18 #define logevent(s) { logevent(s); \
19 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
20 { fprintf(stderr, "%s\n", s); fflush(stderr); } }
22 /* logevent, only printf-formatted. */
23 void logeventf(char *fmt
, ...)
29 vsprintf(stuff
, fmt
, ap
);
34 #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \
35 (s ? sk_close(s), s = NULL : 0), \
36 logeventf msg, connection_fatal msg )
38 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
39 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
40 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
41 #define SSH1_CMSG_USER 4 /* 0x4 */
42 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
43 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
44 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
45 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
46 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
47 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
48 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
49 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
50 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
51 #define SSH1_SMSG_FAILURE 15 /* 0xf */
52 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
53 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
54 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
55 #define SSH1_CMSG_EOF 19 /* 0x13 */
56 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
57 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
58 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
59 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
60 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
61 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
62 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
63 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
64 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
65 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
66 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
67 #define SSH1_MSG_IGNORE 32 /* 0x20 */
68 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
69 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
70 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
71 #define SSH1_MSG_DEBUG 36 /* 0x24 */
72 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
73 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
74 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
75 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
76 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
77 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
78 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
80 #define SSH1_AUTH_TIS 5 /* 0x5 */
81 #define SSH1_AUTH_CCARD 16 /* 0x10 */
83 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
84 /* Mask for protoflags we will echo back to server if seen */
85 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
87 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
88 #define SSH2_MSG_IGNORE 2 /* 0x2 */
89 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
90 #define SSH2_MSG_DEBUG 4 /* 0x4 */
91 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
92 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
93 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
94 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
95 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
96 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
97 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
98 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
99 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
100 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
101 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
102 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
103 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
104 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
105 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
106 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
107 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
108 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
109 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
110 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
111 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
112 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
113 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
114 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
115 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
116 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
117 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
118 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
119 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
120 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
121 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
122 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
125 * Packet type contexts, so that ssh2_pkt_type can correctly decode
126 * the ambiguous type numbers back into the correct type strings.
128 #define SSH2_PKTCTX_DHGROUP1 0x0001
129 #define SSH2_PKTCTX_DHGEX 0x0002
130 #define SSH2_PKTCTX_PUBLICKEY 0x0010
131 #define SSH2_PKTCTX_PASSWORD 0x0020
132 #define SSH2_PKTCTX_KBDINTER 0x0040
133 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
135 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
136 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
137 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
138 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
139 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
140 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
141 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
142 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
143 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
144 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
145 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
146 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
147 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
148 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
149 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
151 static const char *const ssh2_disconnect_reasons
[] = {
153 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
154 "SSH_DISCONNECT_PROTOCOL_ERROR",
155 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
156 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
157 "SSH_DISCONNECT_MAC_ERROR",
158 "SSH_DISCONNECT_COMPRESSION_ERROR",
159 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
160 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
161 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
162 "SSH_DISCONNECT_CONNECTION_LOST",
163 "SSH_DISCONNECT_BY_APPLICATION",
164 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
165 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
166 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
167 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
170 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
171 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
172 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
173 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
175 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
178 * Various remote-bug flags.
180 #define BUG_CHOKES_ON_SSH1_IGNORE 1
181 #define BUG_SSH2_HMAC 2
182 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
183 #define BUG_CHOKES_ON_RSA 8
184 #define BUG_SSH2_RSA_PADDING 16
185 #define BUG_SSH2_DERIVEKEY 32
187 static int ssh_pkt_ctx
= 0;
189 #define translate(x) if (type == x) return #x
190 #define translatec(x,ctx) if (type == x && (ssh_pkt_ctx & ctx)) return #x
191 char *ssh1_pkt_type(int type
)
193 translate(SSH1_MSG_DISCONNECT
);
194 translate(SSH1_SMSG_PUBLIC_KEY
);
195 translate(SSH1_CMSG_SESSION_KEY
);
196 translate(SSH1_CMSG_USER
);
197 translate(SSH1_CMSG_AUTH_RSA
);
198 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
199 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
200 translate(SSH1_CMSG_AUTH_PASSWORD
);
201 translate(SSH1_CMSG_REQUEST_PTY
);
202 translate(SSH1_CMSG_WINDOW_SIZE
);
203 translate(SSH1_CMSG_EXEC_SHELL
);
204 translate(SSH1_CMSG_EXEC_CMD
);
205 translate(SSH1_SMSG_SUCCESS
);
206 translate(SSH1_SMSG_FAILURE
);
207 translate(SSH1_CMSG_STDIN_DATA
);
208 translate(SSH1_SMSG_STDOUT_DATA
);
209 translate(SSH1_SMSG_STDERR_DATA
);
210 translate(SSH1_CMSG_EOF
);
211 translate(SSH1_SMSG_EXIT_STATUS
);
212 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
213 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
214 translate(SSH1_MSG_CHANNEL_DATA
);
215 translate(SSH1_MSG_CHANNEL_CLOSE
);
216 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
217 translate(SSH1_SMSG_X11_OPEN
);
218 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
219 translate(SSH1_MSG_PORT_OPEN
);
220 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
221 translate(SSH1_SMSG_AGENT_OPEN
);
222 translate(SSH1_MSG_IGNORE
);
223 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
224 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
225 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
226 translate(SSH1_MSG_DEBUG
);
227 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
228 translate(SSH1_CMSG_AUTH_TIS
);
229 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
230 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
231 translate(SSH1_CMSG_AUTH_CCARD
);
232 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
233 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
236 char *ssh2_pkt_type(int type
)
238 translate(SSH2_MSG_DISCONNECT
);
239 translate(SSH2_MSG_IGNORE
);
240 translate(SSH2_MSG_UNIMPLEMENTED
);
241 translate(SSH2_MSG_DEBUG
);
242 translate(SSH2_MSG_SERVICE_REQUEST
);
243 translate(SSH2_MSG_SERVICE_ACCEPT
);
244 translate(SSH2_MSG_KEXINIT
);
245 translate(SSH2_MSG_NEWKEYS
);
246 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
247 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
248 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
249 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
250 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
251 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
252 translate(SSH2_MSG_USERAUTH_REQUEST
);
253 translate(SSH2_MSG_USERAUTH_FAILURE
);
254 translate(SSH2_MSG_USERAUTH_SUCCESS
);
255 translate(SSH2_MSG_USERAUTH_BANNER
);
256 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
257 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
258 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
259 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
260 translate(SSH2_MSG_GLOBAL_REQUEST
);
261 translate(SSH2_MSG_REQUEST_SUCCESS
);
262 translate(SSH2_MSG_REQUEST_FAILURE
);
263 translate(SSH2_MSG_CHANNEL_OPEN
);
264 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
265 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
266 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
267 translate(SSH2_MSG_CHANNEL_DATA
);
268 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
269 translate(SSH2_MSG_CHANNEL_EOF
);
270 translate(SSH2_MSG_CHANNEL_CLOSE
);
271 translate(SSH2_MSG_CHANNEL_REQUEST
);
272 translate(SSH2_MSG_CHANNEL_SUCCESS
);
273 translate(SSH2_MSG_CHANNEL_FAILURE
);
279 #define GET_32BIT(cp) \
280 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
281 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
282 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
283 ((unsigned long)(unsigned char)(cp)[3]))
285 #define PUT_32BIT(cp, value) { \
286 (cp)[0] = (unsigned char)((value) >> 24); \
287 (cp)[1] = (unsigned char)((value) >> 16); \
288 (cp)[2] = (unsigned char)((value) >> 8); \
289 (cp)[3] = (unsigned char)(value); }
291 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
293 /* Coroutine mechanics for the sillier bits of the code */
294 #define crBegin1 static int crLine = 0;
295 #define crBegin2 switch(crLine) { case 0:;
296 #define crBegin crBegin1; crBegin2;
297 #define crFinish(z) } crLine = 0; return (z)
298 #define crFinishV } crLine = 0; return
299 #define crReturn(z) \
301 crLine=__LINE__; return (z); case __LINE__:;\
305 crLine=__LINE__; return; case __LINE__:;\
307 #define crStop(z) do{ crLine = 0; return (z); }while(0)
308 #define crStopV do{ crLine = 0; return; }while(0)
309 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
310 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
312 extern char *x11_init(Socket
*, char *, void *);
313 extern void x11_close(Socket
);
314 extern int x11_send(Socket
, char *, int);
315 extern void x11_invent_auth(char *, int, char *, int);
316 extern void x11_unthrottle(Socket s
);
317 extern void x11_override_throttle(Socket s
, int enable
);
319 extern char *pfd_newconnect(Socket
* s
, char *hostname
, int port
, void *c
);
320 extern char *pfd_addforward(char *desthost
, int destport
, int port
);
321 extern void pfd_close(Socket s
);
322 extern int pfd_send(Socket s
, char *data
, int len
);
323 extern void pfd_confirm(Socket s
);
324 extern void pfd_unthrottle(Socket s
);
325 extern void pfd_override_throttle(Socket s
, int enable
);
327 static void ssh2_pkt_init(int pkt_type
);
328 static void ssh2_pkt_addbool(unsigned char value
);
329 static void ssh2_pkt_adduint32(unsigned long value
);
330 static void ssh2_pkt_addstring_start(void);
331 static void ssh2_pkt_addstring_str(char *data
);
332 static void ssh2_pkt_addstring_data(char *data
, int len
);
333 static void ssh2_pkt_addstring(char *data
);
334 static char *ssh2_mpint_fmt(Bignum b
, int *len
);
335 static void ssh2_pkt_addmp(Bignum b
);
336 static int ssh2_pkt_construct(void);
337 static void ssh2_pkt_send(void);
340 * Buffer management constants. There are several of these for
341 * various different purposes:
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
360 #define SSH1_BUFFER_LIMIT 32768
361 #define SSH_MAX_BACKLOG 32768
362 #define OUR_V2_WINSIZE 16384
364 const static struct ssh_kex
*kex_algs
[] = {
365 &ssh_diffiehellman_gex
,
369 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
371 static void nullmac_key(unsigned char *key
)
374 static void nullmac_generate(unsigned char *blk
, int len
,
378 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
)
382 const static struct ssh_mac ssh_mac_none
= {
383 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
385 const static struct ssh_mac
*macs
[] = {
386 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
388 const static struct ssh_mac
*buggymacs
[] = {
389 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
392 static void ssh_comp_none_init(void)
395 static int ssh_comp_none_block(unsigned char *block
, int len
,
396 unsigned char **outblock
, int *outlen
)
400 static int ssh_comp_none_disable(void)
404 const static struct ssh_compress ssh_comp_none
= {
406 ssh_comp_none_init
, ssh_comp_none_block
,
407 ssh_comp_none_init
, ssh_comp_none_block
,
408 ssh_comp_none_disable
410 extern const struct ssh_compress ssh_zlib
;
411 const static struct ssh_compress
*compressions
[] = {
412 &ssh_zlib
, &ssh_comp_none
415 enum { /* channel types */
420 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
424 * 2-3-4 tree storing channels.
427 unsigned remoteid
, localid
;
431 struct ssh1_data_channel
{
434 struct ssh2_data_channel
{
436 unsigned remwindow
, remmaxpkt
;
441 struct ssh_agent_channel
{
442 unsigned char *message
;
443 unsigned char msglen
[4];
444 int lensofar
, totallen
;
446 struct ssh_x11_channel
{
449 struct ssh_pfd_channel
{
456 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
457 * 2 use this structure in different ways, reflecting SSH 2's
458 * altogether saner approach to port forwarding.
460 * In SSH 1, you arrange a remote forwarding by sending the server
461 * the remote port number, and the local destination host:port.
462 * When a connection comes in, the server sends you back that
463 * host:port pair, and you connect to it. This is a ready-made
464 * security hole if you're not on the ball: a malicious server
465 * could send you back _any_ host:port pair, so if you trustingly
466 * connect to the address it gives you then you've just opened the
467 * entire inside of your corporate network just by connecting
468 * through it to a dodgy SSH server. Hence, we must store a list of
469 * host:port pairs we _are_ trying to forward to, and reject a
470 * connection request from the server if it's not in the list.
472 * In SSH 2, each side of the connection minds its own business and
473 * doesn't send unnecessary information to the other. You arrange a
474 * remote forwarding by sending the server just the remote port
475 * number. When a connection comes in, the server tells you which
476 * of its ports was connected to; and _you_ have to remember what
477 * local host:port pair went with that port number.
479 * Hence: in SSH 1 this structure stores host:port pairs we intend
480 * to allow connections to, and is indexed by those host:port
481 * pairs. In SSH 2 it stores a mapping from source port to
482 * destination host:port pair, and is indexed by source port.
484 struct ssh_rportfwd
{
485 unsigned sport
, dport
;
498 static SHA_State exhash
, exhashbase
;
500 static Socket s
= NULL
;
502 static unsigned char session_key
[32];
503 static int ssh1_compressing
;
504 static int ssh1_remote_protoflags
;
505 static int ssh1_local_protoflags
;
506 static int ssh_agentfwd_enabled
;
507 static int ssh_X11_fwd_enabled
;
508 static int ssh_remote_bugs
;
509 static const struct ssh_cipher
*cipher
= NULL
;
510 static const struct ssh2_cipher
*cscipher
= NULL
;
511 static const struct ssh2_cipher
*sccipher
= NULL
;
512 static const struct ssh_mac
*csmac
= NULL
;
513 static const struct ssh_mac
*scmac
= NULL
;
514 static const struct ssh_compress
*cscomp
= NULL
;
515 static const struct ssh_compress
*sccomp
= NULL
;
516 static const struct ssh_kex
*kex
= NULL
;
517 static const struct ssh_signkey
*hostkey
= NULL
;
518 static unsigned char ssh2_session_id
[20];
520 static char *savedhost
;
521 static int savedport
;
522 static int ssh_send_ok
;
523 static int ssh_echoing
, ssh_editing
;
525 static tree234
*ssh_channels
; /* indexed by local id */
526 static struct ssh_channel
*mainchan
; /* primary session channel */
527 static int ssh_exitcode
= -1;
529 static tree234
*ssh_rportfwds
;
533 SSH_STATE_BEFORE_SIZE
,
537 } ssh_state
= SSH_STATE_PREPACKET
;
539 static int size_needed
= FALSE
, eof_needed
= FALSE
;
541 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
542 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
543 static unsigned char *deferred_send_data
= NULL
;
544 static int deferred_len
= 0, deferred_size
= 0;
547 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
548 * that fails. This variable is the means by which scp.c can reach
549 * into the SSH code and find out which one it got.
551 int ssh_fallback_cmd
= 0;
553 static int ssh_version
;
554 static int ssh1_throttle_count
;
555 static int ssh_overall_bufsize
;
556 static int ssh_throttled_all
;
557 static int ssh1_stdout_throttling
;
558 static void (*ssh_protocol
) (unsigned char *in
, int inlen
, int ispkt
);
559 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
560 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
561 static void ssh_size(void);
562 static void ssh_special(Telnet_Special
);
563 static int ssh2_try_send(struct ssh_channel
*c
);
564 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
566 static void ssh_throttle_all(int enable
, int bufsize
);
567 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
568 static int (*s_rdpkt
) (unsigned char **data
, int *datalen
);
569 static int ssh_sendbuffer(void);
571 static struct rdpkt1_state_tag
{
572 long len
, pad
, biglen
, to_read
;
573 unsigned long realcrc
, gotcrc
;
579 static struct rdpkt2_state_tag
{
580 long len
, pad
, payload
, packetlen
, maclen
;
583 unsigned long incoming_sequence
;
586 static int ssh_channelcmp(void *av
, void *bv
)
588 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
589 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
590 if (a
->localid
< b
->localid
)
592 if (a
->localid
> b
->localid
)
596 static int ssh_channelfind(void *av
, void *bv
)
598 unsigned *a
= (unsigned *) av
;
599 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
607 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
609 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
610 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
612 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
613 return i
< 0 ?
-1 : +1;
614 if (a
->dport
> b
->dport
)
616 if (a
->dport
< b
->dport
)
621 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
623 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
624 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
626 if (a
->sport
> b
->sport
)
628 if (a
->sport
< b
->sport
)
633 static int alloc_channel_id(void)
635 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
636 unsigned low
, high
, mid
;
638 struct ssh_channel
*c
;
641 * First-fit allocation of channel numbers: always pick the
642 * lowest unused one. To do this, binary-search using the
643 * counted B-tree to find the largest channel ID which is in a
644 * contiguous sequence from the beginning. (Precisely
645 * everything in that sequence must have ID equal to its tree
646 * index plus CHANNEL_NUMBER_OFFSET.)
648 tsize
= count234(ssh_channels
);
652 while (high
- low
> 1) {
653 mid
= (high
+ low
) / 2;
654 c
= index234(ssh_channels
, mid
);
655 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
656 low
= mid
; /* this one is fine */
658 high
= mid
; /* this one is past it */
661 * Now low points to either -1, or the tree index of the
662 * largest ID in the initial sequence.
665 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
666 assert(NULL
== find234(ssh_channels
, &i
, ssh_channelfind
));
668 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
671 static void c_write(char *buf
, int len
)
673 if ((flags
& FLAG_STDERR
)) {
675 for (i
= 0; i
< len
; i
++)
677 fputc(buf
[i
], stderr
);
680 from_backend(1, buf
, len
);
683 static void c_write_untrusted(char *buf
, int len
)
686 for (i
= 0; i
< len
; i
++) {
689 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
694 static void c_write_str(char *buf
)
696 c_write(buf
, strlen(buf
));
700 * Collect incoming data in the incoming packet buffer.
701 * Decipher and verify the packet when it is completely read.
702 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
703 * Update the *data and *datalen variables.
704 * Return the additional nr of bytes needed, or 0 when
705 * a complete packet is available.
707 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
709 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
718 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
719 while ((*datalen
) == 0)
721 st
->len
= (st
->len
<< 8) + **data
;
722 (*data
)++, (*datalen
)--;
725 st
->pad
= 8 - (st
->len
% 8);
726 st
->biglen
= st
->len
+ st
->pad
;
727 pktin
.length
= st
->len
- 5;
729 if (pktin
.maxlen
< st
->biglen
) {
730 pktin
.maxlen
= st
->biglen
;
731 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+ APIEXTRA
) :
732 srealloc(pktin
.data
, st
->biglen
+ APIEXTRA
));
734 fatalbox("Out of memory");
737 st
->to_read
= st
->biglen
;
739 while (st
->to_read
> 0) {
740 st
->chunk
= st
->to_read
;
741 while ((*datalen
) == 0)
742 crReturn(st
->to_read
);
743 if (st
->chunk
> (*datalen
))
744 st
->chunk
= (*datalen
);
745 memcpy(st
->p
, *data
, st
->chunk
);
747 *datalen
-= st
->chunk
;
749 st
->to_read
-= st
->chunk
;
752 if (cipher
&& detect_attack(pktin
.data
, st
->biglen
, NULL
)) {
753 bombout(("Network attack (CRC compensation) detected!"));
758 cipher
->decrypt(pktin
.data
, st
->biglen
);
760 st
->realcrc
= crc32(pktin
.data
, st
->biglen
- 4);
761 st
->gotcrc
= GET_32BIT(pktin
.data
+ st
->biglen
- 4);
762 if (st
->gotcrc
!= st
->realcrc
) {
763 bombout(("Incorrect CRC received on packet"));
767 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
769 if (ssh1_compressing
) {
770 unsigned char *decompblk
;
772 zlib_decompress_block(pktin
.body
- 1, pktin
.length
+ 1,
773 &decompblk
, &decomplen
);
775 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
776 pktin
.maxlen
= st
->pad
+ decomplen
;
777 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+ APIEXTRA
);
778 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
780 fatalbox("Out of memory");
783 memcpy(pktin
.body
- 1, decompblk
, decomplen
);
785 pktin
.length
= decomplen
- 1;
788 pktin
.type
= pktin
.body
[-1];
790 log_packet(PKT_INCOMING
, pktin
.type
, ssh1_pkt_type(pktin
.type
),
791 pktin
.body
, pktin
.length
);
793 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
794 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
795 pktin
.type
== SSH1_MSG_DEBUG
||
796 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
797 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
798 long stringlen
= GET_32BIT(pktin
.body
);
799 if (stringlen
+ 4 != pktin
.length
) {
800 bombout(("Received data packet with bogus string length"));
805 if (pktin
.type
== SSH1_MSG_DEBUG
) {
806 /* log debug message */
808 int stringlen
= GET_32BIT(pktin
.body
);
809 strcpy(buf
, "Remote debug message: ");
812 memcpy(buf
+ 8, pktin
.body
+ 4, stringlen
);
813 buf
[8 + stringlen
] = '\0';
816 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
821 if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
822 /* log reason code in disconnect message */
824 unsigned msglen
= GET_32BIT(pktin
.body
);
826 strcpy(buf
, "Remote sent disconnect: ");
827 nowlen
= strlen(buf
);
828 if (msglen
> sizeof(buf
) - nowlen
- 1)
829 msglen
= sizeof(buf
) - nowlen
- 1;
830 memcpy(buf
+ nowlen
, pktin
.body
+ 4, msglen
);
831 buf
[nowlen
+ msglen
] = '\0';
832 /* logevent(buf); (this is now done within the bombout macro) */
833 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
840 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
842 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
850 st
->cipherblk
= sccipher
->blksize
;
853 if (st
->cipherblk
< 8)
856 if (pktin
.maxlen
< st
->cipherblk
) {
857 pktin
.maxlen
= st
->cipherblk
;
860 NULL ?
smalloc(st
->cipherblk
+
861 APIEXTRA
) : srealloc(pktin
.data
,
865 fatalbox("Out of memory");
869 * Acquire and decrypt the first block of the packet. This will
870 * contain the length and padding details.
872 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
873 while ((*datalen
) == 0)
874 crReturn(st
->cipherblk
- st
->i
);
875 pktin
.data
[st
->i
] = *(*data
)++;
880 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
883 * Now get the length and padding figures.
885 st
->len
= GET_32BIT(pktin
.data
);
886 st
->pad
= pktin
.data
[4];
889 * _Completely_ silly lengths should be stomped on before they
890 * do us any more damage.
892 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
893 bombout(("Incoming packet was garbled on decryption"));
898 * This enables us to deduce the payload length.
900 st
->payload
= st
->len
- st
->pad
- 1;
902 pktin
.length
= st
->payload
+ 5;
905 * So now we can work out the total packet length.
907 st
->packetlen
= st
->len
+ 4;
908 st
->maclen
= scmac ? scmac
->len
: 0;
911 * Adjust memory allocation if packet is too big.
913 if (pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
914 pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
917 NULL ?
smalloc(pktin
.maxlen
+ APIEXTRA
) : srealloc(pktin
.data
,
922 fatalbox("Out of memory");
926 * Read and decrypt the remainder of the packet.
928 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
930 while ((*datalen
) == 0)
931 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
932 pktin
.data
[st
->i
] = *(*data
)++;
935 /* Decrypt everything _except_ the MAC. */
937 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
938 st
->packetlen
- st
->cipherblk
);
944 && !scmac
->verify(pktin
.data
, st
->len
+ 4,
945 st
->incoming_sequence
)) {
946 bombout(("Incorrect MAC received on packet"));
949 st
->incoming_sequence
++; /* whether or not we MACed */
952 * Decompress packet payload.
955 unsigned char *newpayload
;
957 if (sccomp
&& sccomp
->decompress(pktin
.data
+ 5, pktin
.length
- 5,
958 &newpayload
, &newlen
)) {
959 if (pktin
.maxlen
< newlen
+ 5) {
960 pktin
.maxlen
= newlen
+ 5;
963 NULL ?
smalloc(pktin
.maxlen
+
964 APIEXTRA
) : srealloc(pktin
.data
,
968 fatalbox("Out of memory");
970 pktin
.length
= 5 + newlen
;
971 memcpy(pktin
.data
+ 5, newpayload
, newlen
);
977 pktin
.type
= pktin
.data
[5];
979 log_packet(PKT_INCOMING
, pktin
.type
, ssh2_pkt_type(pktin
.type
),
980 pktin
.data
+6, pktin
.length
-6);
982 switch (pktin
.type
) {
984 * These packets we must handle instantly.
986 case SSH2_MSG_DISCONNECT
:
988 /* log reason code in disconnect message */
990 int reason
= GET_32BIT(pktin
.data
+ 6);
991 unsigned msglen
= GET_32BIT(pktin
.data
+ 10);
993 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
994 sprintf(buf
, "Received disconnect message (%s)",
995 ssh2_disconnect_reasons
[reason
]);
997 sprintf(buf
, "Received disconnect message (unknown type %d)",
1001 strcpy(buf
, "Disconnection message text: ");
1002 nowlen
= strlen(buf
);
1003 if (msglen
> sizeof(buf
) - nowlen
- 1)
1004 msglen
= sizeof(buf
) - nowlen
- 1;
1005 memcpy(buf
+ nowlen
, pktin
.data
+ 14, msglen
);
1006 buf
[nowlen
+ msglen
] = '\0';
1008 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1010 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1011 ssh2_disconnect_reasons
[reason
] : "unknown",
1016 case SSH2_MSG_IGNORE
:
1018 case SSH2_MSG_DEBUG
:
1020 /* log the debug message */
1022 /* int display = pktin.body[6]; */
1023 int stringlen
= GET_32BIT(pktin
.data
+7);
1025 strcpy(buf
, "Remote debug message: ");
1026 prefix
= strlen(buf
);
1027 if (stringlen
> sizeof(buf
)-prefix
-1)
1028 stringlen
= sizeof(buf
)-prefix
-1;
1029 memcpy(buf
+ prefix
, pktin
.data
+ 11, stringlen
);
1030 buf
[prefix
+ stringlen
] = '\0';
1033 goto next_packet
; /* FIXME: print the debug message */
1036 * These packets we need do nothing about here.
1038 case SSH2_MSG_UNIMPLEMENTED
:
1039 case SSH2_MSG_SERVICE_REQUEST
:
1040 case SSH2_MSG_SERVICE_ACCEPT
:
1041 case SSH2_MSG_KEXINIT
:
1042 case SSH2_MSG_NEWKEYS
:
1043 case SSH2_MSG_KEXDH_INIT
:
1044 case SSH2_MSG_KEXDH_REPLY
:
1045 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1046 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1047 case SSH2_MSG_KEX_DH_GEX_INIT
:
1048 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1049 case SSH2_MSG_USERAUTH_REQUEST
:
1050 case SSH2_MSG_USERAUTH_FAILURE
:
1051 case SSH2_MSG_USERAUTH_SUCCESS
:
1052 case SSH2_MSG_USERAUTH_BANNER
:
1053 case SSH2_MSG_USERAUTH_PK_OK
:
1054 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1055 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1056 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1057 case SSH2_MSG_GLOBAL_REQUEST
:
1058 case SSH2_MSG_REQUEST_SUCCESS
:
1059 case SSH2_MSG_REQUEST_FAILURE
:
1060 case SSH2_MSG_CHANNEL_OPEN
:
1061 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1062 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1063 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1064 case SSH2_MSG_CHANNEL_DATA
:
1065 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1066 case SSH2_MSG_CHANNEL_EOF
:
1067 case SSH2_MSG_CHANNEL_CLOSE
:
1068 case SSH2_MSG_CHANNEL_REQUEST
:
1069 case SSH2_MSG_CHANNEL_SUCCESS
:
1070 case SSH2_MSG_CHANNEL_FAILURE
:
1074 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1077 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
1078 ssh2_pkt_adduint32(st
->incoming_sequence
- 1);
1086 static void ssh1_pktout_size(int len
)
1090 len
+= 5; /* type and CRC */
1091 pad
= 8 - (len
% 8);
1094 pktout
.length
= len
- 5;
1095 if (pktout
.maxlen
< biglen
) {
1096 pktout
.maxlen
= biglen
;
1098 /* Allocate enough buffer space for extra block
1099 * for MS CryptEncrypt() */
1100 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 12) :
1101 srealloc(pktout
.data
, biglen
+ 12));
1103 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 4) :
1104 srealloc(pktout
.data
, biglen
+ 4));
1107 fatalbox("Out of memory");
1109 pktout
.body
= pktout
.data
+ 4 + pad
+ 1;
1112 static void s_wrpkt_start(int type
, int len
)
1114 ssh1_pktout_size(len
);
1118 static int s_wrpkt_prepare(void)
1120 int pad
, len
, biglen
, i
;
1123 pktout
.body
[-1] = pktout
.type
;
1125 log_packet(PKT_OUTGOING
, pktout
.type
, ssh1_pkt_type(pktout
.type
),
1126 pktout
.body
, pktout
.length
);
1128 if (ssh1_compressing
) {
1129 unsigned char *compblk
;
1131 zlib_compress_block(pktout
.body
- 1, pktout
.length
+ 1,
1132 &compblk
, &complen
);
1133 ssh1_pktout_size(complen
- 1);
1134 memcpy(pktout
.body
- 1, compblk
, complen
);
1138 len
= pktout
.length
+ 5; /* type and CRC */
1139 pad
= 8 - (len
% 8);
1142 for (i
= 0; i
< pad
; i
++)
1143 pktout
.data
[i
+ 4] = random_byte();
1144 crc
= crc32(pktout
.data
+ 4, biglen
- 4);
1145 PUT_32BIT(pktout
.data
+ biglen
, crc
);
1146 PUT_32BIT(pktout
.data
, len
);
1149 cipher
->encrypt(pktout
.data
+ 4, biglen
);
1154 static void s_wrpkt(void)
1157 len
= s_wrpkt_prepare();
1158 backlog
= sk_write(s
, pktout
.data
, len
);
1159 if (backlog
> SSH_MAX_BACKLOG
)
1160 ssh_throttle_all(1, backlog
);
1163 static void s_wrpkt_defer(void)
1166 len
= s_wrpkt_prepare();
1167 if (deferred_len
+ len
> deferred_size
) {
1168 deferred_size
= deferred_len
+ len
+ 128;
1169 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1171 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1172 deferred_len
+= len
;
1176 * Construct a packet with the specified contents.
1178 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
1180 unsigned char *p
, *argp
, argchar
;
1181 unsigned long argint
;
1182 int pktlen
, argtype
, arglen
;
1186 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1189 (void) va_arg(ap1
, int);
1193 (void) va_arg(ap1
, char);
1197 (void) va_arg(ap1
, unsigned char *);
1198 arglen
= va_arg(ap1
, int);
1202 argp
= va_arg(ap1
, unsigned char *);
1203 arglen
= strlen(argp
);
1204 pktlen
+= 4 + arglen
;
1207 bn
= va_arg(ap1
, Bignum
);
1208 pktlen
+= ssh1_bignum_length(bn
);
1215 s_wrpkt_start(pkttype
, pktlen
);
1218 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1221 argint
= va_arg(ap2
, int);
1222 PUT_32BIT(p
, argint
);
1226 argchar
= va_arg(ap2
, unsigned char);
1231 argp
= va_arg(ap2
, unsigned char *);
1232 arglen
= va_arg(ap2
, int);
1233 memcpy(p
, argp
, arglen
);
1237 argp
= va_arg(ap2
, unsigned char *);
1238 arglen
= strlen(argp
);
1239 PUT_32BIT(p
, arglen
);
1240 memcpy(p
+ 4, argp
, arglen
);
1244 bn
= va_arg(ap2
, Bignum
);
1245 p
+= ssh1_write_bignum(p
, bn
);
1251 static void send_packet(int pkttype
, ...)
1254 va_start(ap1
, pkttype
);
1255 va_start(ap2
, pkttype
);
1256 construct_packet(pkttype
, ap1
, ap2
);
1260 static void defer_packet(int pkttype
, ...)
1263 va_start(ap1
, pkttype
);
1264 va_start(ap2
, pkttype
);
1265 construct_packet(pkttype
, ap1
, ap2
);
1269 static int ssh_versioncmp(char *a
, char *b
)
1272 unsigned long av
, bv
;
1274 av
= strtoul(a
, &ae
, 10);
1275 bv
= strtoul(b
, &be
, 10);
1277 return (av
< bv ?
-1 : +1);
1282 av
= strtoul(ae
, &ae
, 10);
1283 bv
= strtoul(be
, &be
, 10);
1285 return (av
< bv ?
-1 : +1);
1291 * Utility routines for putting an SSH-protocol `string' and
1292 * `uint32' into a SHA state.
1295 static void sha_string(SHA_State
* s
, void *str
, int len
)
1297 unsigned char lenblk
[4];
1298 PUT_32BIT(lenblk
, len
);
1299 SHA_Bytes(s
, lenblk
, 4);
1300 SHA_Bytes(s
, str
, len
);
1303 static void sha_uint32(SHA_State
* s
, unsigned i
)
1305 unsigned char intblk
[4];
1306 PUT_32BIT(intblk
, i
);
1307 SHA_Bytes(s
, intblk
, 4);
1311 * SSH2 packet construction functions.
1313 static void ssh2_pkt_ensure(int length
)
1315 if (pktout
.maxlen
< length
) {
1316 pktout
.maxlen
= length
+ 256;
1319 NULL ?
smalloc(pktout
.maxlen
+
1320 APIEXTRA
) : srealloc(pktout
.data
,
1324 fatalbox("Out of memory");
1327 static void ssh2_pkt_adddata(void *data
, int len
)
1329 pktout
.length
+= len
;
1330 ssh2_pkt_ensure(pktout
.length
);
1331 memcpy(pktout
.data
+ pktout
.length
- len
, data
, len
);
1333 static void ssh2_pkt_addbyte(unsigned char byte
)
1335 ssh2_pkt_adddata(&byte
, 1);
1337 static void ssh2_pkt_init(int pkt_type
)
1340 ssh2_pkt_addbyte((unsigned char) pkt_type
);
1342 static void ssh2_pkt_addbool(unsigned char value
)
1344 ssh2_pkt_adddata(&value
, 1);
1346 static void ssh2_pkt_adduint32(unsigned long value
)
1349 PUT_32BIT(x
, value
);
1350 ssh2_pkt_adddata(x
, 4);
1352 static void ssh2_pkt_addstring_start(void)
1354 ssh2_pkt_adduint32(0);
1355 pktout
.savedpos
= pktout
.length
;
1357 static void ssh2_pkt_addstring_str(char *data
)
1359 ssh2_pkt_adddata(data
, strlen(data
));
1360 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1361 pktout
.length
- pktout
.savedpos
);
1363 static void ssh2_pkt_addstring_data(char *data
, int len
)
1365 ssh2_pkt_adddata(data
, len
);
1366 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1367 pktout
.length
- pktout
.savedpos
);
1369 static void ssh2_pkt_addstring(char *data
)
1371 ssh2_pkt_addstring_start();
1372 ssh2_pkt_addstring_str(data
);
1374 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1377 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1380 fatalbox("out of memory");
1382 for (i
= 1; i
<= n
; i
++)
1383 p
[i
] = bignum_byte(b
, n
- i
);
1385 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1387 memmove(p
, p
+ i
, n
+ 1 - i
);
1391 static void ssh2_pkt_addmp(Bignum b
)
1395 p
= ssh2_mpint_fmt(b
, &len
);
1396 ssh2_pkt_addstring_start();
1397 ssh2_pkt_addstring_data(p
, len
);
1402 * Construct an SSH2 final-form packet: compress it, encrypt it,
1403 * put the MAC on it. Final packet, ready to be sent, is stored in
1404 * pktout.data. Total length is returned.
1406 static int ssh2_pkt_construct(void)
1408 int cipherblk
, maclen
, padding
, i
;
1409 static unsigned long outgoing_sequence
= 0;
1411 log_packet(PKT_OUTGOING
, pktout
.data
[5], ssh2_pkt_type(pktout
.data
[5]),
1412 pktout
.data
+ 6, pktout
.length
- 6);
1415 * Compress packet payload.
1418 unsigned char *newpayload
;
1420 if (cscomp
&& cscomp
->compress(pktout
.data
+ 5, pktout
.length
- 5,
1421 &newpayload
, &newlen
)) {
1423 ssh2_pkt_adddata(newpayload
, newlen
);
1429 * Add padding. At least four bytes, and must also bring total
1430 * length (minus MAC) up to a multiple of the block size.
1432 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
1433 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1436 (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1437 maclen
= csmac ? csmac
->len
: 0;
1438 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
1439 pktout
.data
[4] = padding
;
1440 for (i
= 0; i
< padding
; i
++)
1441 pktout
.data
[pktout
.length
+ i
] = random_byte();
1442 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
1444 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
1446 outgoing_sequence
++; /* whether or not we MACed */
1449 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
1451 /* Ready-to-send packet starts at pktout.data. We return length. */
1452 return pktout
.length
+ padding
+ maclen
;
1456 * Construct and send an SSH2 packet immediately.
1458 static void ssh2_pkt_send(void)
1462 len
= ssh2_pkt_construct();
1463 backlog
= sk_write(s
, pktout
.data
, len
);
1464 if (backlog
> SSH_MAX_BACKLOG
)
1465 ssh_throttle_all(1, backlog
);
1469 * Construct an SSH2 packet and add it to a deferred data block.
1470 * Useful for sending multiple packets in a single sk_write() call,
1471 * to prevent a traffic-analysing listener from being able to work
1472 * out the length of any particular packet (such as the password
1475 * Note that because SSH2 sequence-numbers its packets, this can
1476 * NOT be used as an m4-style `defer' allowing packets to be
1477 * constructed in one order and sent in another.
1479 static void ssh2_pkt_defer(void)
1481 int len
= ssh2_pkt_construct();
1482 if (deferred_len
+ len
> deferred_size
) {
1483 deferred_size
= deferred_len
+ len
+ 128;
1484 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1486 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1487 deferred_len
+= len
;
1491 * Send the whole deferred data block constructed by
1492 * ssh2_pkt_defer() or SSH1's defer_packet().
1494 static void ssh_pkt_defersend(void)
1497 backlog
= sk_write(s
, deferred_send_data
, deferred_len
);
1498 deferred_len
= deferred_size
= 0;
1499 sfree(deferred_send_data
);
1500 deferred_send_data
= NULL
;
1501 if (backlog
> SSH_MAX_BACKLOG
)
1502 ssh_throttle_all(1, backlog
);
1506 void bndebug(char *string
, Bignum b
)
1510 p
= ssh2_mpint_fmt(b
, &len
);
1511 debug(("%s", string
));
1512 for (i
= 0; i
< len
; i
++)
1513 debug((" %02x", p
[i
]));
1519 static void sha_mpint(SHA_State
* s
, Bignum b
)
1523 p
= ssh2_mpint_fmt(b
, &len
);
1524 sha_string(s
, p
, len
);
1529 * SSH2 packet decode functions.
1531 static unsigned long ssh2_pkt_getuint32(void)
1533 unsigned long value
;
1534 if (pktin
.length
- pktin
.savedpos
< 4)
1535 return 0; /* arrgh, no way to decline (FIXME?) */
1536 value
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1537 pktin
.savedpos
+= 4;
1540 static int ssh2_pkt_getbool(void)
1542 unsigned long value
;
1543 if (pktin
.length
- pktin
.savedpos
< 1)
1544 return 0; /* arrgh, no way to decline (FIXME?) */
1545 value
= pktin
.data
[pktin
.savedpos
] != 0;
1549 static void ssh2_pkt_getstring(char **p
, int *length
)
1553 if (pktin
.length
- pktin
.savedpos
< 4)
1555 *length
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1556 pktin
.savedpos
+= 4;
1557 if (pktin
.length
- pktin
.savedpos
< *length
)
1559 *p
= pktin
.data
+ pktin
.savedpos
;
1560 pktin
.savedpos
+= *length
;
1562 static Bignum
ssh2_pkt_getmp(void)
1568 ssh2_pkt_getstring(&p
, &length
);
1572 bombout(("internal error: Can't handle negative mpints"));
1575 b
= bignum_from_bytes(p
, length
);
1580 * Helper function to add an SSH2 signature blob to a packet.
1581 * Expects to be shown the public key blob as well as the signature
1582 * blob. Normally works just like ssh2_pkt_addstring, but will
1583 * fiddle with the signature packet if necessary for
1584 * BUG_SSH2_RSA_PADDING.
1586 static void ssh2_add_sigblob(void *pkblob_v
, int pkblob_len
,
1587 void *sigblob_v
, int sigblob_len
)
1589 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1590 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1592 /* dmemdump(pkblob, pkblob_len); */
1593 /* dmemdump(sigblob, sigblob_len); */
1596 * See if this is in fact an ssh-rsa signature and a buggy
1597 * server; otherwise we can just do this the easy way.
1599 if ((ssh_remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1600 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1601 int pos
, len
, siglen
;
1604 * Find the byte length of the modulus.
1607 pos
= 4+7; /* skip over "ssh-rsa" */
1608 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1609 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1610 pos
+= 4; /* find modulus itself */
1611 while (len
> 0 && pkblob
[pos
] == 0)
1613 /* debug(("modulus length is %d\n", len)); */
1616 * Now find the signature integer.
1618 pos
= 4+7; /* skip over "ssh-rsa" */
1619 siglen
= GET_32BIT(sigblob
+pos
);
1620 /* debug(("signature length is %d\n", siglen)); */
1622 if (len
!= siglen
) {
1623 unsigned char newlen
[4];
1624 ssh2_pkt_addstring_start();
1625 ssh2_pkt_addstring_data(sigblob
, pos
);
1626 /* dmemdump(sigblob, pos); */
1627 pos
+= 4; /* point to start of actual sig */
1628 PUT_32BIT(newlen
, len
);
1629 ssh2_pkt_addstring_data(newlen
, 4);
1630 /* dmemdump(newlen, 4); */
1632 while (len
-- > siglen
) {
1633 ssh2_pkt_addstring_data(newlen
, 1);
1634 /* dmemdump(newlen, 1); */
1636 ssh2_pkt_addstring_data(sigblob
+pos
, siglen
);
1637 /* dmemdump(sigblob+pos, siglen); */
1641 /* Otherwise fall through and do it the easy way. */
1644 ssh2_pkt_addstring_start();
1645 ssh2_pkt_addstring_data(sigblob
, sigblob_len
);
1649 * Examine the remote side's version string and compare it against
1650 * a list of known buggy implementations.
1652 static void ssh_detect_bugs(char *vstring
)
1654 char *imp
; /* pointer to implementation part */
1656 imp
+= strcspn(imp
, "-");
1658 imp
+= strcspn(imp
, "-");
1661 ssh_remote_bugs
= 0;
1663 if (cfg
.sshbug_ignore1
== BUG_ON
||
1664 (cfg
.sshbug_ignore1
== BUG_AUTO
&&
1665 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1666 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1667 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")))) {
1669 * These versions don't support SSH1_MSG_IGNORE, so we have
1670 * to use a different defence against password length
1673 ssh_remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1674 logevent("We believe remote version has SSH1 ignore bug");
1677 if (cfg
.sshbug_plainpw1
== BUG_ON
||
1678 (cfg
.sshbug_plainpw1
== BUG_AUTO
&&
1679 (!strcmp(imp
, "Cisco-1.25")))) {
1681 * These versions need a plain password sent; they can't
1682 * handle having a null and a random length of data after
1685 ssh_remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1686 logevent("We believe remote version needs a plain SSH1 password");
1689 if (cfg
.sshbug_rsa1
== BUG_ON
||
1690 (cfg
.sshbug_rsa1
== BUG_AUTO
&&
1691 (!strcmp(imp
, "Cisco-1.25")))) {
1693 * These versions apparently have no clue whatever about
1694 * RSA authentication and will panic and die if they see
1695 * an AUTH_RSA message.
1697 ssh_remote_bugs
|= BUG_CHOKES_ON_RSA
;
1698 logevent("We believe remote version can't handle RSA authentication");
1701 if (cfg
.sshbug_hmac2
== BUG_ON
||
1702 (cfg
.sshbug_hmac2
== BUG_AUTO
&&
1703 (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1704 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1705 !strncmp(imp
, "2.1 ", 4)))) {
1707 * These versions have the HMAC bug.
1709 ssh_remote_bugs
|= BUG_SSH2_HMAC
;
1710 logevent("We believe remote version has SSH2 HMAC bug");
1713 if (cfg
.sshbug_derivekey2
== BUG_ON
||
1714 (cfg
.sshbug_derivekey2
== BUG_AUTO
&&
1715 (!strncmp(imp
, "2.0.", 4)))) {
1717 * These versions have the key-derivation bug (failing to
1718 * include the literal shared secret in the hashes that
1719 * generate the keys).
1721 ssh_remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1722 logevent("We believe remote version has SSH2 key-derivation bug");
1725 if (cfg
.sshbug_rsapad2
== BUG_ON
||
1726 (cfg
.sshbug_rsapad2
== BUG_AUTO
&&
1727 ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1728 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')))){
1730 * These versions have the SSH2 RSA padding bug.
1732 ssh_remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1733 logevent("We believe remote version has SSH2 RSA padding bug");
1737 static int do_ssh_init(unsigned char c
)
1740 static char version
[10];
1741 static char *vstring
;
1742 static int vstrsize
;
1745 static int proto1
, proto2
;
1749 /* Search for the string "SSH-" in the input. */
1752 static const int transS
[] = { 1, 2, 2, 1 };
1753 static const int transH
[] = { 0, 0, 3, 0 };
1754 static const int transminus
[] = { 0, 0, 0, -1 };
1765 crReturn(1); /* get another character */
1769 vstring
= smalloc(vstrsize
);
1770 strcpy(vstring
, "SSH-");
1774 crReturn(1); /* get another char */
1775 if (vslen
>= vstrsize
- 1) {
1777 vstring
= srealloc(vstring
, vstrsize
);
1779 vstring
[vslen
++] = c
;
1784 } else if (i
< sizeof(version
) - 1)
1786 } else if (c
== '\n')
1790 ssh_agentfwd_enabled
= FALSE
;
1791 rdpkt2_state
.incoming_sequence
= 0;
1794 vlog
= smalloc(20 + vslen
);
1795 vstring
[strcspn (vstring
, "\r\n")] = '\0'; /* remove end-of-line chars */
1796 sprintf(vlog
, "Server version: %s", vstring
);
1798 ssh_detect_bugs(vstring
);
1802 * Decide which SSH protocol version to support.
1805 /* Anything strictly below "2.0" means protocol 1 is supported. */
1806 proto1
= ssh_versioncmp(version
, "2.0") < 0;
1807 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1808 proto2
= ssh_versioncmp(version
, "1.99") >= 0;
1810 if (cfg
.sshprot
== 0 && !proto1
) {
1811 bombout(("SSH protocol version 1 required by user but not provided by server"));
1814 if (cfg
.sshprot
== 3 && !proto2
) {
1815 bombout(("SSH protocol version 2 required by user but not provided by server"));
1819 if (proto2
&& (cfg
.sshprot
>= 2 || !proto1
)) {
1823 char verstring
[80], vlog
[100];
1824 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1825 SHA_Init(&exhashbase
);
1827 * Hash our version string and their version string.
1829 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1830 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1831 sprintf(vlog
, "We claim version: %s", verstring
);
1833 strcat(verstring
, "\n");
1834 logevent("Using SSH protocol version 2");
1835 sk_write(s
, verstring
, strlen(verstring
));
1836 ssh_protocol
= ssh2_protocol
;
1838 s_rdpkt
= ssh2_rdpkt
;
1843 char verstring
[80], vlog
[100];
1844 sprintf(verstring
, "SSH-%s-%s",
1845 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"),
1847 sprintf(vlog
, "We claim version: %s", verstring
);
1849 strcat(verstring
, "\n");
1851 logevent("Using SSH protocol version 1");
1852 sk_write(s
, verstring
, strlen(verstring
));
1853 ssh_protocol
= ssh1_protocol
;
1855 s_rdpkt
= ssh1_rdpkt
;
1857 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1864 static void ssh_gotdata(unsigned char *data
, int datalen
)
1869 * To begin with, feed the characters one by one to the
1870 * protocol initialisation / selection function do_ssh_init().
1871 * When that returns 0, we're done with the initial greeting
1872 * exchange and can move on to packet discipline.
1877 crReturnV
; /* more data please */
1878 ret
= do_ssh_init(*data
);
1886 * We emerge from that loop when the initial negotiation is
1887 * over and we have selected an s_rdpkt function. Now pass
1888 * everything to s_rdpkt, and then pass the resulting packets
1889 * to the proper protocol handler.
1894 while (datalen
> 0) {
1895 if (s_rdpkt(&data
, &datalen
) == 0) {
1896 if (ssh_state
== SSH_STATE_CLOSED
) {
1899 ssh_protocol(NULL
, 0, 1);
1900 if (ssh_state
== SSH_STATE_CLOSED
) {
1910 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1913 ssh_state
= SSH_STATE_CLOSED
;
1919 /* A socket error has occurred. */
1920 logevent(error_msg
);
1921 connection_fatal(error_msg
);
1923 /* Otherwise, the remote side closed the connection normally. */
1928 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1930 ssh_gotdata(data
, len
);
1931 if (ssh_state
== SSH_STATE_CLOSED
) {
1941 static void ssh_sent(Plug plug
, int bufsize
)
1944 * If the send backlog on the SSH socket itself clears, we
1945 * should unthrottle the whole world if it was throttled.
1947 if (bufsize
< SSH_MAX_BACKLOG
)
1948 ssh_throttle_all(0, bufsize
);
1952 * Connect to specified host and port.
1953 * Returns an error message, or NULL on success.
1954 * Also places the canonical host name into `realhost'. It must be
1955 * freed by the caller.
1957 static char *connect_to_host(char *host
, int port
, char **realhost
, int nodelay
)
1959 static struct plug_function_table fn_table
= {
1964 }, *fn_table_ptr
= &fn_table
;
1973 savedhost
= smalloc(1 + strlen(host
));
1975 fatalbox("Out of memory");
1976 strcpy(savedhost
, host
);
1979 port
= 22; /* default ssh port */
1994 sprintf(buf
, "Looking up host \"%.170s\"", host
);
1997 addr
= sk_namelookup(host
, realhost
);
1998 if ((err
= sk_addr_error(addr
)))
2002 *realhost
= strdup(FWhost
);
2009 char buf
[200], addrbuf
[100];
2010 sk_getaddr(addr
, addrbuf
, 100);
2011 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
2014 s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, &fn_table_ptr
);
2015 if ((err
= sk_socket_error(s
))) {
2021 sk_write(s
, "connect ", 8);
2022 sk_write(s
, FWhost
, strlen(FWhost
));
2025 sprintf(buf
, " %d\n", FWport
);
2026 sk_write(s
, buf
, strlen(buf
));
2034 * Throttle or unthrottle the SSH connection.
2036 static void ssh1_throttle(int adjust
)
2038 int old_count
= ssh1_throttle_count
;
2039 ssh1_throttle_count
+= adjust
;
2040 assert(ssh1_throttle_count
>= 0);
2041 if (ssh1_throttle_count
&& !old_count
) {
2042 sk_set_frozen(s
, 1);
2043 } else if (!ssh1_throttle_count
&& old_count
) {
2044 sk_set_frozen(s
, 0);
2049 * Throttle or unthrottle _all_ local data streams (for when sends
2050 * on the SSH connection itself back up).
2052 static void ssh_throttle_all(int enable
, int bufsize
)
2055 struct ssh_channel
*c
;
2057 if (enable
== ssh_throttled_all
)
2059 ssh_throttled_all
= enable
;
2060 ssh_overall_bufsize
= bufsize
;
2063 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
2065 case CHAN_MAINSESSION
:
2067 * This is treated separately, outside the switch.
2071 x11_override_throttle(c
->u
.x11
.s
, enable
);
2074 /* Agent channels require no buffer management. */
2077 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2084 * Username and password input, abstracted off into reusable
2085 * routines (hopefully even reusable between SSH1 and SSH2!).
2087 static char *ssh_userpass_input_buffer
;
2088 static int ssh_userpass_input_buflen
;
2089 static int ssh_userpass_input_bufpos
;
2090 static int ssh_userpass_input_echo
;
2092 /* Set up a username or password input loop on a given buffer. */
2093 void setup_userpass_input(char *buffer
, int buflen
, int echo
)
2095 ssh_userpass_input_buffer
= buffer
;
2096 ssh_userpass_input_buflen
= buflen
;
2097 ssh_userpass_input_bufpos
= 0;
2098 ssh_userpass_input_echo
= echo
;
2102 * Process some terminal data in the course of username/password
2103 * input. Returns >0 for success (line of input returned in
2104 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2105 * for inconclusive (keep waiting for more input please).
2107 int process_userpass_input(unsigned char *in
, int inlen
)
2112 switch (c
= *in
++) {
2115 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
] = 0;
2116 ssh_userpass_input_buffer
[ssh_userpass_input_buflen
-1] = 0;
2121 if (ssh_userpass_input_bufpos
> 0) {
2122 if (ssh_userpass_input_echo
)
2123 c_write_str("\b \b");
2124 ssh_userpass_input_bufpos
--;
2129 while (ssh_userpass_input_bufpos
> 0) {
2130 if (ssh_userpass_input_echo
)
2131 c_write_str("\b \b");
2132 ssh_userpass_input_bufpos
--;
2140 if (((c
>= ' ' && c
<= '~') ||
2141 ((unsigned char) c
>= 160))
2142 && ssh_userpass_input_bufpos
< ssh_userpass_input_buflen
-1) {
2143 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
++] = c
;
2144 if (ssh_userpass_input_echo
)
2154 * Handle the key exchange and user authentication phases.
2156 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
2160 static unsigned char *rsabuf
, *keystr1
, *keystr2
;
2161 unsigned char cookie
[8];
2162 struct RSAKey servkey
, hostkey
;
2163 struct MD5Context md5c
;
2164 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
2165 static int tried_publickey
, tried_agent
;
2166 static int tis_auth_refused
, ccard_auth_refused
;
2167 static unsigned char session_id
[16];
2168 static int cipher_type
;
2169 static char username
[100];
2170 static void *publickey_blob
;
2171 int publickey_bloblen
;
2178 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2179 bombout(("Public key packet not received"));
2183 logevent("Received public keys");
2185 memcpy(cookie
, pktin
.body
, 8);
2187 i
= makekey(pktin
.body
+ 8, &servkey
, &keystr1
, 0);
2188 j
= makekey(pktin
.body
+ 8 + i
, &hostkey
, &keystr2
, 0);
2191 * Log the host key fingerprint.
2195 logevent("Host key fingerprint is:");
2196 strcpy(logmsg
, " ");
2197 hostkey
.comment
= NULL
;
2198 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2199 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2203 ssh1_remote_protoflags
= GET_32BIT(pktin
.body
+ 8 + i
+ j
);
2204 supported_ciphers_mask
= GET_32BIT(pktin
.body
+ 12 + i
+ j
);
2205 supported_auths_mask
= GET_32BIT(pktin
.body
+ 16 + i
+ j
);
2207 ssh1_local_protoflags
=
2208 ssh1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2209 ssh1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2212 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
2213 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
2214 MD5Update(&md5c
, pktin
.body
, 8);
2215 MD5Final(session_id
, &md5c
);
2217 for (i
= 0; i
< 32; i
++)
2218 session_key
[i
] = random_byte();
2220 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2222 rsabuf
= smalloc(len
);
2224 fatalbox("Out of memory");
2227 * Verify the host key.
2231 * First format the key into a string.
2233 int len
= rsastr_len(&hostkey
);
2234 char fingerprint
[100];
2235 char *keystr
= smalloc(len
);
2237 fatalbox("Out of memory");
2238 rsastr_fmt(keystr
, &hostkey
);
2239 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2240 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
,
2245 for (i
= 0; i
< 32; i
++) {
2246 rsabuf
[i
] = session_key
[i
];
2248 rsabuf
[i
] ^= session_id
[i
];
2251 if (hostkey
.bytes
> servkey
.bytes
) {
2252 rsaencrypt(rsabuf
, 32, &servkey
);
2253 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
2255 rsaencrypt(rsabuf
, 32, &hostkey
);
2256 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
2259 logevent("Encrypted session key");
2262 int cipher_chosen
= 0, warn
= 0;
2263 char *cipher_string
= NULL
;
2264 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2265 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2266 if (next_cipher
== CIPHER_WARN
) {
2267 /* If/when we choose a cipher, warn about it */
2269 } else if (next_cipher
== CIPHER_AES
) {
2270 /* XXX Probably don't need to mention this. */
2271 logevent("AES not supported in SSH1, skipping");
2273 switch (next_cipher
) {
2274 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
;
2275 cipher_string
= "3DES"; break;
2276 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
;
2277 cipher_string
= "Blowfish"; break;
2278 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
;
2279 cipher_string
= "single-DES"; break;
2281 if (supported_ciphers_mask
& (1 << cipher_type
))
2285 if (!cipher_chosen
) {
2286 if ((supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2287 bombout(("Server violates SSH 1 protocol by not "
2288 "supporting 3DES encryption"));
2290 /* shouldn't happen */
2291 bombout(("No supported ciphers found"));
2295 /* Warn about chosen cipher if necessary. */
2297 askcipher(cipher_string
, 0);
2300 switch (cipher_type
) {
2301 case SSH_CIPHER_3DES
:
2302 logevent("Using 3DES encryption");
2304 case SSH_CIPHER_DES
:
2305 logevent("Using single-DES encryption");
2307 case SSH_CIPHER_BLOWFISH
:
2308 logevent("Using Blowfish encryption");
2312 send_packet(SSH1_CMSG_SESSION_KEY
,
2313 PKT_CHAR
, cipher_type
,
2314 PKT_DATA
, cookie
, 8,
2315 PKT_CHAR
, (len
* 8) >> 8, PKT_CHAR
, (len
* 8) & 0xFF,
2316 PKT_DATA
, rsabuf
, len
,
2317 PKT_INT
, ssh1_local_protoflags
, PKT_END
);
2319 logevent("Trying to enable encryption...");
2323 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2324 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
: &ssh_3des
;
2325 cipher
->sesskey(session_key
);
2329 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2330 bombout(("Encryption not successfully enabled"));
2334 logevent("Successfully started encryption");
2338 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2339 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2340 if (!ssh_get_line("login as: ",
2341 username
, sizeof(username
), FALSE
)) {
2343 * get_line failed to get a username.
2346 logevent("No username provided. Abandoning session.");
2347 ssh_state
= SSH_STATE_CLOSED
;
2352 c_write_str("login as: ");
2355 setup_userpass_input(username
, sizeof(username
), 1);
2357 crWaitUntil(!ispkt
);
2358 ret
= process_userpass_input(in
, inlen
);
2362 c_write_str("\r\n");
2365 strncpy(username
, cfg
.username
, 99);
2366 username
[99] = '\0';
2369 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
2371 char userlog
[22 + sizeof(username
)];
2372 sprintf(userlog
, "Sent username \"%s\"", username
);
2374 if (flags
& FLAG_INTERACTIVE
&&
2375 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2376 strcat(userlog
, "\r\n");
2377 c_write_str(userlog
);
2384 if ((ssh_remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2385 /* We must not attempt PK auth. Pretend we've already tried it. */
2386 tried_publickey
= tried_agent
= 1;
2388 tried_publickey
= tried_agent
= 0;
2390 tis_auth_refused
= ccard_auth_refused
= 0;
2391 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2393 if (!rsakey_pubblob(cfg
.keyfile
, &publickey_blob
, &publickey_bloblen
))
2394 publickey_blob
= NULL
;
2396 publickey_blob
= NULL
;
2398 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
2399 static char password
[100];
2400 static char prompt
[200];
2403 static int pwpkt_type
;
2404 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2406 if (agent_exists() && !tried_agent
) {
2408 * Attempt RSA authentication using Pageant.
2410 static unsigned char request
[5], *response
, *p
;
2411 static int responselen
;
2412 static int i
, nkeys
;
2413 static int authed
= FALSE
;
2417 logevent("Pageant is running. Requesting keys.");
2419 /* Request the keys held by the agent. */
2420 PUT_32BIT(request
, 1);
2421 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2422 agent_query(request
, 5, &r
, &responselen
);
2423 response
= (unsigned char *) r
;
2424 if (response
&& responselen
>= 5 &&
2425 response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2427 nkeys
= GET_32BIT(p
);
2431 sprintf(buf
, "Pageant has %d SSH1 keys", nkeys
);
2434 for (i
= 0; i
< nkeys
; i
++) {
2435 static struct RSAKey key
;
2436 static Bignum challenge
;
2437 static char *commentp
;
2438 static int commentlen
;
2442 sprintf(buf
, "Trying Pageant key #%d", i
);
2445 if (publickey_blob
&&
2446 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
2447 logevent("This key matches configured key file");
2448 tried_publickey
= 1;
2451 p
+= ssh1_read_bignum(p
, &key
.exponent
);
2452 p
+= ssh1_read_bignum(p
, &key
.modulus
);
2453 commentlen
= GET_32BIT(p
);
2457 send_packet(SSH1_CMSG_AUTH_RSA
,
2458 PKT_BIGNUM
, key
.modulus
, PKT_END
);
2460 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2461 logevent("Key refused");
2464 logevent("Received RSA challenge");
2465 ssh1_read_bignum(pktin
.body
, &challenge
);
2467 char *agentreq
, *q
, *ret
;
2470 len
= 1 + 4; /* message type, bit count */
2471 len
+= ssh1_bignum_length(key
.exponent
);
2472 len
+= ssh1_bignum_length(key
.modulus
);
2473 len
+= ssh1_bignum_length(challenge
);
2474 len
+= 16; /* session id */
2475 len
+= 4; /* response format */
2476 agentreq
= smalloc(4 + len
);
2477 PUT_32BIT(agentreq
, len
);
2479 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2480 PUT_32BIT(q
, bignum_bitcount(key
.modulus
));
2482 q
+= ssh1_write_bignum(q
, key
.exponent
);
2483 q
+= ssh1_write_bignum(q
, key
.modulus
);
2484 q
+= ssh1_write_bignum(q
, challenge
);
2485 memcpy(q
, session_id
, 16);
2487 PUT_32BIT(q
, 1); /* response format */
2488 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2492 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2493 logevent("Sending Pageant's response");
2494 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2495 PKT_DATA
, ret
+ 5, 16,
2499 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2501 ("Pageant's response accepted");
2502 if (flags
& FLAG_VERBOSE
) {
2504 ("Authenticated using RSA key \"");
2505 c_write(commentp
, commentlen
);
2506 c_write_str("\" from agent\r\n");
2511 ("Pageant's response not accepted");
2514 ("Pageant failed to answer challenge");
2518 logevent("No reply received from Pageant");
2521 freebn(key
.exponent
);
2522 freebn(key
.modulus
);
2531 if (*cfg
.keyfile
&& !tried_publickey
)
2532 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2534 if (cfg
.try_tis_auth
&&
2535 (supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2536 !tis_auth_refused
) {
2537 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2538 logevent("Requested TIS authentication");
2539 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
2541 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2542 logevent("TIS authentication declined");
2543 if (flags
& FLAG_INTERACTIVE
)
2544 c_write_str("TIS authentication refused.\r\n");
2545 tis_auth_refused
= 1;
2548 int challengelen
= ((pktin
.body
[0] << 24) |
2549 (pktin
.body
[1] << 16) |
2550 (pktin
.body
[2] << 8) |
2552 logevent("Received TIS challenge");
2553 if (challengelen
> sizeof(prompt
) - 1)
2554 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2555 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2556 /* Prompt heuristic comes from OpenSSH */
2557 strncpy(prompt
+ challengelen
,
2558 memchr(prompt
, '\n', challengelen
) ?
2559 "": "\r\nResponse: ",
2560 (sizeof prompt
) - challengelen
);
2561 prompt
[(sizeof prompt
) - 1] = '\0';
2564 if (cfg
.try_tis_auth
&&
2565 (supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2566 !ccard_auth_refused
) {
2567 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2568 logevent("Requested CryptoCard authentication");
2569 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2571 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2572 logevent("CryptoCard authentication declined");
2573 c_write_str("CryptoCard authentication refused.\r\n");
2574 ccard_auth_refused
= 1;
2577 int challengelen
= ((pktin
.body
[0] << 24) |
2578 (pktin
.body
[1] << 16) |
2579 (pktin
.body
[2] << 8) |
2581 logevent("Received CryptoCard challenge");
2582 if (challengelen
> sizeof(prompt
) - 1)
2583 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2584 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2585 strncpy(prompt
+ challengelen
,
2586 memchr(prompt
, '\n', challengelen
) ?
2587 "" : "\r\nResponse: ",
2588 sizeof(prompt
) - challengelen
);
2589 prompt
[sizeof(prompt
) - 1] = '\0';
2592 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2593 sprintf(prompt
, "%.90s@%.90s's password: ",
2594 username
, savedhost
);
2596 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2597 char *comment
= NULL
;
2600 if (flags
& FLAG_VERBOSE
)
2601 c_write_str("Trying public key authentication.\r\n");
2602 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2604 type
= key_type(cfg
.keyfile
);
2605 if (type
!= SSH_KEYTYPE_SSH1
) {
2606 sprintf(msgbuf
, "Key is of wrong type (%s)",
2607 key_type_to_str(type
));
2609 c_write_str(msgbuf
);
2610 c_write_str("\r\n");
2611 tried_publickey
= 1;
2614 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2615 if (flags
& FLAG_VERBOSE
)
2616 c_write_str("No passphrase required.\r\n");
2619 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
2624 * Show password prompt, having first obtained it via a TIS
2625 * or CryptoCard exchange if we're doing TIS or CryptoCard
2629 if (!ssh_get_line(prompt
, password
, sizeof(password
), TRUE
)) {
2631 * get_line failed to get a password (for example
2632 * because one was supplied on the command line
2633 * which has already failed to work). Terminate.
2635 send_packet(SSH1_MSG_DISCONNECT
,
2636 PKT_STR
, "No more passwords available to try",
2638 logevent("Unable to authenticate");
2639 connection_fatal("Unable to authenticate");
2640 ssh_state
= SSH_STATE_CLOSED
;
2644 /* Prompt may have come from server. We've munged it a bit, so
2645 * we know it to be zero-terminated at least once. */
2647 c_write_untrusted(prompt
, strlen(prompt
));
2650 setup_userpass_input(password
, sizeof(password
), 0);
2652 crWaitUntil(!ispkt
);
2653 ret
= process_userpass_input(in
, inlen
);
2657 c_write_str("\r\n");
2661 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2663 * Try public key authentication with the specified
2666 static struct RSAKey pubkey
;
2667 static Bignum challenge
, response
;
2669 static unsigned char buffer
[32];
2671 tried_publickey
= 1;
2672 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
2674 c_write_str("Couldn't load private key from ");
2675 c_write_str(cfg
.keyfile
);
2676 c_write_str(".\r\n");
2677 continue; /* go and try password */
2680 c_write_str("Wrong passphrase.\r\n");
2681 tried_publickey
= 0;
2682 continue; /* try again */
2686 * Send a public key attempt.
2688 send_packet(SSH1_CMSG_AUTH_RSA
,
2689 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
2692 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2693 c_write_str("Server refused our public key.\r\n");
2694 continue; /* go and try password */
2696 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2697 bombout(("Bizarre response to offer of public key"));
2700 ssh1_read_bignum(pktin
.body
, &challenge
);
2701 response
= rsadecrypt(challenge
, &pubkey
);
2702 freebn(pubkey
.private_exponent
); /* burn the evidence */
2704 for (i
= 0; i
< 32; i
++) {
2705 buffer
[i
] = bignum_byte(response
, 31 - i
);
2709 MD5Update(&md5c
, buffer
, 32);
2710 MD5Update(&md5c
, session_id
, 16);
2711 MD5Final(buffer
, &md5c
);
2713 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2714 PKT_DATA
, buffer
, 16, PKT_END
);
2717 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2718 if (flags
& FLAG_VERBOSE
)
2720 ("Failed to authenticate with our public key.\r\n");
2721 continue; /* go and try password */
2722 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2724 ("Bizarre response to RSA authentication response"));
2728 break; /* we're through! */
2730 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2732 * Defence against traffic analysis: we send a
2733 * whole bunch of packets containing strings of
2734 * different lengths. One of these strings is the
2735 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2736 * The others are all random data in
2737 * SSH1_MSG_IGNORE packets. This way a passive
2738 * listener can't tell which is the password, and
2739 * hence can't deduce the password length.
2741 * Anybody with a password length greater than 16
2742 * bytes is going to have enough entropy in their
2743 * password that a listener won't find it _that_
2744 * much help to know how long it is. So what we'll
2747 * - if password length < 16, we send 15 packets
2748 * containing string lengths 1 through 15
2750 * - otherwise, we let N be the nearest multiple
2751 * of 8 below the password length, and send 8
2752 * packets containing string lengths N through
2753 * N+7. This won't obscure the order of
2754 * magnitude of the password length, but it will
2755 * introduce a bit of extra uncertainty.
2757 * A few servers (the old 1.2.18 through 1.2.22)
2758 * can't deal with SSH1_MSG_IGNORE. For these
2759 * servers, we need an alternative defence. We make
2760 * use of the fact that the password is interpreted
2761 * as a C string: so we can append a NUL, then some
2764 * One server (a Cisco one) can deal with neither
2765 * SSH1_MSG_IGNORE _nor_ a padded password string.
2766 * For this server we are left with no defences
2767 * against password length sniffing.
2769 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2771 * The server can deal with SSH1_MSG_IGNORE, so
2772 * we can use the primary defence.
2774 int bottom
, top
, pwlen
, i
;
2777 pwlen
= strlen(password
);
2779 bottom
= 0; /* zero length passwords are OK! :-) */
2782 bottom
= pwlen
& ~7;
2786 assert(pwlen
>= bottom
&& pwlen
<= top
);
2788 randomstr
= smalloc(top
+ 1);
2790 for (i
= bottom
; i
<= top
; i
++) {
2792 defer_packet(pwpkt_type
, PKT_STR
, password
,
2795 for (j
= 0; j
< i
; j
++) {
2797 randomstr
[j
] = random_byte();
2798 } while (randomstr
[j
] == '\0');
2800 randomstr
[i
] = '\0';
2801 defer_packet(SSH1_MSG_IGNORE
,
2802 PKT_STR
, randomstr
, PKT_END
);
2805 logevent("Sending password with camouflage packets");
2806 ssh_pkt_defersend();
2808 else if (!(ssh_remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2810 * The server can't deal with SSH1_MSG_IGNORE
2811 * but can deal with padded passwords, so we
2812 * can use the secondary defence.
2818 len
= strlen(password
);
2819 if (len
< sizeof(string
)) {
2821 strcpy(string
, password
);
2822 len
++; /* cover the zero byte */
2823 while (len
< sizeof(string
)) {
2824 string
[len
++] = (char) random_byte();
2829 logevent("Sending length-padded password");
2830 send_packet(pwpkt_type
, PKT_INT
, len
,
2831 PKT_DATA
, s
, len
, PKT_END
);
2834 * The server has _both_
2835 * BUG_CHOKES_ON_SSH1_IGNORE and
2836 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2837 * therefore nothing we can do.
2840 len
= strlen(password
);
2841 logevent("Sending unpadded password");
2842 send_packet(pwpkt_type
, PKT_INT
, len
,
2843 PKT_DATA
, password
, len
, PKT_END
);
2846 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
2849 logevent("Sent password");
2850 memset(password
, 0, strlen(password
));
2852 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2853 if (flags
& FLAG_VERBOSE
)
2854 c_write_str("Access denied\r\n");
2855 logevent("Authentication refused");
2856 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2857 logevent("Received disconnect request");
2858 ssh_state
= SSH_STATE_CLOSED
;
2860 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2861 bombout(("Strange packet received, type %d", pktin
.type
));
2866 logevent("Authentication successful");
2871 void sshfwd_close(struct ssh_channel
*c
)
2873 if (c
&& !c
->closes
) {
2875 * If the channel's remoteid is -1, we have sent
2876 * CHANNEL_OPEN for this channel, but it hasn't even been
2877 * acknowledged by the server. So we must set a close flag
2878 * on it now, and then when the server acks the channel
2879 * open, we can close it then.
2881 if (((int)c
->remoteid
) != -1) {
2882 if (ssh_version
== 1) {
2883 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2886 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2887 ssh2_pkt_adduint32(c
->remoteid
);
2892 if (c
->type
== CHAN_X11
) {
2894 logevent("Forwarded X11 connection terminated");
2895 } else if (c
->type
== CHAN_SOCKDATA
||
2896 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2898 logevent("Forwarded port closed");
2903 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2905 if (ssh_version
== 1) {
2906 send_packet(SSH1_MSG_CHANNEL_DATA
,
2907 PKT_INT
, c
->remoteid
,
2908 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2910 * In SSH1 we can return 0 here - implying that forwarded
2911 * connections are never individually throttled - because
2912 * the only circumstance that can cause throttling will be
2913 * the whole SSH connection backing up, in which case
2914 * _everything_ will be throttled as a whole.
2918 ssh2_add_channel_data(c
, buf
, len
);
2919 return ssh2_try_send(c
);
2923 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2925 if (ssh_version
== 1) {
2926 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2927 c
->v
.v1
.throttling
= 0;
2931 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
2935 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
)
2941 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
2944 if (ssh_state
== SSH_STATE_CLOSED
)
2947 if (cfg
.agentfwd
&& agent_exists()) {
2948 logevent("Requesting agent forwarding");
2949 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
2953 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2954 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2955 bombout(("Protocol confusion"));
2957 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2958 logevent("Agent forwarding refused");
2960 logevent("Agent forwarding enabled");
2961 ssh_agentfwd_enabled
= TRUE
;
2965 if (cfg
.x11_forward
) {
2966 char proto
[20], data
[64];
2967 logevent("Requesting X11 forwarding");
2968 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2969 if (ssh1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
2970 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2971 PKT_STR
, proto
, PKT_STR
, data
,
2972 PKT_INT
, 0, PKT_END
);
2974 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2975 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
2980 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2981 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2982 bombout(("Protocol confusion"));
2984 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2985 logevent("X11 forwarding refused");
2987 logevent("X11 forwarding enabled");
2988 ssh_X11_fwd_enabled
= TRUE
;
2996 int sport
,dport
,sserv
,dserv
;
2997 char sports
[256], dports
[256], host
[256];
3001 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3002 /* Add port forwardings. */
3007 while (*e
&& *e
!= '\t')
3013 while (*e
&& *e
!= ':')
3023 dport
= atoi(dports
);
3027 se
= getservbyname(dports
, NULL
);
3029 dport
= ntohs(se
->s_port
);
3032 "Service lookup failed for destination port \"%s\"",
3037 sport
= atoi(sports
);
3041 se
= getservbyname(sports
, NULL
);
3043 sport
= ntohs(se
->s_port
);
3046 "Service lookup failed for source port \"%s\"",
3051 if (sport
&& dport
) {
3053 pfd_addforward(host
, dport
, sport
);
3054 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3055 " %s:%.*s%.*s%d%.*s",
3056 sserv ?
strlen(sports
) : 0, sports
,
3057 sserv
, "(", sport
, sserv
, ")",
3059 dserv ?
strlen(dports
) : 0, dports
,
3060 dserv
, "(", dport
, dserv
, ")");
3063 struct ssh_rportfwd
*pf
;
3064 pf
= smalloc(sizeof(*pf
));
3065 strcpy(pf
->dhost
, host
);
3067 if (add234(ssh_rportfwds
, pf
) != pf
) {
3069 "Duplicate remote port forwarding to %s:%d",
3074 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3075 " forward to %s:%.*s%.*s%d%.*s",
3076 sserv ?
strlen(sports
) : 0, sports
,
3077 sserv
, "(", sport
, sserv
, ")",
3079 dserv ?
strlen(dports
) : 0, dports
,
3080 dserv
, "(", dport
, dserv
, ")");
3082 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST
,
3090 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3091 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3092 bombout(("Protocol confusion"));
3094 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3095 c_write_str("Server refused port forwarding\r\n");
3096 ssh_editing
= ssh_echoing
= 1;
3098 logevent("Remote port forwarding enabled");
3106 send_packet(SSH1_CMSG_REQUEST_PTY
,
3107 PKT_STR
, cfg
.termtype
,
3108 PKT_INT
, rows
, PKT_INT
, cols
,
3109 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3110 ssh_state
= SSH_STATE_INTERMED
;
3114 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3115 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3116 bombout(("Protocol confusion"));
3118 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3119 c_write_str("Server refused to allocate pty\r\n");
3120 ssh_editing
= ssh_echoing
= 1;
3122 logevent("Allocated pty");
3124 ssh_editing
= ssh_echoing
= 1;
3127 if (cfg
.compression
) {
3128 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3132 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3133 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3134 bombout(("Protocol confusion"));
3136 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3137 c_write_str("Server refused to compress\r\n");
3139 logevent("Started compression");
3140 ssh1_compressing
= TRUE
;
3141 zlib_compress_init();
3142 zlib_decompress_init();
3146 * Start the shell or command.
3148 * Special case: if the first-choice command is an SSH2
3149 * subsystem (hence not usable here) and the second choice
3150 * exists, we fall straight back to that.
3153 char *cmd
= cfg
.remote_cmd_ptr
;
3155 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3156 cmd
= cfg
.remote_cmd_ptr2
;
3157 ssh_fallback_cmd
= TRUE
;
3160 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3162 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3163 logevent("Started session");
3166 ssh_state
= SSH_STATE_SESSION
;
3170 ssh_special(TS_EOF
);
3172 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
3174 ssh_channels
= newtree234(ssh_channelcmp
);
3178 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3179 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3180 long len
= GET_32BIT(pktin
.body
);
3182 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3183 pktin
.body
+ 4, len
);
3184 if (!ssh1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3185 ssh1_stdout_throttling
= 1;
3188 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
3189 ssh_state
= SSH_STATE_CLOSED
;
3190 logevent("Received disconnect request");
3192 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3193 /* Remote side is trying to open a channel to talk to our
3194 * X-Server. Give them back a local channel number. */
3195 struct ssh_channel
*c
;
3197 logevent("Received X11 connect request");
3198 /* Refuse if X11 forwarding is disabled. */
3199 if (!ssh_X11_fwd_enabled
) {
3200 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3201 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3202 logevent("Rejected X11 connect request");
3204 c
= smalloc(sizeof(struct ssh_channel
));
3206 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3207 logevent("opening X11 forward connection failed");
3209 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3210 PKT_INT
, GET_32BIT(pktin
.body
),
3214 ("opening X11 forward connection succeeded");
3215 c
->remoteid
= GET_32BIT(pktin
.body
);
3216 c
->localid
= alloc_channel_id();
3218 c
->v
.v1
.throttling
= 0;
3219 c
->type
= CHAN_X11
; /* identify channel type */
3220 add234(ssh_channels
, c
);
3221 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3222 PKT_INT
, c
->remoteid
, PKT_INT
,
3223 c
->localid
, PKT_END
);
3224 logevent("Opened X11 forward channel");
3227 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3228 /* Remote side is trying to open a channel to talk to our
3229 * agent. Give them back a local channel number. */
3230 struct ssh_channel
*c
;
3232 /* Refuse if agent forwarding is disabled. */
3233 if (!ssh_agentfwd_enabled
) {
3234 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3235 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3237 c
= smalloc(sizeof(struct ssh_channel
));
3238 c
->remoteid
= GET_32BIT(pktin
.body
);
3239 c
->localid
= alloc_channel_id();
3241 c
->v
.v1
.throttling
= 0;
3242 c
->type
= CHAN_AGENT
; /* identify channel type */
3243 c
->u
.a
.lensofar
= 0;
3244 add234(ssh_channels
, c
);
3245 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3246 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3249 } else if (pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3250 /* Remote side is trying to open a channel to talk to a
3251 * forwarded port. Give them back a local channel number. */
3252 struct ssh_channel
*c
;
3253 struct ssh_rportfwd pf
;
3255 char host
[256], buf
[1024];
3257 c
= smalloc(sizeof(struct ssh_channel
));
3259 hostsize
= GET_32BIT(pktin
.body
+4);
3260 for(h
= host
, p
= pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3261 if (h
+1 < host
+sizeof(host
))
3266 port
= GET_32BIT(p
);
3268 strcpy(pf
.dhost
, host
);
3271 if (find234(ssh_rportfwds
, &pf
, NULL
) == NULL
) {
3272 sprintf(buf
, "Rejected remote port open request for %s:%d",
3275 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3276 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3278 sprintf(buf
, "Received remote port open request for %s:%d",
3281 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3284 sprintf(buf
, "Port open failed: %s", e
);
3287 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3288 PKT_INT
, GET_32BIT(pktin
.body
),
3291 c
->remoteid
= GET_32BIT(pktin
.body
);
3292 c
->localid
= alloc_channel_id();
3294 c
->v
.v1
.throttling
= 0;
3295 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3296 add234(ssh_channels
, c
);
3297 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3298 PKT_INT
, c
->remoteid
, PKT_INT
,
3299 c
->localid
, PKT_END
);
3300 logevent("Forwarded port opened successfully");
3304 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3305 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3306 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3307 struct ssh_channel
*c
;
3309 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3310 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3311 c
->remoteid
= localid
;
3312 c
->type
= CHAN_SOCKDATA
;
3313 c
->v
.v1
.throttling
= 0;
3314 pfd_confirm(c
->u
.pfd
.s
);
3317 if (c
&& c
->closes
) {
3319 * We have a pending close on this channel,
3320 * which we decided on before the server acked
3321 * the channel open. So now we know the
3322 * remoteid, we can close it again.
3324 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3328 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3329 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3330 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3331 struct ssh_channel
*c
;
3333 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3334 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3335 logevent("Forwarded connection refused by server");
3336 pfd_close(c
->u
.pfd
.s
);
3337 del234(ssh_channels
, c
);
3341 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3342 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3343 /* Remote side closes a channel. */
3344 unsigned i
= GET_32BIT(pktin
.body
);
3345 struct ssh_channel
*c
;
3346 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3350 (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3351 if (!(c
->closes
& closetype
))
3352 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
,
3354 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3355 logevent("Forwarded X11 connection terminated");
3356 assert(c
->u
.x11
.s
!= NULL
);
3357 x11_close(c
->u
.x11
.s
);
3360 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3361 logevent("Forwarded port closed");
3362 assert(c
->u
.pfd
.s
!= NULL
);
3363 pfd_close(c
->u
.pfd
.s
);
3366 c
->closes
|= closetype
;
3367 if (c
->closes
== 3) {
3368 del234(ssh_channels
, c
);
3372 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3373 /* Data sent down one of our channels. */
3374 int i
= GET_32BIT(pktin
.body
);
3375 int len
= GET_32BIT(pktin
.body
+ 4);
3376 unsigned char *p
= pktin
.body
+ 8;
3377 struct ssh_channel
*c
;
3378 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3383 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3386 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3389 /* Data for an agent message. Buffer it. */
3391 if (c
->u
.a
.lensofar
< 4) {
3392 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3393 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3397 c
->u
.a
.lensofar
+= l
;
3399 if (c
->u
.a
.lensofar
== 4) {
3401 4 + GET_32BIT(c
->u
.a
.msglen
);
3402 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3403 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3405 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3407 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3409 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3413 c
->u
.a
.lensofar
+= l
;
3415 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3416 void *reply
, *sentreply
;
3418 agent_query(c
->u
.a
.message
,
3419 c
->u
.a
.totallen
, &reply
,
3424 /* Fake SSH_AGENT_FAILURE. */
3425 sentreply
= "\0\0\0\1\5";
3428 send_packet(SSH1_MSG_CHANNEL_DATA
,
3429 PKT_INT
, c
->remoteid
,
3431 PKT_DATA
, sentreply
, replylen
,
3435 sfree(c
->u
.a
.message
);
3436 c
->u
.a
.lensofar
= 0;
3439 bufsize
= 0; /* agent channels never back up */
3442 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3443 c
->v
.v1
.throttling
= 1;
3447 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
3448 /* may be from EXEC_SHELL on some servers */
3449 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3450 /* may be from EXEC_SHELL on some servers
3451 * if no pty is available or in other odd cases. Ignore */
3452 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3454 ssh_exitcode
= GET_32BIT(pktin
.body
);
3455 sprintf(buf
, "Server sent command exit status %d",
3458 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3460 * In case `helpful' firewalls or proxies tack
3461 * extra human-readable text on the end of the
3462 * session which we might mistake for another
3463 * encrypted packet, we close the session once
3464 * we've sent EXIT_CONFIRMATION.
3466 ssh_state
= SSH_STATE_CLOSED
;
3469 bombout(("Strange packet received: type %d", pktin
.type
));
3474 int len
= min(inlen
, 512);
3475 send_packet(SSH1_CMSG_STDIN_DATA
,
3476 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3487 * Utility routine for decoding comma-separated strings in KEXINIT.
3489 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3491 int needlen
= strlen(needle
);
3494 * Is it at the start of the string?
3496 if (haylen
>= needlen
&& /* haystack is long enough */
3497 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3498 (haylen
== needlen
|| haystack
[needlen
] == ',')
3499 /* either , or EOS follows */
3503 * If not, search for the next comma and resume after that.
3504 * If no comma found, terminate.
3506 while (haylen
> 0 && *haystack
!= ',')
3507 haylen
--, haystack
++;
3510 haylen
--, haystack
++; /* skip over comma itself */
3515 * SSH2 key creation method.
3517 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
,
3521 /* First 20 bytes. */
3523 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3525 SHA_Bytes(&s
, H
, 20);
3526 SHA_Bytes(&s
, &chr
, 1);
3527 SHA_Bytes(&s
, sessid
, 20);
3528 SHA_Final(&s
, keyspace
);
3529 /* Next 20 bytes. */
3531 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3533 SHA_Bytes(&s
, H
, 20);
3534 SHA_Bytes(&s
, keyspace
, 20);
3535 SHA_Final(&s
, keyspace
+ 20);
3539 * Handle the SSH2 transport layer.
3541 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
3543 static int i
, j
, len
, nbits
, pbits
, warn
;
3545 static Bignum p
, g
, e
, f
, K
;
3546 static int kex_init_value
, kex_reply_value
;
3547 static const struct ssh_mac
**maclist
;
3549 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
3550 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
3551 static const struct ssh_mac
*csmac_tobe
= NULL
;
3552 static const struct ssh_mac
*scmac_tobe
= NULL
;
3553 static const struct ssh_compress
*cscomp_tobe
= NULL
;
3554 static const struct ssh_compress
*sccomp_tobe
= NULL
;
3555 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3556 static int hostkeylen
, siglen
;
3557 static void *hkey
; /* actual host key */
3558 static unsigned char exchange_hash
[20];
3559 static unsigned char keyspace
[40];
3560 static int n_preferred_ciphers
;
3561 static const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3562 static const struct ssh_compress
*preferred_comp
;
3563 static int cipherstr_started
;
3564 static int first_kex
;
3571 * Set up the preferred ciphers. (NULL => warn below here)
3573 n_preferred_ciphers
= 0;
3574 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3575 switch (cfg
.ssh_cipherlist
[i
]) {
3576 case CIPHER_BLOWFISH
:
3577 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_blowfish
;
3578 n_preferred_ciphers
++;
3581 if (cfg
.ssh2_des_cbc
) {
3582 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_des
;
3583 n_preferred_ciphers
++;
3587 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_3des
;
3588 n_preferred_ciphers
++;
3591 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_aes
;
3592 n_preferred_ciphers
++;
3595 /* Flag for later. Don't bother if it's the last in
3597 if (i
< CIPHER_MAX
- 1) {
3598 preferred_ciphers
[n_preferred_ciphers
] = NULL
;
3599 n_preferred_ciphers
++;
3606 * Set up preferred compression.
3608 if (cfg
.compression
)
3609 preferred_comp
= &ssh_zlib
;
3611 preferred_comp
= &ssh_comp_none
;
3614 * Be prepared to work around the buggy MAC problem.
3616 if (cfg
.buggymac
|| (ssh_remote_bugs
& BUG_SSH2_HMAC
))
3617 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
3619 maclist
= macs
, nmacs
= lenof(macs
);
3623 * Construct and send our key exchange packet.
3625 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
3626 for (i
= 0; i
< 16; i
++)
3627 ssh2_pkt_addbyte((unsigned char) random_byte());
3628 /* List key exchange algorithms. */
3629 ssh2_pkt_addstring_start();
3630 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3631 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
3632 if (i
< lenof(kex_algs
) - 1)
3633 ssh2_pkt_addstring_str(",");
3635 /* List server host key algorithms. */
3636 ssh2_pkt_addstring_start();
3637 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3638 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
3639 if (i
< lenof(hostkey_algs
) - 1)
3640 ssh2_pkt_addstring_str(",");
3642 /* List client->server encryption algorithms. */
3643 ssh2_pkt_addstring_start();
3644 cipherstr_started
= 0;
3645 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3646 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3647 if (!c
) continue; /* warning flag */
3648 for (j
= 0; j
< c
->nciphers
; j
++) {
3649 if (cipherstr_started
)
3650 ssh2_pkt_addstring_str(",");
3651 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3652 cipherstr_started
= 1;
3655 /* List server->client encryption algorithms. */
3656 ssh2_pkt_addstring_start();
3657 cipherstr_started
= 0;
3658 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3659 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3660 if (!c
) continue; /* warning flag */
3661 for (j
= 0; j
< c
->nciphers
; j
++) {
3662 if (cipherstr_started
)
3663 ssh2_pkt_addstring_str(",");
3664 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3665 cipherstr_started
= 1;
3668 /* List client->server MAC algorithms. */
3669 ssh2_pkt_addstring_start();
3670 for (i
= 0; i
< nmacs
; i
++) {
3671 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3673 ssh2_pkt_addstring_str(",");
3675 /* List server->client MAC algorithms. */
3676 ssh2_pkt_addstring_start();
3677 for (i
= 0; i
< nmacs
; i
++) {
3678 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3680 ssh2_pkt_addstring_str(",");
3682 /* List client->server compression algorithms. */
3683 ssh2_pkt_addstring_start();
3684 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3685 const struct ssh_compress
*c
=
3686 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3687 ssh2_pkt_addstring_str(c
->name
);
3688 if (i
< lenof(compressions
))
3689 ssh2_pkt_addstring_str(",");
3691 /* List server->client compression algorithms. */
3692 ssh2_pkt_addstring_start();
3693 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3694 const struct ssh_compress
*c
=
3695 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3696 ssh2_pkt_addstring_str(c
->name
);
3697 if (i
< lenof(compressions
))
3698 ssh2_pkt_addstring_str(",");
3700 /* List client->server languages. Empty list. */
3701 ssh2_pkt_addstring_start();
3702 /* List server->client languages. Empty list. */
3703 ssh2_pkt_addstring_start();
3704 /* First KEX packet does _not_ follow, because we're not that brave. */
3705 ssh2_pkt_addbool(FALSE
);
3707 ssh2_pkt_adduint32(0);
3709 exhash
= exhashbase
;
3710 sha_string(&exhash
, pktout
.data
+ 5, pktout
.length
- 5);
3716 sha_string(&exhash
, pktin
.data
+ 5, pktin
.length
- 5);
3719 * Now examine the other side's KEXINIT to see what we're up
3722 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
3723 bombout(("expected key exchange packet from server"));
3728 cscipher_tobe
= NULL
;
3729 sccipher_tobe
= NULL
;
3734 pktin
.savedpos
+= 16; /* skip garbage cookie */
3735 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
3736 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3737 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3742 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
3743 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3744 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3745 hostkey
= hostkey_algs
[i
];
3749 ssh2_pkt_getstring(&str
, &len
); /* client->server 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 cscipher_tobe
= c
->list
[j
];
3763 if (cscipher_tobe
) {
3765 askcipher(cscipher_tobe
->name
, 1);
3769 if (!cscipher_tobe
) {
3770 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3774 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
3776 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3777 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3781 for (j
= 0; j
< c
->nciphers
; j
++) {
3782 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3783 sccipher_tobe
= c
->list
[j
];
3788 if (sccipher_tobe
) {
3790 askcipher(sccipher_tobe
->name
, 2);
3794 if (!sccipher_tobe
) {
3795 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3799 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
3800 for (i
= 0; i
< nmacs
; i
++) {
3801 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3802 csmac_tobe
= maclist
[i
];
3806 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
3807 for (i
= 0; i
< nmacs
; i
++) {
3808 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3809 scmac_tobe
= maclist
[i
];
3813 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
3814 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3815 const struct ssh_compress
*c
=
3816 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3817 if (in_commasep_string(c
->name
, str
, len
)) {
3822 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
3823 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3824 const struct ssh_compress
*c
=
3825 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3826 if (in_commasep_string(c
->name
, str
, len
)) {
3833 * Work out the number of bits of key we will need from the key
3834 * exchange. We start with the maximum key length of either
3840 csbits
= cscipher_tobe
->keylen
;
3841 scbits
= sccipher_tobe
->keylen
;
3842 nbits
= (csbits
> scbits ? csbits
: scbits
);
3844 /* The keys only have 160-bit entropy, since they're based on
3845 * a SHA-1 hash. So cap the key size at 160 bits. */
3850 * If we're doing Diffie-Hellman group exchange, start by
3851 * requesting a group.
3853 if (kex
== &ssh_diffiehellman_gex
) {
3854 logevent("Doing Diffie-Hellman group exchange");
3855 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3857 * Work out how big a DH group we will need to allow that
3860 pbits
= 512 << ((nbits
- 1) / 64);
3861 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
3862 ssh2_pkt_adduint32(pbits
);
3866 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3867 bombout(("expected key exchange group packet from server"));
3870 p
= ssh2_pkt_getmp();
3871 g
= ssh2_pkt_getmp();
3872 dh_setup_group(p
, g
);
3873 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3874 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3876 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3878 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3879 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3882 logevent("Doing Diffie-Hellman key exchange");
3884 * Now generate and send e for Diffie-Hellman.
3886 e
= dh_create_e(nbits
* 2);
3887 ssh2_pkt_init(kex_init_value
);
3892 if (pktin
.type
!= kex_reply_value
) {
3893 bombout(("expected key exchange reply packet from server"));
3896 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
3897 f
= ssh2_pkt_getmp();
3898 ssh2_pkt_getstring(&sigdata
, &siglen
);
3902 sha_string(&exhash
, hostkeydata
, hostkeylen
);
3903 if (kex
== &ssh_diffiehellman_gex
) {
3904 sha_uint32(&exhash
, pbits
);
3905 sha_mpint(&exhash
, p
);
3906 sha_mpint(&exhash
, g
);
3908 sha_mpint(&exhash
, e
);
3909 sha_mpint(&exhash
, f
);
3910 sha_mpint(&exhash
, K
);
3911 SHA_Final(&exhash
, exchange_hash
);
3916 debug(("Exchange hash is:\n"));
3917 dmemdump(exchange_hash
, 20);
3920 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
3922 !hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
3923 bombout(("Server's host key did not match the signature supplied"));
3928 * Authenticate remote host: verify host key. (We've already
3929 * checked the signature of the exchange hash.)
3931 keystr
= hostkey
->fmtkey(hkey
);
3932 fingerprint
= hostkey
->fingerprint(hkey
);
3933 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
3934 keystr
, fingerprint
);
3935 if (first_kex
) { /* don't bother logging this in rekeys */
3936 logevent("Host key fingerprint is:");
3937 logevent(fingerprint
);
3941 hostkey
->freekey(hkey
);
3944 * Send SSH2_MSG_NEWKEYS.
3946 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
3950 * Expect SSH2_MSG_NEWKEYS from server.
3953 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
3954 bombout(("expected new-keys packet from server"));
3959 * Create and initialise session keys.
3961 cscipher
= cscipher_tobe
;
3962 sccipher
= sccipher_tobe
;
3965 cscomp
= cscomp_tobe
;
3966 sccomp
= sccomp_tobe
;
3967 cscomp
->compress_init();
3968 sccomp
->decompress_init();
3970 * Set IVs after keys. Here we use the exchange hash from the
3971 * _first_ key exchange.
3974 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
3975 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
3976 cscipher
->setcskey(keyspace
);
3977 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
3978 sccipher
->setsckey(keyspace
);
3979 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
3980 cscipher
->setcsiv(keyspace
);
3981 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
3982 sccipher
->setsciv(keyspace
);
3983 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
3984 csmac
->setcskey(keyspace
);
3985 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
3986 scmac
->setsckey(keyspace
);
3989 * If this is the first key exchange phase, we must pass the
3990 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
3991 * wants to see it but because it will need time to initialise
3992 * itself before it sees an actual packet. In subsequent key
3993 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
3994 * it would only confuse the layer above.
4002 * Now we're encrypting. Begin returning 1 to the protocol main
4003 * function so that other things can run on top of the
4004 * transport. If we ever see a KEXINIT, we must go back to the
4007 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
4010 logevent("Server initiated key re-exchange");
4011 goto begin_key_exchange
;
4017 * Add data to an SSH2 channel output buffer.
4019 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4022 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4026 * Attempt to send data on an SSH2 channel.
4028 static int ssh2_try_send(struct ssh_channel
*c
)
4030 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4033 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4034 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4035 len
= c
->v
.v2
.remwindow
;
4036 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4037 len
= c
->v
.v2
.remmaxpkt
;
4038 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4039 ssh2_pkt_adduint32(c
->remoteid
);
4040 ssh2_pkt_addstring_start();
4041 ssh2_pkt_addstring_data(data
, len
);
4043 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4044 c
->v
.v2
.remwindow
-= len
;
4048 * After having sent as much data as we can, return the amount
4051 return bufchain_size(&c
->v
.v2
.outbuffer
);
4055 * Potentially enlarge the window on an SSH2 channel.
4057 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4060 * Never send WINDOW_ADJUST for a channel that the remote side
4061 * already thinks it's closed; there's no point, since it won't
4062 * be sending any more data anyway.
4067 if (newwin
> c
->v
.v2
.locwindow
) {
4068 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4069 ssh2_pkt_adduint32(c
->remoteid
);
4070 ssh2_pkt_adduint32(newwin
- c
->v
.v2
.locwindow
);
4072 c
->v
.v2
.locwindow
= newwin
;
4077 * Handle the SSH2 userauth and connection layers.
4079 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
4082 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4084 AUTH_KEYBOARD_INTERACTIVE
4088 AUTH_TYPE_PUBLICKEY
,
4089 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4090 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4092 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4093 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4095 static int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4096 static int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4097 static int kbd_inter_running
;
4098 static int we_are_in
;
4099 static int num_prompts
, curr_prompt
, echo
;
4100 static char username
[100];
4101 static int got_username
;
4102 static char pwprompt
[200];
4103 static char password
[100];
4104 static void *publickey_blob
;
4105 static int publickey_bloblen
;
4110 * Request userauth protocol, and await a response to it.
4112 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
4113 ssh2_pkt_addstring("ssh-userauth");
4115 crWaitUntilV(ispkt
);
4116 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4117 bombout(("Server refused user authentication protocol"));
4122 * We repeat this whole loop, including the username prompt,
4123 * until we manage a successful authentication. If the user
4124 * types the wrong _password_, they are sent back to the
4125 * beginning to try another username. (If they specify a
4126 * username in the config, they are never asked, even if they
4127 * do give a wrong password.)
4129 * I think this best serves the needs of
4131 * - the people who have no configuration, no keys, and just
4132 * want to try repeated (username,password) pairs until they
4133 * type both correctly
4135 * - people who have keys and configuration but occasionally
4136 * need to fall back to passwords
4138 * - people with a key held in Pageant, who might not have
4139 * logged in to a particular machine before; so they want to
4140 * type a username, and then _either_ their key will be
4141 * accepted, _or_ they will type a password. If they mistype
4142 * the username they will want to be able to get back and
4146 got_username
= FALSE
;
4151 if (got_username
&& !cfg
.change_username
) {
4153 * We got a username last time round this loop, and
4154 * with change_username turned off we don't try to get
4157 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4158 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4159 if (!ssh_get_line("login as: ",
4160 username
, sizeof(username
), FALSE
)) {
4162 * get_line failed to get a username.
4165 logevent("No username provided. Abandoning session.");
4166 ssh_state
= SSH_STATE_CLOSED
;
4171 c_write_str("login as: ");
4173 setup_userpass_input(username
, sizeof(username
), 1);
4175 crWaitUntilV(!ispkt
);
4176 ret
= process_userpass_input(in
, inlen
);
4181 c_write_str("\r\n");
4182 username
[strcspn(username
, "\n\r")] = '\0';
4185 strncpy(username
, cfg
.username
, 99);
4186 username
[99] = '\0';
4187 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4188 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
4192 got_username
= TRUE
;
4195 * Send an authentication request using method "none": (a)
4196 * just in case it succeeds, and (b) so that we know what
4197 * authentication methods we can usefully try next.
4199 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4201 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4202 ssh2_pkt_addstring(username
);
4203 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4204 ssh2_pkt_addstring("none"); /* method */
4206 type
= AUTH_TYPE_NONE
;
4210 tried_pubkey_config
= FALSE
;
4211 tried_agent
= FALSE
;
4212 tried_keyb_inter
= FALSE
;
4213 kbd_inter_running
= FALSE
;
4214 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4217 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4218 keytype
= key_type(cfg
.keyfile
);
4219 if (keytype
== SSH_KEYTYPE_SSH2
)
4220 publickey_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4221 &publickey_bloblen
);
4224 logeventf("Unable to use this key file (%s)",
4225 key_type_to_str(keytype
));
4226 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4227 cfg
.keyfile
, key_type_to_str(keytype
));
4228 c_write_str(msgbuf
);
4229 publickey_blob
= NULL
;
4232 publickey_blob
= NULL
;
4236 * Wait for the result of the last authentication request.
4239 crWaitUntilV(ispkt
);
4240 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4244 * Don't show the banner if we're operating in
4245 * non-verbose non-interactive mode. (It's probably
4246 * a script, which means nobody will read the
4247 * banner _anyway_, and moreover the printing of
4248 * the banner will screw up processing on the
4249 * output of (say) plink.)
4251 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4252 ssh2_pkt_getstring(&banner
, &size
);
4254 c_write_untrusted(banner
, size
);
4256 crWaitUntilV(ispkt
);
4258 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4259 logevent("Access granted");
4264 if (kbd_inter_running
&&
4265 pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4267 * This is either a further set-of-prompts packet
4268 * in keyboard-interactive authentication, or it's
4269 * the same one and we came back here with `gotit'
4270 * set. In the former case, we must reset the
4271 * curr_prompt variable.
4275 } else if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4276 bombout(("Strange packet received during authentication: type %d",
4284 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4285 * we can look at the string in it and know what we can
4286 * helpfully try next.
4288 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4291 ssh2_pkt_getstring(&methods
, &methlen
);
4292 kbd_inter_running
= FALSE
;
4293 if (!ssh2_pkt_getbool()) {
4295 * We have received an unequivocal Access
4296 * Denied. This can translate to a variety of
4299 * - if we'd just tried "none" authentication,
4300 * it's not worth printing anything at all
4302 * - if we'd just tried a public key _offer_,
4303 * the message should be "Server refused our
4304 * key" (or no message at all if the key
4305 * came from Pageant)
4307 * - if we'd just tried anything else, the
4308 * message really should be "Access denied".
4310 * Additionally, if we'd just tried password
4311 * authentication, we should break out of this
4312 * whole loop so as to go back to the username
4315 if (type
== AUTH_TYPE_NONE
) {
4317 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4318 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4319 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4320 c_write_str("Server refused our key\r\n");
4321 logevent("Server refused public key");
4322 } else if (type
== AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4323 /* server declined keyboard-interactive; ignore */
4325 c_write_str("Access denied\r\n");
4326 logevent("Access denied");
4327 if (type
== AUTH_TYPE_PASSWORD
) {
4333 c_write_str("Further authentication required\r\n");
4334 logevent("Further authentication required");
4338 in_commasep_string("publickey", methods
, methlen
);
4340 in_commasep_string("password", methods
, methlen
);
4341 can_keyb_inter
= cfg
.try_ki_auth
&&
4342 in_commasep_string("keyboard-interactive", methods
, methlen
);
4346 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4349 * Most password/passphrase prompts will be
4350 * non-echoing, so we set this to 0 by default.
4351 * Exception is that some keyboard-interactive prompts
4352 * can be echoing, in which case we'll set this to 1.
4356 if (!method
&& can_pubkey
&& agent_exists() && !tried_agent
) {
4358 * Attempt public-key authentication using Pageant.
4360 static unsigned char request
[5], *response
, *p
;
4361 static int responselen
;
4362 static int i
, nkeys
;
4363 static int authed
= FALSE
;
4366 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4367 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4371 logevent("Pageant is running. Requesting keys.");
4373 /* Request the keys held by the agent. */
4374 PUT_32BIT(request
, 1);
4375 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4376 agent_query(request
, 5, &r
, &responselen
);
4377 response
= (unsigned char *) r
;
4378 if (response
&& responselen
>= 5 &&
4379 response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4381 nkeys
= GET_32BIT(p
);
4385 sprintf(buf
, "Pageant has %d SSH2 keys", nkeys
);
4388 for (i
= 0; i
< nkeys
; i
++) {
4389 static char *pkblob
, *alg
, *commentp
;
4390 static int pklen
, alglen
, commentlen
;
4391 static int siglen
, retlen
, len
;
4392 static char *q
, *agentreq
, *ret
;
4397 sprintf(buf
, "Trying Pageant key #%d", i
);
4400 pklen
= GET_32BIT(p
);
4402 if (publickey_blob
&&
4403 pklen
== publickey_bloblen
&&
4404 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
4405 logevent("This key matches configured key file");
4406 tried_pubkey_config
= 1;
4410 alglen
= GET_32BIT(pkblob
);
4412 commentlen
= GET_32BIT(p
);
4416 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4417 ssh2_pkt_addstring(username
);
4418 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4419 ssh2_pkt_addstring("publickey"); /* method */
4420 ssh2_pkt_addbool(FALSE
); /* no signature included */
4421 ssh2_pkt_addstring_start();
4422 ssh2_pkt_addstring_data(alg
, alglen
);
4423 ssh2_pkt_addstring_start();
4424 ssh2_pkt_addstring_data(pkblob
, pklen
);
4427 crWaitUntilV(ispkt
);
4428 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4429 logevent("Key refused");
4433 if (flags
& FLAG_VERBOSE
) {
4435 ("Authenticating with public key \"");
4436 c_write(commentp
, commentlen
);
4437 c_write_str("\" from agent\r\n");
4441 * Server is willing to accept the key.
4442 * Construct a SIGN_REQUEST.
4444 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4445 ssh2_pkt_addstring(username
);
4446 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4447 ssh2_pkt_addstring("publickey"); /* method */
4448 ssh2_pkt_addbool(TRUE
);
4449 ssh2_pkt_addstring_start();
4450 ssh2_pkt_addstring_data(alg
, alglen
);
4451 ssh2_pkt_addstring_start();
4452 ssh2_pkt_addstring_data(pkblob
, pklen
);
4454 siglen
= pktout
.length
- 5 + 4 + 20;
4455 len
= 1; /* message type */
4456 len
+= 4 + pklen
; /* key blob */
4457 len
+= 4 + siglen
; /* data to sign */
4458 len
+= 4; /* flags */
4459 agentreq
= smalloc(4 + len
);
4460 PUT_32BIT(agentreq
, len
);
4462 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4463 PUT_32BIT(q
, pklen
);
4465 memcpy(q
, pkblob
, pklen
);
4467 PUT_32BIT(q
, siglen
);
4469 /* Now the data to be signed... */
4472 memcpy(q
, ssh2_session_id
, 20);
4474 memcpy(q
, pktout
.data
+ 5, pktout
.length
- 5);
4475 q
+= pktout
.length
- 5;
4476 /* And finally the (zero) flags word. */
4478 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
4482 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4483 logevent("Sending Pageant's response");
4484 ssh2_add_sigblob(pkblob
, pklen
,
4485 ret
+ 9, GET_32BIT(ret
+ 5));
4491 ("Pageant failed to answer challenge");
4501 if (!method
&& can_pubkey
&& publickey_blob
4502 && !tried_pubkey_config
) {
4503 unsigned char *pub_blob
;
4504 char *algorithm
, *comment
;
4507 tried_pubkey_config
= TRUE
;
4509 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4510 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4513 * Try the public key supplied in the configuration.
4515 * First, offer the public blob to see if the server is
4516 * willing to accept it.
4518 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4521 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4522 ssh2_pkt_addstring(username
);
4523 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4524 ssh2_pkt_addstring("publickey"); /* method */
4525 ssh2_pkt_addbool(FALSE
); /* no signature included */
4526 ssh2_pkt_addstring(algorithm
);
4527 ssh2_pkt_addstring_start();
4528 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
4530 logevent("Offered public key"); /* FIXME */
4532 crWaitUntilV(ispkt
);
4533 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4535 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4536 continue; /* key refused; give up on it */
4539 logevent("Offer of public key accepted");
4541 * Actually attempt a serious authentication using
4544 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4546 "Passphrase for key \"%.100s\": ",
4552 c_write_str("Authenticating with public key \"");
4553 c_write_str(comment
);
4554 c_write_str("\"\r\n");
4555 method
= AUTH_PUBLICKEY_FILE
;
4559 if (!method
&& can_keyb_inter
&& !tried_keyb_inter
) {
4560 method
= AUTH_KEYBOARD_INTERACTIVE
;
4561 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4562 tried_keyb_inter
= TRUE
;
4564 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4565 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4567 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4568 ssh2_pkt_addstring(username
);
4569 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4570 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4571 ssh2_pkt_addstring(""); /* lang */
4572 ssh2_pkt_addstring("");
4575 crWaitUntilV(ispkt
);
4576 if (pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4577 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4579 logevent("Keyboard-interactive authentication refused");
4580 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4584 kbd_inter_running
= TRUE
;
4588 if (kbd_inter_running
) {
4589 method
= AUTH_KEYBOARD_INTERACTIVE
;
4590 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4591 tried_keyb_inter
= TRUE
;
4593 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4594 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4596 if (curr_prompt
== 0) {
4598 * We've got a fresh USERAUTH_INFO_REQUEST.
4599 * Display header data, and start going through
4602 char *name
, *inst
, *lang
;
4603 int name_len
, inst_len
, lang_len
;
4605 ssh2_pkt_getstring(&name
, &name_len
);
4606 ssh2_pkt_getstring(&inst
, &inst_len
);
4607 ssh2_pkt_getstring(&lang
, &lang_len
);
4609 c_write_untrusted(name
, name_len
);
4610 c_write_str("\r\n");
4613 c_write_untrusted(inst
, inst_len
);
4614 c_write_str("\r\n");
4616 num_prompts
= ssh2_pkt_getuint32();
4620 * If there are prompts remaining in the packet,
4621 * display one and get a response.
4623 if (curr_prompt
< num_prompts
) {
4627 ssh2_pkt_getstring(&prompt
, &prompt_len
);
4628 if (prompt_len
> 0) {
4629 strncpy(pwprompt
, prompt
, sizeof(pwprompt
));
4630 pwprompt
[prompt_len
< sizeof(pwprompt
) ?
4631 prompt_len
: sizeof(pwprompt
)-1] = '\0';
4634 "<server failed to send prompt>: ");
4636 echo
= ssh2_pkt_getbool();
4642 if (!method
&& can_passwd
) {
4643 method
= AUTH_PASSWORD
;
4644 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4645 ssh_pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4646 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
,
4653 if (!ssh_get_line(pwprompt
, password
,
4654 sizeof(password
), TRUE
)) {
4656 * get_line failed to get a password (for
4657 * example because one was supplied on the
4658 * command line which has already failed to
4661 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4662 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4664 ("No more passwords available to try");
4665 ssh2_pkt_addstring("en"); /* language tag */
4667 logevent("Unable to authenticate");
4668 connection_fatal("Unable to authenticate");
4669 ssh_state
= SSH_STATE_CLOSED
;
4674 c_write_untrusted(pwprompt
, strlen(pwprompt
));
4677 setup_userpass_input(password
, sizeof(password
), echo
);
4679 crWaitUntilV(!ispkt
);
4680 ret
= process_userpass_input(in
, inlen
);
4684 c_write_str("\r\n");
4688 if (method
== AUTH_PUBLICKEY_FILE
) {
4690 * We have our passphrase. Now try the actual authentication.
4692 struct ssh2_userkey
*key
;
4694 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
4695 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4696 if (key
== SSH2_WRONG_PASSPHRASE
) {
4697 c_write_str("Wrong passphrase\r\n");
4698 tried_pubkey_config
= FALSE
;
4700 c_write_str("Unable to load private key\r\n");
4701 tried_pubkey_config
= TRUE
;
4703 /* Send a spurious AUTH_NONE to return to the top. */
4704 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4705 ssh2_pkt_addstring(username
);
4706 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4707 ssh2_pkt_addstring("none"); /* method */
4709 type
= AUTH_TYPE_NONE
;
4711 unsigned char *pkblob
, *sigblob
, *sigdata
;
4712 int pkblob_len
, sigblob_len
, sigdata_len
;
4715 * We have loaded the private key and the server
4716 * has announced that it's willing to accept it.
4717 * Hallelujah. Generate a signature and send it.
4719 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4720 ssh2_pkt_addstring(username
);
4721 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4722 ssh2_pkt_addstring("publickey"); /* method */
4723 ssh2_pkt_addbool(TRUE
);
4724 ssh2_pkt_addstring(key
->alg
->name
);
4725 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4726 ssh2_pkt_addstring_start();
4727 ssh2_pkt_addstring_data(pkblob
, pkblob_len
);
4730 * The data to be signed is:
4734 * followed by everything so far placed in the
4737 sigdata_len
= pktout
.length
- 5 + 4 + 20;
4738 sigdata
= smalloc(sigdata_len
);
4739 PUT_32BIT(sigdata
, 20);
4740 memcpy(sigdata
+ 4, ssh2_session_id
, 20);
4741 memcpy(sigdata
+ 24, pktout
.data
+ 5,
4743 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4744 sigdata_len
, &sigblob_len
);
4745 ssh2_add_sigblob(pkblob
, pkblob_len
,
4746 sigblob
, sigblob_len
);
4752 type
= AUTH_TYPE_PUBLICKEY
;
4754 } else if (method
== AUTH_PASSWORD
) {
4756 * We send the password packet lumped tightly together with
4757 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4758 * string long enough to make the total length of the two
4759 * packets constant. This should ensure that a passive
4760 * listener doing traffic analyis can't work out the length
4763 * For this to work, we need an assumption about the
4764 * maximum length of the password packet. I think 256 is
4765 * pretty conservative. Anyone using a password longer than
4766 * that probably doesn't have much to worry about from
4767 * people who find out how long their password is!
4769 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4770 ssh2_pkt_addstring(username
);
4771 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4772 ssh2_pkt_addstring("password");
4773 ssh2_pkt_addbool(FALSE
);
4774 ssh2_pkt_addstring(password
);
4777 * We'll include a string that's an exact multiple of the
4778 * cipher block size. If the cipher is NULL for some
4779 * reason, we don't do this trick at all because we gain
4785 stringlen
= (256 - deferred_len
);
4786 stringlen
+= cscipher
->blksize
- 1;
4787 stringlen
-= (stringlen
% cscipher
->blksize
);
4790 * Temporarily disable actual compression,
4791 * so we can guarantee to get this string
4792 * exactly the length we want it. The
4793 * compression-disabling routine should
4794 * return an integer indicating how many
4795 * bytes we should adjust our string length
4798 stringlen
-= cscomp
->disable_compression();
4800 ssh2_pkt_init(SSH2_MSG_IGNORE
);
4801 ssh2_pkt_addstring_start();
4802 for (i
= 0; i
< stringlen
; i
++) {
4803 char c
= (char) random_byte();
4804 ssh2_pkt_addstring_data(&c
, 1);
4808 ssh_pkt_defersend();
4809 logevent("Sent password");
4810 type
= AUTH_TYPE_PASSWORD
;
4811 } else if (method
== AUTH_KEYBOARD_INTERACTIVE
) {
4812 if (curr_prompt
== 0) {
4813 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4814 ssh2_pkt_adduint32(num_prompts
);
4816 if (need_pw
) { /* only add pw if we just got one! */
4817 ssh2_pkt_addstring(password
);
4818 memset(password
, 0, sizeof(password
));
4821 if (curr_prompt
>= num_prompts
) {
4825 * If there are prompts remaining, we set
4826 * `gotit' so that we won't attempt to get
4827 * another packet. Then we go back round the
4828 * loop and will end up retrieving another
4829 * prompt out of the existing packet. Funky or
4834 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4837 ("No supported authentication methods left to try!\r\n");
4839 ("No supported authentications offered. Disconnecting");
4840 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4841 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4843 ("No supported authentication methods available");
4844 ssh2_pkt_addstring("en"); /* language tag */
4846 ssh_state
= SSH_STATE_CLOSED
;
4850 } while (!we_are_in
);
4853 * Now we're authenticated for the connection protocol. The
4854 * connection protocol will automatically have started at this
4855 * point; there's no need to send SERVICE_REQUEST.
4859 * So now create a channel with a session in it.
4861 ssh_channels
= newtree234(ssh_channelcmp
);
4862 mainchan
= smalloc(sizeof(struct ssh_channel
));
4863 mainchan
->localid
= alloc_channel_id();
4864 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
4865 ssh2_pkt_addstring("session");
4866 ssh2_pkt_adduint32(mainchan
->localid
);
4867 mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
4868 ssh2_pkt_adduint32(mainchan
->v
.v2
.locwindow
); /* our window size */
4869 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
4871 crWaitUntilV(ispkt
);
4872 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
4873 bombout(("Server refused to open a session"));
4875 /* FIXME: error data comes back in FAILURE packet */
4877 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
4878 bombout(("Server's channel confirmation cited wrong channel"));
4881 mainchan
->remoteid
= ssh2_pkt_getuint32();
4882 mainchan
->type
= CHAN_MAINSESSION
;
4883 mainchan
->closes
= 0;
4884 mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
4885 mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
4886 bufchain_init(&mainchan
->v
.v2
.outbuffer
);
4887 add234(ssh_channels
, mainchan
);
4888 logevent("Opened channel for session");
4891 * Potentially enable X11 forwarding.
4893 if (cfg
.x11_forward
) {
4894 char proto
[20], data
[64];
4895 logevent("Requesting X11 forwarding");
4896 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
4897 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
4898 ssh2_pkt_adduint32(mainchan
->remoteid
);
4899 ssh2_pkt_addstring("x11-req");
4900 ssh2_pkt_addbool(1); /* want reply */
4901 ssh2_pkt_addbool(0); /* many connections */
4902 ssh2_pkt_addstring(proto
);
4903 ssh2_pkt_addstring(data
);
4904 ssh2_pkt_adduint32(0); /* screen number */
4908 crWaitUntilV(ispkt
);
4909 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
4910 unsigned i
= ssh2_pkt_getuint32();
4911 struct ssh_channel
*c
;
4912 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
4914 continue; /* nonexistent channel */
4915 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
4917 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4919 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
4920 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
4921 bombout(("Unexpected response to X11 forwarding request:"
4922 " packet type %d", pktin
.type
));
4925 logevent("X11 forwarding refused");
4927 logevent("X11 forwarding enabled");
4928 ssh_X11_fwd_enabled
= TRUE
;
4933 * Enable port forwardings.
4936 static char *e
; /* preserve across crReturn */
4939 int sport
,dport
,sserv
,dserv
;
4940 char sports
[256], dports
[256], host
[256];
4944 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4945 /* Add port forwardings. */
4950 while (*e
&& *e
!= '\t')
4956 while (*e
&& *e
!= ':')
4966 dport
= atoi(dports
);
4970 se
= getservbyname(dports
, NULL
);
4972 dport
= ntohs(se
->s_port
);
4975 "Service lookup failed for destination port \"%s\"",
4980 sport
= atoi(sports
);
4984 se
= getservbyname(sports
, NULL
);
4986 sport
= ntohs(se
->s_port
);
4989 "Service lookup failed for source port \"%s\"",
4994 if (sport
&& dport
) {
4996 pfd_addforward(host
, dport
, sport
);
4997 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
4998 " %s:%.*s%.*s%d%.*s",
4999 sserv ?
strlen(sports
) : 0, sports
,
5000 sserv
, "(", sport
, sserv
, ")",
5002 dserv ?
strlen(dports
) : 0, dports
,
5003 dserv
, "(", dport
, dserv
, ")");
5006 struct ssh_rportfwd
*pf
;
5007 pf
= smalloc(sizeof(*pf
));
5008 strcpy(pf
->dhost
, host
);
5011 if (add234(ssh_rportfwds
, pf
) != pf
) {
5013 "Duplicate remote port forwarding to %s:%d",
5018 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
5019 " forward to %s:%.*s%.*s%d%.*s",
5020 sserv ?
strlen(sports
) : 0, sports
,
5021 sserv
, "(", sport
, sserv
, ")",
5023 dserv ?
strlen(dports
) : 0, dports
,
5024 dserv
, "(", dport
, dserv
, ")");
5026 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
5027 ssh2_pkt_addstring("tcpip-forward");
5028 ssh2_pkt_addbool(1);/* want reply */
5029 if (cfg
.rport_acceptall
)
5030 ssh2_pkt_addstring("0.0.0.0");
5032 ssh2_pkt_addstring("127.0.0.1");
5033 ssh2_pkt_adduint32(sport
);
5037 crWaitUntilV(ispkt
);
5038 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5039 unsigned i
= ssh2_pkt_getuint32();
5040 struct ssh_channel
*c
;
5041 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5043 continue;/* nonexistent channel */
5044 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5046 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5048 if (pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5049 if (pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5050 bombout(("Unexpected response to port "
5051 "forwarding request: packet type %d",
5055 logevent("Server refused this port forwarding");
5057 logevent("Remote port forwarding enabled");
5066 * Potentially enable agent forwarding.
5068 if (cfg
.agentfwd
&& agent_exists()) {
5069 logevent("Requesting OpenSSH-style agent forwarding");
5070 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5071 ssh2_pkt_adduint32(mainchan
->remoteid
);
5072 ssh2_pkt_addstring("auth-agent-req@openssh.com");
5073 ssh2_pkt_addbool(1); /* want reply */
5077 crWaitUntilV(ispkt
);
5078 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5079 unsigned i
= ssh2_pkt_getuint32();
5080 struct ssh_channel
*c
;
5081 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5083 continue; /* nonexistent channel */
5084 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5086 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5088 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5089 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5090 bombout(("Unexpected response to agent forwarding request:"
5091 " packet type %d", pktin
.type
));
5094 logevent("Agent forwarding refused");
5096 logevent("Agent forwarding enabled");
5097 ssh_agentfwd_enabled
= TRUE
;
5102 * Now allocate a pty for the session.
5105 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5106 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5107 ssh2_pkt_addstring("pty-req");
5108 ssh2_pkt_addbool(1); /* want reply */
5109 ssh2_pkt_addstring(cfg
.termtype
);
5110 ssh2_pkt_adduint32(cols
);
5111 ssh2_pkt_adduint32(rows
);
5112 ssh2_pkt_adduint32(0); /* pixel width */
5113 ssh2_pkt_adduint32(0); /* pixel height */
5114 ssh2_pkt_addstring_start();
5115 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
5117 ssh_state
= SSH_STATE_INTERMED
;
5120 crWaitUntilV(ispkt
);
5121 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5122 unsigned i
= ssh2_pkt_getuint32();
5123 struct ssh_channel
*c
;
5124 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5126 continue; /* nonexistent channel */
5127 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5129 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5131 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5132 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5133 bombout(("Unexpected response to pty request:"
5134 " packet type %d", pktin
.type
));
5137 c_write_str("Server refused to allocate pty\r\n");
5138 ssh_editing
= ssh_echoing
= 1;
5140 logevent("Allocated pty");
5143 ssh_editing
= ssh_echoing
= 1;
5147 * Start a shell or a remote command. We may have to attempt
5148 * this twice if the config data has provided a second choice
5155 if (ssh_fallback_cmd
) {
5156 subsys
= cfg
.ssh_subsys2
;
5157 cmd
= cfg
.remote_cmd_ptr2
;
5159 subsys
= cfg
.ssh_subsys
;
5160 cmd
= cfg
.remote_cmd_ptr
;
5163 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5164 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5166 ssh2_pkt_addstring("subsystem");
5167 ssh2_pkt_addbool(1); /* want reply */
5168 ssh2_pkt_addstring(cmd
);
5170 ssh2_pkt_addstring("exec");
5171 ssh2_pkt_addbool(1); /* want reply */
5172 ssh2_pkt_addstring(cmd
);
5174 ssh2_pkt_addstring("shell");
5175 ssh2_pkt_addbool(1); /* want reply */
5179 crWaitUntilV(ispkt
);
5180 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5181 unsigned i
= ssh2_pkt_getuint32();
5182 struct ssh_channel
*c
;
5183 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5185 continue; /* nonexistent channel */
5186 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5188 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5189 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5190 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5191 bombout(("Unexpected response to shell/command request:"
5192 " packet type %d", pktin
.type
));
5196 * We failed to start the command. If this is the
5197 * fallback command, we really are finished; if it's
5198 * not, and if the fallback command exists, try falling
5199 * back to it before complaining.
5201 if (!ssh_fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5202 logevent("Primary command failed; attempting fallback");
5203 ssh_fallback_cmd
= TRUE
;
5206 bombout(("Server refused to start a shell/command"));
5209 logevent("Started a shell/command");
5214 ssh_state
= SSH_STATE_SESSION
;
5218 ssh_special(TS_EOF
);
5223 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
5226 static int try_send
;
5230 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5231 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5234 unsigned i
= ssh2_pkt_getuint32();
5235 struct ssh_channel
*c
;
5236 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5238 continue; /* nonexistent channel */
5239 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5240 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
5241 continue; /* extended but not stderr */
5242 ssh2_pkt_getstring(&data
, &length
);
5245 c
->v
.v2
.locwindow
-= length
;
5247 case CHAN_MAINSESSION
:
5249 from_backend(pktin
.type
==
5250 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5254 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5257 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5260 while (length
> 0) {
5261 if (c
->u
.a
.lensofar
< 4) {
5262 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5263 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5267 c
->u
.a
.lensofar
+= l
;
5269 if (c
->u
.a
.lensofar
== 4) {
5271 4 + GET_32BIT(c
->u
.a
.msglen
);
5272 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5273 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5275 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5277 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5279 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5283 c
->u
.a
.lensofar
+= l
;
5285 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5286 void *reply
, *sentreply
;
5288 agent_query(c
->u
.a
.message
,
5289 c
->u
.a
.totallen
, &reply
,
5294 /* Fake SSH_AGENT_FAILURE. */
5295 sentreply
= "\0\0\0\1\5";
5298 ssh2_add_channel_data(c
, sentreply
,
5303 sfree(c
->u
.a
.message
);
5304 c
->u
.a
.lensofar
= 0;
5311 * If we are not buffering too much data,
5312 * enlarge the window again at the remote side.
5314 if (bufsize
< OUR_V2_WINSIZE
)
5315 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5317 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
5318 ssh_state
= SSH_STATE_CLOSED
;
5319 logevent("Received disconnect message");
5321 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5322 unsigned i
= ssh2_pkt_getuint32();
5323 struct ssh_channel
*c
;
5325 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5327 continue; /* nonexistent channel */
5329 if (c
->type
== CHAN_X11
) {
5331 * Remote EOF on an X11 channel means we should
5332 * wrap up and close the channel ourselves.
5334 x11_close(c
->u
.x11
.s
);
5336 } else if (c
->type
== CHAN_AGENT
) {
5338 } else if (c
->type
== CHAN_SOCKDATA
) {
5339 pfd_close(c
->u
.pfd
.s
);
5342 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5343 unsigned i
= ssh2_pkt_getuint32();
5344 struct ssh_channel
*c
;
5346 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5348 continue; /* nonexistent channel */
5349 /* Do pre-close processing on the channel. */
5351 case CHAN_MAINSESSION
:
5352 break; /* nothing to see here, move along */
5354 if (c
->u
.x11
.s
!= NULL
)
5355 x11_close(c
->u
.x11
.s
);
5362 if (c
->u
.pfd
.s
!= NULL
)
5363 pfd_close(c
->u
.pfd
.s
);
5367 if (c
->closes
== 0) {
5368 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5369 ssh2_pkt_adduint32(c
->remoteid
);
5372 del234(ssh_channels
, c
);
5373 bufchain_clear(&c
->v
.v2
.outbuffer
);
5377 * See if that was the last channel left open.
5379 if (count234(ssh_channels
) == 0) {
5382 * We used to send SSH_MSG_DISCONNECT here,
5383 * because I'd believed that _every_ conforming
5384 * SSH2 connection had to end with a disconnect
5385 * being sent by at least one side; apparently
5386 * I was wrong and it's perfectly OK to
5387 * unceremoniously slam the connection shut
5388 * when you're done, and indeed OpenSSH feels
5389 * this is more polite than sending a
5390 * DISCONNECT. So now we don't.
5392 logevent("All channels closed. Disconnecting");
5393 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5394 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5395 ssh2_pkt_addstring("All open channels closed");
5396 ssh2_pkt_addstring("en"); /* language tag */
5399 ssh_state
= SSH_STATE_CLOSED
;
5402 continue; /* remote sends close; ignore (FIXME) */
5403 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5404 unsigned i
= ssh2_pkt_getuint32();
5405 struct ssh_channel
*c
;
5406 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5408 continue; /* nonexistent channel */
5409 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5411 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
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 confirming this */
5419 c
->remoteid
= ssh2_pkt_getuint32();
5420 c
->type
= CHAN_SOCKDATA
;
5421 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
5422 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
5424 pfd_confirm(c
->u
.pfd
.s
);
5427 * We have a pending close on this channel,
5428 * which we decided on before the server acked
5429 * the channel open. So now we know the
5430 * remoteid, we can close it again.
5432 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5433 ssh2_pkt_adduint32(c
->remoteid
);
5436 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5437 unsigned i
= ssh2_pkt_getuint32();
5438 struct ssh_channel
*c
;
5439 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5441 continue; /* nonexistent channel */
5442 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5443 continue; /* dunno why they're failing this */
5445 logevent("Forwarded connection refused by server");
5447 pfd_close(c
->u
.pfd
.s
);
5449 del234(ssh_channels
, c
);
5451 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5454 int typelen
, want_reply
;
5455 struct ssh_channel
*c
;
5457 localid
= ssh2_pkt_getuint32();
5458 ssh2_pkt_getstring(&type
, &typelen
);
5459 want_reply
= ssh2_pkt_getbool();
5462 * First, check that the channel exists. Otherwise,
5463 * we can instantly disconnect with a rude message.
5465 c
= find234(ssh_channels
, &localid
, ssh_channelfind
);
5468 sprintf(buf
, "Received channel request for nonexistent"
5469 " channel %d", localid
);
5471 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5472 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5473 ssh2_pkt_addstring(buf
);
5474 ssh2_pkt_addstring("en"); /* language tag */
5476 connection_fatal("%s", buf
);
5477 ssh_state
= SSH_STATE_CLOSED
;
5482 * Having got the channel number, we now look at
5483 * the request type string to see if it's something
5486 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5488 /* We recognise "exit-status" on the primary channel. */
5490 ssh_exitcode
= ssh2_pkt_getuint32();
5491 sprintf(buf
, "Server sent command exit status %d",
5495 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS
);
5496 ssh2_pkt_adduint32(c
->remoteid
);
5501 * This is a channel request we don't know
5502 * about, so we now either ignore the request
5503 * or respond with CHANNEL_FAILURE, depending
5507 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE
);
5508 ssh2_pkt_adduint32(c
->remoteid
);
5512 } else if (pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5514 int typelen
, want_reply
;
5516 ssh2_pkt_getstring(&type
, &typelen
);
5517 want_reply
= ssh2_pkt_getbool();
5520 * We currently don't support any global requests
5521 * at all, so we either ignore the request or
5522 * respond with REQUEST_FAILURE, depending on
5526 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5529 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5533 struct ssh_channel
*c
;
5534 unsigned remid
, winsize
, pktsize
;
5535 ssh2_pkt_getstring(&type
, &typelen
);
5536 c
= smalloc(sizeof(struct ssh_channel
));
5538 remid
= ssh2_pkt_getuint32();
5539 winsize
= ssh2_pkt_getuint32();
5540 pktsize
= ssh2_pkt_getuint32();
5542 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5543 if (!ssh_X11_fwd_enabled
)
5544 error
= "X11 forwarding is not enabled";
5545 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5547 error
= "Unable to open an X11 connection";
5551 } else if (typelen
== 15 &&
5552 !memcmp(type
, "forwarded-tcpip", 15)) {
5553 struct ssh_rportfwd pf
, *realpf
;
5556 ssh2_pkt_getstring(&dummy
, &dummylen
);/* skip address */
5557 pf
.sport
= ssh2_pkt_getuint32();
5558 realpf
= find234(ssh_rportfwds
, &pf
, NULL
);
5559 if (realpf
== NULL
) {
5560 error
= "Remote port is not recognised";
5562 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5565 sprintf(buf
, "Received remote port open request for %s:%d",
5566 realpf
->dhost
, realpf
->dport
);
5569 sprintf(buf
, "Port open failed: %s", e
);
5571 error
= "Port open failed";
5573 logevent("Forwarded port opened successfully");
5574 c
->type
= CHAN_SOCKDATA
;
5577 } else if (typelen
== 22 &&
5578 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5579 if (!ssh_agentfwd_enabled
)
5580 error
= "Agent forwarding is not enabled";
5582 c
->type
= CHAN_AGENT
; /* identify channel type */
5583 c
->u
.a
.lensofar
= 0;
5586 error
= "Unsupported channel type requested";
5589 c
->remoteid
= remid
;
5591 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5592 ssh2_pkt_adduint32(c
->remoteid
);
5593 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
5594 ssh2_pkt_addstring(error
);
5595 ssh2_pkt_addstring("en"); /* language tag */
5599 c
->localid
= alloc_channel_id();
5601 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5602 c
->v
.v2
.remwindow
= winsize
;
5603 c
->v
.v2
.remmaxpkt
= pktsize
;
5604 bufchain_init(&c
->v
.v2
.outbuffer
);
5605 add234(ssh_channels
, c
);
5606 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5607 ssh2_pkt_adduint32(c
->remoteid
);
5608 ssh2_pkt_adduint32(c
->localid
);
5609 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);
5610 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5614 bombout(("Strange packet received: type %d", pktin
.type
));
5619 * We have spare data. Add it to the channel buffer.
5621 ssh2_add_channel_data(mainchan
, in
, inlen
);
5626 struct ssh_channel
*c
;
5628 * Try to send data on all channels if we can.
5630 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
5631 int bufsize
= ssh2_try_send(c
);
5634 case CHAN_MAINSESSION
:
5635 /* stdin need not receive an unthrottle
5636 * notification since it will be polled */
5639 x11_unthrottle(c
->u
.x11
.s
);
5642 /* agent sockets are request/response and need no
5643 * buffer management */
5646 pfd_unthrottle(c
->u
.pfd
.s
);
5658 * Handle the top-level SSH2 protocol.
5660 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
5662 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
5664 do_ssh2_authconn(in
, inlen
, ispkt
);
5668 * Called to set up the connection.
5670 * Returns an error message, or NULL on success.
5672 static char *ssh_init(char *host
, int port
, char **realhost
, int nodelay
)
5677 if (crypto_startup() == 0)
5678 return "Microsoft high encryption pack not installed!";
5684 ssh1_throttle_count
= 0;
5685 ssh_overall_bufsize
= 0;
5686 ssh_fallback_cmd
= 0;
5688 p
= connect_to_host(host
, port
, realhost
, nodelay
);
5696 * Called to send data down the Telnet connection.
5698 static int ssh_send(char *buf
, int len
)
5700 if (s
== NULL
|| ssh_protocol
== NULL
)
5703 ssh_protocol(buf
, len
, 0);
5705 return ssh_sendbuffer();
5709 * Called to query the current amount of buffered stdin data.
5711 static int ssh_sendbuffer(void)
5715 if (s
== NULL
|| ssh_protocol
== NULL
)
5719 * If the SSH socket itself has backed up, add the total backup
5720 * size on that to any individual buffer on the stdin channel.
5723 if (ssh_throttled_all
)
5724 override_value
= ssh_overall_bufsize
;
5726 if (ssh_version
== 1) {
5727 return override_value
;
5728 } else if (ssh_version
== 2) {
5729 if (!mainchan
|| mainchan
->closes
> 0)
5730 return override_value
;
5732 return override_value
+ bufchain_size(&mainchan
->v
.v2
.outbuffer
);
5739 * Called to set the size of the window from SSH's POV.
5741 static void ssh_size(void)
5743 switch (ssh_state
) {
5744 case SSH_STATE_BEFORE_SIZE
:
5745 case SSH_STATE_PREPACKET
:
5746 case SSH_STATE_CLOSED
:
5747 break; /* do nothing */
5748 case SSH_STATE_INTERMED
:
5749 size_needed
= TRUE
; /* buffer for later */
5751 case SSH_STATE_SESSION
:
5753 if (ssh_version
== 1) {
5754 send_packet(SSH1_CMSG_WINDOW_SIZE
,
5755 PKT_INT
, rows
, PKT_INT
, cols
,
5756 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5758 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5759 ssh2_pkt_adduint32(mainchan
->remoteid
);
5760 ssh2_pkt_addstring("window-change");
5761 ssh2_pkt_addbool(0);
5762 ssh2_pkt_adduint32(cols
);
5763 ssh2_pkt_adduint32(rows
);
5764 ssh2_pkt_adduint32(0);
5765 ssh2_pkt_adduint32(0);
5774 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5775 * can send an EOF and collect resulting output (e.g. `plink
5778 static void ssh_special(Telnet_Special code
)
5780 if (code
== TS_EOF
) {
5781 if (ssh_state
!= SSH_STATE_SESSION
) {
5783 * Buffer the EOF in case we are pre-SESSION, so we can
5784 * send it as soon as we reach SESSION.
5790 if (ssh_version
== 1) {
5791 send_packet(SSH1_CMSG_EOF
, PKT_END
);
5793 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
5794 ssh2_pkt_adduint32(mainchan
->remoteid
);
5797 logevent("Sent EOF message");
5798 } else if (code
== TS_PING
) {
5799 if (ssh_state
== SSH_STATE_CLOSED
5800 || ssh_state
== SSH_STATE_PREPACKET
) return;
5801 if (ssh_version
== 1) {
5802 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
5803 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
5805 ssh2_pkt_init(SSH2_MSG_IGNORE
);
5806 ssh2_pkt_addstring_start();
5814 void *new_sock_channel(Socket s
)
5816 struct ssh_channel
*c
;
5817 c
= smalloc(sizeof(struct ssh_channel
));
5820 c
->remoteid
= -1; /* to be set when open confirmed */
5821 c
->localid
= alloc_channel_id();
5823 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
5825 bufchain_init(&c
->v
.v2
.outbuffer
);
5826 add234(ssh_channels
, c
);
5832 * This is called when stdout/stderr (the entity to which
5833 * from_backend sends data) manages to clear some backlog.
5835 void ssh_unthrottle(int bufsize
)
5837 if (ssh_version
== 1) {
5838 if (ssh1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
5839 ssh1_stdout_throttling
= 0;
5843 if (mainchan
&& mainchan
->closes
== 0)
5844 ssh2_set_window(mainchan
, OUR_V2_WINSIZE
- bufsize
);
5848 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
5850 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
5853 sprintf(buf
, "Opening forwarded connection to %.512s:%d", hostname
, port
);
5856 if (ssh_version
== 1) {
5857 send_packet(SSH1_MSG_PORT_OPEN
,
5858 PKT_INT
, c
->localid
,
5861 //PKT_STR, <org:orgport>,
5864 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
5865 ssh2_pkt_addstring("direct-tcpip");
5866 ssh2_pkt_adduint32(c
->localid
);
5867 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5868 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);/* our window size */
5869 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5870 ssh2_pkt_addstring(hostname
);
5871 ssh2_pkt_adduint32(port
);
5873 * We make up values for the originator data; partly it's
5874 * too much hassle to keep track, and partly I'm not
5875 * convinced the server should be told details like that
5876 * about my local network configuration.
5878 ssh2_pkt_addstring("client-side-connection");
5879 ssh2_pkt_adduint32(0);
5885 static Socket
ssh_socket(void)
5890 static int ssh_sendok(void)
5895 static int ssh_ldisc(int option
)
5897 if (option
== LD_ECHO
)
5899 if (option
== LD_EDIT
)
5904 static int ssh_return_exitcode(void)
5906 return ssh_exitcode
;
5909 Backend ssh_backend
= {
5916 ssh_return_exitcode
,