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
,
325 extern void pfd_close(Socket s
);
326 extern int pfd_send(Socket s
, char *data
, int len
);
327 extern void pfd_confirm(Socket s
);
328 extern void pfd_unthrottle(Socket s
);
329 extern void pfd_override_throttle(Socket s
, int enable
);
331 static void ssh2_pkt_init(Ssh
, int pkt_type
);
332 static void ssh2_pkt_addbool(Ssh
, unsigned char value
);
333 static void ssh2_pkt_adduint32(Ssh
, unsigned long value
);
334 static void ssh2_pkt_addstring_start(Ssh
);
335 static void ssh2_pkt_addstring_str(Ssh
, char *data
);
336 static void ssh2_pkt_addstring_data(Ssh
, char *data
, int len
);
337 static void ssh2_pkt_addstring(Ssh
, char *data
);
338 static char *ssh2_mpint_fmt(Bignum b
, int *len
);
339 static void ssh2_pkt_addmp(Ssh
, Bignum b
);
340 static int ssh2_pkt_construct(Ssh
);
341 static void ssh2_pkt_send(Ssh
);
344 * Buffer management constants. There are several of these for
345 * various different purposes:
347 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
348 * on a local data stream before we throttle the whole SSH
349 * connection (in SSH1 only). Throttling the whole connection is
350 * pretty drastic so we set this high in the hope it won't
353 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
354 * on the SSH connection itself before we defensively throttle
355 * _all_ local data streams. This is pretty drastic too (though
356 * thankfully unlikely in SSH2 since the window mechanism should
357 * ensure that the server never has any need to throttle its end
358 * of the connection), so we set this high as well.
360 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
364 #define SSH1_BUFFER_LIMIT 32768
365 #define SSH_MAX_BACKLOG 32768
366 #define OUR_V2_WINSIZE 16384
368 const static struct ssh_kex
*kex_algs
[] = {
369 &ssh_diffiehellman_gex
,
373 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
375 static void *nullmac_make_context(void)
379 static void nullmac_free_context(void *handle
)
382 static void nullmac_key(void *handle
, unsigned char *key
)
385 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
389 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
394 const static struct ssh_mac ssh_mac_none
= {
395 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
396 nullmac_generate
, nullmac_verify
, "none", 0
398 const static struct ssh_mac
*macs
[] = {
399 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
401 const static struct ssh_mac
*buggymacs
[] = {
402 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
405 static void *ssh_comp_none_init(void)
409 static void ssh_comp_none_cleanup(void *handle
)
412 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
413 unsigned char **outblock
, int *outlen
)
417 static int ssh_comp_none_disable(void *handle
)
421 const static struct ssh_compress ssh_comp_none
= {
423 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
424 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
425 ssh_comp_none_disable
, NULL
427 extern const struct ssh_compress ssh_zlib
;
428 const static struct ssh_compress
*compressions
[] = {
429 &ssh_zlib
, &ssh_comp_none
432 enum { /* channel types */
437 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
441 * 2-3-4 tree storing channels.
444 Ssh ssh
; /* pointer back to main context */
445 unsigned remoteid
, localid
;
448 * In SSH1, this value contains four bits:
450 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
451 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
452 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
453 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
455 * A channel is completely finished with when all four bits are set.
459 struct ssh1_data_channel
{
462 struct ssh2_data_channel
{
464 unsigned remwindow
, remmaxpkt
;
469 struct ssh_agent_channel
{
470 unsigned char *message
;
471 unsigned char msglen
[4];
472 int lensofar
, totallen
;
474 struct ssh_x11_channel
{
477 struct ssh_pfd_channel
{
484 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
485 * 2 use this structure in different ways, reflecting SSH 2's
486 * altogether saner approach to port forwarding.
488 * In SSH 1, you arrange a remote forwarding by sending the server
489 * the remote port number, and the local destination host:port.
490 * When a connection comes in, the server sends you back that
491 * host:port pair, and you connect to it. This is a ready-made
492 * security hole if you're not on the ball: a malicious server
493 * could send you back _any_ host:port pair, so if you trustingly
494 * connect to the address it gives you then you've just opened the
495 * entire inside of your corporate network just by connecting
496 * through it to a dodgy SSH server. Hence, we must store a list of
497 * host:port pairs we _are_ trying to forward to, and reject a
498 * connection request from the server if it's not in the list.
500 * In SSH 2, each side of the connection minds its own business and
501 * doesn't send unnecessary information to the other. You arrange a
502 * remote forwarding by sending the server just the remote port
503 * number. When a connection comes in, the server tells you which
504 * of its ports was connected to; and _you_ have to remember what
505 * local host:port pair went with that port number.
507 * Hence: in SSH 1 this structure stores host:port pairs we intend
508 * to allow connections to, and is indexed by those host:port
509 * pairs. In SSH 2 it stores a mapping from source port to
510 * destination host:port pair, and is indexed by source port.
512 struct ssh_rportfwd
{
513 unsigned sport
, dport
;
526 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
527 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
528 static void ssh_size(void *handle
, int width
, int height
);
529 static void ssh_special(void *handle
, Telnet_Special
);
530 static int ssh2_try_send(struct ssh_channel
*c
);
531 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
532 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
533 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
534 static int ssh_sendbuffer(void *handle
);
536 struct rdpkt1_state_tag
{
537 long len
, pad
, biglen
, to_read
;
538 unsigned long realcrc
, gotcrc
;
544 struct rdpkt2_state_tag
{
545 long len
, pad
, payload
, packetlen
, maclen
;
548 unsigned long incoming_sequence
;
552 const struct plug_function_table
*fn
;
553 /* the above field _must_ be first in the structure */
555 SHA_State exhash
, exhashbase
;
561 unsigned char session_key
[32];
563 int v1_remote_protoflags
;
564 int v1_local_protoflags
;
565 int agentfwd_enabled
;
568 const struct ssh_cipher
*cipher
;
571 const struct ssh2_cipher
*cscipher
, *sccipher
;
572 void *cs_cipher_ctx
, *sc_cipher_ctx
;
573 const struct ssh_mac
*csmac
, *scmac
;
574 void *cs_mac_ctx
, *sc_mac_ctx
;
575 const struct ssh_compress
*cscomp
, *sccomp
;
576 void *cs_comp_ctx
, *sc_comp_ctx
;
577 const struct ssh_kex
*kex
;
578 const struct ssh_signkey
*hostkey
;
579 unsigned char v2_session_id
[20];
585 int echoing
, editing
;
589 int term_width
, term_height
;
591 tree234
*channels
; /* indexed by local id */
592 struct ssh_channel
*mainchan
; /* primary session channel */
599 SSH_STATE_BEFORE_SIZE
,
605 int size_needed
, eof_needed
;
608 struct Packet pktout
;
609 unsigned char *deferred_send_data
;
610 int deferred_len
, deferred_size
;
613 * Gross hack: pscp will try to start SFTP but fall back to
614 * scp1 if that fails. This variable is the means by which
615 * scp.c can reach into the SSH code and find out which one it
621 * Used for username and password input.
623 char *userpass_input_buffer
;
624 int userpass_input_buflen
;
625 int userpass_input_bufpos
;
626 int userpass_input_echo
;
628 char *portfwd_strptr
;
632 int v1_throttle_count
;
635 int v1_stdout_throttling
;
636 int v2_outgoing_sequence
;
638 int ssh1_rdpkt_crstate
;
639 int ssh2_rdpkt_crstate
;
640 int do_ssh_init_crstate
;
641 int ssh_gotdata_crstate
;
642 int ssh1_protocol_crstate
;
643 int do_ssh1_login_crstate
;
644 int do_ssh2_transport_crstate
;
645 int do_ssh2_authconn_crstate
;
647 void *do_ssh_init_state
;
648 void *do_ssh1_login_state
;
649 void *do_ssh2_transport_state
;
650 void *do_ssh2_authconn_state
;
652 struct rdpkt1_state_tag rdpkt1_state
;
653 struct rdpkt2_state_tag rdpkt2_state
;
655 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
656 int (*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
659 static int ssh_channelcmp(void *av
, void *bv
)
661 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
662 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
663 if (a
->localid
< b
->localid
)
665 if (a
->localid
> b
->localid
)
669 static int ssh_channelfind(void *av
, void *bv
)
671 unsigned *a
= (unsigned *) av
;
672 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
680 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
682 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
683 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
685 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
686 return i
< 0 ?
-1 : +1;
687 if (a
->dport
> b
->dport
)
689 if (a
->dport
< b
->dport
)
694 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
696 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
697 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
699 if (a
->sport
> b
->sport
)
701 if (a
->sport
< b
->sport
)
706 static int alloc_channel_id(Ssh ssh
)
708 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
709 unsigned low
, high
, mid
;
711 struct ssh_channel
*c
;
714 * First-fit allocation of channel numbers: always pick the
715 * lowest unused one. To do this, binary-search using the
716 * counted B-tree to find the largest channel ID which is in a
717 * contiguous sequence from the beginning. (Precisely
718 * everything in that sequence must have ID equal to its tree
719 * index plus CHANNEL_NUMBER_OFFSET.)
721 tsize
= count234(ssh
->channels
);
725 while (high
- low
> 1) {
726 mid
= (high
+ low
) / 2;
727 c
= index234(ssh
->channels
, mid
);
728 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
729 low
= mid
; /* this one is fine */
731 high
= mid
; /* this one is past it */
734 * Now low points to either -1, or the tree index of the
735 * largest ID in the initial sequence.
738 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
739 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
741 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
744 static void c_write(Ssh ssh
, char *buf
, int len
)
746 if ((flags
& FLAG_STDERR
)) {
748 for (i
= 0; i
< len
; i
++)
750 fputc(buf
[i
], stderr
);
753 from_backend(ssh
->frontend
, 1, buf
, len
);
756 static void c_write_untrusted(Ssh ssh
, char *buf
, int len
)
759 for (i
= 0; i
< len
; i
++) {
761 c_write(ssh
, "\r\n", 2);
762 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
763 c_write(ssh
, buf
+ i
, 1);
767 static void c_write_str(Ssh ssh
, char *buf
)
769 c_write(ssh
, buf
, strlen(buf
));
773 * Collect incoming data in the incoming packet buffer.
774 * Decipher and verify the packet when it is completely read.
775 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
776 * Update the *data and *datalen variables.
777 * Return the additional nr of bytes needed, or 0 when
778 * a complete packet is available.
780 static int ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
782 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
784 crBegin(ssh
->ssh1_rdpkt_crstate
);
789 ssh
->pktin
.length
= 0;
791 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
792 while ((*datalen
) == 0)
794 st
->len
= (st
->len
<< 8) + **data
;
795 (*data
)++, (*datalen
)--;
798 st
->pad
= 8 - (st
->len
% 8);
799 st
->biglen
= st
->len
+ st
->pad
;
800 ssh
->pktin
.length
= st
->len
- 5;
802 if (ssh
->pktin
.maxlen
< st
->biglen
) {
803 ssh
->pktin
.maxlen
= st
->biglen
;
804 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
, st
->biglen
+ APIEXTRA
);
807 st
->to_read
= st
->biglen
;
808 st
->p
= ssh
->pktin
.data
;
809 while (st
->to_read
> 0) {
810 st
->chunk
= st
->to_read
;
811 while ((*datalen
) == 0)
812 crReturn(st
->to_read
);
813 if (st
->chunk
> (*datalen
))
814 st
->chunk
= (*datalen
);
815 memcpy(st
->p
, *data
, st
->chunk
);
817 *datalen
-= st
->chunk
;
819 st
->to_read
-= st
->chunk
;
822 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, ssh
->pktin
.data
,
824 bombout(("Network attack (CRC compensation) detected!"));
829 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, ssh
->pktin
.data
, st
->biglen
);
831 st
->realcrc
= crc32(ssh
->pktin
.data
, st
->biglen
- 4);
832 st
->gotcrc
= GET_32BIT(ssh
->pktin
.data
+ st
->biglen
- 4);
833 if (st
->gotcrc
!= st
->realcrc
) {
834 bombout(("Incorrect CRC received on packet"));
838 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
840 if (ssh
->v1_compressing
) {
841 unsigned char *decompblk
;
843 zlib_decompress_block(ssh
->sc_comp_ctx
,
844 ssh
->pktin
.body
- 1, ssh
->pktin
.length
+ 1,
845 &decompblk
, &decomplen
);
847 if (ssh
->pktin
.maxlen
< st
->pad
+ decomplen
) {
848 ssh
->pktin
.maxlen
= st
->pad
+ decomplen
;
849 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
850 ssh
->pktin
.maxlen
+ APIEXTRA
);
851 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
854 memcpy(ssh
->pktin
.body
- 1, decompblk
, decomplen
);
856 ssh
->pktin
.length
= decomplen
- 1;
859 ssh
->pktin
.type
= ssh
->pktin
.body
[-1];
861 log_packet(PKT_INCOMING
, ssh
->pktin
.type
, ssh1_pkt_type(ssh
->pktin
.type
),
862 ssh
->pktin
.body
, ssh
->pktin
.length
);
864 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
865 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
||
866 ssh
->pktin
.type
== SSH1_MSG_DEBUG
||
867 ssh
->pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
868 ssh
->pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
869 long stringlen
= GET_32BIT(ssh
->pktin
.body
);
870 if (stringlen
+ 4 != ssh
->pktin
.length
) {
871 bombout(("Received data packet with bogus string length"));
876 if (ssh
->pktin
.type
== SSH1_MSG_DEBUG
) {
877 /* log debug message */
879 int stringlen
= GET_32BIT(ssh
->pktin
.body
);
880 strcpy(buf
, "Remote debug message: ");
883 memcpy(buf
+ 8, ssh
->pktin
.body
+ 4, stringlen
);
884 buf
[8 + stringlen
] = '\0';
887 } else if (ssh
->pktin
.type
== SSH1_MSG_IGNORE
) {
892 if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
893 /* log reason code in disconnect message */
895 unsigned msglen
= GET_32BIT(ssh
->pktin
.body
);
897 strcpy(buf
, "Remote sent disconnect: ");
898 nowlen
= strlen(buf
);
899 if (msglen
> sizeof(buf
) - nowlen
- 1)
900 msglen
= sizeof(buf
) - nowlen
- 1;
901 memcpy(buf
+ nowlen
, ssh
->pktin
.body
+ 4, msglen
);
902 buf
[nowlen
+ msglen
] = '\0';
903 /* logevent(buf); (this is now done within the bombout macro) */
904 bombout(("Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
911 static int ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
913 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
915 crBegin(ssh
->ssh2_rdpkt_crstate
);
919 ssh
->pktin
.length
= 0;
921 st
->cipherblk
= ssh
->sccipher
->blksize
;
924 if (st
->cipherblk
< 8)
927 if (ssh
->pktin
.maxlen
< st
->cipherblk
) {
928 ssh
->pktin
.maxlen
= st
->cipherblk
;
929 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
, st
->cipherblk
+ APIEXTRA
);
933 * Acquire and decrypt the first block of the packet. This will
934 * contain the length and padding details.
936 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
937 while ((*datalen
) == 0)
938 crReturn(st
->cipherblk
- st
->i
);
939 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
944 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
945 ssh
->pktin
.data
, st
->cipherblk
);
948 * Now get the length and padding figures.
950 st
->len
= GET_32BIT(ssh
->pktin
.data
);
951 st
->pad
= ssh
->pktin
.data
[4];
954 * _Completely_ silly lengths should be stomped on before they
955 * do us any more damage.
957 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
958 bombout(("Incoming packet was garbled on decryption"));
963 * This enables us to deduce the payload length.
965 st
->payload
= st
->len
- st
->pad
- 1;
967 ssh
->pktin
.length
= st
->payload
+ 5;
970 * So now we can work out the total packet length.
972 st
->packetlen
= st
->len
+ 4;
973 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
976 * Adjust memory allocation if packet is too big.
978 if (ssh
->pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
979 ssh
->pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
980 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
981 ssh
->pktin
.maxlen
+ APIEXTRA
);
985 * Read and decrypt the remainder of the packet.
987 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
989 while ((*datalen
) == 0)
990 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
991 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
994 /* Decrypt everything _except_ the MAC. */
996 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
997 ssh
->pktin
.data
+ st
->cipherblk
,
998 st
->packetlen
- st
->cipherblk
);
1004 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, ssh
->pktin
.data
, st
->len
+ 4,
1005 st
->incoming_sequence
)) {
1006 bombout(("Incorrect MAC received on packet"));
1009 st
->incoming_sequence
++; /* whether or not we MACed */
1012 * Decompress packet payload.
1015 unsigned char *newpayload
;
1018 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1019 ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5,
1020 &newpayload
, &newlen
)) {
1021 if (ssh
->pktin
.maxlen
< newlen
+ 5) {
1022 ssh
->pktin
.maxlen
= newlen
+ 5;
1023 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
1024 ssh
->pktin
.maxlen
+ APIEXTRA
);
1026 ssh
->pktin
.length
= 5 + newlen
;
1027 memcpy(ssh
->pktin
.data
+ 5, newpayload
, newlen
);
1032 ssh
->pktin
.savedpos
= 6;
1033 ssh
->pktin
.type
= ssh
->pktin
.data
[5];
1035 log_packet(PKT_INCOMING
, ssh
->pktin
.type
,
1036 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktin
.type
),
1037 ssh
->pktin
.data
+6, ssh
->pktin
.length
-6);
1039 switch (ssh
->pktin
.type
) {
1041 * These packets we must handle instantly.
1043 case SSH2_MSG_DISCONNECT
:
1045 /* log reason code in disconnect message */
1047 int reason
= GET_32BIT(ssh
->pktin
.data
+ 6);
1048 unsigned msglen
= GET_32BIT(ssh
->pktin
.data
+ 10);
1050 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1051 sprintf(buf
, "Received disconnect message (%s)",
1052 ssh2_disconnect_reasons
[reason
]);
1054 sprintf(buf
, "Received disconnect message (unknown type %d)",
1058 strcpy(buf
, "Disconnection message text: ");
1059 nowlen
= strlen(buf
);
1060 if (msglen
> sizeof(buf
) - nowlen
- 1)
1061 msglen
= sizeof(buf
) - nowlen
- 1;
1062 memcpy(buf
+ nowlen
, ssh
->pktin
.data
+ 14, msglen
);
1063 buf
[nowlen
+ msglen
] = '\0';
1065 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1067 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1068 ssh2_disconnect_reasons
[reason
] : "unknown",
1073 case SSH2_MSG_IGNORE
:
1075 case SSH2_MSG_DEBUG
:
1077 /* log the debug message */
1079 /* int display = ssh->pktin.body[6]; */
1080 int stringlen
= GET_32BIT(ssh
->pktin
.data
+7);
1082 strcpy(buf
, "Remote debug message: ");
1083 prefix
= strlen(buf
);
1084 if (stringlen
> (int)(sizeof(buf
)-prefix
-1))
1085 stringlen
= sizeof(buf
)-prefix
-1;
1086 memcpy(buf
+ prefix
, ssh
->pktin
.data
+ 11, stringlen
);
1087 buf
[prefix
+ stringlen
] = '\0';
1090 goto next_packet
; /* FIXME: print the debug message */
1093 * These packets we need do nothing about here.
1095 case SSH2_MSG_UNIMPLEMENTED
:
1096 case SSH2_MSG_SERVICE_REQUEST
:
1097 case SSH2_MSG_SERVICE_ACCEPT
:
1098 case SSH2_MSG_KEXINIT
:
1099 case SSH2_MSG_NEWKEYS
:
1100 case SSH2_MSG_KEXDH_INIT
:
1101 case SSH2_MSG_KEXDH_REPLY
:
1102 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1103 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1104 case SSH2_MSG_KEX_DH_GEX_INIT
:
1105 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1106 case SSH2_MSG_USERAUTH_REQUEST
:
1107 case SSH2_MSG_USERAUTH_FAILURE
:
1108 case SSH2_MSG_USERAUTH_SUCCESS
:
1109 case SSH2_MSG_USERAUTH_BANNER
:
1110 case SSH2_MSG_USERAUTH_PK_OK
:
1111 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1112 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1113 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1114 case SSH2_MSG_GLOBAL_REQUEST
:
1115 case SSH2_MSG_REQUEST_SUCCESS
:
1116 case SSH2_MSG_REQUEST_FAILURE
:
1117 case SSH2_MSG_CHANNEL_OPEN
:
1118 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1119 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1120 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1121 case SSH2_MSG_CHANNEL_DATA
:
1122 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1123 case SSH2_MSG_CHANNEL_EOF
:
1124 case SSH2_MSG_CHANNEL_CLOSE
:
1125 case SSH2_MSG_CHANNEL_REQUEST
:
1126 case SSH2_MSG_CHANNEL_SUCCESS
:
1127 case SSH2_MSG_CHANNEL_FAILURE
:
1131 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1134 ssh2_pkt_init(ssh
, SSH2_MSG_UNIMPLEMENTED
);
1135 ssh2_pkt_adduint32(ssh
, st
->incoming_sequence
- 1);
1143 static void ssh1_pktout_size(Ssh ssh
, int len
)
1147 len
+= 5; /* type and CRC */
1148 pad
= 8 - (len
% 8);
1151 ssh
->pktout
.length
= len
- 5;
1152 if (ssh
->pktout
.maxlen
< biglen
) {
1153 ssh
->pktout
.maxlen
= biglen
;
1155 /* Allocate enough buffer space for extra block
1156 * for MS CryptEncrypt() */
1157 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
, biglen
+ 12);
1159 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
, biglen
+ 4);
1162 ssh
->pktout
.body
= ssh
->pktout
.data
+ 4 + pad
+ 1;
1165 static void s_wrpkt_start(Ssh ssh
, int type
, int len
)
1167 ssh1_pktout_size(ssh
, len
);
1168 ssh
->pktout
.type
= type
;
1171 static int s_wrpkt_prepare(Ssh ssh
)
1173 int pad
, len
, biglen
, i
;
1176 ssh
->pktout
.body
[-1] = ssh
->pktout
.type
;
1178 log_packet(PKT_OUTGOING
, ssh
->pktout
.type
, ssh1_pkt_type(ssh
->pktout
.type
),
1179 ssh
->pktout
.body
, ssh
->pktout
.length
);
1181 if (ssh
->v1_compressing
) {
1182 unsigned char *compblk
;
1184 zlib_compress_block(ssh
->cs_comp_ctx
,
1185 ssh
->pktout
.body
- 1, ssh
->pktout
.length
+ 1,
1186 &compblk
, &complen
);
1187 ssh1_pktout_size(ssh
, complen
- 1);
1188 memcpy(ssh
->pktout
.body
- 1, compblk
, complen
);
1192 len
= ssh
->pktout
.length
+ 5; /* type and CRC */
1193 pad
= 8 - (len
% 8);
1196 for (i
= 0; i
< pad
; i
++)
1197 ssh
->pktout
.data
[i
+ 4] = random_byte();
1198 crc
= crc32(ssh
->pktout
.data
+ 4, biglen
- 4);
1199 PUT_32BIT(ssh
->pktout
.data
+ biglen
, crc
);
1200 PUT_32BIT(ssh
->pktout
.data
, len
);
1203 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, ssh
->pktout
.data
+ 4, biglen
);
1208 static void s_wrpkt(Ssh ssh
)
1211 len
= s_wrpkt_prepare(ssh
);
1212 backlog
= sk_write(ssh
->s
, ssh
->pktout
.data
, len
);
1213 if (backlog
> SSH_MAX_BACKLOG
)
1214 ssh_throttle_all(ssh
, 1, backlog
);
1217 static void s_wrpkt_defer(Ssh ssh
)
1220 len
= s_wrpkt_prepare(ssh
);
1221 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1222 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1223 ssh
->deferred_send_data
= srealloc(ssh
->deferred_send_data
,
1224 ssh
->deferred_size
);
1226 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1227 ssh
->deferred_len
+= len
;
1231 * Construct a packet with the specified contents.
1233 static void construct_packet(Ssh ssh
, int pkttype
, va_list ap1
, va_list ap2
)
1235 unsigned char *p
, *argp
, argchar
;
1236 unsigned long argint
;
1237 int pktlen
, argtype
, arglen
;
1241 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1244 (void) va_arg(ap1
, int);
1248 (void) va_arg(ap1
, char);
1252 (void) va_arg(ap1
, unsigned char *);
1253 arglen
= va_arg(ap1
, int);
1257 argp
= va_arg(ap1
, unsigned char *);
1258 arglen
= strlen(argp
);
1259 pktlen
+= 4 + arglen
;
1262 bn
= va_arg(ap1
, Bignum
);
1263 pktlen
+= ssh1_bignum_length(bn
);
1270 s_wrpkt_start(ssh
, pkttype
, pktlen
);
1271 p
= ssh
->pktout
.body
;
1273 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1276 argint
= va_arg(ap2
, int);
1277 PUT_32BIT(p
, argint
);
1281 argchar
= va_arg(ap2
, unsigned char);
1286 argp
= va_arg(ap2
, unsigned char *);
1287 arglen
= va_arg(ap2
, int);
1288 memcpy(p
, argp
, arglen
);
1292 argp
= va_arg(ap2
, unsigned char *);
1293 arglen
= strlen(argp
);
1294 PUT_32BIT(p
, arglen
);
1295 memcpy(p
+ 4, argp
, arglen
);
1299 bn
= va_arg(ap2
, Bignum
);
1300 p
+= ssh1_write_bignum(p
, bn
);
1306 static void send_packet(Ssh ssh
, int pkttype
, ...)
1309 va_start(ap1
, pkttype
);
1310 va_start(ap2
, pkttype
);
1311 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1315 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1318 va_start(ap1
, pkttype
);
1319 va_start(ap2
, pkttype
);
1320 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1324 static int ssh_versioncmp(char *a
, char *b
)
1327 unsigned long av
, bv
;
1329 av
= strtoul(a
, &ae
, 10);
1330 bv
= strtoul(b
, &be
, 10);
1332 return (av
< bv ?
-1 : +1);
1337 av
= strtoul(ae
, &ae
, 10);
1338 bv
= strtoul(be
, &be
, 10);
1340 return (av
< bv ?
-1 : +1);
1345 * Utility routines for putting an SSH-protocol `string' and
1346 * `uint32' into a SHA state.
1349 static void sha_string(SHA_State
* s
, void *str
, int len
)
1351 unsigned char lenblk
[4];
1352 PUT_32BIT(lenblk
, len
);
1353 SHA_Bytes(s
, lenblk
, 4);
1354 SHA_Bytes(s
, str
, len
);
1357 static void sha_uint32(SHA_State
* s
, unsigned i
)
1359 unsigned char intblk
[4];
1360 PUT_32BIT(intblk
, i
);
1361 SHA_Bytes(s
, intblk
, 4);
1365 * SSH2 packet construction functions.
1367 static void ssh2_pkt_ensure(Ssh ssh
, int length
)
1369 if (ssh
->pktout
.maxlen
< length
) {
1370 ssh
->pktout
.maxlen
= length
+ 256;
1371 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
,
1372 ssh
->pktout
.maxlen
+ APIEXTRA
);
1373 if (!ssh
->pktout
.data
)
1374 fatalbox("Out of memory");
1377 static void ssh2_pkt_adddata(Ssh ssh
, void *data
, int len
)
1379 ssh
->pktout
.length
+= len
;
1380 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
);
1381 memcpy(ssh
->pktout
.data
+ ssh
->pktout
.length
- len
, data
, len
);
1383 static void ssh2_pkt_addbyte(Ssh ssh
, unsigned char byte
)
1385 ssh2_pkt_adddata(ssh
, &byte
, 1);
1387 static void ssh2_pkt_init(Ssh ssh
, int pkt_type
)
1389 ssh
->pktout
.length
= 5;
1390 ssh2_pkt_addbyte(ssh
, (unsigned char) pkt_type
);
1392 static void ssh2_pkt_addbool(Ssh ssh
, unsigned char value
)
1394 ssh2_pkt_adddata(ssh
, &value
, 1);
1396 static void ssh2_pkt_adduint32(Ssh ssh
, unsigned long value
)
1399 PUT_32BIT(x
, value
);
1400 ssh2_pkt_adddata(ssh
, x
, 4);
1402 static void ssh2_pkt_addstring_start(Ssh ssh
)
1404 ssh2_pkt_adduint32(ssh
, 0);
1405 ssh
->pktout
.savedpos
= ssh
->pktout
.length
;
1407 static void ssh2_pkt_addstring_str(Ssh ssh
, char *data
)
1409 ssh2_pkt_adddata(ssh
, data
, strlen(data
));
1410 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1411 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1413 static void ssh2_pkt_addstring_data(Ssh ssh
, char *data
, int len
)
1415 ssh2_pkt_adddata(ssh
, data
, len
);
1416 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1417 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1419 static void ssh2_pkt_addstring(Ssh ssh
, char *data
)
1421 ssh2_pkt_addstring_start(ssh
);
1422 ssh2_pkt_addstring_str(ssh
, data
);
1424 static char *ssh2_mpint_fmt(Bignum b
, int *len
)
1427 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1430 fatalbox("out of memory");
1432 for (i
= 1; i
<= n
; i
++)
1433 p
[i
] = bignum_byte(b
, n
- i
);
1435 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1437 memmove(p
, p
+ i
, n
+ 1 - i
);
1441 static void ssh2_pkt_addmp(Ssh ssh
, Bignum b
)
1445 p
= ssh2_mpint_fmt(b
, &len
);
1446 ssh2_pkt_addstring_start(ssh
);
1447 ssh2_pkt_addstring_data(ssh
, p
, len
);
1452 * Construct an SSH2 final-form packet: compress it, encrypt it,
1453 * put the MAC on it. Final packet, ready to be sent, is stored in
1454 * ssh->pktout.data. Total length is returned.
1456 static int ssh2_pkt_construct(Ssh ssh
)
1458 int cipherblk
, maclen
, padding
, i
;
1460 log_packet(PKT_OUTGOING
, ssh
->pktout
.data
[5],
1461 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktout
.data
[5]),
1462 ssh
->pktout
.data
+ 6, ssh
->pktout
.length
- 6);
1465 * Compress packet payload.
1468 unsigned char *newpayload
;
1471 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, ssh
->pktout
.data
+ 5,
1472 ssh
->pktout
.length
- 5,
1473 &newpayload
, &newlen
)) {
1474 ssh
->pktout
.length
= 5;
1475 ssh2_pkt_adddata(ssh
, newpayload
, newlen
);
1481 * Add padding. At least four bytes, and must also bring total
1482 * length (minus MAC) up to a multiple of the block size.
1484 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1485 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1488 (cipherblk
- (ssh
->pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1489 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1490 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
+ padding
+ maclen
);
1491 ssh
->pktout
.data
[4] = padding
;
1492 for (i
= 0; i
< padding
; i
++)
1493 ssh
->pktout
.data
[ssh
->pktout
.length
+ i
] = random_byte();
1494 PUT_32BIT(ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
- 4);
1496 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, ssh
->pktout
.data
,
1497 ssh
->pktout
.length
+ padding
,
1498 ssh
->v2_outgoing_sequence
);
1499 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1502 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1503 ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
);
1505 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1506 return ssh
->pktout
.length
+ padding
+ maclen
;
1510 * Construct and send an SSH2 packet immediately.
1512 static void ssh2_pkt_send(Ssh ssh
)
1516 len
= ssh2_pkt_construct(ssh
);
1517 backlog
= sk_write(ssh
->s
, ssh
->pktout
.data
, len
);
1518 if (backlog
> SSH_MAX_BACKLOG
)
1519 ssh_throttle_all(ssh
, 1, backlog
);
1523 * Construct an SSH2 packet and add it to a deferred data block.
1524 * Useful for sending multiple packets in a single sk_write() call,
1525 * to prevent a traffic-analysing listener from being able to work
1526 * out the length of any particular packet (such as the password
1529 * Note that because SSH2 sequence-numbers its packets, this can
1530 * NOT be used as an m4-style `defer' allowing packets to be
1531 * constructed in one order and sent in another.
1533 static void ssh2_pkt_defer(Ssh ssh
)
1535 int len
= ssh2_pkt_construct(ssh
);
1536 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1537 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1538 ssh
->deferred_send_data
= srealloc(ssh
->deferred_send_data
,
1539 ssh
->deferred_size
);
1541 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1542 ssh
->deferred_len
+= len
;
1546 * Send the whole deferred data block constructed by
1547 * ssh2_pkt_defer() or SSH1's defer_packet().
1549 static void ssh_pkt_defersend(Ssh ssh
)
1552 backlog
= sk_write(ssh
->s
, ssh
->deferred_send_data
, ssh
->deferred_len
);
1553 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1554 sfree(ssh
->deferred_send_data
);
1555 ssh
->deferred_send_data
= NULL
;
1556 if (backlog
> SSH_MAX_BACKLOG
)
1557 ssh_throttle_all(ssh
, 1, backlog
);
1561 void bndebug(char *string
, Bignum b
)
1565 p
= ssh2_mpint_fmt(b
, &len
);
1566 debug(("%s", string
));
1567 for (i
= 0; i
< len
; i
++)
1568 debug((" %02x", p
[i
]));
1574 static void sha_mpint(SHA_State
* s
, Bignum b
)
1578 p
= ssh2_mpint_fmt(b
, &len
);
1579 sha_string(s
, p
, len
);
1584 * SSH2 packet decode functions.
1586 static unsigned long ssh2_pkt_getuint32(Ssh ssh
)
1588 unsigned long value
;
1589 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1590 return 0; /* arrgh, no way to decline (FIXME?) */
1591 value
= GET_32BIT(ssh
->pktin
.data
+ ssh
->pktin
.savedpos
);
1592 ssh
->pktin
.savedpos
+= 4;
1595 static int ssh2_pkt_getbool(Ssh ssh
)
1597 unsigned long value
;
1598 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 1)
1599 return 0; /* arrgh, no way to decline (FIXME?) */
1600 value
= ssh
->pktin
.data
[ssh
->pktin
.savedpos
] != 0;
1601 ssh
->pktin
.savedpos
++;
1604 static void ssh2_pkt_getstring(Ssh ssh
, char **p
, int *length
)
1608 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1610 *length
= GET_32BIT(ssh
->pktin
.data
+ ssh
->pktin
.savedpos
);
1611 ssh
->pktin
.savedpos
+= 4;
1612 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< *length
)
1614 *p
= ssh
->pktin
.data
+ ssh
->pktin
.savedpos
;
1615 ssh
->pktin
.savedpos
+= *length
;
1617 static Bignum
ssh2_pkt_getmp(Ssh ssh
)
1623 ssh2_pkt_getstring(ssh
, &p
, &length
);
1627 bombout(("internal error: Can't handle negative mpints"));
1630 b
= bignum_from_bytes(p
, length
);
1635 * Helper function to add an SSH2 signature blob to a packet.
1636 * Expects to be shown the public key blob as well as the signature
1637 * blob. Normally works just like ssh2_pkt_addstring, but will
1638 * fiddle with the signature packet if necessary for
1639 * BUG_SSH2_RSA_PADDING.
1641 static void ssh2_add_sigblob(Ssh ssh
, void *pkblob_v
, int pkblob_len
,
1642 void *sigblob_v
, int sigblob_len
)
1644 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1645 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1647 /* dmemdump(pkblob, pkblob_len); */
1648 /* dmemdump(sigblob, sigblob_len); */
1651 * See if this is in fact an ssh-rsa signature and a buggy
1652 * server; otherwise we can just do this the easy way.
1654 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1655 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1656 int pos
, len
, siglen
;
1659 * Find the byte length of the modulus.
1662 pos
= 4+7; /* skip over "ssh-rsa" */
1663 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1664 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1665 pos
+= 4; /* find modulus itself */
1666 while (len
> 0 && pkblob
[pos
] == 0)
1668 /* debug(("modulus length is %d\n", len)); */
1671 * Now find the signature integer.
1673 pos
= 4+7; /* skip over "ssh-rsa" */
1674 siglen
= GET_32BIT(sigblob
+pos
);
1675 /* debug(("signature length is %d\n", siglen)); */
1677 if (len
!= siglen
) {
1678 unsigned char newlen
[4];
1679 ssh2_pkt_addstring_start(ssh
);
1680 ssh2_pkt_addstring_data(ssh
, sigblob
, pos
);
1681 /* dmemdump(sigblob, pos); */
1682 pos
+= 4; /* point to start of actual sig */
1683 PUT_32BIT(newlen
, len
);
1684 ssh2_pkt_addstring_data(ssh
, newlen
, 4);
1685 /* dmemdump(newlen, 4); */
1687 while (len
-- > siglen
) {
1688 ssh2_pkt_addstring_data(ssh
, newlen
, 1);
1689 /* dmemdump(newlen, 1); */
1691 ssh2_pkt_addstring_data(ssh
, sigblob
+pos
, siglen
);
1692 /* dmemdump(sigblob+pos, siglen); */
1696 /* Otherwise fall through and do it the easy way. */
1699 ssh2_pkt_addstring_start(ssh
);
1700 ssh2_pkt_addstring_data(ssh
, sigblob
, sigblob_len
);
1704 * Examine the remote side's version string and compare it against
1705 * a list of known buggy implementations.
1707 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1709 char *imp
; /* pointer to implementation part */
1711 imp
+= strcspn(imp
, "-");
1713 imp
+= strcspn(imp
, "-");
1716 ssh
->remote_bugs
= 0;
1718 if (cfg
.sshbug_ignore1
== BUG_ON
||
1719 (cfg
.sshbug_ignore1
== BUG_AUTO
&&
1720 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1721 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1722 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")))) {
1724 * These versions don't support SSH1_MSG_IGNORE, so we have
1725 * to use a different defence against password length
1728 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1729 logevent("We believe remote version has SSH1 ignore bug");
1732 if (cfg
.sshbug_plainpw1
== BUG_ON
||
1733 (cfg
.sshbug_plainpw1
== BUG_AUTO
&&
1734 (!strcmp(imp
, "Cisco-1.25")))) {
1736 * These versions need a plain password sent; they can't
1737 * handle having a null and a random length of data after
1740 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1741 logevent("We believe remote version needs a plain SSH1 password");
1744 if (cfg
.sshbug_rsa1
== BUG_ON
||
1745 (cfg
.sshbug_rsa1
== BUG_AUTO
&&
1746 (!strcmp(imp
, "Cisco-1.25")))) {
1748 * These versions apparently have no clue whatever about
1749 * RSA authentication and will panic and die if they see
1750 * an AUTH_RSA message.
1752 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
1753 logevent("We believe remote version can't handle RSA authentication");
1756 if (cfg
.sshbug_hmac2
== BUG_ON
||
1757 (cfg
.sshbug_hmac2
== BUG_AUTO
&&
1758 (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1759 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1760 !strncmp(imp
, "2.1 ", 4)))) {
1762 * These versions have the HMAC bug.
1764 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
1765 logevent("We believe remote version has SSH2 HMAC bug");
1768 if (cfg
.sshbug_derivekey2
== BUG_ON
||
1769 (cfg
.sshbug_derivekey2
== BUG_AUTO
&&
1770 (!strncmp(imp
, "2.0.", 4)))) {
1772 * These versions have the key-derivation bug (failing to
1773 * include the literal shared secret in the hashes that
1774 * generate the keys).
1776 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1777 logevent("We believe remote version has SSH2 key-derivation bug");
1780 if (cfg
.sshbug_rsapad2
== BUG_ON
||
1781 (cfg
.sshbug_rsapad2
== BUG_AUTO
&&
1782 ((!strncmp(imp
, "OpenSSH_2.", 10) && imp
[10]>='5' && imp
[10]<='9') ||
1783 (!strncmp(imp
, "OpenSSH_3.", 10) && imp
[10]>='0' && imp
[10]<='2')))){
1785 * These versions have the SSH2 RSA padding bug.
1787 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1788 logevent("We believe remote version has SSH2 RSA padding bug");
1791 if (cfg
.sshbug_dhgex2
== BUG_ON
) {
1793 * These versions have the SSH2 DH GEX bug.
1795 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
1796 logevent("We believe remote version has SSH2 DH group exchange bug");
1800 static int do_ssh_init(Ssh ssh
, unsigned char c
)
1802 struct do_ssh_init_state
{
1810 crState(do_ssh_init_state
);
1812 crBegin(ssh
->do_ssh_init_crstate
);
1814 /* Search for the string "SSH-" in the input. */
1817 static const int transS
[] = { 1, 2, 2, 1 };
1818 static const int transH
[] = { 0, 0, 3, 0 };
1819 static const int transminus
[] = { 0, 0, 0, -1 };
1821 s
->i
= transS
[s
->i
];
1823 s
->i
= transH
[s
->i
];
1825 s
->i
= transminus
[s
->i
];
1830 crReturn(1); /* get another character */
1834 s
->vstring
= smalloc(s
->vstrsize
);
1835 strcpy(s
->vstring
, "SSH-");
1839 crReturn(1); /* get another char */
1840 if (s
->vslen
>= s
->vstrsize
- 1) {
1842 s
->vstring
= srealloc(s
->vstring
, s
->vstrsize
);
1844 s
->vstring
[s
->vslen
++] = c
;
1847 s
->version
[s
->i
] = '\0';
1849 } else if (s
->i
< sizeof(s
->version
) - 1)
1850 s
->version
[s
->i
++] = c
;
1851 } else if (c
== '\n')
1855 ssh
->agentfwd_enabled
= FALSE
;
1856 ssh
->rdpkt2_state
.incoming_sequence
= 0;
1858 s
->vstring
[s
->vslen
] = 0;
1859 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
1862 vlog
= smalloc(20 + s
->vslen
);
1863 sprintf(vlog
, "Server version: %s", s
->vstring
);
1867 ssh_detect_bugs(ssh
, s
->vstring
);
1870 * Decide which SSH protocol version to support.
1873 /* Anything strictly below "2.0" means protocol 1 is supported. */
1874 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
1875 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1876 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
1878 if (cfg
.sshprot
== 0 && !s
->proto1
) {
1879 bombout(("SSH protocol version 1 required by user but not provided by server"));
1882 if (cfg
.sshprot
== 3 && !s
->proto2
) {
1883 bombout(("SSH protocol version 2 required by user but not provided by server"));
1887 if (s
->proto2
&& (cfg
.sshprot
>= 2 || !s
->proto1
)) {
1891 char verstring
[80], vlog
[100];
1892 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1893 SHA_Init(&ssh
->exhashbase
);
1895 * Hash our version string and their version string.
1897 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
1898 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
1899 sprintf(vlog
, "We claim version: %s", verstring
);
1901 strcat(verstring
, "\n");
1902 logevent("Using SSH protocol version 2");
1903 sk_write(ssh
->s
, verstring
, strlen(verstring
));
1904 ssh
->protocol
= ssh2_protocol
;
1906 ssh
->s_rdpkt
= ssh2_rdpkt
;
1911 char verstring
[80], vlog
[100];
1912 sprintf(verstring
, "SSH-%s-%s",
1913 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
1915 sprintf(vlog
, "We claim version: %s", verstring
);
1917 strcat(verstring
, "\n");
1919 logevent("Using SSH protocol version 1");
1920 sk_write(ssh
->s
, verstring
, strlen(verstring
));
1921 ssh
->protocol
= ssh1_protocol
;
1923 ssh
->s_rdpkt
= ssh1_rdpkt
;
1925 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
1932 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
1934 crBegin(ssh
->ssh_gotdata_crstate
);
1937 * To begin with, feed the characters one by one to the
1938 * protocol initialisation / selection function do_ssh_init().
1939 * When that returns 0, we're done with the initial greeting
1940 * exchange and can move on to packet discipline.
1943 int ret
; /* need not be kept across crReturn */
1945 crReturnV
; /* more data please */
1946 ret
= do_ssh_init(ssh
, *data
);
1954 * We emerge from that loop when the initial negotiation is
1955 * over and we have selected an s_rdpkt function. Now pass
1956 * everything to s_rdpkt, and then pass the resulting packets
1957 * to the proper protocol handler.
1962 while (datalen
> 0) {
1963 if (ssh
->s_rdpkt(ssh
, &data
, &datalen
) == 0) {
1964 if (ssh
->state
== SSH_STATE_CLOSED
) {
1967 ssh
->protocol(ssh
, NULL
, 0, 1);
1968 if (ssh
->state
== SSH_STATE_CLOSED
) {
1978 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
1981 Ssh ssh
= (Ssh
) plug
;
1982 ssh
->state
= SSH_STATE_CLOSED
;
1988 /* A socket error has occurred. */
1989 logevent(error_msg
);
1990 connection_fatal(error_msg
);
1992 /* Otherwise, the remote side closed the connection normally. */
1997 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
1999 Ssh ssh
= (Ssh
) plug
;
2000 ssh_gotdata(ssh
, data
, len
);
2001 if (ssh
->state
== SSH_STATE_CLOSED
) {
2011 static void ssh_sent(Plug plug
, int bufsize
)
2013 Ssh ssh
= (Ssh
) plug
;
2015 * If the send backlog on the SSH socket itself clears, we
2016 * should unthrottle the whole world if it was throttled.
2018 if (bufsize
< SSH_MAX_BACKLOG
)
2019 ssh_throttle_all(ssh
, 0, bufsize
);
2023 * Connect to specified host and port.
2024 * Returns an error message, or NULL on success.
2025 * Also places the canonical host name into `realhost'. It must be
2026 * freed by the caller.
2028 static char *connect_to_host(Ssh ssh
, char *host
, int port
,
2029 char **realhost
, int nodelay
)
2031 static const struct plug_function_table fn_table
= {
2041 ssh
->savedhost
= smalloc(1 + strlen(host
));
2042 if (!ssh
->savedhost
)
2043 fatalbox("Out of memory");
2044 strcpy(ssh
->savedhost
, host
);
2047 port
= 22; /* default ssh port */
2048 ssh
->savedport
= port
;
2055 sprintf(buf
, "Looking up host \"%.170s\"", host
);
2058 addr
= sk_namelookup(host
, realhost
);
2059 if ((err
= sk_addr_error(addr
)))
2066 char buf
[200], addrbuf
[100];
2067 sk_getaddr(addr
, addrbuf
, 100);
2068 sprintf(buf
, "Connecting to %.100s port %d", addrbuf
, port
);
2071 ssh
->fn
= &fn_table
;
2072 ssh
->s
= new_connection(addr
, *realhost
, port
, 0, 1, nodelay
, (Plug
) ssh
);
2073 if ((err
= sk_socket_error(ssh
->s
))) {
2082 * Throttle or unthrottle the SSH connection.
2084 static void ssh1_throttle(Ssh ssh
, int adjust
)
2086 int old_count
= ssh
->v1_throttle_count
;
2087 ssh
->v1_throttle_count
+= adjust
;
2088 assert(ssh
->v1_throttle_count
>= 0);
2089 if (ssh
->v1_throttle_count
&& !old_count
) {
2090 sk_set_frozen(ssh
->s
, 1);
2091 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2092 sk_set_frozen(ssh
->s
, 0);
2097 * Throttle or unthrottle _all_ local data streams (for when sends
2098 * on the SSH connection itself back up).
2100 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2103 struct ssh_channel
*c
;
2105 if (enable
== ssh
->throttled_all
)
2107 ssh
->throttled_all
= enable
;
2108 ssh
->overall_bufsize
= bufsize
;
2111 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2113 case CHAN_MAINSESSION
:
2115 * This is treated separately, outside the switch.
2119 x11_override_throttle(c
->u
.x11
.s
, enable
);
2122 /* Agent channels require no buffer management. */
2125 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2132 * Username and password input, abstracted off into routines
2133 * reusable in several places - even between SSH1 and SSH2.
2136 /* Set up a username or password input loop on a given buffer. */
2137 void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2139 ssh
->userpass_input_buffer
= buffer
;
2140 ssh
->userpass_input_buflen
= buflen
;
2141 ssh
->userpass_input_bufpos
= 0;
2142 ssh
->userpass_input_echo
= echo
;
2146 * Process some terminal data in the course of username/password
2147 * input. Returns >0 for success (line of input returned in
2148 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2149 * for inconclusive (keep waiting for more input please).
2151 int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2156 switch (c
= *in
++) {
2159 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2160 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2165 if (ssh
->userpass_input_bufpos
> 0) {
2166 if (ssh
->userpass_input_echo
)
2167 c_write_str(ssh
, "\b \b");
2168 ssh
->userpass_input_bufpos
--;
2173 while (ssh
->userpass_input_bufpos
> 0) {
2174 if (ssh
->userpass_input_echo
)
2175 c_write_str(ssh
, "\b \b");
2176 ssh
->userpass_input_bufpos
--;
2184 if (((c
>= ' ' && c
<= '~') ||
2185 ((unsigned char) c
>= 160))
2186 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2187 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2188 if (ssh
->userpass_input_echo
)
2189 c_write(ssh
, &c
, 1);
2198 * Handle the key exchange and user authentication phases.
2200 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
2203 unsigned char cookie
[8];
2204 struct RSAKey servkey
, hostkey
;
2205 struct MD5Context md5c
;
2206 struct do_ssh1_login_state
{
2208 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2209 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2210 int tried_publickey
, tried_agent
;
2211 int tis_auth_refused
, ccard_auth_refused
;
2212 unsigned char session_id
[16];
2215 void *publickey_blob
;
2216 int publickey_bloblen
;
2222 unsigned char request
[5], *response
, *p
;
2231 crState(do_ssh1_login_state
);
2233 crBegin(ssh
->do_ssh1_login_crstate
);
2238 if (ssh
->pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2239 bombout(("Public key packet not received"));
2243 logevent("Received public keys");
2245 memcpy(cookie
, ssh
->pktin
.body
, 8);
2247 i
= makekey(ssh
->pktin
.body
+ 8, &servkey
, &s
->keystr1
, 0);
2248 j
= makekey(ssh
->pktin
.body
+ 8 + i
, &hostkey
, &s
->keystr2
, 0);
2251 * Log the host key fingerprint.
2255 logevent("Host key fingerprint is:");
2256 strcpy(logmsg
, " ");
2257 hostkey
.comment
= NULL
;
2258 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2259 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2263 ssh
->v1_remote_protoflags
= GET_32BIT(ssh
->pktin
.body
+ 8 + i
+ j
);
2264 s
->supported_ciphers_mask
= GET_32BIT(ssh
->pktin
.body
+ 12 + i
+ j
);
2265 s
->supported_auths_mask
= GET_32BIT(ssh
->pktin
.body
+ 16 + i
+ j
);
2267 ssh
->v1_local_protoflags
=
2268 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2269 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2272 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2273 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2274 MD5Update(&md5c
, ssh
->pktin
.body
, 8);
2275 MD5Final(s
->session_id
, &md5c
);
2277 for (i
= 0; i
< 32; i
++)
2278 ssh
->session_key
[i
] = random_byte();
2280 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2282 s
->rsabuf
= smalloc(s
->len
);
2284 fatalbox("Out of memory");
2287 * Verify the host key.
2291 * First format the key into a string.
2293 int len
= rsastr_len(&hostkey
);
2294 char fingerprint
[100];
2295 char *keystr
= smalloc(len
);
2297 fatalbox("Out of memory");
2298 rsastr_fmt(keystr
, &hostkey
);
2299 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2300 verify_ssh_host_key(ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2305 for (i
= 0; i
< 32; i
++) {
2306 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2308 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2311 if (hostkey
.bytes
> servkey
.bytes
) {
2312 rsaencrypt(s
->rsabuf
, 32, &servkey
);
2313 rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2315 rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2316 rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2319 logevent("Encrypted session key");
2322 int cipher_chosen
= 0, warn
= 0;
2323 char *cipher_string
= NULL
;
2325 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2326 int next_cipher
= cfg
.ssh_cipherlist
[i
];
2327 if (next_cipher
== CIPHER_WARN
) {
2328 /* If/when we choose a cipher, warn about it */
2330 } else if (next_cipher
== CIPHER_AES
) {
2331 /* XXX Probably don't need to mention this. */
2332 logevent("AES not supported in SSH1, skipping");
2334 switch (next_cipher
) {
2335 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2336 cipher_string
= "3DES"; break;
2337 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2338 cipher_string
= "Blowfish"; break;
2339 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2340 cipher_string
= "single-DES"; break;
2342 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2346 if (!cipher_chosen
) {
2347 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2348 bombout(("Server violates SSH 1 protocol by not "
2349 "supporting 3DES encryption"));
2351 /* shouldn't happen */
2352 bombout(("No supported ciphers found"));
2356 /* Warn about chosen cipher if necessary. */
2358 askcipher(cipher_string
, 0);
2361 switch (s
->cipher_type
) {
2362 case SSH_CIPHER_3DES
:
2363 logevent("Using 3DES encryption");
2365 case SSH_CIPHER_DES
:
2366 logevent("Using single-DES encryption");
2368 case SSH_CIPHER_BLOWFISH
:
2369 logevent("Using Blowfish encryption");
2373 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2374 PKT_CHAR
, s
->cipher_type
,
2375 PKT_DATA
, cookie
, 8,
2376 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2377 PKT_DATA
, s
->rsabuf
, s
->len
,
2378 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2380 logevent("Trying to enable encryption...");
2384 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2385 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2387 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2388 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2391 sprintf(buf
, "Initialised %.200s encryption", ssh
->cipher
->text_name
);
2395 ssh
->crcda_ctx
= crcda_make_context();
2396 logevent("Installing CRC compensation attack detector");
2400 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2401 bombout(("Encryption not successfully enabled"));
2405 logevent("Successfully started encryption");
2409 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2410 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2411 if (!ssh_get_line("login as: ",
2412 s
->username
, sizeof(s
->username
), FALSE
)) {
2414 * get_line failed to get a username.
2417 logevent("No username provided. Abandoning session.");
2418 ssh
->state
= SSH_STATE_CLOSED
;
2422 int ret
; /* need not be kept over crReturn */
2423 c_write_str(ssh
, "login as: ");
2426 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2428 crWaitUntil(!ispkt
);
2429 ret
= process_userpass_input(ssh
, in
, inlen
);
2433 c_write_str(ssh
, "\r\n");
2436 strncpy(s
->username
, cfg
.username
, sizeof(s
->username
));
2437 s
->username
[sizeof(s
->username
)-1] = '\0';
2440 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2442 char userlog
[22 + sizeof(s
->username
)];
2443 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2445 if (flags
& FLAG_INTERACTIVE
&&
2446 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2447 strcat(userlog
, "\r\n");
2448 c_write_str(ssh
, userlog
);
2455 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2456 /* We must not attempt PK auth. Pretend we've already tried it. */
2457 s
->tried_publickey
= s
->tried_agent
= 1;
2459 s
->tried_publickey
= s
->tried_agent
= 0;
2461 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2462 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2464 if (!rsakey_pubblob(cfg
.keyfile
,
2465 &s
->publickey_blob
, &s
->publickey_bloblen
))
2466 s
->publickey_blob
= NULL
;
2468 s
->publickey_blob
= NULL
;
2470 while (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2471 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2473 if (agent_exists() && !s
->tried_agent
) {
2475 * Attempt RSA authentication using Pageant.
2481 logevent("Pageant is running. Requesting keys.");
2483 /* Request the keys held by the agent. */
2484 PUT_32BIT(s
->request
, 1);
2485 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2486 agent_query(s
->request
, 5, &r
, &s
->responselen
);
2487 s
->response
= (unsigned char *) r
;
2488 if (s
->response
&& s
->responselen
>= 5 &&
2489 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2490 s
->p
= s
->response
+ 5;
2491 s
->nkeys
= GET_32BIT(s
->p
);
2495 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2498 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2501 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2504 if (s
->publickey_blob
&&
2505 !memcmp(s
->p
, s
->publickey_blob
,
2506 s
->publickey_bloblen
)) {
2507 logevent("This key matches configured key file");
2508 s
->tried_publickey
= 1;
2511 s
->p
+= ssh1_read_bignum(s
->p
, &s
->key
.exponent
);
2512 s
->p
+= ssh1_read_bignum(s
->p
, &s
->key
.modulus
);
2513 s
->commentlen
= GET_32BIT(s
->p
);
2516 s
->p
+= s
->commentlen
;
2517 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2518 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2520 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2521 logevent("Key refused");
2524 logevent("Received RSA challenge");
2525 ssh1_read_bignum(ssh
->pktin
.body
, &s
->challenge
);
2527 char *agentreq
, *q
, *ret
;
2530 len
= 1 + 4; /* message type, bit count */
2531 len
+= ssh1_bignum_length(s
->key
.exponent
);
2532 len
+= ssh1_bignum_length(s
->key
.modulus
);
2533 len
+= ssh1_bignum_length(s
->challenge
);
2534 len
+= 16; /* session id */
2535 len
+= 4; /* response format */
2536 agentreq
= smalloc(4 + len
);
2537 PUT_32BIT(agentreq
, len
);
2539 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2540 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2542 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2543 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2544 q
+= ssh1_write_bignum(q
, s
->challenge
);
2545 memcpy(q
, s
->session_id
, 16);
2547 PUT_32BIT(q
, 1); /* response format */
2548 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2552 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2553 logevent("Sending Pageant's response");
2554 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2555 PKT_DATA
, ret
+ 5, 16,
2559 if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
2561 ("Pageant's response accepted");
2562 if (flags
& FLAG_VERBOSE
) {
2563 c_write_str(ssh
, "Authenticated using"
2565 c_write(ssh
, s
->commentp
,
2567 c_write_str(ssh
, "\" from agent\r\n");
2572 ("Pageant's response not accepted");
2575 ("Pageant failed to answer challenge");
2579 logevent("No reply received from Pageant");
2582 freebn(s
->key
.exponent
);
2583 freebn(s
->key
.modulus
);
2584 freebn(s
->challenge
);
2592 if (*cfg
.keyfile
&& !s
->tried_publickey
)
2593 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2595 if (cfg
.try_tis_auth
&&
2596 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2597 !s
->tis_auth_refused
) {
2598 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2599 logevent("Requested TIS authentication");
2600 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
2602 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2603 logevent("TIS authentication declined");
2604 if (flags
& FLAG_INTERACTIVE
)
2605 c_write_str(ssh
, "TIS authentication refused.\r\n");
2606 s
->tis_auth_refused
= 1;
2609 int challengelen
= GET_32BIT(ssh
->pktin
.body
);
2610 logevent("Received TIS challenge");
2611 if (challengelen
> sizeof(s
->prompt
) - 1)
2612 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2613 memcpy(s
->prompt
, ssh
->pktin
.body
+ 4, challengelen
);
2614 /* Prompt heuristic comes from OpenSSH */
2615 strncpy(s
->prompt
+ challengelen
,
2616 memchr(s
->prompt
, '\n', challengelen
) ?
2617 "": "\r\nResponse: ",
2618 (sizeof s
->prompt
) - challengelen
);
2619 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
2622 if (cfg
.try_tis_auth
&&
2623 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2624 !s
->ccard_auth_refused
) {
2625 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2626 logevent("Requested CryptoCard authentication");
2627 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2629 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2630 logevent("CryptoCard authentication declined");
2631 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
2632 s
->ccard_auth_refused
= 1;
2635 int challengelen
= GET_32BIT(ssh
->pktin
.body
);
2636 logevent("Received CryptoCard challenge");
2637 if (challengelen
> sizeof(s
->prompt
) - 1)
2638 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2639 memcpy(s
->prompt
, ssh
->pktin
.body
+ 4, challengelen
);
2640 strncpy(s
->prompt
+ challengelen
,
2641 memchr(s
->prompt
, '\n', challengelen
) ?
2642 "" : "\r\nResponse: ",
2643 sizeof(s
->prompt
) - challengelen
);
2644 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
2647 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2648 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
2649 s
->username
, ssh
->savedhost
);
2651 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2652 char *comment
= NULL
;
2655 if (flags
& FLAG_VERBOSE
)
2656 c_write_str(ssh
, "Trying public key authentication.\r\n");
2657 sprintf(msgbuf
, "Trying public key \"%.200s\"", cfg
.keyfile
);
2659 type
= key_type(cfg
.keyfile
);
2660 if (type
!= SSH_KEYTYPE_SSH1
) {
2661 sprintf(msgbuf
, "Key is of wrong type (%s)",
2662 key_type_to_str(type
));
2664 c_write_str(ssh
, msgbuf
);
2665 c_write_str(ssh
, "\r\n");
2666 s
->tried_publickey
= 1;
2669 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
2670 if (flags
& FLAG_VERBOSE
)
2671 c_write_str(ssh
, "No passphrase required.\r\n");
2674 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
2679 * Show password prompt, having first obtained it via a TIS
2680 * or CryptoCard exchange if we're doing TIS or CryptoCard
2684 if (!ssh_get_line(s
->prompt
, s
->password
,
2685 sizeof(s
->password
), TRUE
)) {
2687 * get_line failed to get a password (for example
2688 * because one was supplied on the command line
2689 * which has already failed to work). Terminate.
2691 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
2692 PKT_STR
, "No more passwords available to try",
2694 logevent("Unable to authenticate");
2695 connection_fatal("Unable to authenticate");
2696 ssh
->state
= SSH_STATE_CLOSED
;
2700 /* Prompt may have come from server. We've munged it a bit, so
2701 * we know it to be zero-terminated at least once. */
2702 int ret
; /* need not be saved over crReturn */
2703 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
2706 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
2708 crWaitUntil(!ispkt
);
2709 ret
= process_userpass_input(ssh
, in
, inlen
);
2713 c_write_str(ssh
, "\r\n");
2717 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2719 * Try public key authentication with the specified
2722 s
->tried_publickey
= 1;
2725 int ret
= loadrsakey(cfg
.keyfile
, &s
->key
, s
->password
);
2727 c_write_str(ssh
, "Couldn't load private key from ");
2728 c_write_str(ssh
, cfg
.keyfile
);
2729 c_write_str(ssh
, ".\r\n");
2730 continue; /* go and try password */
2733 c_write_str(ssh
, "Wrong passphrase.\r\n");
2734 s
->tried_publickey
= 0;
2735 continue; /* try again */
2740 * Send a public key attempt.
2742 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2743 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2746 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2747 c_write_str(ssh
, "Server refused our public key.\r\n");
2748 continue; /* go and try password */
2750 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2751 bombout(("Bizarre response to offer of public key"));
2757 unsigned char buffer
[32];
2758 Bignum challenge
, response
;
2760 ssh1_read_bignum(ssh
->pktin
.body
, &challenge
);
2761 response
= rsadecrypt(challenge
, &s
->key
);
2762 freebn(s
->key
.private_exponent
);/* burn the evidence */
2764 for (i
= 0; i
< 32; i
++) {
2765 buffer
[i
] = bignum_byte(response
, 31 - i
);
2769 MD5Update(&md5c
, buffer
, 32);
2770 MD5Update(&md5c
, s
->session_id
, 16);
2771 MD5Final(buffer
, &md5c
);
2773 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2774 PKT_DATA
, buffer
, 16, PKT_END
);
2781 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2782 if (flags
& FLAG_VERBOSE
)
2783 c_write_str(ssh
, "Failed to authenticate with"
2784 " our public key.\r\n");
2785 continue; /* go and try password */
2786 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2787 bombout(("Bizarre response to RSA authentication response"));
2791 break; /* we're through! */
2793 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2795 * Defence against traffic analysis: we send a
2796 * whole bunch of packets containing strings of
2797 * different lengths. One of these strings is the
2798 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2799 * The others are all random data in
2800 * SSH1_MSG_IGNORE packets. This way a passive
2801 * listener can't tell which is the password, and
2802 * hence can't deduce the password length.
2804 * Anybody with a password length greater than 16
2805 * bytes is going to have enough entropy in their
2806 * password that a listener won't find it _that_
2807 * much help to know how long it is. So what we'll
2810 * - if password length < 16, we send 15 packets
2811 * containing string lengths 1 through 15
2813 * - otherwise, we let N be the nearest multiple
2814 * of 8 below the password length, and send 8
2815 * packets containing string lengths N through
2816 * N+7. This won't obscure the order of
2817 * magnitude of the password length, but it will
2818 * introduce a bit of extra uncertainty.
2820 * A few servers (the old 1.2.18 through 1.2.22)
2821 * can't deal with SSH1_MSG_IGNORE. For these
2822 * servers, we need an alternative defence. We make
2823 * use of the fact that the password is interpreted
2824 * as a C string: so we can append a NUL, then some
2827 * One server (a Cisco one) can deal with neither
2828 * SSH1_MSG_IGNORE _nor_ a padded password string.
2829 * For this server we are left with no defences
2830 * against password length sniffing.
2832 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2834 * The server can deal with SSH1_MSG_IGNORE, so
2835 * we can use the primary defence.
2837 int bottom
, top
, pwlen
, i
;
2840 pwlen
= strlen(s
->password
);
2842 bottom
= 0; /* zero length passwords are OK! :-) */
2845 bottom
= pwlen
& ~7;
2849 assert(pwlen
>= bottom
&& pwlen
<= top
);
2851 randomstr
= smalloc(top
+ 1);
2853 for (i
= bottom
; i
<= top
; i
++) {
2855 defer_packet(ssh
, s
->pwpkt_type
,
2856 PKT_STR
, s
->password
, PKT_END
);
2858 for (j
= 0; j
< i
; j
++) {
2860 randomstr
[j
] = random_byte();
2861 } while (randomstr
[j
] == '\0');
2863 randomstr
[i
] = '\0';
2864 defer_packet(ssh
, SSH1_MSG_IGNORE
,
2865 PKT_STR
, randomstr
, PKT_END
);
2868 logevent("Sending password with camouflage packets");
2869 ssh_pkt_defersend(ssh
);
2871 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2873 * The server can't deal with SSH1_MSG_IGNORE
2874 * but can deal with padded passwords, so we
2875 * can use the secondary defence.
2881 len
= strlen(s
->password
);
2882 if (len
< sizeof(string
)) {
2884 strcpy(string
, s
->password
);
2885 len
++; /* cover the zero byte */
2886 while (len
< sizeof(string
)) {
2887 string
[len
++] = (char) random_byte();
2892 logevent("Sending length-padded password");
2893 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
2894 PKT_DATA
, ss
, len
, PKT_END
);
2897 * The server has _both_
2898 * BUG_CHOKES_ON_SSH1_IGNORE and
2899 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2900 * therefore nothing we can do.
2903 len
= strlen(s
->password
);
2904 logevent("Sending unpadded password");
2905 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
2906 PKT_DATA
, s
->password
, len
, PKT_END
);
2909 send_packet(ssh
, s
->pwpkt_type
, PKT_STR
, s
->password
, PKT_END
);
2912 logevent("Sent password");
2913 memset(s
->password
, 0, strlen(s
->password
));
2915 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2916 if (flags
& FLAG_VERBOSE
)
2917 c_write_str(ssh
, "Access denied\r\n");
2918 logevent("Authentication refused");
2919 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2920 bombout(("Strange packet received, type %d", ssh
->pktin
.type
));
2925 logevent("Authentication successful");
2930 void sshfwd_close(struct ssh_channel
*c
)
2934 if (c
&& !c
->closes
) {
2936 * If the channel's remoteid is -1, we have sent
2937 * CHANNEL_OPEN for this channel, but it hasn't even been
2938 * acknowledged by the server. So we must set a close flag
2939 * on it now, and then when the server acks the channel
2940 * open, we can close it then.
2942 if (((int)c
->remoteid
) != -1) {
2943 if (ssh
->version
== 1) {
2944 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2947 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
2948 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
2952 c
->closes
= 1; /* sent MSG_CLOSE */
2953 if (c
->type
== CHAN_X11
) {
2955 logevent("Forwarded X11 connection terminated");
2956 } else if (c
->type
== CHAN_SOCKDATA
||
2957 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2959 logevent("Forwarded port closed");
2964 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
2968 if (ssh
->version
== 1) {
2969 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2970 PKT_INT
, c
->remoteid
,
2971 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
2973 * In SSH1 we can return 0 here - implying that forwarded
2974 * connections are never individually throttled - because
2975 * the only circumstance that can cause throttling will be
2976 * the whole SSH connection backing up, in which case
2977 * _everything_ will be throttled as a whole.
2981 ssh2_add_channel_data(c
, buf
, len
);
2982 return ssh2_try_send(c
);
2986 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
2990 if (ssh
->version
== 1) {
2991 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
2992 c
->v
.v1
.throttling
= 0;
2993 ssh1_throttle(ssh
, -1);
2996 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3000 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3002 crBegin(ssh
->ssh1_protocol_crstate
);
3006 while (!do_ssh1_login(ssh
, in
, inlen
, ispkt
)) {
3009 if (ssh
->state
== SSH_STATE_CLOSED
)
3012 if (cfg
.agentfwd
&& agent_exists()) {
3013 logevent("Requesting agent forwarding");
3014 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3018 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3019 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3020 bombout(("Protocol confusion"));
3022 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3023 logevent("Agent forwarding refused");
3025 logevent("Agent forwarding enabled");
3026 ssh
->agentfwd_enabled
= TRUE
;
3030 if (cfg
.x11_forward
) {
3031 char proto
[20], data
[64];
3032 logevent("Requesting X11 forwarding");
3033 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
3034 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3035 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3036 PKT_STR
, proto
, PKT_STR
, data
,
3037 PKT_INT
, 0, PKT_END
);
3039 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3040 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3045 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3046 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3047 bombout(("Protocol confusion"));
3049 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3050 logevent("X11 forwarding refused");
3052 logevent("X11 forwarding enabled");
3053 ssh
->X11_fwd_enabled
= TRUE
;
3060 int sport
,dport
,sserv
,dserv
;
3061 char sports
[256], dports
[256], host
[256];
3065 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3066 /* Add port forwardings. */
3067 ssh
->portfwd_strptr
= cfg
.portfwd
;
3068 while (*ssh
->portfwd_strptr
) {
3069 type
= *ssh
->portfwd_strptr
++;
3071 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t')
3072 sports
[n
++] = *ssh
->portfwd_strptr
++;
3074 if (*ssh
->portfwd_strptr
== '\t')
3075 ssh
->portfwd_strptr
++;
3077 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':')
3078 host
[n
++] = *ssh
->portfwd_strptr
++;
3080 if (*ssh
->portfwd_strptr
== ':')
3081 ssh
->portfwd_strptr
++;
3083 while (*ssh
->portfwd_strptr
)
3084 dports
[n
++] = *ssh
->portfwd_strptr
++;
3086 ssh
->portfwd_strptr
++;
3087 dport
= atoi(dports
);
3091 se
= getservbyname(dports
, NULL
);
3093 dport
= ntohs(se
->s_port
);
3096 "Service lookup failed for destination port \"%s\"",
3101 sport
= atoi(sports
);
3105 se
= getservbyname(sports
, NULL
);
3107 sport
= ntohs(se
->s_port
);
3110 "Service lookup failed for source port \"%s\"",
3115 if (sport
&& dport
) {
3117 pfd_addforward(host
, dport
, sport
, ssh
);
3118 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
3119 " %s:%.*s%.*s%d%.*s",
3120 sserv ?
strlen(sports
) : 0, sports
,
3121 sserv
, "(", sport
, sserv
, ")",
3123 dserv ?
strlen(dports
) : 0, dports
,
3124 dserv
, "(", dport
, dserv
, ")");
3127 struct ssh_rportfwd
*pf
;
3128 pf
= smalloc(sizeof(*pf
));
3129 strcpy(pf
->dhost
, host
);
3131 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3133 "Duplicate remote port forwarding to %s:%d",
3138 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
3139 " forward to %s:%.*s%.*s%d%.*s",
3140 sserv ?
strlen(sports
) : 0, sports
,
3141 sserv
, "(", sport
, sserv
, ")",
3143 dserv ?
strlen(dports
) : 0, dports
,
3144 dserv
, "(", dport
, dserv
, ")");
3146 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3154 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3155 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3156 bombout(("Protocol confusion"));
3158 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3159 c_write_str(ssh
, "Server refused port"
3162 logevent("Remote port forwarding enabled");
3170 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
3171 PKT_STR
, cfg
.termtype
,
3172 PKT_INT
, ssh
->term_height
,
3173 PKT_INT
, ssh
->term_width
,
3174 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3175 ssh
->state
= SSH_STATE_INTERMED
;
3179 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3180 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3181 bombout(("Protocol confusion"));
3183 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3184 c_write_str(ssh
, "Server refused to allocate pty\r\n");
3185 ssh
->editing
= ssh
->echoing
= 1;
3187 logevent("Allocated pty");
3189 ssh
->editing
= ssh
->echoing
= 1;
3192 if (cfg
.compression
) {
3193 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3197 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3198 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3199 bombout(("Protocol confusion"));
3201 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3202 c_write_str(ssh
, "Server refused to compress\r\n");
3204 logevent("Started compression");
3205 ssh
->v1_compressing
= TRUE
;
3206 ssh
->cs_comp_ctx
= zlib_compress_init();
3207 logevent("Initialised zlib (RFC1950) compression");
3208 ssh
->sc_comp_ctx
= zlib_decompress_init();
3209 logevent("Initialised zlib (RFC1950) decompression");
3213 * Start the shell or command.
3215 * Special case: if the first-choice command is an SSH2
3216 * subsystem (hence not usable here) and the second choice
3217 * exists, we fall straight back to that.
3220 char *cmd
= cfg
.remote_cmd_ptr
;
3222 if (cfg
.ssh_subsys
&& cfg
.remote_cmd_ptr2
) {
3223 cmd
= cfg
.remote_cmd_ptr2
;
3224 ssh
->fallback_cmd
= TRUE
;
3227 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3229 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3230 logevent("Started session");
3233 ssh
->state
= SSH_STATE_SESSION
;
3234 if (ssh
->size_needed
)
3235 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
3236 if (ssh
->eof_needed
)
3237 ssh_special(ssh
, TS_EOF
);
3240 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
3242 ssh
->channels
= newtree234(ssh_channelcmp
);
3246 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3247 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3248 long len
= GET_32BIT(ssh
->pktin
.body
);
3250 from_backend(ssh
->frontend
,
3251 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3252 ssh
->pktin
.body
+ 4, len
);
3253 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3254 ssh
->v1_stdout_throttling
= 1;
3255 ssh1_throttle(ssh
, +1);
3257 } else if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
3258 ssh
->state
= SSH_STATE_CLOSED
;
3259 logevent("Received disconnect request");
3261 } else if (ssh
->pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3262 /* Remote side is trying to open a channel to talk to our
3263 * X-Server. Give them back a local channel number. */
3264 struct ssh_channel
*c
;
3266 logevent("Received X11 connect request");
3267 /* Refuse if X11 forwarding is disabled. */
3268 if (!ssh
->X11_fwd_enabled
) {
3269 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3270 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3271 logevent("Rejected X11 connect request");
3273 c
= smalloc(sizeof(struct ssh_channel
));
3276 if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3277 logevent("opening X11 forward connection failed");
3279 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3280 PKT_INT
, GET_32BIT(ssh
->pktin
.body
),
3284 ("opening X11 forward connection succeeded");
3285 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3286 c
->localid
= alloc_channel_id(ssh
);
3288 c
->v
.v1
.throttling
= 0;
3289 c
->type
= CHAN_X11
; /* identify channel type */
3290 add234(ssh
->channels
, c
);
3291 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3292 PKT_INT
, c
->remoteid
, PKT_INT
,
3293 c
->localid
, PKT_END
);
3294 logevent("Opened X11 forward channel");
3297 } else if (ssh
->pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3298 /* Remote side is trying to open a channel to talk to our
3299 * agent. Give them back a local channel number. */
3300 struct ssh_channel
*c
;
3302 /* Refuse if agent forwarding is disabled. */
3303 if (!ssh
->agentfwd_enabled
) {
3304 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3305 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3307 c
= smalloc(sizeof(struct ssh_channel
));
3309 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3310 c
->localid
= alloc_channel_id(ssh
);
3312 c
->v
.v1
.throttling
= 0;
3313 c
->type
= CHAN_AGENT
; /* identify channel type */
3314 c
->u
.a
.lensofar
= 0;
3315 add234(ssh
->channels
, c
);
3316 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3317 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3320 } else if (ssh
->pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3321 /* Remote side is trying to open a channel to talk to a
3322 * forwarded port. Give them back a local channel number. */
3323 struct ssh_channel
*c
;
3324 struct ssh_rportfwd pf
;
3326 char host
[256], buf
[1024];
3328 c
= smalloc(sizeof(struct ssh_channel
));
3331 hostsize
= GET_32BIT(ssh
->pktin
.body
+4);
3332 for(h
= host
, p
= ssh
->pktin
.body
+8; hostsize
!= 0; hostsize
--) {
3333 if (h
+1 < host
+sizeof(host
))
3338 port
= GET_32BIT(p
);
3340 strcpy(pf
.dhost
, host
);
3343 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3344 sprintf(buf
, "Rejected remote port open request for %s:%d",
3347 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3348 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3350 sprintf(buf
, "Received remote port open request for %s:%d",
3353 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
);
3356 sprintf(buf
, "Port open failed: %s", e
);
3359 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3360 PKT_INT
, GET_32BIT(ssh
->pktin
.body
),
3363 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3364 c
->localid
= alloc_channel_id(ssh
);
3366 c
->v
.v1
.throttling
= 0;
3367 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3368 add234(ssh
->channels
, c
);
3369 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3370 PKT_INT
, c
->remoteid
, PKT_INT
,
3371 c
->localid
, PKT_END
);
3372 logevent("Forwarded port opened successfully");
3376 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3377 unsigned int remoteid
= GET_32BIT(ssh
->pktin
.body
);
3378 unsigned int localid
= GET_32BIT(ssh
->pktin
.body
+4);
3379 struct ssh_channel
*c
;
3381 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3382 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3383 c
->remoteid
= localid
;
3384 c
->type
= CHAN_SOCKDATA
;
3385 c
->v
.v1
.throttling
= 0;
3386 pfd_confirm(c
->u
.pfd
.s
);
3389 if (c
&& c
->closes
) {
3391 * We have a pending close on this channel,
3392 * which we decided on before the server acked
3393 * the channel open. So now we know the
3394 * remoteid, we can close it again.
3396 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3397 PKT_INT
, c
->remoteid
, PKT_END
);
3400 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3401 unsigned int remoteid
= GET_32BIT(ssh
->pktin
.body
);
3402 unsigned int localid
= GET_32BIT(ssh
->pktin
.body
+4);
3403 struct ssh_channel
*c
;
3405 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3406 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3407 logevent("Forwarded connection refused by server");
3408 pfd_close(c
->u
.pfd
.s
);
3409 del234(ssh
->channels
, c
);
3413 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3414 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3415 /* Remote side closes a channel. */
3416 unsigned i
= GET_32BIT(ssh
->pktin
.body
);
3417 struct ssh_channel
*c
;
3418 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3419 if (c
&& ((int)c
->remoteid
) != -1) {
3422 (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3424 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3425 logevent("Forwarded X11 connection terminated");
3426 assert(c
->u
.x11
.s
!= NULL
);
3427 x11_close(c
->u
.x11
.s
);
3430 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3431 logevent("Forwarded port closed");
3432 assert(c
->u
.pfd
.s
!= NULL
);
3433 pfd_close(c
->u
.pfd
.s
);
3437 c
->closes
|= (closetype
<< 2); /* seen this message */
3438 if (!(c
->closes
& closetype
)) {
3439 send_packet(ssh
, ssh
->pktin
.type
, PKT_INT
, c
->remoteid
,
3441 c
->closes
|= closetype
; /* sent it too */
3444 if (c
->closes
== 15) {
3445 del234(ssh
->channels
, c
);
3449 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
3450 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3451 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3454 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3455 /* Data sent down one of our channels. */
3456 int i
= GET_32BIT(ssh
->pktin
.body
);
3457 int len
= GET_32BIT(ssh
->pktin
.body
+ 4);
3458 unsigned char *p
= ssh
->pktin
.body
+ 8;
3459 struct ssh_channel
*c
;
3460 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3465 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
3468 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
3471 /* Data for an agent message. Buffer it. */
3473 if (c
->u
.a
.lensofar
< 4) {
3474 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3475 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3479 c
->u
.a
.lensofar
+= l
;
3481 if (c
->u
.a
.lensofar
== 4) {
3483 4 + GET_32BIT(c
->u
.a
.msglen
);
3484 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3485 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3487 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3489 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3491 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3495 c
->u
.a
.lensofar
+= l
;
3497 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3498 void *reply
, *sentreply
;
3500 agent_query(c
->u
.a
.message
,
3501 c
->u
.a
.totallen
, &reply
,
3506 /* Fake SSH_AGENT_FAILURE. */
3507 sentreply
= "\0\0\0\1\5";
3510 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3511 PKT_INT
, c
->remoteid
,
3513 PKT_DATA
, sentreply
, replylen
,
3517 sfree(c
->u
.a
.message
);
3518 c
->u
.a
.lensofar
= 0;
3521 bufsize
= 0; /* agent channels never back up */
3524 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3525 c
->v
.v1
.throttling
= 1;
3526 ssh1_throttle(ssh
, +1);
3529 } else if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
3530 /* may be from EXEC_SHELL on some servers */
3531 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3532 /* may be from EXEC_SHELL on some servers
3533 * if no pty is available or in other odd cases. Ignore */
3534 } else if (ssh
->pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3536 ssh
->exitcode
= GET_32BIT(ssh
->pktin
.body
);
3537 sprintf(buf
, "Server sent command exit status %d",
3540 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3542 * In case `helpful' firewalls or proxies tack
3543 * extra human-readable text on the end of the
3544 * session which we might mistake for another
3545 * encrypted packet, we close the session once
3546 * we've sent EXIT_CONFIRMATION.
3548 ssh
->state
= SSH_STATE_CLOSED
;
3551 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
3556 int len
= min(inlen
, 512);
3557 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
,
3558 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3569 * Utility routine for decoding comma-separated strings in KEXINIT.
3571 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3573 int needlen
= strlen(needle
);
3576 * Is it at the start of the string?
3578 if (haylen
>= needlen
&& /* haystack is long enough */
3579 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3580 (haylen
== needlen
|| haystack
[needlen
] == ',')
3581 /* either , or EOS follows */
3585 * If not, search for the next comma and resume after that.
3586 * If no comma found, terminate.
3588 while (haylen
> 0 && *haystack
!= ',')
3589 haylen
--, haystack
++;
3592 haylen
--, haystack
++; /* skip over comma itself */
3597 * SSH2 key creation method.
3599 static void ssh2_mkkey(Ssh ssh
, Bignum K
, char *H
, char *sessid
, char chr
,
3603 /* First 20 bytes. */
3605 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3607 SHA_Bytes(&s
, H
, 20);
3608 SHA_Bytes(&s
, &chr
, 1);
3609 SHA_Bytes(&s
, sessid
, 20);
3610 SHA_Final(&s
, keyspace
);
3611 /* Next 20 bytes. */
3613 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3615 SHA_Bytes(&s
, H
, 20);
3616 SHA_Bytes(&s
, keyspace
, 20);
3617 SHA_Final(&s
, keyspace
+ 20);
3621 * Handle the SSH2 transport layer.
3623 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3625 struct do_ssh2_transport_state
{
3626 int nbits
, pbits
, warn
;
3627 Bignum p
, g
, e
, f
, K
;
3628 int kex_init_value
, kex_reply_value
;
3629 const struct ssh_mac
**maclist
;
3631 const struct ssh2_cipher
*cscipher_tobe
;
3632 const struct ssh2_cipher
*sccipher_tobe
;
3633 const struct ssh_mac
*csmac_tobe
;
3634 const struct ssh_mac
*scmac_tobe
;
3635 const struct ssh_compress
*cscomp_tobe
;
3636 const struct ssh_compress
*sccomp_tobe
;
3637 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3638 int hostkeylen
, siglen
;
3639 void *hkey
; /* actual host key */
3640 unsigned char exchange_hash
[20];
3641 int n_preferred_ciphers
;
3642 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3643 const struct ssh_compress
*preferred_comp
;
3646 crState(do_ssh2_transport_state
);
3648 crBegin(ssh
->do_ssh2_transport_crstate
);
3650 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
3651 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
3652 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
3660 * Set up the preferred ciphers. (NULL => warn below here)
3662 s
->n_preferred_ciphers
= 0;
3663 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3664 switch (cfg
.ssh_cipherlist
[i
]) {
3665 case CIPHER_BLOWFISH
:
3666 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
3669 if (cfg
.ssh2_des_cbc
) {
3670 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
3674 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
3677 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
3680 /* Flag for later. Don't bother if it's the last in
3682 if (i
< CIPHER_MAX
- 1) {
3683 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
3691 * Set up preferred compression.
3693 if (cfg
.compression
)
3694 s
->preferred_comp
= &ssh_zlib
;
3696 s
->preferred_comp
= &ssh_comp_none
;
3699 * Be prepared to work around the buggy MAC problem.
3701 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
3702 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
3704 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
3708 int i
, j
, cipherstr_started
;
3711 * Construct and send our key exchange packet.
3713 ssh2_pkt_init(ssh
, SSH2_MSG_KEXINIT
);
3714 for (i
= 0; i
< 16; i
++)
3715 ssh2_pkt_addbyte(ssh
, (unsigned char) random_byte());
3716 /* List key exchange algorithms. */
3717 ssh2_pkt_addstring_start(ssh
);
3718 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3719 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3720 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
3722 ssh2_pkt_addstring_str(ssh
, kex_algs
[i
]->name
);
3723 if (i
< lenof(kex_algs
) - 1)
3724 ssh2_pkt_addstring_str(ssh
, ",");
3726 /* List server host key algorithms. */
3727 ssh2_pkt_addstring_start(ssh
);
3728 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3729 ssh2_pkt_addstring_str(ssh
, hostkey_algs
[i
]->name
);
3730 if (i
< lenof(hostkey_algs
) - 1)
3731 ssh2_pkt_addstring_str(ssh
, ",");
3733 /* List client->server encryption algorithms. */
3734 ssh2_pkt_addstring_start(ssh
);
3735 cipherstr_started
= 0;
3736 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3737 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3738 if (!c
) continue; /* warning flag */
3739 for (j
= 0; j
< c
->nciphers
; j
++) {
3740 if (cipherstr_started
)
3741 ssh2_pkt_addstring_str(ssh
, ",");
3742 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
3743 cipherstr_started
= 1;
3746 /* List server->client encryption algorithms. */
3747 ssh2_pkt_addstring_start(ssh
);
3748 cipherstr_started
= 0;
3749 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3750 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3751 if (!c
) continue; /* warning flag */
3752 for (j
= 0; j
< c
->nciphers
; j
++) {
3753 if (cipherstr_started
)
3754 ssh2_pkt_addstring_str(ssh
, ",");
3755 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
3756 cipherstr_started
= 1;
3759 /* List client->server MAC algorithms. */
3760 ssh2_pkt_addstring_start(ssh
);
3761 for (i
= 0; i
< s
->nmacs
; i
++) {
3762 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
3763 if (i
< s
->nmacs
- 1)
3764 ssh2_pkt_addstring_str(ssh
, ",");
3766 /* List server->client MAC algorithms. */
3767 ssh2_pkt_addstring_start(ssh
);
3768 for (i
= 0; i
< s
->nmacs
; i
++) {
3769 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
3770 if (i
< s
->nmacs
- 1)
3771 ssh2_pkt_addstring_str(ssh
, ",");
3773 /* List client->server compression algorithms. */
3774 ssh2_pkt_addstring_start(ssh
);
3775 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3776 const struct ssh_compress
*c
=
3777 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3778 ssh2_pkt_addstring_str(ssh
, c
->name
);
3779 if (i
< lenof(compressions
))
3780 ssh2_pkt_addstring_str(ssh
, ",");
3782 /* List server->client compression algorithms. */
3783 ssh2_pkt_addstring_start(ssh
);
3784 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3785 const struct ssh_compress
*c
=
3786 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3787 ssh2_pkt_addstring_str(ssh
, c
->name
);
3788 if (i
< lenof(compressions
))
3789 ssh2_pkt_addstring_str(ssh
, ",");
3791 /* List client->server languages. Empty list. */
3792 ssh2_pkt_addstring_start(ssh
);
3793 /* List server->client languages. Empty list. */
3794 ssh2_pkt_addstring_start(ssh
);
3795 /* First KEX packet does _not_ follow, because we're not that brave. */
3796 ssh2_pkt_addbool(ssh
, FALSE
);
3798 ssh2_pkt_adduint32(ssh
, 0);
3801 ssh
->exhash
= ssh
->exhashbase
;
3802 sha_string(&ssh
->exhash
, ssh
->pktout
.data
+ 5, ssh
->pktout
.length
- 5);
3808 sha_string(&ssh
->exhash
, ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5);
3811 * Now examine the other side's KEXINIT to see what we're up
3818 if (ssh
->pktin
.type
!= SSH2_MSG_KEXINIT
) {
3819 bombout(("expected key exchange packet from server"));
3823 ssh
->hostkey
= NULL
;
3824 s
->cscipher_tobe
= NULL
;
3825 s
->sccipher_tobe
= NULL
;
3826 s
->csmac_tobe
= NULL
;
3827 s
->scmac_tobe
= NULL
;
3828 s
->cscomp_tobe
= NULL
;
3829 s
->sccomp_tobe
= NULL
;
3830 ssh
->pktin
.savedpos
+= 16; /* skip garbage cookie */
3831 ssh2_pkt_getstring(ssh
, &str
, &len
); /* key exchange algorithms */
3832 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3833 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3834 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
3836 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3837 ssh
->kex
= kex_algs
[i
];
3841 ssh2_pkt_getstring(ssh
, &str
, &len
); /* host key algorithms */
3842 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3843 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3844 ssh
->hostkey
= hostkey_algs
[i
];
3848 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server cipher */
3850 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3851 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3855 for (j
= 0; j
< c
->nciphers
; j
++) {
3856 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3857 s
->cscipher_tobe
= c
->list
[j
];
3862 if (s
->cscipher_tobe
) {
3864 askcipher(s
->cscipher_tobe
->name
, 1);
3868 if (!s
->cscipher_tobe
) {
3869 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str
));
3873 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client cipher */
3875 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3876 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3880 for (j
= 0; j
< c
->nciphers
; j
++) {
3881 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3882 s
->sccipher_tobe
= c
->list
[j
];
3887 if (s
->sccipher_tobe
) {
3889 askcipher(s
->sccipher_tobe
->name
, 2);
3893 if (!s
->sccipher_tobe
) {
3894 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str
));
3898 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server mac */
3899 for (i
= 0; i
< s
->nmacs
; i
++) {
3900 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
3901 s
->csmac_tobe
= s
->maclist
[i
];
3905 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client mac */
3906 for (i
= 0; i
< s
->nmacs
; i
++) {
3907 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
3908 s
->scmac_tobe
= s
->maclist
[i
];
3912 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server compression */
3913 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3914 const struct ssh_compress
*c
=
3915 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3916 if (in_commasep_string(c
->name
, str
, len
)) {
3921 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client compression */
3922 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3923 const struct ssh_compress
*c
=
3924 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3925 if (in_commasep_string(c
->name
, str
, len
)) {
3933 * Work out the number of bits of key we will need from the key
3934 * exchange. We start with the maximum key length of either
3940 csbits
= s
->cscipher_tobe
->keylen
;
3941 scbits
= s
->sccipher_tobe
->keylen
;
3942 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
3944 /* The keys only have 160-bit entropy, since they're based on
3945 * a SHA-1 hash. So cap the key size at 160 bits. */
3950 * If we're doing Diffie-Hellman group exchange, start by
3951 * requesting a group.
3953 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
3954 logevent("Doing Diffie-Hellman group exchange");
3955 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
3957 * Work out how big a DH group we will need to allow that
3960 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
3961 ssh2_pkt_init(ssh
, SSH2_MSG_KEX_DH_GEX_REQUEST
);
3962 ssh2_pkt_adduint32(ssh
, s
->pbits
);
3966 if (ssh
->pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
3967 bombout(("expected key exchange group packet from server"));
3970 s
->p
= ssh2_pkt_getmp(ssh
);
3971 s
->g
= ssh2_pkt_getmp(ssh
);
3972 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
3973 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
3974 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
3976 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
3977 ssh
->kex_ctx
= dh_setup_group1();
3978 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
3979 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
3982 logevent("Doing Diffie-Hellman key exchange");
3984 * Now generate and send e for Diffie-Hellman.
3986 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
3987 ssh2_pkt_init(ssh
, s
->kex_init_value
);
3988 ssh2_pkt_addmp(ssh
, s
->e
);
3992 if (ssh
->pktin
.type
!= s
->kex_reply_value
) {
3993 bombout(("expected key exchange reply packet from server"));
3996 ssh2_pkt_getstring(ssh
, &s
->hostkeydata
, &s
->hostkeylen
);
3997 s
->f
= ssh2_pkt_getmp(ssh
);
3998 ssh2_pkt_getstring(ssh
, &s
->sigdata
, &s
->siglen
);
4000 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4002 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4003 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4004 sha_uint32(&ssh
->exhash
, s
->pbits
);
4005 sha_mpint(&ssh
->exhash
, s
->p
);
4006 sha_mpint(&ssh
->exhash
, s
->g
);
4008 sha_mpint(&ssh
->exhash
, s
->e
);
4009 sha_mpint(&ssh
->exhash
, s
->f
);
4010 sha_mpint(&ssh
->exhash
, s
->K
);
4011 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4013 dh_cleanup(ssh
->kex_ctx
);
4016 debug(("Exchange hash is:\n"));
4017 dmemdump(s
->exchange_hash
, 20);
4020 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4022 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4023 s
->exchange_hash
, 20)) {
4024 bombout(("Server's host key did not match the signature supplied"));
4029 * Authenticate remote host: verify host key. (We've already
4030 * checked the signature of the exchange hash.)
4032 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4033 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4034 verify_ssh_host_key(ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4035 s
->keystr
, s
->fingerprint
);
4036 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4037 logevent("Host key fingerprint is:");
4038 logevent(s
->fingerprint
);
4040 sfree(s
->fingerprint
);
4042 ssh
->hostkey
->freekey(s
->hkey
);
4045 * Send SSH2_MSG_NEWKEYS.
4047 ssh2_pkt_init(ssh
, SSH2_MSG_NEWKEYS
);
4051 * Expect SSH2_MSG_NEWKEYS from server.
4054 if (ssh
->pktin
.type
!= SSH2_MSG_NEWKEYS
) {
4055 bombout(("expected new-keys packet from server"));
4060 * Create and initialise session keys.
4062 if (ssh
->cs_cipher_ctx
)
4063 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4064 ssh
->cscipher
= s
->cscipher_tobe
;
4065 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4067 if (ssh
->sc_cipher_ctx
)
4068 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4069 ssh
->sccipher
= s
->sccipher_tobe
;
4070 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4072 if (ssh
->cs_mac_ctx
)
4073 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4074 ssh
->csmac
= s
->csmac_tobe
;
4075 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4077 if (ssh
->sc_mac_ctx
)
4078 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4079 ssh
->scmac
= s
->scmac_tobe
;
4080 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4082 if (ssh
->cs_comp_ctx
)
4083 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4084 ssh
->cscomp
= s
->cscomp_tobe
;
4085 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4087 if (ssh
->sc_comp_ctx
)
4088 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4089 ssh
->sccomp
= s
->sccomp_tobe
;
4090 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4093 * Set IVs after keys. Here we use the exchange hash from the
4094 * _first_ key exchange.
4097 unsigned char keyspace
[40];
4099 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4100 sizeof(s
->exchange_hash
));
4101 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4102 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4103 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4104 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4105 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4106 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4107 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4108 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4109 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4110 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4111 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4112 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4116 sprintf(buf
, "Initialised %.200s client->server encryption",
4117 ssh
->cscipher
->text_name
);
4119 sprintf(buf
, "Initialised %.200s server->client encryption",
4120 ssh
->sccipher
->text_name
);
4122 if (ssh
->cscomp
->text_name
) {
4123 sprintf(buf
, "Initialised %.200s compression",
4124 ssh
->cscomp
->text_name
);
4127 if (ssh
->sccomp
->text_name
) {
4128 sprintf(buf
, "Initialised %.200s decompression",
4129 ssh
->sccomp
->text_name
);
4136 * If this is the first key exchange phase, we must pass the
4137 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4138 * wants to see it but because it will need time to initialise
4139 * itself before it sees an actual packet. In subsequent key
4140 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4141 * it would only confuse the layer above.
4143 if (!s
->first_kex
) {
4149 * Now we're encrypting. Begin returning 1 to the protocol main
4150 * function so that other things can run on top of the
4151 * transport. If we ever see a KEXINIT, we must go back to the
4154 while (!(ispkt
&& ssh
->pktin
.type
== SSH2_MSG_KEXINIT
)) {
4157 logevent("Server initiated key re-exchange");
4158 goto begin_key_exchange
;
4164 * Add data to an SSH2 channel output buffer.
4166 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4169 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4173 * Attempt to send data on an SSH2 channel.
4175 static int ssh2_try_send(struct ssh_channel
*c
)
4179 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4182 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4183 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4184 len
= c
->v
.v2
.remwindow
;
4185 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4186 len
= c
->v
.v2
.remmaxpkt
;
4187 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_DATA
);
4188 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4189 ssh2_pkt_addstring_start(ssh
);
4190 ssh2_pkt_addstring_data(ssh
, data
, len
);
4192 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4193 c
->v
.v2
.remwindow
-= len
;
4197 * After having sent as much data as we can, return the amount
4200 return bufchain_size(&c
->v
.v2
.outbuffer
);
4204 * Potentially enlarge the window on an SSH2 channel.
4206 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4211 * Never send WINDOW_ADJUST for a channel that the remote side
4212 * already thinks it's closed; there's no point, since it won't
4213 * be sending any more data anyway.
4218 if (newwin
> c
->v
.v2
.locwindow
) {
4219 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4220 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4221 ssh2_pkt_adduint32(ssh
, newwin
- c
->v
.v2
.locwindow
);
4223 c
->v
.v2
.locwindow
= newwin
;
4228 * Handle the SSH2 userauth and connection layers.
4230 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4232 struct do_ssh2_authconn_state
{
4234 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4236 AUTH_KEYBOARD_INTERACTIVE
4240 AUTH_TYPE_PUBLICKEY
,
4241 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4242 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4244 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4245 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4247 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4248 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4249 int kbd_inter_running
;
4251 int num_prompts
, curr_prompt
, echo
;
4256 void *publickey_blob
;
4257 int publickey_bloblen
;
4258 unsigned char request
[5], *response
, *p
;
4262 char *pkblob
, *alg
, *commentp
;
4263 int pklen
, alglen
, commentlen
;
4264 int siglen
, retlen
, len
;
4265 char *q
, *agentreq
, *ret
;
4268 crState(do_ssh2_authconn_state
);
4270 crBegin(ssh
->do_ssh2_authconn_crstate
);
4273 * Request userauth protocol, and await a response to it.
4275 ssh2_pkt_init(ssh
, SSH2_MSG_SERVICE_REQUEST
);
4276 ssh2_pkt_addstring(ssh
, "ssh-userauth");
4278 crWaitUntilV(ispkt
);
4279 if (ssh
->pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4280 bombout(("Server refused user authentication protocol"));
4285 * We repeat this whole loop, including the username prompt,
4286 * until we manage a successful authentication. If the user
4287 * types the wrong _password_, they can be sent back to the
4288 * beginning to try another username, if this is configured on.
4289 * (If they specify a username in the config, they are never
4290 * asked, even if they do give a wrong password.)
4292 * I think this best serves the needs of
4294 * - the people who have no configuration, no keys, and just
4295 * want to try repeated (username,password) pairs until they
4296 * type both correctly
4298 * - people who have keys and configuration but occasionally
4299 * need to fall back to passwords
4301 * - people with a key held in Pageant, who might not have
4302 * logged in to a particular machine before; so they want to
4303 * type a username, and then _either_ their key will be
4304 * accepted, _or_ they will type a password. If they mistype
4305 * the username they will want to be able to get back and
4308 s
->username
[0] = '\0';
4309 s
->got_username
= FALSE
;
4314 if (s
->got_username
&& !cfg
.change_username
) {
4316 * We got a username last time round this loop, and
4317 * with change_username turned off we don't try to get
4320 } else if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
4321 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4322 if (!ssh_get_line("login as: ",
4323 s
->username
, sizeof(s
->username
), FALSE
)) {
4325 * get_line failed to get a username.
4328 logevent("No username provided. Abandoning session.");
4329 ssh
->state
= SSH_STATE_CLOSED
;
4333 int ret
; /* need not be saved across crReturn */
4334 c_write_str(ssh
, "login as: ");
4336 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
4338 crWaitUntilV(!ispkt
);
4339 ret
= process_userpass_input(ssh
, in
, inlen
);
4344 c_write_str(ssh
, "\r\n");
4345 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
4348 strncpy(s
->username
, cfg
.username
, sizeof(s
->username
));
4349 s
->username
[sizeof(s
->username
)-1] = '\0';
4350 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4351 sprintf(stuff
, "Using username \"%s\".\r\n", s
->username
);
4352 c_write_str(ssh
, stuff
);
4355 s
->got_username
= TRUE
;
4358 * Send an authentication request using method "none": (a)
4359 * just in case it succeeds, and (b) so that we know what
4360 * authentication methods we can usefully try next.
4362 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4364 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4365 ssh2_pkt_addstring(ssh
, s
->username
);
4366 ssh2_pkt_addstring(ssh
, "ssh-connection");/* service requested */
4367 ssh2_pkt_addstring(ssh
, "none"); /* method */
4369 s
->type
= AUTH_TYPE_NONE
;
4371 s
->we_are_in
= FALSE
;
4373 s
->tried_pubkey_config
= FALSE
;
4374 s
->tried_agent
= FALSE
;
4375 s
->tried_keyb_inter
= FALSE
;
4376 s
->kbd_inter_running
= FALSE
;
4377 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4380 logeventf("Reading private key file \"%.150s\"", cfg
.keyfile
);
4381 keytype
= key_type(cfg
.keyfile
);
4382 if (keytype
== SSH_KEYTYPE_SSH2
) {
4384 ssh2_userkey_loadpub(cfg
.keyfile
, NULL
,
4385 &s
->publickey_bloblen
);
4388 logeventf("Unable to use this key file (%s)",
4389 key_type_to_str(keytype
));
4390 sprintf(msgbuf
, "Unable to use key file \"%.150s\" (%s)\r\n",
4391 cfg
.keyfile
, key_type_to_str(keytype
));
4392 c_write_str(ssh
, msgbuf
);
4393 s
->publickey_blob
= NULL
;
4396 s
->publickey_blob
= NULL
;
4400 * Wait for the result of the last authentication request.
4403 crWaitUntilV(ispkt
);
4404 while (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4408 * Don't show the banner if we're operating in
4409 * non-verbose non-interactive mode. (It's probably
4410 * a script, which means nobody will read the
4411 * banner _anyway_, and moreover the printing of
4412 * the banner will screw up processing on the
4413 * output of (say) plink.)
4415 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4416 ssh2_pkt_getstring(ssh
, &banner
, &size
);
4418 c_write_untrusted(ssh
, banner
, size
);
4420 crWaitUntilV(ispkt
);
4422 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4423 logevent("Access granted");
4424 s
->we_are_in
= TRUE
;
4428 if (s
->kbd_inter_running
&&
4429 ssh
->pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4431 * This is either a further set-of-prompts packet
4432 * in keyboard-interactive authentication, or it's
4433 * the same one and we came back here with `gotit'
4434 * set. In the former case, we must reset the
4435 * curr_prompt variable.
4439 } else if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4440 bombout(("Strange packet received during authentication: type %d",
4448 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4449 * we can look at the string in it and know what we can
4450 * helpfully try next.
4452 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4455 ssh2_pkt_getstring(ssh
, &methods
, &methlen
);
4456 s
->kbd_inter_running
= FALSE
;
4457 if (!ssh2_pkt_getbool(ssh
)) {
4459 * We have received an unequivocal Access
4460 * Denied. This can translate to a variety of
4463 * - if we'd just tried "none" authentication,
4464 * it's not worth printing anything at all
4466 * - if we'd just tried a public key _offer_,
4467 * the message should be "Server refused our
4468 * key" (or no message at all if the key
4469 * came from Pageant)
4471 * - if we'd just tried anything else, the
4472 * message really should be "Access denied".
4474 * Additionally, if we'd just tried password
4475 * authentication, we should break out of this
4476 * whole loop so as to go back to the username
4479 if (s
->type
== AUTH_TYPE_NONE
) {
4481 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4482 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4483 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4484 c_write_str(ssh
, "Server refused our key\r\n");
4485 logevent("Server refused public key");
4486 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4487 /* server declined keyboard-interactive; ignore */
4489 c_write_str(ssh
, "Access denied\r\n");
4490 logevent("Access denied");
4491 if (s
->type
== AUTH_TYPE_PASSWORD
) {
4492 s
->we_are_in
= FALSE
;
4497 c_write_str(ssh
, "Further authentication required\r\n");
4498 logevent("Further authentication required");
4502 in_commasep_string("publickey", methods
, methlen
);
4504 in_commasep_string("password", methods
, methlen
);
4505 s
->can_keyb_inter
= cfg
.try_ki_auth
&&
4506 in_commasep_string("keyboard-interactive", methods
, methlen
);
4510 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4513 * Most password/passphrase prompts will be
4514 * non-echoing, so we set this to 0 by default.
4515 * Exception is that some keyboard-interactive prompts
4516 * can be echoing, in which case we'll set this to 1.
4520 if (!s
->method
&& s
->can_pubkey
&&
4521 agent_exists() && !s
->tried_agent
) {
4523 * Attempt public-key authentication using Pageant.
4528 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4529 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4531 s
->tried_agent
= TRUE
;
4533 logevent("Pageant is running. Requesting keys.");
4535 /* Request the keys held by the agent. */
4536 PUT_32BIT(s
->request
, 1);
4537 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4538 agent_query(s
->request
, 5, &r
, &s
->responselen
);
4539 s
->response
= (unsigned char *) r
;
4540 if (s
->response
&& s
->responselen
>= 5 &&
4541 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4542 s
->p
= s
->response
+ 5;
4543 s
->nkeys
= GET_32BIT(s
->p
);
4547 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
4550 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
4555 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
4558 s
->pklen
= GET_32BIT(s
->p
);
4560 if (s
->publickey_blob
&&
4561 s
->pklen
== s
->publickey_bloblen
&&
4562 !memcmp(s
->p
, s
->publickey_blob
,
4563 s
->publickey_bloblen
)) {
4564 logevent("This key matches configured key file");
4565 s
->tried_pubkey_config
= 1;
4569 s
->alglen
= GET_32BIT(s
->pkblob
);
4570 s
->alg
= s
->pkblob
+ 4;
4571 s
->commentlen
= GET_32BIT(s
->p
);
4574 s
->p
+= s
->commentlen
;
4575 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4576 ssh2_pkt_addstring(ssh
, s
->username
);
4577 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4578 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4579 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
4580 ssh2_pkt_addstring_start(ssh
);
4581 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4582 ssh2_pkt_addstring_start(ssh
);
4583 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4586 crWaitUntilV(ispkt
);
4587 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4588 logevent("Key refused");
4592 if (flags
& FLAG_VERBOSE
) {
4593 c_write_str(ssh
, "Authenticating with "
4595 c_write(ssh
, s
->commentp
, s
->commentlen
);
4596 c_write_str(ssh
, "\" from agent\r\n");
4600 * Server is willing to accept the key.
4601 * Construct a SIGN_REQUEST.
4603 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4604 ssh2_pkt_addstring(ssh
, s
->username
);
4605 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4606 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4607 ssh2_pkt_addbool(ssh
, TRUE
);
4608 ssh2_pkt_addstring_start(ssh
);
4609 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4610 ssh2_pkt_addstring_start(ssh
);
4611 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4613 s
->siglen
= ssh
->pktout
.length
- 5 + 4 + 20;
4614 s
->len
= 1; /* message type */
4615 s
->len
+= 4 + s
->pklen
; /* key blob */
4616 s
->len
+= 4 + s
->siglen
; /* data to sign */
4617 s
->len
+= 4; /* flags */
4618 s
->agentreq
= smalloc(4 + s
->len
);
4619 PUT_32BIT(s
->agentreq
, s
->len
);
4620 s
->q
= s
->agentreq
+ 4;
4621 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4622 PUT_32BIT(s
->q
, s
->pklen
);
4624 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
4626 PUT_32BIT(s
->q
, s
->siglen
);
4628 /* Now the data to be signed... */
4629 PUT_32BIT(s
->q
, 20);
4631 memcpy(s
->q
, ssh
->v2_session_id
, 20);
4633 memcpy(s
->q
, ssh
->pktout
.data
+ 5,
4634 ssh
->pktout
.length
- 5);
4635 s
->q
+= ssh
->pktout
.length
- 5;
4636 /* And finally the (zero) flags word. */
4638 agent_query(s
->agentreq
, s
->len
+ 4, &vret
, &s
->retlen
);
4642 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4643 logevent("Sending Pageant's response");
4644 ssh2_add_sigblob(ssh
, s
->pkblob
, s
->pklen
,
4646 GET_32BIT(s
->ret
+ 5));
4652 ("Pageant failed to answer challenge");
4662 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
4663 && !s
->tried_pubkey_config
) {
4664 unsigned char *pub_blob
;
4665 char *algorithm
, *comment
;
4668 s
->tried_pubkey_config
= TRUE
;
4670 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4671 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4674 * Try the public key supplied in the configuration.
4676 * First, offer the public blob to see if the server is
4677 * willing to accept it.
4679 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
4682 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4683 ssh2_pkt_addstring(ssh
, s
->username
);
4684 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4685 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4686 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
4687 ssh2_pkt_addstring(ssh
, algorithm
);
4688 ssh2_pkt_addstring_start(ssh
);
4689 ssh2_pkt_addstring_data(ssh
, pub_blob
, pub_blob_len
);
4691 logevent("Offered public key"); /* FIXME */
4693 crWaitUntilV(ispkt
);
4694 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4696 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4697 continue; /* key refused; give up on it */
4700 logevent("Offer of public key accepted");
4702 * Actually attempt a serious authentication using
4705 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
4706 sprintf(s
->pwprompt
,
4707 "Passphrase for key \"%.100s\": ",
4713 c_write_str(ssh
, "Authenticating with public key \"");
4714 c_write_str(ssh
, comment
);
4715 c_write_str(ssh
, "\"\r\n");
4716 s
->method
= AUTH_PUBLICKEY_FILE
;
4720 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
4721 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
4722 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4723 s
->tried_keyb_inter
= TRUE
;
4725 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4726 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4728 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4729 ssh2_pkt_addstring(ssh
, s
->username
);
4730 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4731 ssh2_pkt_addstring(ssh
, "keyboard-interactive"); /* method */
4732 ssh2_pkt_addstring(ssh
, ""); /* lang */
4733 ssh2_pkt_addstring(ssh
, "");
4736 crWaitUntilV(ispkt
);
4737 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4738 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4740 logevent("Keyboard-interactive authentication refused");
4741 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4745 s
->kbd_inter_running
= TRUE
;
4749 if (s
->kbd_inter_running
) {
4750 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
4751 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4752 s
->tried_keyb_inter
= TRUE
;
4754 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4755 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4757 if (s
->curr_prompt
== 0) {
4759 * We've got a fresh USERAUTH_INFO_REQUEST.
4760 * Display header data, and start going through
4763 char *name
, *inst
, *lang
;
4764 int name_len
, inst_len
, lang_len
;
4766 ssh2_pkt_getstring(ssh
, &name
, &name_len
);
4767 ssh2_pkt_getstring(ssh
, &inst
, &inst_len
);
4768 ssh2_pkt_getstring(ssh
, &lang
, &lang_len
);
4770 c_write_untrusted(ssh
, name
, name_len
);
4771 c_write_str(ssh
, "\r\n");
4774 c_write_untrusted(ssh
, inst
, inst_len
);
4775 c_write_str(ssh
, "\r\n");
4777 s
->num_prompts
= ssh2_pkt_getuint32(ssh
);
4781 * If there are prompts remaining in the packet,
4782 * display one and get a response.
4784 if (s
->curr_prompt
< s
->num_prompts
) {
4788 ssh2_pkt_getstring(ssh
, &prompt
, &prompt_len
);
4789 if (prompt_len
> 0) {
4790 strncpy(s
->pwprompt
, prompt
, sizeof(s
->pwprompt
));
4791 s
->pwprompt
[prompt_len
< sizeof(s
->pwprompt
) ?
4792 prompt_len
: sizeof(s
->pwprompt
)-1] = '\0';
4795 "<server failed to send prompt>: ");
4797 s
->echo
= ssh2_pkt_getbool(ssh
);
4803 if (!s
->method
&& s
->can_passwd
) {
4804 s
->method
= AUTH_PASSWORD
;
4805 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4806 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4807 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
4814 if (!ssh_get_line(s
->pwprompt
, s
->password
,
4815 sizeof(s
->password
), TRUE
)) {
4817 * get_line failed to get a password (for
4818 * example because one was supplied on the
4819 * command line which has already failed to
4822 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
4823 ssh2_pkt_adduint32(ssh
,SSH2_DISCONNECT_BY_APPLICATION
);
4824 ssh2_pkt_addstring(ssh
, "No more passwords available"
4826 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
4828 logevent("Unable to authenticate");
4829 connection_fatal("Unable to authenticate");
4830 ssh
->state
= SSH_STATE_CLOSED
;
4834 int ret
; /* need not be saved across crReturn */
4835 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
4838 setup_userpass_input(ssh
, s
->password
,
4839 sizeof(s
->password
), s
->echo
);
4841 crWaitUntilV(!ispkt
);
4842 ret
= process_userpass_input(ssh
, in
, inlen
);
4846 c_write_str(ssh
, "\r\n");
4850 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
4852 * We have our passphrase. Now try the actual authentication.
4854 struct ssh2_userkey
*key
;
4856 key
= ssh2_load_userkey(cfg
.keyfile
, s
->password
);
4857 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4858 if (key
== SSH2_WRONG_PASSPHRASE
) {
4859 c_write_str(ssh
, "Wrong passphrase\r\n");
4860 s
->tried_pubkey_config
= FALSE
;
4862 c_write_str(ssh
, "Unable to load private key\r\n");
4863 s
->tried_pubkey_config
= TRUE
;
4865 /* Send a spurious AUTH_NONE to return to the top. */
4866 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4867 ssh2_pkt_addstring(ssh
, s
->username
);
4868 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4869 ssh2_pkt_addstring(ssh
, "none"); /* method */
4871 s
->type
= AUTH_TYPE_NONE
;
4873 unsigned char *pkblob
, *sigblob
, *sigdata
;
4874 int pkblob_len
, sigblob_len
, sigdata_len
;
4877 * We have loaded the private key and the server
4878 * has announced that it's willing to accept it.
4879 * Hallelujah. Generate a signature and send it.
4881 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4882 ssh2_pkt_addstring(ssh
, s
->username
);
4883 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4884 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4885 ssh2_pkt_addbool(ssh
, TRUE
);
4886 ssh2_pkt_addstring(ssh
, key
->alg
->name
);
4887 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4888 ssh2_pkt_addstring_start(ssh
);
4889 ssh2_pkt_addstring_data(ssh
, pkblob
, pkblob_len
);
4892 * The data to be signed is:
4896 * followed by everything so far placed in the
4899 sigdata_len
= ssh
->pktout
.length
- 5 + 4 + 20;
4900 sigdata
= smalloc(sigdata_len
);
4901 PUT_32BIT(sigdata
, 20);
4902 memcpy(sigdata
+ 4, ssh
->v2_session_id
, 20);
4903 memcpy(sigdata
+ 24, ssh
->pktout
.data
+ 5,
4904 ssh
->pktout
.length
- 5);
4905 sigblob
= key
->alg
->sign(key
->data
, sigdata
,
4906 sigdata_len
, &sigblob_len
);
4907 ssh2_add_sigblob(ssh
, pkblob
, pkblob_len
,
4908 sigblob
, sigblob_len
);
4914 s
->type
= AUTH_TYPE_PUBLICKEY
;
4916 } else if (s
->method
== AUTH_PASSWORD
) {
4918 * We send the password packet lumped tightly together with
4919 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4920 * string long enough to make the total length of the two
4921 * packets constant. This should ensure that a passive
4922 * listener doing traffic analyis can't work out the length
4925 * For this to work, we need an assumption about the
4926 * maximum length of the password packet. I think 256 is
4927 * pretty conservative. Anyone using a password longer than
4928 * that probably doesn't have much to worry about from
4929 * people who find out how long their password is!
4931 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4932 ssh2_pkt_addstring(ssh
, s
->username
);
4933 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4934 ssh2_pkt_addstring(ssh
, "password");
4935 ssh2_pkt_addbool(ssh
, FALSE
);
4936 ssh2_pkt_addstring(ssh
, s
->password
);
4937 ssh2_pkt_defer(ssh
);
4939 * We'll include a string that's an exact multiple of the
4940 * cipher block size. If the cipher is NULL for some
4941 * reason, we don't do this trick at all because we gain
4944 if (ssh
->cscipher
) {
4947 stringlen
= (256 - ssh
->deferred_len
);
4948 stringlen
+= ssh
->cscipher
->blksize
- 1;
4949 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
4952 * Temporarily disable actual compression,
4953 * so we can guarantee to get this string
4954 * exactly the length we want it. The
4955 * compression-disabling routine should
4956 * return an integer indicating how many
4957 * bytes we should adjust our string length
4961 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
4963 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
4964 ssh2_pkt_addstring_start(ssh
);
4965 for (i
= 0; i
< stringlen
; i
++) {
4966 char c
= (char) random_byte();
4967 ssh2_pkt_addstring_data(ssh
, &c
, 1);
4969 ssh2_pkt_defer(ssh
);
4971 ssh_pkt_defersend(ssh
);
4972 logevent("Sent password");
4973 s
->type
= AUTH_TYPE_PASSWORD
;
4974 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
4975 if (s
->curr_prompt
== 0) {
4976 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_INFO_RESPONSE
);
4977 ssh2_pkt_adduint32(ssh
, s
->num_prompts
);
4979 if (s
->need_pw
) { /* only add pw if we just got one! */
4980 ssh2_pkt_addstring(ssh
, s
->password
);
4981 memset(s
->password
, 0, sizeof(s
->password
));
4984 if (s
->curr_prompt
>= s
->num_prompts
) {
4988 * If there are prompts remaining, we set
4989 * `gotit' so that we won't attempt to get
4990 * another packet. Then we go back round the
4991 * loop and will end up retrieving another
4992 * prompt out of the existing packet. Funky or
4997 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4999 c_write_str(ssh
, "No supported authentication methods"
5000 " left to try!\r\n");
5001 logevent("No supported authentications offered."
5003 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5004 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5005 ssh2_pkt_addstring(ssh
, "No supported authentication"
5006 " methods available");
5007 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5009 ssh
->state
= SSH_STATE_CLOSED
;
5013 } while (!s
->we_are_in
);
5016 * Now we're authenticated for the connection protocol. The
5017 * connection protocol will automatically have started at this
5018 * point; there's no need to send SERVICE_REQUEST.
5022 * So now create a channel with a session in it.
5024 ssh
->channels
= newtree234(ssh_channelcmp
);
5025 ssh
->mainchan
= smalloc(sizeof(struct ssh_channel
));
5026 ssh
->mainchan
->ssh
= ssh
;
5027 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
5028 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
5029 ssh2_pkt_addstring(ssh
, "session");
5030 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->localid
);
5031 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5032 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
5033 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5035 crWaitUntilV(ispkt
);
5036 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5037 bombout(("Server refused to open a session"));
5039 /* FIXME: error data comes back in FAILURE packet */
5041 if (ssh2_pkt_getuint32(ssh
) != ssh
->mainchan
->localid
) {
5042 bombout(("Server's channel confirmation cited wrong channel"));
5045 ssh
->mainchan
->remoteid
= ssh2_pkt_getuint32(ssh
);
5046 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
5047 ssh
->mainchan
->closes
= 0;
5048 ssh
->mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32(ssh
);
5049 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32(ssh
);
5050 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
5051 add234(ssh
->channels
, ssh
->mainchan
);
5052 logevent("Opened channel for session");
5055 * Potentially enable X11 forwarding.
5057 if (cfg
.x11_forward
) {
5058 char proto
[20], data
[64];
5059 logevent("Requesting X11 forwarding");
5060 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
5061 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5062 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5063 ssh2_pkt_addstring(ssh
, "x11-req");
5064 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5065 ssh2_pkt_addbool(ssh
, 0); /* many connections */
5066 ssh2_pkt_addstring(ssh
, proto
);
5067 ssh2_pkt_addstring(ssh
, data
);
5068 ssh2_pkt_adduint32(ssh
, 0); /* screen number */
5072 crWaitUntilV(ispkt
);
5073 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5074 unsigned i
= ssh2_pkt_getuint32(ssh
);
5075 struct ssh_channel
*c
;
5076 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5078 continue; /* nonexistent channel */
5079 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5081 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5083 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5084 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5085 bombout(("Unexpected response to X11 forwarding request:"
5086 " packet type %d", ssh
->pktin
.type
));
5089 logevent("X11 forwarding refused");
5091 logevent("X11 forwarding enabled");
5092 ssh
->X11_fwd_enabled
= TRUE
;
5097 * Enable port forwardings.
5102 int sport
,dport
,sserv
,dserv
;
5103 char sports
[256], dports
[256], host
[256];
5107 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
5108 /* Add port forwardings. */
5109 ssh
->portfwd_strptr
= cfg
.portfwd
;
5110 while (*ssh
->portfwd_strptr
) {
5111 type
= *ssh
->portfwd_strptr
++;
5113 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t')
5114 sports
[n
++] = *ssh
->portfwd_strptr
++;
5116 if (*ssh
->portfwd_strptr
== '\t')
5117 ssh
->portfwd_strptr
++;
5119 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':')
5120 host
[n
++] = *ssh
->portfwd_strptr
++;
5122 if (*ssh
->portfwd_strptr
== ':')
5123 ssh
->portfwd_strptr
++;
5125 while (*ssh
->portfwd_strptr
)
5126 dports
[n
++] = *ssh
->portfwd_strptr
++;
5128 ssh
->portfwd_strptr
++;
5129 dport
= atoi(dports
);
5133 se
= getservbyname(dports
, NULL
);
5135 dport
= ntohs(se
->s_port
);
5138 "Service lookup failed for destination port \"%s\"",
5143 sport
= atoi(sports
);
5147 se
= getservbyname(sports
, NULL
);
5149 sport
= ntohs(se
->s_port
);
5152 "Service lookup failed for source port \"%s\"",
5157 if (sport
&& dport
) {
5159 pfd_addforward(host
, dport
, sport
, ssh
);
5160 sprintf(buf
, "Local port %.*s%.*s%d%.*s forwarding to"
5161 " %s:%.*s%.*s%d%.*s",
5162 sserv ?
strlen(sports
) : 0, sports
,
5163 sserv
, "(", sport
, sserv
, ")",
5165 dserv ?
strlen(dports
) : 0, dports
,
5166 dserv
, "(", dport
, dserv
, ")");
5169 struct ssh_rportfwd
*pf
;
5170 pf
= smalloc(sizeof(*pf
));
5171 strcpy(pf
->dhost
, host
);
5174 if (add234(ssh
->rportfwds
, pf
) != pf
) {
5176 "Duplicate remote port forwarding to %s:%d",
5181 sprintf(buf
, "Requesting remote port %.*s%.*s%d%.*s"
5182 " forward to %s:%.*s%.*s%d%.*s",
5183 sserv ?
strlen(sports
) : 0, sports
,
5184 sserv
, "(", sport
, sserv
, ")",
5186 dserv ?
strlen(dports
) : 0, dports
,
5187 dserv
, "(", dport
, dserv
, ")");
5189 ssh2_pkt_init(ssh
, SSH2_MSG_GLOBAL_REQUEST
);
5190 ssh2_pkt_addstring(ssh
, "tcpip-forward");
5191 ssh2_pkt_addbool(ssh
, 1);/* want reply */
5192 if (cfg
.rport_acceptall
)
5193 ssh2_pkt_addstring(ssh
, "0.0.0.0");
5195 ssh2_pkt_addstring(ssh
, "127.0.0.1");
5196 ssh2_pkt_adduint32(ssh
, sport
);
5200 crWaitUntilV(ispkt
);
5201 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5202 unsigned i
= ssh2_pkt_getuint32(ssh
);
5203 struct ssh_channel
*c
;
5204 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5206 continue;/* nonexistent channel */
5207 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5209 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5211 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5212 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5213 bombout(("Unexpected response to port "
5214 "forwarding request: packet type %d",
5218 logevent("Server refused this port forwarding");
5220 logevent("Remote port forwarding enabled");
5229 * Potentially enable agent forwarding.
5231 if (cfg
.agentfwd
&& agent_exists()) {
5232 logevent("Requesting OpenSSH-style agent forwarding");
5233 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5234 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5235 ssh2_pkt_addstring(ssh
, "auth-agent-req@openssh.com");
5236 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5240 crWaitUntilV(ispkt
);
5241 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5242 unsigned i
= ssh2_pkt_getuint32(ssh
);
5243 struct ssh_channel
*c
;
5244 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5246 continue; /* nonexistent channel */
5247 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5249 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5251 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5252 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5253 bombout(("Unexpected response to agent forwarding request:"
5254 " packet type %d", ssh
->pktin
.type
));
5257 logevent("Agent forwarding refused");
5259 logevent("Agent forwarding enabled");
5260 ssh
->agentfwd_enabled
= TRUE
;
5265 * Now allocate a pty for the session.
5268 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5269 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5270 ssh2_pkt_addstring(ssh
, "pty-req");
5271 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5272 ssh2_pkt_addstring(ssh
, cfg
.termtype
);
5273 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5274 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5275 ssh2_pkt_adduint32(ssh
, 0); /* pixel width */
5276 ssh2_pkt_adduint32(ssh
, 0); /* pixel height */
5277 ssh2_pkt_addstring_start(ssh
);
5278 ssh2_pkt_addstring_data(ssh
, "\0", 1); /* TTY_OP_END, no special options */
5280 ssh
->state
= SSH_STATE_INTERMED
;
5283 crWaitUntilV(ispkt
);
5284 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5285 unsigned i
= ssh2_pkt_getuint32(ssh
);
5286 struct ssh_channel
*c
;
5287 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5289 continue; /* nonexistent channel */
5290 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5292 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5294 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5295 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5296 bombout(("Unexpected response to pty request:"
5297 " packet type %d", ssh
->pktin
.type
));
5300 c_write_str(ssh
, "Server refused to allocate pty\r\n");
5301 ssh
->editing
= ssh
->echoing
= 1;
5303 logevent("Allocated pty");
5306 ssh
->editing
= ssh
->echoing
= 1;
5310 * Start a shell or a remote command. We may have to attempt
5311 * this twice if the config data has provided a second choice
5318 if (ssh
->fallback_cmd
) {
5319 subsys
= cfg
.ssh_subsys2
;
5320 cmd
= cfg
.remote_cmd_ptr2
;
5322 subsys
= cfg
.ssh_subsys
;
5323 cmd
= cfg
.remote_cmd_ptr
;
5326 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5327 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5329 ssh2_pkt_addstring(ssh
, "subsystem");
5330 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5331 ssh2_pkt_addstring(ssh
, cmd
);
5333 ssh2_pkt_addstring(ssh
, "exec");
5334 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5335 ssh2_pkt_addstring(ssh
, cmd
);
5337 ssh2_pkt_addstring(ssh
, "shell");
5338 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5342 crWaitUntilV(ispkt
);
5343 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5344 unsigned i
= ssh2_pkt_getuint32(ssh
);
5345 struct ssh_channel
*c
;
5346 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5348 continue; /* nonexistent channel */
5349 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5351 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5352 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5353 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5354 bombout(("Unexpected response to shell/command request:"
5355 " packet type %d", ssh
->pktin
.type
));
5359 * We failed to start the command. If this is the
5360 * fallback command, we really are finished; if it's
5361 * not, and if the fallback command exists, try falling
5362 * back to it before complaining.
5364 if (!ssh
->fallback_cmd
&& cfg
.remote_cmd_ptr2
!= NULL
) {
5365 logevent("Primary command failed; attempting fallback");
5366 ssh
->fallback_cmd
= TRUE
;
5369 bombout(("Server refused to start a shell/command"));
5372 logevent("Started a shell/command");
5377 ssh
->state
= SSH_STATE_SESSION
;
5378 if (ssh
->size_needed
)
5379 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
5380 if (ssh
->eof_needed
)
5381 ssh_special(ssh
, TS_EOF
);
5387 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
5391 s
->try_send
= FALSE
;
5393 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5394 ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5397 unsigned i
= ssh2_pkt_getuint32(ssh
);
5398 struct ssh_channel
*c
;
5399 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5401 continue; /* nonexistent channel */
5402 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5403 ssh2_pkt_getuint32(ssh
) != SSH2_EXTENDED_DATA_STDERR
)
5404 continue; /* extended but not stderr */
5405 ssh2_pkt_getstring(ssh
, &data
, &length
);
5408 c
->v
.v2
.locwindow
-= length
;
5410 case CHAN_MAINSESSION
:
5412 from_backend(ssh
->frontend
, ssh
->pktin
.type
==
5413 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5417 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5420 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5423 while (length
> 0) {
5424 if (c
->u
.a
.lensofar
< 4) {
5425 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5426 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5430 c
->u
.a
.lensofar
+= l
;
5432 if (c
->u
.a
.lensofar
== 4) {
5434 4 + GET_32BIT(c
->u
.a
.msglen
);
5435 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5436 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5438 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5440 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5442 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5446 c
->u
.a
.lensofar
+= l
;
5448 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5449 void *reply
, *sentreply
;
5451 agent_query(c
->u
.a
.message
,
5452 c
->u
.a
.totallen
, &reply
,
5457 /* Fake SSH_AGENT_FAILURE. */
5458 sentreply
= "\0\0\0\1\5";
5461 ssh2_add_channel_data(c
, sentreply
, replylen
);
5465 sfree(c
->u
.a
.message
);
5466 c
->u
.a
.lensofar
= 0;
5473 * If we are not buffering too much data,
5474 * enlarge the window again at the remote side.
5476 if (bufsize
< OUR_V2_WINSIZE
)
5477 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5479 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5480 unsigned i
= ssh2_pkt_getuint32(ssh
);
5481 struct ssh_channel
*c
;
5483 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5485 continue; /* nonexistent channel */
5487 if (c
->type
== CHAN_X11
) {
5489 * Remote EOF on an X11 channel means we should
5490 * wrap up and close the channel ourselves.
5492 x11_close(c
->u
.x11
.s
);
5494 } else if (c
->type
== CHAN_AGENT
) {
5496 } else if (c
->type
== CHAN_SOCKDATA
) {
5497 pfd_close(c
->u
.pfd
.s
);
5500 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5501 unsigned i
= ssh2_pkt_getuint32(ssh
);
5502 struct ssh_channel
*c
;
5504 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5505 if (!c
|| ((int)c
->remoteid
) == -1) {
5506 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5507 c ?
"half-open" : "nonexistent", i
));
5509 /* Do pre-close processing on the channel. */
5511 case CHAN_MAINSESSION
:
5512 break; /* nothing to see here, move along */
5514 if (c
->u
.x11
.s
!= NULL
)
5515 x11_close(c
->u
.x11
.s
);
5522 if (c
->u
.pfd
.s
!= NULL
)
5523 pfd_close(c
->u
.pfd
.s
);
5527 if (c
->closes
== 0) {
5528 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
5529 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5532 del234(ssh
->channels
, c
);
5533 bufchain_clear(&c
->v
.v2
.outbuffer
);
5537 * See if that was the last channel left open.
5539 if (count234(ssh
->channels
) == 0) {
5542 * We used to send SSH_MSG_DISCONNECT here,
5543 * because I'd believed that _every_ conforming
5544 * SSH2 connection had to end with a disconnect
5545 * being sent by at least one side; apparently
5546 * I was wrong and it's perfectly OK to
5547 * unceremoniously slam the connection shut
5548 * when you're done, and indeed OpenSSH feels
5549 * this is more polite than sending a
5550 * DISCONNECT. So now we don't.
5552 logevent("All channels closed. Disconnecting");
5553 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5554 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5555 ssh2_pkt_addstring(ssh
, "All open channels closed");
5556 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5559 ssh
->state
= SSH_STATE_CLOSED
;
5562 continue; /* remote sends close; ignore (FIXME) */
5563 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5564 unsigned i
= ssh2_pkt_getuint32(ssh
);
5565 struct ssh_channel
*c
;
5566 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5568 continue; /* nonexistent channel */
5569 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5571 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5572 unsigned i
= ssh2_pkt_getuint32(ssh
);
5573 struct ssh_channel
*c
;
5574 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5576 continue; /* nonexistent channel */
5577 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5578 continue; /* dunno why they're confirming this */
5579 c
->remoteid
= ssh2_pkt_getuint32(ssh
);
5580 c
->type
= CHAN_SOCKDATA
;
5581 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32(ssh
);
5582 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32(ssh
);
5584 pfd_confirm(c
->u
.pfd
.s
);
5587 * We have a pending close on this channel,
5588 * which we decided on before the server acked
5589 * the channel open. So now we know the
5590 * remoteid, we can close it again.
5592 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
5593 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5596 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5597 unsigned i
= ssh2_pkt_getuint32(ssh
);
5598 struct ssh_channel
*c
;
5599 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5601 continue; /* nonexistent channel */
5602 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5603 continue; /* dunno why they're failing this */
5605 logevent("Forwarded connection refused by server");
5607 pfd_close(c
->u
.pfd
.s
);
5609 del234(ssh
->channels
, c
);
5611 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5614 int typelen
, want_reply
;
5615 struct ssh_channel
*c
;
5617 localid
= ssh2_pkt_getuint32(ssh
);
5618 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5619 want_reply
= ssh2_pkt_getbool(ssh
);
5622 * First, check that the channel exists. Otherwise,
5623 * we can instantly disconnect with a rude message.
5625 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5628 sprintf(buf
, "Received channel request for nonexistent"
5629 " channel %d", localid
);
5631 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5632 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5633 ssh2_pkt_addstring(ssh
, buf
);
5634 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5636 connection_fatal("%s", buf
);
5637 ssh
->state
= SSH_STATE_CLOSED
;
5642 * Having got the channel number, we now look at
5643 * the request type string to see if it's something
5646 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5647 c
== ssh
->mainchan
) {
5648 /* We recognise "exit-status" on the primary channel. */
5650 ssh
->exitcode
= ssh2_pkt_getuint32(ssh
);
5651 sprintf(buf
, "Server sent command exit status %d",
5655 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_SUCCESS
);
5656 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5661 * This is a channel request we don't know
5662 * about, so we now either ignore the request
5663 * or respond with CHANNEL_FAILURE, depending
5667 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_FAILURE
);
5668 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5672 } else if (ssh
->pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5674 int typelen
, want_reply
;
5676 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5677 want_reply
= ssh2_pkt_getbool(ssh
);
5680 * We currently don't support any global requests
5681 * at all, so we either ignore the request or
5682 * respond with REQUEST_FAILURE, depending on
5686 ssh2_pkt_init(ssh
, SSH2_MSG_REQUEST_FAILURE
);
5689 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5693 struct ssh_channel
*c
;
5694 unsigned remid
, winsize
, pktsize
;
5695 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5696 c
= smalloc(sizeof(struct ssh_channel
));
5699 remid
= ssh2_pkt_getuint32(ssh
);
5700 winsize
= ssh2_pkt_getuint32(ssh
);
5701 pktsize
= ssh2_pkt_getuint32(ssh
);
5703 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5704 if (!ssh
->X11_fwd_enabled
)
5705 error
= "X11 forwarding is not enabled";
5706 else if (x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) !=
5708 error
= "Unable to open an X11 connection";
5712 } else if (typelen
== 15 &&
5713 !memcmp(type
, "forwarded-tcpip", 15)) {
5714 struct ssh_rportfwd pf
, *realpf
;
5717 ssh2_pkt_getstring(ssh
, &dummy
, &dummylen
);/* skip address */
5718 pf
.sport
= ssh2_pkt_getuint32(ssh
);
5719 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5720 if (realpf
== NULL
) {
5721 error
= "Remote port is not recognised";
5723 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5726 sprintf(buf
, "Received remote port open request for %s:%d",
5727 realpf
->dhost
, realpf
->dport
);
5730 sprintf(buf
, "Port open failed: %s", e
);
5732 error
= "Port open failed";
5734 logevent("Forwarded port opened successfully");
5735 c
->type
= CHAN_SOCKDATA
;
5738 } else if (typelen
== 22 &&
5739 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5740 if (!ssh
->agentfwd_enabled
)
5741 error
= "Agent forwarding is not enabled";
5743 c
->type
= CHAN_AGENT
; /* identify channel type */
5744 c
->u
.a
.lensofar
= 0;
5747 error
= "Unsupported channel type requested";
5750 c
->remoteid
= remid
;
5752 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5753 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5754 ssh2_pkt_adduint32(ssh
, SSH2_OPEN_CONNECT_FAILED
);
5755 ssh2_pkt_addstring(ssh
, error
);
5756 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5760 c
->localid
= alloc_channel_id(ssh
);
5762 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5763 c
->v
.v2
.remwindow
= winsize
;
5764 c
->v
.v2
.remmaxpkt
= pktsize
;
5765 bufchain_init(&c
->v
.v2
.outbuffer
);
5766 add234(ssh
->channels
, c
);
5767 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5768 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5769 ssh2_pkt_adduint32(ssh
, c
->localid
);
5770 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);
5771 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5775 bombout(("Strange packet received: type %d", ssh
->pktin
.type
));
5780 * We have spare data. Add it to the channel buffer.
5782 ssh2_add_channel_data(ssh
->mainchan
, in
, inlen
);
5787 struct ssh_channel
*c
;
5789 * Try to send data on all channels if we can.
5791 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
5792 int bufsize
= ssh2_try_send(c
);
5795 case CHAN_MAINSESSION
:
5796 /* stdin need not receive an unthrottle
5797 * notification since it will be polled */
5800 x11_unthrottle(c
->u
.x11
.s
);
5803 /* agent sockets are request/response and need no
5804 * buffer management */
5807 pfd_unthrottle(c
->u
.pfd
.s
);
5819 * Handle the top-level SSH2 protocol.
5821 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
5823 if (do_ssh2_transport(ssh
, in
, inlen
, ispkt
) == 0)
5825 do_ssh2_authconn(ssh
, in
, inlen
, ispkt
);
5829 * Called to set up the connection.
5831 * Returns an error message, or NULL on success.
5833 static char *ssh_init(void *frontend_handle
, void **backend_handle
,
5834 char *host
, int port
, char **realhost
, int nodelay
)
5839 ssh
= smalloc(sizeof(*ssh
));
5842 ssh
->v1_cipher_ctx
= NULL
;
5843 ssh
->crcda_ctx
= NULL
;
5844 ssh
->cscipher
= NULL
;
5845 ssh
->cs_cipher_ctx
= NULL
;
5846 ssh
->sccipher
= NULL
;
5847 ssh
->sc_cipher_ctx
= NULL
;
5849 ssh
->sc_mac_ctx
= NULL
;
5851 ssh
->sc_mac_ctx
= NULL
;
5853 ssh
->cs_comp_ctx
= NULL
;
5855 ssh
->sc_comp_ctx
= NULL
;
5857 ssh
->hostkey
= NULL
;
5859 ssh
->state
= SSH_STATE_PREPACKET
;
5860 ssh
->size_needed
= FALSE
;
5861 ssh
->eof_needed
= FALSE
;
5864 static const struct Packet empty
= { 0, 0, NULL
, NULL
, 0 };
5865 ssh
->pktin
= ssh
->pktout
= empty
;
5867 ssh
->deferred_send_data
= NULL
;
5868 ssh
->deferred_len
= 0;
5869 ssh
->deferred_size
= 0;
5870 ssh
->fallback_cmd
= 0;
5872 ssh
->v2_outgoing_sequence
= 0;
5873 ssh
->ssh1_rdpkt_crstate
= 0;
5874 ssh
->ssh2_rdpkt_crstate
= 0;
5875 ssh
->do_ssh_init_crstate
= 0;
5876 ssh
->ssh_gotdata_crstate
= 0;
5877 ssh
->ssh1_protocol_crstate
= 0;
5878 ssh
->do_ssh1_login_crstate
= 0;
5879 ssh
->do_ssh2_transport_crstate
= 0;
5880 ssh
->do_ssh2_authconn_crstate
= 0;
5881 ssh
->do_ssh_init_state
= NULL
;
5882 ssh
->do_ssh1_login_state
= NULL
;
5883 ssh
->do_ssh2_transport_state
= NULL
;
5884 ssh
->do_ssh2_authconn_state
= NULL
;
5886 *backend_handle
= ssh
;
5889 if (crypto_startup() == 0)
5890 return "Microsoft high encryption pack not installed!";
5893 ssh
->frontend
= frontend_handle
;
5894 ssh
->term_width
= cfg
.width
;
5895 ssh
->term_height
= cfg
.height
;
5900 ssh
->v1_throttle_count
= 0;
5901 ssh
->overall_bufsize
= 0;
5902 ssh
->fallback_cmd
= 0;
5904 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
);
5912 * Called to send data down the Telnet connection.
5914 static int ssh_send(void *handle
, char *buf
, int len
)
5916 Ssh ssh
= (Ssh
) handle
;
5918 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
5921 ssh
->protocol(ssh
, buf
, len
, 0);
5923 return ssh_sendbuffer(ssh
);
5927 * Called to query the current amount of buffered stdin data.
5929 static int ssh_sendbuffer(void *handle
)
5931 Ssh ssh
= (Ssh
) handle
;
5934 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
5938 * If the SSH socket itself has backed up, add the total backup
5939 * size on that to any individual buffer on the stdin channel.
5942 if (ssh
->throttled_all
)
5943 override_value
= ssh
->overall_bufsize
;
5945 if (ssh
->version
== 1) {
5946 return override_value
;
5947 } else if (ssh
->version
== 2) {
5948 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
5949 return override_value
;
5951 return (override_value
+
5952 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
5959 * Called to set the size of the window from SSH's POV.
5961 static void ssh_size(void *handle
, int width
, int height
)
5963 Ssh ssh
= (Ssh
) handle
;
5965 ssh
->term_width
= width
;
5966 ssh
->term_height
= height
;
5968 switch (ssh
->state
) {
5969 case SSH_STATE_BEFORE_SIZE
:
5970 case SSH_STATE_PREPACKET
:
5971 case SSH_STATE_CLOSED
:
5972 break; /* do nothing */
5973 case SSH_STATE_INTERMED
:
5974 ssh
->size_needed
= TRUE
; /* buffer for later */
5976 case SSH_STATE_SESSION
:
5980 if (ssh
->version
== 1) {
5981 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
5982 PKT_INT
, ssh
->term_height
,
5983 PKT_INT
, ssh
->term_width
,
5984 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
5986 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5987 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5988 ssh2_pkt_addstring(ssh
, "window-change");
5989 ssh2_pkt_addbool(ssh
, 0);
5990 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5991 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5992 ssh2_pkt_adduint32(ssh
, 0);
5993 ssh2_pkt_adduint32(ssh
, 0);
6002 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6003 * can send an EOF and collect resulting output (e.g. `plink
6006 static void ssh_special(void *handle
, Telnet_Special code
)
6008 Ssh ssh
= (Ssh
) handle
;
6010 if (code
== TS_EOF
) {
6011 if (ssh
->state
!= SSH_STATE_SESSION
) {
6013 * Buffer the EOF in case we are pre-SESSION, so we can
6014 * send it as soon as we reach SESSION.
6017 ssh
->eof_needed
= TRUE
;
6020 if (ssh
->version
== 1) {
6021 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
6023 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_EOF
);
6024 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6027 logevent("Sent EOF message");
6028 } else if (code
== TS_PING
) {
6029 if (ssh
->state
== SSH_STATE_CLOSED
6030 || ssh
->state
== SSH_STATE_PREPACKET
) return;
6031 if (ssh
->version
== 1) {
6032 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
6033 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
6035 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
6036 ssh2_pkt_addstring_start(ssh
);
6044 void *new_sock_channel(void *handle
, Socket s
)
6046 Ssh ssh
= (Ssh
) handle
;
6047 struct ssh_channel
*c
;
6048 c
= smalloc(sizeof(struct ssh_channel
));
6052 c
->remoteid
= -1; /* to be set when open confirmed */
6053 c
->localid
= alloc_channel_id(ssh
);
6055 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
6057 bufchain_init(&c
->v
.v2
.outbuffer
);
6058 add234(ssh
->channels
, c
);
6064 * This is called when stdout/stderr (the entity to which
6065 * from_backend sends data) manages to clear some backlog.
6067 void ssh_unthrottle(void *handle
, int bufsize
)
6069 Ssh ssh
= (Ssh
) handle
;
6070 if (ssh
->version
== 1) {
6071 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
6072 ssh
->v1_stdout_throttling
= 0;
6073 ssh1_throttle(ssh
, -1);
6076 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
6077 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
6081 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
6083 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
,