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 void *frontend
;
538 static int ssh_term_width
, ssh_term_height
;
540 static tree234
*ssh_channels
; /* indexed by local id */
541 static struct ssh_channel
*mainchan
; /* primary session channel */
542 static int ssh_exitcode
= -1;
544 static tree234
*ssh_rportfwds
;
548 SSH_STATE_BEFORE_SIZE
,
552 } ssh_state
= SSH_STATE_PREPACKET
;
554 static int size_needed
= FALSE
, eof_needed
= FALSE
;
556 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
557 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
558 static unsigned char *deferred_send_data
= NULL
;
559 static int deferred_len
= 0, deferred_size
= 0;
562 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
563 * that fails. This variable is the means by which scp.c can reach
564 * into the SSH code and find out which one it got.
566 int ssh_fallback_cmd
= 0;
568 static int ssh_version
;
569 static int ssh1_throttle_count
;
570 static int ssh_overall_bufsize
;
571 static int ssh_throttled_all
;
572 static int ssh1_stdout_throttling
;
573 static void (*ssh_protocol
) (unsigned char *in
, int inlen
, int ispkt
);
574 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
575 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
576 static void ssh_size(int width
, int height
);
577 static void ssh_special(Telnet_Special
);
578 static int ssh2_try_send(struct ssh_channel
*c
);
579 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
581 static void ssh_throttle_all(int enable
, int bufsize
);
582 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
583 static int (*s_rdpkt
) (unsigned char **data
, int *datalen
);
584 static int ssh_sendbuffer(void);
586 static struct rdpkt1_state_tag
{
587 long len
, pad
, biglen
, to_read
;
588 unsigned long realcrc
, gotcrc
;
594 static struct rdpkt2_state_tag
{
595 long len
, pad
, payload
, packetlen
, maclen
;
598 unsigned long incoming_sequence
;
601 static int ssh_channelcmp(void *av
, void *bv
)
603 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
604 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
605 if (a
->localid
< b
->localid
)
607 if (a
->localid
> b
->localid
)
611 static int ssh_channelfind(void *av
, void *bv
)
613 unsigned *a
= (unsigned *) av
;
614 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
622 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
624 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
625 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
627 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
628 return i
< 0 ?
-1 : +1;
629 if (a
->dport
> b
->dport
)
631 if (a
->dport
< b
->dport
)
636 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
638 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
639 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
641 if (a
->sport
> b
->sport
)
643 if (a
->sport
< b
->sport
)
648 static int alloc_channel_id(void)
650 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
651 unsigned low
, high
, mid
;
653 struct ssh_channel
*c
;
656 * First-fit allocation of channel numbers: always pick the
657 * lowest unused one. To do this, binary-search using the
658 * counted B-tree to find the largest channel ID which is in a
659 * contiguous sequence from the beginning. (Precisely
660 * everything in that sequence must have ID equal to its tree
661 * index plus CHANNEL_NUMBER_OFFSET.)
663 tsize
= count234(ssh_channels
);
667 while (high
- low
> 1) {
668 mid
= (high
+ low
) / 2;
669 c
= index234(ssh_channels
, mid
);
670 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
671 low
= mid
; /* this one is fine */
673 high
= mid
; /* this one is past it */
676 * Now low points to either -1, or the tree index of the
677 * largest ID in the initial sequence.
680 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
681 assert(NULL
== find234(ssh_channels
, &i
, ssh_channelfind
));
683 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
686 static void c_write(char *buf
, int len
)
688 if ((flags
& FLAG_STDERR
)) {
690 for (i
= 0; i
< len
; i
++)
692 fputc(buf
[i
], stderr
);
695 from_backend(frontend
, 1, buf
, len
);
698 static void c_write_untrusted(char *buf
, int len
)
701 for (i
= 0; i
< len
; i
++) {
704 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
709 static void c_write_str(char *buf
)
711 c_write(buf
, strlen(buf
));
715 * Collect incoming data in the incoming packet buffer.
716 * Decipher and verify the packet when it is completely read.
717 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
718 * Update the *data and *datalen variables.
719 * Return the additional nr of bytes needed, or 0 when
720 * a complete packet is available.
722 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
724 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
733 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
734 while ((*datalen
) == 0)
736 st
->len
= (st
->len
<< 8) + **data
;
737 (*data
)++, (*datalen
)--;
740 st
->pad
= 8 - (st
->len
% 8);
741 st
->biglen
= st
->len
+ st
->pad
;
742 pktin
.length
= st
->len
- 5;
744 if (pktin
.maxlen
< st
->biglen
) {
745 pktin
.maxlen
= st
->biglen
;
746 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+ APIEXTRA
) :
747 srealloc(pktin
.data
, st
->biglen
+ APIEXTRA
));
749 fatalbox("Out of memory");
752 st
->to_read
= st
->biglen
;
754 while (st
->to_read
> 0) {
755 st
->chunk
= st
->to_read
;
756 while ((*datalen
) == 0)
757 crReturn(st
->to_read
);
758 if (st
->chunk
> (*datalen
))
759 st
->chunk
= (*datalen
);
760 memcpy(st
->p
, *data
, st
->chunk
);
762 *datalen
-= st
->chunk
;
764 st
->to_read
-= st
->chunk
;
767 if (cipher
&& detect_attack(pktin
.data
, st
->biglen
, NULL
)) {
768 bombout(("Network attack (CRC compensation) detected!"));
773 cipher
->decrypt(pktin
.data
, st
->biglen
);
775 st
->realcrc
= crc32(pktin
.data
, st
->biglen
- 4);
776 st
->gotcrc
= GET_32BIT(pktin
.data
+ st
->biglen
- 4);
777 if (st
->gotcrc
!= st
->realcrc
) {
778 bombout(("Incorrect CRC received on packet"));
782 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
784 if (ssh1_compressing
) {
785 unsigned char *decompblk
;
787 zlib_decompress_block(pktin
.body
- 1, pktin
.length
+ 1,
788 &decompblk
, &decomplen
);
790 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
791 pktin
.maxlen
= st
->pad
+ decomplen
;
792 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+ APIEXTRA
);
793 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
795 fatalbox("Out of memory");
798 memcpy(pktin
.body
- 1, decompblk
, decomplen
);
800 pktin
.length
= decomplen
- 1;
803 pktin
.type
= pktin
.body
[-1];
805 log_packet(PKT_INCOMING
, pktin
.type
, ssh1_pkt_type(pktin
.type
),
806 pktin
.body
, pktin
.length
);
808 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
809 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
810 pktin
.type
== SSH1_MSG_DEBUG
||
811 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
812 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
813 long stringlen
= GET_32BIT(pktin
.body
);
814 if (stringlen
+ 4 != pktin
.length
) {
815 bombout(("Received data packet with bogus string length"));
820 if (pktin
.type
== SSH1_MSG_DEBUG
) {
821 /* log debug message */
823 int stringlen
= GET_32BIT(pktin
.body
);
824 strcpy(buf
, "Remote debug message: ");
827 memcpy(buf
+ 8, pktin
.body
+ 4, stringlen
);
828 buf
[8 + stringlen
] = '\0';
831 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
836 if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
837 /* log reason code in disconnect message */
839 unsigned msglen
= GET_32BIT(pktin
.body
);
841 strcpy(buf
, "Remote sent disconnect: ");
842 nowlen
= strlen(buf
);
843 if (msglen
> sizeof(buf
) - nowlen
- 1)
844 msglen
= sizeof(buf
) - nowlen
- 1;
845 memcpy(buf
+ nowlen
, pktin
.body
+ 4, msglen
);
846 buf
[nowlen
+ msglen
] = '\0';
847 /* logevent(buf); (this is now done within the bombout macro) */
848 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
855 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
857 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
865 st
->cipherblk
= sccipher
->blksize
;
868 if (st
->cipherblk
< 8)
871 if (pktin
.maxlen
< st
->cipherblk
) {
872 pktin
.maxlen
= st
->cipherblk
;
875 NULL ?
smalloc(st
->cipherblk
+
876 APIEXTRA
) : srealloc(pktin
.data
,
880 fatalbox("Out of memory");
884 * Acquire and decrypt the first block of the packet. This will
885 * contain the length and padding details.
887 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
888 while ((*datalen
) == 0)
889 crReturn(st
->cipherblk
- st
->i
);
890 pktin
.data
[st
->i
] = *(*data
)++;
895 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
898 * Now get the length and padding figures.
900 st
->len
= GET_32BIT(pktin
.data
);
901 st
->pad
= pktin
.data
[4];
904 * _Completely_ silly lengths should be stomped on before they
905 * do us any more damage.
907 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
908 bombout(("Incoming packet was garbled on decryption"));
913 * This enables us to deduce the payload length.
915 st
->payload
= st
->len
- st
->pad
- 1;
917 pktin
.length
= st
->payload
+ 5;
920 * So now we can work out the total packet length.
922 st
->packetlen
= st
->len
+ 4;
923 st
->maclen
= scmac ? scmac
->len
: 0;
926 * Adjust memory allocation if packet is too big.
928 if (pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
929 pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
932 NULL ?
smalloc(pktin
.maxlen
+ APIEXTRA
) : srealloc(pktin
.data
,
937 fatalbox("Out of memory");
941 * Read and decrypt the remainder of the packet.
943 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
945 while ((*datalen
) == 0)
946 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
947 pktin
.data
[st
->i
] = *(*data
)++;
950 /* Decrypt everything _except_ the MAC. */
952 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
953 st
->packetlen
- st
->cipherblk
);
959 && !scmac
->verify(pktin
.data
, st
->len
+ 4,
960 st
->incoming_sequence
)) {
961 bombout(("Incorrect MAC received on packet"));
964 st
->incoming_sequence
++; /* whether or not we MACed */
967 * Decompress packet payload.
970 unsigned char *newpayload
;
972 if (sccomp
&& sccomp
->decompress(pktin
.data
+ 5, pktin
.length
- 5,
973 &newpayload
, &newlen
)) {
974 if (pktin
.maxlen
< newlen
+ 5) {
975 pktin
.maxlen
= newlen
+ 5;
978 NULL ?
smalloc(pktin
.maxlen
+
979 APIEXTRA
) : srealloc(pktin
.data
,
983 fatalbox("Out of memory");
985 pktin
.length
= 5 + newlen
;
986 memcpy(pktin
.data
+ 5, newpayload
, newlen
);
992 pktin
.type
= pktin
.data
[5];
994 log_packet(PKT_INCOMING
, pktin
.type
, ssh2_pkt_type(pktin
.type
),
995 pktin
.data
+6, pktin
.length
-6);
997 switch (pktin
.type
) {
999 * These packets we must handle instantly.
1001 case SSH2_MSG_DISCONNECT
:
1003 /* log reason code in disconnect message */
1005 int reason
= GET_32BIT(pktin
.data
+ 6);
1006 unsigned msglen
= GET_32BIT(pktin
.data
+ 10);
1008 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1009 sprintf(buf
, "Received disconnect message (%s)",
1010 ssh2_disconnect_reasons
[reason
]);
1012 sprintf(buf
, "Received disconnect message (unknown type %d)",
1016 strcpy(buf
, "Disconnection message text: ");
1017 nowlen
= strlen(buf
);
1018 if (msglen
> sizeof(buf
) - nowlen
- 1)
1019 msglen
= sizeof(buf
) - nowlen
- 1;
1020 memcpy(buf
+ nowlen
, pktin
.data
+ 14, msglen
);
1021 buf
[nowlen
+ msglen
] = '\0';
1023 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1025 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1026 ssh2_disconnect_reasons
[reason
] : "unknown",
1031 case SSH2_MSG_IGNORE
:
1033 case SSH2_MSG_DEBUG
:
1035 /* log the debug message */
1037 /* int display = pktin.body[6]; */
1038 int stringlen
= GET_32BIT(pktin
.data
+7);
1040 strcpy(buf
, "Remote debug message: ");
1041 prefix
= strlen(buf
);
1042 if (stringlen
> sizeof(buf
)-prefix
-1)
1043 stringlen
= sizeof(buf
)-prefix
-1;
1044 memcpy(buf
+ prefix
, pktin
.data
+ 11, stringlen
);
1045 buf
[prefix
+ stringlen
] = '\0';
1048 goto next_packet
; /* FIXME: print the debug message */
1051 * These packets we need do nothing about here.
1053 case SSH2_MSG_UNIMPLEMENTED
:
1054 case SSH2_MSG_SERVICE_REQUEST
:
1055 case SSH2_MSG_SERVICE_ACCEPT
:
1056 case SSH2_MSG_KEXINIT
:
1057 case SSH2_MSG_NEWKEYS
:
1058 case SSH2_MSG_KEXDH_INIT
:
1059 case SSH2_MSG_KEXDH_REPLY
:
1060 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1061 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1062 case SSH2_MSG_KEX_DH_GEX_INIT
:
1063 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1064 case SSH2_MSG_USERAUTH_REQUEST
:
1065 case SSH2_MSG_USERAUTH_FAILURE
:
1066 case SSH2_MSG_USERAUTH_SUCCESS
:
1067 case SSH2_MSG_USERAUTH_BANNER
:
1068 case SSH2_MSG_USERAUTH_PK_OK
:
1069 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1070 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1071 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1072 case SSH2_MSG_GLOBAL_REQUEST
:
1073 case SSH2_MSG_REQUEST_SUCCESS
:
1074 case SSH2_MSG_REQUEST_FAILURE
:
1075 case SSH2_MSG_CHANNEL_OPEN
:
1076 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1077 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1078 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1079 case SSH2_MSG_CHANNEL_DATA
:
1080 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1081 case SSH2_MSG_CHANNEL_EOF
:
1082 case SSH2_MSG_CHANNEL_CLOSE
:
1083 case SSH2_MSG_CHANNEL_REQUEST
:
1084 case SSH2_MSG_CHANNEL_SUCCESS
:
1085 case SSH2_MSG_CHANNEL_FAILURE
:
1089 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1092 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
1093 ssh2_pkt_adduint32(st
->incoming_sequence
- 1);
1101 static void ssh1_pktout_size(int len
)
1105 len
+= 5; /* type and CRC */
1106 pad
= 8 - (len
% 8);
1109 pktout
.length
= len
- 5;
1110 if (pktout
.maxlen
< biglen
) {
1111 pktout
.maxlen
= biglen
;
1113 /* Allocate enough buffer space for extra block
1114 * for MS CryptEncrypt() */
1115 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 12) :
1116 srealloc(pktout
.data
, biglen
+ 12));
1118 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+ 4) :
1119 srealloc(pktout
.data
, biglen
+ 4));
1122 fatalbox("Out of memory");
1124 pktout
.body
= pktout
.data
+ 4 + pad
+ 1;
1127 static void s_wrpkt_start(int type
, int len
)
1129 ssh1_pktout_size(len
);
1133 static int s_wrpkt_prepare(void)
1135 int pad
, len
, biglen
, i
;
1138 pktout
.body
[-1] = pktout
.type
;
1140 log_packet(PKT_OUTGOING
, pktout
.type
, ssh1_pkt_type(pktout
.type
),
1141 pktout
.body
, pktout
.length
);
1143 if (ssh1_compressing
) {
1144 unsigned char *compblk
;
1146 zlib_compress_block(pktout
.body
- 1, pktout
.length
+ 1,
1147 &compblk
, &complen
);
1148 ssh1_pktout_size(complen
- 1);
1149 memcpy(pktout
.body
- 1, compblk
, complen
);
1153 len
= pktout
.length
+ 5; /* type and CRC */
1154 pad
= 8 - (len
% 8);
1157 for (i
= 0; i
< pad
; i
++)
1158 pktout
.data
[i
+ 4] = random_byte();
1159 crc
= crc32(pktout
.data
+ 4, biglen
- 4);
1160 PUT_32BIT(pktout
.data
+ biglen
, crc
);
1161 PUT_32BIT(pktout
.data
, len
);
1164 cipher
->encrypt(pktout
.data
+ 4, biglen
);
1169 static void s_wrpkt(void)
1172 len
= s_wrpkt_prepare();
1173 backlog
= sk_write(s
, pktout
.data
, len
);
1174 if (backlog
> SSH_MAX_BACKLOG
)
1175 ssh_throttle_all(1, backlog
);
1178 static void s_wrpkt_defer(void)
1181 len
= s_wrpkt_prepare();
1182 if (deferred_len
+ len
> deferred_size
) {
1183 deferred_size
= deferred_len
+ len
+ 128;
1184 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1186 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1187 deferred_len
+= len
;
1191 * Construct a packet with the specified contents.
1193 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
1195 unsigned char *p
, *argp
, argchar
;
1196 unsigned long argint
;
1197 int pktlen
, argtype
, arglen
;
1201 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1204 (void) va_arg(ap1
, int);
1208 (void) va_arg(ap1
, char);
1212 (void) va_arg(ap1
, unsigned char *);
1213 arglen
= va_arg(ap1
, int);
1217 argp
= va_arg(ap1
, unsigned char *);
1218 arglen
= strlen(argp
);
1219 pktlen
+= 4 + arglen
;
1222 bn
= va_arg(ap1
, Bignum
);
1223 pktlen
+= ssh1_bignum_length(bn
);
1230 s_wrpkt_start(pkttype
, pktlen
);
1233 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1236 argint
= va_arg(ap2
, int);
1237 PUT_32BIT(p
, argint
);
1241 argchar
= va_arg(ap2
, unsigned char);
1246 argp
= va_arg(ap2
, unsigned char *);
1247 arglen
= va_arg(ap2
, int);
1248 memcpy(p
, argp
, arglen
);
1252 argp
= va_arg(ap2
, unsigned char *);
1253 arglen
= strlen(argp
);
1254 PUT_32BIT(p
, arglen
);
1255 memcpy(p
+ 4, argp
, arglen
);
1259 bn
= va_arg(ap2
, Bignum
);
1260 p
+= ssh1_write_bignum(p
, bn
);
1266 static void send_packet(int pkttype
, ...)
1269 va_start(ap1
, pkttype
);
1270 va_start(ap2
, pkttype
);
1271 construct_packet(pkttype
, ap1
, ap2
);
1275 static void defer_packet(int pkttype
, ...)
1278 va_start(ap1
, pkttype
);
1279 va_start(ap2
, pkttype
);
1280 construct_packet(pkttype
, ap1
, ap2
);
1284 static int ssh_versioncmp(char *a
, char *b
)
1287 unsigned long av
, bv
;
1289 av
= strtoul(a
, &ae
, 10);
1290 bv
= strtoul(b
, &be
, 10);
1292 return (av
< bv ?
-1 : +1);
1297 av
= strtoul(ae
, &ae
, 10);
1298 bv
= strtoul(be
, &be
, 10);
1300 return (av
< bv ?
-1 : +1);
1306 * Utility routines for putting an SSH-protocol `string' and
1307 * `uint32' into a SHA state.
1310 static void sha_string(SHA_State
* s
, void *str
, int len
)
1312 unsigned char lenblk
[4];
1313 PUT_32BIT(lenblk
, len
);
1314 SHA_Bytes(s
, lenblk
, 4);
1315 SHA_Bytes(s
, str
, len
);
1318 static void sha_uint32(SHA_State
* s
, unsigned i
)
1320 unsigned char intblk
[4];
1321 PUT_32BIT(intblk
, i
);
1322 SHA_Bytes(s
, intblk
, 4);
1326 * SSH2 packet construction functions.
1328 static void ssh2_pkt_ensure(int length
)
1330 if (pktout
.maxlen
< length
) {
1331 pktout
.maxlen
= length
+ 256;
1334 NULL ?
smalloc(pktout
.maxlen
+
1335 APIEXTRA
) : srealloc(pktout
.data
,
1339 fatalbox("Out of memory");
1342 static void ssh2_pkt_adddata(void *data
, int len
)
1344 pktout
.length
+= len
;
1345 ssh2_pkt_ensure(pktout
.length
);
1346 memcpy(pktout
.data
+ pktout
.length
- len
, data
, len
);
1348 static void ssh2_pkt_addbyte(unsigned char byte
)
1350 ssh2_pkt_adddata(&byte
, 1);
1352 static void ssh2_pkt_init(int pkt_type
)
1355 ssh2_pkt_addbyte((unsigned char) pkt_type
);
1357 static void ssh2_pkt_addbool(unsigned char value
)
1359 ssh2_pkt_adddata(&value
, 1);
1361 static void ssh2_pkt_adduint32(unsigned long value
)
1364 PUT_32BIT(x
, value
);
1365 ssh2_pkt_adddata(x
, 4);
1367 static void ssh2_pkt_addstring_start(void)
1369 ssh2_pkt_adduint32(0);
1370 pktout
.savedpos
= pktout
.length
;
1372 static void ssh2_pkt_addstring_str(char *data
)
1374 ssh2_pkt_adddata(data
, strlen(data
));
1375 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1376 pktout
.length
- pktout
.savedpos
);
1378 static void ssh2_pkt_addstring_data(char *data
, int len
)
1380 ssh2_pkt_adddata(data
, len
);
1381 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
1382 pktout
.length
- pktout
.savedpos
);
1384 static void ssh2_pkt_addstring(char *data
)
1386 ssh2_pkt_addstring_start();
1387 ssh2_pkt_addstring_str(data
);
1389 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1392 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1395 fatalbox("out of memory");
1397 for (i
= 1; i
<= n
; i
++)
1398 p
[i
] = bignum_byte(b
, n
- i
);
1400 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1402 memmove(p
, p
+ i
, n
+ 1 - i
);
1406 static void ssh2_pkt_addmp(Bignum b
)
1410 p
= ssh2_mpint_fmt(b
, &len
);
1411 ssh2_pkt_addstring_start();
1412 ssh2_pkt_addstring_data(p
, len
);
1417 * Construct an SSH2 final-form packet: compress it, encrypt it,
1418 * put the MAC on it. Final packet, ready to be sent, is stored in
1419 * pktout.data. Total length is returned.
1421 static int ssh2_pkt_construct(void)
1423 int cipherblk
, maclen
, padding
, i
;
1424 static unsigned long outgoing_sequence
= 0;
1426 log_packet(PKT_OUTGOING
, pktout
.data
[5], ssh2_pkt_type(pktout
.data
[5]),
1427 pktout
.data
+ 6, pktout
.length
- 6);
1430 * Compress packet payload.
1433 unsigned char *newpayload
;
1435 if (cscomp
&& cscomp
->compress(pktout
.data
+ 5, pktout
.length
- 5,
1436 &newpayload
, &newlen
)) {
1438 ssh2_pkt_adddata(newpayload
, newlen
);
1444 * Add padding. At least four bytes, and must also bring total
1445 * length (minus MAC) up to a multiple of the block size.
1447 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
1448 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1451 (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1452 maclen
= csmac ? csmac
->len
: 0;
1453 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
1454 pktout
.data
[4] = padding
;
1455 for (i
= 0; i
< padding
; i
++)
1456 pktout
.data
[pktout
.length
+ i
] = random_byte();
1457 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
1459 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
1461 outgoing_sequence
++; /* whether or not we MACed */
1464 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
1466 /* Ready-to-send packet starts at pktout.data. We return length. */
1467 return pktout
.length
+ padding
+ maclen
;
1471 * Construct and send an SSH2 packet immediately.
1473 static void ssh2_pkt_send(void)
1477 len
= ssh2_pkt_construct();
1478 backlog
= sk_write(s
, pktout
.data
, len
);
1479 if (backlog
> SSH_MAX_BACKLOG
)
1480 ssh_throttle_all(1, backlog
);
1484 * Construct an SSH2 packet and add it to a deferred data block.
1485 * Useful for sending multiple packets in a single sk_write() call,
1486 * to prevent a traffic-analysing listener from being able to work
1487 * out the length of any particular packet (such as the password
1490 * Note that because SSH2 sequence-numbers its packets, this can
1491 * NOT be used as an m4-style `defer' allowing packets to be
1492 * constructed in one order and sent in another.
1494 static void ssh2_pkt_defer(void)
1496 int len
= ssh2_pkt_construct();
1497 if (deferred_len
+ len
> deferred_size
) {
1498 deferred_size
= deferred_len
+ len
+ 128;
1499 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1501 memcpy(deferred_send_data
+ deferred_len
, pktout
.data
, len
);
1502 deferred_len
+= len
;
1506 * Send the whole deferred data block constructed by
1507 * ssh2_pkt_defer() or SSH1's defer_packet().
1509 static void ssh_pkt_defersend(void)
1512 backlog
= sk_write(s
, deferred_send_data
, deferred_len
);
1513 deferred_len
= deferred_size
= 0;
1514 sfree(deferred_send_data
);
1515 deferred_send_data
= NULL
;
1516 if (backlog
> SSH_MAX_BACKLOG
)
1517 ssh_throttle_all(1, backlog
);
1521 void bndebug(char *string
, Bignum b
)
1525 p
= ssh2_mpint_fmt(b
, &len
);
1526 debug(("%s", string
));
1527 for (i
= 0; i
< len
; i
++)
1528 debug((" %02x", p
[i
]));
1534 static void sha_mpint(SHA_State
* s
, Bignum b
)
1538 p
= ssh2_mpint_fmt(b
, &len
);
1539 sha_string(s
, p
, len
);
1544 * SSH2 packet decode functions.
1546 static unsigned long ssh2_pkt_getuint32(void)
1548 unsigned long value
;
1549 if (pktin
.length
- pktin
.savedpos
< 4)
1550 return 0; /* arrgh, no way to decline (FIXME?) */
1551 value
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1552 pktin
.savedpos
+= 4;
1555 static int ssh2_pkt_getbool(void)
1557 unsigned long value
;
1558 if (pktin
.length
- pktin
.savedpos
< 1)
1559 return 0; /* arrgh, no way to decline (FIXME?) */
1560 value
= pktin
.data
[pktin
.savedpos
] != 0;
1564 static void ssh2_pkt_getstring(char **p
, int *length
)
1568 if (pktin
.length
- pktin
.savedpos
< 4)
1570 *length
= GET_32BIT(pktin
.data
+ pktin
.savedpos
);
1571 pktin
.savedpos
+= 4;
1572 if (pktin
.length
- pktin
.savedpos
< *length
)
1574 *p
= pktin
.data
+ pktin
.savedpos
;
1575 pktin
.savedpos
+= *length
;
1577 static Bignum
ssh2_pkt_getmp(void)
1583 ssh2_pkt_getstring(&p
, &length
);
1587 bombout(("internal error: Can't handle negative mpints"));
1590 b
= bignum_from_bytes(p
, length
);
1595 * Helper function to add an SSH2 signature blob to a packet.
1596 * Expects to be shown the public key blob as well as the signature
1597 * blob. Normally works just like ssh2_pkt_addstring, but will
1598 * fiddle with the signature packet if necessary for
1599 * BUG_SSH2_RSA_PADDING.
1601 static void ssh2_add_sigblob(void *pkblob_v
, int pkblob_len
,
1602 void *sigblob_v
, int sigblob_len
)
1604 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1605 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1607 /* dmemdump(pkblob, pkblob_len); */
1608 /* dmemdump(sigblob, sigblob_len); */
1611 * See if this is in fact an ssh-rsa signature and a buggy
1612 * server; otherwise we can just do this the easy way.
1614 if ((ssh_remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1615 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1616 int pos
, len
, siglen
;
1619 * Find the byte length of the modulus.
1622 pos
= 4+7; /* skip over "ssh-rsa" */
1623 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1624 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1625 pos
+= 4; /* find modulus itself */
1626 while (len
> 0 && pkblob
[pos
] == 0)
1628 /* debug(("modulus length is %d\n", len)); */
1631 * Now find the signature integer.
1633 pos
= 4+7; /* skip over "ssh-rsa" */
1634 siglen
= GET_32BIT(sigblob
+pos
);
1635 /* debug(("signature length is %d\n", siglen)); */
1637 if (len
!= siglen
) {
1638 unsigned char newlen
[4];
1639 ssh2_pkt_addstring_start();
1640 ssh2_pkt_addstring_data(sigblob
, pos
);
1641 /* dmemdump(sigblob, pos); */
1642 pos
+= 4; /* point to start of actual sig */
1643 PUT_32BIT(newlen
, len
);
1644 ssh2_pkt_addstring_data(newlen
, 4);
1645 /* dmemdump(newlen, 4); */
1647 while (len
-- > siglen
) {
1648 ssh2_pkt_addstring_data(newlen
, 1);
1649 /* dmemdump(newlen, 1); */
1651 ssh2_pkt_addstring_data(sigblob
+pos
, siglen
);
1652 /* dmemdump(sigblob+pos, siglen); */
1656 /* Otherwise fall through and do it the easy way. */
1659 ssh2_pkt_addstring_start();
1660 ssh2_pkt_addstring_data(sigblob
, sigblob_len
);
1664 * Examine the remote side's version string and compare it against
1665 * a list of known buggy implementations.
1667 static void ssh_detect_bugs(char *vstring
)
1669 char *imp
; /* pointer to implementation part */
1671 imp
+= strcspn(imp
, "-");
1673 imp
+= strcspn(imp
, "-");
1676 ssh_remote_bugs
= 0;
1678 if (cfg
.sshbug_ignore1
== BUG_ON
||
1679 (cfg
.sshbug_ignore1
== BUG_AUTO
&&
1680 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1681 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1682 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")))) {
1684 * These versions don't support SSH1_MSG_IGNORE, so we have
1685 * to use a different defence against password length
1688 ssh_remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1689 logevent("We believe remote version has SSH1 ignore bug");
1692 if (cfg
.sshbug_plainpw1
== BUG_ON
||
1693 (cfg
.sshbug_plainpw1
== BUG_AUTO
&&
1694 (!strcmp(imp
, "Cisco-1.25")))) {
1696 * These versions need a plain password sent; they can't
1697 * handle having a null and a random length of data after
1700 ssh_remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1701 logevent("We believe remote version needs a plain SSH1 password");
1704 if (cfg
.sshbug_rsa1
== BUG_ON
||
1705 (cfg
.sshbug_rsa1
== BUG_AUTO
&&
1706 (!strcmp(imp
, "Cisco-1.25")))) {
1708 * These versions apparently have no clue whatever about
1709 * RSA authentication and will panic and die if they see
1710 * an AUTH_RSA message.
1712 ssh_remote_bugs
|= BUG_CHOKES_ON_RSA
;
1713 logevent("We believe remote version can't handle RSA authentication");
1716 if (cfg
.sshbug_hmac2
== BUG_ON
||
1717 (cfg
.sshbug_hmac2
== BUG_AUTO
&&
1718 (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1719 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1720 !strncmp(imp
, "2.1 ", 4)))) {
1722 * These versions have the HMAC bug.
1724 ssh_remote_bugs
|= BUG_SSH2_HMAC
;
1725 logevent("We believe remote version has SSH2 HMAC bug");
1728 if (cfg
.sshbug_derivekey2
== BUG_ON
||
1729 (cfg
.sshbug_derivekey2
== BUG_AUTO
&&
1730 (!strncmp(imp
, "2.0.", 4)))) {
1732 * These versions have the key-derivation bug (failing to
1733 * include the literal shared secret in the hashes that
1734 * generate the keys).
1736 ssh_remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1737 logevent("We believe remote version has SSH2 key-derivation bug");
1740 if (cfg
.sshbug_rsapad2
== BUG_ON
||
1741 (cfg
.sshbug_rsapad2
== BUG_AUTO
&&
1742 ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1743 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')))){
1745 * These versions have the SSH2 RSA padding bug.
1747 ssh_remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1748 logevent("We believe remote version has SSH2 RSA padding bug");
1751 if (cfg
.sshbug_dhgex2
== BUG_ON
) {
1753 * These versions have the SSH2 DH GEX bug.
1755 ssh_remote_bugs
|= BUG_SSH2_DH_GEX
;
1756 logevent("We believe remote version has SSH2 DH group exchange bug");
1760 static int do_ssh_init(unsigned char c
)
1763 static char version
[10];
1764 static char *vstring
;
1765 static int vstrsize
;
1768 static int proto1
, proto2
;
1772 /* Search for the string "SSH-" in the input. */
1775 static const int transS
[] = { 1, 2, 2, 1 };
1776 static const int transH
[] = { 0, 0, 3, 0 };
1777 static const int transminus
[] = { 0, 0, 0, -1 };
1788 crReturn(1); /* get another character */
1792 vstring
= smalloc(vstrsize
);
1793 strcpy(vstring
, "SSH-");
1797 crReturn(1); /* get another char */
1798 if (vslen
>= vstrsize
- 1) {
1800 vstring
= srealloc(vstring
, vstrsize
);
1802 vstring
[vslen
++] = c
;
1807 } else if (i
< sizeof(version
) - 1)
1809 } else if (c
== '\n')
1813 ssh_agentfwd_enabled
= FALSE
;
1814 rdpkt2_state
.incoming_sequence
= 0;
1817 vlog
= smalloc(20 + vslen
);
1818 vstring
[strcspn (vstring
, "\r\n")] = '\0'; /* remove end-of-line chars */
1819 sprintf(vlog
, "Server version: %s", vstring
);
1821 ssh_detect_bugs(vstring
);
1825 * Decide which SSH protocol version to support.
1828 /* Anything strictly below "2.0" means protocol 1 is supported. */
1829 proto1
= ssh_versioncmp(version
, "2.0") < 0;
1830 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1831 proto2
= ssh_versioncmp(version
, "1.99") >= 0;
1833 if (cfg
.sshprot
== 0 && !proto1
) {
1834 bombout(("SSH protocol version 1 required by user but not provided by server"));
1837 if (cfg
.sshprot
== 3 && !proto2
) {
1838 bombout(("SSH protocol version 2 required by user but not provided by server"));
1842 if (proto2
&& (cfg
.sshprot
>= 2 || !proto1
)) {
1846 char verstring
[80], vlog
[100];
1847 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1848 SHA_Init(&exhashbase
);
1850 * Hash our version string and their version string.
1852 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1853 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1854 sprintf(vlog
, "We claim version: %s", verstring
);
1856 strcat(verstring
, "\n");
1857 logevent("Using SSH protocol version 2");
1858 sk_write(s
, verstring
, strlen(verstring
));
1859 ssh_protocol
= ssh2_protocol
;
1861 s_rdpkt
= ssh2_rdpkt
;
1866 char verstring
[80], vlog
[100];
1867 sprintf(verstring
, "SSH-%s-%s",
1868 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"),
1870 sprintf(vlog
, "We claim version: %s", verstring
);
1872 strcat(verstring
, "\n");
1874 logevent("Using SSH protocol version 1");
1875 sk_write(s
, verstring
, strlen(verstring
));
1876 ssh_protocol
= ssh1_protocol
;
1878 s_rdpkt
= ssh1_rdpkt
;
1880 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1887 static void ssh_gotdata(unsigned char *data
, int datalen
)
1892 * To begin with, feed the characters one by one to the
1893 * protocol initialisation / selection function do_ssh_init().
1894 * When that returns 0, we're done with the initial greeting
1895 * exchange and can move on to packet discipline.
1900 crReturnV
; /* more data please */
1901 ret
= do_ssh_init(*data
);
1909 * We emerge from that loop when the initial negotiation is
1910 * over and we have selected an s_rdpkt function. Now pass
1911 * everything to s_rdpkt, and then pass the resulting packets
1912 * to the proper protocol handler.
1917 while (datalen
> 0) {
1918 if (s_rdpkt(&data
, &datalen
) == 0) {
1919 if (ssh_state
== SSH_STATE_CLOSED
) {
1922 ssh_protocol(NULL
, 0, 1);
1923 if (ssh_state
== SSH_STATE_CLOSED
) {
1933 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1936 ssh_state
= SSH_STATE_CLOSED
;
1942 /* A socket error has occurred. */
1943 logevent(error_msg
);
1944 connection_fatal(error_msg
);
1946 /* Otherwise, the remote side closed the connection normally. */
1951 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1953 ssh_gotdata(data
, len
);
1954 if (ssh_state
== SSH_STATE_CLOSED
) {
1964 static void ssh_sent(Plug plug
, int bufsize
)
1967 * If the send backlog on the SSH socket itself clears, we
1968 * should unthrottle the whole world if it was throttled.
1970 if (bufsize
< SSH_MAX_BACKLOG
)
1971 ssh_throttle_all(0, bufsize
);
1975 * Connect to specified host and port.
1976 * Returns an error message, or NULL on success.
1977 * Also places the canonical host name into `realhost'. It must be
1978 * freed by the caller.
1980 static char *connect_to_host(char *host
, int port
, char **realhost
, int nodelay
)
1982 static struct plug_function_table fn_table
= {
1987 }, *fn_table_ptr
= &fn_table
;
1996 savedhost
= smalloc(1 + strlen(host
));
1998 fatalbox("Out of memory");
1999 strcpy(savedhost
, host
);
2002 port
= 22; /* default ssh port */
2017 sprintf(buf
, "Looking up host \"%.170s\"", host
);
2020 addr
= sk_namelookup(host
, realhost
);
2021 if ((err
= sk_addr_error(addr
)))
2025 *realhost
= strdup(FWhost
);
2032 char buf
[200], addrbuf
[100];
2033 sk_getaddr(addr
, addrbuf
, 100);
2034 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
2037 s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, &fn_table_ptr
);
2038 if ((err
= sk_socket_error(s
))) {
2044 sk_write(s
, "connect ", 8);
2045 sk_write(s
, FWhost
, strlen(FWhost
));
2048 sprintf(buf
, " %d\n", FWport
);
2049 sk_write(s
, buf
, strlen(buf
));
2057 * Throttle or unthrottle the SSH connection.
2059 static void ssh1_throttle(int adjust
)
2061 int old_count
= ssh1_throttle_count
;
2062 ssh1_throttle_count
+= adjust
;
2063 assert(ssh1_throttle_count
>= 0);
2064 if (ssh1_throttle_count
&& !old_count
) {
2065 sk_set_frozen(s
, 1);
2066 } else if (!ssh1_throttle_count
&& old_count
) {
2067 sk_set_frozen(s
, 0);
2072 * Throttle or unthrottle _all_ local data streams (for when sends
2073 * on the SSH connection itself back up).
2075 static void ssh_throttle_all(int enable
, int bufsize
)
2078 struct ssh_channel
*c
;
2080 if (enable
== ssh_throttled_all
)
2082 ssh_throttled_all
= enable
;
2083 ssh_overall_bufsize
= bufsize
;
2086 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
2088 case CHAN_MAINSESSION
:
2090 * This is treated separately, outside the switch.
2094 x11_override_throttle(c
->u
.x11
.s
, enable
);
2097 /* Agent channels require no buffer management. */
2100 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2107 * Username and password input, abstracted off into reusable
2108 * routines (hopefully even reusable between SSH1 and SSH2!).
2110 static char *ssh_userpass_input_buffer
;
2111 static int ssh_userpass_input_buflen
;
2112 static int ssh_userpass_input_bufpos
;
2113 static int ssh_userpass_input_echo
;
2115 /* Set up a username or password input loop on a given buffer. */
2116 void setup_userpass_input(char *buffer
, int buflen
, int echo
)
2118 ssh_userpass_input_buffer
= buffer
;
2119 ssh_userpass_input_buflen
= buflen
;
2120 ssh_userpass_input_bufpos
= 0;
2121 ssh_userpass_input_echo
= echo
;
2125 * Process some terminal data in the course of username/password
2126 * input. Returns >0 for success (line of input returned in
2127 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2128 * for inconclusive (keep waiting for more input please).
2130 int process_userpass_input(unsigned char *in
, int inlen
)
2135 switch (c
= *in
++) {
2138 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
] = 0;
2139 ssh_userpass_input_buffer
[ssh_userpass_input_buflen
-1] = 0;
2144 if (ssh_userpass_input_bufpos
> 0) {
2145 if (ssh_userpass_input_echo
)
2146 c_write_str("\b \b");
2147 ssh_userpass_input_bufpos
--;
2152 while (ssh_userpass_input_bufpos
> 0) {
2153 if (ssh_userpass_input_echo
)
2154 c_write_str("\b \b");
2155 ssh_userpass_input_bufpos
--;
2163 if (((c
>= ' ' && c
<= '~') ||
2164 ((unsigned char) c
>= 160))
2165 && ssh_userpass_input_bufpos
< ssh_userpass_input_buflen
-1) {
2166 ssh_userpass_input_buffer
[ssh_userpass_input_bufpos
++] = c
;
2167 if (ssh_userpass_input_echo
)
2177 * Handle the key exchange and user authentication phases.
2179 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
2183 static unsigned char *rsabuf
, *keystr1
, *keystr2
;
2184 unsigned char cookie
[8];
2185 struct RSAKey servkey
, hostkey
;
2186 struct MD5Context md5c
;
2187 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
2188 static int tried_publickey
, tried_agent
;
2189 static int tis_auth_refused
, ccard_auth_refused
;
2190 static unsigned char session_id
[16];
2191 static int cipher_type
;
2192 static char username
[100];
2193 static void *publickey_blob
;
2194 int publickey_bloblen
;
2201 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2202 bombout(("Public key packet not received"));
2206 logevent("Received public keys");
2208 memcpy(cookie
, pktin
.body
, 8);
2210 i
= makekey(pktin
.body
+ 8, &servkey
, &keystr1
, 0);
2211 j
= makekey(pktin
.body
+ 8 + i
, &hostkey
, &keystr2
, 0);
2214 * Log the host key fingerprint.
2218 logevent("Host key fingerprint is:");
2219 strcpy(logmsg
, " ");
2220 hostkey
.comment
= NULL
;
2221 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2222 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2226 ssh1_remote_protoflags
= GET_32BIT(pktin
.body
+ 8 + i
+ j
);
2227 supported_ciphers_mask
= GET_32BIT(pktin
.body
+ 12 + i
+ j
);
2228 supported_auths_mask
= GET_32BIT(pktin
.body
+ 16 + i
+ j
);
2230 ssh1_local_protoflags
=
2231 ssh1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2232 ssh1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2235 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
2236 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
2237 MD5Update(&md5c
, pktin
.body
, 8);
2238 MD5Final(session_id
, &md5c
);
2240 for (i
= 0; i
< 32; i
++)
2241 session_key
[i
] = random_byte();
2243 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2245 rsabuf
= smalloc(len
);
2247 fatalbox("Out of memory");
2250 * Verify the host key.
2254 * First format the key into a string.
2256 int len
= rsastr_len(&hostkey
);
2257 char fingerprint
[100];
2258 char *keystr
= smalloc(len
);
2260 fatalbox("Out of memory");
2261 rsastr_fmt(keystr
, &hostkey
);
2262 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2263 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
,
2268 for (i
= 0; i
< 32; i
++) {
2269 rsabuf
[i
] = session_key
[i
];
2271 rsabuf
[i
] ^= session_id
[i
];
2274 if (hostkey
.bytes
> servkey
.bytes
) {
2275 rsaencrypt(rsabuf
, 32, &servkey
);
2276 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
2278 rsaencrypt(rsabuf
, 32, &hostkey
);
2279 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
2282 logevent("Encrypted session key");
2285 int cipher_chosen
= 0, warn
= 0;
2286 char *cipher_string
= NULL
;
2287 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2288 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2289 if (next_cipher
== CIPHER_WARN
) {
2290 /* If/when we choose a cipher, warn about it */
2292 } else if (next_cipher
== CIPHER_AES
) {
2293 /* XXX Probably don't need to mention this. */
2294 logevent("AES not supported in SSH1, skipping");
2296 switch (next_cipher
) {
2297 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
;
2298 cipher_string
= "3DES"; break;
2299 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
;
2300 cipher_string
= "Blowfish"; break;
2301 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
;
2302 cipher_string
= "single-DES"; break;
2304 if (supported_ciphers_mask
& (1 << cipher_type
))
2308 if (!cipher_chosen
) {
2309 if ((supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2310 bombout(("Server violates SSH 1 protocol by not "
2311 "supporting 3DES encryption"));
2313 /* shouldn't happen */
2314 bombout(("No supported ciphers found"));
2318 /* Warn about chosen cipher if necessary. */
2320 askcipher(cipher_string
, 0);
2323 switch (cipher_type
) {
2324 case SSH_CIPHER_3DES
:
2325 logevent("Using 3DES encryption");
2327 case SSH_CIPHER_DES
:
2328 logevent("Using single-DES encryption");
2330 case SSH_CIPHER_BLOWFISH
:
2331 logevent("Using Blowfish encryption");
2335 send_packet(SSH1_CMSG_SESSION_KEY
,
2336 PKT_CHAR
, cipher_type
,
2337 PKT_DATA
, cookie
, 8,
2338 PKT_CHAR
, (len
* 8) >> 8, PKT_CHAR
, (len
* 8) & 0xFF,
2339 PKT_DATA
, rsabuf
, len
,
2340 PKT_INT
, ssh1_local_protoflags
, PKT_END
);
2342 logevent("Trying to enable encryption...");
2346 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2347 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
: &ssh_3des
;
2348 cipher
->sesskey(session_key
);
2352 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2353 bombout(("Encryption not successfully enabled"));
2357 logevent("Successfully started encryption");
2361 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2362 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2363 if (!ssh_get_line("login as: ",
2364 username
, sizeof(username
), FALSE
)) {
2366 * get_line failed to get a username.
2369 logevent("No username provided. Abandoning session.");
2370 ssh_state
= SSH_STATE_CLOSED
;
2375 c_write_str("login as: ");
2378 setup_userpass_input(username
, sizeof(username
), 1);
2380 crWaitUntil(!ispkt
);
2381 ret
= process_userpass_input(in
, inlen
);
2385 c_write_str("\r\n");
2388 strncpy(username
, cfg
.username
, sizeof(username
));
2389 username
[sizeof(username
)-1] = '\0';
2392 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
2394 char userlog
[22 + sizeof(username
)];
2395 sprintf(userlog
, "Sent username \"%s\"", username
);
2397 if (flags
& FLAG_INTERACTIVE
&&
2398 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2399 strcat(userlog
, "\r\n");
2400 c_write_str(userlog
);
2407 if ((ssh_remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2408 /* We must not attempt PK auth. Pretend we've already tried it. */
2409 tried_publickey
= tried_agent
= 1;
2411 tried_publickey
= tried_agent
= 0;
2413 tis_auth_refused
= ccard_auth_refused
= 0;
2414 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2416 if (!rsakey_pubblob(cfg
.keyfile
, &publickey_blob
, &publickey_bloblen
))
2417 publickey_blob
= NULL
;
2419 publickey_blob
= NULL
;
2421 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
2422 static char password
[100];
2423 static char prompt
[200];
2426 static int pwpkt_type
;
2427 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2429 if (agent_exists() && !tried_agent
) {
2431 * Attempt RSA authentication using Pageant.
2433 static unsigned char request
[5], *response
, *p
;
2434 static int responselen
;
2435 static int i
, nkeys
;
2436 static int authed
= FALSE
;
2440 logevent("Pageant is running. Requesting keys.");
2442 /* Request the keys held by the agent. */
2443 PUT_32BIT(request
, 1);
2444 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2445 agent_query(request
, 5, &r
, &responselen
);
2446 response
= (unsigned char *) r
;
2447 if (response
&& responselen
>= 5 &&
2448 response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2450 nkeys
= GET_32BIT(p
);
2454 sprintf(buf
, "Pageant has %d SSH1 keys", nkeys
);
2457 for (i
= 0; i
< nkeys
; i
++) {
2458 static struct RSAKey key
;
2459 static Bignum challenge
;
2460 static char *commentp
;
2461 static int commentlen
;
2465 sprintf(buf
, "Trying Pageant key #%d", i
);
2468 if (publickey_blob
&&
2469 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
2470 logevent("This key matches configured key file");
2471 tried_publickey
= 1;
2474 p
+= ssh1_read_bignum(p
, &key
.exponent
);
2475 p
+= ssh1_read_bignum(p
, &key
.modulus
);
2476 commentlen
= GET_32BIT(p
);
2480 send_packet(SSH1_CMSG_AUTH_RSA
,
2481 PKT_BIGNUM
, key
.modulus
, PKT_END
);
2483 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2484 logevent("Key refused");
2487 logevent("Received RSA challenge");
2488 ssh1_read_bignum(pktin
.body
, &challenge
);
2490 char *agentreq
, *q
, *ret
;
2493 len
= 1 + 4; /* message type, bit count */
2494 len
+= ssh1_bignum_length(key
.exponent
);
2495 len
+= ssh1_bignum_length(key
.modulus
);
2496 len
+= ssh1_bignum_length(challenge
);
2497 len
+= 16; /* session id */
2498 len
+= 4; /* response format */
2499 agentreq
= smalloc(4 + len
);
2500 PUT_32BIT(agentreq
, len
);
2502 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2503 PUT_32BIT(q
, bignum_bitcount(key
.modulus
));
2505 q
+= ssh1_write_bignum(q
, key
.exponent
);
2506 q
+= ssh1_write_bignum(q
, key
.modulus
);
2507 q
+= ssh1_write_bignum(q
, challenge
);
2508 memcpy(q
, session_id
, 16);
2510 PUT_32BIT(q
, 1); /* response format */
2511 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2515 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2516 logevent("Sending Pageant's response");
2517 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2518 PKT_DATA
, ret
+ 5, 16,
2522 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2524 ("Pageant's response accepted");
2525 if (flags
& FLAG_VERBOSE
) {
2527 ("Authenticated using RSA key \"");
2528 c_write(commentp
, commentlen
);
2529 c_write_str("\" from agent\r\n");
2534 ("Pageant's response not accepted");
2537 ("Pageant failed to answer challenge");
2541 logevent("No reply received from Pageant");
2544 freebn(key
.exponent
);
2545 freebn(key
.modulus
);
2554 if (*cfg
.keyfile
&& !tried_publickey
)
2555 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2557 if (cfg
.try_tis_auth
&&
2558 (supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2559 !tis_auth_refused
) {
2560 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2561 logevent("Requested TIS authentication");
2562 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
2564 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2565 logevent("TIS authentication declined");
2566 if (flags
& FLAG_INTERACTIVE
)
2567 c_write_str("TIS authentication refused.\r\n");
2568 tis_auth_refused
= 1;
2571 int challengelen
= ((pktin
.body
[0] << 24) |
2572 (pktin
.body
[1] << 16) |
2573 (pktin
.body
[2] << 8) |
2575 logevent("Received TIS challenge");
2576 if (challengelen
> sizeof(prompt
) - 1)
2577 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2578 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2579 /* Prompt heuristic comes from OpenSSH */
2580 strncpy(prompt
+ challengelen
,
2581 memchr(prompt
, '\n', challengelen
) ?
2582 "": "\r\nResponse: ",
2583 (sizeof prompt
) - challengelen
);
2584 prompt
[(sizeof prompt
) - 1] = '\0';
2587 if (cfg
.try_tis_auth
&&
2588 (supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2589 !ccard_auth_refused
) {
2590 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2591 logevent("Requested CryptoCard authentication");
2592 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2594 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2595 logevent("CryptoCard authentication declined");
2596 c_write_str("CryptoCard authentication refused.\r\n");
2597 ccard_auth_refused
= 1;
2600 int challengelen
= ((pktin
.body
[0] << 24) |
2601 (pktin
.body
[1] << 16) |
2602 (pktin
.body
[2] << 8) |
2604 logevent("Received CryptoCard challenge");
2605 if (challengelen
> sizeof(prompt
) - 1)
2606 challengelen
= sizeof(prompt
) - 1; /* prevent overrun */
2607 memcpy(prompt
, pktin
.body
+ 4, challengelen
);
2608 strncpy(prompt
+ challengelen
,
2609 memchr(prompt
, '\n', challengelen
) ?
2610 "" : "\r\nResponse: ",
2611 sizeof(prompt
) - challengelen
);
2612 prompt
[sizeof(prompt
) - 1] = '\0';
2615 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2616 sprintf(prompt
, "%.90s@%.90s's password: ",
2617 username
, savedhost
);
2619 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2620 char *comment
= NULL
;
2623 if (flags
& FLAG_VERBOSE
)
2624 c_write_str("Trying public key authentication.\r\n");
2625 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2627 type
= key_type(cfg
.keyfile
);
2628 if (type
!= SSH_KEYTYPE_SSH1
) {
2629 sprintf(msgbuf
, "Key is of wrong type (%s)",
2630 key_type_to_str(type
));
2632 c_write_str(msgbuf
);
2633 c_write_str("\r\n");
2634 tried_publickey
= 1;
2637 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2638 if (flags
& FLAG_VERBOSE
)
2639 c_write_str("No passphrase required.\r\n");
2642 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
2647 * Show password prompt, having first obtained it via a TIS
2648 * or CryptoCard exchange if we're doing TIS or CryptoCard
2652 if (!ssh_get_line(prompt
, password
, sizeof(password
), TRUE
)) {
2654 * get_line failed to get a password (for example
2655 * because one was supplied on the command line
2656 * which has already failed to work). Terminate.
2658 send_packet(SSH1_MSG_DISCONNECT
,
2659 PKT_STR
, "No more passwords available to try",
2661 logevent("Unable to authenticate");
2662 connection_fatal("Unable to authenticate");
2663 ssh_state
= SSH_STATE_CLOSED
;
2667 /* Prompt may have come from server. We've munged it a bit, so
2668 * we know it to be zero-terminated at least once. */
2670 c_write_untrusted(prompt
, strlen(prompt
));
2673 setup_userpass_input(password
, sizeof(password
), 0);
2675 crWaitUntil(!ispkt
);
2676 ret
= process_userpass_input(in
, inlen
);
2680 c_write_str("\r\n");
2684 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2686 * Try public key authentication with the specified
2689 static struct RSAKey pubkey
;
2690 static Bignum challenge
, response
;
2692 static unsigned char buffer
[32];
2694 tried_publickey
= 1;
2695 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
2697 c_write_str("Couldn't load private key from ");
2698 c_write_str(cfg
.keyfile
);
2699 c_write_str(".\r\n");
2700 continue; /* go and try password */
2703 c_write_str("Wrong passphrase.\r\n");
2704 tried_publickey
= 0;
2705 continue; /* try again */
2709 * Send a public key attempt.
2711 send_packet(SSH1_CMSG_AUTH_RSA
,
2712 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
2715 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2716 c_write_str("Server refused our public key.\r\n");
2717 continue; /* go and try password */
2719 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2720 bombout(("Bizarre response to offer of public key"));
2723 ssh1_read_bignum(pktin
.body
, &challenge
);
2724 response
= rsadecrypt(challenge
, &pubkey
);
2725 freebn(pubkey
.private_exponent
); /* burn the evidence */
2727 for (i
= 0; i
< 32; i
++) {
2728 buffer
[i
] = bignum_byte(response
, 31 - i
);
2732 MD5Update(&md5c
, buffer
, 32);
2733 MD5Update(&md5c
, session_id
, 16);
2734 MD5Final(buffer
, &md5c
);
2736 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
2737 PKT_DATA
, buffer
, 16, PKT_END
);
2740 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2741 if (flags
& FLAG_VERBOSE
)
2743 ("Failed to authenticate with our public key.\r\n");
2744 continue; /* go and try password */
2745 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2747 ("Bizarre response to RSA authentication response"));
2751 break; /* we're through! */
2753 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2755 * Defence against traffic analysis: we send a
2756 * whole bunch of packets containing strings of
2757 * different lengths. One of these strings is the
2758 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2759 * The others are all random data in
2760 * SSH1_MSG_IGNORE packets. This way a passive
2761 * listener can't tell which is the password, and
2762 * hence can't deduce the password length.
2764 * Anybody with a password length greater than 16
2765 * bytes is going to have enough entropy in their
2766 * password that a listener won't find it _that_
2767 * much help to know how long it is. So what we'll
2770 * - if password length < 16, we send 15 packets
2771 * containing string lengths 1 through 15
2773 * - otherwise, we let N be the nearest multiple
2774 * of 8 below the password length, and send 8
2775 * packets containing string lengths N through
2776 * N+7. This won't obscure the order of
2777 * magnitude of the password length, but it will
2778 * introduce a bit of extra uncertainty.
2780 * A few servers (the old 1.2.18 through 1.2.22)
2781 * can't deal with SSH1_MSG_IGNORE. For these
2782 * servers, we need an alternative defence. We make
2783 * use of the fact that the password is interpreted
2784 * as a C string: so we can append a NUL, then some
2787 * One server (a Cisco one) can deal with neither
2788 * SSH1_MSG_IGNORE _nor_ a padded password string.
2789 * For this server we are left with no defences
2790 * against password length sniffing.
2792 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2794 * The server can deal with SSH1_MSG_IGNORE, so
2795 * we can use the primary defence.
2797 int bottom
, top
, pwlen
, i
;
2800 pwlen
= strlen(password
);
2802 bottom
= 0; /* zero length passwords are OK! :-) */
2805 bottom
= pwlen
& ~7;
2809 assert(pwlen
>= bottom
&& pwlen
<= top
);
2811 randomstr
= smalloc(top
+ 1);
2813 for (i
= bottom
; i
<= top
; i
++) {
2815 defer_packet(pwpkt_type
, PKT_STR
, password
,
2818 for (j
= 0; j
< i
; j
++) {
2820 randomstr
[j
] = random_byte();
2821 } while (randomstr
[j
] == '\0');
2823 randomstr
[i
] = '\0';
2824 defer_packet(SSH1_MSG_IGNORE
,
2825 PKT_STR
, randomstr
, PKT_END
);
2828 logevent("Sending password with camouflage packets");
2829 ssh_pkt_defersend();
2831 else if (!(ssh_remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2833 * The server can't deal with SSH1_MSG_IGNORE
2834 * but can deal with padded passwords, so we
2835 * can use the secondary defence.
2841 len
= strlen(password
);
2842 if (len
< sizeof(string
)) {
2844 strcpy(string
, password
);
2845 len
++; /* cover the zero byte */
2846 while (len
< sizeof(string
)) {
2847 string
[len
++] = (char) random_byte();
2852 logevent("Sending length-padded password");
2853 send_packet(pwpkt_type
, PKT_INT
, len
,
2854 PKT_DATA
, s
, len
, PKT_END
);
2857 * The server has _both_
2858 * BUG_CHOKES_ON_SSH1_IGNORE and
2859 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2860 * therefore nothing we can do.
2863 len
= strlen(password
);
2864 logevent("Sending unpadded password");
2865 send_packet(pwpkt_type
, PKT_INT
, len
,
2866 PKT_DATA
, password
, len
, PKT_END
);
2869 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
2872 logevent("Sent password");
2873 memset(password
, 0, strlen(password
));
2875 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2876 if (flags
& FLAG_VERBOSE
)
2877 c_write_str("Access denied\r\n");
2878 logevent("Authentication refused");
2879 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2880 logevent("Received disconnect request");
2881 ssh_state
= SSH_STATE_CLOSED
;
2883 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2884 bombout(("Strange packet received, type %d", pktin
.type
));
2889 logevent("Authentication successful");
2894 void sshfwd_close(struct ssh_channel
*c
)
2896 if (c
&& !c
->closes
) {
2898 * If the channel's remoteid is -1, we have sent
2899 * CHANNEL_OPEN for this channel, but it hasn't even been
2900 * acknowledged by the server. So we must set a close flag
2901 * on it now, and then when the server acks the channel
2902 * open, we can close it then.
2904 if (((int)c
->remoteid
) != -1) {
2905 if (ssh_version
== 1) {
2906 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2909 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2910 ssh2_pkt_adduint32(c
->remoteid
);
2914 c
->closes
= 1; /* sent MSG_CLOSE */
2915 if (c
->type
== CHAN_X11
) {
2917 logevent("Forwarded X11 connection terminated");
2918 } else if (c
->type
== CHAN_SOCKDATA
||
2919 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2921 logevent("Forwarded port closed");
2926 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2928 if (ssh_version
== 1) {
2929 send_packet(SSH1_MSG_CHANNEL_DATA
,
2930 PKT_INT
, c
->remoteid
,
2931 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2933 * In SSH1 we can return 0 here - implying that forwarded
2934 * connections are never individually throttled - because
2935 * the only circumstance that can cause throttling will be
2936 * the whole SSH connection backing up, in which case
2937 * _everything_ will be throttled as a whole.
2941 ssh2_add_channel_data(c
, buf
, len
);
2942 return ssh2_try_send(c
);
2946 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2948 if (ssh_version
== 1) {
2949 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2950 c
->v
.v1
.throttling
= 0;
2954 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
2958 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
)
2964 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
2967 if (ssh_state
== SSH_STATE_CLOSED
)
2970 if (cfg
.agentfwd
&& agent_exists()) {
2971 logevent("Requesting agent forwarding");
2972 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
2976 if (pktin
.type
!= SSH1_SMSG_SUCCESS
2977 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
2978 bombout(("Protocol confusion"));
2980 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2981 logevent("Agent forwarding refused");
2983 logevent("Agent forwarding enabled");
2984 ssh_agentfwd_enabled
= TRUE
;
2988 if (cfg
.x11_forward
) {
2989 char proto
[20], data
[64];
2990 logevent("Requesting X11 forwarding");
2991 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2992 if (ssh1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
2993 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2994 PKT_STR
, proto
, PKT_STR
, data
,
2995 PKT_INT
, 0, PKT_END
);
2997 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2998 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3003 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3004 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3005 bombout(("Protocol confusion"));
3007 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3008 logevent("X11 forwarding refused");
3010 logevent("X11 forwarding enabled");
3011 ssh_X11_fwd_enabled
= TRUE
;
3019 int sport
,dport
,sserv
,dserv
;
3020 char sports
[256], dports
[256], host
[256];
3024 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3025 /* Add port forwardings. */
3030 while (*e
&& *e
!= '\t')
3036 while (*e
&& *e
!= ':')
3046 dport
= atoi(dports
);
3050 se
= getservbyname(dports
, NULL
);
3052 dport
= ntohs(se
->s_port
);
3055 "Service lookup failed for destination port \"%s\"",
3060 sport
= atoi(sports
);
3064 se
= getservbyname(sports
, NULL
);
3066 sport
= ntohs(se
->s_port
);
3069 "Service lookup failed for source port \"%s\"",
3074 if (sport
&& dport
) {
3076 pfd_addforward(host
, dport
, sport
);
3077 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3078 " %s:%.*s%.*s%d%.*s",
3079 sserv ?
strlen(sports
) : 0, sports
,
3080 sserv
, "(", sport
, sserv
, ")",
3082 dserv ?
strlen(dports
) : 0, dports
,
3083 dserv
, "(", dport
, dserv
, ")");
3086 struct ssh_rportfwd
*pf
;
3087 pf
= smalloc(sizeof(*pf
));
3088 strcpy(pf
->dhost
, host
);
3090 if (add234(ssh_rportfwds
, pf
) != pf
) {
3092 "Duplicate remote port forwarding to %s:%d",
3097 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3098 " forward to %s:%.*s%.*s%d%.*s",
3099 sserv ?
strlen(sports
) : 0, sports
,
3100 sserv
, "(", sport
, sserv
, ")",
3102 dserv ?
strlen(dports
) : 0, dports
,
3103 dserv
, "(", dport
, dserv
, ")");
3105 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST
,
3113 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3114 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3115 bombout(("Protocol confusion"));
3117 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3118 c_write_str("Server refused port forwarding\r\n");
3119 ssh_editing
= ssh_echoing
= 1;
3121 logevent("Remote port forwarding enabled");
3129 send_packet(SSH1_CMSG_REQUEST_PTY
,
3130 PKT_STR
, cfg
.termtype
,
3131 PKT_INT
, ssh_term_height
,
3132 PKT_INT
, ssh_term_width
,
3133 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3134 ssh_state
= SSH_STATE_INTERMED
;
3138 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3139 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3140 bombout(("Protocol confusion"));
3142 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3143 c_write_str("Server refused to allocate pty\r\n");
3144 ssh_editing
= ssh_echoing
= 1;
3146 logevent("Allocated pty");
3148 ssh_editing
= ssh_echoing
= 1;
3151 if (cfg
.compression
) {
3152 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3156 if (pktin
.type
!= SSH1_SMSG_SUCCESS
3157 && pktin
.type
!= SSH1_SMSG_FAILURE
) {
3158 bombout(("Protocol confusion"));
3160 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3161 c_write_str("Server refused to compress\r\n");
3163 logevent("Started compression");
3164 ssh1_compressing
= TRUE
;
3165 zlib_compress_init();
3166 zlib_decompress_init();
3170 * Start the shell or command.
3172 * Special case: if the first-choice command is an SSH2
3173 * subsystem (hence not usable here) and the second choice
3174 * exists, we fall straight back to that.
3177 char *cmd
= cfg
.remote_cmd_ptr
;
3179 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3180 cmd
= cfg
.remote_cmd_ptr2
;
3181 ssh_fallback_cmd
= TRUE
;
3184 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3186 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3187 logevent("Started session");
3190 ssh_state
= SSH_STATE_SESSION
;
3192 ssh_size(ssh_term_width
, ssh_term_height
);
3194 ssh_special(TS_EOF
);
3196 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
3198 ssh_channels
= newtree234(ssh_channelcmp
);
3202 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3203 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3204 long len
= GET_32BIT(pktin
.body
);
3206 from_backend(frontend
, pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3207 pktin
.body
+ 4, len
);
3208 if (!ssh1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3209 ssh1_stdout_throttling
= 1;
3212 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
3213 ssh_state
= SSH_STATE_CLOSED
;
3214 logevent("Received disconnect request");
3216 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3217 /* Remote side is trying to open a channel to talk to our
3218 * X-Server. Give them back a local channel number. */
3219 struct ssh_channel
*c
;
3221 logevent("Received X11 connect request");
3222 /* Refuse if X11 forwarding is disabled. */
3223 if (!ssh_X11_fwd_enabled
) {
3224 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3225 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3226 logevent("Rejected X11 connect request");
3228 c
= smalloc(sizeof(struct ssh_channel
));
3230 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3231 logevent("opening X11 forward connection failed");
3233 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3234 PKT_INT
, GET_32BIT(pktin
.body
),
3238 ("opening X11 forward connection succeeded");
3239 c
->remoteid
= GET_32BIT(pktin
.body
);
3240 c
->localid
= alloc_channel_id();
3242 c
->v
.v1
.throttling
= 0;
3243 c
->type
= CHAN_X11
; /* identify channel type */
3244 add234(ssh_channels
, c
);
3245 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3246 PKT_INT
, c
->remoteid
, PKT_INT
,
3247 c
->localid
, PKT_END
);
3248 logevent("Opened X11 forward channel");
3251 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3252 /* Remote side is trying to open a channel to talk to our
3253 * agent. Give them back a local channel number. */
3254 struct ssh_channel
*c
;
3256 /* Refuse if agent forwarding is disabled. */
3257 if (!ssh_agentfwd_enabled
) {
3258 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3259 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3261 c
= smalloc(sizeof(struct ssh_channel
));
3262 c
->remoteid
= GET_32BIT(pktin
.body
);
3263 c
->localid
= alloc_channel_id();
3265 c
->v
.v1
.throttling
= 0;
3266 c
->type
= CHAN_AGENT
; /* identify channel type */
3267 c
->u
.a
.lensofar
= 0;
3268 add234(ssh_channels
, c
);
3269 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3270 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3273 } else if (pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3274 /* Remote side is trying to open a channel to talk to a
3275 * forwarded port. Give them back a local channel number. */
3276 struct ssh_channel
*c
;
3277 struct ssh_rportfwd pf
;
3279 char host
[256], buf
[1024];
3281 c
= smalloc(sizeof(struct ssh_channel
));
3283 hostsize
= GET_32BIT(pktin
.body
+4);
3284 for(h
= host
, p
= pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3285 if (h
+1 < host
+sizeof(host
))
3290 port
= GET_32BIT(p
);
3292 strcpy(pf
.dhost
, host
);
3295 if (find234(ssh_rportfwds
, &pf
, NULL
) == NULL
) {
3296 sprintf(buf
, "Rejected remote port open request for %s:%d",
3299 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3300 PKT_INT
, GET_32BIT(pktin
.body
), PKT_END
);
3302 sprintf(buf
, "Received remote port open request for %s:%d",
3305 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3308 sprintf(buf
, "Port open failed: %s", e
);
3311 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3312 PKT_INT
, GET_32BIT(pktin
.body
),
3315 c
->remoteid
= GET_32BIT(pktin
.body
);
3316 c
->localid
= alloc_channel_id();
3318 c
->v
.v1
.throttling
= 0;
3319 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3320 add234(ssh_channels
, c
);
3321 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3322 PKT_INT
, c
->remoteid
, PKT_INT
,
3323 c
->localid
, PKT_END
);
3324 logevent("Forwarded port opened successfully");
3328 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3329 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3330 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3331 struct ssh_channel
*c
;
3333 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3334 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3335 c
->remoteid
= localid
;
3336 c
->type
= CHAN_SOCKDATA
;
3337 c
->v
.v1
.throttling
= 0;
3338 pfd_confirm(c
->u
.pfd
.s
);
3341 if (c
&& c
->closes
) {
3343 * We have a pending close on this channel,
3344 * which we decided on before the server acked
3345 * the channel open. So now we know the
3346 * remoteid, we can close it again.
3348 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3352 } else if (pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3353 unsigned int remoteid
= GET_32BIT(pktin
.body
);
3354 unsigned int localid
= GET_32BIT(pktin
.body
+4);
3355 struct ssh_channel
*c
;
3357 c
= find234(ssh_channels
, &remoteid
, ssh_channelfind
);
3358 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3359 logevent("Forwarded connection refused by server");
3360 pfd_close(c
->u
.pfd
.s
);
3361 del234(ssh_channels
, c
);
3365 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3366 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3367 /* Remote side closes a channel. */
3368 unsigned i
= GET_32BIT(pktin
.body
);
3369 struct ssh_channel
*c
;
3370 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3371 if (c
&& ((int)c
->remoteid
) != -1) {
3374 (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3376 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3377 logevent("Forwarded X11 connection terminated");
3378 assert(c
->u
.x11
.s
!= NULL
);
3379 x11_close(c
->u
.x11
.s
);
3382 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3383 logevent("Forwarded port closed");
3384 assert(c
->u
.pfd
.s
!= NULL
);
3385 pfd_close(c
->u
.pfd
.s
);
3389 c
->closes
|= (closetype
<< 2); /* seen this message */
3390 if (!(c
->closes
& closetype
)) {
3391 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
,
3393 c
->closes
|= closetype
; /* sent it too */
3396 if (c
->closes
== 15) {
3397 del234(ssh_channels
, c
);
3401 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3402 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3403 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3406 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3407 /* Data sent down one of our channels. */
3408 int i
= GET_32BIT(pktin
.body
);
3409 int len
= GET_32BIT(pktin
.body
+ 4);
3410 unsigned char *p
= pktin
.body
+ 8;
3411 struct ssh_channel
*c
;
3412 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3417 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3420 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3423 /* Data for an agent message. Buffer it. */
3425 if (c
->u
.a
.lensofar
< 4) {
3426 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3427 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3431 c
->u
.a
.lensofar
+= l
;
3433 if (c
->u
.a
.lensofar
== 4) {
3435 4 + GET_32BIT(c
->u
.a
.msglen
);
3436 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3437 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3439 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3441 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3443 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3447 c
->u
.a
.lensofar
+= l
;
3449 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3450 void *reply
, *sentreply
;
3452 agent_query(c
->u
.a
.message
,
3453 c
->u
.a
.totallen
, &reply
,
3458 /* Fake SSH_AGENT_FAILURE. */
3459 sentreply
= "\0\0\0\1\5";
3462 send_packet(SSH1_MSG_CHANNEL_DATA
,
3463 PKT_INT
, c
->remoteid
,
3465 PKT_DATA
, sentreply
, replylen
,
3469 sfree(c
->u
.a
.message
);
3470 c
->u
.a
.lensofar
= 0;
3473 bufsize
= 0; /* agent channels never back up */
3476 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3477 c
->v
.v1
.throttling
= 1;
3481 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
3482 /* may be from EXEC_SHELL on some servers */
3483 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
3484 /* may be from EXEC_SHELL on some servers
3485 * if no pty is available or in other odd cases. Ignore */
3486 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3488 ssh_exitcode
= GET_32BIT(pktin
.body
);
3489 sprintf(buf
, "Server sent command exit status %d",
3492 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3494 * In case `helpful' firewalls or proxies tack
3495 * extra human-readable text on the end of the
3496 * session which we might mistake for another
3497 * encrypted packet, we close the session once
3498 * we've sent EXIT_CONFIRMATION.
3500 ssh_state
= SSH_STATE_CLOSED
;
3503 bombout(("Strange packet received: type %d", pktin
.type
));
3508 int len
= min(inlen
, 512);
3509 send_packet(SSH1_CMSG_STDIN_DATA
,
3510 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3521 * Utility routine for decoding comma-separated strings in KEXINIT.
3523 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3525 int needlen
= strlen(needle
);
3528 * Is it at the start of the string?
3530 if (haylen
>= needlen
&& /* haystack is long enough */
3531 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3532 (haylen
== needlen
|| haystack
[needlen
] == ',')
3533 /* either , or EOS follows */
3537 * If not, search for the next comma and resume after that.
3538 * If no comma found, terminate.
3540 while (haylen
> 0 && *haystack
!= ',')
3541 haylen
--, haystack
++;
3544 haylen
--, haystack
++; /* skip over comma itself */
3549 * SSH2 key creation method.
3551 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
,
3555 /* First 20 bytes. */
3557 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3559 SHA_Bytes(&s
, H
, 20);
3560 SHA_Bytes(&s
, &chr
, 1);
3561 SHA_Bytes(&s
, sessid
, 20);
3562 SHA_Final(&s
, keyspace
);
3563 /* Next 20 bytes. */
3565 if (!(ssh_remote_bugs
& BUG_SSH2_DERIVEKEY
))
3567 SHA_Bytes(&s
, H
, 20);
3568 SHA_Bytes(&s
, keyspace
, 20);
3569 SHA_Final(&s
, keyspace
+ 20);
3573 * Handle the SSH2 transport layer.
3575 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
3577 static int i
, j
, len
, nbits
, pbits
, warn
;
3579 static Bignum p
, g
, e
, f
, K
;
3580 static int kex_init_value
, kex_reply_value
;
3581 static const struct ssh_mac
**maclist
;
3583 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
3584 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
3585 static const struct ssh_mac
*csmac_tobe
= NULL
;
3586 static const struct ssh_mac
*scmac_tobe
= NULL
;
3587 static const struct ssh_compress
*cscomp_tobe
= NULL
;
3588 static const struct ssh_compress
*sccomp_tobe
= NULL
;
3589 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3590 static int hostkeylen
, siglen
;
3591 static void *hkey
; /* actual host key */
3592 static unsigned char exchange_hash
[20];
3593 static unsigned char keyspace
[40];
3594 static int n_preferred_ciphers
;
3595 static const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3596 static const struct ssh_compress
*preferred_comp
;
3597 static int cipherstr_started
;
3598 static int first_kex
;
3605 * Set up the preferred ciphers. (NULL => warn below here)
3607 n_preferred_ciphers
= 0;
3608 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3609 switch (cfg
.ssh_cipherlist
[i
]) {
3610 case CIPHER_BLOWFISH
:
3611 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_blowfish
;
3612 n_preferred_ciphers
++;
3615 if (cfg
.ssh2_des_cbc
) {
3616 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_des
;
3617 n_preferred_ciphers
++;
3621 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_3des
;
3622 n_preferred_ciphers
++;
3625 preferred_ciphers
[n_preferred_ciphers
] = &ssh2_aes
;
3626 n_preferred_ciphers
++;
3629 /* Flag for later. Don't bother if it's the last in
3631 if (i
< CIPHER_MAX
- 1) {
3632 preferred_ciphers
[n_preferred_ciphers
] = NULL
;
3633 n_preferred_ciphers
++;
3640 * Set up preferred compression.
3642 if (cfg
.compression
)
3643 preferred_comp
= &ssh_zlib
;
3645 preferred_comp
= &ssh_comp_none
;
3648 * Be prepared to work around the buggy MAC problem.
3650 if (ssh_remote_bugs
& BUG_SSH2_HMAC
)
3651 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
3653 maclist
= macs
, nmacs
= lenof(macs
);
3657 * Construct and send our key exchange packet.
3659 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
3660 for (i
= 0; i
< 16; i
++)
3661 ssh2_pkt_addbyte((unsigned char) random_byte());
3662 /* List key exchange algorithms. */
3663 ssh2_pkt_addstring_start();
3664 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3665 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3666 (ssh_remote_bugs
& BUG_SSH2_DH_GEX
))
3668 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
3669 if (i
< lenof(kex_algs
) - 1)
3670 ssh2_pkt_addstring_str(",");
3672 /* List server host key algorithms. */
3673 ssh2_pkt_addstring_start();
3674 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3675 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
3676 if (i
< lenof(hostkey_algs
) - 1)
3677 ssh2_pkt_addstring_str(",");
3679 /* List client->server encryption algorithms. */
3680 ssh2_pkt_addstring_start();
3681 cipherstr_started
= 0;
3682 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3683 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3684 if (!c
) continue; /* warning flag */
3685 for (j
= 0; j
< c
->nciphers
; j
++) {
3686 if (cipherstr_started
)
3687 ssh2_pkt_addstring_str(",");
3688 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3689 cipherstr_started
= 1;
3692 /* List server->client encryption algorithms. */
3693 ssh2_pkt_addstring_start();
3694 cipherstr_started
= 0;
3695 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3696 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3697 if (!c
) continue; /* warning flag */
3698 for (j
= 0; j
< c
->nciphers
; j
++) {
3699 if (cipherstr_started
)
3700 ssh2_pkt_addstring_str(",");
3701 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
3702 cipherstr_started
= 1;
3705 /* List client->server MAC algorithms. */
3706 ssh2_pkt_addstring_start();
3707 for (i
= 0; i
< nmacs
; i
++) {
3708 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3710 ssh2_pkt_addstring_str(",");
3712 /* List server->client MAC algorithms. */
3713 ssh2_pkt_addstring_start();
3714 for (i
= 0; i
< nmacs
; i
++) {
3715 ssh2_pkt_addstring_str(maclist
[i
]->name
);
3717 ssh2_pkt_addstring_str(",");
3719 /* List client->server compression algorithms. */
3720 ssh2_pkt_addstring_start();
3721 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3722 const struct ssh_compress
*c
=
3723 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3724 ssh2_pkt_addstring_str(c
->name
);
3725 if (i
< lenof(compressions
))
3726 ssh2_pkt_addstring_str(",");
3728 /* List server->client compression algorithms. */
3729 ssh2_pkt_addstring_start();
3730 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3731 const struct ssh_compress
*c
=
3732 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3733 ssh2_pkt_addstring_str(c
->name
);
3734 if (i
< lenof(compressions
))
3735 ssh2_pkt_addstring_str(",");
3737 /* List client->server languages. Empty list. */
3738 ssh2_pkt_addstring_start();
3739 /* List server->client languages. Empty list. */
3740 ssh2_pkt_addstring_start();
3741 /* First KEX packet does _not_ follow, because we're not that brave. */
3742 ssh2_pkt_addbool(FALSE
);
3744 ssh2_pkt_adduint32(0);
3746 exhash
= exhashbase
;
3747 sha_string(&exhash
, pktout
.data
+ 5, pktout
.length
- 5);
3753 sha_string(&exhash
, pktin
.data
+ 5, pktin
.length
- 5);
3756 * Now examine the other side's KEXINIT to see what we're up
3759 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
3760 bombout(("expected key exchange packet from server"));
3765 cscipher_tobe
= NULL
;
3766 sccipher_tobe
= NULL
;
3771 pktin
.savedpos
+= 16; /* skip garbage cookie */
3772 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
3773 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3774 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3775 (ssh_remote_bugs
& BUG_SSH2_DH_GEX
))
3777 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3782 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
3783 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3784 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3785 hostkey
= hostkey_algs
[i
];
3789 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
3791 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3792 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3796 for (j
= 0; j
< c
->nciphers
; j
++) {
3797 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3798 cscipher_tobe
= c
->list
[j
];
3803 if (cscipher_tobe
) {
3805 askcipher(cscipher_tobe
->name
, 1);
3809 if (!cscipher_tobe
) {
3810 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3814 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
3816 for (i
= 0; i
< n_preferred_ciphers
; i
++) {
3817 const struct ssh2_ciphers
*c
= preferred_ciphers
[i
];
3821 for (j
= 0; j
< c
->nciphers
; j
++) {
3822 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3823 sccipher_tobe
= c
->list
[j
];
3828 if (sccipher_tobe
) {
3830 askcipher(sccipher_tobe
->name
, 2);
3834 if (!sccipher_tobe
) {
3835 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3839 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
3840 for (i
= 0; i
< nmacs
; i
++) {
3841 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3842 csmac_tobe
= maclist
[i
];
3846 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
3847 for (i
= 0; i
< nmacs
; i
++) {
3848 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
3849 scmac_tobe
= maclist
[i
];
3853 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
3854 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3855 const struct ssh_compress
*c
=
3856 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3857 if (in_commasep_string(c
->name
, str
, len
)) {
3862 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
3863 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3864 const struct ssh_compress
*c
=
3865 i
== 0 ? preferred_comp
: compressions
[i
- 1];
3866 if (in_commasep_string(c
->name
, str
, len
)) {
3873 * Work out the number of bits of key we will need from the key
3874 * exchange. We start with the maximum key length of either
3880 csbits
= cscipher_tobe
->keylen
;
3881 scbits
= sccipher_tobe
->keylen
;
3882 nbits
= (csbits
> scbits ? csbits
: scbits
);
3884 /* The keys only have 160-bit entropy, since they're based on
3885 * a SHA-1 hash. So cap the key size at 160 bits. */
3890 * If we're doing Diffie-Hellman group exchange, start by
3891 * requesting a group.
3893 if (kex
== &ssh_diffiehellman_gex
) {
3894 logevent("Doing Diffie-Hellman group exchange");
3895 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3897 * Work out how big a DH group we will need to allow that
3900 pbits
= 512 << ((nbits
- 1) / 64);
3901 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
3902 ssh2_pkt_adduint32(pbits
);
3906 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3907 bombout(("expected key exchange group packet from server"));
3910 p
= ssh2_pkt_getmp();
3911 g
= ssh2_pkt_getmp();
3912 dh_setup_group(p
, g
);
3913 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3914 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3916 ssh_pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3918 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3919 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3922 logevent("Doing Diffie-Hellman key exchange");
3924 * Now generate and send e for Diffie-Hellman.
3926 e
= dh_create_e(nbits
* 2);
3927 ssh2_pkt_init(kex_init_value
);
3932 if (pktin
.type
!= kex_reply_value
) {
3933 bombout(("expected key exchange reply packet from server"));
3936 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
3937 f
= ssh2_pkt_getmp();
3938 ssh2_pkt_getstring(&sigdata
, &siglen
);
3942 sha_string(&exhash
, hostkeydata
, hostkeylen
);
3943 if (kex
== &ssh_diffiehellman_gex
) {
3944 sha_uint32(&exhash
, pbits
);
3945 sha_mpint(&exhash
, p
);
3946 sha_mpint(&exhash
, g
);
3948 sha_mpint(&exhash
, e
);
3949 sha_mpint(&exhash
, f
);
3950 sha_mpint(&exhash
, K
);
3951 SHA_Final(&exhash
, exchange_hash
);
3956 debug(("Exchange hash is:\n"));
3957 dmemdump(exchange_hash
, 20);
3960 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
3962 !hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
3963 bombout(("Server's host key did not match the signature supplied"));
3968 * Authenticate remote host: verify host key. (We've already
3969 * checked the signature of the exchange hash.)
3971 keystr
= hostkey
->fmtkey(hkey
);
3972 fingerprint
= hostkey
->fingerprint(hkey
);
3973 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
3974 keystr
, fingerprint
);
3975 if (first_kex
) { /* don't bother logging this in rekeys */
3976 logevent("Host key fingerprint is:");
3977 logevent(fingerprint
);
3981 hostkey
->freekey(hkey
);
3984 * Send SSH2_MSG_NEWKEYS.
3986 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
3990 * Expect SSH2_MSG_NEWKEYS from server.
3993 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
3994 bombout(("expected new-keys packet from server"));
3999 * Create and initialise session keys.
4001 cscipher
= cscipher_tobe
;
4002 sccipher
= sccipher_tobe
;
4005 cscomp
= cscomp_tobe
;
4006 sccomp
= sccomp_tobe
;
4007 cscomp
->compress_init();
4008 sccomp
->decompress_init();
4010 * Set IVs after keys. Here we use the exchange hash from the
4011 * _first_ key exchange.
4014 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
4015 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
4016 cscipher
->setcskey(keyspace
);
4017 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
4018 sccipher
->setsckey(keyspace
);
4019 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
4020 cscipher
->setcsiv(keyspace
);
4021 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
4022 sccipher
->setsciv(keyspace
);
4023 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
4024 csmac
->setcskey(keyspace
);
4025 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
4026 scmac
->setsckey(keyspace
);
4029 * If this is the first key exchange phase, we must pass the
4030 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4031 * wants to see it but because it will need time to initialise
4032 * itself before it sees an actual packet. In subsequent key
4033 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4034 * it would only confuse the layer above.
4042 * Now we're encrypting. Begin returning 1 to the protocol main
4043 * function so that other things can run on top of the
4044 * transport. If we ever see a KEXINIT, we must go back to the
4047 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
4050 logevent("Server initiated key re-exchange");
4051 goto begin_key_exchange
;
4057 * Add data to an SSH2 channel output buffer.
4059 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4062 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4066 * Attempt to send data on an SSH2 channel.
4068 static int ssh2_try_send(struct ssh_channel
*c
)
4070 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4073 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4074 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4075 len
= c
->v
.v2
.remwindow
;
4076 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4077 len
= c
->v
.v2
.remmaxpkt
;
4078 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
4079 ssh2_pkt_adduint32(c
->remoteid
);
4080 ssh2_pkt_addstring_start();
4081 ssh2_pkt_addstring_data(data
, len
);
4083 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4084 c
->v
.v2
.remwindow
-= len
;
4088 * After having sent as much data as we can, return the amount
4091 return bufchain_size(&c
->v
.v2
.outbuffer
);
4095 * Potentially enlarge the window on an SSH2 channel.
4097 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4100 * Never send WINDOW_ADJUST for a channel that the remote side
4101 * already thinks it's closed; there's no point, since it won't
4102 * be sending any more data anyway.
4107 if (newwin
> c
->v
.v2
.locwindow
) {
4108 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4109 ssh2_pkt_adduint32(c
->remoteid
);
4110 ssh2_pkt_adduint32(newwin
- c
->v
.v2
.locwindow
);
4112 c
->v
.v2
.locwindow
= newwin
;
4117 * Handle the SSH2 userauth and connection layers.
4119 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
4122 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4124 AUTH_KEYBOARD_INTERACTIVE
4128 AUTH_TYPE_PUBLICKEY
,
4129 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4130 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4132 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4133 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4135 static int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4136 static int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4137 static int kbd_inter_running
;
4138 static int we_are_in
;
4139 static int num_prompts
, curr_prompt
, echo
;
4140 static char username
[100];
4141 static int got_username
;
4142 static char pwprompt
[200];
4143 static char password
[100];
4144 static void *publickey_blob
;
4145 static int publickey_bloblen
;
4150 * Request userauth protocol, and await a response to it.
4152 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
4153 ssh2_pkt_addstring("ssh-userauth");
4155 crWaitUntilV(ispkt
);
4156 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4157 bombout(("Server refused user authentication protocol"));
4162 * We repeat this whole loop, including the username prompt,
4163 * until we manage a successful authentication. If the user
4164 * types the wrong _password_, they are sent back to the
4165 * beginning to try another username. (If they specify a
4166 * username in the config, they are never asked, even if they
4167 * do give a wrong password.)
4169 * I think this best serves the needs of
4171 * - the people who have no configuration, no keys, and just
4172 * want to try repeated (username,password) pairs until they
4173 * type both correctly
4175 * - people who have keys and configuration but occasionally
4176 * need to fall back to passwords
4178 * - people with a key held in Pageant, who might not have
4179 * logged in to a particular machine before; so they want to
4180 * type a username, and then _either_ their key will be
4181 * accepted, _or_ they will type a password. If they mistype
4182 * the username they will want to be able to get back and
4186 got_username
= FALSE
;
4191 if (got_username
&& !cfg
.change_username
) {
4193 * We got a username last time round this loop, and
4194 * with change_username turned off we don't try to get
4197 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4198 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4199 if (!ssh_get_line("login as: ",
4200 username
, sizeof(username
), FALSE
)) {
4202 * get_line failed to get a username.
4205 logevent("No username provided. Abandoning session.");
4206 ssh_state
= SSH_STATE_CLOSED
;
4211 c_write_str("login as: ");
4213 setup_userpass_input(username
, sizeof(username
), 1);
4215 crWaitUntilV(!ispkt
);
4216 ret
= process_userpass_input(in
, inlen
);
4221 c_write_str("\r\n");
4222 username
[strcspn(username
, "\n\r")] = '\0';
4225 strncpy(username
, cfg
.username
, sizeof(username
));
4226 username
[sizeof(username
)-1] = '\0';
4227 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4228 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
4232 got_username
= TRUE
;
4235 * Send an authentication request using method "none": (a)
4236 * just in case it succeeds, and (b) so that we know what
4237 * authentication methods we can usefully try next.
4239 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4241 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4242 ssh2_pkt_addstring(username
);
4243 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4244 ssh2_pkt_addstring("none"); /* method */
4246 type
= AUTH_TYPE_NONE
;
4250 tried_pubkey_config
= FALSE
;
4251 tried_agent
= FALSE
;
4252 tried_keyb_inter
= FALSE
;
4253 kbd_inter_running
= FALSE
;
4254 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4257 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4258 keytype
= key_type(cfg
.keyfile
);
4259 if (keytype
== SSH_KEYTYPE_SSH2
)
4260 publickey_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4261 &publickey_bloblen
);
4264 logeventf("Unable to use this key file (%s)",
4265 key_type_to_str(keytype
));
4266 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4267 cfg
.keyfile
, key_type_to_str(keytype
));
4268 c_write_str(msgbuf
);
4269 publickey_blob
= NULL
;
4272 publickey_blob
= NULL
;
4276 * Wait for the result of the last authentication request.
4279 crWaitUntilV(ispkt
);
4280 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4284 * Don't show the banner if we're operating in
4285 * non-verbose non-interactive mode. (It's probably
4286 * a script, which means nobody will read the
4287 * banner _anyway_, and moreover the printing of
4288 * the banner will screw up processing on the
4289 * output of (say) plink.)
4291 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4292 ssh2_pkt_getstring(&banner
, &size
);
4294 c_write_untrusted(banner
, size
);
4296 crWaitUntilV(ispkt
);
4298 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4299 logevent("Access granted");
4304 if (kbd_inter_running
&&
4305 pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4307 * This is either a further set-of-prompts packet
4308 * in keyboard-interactive authentication, or it's
4309 * the same one and we came back here with `gotit'
4310 * set. In the former case, we must reset the
4311 * curr_prompt variable.
4315 } else if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4316 bombout(("Strange packet received during authentication: type %d",
4324 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4325 * we can look at the string in it and know what we can
4326 * helpfully try next.
4328 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4331 ssh2_pkt_getstring(&methods
, &methlen
);
4332 kbd_inter_running
= FALSE
;
4333 if (!ssh2_pkt_getbool()) {
4335 * We have received an unequivocal Access
4336 * Denied. This can translate to a variety of
4339 * - if we'd just tried "none" authentication,
4340 * it's not worth printing anything at all
4342 * - if we'd just tried a public key _offer_,
4343 * the message should be "Server refused our
4344 * key" (or no message at all if the key
4345 * came from Pageant)
4347 * - if we'd just tried anything else, the
4348 * message really should be "Access denied".
4350 * Additionally, if we'd just tried password
4351 * authentication, we should break out of this
4352 * whole loop so as to go back to the username
4355 if (type
== AUTH_TYPE_NONE
) {
4357 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4358 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4359 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4360 c_write_str("Server refused our key\r\n");
4361 logevent("Server refused public key");
4362 } else if (type
== AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4363 /* server declined keyboard-interactive; ignore */
4365 c_write_str("Access denied\r\n");
4366 logevent("Access denied");
4367 if (type
== AUTH_TYPE_PASSWORD
) {
4373 c_write_str("Further authentication required\r\n");
4374 logevent("Further authentication required");
4378 in_commasep_string("publickey", methods
, methlen
);
4380 in_commasep_string("password", methods
, methlen
);
4381 can_keyb_inter
= cfg
.try_ki_auth
&&
4382 in_commasep_string("keyboard-interactive", methods
, methlen
);
4386 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4389 * Most password/passphrase prompts will be
4390 * non-echoing, so we set this to 0 by default.
4391 * Exception is that some keyboard-interactive prompts
4392 * can be echoing, in which case we'll set this to 1.
4396 if (!method
&& can_pubkey
&& agent_exists() && !tried_agent
) {
4398 * Attempt public-key authentication using Pageant.
4400 static unsigned char request
[5], *response
, *p
;
4401 static int responselen
;
4402 static int i
, nkeys
;
4403 static int authed
= FALSE
;
4406 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4407 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4411 logevent("Pageant is running. Requesting keys.");
4413 /* Request the keys held by the agent. */
4414 PUT_32BIT(request
, 1);
4415 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4416 agent_query(request
, 5, &r
, &responselen
);
4417 response
= (unsigned char *) r
;
4418 if (response
&& responselen
>= 5 &&
4419 response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4421 nkeys
= GET_32BIT(p
);
4425 sprintf(buf
, "Pageant has %d SSH2 keys", nkeys
);
4428 for (i
= 0; i
< nkeys
; i
++) {
4429 static char *pkblob
, *alg
, *commentp
;
4430 static int pklen
, alglen
, commentlen
;
4431 static int siglen
, retlen
, len
;
4432 static char *q
, *agentreq
, *ret
;
4437 sprintf(buf
, "Trying Pageant key #%d", i
);
4440 pklen
= GET_32BIT(p
);
4442 if (publickey_blob
&&
4443 pklen
== publickey_bloblen
&&
4444 !memcmp(p
, publickey_blob
, publickey_bloblen
)) {
4445 logevent("This key matches configured key file");
4446 tried_pubkey_config
= 1;
4450 alglen
= GET_32BIT(pkblob
);
4452 commentlen
= GET_32BIT(p
);
4456 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4457 ssh2_pkt_addstring(username
);
4458 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4459 ssh2_pkt_addstring("publickey"); /* method */
4460 ssh2_pkt_addbool(FALSE
); /* no signature included */
4461 ssh2_pkt_addstring_start();
4462 ssh2_pkt_addstring_data(alg
, alglen
);
4463 ssh2_pkt_addstring_start();
4464 ssh2_pkt_addstring_data(pkblob
, pklen
);
4467 crWaitUntilV(ispkt
);
4468 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4469 logevent("Key refused");
4473 if (flags
& FLAG_VERBOSE
) {
4475 ("Authenticating with public key \"");
4476 c_write(commentp
, commentlen
);
4477 c_write_str("\" from agent\r\n");
4481 * Server is willing to accept the key.
4482 * Construct a SIGN_REQUEST.
4484 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4485 ssh2_pkt_addstring(username
);
4486 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4487 ssh2_pkt_addstring("publickey"); /* method */
4488 ssh2_pkt_addbool(TRUE
);
4489 ssh2_pkt_addstring_start();
4490 ssh2_pkt_addstring_data(alg
, alglen
);
4491 ssh2_pkt_addstring_start();
4492 ssh2_pkt_addstring_data(pkblob
, pklen
);
4494 siglen
= pktout
.length
- 5 + 4 + 20;
4495 len
= 1; /* message type */
4496 len
+= 4 + pklen
; /* key blob */
4497 len
+= 4 + siglen
; /* data to sign */
4498 len
+= 4; /* flags */
4499 agentreq
= smalloc(4 + len
);
4500 PUT_32BIT(agentreq
, len
);
4502 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4503 PUT_32BIT(q
, pklen
);
4505 memcpy(q
, pkblob
, pklen
);
4507 PUT_32BIT(q
, siglen
);
4509 /* Now the data to be signed... */
4512 memcpy(q
, ssh2_session_id
, 20);
4514 memcpy(q
, pktout
.data
+ 5, pktout
.length
- 5);
4515 q
+= pktout
.length
- 5;
4516 /* And finally the (zero) flags word. */
4518 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
4522 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4523 logevent("Sending Pageant's response");
4524 ssh2_add_sigblob(pkblob
, pklen
,
4525 ret
+ 9, GET_32BIT(ret
+ 5));
4531 ("Pageant failed to answer challenge");
4541 if (!method
&& can_pubkey
&& publickey_blob
4542 && !tried_pubkey_config
) {
4543 unsigned char *pub_blob
;
4544 char *algorithm
, *comment
;
4547 tried_pubkey_config
= TRUE
;
4549 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4550 ssh_pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4553 * Try the public key supplied in the configuration.
4555 * First, offer the public blob to see if the server is
4556 * willing to accept it.
4558 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4561 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4562 ssh2_pkt_addstring(username
);
4563 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4564 ssh2_pkt_addstring("publickey"); /* method */
4565 ssh2_pkt_addbool(FALSE
); /* no signature included */
4566 ssh2_pkt_addstring(algorithm
);
4567 ssh2_pkt_addstring_start();
4568 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
4570 logevent("Offered public key"); /* FIXME */
4572 crWaitUntilV(ispkt
);
4573 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4575 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4576 continue; /* key refused; give up on it */
4579 logevent("Offer of public key accepted");
4581 * Actually attempt a serious authentication using
4584 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4586 "Passphrase for key \"%.100s\": ",
4592 c_write_str("Authenticating with public key \"");
4593 c_write_str(comment
);
4594 c_write_str("\"\r\n");
4595 method
= AUTH_PUBLICKEY_FILE
;
4599 if (!method
&& can_keyb_inter
&& !tried_keyb_inter
) {
4600 method
= AUTH_KEYBOARD_INTERACTIVE
;
4601 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4602 tried_keyb_inter
= TRUE
;
4604 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4605 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4607 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4608 ssh2_pkt_addstring(username
);
4609 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4610 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4611 ssh2_pkt_addstring(""); /* lang */
4612 ssh2_pkt_addstring("");
4615 crWaitUntilV(ispkt
);
4616 if (pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4617 if (pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4619 logevent("Keyboard-interactive authentication refused");
4620 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4624 kbd_inter_running
= TRUE
;
4628 if (kbd_inter_running
) {
4629 method
= AUTH_KEYBOARD_INTERACTIVE
;
4630 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4631 tried_keyb_inter
= TRUE
;
4633 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4634 ssh_pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4636 if (curr_prompt
== 0) {
4638 * We've got a fresh USERAUTH_INFO_REQUEST.
4639 * Display header data, and start going through
4642 char *name
, *inst
, *lang
;
4643 int name_len
, inst_len
, lang_len
;
4645 ssh2_pkt_getstring(&name
, &name_len
);
4646 ssh2_pkt_getstring(&inst
, &inst_len
);
4647 ssh2_pkt_getstring(&lang
, &lang_len
);
4649 c_write_untrusted(name
, name_len
);
4650 c_write_str("\r\n");
4653 c_write_untrusted(inst
, inst_len
);
4654 c_write_str("\r\n");
4656 num_prompts
= ssh2_pkt_getuint32();
4660 * If there are prompts remaining in the packet,
4661 * display one and get a response.
4663 if (curr_prompt
< num_prompts
) {
4667 ssh2_pkt_getstring(&prompt
, &prompt_len
);
4668 if (prompt_len
> 0) {
4669 strncpy(pwprompt
, prompt
, sizeof(pwprompt
));
4670 pwprompt
[prompt_len
< sizeof(pwprompt
) ?
4671 prompt_len
: sizeof(pwprompt
)-1] = '\0';
4674 "<server failed to send prompt>: ");
4676 echo
= ssh2_pkt_getbool();
4682 if (!method
&& can_passwd
) {
4683 method
= AUTH_PASSWORD
;
4684 ssh_pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4685 ssh_pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4686 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
,
4693 if (!ssh_get_line(pwprompt
, password
,
4694 sizeof(password
), TRUE
)) {
4696 * get_line failed to get a password (for
4697 * example because one was supplied on the
4698 * command line which has already failed to
4701 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4702 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4704 ("No more passwords available to try");
4705 ssh2_pkt_addstring("en"); /* language tag */
4707 logevent("Unable to authenticate");
4708 connection_fatal("Unable to authenticate");
4709 ssh_state
= SSH_STATE_CLOSED
;
4714 c_write_untrusted(pwprompt
, strlen(pwprompt
));
4717 setup_userpass_input(password
, sizeof(password
), echo
);
4719 crWaitUntilV(!ispkt
);
4720 ret
= process_userpass_input(in
, inlen
);
4724 c_write_str("\r\n");
4728 if (method
== AUTH_PUBLICKEY_FILE
) {
4730 * We have our passphrase. Now try the actual authentication.
4732 struct ssh2_userkey
*key
;
4734 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
4735 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4736 if (key
== SSH2_WRONG_PASSPHRASE
) {
4737 c_write_str("Wrong passphrase\r\n");
4738 tried_pubkey_config
= FALSE
;
4740 c_write_str("Unable to load private key\r\n");
4741 tried_pubkey_config
= TRUE
;
4743 /* Send a spurious AUTH_NONE to return to the top. */
4744 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4745 ssh2_pkt_addstring(username
);
4746 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4747 ssh2_pkt_addstring("none"); /* method */
4749 type
= AUTH_TYPE_NONE
;
4751 unsigned char *pkblob
, *sigblob
, *sigdata
;
4752 int pkblob_len
, sigblob_len
, sigdata_len
;
4755 * We have loaded the private key and the server
4756 * has announced that it's willing to accept it.
4757 * Hallelujah. Generate a signature and send it.
4759 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4760 ssh2_pkt_addstring(username
);
4761 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4762 ssh2_pkt_addstring("publickey"); /* method */
4763 ssh2_pkt_addbool(TRUE
);
4764 ssh2_pkt_addstring(key
->alg
->name
);
4765 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4766 ssh2_pkt_addstring_start();
4767 ssh2_pkt_addstring_data(pkblob
, pkblob_len
);
4770 * The data to be signed is:
4774 * followed by everything so far placed in the
4777 sigdata_len
= pktout
.length
- 5 + 4 + 20;
4778 sigdata
= smalloc(sigdata_len
);
4779 PUT_32BIT(sigdata
, 20);
4780 memcpy(sigdata
+ 4, ssh2_session_id
, 20);
4781 memcpy(sigdata
+ 24, pktout
.data
+ 5,
4783 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4784 sigdata_len
, &sigblob_len
);
4785 ssh2_add_sigblob(pkblob
, pkblob_len
,
4786 sigblob
, sigblob_len
);
4792 type
= AUTH_TYPE_PUBLICKEY
;
4794 } else if (method
== AUTH_PASSWORD
) {
4796 * We send the password packet lumped tightly together with
4797 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4798 * string long enough to make the total length of the two
4799 * packets constant. This should ensure that a passive
4800 * listener doing traffic analyis can't work out the length
4803 * For this to work, we need an assumption about the
4804 * maximum length of the password packet. I think 256 is
4805 * pretty conservative. Anyone using a password longer than
4806 * that probably doesn't have much to worry about from
4807 * people who find out how long their password is!
4809 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
4810 ssh2_pkt_addstring(username
);
4811 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4812 ssh2_pkt_addstring("password");
4813 ssh2_pkt_addbool(FALSE
);
4814 ssh2_pkt_addstring(password
);
4817 * We'll include a string that's an exact multiple of the
4818 * cipher block size. If the cipher is NULL for some
4819 * reason, we don't do this trick at all because we gain
4825 stringlen
= (256 - deferred_len
);
4826 stringlen
+= cscipher
->blksize
- 1;
4827 stringlen
-= (stringlen
% cscipher
->blksize
);
4830 * Temporarily disable actual compression,
4831 * so we can guarantee to get this string
4832 * exactly the length we want it. The
4833 * compression-disabling routine should
4834 * return an integer indicating how many
4835 * bytes we should adjust our string length
4838 stringlen
-= cscomp
->disable_compression();
4840 ssh2_pkt_init(SSH2_MSG_IGNORE
);
4841 ssh2_pkt_addstring_start();
4842 for (i
= 0; i
< stringlen
; i
++) {
4843 char c
= (char) random_byte();
4844 ssh2_pkt_addstring_data(&c
, 1);
4848 ssh_pkt_defersend();
4849 logevent("Sent password");
4850 type
= AUTH_TYPE_PASSWORD
;
4851 } else if (method
== AUTH_KEYBOARD_INTERACTIVE
) {
4852 if (curr_prompt
== 0) {
4853 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4854 ssh2_pkt_adduint32(num_prompts
);
4856 if (need_pw
) { /* only add pw if we just got one! */
4857 ssh2_pkt_addstring(password
);
4858 memset(password
, 0, sizeof(password
));
4861 if (curr_prompt
>= num_prompts
) {
4865 * If there are prompts remaining, we set
4866 * `gotit' so that we won't attempt to get
4867 * another packet. Then we go back round the
4868 * loop and will end up retrieving another
4869 * prompt out of the existing packet. Funky or
4874 type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4877 ("No supported authentication methods left to try!\r\n");
4879 ("No supported authentications offered. Disconnecting");
4880 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
4881 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
4883 ("No supported authentication methods available");
4884 ssh2_pkt_addstring("en"); /* language tag */
4886 ssh_state
= SSH_STATE_CLOSED
;
4890 } while (!we_are_in
);
4893 * Now we're authenticated for the connection protocol. The
4894 * connection protocol will automatically have started at this
4895 * point; there's no need to send SERVICE_REQUEST.
4899 * So now create a channel with a session in it.
4901 ssh_channels
= newtree234(ssh_channelcmp
);
4902 mainchan
= smalloc(sizeof(struct ssh_channel
));
4903 mainchan
->localid
= alloc_channel_id();
4904 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
4905 ssh2_pkt_addstring("session");
4906 ssh2_pkt_adduint32(mainchan
->localid
);
4907 mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
4908 ssh2_pkt_adduint32(mainchan
->v
.v2
.locwindow
); /* our window size */
4909 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
4911 crWaitUntilV(ispkt
);
4912 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
4913 bombout(("Server refused to open a session"));
4915 /* FIXME: error data comes back in FAILURE packet */
4917 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
4918 bombout(("Server's channel confirmation cited wrong channel"));
4921 mainchan
->remoteid
= ssh2_pkt_getuint32();
4922 mainchan
->type
= CHAN_MAINSESSION
;
4923 mainchan
->closes
= 0;
4924 mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
4925 mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
4926 bufchain_init(&mainchan
->v
.v2
.outbuffer
);
4927 add234(ssh_channels
, mainchan
);
4928 logevent("Opened channel for session");
4931 * Potentially enable X11 forwarding.
4933 if (cfg
.x11_forward
) {
4934 char proto
[20], data
[64];
4935 logevent("Requesting X11 forwarding");
4936 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
4937 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
4938 ssh2_pkt_adduint32(mainchan
->remoteid
);
4939 ssh2_pkt_addstring("x11-req");
4940 ssh2_pkt_addbool(1); /* want reply */
4941 ssh2_pkt_addbool(0); /* many connections */
4942 ssh2_pkt_addstring(proto
);
4943 ssh2_pkt_addstring(data
);
4944 ssh2_pkt_adduint32(0); /* screen number */
4948 crWaitUntilV(ispkt
);
4949 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
4950 unsigned i
= ssh2_pkt_getuint32();
4951 struct ssh_channel
*c
;
4952 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
4954 continue; /* nonexistent channel */
4955 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
4957 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4959 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
4960 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
4961 bombout(("Unexpected response to X11 forwarding request:"
4962 " packet type %d", pktin
.type
));
4965 logevent("X11 forwarding refused");
4967 logevent("X11 forwarding enabled");
4968 ssh_X11_fwd_enabled
= TRUE
;
4973 * Enable port forwardings.
4976 static char *e
; /* preserve across crReturn */
4979 int sport
,dport
,sserv
,dserv
;
4980 char sports
[256], dports
[256], host
[256];
4984 ssh_rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4985 /* Add port forwardings. */
4990 while (*e
&& *e
!= '\t')
4996 while (*e
&& *e
!= ':')
5006 dport
= atoi(dports
);
5010 se
= getservbyname(dports
, NULL
);
5012 dport
= ntohs(se
->s_port
);
5015 "Service lookup failed for destination port \"%s\"",
5020 sport
= atoi(sports
);
5024 se
= getservbyname(sports
, NULL
);
5026 sport
= ntohs(se
->s_port
);
5029 "Service lookup failed for source port \"%s\"",
5034 if (sport
&& dport
) {
5036 pfd_addforward(host
, dport
, sport
);
5037 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
5038 " %s:%.*s%.*s%d%.*s",
5039 sserv ?
strlen(sports
) : 0, sports
,
5040 sserv
, "(", sport
, sserv
, ")",
5042 dserv ?
strlen(dports
) : 0, dports
,
5043 dserv
, "(", dport
, dserv
, ")");
5046 struct ssh_rportfwd
*pf
;
5047 pf
= smalloc(sizeof(*pf
));
5048 strcpy(pf
->dhost
, host
);
5051 if (add234(ssh_rportfwds
, pf
) != pf
) {
5053 "Duplicate remote port forwarding to %s:%d",
5058 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
5059 " forward to %s:%.*s%.*s%d%.*s",
5060 sserv ?
strlen(sports
) : 0, sports
,
5061 sserv
, "(", sport
, sserv
, ")",
5063 dserv ?
strlen(dports
) : 0, dports
,
5064 dserv
, "(", dport
, dserv
, ")");
5066 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
5067 ssh2_pkt_addstring("tcpip-forward");
5068 ssh2_pkt_addbool(1);/* want reply */
5069 if (cfg
.rport_acceptall
)
5070 ssh2_pkt_addstring("0.0.0.0");
5072 ssh2_pkt_addstring("127.0.0.1");
5073 ssh2_pkt_adduint32(sport
);
5077 crWaitUntilV(ispkt
);
5078 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5079 unsigned i
= ssh2_pkt_getuint32();
5080 struct ssh_channel
*c
;
5081 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5083 continue;/* nonexistent channel */
5084 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5086 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5088 if (pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5089 if (pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5090 bombout(("Unexpected response to port "
5091 "forwarding request: packet type %d",
5095 logevent("Server refused this port forwarding");
5097 logevent("Remote port forwarding enabled");
5106 * Potentially enable agent forwarding.
5108 if (cfg
.agentfwd
&& agent_exists()) {
5109 logevent("Requesting OpenSSH-style agent forwarding");
5110 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5111 ssh2_pkt_adduint32(mainchan
->remoteid
);
5112 ssh2_pkt_addstring("auth-agent-req@openssh.com");
5113 ssh2_pkt_addbool(1); /* want reply */
5117 crWaitUntilV(ispkt
);
5118 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5119 unsigned i
= ssh2_pkt_getuint32();
5120 struct ssh_channel
*c
;
5121 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5123 continue; /* nonexistent channel */
5124 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5126 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5128 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5129 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5130 bombout(("Unexpected response to agent forwarding request:"
5131 " packet type %d", pktin
.type
));
5134 logevent("Agent forwarding refused");
5136 logevent("Agent forwarding enabled");
5137 ssh_agentfwd_enabled
= TRUE
;
5142 * Now allocate a pty for the session.
5145 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5146 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5147 ssh2_pkt_addstring("pty-req");
5148 ssh2_pkt_addbool(1); /* want reply */
5149 ssh2_pkt_addstring(cfg
.termtype
);
5150 ssh2_pkt_adduint32(ssh_term_width
);
5151 ssh2_pkt_adduint32(ssh_term_height
);
5152 ssh2_pkt_adduint32(0); /* pixel width */
5153 ssh2_pkt_adduint32(0); /* pixel height */
5154 ssh2_pkt_addstring_start();
5155 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
5157 ssh_state
= SSH_STATE_INTERMED
;
5160 crWaitUntilV(ispkt
);
5161 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5162 unsigned i
= ssh2_pkt_getuint32();
5163 struct ssh_channel
*c
;
5164 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5166 continue; /* nonexistent channel */
5167 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5169 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5171 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5172 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5173 bombout(("Unexpected response to pty request:"
5174 " packet type %d", pktin
.type
));
5177 c_write_str("Server refused to allocate pty\r\n");
5178 ssh_editing
= ssh_echoing
= 1;
5180 logevent("Allocated pty");
5183 ssh_editing
= ssh_echoing
= 1;
5187 * Start a shell or a remote command. We may have to attempt
5188 * this twice if the config data has provided a second choice
5195 if (ssh_fallback_cmd
) {
5196 subsys
= cfg
.ssh_subsys2
;
5197 cmd
= cfg
.remote_cmd_ptr2
;
5199 subsys
= cfg
.ssh_subsys
;
5200 cmd
= cfg
.remote_cmd_ptr
;
5203 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5204 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
5206 ssh2_pkt_addstring("subsystem");
5207 ssh2_pkt_addbool(1); /* want reply */
5208 ssh2_pkt_addstring(cmd
);
5210 ssh2_pkt_addstring("exec");
5211 ssh2_pkt_addbool(1); /* want reply */
5212 ssh2_pkt_addstring(cmd
);
5214 ssh2_pkt_addstring("shell");
5215 ssh2_pkt_addbool(1); /* want reply */
5219 crWaitUntilV(ispkt
);
5220 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5221 unsigned i
= ssh2_pkt_getuint32();
5222 struct ssh_channel
*c
;
5223 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5225 continue; /* nonexistent channel */
5226 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5228 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5229 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5230 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5231 bombout(("Unexpected response to shell/command request:"
5232 " packet type %d", pktin
.type
));
5236 * We failed to start the command. If this is the
5237 * fallback command, we really are finished; if it's
5238 * not, and if the fallback command exists, try falling
5239 * back to it before complaining.
5241 if (!ssh_fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5242 logevent("Primary command failed; attempting fallback");
5243 ssh_fallback_cmd
= TRUE
;
5246 bombout(("Server refused to start a shell/command"));
5249 logevent("Started a shell/command");
5254 ssh_state
= SSH_STATE_SESSION
;
5256 ssh_size(ssh_term_width
, ssh_term_height
);
5258 ssh_special(TS_EOF
);
5263 ldisc_send(NULL
, 0, 0); /* cause ldisc to notice changes */
5266 static int try_send
;
5270 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5271 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5274 unsigned i
= ssh2_pkt_getuint32();
5275 struct ssh_channel
*c
;
5276 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5278 continue; /* nonexistent channel */
5279 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5280 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
5281 continue; /* extended but not stderr */
5282 ssh2_pkt_getstring(&data
, &length
);
5285 c
->v
.v2
.locwindow
-= length
;
5287 case CHAN_MAINSESSION
:
5289 from_backend(frontend
, pktin
.type
==
5290 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5294 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5297 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5300 while (length
> 0) {
5301 if (c
->u
.a
.lensofar
< 4) {
5302 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5303 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5307 c
->u
.a
.lensofar
+= l
;
5309 if (c
->u
.a
.lensofar
== 4) {
5311 4 + GET_32BIT(c
->u
.a
.msglen
);
5312 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5313 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5315 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5317 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5319 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5323 c
->u
.a
.lensofar
+= l
;
5325 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5326 void *reply
, *sentreply
;
5328 agent_query(c
->u
.a
.message
,
5329 c
->u
.a
.totallen
, &reply
,
5334 /* Fake SSH_AGENT_FAILURE. */
5335 sentreply
= "\0\0\0\1\5";
5338 ssh2_add_channel_data(c
, sentreply
,
5343 sfree(c
->u
.a
.message
);
5344 c
->u
.a
.lensofar
= 0;
5351 * If we are not buffering too much data,
5352 * enlarge the window again at the remote side.
5354 if (bufsize
< OUR_V2_WINSIZE
)
5355 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5357 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
5358 ssh_state
= SSH_STATE_CLOSED
;
5359 logevent("Received disconnect message");
5361 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5362 unsigned i
= ssh2_pkt_getuint32();
5363 struct ssh_channel
*c
;
5365 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5367 continue; /* nonexistent channel */
5369 if (c
->type
== CHAN_X11
) {
5371 * Remote EOF on an X11 channel means we should
5372 * wrap up and close the channel ourselves.
5374 x11_close(c
->u
.x11
.s
);
5376 } else if (c
->type
== CHAN_AGENT
) {
5378 } else if (c
->type
== CHAN_SOCKDATA
) {
5379 pfd_close(c
->u
.pfd
.s
);
5382 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5383 unsigned i
= ssh2_pkt_getuint32();
5384 struct ssh_channel
*c
;
5386 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5387 if (!c
|| ((int)c
->remoteid
) == -1) {
5388 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5389 c ?
"half-open" : "nonexistent", i
));
5391 /* Do pre-close processing on the channel. */
5393 case CHAN_MAINSESSION
:
5394 break; /* nothing to see here, move along */
5396 if (c
->u
.x11
.s
!= NULL
)
5397 x11_close(c
->u
.x11
.s
);
5404 if (c
->u
.pfd
.s
!= NULL
)
5405 pfd_close(c
->u
.pfd
.s
);
5409 if (c
->closes
== 0) {
5410 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5411 ssh2_pkt_adduint32(c
->remoteid
);
5414 del234(ssh_channels
, c
);
5415 bufchain_clear(&c
->v
.v2
.outbuffer
);
5419 * See if that was the last channel left open.
5421 if (count234(ssh_channels
) == 0) {
5424 * We used to send SSH_MSG_DISCONNECT here,
5425 * because I'd believed that _every_ conforming
5426 * SSH2 connection had to end with a disconnect
5427 * being sent by at least one side; apparently
5428 * I was wrong and it's perfectly OK to
5429 * unceremoniously slam the connection shut
5430 * when you're done, and indeed OpenSSH feels
5431 * this is more polite than sending a
5432 * DISCONNECT. So now we don't.
5434 logevent("All channels closed. Disconnecting");
5435 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5436 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5437 ssh2_pkt_addstring("All open channels closed");
5438 ssh2_pkt_addstring("en"); /* language tag */
5441 ssh_state
= SSH_STATE_CLOSED
;
5444 continue; /* remote sends close; ignore (FIXME) */
5445 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5446 unsigned i
= ssh2_pkt_getuint32();
5447 struct ssh_channel
*c
;
5448 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5450 continue; /* nonexistent channel */
5451 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32();
5453 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5454 unsigned i
= ssh2_pkt_getuint32();
5455 struct ssh_channel
*c
;
5456 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5458 continue; /* nonexistent channel */
5459 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5460 continue; /* dunno why they're confirming this */
5461 c
->remoteid
= ssh2_pkt_getuint32();
5462 c
->type
= CHAN_SOCKDATA
;
5463 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32();
5464 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
5466 pfd_confirm(c
->u
.pfd
.s
);
5469 * We have a pending close on this channel,
5470 * which we decided on before the server acked
5471 * the channel open. So now we know the
5472 * remoteid, we can close it again.
5474 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5475 ssh2_pkt_adduint32(c
->remoteid
);
5478 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5479 unsigned i
= ssh2_pkt_getuint32();
5480 struct ssh_channel
*c
;
5481 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
5483 continue; /* nonexistent channel */
5484 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5485 continue; /* dunno why they're failing this */
5487 logevent("Forwarded connection refused by server");
5489 pfd_close(c
->u
.pfd
.s
);
5491 del234(ssh_channels
, c
);
5493 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5496 int typelen
, want_reply
;
5497 struct ssh_channel
*c
;
5499 localid
= ssh2_pkt_getuint32();
5500 ssh2_pkt_getstring(&type
, &typelen
);
5501 want_reply
= ssh2_pkt_getbool();
5504 * First, check that the channel exists. Otherwise,
5505 * we can instantly disconnect with a rude message.
5507 c
= find234(ssh_channels
, &localid
, ssh_channelfind
);
5510 sprintf(buf
, "Received channel request for nonexistent"
5511 " channel %d", localid
);
5513 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5514 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
5515 ssh2_pkt_addstring(buf
);
5516 ssh2_pkt_addstring("en"); /* language tag */
5518 connection_fatal("%s", buf
);
5519 ssh_state
= SSH_STATE_CLOSED
;
5524 * Having got the channel number, we now look at
5525 * the request type string to see if it's something
5528 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5530 /* We recognise "exit-status" on the primary channel. */
5532 ssh_exitcode
= ssh2_pkt_getuint32();
5533 sprintf(buf
, "Server sent command exit status %d",
5537 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS
);
5538 ssh2_pkt_adduint32(c
->remoteid
);
5543 * This is a channel request we don't know
5544 * about, so we now either ignore the request
5545 * or respond with CHANNEL_FAILURE, depending
5549 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE
);
5550 ssh2_pkt_adduint32(c
->remoteid
);
5554 } else if (pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5556 int typelen
, want_reply
;
5558 ssh2_pkt_getstring(&type
, &typelen
);
5559 want_reply
= ssh2_pkt_getbool();
5562 * We currently don't support any global requests
5563 * at all, so we either ignore the request or
5564 * respond with REQUEST_FAILURE, depending on
5568 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5571 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5575 struct ssh_channel
*c
;
5576 unsigned remid
, winsize
, pktsize
;
5577 ssh2_pkt_getstring(&type
, &typelen
);
5578 c
= smalloc(sizeof(struct ssh_channel
));
5580 remid
= ssh2_pkt_getuint32();
5581 winsize
= ssh2_pkt_getuint32();
5582 pktsize
= ssh2_pkt_getuint32();
5584 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5585 if (!ssh_X11_fwd_enabled
)
5586 error
= "X11 forwarding is not enabled";
5587 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5589 error
= "Unable to open an X11 connection";
5593 } else if (typelen
== 15 &&
5594 !memcmp(type
, "forwarded-tcpip", 15)) {
5595 struct ssh_rportfwd pf
, *realpf
;
5598 ssh2_pkt_getstring(&dummy
, &dummylen
);/* skip address */
5599 pf
.sport
= ssh2_pkt_getuint32();
5600 realpf
= find234(ssh_rportfwds
, &pf
, NULL
);
5601 if (realpf
== NULL
) {
5602 error
= "Remote port is not recognised";
5604 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5607 sprintf(buf
, "Received remote port open request for %s:%d",
5608 realpf
->dhost
, realpf
->dport
);
5611 sprintf(buf
, "Port open failed: %s", e
);
5613 error
= "Port open failed";
5615 logevent("Forwarded port opened successfully");
5616 c
->type
= CHAN_SOCKDATA
;
5619 } else if (typelen
== 22 &&
5620 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5621 if (!ssh_agentfwd_enabled
)
5622 error
= "Agent forwarding is not enabled";
5624 c
->type
= CHAN_AGENT
; /* identify channel type */
5625 c
->u
.a
.lensofar
= 0;
5628 error
= "Unsupported channel type requested";
5631 c
->remoteid
= remid
;
5633 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5634 ssh2_pkt_adduint32(c
->remoteid
);
5635 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
5636 ssh2_pkt_addstring(error
);
5637 ssh2_pkt_addstring("en"); /* language tag */
5641 c
->localid
= alloc_channel_id();
5643 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5644 c
->v
.v2
.remwindow
= winsize
;
5645 c
->v
.v2
.remmaxpkt
= pktsize
;
5646 bufchain_init(&c
->v
.v2
.outbuffer
);
5647 add234(ssh_channels
, c
);
5648 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5649 ssh2_pkt_adduint32(c
->remoteid
);
5650 ssh2_pkt_adduint32(c
->localid
);
5651 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);
5652 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5656 bombout(("Strange packet received: type %d", pktin
.type
));
5661 * We have spare data. Add it to the channel buffer.
5663 ssh2_add_channel_data(mainchan
, in
, inlen
);
5668 struct ssh_channel
*c
;
5670 * Try to send data on all channels if we can.
5672 for (i
= 0; NULL
!= (c
= index234(ssh_channels
, i
)); i
++) {
5673 int bufsize
= ssh2_try_send(c
);
5676 case CHAN_MAINSESSION
:
5677 /* stdin need not receive an unthrottle
5678 * notification since it will be polled */
5681 x11_unthrottle(c
->u
.x11
.s
);
5684 /* agent sockets are request/response and need no
5685 * buffer management */
5688 pfd_unthrottle(c
->u
.pfd
.s
);
5700 * Handle the top-level SSH2 protocol.
5702 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
5704 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
5706 do_ssh2_authconn(in
, inlen
, ispkt
);
5710 * Called to set up the connection.
5712 * Returns an error message, or NULL on success.
5714 static char *ssh_init(void *frontend_handle
,
5715 char *host
, int port
, char **realhost
, int nodelay
)
5720 if (crypto_startup() == 0)
5721 return "Microsoft high encryption pack not installed!";
5724 frontend
= frontend_handle
;
5725 ssh_term_width
= cfg
.width
;
5726 ssh_term_height
= cfg
.height
;
5731 ssh1_throttle_count
= 0;
5732 ssh_overall_bufsize
= 0;
5733 ssh_fallback_cmd
= 0;
5735 p
= connect_to_host(host
, port
, realhost
, nodelay
);
5743 * Called to send data down the Telnet connection.
5745 static int ssh_send(char *buf
, int len
)
5747 if (s
== NULL
|| ssh_protocol
== NULL
)
5750 ssh_protocol(buf
, len
, 0);
5752 return ssh_sendbuffer();
5756 * Called to query the current amount of buffered stdin data.
5758 static int ssh_sendbuffer(void)
5762 if (s
== NULL
|| ssh_protocol
== NULL
)
5766 * If the SSH socket itself has backed up, add the total backup
5767 * size on that to any individual buffer on the stdin channel.
5770 if (ssh_throttled_all
)
5771 override_value
= ssh_overall_bufsize
;
5773 if (ssh_version
== 1) {
5774 return override_value
;
5775 } else if (ssh_version
== 2) {
5776 if (!mainchan
|| mainchan
->closes
> 0)
5777 return override_value
;
5779 return override_value
+ bufchain_size(&mainchan
->v
.v2
.outbuffer
);
5786 * Called to set the size of the window from SSH's POV.
5788 static void ssh_size(int width
, int height
)
5790 ssh_term_width
= width
;
5791 ssh_term_height
= height
;
5793 switch (ssh_state
) {
5794 case SSH_STATE_BEFORE_SIZE
:
5795 case SSH_STATE_PREPACKET
:
5796 case SSH_STATE_CLOSED
:
5797 break; /* do nothing */
5798 case SSH_STATE_INTERMED
:
5799 size_needed
= TRUE
; /* buffer for later */
5801 case SSH_STATE_SESSION
:
5805 if (ssh_version
== 1) {
5806 send_packet(SSH1_CMSG_WINDOW_SIZE
,
5807 PKT_INT
, ssh_term_height
, PKT_INT
, ssh_term_width
,
5808 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5810 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
5811 ssh2_pkt_adduint32(mainchan
->remoteid
);
5812 ssh2_pkt_addstring("window-change");
5813 ssh2_pkt_addbool(0);
5814 ssh2_pkt_adduint32(ssh_term_width
);
5815 ssh2_pkt_adduint32(ssh_term_height
);
5816 ssh2_pkt_adduint32(0);
5817 ssh2_pkt_adduint32(0);
5826 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5827 * can send an EOF and collect resulting output (e.g. `plink
5830 static void ssh_special(Telnet_Special code
)
5832 if (code
== TS_EOF
) {
5833 if (ssh_state
!= SSH_STATE_SESSION
) {
5835 * Buffer the EOF in case we are pre-SESSION, so we can
5836 * send it as soon as we reach SESSION.
5842 if (ssh_version
== 1) {
5843 send_packet(SSH1_CMSG_EOF
, PKT_END
);
5845 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
5846 ssh2_pkt_adduint32(mainchan
->remoteid
);
5849 logevent("Sent EOF message");
5850 } else if (code
== TS_PING
) {
5851 if (ssh_state
== SSH_STATE_CLOSED
5852 || ssh_state
== SSH_STATE_PREPACKET
) return;
5853 if (ssh_version
== 1) {
5854 if (!(ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
5855 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
5857 ssh2_pkt_init(SSH2_MSG_IGNORE
);
5858 ssh2_pkt_addstring_start();
5866 void *new_sock_channel(Socket s
)
5868 struct ssh_channel
*c
;
5869 c
= smalloc(sizeof(struct ssh_channel
));
5872 c
->remoteid
= -1; /* to be set when open confirmed */
5873 c
->localid
= alloc_channel_id();
5875 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
5877 bufchain_init(&c
->v
.v2
.outbuffer
);
5878 add234(ssh_channels
, c
);
5884 * This is called when stdout/stderr (the entity to which
5885 * from_backend sends data) manages to clear some backlog.
5887 void ssh_unthrottle(int bufsize
)
5889 if (ssh_version
== 1) {
5890 if (ssh1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
5891 ssh1_stdout_throttling
= 0;
5895 if (mainchan
&& mainchan
->closes
== 0)
5896 ssh2_set_window(mainchan
, OUR_V2_WINSIZE
- bufsize
);
5900 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
5902 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
5905 sprintf(buf
, "Opening forwarded connection to %.512s:%d", hostname
, port
);
5908 if (ssh_version
== 1) {
5909 send_packet(SSH1_MSG_PORT_OPEN
,
5910 PKT_INT
, c
->localid
,
5913 //PKT_STR, <org:orgport>,
5916 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
5917 ssh2_pkt_addstring("direct-tcpip");
5918 ssh2_pkt_adduint32(c
->localid
);
5919 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5920 ssh2_pkt_adduint32(c
->v
.v2
.locwindow
);/* our window size */
5921 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
5922 ssh2_pkt_addstring(hostname
);
5923 ssh2_pkt_adduint32(port
);
5925 * We make up values for the originator data; partly it's
5926 * too much hassle to keep track, and partly I'm not
5927 * convinced the server should be told details like that
5928 * about my local network configuration.
5930 ssh2_pkt_addstring("client-side-connection");
5931 ssh2_pkt_adduint32(0);
5937 static Socket
ssh_socket(void)
5942 static int ssh_sendok(void)
5947 static int ssh_ldisc(int option
)
5949 if (option
== LD_ECHO
)
5951 if (option
== LD_EDIT
)
5956 static int ssh_return_exitcode(void)
5958 return ssh_exitcode
;
5961 Backend ssh_backend
= {
5968 ssh_return_exitcode
,