18 #define logevent(s) { logevent(s); \
19 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
20 { fprintf(stderr, "%s\n", s); fflush(stderr); } }
22 /* logevent, only printf-formatted. */
23 void logeventf(char *fmt
, ...)
29 vsprintf(stuff
, fmt
, ap
);
34 #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \
35 (s ? sk_close(s), s = NULL : 0), \
36 logeventf msg, connection_fatal msg )
38 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
39 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
40 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
41 #define SSH1_CMSG_USER 4 /* 0x4 */
42 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
43 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
44 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
45 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
46 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
47 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
48 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
49 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
50 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
51 #define SSH1_SMSG_FAILURE 15 /* 0xf */
52 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
53 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
54 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
55 #define SSH1_CMSG_EOF 19 /* 0x13 */
56 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
57 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
58 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
59 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
60 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
61 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
62 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
63 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
64 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
65 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
66 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
67 #define SSH1_MSG_IGNORE 32 /* 0x20 */
68 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
69 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
70 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
71 #define SSH1_MSG_DEBUG 36 /* 0x24 */
72 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
73 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
74 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
75 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
76 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
77 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
78 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
80 #define SSH1_AUTH_TIS 5 /* 0x5 */
81 #define SSH1_AUTH_CCARD 16 /* 0x10 */
83 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
84 /* Mask for protoflags we will echo back to server if seen */
85 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
87 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
88 #define SSH2_MSG_IGNORE 2 /* 0x2 */
89 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
90 #define SSH2_MSG_DEBUG 4 /* 0x4 */
91 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
92 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
93 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
94 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
95 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
96 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
97 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
98 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
99 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
100 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
101 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
102 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
103 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
104 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
105 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
106 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
107 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
108 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
109 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
110 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
111 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
112 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
113 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
114 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
115 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
116 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
117 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
118 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
119 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
120 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
121 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
122 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
125 * Packet type contexts, so that ssh2_pkt_type can correctly decode
126 * the ambiguous type numbers back into the correct type strings.
128 #define SSH2_PKTCTX_DHGROUP1 0x0001
129 #define SSH2_PKTCTX_DHGEX 0x0002
130 #define SSH2_PKTCTX_PUBLICKEY 0x0010
131 #define SSH2_PKTCTX_PASSWORD 0x0020
132 #define SSH2_PKTCTX_KBDINTER 0x0040
133 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
135 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
136 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
137 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
138 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
139 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
140 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
141 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
142 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
143 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
144 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
145 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
146 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
147 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
148 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
149 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
151 static const char *const ssh2_disconnect_reasons
[] = {
153 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
154 "SSH_DISCONNECT_PROTOCOL_ERROR",
155 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
156 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
157 "SSH_DISCONNECT_MAC_ERROR",
158 "SSH_DISCONNECT_COMPRESSION_ERROR",
159 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
160 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
161 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
162 "SSH_DISCONNECT_CONNECTION_LOST",
163 "SSH_DISCONNECT_BY_APPLICATION",
164 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
165 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
166 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
167 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
170 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
171 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
172 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
173 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
175 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
178 * Various remote-bug flags.
180 #define BUG_CHOKES_ON_SSH1_IGNORE 1
181 #define BUG_SSH2_HMAC 2
182 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
183 #define BUG_CHOKES_ON_RSA 8
184 #define BUG_SSH2_RSA_PADDING 16
185 #define BUG_SSH2_DERIVEKEY 32
187 static int ssh_pkt_ctx
= 0;
189 #define translate(x) if (type == x) return #x
190 #define translatec(x,ctx) if (type == x && (ssh_pkt_ctx & ctx)) return #x
191 char *ssh1_pkt_type(int type
)
193 translate(SSH1_MSG_DISCONNECT
);
194 translate(SSH1_SMSG_PUBLIC_KEY
);
195 translate(SSH1_CMSG_SESSION_KEY
);
196 translate(SSH1_CMSG_USER
);
197 translate(SSH1_CMSG_AUTH_RSA
);
198 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
199 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
200 translate(SSH1_CMSG_AUTH_PASSWORD
);
201 translate(SSH1_CMSG_REQUEST_PTY
);
202 translate(SSH1_CMSG_WINDOW_SIZE
);
203 translate(SSH1_CMSG_EXEC_SHELL
);
204 translate(SSH1_CMSG_EXEC_CMD
);
205 translate(SSH1_SMSG_SUCCESS
);
206 translate(SSH1_SMSG_FAILURE
);
207 translate(SSH1_CMSG_STDIN_DATA
);
208 translate(SSH1_SMSG_STDOUT_DATA
);
209 translate(SSH1_SMSG_STDERR_DATA
);
210 translate(SSH1_CMSG_EOF
);
211 translate(SSH1_SMSG_EXIT_STATUS
);
212 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
213 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
214 translate(SSH1_MSG_CHANNEL_DATA
);
215 translate(SSH1_MSG_CHANNEL_CLOSE
);
216 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
217 translate(SSH1_SMSG_X11_OPEN
);
218 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
219 translate(SSH1_MSG_PORT_OPEN
);
220 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
221 translate(SSH1_SMSG_AGENT_OPEN
);
222 translate(SSH1_MSG_IGNORE
);
223 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
224 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
225 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
226 translate(SSH1_MSG_DEBUG
);
227 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
228 translate(SSH1_CMSG_AUTH_TIS
);
229 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
230 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
231 translate(SSH1_CMSG_AUTH_CCARD
);
232 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
233 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
236 char *ssh2_pkt_type(int type
)
238 translate(SSH2_MSG_DISCONNECT
);
239 translate(SSH2_MSG_IGNORE
);
240 translate(SSH2_MSG_UNIMPLEMENTED
);
241 translate(SSH2_MSG_DEBUG
);
242 translate(SSH2_MSG_SERVICE_REQUEST
);
243 translate(SSH2_MSG_SERVICE_ACCEPT
);
244 translate(SSH2_MSG_KEXINIT
);
245 translate(SSH2_MSG_NEWKEYS
);
246 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
247 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
248 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
249 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
250 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
251 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
252 translate(SSH2_MSG_USERAUTH_REQUEST
);
253 translate(SSH2_MSG_USERAUTH_FAILURE
);
254 translate(SSH2_MSG_USERAUTH_SUCCESS
);
255 translate(SSH2_MSG_USERAUTH_BANNER
);
256 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
257 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
258 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
259 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
260 translate(SSH2_MSG_GLOBAL_REQUEST
);
261 translate(SSH2_MSG_REQUEST_SUCCESS
);
262 translate(SSH2_MSG_REQUEST_FAILURE
);
263 translate(SSH2_MSG_CHANNEL_OPEN
);
264 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
265 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
266 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
267 translate(SSH2_MSG_CHANNEL_DATA
);
268 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
269 translate(SSH2_MSG_CHANNEL_EOF
);
270 translate(SSH2_MSG_CHANNEL_CLOSE
);
271 translate(SSH2_MSG_CHANNEL_REQUEST
);
272 translate(SSH2_MSG_CHANNEL_SUCCESS
);
273 translate(SSH2_MSG_CHANNEL_FAILURE
);
279 #define GET_32BIT(cp) \
280 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
281 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
282 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
283 ((unsigned long)(unsigned char)(cp)[3]))
285 #define PUT_32BIT(cp, value) { \
286 (cp)[0] = (unsigned char)((value) >> 24); \
287 (cp)[1] = (unsigned char)((value) >> 16); \
288 (cp)[2] = (unsigned char)((value) >> 8); \
289 (cp)[3] = (unsigned char)(value); }
291 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
293 /* Coroutine mechanics for the sillier bits of the code */
294 #define crBegin1 static int crLine = 0;
295 #define crBegin2 switch(crLine) { case 0:;
296 #define crBegin crBegin1; crBegin2;
297 #define crFinish(z) } crLine = 0; return (z)
298 #define crFinishV } crLine = 0; return
299 #define crReturn(z) \
301 crLine=__LINE__; return (z); case __LINE__:;\
305 crLine=__LINE__; return; case __LINE__:;\
307 #define crStop(z) do{ crLine = 0; return (z); }while(0)
308 #define crStopV do{ crLine = 0; return; }while(0)
309 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
310 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
312 extern char *x11_init(Socket
*, char *, void *);
313 extern void x11_close(Socket
);
314 extern int x11_send(Socket
, char *, int);
315 extern void x11_invent_auth(char *, int, char *, int);
316 extern void x11_unthrottle(Socket s
);
317 extern void x11_override_throttle(Socket s
, int enable
);
319 extern char *pfd_newconnect(Socket
* s
, char *hostname
, int port
, void *c
);
320 extern char *pfd_addforward(char *desthost
, int destport
, int port
);
321 extern void pfd_close(Socket s
);
322 extern int pfd_send(Socket s
, char *data
, int len
);
323 extern void pfd_confirm(Socket s
);
324 extern void pfd_unthrottle(Socket s
);
325 extern void pfd_override_throttle(Socket s
, int enable
);
327 static void ssh2_pkt_init(int pkt_type
);
328 static void ssh2_pkt_addbool(unsigned char value
);
329 static void ssh2_pkt_adduint32(unsigned long value
);
330 static void ssh2_pkt_addstring_start(void);
331 static void ssh2_pkt_addstring_str(char *data
);
332 static void ssh2_pkt_addstring_data(char *data
, int len
);
333 static void ssh2_pkt_addstring(char *data
);
334 static char *ssh2_mpint_fmt(Bignum b
, int *len
);
335 static void ssh2_pkt_addmp(Bignum b
);
336 static int ssh2_pkt_construct(void);
337 static void ssh2_pkt_send(void);
340 * Buffer management constants. There are several of these for
341 * various different purposes:
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
360 #define SSH1_BUFFER_LIMIT 32768
361 #define SSH_MAX_BACKLOG 32768
362 #define OUR_V2_WINSIZE 16384
364 const static struct ssh_kex
*kex_algs
[] = {
365 &ssh_diffiehellman_gex
,
369 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
371 static void nullmac_key(unsigned char *key
)
374 static void nullmac_generate(unsigned char *blk
, int len
,
378 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
)
382 const static struct ssh_mac ssh_mac_none
= {
383 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
385 const static struct ssh_mac
*macs
[] = {
386 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
388 const static struct ssh_mac
*buggymacs
[] = {
389 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
392 static void ssh_comp_none_init(void)
395 static int ssh_comp_none_block(unsigned char *block
, int len
,
396 unsigned char **outblock
, int *outlen
)
400 static int ssh_comp_none_disable(void)
404 const static struct ssh_compress ssh_comp_none
= {
406 ssh_comp_none_init
, ssh_comp_none_block
,
407 ssh_comp_none_init
, ssh_comp_none_block
,
408 ssh_comp_none_disable
410 extern const struct ssh_compress ssh_zlib
;
411 const static struct ssh_compress
*compressions
[] = {
412 &ssh_zlib
, &ssh_comp_none
415 enum { /* channel types */
420 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
424 * 2-3-4 tree storing channels.
427 unsigned remoteid
, localid
;
430 * In SSH1, this value contains four bits:
432 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
433 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
434 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
435 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
437 * A channel is completely finished with when all four bits are set.
441 struct ssh1_data_channel
{
444 struct ssh2_data_channel
{
446 unsigned remwindow
, remmaxpkt
;
451 struct ssh_agent_channel
{
452 unsigned char *message
;
453 unsigned char msglen
[4];
454 int lensofar
, totallen
;
456 struct ssh_x11_channel
{
459 struct ssh_pfd_channel
{
466 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
467 * 2 use this structure in different ways, reflecting SSH 2's
468 * altogether saner approach to port forwarding.
470 * In SSH 1, you arrange a remote forwarding by sending the server
471 * the remote port number, and the local destination host:port.
472 * When a connection comes in, the server sends you back that
473 * host:port pair, and you connect to it. This is a ready-made
474 * security hole if you're not on the ball: a malicious server
475 * could send you back _any_ host:port pair, so if you trustingly
476 * connect to the address it gives you then you've just opened the
477 * entire inside of your corporate network just by connecting
478 * through it to a dodgy SSH server. Hence, we must store a list of
479 * host:port pairs we _are_ trying to forward to, and reject a
480 * connection request from the server if it's not in the list.
482 * In SSH 2, each side of the connection minds its own business and
483 * doesn't send unnecessary information to the other. You arrange a
484 * remote forwarding by sending the server just the remote port
485 * number. When a connection comes in, the server tells you which
486 * of its ports was connected to; and _you_ have to remember what
487 * local host:port pair went with that port number.
489 * Hence: in SSH 1 this structure stores host:port pairs we intend
490 * to allow connections to, and is indexed by those host:port
491 * pairs. In SSH 2 it stores a mapping from source port to
492 * destination host:port pair, and is indexed by source port.
494 struct ssh_rportfwd
{
495 unsigned sport
, dport
;
508 static SHA_State exhash
, exhashbase
;
510 static Socket s
= NULL
;
512 static unsigned char session_key
[32];
513 static int ssh1_compressing
;
514 static int ssh1_remote_protoflags
;
515 static int ssh1_local_protoflags
;
516 static int ssh_agentfwd_enabled
;
517 static int ssh_X11_fwd_enabled
;
518 static int ssh_remote_bugs
;
519 static const struct ssh_cipher
*cipher
= NULL
;
520 static const struct ssh2_cipher
*cscipher
= NULL
;
521 static const struct ssh2_cipher
*sccipher
= NULL
;
522 static const struct ssh_mac
*csmac
= NULL
;
523 static const struct ssh_mac
*scmac
= NULL
;
524 static const struct ssh_compress
*cscomp
= NULL
;
525 static const struct ssh_compress
*sccomp
= NULL
;
526 static const struct ssh_kex
*kex
= NULL
;
527 static const struct ssh_signkey
*hostkey
= NULL
;
528 static unsigned char ssh2_session_id
[20];
530 static char *savedhost
;
531 static int savedport
;
532 static int ssh_send_ok
;
533 static int ssh_echoing
, ssh_editing
;
535 static tree234
*ssh_channels
; /* indexed by local id */
536 static struct ssh_channel
*mainchan
; /* primary session channel */
537 static int ssh_exitcode
= -1;
539 static tree234
*ssh_rportfwds
;
543 SSH_STATE_BEFORE_SIZE
,
547 } ssh_state
= SSH_STATE_PREPACKET
;
549 static int size_needed
= FALSE
, eof_needed
= FALSE
;
551 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
552 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
553 static unsigned char *deferred_send_data
= NULL
;
554 static int deferred_len
= 0, deferred_size
= 0;
557 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
558 * that fails. This variable is the means by which scp.c can reach
559 * into the SSH code and find out which one it got.
561 int ssh_fallback_cmd
= 0;
563 static int ssh_version
;
564 static int ssh1_throttle_count
;
565 static int ssh_overall_bufsize
;
566 static int ssh_throttled_all
;
567 static int ssh1_stdout_throttling
;
568 static void (*ssh_protocol
) (unsigned char *in
, int inlen
, int ispkt
);
569 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
570 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
571 static void ssh_size(void);
572 static void ssh_special(Telnet_Special
);
573 static int ssh2_try_send(struct ssh_channel
*c
);
574 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
576 static void ssh_throttle_all(int enable
, int bufsize
);
577 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
578 static int (*s_rdpkt
) (unsigned char **data
, int *datalen
);
579 static int ssh_sendbuffer(void);
581 static struct rdpkt1_state_tag
{
582 long len
, pad
, biglen
, to_read
;
583 unsigned long realcrc
, gotcrc
;
589 static struct rdpkt2_state_tag
{
590 long len
, pad
, payload
, packetlen
, maclen
;
593 unsigned long incoming_sequence
;
596 static int ssh_channelcmp(void *av
, void *bv
)
598 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
599 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
600 if (a
->localid
< b
->localid
)
602 if (a
->localid
> b
->localid
)
606 static int ssh_channelfind(void *av
, void *bv
)
608 unsigned *a
= (unsigned *) av
;
609 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
617 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
619 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
620 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
622 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
623 return i
< 0 ?
-1 : +1;
624 if (a
->dport
> b
->dport
)
626 if (a
->dport
< b
->dport
)
631 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
633 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
634 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
636 if (a
->sport
> b
->sport
)
638 if (a
->sport
< b
->sport
)
643 static int alloc_channel_id(void)
645 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
646 unsigned low
, high
, mid
;
648 struct ssh_channel
*c
;
651 * First-fit allocation of channel numbers: always pick the
652 * lowest unused one. To do this, binary-search using the
653 * counted B-tree to find the largest channel ID which is in a
654 * contiguous sequence from the beginning. (Precisely
655 * everything in that sequence must have ID equal to its tree
656 * index plus CHANNEL_NUMBER_OFFSET.)
658 tsize
= count234(ssh_channels
);
662 while (high
- low
> 1) {
663 mid
= (high
+ low
) / 2;
664 c
= index234(ssh_channels
, mid
);
665 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
666 low
= mid
; /* this one is fine */
668 high
= mid
; /* this one is past it */
671 * Now low points to either -1, or the tree index of the
672 * largest ID in the initial sequence.
675 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
676 assert(NULL
== find234(ssh_channels
, &i
, ssh_channelfind
));
678 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
681 static void c_write(char *buf
, int len
)
683 if ((flags
& FLAG_STDERR
)) {
685 for (i
= 0; i
< len
; i
++)
687 fputc(buf
[i
], stderr
);
690 from_backend(1, buf
, len
);
693 static void c_write_untrusted(char *buf
, int len
)
696 for (i
= 0; i
< len
; i
++) {
699 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
704 static void c_write_str(char *buf
)
706 c_write(buf
, strlen(buf
));
710 * Collect incoming data in the incoming packet buffer.
711 * Decipher and verify the packet when it is completely read.
712 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
713 * Update the *data and *datalen variables.
714 * Return the additional nr of bytes needed, or 0 when
715 * a complete packet is available.
717 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
719 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
728 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
729 while ((*datalen
) == 0)
731 st
->len
= (st
->len
<< 8) + **data
;
732 (*data
)++, (*datalen
)--;
735 st
->pad
= 8 - (st
->len
% 8);
736 st
->biglen
= st
->len
+ st
->pad
;
737 pktin
.length
= st
->len
- 5;
739 if (pktin
.maxlen
< st
->biglen
) {
740 pktin
.maxlen
= st
->biglen
;
741 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+ APIEXTRA
) :
742 srealloc(pktin
.data
, st
->biglen
+ APIEXTRA
));
744 fatalbox("Out of memory");
747 st
->to_read
= st
->biglen
;
749 while (st
->to_read
> 0) {
750 st
->chunk
= st
->to_read
;
751 while ((*datalen
) == 0)
752 crReturn(st
->to_read
);
753 if (st
->chunk
> (*datalen
))
754 st
->chunk
= (*datalen
);
755 memcpy(st
->p
, *data
, st
->chunk
);
757 *datalen
-= st
->chunk
;
759 st
->to_read
-= st
->chunk
;
762 if (cipher
&& detect_attack(pktin
.data
, st
->biglen
, NULL
)) {
763 bombout(("Network attack (CRC compensation) detected!"));
768 cipher
->decrypt(pktin
.data
, st
->biglen
);
770 st
->realcrc
= crc32(pktin
.data
, st
->biglen
- 4);
771 st
->gotcrc
= GET_32BIT(pktin
.data
+ st
->biglen
- 4);
772 if (st
->gotcrc
!= st
->realcrc
) {
773 bombout(("Incorrect CRC received on packet"));
777 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
779 if (ssh1_compressing
) {
780 unsigned char *decompblk
;
782 zlib_decompress_block(pktin
.body
- 1, pktin
.length
+ 1,
783 &decompblk
, &decomplen
);
785 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
786 pktin
.maxlen
= st
->pad
+ decomplen
;
787 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+ APIEXTRA
);
788 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
790 fatalbox("Out of memory");
793 memcpy(pktin
.body
- 1, decompblk
, decomplen
);
795 pktin
.length
= decomplen
- 1;
798 pktin
.type
= pktin
.body
[-1];
800 log_packet(PKT_INCOMING
, pktin
.type
, ssh1_pkt_type(pktin
.type
),
801 pktin
.body
, pktin
.length
);
803 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
804 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
805 pktin
.type
== SSH1_MSG_DEBUG
||
806 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
807 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
808 long stringlen
= GET_32BIT(pktin
.body
);
809 if (stringlen
+ 4 != pktin
.length
) {
810 bombout(("Received data packet with bogus string length"));
815 if (pktin
.type
== SSH1_MSG_DEBUG
) {
816 /* log debug message */
818 int stringlen
= GET_32BIT(pktin
.body
);
819 strcpy(buf
, "Remote debug message: ");
822 memcpy(buf
+ 8, pktin
.body
+ 4, stringlen
);
823 buf
[8 + stringlen
] = '\0';
826 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
831 if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
832 /* log reason code in disconnect message */
834 unsigned msglen
= GET_32BIT(pktin
.body
);
836 strcpy(buf
, "Remote sent disconnect: ");
837 nowlen
= strlen(buf
);
838 if (msglen
> sizeof(buf
) - nowlen
- 1)
839 msglen
= sizeof(buf
) - nowlen
- 1;
840 memcpy(buf
+ nowlen
, pktin
.body
+ 4, msglen
);
841 buf
[nowlen
+ msglen
] = '\0';
842 /* logevent(buf); (this is now done within the bombout macro) */
843 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
850 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
852 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
860 st
->cipherblk
= sccipher
->blksize
;
863 if (st
->cipherblk
< 8)
866 if (pktin
.maxlen
< st
->cipherblk
) {
867 pktin
.maxlen
= st
->cipherblk
;
870 NULL ?
smalloc(st
->cipherblk
+
871 APIEXTRA
) : srealloc(pktin
.data
,
875 fatalbox("Out of memory");
879 * Acquire and decrypt the first block of the packet. This will
880 * contain the length and padding details.
882 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
883 while ((*datalen
) == 0)
884 crReturn(st
->cipherblk
- st
->i
);
885 pktin
.data
[st
->i
] = *(*data
)++;
890 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
893 * Now get the length and padding figures.
895 st
->len
= GET_32BIT(pktin
.data
);
896 st
->pad
= pktin
.data
[4];
899 * _Completely_ silly lengths should be stomped on before they
900 * do us any more damage.
902 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
903 bombout(("Incoming packet was garbled on decryption"));
908 * This enables us to deduce the payload length.
910 st
->payload
= st
->len
- st
->pad
- 1;
912 pktin
.length
= st
->payload
+ 5;
915 * So now we can work out the total packet length.
917 st
->packetlen
= st
->len
+ 4;
918 st
->maclen
= scmac ? scmac
->len
: 0;
921 * Adjust memory allocation if packet is too big.
923 if (pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
924 pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
927 NULL ?
smalloc(pktin
.maxlen
+ APIEXTRA
) : srealloc(pktin
.data
,
932 fatalbox("Out of memory");
936 * Read and decrypt the remainder of the packet.
938 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
940 while ((*datalen
) == 0)
941 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
942 pktin
.data
[st
->i
] = *(*data
)++;
945 /* Decrypt everything _except_ the MAC. */
947 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
948 st
->packetlen
- st
->cipherblk
);
954 && !scmac
->verify(pktin
.data
, st
->len
+ 4,
955 st
->incoming_sequence
)) {
956 bombout(("Incorrect MAC received on packet"));
959 st
->incoming_sequence
++; /* whether or not we MACed */
962 * Decompress packet payload.
965 unsigned char *newpayload
;
967 if (sccomp
&& sccomp
->decompress(pktin
.data
+ 5, pktin
.length
- 5,
968 &newpayload
, &newlen
)) {
969 if (pktin
.maxlen
< newlen
+ 5) {
970 pktin
.maxlen
= newlen
+ 5;
973 NULL ?
smalloc(pktin
.maxlen
+
974 APIEXTRA
) : srealloc(pktin
.data
,
978 fatalbox("Out of memory");
980 pktin
.length
= 5 + newlen
;
981 memcpy(pktin
.data
+ 5, newpayload
, newlen
);
987 pktin
.type
= pktin
.data
[5];
989 log_packet(PKT_INCOMING
, pktin
.type
, ssh2_pkt_type(pktin
.type
),
990 pktin
.data
+6, pktin
.length
-6);
992 switch (pktin
.type
) {
994 * These packets we must handle instantly.
996 case SSH2_MSG_DISCONNECT
:
998 /* log reason code in disconnect message */
1000 int reason
= GET_32BIT(pktin
.data
+ 6);
1001 unsigned msglen
= GET_32BIT(pktin
.data
+ 10);
1003 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1004 sprintf(buf
, "Received disconnect message (%s)",
1005 ssh2_disconnect_reasons
[reason
]);
1007 sprintf(buf
, "Received disconnect message (unknown type %d)",
1011 strcpy(buf
, "Disconnection message text: ");
1012 nowlen
= strlen(buf
);
1013 if (msglen
> sizeof(buf
) - nowlen
- 1)
1014 msglen
= sizeof(buf
) - nowlen
- 1;
1015 memcpy(buf
+ nowlen
, pktin
.data
+ 14, msglen
);
1016 buf
[nowlen
+ msglen
] = '\0';
1018 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1020 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1021 ssh2_disconnect_reasons
[reason
] : "unknown",
1026 case SSH2_MSG_IGNORE
:
1028 case SSH2_MSG_DEBUG
:
1030 /* log the debug message */
1032 /* int display = pktin.body[6]; */
1033 int stringlen
= GET_32BIT(pktin
.data
+7);
1035 strcpy(buf
, "Remote debug message: ");
1036 prefix
= strlen(buf
);
1037 if (stringlen
> sizeof(buf
)-prefix
-1)
1038 stringlen
= sizeof(buf
)-prefix
-1;
1039 memcpy(buf
+ prefix
, pktin
.data
+ 11, stringlen
);
1040 buf
[prefix
+ stringlen
] = '\0';
1043 goto next_packet
; /* FIXME: print the debug message */
1046 * These packets we need do nothing about here.
1048 case SSH2_MSG_UNIMPLEMENTED
:
1049 case SSH2_MSG_SERVICE_REQUEST
:
1050 case SSH2_MSG_SERVICE_ACCEPT
:
1051 case SSH2_MSG_KEXINIT
:
1052 case SSH2_MSG_NEWKEYS
:
1053 case SSH2_MSG_KEXDH_INIT
:
1054 case SSH2_MSG_KEXDH_REPLY
:
1055 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1056 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1057 case SSH2_MSG_KEX_DH_GEX_INIT
:
1058 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1059 case SSH2_MSG_USERAUTH_REQUEST
:
1060 case SSH2_MSG_USERAUTH_FAILURE
:
1061 case SSH2_MSG_USERAUTH_SUCCESS
:
1062 case SSH2_MSG_USERAUTH_BANNER
:
1063 case SSH2_MSG_USERAUTH_PK_OK
:
1064 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1065 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1066 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1067 case SSH2_MSG_GLOBAL_REQUEST
:
1068 case SSH2_MSG_REQUEST_SUCCESS
:
1069 case SSH2_MSG_REQUEST_FAILURE
:
1070 case SSH2_MSG_CHANNEL_OPEN
:
1071 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1072 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1073 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1074 case SSH2_MSG_CHANNEL_DATA
:
1075 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1076 case SSH2_MSG_CHANNEL_EOF
:
1077 case SSH2_MSG_CHANNEL_CLOSE
:
1078 case SSH2_MSG_CHANNEL_REQUEST
:
1079 case SSH2_MSG_CHANNEL_SUCCESS
:
1080 case SSH2_MSG_CHANNEL_FAILURE
:
1084 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1087 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
1088 ssh2_pkt_adduint32(st
->incoming_sequence
- 1);
1096 static void ssh1_pktout_size(int len
)
1100 len
+= 5; /* type and CRC */
1101 pad
= 8 - (len
% 8);
1104 pktout
.length
= len
- 5;
1105 if (pktout
.maxlen
< biglen
) {
1106 pktout
.maxlen
= biglen
;
1108 /* Allocate enough buffer space for extra block
1109 * for MS CryptEncrypt() */
1110 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 12) :
1111 srealloc(pktout
.data
, biglen
+ 12));
1113 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 4) :
1114 srealloc(pktout
.data
, biglen
+ 4));
1117 fatalbox("Out of memory");
1119 pktout
.body
= pktout
.data
+ 4 + pad
+ 1;
1122 static void s_wrpkt_start(int type
, int len
)
1124 ssh1_pktout_size(len
);
1128 static int s_wrpkt_prepare(void)
1130 int pad
, len
, biglen
, i
;
1133 pktout
.body
[-1] = pktout
.type
;
1135 log_packet(PKT_OUTGOING
, pktout
.type
, ssh1_pkt_type(pktout
.type
),
1136 pktout
.body
, pktout
.length
);
1138 if (ssh1_compressing
) {
1139 unsigned char *compblk
;
1141 zlib_compress_block(pktout
.body
- 1, pktout
.length
+ 1,
1142 &compblk
, &complen
);
1143 ssh1_pktout_size(complen
- 1);
1144 memcpy(pktout
.body
- 1, compblk
, complen
);
1148 len
= pktout
.length
+ 5; /* type and CRC */
1149 pad
= 8 - (len
% 8);
1152 for (i
= 0; i
< pad
; i
++)
1153 pktout
.data
[i
+ 4] = random_byte();
1154 crc
= crc32(pktout
.data
+ 4, biglen
- 4);
1155 PUT_32BIT(pktout
.data
+ biglen
, crc
);
1156 PUT_32BIT(pktout
.data
, len
);
1159 cipher
->encrypt(pktout
.data
+ 4, biglen
);
1164 static void s_wrpkt(void)
1167 len
= s_wrpkt_prepare();
1168 backlog
= sk_write(s
, pktout
.data
, len
);
1169 if (backlog
> SSH_MAX_BACKLOG
)
1170 ssh_throttle_all(1, backlog
);
1173 static void s_wrpkt_defer(void)
1176 len
= s_wrpkt_prepare();
1177 if (deferred_len
+ len
> deferred_size
) {
1178 deferred_size
= deferred_len
+ len
+ 128;
1179 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1181 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1182 deferred_len
+= len
;
1186 * Construct a packet with the specified contents.
1188 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
1190 unsigned char *p
, *argp
, argchar
;
1191 unsigned long argint
;
1192 int pktlen
, argtype
, arglen
;
1196 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1199 (void) va_arg(ap1
, int);
1203 (void) va_arg(ap1
, char);
1207 (void) va_arg(ap1
, unsigned char *);
1208 arglen
= va_arg(ap1
, int);
1212 argp
= va_arg(ap1
, unsigned char *);
1213 arglen
= strlen(argp
);
1214 pktlen
+= 4 + arglen
;
1217 bn
= va_arg(ap1
, Bignum
);
1218 pktlen
+= ssh1_bignum_length(bn
);
1225 s_wrpkt_start(pkttype
, pktlen
);
1228 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1231 argint
= va_arg(ap2
, int);
1232 PUT_32BIT(p
, argint
);
1236 argchar
= va_arg(ap2
, unsigned char);
1241 argp
= va_arg(ap2
, unsigned char *);
1242 arglen
= va_arg(ap2
, int);
1243 memcpy(p
, argp
, arglen
);
1247 argp
= va_arg(ap2
, unsigned char *);
1248 arglen
= strlen(argp
);
1249 PUT_32BIT(p
, arglen
);
1250 memcpy(p
+ 4, argp
, arglen
);
1254 bn
= va_arg(ap2
, Bignum
);
1255 p
+= ssh1_write_bignum(p
, bn
);
1261 static void send_packet(int pkttype
, ...)
1264 va_start(ap1
, pkttype
);
1265 va_start(ap2
, pkttype
);
1266 construct_packet(pkttype
, ap1
, ap2
);
1270 static void defer_packet(int pkttype
, ...)
1273 va_start(ap1
, pkttype
);
1274 va_start(ap2
, pkttype
);
1275 construct_packet(pkttype
, ap1
, ap2
);
1279 static int ssh_versioncmp(char *a
, char *b
)
1282 unsigned long av
, bv
;
1284 av
= strtoul(a
, &ae
, 10);
1285 bv
= strtoul(b
, &be
, 10);
1287 return (av
< bv ?
-1 : +1);
1292 av
= strtoul(ae
, &ae
, 10);
1293 bv
= strtoul(be
, &be
, 10);
1295 return (av
< bv ?
-1 : +1);
1301 * Utility routines for putting an SSH-protocol `string' and
1302 * `uint32' into a SHA state.
1305 static void sha_string(SHA_State
* s
, void *str
, int len
)
1307 unsigned char lenblk
[4];
1308 PUT_32BIT(lenblk
, len
);
1309 SHA_Bytes(s
, lenblk
, 4);
1310 SHA_Bytes(s
, str
, len
);
1313 static void sha_uint32(SHA_State
* s
, unsigned i
)
1315 unsigned char intblk
[4];
1316 PUT_32BIT(intblk
, i
);
1317 SHA_Bytes(s
, intblk
, 4);
1321 * SSH2 packet construction functions.
1323 static void ssh2_pkt_ensure(int length
)
1325 if (pktout
.maxlen
< length
) {
1326 pktout
.maxlen
= length
+ 256;
1329 NULL ?
smalloc(pktout
.maxlen
+
1330 APIEXTRA
) : srealloc(pktout
.data
,
1334 fatalbox("Out of memory");
1337 static void ssh2_pkt_adddata(void *data
, int len
)
1339 pktout
.length
+= len
;
1340 ssh2_pkt_ensure(pktout
.length
);
1341 memcpy(pktout
.data
+ pktout
.length
- len
, data
, len
);
1343 static void ssh2_pkt_addbyte(unsigned char byte
)
1345 ssh2_pkt_adddata(&byte
, 1);
1347 static void ssh2_pkt_init(int pkt_type
)
1350 ssh2_pkt_addbyte((unsigned char) pkt_type
);
1352 static void ssh2_pkt_addbool(unsigned char value
)
1354 ssh2_pkt_adddata(&value
, 1);
1356 static void ssh2_pkt_adduint32(unsigned long value
)
1359 PUT_32BIT(x
, value
);
1360 ssh2_pkt_adddata(x
, 4);
1362 static void ssh2_pkt_addstring_start(void)
1364 ssh2_pkt_adduint32(0);
1365 pktout
.savedpos
= pktout
.length
;
1367 static void ssh2_pkt_addstring_str(char *data
)
1369 ssh2_pkt_adddata(data
, strlen(data
));
1370 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1371 pktout
.length
- pktout
.savedpos
);
1373 static void ssh2_pkt_addstring_data(char *data
, int len
)
1375 ssh2_pkt_adddata(data
, len
);
1376 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1377 pktout
.length
- pktout
.savedpos
);
1379 static void ssh2_pkt_addstring(char *data
)
1381 ssh2_pkt_addstring_start();
1382 ssh2_pkt_addstring_str(data
);
1384 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1387 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1390 fatalbox("out of memory");
1392 for (i
= 1; i
<= n
; i
++)
1393 p
[i
] = bignum_byte(b
, n
- i
);
1395 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1397 memmove(p
, p
+ i
, n
+ 1 - i
);
1401 static void ssh2_pkt_addmp(Bignum b
)
1405 p
= ssh2_mpint_fmt(b
, &len
);
1406 ssh2_pkt_addstring_start();
1407 ssh2_pkt_addstring_data(p
, len
);
1412 * Construct an SSH2 final-form packet: compress it, encrypt it,
1413 * put the MAC on it. Final packet, ready to be sent, is stored in
1414 * pktout.data. Total length is returned.
1416 static int ssh2_pkt_construct(void)
1418 int cipherblk
, maclen
, padding
, i
;
1419 static unsigned long outgoing_sequence
= 0;
1421 log_packet(PKT_OUTGOING
, pktout
.data
[5], ssh2_pkt_type(pktout
.data
[5]),
1422 pktout
.data
+ 6, pktout
.length
- 6);
1425 * Compress packet payload.
1428 unsigned char *newpayload
;
1430 if (cscomp
&& cscomp
->compress(pktout
.data
+ 5, pktout
.length
- 5,
1431 &newpayload
, &newlen
)) {
1433 ssh2_pkt_adddata(newpayload
, newlen
);
1439 * Add padding. At least four bytes, and must also bring total
1440 * length (minus MAC) up to a multiple of the block size.
1442 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
1443 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1446 (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1447 maclen
= csmac ? csmac
->len
: 0;
1448 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
1449 pktout
.data
[4] = padding
;
1450 for (i
= 0; i
< padding
; i
++)
1451 pktout
.data
[pktout
.length
+ i
] = random_byte();
1452 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
1454 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
1456 outgoing_sequence
++; /* whether or not we MACed */
1459 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
1461 /* Ready-to-send packet starts at pktout.data. We return length. */
1462 return pktout
.length
+ padding
+ maclen
;
1466 * Construct and send an SSH2 packet immediately.
1468 static void ssh2_pkt_send(void)
1472 len
= ssh2_pkt_construct();
1473 backlog
= sk_write(s
, pktout
.data
, len
);
1474 if (backlog
> SSH_MAX_BACKLOG
)
1475 ssh_throttle_all(1, backlog
);
1479 * Construct an SSH2 packet and add it to a deferred data block.
1480 * Useful for sending multiple packets in a single sk_write() call,
1481 * to prevent a traffic-analysing listener from being able to work
1482 * out the length of any particular packet (such as the password
1485 * Note that because SSH2 sequence-numbers its packets, this can
1486 * NOT be used as an m4-style `defer' allowing packets to be
1487 * constructed in one order and sent in another.
1489 static void ssh2_pkt_defer(void)
1491 int len
= ssh2_pkt_construct();
1492 if (deferred_len
+ len
> deferred_size
) {
1493 deferred_size
= deferred_len
+ len
+ 128;
1494 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1496 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1497 deferred_len
+= len
;
1501 * Send the whole deferred data block constructed by
1502 * ssh2_pkt_defer() or SSH1's defer_packet().
1504 static void ssh_pkt_defersend(void)
1507 backlog
= sk_write(s
, deferred_send_data
, deferred_len
);
1508 deferred_len
= deferred_size
= 0;
1509 sfree(deferred_send_data
);
1510 deferred_send_data
= NULL
;
1511 if (backlog
> SSH_MAX_BACKLOG
)
1512 ssh_throttle_all(1, backlog
);
1516 void bndebug(char *string
, Bignum b
)
1520 p
= ssh2_mpint_fmt(b
, &len
);
1521 debug(("%s", string
));
1522 for (i
= 0; i
< len
; i
++)
1523 debug((" %02x", p
[i
]));
1529 static void sha_mpint(SHA_State
* s
, Bignum b
)
1533 p
= ssh2_mpint_fmt(b
, &len
);
1534 sha_string(s
, p
, len
);
1539 * SSH2 packet decode functions.
1541 static unsigned long ssh2_pkt_getuint32(void)
1543 unsigned long value
;
1544 if (pktin
.length
- pktin
.savedpos
< 4)
1545 return 0; /* arrgh, no way to decline (FIXME?) */
1546 value
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1547 pktin
.savedpos
+= 4;
1550 static int ssh2_pkt_getbool(void)
1552 unsigned long value
;
1553 if (pktin
.length
- pktin
.savedpos
< 1)
1554 return 0; /* arrgh, no way to decline (FIXME?) */
1555 value
= pktin
.data
[pktin
.savedpos
] != 0;
1559 static void ssh2_pkt_getstring(char **p
, int *length
)
1563 if (pktin
.length
- pktin
.savedpos
< 4)
1565 *length
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1566 pktin
.savedpos
+= 4;
1567 if (pktin
.length
- pktin
.savedpos
< *length
)
1569 *p
= pktin
.data
+ pktin
.savedpos
;
1570 pktin
.savedpos
+= *length
;
1572 static Bignum
ssh2_pkt_getmp(void)
1578 ssh2_pkt_getstring(&p
, &length
);
1582 bombout(("internal error: Can't handle negative mpints"));
1585 b
= bignum_from_bytes(p
, length
);
1590 * Helper function to add an SSH2 signature blob to a packet.
1591 * Expects to be shown the public key blob as well as the signature
1592 * blob. Normally works just like ssh2_pkt_addstring, but will
1593 * fiddle with the signature packet if necessary for
1594 * BUG_SSH2_RSA_PADDING.
1596 static void ssh2_add_sigblob(void *pkblob_v
, int pkblob_len
,
1597 void *sigblob_v
, int sigblob_len
)
1599 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1600 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1602 /* dmemdump(pkblob, pkblob_len); */
1603 /* dmemdump(sigblob, sigblob_len); */
1606 * See if this is in fact an ssh-rsa signature and a buggy
1607 * server; otherwise we can just do this the easy way.
1609 if ((ssh_remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1610 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1611 int pos
, len
, siglen
;
1614 * Find the byte length of the modulus.
1617 pos
= 4+7; /* skip over "ssh-rsa" */
1618 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1619 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1620 pos
+= 4; /* find modulus itself */
1621 while (len
> 0 && pkblob
[pos
] == 0)
1623 /* debug(("modulus length is %d\n", len)); */
1626 * Now find the signature integer.
1628 pos
= 4+7; /* skip over "ssh-rsa" */
1629 siglen
= GET_32BIT(sigblob
+pos
);
1630 /* debug(("signature length is %d\n", siglen)); */
1632 if (len
!= siglen
) {
1633 unsigned char newlen
[4];
1634 ssh2_pkt_addstring_start();
1635 ssh2_pkt_addstring_data(sigblob
, pos
);
1636 /* dmemdump(sigblob, pos); */
1637 pos
+= 4; /* point to start of actual sig */
1638 PUT_32BIT(newlen
, len
);
1639 ssh2_pkt_addstring_data(newlen
, 4);
1640 /* dmemdump(newlen, 4); */
1642 while (len
-- > siglen
) {
1643 ssh2_pkt_addstring_data(newlen
, 1);
1644 /* dmemdump(newlen, 1); */
1646 ssh2_pkt_addstring_data(sigblob
+pos
, siglen
);
1647 /* dmemdump(sigblob+pos, siglen); */
1651 /* Otherwise fall through and do it the easy way. */
1654 ssh2_pkt_addstring_start();
1655 ssh2_pkt_addstring_data(sigblob
, sigblob_len
);
1659 * Examine the remote side's version string and compare it against
1660 * a list of known buggy implementations.
1662 static void ssh_detect_bugs(char *vstring
)
1664 char *imp
; /* pointer to implementation part */
1666 imp
+= strcspn(imp
, "-");
1668 imp
+= strcspn(imp
, "-");
1671 ssh_remote_bugs
= 0;
1673 if (cfg
.sshbug_ignore1
== BUG_ON
||
1674 (cfg
.sshbug_ignore1
== BUG_AUTO
&&
1675 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1676 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1677 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")))) {
1679 * These versions don't support SSH1_MSG_IGNORE, so we have
1680 * to use a different defence against password length
1683 ssh_remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1684 logevent("We believe remote version has SSH1 ignore bug");
1687 if (cfg
.sshbug_plainpw1
== BUG_ON
||
1688 (cfg
.sshbug_plainpw1
== BUG_AUTO
&&
1689 (!strcmp(imp
, "Cisco-1.25")))) {
1691 * These versions need a plain password sent; they can't
1692 * handle having a null and a random length of data after
1695 ssh_remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1696 logevent("We believe remote version needs a plain SSH1 password");
1699 if (cfg
.sshbug_rsa1
== BUG_ON
||
1700 (cfg
.sshbug_rsa1
== BUG_AUTO
&&
1701 (!strcmp(imp
, "Cisco-1.25")))) {
1703 * These versions apparently have no clue whatever about
1704 * RSA authentication and will panic and die if they see
1705 * an AUTH_RSA message.
1707 ssh_remote_bugs
|= BUG_CHOKES_ON_RSA
;
1708 logevent("We believe remote version can't handle RSA authentication");
1711 if (cfg
.sshbug_hmac2
== BUG_ON
||
1712 (cfg
.sshbug_hmac2
== BUG_AUTO
&&
1713 (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1714 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1715 !strncmp(imp
, "2.1 ", 4)))) {
1717 * These versions have the HMAC bug.
1719 ssh_remote_bugs
|= BUG_SSH2_HMAC
;
1720 logevent("We believe remote version has SSH2 HMAC bug");
1723 if (cfg
.sshbug_derivekey2
== BUG_ON
||
1724 (cfg
.sshbug_derivekey2
== BUG_AUTO
&&
1725 (!strncmp(imp
, "2.0.", 4)))) {
1727 * These versions have the key-derivation bug (failing to
1728 * include the literal shared secret in the hashes that
1729 * generate the keys).
1731 ssh_remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1732 logevent("We believe remote version has SSH2 key-derivation bug");
1735 if (cfg
.sshbug_rsapad2
== BUG_ON
||
1736 (cfg
.sshbug_rsapad2
== BUG_AUTO
&&
1737 ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1738 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')))){
1740 * These versions have the SSH2 RSA padding bug.
1742 ssh_remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1743 logevent("We believe remote version has SSH2 RSA padding bug");
1747 static int do_ssh_init(unsigned char c
)
1750 static char version
[10];
1751 static char *vstring
;
1752 static int vstrsize
;
1755 static int proto1
, proto2
;
1759 /* Search for the string "SSH-" in the input. */
1762 static const int transS
[] = { 1, 2, 2, 1 };
1763 static const int transH
[] = { 0, 0, 3, 0 };
1764 static const int transminus
[] = { 0, 0, 0, -1 };
1775 crReturn(1); /* get another character */
1779 vstring
= smalloc(vstrsize
);
1780 strcpy(vstring
, "SSH-");
1784 crReturn(1); /* get another char */
1785 if (vslen
>= vstrsize
- 1) {
1787 vstring
= srealloc(vstring
, vstrsize
);
1789 vstring
[vslen
++] = c
;
1794 } else if (i
< sizeof(version
) - 1)
1796 } else if (c
== '\n')
1800 ssh_agentfwd_enabled
= FALSE
;
1801 rdpkt2_state
.incoming_sequence
= 0;
1804 vlog
= smalloc(20 + vslen
);
1805 vstring
[strcspn (vstring
, "\r\n")] = '\0'; /* remove end-of-line chars */
1806 sprintf(vlog
, "Server version: %s", vstring
);
1808 ssh_detect_bugs(vstring
);
1812 * Decide which SSH protocol version to support.
1815 /* Anything strictly below "2.0" means protocol 1 is supported. */
1816 proto1
= ssh_versioncmp(version
, "2.0") < 0;
1817 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1818 proto2
= ssh_versioncmp(version
, "1.99") >= 0;
1820 if (cfg
.sshprot
== 0 && !proto1
) {
1821 bombout(("SSH protocol version 1 required by user but not provided by server"));
1824 if (cfg
.sshprot
== 3 && !proto2
) {
1825 bombout(("SSH protocol version 2 required by user but not provided by server"));
1829 if (proto2
&& (cfg
.sshprot
>= 2 || !proto1
)) {
1833 char verstring
[80], vlog
[100];
1834 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1835 SHA_Init(&exhashbase
);
1837 * Hash our version string and their version string.
1839 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1840 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1841 sprintf(vlog
, "We claim version: %s", verstring
);
1843 strcat(verstring
, "\n");
1844 logevent("Using SSH protocol version 2");
1845 sk_write(s
, verstring
, strlen(verstring
));
1846 ssh_protocol
= ssh2_protocol
;
1848 s_rdpkt
= ssh2_rdpkt
;
1853 char verstring
[80], vlog
[100];
1854 sprintf(verstring
, "SSH-%s-%s",
1855 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"),
1857 sprintf(vlog
, "We claim version: %s", verstring
);
1859 strcat(verstring
, "\n");
1861 logevent("Using SSH protocol version 1");
1862 sk_write(s
, verstring
, strlen(verstring
));
1863 ssh_protocol
= ssh1_protocol
;
1865 s_rdpkt
= ssh1_rdpkt
;
1867 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1874 static void ssh_gotdata(unsigned char *data
, int datalen
)
1879 * To begin with, feed the characters one by one to the
1880 * protocol initialisation / selection function do_ssh_init().
1881 * When that returns 0, we're done with the initial greeting
1882 * exchange and can move on to packet discipline.
1887 crReturnV
; /* more data please */
1888 ret
= do_ssh_init(*data
);
1896 * We emerge from that loop when the initial negotiation is
1897 * over and we have selected an s_rdpkt function. Now pass
1898 * everything to s_rdpkt, and then pass the resulting packets
1899 * to the proper protocol handler.
1904 while (datalen
> 0) {
1905 if (s_rdpkt(&data
, &datalen
) == 0) {
1906 if (ssh_state
== SSH_STATE_CLOSED
) {
1909 ssh_protocol(NULL
, 0, 1);
1910 if (ssh_state
== SSH_STATE_CLOSED
) {
1920 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1923 ssh_state
= SSH_STATE_CLOSED
;
1929 /* A socket error has occurred. */
1930 logevent(error_msg
);
1931 connection_fatal(error_msg
);
1933 /* Otherwise, the remote side closed the connection normally. */
1938 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1940 ssh_gotdata(data
, len
);
1941 if (ssh_state
== SSH_STATE_CLOSED
) {
1951 static void ssh_sent(Plug plug
, int bufsize
)
1954 * If the send backlog on the SSH socket itself clears, we
1955 * should unthrottle the whole world if it was throttled.
1957 if (bufsize
< SSH_MAX_BACKLOG
)
1958 ssh_throttle_all(0, bufsize
);
1962 * Connect to specified host and port.
1963 * Returns an error message, or NULL on success.
1964 * Also places the canonical host name into `realhost'. It must be
1965 * freed by the caller.
1967 static char *connect_to_host(char *host
, int port
, char **realhost
, int nodelay
)
1969 static struct plug_function_table fn_table
= {
1974 }, *fn_table_ptr
= &fn_table
;
1983 savedhost
= smalloc(1 + strlen(host
));
1985 fatalbox("Out of memory");
1986 strcpy(savedhost
, host
);
1989 port
= 22; /* default ssh port */
2004 sprintf(buf
, "Looking up host \"%.170s\"", host
);
2007 addr
= sk_namelookup(host
, realhost
);
2008 if ((err
= sk_addr_error(addr
)))
2012 *realhost
= strdup(FWhost
);
2019 char buf
[200], addrbuf
[100];
2020 sk_getaddr(addr
, addrbuf
, 100);
2021 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
2024 s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, &fn_table_ptr
);
2025 if ((err
= sk_socket_error(s
))) {
2031 sk_write(s
, "connect ", 8);
2032 sk_write(s
, FWhost
, strlen(FWhost
));
2035 sprintf(buf
, " %d\n", FWport
);
2036 sk_write(s
, buf
, strlen(buf
));
2044 * Throttle or unthrottle the SSH connection.
2046 static void ssh1_throttle(int adjust
)
2048 int old_count
= ssh1_throttle_count
;
2049 ssh1_throttle_count
+= adjust
;
2050 assert(ssh1_throttle_count
>= 0);
2051 if (ssh1_throttle_count
&& !old_count
) {
2052 sk_set_frozen(s
, 1);
2053 } else if (!ssh1_throttle_count
&& old_count
) {
2054 sk_set_frozen(s
, 0);
2059 * Throttle or unthrottle _all_ local data streams (for when sends
2060 * on the SSH connection itself back up).
2062 static void ssh_throttle_all(int enable
, int bufsize
)
2065 struct ssh_channel
*c
;
2067 if (enable
== ssh_throttled_all
)
2069 ssh_throttled_all
= enable
;
2070 ssh_overall_bufsize
= bufsize
;
2073 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
2075 case CHAN_MAINSESSION
:
2077 * This is treated separately, outside the switch.
2081 x11_override_throttle(c
->u
.x11
.s
, enable
);
2084 /* Agent channels require no buffer management. */
2087 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2094 * Username and password input, abstracted off into reusable
2095 * routines (hopefully even reusable between SSH1 and SSH2!).
2097 static char *ssh_userpass_input_buffer
;
2098 static int ssh_userpass_input_buflen
;
2099 static int ssh_userpass_input_bufpos
;
2100 static int ssh_userpass_input_echo
;
2102 /* Set up a username or password input loop on a given buffer. */
2103 void setup_userpass_input(char *buffer
, int buflen
, int echo
)
2105 ssh_userpass_input_buffer
= buffer
;
2106 ssh_userpass_input_buflen
= buflen
;
2107 ssh_userpass_input_bufpos
= 0;
2108 ssh_userpass_input_echo
= echo
;
2112 * Process some terminal data in the course of username/password
2113 * input. Returns >0 for success (line of input returned in
2114 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2115 * for inconclusive (keep waiting for more input please).
2117 int process_userpass_input(unsigned char *in
, int inlen
)
2122 switch (c
= *in
++) {
2125 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
] = 0;
2126 ssh_userpass_input_buffer
[ssh_userpass_input_buflen
-1] = 0;
2131 if (ssh_userpass_input_bufpos
> 0) {
2132 if (ssh_userpass_input_echo
)
2133 c_write_str("\b \b");
2134 ssh_userpass_input_bufpos
--;
2139 while (ssh_userpass_input_bufpos
> 0) {
2140 if (ssh_userpass_input_echo
)
2141 c_write_str("\b \b");
2142 ssh_userpass_input_bufpos
--;
2150 if (((c
>= ' ' && c
<= '~') ||
2151 ((unsigned char) c
>= 160))
2152 && ssh_userpass_input_bufpos
< ssh_userpass_input_buflen
-1) {
2153 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
++] = c
;
2154 if (ssh_userpass_input_echo
)
2164 * Handle the key exchange and user authentication phases.
2166 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
2170 static unsigned char *rsabuf
, *keystr1
, *keystr2
;
2171 unsigned char cookie
[8];
2172 struct RSAKey servkey
, hostkey
;
2173 struct MD5Context md5c
;
2174 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
2175 static int tried_publickey
, tried_agent
;
2176 static int tis_auth_refused
, ccard_auth_refused
;
2177 static unsigned char session_id
[16];
2178 static int cipher_type
;
2179 static char username
[100];
2180 static void *publickey_blob
;
2181 int publickey_bloblen
;
2188 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2189 bombout(("Public key packet not received"));
2193 logevent("Received public keys");
2195 memcpy(cookie
, pktin
.body
, 8);
2197 i
= makekey(pktin
.body
+ 8, &servkey
, &keystr1
, 0);
2198 j
= makekey(pktin
.body
+ 8 + i
, &hostkey
, &keystr2
, 0);
2201 * Log the host key fingerprint.
2205 logevent("Host key fingerprint is:");
2206 strcpy(logmsg
, " ");
2207 hostkey
.comment
= NULL
;
2208 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2209 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2213 ssh1_remote_protoflags
= GET_32BIT(pktin
.body
+ 8 + i
+ j
);
2214 supported_ciphers_mask
= GET_32BIT(pktin
.body
+ 12 + i
+ j
);
2215 supported_auths_mask
= GET_32BIT(pktin
.body
+ 16 + i
+ j
);
2217 ssh1_local_protoflags
=
2218 ssh1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2219 ssh1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2222 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
2223 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
2224 MD5Update(&md5c
, pktin
.body
, 8);
2225 MD5Final(session_id
, &md5c
);
2227 for (i
= 0; i
< 32; i
++)
2228 session_key
[i
] = random_byte();
2230 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2232 rsabuf
= smalloc(len
);
2234 fatalbox("Out of memory");
2237 * Verify the host key.
2241 * First format the key into a string.
2243 int len
= rsastr_len(&hostkey
);
2244 char fingerprint
[100];
2245 char *keystr
= smalloc(len
);
2247 fatalbox("Out of memory");
2248 rsastr_fmt(keystr
, &hostkey
);
2249 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2250 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
,
2255 for (i
= 0; i
< 32; i
++) {
2256 rsabuf
[i
] = session_key
[i
];
2258 rsabuf
[i
] ^= session_id
[i
];
2261 if (hostkey
.bytes
> servkey
.bytes
) {
2262 rsaencrypt(rsabuf
, 32, &servkey
);
2263 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
2265 rsaencrypt(rsabuf
, 32, &hostkey
);
2266 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
2269 logevent("Encrypted session key");
2272 int cipher_chosen
= 0, warn
= 0;
2273 char *cipher_string
= NULL
;
2274 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2275 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2276 if (next_cipher
== CIPHER_WARN
) {
2277 /* If/when we choose a cipher, warn about it */
2279 } else if (next_cipher
== CIPHER_AES
) {
2280 /* XXX Probably don't need to mention this. */
2281 logevent("AES not supported in SSH1, skipping");
2283 switch (next_cipher
) {
2284 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
;
2285 cipher_string
= "3DES"; break;
2286 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
;
2287 cipher_string
= "Blowfish"; break;
2288 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
;
2289 cipher_string
= "single-DES"; break;
2291 if (supported_ciphers_mask
& (1 << cipher_type
))
2295 if (!cipher_chosen
) {
2296 if ((supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2297 bombout(("Server violates SSH 1 protocol by not "
2298 "supporting 3DES encryption"));
2300 /* shouldn't happen */
2301 bombout(("No supported ciphers found"));
2305 /* Warn about chosen cipher if necessary. */
2307 askcipher(cipher_string
, 0);
2310 switch (cipher_type
) {
2311 case SSH_CIPHER_3DES
:
2312 logevent("Using 3DES encryption");
2314 case SSH_CIPHER_DES
:
2315 logevent("Using single-DES encryption");
2317 case SSH_CIPHER_BLOWFISH
:
2318 logevent("Using Blowfish encryption");
2322 send_packet(SSH1_CMSG_SESSION_KEY
,
2323 PKT_CHAR
, cipher_type
,
2324 PKT_DATA
, cookie
, 8,
2325 PKT_CHAR
, (len
* 8) >> 8, PKT_CHAR
, (len
* 8) & 0xFF,
2326 PKT_DATA
, rsabuf
, len
,
2327 PKT_INT
, ssh1_local_protoflags
, PKT_END
);
2329 logevent("Trying to enable encryption...");
2333 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2334 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
: &ssh_3des
;
2335 cipher
->sesskey(session_key
);
2339 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2340 bombout(("Encryption not successfully enabled"));
2344 logevent("Successfully started encryption");
2348 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2349 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2350 if (!ssh_get_line("login as: ",
2351 username
, sizeof(username
), FALSE
)) {
2353 * get_line failed to get a username.
2356 logevent("No username provided. Abandoning session.");
2357 ssh_state
= SSH_STATE_CLOSED
;
2362 c_write_str("login as: ");
2365 setup_userpass_input(username
, sizeof(username
), 1);
2367 crWaitUntil(!ispkt
);
2368 ret
= process_userpass_input(in
, inlen
);
2372 c_write_str("\r\n");
2375 strncpy(username
, cfg
.username
, sizeof(username
));
2376 username
[sizeof(username
)-1] = '\0';
2379 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
2381 char userlog
[22 + sizeof(username
)];
2382 sprintf(userlog
, "Sent username \"%s\"", username
);
2384 if (flags
& FLAG_INTERACTIVE
&&
2385 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2386 strcat(userlog
, "\r\n");
2387 c_write_str(userlog
);
2394 if ((ssh_remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2395 /* We must not attempt PK auth. Pretend we've already tried it. */
2396 tried_publickey
= tried_agent
= 1;
2398 tried_publickey
= tried_agent
= 0;
2400 tis_auth_refused
= ccard_auth_refused
= 0;
2401 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2403 if (!rsakey_pubblob(cfg
.keyfile
, &publickey_blob
, &publickey_bloblen
))
2404 publickey_blob
= NULL
;
2406 publickey_blob
= NULL
;
2408 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
2409 static char password
[100];
2410 static char prompt
[200];
2413 static int pwpkt_type
;
2414 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2416 if (agent_exists() && !tried_agent
) {
2418 * Attempt RSA authentication using Pageant.
2420 static unsigned char request
[5], *response
, *p
;
2421 static int responselen
;
2422 static int i
, nkeys
;
2423 static int authed
= FALSE
;
2427 logevent("Pageant is running. Requesting keys.");
2429 /* Request the keys held by the agent. */
2430 PUT_32BIT(request
, 1);
2431 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2432 agent_query(request
, 5, &r
, &responselen
);
2433 response
= (unsigned char *) r
;
2434 if (response
&& responselen
>= 5 &&
2435 response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2437 nkeys
= GET_32BIT(p
);
2441 sprintf(buf
, "Pageant has %d SSH1 keys", nkeys
);
2444 for (i
= 0; i
< nkeys
; i
++) {
2445 static struct RSAKey key
;
2446 static Bignum challenge
;
2447 static char *commentp
;
2448 static int commentlen
;
2452 sprintf(buf
, "Trying Pageant key #%d", i
);
2455 if (publickey_blob
&&
2456 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
2457 logevent("This key matches configured key file");
2458 tried_publickey
= 1;
2461 p
+= ssh1_read_bignum(p
, &key
.exponent
);
2462 p
+= ssh1_read_bignum(p
, &key
.modulus
);
2463 commentlen
= GET_32BIT(p
);
2467 send_packet(SSH1_CMSG_AUTH_RSA
,
2468 PKT_BIGNUM
, key
.modulus
, PKT_END
);
2470 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2471 logevent("Key refused");
2474 logevent("Received RSA challenge");
2475 ssh1_read_bignum(pktin
.body
, &challenge
);
2477 char *agentreq
, *q
, *ret
;
2480 len
= 1 + 4; /* message type, bit count */
2481 len
+= ssh1_bignum_length(key
.exponent
);
2482 len
+= ssh1_bignum_length(key
.modulus
);
2483 len
+= ssh1_bignum_length(challenge
);
2484 len
+= 16; /* session id */
2485 len
+= 4; /* response format */
2486 agentreq
= smalloc(4 + len
);
2487 PUT_32BIT(agentreq
, len
);
2489 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2490 PUT_32BIT(q
, bignum_bitcount(key
.modulus
));
2492 q
+= ssh1_write_bignum(q
, key
.exponent
);
2493 q
+= ssh1_write_bignum(q
, key
.modulus
);
2494 q
+= ssh1_write_bignum(q
, challenge
);
2495 memcpy(q
, session_id
, 16);
2497 PUT_32BIT(q
, 1); /* response format */
2498 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2502 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2503 logevent("Sending Pageant's response");
2504 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2505 PKT_DATA
, ret
+ 5, 16,
2509 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2511 ("Pageant's response accepted");
2512 if (flags
& FLAG_VERBOSE
) {
2514 ("Authenticated using RSA key \"");
2515 c_write(commentp
, commentlen
);
2516 c_write_str("\" from agent\r\n");
2521 ("Pageant's response not accepted");
2524 ("Pageant failed to answer challenge");
2528 logevent("No reply received from Pageant");
2531 freebn(key
.exponent
);
2532 freebn(key
.modulus
);
2541 if (*cfg
.keyfile
&& !tried_publickey
)
2542 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2544 if (cfg
.try_tis_auth
&&
2545 (supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2546 !tis_auth_refused
) {
2547 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2548 logevent("Requested TIS authentication");
2549 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
2551 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2552 logevent("TIS authentication declined");
2553 if (flags
& FLAG_INTERACTIVE
)
2554 c_write_str("TIS authentication refused.\r\n");
2555 tis_auth_refused
= 1;
2558 int challengelen
= ((pktin
.body
[0] << 24) |
2559 (pktin
.body
[1] << 16) |
2560 (pktin
.body
[2] << 8) |
2562 logevent("Received TIS challenge");
2563 if (challengelen
> sizeof(prompt
) - 1)
2564 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2565 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2566 /* Prompt heuristic comes from OpenSSH */
2567 strncpy(prompt
+ challengelen
,
2568 memchr(prompt
, '\n', challengelen
) ?
2569 "": "\r\nResponse: ",
2570 (sizeof prompt
) - challengelen
);
2571 prompt
[(sizeof prompt
) - 1] = '\0';
2574 if (cfg
.try_tis_auth
&&
2575 (supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2576 !ccard_auth_refused
) {
2577 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2578 logevent("Requested CryptoCard authentication");
2579 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2581 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2582 logevent("CryptoCard authentication declined");
2583 c_write_str("CryptoCard authentication refused.\r\n");
2584 ccard_auth_refused
= 1;
2587 int challengelen
= ((pktin
.body
[0] << 24) |
2588 (pktin
.body
[1] << 16) |
2589 (pktin
.body
[2] << 8) |
2591 logevent("Received CryptoCard challenge");
2592 if (challengelen
> sizeof(prompt
) - 1)
2593 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2594 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2595 strncpy(prompt
+ challengelen
,
2596 memchr(prompt
, '\n', challengelen
) ?
2597 "" : "\r\nResponse: ",
2598 sizeof(prompt
) - challengelen
);
2599 prompt
[sizeof(prompt
) - 1] = '\0';
2602 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2603 sprintf(prompt
, "%.90s@%.90s's password: ",
2604 username
, savedhost
);
2606 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2607 char *comment
= NULL
;
2610 if (flags
& FLAG_VERBOSE
)
2611 c_write_str("Trying public key authentication.\r\n");
2612 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2614 type
= key_type(cfg
.keyfile
);
2615 if (type
!= SSH_KEYTYPE_SSH1
) {
2616 sprintf(msgbuf
, "Key is of wrong type (%s)",
2617 key_type_to_str(type
));
2619 c_write_str(msgbuf
);
2620 c_write_str("\r\n");
2621 tried_publickey
= 1;
2624 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2625 if (flags
& FLAG_VERBOSE
)
2626 c_write_str("No passphrase required.\r\n");
2629 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
2634 * Show password prompt, having first obtained it via a TIS
2635 * or CryptoCard exchange if we're doing TIS or CryptoCard
2639 if (!ssh_get_line(prompt
, password
, sizeof(password
), TRUE
)) {
2641 * get_line failed to get a password (for example
2642 * because one was supplied on the command line
2643 * which has already failed to work). Terminate.
2645 send_packet(SSH1_MSG_DISCONNECT
,
2646 PKT_STR
, "No more passwords available to try",
2648 logevent("Unable to authenticate");
2649 connection_fatal("Unable to authenticate");
2650 ssh_state
= SSH_STATE_CLOSED
;
2654 /* Prompt may have come from server. We've munged it a bit, so
2655 * we know it to be zero-terminated at least once. */
2657 c_write_untrusted(prompt
, strlen(prompt
));
2660 setup_userpass_input(password
, sizeof(password
), 0);
2662 crWaitUntil(!ispkt
);
2663 ret
= process_userpass_input(in
, inlen
);
2667 c_write_str("\r\n");
2671 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2673 * Try public key authentication with the specified
2676 static struct RSAKey pubkey
;
2677 static Bignum challenge
, response
;
2679 static unsigned char buffer
[32];
2681 tried_publickey
= 1;
2682 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
2684 c_write_str("Couldn't load private key from ");
2685 c_write_str(cfg
.keyfile
);
2686 c_write_str(".\r\n");
2687 continue; /* go and try password */
2690 c_write_str("Wrong passphrase.\r\n");
2691 tried_publickey
= 0;
2692 continue; /* try again */
2696 * Send a public key attempt.
2698 send_packet(SSH1_CMSG_AUTH_RSA
,
2699 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
2702 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2703 c_write_str("Server refused our public key.\r\n");
2704 continue; /* go and try password */
2706 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2707 bombout(("Bizarre response to offer of public key"));
2710 ssh1_read_bignum(pktin
.body
, &challenge
);
2711 response
= rsadecrypt(challenge
, &pubkey
);
2712 freebn(pubkey
.private_exponent
); /* burn the evidence */
2714 for (i
= 0; i
< 32; i
++) {
2715 buffer
[i
] = bignum_byte(response
, 31 - i
);
2719 MD5Update(&md5c
, buffer
, 32);
2720 MD5Update(&md5c
, session_id
, 16);
2721 MD5Final(buffer
, &md5c
);
2723 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2724 PKT_DATA
, buffer
, 16, PKT_END
);
2727 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2728 if (flags
& FLAG_VERBOSE
)
2730 ("Failed to authenticate with our public key.\r\n");
2731 continue; /* go and try password */
2732 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2734 ("Bizarre response to RSA authentication response"));
2738 break; /* we're through! */
2740 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2742 * Defence against traffic analysis: we send a
2743 * whole bunch of packets containing strings of
2744 * different lengths. One of these strings is the
2745 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2746 * The others are all random data in
2747 * SSH1_MSG_IGNORE packets. This way a passive
2748 * listener can't tell which is the password, and
2749 * hence can't deduce the password length.
2751 * Anybody with a password length greater than 16
2752 * bytes is going to have enough entropy in their
2753 * password that a listener won't find it _that_
2754 * much help to know how long it is. So what we'll
2757 * - if password length < 16, we send 15 packets
2758 * containing string lengths 1 through 15
2760 * - otherwise, we let N be the nearest multiple
2761 * of 8 below the password length, and send 8
2762 * packets containing string lengths N through
2763 * N+7. This won't obscure the order of
2764 * magnitude of the password length, but it will
2765 * introduce a bit of extra uncertainty.
2767 * A few servers (the old 1.2.18 through 1.2.22)
2768 * can't deal with SSH1_MSG_IGNORE. For these
2769 * servers, we need an alternative defence. We make
2770 * use of the fact that the password is interpreted
2771 * as a C string: so we can append a NUL, then some
2774 * One server (a Cisco one) can deal with neither
2775 * SSH1_MSG_IGNORE _nor_ a padded password string.
2776 * For this server we are left with no defences
2777 * against password length sniffing.
2779 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2781 * The server can deal with SSH1_MSG_IGNORE, so
2782 * we can use the primary defence.
2784 int bottom
, top
, pwlen
, i
;
2787 pwlen
= strlen(password
);
2789 bottom
= 0; /* zero length passwords are OK! :-) */
2792 bottom
= pwlen
& ~7;
2796 assert(pwlen
>= bottom
&& pwlen
<= top
);
2798 randomstr
= smalloc(top
+ 1);
2800 for (i
= bottom
; i
<= top
; i
++) {
2802 defer_packet(pwpkt_type
, PKT_STR
, password
,
2805 for (j
= 0; j
< i
; j
++) {
2807 randomstr
[j
] = random_byte();
2808 } while (randomstr
[j
] == '\0');
2810 randomstr
[i
] = '\0';
2811 defer_packet(SSH1_MSG_IGNORE
,
2812 PKT_STR
, randomstr
, PKT_END
);
2815 logevent("Sending password with camouflage packets");
2816 ssh_pkt_defersend();
2818 else if (!(ssh_remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2820 * The server can't deal with SSH1_MSG_IGNORE
2821 * but can deal with padded passwords, so we
2822 * can use the secondary defence.
2828 len
= strlen(password
);
2829 if (len
< sizeof(string
)) {
2831 strcpy(string
, password
);
2832 len
++; /* cover the zero byte */
2833 while (len
< sizeof(string
)) {
2834 string
[len
++] = (char) random_byte();
2839 logevent("Sending length-padded password");
2840 send_packet(pwpkt_type
, PKT_INT
, len
,
2841 PKT_DATA
, s
, len
, PKT_END
);
2844 * The server has _both_
2845 * BUG_CHOKES_ON_SSH1_IGNORE and
2846 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2847 * therefore nothing we can do.
2850 len
= strlen(password
);
2851 logevent("Sending unpadded password");
2852 send_packet(pwpkt_type
, PKT_INT
, len
,
2853 PKT_DATA
, password
, len
, PKT_END
);
2856 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
2859 logevent("Sent password");
2860 memset(password
, 0, strlen(password
));
2862 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2863 if (flags
& FLAG_VERBOSE
)
2864 c_write_str("Access denied\r\n");
2865 logevent("Authentication refused");
2866 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2867 logevent("Received disconnect request");
2868 ssh_state
= SSH_STATE_CLOSED
;
2870 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2871 bombout(("Strange packet received, type %d", pktin
.type
));
2876 logevent("Authentication successful");
2881 void sshfwd_close(struct ssh_channel
*c
)
2883 if (c
&& !c
->closes
) {
2885 * If the channel's remoteid is -1, we have sent
2886 * CHANNEL_OPEN for this channel, but it hasn't even been
2887 * acknowledged by the server. So we must set a close flag
2888 * on it now, and then when the server acks the channel
2889 * open, we can close it then.
2891 if (((int)c
->remoteid
) != -1) {
2892 if (ssh_version
== 1) {
2893 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2896 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2897 ssh2_pkt_adduint32(c
->remoteid
);
2901 c
->closes
= 1; /* sent MSG_CLOSE */
2902 if (c
->type
== CHAN_X11
) {
2904 logevent("Forwarded X11 connection terminated");
2905 } else if (c
->type
== CHAN_SOCKDATA
||
2906 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2908 logevent("Forwarded port closed");
2913 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2915 if (ssh_version
== 1) {
2916 send_packet(SSH1_MSG_CHANNEL_DATA
,
2917 PKT_INT
, c
->remoteid
,
2918 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2920 * In SSH1 we can return 0 here - implying that forwarded
2921 * connections are never individually throttled - because
2922 * the only circumstance that can cause throttling will be
2923 * the whole SSH connection backing up, in which case
2924 * _everything_ will be throttled as a whole.
2928 ssh2_add_channel_data(c
, buf
, len
);
2929 return ssh2_try_send(c
);
2933 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2935 if (ssh_version
== 1) {
2936 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2937 c
->v
.v1
.throttling
= 0;
2941 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
2945 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
)
2951 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
2954 if (ssh_state
== SSH_STATE_CLOSED
)
2957 if (cfg
.agentfwd
&& agent_exists()) {
2958 logevent("Requesting agent forwarding");
2959 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
2963 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2964 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2965 bombout(("Protocol confusion"));
2967 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2968 logevent("Agent forwarding refused");
2970 logevent("Agent forwarding enabled");
2971 ssh_agentfwd_enabled
= TRUE
;
2975 if (cfg
.x11_forward
) {
2976 char proto
[20], data
[64];
2977 logevent("Requesting X11 forwarding");
2978 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2979 if (ssh1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
2980 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2981 PKT_STR
, proto
, PKT_STR
, data
,
2982 PKT_INT
, 0, PKT_END
);
2984 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2985 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
2990 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2991 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2992 bombout(("Protocol confusion"));
2994 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2995 logevent("X11 forwarding refused");
2997 logevent("X11 forwarding enabled");
2998 ssh_X11_fwd_enabled
= TRUE
;
3006 int sport
,dport
,sserv
,dserv
;
3007 char sports
[256], dports
[256], host
[256];
3011 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3012 /* Add port forwardings. */
3017 while (*e
&& *e
!= '\t')
3023 while (*e
&& *e
!= ':')
3033 dport
= atoi(dports
);
3037 se
= getservbyname(dports
, NULL
);
3039 dport
= ntohs(se
->s_port
);
3042 "Service lookup failed for destination port \"%s\"",
3047 sport
= atoi(sports
);
3051 se
= getservbyname(sports
, NULL
);
3053 sport
= ntohs(se
->s_port
);
3056 "Service lookup failed for source port \"%s\"",
3061 if (sport
&& dport
) {
3063 pfd_addforward(host
, dport
, sport
);
3064 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3065 " %s:%.*s%.*s%d%.*s",
3066 sserv ?
strlen(sports
) : 0, sports
,
3067 sserv
, "(", sport
, sserv
, ")",
3069 dserv ?
strlen(dports
) : 0, dports
,
3070 dserv
, "(", dport
, dserv
, ")");
3073 struct ssh_rportfwd
*pf
;
3074 pf
= smalloc(sizeof(*pf
));
3075 strcpy(pf
->dhost
, host
);
3077 if (add234(ssh_rportfwds
, pf
) != pf
) {
3079 "Duplicate remote port forwarding to %s:%d",
3084 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3085 " forward to %s:%.*s%.*s%d%.*s",
3086 sserv ?
strlen(sports
) : 0, sports
,
3087 sserv
, "(", sport
, sserv
, ")",
3089 dserv ?
strlen(dports
) : 0, dports
,
3090 dserv
, "(", dport
, dserv
, ")");
3092 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST
,
3100 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3101 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3102 bombout(("Protocol confusion"));
3104 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3105 c_write_str("Server refused port forwarding\r\n");
3106 ssh_editing
= ssh_echoing
= 1;
3108 logevent("Remote port forwarding enabled");
3116 send_packet(SSH1_CMSG_REQUEST_PTY
,
3117 PKT_STR
, cfg
.termtype
,
3118 PKT_INT
, rows
, PKT_INT
, cols
,
3119 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3120 ssh_state
= SSH_STATE_INTERMED
;
3124 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3125 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3126 bombout(("Protocol confusion"));
3128 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3129 c_write_str("Server refused to allocate pty\r\n");
3130 ssh_editing
= ssh_echoing
= 1;
3132 logevent("Allocated pty");
3134 ssh_editing
= ssh_echoing
= 1;
3137 if (cfg
.compression
) {
3138 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3142 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3143 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3144 bombout(("Protocol confusion"));
3146 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3147 c_write_str("Server refused to compress\r\n");
3149 logevent("Started compression");
3150 ssh1_compressing
= TRUE
;
3151 zlib_compress_init();
3152 zlib_decompress_init();
3156 * Start the shell or command.
3158 * Special case: if the first-choice command is an SSH2
3159 * subsystem (hence not usable here) and the second choice
3160 * exists, we fall straight back to that.
3163 char *cmd
= cfg
.remote_cmd_ptr
;
3165 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3166 cmd
= cfg
.remote_cmd_ptr2
;
3167 ssh_fallback_cmd
= TRUE
;
3170 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3172 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3173 logevent("Started session");
3176 ssh_state
= SSH_STATE_SESSION
;
3180 ssh_special(TS_EOF
);
3182 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
3184 ssh_channels
= newtree234(ssh_channelcmp
);
3188 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3189 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3190 long len
= GET_32BIT(pktin
.body
);
3192 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3193 pktin
.body
+ 4, len
);
3194 if (!ssh1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3195 ssh1_stdout_throttling
= 1;
3198 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
3199 ssh_state
= SSH_STATE_CLOSED
;
3200 logevent("Received disconnect request");
3202 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3203 /* Remote side is trying to open a channel to talk to our
3204 * X-Server. Give them back a local channel number. */
3205 struct ssh_channel
*c
;
3207 logevent("Received X11 connect request");
3208 /* Refuse if X11 forwarding is disabled. */
3209 if (!ssh_X11_fwd_enabled
) {
3210 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3211 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3212 logevent("Rejected X11 connect request");
3214 c
= smalloc(sizeof(struct ssh_channel
));
3216 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3217 logevent("opening X11 forward connection failed");
3219 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3220 PKT_INT
, GET_32BIT(pktin
.body
),
3224 ("opening X11 forward connection succeeded");
3225 c
->remoteid
= GET_32BIT(pktin
.body
);
3226 c
->localid
= alloc_channel_id();
3228 c
->v
.v1
.throttling
= 0;
3229 c
->type
= CHAN_X11
; /* identify channel type */
3230 add234(ssh_channels
, c
);
3231 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3232 PKT_INT
, c
->remoteid
, PKT_INT
,
3233 c
->localid
, PKT_END
);
3234 logevent("Opened X11 forward channel");
3237 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3238 /* Remote side is trying to open a channel to talk to our
3239 * agent. Give them back a local channel number. */
3240 struct ssh_channel
*c
;
3242 /* Refuse if agent forwarding is disabled. */
3243 if (!ssh_agentfwd_enabled
) {
3244 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3245 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3247 c
= smalloc(sizeof(struct ssh_channel
));
3248 c
->remoteid
= GET_32BIT(pktin
.body
);
3249 c
->localid
= alloc_channel_id();
3251 c
->v
.v1
.throttling
= 0;
3252 c
->type
= CHAN_AGENT
; /* identify channel type */
3253 c
->u
.a
.lensofar
= 0;
3254 add234(ssh_channels
, c
);
3255 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3256 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3259 } else if (pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3260 /* Remote side is trying to open a channel to talk to a
3261 * forwarded port. Give them back a local channel number. */
3262 struct ssh_channel
*c
;
3263 struct ssh_rportfwd pf
;
3265 char host
[256], buf
[1024];
3267 c
= smalloc(sizeof(struct ssh_channel
));
3269 hostsize
= GET_32BIT(pktin
.body
+4);
3270 for(h
= host
, p
= pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3271 if (h
+1 < host
+sizeof(host
))
3276 port
= GET_32BIT(p
);
3278 strcpy(pf
.dhost
, host
);
3281 if (find234(ssh_rportfwds
, &pf
, NULL
) == NULL
) {
3282 sprintf(buf
, "Rejected remote port open request for %s:%d",
3285 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3286 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3288 sprintf(buf
, "Received remote port open request for %s:%d",
3291 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3294 sprintf(buf
, "Port open failed: %s", e
);
3297 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3298 PKT_INT
, GET_32BIT(pktin
.body
),
3301 c
->remoteid
= GET_32BIT(pktin
.body
);
3302 c
->localid
= alloc_channel_id();
3304 c
->v
.v1
.throttling
= 0;
3305 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3306 add234(ssh_channels
, c
);
3307 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3308 PKT_INT
, c
->remoteid
, PKT_INT
,
3309 c
->localid
, PKT_END
);
3310 logevent("Forwarded port opened successfully");
3314 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3315 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3316 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3317 struct ssh_channel
*c
;
3319 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3320 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3321 c
->remoteid
= localid
;
3322 c
->type
= CHAN_SOCKDATA
;
3323 c
->v
.v1
.throttling
= 0;
3324 pfd_confirm(c
->u
.pfd
.s
);
3327 if (c
&& c
->closes
) {
3329 * We have a pending close on this channel,
3330 * which we decided on before the server acked
3331 * the channel open. So now we know the
3332 * remoteid, we can close it again.
3334 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3338 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3339 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3340 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3341 struct ssh_channel
*c
;
3343 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3344 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3345 logevent("Forwarded connection refused by server");
3346 pfd_close(c
->u
.pfd
.s
);
3347 del234(ssh_channels
, c
);
3351 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3352 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3353 /* Remote side closes a channel. */
3354 unsigned i
= GET_32BIT(pktin
.body
);
3355 struct ssh_channel
*c
;
3356 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3357 if (c
&& ((int)c
->remoteid
) != -1) {
3360 (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3362 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3363 logevent("Forwarded X11 connection terminated");
3364 assert(c
->u
.x11
.s
!= NULL
);
3365 x11_close(c
->u
.x11
.s
);
3368 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3369 logevent("Forwarded port closed");
3370 assert(c
->u
.pfd
.s
!= NULL
);
3371 pfd_close(c
->u
.pfd
.s
);
3375 c
->closes
|= (closetype
<< 2); /* seen this message */
3376 if (!(c
->closes
& closetype
)) {
3377 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
,
3379 c
->closes
|= closetype
; /* sent it too */
3382 if (c
->closes
== 15) {
3383 del234(ssh_channels
, c
);
3387 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3388 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3389 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3392 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3393 /* Data sent down one of our channels. */
3394 int i
= GET_32BIT(pktin
.body
);
3395 int len
= GET_32BIT(pktin
.body
+ 4);
3396 unsigned char *p
= pktin
.body
+ 8;
3397 struct ssh_channel
*c
;
3398 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3403 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3406 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3409 /* Data for an agent message. Buffer it. */
3411 if (c
->u
.a
.lensofar
< 4) {
3412 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3413 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3417 c
->u
.a
.lensofar
+= l
;
3419 if (c
->u
.a
.lensofar
== 4) {
3421 4 + GET_32BIT(c
->u
.a
.msglen
);
3422 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3423 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3425 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3427 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3429 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3433 c
->u
.a
.lensofar
+= l
;
3435 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3436 void *reply
, *sentreply
;
3438 agent_query(c
->u
.a
.message
,
3439 c
->u
.a
.totallen
, &reply
,
3444 /* Fake SSH_AGENT_FAILURE. */
3445 sentreply
= "\0\0\0\1\5";
3448 send_packet(SSH1_MSG_CHANNEL_DATA
,
3449 PKT_INT
, c
->remoteid
,
3451 PKT_DATA
, sentreply
, replylen
,
3455 sfree(c
->u
.a
.message
);
3456 c
->u
.a
.lensofar
= 0;
3459 bufsize
= 0; /* agent channels never back up */
3462 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3463 c
->v
.v1
.throttling
= 1;
3467 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
3468 /* may be from EXEC_SHELL on some servers */
3469 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3470 /* may be from EXEC_SHELL on some servers
3471 * if no pty is available or in other odd cases. Ignore */
3472 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3474 ssh_exitcode
= GET_32BIT(pktin
.body
);
3475 sprintf(buf
, "Server sent command exit status %d",
3478 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3480 * In case `helpful' firewalls or proxies tack
3481 * extra human-readable text on the end of the
3482 * session which we might mistake for another
3483 * encrypted packet, we close the session once
3484 * we've sent EXIT_CONFIRMATION.
3486 ssh_state
= SSH_STATE_CLOSED
;
3489 bombout(("Strange packet received: type %d", pktin
.type
));
3494 int len
= min(inlen
, 512);
3495 send_packet(SSH1_CMSG_STDIN_DATA
,
3496 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3507 * Utility routine for decoding comma-separated strings in KEXINIT.
3509 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3511 int needlen
= strlen(needle
);
3514 * Is it at the start of the string?
3516 if (haylen
>= needlen
&& /* haystack is long enough */
3517 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3518 (haylen
== needlen
|| haystack
[needlen
] == ',')
3519 /* either , or EOS follows */
3523 * If not, search for the next comma and resume after that.
3524 * If no comma found, terminate.
3526 while (haylen
> 0 && *haystack
!= ',')
3527 haylen
--, haystack
++;
3530 haylen
--, haystack
++; /* skip over comma itself */
3535 * SSH2 key creation method.
3537 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
,
3541 /* First 20 bytes. */
3543 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3545 SHA_Bytes(&s
, H
, 20);
3546 SHA_Bytes(&s
, &chr
, 1);
3547 SHA_Bytes(&s
, sessid
, 20);
3548 SHA_Final(&s
, keyspace
);
3549 /* Next 20 bytes. */
3551 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3553 SHA_Bytes(&s
, H
, 20);
3554 SHA_Bytes(&s
, keyspace
, 20);
3555 SHA_Final(&s
, keyspace
+ 20);
3559 * Handle the SSH2 transport layer.
3561 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
3563 static int i
, j
, len
, nbits
, pbits
, warn
;
3565 static Bignum p
, g
, e
, f
, K
;
3566 static int kex_init_value
, kex_reply_value
;
3567 static const struct ssh_mac
**maclist
;
3569 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
3570 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
3571 static const struct ssh_mac
*csmac_tobe
= NULL
;
3572 static const struct ssh_mac
*scmac_tobe
= NULL
;
3573 static const struct ssh_compress
*cscomp_tobe
= NULL
;
3574 static const struct ssh_compress
*sccomp_tobe
= NULL
;
3575 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3576 static int hostkeylen
, siglen
;
3577 static void *hkey
; /* actual host key */
3578 static unsigned char exchange_hash
[20];
3579 static unsigned char keyspace
[40];
3580 static int n_preferred_ciphers
;
3581 static const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3582 static const struct ssh_compress
*preferred_comp
;
3583 static int cipherstr_started
;
3584 static int first_kex
;
3591 * Set up the preferred ciphers. (NULL => warn below here)
3593 n_preferred_ciphers
= 0;
3594 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3595 switch (cfg
.ssh_cipherlist
[i
]) {
3596 case CIPHER_BLOWFISH
:
3597 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_blowfish
;
3598 n_preferred_ciphers
++;
3601 if (cfg
.ssh2_des_cbc
) {
3602 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_des
;
3603 n_preferred_ciphers
++;
3607 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_3des
;
3608 n_preferred_ciphers
++;
3611 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_aes
;
3612 n_preferred_ciphers
++;
3615 /* Flag for later. Don't bother if it's the last in
3617 if (i
< CIPHER_MAX
- 1) {
3618 preferred_ciphers
[n_preferred_ciphers
] = NULL
;
3619 n_preferred_ciphers
++;
3626 * Set up preferred compression.
3628 if (cfg
.compression
)
3629 preferred_comp
= &ssh_zlib
;
3631 preferred_comp
= &ssh_comp_none
;
3634 * Be prepared to work around the buggy MAC problem.
3636 if (cfg
.buggymac
|| (ssh_remote_bugs
& BUG_SSH2_HMAC
))
3637 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
3639 maclist
= macs
, nmacs
= lenof(macs
);
3643 * Construct and send our key exchange packet.
3645 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
3646 for (i
= 0; i
< 16; i
++)
3647 ssh2_pkt_addbyte((unsigned char) random_byte());
3648 /* List key exchange algorithms. */
3649 ssh2_pkt_addstring_start();
3650 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3651 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
3652 if (i
< lenof(kex_algs
) - 1)
3653 ssh2_pkt_addstring_str(",");
3655 /* List server host key algorithms. */
3656 ssh2_pkt_addstring_start();
3657 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3658 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
3659 if (i
< lenof(hostkey_algs
) - 1)
3660 ssh2_pkt_addstring_str(",");
3662 /* List client->server encryption algorithms. */
3663 ssh2_pkt_addstring_start();
3664 cipherstr_started
= 0;
3665 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3666 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3667 if (!c
) continue; /* warning flag */
3668 for (j
= 0; j
< c
->nciphers
; j
++) {
3669 if (cipherstr_started
)
3670 ssh2_pkt_addstring_str(",");
3671 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3672 cipherstr_started
= 1;
3675 /* List server->client encryption algorithms. */
3676 ssh2_pkt_addstring_start();
3677 cipherstr_started
= 0;
3678 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3679 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3680 if (!c
) continue; /* warning flag */
3681 for (j
= 0; j
< c
->nciphers
; j
++) {
3682 if (cipherstr_started
)
3683 ssh2_pkt_addstring_str(",");
3684 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3685 cipherstr_started
= 1;
3688 /* List client->server MAC algorithms. */
3689 ssh2_pkt_addstring_start();
3690 for (i
= 0; i
< nmacs
; i
++) {
3691 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3693 ssh2_pkt_addstring_str(",");
3695 /* List server->client MAC algorithms. */
3696 ssh2_pkt_addstring_start();
3697 for (i
= 0; i
< nmacs
; i
++) {
3698 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3700 ssh2_pkt_addstring_str(",");
3702 /* List client->server compression algorithms. */
3703 ssh2_pkt_addstring_start();
3704 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3705 const struct ssh_compress
*c
=
3706 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3707 ssh2_pkt_addstring_str(c
->name
);
3708 if (i
< lenof(compressions
))
3709 ssh2_pkt_addstring_str(",");
3711 /* List server->client compression algorithms. */
3712 ssh2_pkt_addstring_start();
3713 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3714 const struct ssh_compress
*c
=
3715 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3716 ssh2_pkt_addstring_str(c
->name
);
3717 if (i
< lenof(compressions
))
3718 ssh2_pkt_addstring_str(",");
3720 /* List client->server languages. Empty list. */
3721 ssh2_pkt_addstring_start();
3722 /* List server->client languages. Empty list. */
3723 ssh2_pkt_addstring_start();
3724 /* First KEX packet does _not_ follow, because we're not that brave. */
3725 ssh2_pkt_addbool(FALSE
);
3727 ssh2_pkt_adduint32(0);
3729 exhash
= exhashbase
;
3730 sha_string(&exhash
, pktout
.data
+ 5, pktout
.length
- 5);
3736 sha_string(&exhash
, pktin
.data
+ 5, pktin
.length
- 5);
3739 * Now examine the other side's KEXINIT to see what we're up
3742 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
3743 bombout(("expected key exchange packet from server"));
3748 cscipher_tobe
= NULL
;
3749 sccipher_tobe
= NULL
;
3754 pktin
.savedpos
+= 16; /* skip garbage cookie */
3755 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
3756 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3757 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3762 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
3763 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3764 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3765 hostkey
= hostkey_algs
[i
];
3769 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
3771 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3772 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3776 for (j
= 0; j
< c
->nciphers
; j
++) {
3777 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3778 cscipher_tobe
= c
->list
[j
];
3783 if (cscipher_tobe
) {
3785 askcipher(cscipher_tobe
->name
, 1);
3789 if (!cscipher_tobe
) {
3790 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3794 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
3796 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3797 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3801 for (j
= 0; j
< c
->nciphers
; j
++) {
3802 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3803 sccipher_tobe
= c
->list
[j
];
3808 if (sccipher_tobe
) {
3810 askcipher(sccipher_tobe
->name
, 2);
3814 if (!sccipher_tobe
) {
3815 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3819 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
3820 for (i
= 0; i
< nmacs
; i
++) {
3821 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3822 csmac_tobe
= maclist
[i
];
3826 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
3827 for (i
= 0; i
< nmacs
; i
++) {
3828 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3829 scmac_tobe
= maclist
[i
];
3833 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
3834 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3835 const struct ssh_compress
*c
=
3836 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3837 if (in_commasep_string(c
->name
, str
, len
)) {
3842 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
3843 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3844 const struct ssh_compress
*c
=
3845 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3846 if (in_commasep_string(c
->name
, str
, len
)) {
3853 * Work out the number of bits of key we will need from the key
3854 * exchange. We start with the maximum key length of either
3860 csbits
= cscipher_tobe
->keylen
;
3861 scbits
= sccipher_tobe
->keylen
;
3862 nbits
= (csbits
> scbits ? csbits
: scbits
);
3864 /* The keys only have 160-bit entropy, since they're based on
3865 * a SHA-1 hash. So cap the key size at 160 bits. */
3870 * If we're doing Diffie-Hellman group exchange, start by
3871 * requesting a group.
3873 if (kex
== &ssh_diffiehellman_gex
) {
3874 logevent("Doing Diffie-Hellman group exchange");
3875 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3877 * Work out how big a DH group we will need to allow that
3880 pbits
= 512 << ((nbits
- 1) / 64);
3881 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
3882 ssh2_pkt_adduint32(pbits
);
3886 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3887 bombout(("expected key exchange group packet from server"));
3890 p
= ssh2_pkt_getmp();
3891 g
= ssh2_pkt_getmp();
3892 dh_setup_group(p
, g
);
3893 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3894 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3896 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3898 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3899 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3902 logevent("Doing Diffie-Hellman key exchange");
3904 * Now generate and send e for Diffie-Hellman.
3906 e
= dh_create_e(nbits
* 2);
3907 ssh2_pkt_init(kex_init_value
);
3912 if (pktin
.type
!= kex_reply_value
) {
3913 bombout(("expected key exchange reply packet from server"));
3916 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
3917 f
= ssh2_pkt_getmp();
3918 ssh2_pkt_getstring(&sigdata
, &siglen
);
3922 sha_string(&exhash
, hostkeydata
, hostkeylen
);
3923 if (kex
== &ssh_diffiehellman_gex
) {
3924 sha_uint32(&exhash
, pbits
);
3925 sha_mpint(&exhash
, p
);
3926 sha_mpint(&exhash
, g
);
3928 sha_mpint(&exhash
, e
);
3929 sha_mpint(&exhash
, f
);
3930 sha_mpint(&exhash
, K
);
3931 SHA_Final(&exhash
, exchange_hash
);
3936 debug(("Exchange hash is:\n"));
3937 dmemdump(exchange_hash
, 20);
3940 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
3942 !hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
3943 bombout(("Server's host key did not match the signature supplied"));
3948 * Authenticate remote host: verify host key. (We've already
3949 * checked the signature of the exchange hash.)
3951 keystr
= hostkey
->fmtkey(hkey
);
3952 fingerprint
= hostkey
->fingerprint(hkey
);
3953 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
3954 keystr
, fingerprint
);
3955 if (first_kex
) { /* don't bother logging this in rekeys */
3956 logevent("Host key fingerprint is:");
3957 logevent(fingerprint
);
3961 hostkey
->freekey(hkey
);
3964 * Send SSH2_MSG_NEWKEYS.
3966 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
3970 * Expect SSH2_MSG_NEWKEYS from server.
3973 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
3974 bombout(("expected new-keys packet from server"));
3979 * Create and initialise session keys.
3981 cscipher
= cscipher_tobe
;
3982 sccipher
= sccipher_tobe
;
3985 cscomp
= cscomp_tobe
;
3986 sccomp
= sccomp_tobe
;
3987 cscomp
->compress_init();
3988 sccomp
->decompress_init();
3990 * Set IVs after keys. Here we use the exchange hash from the
3991 * _first_ key exchange.
3994 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
3995 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
3996 cscipher
->setcskey(keyspace
);
3997 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
3998 sccipher
->setsckey(keyspace
);
3999 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
4000 cscipher
->setcsiv(keyspace
);
4001 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
4002 sccipher
->setsciv(keyspace
);
4003 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
4004 csmac
->setcskey(keyspace
);
4005 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
4006 scmac
->setsckey(keyspace
);
4009 * If this is the first key exchange phase, we must pass the
4010 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4011 * wants to see it but because it will need time to initialise
4012 * itself before it sees an actual packet. In subsequent key
4013 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4014 * it would only confuse the layer above.
4022 * Now we're encrypting. Begin returning 1 to the protocol main
4023 * function so that other things can run on top of the
4024 * transport. If we ever see a KEXINIT, we must go back to the
4027 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
4030 logevent("Server initiated key re-exchange");
4031 goto begin_key_exchange
;
4037 * Add data to an SSH2 channel output buffer.
4039 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4042 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4046 * Attempt to send data on an SSH2 channel.
4048 static int ssh2_try_send(struct ssh_channel
*c
)
4050 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4053 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4054 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4055 len
= c
->v
.v2
.remwindow
;
4056 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4057 len
= c
->v
.v2
.remmaxpkt
;
4058 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4059 ssh2_pkt_adduint32(c
->remoteid
);
4060 ssh2_pkt_addstring_start();
4061 ssh2_pkt_addstring_data(data
, len
);
4063 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4064 c
->v
.v2
.remwindow
-= len
;
4068 * After having sent as much data as we can, return the amount
4071 return bufchain_size(&c
->v
.v2
.outbuffer
);
4075 * Potentially enlarge the window on an SSH2 channel.
4077 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4080 * Never send WINDOW_ADJUST for a channel that the remote side
4081 * already thinks it's closed; there's no point, since it won't
4082 * be sending any more data anyway.
4087 if (newwin
> c
->v
.v2
.locwindow
) {
4088 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4089 ssh2_pkt_adduint32(c
->remoteid
);
4090 ssh2_pkt_adduint32(newwin
- c
->v
.v2
.locwindow
);
4092 c
->v
.v2
.locwindow
= newwin
;
4097 * Handle the SSH2 userauth and connection layers.
4099 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
4102 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4104 AUTH_KEYBOARD_INTERACTIVE
4108 AUTH_TYPE_PUBLICKEY
,
4109 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4110 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4112 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4113 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4115 static int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4116 static int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4117 static int kbd_inter_running
;
4118 static int we_are_in
;
4119 static int num_prompts
, curr_prompt
, echo
;
4120 static char username
[100];
4121 static int got_username
;
4122 static char pwprompt
[200];
4123 static char password
[100];
4124 static void *publickey_blob
;
4125 static int publickey_bloblen
;
4130 * Request userauth protocol, and await a response to it.
4132 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
4133 ssh2_pkt_addstring("ssh-userauth");
4135 crWaitUntilV(ispkt
);
4136 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4137 bombout(("Server refused user authentication protocol"));
4142 * We repeat this whole loop, including the username prompt,
4143 * until we manage a successful authentication. If the user
4144 * types the wrong _password_, they are sent back to the
4145 * beginning to try another username. (If they specify a
4146 * username in the config, they are never asked, even if they
4147 * do give a wrong password.)
4149 * I think this best serves the needs of
4151 * - the people who have no configuration, no keys, and just
4152 * want to try repeated (username,password) pairs until they
4153 * type both correctly
4155 * - people who have keys and configuration but occasionally
4156 * need to fall back to passwords
4158 * - people with a key held in Pageant, who might not have
4159 * logged in to a particular machine before; so they want to
4160 * type a username, and then _either_ their key will be
4161 * accepted, _or_ they will type a password. If they mistype
4162 * the username they will want to be able to get back and
4166 got_username
= FALSE
;
4171 if (got_username
&& !cfg
.change_username
) {
4173 * We got a username last time round this loop, and
4174 * with change_username turned off we don't try to get
4177 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4178 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4179 if (!ssh_get_line("login as: ",
4180 username
, sizeof(username
), FALSE
)) {
4182 * get_line failed to get a username.
4185 logevent("No username provided. Abandoning session.");
4186 ssh_state
= SSH_STATE_CLOSED
;
4191 c_write_str("login as: ");
4193 setup_userpass_input(username
, sizeof(username
), 1);
4195 crWaitUntilV(!ispkt
);
4196 ret
= process_userpass_input(in
, inlen
);
4201 c_write_str("\r\n");
4202 username
[strcspn(username
, "\n\r")] = '\0';
4205 strncpy(username
, cfg
.username
, sizeof(username
));
4206 username
[sizeof(username
)-1] = '\0';
4207 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4208 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
4212 got_username
= TRUE
;
4215 * Send an authentication request using method "none": (a)
4216 * just in case it succeeds, and (b) so that we know what
4217 * authentication methods we can usefully try next.
4219 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4221 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4222 ssh2_pkt_addstring(username
);
4223 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4224 ssh2_pkt_addstring("none"); /* method */
4226 type
= AUTH_TYPE_NONE
;
4230 tried_pubkey_config
= FALSE
;
4231 tried_agent
= FALSE
;
4232 tried_keyb_inter
= FALSE
;
4233 kbd_inter_running
= FALSE
;
4234 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4237 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4238 keytype
= key_type(cfg
.keyfile
);
4239 if (keytype
== SSH_KEYTYPE_SSH2
)
4240 publickey_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4241 &publickey_bloblen
);
4244 logeventf("Unable to use this key file (%s)",
4245 key_type_to_str(keytype
));
4246 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4247 cfg
.keyfile
, key_type_to_str(keytype
));
4248 c_write_str(msgbuf
);
4249 publickey_blob
= NULL
;
4252 publickey_blob
= NULL
;
4256 * Wait for the result of the last authentication request.
4259 crWaitUntilV(ispkt
);
4260 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4264 * Don't show the banner if we're operating in
4265 * non-verbose non-interactive mode. (It's probably
4266 * a script, which means nobody will read the
4267 * banner _anyway_, and moreover the printing of
4268 * the banner will screw up processing on the
4269 * output of (say) plink.)
4271 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4272 ssh2_pkt_getstring(&banner
, &size
);
4274 c_write_untrusted(banner
, size
);
4276 crWaitUntilV(ispkt
);
4278 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4279 logevent("Access granted");
4284 if (kbd_inter_running
&&
4285 pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4287 * This is either a further set-of-prompts packet
4288 * in keyboard-interactive authentication, or it's
4289 * the same one and we came back here with `gotit'
4290 * set. In the former case, we must reset the
4291 * curr_prompt variable.
4295 } else if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4296 bombout(("Strange packet received during authentication: type %d",
4304 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4305 * we can look at the string in it and know what we can
4306 * helpfully try next.
4308 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4311 ssh2_pkt_getstring(&methods
, &methlen
);
4312 kbd_inter_running
= FALSE
;
4313 if (!ssh2_pkt_getbool()) {
4315 * We have received an unequivocal Access
4316 * Denied. This can translate to a variety of
4319 * - if we'd just tried "none" authentication,
4320 * it's not worth printing anything at all
4322 * - if we'd just tried a public key _offer_,
4323 * the message should be "Server refused our
4324 * key" (or no message at all if the key
4325 * came from Pageant)
4327 * - if we'd just tried anything else, the
4328 * message really should be "Access denied".
4330 * Additionally, if we'd just tried password
4331 * authentication, we should break out of this
4332 * whole loop so as to go back to the username
4335 if (type
== AUTH_TYPE_NONE
) {
4337 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4338 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4339 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4340 c_write_str("Server refused our key\r\n");
4341 logevent("Server refused public key");
4342 } else if (type
== AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4343 /* server declined keyboard-interactive; ignore */
4345 c_write_str("Access denied\r\n");
4346 logevent("Access denied");
4347 if (type
== AUTH_TYPE_PASSWORD
) {
4353 c_write_str("Further authentication required\r\n");
4354 logevent("Further authentication required");
4358 in_commasep_string("publickey", methods
, methlen
);
4360 in_commasep_string("password", methods
, methlen
);
4361 can_keyb_inter
= cfg
.try_ki_auth
&&
4362 in_commasep_string("keyboard-interactive", methods
, methlen
);
4366 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4369 * Most password/passphrase prompts will be
4370 * non-echoing, so we set this to 0 by default.
4371 * Exception is that some keyboard-interactive prompts
4372 * can be echoing, in which case we'll set this to 1.
4376 if (!method
&& can_pubkey
&& agent_exists() && !tried_agent
) {
4378 * Attempt public-key authentication using Pageant.
4380 static unsigned char request
[5], *response
, *p
;
4381 static int responselen
;
4382 static int i
, nkeys
;
4383 static int authed
= FALSE
;
4386 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4387 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4391 logevent("Pageant is running. Requesting keys.");
4393 /* Request the keys held by the agent. */
4394 PUT_32BIT(request
, 1);
4395 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4396 agent_query(request
, 5, &r
, &responselen
);
4397 response
= (unsigned char *) r
;
4398 if (response
&& responselen
>= 5 &&
4399 response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4401 nkeys
= GET_32BIT(p
);
4405 sprintf(buf
, "Pageant has %d SSH2 keys", nkeys
);
4408 for (i
= 0; i
< nkeys
; i
++) {
4409 static char *pkblob
, *alg
, *commentp
;
4410 static int pklen
, alglen
, commentlen
;
4411 static int siglen
, retlen
, len
;
4412 static char *q
, *agentreq
, *ret
;
4417 sprintf(buf
, "Trying Pageant key #%d", i
);
4420 pklen
= GET_32BIT(p
);
4422 if (publickey_blob
&&
4423 pklen
== publickey_bloblen
&&
4424 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
4425 logevent("This key matches configured key file");
4426 tried_pubkey_config
= 1;
4430 alglen
= GET_32BIT(pkblob
);
4432 commentlen
= GET_32BIT(p
);
4436 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4437 ssh2_pkt_addstring(username
);
4438 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4439 ssh2_pkt_addstring("publickey"); /* method */
4440 ssh2_pkt_addbool(FALSE
); /* no signature included */
4441 ssh2_pkt_addstring_start();
4442 ssh2_pkt_addstring_data(alg
, alglen
);
4443 ssh2_pkt_addstring_start();
4444 ssh2_pkt_addstring_data(pkblob
, pklen
);
4447 crWaitUntilV(ispkt
);
4448 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4449 logevent("Key refused");
4453 if (flags
& FLAG_VERBOSE
) {
4455 ("Authenticating with public key \"");
4456 c_write(commentp
, commentlen
);
4457 c_write_str("\" from agent\r\n");
4461 * Server is willing to accept the key.
4462 * Construct a SIGN_REQUEST.
4464 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4465 ssh2_pkt_addstring(username
);
4466 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4467 ssh2_pkt_addstring("publickey"); /* method */
4468 ssh2_pkt_addbool(TRUE
);
4469 ssh2_pkt_addstring_start();
4470 ssh2_pkt_addstring_data(alg
, alglen
);
4471 ssh2_pkt_addstring_start();
4472 ssh2_pkt_addstring_data(pkblob
, pklen
);
4474 siglen
= pktout
.length
- 5 + 4 + 20;
4475 len
= 1; /* message type */
4476 len
+= 4 + pklen
; /* key blob */
4477 len
+= 4 + siglen
; /* data to sign */
4478 len
+= 4; /* flags */
4479 agentreq
= smalloc(4 + len
);
4480 PUT_32BIT(agentreq
, len
);
4482 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4483 PUT_32BIT(q
, pklen
);
4485 memcpy(q
, pkblob
, pklen
);
4487 PUT_32BIT(q
, siglen
);
4489 /* Now the data to be signed... */
4492 memcpy(q
, ssh2_session_id
, 20);
4494 memcpy(q
, pktout
.data
+ 5, pktout
.length
- 5);
4495 q
+= pktout
.length
- 5;
4496 /* And finally the (zero) flags word. */
4498 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
4502 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4503 logevent("Sending Pageant's response");
4504 ssh2_add_sigblob(pkblob
, pklen
,
4505 ret
+ 9, GET_32BIT(ret
+ 5));
4511 ("Pageant failed to answer challenge");
4521 if (!method
&& can_pubkey
&& publickey_blob
4522 && !tried_pubkey_config
) {
4523 unsigned char *pub_blob
;
4524 char *algorithm
, *comment
;
4527 tried_pubkey_config
= TRUE
;
4529 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4530 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4533 * Try the public key supplied in the configuration.
4535 * First, offer the public blob to see if the server is
4536 * willing to accept it.
4538 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4541 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4542 ssh2_pkt_addstring(username
);
4543 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4544 ssh2_pkt_addstring("publickey"); /* method */
4545 ssh2_pkt_addbool(FALSE
); /* no signature included */
4546 ssh2_pkt_addstring(algorithm
);
4547 ssh2_pkt_addstring_start();
4548 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
4550 logevent("Offered public key"); /* FIXME */
4552 crWaitUntilV(ispkt
);
4553 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4555 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4556 continue; /* key refused; give up on it */
4559 logevent("Offer of public key accepted");
4561 * Actually attempt a serious authentication using
4564 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4566 "Passphrase for key \"%.100s\": ",
4572 c_write_str("Authenticating with public key \"");
4573 c_write_str(comment
);
4574 c_write_str("\"\r\n");
4575 method
= AUTH_PUBLICKEY_FILE
;
4579 if (!method
&& can_keyb_inter
&& !tried_keyb_inter
) {
4580 method
= AUTH_KEYBOARD_INTERACTIVE
;
4581 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4582 tried_keyb_inter
= TRUE
;
4584 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4585 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4587 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4588 ssh2_pkt_addstring(username
);
4589 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4590 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4591 ssh2_pkt_addstring(""); /* lang */
4592 ssh2_pkt_addstring("");
4595 crWaitUntilV(ispkt
);
4596 if (pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4597 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4599 logevent("Keyboard-interactive authentication refused");
4600 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4604 kbd_inter_running
= TRUE
;
4608 if (kbd_inter_running
) {
4609 method
= AUTH_KEYBOARD_INTERACTIVE
;
4610 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4611 tried_keyb_inter
= TRUE
;
4613 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4614 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4616 if (curr_prompt
== 0) {
4618 * We've got a fresh USERAUTH_INFO_REQUEST.
4619 * Display header data, and start going through
4622 char *name
, *inst
, *lang
;
4623 int name_len
, inst_len
, lang_len
;
4625 ssh2_pkt_getstring(&name
, &name_len
);
4626 ssh2_pkt_getstring(&inst
, &inst_len
);
4627 ssh2_pkt_getstring(&lang
, &lang_len
);
4629 c_write_untrusted(name
, name_len
);
4630 c_write_str("\r\n");
4633 c_write_untrusted(inst
, inst_len
);
4634 c_write_str("\r\n");
4636 num_prompts
= ssh2_pkt_getuint32();
4640 * If there are prompts remaining in the packet,
4641 * display one and get a response.
4643 if (curr_prompt
< num_prompts
) {
4647 ssh2_pkt_getstring(&prompt
, &prompt_len
);
4648 if (prompt_len
> 0) {
4649 strncpy(pwprompt
, prompt
, sizeof(pwprompt
));
4650 pwprompt
[prompt_len
< sizeof(pwprompt
) ?
4651 prompt_len
: sizeof(pwprompt
)-1] = '\0';
4654 "<server failed to send prompt>: ");
4656 echo
= ssh2_pkt_getbool();
4662 if (!method
&& can_passwd
) {
4663 method
= AUTH_PASSWORD
;
4664 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4665 ssh_pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4666 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
,
4673 if (!ssh_get_line(pwprompt
, password
,
4674 sizeof(password
), TRUE
)) {
4676 * get_line failed to get a password (for
4677 * example because one was supplied on the
4678 * command line which has already failed to
4681 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4682 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4684 ("No more passwords available to try");
4685 ssh2_pkt_addstring("en"); /* language tag */
4687 logevent("Unable to authenticate");
4688 connection_fatal("Unable to authenticate");
4689 ssh_state
= SSH_STATE_CLOSED
;
4694 c_write_untrusted(pwprompt
, strlen(pwprompt
));
4697 setup_userpass_input(password
, sizeof(password
), echo
);
4699 crWaitUntilV(!ispkt
);
4700 ret
= process_userpass_input(in
, inlen
);
4704 c_write_str("\r\n");
4708 if (method
== AUTH_PUBLICKEY_FILE
) {
4710 * We have our passphrase. Now try the actual authentication.
4712 struct ssh2_userkey
*key
;
4714 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
4715 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4716 if (key
== SSH2_WRONG_PASSPHRASE
) {
4717 c_write_str("Wrong passphrase\r\n");
4718 tried_pubkey_config
= FALSE
;
4720 c_write_str("Unable to load private key\r\n");
4721 tried_pubkey_config
= TRUE
;
4723 /* Send a spurious AUTH_NONE to return to the top. */
4724 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4725 ssh2_pkt_addstring(username
);
4726 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4727 ssh2_pkt_addstring("none"); /* method */
4729 type
= AUTH_TYPE_NONE
;
4731 unsigned char *pkblob
, *sigblob
, *sigdata
;
4732 int pkblob_len
, sigblob_len
, sigdata_len
;
4735 * We have loaded the private key and the server
4736 * has announced that it's willing to accept it.
4737 * Hallelujah. Generate a signature and send it.
4739 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4740 ssh2_pkt_addstring(username
);
4741 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4742 ssh2_pkt_addstring("publickey"); /* method */
4743 ssh2_pkt_addbool(TRUE
);
4744 ssh2_pkt_addstring(key
->alg
->name
);
4745 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4746 ssh2_pkt_addstring_start();
4747 ssh2_pkt_addstring_data(pkblob
, pkblob_len
);
4750 * The data to be signed is:
4754 * followed by everything so far placed in the
4757 sigdata_len
= pktout
.length
- 5 + 4 + 20;
4758 sigdata
= smalloc(sigdata_len
);
4759 PUT_32BIT(sigdata
, 20);
4760 memcpy(sigdata
+ 4, ssh2_session_id
, 20);
4761 memcpy(sigdata
+ 24, pktout
.data
+ 5,
4763 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4764 sigdata_len
, &sigblob_len
);
4765 ssh2_add_sigblob(pkblob
, pkblob_len
,
4766 sigblob
, sigblob_len
);
4772 type
= AUTH_TYPE_PUBLICKEY
;
4774 } else if (method
== AUTH_PASSWORD
) {
4776 * We send the password packet lumped tightly together with
4777 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4778 * string long enough to make the total length of the two
4779 * packets constant. This should ensure that a passive
4780 * listener doing traffic analyis can't work out the length
4783 * For this to work, we need an assumption about the
4784 * maximum length of the password packet. I think 256 is
4785 * pretty conservative. Anyone using a password longer than
4786 * that probably doesn't have much to worry about from
4787 * people who find out how long their password is!
4789 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4790 ssh2_pkt_addstring(username
);
4791 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4792 ssh2_pkt_addstring("password");
4793 ssh2_pkt_addbool(FALSE
);
4794 ssh2_pkt_addstring(password
);
4797 * We'll include a string that's an exact multiple of the
4798 * cipher block size. If the cipher is NULL for some
4799 * reason, we don't do this trick at all because we gain
4805 stringlen
= (256 - deferred_len
);
4806 stringlen
+= cscipher
->blksize
- 1;
4807 stringlen
-= (stringlen
% cscipher
->blksize
);
4810 * Temporarily disable actual compression,
4811 * so we can guarantee to get this string
4812 * exactly the length we want it. The
4813 * compression-disabling routine should
4814 * return an integer indicating how many
4815 * bytes we should adjust our string length
4818 stringlen
-= cscomp
->disable_compression();
4820 ssh2_pkt_init(SSH2_MSG_IGNORE
);
4821 ssh2_pkt_addstring_start();
4822 for (i
= 0; i
< stringlen
; i
++) {
4823 char c
= (char) random_byte();
4824 ssh2_pkt_addstring_data(&c
, 1);
4828 ssh_pkt_defersend();
4829 logevent("Sent password");
4830 type
= AUTH_TYPE_PASSWORD
;
4831 } else if (method
== AUTH_KEYBOARD_INTERACTIVE
) {
4832 if (curr_prompt
== 0) {
4833 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4834 ssh2_pkt_adduint32(num_prompts
);
4836 if (need_pw
) { /* only add pw if we just got one! */
4837 ssh2_pkt_addstring(password
);
4838 memset(password
, 0, sizeof(password
));
4841 if (curr_prompt
>= num_prompts
) {
4845 * If there are prompts remaining, we set
4846 * `gotit' so that we won't attempt to get
4847 * another packet. Then we go back round the
4848 * loop and will end up retrieving another
4849 * prompt out of the existing packet. Funky or
4854 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4857 ("No supported authentication methods left to try!\r\n");
4859 ("No supported authentications offered. Disconnecting");
4860 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4861 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4863 ("No supported authentication methods available");
4864 ssh2_pkt_addstring("en"); /* language tag */
4866 ssh_state
= SSH_STATE_CLOSED
;
4870 } while (!we_are_in
);
4873 * Now we're authenticated for the connection protocol. The
4874 * connection protocol will automatically have started at this
4875 * point; there's no need to send SERVICE_REQUEST.
4879 * So now create a channel with a session in it.
4881 ssh_channels
= newtree234(ssh_channelcmp
);
4882 mainchan
= smalloc(sizeof(struct ssh_channel
));
4883 mainchan
->localid
= alloc_channel_id();
4884 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
4885 ssh2_pkt_addstring("session");
4886 ssh2_pkt_adduint32(mainchan
->localid
);
4887 mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
4888 ssh2_pkt_adduint32(mainchan
->v
.v2
.locwindow
); /* our window size */
4889 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
4891 crWaitUntilV(ispkt
);
4892 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
4893 bombout(("Server refused to open a session"));
4895 /* FIXME: error data comes back in FAILURE packet */
4897 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
4898 bombout(("Server's channel confirmation cited wrong channel"));
4901 mainchan
->remoteid
= ssh2_pkt_getuint32();
4902 mainchan
->type
= CHAN_MAINSESSION
;
4903 mainchan
->closes
= 0;
4904 mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
4905 mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
4906 bufchain_init(&mainchan
->v
.v2
.outbuffer
);
4907 add234(ssh_channels
, mainchan
);
4908 logevent("Opened channel for session");
4911 * Potentially enable X11 forwarding.
4913 if (cfg
.x11_forward
) {
4914 char proto
[20], data
[64];
4915 logevent("Requesting X11 forwarding");
4916 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
4917 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
4918 ssh2_pkt_adduint32(mainchan
->remoteid
);
4919 ssh2_pkt_addstring("x11-req");
4920 ssh2_pkt_addbool(1); /* want reply */
4921 ssh2_pkt_addbool(0); /* many connections */
4922 ssh2_pkt_addstring(proto
);
4923 ssh2_pkt_addstring(data
);
4924 ssh2_pkt_adduint32(0); /* screen number */
4928 crWaitUntilV(ispkt
);
4929 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
4930 unsigned i
= ssh2_pkt_getuint32();
4931 struct ssh_channel
*c
;
4932 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
4934 continue; /* nonexistent channel */
4935 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
4937 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4939 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
4940 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
4941 bombout(("Unexpected response to X11 forwarding request:"
4942 " packet type %d", pktin
.type
));
4945 logevent("X11 forwarding refused");
4947 logevent("X11 forwarding enabled");
4948 ssh_X11_fwd_enabled
= TRUE
;
4953 * Enable port forwardings.
4956 static char *e
; /* preserve across crReturn */
4959 int sport
,dport
,sserv
,dserv
;
4960 char sports
[256], dports
[256], host
[256];
4964 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4965 /* Add port forwardings. */
4970 while (*e
&& *e
!= '\t')
4976 while (*e
&& *e
!= ':')
4986 dport
= atoi(dports
);
4990 se
= getservbyname(dports
, NULL
);
4992 dport
= ntohs(se
->s_port
);
4995 "Service lookup failed for destination port \"%s\"",
5000 sport
= atoi(sports
);
5004 se
= getservbyname(sports
, NULL
);
5006 sport
= ntohs(se
->s_port
);
5009 "Service lookup failed for source port \"%s\"",
5014 if (sport
&& dport
) {
5016 pfd_addforward(host
, dport
, sport
);
5017 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
5018 " %s:%.*s%.*s%d%.*s",
5019 sserv ?
strlen(sports
) : 0, sports
,
5020 sserv
, "(", sport
, sserv
, ")",
5022 dserv ?
strlen(dports
) : 0, dports
,
5023 dserv
, "(", dport
, dserv
, ")");
5026 struct ssh_rportfwd
*pf
;
5027 pf
= smalloc(sizeof(*pf
));
5028 strcpy(pf
->dhost
, host
);
5031 if (add234(ssh_rportfwds
, pf
) != pf
) {
5033 "Duplicate remote port forwarding to %s:%d",
5038 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
5039 " forward to %s:%.*s%.*s%d%.*s",
5040 sserv ?
strlen(sports
) : 0, sports
,
5041 sserv
, "(", sport
, sserv
, ")",
5043 dserv ?
strlen(dports
) : 0, dports
,
5044 dserv
, "(", dport
, dserv
, ")");
5046 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
5047 ssh2_pkt_addstring("tcpip-forward");
5048 ssh2_pkt_addbool(1);/* want reply */
5049 if (cfg
.rport_acceptall
)
5050 ssh2_pkt_addstring("0.0.0.0");
5052 ssh2_pkt_addstring("127.0.0.1");
5053 ssh2_pkt_adduint32(sport
);
5057 crWaitUntilV(ispkt
);
5058 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5059 unsigned i
= ssh2_pkt_getuint32();
5060 struct ssh_channel
*c
;
5061 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5063 continue;/* nonexistent channel */
5064 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5066 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5068 if (pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5069 if (pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5070 bombout(("Unexpected response to port "
5071 "forwarding request: packet type %d",
5075 logevent("Server refused this port forwarding");
5077 logevent("Remote port forwarding enabled");
5086 * Potentially enable agent forwarding.
5088 if (cfg
.agentfwd
&& agent_exists()) {
5089 logevent("Requesting OpenSSH-style agent forwarding");
5090 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5091 ssh2_pkt_adduint32(mainchan
->remoteid
);
5092 ssh2_pkt_addstring("auth-agent-req@openssh.com");
5093 ssh2_pkt_addbool(1); /* want reply */
5097 crWaitUntilV(ispkt
);
5098 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5099 unsigned i
= ssh2_pkt_getuint32();
5100 struct ssh_channel
*c
;
5101 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5103 continue; /* nonexistent channel */
5104 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5106 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5108 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5109 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5110 bombout(("Unexpected response to agent forwarding request:"
5111 " packet type %d", pktin
.type
));
5114 logevent("Agent forwarding refused");
5116 logevent("Agent forwarding enabled");
5117 ssh_agentfwd_enabled
= TRUE
;
5122 * Now allocate a pty for the session.
5125 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5126 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5127 ssh2_pkt_addstring("pty-req");
5128 ssh2_pkt_addbool(1); /* want reply */
5129 ssh2_pkt_addstring(cfg
.termtype
);
5130 ssh2_pkt_adduint32(cols
);
5131 ssh2_pkt_adduint32(rows
);
5132 ssh2_pkt_adduint32(0); /* pixel width */
5133 ssh2_pkt_adduint32(0); /* pixel height */
5134 ssh2_pkt_addstring_start();
5135 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
5137 ssh_state
= SSH_STATE_INTERMED
;
5140 crWaitUntilV(ispkt
);
5141 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5142 unsigned i
= ssh2_pkt_getuint32();
5143 struct ssh_channel
*c
;
5144 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5146 continue; /* nonexistent channel */
5147 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5149 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5151 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5152 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5153 bombout(("Unexpected response to pty request:"
5154 " packet type %d", pktin
.type
));
5157 c_write_str("Server refused to allocate pty\r\n");
5158 ssh_editing
= ssh_echoing
= 1;
5160 logevent("Allocated pty");
5163 ssh_editing
= ssh_echoing
= 1;
5167 * Start a shell or a remote command. We may have to attempt
5168 * this twice if the config data has provided a second choice
5175 if (ssh_fallback_cmd
) {
5176 subsys
= cfg
.ssh_subsys2
;
5177 cmd
= cfg
.remote_cmd_ptr2
;
5179 subsys
= cfg
.ssh_subsys
;
5180 cmd
= cfg
.remote_cmd_ptr
;
5183 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5184 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5186 ssh2_pkt_addstring("subsystem");
5187 ssh2_pkt_addbool(1); /* want reply */
5188 ssh2_pkt_addstring(cmd
);
5190 ssh2_pkt_addstring("exec");
5191 ssh2_pkt_addbool(1); /* want reply */
5192 ssh2_pkt_addstring(cmd
);
5194 ssh2_pkt_addstring("shell");
5195 ssh2_pkt_addbool(1); /* want reply */
5199 crWaitUntilV(ispkt
);
5200 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5201 unsigned i
= ssh2_pkt_getuint32();
5202 struct ssh_channel
*c
;
5203 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5205 continue; /* nonexistent channel */
5206 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5208 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5209 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5210 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5211 bombout(("Unexpected response to shell/command request:"
5212 " packet type %d", pktin
.type
));
5216 * We failed to start the command. If this is the
5217 * fallback command, we really are finished; if it's
5218 * not, and if the fallback command exists, try falling
5219 * back to it before complaining.
5221 if (!ssh_fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5222 logevent("Primary command failed; attempting fallback");
5223 ssh_fallback_cmd
= TRUE
;
5226 bombout(("Server refused to start a shell/command"));
5229 logevent("Started a shell/command");
5234 ssh_state
= SSH_STATE_SESSION
;
5238 ssh_special(TS_EOF
);
5243 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
5246 static int try_send
;
5250 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5251 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5254 unsigned i
= ssh2_pkt_getuint32();
5255 struct ssh_channel
*c
;
5256 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5258 continue; /* nonexistent channel */
5259 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5260 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
5261 continue; /* extended but not stderr */
5262 ssh2_pkt_getstring(&data
, &length
);
5265 c
->v
.v2
.locwindow
-= length
;
5267 case CHAN_MAINSESSION
:
5269 from_backend(pktin
.type
==
5270 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5274 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5277 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5280 while (length
> 0) {
5281 if (c
->u
.a
.lensofar
< 4) {
5282 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5283 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5287 c
->u
.a
.lensofar
+= l
;
5289 if (c
->u
.a
.lensofar
== 4) {
5291 4 + GET_32BIT(c
->u
.a
.msglen
);
5292 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5293 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5295 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5297 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5299 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5303 c
->u
.a
.lensofar
+= l
;
5305 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5306 void *reply
, *sentreply
;
5308 agent_query(c
->u
.a
.message
,
5309 c
->u
.a
.totallen
, &reply
,
5314 /* Fake SSH_AGENT_FAILURE. */
5315 sentreply
= "\0\0\0\1\5";
5318 ssh2_add_channel_data(c
, sentreply
,
5323 sfree(c
->u
.a
.message
);
5324 c
->u
.a
.lensofar
= 0;
5331 * If we are not buffering too much data,
5332 * enlarge the window again at the remote side.
5334 if (bufsize
< OUR_V2_WINSIZE
)
5335 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5337 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
5338 ssh_state
= SSH_STATE_CLOSED
;
5339 logevent("Received disconnect message");
5341 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5342 unsigned i
= ssh2_pkt_getuint32();
5343 struct ssh_channel
*c
;
5345 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5347 continue; /* nonexistent channel */
5349 if (c
->type
== CHAN_X11
) {
5351 * Remote EOF on an X11 channel means we should
5352 * wrap up and close the channel ourselves.
5354 x11_close(c
->u
.x11
.s
);
5356 } else if (c
->type
== CHAN_AGENT
) {
5358 } else if (c
->type
== CHAN_SOCKDATA
) {
5359 pfd_close(c
->u
.pfd
.s
);
5362 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5363 unsigned i
= ssh2_pkt_getuint32();
5364 struct ssh_channel
*c
;
5366 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5367 if (!c
|| ((int)c
->remoteid
) == -1) {
5368 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5369 c ?
"half-open" : "nonexistent", i
));
5371 /* Do pre-close processing on the channel. */
5373 case CHAN_MAINSESSION
:
5374 break; /* nothing to see here, move along */
5376 if (c
->u
.x11
.s
!= NULL
)
5377 x11_close(c
->u
.x11
.s
);
5384 if (c
->u
.pfd
.s
!= NULL
)
5385 pfd_close(c
->u
.pfd
.s
);
5389 if (c
->closes
== 0) {
5390 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5391 ssh2_pkt_adduint32(c
->remoteid
);
5394 del234(ssh_channels
, c
);
5395 bufchain_clear(&c
->v
.v2
.outbuffer
);
5399 * See if that was the last channel left open.
5401 if (count234(ssh_channels
) == 0) {
5404 * We used to send SSH_MSG_DISCONNECT here,
5405 * because I'd believed that _every_ conforming
5406 * SSH2 connection had to end with a disconnect
5407 * being sent by at least one side; apparently
5408 * I was wrong and it's perfectly OK to
5409 * unceremoniously slam the connection shut
5410 * when you're done, and indeed OpenSSH feels
5411 * this is more polite than sending a
5412 * DISCONNECT. So now we don't.
5414 logevent("All channels closed. Disconnecting");
5415 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5416 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5417 ssh2_pkt_addstring("All open channels closed");
5418 ssh2_pkt_addstring("en"); /* language tag */
5421 ssh_state
= SSH_STATE_CLOSED
;
5424 continue; /* remote sends close; ignore (FIXME) */
5425 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5426 unsigned i
= ssh2_pkt_getuint32();
5427 struct ssh_channel
*c
;
5428 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5430 continue; /* nonexistent channel */
5431 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5433 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5434 unsigned i
= ssh2_pkt_getuint32();
5435 struct ssh_channel
*c
;
5436 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5438 continue; /* nonexistent channel */
5439 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5440 continue; /* dunno why they're confirming this */
5441 c
->remoteid
= ssh2_pkt_getuint32();
5442 c
->type
= CHAN_SOCKDATA
;
5443 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
5444 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
5446 pfd_confirm(c
->u
.pfd
.s
);
5449 * We have a pending close on this channel,
5450 * which we decided on before the server acked
5451 * the channel open. So now we know the
5452 * remoteid, we can close it again.
5454 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5455 ssh2_pkt_adduint32(c
->remoteid
);
5458 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5459 unsigned i
= ssh2_pkt_getuint32();
5460 struct ssh_channel
*c
;
5461 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5463 continue; /* nonexistent channel */
5464 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5465 continue; /* dunno why they're failing this */
5467 logevent("Forwarded connection refused by server");
5469 pfd_close(c
->u
.pfd
.s
);
5471 del234(ssh_channels
, c
);
5473 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5476 int typelen
, want_reply
;
5477 struct ssh_channel
*c
;
5479 localid
= ssh2_pkt_getuint32();
5480 ssh2_pkt_getstring(&type
, &typelen
);
5481 want_reply
= ssh2_pkt_getbool();
5484 * First, check that the channel exists. Otherwise,
5485 * we can instantly disconnect with a rude message.
5487 c
= find234(ssh_channels
, &localid
, ssh_channelfind
);
5490 sprintf(buf
, "Received channel request for nonexistent"
5491 " channel %d", localid
);
5493 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5494 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5495 ssh2_pkt_addstring(buf
);
5496 ssh2_pkt_addstring("en"); /* language tag */
5498 connection_fatal("%s", buf
);
5499 ssh_state
= SSH_STATE_CLOSED
;
5504 * Having got the channel number, we now look at
5505 * the request type string to see if it's something
5508 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5510 /* We recognise "exit-status" on the primary channel. */
5512 ssh_exitcode
= ssh2_pkt_getuint32();
5513 sprintf(buf
, "Server sent command exit status %d",
5517 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS
);
5518 ssh2_pkt_adduint32(c
->remoteid
);
5523 * This is a channel request we don't know
5524 * about, so we now either ignore the request
5525 * or respond with CHANNEL_FAILURE, depending
5529 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE
);
5530 ssh2_pkt_adduint32(c
->remoteid
);
5534 } else if (pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5536 int typelen
, want_reply
;
5538 ssh2_pkt_getstring(&type
, &typelen
);
5539 want_reply
= ssh2_pkt_getbool();
5542 * We currently don't support any global requests
5543 * at all, so we either ignore the request or
5544 * respond with REQUEST_FAILURE, depending on
5548 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5551 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5555 struct ssh_channel
*c
;
5556 unsigned remid
, winsize
, pktsize
;
5557 ssh2_pkt_getstring(&type
, &typelen
);
5558 c
= smalloc(sizeof(struct ssh_channel
));
5560 remid
= ssh2_pkt_getuint32();
5561 winsize
= ssh2_pkt_getuint32();
5562 pktsize
= ssh2_pkt_getuint32();
5564 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5565 if (!ssh_X11_fwd_enabled
)
5566 error
= "X11 forwarding is not enabled";
5567 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5569 error
= "Unable to open an X11 connection";
5573 } else if (typelen
== 15 &&
5574 !memcmp(type
, "forwarded-tcpip", 15)) {
5575 struct ssh_rportfwd pf
, *realpf
;
5578 ssh2_pkt_getstring(&dummy
, &dummylen
);/* skip address */
5579 pf
.sport
= ssh2_pkt_getuint32();
5580 realpf
= find234(ssh_rportfwds
, &pf
, NULL
);
5581 if (realpf
== NULL
) {
5582 error
= "Remote port is not recognised";
5584 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5587 sprintf(buf
, "Received remote port open request for %s:%d",
5588 realpf
->dhost
, realpf
->dport
);
5591 sprintf(buf
, "Port open failed: %s", e
);
5593 error
= "Port open failed";
5595 logevent("Forwarded port opened successfully");
5596 c
->type
= CHAN_SOCKDATA
;
5599 } else if (typelen
== 22 &&
5600 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5601 if (!ssh_agentfwd_enabled
)
5602 error
= "Agent forwarding is not enabled";
5604 c
->type
= CHAN_AGENT
; /* identify channel type */
5605 c
->u
.a
.lensofar
= 0;
5608 error
= "Unsupported channel type requested";
5611 c
->remoteid
= remid
;
5613 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5614 ssh2_pkt_adduint32(c
->remoteid
);
5615 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
5616 ssh2_pkt_addstring(error
);
5617 ssh2_pkt_addstring("en"); /* language tag */
5621 c
->localid
= alloc_channel_id();
5623 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5624 c
->v
.v2
.remwindow
= winsize
;
5625 c
->v
.v2
.remmaxpkt
= pktsize
;
5626 bufchain_init(&c
->v
.v2
.outbuffer
);
5627 add234(ssh_channels
, c
);
5628 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5629 ssh2_pkt_adduint32(c
->remoteid
);
5630 ssh2_pkt_adduint32(c
->localid
);
5631 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);
5632 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5636 bombout(("Strange packet received: type %d", pktin
.type
));
5641 * We have spare data. Add it to the channel buffer.
5643 ssh2_add_channel_data(mainchan
, in
, inlen
);
5648 struct ssh_channel
*c
;
5650 * Try to send data on all channels if we can.
5652 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
5653 int bufsize
= ssh2_try_send(c
);
5656 case CHAN_MAINSESSION
:
5657 /* stdin need not receive an unthrottle
5658 * notification since it will be polled */
5661 x11_unthrottle(c
->u
.x11
.s
);
5664 /* agent sockets are request/response and need no
5665 * buffer management */
5668 pfd_unthrottle(c
->u
.pfd
.s
);
5680 * Handle the top-level SSH2 protocol.
5682 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
5684 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
5686 do_ssh2_authconn(in
, inlen
, ispkt
);
5690 * Called to set up the connection.
5692 * Returns an error message, or NULL on success.
5694 static char *ssh_init(char *host
, int port
, char **realhost
, int nodelay
)
5699 if (crypto_startup() == 0)
5700 return "Microsoft high encryption pack not installed!";
5706 ssh1_throttle_count
= 0;
5707 ssh_overall_bufsize
= 0;
5708 ssh_fallback_cmd
= 0;
5710 p
= connect_to_host(host
, port
, realhost
, nodelay
);
5718 * Called to send data down the Telnet connection.
5720 static int ssh_send(char *buf
, int len
)
5722 if (s
== NULL
|| ssh_protocol
== NULL
)
5725 ssh_protocol(buf
, len
, 0);
5727 return ssh_sendbuffer();
5731 * Called to query the current amount of buffered stdin data.
5733 static int ssh_sendbuffer(void)
5737 if (s
== NULL
|| ssh_protocol
== NULL
)
5741 * If the SSH socket itself has backed up, add the total backup
5742 * size on that to any individual buffer on the stdin channel.
5745 if (ssh_throttled_all
)
5746 override_value
= ssh_overall_bufsize
;
5748 if (ssh_version
== 1) {
5749 return override_value
;
5750 } else if (ssh_version
== 2) {
5751 if (!mainchan
|| mainchan
->closes
> 0)
5752 return override_value
;
5754 return override_value
+ bufchain_size(&mainchan
->v
.v2
.outbuffer
);
5761 * Called to set the size of the window from SSH's POV.
5763 static void ssh_size(void)
5765 switch (ssh_state
) {
5766 case SSH_STATE_BEFORE_SIZE
:
5767 case SSH_STATE_PREPACKET
:
5768 case SSH_STATE_CLOSED
:
5769 break; /* do nothing */
5770 case SSH_STATE_INTERMED
:
5771 size_needed
= TRUE
; /* buffer for later */
5773 case SSH_STATE_SESSION
:
5775 if (ssh_version
== 1) {
5776 send_packet(SSH1_CMSG_WINDOW_SIZE
,
5777 PKT_INT
, rows
, PKT_INT
, cols
,
5778 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5780 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5781 ssh2_pkt_adduint32(mainchan
->remoteid
);
5782 ssh2_pkt_addstring("window-change");
5783 ssh2_pkt_addbool(0);
5784 ssh2_pkt_adduint32(cols
);
5785 ssh2_pkt_adduint32(rows
);
5786 ssh2_pkt_adduint32(0);
5787 ssh2_pkt_adduint32(0);
5796 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5797 * can send an EOF and collect resulting output (e.g. `plink
5800 static void ssh_special(Telnet_Special code
)
5802 if (code
== TS_EOF
) {
5803 if (ssh_state
!= SSH_STATE_SESSION
) {
5805 * Buffer the EOF in case we are pre-SESSION, so we can
5806 * send it as soon as we reach SESSION.
5812 if (ssh_version
== 1) {
5813 send_packet(SSH1_CMSG_EOF
, PKT_END
);
5815 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
5816 ssh2_pkt_adduint32(mainchan
->remoteid
);
5819 logevent("Sent EOF message");
5820 } else if (code
== TS_PING
) {
5821 if (ssh_state
== SSH_STATE_CLOSED
5822 || ssh_state
== SSH_STATE_PREPACKET
) return;
5823 if (ssh_version
== 1) {
5824 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
5825 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
5827 ssh2_pkt_init(SSH2_MSG_IGNORE
);
5828 ssh2_pkt_addstring_start();
5836 void *new_sock_channel(Socket s
)
5838 struct ssh_channel
*c
;
5839 c
= smalloc(sizeof(struct ssh_channel
));
5842 c
->remoteid
= -1; /* to be set when open confirmed */
5843 c
->localid
= alloc_channel_id();
5845 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
5847 bufchain_init(&c
->v
.v2
.outbuffer
);
5848 add234(ssh_channels
, c
);
5854 * This is called when stdout/stderr (the entity to which
5855 * from_backend sends data) manages to clear some backlog.
5857 void ssh_unthrottle(int bufsize
)
5859 if (ssh_version
== 1) {
5860 if (ssh1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
5861 ssh1_stdout_throttling
= 0;
5865 if (mainchan
&& mainchan
->closes
== 0)
5866 ssh2_set_window(mainchan
, OUR_V2_WINSIZE
- bufsize
);
5870 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
5872 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
5875 sprintf(buf
, "Opening forwarded connection to %.512s:%d", hostname
, port
);
5878 if (ssh_version
== 1) {
5879 send_packet(SSH1_MSG_PORT_OPEN
,
5880 PKT_INT
, c
->localid
,
5883 //PKT_STR, <org:orgport>,
5886 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
5887 ssh2_pkt_addstring("direct-tcpip");
5888 ssh2_pkt_adduint32(c
->localid
);
5889 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5890 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);/* our window size */
5891 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5892 ssh2_pkt_addstring(hostname
);
5893 ssh2_pkt_adduint32(port
);
5895 * We make up values for the originator data; partly it's
5896 * too much hassle to keep track, and partly I'm not
5897 * convinced the server should be told details like that
5898 * about my local network configuration.
5900 ssh2_pkt_addstring("client-side-connection");
5901 ssh2_pkt_adduint32(0);
5907 static Socket
ssh_socket(void)
5912 static int ssh_sendok(void)
5917 static int ssh_ldisc(int option
)
5919 if (option
== LD_ECHO
)
5921 if (option
== LD_EDIT
)
5926 static int ssh_return_exitcode(void)
5928 return ssh_exitcode
;
5931 Backend ssh_backend
= {
5938 ssh_return_exitcode
,