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
186 static int ssh_pkt_ctx
= 0;
188 #define translate(x) if (type == x) return #x
189 #define translatec(x,ctx) if (type == x && (ssh_pkt_ctx & ctx)) return #x
190 char *ssh1_pkt_type(int type
)
192 translate(SSH1_MSG_DISCONNECT
);
193 translate(SSH1_SMSG_PUBLIC_KEY
);
194 translate(SSH1_CMSG_SESSION_KEY
);
195 translate(SSH1_CMSG_USER
);
196 translate(SSH1_CMSG_AUTH_RSA
);
197 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
198 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
199 translate(SSH1_CMSG_AUTH_PASSWORD
);
200 translate(SSH1_CMSG_REQUEST_PTY
);
201 translate(SSH1_CMSG_WINDOW_SIZE
);
202 translate(SSH1_CMSG_EXEC_SHELL
);
203 translate(SSH1_CMSG_EXEC_CMD
);
204 translate(SSH1_SMSG_SUCCESS
);
205 translate(SSH1_SMSG_FAILURE
);
206 translate(SSH1_CMSG_STDIN_DATA
);
207 translate(SSH1_SMSG_STDOUT_DATA
);
208 translate(SSH1_SMSG_STDERR_DATA
);
209 translate(SSH1_CMSG_EOF
);
210 translate(SSH1_SMSG_EXIT_STATUS
);
211 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
212 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
213 translate(SSH1_MSG_CHANNEL_DATA
);
214 translate(SSH1_MSG_CHANNEL_CLOSE
);
215 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
216 translate(SSH1_SMSG_X11_OPEN
);
217 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
218 translate(SSH1_MSG_PORT_OPEN
);
219 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
220 translate(SSH1_SMSG_AGENT_OPEN
);
221 translate(SSH1_MSG_IGNORE
);
222 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
223 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
224 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
225 translate(SSH1_MSG_DEBUG
);
226 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
227 translate(SSH1_CMSG_AUTH_TIS
);
228 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
229 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
230 translate(SSH1_CMSG_AUTH_CCARD
);
231 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
232 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
235 char *ssh2_pkt_type(int type
)
237 translate(SSH2_MSG_DISCONNECT
);
238 translate(SSH2_MSG_IGNORE
);
239 translate(SSH2_MSG_UNIMPLEMENTED
);
240 translate(SSH2_MSG_DEBUG
);
241 translate(SSH2_MSG_SERVICE_REQUEST
);
242 translate(SSH2_MSG_SERVICE_ACCEPT
);
243 translate(SSH2_MSG_KEXINIT
);
244 translate(SSH2_MSG_NEWKEYS
);
245 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
246 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
247 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
248 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
249 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
250 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
251 translate(SSH2_MSG_USERAUTH_REQUEST
);
252 translate(SSH2_MSG_USERAUTH_FAILURE
);
253 translate(SSH2_MSG_USERAUTH_SUCCESS
);
254 translate(SSH2_MSG_USERAUTH_BANNER
);
255 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
256 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
257 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
258 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
259 translate(SSH2_MSG_GLOBAL_REQUEST
);
260 translate(SSH2_MSG_REQUEST_SUCCESS
);
261 translate(SSH2_MSG_REQUEST_FAILURE
);
262 translate(SSH2_MSG_CHANNEL_OPEN
);
263 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
264 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
265 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
266 translate(SSH2_MSG_CHANNEL_DATA
);
267 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
268 translate(SSH2_MSG_CHANNEL_EOF
);
269 translate(SSH2_MSG_CHANNEL_CLOSE
);
270 translate(SSH2_MSG_CHANNEL_REQUEST
);
271 translate(SSH2_MSG_CHANNEL_SUCCESS
);
272 translate(SSH2_MSG_CHANNEL_FAILURE
);
278 #define GET_32BIT(cp) \
279 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
280 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
281 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
282 ((unsigned long)(unsigned char)(cp)[3]))
284 #define PUT_32BIT(cp, value) { \
285 (cp)[0] = (unsigned char)((value) >> 24); \
286 (cp)[1] = (unsigned char)((value) >> 16); \
287 (cp)[2] = (unsigned char)((value) >> 8); \
288 (cp)[3] = (unsigned char)(value); }
290 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
292 /* Coroutine mechanics for the sillier bits of the code */
293 #define crBegin1 static int crLine = 0;
294 #define crBegin2 switch(crLine) { case 0:;
295 #define crBegin crBegin1; crBegin2;
296 #define crFinish(z) } crLine = 0; return (z)
297 #define crFinishV } crLine = 0; return
298 #define crReturn(z) \
300 crLine=__LINE__; return (z); case __LINE__:;\
304 crLine=__LINE__; return; case __LINE__:;\
306 #define crStop(z) do{ crLine = 0; return (z); }while(0)
307 #define crStopV do{ crLine = 0; return; }while(0)
308 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
309 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
311 extern char *x11_init(Socket
*, char *, void *);
312 extern void x11_close(Socket
);
313 extern int x11_send(Socket
, char *, int);
314 extern void x11_invent_auth(char *, int, char *, int);
315 extern void x11_unthrottle(Socket s
);
316 extern void x11_override_throttle(Socket s
, int enable
);
318 extern char *pfd_newconnect(Socket
* s
, char *hostname
, int port
, void *c
);
319 extern char *pfd_addforward(char *desthost
, int destport
, int port
);
320 extern void pfd_close(Socket s
);
321 extern int pfd_send(Socket s
, char *data
, int len
);
322 extern void pfd_confirm(Socket s
);
323 extern void pfd_unthrottle(Socket s
);
324 extern void pfd_override_throttle(Socket s
, int enable
);
326 static void ssh2_pkt_init(int pkt_type
);
327 static void ssh2_pkt_addbool(unsigned char value
);
328 static void ssh2_pkt_adduint32(unsigned long value
);
329 static void ssh2_pkt_addstring_start(void);
330 static void ssh2_pkt_addstring_str(char *data
);
331 static void ssh2_pkt_addstring_data(char *data
, int len
);
332 static void ssh2_pkt_addstring(char *data
);
333 static char *ssh2_mpint_fmt(Bignum b
, int *len
);
334 static void ssh2_pkt_addmp(Bignum b
);
335 static int ssh2_pkt_construct(void);
336 static void ssh2_pkt_send(void);
339 * Buffer management constants. There are several of these for
340 * various different purposes:
342 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
343 * on a local data stream before we throttle the whole SSH
344 * connection (in SSH1 only). Throttling the whole connection is
345 * pretty drastic so we set this high in the hope it won't
348 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
349 * on the SSH connection itself before we defensively throttle
350 * _all_ local data streams. This is pretty drastic too (though
351 * thankfully unlikely in SSH2 since the window mechanism should
352 * ensure that the server never has any need to throttle its end
353 * of the connection), so we set this high as well.
355 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
359 #define SSH1_BUFFER_LIMIT 32768
360 #define SSH_MAX_BACKLOG 32768
361 #define OUR_V2_WINSIZE 16384
363 const static struct ssh_kex
*kex_algs
[] = {
364 &ssh_diffiehellman_gex
,
368 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
370 static void nullmac_key(unsigned char *key
)
373 static void nullmac_generate(unsigned char *blk
, int len
,
377 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
)
381 const static struct ssh_mac ssh_mac_none
= {
382 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
384 const static struct ssh_mac
*macs
[] = {
385 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
387 const static struct ssh_mac
*buggymacs
[] = {
388 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
391 static void ssh_comp_none_init(void)
394 static int ssh_comp_none_block(unsigned char *block
, int len
,
395 unsigned char **outblock
, int *outlen
)
399 static int ssh_comp_none_disable(void)
403 const static struct ssh_compress ssh_comp_none
= {
405 ssh_comp_none_init
, ssh_comp_none_block
,
406 ssh_comp_none_init
, ssh_comp_none_block
,
407 ssh_comp_none_disable
409 extern const struct ssh_compress ssh_zlib
;
410 const static struct ssh_compress
*compressions
[] = {
411 &ssh_zlib
, &ssh_comp_none
414 enum { /* channel types */
419 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
423 * 2-3-4 tree storing channels.
426 unsigned remoteid
, localid
;
430 struct ssh1_data_channel
{
433 struct ssh2_data_channel
{
435 unsigned remwindow
, remmaxpkt
;
440 struct ssh_agent_channel
{
441 unsigned char *message
;
442 unsigned char msglen
[4];
443 int lensofar
, totallen
;
445 struct ssh_x11_channel
{
448 struct ssh_pfd_channel
{
455 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
456 * 2 use this structure in different ways, reflecting SSH 2's
457 * altogether saner approach to port forwarding.
459 * In SSH 1, you arrange a remote forwarding by sending the server
460 * the remote port number, and the local destination host:port.
461 * When a connection comes in, the server sends you back that
462 * host:port pair, and you connect to it. This is a ready-made
463 * security hole if you're not on the ball: a malicious server
464 * could send you back _any_ host:port pair, so if you trustingly
465 * connect to the address it gives you then you've just opened the
466 * entire inside of your corporate network just by connecting
467 * through it to a dodgy SSH server. Hence, we must store a list of
468 * host:port pairs we _are_ trying to forward to, and reject a
469 * connection request from the server if it's not in the list.
471 * In SSH 2, each side of the connection minds its own business and
472 * doesn't send unnecessary information to the other. You arrange a
473 * remote forwarding by sending the server just the remote port
474 * number. When a connection comes in, the server tells you which
475 * of its ports was connected to; and _you_ have to remember what
476 * local host:port pair went with that port number.
478 * Hence: in SSH 1 this structure stores host:port pairs we intend
479 * to allow connections to, and is indexed by those host:port
480 * pairs. In SSH 2 it stores a mapping from source port to
481 * destination host:port pair, and is indexed by source port.
483 struct ssh_rportfwd
{
484 unsigned sport
, dport
;
497 static SHA_State exhash
, exhashbase
;
499 static Socket s
= NULL
;
501 static unsigned char session_key
[32];
502 static int ssh1_compressing
;
503 static int ssh1_remote_protoflags
;
504 static int ssh1_local_protoflags
;
505 static int ssh_agentfwd_enabled
;
506 static int ssh_X11_fwd_enabled
;
507 static int ssh_remote_bugs
;
508 static const struct ssh_cipher
*cipher
= NULL
;
509 static const struct ssh2_cipher
*cscipher
= NULL
;
510 static const struct ssh2_cipher
*sccipher
= NULL
;
511 static const struct ssh_mac
*csmac
= NULL
;
512 static const struct ssh_mac
*scmac
= NULL
;
513 static const struct ssh_compress
*cscomp
= NULL
;
514 static const struct ssh_compress
*sccomp
= NULL
;
515 static const struct ssh_kex
*kex
= NULL
;
516 static const struct ssh_signkey
*hostkey
= NULL
;
517 static unsigned char ssh2_session_id
[20];
519 static char *savedhost
;
520 static int savedport
;
521 static int ssh_send_ok
;
522 static int ssh_echoing
, ssh_editing
;
524 static tree234
*ssh_channels
; /* indexed by local id */
525 static struct ssh_channel
*mainchan
; /* primary session channel */
526 static int ssh_exitcode
= -1;
528 static tree234
*ssh_rportfwds
;
532 SSH_STATE_BEFORE_SIZE
,
536 } ssh_state
= SSH_STATE_PREPACKET
;
538 static int size_needed
= FALSE
, eof_needed
= FALSE
;
540 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
541 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
542 static unsigned char *deferred_send_data
= NULL
;
543 static int deferred_len
= 0, deferred_size
= 0;
546 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
547 * that fails. This variable is the means by which scp.c can reach
548 * into the SSH code and find out which one it got.
550 int ssh_fallback_cmd
= 0;
552 static int ssh_version
;
553 static int ssh1_throttle_count
;
554 static int ssh_overall_bufsize
;
555 static int ssh_throttled_all
;
556 static int ssh1_stdout_throttling
;
557 static void (*ssh_protocol
) (unsigned char *in
, int inlen
, int ispkt
);
558 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
559 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
560 static void ssh_size(void);
561 static void ssh_special(Telnet_Special
);
562 static int ssh2_try_send(struct ssh_channel
*c
);
563 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
565 static void ssh_throttle_all(int enable
, int bufsize
);
566 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
567 static int (*s_rdpkt
) (unsigned char **data
, int *datalen
);
568 static int ssh_sendbuffer(void);
570 static struct rdpkt1_state_tag
{
571 long len
, pad
, biglen
, to_read
;
572 unsigned long realcrc
, gotcrc
;
578 static struct rdpkt2_state_tag
{
579 long len
, pad
, payload
, packetlen
, maclen
;
582 unsigned long incoming_sequence
;
585 static int ssh_channelcmp(void *av
, void *bv
)
587 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
588 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
589 if (a
->localid
< b
->localid
)
591 if (a
->localid
> b
->localid
)
595 static int ssh_channelfind(void *av
, void *bv
)
597 unsigned *a
= (unsigned *) av
;
598 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
606 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
608 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
609 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
611 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
612 return i
< 0 ?
-1 : +1;
613 if (a
->dport
> b
->dport
)
615 if (a
->dport
< b
->dport
)
620 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
622 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
623 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
625 if (a
->sport
> b
->sport
)
627 if (a
->sport
< b
->sport
)
632 static int alloc_channel_id(void)
634 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
635 unsigned low
, high
, mid
;
637 struct ssh_channel
*c
;
640 * First-fit allocation of channel numbers: always pick the
641 * lowest unused one. To do this, binary-search using the
642 * counted B-tree to find the largest channel ID which is in a
643 * contiguous sequence from the beginning. (Precisely
644 * everything in that sequence must have ID equal to its tree
645 * index plus CHANNEL_NUMBER_OFFSET.)
647 tsize
= count234(ssh_channels
);
651 while (high
- low
> 1) {
652 mid
= (high
+ low
) / 2;
653 c
= index234(ssh_channels
, mid
);
654 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
655 low
= mid
; /* this one is fine */
657 high
= mid
; /* this one is past it */
660 * Now low points to either -1, or the tree index of the
661 * largest ID in the initial sequence.
664 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
665 assert(NULL
== find234(ssh_channels
, &i
, ssh_channelfind
));
667 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
670 static void c_write(char *buf
, int len
)
672 if ((flags
& FLAG_STDERR
)) {
674 for (i
= 0; i
< len
; i
++)
676 fputc(buf
[i
], stderr
);
679 from_backend(1, buf
, len
);
682 static void c_write_untrusted(char *buf
, int len
)
685 for (i
= 0; i
< len
; i
++) {
688 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
693 static void c_write_str(char *buf
)
695 c_write(buf
, strlen(buf
));
699 * Collect incoming data in the incoming packet buffer.
700 * Decipher and verify the packet when it is completely read.
701 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
702 * Update the *data and *datalen variables.
703 * Return the additional nr of bytes needed, or 0 when
704 * a complete packet is available.
706 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
708 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
717 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
718 while ((*datalen
) == 0)
720 st
->len
= (st
->len
<< 8) + **data
;
721 (*data
)++, (*datalen
)--;
724 st
->pad
= 8 - (st
->len
% 8);
725 st
->biglen
= st
->len
+ st
->pad
;
726 pktin
.length
= st
->len
- 5;
728 if (pktin
.maxlen
< st
->biglen
) {
729 pktin
.maxlen
= st
->biglen
;
730 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+ APIEXTRA
) :
731 srealloc(pktin
.data
, st
->biglen
+ APIEXTRA
));
733 fatalbox("Out of memory");
736 st
->to_read
= st
->biglen
;
738 while (st
->to_read
> 0) {
739 st
->chunk
= st
->to_read
;
740 while ((*datalen
) == 0)
741 crReturn(st
->to_read
);
742 if (st
->chunk
> (*datalen
))
743 st
->chunk
= (*datalen
);
744 memcpy(st
->p
, *data
, st
->chunk
);
746 *datalen
-= st
->chunk
;
748 st
->to_read
-= st
->chunk
;
751 if (cipher
&& detect_attack(pktin
.data
, st
->biglen
, NULL
)) {
752 bombout(("Network attack (CRC compensation) detected!"));
757 cipher
->decrypt(pktin
.data
, st
->biglen
);
759 st
->realcrc
= crc32(pktin
.data
, st
->biglen
- 4);
760 st
->gotcrc
= GET_32BIT(pktin
.data
+ st
->biglen
- 4);
761 if (st
->gotcrc
!= st
->realcrc
) {
762 bombout(("Incorrect CRC received on packet"));
766 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
768 if (ssh1_compressing
) {
769 unsigned char *decompblk
;
771 zlib_decompress_block(pktin
.body
- 1, pktin
.length
+ 1,
772 &decompblk
, &decomplen
);
774 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
775 pktin
.maxlen
= st
->pad
+ decomplen
;
776 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+ APIEXTRA
);
777 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
779 fatalbox("Out of memory");
782 memcpy(pktin
.body
- 1, decompblk
, decomplen
);
784 pktin
.length
= decomplen
- 1;
787 pktin
.type
= pktin
.body
[-1];
789 log_packet(PKT_INCOMING
, pktin
.type
, ssh1_pkt_type(pktin
.type
),
790 pktin
.body
, pktin
.length
);
792 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
793 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
794 pktin
.type
== SSH1_MSG_DEBUG
||
795 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
796 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
797 long stringlen
= GET_32BIT(pktin
.body
);
798 if (stringlen
+ 4 != pktin
.length
) {
799 bombout(("Received data packet with bogus string length"));
804 if (pktin
.type
== SSH1_MSG_DEBUG
) {
805 /* log debug message */
807 int stringlen
= GET_32BIT(pktin
.body
);
808 strcpy(buf
, "Remote: ");
811 memcpy(buf
+ 8, pktin
.body
+ 4, stringlen
);
812 buf
[8 + stringlen
] = '\0';
815 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
820 if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
821 /* log reason code in disconnect message */
823 unsigned msglen
= GET_32BIT(pktin
.body
);
825 strcpy(buf
, "Remote sent disconnect: ");
826 nowlen
= strlen(buf
);
827 if (msglen
> sizeof(buf
) - nowlen
- 1)
828 msglen
= sizeof(buf
) - nowlen
- 1;
829 memcpy(buf
+ nowlen
, pktin
.body
+ 4, msglen
);
830 buf
[nowlen
+ msglen
] = '\0';
831 /* logevent(buf); (this is now done within the bombout macro) */
832 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
839 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
841 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
849 st
->cipherblk
= sccipher
->blksize
;
852 if (st
->cipherblk
< 8)
855 if (pktin
.maxlen
< st
->cipherblk
) {
856 pktin
.maxlen
= st
->cipherblk
;
859 NULL ?
smalloc(st
->cipherblk
+
860 APIEXTRA
) : srealloc(pktin
.data
,
864 fatalbox("Out of memory");
868 * Acquire and decrypt the first block of the packet. This will
869 * contain the length and padding details.
871 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
872 while ((*datalen
) == 0)
873 crReturn(st
->cipherblk
- st
->i
);
874 pktin
.data
[st
->i
] = *(*data
)++;
879 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
882 * Now get the length and padding figures.
884 st
->len
= GET_32BIT(pktin
.data
);
885 st
->pad
= pktin
.data
[4];
888 * _Completely_ silly lengths should be stomped on before they
889 * do us any more damage.
891 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
892 bombout(("Incoming packet was garbled on decryption"));
897 * This enables us to deduce the payload length.
899 st
->payload
= st
->len
- st
->pad
- 1;
901 pktin
.length
= st
->payload
+ 5;
904 * So now we can work out the total packet length.
906 st
->packetlen
= st
->len
+ 4;
907 st
->maclen
= scmac ? scmac
->len
: 0;
910 * Adjust memory allocation if packet is too big.
912 if (pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
913 pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
916 NULL ?
smalloc(pktin
.maxlen
+ APIEXTRA
) : srealloc(pktin
.data
,
921 fatalbox("Out of memory");
925 * Read and decrypt the remainder of the packet.
927 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
929 while ((*datalen
) == 0)
930 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
931 pktin
.data
[st
->i
] = *(*data
)++;
934 /* Decrypt everything _except_ the MAC. */
936 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
937 st
->packetlen
- st
->cipherblk
);
943 && !scmac
->verify(pktin
.data
, st
->len
+ 4,
944 st
->incoming_sequence
)) {
945 bombout(("Incorrect MAC received on packet"));
948 st
->incoming_sequence
++; /* whether or not we MACed */
951 * Decompress packet payload.
954 unsigned char *newpayload
;
956 if (sccomp
&& sccomp
->decompress(pktin
.data
+ 5, pktin
.length
- 5,
957 &newpayload
, &newlen
)) {
958 if (pktin
.maxlen
< newlen
+ 5) {
959 pktin
.maxlen
= newlen
+ 5;
962 NULL ?
smalloc(pktin
.maxlen
+
963 APIEXTRA
) : srealloc(pktin
.data
,
967 fatalbox("Out of memory");
969 pktin
.length
= 5 + newlen
;
970 memcpy(pktin
.data
+ 5, newpayload
, newlen
);
976 pktin
.type
= pktin
.data
[5];
978 log_packet(PKT_INCOMING
, pktin
.type
, ssh2_pkt_type(pktin
.type
),
979 pktin
.data
+6, pktin
.length
-6);
981 switch (pktin
.type
) {
983 * These packets we must handle instantly.
985 case SSH2_MSG_DISCONNECT
:
987 /* log reason code in disconnect message */
989 int reason
= GET_32BIT(pktin
.data
+ 6);
990 unsigned msglen
= GET_32BIT(pktin
.data
+ 10);
992 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
993 sprintf(buf
, "Received disconnect message (%s)",
994 ssh2_disconnect_reasons
[reason
]);
996 sprintf(buf
, "Received disconnect message (unknown type %d)",
1000 strcpy(buf
, "Disconnection message text: ");
1001 nowlen
= strlen(buf
);
1002 if (msglen
> sizeof(buf
) - nowlen
- 1)
1003 msglen
= sizeof(buf
) - nowlen
- 1;
1004 memcpy(buf
+ nowlen
, pktin
.data
+ 14, msglen
);
1005 buf
[nowlen
+ msglen
] = '\0';
1007 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1009 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1010 ssh2_disconnect_reasons
[reason
] : "unknown",
1015 case SSH2_MSG_IGNORE
:
1017 case SSH2_MSG_DEBUG
:
1019 /* log the debug message */
1021 /* int display = pktin.body[6]; */
1022 int stringlen
= GET_32BIT(pktin
.data
+7);
1024 strcpy(buf
, "Remote debug message: ");
1025 prefix
= strlen(buf
);
1026 if (stringlen
> sizeof(buf
)-prefix
-1)
1027 stringlen
= sizeof(buf
)-prefix
-1;
1028 memcpy(buf
+ prefix
, pktin
.data
+ 11, stringlen
);
1029 buf
[prefix
+ stringlen
] = '\0';
1032 goto next_packet
; /* FIXME: print the debug message */
1035 * These packets we need do nothing about here.
1037 case SSH2_MSG_UNIMPLEMENTED
:
1038 case SSH2_MSG_SERVICE_REQUEST
:
1039 case SSH2_MSG_SERVICE_ACCEPT
:
1040 case SSH2_MSG_KEXINIT
:
1041 case SSH2_MSG_NEWKEYS
:
1042 case SSH2_MSG_KEXDH_INIT
:
1043 case SSH2_MSG_KEXDH_REPLY
:
1044 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1045 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1046 case SSH2_MSG_KEX_DH_GEX_INIT
:
1047 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1048 case SSH2_MSG_USERAUTH_REQUEST
:
1049 case SSH2_MSG_USERAUTH_FAILURE
:
1050 case SSH2_MSG_USERAUTH_SUCCESS
:
1051 case SSH2_MSG_USERAUTH_BANNER
:
1052 case SSH2_MSG_USERAUTH_PK_OK
:
1053 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1054 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1055 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1056 case SSH2_MSG_GLOBAL_REQUEST
:
1057 case SSH2_MSG_REQUEST_SUCCESS
:
1058 case SSH2_MSG_REQUEST_FAILURE
:
1059 case SSH2_MSG_CHANNEL_OPEN
:
1060 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1061 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1062 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1063 case SSH2_MSG_CHANNEL_DATA
:
1064 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1065 case SSH2_MSG_CHANNEL_EOF
:
1066 case SSH2_MSG_CHANNEL_CLOSE
:
1067 case SSH2_MSG_CHANNEL_REQUEST
:
1068 case SSH2_MSG_CHANNEL_SUCCESS
:
1069 case SSH2_MSG_CHANNEL_FAILURE
:
1073 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1076 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
1077 ssh2_pkt_adduint32(st
->incoming_sequence
- 1);
1085 static void ssh1_pktout_size(int len
)
1089 len
+= 5; /* type and CRC */
1090 pad
= 8 - (len
% 8);
1093 pktout
.length
= len
- 5;
1094 if (pktout
.maxlen
< biglen
) {
1095 pktout
.maxlen
= biglen
;
1097 /* Allocate enough buffer space for extra block
1098 * for MS CryptEncrypt() */
1099 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 12) :
1100 srealloc(pktout
.data
, biglen
+ 12));
1102 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 4) :
1103 srealloc(pktout
.data
, biglen
+ 4));
1106 fatalbox("Out of memory");
1108 pktout
.body
= pktout
.data
+ 4 + pad
+ 1;
1111 static void s_wrpkt_start(int type
, int len
)
1113 ssh1_pktout_size(len
);
1117 static int s_wrpkt_prepare(void)
1119 int pad
, len
, biglen
, i
;
1122 pktout
.body
[-1] = pktout
.type
;
1124 log_packet(PKT_OUTGOING
, pktout
.type
, ssh1_pkt_type(pktout
.type
),
1125 pktout
.body
, pktout
.length
);
1127 if (ssh1_compressing
) {
1128 unsigned char *compblk
;
1130 zlib_compress_block(pktout
.body
- 1, pktout
.length
+ 1,
1131 &compblk
, &complen
);
1132 ssh1_pktout_size(complen
- 1);
1133 memcpy(pktout
.body
- 1, compblk
, complen
);
1137 len
= pktout
.length
+ 5; /* type and CRC */
1138 pad
= 8 - (len
% 8);
1141 for (i
= 0; i
< pad
; i
++)
1142 pktout
.data
[i
+ 4] = random_byte();
1143 crc
= crc32(pktout
.data
+ 4, biglen
- 4);
1144 PUT_32BIT(pktout
.data
+ biglen
, crc
);
1145 PUT_32BIT(pktout
.data
, len
);
1148 cipher
->encrypt(pktout
.data
+ 4, biglen
);
1153 static void s_wrpkt(void)
1156 len
= s_wrpkt_prepare();
1157 backlog
= sk_write(s
, pktout
.data
, len
);
1158 if (backlog
> SSH_MAX_BACKLOG
)
1159 ssh_throttle_all(1, backlog
);
1162 static void s_wrpkt_defer(void)
1165 len
= s_wrpkt_prepare();
1166 if (deferred_len
+ len
> deferred_size
) {
1167 deferred_size
= deferred_len
+ len
+ 128;
1168 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1170 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1171 deferred_len
+= len
;
1175 * Construct a packet with the specified contents.
1177 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
1179 unsigned char *p
, *argp
, argchar
;
1180 unsigned long argint
;
1181 int pktlen
, argtype
, arglen
;
1185 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1188 (void) va_arg(ap1
, int);
1192 (void) va_arg(ap1
, char);
1196 (void) va_arg(ap1
, unsigned char *);
1197 arglen
= va_arg(ap1
, int);
1201 argp
= va_arg(ap1
, unsigned char *);
1202 arglen
= strlen(argp
);
1203 pktlen
+= 4 + arglen
;
1206 bn
= va_arg(ap1
, Bignum
);
1207 pktlen
+= ssh1_bignum_length(bn
);
1214 s_wrpkt_start(pkttype
, pktlen
);
1217 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1220 argint
= va_arg(ap2
, int);
1221 PUT_32BIT(p
, argint
);
1225 argchar
= va_arg(ap2
, unsigned char);
1230 argp
= va_arg(ap2
, unsigned char *);
1231 arglen
= va_arg(ap2
, int);
1232 memcpy(p
, argp
, arglen
);
1236 argp
= va_arg(ap2
, unsigned char *);
1237 arglen
= strlen(argp
);
1238 PUT_32BIT(p
, arglen
);
1239 memcpy(p
+ 4, argp
, arglen
);
1243 bn
= va_arg(ap2
, Bignum
);
1244 p
+= ssh1_write_bignum(p
, bn
);
1250 static void send_packet(int pkttype
, ...)
1253 va_start(ap1
, pkttype
);
1254 va_start(ap2
, pkttype
);
1255 construct_packet(pkttype
, ap1
, ap2
);
1259 static void defer_packet(int pkttype
, ...)
1262 va_start(ap1
, pkttype
);
1263 va_start(ap2
, pkttype
);
1264 construct_packet(pkttype
, ap1
, ap2
);
1268 static int ssh_versioncmp(char *a
, char *b
)
1271 unsigned long av
, bv
;
1273 av
= strtoul(a
, &ae
, 10);
1274 bv
= strtoul(b
, &be
, 10);
1276 return (av
< bv ?
-1 : +1);
1281 av
= strtoul(ae
, &ae
, 10);
1282 bv
= strtoul(be
, &be
, 10);
1284 return (av
< bv ?
-1 : +1);
1290 * Utility routines for putting an SSH-protocol `string' and
1291 * `uint32' into a SHA state.
1294 static void sha_string(SHA_State
* s
, void *str
, int len
)
1296 unsigned char lenblk
[4];
1297 PUT_32BIT(lenblk
, len
);
1298 SHA_Bytes(s
, lenblk
, 4);
1299 SHA_Bytes(s
, str
, len
);
1302 static void sha_uint32(SHA_State
* s
, unsigned i
)
1304 unsigned char intblk
[4];
1305 PUT_32BIT(intblk
, i
);
1306 SHA_Bytes(s
, intblk
, 4);
1310 * SSH2 packet construction functions.
1312 static void ssh2_pkt_ensure(int length
)
1314 if (pktout
.maxlen
< length
) {
1315 pktout
.maxlen
= length
+ 256;
1318 NULL ?
smalloc(pktout
.maxlen
+
1319 APIEXTRA
) : srealloc(pktout
.data
,
1323 fatalbox("Out of memory");
1326 static void ssh2_pkt_adddata(void *data
, int len
)
1328 pktout
.length
+= len
;
1329 ssh2_pkt_ensure(pktout
.length
);
1330 memcpy(pktout
.data
+ pktout
.length
- len
, data
, len
);
1332 static void ssh2_pkt_addbyte(unsigned char byte
)
1334 ssh2_pkt_adddata(&byte
, 1);
1336 static void ssh2_pkt_init(int pkt_type
)
1339 ssh2_pkt_addbyte((unsigned char) pkt_type
);
1341 static void ssh2_pkt_addbool(unsigned char value
)
1343 ssh2_pkt_adddata(&value
, 1);
1345 static void ssh2_pkt_adduint32(unsigned long value
)
1348 PUT_32BIT(x
, value
);
1349 ssh2_pkt_adddata(x
, 4);
1351 static void ssh2_pkt_addstring_start(void)
1353 ssh2_pkt_adduint32(0);
1354 pktout
.savedpos
= pktout
.length
;
1356 static void ssh2_pkt_addstring_str(char *data
)
1358 ssh2_pkt_adddata(data
, strlen(data
));
1359 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1360 pktout
.length
- pktout
.savedpos
);
1362 static void ssh2_pkt_addstring_data(char *data
, int len
)
1364 ssh2_pkt_adddata(data
, len
);
1365 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1366 pktout
.length
- pktout
.savedpos
);
1368 static void ssh2_pkt_addstring(char *data
)
1370 ssh2_pkt_addstring_start();
1371 ssh2_pkt_addstring_str(data
);
1373 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1376 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1379 fatalbox("out of memory");
1381 for (i
= 1; i
<= n
; i
++)
1382 p
[i
] = bignum_byte(b
, n
- i
);
1384 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1386 memmove(p
, p
+ i
, n
+ 1 - i
);
1390 static void ssh2_pkt_addmp(Bignum b
)
1394 p
= ssh2_mpint_fmt(b
, &len
);
1395 ssh2_pkt_addstring_start();
1396 ssh2_pkt_addstring_data(p
, len
);
1401 * Construct an SSH2 final-form packet: compress it, encrypt it,
1402 * put the MAC on it. Final packet, ready to be sent, is stored in
1403 * pktout.data. Total length is returned.
1405 static int ssh2_pkt_construct(void)
1407 int cipherblk
, maclen
, padding
, i
;
1408 static unsigned long outgoing_sequence
= 0;
1410 log_packet(PKT_OUTGOING
, pktout
.data
[5], ssh2_pkt_type(pktout
.data
[5]),
1411 pktout
.data
+ 6, pktout
.length
- 6);
1414 * Compress packet payload.
1417 unsigned char *newpayload
;
1419 if (cscomp
&& cscomp
->compress(pktout
.data
+ 5, pktout
.length
- 5,
1420 &newpayload
, &newlen
)) {
1422 ssh2_pkt_adddata(newpayload
, newlen
);
1428 * Add padding. At least four bytes, and must also bring total
1429 * length (minus MAC) up to a multiple of the block size.
1431 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
1432 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1435 (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1436 maclen
= csmac ? csmac
->len
: 0;
1437 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
1438 pktout
.data
[4] = padding
;
1439 for (i
= 0; i
< padding
; i
++)
1440 pktout
.data
[pktout
.length
+ i
] = random_byte();
1441 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
1443 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
1445 outgoing_sequence
++; /* whether or not we MACed */
1448 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
1450 /* Ready-to-send packet starts at pktout.data. We return length. */
1451 return pktout
.length
+ padding
+ maclen
;
1455 * Construct and send an SSH2 packet immediately.
1457 static void ssh2_pkt_send(void)
1461 len
= ssh2_pkt_construct();
1462 backlog
= sk_write(s
, pktout
.data
, len
);
1463 if (backlog
> SSH_MAX_BACKLOG
)
1464 ssh_throttle_all(1, backlog
);
1468 * Construct an SSH2 packet and add it to a deferred data block.
1469 * Useful for sending multiple packets in a single sk_write() call,
1470 * to prevent a traffic-analysing listener from being able to work
1471 * out the length of any particular packet (such as the password
1474 * Note that because SSH2 sequence-numbers its packets, this can
1475 * NOT be used as an m4-style `defer' allowing packets to be
1476 * constructed in one order and sent in another.
1478 static void ssh2_pkt_defer(void)
1480 int len
= ssh2_pkt_construct();
1481 if (deferred_len
+ len
> deferred_size
) {
1482 deferred_size
= deferred_len
+ len
+ 128;
1483 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1485 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1486 deferred_len
+= len
;
1490 * Send the whole deferred data block constructed by
1491 * ssh2_pkt_defer() or SSH1's defer_packet().
1493 static void ssh_pkt_defersend(void)
1496 backlog
= sk_write(s
, deferred_send_data
, deferred_len
);
1497 deferred_len
= deferred_size
= 0;
1498 sfree(deferred_send_data
);
1499 deferred_send_data
= NULL
;
1500 if (backlog
> SSH_MAX_BACKLOG
)
1501 ssh_throttle_all(1, backlog
);
1505 void bndebug(char *string
, Bignum b
)
1509 p
= ssh2_mpint_fmt(b
, &len
);
1510 debug(("%s", string
));
1511 for (i
= 0; i
< len
; i
++)
1512 debug((" %02x", p
[i
]));
1518 static void sha_mpint(SHA_State
* s
, Bignum b
)
1522 p
= ssh2_mpint_fmt(b
, &len
);
1523 sha_string(s
, p
, len
);
1528 * SSH2 packet decode functions.
1530 static unsigned long ssh2_pkt_getuint32(void)
1532 unsigned long value
;
1533 if (pktin
.length
- pktin
.savedpos
< 4)
1534 return 0; /* arrgh, no way to decline (FIXME?) */
1535 value
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1536 pktin
.savedpos
+= 4;
1539 static int ssh2_pkt_getbool(void)
1541 unsigned long value
;
1542 if (pktin
.length
- pktin
.savedpos
< 1)
1543 return 0; /* arrgh, no way to decline (FIXME?) */
1544 value
= pktin
.data
[pktin
.savedpos
] != 0;
1548 static void ssh2_pkt_getstring(char **p
, int *length
)
1552 if (pktin
.length
- pktin
.savedpos
< 4)
1554 *length
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1555 pktin
.savedpos
+= 4;
1556 if (pktin
.length
- pktin
.savedpos
< *length
)
1558 *p
= pktin
.data
+ pktin
.savedpos
;
1559 pktin
.savedpos
+= *length
;
1561 static Bignum
ssh2_pkt_getmp(void)
1567 ssh2_pkt_getstring(&p
, &length
);
1571 bombout(("internal error: Can't handle negative mpints"));
1574 b
= bignum_from_bytes(p
, length
);
1579 * Helper function to add an SSH2 signature blob to a packet.
1580 * Expects to be shown the public key blob as well as the signature
1581 * blob. Normally works just like ssh2_pkt_addstring, but will
1582 * fiddle with the signature packet if necessary for
1583 * BUG_SSH2_RSA_PADDING.
1585 static void ssh2_add_sigblob(void *pkblob_v
, int pkblob_len
,
1586 void *sigblob_v
, int sigblob_len
)
1588 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1589 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1591 /* dmemdump(pkblob, pkblob_len); */
1592 /* dmemdump(sigblob, sigblob_len); */
1595 * See if this is in fact an ssh-rsa signature and a buggy
1596 * server; otherwise we can just do this the easy way.
1598 if ((ssh_remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1599 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1600 int pos
, len
, siglen
;
1603 * Find the byte length of the modulus.
1606 pos
= 4+7; /* skip over "ssh-rsa" */
1607 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1608 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1609 pos
+= 4; /* find modulus itself */
1610 while (len
> 0 && pkblob
[pos
] == 0)
1612 /* debug(("modulus length is %d\n", len)); */
1615 * Now find the signature integer.
1617 pos
= 4+7; /* skip over "ssh-rsa" */
1618 siglen
= GET_32BIT(sigblob
+pos
);
1619 /* debug(("signature length is %d\n", siglen)); */
1621 if (len
!= siglen
) {
1622 unsigned char newlen
[4];
1623 ssh2_pkt_addstring_start();
1624 ssh2_pkt_addstring_data(sigblob
, pos
);
1625 /* dmemdump(sigblob, pos); */
1626 pos
+= 4; /* point to start of actual sig */
1627 PUT_32BIT(newlen
, len
);
1628 ssh2_pkt_addstring_data(newlen
, 4);
1629 /* dmemdump(newlen, 4); */
1631 while (len
-- > siglen
) {
1632 ssh2_pkt_addstring_data(newlen
, 1);
1633 /* dmemdump(newlen, 1); */
1635 ssh2_pkt_addstring_data(sigblob
+pos
, siglen
);
1636 /* dmemdump(sigblob+pos, siglen); */
1640 /* Otherwise fall through and do it the easy way. */
1643 ssh2_pkt_addstring_start();
1644 ssh2_pkt_addstring_data(sigblob
, sigblob_len
);
1648 * Examine the remote side's version string and compare it against
1649 * a list of known buggy implementations.
1651 static void ssh_detect_bugs(char *vstring
)
1653 char *imp
; /* pointer to implementation part */
1655 imp
+= strcspn(imp
, "-");
1657 imp
+= strcspn(imp
, "-");
1660 ssh_remote_bugs
= 0;
1662 if (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1663 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1664 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")) {
1666 * These versions don't support SSH1_MSG_IGNORE, so we have
1667 * to use a different defence against password length
1670 ssh_remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1671 logevent("We believe remote version has SSH1 ignore bug");
1674 if (!strcmp(imp
, "Cisco-1.25")) {
1676 * These versions need a plain password sent; they can't
1677 * handle having a null and a random length of data after
1680 ssh_remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1681 logevent("We believe remote version needs a plain SSH1 password");
1684 if (!strcmp(imp
, "Cisco-1.25")) {
1686 * These versions apparently have no clue whatever about
1687 * RSA authentication and will panic and die if they see
1688 * an AUTH_RSA message.
1690 ssh_remote_bugs
|= BUG_CHOKES_ON_RSA
;
1691 logevent("We believe remote version can't handle RSA authentication");
1694 if (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1695 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1696 !strncmp(imp
, "2.1 ", 4)) {
1698 * These versions have the HMAC bug.
1700 ssh_remote_bugs
|= BUG_SSH2_HMAC
;
1701 logevent("We believe remote version has SSH2 HMAC bug");
1704 if ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1705 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')) {
1707 * These versions have the SSH2 RSA padding bug.
1709 ssh_remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1710 logevent("We believe remote version has SSH2 RSA padding bug");
1714 static int do_ssh_init(unsigned char c
)
1717 static char version
[10];
1718 static char *vstring
;
1719 static int vstrsize
;
1722 static int proto1
, proto2
;
1726 /* Search for the string "SSH-" in the input. */
1729 static const int transS
[] = { 1, 2, 2, 1 };
1730 static const int transH
[] = { 0, 0, 3, 0 };
1731 static const int transminus
[] = { 0, 0, 0, -1 };
1742 crReturn(1); /* get another character */
1746 vstring
= smalloc(vstrsize
);
1747 strcpy(vstring
, "SSH-");
1751 crReturn(1); /* get another char */
1752 if (vslen
>= vstrsize
- 1) {
1754 vstring
= srealloc(vstring
, vstrsize
);
1756 vstring
[vslen
++] = c
;
1761 } else if (i
< sizeof(version
) - 1)
1763 } else if (c
== '\n')
1767 ssh_agentfwd_enabled
= FALSE
;
1768 rdpkt2_state
.incoming_sequence
= 0;
1771 vlog
= smalloc(20 + vslen
);
1772 vstring
[strcspn (vstring
, "\r\n")] = '\0'; /* remove end-of-line chars */
1773 sprintf(vlog
, "Server version: %s", vstring
);
1775 ssh_detect_bugs(vstring
);
1779 * Decide which SSH protocol version to support.
1782 /* Anything strictly below "2.0" means protocol 1 is supported. */
1783 proto1
= ssh_versioncmp(version
, "2.0") < 0;
1784 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1785 proto2
= ssh_versioncmp(version
, "1.99") >= 0;
1787 if (cfg
.sshprot
== 0 && !proto1
) {
1788 bombout(("SSH protocol version 1 required by user but not provided by server"));
1791 if (cfg
.sshprot
== 3 && !proto2
) {
1792 bombout(("SSH protocol version 2 required by user but not provided by server"));
1796 if (proto2
&& (cfg
.sshprot
>= 2 || !proto1
)) {
1800 char verstring
[80], vlog
[100];
1801 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1802 SHA_Init(&exhashbase
);
1804 * Hash our version string and their version string.
1806 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1807 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1808 sprintf(vlog
, "We claim version: %s", verstring
);
1810 strcat(verstring
, "\n");
1811 logevent("Using SSH protocol version 2");
1812 sk_write(s
, verstring
, strlen(verstring
));
1813 ssh_protocol
= ssh2_protocol
;
1815 s_rdpkt
= ssh2_rdpkt
;
1820 char verstring
[80], vlog
[100];
1821 sprintf(verstring
, "SSH-%s-%s",
1822 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"),
1824 sprintf(vlog
, "We claim version: %s", verstring
);
1826 strcat(verstring
, "\n");
1828 logevent("Using SSH protocol version 1");
1829 sk_write(s
, verstring
, strlen(verstring
));
1830 ssh_protocol
= ssh1_protocol
;
1832 s_rdpkt
= ssh1_rdpkt
;
1834 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1841 static void ssh_gotdata(unsigned char *data
, int datalen
)
1846 * To begin with, feed the characters one by one to the
1847 * protocol initialisation / selection function do_ssh_init().
1848 * When that returns 0, we're done with the initial greeting
1849 * exchange and can move on to packet discipline.
1854 crReturnV
; /* more data please */
1855 ret
= do_ssh_init(*data
);
1863 * We emerge from that loop when the initial negotiation is
1864 * over and we have selected an s_rdpkt function. Now pass
1865 * everything to s_rdpkt, and then pass the resulting packets
1866 * to the proper protocol handler.
1871 while (datalen
> 0) {
1872 if (s_rdpkt(&data
, &datalen
) == 0) {
1873 if (ssh_state
== SSH_STATE_CLOSED
) {
1876 ssh_protocol(NULL
, 0, 1);
1877 if (ssh_state
== SSH_STATE_CLOSED
) {
1887 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1890 ssh_state
= SSH_STATE_CLOSED
;
1896 /* A socket error has occurred. */
1897 logevent(error_msg
);
1898 connection_fatal(error_msg
);
1900 /* Otherwise, the remote side closed the connection normally. */
1905 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1907 ssh_gotdata(data
, len
);
1908 if (ssh_state
== SSH_STATE_CLOSED
) {
1918 static void ssh_sent(Plug plug
, int bufsize
)
1921 * If the send backlog on the SSH socket itself clears, we
1922 * should unthrottle the whole world if it was throttled.
1924 if (bufsize
< SSH_MAX_BACKLOG
)
1925 ssh_throttle_all(0, bufsize
);
1929 * Connect to specified host and port.
1930 * Returns an error message, or NULL on success.
1931 * Also places the canonical host name into `realhost'. It must be
1932 * freed by the caller.
1934 static char *connect_to_host(char *host
, int port
, char **realhost
, int nodelay
)
1936 static struct plug_function_table fn_table
= {
1941 }, *fn_table_ptr
= &fn_table
;
1950 savedhost
= smalloc(1 + strlen(host
));
1952 fatalbox("Out of memory");
1953 strcpy(savedhost
, host
);
1956 port
= 22; /* default ssh port */
1971 sprintf(buf
, "Looking up host \"%.170s\"", host
);
1974 addr
= sk_namelookup(host
, realhost
);
1975 if ((err
= sk_addr_error(addr
)))
1979 *realhost
= strdup(FWhost
);
1986 char buf
[200], addrbuf
[100];
1987 sk_getaddr(addr
, addrbuf
, 100);
1988 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
1991 s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, &fn_table_ptr
);
1992 if ((err
= sk_socket_error(s
))) {
1998 sk_write(s
, "connect ", 8);
1999 sk_write(s
, FWhost
, strlen(FWhost
));
2002 sprintf(buf
, " %d\n", FWport
);
2003 sk_write(s
, buf
, strlen(buf
));
2011 * Throttle or unthrottle the SSH connection.
2013 static void ssh1_throttle(int adjust
)
2015 int old_count
= ssh1_throttle_count
;
2016 ssh1_throttle_count
+= adjust
;
2017 assert(ssh1_throttle_count
>= 0);
2018 if (ssh1_throttle_count
&& !old_count
) {
2019 sk_set_frozen(s
, 1);
2020 } else if (!ssh1_throttle_count
&& old_count
) {
2021 sk_set_frozen(s
, 0);
2026 * Throttle or unthrottle _all_ local data streams (for when sends
2027 * on the SSH connection itself back up).
2029 static void ssh_throttle_all(int enable
, int bufsize
)
2032 struct ssh_channel
*c
;
2034 if (enable
== ssh_throttled_all
)
2036 ssh_throttled_all
= enable
;
2037 ssh_overall_bufsize
= bufsize
;
2040 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
2042 case CHAN_MAINSESSION
:
2044 * This is treated separately, outside the switch.
2048 x11_override_throttle(c
->u
.x11
.s
, enable
);
2051 /* Agent channels require no buffer management. */
2054 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2061 * Username and password input, abstracted off into reusable
2062 * routines (hopefully even reusable between SSH1 and SSH2!).
2064 static char *ssh_userpass_input_buffer
;
2065 static int ssh_userpass_input_buflen
;
2066 static int ssh_userpass_input_bufpos
;
2067 static int ssh_userpass_input_echo
;
2069 /* Set up a username or password input loop on a given buffer. */
2070 void setup_userpass_input(char *buffer
, int buflen
, int echo
)
2072 ssh_userpass_input_buffer
= buffer
;
2073 ssh_userpass_input_buflen
= buflen
;
2074 ssh_userpass_input_bufpos
= 0;
2075 ssh_userpass_input_echo
= echo
;
2079 * Process some terminal data in the course of username/password
2080 * input. Returns >0 for success (line of input returned in
2081 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2082 * for inconclusive (keep waiting for more input please).
2084 int process_userpass_input(unsigned char *in
, int inlen
)
2089 switch (c
= *in
++) {
2092 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
] = 0;
2093 ssh_userpass_input_buffer
[ssh_userpass_input_buflen
-1] = 0;
2098 if (ssh_userpass_input_bufpos
> 0) {
2099 if (ssh_userpass_input_echo
)
2100 c_write_str("\b \b");
2101 ssh_userpass_input_bufpos
--;
2106 while (ssh_userpass_input_bufpos
> 0) {
2107 if (ssh_userpass_input_echo
)
2108 c_write_str("\b \b");
2109 ssh_userpass_input_bufpos
--;
2117 if (((c
>= ' ' && c
<= '~') ||
2118 ((unsigned char) c
>= 160))
2119 && ssh_userpass_input_bufpos
< ssh_userpass_input_buflen
-1) {
2120 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
++] = c
;
2121 if (ssh_userpass_input_echo
)
2131 * Handle the key exchange and user authentication phases.
2133 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
2137 static unsigned char *rsabuf
, *keystr1
, *keystr2
;
2138 unsigned char cookie
[8];
2139 struct RSAKey servkey
, hostkey
;
2140 struct MD5Context md5c
;
2141 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
2142 static int tried_publickey
, tried_agent
;
2143 static int tis_auth_refused
, ccard_auth_refused
;
2144 static unsigned char session_id
[16];
2145 static int cipher_type
;
2146 static char username
[100];
2147 static void *publickey_blob
;
2148 int publickey_bloblen
;
2155 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2156 bombout(("Public key packet not received"));
2160 logevent("Received public keys");
2162 memcpy(cookie
, pktin
.body
, 8);
2164 i
= makekey(pktin
.body
+ 8, &servkey
, &keystr1
, 0);
2165 j
= makekey(pktin
.body
+ 8 + i
, &hostkey
, &keystr2
, 0);
2168 * Log the host key fingerprint.
2172 logevent("Host key fingerprint is:");
2173 strcpy(logmsg
, " ");
2174 hostkey
.comment
= NULL
;
2175 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2176 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2180 ssh1_remote_protoflags
= GET_32BIT(pktin
.body
+ 8 + i
+ j
);
2181 supported_ciphers_mask
= GET_32BIT(pktin
.body
+ 12 + i
+ j
);
2182 supported_auths_mask
= GET_32BIT(pktin
.body
+ 16 + i
+ j
);
2184 ssh1_local_protoflags
=
2185 ssh1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2186 ssh1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2189 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
2190 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
2191 MD5Update(&md5c
, pktin
.body
, 8);
2192 MD5Final(session_id
, &md5c
);
2194 for (i
= 0; i
< 32; i
++)
2195 session_key
[i
] = random_byte();
2197 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2199 rsabuf
= smalloc(len
);
2201 fatalbox("Out of memory");
2204 * Verify the host key.
2208 * First format the key into a string.
2210 int len
= rsastr_len(&hostkey
);
2211 char fingerprint
[100];
2212 char *keystr
= smalloc(len
);
2214 fatalbox("Out of memory");
2215 rsastr_fmt(keystr
, &hostkey
);
2216 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2217 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
,
2222 for (i
= 0; i
< 32; i
++) {
2223 rsabuf
[i
] = session_key
[i
];
2225 rsabuf
[i
] ^= session_id
[i
];
2228 if (hostkey
.bytes
> servkey
.bytes
) {
2229 rsaencrypt(rsabuf
, 32, &servkey
);
2230 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
2232 rsaencrypt(rsabuf
, 32, &hostkey
);
2233 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
2236 logevent("Encrypted session key");
2239 int cipher_chosen
= 0, warn
= 0;
2240 char *cipher_string
= NULL
;
2241 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2242 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2243 if (next_cipher
== CIPHER_WARN
) {
2244 /* If/when we choose a cipher, warn about it */
2246 } else if (next_cipher
== CIPHER_AES
) {
2247 /* XXX Probably don't need to mention this. */
2248 logevent("AES not supported in SSH1, skipping");
2250 switch (next_cipher
) {
2251 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
;
2252 cipher_string
= "3DES"; break;
2253 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
;
2254 cipher_string
= "Blowfish"; break;
2255 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
;
2256 cipher_string
= "single-DES"; break;
2258 if (supported_ciphers_mask
& (1 << cipher_type
))
2262 if (!cipher_chosen
) {
2263 if ((supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2264 bombout(("Server violates SSH 1 protocol by not "
2265 "supporting 3DES encryption"));
2267 /* shouldn't happen */
2268 bombout(("No supported ciphers found"));
2272 /* Warn about chosen cipher if necessary. */
2274 askcipher(cipher_string
, 0);
2277 switch (cipher_type
) {
2278 case SSH_CIPHER_3DES
:
2279 logevent("Using 3DES encryption");
2281 case SSH_CIPHER_DES
:
2282 logevent("Using single-DES encryption");
2284 case SSH_CIPHER_BLOWFISH
:
2285 logevent("Using Blowfish encryption");
2289 send_packet(SSH1_CMSG_SESSION_KEY
,
2290 PKT_CHAR
, cipher_type
,
2291 PKT_DATA
, cookie
, 8,
2292 PKT_CHAR
, (len
* 8) >> 8, PKT_CHAR
, (len
* 8) & 0xFF,
2293 PKT_DATA
, rsabuf
, len
,
2294 PKT_INT
, ssh1_local_protoflags
, PKT_END
);
2296 logevent("Trying to enable encryption...");
2300 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2301 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
: &ssh_3des
;
2302 cipher
->sesskey(session_key
);
2306 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2307 bombout(("Encryption not successfully enabled"));
2311 logevent("Successfully started encryption");
2315 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2316 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2317 if (!ssh_get_line("login as: ",
2318 username
, sizeof(username
), FALSE
)) {
2320 * get_line failed to get a username.
2323 logevent("No username provided. Abandoning session.");
2324 ssh_state
= SSH_STATE_CLOSED
;
2329 c_write_str("login as: ");
2332 setup_userpass_input(username
, sizeof(username
), 1);
2334 crWaitUntil(!ispkt
);
2335 ret
= process_userpass_input(in
, inlen
);
2339 c_write_str("\r\n");
2342 strncpy(username
, cfg
.username
, 99);
2343 username
[99] = '\0';
2346 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
2348 char userlog
[22 + sizeof(username
)];
2349 sprintf(userlog
, "Sent username \"%s\"", username
);
2351 if (flags
& FLAG_INTERACTIVE
&&
2352 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2353 strcat(userlog
, "\r\n");
2354 c_write_str(userlog
);
2361 if ((ssh_remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2362 /* We must not attempt PK auth. Pretend we've already tried it. */
2363 tried_publickey
= tried_agent
= 1;
2365 tried_publickey
= tried_agent
= 0;
2367 tis_auth_refused
= ccard_auth_refused
= 0;
2368 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2370 if (!rsakey_pubblob(cfg
.keyfile
, &publickey_blob
, &publickey_bloblen
))
2371 publickey_blob
= NULL
;
2373 publickey_blob
= NULL
;
2375 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
2376 static char password
[100];
2377 static char prompt
[200];
2380 static int pwpkt_type
;
2381 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2383 if (agent_exists() && !tried_agent
) {
2385 * Attempt RSA authentication using Pageant.
2387 static unsigned char request
[5], *response
, *p
;
2388 static int responselen
;
2389 static int i
, nkeys
;
2390 static int authed
= FALSE
;
2394 logevent("Pageant is running. Requesting keys.");
2396 /* Request the keys held by the agent. */
2397 PUT_32BIT(request
, 1);
2398 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2399 agent_query(request
, 5, &r
, &responselen
);
2400 response
= (unsigned char *) r
;
2401 if (response
&& responselen
>= 5 &&
2402 response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2404 nkeys
= GET_32BIT(p
);
2408 sprintf(buf
, "Pageant has %d SSH1 keys", nkeys
);
2411 for (i
= 0; i
< nkeys
; i
++) {
2412 static struct RSAKey key
;
2413 static Bignum challenge
;
2414 static char *commentp
;
2415 static int commentlen
;
2419 sprintf(buf
, "Trying Pageant key #%d", i
);
2422 if (publickey_blob
&&
2423 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
2424 logevent("This key matches configured key file");
2425 tried_publickey
= 1;
2428 p
+= ssh1_read_bignum(p
, &key
.exponent
);
2429 p
+= ssh1_read_bignum(p
, &key
.modulus
);
2430 commentlen
= GET_32BIT(p
);
2434 send_packet(SSH1_CMSG_AUTH_RSA
,
2435 PKT_BIGNUM
, key
.modulus
, PKT_END
);
2437 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2438 logevent("Key refused");
2441 logevent("Received RSA challenge");
2442 ssh1_read_bignum(pktin
.body
, &challenge
);
2444 char *agentreq
, *q
, *ret
;
2447 len
= 1 + 4; /* message type, bit count */
2448 len
+= ssh1_bignum_length(key
.exponent
);
2449 len
+= ssh1_bignum_length(key
.modulus
);
2450 len
+= ssh1_bignum_length(challenge
);
2451 len
+= 16; /* session id */
2452 len
+= 4; /* response format */
2453 agentreq
= smalloc(4 + len
);
2454 PUT_32BIT(agentreq
, len
);
2456 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2457 PUT_32BIT(q
, bignum_bitcount(key
.modulus
));
2459 q
+= ssh1_write_bignum(q
, key
.exponent
);
2460 q
+= ssh1_write_bignum(q
, key
.modulus
);
2461 q
+= ssh1_write_bignum(q
, challenge
);
2462 memcpy(q
, session_id
, 16);
2464 PUT_32BIT(q
, 1); /* response format */
2465 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2469 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2470 logevent("Sending Pageant's response");
2471 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2472 PKT_DATA
, ret
+ 5, 16,
2476 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2478 ("Pageant's response accepted");
2479 if (flags
& FLAG_VERBOSE
) {
2481 ("Authenticated using RSA key \"");
2482 c_write(commentp
, commentlen
);
2483 c_write_str("\" from agent\r\n");
2488 ("Pageant's response not accepted");
2491 ("Pageant failed to answer challenge");
2495 logevent("No reply received from Pageant");
2498 freebn(key
.exponent
);
2499 freebn(key
.modulus
);
2508 if (*cfg
.keyfile
&& !tried_publickey
)
2509 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2511 if (cfg
.try_tis_auth
&&
2512 (supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2513 !tis_auth_refused
) {
2514 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2515 logevent("Requested TIS authentication");
2516 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
2518 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2519 logevent("TIS authentication declined");
2520 if (flags
& FLAG_INTERACTIVE
)
2521 c_write_str("TIS authentication refused.\r\n");
2522 tis_auth_refused
= 1;
2525 int challengelen
= ((pktin
.body
[0] << 24) |
2526 (pktin
.body
[1] << 16) |
2527 (pktin
.body
[2] << 8) |
2529 logevent("Received TIS challenge");
2530 if (challengelen
> sizeof(prompt
) - 1)
2531 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2532 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2533 /* Prompt heuristic comes from OpenSSH */
2534 strncpy(prompt
+ challengelen
,
2535 memchr(prompt
, '\n', challengelen
) ?
2536 "": "\r\nResponse: ",
2537 (sizeof prompt
) - challengelen
);
2538 prompt
[(sizeof prompt
) - 1] = '\0';
2541 if (cfg
.try_tis_auth
&&
2542 (supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2543 !ccard_auth_refused
) {
2544 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2545 logevent("Requested CryptoCard authentication");
2546 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2548 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2549 logevent("CryptoCard authentication declined");
2550 c_write_str("CryptoCard authentication refused.\r\n");
2551 ccard_auth_refused
= 1;
2554 int challengelen
= ((pktin
.body
[0] << 24) |
2555 (pktin
.body
[1] << 16) |
2556 (pktin
.body
[2] << 8) |
2558 logevent("Received CryptoCard challenge");
2559 if (challengelen
> sizeof(prompt
) - 1)
2560 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2561 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2562 strncpy(prompt
+ challengelen
,
2563 memchr(prompt
, '\n', challengelen
) ?
2564 "" : "\r\nResponse: ",
2565 sizeof(prompt
) - challengelen
);
2566 prompt
[sizeof(prompt
) - 1] = '\0';
2569 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2570 sprintf(prompt
, "%.90s@%.90s's password: ",
2571 username
, savedhost
);
2573 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2574 char *comment
= NULL
;
2577 if (flags
& FLAG_VERBOSE
)
2578 c_write_str("Trying public key authentication.\r\n");
2579 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2581 type
= key_type(cfg
.keyfile
);
2582 if (type
!= SSH_KEYTYPE_SSH1
) {
2583 sprintf(msgbuf
, "Key is of wrong type (%s)",
2584 key_type_to_str(type
));
2586 c_write_str(msgbuf
);
2587 c_write_str("\r\n");
2588 tried_publickey
= 1;
2591 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2592 if (flags
& FLAG_VERBOSE
)
2593 c_write_str("No passphrase required.\r\n");
2596 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
2601 * Show password prompt, having first obtained it via a TIS
2602 * or CryptoCard exchange if we're doing TIS or CryptoCard
2606 if (!ssh_get_line(prompt
, password
, sizeof(password
), TRUE
)) {
2608 * get_line failed to get a password (for example
2609 * because one was supplied on the command line
2610 * which has already failed to work). Terminate.
2612 send_packet(SSH1_MSG_DISCONNECT
,
2613 PKT_STR
, "No more passwords available to try",
2615 logevent("Unable to authenticate");
2616 connection_fatal("Unable to authenticate");
2617 ssh_state
= SSH_STATE_CLOSED
;
2621 /* Prompt may have come from server. We've munged it a bit, so
2622 * we know it to be zero-terminated at least once. */
2624 c_write_untrusted(prompt
, strlen(prompt
));
2627 setup_userpass_input(password
, sizeof(password
), 0);
2629 crWaitUntil(!ispkt
);
2630 ret
= process_userpass_input(in
, inlen
);
2634 c_write_str("\r\n");
2638 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2640 * Try public key authentication with the specified
2643 static struct RSAKey pubkey
;
2644 static Bignum challenge
, response
;
2646 static unsigned char buffer
[32];
2648 tried_publickey
= 1;
2649 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
2651 c_write_str("Couldn't load private key from ");
2652 c_write_str(cfg
.keyfile
);
2653 c_write_str(".\r\n");
2654 continue; /* go and try password */
2657 c_write_str("Wrong passphrase.\r\n");
2658 tried_publickey
= 0;
2659 continue; /* try again */
2663 * Send a public key attempt.
2665 send_packet(SSH1_CMSG_AUTH_RSA
,
2666 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
2669 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2670 c_write_str("Server refused our public key.\r\n");
2671 continue; /* go and try password */
2673 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2674 bombout(("Bizarre response to offer of public key"));
2677 ssh1_read_bignum(pktin
.body
, &challenge
);
2678 response
= rsadecrypt(challenge
, &pubkey
);
2679 freebn(pubkey
.private_exponent
); /* burn the evidence */
2681 for (i
= 0; i
< 32; i
++) {
2682 buffer
[i
] = bignum_byte(response
, 31 - i
);
2686 MD5Update(&md5c
, buffer
, 32);
2687 MD5Update(&md5c
, session_id
, 16);
2688 MD5Final(buffer
, &md5c
);
2690 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2691 PKT_DATA
, buffer
, 16, PKT_END
);
2694 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2695 if (flags
& FLAG_VERBOSE
)
2697 ("Failed to authenticate with our public key.\r\n");
2698 continue; /* go and try password */
2699 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2701 ("Bizarre response to RSA authentication response"));
2705 break; /* we're through! */
2707 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2709 * Defence against traffic analysis: we send a
2710 * whole bunch of packets containing strings of
2711 * different lengths. One of these strings is the
2712 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2713 * The others are all random data in
2714 * SSH1_MSG_IGNORE packets. This way a passive
2715 * listener can't tell which is the password, and
2716 * hence can't deduce the password length.
2718 * Anybody with a password length greater than 16
2719 * bytes is going to have enough entropy in their
2720 * password that a listener won't find it _that_
2721 * much help to know how long it is. So what we'll
2724 * - if password length < 16, we send 15 packets
2725 * containing string lengths 1 through 15
2727 * - otherwise, we let N be the nearest multiple
2728 * of 8 below the password length, and send 8
2729 * packets containing string lengths N through
2730 * N+7. This won't obscure the order of
2731 * magnitude of the password length, but it will
2732 * introduce a bit of extra uncertainty.
2734 * A few servers (the old 1.2.18 through 1.2.22)
2735 * can't deal with SSH1_MSG_IGNORE. For these
2736 * servers, we need an alternative defence. We make
2737 * use of the fact that the password is interpreted
2738 * as a C string: so we can append a NUL, then some
2741 * One server (a Cisco one) can deal with neither
2742 * SSH1_MSG_IGNORE _nor_ a padded password string.
2743 * For this server we are left with no defences
2744 * against password length sniffing.
2746 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2748 * The server can deal with SSH1_MSG_IGNORE, so
2749 * we can use the primary defence.
2751 int bottom
, top
, pwlen
, i
;
2754 pwlen
= strlen(password
);
2756 bottom
= 0; /* zero length passwords are OK! :-) */
2759 bottom
= pwlen
& ~7;
2763 assert(pwlen
>= bottom
&& pwlen
<= top
);
2765 randomstr
= smalloc(top
+ 1);
2767 for (i
= bottom
; i
<= top
; i
++) {
2769 defer_packet(pwpkt_type
, PKT_STR
, password
,
2772 for (j
= 0; j
< i
; j
++) {
2774 randomstr
[j
] = random_byte();
2775 } while (randomstr
[j
] == '\0');
2777 randomstr
[i
] = '\0';
2778 defer_packet(SSH1_MSG_IGNORE
,
2779 PKT_STR
, randomstr
, PKT_END
);
2782 logevent("Sending password with camouflage packets");
2783 ssh_pkt_defersend();
2785 else if (!(ssh_remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2787 * The server can't deal with SSH1_MSG_IGNORE
2788 * but can deal with padded passwords, so we
2789 * can use the secondary defence.
2795 len
= strlen(password
);
2796 if (len
< sizeof(string
)) {
2798 strcpy(string
, password
);
2799 len
++; /* cover the zero byte */
2800 while (len
< sizeof(string
)) {
2801 string
[len
++] = (char) random_byte();
2806 logevent("Sending length-padded password");
2807 send_packet(pwpkt_type
, PKT_INT
, len
,
2808 PKT_DATA
, s
, len
, PKT_END
);
2811 * The server has _both_
2812 * BUG_CHOKES_ON_SSH1_IGNORE and
2813 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2814 * therefore nothing we can do.
2817 len
= strlen(password
);
2818 logevent("Sending unpadded password");
2819 send_packet(pwpkt_type
, PKT_INT
, len
,
2820 PKT_DATA
, password
, len
, PKT_END
);
2823 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
2826 logevent("Sent password");
2827 memset(password
, 0, strlen(password
));
2829 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2830 if (flags
& FLAG_VERBOSE
)
2831 c_write_str("Access denied\r\n");
2832 logevent("Authentication refused");
2833 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2834 logevent("Received disconnect request");
2835 ssh_state
= SSH_STATE_CLOSED
;
2837 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2838 bombout(("Strange packet received, type %d", pktin
.type
));
2843 logevent("Authentication successful");
2848 void sshfwd_close(struct ssh_channel
*c
)
2850 if (c
&& !c
->closes
) {
2852 * If the channel's remoteid is -1, we have sent
2853 * CHANNEL_OPEN for this channel, but it hasn't even been
2854 * acknowledged by the server. So we must set a close flag
2855 * on it now, and then when the server acks the channel
2856 * open, we can close it then.
2858 if (((int)c
->remoteid
) != -1) {
2859 if (ssh_version
== 1) {
2860 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2863 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2864 ssh2_pkt_adduint32(c
->remoteid
);
2869 if (c
->type
== CHAN_X11
) {
2871 logevent("Forwarded X11 connection terminated");
2872 } else if (c
->type
== CHAN_SOCKDATA
||
2873 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2875 logevent("Forwarded port closed");
2880 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2882 if (ssh_version
== 1) {
2883 send_packet(SSH1_MSG_CHANNEL_DATA
,
2884 PKT_INT
, c
->remoteid
,
2885 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2887 * In SSH1 we can return 0 here - implying that forwarded
2888 * connections are never individually throttled - because
2889 * the only circumstance that can cause throttling will be
2890 * the whole SSH connection backing up, in which case
2891 * _everything_ will be throttled as a whole.
2895 ssh2_add_channel_data(c
, buf
, len
);
2896 return ssh2_try_send(c
);
2900 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2902 if (ssh_version
== 1) {
2903 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2904 c
->v
.v1
.throttling
= 0;
2908 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
2912 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
)
2918 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
2921 if (ssh_state
== SSH_STATE_CLOSED
)
2924 if (cfg
.agentfwd
&& agent_exists()) {
2925 logevent("Requesting agent forwarding");
2926 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
2930 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2931 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2932 bombout(("Protocol confusion"));
2934 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2935 logevent("Agent forwarding refused");
2937 logevent("Agent forwarding enabled");
2938 ssh_agentfwd_enabled
= TRUE
;
2942 if (cfg
.x11_forward
) {
2943 char proto
[20], data
[64];
2944 logevent("Requesting X11 forwarding");
2945 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2946 if (ssh1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
2947 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2948 PKT_STR
, proto
, PKT_STR
, data
,
2949 PKT_INT
, 0, PKT_END
);
2951 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2952 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
2957 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2958 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2959 bombout(("Protocol confusion"));
2961 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2962 logevent("X11 forwarding refused");
2964 logevent("X11 forwarding enabled");
2965 ssh_X11_fwd_enabled
= TRUE
;
2973 int sport
,dport
,sserv
,dserv
;
2974 char sports
[256], dports
[256], host
[256];
2978 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh1
);
2979 /* Add port forwardings. */
2984 while (*e
&& *e
!= '\t')
2990 while (*e
&& *e
!= ':')
3000 dport
= atoi(dports
);
3004 se
= getservbyname(dports
, NULL
);
3006 dport
= ntohs(se
->s_port
);
3009 "Service lookup failed for destination port \"%s\"",
3014 sport
= atoi(sports
);
3018 se
= getservbyname(sports
, NULL
);
3020 sport
= ntohs(se
->s_port
);
3023 "Service lookup failed for source port \"%s\"",
3028 if (sport
&& dport
) {
3030 pfd_addforward(host
, dport
, sport
);
3031 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3032 " %s:%.*s%.*s%d%.*s",
3033 sserv ?
strlen(sports
) : 0, sports
,
3034 sserv
, "(", sport
, sserv
, ")",
3036 dserv ?
strlen(dports
) : 0, dports
,
3037 dserv
, "(", dport
, dserv
, ")");
3040 struct ssh_rportfwd
*pf
;
3041 pf
= smalloc(sizeof(*pf
));
3042 strcpy(pf
->dhost
, host
);
3044 if (add234(ssh_rportfwds
, pf
) != pf
) {
3046 "Duplicate remote port forwarding to %s:%d",
3051 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3052 " forward to %s:%.*s%.*s%d%.*s",
3053 sserv ?
strlen(sports
) : 0, sports
,
3054 sserv
, "(", sport
, sserv
, ")",
3056 dserv ?
strlen(dports
) : 0, dports
,
3057 dserv
, "(", dport
, dserv
, ")");
3059 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST
,
3067 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3068 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3069 bombout(("Protocol confusion"));
3071 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3072 c_write_str("Server refused port forwarding\r\n");
3073 ssh_editing
= ssh_echoing
= 1;
3075 logevent("Remote port forwarding enabled");
3083 send_packet(SSH1_CMSG_REQUEST_PTY
,
3084 PKT_STR
, cfg
.termtype
,
3085 PKT_INT
, rows
, PKT_INT
, cols
,
3086 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3087 ssh_state
= SSH_STATE_INTERMED
;
3091 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3092 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3093 bombout(("Protocol confusion"));
3095 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3096 c_write_str("Server refused to allocate pty\r\n");
3097 ssh_editing
= ssh_echoing
= 1;
3099 logevent("Allocated pty");
3101 ssh_editing
= ssh_echoing
= 1;
3104 if (cfg
.compression
) {
3105 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3109 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3110 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3111 bombout(("Protocol confusion"));
3113 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3114 c_write_str("Server refused to compress\r\n");
3116 logevent("Started compression");
3117 ssh1_compressing
= TRUE
;
3118 zlib_compress_init();
3119 zlib_decompress_init();
3123 * Start the shell or command.
3125 * Special case: if the first-choice command is an SSH2
3126 * subsystem (hence not usable here) and the second choice
3127 * exists, we fall straight back to that.
3130 char *cmd
= cfg
.remote_cmd_ptr
;
3132 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3133 cmd
= cfg
.remote_cmd_ptr2
;
3134 ssh_fallback_cmd
= TRUE
;
3137 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3139 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3140 logevent("Started session");
3143 ssh_state
= SSH_STATE_SESSION
;
3147 ssh_special(TS_EOF
);
3149 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
3151 ssh_channels
= newtree234(ssh_channelcmp
);
3155 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3156 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3157 long len
= GET_32BIT(pktin
.body
);
3159 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3160 pktin
.body
+ 4, len
);
3161 if (!ssh1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3162 ssh1_stdout_throttling
= 1;
3165 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
3166 ssh_state
= SSH_STATE_CLOSED
;
3167 logevent("Received disconnect request");
3169 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3170 /* Remote side is trying to open a channel to talk to our
3171 * X-Server. Give them back a local channel number. */
3172 struct ssh_channel
*c
;
3174 logevent("Received X11 connect request");
3175 /* Refuse if X11 forwarding is disabled. */
3176 if (!ssh_X11_fwd_enabled
) {
3177 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3178 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3179 logevent("Rejected X11 connect request");
3181 c
= smalloc(sizeof(struct ssh_channel
));
3183 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3184 logevent("opening X11 forward connection failed");
3186 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3187 PKT_INT
, GET_32BIT(pktin
.body
),
3191 ("opening X11 forward connection succeeded");
3192 c
->remoteid
= GET_32BIT(pktin
.body
);
3193 c
->localid
= alloc_channel_id();
3195 c
->v
.v1
.throttling
= 0;
3196 c
->type
= CHAN_X11
; /* identify channel type */
3197 add234(ssh_channels
, c
);
3198 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3199 PKT_INT
, c
->remoteid
, PKT_INT
,
3200 c
->localid
, PKT_END
);
3201 logevent("Opened X11 forward channel");
3204 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3205 /* Remote side is trying to open a channel to talk to our
3206 * agent. Give them back a local channel number. */
3207 struct ssh_channel
*c
;
3209 /* Refuse if agent forwarding is disabled. */
3210 if (!ssh_agentfwd_enabled
) {
3211 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3212 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3214 c
= smalloc(sizeof(struct ssh_channel
));
3215 c
->remoteid
= GET_32BIT(pktin
.body
);
3216 c
->localid
= alloc_channel_id();
3218 c
->v
.v1
.throttling
= 0;
3219 c
->type
= CHAN_AGENT
; /* identify channel type */
3220 c
->u
.a
.lensofar
= 0;
3221 add234(ssh_channels
, c
);
3222 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3223 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3226 } else if (pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3227 /* Remote side is trying to open a channel to talk to a
3228 * forwarded port. Give them back a local channel number. */
3229 struct ssh_channel
*c
;
3230 struct ssh_rportfwd pf
;
3232 char host
[256], buf
[1024];
3234 c
= smalloc(sizeof(struct ssh_channel
));
3236 hostsize
= GET_32BIT(pktin
.body
+4);
3237 for(h
= host
, p
= pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3238 if (h
+1 < host
+sizeof(host
))
3243 port
= GET_32BIT(p
);
3245 strcpy(pf
.dhost
, host
);
3248 if (find234(ssh_rportfwds
, &pf
, NULL
) == NULL
) {
3249 sprintf(buf
, "Rejected remote port open request for %s:%d",
3252 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3253 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3255 sprintf(buf
, "Received remote port open request for %s:%d",
3258 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3261 sprintf(buf
, "Port open failed: %s", e
);
3264 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3265 PKT_INT
, GET_32BIT(pktin
.body
),
3268 c
->remoteid
= GET_32BIT(pktin
.body
);
3269 c
->localid
= alloc_channel_id();
3271 c
->v
.v1
.throttling
= 0;
3272 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3273 add234(ssh_channels
, c
);
3274 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3275 PKT_INT
, c
->remoteid
, PKT_INT
,
3276 c
->localid
, PKT_END
);
3277 logevent("Forwarded port opened successfully");
3281 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3282 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3283 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3284 struct ssh_channel
*c
;
3286 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3287 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3288 c
->remoteid
= localid
;
3289 c
->type
= CHAN_SOCKDATA
;
3290 c
->v
.v1
.throttling
= 0;
3291 pfd_confirm(c
->u
.pfd
.s
);
3294 if (c
&& c
->closes
) {
3296 * We have a pending close on this channel,
3297 * which we decided on before the server acked
3298 * the channel open. So now we know the
3299 * remoteid, we can close it again.
3301 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3305 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3306 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3307 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3308 struct ssh_channel
*c
;
3310 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3311 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3312 logevent("Forwarded connection refused by server");
3313 pfd_close(c
->u
.pfd
.s
);
3314 del234(ssh_channels
, c
);
3318 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3319 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3320 /* Remote side closes a channel. */
3321 unsigned i
= GET_32BIT(pktin
.body
);
3322 struct ssh_channel
*c
;
3323 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3327 (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3328 if (!(c
->closes
& closetype
))
3329 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
,
3331 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3332 logevent("Forwarded X11 connection terminated");
3333 assert(c
->u
.x11
.s
!= NULL
);
3334 x11_close(c
->u
.x11
.s
);
3337 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3338 logevent("Forwarded port closed");
3339 assert(c
->u
.pfd
.s
!= NULL
);
3340 pfd_close(c
->u
.pfd
.s
);
3343 c
->closes
|= closetype
;
3344 if (c
->closes
== 3) {
3345 del234(ssh_channels
, c
);
3349 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3350 /* Data sent down one of our channels. */
3351 int i
= GET_32BIT(pktin
.body
);
3352 int len
= GET_32BIT(pktin
.body
+ 4);
3353 unsigned char *p
= pktin
.body
+ 8;
3354 struct ssh_channel
*c
;
3355 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3360 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3363 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3366 /* Data for an agent message. Buffer it. */
3368 if (c
->u
.a
.lensofar
< 4) {
3369 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3370 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3374 c
->u
.a
.lensofar
+= l
;
3376 if (c
->u
.a
.lensofar
== 4) {
3378 4 + GET_32BIT(c
->u
.a
.msglen
);
3379 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3380 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3382 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3384 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3386 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3390 c
->u
.a
.lensofar
+= l
;
3392 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3393 void *reply
, *sentreply
;
3395 agent_query(c
->u
.a
.message
,
3396 c
->u
.a
.totallen
, &reply
,
3401 /* Fake SSH_AGENT_FAILURE. */
3402 sentreply
= "\0\0\0\1\5";
3405 send_packet(SSH1_MSG_CHANNEL_DATA
,
3406 PKT_INT
, c
->remoteid
,
3408 PKT_DATA
, sentreply
, replylen
,
3412 sfree(c
->u
.a
.message
);
3413 c
->u
.a
.lensofar
= 0;
3416 bufsize
= 0; /* agent channels never back up */
3419 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3420 c
->v
.v1
.throttling
= 1;
3424 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
3425 /* may be from EXEC_SHELL on some servers */
3426 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3427 /* may be from EXEC_SHELL on some servers
3428 * if no pty is available or in other odd cases. Ignore */
3429 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3431 ssh_exitcode
= GET_32BIT(pktin
.body
);
3432 sprintf(buf
, "Server sent command exit status %d",
3435 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3437 * In case `helpful' firewalls or proxies tack
3438 * extra human-readable text on the end of the
3439 * session which we might mistake for another
3440 * encrypted packet, we close the session once
3441 * we've sent EXIT_CONFIRMATION.
3443 ssh_state
= SSH_STATE_CLOSED
;
3446 bombout(("Strange packet received: type %d", pktin
.type
));
3451 int len
= min(inlen
, 512);
3452 send_packet(SSH1_CMSG_STDIN_DATA
,
3453 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3464 * Utility routine for decoding comma-separated strings in KEXINIT.
3466 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3468 int needlen
= strlen(needle
);
3471 * Is it at the start of the string?
3473 if (haylen
>= needlen
&& /* haystack is long enough */
3474 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3475 (haylen
== needlen
|| haystack
[needlen
] == ',')
3476 /* either , or EOS follows */
3480 * If not, search for the next comma and resume after that.
3481 * If no comma found, terminate.
3483 while (haylen
> 0 && *haystack
!= ',')
3484 haylen
--, haystack
++;
3487 haylen
--, haystack
++; /* skip over comma itself */
3492 * SSH2 key creation method.
3494 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
,
3498 /* First 20 bytes. */
3501 SHA_Bytes(&s
, H
, 20);
3502 SHA_Bytes(&s
, &chr
, 1);
3503 SHA_Bytes(&s
, sessid
, 20);
3504 SHA_Final(&s
, keyspace
);
3505 /* Next 20 bytes. */
3508 SHA_Bytes(&s
, H
, 20);
3509 SHA_Bytes(&s
, keyspace
, 20);
3510 SHA_Final(&s
, keyspace
+ 20);
3514 * Handle the SSH2 transport layer.
3516 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
3518 static int i
, j
, len
, nbits
, pbits
, warn
;
3520 static Bignum p
, g
, e
, f
, K
;
3521 static int kex_init_value
, kex_reply_value
;
3522 static const struct ssh_mac
**maclist
;
3524 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
3525 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
3526 static const struct ssh_mac
*csmac_tobe
= NULL
;
3527 static const struct ssh_mac
*scmac_tobe
= NULL
;
3528 static const struct ssh_compress
*cscomp_tobe
= NULL
;
3529 static const struct ssh_compress
*sccomp_tobe
= NULL
;
3530 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3531 static int hostkeylen
, siglen
;
3532 static void *hkey
; /* actual host key */
3533 static unsigned char exchange_hash
[20];
3534 static unsigned char keyspace
[40];
3535 static int n_preferred_ciphers
;
3536 static const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3537 static const struct ssh_compress
*preferred_comp
;
3538 static int cipherstr_started
;
3539 static int first_kex
;
3546 * Set up the preferred ciphers. (NULL => warn below here)
3548 n_preferred_ciphers
= 0;
3549 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3550 switch (cfg
.ssh_cipherlist
[i
]) {
3551 case CIPHER_BLOWFISH
:
3552 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_blowfish
;
3553 n_preferred_ciphers
++;
3556 if (cfg
.ssh2_des_cbc
) {
3557 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_des
;
3558 n_preferred_ciphers
++;
3562 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_3des
;
3563 n_preferred_ciphers
++;
3566 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_aes
;
3567 n_preferred_ciphers
++;
3570 /* Flag for later. Don't bother if it's the last in
3572 if (i
< CIPHER_MAX
- 1) {
3573 preferred_ciphers
[n_preferred_ciphers
] = NULL
;
3574 n_preferred_ciphers
++;
3581 * Set up preferred compression.
3583 if (cfg
.compression
)
3584 preferred_comp
= &ssh_zlib
;
3586 preferred_comp
= &ssh_comp_none
;
3589 * Be prepared to work around the buggy MAC problem.
3591 if (cfg
.buggymac
|| (ssh_remote_bugs
& BUG_SSH2_HMAC
))
3592 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
3594 maclist
= macs
, nmacs
= lenof(macs
);
3598 * Construct and send our key exchange packet.
3600 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
3601 for (i
= 0; i
< 16; i
++)
3602 ssh2_pkt_addbyte((unsigned char) random_byte());
3603 /* List key exchange algorithms. */
3604 ssh2_pkt_addstring_start();
3605 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3606 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
3607 if (i
< lenof(kex_algs
) - 1)
3608 ssh2_pkt_addstring_str(",");
3610 /* List server host key algorithms. */
3611 ssh2_pkt_addstring_start();
3612 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3613 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
3614 if (i
< lenof(hostkey_algs
) - 1)
3615 ssh2_pkt_addstring_str(",");
3617 /* List client->server encryption algorithms. */
3618 ssh2_pkt_addstring_start();
3619 cipherstr_started
= 0;
3620 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3621 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3622 if (!c
) continue; /* warning flag */
3623 for (j
= 0; j
< c
->nciphers
; j
++) {
3624 if (cipherstr_started
)
3625 ssh2_pkt_addstring_str(",");
3626 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3627 cipherstr_started
= 1;
3630 /* List server->client 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 client->server MAC algorithms. */
3644 ssh2_pkt_addstring_start();
3645 for (i
= 0; i
< nmacs
; i
++) {
3646 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3648 ssh2_pkt_addstring_str(",");
3650 /* List server->client MAC algorithms. */
3651 ssh2_pkt_addstring_start();
3652 for (i
= 0; i
< nmacs
; i
++) {
3653 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3655 ssh2_pkt_addstring_str(",");
3657 /* List client->server compression algorithms. */
3658 ssh2_pkt_addstring_start();
3659 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3660 const struct ssh_compress
*c
=
3661 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3662 ssh2_pkt_addstring_str(c
->name
);
3663 if (i
< lenof(compressions
))
3664 ssh2_pkt_addstring_str(",");
3666 /* List server->client compression algorithms. */
3667 ssh2_pkt_addstring_start();
3668 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3669 const struct ssh_compress
*c
=
3670 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3671 ssh2_pkt_addstring_str(c
->name
);
3672 if (i
< lenof(compressions
))
3673 ssh2_pkt_addstring_str(",");
3675 /* List client->server languages. Empty list. */
3676 ssh2_pkt_addstring_start();
3677 /* List server->client languages. Empty list. */
3678 ssh2_pkt_addstring_start();
3679 /* First KEX packet does _not_ follow, because we're not that brave. */
3680 ssh2_pkt_addbool(FALSE
);
3682 ssh2_pkt_adduint32(0);
3684 exhash
= exhashbase
;
3685 sha_string(&exhash
, pktout
.data
+ 5, pktout
.length
- 5);
3691 sha_string(&exhash
, pktin
.data
+ 5, pktin
.length
- 5);
3694 * Now examine the other side's KEXINIT to see what we're up
3697 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
3698 bombout(("expected key exchange packet from server"));
3703 cscipher_tobe
= NULL
;
3704 sccipher_tobe
= NULL
;
3709 pktin
.savedpos
+= 16; /* skip garbage cookie */
3710 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
3711 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3712 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3717 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
3718 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3719 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3720 hostkey
= hostkey_algs
[i
];
3724 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
3726 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3727 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3731 for (j
= 0; j
< c
->nciphers
; j
++) {
3732 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3733 cscipher_tobe
= c
->list
[j
];
3738 if (cscipher_tobe
) {
3740 askcipher(cscipher_tobe
->name
, 1);
3744 if (!cscipher_tobe
) {
3745 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3749 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
3751 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3752 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3756 for (j
= 0; j
< c
->nciphers
; j
++) {
3757 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3758 sccipher_tobe
= c
->list
[j
];
3763 if (sccipher_tobe
) {
3765 askcipher(sccipher_tobe
->name
, 2);
3769 if (!sccipher_tobe
) {
3770 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3774 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
3775 for (i
= 0; i
< nmacs
; i
++) {
3776 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3777 csmac_tobe
= maclist
[i
];
3781 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
3782 for (i
= 0; i
< nmacs
; i
++) {
3783 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3784 scmac_tobe
= maclist
[i
];
3788 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
3789 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3790 const struct ssh_compress
*c
=
3791 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3792 if (in_commasep_string(c
->name
, str
, len
)) {
3797 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
3798 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3799 const struct ssh_compress
*c
=
3800 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3801 if (in_commasep_string(c
->name
, str
, len
)) {
3808 * Work out the number of bits of key we will need from the key
3809 * exchange. We start with the maximum key length of either
3815 csbits
= cscipher_tobe
->keylen
;
3816 scbits
= sccipher_tobe
->keylen
;
3817 nbits
= (csbits
> scbits ? csbits
: scbits
);
3819 /* The keys only have 160-bit entropy, since they're based on
3820 * a SHA-1 hash. So cap the key size at 160 bits. */
3825 * If we're doing Diffie-Hellman group exchange, start by
3826 * requesting a group.
3828 if (kex
== &ssh_diffiehellman_gex
) {
3829 logevent("Doing Diffie-Hellman group exchange");
3830 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3832 * Work out how big a DH group we will need to allow that
3835 pbits
= 512 << ((nbits
- 1) / 64);
3836 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
3837 ssh2_pkt_adduint32(pbits
);
3841 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3842 bombout(("expected key exchange group packet from server"));
3845 p
= ssh2_pkt_getmp();
3846 g
= ssh2_pkt_getmp();
3847 dh_setup_group(p
, g
);
3848 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3849 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3851 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3853 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3854 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3857 logevent("Doing Diffie-Hellman key exchange");
3859 * Now generate and send e for Diffie-Hellman.
3861 e
= dh_create_e(nbits
* 2);
3862 ssh2_pkt_init(kex_init_value
);
3867 if (pktin
.type
!= kex_reply_value
) {
3868 bombout(("expected key exchange reply packet from server"));
3871 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
3872 f
= ssh2_pkt_getmp();
3873 ssh2_pkt_getstring(&sigdata
, &siglen
);
3877 sha_string(&exhash
, hostkeydata
, hostkeylen
);
3878 if (kex
== &ssh_diffiehellman_gex
) {
3879 sha_uint32(&exhash
, pbits
);
3880 sha_mpint(&exhash
, p
);
3881 sha_mpint(&exhash
, g
);
3883 sha_mpint(&exhash
, e
);
3884 sha_mpint(&exhash
, f
);
3885 sha_mpint(&exhash
, K
);
3886 SHA_Final(&exhash
, exchange_hash
);
3891 debug(("Exchange hash is:\n"));
3892 dmemdump(exchange_hash
, 20);
3895 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
3897 !hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
3898 bombout(("Server's host key did not match the signature supplied"));
3903 * Authenticate remote host: verify host key. (We've already
3904 * checked the signature of the exchange hash.)
3906 keystr
= hostkey
->fmtkey(hkey
);
3907 fingerprint
= hostkey
->fingerprint(hkey
);
3908 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
3909 keystr
, fingerprint
);
3910 if (first_kex
) { /* don't bother logging this in rekeys */
3911 logevent("Host key fingerprint is:");
3912 logevent(fingerprint
);
3916 hostkey
->freekey(hkey
);
3919 * Send SSH2_MSG_NEWKEYS.
3921 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
3925 * Expect SSH2_MSG_NEWKEYS from server.
3928 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
3929 bombout(("expected new-keys packet from server"));
3934 * Create and initialise session keys.
3936 cscipher
= cscipher_tobe
;
3937 sccipher
= sccipher_tobe
;
3940 cscomp
= cscomp_tobe
;
3941 sccomp
= sccomp_tobe
;
3942 cscomp
->compress_init();
3943 sccomp
->decompress_init();
3945 * Set IVs after keys. Here we use the exchange hash from the
3946 * _first_ key exchange.
3949 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
3950 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
3951 cscipher
->setcskey(keyspace
);
3952 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
3953 sccipher
->setsckey(keyspace
);
3954 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
3955 cscipher
->setcsiv(keyspace
);
3956 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
3957 sccipher
->setsciv(keyspace
);
3958 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
3959 csmac
->setcskey(keyspace
);
3960 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
3961 scmac
->setsckey(keyspace
);
3964 * If this is the first key exchange phase, we must pass the
3965 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
3966 * wants to see it but because it will need time to initialise
3967 * itself before it sees an actual packet. In subsequent key
3968 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
3969 * it would only confuse the layer above.
3977 * Now we're encrypting. Begin returning 1 to the protocol main
3978 * function so that other things can run on top of the
3979 * transport. If we ever see a KEXINIT, we must go back to the
3982 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
3985 logevent("Server initiated key re-exchange");
3986 goto begin_key_exchange
;
3992 * Add data to an SSH2 channel output buffer.
3994 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
3997 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4001 * Attempt to send data on an SSH2 channel.
4003 static int ssh2_try_send(struct ssh_channel
*c
)
4005 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4008 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4009 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4010 len
= c
->v
.v2
.remwindow
;
4011 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4012 len
= c
->v
.v2
.remmaxpkt
;
4013 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4014 ssh2_pkt_adduint32(c
->remoteid
);
4015 ssh2_pkt_addstring_start();
4016 ssh2_pkt_addstring_data(data
, len
);
4018 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4019 c
->v
.v2
.remwindow
-= len
;
4023 * After having sent as much data as we can, return the amount
4026 return bufchain_size(&c
->v
.v2
.outbuffer
);
4030 * Potentially enlarge the window on an SSH2 channel.
4032 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4035 * Never send WINDOW_ADJUST for a channel that the remote side
4036 * already thinks it's closed; there's no point, since it won't
4037 * be sending any more data anyway.
4042 if (newwin
> c
->v
.v2
.locwindow
) {
4043 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4044 ssh2_pkt_adduint32(c
->remoteid
);
4045 ssh2_pkt_adduint32(newwin
- c
->v
.v2
.locwindow
);
4047 c
->v
.v2
.locwindow
= newwin
;
4052 * Handle the SSH2 userauth and connection layers.
4054 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
4057 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4059 AUTH_KEYBOARD_INTERACTIVE
4063 AUTH_TYPE_PUBLICKEY
,
4064 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4065 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4067 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4068 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4070 static int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4071 static int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4072 static int kbd_inter_running
;
4073 static int we_are_in
;
4074 static int num_prompts
, curr_prompt
, echo
;
4075 static char username
[100];
4076 static int got_username
;
4077 static char pwprompt
[200];
4078 static char password
[100];
4079 static void *publickey_blob
;
4080 static int publickey_bloblen
;
4085 * Request userauth protocol, and await a response to it.
4087 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
4088 ssh2_pkt_addstring("ssh-userauth");
4090 crWaitUntilV(ispkt
);
4091 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4092 bombout(("Server refused user authentication protocol"));
4097 * We repeat this whole loop, including the username prompt,
4098 * until we manage a successful authentication. If the user
4099 * types the wrong _password_, they are sent back to the
4100 * beginning to try another username. (If they specify a
4101 * username in the config, they are never asked, even if they
4102 * do give a wrong password.)
4104 * I think this best serves the needs of
4106 * - the people who have no configuration, no keys, and just
4107 * want to try repeated (username,password) pairs until they
4108 * type both correctly
4110 * - people who have keys and configuration but occasionally
4111 * need to fall back to passwords
4113 * - people with a key held in Pageant, who might not have
4114 * logged in to a particular machine before; so they want to
4115 * type a username, and then _either_ their key will be
4116 * accepted, _or_ they will type a password. If they mistype
4117 * the username they will want to be able to get back and
4121 got_username
= FALSE
;
4126 if (got_username
&& !cfg
.change_username
) {
4128 * We got a username last time round this loop, and
4129 * with change_username turned off we don't try to get
4132 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4133 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4134 if (!ssh_get_line("login as: ",
4135 username
, sizeof(username
), FALSE
)) {
4137 * get_line failed to get a username.
4140 logevent("No username provided. Abandoning session.");
4141 ssh_state
= SSH_STATE_CLOSED
;
4146 c_write_str("login as: ");
4148 setup_userpass_input(username
, sizeof(username
), 1);
4150 crWaitUntilV(!ispkt
);
4151 ret
= process_userpass_input(in
, inlen
);
4156 c_write_str("\r\n");
4157 username
[strcspn(username
, "\n\r")] = '\0';
4160 strncpy(username
, cfg
.username
, 99);
4161 username
[99] = '\0';
4162 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4163 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
4167 got_username
= TRUE
;
4170 * Send an authentication request using method "none": (a)
4171 * just in case it succeeds, and (b) so that we know what
4172 * authentication methods we can usefully try next.
4174 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4176 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4177 ssh2_pkt_addstring(username
);
4178 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4179 ssh2_pkt_addstring("none"); /* method */
4181 type
= AUTH_TYPE_NONE
;
4185 tried_pubkey_config
= FALSE
;
4186 tried_agent
= FALSE
;
4187 tried_keyb_inter
= FALSE
;
4188 kbd_inter_running
= FALSE
;
4189 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4192 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4193 keytype
= key_type(cfg
.keyfile
);
4194 if (keytype
== SSH_KEYTYPE_SSH2
)
4195 publickey_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4196 &publickey_bloblen
);
4199 logeventf("Unable to use this key file (%s)",
4200 key_type_to_str(keytype
));
4201 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4202 cfg
.keyfile
, key_type_to_str(keytype
));
4203 c_write_str(msgbuf
);
4204 publickey_blob
= NULL
;
4207 publickey_blob
= NULL
;
4211 * Wait for the result of the last authentication request.
4214 crWaitUntilV(ispkt
);
4215 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4219 * Don't show the banner if we're operating in
4220 * non-verbose non-interactive mode. (It's probably
4221 * a script, which means nobody will read the
4222 * banner _anyway_, and moreover the printing of
4223 * the banner will screw up processing on the
4224 * output of (say) plink.)
4226 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4227 ssh2_pkt_getstring(&banner
, &size
);
4229 c_write_untrusted(banner
, size
);
4231 crWaitUntilV(ispkt
);
4233 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4234 logevent("Access granted");
4239 if (kbd_inter_running
&&
4240 pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4242 * This is either a further set-of-prompts packet
4243 * in keyboard-interactive authentication, or it's
4244 * the same one and we came back here with `gotit'
4245 * set. In the former case, we must reset the
4246 * curr_prompt variable.
4250 } else if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4251 bombout(("Strange packet received during authentication: type %d",
4259 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4260 * we can look at the string in it and know what we can
4261 * helpfully try next.
4263 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4266 ssh2_pkt_getstring(&methods
, &methlen
);
4267 kbd_inter_running
= FALSE
;
4268 if (!ssh2_pkt_getbool()) {
4270 * We have received an unequivocal Access
4271 * Denied. This can translate to a variety of
4274 * - if we'd just tried "none" authentication,
4275 * it's not worth printing anything at all
4277 * - if we'd just tried a public key _offer_,
4278 * the message should be "Server refused our
4279 * key" (or no message at all if the key
4280 * came from Pageant)
4282 * - if we'd just tried anything else, the
4283 * message really should be "Access denied".
4285 * Additionally, if we'd just tried password
4286 * authentication, we should break out of this
4287 * whole loop so as to go back to the username
4290 if (type
== AUTH_TYPE_NONE
) {
4292 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4293 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4294 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4295 c_write_str("Server refused our key\r\n");
4296 logevent("Server refused public key");
4297 } else if (type
== AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4298 /* server declined keyboard-interactive; ignore */
4300 c_write_str("Access denied\r\n");
4301 logevent("Access denied");
4302 if (type
== AUTH_TYPE_PASSWORD
) {
4308 c_write_str("Further authentication required\r\n");
4309 logevent("Further authentication required");
4313 in_commasep_string("publickey", methods
, methlen
);
4315 in_commasep_string("password", methods
, methlen
);
4316 can_keyb_inter
= cfg
.try_ki_auth
&&
4317 in_commasep_string("keyboard-interactive", methods
, methlen
);
4321 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4324 * Most password/passphrase prompts will be
4325 * non-echoing, so we set this to 0 by default.
4326 * Exception is that some keyboard-interactive prompts
4327 * can be echoing, in which case we'll set this to 1.
4331 if (!method
&& can_pubkey
&& agent_exists() && !tried_agent
) {
4333 * Attempt public-key authentication using Pageant.
4335 static unsigned char request
[5], *response
, *p
;
4336 static int responselen
;
4337 static int i
, nkeys
;
4338 static int authed
= FALSE
;
4341 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4342 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4346 logevent("Pageant is running. Requesting keys.");
4348 /* Request the keys held by the agent. */
4349 PUT_32BIT(request
, 1);
4350 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4351 agent_query(request
, 5, &r
, &responselen
);
4352 response
= (unsigned char *) r
;
4353 if (response
&& responselen
>= 5 &&
4354 response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4356 nkeys
= GET_32BIT(p
);
4360 sprintf(buf
, "Pageant has %d SSH2 keys", nkeys
);
4363 for (i
= 0; i
< nkeys
; i
++) {
4364 static char *pkblob
, *alg
, *commentp
;
4365 static int pklen
, alglen
, commentlen
;
4366 static int siglen
, retlen
, len
;
4367 static char *q
, *agentreq
, *ret
;
4372 sprintf(buf
, "Trying Pageant key #%d", i
);
4375 pklen
= GET_32BIT(p
);
4377 if (publickey_blob
&&
4378 pklen
== publickey_bloblen
&&
4379 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
4380 logevent("This key matches configured key file");
4381 tried_pubkey_config
= 1;
4385 alglen
= GET_32BIT(pkblob
);
4387 commentlen
= GET_32BIT(p
);
4391 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4392 ssh2_pkt_addstring(username
);
4393 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4394 ssh2_pkt_addstring("publickey"); /* method */
4395 ssh2_pkt_addbool(FALSE
); /* no signature included */
4396 ssh2_pkt_addstring_start();
4397 ssh2_pkt_addstring_data(alg
, alglen
);
4398 ssh2_pkt_addstring_start();
4399 ssh2_pkt_addstring_data(pkblob
, pklen
);
4402 crWaitUntilV(ispkt
);
4403 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4404 logevent("Key refused");
4408 if (flags
& FLAG_VERBOSE
) {
4410 ("Authenticating with public key \"");
4411 c_write(commentp
, commentlen
);
4412 c_write_str("\" from agent\r\n");
4416 * Server is willing to accept the key.
4417 * Construct a SIGN_REQUEST.
4419 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4420 ssh2_pkt_addstring(username
);
4421 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4422 ssh2_pkt_addstring("publickey"); /* method */
4423 ssh2_pkt_addbool(TRUE
);
4424 ssh2_pkt_addstring_start();
4425 ssh2_pkt_addstring_data(alg
, alglen
);
4426 ssh2_pkt_addstring_start();
4427 ssh2_pkt_addstring_data(pkblob
, pklen
);
4429 siglen
= pktout
.length
- 5 + 4 + 20;
4430 len
= 1; /* message type */
4431 len
+= 4 + pklen
; /* key blob */
4432 len
+= 4 + siglen
; /* data to sign */
4433 len
+= 4; /* flags */
4434 agentreq
= smalloc(4 + len
);
4435 PUT_32BIT(agentreq
, len
);
4437 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4438 PUT_32BIT(q
, pklen
);
4440 memcpy(q
, pkblob
, pklen
);
4442 PUT_32BIT(q
, siglen
);
4444 /* Now the data to be signed... */
4447 memcpy(q
, ssh2_session_id
, 20);
4449 memcpy(q
, pktout
.data
+ 5, pktout
.length
- 5);
4450 q
+= pktout
.length
- 5;
4451 /* And finally the (zero) flags word. */
4453 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
4457 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4458 logevent("Sending Pageant's response");
4459 ssh2_add_sigblob(pkblob
, pklen
,
4460 ret
+ 9, GET_32BIT(ret
+ 5));
4466 ("Pageant failed to answer challenge");
4476 if (!method
&& can_pubkey
&& publickey_blob
4477 && !tried_pubkey_config
) {
4478 unsigned char *pub_blob
;
4479 char *algorithm
, *comment
;
4482 tried_pubkey_config
= TRUE
;
4484 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4485 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4488 * Try the public key supplied in the configuration.
4490 * First, offer the public blob to see if the server is
4491 * willing to accept it.
4493 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4496 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4497 ssh2_pkt_addstring(username
);
4498 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4499 ssh2_pkt_addstring("publickey"); /* method */
4500 ssh2_pkt_addbool(FALSE
); /* no signature included */
4501 ssh2_pkt_addstring(algorithm
);
4502 ssh2_pkt_addstring_start();
4503 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
4505 logevent("Offered public key"); /* FIXME */
4507 crWaitUntilV(ispkt
);
4508 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4510 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4511 continue; /* key refused; give up on it */
4514 logevent("Offer of public key accepted");
4516 * Actually attempt a serious authentication using
4519 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4521 "Passphrase for key \"%.100s\": ",
4527 c_write_str("Authenticating with public key \"");
4528 c_write_str(comment
);
4529 c_write_str("\"\r\n");
4530 method
= AUTH_PUBLICKEY_FILE
;
4534 if (!method
&& can_keyb_inter
&& !tried_keyb_inter
) {
4535 method
= AUTH_KEYBOARD_INTERACTIVE
;
4536 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4537 tried_keyb_inter
= TRUE
;
4539 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4540 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4542 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4543 ssh2_pkt_addstring(username
);
4544 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4545 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4546 ssh2_pkt_addstring(""); /* lang */
4547 ssh2_pkt_addstring("");
4550 crWaitUntilV(ispkt
);
4551 if (pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4552 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4554 logevent("Keyboard-interactive authentication refused");
4555 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4559 kbd_inter_running
= TRUE
;
4563 if (kbd_inter_running
) {
4564 method
= AUTH_KEYBOARD_INTERACTIVE
;
4565 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4566 tried_keyb_inter
= TRUE
;
4568 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4569 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4571 if (curr_prompt
== 0) {
4573 * We've got a fresh USERAUTH_INFO_REQUEST.
4574 * Display header data, and start going through
4577 char *name
, *inst
, *lang
;
4578 int name_len
, inst_len
, lang_len
;
4580 ssh2_pkt_getstring(&name
, &name_len
);
4581 ssh2_pkt_getstring(&inst
, &inst_len
);
4582 ssh2_pkt_getstring(&lang
, &lang_len
);
4584 c_write_untrusted(name
, name_len
);
4585 c_write_str("\r\n");
4588 c_write_untrusted(inst
, inst_len
);
4589 c_write_str("\r\n");
4591 num_prompts
= ssh2_pkt_getuint32();
4595 * If there are prompts remaining in the packet,
4596 * display one and get a response.
4598 if (curr_prompt
< num_prompts
) {
4602 ssh2_pkt_getstring(&prompt
, &prompt_len
);
4603 if (prompt_len
> 0) {
4604 strncpy(pwprompt
, prompt
, sizeof(pwprompt
));
4605 pwprompt
[prompt_len
< sizeof(pwprompt
) ?
4606 prompt_len
: sizeof(pwprompt
)-1] = '\0';
4609 "<server failed to send prompt>: ");
4611 echo
= ssh2_pkt_getbool();
4617 if (!method
&& can_passwd
) {
4618 method
= AUTH_PASSWORD
;
4619 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4620 ssh_pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4621 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
,
4628 if (!ssh_get_line(pwprompt
, password
,
4629 sizeof(password
), TRUE
)) {
4631 * get_line failed to get a password (for
4632 * example because one was supplied on the
4633 * command line which has already failed to
4636 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4637 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4639 ("No more passwords available to try");
4640 ssh2_pkt_addstring("en"); /* language tag */
4642 logevent("Unable to authenticate");
4643 connection_fatal("Unable to authenticate");
4644 ssh_state
= SSH_STATE_CLOSED
;
4649 c_write_untrusted(pwprompt
, strlen(pwprompt
));
4652 setup_userpass_input(password
, sizeof(password
), echo
);
4654 crWaitUntilV(!ispkt
);
4655 ret
= process_userpass_input(in
, inlen
);
4659 c_write_str("\r\n");
4663 if (method
== AUTH_PUBLICKEY_FILE
) {
4665 * We have our passphrase. Now try the actual authentication.
4667 struct ssh2_userkey
*key
;
4669 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
4670 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4671 if (key
== SSH2_WRONG_PASSPHRASE
) {
4672 c_write_str("Wrong passphrase\r\n");
4673 tried_pubkey_config
= FALSE
;
4675 c_write_str("Unable to load private key\r\n");
4676 tried_pubkey_config
= TRUE
;
4678 /* Send a spurious AUTH_NONE to return to the top. */
4679 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4680 ssh2_pkt_addstring(username
);
4681 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4682 ssh2_pkt_addstring("none"); /* method */
4684 type
= AUTH_TYPE_NONE
;
4686 unsigned char *pkblob
, *sigblob
, *sigdata
;
4687 int pkblob_len
, sigblob_len
, sigdata_len
;
4690 * We have loaded the private key and the server
4691 * has announced that it's willing to accept it.
4692 * Hallelujah. Generate a signature and send it.
4694 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4695 ssh2_pkt_addstring(username
);
4696 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4697 ssh2_pkt_addstring("publickey"); /* method */
4698 ssh2_pkt_addbool(TRUE
);
4699 ssh2_pkt_addstring(key
->alg
->name
);
4700 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4701 ssh2_pkt_addstring_start();
4702 ssh2_pkt_addstring_data(pkblob
, pkblob_len
);
4705 * The data to be signed is:
4709 * followed by everything so far placed in the
4712 sigdata_len
= pktout
.length
- 5 + 4 + 20;
4713 sigdata
= smalloc(sigdata_len
);
4714 PUT_32BIT(sigdata
, 20);
4715 memcpy(sigdata
+ 4, ssh2_session_id
, 20);
4716 memcpy(sigdata
+ 24, pktout
.data
+ 5,
4718 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4719 sigdata_len
, &sigblob_len
);
4720 ssh2_add_sigblob(pkblob
, pkblob_len
,
4721 sigblob
, sigblob_len
);
4727 type
= AUTH_TYPE_PUBLICKEY
;
4729 } else if (method
== AUTH_PASSWORD
) {
4731 * We send the password packet lumped tightly together with
4732 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4733 * string long enough to make the total length of the two
4734 * packets constant. This should ensure that a passive
4735 * listener doing traffic analyis can't work out the length
4738 * For this to work, we need an assumption about the
4739 * maximum length of the password packet. I think 256 is
4740 * pretty conservative. Anyone using a password longer than
4741 * that probably doesn't have much to worry about from
4742 * people who find out how long their password is!
4744 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4745 ssh2_pkt_addstring(username
);
4746 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4747 ssh2_pkt_addstring("password");
4748 ssh2_pkt_addbool(FALSE
);
4749 ssh2_pkt_addstring(password
);
4752 * We'll include a string that's an exact multiple of the
4753 * cipher block size. If the cipher is NULL for some
4754 * reason, we don't do this trick at all because we gain
4760 stringlen
= (256 - deferred_len
);
4761 stringlen
+= cscipher
->blksize
- 1;
4762 stringlen
-= (stringlen
% cscipher
->blksize
);
4765 * Temporarily disable actual compression,
4766 * so we can guarantee to get this string
4767 * exactly the length we want it. The
4768 * compression-disabling routine should
4769 * return an integer indicating how many
4770 * bytes we should adjust our string length
4773 stringlen
-= cscomp
->disable_compression();
4775 ssh2_pkt_init(SSH2_MSG_IGNORE
);
4776 ssh2_pkt_addstring_start();
4777 for (i
= 0; i
< stringlen
; i
++) {
4778 char c
= (char) random_byte();
4779 ssh2_pkt_addstring_data(&c
, 1);
4783 ssh_pkt_defersend();
4784 logevent("Sent password");
4785 type
= AUTH_TYPE_PASSWORD
;
4786 } else if (method
== AUTH_KEYBOARD_INTERACTIVE
) {
4787 if (curr_prompt
== 0) {
4788 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4789 ssh2_pkt_adduint32(num_prompts
);
4791 if (need_pw
) { /* only add pw if we just got one! */
4792 ssh2_pkt_addstring(password
);
4793 memset(password
, 0, sizeof(password
));
4796 if (curr_prompt
>= num_prompts
) {
4800 * If there are prompts remaining, we set
4801 * `gotit' so that we won't attempt to get
4802 * another packet. Then we go back round the
4803 * loop and will end up retrieving another
4804 * prompt out of the existing packet. Funky or
4809 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4812 ("No supported authentication methods left to try!\r\n");
4814 ("No supported authentications offered. Disconnecting");
4815 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4816 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4818 ("No supported authentication methods available");
4819 ssh2_pkt_addstring("en"); /* language tag */
4821 ssh_state
= SSH_STATE_CLOSED
;
4825 } while (!we_are_in
);
4828 * Now we're authenticated for the connection protocol. The
4829 * connection protocol will automatically have started at this
4830 * point; there's no need to send SERVICE_REQUEST.
4834 * So now create a channel with a session in it.
4836 ssh_channels
= newtree234(ssh_channelcmp
);
4837 mainchan
= smalloc(sizeof(struct ssh_channel
));
4838 mainchan
->localid
= alloc_channel_id();
4839 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
4840 ssh2_pkt_addstring("session");
4841 ssh2_pkt_adduint32(mainchan
->localid
);
4842 mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
4843 ssh2_pkt_adduint32(mainchan
->v
.v2
.locwindow
); /* our window size */
4844 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
4846 crWaitUntilV(ispkt
);
4847 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
4848 bombout(("Server refused to open a session"));
4850 /* FIXME: error data comes back in FAILURE packet */
4852 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
4853 bombout(("Server's channel confirmation cited wrong channel"));
4856 mainchan
->remoteid
= ssh2_pkt_getuint32();
4857 mainchan
->type
= CHAN_MAINSESSION
;
4858 mainchan
->closes
= 0;
4859 mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
4860 mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
4861 bufchain_init(&mainchan
->v
.v2
.outbuffer
);
4862 add234(ssh_channels
, mainchan
);
4863 logevent("Opened channel for session");
4866 * Potentially enable X11 forwarding.
4868 if (cfg
.x11_forward
) {
4869 char proto
[20], data
[64];
4870 logevent("Requesting X11 forwarding");
4871 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
4872 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
4873 ssh2_pkt_adduint32(mainchan
->remoteid
);
4874 ssh2_pkt_addstring("x11-req");
4875 ssh2_pkt_addbool(1); /* want reply */
4876 ssh2_pkt_addbool(0); /* many connections */
4877 ssh2_pkt_addstring(proto
);
4878 ssh2_pkt_addstring(data
);
4879 ssh2_pkt_adduint32(0); /* screen number */
4883 crWaitUntilV(ispkt
);
4884 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
4885 unsigned i
= ssh2_pkt_getuint32();
4886 struct ssh_channel
*c
;
4887 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
4889 continue; /* nonexistent channel */
4890 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
4892 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4894 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
4895 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
4896 bombout(("Unexpected response to X11 forwarding request:"
4897 " packet type %d", pktin
.type
));
4900 logevent("X11 forwarding refused");
4902 logevent("X11 forwarding enabled");
4903 ssh_X11_fwd_enabled
= TRUE
;
4908 * Enable port forwardings.
4911 static char *e
; /* preserve across crReturn */
4914 int sport
,dport
,sserv
,dserv
;
4915 char sports
[256], dports
[256], host
[256];
4919 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4920 /* Add port forwardings. */
4925 while (*e
&& *e
!= '\t')
4931 while (*e
&& *e
!= ':')
4941 dport
= atoi(dports
);
4945 se
= getservbyname(dports
, NULL
);
4947 dport
= ntohs(se
->s_port
);
4950 "Service lookup failed for destination port \"%s\"",
4955 sport
= atoi(sports
);
4959 se
= getservbyname(sports
, NULL
);
4961 sport
= ntohs(se
->s_port
);
4964 "Service lookup failed for source port \"%s\"",
4969 if (sport
&& dport
) {
4971 pfd_addforward(host
, dport
, sport
);
4972 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
4973 " %s:%.*s%.*s%d%.*s",
4974 sserv ?
strlen(sports
) : 0, sports
,
4975 sserv
, "(", sport
, sserv
, ")",
4977 dserv ?
strlen(dports
) : 0, dports
,
4978 dserv
, "(", dport
, dserv
, ")");
4981 struct ssh_rportfwd
*pf
;
4982 pf
= smalloc(sizeof(*pf
));
4983 strcpy(pf
->dhost
, host
);
4986 if (add234(ssh_rportfwds
, pf
) != pf
) {
4988 "Duplicate remote port forwarding to %s:%d",
4993 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
4994 " forward to %s:%.*s%.*s%d%.*s",
4995 sserv ?
strlen(sports
) : 0, sports
,
4996 sserv
, "(", sport
, sserv
, ")",
4998 dserv ?
strlen(dports
) : 0, dports
,
4999 dserv
, "(", dport
, dserv
, ")");
5001 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
5002 ssh2_pkt_addstring("tcpip-forward");
5003 ssh2_pkt_addbool(1);/* want reply */
5004 if (cfg
.rport_acceptall
)
5005 ssh2_pkt_addstring("0.0.0.0");
5007 ssh2_pkt_addstring("127.0.0.1");
5008 ssh2_pkt_adduint32(sport
);
5012 crWaitUntilV(ispkt
);
5013 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5014 unsigned i
= ssh2_pkt_getuint32();
5015 struct ssh_channel
*c
;
5016 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5018 continue;/* nonexistent channel */
5019 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5021 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5023 if (pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5024 if (pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5025 bombout(("Unexpected response to port "
5026 "forwarding request: packet type %d",
5030 logevent("Server refused this port forwarding");
5032 logevent("Remote port forwarding enabled");
5041 * Potentially enable agent forwarding.
5043 if (cfg
.agentfwd
&& agent_exists()) {
5044 logevent("Requesting OpenSSH-style agent forwarding");
5045 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5046 ssh2_pkt_adduint32(mainchan
->remoteid
);
5047 ssh2_pkt_addstring("auth-agent-req@openssh.com");
5048 ssh2_pkt_addbool(1); /* want reply */
5052 crWaitUntilV(ispkt
);
5053 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5054 unsigned i
= ssh2_pkt_getuint32();
5055 struct ssh_channel
*c
;
5056 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5058 continue; /* nonexistent channel */
5059 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5061 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5063 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5064 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5065 bombout(("Unexpected response to agent forwarding request:"
5066 " packet type %d", pktin
.type
));
5069 logevent("Agent forwarding refused");
5071 logevent("Agent forwarding enabled");
5072 ssh_agentfwd_enabled
= TRUE
;
5077 * Now allocate a pty for the session.
5080 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5081 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5082 ssh2_pkt_addstring("pty-req");
5083 ssh2_pkt_addbool(1); /* want reply */
5084 ssh2_pkt_addstring(cfg
.termtype
);
5085 ssh2_pkt_adduint32(cols
);
5086 ssh2_pkt_adduint32(rows
);
5087 ssh2_pkt_adduint32(0); /* pixel width */
5088 ssh2_pkt_adduint32(0); /* pixel height */
5089 ssh2_pkt_addstring_start();
5090 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
5092 ssh_state
= SSH_STATE_INTERMED
;
5095 crWaitUntilV(ispkt
);
5096 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5097 unsigned i
= ssh2_pkt_getuint32();
5098 struct ssh_channel
*c
;
5099 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5101 continue; /* nonexistent channel */
5102 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5104 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5106 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5107 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5108 bombout(("Unexpected response to pty request:"
5109 " packet type %d", pktin
.type
));
5112 c_write_str("Server refused to allocate pty\r\n");
5113 ssh_editing
= ssh_echoing
= 1;
5115 logevent("Allocated pty");
5118 ssh_editing
= ssh_echoing
= 1;
5122 * Start a shell or a remote command. We may have to attempt
5123 * this twice if the config data has provided a second choice
5130 if (ssh_fallback_cmd
) {
5131 subsys
= cfg
.ssh_subsys2
;
5132 cmd
= cfg
.remote_cmd_ptr2
;
5134 subsys
= cfg
.ssh_subsys
;
5135 cmd
= cfg
.remote_cmd_ptr
;
5138 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5139 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5141 ssh2_pkt_addstring("subsystem");
5142 ssh2_pkt_addbool(1); /* want reply */
5143 ssh2_pkt_addstring(cmd
);
5145 ssh2_pkt_addstring("exec");
5146 ssh2_pkt_addbool(1); /* want reply */
5147 ssh2_pkt_addstring(cmd
);
5149 ssh2_pkt_addstring("shell");
5150 ssh2_pkt_addbool(1); /* want reply */
5154 crWaitUntilV(ispkt
);
5155 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5156 unsigned i
= ssh2_pkt_getuint32();
5157 struct ssh_channel
*c
;
5158 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5160 continue; /* nonexistent channel */
5161 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5163 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5164 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5165 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5166 bombout(("Unexpected response to shell/command request:"
5167 " packet type %d", pktin
.type
));
5171 * We failed to start the command. If this is the
5172 * fallback command, we really are finished; if it's
5173 * not, and if the fallback command exists, try falling
5174 * back to it before complaining.
5176 if (!ssh_fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5177 logevent("Primary command failed; attempting fallback");
5178 ssh_fallback_cmd
= TRUE
;
5181 bombout(("Server refused to start a shell/command"));
5184 logevent("Started a shell/command");
5189 ssh_state
= SSH_STATE_SESSION
;
5193 ssh_special(TS_EOF
);
5198 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
5201 static int try_send
;
5205 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5206 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5209 unsigned i
= ssh2_pkt_getuint32();
5210 struct ssh_channel
*c
;
5211 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5213 continue; /* nonexistent channel */
5214 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5215 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
5216 continue; /* extended but not stderr */
5217 ssh2_pkt_getstring(&data
, &length
);
5220 c
->v
.v2
.locwindow
-= length
;
5222 case CHAN_MAINSESSION
:
5224 from_backend(pktin
.type
==
5225 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5229 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5232 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5235 while (length
> 0) {
5236 if (c
->u
.a
.lensofar
< 4) {
5237 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5238 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5242 c
->u
.a
.lensofar
+= l
;
5244 if (c
->u
.a
.lensofar
== 4) {
5246 4 + GET_32BIT(c
->u
.a
.msglen
);
5247 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5248 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5250 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5252 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5254 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5258 c
->u
.a
.lensofar
+= l
;
5260 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5261 void *reply
, *sentreply
;
5263 agent_query(c
->u
.a
.message
,
5264 c
->u
.a
.totallen
, &reply
,
5269 /* Fake SSH_AGENT_FAILURE. */
5270 sentreply
= "\0\0\0\1\5";
5273 ssh2_add_channel_data(c
, sentreply
,
5278 sfree(c
->u
.a
.message
);
5279 c
->u
.a
.lensofar
= 0;
5286 * If we are not buffering too much data,
5287 * enlarge the window again at the remote side.
5289 if (bufsize
< OUR_V2_WINSIZE
)
5290 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5292 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
5293 ssh_state
= SSH_STATE_CLOSED
;
5294 logevent("Received disconnect message");
5296 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5297 unsigned i
= ssh2_pkt_getuint32();
5298 struct ssh_channel
*c
;
5300 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5302 continue; /* nonexistent channel */
5304 if (c
->type
== CHAN_X11
) {
5306 * Remote EOF on an X11 channel means we should
5307 * wrap up and close the channel ourselves.
5309 x11_close(c
->u
.x11
.s
);
5311 } else if (c
->type
== CHAN_AGENT
) {
5313 } else if (c
->type
== CHAN_SOCKDATA
) {
5314 pfd_close(c
->u
.pfd
.s
);
5317 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5318 unsigned i
= ssh2_pkt_getuint32();
5319 struct ssh_channel
*c
;
5321 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5323 continue; /* nonexistent channel */
5324 /* Do pre-close processing on the channel. */
5326 case CHAN_MAINSESSION
:
5327 break; /* nothing to see here, move along */
5329 if (c
->u
.x11
.s
!= NULL
)
5330 x11_close(c
->u
.x11
.s
);
5337 if (c
->u
.pfd
.s
!= NULL
)
5338 pfd_close(c
->u
.pfd
.s
);
5342 if (c
->closes
== 0) {
5343 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5344 ssh2_pkt_adduint32(c
->remoteid
);
5347 del234(ssh_channels
, c
);
5348 bufchain_clear(&c
->v
.v2
.outbuffer
);
5352 * See if that was the last channel left open.
5354 if (count234(ssh_channels
) == 0) {
5357 * We used to send SSH_MSG_DISCONNECT here,
5358 * because I'd believed that _every_ conforming
5359 * SSH2 connection had to end with a disconnect
5360 * being sent by at least one side; apparently
5361 * I was wrong and it's perfectly OK to
5362 * unceremoniously slam the connection shut
5363 * when you're done, and indeed OpenSSH feels
5364 * this is more polite than sending a
5365 * DISCONNECT. So now we don't.
5367 logevent("All channels closed. Disconnecting");
5368 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5369 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5370 ssh2_pkt_addstring("All open channels closed");
5371 ssh2_pkt_addstring("en"); /* language tag */
5374 ssh_state
= SSH_STATE_CLOSED
;
5377 continue; /* remote sends close; ignore (FIXME) */
5378 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5379 unsigned i
= ssh2_pkt_getuint32();
5380 struct ssh_channel
*c
;
5381 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5383 continue; /* nonexistent channel */
5384 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5386 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5387 unsigned i
= ssh2_pkt_getuint32();
5388 struct ssh_channel
*c
;
5389 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5391 continue; /* nonexistent channel */
5392 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5393 continue; /* dunno why they're confirming this */
5394 c
->remoteid
= ssh2_pkt_getuint32();
5395 c
->type
= CHAN_SOCKDATA
;
5396 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
5397 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
5399 pfd_confirm(c
->u
.pfd
.s
);
5402 * We have a pending close on this channel,
5403 * which we decided on before the server acked
5404 * the channel open. So now we know the
5405 * remoteid, we can close it again.
5407 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5408 ssh2_pkt_adduint32(c
->remoteid
);
5411 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5412 unsigned i
= ssh2_pkt_getuint32();
5413 struct ssh_channel
*c
;
5414 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5416 continue; /* nonexistent channel */
5417 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5418 continue; /* dunno why they're failing this */
5420 logevent("Forwarded connection refused by server");
5422 pfd_close(c
->u
.pfd
.s
);
5424 del234(ssh_channels
, c
);
5426 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5429 int typelen
, want_reply
;
5430 struct ssh_channel
*c
;
5432 localid
= ssh2_pkt_getuint32();
5433 ssh2_pkt_getstring(&type
, &typelen
);
5434 want_reply
= ssh2_pkt_getbool();
5437 * First, check that the channel exists. Otherwise,
5438 * we can instantly disconnect with a rude message.
5440 c
= find234(ssh_channels
, &localid
, ssh_channelfind
);
5443 sprintf(buf
, "Received channel request for nonexistent"
5444 " channel %d", localid
);
5446 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5447 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5448 ssh2_pkt_addstring(buf
);
5449 ssh2_pkt_addstring("en"); /* language tag */
5451 connection_fatal("%s", buf
);
5452 ssh_state
= SSH_STATE_CLOSED
;
5457 * Having got the channel number, we now look at
5458 * the request type string to see if it's something
5461 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5463 /* We recognise "exit-status" on the primary channel. */
5465 ssh_exitcode
= ssh2_pkt_getuint32();
5466 sprintf(buf
, "Server sent command exit status %d",
5470 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS
);
5471 ssh2_pkt_adduint32(c
->remoteid
);
5476 * This is a channel request we don't know
5477 * about, so we now either ignore the request
5478 * or respond with CHANNEL_FAILURE, depending
5482 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE
);
5483 ssh2_pkt_adduint32(c
->remoteid
);
5487 } else if (pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5489 int typelen
, want_reply
;
5491 ssh2_pkt_getstring(&type
, &typelen
);
5492 want_reply
= ssh2_pkt_getbool();
5495 * We currently don't support any global requests
5496 * at all, so we either ignore the request or
5497 * respond with REQUEST_FAILURE, depending on
5501 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5504 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5508 struct ssh_channel
*c
;
5509 unsigned remid
, winsize
, pktsize
;
5510 ssh2_pkt_getstring(&type
, &typelen
);
5511 c
= smalloc(sizeof(struct ssh_channel
));
5513 remid
= ssh2_pkt_getuint32();
5514 winsize
= ssh2_pkt_getuint32();
5515 pktsize
= ssh2_pkt_getuint32();
5517 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5518 if (!ssh_X11_fwd_enabled
)
5519 error
= "X11 forwarding is not enabled";
5520 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5522 error
= "Unable to open an X11 connection";
5526 } else if (typelen
== 15 &&
5527 !memcmp(type
, "forwarded-tcpip", 15)) {
5528 struct ssh_rportfwd pf
, *realpf
;
5531 ssh2_pkt_getstring(&dummy
, &dummylen
);/* skip address */
5532 pf
.sport
= ssh2_pkt_getuint32();
5533 realpf
= find234(ssh_rportfwds
, &pf
, NULL
);
5534 if (realpf
== NULL
) {
5535 error
= "Remote port is not recognised";
5537 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5540 sprintf(buf
, "Received remote port open request for %s:%d",
5541 realpf
->dhost
, realpf
->dport
);
5544 sprintf(buf
, "Port open failed: %s", e
);
5546 error
= "Port open failed";
5548 logevent("Forwarded port opened successfully");
5549 c
->type
= CHAN_SOCKDATA
;
5552 } else if (typelen
== 22 &&
5553 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5554 if (!ssh_agentfwd_enabled
)
5555 error
= "Agent forwarding is not enabled";
5557 c
->type
= CHAN_AGENT
; /* identify channel type */
5558 c
->u
.a
.lensofar
= 0;
5561 error
= "Unsupported channel type requested";
5564 c
->remoteid
= remid
;
5566 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5567 ssh2_pkt_adduint32(c
->remoteid
);
5568 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
5569 ssh2_pkt_addstring(error
);
5570 ssh2_pkt_addstring("en"); /* language tag */
5574 c
->localid
= alloc_channel_id();
5576 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5577 c
->v
.v2
.remwindow
= winsize
;
5578 c
->v
.v2
.remmaxpkt
= pktsize
;
5579 bufchain_init(&c
->v
.v2
.outbuffer
);
5580 add234(ssh_channels
, c
);
5581 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5582 ssh2_pkt_adduint32(c
->remoteid
);
5583 ssh2_pkt_adduint32(c
->localid
);
5584 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);
5585 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5589 bombout(("Strange packet received: type %d", pktin
.type
));
5594 * We have spare data. Add it to the channel buffer.
5596 ssh2_add_channel_data(mainchan
, in
, inlen
);
5601 struct ssh_channel
*c
;
5603 * Try to send data on all channels if we can.
5605 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
5606 int bufsize
= ssh2_try_send(c
);
5609 case CHAN_MAINSESSION
:
5610 /* stdin need not receive an unthrottle
5611 * notification since it will be polled */
5614 x11_unthrottle(c
->u
.x11
.s
);
5617 /* agent sockets are request/response and need no
5618 * buffer management */
5621 pfd_unthrottle(c
->u
.pfd
.s
);
5633 * Handle the top-level SSH2 protocol.
5635 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
5637 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
5639 do_ssh2_authconn(in
, inlen
, ispkt
);
5643 * Called to set up the connection.
5645 * Returns an error message, or NULL on success.
5647 static char *ssh_init(char *host
, int port
, char **realhost
, int nodelay
)
5652 if (crypto_startup() == 0)
5653 return "Microsoft high encryption pack not installed!";
5659 ssh1_throttle_count
= 0;
5660 ssh_overall_bufsize
= 0;
5661 ssh_fallback_cmd
= 0;
5663 p
= connect_to_host(host
, port
, realhost
, nodelay
);
5671 * Called to send data down the Telnet connection.
5673 static int ssh_send(char *buf
, int len
)
5675 if (s
== NULL
|| ssh_protocol
== NULL
)
5678 ssh_protocol(buf
, len
, 0);
5680 return ssh_sendbuffer();
5684 * Called to query the current amount of buffered stdin data.
5686 static int ssh_sendbuffer(void)
5690 if (s
== NULL
|| ssh_protocol
== NULL
)
5694 * If the SSH socket itself has backed up, add the total backup
5695 * size on that to any individual buffer on the stdin channel.
5698 if (ssh_throttled_all
)
5699 override_value
= ssh_overall_bufsize
;
5701 if (ssh_version
== 1) {
5702 return override_value
;
5703 } else if (ssh_version
== 2) {
5704 if (!mainchan
|| mainchan
->closes
> 0)
5705 return override_value
;
5707 return override_value
+ bufchain_size(&mainchan
->v
.v2
.outbuffer
);
5714 * Called to set the size of the window from SSH's POV.
5716 static void ssh_size(void)
5718 switch (ssh_state
) {
5719 case SSH_STATE_BEFORE_SIZE
:
5720 case SSH_STATE_PREPACKET
:
5721 case SSH_STATE_CLOSED
:
5722 break; /* do nothing */
5723 case SSH_STATE_INTERMED
:
5724 size_needed
= TRUE
; /* buffer for later */
5726 case SSH_STATE_SESSION
:
5728 if (ssh_version
== 1) {
5729 send_packet(SSH1_CMSG_WINDOW_SIZE
,
5730 PKT_INT
, rows
, PKT_INT
, cols
,
5731 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5733 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5734 ssh2_pkt_adduint32(mainchan
->remoteid
);
5735 ssh2_pkt_addstring("window-change");
5736 ssh2_pkt_addbool(0);
5737 ssh2_pkt_adduint32(cols
);
5738 ssh2_pkt_adduint32(rows
);
5739 ssh2_pkt_adduint32(0);
5740 ssh2_pkt_adduint32(0);
5749 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5750 * can send an EOF and collect resulting output (e.g. `plink
5753 static void ssh_special(Telnet_Special code
)
5755 if (code
== TS_EOF
) {
5756 if (ssh_state
!= SSH_STATE_SESSION
) {
5758 * Buffer the EOF in case we are pre-SESSION, so we can
5759 * send it as soon as we reach SESSION.
5765 if (ssh_version
== 1) {
5766 send_packet(SSH1_CMSG_EOF
, PKT_END
);
5768 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
5769 ssh2_pkt_adduint32(mainchan
->remoteid
);
5772 logevent("Sent EOF message");
5773 } else if (code
== TS_PING
) {
5774 if (ssh_state
== SSH_STATE_CLOSED
5775 || ssh_state
== SSH_STATE_PREPACKET
) return;
5776 if (ssh_version
== 1) {
5777 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
5779 ssh2_pkt_init(SSH2_MSG_IGNORE
);
5780 ssh2_pkt_addstring_start();
5788 void *new_sock_channel(Socket s
)
5790 struct ssh_channel
*c
;
5791 c
= smalloc(sizeof(struct ssh_channel
));
5794 c
->remoteid
= -1; /* to be set when open confirmed */
5795 c
->localid
= alloc_channel_id();
5797 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
5799 bufchain_init(&c
->v
.v2
.outbuffer
);
5800 add234(ssh_channels
, c
);
5806 * This is called when stdout/stderr (the entity to which
5807 * from_backend sends data) manages to clear some backlog.
5809 void ssh_unthrottle(int bufsize
)
5811 if (ssh_version
== 1) {
5812 if (ssh1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
5813 ssh1_stdout_throttling
= 0;
5817 if (mainchan
&& mainchan
->closes
== 0)
5818 ssh2_set_window(mainchan
, OUR_V2_WINSIZE
- bufsize
);
5822 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
5824 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
5827 sprintf(buf
, "Opening forwarded connection to %.512s:%d", hostname
, port
);
5830 if (ssh_version
== 1) {
5831 send_packet(SSH1_MSG_PORT_OPEN
,
5832 PKT_INT
, c
->localid
,
5835 //PKT_STR, <org:orgport>,
5838 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
5839 ssh2_pkt_addstring("direct-tcpip");
5840 ssh2_pkt_adduint32(c
->localid
);
5841 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5842 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);/* our window size */
5843 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5844 ssh2_pkt_addstring(hostname
);
5845 ssh2_pkt_adduint32(port
);
5847 * We make up values for the originator data; partly it's
5848 * too much hassle to keep track, and partly I'm not
5849 * convinced the server should be told details like that
5850 * about my local network configuration.
5852 ssh2_pkt_addstring("client-side-connection");
5853 ssh2_pkt_adduint32(0);
5859 static Socket
ssh_socket(void)
5864 static int ssh_sendok(void)
5869 static int ssh_ldisc(int option
)
5871 if (option
== LD_ECHO
)
5873 if (option
== LD_EDIT
)
5878 static int ssh_return_exitcode(void)
5880 return ssh_exitcode
;
5883 Backend ssh_backend
= {
5890 ssh_return_exitcode
,