BIT(q, bignum_bitcount(key.modulus));
2305 q += ssh1_write_bignum(q, key.exponent);
2306 q += ssh1_write_bignum(q, key.modulus);
2307 q += ssh1_write_bignum(q, challenge);
2308 memcpy(q, session_id, 16);
2310 PUT_32BIT(q, 1); /* response format */
2311 agent_query(agentreq, len + 4, &vret, &retlen);
2315 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2316 logevent("Sending Pageant's response");
2317 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
2318 PKT_DATA, ret + 5, 16,
2322 if (pktin.type == SSH1_SMSG_SUCCESS) {
2324 ("Pageant's response accepted");
2325 if (flags & FLAG_VERBOSE) {
2327 ("Authenticated using RSA key \"");
2328 c_write(commentp, commentlen);
2329 c_write_str("\" from agent\r\n");
2334 ("Pageant's response not accepted");
2337 ("Pageant failed to answer challenge");
2341 logevent("No reply received from Pageant");
2344 freebn(key.exponent);
2345 freebn(key.modulus);
2354 if (*cfg.keyfile && !tried_publickey)
2355 pwpkt_type = SSH1_CMSG_AUTH_RSA;
2357 if (cfg.try_tis_auth &&
2358 (supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2359 !tis_auth_refused) {
2360 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
2361 logevent("Requested TIS authentication");
2362 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
2364 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
2365 logevent("TIS authentication declined");
2366 if (flags & FLAG_INTERACTIVE)
2367 c_write_str("TIS authentication refused.\r\n");
2368 tis_auth_refused = 1;
2371 int challengelen = ((pktin.body[0] << 24) |
2372 (pktin.body[1] << 16) |
2373 (pktin.body[2] << 8) |
2375 logevent("Received TIS challenge");
2376 if (challengelen > sizeof(prompt) - 1)
2377 challengelen = sizeof(prompt) - 1; /* prevent overrun */
2378 memcpy(prompt, pktin.body + 4, challengelen);
2379 /* Prompt heuristic comes from OpenSSH */
2380 strncpy(prompt + challengelen,
2381 memchr(prompt, '\n', challengelen) ?
2382 "": "\r\nResponse: ",
2383 (sizeof prompt) - challengelen);
2384 prompt[(sizeof prompt) - 1] = '\0';
2387 if (cfg.try_tis_auth &&
2388 (supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
2389 !ccard_auth_refused) {
2390 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
2391 logevent("Requested CryptoCard authentication");
2392 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
2394 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
2395 logevent("CryptoCard authentication declined");
2396 c_write_str("CryptoCard authentication refused.\r\n");
2397 ccard_auth_refused = 1;
2400 int challengelen = ((pktin.body[0] << 24) |
2401 (pktin.body[1] << 16) |
2402 (pktin.body[2] << 8) |
2404 logevent("Received CryptoCard challenge");
2405 if (challengelen > sizeof(prompt) - 1)
2406 challengelen = sizeof(prompt) - 1; /* prevent overrun */
2407 memcpy(prompt, pktin.body + 4, challengelen);
2408 strncpy(prompt + challengelen,
2409 memchr(prompt, '\n', challengelen) ?
2410 "" : "\r\nResponse: ",
2411 sizeof(prompt) - challengelen);
2412 prompt[sizeof(prompt) - 1] = '\0';
2415 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2416 sprintf(prompt, "%.90s@%.90s's password: ",
2417 username, savedhost);
2419 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
2420 char *comment = NULL;
2421 if (flags & FLAG_VERBOSE)
2422 c_write_str("Trying public key authentication.\r\n");
2423 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
2424 if (flags & FLAG_VERBOSE)
2425 c_write_str("No passphrase required.\r\n");
2428 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
2433 * Show password prompt, having first obtained it via a TIS
2434 * or CryptoCard exchange if we're doing TIS or CryptoCard
2438 if (!ssh_get_line(prompt, password, sizeof(password), TRUE)) {
2440 * get_line failed to get a password (for example
2441 * because one was supplied on the command line
2442 * which has already failed to work). Terminate.
2444 send_packet(SSH1_MSG_DISCONNECT,
2445 PKT_STR, "No more passwords available to try",
2447 connection_fatal("Unable to authenticate");
2448 ssh_state = SSH_STATE_CLOSED;
2452 /* Prompt may have come from server. We've munged it a bit, so
2453 * we know it to be zero-terminated at least once. */
2454 c_write_untrusted(prompt, strlen(prompt));
2458 crWaitUntil(!ispkt);
2460 switch (c = *in++) {
2481 if (pos < sizeof(password)-1)
2482 password[pos++] = c;
2486 c_write_str("\r\n");
2490 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
2492 * Try public key authentication with the specified
2495 static struct RSAKey pubkey;
2496 static Bignum challenge, response;
2498 static unsigned char buffer[32];
2500 tried_publickey = 1;
2501 i = loadrsakey(cfg.keyfile, &pubkey, password);
2503 c_write_str("Couldn't load private key from ");
2504 c_write_str(cfg.keyfile);
2505 c_write_str(".\r\n");
2506 continue; /* go and try password */
2509 c_write_str("Wrong passphrase.\r\n");
2510 tried_publickey = 0;
2511 continue; /* try again */
2515 * Send a public key attempt.
2517 send_packet(SSH1_CMSG_AUTH_RSA,
2518 PKT_BIGNUM, pubkey.modulus, PKT_END);
2521 if (pktin.type == SSH1_SMSG_FAILURE) {
2522 c_write_str("Server refused our public key.\r\n");
2523 continue; /* go and try password */
2525 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
2526 bombout(("Bizarre response to offer of public key"));
2529 ssh1_read_bignum(pktin.body, &challenge);
2530 response = rsadecrypt(challenge, &pubkey);
2531 freebn(pubkey.private_exponent); /* burn the evidence */
2533 for (i = 0; i < 32; i++) {
2534 buffer[i] = bignum_byte(response, 31 - i);
2538 MD5Update(&md5c, buffer, 32);
2539 MD5Update(&md5c, session_id, 16);
2540 MD5Final(buffer, &md5c);
2542 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
2543 PKT_DATA, buffer, 16, PKT_END);
2546 if (pktin.type == SSH1_SMSG_FAILURE) {
2547 if (flags & FLAG_VERBOSE)
2549 ("Failed to authenticate with our public key.\r\n");
2550 continue; /* go and try password */
2551 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
2553 ("Bizarre response to RSA authentication response"));
2557 break; /* we're through! */
2559 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2561 * Defence against traffic analysis: we send a
2562 * whole bunch of packets containing strings of
2563 * different lengths. One of these strings is the
2564 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2565 * The others are all random data in
2566 * SSH1_MSG_IGNORE packets. This way a passive
2567 * listener can't tell which is the password, and
2568 * hence can't deduce the password length.
2570 * Anybody with a password length greater than 16
2571 * bytes is going to have enough entropy in their
2572 * password that a listener won't find it _that_
2573 * much help to know how long it is. So what we'll
2576 * - if password length < 16, we send 15 packets
2577 * containing string lengths 1 through 15
2579 * - otherwise, we let N be the nearest multiple
2580 * of 8 below the password length, and send 8
2581 * packets containing string lengths N through
2582 * N+7. This won't obscure the order of
2583 * magnitude of the password length, but it will
2584 * introduce a bit of extra uncertainty.
2586 * A few servers (the old 1.2.18 through 1.2.22)
2587 * can't deal with SSH1_MSG_IGNORE. For these
2588 * servers, we need an alternative defence. We make
2589 * use of the fact that the password is interpreted
2590 * as a C string: so we can append a NUL, then some
2593 * One server (a Cisco one) can deal with neither
2594 * SSH1_MSG_IGNORE _nor_ a padded password string.
2595 * For this server we are left with no defences
2596 * against password length sniffing.
2598 if (!(ssh_remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
2600 * The server can deal with SSH1_MSG_IGNORE, so
2601 * we can use the primary defence.
2603 int bottom, top, pwlen, i;
2606 pwlen = strlen(password);
2608 bottom = 0; /* zero length passwords are OK! :-) */
2611 bottom = pwlen & ~7;
2615 assert(pwlen >= bottom && pwlen <= top);
2617 randomstr = smalloc(top + 1);
2619 for (i = bottom; i <= top; i++) {
2621 defer_packet(pwpkt_type, PKT_STR, password,
2624 for (j = 0; j < i; j++) {
2626 randomstr[j] = random_byte();
2627 } while (randomstr[j] == '\0');
2629 randomstr[i] = '\0';
2630 defer_packet(SSH1_MSG_IGNORE,
2631 PKT_STR, randomstr, PKT_END);
2634 logevent("Sending password with camouflage packets");
2635 ssh_pkt_defersend();
2637 else if (!(ssh_remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
2639 * The server can't deal with SSH1_MSG_IGNORE
2640 * but can deal with padded passwords, so we
2641 * can use the secondary defence.
2647 len = strlen(password);
2648 if (len < sizeof(string)) {
2650 strcpy(string, password);
2651 len++; /* cover the zero byte */
2652 while (len < sizeof(string)) {
2653 string[len++] = (char) random_byte();
2658 logevent("Sending length-padded password");
2659 send_packet(pwpkt_type, PKT_INT, len,
2660 PKT_DATA, s, len, PKT_END);
2663 * The server has _both_
2664 * BUG_CHOKES_ON_SSH1_IGNORE and
2665 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2666 * therefore nothing we can do.
2669 len = strlen(password);
2670 logevent("Sending unpadded password");
2671 send_packet(pwpkt_type, PKT_INT, len,
2672 PKT_DATA, password, len, PKT_END);
2675 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
2678 logevent("Sent password");
2679 memset(password, 0, strlen(password));
2681 if (pktin.type == SSH1_SMSG_FAILURE) {
2682 if (flags & FLAG_VERBOSE)
2683 c_write_str("Access denied\r\n");
2684 logevent("Authentication refused");
2685 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
2686 logevent("Received disconnect request");
2687 ssh_state = SSH_STATE_CLOSED;
2689 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
2690 bombout(("Strange packet received, type %d", pktin.type));
2695 logevent("Authentication successful");
2700 void sshfwd_close(struct ssh_channel *c)
2702 if (c && !c->closes) {
2704 * If the channel's remoteid is -1, we have sent
2705 * CHANNEL_OPEN for this channel, but it hasn't even been
2706 * acknowledged by the server. So we must set a close flag
2707 * on it now, and then when the server acks the channel
2708 * open, we can close it then.
2710 if (c->remoteid != -1) {
2711 if (ssh_version == 1) {
2712 send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
2715 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2716 ssh2_pkt_adduint32(c->remoteid);
2721 if (c->type == CHAN_X11) {
2723 logevent("Forwarded X11 connection terminated");
2724 } else if (c->type == CHAN_SOCKDATA ||
2725 c->type == CHAN_SOCKDATA_DORMANT) {
2727 logevent("Forwarded port closed");
2732 int sshfwd_write(struct ssh_channel *c, char *buf, int len)
2734 if (ssh_version == 1) {
2735 send_packet(SSH1_MSG_CHANNEL_DATA,
2736 PKT_INT, c->remoteid,
2737 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
2739 * In SSH1 we can return 0 here - implying that forwarded
2740 * connections are never individually throttled - because
2741 * the only circumstance that can cause throttling will be
2742 * the whole SSH connection backing up, in which case
2743 * _everything_ will be throttled as a whole.
2747 ssh2_add_channel_data(c, buf, len);
2748 return ssh2_try_send(c);
2752 void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
2754 if (ssh_version == 1) {
2755 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
2756 c->v.v1.throttling = 0;
2760 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
2764 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
2770 while (!do_ssh1_login(in, inlen, ispkt)) {
2773 if (ssh_state == SSH_STATE_CLOSED)
2776 if (cfg.agentfwd && agent_exists()) {
2777 logevent("Requesting agent forwarding");
2778 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
2782 if (pktin.type != SSH1_SMSG_SUCCESS
2783 && pktin.type != SSH1_SMSG_FAILURE) {
2784 bombout(("Protocol confusion"));
2786 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2787 logevent("Agent forwarding refused");
2789 logevent("Agent forwarding enabled");
2790 ssh_agentfwd_enabled = TRUE;
2794 if (cfg.x11_forward) {
2795 char proto[20], data[64];
2796 logevent("Requesting X11 forwarding");
2797 x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
2798 if (ssh1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
2799 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING,
2800 PKT_STR, proto, PKT_STR, data,
2801 PKT_INT, 0, PKT_END);
2803 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING,
2804 PKT_STR, proto, PKT_STR, data, PKT_END);
2809 if (pktin.type != SSH1_SMSG_SUCCESS
2810 && pktin.type != SSH1_SMSG_FAILURE) {
2811 bombout(("Protocol confusion"));
2813 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2814 logevent("X11 forwarding refused");
2816 logevent("X11 forwarding enabled");
2817 ssh_X11_fwd_enabled = TRUE;
2825 char sports[256], dports[256], host[256];
2828 ssh_rportfwds = newtree234(ssh_rportcmp_ssh1);
2829 /* Add port forwardings. */
2834 while (*e && *e != '\t')
2840 while (*e && *e != ':')
2850 dport = atoi(dports);
2851 sport = atoi(sports);
2852 if (sport && dport) {
2854 pfd_addforward(host, dport, sport);
2855 sprintf(buf, "Local port %d forwarding to %s:%d",
2856 sport, host, dport);
2859 struct ssh_rportfwd *pf;
2860 pf = smalloc(sizeof(*pf));
2861 strcpy(pf->dhost, host);
2863 if (add234(ssh_rportfwds, pf) != pf) {
2865 "Duplicate remote port forwarding to %s:%d",
2870 sprintf(buf, "Requesting remote port %d forward to %s:%d",
2871 sport, host, dport);
2873 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST,
2885 send_packet(SSH1_CMSG_REQUEST_PTY,
2886 PKT_STR, cfg.termtype,
2887 PKT_INT, rows, PKT_INT, cols,
2888 PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END);
2889 ssh_state = SSH_STATE_INTERMED;
2893 if (pktin.type != SSH1_SMSG_SUCCESS
2894 && pktin.type != SSH1_SMSG_FAILURE) {
2895 bombout(("Protocol confusion"));
2897 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2898 c_write_str("Server refused to allocate pty\r\n");
2899 ssh_editing = ssh_echoing = 1;
2901 logevent("Allocated pty");
2903 ssh_editing = ssh_echoing = 1;
2906 if (cfg.compression) {
2907 send_packet(SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
2911 if (pktin.type != SSH1_SMSG_SUCCESS
2912 && pktin.type != SSH1_SMSG_FAILURE) {
2913 bombout(("Protocol confusion"));
2915 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2916 c_write_str("Server refused to compress\r\n");
2918 logevent("Started compression");
2919 ssh1_compressing = TRUE;
2920 zlib_compress_init();
2921 zlib_decompress_init();
2925 * Start the shell or command.
2927 * Special case: if the first-choice command is an SSH2
2928 * subsystem (hence not usable here) and the second choice
2929 * exists, we fall straight back to that.
2932 char *cmd = cfg.remote_cmd_ptr;
2934 if (cfg.ssh_subsys && cfg.remote_cmd_ptr2) {
2935 cmd = cfg.remote_cmd_ptr2;
2936 ssh_fallback_cmd = TRUE;
2939 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
2941 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
2942 logevent("Started session");
2945 ssh_state = SSH_STATE_SESSION;
2949 ssh_special(TS_EOF);
2951 ldisc_send(NULL, 0, 0); /* cause ldisc to notice changes */
2953 ssh_channels = newtree234(ssh_channelcmp);
2957 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
2958 pktin.type == SSH1_SMSG_STDERR_DATA) {
2959 long len = GET_32BIT(pktin.body);
2961 from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
2962 pktin.body + 4, len);
2963 if (!ssh1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
2964 ssh1_stdout_throttling = 1;
2967 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
2968 ssh_state = SSH_STATE_CLOSED;
2969 logevent("Received disconnect request");
2971 } else if (pktin.type == SSH1_SMSG_X11_OPEN) {
2972 /* Remote side is trying to open a channel to talk to our
2973 * X-Server. Give them back a local channel number. */
2974 struct ssh_channel *c;
2976 logevent("Received X11 connect request");
2977 /* Refuse if X11 forwarding is disabled. */
2978 if (!ssh_X11_fwd_enabled) {
2979 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
2980 PKT_INT, GET_32BIT(pktin.body), PKT_END);
2981 logevent("Rejected X11 connect request");
2983 c = smalloc(sizeof(struct ssh_channel));
2985 if (x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL) {
2986 logevent("opening X11 forward connection failed");
2988 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
2989 PKT_INT, GET_32BIT(pktin.body),
2993 ("opening X11 forward connection succeeded");
2994 c->remoteid = GET_32BIT(pktin.body);
2995 c->localid = alloc_channel_id();
2997 c->v.v1.throttling = 0;
2998 c->type = CHAN_X11; /* identify channel type */
2999 add234(ssh_channels, c);
3000 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3001 PKT_INT, c->remoteid, PKT_INT,
3002 c->localid, PKT_END);
3003 logevent("Opened X11 forward channel");
3006 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
3007 /* Remote side is trying to open a channel to talk to our
3008 * agent. Give them back a local channel number. */
3009 struct ssh_channel *c;
3011 /* Refuse if agent forwarding is disabled. */
3012 if (!ssh_agentfwd_enabled) {
3013 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
3014 PKT_INT, GET_32BIT(pktin.body), PKT_END);
3016 c = smalloc(sizeof(struct ssh_channel));
3017 c->remoteid = GET_32BIT(pktin.body);
3018 c->localid = alloc_channel_id();
3020 c->v.v1.throttling = 0;
3021 c->type = CHAN_AGENT; /* identify channel type */
3022 c->u.a.lensofar = 0;
3023 add234(ssh_channels, c);
3024 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3025 PKT_INT, c->remoteid, PKT_INT, c->localid,
3028 } else if (pktin.type == SSH1_MSG_PORT_OPEN) {
3029 /* Remote side is trying to open a channel to talk to a
3030 * forwarded port. Give them back a local channel number. */
3031 struct ssh_channel *c;
3032 struct ssh_rportfwd pf;
3034 char host[256], buf[1024];
3036 c = smalloc(sizeof(struct ssh_channel));
3038 hostsize = GET_32BIT(pktin.body+4);
3039 for(h = host, p = pktin.body+8; hostsize != 0; hostsize--) {
3040 if (h+1 < host+sizeof(host))
3045 port = GET_32BIT(p);
3047 strcpy(pf.dhost, host);
3050 if (find234(ssh_rportfwds, &pf, NULL) == NULL) {
3051 sprintf(buf, "Rejected remote port open request for %s:%d",
3054 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
3055 PKT_INT, GET_32BIT(pktin.body), PKT_END);
3057 sprintf(buf, "Received remote port open request for %s:%d",
3060 e = pfd_newconnect(&c->u.pfd.s, host, port, c);
3063 sprintf(buf, "Port open failed: %s", e);
3066 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
3067 PKT_INT, GET_32BIT(pktin.body),
3070 c->remoteid = GET_32BIT(pktin.body);
3071 c->localid = alloc_channel_id();
3073 c->v.v1.throttling = 0;
3074 c->type = CHAN_SOCKDATA; /* identify channel type */
3075 add234(ssh_channels, c);
3076 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3077 PKT_INT, c->remoteid, PKT_INT,
3078 c->localid, PKT_END);
3079 logevent("Forwarded port opened successfully");
3083 } else if (pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
3084 unsigned int remoteid = GET_32BIT(pktin.body);
3085 unsigned int localid = GET_32BIT(pktin.body+4);
3086 struct ssh_channel *c;
3088 c = find234(ssh_channels, &remoteid, ssh_channelfind);
3089 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3090 c->remoteid = localid;
3091 c->type = CHAN_SOCKDATA;
3092 c->v.v1.throttling = 0;
3093 pfd_confirm(c->u.pfd.s);
3096 if (c && c->closes) {
3098 * We have a pending close on this channel,
3099 * which we decided on before the server acked
3100 * the channel open. So now we know the
3101 * remoteid, we can close it again.
3103 send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
3107 } else if (pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
3108 unsigned int remoteid = GET_32BIT(pktin.body);
3109 unsigned int localid = GET_32BIT(pktin.body+4);
3110 struct ssh_channel *c;
3112 c = find234(ssh_channels, &remoteid, ssh_channelfind);
3113 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3114 logevent("Forwarded connection refused by server");
3115 pfd_close(c->u.pfd.s);
3116 del234(ssh_channels, c);
3120 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
3121 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
3122 /* Remote side closes a channel. */
3123 unsigned i = GET_32BIT(pktin.body);
3124 struct ssh_channel *c;
3125 c = find234(ssh_channels, &i, ssh_channelfind);
3129 (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
3130 if (!(c->closes & closetype))
3131 send_packet(pktin.type, PKT_INT, c->remoteid,
3133 if ((c->closes == 0) && (c->type == CHAN_X11)) {
3134 logevent("Forwarded X11 connection terminated");
3135 assert(c->u.x11.s != NULL);
3136 x11_close(c->u.x11.s);
3139 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3140 logevent("Forwarded port closed");
3141 assert(c->u.pfd.s != NULL);
3142 pfd_close(c->u.pfd.s);
3145 c->closes |= closetype;
3146 if (c->closes == 3) {
3147 del234(ssh_channels, c);
3151 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
3152 /* Data sent down one of our channels. */
3153 int i = GET_32BIT(pktin.body);
3154 int len = GET_32BIT(pktin.body + 4);
3155 unsigned char *p = pktin.body + 8;
3156 struct ssh_channel *c;
3157 c = find234(ssh_channels, &i, ssh_channelfind);
3162 bufsize = x11_send(c->u.x11.s, p, len);
3165 bufsize = pfd_send(c->u.pfd.s, p, len);
3168 /* Data for an agent message. Buffer it. */
3170 if (c->u.a.lensofar < 4) {
3171 int l = min(4 - c->u.a.lensofar, len);
3172 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3176 c->u.a.lensofar += l;
3178 if (c->u.a.lensofar == 4) {
3180 4 + GET_32BIT(c->u.a.msglen);
3181 c->u.a.message = smalloc(c->u.a.totallen);
3182 memcpy(c->u.a.message, c->u.a.msglen, 4);
3184 if (c->u.a.lensofar >= 4 && len > 0) {
3186 min(c->u.a.totallen - c->u.a.lensofar,
3188 memcpy(c->u.a.message + c->u.a.lensofar, p,
3192 c->u.a.lensofar += l;
3194 if (c->u.a.lensofar == c->u.a.totallen) {
3195 void *reply, *sentreply;
3197 agent_query(c->u.a.message,
3198 c->u.a.totallen, &reply,
3203 /* Fake SSH_AGENT_FAILURE. */
3204 sentreply = "\0\0\0\1\5";
3207 send_packet(SSH1_MSG_CHANNEL_DATA,
3208 PKT_INT, c->remoteid,
3210 PKT_DATA, sentreply, replylen,
3214 sfree(c->u.a.message);
3215 c->u.a.lensofar = 0;
3218 bufsize = 0; /* agent channels never back up */
3221 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
3222 c->v.v1.throttling = 1;
3226 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
3227 /* may be from EXEC_SHELL on some servers */
3228 } else if (pktin.type == SSH1_SMSG_FAILURE) {
3229 /* may be from EXEC_SHELL on some servers
3230 * if no pty is available or in other odd cases. Ignore */
3231 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
3233 ssh_exitcode = GET_32BIT(pktin.body);
3234 sprintf(buf, "Server sent command exit status %d",
3237 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
3239 * In case `helpful' firewalls or proxies tack
3240 * extra human-readable text on the end of the
3241 * session which we might mistake for another
3242 * encrypted packet, we close the session once
3243 * we've sent EXIT_CONFIRMATION.
3245 ssh_state = SSH_STATE_CLOSED;
3248 bombout(("Strange packet received: type %d", pktin.type));
3253 int len = min(inlen, 512);
3254 send_packet(SSH1_CMSG_STDIN_DATA,
3255 PKT_INT, len, PKT_DATA, in, len, PKT_END);
3266 * Utility routine for decoding comma-separated strings in KEXINIT.
3268 static int in_commasep_string(char *needle, char *haystack, int haylen)
3270 int needlen = strlen(needle);
3273 * Is it at the start of the string?
3275 if (haylen >= needlen && /* haystack is long enough */
3276 !memcmp(needle, haystack, needlen) && /* initial match */
3277 (haylen == needlen || haystack[needlen] == ',')
3278 /* either , or EOS follows */
3282 * If not, search for the next comma and resume after that.
3283 * If no comma found, terminate.
3285 while (haylen > 0 && *haystack != ',')
3286 haylen--, haystack++;
3289 haylen--, haystack++; /* skip over comma itself */
3294 * SSH2 key creation method.
3296 static void ssh2_mkkey(Bignum K, char *H, char *sessid, char chr,
3300 /* First 20 bytes. */
3303 SHA_Bytes(&s, H, 20);
3304 SHA_Bytes(&s, &chr, 1);
3305 SHA_Bytes(&s, sessid, 20);
3306 SHA_Final(&s, keyspace);
3307 /* Next 20 bytes. */
3310 SHA_Bytes(&s, H, 20);
3311 SHA_Bytes(&s, keyspace, 20);
3312 SHA_Final(&s, keyspace + 20);
3316 * Handle the SSH2 transport layer.
3318 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
3320 static int i, j, len, nbits, pbits, warn;
3322 static Bignum p, g, e, f, K;
3323 static int kex_init_value, kex_reply_value;
3324 static const struct ssh_mac **maclist;
3326 static const struct ssh2_cipher *cscipher_tobe = NULL;
3327 static const struct ssh2_cipher *sccipher_tobe = NULL;
3328 static const struct ssh_mac *csmac_tobe = NULL;
3329 static const struct ssh_mac *scmac_tobe = NULL;
3330 static const struct ssh_compress *cscomp_tobe = NULL;
3331 static const struct ssh_compress *sccomp_tobe = NULL;
3332 static char *hostkeydata, *sigdata, *keystr, *fingerprint;
3333 static int hostkeylen, siglen;
3334 static void *hkey; /* actual host key */
3335 static unsigned char exchange_hash[20];
3336 static unsigned char keyspace[40];
3337 static int n_preferred_ciphers;
3338 static const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
3339 static const struct ssh_compress *preferred_comp;
3340 static int cipherstr_started;
3341 static int first_kex;
3348 * Set up the preferred ciphers. (NULL => warn below here)
3350 n_preferred_ciphers = 0;
3351 for (i = 0; i < CIPHER_MAX; i++) {
3352 switch (cfg.ssh_cipherlist[i]) {
3353 case CIPHER_BLOWFISH:
3354 preferred_ciphers[n_preferred_ciphers] = &ssh2_blowfish;
3355 n_preferred_ciphers++;
3358 if (cfg.ssh2_des_cbc) {
3359 preferred_ciphers[n_preferred_ciphers] = &ssh2_des;
3360 n_preferred_ciphers++;
3364 preferred_ciphers[n_preferred_ciphers] = &ssh2_3des;
3365 n_preferred_ciphers++;
3368 preferred_ciphers[n_preferred_ciphers] = &ssh2_aes;
3369 n_preferred_ciphers++;
3372 /* Flag for later. Don't bother if it's the last in
3374 if (i < CIPHER_MAX - 1) {
3375 preferred_ciphers[n_preferred_ciphers] = NULL;
3376 n_preferred_ciphers++;
3383 * Set up preferred compression.
3385 if (cfg.compression)
3386 preferred_comp = &ssh_zlib;
3388 preferred_comp = &ssh_comp_none;
3391 * Be prepared to work around the buggy MAC problem.
3393 if (cfg.buggymac || (ssh_remote_bugs & BUG_SSH2_HMAC))
3394 maclist = buggymacs, nmacs = lenof(buggymacs);
3396 maclist = macs, nmacs = lenof(macs);
3400 * Construct and send our key exchange packet.
3402 ssh2_pkt_init(SSH2_MSG_KEXINIT);
3403 for (i = 0; i < 16; i++)
3404 ssh2_pkt_addbyte((unsigned char) random_byte());
3405 /* List key exchange algorithms. */
3406 ssh2_pkt_addstring_start();
3407 for (i = 0; i < lenof(kex_algs); i++) {
3408 ssh2_pkt_addstring_str(kex_algs[i]->name);
3409 if (i < lenof(kex_algs) - 1)
3410 ssh2_pkt_addstring_str(",");
3412 /* List server host key algorithms. */
3413 ssh2_pkt_addstring_start();
3414 for (i = 0; i < lenof(hostkey_algs); i++) {
3415 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
3416 if (i < lenof(hostkey_algs) - 1)
3417 ssh2_pkt_addstring_str(",");
3419 /* List client->server encryption algorithms. */
3420 ssh2_pkt_addstring_start();
3421 cipherstr_started = 0;
3422 for (i = 0; i < n_preferred_ciphers; i++) {
3423 const struct ssh2_ciphers *c = preferred_ciphers[i];
3424 if (!c) continue; /* warning flag */
3425 for (j = 0; j < c->nciphers; j++) {
3426 if (cipherstr_started)
3427 ssh2_pkt_addstring_str(",");
3428 ssh2_pkt_addstring_str(c->list[j]->name);
3429 cipherstr_started = 1;
3432 /* List server->client encryption algorithms. */
3433 ssh2_pkt_addstring_start();
3434 cipherstr_started = 0;
3435 for (i = 0; i < n_preferred_ciphers; i++) {
3436 const struct ssh2_ciphers *c = preferred_ciphers[i];
3437 if (!c) continue; /* warning flag */
3438 for (j = 0; j < c->nciphers; j++) {
3439 if (cipherstr_started)
3440 ssh2_pkt_addstring_str(",");
3441 ssh2_pkt_addstring_str(c->list[j]->name);
3442 cipherstr_started = 1;
3445 /* List client->server MAC algorithms. */
3446 ssh2_pkt_addstring_start();
3447 for (i = 0; i < nmacs; i++) {
3448 ssh2_pkt_addstring_str(maclist[i]->name);
3450 ssh2_pkt_addstring_str(",");
3452 /* List server->client MAC algorithms. */
3453 ssh2_pkt_addstring_start();
3454 for (i = 0; i < nmacs; i++) {
3455 ssh2_pkt_addstring_str(maclist[i]->name);
3457 ssh2_pkt_addstring_str(",");
3459 /* List client->server compression algorithms. */
3460 ssh2_pkt_addstring_start();
3461 for (i = 0; i < lenof(compressions) + 1; i++) {
3462 const struct ssh_compress *c =
3463 i == 0 ? preferred_comp : compressions[i - 1];
3464 ssh2_pkt_addstring_str(c->name);
3465 if (i < lenof(compressions))
3466 ssh2_pkt_addstring_str(",");
3468 /* List server->client compression algorithms. */
3469 ssh2_pkt_addstring_start();
3470 for (i = 0; i < lenof(compressions) + 1; i++) {
3471 const struct ssh_compress *c =
3472 i == 0 ? preferred_comp : compressions[i - 1];
3473 ssh2_pkt_addstring_str(c->name);
3474 if (i < lenof(compressions))
3475 ssh2_pkt_addstring_str(",");
3477 /* List client->server languages. Empty list. */
3478 ssh2_pkt_addstring_start();
3479 /* List server->client languages. Empty list. */
3480 ssh2_pkt_addstring_start();
3481 /* First KEX packet does _not_ follow, because we're not that brave. */
3482 ssh2_pkt_addbool(FALSE);
3484 ssh2_pkt_adduint32(0);
3486 exhash = exhashbase;
3487 sha_string(&exhash, pktout.data + 5, pktout.length - 5);
3493 sha_string(&exhash, pktin.data + 5, pktin.length - 5);
3496 * Now examine the other side's KEXINIT to see what we're up
3499 if (pktin.type != SSH2_MSG_KEXINIT) {
3500 bombout(("expected key exchange packet from server"));
3505 cscipher_tobe = NULL;
3506 sccipher_tobe = NULL;
3511 pktin.savedpos += 16; /* skip garbage cookie */
3512 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
3513 for (i = 0; i < lenof(kex_algs); i++) {
3514 if (in_commasep_string(kex_algs[i]->name, str, len)) {
3519 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
3520 for (i = 0; i < lenof(hostkey_algs); i++) {
3521 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
3522 hostkey = hostkey_algs[i];
3526 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
3528 for (i = 0; i < n_preferred_ciphers; i++) {
3529 const struct ssh2_ciphers *c = preferred_ciphers[i];
3533 for (j = 0; j < c->nciphers; j++) {
3534 if (in_commasep_string(c->list[j]->name, str, len)) {
3535 cscipher_tobe = c->list[j];
3540 if (cscipher_tobe) {
3542 askcipher(cscipher_tobe->name, 1);
3546 if (!cscipher_tobe) {
3547 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str));
3551 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
3553 for (i = 0; i < n_preferred_ciphers; i++) {
3554 const struct ssh2_ciphers *c = preferred_ciphers[i];
3558 for (j = 0; j < c->nciphers; j++) {
3559 if (in_commasep_string(c->list[j]->name, str, len)) {
3560 sccipher_tobe = c->list[j];
3565 if (sccipher_tobe) {
3567 askcipher(sccipher_tobe->name, 2);
3571 if (!sccipher_tobe) {
3572 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str));
3576 ssh2_pkt_getstring(&str, &len); /* client->server mac */
3577 for (i = 0; i < nmacs; i++) {
3578 if (in_commasep_string(maclist[i]->name, str, len)) {
3579 csmac_tobe = maclist[i];
3583 ssh2_pkt_getstring(&str, &len); /* server->client mac */
3584 for (i = 0; i < nmacs; i++) {
3585 if (in_commasep_string(maclist[i]->name, str, len)) {
3586 scmac_tobe = maclist[i];
3590 ssh2_pkt_getstring(&str, &len); /* client->server compression */
3591 for (i = 0; i < lenof(compressions) + 1; i++) {
3592 const struct ssh_compress *c =
3593 i == 0 ? preferred_comp : compressions[i - 1];
3594 if (in_commasep_string(c->name, str, len)) {
3599 ssh2_pkt_getstring(&str, &len); /* server->client compression */
3600 for (i = 0; i < lenof(compressions) + 1; i++) {
3601 const struct ssh_compress *c =
3602 i == 0 ? preferred_comp : compressions[i - 1];
3603 if (in_commasep_string(c->name, str, len)) {
3610 * Work out the number of bits of key we will need from the key
3611 * exchange. We start with the maximum key length of either
3617 csbits = cscipher_tobe->keylen;
3618 scbits = sccipher_tobe->keylen;
3619 nbits = (csbits > scbits ? csbits : scbits);
3621 /* The keys only have 160-bit entropy, since they're based on
3622 * a SHA-1 hash. So cap the key size at 160 bits. */
3627 * If we're doing Diffie-Hellman group exchange, start by
3628 * requesting a group.
3630 if (kex == &ssh_diffiehellman_gex) {
3631 logevent("Doing Diffie-Hellman group exchange");
3632 ssh_pkt_ctx |= SSH2_PKTCTX_DHGEX;
3634 * Work out how big a DH group we will need to allow that
3637 pbits = 512 << ((nbits - 1) / 64);
3638 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
3639 ssh2_pkt_adduint32(pbits);
3643 if (pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
3644 bombout(("expected key exchange group packet from server"));
3647 p = ssh2_pkt_getmp();
3648 g = ssh2_pkt_getmp();
3649 dh_setup_group(p, g);
3650 kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
3651 kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
3653 ssh_pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
3655 kex_init_value = SSH2_MSG_KEXDH_INIT;
3656 kex_reply_value = SSH2_MSG_KEXDH_REPLY;
3659 logevent("Doing Diffie-Hellman key exchange");
3661 * Now generate and send e for Diffie-Hellman.
3663 e = dh_create_e(nbits * 2);
3664 ssh2_pkt_init(kex_init_value);
3669 if (pktin.type != kex_reply_value) {
3670 bombout(("expected key exchange reply packet from server"));
3673 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
3674 f = ssh2_pkt_getmp();
3675 ssh2_pkt_getstring(&sigdata, &siglen);
3679 sha_string(&exhash, hostkeydata, hostkeylen);
3680 if (kex == &ssh_diffiehellman_gex) {
3681 sha_uint32(&exhash, pbits);
3682 sha_mpint(&exhash, p);
3683 sha_mpint(&exhash, g);
3685 sha_mpint(&exhash, e);
3686 sha_mpint(&exhash, f);
3687 sha_mpint(&exhash, K);
3688 SHA_Final(&exhash, exchange_hash);
3693 debug(("Exchange hash is:\n"));
3694 dmemdump(exchange_hash, 20);
3697 hkey = hostkey->newkey(hostkeydata, hostkeylen);
3699 !hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) {
3700 bombout(("Server's host key did not match the signature supplied"));
3705 * Authenticate remote host: verify host key. (We've already
3706 * checked the signature of the exchange hash.)
3708 keystr = hostkey->fmtkey(hkey);
3709 fingerprint = hostkey->fingerprint(hkey);
3710 verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
3711 keystr, fingerprint);
3712 if (first_kex) { /* don't bother logging this in rekeys */
3713 logevent("Host key fingerprint is:");
3714 logevent(fingerprint);
3718 hostkey->freekey(hkey);
3721 * Send SSH2_MSG_NEWKEYS.
3723 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
3727 * Expect SSH2_MSG_NEWKEYS from server.
3730 if (pktin.type != SSH2_MSG_NEWKEYS) {
3731 bombout(("expected new-keys packet from server"));
3736 * Create and initialise session keys.
3738 cscipher = cscipher_tobe;
3739 sccipher = sccipher_tobe;
3742 cscomp = cscomp_tobe;
3743 sccomp = sccomp_tobe;
3744 cscomp->compress_init();
3745 sccomp->decompress_init();
3747 * Set IVs after keys. Here we use the exchange hash from the
3748 * _first_ key exchange.
3751 memcpy(ssh2_session_id, exchange_hash, sizeof(exchange_hash));
3752 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'C', keyspace);
3753 cscipher->setcskey(keyspace);
3754 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'D', keyspace);
3755 sccipher->setsckey(keyspace);
3756 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'A', keyspace);
3757 cscipher->setcsiv(keyspace);
3758 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'B', keyspace);
3759 sccipher->setsciv(keyspace);
3760 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'E', keyspace);
3761 csmac->setcskey(keyspace);
3762 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'F', keyspace);
3763 scmac->setsckey(keyspace);
3766 * If this is the first key exchange phase, we must pass the
3767 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
3768 * wants to see it but because it will need time to initialise
3769 * itself before it sees an actual packet. In subsequent key
3770 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
3771 * it would only confuse the layer above.
3779 * Now we're encrypting. Begin returning 1 to the protocol main
3780 * function so that other things can run on top of the
3781 * transport. If we ever see a KEXINIT, we must go back to the
3784 while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT)) {
3787 logevent("Server initiated key re-exchange");
3788 goto begin_key_exchange;
3794 * Add data to an SSH2 channel output buffer.
3796 static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
3799 bufchain_add(&c->v.v2.outbuffer, buf, len);
3803 * Attempt to send data on an SSH2 channel.
3805 static int ssh2_try_send(struct ssh_channel *c)
3807 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
3810 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
3811 if ((unsigned)len > c->v.v2.remwindow)
3812 len = c->v.v2.remwindow;
3813 if ((unsigned)len > c->v.v2.remmaxpkt)
3814 len = c->v.v2.remmaxpkt;
3815 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
3816 ssh2_pkt_adduint32(c->remoteid);
3817 ssh2_pkt_addstring_start();
3818 ssh2_pkt_addstring_data(data, len);
3820 bufchain_consume(&c->v.v2.outbuffer, len);
3821 c->v.v2.remwindow -= len;
3825 * After having sent as much data as we can, return the amount
3828 return bufchain_size(&c->v.v2.outbuffer);
3832 * Potentially enlarge the window on an SSH2 channel.
3834 static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
3837 * Never send WINDOW_ADJUST for a channel that the remote side
3838 * already thinks it's closed; there's no point, since it won't
3839 * be sending any more data anyway.
3844 if (newwin > c->v.v2.locwindow) {
3845 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
3846 ssh2_pkt_adduint32(c->remoteid);
3847 ssh2_pkt_adduint32(newwin - c->v.v2.locwindow);
3849 c->v.v2.locwindow = newwin;
3854 * Handle the SSH2 userauth and connection layers.
3856 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
3859 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
3861 AUTH_KEYBOARD_INTERACTIVE
3865 AUTH_TYPE_PUBLICKEY,
3866 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
3867 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
3869 AUTH_TYPE_KEYBOARD_INTERACTIVE,
3870 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
3872 static int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
3873 static int tried_pubkey_config, tried_agent, tried_keyb_inter;
3874 static int kbd_inter_running;
3875 static int we_are_in;
3876 static int num_prompts, echo;
3877 static char username[100];
3878 static char pwprompt[200];
3879 static char password[100];
3880 static void *publickey_blob;
3881 static int publickey_bloblen;
3886 * Request userauth protocol, and await a response to it.
3888 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
3889 ssh2_pkt_addstring("ssh-userauth");
3891 crWaitUntilV(ispkt);
3892 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
3893 bombout(("Server refused user authentication protocol"));
3898 * We repeat this whole loop, including the username prompt,
3899 * until we manage a successful authentication. If the user
3900 * types the wrong _password_, they are sent back to the
3901 * beginning to try another username. (If they specify a
3902 * username in the config, they are never asked, even if they
3903 * do give a wrong password.)
3905 * I think this best serves the needs of
3907 * - the people who have no configuration, no keys, and just
3908 * want to try repeated (username,password) pairs until they
3909 * type both correctly
3911 * - people who have keys and configuration but occasionally
3912 * need to fall back to passwords
3914 * - people with a key held in Pageant, who might not have
3915 * logged in to a particular machine before; so they want to
3916 * type a username, and then _either_ their key will be
3917 * accepted, _or_ they will type a password. If they mistype
3918 * the username they will want to be able to get back and
3930 if (*username && !cfg.change_username) {
3932 * We got a username last time round this loop, and
3933 * with change_username turned off we don't try to get
3936 } else if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
3938 if (!ssh_get_line("login as: ",
3939 username, sizeof(username), FALSE)) {
3941 * get_line failed to get a username.
3944 logevent("No username provided. Abandoning session.");
3945 ssh_state = SSH_STATE_CLOSED;
3949 c_write_str("login as: ");
3952 crWaitUntilV(!ispkt);
3954 switch (c = *in++) {
3963 c_write_str("\b \b");
3970 c_write_str("\b \b");
3980 if (((c >= ' ' && c <= '~') ||
3981 ((unsigned char) c >= 160))
3982 && pos < sizeof(username)-1) {
3983 username[pos++] = c;
3990 c_write_str("\r\n");
3991 username[strcspn(username, "\n\r")] = '\0';
3994 strncpy(username, cfg.username, 99);
3995 username[99] = '\0';
3996 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
3997 sprintf(stuff, "Using username \"%s\".\r\n", username);
4003 * Send an authentication request using method "none": (a)
4004 * just in case it succeeds, and (b) so that we know what
4005 * authentication methods we can usefully try next.
4007 ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4009 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4010 ssh2_pkt_addstring(username);
4011 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4012 ssh2_pkt_addstring("none"); /* method */
4014 type = AUTH_TYPE_NONE;
4018 tried_pubkey_config = FALSE;
4019 tried_agent = FALSE;
4020 tried_keyb_inter = FALSE;
4021 kbd_inter_running = FALSE;
4022 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4024 publickey_blob = ssh2_userkey_loadpub(cfg.keyfile, NULL,
4025 &publickey_bloblen);
4027 publickey_blob = NULL;
4031 * Wait for the result of the last authentication request.
4034 crWaitUntilV(ispkt);
4035 while (pktin.type == SSH2_MSG_USERAUTH_BANNER) {
4039 * Don't show the banner if we're operating in
4040 * non-verbose non-interactive mode. (It's probably
4041 * a script, which means nobody will read the
4042 * banner _anyway_, and moreover the printing of
4043 * the banner will screw up processing on the
4044 * output of (say) plink.)
4046 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
4047 ssh2_pkt_getstring(&banner, &size);
4049 c_write_untrusted(banner, size);
4051 crWaitUntilV(ispkt);
4053 if (pktin.type == SSH2_MSG_USERAUTH_SUCCESS) {
4054 logevent("Access granted");
4059 if (kbd_inter_running &&
4060 pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
4062 * This is a further prompt in keyboard-interactive
4063 * authentication. Do nothing.
4065 } else if (pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
4066 bombout(("Strange packet received during authentication: type %d",
4074 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4075 * we can look at the string in it and know what we can
4076 * helpfully try next.
4078 if (pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
4081 ssh2_pkt_getstring(&methods, &methlen);
4082 kbd_inter_running = FALSE;
4083 if (!ssh2_pkt_getbool()) {
4085 * We have received an unequivocal Access
4086 * Denied. This can translate to a variety of
4089 * - if we'd just tried "none" authentication,
4090 * it's not worth printing anything at all
4092 * - if we'd just tried a public key _offer_,
4093 * the message should be "Server refused our
4094 * key" (or no message at all if the key
4095 * came from Pageant)
4097 * - if we'd just tried anything else, the
4098 * message really should be "Access denied".
4100 * Additionally, if we'd just tried password
4101 * authentication, we should break out of this
4102 * whole loop so as to go back to the username
4105 if (type == AUTH_TYPE_NONE) {
4107 } else if (type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
4108 type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
4109 if (type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
4110 c_write_str("Server refused our key\r\n");
4111 logevent("Server refused public key");
4112 } else if (type == AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4113 /* server declined keyboard-interactive; ignore */
4115 c_write_str("Access denied\r\n");
4116 logevent("Access denied");
4117 if (type == AUTH_TYPE_PASSWORD) {
4123 c_write_str("Further authentication required\r\n");
4124 logevent("Further authentication required");
4128 in_commasep_string("publickey", methods, methlen);
4130 in_commasep_string("password", methods, methlen);
4131 can_keyb_inter = cfg.try_ki_auth &&
4132 in_commasep_string("keyboard-interactive", methods, methlen);
4136 ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4138 if (!method && can_pubkey && agent_exists() && !tried_agent) {
4140 * Attempt public-key authentication using Pageant.
4142 static unsigned char request[5], *response, *p;
4143 static int responselen;
4144 static int i, nkeys;
4145 static int authed = FALSE;
4148 ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
4152 logevent("Pageant is running. Requesting keys.");
4154 /* Request the keys held by the agent. */
4155 PUT_32BIT(request, 1);
4156 request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
4157 agent_query(request, 5, &r, &responselen);
4158 response = (unsigned char *) r;
4159 if (response && responselen >= 5 &&
4160 response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
4162 nkeys = GET_32BIT(p);
4166 sprintf(buf, "Pageant has %d SSH2 keys", nkeys);
4169 for (i = 0; i < nkeys; i++) {
4170 static char *pkblob, *alg, *commentp;
4171 static int pklen, alglen, commentlen;
4172 static int siglen, retlen, len;
4173 static char *q, *agentreq, *ret;
4178 sprintf(buf, "Trying Pageant key #%d", i);
4181 pklen = GET_32BIT(p);
4183 if (publickey_blob &&
4184 pklen == publickey_bloblen &&
4185 !memcmp(p, publickey_blob, publickey_bloblen)) {
4186 logevent("This key matches configured key file");
4187 tried_pubkey_config = 1;
4191 alglen = GET_32BIT(pkblob);
4193 commentlen = GET_32BIT(p);
4197 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4198 ssh2_pkt_addstring(username);
4199 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4200 ssh2_pkt_addstring("publickey"); /* method */
4201 ssh2_pkt_addbool(FALSE); /* no signature included */
4202 ssh2_pkt_addstring_start();
4203 ssh2_pkt_addstring_data(alg, alglen);
4204 ssh2_pkt_addstring_start();
4205 ssh2_pkt_addstring_data(pkblob, pklen);
4208 crWaitUntilV(ispkt);
4209 if (pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
4210 logevent("Key refused");
4214 if (flags & FLAG_VERBOSE) {
4216 ("Authenticating with public key \"");
4217 c_write(commentp, commentlen);
4218 c_write_str("\" from agent\r\n");
4222 * Server is willing to accept the key.
4223 * Construct a SIGN_REQUEST.
4225 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4226 ssh2_pkt_addstring(username);
4227 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4228 ssh2_pkt_addstring("publickey"); /* method */
4229 ssh2_pkt_addbool(TRUE);
4230 ssh2_pkt_addstring_start();
4231 ssh2_pkt_addstring_data(alg, alglen);
4232 ssh2_pkt_addstring_start();
4233 ssh2_pkt_addstring_data(pkblob, pklen);
4235 siglen = pktout.length - 5 + 4 + 20;
4236 len = 1; /* message type */
4237 len += 4 + pklen; /* key blob */
4238 len += 4 + siglen; /* data to sign */
4239 len += 4; /* flags */
4240 agentreq = smalloc(4 + len);
4241 PUT_32BIT(agentreq, len);
4243 *q++ = SSH2_AGENTC_SIGN_REQUEST;
4244 PUT_32BIT(q, pklen);
4246 memcpy(q, pkblob, pklen);
4248 PUT_32BIT(q, siglen);
4250 /* Now the data to be signed... */
4253 memcpy(q, ssh2_session_id, 20);
4255 memcpy(q, pktout.data + 5, pktout.length - 5);
4256 q += pktout.length - 5;
4257 /* And finally the (zero) flags word. */
4259 agent_query(agentreq, len + 4, &vret, &retlen);
4263 if (ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
4264 logevent("Sending Pageant's response");
4265 ssh2_pkt_addstring_start();
4266 ssh2_pkt_addstring_data(ret + 9,
4274 ("Pageant failed to answer challenge");
4284 if (!method && can_pubkey && *cfg.keyfile
4285 && !tried_pubkey_config) {
4286 unsigned char *pub_blob;
4287 char *algorithm, *comment;
4290 tried_pubkey_config = TRUE;
4292 ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
4295 * Try the public key supplied in the configuration.
4297 * First, offer the public blob to see if the server is
4298 * willing to accept it.
4300 pub_blob = ssh2_userkey_loadpub(cfg.keyfile, &algorithm,
4303 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4304 ssh2_pkt_addstring(username);
4305 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4306 ssh2_pkt_addstring("publickey"); /* method */
4307 ssh2_pkt_addbool(FALSE); /* no signature included */
4308 ssh2_pkt_addstring(algorithm);
4309 ssh2_pkt_addstring_start();
4310 ssh2_pkt_addstring_data(pub_blob, pub_blob_len);
4312 logevent("Offered public key"); /* FIXME */
4314 crWaitUntilV(ispkt);
4315 if (pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
4317 type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
4318 continue; /* key refused; give up on it */
4321 logevent("Offer of public key accepted");
4323 * Actually attempt a serious authentication using
4326 if (ssh2_userkey_encrypted(cfg.keyfile, &comment)) {
4328 "Passphrase for key \"%.100s\": ",
4334 c_write_str("Authenticating with public key \"");
4335 c_write_str(comment);
4336 c_write_str("\"\r\n");
4337 method = AUTH_PUBLICKEY_FILE;
4341 if (!method && can_keyb_inter && !tried_keyb_inter) {
4342 method = AUTH_KEYBOARD_INTERACTIVE;
4343 type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4344 tried_keyb_inter = TRUE;
4346 ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER;
4348 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4349 ssh2_pkt_addstring(username);
4350 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4351 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4352 ssh2_pkt_addstring(""); /* lang */
4353 ssh2_pkt_addstring("");
4356 crWaitUntilV(ispkt);
4357 if (pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
4358 if (pktin.type == SSH2_MSG_USERAUTH_FAILURE)
4360 logevent("Keyboard-interactive authentication refused");
4361 type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
4365 kbd_inter_running = TRUE;
4368 if (kbd_inter_running) {
4369 method = AUTH_KEYBOARD_INTERACTIVE;
4370 type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4371 tried_keyb_inter = TRUE;
4373 ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER;
4375 /* We've got packet with that "interactive" info
4376 dump banners, and set its prompt as ours */
4378 char *name, *inst, *lang, *prompt;
4379 int name_len, inst_len, lang_len, prompt_len;
4380 ssh2_pkt_getstring(&name, &name_len);
4381 ssh2_pkt_getstring(&inst, &inst_len);
4382 ssh2_pkt_getstring(&lang, &lang_len);
4384 c_write_untrusted(name, name_len);
4386 c_write_untrusted(inst, inst_len);
4387 num_prompts = ssh2_pkt_getuint32();
4389 ssh2_pkt_getstring(&prompt, &prompt_len);
4390 strncpy(pwprompt, prompt, sizeof(pwprompt));
4391 pwprompt[prompt_len < sizeof(pwprompt) ?
4392 prompt_len : sizeof(pwprompt)-1] = '\0';
4395 echo = ssh2_pkt_getbool();
4399 if (!method && can_passwd) {
4400 method = AUTH_PASSWORD;
4401 ssh_pkt_ctx |= SSH2_PKTCTX_PASSWORD;
4402 sprintf(pwprompt, "%.90s@%.90s's password: ", username,
4409 if (!ssh_get_line(pwprompt, password,
4410 sizeof(password), TRUE)) {
4412 * get_line failed to get a password (for
4413 * example because one was supplied on the
4414 * command line which has already failed to
4417 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
4418 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
4420 ("No more passwords available to try");
4421 ssh2_pkt_addstring("en"); /* language tag */
4423 connection_fatal("Unable to authenticate");
4424 ssh_state = SSH_STATE_CLOSED;
4431 c_write_untrusted(pwprompt, strlen(pwprompt));
4436 crWaitUntilV(!ispkt);
4438 switch (c = *in++) {
4459 if (pos < sizeof(password)-1)
4460 password[pos++] = c;
4464 c_write_str("\r\n");
4468 if (method == AUTH_PUBLICKEY_FILE) {
4470 * We have our passphrase. Now try the actual authentication.
4472 struct ssh2_userkey *key;
4474 key = ssh2_load_userkey(cfg.keyfile, password);
4475 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
4476 if (key == SSH2_WRONG_PASSPHRASE) {
4477 c_write_str("Wrong passphrase\r\n");
4478 tried_pubkey_config = FALSE;
4480 c_write_str("Unable to load private key\r\n");
4481 tried_pubkey_config = TRUE;
4483 /* Send a spurious AUTH_NONE to return to the top. */
4484 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4485 ssh2_pkt_addstring(username);
4486 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4487 ssh2_pkt_addstring("none"); /* method */
4489 type = AUTH_TYPE_NONE;
4491 unsigned char *blob, *sigdata;
4492 int blob_len, sigdata_len;
4495 * We have loaded the private key and the server
4496 * has announced that it's willing to accept it.
4497 * Hallelujah. Generate a signature and send it.
4499 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4500 ssh2_pkt_addstring(username);
4501 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4502 ssh2_pkt_addstring("publickey"); /* method */
4503 ssh2_pkt_addbool(TRUE);
4504 ssh2_pkt_addstring(key->alg->name);
4505 blob = key->alg->public_blob(key->data, &blob_len);
4506 ssh2_pkt_addstring_start();
4507 ssh2_pkt_addstring_data(blob, blob_len);
4511 * The data to be signed is:
4515 * followed by everything so far placed in the
4518 sigdata_len = pktout.length - 5 + 4 + 20;
4519 sigdata = smalloc(sigdata_len);
4520 PUT_32BIT(sigdata, 20);
4521 memcpy(sigdata + 4, ssh2_session_id, 20);
4522 memcpy(sigdata + 24, pktout.data + 5,
4525 key->alg->sign(key->data, sigdata, sigdata_len,
4527 ssh2_pkt_addstring_start();
4528 ssh2_pkt_addstring_data(blob, blob_len);
4533 type = AUTH_TYPE_PUBLICKEY;
4535 } else if (method == AUTH_PASSWORD) {
4537 * We send the password packet lumped tightly together with
4538 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4539 * string long enough to make the total length of the two
4540 * packets constant. This should ensure that a passive
4541 * listener doing traffic analyis can't work out the length
4544 * For this to work, we need an assumption about the
4545 * maximum length of the password packet. I think 256 is
4546 * pretty conservative. Anyone using a password longer than
4547 * that probably doesn't have much to worry about from
4548 * people who find out how long their password is!
4550 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4551 ssh2_pkt_addstring(username);
4552 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4553 ssh2_pkt_addstring("password");
4554 ssh2_pkt_addbool(FALSE);
4555 ssh2_pkt_addstring(password);
4558 * We'll include a string that's an exact multiple of the
4559 * cipher block size. If the cipher is NULL for some
4560 * reason, we don't do this trick at all because we gain
4566 stringlen = (256 - deferred_len);
4567 stringlen += cscipher->blksize - 1;
4568 stringlen -= (stringlen % cscipher->blksize);
4571 * Temporarily disable actual compression,
4572 * so we can guarantee to get this string
4573 * exactly the length we want it. The
4574 * compression-disabling routine should
4575 * return an integer indicating how many
4576 * bytes we should adjust our string length
4579 stringlen -= cscomp->disable_compression();
4581 ssh2_pkt_init(SSH2_MSG_IGNORE);
4582 ssh2_pkt_addstring_start();
4583 for (i = 0; i < stringlen; i++) {
4584 char c = (char) random_byte();
4585 ssh2_pkt_addstring_data(&c, 1);
4589 ssh_pkt_defersend();
4590 logevent("Sent password");
4591 type = AUTH_TYPE_PASSWORD;
4592 } else if (method == AUTH_KEYBOARD_INTERACTIVE) {
4593 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
4594 ssh2_pkt_adduint32(num_prompts);
4595 ssh2_pkt_addstring(password);
4596 memset(password, 0, sizeof(password));
4598 type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4601 ("No supported authentication methods left to try!\r\n");
4603 ("No supported authentications offered. Disconnecting");
4604 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
4605 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
4607 ("No supported authentication methods available");
4608 ssh2_pkt_addstring("en"); /* language tag */
4610 ssh_state = SSH_STATE_CLOSED;
4614 } while (!we_are_in);
4617 * Now we're authenticated for the connection protocol. The
4618 * connection protocol will automatically have started at this
4619 * point; there's no need to send SERVICE_REQUEST.
4623 * So now create a channel with a session in it.
4625 ssh_channels = newtree234(ssh_channelcmp);
4626 mainchan = smalloc(sizeof(struct ssh_channel));
4627 mainchan->localid = alloc_channel_id();
4628 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
4629 ssh2_pkt_addstring("session");
4630 ssh2_pkt_adduint32(mainchan->localid);
4631 mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
4632 ssh2_pkt_adduint32(mainchan->v.v2.locwindow); /* our window size */
4633 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
4635 crWaitUntilV(ispkt);
4636 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
4637 bombout(("Server refused to open a session"));
4639 /* FIXME: error data comes back in FAILURE packet */
4641 if (ssh2_pkt_getuint32() != mainchan->localid) {
4642 bombout(("Server's channel confirmation cited wrong channel"));
4645 mainchan->remoteid = ssh2_pkt_getuint32();
4646 mainchan->type = CHAN_MAINSESSION;
4647 mainchan->closes = 0;
4648 mainchan->v.v2.remwindow = ssh2_pkt_getuint32();
4649 mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32();
4650 bufchain_init(&mainchan->v.v2.outbuffer);
4651 add234(ssh_channels, mainchan);
4652 logevent("Opened channel for session");
4655 * Potentially enable X11 forwarding.
4657 if (cfg.x11_forward) {
4658 char proto[20], data[64];
4659 logevent("Requesting X11 forwarding");
4660 x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
4661 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
4662 ssh2_pkt_adduint32(mainchan->remoteid);
4663 ssh2_pkt_addstring("x11-req");
4664 ssh2_pkt_addbool(1); /* want reply */
4665 ssh2_pkt_addbool(0); /* many connections */
4666 ssh2_pkt_addstring(proto);
4667 ssh2_pkt_addstring(data);
4668 ssh2_pkt_adduint32(0); /* screen number */
4672 crWaitUntilV(ispkt);
4673 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4674 unsigned i = ssh2_pkt_getuint32();
4675 struct ssh_channel *c;
4676 c = find234(ssh_channels, &i, ssh_channelfind);
4678 continue; /* nonexistent channel */
4679 c->v.v2.remwindow += ssh2_pkt_getuint32();
4681 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4683 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
4684 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
4685 bombout(("Unexpected response to X11 forwarding request:"
4686 " packet type %d", pktin.type));
4689 logevent("X11 forwarding refused");
4691 logevent("X11 forwarding enabled");
4692 ssh_X11_fwd_enabled = TRUE;
4697 * Enable port forwardings.
4700 static char *e; /* preserve across crReturn */
4704 char sports[256], dports[256], host[256];
4707 ssh_rportfwds = newtree234(ssh_rportcmp_ssh2);
4708 /* Add port forwardings. */
4713 while (*e && *e != '\t')
4719 while (*e && *e != ':')
4729 dport = atoi(dports);
4730 sport = atoi(sports);
4731 if (sport && dport) {
4733 pfd_addforward(host, dport, sport);
4734 sprintf(buf, "Local port %d forwarding to %s:%d",
4735 sport, host, dport);
4738 struct ssh_rportfwd *pf;
4739 pf = smalloc(sizeof(*pf));
4740 strcpy(pf->dhost, host);
4743 if (add234(ssh_rportfwds, pf) != pf) {
4745 "Duplicate remote port forwarding to %s:%d",
4750 sprintf(buf, "Requesting remote port %d (forwarded to %s:%d)",
4751 sport, host, dport);
4753 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
4754 ssh2_pkt_addstring("tcpip-forward");
4755 ssh2_pkt_addbool(1);/* want reply */
4756 if (cfg.rport_acceptall)
4757 ssh2_pkt_addstring("0.0.0.0");
4759 ssh2_pkt_addstring("127.0.0.1");
4760 ssh2_pkt_adduint32(sport);
4764 crWaitUntilV(ispkt);
4765 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4766 unsigned i = ssh2_pkt_getuint32();
4767 struct ssh_channel *c;
4768 c = find234(ssh_channels, &i, ssh_channelfind);
4770 continue;/* nonexistent channel */
4771 c->v.v2.remwindow += ssh2_pkt_getuint32();
4773 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4775 if (pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
4776 if (pktin.type != SSH2_MSG_REQUEST_FAILURE) {
4777 bombout(("Unexpected response to port "
4778 "forwarding request: packet type %d",
4782 logevent("Server refused this port forwarding");
4784 logevent("Remote port forwarding enabled");
4793 * Potentially enable agent forwarding.
4795 if (cfg.agentfwd && agent_exists()) {
4796 logevent("Requesting OpenSSH-style agent forwarding");
4797 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
4798 ssh2_pkt_adduint32(mainchan->remoteid);
4799 ssh2_pkt_addstring("auth-agent-req@openssh.com");
4800 ssh2_pkt_addbool(1); /* want reply */
4804 crWaitUntilV(ispkt);
4805 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4806 unsigned i = ssh2_pkt_getuint32();
4807 struct ssh_channel *c;
4808 c = find234(ssh_channels, &i, ssh_channelfind);
4810 continue; /* nonexistent channel */
4811 c->v.v2.remwindow += ssh2_pkt_getuint32();
4813 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4815 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
4816 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
4817 bombout(("Unexpected response to agent forwarding request:"
4818 " packet type %d", pktin.type));
4821 logevent("Agent forwarding refused");
4823 logevent("Agent forwarding enabled");
4824 ssh_agentfwd_enabled = TRUE;
4829 * Now allocate a pty for the session.
4832 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
4833 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
4834 ssh2_pkt_addstring("pty-req");
4835 ssh2_pkt_addbool(1); /* want reply */
4836 ssh2_pkt_addstring(cfg.termtype);
4837 ssh2_pkt_adduint32(cols);
4838 ssh2_pkt_adduint32(rows);
4839 ssh2_pkt_adduint32(0); /* pixel width */
4840 ssh2_pkt_adduint32(0); /* pixel height */
4841 ssh2_pkt_addstring_start();
4842 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
4844 ssh_state = SSH_STATE_INTERMED;
4847 crWaitUntilV(ispkt);
4848 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4849 unsigned i = ssh2_pkt_getuint32();
4850 struct ssh_channel *c;
4851 c = find234(ssh_channels, &i, ssh_channelfind);
4853 continue; /* nonexistent channel */
4854 c->v.v2.remwindow += ssh2_pkt_getuint32();
4856 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4858 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
4859 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
4860 bombout(("Unexpected response to pty request:"
4861 " packet type %d", pktin.type));
4864 c_write_str("Server refused to allocate pty\r\n");
4865 ssh_editing = ssh_echoing = 1;
4867 logevent("Allocated pty");
4870 ssh_editing = ssh_echoing = 1;
4874 * Start a shell or a remote command. We may have to attempt
4875 * this twice if the config data has provided a second choice
4882 if (ssh_fallback_cmd) {
4883 subsys = cfg.ssh_subsys2;
4884 cmd = cfg.remote_cmd_ptr2;
4886 subsys = cfg.ssh_subsys;
4887 cmd = cfg.remote_cmd_ptr;
4890 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
4891 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
4893 ssh2_pkt_addstring("subsystem");
4894 ssh2_pkt_addbool(1); /* want reply */
4895 ssh2_pkt_addstring(cmd);
4897 ssh2_pkt_addstring("exec");
4898 ssh2_pkt_addbool(1); /* want reply */
4899 ssh2_pkt_addstring(cmd);
4901 ssh2_pkt_addstring("shell");
4902 ssh2_pkt_addbool(1); /* want reply */
4906 crWaitUntilV(ispkt);
4907 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4908 unsigned i = ssh2_pkt_getuint32();
4909 struct ssh_channel *c;
4910 c = find234(ssh_channels, &i, ssh_channelfind);
4912 continue; /* nonexistent channel */
4913 c->v.v2.remwindow += ssh2_pkt_getuint32();
4915 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4916 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
4917 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
4918 bombout(("Unexpected response to shell/command request:"
4919 " packet type %d", pktin.type));
4923 * We failed to start the command. If this is the
4924 * fallback command, we really are finished; if it's
4925 * not, and if the fallback command exists, try falling
4926 * back to it before complaining.
4928 if (!ssh_fallback_cmd && cfg.remote_cmd_ptr2 != NULL) {
4929 logevent("Primary command failed; attempting fallback");
4930 ssh_fallback_cmd = TRUE;
4933 bombout(("Server refused to start a shell/command"));
4936 logevent("Started a shell/command");
4941 ssh_state = SSH_STATE_SESSION;
4945 ssh_special(TS_EOF);
4950 ldisc_send(NULL, 0, 0); /* cause ldisc to notice changes */
4953 static int try_send;
4957 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
4958 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
4961 unsigned i = ssh2_pkt_getuint32();
4962 struct ssh_channel *c;
4963 c = find234(ssh_channels, &i, ssh_channelfind);
4965 continue; /* nonexistent channel */
4966 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
4967 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
4968 continue; /* extended but not stderr */
4969 ssh2_pkt_getstring(&data, &length);
4972 c->v.v2.locwindow -= length;
4974 case CHAN_MAINSESSION:
4976 from_backend(pktin.type ==
4977 SSH2_MSG_CHANNEL_EXTENDED_DATA,
4981 bufsize = x11_send(c->u.x11.s, data, length);
4984 bufsize = pfd_send(c->u.pfd.s, data, length);
4987 while (length > 0) {
4988 if (c->u.a.lensofar < 4) {
4989 int l = min(4 - c->u.a.lensofar, length);
4990 memcpy(c->u.a.msglen + c->u.a.lensofar,
4994 c->u.a.lensofar += l;
4996 if (c->u.a.lensofar == 4) {
4998 4 + GET_32BIT(c->u.a.msglen);
4999 c->u.a.message = smalloc(c->u.a.totallen);
5000 memcpy(c->u.a.message, c->u.a.msglen, 4);
5002 if (c->u.a.lensofar >= 4 && length > 0) {
5004 min(c->u.a.totallen - c->u.a.lensofar,
5006 memcpy(c->u.a.message + c->u.a.lensofar,
5010 c->u.a.lensofar += l;
5012 if (c->u.a.lensofar == c->u.a.totallen) {
5013 void *reply, *sentreply;
5015 agent_query(c->u.a.message,
5016 c->u.a.totallen, &reply,
5021 /* Fake SSH_AGENT_FAILURE. */
5022 sentreply = "\0\0\0\1\5";
5025 ssh2_add_channel_data(c, sentreply,
5030 sfree(c->u.a.message);
5031 c->u.a.lensofar = 0;
5038 * If we are not buffering too much data,
5039 * enlarge the window again at the remote side.
5041 if (bufsize < OUR_V2_WINSIZE)
5042 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
5044 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
5045 ssh_state = SSH_STATE_CLOSED;
5046 logevent("Received disconnect message");
5048 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
5049 unsigned i = ssh2_pkt_getuint32();
5050 struct ssh_channel *c;
5052 c = find234(ssh_channels, &i, ssh_channelfind);
5054 continue; /* nonexistent channel */
5056 if (c->type == CHAN_X11) {
5058 * Remote EOF on an X11 channel means we should
5059 * wrap up and close the channel ourselves.
5061 x11_close(c->u.x11.s);
5063 } else if (c->type == CHAN_AGENT) {
5065 } else if (c->type == CHAN_SOCKDATA) {
5066 pfd_close(c->u.pfd.s);
5069 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
5070 unsigned i = ssh2_pkt_getuint32();
5071 struct ssh_channel *c;
5073 c = find234(ssh_channels, &i, ssh_channelfind);
5075 continue; /* nonexistent channel */
5076 /* Do pre-close processing on the channel. */
5078 case CHAN_MAINSESSION:
5079 break; /* nothing to see here, move along */
5081 if (c->u.x11.s != NULL)
5082 x11_close(c->u.x11.s);
5089 if (c->u.pfd.s != NULL)
5090 pfd_close(c->u.pfd.s);
5094 if (c->closes == 0) {
5095 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5096 ssh2_pkt_adduint32(c->remoteid);
5099 del234(ssh_channels, c);
5100 bufchain_clear(&c->v.v2.outbuffer);
5104 * See if that was the last channel left open.
5106 if (count234(ssh_channels) == 0) {
5109 * We used to send SSH_MSG_DISCONNECT here,
5110 * because I'd believed that _every_ conforming
5111 * SSH2 connection had to end with a disconnect
5112 * being sent by at least one side; apparently
5113 * I was wrong and it's perfectly OK to
5114 * unceremoniously slam the connection shut
5115 * when you're done, and indeed OpenSSH feels
5116 * this is more polite than sending a
5117 * DISCONNECT. So now we don't.
5119 logevent("All channels closed. Disconnecting");
5120 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5121 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
5122 ssh2_pkt_addstring("All open channels closed");
5123 ssh2_pkt_addstring("en"); /* language tag */
5126 ssh_state = SSH_STATE_CLOSED;
5129 continue; /* remote sends close; ignore (FIXME) */
5130 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5131 unsigned i = ssh2_pkt_getuint32();
5132 struct ssh_channel *c;
5133 c = find234(ssh_channels, &i, ssh_channelfind);
5135 continue; /* nonexistent channel */
5136 c->v.v2.remwindow += ssh2_pkt_getuint32();
5138 } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
5139 unsigned i = ssh2_pkt_getuint32();
5140 struct ssh_channel *c;
5141 c = find234(ssh_channels, &i, ssh_channelfind);
5143 continue; /* nonexistent channel */
5144 if (c->type != CHAN_SOCKDATA_DORMANT)
5145 continue; /* dunno why they're confirming this */
5146 c->remoteid = ssh2_pkt_getuint32();
5147 c->type = CHAN_SOCKDATA;
5148 c->v.v2.remwindow = ssh2_pkt_getuint32();
5149 c->v.v2.remmaxpkt = ssh2_pkt_getuint32();
5150 bufchain_init(&c->v.v2.outbuffer);
5152 pfd_confirm(c->u.pfd.s);
5155 * We have a pending close on this channel,
5156 * which we decided on before the server acked
5157 * the channel open. So now we know the
5158 * remoteid, we can close it again.
5160 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5161 ssh2_pkt_adduint32(c->remoteid);
5164 } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
5165 unsigned i = ssh2_pkt_getuint32();
5166 struct ssh_channel *c;
5167 c = find234(ssh_channels, &i, ssh_channelfind);
5169 continue; /* nonexistent channel */
5170 if (c->type != CHAN_SOCKDATA_DORMANT)
5171 continue; /* dunno why they're failing this */
5173 logevent("Forwarded connection refused by server");
5175 pfd_close(c->u.pfd.s);
5177 del234(ssh_channels, c);
5179 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
5182 int typelen, want_reply;
5183 struct ssh_channel *c;
5185 localid = ssh2_pkt_getuint32();
5186 ssh2_pkt_getstring(&type, &typelen);
5187 want_reply = ssh2_pkt_getbool();
5190 * First, check that the channel exists. Otherwise,
5191 * we can instantly disconnect with a rude message.
5193 c = find234(ssh_channels, &localid, ssh_channelfind);
5196 sprintf(buf, "Received channel request for nonexistent"
5197 " channel %d", localid);
5199 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5200 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
5201 ssh2_pkt_addstring(buf);
5202 ssh2_pkt_addstring("en"); /* language tag */
5204 connection_fatal(buf);
5205 ssh_state = SSH_STATE_CLOSED;
5210 * Having got the channel number, we now look at
5211 * the request type string to see if it's something
5214 if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
5216 /* We recognise "exit-status" on the primary channel. */
5218 ssh_exitcode = ssh2_pkt_getuint32();
5219 sprintf(buf, "Server sent command exit status %d",
5223 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS);
5224 ssh2_pkt_adduint32(c->remoteid);
5229 * This is a channel request we don't know
5230 * about, so we now either ignore the request
5231 * or respond with CHANNEL_FAILURE, depending
5235 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE);
5236 ssh2_pkt_adduint32(c->remoteid);
5240 } else if (pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
5242 int typelen, want_reply;
5244 ssh2_pkt_getstring(&type, &typelen);
5245 want_reply = ssh2_pkt_getbool();
5248 * We currently don't support any global requests
5249 * at all, so we either ignore the request or
5250 * respond with REQUEST_FAILURE, depending on
5254 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
5257 } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) {
5261 struct ssh_channel *c;
5262 unsigned remid, winsize, pktsize;
5263 ssh2_pkt_getstring(&type, &typelen);
5264 c = smalloc(sizeof(struct ssh_channel));
5266 remid = ssh2_pkt_getuint32();
5267 winsize = ssh2_pkt_getuint32();
5268 pktsize = ssh2_pkt_getuint32();
5270 if (typelen == 3 && !memcmp(type, "x11", 3)) {
5271 if (!ssh_X11_fwd_enabled)
5272 error = "X11 forwarding is not enabled";
5273 else if (x11_init(&c->u.x11.s, cfg.x11_display, c) !=
5275 error = "Unable to open an X11 connection";
5279 } else if (typelen == 15 &&
5280 !memcmp(type, "forwarded-tcpip", 15)) {
5281 struct ssh_rportfwd pf, *realpf;
5284 ssh2_pkt_getstring(&dummy, &dummylen);/* skip address */
5285 pf.sport = ssh2_pkt_getuint32();
5286 realpf = find234(ssh_rportfwds, &pf, NULL);
5287 if (realpf == NULL) {
5288 error = "Remote port is not recognised";
5290 char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
5293 sprintf(buf, "Received remote port open request for %s:%d",
5294 realpf->dhost, realpf->dport);
5297 sprintf(buf, "Port open failed: %s", e);
5299 error = "Port open failed";
5301 logevent("Forwarded port opened successfully");
5302 c->type = CHAN_SOCKDATA;
5305 } else if (typelen == 22 &&
5306 !memcmp(type, "auth-agent@openssh.com", 3)) {
5307 if (!ssh_agentfwd_enabled)
5308 error = "Agent forwarding is not enabled";
5310 c->type = CHAN_AGENT; /* identify channel type */
5311 c->u.a.lensofar = 0;
5314 error = "Unsupported channel type requested";
5317 c->remoteid = remid;
5319 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
5320 ssh2_pkt_adduint32(c->remoteid);
5321 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED);
5322 ssh2_pkt_addstring(error);
5323 ssh2_pkt_addstring("en"); /* language tag */
5327 c->localid = alloc_channel_id();
5329 c->v.v2.locwindow = OUR_V2_WINSIZE;
5330 c->v.v2.remwindow = winsize;
5331 c->v.v2.remmaxpkt = pktsize;
5332 bufchain_init(&c->v.v2.outbuffer);
5333 add234(ssh_channels, c);
5334 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5335 ssh2_pkt_adduint32(c->remoteid);
5336 ssh2_pkt_adduint32(c->localid);
5337 ssh2_pkt_adduint32(c->v.v2.locwindow);
5338 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
5342 bombout(("Strange packet received: type %d", pktin.type));
5347 * We have spare data. Add it to the channel buffer.
5349 ssh2_add_channel_data(mainchan, in, inlen);
5354 struct ssh_channel *c;
5356 * Try to send data on all channels if we can.
5358 for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
5359 int bufsize = ssh2_try_send(c);
5362 case CHAN_MAINSESSION:
5363 /* stdin need not receive an unthrottle
5364 * notification since it will be polled */
5367 x11_unthrottle(c->u.x11.s);
5370 /* agent sockets are request/response and need no
5371 * buffer management */
5374 pfd_unthrottle(c->u.pfd.s);
5386 * Handle the top-level SSH2 protocol.
5388 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
5390 if (do_ssh2_transport(in, inlen, ispkt) == 0)
5392 do_ssh2_authconn(in, inlen, ispkt);
5396 * Called to set up the connection.
5398 * Returns an error message, or NULL on success.
5400 static char *ssh_init(char *host, int port, char **realhost, int nodelay)
5405 if (crypto_startup() == 0)
5406 return "Microsoft high encryption pack not installed!";
5412 ssh1_throttle_count = 0;
5413 ssh_overall_bufsize = 0;
5414 ssh_fallback_cmd = 0;
5416 p = connect_to_host(host, port, realhost, nodelay);
5424 * Called to send data down the Telnet connection.
5426 static int ssh_send(char *buf, int len)
5428 if (s == NULL || ssh_protocol == NULL)
5431 ssh_protocol(buf, len, 0);
5433 return ssh_sendbuffer();
5437 * Called to query the current amount of buffered stdin data.
5439 static int ssh_sendbuffer(void)
5443 if (s == NULL || ssh_protocol == NULL)
5447 * If the SSH socket itself has backed up, add the total backup
5448 * size on that to any individual buffer on the stdin channel.
5451 if (ssh_throttled_all)
5452 override_value = ssh_overall_bufsize;
5454 if (ssh_version == 1) {
5455 return override_value;
5456 } else if (ssh_version == 2) {
5457 if (!mainchan || mainchan->closes > 0)
5458 return override_value;
5460 return override_value + bufchain_size(&mainchan->v.v2.outbuffer);
5467 * Called to set the size of the window from SSH's POV.
5469 static void ssh_size(void)
5471 switch (ssh_state) {
5472 case SSH_STATE_BEFORE_SIZE:
5473 case SSH_STATE_PREPACKET:
5474 case SSH_STATE_CLOSED:
5475 break; /* do nothing */
5476 case SSH_STATE_INTERMED:
5477 size_needed = TRUE; /* buffer for later */
5479 case SSH_STATE_SESSION:
5481 if (ssh_version == 1) {
5482 send_packet(SSH1_CMSG_WINDOW_SIZE,
5483 PKT_INT, rows, PKT_INT, cols,
5484 PKT_INT, 0, PKT_INT, 0, PKT_END);
5486 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
5487 ssh2_pkt_adduint32(mainchan->remoteid);
5488 ssh2_pkt_addstring("window-change");
5489 ssh2_pkt_addbool(0);
5490 ssh2_pkt_adduint32(cols);
5491 ssh2_pkt_adduint32(rows);
5492 ssh2_pkt_adduint32(0);
5493 ssh2_pkt_adduint32(0);
5502 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5503 * can send an EOF and collect resulting output (e.g. `plink
5506 static void ssh_special(Telnet_Special code)
5508 if (code == TS_EOF) {
5509 if (ssh_state != SSH_STATE_SESSION) {
5511 * Buffer the EOF in case we are pre-SESSION, so we can
5512 * send it as soon as we reach SESSION.
5518 if (ssh_version == 1) {
5519 send_packet(SSH1_CMSG_EOF, PKT_END);
5521 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
5522 ssh2_pkt_adduint32(mainchan->remoteid);
5525 logevent("Sent EOF message");
5526 } else if (code == TS_PING) {
5527 if (ssh_state == SSH_STATE_CLOSED
5528 || ssh_state == SSH_STATE_PREPACKET) return;
5529 if (ssh_version == 1) {
5530 send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
5532 ssh2_pkt_init(SSH2_MSG_IGNORE);
5533 ssh2_pkt_addstring_start();
5541 void *new_sock_channel(Socket s)
5543 struct ssh_channel *c;
5544 c = smalloc(sizeof(struct ssh_channel));
5547 c->remoteid = -1; /* to be set when open confirmed */
5548 c->localid = alloc_channel_id();
5550 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
5552 add234(ssh_channels, c);
5558 * This is called when stdout/stderr (the entity to which
5559 * from_backend sends data) manages to clear some backlog.
5561 void ssh_unthrottle(int bufsize)
5563 if (ssh_version == 1) {
5564 if (ssh1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
5565 ssh1_stdout_throttling = 0;
5569 if (mainchan && mainchan->closes == 0)
5570 ssh2_set_window(mainchan, OUR_V2_WINSIZE - bufsize);
5574 void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
5576 struct ssh_channel *c = (struct ssh_channel *)channel;
5579 sprintf(buf, "Opening forwarded connection to %.512s:%d", hostname, port);
5582 if (ssh_version == 1) {
5583 send_packet(SSH1_MSG_PORT_OPEN,
5584 PKT_INT, c->localid,
5587 //PKT_STR, <org:orgport>,
5590 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
5591 ssh2_pkt_addstring("direct-tcpip");
5592 ssh2_pkt_adduint32(c->localid);
5593 c->v.v2.locwindow = OUR_V2_WINSIZE;
5594 ssh2_pkt_adduint32(c->v.v2.locwindow);/* our window size */
5595 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
5596 ssh2_pkt_addstring(hostname);
5597 ssh2_pkt_adduint32(port);
5599 * We make up values for the originator data; partly it's
5600 * too much hassle to keep track, and partly I'm not
5601 * convinced the server should be told details like that
5602 * about my local network configuration.
5604 ssh2_pkt_addstring("client-side-connection");
5605 ssh2_pkt_adduint32(0);
5611 static Socket ssh_socket(void)
5616 static int ssh_sendok(void)
5621 static int ssh_ldisc(int option)
5623 if (option == LD_ECHO)
5625 if (option == LD_EDIT)
5630 static int ssh_return_exitcode(void)
5632 return ssh_exitcode;
5635 Backend ssh_backend = {
5642 ssh_return_exitcode,