17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_KEX_MASK 0x000F
110 #define SSH2_PKTCTX_PUBLICKEY 0x0010
111 #define SSH2_PKTCTX_PASSWORD 0x0020
112 #define SSH2_PKTCTX_KBDINTER 0x0040
113 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
115 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
131 static const char *const ssh2_disconnect_reasons
[] = {
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
150 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
155 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
158 * Various remote-bug flags.
160 #define BUG_CHOKES_ON_SSH1_IGNORE 1
161 #define BUG_SSH2_HMAC 2
162 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
163 #define BUG_CHOKES_ON_RSA 8
164 #define BUG_SSH2_RSA_PADDING 16
165 #define BUG_SSH2_DERIVEKEY 32
166 #define BUG_SSH2_REKEY 64
167 #define BUG_SSH2_PK_SESSIONID 128
169 #define translate(x) if (type == x) return #x
170 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
171 static char *ssh1_pkt_type(int type
)
173 translate(SSH1_MSG_DISCONNECT
);
174 translate(SSH1_SMSG_PUBLIC_KEY
);
175 translate(SSH1_CMSG_SESSION_KEY
);
176 translate(SSH1_CMSG_USER
);
177 translate(SSH1_CMSG_AUTH_RSA
);
178 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
179 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
180 translate(SSH1_CMSG_AUTH_PASSWORD
);
181 translate(SSH1_CMSG_REQUEST_PTY
);
182 translate(SSH1_CMSG_WINDOW_SIZE
);
183 translate(SSH1_CMSG_EXEC_SHELL
);
184 translate(SSH1_CMSG_EXEC_CMD
);
185 translate(SSH1_SMSG_SUCCESS
);
186 translate(SSH1_SMSG_FAILURE
);
187 translate(SSH1_CMSG_STDIN_DATA
);
188 translate(SSH1_SMSG_STDOUT_DATA
);
189 translate(SSH1_SMSG_STDERR_DATA
);
190 translate(SSH1_CMSG_EOF
);
191 translate(SSH1_SMSG_EXIT_STATUS
);
192 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
193 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
194 translate(SSH1_MSG_CHANNEL_DATA
);
195 translate(SSH1_MSG_CHANNEL_CLOSE
);
196 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
197 translate(SSH1_SMSG_X11_OPEN
);
198 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
199 translate(SSH1_MSG_PORT_OPEN
);
200 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
201 translate(SSH1_SMSG_AGENT_OPEN
);
202 translate(SSH1_MSG_IGNORE
);
203 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
204 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
205 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
206 translate(SSH1_MSG_DEBUG
);
207 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
208 translate(SSH1_CMSG_AUTH_TIS
);
209 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
210 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
211 translate(SSH1_CMSG_AUTH_CCARD
);
212 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
213 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
216 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
218 translate(SSH2_MSG_DISCONNECT
);
219 translate(SSH2_MSG_IGNORE
);
220 translate(SSH2_MSG_UNIMPLEMENTED
);
221 translate(SSH2_MSG_DEBUG
);
222 translate(SSH2_MSG_SERVICE_REQUEST
);
223 translate(SSH2_MSG_SERVICE_ACCEPT
);
224 translate(SSH2_MSG_KEXINIT
);
225 translate(SSH2_MSG_NEWKEYS
);
226 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
227 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
228 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
231 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
232 translate(SSH2_MSG_USERAUTH_REQUEST
);
233 translate(SSH2_MSG_USERAUTH_FAILURE
);
234 translate(SSH2_MSG_USERAUTH_SUCCESS
);
235 translate(SSH2_MSG_USERAUTH_BANNER
);
236 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
237 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
238 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
239 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
240 translate(SSH2_MSG_GLOBAL_REQUEST
);
241 translate(SSH2_MSG_REQUEST_SUCCESS
);
242 translate(SSH2_MSG_REQUEST_FAILURE
);
243 translate(SSH2_MSG_CHANNEL_OPEN
);
244 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
245 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
246 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
247 translate(SSH2_MSG_CHANNEL_DATA
);
248 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
249 translate(SSH2_MSG_CHANNEL_EOF
);
250 translate(SSH2_MSG_CHANNEL_CLOSE
);
251 translate(SSH2_MSG_CHANNEL_REQUEST
);
252 translate(SSH2_MSG_CHANNEL_SUCCESS
);
253 translate(SSH2_MSG_CHANNEL_FAILURE
);
259 #define GET_32BIT(cp) \
260 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
261 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
262 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
263 ((unsigned long)(unsigned char)(cp)[3]))
265 #define PUT_32BIT(cp, value) { \
266 (cp)[0] = (unsigned char)((value) >> 24); \
267 (cp)[1] = (unsigned char)((value) >> 16); \
268 (cp)[2] = (unsigned char)((value) >> 8); \
269 (cp)[3] = (unsigned char)(value); }
271 /* Enumeration values for fields in SSH-1 packets */
273 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
274 /* These values are for communicating relevant semantics of
275 * fields to the packet logging code. */
276 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
280 * Coroutine mechanics for the sillier bits of the code. If these
281 * macros look impenetrable to you, you might find it helpful to
284 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
286 * which explains the theory behind these macros.
288 * In particular, if you are getting `case expression not constant'
289 * errors when building with MS Visual Studio, this is because MS's
290 * Edit and Continue debugging feature causes their compiler to
291 * violate ANSI C. To disable Edit and Continue debugging:
293 * - right-click ssh.c in the FileView
295 * - select the C/C++ tab and the General category
296 * - under `Debug info:', select anything _other_ than `Program
297 * Database for Edit and Continue'.
299 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
302 if (!ssh->t) ssh->t = snew(struct t); \
304 #define crFinish(z) } *crLine = 0; return (z); }
305 #define crFinishV } *crLine = 0; return; }
306 #define crReturn(z) \
308 *crLine =__LINE__; return (z); case __LINE__:;\
312 *crLine=__LINE__; return; case __LINE__:;\
314 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
315 #define crStopV do{ *crLine = 0; return; }while(0)
316 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
317 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
319 typedef struct ssh_tag
*Ssh
;
322 static struct Packet
*ssh2_pkt_init(int pkt_type
);
323 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
324 static void ssh2_pkt_adduint32(struct Packet
*, unsigned long value
);
325 static void ssh2_pkt_addstring_start(struct Packet
*);
326 static void ssh2_pkt_addstring_str(struct Packet
*, char *data
);
327 static void ssh2_pkt_addstring_data(struct Packet
*, char *data
, int len
);
328 static void ssh2_pkt_addstring(struct Packet
*, char *data
);
329 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
330 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
331 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
332 static void ssh2_pkt_send(Ssh
, struct Packet
*);
333 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
334 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
335 struct Packet
*pktin
);
336 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
337 struct Packet
*pktin
);
340 * Buffer management constants. There are several of these for
341 * various different purposes:
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
360 #define SSH1_BUFFER_LIMIT 32768
361 #define SSH_MAX_BACKLOG 32768
362 #define OUR_V2_WINSIZE 16384
363 #define OUR_V2_MAXPKT 0x4000UL
365 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
367 static void *nullmac_make_context(void)
371 static void nullmac_free_context(void *handle
)
374 static void nullmac_key(void *handle
, unsigned char *key
)
377 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
381 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
386 const static struct ssh_mac ssh_mac_none
= {
387 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
388 nullmac_generate
, nullmac_verify
, "none", 0
390 const static struct ssh_mac
*macs
[] = {
391 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
393 const static struct ssh_mac
*buggymacs
[] = {
394 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
397 static void *ssh_comp_none_init(void)
401 static void ssh_comp_none_cleanup(void *handle
)
404 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
405 unsigned char **outblock
, int *outlen
)
409 static int ssh_comp_none_disable(void *handle
)
413 const static struct ssh_compress ssh_comp_none
= {
415 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
416 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
417 ssh_comp_none_disable
, NULL
419 extern const struct ssh_compress ssh_zlib
;
420 const static struct ssh_compress
*compressions
[] = {
421 &ssh_zlib
, &ssh_comp_none
424 enum { /* channel types */
429 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
433 * 2-3-4 tree storing channels.
436 Ssh ssh
; /* pointer back to main context */
437 unsigned remoteid
, localid
;
439 /* True if we opened this channel but server hasn't confirmed. */
442 * In SSH1, this value contains four bits:
444 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
445 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
447 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
449 * A channel is completely finished with when all four bits are set.
453 struct ssh1_data_channel
{
456 struct ssh2_data_channel
{
458 unsigned remwindow
, remmaxpkt
;
463 struct ssh_agent_channel
{
464 unsigned char *message
;
465 unsigned char msglen
[4];
466 unsigned lensofar
, totallen
;
468 struct ssh_x11_channel
{
471 struct ssh_pfd_channel
{
478 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
479 * 2 use this structure in different ways, reflecting SSH 2's
480 * altogether saner approach to port forwarding.
482 * In SSH 1, you arrange a remote forwarding by sending the server
483 * the remote port number, and the local destination host:port.
484 * When a connection comes in, the server sends you back that
485 * host:port pair, and you connect to it. This is a ready-made
486 * security hole if you're not on the ball: a malicious server
487 * could send you back _any_ host:port pair, so if you trustingly
488 * connect to the address it gives you then you've just opened the
489 * entire inside of your corporate network just by connecting
490 * through it to a dodgy SSH server. Hence, we must store a list of
491 * host:port pairs we _are_ trying to forward to, and reject a
492 * connection request from the server if it's not in the list.
494 * In SSH 2, each side of the connection minds its own business and
495 * doesn't send unnecessary information to the other. You arrange a
496 * remote forwarding by sending the server just the remote port
497 * number. When a connection comes in, the server tells you which
498 * of its ports was connected to; and _you_ have to remember what
499 * local host:port pair went with that port number.
501 * Hence, in SSH 1 this structure is indexed by destination
502 * host:port pair, whereas in SSH 2 it is indexed by source port.
504 struct ssh_portfwd
; /* forward declaration */
506 struct ssh_rportfwd
{
507 unsigned sport
, dport
;
510 struct ssh_portfwd
*pfrec
;
512 #define free_rportfwd(pf) ( \
513 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
516 * Separately to the rportfwd tree (which is for looking up port
517 * open requests from the server), a tree of _these_ structures is
518 * used to keep track of all the currently open port forwardings,
519 * so that we can reconfigure in mid-session if the user requests
523 enum { DESTROY
, KEEP
, CREATE
} status
;
525 unsigned sport
, dport
;
528 struct ssh_rportfwd
*remote
;
532 #define free_portfwd(pf) ( \
533 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
534 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
538 long forcepad
; /* Force padding to at least this length */
540 unsigned long sequence
;
545 long encrypted_len
; /* for SSH2 total-size counting */
548 * State associated with packet logging
552 struct logblank_t
*blanks
;
555 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
556 struct Packet
*pktin
);
557 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
558 struct Packet
*pktin
);
559 static void ssh1_protocol_setup(Ssh ssh
);
560 static void ssh2_protocol_setup(Ssh ssh
);
561 static void ssh_size(void *handle
, int width
, int height
);
562 static void ssh_special(void *handle
, Telnet_Special
);
563 static int ssh2_try_send(struct ssh_channel
*c
);
564 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
565 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
566 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
567 static int ssh_sendbuffer(void *handle
);
568 static int ssh_do_close(Ssh ssh
, int notify_exit
);
569 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
570 static int ssh2_pkt_getbool(struct Packet
*pkt
);
571 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
572 static void ssh2_timer(void *ctx
, long now
);
573 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
574 struct Packet
*pktin
);
576 struct rdpkt1_state_tag
{
577 long len
, pad
, biglen
, to_read
;
578 unsigned long realcrc
, gotcrc
;
582 struct Packet
*pktin
;
585 struct rdpkt2_state_tag
{
586 long len
, pad
, payload
, packetlen
, maclen
;
589 unsigned long incoming_sequence
;
590 struct Packet
*pktin
;
593 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
594 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
596 struct queued_handler
;
597 struct queued_handler
{
599 chandler_fn_t handler
;
601 struct queued_handler
*next
;
605 const struct plug_function_table
*fn
;
606 /* the above field _must_ be first in the structure */
608 SHA_State exhash
, exhashbase
;
615 unsigned char session_key
[32];
617 int v1_remote_protoflags
;
618 int v1_local_protoflags
;
619 int agentfwd_enabled
;
622 const struct ssh_cipher
*cipher
;
625 const struct ssh2_cipher
*cscipher
, *sccipher
;
626 void *cs_cipher_ctx
, *sc_cipher_ctx
;
627 const struct ssh_mac
*csmac
, *scmac
;
628 void *cs_mac_ctx
, *sc_mac_ctx
;
629 const struct ssh_compress
*cscomp
, *sccomp
;
630 void *cs_comp_ctx
, *sc_comp_ctx
;
631 const struct ssh_kex
*kex
;
632 const struct ssh_signkey
*hostkey
;
633 unsigned char v2_session_id
[20];
639 int echoing
, editing
;
643 int ospeed
, ispeed
; /* temporaries */
644 int term_width
, term_height
;
646 tree234
*channels
; /* indexed by local id */
647 struct ssh_channel
*mainchan
; /* primary session channel */
651 tree234
*rportfwds
, *portfwds
;
655 SSH_STATE_BEFORE_SIZE
,
661 int size_needed
, eof_needed
;
663 struct Packet
**queue
;
664 int queuelen
, queuesize
;
666 unsigned char *deferred_send_data
;
667 int deferred_len
, deferred_size
;
670 * Gross hack: pscp will try to start SFTP but fall back to
671 * scp1 if that fails. This variable is the means by which
672 * scp.c can reach into the SSH code and find out which one it
678 * Used for username and password input.
680 char *userpass_input_buffer
;
681 int userpass_input_buflen
;
682 int userpass_input_bufpos
;
683 int userpass_input_echo
;
690 int v1_throttle_count
;
693 int v1_stdout_throttling
;
694 unsigned long v2_outgoing_sequence
;
696 int ssh1_rdpkt_crstate
;
697 int ssh2_rdpkt_crstate
;
698 int do_ssh_init_crstate
;
699 int ssh_gotdata_crstate
;
700 int do_ssh1_login_crstate
;
701 int do_ssh1_connection_crstate
;
702 int do_ssh2_transport_crstate
;
703 int do_ssh2_authconn_crstate
;
705 void *do_ssh_init_state
;
706 void *do_ssh1_login_state
;
707 void *do_ssh2_transport_state
;
708 void *do_ssh2_authconn_state
;
710 struct rdpkt1_state_tag rdpkt1_state
;
711 struct rdpkt2_state_tag rdpkt2_state
;
713 /* ssh1 and ssh2 use this for different things, but both use it */
714 int protocol_initial_phase_done
;
716 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
718 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
721 * We maintain a full _copy_ of a Config structure here, not
722 * merely a pointer to it. That way, when we're passed a new
723 * one for reconfiguration, we can check the differences and
724 * potentially reconfigure port forwardings etc in mid-session.
729 * Used to transfer data back from async agent callbacks.
731 void *agent_response
;
732 int agent_response_len
;
735 * Dispatch table for packet types that we may have to deal
738 handler_fn_t packet_dispatch
[256];
741 * Queues of one-off handler functions for success/failure
742 * indications from a request.
744 struct queued_handler
*qhead
, *qtail
;
747 * This module deals with sending keepalives.
752 * Track incoming and outgoing data sizes and time, for
755 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
756 unsigned long max_data_size
;
758 long next_rekey
, last_rekey
;
759 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
762 #define logevent(s) logevent(ssh->frontend, s)
764 /* logevent, only printf-formatted. */
765 static void logeventf(Ssh ssh
, const char *fmt
, ...)
771 buf
= dupvprintf(fmt
, ap
);
777 #define bombout(msg) \
779 char *text = dupprintf msg; \
780 ssh_do_close(ssh, FALSE); \
782 connection_fatal(ssh->frontend, "%s", text); \
786 /* Functions to leave bits out of the SSH packet log file. */
788 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
790 if (ssh
->cfg
.logomitpass
)
791 pkt
->logmode
= blanktype
;
794 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
796 if (ssh
->cfg
.logomitdata
)
797 pkt
->logmode
= blanktype
;
800 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
802 pkt
->logmode
= PKTLOG_EMIT
;
805 static int ssh_channelcmp(void *av
, void *bv
)
807 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
808 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
809 if (a
->localid
< b
->localid
)
811 if (a
->localid
> b
->localid
)
815 static int ssh_channelfind(void *av
, void *bv
)
817 unsigned *a
= (unsigned *) av
;
818 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
826 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
828 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
829 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
831 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
832 return i
< 0 ?
-1 : +1;
833 if (a
->dport
> b
->dport
)
835 if (a
->dport
< b
->dport
)
840 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
842 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
843 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
845 if (a
->sport
> b
->sport
)
847 if (a
->sport
< b
->sport
)
853 * Special form of strcmp which can cope with NULL inputs. NULL is
854 * defined to sort before even the empty string.
856 static int nullstrcmp(const char *a
, const char *b
)
858 if (a
== NULL
&& b
== NULL
)
867 static int ssh_portcmp(void *av
, void *bv
)
869 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
870 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
872 if (a
->type
> b
->type
)
874 if (a
->type
< b
->type
)
876 if (a
->addressfamily
> b
->addressfamily
)
878 if (a
->addressfamily
< b
->addressfamily
)
880 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
881 return i
< 0 ?
-1 : +1;
882 if (a
->sport
> b
->sport
)
884 if (a
->sport
< b
->sport
)
886 if (a
->type
!= 'D') {
887 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
888 return i
< 0 ?
-1 : +1;
889 if (a
->dport
> b
->dport
)
891 if (a
->dport
< b
->dport
)
897 static int alloc_channel_id(Ssh ssh
)
899 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
900 unsigned low
, high
, mid
;
902 struct ssh_channel
*c
;
905 * First-fit allocation of channel numbers: always pick the
906 * lowest unused one. To do this, binary-search using the
907 * counted B-tree to find the largest channel ID which is in a
908 * contiguous sequence from the beginning. (Precisely
909 * everything in that sequence must have ID equal to its tree
910 * index plus CHANNEL_NUMBER_OFFSET.)
912 tsize
= count234(ssh
->channels
);
916 while (high
- low
> 1) {
917 mid
= (high
+ low
) / 2;
918 c
= index234(ssh
->channels
, mid
);
919 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
920 low
= mid
; /* this one is fine */
922 high
= mid
; /* this one is past it */
925 * Now low points to either -1, or the tree index of the
926 * largest ID in the initial sequence.
929 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
930 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
932 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
935 static void c_write(Ssh ssh
, const char *buf
, int len
)
937 if ((flags
& FLAG_STDERR
)) {
939 for (i
= 0; i
< len
; i
++)
941 fputc(buf
[i
], stderr
);
944 from_backend(ssh
->frontend
, 1, buf
, len
);
947 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
950 for (i
= 0; i
< len
; i
++) {
952 c_write(ssh
, "\r\n", 2);
953 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
954 c_write(ssh
, buf
+ i
, 1);
958 static void c_write_str(Ssh ssh
, const char *buf
)
960 c_write(ssh
, buf
, strlen(buf
));
963 static void ssh_free_packet(struct Packet
*pkt
)
968 static struct Packet
*ssh_new_packet(void)
970 struct Packet
*pkt
= snew(struct Packet
);
974 pkt
->logmode
= PKTLOG_EMIT
;
982 * Collect incoming data in the incoming packet buffer.
983 * Decipher and verify the packet when it is completely read.
984 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
985 * Update the *data and *datalen variables.
986 * Return a Packet structure when a packet is completed.
988 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
990 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
992 crBegin(ssh
->ssh1_rdpkt_crstate
);
994 st
->pktin
= ssh_new_packet();
997 st
->pktin
->length
= 0;
999 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
1000 while ((*datalen
) == 0)
1002 st
->len
= (st
->len
<< 8) + **data
;
1003 (*data
)++, (*datalen
)--;
1006 st
->pad
= 8 - (st
->len
% 8);
1007 st
->biglen
= st
->len
+ st
->pad
;
1008 st
->pktin
->length
= st
->len
- 5;
1010 if (st
->biglen
< 0) {
1011 bombout(("Extremely large packet length from server suggests"
1012 " data stream corruption"));
1013 ssh_free_packet(st
->pktin
);
1017 st
->pktin
->maxlen
= st
->biglen
;
1018 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1020 st
->to_read
= st
->biglen
;
1021 st
->p
= st
->pktin
->data
;
1022 while (st
->to_read
> 0) {
1023 st
->chunk
= st
->to_read
;
1024 while ((*datalen
) == 0)
1026 if (st
->chunk
> (*datalen
))
1027 st
->chunk
= (*datalen
);
1028 memcpy(st
->p
, *data
, st
->chunk
);
1030 *datalen
-= st
->chunk
;
1032 st
->to_read
-= st
->chunk
;
1035 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1036 st
->biglen
, NULL
)) {
1037 bombout(("Network attack (CRC compensation) detected!"));
1038 ssh_free_packet(st
->pktin
);
1043 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1045 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1046 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1047 if (st
->gotcrc
!= st
->realcrc
) {
1048 bombout(("Incorrect CRC received on packet"));
1049 ssh_free_packet(st
->pktin
);
1053 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1054 st
->pktin
->savedpos
= 0;
1056 if (ssh
->v1_compressing
) {
1057 unsigned char *decompblk
;
1059 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1060 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1061 &decompblk
, &decomplen
)) {
1062 bombout(("Zlib decompression encountered invalid data"));
1063 ssh_free_packet(st
->pktin
);
1067 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1068 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1069 st
->pktin
->data
= sresize(st
->pktin
->data
,
1070 st
->pktin
->maxlen
+ APIEXTRA
,
1072 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1075 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1077 st
->pktin
->length
= decomplen
- 1;
1080 st
->pktin
->type
= st
->pktin
->body
[-1];
1083 * Log incoming packet, possibly omitting sensitive fields.
1087 struct logblank_t blank
;
1088 if (ssh
->cfg
.logomitdata
) {
1089 int do_blank
= FALSE
, blank_prefix
= 0;
1090 /* "Session data" packets - omit the data field */
1091 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1092 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1093 do_blank
= TRUE
; blank_prefix
= 0;
1094 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1095 do_blank
= TRUE
; blank_prefix
= 4;
1098 blank
.offset
= blank_prefix
;
1099 blank
.len
= st
->pktin
->length
;
1100 blank
.type
= PKTLOG_OMIT
;
1104 log_packet(ssh
->logctx
,
1105 PKT_INCOMING
, st
->pktin
->type
,
1106 ssh1_pkt_type(st
->pktin
->type
),
1107 st
->pktin
->body
, st
->pktin
->length
,
1111 crFinish(st
->pktin
);
1114 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1116 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1118 crBegin(ssh
->ssh2_rdpkt_crstate
);
1120 st
->pktin
= ssh_new_packet();
1122 st
->pktin
->type
= 0;
1123 st
->pktin
->length
= 0;
1125 st
->cipherblk
= ssh
->sccipher
->blksize
;
1128 if (st
->cipherblk
< 8)
1131 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1134 * Acquire and decrypt the first block of the packet. This will
1135 * contain the length and padding details.
1137 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1138 while ((*datalen
) == 0)
1140 st
->pktin
->data
[st
->i
] = *(*data
)++;
1145 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1146 st
->pktin
->data
, st
->cipherblk
);
1149 * Now get the length and padding figures.
1151 st
->len
= GET_32BIT(st
->pktin
->data
);
1152 st
->pad
= st
->pktin
->data
[4];
1155 * _Completely_ silly lengths should be stomped on before they
1156 * do us any more damage.
1158 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1159 bombout(("Incoming packet was garbled on decryption"));
1160 ssh_free_packet(st
->pktin
);
1165 * This enables us to deduce the payload length.
1167 st
->payload
= st
->len
- st
->pad
- 1;
1169 st
->pktin
->length
= st
->payload
+ 5;
1172 * So now we can work out the total packet length.
1174 st
->packetlen
= st
->len
+ 4;
1175 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1178 * Allocate memory for the rest of the packet.
1180 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1181 st
->pktin
->data
= sresize(st
->pktin
->data
,
1182 st
->pktin
->maxlen
+ APIEXTRA
,
1186 * Read and decrypt the remainder of the packet.
1188 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1190 while ((*datalen
) == 0)
1192 st
->pktin
->data
[st
->i
] = *(*data
)++;
1195 /* Decrypt everything _except_ the MAC. */
1197 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1198 st
->pktin
->data
+ st
->cipherblk
,
1199 st
->packetlen
- st
->cipherblk
);
1201 st
->pktin
->encrypted_len
= st
->packetlen
;
1207 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1208 st
->incoming_sequence
)) {
1209 bombout(("Incorrect MAC received on packet"));
1210 ssh_free_packet(st
->pktin
);
1214 st
->pktin
->sequence
= st
->incoming_sequence
++;
1217 * Decompress packet payload.
1220 unsigned char *newpayload
;
1223 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1224 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1225 &newpayload
, &newlen
)) {
1226 if (st
->pktin
->maxlen
< newlen
+ 5) {
1227 st
->pktin
->maxlen
= newlen
+ 5;
1228 st
->pktin
->data
= sresize(st
->pktin
->data
,
1229 st
->pktin
->maxlen
+ APIEXTRA
,
1232 st
->pktin
->length
= 5 + newlen
;
1233 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1238 st
->pktin
->savedpos
= 6;
1239 st
->pktin
->body
= st
->pktin
->data
;
1240 st
->pktin
->type
= st
->pktin
->data
[5];
1243 * Log incoming packet, possibly omitting sensitive fields.
1247 struct logblank_t blank
;
1248 if (ssh
->cfg
.logomitdata
) {
1249 int do_blank
= FALSE
, blank_prefix
= 0;
1250 /* "Session data" packets - omit the data field */
1251 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1252 do_blank
= TRUE
; blank_prefix
= 4;
1253 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1254 do_blank
= TRUE
; blank_prefix
= 8;
1257 blank
.offset
= blank_prefix
;
1258 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1259 blank
.type
= PKTLOG_OMIT
;
1263 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1264 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1265 st
->pktin
->data
+6, st
->pktin
->length
-6,
1269 crFinish(st
->pktin
);
1272 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1276 len
+= 5; /* type and CRC */
1277 pad
= 8 - (len
% 8);
1280 pkt
->length
= len
- 5;
1281 if (pkt
->maxlen
< biglen
) {
1282 pkt
->maxlen
= biglen
;
1283 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1285 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1288 static struct Packet
*s_wrpkt_start(int type
, int len
)
1290 struct Packet
*pkt
= ssh_new_packet();
1291 ssh1_pktout_size(pkt
, len
);
1293 /* Initialise log omission state */
1299 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1305 * XXX various versions of SC (including 8.8.4) screw up the
1306 * register allocation in this function and use the same register
1307 * (D6) for len and as a temporary, with predictable results. The
1308 * following sledgehammer prevents this.
1314 pkt
->body
[-1] = pkt
->type
;
1317 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1318 ssh1_pkt_type(pkt
->type
),
1319 pkt
->body
, pkt
->length
,
1320 pkt
->nblanks
, pkt
->blanks
);
1321 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1324 if (ssh
->v1_compressing
) {
1325 unsigned char *compblk
;
1327 zlib_compress_block(ssh
->cs_comp_ctx
,
1328 pkt
->body
- 1, pkt
->length
+ 1,
1329 &compblk
, &complen
);
1330 ssh1_pktout_size(pkt
, complen
- 1);
1331 memcpy(pkt
->body
- 1, compblk
, complen
);
1335 len
= pkt
->length
+ 5; /* type and CRC */
1336 pad
= 8 - (len
% 8);
1339 for (i
= 0; i
< pad
; i
++)
1340 pkt
->data
[i
+ 4] = random_byte();
1341 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1342 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1343 PUT_32BIT(pkt
->data
, len
);
1346 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1351 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1354 len
= s_wrpkt_prepare(ssh
, pkt
);
1355 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1356 if (backlog
> SSH_MAX_BACKLOG
)
1357 ssh_throttle_all(ssh
, 1, backlog
);
1360 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1363 len
= s_wrpkt_prepare(ssh
, pkt
);
1364 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1365 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1366 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1370 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1371 ssh
->deferred_len
+= len
;
1375 * Construct a packet with the specified contents.
1377 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1378 va_list ap1
, va_list ap2
)
1380 unsigned char *p
, *argp
, argchar
;
1381 unsigned long argint
;
1382 int pktlen
, argtype
, arglen
;
1387 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1390 (void) va_arg(ap1
, int);
1394 (void) va_arg(ap1
, int);
1398 (void) va_arg(ap1
, unsigned char *);
1399 arglen
= va_arg(ap1
, int);
1403 argp
= va_arg(ap1
, unsigned char *);
1404 arglen
= strlen((char *)argp
);
1405 pktlen
+= 4 + arglen
;
1408 bn
= va_arg(ap1
, Bignum
);
1409 pktlen
+= ssh1_bignum_length(bn
);
1414 /* ignore this pass */
1421 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1424 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1425 int offset
= p
- pkt
->body
, len
= 0;
1427 /* Actual fields in the packet */
1429 argint
= va_arg(ap2
, int);
1430 PUT_32BIT(p
, argint
);
1434 argchar
= (unsigned char) va_arg(ap2
, int);
1439 argp
= va_arg(ap2
, unsigned char *);
1440 arglen
= va_arg(ap2
, int);
1441 memcpy(p
, argp
, arglen
);
1445 argp
= va_arg(ap2
, unsigned char *);
1446 arglen
= strlen((char *)argp
);
1447 PUT_32BIT(p
, arglen
);
1448 memcpy(p
+ 4, argp
, arglen
);
1452 bn
= va_arg(ap2
, Bignum
);
1453 len
= ssh1_write_bignum(p
, bn
);
1455 /* Tokens for modifications to packet logging */
1457 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1460 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1463 end_log_omission(ssh
, pkt
);
1467 /* Deal with logfile omission, if required. */
1468 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1470 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1472 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1473 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1474 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1481 static void send_packet(Ssh ssh
, int pkttype
, ...)
1485 va_start(ap1
, pkttype
);
1486 va_start(ap2
, pkttype
);
1487 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1491 ssh_free_packet(pkt
);
1494 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1498 va_start(ap1
, pkttype
);
1499 va_start(ap2
, pkttype
);
1500 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1503 s_wrpkt_defer(ssh
, pkt
);
1504 ssh_free_packet(pkt
);
1507 static int ssh_versioncmp(char *a
, char *b
)
1510 unsigned long av
, bv
;
1512 av
= strtoul(a
, &ae
, 10);
1513 bv
= strtoul(b
, &be
, 10);
1515 return (av
< bv ?
-1 : +1);
1520 av
= strtoul(ae
, &ae
, 10);
1521 bv
= strtoul(be
, &be
, 10);
1523 return (av
< bv ?
-1 : +1);
1528 * Utility routines for putting an SSH-protocol `string' and
1529 * `uint32' into a SHA state.
1532 static void sha_string(SHA_State
* s
, void *str
, int len
)
1534 unsigned char lenblk
[4];
1535 PUT_32BIT(lenblk
, len
);
1536 SHA_Bytes(s
, lenblk
, 4);
1537 SHA_Bytes(s
, str
, len
);
1540 static void sha_uint32(SHA_State
* s
, unsigned i
)
1542 unsigned char intblk
[4];
1543 PUT_32BIT(intblk
, i
);
1544 SHA_Bytes(s
, intblk
, 4);
1548 * SSH2 packet construction functions.
1550 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1552 if (pkt
->maxlen
< length
) {
1553 pkt
->maxlen
= length
+ 256;
1554 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1557 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1559 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1561 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1562 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1563 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1564 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1567 ssh2_pkt_ensure(pkt
, pkt
->length
);
1568 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1570 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1572 ssh2_pkt_adddata(pkt
, &byte
, 1);
1574 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1576 struct Packet
*pkt
= ssh_new_packet();
1579 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1582 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1584 ssh2_pkt_adddata(pkt
, &value
, 1);
1586 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1589 PUT_32BIT(x
, value
);
1590 ssh2_pkt_adddata(pkt
, x
, 4);
1592 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1594 ssh2_pkt_adduint32(pkt
, 0);
1595 pkt
->savedpos
= pkt
->length
;
1597 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1599 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1600 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1602 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1604 ssh2_pkt_adddata(pkt
, data
, len
);
1605 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1607 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1609 ssh2_pkt_addstring_start(pkt
);
1610 ssh2_pkt_addstring_str(pkt
, data
);
1612 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1615 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1616 p
= snewn(n
+ 1, unsigned char);
1618 fatalbox("out of memory");
1620 for (i
= 1; i
<= n
; i
++)
1621 p
[i
] = bignum_byte(b
, n
- i
);
1623 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1625 memmove(p
, p
+ i
, n
+ 1 - i
);
1629 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1633 p
= ssh2_mpint_fmt(b
, &len
);
1634 ssh2_pkt_addstring_start(pkt
);
1635 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1640 * Construct an SSH2 final-form packet: compress it, encrypt it,
1641 * put the MAC on it. Final packet, ready to be sent, is stored in
1642 * pkt->data. Total length is returned.
1644 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1646 int cipherblk
, maclen
, padding
, i
;
1649 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1650 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1651 pkt
->data
+ 6, pkt
->length
- 6,
1652 pkt
->nblanks
, pkt
->blanks
);
1653 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1657 * Compress packet payload.
1660 unsigned char *newpayload
;
1663 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1665 &newpayload
, &newlen
)) {
1667 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1673 * Add padding. At least four bytes, and must also bring total
1674 * length (minus MAC) up to a multiple of the block size.
1675 * If pkt->forcepad is set, make sure the packet is at least that size
1678 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1679 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1681 if (pkt
->length
+ padding
< pkt
->forcepad
)
1682 padding
= pkt
->forcepad
- pkt
->length
;
1684 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1685 assert(padding
<= 255);
1686 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1687 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1688 pkt
->data
[4] = padding
;
1689 for (i
= 0; i
< padding
; i
++)
1690 pkt
->data
[pkt
->length
+ i
] = random_byte();
1691 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1693 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1694 pkt
->length
+ padding
,
1695 ssh
->v2_outgoing_sequence
);
1696 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1699 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1700 pkt
->data
, pkt
->length
+ padding
);
1702 pkt
->encrypted_len
= pkt
->length
+ padding
;
1704 /* Ready-to-send packet starts at pkt->data. We return length. */
1705 return pkt
->length
+ padding
+ maclen
;
1709 * Routines called from the main SSH code to send packets. There
1710 * are quite a few of these, because we have two separate
1711 * mechanisms for delaying the sending of packets:
1713 * - In order to send an IGNORE message and a password message in
1714 * a single fixed-length blob, we require the ability to
1715 * concatenate the encrypted forms of those two packets _into_ a
1716 * single blob and then pass it to our <network.h> transport
1717 * layer in one go. Hence, there's a deferment mechanism which
1718 * works after packet encryption.
1720 * - In order to avoid sending any connection-layer messages
1721 * during repeat key exchange, we have to queue up any such
1722 * outgoing messages _before_ they are encrypted (and in
1723 * particular before they're allocated sequence numbers), and
1724 * then send them once we've finished.
1726 * I call these mechanisms `defer' and `queue' respectively, so as
1727 * to distinguish them reasonably easily.
1729 * The functions send_noqueue() and defer_noqueue() free the packet
1730 * structure they are passed. Every outgoing packet goes through
1731 * precisely one of these functions in its life; packets passed to
1732 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1733 * these or get queued, and then when the queue is later emptied
1734 * the packets are all passed to defer_noqueue().
1738 * Send an SSH2 packet immediately, without queuing or deferring.
1740 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1744 len
= ssh2_pkt_construct(ssh
, pkt
);
1745 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1746 if (backlog
> SSH_MAX_BACKLOG
)
1747 ssh_throttle_all(ssh
, 1, backlog
);
1749 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1750 if (!ssh
->kex_in_progress
&&
1751 ssh
->max_data_size
!= 0 &&
1752 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1753 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1755 ssh_free_packet(pkt
);
1759 * Defer an SSH2 packet.
1761 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1763 int len
= ssh2_pkt_construct(ssh
, pkt
);
1764 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1765 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1766 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1770 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1771 ssh
->deferred_len
+= len
;
1772 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1773 ssh_free_packet(pkt
);
1777 * Queue an SSH2 packet.
1779 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1781 assert(ssh
->queueing
);
1783 if (ssh
->queuelen
>= ssh
->queuesize
) {
1784 ssh
->queuesize
= ssh
->queuelen
+ 32;
1785 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1788 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1792 * Either queue or send a packet, depending on whether queueing is
1795 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1798 ssh2_pkt_queue(ssh
, pkt
);
1800 ssh2_pkt_send_noqueue(ssh
, pkt
);
1805 * Either queue or defer a packet, depending on whether queueing is
1808 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1811 ssh2_pkt_queue(ssh
, pkt
);
1813 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1818 * Send the whole deferred data block constructed by
1819 * ssh2_pkt_defer() or SSH1's defer_packet().
1821 * The expected use of the defer mechanism is that you call
1822 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1823 * not currently queueing, this simply sets up deferred_send_data
1824 * and then sends it. If we _are_ currently queueing, the calls to
1825 * ssh2_pkt_defer() put the deferred packets on to the queue
1826 * instead, and therefore ssh_pkt_defersend() has no deferred data
1827 * to send. Hence, there's no need to make it conditional on
1830 static void ssh_pkt_defersend(Ssh ssh
)
1833 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1835 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1836 sfree(ssh
->deferred_send_data
);
1837 ssh
->deferred_send_data
= NULL
;
1838 if (backlog
> SSH_MAX_BACKLOG
)
1839 ssh_throttle_all(ssh
, 1, backlog
);
1841 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1842 if (!ssh
->kex_in_progress
&&
1843 ssh
->max_data_size
!= 0 &&
1844 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1845 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1846 ssh
->deferred_data_size
= 0;
1850 * Send all queued SSH2 packets. We send them by means of
1851 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1852 * packets that needed to be lumped together.
1854 static void ssh2_pkt_queuesend(Ssh ssh
)
1858 assert(!ssh
->queueing
);
1860 for (i
= 0; i
< ssh
->queuelen
; i
++)
1861 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1864 ssh_pkt_defersend(ssh
);
1868 void bndebug(char *string
, Bignum b
)
1872 p
= ssh2_mpint_fmt(b
, &len
);
1873 debug(("%s", string
));
1874 for (i
= 0; i
< len
; i
++)
1875 debug((" %02x", p
[i
]));
1881 static void sha_mpint(SHA_State
* s
, Bignum b
)
1885 p
= ssh2_mpint_fmt(b
, &len
);
1886 sha_string(s
, p
, len
);
1891 * Packet decode functions for both SSH1 and SSH2.
1893 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1895 unsigned long value
;
1896 if (pkt
->length
- pkt
->savedpos
< 4)
1897 return 0; /* arrgh, no way to decline (FIXME?) */
1898 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1902 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1904 unsigned long value
;
1905 if (pkt
->length
- pkt
->savedpos
< 1)
1906 return 0; /* arrgh, no way to decline (FIXME?) */
1907 value
= pkt
->body
[pkt
->savedpos
] != 0;
1911 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1916 if (pkt
->length
- pkt
->savedpos
< 4)
1918 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1923 if (pkt
->length
- pkt
->savedpos
< *length
)
1925 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1926 pkt
->savedpos
+= *length
;
1928 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1930 if (pkt
->length
- pkt
->savedpos
< length
)
1932 pkt
->savedpos
+= length
;
1933 return pkt
->body
+ (pkt
->savedpos
- length
);
1935 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1936 unsigned char **keystr
)
1940 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1941 pkt
->length
- pkt
->savedpos
,
1948 assert(pkt
->savedpos
< pkt
->length
);
1952 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1957 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1958 pkt
->length
- pkt
->savedpos
, &b
);
1966 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1972 ssh_pkt_getstring(pkt
, &p
, &length
);
1977 b
= bignum_from_bytes((unsigned char *)p
, length
);
1982 * Helper function to add an SSH2 signature blob to a packet.
1983 * Expects to be shown the public key blob as well as the signature
1984 * blob. Normally works just like ssh2_pkt_addstring, but will
1985 * fiddle with the signature packet if necessary for
1986 * BUG_SSH2_RSA_PADDING.
1988 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1989 void *pkblob_v
, int pkblob_len
,
1990 void *sigblob_v
, int sigblob_len
)
1992 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1993 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1995 /* dmemdump(pkblob, pkblob_len); */
1996 /* dmemdump(sigblob, sigblob_len); */
1999 * See if this is in fact an ssh-rsa signature and a buggy
2000 * server; otherwise we can just do this the easy way.
2002 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
2003 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
2004 int pos
, len
, siglen
;
2007 * Find the byte length of the modulus.
2010 pos
= 4+7; /* skip over "ssh-rsa" */
2011 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2012 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2013 pos
+= 4; /* find modulus itself */
2014 while (len
> 0 && pkblob
[pos
] == 0)
2016 /* debug(("modulus length is %d\n", len)); */
2019 * Now find the signature integer.
2021 pos
= 4+7; /* skip over "ssh-rsa" */
2022 siglen
= GET_32BIT(sigblob
+pos
);
2023 /* debug(("signature length is %d\n", siglen)); */
2025 if (len
!= siglen
) {
2026 unsigned char newlen
[4];
2027 ssh2_pkt_addstring_start(pkt
);
2028 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2029 /* dmemdump(sigblob, pos); */
2030 pos
+= 4; /* point to start of actual sig */
2031 PUT_32BIT(newlen
, len
);
2032 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2033 /* dmemdump(newlen, 4); */
2035 while (len
-- > siglen
) {
2036 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2037 /* dmemdump(newlen, 1); */
2039 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2040 /* dmemdump(sigblob+pos, siglen); */
2044 /* Otherwise fall through and do it the easy way. */
2047 ssh2_pkt_addstring_start(pkt
);
2048 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2052 * Examine the remote side's version string and compare it against
2053 * a list of known buggy implementations.
2055 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2057 char *imp
; /* pointer to implementation part */
2059 imp
+= strcspn(imp
, "-");
2061 imp
+= strcspn(imp
, "-");
2064 ssh
->remote_bugs
= 0;
2066 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2067 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2068 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2069 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2070 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2071 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2073 * These versions don't support SSH1_MSG_IGNORE, so we have
2074 * to use a different defence against password length
2077 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2078 logevent("We believe remote version has SSH1 ignore bug");
2081 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2082 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2083 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2085 * These versions need a plain password sent; they can't
2086 * handle having a null and a random length of data after
2089 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2090 logevent("We believe remote version needs a plain SSH1 password");
2093 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2094 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2095 (!strcmp(imp
, "Cisco-1.25")))) {
2097 * These versions apparently have no clue whatever about
2098 * RSA authentication and will panic and die if they see
2099 * an AUTH_RSA message.
2101 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2102 logevent("We believe remote version can't handle RSA authentication");
2105 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2106 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2107 !wc_match("* VShell", imp
) &&
2108 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2109 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2110 wc_match("2.1 *", imp
)))) {
2112 * These versions have the HMAC bug.
2114 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2115 logevent("We believe remote version has SSH2 HMAC bug");
2118 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2119 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2120 !wc_match("* VShell", imp
) &&
2121 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2123 * These versions have the key-derivation bug (failing to
2124 * include the literal shared secret in the hashes that
2125 * generate the keys).
2127 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2128 logevent("We believe remote version has SSH2 key-derivation bug");
2131 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2132 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2133 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2134 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2136 * These versions have the SSH2 RSA padding bug.
2138 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2139 logevent("We believe remote version has SSH2 RSA padding bug");
2142 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2143 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2144 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2146 * These versions have the SSH2 session-ID bug in
2147 * public-key authentication.
2149 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2150 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2153 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2154 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2155 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2156 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2157 wc_match("Sun_SSH_1.0", imp
) ||
2158 wc_match("Sun_SSH_1.0.1", imp
)))) {
2160 * These versions have the SSH2 rekey bug.
2162 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2163 logevent("We believe remote version has SSH2 rekey bug");
2168 * The `software version' part of an SSH version string is required
2169 * to contain no spaces or minus signs.
2171 static void ssh_fix_verstring(char *str
)
2173 /* Eat "SSH-<protoversion>-". */
2174 assert(*str
== 'S'); str
++;
2175 assert(*str
== 'S'); str
++;
2176 assert(*str
== 'H'); str
++;
2177 assert(*str
== '-'); str
++;
2178 while (*str
&& *str
!= '-') str
++;
2179 assert(*str
== '-'); str
++;
2181 /* Convert minus signs and spaces in the remaining string into
2184 if (*str
== '-' || *str
== ' ')
2190 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2192 struct do_ssh_init_state
{
2200 crState(do_ssh_init_state
);
2202 crBegin(ssh
->do_ssh_init_crstate
);
2204 /* Search for the string "SSH-" in the input. */
2207 static const int transS
[] = { 1, 2, 2, 1 };
2208 static const int transH
[] = { 0, 0, 3, 0 };
2209 static const int transminus
[] = { 0, 0, 0, -1 };
2211 s
->i
= transS
[s
->i
];
2213 s
->i
= transH
[s
->i
];
2215 s
->i
= transminus
[s
->i
];
2220 crReturn(1); /* get another character */
2224 s
->vstring
= snewn(s
->vstrsize
, char);
2225 strcpy(s
->vstring
, "SSH-");
2229 crReturn(1); /* get another char */
2230 if (s
->vslen
>= s
->vstrsize
- 1) {
2232 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2234 s
->vstring
[s
->vslen
++] = c
;
2237 s
->version
[s
->i
] = '\0';
2239 } else if (s
->i
< sizeof(s
->version
) - 1)
2240 s
->version
[s
->i
++] = c
;
2241 } else if (c
== '\012')
2245 ssh
->agentfwd_enabled
= FALSE
;
2246 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2248 s
->vstring
[s
->vslen
] = 0;
2249 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2252 vlog
= snewn(20 + s
->vslen
, char);
2253 sprintf(vlog
, "Server version: %s", s
->vstring
);
2257 ssh_detect_bugs(ssh
, s
->vstring
);
2260 * Decide which SSH protocol version to support.
2263 /* Anything strictly below "2.0" means protocol 1 is supported. */
2264 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2265 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2266 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2268 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2269 bombout(("SSH protocol version 1 required by user but not provided by server"));
2272 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2273 bombout(("SSH protocol version 2 required by user but not provided by server"));
2280 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2282 * Construct a v2 version string.
2284 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2288 * Construct a v1 version string.
2290 verstring
= dupprintf("SSH-%s-%s\012",
2291 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2292 s
->version
: "1.5"),
2297 ssh_fix_verstring(verstring
);
2299 if (ssh
->version
== 2) {
2301 * Hash our version string and their version string.
2303 SHA_Init(&ssh
->exhashbase
);
2304 sha_string(&ssh
->exhashbase
, verstring
,
2305 strcspn(verstring
, "\015\012"));
2306 sha_string(&ssh
->exhashbase
, s
->vstring
,
2307 strcspn(s
->vstring
, "\015\012"));
2310 * Initialise SSHv2 protocol.
2312 ssh
->protocol
= ssh2_protocol
;
2313 ssh2_protocol_setup(ssh
);
2314 ssh
->s_rdpkt
= ssh2_rdpkt
;
2317 * Initialise SSHv1 protocol.
2319 ssh
->protocol
= ssh1_protocol
;
2320 ssh1_protocol_setup(ssh
);
2321 ssh
->s_rdpkt
= ssh1_rdpkt
;
2323 logeventf(ssh
, "We claim version: %.*s",
2324 strcspn(verstring
, "\015\012"), verstring
);
2325 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2329 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2331 update_specials_menu(ssh
->frontend
);
2332 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2333 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2340 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2342 crBegin(ssh
->ssh_gotdata_crstate
);
2345 * To begin with, feed the characters one by one to the
2346 * protocol initialisation / selection function do_ssh_init().
2347 * When that returns 0, we're done with the initial greeting
2348 * exchange and can move on to packet discipline.
2351 int ret
; /* need not be kept across crReturn */
2353 crReturnV
; /* more data please */
2354 ret
= do_ssh_init(ssh
, *data
);
2362 * We emerge from that loop when the initial negotiation is
2363 * over and we have selected an s_rdpkt function. Now pass
2364 * everything to s_rdpkt, and then pass the resulting packets
2365 * to the proper protocol handler.
2370 while (datalen
> 0) {
2371 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2373 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2374 ssh_free_packet(pktin
);
2376 if (ssh
->state
== SSH_STATE_CLOSED
)
2384 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2387 struct ssh_channel
*c
;
2389 ssh
->state
= SSH_STATE_CLOSED
;
2394 notify_remote_exit(ssh
->frontend
);
2399 * Now we must shut down any port and X forwardings going
2400 * through this connection.
2402 if (ssh
->channels
) {
2403 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2406 x11_close(c
->u
.x11
.s
);
2409 pfd_close(c
->u
.pfd
.s
);
2412 del234(ssh
->channels
, c
);
2413 if (ssh
->version
== 2)
2414 bufchain_clear(&c
->v
.v2
.outbuffer
);
2422 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2423 const char *error_msg
, int error_code
)
2425 Ssh ssh
= (Ssh
) plug
;
2426 char addrbuf
[256], *msg
;
2428 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2431 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2433 msg
= dupprintf("Failed to connect to %s: %s", addrbuf
, error_msg
);
2438 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2441 Ssh ssh
= (Ssh
) plug
;
2442 int need_notify
= ssh_do_close(ssh
, FALSE
);
2444 if (!error_msg
&& !ssh
->close_expected
) {
2445 error_msg
= "Server unexpectedly closed network connection";
2449 /* A socket error has occurred. */
2450 logevent(error_msg
);
2451 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2453 logevent("Server closed network connection");
2456 notify_remote_exit(ssh
->frontend
);
2460 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2462 Ssh ssh
= (Ssh
) plug
;
2463 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2464 if (ssh
->state
== SSH_STATE_CLOSED
) {
2465 ssh_do_close(ssh
, TRUE
);
2471 static void ssh_sent(Plug plug
, int bufsize
)
2473 Ssh ssh
= (Ssh
) plug
;
2475 * If the send backlog on the SSH socket itself clears, we
2476 * should unthrottle the whole world if it was throttled.
2478 if (bufsize
< SSH_MAX_BACKLOG
)
2479 ssh_throttle_all(ssh
, 0, bufsize
);
2483 * Connect to specified host and port.
2484 * Returns an error message, or NULL on success.
2485 * Also places the canonical host name into `realhost'. It must be
2486 * freed by the caller.
2488 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2489 char **realhost
, int nodelay
, int keepalive
)
2491 static const struct plug_function_table fn_table
= {
2502 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2503 if (!ssh
->savedhost
)
2504 fatalbox("Out of memory");
2505 strcpy(ssh
->savedhost
, host
);
2508 port
= 22; /* default ssh port */
2509 ssh
->savedport
= port
;
2514 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2515 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2516 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2517 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2518 ssh
->cfg
.addressfamily
);
2519 if ((err
= sk_addr_error(addr
)) != NULL
) {
2527 ssh
->fn
= &fn_table
;
2528 ssh
->s
= new_connection(addr
, *realhost
, port
,
2529 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2530 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2532 notify_remote_exit(ssh
->frontend
);
2540 * Throttle or unthrottle the SSH connection.
2542 static void ssh1_throttle(Ssh ssh
, int adjust
)
2544 int old_count
= ssh
->v1_throttle_count
;
2545 ssh
->v1_throttle_count
+= adjust
;
2546 assert(ssh
->v1_throttle_count
>= 0);
2547 if (ssh
->v1_throttle_count
&& !old_count
) {
2548 sk_set_frozen(ssh
->s
, 1);
2549 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2550 sk_set_frozen(ssh
->s
, 0);
2555 * Throttle or unthrottle _all_ local data streams (for when sends
2556 * on the SSH connection itself back up).
2558 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2561 struct ssh_channel
*c
;
2563 if (enable
== ssh
->throttled_all
)
2565 ssh
->throttled_all
= enable
;
2566 ssh
->overall_bufsize
= bufsize
;
2569 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2571 case CHAN_MAINSESSION
:
2573 * This is treated separately, outside the switch.
2577 x11_override_throttle(c
->u
.x11
.s
, enable
);
2580 /* Agent channels require no buffer management. */
2583 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2590 * Username and password input, abstracted off into routines
2591 * reusable in several places - even between SSH1 and SSH2.
2594 /* Set up a username or password input loop on a given buffer. */
2595 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2597 ssh
->userpass_input_buffer
= buffer
;
2598 ssh
->userpass_input_buflen
= buflen
;
2599 ssh
->userpass_input_bufpos
= 0;
2600 ssh
->userpass_input_echo
= echo
;
2604 * Process some terminal data in the course of username/password
2605 * input. Returns >0 for success (line of input returned in
2606 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2607 * for inconclusive (keep waiting for more input please).
2609 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2614 switch (c
= *in
++) {
2617 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2618 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2623 if (ssh
->userpass_input_bufpos
> 0) {
2624 if (ssh
->userpass_input_echo
)
2625 c_write_str(ssh
, "\b \b");
2626 ssh
->userpass_input_bufpos
--;
2631 while (ssh
->userpass_input_bufpos
> 0) {
2632 if (ssh
->userpass_input_echo
)
2633 c_write_str(ssh
, "\b \b");
2634 ssh
->userpass_input_bufpos
--;
2643 * This simplistic check for printability is disabled
2644 * when we're doing password input, because some people
2645 * have control characters in their passwords.o
2647 if ((!ssh
->userpass_input_echo
||
2648 (c
>= ' ' && c
<= '~') ||
2649 ((unsigned char) c
>= 160))
2650 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2651 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2652 if (ssh
->userpass_input_echo
)
2653 c_write(ssh
, &c
, 1);
2661 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2663 Ssh ssh
= (Ssh
) sshv
;
2665 ssh
->agent_response
= reply
;
2666 ssh
->agent_response_len
= replylen
;
2668 if (ssh
->version
== 1)
2669 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2671 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2674 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2676 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2678 void *sentreply
= reply
;
2681 /* Fake SSH_AGENT_FAILURE. */
2682 sentreply
= "\0\0\0\1\5";
2685 if (ssh
->version
== 2) {
2686 ssh2_add_channel_data(c
, sentreply
, replylen
);
2689 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2690 PKT_INT
, c
->remoteid
,
2693 PKT_DATA
, sentreply
, replylen
,
2702 * Handle the key exchange and user authentication phases.
2704 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2705 struct Packet
*pktin
)
2708 unsigned char cookie
[8], *ptr
;
2709 struct RSAKey servkey
, hostkey
;
2710 struct MD5Context md5c
;
2711 struct do_ssh1_login_state
{
2713 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2714 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2715 int tried_publickey
, tried_agent
;
2716 int tis_auth_refused
, ccard_auth_refused
;
2717 unsigned char session_id
[16];
2720 void *publickey_blob
;
2721 int publickey_bloblen
;
2727 unsigned char request
[5], *response
, *p
;
2736 crState(do_ssh1_login_state
);
2738 crBegin(ssh
->do_ssh1_login_crstate
);
2743 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2744 bombout(("Public key packet not received"));
2748 logevent("Received public keys");
2750 ptr
= ssh_pkt_getdata(pktin
, 8);
2752 bombout(("SSH1 public key packet stopped before random cookie"));
2755 memcpy(cookie
, ptr
, 8);
2757 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2758 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2759 bombout(("Failed to read SSH1 public keys from public key packet"));
2764 * Log the host key fingerprint.
2768 logevent("Host key fingerprint is:");
2769 strcpy(logmsg
, " ");
2770 hostkey
.comment
= NULL
;
2771 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2772 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2776 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2777 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2778 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2780 ssh
->v1_local_protoflags
=
2781 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2782 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2785 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2786 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2787 MD5Update(&md5c
, cookie
, 8);
2788 MD5Final(s
->session_id
, &md5c
);
2790 for (i
= 0; i
< 32; i
++)
2791 ssh
->session_key
[i
] = random_byte();
2794 * Verify that the `bits' and `bytes' parameters match.
2796 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2797 servkey
.bits
> servkey
.bytes
* 8) {
2798 bombout(("SSH1 public keys were badly formatted"));
2802 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2804 s
->rsabuf
= snewn(s
->len
, unsigned char);
2806 fatalbox("Out of memory");
2809 * Verify the host key.
2813 * First format the key into a string.
2815 int len
= rsastr_len(&hostkey
);
2816 char fingerprint
[100];
2817 char *keystr
= snewn(len
, char);
2819 fatalbox("Out of memory");
2820 rsastr_fmt(keystr
, &hostkey
);
2821 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2822 verify_ssh_host_key(ssh
->frontend
,
2823 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2828 for (i
= 0; i
< 32; i
++) {
2829 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2831 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2834 if (hostkey
.bytes
> servkey
.bytes
) {
2835 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2837 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2839 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2841 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2844 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2848 logevent("Encrypted session key");
2851 int cipher_chosen
= 0, warn
= 0;
2852 char *cipher_string
= NULL
;
2854 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2855 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2856 if (next_cipher
== CIPHER_WARN
) {
2857 /* If/when we choose a cipher, warn about it */
2859 } else if (next_cipher
== CIPHER_AES
) {
2860 /* XXX Probably don't need to mention this. */
2861 logevent("AES not supported in SSH1, skipping");
2863 switch (next_cipher
) {
2864 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2865 cipher_string
= "3DES"; break;
2866 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2867 cipher_string
= "Blowfish"; break;
2868 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2869 cipher_string
= "single-DES"; break;
2871 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2875 if (!cipher_chosen
) {
2876 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2877 bombout(("Server violates SSH 1 protocol by not "
2878 "supporting 3DES encryption"));
2880 /* shouldn't happen */
2881 bombout(("No supported ciphers found"));
2885 /* Warn about chosen cipher if necessary. */
2887 sk_set_frozen(ssh
->s
, 1);
2888 askalg(ssh
->frontend
, "cipher", cipher_string
);
2889 sk_set_frozen(ssh
->s
, 0);
2893 switch (s
->cipher_type
) {
2894 case SSH_CIPHER_3DES
:
2895 logevent("Using 3DES encryption");
2897 case SSH_CIPHER_DES
:
2898 logevent("Using single-DES encryption");
2900 case SSH_CIPHER_BLOWFISH
:
2901 logevent("Using Blowfish encryption");
2905 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2906 PKT_CHAR
, s
->cipher_type
,
2907 PKT_DATA
, cookie
, 8,
2908 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2909 PKT_DATA
, s
->rsabuf
, s
->len
,
2910 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2912 logevent("Trying to enable encryption...");
2916 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2917 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2919 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2920 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2921 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2923 ssh
->crcda_ctx
= crcda_make_context();
2924 logevent("Installing CRC compensation attack detector");
2926 if (servkey
.modulus
) {
2927 sfree(servkey
.modulus
);
2928 servkey
.modulus
= NULL
;
2930 if (servkey
.exponent
) {
2931 sfree(servkey
.exponent
);
2932 servkey
.exponent
= NULL
;
2934 if (hostkey
.modulus
) {
2935 sfree(hostkey
.modulus
);
2936 hostkey
.modulus
= NULL
;
2938 if (hostkey
.exponent
) {
2939 sfree(hostkey
.exponent
);
2940 hostkey
.exponent
= NULL
;
2944 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2945 bombout(("Encryption not successfully enabled"));
2949 logevent("Successfully started encryption");
2953 if (!*ssh
->cfg
.username
) {
2954 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2955 if (!ssh_get_line("login as: ",
2956 s
->username
, sizeof(s
->username
), FALSE
)) {
2958 * get_line failed to get a username.
2961 logevent("No username provided. Abandoning session.");
2962 ssh
->close_expected
= TRUE
;
2963 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2967 int ret
; /* need not be kept over crReturn */
2968 c_write_str(ssh
, "login as: ");
2971 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2973 crWaitUntil(!pktin
);
2974 ret
= process_userpass_input(ssh
, in
, inlen
);
2978 c_write_str(ssh
, "\r\n");
2981 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2982 s
->username
[sizeof(s
->username
)-1] = '\0';
2985 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2987 char userlog
[22 + sizeof(s
->username
)];
2988 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2990 if (flags
& FLAG_INTERACTIVE
&&
2991 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2992 strcat(userlog
, "\r\n");
2993 c_write_str(ssh
, userlog
);
3000 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
3001 /* We must not attempt PK auth. Pretend we've already tried it. */
3002 s
->tried_publickey
= s
->tried_agent
= 1;
3004 s
->tried_publickey
= s
->tried_agent
= 0;
3006 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3007 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3008 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3009 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
3010 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
3011 s
->publickey_blob
= NULL
;
3013 s
->publickey_blob
= NULL
;
3015 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3016 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3018 if (agent_exists() && !s
->tried_agent
) {
3020 * Attempt RSA authentication using Pageant.
3026 logevent("Pageant is running. Requesting keys.");
3028 /* Request the keys held by the agent. */
3029 PUT_32BIT(s
->request
, 1);
3030 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3031 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3032 ssh_agent_callback
, ssh
)) {
3036 bombout(("Unexpected data from server while waiting"
3037 " for agent response"));
3040 } while (pktin
|| inlen
> 0);
3041 r
= ssh
->agent_response
;
3042 s
->responselen
= ssh
->agent_response_len
;
3044 s
->response
= (unsigned char *) r
;
3045 if (s
->response
&& s
->responselen
>= 5 &&
3046 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3047 s
->p
= s
->response
+ 5;
3048 s
->nkeys
= GET_32BIT(s
->p
);
3052 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
3055 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3058 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
3061 if (s
->publickey_blob
&&
3062 !memcmp(s
->p
, s
->publickey_blob
,
3063 s
->publickey_bloblen
)) {
3064 logevent("This key matches configured key file");
3065 s
->tried_publickey
= 1;
3070 do { /* do while (0) to make breaking easy */
3071 n
= ssh1_read_bignum
3072 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3077 n
= ssh1_read_bignum
3078 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3083 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3085 s
->commentlen
= GET_32BIT(s
->p
);
3087 if (s
->responselen
- (s
->p
-s
->response
) <
3090 s
->commentp
= (char *)s
->p
;
3091 s
->p
+= s
->commentlen
;
3095 logevent("Pageant key list packet was truncated");
3099 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3100 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3102 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3103 logevent("Key refused");
3106 logevent("Received RSA challenge");
3107 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3108 bombout(("Server's RSA challenge was badly formatted"));
3113 char *agentreq
, *q
, *ret
;
3116 len
= 1 + 4; /* message type, bit count */
3117 len
+= ssh1_bignum_length(s
->key
.exponent
);
3118 len
+= ssh1_bignum_length(s
->key
.modulus
);
3119 len
+= ssh1_bignum_length(s
->challenge
);
3120 len
+= 16; /* session id */
3121 len
+= 4; /* response format */
3122 agentreq
= snewn(4 + len
, char);
3123 PUT_32BIT(agentreq
, len
);
3125 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3126 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3128 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3129 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3130 q
+= ssh1_write_bignum(q
, s
->challenge
);
3131 memcpy(q
, s
->session_id
, 16);
3133 PUT_32BIT(q
, 1); /* response format */
3134 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3135 ssh_agent_callback
, ssh
)) {
3140 bombout(("Unexpected data from server"
3141 " while waiting for agent"
3145 } while (pktin
|| inlen
> 0);
3146 vret
= ssh
->agent_response
;
3147 retlen
= ssh
->agent_response_len
;
3152 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3153 logevent("Sending Pageant's response");
3154 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3155 PKT_DATA
, ret
+ 5, 16,
3159 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3161 ("Pageant's response accepted");
3162 if (flags
& FLAG_VERBOSE
) {
3163 c_write_str(ssh
, "Authenticated using"
3165 c_write(ssh
, s
->commentp
,
3167 c_write_str(ssh
, "\" from agent\r\n");
3172 ("Pageant's response not accepted");
3175 ("Pageant failed to answer challenge");
3179 logevent("No reply received from Pageant");
3182 freebn(s
->key
.exponent
);
3183 freebn(s
->key
.modulus
);
3184 freebn(s
->challenge
);
3193 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3194 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3196 if (ssh
->cfg
.try_tis_auth
&&
3197 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3198 !s
->tis_auth_refused
) {
3199 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3200 logevent("Requested TIS authentication");
3201 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3203 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3204 logevent("TIS authentication declined");
3205 if (flags
& FLAG_INTERACTIVE
)
3206 c_write_str(ssh
, "TIS authentication refused.\r\n");
3207 s
->tis_auth_refused
= 1;
3213 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3215 bombout(("TIS challenge packet was badly formed"));
3218 logevent("Received TIS challenge");
3219 if (challengelen
> sizeof(s
->prompt
) - 1)
3220 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3221 memcpy(s
->prompt
, challenge
, challengelen
);
3222 /* Prompt heuristic comes from OpenSSH */
3223 strncpy(s
->prompt
+ challengelen
,
3224 memchr(s
->prompt
, '\n', challengelen
) ?
3225 "": "\r\nResponse: ",
3226 (sizeof s
->prompt
) - challengelen
);
3227 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3230 if (ssh
->cfg
.try_tis_auth
&&
3231 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3232 !s
->ccard_auth_refused
) {
3233 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3234 logevent("Requested CryptoCard authentication");
3235 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3237 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3238 logevent("CryptoCard authentication declined");
3239 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3240 s
->ccard_auth_refused
= 1;
3246 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3248 bombout(("CryptoCard challenge packet was badly formed"));
3251 logevent("Received CryptoCard challenge");
3252 if (challengelen
> sizeof(s
->prompt
) - 1)
3253 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3254 memcpy(s
->prompt
, challenge
, challengelen
);
3255 strncpy(s
->prompt
+ challengelen
,
3256 memchr(s
->prompt
, '\n', challengelen
) ?
3257 "" : "\r\nResponse: ",
3258 sizeof(s
->prompt
) - challengelen
);
3259 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3262 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3263 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3264 s
->username
, ssh
->savedhost
);
3266 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3267 char *comment
= NULL
;
3270 if (flags
& FLAG_VERBOSE
)
3271 c_write_str(ssh
, "Trying public key authentication.\r\n");
3272 logeventf(ssh
, "Trying public key \"%s\"",
3273 filename_to_str(&ssh
->cfg
.keyfile
));
3274 type
= key_type(&ssh
->cfg
.keyfile
);
3275 if (type
!= SSH_KEYTYPE_SSH1
) {
3276 sprintf(msgbuf
, "Key is of wrong type (%s)",
3277 key_type_to_str(type
));
3279 c_write_str(ssh
, msgbuf
);
3280 c_write_str(ssh
, "\r\n");
3281 s
->tried_publickey
= 1;
3284 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3285 if (flags
& FLAG_VERBOSE
)
3286 c_write_str(ssh
, "No passphrase required.\r\n");
3289 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3294 * Show password prompt, having first obtained it via a TIS
3295 * or CryptoCard exchange if we're doing TIS or CryptoCard
3299 if (!ssh_get_line(s
->prompt
, s
->password
,
3300 sizeof(s
->password
), TRUE
)) {
3302 * get_line failed to get a password (for example
3303 * because one was supplied on the command line
3304 * which has already failed to work). Terminate.
3306 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3307 PKT_STR
, "No more passwords available to try",
3309 logevent("Unable to authenticate");
3310 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3311 ssh
->close_expected
= TRUE
;
3312 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3316 /* Prompt may have come from server. We've munged it a bit, so
3317 * we know it to be zero-terminated at least once. */
3318 int ret
; /* need not be saved over crReturn */
3319 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3322 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3324 crWaitUntil(!pktin
);
3325 ret
= process_userpass_input(ssh
, in
, inlen
);
3329 c_write_str(ssh
, "\r\n");
3333 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3335 * Try public key authentication with the specified
3338 s
->tried_publickey
= 1;
3341 const char *error
= NULL
;
3342 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3345 c_write_str(ssh
, "Couldn't load private key from ");
3346 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3347 c_write_str(ssh
, " (");
3348 c_write_str(ssh
, error
);
3349 c_write_str(ssh
, ").\r\n");
3350 continue; /* go and try password */
3353 c_write_str(ssh
, "Wrong passphrase.\r\n");
3354 s
->tried_publickey
= 0;
3355 continue; /* try again */
3360 * Send a public key attempt.
3362 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3363 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3366 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3367 c_write_str(ssh
, "Server refused our public key.\r\n");
3368 continue; /* go and try password */
3370 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3371 bombout(("Bizarre response to offer of public key"));
3377 unsigned char buffer
[32];
3378 Bignum challenge
, response
;
3380 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3381 bombout(("Server's RSA challenge was badly formatted"));
3384 response
= rsadecrypt(challenge
, &s
->key
);
3385 freebn(s
->key
.private_exponent
);/* burn the evidence */
3387 for (i
= 0; i
< 32; i
++) {
3388 buffer
[i
] = bignum_byte(response
, 31 - i
);
3392 MD5Update(&md5c
, buffer
, 32);
3393 MD5Update(&md5c
, s
->session_id
, 16);
3394 MD5Final(buffer
, &md5c
);
3396 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3397 PKT_DATA
, buffer
, 16, PKT_END
);
3404 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3405 if (flags
& FLAG_VERBOSE
)
3406 c_write_str(ssh
, "Failed to authenticate with"
3407 " our public key.\r\n");
3408 continue; /* go and try password */
3409 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3410 bombout(("Bizarre response to RSA authentication response"));
3414 break; /* we're through! */
3416 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3418 * Defence against traffic analysis: we send a
3419 * whole bunch of packets containing strings of
3420 * different lengths. One of these strings is the
3421 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3422 * The others are all random data in
3423 * SSH1_MSG_IGNORE packets. This way a passive
3424 * listener can't tell which is the password, and
3425 * hence can't deduce the password length.
3427 * Anybody with a password length greater than 16
3428 * bytes is going to have enough entropy in their
3429 * password that a listener won't find it _that_
3430 * much help to know how long it is. So what we'll
3433 * - if password length < 16, we send 15 packets
3434 * containing string lengths 1 through 15
3436 * - otherwise, we let N be the nearest multiple
3437 * of 8 below the password length, and send 8
3438 * packets containing string lengths N through
3439 * N+7. This won't obscure the order of
3440 * magnitude of the password length, but it will
3441 * introduce a bit of extra uncertainty.
3443 * A few servers (the old 1.2.18 through 1.2.22)
3444 * can't deal with SSH1_MSG_IGNORE. For these
3445 * servers, we need an alternative defence. We make
3446 * use of the fact that the password is interpreted
3447 * as a C string: so we can append a NUL, then some
3450 * One server (a Cisco one) can deal with neither
3451 * SSH1_MSG_IGNORE _nor_ a padded password string.
3452 * For this server we are left with no defences
3453 * against password length sniffing.
3455 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3457 * The server can deal with SSH1_MSG_IGNORE, so
3458 * we can use the primary defence.
3460 int bottom
, top
, pwlen
, i
;
3463 pwlen
= strlen(s
->password
);
3465 bottom
= 0; /* zero length passwords are OK! :-) */
3468 bottom
= pwlen
& ~7;
3472 assert(pwlen
>= bottom
&& pwlen
<= top
);
3474 randomstr
= snewn(top
+ 1, char);
3476 for (i
= bottom
; i
<= top
; i
++) {
3478 defer_packet(ssh
, s
->pwpkt_type
,
3479 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3480 PKTT_OTHER
, PKT_END
);
3482 for (j
= 0; j
< i
; j
++) {
3484 randomstr
[j
] = random_byte();
3485 } while (randomstr
[j
] == '\0');
3487 randomstr
[i
] = '\0';
3488 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3489 PKT_STR
, randomstr
, PKT_END
);
3492 logevent("Sending password with camouflage packets");
3493 ssh_pkt_defersend(ssh
);
3496 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3498 * The server can't deal with SSH1_MSG_IGNORE
3499 * but can deal with padded passwords, so we
3500 * can use the secondary defence.
3506 len
= strlen(s
->password
);
3507 if (len
< sizeof(string
)) {
3509 strcpy(string
, s
->password
);
3510 len
++; /* cover the zero byte */
3511 while (len
< sizeof(string
)) {
3512 string
[len
++] = (char) random_byte();
3517 logevent("Sending length-padded password");
3518 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3519 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3520 PKTT_OTHER
, PKT_END
);
3523 * The server has _both_
3524 * BUG_CHOKES_ON_SSH1_IGNORE and
3525 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3526 * therefore nothing we can do.
3529 len
= strlen(s
->password
);
3530 logevent("Sending unpadded password");
3531 send_packet(ssh
, s
->pwpkt_type
,
3532 PKTT_PASSWORD
, PKT_INT
, len
,
3533 PKT_DATA
, s
->password
, len
,
3534 PKTT_OTHER
, PKT_END
);
3537 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3538 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3541 logevent("Sent password");
3542 memset(s
->password
, 0, strlen(s
->password
));
3544 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3545 if (flags
& FLAG_VERBOSE
)
3546 c_write_str(ssh
, "Access denied\r\n");
3547 logevent("Authentication refused");
3548 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3549 bombout(("Strange packet received, type %d", pktin
->type
));
3554 logevent("Authentication successful");
3559 void sshfwd_close(struct ssh_channel
*c
)
3563 if (ssh
->state
!= SSH_STATE_SESSION
) {
3564 assert(ssh
->state
== SSH_STATE_CLOSED
);
3568 if (c
&& !c
->closes
) {
3570 * If halfopen is true, we have sent
3571 * CHANNEL_OPEN for this channel, but it hasn't even been
3572 * acknowledged by the server. So we must set a close flag
3573 * on it now, and then when the server acks the channel
3574 * open, we can close it then.
3577 if (ssh
->version
== 1) {
3578 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3581 struct Packet
*pktout
;
3582 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3583 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3584 ssh2_pkt_send(ssh
, pktout
);
3587 c
->closes
= 1; /* sent MSG_CLOSE */
3588 if (c
->type
== CHAN_X11
) {
3590 logevent("Forwarded X11 connection terminated");
3591 } else if (c
->type
== CHAN_SOCKDATA
||
3592 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3594 logevent("Forwarded port closed");
3599 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3603 if (ssh
->state
!= SSH_STATE_SESSION
) {
3604 assert(ssh
->state
== SSH_STATE_CLOSED
);
3608 if (ssh
->version
== 1) {
3609 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3610 PKT_INT
, c
->remoteid
,
3612 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3613 PKTT_OTHER
, PKT_END
);
3615 * In SSH1 we can return 0 here - implying that forwarded
3616 * connections are never individually throttled - because
3617 * the only circumstance that can cause throttling will be
3618 * the whole SSH connection backing up, in which case
3619 * _everything_ will be throttled as a whole.
3623 ssh2_add_channel_data(c
, buf
, len
);
3624 return ssh2_try_send(c
);
3628 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3632 if (ssh
->state
!= SSH_STATE_SESSION
) {
3633 assert(ssh
->state
== SSH_STATE_CLOSED
);
3637 if (ssh
->version
== 1) {
3638 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3639 c
->v
.v1
.throttling
= 0;
3640 ssh1_throttle(ssh
, -1);
3643 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3647 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3649 struct queued_handler
*qh
= ssh
->qhead
;
3653 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3656 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3657 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3660 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3661 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3665 ssh
->qhead
= qh
->next
;
3667 if (ssh
->qhead
->msg1
> 0) {
3668 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3669 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3671 if (ssh
->qhead
->msg2
> 0) {
3672 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3673 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3676 ssh
->qhead
= ssh
->qtail
= NULL
;
3677 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3680 qh
->handler(ssh
, pktin
, qh
->ctx
);
3685 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3686 chandler_fn_t handler
, void *ctx
)
3688 struct queued_handler
*qh
;
3690 qh
= snew(struct queued_handler
);
3693 qh
->handler
= handler
;
3697 if (ssh
->qtail
== NULL
) {
3701 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3702 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3705 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3706 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3709 ssh
->qtail
->next
= qh
;
3714 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3716 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3718 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3719 SSH2_MSG_REQUEST_SUCCESS
)) {
3720 logeventf(ssh
, "Remote port forwarding from %s enabled",
3723 logeventf(ssh
, "Remote port forwarding from %s refused",
3726 rpf
= del234(ssh
->rportfwds
, pf
);
3732 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3734 const char *portfwd_strptr
= cfg
->portfwd
;
3735 struct ssh_portfwd
*epf
;
3738 if (!ssh
->portfwds
) {
3739 ssh
->portfwds
= newtree234(ssh_portcmp
);
3742 * Go through the existing port forwardings and tag them
3743 * with status==DESTROY. Any that we want to keep will be
3744 * re-enabled (status==KEEP) as we go through the
3745 * configuration and find out which bits are the same as
3748 struct ssh_portfwd
*epf
;
3750 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3751 epf
->status
= DESTROY
;
3754 while (*portfwd_strptr
) {
3755 char address_family
, type
;
3756 int sport
,dport
,sserv
,dserv
;
3757 char sports
[256], dports
[256], saddr
[256], host
[256];
3760 address_family
= 'A';
3762 if (*portfwd_strptr
== 'A' ||
3763 *portfwd_strptr
== '4' ||
3764 *portfwd_strptr
== '6')
3765 address_family
= *portfwd_strptr
++;
3766 if (*portfwd_strptr
== 'L' ||
3767 *portfwd_strptr
== 'R' ||
3768 *portfwd_strptr
== 'D')
3769 type
= *portfwd_strptr
++;
3774 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3775 if (*portfwd_strptr
== ':') {
3777 * We've seen a colon in the middle of the
3778 * source port number. This means that
3779 * everything we've seen until now is the
3780 * source _address_, so we'll move it into
3781 * saddr and start sports from the beginning
3786 if (ssh
->version
== 1 && type
== 'R') {
3787 logeventf(ssh
, "SSH1 cannot handle remote source address "
3788 "spec \"%s\"; ignoring", sports
);
3790 strcpy(saddr
, sports
);
3793 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3797 if (*portfwd_strptr
== '\t')
3800 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3801 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3804 if (*portfwd_strptr
== ':')
3807 while (*portfwd_strptr
) {
3808 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3812 dport
= atoi(dports
);
3816 dport
= net_service_lookup(dports
);
3818 logeventf(ssh
, "Service lookup failed for destination"
3819 " port \"%s\"", dports
);
3823 while (*portfwd_strptr
) portfwd_strptr
++;
3825 portfwd_strptr
++; /* eat the NUL and move to next one */
3827 sport
= atoi(sports
);
3831 sport
= net_service_lookup(sports
);
3833 logeventf(ssh
, "Service lookup failed for source"
3834 " port \"%s\"", sports
);
3837 if (sport
&& dport
) {
3838 /* Set up a description of the source port. */
3839 struct ssh_portfwd
*pfrec
, *epfrec
;
3841 pfrec
= snew(struct ssh_portfwd
);
3843 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3844 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3845 pfrec
->sport
= sport
;
3846 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3847 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3848 pfrec
->dport
= dport
;
3849 pfrec
->local
= NULL
;
3850 pfrec
->remote
= NULL
;
3851 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3852 address_family
== '6' ? ADDRTYPE_IPV6
:
3855 epfrec
= add234(ssh
->portfwds
, pfrec
);
3856 if (epfrec
!= pfrec
) {
3858 * We already have a port forwarding with precisely
3859 * these parameters. Hence, no need to do anything;
3860 * simply tag the existing one as KEEP.
3862 epfrec
->status
= KEEP
;
3863 free_portfwd(pfrec
);
3865 pfrec
->status
= CREATE
;
3871 * Now go through and destroy any port forwardings which were
3874 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3875 if (epf
->status
== DESTROY
) {
3878 message
= dupprintf("%s port forwarding from %s%s%d",
3879 epf
->type
== 'L' ?
"local" :
3880 epf
->type
== 'R' ?
"remote" : "dynamic",
3881 epf
->saddr ? epf
->saddr
: "",
3882 epf
->saddr ?
":" : "",
3885 if (epf
->type
!= 'D') {
3886 char *msg2
= dupprintf("%s to %s:%d", message
,
3887 epf
->daddr
, epf
->dport
);
3892 logeventf(ssh
, "Cancelling %s", message
);
3896 struct ssh_rportfwd
*rpf
= epf
->remote
;
3897 struct Packet
*pktout
;
3900 * Cancel the port forwarding at the server
3903 if (ssh
->version
== 1) {
3905 * We cannot cancel listening ports on the
3906 * server side in SSH1! There's no message
3907 * to support it. Instead, we simply remove
3908 * the rportfwd record from the local end
3909 * so that any connections the server tries
3910 * to make on it are rejected.
3913 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3914 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3915 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3917 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3918 } else if (ssh
->cfg
.rport_acceptall
) {
3919 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3921 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3923 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3924 ssh2_pkt_send(ssh
, pktout
);
3927 del234(ssh
->rportfwds
, rpf
);
3929 } else if (epf
->local
) {
3930 pfd_terminate(epf
->local
);
3933 delpos234(ssh
->portfwds
, i
);
3935 i
--; /* so we don't skip one in the list */
3939 * And finally, set up any new port forwardings (status==CREATE).
3941 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3942 if (epf
->status
== CREATE
) {
3943 char *sportdesc
, *dportdesc
;
3944 sportdesc
= dupprintf("%s%s%s%s%d%s",
3945 epf
->saddr ? epf
->saddr
: "",
3946 epf
->saddr ?
":" : "",
3947 epf
->sserv ? epf
->sserv
: "",
3948 epf
->sserv ?
"(" : "",
3950 epf
->sserv ?
")" : "");
3951 if (epf
->type
== 'D') {
3954 dportdesc
= dupprintf("%s:%s%s%d%s",
3956 epf
->dserv ? epf
->dserv
: "",
3957 epf
->dserv ?
"(" : "",
3959 epf
->dserv ?
")" : "");
3962 if (epf
->type
== 'L') {
3963 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
3964 epf
->saddr
, epf
->sport
,
3967 epf
->addressfamily
);
3969 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
3970 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3971 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3972 sportdesc
, dportdesc
,
3973 err ?
" failed: " : "", err ? err
: "");
3974 } else if (epf
->type
== 'D') {
3975 const char *err
= pfd_addforward(NULL
, -1,
3976 epf
->saddr
, epf
->sport
,
3979 epf
->addressfamily
);
3981 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
3982 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3983 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3985 err ?
" failed: " : "", err ? err
: "");
3987 struct ssh_rportfwd
*pf
;
3990 * Ensure the remote port forwardings tree exists.
3992 if (!ssh
->rportfwds
) {
3993 if (ssh
->version
== 1)
3994 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3996 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3999 pf
= snew(struct ssh_rportfwd
);
4000 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
4001 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4002 pf
->dport
= epf
->dport
;
4003 pf
->sport
= epf
->sport
;
4004 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4005 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4006 epf
->daddr
, epf
->dport
);
4009 logeventf(ssh
, "Requesting remote port %s"
4010 " forward to %s", sportdesc
, dportdesc
);
4012 pf
->sportdesc
= sportdesc
;
4017 if (ssh
->version
== 1) {
4018 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4019 PKT_INT
, epf
->sport
,
4020 PKT_STR
, epf
->daddr
,
4021 PKT_INT
, epf
->dport
,
4023 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4025 ssh_rportfwd_succfail
, pf
);
4027 struct Packet
*pktout
;
4028 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4029 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4030 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4032 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4033 } else if (ssh
->cfg
.rport_acceptall
) {
4034 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4036 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4038 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4039 ssh2_pkt_send(ssh
, pktout
);
4041 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4042 SSH2_MSG_REQUEST_FAILURE
,
4043 ssh_rportfwd_succfail
, pf
);
4052 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4055 int stringlen
, bufsize
;
4057 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4058 if (string
== NULL
) {
4059 bombout(("Incoming terminal data packet was badly formed"));
4063 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4065 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4066 ssh
->v1_stdout_throttling
= 1;
4067 ssh1_throttle(ssh
, +1);
4071 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4073 /* Remote side is trying to open a channel to talk to our
4074 * X-Server. Give them back a local channel number. */
4075 struct ssh_channel
*c
;
4076 int remoteid
= ssh_pkt_getuint32(pktin
);
4078 logevent("Received X11 connect request");
4079 /* Refuse if X11 forwarding is disabled. */
4080 if (!ssh
->X11_fwd_enabled
) {
4081 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4082 PKT_INT
, remoteid
, PKT_END
);
4083 logevent("Rejected X11 connect request");
4085 c
= snew(struct ssh_channel
);
4088 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4089 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4090 logevent("Opening X11 forward connection failed");
4092 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4093 PKT_INT
, remoteid
, PKT_END
);
4096 ("Opening X11 forward connection succeeded");
4097 c
->remoteid
= remoteid
;
4098 c
->halfopen
= FALSE
;
4099 c
->localid
= alloc_channel_id(ssh
);
4101 c
->v
.v1
.throttling
= 0;
4102 c
->type
= CHAN_X11
; /* identify channel type */
4103 add234(ssh
->channels
, c
);
4104 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4105 PKT_INT
, c
->remoteid
, PKT_INT
,
4106 c
->localid
, PKT_END
);
4107 logevent("Opened X11 forward channel");
4112 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4114 /* Remote side is trying to open a channel to talk to our
4115 * agent. Give them back a local channel number. */
4116 struct ssh_channel
*c
;
4117 int remoteid
= ssh_pkt_getuint32(pktin
);
4119 /* Refuse if agent forwarding is disabled. */
4120 if (!ssh
->agentfwd_enabled
) {
4121 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4122 PKT_INT
, remoteid
, PKT_END
);
4124 c
= snew(struct ssh_channel
);
4126 c
->remoteid
= remoteid
;
4127 c
->halfopen
= FALSE
;
4128 c
->localid
= alloc_channel_id(ssh
);
4130 c
->v
.v1
.throttling
= 0;
4131 c
->type
= CHAN_AGENT
; /* identify channel type */
4132 c
->u
.a
.lensofar
= 0;
4133 add234(ssh
->channels
, c
);
4134 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4135 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4140 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4142 /* Remote side is trying to open a channel to talk to a
4143 * forwarded port. Give them back a local channel number. */
4144 struct ssh_channel
*c
;
4145 struct ssh_rportfwd pf
, *pfp
;
4148 char *host
, buf
[1024];
4150 c
= snew(struct ssh_channel
);
4153 remoteid
= ssh_pkt_getuint32(pktin
);
4154 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4155 port
= ssh_pkt_getuint32(pktin
);
4157 if (hostsize
>= lenof(pf
.dhost
))
4158 hostsize
= lenof(pf
.dhost
)-1;
4159 memcpy(pf
.dhost
, host
, hostsize
);
4160 pf
.dhost
[hostsize
] = '\0';
4162 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4165 sprintf(buf
, "Rejected remote port open request for %s:%d",
4168 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4169 PKT_INT
, remoteid
, PKT_END
);
4171 sprintf(buf
, "Received remote port open request for %s:%d",
4174 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4175 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4178 sprintf(buf
, "Port open failed: %s", e
);
4181 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4182 PKT_INT
, remoteid
, PKT_END
);
4184 c
->remoteid
= remoteid
;
4185 c
->halfopen
= FALSE
;
4186 c
->localid
= alloc_channel_id(ssh
);
4188 c
->v
.v1
.throttling
= 0;
4189 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4190 add234(ssh
->channels
, c
);
4191 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4192 PKT_INT
, c
->remoteid
, PKT_INT
,
4193 c
->localid
, PKT_END
);
4194 logevent("Forwarded port opened successfully");
4199 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4201 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4202 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4203 struct ssh_channel
*c
;
4205 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4206 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4207 c
->remoteid
= localid
;
4208 c
->halfopen
= FALSE
;
4209 c
->type
= CHAN_SOCKDATA
;
4210 c
->v
.v1
.throttling
= 0;
4211 pfd_confirm(c
->u
.pfd
.s
);
4214 if (c
&& c
->closes
) {
4216 * We have a pending close on this channel,
4217 * which we decided on before the server acked
4218 * the channel open. So now we know the
4219 * remoteid, we can close it again.
4221 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4222 PKT_INT
, c
->remoteid
, PKT_END
);
4226 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4228 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4229 struct ssh_channel
*c
;
4231 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4232 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4233 logevent("Forwarded connection refused by server");
4234 pfd_close(c
->u
.pfd
.s
);
4235 del234(ssh
->channels
, c
);
4240 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4242 /* Remote side closes a channel. */
4243 unsigned i
= ssh_pkt_getuint32(pktin
);
4244 struct ssh_channel
*c
;
4245 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4246 if (c
&& !c
->halfopen
) {
4249 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4251 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4252 logevent("Forwarded X11 connection terminated");
4253 assert(c
->u
.x11
.s
!= NULL
);
4254 x11_close(c
->u
.x11
.s
);
4257 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4258 logevent("Forwarded port closed");
4259 assert(c
->u
.pfd
.s
!= NULL
);
4260 pfd_close(c
->u
.pfd
.s
);
4264 c
->closes
|= (closetype
<< 2); /* seen this message */
4265 if (!(c
->closes
& closetype
)) {
4266 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4268 c
->closes
|= closetype
; /* sent it too */
4271 if (c
->closes
== 15) {
4272 del234(ssh
->channels
, c
);
4276 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4277 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4278 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4283 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4285 /* Data sent down one of our channels. */
4286 int i
= ssh_pkt_getuint32(pktin
);
4289 struct ssh_channel
*c
;
4291 ssh_pkt_getstring(pktin
, &p
, &len
);
4293 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4298 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4301 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4304 /* Data for an agent message. Buffer it. */
4306 if (c
->u
.a
.lensofar
< 4) {
4307 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4308 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4312 c
->u
.a
.lensofar
+= l
;
4314 if (c
->u
.a
.lensofar
== 4) {
4316 4 + GET_32BIT(c
->u
.a
.msglen
);
4317 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4319 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4321 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4323 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4325 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4329 c
->u
.a
.lensofar
+= l
;
4331 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4334 if (agent_query(c
->u
.a
.message
,
4337 ssh_agentf_callback
, c
))
4338 ssh_agentf_callback(c
, reply
, replylen
);
4339 sfree(c
->u
.a
.message
);
4340 c
->u
.a
.lensofar
= 0;
4343 bufsize
= 0; /* agent channels never back up */
4346 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4347 c
->v
.v1
.throttling
= 1;
4348 ssh1_throttle(ssh
, +1);
4353 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4356 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4357 sprintf(buf
, "Server sent command exit status %d",
4360 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4362 * In case `helpful' firewalls or proxies tack
4363 * extra human-readable text on the end of the
4364 * session which we might mistake for another
4365 * encrypted packet, we close the session once
4366 * we've sent EXIT_CONFIRMATION.
4368 ssh
->close_expected
= TRUE
;
4369 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4372 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4373 struct Packet
*pktin
)
4375 crBegin(ssh
->do_ssh1_connection_crstate
);
4377 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4378 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4379 ssh1_smsg_stdout_stderr_data
;
4381 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4382 ssh1_msg_channel_open_confirmation
;
4383 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4384 ssh1_msg_channel_open_failure
;
4385 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4386 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4387 ssh1_msg_channel_close
;
4388 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4389 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4391 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4392 logevent("Requesting agent forwarding");
4393 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4397 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4398 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4399 bombout(("Protocol confusion"));
4401 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4402 logevent("Agent forwarding refused");
4404 logevent("Agent forwarding enabled");
4405 ssh
->agentfwd_enabled
= TRUE
;
4406 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4410 if (ssh
->cfg
.x11_forward
) {
4411 char proto
[20], data
[64];
4412 logevent("Requesting X11 forwarding");
4413 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4414 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4415 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4416 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4417 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4418 PKT_STR
, proto
, PKT_STR
, data
,
4419 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4422 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4423 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4428 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4429 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4430 bombout(("Protocol confusion"));
4432 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4433 logevent("X11 forwarding refused");
4435 logevent("X11 forwarding enabled");
4436 ssh
->X11_fwd_enabled
= TRUE
;
4437 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4441 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4442 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4444 if (!ssh
->cfg
.nopty
) {
4445 /* Unpick the terminal-speed string. */
4446 /* XXX perhaps we should allow no speeds to be sent. */
4447 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4448 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4449 /* Send the pty request. */
4450 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4451 PKT_STR
, ssh
->cfg
.termtype
,
4452 PKT_INT
, ssh
->term_height
,
4453 PKT_INT
, ssh
->term_width
,
4454 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4455 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4456 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4457 PKT_CHAR
, 0, PKT_END
);
4458 ssh
->state
= SSH_STATE_INTERMED
;
4462 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4463 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4464 bombout(("Protocol confusion"));
4466 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4467 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4468 ssh
->editing
= ssh
->echoing
= 1;
4470 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4471 ssh
->ospeed
, ssh
->ispeed
);
4473 ssh
->editing
= ssh
->echoing
= 1;
4476 if (ssh
->cfg
.compression
) {
4477 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4481 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4482 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4483 bombout(("Protocol confusion"));
4485 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4486 c_write_str(ssh
, "Server refused to compress\r\n");
4488 logevent("Started compression");
4489 ssh
->v1_compressing
= TRUE
;
4490 ssh
->cs_comp_ctx
= zlib_compress_init();
4491 logevent("Initialised zlib (RFC1950) compression");
4492 ssh
->sc_comp_ctx
= zlib_decompress_init();
4493 logevent("Initialised zlib (RFC1950) decompression");
4497 * Start the shell or command.
4499 * Special case: if the first-choice command is an SSH2
4500 * subsystem (hence not usable here) and the second choice
4501 * exists, we fall straight back to that.
4504 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4506 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4507 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4508 ssh
->fallback_cmd
= TRUE
;
4511 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4513 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4514 logevent("Started session");
4517 ssh
->state
= SSH_STATE_SESSION
;
4518 if (ssh
->size_needed
)
4519 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4520 if (ssh
->eof_needed
)
4521 ssh_special(ssh
, TS_EOF
);
4524 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4526 ssh
->channels
= newtree234(ssh_channelcmp
);
4530 * By this point, most incoming packets are already being
4531 * handled by the dispatch table, and we need only pay
4532 * attention to the unusual ones.
4537 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4538 /* may be from EXEC_SHELL on some servers */
4539 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4540 /* may be from EXEC_SHELL on some servers
4541 * if no pty is available or in other odd cases. Ignore */
4543 bombout(("Strange packet received: type %d", pktin
->type
));
4548 int len
= min(inlen
, 512);
4549 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4550 PKT_INT
, len
, PKT_DATA
, in
, len
,
4551 PKTT_OTHER
, PKT_END
);
4562 * Handle the top-level SSH2 protocol.
4564 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4569 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4570 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4575 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4577 /* log reason code in disconnect message */
4581 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4582 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4585 static void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4587 /* Do nothing, because we're ignoring it! Duhh. */
4590 static void ssh1_protocol_setup(Ssh ssh
)
4595 * Most messages are handled by the coroutines.
4597 for (i
= 0; i
< 256; i
++)
4598 ssh
->packet_dispatch
[i
] = NULL
;
4601 * These special message types we install handlers for.
4603 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4604 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4605 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4608 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4609 struct Packet
*pktin
)
4611 unsigned char *in
=(unsigned char*)vin
;
4612 if (ssh
->state
== SSH_STATE_CLOSED
)
4615 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4616 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4620 if (!ssh
->protocol_initial_phase_done
) {
4621 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4622 ssh
->protocol_initial_phase_done
= TRUE
;
4627 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4631 * Utility routine for decoding comma-separated strings in KEXINIT.
4633 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4636 if (!needle
|| !haystack
) /* protect against null pointers */
4638 needlen
= strlen(needle
);
4641 * Is it at the start of the string?
4643 if (haylen
>= needlen
&& /* haystack is long enough */
4644 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4645 (haylen
== needlen
|| haystack
[needlen
] == ',')
4646 /* either , or EOS follows */
4650 * If not, search for the next comma and resume after that.
4651 * If no comma found, terminate.
4653 while (haylen
> 0 && *haystack
!= ',')
4654 haylen
--, haystack
++;
4657 haylen
--, haystack
++; /* skip over comma itself */
4662 * Similar routine for checking whether we have the first string in a list.
4664 static int first_in_commasep_string(char *needle
, char *haystack
, int haylen
)
4667 if (!needle
|| !haystack
) /* protect against null pointers */
4669 needlen
= strlen(needle
);
4671 * Is it at the start of the string?
4673 if (haylen
>= needlen
&& /* haystack is long enough */
4674 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4675 (haylen
== needlen
|| haystack
[needlen
] == ',')
4676 /* either , or EOS follows */
4684 * SSH2 key creation method.
4686 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4687 unsigned char *sessid
, char chr
,
4688 unsigned char *keyspace
)
4691 /* First 20 bytes. */
4693 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4695 SHA_Bytes(&s
, H
, 20);
4696 SHA_Bytes(&s
, &chr
, 1);
4697 SHA_Bytes(&s
, sessid
, 20);
4698 SHA_Final(&s
, keyspace
);
4699 /* Next 20 bytes. */
4701 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4703 SHA_Bytes(&s
, H
, 20);
4704 SHA_Bytes(&s
, keyspace
, 20);
4705 SHA_Final(&s
, keyspace
+ 20);
4709 * Handle the SSH2 transport layer.
4711 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
4712 struct Packet
*pktin
)
4714 unsigned char *in
= (unsigned char *)vin
;
4715 struct do_ssh2_transport_state
{
4716 int nbits
, pbits
, warn
;
4717 Bignum p
, g
, e
, f
, K
;
4718 int kex_init_value
, kex_reply_value
;
4719 const struct ssh_mac
**maclist
;
4721 const struct ssh2_cipher
*cscipher_tobe
;
4722 const struct ssh2_cipher
*sccipher_tobe
;
4723 const struct ssh_mac
*csmac_tobe
;
4724 const struct ssh_mac
*scmac_tobe
;
4725 const struct ssh_compress
*cscomp_tobe
;
4726 const struct ssh_compress
*sccomp_tobe
;
4727 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4728 int hostkeylen
, siglen
;
4729 void *hkey
; /* actual host key */
4730 unsigned char exchange_hash
[20];
4731 int n_preferred_kex
;
4732 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4733 int n_preferred_ciphers
;
4734 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4735 const struct ssh_compress
*preferred_comp
;
4736 int got_session_id
, activated_authconn
;
4737 struct Packet
*pktout
;
4739 crState(do_ssh2_transport_state
);
4741 crBegin(ssh
->do_ssh2_transport_crstate
);
4743 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4744 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4745 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4747 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4750 * Be prepared to work around the buggy MAC problem.
4752 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4753 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4755 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4758 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4760 int i
, j
, commalist_started
;
4763 * Set up the preferred key exchange. (NULL => warn below here)
4765 s
->n_preferred_kex
= 0;
4766 for (i
= 0; i
< KEX_MAX
; i
++) {
4767 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4769 s
->preferred_kex
[s
->n_preferred_kex
++] =
4770 &ssh_diffiehellman_gex
;
4773 s
->preferred_kex
[s
->n_preferred_kex
++] =
4774 &ssh_diffiehellman_group14
;
4777 s
->preferred_kex
[s
->n_preferred_kex
++] =
4778 &ssh_diffiehellman_group1
;
4781 /* Flag for later. Don't bother if it's the last in
4783 if (i
< KEX_MAX
- 1) {
4784 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4791 * Set up the preferred ciphers. (NULL => warn below here)
4793 s
->n_preferred_ciphers
= 0;
4794 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4795 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4796 case CIPHER_BLOWFISH
:
4797 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4800 if (ssh
->cfg
.ssh2_des_cbc
) {
4801 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4805 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4808 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4811 /* Flag for later. Don't bother if it's the last in
4813 if (i
< CIPHER_MAX
- 1) {
4814 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4821 * Set up preferred compression.
4823 if (ssh
->cfg
.compression
)
4824 s
->preferred_comp
= &ssh_zlib
;
4826 s
->preferred_comp
= &ssh_comp_none
;
4829 * Enable queueing of outgoing auth- or connection-layer
4830 * packets while we are in the middle of a key exchange.
4832 ssh
->queueing
= TRUE
;
4835 * Flag that KEX is in progress.
4837 ssh
->kex_in_progress
= TRUE
;
4840 * Construct and send our key exchange packet.
4842 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4843 for (i
= 0; i
< 16; i
++)
4844 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4845 /* List key exchange algorithms. */
4846 ssh2_pkt_addstring_start(s
->pktout
);
4847 commalist_started
= 0;
4848 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4849 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4850 if (!k
) continue; /* warning flag */
4851 if (commalist_started
)
4852 ssh2_pkt_addstring_str(s
->pktout
, ",");
4853 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4854 commalist_started
= 1;
4856 /* List server host key algorithms. */
4857 ssh2_pkt_addstring_start(s
->pktout
);
4858 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4859 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4860 if (i
< lenof(hostkey_algs
) - 1)
4861 ssh2_pkt_addstring_str(s
->pktout
, ",");
4863 /* List client->server encryption algorithms. */
4864 ssh2_pkt_addstring_start(s
->pktout
);
4865 commalist_started
= 0;
4866 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4867 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4868 if (!c
) continue; /* warning flag */
4869 for (j
= 0; j
< c
->nciphers
; j
++) {
4870 if (commalist_started
)
4871 ssh2_pkt_addstring_str(s
->pktout
, ",");
4872 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4873 commalist_started
= 1;
4876 /* List server->client encryption algorithms. */
4877 ssh2_pkt_addstring_start(s
->pktout
);
4878 commalist_started
= 0;
4879 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4880 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4881 if (!c
) continue; /* warning flag */
4882 for (j
= 0; j
< c
->nciphers
; j
++) {
4883 if (commalist_started
)
4884 ssh2_pkt_addstring_str(s
->pktout
, ",");
4885 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4886 commalist_started
= 1;
4889 /* List client->server MAC algorithms. */
4890 ssh2_pkt_addstring_start(s
->pktout
);
4891 for (i
= 0; i
< s
->nmacs
; i
++) {
4892 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4893 if (i
< s
->nmacs
- 1)
4894 ssh2_pkt_addstring_str(s
->pktout
, ",");
4896 /* List server->client MAC algorithms. */
4897 ssh2_pkt_addstring_start(s
->pktout
);
4898 for (i
= 0; i
< s
->nmacs
; i
++) {
4899 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4900 if (i
< s
->nmacs
- 1)
4901 ssh2_pkt_addstring_str(s
->pktout
, ",");
4903 /* List client->server compression algorithms. */
4904 ssh2_pkt_addstring_start(s
->pktout
);
4905 assert(lenof(compressions
) > 1);
4906 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4907 for (i
= 0; i
< lenof(compressions
); i
++) {
4908 const struct ssh_compress
*c
= compressions
[i
];
4909 if (c
!= s
->preferred_comp
) {
4910 ssh2_pkt_addstring_str(s
->pktout
, ",");
4911 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4914 /* List server->client compression algorithms. */
4915 ssh2_pkt_addstring_start(s
->pktout
);
4916 assert(lenof(compressions
) > 1);
4917 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4918 for (i
= 0; i
< lenof(compressions
); i
++) {
4919 const struct ssh_compress
*c
= compressions
[i
];
4920 if (c
!= s
->preferred_comp
) {
4921 ssh2_pkt_addstring_str(s
->pktout
, ",");
4922 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4925 /* List client->server languages. Empty list. */
4926 ssh2_pkt_addstring_start(s
->pktout
);
4927 /* List server->client languages. Empty list. */
4928 ssh2_pkt_addstring_start(s
->pktout
);
4929 /* First KEX packet does _not_ follow, because we're not that brave. */
4930 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4932 ssh2_pkt_adduint32(s
->pktout
, 0);
4935 ssh
->exhash
= ssh
->exhashbase
;
4936 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4938 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4942 if (pktin
->length
> 5)
4943 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4946 * Now examine the other side's KEXINIT to see what we're up
4951 int i
, j
, len
, guessok
;
4953 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4954 bombout(("expected key exchange packet from server"));
4958 ssh
->hostkey
= NULL
;
4959 s
->cscipher_tobe
= NULL
;
4960 s
->sccipher_tobe
= NULL
;
4961 s
->csmac_tobe
= NULL
;
4962 s
->scmac_tobe
= NULL
;
4963 s
->cscomp_tobe
= NULL
;
4964 s
->sccomp_tobe
= NULL
;
4965 pktin
->savedpos
+= 16; /* skip garbage cookie */
4966 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4968 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4969 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4972 } else if (in_commasep_string(k
->name
, str
, len
)) {
4977 sk_set_frozen(ssh
->s
, 1);
4978 askalg(ssh
->frontend
, "key-exchange algorithm",
4980 sk_set_frozen(ssh
->s
, 0);
4986 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4987 str ? str
: "(null)"));
4991 * Note that the server's guess is considered wrong if it doesn't match
4992 * the first algorithm in our list, even if it's still the algorithm
4996 first_in_commasep_string(s
->preferred_kex
[0]->name
, str
, len
);
4997 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4998 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4999 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
5000 ssh
->hostkey
= hostkey_algs
[i
];
5004 guessok
= guessok
&&
5005 first_in_commasep_string(hostkey_algs
[0]->name
, str
, len
);
5006 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
5008 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5009 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5013 for (j
= 0; j
< c
->nciphers
; j
++) {
5014 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5015 s
->cscipher_tobe
= c
->list
[j
];
5020 if (s
->cscipher_tobe
) {
5022 sk_set_frozen(ssh
->s
, 1);
5023 askalg(ssh
->frontend
, "client-to-server cipher",
5024 s
->cscipher_tobe
->name
);
5025 sk_set_frozen(ssh
->s
, 0);
5030 if (!s
->cscipher_tobe
) {
5031 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5032 str ? str
: "(null)"));
5036 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5038 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5039 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5043 for (j
= 0; j
< c
->nciphers
; j
++) {
5044 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5045 s
->sccipher_tobe
= c
->list
[j
];
5050 if (s
->sccipher_tobe
) {
5052 sk_set_frozen(ssh
->s
, 1);
5053 askalg(ssh
->frontend
, "server-to-client cipher",
5054 s
->sccipher_tobe
->name
);
5055 sk_set_frozen(ssh
->s
, 0);
5060 if (!s
->sccipher_tobe
) {
5061 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5062 str ? str
: "(null)"));
5066 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5067 for (i
= 0; i
< s
->nmacs
; i
++) {
5068 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5069 s
->csmac_tobe
= s
->maclist
[i
];
5073 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5074 for (i
= 0; i
< s
->nmacs
; i
++) {
5075 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5076 s
->scmac_tobe
= s
->maclist
[i
];
5080 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5081 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5082 const struct ssh_compress
*c
=
5083 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5084 if (in_commasep_string(c
->name
, str
, len
)) {
5089 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5090 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5091 const struct ssh_compress
*c
=
5092 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5093 if (in_commasep_string(c
->name
, str
, len
)) {
5098 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server language */
5099 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client language */
5100 if (ssh2_pkt_getbool(pktin
) && !guessok
) /* first_kex_packet_follows */
5101 crWaitUntil(pktin
); /* Ignore packet */
5105 * Work out the number of bits of key we will need from the key
5106 * exchange. We start with the maximum key length of either
5112 csbits
= s
->cscipher_tobe
->keylen
;
5113 scbits
= s
->sccipher_tobe
->keylen
;
5114 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5116 /* The keys only have 160-bit entropy, since they're based on
5117 * a SHA-1 hash. So cap the key size at 160 bits. */
5122 * If we're doing Diffie-Hellman group exchange, start by
5123 * requesting a group.
5125 if (!ssh
->kex
->pdata
) {
5126 logevent("Doing Diffie-Hellman group exchange");
5127 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5129 * Work out how big a DH group we will need to allow that
5132 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5133 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5134 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5135 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5138 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5139 bombout(("expected key exchange group packet from server"));
5142 s
->p
= ssh2_pkt_getmp(pktin
);
5143 s
->g
= ssh2_pkt_getmp(pktin
);
5144 if (!s
->p
|| !s
->g
) {
5145 bombout(("unable to read mp-ints from incoming group packet"));
5148 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5149 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5150 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5152 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5153 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5154 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5155 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5156 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5157 ssh
->kex
->groupname
);
5160 logevent("Doing Diffie-Hellman key exchange");
5162 * Now generate and send e for Diffie-Hellman.
5164 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5165 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5166 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5167 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5170 if (pktin
->type
!= s
->kex_reply_value
) {
5171 bombout(("expected key exchange reply packet from server"));
5174 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5175 s
->f
= ssh2_pkt_getmp(pktin
);
5177 bombout(("unable to parse key exchange reply packet"));
5180 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5182 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5184 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5185 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5186 sha_uint32(&ssh
->exhash
, s
->pbits
);
5187 sha_mpint(&ssh
->exhash
, s
->p
);
5188 sha_mpint(&ssh
->exhash
, s
->g
);
5190 sha_mpint(&ssh
->exhash
, s
->e
);
5191 sha_mpint(&ssh
->exhash
, s
->f
);
5192 sha_mpint(&ssh
->exhash
, s
->K
);
5193 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5195 dh_cleanup(ssh
->kex_ctx
);
5196 ssh
->kex_ctx
= NULL
;
5199 debug(("Exchange hash is:\n"));
5200 dmemdump(s
->exchange_hash
, 20);
5203 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5205 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5206 (char *)s
->exchange_hash
, 20)) {
5207 bombout(("Server's host key did not match the signature supplied"));
5212 * Authenticate remote host: verify host key. (We've already
5213 * checked the signature of the exchange hash.)
5215 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5216 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5217 sk_set_frozen(ssh
->s
, 1);
5218 verify_ssh_host_key(ssh
->frontend
,
5219 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5220 s
->keystr
, s
->fingerprint
);
5221 sk_set_frozen(ssh
->s
, 0);
5222 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5223 logevent("Host key fingerprint is:");
5224 logevent(s
->fingerprint
);
5226 sfree(s
->fingerprint
);
5228 ssh
->hostkey
->freekey(s
->hkey
);
5231 * The exchange hash from the very first key exchange is also
5232 * the session id, used in session key construction and
5235 if (!s
->got_session_id
) {
5236 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5237 sizeof(s
->exchange_hash
));
5238 s
->got_session_id
= TRUE
;
5242 * Send SSH2_MSG_NEWKEYS.
5244 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5245 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5246 ssh
->outgoing_data_size
= 0; /* start counting from here */
5249 * We've sent client NEWKEYS, so create and initialise
5250 * client-to-server session keys.
5252 if (ssh
->cs_cipher_ctx
)
5253 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5254 ssh
->cscipher
= s
->cscipher_tobe
;
5255 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5257 if (ssh
->cs_mac_ctx
)
5258 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5259 ssh
->csmac
= s
->csmac_tobe
;
5260 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5262 if (ssh
->cs_comp_ctx
)
5263 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5264 ssh
->cscomp
= s
->cscomp_tobe
;
5265 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5268 * Set IVs on client-to-server keys. Here we use the exchange
5269 * hash from the _first_ key exchange.
5272 unsigned char keyspace
[40];
5273 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5274 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5275 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5276 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5277 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5278 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5281 logeventf(ssh
, "Initialised %.200s client->server encryption",
5282 ssh
->cscipher
->text_name
);
5283 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5284 ssh
->csmac
->text_name
);
5285 if (ssh
->cscomp
->text_name
)
5286 logeventf(ssh
, "Initialised %s compression",
5287 ssh
->cscomp
->text_name
);
5290 * Now our end of the key exchange is complete, we can send all
5291 * our queued higher-layer packets.
5293 ssh
->queueing
= FALSE
;
5294 ssh2_pkt_queuesend(ssh
);
5297 * Expect SSH2_MSG_NEWKEYS from server.
5300 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5301 bombout(("expected new-keys packet from server"));
5304 ssh
->incoming_data_size
= 0; /* start counting from here */
5307 * We've seen server NEWKEYS, so create and initialise
5308 * server-to-client session keys.
5310 if (ssh
->sc_cipher_ctx
)
5311 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5312 ssh
->sccipher
= s
->sccipher_tobe
;
5313 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5315 if (ssh
->sc_mac_ctx
)
5316 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5317 ssh
->scmac
= s
->scmac_tobe
;
5318 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5320 if (ssh
->sc_comp_ctx
)
5321 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5322 ssh
->sccomp
= s
->sccomp_tobe
;
5323 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5326 * Set IVs on server-to-client keys. Here we use the exchange
5327 * hash from the _first_ key exchange.
5330 unsigned char keyspace
[40];
5331 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5332 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5333 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5334 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5335 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5336 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5338 logeventf(ssh
, "Initialised %.200s server->client encryption",
5339 ssh
->sccipher
->text_name
);
5340 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5341 ssh
->scmac
->text_name
);
5342 if (ssh
->sccomp
->text_name
)
5343 logeventf(ssh
, "Initialised %s decompression",
5344 ssh
->sccomp
->text_name
);
5347 * Free key exchange data.
5351 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5357 * Key exchange is over. Loop straight back round if we have a
5358 * deferred rekey reason.
5360 if (ssh
->deferred_rekey_reason
) {
5361 logevent(ssh
->deferred_rekey_reason
);
5363 ssh
->deferred_rekey_reason
= NULL
;
5364 goto begin_key_exchange
;
5368 * Otherwise, schedule a timer for our next rekey.
5370 ssh
->kex_in_progress
= FALSE
;
5371 ssh
->last_rekey
= GETTICKCOUNT();
5372 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5373 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5377 * If this is the first key exchange phase, we must pass the
5378 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5379 * wants to see it but because it will need time to initialise
5380 * itself before it sees an actual packet. In subsequent key
5381 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5382 * it would only confuse the layer above.
5384 if (s
->activated_authconn
) {
5387 s
->activated_authconn
= TRUE
;
5390 * Now we're encrypting. Begin returning 1 to the protocol main
5391 * function so that other things can run on top of the
5392 * transport. If we ever see a KEXINIT, we must go back to the
5395 * We _also_ go back to the start if we see pktin==NULL and
5396 * inlen==-1, because this is a special signal meaning
5397 * `initiate client-driven rekey', and `in' contains a message
5398 * giving the reason for the rekey.
5400 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5401 (!pktin
&& inlen
== -1))) {
5406 logevent("Server initiated key re-exchange");
5409 * Special case: if the server bug is set that doesn't
5410 * allow rekeying, we give a different log message and
5411 * continue waiting. (If such a server _initiates_ a rekey,
5412 * we process it anyway!)
5414 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5415 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5417 /* Reset the counters, so that at least this message doesn't
5418 * hit the event log _too_ often. */
5419 ssh
->outgoing_data_size
= 0;
5420 ssh
->incoming_data_size
= 0;
5421 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5423 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5426 goto wait_for_rekey
; /* this is utterly horrid */
5428 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5431 goto begin_key_exchange
;
5437 * Add data to an SSH2 channel output buffer.
5439 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5442 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5446 * Attempt to send data on an SSH2 channel.
5448 static int ssh2_try_send(struct ssh_channel
*c
)
5451 struct Packet
*pktout
;
5453 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5456 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5457 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5458 len
= c
->v
.v2
.remwindow
;
5459 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5460 len
= c
->v
.v2
.remmaxpkt
;
5461 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5462 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5463 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5464 ssh2_pkt_addstring_start(pktout
);
5465 ssh2_pkt_addstring_data(pktout
, data
, len
);
5466 end_log_omission(ssh
, pktout
);
5467 ssh2_pkt_send(ssh
, pktout
);
5468 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5469 c
->v
.v2
.remwindow
-= len
;
5473 * After having sent as much data as we can, return the amount
5476 return bufchain_size(&c
->v
.v2
.outbuffer
);
5480 * Potentially enlarge the window on an SSH2 channel.
5482 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5487 * Never send WINDOW_ADJUST for a channel that the remote side
5488 * already thinks it's closed; there's no point, since it won't
5489 * be sending any more data anyway.
5495 * Only send a WINDOW_ADJUST if there's significantly more window
5496 * available than the other end thinks there is. This saves us
5497 * sending a WINDOW_ADJUST for every character in a shell session.
5499 * "Significant" is arbitrarily defined as half the window size.
5501 if (newwin
> c
->v
.v2
.locwindow
* 2) {
5502 struct Packet
*pktout
;
5504 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5505 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5506 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5507 ssh2_pkt_send(ssh
, pktout
);
5508 c
->v
.v2
.locwindow
= newwin
;
5512 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5514 unsigned i
= ssh_pkt_getuint32(pktin
);
5515 struct ssh_channel
*c
;
5516 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5517 if (c
&& !c
->closes
)
5518 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5521 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5525 unsigned i
= ssh_pkt_getuint32(pktin
);
5526 struct ssh_channel
*c
;
5527 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5529 return; /* nonexistent channel */
5530 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5531 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5532 return; /* extended but not stderr */
5533 ssh_pkt_getstring(pktin
, &data
, &length
);
5536 c
->v
.v2
.locwindow
-= length
;
5538 case CHAN_MAINSESSION
:
5540 from_backend(ssh
->frontend
, pktin
->type
==
5541 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5545 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5548 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5551 while (length
> 0) {
5552 if (c
->u
.a
.lensofar
< 4) {
5553 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5554 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5558 c
->u
.a
.lensofar
+= l
;
5560 if (c
->u
.a
.lensofar
== 4) {
5562 4 + GET_32BIT(c
->u
.a
.msglen
);
5563 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5565 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5567 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5569 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5571 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5575 c
->u
.a
.lensofar
+= l
;
5577 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5580 if (agent_query(c
->u
.a
.message
,
5583 ssh_agentf_callback
, c
))
5584 ssh_agentf_callback(c
, reply
, replylen
);
5585 sfree(c
->u
.a
.message
);
5586 c
->u
.a
.lensofar
= 0;
5593 * If we are not buffering too much data,
5594 * enlarge the window again at the remote side.
5596 if (bufsize
< OUR_V2_WINSIZE
)
5597 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5601 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5603 unsigned i
= ssh_pkt_getuint32(pktin
);
5604 struct ssh_channel
*c
;
5606 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5608 return; /* nonexistent channel */
5610 if (c
->type
== CHAN_X11
) {
5612 * Remote EOF on an X11 channel means we should
5613 * wrap up and close the channel ourselves.
5615 x11_close(c
->u
.x11
.s
);
5617 } else if (c
->type
== CHAN_AGENT
) {
5619 } else if (c
->type
== CHAN_SOCKDATA
) {
5620 pfd_close(c
->u
.pfd
.s
);
5625 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5627 unsigned i
= ssh_pkt_getuint32(pktin
);
5628 struct ssh_channel
*c
;
5629 struct Packet
*pktout
;
5631 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5632 if (!c
|| c
->halfopen
) {
5633 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5634 c ?
"half-open" : "nonexistent", i
));
5637 /* Do pre-close processing on the channel. */
5639 case CHAN_MAINSESSION
:
5640 ssh
->mainchan
= NULL
;
5641 update_specials_menu(ssh
->frontend
);
5644 if (c
->u
.x11
.s
!= NULL
)
5645 x11_close(c
->u
.x11
.s
);
5652 if (c
->u
.pfd
.s
!= NULL
)
5653 pfd_close(c
->u
.pfd
.s
);
5657 if (c
->closes
== 0) {
5658 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5659 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5660 ssh2_pkt_send(ssh
, pktout
);
5662 del234(ssh
->channels
, c
);
5663 bufchain_clear(&c
->v
.v2
.outbuffer
);
5667 * See if that was the last channel left open.
5668 * (This is only our termination condition if we're
5669 * not running in -N mode.)
5671 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5672 logevent("All channels closed. Disconnecting");
5675 * We used to send SSH_MSG_DISCONNECT here,
5676 * because I'd believed that _every_ conforming
5677 * SSH2 connection had to end with a disconnect
5678 * being sent by at least one side; apparently
5679 * I was wrong and it's perfectly OK to
5680 * unceremoniously slam the connection shut
5681 * when you're done, and indeed OpenSSH feels
5682 * this is more polite than sending a
5683 * DISCONNECT. So now we don't.
5685 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5686 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5687 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5688 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5689 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5691 ssh
->close_expected
= TRUE
;
5692 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5696 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5698 unsigned i
= ssh_pkt_getuint32(pktin
);
5699 struct ssh_channel
*c
;
5700 struct Packet
*pktout
;
5702 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5704 return; /* nonexistent channel */
5705 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5706 return; /* dunno why they're confirming this */
5707 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5708 c
->halfopen
= FALSE
;
5709 c
->type
= CHAN_SOCKDATA
;
5710 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5711 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5713 pfd_confirm(c
->u
.pfd
.s
);
5716 * We have a pending close on this channel,
5717 * which we decided on before the server acked
5718 * the channel open. So now we know the
5719 * remoteid, we can close it again.
5721 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5722 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5723 ssh2_pkt_send(ssh
, pktout
);
5727 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5729 static const char *const reasons
[] = {
5730 "<unknown reason code>",
5731 "Administratively prohibited",
5733 "Unknown channel type",
5734 "Resource shortage",
5736 unsigned i
= ssh_pkt_getuint32(pktin
);
5737 unsigned reason_code
;
5738 char *reason_string
;
5741 struct ssh_channel
*c
;
5742 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5744 return; /* nonexistent channel */
5745 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5746 return; /* dunno why they're failing this */
5748 reason_code
= ssh_pkt_getuint32(pktin
);
5749 if (reason_code
>= lenof(reasons
))
5750 reason_code
= 0; /* ensure reasons[reason_code] in range */
5751 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5752 message
= dupprintf("Forwarded connection refused by"
5753 " server: %s [%.*s]", reasons
[reason_code
],
5754 reason_length
, reason_string
);
5758 pfd_close(c
->u
.pfd
.s
);
5760 del234(ssh
->channels
, c
);
5764 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5768 int typelen
, want_reply
;
5769 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5770 struct ssh_channel
*c
;
5771 struct Packet
*pktout
;
5773 localid
= ssh_pkt_getuint32(pktin
);
5774 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5775 want_reply
= ssh2_pkt_getbool(pktin
);
5778 * First, check that the channel exists. Otherwise,
5779 * we can instantly disconnect with a rude message.
5781 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5784 sprintf(buf
, "Received channel request for nonexistent"
5785 " channel %d", localid
);
5787 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5788 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5789 ssh2_pkt_addstring(pktout
, buf
);
5790 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5791 ssh2_pkt_send_noqueue(ssh
, pktout
);
5792 connection_fatal(ssh
->frontend
, "%s", buf
);
5793 ssh
->close_expected
= TRUE
;
5794 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5799 * Having got the channel number, we now look at
5800 * the request type string to see if it's something
5803 if (c
== ssh
->mainchan
) {
5805 * We recognise "exit-status" and "exit-signal" on
5806 * the primary channel.
5808 if (typelen
== 11 &&
5809 !memcmp(type
, "exit-status", 11)) {
5811 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5812 logeventf(ssh
, "Server sent command exit status %d",
5814 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5816 } else if (typelen
== 11 &&
5817 !memcmp(type
, "exit-signal", 11)) {
5819 int is_plausible
= TRUE
, is_int
= FALSE
;
5820 char *fmt_sig
= "", *fmt_msg
= "";
5822 int msglen
= 0, core
= FALSE
;
5823 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5824 * provide an `int' for the signal, despite its
5825 * having been a `string' in the drafts since at
5826 * least 2001. (Fixed in session.c 1.147.) Try to
5827 * infer which we can safely parse it as. */
5829 unsigned char *p
= pktin
->body
+
5831 long len
= pktin
->length
- pktin
->savedpos
;
5832 unsigned long num
= GET_32BIT(p
); /* what is it? */
5833 /* If it's 0, it hardly matters; assume string */
5837 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5838 #define CHECK_HYPOTHESIS(offset, result) \
5841 if (q >= 0 && q+4 <= len) { \
5842 q = q + 4 + GET_32BIT(p+q); \
5843 if (q >= 0 && q+4 <= len && \
5844 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
5848 CHECK_HYPOTHESIS(4+1, maybe_int
);
5849 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5850 #undef CHECK_HYPOTHESIS
5851 if (maybe_int
&& !maybe_str
)
5853 else if (!maybe_int
&& maybe_str
)
5856 /* Crikey. Either or neither. Panic. */
5857 is_plausible
= FALSE
;
5862 /* Old non-standard OpenSSH. */
5863 int signum
= ssh_pkt_getuint32(pktin
);
5864 fmt_sig
= dupprintf(" %d", signum
);
5866 /* As per the drafts. */
5869 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5870 /* Signal name isn't supposed to be blank, but
5871 * let's cope gracefully if it is. */
5873 fmt_sig
= dupprintf(" \"%.*s\"",
5877 core
= ssh2_pkt_getbool(pktin
);
5878 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5880 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5882 /* ignore lang tag */
5883 } /* else don't attempt to parse */
5884 logeventf(ssh
, "Server exited on signal%s%s%s",
5885 fmt_sig
, core ?
" (core dumped)" : "",
5887 if (*fmt_sig
) sfree(fmt_sig
);
5888 if (*fmt_msg
) sfree(fmt_msg
);
5889 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5894 * This is a channel request we don't know
5895 * about, so we now either ignore the request
5896 * or respond with CHANNEL_FAILURE, depending
5899 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5902 pktout
= ssh2_pkt_init(reply
);
5903 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5904 ssh2_pkt_send(ssh
, pktout
);
5908 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5911 int typelen
, want_reply
;
5912 struct Packet
*pktout
;
5914 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5915 want_reply
= ssh2_pkt_getbool(pktin
);
5918 * We currently don't support any global requests
5919 * at all, so we either ignore the request or
5920 * respond with REQUEST_FAILURE, depending on
5924 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5925 ssh2_pkt_send(ssh
, pktout
);
5929 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5937 struct ssh_channel
*c
;
5938 unsigned remid
, winsize
, pktsize
;
5939 struct Packet
*pktout
;
5941 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5942 c
= snew(struct ssh_channel
);
5945 remid
= ssh_pkt_getuint32(pktin
);
5946 winsize
= ssh_pkt_getuint32(pktin
);
5947 pktsize
= ssh_pkt_getuint32(pktin
);
5949 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5952 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5953 addrstr
= snewn(peeraddrlen
+1, char);
5954 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5955 addrstr
[peeraddrlen
] = '\0';
5956 peerport
= ssh_pkt_getuint32(pktin
);
5958 logeventf(ssh
, "Received X11 connect request from %s:%d",
5961 if (!ssh
->X11_fwd_enabled
)
5962 error
= "X11 forwarding is not enabled";
5963 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5964 ssh
->x11auth
, addrstr
, peerport
,
5965 &ssh
->cfg
) != NULL
) {
5966 error
= "Unable to open an X11 connection";
5968 logevent("Opening X11 forward connection succeeded");
5973 } else if (typelen
== 15 &&
5974 !memcmp(type
, "forwarded-tcpip", 15)) {
5975 struct ssh_rportfwd pf
, *realpf
;
5978 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5979 pf
.sport
= ssh_pkt_getuint32(pktin
);
5980 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5981 peerport
= ssh_pkt_getuint32(pktin
);
5982 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5983 logeventf(ssh
, "Received remote port %d open request "
5984 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5985 if (realpf
== NULL
) {
5986 error
= "Remote port is not recognised";
5988 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5992 realpf
->pfrec
->addressfamily
);
5993 logeventf(ssh
, "Attempting to forward remote port to "
5994 "%s:%d", realpf
->dhost
, realpf
->dport
);
5996 logeventf(ssh
, "Port open failed: %s", e
);
5997 error
= "Port open failed";
5999 logevent("Forwarded port opened successfully");
6000 c
->type
= CHAN_SOCKDATA
;
6003 } else if (typelen
== 22 &&
6004 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6005 if (!ssh
->agentfwd_enabled
)
6006 error
= "Agent forwarding is not enabled";
6008 c
->type
= CHAN_AGENT
; /* identify channel type */
6009 c
->u
.a
.lensofar
= 0;
6012 error
= "Unsupported channel type requested";
6015 c
->remoteid
= remid
;
6016 c
->halfopen
= FALSE
;
6018 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6019 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6020 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
6021 ssh2_pkt_addstring(pktout
, error
);
6022 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6023 ssh2_pkt_send(ssh
, pktout
);
6024 logeventf(ssh
, "Rejected channel open: %s", error
);
6027 c
->localid
= alloc_channel_id(ssh
);
6029 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6030 c
->v
.v2
.remwindow
= winsize
;
6031 c
->v
.v2
.remmaxpkt
= pktsize
;
6032 bufchain_init(&c
->v
.v2
.outbuffer
);
6033 add234(ssh
->channels
, c
);
6034 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6035 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6036 ssh2_pkt_adduint32(pktout
, c
->localid
);
6037 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
6038 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6039 ssh2_pkt_send(ssh
, pktout
);
6044 * Handle the SSH2 userauth and connection layers.
6046 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6047 struct Packet
*pktin
)
6049 struct do_ssh2_authconn_state
{
6051 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
6053 AUTH_KEYBOARD_INTERACTIVE
6057 AUTH_TYPE_PUBLICKEY
,
6058 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6059 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6061 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6062 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6064 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6065 int tried_pubkey_config
, tried_agent
;
6066 int kbd_inter_running
, kbd_inter_refused
;
6068 int num_prompts
, curr_prompt
, echo
;
6073 void *publickey_blob
;
6074 int publickey_bloblen
;
6075 unsigned char request
[5], *response
, *p
;
6079 char *pkblob
, *alg
, *commentp
;
6080 int pklen
, alglen
, commentlen
;
6081 int siglen
, retlen
, len
;
6082 char *q
, *agentreq
, *ret
;
6084 int num_env
, env_left
, env_ok
;
6085 struct Packet
*pktout
;
6087 crState(do_ssh2_authconn_state
);
6089 crBegin(ssh
->do_ssh2_authconn_crstate
);
6092 * Request userauth protocol, and await a response to it.
6094 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6095 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6096 ssh2_pkt_send(ssh
, s
->pktout
);
6097 crWaitUntilV(pktin
);
6098 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6099 bombout(("Server refused user authentication protocol"));
6104 * We repeat this whole loop, including the username prompt,
6105 * until we manage a successful authentication. If the user
6106 * types the wrong _password_, they can be sent back to the
6107 * beginning to try another username, if this is configured on.
6108 * (If they specify a username in the config, they are never
6109 * asked, even if they do give a wrong password.)
6111 * I think this best serves the needs of
6113 * - the people who have no configuration, no keys, and just
6114 * want to try repeated (username,password) pairs until they
6115 * type both correctly
6117 * - people who have keys and configuration but occasionally
6118 * need to fall back to passwords
6120 * - people with a key held in Pageant, who might not have
6121 * logged in to a particular machine before; so they want to
6122 * type a username, and then _either_ their key will be
6123 * accepted, _or_ they will type a password. If they mistype
6124 * the username they will want to be able to get back and
6127 s
->username
[0] = '\0';
6128 s
->got_username
= FALSE
;
6133 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6135 * We got a username last time round this loop, and
6136 * with change_username turned off we don't try to get
6139 } else if (!*ssh
->cfg
.username
) {
6140 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6141 if (!ssh_get_line("login as: ",
6142 s
->username
, sizeof(s
->username
), FALSE
)) {
6144 * get_line failed to get a username.
6147 logevent("No username provided. Abandoning session.");
6148 ssh
->close_expected
= TRUE
;
6149 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6153 int ret
; /* need not be saved across crReturn */
6154 c_write_str(ssh
, "login as: ");
6156 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6158 crWaitUntilV(!pktin
);
6159 ret
= process_userpass_input(ssh
, in
, inlen
);
6163 c_write_str(ssh
, "\r\n");
6165 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6168 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6169 s
->username
[sizeof(s
->username
)-1] = '\0';
6170 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6171 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6172 c_write_str(ssh
, stuff
);
6176 s
->got_username
= TRUE
;
6179 * Send an authentication request using method "none": (a)
6180 * just in case it succeeds, and (b) so that we know what
6181 * authentication methods we can usefully try next.
6183 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6185 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6186 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6187 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6188 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6189 ssh2_pkt_send(ssh
, s
->pktout
);
6190 s
->type
= AUTH_TYPE_NONE
;
6192 s
->we_are_in
= FALSE
;
6194 s
->tried_pubkey_config
= FALSE
;
6195 s
->tried_agent
= FALSE
;
6196 s
->kbd_inter_running
= FALSE
;
6197 s
->kbd_inter_refused
= FALSE
;
6198 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6199 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6201 logeventf(ssh
, "Reading private key file \"%.150s\"",
6202 filename_to_str(&ssh
->cfg
.keyfile
));
6203 keytype
= key_type(&ssh
->cfg
.keyfile
);
6204 if (keytype
== SSH_KEYTYPE_SSH2
) {
6206 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6207 &s
->publickey_bloblen
, NULL
);
6210 logeventf(ssh
, "Unable to use this key file (%s)",
6211 key_type_to_str(keytype
));
6212 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6214 filename_to_str(&ssh
->cfg
.keyfile
),
6215 key_type_to_str(keytype
));
6216 c_write_str(ssh
, msgbuf
);
6218 s
->publickey_blob
= NULL
;
6221 s
->publickey_blob
= NULL
;
6225 * Wait for the result of the last authentication request.
6228 crWaitUntilV(pktin
);
6229 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6233 * Don't show the banner if we're operating in
6234 * non-verbose non-interactive mode. (It's probably
6235 * a script, which means nobody will read the
6236 * banner _anyway_, and moreover the printing of
6237 * the banner will screw up processing on the
6238 * output of (say) plink.)
6240 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6241 ssh_pkt_getstring(pktin
, &banner
, &size
);
6243 c_write_untrusted(ssh
, banner
, size
);
6245 crWaitUntilV(pktin
);
6247 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6248 logevent("Access granted");
6249 s
->we_are_in
= TRUE
;
6253 if (s
->kbd_inter_running
&&
6254 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6256 * This is either a further set-of-prompts packet
6257 * in keyboard-interactive authentication, or it's
6258 * the same one and we came back here with `gotit'
6259 * set. In the former case, we must reset the
6260 * curr_prompt variable.
6264 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6265 /* FIXME: perhaps we should support this? */
6266 bombout(("PASSWD_CHANGEREQ not yet supported"));
6268 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6269 bombout(("Strange packet received during authentication: type %d",
6277 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6278 * we can look at the string in it and know what we can
6279 * helpfully try next.
6281 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6284 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6285 s
->kbd_inter_running
= FALSE
;
6286 if (!ssh2_pkt_getbool(pktin
)) {
6288 * We have received an unequivocal Access
6289 * Denied. This can translate to a variety of
6292 * - if we'd just tried "none" authentication,
6293 * it's not worth printing anything at all
6295 * - if we'd just tried a public key _offer_,
6296 * the message should be "Server refused our
6297 * key" (or no message at all if the key
6298 * came from Pageant)
6300 * - if we'd just tried anything else, the
6301 * message really should be "Access denied".
6303 * Additionally, if we'd just tried password
6304 * authentication, we should break out of this
6305 * whole loop so as to go back to the username
6306 * prompt (iff we're configured to allow
6307 * username change attempts).
6309 if (s
->type
== AUTH_TYPE_NONE
) {
6311 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6312 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6313 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6314 c_write_str(ssh
, "Server refused our key\r\n");
6315 logevent("Server refused public key");
6316 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6317 /* server declined keyboard-interactive; ignore */
6319 c_write_str(ssh
, "Access denied\r\n");
6320 logevent("Access denied");
6321 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6322 ssh
->cfg
.change_username
) {
6323 /* XXX perhaps we should allow
6324 * keyboard-interactive to do this too? */
6325 s
->we_are_in
= FALSE
;
6330 c_write_str(ssh
, "Further authentication required\r\n");
6331 logevent("Further authentication required");
6335 in_commasep_string("publickey", methods
, methlen
);
6337 in_commasep_string("password", methods
, methlen
);
6338 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6339 in_commasep_string("keyboard-interactive", methods
, methlen
);
6343 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6347 * Most password/passphrase prompts will be
6348 * non-echoing, so we set this to 0 by default.
6349 * Exception is that some keyboard-interactive prompts
6350 * can be echoing, in which case we'll set this to 1.
6354 if (!s
->method
&& s
->can_pubkey
&&
6355 agent_exists() && !s
->tried_agent
) {
6357 * Attempt public-key authentication using Pageant.
6362 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6363 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6365 s
->tried_agent
= TRUE
;
6367 logevent("Pageant is running. Requesting keys.");
6369 /* Request the keys held by the agent. */
6370 PUT_32BIT(s
->request
, 1);
6371 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6372 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6373 ssh_agent_callback
, ssh
)) {
6377 bombout(("Unexpected data from server while"
6378 " waiting for agent response"));
6381 } while (pktin
|| inlen
> 0);
6382 r
= ssh
->agent_response
;
6383 s
->responselen
= ssh
->agent_response_len
;
6385 s
->response
= (unsigned char *) r
;
6386 if (s
->response
&& s
->responselen
>= 5 &&
6387 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6388 s
->p
= s
->response
+ 5;
6389 s
->nkeys
= GET_32BIT(s
->p
);
6393 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6396 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6401 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6404 s
->pklen
= GET_32BIT(s
->p
);
6406 if (s
->publickey_blob
&&
6407 s
->pklen
== s
->publickey_bloblen
&&
6408 !memcmp(s
->p
, s
->publickey_blob
,
6409 s
->publickey_bloblen
)) {
6410 logevent("This key matches configured key file");
6411 s
->tried_pubkey_config
= 1;
6413 s
->pkblob
= (char *)s
->p
;
6415 s
->alglen
= GET_32BIT(s
->pkblob
);
6416 s
->alg
= s
->pkblob
+ 4;
6417 s
->commentlen
= GET_32BIT(s
->p
);
6419 s
->commentp
= (char *)s
->p
;
6420 s
->p
+= s
->commentlen
;
6421 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6422 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6423 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6424 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6425 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6426 ssh2_pkt_addstring_start(s
->pktout
);
6427 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6428 ssh2_pkt_addstring_start(s
->pktout
);
6429 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6430 ssh2_pkt_send(ssh
, s
->pktout
);
6432 crWaitUntilV(pktin
);
6433 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6434 logevent("Key refused");
6438 if (flags
& FLAG_VERBOSE
) {
6439 c_write_str(ssh
, "Authenticating with "
6441 c_write(ssh
, s
->commentp
, s
->commentlen
);
6442 c_write_str(ssh
, "\" from agent\r\n");
6446 * Server is willing to accept the key.
6447 * Construct a SIGN_REQUEST.
6449 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6450 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6451 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6452 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6453 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6454 ssh2_pkt_addstring_start(s
->pktout
);
6455 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6456 ssh2_pkt_addstring_start(s
->pktout
);
6457 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6459 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6460 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6462 s
->len
= 1; /* message type */
6463 s
->len
+= 4 + s
->pklen
; /* key blob */
6464 s
->len
+= 4 + s
->siglen
; /* data to sign */
6465 s
->len
+= 4; /* flags */
6466 s
->agentreq
= snewn(4 + s
->len
, char);
6467 PUT_32BIT(s
->agentreq
, s
->len
);
6468 s
->q
= s
->agentreq
+ 4;
6469 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6470 PUT_32BIT(s
->q
, s
->pklen
);
6472 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6474 PUT_32BIT(s
->q
, s
->siglen
);
6476 /* Now the data to be signed... */
6477 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6478 PUT_32BIT(s
->q
, 20);
6481 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6483 memcpy(s
->q
, s
->pktout
->data
+ 5,
6484 s
->pktout
->length
- 5);
6485 s
->q
+= s
->pktout
->length
- 5;
6486 /* And finally the (zero) flags word. */
6488 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6490 ssh_agent_callback
, ssh
)) {
6494 bombout(("Unexpected data from server"
6495 " while waiting for agent"
6499 } while (pktin
|| inlen
> 0);
6500 vret
= ssh
->agent_response
;
6501 s
->retlen
= ssh
->agent_response_len
;
6506 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6507 logevent("Sending Pageant's response");
6508 ssh2_add_sigblob(ssh
, s
->pktout
,
6509 s
->pkblob
, s
->pklen
,
6511 GET_32BIT(s
->ret
+ 5));
6512 ssh2_pkt_send(ssh
, s
->pktout
);
6517 ("Pageant failed to answer challenge");
6528 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6529 && !s
->tried_pubkey_config
) {
6530 unsigned char *pub_blob
;
6531 char *algorithm
, *comment
;
6534 s
->tried_pubkey_config
= TRUE
;
6536 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6537 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6540 * Try the public key supplied in the configuration.
6542 * First, offer the public blob to see if the server is
6543 * willing to accept it.
6546 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6551 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6552 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6553 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6554 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6555 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6556 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6557 ssh2_pkt_addstring_start(s
->pktout
);
6558 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6560 ssh2_pkt_send(ssh
, s
->pktout
);
6561 logevent("Offered public key");
6563 crWaitUntilV(pktin
);
6564 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6566 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6567 continue; /* key refused; give up on it */
6570 logevent("Offer of public key accepted");
6572 * Actually attempt a serious authentication using
6575 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6576 sprintf(s
->pwprompt
,
6577 "Passphrase for key \"%.100s\": ",
6583 if (flags
& FLAG_VERBOSE
) {
6584 c_write_str(ssh
, "Authenticating with public key \"");
6585 c_write_str(ssh
, comment
);
6586 c_write_str(ssh
, "\"\r\n");
6588 s
->method
= AUTH_PUBLICKEY_FILE
;
6592 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6593 !s
->kbd_inter_running
) {
6594 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6595 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6597 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6598 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6600 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6601 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6602 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6603 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6604 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6605 ssh2_pkt_addstring(s
->pktout
, "");
6606 ssh2_pkt_send(ssh
, s
->pktout
);
6608 crWaitUntilV(pktin
);
6609 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6610 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6612 logevent("Keyboard-interactive authentication refused");
6613 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6614 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6618 s
->kbd_inter_running
= TRUE
;
6622 if (s
->kbd_inter_running
) {
6623 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6624 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6626 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6627 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6629 if (s
->curr_prompt
== 0) {
6631 * We've got a fresh USERAUTH_INFO_REQUEST.
6632 * Display header data, and start going through
6635 char *name
, *inst
, *lang
;
6636 int name_len
, inst_len
, lang_len
;
6638 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6639 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6640 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6642 c_write_untrusted(ssh
, name
, name_len
);
6643 c_write_str(ssh
, "\r\n");
6646 c_write_untrusted(ssh
, inst
, inst_len
);
6647 c_write_str(ssh
, "\r\n");
6649 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6653 * If there are prompts remaining in the packet,
6654 * display one and get a response.
6656 if (s
->curr_prompt
< s
->num_prompts
) {
6660 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6661 if (prompt_len
> 0) {
6662 static const char trunc
[] = "<prompt truncated>: ";
6663 static const int prlen
= sizeof(s
->pwprompt
) -
6665 if (prompt_len
> prlen
) {
6666 memcpy(s
->pwprompt
, prompt
, prlen
);
6667 strcpy(s
->pwprompt
+ prlen
, trunc
);
6669 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6670 s
->pwprompt
[prompt_len
] = '\0';
6674 "<server failed to send prompt>: ");
6676 s
->echo
= ssh2_pkt_getbool(pktin
);
6682 if (!s
->method
&& s
->can_passwd
) {
6683 s
->method
= AUTH_PASSWORD
;
6684 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6685 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6686 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6693 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6694 sizeof(s
->password
), TRUE
)) {
6696 * get_line failed to get a password (for
6697 * example because one was supplied on the
6698 * command line which has already failed to
6701 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6702 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6703 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6705 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6706 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6707 logevent("Unable to authenticate");
6708 connection_fatal(ssh
->frontend
,
6709 "Unable to authenticate");
6710 ssh
->close_expected
= TRUE
;
6711 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6715 int ret
; /* need not be saved across crReturn */
6716 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6719 setup_userpass_input(ssh
, s
->password
,
6720 sizeof(s
->password
), s
->echo
);
6722 crWaitUntilV(!pktin
);
6723 ret
= process_userpass_input(ssh
, in
, inlen
);
6727 c_write_str(ssh
, "\r\n");
6731 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6733 * We have our passphrase. Now try the actual authentication.
6735 struct ssh2_userkey
*key
;
6736 const char *error
= NULL
;
6738 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6740 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6741 if (key
== SSH2_WRONG_PASSPHRASE
) {
6742 c_write_str(ssh
, "Wrong passphrase\r\n");
6743 s
->tried_pubkey_config
= FALSE
;
6745 c_write_str(ssh
, "Unable to load private key (");
6746 c_write_str(ssh
, error
);
6747 c_write_str(ssh
, ")\r\n");
6748 s
->tried_pubkey_config
= TRUE
;
6750 /* Send a spurious AUTH_NONE to return to the top. */
6751 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6752 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6753 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6754 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6755 ssh2_pkt_send(ssh
, s
->pktout
);
6756 s
->type
= AUTH_TYPE_NONE
;
6758 unsigned char *pkblob
, *sigblob
, *sigdata
;
6759 int pkblob_len
, sigblob_len
, sigdata_len
;
6763 * We have loaded the private key and the server
6764 * has announced that it's willing to accept it.
6765 * Hallelujah. Generate a signature and send it.
6767 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6768 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6769 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6770 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6771 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6772 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6773 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6774 ssh2_pkt_addstring_start(s
->pktout
);
6775 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6778 * The data to be signed is:
6782 * followed by everything so far placed in the
6785 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6786 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6788 sigdata
= snewn(sigdata_len
, unsigned char);
6790 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6791 PUT_32BIT(sigdata
+p
, 20);
6794 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6795 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6796 s
->pktout
->length
- 5);
6797 p
+= s
->pktout
->length
- 5;
6798 assert(p
== sigdata_len
);
6799 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6800 sigdata_len
, &sigblob_len
);
6801 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6802 sigblob
, sigblob_len
);
6807 ssh2_pkt_send(ssh
, s
->pktout
);
6808 s
->type
= AUTH_TYPE_PUBLICKEY
;
6809 key
->alg
->freekey(key
->data
);
6811 } else if (s
->method
== AUTH_PASSWORD
) {
6813 * We pad out the password packet to 256 bytes to make
6814 * it harder for an attacker to find the length of the
6817 * Anyone using a password longer than 256 bytes
6818 * probably doesn't have much to worry about from
6819 * people who find out how long their password is!
6821 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6822 s
->pktout
->forcepad
= 256;
6823 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6824 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6825 ssh2_pkt_addstring(s
->pktout
, "password");
6826 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6827 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6828 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6829 memset(s
->password
, 0, sizeof(s
->password
));
6830 end_log_omission(ssh
, s
->pktout
);
6831 ssh2_pkt_send(ssh
, s
->pktout
);
6832 logevent("Sent password");
6833 s
->type
= AUTH_TYPE_PASSWORD
;
6834 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6835 if (s
->curr_prompt
== 0) {
6836 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6837 s
->pktout
->forcepad
= 256;
6838 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6840 if (s
->need_pw
) { /* only add pw if we just got one! */
6841 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6842 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6843 memset(s
->password
, 0, sizeof(s
->password
));
6844 end_log_omission(ssh
, s
->pktout
);
6847 if (s
->curr_prompt
>= s
->num_prompts
) {
6848 ssh2_pkt_send(ssh
, s
->pktout
);
6851 * If there are prompts remaining, we set
6852 * `gotit' so that we won't attempt to get
6853 * another packet. Then we go back round the
6854 * loop and will end up retrieving another
6855 * prompt out of the existing packet. Funky or
6860 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6862 c_write_str(ssh
, "No supported authentication methods"
6863 " left to try!\r\n");
6864 logevent("No supported authentications offered."
6866 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6867 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6868 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6869 " methods available");
6870 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6871 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6872 ssh
->close_expected
= TRUE
;
6873 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6877 } while (!s
->we_are_in
);
6880 * Now we're authenticated for the connection protocol. The
6881 * connection protocol will automatically have started at this
6882 * point; there's no need to send SERVICE_REQUEST.
6885 ssh
->channels
= newtree234(ssh_channelcmp
);
6888 * Set up handlers for some connection protocol messages, so we
6889 * don't have to handle them repeatedly in this coroutine.
6891 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6892 ssh2_msg_channel_window_adjust
;
6893 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6894 ssh2_msg_global_request
;
6897 * Create the main session channel.
6899 if (!ssh
->cfg
.ssh_no_shell
) {
6900 ssh
->mainchan
= snew(struct ssh_channel
);
6901 ssh
->mainchan
->ssh
= ssh
;
6902 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6903 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6904 ssh2_pkt_addstring(s
->pktout
, "session");
6905 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6906 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6907 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6908 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6909 ssh2_pkt_send(ssh
, s
->pktout
);
6910 crWaitUntilV(pktin
);
6911 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6912 bombout(("Server refused to open a session"));
6914 /* FIXME: error data comes back in FAILURE packet */
6916 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6917 bombout(("Server's channel confirmation cited wrong channel"));
6920 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6921 ssh
->mainchan
->halfopen
= FALSE
;
6922 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6923 ssh
->mainchan
->closes
= 0;
6924 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6925 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6926 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6927 add234(ssh
->channels
, ssh
->mainchan
);
6928 update_specials_menu(ssh
->frontend
);
6929 logevent("Opened channel for session");
6931 ssh
->mainchan
= NULL
;
6934 * Now we have a channel, make dispatch table entries for
6935 * general channel-based messages.
6937 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6938 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6939 ssh2_msg_channel_data
;
6940 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6941 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6942 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6943 ssh2_msg_channel_open_confirmation
;
6944 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6945 ssh2_msg_channel_open_failure
;
6946 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6947 ssh2_msg_channel_request
;
6948 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6949 ssh2_msg_channel_open
;
6952 * Potentially enable X11 forwarding.
6954 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6955 char proto
[20], data
[64];
6956 logevent("Requesting X11 forwarding");
6957 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6958 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6959 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6960 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6961 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6962 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6963 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6964 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6965 ssh2_pkt_addstring(s
->pktout
, proto
);
6966 ssh2_pkt_addstring(s
->pktout
, data
);
6967 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6968 ssh2_pkt_send(ssh
, s
->pktout
);
6970 crWaitUntilV(pktin
);
6972 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6973 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6974 bombout(("Unexpected response to X11 forwarding request:"
6975 " packet type %d", pktin
->type
));
6978 logevent("X11 forwarding refused");
6980 logevent("X11 forwarding enabled");
6981 ssh
->X11_fwd_enabled
= TRUE
;
6986 * Enable port forwardings.
6988 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6991 * Potentially enable agent forwarding.
6993 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6994 logevent("Requesting OpenSSH-style agent forwarding");
6995 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6996 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6997 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6998 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6999 ssh2_pkt_send(ssh
, s
->pktout
);
7001 crWaitUntilV(pktin
);
7003 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7004 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7005 bombout(("Unexpected response to agent forwarding request:"
7006 " packet type %d", pktin
->type
));
7009 logevent("Agent forwarding refused");
7011 logevent("Agent forwarding enabled");
7012 ssh
->agentfwd_enabled
= TRUE
;
7017 * Now allocate a pty for the session.
7019 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
7020 /* Unpick the terminal-speed string. */
7021 /* XXX perhaps we should allow no speeds to be sent. */
7022 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
7023 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
7024 /* Build the pty request. */
7025 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7026 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7027 ssh2_pkt_addstring(s
->pktout
, "pty-req");
7028 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7029 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
7030 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
7031 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
7032 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
7033 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
7034 ssh2_pkt_addstring_start(s
->pktout
);
7035 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
7036 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7037 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
7038 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7039 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7040 ssh2_pkt_send(ssh
, s
->pktout
);
7041 ssh
->state
= SSH_STATE_INTERMED
;
7043 crWaitUntilV(pktin
);
7045 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7046 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7047 bombout(("Unexpected response to pty request:"
7048 " packet type %d", pktin
->type
));
7051 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7052 ssh
->editing
= ssh
->echoing
= 1;
7054 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7055 ssh
->ospeed
, ssh
->ispeed
);
7058 ssh
->editing
= ssh
->echoing
= 1;
7062 * Send environment variables.
7064 * Simplest thing here is to send all the requests at once, and
7065 * then wait for a whole bunch of successes or failures.
7067 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7068 char *e
= ssh
->cfg
.environmt
;
7069 char *var
, *varend
, *val
;
7075 while (*e
&& *e
!= '\t') e
++;
7077 if (*e
== '\t') e
++;
7082 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7083 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7084 ssh2_pkt_addstring(s
->pktout
, "env");
7085 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7086 ssh2_pkt_addstring_start(s
->pktout
);
7087 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7088 ssh2_pkt_addstring(s
->pktout
, val
);
7089 ssh2_pkt_send(ssh
, s
->pktout
);
7094 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7097 s
->env_left
= s
->num_env
;
7099 while (s
->env_left
> 0) {
7100 crWaitUntilV(pktin
);
7102 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7103 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7104 bombout(("Unexpected response to environment request:"
7105 " packet type %d", pktin
->type
));
7115 if (s
->env_ok
== s
->num_env
) {
7116 logevent("All environment variables successfully set");
7117 } else if (s
->env_ok
== 0) {
7118 logevent("All environment variables refused");
7119 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7121 logeventf(ssh
, "%d environment variables refused",
7122 s
->num_env
- s
->env_ok
);
7123 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7128 * Start a shell or a remote command. We may have to attempt
7129 * this twice if the config data has provided a second choice
7132 if (ssh
->mainchan
) while (1) {
7136 if (ssh
->fallback_cmd
) {
7137 subsys
= ssh
->cfg
.ssh_subsys2
;
7138 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7140 subsys
= ssh
->cfg
.ssh_subsys
;
7141 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7144 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7145 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7147 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7148 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7149 ssh2_pkt_addstring(s
->pktout
, cmd
);
7151 ssh2_pkt_addstring(s
->pktout
, "exec");
7152 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7153 ssh2_pkt_addstring(s
->pktout
, cmd
);
7155 ssh2_pkt_addstring(s
->pktout
, "shell");
7156 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7158 ssh2_pkt_send(ssh
, s
->pktout
);
7160 crWaitUntilV(pktin
);
7162 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7163 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7164 bombout(("Unexpected response to shell/command request:"
7165 " packet type %d", pktin
->type
));
7169 * We failed to start the command. If this is the
7170 * fallback command, we really are finished; if it's
7171 * not, and if the fallback command exists, try falling
7172 * back to it before complaining.
7174 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7175 logevent("Primary command failed; attempting fallback");
7176 ssh
->fallback_cmd
= TRUE
;
7179 bombout(("Server refused to start a shell/command"));
7182 logevent("Started a shell/command");
7187 ssh
->state
= SSH_STATE_SESSION
;
7188 if (ssh
->size_needed
)
7189 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7190 if (ssh
->eof_needed
)
7191 ssh_special(ssh
, TS_EOF
);
7197 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7202 s
->try_send
= FALSE
;
7206 * _All_ the connection-layer packets we expect to
7207 * receive are now handled by the dispatch table.
7208 * Anything that reaches here must be bogus.
7211 bombout(("Strange packet received: type %d", pktin
->type
));
7213 } else if (ssh
->mainchan
) {
7215 * We have spare data. Add it to the channel buffer.
7217 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7222 struct ssh_channel
*c
;
7224 * Try to send data on all channels if we can.
7226 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7229 continue; /* don't send on closing channels */
7230 bufsize
= ssh2_try_send(c
);
7233 case CHAN_MAINSESSION
:
7234 /* stdin need not receive an unthrottle
7235 * notification since it will be polled */
7238 x11_unthrottle(c
->u
.x11
.s
);
7241 /* agent sockets are request/response and need no
7242 * buffer management */
7245 pfd_unthrottle(c
->u
.pfd
.s
);
7257 * Handlers for SSH2 messages that might arrive at any moment.
7259 static void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7261 /* log reason code in disconnect message */
7263 int nowlen
, reason
, msglen
;
7265 reason
= ssh_pkt_getuint32(pktin
);
7266 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7268 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7269 buf
= dupprintf("Received disconnect message (%s)",
7270 ssh2_disconnect_reasons
[reason
]);
7272 buf
= dupprintf("Received disconnect message (unknown"
7273 " type %d)", reason
);
7277 buf
= dupprintf("Disconnection message text: %n%.*s",
7278 &nowlen
, msglen
, msg
);
7280 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7282 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7283 ssh2_disconnect_reasons
[reason
] : "unknown",
7288 static void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7290 /* log the debug message */
7295 /* XXX maybe we should actually take notice of this */
7296 always_display
= ssh2_pkt_getbool(pktin
);
7297 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7299 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7304 static void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7306 struct Packet
*pktout
;
7307 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7308 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7310 * UNIMPLEMENTED messages MUST appear in the same order as the
7311 * messages they respond to. Hence, never queue them.
7313 ssh2_pkt_send_noqueue(ssh
, pktout
);
7317 * Handle the top-level SSH2 protocol.
7319 static void ssh2_protocol_setup(Ssh ssh
)
7324 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7326 for (i
= 0; i
< 256; i
++)
7327 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7330 * Any message we actually understand, we set to NULL so that
7331 * the coroutines will get it.
7333 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7334 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7335 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7336 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7337 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7338 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7339 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7340 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7341 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7342 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7343 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7344 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7345 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7346 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7347 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7348 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7349 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7350 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7351 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7352 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7353 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7354 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7355 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7356 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7357 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7358 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7359 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7360 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7361 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7362 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7363 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7364 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7365 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7368 * These special message types we install handlers for.
7370 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7371 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7372 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7375 static void ssh2_timer(void *ctx
, long now
)
7379 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7380 now
- ssh
->next_rekey
>= 0) {
7381 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7385 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
7386 struct Packet
*pktin
)
7388 unsigned char *in
= (unsigned char *)vin
;
7389 if (ssh
->state
== SSH_STATE_CLOSED
)
7393 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7394 if (!ssh
->kex_in_progress
&&
7395 ssh
->max_data_size
!= 0 &&
7396 ssh
->incoming_data_size
> ssh
->max_data_size
)
7397 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7400 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7401 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7405 if (!ssh
->protocol_initial_phase_done
||
7406 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7407 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7408 !ssh
->protocol_initial_phase_done
) {
7409 ssh
->protocol_initial_phase_done
= TRUE
;
7411 * Allow authconn to initialise itself.
7413 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7416 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7421 * Called to set up the connection.
7423 * Returns an error message, or NULL on success.
7425 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7427 char *host
, int port
, char **realhost
, int nodelay
,
7433 ssh
= snew(struct ssh_tag
);
7434 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7435 ssh
->version
= 0; /* when not ready yet */
7438 ssh
->v1_cipher_ctx
= NULL
;
7439 ssh
->crcda_ctx
= NULL
;
7440 ssh
->cscipher
= NULL
;
7441 ssh
->cs_cipher_ctx
= NULL
;
7442 ssh
->sccipher
= NULL
;
7443 ssh
->sc_cipher_ctx
= NULL
;
7445 ssh
->cs_mac_ctx
= NULL
;
7447 ssh
->sc_mac_ctx
= NULL
;
7449 ssh
->cs_comp_ctx
= NULL
;
7451 ssh
->sc_comp_ctx
= NULL
;
7453 ssh
->kex_ctx
= NULL
;
7454 ssh
->hostkey
= NULL
;
7456 ssh
->close_expected
= FALSE
;
7457 ssh
->state
= SSH_STATE_PREPACKET
;
7458 ssh
->size_needed
= FALSE
;
7459 ssh
->eof_needed
= FALSE
;
7462 ssh
->deferred_send_data
= NULL
;
7463 ssh
->deferred_len
= 0;
7464 ssh
->deferred_size
= 0;
7465 ssh
->fallback_cmd
= 0;
7467 ssh
->x11auth
= NULL
;
7468 ssh
->v1_compressing
= FALSE
;
7469 ssh
->v2_outgoing_sequence
= 0;
7470 ssh
->ssh1_rdpkt_crstate
= 0;
7471 ssh
->ssh2_rdpkt_crstate
= 0;
7472 ssh
->do_ssh_init_crstate
= 0;
7473 ssh
->ssh_gotdata_crstate
= 0;
7474 ssh
->do_ssh1_connection_crstate
= 0;
7475 ssh
->do_ssh1_login_crstate
= 0;
7476 ssh
->do_ssh2_transport_crstate
= 0;
7477 ssh
->do_ssh2_authconn_crstate
= 0;
7478 ssh
->do_ssh_init_state
= NULL
;
7479 ssh
->do_ssh1_login_state
= NULL
;
7480 ssh
->do_ssh2_transport_state
= NULL
;
7481 ssh
->do_ssh2_authconn_state
= NULL
;
7482 ssh
->mainchan
= NULL
;
7483 ssh
->throttled_all
= 0;
7484 ssh
->v1_stdout_throttling
= 0;
7486 ssh
->queuelen
= ssh
->queuesize
= 0;
7487 ssh
->queueing
= FALSE
;
7488 ssh
->qhead
= ssh
->qtail
= NULL
;
7489 ssh
->deferred_rekey_reason
= NULL
;
7491 *backend_handle
= ssh
;
7494 if (crypto_startup() == 0)
7495 return "Microsoft high encryption pack not installed!";
7498 ssh
->frontend
= frontend_handle
;
7499 ssh
->term_width
= ssh
->cfg
.width
;
7500 ssh
->term_height
= ssh
->cfg
.height
;
7502 ssh
->channels
= NULL
;
7503 ssh
->rportfwds
= NULL
;
7504 ssh
->portfwds
= NULL
;
7509 ssh
->v1_throttle_count
= 0;
7510 ssh
->overall_bufsize
= 0;
7511 ssh
->fallback_cmd
= 0;
7513 ssh
->protocol
= NULL
;
7515 ssh
->protocol_initial_phase_done
= FALSE
;
7519 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7520 ssh
->deferred_data_size
= 0L;
7521 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7522 ssh
->kex_in_progress
= FALSE
;
7524 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7533 static void ssh_free(void *handle
)
7535 Ssh ssh
= (Ssh
) handle
;
7536 struct ssh_channel
*c
;
7537 struct ssh_rportfwd
*pf
;
7539 if (ssh
->v1_cipher_ctx
)
7540 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7541 if (ssh
->cs_cipher_ctx
)
7542 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7543 if (ssh
->sc_cipher_ctx
)
7544 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7545 if (ssh
->cs_mac_ctx
)
7546 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7547 if (ssh
->sc_mac_ctx
)
7548 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7549 if (ssh
->cs_comp_ctx
) {
7551 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7553 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7555 if (ssh
->sc_comp_ctx
) {
7557 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7559 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7562 dh_cleanup(ssh
->kex_ctx
);
7563 sfree(ssh
->savedhost
);
7565 while (ssh
->queuelen
-- > 0)
7566 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7569 while (ssh
->qhead
) {
7570 struct queued_handler
*qh
= ssh
->qhead
;
7571 ssh
->qhead
= qh
->next
;
7574 ssh
->qhead
= ssh
->qtail
= NULL
;
7576 if (ssh
->channels
) {
7577 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7580 if (c
->u
.x11
.s
!= NULL
)
7581 x11_close(c
->u
.x11
.s
);
7584 if (c
->u
.pfd
.s
!= NULL
)
7585 pfd_close(c
->u
.pfd
.s
);
7590 freetree234(ssh
->channels
);
7591 ssh
->channels
= NULL
;
7594 if (ssh
->rportfwds
) {
7595 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7597 freetree234(ssh
->rportfwds
);
7598 ssh
->rportfwds
= NULL
;
7600 sfree(ssh
->deferred_send_data
);
7602 x11_free_auth(ssh
->x11auth
);
7603 sfree(ssh
->do_ssh_init_state
);
7604 sfree(ssh
->do_ssh1_login_state
);
7605 sfree(ssh
->do_ssh2_transport_state
);
7606 sfree(ssh
->do_ssh2_authconn_state
);
7607 if (ssh
->crcda_ctx
) {
7608 crcda_free_context(ssh
->crcda_ctx
);
7609 ssh
->crcda_ctx
= NULL
;
7612 ssh_do_close(ssh
, TRUE
);
7613 expire_timer_context(ssh
);
7615 pinger_free(ssh
->pinger
);
7622 * Reconfigure the SSH backend.
7624 static void ssh_reconfig(void *handle
, Config
*cfg
)
7626 Ssh ssh
= (Ssh
) handle
;
7627 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7628 unsigned long old_max_data_size
;
7630 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7631 ssh_setup_portfwd(ssh
, cfg
);
7633 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7634 cfg
->ssh_rekey_time
!= 0) {
7635 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7636 long now
= GETTICKCOUNT();
7638 if (new_next
- now
< 0) {
7639 rekeying
= "timeout shortened";
7641 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7645 old_max_data_size
= ssh
->max_data_size
;
7646 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7647 if (old_max_data_size
!= ssh
->max_data_size
&&
7648 ssh
->max_data_size
!= 0) {
7649 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7650 ssh
->incoming_data_size
> ssh
->max_data_size
)
7651 rekeying
= "data limit lowered";
7654 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7655 rekeying
= "compression setting changed";
7656 rekey_mandatory
= TRUE
;
7659 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7660 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7661 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7662 rekeying
= "cipher settings changed";
7663 rekey_mandatory
= TRUE
;
7666 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7669 if (!ssh
->kex_in_progress
) {
7670 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7671 } else if (rekey_mandatory
) {
7672 ssh
->deferred_rekey_reason
= rekeying
;
7678 * Called to send data down the Telnet connection.
7680 static int ssh_send(void *handle
, char *buf
, int len
)
7682 Ssh ssh
= (Ssh
) handle
;
7684 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7687 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7689 return ssh_sendbuffer(ssh
);
7693 * Called to query the current amount of buffered stdin data.
7695 static int ssh_sendbuffer(void *handle
)
7697 Ssh ssh
= (Ssh
) handle
;
7700 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7704 * If the SSH socket itself has backed up, add the total backup
7705 * size on that to any individual buffer on the stdin channel.
7708 if (ssh
->throttled_all
)
7709 override_value
= ssh
->overall_bufsize
;
7711 if (ssh
->version
== 1) {
7712 return override_value
;
7713 } else if (ssh
->version
== 2) {
7714 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7715 return override_value
;
7717 return (override_value
+
7718 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7725 * Called to set the size of the window from SSH's POV.
7727 static void ssh_size(void *handle
, int width
, int height
)
7729 Ssh ssh
= (Ssh
) handle
;
7730 struct Packet
*pktout
;
7732 ssh
->term_width
= width
;
7733 ssh
->term_height
= height
;
7735 switch (ssh
->state
) {
7736 case SSH_STATE_BEFORE_SIZE
:
7737 case SSH_STATE_PREPACKET
:
7738 case SSH_STATE_CLOSED
:
7739 break; /* do nothing */
7740 case SSH_STATE_INTERMED
:
7741 ssh
->size_needed
= TRUE
; /* buffer for later */
7743 case SSH_STATE_SESSION
:
7744 if (!ssh
->cfg
.nopty
) {
7745 if (ssh
->version
== 1) {
7746 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7747 PKT_INT
, ssh
->term_height
,
7748 PKT_INT
, ssh
->term_width
,
7749 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7750 } else if (ssh
->mainchan
) {
7751 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7752 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7753 ssh2_pkt_addstring(pktout
, "window-change");
7754 ssh2_pkt_addbool(pktout
, 0);
7755 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7756 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7757 ssh2_pkt_adduint32(pktout
, 0);
7758 ssh2_pkt_adduint32(pktout
, 0);
7759 ssh2_pkt_send(ssh
, pktout
);
7767 * Return a list of the special codes that make sense in this
7770 static const struct telnet_special
*ssh_get_specials(void *handle
)
7772 static const struct telnet_special ssh1_ignore_special
[] = {
7773 {"IGNORE message", TS_NOP
}
7775 static const struct telnet_special ssh2_transport_specials
[] = {
7776 {"IGNORE message", TS_NOP
},
7777 {"Repeat key exchange", TS_REKEY
},
7779 static const struct telnet_special ssh2_session_specials
[] = {
7782 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7783 * They include all the ISO C signals, but are a subset of the POSIX
7784 * required signals. */
7785 {"SIGINT (Interrupt)", TS_SIGINT
},
7786 {"SIGTERM (Terminate)", TS_SIGTERM
},
7787 {"SIGKILL (Kill)", TS_SIGKILL
},
7788 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7789 {"SIGHUP (Hangup)", TS_SIGHUP
},
7790 {"More signals", TS_SUBMENU
},
7791 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7792 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7793 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7794 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7797 static const struct telnet_special specials_end
[] = {
7800 /* XXX review this length for any changes: */
7801 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7802 lenof(ssh2_session_specials
) +
7803 lenof(specials_end
)];
7804 Ssh ssh
= (Ssh
) handle
;
7806 #define ADD_SPECIALS(name) \
7808 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7809 memcpy(&ssh_specials[i], name, sizeof name); \
7813 if (ssh
->version
== 1) {
7814 /* Don't bother offering IGNORE if we've decided the remote
7815 * won't cope with it, since we wouldn't bother sending it if
7817 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7818 ADD_SPECIALS(ssh1_ignore_special
);
7819 } else if (ssh
->version
== 2) {
7820 ADD_SPECIALS(ssh2_transport_specials
);
7822 ADD_SPECIALS(ssh2_session_specials
);
7823 } /* else we're not ready yet */
7826 ADD_SPECIALS(specials_end
);
7827 return ssh_specials
;
7835 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7836 * can send an EOF and collect resulting output (e.g. `plink
7839 static void ssh_special(void *handle
, Telnet_Special code
)
7841 Ssh ssh
= (Ssh
) handle
;
7842 struct Packet
*pktout
;
7844 if (code
== TS_EOF
) {
7845 if (ssh
->state
!= SSH_STATE_SESSION
) {
7847 * Buffer the EOF in case we are pre-SESSION, so we can
7848 * send it as soon as we reach SESSION.
7851 ssh
->eof_needed
= TRUE
;
7854 if (ssh
->version
== 1) {
7855 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7856 } else if (ssh
->mainchan
) {
7857 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7858 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7859 ssh2_pkt_send(ssh
, pktout
);
7861 logevent("Sent EOF message");
7862 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7863 if (ssh
->state
== SSH_STATE_CLOSED
7864 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7865 if (ssh
->version
== 1) {
7866 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7867 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7869 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7870 ssh2_pkt_addstring_start(pktout
);
7871 ssh2_pkt_send_noqueue(ssh
, pktout
);
7873 } else if (code
== TS_REKEY
) {
7874 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7875 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
7877 } else if (code
== TS_BRK
) {
7878 if (ssh
->state
== SSH_STATE_CLOSED
7879 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7880 if (ssh
->version
== 1) {
7881 logevent("Unable to send BREAK signal in SSH1");
7882 } else if (ssh
->mainchan
) {
7883 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7884 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7885 ssh2_pkt_addstring(pktout
, "break");
7886 ssh2_pkt_addbool(pktout
, 0);
7887 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7888 ssh2_pkt_send(ssh
, pktout
);
7891 /* Is is a POSIX signal? */
7892 char *signame
= NULL
;
7893 if (code
== TS_SIGABRT
) signame
= "ABRT";
7894 if (code
== TS_SIGALRM
) signame
= "ALRM";
7895 if (code
== TS_SIGFPE
) signame
= "FPE";
7896 if (code
== TS_SIGHUP
) signame
= "HUP";
7897 if (code
== TS_SIGILL
) signame
= "ILL";
7898 if (code
== TS_SIGINT
) signame
= "INT";
7899 if (code
== TS_SIGKILL
) signame
= "KILL";
7900 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7901 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7902 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7903 if (code
== TS_SIGTERM
) signame
= "TERM";
7904 if (code
== TS_SIGUSR1
) signame
= "USR1";
7905 if (code
== TS_SIGUSR2
) signame
= "USR2";
7906 /* The SSH-2 protocol does in principle support arbitrary named
7907 * signals, including signame@domain, but we don't support those. */
7909 /* It's a signal. */
7910 if (ssh
->version
== 2 && ssh
->mainchan
) {
7911 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7912 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7913 ssh2_pkt_addstring(pktout
, "signal");
7914 ssh2_pkt_addbool(pktout
, 0);
7915 ssh2_pkt_addstring(pktout
, signame
);
7916 ssh2_pkt_send(ssh
, pktout
);
7917 logeventf(ssh
, "Sent signal SIG%s", signame
);
7920 /* Never heard of it. Do nothing */
7925 void *new_sock_channel(void *handle
, Socket s
)
7927 Ssh ssh
= (Ssh
) handle
;
7928 struct ssh_channel
*c
;
7929 c
= snew(struct ssh_channel
);
7934 c
->localid
= alloc_channel_id(ssh
);
7936 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7938 bufchain_init(&c
->v
.v2
.outbuffer
);
7939 add234(ssh
->channels
, c
);
7945 * This is called when stdout/stderr (the entity to which
7946 * from_backend sends data) manages to clear some backlog.
7948 static void ssh_unthrottle(void *handle
, int bufsize
)
7950 Ssh ssh
= (Ssh
) handle
;
7951 if (ssh
->version
== 1) {
7952 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7953 ssh
->v1_stdout_throttling
= 0;
7954 ssh1_throttle(ssh
, -1);
7957 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7958 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7962 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7964 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7966 struct Packet
*pktout
;
7968 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7970 if (ssh
->version
== 1) {
7971 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7972 PKT_INT
, c
->localid
,
7975 /* PKT_STR, <org:orgport>, */
7978 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7979 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7980 ssh2_pkt_adduint32(pktout
, c
->localid
);
7981 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7982 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7983 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7984 ssh2_pkt_addstring(pktout
, hostname
);
7985 ssh2_pkt_adduint32(pktout
, port
);
7987 * We make up values for the originator data; partly it's
7988 * too much hassle to keep track, and partly I'm not
7989 * convinced the server should be told details like that
7990 * about my local network configuration.
7992 ssh2_pkt_addstring(pktout
, "client-side-connection");
7993 ssh2_pkt_adduint32(pktout
, 0);
7994 ssh2_pkt_send(ssh
, pktout
);
7998 static Socket
ssh_socket(void *handle
)
8000 Ssh ssh
= (Ssh
) handle
;
8004 static int ssh_sendok(void *handle
)
8006 Ssh ssh
= (Ssh
) handle
;
8007 return ssh
->send_ok
;
8010 static int ssh_ldisc(void *handle
, int option
)
8012 Ssh ssh
= (Ssh
) handle
;
8013 if (option
== LD_ECHO
)
8014 return ssh
->echoing
;
8015 if (option
== LD_EDIT
)
8016 return ssh
->editing
;
8020 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
8022 Ssh ssh
= (Ssh
) handle
;
8026 static void ssh_provide_logctx(void *handle
, void *logctx
)
8028 Ssh ssh
= (Ssh
) handle
;
8029 ssh
->logctx
= logctx
;
8032 static int ssh_return_exitcode(void *handle
)
8034 Ssh ssh
= (Ssh
) handle
;
8038 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8042 * cfg_info for SSH is the currently running version of the
8043 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8045 static int ssh_cfg_info(void *handle
)
8047 Ssh ssh
= (Ssh
) handle
;
8048 return ssh
->version
;
8052 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8053 * that fails. This variable is the means by which scp.c can reach
8054 * into the SSH code and find out which one it got.
8056 extern int ssh_fallback_cmd(void *handle
)
8058 Ssh ssh
= (Ssh
) handle
;
8059 return ssh
->fallback_cmd
;
8062 Backend ssh_backend
= {
8072 ssh_return_exitcode
,