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 (ssh->s ? sk_close(ssh->s), ssh->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 #define translate(x) if (type == x) return #x
189 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
190 char *ssh1_pkt_type(int type
)
192 translate(SSH1_MSG_DISCONNECT
);
193 translate(SSH1_SMSG_PUBLIC_KEY
);
194 translate(SSH1_CMSG_SESSION_KEY
);
195 translate(SSH1_CMSG_USER
);
196 translate(SSH1_CMSG_AUTH_RSA
);
197 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
198 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
199 translate(SSH1_CMSG_AUTH_PASSWORD
);
200 translate(SSH1_CMSG_REQUEST_PTY
);
201 translate(SSH1_CMSG_WINDOW_SIZE
);
202 translate(SSH1_CMSG_EXEC_SHELL
);
203 translate(SSH1_CMSG_EXEC_CMD
);
204 translate(SSH1_SMSG_SUCCESS
);
205 translate(SSH1_SMSG_FAILURE
);
206 translate(SSH1_CMSG_STDIN_DATA
);
207 translate(SSH1_SMSG_STDOUT_DATA
);
208 translate(SSH1_SMSG_STDERR_DATA
);
209 translate(SSH1_CMSG_EOF
);
210 translate(SSH1_SMSG_EXIT_STATUS
);
211 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
212 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
213 translate(SSH1_MSG_CHANNEL_DATA
);
214 translate(SSH1_MSG_CHANNEL_CLOSE
);
215 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
216 translate(SSH1_SMSG_X11_OPEN
);
217 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
218 translate(SSH1_MSG_PORT_OPEN
);
219 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
220 translate(SSH1_SMSG_AGENT_OPEN
);
221 translate(SSH1_MSG_IGNORE
);
222 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
223 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
224 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
225 translate(SSH1_MSG_DEBUG
);
226 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
227 translate(SSH1_CMSG_AUTH_TIS
);
228 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
229 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
230 translate(SSH1_CMSG_AUTH_CCARD
);
231 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
232 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
235 char *ssh2_pkt_type(int pkt_ctx
, int type
)
237 translate(SSH2_MSG_DISCONNECT
);
238 translate(SSH2_MSG_IGNORE
);
239 translate(SSH2_MSG_UNIMPLEMENTED
);
240 translate(SSH2_MSG_DEBUG
);
241 translate(SSH2_MSG_SERVICE_REQUEST
);
242 translate(SSH2_MSG_SERVICE_ACCEPT
);
243 translate(SSH2_MSG_KEXINIT
);
244 translate(SSH2_MSG_NEWKEYS
);
245 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
246 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
247 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
248 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
249 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
250 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
251 translate(SSH2_MSG_USERAUTH_REQUEST
);
252 translate(SSH2_MSG_USERAUTH_FAILURE
);
253 translate(SSH2_MSG_USERAUTH_SUCCESS
);
254 translate(SSH2_MSG_USERAUTH_BANNER
);
255 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
256 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
257 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
258 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
259 translate(SSH2_MSG_GLOBAL_REQUEST
);
260 translate(SSH2_MSG_REQUEST_SUCCESS
);
261 translate(SSH2_MSG_REQUEST_FAILURE
);
262 translate(SSH2_MSG_CHANNEL_OPEN
);
263 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
264 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
265 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
266 translate(SSH2_MSG_CHANNEL_DATA
);
267 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
268 translate(SSH2_MSG_CHANNEL_EOF
);
269 translate(SSH2_MSG_CHANNEL_CLOSE
);
270 translate(SSH2_MSG_CHANNEL_REQUEST
);
271 translate(SSH2_MSG_CHANNEL_SUCCESS
);
272 translate(SSH2_MSG_CHANNEL_FAILURE
);
278 #define GET_32BIT(cp) \
279 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
280 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
281 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
282 ((unsigned long)(unsigned char)(cp)[3]))
284 #define PUT_32BIT(cp, value) { \
285 (cp)[0] = (unsigned char)((value) >> 24); \
286 (cp)[1] = (unsigned char)((value) >> 16); \
287 (cp)[2] = (unsigned char)((value) >> 8); \
288 (cp)[3] = (unsigned char)(value); }
290 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
292 /* Coroutine mechanics for the sillier bits of the code */
293 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
296 if (!ssh->t) ssh->t = smalloc(sizeof(struct t)); \
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 typedef struct ssh_tag
*Ssh
;
315 extern char *x11_init(Socket
*, char *, void *);
316 extern void x11_close(Socket
);
317 extern int x11_send(Socket
, char *, int);
318 extern void x11_invent_auth(char *, int, char *, int);
319 extern void x11_unthrottle(Socket s
);
320 extern void x11_override_throttle(Socket s
, int enable
);
322 extern char *pfd_newconnect(Socket
* s
, char *hostname
, int port
, void *c
);
323 extern char *pfd_addforward(char *desthost
, int destport
, int port
);
324 extern void pfd_close(Socket s
);
325 extern int pfd_send(Socket s
, char *data
, int len
);
326 extern void pfd_confirm(Socket s
);
327 extern void pfd_unthrottle(Socket s
);
328 extern void pfd_override_throttle(Socket s
, int enable
);
330 static void ssh2_pkt_init(Ssh
, int pkt_type
);
331 static void ssh2_pkt_addbool(Ssh
, unsigned char value
);
332 static void ssh2_pkt_adduint32(Ssh
, unsigned long value
);
333 static void ssh2_pkt_addstring_start(Ssh
);
334 static void ssh2_pkt_addstring_str(Ssh
, char *data
);
335 static void ssh2_pkt_addstring_data(Ssh
, char *data
, int len
);
336 static void ssh2_pkt_addstring(Ssh
, char *data
);
337 static char *ssh2_mpint_fmt(Bignum b
, int *len
);
338 static void ssh2_pkt_addmp(Ssh
, Bignum b
);
339 static int ssh2_pkt_construct(Ssh
);
340 static void ssh2_pkt_send(Ssh
);
343 * Buffer management constants. There are several of these for
344 * various different purposes:
346 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
347 * on a local data stream before we throttle the whole SSH
348 * connection (in SSH1 only). Throttling the whole connection is
349 * pretty drastic so we set this high in the hope it won't
352 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
353 * on the SSH connection itself before we defensively throttle
354 * _all_ local data streams. This is pretty drastic too (though
355 * thankfully unlikely in SSH2 since the window mechanism should
356 * ensure that the server never has any need to throttle its end
357 * of the connection), so we set this high as well.
359 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
363 #define SSH1_BUFFER_LIMIT 32768
364 #define SSH_MAX_BACKLOG 32768
365 #define OUR_V2_WINSIZE 16384
367 const static struct ssh_kex
*kex_algs
[] = {
368 &ssh_diffiehellman_gex
,
372 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
374 static void *nullmac_make_context(void)
378 static void nullmac_free_context(void *handle
)
381 static void nullmac_key(void *handle
, unsigned char *key
)
384 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
388 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
393 const static struct ssh_mac ssh_mac_none
= {
394 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
395 nullmac_generate
, nullmac_verify
, "none", 0
397 const static struct ssh_mac
*macs
[] = {
398 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
400 const static struct ssh_mac
*buggymacs
[] = {
401 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
404 static void *ssh_comp_none_init(void)
408 static void ssh_comp_none_cleanup(void *handle
)
411 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
412 unsigned char **outblock
, int *outlen
)
416 static int ssh_comp_none_disable(void *handle
)
420 const static struct ssh_compress ssh_comp_none
= {
422 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
423 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
424 ssh_comp_none_disable
, NULL
426 extern const struct ssh_compress ssh_zlib
;
427 const static struct ssh_compress
*compressions
[] = {
428 &ssh_zlib
, &ssh_comp_none
431 enum { /* channel types */
436 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
440 * 2-3-4 tree storing channels.
443 Ssh ssh
; /* pointer back to main context */
444 unsigned remoteid
, localid
;
447 * In SSH1, this value contains four bits:
449 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
450 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
451 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
452 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
454 * A channel is completely finished with when all four bits are set.
458 struct ssh1_data_channel
{
461 struct ssh2_data_channel
{
463 unsigned remwindow
, remmaxpkt
;
468 struct ssh_agent_channel
{
469 unsigned char *message
;
470 unsigned char msglen
[4];
471 int lensofar
, totallen
;
473 struct ssh_x11_channel
{
476 struct ssh_pfd_channel
{
483 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
484 * 2 use this structure in different ways, reflecting SSH 2's
485 * altogether saner approach to port forwarding.
487 * In SSH 1, you arrange a remote forwarding by sending the server
488 * the remote port number, and the local destination host:port.
489 * When a connection comes in, the server sends you back that
490 * host:port pair, and you connect to it. This is a ready-made
491 * security hole if you're not on the ball: a malicious server
492 * could send you back _any_ host:port pair, so if you trustingly
493 * connect to the address it gives you then you've just opened the
494 * entire inside of your corporate network just by connecting
495 * through it to a dodgy SSH server. Hence, we must store a list of
496 * host:port pairs we _are_ trying to forward to, and reject a
497 * connection request from the server if it's not in the list.
499 * In SSH 2, each side of the connection minds its own business and
500 * doesn't send unnecessary information to the other. You arrange a
501 * remote forwarding by sending the server just the remote port
502 * number. When a connection comes in, the server tells you which
503 * of its ports was connected to; and _you_ have to remember what
504 * local host:port pair went with that port number.
506 * Hence: in SSH 1 this structure stores host:port pairs we intend
507 * to allow connections to, and is indexed by those host:port
508 * pairs. In SSH 2 it stores a mapping from source port to
509 * destination host:port pair, and is indexed by source port.
511 struct ssh_rportfwd
{
512 unsigned sport
, dport
;
525 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
526 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
527 static void ssh_size(void *handle
, int width
, int height
);
528 static void ssh_special(void *handle
, Telnet_Special
);
529 static int ssh2_try_send(struct ssh_channel
*c
);
530 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
531 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
532 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
533 static int ssh_sendbuffer(void *handle
);
535 struct rdpkt1_state_tag
{
536 long len
, pad
, biglen
, to_read
;
537 unsigned long realcrc
, gotcrc
;
543 struct rdpkt2_state_tag
{
544 long len
, pad
, payload
, packetlen
, maclen
;
547 unsigned long incoming_sequence
;
551 const struct plug_function_table
*fn
;
552 /* the above field _must_ be first in the structure */
554 SHA_State exhash
, exhashbase
;
560 unsigned char session_key
[32];
562 int v1_remote_protoflags
;
563 int v1_local_protoflags
;
564 int agentfwd_enabled
;
567 const struct ssh_cipher
*cipher
;
570 const struct ssh2_cipher
*cscipher
, *sccipher
;
571 void *cs_cipher_ctx
, *sc_cipher_ctx
;
572 const struct ssh_mac
*csmac
, *scmac
;
573 void *cs_mac_ctx
, *sc_mac_ctx
;
574 const struct ssh_compress
*cscomp
, *sccomp
;
575 void *cs_comp_ctx
, *sc_comp_ctx
;
576 const struct ssh_kex
*kex
;
577 const struct ssh_signkey
*hostkey
;
578 unsigned char v2_session_id
[20];
584 int echoing
, editing
;
588 int term_width
, term_height
;
590 tree234
*channels
; /* indexed by local id */
591 struct ssh_channel
*mainchan
; /* primary session channel */
598 SSH_STATE_BEFORE_SIZE
,
604 int size_needed
, eof_needed
;
607 struct Packet pktout
;
608 unsigned char *deferred_send_data
;
609 int deferred_len
, deferred_size
;
612 * Gross hack: pscp will try to start SFTP but fall back to
613 * scp1 if that fails. This variable is the means by which
614 * scp.c can reach into the SSH code and find out which one it
620 * Used for username and password input.
622 char *userpass_input_buffer
;
623 int userpass_input_buflen
;
624 int userpass_input_bufpos
;
625 int userpass_input_echo
;
627 char *portfwd_strptr
;
631 int v1_throttle_count
;
634 int v1_stdout_throttling
;
635 int v2_outgoing_sequence
;
637 int ssh1_rdpkt_crstate
;
638 int ssh2_rdpkt_crstate
;
639 int do_ssh_init_crstate
;
640 int ssh_gotdata_crstate
;
641 int ssh1_protocol_crstate
;
642 int do_ssh1_login_crstate
;
643 int do_ssh2_transport_crstate
;
644 int do_ssh2_authconn_crstate
;
646 void *do_ssh_init_state
;
647 void *do_ssh1_login_state
;
648 void *do_ssh2_transport_state
;
649 void *do_ssh2_authconn_state
;
651 struct rdpkt1_state_tag rdpkt1_state
;
652 struct rdpkt2_state_tag rdpkt2_state
;
654 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
655 int (*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
658 static int ssh_channelcmp(void *av
, void *bv
)
660 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
661 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
662 if (a
->localid
< b
->localid
)
664 if (a
->localid
> b
->localid
)
668 static int ssh_channelfind(void *av
, void *bv
)
670 unsigned *a
= (unsigned *) av
;
671 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
679 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
681 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
682 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
684 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
685 return i
< 0 ?
-1 : +1;
686 if (a
->dport
> b
->dport
)
688 if (a
->dport
< b
->dport
)
693 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
695 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
696 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
698 if (a
->sport
> b
->sport
)
700 if (a
->sport
< b
->sport
)
705 static int alloc_channel_id(Ssh ssh
)
707 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
708 unsigned low
, high
, mid
;
710 struct ssh_channel
*c
;
713 * First-fit allocation of channel numbers: always pick the
714 * lowest unused one. To do this, binary-search using the
715 * counted B-tree to find the largest channel ID which is in a
716 * contiguous sequence from the beginning. (Precisely
717 * everything in that sequence must have ID equal to its tree
718 * index plus CHANNEL_NUMBER_OFFSET.)
720 tsize
= count234(ssh
->channels
);
724 while (high
- low
> 1) {
725 mid
= (high
+ low
) / 2;
726 c
= index234(ssh
->channels
, mid
);
727 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
728 low
= mid
; /* this one is fine */
730 high
= mid
; /* this one is past it */
733 * Now low points to either -1, or the tree index of the
734 * largest ID in the initial sequence.
737 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
738 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
740 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
743 static void c_write(Ssh ssh
, char *buf
, int len
)
745 if ((flags
& FLAG_STDERR
)) {
747 for (i
= 0; i
< len
; i
++)
749 fputc(buf
[i
], stderr
);
752 from_backend(ssh
->frontend
, 1, buf
, len
);
755 static void c_write_untrusted(Ssh ssh
, char *buf
, int len
)
758 for (i
= 0; i
< len
; i
++) {
760 c_write(ssh
, "\r\n", 2);
761 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
762 c_write(ssh
, buf
+ i
, 1);
766 static void c_write_str(Ssh ssh
, char *buf
)
768 c_write(ssh
, buf
, strlen(buf
));
772 * Collect incoming data in the incoming packet buffer.
773 * Decipher and verify the packet when it is completely read.
774 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
775 * Update the *data and *datalen variables.
776 * Return the additional nr of bytes needed, or 0 when
777 * a complete packet is available.
779 static int ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
781 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
783 crBegin(ssh
->ssh1_rdpkt_crstate
);
788 ssh
->pktin
.length
= 0;
790 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
791 while ((*datalen
) == 0)
793 st
->len
= (st
->len
<< 8) + **data
;
794 (*data
)++, (*datalen
)--;
797 st
->pad
= 8 - (st
->len
% 8);
798 st
->biglen
= st
->len
+ st
->pad
;
799 ssh
->pktin
.length
= st
->len
- 5;
801 if (ssh
->pktin
.maxlen
< st
->biglen
) {
802 ssh
->pktin
.maxlen
= st
->biglen
;
803 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
, st
->biglen
+ APIEXTRA
);
806 st
->to_read
= st
->biglen
;
807 st
->p
= ssh
->pktin
.data
;
808 while (st
->to_read
> 0) {
809 st
->chunk
= st
->to_read
;
810 while ((*datalen
) == 0)
811 crReturn(st
->to_read
);
812 if (st
->chunk
> (*datalen
))
813 st
->chunk
= (*datalen
);
814 memcpy(st
->p
, *data
, st
->chunk
);
816 *datalen
-= st
->chunk
;
818 st
->to_read
-= st
->chunk
;
821 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, ssh
->pktin
.data
,
823 bombout(("Network attack (CRC compensation) detected!"));
828 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, ssh
->pktin
.data
, st
->biglen
);
830 st
->realcrc
= crc32(ssh
->pktin
.data
, st
->biglen
- 4);
831 st
->gotcrc
= GET_32BIT(ssh
->pktin
.data
+ st
->biglen
- 4);
832 if (st
->gotcrc
!= st
->realcrc
) {
833 bombout(("Incorrect CRC received on packet"));
837 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
839 if (ssh
->v1_compressing
) {
840 unsigned char *decompblk
;
842 zlib_decompress_block(ssh
->sc_comp_ctx
,
843 ssh
->pktin
.body
- 1, ssh
->pktin
.length
+ 1,
844 &decompblk
, &decomplen
);
846 if (ssh
->pktin
.maxlen
< st
->pad
+ decomplen
) {
847 ssh
->pktin
.maxlen
= st
->pad
+ decomplen
;
848 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
849 ssh
->pktin
.maxlen
+ APIEXTRA
);
850 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
853 memcpy(ssh
->pktin
.body
- 1, decompblk
, decomplen
);
855 ssh
->pktin
.length
= decomplen
- 1;
858 ssh
->pktin
.type
= ssh
->pktin
.body
[-1];
860 log_packet(PKT_INCOMING
, ssh
->pktin
.type
, ssh1_pkt_type(ssh
->pktin
.type
),
861 ssh
->pktin
.body
, ssh
->pktin
.length
);
863 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
864 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
||
865 ssh
->pktin
.type
== SSH1_MSG_DEBUG
||
866 ssh
->pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
867 ssh
->pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
868 long stringlen
= GET_32BIT(ssh
->pktin
.body
);
869 if (stringlen
+ 4 != ssh
->pktin
.length
) {
870 bombout(("Received data packet with bogus string length"));
875 if (ssh
->pktin
.type
== SSH1_MSG_DEBUG
) {
876 /* log debug message */
878 int stringlen
= GET_32BIT(ssh
->pktin
.body
);
879 strcpy(buf
, "Remote debug message: ");
882 memcpy(buf
+ 8, ssh
->pktin
.body
+ 4, stringlen
);
883 buf
[8 + stringlen
] = '\0';
886 } else if (ssh
->pktin
.type
== SSH1_MSG_IGNORE
) {
891 if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
892 /* log reason code in disconnect message */
894 unsigned msglen
= GET_32BIT(ssh
->pktin
.body
);
896 strcpy(buf
, "Remote sent disconnect: ");
897 nowlen
= strlen(buf
);
898 if (msglen
> sizeof(buf
) - nowlen
- 1)
899 msglen
= sizeof(buf
) - nowlen
- 1;
900 memcpy(buf
+ nowlen
, ssh
->pktin
.body
+ 4, msglen
);
901 buf
[nowlen
+ msglen
] = '\0';
902 /* logevent(buf); (this is now done within the bombout macro) */
903 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
910 static int ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
912 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
914 crBegin(ssh
->ssh2_rdpkt_crstate
);
918 ssh
->pktin
.length
= 0;
920 st
->cipherblk
= ssh
->sccipher
->blksize
;
923 if (st
->cipherblk
< 8)
926 if (ssh
->pktin
.maxlen
< st
->cipherblk
) {
927 ssh
->pktin
.maxlen
= st
->cipherblk
;
928 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
, st
->cipherblk
+ APIEXTRA
);
932 * Acquire and decrypt the first block of the packet. This will
933 * contain the length and padding details.
935 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
936 while ((*datalen
) == 0)
937 crReturn(st
->cipherblk
- st
->i
);
938 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
943 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
944 ssh
->pktin
.data
, st
->cipherblk
);
947 * Now get the length and padding figures.
949 st
->len
= GET_32BIT(ssh
->pktin
.data
);
950 st
->pad
= ssh
->pktin
.data
[4];
953 * _Completely_ silly lengths should be stomped on before they
954 * do us any more damage.
956 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
957 bombout(("Incoming packet was garbled on decryption"));
962 * This enables us to deduce the payload length.
964 st
->payload
= st
->len
- st
->pad
- 1;
966 ssh
->pktin
.length
= st
->payload
+ 5;
969 * So now we can work out the total packet length.
971 st
->packetlen
= st
->len
+ 4;
972 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
975 * Adjust memory allocation if packet is too big.
977 if (ssh
->pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
978 ssh
->pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
979 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
980 ssh
->pktin
.maxlen
+ APIEXTRA
);
984 * Read and decrypt the remainder of the packet.
986 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
988 while ((*datalen
) == 0)
989 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
990 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
993 /* Decrypt everything _except_ the MAC. */
995 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
996 ssh
->pktin
.data
+ st
->cipherblk
,
997 st
->packetlen
- st
->cipherblk
);
1003 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, ssh
->pktin
.data
, st
->len
+ 4,
1004 st
->incoming_sequence
)) {
1005 bombout(("Incorrect MAC received on packet"));
1008 st
->incoming_sequence
++; /* whether or not we MACed */
1011 * Decompress packet payload.
1014 unsigned char *newpayload
;
1017 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1018 ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5,
1019 &newpayload
, &newlen
)) {
1020 if (ssh
->pktin
.maxlen
< newlen
+ 5) {
1021 ssh
->pktin
.maxlen
= newlen
+ 5;
1022 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
1023 ssh
->pktin
.maxlen
+ APIEXTRA
);
1025 ssh
->pktin
.length
= 5 + newlen
;
1026 memcpy(ssh
->pktin
.data
+ 5, newpayload
, newlen
);
1031 ssh
->pktin
.savedpos
= 6;
1032 ssh
->pktin
.type
= ssh
->pktin
.data
[5];
1034 log_packet(PKT_INCOMING
, ssh
->pktin
.type
,
1035 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktin
.type
),
1036 ssh
->pktin
.data
+6, ssh
->pktin
.length
-6);
1038 switch (ssh
->pktin
.type
) {
1040 * These packets we must handle instantly.
1042 case SSH2_MSG_DISCONNECT
:
1044 /* log reason code in disconnect message */
1046 int reason
= GET_32BIT(ssh
->pktin
.data
+ 6);
1047 unsigned msglen
= GET_32BIT(ssh
->pktin
.data
+ 10);
1049 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1050 sprintf(buf
, "Received disconnect message (%s)",
1051 ssh2_disconnect_reasons
[reason
]);
1053 sprintf(buf
, "Received disconnect message (unknown type %d)",
1057 strcpy(buf
, "Disconnection message text: ");
1058 nowlen
= strlen(buf
);
1059 if (msglen
> sizeof(buf
) - nowlen
- 1)
1060 msglen
= sizeof(buf
) - nowlen
- 1;
1061 memcpy(buf
+ nowlen
, ssh
->pktin
.data
+ 14, msglen
);
1062 buf
[nowlen
+ msglen
] = '\0';
1064 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1066 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1067 ssh2_disconnect_reasons
[reason
] : "unknown",
1072 case SSH2_MSG_IGNORE
:
1074 case SSH2_MSG_DEBUG
:
1076 /* log the debug message */
1078 /* int display = ssh->pktin.body[6]; */
1079 int stringlen
= GET_32BIT(ssh
->pktin
.data
+7);
1081 strcpy(buf
, "Remote debug message: ");
1082 prefix
= strlen(buf
);
1083 if (stringlen
> (int)(sizeof(buf
)-prefix
-1))
1084 stringlen
= sizeof(buf
)-prefix
-1;
1085 memcpy(buf
+ prefix
, ssh
->pktin
.data
+ 11, stringlen
);
1086 buf
[prefix
+ stringlen
] = '\0';
1089 goto next_packet
; /* FIXME: print the debug message */
1092 * These packets we need do nothing about here.
1094 case SSH2_MSG_UNIMPLEMENTED
:
1095 case SSH2_MSG_SERVICE_REQUEST
:
1096 case SSH2_MSG_SERVICE_ACCEPT
:
1097 case SSH2_MSG_KEXINIT
:
1098 case SSH2_MSG_NEWKEYS
:
1099 case SSH2_MSG_KEXDH_INIT
:
1100 case SSH2_MSG_KEXDH_REPLY
:
1101 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1102 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1103 case SSH2_MSG_KEX_DH_GEX_INIT
:
1104 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1105 case SSH2_MSG_USERAUTH_REQUEST
:
1106 case SSH2_MSG_USERAUTH_FAILURE
:
1107 case SSH2_MSG_USERAUTH_SUCCESS
:
1108 case SSH2_MSG_USERAUTH_BANNER
:
1109 case SSH2_MSG_USERAUTH_PK_OK
:
1110 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1111 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1112 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1113 case SSH2_MSG_GLOBAL_REQUEST
:
1114 case SSH2_MSG_REQUEST_SUCCESS
:
1115 case SSH2_MSG_REQUEST_FAILURE
:
1116 case SSH2_MSG_CHANNEL_OPEN
:
1117 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1118 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1119 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1120 case SSH2_MSG_CHANNEL_DATA
:
1121 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1122 case SSH2_MSG_CHANNEL_EOF
:
1123 case SSH2_MSG_CHANNEL_CLOSE
:
1124 case SSH2_MSG_CHANNEL_REQUEST
:
1125 case SSH2_MSG_CHANNEL_SUCCESS
:
1126 case SSH2_MSG_CHANNEL_FAILURE
:
1130 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1133 ssh2_pkt_init(ssh
, SSH2_MSG_UNIMPLEMENTED
);
1134 ssh2_pkt_adduint32(ssh
, st
->incoming_sequence
- 1);
1142 static void ssh1_pktout_size(Ssh ssh
, int len
)
1146 len
+= 5; /* type and CRC */
1147 pad
= 8 - (len
% 8);
1150 ssh
->pktout
.length
= len
- 5;
1151 if (ssh
->pktout
.maxlen
< biglen
) {
1152 ssh
->pktout
.maxlen
= biglen
;
1154 /* Allocate enough buffer space for extra block
1155 * for MS CryptEncrypt() */
1156 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
, biglen
+ 12);
1158 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
, biglen
+ 4);
1161 ssh
->pktout
.body
= ssh
->pktout
.data
+ 4 + pad
+ 1;
1164 static void s_wrpkt_start(Ssh ssh
, int type
, int len
)
1166 ssh1_pktout_size(ssh
, len
);
1167 ssh
->pktout
.type
= type
;
1170 static int s_wrpkt_prepare(Ssh ssh
)
1172 int pad
, len
, biglen
, i
;
1175 ssh
->pktout
.body
[-1] = ssh
->pktout
.type
;
1177 log_packet(PKT_OUTGOING
, ssh
->pktout
.type
, ssh1_pkt_type(ssh
->pktout
.type
),
1178 ssh
->pktout
.body
, ssh
->pktout
.length
);
1180 if (ssh
->v1_compressing
) {
1181 unsigned char *compblk
;
1183 zlib_compress_block(ssh
->cs_comp_ctx
,
1184 ssh
->pktout
.body
- 1, ssh
->pktout
.length
+ 1,
1185 &compblk
, &complen
);
1186 ssh1_pktout_size(ssh
, complen
- 1);
1187 memcpy(ssh
->pktout
.body
- 1, compblk
, complen
);
1191 len
= ssh
->pktout
.length
+ 5; /* type and CRC */
1192 pad
= 8 - (len
% 8);
1195 for (i
= 0; i
< pad
; i
++)
1196 ssh
->pktout
.data
[i
+ 4] = random_byte();
1197 crc
= crc32(ssh
->pktout
.data
+ 4, biglen
- 4);
1198 PUT_32BIT(ssh
->pktout
.data
+ biglen
, crc
);
1199 PUT_32BIT(ssh
->pktout
.data
, len
);
1202 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, ssh
->pktout
.data
+ 4, biglen
);
1207 static void s_wrpkt(Ssh ssh
)
1210 len
= s_wrpkt_prepare(ssh
);
1211 backlog
= sk_write(ssh
->s
, ssh
->pktout
.data
, len
);
1212 if (backlog
> SSH_MAX_BACKLOG
)
1213 ssh_throttle_all(ssh
, 1, backlog
);
1216 static void s_wrpkt_defer(Ssh ssh
)
1219 len
= s_wrpkt_prepare(ssh
);
1220 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1221 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1222 ssh
->deferred_send_data
= srealloc(ssh
->deferred_send_data
,
1223 ssh
->deferred_size
);
1225 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1226 ssh
->deferred_len
+= len
;
1230 * Construct a packet with the specified contents.
1232 static void construct_packet(Ssh ssh
, int pkttype
, va_list ap1
, va_list ap2
)
1234 unsigned char *p
, *argp
, argchar
;
1235 unsigned long argint
;
1236 int pktlen
, argtype
, arglen
;
1240 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1243 (void) va_arg(ap1
, int);
1247 (void) va_arg(ap1
, char);
1251 (void) va_arg(ap1
, unsigned char *);
1252 arglen
= va_arg(ap1
, int);
1256 argp
= va_arg(ap1
, unsigned char *);
1257 arglen
= strlen(argp
);
1258 pktlen
+= 4 + arglen
;
1261 bn
= va_arg(ap1
, Bignum
);
1262 pktlen
+= ssh1_bignum_length(bn
);
1269 s_wrpkt_start(ssh
, pkttype
, pktlen
);
1270 p
= ssh
->pktout
.body
;
1272 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1275 argint
= va_arg(ap2
, int);
1276 PUT_32BIT(p
, argint
);
1280 argchar
= va_arg(ap2
, unsigned char);
1285 argp
= va_arg(ap2
, unsigned char *);
1286 arglen
= va_arg(ap2
, int);
1287 memcpy(p
, argp
, arglen
);
1291 argp
= va_arg(ap2
, unsigned char *);
1292 arglen
= strlen(argp
);
1293 PUT_32BIT(p
, arglen
);
1294 memcpy(p
+ 4, argp
, arglen
);
1298 bn
= va_arg(ap2
, Bignum
);
1299 p
+= ssh1_write_bignum(p
, bn
);
1305 static void send_packet(Ssh ssh
, int pkttype
, ...)
1308 va_start(ap1
, pkttype
);
1309 va_start(ap2
, pkttype
);
1310 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1314 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1317 va_start(ap1
, pkttype
);
1318 va_start(ap2
, pkttype
);
1319 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1323 static int ssh_versioncmp(char *a
, char *b
)
1326 unsigned long av
, bv
;
1328 av
= strtoul(a
, &ae
, 10);
1329 bv
= strtoul(b
, &be
, 10);
1331 return (av
< bv ?
-1 : +1);
1336 av
= strtoul(ae
, &ae
, 10);
1337 bv
= strtoul(be
, &be
, 10);
1339 return (av
< bv ?
-1 : +1);
1344 * Utility routines for putting an SSH-protocol `string' and
1345 * `uint32' into a SHA state.
1348 static void sha_string(SHA_State
* s
, void *str
, int len
)
1350 unsigned char lenblk
[4];
1351 PUT_32BIT(lenblk
, len
);
1352 SHA_Bytes(s
, lenblk
, 4);
1353 SHA_Bytes(s
, str
, len
);
1356 static void sha_uint32(SHA_State
* s
, unsigned i
)
1358 unsigned char intblk
[4];
1359 PUT_32BIT(intblk
, i
);
1360 SHA_Bytes(s
, intblk
, 4);
1364 * SSH2 packet construction functions.
1366 static void ssh2_pkt_ensure(Ssh ssh
, int length
)
1368 if (ssh
->pktout
.maxlen
< length
) {
1369 ssh
->pktout
.maxlen
= length
+ 256;
1370 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
,
1371 ssh
->pktout
.maxlen
+ APIEXTRA
);
1372 if (!ssh
->pktout
.data
)
1373 fatalbox("Out of memory");
1376 static void ssh2_pkt_adddata(Ssh ssh
, void *data
, int len
)
1378 ssh
->pktout
.length
+= len
;
1379 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
);
1380 memcpy(ssh
->pktout
.data
+ ssh
->pktout
.length
- len
, data
, len
);
1382 static void ssh2_pkt_addbyte(Ssh ssh
, unsigned char byte
)
1384 ssh2_pkt_adddata(ssh
, &byte
, 1);
1386 static void ssh2_pkt_init(Ssh ssh
, int pkt_type
)
1388 ssh
->pktout
.length
= 5;
1389 ssh2_pkt_addbyte(ssh
, (unsigned char) pkt_type
);
1391 static void ssh2_pkt_addbool(Ssh ssh
, unsigned char value
)
1393 ssh2_pkt_adddata(ssh
, &value
, 1);
1395 static void ssh2_pkt_adduint32(Ssh ssh
, unsigned long value
)
1398 PUT_32BIT(x
, value
);
1399 ssh2_pkt_adddata(ssh
, x
, 4);
1401 static void ssh2_pkt_addstring_start(Ssh ssh
)
1403 ssh2_pkt_adduint32(ssh
, 0);
1404 ssh
->pktout
.savedpos
= ssh
->pktout
.length
;
1406 static void ssh2_pkt_addstring_str(Ssh ssh
, char *data
)
1408 ssh2_pkt_adddata(ssh
, data
, strlen(data
));
1409 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1410 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1412 static void ssh2_pkt_addstring_data(Ssh ssh
, char *data
, int len
)
1414 ssh2_pkt_adddata(ssh
, data
, len
);
1415 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1416 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1418 static void ssh2_pkt_addstring(Ssh ssh
, char *data
)
1420 ssh2_pkt_addstring_start(ssh
);
1421 ssh2_pkt_addstring_str(ssh
, data
);
1423 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1426 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1429 fatalbox("out of memory");
1431 for (i
= 1; i
<= n
; i
++)
1432 p
[i
] = bignum_byte(b
, n
- i
);
1434 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1436 memmove(p
, p
+ i
, n
+ 1 - i
);
1440 static void ssh2_pkt_addmp(Ssh ssh
, Bignum b
)
1444 p
= ssh2_mpint_fmt(b
, &len
);
1445 ssh2_pkt_addstring_start(ssh
);
1446 ssh2_pkt_addstring_data(ssh
, p
, len
);
1451 * Construct an SSH2 final-form packet: compress it, encrypt it,
1452 * put the MAC on it. Final packet, ready to be sent, is stored in
1453 * ssh->pktout.data. Total length is returned.
1455 static int ssh2_pkt_construct(Ssh ssh
)
1457 int cipherblk
, maclen
, padding
, i
;
1459 log_packet(PKT_OUTGOING
, ssh
->pktout
.data
[5],
1460 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktout
.data
[5]),
1461 ssh
->pktout
.data
+ 6, ssh
->pktout
.length
- 6);
1464 * Compress packet payload.
1467 unsigned char *newpayload
;
1470 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, ssh
->pktout
.data
+ 5,
1471 ssh
->pktout
.length
- 5,
1472 &newpayload
, &newlen
)) {
1473 ssh
->pktout
.length
= 5;
1474 ssh2_pkt_adddata(ssh
, newpayload
, newlen
);
1480 * Add padding. At least four bytes, and must also bring total
1481 * length (minus MAC) up to a multiple of the block size.
1483 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1484 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1487 (cipherblk
- (ssh
->pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1488 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1489 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
+ padding
+ maclen
);
1490 ssh
->pktout
.data
[4] = padding
;
1491 for (i
= 0; i
< padding
; i
++)
1492 ssh
->pktout
.data
[ssh
->pktout
.length
+ i
] = random_byte();
1493 PUT_32BIT(ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
- 4);
1495 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, ssh
->pktout
.data
,
1496 ssh
->pktout
.length
+ padding
,
1497 ssh
->v2_outgoing_sequence
);
1498 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1501 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1502 ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
);
1504 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1505 return ssh
->pktout
.length
+ padding
+ maclen
;
1509 * Construct and send an SSH2 packet immediately.
1511 static void ssh2_pkt_send(Ssh ssh
)
1515 len
= ssh2_pkt_construct(ssh
);
1516 backlog
= sk_write(ssh
->s
, ssh
->pktout
.data
, len
);
1517 if (backlog
> SSH_MAX_BACKLOG
)
1518 ssh_throttle_all(ssh
, 1, backlog
);
1522 * Construct an SSH2 packet and add it to a deferred data block.
1523 * Useful for sending multiple packets in a single sk_write() call,
1524 * to prevent a traffic-analysing listener from being able to work
1525 * out the length of any particular packet (such as the password
1528 * Note that because SSH2 sequence-numbers its packets, this can
1529 * NOT be used as an m4-style `defer' allowing packets to be
1530 * constructed in one order and sent in another.
1532 static void ssh2_pkt_defer(Ssh ssh
)
1534 int len
= ssh2_pkt_construct(ssh
);
1535 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1536 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1537 ssh
->deferred_send_data
= srealloc(ssh
->deferred_send_data
,
1538 ssh
->deferred_size
);
1540 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1541 ssh
->deferred_len
+= len
;
1545 * Send the whole deferred data block constructed by
1546 * ssh2_pkt_defer() or SSH1's defer_packet().
1548 static void ssh_pkt_defersend(Ssh ssh
)
1551 backlog
= sk_write(ssh
->s
, ssh
->deferred_send_data
, ssh
->deferred_len
);
1552 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1553 sfree(ssh
->deferred_send_data
);
1554 ssh
->deferred_send_data
= NULL
;
1555 if (backlog
> SSH_MAX_BACKLOG
)
1556 ssh_throttle_all(ssh
, 1, backlog
);
1560 void bndebug(char *string
, Bignum b
)
1564 p
= ssh2_mpint_fmt(b
, &len
);
1565 debug(("%s", string
));
1566 for (i
= 0; i
< len
; i
++)
1567 debug((" %02x", p
[i
]));
1573 static void sha_mpint(SHA_State
* s
, Bignum b
)
1577 p
= ssh2_mpint_fmt(b
, &len
);
1578 sha_string(s
, p
, len
);
1583 * SSH2 packet decode functions.
1585 static unsigned long ssh2_pkt_getuint32(Ssh ssh
)
1587 unsigned long value
;
1588 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1589 return 0; /* arrgh, no way to decline (FIXME?) */
1590 value
= GET_32BIT(ssh
->pktin
.data
+ ssh
->pktin
.savedpos
);
1591 ssh
->pktin
.savedpos
+= 4;
1594 static int ssh2_pkt_getbool(Ssh ssh
)
1596 unsigned long value
;
1597 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 1)
1598 return 0; /* arrgh, no way to decline (FIXME?) */
1599 value
= ssh
->pktin
.data
[ssh
->pktin
.savedpos
] != 0;
1600 ssh
->pktin
.savedpos
++;
1603 static void ssh2_pkt_getstring(Ssh ssh
, char **p
, int *length
)
1607 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1609 *length
= GET_32BIT(ssh
->pktin
.data
+ ssh
->pktin
.savedpos
);
1610 ssh
->pktin
.savedpos
+= 4;
1611 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< *length
)
1613 *p
= ssh
->pktin
.data
+ ssh
->pktin
.savedpos
;
1614 ssh
->pktin
.savedpos
+= *length
;
1616 static Bignum
ssh2_pkt_getmp(Ssh ssh
)
1622 ssh2_pkt_getstring(ssh
, &p
, &length
);
1626 bombout(("internal error: Can't handle negative mpints"));
1629 b
= bignum_from_bytes(p
, length
);
1634 * Helper function to add an SSH2 signature blob to a packet.
1635 * Expects to be shown the public key blob as well as the signature
1636 * blob. Normally works just like ssh2_pkt_addstring, but will
1637 * fiddle with the signature packet if necessary for
1638 * BUG_SSH2_RSA_PADDING.
1640 static void ssh2_add_sigblob(Ssh ssh
, void *pkblob_v
, int pkblob_len
,
1641 void *sigblob_v
, int sigblob_len
)
1643 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1644 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1646 /* dmemdump(pkblob, pkblob_len); */
1647 /* dmemdump(sigblob, sigblob_len); */
1650 * See if this is in fact an ssh-rsa signature and a buggy
1651 * server; otherwise we can just do this the easy way.
1653 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1654 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1655 int pos
, len
, siglen
;
1658 * Find the byte length of the modulus.
1661 pos
= 4+7; /* skip over "ssh-rsa" */
1662 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1663 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1664 pos
+= 4; /* find modulus itself */
1665 while (len
> 0 && pkblob
[pos
] == 0)
1667 /* debug(("modulus length is %d\n", len)); */
1670 * Now find the signature integer.
1672 pos
= 4+7; /* skip over "ssh-rsa" */
1673 siglen
= GET_32BIT(sigblob
+pos
);
1674 /* debug(("signature length is %d\n", siglen)); */
1676 if (len
!= siglen
) {
1677 unsigned char newlen
[4];
1678 ssh2_pkt_addstring_start(ssh
);
1679 ssh2_pkt_addstring_data(ssh
, sigblob
, pos
);
1680 /* dmemdump(sigblob, pos); */
1681 pos
+= 4; /* point to start of actual sig */
1682 PUT_32BIT(newlen
, len
);
1683 ssh2_pkt_addstring_data(ssh
, newlen
, 4);
1684 /* dmemdump(newlen, 4); */
1686 while (len
-- > siglen
) {
1687 ssh2_pkt_addstring_data(ssh
, newlen
, 1);
1688 /* dmemdump(newlen, 1); */
1690 ssh2_pkt_addstring_data(ssh
, sigblob
+pos
, siglen
);
1691 /* dmemdump(sigblob+pos, siglen); */
1695 /* Otherwise fall through and do it the easy way. */
1698 ssh2_pkt_addstring_start(ssh
);
1699 ssh2_pkt_addstring_data(ssh
, sigblob
, sigblob_len
);
1703 * Examine the remote side's version string and compare it against
1704 * a list of known buggy implementations.
1706 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1708 char *imp
; /* pointer to implementation part */
1710 imp
+= strcspn(imp
, "-");
1712 imp
+= strcspn(imp
, "-");
1715 ssh
->remote_bugs
= 0;
1717 if (cfg
.sshbug_ignore1
== BUG_ON
||
1718 (cfg
.sshbug_ignore1
== BUG_AUTO
&&
1719 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1720 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1721 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")))) {
1723 * These versions don't support SSH1_MSG_IGNORE, so we have
1724 * to use a different defence against password length
1727 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1728 logevent("We believe remote version has SSH1 ignore bug");
1731 if (cfg
.sshbug_plainpw1
== BUG_ON
||
1732 (cfg
.sshbug_plainpw1
== BUG_AUTO
&&
1733 (!strcmp(imp
, "Cisco-1.25")))) {
1735 * These versions need a plain password sent; they can't
1736 * handle having a null and a random length of data after
1739 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1740 logevent("We believe remote version needs a plain SSH1 password");
1743 if (cfg
.sshbug_rsa1
== BUG_ON
||
1744 (cfg
.sshbug_rsa1
== BUG_AUTO
&&
1745 (!strcmp(imp
, "Cisco-1.25")))) {
1747 * These versions apparently have no clue whatever about
1748 * RSA authentication and will panic and die if they see
1749 * an AUTH_RSA message.
1751 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
1752 logevent("We believe remote version can't handle RSA authentication");
1755 if (cfg
.sshbug_hmac2
== BUG_ON
||
1756 (cfg
.sshbug_hmac2
== BUG_AUTO
&&
1757 (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1758 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1759 !strncmp(imp
, "2.1 ", 4)))) {
1761 * These versions have the HMAC bug.
1763 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
1764 logevent("We believe remote version has SSH2 HMAC bug");
1767 if (cfg
.sshbug_derivekey2
== BUG_ON
||
1768 (cfg
.sshbug_derivekey2
== BUG_AUTO
&&
1769 (!strncmp(imp
, "2.0.", 4)))) {
1771 * These versions have the key-derivation bug (failing to
1772 * include the literal shared secret in the hashes that
1773 * generate the keys).
1775 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1776 logevent("We believe remote version has SSH2 key-derivation bug");
1779 if (cfg
.sshbug_rsapad2
== BUG_ON
||
1780 (cfg
.sshbug_rsapad2
== BUG_AUTO
&&
1781 ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1782 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')))){
1784 * These versions have the SSH2 RSA padding bug.
1786 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1787 logevent("We believe remote version has SSH2 RSA padding bug");
1790 if (cfg
.sshbug_dhgex2
== BUG_ON
) {
1792 * These versions have the SSH2 DH GEX bug.
1794 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
1795 logevent("We believe remote version has SSH2 DH group exchange bug");
1799 static int do_ssh_init(Ssh ssh
, unsigned char c
)
1801 struct do_ssh_init_state
{
1809 crState(do_ssh_init_state
);
1811 crBegin(ssh
->do_ssh_init_crstate
);
1813 /* Search for the string "SSH-" in the input. */
1816 static const int transS
[] = { 1, 2, 2, 1 };
1817 static const int transH
[] = { 0, 0, 3, 0 };
1818 static const int transminus
[] = { 0, 0, 0, -1 };
1820 s
->i
= transS
[s
->i
];
1822 s
->i
= transH
[s
->i
];
1824 s
->i
= transminus
[s
->i
];
1829 crReturn(1); /* get another character */
1833 s
->vstring
= smalloc(s
->vstrsize
);
1834 strcpy(s
->vstring
, "SSH-");
1838 crReturn(1); /* get another char */
1839 if (s
->vslen
>= s
->vstrsize
- 1) {
1841 s
->vstring
= srealloc(s
->vstring
, s
->vstrsize
);
1843 s
->vstring
[s
->vslen
++] = c
;
1846 s
->version
[s
->i
] = '\0';
1848 } else if (s
->i
< sizeof(s
->version
) - 1)
1849 s
->version
[s
->i
++] = c
;
1850 } else if (c
== '\n')
1854 ssh
->agentfwd_enabled
= FALSE
;
1855 ssh
->rdpkt2_state
.incoming_sequence
= 0;
1857 s
->vstring
[s
->vslen
] = 0;
1858 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
1861 vlog
= smalloc(20 + s
->vslen
);
1862 sprintf(vlog
, "Server version: %s", s
->vstring
);
1866 ssh_detect_bugs(ssh
, s
->vstring
);
1869 * Decide which SSH protocol version to support.
1872 /* Anything strictly below "2.0" means protocol 1 is supported. */
1873 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
1874 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1875 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
1877 if (cfg
.sshprot
== 0 && !s
->proto1
) {
1878 bombout(("SSH protocol version 1 required by user but not provided by server"));
1881 if (cfg
.sshprot
== 3 && !s
->proto2
) {
1882 bombout(("SSH protocol version 2 required by user but not provided by server"));
1886 if (s
->proto2
&& (cfg
.sshprot
>= 2 || !s
->proto1
)) {
1890 char verstring
[80], vlog
[100];
1891 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1892 SHA_Init(&ssh
->exhashbase
);
1894 * Hash our version string and their version string.
1896 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
1897 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
1898 sprintf(vlog
, "We claim version: %s", verstring
);
1900 strcat(verstring
, "\n");
1901 logevent("Using SSH protocol version 2");
1902 sk_write(ssh
->s
, verstring
, strlen(verstring
));
1903 ssh
->protocol
= ssh2_protocol
;
1905 ssh
->s_rdpkt
= ssh2_rdpkt
;
1910 char verstring
[80], vlog
[100];
1911 sprintf(verstring
, "SSH-%s-%s",
1912 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
1914 sprintf(vlog
, "We claim version: %s", verstring
);
1916 strcat(verstring
, "\n");
1918 logevent("Using SSH protocol version 1");
1919 sk_write(ssh
->s
, verstring
, strlen(verstring
));
1920 ssh
->protocol
= ssh1_protocol
;
1922 ssh
->s_rdpkt
= ssh1_rdpkt
;
1924 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
1931 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
1933 crBegin(ssh
->ssh_gotdata_crstate
);
1936 * To begin with, feed the characters one by one to the
1937 * protocol initialisation / selection function do_ssh_init().
1938 * When that returns 0, we're done with the initial greeting
1939 * exchange and can move on to packet discipline.
1942 int ret
; /* need not be kept across crReturn */
1944 crReturnV
; /* more data please */
1945 ret
= do_ssh_init(ssh
, *data
);
1953 * We emerge from that loop when the initial negotiation is
1954 * over and we have selected an s_rdpkt function. Now pass
1955 * everything to s_rdpkt, and then pass the resulting packets
1956 * to the proper protocol handler.
1961 while (datalen
> 0) {
1962 if (ssh
->s_rdpkt(ssh
, &data
, &datalen
) == 0) {
1963 if (ssh
->state
== SSH_STATE_CLOSED
) {
1966 ssh
->protocol(ssh
, NULL
, 0, 1);
1967 if (ssh
->state
== SSH_STATE_CLOSED
) {
1977 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1980 Ssh ssh
= (Ssh
) plug
;
1981 ssh
->state
= SSH_STATE_CLOSED
;
1987 /* A socket error has occurred. */
1988 logevent(error_msg
);
1989 connection_fatal(error_msg
);
1991 /* Otherwise, the remote side closed the connection normally. */
1996 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1998 Ssh ssh
= (Ssh
) plug
;
1999 ssh_gotdata(ssh
, data
, len
);
2000 if (ssh
->state
== SSH_STATE_CLOSED
) {
2010 static void ssh_sent(Plug plug
, int bufsize
)
2012 Ssh ssh
= (Ssh
) plug
;
2014 * If the send backlog on the SSH socket itself clears, we
2015 * should unthrottle the whole world if it was throttled.
2017 if (bufsize
< SSH_MAX_BACKLOG
)
2018 ssh_throttle_all(ssh
, 0, bufsize
);
2022 * Connect to specified host and port.
2023 * Returns an error message, or NULL on success.
2024 * Also places the canonical host name into `realhost'. It must be
2025 * freed by the caller.
2027 static char *connect_to_host(Ssh ssh
, char *host
, int port
,
2028 char **realhost
, int nodelay
)
2030 static const struct plug_function_table fn_table
= {
2040 ssh
->savedhost
= smalloc(1 + strlen(host
));
2041 if (!ssh
->savedhost
)
2042 fatalbox("Out of memory");
2043 strcpy(ssh
->savedhost
, host
);
2046 port
= 22; /* default ssh port */
2047 ssh
->savedport
= port
;
2054 sprintf(buf
, "Looking up host \"%.170s\"", host
);
2057 addr
= sk_namelookup(host
, realhost
);
2058 if ((err
= sk_addr_error(addr
)))
2065 char buf
[200], addrbuf
[100];
2066 sk_getaddr(addr
, addrbuf
, 100);
2067 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
2070 ssh
->fn
= &fn_table
;
2071 ssh
->s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, (Plug
) ssh
);
2072 if ((err
= sk_socket_error(ssh
->s
))) {
2081 * Throttle or unthrottle the SSH connection.
2083 static void ssh1_throttle(Ssh ssh
, int adjust
)
2085 int old_count
= ssh
->v1_throttle_count
;
2086 ssh
->v1_throttle_count
+= adjust
;
2087 assert(ssh
->v1_throttle_count
>= 0);
2088 if (ssh
->v1_throttle_count
&& !old_count
) {
2089 sk_set_frozen(ssh
->s
, 1);
2090 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2091 sk_set_frozen(ssh
->s
, 0);
2096 * Throttle or unthrottle _all_ local data streams (for when sends
2097 * on the SSH connection itself back up).
2099 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2102 struct ssh_channel
*c
;
2104 if (enable
== ssh
->throttled_all
)
2106 ssh
->throttled_all
= enable
;
2107 ssh
->overall_bufsize
= bufsize
;
2110 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2112 case CHAN_MAINSESSION
:
2114 * This is treated separately, outside the switch.
2118 x11_override_throttle(c
->u
.x11
.s
, enable
);
2121 /* Agent channels require no buffer management. */
2124 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2131 * Username and password input, abstracted off into routines
2132 * reusable in several places - even between SSH1 and SSH2.
2135 /* Set up a username or password input loop on a given buffer. */
2136 void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2138 ssh
->userpass_input_buffer
= buffer
;
2139 ssh
->userpass_input_buflen
= buflen
;
2140 ssh
->userpass_input_bufpos
= 0;
2141 ssh
->userpass_input_echo
= echo
;
2145 * Process some terminal data in the course of username/password
2146 * input. Returns >0 for success (line of input returned in
2147 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2148 * for inconclusive (keep waiting for more input please).
2150 int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2155 switch (c
= *in
++) {
2158 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2159 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2164 if (ssh
->userpass_input_bufpos
> 0) {
2165 if (ssh
->userpass_input_echo
)
2166 c_write_str(ssh
, "\b \b");
2167 ssh
->userpass_input_bufpos
--;
2172 while (ssh
->userpass_input_bufpos
> 0) {
2173 if (ssh
->userpass_input_echo
)
2174 c_write_str(ssh
, "\b \b");
2175 ssh
->userpass_input_bufpos
--;
2183 if (((c
>= ' ' && c
<= '~') ||
2184 ((unsigned char) c
>= 160))
2185 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2186 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2187 if (ssh
->userpass_input_echo
)
2188 c_write(ssh
, &c
, 1);
2197 * Handle the key exchange and user authentication phases.
2199 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
2202 unsigned char cookie
[8];
2203 struct RSAKey servkey
, hostkey
;
2204 struct MD5Context md5c
;
2205 struct do_ssh1_login_state
{
2207 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2208 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2209 int tried_publickey
, tried_agent
;
2210 int tis_auth_refused
, ccard_auth_refused
;
2211 unsigned char session_id
[16];
2214 void *publickey_blob
;
2215 int publickey_bloblen
;
2221 unsigned char request
[5], *response
, *p
;
2230 crState(do_ssh1_login_state
);
2232 crBegin(ssh
->do_ssh1_login_crstate
);
2237 if (ssh
->pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2238 bombout(("Public key packet not received"));
2242 logevent("Received public keys");
2244 memcpy(cookie
, ssh
->pktin
.body
, 8);
2246 i
= makekey(ssh
->pktin
.body
+ 8, &servkey
, &s
->keystr1
, 0);
2247 j
= makekey(ssh
->pktin
.body
+ 8 + i
, &hostkey
, &s
->keystr2
, 0);
2250 * Log the host key fingerprint.
2254 logevent("Host key fingerprint is:");
2255 strcpy(logmsg
, " ");
2256 hostkey
.comment
= NULL
;
2257 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2258 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2262 ssh
->v1_remote_protoflags
= GET_32BIT(ssh
->pktin
.body
+ 8 + i
+ j
);
2263 s
->supported_ciphers_mask
= GET_32BIT(ssh
->pktin
.body
+ 12 + i
+ j
);
2264 s
->supported_auths_mask
= GET_32BIT(ssh
->pktin
.body
+ 16 + i
+ j
);
2266 ssh
->v1_local_protoflags
=
2267 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2268 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2271 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2272 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2273 MD5Update(&md5c
, ssh
->pktin
.body
, 8);
2274 MD5Final(s
->session_id
, &md5c
);
2276 for (i
= 0; i
< 32; i
++)
2277 ssh
->session_key
[i
] = random_byte();
2279 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2281 s
->rsabuf
= smalloc(s
->len
);
2283 fatalbox("Out of memory");
2286 * Verify the host key.
2290 * First format the key into a string.
2292 int len
= rsastr_len(&hostkey
);
2293 char fingerprint
[100];
2294 char *keystr
= smalloc(len
);
2296 fatalbox("Out of memory");
2297 rsastr_fmt(keystr
, &hostkey
);
2298 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2299 verify_ssh_host_key(ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2304 for (i
= 0; i
< 32; i
++) {
2305 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2307 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2310 if (hostkey
.bytes
> servkey
.bytes
) {
2311 rsaencrypt(s
->rsabuf
, 32, &servkey
);
2312 rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2314 rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2315 rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2318 logevent("Encrypted session key");
2321 int cipher_chosen
= 0, warn
= 0;
2322 char *cipher_string
= NULL
;
2324 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2325 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2326 if (next_cipher
== CIPHER_WARN
) {
2327 /* If/when we choose a cipher, warn about it */
2329 } else if (next_cipher
== CIPHER_AES
) {
2330 /* XXX Probably don't need to mention this. */
2331 logevent("AES not supported in SSH1, skipping");
2333 switch (next_cipher
) {
2334 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2335 cipher_string
= "3DES"; break;
2336 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2337 cipher_string
= "Blowfish"; break;
2338 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2339 cipher_string
= "single-DES"; break;
2341 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2345 if (!cipher_chosen
) {
2346 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2347 bombout(("Server violates SSH 1 protocol by not "
2348 "supporting 3DES encryption"));
2350 /* shouldn't happen */
2351 bombout(("No supported ciphers found"));
2355 /* Warn about chosen cipher if necessary. */
2357 askcipher(cipher_string
, 0);
2360 switch (s
->cipher_type
) {
2361 case SSH_CIPHER_3DES
:
2362 logevent("Using 3DES encryption");
2364 case SSH_CIPHER_DES
:
2365 logevent("Using single-DES encryption");
2367 case SSH_CIPHER_BLOWFISH
:
2368 logevent("Using Blowfish encryption");
2372 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2373 PKT_CHAR
, s
->cipher_type
,
2374 PKT_DATA
, cookie
, 8,
2375 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2376 PKT_DATA
, s
->rsabuf
, s
->len
,
2377 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2379 logevent("Trying to enable encryption...");
2383 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2384 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2386 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2387 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2390 sprintf(buf
, "Initialised %.200s encryption", ssh
->cipher
->text_name
);
2394 ssh
->crcda_ctx
= crcda_make_context();
2395 logevent("Installing CRC compensation attack detector");
2399 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2400 bombout(("Encryption not successfully enabled"));
2404 logevent("Successfully started encryption");
2408 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2409 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2410 if (!ssh_get_line("login as: ",
2411 s
->username
, sizeof(s
->username
), FALSE
)) {
2413 * get_line failed to get a username.
2416 logevent("No username provided. Abandoning session.");
2417 ssh
->state
= SSH_STATE_CLOSED
;
2421 int ret
; /* need not be kept over crReturn */
2422 c_write_str(ssh
, "login as: ");
2425 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2427 crWaitUntil(!ispkt
);
2428 ret
= process_userpass_input(ssh
, in
, inlen
);
2432 c_write_str(ssh
, "\r\n");
2435 strncpy(s
->username
, cfg
.username
, sizeof(s
->username
));
2436 s
->username
[sizeof(s
->username
)-1] = '\0';
2439 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2441 char userlog
[22 + sizeof(s
->username
)];
2442 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2444 if (flags
& FLAG_INTERACTIVE
&&
2445 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2446 strcat(userlog
, "\r\n");
2447 c_write_str(ssh
, userlog
);
2454 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2455 /* We must not attempt PK auth. Pretend we've already tried it. */
2456 s
->tried_publickey
= s
->tried_agent
= 1;
2458 s
->tried_publickey
= s
->tried_agent
= 0;
2460 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2461 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2463 if (!rsakey_pubblob(cfg
.keyfile
,
2464 &s
->publickey_blob
, &s
->publickey_bloblen
))
2465 s
->publickey_blob
= NULL
;
2467 s
->publickey_blob
= NULL
;
2469 while (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2470 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2472 if (agent_exists() && !s
->tried_agent
) {
2474 * Attempt RSA authentication using Pageant.
2480 logevent("Pageant is running. Requesting keys.");
2482 /* Request the keys held by the agent. */
2483 PUT_32BIT(s
->request
, 1);
2484 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2485 agent_query(s
->request
, 5, &r
, &s
->responselen
);
2486 s
->response
= (unsigned char *) r
;
2487 if (s
->response
&& s
->responselen
>= 5 &&
2488 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2489 s
->p
= s
->response
+ 5;
2490 s
->nkeys
= GET_32BIT(s
->p
);
2494 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2497 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2500 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2503 if (s
->publickey_blob
&&
2504 !memcmp(s
->p
, s
->publickey_blob
,
2505 s
->publickey_bloblen
)) {
2506 logevent("This key matches configured key file");
2507 s
->tried_publickey
= 1;
2510 s
->p
+= ssh1_read_bignum(s
->p
, &s
->key
.exponent
);
2511 s
->p
+= ssh1_read_bignum(s
->p
, &s
->key
.modulus
);
2512 s
->commentlen
= GET_32BIT(s
->p
);
2515 s
->p
+= s
->commentlen
;
2516 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2517 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2519 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2520 logevent("Key refused");
2523 logevent("Received RSA challenge");
2524 ssh1_read_bignum(ssh
->pktin
.body
, &s
->challenge
);
2526 char *agentreq
, *q
, *ret
;
2529 len
= 1 + 4; /* message type, bit count */
2530 len
+= ssh1_bignum_length(s
->key
.exponent
);
2531 len
+= ssh1_bignum_length(s
->key
.modulus
);
2532 len
+= ssh1_bignum_length(s
->challenge
);
2533 len
+= 16; /* session id */
2534 len
+= 4; /* response format */
2535 agentreq
= smalloc(4 + len
);
2536 PUT_32BIT(agentreq
, len
);
2538 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2539 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2541 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2542 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2543 q
+= ssh1_write_bignum(q
, s
->challenge
);
2544 memcpy(q
, s
->session_id
, 16);
2546 PUT_32BIT(q
, 1); /* response format */
2547 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2551 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2552 logevent("Sending Pageant's response");
2553 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2554 PKT_DATA
, ret
+ 5, 16,
2558 if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
2560 ("Pageant's response accepted");
2561 if (flags
& FLAG_VERBOSE
) {
2562 c_write_str(ssh
, "Authenticated using"
2564 c_write(ssh
, s
->commentp
,
2566 c_write_str(ssh
, "\" from agent\r\n");
2571 ("Pageant's response not accepted");
2574 ("Pageant failed to answer challenge");
2578 logevent("No reply received from Pageant");
2581 freebn(s
->key
.exponent
);
2582 freebn(s
->key
.modulus
);
2583 freebn(s
->challenge
);
2591 if (*cfg
.keyfile
&& !s
->tried_publickey
)
2592 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2594 if (cfg
.try_tis_auth
&&
2595 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2596 !s
->tis_auth_refused
) {
2597 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2598 logevent("Requested TIS authentication");
2599 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
2601 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2602 logevent("TIS authentication declined");
2603 if (flags
& FLAG_INTERACTIVE
)
2604 c_write_str(ssh
, "TIS authentication refused.\r\n");
2605 s
->tis_auth_refused
= 1;
2608 int challengelen
= GET_32BIT(ssh
->pktin
.body
);
2609 logevent("Received TIS challenge");
2610 if (challengelen
> sizeof(s
->prompt
) - 1)
2611 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2612 memcpy(s
->prompt
, ssh
->pktin
.body
+ 4, challengelen
);
2613 /* Prompt heuristic comes from OpenSSH */
2614 strncpy(s
->prompt
+ challengelen
,
2615 memchr(s
->prompt
, '\n', challengelen
) ?
2616 "": "\r\nResponse: ",
2617 (sizeof s
->prompt
) - challengelen
);
2618 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
2621 if (cfg
.try_tis_auth
&&
2622 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2623 !s
->ccard_auth_refused
) {
2624 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2625 logevent("Requested CryptoCard authentication");
2626 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2628 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2629 logevent("CryptoCard authentication declined");
2630 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
2631 s
->ccard_auth_refused
= 1;
2634 int challengelen
= GET_32BIT(ssh
->pktin
.body
);
2635 logevent("Received CryptoCard challenge");
2636 if (challengelen
> sizeof(s
->prompt
) - 1)
2637 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2638 memcpy(s
->prompt
, ssh
->pktin
.body
+ 4, challengelen
);
2639 strncpy(s
->prompt
+ challengelen
,
2640 memchr(s
->prompt
, '\n', challengelen
) ?
2641 "" : "\r\nResponse: ",
2642 sizeof(s
->prompt
) - challengelen
);
2643 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
2646 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2647 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
2648 s
->username
, ssh
->savedhost
);
2650 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2651 char *comment
= NULL
;
2654 if (flags
& FLAG_VERBOSE
)
2655 c_write_str(ssh
, "Trying public key authentication.\r\n");
2656 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2658 type
= key_type(cfg
.keyfile
);
2659 if (type
!= SSH_KEYTYPE_SSH1
) {
2660 sprintf(msgbuf
, "Key is of wrong type (%s)",
2661 key_type_to_str(type
));
2663 c_write_str(ssh
, msgbuf
);
2664 c_write_str(ssh
, "\r\n");
2665 s
->tried_publickey
= 1;
2668 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2669 if (flags
& FLAG_VERBOSE
)
2670 c_write_str(ssh
, "No passphrase required.\r\n");
2673 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
2678 * Show password prompt, having first obtained it via a TIS
2679 * or CryptoCard exchange if we're doing TIS or CryptoCard
2683 if (!ssh_get_line(s
->prompt
, s
->password
,
2684 sizeof(s
->password
), TRUE
)) {
2686 * get_line failed to get a password (for example
2687 * because one was supplied on the command line
2688 * which has already failed to work). Terminate.
2690 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
2691 PKT_STR
, "No more passwords available to try",
2693 logevent("Unable to authenticate");
2694 connection_fatal("Unable to authenticate");
2695 ssh
->state
= SSH_STATE_CLOSED
;
2699 /* Prompt may have come from server. We've munged it a bit, so
2700 * we know it to be zero-terminated at least once. */
2701 int ret
; /* need not be saved over crReturn */
2702 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
2705 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
2707 crWaitUntil(!ispkt
);
2708 ret
= process_userpass_input(ssh
, in
, inlen
);
2712 c_write_str(ssh
, "\r\n");
2716 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2718 * Try public key authentication with the specified
2721 s
->tried_publickey
= 1;
2724 int ret
= loadrsakey(cfg
.keyfile
, &s
->key
, s
->password
);
2726 c_write_str(ssh
, "Couldn't load private key from ");
2727 c_write_str(ssh
, cfg
.keyfile
);
2728 c_write_str(ssh
, ".\r\n");
2729 continue; /* go and try password */
2732 c_write_str(ssh
, "Wrong passphrase.\r\n");
2733 s
->tried_publickey
= 0;
2734 continue; /* try again */
2739 * Send a public key attempt.
2741 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2742 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2745 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2746 c_write_str(ssh
, "Server refused our public key.\r\n");
2747 continue; /* go and try password */
2749 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2750 bombout(("Bizarre response to offer of public key"));
2756 unsigned char buffer
[32];
2757 Bignum challenge
, response
;
2759 ssh1_read_bignum(ssh
->pktin
.body
, &challenge
);
2760 response
= rsadecrypt(challenge
, &s
->key
);
2761 freebn(s
->key
.private_exponent
);/* burn the evidence */
2763 for (i
= 0; i
< 32; i
++) {
2764 buffer
[i
] = bignum_byte(response
, 31 - i
);
2768 MD5Update(&md5c
, buffer
, 32);
2769 MD5Update(&md5c
, s
->session_id
, 16);
2770 MD5Final(buffer
, &md5c
);
2772 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2773 PKT_DATA
, buffer
, 16, PKT_END
);
2780 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2781 if (flags
& FLAG_VERBOSE
)
2782 c_write_str(ssh
, "Failed to authenticate with"
2783 " our public key.\r\n");
2784 continue; /* go and try password */
2785 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2786 bombout(("Bizarre response to RSA authentication response"));
2790 break; /* we're through! */
2792 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2794 * Defence against traffic analysis: we send a
2795 * whole bunch of packets containing strings of
2796 * different lengths. One of these strings is the
2797 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2798 * The others are all random data in
2799 * SSH1_MSG_IGNORE packets. This way a passive
2800 * listener can't tell which is the password, and
2801 * hence can't deduce the password length.
2803 * Anybody with a password length greater than 16
2804 * bytes is going to have enough entropy in their
2805 * password that a listener won't find it _that_
2806 * much help to know how long it is. So what we'll
2809 * - if password length < 16, we send 15 packets
2810 * containing string lengths 1 through 15
2812 * - otherwise, we let N be the nearest multiple
2813 * of 8 below the password length, and send 8
2814 * packets containing string lengths N through
2815 * N+7. This won't obscure the order of
2816 * magnitude of the password length, but it will
2817 * introduce a bit of extra uncertainty.
2819 * A few servers (the old 1.2.18 through 1.2.22)
2820 * can't deal with SSH1_MSG_IGNORE. For these
2821 * servers, we need an alternative defence. We make
2822 * use of the fact that the password is interpreted
2823 * as a C string: so we can append a NUL, then some
2826 * One server (a Cisco one) can deal with neither
2827 * SSH1_MSG_IGNORE _nor_ a padded password string.
2828 * For this server we are left with no defences
2829 * against password length sniffing.
2831 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2833 * The server can deal with SSH1_MSG_IGNORE, so
2834 * we can use the primary defence.
2836 int bottom
, top
, pwlen
, i
;
2839 pwlen
= strlen(s
->password
);
2841 bottom
= 0; /* zero length passwords are OK! :-) */
2844 bottom
= pwlen
& ~7;
2848 assert(pwlen
>= bottom
&& pwlen
<= top
);
2850 randomstr
= smalloc(top
+ 1);
2852 for (i
= bottom
; i
<= top
; i
++) {
2854 defer_packet(ssh
, s
->pwpkt_type
,
2855 PKT_STR
, s
->password
, PKT_END
);
2857 for (j
= 0; j
< i
; j
++) {
2859 randomstr
[j
] = random_byte();
2860 } while (randomstr
[j
] == '\0');
2862 randomstr
[i
] = '\0';
2863 defer_packet(ssh
, SSH1_MSG_IGNORE
,
2864 PKT_STR
, randomstr
, PKT_END
);
2867 logevent("Sending password with camouflage packets");
2868 ssh_pkt_defersend(ssh
);
2870 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2872 * The server can't deal with SSH1_MSG_IGNORE
2873 * but can deal with padded passwords, so we
2874 * can use the secondary defence.
2880 len
= strlen(s
->password
);
2881 if (len
< sizeof(string
)) {
2883 strcpy(string
, s
->password
);
2884 len
++; /* cover the zero byte */
2885 while (len
< sizeof(string
)) {
2886 string
[len
++] = (char) random_byte();
2891 logevent("Sending length-padded password");
2892 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
2893 PKT_DATA
, ss
, len
, PKT_END
);
2896 * The server has _both_
2897 * BUG_CHOKES_ON_SSH1_IGNORE and
2898 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2899 * therefore nothing we can do.
2902 len
= strlen(s
->password
);
2903 logevent("Sending unpadded password");
2904 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
2905 PKT_DATA
, s
->password
, len
, PKT_END
);
2908 send_packet(ssh
, s
->pwpkt_type
, PKT_STR
, s
->password
, PKT_END
);
2911 logevent("Sent password");
2912 memset(s
->password
, 0, strlen(s
->password
));
2914 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2915 if (flags
& FLAG_VERBOSE
)
2916 c_write_str(ssh
, "Access denied\r\n");
2917 logevent("Authentication refused");
2918 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2919 bombout(("Strange packet received, type %d", ssh
->pktin
.type
));
2924 logevent("Authentication successful");
2929 void sshfwd_close(struct ssh_channel
*c
)
2933 if (c
&& !c
->closes
) {
2935 * If the channel's remoteid is -1, we have sent
2936 * CHANNEL_OPEN for this channel, but it hasn't even been
2937 * acknowledged by the server. So we must set a close flag
2938 * on it now, and then when the server acks the channel
2939 * open, we can close it then.
2941 if (((int)c
->remoteid
) != -1) {
2942 if (ssh
->version
== 1) {
2943 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2946 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
2947 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
2951 c
->closes
= 1; /* sent MSG_CLOSE */
2952 if (c
->type
== CHAN_X11
) {
2954 logevent("Forwarded X11 connection terminated");
2955 } else if (c
->type
== CHAN_SOCKDATA
||
2956 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2958 logevent("Forwarded port closed");
2963 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2967 if (ssh
->version
== 1) {
2968 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2969 PKT_INT
, c
->remoteid
,
2970 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2972 * In SSH1 we can return 0 here - implying that forwarded
2973 * connections are never individually throttled - because
2974 * the only circumstance that can cause throttling will be
2975 * the whole SSH connection backing up, in which case
2976 * _everything_ will be throttled as a whole.
2980 ssh2_add_channel_data(c
, buf
, len
);
2981 return ssh2_try_send(c
);
2985 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2989 if (ssh
->version
== 1) {
2990 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2991 c
->v
.v1
.throttling
= 0;
2992 ssh1_throttle(ssh
, -1);
2995 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
2999 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3001 crBegin(ssh
->ssh1_protocol_crstate
);
3005 while (!do_ssh1_login(ssh
, in
, inlen
, ispkt
)) {
3008 if (ssh
->state
== SSH_STATE_CLOSED
)
3011 if (cfg
.agentfwd
&& agent_exists()) {
3012 logevent("Requesting agent forwarding");
3013 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3017 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3018 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3019 bombout(("Protocol confusion"));
3021 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3022 logevent("Agent forwarding refused");
3024 logevent("Agent forwarding enabled");
3025 ssh
->agentfwd_enabled
= TRUE
;
3029 if (cfg
.x11_forward
) {
3030 char proto
[20], data
[64];
3031 logevent("Requesting X11 forwarding");
3032 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
3033 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3034 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3035 PKT_STR
, proto
, PKT_STR
, data
,
3036 PKT_INT
, 0, PKT_END
);
3038 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3039 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3044 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3045 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3046 bombout(("Protocol confusion"));
3048 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3049 logevent("X11 forwarding refused");
3051 logevent("X11 forwarding enabled");
3052 ssh
->X11_fwd_enabled
= TRUE
;
3059 int sport
,dport
,sserv
,dserv
;
3060 char sports
[256], dports
[256], host
[256];
3064 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3065 /* Add port forwardings. */
3066 ssh
->portfwd_strptr
= cfg
.portfwd
;
3067 while (*ssh
->portfwd_strptr
) {
3068 type
= *ssh
->portfwd_strptr
++;
3070 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t')
3071 sports
[n
++] = *ssh
->portfwd_strptr
++;
3073 if (*ssh
->portfwd_strptr
== '\t')
3074 ssh
->portfwd_strptr
++;
3076 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':')
3077 host
[n
++] = *ssh
->portfwd_strptr
++;
3079 if (*ssh
->portfwd_strptr
== ':')
3080 ssh
->portfwd_strptr
++;
3082 while (*ssh
->portfwd_strptr
)
3083 dports
[n
++] = *ssh
->portfwd_strptr
++;
3085 ssh
->portfwd_strptr
++;
3086 dport
= atoi(dports
);
3090 se
= getservbyname(dports
, NULL
);
3092 dport
= ntohs(se
->s_port
);
3095 "Service lookup failed for destination port \"%s\"",
3100 sport
= atoi(sports
);
3104 se
= getservbyname(sports
, NULL
);
3106 sport
= ntohs(se
->s_port
);
3109 "Service lookup failed for source port \"%s\"",
3114 if (sport
&& dport
) {
3116 pfd_addforward(host
, dport
, sport
);
3117 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3118 " %s:%.*s%.*s%d%.*s",
3119 sserv ?
strlen(sports
) : 0, sports
,
3120 sserv
, "(", sport
, sserv
, ")",
3122 dserv ?
strlen(dports
) : 0, dports
,
3123 dserv
, "(", dport
, dserv
, ")");
3126 struct ssh_rportfwd
*pf
;
3127 pf
= smalloc(sizeof(*pf
));
3128 strcpy(pf
->dhost
, host
);
3130 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3132 "Duplicate remote port forwarding to %s:%d",
3137 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3138 " forward to %s:%.*s%.*s%d%.*s",
3139 sserv ?
strlen(sports
) : 0, sports
,
3140 sserv
, "(", sport
, sserv
, ")",
3142 dserv ?
strlen(dports
) : 0, dports
,
3143 dserv
, "(", dport
, dserv
, ")");
3145 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3153 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3154 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3155 bombout(("Protocol confusion"));
3157 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3158 c_write_str(ssh
, "Server refused port"
3161 logevent("Remote port forwarding enabled");
3169 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
3170 PKT_STR
, cfg
.termtype
,
3171 PKT_INT
, ssh
->term_height
,
3172 PKT_INT
, ssh
->term_width
,
3173 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3174 ssh
->state
= SSH_STATE_INTERMED
;
3178 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3179 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3180 bombout(("Protocol confusion"));
3182 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3183 c_write_str(ssh
, "Server refused to allocate pty\r\n");
3184 ssh
->editing
= ssh
->echoing
= 1;
3186 logevent("Allocated pty");
3188 ssh
->editing
= ssh
->echoing
= 1;
3191 if (cfg
.compression
) {
3192 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3196 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3197 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3198 bombout(("Protocol confusion"));
3200 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3201 c_write_str(ssh
, "Server refused to compress\r\n");
3203 logevent("Started compression");
3204 ssh
->v1_compressing
= TRUE
;
3205 ssh
->cs_comp_ctx
= zlib_compress_init();
3206 logevent("Initialised zlib (RFC1950) compression");
3207 ssh
->sc_comp_ctx
= zlib_decompress_init();
3208 logevent("Initialised zlib (RFC1950) decompression");
3212 * Start the shell or command.
3214 * Special case: if the first-choice command is an SSH2
3215 * subsystem (hence not usable here) and the second choice
3216 * exists, we fall straight back to that.
3219 char *cmd
= cfg
.remote_cmd_ptr
;
3221 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3222 cmd
= cfg
.remote_cmd_ptr2
;
3223 ssh
->fallback_cmd
= TRUE
;
3226 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3228 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3229 logevent("Started session");
3232 ssh
->state
= SSH_STATE_SESSION
;
3233 if (ssh
->size_needed
)
3234 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
3235 if (ssh
->eof_needed
)
3236 ssh_special(ssh
, TS_EOF
);
3239 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
3241 ssh
->channels
= newtree234(ssh_channelcmp
);
3245 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3246 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3247 long len
= GET_32BIT(ssh
->pktin
.body
);
3249 from_backend(ssh
->frontend
,
3250 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3251 ssh
->pktin
.body
+ 4, len
);
3252 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3253 ssh
->v1_stdout_throttling
= 1;
3254 ssh1_throttle(ssh
, +1);
3256 } else if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
3257 ssh
->state
= SSH_STATE_CLOSED
;
3258 logevent("Received disconnect request");
3260 } else if (ssh
->pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3261 /* Remote side is trying to open a channel to talk to our
3262 * X-Server. Give them back a local channel number. */
3263 struct ssh_channel
*c
;
3265 logevent("Received X11 connect request");
3266 /* Refuse if X11 forwarding is disabled. */
3267 if (!ssh
->X11_fwd_enabled
) {
3268 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3269 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3270 logevent("Rejected X11 connect request");
3272 c
= smalloc(sizeof(struct ssh_channel
));
3275 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3276 logevent("opening X11 forward connection failed");
3278 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3279 PKT_INT
, GET_32BIT(ssh
->pktin
.body
),
3283 ("opening X11 forward connection succeeded");
3284 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3285 c
->localid
= alloc_channel_id(ssh
);
3287 c
->v
.v1
.throttling
= 0;
3288 c
->type
= CHAN_X11
; /* identify channel type */
3289 add234(ssh
->channels
, c
);
3290 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3291 PKT_INT
, c
->remoteid
, PKT_INT
,
3292 c
->localid
, PKT_END
);
3293 logevent("Opened X11 forward channel");
3296 } else if (ssh
->pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3297 /* Remote side is trying to open a channel to talk to our
3298 * agent. Give them back a local channel number. */
3299 struct ssh_channel
*c
;
3301 /* Refuse if agent forwarding is disabled. */
3302 if (!ssh
->agentfwd_enabled
) {
3303 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3304 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3306 c
= smalloc(sizeof(struct ssh_channel
));
3308 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3309 c
->localid
= alloc_channel_id(ssh
);
3311 c
->v
.v1
.throttling
= 0;
3312 c
->type
= CHAN_AGENT
; /* identify channel type */
3313 c
->u
.a
.lensofar
= 0;
3314 add234(ssh
->channels
, c
);
3315 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3316 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3319 } else if (ssh
->pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3320 /* Remote side is trying to open a channel to talk to a
3321 * forwarded port. Give them back a local channel number. */
3322 struct ssh_channel
*c
;
3323 struct ssh_rportfwd pf
;
3325 char host
[256], buf
[1024];
3327 c
= smalloc(sizeof(struct ssh_channel
));
3330 hostsize
= GET_32BIT(ssh
->pktin
.body
+4);
3331 for(h
= host
, p
= ssh
->pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3332 if (h
+1 < host
+sizeof(host
))
3337 port
= GET_32BIT(p
);
3339 strcpy(pf
.dhost
, host
);
3342 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3343 sprintf(buf
, "Rejected remote port open request for %s:%d",
3346 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3347 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3349 sprintf(buf
, "Received remote port open request for %s:%d",
3352 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3355 sprintf(buf
, "Port open failed: %s", e
);
3358 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3359 PKT_INT
, GET_32BIT(ssh
->pktin
.body
),
3362 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3363 c
->localid
= alloc_channel_id(ssh
);
3365 c
->v
.v1
.throttling
= 0;
3366 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3367 add234(ssh
->channels
, c
);
3368 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3369 PKT_INT
, c
->remoteid
, PKT_INT
,
3370 c
->localid
, PKT_END
);
3371 logevent("Forwarded port opened successfully");
3375 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3376 unsigned int remoteid
= GET_32BIT(ssh
->pktin
.body
);
3377 unsigned int localid
= GET_32BIT(ssh
->pktin
.body
+4);
3378 struct ssh_channel
*c
;
3380 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3381 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3382 c
->remoteid
= localid
;
3383 c
->type
= CHAN_SOCKDATA
;
3384 c
->v
.v1
.throttling
= 0;
3385 pfd_confirm(c
->u
.pfd
.s
);
3388 if (c
&& c
->closes
) {
3390 * We have a pending close on this channel,
3391 * which we decided on before the server acked
3392 * the channel open. So now we know the
3393 * remoteid, we can close it again.
3395 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3396 PKT_INT
, c
->remoteid
, PKT_END
);
3399 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3400 unsigned int remoteid
= GET_32BIT(ssh
->pktin
.body
);
3401 unsigned int localid
= GET_32BIT(ssh
->pktin
.body
+4);
3402 struct ssh_channel
*c
;
3404 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3405 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3406 logevent("Forwarded connection refused by server");
3407 pfd_close(c
->u
.pfd
.s
);
3408 del234(ssh
->channels
, c
);
3412 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3413 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3414 /* Remote side closes a channel. */
3415 unsigned i
= GET_32BIT(ssh
->pktin
.body
);
3416 struct ssh_channel
*c
;
3417 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3418 if (c
&& ((int)c
->remoteid
) != -1) {
3421 (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3423 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3424 logevent("Forwarded X11 connection terminated");
3425 assert(c
->u
.x11
.s
!= NULL
);
3426 x11_close(c
->u
.x11
.s
);
3429 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3430 logevent("Forwarded port closed");
3431 assert(c
->u
.pfd
.s
!= NULL
);
3432 pfd_close(c
->u
.pfd
.s
);
3436 c
->closes
|= (closetype
<< 2); /* seen this message */
3437 if (!(c
->closes
& closetype
)) {
3438 send_packet(ssh
, ssh
->pktin
.type
, PKT_INT
, c
->remoteid
,
3440 c
->closes
|= closetype
; /* sent it too */
3443 if (c
->closes
== 15) {
3444 del234(ssh
->channels
, c
);
3448 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3449 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3450 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3453 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3454 /* Data sent down one of our channels. */
3455 int i
= GET_32BIT(ssh
->pktin
.body
);
3456 int len
= GET_32BIT(ssh
->pktin
.body
+ 4);
3457 unsigned char *p
= ssh
->pktin
.body
+ 8;
3458 struct ssh_channel
*c
;
3459 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3464 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3467 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3470 /* Data for an agent message. Buffer it. */
3472 if (c
->u
.a
.lensofar
< 4) {
3473 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3474 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3478 c
->u
.a
.lensofar
+= l
;
3480 if (c
->u
.a
.lensofar
== 4) {
3482 4 + GET_32BIT(c
->u
.a
.msglen
);
3483 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3484 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3486 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3488 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3490 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3494 c
->u
.a
.lensofar
+= l
;
3496 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3497 void *reply
, *sentreply
;
3499 agent_query(c
->u
.a
.message
,
3500 c
->u
.a
.totallen
, &reply
,
3505 /* Fake SSH_AGENT_FAILURE. */
3506 sentreply
= "\0\0\0\1\5";
3509 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3510 PKT_INT
, c
->remoteid
,
3512 PKT_DATA
, sentreply
, replylen
,
3516 sfree(c
->u
.a
.message
);
3517 c
->u
.a
.lensofar
= 0;
3520 bufsize
= 0; /* agent channels never back up */
3523 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3524 c
->v
.v1
.throttling
= 1;
3525 ssh1_throttle(ssh
, +1);
3528 } else if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
3529 /* may be from EXEC_SHELL on some servers */
3530 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3531 /* may be from EXEC_SHELL on some servers
3532 * if no pty is available or in other odd cases. Ignore */
3533 } else if (ssh
->pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3535 ssh
->exitcode
= GET_32BIT(ssh
->pktin
.body
);
3536 sprintf(buf
, "Server sent command exit status %d",
3539 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3541 * In case `helpful' firewalls or proxies tack
3542 * extra human-readable text on the end of the
3543 * session which we might mistake for another
3544 * encrypted packet, we close the session once
3545 * we've sent EXIT_CONFIRMATION.
3547 ssh
->state
= SSH_STATE_CLOSED
;
3550 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
3555 int len
= min(inlen
, 512);
3556 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
,
3557 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3568 * Utility routine for decoding comma-separated strings in KEXINIT.
3570 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3572 int needlen
= strlen(needle
);
3575 * Is it at the start of the string?
3577 if (haylen
>= needlen
&& /* haystack is long enough */
3578 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3579 (haylen
== needlen
|| haystack
[needlen
] == ',')
3580 /* either , or EOS follows */
3584 * If not, search for the next comma and resume after that.
3585 * If no comma found, terminate.
3587 while (haylen
> 0 && *haystack
!= ',')
3588 haylen
--, haystack
++;
3591 haylen
--, haystack
++; /* skip over comma itself */
3596 * SSH2 key creation method.
3598 static void ssh2_mkkey(Ssh ssh
, Bignum K
, char *H
, char *sessid
, char chr
,
3602 /* First 20 bytes. */
3604 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3606 SHA_Bytes(&s
, H
, 20);
3607 SHA_Bytes(&s
, &chr
, 1);
3608 SHA_Bytes(&s
, sessid
, 20);
3609 SHA_Final(&s
, keyspace
);
3610 /* Next 20 bytes. */
3612 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3614 SHA_Bytes(&s
, H
, 20);
3615 SHA_Bytes(&s
, keyspace
, 20);
3616 SHA_Final(&s
, keyspace
+ 20);
3620 * Handle the SSH2 transport layer.
3622 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3624 struct do_ssh2_transport_state
{
3625 int nbits
, pbits
, warn
;
3626 Bignum p
, g
, e
, f
, K
;
3627 int kex_init_value
, kex_reply_value
;
3628 const struct ssh_mac
**maclist
;
3630 const struct ssh2_cipher
*cscipher_tobe
;
3631 const struct ssh2_cipher
*sccipher_tobe
;
3632 const struct ssh_mac
*csmac_tobe
;
3633 const struct ssh_mac
*scmac_tobe
;
3634 const struct ssh_compress
*cscomp_tobe
;
3635 const struct ssh_compress
*sccomp_tobe
;
3636 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3637 int hostkeylen
, siglen
;
3638 void *hkey
; /* actual host key */
3639 unsigned char exchange_hash
[20];
3640 int n_preferred_ciphers
;
3641 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3642 const struct ssh_compress
*preferred_comp
;
3645 crState(do_ssh2_transport_state
);
3647 crBegin(ssh
->do_ssh2_transport_crstate
);
3649 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
3650 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
3651 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
3659 * Set up the preferred ciphers. (NULL => warn below here)
3661 s
->n_preferred_ciphers
= 0;
3662 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3663 switch (cfg
.ssh_cipherlist
[i
]) {
3664 case CIPHER_BLOWFISH
:
3665 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
3668 if (cfg
.ssh2_des_cbc
) {
3669 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
3673 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
3676 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
3679 /* Flag for later. Don't bother if it's the last in
3681 if (i
< CIPHER_MAX
- 1) {
3682 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
3690 * Set up preferred compression.
3692 if (cfg
.compression
)
3693 s
->preferred_comp
= &ssh_zlib
;
3695 s
->preferred_comp
= &ssh_comp_none
;
3698 * Be prepared to work around the buggy MAC problem.
3700 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
3701 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
3703 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
3707 int i
, j
, cipherstr_started
;
3710 * Construct and send our key exchange packet.
3712 ssh2_pkt_init(ssh
, SSH2_MSG_KEXINIT
);
3713 for (i
= 0; i
< 16; i
++)
3714 ssh2_pkt_addbyte(ssh
, (unsigned char) random_byte());
3715 /* List key exchange algorithms. */
3716 ssh2_pkt_addstring_start(ssh
);
3717 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3718 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3719 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
3721 ssh2_pkt_addstring_str(ssh
, kex_algs
[i
]->name
);
3722 if (i
< lenof(kex_algs
) - 1)
3723 ssh2_pkt_addstring_str(ssh
, ",");
3725 /* List server host key algorithms. */
3726 ssh2_pkt_addstring_start(ssh
);
3727 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3728 ssh2_pkt_addstring_str(ssh
, hostkey_algs
[i
]->name
);
3729 if (i
< lenof(hostkey_algs
) - 1)
3730 ssh2_pkt_addstring_str(ssh
, ",");
3732 /* List client->server encryption algorithms. */
3733 ssh2_pkt_addstring_start(ssh
);
3734 cipherstr_started
= 0;
3735 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3736 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3737 if (!c
) continue; /* warning flag */
3738 for (j
= 0; j
< c
->nciphers
; j
++) {
3739 if (cipherstr_started
)
3740 ssh2_pkt_addstring_str(ssh
, ",");
3741 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
3742 cipherstr_started
= 1;
3745 /* List server->client encryption algorithms. */
3746 ssh2_pkt_addstring_start(ssh
);
3747 cipherstr_started
= 0;
3748 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3749 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3750 if (!c
) continue; /* warning flag */
3751 for (j
= 0; j
< c
->nciphers
; j
++) {
3752 if (cipherstr_started
)
3753 ssh2_pkt_addstring_str(ssh
, ",");
3754 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
3755 cipherstr_started
= 1;
3758 /* List client->server MAC algorithms. */
3759 ssh2_pkt_addstring_start(ssh
);
3760 for (i
= 0; i
< s
->nmacs
; i
++) {
3761 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
3762 if (i
< s
->nmacs
- 1)
3763 ssh2_pkt_addstring_str(ssh
, ",");
3765 /* List server->client MAC algorithms. */
3766 ssh2_pkt_addstring_start(ssh
);
3767 for (i
= 0; i
< s
->nmacs
; i
++) {
3768 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
3769 if (i
< s
->nmacs
- 1)
3770 ssh2_pkt_addstring_str(ssh
, ",");
3772 /* List client->server compression algorithms. */
3773 ssh2_pkt_addstring_start(ssh
);
3774 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3775 const struct ssh_compress
*c
=
3776 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3777 ssh2_pkt_addstring_str(ssh
, c
->name
);
3778 if (i
< lenof(compressions
))
3779 ssh2_pkt_addstring_str(ssh
, ",");
3781 /* List server->client compression algorithms. */
3782 ssh2_pkt_addstring_start(ssh
);
3783 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3784 const struct ssh_compress
*c
=
3785 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3786 ssh2_pkt_addstring_str(ssh
, c
->name
);
3787 if (i
< lenof(compressions
))
3788 ssh2_pkt_addstring_str(ssh
, ",");
3790 /* List client->server languages. Empty list. */
3791 ssh2_pkt_addstring_start(ssh
);
3792 /* List server->client languages. Empty list. */
3793 ssh2_pkt_addstring_start(ssh
);
3794 /* First KEX packet does _not_ follow, because we're not that brave. */
3795 ssh2_pkt_addbool(ssh
, FALSE
);
3797 ssh2_pkt_adduint32(ssh
, 0);
3800 ssh
->exhash
= ssh
->exhashbase
;
3801 sha_string(&ssh
->exhash
, ssh
->pktout
.data
+ 5, ssh
->pktout
.length
- 5);
3807 sha_string(&ssh
->exhash
, ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5);
3810 * Now examine the other side's KEXINIT to see what we're up
3817 if (ssh
->pktin
.type
!= SSH2_MSG_KEXINIT
) {
3818 bombout(("expected key exchange packet from server"));
3822 ssh
->hostkey
= NULL
;
3823 s
->cscipher_tobe
= NULL
;
3824 s
->sccipher_tobe
= NULL
;
3825 s
->csmac_tobe
= NULL
;
3826 s
->scmac_tobe
= NULL
;
3827 s
->cscomp_tobe
= NULL
;
3828 s
->sccomp_tobe
= NULL
;
3829 ssh
->pktin
.savedpos
+= 16; /* skip garbage cookie */
3830 ssh2_pkt_getstring(ssh
, &str
, &len
); /* key exchange algorithms */
3831 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3832 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3833 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
3835 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3836 ssh
->kex
= kex_algs
[i
];
3840 ssh2_pkt_getstring(ssh
, &str
, &len
); /* host key algorithms */
3841 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3842 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3843 ssh
->hostkey
= hostkey_algs
[i
];
3847 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server cipher */
3849 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3850 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3854 for (j
= 0; j
< c
->nciphers
; j
++) {
3855 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3856 s
->cscipher_tobe
= c
->list
[j
];
3861 if (s
->cscipher_tobe
) {
3863 askcipher(s
->cscipher_tobe
->name
, 1);
3867 if (!s
->cscipher_tobe
) {
3868 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3872 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client cipher */
3874 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3875 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3879 for (j
= 0; j
< c
->nciphers
; j
++) {
3880 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3881 s
->sccipher_tobe
= c
->list
[j
];
3886 if (s
->sccipher_tobe
) {
3888 askcipher(s
->sccipher_tobe
->name
, 2);
3892 if (!s
->sccipher_tobe
) {
3893 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3897 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server mac */
3898 for (i
= 0; i
< s
->nmacs
; i
++) {
3899 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
3900 s
->csmac_tobe
= s
->maclist
[i
];
3904 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client mac */
3905 for (i
= 0; i
< s
->nmacs
; i
++) {
3906 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
3907 s
->scmac_tobe
= s
->maclist
[i
];
3911 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server compression */
3912 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3913 const struct ssh_compress
*c
=
3914 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3915 if (in_commasep_string(c
->name
, str
, len
)) {
3920 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client compression */
3921 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3922 const struct ssh_compress
*c
=
3923 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3924 if (in_commasep_string(c
->name
, str
, len
)) {
3932 * Work out the number of bits of key we will need from the key
3933 * exchange. We start with the maximum key length of either
3939 csbits
= s
->cscipher_tobe
->keylen
;
3940 scbits
= s
->sccipher_tobe
->keylen
;
3941 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
3943 /* The keys only have 160-bit entropy, since they're based on
3944 * a SHA-1 hash. So cap the key size at 160 bits. */
3949 * If we're doing Diffie-Hellman group exchange, start by
3950 * requesting a group.
3952 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
3953 logevent("Doing Diffie-Hellman group exchange");
3954 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3956 * Work out how big a DH group we will need to allow that
3959 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
3960 ssh2_pkt_init(ssh
, SSH2_MSG_KEX_DH_GEX_REQUEST
);
3961 ssh2_pkt_adduint32(ssh
, s
->pbits
);
3965 if (ssh
->pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3966 bombout(("expected key exchange group packet from server"));
3969 s
->p
= ssh2_pkt_getmp(ssh
);
3970 s
->g
= ssh2_pkt_getmp(ssh
);
3971 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
3972 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3973 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3975 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3976 ssh
->kex_ctx
= dh_setup_group1();
3977 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3978 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3981 logevent("Doing Diffie-Hellman key exchange");
3983 * Now generate and send e for Diffie-Hellman.
3985 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
3986 ssh2_pkt_init(ssh
, s
->kex_init_value
);
3987 ssh2_pkt_addmp(ssh
, s
->e
);
3991 if (ssh
->pktin
.type
!= s
->kex_reply_value
) {
3992 bombout(("expected key exchange reply packet from server"));
3995 ssh2_pkt_getstring(ssh
, &s
->hostkeydata
, &s
->hostkeylen
);
3996 s
->f
= ssh2_pkt_getmp(ssh
);
3997 ssh2_pkt_getstring(ssh
, &s
->sigdata
, &s
->siglen
);
3999 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4001 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4002 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4003 sha_uint32(&ssh
->exhash
, s
->pbits
);
4004 sha_mpint(&ssh
->exhash
, s
->p
);
4005 sha_mpint(&ssh
->exhash
, s
->g
);
4007 sha_mpint(&ssh
->exhash
, s
->e
);
4008 sha_mpint(&ssh
->exhash
, s
->f
);
4009 sha_mpint(&ssh
->exhash
, s
->K
);
4010 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4012 dh_cleanup(ssh
->kex_ctx
);
4015 debug(("Exchange hash is:\n"));
4016 dmemdump(s
->exchange_hash
, 20);
4019 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4021 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4022 s
->exchange_hash
, 20)) {
4023 bombout(("Server's host key did not match the signature supplied"));
4028 * Authenticate remote host: verify host key. (We've already
4029 * checked the signature of the exchange hash.)
4031 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4032 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4033 verify_ssh_host_key(ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4034 s
->keystr
, s
->fingerprint
);
4035 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4036 logevent("Host key fingerprint is:");
4037 logevent(s
->fingerprint
);
4039 sfree(s
->fingerprint
);
4041 ssh
->hostkey
->freekey(s
->hkey
);
4044 * Send SSH2_MSG_NEWKEYS.
4046 ssh2_pkt_init(ssh
, SSH2_MSG_NEWKEYS
);
4050 * Expect SSH2_MSG_NEWKEYS from server.
4053 if (ssh
->pktin
.type
!= SSH2_MSG_NEWKEYS
) {
4054 bombout(("expected new-keys packet from server"));
4059 * Create and initialise session keys.
4061 if (ssh
->cs_cipher_ctx
)
4062 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4063 ssh
->cscipher
= s
->cscipher_tobe
;
4064 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4066 if (ssh
->sc_cipher_ctx
)
4067 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4068 ssh
->sccipher
= s
->sccipher_tobe
;
4069 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4071 if (ssh
->cs_mac_ctx
)
4072 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4073 ssh
->csmac
= s
->csmac_tobe
;
4074 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4076 if (ssh
->sc_mac_ctx
)
4077 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4078 ssh
->scmac
= s
->scmac_tobe
;
4079 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4081 if (ssh
->cs_comp_ctx
)
4082 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4083 ssh
->cscomp
= s
->cscomp_tobe
;
4084 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4086 if (ssh
->sc_comp_ctx
)
4087 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4088 ssh
->sccomp
= s
->sccomp_tobe
;
4089 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4092 * Set IVs after keys. Here we use the exchange hash from the
4093 * _first_ key exchange.
4096 unsigned char keyspace
[40];
4098 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4099 sizeof(s
->exchange_hash
));
4100 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4101 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4102 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4103 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4104 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4105 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4106 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4107 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4108 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4109 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4110 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4111 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4115 sprintf(buf
, "Initialised %.200s client->server encryption",
4116 ssh
->cscipher
->text_name
);
4118 sprintf(buf
, "Initialised %.200s server->client encryption",
4119 ssh
->sccipher
->text_name
);
4121 if (ssh
->cscomp
->text_name
) {
4122 sprintf(buf
, "Initialised %.200s compression",
4123 ssh
->cscomp
->text_name
);
4126 if (ssh
->sccomp
->text_name
) {
4127 sprintf(buf
, "Initialised %.200s decompression",
4128 ssh
->sccomp
->text_name
);
4135 * If this is the first key exchange phase, we must pass the
4136 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4137 * wants to see it but because it will need time to initialise
4138 * itself before it sees an actual packet. In subsequent key
4139 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4140 * it would only confuse the layer above.
4142 if (!s
->first_kex
) {
4148 * Now we're encrypting. Begin returning 1 to the protocol main
4149 * function so that other things can run on top of the
4150 * transport. If we ever see a KEXINIT, we must go back to the
4153 while (!(ispkt
&& ssh
->pktin
.type
== SSH2_MSG_KEXINIT
)) {
4156 logevent("Server initiated key re-exchange");
4157 goto begin_key_exchange
;
4163 * Add data to an SSH2 channel output buffer.
4165 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4168 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4172 * Attempt to send data on an SSH2 channel.
4174 static int ssh2_try_send(struct ssh_channel
*c
)
4178 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4181 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4182 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4183 len
= c
->v
.v2
.remwindow
;
4184 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4185 len
= c
->v
.v2
.remmaxpkt
;
4186 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_DATA
);
4187 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4188 ssh2_pkt_addstring_start(ssh
);
4189 ssh2_pkt_addstring_data(ssh
, data
, len
);
4191 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4192 c
->v
.v2
.remwindow
-= len
;
4196 * After having sent as much data as we can, return the amount
4199 return bufchain_size(&c
->v
.v2
.outbuffer
);
4203 * Potentially enlarge the window on an SSH2 channel.
4205 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4210 * Never send WINDOW_ADJUST for a channel that the remote side
4211 * already thinks it's closed; there's no point, since it won't
4212 * be sending any more data anyway.
4217 if (newwin
> c
->v
.v2
.locwindow
) {
4218 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4219 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4220 ssh2_pkt_adduint32(ssh
, newwin
- c
->v
.v2
.locwindow
);
4222 c
->v
.v2
.locwindow
= newwin
;
4227 * Handle the SSH2 userauth and connection layers.
4229 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4231 struct do_ssh2_authconn_state
{
4233 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4235 AUTH_KEYBOARD_INTERACTIVE
4239 AUTH_TYPE_PUBLICKEY
,
4240 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4241 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4243 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4244 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4246 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4247 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4248 int kbd_inter_running
;
4250 int num_prompts
, curr_prompt
, echo
;
4255 void *publickey_blob
;
4256 int publickey_bloblen
;
4257 unsigned char request
[5], *response
, *p
;
4261 char *pkblob
, *alg
, *commentp
;
4262 int pklen
, alglen
, commentlen
;
4263 int siglen
, retlen
, len
;
4264 char *q
, *agentreq
, *ret
;
4267 crState(do_ssh2_authconn_state
);
4269 crBegin(ssh
->do_ssh2_authconn_crstate
);
4272 * Request userauth protocol, and await a response to it.
4274 ssh2_pkt_init(ssh
, SSH2_MSG_SERVICE_REQUEST
);
4275 ssh2_pkt_addstring(ssh
, "ssh-userauth");
4277 crWaitUntilV(ispkt
);
4278 if (ssh
->pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4279 bombout(("Server refused user authentication protocol"));
4284 * We repeat this whole loop, including the username prompt,
4285 * until we manage a successful authentication. If the user
4286 * types the wrong _password_, they can be sent back to the
4287 * beginning to try another username, if this is configured on.
4288 * (If they specify a username in the config, they are never
4289 * asked, even if they do give a wrong password.)
4291 * I think this best serves the needs of
4293 * - the people who have no configuration, no keys, and just
4294 * want to try repeated (username,password) pairs until they
4295 * type both correctly
4297 * - people who have keys and configuration but occasionally
4298 * need to fall back to passwords
4300 * - people with a key held in Pageant, who might not have
4301 * logged in to a particular machine before; so they want to
4302 * type a username, and then _either_ their key will be
4303 * accepted, _or_ they will type a password. If they mistype
4304 * the username they will want to be able to get back and
4307 s
->username
[0] = '\0';
4308 s
->got_username
= FALSE
;
4313 if (s
->got_username
&& !cfg
.change_username
) {
4315 * We got a username last time round this loop, and
4316 * with change_username turned off we don't try to get
4319 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4320 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4321 if (!ssh_get_line("login as: ",
4322 s
->username
, sizeof(s
->username
), FALSE
)) {
4324 * get_line failed to get a username.
4327 logevent("No username provided. Abandoning session.");
4328 ssh
->state
= SSH_STATE_CLOSED
;
4332 int ret
; /* need not be saved across crReturn */
4333 c_write_str(ssh
, "login as: ");
4335 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
4337 crWaitUntilV(!ispkt
);
4338 ret
= process_userpass_input(ssh
, in
, inlen
);
4343 c_write_str(ssh
, "\r\n");
4344 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
4347 strncpy(s
->username
, cfg
.username
, sizeof(s
->username
));
4348 s
->username
[sizeof(s
->username
)-1] = '\0';
4349 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4350 sprintf(stuff
, "Using username \"%s\".\r\n", s
->username
);
4351 c_write_str(ssh
, stuff
);
4354 s
->got_username
= TRUE
;
4357 * Send an authentication request using method "none": (a)
4358 * just in case it succeeds, and (b) so that we know what
4359 * authentication methods we can usefully try next.
4361 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4363 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4364 ssh2_pkt_addstring(ssh
, s
->username
);
4365 ssh2_pkt_addstring(ssh
, "ssh-connection");/* service requested */
4366 ssh2_pkt_addstring(ssh
, "none"); /* method */
4368 s
->type
= AUTH_TYPE_NONE
;
4370 s
->we_are_in
= FALSE
;
4372 s
->tried_pubkey_config
= FALSE
;
4373 s
->tried_agent
= FALSE
;
4374 s
->tried_keyb_inter
= FALSE
;
4375 s
->kbd_inter_running
= FALSE
;
4376 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4379 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4380 keytype
= key_type(cfg
.keyfile
);
4381 if (keytype
== SSH_KEYTYPE_SSH2
) {
4383 ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4384 &s
->publickey_bloblen
);
4387 logeventf("Unable to use this key file (%s)",
4388 key_type_to_str(keytype
));
4389 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4390 cfg
.keyfile
, key_type_to_str(keytype
));
4391 c_write_str(ssh
, msgbuf
);
4392 s
->publickey_blob
= NULL
;
4395 s
->publickey_blob
= NULL
;
4399 * Wait for the result of the last authentication request.
4402 crWaitUntilV(ispkt
);
4403 while (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4407 * Don't show the banner if we're operating in
4408 * non-verbose non-interactive mode. (It's probably
4409 * a script, which means nobody will read the
4410 * banner _anyway_, and moreover the printing of
4411 * the banner will screw up processing on the
4412 * output of (say) plink.)
4414 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4415 ssh2_pkt_getstring(ssh
, &banner
, &size
);
4417 c_write_untrusted(ssh
, banner
, size
);
4419 crWaitUntilV(ispkt
);
4421 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4422 logevent("Access granted");
4423 s
->we_are_in
= TRUE
;
4427 if (s
->kbd_inter_running
&&
4428 ssh
->pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4430 * This is either a further set-of-prompts packet
4431 * in keyboard-interactive authentication, or it's
4432 * the same one and we came back here with `gotit'
4433 * set. In the former case, we must reset the
4434 * curr_prompt variable.
4438 } else if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4439 bombout(("Strange packet received during authentication: type %d",
4447 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4448 * we can look at the string in it and know what we can
4449 * helpfully try next.
4451 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4454 ssh2_pkt_getstring(ssh
, &methods
, &methlen
);
4455 s
->kbd_inter_running
= FALSE
;
4456 if (!ssh2_pkt_getbool(ssh
)) {
4458 * We have received an unequivocal Access
4459 * Denied. This can translate to a variety of
4462 * - if we'd just tried "none" authentication,
4463 * it's not worth printing anything at all
4465 * - if we'd just tried a public key _offer_,
4466 * the message should be "Server refused our
4467 * key" (or no message at all if the key
4468 * came from Pageant)
4470 * - if we'd just tried anything else, the
4471 * message really should be "Access denied".
4473 * Additionally, if we'd just tried password
4474 * authentication, we should break out of this
4475 * whole loop so as to go back to the username
4478 if (s
->type
== AUTH_TYPE_NONE
) {
4480 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4481 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4482 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4483 c_write_str(ssh
, "Server refused our key\r\n");
4484 logevent("Server refused public key");
4485 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4486 /* server declined keyboard-interactive; ignore */
4488 c_write_str(ssh
, "Access denied\r\n");
4489 logevent("Access denied");
4490 if (s
->type
== AUTH_TYPE_PASSWORD
) {
4491 s
->we_are_in
= FALSE
;
4496 c_write_str(ssh
, "Further authentication required\r\n");
4497 logevent("Further authentication required");
4501 in_commasep_string("publickey", methods
, methlen
);
4503 in_commasep_string("password", methods
, methlen
);
4504 s
->can_keyb_inter
= cfg
.try_ki_auth
&&
4505 in_commasep_string("keyboard-interactive", methods
, methlen
);
4509 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4512 * Most password/passphrase prompts will be
4513 * non-echoing, so we set this to 0 by default.
4514 * Exception is that some keyboard-interactive prompts
4515 * can be echoing, in which case we'll set this to 1.
4519 if (!s
->method
&& s
->can_pubkey
&&
4520 agent_exists() && !s
->tried_agent
) {
4522 * Attempt public-key authentication using Pageant.
4527 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4528 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4530 s
->tried_agent
= TRUE
;
4532 logevent("Pageant is running. Requesting keys.");
4534 /* Request the keys held by the agent. */
4535 PUT_32BIT(s
->request
, 1);
4536 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4537 agent_query(s
->request
, 5, &r
, &s
->responselen
);
4538 s
->response
= (unsigned char *) r
;
4539 if (s
->response
&& s
->responselen
>= 5 &&
4540 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4541 s
->p
= s
->response
+ 5;
4542 s
->nkeys
= GET_32BIT(s
->p
);
4546 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
4549 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
4554 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
4557 s
->pklen
= GET_32BIT(s
->p
);
4559 if (s
->publickey_blob
&&
4560 s
->pklen
== s
->publickey_bloblen
&&
4561 !memcmp(s
->p
, s
->publickey_blob
,
4562 s
->publickey_bloblen
)) {
4563 logevent("This key matches configured key file");
4564 s
->tried_pubkey_config
= 1;
4568 s
->alglen
= GET_32BIT(s
->pkblob
);
4569 s
->alg
= s
->pkblob
+ 4;
4570 s
->commentlen
= GET_32BIT(s
->p
);
4573 s
->p
+= s
->commentlen
;
4574 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4575 ssh2_pkt_addstring(ssh
, s
->username
);
4576 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4577 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4578 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
4579 ssh2_pkt_addstring_start(ssh
);
4580 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4581 ssh2_pkt_addstring_start(ssh
);
4582 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4585 crWaitUntilV(ispkt
);
4586 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4587 logevent("Key refused");
4591 if (flags
& FLAG_VERBOSE
) {
4592 c_write_str(ssh
, "Authenticating with "
4594 c_write(ssh
, s
->commentp
, s
->commentlen
);
4595 c_write_str(ssh
, "\" from agent\r\n");
4599 * Server is willing to accept the key.
4600 * Construct a SIGN_REQUEST.
4602 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4603 ssh2_pkt_addstring(ssh
, s
->username
);
4604 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4605 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4606 ssh2_pkt_addbool(ssh
, TRUE
);
4607 ssh2_pkt_addstring_start(ssh
);
4608 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4609 ssh2_pkt_addstring_start(ssh
);
4610 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4612 s
->siglen
= ssh
->pktout
.length
- 5 + 4 + 20;
4613 s
->len
= 1; /* message type */
4614 s
->len
+= 4 + s
->pklen
; /* key blob */
4615 s
->len
+= 4 + s
->siglen
; /* data to sign */
4616 s
->len
+= 4; /* flags */
4617 s
->agentreq
= smalloc(4 + s
->len
);
4618 PUT_32BIT(s
->agentreq
, s
->len
);
4619 s
->q
= s
->agentreq
+ 4;
4620 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4621 PUT_32BIT(s
->q
, s
->pklen
);
4623 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
4625 PUT_32BIT(s
->q
, s
->siglen
);
4627 /* Now the data to be signed... */
4628 PUT_32BIT(s
->q
, 20);
4630 memcpy(s
->q
, ssh
->v2_session_id
, 20);
4632 memcpy(s
->q
, ssh
->pktout
.data
+ 5,
4633 ssh
->pktout
.length
- 5);
4634 s
->q
+= ssh
->pktout
.length
- 5;
4635 /* And finally the (zero) flags word. */
4637 agent_query(s
->agentreq
, s
->len
+ 4, &vret
, &s
->retlen
);
4641 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4642 logevent("Sending Pageant's response");
4643 ssh2_add_sigblob(ssh
, s
->pkblob
, s
->pklen
,
4645 GET_32BIT(s
->ret
+ 5));
4651 ("Pageant failed to answer challenge");
4661 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
4662 && !s
->tried_pubkey_config
) {
4663 unsigned char *pub_blob
;
4664 char *algorithm
, *comment
;
4667 s
->tried_pubkey_config
= TRUE
;
4669 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4670 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4673 * Try the public key supplied in the configuration.
4675 * First, offer the public blob to see if the server is
4676 * willing to accept it.
4678 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4681 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4682 ssh2_pkt_addstring(ssh
, s
->username
);
4683 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4684 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4685 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
4686 ssh2_pkt_addstring(ssh
, algorithm
);
4687 ssh2_pkt_addstring_start(ssh
);
4688 ssh2_pkt_addstring_data(ssh
, pub_blob
, pub_blob_len
);
4690 logevent("Offered public key"); /* FIXME */
4692 crWaitUntilV(ispkt
);
4693 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4695 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4696 continue; /* key refused; give up on it */
4699 logevent("Offer of public key accepted");
4701 * Actually attempt a serious authentication using
4704 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4705 sprintf(s
->pwprompt
,
4706 "Passphrase for key \"%.100s\": ",
4712 c_write_str(ssh
, "Authenticating with public key \"");
4713 c_write_str(ssh
, comment
);
4714 c_write_str(ssh
, "\"\r\n");
4715 s
->method
= AUTH_PUBLICKEY_FILE
;
4719 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
4720 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
4721 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4722 s
->tried_keyb_inter
= TRUE
;
4724 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4725 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4727 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4728 ssh2_pkt_addstring(ssh
, s
->username
);
4729 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4730 ssh2_pkt_addstring(ssh
, "keyboard-interactive"); /* method */
4731 ssh2_pkt_addstring(ssh
, ""); /* lang */
4732 ssh2_pkt_addstring(ssh
, "");
4735 crWaitUntilV(ispkt
);
4736 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4737 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4739 logevent("Keyboard-interactive authentication refused");
4740 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4744 s
->kbd_inter_running
= TRUE
;
4748 if (s
->kbd_inter_running
) {
4749 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
4750 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4751 s
->tried_keyb_inter
= TRUE
;
4753 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4754 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4756 if (s
->curr_prompt
== 0) {
4758 * We've got a fresh USERAUTH_INFO_REQUEST.
4759 * Display header data, and start going through
4762 char *name
, *inst
, *lang
;
4763 int name_len
, inst_len
, lang_len
;
4765 ssh2_pkt_getstring(ssh
, &name
, &name_len
);
4766 ssh2_pkt_getstring(ssh
, &inst
, &inst_len
);
4767 ssh2_pkt_getstring(ssh
, &lang
, &lang_len
);
4769 c_write_untrusted(ssh
, name
, name_len
);
4770 c_write_str(ssh
, "\r\n");
4773 c_write_untrusted(ssh
, inst
, inst_len
);
4774 c_write_str(ssh
, "\r\n");
4776 s
->num_prompts
= ssh2_pkt_getuint32(ssh
);
4780 * If there are prompts remaining in the packet,
4781 * display one and get a response.
4783 if (s
->curr_prompt
< s
->num_prompts
) {
4787 ssh2_pkt_getstring(ssh
, &prompt
, &prompt_len
);
4788 if (prompt_len
> 0) {
4789 strncpy(s
->pwprompt
, prompt
, sizeof(s
->pwprompt
));
4790 s
->pwprompt
[prompt_len
< sizeof(s
->pwprompt
) ?
4791 prompt_len
: sizeof(s
->pwprompt
)-1] = '\0';
4794 "<server failed to send prompt>: ");
4796 s
->echo
= ssh2_pkt_getbool(ssh
);
4802 if (!s
->method
&& s
->can_passwd
) {
4803 s
->method
= AUTH_PASSWORD
;
4804 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4805 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4806 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
4813 if (!ssh_get_line(s
->pwprompt
, s
->password
,
4814 sizeof(s
->password
), TRUE
)) {
4816 * get_line failed to get a password (for
4817 * example because one was supplied on the
4818 * command line which has already failed to
4821 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
4822 ssh2_pkt_adduint32(ssh
,SSH2_DISCONNECT_BY_APPLICATION
);
4823 ssh2_pkt_addstring(ssh
, "No more passwords available"
4825 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
4827 logevent("Unable to authenticate");
4828 connection_fatal("Unable to authenticate");
4829 ssh
->state
= SSH_STATE_CLOSED
;
4833 int ret
; /* need not be saved across crReturn */
4834 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
4837 setup_userpass_input(ssh
, s
->password
,
4838 sizeof(s
->password
), s
->echo
);
4840 crWaitUntilV(!ispkt
);
4841 ret
= process_userpass_input(ssh
, in
, inlen
);
4845 c_write_str(ssh
, "\r\n");
4849 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
4851 * We have our passphrase. Now try the actual authentication.
4853 struct ssh2_userkey
*key
;
4855 key
= ssh2_load_userkey(cfg
.keyfile
, s
->password
);
4856 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4857 if (key
== SSH2_WRONG_PASSPHRASE
) {
4858 c_write_str(ssh
, "Wrong passphrase\r\n");
4859 s
->tried_pubkey_config
= FALSE
;
4861 c_write_str(ssh
, "Unable to load private key\r\n");
4862 s
->tried_pubkey_config
= TRUE
;
4864 /* Send a spurious AUTH_NONE to return to the top. */
4865 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4866 ssh2_pkt_addstring(ssh
, s
->username
);
4867 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4868 ssh2_pkt_addstring(ssh
, "none"); /* method */
4870 s
->type
= AUTH_TYPE_NONE
;
4872 unsigned char *pkblob
, *sigblob
, *sigdata
;
4873 int pkblob_len
, sigblob_len
, sigdata_len
;
4876 * We have loaded the private key and the server
4877 * has announced that it's willing to accept it.
4878 * Hallelujah. Generate a signature and send it.
4880 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4881 ssh2_pkt_addstring(ssh
, s
->username
);
4882 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4883 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4884 ssh2_pkt_addbool(ssh
, TRUE
);
4885 ssh2_pkt_addstring(ssh
, key
->alg
->name
);
4886 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4887 ssh2_pkt_addstring_start(ssh
);
4888 ssh2_pkt_addstring_data(ssh
, pkblob
, pkblob_len
);
4891 * The data to be signed is:
4895 * followed by everything so far placed in the
4898 sigdata_len
= ssh
->pktout
.length
- 5 + 4 + 20;
4899 sigdata
= smalloc(sigdata_len
);
4900 PUT_32BIT(sigdata
, 20);
4901 memcpy(sigdata
+ 4, ssh
->v2_session_id
, 20);
4902 memcpy(sigdata
+ 24, ssh
->pktout
.data
+ 5,
4903 ssh
->pktout
.length
- 5);
4904 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4905 sigdata_len
, &sigblob_len
);
4906 ssh2_add_sigblob(ssh
, pkblob
, pkblob_len
,
4907 sigblob
, sigblob_len
);
4913 s
->type
= AUTH_TYPE_PUBLICKEY
;
4915 } else if (s
->method
== AUTH_PASSWORD
) {
4917 * We send the password packet lumped tightly together with
4918 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4919 * string long enough to make the total length of the two
4920 * packets constant. This should ensure that a passive
4921 * listener doing traffic analyis can't work out the length
4924 * For this to work, we need an assumption about the
4925 * maximum length of the password packet. I think 256 is
4926 * pretty conservative. Anyone using a password longer than
4927 * that probably doesn't have much to worry about from
4928 * people who find out how long their password is!
4930 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4931 ssh2_pkt_addstring(ssh
, s
->username
);
4932 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4933 ssh2_pkt_addstring(ssh
, "password");
4934 ssh2_pkt_addbool(ssh
, FALSE
);
4935 ssh2_pkt_addstring(ssh
, s
->password
);
4936 ssh2_pkt_defer(ssh
);
4938 * We'll include a string that's an exact multiple of the
4939 * cipher block size. If the cipher is NULL for some
4940 * reason, we don't do this trick at all because we gain
4943 if (ssh
->cscipher
) {
4946 stringlen
= (256 - ssh
->deferred_len
);
4947 stringlen
+= ssh
->cscipher
->blksize
- 1;
4948 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
4951 * Temporarily disable actual compression,
4952 * so we can guarantee to get this string
4953 * exactly the length we want it. The
4954 * compression-disabling routine should
4955 * return an integer indicating how many
4956 * bytes we should adjust our string length
4960 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
4962 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
4963 ssh2_pkt_addstring_start(ssh
);
4964 for (i
= 0; i
< stringlen
; i
++) {
4965 char c
= (char) random_byte();
4966 ssh2_pkt_addstring_data(ssh
, &c
, 1);
4968 ssh2_pkt_defer(ssh
);
4970 ssh_pkt_defersend(ssh
);
4971 logevent("Sent password");
4972 s
->type
= AUTH_TYPE_PASSWORD
;
4973 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
4974 if (s
->curr_prompt
== 0) {
4975 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4976 ssh2_pkt_adduint32(ssh
, s
->num_prompts
);
4978 if (s
->need_pw
) { /* only add pw if we just got one! */
4979 ssh2_pkt_addstring(ssh
, s
->password
);
4980 memset(s
->password
, 0, sizeof(s
->password
));
4983 if (s
->curr_prompt
>= s
->num_prompts
) {
4987 * If there are prompts remaining, we set
4988 * `gotit' so that we won't attempt to get
4989 * another packet. Then we go back round the
4990 * loop and will end up retrieving another
4991 * prompt out of the existing packet. Funky or
4996 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4998 c_write_str(ssh
, "No supported authentication methods"
4999 " left to try!\r\n");
5000 logevent("No supported authentications offered."
5002 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5003 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5004 ssh2_pkt_addstring(ssh
, "No supported authentication"
5005 " methods available");
5006 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5008 ssh
->state
= SSH_STATE_CLOSED
;
5012 } while (!s
->we_are_in
);
5015 * Now we're authenticated for the connection protocol. The
5016 * connection protocol will automatically have started at this
5017 * point; there's no need to send SERVICE_REQUEST.
5021 * So now create a channel with a session in it.
5023 ssh
->channels
= newtree234(ssh_channelcmp
);
5024 ssh
->mainchan
= smalloc(sizeof(struct ssh_channel
));
5025 ssh
->mainchan
->ssh
= ssh
;
5026 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
5027 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
5028 ssh2_pkt_addstring(ssh
, "session");
5029 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->localid
);
5030 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5031 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
5032 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5034 crWaitUntilV(ispkt
);
5035 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5036 bombout(("Server refused to open a session"));
5038 /* FIXME: error data comes back in FAILURE packet */
5040 if (ssh2_pkt_getuint32(ssh
) != ssh
->mainchan
->localid
) {
5041 bombout(("Server's channel confirmation cited wrong channel"));
5044 ssh
->mainchan
->remoteid
= ssh2_pkt_getuint32(ssh
);
5045 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
5046 ssh
->mainchan
->closes
= 0;
5047 ssh
->mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32(ssh
);
5048 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32(ssh
);
5049 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
5050 add234(ssh
->channels
, ssh
->mainchan
);
5051 logevent("Opened channel for session");
5054 * Potentially enable X11 forwarding.
5056 if (cfg
.x11_forward
) {
5057 char proto
[20], data
[64];
5058 logevent("Requesting X11 forwarding");
5059 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
5060 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5061 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5062 ssh2_pkt_addstring(ssh
, "x11-req");
5063 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5064 ssh2_pkt_addbool(ssh
, 0); /* many connections */
5065 ssh2_pkt_addstring(ssh
, proto
);
5066 ssh2_pkt_addstring(ssh
, data
);
5067 ssh2_pkt_adduint32(ssh
, 0); /* screen number */
5071 crWaitUntilV(ispkt
);
5072 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5073 unsigned i
= ssh2_pkt_getuint32(ssh
);
5074 struct ssh_channel
*c
;
5075 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5077 continue; /* nonexistent channel */
5078 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5080 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5082 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5083 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5084 bombout(("Unexpected response to X11 forwarding request:"
5085 " packet type %d", ssh
->pktin
.type
));
5088 logevent("X11 forwarding refused");
5090 logevent("X11 forwarding enabled");
5091 ssh
->X11_fwd_enabled
= TRUE
;
5096 * Enable port forwardings.
5101 int sport
,dport
,sserv
,dserv
;
5102 char sports
[256], dports
[256], host
[256];
5106 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
5107 /* Add port forwardings. */
5108 ssh
->portfwd_strptr
= cfg
.portfwd
;
5109 while (*ssh
->portfwd_strptr
) {
5110 type
= *ssh
->portfwd_strptr
++;
5112 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t')
5113 sports
[n
++] = *ssh
->portfwd_strptr
++;
5115 if (*ssh
->portfwd_strptr
== '\t')
5116 ssh
->portfwd_strptr
++;
5118 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':')
5119 host
[n
++] = *ssh
->portfwd_strptr
++;
5121 if (*ssh
->portfwd_strptr
== ':')
5122 ssh
->portfwd_strptr
++;
5124 while (*ssh
->portfwd_strptr
)
5125 dports
[n
++] = *ssh
->portfwd_strptr
++;
5127 ssh
->portfwd_strptr
++;
5128 dport
= atoi(dports
);
5132 se
= getservbyname(dports
, NULL
);
5134 dport
= ntohs(se
->s_port
);
5137 "Service lookup failed for destination port \"%s\"",
5142 sport
= atoi(sports
);
5146 se
= getservbyname(sports
, NULL
);
5148 sport
= ntohs(se
->s_port
);
5151 "Service lookup failed for source port \"%s\"",
5156 if (sport
&& dport
) {
5158 pfd_addforward(host
, dport
, sport
);
5159 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
5160 " %s:%.*s%.*s%d%.*s",
5161 sserv ?
strlen(sports
) : 0, sports
,
5162 sserv
, "(", sport
, sserv
, ")",
5164 dserv ?
strlen(dports
) : 0, dports
,
5165 dserv
, "(", dport
, dserv
, ")");
5168 struct ssh_rportfwd
*pf
;
5169 pf
= smalloc(sizeof(*pf
));
5170 strcpy(pf
->dhost
, host
);
5173 if (add234(ssh
->rportfwds
, pf
) != pf
) {
5175 "Duplicate remote port forwarding to %s:%d",
5180 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
5181 " forward to %s:%.*s%.*s%d%.*s",
5182 sserv ?
strlen(sports
) : 0, sports
,
5183 sserv
, "(", sport
, sserv
, ")",
5185 dserv ?
strlen(dports
) : 0, dports
,
5186 dserv
, "(", dport
, dserv
, ")");
5188 ssh2_pkt_init(ssh
, SSH2_MSG_GLOBAL_REQUEST
);
5189 ssh2_pkt_addstring(ssh
, "tcpip-forward");
5190 ssh2_pkt_addbool(ssh
, 1);/* want reply */
5191 if (cfg
.rport_acceptall
)
5192 ssh2_pkt_addstring(ssh
, "0.0.0.0");
5194 ssh2_pkt_addstring(ssh
, "127.0.0.1");
5195 ssh2_pkt_adduint32(ssh
, sport
);
5199 crWaitUntilV(ispkt
);
5200 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5201 unsigned i
= ssh2_pkt_getuint32(ssh
);
5202 struct ssh_channel
*c
;
5203 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5205 continue;/* nonexistent channel */
5206 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5208 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5210 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5211 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5212 bombout(("Unexpected response to port "
5213 "forwarding request: packet type %d",
5217 logevent("Server refused this port forwarding");
5219 logevent("Remote port forwarding enabled");
5228 * Potentially enable agent forwarding.
5230 if (cfg
.agentfwd
&& agent_exists()) {
5231 logevent("Requesting OpenSSH-style agent forwarding");
5232 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5233 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5234 ssh2_pkt_addstring(ssh
, "auth-agent-req@openssh.com");
5235 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5239 crWaitUntilV(ispkt
);
5240 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5241 unsigned i
= ssh2_pkt_getuint32(ssh
);
5242 struct ssh_channel
*c
;
5243 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5245 continue; /* nonexistent channel */
5246 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5248 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5250 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5251 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5252 bombout(("Unexpected response to agent forwarding request:"
5253 " packet type %d", ssh
->pktin
.type
));
5256 logevent("Agent forwarding refused");
5258 logevent("Agent forwarding enabled");
5259 ssh
->agentfwd_enabled
= TRUE
;
5264 * Now allocate a pty for the session.
5267 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5268 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5269 ssh2_pkt_addstring(ssh
, "pty-req");
5270 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5271 ssh2_pkt_addstring(ssh
, cfg
.termtype
);
5272 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5273 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5274 ssh2_pkt_adduint32(ssh
, 0); /* pixel width */
5275 ssh2_pkt_adduint32(ssh
, 0); /* pixel height */
5276 ssh2_pkt_addstring_start(ssh
);
5277 ssh2_pkt_addstring_data(ssh
, "\0", 1); /* TTY_OP_END, no special options */
5279 ssh
->state
= SSH_STATE_INTERMED
;
5282 crWaitUntilV(ispkt
);
5283 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5284 unsigned i
= ssh2_pkt_getuint32(ssh
);
5285 struct ssh_channel
*c
;
5286 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5288 continue; /* nonexistent channel */
5289 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5291 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5293 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5294 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5295 bombout(("Unexpected response to pty request:"
5296 " packet type %d", ssh
->pktin
.type
));
5299 c_write_str(ssh
, "Server refused to allocate pty\r\n");
5300 ssh
->editing
= ssh
->echoing
= 1;
5302 logevent("Allocated pty");
5305 ssh
->editing
= ssh
->echoing
= 1;
5309 * Start a shell or a remote command. We may have to attempt
5310 * this twice if the config data has provided a second choice
5317 if (ssh
->fallback_cmd
) {
5318 subsys
= cfg
.ssh_subsys2
;
5319 cmd
= cfg
.remote_cmd_ptr2
;
5321 subsys
= cfg
.ssh_subsys
;
5322 cmd
= cfg
.remote_cmd_ptr
;
5325 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5326 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5328 ssh2_pkt_addstring(ssh
, "subsystem");
5329 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5330 ssh2_pkt_addstring(ssh
, cmd
);
5332 ssh2_pkt_addstring(ssh
, "exec");
5333 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5334 ssh2_pkt_addstring(ssh
, cmd
);
5336 ssh2_pkt_addstring(ssh
, "shell");
5337 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5341 crWaitUntilV(ispkt
);
5342 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5343 unsigned i
= ssh2_pkt_getuint32(ssh
);
5344 struct ssh_channel
*c
;
5345 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5347 continue; /* nonexistent channel */
5348 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5350 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5351 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5352 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5353 bombout(("Unexpected response to shell/command request:"
5354 " packet type %d", ssh
->pktin
.type
));
5358 * We failed to start the command. If this is the
5359 * fallback command, we really are finished; if it's
5360 * not, and if the fallback command exists, try falling
5361 * back to it before complaining.
5363 if (!ssh
->fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5364 logevent("Primary command failed; attempting fallback");
5365 ssh
->fallback_cmd
= TRUE
;
5368 bombout(("Server refused to start a shell/command"));
5371 logevent("Started a shell/command");
5376 ssh
->state
= SSH_STATE_SESSION
;
5377 if (ssh
->size_needed
)
5378 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
5379 if (ssh
->eof_needed
)
5380 ssh_special(ssh
, TS_EOF
);
5386 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
5390 s
->try_send
= FALSE
;
5392 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5393 ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5396 unsigned i
= ssh2_pkt_getuint32(ssh
);
5397 struct ssh_channel
*c
;
5398 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5400 continue; /* nonexistent channel */
5401 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5402 ssh2_pkt_getuint32(ssh
) != SSH2_EXTENDED_DATA_STDERR
)
5403 continue; /* extended but not stderr */
5404 ssh2_pkt_getstring(ssh
, &data
, &length
);
5407 c
->v
.v2
.locwindow
-= length
;
5409 case CHAN_MAINSESSION
:
5411 from_backend(ssh
->frontend
, ssh
->pktin
.type
==
5412 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5416 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5419 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5422 while (length
> 0) {
5423 if (c
->u
.a
.lensofar
< 4) {
5424 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5425 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5429 c
->u
.a
.lensofar
+= l
;
5431 if (c
->u
.a
.lensofar
== 4) {
5433 4 + GET_32BIT(c
->u
.a
.msglen
);
5434 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5435 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5437 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5439 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5441 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5445 c
->u
.a
.lensofar
+= l
;
5447 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5448 void *reply
, *sentreply
;
5450 agent_query(c
->u
.a
.message
,
5451 c
->u
.a
.totallen
, &reply
,
5456 /* Fake SSH_AGENT_FAILURE. */
5457 sentreply
= "\0\0\0\1\5";
5460 ssh2_add_channel_data(c
, sentreply
, replylen
);
5464 sfree(c
->u
.a
.message
);
5465 c
->u
.a
.lensofar
= 0;
5472 * If we are not buffering too much data,
5473 * enlarge the window again at the remote side.
5475 if (bufsize
< OUR_V2_WINSIZE
)
5476 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5478 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5479 unsigned i
= ssh2_pkt_getuint32(ssh
);
5480 struct ssh_channel
*c
;
5482 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5484 continue; /* nonexistent channel */
5486 if (c
->type
== CHAN_X11
) {
5488 * Remote EOF on an X11 channel means we should
5489 * wrap up and close the channel ourselves.
5491 x11_close(c
->u
.x11
.s
);
5493 } else if (c
->type
== CHAN_AGENT
) {
5495 } else if (c
->type
== CHAN_SOCKDATA
) {
5496 pfd_close(c
->u
.pfd
.s
);
5499 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5500 unsigned i
= ssh2_pkt_getuint32(ssh
);
5501 struct ssh_channel
*c
;
5503 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5504 if (!c
|| ((int)c
->remoteid
) == -1) {
5505 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5506 c ?
"half-open" : "nonexistent", i
));
5508 /* Do pre-close processing on the channel. */
5510 case CHAN_MAINSESSION
:
5511 break; /* nothing to see here, move along */
5513 if (c
->u
.x11
.s
!= NULL
)
5514 x11_close(c
->u
.x11
.s
);
5521 if (c
->u
.pfd
.s
!= NULL
)
5522 pfd_close(c
->u
.pfd
.s
);
5526 if (c
->closes
== 0) {
5527 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
5528 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5531 del234(ssh
->channels
, c
);
5532 bufchain_clear(&c
->v
.v2
.outbuffer
);
5536 * See if that was the last channel left open.
5538 if (count234(ssh
->channels
) == 0) {
5541 * We used to send SSH_MSG_DISCONNECT here,
5542 * because I'd believed that _every_ conforming
5543 * SSH2 connection had to end with a disconnect
5544 * being sent by at least one side; apparently
5545 * I was wrong and it's perfectly OK to
5546 * unceremoniously slam the connection shut
5547 * when you're done, and indeed OpenSSH feels
5548 * this is more polite than sending a
5549 * DISCONNECT. So now we don't.
5551 logevent("All channels closed. Disconnecting");
5552 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5553 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5554 ssh2_pkt_addstring(ssh
, "All open channels closed");
5555 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5558 ssh
->state
= SSH_STATE_CLOSED
;
5561 continue; /* remote sends close; ignore (FIXME) */
5562 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5563 unsigned i
= ssh2_pkt_getuint32(ssh
);
5564 struct ssh_channel
*c
;
5565 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5567 continue; /* nonexistent channel */
5568 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5570 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5571 unsigned i
= ssh2_pkt_getuint32(ssh
);
5572 struct ssh_channel
*c
;
5573 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5575 continue; /* nonexistent channel */
5576 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5577 continue; /* dunno why they're confirming this */
5578 c
->remoteid
= ssh2_pkt_getuint32(ssh
);
5579 c
->type
= CHAN_SOCKDATA
;
5580 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32(ssh
);
5581 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32(ssh
);
5583 pfd_confirm(c
->u
.pfd
.s
);
5586 * We have a pending close on this channel,
5587 * which we decided on before the server acked
5588 * the channel open. So now we know the
5589 * remoteid, we can close it again.
5591 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
5592 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5595 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5596 unsigned i
= ssh2_pkt_getuint32(ssh
);
5597 struct ssh_channel
*c
;
5598 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5600 continue; /* nonexistent channel */
5601 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5602 continue; /* dunno why they're failing this */
5604 logevent("Forwarded connection refused by server");
5606 pfd_close(c
->u
.pfd
.s
);
5608 del234(ssh
->channels
, c
);
5610 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5613 int typelen
, want_reply
;
5614 struct ssh_channel
*c
;
5616 localid
= ssh2_pkt_getuint32(ssh
);
5617 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5618 want_reply
= ssh2_pkt_getbool(ssh
);
5621 * First, check that the channel exists. Otherwise,
5622 * we can instantly disconnect with a rude message.
5624 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5627 sprintf(buf
, "Received channel request for nonexistent"
5628 " channel %d", localid
);
5630 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5631 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5632 ssh2_pkt_addstring(ssh
, buf
);
5633 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5635 connection_fatal("%s", buf
);
5636 ssh
->state
= SSH_STATE_CLOSED
;
5641 * Having got the channel number, we now look at
5642 * the request type string to see if it's something
5645 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5646 c
== ssh
->mainchan
) {
5647 /* We recognise "exit-status" on the primary channel. */
5649 ssh
->exitcode
= ssh2_pkt_getuint32(ssh
);
5650 sprintf(buf
, "Server sent command exit status %d",
5654 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_SUCCESS
);
5655 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5660 * This is a channel request we don't know
5661 * about, so we now either ignore the request
5662 * or respond with CHANNEL_FAILURE, depending
5666 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_FAILURE
);
5667 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5671 } else if (ssh
->pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5673 int typelen
, want_reply
;
5675 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5676 want_reply
= ssh2_pkt_getbool(ssh
);
5679 * We currently don't support any global requests
5680 * at all, so we either ignore the request or
5681 * respond with REQUEST_FAILURE, depending on
5685 ssh2_pkt_init(ssh
, SSH2_MSG_REQUEST_FAILURE
);
5688 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5692 struct ssh_channel
*c
;
5693 unsigned remid
, winsize
, pktsize
;
5694 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5695 c
= smalloc(sizeof(struct ssh_channel
));
5698 remid
= ssh2_pkt_getuint32(ssh
);
5699 winsize
= ssh2_pkt_getuint32(ssh
);
5700 pktsize
= ssh2_pkt_getuint32(ssh
);
5702 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5703 if (!ssh
->X11_fwd_enabled
)
5704 error
= "X11 forwarding is not enabled";
5705 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5707 error
= "Unable to open an X11 connection";
5711 } else if (typelen
== 15 &&
5712 !memcmp(type
, "forwarded-tcpip", 15)) {
5713 struct ssh_rportfwd pf
, *realpf
;
5716 ssh2_pkt_getstring(ssh
, &dummy
, &dummylen
);/* skip address */
5717 pf
.sport
= ssh2_pkt_getuint32(ssh
);
5718 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5719 if (realpf
== NULL
) {
5720 error
= "Remote port is not recognised";
5722 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5725 sprintf(buf
, "Received remote port open request for %s:%d",
5726 realpf
->dhost
, realpf
->dport
);
5729 sprintf(buf
, "Port open failed: %s", e
);
5731 error
= "Port open failed";
5733 logevent("Forwarded port opened successfully");
5734 c
->type
= CHAN_SOCKDATA
;
5737 } else if (typelen
== 22 &&
5738 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5739 if (!ssh
->agentfwd_enabled
)
5740 error
= "Agent forwarding is not enabled";
5742 c
->type
= CHAN_AGENT
; /* identify channel type */
5743 c
->u
.a
.lensofar
= 0;
5746 error
= "Unsupported channel type requested";
5749 c
->remoteid
= remid
;
5751 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5752 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5753 ssh2_pkt_adduint32(ssh
, SSH2_OPEN_CONNECT_FAILED
);
5754 ssh2_pkt_addstring(ssh
, error
);
5755 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5759 c
->localid
= alloc_channel_id(ssh
);
5761 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5762 c
->v
.v2
.remwindow
= winsize
;
5763 c
->v
.v2
.remmaxpkt
= pktsize
;
5764 bufchain_init(&c
->v
.v2
.outbuffer
);
5765 add234(ssh
->channels
, c
);
5766 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5767 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5768 ssh2_pkt_adduint32(ssh
, c
->localid
);
5769 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);
5770 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5774 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
5779 * We have spare data. Add it to the channel buffer.
5781 ssh2_add_channel_data(ssh
->mainchan
, in
, inlen
);
5786 struct ssh_channel
*c
;
5788 * Try to send data on all channels if we can.
5790 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
5791 int bufsize
= ssh2_try_send(c
);
5794 case CHAN_MAINSESSION
:
5795 /* stdin need not receive an unthrottle
5796 * notification since it will be polled */
5799 x11_unthrottle(c
->u
.x11
.s
);
5802 /* agent sockets are request/response and need no
5803 * buffer management */
5806 pfd_unthrottle(c
->u
.pfd
.s
);
5818 * Handle the top-level SSH2 protocol.
5820 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
5822 if (do_ssh2_transport(ssh
, in
, inlen
, ispkt
) == 0)
5824 do_ssh2_authconn(ssh
, in
, inlen
, ispkt
);
5828 * Called to set up the connection.
5830 * Returns an error message, or NULL on success.
5832 static char *ssh_init(void *frontend_handle
, void **backend_handle
,
5833 char *host
, int port
, char **realhost
, int nodelay
)
5838 ssh
= smalloc(sizeof(*ssh
));
5841 ssh
->v1_cipher_ctx
= NULL
;
5842 ssh
->crcda_ctx
= NULL
;
5843 ssh
->cscipher
= NULL
;
5844 ssh
->cs_cipher_ctx
= NULL
;
5845 ssh
->sccipher
= NULL
;
5846 ssh
->sc_cipher_ctx
= NULL
;
5848 ssh
->sc_mac_ctx
= NULL
;
5850 ssh
->sc_mac_ctx
= NULL
;
5852 ssh
->cs_comp_ctx
= NULL
;
5854 ssh
->sc_comp_ctx
= NULL
;
5856 ssh
->hostkey
= NULL
;
5858 ssh
->state
= SSH_STATE_PREPACKET
;
5859 ssh
->size_needed
= FALSE
;
5860 ssh
->eof_needed
= FALSE
;
5863 static const struct Packet empty
= { 0, 0, NULL
, NULL
, 0 };
5864 ssh
->pktin
= ssh
->pktout
= empty
;
5866 ssh
->deferred_send_data
= NULL
;
5867 ssh
->deferred_len
= 0;
5868 ssh
->deferred_size
= 0;
5869 ssh
->fallback_cmd
= 0;
5871 ssh
->v2_outgoing_sequence
= 0;
5872 ssh
->ssh1_rdpkt_crstate
= 0;
5873 ssh
->ssh2_rdpkt_crstate
= 0;
5874 ssh
->do_ssh_init_crstate
= 0;
5875 ssh
->ssh_gotdata_crstate
= 0;
5876 ssh
->ssh1_protocol_crstate
= 0;
5877 ssh
->do_ssh1_login_crstate
= 0;
5878 ssh
->do_ssh2_transport_crstate
= 0;
5879 ssh
->do_ssh2_authconn_crstate
= 0;
5880 ssh
->do_ssh_init_state
= NULL
;
5881 ssh
->do_ssh1_login_state
= NULL
;
5882 ssh
->do_ssh2_transport_state
= NULL
;
5883 ssh
->do_ssh2_authconn_state
= NULL
;
5885 *backend_handle
= ssh
;
5888 if (crypto_startup() == 0)
5889 return "Microsoft high encryption pack not installed!";
5892 ssh
->frontend
= frontend_handle
;
5893 ssh
->term_width
= cfg
.width
;
5894 ssh
->term_height
= cfg
.height
;
5899 ssh
->v1_throttle_count
= 0;
5900 ssh
->overall_bufsize
= 0;
5901 ssh
->fallback_cmd
= 0;
5903 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
);
5911 * Called to send data down the Telnet connection.
5913 static int ssh_send(void *handle
, char *buf
, int len
)
5915 Ssh ssh
= (Ssh
) handle
;
5917 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
5920 ssh
->protocol(ssh
, buf
, len
, 0);
5922 return ssh_sendbuffer(ssh
);
5926 * Called to query the current amount of buffered stdin data.
5928 static int ssh_sendbuffer(void *handle
)
5930 Ssh ssh
= (Ssh
) handle
;
5933 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
5937 * If the SSH socket itself has backed up, add the total backup
5938 * size on that to any individual buffer on the stdin channel.
5941 if (ssh
->throttled_all
)
5942 override_value
= ssh
->overall_bufsize
;
5944 if (ssh
->version
== 1) {
5945 return override_value
;
5946 } else if (ssh
->version
== 2) {
5947 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
5948 return override_value
;
5950 return (override_value
+
5951 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
5958 * Called to set the size of the window from SSH's POV.
5960 static void ssh_size(void *handle
, int width
, int height
)
5962 Ssh ssh
= (Ssh
) handle
;
5964 ssh
->term_width
= width
;
5965 ssh
->term_height
= height
;
5967 switch (ssh
->state
) {
5968 case SSH_STATE_BEFORE_SIZE
:
5969 case SSH_STATE_PREPACKET
:
5970 case SSH_STATE_CLOSED
:
5971 break; /* do nothing */
5972 case SSH_STATE_INTERMED
:
5973 ssh
->size_needed
= TRUE
; /* buffer for later */
5975 case SSH_STATE_SESSION
:
5979 if (ssh
->version
== 1) {
5980 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
5981 PKT_INT
, ssh
->term_height
,
5982 PKT_INT
, ssh
->term_width
,
5983 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5985 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5986 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5987 ssh2_pkt_addstring(ssh
, "window-change");
5988 ssh2_pkt_addbool(ssh
, 0);
5989 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5990 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5991 ssh2_pkt_adduint32(ssh
, 0);
5992 ssh2_pkt_adduint32(ssh
, 0);
6001 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6002 * can send an EOF and collect resulting output (e.g. `plink
6005 static void ssh_special(void *handle
, Telnet_Special code
)
6007 Ssh ssh
= (Ssh
) handle
;
6009 if (code
== TS_EOF
) {
6010 if (ssh
->state
!= SSH_STATE_SESSION
) {
6012 * Buffer the EOF in case we are pre-SESSION, so we can
6013 * send it as soon as we reach SESSION.
6016 ssh
->eof_needed
= TRUE
;
6019 if (ssh
->version
== 1) {
6020 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
6022 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_EOF
);
6023 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6026 logevent("Sent EOF message");
6027 } else if (code
== TS_PING
) {
6028 if (ssh
->state
== SSH_STATE_CLOSED
6029 || ssh
->state
== SSH_STATE_PREPACKET
) return;
6030 if (ssh
->version
== 1) {
6031 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
6032 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
6034 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
6035 ssh2_pkt_addstring_start(ssh
);
6043 void *new_sock_channel(void *handle
, Socket s
)
6045 Ssh ssh
= (Ssh
) handle
;
6046 struct ssh_channel
*c
;
6047 c
= smalloc(sizeof(struct ssh_channel
));
6051 c
->remoteid
= -1; /* to be set when open confirmed */
6052 c
->localid
= alloc_channel_id(ssh
);
6054 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
6056 bufchain_init(&c
->v
.v2
.outbuffer
);
6057 add234(ssh
->channels
, c
);
6063 * This is called when stdout/stderr (the entity to which
6064 * from_backend sends data) manages to clear some backlog.
6066 void ssh_unthrottle(void *handle
, int bufsize
)
6068 Ssh ssh
= (Ssh
) handle
;
6069 if (ssh
->version
== 1) {
6070 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
6071 ssh
->v1_stdout_throttling
= 0;
6072 ssh1_throttle(ssh
, -1);
6075 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
6076 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
6080 void ssh_send_port_open(void *handle
, void *channel
, char *hostname
,
6081 int port
, char *org
)
6083 Ssh ssh
= (Ssh
) handle
;
6084 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
6087 sprintf(buf
, "Opening forwarded connection to %.512s:%d", hostname
, port
);
6090 if (ssh
->version
== 1) {
6091 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
6092 PKT_INT
, c
->localid
,
6095 //PKT_STR, <org:orgport>,
6098 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
6099 ssh2_pkt_addstring(ssh
, "direct-tcpip");
6100 ssh2_pkt_adduint32(ssh
, c
->localid
);
6101 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6102 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);/* our window size */
6103 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
6104 ssh2_pkt_addstring(ssh
, hostname
);
6105 ssh2_pkt_adduint32(ssh
, port
);
6107 * We make up values for the originator data; partly it's
6108 * too much hassle to keep track, and partly I'm not
6109 * convinced the server should be told details like that
6110 * about my local network configuration.
6112 ssh2_pkt_addstring(ssh
, "client-side-connection");
6113 ssh2_pkt_adduint32(ssh
, 0);
6119 static Socket
ssh_socket(void *handle
)
6121 Ssh ssh
= (Ssh
) handle
;
6125 static int ssh_sendok(void *handle
)
6127 Ssh ssh
= (Ssh
) handle
;
6128 return ssh
->send_ok
;
6131 static int ssh_ldisc(void *handle
, int option
)
6133 Ssh ssh
= (Ssh
) handle
;
6134 if (option
== LD_ECHO
)
6135 return ssh
->echoing
;
6136 if (option
== LD_EDIT
)
6137 return ssh
->editing
;
6141 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
6143 Ssh ssh
= (Ssh
) handle
;
6147 static int ssh_return_exitcode(void *handle
)
6149 Ssh ssh
= (Ssh
) handle
;
6150 return ssh
->exitcode
;
6154 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6155 * that fails. This variable is the means by which scp.c can reach
6156 * into the SSH code and find out which one it got.
6158 extern int ssh_fallback_cmd(void *handle
)
6160 Ssh ssh
= (Ssh
) handle
;
6161 return ssh
->fallback_cmd
;
6164 Backend ssh_backend
= {
6171 ssh_return_exitcode
,