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
186 #define BUG_SSH2_DH_GEX 64
188 static int ssh_pkt_ctx
= 0;
190 #define translate(x) if (type == x) return #x
191 #define translatec(x,ctx) if (type == x && (ssh_pkt_ctx & ctx)) return #x
192 char *ssh1_pkt_type(int type
)
194 translate(SSH1_MSG_DISCONNECT
);
195 translate(SSH1_SMSG_PUBLIC_KEY
);
196 translate(SSH1_CMSG_SESSION_KEY
);
197 translate(SSH1_CMSG_USER
);
198 translate(SSH1_CMSG_AUTH_RSA
);
199 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
200 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
201 translate(SSH1_CMSG_AUTH_PASSWORD
);
202 translate(SSH1_CMSG_REQUEST_PTY
);
203 translate(SSH1_CMSG_WINDOW_SIZE
);
204 translate(SSH1_CMSG_EXEC_SHELL
);
205 translate(SSH1_CMSG_EXEC_CMD
);
206 translate(SSH1_SMSG_SUCCESS
);
207 translate(SSH1_SMSG_FAILURE
);
208 translate(SSH1_CMSG_STDIN_DATA
);
209 translate(SSH1_SMSG_STDOUT_DATA
);
210 translate(SSH1_SMSG_STDERR_DATA
);
211 translate(SSH1_CMSG_EOF
);
212 translate(SSH1_SMSG_EXIT_STATUS
);
213 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
214 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
215 translate(SSH1_MSG_CHANNEL_DATA
);
216 translate(SSH1_MSG_CHANNEL_CLOSE
);
217 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
218 translate(SSH1_SMSG_X11_OPEN
);
219 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
220 translate(SSH1_MSG_PORT_OPEN
);
221 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
222 translate(SSH1_SMSG_AGENT_OPEN
);
223 translate(SSH1_MSG_IGNORE
);
224 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
225 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
226 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
227 translate(SSH1_MSG_DEBUG
);
228 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
229 translate(SSH1_CMSG_AUTH_TIS
);
230 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
231 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
232 translate(SSH1_CMSG_AUTH_CCARD
);
233 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
234 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
237 char *ssh2_pkt_type(int type
)
239 translate(SSH2_MSG_DISCONNECT
);
240 translate(SSH2_MSG_IGNORE
);
241 translate(SSH2_MSG_UNIMPLEMENTED
);
242 translate(SSH2_MSG_DEBUG
);
243 translate(SSH2_MSG_SERVICE_REQUEST
);
244 translate(SSH2_MSG_SERVICE_ACCEPT
);
245 translate(SSH2_MSG_KEXINIT
);
246 translate(SSH2_MSG_NEWKEYS
);
247 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
248 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
249 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
250 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
251 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
252 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
253 translate(SSH2_MSG_USERAUTH_REQUEST
);
254 translate(SSH2_MSG_USERAUTH_FAILURE
);
255 translate(SSH2_MSG_USERAUTH_SUCCESS
);
256 translate(SSH2_MSG_USERAUTH_BANNER
);
257 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
258 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
259 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
260 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
261 translate(SSH2_MSG_GLOBAL_REQUEST
);
262 translate(SSH2_MSG_REQUEST_SUCCESS
);
263 translate(SSH2_MSG_REQUEST_FAILURE
);
264 translate(SSH2_MSG_CHANNEL_OPEN
);
265 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
266 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
267 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
268 translate(SSH2_MSG_CHANNEL_DATA
);
269 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
270 translate(SSH2_MSG_CHANNEL_EOF
);
271 translate(SSH2_MSG_CHANNEL_CLOSE
);
272 translate(SSH2_MSG_CHANNEL_REQUEST
);
273 translate(SSH2_MSG_CHANNEL_SUCCESS
);
274 translate(SSH2_MSG_CHANNEL_FAILURE
);
280 #define GET_32BIT(cp) \
281 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
282 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
283 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
284 ((unsigned long)(unsigned char)(cp)[3]))
286 #define PUT_32BIT(cp, value) { \
287 (cp)[0] = (unsigned char)((value) >> 24); \
288 (cp)[1] = (unsigned char)((value) >> 16); \
289 (cp)[2] = (unsigned char)((value) >> 8); \
290 (cp)[3] = (unsigned char)(value); }
292 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
294 /* Coroutine mechanics for the sillier bits of the code */
295 #define crBegin1 static int crLine = 0;
296 #define crBegin2 switch(crLine) { case 0:;
297 #define crBegin crBegin1; crBegin2;
298 #define crFinish(z) } crLine = 0; return (z)
299 #define crFinishV } crLine = 0; return
300 #define crReturn(z) \
302 crLine=__LINE__; return (z); case __LINE__:;\
306 crLine=__LINE__; return; case __LINE__:;\
308 #define crStop(z) do{ crLine = 0; return (z); }while(0)
309 #define crStopV do{ crLine = 0; return; }while(0)
310 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
311 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
313 extern char *x11_init(Socket
*, char *, void *);
314 extern void x11_close(Socket
);
315 extern int x11_send(Socket
, char *, int);
316 extern void x11_invent_auth(char *, int, char *, int);
317 extern void x11_unthrottle(Socket s
);
318 extern void x11_override_throttle(Socket s
, int enable
);
320 extern char *pfd_newconnect(Socket
* s
, char *hostname
, int port
, void *c
);
321 extern char *pfd_addforward(char *desthost
, int destport
, int port
);
322 extern void pfd_close(Socket s
);
323 extern int pfd_send(Socket s
, char *data
, int len
);
324 extern void pfd_confirm(Socket s
);
325 extern void pfd_unthrottle(Socket s
);
326 extern void pfd_override_throttle(Socket s
, int enable
);
328 static void ssh2_pkt_init(int pkt_type
);
329 static void ssh2_pkt_addbool(unsigned char value
);
330 static void ssh2_pkt_adduint32(unsigned long value
);
331 static void ssh2_pkt_addstring_start(void);
332 static void ssh2_pkt_addstring_str(char *data
);
333 static void ssh2_pkt_addstring_data(char *data
, int len
);
334 static void ssh2_pkt_addstring(char *data
);
335 static char *ssh2_mpint_fmt(Bignum b
, int *len
);
336 static void ssh2_pkt_addmp(Bignum b
);
337 static int ssh2_pkt_construct(void);
338 static void ssh2_pkt_send(void);
341 * Buffer management constants. There are several of these for
342 * various different purposes:
344 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
345 * on a local data stream before we throttle the whole SSH
346 * connection (in SSH1 only). Throttling the whole connection is
347 * pretty drastic so we set this high in the hope it won't
350 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
351 * on the SSH connection itself before we defensively throttle
352 * _all_ local data streams. This is pretty drastic too (though
353 * thankfully unlikely in SSH2 since the window mechanism should
354 * ensure that the server never has any need to throttle its end
355 * of the connection), so we set this high as well.
357 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
361 #define SSH1_BUFFER_LIMIT 32768
362 #define SSH_MAX_BACKLOG 32768
363 #define OUR_V2_WINSIZE 16384
365 const static struct ssh_kex
*kex_algs
[] = {
366 &ssh_diffiehellman_gex
,
370 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
372 static void nullmac_key(unsigned char *key
)
375 static void nullmac_generate(unsigned char *blk
, int len
,
379 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
)
383 const static struct ssh_mac ssh_mac_none
= {
384 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
386 const static struct ssh_mac
*macs
[] = {
387 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
389 const static struct ssh_mac
*buggymacs
[] = {
390 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
393 static void ssh_comp_none_init(void)
396 static int ssh_comp_none_block(unsigned char *block
, int len
,
397 unsigned char **outblock
, int *outlen
)
401 static int ssh_comp_none_disable(void)
405 const static struct ssh_compress ssh_comp_none
= {
407 ssh_comp_none_init
, ssh_comp_none_block
,
408 ssh_comp_none_init
, ssh_comp_none_block
,
409 ssh_comp_none_disable
411 extern const struct ssh_compress ssh_zlib
;
412 const static struct ssh_compress
*compressions
[] = {
413 &ssh_zlib
, &ssh_comp_none
416 enum { /* channel types */
421 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
425 * 2-3-4 tree storing channels.
428 unsigned remoteid
, localid
;
431 * In SSH1, this value contains four bits:
433 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
434 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
435 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
436 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
438 * A channel is completely finished with when all four bits are set.
442 struct ssh1_data_channel
{
445 struct ssh2_data_channel
{
447 unsigned remwindow
, remmaxpkt
;
452 struct ssh_agent_channel
{
453 unsigned char *message
;
454 unsigned char msglen
[4];
455 int lensofar
, totallen
;
457 struct ssh_x11_channel
{
460 struct ssh_pfd_channel
{
467 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
468 * 2 use this structure in different ways, reflecting SSH 2's
469 * altogether saner approach to port forwarding.
471 * In SSH 1, you arrange a remote forwarding by sending the server
472 * the remote port number, and the local destination host:port.
473 * When a connection comes in, the server sends you back that
474 * host:port pair, and you connect to it. This is a ready-made
475 * security hole if you're not on the ball: a malicious server
476 * could send you back _any_ host:port pair, so if you trustingly
477 * connect to the address it gives you then you've just opened the
478 * entire inside of your corporate network just by connecting
479 * through it to a dodgy SSH server. Hence, we must store a list of
480 * host:port pairs we _are_ trying to forward to, and reject a
481 * connection request from the server if it's not in the list.
483 * In SSH 2, each side of the connection minds its own business and
484 * doesn't send unnecessary information to the other. You arrange a
485 * remote forwarding by sending the server just the remote port
486 * number. When a connection comes in, the server tells you which
487 * of its ports was connected to; and _you_ have to remember what
488 * local host:port pair went with that port number.
490 * Hence: in SSH 1 this structure stores host:port pairs we intend
491 * to allow connections to, and is indexed by those host:port
492 * pairs. In SSH 2 it stores a mapping from source port to
493 * destination host:port pair, and is indexed by source port.
495 struct ssh_rportfwd
{
496 unsigned sport
, dport
;
509 static SHA_State exhash
, exhashbase
;
511 static Socket s
= NULL
;
513 static unsigned char session_key
[32];
514 static int ssh1_compressing
;
515 static int ssh1_remote_protoflags
;
516 static int ssh1_local_protoflags
;
517 static int ssh_agentfwd_enabled
;
518 static int ssh_X11_fwd_enabled
;
519 static int ssh_remote_bugs
;
520 static const struct ssh_cipher
*cipher
= NULL
;
521 static const struct ssh2_cipher
*cscipher
= NULL
;
522 static const struct ssh2_cipher
*sccipher
= NULL
;
523 static const struct ssh_mac
*csmac
= NULL
;
524 static const struct ssh_mac
*scmac
= NULL
;
525 static const struct ssh_compress
*cscomp
= NULL
;
526 static const struct ssh_compress
*sccomp
= NULL
;
527 static const struct ssh_kex
*kex
= NULL
;
528 static const struct ssh_signkey
*hostkey
= NULL
;
529 static unsigned char ssh2_session_id
[20];
531 static char *savedhost
;
532 static int savedport
;
533 static int ssh_send_ok
;
534 static int ssh_echoing
, ssh_editing
;
536 static tree234
*ssh_channels
; /* indexed by local id */
537 static struct ssh_channel
*mainchan
; /* primary session channel */
538 static int ssh_exitcode
= -1;
540 static tree234
*ssh_rportfwds
;
544 SSH_STATE_BEFORE_SIZE
,
548 } ssh_state
= SSH_STATE_PREPACKET
;
550 static int size_needed
= FALSE
, eof_needed
= FALSE
;
552 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
553 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
554 static unsigned char *deferred_send_data
= NULL
;
555 static int deferred_len
= 0, deferred_size
= 0;
558 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
559 * that fails. This variable is the means by which scp.c can reach
560 * into the SSH code and find out which one it got.
562 int ssh_fallback_cmd
= 0;
564 static int ssh_version
;
565 static int ssh1_throttle_count
;
566 static int ssh_overall_bufsize
;
567 static int ssh_throttled_all
;
568 static int ssh1_stdout_throttling
;
569 static void (*ssh_protocol
) (unsigned char *in
, int inlen
, int ispkt
);
570 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
571 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
572 static void ssh_size(void);
573 static void ssh_special(Telnet_Special
);
574 static int ssh2_try_send(struct ssh_channel
*c
);
575 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
577 static void ssh_throttle_all(int enable
, int bufsize
);
578 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
579 static int (*s_rdpkt
) (unsigned char **data
, int *datalen
);
580 static int ssh_sendbuffer(void);
582 static struct rdpkt1_state_tag
{
583 long len
, pad
, biglen
, to_read
;
584 unsigned long realcrc
, gotcrc
;
590 static struct rdpkt2_state_tag
{
591 long len
, pad
, payload
, packetlen
, maclen
;
594 unsigned long incoming_sequence
;
597 static int ssh_channelcmp(void *av
, void *bv
)
599 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
600 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
601 if (a
->localid
< b
->localid
)
603 if (a
->localid
> b
->localid
)
607 static int ssh_channelfind(void *av
, void *bv
)
609 unsigned *a
= (unsigned *) av
;
610 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
618 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
620 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
621 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
623 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
624 return i
< 0 ?
-1 : +1;
625 if (a
->dport
> b
->dport
)
627 if (a
->dport
< b
->dport
)
632 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
634 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
635 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
637 if (a
->sport
> b
->sport
)
639 if (a
->sport
< b
->sport
)
644 static int alloc_channel_id(void)
646 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
647 unsigned low
, high
, mid
;
649 struct ssh_channel
*c
;
652 * First-fit allocation of channel numbers: always pick the
653 * lowest unused one. To do this, binary-search using the
654 * counted B-tree to find the largest channel ID which is in a
655 * contiguous sequence from the beginning. (Precisely
656 * everything in that sequence must have ID equal to its tree
657 * index plus CHANNEL_NUMBER_OFFSET.)
659 tsize
= count234(ssh_channels
);
663 while (high
- low
> 1) {
664 mid
= (high
+ low
) / 2;
665 c
= index234(ssh_channels
, mid
);
666 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
667 low
= mid
; /* this one is fine */
669 high
= mid
; /* this one is past it */
672 * Now low points to either -1, or the tree index of the
673 * largest ID in the initial sequence.
676 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
677 assert(NULL
== find234(ssh_channels
, &i
, ssh_channelfind
));
679 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
682 static void c_write(char *buf
, int len
)
684 if ((flags
& FLAG_STDERR
)) {
686 for (i
= 0; i
< len
; i
++)
688 fputc(buf
[i
], stderr
);
691 from_backend(1, buf
, len
);
694 static void c_write_untrusted(char *buf
, int len
)
697 for (i
= 0; i
< len
; i
++) {
700 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
705 static void c_write_str(char *buf
)
707 c_write(buf
, strlen(buf
));
711 * Collect incoming data in the incoming packet buffer.
712 * Decipher and verify the packet when it is completely read.
713 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
714 * Update the *data and *datalen variables.
715 * Return the additional nr of bytes needed, or 0 when
716 * a complete packet is available.
718 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
720 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
729 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
730 while ((*datalen
) == 0)
732 st
->len
= (st
->len
<< 8) + **data
;
733 (*data
)++, (*datalen
)--;
736 st
->pad
= 8 - (st
->len
% 8);
737 st
->biglen
= st
->len
+ st
->pad
;
738 pktin
.length
= st
->len
- 5;
740 if (pktin
.maxlen
< st
->biglen
) {
741 pktin
.maxlen
= st
->biglen
;
742 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+ APIEXTRA
) :
743 srealloc(pktin
.data
, st
->biglen
+ APIEXTRA
));
745 fatalbox("Out of memory");
748 st
->to_read
= st
->biglen
;
750 while (st
->to_read
> 0) {
751 st
->chunk
= st
->to_read
;
752 while ((*datalen
) == 0)
753 crReturn(st
->to_read
);
754 if (st
->chunk
> (*datalen
))
755 st
->chunk
= (*datalen
);
756 memcpy(st
->p
, *data
, st
->chunk
);
758 *datalen
-= st
->chunk
;
760 st
->to_read
-= st
->chunk
;
763 if (cipher
&& detect_attack(pktin
.data
, st
->biglen
, NULL
)) {
764 bombout(("Network attack (CRC compensation) detected!"));
769 cipher
->decrypt(pktin
.data
, st
->biglen
);
771 st
->realcrc
= crc32(pktin
.data
, st
->biglen
- 4);
772 st
->gotcrc
= GET_32BIT(pktin
.data
+ st
->biglen
- 4);
773 if (st
->gotcrc
!= st
->realcrc
) {
774 bombout(("Incorrect CRC received on packet"));
778 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
780 if (ssh1_compressing
) {
781 unsigned char *decompblk
;
783 zlib_decompress_block(pktin
.body
- 1, pktin
.length
+ 1,
784 &decompblk
, &decomplen
);
786 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
787 pktin
.maxlen
= st
->pad
+ decomplen
;
788 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+ APIEXTRA
);
789 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
791 fatalbox("Out of memory");
794 memcpy(pktin
.body
- 1, decompblk
, decomplen
);
796 pktin
.length
= decomplen
- 1;
799 pktin
.type
= pktin
.body
[-1];
801 log_packet(PKT_INCOMING
, pktin
.type
, ssh1_pkt_type(pktin
.type
),
802 pktin
.body
, pktin
.length
);
804 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
805 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
806 pktin
.type
== SSH1_MSG_DEBUG
||
807 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
808 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
809 long stringlen
= GET_32BIT(pktin
.body
);
810 if (stringlen
+ 4 != pktin
.length
) {
811 bombout(("Received data packet with bogus string length"));
816 if (pktin
.type
== SSH1_MSG_DEBUG
) {
817 /* log debug message */
819 int stringlen
= GET_32BIT(pktin
.body
);
820 strcpy(buf
, "Remote debug message: ");
823 memcpy(buf
+ 8, pktin
.body
+ 4, stringlen
);
824 buf
[8 + stringlen
] = '\0';
827 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
832 if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
833 /* log reason code in disconnect message */
835 unsigned msglen
= GET_32BIT(pktin
.body
);
837 strcpy(buf
, "Remote sent disconnect: ");
838 nowlen
= strlen(buf
);
839 if (msglen
> sizeof(buf
) - nowlen
- 1)
840 msglen
= sizeof(buf
) - nowlen
- 1;
841 memcpy(buf
+ nowlen
, pktin
.body
+ 4, msglen
);
842 buf
[nowlen
+ msglen
] = '\0';
843 /* logevent(buf); (this is now done within the bombout macro) */
844 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
851 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
853 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
861 st
->cipherblk
= sccipher
->blksize
;
864 if (st
->cipherblk
< 8)
867 if (pktin
.maxlen
< st
->cipherblk
) {
868 pktin
.maxlen
= st
->cipherblk
;
871 NULL ?
smalloc(st
->cipherblk
+
872 APIEXTRA
) : srealloc(pktin
.data
,
876 fatalbox("Out of memory");
880 * Acquire and decrypt the first block of the packet. This will
881 * contain the length and padding details.
883 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
884 while ((*datalen
) == 0)
885 crReturn(st
->cipherblk
- st
->i
);
886 pktin
.data
[st
->i
] = *(*data
)++;
891 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
894 * Now get the length and padding figures.
896 st
->len
= GET_32BIT(pktin
.data
);
897 st
->pad
= pktin
.data
[4];
900 * _Completely_ silly lengths should be stomped on before they
901 * do us any more damage.
903 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
904 bombout(("Incoming packet was garbled on decryption"));
909 * This enables us to deduce the payload length.
911 st
->payload
= st
->len
- st
->pad
- 1;
913 pktin
.length
= st
->payload
+ 5;
916 * So now we can work out the total packet length.
918 st
->packetlen
= st
->len
+ 4;
919 st
->maclen
= scmac ? scmac
->len
: 0;
922 * Adjust memory allocation if packet is too big.
924 if (pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
925 pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
928 NULL ?
smalloc(pktin
.maxlen
+ APIEXTRA
) : srealloc(pktin
.data
,
933 fatalbox("Out of memory");
937 * Read and decrypt the remainder of the packet.
939 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
941 while ((*datalen
) == 0)
942 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
943 pktin
.data
[st
->i
] = *(*data
)++;
946 /* Decrypt everything _except_ the MAC. */
948 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
949 st
->packetlen
- st
->cipherblk
);
955 && !scmac
->verify(pktin
.data
, st
->len
+ 4,
956 st
->incoming_sequence
)) {
957 bombout(("Incorrect MAC received on packet"));
960 st
->incoming_sequence
++; /* whether or not we MACed */
963 * Decompress packet payload.
966 unsigned char *newpayload
;
968 if (sccomp
&& sccomp
->decompress(pktin
.data
+ 5, pktin
.length
- 5,
969 &newpayload
, &newlen
)) {
970 if (pktin
.maxlen
< newlen
+ 5) {
971 pktin
.maxlen
= newlen
+ 5;
974 NULL ?
smalloc(pktin
.maxlen
+
975 APIEXTRA
) : srealloc(pktin
.data
,
979 fatalbox("Out of memory");
981 pktin
.length
= 5 + newlen
;
982 memcpy(pktin
.data
+ 5, newpayload
, newlen
);
988 pktin
.type
= pktin
.data
[5];
990 log_packet(PKT_INCOMING
, pktin
.type
, ssh2_pkt_type(pktin
.type
),
991 pktin
.data
+6, pktin
.length
-6);
993 switch (pktin
.type
) {
995 * These packets we must handle instantly.
997 case SSH2_MSG_DISCONNECT
:
999 /* log reason code in disconnect message */
1001 int reason
= GET_32BIT(pktin
.data
+ 6);
1002 unsigned msglen
= GET_32BIT(pktin
.data
+ 10);
1004 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1005 sprintf(buf
, "Received disconnect message (%s)",
1006 ssh2_disconnect_reasons
[reason
]);
1008 sprintf(buf
, "Received disconnect message (unknown type %d)",
1012 strcpy(buf
, "Disconnection message text: ");
1013 nowlen
= strlen(buf
);
1014 if (msglen
> sizeof(buf
) - nowlen
- 1)
1015 msglen
= sizeof(buf
) - nowlen
- 1;
1016 memcpy(buf
+ nowlen
, pktin
.data
+ 14, msglen
);
1017 buf
[nowlen
+ msglen
] = '\0';
1019 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1021 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1022 ssh2_disconnect_reasons
[reason
] : "unknown",
1027 case SSH2_MSG_IGNORE
:
1029 case SSH2_MSG_DEBUG
:
1031 /* log the debug message */
1033 /* int display = pktin.body[6]; */
1034 int stringlen
= GET_32BIT(pktin
.data
+7);
1036 strcpy(buf
, "Remote debug message: ");
1037 prefix
= strlen(buf
);
1038 if (stringlen
> sizeof(buf
)-prefix
-1)
1039 stringlen
= sizeof(buf
)-prefix
-1;
1040 memcpy(buf
+ prefix
, pktin
.data
+ 11, stringlen
);
1041 buf
[prefix
+ stringlen
] = '\0';
1044 goto next_packet
; /* FIXME: print the debug message */
1047 * These packets we need do nothing about here.
1049 case SSH2_MSG_UNIMPLEMENTED
:
1050 case SSH2_MSG_SERVICE_REQUEST
:
1051 case SSH2_MSG_SERVICE_ACCEPT
:
1052 case SSH2_MSG_KEXINIT
:
1053 case SSH2_MSG_NEWKEYS
:
1054 case SSH2_MSG_KEXDH_INIT
:
1055 case SSH2_MSG_KEXDH_REPLY
:
1056 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1057 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1058 case SSH2_MSG_KEX_DH_GEX_INIT
:
1059 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1060 case SSH2_MSG_USERAUTH_REQUEST
:
1061 case SSH2_MSG_USERAUTH_FAILURE
:
1062 case SSH2_MSG_USERAUTH_SUCCESS
:
1063 case SSH2_MSG_USERAUTH_BANNER
:
1064 case SSH2_MSG_USERAUTH_PK_OK
:
1065 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1066 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1067 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1068 case SSH2_MSG_GLOBAL_REQUEST
:
1069 case SSH2_MSG_REQUEST_SUCCESS
:
1070 case SSH2_MSG_REQUEST_FAILURE
:
1071 case SSH2_MSG_CHANNEL_OPEN
:
1072 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1073 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1074 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1075 case SSH2_MSG_CHANNEL_DATA
:
1076 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1077 case SSH2_MSG_CHANNEL_EOF
:
1078 case SSH2_MSG_CHANNEL_CLOSE
:
1079 case SSH2_MSG_CHANNEL_REQUEST
:
1080 case SSH2_MSG_CHANNEL_SUCCESS
:
1081 case SSH2_MSG_CHANNEL_FAILURE
:
1085 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1088 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
1089 ssh2_pkt_adduint32(st
->incoming_sequence
- 1);
1097 static void ssh1_pktout_size(int len
)
1101 len
+= 5; /* type and CRC */
1102 pad
= 8 - (len
% 8);
1105 pktout
.length
= len
- 5;
1106 if (pktout
.maxlen
< biglen
) {
1107 pktout
.maxlen
= biglen
;
1109 /* Allocate enough buffer space for extra block
1110 * for MS CryptEncrypt() */
1111 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 12) :
1112 srealloc(pktout
.data
, biglen
+ 12));
1114 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 4) :
1115 srealloc(pktout
.data
, biglen
+ 4));
1118 fatalbox("Out of memory");
1120 pktout
.body
= pktout
.data
+ 4 + pad
+ 1;
1123 static void s_wrpkt_start(int type
, int len
)
1125 ssh1_pktout_size(len
);
1129 static int s_wrpkt_prepare(void)
1131 int pad
, len
, biglen
, i
;
1134 pktout
.body
[-1] = pktout
.type
;
1136 log_packet(PKT_OUTGOING
, pktout
.type
, ssh1_pkt_type(pktout
.type
),
1137 pktout
.body
, pktout
.length
);
1139 if (ssh1_compressing
) {
1140 unsigned char *compblk
;
1142 zlib_compress_block(pktout
.body
- 1, pktout
.length
+ 1,
1143 &compblk
, &complen
);
1144 ssh1_pktout_size(complen
- 1);
1145 memcpy(pktout
.body
- 1, compblk
, complen
);
1149 len
= pktout
.length
+ 5; /* type and CRC */
1150 pad
= 8 - (len
% 8);
1153 for (i
= 0; i
< pad
; i
++)
1154 pktout
.data
[i
+ 4] = random_byte();
1155 crc
= crc32(pktout
.data
+ 4, biglen
- 4);
1156 PUT_32BIT(pktout
.data
+ biglen
, crc
);
1157 PUT_32BIT(pktout
.data
, len
);
1160 cipher
->encrypt(pktout
.data
+ 4, biglen
);
1165 static void s_wrpkt(void)
1168 len
= s_wrpkt_prepare();
1169 backlog
= sk_write(s
, pktout
.data
, len
);
1170 if (backlog
> SSH_MAX_BACKLOG
)
1171 ssh_throttle_all(1, backlog
);
1174 static void s_wrpkt_defer(void)
1177 len
= s_wrpkt_prepare();
1178 if (deferred_len
+ len
> deferred_size
) {
1179 deferred_size
= deferred_len
+ len
+ 128;
1180 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1182 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1183 deferred_len
+= len
;
1187 * Construct a packet with the specified contents.
1189 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
1191 unsigned char *p
, *argp
, argchar
;
1192 unsigned long argint
;
1193 int pktlen
, argtype
, arglen
;
1197 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1200 (void) va_arg(ap1
, int);
1204 (void) va_arg(ap1
, char);
1208 (void) va_arg(ap1
, unsigned char *);
1209 arglen
= va_arg(ap1
, int);
1213 argp
= va_arg(ap1
, unsigned char *);
1214 arglen
= strlen(argp
);
1215 pktlen
+= 4 + arglen
;
1218 bn
= va_arg(ap1
, Bignum
);
1219 pktlen
+= ssh1_bignum_length(bn
);
1226 s_wrpkt_start(pkttype
, pktlen
);
1229 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1232 argint
= va_arg(ap2
, int);
1233 PUT_32BIT(p
, argint
);
1237 argchar
= va_arg(ap2
, unsigned char);
1242 argp
= va_arg(ap2
, unsigned char *);
1243 arglen
= va_arg(ap2
, int);
1244 memcpy(p
, argp
, arglen
);
1248 argp
= va_arg(ap2
, unsigned char *);
1249 arglen
= strlen(argp
);
1250 PUT_32BIT(p
, arglen
);
1251 memcpy(p
+ 4, argp
, arglen
);
1255 bn
= va_arg(ap2
, Bignum
);
1256 p
+= ssh1_write_bignum(p
, bn
);
1262 static void send_packet(int pkttype
, ...)
1265 va_start(ap1
, pkttype
);
1266 va_start(ap2
, pkttype
);
1267 construct_packet(pkttype
, ap1
, ap2
);
1271 static void defer_packet(int pkttype
, ...)
1274 va_start(ap1
, pkttype
);
1275 va_start(ap2
, pkttype
);
1276 construct_packet(pkttype
, ap1
, ap2
);
1280 static int ssh_versioncmp(char *a
, char *b
)
1283 unsigned long av
, bv
;
1285 av
= strtoul(a
, &ae
, 10);
1286 bv
= strtoul(b
, &be
, 10);
1288 return (av
< bv ?
-1 : +1);
1293 av
= strtoul(ae
, &ae
, 10);
1294 bv
= strtoul(be
, &be
, 10);
1296 return (av
< bv ?
-1 : +1);
1302 * Utility routines for putting an SSH-protocol `string' and
1303 * `uint32' into a SHA state.
1306 static void sha_string(SHA_State
* s
, void *str
, int len
)
1308 unsigned char lenblk
[4];
1309 PUT_32BIT(lenblk
, len
);
1310 SHA_Bytes(s
, lenblk
, 4);
1311 SHA_Bytes(s
, str
, len
);
1314 static void sha_uint32(SHA_State
* s
, unsigned i
)
1316 unsigned char intblk
[4];
1317 PUT_32BIT(intblk
, i
);
1318 SHA_Bytes(s
, intblk
, 4);
1322 * SSH2 packet construction functions.
1324 static void ssh2_pkt_ensure(int length
)
1326 if (pktout
.maxlen
< length
) {
1327 pktout
.maxlen
= length
+ 256;
1330 NULL ?
smalloc(pktout
.maxlen
+
1331 APIEXTRA
) : srealloc(pktout
.data
,
1335 fatalbox("Out of memory");
1338 static void ssh2_pkt_adddata(void *data
, int len
)
1340 pktout
.length
+= len
;
1341 ssh2_pkt_ensure(pktout
.length
);
1342 memcpy(pktout
.data
+ pktout
.length
- len
, data
, len
);
1344 static void ssh2_pkt_addbyte(unsigned char byte
)
1346 ssh2_pkt_adddata(&byte
, 1);
1348 static void ssh2_pkt_init(int pkt_type
)
1351 ssh2_pkt_addbyte((unsigned char) pkt_type
);
1353 static void ssh2_pkt_addbool(unsigned char value
)
1355 ssh2_pkt_adddata(&value
, 1);
1357 static void ssh2_pkt_adduint32(unsigned long value
)
1360 PUT_32BIT(x
, value
);
1361 ssh2_pkt_adddata(x
, 4);
1363 static void ssh2_pkt_addstring_start(void)
1365 ssh2_pkt_adduint32(0);
1366 pktout
.savedpos
= pktout
.length
;
1368 static void ssh2_pkt_addstring_str(char *data
)
1370 ssh2_pkt_adddata(data
, strlen(data
));
1371 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1372 pktout
.length
- pktout
.savedpos
);
1374 static void ssh2_pkt_addstring_data(char *data
, int len
)
1376 ssh2_pkt_adddata(data
, len
);
1377 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1378 pktout
.length
- pktout
.savedpos
);
1380 static void ssh2_pkt_addstring(char *data
)
1382 ssh2_pkt_addstring_start();
1383 ssh2_pkt_addstring_str(data
);
1385 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1388 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1391 fatalbox("out of memory");
1393 for (i
= 1; i
<= n
; i
++)
1394 p
[i
] = bignum_byte(b
, n
- i
);
1396 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1398 memmove(p
, p
+ i
, n
+ 1 - i
);
1402 static void ssh2_pkt_addmp(Bignum b
)
1406 p
= ssh2_mpint_fmt(b
, &len
);
1407 ssh2_pkt_addstring_start();
1408 ssh2_pkt_addstring_data(p
, len
);
1413 * Construct an SSH2 final-form packet: compress it, encrypt it,
1414 * put the MAC on it. Final packet, ready to be sent, is stored in
1415 * pktout.data. Total length is returned.
1417 static int ssh2_pkt_construct(void)
1419 int cipherblk
, maclen
, padding
, i
;
1420 static unsigned long outgoing_sequence
= 0;
1422 log_packet(PKT_OUTGOING
, pktout
.data
[5], ssh2_pkt_type(pktout
.data
[5]),
1423 pktout
.data
+ 6, pktout
.length
- 6);
1426 * Compress packet payload.
1429 unsigned char *newpayload
;
1431 if (cscomp
&& cscomp
->compress(pktout
.data
+ 5, pktout
.length
- 5,
1432 &newpayload
, &newlen
)) {
1434 ssh2_pkt_adddata(newpayload
, newlen
);
1440 * Add padding. At least four bytes, and must also bring total
1441 * length (minus MAC) up to a multiple of the block size.
1443 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
1444 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1447 (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1448 maclen
= csmac ? csmac
->len
: 0;
1449 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
1450 pktout
.data
[4] = padding
;
1451 for (i
= 0; i
< padding
; i
++)
1452 pktout
.data
[pktout
.length
+ i
] = random_byte();
1453 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
1455 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
1457 outgoing_sequence
++; /* whether or not we MACed */
1460 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
1462 /* Ready-to-send packet starts at pktout.data. We return length. */
1463 return pktout
.length
+ padding
+ maclen
;
1467 * Construct and send an SSH2 packet immediately.
1469 static void ssh2_pkt_send(void)
1473 len
= ssh2_pkt_construct();
1474 backlog
= sk_write(s
, pktout
.data
, len
);
1475 if (backlog
> SSH_MAX_BACKLOG
)
1476 ssh_throttle_all(1, backlog
);
1480 * Construct an SSH2 packet and add it to a deferred data block.
1481 * Useful for sending multiple packets in a single sk_write() call,
1482 * to prevent a traffic-analysing listener from being able to work
1483 * out the length of any particular packet (such as the password
1486 * Note that because SSH2 sequence-numbers its packets, this can
1487 * NOT be used as an m4-style `defer' allowing packets to be
1488 * constructed in one order and sent in another.
1490 static void ssh2_pkt_defer(void)
1492 int len
= ssh2_pkt_construct();
1493 if (deferred_len
+ len
> deferred_size
) {
1494 deferred_size
= deferred_len
+ len
+ 128;
1495 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1497 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1498 deferred_len
+= len
;
1502 * Send the whole deferred data block constructed by
1503 * ssh2_pkt_defer() or SSH1's defer_packet().
1505 static void ssh_pkt_defersend(void)
1508 backlog
= sk_write(s
, deferred_send_data
, deferred_len
);
1509 deferred_len
= deferred_size
= 0;
1510 sfree(deferred_send_data
);
1511 deferred_send_data
= NULL
;
1512 if (backlog
> SSH_MAX_BACKLOG
)
1513 ssh_throttle_all(1, backlog
);
1517 void bndebug(char *string
, Bignum b
)
1521 p
= ssh2_mpint_fmt(b
, &len
);
1522 debug(("%s", string
));
1523 for (i
= 0; i
< len
; i
++)
1524 debug((" %02x", p
[i
]));
1530 static void sha_mpint(SHA_State
* s
, Bignum b
)
1534 p
= ssh2_mpint_fmt(b
, &len
);
1535 sha_string(s
, p
, len
);
1540 * SSH2 packet decode functions.
1542 static unsigned long ssh2_pkt_getuint32(void)
1544 unsigned long value
;
1545 if (pktin
.length
- pktin
.savedpos
< 4)
1546 return 0; /* arrgh, no way to decline (FIXME?) */
1547 value
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1548 pktin
.savedpos
+= 4;
1551 static int ssh2_pkt_getbool(void)
1553 unsigned long value
;
1554 if (pktin
.length
- pktin
.savedpos
< 1)
1555 return 0; /* arrgh, no way to decline (FIXME?) */
1556 value
= pktin
.data
[pktin
.savedpos
] != 0;
1560 static void ssh2_pkt_getstring(char **p
, int *length
)
1564 if (pktin
.length
- pktin
.savedpos
< 4)
1566 *length
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1567 pktin
.savedpos
+= 4;
1568 if (pktin
.length
- pktin
.savedpos
< *length
)
1570 *p
= pktin
.data
+ pktin
.savedpos
;
1571 pktin
.savedpos
+= *length
;
1573 static Bignum
ssh2_pkt_getmp(void)
1579 ssh2_pkt_getstring(&p
, &length
);
1583 bombout(("internal error: Can't handle negative mpints"));
1586 b
= bignum_from_bytes(p
, length
);
1591 * Helper function to add an SSH2 signature blob to a packet.
1592 * Expects to be shown the public key blob as well as the signature
1593 * blob. Normally works just like ssh2_pkt_addstring, but will
1594 * fiddle with the signature packet if necessary for
1595 * BUG_SSH2_RSA_PADDING.
1597 static void ssh2_add_sigblob(void *pkblob_v
, int pkblob_len
,
1598 void *sigblob_v
, int sigblob_len
)
1600 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1601 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1603 /* dmemdump(pkblob, pkblob_len); */
1604 /* dmemdump(sigblob, sigblob_len); */
1607 * See if this is in fact an ssh-rsa signature and a buggy
1608 * server; otherwise we can just do this the easy way.
1610 if ((ssh_remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1611 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1612 int pos
, len
, siglen
;
1615 * Find the byte length of the modulus.
1618 pos
= 4+7; /* skip over "ssh-rsa" */
1619 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1620 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1621 pos
+= 4; /* find modulus itself */
1622 while (len
> 0 && pkblob
[pos
] == 0)
1624 /* debug(("modulus length is %d\n", len)); */
1627 * Now find the signature integer.
1629 pos
= 4+7; /* skip over "ssh-rsa" */
1630 siglen
= GET_32BIT(sigblob
+pos
);
1631 /* debug(("signature length is %d\n", siglen)); */
1633 if (len
!= siglen
) {
1634 unsigned char newlen
[4];
1635 ssh2_pkt_addstring_start();
1636 ssh2_pkt_addstring_data(sigblob
, pos
);
1637 /* dmemdump(sigblob, pos); */
1638 pos
+= 4; /* point to start of actual sig */
1639 PUT_32BIT(newlen
, len
);
1640 ssh2_pkt_addstring_data(newlen
, 4);
1641 /* dmemdump(newlen, 4); */
1643 while (len
-- > siglen
) {
1644 ssh2_pkt_addstring_data(newlen
, 1);
1645 /* dmemdump(newlen, 1); */
1647 ssh2_pkt_addstring_data(sigblob
+pos
, siglen
);
1648 /* dmemdump(sigblob+pos, siglen); */
1652 /* Otherwise fall through and do it the easy way. */
1655 ssh2_pkt_addstring_start();
1656 ssh2_pkt_addstring_data(sigblob
, sigblob_len
);
1660 * Examine the remote side's version string and compare it against
1661 * a list of known buggy implementations.
1663 static void ssh_detect_bugs(char *vstring
)
1665 char *imp
; /* pointer to implementation part */
1667 imp
+= strcspn(imp
, "-");
1669 imp
+= strcspn(imp
, "-");
1672 ssh_remote_bugs
= 0;
1674 if (cfg
.sshbug_ignore1
== BUG_ON
||
1675 (cfg
.sshbug_ignore1
== BUG_AUTO
&&
1676 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1677 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1678 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")))) {
1680 * These versions don't support SSH1_MSG_IGNORE, so we have
1681 * to use a different defence against password length
1684 ssh_remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1685 logevent("We believe remote version has SSH1 ignore bug");
1688 if (cfg
.sshbug_plainpw1
== BUG_ON
||
1689 (cfg
.sshbug_plainpw1
== BUG_AUTO
&&
1690 (!strcmp(imp
, "Cisco-1.25")))) {
1692 * These versions need a plain password sent; they can't
1693 * handle having a null and a random length of data after
1696 ssh_remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1697 logevent("We believe remote version needs a plain SSH1 password");
1700 if (cfg
.sshbug_rsa1
== BUG_ON
||
1701 (cfg
.sshbug_rsa1
== BUG_AUTO
&&
1702 (!strcmp(imp
, "Cisco-1.25")))) {
1704 * These versions apparently have no clue whatever about
1705 * RSA authentication and will panic and die if they see
1706 * an AUTH_RSA message.
1708 ssh_remote_bugs
|= BUG_CHOKES_ON_RSA
;
1709 logevent("We believe remote version can't handle RSA authentication");
1712 if (cfg
.sshbug_hmac2
== BUG_ON
||
1713 (cfg
.sshbug_hmac2
== BUG_AUTO
&&
1714 (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1715 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1716 !strncmp(imp
, "2.1 ", 4)))) {
1718 * These versions have the HMAC bug.
1720 ssh_remote_bugs
|= BUG_SSH2_HMAC
;
1721 logevent("We believe remote version has SSH2 HMAC bug");
1724 if (cfg
.sshbug_derivekey2
== BUG_ON
||
1725 (cfg
.sshbug_derivekey2
== BUG_AUTO
&&
1726 (!strncmp(imp
, "2.0.", 4)))) {
1728 * These versions have the key-derivation bug (failing to
1729 * include the literal shared secret in the hashes that
1730 * generate the keys).
1732 ssh_remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1733 logevent("We believe remote version has SSH2 key-derivation bug");
1736 if (cfg
.sshbug_rsapad2
== BUG_ON
||
1737 (cfg
.sshbug_rsapad2
== BUG_AUTO
&&
1738 ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1739 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')))){
1741 * These versions have the SSH2 RSA padding bug.
1743 ssh_remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1744 logevent("We believe remote version has SSH2 RSA padding bug");
1747 if (cfg
.sshbug_dhgex2
== BUG_ON
) {
1749 * These versions have the SSH2 DH GEX bug.
1751 ssh_remote_bugs
|= BUG_SSH2_DH_GEX
;
1752 logevent("We believe remote version has SSH2 DH group exchange bug");
1756 static int do_ssh_init(unsigned char c
)
1759 static char version
[10];
1760 static char *vstring
;
1761 static int vstrsize
;
1764 static int proto1
, proto2
;
1768 /* Search for the string "SSH-" in the input. */
1771 static const int transS
[] = { 1, 2, 2, 1 };
1772 static const int transH
[] = { 0, 0, 3, 0 };
1773 static const int transminus
[] = { 0, 0, 0, -1 };
1784 crReturn(1); /* get another character */
1788 vstring
= smalloc(vstrsize
);
1789 strcpy(vstring
, "SSH-");
1793 crReturn(1); /* get another char */
1794 if (vslen
>= vstrsize
- 1) {
1796 vstring
= srealloc(vstring
, vstrsize
);
1798 vstring
[vslen
++] = c
;
1803 } else if (i
< sizeof(version
) - 1)
1805 } else if (c
== '\n')
1809 ssh_agentfwd_enabled
= FALSE
;
1810 rdpkt2_state
.incoming_sequence
= 0;
1813 vlog
= smalloc(20 + vslen
);
1814 vstring
[strcspn (vstring
, "\r\n")] = '\0'; /* remove end-of-line chars */
1815 sprintf(vlog
, "Server version: %s", vstring
);
1817 ssh_detect_bugs(vstring
);
1821 * Decide which SSH protocol version to support.
1824 /* Anything strictly below "2.0" means protocol 1 is supported. */
1825 proto1
= ssh_versioncmp(version
, "2.0") < 0;
1826 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1827 proto2
= ssh_versioncmp(version
, "1.99") >= 0;
1829 if (cfg
.sshprot
== 0 && !proto1
) {
1830 bombout(("SSH protocol version 1 required by user but not provided by server"));
1833 if (cfg
.sshprot
== 3 && !proto2
) {
1834 bombout(("SSH protocol version 2 required by user but not provided by server"));
1838 if (proto2
&& (cfg
.sshprot
>= 2 || !proto1
)) {
1842 char verstring
[80], vlog
[100];
1843 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1844 SHA_Init(&exhashbase
);
1846 * Hash our version string and their version string.
1848 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1849 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1850 sprintf(vlog
, "We claim version: %s", verstring
);
1852 strcat(verstring
, "\n");
1853 logevent("Using SSH protocol version 2");
1854 sk_write(s
, verstring
, strlen(verstring
));
1855 ssh_protocol
= ssh2_protocol
;
1857 s_rdpkt
= ssh2_rdpkt
;
1862 char verstring
[80], vlog
[100];
1863 sprintf(verstring
, "SSH-%s-%s",
1864 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"),
1866 sprintf(vlog
, "We claim version: %s", verstring
);
1868 strcat(verstring
, "\n");
1870 logevent("Using SSH protocol version 1");
1871 sk_write(s
, verstring
, strlen(verstring
));
1872 ssh_protocol
= ssh1_protocol
;
1874 s_rdpkt
= ssh1_rdpkt
;
1876 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1883 static void ssh_gotdata(unsigned char *data
, int datalen
)
1888 * To begin with, feed the characters one by one to the
1889 * protocol initialisation / selection function do_ssh_init().
1890 * When that returns 0, we're done with the initial greeting
1891 * exchange and can move on to packet discipline.
1896 crReturnV
; /* more data please */
1897 ret
= do_ssh_init(*data
);
1905 * We emerge from that loop when the initial negotiation is
1906 * over and we have selected an s_rdpkt function. Now pass
1907 * everything to s_rdpkt, and then pass the resulting packets
1908 * to the proper protocol handler.
1913 while (datalen
> 0) {
1914 if (s_rdpkt(&data
, &datalen
) == 0) {
1915 if (ssh_state
== SSH_STATE_CLOSED
) {
1918 ssh_protocol(NULL
, 0, 1);
1919 if (ssh_state
== SSH_STATE_CLOSED
) {
1929 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1932 ssh_state
= SSH_STATE_CLOSED
;
1938 /* A socket error has occurred. */
1939 logevent(error_msg
);
1940 connection_fatal(error_msg
);
1942 /* Otherwise, the remote side closed the connection normally. */
1947 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1949 ssh_gotdata(data
, len
);
1950 if (ssh_state
== SSH_STATE_CLOSED
) {
1960 static void ssh_sent(Plug plug
, int bufsize
)
1963 * If the send backlog on the SSH socket itself clears, we
1964 * should unthrottle the whole world if it was throttled.
1966 if (bufsize
< SSH_MAX_BACKLOG
)
1967 ssh_throttle_all(0, bufsize
);
1971 * Connect to specified host and port.
1972 * Returns an error message, or NULL on success.
1973 * Also places the canonical host name into `realhost'. It must be
1974 * freed by the caller.
1976 static char *connect_to_host(char *host
, int port
, char **realhost
, int nodelay
)
1978 static struct plug_function_table fn_table
= {
1983 }, *fn_table_ptr
= &fn_table
;
1992 savedhost
= smalloc(1 + strlen(host
));
1994 fatalbox("Out of memory");
1995 strcpy(savedhost
, host
);
1998 port
= 22; /* default ssh port */
2013 sprintf(buf
, "Looking up host \"%.170s\"", host
);
2016 addr
= sk_namelookup(host
, realhost
);
2017 if ((err
= sk_addr_error(addr
)))
2021 *realhost
= strdup(FWhost
);
2028 char buf
[200], addrbuf
[100];
2029 sk_getaddr(addr
, addrbuf
, 100);
2030 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
2033 s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, &fn_table_ptr
);
2034 if ((err
= sk_socket_error(s
))) {
2040 sk_write(s
, "connect ", 8);
2041 sk_write(s
, FWhost
, strlen(FWhost
));
2044 sprintf(buf
, " %d\n", FWport
);
2045 sk_write(s
, buf
, strlen(buf
));
2053 * Throttle or unthrottle the SSH connection.
2055 static void ssh1_throttle(int adjust
)
2057 int old_count
= ssh1_throttle_count
;
2058 ssh1_throttle_count
+= adjust
;
2059 assert(ssh1_throttle_count
>= 0);
2060 if (ssh1_throttle_count
&& !old_count
) {
2061 sk_set_frozen(s
, 1);
2062 } else if (!ssh1_throttle_count
&& old_count
) {
2063 sk_set_frozen(s
, 0);
2068 * Throttle or unthrottle _all_ local data streams (for when sends
2069 * on the SSH connection itself back up).
2071 static void ssh_throttle_all(int enable
, int bufsize
)
2074 struct ssh_channel
*c
;
2076 if (enable
== ssh_throttled_all
)
2078 ssh_throttled_all
= enable
;
2079 ssh_overall_bufsize
= bufsize
;
2082 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
2084 case CHAN_MAINSESSION
:
2086 * This is treated separately, outside the switch.
2090 x11_override_throttle(c
->u
.x11
.s
, enable
);
2093 /* Agent channels require no buffer management. */
2096 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2103 * Username and password input, abstracted off into reusable
2104 * routines (hopefully even reusable between SSH1 and SSH2!).
2106 static char *ssh_userpass_input_buffer
;
2107 static int ssh_userpass_input_buflen
;
2108 static int ssh_userpass_input_bufpos
;
2109 static int ssh_userpass_input_echo
;
2111 /* Set up a username or password input loop on a given buffer. */
2112 void setup_userpass_input(char *buffer
, int buflen
, int echo
)
2114 ssh_userpass_input_buffer
= buffer
;
2115 ssh_userpass_input_buflen
= buflen
;
2116 ssh_userpass_input_bufpos
= 0;
2117 ssh_userpass_input_echo
= echo
;
2121 * Process some terminal data in the course of username/password
2122 * input. Returns >0 for success (line of input returned in
2123 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2124 * for inconclusive (keep waiting for more input please).
2126 int process_userpass_input(unsigned char *in
, int inlen
)
2131 switch (c
= *in
++) {
2134 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
] = 0;
2135 ssh_userpass_input_buffer
[ssh_userpass_input_buflen
-1] = 0;
2140 if (ssh_userpass_input_bufpos
> 0) {
2141 if (ssh_userpass_input_echo
)
2142 c_write_str("\b \b");
2143 ssh_userpass_input_bufpos
--;
2148 while (ssh_userpass_input_bufpos
> 0) {
2149 if (ssh_userpass_input_echo
)
2150 c_write_str("\b \b");
2151 ssh_userpass_input_bufpos
--;
2159 if (((c
>= ' ' && c
<= '~') ||
2160 ((unsigned char) c
>= 160))
2161 && ssh_userpass_input_bufpos
< ssh_userpass_input_buflen
-1) {
2162 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
++] = c
;
2163 if (ssh_userpass_input_echo
)
2173 * Handle the key exchange and user authentication phases.
2175 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
2179 static unsigned char *rsabuf
, *keystr1
, *keystr2
;
2180 unsigned char cookie
[8];
2181 struct RSAKey servkey
, hostkey
;
2182 struct MD5Context md5c
;
2183 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
2184 static int tried_publickey
, tried_agent
;
2185 static int tis_auth_refused
, ccard_auth_refused
;
2186 static unsigned char session_id
[16];
2187 static int cipher_type
;
2188 static char username
[100];
2189 static void *publickey_blob
;
2190 int publickey_bloblen
;
2197 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2198 bombout(("Public key packet not received"));
2202 logevent("Received public keys");
2204 memcpy(cookie
, pktin
.body
, 8);
2206 i
= makekey(pktin
.body
+ 8, &servkey
, &keystr1
, 0);
2207 j
= makekey(pktin
.body
+ 8 + i
, &hostkey
, &keystr2
, 0);
2210 * Log the host key fingerprint.
2214 logevent("Host key fingerprint is:");
2215 strcpy(logmsg
, " ");
2216 hostkey
.comment
= NULL
;
2217 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2218 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2222 ssh1_remote_protoflags
= GET_32BIT(pktin
.body
+ 8 + i
+ j
);
2223 supported_ciphers_mask
= GET_32BIT(pktin
.body
+ 12 + i
+ j
);
2224 supported_auths_mask
= GET_32BIT(pktin
.body
+ 16 + i
+ j
);
2226 ssh1_local_protoflags
=
2227 ssh1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2228 ssh1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2231 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
2232 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
2233 MD5Update(&md5c
, pktin
.body
, 8);
2234 MD5Final(session_id
, &md5c
);
2236 for (i
= 0; i
< 32; i
++)
2237 session_key
[i
] = random_byte();
2239 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2241 rsabuf
= smalloc(len
);
2243 fatalbox("Out of memory");
2246 * Verify the host key.
2250 * First format the key into a string.
2252 int len
= rsastr_len(&hostkey
);
2253 char fingerprint
[100];
2254 char *keystr
= smalloc(len
);
2256 fatalbox("Out of memory");
2257 rsastr_fmt(keystr
, &hostkey
);
2258 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2259 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
,
2264 for (i
= 0; i
< 32; i
++) {
2265 rsabuf
[i
] = session_key
[i
];
2267 rsabuf
[i
] ^= session_id
[i
];
2270 if (hostkey
.bytes
> servkey
.bytes
) {
2271 rsaencrypt(rsabuf
, 32, &servkey
);
2272 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
2274 rsaencrypt(rsabuf
, 32, &hostkey
);
2275 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
2278 logevent("Encrypted session key");
2281 int cipher_chosen
= 0, warn
= 0;
2282 char *cipher_string
= NULL
;
2283 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2284 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2285 if (next_cipher
== CIPHER_WARN
) {
2286 /* If/when we choose a cipher, warn about it */
2288 } else if (next_cipher
== CIPHER_AES
) {
2289 /* XXX Probably don't need to mention this. */
2290 logevent("AES not supported in SSH1, skipping");
2292 switch (next_cipher
) {
2293 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
;
2294 cipher_string
= "3DES"; break;
2295 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
;
2296 cipher_string
= "Blowfish"; break;
2297 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
;
2298 cipher_string
= "single-DES"; break;
2300 if (supported_ciphers_mask
& (1 << cipher_type
))
2304 if (!cipher_chosen
) {
2305 if ((supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2306 bombout(("Server violates SSH 1 protocol by not "
2307 "supporting 3DES encryption"));
2309 /* shouldn't happen */
2310 bombout(("No supported ciphers found"));
2314 /* Warn about chosen cipher if necessary. */
2316 askcipher(cipher_string
, 0);
2319 switch (cipher_type
) {
2320 case SSH_CIPHER_3DES
:
2321 logevent("Using 3DES encryption");
2323 case SSH_CIPHER_DES
:
2324 logevent("Using single-DES encryption");
2326 case SSH_CIPHER_BLOWFISH
:
2327 logevent("Using Blowfish encryption");
2331 send_packet(SSH1_CMSG_SESSION_KEY
,
2332 PKT_CHAR
, cipher_type
,
2333 PKT_DATA
, cookie
, 8,
2334 PKT_CHAR
, (len
* 8) >> 8, PKT_CHAR
, (len
* 8) & 0xFF,
2335 PKT_DATA
, rsabuf
, len
,
2336 PKT_INT
, ssh1_local_protoflags
, PKT_END
);
2338 logevent("Trying to enable encryption...");
2342 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2343 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
: &ssh_3des
;
2344 cipher
->sesskey(session_key
);
2348 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2349 bombout(("Encryption not successfully enabled"));
2353 logevent("Successfully started encryption");
2357 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2358 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2359 if (!ssh_get_line("login as: ",
2360 username
, sizeof(username
), FALSE
)) {
2362 * get_line failed to get a username.
2365 logevent("No username provided. Abandoning session.");
2366 ssh_state
= SSH_STATE_CLOSED
;
2371 c_write_str("login as: ");
2374 setup_userpass_input(username
, sizeof(username
), 1);
2376 crWaitUntil(!ispkt
);
2377 ret
= process_userpass_input(in
, inlen
);
2381 c_write_str("\r\n");
2384 strncpy(username
, cfg
.username
, sizeof(username
));
2385 username
[sizeof(username
)-1] = '\0';
2388 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
2390 char userlog
[22 + sizeof(username
)];
2391 sprintf(userlog
, "Sent username \"%s\"", username
);
2393 if (flags
& FLAG_INTERACTIVE
&&
2394 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2395 strcat(userlog
, "\r\n");
2396 c_write_str(userlog
);
2403 if ((ssh_remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2404 /* We must not attempt PK auth. Pretend we've already tried it. */
2405 tried_publickey
= tried_agent
= 1;
2407 tried_publickey
= tried_agent
= 0;
2409 tis_auth_refused
= ccard_auth_refused
= 0;
2410 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2412 if (!rsakey_pubblob(cfg
.keyfile
, &publickey_blob
, &publickey_bloblen
))
2413 publickey_blob
= NULL
;
2415 publickey_blob
= NULL
;
2417 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
2418 static char password
[100];
2419 static char prompt
[200];
2422 static int pwpkt_type
;
2423 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2425 if (agent_exists() && !tried_agent
) {
2427 * Attempt RSA authentication using Pageant.
2429 static unsigned char request
[5], *response
, *p
;
2430 static int responselen
;
2431 static int i
, nkeys
;
2432 static int authed
= FALSE
;
2436 logevent("Pageant is running. Requesting keys.");
2438 /* Request the keys held by the agent. */
2439 PUT_32BIT(request
, 1);
2440 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2441 agent_query(request
, 5, &r
, &responselen
);
2442 response
= (unsigned char *) r
;
2443 if (response
&& responselen
>= 5 &&
2444 response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2446 nkeys
= GET_32BIT(p
);
2450 sprintf(buf
, "Pageant has %d SSH1 keys", nkeys
);
2453 for (i
= 0; i
< nkeys
; i
++) {
2454 static struct RSAKey key
;
2455 static Bignum challenge
;
2456 static char *commentp
;
2457 static int commentlen
;
2461 sprintf(buf
, "Trying Pageant key #%d", i
);
2464 if (publickey_blob
&&
2465 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
2466 logevent("This key matches configured key file");
2467 tried_publickey
= 1;
2470 p
+= ssh1_read_bignum(p
, &key
.exponent
);
2471 p
+= ssh1_read_bignum(p
, &key
.modulus
);
2472 commentlen
= GET_32BIT(p
);
2476 send_packet(SSH1_CMSG_AUTH_RSA
,
2477 PKT_BIGNUM
, key
.modulus
, PKT_END
);
2479 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2480 logevent("Key refused");
2483 logevent("Received RSA challenge");
2484 ssh1_read_bignum(pktin
.body
, &challenge
);
2486 char *agentreq
, *q
, *ret
;
2489 len
= 1 + 4; /* message type, bit count */
2490 len
+= ssh1_bignum_length(key
.exponent
);
2491 len
+= ssh1_bignum_length(key
.modulus
);
2492 len
+= ssh1_bignum_length(challenge
);
2493 len
+= 16; /* session id */
2494 len
+= 4; /* response format */
2495 agentreq
= smalloc(4 + len
);
2496 PUT_32BIT(agentreq
, len
);
2498 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2499 PUT_32BIT(q
, bignum_bitcount(key
.modulus
));
2501 q
+= ssh1_write_bignum(q
, key
.exponent
);
2502 q
+= ssh1_write_bignum(q
, key
.modulus
);
2503 q
+= ssh1_write_bignum(q
, challenge
);
2504 memcpy(q
, session_id
, 16);
2506 PUT_32BIT(q
, 1); /* response format */
2507 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2511 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2512 logevent("Sending Pageant's response");
2513 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2514 PKT_DATA
, ret
+ 5, 16,
2518 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2520 ("Pageant's response accepted");
2521 if (flags
& FLAG_VERBOSE
) {
2523 ("Authenticated using RSA key \"");
2524 c_write(commentp
, commentlen
);
2525 c_write_str("\" from agent\r\n");
2530 ("Pageant's response not accepted");
2533 ("Pageant failed to answer challenge");
2537 logevent("No reply received from Pageant");
2540 freebn(key
.exponent
);
2541 freebn(key
.modulus
);
2550 if (*cfg
.keyfile
&& !tried_publickey
)
2551 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2553 if (cfg
.try_tis_auth
&&
2554 (supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2555 !tis_auth_refused
) {
2556 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2557 logevent("Requested TIS authentication");
2558 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
2560 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2561 logevent("TIS authentication declined");
2562 if (flags
& FLAG_INTERACTIVE
)
2563 c_write_str("TIS authentication refused.\r\n");
2564 tis_auth_refused
= 1;
2567 int challengelen
= ((pktin
.body
[0] << 24) |
2568 (pktin
.body
[1] << 16) |
2569 (pktin
.body
[2] << 8) |
2571 logevent("Received TIS challenge");
2572 if (challengelen
> sizeof(prompt
) - 1)
2573 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2574 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2575 /* Prompt heuristic comes from OpenSSH */
2576 strncpy(prompt
+ challengelen
,
2577 memchr(prompt
, '\n', challengelen
) ?
2578 "": "\r\nResponse: ",
2579 (sizeof prompt
) - challengelen
);
2580 prompt
[(sizeof prompt
) - 1] = '\0';
2583 if (cfg
.try_tis_auth
&&
2584 (supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2585 !ccard_auth_refused
) {
2586 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2587 logevent("Requested CryptoCard authentication");
2588 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2590 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2591 logevent("CryptoCard authentication declined");
2592 c_write_str("CryptoCard authentication refused.\r\n");
2593 ccard_auth_refused
= 1;
2596 int challengelen
= ((pktin
.body
[0] << 24) |
2597 (pktin
.body
[1] << 16) |
2598 (pktin
.body
[2] << 8) |
2600 logevent("Received CryptoCard challenge");
2601 if (challengelen
> sizeof(prompt
) - 1)
2602 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2603 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2604 strncpy(prompt
+ challengelen
,
2605 memchr(prompt
, '\n', challengelen
) ?
2606 "" : "\r\nResponse: ",
2607 sizeof(prompt
) - challengelen
);
2608 prompt
[sizeof(prompt
) - 1] = '\0';
2611 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2612 sprintf(prompt
, "%.90s@%.90s's password: ",
2613 username
, savedhost
);
2615 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2616 char *comment
= NULL
;
2619 if (flags
& FLAG_VERBOSE
)
2620 c_write_str("Trying public key authentication.\r\n");
2621 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2623 type
= key_type(cfg
.keyfile
);
2624 if (type
!= SSH_KEYTYPE_SSH1
) {
2625 sprintf(msgbuf
, "Key is of wrong type (%s)",
2626 key_type_to_str(type
));
2628 c_write_str(msgbuf
);
2629 c_write_str("\r\n");
2630 tried_publickey
= 1;
2633 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2634 if (flags
& FLAG_VERBOSE
)
2635 c_write_str("No passphrase required.\r\n");
2638 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
2643 * Show password prompt, having first obtained it via a TIS
2644 * or CryptoCard exchange if we're doing TIS or CryptoCard
2648 if (!ssh_get_line(prompt
, password
, sizeof(password
), TRUE
)) {
2650 * get_line failed to get a password (for example
2651 * because one was supplied on the command line
2652 * which has already failed to work). Terminate.
2654 send_packet(SSH1_MSG_DISCONNECT
,
2655 PKT_STR
, "No more passwords available to try",
2657 logevent("Unable to authenticate");
2658 connection_fatal("Unable to authenticate");
2659 ssh_state
= SSH_STATE_CLOSED
;
2663 /* Prompt may have come from server. We've munged it a bit, so
2664 * we know it to be zero-terminated at least once. */
2666 c_write_untrusted(prompt
, strlen(prompt
));
2669 setup_userpass_input(password
, sizeof(password
), 0);
2671 crWaitUntil(!ispkt
);
2672 ret
= process_userpass_input(in
, inlen
);
2676 c_write_str("\r\n");
2680 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2682 * Try public key authentication with the specified
2685 static struct RSAKey pubkey
;
2686 static Bignum challenge
, response
;
2688 static unsigned char buffer
[32];
2690 tried_publickey
= 1;
2691 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
2693 c_write_str("Couldn't load private key from ");
2694 c_write_str(cfg
.keyfile
);
2695 c_write_str(".\r\n");
2696 continue; /* go and try password */
2699 c_write_str("Wrong passphrase.\r\n");
2700 tried_publickey
= 0;
2701 continue; /* try again */
2705 * Send a public key attempt.
2707 send_packet(SSH1_CMSG_AUTH_RSA
,
2708 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
2711 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2712 c_write_str("Server refused our public key.\r\n");
2713 continue; /* go and try password */
2715 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2716 bombout(("Bizarre response to offer of public key"));
2719 ssh1_read_bignum(pktin
.body
, &challenge
);
2720 response
= rsadecrypt(challenge
, &pubkey
);
2721 freebn(pubkey
.private_exponent
); /* burn the evidence */
2723 for (i
= 0; i
< 32; i
++) {
2724 buffer
[i
] = bignum_byte(response
, 31 - i
);
2728 MD5Update(&md5c
, buffer
, 32);
2729 MD5Update(&md5c
, session_id
, 16);
2730 MD5Final(buffer
, &md5c
);
2732 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2733 PKT_DATA
, buffer
, 16, PKT_END
);
2736 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2737 if (flags
& FLAG_VERBOSE
)
2739 ("Failed to authenticate with our public key.\r\n");
2740 continue; /* go and try password */
2741 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2743 ("Bizarre response to RSA authentication response"));
2747 break; /* we're through! */
2749 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2751 * Defence against traffic analysis: we send a
2752 * whole bunch of packets containing strings of
2753 * different lengths. One of these strings is the
2754 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2755 * The others are all random data in
2756 * SSH1_MSG_IGNORE packets. This way a passive
2757 * listener can't tell which is the password, and
2758 * hence can't deduce the password length.
2760 * Anybody with a password length greater than 16
2761 * bytes is going to have enough entropy in their
2762 * password that a listener won't find it _that_
2763 * much help to know how long it is. So what we'll
2766 * - if password length < 16, we send 15 packets
2767 * containing string lengths 1 through 15
2769 * - otherwise, we let N be the nearest multiple
2770 * of 8 below the password length, and send 8
2771 * packets containing string lengths N through
2772 * N+7. This won't obscure the order of
2773 * magnitude of the password length, but it will
2774 * introduce a bit of extra uncertainty.
2776 * A few servers (the old 1.2.18 through 1.2.22)
2777 * can't deal with SSH1_MSG_IGNORE. For these
2778 * servers, we need an alternative defence. We make
2779 * use of the fact that the password is interpreted
2780 * as a C string: so we can append a NUL, then some
2783 * One server (a Cisco one) can deal with neither
2784 * SSH1_MSG_IGNORE _nor_ a padded password string.
2785 * For this server we are left with no defences
2786 * against password length sniffing.
2788 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2790 * The server can deal with SSH1_MSG_IGNORE, so
2791 * we can use the primary defence.
2793 int bottom
, top
, pwlen
, i
;
2796 pwlen
= strlen(password
);
2798 bottom
= 0; /* zero length passwords are OK! :-) */
2801 bottom
= pwlen
& ~7;
2805 assert(pwlen
>= bottom
&& pwlen
<= top
);
2807 randomstr
= smalloc(top
+ 1);
2809 for (i
= bottom
; i
<= top
; i
++) {
2811 defer_packet(pwpkt_type
, PKT_STR
, password
,
2814 for (j
= 0; j
< i
; j
++) {
2816 randomstr
[j
] = random_byte();
2817 } while (randomstr
[j
] == '\0');
2819 randomstr
[i
] = '\0';
2820 defer_packet(SSH1_MSG_IGNORE
,
2821 PKT_STR
, randomstr
, PKT_END
);
2824 logevent("Sending password with camouflage packets");
2825 ssh_pkt_defersend();
2827 else if (!(ssh_remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2829 * The server can't deal with SSH1_MSG_IGNORE
2830 * but can deal with padded passwords, so we
2831 * can use the secondary defence.
2837 len
= strlen(password
);
2838 if (len
< sizeof(string
)) {
2840 strcpy(string
, password
);
2841 len
++; /* cover the zero byte */
2842 while (len
< sizeof(string
)) {
2843 string
[len
++] = (char) random_byte();
2848 logevent("Sending length-padded password");
2849 send_packet(pwpkt_type
, PKT_INT
, len
,
2850 PKT_DATA
, s
, len
, PKT_END
);
2853 * The server has _both_
2854 * BUG_CHOKES_ON_SSH1_IGNORE and
2855 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2856 * therefore nothing we can do.
2859 len
= strlen(password
);
2860 logevent("Sending unpadded password");
2861 send_packet(pwpkt_type
, PKT_INT
, len
,
2862 PKT_DATA
, password
, len
, PKT_END
);
2865 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
2868 logevent("Sent password");
2869 memset(password
, 0, strlen(password
));
2871 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2872 if (flags
& FLAG_VERBOSE
)
2873 c_write_str("Access denied\r\n");
2874 logevent("Authentication refused");
2875 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2876 logevent("Received disconnect request");
2877 ssh_state
= SSH_STATE_CLOSED
;
2879 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2880 bombout(("Strange packet received, type %d", pktin
.type
));
2885 logevent("Authentication successful");
2890 void sshfwd_close(struct ssh_channel
*c
)
2892 if (c
&& !c
->closes
) {
2894 * If the channel's remoteid is -1, we have sent
2895 * CHANNEL_OPEN for this channel, but it hasn't even been
2896 * acknowledged by the server. So we must set a close flag
2897 * on it now, and then when the server acks the channel
2898 * open, we can close it then.
2900 if (((int)c
->remoteid
) != -1) {
2901 if (ssh_version
== 1) {
2902 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2905 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2906 ssh2_pkt_adduint32(c
->remoteid
);
2910 c
->closes
= 1; /* sent MSG_CLOSE */
2911 if (c
->type
== CHAN_X11
) {
2913 logevent("Forwarded X11 connection terminated");
2914 } else if (c
->type
== CHAN_SOCKDATA
||
2915 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2917 logevent("Forwarded port closed");
2922 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2924 if (ssh_version
== 1) {
2925 send_packet(SSH1_MSG_CHANNEL_DATA
,
2926 PKT_INT
, c
->remoteid
,
2927 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2929 * In SSH1 we can return 0 here - implying that forwarded
2930 * connections are never individually throttled - because
2931 * the only circumstance that can cause throttling will be
2932 * the whole SSH connection backing up, in which case
2933 * _everything_ will be throttled as a whole.
2937 ssh2_add_channel_data(c
, buf
, len
);
2938 return ssh2_try_send(c
);
2942 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2944 if (ssh_version
== 1) {
2945 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2946 c
->v
.v1
.throttling
= 0;
2950 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
2954 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
)
2960 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
2963 if (ssh_state
== SSH_STATE_CLOSED
)
2966 if (cfg
.agentfwd
&& agent_exists()) {
2967 logevent("Requesting agent forwarding");
2968 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
2972 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2973 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2974 bombout(("Protocol confusion"));
2976 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2977 logevent("Agent forwarding refused");
2979 logevent("Agent forwarding enabled");
2980 ssh_agentfwd_enabled
= TRUE
;
2984 if (cfg
.x11_forward
) {
2985 char proto
[20], data
[64];
2986 logevent("Requesting X11 forwarding");
2987 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2988 if (ssh1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
2989 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2990 PKT_STR
, proto
, PKT_STR
, data
,
2991 PKT_INT
, 0, PKT_END
);
2993 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2994 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
2999 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3000 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3001 bombout(("Protocol confusion"));
3003 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3004 logevent("X11 forwarding refused");
3006 logevent("X11 forwarding enabled");
3007 ssh_X11_fwd_enabled
= TRUE
;
3015 int sport
,dport
,sserv
,dserv
;
3016 char sports
[256], dports
[256], host
[256];
3020 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3021 /* Add port forwardings. */
3026 while (*e
&& *e
!= '\t')
3032 while (*e
&& *e
!= ':')
3042 dport
= atoi(dports
);
3046 se
= getservbyname(dports
, NULL
);
3048 dport
= ntohs(se
->s_port
);
3051 "Service lookup failed for destination port \"%s\"",
3056 sport
= atoi(sports
);
3060 se
= getservbyname(sports
, NULL
);
3062 sport
= ntohs(se
->s_port
);
3065 "Service lookup failed for source port \"%s\"",
3070 if (sport
&& dport
) {
3072 pfd_addforward(host
, dport
, sport
);
3073 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3074 " %s:%.*s%.*s%d%.*s",
3075 sserv ?
strlen(sports
) : 0, sports
,
3076 sserv
, "(", sport
, sserv
, ")",
3078 dserv ?
strlen(dports
) : 0, dports
,
3079 dserv
, "(", dport
, dserv
, ")");
3082 struct ssh_rportfwd
*pf
;
3083 pf
= smalloc(sizeof(*pf
));
3084 strcpy(pf
->dhost
, host
);
3086 if (add234(ssh_rportfwds
, pf
) != pf
) {
3088 "Duplicate remote port forwarding to %s:%d",
3093 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3094 " forward to %s:%.*s%.*s%d%.*s",
3095 sserv ?
strlen(sports
) : 0, sports
,
3096 sserv
, "(", sport
, sserv
, ")",
3098 dserv ?
strlen(dports
) : 0, dports
,
3099 dserv
, "(", dport
, dserv
, ")");
3101 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST
,
3109 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3110 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3111 bombout(("Protocol confusion"));
3113 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3114 c_write_str("Server refused port forwarding\r\n");
3115 ssh_editing
= ssh_echoing
= 1;
3117 logevent("Remote port forwarding enabled");
3125 send_packet(SSH1_CMSG_REQUEST_PTY
,
3126 PKT_STR
, cfg
.termtype
,
3127 PKT_INT
, rows
, PKT_INT
, cols
,
3128 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3129 ssh_state
= SSH_STATE_INTERMED
;
3133 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3134 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3135 bombout(("Protocol confusion"));
3137 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3138 c_write_str("Server refused to allocate pty\r\n");
3139 ssh_editing
= ssh_echoing
= 1;
3141 logevent("Allocated pty");
3143 ssh_editing
= ssh_echoing
= 1;
3146 if (cfg
.compression
) {
3147 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3151 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3152 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3153 bombout(("Protocol confusion"));
3155 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3156 c_write_str("Server refused to compress\r\n");
3158 logevent("Started compression");
3159 ssh1_compressing
= TRUE
;
3160 zlib_compress_init();
3161 zlib_decompress_init();
3165 * Start the shell or command.
3167 * Special case: if the first-choice command is an SSH2
3168 * subsystem (hence not usable here) and the second choice
3169 * exists, we fall straight back to that.
3172 char *cmd
= cfg
.remote_cmd_ptr
;
3174 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3175 cmd
= cfg
.remote_cmd_ptr2
;
3176 ssh_fallback_cmd
= TRUE
;
3179 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3181 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3182 logevent("Started session");
3185 ssh_state
= SSH_STATE_SESSION
;
3189 ssh_special(TS_EOF
);
3191 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
3193 ssh_channels
= newtree234(ssh_channelcmp
);
3197 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3198 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3199 long len
= GET_32BIT(pktin
.body
);
3201 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3202 pktin
.body
+ 4, len
);
3203 if (!ssh1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3204 ssh1_stdout_throttling
= 1;
3207 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
3208 ssh_state
= SSH_STATE_CLOSED
;
3209 logevent("Received disconnect request");
3211 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3212 /* Remote side is trying to open a channel to talk to our
3213 * X-Server. Give them back a local channel number. */
3214 struct ssh_channel
*c
;
3216 logevent("Received X11 connect request");
3217 /* Refuse if X11 forwarding is disabled. */
3218 if (!ssh_X11_fwd_enabled
) {
3219 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3220 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3221 logevent("Rejected X11 connect request");
3223 c
= smalloc(sizeof(struct ssh_channel
));
3225 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3226 logevent("opening X11 forward connection failed");
3228 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3229 PKT_INT
, GET_32BIT(pktin
.body
),
3233 ("opening X11 forward connection succeeded");
3234 c
->remoteid
= GET_32BIT(pktin
.body
);
3235 c
->localid
= alloc_channel_id();
3237 c
->v
.v1
.throttling
= 0;
3238 c
->type
= CHAN_X11
; /* identify channel type */
3239 add234(ssh_channels
, c
);
3240 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3241 PKT_INT
, c
->remoteid
, PKT_INT
,
3242 c
->localid
, PKT_END
);
3243 logevent("Opened X11 forward channel");
3246 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3247 /* Remote side is trying to open a channel to talk to our
3248 * agent. Give them back a local channel number. */
3249 struct ssh_channel
*c
;
3251 /* Refuse if agent forwarding is disabled. */
3252 if (!ssh_agentfwd_enabled
) {
3253 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3254 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3256 c
= smalloc(sizeof(struct ssh_channel
));
3257 c
->remoteid
= GET_32BIT(pktin
.body
);
3258 c
->localid
= alloc_channel_id();
3260 c
->v
.v1
.throttling
= 0;
3261 c
->type
= CHAN_AGENT
; /* identify channel type */
3262 c
->u
.a
.lensofar
= 0;
3263 add234(ssh_channels
, c
);
3264 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3265 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3268 } else if (pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3269 /* Remote side is trying to open a channel to talk to a
3270 * forwarded port. Give them back a local channel number. */
3271 struct ssh_channel
*c
;
3272 struct ssh_rportfwd pf
;
3274 char host
[256], buf
[1024];
3276 c
= smalloc(sizeof(struct ssh_channel
));
3278 hostsize
= GET_32BIT(pktin
.body
+4);
3279 for(h
= host
, p
= pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3280 if (h
+1 < host
+sizeof(host
))
3285 port
= GET_32BIT(p
);
3287 strcpy(pf
.dhost
, host
);
3290 if (find234(ssh_rportfwds
, &pf
, NULL
) == NULL
) {
3291 sprintf(buf
, "Rejected remote port open request for %s:%d",
3294 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3295 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3297 sprintf(buf
, "Received remote port open request for %s:%d",
3300 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3303 sprintf(buf
, "Port open failed: %s", e
);
3306 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3307 PKT_INT
, GET_32BIT(pktin
.body
),
3310 c
->remoteid
= GET_32BIT(pktin
.body
);
3311 c
->localid
= alloc_channel_id();
3313 c
->v
.v1
.throttling
= 0;
3314 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3315 add234(ssh_channels
, c
);
3316 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3317 PKT_INT
, c
->remoteid
, PKT_INT
,
3318 c
->localid
, PKT_END
);
3319 logevent("Forwarded port opened successfully");
3323 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3324 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3325 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3326 struct ssh_channel
*c
;
3328 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3329 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3330 c
->remoteid
= localid
;
3331 c
->type
= CHAN_SOCKDATA
;
3332 c
->v
.v1
.throttling
= 0;
3333 pfd_confirm(c
->u
.pfd
.s
);
3336 if (c
&& c
->closes
) {
3338 * We have a pending close on this channel,
3339 * which we decided on before the server acked
3340 * the channel open. So now we know the
3341 * remoteid, we can close it again.
3343 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3347 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3348 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3349 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3350 struct ssh_channel
*c
;
3352 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3353 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3354 logevent("Forwarded connection refused by server");
3355 pfd_close(c
->u
.pfd
.s
);
3356 del234(ssh_channels
, c
);
3360 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3361 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3362 /* Remote side closes a channel. */
3363 unsigned i
= GET_32BIT(pktin
.body
);
3364 struct ssh_channel
*c
;
3365 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3366 if (c
&& ((int)c
->remoteid
) != -1) {
3369 (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3371 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3372 logevent("Forwarded X11 connection terminated");
3373 assert(c
->u
.x11
.s
!= NULL
);
3374 x11_close(c
->u
.x11
.s
);
3377 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3378 logevent("Forwarded port closed");
3379 assert(c
->u
.pfd
.s
!= NULL
);
3380 pfd_close(c
->u
.pfd
.s
);
3384 c
->closes
|= (closetype
<< 2); /* seen this message */
3385 if (!(c
->closes
& closetype
)) {
3386 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
,
3388 c
->closes
|= closetype
; /* sent it too */
3391 if (c
->closes
== 15) {
3392 del234(ssh_channels
, c
);
3396 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3397 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3398 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3401 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3402 /* Data sent down one of our channels. */
3403 int i
= GET_32BIT(pktin
.body
);
3404 int len
= GET_32BIT(pktin
.body
+ 4);
3405 unsigned char *p
= pktin
.body
+ 8;
3406 struct ssh_channel
*c
;
3407 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3412 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3415 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3418 /* Data for an agent message. Buffer it. */
3420 if (c
->u
.a
.lensofar
< 4) {
3421 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3422 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3426 c
->u
.a
.lensofar
+= l
;
3428 if (c
->u
.a
.lensofar
== 4) {
3430 4 + GET_32BIT(c
->u
.a
.msglen
);
3431 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3432 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3434 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3436 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3438 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3442 c
->u
.a
.lensofar
+= l
;
3444 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3445 void *reply
, *sentreply
;
3447 agent_query(c
->u
.a
.message
,
3448 c
->u
.a
.totallen
, &reply
,
3453 /* Fake SSH_AGENT_FAILURE. */
3454 sentreply
= "\0\0\0\1\5";
3457 send_packet(SSH1_MSG_CHANNEL_DATA
,
3458 PKT_INT
, c
->remoteid
,
3460 PKT_DATA
, sentreply
, replylen
,
3464 sfree(c
->u
.a
.message
);
3465 c
->u
.a
.lensofar
= 0;
3468 bufsize
= 0; /* agent channels never back up */
3471 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3472 c
->v
.v1
.throttling
= 1;
3476 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
3477 /* may be from EXEC_SHELL on some servers */
3478 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3479 /* may be from EXEC_SHELL on some servers
3480 * if no pty is available or in other odd cases. Ignore */
3481 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3483 ssh_exitcode
= GET_32BIT(pktin
.body
);
3484 sprintf(buf
, "Server sent command exit status %d",
3487 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3489 * In case `helpful' firewalls or proxies tack
3490 * extra human-readable text on the end of the
3491 * session which we might mistake for another
3492 * encrypted packet, we close the session once
3493 * we've sent EXIT_CONFIRMATION.
3495 ssh_state
= SSH_STATE_CLOSED
;
3498 bombout(("Strange packet received: type %d", pktin
.type
));
3503 int len
= min(inlen
, 512);
3504 send_packet(SSH1_CMSG_STDIN_DATA
,
3505 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3516 * Utility routine for decoding comma-separated strings in KEXINIT.
3518 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3520 int needlen
= strlen(needle
);
3523 * Is it at the start of the string?
3525 if (haylen
>= needlen
&& /* haystack is long enough */
3526 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3527 (haylen
== needlen
|| haystack
[needlen
] == ',')
3528 /* either , or EOS follows */
3532 * If not, search for the next comma and resume after that.
3533 * If no comma found, terminate.
3535 while (haylen
> 0 && *haystack
!= ',')
3536 haylen
--, haystack
++;
3539 haylen
--, haystack
++; /* skip over comma itself */
3544 * SSH2 key creation method.
3546 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
,
3550 /* First 20 bytes. */
3552 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3554 SHA_Bytes(&s
, H
, 20);
3555 SHA_Bytes(&s
, &chr
, 1);
3556 SHA_Bytes(&s
, sessid
, 20);
3557 SHA_Final(&s
, keyspace
);
3558 /* Next 20 bytes. */
3560 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3562 SHA_Bytes(&s
, H
, 20);
3563 SHA_Bytes(&s
, keyspace
, 20);
3564 SHA_Final(&s
, keyspace
+ 20);
3568 * Handle the SSH2 transport layer.
3570 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
3572 static int i
, j
, len
, nbits
, pbits
, warn
;
3574 static Bignum p
, g
, e
, f
, K
;
3575 static int kex_init_value
, kex_reply_value
;
3576 static const struct ssh_mac
**maclist
;
3578 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
3579 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
3580 static const struct ssh_mac
*csmac_tobe
= NULL
;
3581 static const struct ssh_mac
*scmac_tobe
= NULL
;
3582 static const struct ssh_compress
*cscomp_tobe
= NULL
;
3583 static const struct ssh_compress
*sccomp_tobe
= NULL
;
3584 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3585 static int hostkeylen
, siglen
;
3586 static void *hkey
; /* actual host key */
3587 static unsigned char exchange_hash
[20];
3588 static unsigned char keyspace
[40];
3589 static int n_preferred_ciphers
;
3590 static const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3591 static const struct ssh_compress
*preferred_comp
;
3592 static int cipherstr_started
;
3593 static int first_kex
;
3600 * Set up the preferred ciphers. (NULL => warn below here)
3602 n_preferred_ciphers
= 0;
3603 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3604 switch (cfg
.ssh_cipherlist
[i
]) {
3605 case CIPHER_BLOWFISH
:
3606 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_blowfish
;
3607 n_preferred_ciphers
++;
3610 if (cfg
.ssh2_des_cbc
) {
3611 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_des
;
3612 n_preferred_ciphers
++;
3616 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_3des
;
3617 n_preferred_ciphers
++;
3620 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_aes
;
3621 n_preferred_ciphers
++;
3624 /* Flag for later. Don't bother if it's the last in
3626 if (i
< CIPHER_MAX
- 1) {
3627 preferred_ciphers
[n_preferred_ciphers
] = NULL
;
3628 n_preferred_ciphers
++;
3635 * Set up preferred compression.
3637 if (cfg
.compression
)
3638 preferred_comp
= &ssh_zlib
;
3640 preferred_comp
= &ssh_comp_none
;
3643 * Be prepared to work around the buggy MAC problem.
3645 if (ssh_remote_bugs
& BUG_SSH2_HMAC
)
3646 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
3648 maclist
= macs
, nmacs
= lenof(macs
);
3652 * Construct and send our key exchange packet.
3654 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
3655 for (i
= 0; i
< 16; i
++)
3656 ssh2_pkt_addbyte((unsigned char) random_byte());
3657 /* List key exchange algorithms. */
3658 ssh2_pkt_addstring_start();
3659 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3660 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3661 (ssh_remote_bugs
& BUG_SSH2_DH_GEX
))
3663 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
3664 if (i
< lenof(kex_algs
) - 1)
3665 ssh2_pkt_addstring_str(",");
3667 /* List server host key algorithms. */
3668 ssh2_pkt_addstring_start();
3669 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3670 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
3671 if (i
< lenof(hostkey_algs
) - 1)
3672 ssh2_pkt_addstring_str(",");
3674 /* List client->server encryption algorithms. */
3675 ssh2_pkt_addstring_start();
3676 cipherstr_started
= 0;
3677 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3678 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3679 if (!c
) continue; /* warning flag */
3680 for (j
= 0; j
< c
->nciphers
; j
++) {
3681 if (cipherstr_started
)
3682 ssh2_pkt_addstring_str(",");
3683 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3684 cipherstr_started
= 1;
3687 /* List server->client encryption algorithms. */
3688 ssh2_pkt_addstring_start();
3689 cipherstr_started
= 0;
3690 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3691 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3692 if (!c
) continue; /* warning flag */
3693 for (j
= 0; j
< c
->nciphers
; j
++) {
3694 if (cipherstr_started
)
3695 ssh2_pkt_addstring_str(",");
3696 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3697 cipherstr_started
= 1;
3700 /* List client->server MAC algorithms. */
3701 ssh2_pkt_addstring_start();
3702 for (i
= 0; i
< nmacs
; i
++) {
3703 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3705 ssh2_pkt_addstring_str(",");
3707 /* List server->client MAC algorithms. */
3708 ssh2_pkt_addstring_start();
3709 for (i
= 0; i
< nmacs
; i
++) {
3710 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3712 ssh2_pkt_addstring_str(",");
3714 /* List client->server compression algorithms. */
3715 ssh2_pkt_addstring_start();
3716 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3717 const struct ssh_compress
*c
=
3718 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3719 ssh2_pkt_addstring_str(c
->name
);
3720 if (i
< lenof(compressions
))
3721 ssh2_pkt_addstring_str(",");
3723 /* List server->client compression algorithms. */
3724 ssh2_pkt_addstring_start();
3725 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3726 const struct ssh_compress
*c
=
3727 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3728 ssh2_pkt_addstring_str(c
->name
);
3729 if (i
< lenof(compressions
))
3730 ssh2_pkt_addstring_str(",");
3732 /* List client->server languages. Empty list. */
3733 ssh2_pkt_addstring_start();
3734 /* List server->client languages. Empty list. */
3735 ssh2_pkt_addstring_start();
3736 /* First KEX packet does _not_ follow, because we're not that brave. */
3737 ssh2_pkt_addbool(FALSE
);
3739 ssh2_pkt_adduint32(0);
3741 exhash
= exhashbase
;
3742 sha_string(&exhash
, pktout
.data
+ 5, pktout
.length
- 5);
3748 sha_string(&exhash
, pktin
.data
+ 5, pktin
.length
- 5);
3751 * Now examine the other side's KEXINIT to see what we're up
3754 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
3755 bombout(("expected key exchange packet from server"));
3760 cscipher_tobe
= NULL
;
3761 sccipher_tobe
= NULL
;
3766 pktin
.savedpos
+= 16; /* skip garbage cookie */
3767 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
3768 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3769 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3770 (ssh_remote_bugs
& BUG_SSH2_DH_GEX
))
3772 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3777 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
3778 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3779 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3780 hostkey
= hostkey_algs
[i
];
3784 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
3786 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3787 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3791 for (j
= 0; j
< c
->nciphers
; j
++) {
3792 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3793 cscipher_tobe
= c
->list
[j
];
3798 if (cscipher_tobe
) {
3800 askcipher(cscipher_tobe
->name
, 1);
3804 if (!cscipher_tobe
) {
3805 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3809 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
3811 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3812 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3816 for (j
= 0; j
< c
->nciphers
; j
++) {
3817 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3818 sccipher_tobe
= c
->list
[j
];
3823 if (sccipher_tobe
) {
3825 askcipher(sccipher_tobe
->name
, 2);
3829 if (!sccipher_tobe
) {
3830 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3834 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
3835 for (i
= 0; i
< nmacs
; i
++) {
3836 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3837 csmac_tobe
= maclist
[i
];
3841 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
3842 for (i
= 0; i
< nmacs
; i
++) {
3843 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3844 scmac_tobe
= maclist
[i
];
3848 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
3849 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3850 const struct ssh_compress
*c
=
3851 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3852 if (in_commasep_string(c
->name
, str
, len
)) {
3857 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
3858 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3859 const struct ssh_compress
*c
=
3860 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3861 if (in_commasep_string(c
->name
, str
, len
)) {
3868 * Work out the number of bits of key we will need from the key
3869 * exchange. We start with the maximum key length of either
3875 csbits
= cscipher_tobe
->keylen
;
3876 scbits
= sccipher_tobe
->keylen
;
3877 nbits
= (csbits
> scbits ? csbits
: scbits
);
3879 /* The keys only have 160-bit entropy, since they're based on
3880 * a SHA-1 hash. So cap the key size at 160 bits. */
3885 * If we're doing Diffie-Hellman group exchange, start by
3886 * requesting a group.
3888 if (kex
== &ssh_diffiehellman_gex
) {
3889 logevent("Doing Diffie-Hellman group exchange");
3890 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3892 * Work out how big a DH group we will need to allow that
3895 pbits
= 512 << ((nbits
- 1) / 64);
3896 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
3897 ssh2_pkt_adduint32(pbits
);
3901 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3902 bombout(("expected key exchange group packet from server"));
3905 p
= ssh2_pkt_getmp();
3906 g
= ssh2_pkt_getmp();
3907 dh_setup_group(p
, g
);
3908 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3909 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3911 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3913 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3914 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3917 logevent("Doing Diffie-Hellman key exchange");
3919 * Now generate and send e for Diffie-Hellman.
3921 e
= dh_create_e(nbits
* 2);
3922 ssh2_pkt_init(kex_init_value
);
3927 if (pktin
.type
!= kex_reply_value
) {
3928 bombout(("expected key exchange reply packet from server"));
3931 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
3932 f
= ssh2_pkt_getmp();
3933 ssh2_pkt_getstring(&sigdata
, &siglen
);
3937 sha_string(&exhash
, hostkeydata
, hostkeylen
);
3938 if (kex
== &ssh_diffiehellman_gex
) {
3939 sha_uint32(&exhash
, pbits
);
3940 sha_mpint(&exhash
, p
);
3941 sha_mpint(&exhash
, g
);
3943 sha_mpint(&exhash
, e
);
3944 sha_mpint(&exhash
, f
);
3945 sha_mpint(&exhash
, K
);
3946 SHA_Final(&exhash
, exchange_hash
);
3951 debug(("Exchange hash is:\n"));
3952 dmemdump(exchange_hash
, 20);
3955 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
3957 !hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
3958 bombout(("Server's host key did not match the signature supplied"));
3963 * Authenticate remote host: verify host key. (We've already
3964 * checked the signature of the exchange hash.)
3966 keystr
= hostkey
->fmtkey(hkey
);
3967 fingerprint
= hostkey
->fingerprint(hkey
);
3968 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
3969 keystr
, fingerprint
);
3970 if (first_kex
) { /* don't bother logging this in rekeys */
3971 logevent("Host key fingerprint is:");
3972 logevent(fingerprint
);
3976 hostkey
->freekey(hkey
);
3979 * Send SSH2_MSG_NEWKEYS.
3981 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
3985 * Expect SSH2_MSG_NEWKEYS from server.
3988 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
3989 bombout(("expected new-keys packet from server"));
3994 * Create and initialise session keys.
3996 cscipher
= cscipher_tobe
;
3997 sccipher
= sccipher_tobe
;
4000 cscomp
= cscomp_tobe
;
4001 sccomp
= sccomp_tobe
;
4002 cscomp
->compress_init();
4003 sccomp
->decompress_init();
4005 * Set IVs after keys. Here we use the exchange hash from the
4006 * _first_ key exchange.
4009 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
4010 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
4011 cscipher
->setcskey(keyspace
);
4012 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
4013 sccipher
->setsckey(keyspace
);
4014 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
4015 cscipher
->setcsiv(keyspace
);
4016 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
4017 sccipher
->setsciv(keyspace
);
4018 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
4019 csmac
->setcskey(keyspace
);
4020 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
4021 scmac
->setsckey(keyspace
);
4024 * If this is the first key exchange phase, we must pass the
4025 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4026 * wants to see it but because it will need time to initialise
4027 * itself before it sees an actual packet. In subsequent key
4028 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4029 * it would only confuse the layer above.
4037 * Now we're encrypting. Begin returning 1 to the protocol main
4038 * function so that other things can run on top of the
4039 * transport. If we ever see a KEXINIT, we must go back to the
4042 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
4045 logevent("Server initiated key re-exchange");
4046 goto begin_key_exchange
;
4052 * Add data to an SSH2 channel output buffer.
4054 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4057 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4061 * Attempt to send data on an SSH2 channel.
4063 static int ssh2_try_send(struct ssh_channel
*c
)
4065 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4068 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4069 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4070 len
= c
->v
.v2
.remwindow
;
4071 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4072 len
= c
->v
.v2
.remmaxpkt
;
4073 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4074 ssh2_pkt_adduint32(c
->remoteid
);
4075 ssh2_pkt_addstring_start();
4076 ssh2_pkt_addstring_data(data
, len
);
4078 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4079 c
->v
.v2
.remwindow
-= len
;
4083 * After having sent as much data as we can, return the amount
4086 return bufchain_size(&c
->v
.v2
.outbuffer
);
4090 * Potentially enlarge the window on an SSH2 channel.
4092 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4095 * Never send WINDOW_ADJUST for a channel that the remote side
4096 * already thinks it's closed; there's no point, since it won't
4097 * be sending any more data anyway.
4102 if (newwin
> c
->v
.v2
.locwindow
) {
4103 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4104 ssh2_pkt_adduint32(c
->remoteid
);
4105 ssh2_pkt_adduint32(newwin
- c
->v
.v2
.locwindow
);
4107 c
->v
.v2
.locwindow
= newwin
;
4112 * Handle the SSH2 userauth and connection layers.
4114 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
4117 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4119 AUTH_KEYBOARD_INTERACTIVE
4123 AUTH_TYPE_PUBLICKEY
,
4124 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4125 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4127 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4128 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4130 static int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4131 static int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4132 static int kbd_inter_running
;
4133 static int we_are_in
;
4134 static int num_prompts
, curr_prompt
, echo
;
4135 static char username
[100];
4136 static int got_username
;
4137 static char pwprompt
[200];
4138 static char password
[100];
4139 static void *publickey_blob
;
4140 static int publickey_bloblen
;
4145 * Request userauth protocol, and await a response to it.
4147 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
4148 ssh2_pkt_addstring("ssh-userauth");
4150 crWaitUntilV(ispkt
);
4151 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4152 bombout(("Server refused user authentication protocol"));
4157 * We repeat this whole loop, including the username prompt,
4158 * until we manage a successful authentication. If the user
4159 * types the wrong _password_, they are sent back to the
4160 * beginning to try another username. (If they specify a
4161 * username in the config, they are never asked, even if they
4162 * do give a wrong password.)
4164 * I think this best serves the needs of
4166 * - the people who have no configuration, no keys, and just
4167 * want to try repeated (username,password) pairs until they
4168 * type both correctly
4170 * - people who have keys and configuration but occasionally
4171 * need to fall back to passwords
4173 * - people with a key held in Pageant, who might not have
4174 * logged in to a particular machine before; so they want to
4175 * type a username, and then _either_ their key will be
4176 * accepted, _or_ they will type a password. If they mistype
4177 * the username they will want to be able to get back and
4181 got_username
= FALSE
;
4186 if (got_username
&& !cfg
.change_username
) {
4188 * We got a username last time round this loop, and
4189 * with change_username turned off we don't try to get
4192 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4193 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4194 if (!ssh_get_line("login as: ",
4195 username
, sizeof(username
), FALSE
)) {
4197 * get_line failed to get a username.
4200 logevent("No username provided. Abandoning session.");
4201 ssh_state
= SSH_STATE_CLOSED
;
4206 c_write_str("login as: ");
4208 setup_userpass_input(username
, sizeof(username
), 1);
4210 crWaitUntilV(!ispkt
);
4211 ret
= process_userpass_input(in
, inlen
);
4216 c_write_str("\r\n");
4217 username
[strcspn(username
, "\n\r")] = '\0';
4220 strncpy(username
, cfg
.username
, sizeof(username
));
4221 username
[sizeof(username
)-1] = '\0';
4222 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4223 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
4227 got_username
= TRUE
;
4230 * Send an authentication request using method "none": (a)
4231 * just in case it succeeds, and (b) so that we know what
4232 * authentication methods we can usefully try next.
4234 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4236 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4237 ssh2_pkt_addstring(username
);
4238 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4239 ssh2_pkt_addstring("none"); /* method */
4241 type
= AUTH_TYPE_NONE
;
4245 tried_pubkey_config
= FALSE
;
4246 tried_agent
= FALSE
;
4247 tried_keyb_inter
= FALSE
;
4248 kbd_inter_running
= FALSE
;
4249 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4252 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4253 keytype
= key_type(cfg
.keyfile
);
4254 if (keytype
== SSH_KEYTYPE_SSH2
)
4255 publickey_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4256 &publickey_bloblen
);
4259 logeventf("Unable to use this key file (%s)",
4260 key_type_to_str(keytype
));
4261 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4262 cfg
.keyfile
, key_type_to_str(keytype
));
4263 c_write_str(msgbuf
);
4264 publickey_blob
= NULL
;
4267 publickey_blob
= NULL
;
4271 * Wait for the result of the last authentication request.
4274 crWaitUntilV(ispkt
);
4275 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4279 * Don't show the banner if we're operating in
4280 * non-verbose non-interactive mode. (It's probably
4281 * a script, which means nobody will read the
4282 * banner _anyway_, and moreover the printing of
4283 * the banner will screw up processing on the
4284 * output of (say) plink.)
4286 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4287 ssh2_pkt_getstring(&banner
, &size
);
4289 c_write_untrusted(banner
, size
);
4291 crWaitUntilV(ispkt
);
4293 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4294 logevent("Access granted");
4299 if (kbd_inter_running
&&
4300 pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4302 * This is either a further set-of-prompts packet
4303 * in keyboard-interactive authentication, or it's
4304 * the same one and we came back here with `gotit'
4305 * set. In the former case, we must reset the
4306 * curr_prompt variable.
4310 } else if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4311 bombout(("Strange packet received during authentication: type %d",
4319 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4320 * we can look at the string in it and know what we can
4321 * helpfully try next.
4323 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4326 ssh2_pkt_getstring(&methods
, &methlen
);
4327 kbd_inter_running
= FALSE
;
4328 if (!ssh2_pkt_getbool()) {
4330 * We have received an unequivocal Access
4331 * Denied. This can translate to a variety of
4334 * - if we'd just tried "none" authentication,
4335 * it's not worth printing anything at all
4337 * - if we'd just tried a public key _offer_,
4338 * the message should be "Server refused our
4339 * key" (or no message at all if the key
4340 * came from Pageant)
4342 * - if we'd just tried anything else, the
4343 * message really should be "Access denied".
4345 * Additionally, if we'd just tried password
4346 * authentication, we should break out of this
4347 * whole loop so as to go back to the username
4350 if (type
== AUTH_TYPE_NONE
) {
4352 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4353 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4354 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4355 c_write_str("Server refused our key\r\n");
4356 logevent("Server refused public key");
4357 } else if (type
== AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4358 /* server declined keyboard-interactive; ignore */
4360 c_write_str("Access denied\r\n");
4361 logevent("Access denied");
4362 if (type
== AUTH_TYPE_PASSWORD
) {
4368 c_write_str("Further authentication required\r\n");
4369 logevent("Further authentication required");
4373 in_commasep_string("publickey", methods
, methlen
);
4375 in_commasep_string("password", methods
, methlen
);
4376 can_keyb_inter
= cfg
.try_ki_auth
&&
4377 in_commasep_string("keyboard-interactive", methods
, methlen
);
4381 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4384 * Most password/passphrase prompts will be
4385 * non-echoing, so we set this to 0 by default.
4386 * Exception is that some keyboard-interactive prompts
4387 * can be echoing, in which case we'll set this to 1.
4391 if (!method
&& can_pubkey
&& agent_exists() && !tried_agent
) {
4393 * Attempt public-key authentication using Pageant.
4395 static unsigned char request
[5], *response
, *p
;
4396 static int responselen
;
4397 static int i
, nkeys
;
4398 static int authed
= FALSE
;
4401 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4402 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4406 logevent("Pageant is running. Requesting keys.");
4408 /* Request the keys held by the agent. */
4409 PUT_32BIT(request
, 1);
4410 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4411 agent_query(request
, 5, &r
, &responselen
);
4412 response
= (unsigned char *) r
;
4413 if (response
&& responselen
>= 5 &&
4414 response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4416 nkeys
= GET_32BIT(p
);
4420 sprintf(buf
, "Pageant has %d SSH2 keys", nkeys
);
4423 for (i
= 0; i
< nkeys
; i
++) {
4424 static char *pkblob
, *alg
, *commentp
;
4425 static int pklen
, alglen
, commentlen
;
4426 static int siglen
, retlen
, len
;
4427 static char *q
, *agentreq
, *ret
;
4432 sprintf(buf
, "Trying Pageant key #%d", i
);
4435 pklen
= GET_32BIT(p
);
4437 if (publickey_blob
&&
4438 pklen
== publickey_bloblen
&&
4439 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
4440 logevent("This key matches configured key file");
4441 tried_pubkey_config
= 1;
4445 alglen
= GET_32BIT(pkblob
);
4447 commentlen
= GET_32BIT(p
);
4451 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4452 ssh2_pkt_addstring(username
);
4453 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4454 ssh2_pkt_addstring("publickey"); /* method */
4455 ssh2_pkt_addbool(FALSE
); /* no signature included */
4456 ssh2_pkt_addstring_start();
4457 ssh2_pkt_addstring_data(alg
, alglen
);
4458 ssh2_pkt_addstring_start();
4459 ssh2_pkt_addstring_data(pkblob
, pklen
);
4462 crWaitUntilV(ispkt
);
4463 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4464 logevent("Key refused");
4468 if (flags
& FLAG_VERBOSE
) {
4470 ("Authenticating with public key \"");
4471 c_write(commentp
, commentlen
);
4472 c_write_str("\" from agent\r\n");
4476 * Server is willing to accept the key.
4477 * Construct a SIGN_REQUEST.
4479 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4480 ssh2_pkt_addstring(username
);
4481 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4482 ssh2_pkt_addstring("publickey"); /* method */
4483 ssh2_pkt_addbool(TRUE
);
4484 ssh2_pkt_addstring_start();
4485 ssh2_pkt_addstring_data(alg
, alglen
);
4486 ssh2_pkt_addstring_start();
4487 ssh2_pkt_addstring_data(pkblob
, pklen
);
4489 siglen
= pktout
.length
- 5 + 4 + 20;
4490 len
= 1; /* message type */
4491 len
+= 4 + pklen
; /* key blob */
4492 len
+= 4 + siglen
; /* data to sign */
4493 len
+= 4; /* flags */
4494 agentreq
= smalloc(4 + len
);
4495 PUT_32BIT(agentreq
, len
);
4497 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4498 PUT_32BIT(q
, pklen
);
4500 memcpy(q
, pkblob
, pklen
);
4502 PUT_32BIT(q
, siglen
);
4504 /* Now the data to be signed... */
4507 memcpy(q
, ssh2_session_id
, 20);
4509 memcpy(q
, pktout
.data
+ 5, pktout
.length
- 5);
4510 q
+= pktout
.length
- 5;
4511 /* And finally the (zero) flags word. */
4513 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
4517 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4518 logevent("Sending Pageant's response");
4519 ssh2_add_sigblob(pkblob
, pklen
,
4520 ret
+ 9, GET_32BIT(ret
+ 5));
4526 ("Pageant failed to answer challenge");
4536 if (!method
&& can_pubkey
&& publickey_blob
4537 && !tried_pubkey_config
) {
4538 unsigned char *pub_blob
;
4539 char *algorithm
, *comment
;
4542 tried_pubkey_config
= TRUE
;
4544 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4545 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4548 * Try the public key supplied in the configuration.
4550 * First, offer the public blob to see if the server is
4551 * willing to accept it.
4553 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4556 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4557 ssh2_pkt_addstring(username
);
4558 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4559 ssh2_pkt_addstring("publickey"); /* method */
4560 ssh2_pkt_addbool(FALSE
); /* no signature included */
4561 ssh2_pkt_addstring(algorithm
);
4562 ssh2_pkt_addstring_start();
4563 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
4565 logevent("Offered public key"); /* FIXME */
4567 crWaitUntilV(ispkt
);
4568 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4570 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4571 continue; /* key refused; give up on it */
4574 logevent("Offer of public key accepted");
4576 * Actually attempt a serious authentication using
4579 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4581 "Passphrase for key \"%.100s\": ",
4587 c_write_str("Authenticating with public key \"");
4588 c_write_str(comment
);
4589 c_write_str("\"\r\n");
4590 method
= AUTH_PUBLICKEY_FILE
;
4594 if (!method
&& can_keyb_inter
&& !tried_keyb_inter
) {
4595 method
= AUTH_KEYBOARD_INTERACTIVE
;
4596 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4597 tried_keyb_inter
= TRUE
;
4599 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4600 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4602 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4603 ssh2_pkt_addstring(username
);
4604 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4605 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4606 ssh2_pkt_addstring(""); /* lang */
4607 ssh2_pkt_addstring("");
4610 crWaitUntilV(ispkt
);
4611 if (pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4612 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4614 logevent("Keyboard-interactive authentication refused");
4615 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4619 kbd_inter_running
= TRUE
;
4623 if (kbd_inter_running
) {
4624 method
= AUTH_KEYBOARD_INTERACTIVE
;
4625 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4626 tried_keyb_inter
= TRUE
;
4628 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4629 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4631 if (curr_prompt
== 0) {
4633 * We've got a fresh USERAUTH_INFO_REQUEST.
4634 * Display header data, and start going through
4637 char *name
, *inst
, *lang
;
4638 int name_len
, inst_len
, lang_len
;
4640 ssh2_pkt_getstring(&name
, &name_len
);
4641 ssh2_pkt_getstring(&inst
, &inst_len
);
4642 ssh2_pkt_getstring(&lang
, &lang_len
);
4644 c_write_untrusted(name
, name_len
);
4645 c_write_str("\r\n");
4648 c_write_untrusted(inst
, inst_len
);
4649 c_write_str("\r\n");
4651 num_prompts
= ssh2_pkt_getuint32();
4655 * If there are prompts remaining in the packet,
4656 * display one and get a response.
4658 if (curr_prompt
< num_prompts
) {
4662 ssh2_pkt_getstring(&prompt
, &prompt_len
);
4663 if (prompt_len
> 0) {
4664 strncpy(pwprompt
, prompt
, sizeof(pwprompt
));
4665 pwprompt
[prompt_len
< sizeof(pwprompt
) ?
4666 prompt_len
: sizeof(pwprompt
)-1] = '\0';
4669 "<server failed to send prompt>: ");
4671 echo
= ssh2_pkt_getbool();
4677 if (!method
&& can_passwd
) {
4678 method
= AUTH_PASSWORD
;
4679 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4680 ssh_pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4681 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
,
4688 if (!ssh_get_line(pwprompt
, password
,
4689 sizeof(password
), TRUE
)) {
4691 * get_line failed to get a password (for
4692 * example because one was supplied on the
4693 * command line which has already failed to
4696 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4697 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4699 ("No more passwords available to try");
4700 ssh2_pkt_addstring("en"); /* language tag */
4702 logevent("Unable to authenticate");
4703 connection_fatal("Unable to authenticate");
4704 ssh_state
= SSH_STATE_CLOSED
;
4709 c_write_untrusted(pwprompt
, strlen(pwprompt
));
4712 setup_userpass_input(password
, sizeof(password
), echo
);
4714 crWaitUntilV(!ispkt
);
4715 ret
= process_userpass_input(in
, inlen
);
4719 c_write_str("\r\n");
4723 if (method
== AUTH_PUBLICKEY_FILE
) {
4725 * We have our passphrase. Now try the actual authentication.
4727 struct ssh2_userkey
*key
;
4729 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
4730 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4731 if (key
== SSH2_WRONG_PASSPHRASE
) {
4732 c_write_str("Wrong passphrase\r\n");
4733 tried_pubkey_config
= FALSE
;
4735 c_write_str("Unable to load private key\r\n");
4736 tried_pubkey_config
= TRUE
;
4738 /* Send a spurious AUTH_NONE to return to the top. */
4739 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4740 ssh2_pkt_addstring(username
);
4741 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4742 ssh2_pkt_addstring("none"); /* method */
4744 type
= AUTH_TYPE_NONE
;
4746 unsigned char *pkblob
, *sigblob
, *sigdata
;
4747 int pkblob_len
, sigblob_len
, sigdata_len
;
4750 * We have loaded the private key and the server
4751 * has announced that it's willing to accept it.
4752 * Hallelujah. Generate a signature and send it.
4754 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4755 ssh2_pkt_addstring(username
);
4756 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4757 ssh2_pkt_addstring("publickey"); /* method */
4758 ssh2_pkt_addbool(TRUE
);
4759 ssh2_pkt_addstring(key
->alg
->name
);
4760 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4761 ssh2_pkt_addstring_start();
4762 ssh2_pkt_addstring_data(pkblob
, pkblob_len
);
4765 * The data to be signed is:
4769 * followed by everything so far placed in the
4772 sigdata_len
= pktout
.length
- 5 + 4 + 20;
4773 sigdata
= smalloc(sigdata_len
);
4774 PUT_32BIT(sigdata
, 20);
4775 memcpy(sigdata
+ 4, ssh2_session_id
, 20);
4776 memcpy(sigdata
+ 24, pktout
.data
+ 5,
4778 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4779 sigdata_len
, &sigblob_len
);
4780 ssh2_add_sigblob(pkblob
, pkblob_len
,
4781 sigblob
, sigblob_len
);
4787 type
= AUTH_TYPE_PUBLICKEY
;
4789 } else if (method
== AUTH_PASSWORD
) {
4791 * We send the password packet lumped tightly together with
4792 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4793 * string long enough to make the total length of the two
4794 * packets constant. This should ensure that a passive
4795 * listener doing traffic analyis can't work out the length
4798 * For this to work, we need an assumption about the
4799 * maximum length of the password packet. I think 256 is
4800 * pretty conservative. Anyone using a password longer than
4801 * that probably doesn't have much to worry about from
4802 * people who find out how long their password is!
4804 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4805 ssh2_pkt_addstring(username
);
4806 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4807 ssh2_pkt_addstring("password");
4808 ssh2_pkt_addbool(FALSE
);
4809 ssh2_pkt_addstring(password
);
4812 * We'll include a string that's an exact multiple of the
4813 * cipher block size. If the cipher is NULL for some
4814 * reason, we don't do this trick at all because we gain
4820 stringlen
= (256 - deferred_len
);
4821 stringlen
+= cscipher
->blksize
- 1;
4822 stringlen
-= (stringlen
% cscipher
->blksize
);
4825 * Temporarily disable actual compression,
4826 * so we can guarantee to get this string
4827 * exactly the length we want it. The
4828 * compression-disabling routine should
4829 * return an integer indicating how many
4830 * bytes we should adjust our string length
4833 stringlen
-= cscomp
->disable_compression();
4835 ssh2_pkt_init(SSH2_MSG_IGNORE
);
4836 ssh2_pkt_addstring_start();
4837 for (i
= 0; i
< stringlen
; i
++) {
4838 char c
= (char) random_byte();
4839 ssh2_pkt_addstring_data(&c
, 1);
4843 ssh_pkt_defersend();
4844 logevent("Sent password");
4845 type
= AUTH_TYPE_PASSWORD
;
4846 } else if (method
== AUTH_KEYBOARD_INTERACTIVE
) {
4847 if (curr_prompt
== 0) {
4848 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4849 ssh2_pkt_adduint32(num_prompts
);
4851 if (need_pw
) { /* only add pw if we just got one! */
4852 ssh2_pkt_addstring(password
);
4853 memset(password
, 0, sizeof(password
));
4856 if (curr_prompt
>= num_prompts
) {
4860 * If there are prompts remaining, we set
4861 * `gotit' so that we won't attempt to get
4862 * another packet. Then we go back round the
4863 * loop and will end up retrieving another
4864 * prompt out of the existing packet. Funky or
4869 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4872 ("No supported authentication methods left to try!\r\n");
4874 ("No supported authentications offered. Disconnecting");
4875 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4876 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4878 ("No supported authentication methods available");
4879 ssh2_pkt_addstring("en"); /* language tag */
4881 ssh_state
= SSH_STATE_CLOSED
;
4885 } while (!we_are_in
);
4888 * Now we're authenticated for the connection protocol. The
4889 * connection protocol will automatically have started at this
4890 * point; there's no need to send SERVICE_REQUEST.
4894 * So now create a channel with a session in it.
4896 ssh_channels
= newtree234(ssh_channelcmp
);
4897 mainchan
= smalloc(sizeof(struct ssh_channel
));
4898 mainchan
->localid
= alloc_channel_id();
4899 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
4900 ssh2_pkt_addstring("session");
4901 ssh2_pkt_adduint32(mainchan
->localid
);
4902 mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
4903 ssh2_pkt_adduint32(mainchan
->v
.v2
.locwindow
); /* our window size */
4904 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
4906 crWaitUntilV(ispkt
);
4907 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
4908 bombout(("Server refused to open a session"));
4910 /* FIXME: error data comes back in FAILURE packet */
4912 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
4913 bombout(("Server's channel confirmation cited wrong channel"));
4916 mainchan
->remoteid
= ssh2_pkt_getuint32();
4917 mainchan
->type
= CHAN_MAINSESSION
;
4918 mainchan
->closes
= 0;
4919 mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
4920 mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
4921 bufchain_init(&mainchan
->v
.v2
.outbuffer
);
4922 add234(ssh_channels
, mainchan
);
4923 logevent("Opened channel for session");
4926 * Potentially enable X11 forwarding.
4928 if (cfg
.x11_forward
) {
4929 char proto
[20], data
[64];
4930 logevent("Requesting X11 forwarding");
4931 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
4932 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
4933 ssh2_pkt_adduint32(mainchan
->remoteid
);
4934 ssh2_pkt_addstring("x11-req");
4935 ssh2_pkt_addbool(1); /* want reply */
4936 ssh2_pkt_addbool(0); /* many connections */
4937 ssh2_pkt_addstring(proto
);
4938 ssh2_pkt_addstring(data
);
4939 ssh2_pkt_adduint32(0); /* screen number */
4943 crWaitUntilV(ispkt
);
4944 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
4945 unsigned i
= ssh2_pkt_getuint32();
4946 struct ssh_channel
*c
;
4947 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
4949 continue; /* nonexistent channel */
4950 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
4952 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4954 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
4955 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
4956 bombout(("Unexpected response to X11 forwarding request:"
4957 " packet type %d", pktin
.type
));
4960 logevent("X11 forwarding refused");
4962 logevent("X11 forwarding enabled");
4963 ssh_X11_fwd_enabled
= TRUE
;
4968 * Enable port forwardings.
4971 static char *e
; /* preserve across crReturn */
4974 int sport
,dport
,sserv
,dserv
;
4975 char sports
[256], dports
[256], host
[256];
4979 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4980 /* Add port forwardings. */
4985 while (*e
&& *e
!= '\t')
4991 while (*e
&& *e
!= ':')
5001 dport
= atoi(dports
);
5005 se
= getservbyname(dports
, NULL
);
5007 dport
= ntohs(se
->s_port
);
5010 "Service lookup failed for destination port \"%s\"",
5015 sport
= atoi(sports
);
5019 se
= getservbyname(sports
, NULL
);
5021 sport
= ntohs(se
->s_port
);
5024 "Service lookup failed for source port \"%s\"",
5029 if (sport
&& dport
) {
5031 pfd_addforward(host
, dport
, sport
);
5032 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
5033 " %s:%.*s%.*s%d%.*s",
5034 sserv ?
strlen(sports
) : 0, sports
,
5035 sserv
, "(", sport
, sserv
, ")",
5037 dserv ?
strlen(dports
) : 0, dports
,
5038 dserv
, "(", dport
, dserv
, ")");
5041 struct ssh_rportfwd
*pf
;
5042 pf
= smalloc(sizeof(*pf
));
5043 strcpy(pf
->dhost
, host
);
5046 if (add234(ssh_rportfwds
, pf
) != pf
) {
5048 "Duplicate remote port forwarding to %s:%d",
5053 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
5054 " forward to %s:%.*s%.*s%d%.*s",
5055 sserv ?
strlen(sports
) : 0, sports
,
5056 sserv
, "(", sport
, sserv
, ")",
5058 dserv ?
strlen(dports
) : 0, dports
,
5059 dserv
, "(", dport
, dserv
, ")");
5061 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
5062 ssh2_pkt_addstring("tcpip-forward");
5063 ssh2_pkt_addbool(1);/* want reply */
5064 if (cfg
.rport_acceptall
)
5065 ssh2_pkt_addstring("0.0.0.0");
5067 ssh2_pkt_addstring("127.0.0.1");
5068 ssh2_pkt_adduint32(sport
);
5072 crWaitUntilV(ispkt
);
5073 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5074 unsigned i
= ssh2_pkt_getuint32();
5075 struct ssh_channel
*c
;
5076 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5078 continue;/* nonexistent channel */
5079 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5081 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5083 if (pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5084 if (pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5085 bombout(("Unexpected response to port "
5086 "forwarding request: packet type %d",
5090 logevent("Server refused this port forwarding");
5092 logevent("Remote port forwarding enabled");
5101 * Potentially enable agent forwarding.
5103 if (cfg
.agentfwd
&& agent_exists()) {
5104 logevent("Requesting OpenSSH-style agent forwarding");
5105 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5106 ssh2_pkt_adduint32(mainchan
->remoteid
);
5107 ssh2_pkt_addstring("auth-agent-req@openssh.com");
5108 ssh2_pkt_addbool(1); /* want reply */
5112 crWaitUntilV(ispkt
);
5113 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5114 unsigned i
= ssh2_pkt_getuint32();
5115 struct ssh_channel
*c
;
5116 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5118 continue; /* nonexistent channel */
5119 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5121 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5123 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5124 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5125 bombout(("Unexpected response to agent forwarding request:"
5126 " packet type %d", pktin
.type
));
5129 logevent("Agent forwarding refused");
5131 logevent("Agent forwarding enabled");
5132 ssh_agentfwd_enabled
= TRUE
;
5137 * Now allocate a pty for the session.
5140 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5141 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5142 ssh2_pkt_addstring("pty-req");
5143 ssh2_pkt_addbool(1); /* want reply */
5144 ssh2_pkt_addstring(cfg
.termtype
);
5145 ssh2_pkt_adduint32(cols
);
5146 ssh2_pkt_adduint32(rows
);
5147 ssh2_pkt_adduint32(0); /* pixel width */
5148 ssh2_pkt_adduint32(0); /* pixel height */
5149 ssh2_pkt_addstring_start();
5150 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
5152 ssh_state
= SSH_STATE_INTERMED
;
5155 crWaitUntilV(ispkt
);
5156 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5157 unsigned i
= ssh2_pkt_getuint32();
5158 struct ssh_channel
*c
;
5159 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5161 continue; /* nonexistent channel */
5162 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5164 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5166 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5167 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5168 bombout(("Unexpected response to pty request:"
5169 " packet type %d", pktin
.type
));
5172 c_write_str("Server refused to allocate pty\r\n");
5173 ssh_editing
= ssh_echoing
= 1;
5175 logevent("Allocated pty");
5178 ssh_editing
= ssh_echoing
= 1;
5182 * Start a shell or a remote command. We may have to attempt
5183 * this twice if the config data has provided a second choice
5190 if (ssh_fallback_cmd
) {
5191 subsys
= cfg
.ssh_subsys2
;
5192 cmd
= cfg
.remote_cmd_ptr2
;
5194 subsys
= cfg
.ssh_subsys
;
5195 cmd
= cfg
.remote_cmd_ptr
;
5198 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5199 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5201 ssh2_pkt_addstring("subsystem");
5202 ssh2_pkt_addbool(1); /* want reply */
5203 ssh2_pkt_addstring(cmd
);
5205 ssh2_pkt_addstring("exec");
5206 ssh2_pkt_addbool(1); /* want reply */
5207 ssh2_pkt_addstring(cmd
);
5209 ssh2_pkt_addstring("shell");
5210 ssh2_pkt_addbool(1); /* want reply */
5214 crWaitUntilV(ispkt
);
5215 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5216 unsigned i
= ssh2_pkt_getuint32();
5217 struct ssh_channel
*c
;
5218 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5220 continue; /* nonexistent channel */
5221 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5223 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5224 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5225 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5226 bombout(("Unexpected response to shell/command request:"
5227 " packet type %d", pktin
.type
));
5231 * We failed to start the command. If this is the
5232 * fallback command, we really are finished; if it's
5233 * not, and if the fallback command exists, try falling
5234 * back to it before complaining.
5236 if (!ssh_fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5237 logevent("Primary command failed; attempting fallback");
5238 ssh_fallback_cmd
= TRUE
;
5241 bombout(("Server refused to start a shell/command"));
5244 logevent("Started a shell/command");
5249 ssh_state
= SSH_STATE_SESSION
;
5253 ssh_special(TS_EOF
);
5258 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
5261 static int try_send
;
5265 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5266 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5269 unsigned i
= ssh2_pkt_getuint32();
5270 struct ssh_channel
*c
;
5271 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5273 continue; /* nonexistent channel */
5274 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5275 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
5276 continue; /* extended but not stderr */
5277 ssh2_pkt_getstring(&data
, &length
);
5280 c
->v
.v2
.locwindow
-= length
;
5282 case CHAN_MAINSESSION
:
5284 from_backend(pktin
.type
==
5285 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5289 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5292 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5295 while (length
> 0) {
5296 if (c
->u
.a
.lensofar
< 4) {
5297 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5298 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5302 c
->u
.a
.lensofar
+= l
;
5304 if (c
->u
.a
.lensofar
== 4) {
5306 4 + GET_32BIT(c
->u
.a
.msglen
);
5307 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5308 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5310 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5312 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5314 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5318 c
->u
.a
.lensofar
+= l
;
5320 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5321 void *reply
, *sentreply
;
5323 agent_query(c
->u
.a
.message
,
5324 c
->u
.a
.totallen
, &reply
,
5329 /* Fake SSH_AGENT_FAILURE. */
5330 sentreply
= "\0\0\0\1\5";
5333 ssh2_add_channel_data(c
, sentreply
,
5338 sfree(c
->u
.a
.message
);
5339 c
->u
.a
.lensofar
= 0;
5346 * If we are not buffering too much data,
5347 * enlarge the window again at the remote side.
5349 if (bufsize
< OUR_V2_WINSIZE
)
5350 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5352 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
5353 ssh_state
= SSH_STATE_CLOSED
;
5354 logevent("Received disconnect message");
5356 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5357 unsigned i
= ssh2_pkt_getuint32();
5358 struct ssh_channel
*c
;
5360 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5362 continue; /* nonexistent channel */
5364 if (c
->type
== CHAN_X11
) {
5366 * Remote EOF on an X11 channel means we should
5367 * wrap up and close the channel ourselves.
5369 x11_close(c
->u
.x11
.s
);
5371 } else if (c
->type
== CHAN_AGENT
) {
5373 } else if (c
->type
== CHAN_SOCKDATA
) {
5374 pfd_close(c
->u
.pfd
.s
);
5377 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5378 unsigned i
= ssh2_pkt_getuint32();
5379 struct ssh_channel
*c
;
5381 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5382 if (!c
|| ((int)c
->remoteid
) == -1) {
5383 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5384 c ?
"half-open" : "nonexistent", i
));
5386 /* Do pre-close processing on the channel. */
5388 case CHAN_MAINSESSION
:
5389 break; /* nothing to see here, move along */
5391 if (c
->u
.x11
.s
!= NULL
)
5392 x11_close(c
->u
.x11
.s
);
5399 if (c
->u
.pfd
.s
!= NULL
)
5400 pfd_close(c
->u
.pfd
.s
);
5404 if (c
->closes
== 0) {
5405 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5406 ssh2_pkt_adduint32(c
->remoteid
);
5409 del234(ssh_channels
, c
);
5410 bufchain_clear(&c
->v
.v2
.outbuffer
);
5414 * See if that was the last channel left open.
5416 if (count234(ssh_channels
) == 0) {
5419 * We used to send SSH_MSG_DISCONNECT here,
5420 * because I'd believed that _every_ conforming
5421 * SSH2 connection had to end with a disconnect
5422 * being sent by at least one side; apparently
5423 * I was wrong and it's perfectly OK to
5424 * unceremoniously slam the connection shut
5425 * when you're done, and indeed OpenSSH feels
5426 * this is more polite than sending a
5427 * DISCONNECT. So now we don't.
5429 logevent("All channels closed. Disconnecting");
5430 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5431 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5432 ssh2_pkt_addstring("All open channels closed");
5433 ssh2_pkt_addstring("en"); /* language tag */
5436 ssh_state
= SSH_STATE_CLOSED
;
5439 continue; /* remote sends close; ignore (FIXME) */
5440 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5441 unsigned i
= ssh2_pkt_getuint32();
5442 struct ssh_channel
*c
;
5443 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5445 continue; /* nonexistent channel */
5446 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5448 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5449 unsigned i
= ssh2_pkt_getuint32();
5450 struct ssh_channel
*c
;
5451 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5453 continue; /* nonexistent channel */
5454 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5455 continue; /* dunno why they're confirming this */
5456 c
->remoteid
= ssh2_pkt_getuint32();
5457 c
->type
= CHAN_SOCKDATA
;
5458 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
5459 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
5461 pfd_confirm(c
->u
.pfd
.s
);
5464 * We have a pending close on this channel,
5465 * which we decided on before the server acked
5466 * the channel open. So now we know the
5467 * remoteid, we can close it again.
5469 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5470 ssh2_pkt_adduint32(c
->remoteid
);
5473 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5474 unsigned i
= ssh2_pkt_getuint32();
5475 struct ssh_channel
*c
;
5476 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5478 continue; /* nonexistent channel */
5479 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5480 continue; /* dunno why they're failing this */
5482 logevent("Forwarded connection refused by server");
5484 pfd_close(c
->u
.pfd
.s
);
5486 del234(ssh_channels
, c
);
5488 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5491 int typelen
, want_reply
;
5492 struct ssh_channel
*c
;
5494 localid
= ssh2_pkt_getuint32();
5495 ssh2_pkt_getstring(&type
, &typelen
);
5496 want_reply
= ssh2_pkt_getbool();
5499 * First, check that the channel exists. Otherwise,
5500 * we can instantly disconnect with a rude message.
5502 c
= find234(ssh_channels
, &localid
, ssh_channelfind
);
5505 sprintf(buf
, "Received channel request for nonexistent"
5506 " channel %d", localid
);
5508 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5509 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5510 ssh2_pkt_addstring(buf
);
5511 ssh2_pkt_addstring("en"); /* language tag */
5513 connection_fatal("%s", buf
);
5514 ssh_state
= SSH_STATE_CLOSED
;
5519 * Having got the channel number, we now look at
5520 * the request type string to see if it's something
5523 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5525 /* We recognise "exit-status" on the primary channel. */
5527 ssh_exitcode
= ssh2_pkt_getuint32();
5528 sprintf(buf
, "Server sent command exit status %d",
5532 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS
);
5533 ssh2_pkt_adduint32(c
->remoteid
);
5538 * This is a channel request we don't know
5539 * about, so we now either ignore the request
5540 * or respond with CHANNEL_FAILURE, depending
5544 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE
);
5545 ssh2_pkt_adduint32(c
->remoteid
);
5549 } else if (pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5551 int typelen
, want_reply
;
5553 ssh2_pkt_getstring(&type
, &typelen
);
5554 want_reply
= ssh2_pkt_getbool();
5557 * We currently don't support any global requests
5558 * at all, so we either ignore the request or
5559 * respond with REQUEST_FAILURE, depending on
5563 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5566 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5570 struct ssh_channel
*c
;
5571 unsigned remid
, winsize
, pktsize
;
5572 ssh2_pkt_getstring(&type
, &typelen
);
5573 c
= smalloc(sizeof(struct ssh_channel
));
5575 remid
= ssh2_pkt_getuint32();
5576 winsize
= ssh2_pkt_getuint32();
5577 pktsize
= ssh2_pkt_getuint32();
5579 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5580 if (!ssh_X11_fwd_enabled
)
5581 error
= "X11 forwarding is not enabled";
5582 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5584 error
= "Unable to open an X11 connection";
5588 } else if (typelen
== 15 &&
5589 !memcmp(type
, "forwarded-tcpip", 15)) {
5590 struct ssh_rportfwd pf
, *realpf
;
5593 ssh2_pkt_getstring(&dummy
, &dummylen
);/* skip address */
5594 pf
.sport
= ssh2_pkt_getuint32();
5595 realpf
= find234(ssh_rportfwds
, &pf
, NULL
);
5596 if (realpf
== NULL
) {
5597 error
= "Remote port is not recognised";
5599 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5602 sprintf(buf
, "Received remote port open request for %s:%d",
5603 realpf
->dhost
, realpf
->dport
);
5606 sprintf(buf
, "Port open failed: %s", e
);
5608 error
= "Port open failed";
5610 logevent("Forwarded port opened successfully");
5611 c
->type
= CHAN_SOCKDATA
;
5614 } else if (typelen
== 22 &&
5615 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5616 if (!ssh_agentfwd_enabled
)
5617 error
= "Agent forwarding is not enabled";
5619 c
->type
= CHAN_AGENT
; /* identify channel type */
5620 c
->u
.a
.lensofar
= 0;
5623 error
= "Unsupported channel type requested";
5626 c
->remoteid
= remid
;
5628 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5629 ssh2_pkt_adduint32(c
->remoteid
);
5630 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
5631 ssh2_pkt_addstring(error
);
5632 ssh2_pkt_addstring("en"); /* language tag */
5636 c
->localid
= alloc_channel_id();
5638 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5639 c
->v
.v2
.remwindow
= winsize
;
5640 c
->v
.v2
.remmaxpkt
= pktsize
;
5641 bufchain_init(&c
->v
.v2
.outbuffer
);
5642 add234(ssh_channels
, c
);
5643 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5644 ssh2_pkt_adduint32(c
->remoteid
);
5645 ssh2_pkt_adduint32(c
->localid
);
5646 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);
5647 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5651 bombout(("Strange packet received: type %d", pktin
.type
));
5656 * We have spare data. Add it to the channel buffer.
5658 ssh2_add_channel_data(mainchan
, in
, inlen
);
5663 struct ssh_channel
*c
;
5665 * Try to send data on all channels if we can.
5667 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
5668 int bufsize
= ssh2_try_send(c
);
5671 case CHAN_MAINSESSION
:
5672 /* stdin need not receive an unthrottle
5673 * notification since it will be polled */
5676 x11_unthrottle(c
->u
.x11
.s
);
5679 /* agent sockets are request/response and need no
5680 * buffer management */
5683 pfd_unthrottle(c
->u
.pfd
.s
);
5695 * Handle the top-level SSH2 protocol.
5697 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
5699 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
5701 do_ssh2_authconn(in
, inlen
, ispkt
);
5705 * Called to set up the connection.
5707 * Returns an error message, or NULL on success.
5709 static char *ssh_init(char *host
, int port
, char **realhost
, int nodelay
)
5714 if (crypto_startup() == 0)
5715 return "Microsoft high encryption pack not installed!";
5721 ssh1_throttle_count
= 0;
5722 ssh_overall_bufsize
= 0;
5723 ssh_fallback_cmd
= 0;
5725 p
= connect_to_host(host
, port
, realhost
, nodelay
);
5733 * Called to send data down the Telnet connection.
5735 static int ssh_send(char *buf
, int len
)
5737 if (s
== NULL
|| ssh_protocol
== NULL
)
5740 ssh_protocol(buf
, len
, 0);
5742 return ssh_sendbuffer();
5746 * Called to query the current amount of buffered stdin data.
5748 static int ssh_sendbuffer(void)
5752 if (s
== NULL
|| ssh_protocol
== NULL
)
5756 * If the SSH socket itself has backed up, add the total backup
5757 * size on that to any individual buffer on the stdin channel.
5760 if (ssh_throttled_all
)
5761 override_value
= ssh_overall_bufsize
;
5763 if (ssh_version
== 1) {
5764 return override_value
;
5765 } else if (ssh_version
== 2) {
5766 if (!mainchan
|| mainchan
->closes
> 0)
5767 return override_value
;
5769 return override_value
+ bufchain_size(&mainchan
->v
.v2
.outbuffer
);
5776 * Called to set the size of the window from SSH's POV.
5778 static void ssh_size(void)
5780 switch (ssh_state
) {
5781 case SSH_STATE_BEFORE_SIZE
:
5782 case SSH_STATE_PREPACKET
:
5783 case SSH_STATE_CLOSED
:
5784 break; /* do nothing */
5785 case SSH_STATE_INTERMED
:
5786 size_needed
= TRUE
; /* buffer for later */
5788 case SSH_STATE_SESSION
:
5790 if (ssh_version
== 1) {
5791 send_packet(SSH1_CMSG_WINDOW_SIZE
,
5792 PKT_INT
, rows
, PKT_INT
, cols
,
5793 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5795 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5796 ssh2_pkt_adduint32(mainchan
->remoteid
);
5797 ssh2_pkt_addstring("window-change");
5798 ssh2_pkt_addbool(0);
5799 ssh2_pkt_adduint32(cols
);
5800 ssh2_pkt_adduint32(rows
);
5801 ssh2_pkt_adduint32(0);
5802 ssh2_pkt_adduint32(0);
5811 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5812 * can send an EOF and collect resulting output (e.g. `plink
5815 static void ssh_special(Telnet_Special code
)
5817 if (code
== TS_EOF
) {
5818 if (ssh_state
!= SSH_STATE_SESSION
) {
5820 * Buffer the EOF in case we are pre-SESSION, so we can
5821 * send it as soon as we reach SESSION.
5827 if (ssh_version
== 1) {
5828 send_packet(SSH1_CMSG_EOF
, PKT_END
);
5830 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
5831 ssh2_pkt_adduint32(mainchan
->remoteid
);
5834 logevent("Sent EOF message");
5835 } else if (code
== TS_PING
) {
5836 if (ssh_state
== SSH_STATE_CLOSED
5837 || ssh_state
== SSH_STATE_PREPACKET
) return;
5838 if (ssh_version
== 1) {
5839 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
5840 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
5842 ssh2_pkt_init(SSH2_MSG_IGNORE
);
5843 ssh2_pkt_addstring_start();
5851 void *new_sock_channel(Socket s
)
5853 struct ssh_channel
*c
;
5854 c
= smalloc(sizeof(struct ssh_channel
));
5857 c
->remoteid
= -1; /* to be set when open confirmed */
5858 c
->localid
= alloc_channel_id();
5860 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
5862 bufchain_init(&c
->v
.v2
.outbuffer
);
5863 add234(ssh_channels
, c
);
5869 * This is called when stdout/stderr (the entity to which
5870 * from_backend sends data) manages to clear some backlog.
5872 void ssh_unthrottle(int bufsize
)
5874 if (ssh_version
== 1) {
5875 if (ssh1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
5876 ssh1_stdout_throttling
= 0;
5880 if (mainchan
&& mainchan
->closes
== 0)
5881 ssh2_set_window(mainchan
, OUR_V2_WINSIZE
- bufsize
);
5885 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
5887 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
5890 sprintf(buf
, "Opening forwarded connection to %.512s:%d", hostname
, port
);
5893 if (ssh_version
== 1) {
5894 send_packet(SSH1_MSG_PORT_OPEN
,
5895 PKT_INT
, c
->localid
,
5898 //PKT_STR, <org:orgport>,
5901 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
5902 ssh2_pkt_addstring("direct-tcpip");
5903 ssh2_pkt_adduint32(c
->localid
);
5904 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5905 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);/* our window size */
5906 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5907 ssh2_pkt_addstring(hostname
);
5908 ssh2_pkt_adduint32(port
);
5910 * We make up values for the originator data; partly it's
5911 * too much hassle to keep track, and partly I'm not
5912 * convinced the server should be told details like that
5913 * about my local network configuration.
5915 ssh2_pkt_addstring("client-side-connection");
5916 ssh2_pkt_adduint32(0);
5922 static Socket
ssh_socket(void)
5927 static int ssh_sendok(void)
5932 static int ssh_ldisc(int option
)
5934 if (option
== LD_ECHO
)
5936 if (option
== LD_EDIT
)
5941 static int ssh_return_exitcode(void)
5943 return ssh_exitcode
;
5946 Backend ssh_backend
= {
5953 ssh_return_exitcode
,