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
;
431 struct ssh1_data_channel
{
434 struct ssh2_data_channel
{
436 unsigned remwindow
, remmaxpkt
;
441 struct ssh_agent_channel
{
442 unsigned char *message
;
443 unsigned char msglen
[4];
444 int lensofar
, totallen
;
446 struct ssh_x11_channel
{
449 struct ssh_pfd_channel
{
456 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
457 * 2 use this structure in different ways, reflecting SSH 2's
458 * altogether saner approach to port forwarding.
460 * In SSH 1, you arrange a remote forwarding by sending the server
461 * the remote port number, and the local destination host:port.
462 * When a connection comes in, the server sends you back that
463 * host:port pair, and you connect to it. This is a ready-made
464 * security hole if you're not on the ball: a malicious server
465 * could send you back _any_ host:port pair, so if you trustingly
466 * connect to the address it gives you then you've just opened the
467 * entire inside of your corporate network just by connecting
468 * through it to a dodgy SSH server. Hence, we must store a list of
469 * host:port pairs we _are_ trying to forward to, and reject a
470 * connection request from the server if it's not in the list.
472 * In SSH 2, each side of the connection minds its own business and
473 * doesn't send unnecessary information to the other. You arrange a
474 * remote forwarding by sending the server just the remote port
475 * number. When a connection comes in, the server tells you which
476 * of its ports was connected to; and _you_ have to remember what
477 * local host:port pair went with that port number.
479 * Hence: in SSH 1 this structure stores host:port pairs we intend
480 * to allow connections to, and is indexed by those host:port
481 * pairs. In SSH 2 it stores a mapping from source port to
482 * destination host:port pair, and is indexed by source port.
484 struct ssh_rportfwd
{
485 unsigned sport
, dport
;
498 static SHA_State exhash
, exhashbase
;
500 static Socket s
= NULL
;
502 static unsigned char session_key
[32];
503 static int ssh1_compressing
;
504 static int ssh1_remote_protoflags
;
505 static int ssh1_local_protoflags
;
506 static int ssh_agentfwd_enabled
;
507 static int ssh_X11_fwd_enabled
;
508 static int ssh_remote_bugs
;
509 static const struct ssh_cipher
*cipher
= NULL
;
510 static const struct ssh2_cipher
*cscipher
= NULL
;
511 static const struct ssh2_cipher
*sccipher
= NULL
;
512 static const struct ssh_mac
*csmac
= NULL
;
513 static const struct ssh_mac
*scmac
= NULL
;
514 static const struct ssh_compress
*cscomp
= NULL
;
515 static const struct ssh_compress
*sccomp
= NULL
;
516 static const struct ssh_kex
*kex
= NULL
;
517 static const struct ssh_signkey
*hostkey
= NULL
;
518 static unsigned char ssh2_session_id
[20];
520 static char *savedhost
;
521 static int savedport
;
522 static int ssh_send_ok
;
523 static int ssh_echoing
, ssh_editing
;
525 static tree234
*ssh_channels
; /* indexed by local id */
526 static struct ssh_channel
*mainchan
; /* primary session channel */
527 static int ssh_exitcode
= -1;
529 static tree234
*ssh_rportfwds
;
533 SSH_STATE_BEFORE_SIZE
,
537 } ssh_state
= SSH_STATE_PREPACKET
;
539 static int size_needed
= FALSE
, eof_needed
= FALSE
;
541 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
542 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
543 static unsigned char *deferred_send_data
= NULL
;
544 static int deferred_len
= 0, deferred_size
= 0;
547 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
548 * that fails. This variable is the means by which scp.c can reach
549 * into the SSH code and find out which one it got.
551 int ssh_fallback_cmd
= 0;
553 static int ssh_version
;
554 static int ssh1_throttle_count
;
555 static int ssh_overall_bufsize
;
556 static int ssh_throttled_all
;
557 static int ssh1_stdout_throttling
;
558 static void (*ssh_protocol
) (unsigned char *in
, int inlen
, int ispkt
);
559 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
560 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
561 static void ssh_size(void);
562 static void ssh_special(Telnet_Special
);
563 static int ssh2_try_send(struct ssh_channel
*c
);
564 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
566 static void ssh_throttle_all(int enable
, int bufsize
);
567 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
568 static int (*s_rdpkt
) (unsigned char **data
, int *datalen
);
569 static int ssh_sendbuffer(void);
571 static struct rdpkt1_state_tag
{
572 long len
, pad
, biglen
, to_read
;
573 unsigned long realcrc
, gotcrc
;
579 static struct rdpkt2_state_tag
{
580 long len
, pad
, payload
, packetlen
, maclen
;
583 unsigned long incoming_sequence
;
586 static int ssh_channelcmp(void *av
, void *bv
)
588 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
589 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
590 if (a
->localid
< b
->localid
)
592 if (a
->localid
> b
->localid
)
596 static int ssh_channelfind(void *av
, void *bv
)
598 unsigned *a
= (unsigned *) av
;
599 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
607 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
609 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
610 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
612 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
613 return i
< 0 ?
-1 : +1;
614 if (a
->dport
> b
->dport
)
616 if (a
->dport
< b
->dport
)
621 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
623 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
624 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
626 if (a
->sport
> b
->sport
)
628 if (a
->sport
< b
->sport
)
633 static int alloc_channel_id(void)
635 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
636 unsigned low
, high
, mid
;
638 struct ssh_channel
*c
;
641 * First-fit allocation of channel numbers: always pick the
642 * lowest unused one. To do this, binary-search using the
643 * counted B-tree to find the largest channel ID which is in a
644 * contiguous sequence from the beginning. (Precisely
645 * everything in that sequence must have ID equal to its tree
646 * index plus CHANNEL_NUMBER_OFFSET.)
648 tsize
= count234(ssh_channels
);
652 while (high
- low
> 1) {
653 mid
= (high
+ low
) / 2;
654 c
= index234(ssh_channels
, mid
);
655 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
656 low
= mid
; /* this one is fine */
658 high
= mid
; /* this one is past it */
661 * Now low points to either -1, or the tree index of the
662 * largest ID in the initial sequence.
665 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
666 assert(NULL
== find234(ssh_channels
, &i
, ssh_channelfind
));
668 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
671 static void c_write(char *buf
, int len
)
673 if ((flags
& FLAG_STDERR
)) {
675 for (i
= 0; i
< len
; i
++)
677 fputc(buf
[i
], stderr
);
680 from_backend(1, buf
, len
);
683 static void c_write_untrusted(char *buf
, int len
)
686 for (i
= 0; i
< len
; i
++) {
689 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
694 static void c_write_str(char *buf
)
696 c_write(buf
, strlen(buf
));
700 * Collect incoming data in the incoming packet buffer.
701 * Decipher and verify the packet when it is completely read.
702 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
703 * Update the *data and *datalen variables.
704 * Return the additional nr of bytes needed, or 0 when
705 * a complete packet is available.
707 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
709 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
718 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
719 while ((*datalen
) == 0)
721 st
->len
= (st
->len
<< 8) + **data
;
722 (*data
)++, (*datalen
)--;
725 st
->pad
= 8 - (st
->len
% 8);
726 st
->biglen
= st
->len
+ st
->pad
;
727 pktin
.length
= st
->len
- 5;
729 if (pktin
.maxlen
< st
->biglen
) {
730 pktin
.maxlen
= st
->biglen
;
731 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+ APIEXTRA
) :
732 srealloc(pktin
.data
, st
->biglen
+ APIEXTRA
));
734 fatalbox("Out of memory");
737 st
->to_read
= st
->biglen
;
739 while (st
->to_read
> 0) {
740 st
->chunk
= st
->to_read
;
741 while ((*datalen
) == 0)
742 crReturn(st
->to_read
);
743 if (st
->chunk
> (*datalen
))
744 st
->chunk
= (*datalen
);
745 memcpy(st
->p
, *data
, st
->chunk
);
747 *datalen
-= st
->chunk
;
749 st
->to_read
-= st
->chunk
;
752 if (cipher
&& detect_attack(pktin
.data
, st
->biglen
, NULL
)) {
753 bombout(("Network attack (CRC compensation) detected!"));
758 cipher
->decrypt(pktin
.data
, st
->biglen
);
760 st
->realcrc
= crc32(pktin
.data
, st
->biglen
- 4);
761 st
->gotcrc
= GET_32BIT(pktin
.data
+ st
->biglen
- 4);
762 if (st
->gotcrc
!= st
->realcrc
) {
763 bombout(("Incorrect CRC received on packet"));
767 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
769 if (ssh1_compressing
) {
770 unsigned char *decompblk
;
772 zlib_decompress_block(pktin
.body
- 1, pktin
.length
+ 1,
773 &decompblk
, &decomplen
);
775 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
776 pktin
.maxlen
= st
->pad
+ decomplen
;
777 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+ APIEXTRA
);
778 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
780 fatalbox("Out of memory");
783 memcpy(pktin
.body
- 1, decompblk
, decomplen
);
785 pktin
.length
= decomplen
- 1;
788 pktin
.type
= pktin
.body
[-1];
790 log_packet(PKT_INCOMING
, pktin
.type
, ssh1_pkt_type(pktin
.type
),
791 pktin
.body
, pktin
.length
);
793 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
794 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
795 pktin
.type
== SSH1_MSG_DEBUG
||
796 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
797 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
798 long stringlen
= GET_32BIT(pktin
.body
);
799 if (stringlen
+ 4 != pktin
.length
) {
800 bombout(("Received data packet with bogus string length"));
805 if (pktin
.type
== SSH1_MSG_DEBUG
) {
806 /* log debug message */
808 int stringlen
= GET_32BIT(pktin
.body
);
809 strcpy(buf
, "Remote debug message: ");
812 memcpy(buf
+ 8, pktin
.body
+ 4, stringlen
);
813 buf
[8 + stringlen
] = '\0';
816 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
821 if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
822 /* log reason code in disconnect message */
824 unsigned msglen
= GET_32BIT(pktin
.body
);
826 strcpy(buf
, "Remote sent disconnect: ");
827 nowlen
= strlen(buf
);
828 if (msglen
> sizeof(buf
) - nowlen
- 1)
829 msglen
= sizeof(buf
) - nowlen
- 1;
830 memcpy(buf
+ nowlen
, pktin
.body
+ 4, msglen
);
831 buf
[nowlen
+ msglen
] = '\0';
832 /* logevent(buf); (this is now done within the bombout macro) */
833 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
840 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
842 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
850 st
->cipherblk
= sccipher
->blksize
;
853 if (st
->cipherblk
< 8)
856 if (pktin
.maxlen
< st
->cipherblk
) {
857 pktin
.maxlen
= st
->cipherblk
;
860 NULL ?
smalloc(st
->cipherblk
+
861 APIEXTRA
) : srealloc(pktin
.data
,
865 fatalbox("Out of memory");
869 * Acquire and decrypt the first block of the packet. This will
870 * contain the length and padding details.
872 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
873 while ((*datalen
) == 0)
874 crReturn(st
->cipherblk
- st
->i
);
875 pktin
.data
[st
->i
] = *(*data
)++;
880 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
883 * Now get the length and padding figures.
885 st
->len
= GET_32BIT(pktin
.data
);
886 st
->pad
= pktin
.data
[4];
889 * _Completely_ silly lengths should be stomped on before they
890 * do us any more damage.
892 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
893 bombout(("Incoming packet was garbled on decryption"));
898 * This enables us to deduce the payload length.
900 st
->payload
= st
->len
- st
->pad
- 1;
902 pktin
.length
= st
->payload
+ 5;
905 * So now we can work out the total packet length.
907 st
->packetlen
= st
->len
+ 4;
908 st
->maclen
= scmac ? scmac
->len
: 0;
911 * Adjust memory allocation if packet is too big.
913 if (pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
914 pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
917 NULL ?
smalloc(pktin
.maxlen
+ APIEXTRA
) : srealloc(pktin
.data
,
922 fatalbox("Out of memory");
926 * Read and decrypt the remainder of the packet.
928 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
930 while ((*datalen
) == 0)
931 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
932 pktin
.data
[st
->i
] = *(*data
)++;
935 /* Decrypt everything _except_ the MAC. */
937 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
938 st
->packetlen
- st
->cipherblk
);
944 && !scmac
->verify(pktin
.data
, st
->len
+ 4,
945 st
->incoming_sequence
)) {
946 bombout(("Incorrect MAC received on packet"));
949 st
->incoming_sequence
++; /* whether or not we MACed */
952 * Decompress packet payload.
955 unsigned char *newpayload
;
957 if (sccomp
&& sccomp
->decompress(pktin
.data
+ 5, pktin
.length
- 5,
958 &newpayload
, &newlen
)) {
959 if (pktin
.maxlen
< newlen
+ 5) {
960 pktin
.maxlen
= newlen
+ 5;
963 NULL ?
smalloc(pktin
.maxlen
+
964 APIEXTRA
) : srealloc(pktin
.data
,
968 fatalbox("Out of memory");
970 pktin
.length
= 5 + newlen
;
971 memcpy(pktin
.data
+ 5, newpayload
, newlen
);
977 pktin
.type
= pktin
.data
[5];
979 log_packet(PKT_INCOMING
, pktin
.type
, ssh2_pkt_type(pktin
.type
),
980 pktin
.data
+6, pktin
.length
-6);
982 switch (pktin
.type
) {
984 * These packets we must handle instantly.
986 case SSH2_MSG_DISCONNECT
:
988 /* log reason code in disconnect message */
990 int reason
= GET_32BIT(pktin
.data
+ 6);
991 unsigned msglen
= GET_32BIT(pktin
.data
+ 10);
993 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
994 sprintf(buf
, "Received disconnect message (%s)",
995 ssh2_disconnect_reasons
[reason
]);
997 sprintf(buf
, "Received disconnect message (unknown type %d)",
1001 strcpy(buf
, "Disconnection message text: ");
1002 nowlen
= strlen(buf
);
1003 if (msglen
> sizeof(buf
) - nowlen
- 1)
1004 msglen
= sizeof(buf
) - nowlen
- 1;
1005 memcpy(buf
+ nowlen
, pktin
.data
+ 14, msglen
);
1006 buf
[nowlen
+ msglen
] = '\0';
1008 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1010 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1011 ssh2_disconnect_reasons
[reason
] : "unknown",
1016 case SSH2_MSG_IGNORE
:
1018 case SSH2_MSG_DEBUG
:
1020 /* log the debug message */
1022 /* int display = pktin.body[6]; */
1023 int stringlen
= GET_32BIT(pktin
.data
+7);
1025 strcpy(buf
, "Remote debug message: ");
1026 prefix
= strlen(buf
);
1027 if (stringlen
> sizeof(buf
)-prefix
-1)
1028 stringlen
= sizeof(buf
)-prefix
-1;
1029 memcpy(buf
+ prefix
, pktin
.data
+ 11, stringlen
);
1030 buf
[prefix
+ stringlen
] = '\0';
1033 goto next_packet
; /* FIXME: print the debug message */
1036 * These packets we need do nothing about here.
1038 case SSH2_MSG_UNIMPLEMENTED
:
1039 case SSH2_MSG_SERVICE_REQUEST
:
1040 case SSH2_MSG_SERVICE_ACCEPT
:
1041 case SSH2_MSG_KEXINIT
:
1042 case SSH2_MSG_NEWKEYS
:
1043 case SSH2_MSG_KEXDH_INIT
:
1044 case SSH2_MSG_KEXDH_REPLY
:
1045 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1046 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1047 case SSH2_MSG_KEX_DH_GEX_INIT
:
1048 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1049 case SSH2_MSG_USERAUTH_REQUEST
:
1050 case SSH2_MSG_USERAUTH_FAILURE
:
1051 case SSH2_MSG_USERAUTH_SUCCESS
:
1052 case SSH2_MSG_USERAUTH_BANNER
:
1053 case SSH2_MSG_USERAUTH_PK_OK
:
1054 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1055 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1056 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1057 case SSH2_MSG_GLOBAL_REQUEST
:
1058 case SSH2_MSG_REQUEST_SUCCESS
:
1059 case SSH2_MSG_REQUEST_FAILURE
:
1060 case SSH2_MSG_CHANNEL_OPEN
:
1061 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1062 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1063 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1064 case SSH2_MSG_CHANNEL_DATA
:
1065 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1066 case SSH2_MSG_CHANNEL_EOF
:
1067 case SSH2_MSG_CHANNEL_CLOSE
:
1068 case SSH2_MSG_CHANNEL_REQUEST
:
1069 case SSH2_MSG_CHANNEL_SUCCESS
:
1070 case SSH2_MSG_CHANNEL_FAILURE
:
1074 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1077 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
1078 ssh2_pkt_adduint32(st
->incoming_sequence
- 1);
1086 static void ssh1_pktout_size(int len
)
1090 len
+= 5; /* type and CRC */
1091 pad
= 8 - (len
% 8);
1094 pktout
.length
= len
- 5;
1095 if (pktout
.maxlen
< biglen
) {
1096 pktout
.maxlen
= biglen
;
1098 /* Allocate enough buffer space for extra block
1099 * for MS CryptEncrypt() */
1100 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 12) :
1101 srealloc(pktout
.data
, biglen
+ 12));
1103 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 4) :
1104 srealloc(pktout
.data
, biglen
+ 4));
1107 fatalbox("Out of memory");
1109 pktout
.body
= pktout
.data
+ 4 + pad
+ 1;
1112 static void s_wrpkt_start(int type
, int len
)
1114 ssh1_pktout_size(len
);
1118 static int s_wrpkt_prepare(void)
1120 int pad
, len
, biglen
, i
;
1123 pktout
.body
[-1] = pktout
.type
;
1125 log_packet(PKT_OUTGOING
, pktout
.type
, ssh1_pkt_type(pktout
.type
),
1126 pktout
.body
, pktout
.length
);
1128 if (ssh1_compressing
) {
1129 unsigned char *compblk
;
1131 zlib_compress_block(pktout
.body
- 1, pktout
.length
+ 1,
1132 &compblk
, &complen
);
1133 ssh1_pktout_size(complen
- 1);
1134 memcpy(pktout
.body
- 1, compblk
, complen
);
1138 len
= pktout
.length
+ 5; /* type and CRC */
1139 pad
= 8 - (len
% 8);
1142 for (i
= 0; i
< pad
; i
++)
1143 pktout
.data
[i
+ 4] = random_byte();
1144 crc
= crc32(pktout
.data
+ 4, biglen
- 4);
1145 PUT_32BIT(pktout
.data
+ biglen
, crc
);
1146 PUT_32BIT(pktout
.data
, len
);
1149 cipher
->encrypt(pktout
.data
+ 4, biglen
);
1154 static void s_wrpkt(void)
1157 len
= s_wrpkt_prepare();
1158 backlog
= sk_write(s
, pktout
.data
, len
);
1159 if (backlog
> SSH_MAX_BACKLOG
)
1160 ssh_throttle_all(1, backlog
);
1163 static void s_wrpkt_defer(void)
1166 len
= s_wrpkt_prepare();
1167 if (deferred_len
+ len
> deferred_size
) {
1168 deferred_size
= deferred_len
+ len
+ 128;
1169 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1171 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1172 deferred_len
+= len
;
1176 * Construct a packet with the specified contents.
1178 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
1180 unsigned char *p
, *argp
, argchar
;
1181 unsigned long argint
;
1182 int pktlen
, argtype
, arglen
;
1186 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1189 (void) va_arg(ap1
, int);
1193 (void) va_arg(ap1
, char);
1197 (void) va_arg(ap1
, unsigned char *);
1198 arglen
= va_arg(ap1
, int);
1202 argp
= va_arg(ap1
, unsigned char *);
1203 arglen
= strlen(argp
);
1204 pktlen
+= 4 + arglen
;
1207 bn
= va_arg(ap1
, Bignum
);
1208 pktlen
+= ssh1_bignum_length(bn
);
1215 s_wrpkt_start(pkttype
, pktlen
);
1218 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1221 argint
= va_arg(ap2
, int);
1222 PUT_32BIT(p
, argint
);
1226 argchar
= va_arg(ap2
, unsigned char);
1231 argp
= va_arg(ap2
, unsigned char *);
1232 arglen
= va_arg(ap2
, int);
1233 memcpy(p
, argp
, arglen
);
1237 argp
= va_arg(ap2
, unsigned char *);
1238 arglen
= strlen(argp
);
1239 PUT_32BIT(p
, arglen
);
1240 memcpy(p
+ 4, argp
, arglen
);
1244 bn
= va_arg(ap2
, Bignum
);
1245 p
+= ssh1_write_bignum(p
, bn
);
1251 static void send_packet(int pkttype
, ...)
1254 va_start(ap1
, pkttype
);
1255 va_start(ap2
, pkttype
);
1256 construct_packet(pkttype
, ap1
, ap2
);
1260 static void defer_packet(int pkttype
, ...)
1263 va_start(ap1
, pkttype
);
1264 va_start(ap2
, pkttype
);
1265 construct_packet(pkttype
, ap1
, ap2
);
1269 static int ssh_versioncmp(char *a
, char *b
)
1272 unsigned long av
, bv
;
1274 av
= strtoul(a
, &ae
, 10);
1275 bv
= strtoul(b
, &be
, 10);
1277 return (av
< bv ?
-1 : +1);
1282 av
= strtoul(ae
, &ae
, 10);
1283 bv
= strtoul(be
, &be
, 10);
1285 return (av
< bv ?
-1 : +1);
1291 * Utility routines for putting an SSH-protocol `string' and
1292 * `uint32' into a SHA state.
1295 static void sha_string(SHA_State
* s
, void *str
, int len
)
1297 unsigned char lenblk
[4];
1298 PUT_32BIT(lenblk
, len
);
1299 SHA_Bytes(s
, lenblk
, 4);
1300 SHA_Bytes(s
, str
, len
);
1303 static void sha_uint32(SHA_State
* s
, unsigned i
)
1305 unsigned char intblk
[4];
1306 PUT_32BIT(intblk
, i
);
1307 SHA_Bytes(s
, intblk
, 4);
1311 * SSH2 packet construction functions.
1313 static void ssh2_pkt_ensure(int length
)
1315 if (pktout
.maxlen
< length
) {
1316 pktout
.maxlen
= length
+ 256;
1319 NULL ?
smalloc(pktout
.maxlen
+
1320 APIEXTRA
) : srealloc(pktout
.data
,
1324 fatalbox("Out of memory");
1327 static void ssh2_pkt_adddata(void *data
, int len
)
1329 pktout
.length
+= len
;
1330 ssh2_pkt_ensure(pktout
.length
);
1331 memcpy(pktout
.data
+ pktout
.length
- len
, data
, len
);
1333 static void ssh2_pkt_addbyte(unsigned char byte
)
1335 ssh2_pkt_adddata(&byte
, 1);
1337 static void ssh2_pkt_init(int pkt_type
)
1340 ssh2_pkt_addbyte((unsigned char) pkt_type
);
1342 static void ssh2_pkt_addbool(unsigned char value
)
1344 ssh2_pkt_adddata(&value
, 1);
1346 static void ssh2_pkt_adduint32(unsigned long value
)
1349 PUT_32BIT(x
, value
);
1350 ssh2_pkt_adddata(x
, 4);
1352 static void ssh2_pkt_addstring_start(void)
1354 ssh2_pkt_adduint32(0);
1355 pktout
.savedpos
= pktout
.length
;
1357 static void ssh2_pkt_addstring_str(char *data
)
1359 ssh2_pkt_adddata(data
, strlen(data
));
1360 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1361 pktout
.length
- pktout
.savedpos
);
1363 static void ssh2_pkt_addstring_data(char *data
, int len
)
1365 ssh2_pkt_adddata(data
, len
);
1366 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1367 pktout
.length
- pktout
.savedpos
);
1369 static void ssh2_pkt_addstring(char *data
)
1371 ssh2_pkt_addstring_start();
1372 ssh2_pkt_addstring_str(data
);
1374 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1377 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1380 fatalbox("out of memory");
1382 for (i
= 1; i
<= n
; i
++)
1383 p
[i
] = bignum_byte(b
, n
- i
);
1385 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1387 memmove(p
, p
+ i
, n
+ 1 - i
);
1391 static void ssh2_pkt_addmp(Bignum b
)
1395 p
= ssh2_mpint_fmt(b
, &len
);
1396 ssh2_pkt_addstring_start();
1397 ssh2_pkt_addstring_data(p
, len
);
1402 * Construct an SSH2 final-form packet: compress it, encrypt it,
1403 * put the MAC on it. Final packet, ready to be sent, is stored in
1404 * pktout.data. Total length is returned.
1406 static int ssh2_pkt_construct(void)
1408 int cipherblk
, maclen
, padding
, i
;
1409 static unsigned long outgoing_sequence
= 0;
1411 log_packet(PKT_OUTGOING
, pktout
.data
[5], ssh2_pkt_type(pktout
.data
[5]),
1412 pktout
.data
+ 6, pktout
.length
- 6);
1415 * Compress packet payload.
1418 unsigned char *newpayload
;
1420 if (cscomp
&& cscomp
->compress(pktout
.data
+ 5, pktout
.length
- 5,
1421 &newpayload
, &newlen
)) {
1423 ssh2_pkt_adddata(newpayload
, newlen
);
1429 * Add padding. At least four bytes, and must also bring total
1430 * length (minus MAC) up to a multiple of the block size.
1432 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
1433 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1436 (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1437 maclen
= csmac ? csmac
->len
: 0;
1438 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
1439 pktout
.data
[4] = padding
;
1440 for (i
= 0; i
< padding
; i
++)
1441 pktout
.data
[pktout
.length
+ i
] = random_byte();
1442 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
1444 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
1446 outgoing_sequence
++; /* whether or not we MACed */
1449 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
1451 /* Ready-to-send packet starts at pktout.data. We return length. */
1452 return pktout
.length
+ padding
+ maclen
;
1456 * Construct and send an SSH2 packet immediately.
1458 static void ssh2_pkt_send(void)
1462 len
= ssh2_pkt_construct();
1463 backlog
= sk_write(s
, pktout
.data
, len
);
1464 if (backlog
> SSH_MAX_BACKLOG
)
1465 ssh_throttle_all(1, backlog
);
1469 * Construct an SSH2 packet and add it to a deferred data block.
1470 * Useful for sending multiple packets in a single sk_write() call,
1471 * to prevent a traffic-analysing listener from being able to work
1472 * out the length of any particular packet (such as the password
1475 * Note that because SSH2 sequence-numbers its packets, this can
1476 * NOT be used as an m4-style `defer' allowing packets to be
1477 * constructed in one order and sent in another.
1479 static void ssh2_pkt_defer(void)
1481 int len
= ssh2_pkt_construct();
1482 if (deferred_len
+ len
> deferred_size
) {
1483 deferred_size
= deferred_len
+ len
+ 128;
1484 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1486 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1487 deferred_len
+= len
;
1491 * Send the whole deferred data block constructed by
1492 * ssh2_pkt_defer() or SSH1's defer_packet().
1494 static void ssh_pkt_defersend(void)
1497 backlog
= sk_write(s
, deferred_send_data
, deferred_len
);
1498 deferred_len
= deferred_size
= 0;
1499 sfree(deferred_send_data
);
1500 deferred_send_data
= NULL
;
1501 if (backlog
> SSH_MAX_BACKLOG
)
1502 ssh_throttle_all(1, backlog
);
1506 void bndebug(char *string
, Bignum b
)
1510 p
= ssh2_mpint_fmt(b
, &len
);
1511 debug(("%s", string
));
1512 for (i
= 0; i
< len
; i
++)
1513 debug((" %02x", p
[i
]));
1519 static void sha_mpint(SHA_State
* s
, Bignum b
)
1523 p
= ssh2_mpint_fmt(b
, &len
);
1524 sha_string(s
, p
, len
);
1529 * SSH2 packet decode functions.
1531 static unsigned long ssh2_pkt_getuint32(void)
1533 unsigned long value
;
1534 if (pktin
.length
- pktin
.savedpos
< 4)
1535 return 0; /* arrgh, no way to decline (FIXME?) */
1536 value
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1537 pktin
.savedpos
+= 4;
1540 static int ssh2_pkt_getbool(void)
1542 unsigned long value
;
1543 if (pktin
.length
- pktin
.savedpos
< 1)
1544 return 0; /* arrgh, no way to decline (FIXME?) */
1545 value
= pktin
.data
[pktin
.savedpos
] != 0;
1549 static void ssh2_pkt_getstring(char **p
, int *length
)
1553 if (pktin
.length
- pktin
.savedpos
< 4)
1555 *length
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1556 pktin
.savedpos
+= 4;
1557 if (pktin
.length
- pktin
.savedpos
< *length
)
1559 *p
= pktin
.data
+ pktin
.savedpos
;
1560 pktin
.savedpos
+= *length
;
1562 static Bignum
ssh2_pkt_getmp(void)
1568 ssh2_pkt_getstring(&p
, &length
);
1572 bombout(("internal error: Can't handle negative mpints"));
1575 b
= bignum_from_bytes(p
, length
);
1580 * Helper function to add an SSH2 signature blob to a packet.
1581 * Expects to be shown the public key blob as well as the signature
1582 * blob. Normally works just like ssh2_pkt_addstring, but will
1583 * fiddle with the signature packet if necessary for
1584 * BUG_SSH2_RSA_PADDING.
1586 static void ssh2_add_sigblob(void *pkblob_v
, int pkblob_len
,
1587 void *sigblob_v
, int sigblob_len
)
1589 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1590 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1592 /* dmemdump(pkblob, pkblob_len); */
1593 /* dmemdump(sigblob, sigblob_len); */
1596 * See if this is in fact an ssh-rsa signature and a buggy
1597 * server; otherwise we can just do this the easy way.
1599 if ((ssh_remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1600 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1601 int pos
, len
, siglen
;
1604 * Find the byte length of the modulus.
1607 pos
= 4+7; /* skip over "ssh-rsa" */
1608 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1609 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1610 pos
+= 4; /* find modulus itself */
1611 while (len
> 0 && pkblob
[pos
] == 0)
1613 /* debug(("modulus length is %d\n", len)); */
1616 * Now find the signature integer.
1618 pos
= 4+7; /* skip over "ssh-rsa" */
1619 siglen
= GET_32BIT(sigblob
+pos
);
1620 /* debug(("signature length is %d\n", siglen)); */
1622 if (len
!= siglen
) {
1623 unsigned char newlen
[4];
1624 ssh2_pkt_addstring_start();
1625 ssh2_pkt_addstring_data(sigblob
, pos
);
1626 /* dmemdump(sigblob, pos); */
1627 pos
+= 4; /* point to start of actual sig */
1628 PUT_32BIT(newlen
, len
);
1629 ssh2_pkt_addstring_data(newlen
, 4);
1630 /* dmemdump(newlen, 4); */
1632 while (len
-- > siglen
) {
1633 ssh2_pkt_addstring_data(newlen
, 1);
1634 /* dmemdump(newlen, 1); */
1636 ssh2_pkt_addstring_data(sigblob
+pos
, siglen
);
1637 /* dmemdump(sigblob+pos, siglen); */
1641 /* Otherwise fall through and do it the easy way. */
1644 ssh2_pkt_addstring_start();
1645 ssh2_pkt_addstring_data(sigblob
, sigblob_len
);
1649 * Examine the remote side's version string and compare it against
1650 * a list of known buggy implementations.
1652 static void ssh_detect_bugs(char *vstring
)
1654 char *imp
; /* pointer to implementation part */
1656 imp
+= strcspn(imp
, "-");
1658 imp
+= strcspn(imp
, "-");
1661 ssh_remote_bugs
= 0;
1663 if (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1664 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1665 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")) {
1667 * These versions don't support SSH1_MSG_IGNORE, so we have
1668 * to use a different defence against password length
1671 ssh_remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1672 logevent("We believe remote version has SSH1 ignore bug");
1675 if (!strcmp(imp
, "Cisco-1.25")) {
1677 * These versions need a plain password sent; they can't
1678 * handle having a null and a random length of data after
1681 ssh_remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1682 logevent("We believe remote version needs a plain SSH1 password");
1685 if (!strcmp(imp
, "Cisco-1.25")) {
1687 * These versions apparently have no clue whatever about
1688 * RSA authentication and will panic and die if they see
1689 * an AUTH_RSA message.
1691 ssh_remote_bugs
|= BUG_CHOKES_ON_RSA
;
1692 logevent("We believe remote version can't handle RSA authentication");
1695 if (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1696 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1697 !strncmp(imp
, "2.1 ", 4)) {
1699 * These versions have the HMAC bug.
1701 ssh_remote_bugs
|= BUG_SSH2_HMAC
;
1702 logevent("We believe remote version has SSH2 HMAC bug");
1705 if (!strncmp(imp
, "2.0.", 4)) {
1707 * These versions have the key-derivation bug (failing to
1708 * include the literal shared secret in the hashes that
1709 * generate the keys).
1711 ssh_remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1712 logevent("We believe remote version has SSH2 key-derivation bug");
1715 if ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1716 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')) {
1718 * These versions have the SSH2 RSA padding bug.
1720 ssh_remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1721 logevent("We believe remote version has SSH2 RSA padding bug");
1725 static int do_ssh_init(unsigned char c
)
1728 static char version
[10];
1729 static char *vstring
;
1730 static int vstrsize
;
1733 static int proto1
, proto2
;
1737 /* Search for the string "SSH-" in the input. */
1740 static const int transS
[] = { 1, 2, 2, 1 };
1741 static const int transH
[] = { 0, 0, 3, 0 };
1742 static const int transminus
[] = { 0, 0, 0, -1 };
1753 crReturn(1); /* get another character */
1757 vstring
= smalloc(vstrsize
);
1758 strcpy(vstring
, "SSH-");
1762 crReturn(1); /* get another char */
1763 if (vslen
>= vstrsize
- 1) {
1765 vstring
= srealloc(vstring
, vstrsize
);
1767 vstring
[vslen
++] = c
;
1772 } else if (i
< sizeof(version
) - 1)
1774 } else if (c
== '\n')
1778 ssh_agentfwd_enabled
= FALSE
;
1779 rdpkt2_state
.incoming_sequence
= 0;
1782 vlog
= smalloc(20 + vslen
);
1783 vstring
[strcspn (vstring
, "\r\n")] = '\0'; /* remove end-of-line chars */
1784 sprintf(vlog
, "Server version: %s", vstring
);
1786 ssh_detect_bugs(vstring
);
1790 * Decide which SSH protocol version to support.
1793 /* Anything strictly below "2.0" means protocol 1 is supported. */
1794 proto1
= ssh_versioncmp(version
, "2.0") < 0;
1795 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1796 proto2
= ssh_versioncmp(version
, "1.99") >= 0;
1798 if (cfg
.sshprot
== 0 && !proto1
) {
1799 bombout(("SSH protocol version 1 required by user but not provided by server"));
1802 if (cfg
.sshprot
== 3 && !proto2
) {
1803 bombout(("SSH protocol version 2 required by user but not provided by server"));
1807 if (proto2
&& (cfg
.sshprot
>= 2 || !proto1
)) {
1811 char verstring
[80], vlog
[100];
1812 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1813 SHA_Init(&exhashbase
);
1815 * Hash our version string and their version string.
1817 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1818 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1819 sprintf(vlog
, "We claim version: %s", verstring
);
1821 strcat(verstring
, "\n");
1822 logevent("Using SSH protocol version 2");
1823 sk_write(s
, verstring
, strlen(verstring
));
1824 ssh_protocol
= ssh2_protocol
;
1826 s_rdpkt
= ssh2_rdpkt
;
1831 char verstring
[80], vlog
[100];
1832 sprintf(verstring
, "SSH-%s-%s",
1833 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"),
1835 sprintf(vlog
, "We claim version: %s", verstring
);
1837 strcat(verstring
, "\n");
1839 logevent("Using SSH protocol version 1");
1840 sk_write(s
, verstring
, strlen(verstring
));
1841 ssh_protocol
= ssh1_protocol
;
1843 s_rdpkt
= ssh1_rdpkt
;
1845 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1852 static void ssh_gotdata(unsigned char *data
, int datalen
)
1857 * To begin with, feed the characters one by one to the
1858 * protocol initialisation / selection function do_ssh_init().
1859 * When that returns 0, we're done with the initial greeting
1860 * exchange and can move on to packet discipline.
1865 crReturnV
; /* more data please */
1866 ret
= do_ssh_init(*data
);
1874 * We emerge from that loop when the initial negotiation is
1875 * over and we have selected an s_rdpkt function. Now pass
1876 * everything to s_rdpkt, and then pass the resulting packets
1877 * to the proper protocol handler.
1882 while (datalen
> 0) {
1883 if (s_rdpkt(&data
, &datalen
) == 0) {
1884 if (ssh_state
== SSH_STATE_CLOSED
) {
1887 ssh_protocol(NULL
, 0, 1);
1888 if (ssh_state
== SSH_STATE_CLOSED
) {
1898 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1901 ssh_state
= SSH_STATE_CLOSED
;
1907 /* A socket error has occurred. */
1908 logevent(error_msg
);
1909 connection_fatal(error_msg
);
1911 /* Otherwise, the remote side closed the connection normally. */
1916 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1918 ssh_gotdata(data
, len
);
1919 if (ssh_state
== SSH_STATE_CLOSED
) {
1929 static void ssh_sent(Plug plug
, int bufsize
)
1932 * If the send backlog on the SSH socket itself clears, we
1933 * should unthrottle the whole world if it was throttled.
1935 if (bufsize
< SSH_MAX_BACKLOG
)
1936 ssh_throttle_all(0, bufsize
);
1940 * Connect to specified host and port.
1941 * Returns an error message, or NULL on success.
1942 * Also places the canonical host name into `realhost'. It must be
1943 * freed by the caller.
1945 static char *connect_to_host(char *host
, int port
, char **realhost
, int nodelay
)
1947 static struct plug_function_table fn_table
= {
1952 }, *fn_table_ptr
= &fn_table
;
1961 savedhost
= smalloc(1 + strlen(host
));
1963 fatalbox("Out of memory");
1964 strcpy(savedhost
, host
);
1967 port
= 22; /* default ssh port */
1982 sprintf(buf
, "Looking up host \"%.170s\"", host
);
1985 addr
= sk_namelookup(host
, realhost
);
1986 if ((err
= sk_addr_error(addr
)))
1990 *realhost
= strdup(FWhost
);
1997 char buf
[200], addrbuf
[100];
1998 sk_getaddr(addr
, addrbuf
, 100);
1999 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
2002 s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, &fn_table_ptr
);
2003 if ((err
= sk_socket_error(s
))) {
2009 sk_write(s
, "connect ", 8);
2010 sk_write(s
, FWhost
, strlen(FWhost
));
2013 sprintf(buf
, " %d\n", FWport
);
2014 sk_write(s
, buf
, strlen(buf
));
2022 * Throttle or unthrottle the SSH connection.
2024 static void ssh1_throttle(int adjust
)
2026 int old_count
= ssh1_throttle_count
;
2027 ssh1_throttle_count
+= adjust
;
2028 assert(ssh1_throttle_count
>= 0);
2029 if (ssh1_throttle_count
&& !old_count
) {
2030 sk_set_frozen(s
, 1);
2031 } else if (!ssh1_throttle_count
&& old_count
) {
2032 sk_set_frozen(s
, 0);
2037 * Throttle or unthrottle _all_ local data streams (for when sends
2038 * on the SSH connection itself back up).
2040 static void ssh_throttle_all(int enable
, int bufsize
)
2043 struct ssh_channel
*c
;
2045 if (enable
== ssh_throttled_all
)
2047 ssh_throttled_all
= enable
;
2048 ssh_overall_bufsize
= bufsize
;
2051 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
2053 case CHAN_MAINSESSION
:
2055 * This is treated separately, outside the switch.
2059 x11_override_throttle(c
->u
.x11
.s
, enable
);
2062 /* Agent channels require no buffer management. */
2065 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2072 * Username and password input, abstracted off into reusable
2073 * routines (hopefully even reusable between SSH1 and SSH2!).
2075 static char *ssh_userpass_input_buffer
;
2076 static int ssh_userpass_input_buflen
;
2077 static int ssh_userpass_input_bufpos
;
2078 static int ssh_userpass_input_echo
;
2080 /* Set up a username or password input loop on a given buffer. */
2081 void setup_userpass_input(char *buffer
, int buflen
, int echo
)
2083 ssh_userpass_input_buffer
= buffer
;
2084 ssh_userpass_input_buflen
= buflen
;
2085 ssh_userpass_input_bufpos
= 0;
2086 ssh_userpass_input_echo
= echo
;
2090 * Process some terminal data in the course of username/password
2091 * input. Returns >0 for success (line of input returned in
2092 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2093 * for inconclusive (keep waiting for more input please).
2095 int process_userpass_input(unsigned char *in
, int inlen
)
2100 switch (c
= *in
++) {
2103 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
] = 0;
2104 ssh_userpass_input_buffer
[ssh_userpass_input_buflen
-1] = 0;
2109 if (ssh_userpass_input_bufpos
> 0) {
2110 if (ssh_userpass_input_echo
)
2111 c_write_str("\b \b");
2112 ssh_userpass_input_bufpos
--;
2117 while (ssh_userpass_input_bufpos
> 0) {
2118 if (ssh_userpass_input_echo
)
2119 c_write_str("\b \b");
2120 ssh_userpass_input_bufpos
--;
2128 if (((c
>= ' ' && c
<= '~') ||
2129 ((unsigned char) c
>= 160))
2130 && ssh_userpass_input_bufpos
< ssh_userpass_input_buflen
-1) {
2131 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
++] = c
;
2132 if (ssh_userpass_input_echo
)
2142 * Handle the key exchange and user authentication phases.
2144 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
2148 static unsigned char *rsabuf
, *keystr1
, *keystr2
;
2149 unsigned char cookie
[8];
2150 struct RSAKey servkey
, hostkey
;
2151 struct MD5Context md5c
;
2152 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
2153 static int tried_publickey
, tried_agent
;
2154 static int tis_auth_refused
, ccard_auth_refused
;
2155 static unsigned char session_id
[16];
2156 static int cipher_type
;
2157 static char username
[100];
2158 static void *publickey_blob
;
2159 int publickey_bloblen
;
2166 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2167 bombout(("Public key packet not received"));
2171 logevent("Received public keys");
2173 memcpy(cookie
, pktin
.body
, 8);
2175 i
= makekey(pktin
.body
+ 8, &servkey
, &keystr1
, 0);
2176 j
= makekey(pktin
.body
+ 8 + i
, &hostkey
, &keystr2
, 0);
2179 * Log the host key fingerprint.
2183 logevent("Host key fingerprint is:");
2184 strcpy(logmsg
, " ");
2185 hostkey
.comment
= NULL
;
2186 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2187 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2191 ssh1_remote_protoflags
= GET_32BIT(pktin
.body
+ 8 + i
+ j
);
2192 supported_ciphers_mask
= GET_32BIT(pktin
.body
+ 12 + i
+ j
);
2193 supported_auths_mask
= GET_32BIT(pktin
.body
+ 16 + i
+ j
);
2195 ssh1_local_protoflags
=
2196 ssh1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2197 ssh1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2200 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
2201 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
2202 MD5Update(&md5c
, pktin
.body
, 8);
2203 MD5Final(session_id
, &md5c
);
2205 for (i
= 0; i
< 32; i
++)
2206 session_key
[i
] = random_byte();
2208 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2210 rsabuf
= smalloc(len
);
2212 fatalbox("Out of memory");
2215 * Verify the host key.
2219 * First format the key into a string.
2221 int len
= rsastr_len(&hostkey
);
2222 char fingerprint
[100];
2223 char *keystr
= smalloc(len
);
2225 fatalbox("Out of memory");
2226 rsastr_fmt(keystr
, &hostkey
);
2227 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2228 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
,
2233 for (i
= 0; i
< 32; i
++) {
2234 rsabuf
[i
] = session_key
[i
];
2236 rsabuf
[i
] ^= session_id
[i
];
2239 if (hostkey
.bytes
> servkey
.bytes
) {
2240 rsaencrypt(rsabuf
, 32, &servkey
);
2241 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
2243 rsaencrypt(rsabuf
, 32, &hostkey
);
2244 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
2247 logevent("Encrypted session key");
2250 int cipher_chosen
= 0, warn
= 0;
2251 char *cipher_string
= NULL
;
2252 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2253 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2254 if (next_cipher
== CIPHER_WARN
) {
2255 /* If/when we choose a cipher, warn about it */
2257 } else if (next_cipher
== CIPHER_AES
) {
2258 /* XXX Probably don't need to mention this. */
2259 logevent("AES not supported in SSH1, skipping");
2261 switch (next_cipher
) {
2262 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
;
2263 cipher_string
= "3DES"; break;
2264 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
;
2265 cipher_string
= "Blowfish"; break;
2266 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
;
2267 cipher_string
= "single-DES"; break;
2269 if (supported_ciphers_mask
& (1 << cipher_type
))
2273 if (!cipher_chosen
) {
2274 if ((supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2275 bombout(("Server violates SSH 1 protocol by not "
2276 "supporting 3DES encryption"));
2278 /* shouldn't happen */
2279 bombout(("No supported ciphers found"));
2283 /* Warn about chosen cipher if necessary. */
2285 askcipher(cipher_string
, 0);
2288 switch (cipher_type
) {
2289 case SSH_CIPHER_3DES
:
2290 logevent("Using 3DES encryption");
2292 case SSH_CIPHER_DES
:
2293 logevent("Using single-DES encryption");
2295 case SSH_CIPHER_BLOWFISH
:
2296 logevent("Using Blowfish encryption");
2300 send_packet(SSH1_CMSG_SESSION_KEY
,
2301 PKT_CHAR
, cipher_type
,
2302 PKT_DATA
, cookie
, 8,
2303 PKT_CHAR
, (len
* 8) >> 8, PKT_CHAR
, (len
* 8) & 0xFF,
2304 PKT_DATA
, rsabuf
, len
,
2305 PKT_INT
, ssh1_local_protoflags
, PKT_END
);
2307 logevent("Trying to enable encryption...");
2311 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2312 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
: &ssh_3des
;
2313 cipher
->sesskey(session_key
);
2317 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2318 bombout(("Encryption not successfully enabled"));
2322 logevent("Successfully started encryption");
2326 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2327 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2328 if (!ssh_get_line("login as: ",
2329 username
, sizeof(username
), FALSE
)) {
2331 * get_line failed to get a username.
2334 logevent("No username provided. Abandoning session.");
2335 ssh_state
= SSH_STATE_CLOSED
;
2340 c_write_str("login as: ");
2343 setup_userpass_input(username
, sizeof(username
), 1);
2345 crWaitUntil(!ispkt
);
2346 ret
= process_userpass_input(in
, inlen
);
2350 c_write_str("\r\n");
2353 strncpy(username
, cfg
.username
, 99);
2354 username
[99] = '\0';
2357 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
2359 char userlog
[22 + sizeof(username
)];
2360 sprintf(userlog
, "Sent username \"%s\"", username
);
2362 if (flags
& FLAG_INTERACTIVE
&&
2363 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2364 strcat(userlog
, "\r\n");
2365 c_write_str(userlog
);
2372 if ((ssh_remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2373 /* We must not attempt PK auth. Pretend we've already tried it. */
2374 tried_publickey
= tried_agent
= 1;
2376 tried_publickey
= tried_agent
= 0;
2378 tis_auth_refused
= ccard_auth_refused
= 0;
2379 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2381 if (!rsakey_pubblob(cfg
.keyfile
, &publickey_blob
, &publickey_bloblen
))
2382 publickey_blob
= NULL
;
2384 publickey_blob
= NULL
;
2386 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
2387 static char password
[100];
2388 static char prompt
[200];
2391 static int pwpkt_type
;
2392 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2394 if (agent_exists() && !tried_agent
) {
2396 * Attempt RSA authentication using Pageant.
2398 static unsigned char request
[5], *response
, *p
;
2399 static int responselen
;
2400 static int i
, nkeys
;
2401 static int authed
= FALSE
;
2405 logevent("Pageant is running. Requesting keys.");
2407 /* Request the keys held by the agent. */
2408 PUT_32BIT(request
, 1);
2409 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2410 agent_query(request
, 5, &r
, &responselen
);
2411 response
= (unsigned char *) r
;
2412 if (response
&& responselen
>= 5 &&
2413 response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2415 nkeys
= GET_32BIT(p
);
2419 sprintf(buf
, "Pageant has %d SSH1 keys", nkeys
);
2422 for (i
= 0; i
< nkeys
; i
++) {
2423 static struct RSAKey key
;
2424 static Bignum challenge
;
2425 static char *commentp
;
2426 static int commentlen
;
2430 sprintf(buf
, "Trying Pageant key #%d", i
);
2433 if (publickey_blob
&&
2434 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
2435 logevent("This key matches configured key file");
2436 tried_publickey
= 1;
2439 p
+= ssh1_read_bignum(p
, &key
.exponent
);
2440 p
+= ssh1_read_bignum(p
, &key
.modulus
);
2441 commentlen
= GET_32BIT(p
);
2445 send_packet(SSH1_CMSG_AUTH_RSA
,
2446 PKT_BIGNUM
, key
.modulus
, PKT_END
);
2448 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2449 logevent("Key refused");
2452 logevent("Received RSA challenge");
2453 ssh1_read_bignum(pktin
.body
, &challenge
);
2455 char *agentreq
, *q
, *ret
;
2458 len
= 1 + 4; /* message type, bit count */
2459 len
+= ssh1_bignum_length(key
.exponent
);
2460 len
+= ssh1_bignum_length(key
.modulus
);
2461 len
+= ssh1_bignum_length(challenge
);
2462 len
+= 16; /* session id */
2463 len
+= 4; /* response format */
2464 agentreq
= smalloc(4 + len
);
2465 PUT_32BIT(agentreq
, len
);
2467 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2468 PUT_32BIT(q
, bignum_bitcount(key
.modulus
));
2470 q
+= ssh1_write_bignum(q
, key
.exponent
);
2471 q
+= ssh1_write_bignum(q
, key
.modulus
);
2472 q
+= ssh1_write_bignum(q
, challenge
);
2473 memcpy(q
, session_id
, 16);
2475 PUT_32BIT(q
, 1); /* response format */
2476 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2480 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2481 logevent("Sending Pageant's response");
2482 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2483 PKT_DATA
, ret
+ 5, 16,
2487 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2489 ("Pageant's response accepted");
2490 if (flags
& FLAG_VERBOSE
) {
2492 ("Authenticated using RSA key \"");
2493 c_write(commentp
, commentlen
);
2494 c_write_str("\" from agent\r\n");
2499 ("Pageant's response not accepted");
2502 ("Pageant failed to answer challenge");
2506 logevent("No reply received from Pageant");
2509 freebn(key
.exponent
);
2510 freebn(key
.modulus
);
2519 if (*cfg
.keyfile
&& !tried_publickey
)
2520 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2522 if (cfg
.try_tis_auth
&&
2523 (supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2524 !tis_auth_refused
) {
2525 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2526 logevent("Requested TIS authentication");
2527 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
2529 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2530 logevent("TIS authentication declined");
2531 if (flags
& FLAG_INTERACTIVE
)
2532 c_write_str("TIS authentication refused.\r\n");
2533 tis_auth_refused
= 1;
2536 int challengelen
= ((pktin
.body
[0] << 24) |
2537 (pktin
.body
[1] << 16) |
2538 (pktin
.body
[2] << 8) |
2540 logevent("Received TIS challenge");
2541 if (challengelen
> sizeof(prompt
) - 1)
2542 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2543 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2544 /* Prompt heuristic comes from OpenSSH */
2545 strncpy(prompt
+ challengelen
,
2546 memchr(prompt
, '\n', challengelen
) ?
2547 "": "\r\nResponse: ",
2548 (sizeof prompt
) - challengelen
);
2549 prompt
[(sizeof prompt
) - 1] = '\0';
2552 if (cfg
.try_tis_auth
&&
2553 (supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2554 !ccard_auth_refused
) {
2555 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2556 logevent("Requested CryptoCard authentication");
2557 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2559 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2560 logevent("CryptoCard authentication declined");
2561 c_write_str("CryptoCard authentication refused.\r\n");
2562 ccard_auth_refused
= 1;
2565 int challengelen
= ((pktin
.body
[0] << 24) |
2566 (pktin
.body
[1] << 16) |
2567 (pktin
.body
[2] << 8) |
2569 logevent("Received CryptoCard challenge");
2570 if (challengelen
> sizeof(prompt
) - 1)
2571 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2572 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2573 strncpy(prompt
+ challengelen
,
2574 memchr(prompt
, '\n', challengelen
) ?
2575 "" : "\r\nResponse: ",
2576 sizeof(prompt
) - challengelen
);
2577 prompt
[sizeof(prompt
) - 1] = '\0';
2580 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2581 sprintf(prompt
, "%.90s@%.90s's password: ",
2582 username
, savedhost
);
2584 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2585 char *comment
= NULL
;
2588 if (flags
& FLAG_VERBOSE
)
2589 c_write_str("Trying public key authentication.\r\n");
2590 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2592 type
= key_type(cfg
.keyfile
);
2593 if (type
!= SSH_KEYTYPE_SSH1
) {
2594 sprintf(msgbuf
, "Key is of wrong type (%s)",
2595 key_type_to_str(type
));
2597 c_write_str(msgbuf
);
2598 c_write_str("\r\n");
2599 tried_publickey
= 1;
2602 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2603 if (flags
& FLAG_VERBOSE
)
2604 c_write_str("No passphrase required.\r\n");
2607 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
2612 * Show password prompt, having first obtained it via a TIS
2613 * or CryptoCard exchange if we're doing TIS or CryptoCard
2617 if (!ssh_get_line(prompt
, password
, sizeof(password
), TRUE
)) {
2619 * get_line failed to get a password (for example
2620 * because one was supplied on the command line
2621 * which has already failed to work). Terminate.
2623 send_packet(SSH1_MSG_DISCONNECT
,
2624 PKT_STR
, "No more passwords available to try",
2626 logevent("Unable to authenticate");
2627 connection_fatal("Unable to authenticate");
2628 ssh_state
= SSH_STATE_CLOSED
;
2632 /* Prompt may have come from server. We've munged it a bit, so
2633 * we know it to be zero-terminated at least once. */
2635 c_write_untrusted(prompt
, strlen(prompt
));
2638 setup_userpass_input(password
, sizeof(password
), 0);
2640 crWaitUntil(!ispkt
);
2641 ret
= process_userpass_input(in
, inlen
);
2645 c_write_str("\r\n");
2649 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2651 * Try public key authentication with the specified
2654 static struct RSAKey pubkey
;
2655 static Bignum challenge
, response
;
2657 static unsigned char buffer
[32];
2659 tried_publickey
= 1;
2660 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
2662 c_write_str("Couldn't load private key from ");
2663 c_write_str(cfg
.keyfile
);
2664 c_write_str(".\r\n");
2665 continue; /* go and try password */
2668 c_write_str("Wrong passphrase.\r\n");
2669 tried_publickey
= 0;
2670 continue; /* try again */
2674 * Send a public key attempt.
2676 send_packet(SSH1_CMSG_AUTH_RSA
,
2677 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
2680 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2681 c_write_str("Server refused our public key.\r\n");
2682 continue; /* go and try password */
2684 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2685 bombout(("Bizarre response to offer of public key"));
2688 ssh1_read_bignum(pktin
.body
, &challenge
);
2689 response
= rsadecrypt(challenge
, &pubkey
);
2690 freebn(pubkey
.private_exponent
); /* burn the evidence */
2692 for (i
= 0; i
< 32; i
++) {
2693 buffer
[i
] = bignum_byte(response
, 31 - i
);
2697 MD5Update(&md5c
, buffer
, 32);
2698 MD5Update(&md5c
, session_id
, 16);
2699 MD5Final(buffer
, &md5c
);
2701 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2702 PKT_DATA
, buffer
, 16, PKT_END
);
2705 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2706 if (flags
& FLAG_VERBOSE
)
2708 ("Failed to authenticate with our public key.\r\n");
2709 continue; /* go and try password */
2710 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2712 ("Bizarre response to RSA authentication response"));
2716 break; /* we're through! */
2718 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2720 * Defence against traffic analysis: we send a
2721 * whole bunch of packets containing strings of
2722 * different lengths. One of these strings is the
2723 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2724 * The others are all random data in
2725 * SSH1_MSG_IGNORE packets. This way a passive
2726 * listener can't tell which is the password, and
2727 * hence can't deduce the password length.
2729 * Anybody with a password length greater than 16
2730 * bytes is going to have enough entropy in their
2731 * password that a listener won't find it _that_
2732 * much help to know how long it is. So what we'll
2735 * - if password length < 16, we send 15 packets
2736 * containing string lengths 1 through 15
2738 * - otherwise, we let N be the nearest multiple
2739 * of 8 below the password length, and send 8
2740 * packets containing string lengths N through
2741 * N+7. This won't obscure the order of
2742 * magnitude of the password length, but it will
2743 * introduce a bit of extra uncertainty.
2745 * A few servers (the old 1.2.18 through 1.2.22)
2746 * can't deal with SSH1_MSG_IGNORE. For these
2747 * servers, we need an alternative defence. We make
2748 * use of the fact that the password is interpreted
2749 * as a C string: so we can append a NUL, then some
2752 * One server (a Cisco one) can deal with neither
2753 * SSH1_MSG_IGNORE _nor_ a padded password string.
2754 * For this server we are left with no defences
2755 * against password length sniffing.
2757 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2759 * The server can deal with SSH1_MSG_IGNORE, so
2760 * we can use the primary defence.
2762 int bottom
, top
, pwlen
, i
;
2765 pwlen
= strlen(password
);
2767 bottom
= 0; /* zero length passwords are OK! :-) */
2770 bottom
= pwlen
& ~7;
2774 assert(pwlen
>= bottom
&& pwlen
<= top
);
2776 randomstr
= smalloc(top
+ 1);
2778 for (i
= bottom
; i
<= top
; i
++) {
2780 defer_packet(pwpkt_type
, PKT_STR
, password
,
2783 for (j
= 0; j
< i
; j
++) {
2785 randomstr
[j
] = random_byte();
2786 } while (randomstr
[j
] == '\0');
2788 randomstr
[i
] = '\0';
2789 defer_packet(SSH1_MSG_IGNORE
,
2790 PKT_STR
, randomstr
, PKT_END
);
2793 logevent("Sending password with camouflage packets");
2794 ssh_pkt_defersend();
2796 else if (!(ssh_remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2798 * The server can't deal with SSH1_MSG_IGNORE
2799 * but can deal with padded passwords, so we
2800 * can use the secondary defence.
2806 len
= strlen(password
);
2807 if (len
< sizeof(string
)) {
2809 strcpy(string
, password
);
2810 len
++; /* cover the zero byte */
2811 while (len
< sizeof(string
)) {
2812 string
[len
++] = (char) random_byte();
2817 logevent("Sending length-padded password");
2818 send_packet(pwpkt_type
, PKT_INT
, len
,
2819 PKT_DATA
, s
, len
, PKT_END
);
2822 * The server has _both_
2823 * BUG_CHOKES_ON_SSH1_IGNORE and
2824 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2825 * therefore nothing we can do.
2828 len
= strlen(password
);
2829 logevent("Sending unpadded password");
2830 send_packet(pwpkt_type
, PKT_INT
, len
,
2831 PKT_DATA
, password
, len
, PKT_END
);
2834 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
2837 logevent("Sent password");
2838 memset(password
, 0, strlen(password
));
2840 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2841 if (flags
& FLAG_VERBOSE
)
2842 c_write_str("Access denied\r\n");
2843 logevent("Authentication refused");
2844 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2845 logevent("Received disconnect request");
2846 ssh_state
= SSH_STATE_CLOSED
;
2848 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2849 bombout(("Strange packet received, type %d", pktin
.type
));
2854 logevent("Authentication successful");
2859 void sshfwd_close(struct ssh_channel
*c
)
2861 if (c
&& !c
->closes
) {
2863 * If the channel's remoteid is -1, we have sent
2864 * CHANNEL_OPEN for this channel, but it hasn't even been
2865 * acknowledged by the server. So we must set a close flag
2866 * on it now, and then when the server acks the channel
2867 * open, we can close it then.
2869 if (((int)c
->remoteid
) != -1) {
2870 if (ssh_version
== 1) {
2871 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2874 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2875 ssh2_pkt_adduint32(c
->remoteid
);
2880 if (c
->type
== CHAN_X11
) {
2882 logevent("Forwarded X11 connection terminated");
2883 } else if (c
->type
== CHAN_SOCKDATA
||
2884 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2886 logevent("Forwarded port closed");
2891 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2893 if (ssh_version
== 1) {
2894 send_packet(SSH1_MSG_CHANNEL_DATA
,
2895 PKT_INT
, c
->remoteid
,
2896 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2898 * In SSH1 we can return 0 here - implying that forwarded
2899 * connections are never individually throttled - because
2900 * the only circumstance that can cause throttling will be
2901 * the whole SSH connection backing up, in which case
2902 * _everything_ will be throttled as a whole.
2906 ssh2_add_channel_data(c
, buf
, len
);
2907 return ssh2_try_send(c
);
2911 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2913 if (ssh_version
== 1) {
2914 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2915 c
->v
.v1
.throttling
= 0;
2919 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
2923 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
)
2929 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
2932 if (ssh_state
== SSH_STATE_CLOSED
)
2935 if (cfg
.agentfwd
&& agent_exists()) {
2936 logevent("Requesting agent forwarding");
2937 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
2941 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2942 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2943 bombout(("Protocol confusion"));
2945 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2946 logevent("Agent forwarding refused");
2948 logevent("Agent forwarding enabled");
2949 ssh_agentfwd_enabled
= TRUE
;
2953 if (cfg
.x11_forward
) {
2954 char proto
[20], data
[64];
2955 logevent("Requesting X11 forwarding");
2956 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2957 if (ssh1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
2958 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2959 PKT_STR
, proto
, PKT_STR
, data
,
2960 PKT_INT
, 0, PKT_END
);
2962 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2963 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
2968 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2969 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2970 bombout(("Protocol confusion"));
2972 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2973 logevent("X11 forwarding refused");
2975 logevent("X11 forwarding enabled");
2976 ssh_X11_fwd_enabled
= TRUE
;
2984 int sport
,dport
,sserv
,dserv
;
2985 char sports
[256], dports
[256], host
[256];
2989 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh1
);
2990 /* Add port forwardings. */
2995 while (*e
&& *e
!= '\t')
3001 while (*e
&& *e
!= ':')
3011 dport
= atoi(dports
);
3015 se
= getservbyname(dports
, NULL
);
3017 dport
= ntohs(se
->s_port
);
3020 "Service lookup failed for destination port \"%s\"",
3025 sport
= atoi(sports
);
3029 se
= getservbyname(sports
, NULL
);
3031 sport
= ntohs(se
->s_port
);
3034 "Service lookup failed for source port \"%s\"",
3039 if (sport
&& dport
) {
3041 pfd_addforward(host
, dport
, sport
);
3042 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3043 " %s:%.*s%.*s%d%.*s",
3044 sserv ?
strlen(sports
) : 0, sports
,
3045 sserv
, "(", sport
, sserv
, ")",
3047 dserv ?
strlen(dports
) : 0, dports
,
3048 dserv
, "(", dport
, dserv
, ")");
3051 struct ssh_rportfwd
*pf
;
3052 pf
= smalloc(sizeof(*pf
));
3053 strcpy(pf
->dhost
, host
);
3055 if (add234(ssh_rportfwds
, pf
) != pf
) {
3057 "Duplicate remote port forwarding to %s:%d",
3062 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3063 " forward to %s:%.*s%.*s%d%.*s",
3064 sserv ?
strlen(sports
) : 0, sports
,
3065 sserv
, "(", sport
, sserv
, ")",
3067 dserv ?
strlen(dports
) : 0, dports
,
3068 dserv
, "(", dport
, dserv
, ")");
3070 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST
,
3078 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3079 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3080 bombout(("Protocol confusion"));
3082 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3083 c_write_str("Server refused port forwarding\r\n");
3084 ssh_editing
= ssh_echoing
= 1;
3086 logevent("Remote port forwarding enabled");
3094 send_packet(SSH1_CMSG_REQUEST_PTY
,
3095 PKT_STR
, cfg
.termtype
,
3096 PKT_INT
, rows
, PKT_INT
, cols
,
3097 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3098 ssh_state
= SSH_STATE_INTERMED
;
3102 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3103 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3104 bombout(("Protocol confusion"));
3106 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3107 c_write_str("Server refused to allocate pty\r\n");
3108 ssh_editing
= ssh_echoing
= 1;
3110 logevent("Allocated pty");
3112 ssh_editing
= ssh_echoing
= 1;
3115 if (cfg
.compression
) {
3116 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3120 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3121 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3122 bombout(("Protocol confusion"));
3124 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3125 c_write_str("Server refused to compress\r\n");
3127 logevent("Started compression");
3128 ssh1_compressing
= TRUE
;
3129 zlib_compress_init();
3130 zlib_decompress_init();
3134 * Start the shell or command.
3136 * Special case: if the first-choice command is an SSH2
3137 * subsystem (hence not usable here) and the second choice
3138 * exists, we fall straight back to that.
3141 char *cmd
= cfg
.remote_cmd_ptr
;
3143 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3144 cmd
= cfg
.remote_cmd_ptr2
;
3145 ssh_fallback_cmd
= TRUE
;
3148 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3150 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3151 logevent("Started session");
3154 ssh_state
= SSH_STATE_SESSION
;
3158 ssh_special(TS_EOF
);
3160 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
3162 ssh_channels
= newtree234(ssh_channelcmp
);
3166 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3167 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3168 long len
= GET_32BIT(pktin
.body
);
3170 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3171 pktin
.body
+ 4, len
);
3172 if (!ssh1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3173 ssh1_stdout_throttling
= 1;
3176 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
3177 ssh_state
= SSH_STATE_CLOSED
;
3178 logevent("Received disconnect request");
3180 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3181 /* Remote side is trying to open a channel to talk to our
3182 * X-Server. Give them back a local channel number. */
3183 struct ssh_channel
*c
;
3185 logevent("Received X11 connect request");
3186 /* Refuse if X11 forwarding is disabled. */
3187 if (!ssh_X11_fwd_enabled
) {
3188 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3189 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3190 logevent("Rejected X11 connect request");
3192 c
= smalloc(sizeof(struct ssh_channel
));
3194 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3195 logevent("opening X11 forward connection failed");
3197 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3198 PKT_INT
, GET_32BIT(pktin
.body
),
3202 ("opening X11 forward connection succeeded");
3203 c
->remoteid
= GET_32BIT(pktin
.body
);
3204 c
->localid
= alloc_channel_id();
3206 c
->v
.v1
.throttling
= 0;
3207 c
->type
= CHAN_X11
; /* identify channel type */
3208 add234(ssh_channels
, c
);
3209 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3210 PKT_INT
, c
->remoteid
, PKT_INT
,
3211 c
->localid
, PKT_END
);
3212 logevent("Opened X11 forward channel");
3215 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3216 /* Remote side is trying to open a channel to talk to our
3217 * agent. Give them back a local channel number. */
3218 struct ssh_channel
*c
;
3220 /* Refuse if agent forwarding is disabled. */
3221 if (!ssh_agentfwd_enabled
) {
3222 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3223 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3225 c
= smalloc(sizeof(struct ssh_channel
));
3226 c
->remoteid
= GET_32BIT(pktin
.body
);
3227 c
->localid
= alloc_channel_id();
3229 c
->v
.v1
.throttling
= 0;
3230 c
->type
= CHAN_AGENT
; /* identify channel type */
3231 c
->u
.a
.lensofar
= 0;
3232 add234(ssh_channels
, c
);
3233 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3234 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3237 } else if (pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3238 /* Remote side is trying to open a channel to talk to a
3239 * forwarded port. Give them back a local channel number. */
3240 struct ssh_channel
*c
;
3241 struct ssh_rportfwd pf
;
3243 char host
[256], buf
[1024];
3245 c
= smalloc(sizeof(struct ssh_channel
));
3247 hostsize
= GET_32BIT(pktin
.body
+4);
3248 for(h
= host
, p
= pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3249 if (h
+1 < host
+sizeof(host
))
3254 port
= GET_32BIT(p
);
3256 strcpy(pf
.dhost
, host
);
3259 if (find234(ssh_rportfwds
, &pf
, NULL
) == NULL
) {
3260 sprintf(buf
, "Rejected remote port open request for %s:%d",
3263 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3264 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3266 sprintf(buf
, "Received remote port open request for %s:%d",
3269 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3272 sprintf(buf
, "Port open failed: %s", e
);
3275 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3276 PKT_INT
, GET_32BIT(pktin
.body
),
3279 c
->remoteid
= GET_32BIT(pktin
.body
);
3280 c
->localid
= alloc_channel_id();
3282 c
->v
.v1
.throttling
= 0;
3283 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3284 add234(ssh_channels
, c
);
3285 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3286 PKT_INT
, c
->remoteid
, PKT_INT
,
3287 c
->localid
, PKT_END
);
3288 logevent("Forwarded port opened successfully");
3292 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3293 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3294 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3295 struct ssh_channel
*c
;
3297 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3298 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3299 c
->remoteid
= localid
;
3300 c
->type
= CHAN_SOCKDATA
;
3301 c
->v
.v1
.throttling
= 0;
3302 pfd_confirm(c
->u
.pfd
.s
);
3305 if (c
&& c
->closes
) {
3307 * We have a pending close on this channel,
3308 * which we decided on before the server acked
3309 * the channel open. So now we know the
3310 * remoteid, we can close it again.
3312 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3316 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3317 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3318 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3319 struct ssh_channel
*c
;
3321 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3322 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3323 logevent("Forwarded connection refused by server");
3324 pfd_close(c
->u
.pfd
.s
);
3325 del234(ssh_channels
, c
);
3329 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3330 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3331 /* Remote side closes a channel. */
3332 unsigned i
= GET_32BIT(pktin
.body
);
3333 struct ssh_channel
*c
;
3334 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3338 (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3339 if (!(c
->closes
& closetype
))
3340 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
,
3342 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3343 logevent("Forwarded X11 connection terminated");
3344 assert(c
->u
.x11
.s
!= NULL
);
3345 x11_close(c
->u
.x11
.s
);
3348 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3349 logevent("Forwarded port closed");
3350 assert(c
->u
.pfd
.s
!= NULL
);
3351 pfd_close(c
->u
.pfd
.s
);
3354 c
->closes
|= closetype
;
3355 if (c
->closes
== 3) {
3356 del234(ssh_channels
, c
);
3360 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3361 /* Data sent down one of our channels. */
3362 int i
= GET_32BIT(pktin
.body
);
3363 int len
= GET_32BIT(pktin
.body
+ 4);
3364 unsigned char *p
= pktin
.body
+ 8;
3365 struct ssh_channel
*c
;
3366 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3371 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3374 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3377 /* Data for an agent message. Buffer it. */
3379 if (c
->u
.a
.lensofar
< 4) {
3380 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3381 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3385 c
->u
.a
.lensofar
+= l
;
3387 if (c
->u
.a
.lensofar
== 4) {
3389 4 + GET_32BIT(c
->u
.a
.msglen
);
3390 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3391 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3393 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3395 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3397 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3401 c
->u
.a
.lensofar
+= l
;
3403 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3404 void *reply
, *sentreply
;
3406 agent_query(c
->u
.a
.message
,
3407 c
->u
.a
.totallen
, &reply
,
3412 /* Fake SSH_AGENT_FAILURE. */
3413 sentreply
= "\0\0\0\1\5";
3416 send_packet(SSH1_MSG_CHANNEL_DATA
,
3417 PKT_INT
, c
->remoteid
,
3419 PKT_DATA
, sentreply
, replylen
,
3423 sfree(c
->u
.a
.message
);
3424 c
->u
.a
.lensofar
= 0;
3427 bufsize
= 0; /* agent channels never back up */
3430 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3431 c
->v
.v1
.throttling
= 1;
3435 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
3436 /* may be from EXEC_SHELL on some servers */
3437 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3438 /* may be from EXEC_SHELL on some servers
3439 * if no pty is available or in other odd cases. Ignore */
3440 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3442 ssh_exitcode
= GET_32BIT(pktin
.body
);
3443 sprintf(buf
, "Server sent command exit status %d",
3446 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3448 * In case `helpful' firewalls or proxies tack
3449 * extra human-readable text on the end of the
3450 * session which we might mistake for another
3451 * encrypted packet, we close the session once
3452 * we've sent EXIT_CONFIRMATION.
3454 ssh_state
= SSH_STATE_CLOSED
;
3457 bombout(("Strange packet received: type %d", pktin
.type
));
3462 int len
= min(inlen
, 512);
3463 send_packet(SSH1_CMSG_STDIN_DATA
,
3464 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3475 * Utility routine for decoding comma-separated strings in KEXINIT.
3477 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3479 int needlen
= strlen(needle
);
3482 * Is it at the start of the string?
3484 if (haylen
>= needlen
&& /* haystack is long enough */
3485 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3486 (haylen
== needlen
|| haystack
[needlen
] == ',')
3487 /* either , or EOS follows */
3491 * If not, search for the next comma and resume after that.
3492 * If no comma found, terminate.
3494 while (haylen
> 0 && *haystack
!= ',')
3495 haylen
--, haystack
++;
3498 haylen
--, haystack
++; /* skip over comma itself */
3503 * SSH2 key creation method.
3505 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
,
3509 /* First 20 bytes. */
3511 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3513 SHA_Bytes(&s
, H
, 20);
3514 SHA_Bytes(&s
, &chr
, 1);
3515 SHA_Bytes(&s
, sessid
, 20);
3516 SHA_Final(&s
, keyspace
);
3517 /* Next 20 bytes. */
3519 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3521 SHA_Bytes(&s
, H
, 20);
3522 SHA_Bytes(&s
, keyspace
, 20);
3523 SHA_Final(&s
, keyspace
+ 20);
3527 * Handle the SSH2 transport layer.
3529 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
3531 static int i
, j
, len
, nbits
, pbits
, warn
;
3533 static Bignum p
, g
, e
, f
, K
;
3534 static int kex_init_value
, kex_reply_value
;
3535 static const struct ssh_mac
**maclist
;
3537 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
3538 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
3539 static const struct ssh_mac
*csmac_tobe
= NULL
;
3540 static const struct ssh_mac
*scmac_tobe
= NULL
;
3541 static const struct ssh_compress
*cscomp_tobe
= NULL
;
3542 static const struct ssh_compress
*sccomp_tobe
= NULL
;
3543 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3544 static int hostkeylen
, siglen
;
3545 static void *hkey
; /* actual host key */
3546 static unsigned char exchange_hash
[20];
3547 static unsigned char keyspace
[40];
3548 static int n_preferred_ciphers
;
3549 static const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3550 static const struct ssh_compress
*preferred_comp
;
3551 static int cipherstr_started
;
3552 static int first_kex
;
3559 * Set up the preferred ciphers. (NULL => warn below here)
3561 n_preferred_ciphers
= 0;
3562 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3563 switch (cfg
.ssh_cipherlist
[i
]) {
3564 case CIPHER_BLOWFISH
:
3565 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_blowfish
;
3566 n_preferred_ciphers
++;
3569 if (cfg
.ssh2_des_cbc
) {
3570 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_des
;
3571 n_preferred_ciphers
++;
3575 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_3des
;
3576 n_preferred_ciphers
++;
3579 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_aes
;
3580 n_preferred_ciphers
++;
3583 /* Flag for later. Don't bother if it's the last in
3585 if (i
< CIPHER_MAX
- 1) {
3586 preferred_ciphers
[n_preferred_ciphers
] = NULL
;
3587 n_preferred_ciphers
++;
3594 * Set up preferred compression.
3596 if (cfg
.compression
)
3597 preferred_comp
= &ssh_zlib
;
3599 preferred_comp
= &ssh_comp_none
;
3602 * Be prepared to work around the buggy MAC problem.
3604 if (cfg
.buggymac
|| (ssh_remote_bugs
& BUG_SSH2_HMAC
))
3605 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
3607 maclist
= macs
, nmacs
= lenof(macs
);
3611 * Construct and send our key exchange packet.
3613 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
3614 for (i
= 0; i
< 16; i
++)
3615 ssh2_pkt_addbyte((unsigned char) random_byte());
3616 /* List key exchange algorithms. */
3617 ssh2_pkt_addstring_start();
3618 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3619 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
3620 if (i
< lenof(kex_algs
) - 1)
3621 ssh2_pkt_addstring_str(",");
3623 /* List server host key algorithms. */
3624 ssh2_pkt_addstring_start();
3625 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3626 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
3627 if (i
< lenof(hostkey_algs
) - 1)
3628 ssh2_pkt_addstring_str(",");
3630 /* List client->server encryption algorithms. */
3631 ssh2_pkt_addstring_start();
3632 cipherstr_started
= 0;
3633 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3634 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3635 if (!c
) continue; /* warning flag */
3636 for (j
= 0; j
< c
->nciphers
; j
++) {
3637 if (cipherstr_started
)
3638 ssh2_pkt_addstring_str(",");
3639 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3640 cipherstr_started
= 1;
3643 /* List server->client encryption algorithms. */
3644 ssh2_pkt_addstring_start();
3645 cipherstr_started
= 0;
3646 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3647 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3648 if (!c
) continue; /* warning flag */
3649 for (j
= 0; j
< c
->nciphers
; j
++) {
3650 if (cipherstr_started
)
3651 ssh2_pkt_addstring_str(",");
3652 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3653 cipherstr_started
= 1;
3656 /* List client->server MAC algorithms. */
3657 ssh2_pkt_addstring_start();
3658 for (i
= 0; i
< nmacs
; i
++) {
3659 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3661 ssh2_pkt_addstring_str(",");
3663 /* List server->client MAC algorithms. */
3664 ssh2_pkt_addstring_start();
3665 for (i
= 0; i
< nmacs
; i
++) {
3666 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3668 ssh2_pkt_addstring_str(",");
3670 /* List client->server compression algorithms. */
3671 ssh2_pkt_addstring_start();
3672 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3673 const struct ssh_compress
*c
=
3674 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3675 ssh2_pkt_addstring_str(c
->name
);
3676 if (i
< lenof(compressions
))
3677 ssh2_pkt_addstring_str(",");
3679 /* List server->client compression algorithms. */
3680 ssh2_pkt_addstring_start();
3681 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3682 const struct ssh_compress
*c
=
3683 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3684 ssh2_pkt_addstring_str(c
->name
);
3685 if (i
< lenof(compressions
))
3686 ssh2_pkt_addstring_str(",");
3688 /* List client->server languages. Empty list. */
3689 ssh2_pkt_addstring_start();
3690 /* List server->client languages. Empty list. */
3691 ssh2_pkt_addstring_start();
3692 /* First KEX packet does _not_ follow, because we're not that brave. */
3693 ssh2_pkt_addbool(FALSE
);
3695 ssh2_pkt_adduint32(0);
3697 exhash
= exhashbase
;
3698 sha_string(&exhash
, pktout
.data
+ 5, pktout
.length
- 5);
3704 sha_string(&exhash
, pktin
.data
+ 5, pktin
.length
- 5);
3707 * Now examine the other side's KEXINIT to see what we're up
3710 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
3711 bombout(("expected key exchange packet from server"));
3716 cscipher_tobe
= NULL
;
3717 sccipher_tobe
= NULL
;
3722 pktin
.savedpos
+= 16; /* skip garbage cookie */
3723 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
3724 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3725 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3730 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
3731 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3732 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3733 hostkey
= hostkey_algs
[i
];
3737 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
3739 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3740 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3744 for (j
= 0; j
< c
->nciphers
; j
++) {
3745 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3746 cscipher_tobe
= c
->list
[j
];
3751 if (cscipher_tobe
) {
3753 askcipher(cscipher_tobe
->name
, 1);
3757 if (!cscipher_tobe
) {
3758 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3762 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
3764 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3765 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3769 for (j
= 0; j
< c
->nciphers
; j
++) {
3770 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3771 sccipher_tobe
= c
->list
[j
];
3776 if (sccipher_tobe
) {
3778 askcipher(sccipher_tobe
->name
, 2);
3782 if (!sccipher_tobe
) {
3783 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3787 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
3788 for (i
= 0; i
< nmacs
; i
++) {
3789 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3790 csmac_tobe
= maclist
[i
];
3794 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
3795 for (i
= 0; i
< nmacs
; i
++) {
3796 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3797 scmac_tobe
= maclist
[i
];
3801 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
3802 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3803 const struct ssh_compress
*c
=
3804 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3805 if (in_commasep_string(c
->name
, str
, len
)) {
3810 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
3811 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3812 const struct ssh_compress
*c
=
3813 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3814 if (in_commasep_string(c
->name
, str
, len
)) {
3821 * Work out the number of bits of key we will need from the key
3822 * exchange. We start with the maximum key length of either
3828 csbits
= cscipher_tobe
->keylen
;
3829 scbits
= sccipher_tobe
->keylen
;
3830 nbits
= (csbits
> scbits ? csbits
: scbits
);
3832 /* The keys only have 160-bit entropy, since they're based on
3833 * a SHA-1 hash. So cap the key size at 160 bits. */
3838 * If we're doing Diffie-Hellman group exchange, start by
3839 * requesting a group.
3841 if (kex
== &ssh_diffiehellman_gex
) {
3842 logevent("Doing Diffie-Hellman group exchange");
3843 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3845 * Work out how big a DH group we will need to allow that
3848 pbits
= 512 << ((nbits
- 1) / 64);
3849 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
3850 ssh2_pkt_adduint32(pbits
);
3854 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3855 bombout(("expected key exchange group packet from server"));
3858 p
= ssh2_pkt_getmp();
3859 g
= ssh2_pkt_getmp();
3860 dh_setup_group(p
, g
);
3861 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3862 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3864 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3866 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3867 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3870 logevent("Doing Diffie-Hellman key exchange");
3872 * Now generate and send e for Diffie-Hellman.
3874 e
= dh_create_e(nbits
* 2);
3875 ssh2_pkt_init(kex_init_value
);
3880 if (pktin
.type
!= kex_reply_value
) {
3881 bombout(("expected key exchange reply packet from server"));
3884 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
3885 f
= ssh2_pkt_getmp();
3886 ssh2_pkt_getstring(&sigdata
, &siglen
);
3890 sha_string(&exhash
, hostkeydata
, hostkeylen
);
3891 if (kex
== &ssh_diffiehellman_gex
) {
3892 sha_uint32(&exhash
, pbits
);
3893 sha_mpint(&exhash
, p
);
3894 sha_mpint(&exhash
, g
);
3896 sha_mpint(&exhash
, e
);
3897 sha_mpint(&exhash
, f
);
3898 sha_mpint(&exhash
, K
);
3899 SHA_Final(&exhash
, exchange_hash
);
3904 debug(("Exchange hash is:\n"));
3905 dmemdump(exchange_hash
, 20);
3908 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
3910 !hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
3911 bombout(("Server's host key did not match the signature supplied"));
3916 * Authenticate remote host: verify host key. (We've already
3917 * checked the signature of the exchange hash.)
3919 keystr
= hostkey
->fmtkey(hkey
);
3920 fingerprint
= hostkey
->fingerprint(hkey
);
3921 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
3922 keystr
, fingerprint
);
3923 if (first_kex
) { /* don't bother logging this in rekeys */
3924 logevent("Host key fingerprint is:");
3925 logevent(fingerprint
);
3929 hostkey
->freekey(hkey
);
3932 * Send SSH2_MSG_NEWKEYS.
3934 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
3938 * Expect SSH2_MSG_NEWKEYS from server.
3941 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
3942 bombout(("expected new-keys packet from server"));
3947 * Create and initialise session keys.
3949 cscipher
= cscipher_tobe
;
3950 sccipher
= sccipher_tobe
;
3953 cscomp
= cscomp_tobe
;
3954 sccomp
= sccomp_tobe
;
3955 cscomp
->compress_init();
3956 sccomp
->decompress_init();
3958 * Set IVs after keys. Here we use the exchange hash from the
3959 * _first_ key exchange.
3962 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
3963 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
3964 cscipher
->setcskey(keyspace
);
3965 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
3966 sccipher
->setsckey(keyspace
);
3967 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
3968 cscipher
->setcsiv(keyspace
);
3969 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
3970 sccipher
->setsciv(keyspace
);
3971 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
3972 csmac
->setcskey(keyspace
);
3973 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
3974 scmac
->setsckey(keyspace
);
3977 * If this is the first key exchange phase, we must pass the
3978 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
3979 * wants to see it but because it will need time to initialise
3980 * itself before it sees an actual packet. In subsequent key
3981 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
3982 * it would only confuse the layer above.
3990 * Now we're encrypting. Begin returning 1 to the protocol main
3991 * function so that other things can run on top of the
3992 * transport. If we ever see a KEXINIT, we must go back to the
3995 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
3998 logevent("Server initiated key re-exchange");
3999 goto begin_key_exchange
;
4005 * Add data to an SSH2 channel output buffer.
4007 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4010 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4014 * Attempt to send data on an SSH2 channel.
4016 static int ssh2_try_send(struct ssh_channel
*c
)
4018 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4021 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4022 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4023 len
= c
->v
.v2
.remwindow
;
4024 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4025 len
= c
->v
.v2
.remmaxpkt
;
4026 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4027 ssh2_pkt_adduint32(c
->remoteid
);
4028 ssh2_pkt_addstring_start();
4029 ssh2_pkt_addstring_data(data
, len
);
4031 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4032 c
->v
.v2
.remwindow
-= len
;
4036 * After having sent as much data as we can, return the amount
4039 return bufchain_size(&c
->v
.v2
.outbuffer
);
4043 * Potentially enlarge the window on an SSH2 channel.
4045 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4048 * Never send WINDOW_ADJUST for a channel that the remote side
4049 * already thinks it's closed; there's no point, since it won't
4050 * be sending any more data anyway.
4055 if (newwin
> c
->v
.v2
.locwindow
) {
4056 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4057 ssh2_pkt_adduint32(c
->remoteid
);
4058 ssh2_pkt_adduint32(newwin
- c
->v
.v2
.locwindow
);
4060 c
->v
.v2
.locwindow
= newwin
;
4065 * Handle the SSH2 userauth and connection layers.
4067 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
4070 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4072 AUTH_KEYBOARD_INTERACTIVE
4076 AUTH_TYPE_PUBLICKEY
,
4077 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4078 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4080 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4081 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4083 static int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4084 static int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4085 static int kbd_inter_running
;
4086 static int we_are_in
;
4087 static int num_prompts
, curr_prompt
, echo
;
4088 static char username
[100];
4089 static int got_username
;
4090 static char pwprompt
[200];
4091 static char password
[100];
4092 static void *publickey_blob
;
4093 static int publickey_bloblen
;
4098 * Request userauth protocol, and await a response to it.
4100 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
4101 ssh2_pkt_addstring("ssh-userauth");
4103 crWaitUntilV(ispkt
);
4104 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4105 bombout(("Server refused user authentication protocol"));
4110 * We repeat this whole loop, including the username prompt,
4111 * until we manage a successful authentication. If the user
4112 * types the wrong _password_, they are sent back to the
4113 * beginning to try another username. (If they specify a
4114 * username in the config, they are never asked, even if they
4115 * do give a wrong password.)
4117 * I think this best serves the needs of
4119 * - the people who have no configuration, no keys, and just
4120 * want to try repeated (username,password) pairs until they
4121 * type both correctly
4123 * - people who have keys and configuration but occasionally
4124 * need to fall back to passwords
4126 * - people with a key held in Pageant, who might not have
4127 * logged in to a particular machine before; so they want to
4128 * type a username, and then _either_ their key will be
4129 * accepted, _or_ they will type a password. If they mistype
4130 * the username they will want to be able to get back and
4134 got_username
= FALSE
;
4139 if (got_username
&& !cfg
.change_username
) {
4141 * We got a username last time round this loop, and
4142 * with change_username turned off we don't try to get
4145 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4146 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4147 if (!ssh_get_line("login as: ",
4148 username
, sizeof(username
), FALSE
)) {
4150 * get_line failed to get a username.
4153 logevent("No username provided. Abandoning session.");
4154 ssh_state
= SSH_STATE_CLOSED
;
4159 c_write_str("login as: ");
4161 setup_userpass_input(username
, sizeof(username
), 1);
4163 crWaitUntilV(!ispkt
);
4164 ret
= process_userpass_input(in
, inlen
);
4169 c_write_str("\r\n");
4170 username
[strcspn(username
, "\n\r")] = '\0';
4173 strncpy(username
, cfg
.username
, 99);
4174 username
[99] = '\0';
4175 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4176 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
4180 got_username
= TRUE
;
4183 * Send an authentication request using method "none": (a)
4184 * just in case it succeeds, and (b) so that we know what
4185 * authentication methods we can usefully try next.
4187 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4189 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4190 ssh2_pkt_addstring(username
);
4191 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4192 ssh2_pkt_addstring("none"); /* method */
4194 type
= AUTH_TYPE_NONE
;
4198 tried_pubkey_config
= FALSE
;
4199 tried_agent
= FALSE
;
4200 tried_keyb_inter
= FALSE
;
4201 kbd_inter_running
= FALSE
;
4202 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4205 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4206 keytype
= key_type(cfg
.keyfile
);
4207 if (keytype
== SSH_KEYTYPE_SSH2
)
4208 publickey_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4209 &publickey_bloblen
);
4212 logeventf("Unable to use this key file (%s)",
4213 key_type_to_str(keytype
));
4214 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4215 cfg
.keyfile
, key_type_to_str(keytype
));
4216 c_write_str(msgbuf
);
4217 publickey_blob
= NULL
;
4220 publickey_blob
= NULL
;
4224 * Wait for the result of the last authentication request.
4227 crWaitUntilV(ispkt
);
4228 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4232 * Don't show the banner if we're operating in
4233 * non-verbose non-interactive mode. (It's probably
4234 * a script, which means nobody will read the
4235 * banner _anyway_, and moreover the printing of
4236 * the banner will screw up processing on the
4237 * output of (say) plink.)
4239 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4240 ssh2_pkt_getstring(&banner
, &size
);
4242 c_write_untrusted(banner
, size
);
4244 crWaitUntilV(ispkt
);
4246 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4247 logevent("Access granted");
4252 if (kbd_inter_running
&&
4253 pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4255 * This is either a further set-of-prompts packet
4256 * in keyboard-interactive authentication, or it's
4257 * the same one and we came back here with `gotit'
4258 * set. In the former case, we must reset the
4259 * curr_prompt variable.
4263 } else if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4264 bombout(("Strange packet received during authentication: type %d",
4272 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4273 * we can look at the string in it and know what we can
4274 * helpfully try next.
4276 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4279 ssh2_pkt_getstring(&methods
, &methlen
);
4280 kbd_inter_running
= FALSE
;
4281 if (!ssh2_pkt_getbool()) {
4283 * We have received an unequivocal Access
4284 * Denied. This can translate to a variety of
4287 * - if we'd just tried "none" authentication,
4288 * it's not worth printing anything at all
4290 * - if we'd just tried a public key _offer_,
4291 * the message should be "Server refused our
4292 * key" (or no message at all if the key
4293 * came from Pageant)
4295 * - if we'd just tried anything else, the
4296 * message really should be "Access denied".
4298 * Additionally, if we'd just tried password
4299 * authentication, we should break out of this
4300 * whole loop so as to go back to the username
4303 if (type
== AUTH_TYPE_NONE
) {
4305 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4306 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4307 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4308 c_write_str("Server refused our key\r\n");
4309 logevent("Server refused public key");
4310 } else if (type
== AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4311 /* server declined keyboard-interactive; ignore */
4313 c_write_str("Access denied\r\n");
4314 logevent("Access denied");
4315 if (type
== AUTH_TYPE_PASSWORD
) {
4321 c_write_str("Further authentication required\r\n");
4322 logevent("Further authentication required");
4326 in_commasep_string("publickey", methods
, methlen
);
4328 in_commasep_string("password", methods
, methlen
);
4329 can_keyb_inter
= cfg
.try_ki_auth
&&
4330 in_commasep_string("keyboard-interactive", methods
, methlen
);
4334 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4337 * Most password/passphrase prompts will be
4338 * non-echoing, so we set this to 0 by default.
4339 * Exception is that some keyboard-interactive prompts
4340 * can be echoing, in which case we'll set this to 1.
4344 if (!method
&& can_pubkey
&& agent_exists() && !tried_agent
) {
4346 * Attempt public-key authentication using Pageant.
4348 static unsigned char request
[5], *response
, *p
;
4349 static int responselen
;
4350 static int i
, nkeys
;
4351 static int authed
= FALSE
;
4354 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4355 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4359 logevent("Pageant is running. Requesting keys.");
4361 /* Request the keys held by the agent. */
4362 PUT_32BIT(request
, 1);
4363 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4364 agent_query(request
, 5, &r
, &responselen
);
4365 response
= (unsigned char *) r
;
4366 if (response
&& responselen
>= 5 &&
4367 response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4369 nkeys
= GET_32BIT(p
);
4373 sprintf(buf
, "Pageant has %d SSH2 keys", nkeys
);
4376 for (i
= 0; i
< nkeys
; i
++) {
4377 static char *pkblob
, *alg
, *commentp
;
4378 static int pklen
, alglen
, commentlen
;
4379 static int siglen
, retlen
, len
;
4380 static char *q
, *agentreq
, *ret
;
4385 sprintf(buf
, "Trying Pageant key #%d", i
);
4388 pklen
= GET_32BIT(p
);
4390 if (publickey_blob
&&
4391 pklen
== publickey_bloblen
&&
4392 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
4393 logevent("This key matches configured key file");
4394 tried_pubkey_config
= 1;
4398 alglen
= GET_32BIT(pkblob
);
4400 commentlen
= GET_32BIT(p
);
4404 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4405 ssh2_pkt_addstring(username
);
4406 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4407 ssh2_pkt_addstring("publickey"); /* method */
4408 ssh2_pkt_addbool(FALSE
); /* no signature included */
4409 ssh2_pkt_addstring_start();
4410 ssh2_pkt_addstring_data(alg
, alglen
);
4411 ssh2_pkt_addstring_start();
4412 ssh2_pkt_addstring_data(pkblob
, pklen
);
4415 crWaitUntilV(ispkt
);
4416 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4417 logevent("Key refused");
4421 if (flags
& FLAG_VERBOSE
) {
4423 ("Authenticating with public key \"");
4424 c_write(commentp
, commentlen
);
4425 c_write_str("\" from agent\r\n");
4429 * Server is willing to accept the key.
4430 * Construct a SIGN_REQUEST.
4432 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4433 ssh2_pkt_addstring(username
);
4434 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4435 ssh2_pkt_addstring("publickey"); /* method */
4436 ssh2_pkt_addbool(TRUE
);
4437 ssh2_pkt_addstring_start();
4438 ssh2_pkt_addstring_data(alg
, alglen
);
4439 ssh2_pkt_addstring_start();
4440 ssh2_pkt_addstring_data(pkblob
, pklen
);
4442 siglen
= pktout
.length
- 5 + 4 + 20;
4443 len
= 1; /* message type */
4444 len
+= 4 + pklen
; /* key blob */
4445 len
+= 4 + siglen
; /* data to sign */
4446 len
+= 4; /* flags */
4447 agentreq
= smalloc(4 + len
);
4448 PUT_32BIT(agentreq
, len
);
4450 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4451 PUT_32BIT(q
, pklen
);
4453 memcpy(q
, pkblob
, pklen
);
4455 PUT_32BIT(q
, siglen
);
4457 /* Now the data to be signed... */
4460 memcpy(q
, ssh2_session_id
, 20);
4462 memcpy(q
, pktout
.data
+ 5, pktout
.length
- 5);
4463 q
+= pktout
.length
- 5;
4464 /* And finally the (zero) flags word. */
4466 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
4470 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4471 logevent("Sending Pageant's response");
4472 ssh2_add_sigblob(pkblob
, pklen
,
4473 ret
+ 9, GET_32BIT(ret
+ 5));
4479 ("Pageant failed to answer challenge");
4489 if (!method
&& can_pubkey
&& publickey_blob
4490 && !tried_pubkey_config
) {
4491 unsigned char *pub_blob
;
4492 char *algorithm
, *comment
;
4495 tried_pubkey_config
= TRUE
;
4497 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4498 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4501 * Try the public key supplied in the configuration.
4503 * First, offer the public blob to see if the server is
4504 * willing to accept it.
4506 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4509 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4510 ssh2_pkt_addstring(username
);
4511 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4512 ssh2_pkt_addstring("publickey"); /* method */
4513 ssh2_pkt_addbool(FALSE
); /* no signature included */
4514 ssh2_pkt_addstring(algorithm
);
4515 ssh2_pkt_addstring_start();
4516 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
4518 logevent("Offered public key"); /* FIXME */
4520 crWaitUntilV(ispkt
);
4521 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4523 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4524 continue; /* key refused; give up on it */
4527 logevent("Offer of public key accepted");
4529 * Actually attempt a serious authentication using
4532 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4534 "Passphrase for key \"%.100s\": ",
4540 c_write_str("Authenticating with public key \"");
4541 c_write_str(comment
);
4542 c_write_str("\"\r\n");
4543 method
= AUTH_PUBLICKEY_FILE
;
4547 if (!method
&& can_keyb_inter
&& !tried_keyb_inter
) {
4548 method
= AUTH_KEYBOARD_INTERACTIVE
;
4549 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4550 tried_keyb_inter
= TRUE
;
4552 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4553 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4555 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4556 ssh2_pkt_addstring(username
);
4557 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4558 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4559 ssh2_pkt_addstring(""); /* lang */
4560 ssh2_pkt_addstring("");
4563 crWaitUntilV(ispkt
);
4564 if (pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4565 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4567 logevent("Keyboard-interactive authentication refused");
4568 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4572 kbd_inter_running
= TRUE
;
4576 if (kbd_inter_running
) {
4577 method
= AUTH_KEYBOARD_INTERACTIVE
;
4578 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4579 tried_keyb_inter
= TRUE
;
4581 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4582 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4584 if (curr_prompt
== 0) {
4586 * We've got a fresh USERAUTH_INFO_REQUEST.
4587 * Display header data, and start going through
4590 char *name
, *inst
, *lang
;
4591 int name_len
, inst_len
, lang_len
;
4593 ssh2_pkt_getstring(&name
, &name_len
);
4594 ssh2_pkt_getstring(&inst
, &inst_len
);
4595 ssh2_pkt_getstring(&lang
, &lang_len
);
4597 c_write_untrusted(name
, name_len
);
4598 c_write_str("\r\n");
4601 c_write_untrusted(inst
, inst_len
);
4602 c_write_str("\r\n");
4604 num_prompts
= ssh2_pkt_getuint32();
4608 * If there are prompts remaining in the packet,
4609 * display one and get a response.
4611 if (curr_prompt
< num_prompts
) {
4615 ssh2_pkt_getstring(&prompt
, &prompt_len
);
4616 if (prompt_len
> 0) {
4617 strncpy(pwprompt
, prompt
, sizeof(pwprompt
));
4618 pwprompt
[prompt_len
< sizeof(pwprompt
) ?
4619 prompt_len
: sizeof(pwprompt
)-1] = '\0';
4622 "<server failed to send prompt>: ");
4624 echo
= ssh2_pkt_getbool();
4630 if (!method
&& can_passwd
) {
4631 method
= AUTH_PASSWORD
;
4632 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4633 ssh_pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4634 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
,
4641 if (!ssh_get_line(pwprompt
, password
,
4642 sizeof(password
), TRUE
)) {
4644 * get_line failed to get a password (for
4645 * example because one was supplied on the
4646 * command line which has already failed to
4649 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4650 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4652 ("No more passwords available to try");
4653 ssh2_pkt_addstring("en"); /* language tag */
4655 logevent("Unable to authenticate");
4656 connection_fatal("Unable to authenticate");
4657 ssh_state
= SSH_STATE_CLOSED
;
4662 c_write_untrusted(pwprompt
, strlen(pwprompt
));
4665 setup_userpass_input(password
, sizeof(password
), echo
);
4667 crWaitUntilV(!ispkt
);
4668 ret
= process_userpass_input(in
, inlen
);
4672 c_write_str("\r\n");
4676 if (method
== AUTH_PUBLICKEY_FILE
) {
4678 * We have our passphrase. Now try the actual authentication.
4680 struct ssh2_userkey
*key
;
4682 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
4683 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4684 if (key
== SSH2_WRONG_PASSPHRASE
) {
4685 c_write_str("Wrong passphrase\r\n");
4686 tried_pubkey_config
= FALSE
;
4688 c_write_str("Unable to load private key\r\n");
4689 tried_pubkey_config
= TRUE
;
4691 /* Send a spurious AUTH_NONE to return to the top. */
4692 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4693 ssh2_pkt_addstring(username
);
4694 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4695 ssh2_pkt_addstring("none"); /* method */
4697 type
= AUTH_TYPE_NONE
;
4699 unsigned char *pkblob
, *sigblob
, *sigdata
;
4700 int pkblob_len
, sigblob_len
, sigdata_len
;
4703 * We have loaded the private key and the server
4704 * has announced that it's willing to accept it.
4705 * Hallelujah. Generate a signature and send it.
4707 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4708 ssh2_pkt_addstring(username
);
4709 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4710 ssh2_pkt_addstring("publickey"); /* method */
4711 ssh2_pkt_addbool(TRUE
);
4712 ssh2_pkt_addstring(key
->alg
->name
);
4713 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4714 ssh2_pkt_addstring_start();
4715 ssh2_pkt_addstring_data(pkblob
, pkblob_len
);
4718 * The data to be signed is:
4722 * followed by everything so far placed in the
4725 sigdata_len
= pktout
.length
- 5 + 4 + 20;
4726 sigdata
= smalloc(sigdata_len
);
4727 PUT_32BIT(sigdata
, 20);
4728 memcpy(sigdata
+ 4, ssh2_session_id
, 20);
4729 memcpy(sigdata
+ 24, pktout
.data
+ 5,
4731 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4732 sigdata_len
, &sigblob_len
);
4733 ssh2_add_sigblob(pkblob
, pkblob_len
,
4734 sigblob
, sigblob_len
);
4740 type
= AUTH_TYPE_PUBLICKEY
;
4742 } else if (method
== AUTH_PASSWORD
) {
4744 * We send the password packet lumped tightly together with
4745 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4746 * string long enough to make the total length of the two
4747 * packets constant. This should ensure that a passive
4748 * listener doing traffic analyis can't work out the length
4751 * For this to work, we need an assumption about the
4752 * maximum length of the password packet. I think 256 is
4753 * pretty conservative. Anyone using a password longer than
4754 * that probably doesn't have much to worry about from
4755 * people who find out how long their password is!
4757 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4758 ssh2_pkt_addstring(username
);
4759 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4760 ssh2_pkt_addstring("password");
4761 ssh2_pkt_addbool(FALSE
);
4762 ssh2_pkt_addstring(password
);
4765 * We'll include a string that's an exact multiple of the
4766 * cipher block size. If the cipher is NULL for some
4767 * reason, we don't do this trick at all because we gain
4773 stringlen
= (256 - deferred_len
);
4774 stringlen
+= cscipher
->blksize
- 1;
4775 stringlen
-= (stringlen
% cscipher
->blksize
);
4778 * Temporarily disable actual compression,
4779 * so we can guarantee to get this string
4780 * exactly the length we want it. The
4781 * compression-disabling routine should
4782 * return an integer indicating how many
4783 * bytes we should adjust our string length
4786 stringlen
-= cscomp
->disable_compression();
4788 ssh2_pkt_init(SSH2_MSG_IGNORE
);
4789 ssh2_pkt_addstring_start();
4790 for (i
= 0; i
< stringlen
; i
++) {
4791 char c
= (char) random_byte();
4792 ssh2_pkt_addstring_data(&c
, 1);
4796 ssh_pkt_defersend();
4797 logevent("Sent password");
4798 type
= AUTH_TYPE_PASSWORD
;
4799 } else if (method
== AUTH_KEYBOARD_INTERACTIVE
) {
4800 if (curr_prompt
== 0) {
4801 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4802 ssh2_pkt_adduint32(num_prompts
);
4804 if (need_pw
) { /* only add pw if we just got one! */
4805 ssh2_pkt_addstring(password
);
4806 memset(password
, 0, sizeof(password
));
4809 if (curr_prompt
>= num_prompts
) {
4813 * If there are prompts remaining, we set
4814 * `gotit' so that we won't attempt to get
4815 * another packet. Then we go back round the
4816 * loop and will end up retrieving another
4817 * prompt out of the existing packet. Funky or
4822 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4825 ("No supported authentication methods left to try!\r\n");
4827 ("No supported authentications offered. Disconnecting");
4828 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4829 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4831 ("No supported authentication methods available");
4832 ssh2_pkt_addstring("en"); /* language tag */
4834 ssh_state
= SSH_STATE_CLOSED
;
4838 } while (!we_are_in
);
4841 * Now we're authenticated for the connection protocol. The
4842 * connection protocol will automatically have started at this
4843 * point; there's no need to send SERVICE_REQUEST.
4847 * So now create a channel with a session in it.
4849 ssh_channels
= newtree234(ssh_channelcmp
);
4850 mainchan
= smalloc(sizeof(struct ssh_channel
));
4851 mainchan
->localid
= alloc_channel_id();
4852 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
4853 ssh2_pkt_addstring("session");
4854 ssh2_pkt_adduint32(mainchan
->localid
);
4855 mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
4856 ssh2_pkt_adduint32(mainchan
->v
.v2
.locwindow
); /* our window size */
4857 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
4859 crWaitUntilV(ispkt
);
4860 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
4861 bombout(("Server refused to open a session"));
4863 /* FIXME: error data comes back in FAILURE packet */
4865 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
4866 bombout(("Server's channel confirmation cited wrong channel"));
4869 mainchan
->remoteid
= ssh2_pkt_getuint32();
4870 mainchan
->type
= CHAN_MAINSESSION
;
4871 mainchan
->closes
= 0;
4872 mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
4873 mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
4874 bufchain_init(&mainchan
->v
.v2
.outbuffer
);
4875 add234(ssh_channels
, mainchan
);
4876 logevent("Opened channel for session");
4879 * Potentially enable X11 forwarding.
4881 if (cfg
.x11_forward
) {
4882 char proto
[20], data
[64];
4883 logevent("Requesting X11 forwarding");
4884 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
4885 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
4886 ssh2_pkt_adduint32(mainchan
->remoteid
);
4887 ssh2_pkt_addstring("x11-req");
4888 ssh2_pkt_addbool(1); /* want reply */
4889 ssh2_pkt_addbool(0); /* many connections */
4890 ssh2_pkt_addstring(proto
);
4891 ssh2_pkt_addstring(data
);
4892 ssh2_pkt_adduint32(0); /* screen number */
4896 crWaitUntilV(ispkt
);
4897 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
4898 unsigned i
= ssh2_pkt_getuint32();
4899 struct ssh_channel
*c
;
4900 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
4902 continue; /* nonexistent channel */
4903 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
4905 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4907 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
4908 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
4909 bombout(("Unexpected response to X11 forwarding request:"
4910 " packet type %d", pktin
.type
));
4913 logevent("X11 forwarding refused");
4915 logevent("X11 forwarding enabled");
4916 ssh_X11_fwd_enabled
= TRUE
;
4921 * Enable port forwardings.
4924 static char *e
; /* preserve across crReturn */
4927 int sport
,dport
,sserv
,dserv
;
4928 char sports
[256], dports
[256], host
[256];
4932 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4933 /* Add port forwardings. */
4938 while (*e
&& *e
!= '\t')
4944 while (*e
&& *e
!= ':')
4954 dport
= atoi(dports
);
4958 se
= getservbyname(dports
, NULL
);
4960 dport
= ntohs(se
->s_port
);
4963 "Service lookup failed for destination port \"%s\"",
4968 sport
= atoi(sports
);
4972 se
= getservbyname(sports
, NULL
);
4974 sport
= ntohs(se
->s_port
);
4977 "Service lookup failed for source port \"%s\"",
4982 if (sport
&& dport
) {
4984 pfd_addforward(host
, dport
, sport
);
4985 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
4986 " %s:%.*s%.*s%d%.*s",
4987 sserv ?
strlen(sports
) : 0, sports
,
4988 sserv
, "(", sport
, sserv
, ")",
4990 dserv ?
strlen(dports
) : 0, dports
,
4991 dserv
, "(", dport
, dserv
, ")");
4994 struct ssh_rportfwd
*pf
;
4995 pf
= smalloc(sizeof(*pf
));
4996 strcpy(pf
->dhost
, host
);
4999 if (add234(ssh_rportfwds
, pf
) != pf
) {
5001 "Duplicate remote port forwarding to %s:%d",
5006 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
5007 " forward to %s:%.*s%.*s%d%.*s",
5008 sserv ?
strlen(sports
) : 0, sports
,
5009 sserv
, "(", sport
, sserv
, ")",
5011 dserv ?
strlen(dports
) : 0, dports
,
5012 dserv
, "(", dport
, dserv
, ")");
5014 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
5015 ssh2_pkt_addstring("tcpip-forward");
5016 ssh2_pkt_addbool(1);/* want reply */
5017 if (cfg
.rport_acceptall
)
5018 ssh2_pkt_addstring("0.0.0.0");
5020 ssh2_pkt_addstring("127.0.0.1");
5021 ssh2_pkt_adduint32(sport
);
5025 crWaitUntilV(ispkt
);
5026 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5027 unsigned i
= ssh2_pkt_getuint32();
5028 struct ssh_channel
*c
;
5029 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5031 continue;/* nonexistent channel */
5032 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5034 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5036 if (pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5037 if (pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5038 bombout(("Unexpected response to port "
5039 "forwarding request: packet type %d",
5043 logevent("Server refused this port forwarding");
5045 logevent("Remote port forwarding enabled");
5054 * Potentially enable agent forwarding.
5056 if (cfg
.agentfwd
&& agent_exists()) {
5057 logevent("Requesting OpenSSH-style agent forwarding");
5058 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5059 ssh2_pkt_adduint32(mainchan
->remoteid
);
5060 ssh2_pkt_addstring("auth-agent-req@openssh.com");
5061 ssh2_pkt_addbool(1); /* want reply */
5065 crWaitUntilV(ispkt
);
5066 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5067 unsigned i
= ssh2_pkt_getuint32();
5068 struct ssh_channel
*c
;
5069 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5071 continue; /* nonexistent channel */
5072 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5074 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5076 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5077 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5078 bombout(("Unexpected response to agent forwarding request:"
5079 " packet type %d", pktin
.type
));
5082 logevent("Agent forwarding refused");
5084 logevent("Agent forwarding enabled");
5085 ssh_agentfwd_enabled
= TRUE
;
5090 * Now allocate a pty for the session.
5093 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5094 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5095 ssh2_pkt_addstring("pty-req");
5096 ssh2_pkt_addbool(1); /* want reply */
5097 ssh2_pkt_addstring(cfg
.termtype
);
5098 ssh2_pkt_adduint32(cols
);
5099 ssh2_pkt_adduint32(rows
);
5100 ssh2_pkt_adduint32(0); /* pixel width */
5101 ssh2_pkt_adduint32(0); /* pixel height */
5102 ssh2_pkt_addstring_start();
5103 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
5105 ssh_state
= SSH_STATE_INTERMED
;
5108 crWaitUntilV(ispkt
);
5109 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5110 unsigned i
= ssh2_pkt_getuint32();
5111 struct ssh_channel
*c
;
5112 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5114 continue; /* nonexistent channel */
5115 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5117 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5119 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5120 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5121 bombout(("Unexpected response to pty request:"
5122 " packet type %d", pktin
.type
));
5125 c_write_str("Server refused to allocate pty\r\n");
5126 ssh_editing
= ssh_echoing
= 1;
5128 logevent("Allocated pty");
5131 ssh_editing
= ssh_echoing
= 1;
5135 * Start a shell or a remote command. We may have to attempt
5136 * this twice if the config data has provided a second choice
5143 if (ssh_fallback_cmd
) {
5144 subsys
= cfg
.ssh_subsys2
;
5145 cmd
= cfg
.remote_cmd_ptr2
;
5147 subsys
= cfg
.ssh_subsys
;
5148 cmd
= cfg
.remote_cmd_ptr
;
5151 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5152 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5154 ssh2_pkt_addstring("subsystem");
5155 ssh2_pkt_addbool(1); /* want reply */
5156 ssh2_pkt_addstring(cmd
);
5158 ssh2_pkt_addstring("exec");
5159 ssh2_pkt_addbool(1); /* want reply */
5160 ssh2_pkt_addstring(cmd
);
5162 ssh2_pkt_addstring("shell");
5163 ssh2_pkt_addbool(1); /* want reply */
5167 crWaitUntilV(ispkt
);
5168 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5169 unsigned i
= ssh2_pkt_getuint32();
5170 struct ssh_channel
*c
;
5171 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5173 continue; /* nonexistent channel */
5174 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5176 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5177 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5178 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5179 bombout(("Unexpected response to shell/command request:"
5180 " packet type %d", pktin
.type
));
5184 * We failed to start the command. If this is the
5185 * fallback command, we really are finished; if it's
5186 * not, and if the fallback command exists, try falling
5187 * back to it before complaining.
5189 if (!ssh_fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5190 logevent("Primary command failed; attempting fallback");
5191 ssh_fallback_cmd
= TRUE
;
5194 bombout(("Server refused to start a shell/command"));
5197 logevent("Started a shell/command");
5202 ssh_state
= SSH_STATE_SESSION
;
5206 ssh_special(TS_EOF
);
5211 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
5214 static int try_send
;
5218 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5219 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5222 unsigned i
= ssh2_pkt_getuint32();
5223 struct ssh_channel
*c
;
5224 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5226 continue; /* nonexistent channel */
5227 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5228 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
5229 continue; /* extended but not stderr */
5230 ssh2_pkt_getstring(&data
, &length
);
5233 c
->v
.v2
.locwindow
-= length
;
5235 case CHAN_MAINSESSION
:
5237 from_backend(pktin
.type
==
5238 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5242 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5245 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5248 while (length
> 0) {
5249 if (c
->u
.a
.lensofar
< 4) {
5250 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5251 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5255 c
->u
.a
.lensofar
+= l
;
5257 if (c
->u
.a
.lensofar
== 4) {
5259 4 + GET_32BIT(c
->u
.a
.msglen
);
5260 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5261 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5263 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5265 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5267 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5271 c
->u
.a
.lensofar
+= l
;
5273 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5274 void *reply
, *sentreply
;
5276 agent_query(c
->u
.a
.message
,
5277 c
->u
.a
.totallen
, &reply
,
5282 /* Fake SSH_AGENT_FAILURE. */
5283 sentreply
= "\0\0\0\1\5";
5286 ssh2_add_channel_data(c
, sentreply
,
5291 sfree(c
->u
.a
.message
);
5292 c
->u
.a
.lensofar
= 0;
5299 * If we are not buffering too much data,
5300 * enlarge the window again at the remote side.
5302 if (bufsize
< OUR_V2_WINSIZE
)
5303 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5305 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
5306 ssh_state
= SSH_STATE_CLOSED
;
5307 logevent("Received disconnect message");
5309 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5310 unsigned i
= ssh2_pkt_getuint32();
5311 struct ssh_channel
*c
;
5313 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5315 continue; /* nonexistent channel */
5317 if (c
->type
== CHAN_X11
) {
5319 * Remote EOF on an X11 channel means we should
5320 * wrap up and close the channel ourselves.
5322 x11_close(c
->u
.x11
.s
);
5324 } else if (c
->type
== CHAN_AGENT
) {
5326 } else if (c
->type
== CHAN_SOCKDATA
) {
5327 pfd_close(c
->u
.pfd
.s
);
5330 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5331 unsigned i
= ssh2_pkt_getuint32();
5332 struct ssh_channel
*c
;
5334 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5336 continue; /* nonexistent channel */
5337 /* Do pre-close processing on the channel. */
5339 case CHAN_MAINSESSION
:
5340 break; /* nothing to see here, move along */
5342 if (c
->u
.x11
.s
!= NULL
)
5343 x11_close(c
->u
.x11
.s
);
5350 if (c
->u
.pfd
.s
!= NULL
)
5351 pfd_close(c
->u
.pfd
.s
);
5355 if (c
->closes
== 0) {
5356 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5357 ssh2_pkt_adduint32(c
->remoteid
);
5360 del234(ssh_channels
, c
);
5361 bufchain_clear(&c
->v
.v2
.outbuffer
);
5365 * See if that was the last channel left open.
5367 if (count234(ssh_channels
) == 0) {
5370 * We used to send SSH_MSG_DISCONNECT here,
5371 * because I'd believed that _every_ conforming
5372 * SSH2 connection had to end with a disconnect
5373 * being sent by at least one side; apparently
5374 * I was wrong and it's perfectly OK to
5375 * unceremoniously slam the connection shut
5376 * when you're done, and indeed OpenSSH feels
5377 * this is more polite than sending a
5378 * DISCONNECT. So now we don't.
5380 logevent("All channels closed. Disconnecting");
5381 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5382 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5383 ssh2_pkt_addstring("All open channels closed");
5384 ssh2_pkt_addstring("en"); /* language tag */
5387 ssh_state
= SSH_STATE_CLOSED
;
5390 continue; /* remote sends close; ignore (FIXME) */
5391 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5392 unsigned i
= ssh2_pkt_getuint32();
5393 struct ssh_channel
*c
;
5394 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5396 continue; /* nonexistent channel */
5397 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5399 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5400 unsigned i
= ssh2_pkt_getuint32();
5401 struct ssh_channel
*c
;
5402 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5404 continue; /* nonexistent channel */
5405 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5406 continue; /* dunno why they're confirming this */
5407 c
->remoteid
= ssh2_pkt_getuint32();
5408 c
->type
= CHAN_SOCKDATA
;
5409 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
5410 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
5412 pfd_confirm(c
->u
.pfd
.s
);
5415 * We have a pending close on this channel,
5416 * which we decided on before the server acked
5417 * the channel open. So now we know the
5418 * remoteid, we can close it again.
5420 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5421 ssh2_pkt_adduint32(c
->remoteid
);
5424 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5425 unsigned i
= ssh2_pkt_getuint32();
5426 struct ssh_channel
*c
;
5427 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5429 continue; /* nonexistent channel */
5430 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5431 continue; /* dunno why they're failing this */
5433 logevent("Forwarded connection refused by server");
5435 pfd_close(c
->u
.pfd
.s
);
5437 del234(ssh_channels
, c
);
5439 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5442 int typelen
, want_reply
;
5443 struct ssh_channel
*c
;
5445 localid
= ssh2_pkt_getuint32();
5446 ssh2_pkt_getstring(&type
, &typelen
);
5447 want_reply
= ssh2_pkt_getbool();
5450 * First, check that the channel exists. Otherwise,
5451 * we can instantly disconnect with a rude message.
5453 c
= find234(ssh_channels
, &localid
, ssh_channelfind
);
5456 sprintf(buf
, "Received channel request for nonexistent"
5457 " channel %d", localid
);
5459 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5460 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5461 ssh2_pkt_addstring(buf
);
5462 ssh2_pkt_addstring("en"); /* language tag */
5464 connection_fatal("%s", buf
);
5465 ssh_state
= SSH_STATE_CLOSED
;
5470 * Having got the channel number, we now look at
5471 * the request type string to see if it's something
5474 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5476 /* We recognise "exit-status" on the primary channel. */
5478 ssh_exitcode
= ssh2_pkt_getuint32();
5479 sprintf(buf
, "Server sent command exit status %d",
5483 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS
);
5484 ssh2_pkt_adduint32(c
->remoteid
);
5489 * This is a channel request we don't know
5490 * about, so we now either ignore the request
5491 * or respond with CHANNEL_FAILURE, depending
5495 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE
);
5496 ssh2_pkt_adduint32(c
->remoteid
);
5500 } else if (pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5502 int typelen
, want_reply
;
5504 ssh2_pkt_getstring(&type
, &typelen
);
5505 want_reply
= ssh2_pkt_getbool();
5508 * We currently don't support any global requests
5509 * at all, so we either ignore the request or
5510 * respond with REQUEST_FAILURE, depending on
5514 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5517 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5521 struct ssh_channel
*c
;
5522 unsigned remid
, winsize
, pktsize
;
5523 ssh2_pkt_getstring(&type
, &typelen
);
5524 c
= smalloc(sizeof(struct ssh_channel
));
5526 remid
= ssh2_pkt_getuint32();
5527 winsize
= ssh2_pkt_getuint32();
5528 pktsize
= ssh2_pkt_getuint32();
5530 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5531 if (!ssh_X11_fwd_enabled
)
5532 error
= "X11 forwarding is not enabled";
5533 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5535 error
= "Unable to open an X11 connection";
5539 } else if (typelen
== 15 &&
5540 !memcmp(type
, "forwarded-tcpip", 15)) {
5541 struct ssh_rportfwd pf
, *realpf
;
5544 ssh2_pkt_getstring(&dummy
, &dummylen
);/* skip address */
5545 pf
.sport
= ssh2_pkt_getuint32();
5546 realpf
= find234(ssh_rportfwds
, &pf
, NULL
);
5547 if (realpf
== NULL
) {
5548 error
= "Remote port is not recognised";
5550 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5553 sprintf(buf
, "Received remote port open request for %s:%d",
5554 realpf
->dhost
, realpf
->dport
);
5557 sprintf(buf
, "Port open failed: %s", e
);
5559 error
= "Port open failed";
5561 logevent("Forwarded port opened successfully");
5562 c
->type
= CHAN_SOCKDATA
;
5565 } else if (typelen
== 22 &&
5566 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5567 if (!ssh_agentfwd_enabled
)
5568 error
= "Agent forwarding is not enabled";
5570 c
->type
= CHAN_AGENT
; /* identify channel type */
5571 c
->u
.a
.lensofar
= 0;
5574 error
= "Unsupported channel type requested";
5577 c
->remoteid
= remid
;
5579 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5580 ssh2_pkt_adduint32(c
->remoteid
);
5581 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
5582 ssh2_pkt_addstring(error
);
5583 ssh2_pkt_addstring("en"); /* language tag */
5587 c
->localid
= alloc_channel_id();
5589 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5590 c
->v
.v2
.remwindow
= winsize
;
5591 c
->v
.v2
.remmaxpkt
= pktsize
;
5592 bufchain_init(&c
->v
.v2
.outbuffer
);
5593 add234(ssh_channels
, c
);
5594 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5595 ssh2_pkt_adduint32(c
->remoteid
);
5596 ssh2_pkt_adduint32(c
->localid
);
5597 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);
5598 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5602 bombout(("Strange packet received: type %d", pktin
.type
));
5607 * We have spare data. Add it to the channel buffer.
5609 ssh2_add_channel_data(mainchan
, in
, inlen
);
5614 struct ssh_channel
*c
;
5616 * Try to send data on all channels if we can.
5618 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
5619 int bufsize
= ssh2_try_send(c
);
5622 case CHAN_MAINSESSION
:
5623 /* stdin need not receive an unthrottle
5624 * notification since it will be polled */
5627 x11_unthrottle(c
->u
.x11
.s
);
5630 /* agent sockets are request/response and need no
5631 * buffer management */
5634 pfd_unthrottle(c
->u
.pfd
.s
);
5646 * Handle the top-level SSH2 protocol.
5648 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
5650 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
5652 do_ssh2_authconn(in
, inlen
, ispkt
);
5656 * Called to set up the connection.
5658 * Returns an error message, or NULL on success.
5660 static char *ssh_init(char *host
, int port
, char **realhost
, int nodelay
)
5665 if (crypto_startup() == 0)
5666 return "Microsoft high encryption pack not installed!";
5672 ssh1_throttle_count
= 0;
5673 ssh_overall_bufsize
= 0;
5674 ssh_fallback_cmd
= 0;
5676 p
= connect_to_host(host
, port
, realhost
, nodelay
);
5684 * Called to send data down the Telnet connection.
5686 static int ssh_send(char *buf
, int len
)
5688 if (s
== NULL
|| ssh_protocol
== NULL
)
5691 ssh_protocol(buf
, len
, 0);
5693 return ssh_sendbuffer();
5697 * Called to query the current amount of buffered stdin data.
5699 static int ssh_sendbuffer(void)
5703 if (s
== NULL
|| ssh_protocol
== NULL
)
5707 * If the SSH socket itself has backed up, add the total backup
5708 * size on that to any individual buffer on the stdin channel.
5711 if (ssh_throttled_all
)
5712 override_value
= ssh_overall_bufsize
;
5714 if (ssh_version
== 1) {
5715 return override_value
;
5716 } else if (ssh_version
== 2) {
5717 if (!mainchan
|| mainchan
->closes
> 0)
5718 return override_value
;
5720 return override_value
+ bufchain_size(&mainchan
->v
.v2
.outbuffer
);
5727 * Called to set the size of the window from SSH's POV.
5729 static void ssh_size(void)
5731 switch (ssh_state
) {
5732 case SSH_STATE_BEFORE_SIZE
:
5733 case SSH_STATE_PREPACKET
:
5734 case SSH_STATE_CLOSED
:
5735 break; /* do nothing */
5736 case SSH_STATE_INTERMED
:
5737 size_needed
= TRUE
; /* buffer for later */
5739 case SSH_STATE_SESSION
:
5741 if (ssh_version
== 1) {
5742 send_packet(SSH1_CMSG_WINDOW_SIZE
,
5743 PKT_INT
, rows
, PKT_INT
, cols
,
5744 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5746 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5747 ssh2_pkt_adduint32(mainchan
->remoteid
);
5748 ssh2_pkt_addstring("window-change");
5749 ssh2_pkt_addbool(0);
5750 ssh2_pkt_adduint32(cols
);
5751 ssh2_pkt_adduint32(rows
);
5752 ssh2_pkt_adduint32(0);
5753 ssh2_pkt_adduint32(0);
5762 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5763 * can send an EOF and collect resulting output (e.g. `plink
5766 static void ssh_special(Telnet_Special code
)
5768 if (code
== TS_EOF
) {
5769 if (ssh_state
!= SSH_STATE_SESSION
) {
5771 * Buffer the EOF in case we are pre-SESSION, so we can
5772 * send it as soon as we reach SESSION.
5778 if (ssh_version
== 1) {
5779 send_packet(SSH1_CMSG_EOF
, PKT_END
);
5781 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
5782 ssh2_pkt_adduint32(mainchan
->remoteid
);
5785 logevent("Sent EOF message");
5786 } else if (code
== TS_PING
) {
5787 if (ssh_state
== SSH_STATE_CLOSED
5788 || ssh_state
== SSH_STATE_PREPACKET
) return;
5789 if (ssh_version
== 1) {
5790 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
5792 ssh2_pkt_init(SSH2_MSG_IGNORE
);
5793 ssh2_pkt_addstring_start();
5801 void *new_sock_channel(Socket s
)
5803 struct ssh_channel
*c
;
5804 c
= smalloc(sizeof(struct ssh_channel
));
5807 c
->remoteid
= -1; /* to be set when open confirmed */
5808 c
->localid
= alloc_channel_id();
5810 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
5812 bufchain_init(&c
->v
.v2
.outbuffer
);
5813 add234(ssh_channels
, c
);
5819 * This is called when stdout/stderr (the entity to which
5820 * from_backend sends data) manages to clear some backlog.
5822 void ssh_unthrottle(int bufsize
)
5824 if (ssh_version
== 1) {
5825 if (ssh1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
5826 ssh1_stdout_throttling
= 0;
5830 if (mainchan
&& mainchan
->closes
== 0)
5831 ssh2_set_window(mainchan
, OUR_V2_WINSIZE
- bufsize
);
5835 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
5837 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
5840 sprintf(buf
, "Opening forwarded connection to %.512s:%d", hostname
, port
);
5843 if (ssh_version
== 1) {
5844 send_packet(SSH1_MSG_PORT_OPEN
,
5845 PKT_INT
, c
->localid
,
5848 //PKT_STR, <org:orgport>,
5851 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
5852 ssh2_pkt_addstring("direct-tcpip");
5853 ssh2_pkt_adduint32(c
->localid
);
5854 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5855 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);/* our window size */
5856 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5857 ssh2_pkt_addstring(hostname
);
5858 ssh2_pkt_adduint32(port
);
5860 * We make up values for the originator data; partly it's
5861 * too much hassle to keep track, and partly I'm not
5862 * convinced the server should be told details like that
5863 * about my local network configuration.
5865 ssh2_pkt_addstring("client-side-connection");
5866 ssh2_pkt_adduint32(0);
5872 static Socket
ssh_socket(void)
5877 static int ssh_sendok(void)
5882 static int ssh_ldisc(int option
)
5884 if (option
== LD_ECHO
)
5886 if (option
== LD_EDIT
)
5891 static int ssh_return_exitcode(void)
5893 return ssh_exitcode
;
5896 Backend ssh_backend
= {
5903 ssh_return_exitcode
,