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
;
440 * In SSH1, this value contains four bits:
442 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
443 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
444 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
445 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
447 * A channel is completely finished with when all four bits are set.
451 struct ssh1_data_channel
{
454 struct ssh2_data_channel
{
456 unsigned remwindow
, remmaxpkt
;
461 struct ssh_agent_channel
{
462 unsigned char *message
;
463 unsigned char msglen
[4];
464 unsigned lensofar
, totallen
;
466 struct ssh_x11_channel
{
469 struct ssh_pfd_channel
{
476 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
477 * 2 use this structure in different ways, reflecting SSH 2's
478 * altogether saner approach to port forwarding.
480 * In SSH 1, you arrange a remote forwarding by sending the server
481 * the remote port number, and the local destination host:port.
482 * When a connection comes in, the server sends you back that
483 * host:port pair, and you connect to it. This is a ready-made
484 * security hole if you're not on the ball: a malicious server
485 * could send you back _any_ host:port pair, so if you trustingly
486 * connect to the address it gives you then you've just opened the
487 * entire inside of your corporate network just by connecting
488 * through it to a dodgy SSH server. Hence, we must store a list of
489 * host:port pairs we _are_ trying to forward to, and reject a
490 * connection request from the server if it's not in the list.
492 * In SSH 2, each side of the connection minds its own business and
493 * doesn't send unnecessary information to the other. You arrange a
494 * remote forwarding by sending the server just the remote port
495 * number. When a connection comes in, the server tells you which
496 * of its ports was connected to; and _you_ have to remember what
497 * local host:port pair went with that port number.
499 * Hence, in SSH 1 this structure is indexed by destination
500 * host:port pair, whereas in SSH 2 it is indexed by source port.
502 struct ssh_portfwd
; /* forward declaration */
504 struct ssh_rportfwd
{
505 unsigned sport
, dport
;
508 struct ssh_portfwd
*pfrec
;
510 #define free_rportfwd(pf) ( \
511 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
514 * Separately to the rportfwd tree (which is for looking up port
515 * open requests from the server), a tree of _these_ structures is
516 * used to keep track of all the currently open port forwardings,
517 * so that we can reconfigure in mid-session if the user requests
521 enum { DESTROY
, KEEP
, CREATE
} status
;
523 unsigned sport
, dport
;
526 struct ssh_rportfwd
*remote
;
530 #define free_portfwd(pf) ( \
531 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
532 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
537 unsigned long sequence
;
542 long encrypted_len
; /* for SSH2 total-size counting */
545 * State associated with packet logging
549 struct logblank_t
*blanks
;
552 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
553 struct Packet
*pktin
);
554 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
555 struct Packet
*pktin
);
556 static void ssh1_protocol_setup(Ssh ssh
);
557 static void ssh2_protocol_setup(Ssh ssh
);
558 static void ssh_size(void *handle
, int width
, int height
);
559 static void ssh_special(void *handle
, Telnet_Special
);
560 static int ssh2_try_send(struct ssh_channel
*c
);
561 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
562 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
563 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
564 static int ssh_sendbuffer(void *handle
);
565 static int ssh_do_close(Ssh ssh
, int notify_exit
);
566 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
567 static int ssh2_pkt_getbool(struct Packet
*pkt
);
568 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
569 static void ssh2_timer(void *ctx
, long now
);
570 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
571 struct Packet
*pktin
);
573 struct rdpkt1_state_tag
{
574 long len
, pad
, biglen
, to_read
;
575 unsigned long realcrc
, gotcrc
;
579 struct Packet
*pktin
;
582 struct rdpkt2_state_tag
{
583 long len
, pad
, payload
, packetlen
, maclen
;
586 unsigned long incoming_sequence
;
587 struct Packet
*pktin
;
590 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
591 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
593 struct queued_handler
;
594 struct queued_handler
{
596 chandler_fn_t handler
;
598 struct queued_handler
*next
;
602 const struct plug_function_table
*fn
;
603 /* the above field _must_ be first in the structure */
605 SHA_State exhash
, exhashbase
;
612 unsigned char session_key
[32];
614 int v1_remote_protoflags
;
615 int v1_local_protoflags
;
616 int agentfwd_enabled
;
619 const struct ssh_cipher
*cipher
;
622 const struct ssh2_cipher
*cscipher
, *sccipher
;
623 void *cs_cipher_ctx
, *sc_cipher_ctx
;
624 const struct ssh_mac
*csmac
, *scmac
;
625 void *cs_mac_ctx
, *sc_mac_ctx
;
626 const struct ssh_compress
*cscomp
, *sccomp
;
627 void *cs_comp_ctx
, *sc_comp_ctx
;
628 const struct ssh_kex
*kex
;
629 const struct ssh_signkey
*hostkey
;
630 unsigned char v2_session_id
[20];
636 int echoing
, editing
;
640 int ospeed
, ispeed
; /* temporaries */
641 int term_width
, term_height
;
643 tree234
*channels
; /* indexed by local id */
644 struct ssh_channel
*mainchan
; /* primary session channel */
648 tree234
*rportfwds
, *portfwds
;
652 SSH_STATE_BEFORE_SIZE
,
658 int size_needed
, eof_needed
;
660 struct Packet
**queue
;
661 int queuelen
, queuesize
;
663 unsigned char *deferred_send_data
;
664 int deferred_len
, deferred_size
;
667 * Gross hack: pscp will try to start SFTP but fall back to
668 * scp1 if that fails. This variable is the means by which
669 * scp.c can reach into the SSH code and find out which one it
675 * Used for username and password input.
677 char *userpass_input_buffer
;
678 int userpass_input_buflen
;
679 int userpass_input_bufpos
;
680 int userpass_input_echo
;
687 int v1_throttle_count
;
690 int v1_stdout_throttling
;
691 int v2_outgoing_sequence
;
693 int ssh1_rdpkt_crstate
;
694 int ssh2_rdpkt_crstate
;
695 int do_ssh_init_crstate
;
696 int ssh_gotdata_crstate
;
697 int do_ssh1_login_crstate
;
698 int do_ssh1_connection_crstate
;
699 int do_ssh2_transport_crstate
;
700 int do_ssh2_authconn_crstate
;
702 void *do_ssh_init_state
;
703 void *do_ssh1_login_state
;
704 void *do_ssh2_transport_state
;
705 void *do_ssh2_authconn_state
;
707 struct rdpkt1_state_tag rdpkt1_state
;
708 struct rdpkt2_state_tag rdpkt2_state
;
710 /* ssh1 and ssh2 use this for different things, but both use it */
711 int protocol_initial_phase_done
;
713 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
715 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
718 * We maintain a full _copy_ of a Config structure here, not
719 * merely a pointer to it. That way, when we're passed a new
720 * one for reconfiguration, we can check the differences and
721 * potentially reconfigure port forwardings etc in mid-session.
726 * Used to transfer data back from async agent callbacks.
728 void *agent_response
;
729 int agent_response_len
;
732 * Dispatch table for packet types that we may have to deal
735 handler_fn_t packet_dispatch
[256];
738 * Queues of one-off handler functions for success/failure
739 * indications from a request.
741 struct queued_handler
*qhead
, *qtail
;
744 * This module deals with sending keepalives.
749 * Track incoming and outgoing data sizes and time, for
752 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
753 unsigned long max_data_size
;
755 long next_rekey
, last_rekey
;
756 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
759 #define logevent(s) logevent(ssh->frontend, s)
761 /* logevent, only printf-formatted. */
762 static void logeventf(Ssh ssh
, const char *fmt
, ...)
768 buf
= dupvprintf(fmt
, ap
);
774 #define bombout(msg) \
776 char *text = dupprintf msg; \
777 ssh_do_close(ssh, FALSE); \
779 connection_fatal(ssh->frontend, "%s", text); \
783 /* Functions to leave bits out of the SSH packet log file. */
785 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
787 if (ssh
->cfg
.logomitpass
)
788 pkt
->logmode
= blanktype
;
791 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
793 if (ssh
->cfg
.logomitdata
)
794 pkt
->logmode
= blanktype
;
797 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
799 pkt
->logmode
= PKTLOG_EMIT
;
802 static int ssh_channelcmp(void *av
, void *bv
)
804 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
805 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
806 if (a
->localid
< b
->localid
)
808 if (a
->localid
> b
->localid
)
812 static int ssh_channelfind(void *av
, void *bv
)
814 unsigned *a
= (unsigned *) av
;
815 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
823 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
825 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
826 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
828 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
829 return i
< 0 ?
-1 : +1;
830 if (a
->dport
> b
->dport
)
832 if (a
->dport
< b
->dport
)
837 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
839 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
840 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
842 if (a
->sport
> b
->sport
)
844 if (a
->sport
< b
->sport
)
850 * Special form of strcmp which can cope with NULL inputs. NULL is
851 * defined to sort before even the empty string.
853 static int nullstrcmp(const char *a
, const char *b
)
855 if (a
== NULL
&& b
== NULL
)
864 static int ssh_portcmp(void *av
, void *bv
)
866 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
867 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
869 if (a
->type
> b
->type
)
871 if (a
->type
< b
->type
)
873 if (a
->addressfamily
> b
->addressfamily
)
875 if (a
->addressfamily
< b
->addressfamily
)
877 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
878 return i
< 0 ?
-1 : +1;
879 if (a
->sport
> b
->sport
)
881 if (a
->sport
< b
->sport
)
883 if (a
->type
!= 'D') {
884 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
885 return i
< 0 ?
-1 : +1;
886 if (a
->dport
> b
->dport
)
888 if (a
->dport
< b
->dport
)
894 static int alloc_channel_id(Ssh ssh
)
896 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
897 unsigned low
, high
, mid
;
899 struct ssh_channel
*c
;
902 * First-fit allocation of channel numbers: always pick the
903 * lowest unused one. To do this, binary-search using the
904 * counted B-tree to find the largest channel ID which is in a
905 * contiguous sequence from the beginning. (Precisely
906 * everything in that sequence must have ID equal to its tree
907 * index plus CHANNEL_NUMBER_OFFSET.)
909 tsize
= count234(ssh
->channels
);
913 while (high
- low
> 1) {
914 mid
= (high
+ low
) / 2;
915 c
= index234(ssh
->channels
, mid
);
916 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
917 low
= mid
; /* this one is fine */
919 high
= mid
; /* this one is past it */
922 * Now low points to either -1, or the tree index of the
923 * largest ID in the initial sequence.
926 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
927 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
929 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
932 static void c_write(Ssh ssh
, const char *buf
, int len
)
934 if ((flags
& FLAG_STDERR
)) {
936 for (i
= 0; i
< len
; i
++)
938 fputc(buf
[i
], stderr
);
941 from_backend(ssh
->frontend
, 1, buf
, len
);
944 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
947 for (i
= 0; i
< len
; i
++) {
949 c_write(ssh
, "\r\n", 2);
950 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
951 c_write(ssh
, buf
+ i
, 1);
955 static void c_write_str(Ssh ssh
, const char *buf
)
957 c_write(ssh
, buf
, strlen(buf
));
960 static void ssh_free_packet(struct Packet
*pkt
)
965 static struct Packet
*ssh_new_packet(void)
967 struct Packet
*pkt
= snew(struct Packet
);
971 pkt
->logmode
= PKTLOG_EMIT
;
979 * Collect incoming data in the incoming packet buffer.
980 * Decipher and verify the packet when it is completely read.
981 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
982 * Update the *data and *datalen variables.
983 * Return a Packet structure when a packet is completed.
985 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
987 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
989 crBegin(ssh
->ssh1_rdpkt_crstate
);
991 st
->pktin
= ssh_new_packet();
994 st
->pktin
->length
= 0;
996 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
997 while ((*datalen
) == 0)
999 st
->len
= (st
->len
<< 8) + **data
;
1000 (*data
)++, (*datalen
)--;
1003 st
->pad
= 8 - (st
->len
% 8);
1004 st
->biglen
= st
->len
+ st
->pad
;
1005 st
->pktin
->length
= st
->len
- 5;
1007 if (st
->biglen
< 0) {
1008 bombout(("Extremely large packet length from server suggests"
1009 " data stream corruption"));
1010 ssh_free_packet(st
->pktin
);
1014 st
->pktin
->maxlen
= st
->biglen
;
1015 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1017 st
->to_read
= st
->biglen
;
1018 st
->p
= st
->pktin
->data
;
1019 while (st
->to_read
> 0) {
1020 st
->chunk
= st
->to_read
;
1021 while ((*datalen
) == 0)
1023 if (st
->chunk
> (*datalen
))
1024 st
->chunk
= (*datalen
);
1025 memcpy(st
->p
, *data
, st
->chunk
);
1027 *datalen
-= st
->chunk
;
1029 st
->to_read
-= st
->chunk
;
1032 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1033 st
->biglen
, NULL
)) {
1034 bombout(("Network attack (CRC compensation) detected!"));
1035 ssh_free_packet(st
->pktin
);
1040 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1042 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1043 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1044 if (st
->gotcrc
!= st
->realcrc
) {
1045 bombout(("Incorrect CRC received on packet"));
1046 ssh_free_packet(st
->pktin
);
1050 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1051 st
->pktin
->savedpos
= 0;
1053 if (ssh
->v1_compressing
) {
1054 unsigned char *decompblk
;
1056 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1057 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1058 &decompblk
, &decomplen
)) {
1059 bombout(("Zlib decompression encountered invalid data"));
1060 ssh_free_packet(st
->pktin
);
1064 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1065 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1066 st
->pktin
->data
= sresize(st
->pktin
->data
,
1067 st
->pktin
->maxlen
+ APIEXTRA
,
1069 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1072 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1074 st
->pktin
->length
= decomplen
- 1;
1077 st
->pktin
->type
= st
->pktin
->body
[-1];
1080 * Log incoming packet, possibly omitting sensitive fields.
1084 struct logblank_t blank
;
1085 if (ssh
->cfg
.logomitdata
) {
1086 int do_blank
= FALSE
, blank_prefix
= 0;
1087 /* "Session data" packets - omit the data field */
1088 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1089 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1090 do_blank
= TRUE
; blank_prefix
= 0;
1091 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1092 do_blank
= TRUE
; blank_prefix
= 4;
1095 blank
.offset
= blank_prefix
;
1096 blank
.len
= st
->pktin
->length
;
1097 blank
.type
= PKTLOG_OMIT
;
1101 log_packet(ssh
->logctx
,
1102 PKT_INCOMING
, st
->pktin
->type
,
1103 ssh1_pkt_type(st
->pktin
->type
),
1104 st
->pktin
->body
, st
->pktin
->length
,
1108 crFinish(st
->pktin
);
1111 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1113 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1115 crBegin(ssh
->ssh2_rdpkt_crstate
);
1117 st
->pktin
= ssh_new_packet();
1119 st
->pktin
->type
= 0;
1120 st
->pktin
->length
= 0;
1122 st
->cipherblk
= ssh
->sccipher
->blksize
;
1125 if (st
->cipherblk
< 8)
1128 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1131 * Acquire and decrypt the first block of the packet. This will
1132 * contain the length and padding details.
1134 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1135 while ((*datalen
) == 0)
1137 st
->pktin
->data
[st
->i
] = *(*data
)++;
1142 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1143 st
->pktin
->data
, st
->cipherblk
);
1146 * Now get the length and padding figures.
1148 st
->len
= GET_32BIT(st
->pktin
->data
);
1149 st
->pad
= st
->pktin
->data
[4];
1152 * _Completely_ silly lengths should be stomped on before they
1153 * do us any more damage.
1155 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1156 bombout(("Incoming packet was garbled on decryption"));
1157 ssh_free_packet(st
->pktin
);
1162 * This enables us to deduce the payload length.
1164 st
->payload
= st
->len
- st
->pad
- 1;
1166 st
->pktin
->length
= st
->payload
+ 5;
1169 * So now we can work out the total packet length.
1171 st
->packetlen
= st
->len
+ 4;
1172 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1175 * Allocate memory for the rest of the packet.
1177 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1178 st
->pktin
->data
= sresize(st
->pktin
->data
,
1179 st
->pktin
->maxlen
+ APIEXTRA
,
1183 * Read and decrypt the remainder of the packet.
1185 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1187 while ((*datalen
) == 0)
1189 st
->pktin
->data
[st
->i
] = *(*data
)++;
1192 /* Decrypt everything _except_ the MAC. */
1194 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1195 st
->pktin
->data
+ st
->cipherblk
,
1196 st
->packetlen
- st
->cipherblk
);
1198 st
->pktin
->encrypted_len
= st
->packetlen
;
1204 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1205 st
->incoming_sequence
)) {
1206 bombout(("Incorrect MAC received on packet"));
1207 ssh_free_packet(st
->pktin
);
1211 st
->pktin
->sequence
= st
->incoming_sequence
++;
1214 * Decompress packet payload.
1217 unsigned char *newpayload
;
1220 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1221 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1222 &newpayload
, &newlen
)) {
1223 if (st
->pktin
->maxlen
< newlen
+ 5) {
1224 st
->pktin
->maxlen
= newlen
+ 5;
1225 st
->pktin
->data
= sresize(st
->pktin
->data
,
1226 st
->pktin
->maxlen
+ APIEXTRA
,
1229 st
->pktin
->length
= 5 + newlen
;
1230 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1235 st
->pktin
->savedpos
= 6;
1236 st
->pktin
->body
= st
->pktin
->data
;
1237 st
->pktin
->type
= st
->pktin
->data
[5];
1240 * Log incoming packet, possibly omitting sensitive fields.
1244 struct logblank_t blank
;
1245 if (ssh
->cfg
.logomitdata
) {
1246 int do_blank
= FALSE
, blank_prefix
= 0;
1247 /* "Session data" packets - omit the data field */
1248 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1249 do_blank
= TRUE
; blank_prefix
= 4;
1250 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1251 do_blank
= TRUE
; blank_prefix
= 8;
1254 blank
.offset
= blank_prefix
;
1255 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1256 blank
.type
= PKTLOG_OMIT
;
1260 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1261 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1262 st
->pktin
->data
+6, st
->pktin
->length
-6,
1266 crFinish(st
->pktin
);
1269 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1273 len
+= 5; /* type and CRC */
1274 pad
= 8 - (len
% 8);
1277 pkt
->length
= len
- 5;
1278 if (pkt
->maxlen
< biglen
) {
1279 pkt
->maxlen
= biglen
;
1280 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1282 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1285 static struct Packet
*s_wrpkt_start(int type
, int len
)
1287 struct Packet
*pkt
= ssh_new_packet();
1288 ssh1_pktout_size(pkt
, len
);
1290 /* Initialise log omission state */
1296 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1302 * XXX various versions of SC (including 8.8.4) screw up the
1303 * register allocation in this function and use the same register
1304 * (D6) for len and as a temporary, with predictable results. The
1305 * following sledgehammer prevents this.
1311 pkt
->body
[-1] = pkt
->type
;
1314 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1315 ssh1_pkt_type(pkt
->type
),
1316 pkt
->body
, pkt
->length
,
1317 pkt
->nblanks
, pkt
->blanks
);
1318 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1321 if (ssh
->v1_compressing
) {
1322 unsigned char *compblk
;
1324 zlib_compress_block(ssh
->cs_comp_ctx
,
1325 pkt
->body
- 1, pkt
->length
+ 1,
1326 &compblk
, &complen
);
1327 ssh1_pktout_size(pkt
, complen
- 1);
1328 memcpy(pkt
->body
- 1, compblk
, complen
);
1332 len
= pkt
->length
+ 5; /* type and CRC */
1333 pad
= 8 - (len
% 8);
1336 for (i
= 0; i
< pad
; i
++)
1337 pkt
->data
[i
+ 4] = random_byte();
1338 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1339 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1340 PUT_32BIT(pkt
->data
, len
);
1343 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1348 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1351 len
= s_wrpkt_prepare(ssh
, pkt
);
1352 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1353 if (backlog
> SSH_MAX_BACKLOG
)
1354 ssh_throttle_all(ssh
, 1, backlog
);
1357 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1360 len
= s_wrpkt_prepare(ssh
, pkt
);
1361 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1362 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1363 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1367 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1368 ssh
->deferred_len
+= len
;
1372 * Construct a packet with the specified contents.
1374 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1375 va_list ap1
, va_list ap2
)
1377 unsigned char *p
, *argp
, argchar
;
1378 unsigned long argint
;
1379 int pktlen
, argtype
, arglen
;
1384 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1387 (void) va_arg(ap1
, int);
1391 (void) va_arg(ap1
, int);
1395 (void) va_arg(ap1
, unsigned char *);
1396 arglen
= va_arg(ap1
, int);
1400 argp
= va_arg(ap1
, unsigned char *);
1401 arglen
= strlen((char *)argp
);
1402 pktlen
+= 4 + arglen
;
1405 bn
= va_arg(ap1
, Bignum
);
1406 pktlen
+= ssh1_bignum_length(bn
);
1411 /* ignore this pass */
1418 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1421 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1422 int offset
= p
- pkt
->body
, len
= 0;
1424 /* Actual fields in the packet */
1426 argint
= va_arg(ap2
, int);
1427 PUT_32BIT(p
, argint
);
1431 argchar
= (unsigned char) va_arg(ap2
, int);
1436 argp
= va_arg(ap2
, unsigned char *);
1437 arglen
= va_arg(ap2
, int);
1438 memcpy(p
, argp
, arglen
);
1442 argp
= va_arg(ap2
, unsigned char *);
1443 arglen
= strlen((char *)argp
);
1444 PUT_32BIT(p
, arglen
);
1445 memcpy(p
+ 4, argp
, arglen
);
1449 bn
= va_arg(ap2
, Bignum
);
1450 len
= ssh1_write_bignum(p
, bn
);
1452 /* Tokens for modifications to packet logging */
1454 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1457 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1460 end_log_omission(ssh
, pkt
);
1464 /* Deal with logfile omission, if required. */
1465 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1467 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1469 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1470 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1471 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1478 static void send_packet(Ssh ssh
, int pkttype
, ...)
1482 va_start(ap1
, pkttype
);
1483 va_start(ap2
, pkttype
);
1484 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1488 ssh_free_packet(pkt
);
1491 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1495 va_start(ap1
, pkttype
);
1496 va_start(ap2
, pkttype
);
1497 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1500 s_wrpkt_defer(ssh
, pkt
);
1501 ssh_free_packet(pkt
);
1504 static int ssh_versioncmp(char *a
, char *b
)
1507 unsigned long av
, bv
;
1509 av
= strtoul(a
, &ae
, 10);
1510 bv
= strtoul(b
, &be
, 10);
1512 return (av
< bv ?
-1 : +1);
1517 av
= strtoul(ae
, &ae
, 10);
1518 bv
= strtoul(be
, &be
, 10);
1520 return (av
< bv ?
-1 : +1);
1525 * Utility routines for putting an SSH-protocol `string' and
1526 * `uint32' into a SHA state.
1529 static void sha_string(SHA_State
* s
, void *str
, int len
)
1531 unsigned char lenblk
[4];
1532 PUT_32BIT(lenblk
, len
);
1533 SHA_Bytes(s
, lenblk
, 4);
1534 SHA_Bytes(s
, str
, len
);
1537 static void sha_uint32(SHA_State
* s
, unsigned i
)
1539 unsigned char intblk
[4];
1540 PUT_32BIT(intblk
, i
);
1541 SHA_Bytes(s
, intblk
, 4);
1545 * SSH2 packet construction functions.
1547 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1549 if (pkt
->maxlen
< length
) {
1550 pkt
->maxlen
= length
+ 256;
1551 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1554 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1556 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1558 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1559 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1560 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1561 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1564 ssh2_pkt_ensure(pkt
, pkt
->length
);
1565 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1567 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1569 ssh2_pkt_adddata(pkt
, &byte
, 1);
1571 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1573 struct Packet
*pkt
= ssh_new_packet();
1575 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1578 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1580 ssh2_pkt_adddata(pkt
, &value
, 1);
1582 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1585 PUT_32BIT(x
, value
);
1586 ssh2_pkt_adddata(pkt
, x
, 4);
1588 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1590 ssh2_pkt_adduint32(pkt
, 0);
1591 pkt
->savedpos
= pkt
->length
;
1593 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1595 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1596 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1598 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1600 ssh2_pkt_adddata(pkt
, data
, len
);
1601 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1603 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1605 ssh2_pkt_addstring_start(pkt
);
1606 ssh2_pkt_addstring_str(pkt
, data
);
1608 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1611 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1612 p
= snewn(n
+ 1, unsigned char);
1614 fatalbox("out of memory");
1616 for (i
= 1; i
<= n
; i
++)
1617 p
[i
] = bignum_byte(b
, n
- i
);
1619 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1621 memmove(p
, p
+ i
, n
+ 1 - i
);
1625 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1629 p
= ssh2_mpint_fmt(b
, &len
);
1630 ssh2_pkt_addstring_start(pkt
);
1631 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1636 * Construct an SSH2 final-form packet: compress it, encrypt it,
1637 * put the MAC on it. Final packet, ready to be sent, is stored in
1638 * pkt->data. Total length is returned.
1640 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1642 int cipherblk
, maclen
, padding
, i
;
1645 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1646 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1647 pkt
->data
+ 6, pkt
->length
- 6,
1648 pkt
->nblanks
, pkt
->blanks
);
1649 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1653 * Compress packet payload.
1656 unsigned char *newpayload
;
1659 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1661 &newpayload
, &newlen
)) {
1663 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1669 * Add padding. At least four bytes, and must also bring total
1670 * length (minus MAC) up to a multiple of the block size.
1672 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1673 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1676 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1677 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1678 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1679 pkt
->data
[4] = padding
;
1680 for (i
= 0; i
< padding
; i
++)
1681 pkt
->data
[pkt
->length
+ i
] = random_byte();
1682 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1684 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1685 pkt
->length
+ padding
,
1686 ssh
->v2_outgoing_sequence
);
1687 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1690 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1691 pkt
->data
, pkt
->length
+ padding
);
1693 pkt
->encrypted_len
= pkt
->length
+ padding
;
1695 /* Ready-to-send packet starts at pkt->data. We return length. */
1696 return pkt
->length
+ padding
+ maclen
;
1700 * Routines called from the main SSH code to send packets. There
1701 * are quite a few of these, because we have two separate
1702 * mechanisms for delaying the sending of packets:
1704 * - In order to send an IGNORE message and a password message in
1705 * a single fixed-length blob, we require the ability to
1706 * concatenate the encrypted forms of those two packets _into_ a
1707 * single blob and then pass it to our <network.h> transport
1708 * layer in one go. Hence, there's a deferment mechanism which
1709 * works after packet encryption.
1711 * - In order to avoid sending any connection-layer messages
1712 * during repeat key exchange, we have to queue up any such
1713 * outgoing messages _before_ they are encrypted (and in
1714 * particular before they're allocated sequence numbers), and
1715 * then send them once we've finished.
1717 * I call these mechanisms `defer' and `queue' respectively, so as
1718 * to distinguish them reasonably easily.
1720 * The functions send_noqueue() and defer_noqueue() free the packet
1721 * structure they are passed. Every outgoing packet goes through
1722 * precisely one of these functions in its life; packets passed to
1723 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1724 * these or get queued, and then when the queue is later emptied
1725 * the packets are all passed to defer_noqueue().
1729 * Send an SSH2 packet immediately, without queuing or deferring.
1731 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1735 len
= ssh2_pkt_construct(ssh
, pkt
);
1736 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1737 if (backlog
> SSH_MAX_BACKLOG
)
1738 ssh_throttle_all(ssh
, 1, backlog
);
1740 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1741 if (!ssh
->kex_in_progress
&&
1742 ssh
->max_data_size
!= 0 &&
1743 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1744 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1746 ssh_free_packet(pkt
);
1750 * Defer an SSH2 packet.
1752 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1754 int len
= ssh2_pkt_construct(ssh
, pkt
);
1755 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1756 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1757 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1761 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1762 ssh
->deferred_len
+= len
;
1763 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1764 ssh_free_packet(pkt
);
1768 * Queue an SSH2 packet.
1770 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1772 assert(ssh
->queueing
);
1774 if (ssh
->queuelen
>= ssh
->queuesize
) {
1775 ssh
->queuesize
= ssh
->queuelen
+ 32;
1776 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1779 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1783 * Either queue or send a packet, depending on whether queueing is
1786 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1789 ssh2_pkt_queue(ssh
, pkt
);
1791 ssh2_pkt_send_noqueue(ssh
, pkt
);
1795 * Either queue or defer a packet, depending on whether queueing is
1798 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1801 ssh2_pkt_queue(ssh
, pkt
);
1803 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1807 * Send the whole deferred data block constructed by
1808 * ssh2_pkt_defer() or SSH1's defer_packet().
1810 * The expected use of the defer mechanism is that you call
1811 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1812 * not currently queueing, this simply sets up deferred_send_data
1813 * and then sends it. If we _are_ currently queueing, the calls to
1814 * ssh2_pkt_defer() put the deferred packets on to the queue
1815 * instead, and therefore ssh_pkt_defersend() has no deferred data
1816 * to send. Hence, there's no need to make it conditional on
1819 static void ssh_pkt_defersend(Ssh ssh
)
1822 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1824 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1825 sfree(ssh
->deferred_send_data
);
1826 ssh
->deferred_send_data
= NULL
;
1827 if (backlog
> SSH_MAX_BACKLOG
)
1828 ssh_throttle_all(ssh
, 1, backlog
);
1830 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1831 if (!ssh
->kex_in_progress
&&
1832 ssh
->max_data_size
!= 0 &&
1833 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1834 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1835 ssh
->deferred_data_size
= 0;
1839 * Send all queued SSH2 packets. We send them by means of
1840 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1841 * packets that needed to be lumped together.
1843 static void ssh2_pkt_queuesend(Ssh ssh
)
1847 assert(!ssh
->queueing
);
1849 for (i
= 0; i
< ssh
->queuelen
; i
++)
1850 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1853 ssh_pkt_defersend(ssh
);
1857 void bndebug(char *string
, Bignum b
)
1861 p
= ssh2_mpint_fmt(b
, &len
);
1862 debug(("%s", string
));
1863 for (i
= 0; i
< len
; i
++)
1864 debug((" %02x", p
[i
]));
1870 static void sha_mpint(SHA_State
* s
, Bignum b
)
1874 p
= ssh2_mpint_fmt(b
, &len
);
1875 sha_string(s
, p
, len
);
1880 * Packet decode functions for both SSH1 and SSH2.
1882 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1884 unsigned long value
;
1885 if (pkt
->length
- pkt
->savedpos
< 4)
1886 return 0; /* arrgh, no way to decline (FIXME?) */
1887 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1891 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1893 unsigned long value
;
1894 if (pkt
->length
- pkt
->savedpos
< 1)
1895 return 0; /* arrgh, no way to decline (FIXME?) */
1896 value
= pkt
->body
[pkt
->savedpos
] != 0;
1900 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1905 if (pkt
->length
- pkt
->savedpos
< 4)
1907 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1912 if (pkt
->length
- pkt
->savedpos
< *length
)
1914 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1915 pkt
->savedpos
+= *length
;
1917 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1919 if (pkt
->length
- pkt
->savedpos
< length
)
1921 pkt
->savedpos
+= length
;
1922 return pkt
->body
+ (pkt
->savedpos
- length
);
1924 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1925 unsigned char **keystr
)
1929 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1930 pkt
->length
- pkt
->savedpos
,
1937 assert(pkt
->savedpos
< pkt
->length
);
1941 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1946 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1947 pkt
->length
- pkt
->savedpos
, &b
);
1955 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1961 ssh_pkt_getstring(pkt
, &p
, &length
);
1966 b
= bignum_from_bytes((unsigned char *)p
, length
);
1971 * Helper function to add an SSH2 signature blob to a packet.
1972 * Expects to be shown the public key blob as well as the signature
1973 * blob. Normally works just like ssh2_pkt_addstring, but will
1974 * fiddle with the signature packet if necessary for
1975 * BUG_SSH2_RSA_PADDING.
1977 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1978 void *pkblob_v
, int pkblob_len
,
1979 void *sigblob_v
, int sigblob_len
)
1981 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1982 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1984 /* dmemdump(pkblob, pkblob_len); */
1985 /* dmemdump(sigblob, sigblob_len); */
1988 * See if this is in fact an ssh-rsa signature and a buggy
1989 * server; otherwise we can just do this the easy way.
1991 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1992 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1993 int pos
, len
, siglen
;
1996 * Find the byte length of the modulus.
1999 pos
= 4+7; /* skip over "ssh-rsa" */
2000 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2001 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2002 pos
+= 4; /* find modulus itself */
2003 while (len
> 0 && pkblob
[pos
] == 0)
2005 /* debug(("modulus length is %d\n", len)); */
2008 * Now find the signature integer.
2010 pos
= 4+7; /* skip over "ssh-rsa" */
2011 siglen
= GET_32BIT(sigblob
+pos
);
2012 /* debug(("signature length is %d\n", siglen)); */
2014 if (len
!= siglen
) {
2015 unsigned char newlen
[4];
2016 ssh2_pkt_addstring_start(pkt
);
2017 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2018 /* dmemdump(sigblob, pos); */
2019 pos
+= 4; /* point to start of actual sig */
2020 PUT_32BIT(newlen
, len
);
2021 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2022 /* dmemdump(newlen, 4); */
2024 while (len
-- > siglen
) {
2025 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2026 /* dmemdump(newlen, 1); */
2028 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2029 /* dmemdump(sigblob+pos, siglen); */
2033 /* Otherwise fall through and do it the easy way. */
2036 ssh2_pkt_addstring_start(pkt
);
2037 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2041 * Examine the remote side's version string and compare it against
2042 * a list of known buggy implementations.
2044 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2046 char *imp
; /* pointer to implementation part */
2048 imp
+= strcspn(imp
, "-");
2050 imp
+= strcspn(imp
, "-");
2053 ssh
->remote_bugs
= 0;
2055 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2056 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2057 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2058 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2059 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2060 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2062 * These versions don't support SSH1_MSG_IGNORE, so we have
2063 * to use a different defence against password length
2066 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2067 logevent("We believe remote version has SSH1 ignore bug");
2070 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2071 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2072 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2074 * These versions need a plain password sent; they can't
2075 * handle having a null and a random length of data after
2078 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2079 logevent("We believe remote version needs a plain SSH1 password");
2082 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2083 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2084 (!strcmp(imp
, "Cisco-1.25")))) {
2086 * These versions apparently have no clue whatever about
2087 * RSA authentication and will panic and die if they see
2088 * an AUTH_RSA message.
2090 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2091 logevent("We believe remote version can't handle RSA authentication");
2094 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2095 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2096 !wc_match("* VShell", imp
) &&
2097 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2098 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2099 wc_match("2.1 *", imp
)))) {
2101 * These versions have the HMAC bug.
2103 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2104 logevent("We believe remote version has SSH2 HMAC bug");
2107 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2108 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2109 !wc_match("* VShell", imp
) &&
2110 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2112 * These versions have the key-derivation bug (failing to
2113 * include the literal shared secret in the hashes that
2114 * generate the keys).
2116 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2117 logevent("We believe remote version has SSH2 key-derivation bug");
2120 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2121 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2122 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2123 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2125 * These versions have the SSH2 RSA padding bug.
2127 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2128 logevent("We believe remote version has SSH2 RSA padding bug");
2131 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2132 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2133 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2135 * These versions have the SSH2 session-ID bug in
2136 * public-key authentication.
2138 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2139 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2142 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2143 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2144 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2145 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2146 wc_match("Sun_SSH_1.0", imp
) ||
2147 wc_match("Sun_SSH_1.0.1", imp
)))) {
2149 * These versions have the SSH2 rekey bug.
2151 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2152 logevent("We believe remote version has SSH2 rekey bug");
2157 * The `software version' part of an SSH version string is required
2158 * to contain no spaces or minus signs.
2160 static void ssh_fix_verstring(char *str
)
2162 /* Eat "SSH-<protoversion>-". */
2163 assert(*str
== 'S'); str
++;
2164 assert(*str
== 'S'); str
++;
2165 assert(*str
== 'H'); str
++;
2166 assert(*str
== '-'); str
++;
2167 while (*str
&& *str
!= '-') str
++;
2168 assert(*str
== '-'); str
++;
2170 /* Convert minus signs and spaces in the remaining string into
2173 if (*str
== '-' || *str
== ' ')
2179 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2181 struct do_ssh_init_state
{
2189 crState(do_ssh_init_state
);
2191 crBegin(ssh
->do_ssh_init_crstate
);
2193 /* Search for the string "SSH-" in the input. */
2196 static const int transS
[] = { 1, 2, 2, 1 };
2197 static const int transH
[] = { 0, 0, 3, 0 };
2198 static const int transminus
[] = { 0, 0, 0, -1 };
2200 s
->i
= transS
[s
->i
];
2202 s
->i
= transH
[s
->i
];
2204 s
->i
= transminus
[s
->i
];
2209 crReturn(1); /* get another character */
2213 s
->vstring
= snewn(s
->vstrsize
, char);
2214 strcpy(s
->vstring
, "SSH-");
2218 crReturn(1); /* get another char */
2219 if (s
->vslen
>= s
->vstrsize
- 1) {
2221 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2223 s
->vstring
[s
->vslen
++] = c
;
2226 s
->version
[s
->i
] = '\0';
2228 } else if (s
->i
< sizeof(s
->version
) - 1)
2229 s
->version
[s
->i
++] = c
;
2230 } else if (c
== '\012')
2234 ssh
->agentfwd_enabled
= FALSE
;
2235 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2237 s
->vstring
[s
->vslen
] = 0;
2238 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2241 vlog
= snewn(20 + s
->vslen
, char);
2242 sprintf(vlog
, "Server version: %s", s
->vstring
);
2246 ssh_detect_bugs(ssh
, s
->vstring
);
2249 * Decide which SSH protocol version to support.
2252 /* Anything strictly below "2.0" means protocol 1 is supported. */
2253 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2254 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2255 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2257 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2258 bombout(("SSH protocol version 1 required by user but not provided by server"));
2261 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2262 bombout(("SSH protocol version 2 required by user but not provided by server"));
2269 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2271 * Construct a v2 version string.
2273 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2277 * Construct a v1 version string.
2279 verstring
= dupprintf("SSH-%s-%s\012",
2280 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2281 s
->version
: "1.5"),
2286 ssh_fix_verstring(verstring
);
2288 if (ssh
->version
== 2) {
2290 * Hash our version string and their version string.
2292 SHA_Init(&ssh
->exhashbase
);
2293 sha_string(&ssh
->exhashbase
, verstring
,
2294 strcspn(verstring
, "\015\012"));
2295 sha_string(&ssh
->exhashbase
, s
->vstring
,
2296 strcspn(s
->vstring
, "\015\012"));
2299 * Initialise SSHv2 protocol.
2301 ssh
->protocol
= ssh2_protocol
;
2302 ssh2_protocol_setup(ssh
);
2303 ssh
->s_rdpkt
= ssh2_rdpkt
;
2306 * Initialise SSHv1 protocol.
2308 ssh
->protocol
= ssh1_protocol
;
2309 ssh1_protocol_setup(ssh
);
2310 ssh
->s_rdpkt
= ssh1_rdpkt
;
2312 logeventf(ssh
, "We claim version: %.*s",
2313 strcspn(verstring
, "\015\012"), verstring
);
2314 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2318 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2320 update_specials_menu(ssh
->frontend
);
2321 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2322 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2329 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2331 crBegin(ssh
->ssh_gotdata_crstate
);
2334 * To begin with, feed the characters one by one to the
2335 * protocol initialisation / selection function do_ssh_init().
2336 * When that returns 0, we're done with the initial greeting
2337 * exchange and can move on to packet discipline.
2340 int ret
; /* need not be kept across crReturn */
2342 crReturnV
; /* more data please */
2343 ret
= do_ssh_init(ssh
, *data
);
2351 * We emerge from that loop when the initial negotiation is
2352 * over and we have selected an s_rdpkt function. Now pass
2353 * everything to s_rdpkt, and then pass the resulting packets
2354 * to the proper protocol handler.
2359 while (datalen
> 0) {
2360 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2362 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2363 ssh_free_packet(pktin
);
2365 if (ssh
->state
== SSH_STATE_CLOSED
)
2373 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2376 struct ssh_channel
*c
;
2378 ssh
->state
= SSH_STATE_CLOSED
;
2383 notify_remote_exit(ssh
->frontend
);
2388 * Now we must shut down any port and X forwardings going
2389 * through this connection.
2391 if (ssh
->channels
) {
2392 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2395 x11_close(c
->u
.x11
.s
);
2398 pfd_close(c
->u
.pfd
.s
);
2401 del234(ssh
->channels
, c
);
2402 if (ssh
->version
== 2)
2403 bufchain_clear(&c
->v
.v2
.outbuffer
);
2411 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2414 Ssh ssh
= (Ssh
) plug
;
2415 int need_notify
= ssh_do_close(ssh
, FALSE
);
2417 if (!error_msg
&& !ssh
->close_expected
) {
2418 error_msg
= "Server unexpectedly closed network connection";
2422 /* A socket error has occurred. */
2423 logevent(error_msg
);
2424 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2426 logevent("Server closed network connection");
2429 notify_remote_exit(ssh
->frontend
);
2433 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2435 Ssh ssh
= (Ssh
) plug
;
2436 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2437 if (ssh
->state
== SSH_STATE_CLOSED
) {
2438 ssh_do_close(ssh
, TRUE
);
2444 static void ssh_sent(Plug plug
, int bufsize
)
2446 Ssh ssh
= (Ssh
) plug
;
2448 * If the send backlog on the SSH socket itself clears, we
2449 * should unthrottle the whole world if it was throttled.
2451 if (bufsize
< SSH_MAX_BACKLOG
)
2452 ssh_throttle_all(ssh
, 0, bufsize
);
2456 * Connect to specified host and port.
2457 * Returns an error message, or NULL on success.
2458 * Also places the canonical host name into `realhost'. It must be
2459 * freed by the caller.
2461 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2462 char **realhost
, int nodelay
, int keepalive
)
2464 static const struct plug_function_table fn_table
= {
2474 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2475 if (!ssh
->savedhost
)
2476 fatalbox("Out of memory");
2477 strcpy(ssh
->savedhost
, host
);
2480 port
= 22; /* default ssh port */
2481 ssh
->savedport
= port
;
2486 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2487 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2488 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2489 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2490 ssh
->cfg
.addressfamily
);
2491 if ((err
= sk_addr_error(addr
)) != NULL
) {
2501 sk_getaddr(addr
, addrbuf
, 100);
2502 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2504 ssh
->fn
= &fn_table
;
2505 ssh
->s
= new_connection(addr
, *realhost
, port
,
2506 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2507 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2509 notify_remote_exit(ssh
->frontend
);
2517 * Throttle or unthrottle the SSH connection.
2519 static void ssh1_throttle(Ssh ssh
, int adjust
)
2521 int old_count
= ssh
->v1_throttle_count
;
2522 ssh
->v1_throttle_count
+= adjust
;
2523 assert(ssh
->v1_throttle_count
>= 0);
2524 if (ssh
->v1_throttle_count
&& !old_count
) {
2525 sk_set_frozen(ssh
->s
, 1);
2526 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2527 sk_set_frozen(ssh
->s
, 0);
2532 * Throttle or unthrottle _all_ local data streams (for when sends
2533 * on the SSH connection itself back up).
2535 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2538 struct ssh_channel
*c
;
2540 if (enable
== ssh
->throttled_all
)
2542 ssh
->throttled_all
= enable
;
2543 ssh
->overall_bufsize
= bufsize
;
2546 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2548 case CHAN_MAINSESSION
:
2550 * This is treated separately, outside the switch.
2554 x11_override_throttle(c
->u
.x11
.s
, enable
);
2557 /* Agent channels require no buffer management. */
2560 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2567 * Username and password input, abstracted off into routines
2568 * reusable in several places - even between SSH1 and SSH2.
2571 /* Set up a username or password input loop on a given buffer. */
2572 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2574 ssh
->userpass_input_buffer
= buffer
;
2575 ssh
->userpass_input_buflen
= buflen
;
2576 ssh
->userpass_input_bufpos
= 0;
2577 ssh
->userpass_input_echo
= echo
;
2581 * Process some terminal data in the course of username/password
2582 * input. Returns >0 for success (line of input returned in
2583 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2584 * for inconclusive (keep waiting for more input please).
2586 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2591 switch (c
= *in
++) {
2594 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2595 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2600 if (ssh
->userpass_input_bufpos
> 0) {
2601 if (ssh
->userpass_input_echo
)
2602 c_write_str(ssh
, "\b \b");
2603 ssh
->userpass_input_bufpos
--;
2608 while (ssh
->userpass_input_bufpos
> 0) {
2609 if (ssh
->userpass_input_echo
)
2610 c_write_str(ssh
, "\b \b");
2611 ssh
->userpass_input_bufpos
--;
2620 * This simplistic check for printability is disabled
2621 * when we're doing password input, because some people
2622 * have control characters in their passwords.o
2624 if ((!ssh
->userpass_input_echo
||
2625 (c
>= ' ' && c
<= '~') ||
2626 ((unsigned char) c
>= 160))
2627 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2628 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2629 if (ssh
->userpass_input_echo
)
2630 c_write(ssh
, &c
, 1);
2638 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2640 Ssh ssh
= (Ssh
) sshv
;
2642 ssh
->agent_response
= reply
;
2643 ssh
->agent_response_len
= replylen
;
2645 if (ssh
->version
== 1)
2646 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2648 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2651 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2653 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2655 void *sentreply
= reply
;
2658 /* Fake SSH_AGENT_FAILURE. */
2659 sentreply
= "\0\0\0\1\5";
2662 if (ssh
->version
== 2) {
2663 ssh2_add_channel_data(c
, sentreply
, replylen
);
2666 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2667 PKT_INT
, c
->remoteid
,
2670 PKT_DATA
, sentreply
, replylen
,
2679 * Handle the key exchange and user authentication phases.
2681 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2682 struct Packet
*pktin
)
2685 unsigned char cookie
[8], *ptr
;
2686 struct RSAKey servkey
, hostkey
;
2687 struct MD5Context md5c
;
2688 struct do_ssh1_login_state
{
2690 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2691 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2692 int tried_publickey
, tried_agent
;
2693 int tis_auth_refused
, ccard_auth_refused
;
2694 unsigned char session_id
[16];
2697 void *publickey_blob
;
2698 int publickey_bloblen
;
2704 unsigned char request
[5], *response
, *p
;
2713 crState(do_ssh1_login_state
);
2715 crBegin(ssh
->do_ssh1_login_crstate
);
2720 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2721 bombout(("Public key packet not received"));
2725 logevent("Received public keys");
2727 ptr
= ssh_pkt_getdata(pktin
, 8);
2729 bombout(("SSH1 public key packet stopped before random cookie"));
2732 memcpy(cookie
, ptr
, 8);
2734 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2735 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2736 bombout(("Failed to read SSH1 public keys from public key packet"));
2741 * Log the host key fingerprint.
2745 logevent("Host key fingerprint is:");
2746 strcpy(logmsg
, " ");
2747 hostkey
.comment
= NULL
;
2748 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2749 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2753 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2754 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2755 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2757 ssh
->v1_local_protoflags
=
2758 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2759 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2762 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2763 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2764 MD5Update(&md5c
, cookie
, 8);
2765 MD5Final(s
->session_id
, &md5c
);
2767 for (i
= 0; i
< 32; i
++)
2768 ssh
->session_key
[i
] = random_byte();
2771 * Verify that the `bits' and `bytes' parameters match.
2773 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2774 servkey
.bits
> servkey
.bytes
* 8) {
2775 bombout(("SSH1 public keys were badly formatted"));
2779 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2781 s
->rsabuf
= snewn(s
->len
, unsigned char);
2783 fatalbox("Out of memory");
2786 * Verify the host key.
2790 * First format the key into a string.
2792 int len
= rsastr_len(&hostkey
);
2793 char fingerprint
[100];
2794 char *keystr
= snewn(len
, char);
2796 fatalbox("Out of memory");
2797 rsastr_fmt(keystr
, &hostkey
);
2798 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2799 verify_ssh_host_key(ssh
->frontend
,
2800 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2805 for (i
= 0; i
< 32; i
++) {
2806 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2808 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2811 if (hostkey
.bytes
> servkey
.bytes
) {
2812 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2814 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2816 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2818 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2821 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2825 logevent("Encrypted session key");
2828 int cipher_chosen
= 0, warn
= 0;
2829 char *cipher_string
= NULL
;
2831 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2832 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2833 if (next_cipher
== CIPHER_WARN
) {
2834 /* If/when we choose a cipher, warn about it */
2836 } else if (next_cipher
== CIPHER_AES
) {
2837 /* XXX Probably don't need to mention this. */
2838 logevent("AES not supported in SSH1, skipping");
2840 switch (next_cipher
) {
2841 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2842 cipher_string
= "3DES"; break;
2843 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2844 cipher_string
= "Blowfish"; break;
2845 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2846 cipher_string
= "single-DES"; break;
2848 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2852 if (!cipher_chosen
) {
2853 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2854 bombout(("Server violates SSH 1 protocol by not "
2855 "supporting 3DES encryption"));
2857 /* shouldn't happen */
2858 bombout(("No supported ciphers found"));
2862 /* Warn about chosen cipher if necessary. */
2864 sk_set_frozen(ssh
->s
, 1);
2865 askalg(ssh
->frontend
, "cipher", cipher_string
);
2866 sk_set_frozen(ssh
->s
, 0);
2870 switch (s
->cipher_type
) {
2871 case SSH_CIPHER_3DES
:
2872 logevent("Using 3DES encryption");
2874 case SSH_CIPHER_DES
:
2875 logevent("Using single-DES encryption");
2877 case SSH_CIPHER_BLOWFISH
:
2878 logevent("Using Blowfish encryption");
2882 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2883 PKT_CHAR
, s
->cipher_type
,
2884 PKT_DATA
, cookie
, 8,
2885 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2886 PKT_DATA
, s
->rsabuf
, s
->len
,
2887 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2889 logevent("Trying to enable encryption...");
2893 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2894 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2896 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2897 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2898 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2900 ssh
->crcda_ctx
= crcda_make_context();
2901 logevent("Installing CRC compensation attack detector");
2903 if (servkey
.modulus
) {
2904 sfree(servkey
.modulus
);
2905 servkey
.modulus
= NULL
;
2907 if (servkey
.exponent
) {
2908 sfree(servkey
.exponent
);
2909 servkey
.exponent
= NULL
;
2911 if (hostkey
.modulus
) {
2912 sfree(hostkey
.modulus
);
2913 hostkey
.modulus
= NULL
;
2915 if (hostkey
.exponent
) {
2916 sfree(hostkey
.exponent
);
2917 hostkey
.exponent
= NULL
;
2921 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2922 bombout(("Encryption not successfully enabled"));
2926 logevent("Successfully started encryption");
2930 if (!*ssh
->cfg
.username
) {
2931 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2932 if (!ssh_get_line("login as: ",
2933 s
->username
, sizeof(s
->username
), FALSE
)) {
2935 * get_line failed to get a username.
2938 logevent("No username provided. Abandoning session.");
2939 ssh
->close_expected
= TRUE
;
2940 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2944 int ret
; /* need not be kept over crReturn */
2945 c_write_str(ssh
, "login as: ");
2948 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2950 crWaitUntil(!pktin
);
2951 ret
= process_userpass_input(ssh
, in
, inlen
);
2955 c_write_str(ssh
, "\r\n");
2958 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2959 s
->username
[sizeof(s
->username
)-1] = '\0';
2962 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2964 char userlog
[22 + sizeof(s
->username
)];
2965 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2967 if (flags
& FLAG_INTERACTIVE
&&
2968 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2969 strcat(userlog
, "\r\n");
2970 c_write_str(ssh
, userlog
);
2977 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2978 /* We must not attempt PK auth. Pretend we've already tried it. */
2979 s
->tried_publickey
= s
->tried_agent
= 1;
2981 s
->tried_publickey
= s
->tried_agent
= 0;
2983 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2984 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2985 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2986 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2987 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2988 s
->publickey_blob
= NULL
;
2990 s
->publickey_blob
= NULL
;
2992 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2993 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2995 if (agent_exists() && !s
->tried_agent
) {
2997 * Attempt RSA authentication using Pageant.
3003 logevent("Pageant is running. Requesting keys.");
3005 /* Request the keys held by the agent. */
3006 PUT_32BIT(s
->request
, 1);
3007 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3008 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3009 ssh_agent_callback
, ssh
)) {
3013 bombout(("Unexpected data from server while waiting"
3014 " for agent response"));
3017 } while (pktin
|| inlen
> 0);
3018 r
= ssh
->agent_response
;
3019 s
->responselen
= ssh
->agent_response_len
;
3021 s
->response
= (unsigned char *) r
;
3022 if (s
->response
&& s
->responselen
>= 5 &&
3023 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3024 s
->p
= s
->response
+ 5;
3025 s
->nkeys
= GET_32BIT(s
->p
);
3029 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
3032 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3035 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
3038 if (s
->publickey_blob
&&
3039 !memcmp(s
->p
, s
->publickey_blob
,
3040 s
->publickey_bloblen
)) {
3041 logevent("This key matches configured key file");
3042 s
->tried_publickey
= 1;
3047 do { /* do while (0) to make breaking easy */
3048 n
= ssh1_read_bignum
3049 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3054 n
= ssh1_read_bignum
3055 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3060 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3062 s
->commentlen
= GET_32BIT(s
->p
);
3064 if (s
->responselen
- (s
->p
-s
->response
) <
3067 s
->commentp
= (char *)s
->p
;
3068 s
->p
+= s
->commentlen
;
3072 logevent("Pageant key list packet was truncated");
3076 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3077 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3079 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3080 logevent("Key refused");
3083 logevent("Received RSA challenge");
3084 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3085 bombout(("Server's RSA challenge was badly formatted"));
3090 char *agentreq
, *q
, *ret
;
3093 len
= 1 + 4; /* message type, bit count */
3094 len
+= ssh1_bignum_length(s
->key
.exponent
);
3095 len
+= ssh1_bignum_length(s
->key
.modulus
);
3096 len
+= ssh1_bignum_length(s
->challenge
);
3097 len
+= 16; /* session id */
3098 len
+= 4; /* response format */
3099 agentreq
= snewn(4 + len
, char);
3100 PUT_32BIT(agentreq
, len
);
3102 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3103 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3105 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3106 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3107 q
+= ssh1_write_bignum(q
, s
->challenge
);
3108 memcpy(q
, s
->session_id
, 16);
3110 PUT_32BIT(q
, 1); /* response format */
3111 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3112 ssh_agent_callback
, ssh
)) {
3117 bombout(("Unexpected data from server"
3118 " while waiting for agent"
3122 } while (pktin
|| inlen
> 0);
3123 vret
= ssh
->agent_response
;
3124 retlen
= ssh
->agent_response_len
;
3129 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3130 logevent("Sending Pageant's response");
3131 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3132 PKT_DATA
, ret
+ 5, 16,
3136 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3138 ("Pageant's response accepted");
3139 if (flags
& FLAG_VERBOSE
) {
3140 c_write_str(ssh
, "Authenticated using"
3142 c_write(ssh
, s
->commentp
,
3144 c_write_str(ssh
, "\" from agent\r\n");
3149 ("Pageant's response not accepted");
3152 ("Pageant failed to answer challenge");
3156 logevent("No reply received from Pageant");
3159 freebn(s
->key
.exponent
);
3160 freebn(s
->key
.modulus
);
3161 freebn(s
->challenge
);
3170 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3171 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3173 if (ssh
->cfg
.try_tis_auth
&&
3174 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3175 !s
->tis_auth_refused
) {
3176 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3177 logevent("Requested TIS authentication");
3178 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3180 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3181 logevent("TIS authentication declined");
3182 if (flags
& FLAG_INTERACTIVE
)
3183 c_write_str(ssh
, "TIS authentication refused.\r\n");
3184 s
->tis_auth_refused
= 1;
3190 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3192 bombout(("TIS challenge packet was badly formed"));
3195 logevent("Received TIS challenge");
3196 if (challengelen
> sizeof(s
->prompt
) - 1)
3197 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3198 memcpy(s
->prompt
, challenge
, challengelen
);
3199 /* Prompt heuristic comes from OpenSSH */
3200 strncpy(s
->prompt
+ challengelen
,
3201 memchr(s
->prompt
, '\n', challengelen
) ?
3202 "": "\r\nResponse: ",
3203 (sizeof s
->prompt
) - challengelen
);
3204 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3207 if (ssh
->cfg
.try_tis_auth
&&
3208 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3209 !s
->ccard_auth_refused
) {
3210 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3211 logevent("Requested CryptoCard authentication");
3212 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3214 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3215 logevent("CryptoCard authentication declined");
3216 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3217 s
->ccard_auth_refused
= 1;
3223 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3225 bombout(("CryptoCard challenge packet was badly formed"));
3228 logevent("Received CryptoCard challenge");
3229 if (challengelen
> sizeof(s
->prompt
) - 1)
3230 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3231 memcpy(s
->prompt
, challenge
, challengelen
);
3232 strncpy(s
->prompt
+ challengelen
,
3233 memchr(s
->prompt
, '\n', challengelen
) ?
3234 "" : "\r\nResponse: ",
3235 sizeof(s
->prompt
) - challengelen
);
3236 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3239 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3240 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3241 s
->username
, ssh
->savedhost
);
3243 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3244 char *comment
= NULL
;
3247 if (flags
& FLAG_VERBOSE
)
3248 c_write_str(ssh
, "Trying public key authentication.\r\n");
3249 logeventf(ssh
, "Trying public key \"%s\"",
3250 filename_to_str(&ssh
->cfg
.keyfile
));
3251 type
= key_type(&ssh
->cfg
.keyfile
);
3252 if (type
!= SSH_KEYTYPE_SSH1
) {
3253 sprintf(msgbuf
, "Key is of wrong type (%s)",
3254 key_type_to_str(type
));
3256 c_write_str(ssh
, msgbuf
);
3257 c_write_str(ssh
, "\r\n");
3258 s
->tried_publickey
= 1;
3261 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3262 if (flags
& FLAG_VERBOSE
)
3263 c_write_str(ssh
, "No passphrase required.\r\n");
3266 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3271 * Show password prompt, having first obtained it via a TIS
3272 * or CryptoCard exchange if we're doing TIS or CryptoCard
3276 if (!ssh_get_line(s
->prompt
, s
->password
,
3277 sizeof(s
->password
), TRUE
)) {
3279 * get_line failed to get a password (for example
3280 * because one was supplied on the command line
3281 * which has already failed to work). Terminate.
3283 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3284 PKT_STR
, "No more passwords available to try",
3286 logevent("Unable to authenticate");
3287 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3288 ssh
->close_expected
= TRUE
;
3289 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3293 /* Prompt may have come from server. We've munged it a bit, so
3294 * we know it to be zero-terminated at least once. */
3295 int ret
; /* need not be saved over crReturn */
3296 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3299 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3301 crWaitUntil(!pktin
);
3302 ret
= process_userpass_input(ssh
, in
, inlen
);
3306 c_write_str(ssh
, "\r\n");
3310 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3312 * Try public key authentication with the specified
3315 s
->tried_publickey
= 1;
3318 const char *error
= NULL
;
3319 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3322 c_write_str(ssh
, "Couldn't load private key from ");
3323 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3324 c_write_str(ssh
, " (");
3325 c_write_str(ssh
, error
);
3326 c_write_str(ssh
, ").\r\n");
3327 continue; /* go and try password */
3330 c_write_str(ssh
, "Wrong passphrase.\r\n");
3331 s
->tried_publickey
= 0;
3332 continue; /* try again */
3337 * Send a public key attempt.
3339 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3340 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3343 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3344 c_write_str(ssh
, "Server refused our public key.\r\n");
3345 continue; /* go and try password */
3347 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3348 bombout(("Bizarre response to offer of public key"));
3354 unsigned char buffer
[32];
3355 Bignum challenge
, response
;
3357 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3358 bombout(("Server's RSA challenge was badly formatted"));
3361 response
= rsadecrypt(challenge
, &s
->key
);
3362 freebn(s
->key
.private_exponent
);/* burn the evidence */
3364 for (i
= 0; i
< 32; i
++) {
3365 buffer
[i
] = bignum_byte(response
, 31 - i
);
3369 MD5Update(&md5c
, buffer
, 32);
3370 MD5Update(&md5c
, s
->session_id
, 16);
3371 MD5Final(buffer
, &md5c
);
3373 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3374 PKT_DATA
, buffer
, 16, PKT_END
);
3381 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3382 if (flags
& FLAG_VERBOSE
)
3383 c_write_str(ssh
, "Failed to authenticate with"
3384 " our public key.\r\n");
3385 continue; /* go and try password */
3386 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3387 bombout(("Bizarre response to RSA authentication response"));
3391 break; /* we're through! */
3393 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3395 * Defence against traffic analysis: we send a
3396 * whole bunch of packets containing strings of
3397 * different lengths. One of these strings is the
3398 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3399 * The others are all random data in
3400 * SSH1_MSG_IGNORE packets. This way a passive
3401 * listener can't tell which is the password, and
3402 * hence can't deduce the password length.
3404 * Anybody with a password length greater than 16
3405 * bytes is going to have enough entropy in their
3406 * password that a listener won't find it _that_
3407 * much help to know how long it is. So what we'll
3410 * - if password length < 16, we send 15 packets
3411 * containing string lengths 1 through 15
3413 * - otherwise, we let N be the nearest multiple
3414 * of 8 below the password length, and send 8
3415 * packets containing string lengths N through
3416 * N+7. This won't obscure the order of
3417 * magnitude of the password length, but it will
3418 * introduce a bit of extra uncertainty.
3420 * A few servers (the old 1.2.18 through 1.2.22)
3421 * can't deal with SSH1_MSG_IGNORE. For these
3422 * servers, we need an alternative defence. We make
3423 * use of the fact that the password is interpreted
3424 * as a C string: so we can append a NUL, then some
3427 * One server (a Cisco one) can deal with neither
3428 * SSH1_MSG_IGNORE _nor_ a padded password string.
3429 * For this server we are left with no defences
3430 * against password length sniffing.
3432 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3434 * The server can deal with SSH1_MSG_IGNORE, so
3435 * we can use the primary defence.
3437 int bottom
, top
, pwlen
, i
;
3440 pwlen
= strlen(s
->password
);
3442 bottom
= 0; /* zero length passwords are OK! :-) */
3445 bottom
= pwlen
& ~7;
3449 assert(pwlen
>= bottom
&& pwlen
<= top
);
3451 randomstr
= snewn(top
+ 1, char);
3453 for (i
= bottom
; i
<= top
; i
++) {
3455 defer_packet(ssh
, s
->pwpkt_type
,
3456 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3457 PKTT_OTHER
, PKT_END
);
3459 for (j
= 0; j
< i
; j
++) {
3461 randomstr
[j
] = random_byte();
3462 } while (randomstr
[j
] == '\0');
3464 randomstr
[i
] = '\0';
3465 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3466 PKT_STR
, randomstr
, PKT_END
);
3469 logevent("Sending password with camouflage packets");
3470 ssh_pkt_defersend(ssh
);
3473 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3475 * The server can't deal with SSH1_MSG_IGNORE
3476 * but can deal with padded passwords, so we
3477 * can use the secondary defence.
3483 len
= strlen(s
->password
);
3484 if (len
< sizeof(string
)) {
3486 strcpy(string
, s
->password
);
3487 len
++; /* cover the zero byte */
3488 while (len
< sizeof(string
)) {
3489 string
[len
++] = (char) random_byte();
3494 logevent("Sending length-padded password");
3495 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3496 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3497 PKTT_OTHER
, PKT_END
);
3500 * The server has _both_
3501 * BUG_CHOKES_ON_SSH1_IGNORE and
3502 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3503 * therefore nothing we can do.
3506 len
= strlen(s
->password
);
3507 logevent("Sending unpadded password");
3508 send_packet(ssh
, s
->pwpkt_type
,
3509 PKTT_PASSWORD
, PKT_INT
, len
,
3510 PKT_DATA
, s
->password
, len
,
3511 PKTT_OTHER
, PKT_END
);
3514 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3515 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3518 logevent("Sent password");
3519 memset(s
->password
, 0, strlen(s
->password
));
3521 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3522 if (flags
& FLAG_VERBOSE
)
3523 c_write_str(ssh
, "Access denied\r\n");
3524 logevent("Authentication refused");
3525 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3526 bombout(("Strange packet received, type %d", pktin
->type
));
3531 logevent("Authentication successful");
3536 void sshfwd_close(struct ssh_channel
*c
)
3540 if (ssh
->state
!= SSH_STATE_SESSION
) {
3541 assert(ssh
->state
== SSH_STATE_CLOSED
);
3545 if (c
&& !c
->closes
) {
3547 * If the channel's remoteid is -1, we have sent
3548 * CHANNEL_OPEN for this channel, but it hasn't even been
3549 * acknowledged by the server. So we must set a close flag
3550 * on it now, and then when the server acks the channel
3551 * open, we can close it then.
3553 if (((int)c
->remoteid
) != -1) {
3554 if (ssh
->version
== 1) {
3555 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3558 struct Packet
*pktout
;
3559 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3560 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3561 ssh2_pkt_send(ssh
, pktout
);
3564 c
->closes
= 1; /* sent MSG_CLOSE */
3565 if (c
->type
== CHAN_X11
) {
3567 logevent("Forwarded X11 connection terminated");
3568 } else if (c
->type
== CHAN_SOCKDATA
||
3569 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3571 logevent("Forwarded port closed");
3576 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3580 if (ssh
->state
!= SSH_STATE_SESSION
) {
3581 assert(ssh
->state
== SSH_STATE_CLOSED
);
3585 if (ssh
->version
== 1) {
3586 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3587 PKT_INT
, c
->remoteid
,
3589 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3590 PKTT_OTHER
, PKT_END
);
3592 * In SSH1 we can return 0 here - implying that forwarded
3593 * connections are never individually throttled - because
3594 * the only circumstance that can cause throttling will be
3595 * the whole SSH connection backing up, in which case
3596 * _everything_ will be throttled as a whole.
3600 ssh2_add_channel_data(c
, buf
, len
);
3601 return ssh2_try_send(c
);
3605 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3609 if (ssh
->state
!= SSH_STATE_SESSION
) {
3610 assert(ssh
->state
== SSH_STATE_CLOSED
);
3614 if (ssh
->version
== 1) {
3615 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3616 c
->v
.v1
.throttling
= 0;
3617 ssh1_throttle(ssh
, -1);
3620 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3624 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3626 struct queued_handler
*qh
= ssh
->qhead
;
3630 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3633 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3634 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3637 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3638 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3642 ssh
->qhead
= qh
->next
;
3644 if (ssh
->qhead
->msg1
> 0) {
3645 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3646 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3648 if (ssh
->qhead
->msg2
> 0) {
3649 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3650 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3653 ssh
->qhead
= ssh
->qtail
= NULL
;
3654 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3657 qh
->handler(ssh
, pktin
, qh
->ctx
);
3662 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3663 chandler_fn_t handler
, void *ctx
)
3665 struct queued_handler
*qh
;
3667 qh
= snew(struct queued_handler
);
3670 qh
->handler
= handler
;
3674 if (ssh
->qtail
== NULL
) {
3678 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3679 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3682 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3683 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3686 ssh
->qtail
->next
= qh
;
3691 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3693 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3695 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3696 SSH2_MSG_REQUEST_SUCCESS
)) {
3697 logeventf(ssh
, "Remote port forwarding from %s enabled",
3700 logeventf(ssh
, "Remote port forwarding from %s refused",
3703 rpf
= del234(ssh
->rportfwds
, pf
);
3709 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3711 const char *portfwd_strptr
= cfg
->portfwd
;
3712 struct ssh_portfwd
*epf
;
3715 if (!ssh
->portfwds
) {
3716 ssh
->portfwds
= newtree234(ssh_portcmp
);
3719 * Go through the existing port forwardings and tag them
3720 * with status==DESTROY. Any that we want to keep will be
3721 * re-enabled (status==KEEP) as we go through the
3722 * configuration and find out which bits are the same as
3725 struct ssh_portfwd
*epf
;
3727 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3728 epf
->status
= DESTROY
;
3731 while (*portfwd_strptr
) {
3732 char address_family
, type
;
3733 int sport
,dport
,sserv
,dserv
;
3734 char sports
[256], dports
[256], saddr
[256], host
[256];
3737 address_family
= 'A';
3739 if (*portfwd_strptr
== 'A' ||
3740 *portfwd_strptr
== '4' ||
3741 *portfwd_strptr
== '6')
3742 address_family
= *portfwd_strptr
++;
3743 if (*portfwd_strptr
== 'L' ||
3744 *portfwd_strptr
== 'R' ||
3745 *portfwd_strptr
== 'D')
3746 type
= *portfwd_strptr
++;
3751 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3752 if (*portfwd_strptr
== ':') {
3754 * We've seen a colon in the middle of the
3755 * source port number. This means that
3756 * everything we've seen until now is the
3757 * source _address_, so we'll move it into
3758 * saddr and start sports from the beginning
3763 if (ssh
->version
== 1 && type
== 'R') {
3764 logeventf(ssh
, "SSH1 cannot handle remote source address "
3765 "spec \"%s\"; ignoring", sports
);
3767 strcpy(saddr
, sports
);
3770 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3774 if (*portfwd_strptr
== '\t')
3777 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3778 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3781 if (*portfwd_strptr
== ':')
3784 while (*portfwd_strptr
) {
3785 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3789 dport
= atoi(dports
);
3793 dport
= net_service_lookup(dports
);
3795 logeventf(ssh
, "Service lookup failed for destination"
3796 " port \"%s\"", dports
);
3800 while (*portfwd_strptr
) portfwd_strptr
++;
3802 portfwd_strptr
++; /* eat the NUL and move to next one */
3804 sport
= atoi(sports
);
3808 sport
= net_service_lookup(sports
);
3810 logeventf(ssh
, "Service lookup failed for source"
3811 " port \"%s\"", sports
);
3814 if (sport
&& dport
) {
3815 /* Set up a description of the source port. */
3816 struct ssh_portfwd
*pfrec
, *epfrec
;
3818 pfrec
= snew(struct ssh_portfwd
);
3820 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3821 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3822 pfrec
->sport
= sport
;
3823 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3824 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3825 pfrec
->dport
= dport
;
3826 pfrec
->local
= NULL
;
3827 pfrec
->remote
= NULL
;
3828 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3829 address_family
== '6' ? ADDRTYPE_IPV6
:
3832 epfrec
= add234(ssh
->portfwds
, pfrec
);
3833 if (epfrec
!= pfrec
) {
3835 * We already have a port forwarding with precisely
3836 * these parameters. Hence, no need to do anything;
3837 * simply tag the existing one as KEEP.
3839 epfrec
->status
= KEEP
;
3840 free_portfwd(pfrec
);
3842 pfrec
->status
= CREATE
;
3848 * Now go through and destroy any port forwardings which were
3851 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3852 if (epf
->status
== DESTROY
) {
3855 message
= dupprintf("%s port forwarding from %s%s%d",
3856 epf
->type
== 'L' ?
"local" :
3857 epf
->type
== 'R' ?
"remote" : "dynamic",
3858 epf
->saddr ? epf
->saddr
: "",
3859 epf
->saddr ?
":" : "",
3862 if (epf
->type
!= 'D') {
3863 char *msg2
= dupprintf("%s to %s:%d", message
,
3864 epf
->daddr
, epf
->dport
);
3869 logeventf(ssh
, "Cancelling %s", message
);
3873 struct ssh_rportfwd
*rpf
= epf
->remote
;
3874 struct Packet
*pktout
;
3877 * Cancel the port forwarding at the server
3880 if (ssh
->version
== 1) {
3882 * We cannot cancel listening ports on the
3883 * server side in SSH1! There's no message
3884 * to support it. Instead, we simply remove
3885 * the rportfwd record from the local end
3886 * so that any connections the server tries
3887 * to make on it are rejected.
3890 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3891 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3892 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3894 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3895 } else if (ssh
->cfg
.rport_acceptall
) {
3896 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3898 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3900 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3901 ssh2_pkt_send(ssh
, pktout
);
3904 del234(ssh
->rportfwds
, rpf
);
3906 } else if (epf
->local
) {
3907 pfd_terminate(epf
->local
);
3910 delpos234(ssh
->portfwds
, i
);
3912 i
--; /* so we don't skip one in the list */
3916 * And finally, set up any new port forwardings (status==CREATE).
3918 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3919 if (epf
->status
== CREATE
) {
3920 char *sportdesc
, *dportdesc
;
3921 sportdesc
= dupprintf("%s%s%s%s%d%s",
3922 epf
->saddr ? epf
->saddr
: "",
3923 epf
->saddr ?
":" : "",
3924 epf
->sserv ? epf
->sserv
: "",
3925 epf
->sserv ?
"(" : "",
3927 epf
->sserv ?
")" : "");
3928 if (epf
->type
== 'D') {
3931 dportdesc
= dupprintf("%s:%s%s%d%s",
3933 epf
->dserv ? epf
->dserv
: "",
3934 epf
->dserv ?
"(" : "",
3936 epf
->dserv ?
")" : "");
3939 if (epf
->type
== 'L') {
3940 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
3941 epf
->saddr
, epf
->sport
,
3944 epf
->addressfamily
);
3946 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
3947 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3948 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3949 sportdesc
, dportdesc
,
3950 err ?
" failed: " : "", err ? err
: "");
3951 } else if (epf
->type
== 'D') {
3952 const char *err
= pfd_addforward(NULL
, -1,
3953 epf
->saddr
, epf
->sport
,
3956 epf
->addressfamily
);
3958 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
3959 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3960 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3962 err ?
" failed: " : "", err ? err
: "");
3964 struct ssh_rportfwd
*pf
;
3967 * Ensure the remote port forwardings tree exists.
3969 if (!ssh
->rportfwds
) {
3970 if (ssh
->version
== 1)
3971 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3973 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3976 pf
= snew(struct ssh_rportfwd
);
3977 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
3978 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
3979 pf
->dport
= epf
->dport
;
3980 pf
->sport
= epf
->sport
;
3981 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3982 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
3983 epf
->daddr
, epf
->dport
);
3986 logeventf(ssh
, "Requesting remote port %s"
3987 " forward to %s", sportdesc
, dportdesc
);
3989 pf
->sportdesc
= sportdesc
;
3994 if (ssh
->version
== 1) {
3995 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3996 PKT_INT
, epf
->sport
,
3997 PKT_STR
, epf
->daddr
,
3998 PKT_INT
, epf
->dport
,
4000 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4002 ssh_rportfwd_succfail
, pf
);
4004 struct Packet
*pktout
;
4005 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4006 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4007 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4009 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4010 } else if (ssh
->cfg
.rport_acceptall
) {
4011 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4013 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4015 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4016 ssh2_pkt_send(ssh
, pktout
);
4018 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4019 SSH2_MSG_REQUEST_FAILURE
,
4020 ssh_rportfwd_succfail
, pf
);
4029 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4032 int stringlen
, bufsize
;
4034 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4035 if (string
== NULL
) {
4036 bombout(("Incoming terminal data packet was badly formed"));
4040 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4042 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4043 ssh
->v1_stdout_throttling
= 1;
4044 ssh1_throttle(ssh
, +1);
4048 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4050 /* Remote side is trying to open a channel to talk to our
4051 * X-Server. Give them back a local channel number. */
4052 struct ssh_channel
*c
;
4053 int remoteid
= ssh_pkt_getuint32(pktin
);
4055 logevent("Received X11 connect request");
4056 /* Refuse if X11 forwarding is disabled. */
4057 if (!ssh
->X11_fwd_enabled
) {
4058 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4059 PKT_INT
, remoteid
, PKT_END
);
4060 logevent("Rejected X11 connect request");
4062 c
= snew(struct ssh_channel
);
4065 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4066 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4067 logevent("Opening X11 forward connection failed");
4069 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4070 PKT_INT
, remoteid
, PKT_END
);
4073 ("Opening X11 forward connection succeeded");
4074 c
->remoteid
= remoteid
;
4075 c
->localid
= alloc_channel_id(ssh
);
4077 c
->v
.v1
.throttling
= 0;
4078 c
->type
= CHAN_X11
; /* identify channel type */
4079 add234(ssh
->channels
, c
);
4080 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4081 PKT_INT
, c
->remoteid
, PKT_INT
,
4082 c
->localid
, PKT_END
);
4083 logevent("Opened X11 forward channel");
4088 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4090 /* Remote side is trying to open a channel to talk to our
4091 * agent. Give them back a local channel number. */
4092 struct ssh_channel
*c
;
4093 int remoteid
= ssh_pkt_getuint32(pktin
);
4095 /* Refuse if agent forwarding is disabled. */
4096 if (!ssh
->agentfwd_enabled
) {
4097 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4098 PKT_INT
, remoteid
, PKT_END
);
4100 c
= snew(struct ssh_channel
);
4102 c
->remoteid
= remoteid
;
4103 c
->localid
= alloc_channel_id(ssh
);
4105 c
->v
.v1
.throttling
= 0;
4106 c
->type
= CHAN_AGENT
; /* identify channel type */
4107 c
->u
.a
.lensofar
= 0;
4108 add234(ssh
->channels
, c
);
4109 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4110 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4115 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4117 /* Remote side is trying to open a channel to talk to a
4118 * forwarded port. Give them back a local channel number. */
4119 struct ssh_channel
*c
;
4120 struct ssh_rportfwd pf
, *pfp
;
4123 char *host
, buf
[1024];
4125 c
= snew(struct ssh_channel
);
4128 remoteid
= ssh_pkt_getuint32(pktin
);
4129 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4130 port
= ssh_pkt_getuint32(pktin
);
4132 if (hostsize
>= lenof(pf
.dhost
))
4133 hostsize
= lenof(pf
.dhost
)-1;
4134 memcpy(pf
.dhost
, host
, hostsize
);
4135 pf
.dhost
[hostsize
] = '\0';
4137 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4140 sprintf(buf
, "Rejected remote port open request for %s:%d",
4143 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4144 PKT_INT
, remoteid
, PKT_END
);
4146 sprintf(buf
, "Received remote port open request for %s:%d",
4149 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4150 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4153 sprintf(buf
, "Port open failed: %s", e
);
4156 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4157 PKT_INT
, remoteid
, PKT_END
);
4159 c
->remoteid
= remoteid
;
4160 c
->localid
= alloc_channel_id(ssh
);
4162 c
->v
.v1
.throttling
= 0;
4163 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4164 add234(ssh
->channels
, c
);
4165 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4166 PKT_INT
, c
->remoteid
, PKT_INT
,
4167 c
->localid
, PKT_END
);
4168 logevent("Forwarded port opened successfully");
4173 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4175 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4176 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4177 struct ssh_channel
*c
;
4179 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4180 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4181 c
->remoteid
= localid
;
4182 c
->type
= CHAN_SOCKDATA
;
4183 c
->v
.v1
.throttling
= 0;
4184 pfd_confirm(c
->u
.pfd
.s
);
4187 if (c
&& c
->closes
) {
4189 * We have a pending close on this channel,
4190 * which we decided on before the server acked
4191 * the channel open. So now we know the
4192 * remoteid, we can close it again.
4194 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4195 PKT_INT
, c
->remoteid
, PKT_END
);
4199 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4201 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4202 struct ssh_channel
*c
;
4204 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4205 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4206 logevent("Forwarded connection refused by server");
4207 pfd_close(c
->u
.pfd
.s
);
4208 del234(ssh
->channels
, c
);
4213 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4215 /* Remote side closes a channel. */
4216 unsigned i
= ssh_pkt_getuint32(pktin
);
4217 struct ssh_channel
*c
;
4218 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4219 if (c
&& ((int)c
->remoteid
) != -1) {
4222 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4224 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4225 logevent("Forwarded X11 connection terminated");
4226 assert(c
->u
.x11
.s
!= NULL
);
4227 x11_close(c
->u
.x11
.s
);
4230 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4231 logevent("Forwarded port closed");
4232 assert(c
->u
.pfd
.s
!= NULL
);
4233 pfd_close(c
->u
.pfd
.s
);
4237 c
->closes
|= (closetype
<< 2); /* seen this message */
4238 if (!(c
->closes
& closetype
)) {
4239 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4241 c
->closes
|= closetype
; /* sent it too */
4244 if (c
->closes
== 15) {
4245 del234(ssh
->channels
, c
);
4249 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4250 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4251 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4256 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4258 /* Data sent down one of our channels. */
4259 int i
= ssh_pkt_getuint32(pktin
);
4262 struct ssh_channel
*c
;
4264 ssh_pkt_getstring(pktin
, &p
, &len
);
4266 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4271 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4274 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4277 /* Data for an agent message. Buffer it. */
4279 if (c
->u
.a
.lensofar
< 4) {
4280 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4281 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4285 c
->u
.a
.lensofar
+= l
;
4287 if (c
->u
.a
.lensofar
== 4) {
4289 4 + GET_32BIT(c
->u
.a
.msglen
);
4290 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4292 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4294 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4296 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4298 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4302 c
->u
.a
.lensofar
+= l
;
4304 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4307 if (agent_query(c
->u
.a
.message
,
4310 ssh_agentf_callback
, c
))
4311 ssh_agentf_callback(c
, reply
, replylen
);
4312 sfree(c
->u
.a
.message
);
4313 c
->u
.a
.lensofar
= 0;
4316 bufsize
= 0; /* agent channels never back up */
4319 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4320 c
->v
.v1
.throttling
= 1;
4321 ssh1_throttle(ssh
, +1);
4326 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4329 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4330 sprintf(buf
, "Server sent command exit status %d",
4333 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4335 * In case `helpful' firewalls or proxies tack
4336 * extra human-readable text on the end of the
4337 * session which we might mistake for another
4338 * encrypted packet, we close the session once
4339 * we've sent EXIT_CONFIRMATION.
4341 ssh
->close_expected
= TRUE
;
4342 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4345 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4346 struct Packet
*pktin
)
4348 crBegin(ssh
->do_ssh1_connection_crstate
);
4350 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4351 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4352 ssh1_smsg_stdout_stderr_data
;
4354 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4355 ssh1_msg_channel_open_confirmation
;
4356 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4357 ssh1_msg_channel_open_failure
;
4358 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4359 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4360 ssh1_msg_channel_close
;
4361 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4362 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4364 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4365 logevent("Requesting agent forwarding");
4366 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4370 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4371 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4372 bombout(("Protocol confusion"));
4374 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4375 logevent("Agent forwarding refused");
4377 logevent("Agent forwarding enabled");
4378 ssh
->agentfwd_enabled
= TRUE
;
4379 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4383 if (ssh
->cfg
.x11_forward
) {
4384 char proto
[20], data
[64];
4385 logevent("Requesting X11 forwarding");
4386 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4387 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4388 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4389 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4390 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4391 PKT_STR
, proto
, PKT_STR
, data
,
4392 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4395 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4396 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4401 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4402 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4403 bombout(("Protocol confusion"));
4405 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4406 logevent("X11 forwarding refused");
4408 logevent("X11 forwarding enabled");
4409 ssh
->X11_fwd_enabled
= TRUE
;
4410 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4414 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4415 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4417 if (!ssh
->cfg
.nopty
) {
4418 /* Unpick the terminal-speed string. */
4419 /* XXX perhaps we should allow no speeds to be sent. */
4420 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4421 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4422 /* Send the pty request. */
4423 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4424 PKT_STR
, ssh
->cfg
.termtype
,
4425 PKT_INT
, ssh
->term_height
,
4426 PKT_INT
, ssh
->term_width
,
4427 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4428 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4429 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4430 PKT_CHAR
, 0, PKT_END
);
4431 ssh
->state
= SSH_STATE_INTERMED
;
4435 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4436 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4437 bombout(("Protocol confusion"));
4439 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4440 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4441 ssh
->editing
= ssh
->echoing
= 1;
4443 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4444 ssh
->ospeed
, ssh
->ispeed
);
4446 ssh
->editing
= ssh
->echoing
= 1;
4449 if (ssh
->cfg
.compression
) {
4450 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4454 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4455 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4456 bombout(("Protocol confusion"));
4458 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4459 c_write_str(ssh
, "Server refused to compress\r\n");
4461 logevent("Started compression");
4462 ssh
->v1_compressing
= TRUE
;
4463 ssh
->cs_comp_ctx
= zlib_compress_init();
4464 logevent("Initialised zlib (RFC1950) compression");
4465 ssh
->sc_comp_ctx
= zlib_decompress_init();
4466 logevent("Initialised zlib (RFC1950) decompression");
4470 * Start the shell or command.
4472 * Special case: if the first-choice command is an SSH2
4473 * subsystem (hence not usable here) and the second choice
4474 * exists, we fall straight back to that.
4477 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4479 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4480 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4481 ssh
->fallback_cmd
= TRUE
;
4484 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4486 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4487 logevent("Started session");
4490 ssh
->state
= SSH_STATE_SESSION
;
4491 if (ssh
->size_needed
)
4492 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4493 if (ssh
->eof_needed
)
4494 ssh_special(ssh
, TS_EOF
);
4497 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4499 ssh
->channels
= newtree234(ssh_channelcmp
);
4503 * By this point, most incoming packets are already being
4504 * handled by the dispatch table, and we need only pay
4505 * attention to the unusual ones.
4510 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4511 /* may be from EXEC_SHELL on some servers */
4512 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4513 /* may be from EXEC_SHELL on some servers
4514 * if no pty is available or in other odd cases. Ignore */
4516 bombout(("Strange packet received: type %d", pktin
->type
));
4521 int len
= min(inlen
, 512);
4522 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4523 PKT_INT
, len
, PKT_DATA
, in
, len
,
4524 PKTT_OTHER
, PKT_END
);
4535 * Handle the top-level SSH2 protocol.
4537 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4542 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4543 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4548 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4550 /* log reason code in disconnect message */
4554 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4555 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4558 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4560 /* Do nothing, because we're ignoring it! Duhh. */
4563 static void ssh1_protocol_setup(Ssh ssh
)
4568 * Most messages are handled by the coroutines.
4570 for (i
= 0; i
< 256; i
++)
4571 ssh
->packet_dispatch
[i
] = NULL
;
4574 * These special message types we install handlers for.
4576 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4577 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4578 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4581 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4582 struct Packet
*pktin
)
4584 if (ssh
->state
== SSH_STATE_CLOSED
)
4587 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4588 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4592 if (!ssh
->protocol_initial_phase_done
) {
4593 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4594 ssh
->protocol_initial_phase_done
= TRUE
;
4599 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4603 * Utility routine for decoding comma-separated strings in KEXINIT.
4605 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4608 if (!needle
|| !haystack
) /* protect against null pointers */
4610 needlen
= strlen(needle
);
4613 * Is it at the start of the string?
4615 if (haylen
>= needlen
&& /* haystack is long enough */
4616 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4617 (haylen
== needlen
|| haystack
[needlen
] == ',')
4618 /* either , or EOS follows */
4622 * If not, search for the next comma and resume after that.
4623 * If no comma found, terminate.
4625 while (haylen
> 0 && *haystack
!= ',')
4626 haylen
--, haystack
++;
4629 haylen
--, haystack
++; /* skip over comma itself */
4634 * SSH2 key creation method.
4636 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4637 unsigned char *sessid
, char chr
,
4638 unsigned char *keyspace
)
4641 /* First 20 bytes. */
4643 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4645 SHA_Bytes(&s
, H
, 20);
4646 SHA_Bytes(&s
, &chr
, 1);
4647 SHA_Bytes(&s
, sessid
, 20);
4648 SHA_Final(&s
, keyspace
);
4649 /* Next 20 bytes. */
4651 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4653 SHA_Bytes(&s
, H
, 20);
4654 SHA_Bytes(&s
, keyspace
, 20);
4655 SHA_Final(&s
, keyspace
+ 20);
4659 * Handle the SSH2 transport layer.
4661 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4662 struct Packet
*pktin
)
4664 struct do_ssh2_transport_state
{
4665 int nbits
, pbits
, warn
;
4666 Bignum p
, g
, e
, f
, K
;
4667 int kex_init_value
, kex_reply_value
;
4668 const struct ssh_mac
**maclist
;
4670 const struct ssh2_cipher
*cscipher_tobe
;
4671 const struct ssh2_cipher
*sccipher_tobe
;
4672 const struct ssh_mac
*csmac_tobe
;
4673 const struct ssh_mac
*scmac_tobe
;
4674 const struct ssh_compress
*cscomp_tobe
;
4675 const struct ssh_compress
*sccomp_tobe
;
4676 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4677 int hostkeylen
, siglen
;
4678 void *hkey
; /* actual host key */
4679 unsigned char exchange_hash
[20];
4680 int n_preferred_kex
;
4681 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4682 int n_preferred_ciphers
;
4683 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4684 const struct ssh_compress
*preferred_comp
;
4685 int got_session_id
, activated_authconn
;
4686 struct Packet
*pktout
;
4688 crState(do_ssh2_transport_state
);
4690 crBegin(ssh
->do_ssh2_transport_crstate
);
4692 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4693 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4694 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4696 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4699 * Be prepared to work around the buggy MAC problem.
4701 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4702 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4704 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4707 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4709 int i
, j
, commalist_started
;
4712 * Set up the preferred key exchange. (NULL => warn below here)
4714 s
->n_preferred_kex
= 0;
4715 for (i
= 0; i
< KEX_MAX
; i
++) {
4716 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4718 s
->preferred_kex
[s
->n_preferred_kex
++] =
4719 &ssh_diffiehellman_gex
;
4722 s
->preferred_kex
[s
->n_preferred_kex
++] =
4723 &ssh_diffiehellman_group14
;
4726 s
->preferred_kex
[s
->n_preferred_kex
++] =
4727 &ssh_diffiehellman_group1
;
4730 /* Flag for later. Don't bother if it's the last in
4732 if (i
< KEX_MAX
- 1) {
4733 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4740 * Set up the preferred ciphers. (NULL => warn below here)
4742 s
->n_preferred_ciphers
= 0;
4743 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4744 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4745 case CIPHER_BLOWFISH
:
4746 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4749 if (ssh
->cfg
.ssh2_des_cbc
) {
4750 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4754 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4757 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4760 /* Flag for later. Don't bother if it's the last in
4762 if (i
< CIPHER_MAX
- 1) {
4763 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4770 * Set up preferred compression.
4772 if (ssh
->cfg
.compression
)
4773 s
->preferred_comp
= &ssh_zlib
;
4775 s
->preferred_comp
= &ssh_comp_none
;
4778 * Enable queueing of outgoing auth- or connection-layer
4779 * packets while we are in the middle of a key exchange.
4781 ssh
->queueing
= TRUE
;
4784 * Flag that KEX is in progress.
4786 ssh
->kex_in_progress
= TRUE
;
4789 * Construct and send our key exchange packet.
4791 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4792 for (i
= 0; i
< 16; i
++)
4793 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4794 /* List key exchange algorithms. */
4795 ssh2_pkt_addstring_start(s
->pktout
);
4796 commalist_started
= 0;
4797 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4798 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4799 if (!k
) continue; /* warning flag */
4800 if (commalist_started
)
4801 ssh2_pkt_addstring_str(s
->pktout
, ",");
4802 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4803 commalist_started
= 1;
4805 /* List server host key algorithms. */
4806 ssh2_pkt_addstring_start(s
->pktout
);
4807 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4808 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4809 if (i
< lenof(hostkey_algs
) - 1)
4810 ssh2_pkt_addstring_str(s
->pktout
, ",");
4812 /* List client->server encryption algorithms. */
4813 ssh2_pkt_addstring_start(s
->pktout
);
4814 commalist_started
= 0;
4815 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4816 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4817 if (!c
) continue; /* warning flag */
4818 for (j
= 0; j
< c
->nciphers
; j
++) {
4819 if (commalist_started
)
4820 ssh2_pkt_addstring_str(s
->pktout
, ",");
4821 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4822 commalist_started
= 1;
4825 /* List server->client encryption algorithms. */
4826 ssh2_pkt_addstring_start(s
->pktout
);
4827 commalist_started
= 0;
4828 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4829 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4830 if (!c
) continue; /* warning flag */
4831 for (j
= 0; j
< c
->nciphers
; j
++) {
4832 if (commalist_started
)
4833 ssh2_pkt_addstring_str(s
->pktout
, ",");
4834 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4835 commalist_started
= 1;
4838 /* List client->server MAC algorithms. */
4839 ssh2_pkt_addstring_start(s
->pktout
);
4840 for (i
= 0; i
< s
->nmacs
; i
++) {
4841 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4842 if (i
< s
->nmacs
- 1)
4843 ssh2_pkt_addstring_str(s
->pktout
, ",");
4845 /* List server->client MAC algorithms. */
4846 ssh2_pkt_addstring_start(s
->pktout
);
4847 for (i
= 0; i
< s
->nmacs
; i
++) {
4848 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4849 if (i
< s
->nmacs
- 1)
4850 ssh2_pkt_addstring_str(s
->pktout
, ",");
4852 /* List client->server compression algorithms. */
4853 ssh2_pkt_addstring_start(s
->pktout
);
4854 assert(lenof(compressions
) > 1);
4855 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4856 for (i
= 0; i
< lenof(compressions
); i
++) {
4857 const struct ssh_compress
*c
= compressions
[i
];
4858 if (c
!= s
->preferred_comp
) {
4859 ssh2_pkt_addstring_str(s
->pktout
, ",");
4860 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4863 /* List server->client compression algorithms. */
4864 ssh2_pkt_addstring_start(s
->pktout
);
4865 assert(lenof(compressions
) > 1);
4866 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4867 for (i
= 0; i
< lenof(compressions
); i
++) {
4868 const struct ssh_compress
*c
= compressions
[i
];
4869 if (c
!= s
->preferred_comp
) {
4870 ssh2_pkt_addstring_str(s
->pktout
, ",");
4871 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4874 /* List client->server languages. Empty list. */
4875 ssh2_pkt_addstring_start(s
->pktout
);
4876 /* List server->client languages. Empty list. */
4877 ssh2_pkt_addstring_start(s
->pktout
);
4878 /* First KEX packet does _not_ follow, because we're not that brave. */
4879 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4881 ssh2_pkt_adduint32(s
->pktout
, 0);
4884 ssh
->exhash
= ssh
->exhashbase
;
4885 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4887 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4891 if (pktin
->length
> 5)
4892 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4895 * Now examine the other side's KEXINIT to see what we're up
4902 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4903 bombout(("expected key exchange packet from server"));
4907 ssh
->hostkey
= NULL
;
4908 s
->cscipher_tobe
= NULL
;
4909 s
->sccipher_tobe
= NULL
;
4910 s
->csmac_tobe
= NULL
;
4911 s
->scmac_tobe
= NULL
;
4912 s
->cscomp_tobe
= NULL
;
4913 s
->sccomp_tobe
= NULL
;
4914 pktin
->savedpos
+= 16; /* skip garbage cookie */
4915 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4917 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4918 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4921 } else if (in_commasep_string(k
->name
, str
, len
)) {
4926 sk_set_frozen(ssh
->s
, 1);
4927 askalg(ssh
->frontend
, "key-exchange algorithm",
4929 sk_set_frozen(ssh
->s
, 0);
4935 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4936 str ? str
: "(null)"));
4939 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4940 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4941 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4942 ssh
->hostkey
= hostkey_algs
[i
];
4946 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4948 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4949 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4953 for (j
= 0; j
< c
->nciphers
; j
++) {
4954 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4955 s
->cscipher_tobe
= c
->list
[j
];
4960 if (s
->cscipher_tobe
) {
4962 sk_set_frozen(ssh
->s
, 1);
4963 askalg(ssh
->frontend
, "client-to-server cipher",
4964 s
->cscipher_tobe
->name
);
4965 sk_set_frozen(ssh
->s
, 0);
4970 if (!s
->cscipher_tobe
) {
4971 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4972 str ? str
: "(null)"));
4976 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4978 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4979 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4983 for (j
= 0; j
< c
->nciphers
; j
++) {
4984 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4985 s
->sccipher_tobe
= c
->list
[j
];
4990 if (s
->sccipher_tobe
) {
4992 sk_set_frozen(ssh
->s
, 1);
4993 askalg(ssh
->frontend
, "server-to-client cipher",
4994 s
->sccipher_tobe
->name
);
4995 sk_set_frozen(ssh
->s
, 0);
5000 if (!s
->sccipher_tobe
) {
5001 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5002 str ? str
: "(null)"));
5006 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5007 for (i
= 0; i
< s
->nmacs
; i
++) {
5008 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5009 s
->csmac_tobe
= s
->maclist
[i
];
5013 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5014 for (i
= 0; i
< s
->nmacs
; i
++) {
5015 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5016 s
->scmac_tobe
= s
->maclist
[i
];
5020 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5021 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5022 const struct ssh_compress
*c
=
5023 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5024 if (in_commasep_string(c
->name
, str
, len
)) {
5029 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5030 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5031 const struct ssh_compress
*c
=
5032 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5033 if (in_commasep_string(c
->name
, str
, len
)) {
5041 * Work out the number of bits of key we will need from the key
5042 * exchange. We start with the maximum key length of either
5048 csbits
= s
->cscipher_tobe
->keylen
;
5049 scbits
= s
->sccipher_tobe
->keylen
;
5050 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5052 /* The keys only have 160-bit entropy, since they're based on
5053 * a SHA-1 hash. So cap the key size at 160 bits. */
5058 * If we're doing Diffie-Hellman group exchange, start by
5059 * requesting a group.
5061 if (!ssh
->kex
->pdata
) {
5062 logevent("Doing Diffie-Hellman group exchange");
5063 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5065 * Work out how big a DH group we will need to allow that
5068 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5069 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5070 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5071 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5074 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5075 bombout(("expected key exchange group packet from server"));
5078 s
->p
= ssh2_pkt_getmp(pktin
);
5079 s
->g
= ssh2_pkt_getmp(pktin
);
5080 if (!s
->p
|| !s
->g
) {
5081 bombout(("unable to read mp-ints from incoming group packet"));
5084 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5085 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5086 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5088 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5089 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5090 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5091 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5092 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5093 ssh
->kex
->groupname
);
5096 logevent("Doing Diffie-Hellman key exchange");
5098 * Now generate and send e for Diffie-Hellman.
5100 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5101 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5102 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5103 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5106 if (pktin
->type
!= s
->kex_reply_value
) {
5107 bombout(("expected key exchange reply packet from server"));
5110 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5111 s
->f
= ssh2_pkt_getmp(pktin
);
5113 bombout(("unable to parse key exchange reply packet"));
5116 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5118 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5120 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5121 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5122 sha_uint32(&ssh
->exhash
, s
->pbits
);
5123 sha_mpint(&ssh
->exhash
, s
->p
);
5124 sha_mpint(&ssh
->exhash
, s
->g
);
5126 sha_mpint(&ssh
->exhash
, s
->e
);
5127 sha_mpint(&ssh
->exhash
, s
->f
);
5128 sha_mpint(&ssh
->exhash
, s
->K
);
5129 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5131 dh_cleanup(ssh
->kex_ctx
);
5132 ssh
->kex_ctx
= NULL
;
5135 debug(("Exchange hash is:\n"));
5136 dmemdump(s
->exchange_hash
, 20);
5139 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5141 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5142 (char *)s
->exchange_hash
, 20)) {
5143 bombout(("Server's host key did not match the signature supplied"));
5148 * Authenticate remote host: verify host key. (We've already
5149 * checked the signature of the exchange hash.)
5151 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5152 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5153 sk_set_frozen(ssh
->s
, 1);
5154 verify_ssh_host_key(ssh
->frontend
,
5155 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5156 s
->keystr
, s
->fingerprint
);
5157 sk_set_frozen(ssh
->s
, 0);
5158 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5159 logevent("Host key fingerprint is:");
5160 logevent(s
->fingerprint
);
5162 sfree(s
->fingerprint
);
5164 ssh
->hostkey
->freekey(s
->hkey
);
5167 * The exchange hash from the very first key exchange is also
5168 * the session id, used in session key construction and
5171 if (!s
->got_session_id
) {
5172 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5173 sizeof(s
->exchange_hash
));
5174 s
->got_session_id
= TRUE
;
5178 * Send SSH2_MSG_NEWKEYS.
5180 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5181 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5182 ssh
->outgoing_data_size
= 0; /* start counting from here */
5185 * We've sent client NEWKEYS, so create and initialise
5186 * client-to-server session keys.
5188 if (ssh
->cs_cipher_ctx
)
5189 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5190 ssh
->cscipher
= s
->cscipher_tobe
;
5191 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5193 if (ssh
->cs_mac_ctx
)
5194 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5195 ssh
->csmac
= s
->csmac_tobe
;
5196 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5198 if (ssh
->cs_comp_ctx
)
5199 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5200 ssh
->cscomp
= s
->cscomp_tobe
;
5201 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5204 * Set IVs on client-to-server keys. Here we use the exchange
5205 * hash from the _first_ key exchange.
5208 unsigned char keyspace
[40];
5209 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5210 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5211 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5212 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5213 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5214 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5217 logeventf(ssh
, "Initialised %.200s client->server encryption",
5218 ssh
->cscipher
->text_name
);
5219 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5220 ssh
->csmac
->text_name
);
5221 if (ssh
->cscomp
->text_name
)
5222 logeventf(ssh
, "Initialised %s compression",
5223 ssh
->cscomp
->text_name
);
5226 * Now our end of the key exchange is complete, we can send all
5227 * our queued higher-layer packets.
5229 ssh
->queueing
= FALSE
;
5230 ssh2_pkt_queuesend(ssh
);
5233 * Expect SSH2_MSG_NEWKEYS from server.
5236 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5237 bombout(("expected new-keys packet from server"));
5240 ssh
->incoming_data_size
= 0; /* start counting from here */
5243 * We've seen server NEWKEYS, so create and initialise
5244 * server-to-client session keys.
5246 if (ssh
->sc_cipher_ctx
)
5247 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5248 ssh
->sccipher
= s
->sccipher_tobe
;
5249 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5251 if (ssh
->sc_mac_ctx
)
5252 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5253 ssh
->scmac
= s
->scmac_tobe
;
5254 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5256 if (ssh
->sc_comp_ctx
)
5257 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5258 ssh
->sccomp
= s
->sccomp_tobe
;
5259 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5262 * Set IVs on server-to-client keys. Here we use the exchange
5263 * hash from the _first_ key exchange.
5266 unsigned char keyspace
[40];
5267 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5268 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5269 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5270 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5271 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5272 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5274 logeventf(ssh
, "Initialised %.200s server->client encryption",
5275 ssh
->sccipher
->text_name
);
5276 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5277 ssh
->scmac
->text_name
);
5278 if (ssh
->sccomp
->text_name
)
5279 logeventf(ssh
, "Initialised %s decompression",
5280 ssh
->sccomp
->text_name
);
5283 * Free key exchange data.
5287 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5293 * Key exchange is over. Loop straight back round if we have a
5294 * deferred rekey reason.
5296 if (ssh
->deferred_rekey_reason
) {
5297 logevent(ssh
->deferred_rekey_reason
);
5299 ssh
->deferred_rekey_reason
= NULL
;
5300 goto begin_key_exchange
;
5304 * Otherwise, schedule a timer for our next rekey.
5306 ssh
->kex_in_progress
= FALSE
;
5307 ssh
->last_rekey
= GETTICKCOUNT();
5308 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5309 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5313 * If this is the first key exchange phase, we must pass the
5314 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5315 * wants to see it but because it will need time to initialise
5316 * itself before it sees an actual packet. In subsequent key
5317 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5318 * it would only confuse the layer above.
5320 if (s
->activated_authconn
) {
5323 s
->activated_authconn
= TRUE
;
5326 * Now we're encrypting. Begin returning 1 to the protocol main
5327 * function so that other things can run on top of the
5328 * transport. If we ever see a KEXINIT, we must go back to the
5331 * We _also_ go back to the start if we see pktin==NULL and
5332 * inlen==-1, because this is a special signal meaning
5333 * `initiate client-driven rekey', and `in' contains a message
5334 * giving the reason for the rekey.
5336 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5337 (!pktin
&& inlen
== -1))) {
5342 logevent("Server initiated key re-exchange");
5345 * Special case: if the server bug is set that doesn't
5346 * allow rekeying, we give a different log message and
5347 * continue waiting. (If such a server _initiates_ a rekey,
5348 * we process it anyway!)
5350 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5351 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5353 /* Reset the counters, so that at least this message doesn't
5354 * hit the event log _too_ often. */
5355 ssh
->outgoing_data_size
= 0;
5356 ssh
->incoming_data_size
= 0;
5357 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5359 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5362 goto wait_for_rekey
; /* this is utterly horrid */
5364 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5367 goto begin_key_exchange
;
5373 * Add data to an SSH2 channel output buffer.
5375 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5378 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5382 * Attempt to send data on an SSH2 channel.
5384 static int ssh2_try_send(struct ssh_channel
*c
)
5387 struct Packet
*pktout
;
5389 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5392 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5393 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5394 len
= c
->v
.v2
.remwindow
;
5395 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5396 len
= c
->v
.v2
.remmaxpkt
;
5397 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5398 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5399 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5400 ssh2_pkt_addstring_start(pktout
);
5401 ssh2_pkt_addstring_data(pktout
, data
, len
);
5402 end_log_omission(ssh
, pktout
);
5403 ssh2_pkt_send(ssh
, pktout
);
5404 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5405 c
->v
.v2
.remwindow
-= len
;
5409 * After having sent as much data as we can, return the amount
5412 return bufchain_size(&c
->v
.v2
.outbuffer
);
5416 * Potentially enlarge the window on an SSH2 channel.
5418 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5423 * Never send WINDOW_ADJUST for a channel that the remote side
5424 * already thinks it's closed; there's no point, since it won't
5425 * be sending any more data anyway.
5430 if (newwin
> c
->v
.v2
.locwindow
) {
5431 struct Packet
*pktout
;
5433 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5434 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5435 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5436 ssh2_pkt_send(ssh
, pktout
);
5437 c
->v
.v2
.locwindow
= newwin
;
5441 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5443 unsigned i
= ssh_pkt_getuint32(pktin
);
5444 struct ssh_channel
*c
;
5445 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5446 if (c
&& !c
->closes
)
5447 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5450 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5453 unsigned int length
;
5454 unsigned i
= ssh_pkt_getuint32(pktin
);
5455 struct ssh_channel
*c
;
5456 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5458 return; /* nonexistent channel */
5459 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5460 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5461 return; /* extended but not stderr */
5462 ssh_pkt_getstring(pktin
, &data
, &length
);
5465 c
->v
.v2
.locwindow
-= length
;
5467 case CHAN_MAINSESSION
:
5469 from_backend(ssh
->frontend
, pktin
->type
==
5470 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5474 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5477 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5480 while (length
> 0) {
5481 if (c
->u
.a
.lensofar
< 4) {
5482 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5483 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5487 c
->u
.a
.lensofar
+= l
;
5489 if (c
->u
.a
.lensofar
== 4) {
5491 4 + GET_32BIT(c
->u
.a
.msglen
);
5492 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5494 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5496 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5498 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5500 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5504 c
->u
.a
.lensofar
+= l
;
5506 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5509 if (agent_query(c
->u
.a
.message
,
5512 ssh_agentf_callback
, c
))
5513 ssh_agentf_callback(c
, reply
, replylen
);
5514 sfree(c
->u
.a
.message
);
5515 c
->u
.a
.lensofar
= 0;
5522 * If we are not buffering too much data,
5523 * enlarge the window again at the remote side.
5525 if (bufsize
< OUR_V2_WINSIZE
)
5526 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5530 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5532 unsigned i
= ssh_pkt_getuint32(pktin
);
5533 struct ssh_channel
*c
;
5535 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5537 return; /* nonexistent channel */
5539 if (c
->type
== CHAN_X11
) {
5541 * Remote EOF on an X11 channel means we should
5542 * wrap up and close the channel ourselves.
5544 x11_close(c
->u
.x11
.s
);
5546 } else if (c
->type
== CHAN_AGENT
) {
5548 } else if (c
->type
== CHAN_SOCKDATA
) {
5549 pfd_close(c
->u
.pfd
.s
);
5554 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5556 unsigned i
= ssh_pkt_getuint32(pktin
);
5557 struct ssh_channel
*c
;
5558 struct Packet
*pktout
;
5560 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5561 if (!c
|| ((int)c
->remoteid
) == -1) {
5562 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5563 c ?
"half-open" : "nonexistent", i
));
5566 /* Do pre-close processing on the channel. */
5568 case CHAN_MAINSESSION
:
5569 ssh
->mainchan
= NULL
;
5570 update_specials_menu(ssh
->frontend
);
5573 if (c
->u
.x11
.s
!= NULL
)
5574 x11_close(c
->u
.x11
.s
);
5581 if (c
->u
.pfd
.s
!= NULL
)
5582 pfd_close(c
->u
.pfd
.s
);
5586 if (c
->closes
== 0) {
5587 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5588 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5589 ssh2_pkt_send(ssh
, pktout
);
5591 del234(ssh
->channels
, c
);
5592 bufchain_clear(&c
->v
.v2
.outbuffer
);
5596 * See if that was the last channel left open.
5597 * (This is only our termination condition if we're
5598 * not running in -N mode.)
5600 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5601 logevent("All channels closed. Disconnecting");
5604 * We used to send SSH_MSG_DISCONNECT here,
5605 * because I'd believed that _every_ conforming
5606 * SSH2 connection had to end with a disconnect
5607 * being sent by at least one side; apparently
5608 * I was wrong and it's perfectly OK to
5609 * unceremoniously slam the connection shut
5610 * when you're done, and indeed OpenSSH feels
5611 * this is more polite than sending a
5612 * DISCONNECT. So now we don't.
5614 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5615 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5616 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5617 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5618 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5620 ssh
->close_expected
= TRUE
;
5621 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5625 static void ssh2_msg_channel_open_confirmation(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
);
5633 return; /* nonexistent channel */
5634 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5635 return; /* dunno why they're confirming this */
5636 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5637 c
->type
= CHAN_SOCKDATA
;
5638 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5639 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5641 pfd_confirm(c
->u
.pfd
.s
);
5644 * We have a pending close on this channel,
5645 * which we decided on before the server acked
5646 * the channel open. So now we know the
5647 * remoteid, we can close it again.
5649 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5650 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5651 ssh2_pkt_send(ssh
, pktout
);
5655 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5657 static const char *const reasons
[] = {
5658 "<unknown reason code>",
5659 "Administratively prohibited",
5661 "Unknown channel type",
5662 "Resource shortage",
5664 unsigned i
= ssh_pkt_getuint32(pktin
);
5665 unsigned reason_code
;
5666 char *reason_string
;
5669 struct ssh_channel
*c
;
5670 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5672 return; /* nonexistent channel */
5673 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5674 return; /* dunno why they're failing this */
5676 reason_code
= ssh_pkt_getuint32(pktin
);
5677 if (reason_code
>= lenof(reasons
))
5678 reason_code
= 0; /* ensure reasons[reason_code] in range */
5679 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5680 message
= dupprintf("Forwarded connection refused by"
5681 " server: %s [%.*s]", reasons
[reason_code
],
5682 reason_length
, reason_string
);
5686 pfd_close(c
->u
.pfd
.s
);
5688 del234(ssh
->channels
, c
);
5692 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5696 int typelen
, want_reply
;
5697 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5698 struct ssh_channel
*c
;
5699 struct Packet
*pktout
;
5701 localid
= ssh_pkt_getuint32(pktin
);
5702 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5703 want_reply
= ssh2_pkt_getbool(pktin
);
5706 * First, check that the channel exists. Otherwise,
5707 * we can instantly disconnect with a rude message.
5709 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5712 sprintf(buf
, "Received channel request for nonexistent"
5713 " channel %d", localid
);
5715 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5716 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5717 ssh2_pkt_addstring(pktout
, buf
);
5718 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5719 ssh2_pkt_send_noqueue(ssh
, pktout
);
5720 connection_fatal(ssh
->frontend
, "%s", buf
);
5721 ssh
->close_expected
= TRUE
;
5722 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5727 * Having got the channel number, we now look at
5728 * the request type string to see if it's something
5731 if (c
== ssh
->mainchan
) {
5733 * We recognise "exit-status" and "exit-signal" on
5734 * the primary channel.
5736 if (typelen
== 11 &&
5737 !memcmp(type
, "exit-status", 11)) {
5739 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5740 logeventf(ssh
, "Server sent command exit status %d",
5742 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5744 } else if (typelen
== 11 &&
5745 !memcmp(type
, "exit-signal", 11)) {
5747 int is_plausible
= TRUE
, is_int
= FALSE
;
5748 char *fmt_sig
= "", *fmt_msg
= "";
5750 int msglen
= 0, core
= FALSE
;
5751 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5752 * provide an `int' for the signal, despite its
5753 * having been a `string' in the drafts since at
5754 * least 2001. (Fixed in session.c 1.147.) Try to
5755 * infer which we can safely parse it as. */
5757 unsigned char *p
= pktin
->body
+
5759 long len
= pktin
->length
- pktin
->savedpos
;
5760 unsigned long num
= GET_32BIT(p
); /* what is it? */
5761 /* If it's 0, it hardly matters; assume string */
5765 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5766 #define CHECK_HYPOTHESIS(offset, result) \
5769 if (q >= 0 && q+4 <= len) { \
5770 q = q + 4 + GET_32BIT(p+q); \
5771 if (q >= 0 && q+4 <= len && \
5772 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5776 CHECK_HYPOTHESIS(4+1, maybe_int
);
5777 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5778 #undef CHECK_HYPOTHESIS
5779 if (maybe_int
&& !maybe_str
)
5781 else if (!maybe_int
&& maybe_str
)
5784 /* Crikey. Either or neither. Panic. */
5785 is_plausible
= FALSE
;
5790 /* Old non-standard OpenSSH. */
5791 int signum
= ssh_pkt_getuint32(pktin
);
5792 fmt_sig
= dupprintf(" %d", signum
);
5794 /* As per the drafts. */
5797 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5798 /* Signal name isn't supposed to be blank, but
5799 * let's cope gracefully if it is. */
5801 fmt_sig
= dupprintf(" \"%.*s\"",
5805 core
= ssh2_pkt_getbool(pktin
);
5806 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5808 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5810 /* ignore lang tag */
5811 } /* else don't attempt to parse */
5812 logeventf(ssh
, "Server exited on signal%s%s%s",
5813 fmt_sig
, core ?
" (core dumped)" : "",
5815 if (*fmt_sig
) sfree(fmt_sig
);
5816 if (*fmt_msg
) sfree(fmt_msg
);
5817 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5822 * This is a channel request we don't know
5823 * about, so we now either ignore the request
5824 * or respond with CHANNEL_FAILURE, depending
5827 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5830 pktout
= ssh2_pkt_init(reply
);
5831 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5832 ssh2_pkt_send(ssh
, pktout
);
5836 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5839 int typelen
, want_reply
;
5840 struct Packet
*pktout
;
5842 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5843 want_reply
= ssh2_pkt_getbool(pktin
);
5846 * We currently don't support any global requests
5847 * at all, so we either ignore the request or
5848 * respond with REQUEST_FAILURE, depending on
5852 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5853 ssh2_pkt_send(ssh
, pktout
);
5857 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5865 struct ssh_channel
*c
;
5866 unsigned remid
, winsize
, pktsize
;
5867 struct Packet
*pktout
;
5869 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5870 c
= snew(struct ssh_channel
);
5873 remid
= ssh_pkt_getuint32(pktin
);
5874 winsize
= ssh_pkt_getuint32(pktin
);
5875 pktsize
= ssh_pkt_getuint32(pktin
);
5877 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5880 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5881 addrstr
= snewn(peeraddrlen
+1, char);
5882 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5883 addrstr
[peeraddrlen
] = '\0';
5884 peerport
= ssh_pkt_getuint32(pktin
);
5886 logeventf(ssh
, "Received X11 connect request from %s:%d",
5889 if (!ssh
->X11_fwd_enabled
)
5890 error
= "X11 forwarding is not enabled";
5891 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5892 ssh
->x11auth
, addrstr
, peerport
,
5893 &ssh
->cfg
) != NULL
) {
5894 error
= "Unable to open an X11 connection";
5896 logevent("Opening X11 forward connection succeeded");
5901 } else if (typelen
== 15 &&
5902 !memcmp(type
, "forwarded-tcpip", 15)) {
5903 struct ssh_rportfwd pf
, *realpf
;
5906 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5907 pf
.sport
= ssh_pkt_getuint32(pktin
);
5908 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5909 peerport
= ssh_pkt_getuint32(pktin
);
5910 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5911 logeventf(ssh
, "Received remote port %d open request "
5912 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5913 if (realpf
== NULL
) {
5914 error
= "Remote port is not recognised";
5916 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5920 realpf
->pfrec
->addressfamily
);
5921 logeventf(ssh
, "Attempting to forward remote port to "
5922 "%s:%d", realpf
->dhost
, realpf
->dport
);
5924 logeventf(ssh
, "Port open failed: %s", e
);
5925 error
= "Port open failed";
5927 logevent("Forwarded port opened successfully");
5928 c
->type
= CHAN_SOCKDATA
;
5931 } else if (typelen
== 22 &&
5932 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5933 if (!ssh
->agentfwd_enabled
)
5934 error
= "Agent forwarding is not enabled";
5936 c
->type
= CHAN_AGENT
; /* identify channel type */
5937 c
->u
.a
.lensofar
= 0;
5940 error
= "Unsupported channel type requested";
5943 c
->remoteid
= remid
;
5945 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5946 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5947 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5948 ssh2_pkt_addstring(pktout
, error
);
5949 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5950 ssh2_pkt_send(ssh
, pktout
);
5951 logeventf(ssh
, "Rejected channel open: %s", error
);
5954 c
->localid
= alloc_channel_id(ssh
);
5956 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5957 c
->v
.v2
.remwindow
= winsize
;
5958 c
->v
.v2
.remmaxpkt
= pktsize
;
5959 bufchain_init(&c
->v
.v2
.outbuffer
);
5960 add234(ssh
->channels
, c
);
5961 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5962 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5963 ssh2_pkt_adduint32(pktout
, c
->localid
);
5964 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5965 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
5966 ssh2_pkt_send(ssh
, pktout
);
5971 * Handle the SSH2 userauth and connection layers.
5973 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5974 struct Packet
*pktin
)
5976 struct do_ssh2_authconn_state
{
5978 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5980 AUTH_KEYBOARD_INTERACTIVE
5984 AUTH_TYPE_PUBLICKEY
,
5985 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5986 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5988 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5989 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5991 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5992 int tried_pubkey_config
, tried_agent
;
5993 int kbd_inter_running
, kbd_inter_refused
;
5995 int num_prompts
, curr_prompt
, echo
;
6000 void *publickey_blob
;
6001 int publickey_bloblen
;
6002 unsigned char request
[5], *response
, *p
;
6006 char *pkblob
, *alg
, *commentp
;
6007 int pklen
, alglen
, commentlen
;
6008 int siglen
, retlen
, len
;
6009 char *q
, *agentreq
, *ret
;
6011 int num_env
, env_left
, env_ok
;
6012 struct Packet
*pktout
;
6014 crState(do_ssh2_authconn_state
);
6016 crBegin(ssh
->do_ssh2_authconn_crstate
);
6019 * Request userauth protocol, and await a response to it.
6021 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6022 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6023 ssh2_pkt_send(ssh
, s
->pktout
);
6024 crWaitUntilV(pktin
);
6025 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6026 bombout(("Server refused user authentication protocol"));
6031 * We repeat this whole loop, including the username prompt,
6032 * until we manage a successful authentication. If the user
6033 * types the wrong _password_, they can be sent back to the
6034 * beginning to try another username, if this is configured on.
6035 * (If they specify a username in the config, they are never
6036 * asked, even if they do give a wrong password.)
6038 * I think this best serves the needs of
6040 * - the people who have no configuration, no keys, and just
6041 * want to try repeated (username,password) pairs until they
6042 * type both correctly
6044 * - people who have keys and configuration but occasionally
6045 * need to fall back to passwords
6047 * - people with a key held in Pageant, who might not have
6048 * logged in to a particular machine before; so they want to
6049 * type a username, and then _either_ their key will be
6050 * accepted, _or_ they will type a password. If they mistype
6051 * the username they will want to be able to get back and
6054 s
->username
[0] = '\0';
6055 s
->got_username
= FALSE
;
6060 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6062 * We got a username last time round this loop, and
6063 * with change_username turned off we don't try to get
6066 } else if (!*ssh
->cfg
.username
) {
6067 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6068 if (!ssh_get_line("login as: ",
6069 s
->username
, sizeof(s
->username
), FALSE
)) {
6071 * get_line failed to get a username.
6074 logevent("No username provided. Abandoning session.");
6075 ssh
->close_expected
= TRUE
;
6076 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6080 int ret
; /* need not be saved across crReturn */
6081 c_write_str(ssh
, "login as: ");
6083 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6085 crWaitUntilV(!pktin
);
6086 ret
= process_userpass_input(ssh
, in
, inlen
);
6090 c_write_str(ssh
, "\r\n");
6092 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6095 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6096 s
->username
[sizeof(s
->username
)-1] = '\0';
6097 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6098 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6099 c_write_str(ssh
, stuff
);
6103 s
->got_username
= TRUE
;
6106 * Send an authentication request using method "none": (a)
6107 * just in case it succeeds, and (b) so that we know what
6108 * authentication methods we can usefully try next.
6110 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6112 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6113 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6114 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6115 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6116 ssh2_pkt_send(ssh
, s
->pktout
);
6117 s
->type
= AUTH_TYPE_NONE
;
6119 s
->we_are_in
= FALSE
;
6121 s
->tried_pubkey_config
= FALSE
;
6122 s
->tried_agent
= FALSE
;
6123 s
->kbd_inter_running
= FALSE
;
6124 s
->kbd_inter_refused
= FALSE
;
6125 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6126 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6128 logeventf(ssh
, "Reading private key file \"%.150s\"",
6129 filename_to_str(&ssh
->cfg
.keyfile
));
6130 keytype
= key_type(&ssh
->cfg
.keyfile
);
6131 if (keytype
== SSH_KEYTYPE_SSH2
) {
6133 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6134 &s
->publickey_bloblen
, NULL
);
6137 logeventf(ssh
, "Unable to use this key file (%s)",
6138 key_type_to_str(keytype
));
6139 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6141 filename_to_str(&ssh
->cfg
.keyfile
),
6142 key_type_to_str(keytype
));
6143 c_write_str(ssh
, msgbuf
);
6145 s
->publickey_blob
= NULL
;
6148 s
->publickey_blob
= NULL
;
6152 * Wait for the result of the last authentication request.
6155 crWaitUntilV(pktin
);
6156 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6160 * Don't show the banner if we're operating in
6161 * non-verbose non-interactive mode. (It's probably
6162 * a script, which means nobody will read the
6163 * banner _anyway_, and moreover the printing of
6164 * the banner will screw up processing on the
6165 * output of (say) plink.)
6167 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6168 ssh_pkt_getstring(pktin
, &banner
, &size
);
6170 c_write_untrusted(ssh
, banner
, size
);
6172 crWaitUntilV(pktin
);
6174 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6175 logevent("Access granted");
6176 s
->we_are_in
= TRUE
;
6180 if (s
->kbd_inter_running
&&
6181 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6183 * This is either a further set-of-prompts packet
6184 * in keyboard-interactive authentication, or it's
6185 * the same one and we came back here with `gotit'
6186 * set. In the former case, we must reset the
6187 * curr_prompt variable.
6191 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6192 /* FIXME: perhaps we should support this? */
6193 bombout(("PASSWD_CHANGEREQ not yet supported"));
6195 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6196 bombout(("Strange packet received during authentication: type %d",
6204 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6205 * we can look at the string in it and know what we can
6206 * helpfully try next.
6208 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6211 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6212 s
->kbd_inter_running
= FALSE
;
6213 if (!ssh2_pkt_getbool(pktin
)) {
6215 * We have received an unequivocal Access
6216 * Denied. This can translate to a variety of
6219 * - if we'd just tried "none" authentication,
6220 * it's not worth printing anything at all
6222 * - if we'd just tried a public key _offer_,
6223 * the message should be "Server refused our
6224 * key" (or no message at all if the key
6225 * came from Pageant)
6227 * - if we'd just tried anything else, the
6228 * message really should be "Access denied".
6230 * Additionally, if we'd just tried password
6231 * authentication, we should break out of this
6232 * whole loop so as to go back to the username
6233 * prompt (iff we're configured to allow
6234 * username change attempts).
6236 if (s
->type
== AUTH_TYPE_NONE
) {
6238 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6239 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6240 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6241 c_write_str(ssh
, "Server refused our key\r\n");
6242 logevent("Server refused public key");
6243 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6244 /* server declined keyboard-interactive; ignore */
6246 c_write_str(ssh
, "Access denied\r\n");
6247 logevent("Access denied");
6248 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6249 ssh
->cfg
.change_username
) {
6250 /* XXX perhaps we should allow
6251 * keyboard-interactive to do this too? */
6252 s
->we_are_in
= FALSE
;
6257 c_write_str(ssh
, "Further authentication required\r\n");
6258 logevent("Further authentication required");
6262 in_commasep_string("publickey", methods
, methlen
);
6264 in_commasep_string("password", methods
, methlen
);
6265 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6266 in_commasep_string("keyboard-interactive", methods
, methlen
);
6270 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6274 * Most password/passphrase prompts will be
6275 * non-echoing, so we set this to 0 by default.
6276 * Exception is that some keyboard-interactive prompts
6277 * can be echoing, in which case we'll set this to 1.
6281 if (!s
->method
&& s
->can_pubkey
&&
6282 agent_exists() && !s
->tried_agent
) {
6284 * Attempt public-key authentication using Pageant.
6289 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6290 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6292 s
->tried_agent
= TRUE
;
6294 logevent("Pageant is running. Requesting keys.");
6296 /* Request the keys held by the agent. */
6297 PUT_32BIT(s
->request
, 1);
6298 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6299 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6300 ssh_agent_callback
, ssh
)) {
6304 bombout(("Unexpected data from server while"
6305 " waiting for agent response"));
6308 } while (pktin
|| inlen
> 0);
6309 r
= ssh
->agent_response
;
6310 s
->responselen
= ssh
->agent_response_len
;
6312 s
->response
= (unsigned char *) r
;
6313 if (s
->response
&& s
->responselen
>= 5 &&
6314 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6315 s
->p
= s
->response
+ 5;
6316 s
->nkeys
= GET_32BIT(s
->p
);
6320 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6323 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6328 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6331 s
->pklen
= GET_32BIT(s
->p
);
6333 if (s
->publickey_blob
&&
6334 s
->pklen
== s
->publickey_bloblen
&&
6335 !memcmp(s
->p
, s
->publickey_blob
,
6336 s
->publickey_bloblen
)) {
6337 logevent("This key matches configured key file");
6338 s
->tried_pubkey_config
= 1;
6340 s
->pkblob
= (char *)s
->p
;
6342 s
->alglen
= GET_32BIT(s
->pkblob
);
6343 s
->alg
= s
->pkblob
+ 4;
6344 s
->commentlen
= GET_32BIT(s
->p
);
6346 s
->commentp
= (char *)s
->p
;
6347 s
->p
+= s
->commentlen
;
6348 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6349 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6350 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6351 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6352 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6353 ssh2_pkt_addstring_start(s
->pktout
);
6354 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6355 ssh2_pkt_addstring_start(s
->pktout
);
6356 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6357 ssh2_pkt_send(ssh
, s
->pktout
);
6359 crWaitUntilV(pktin
);
6360 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6361 logevent("Key refused");
6365 if (flags
& FLAG_VERBOSE
) {
6366 c_write_str(ssh
, "Authenticating with "
6368 c_write(ssh
, s
->commentp
, s
->commentlen
);
6369 c_write_str(ssh
, "\" from agent\r\n");
6373 * Server is willing to accept the key.
6374 * Construct a SIGN_REQUEST.
6376 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6377 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6378 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6379 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6380 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6381 ssh2_pkt_addstring_start(s
->pktout
);
6382 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6383 ssh2_pkt_addstring_start(s
->pktout
);
6384 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6386 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6387 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6389 s
->len
= 1; /* message type */
6390 s
->len
+= 4 + s
->pklen
; /* key blob */
6391 s
->len
+= 4 + s
->siglen
; /* data to sign */
6392 s
->len
+= 4; /* flags */
6393 s
->agentreq
= snewn(4 + s
->len
, char);
6394 PUT_32BIT(s
->agentreq
, s
->len
);
6395 s
->q
= s
->agentreq
+ 4;
6396 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6397 PUT_32BIT(s
->q
, s
->pklen
);
6399 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6401 PUT_32BIT(s
->q
, s
->siglen
);
6403 /* Now the data to be signed... */
6404 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6405 PUT_32BIT(s
->q
, 20);
6408 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6410 memcpy(s
->q
, s
->pktout
->data
+ 5,
6411 s
->pktout
->length
- 5);
6412 s
->q
+= s
->pktout
->length
- 5;
6413 /* And finally the (zero) flags word. */
6415 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6417 ssh_agent_callback
, ssh
)) {
6421 bombout(("Unexpected data from server"
6422 " while waiting for agent"
6426 } while (pktin
|| inlen
> 0);
6427 vret
= ssh
->agent_response
;
6428 s
->retlen
= ssh
->agent_response_len
;
6433 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6434 logevent("Sending Pageant's response");
6435 ssh2_add_sigblob(ssh
, s
->pktout
,
6436 s
->pkblob
, s
->pklen
,
6438 GET_32BIT(s
->ret
+ 5));
6439 ssh2_pkt_send(ssh
, s
->pktout
);
6444 ("Pageant failed to answer challenge");
6455 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6456 && !s
->tried_pubkey_config
) {
6457 unsigned char *pub_blob
;
6458 char *algorithm
, *comment
;
6461 s
->tried_pubkey_config
= TRUE
;
6463 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6464 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6467 * Try the public key supplied in the configuration.
6469 * First, offer the public blob to see if the server is
6470 * willing to accept it.
6473 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6478 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6479 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6480 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6481 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6482 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6483 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6484 ssh2_pkt_addstring_start(s
->pktout
);
6485 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6487 ssh2_pkt_send(ssh
, s
->pktout
);
6488 logevent("Offered public key");
6490 crWaitUntilV(pktin
);
6491 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6493 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6494 continue; /* key refused; give up on it */
6497 logevent("Offer of public key accepted");
6499 * Actually attempt a serious authentication using
6502 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6503 sprintf(s
->pwprompt
,
6504 "Passphrase for key \"%.100s\": ",
6510 if (flags
& FLAG_VERBOSE
) {
6511 c_write_str(ssh
, "Authenticating with public key \"");
6512 c_write_str(ssh
, comment
);
6513 c_write_str(ssh
, "\"\r\n");
6515 s
->method
= AUTH_PUBLICKEY_FILE
;
6519 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6520 !s
->kbd_inter_running
) {
6521 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6522 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6524 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6525 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6527 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6528 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6529 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6530 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6531 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6532 ssh2_pkt_addstring(s
->pktout
, "");
6533 ssh2_pkt_send(ssh
, s
->pktout
);
6535 crWaitUntilV(pktin
);
6536 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6537 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6539 logevent("Keyboard-interactive authentication refused");
6540 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6541 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6545 s
->kbd_inter_running
= TRUE
;
6549 if (s
->kbd_inter_running
) {
6550 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6551 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6553 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6554 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6556 if (s
->curr_prompt
== 0) {
6558 * We've got a fresh USERAUTH_INFO_REQUEST.
6559 * Display header data, and start going through
6562 char *name
, *inst
, *lang
;
6563 int name_len
, inst_len
, lang_len
;
6565 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6566 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6567 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6569 c_write_untrusted(ssh
, name
, name_len
);
6570 c_write_str(ssh
, "\r\n");
6573 c_write_untrusted(ssh
, inst
, inst_len
);
6574 c_write_str(ssh
, "\r\n");
6576 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6580 * If there are prompts remaining in the packet,
6581 * display one and get a response.
6583 if (s
->curr_prompt
< s
->num_prompts
) {
6587 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6588 if (prompt_len
> 0) {
6589 static const char trunc
[] = "<prompt truncated>: ";
6590 static const int prlen
= sizeof(s
->pwprompt
) -
6592 if (prompt_len
> prlen
) {
6593 memcpy(s
->pwprompt
, prompt
, prlen
);
6594 strcpy(s
->pwprompt
+ prlen
, trunc
);
6596 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6597 s
->pwprompt
[prompt_len
] = '\0';
6601 "<server failed to send prompt>: ");
6603 s
->echo
= ssh2_pkt_getbool(pktin
);
6609 if (!s
->method
&& s
->can_passwd
) {
6610 s
->method
= AUTH_PASSWORD
;
6611 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6612 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6613 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6620 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6621 sizeof(s
->password
), TRUE
)) {
6623 * get_line failed to get a password (for
6624 * example because one was supplied on the
6625 * command line which has already failed to
6628 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6629 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6630 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6632 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6633 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6634 logevent("Unable to authenticate");
6635 connection_fatal(ssh
->frontend
,
6636 "Unable to authenticate");
6637 ssh
->close_expected
= TRUE
;
6638 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6642 int ret
; /* need not be saved across crReturn */
6643 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6646 setup_userpass_input(ssh
, s
->password
,
6647 sizeof(s
->password
), s
->echo
);
6649 crWaitUntilV(!pktin
);
6650 ret
= process_userpass_input(ssh
, in
, inlen
);
6654 c_write_str(ssh
, "\r\n");
6658 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6660 * We have our passphrase. Now try the actual authentication.
6662 struct ssh2_userkey
*key
;
6663 const char *error
= NULL
;
6665 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6667 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6668 if (key
== SSH2_WRONG_PASSPHRASE
) {
6669 c_write_str(ssh
, "Wrong passphrase\r\n");
6670 s
->tried_pubkey_config
= FALSE
;
6672 c_write_str(ssh
, "Unable to load private key (");
6673 c_write_str(ssh
, error
);
6674 c_write_str(ssh
, ")\r\n");
6675 s
->tried_pubkey_config
= TRUE
;
6677 /* Send a spurious AUTH_NONE to return to the top. */
6678 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6679 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6680 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6681 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6682 ssh2_pkt_send(ssh
, s
->pktout
);
6683 s
->type
= AUTH_TYPE_NONE
;
6685 unsigned char *pkblob
, *sigblob
, *sigdata
;
6686 int pkblob_len
, sigblob_len
, sigdata_len
;
6690 * We have loaded the private key and the server
6691 * has announced that it's willing to accept it.
6692 * Hallelujah. Generate a signature and send it.
6694 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6695 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6696 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6697 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6698 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6699 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6700 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6701 ssh2_pkt_addstring_start(s
->pktout
);
6702 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6705 * The data to be signed is:
6709 * followed by everything so far placed in the
6712 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6713 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6715 sigdata
= snewn(sigdata_len
, unsigned char);
6717 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6718 PUT_32BIT(sigdata
+p
, 20);
6721 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6722 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6723 s
->pktout
->length
- 5);
6724 p
+= s
->pktout
->length
- 5;
6725 assert(p
== sigdata_len
);
6726 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6727 sigdata_len
, &sigblob_len
);
6728 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6729 sigblob
, sigblob_len
);
6734 ssh2_pkt_send(ssh
, s
->pktout
);
6735 s
->type
= AUTH_TYPE_PUBLICKEY
;
6736 key
->alg
->freekey(key
->data
);
6738 } else if (s
->method
== AUTH_PASSWORD
) {
6740 * We send the password packet lumped tightly together with
6741 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6742 * string long enough to make the total length of the two
6743 * packets constant. This should ensure that a passive
6744 * listener doing traffic analyis can't work out the length
6747 * For this to work, we need an assumption about the
6748 * maximum length of the password packet. I think 256 is
6749 * pretty conservative. Anyone using a password longer than
6750 * that probably doesn't have much to worry about from
6751 * people who find out how long their password is!
6753 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6754 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6755 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6756 ssh2_pkt_addstring(s
->pktout
, "password");
6757 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6758 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6759 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6760 memset(s
->password
, 0, sizeof(s
->password
));
6761 end_log_omission(ssh
, s
->pktout
);
6762 ssh2_pkt_defer(ssh
, s
->pktout
);
6764 * We'll include a string that's an exact multiple of the
6765 * cipher block size. If the cipher is NULL for some
6766 * reason, we don't do this trick at all because we gain
6769 if (ssh
->cscipher
) {
6772 stringlen
= (256 - ssh
->deferred_len
);
6773 stringlen
+= ssh
->cscipher
->blksize
- 1;
6774 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6777 * Temporarily disable actual compression,
6778 * so we can guarantee to get this string
6779 * exactly the length we want it. The
6780 * compression-disabling routine should
6781 * return an integer indicating how many
6782 * bytes we should adjust our string length
6786 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6788 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6789 ssh2_pkt_addstring_start(s
->pktout
);
6790 for (i
= 0; i
< stringlen
; i
++) {
6791 char c
= (char) random_byte();
6792 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6794 ssh2_pkt_defer(ssh
, s
->pktout
);
6796 ssh_pkt_defersend(ssh
);
6797 logevent("Sent password");
6798 s
->type
= AUTH_TYPE_PASSWORD
;
6799 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6800 if (s
->curr_prompt
== 0) {
6801 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6802 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6804 if (s
->need_pw
) { /* only add pw if we just got one! */
6805 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6806 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6807 memset(s
->password
, 0, sizeof(s
->password
));
6808 end_log_omission(ssh
, s
->pktout
);
6811 if (s
->curr_prompt
>= s
->num_prompts
) {
6812 ssh2_pkt_send(ssh
, s
->pktout
);
6815 * If there are prompts remaining, we set
6816 * `gotit' so that we won't attempt to get
6817 * another packet. Then we go back round the
6818 * loop and will end up retrieving another
6819 * prompt out of the existing packet. Funky or
6824 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6826 c_write_str(ssh
, "No supported authentication methods"
6827 " left to try!\r\n");
6828 logevent("No supported authentications offered."
6830 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6831 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6832 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6833 " methods available");
6834 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6835 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6836 ssh
->close_expected
= TRUE
;
6837 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6841 } while (!s
->we_are_in
);
6844 * Now we're authenticated for the connection protocol. The
6845 * connection protocol will automatically have started at this
6846 * point; there's no need to send SERVICE_REQUEST.
6849 ssh
->channels
= newtree234(ssh_channelcmp
);
6852 * Set up handlers for some connection protocol messages, so we
6853 * don't have to handle them repeatedly in this coroutine.
6855 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6856 ssh2_msg_channel_window_adjust
;
6857 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6858 ssh2_msg_global_request
;
6861 * Create the main session channel.
6863 if (!ssh
->cfg
.ssh_no_shell
) {
6864 ssh
->mainchan
= snew(struct ssh_channel
);
6865 ssh
->mainchan
->ssh
= ssh
;
6866 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6867 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6868 ssh2_pkt_addstring(s
->pktout
, "session");
6869 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6870 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6871 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6872 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6873 ssh2_pkt_send(ssh
, s
->pktout
);
6874 crWaitUntilV(pktin
);
6875 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6876 bombout(("Server refused to open a session"));
6878 /* FIXME: error data comes back in FAILURE packet */
6880 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6881 bombout(("Server's channel confirmation cited wrong channel"));
6884 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6885 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6886 ssh
->mainchan
->closes
= 0;
6887 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6888 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6889 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6890 add234(ssh
->channels
, ssh
->mainchan
);
6891 update_specials_menu(ssh
->frontend
);
6892 logevent("Opened channel for session");
6894 ssh
->mainchan
= NULL
;
6897 * Now we have a channel, make dispatch table entries for
6898 * general channel-based messages.
6900 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6901 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6902 ssh2_msg_channel_data
;
6903 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6904 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6905 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6906 ssh2_msg_channel_open_confirmation
;
6907 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6908 ssh2_msg_channel_open_failure
;
6909 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6910 ssh2_msg_channel_request
;
6911 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6912 ssh2_msg_channel_open
;
6915 * Potentially enable X11 forwarding.
6917 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6918 char proto
[20], data
[64];
6919 logevent("Requesting X11 forwarding");
6920 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6921 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6922 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6923 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6924 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6925 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6926 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6927 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6928 ssh2_pkt_addstring(s
->pktout
, proto
);
6929 ssh2_pkt_addstring(s
->pktout
, data
);
6930 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6931 ssh2_pkt_send(ssh
, s
->pktout
);
6933 crWaitUntilV(pktin
);
6935 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6936 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6937 bombout(("Unexpected response to X11 forwarding request:"
6938 " packet type %d", pktin
->type
));
6941 logevent("X11 forwarding refused");
6943 logevent("X11 forwarding enabled");
6944 ssh
->X11_fwd_enabled
= TRUE
;
6949 * Enable port forwardings.
6951 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6954 * Potentially enable agent forwarding.
6956 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6957 logevent("Requesting OpenSSH-style agent forwarding");
6958 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6959 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6960 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6961 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6962 ssh2_pkt_send(ssh
, s
->pktout
);
6964 crWaitUntilV(pktin
);
6966 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6967 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6968 bombout(("Unexpected response to agent forwarding request:"
6969 " packet type %d", pktin
->type
));
6972 logevent("Agent forwarding refused");
6974 logevent("Agent forwarding enabled");
6975 ssh
->agentfwd_enabled
= TRUE
;
6980 * Now allocate a pty for the session.
6982 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6983 /* Unpick the terminal-speed string. */
6984 /* XXX perhaps we should allow no speeds to be sent. */
6985 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6986 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6987 /* Build the pty request. */
6988 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6989 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6990 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6991 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6992 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6993 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6994 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6995 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6996 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6997 ssh2_pkt_addstring_start(s
->pktout
);
6998 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6999 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7000 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
7001 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7002 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7003 ssh2_pkt_send(ssh
, s
->pktout
);
7004 ssh
->state
= SSH_STATE_INTERMED
;
7006 crWaitUntilV(pktin
);
7008 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7009 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7010 bombout(("Unexpected response to pty request:"
7011 " packet type %d", pktin
->type
));
7014 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7015 ssh
->editing
= ssh
->echoing
= 1;
7017 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7018 ssh
->ospeed
, ssh
->ispeed
);
7021 ssh
->editing
= ssh
->echoing
= 1;
7025 * Send environment variables.
7027 * Simplest thing here is to send all the requests at once, and
7028 * then wait for a whole bunch of successes or failures.
7030 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7031 char *e
= ssh
->cfg
.environmt
;
7032 char *var
, *varend
, *val
;
7038 while (*e
&& *e
!= '\t') e
++;
7040 if (*e
== '\t') e
++;
7045 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7046 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7047 ssh2_pkt_addstring(s
->pktout
, "env");
7048 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7049 ssh2_pkt_addstring_start(s
->pktout
);
7050 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7051 ssh2_pkt_addstring(s
->pktout
, val
);
7052 ssh2_pkt_send(ssh
, s
->pktout
);
7057 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7060 s
->env_left
= s
->num_env
;
7062 while (s
->env_left
> 0) {
7063 crWaitUntilV(pktin
);
7065 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7066 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7067 bombout(("Unexpected response to environment request:"
7068 " packet type %d", pktin
->type
));
7078 if (s
->env_ok
== s
->num_env
) {
7079 logevent("All environment variables successfully set");
7080 } else if (s
->env_ok
== 0) {
7081 logevent("All environment variables refused");
7082 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7084 logeventf(ssh
, "%d environment variables refused",
7085 s
->num_env
- s
->env_ok
);
7086 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7091 * Start a shell or a remote command. We may have to attempt
7092 * this twice if the config data has provided a second choice
7095 if (ssh
->mainchan
) while (1) {
7099 if (ssh
->fallback_cmd
) {
7100 subsys
= ssh
->cfg
.ssh_subsys2
;
7101 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7103 subsys
= ssh
->cfg
.ssh_subsys
;
7104 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7107 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7108 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7110 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7111 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7112 ssh2_pkt_addstring(s
->pktout
, cmd
);
7114 ssh2_pkt_addstring(s
->pktout
, "exec");
7115 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7116 ssh2_pkt_addstring(s
->pktout
, cmd
);
7118 ssh2_pkt_addstring(s
->pktout
, "shell");
7119 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7121 ssh2_pkt_send(ssh
, s
->pktout
);
7123 crWaitUntilV(pktin
);
7125 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7126 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7127 bombout(("Unexpected response to shell/command request:"
7128 " packet type %d", pktin
->type
));
7132 * We failed to start the command. If this is the
7133 * fallback command, we really are finished; if it's
7134 * not, and if the fallback command exists, try falling
7135 * back to it before complaining.
7137 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7138 logevent("Primary command failed; attempting fallback");
7139 ssh
->fallback_cmd
= TRUE
;
7142 bombout(("Server refused to start a shell/command"));
7145 logevent("Started a shell/command");
7150 ssh
->state
= SSH_STATE_SESSION
;
7151 if (ssh
->size_needed
)
7152 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7153 if (ssh
->eof_needed
)
7154 ssh_special(ssh
, TS_EOF
);
7160 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7165 s
->try_send
= FALSE
;
7169 * _All_ the connection-layer packets we expect to
7170 * receive are now handled by the dispatch table.
7171 * Anything that reaches here must be bogus.
7174 bombout(("Strange packet received: type %d", pktin
->type
));
7176 } else if (ssh
->mainchan
) {
7178 * We have spare data. Add it to the channel buffer.
7180 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7185 struct ssh_channel
*c
;
7187 * Try to send data on all channels if we can.
7189 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7192 continue; /* don't send on closing channels */
7193 bufsize
= ssh2_try_send(c
);
7196 case CHAN_MAINSESSION
:
7197 /* stdin need not receive an unthrottle
7198 * notification since it will be polled */
7201 x11_unthrottle(c
->u
.x11
.s
);
7204 /* agent sockets are request/response and need no
7205 * buffer management */
7208 pfd_unthrottle(c
->u
.pfd
.s
);
7220 * Handlers for SSH2 messages that might arrive at any moment.
7222 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7224 /* log reason code in disconnect message */
7226 int nowlen
, reason
, msglen
;
7228 reason
= ssh_pkt_getuint32(pktin
);
7229 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7231 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7232 buf
= dupprintf("Received disconnect message (%s)",
7233 ssh2_disconnect_reasons
[reason
]);
7235 buf
= dupprintf("Received disconnect message (unknown"
7236 " type %d)", reason
);
7240 buf
= dupprintf("Disconnection message text: %n%.*s",
7241 &nowlen
, msglen
, msg
);
7243 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7245 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7246 ssh2_disconnect_reasons
[reason
] : "unknown",
7251 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7253 /* log the debug message */
7258 /* XXX maybe we should actually take notice of this */
7259 always_display
= ssh2_pkt_getbool(pktin
);
7260 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7262 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7267 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7269 struct Packet
*pktout
;
7270 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7271 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7273 * UNIMPLEMENTED messages MUST appear in the same order as the
7274 * messages they respond to. Hence, never queue them.
7276 ssh2_pkt_send_noqueue(ssh
, pktout
);
7280 * Handle the top-level SSH2 protocol.
7282 static void ssh2_protocol_setup(Ssh ssh
)
7287 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7289 for (i
= 0; i
< 256; i
++)
7290 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7293 * Any message we actually understand, we set to NULL so that
7294 * the coroutines will get it.
7296 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7297 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7298 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7299 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7300 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7301 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7302 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7303 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7304 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7305 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7306 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7307 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7308 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7309 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7310 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7311 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7312 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7313 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7314 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7315 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7316 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7317 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7318 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7319 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7320 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7321 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7322 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7323 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7324 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7325 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7326 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7327 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7328 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7331 * These special message types we install handlers for.
7333 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7334 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7335 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7338 static void ssh2_timer(void *ctx
, long now
)
7342 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7343 now
- ssh
->next_rekey
>= 0) {
7344 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7348 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7349 struct Packet
*pktin
)
7351 if (ssh
->state
== SSH_STATE_CLOSED
)
7355 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7356 if (!ssh
->kex_in_progress
&&
7357 ssh
->max_data_size
!= 0 &&
7358 ssh
->incoming_data_size
> ssh
->max_data_size
)
7359 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7362 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7363 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7367 if (!ssh
->protocol_initial_phase_done
||
7368 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7369 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7370 !ssh
->protocol_initial_phase_done
) {
7371 ssh
->protocol_initial_phase_done
= TRUE
;
7373 * Allow authconn to initialise itself.
7375 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7378 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7383 * Called to set up the connection.
7385 * Returns an error message, or NULL on success.
7387 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7389 char *host
, int port
, char **realhost
, int nodelay
,
7395 ssh
= snew(struct ssh_tag
);
7396 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7397 ssh
->version
= 0; /* when not ready yet */
7400 ssh
->v1_cipher_ctx
= NULL
;
7401 ssh
->crcda_ctx
= NULL
;
7402 ssh
->cscipher
= NULL
;
7403 ssh
->cs_cipher_ctx
= NULL
;
7404 ssh
->sccipher
= NULL
;
7405 ssh
->sc_cipher_ctx
= NULL
;
7407 ssh
->cs_mac_ctx
= NULL
;
7409 ssh
->sc_mac_ctx
= NULL
;
7411 ssh
->cs_comp_ctx
= NULL
;
7413 ssh
->sc_comp_ctx
= NULL
;
7415 ssh
->kex_ctx
= NULL
;
7416 ssh
->hostkey
= NULL
;
7418 ssh
->close_expected
= FALSE
;
7419 ssh
->state
= SSH_STATE_PREPACKET
;
7420 ssh
->size_needed
= FALSE
;
7421 ssh
->eof_needed
= FALSE
;
7424 ssh
->deferred_send_data
= NULL
;
7425 ssh
->deferred_len
= 0;
7426 ssh
->deferred_size
= 0;
7427 ssh
->fallback_cmd
= 0;
7429 ssh
->x11auth
= NULL
;
7430 ssh
->v1_compressing
= FALSE
;
7431 ssh
->v2_outgoing_sequence
= 0;
7432 ssh
->ssh1_rdpkt_crstate
= 0;
7433 ssh
->ssh2_rdpkt_crstate
= 0;
7434 ssh
->do_ssh_init_crstate
= 0;
7435 ssh
->ssh_gotdata_crstate
= 0;
7436 ssh
->do_ssh1_connection_crstate
= 0;
7437 ssh
->do_ssh1_login_crstate
= 0;
7438 ssh
->do_ssh2_transport_crstate
= 0;
7439 ssh
->do_ssh2_authconn_crstate
= 0;
7440 ssh
->do_ssh_init_state
= NULL
;
7441 ssh
->do_ssh1_login_state
= NULL
;
7442 ssh
->do_ssh2_transport_state
= NULL
;
7443 ssh
->do_ssh2_authconn_state
= NULL
;
7444 ssh
->mainchan
= NULL
;
7445 ssh
->throttled_all
= 0;
7446 ssh
->v1_stdout_throttling
= 0;
7448 ssh
->queuelen
= ssh
->queuesize
= 0;
7449 ssh
->queueing
= FALSE
;
7450 ssh
->qhead
= ssh
->qtail
= NULL
;
7451 ssh
->deferred_rekey_reason
= NULL
;
7453 *backend_handle
= ssh
;
7456 if (crypto_startup() == 0)
7457 return "Microsoft high encryption pack not installed!";
7460 ssh
->frontend
= frontend_handle
;
7461 ssh
->term_width
= ssh
->cfg
.width
;
7462 ssh
->term_height
= ssh
->cfg
.height
;
7464 ssh
->channels
= NULL
;
7465 ssh
->rportfwds
= NULL
;
7466 ssh
->portfwds
= NULL
;
7471 ssh
->v1_throttle_count
= 0;
7472 ssh
->overall_bufsize
= 0;
7473 ssh
->fallback_cmd
= 0;
7475 ssh
->protocol
= NULL
;
7477 ssh
->protocol_initial_phase_done
= FALSE
;
7481 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7482 ssh
->deferred_data_size
= 0L;
7483 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7484 ssh
->kex_in_progress
= FALSE
;
7486 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7495 static void ssh_free(void *handle
)
7497 Ssh ssh
= (Ssh
) handle
;
7498 struct ssh_channel
*c
;
7499 struct ssh_rportfwd
*pf
;
7501 if (ssh
->v1_cipher_ctx
)
7502 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7503 if (ssh
->cs_cipher_ctx
)
7504 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7505 if (ssh
->sc_cipher_ctx
)
7506 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7507 if (ssh
->cs_mac_ctx
)
7508 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7509 if (ssh
->sc_mac_ctx
)
7510 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7511 if (ssh
->cs_comp_ctx
) {
7513 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7515 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7517 if (ssh
->sc_comp_ctx
) {
7519 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7521 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7524 dh_cleanup(ssh
->kex_ctx
);
7525 sfree(ssh
->savedhost
);
7527 while (ssh
->queuelen
-- > 0)
7528 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7531 while (ssh
->qhead
) {
7532 struct queued_handler
*qh
= ssh
->qhead
;
7533 ssh
->qhead
= qh
->next
;
7536 ssh
->qhead
= ssh
->qtail
= NULL
;
7538 if (ssh
->channels
) {
7539 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7542 if (c
->u
.x11
.s
!= NULL
)
7543 x11_close(c
->u
.x11
.s
);
7546 if (c
->u
.pfd
.s
!= NULL
)
7547 pfd_close(c
->u
.pfd
.s
);
7552 freetree234(ssh
->channels
);
7553 ssh
->channels
= NULL
;
7556 if (ssh
->rportfwds
) {
7557 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7559 freetree234(ssh
->rportfwds
);
7560 ssh
->rportfwds
= NULL
;
7562 sfree(ssh
->deferred_send_data
);
7564 x11_free_auth(ssh
->x11auth
);
7565 sfree(ssh
->do_ssh_init_state
);
7566 sfree(ssh
->do_ssh1_login_state
);
7567 sfree(ssh
->do_ssh2_transport_state
);
7568 sfree(ssh
->do_ssh2_authconn_state
);
7569 if (ssh
->crcda_ctx
) {
7570 crcda_free_context(ssh
->crcda_ctx
);
7571 ssh
->crcda_ctx
= NULL
;
7574 ssh_do_close(ssh
, TRUE
);
7575 expire_timer_context(ssh
);
7577 pinger_free(ssh
->pinger
);
7584 * Reconfigure the SSH backend.
7586 static void ssh_reconfig(void *handle
, Config
*cfg
)
7588 Ssh ssh
= (Ssh
) handle
;
7589 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7590 unsigned long old_max_data_size
;
7592 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7593 ssh_setup_portfwd(ssh
, cfg
);
7595 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7596 cfg
->ssh_rekey_time
!= 0) {
7597 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7598 long now
= GETTICKCOUNT();
7600 if (new_next
- now
< 0) {
7601 rekeying
= "timeout shortened";
7603 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7607 old_max_data_size
= ssh
->max_data_size
;
7608 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7609 if (old_max_data_size
!= ssh
->max_data_size
&&
7610 ssh
->max_data_size
!= 0) {
7611 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7612 ssh
->incoming_data_size
> ssh
->max_data_size
)
7613 rekeying
= "data limit lowered";
7616 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7617 rekeying
= "compression setting changed";
7618 rekey_mandatory
= TRUE
;
7621 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7622 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7623 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7624 rekeying
= "cipher settings changed";
7625 rekey_mandatory
= TRUE
;
7628 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7631 if (!ssh
->kex_in_progress
) {
7632 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7633 } else if (rekey_mandatory
) {
7634 ssh
->deferred_rekey_reason
= rekeying
;
7640 * Called to send data down the Telnet connection.
7642 static int ssh_send(void *handle
, char *buf
, int len
)
7644 Ssh ssh
= (Ssh
) handle
;
7646 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7649 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7651 return ssh_sendbuffer(ssh
);
7655 * Called to query the current amount of buffered stdin data.
7657 static int ssh_sendbuffer(void *handle
)
7659 Ssh ssh
= (Ssh
) handle
;
7662 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7666 * If the SSH socket itself has backed up, add the total backup
7667 * size on that to any individual buffer on the stdin channel.
7670 if (ssh
->throttled_all
)
7671 override_value
= ssh
->overall_bufsize
;
7673 if (ssh
->version
== 1) {
7674 return override_value
;
7675 } else if (ssh
->version
== 2) {
7676 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7677 return override_value
;
7679 return (override_value
+
7680 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7687 * Called to set the size of the window from SSH's POV.
7689 static void ssh_size(void *handle
, int width
, int height
)
7691 Ssh ssh
= (Ssh
) handle
;
7692 struct Packet
*pktout
;
7694 ssh
->term_width
= width
;
7695 ssh
->term_height
= height
;
7697 switch (ssh
->state
) {
7698 case SSH_STATE_BEFORE_SIZE
:
7699 case SSH_STATE_PREPACKET
:
7700 case SSH_STATE_CLOSED
:
7701 break; /* do nothing */
7702 case SSH_STATE_INTERMED
:
7703 ssh
->size_needed
= TRUE
; /* buffer for later */
7705 case SSH_STATE_SESSION
:
7706 if (!ssh
->cfg
.nopty
) {
7707 if (ssh
->version
== 1) {
7708 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7709 PKT_INT
, ssh
->term_height
,
7710 PKT_INT
, ssh
->term_width
,
7711 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7712 } else if (ssh
->mainchan
) {
7713 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7714 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7715 ssh2_pkt_addstring(pktout
, "window-change");
7716 ssh2_pkt_addbool(pktout
, 0);
7717 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7718 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7719 ssh2_pkt_adduint32(pktout
, 0);
7720 ssh2_pkt_adduint32(pktout
, 0);
7721 ssh2_pkt_send(ssh
, pktout
);
7729 * Return a list of the special codes that make sense in this
7732 static const struct telnet_special
*ssh_get_specials(void *handle
)
7734 static const struct telnet_special ssh1_ignore_special
[] = {
7735 {"IGNORE message", TS_NOP
}
7737 static const struct telnet_special ssh2_transport_specials
[] = {
7738 {"IGNORE message", TS_NOP
},
7739 {"Repeat key exchange", TS_REKEY
},
7741 static const struct telnet_special ssh2_session_specials
[] = {
7744 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7745 * They include all the ISO C signals, but are a subset of the POSIX
7746 * required signals. */
7747 {"SIGINT (Interrupt)", TS_SIGINT
},
7748 {"SIGTERM (Terminate)", TS_SIGTERM
},
7749 {"SIGKILL (Kill)", TS_SIGKILL
},
7750 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7751 {"SIGHUP (Hangup)", TS_SIGHUP
},
7752 {"More signals", TS_SUBMENU
},
7753 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7754 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7755 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7756 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7759 static const struct telnet_special specials_end
[] = {
7762 /* XXX review this length for any changes: */
7763 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7764 lenof(ssh2_session_specials
) +
7765 lenof(specials_end
)];
7766 Ssh ssh
= (Ssh
) handle
;
7768 #define ADD_SPECIALS(name) \
7770 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7771 memcpy(&ssh_specials[i], name, sizeof name); \
7775 if (ssh
->version
== 1) {
7776 /* Don't bother offering IGNORE if we've decided the remote
7777 * won't cope with it, since we wouldn't bother sending it if
7779 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7780 ADD_SPECIALS(ssh1_ignore_special
);
7781 } else if (ssh
->version
== 2) {
7782 ADD_SPECIALS(ssh2_transport_specials
);
7784 ADD_SPECIALS(ssh2_session_specials
);
7785 } /* else we're not ready yet */
7788 ADD_SPECIALS(specials_end
);
7789 return ssh_specials
;
7797 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7798 * can send an EOF and collect resulting output (e.g. `plink
7801 static void ssh_special(void *handle
, Telnet_Special code
)
7803 Ssh ssh
= (Ssh
) handle
;
7804 struct Packet
*pktout
;
7806 if (code
== TS_EOF
) {
7807 if (ssh
->state
!= SSH_STATE_SESSION
) {
7809 * Buffer the EOF in case we are pre-SESSION, so we can
7810 * send it as soon as we reach SESSION.
7813 ssh
->eof_needed
= TRUE
;
7816 if (ssh
->version
== 1) {
7817 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7818 } else if (ssh
->mainchan
) {
7819 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7820 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7821 ssh2_pkt_send(ssh
, pktout
);
7823 logevent("Sent EOF message");
7824 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7825 if (ssh
->state
== SSH_STATE_CLOSED
7826 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7827 if (ssh
->version
== 1) {
7828 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7829 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7831 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7832 ssh2_pkt_addstring_start(pktout
);
7833 ssh2_pkt_send_noqueue(ssh
, pktout
);
7835 } else if (code
== TS_REKEY
) {
7836 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7837 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
7839 } else if (code
== TS_BRK
) {
7840 if (ssh
->state
== SSH_STATE_CLOSED
7841 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7842 if (ssh
->version
== 1) {
7843 logevent("Unable to send BREAK signal in SSH1");
7844 } else if (ssh
->mainchan
) {
7845 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7846 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7847 ssh2_pkt_addstring(pktout
, "break");
7848 ssh2_pkt_addbool(pktout
, 0);
7849 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7850 ssh2_pkt_send(ssh
, pktout
);
7853 /* Is is a POSIX signal? */
7854 char *signame
= NULL
;
7855 if (code
== TS_SIGABRT
) signame
= "ABRT";
7856 if (code
== TS_SIGALRM
) signame
= "ALRM";
7857 if (code
== TS_SIGFPE
) signame
= "FPE";
7858 if (code
== TS_SIGHUP
) signame
= "HUP";
7859 if (code
== TS_SIGILL
) signame
= "ILL";
7860 if (code
== TS_SIGINT
) signame
= "INT";
7861 if (code
== TS_SIGKILL
) signame
= "KILL";
7862 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7863 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7864 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7865 if (code
== TS_SIGTERM
) signame
= "TERM";
7866 if (code
== TS_SIGUSR1
) signame
= "USR1";
7867 if (code
== TS_SIGUSR2
) signame
= "USR2";
7868 /* The SSH-2 protocol does in principle support arbitrary named
7869 * signals, including signame@domain, but we don't support those. */
7871 /* It's a signal. */
7872 if (ssh
->version
== 2 && ssh
->mainchan
) {
7873 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7874 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7875 ssh2_pkt_addstring(pktout
, "signal");
7876 ssh2_pkt_addbool(pktout
, 0);
7877 ssh2_pkt_addstring(pktout
, signame
);
7878 ssh2_pkt_send(ssh
, pktout
);
7879 logeventf(ssh
, "Sent signal SIG%s", signame
);
7882 /* Never heard of it. Do nothing */
7887 void *new_sock_channel(void *handle
, Socket s
)
7889 Ssh ssh
= (Ssh
) handle
;
7890 struct ssh_channel
*c
;
7891 c
= snew(struct ssh_channel
);
7895 c
->remoteid
= -1; /* to be set when open confirmed */
7896 c
->localid
= alloc_channel_id(ssh
);
7898 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7900 bufchain_init(&c
->v
.v2
.outbuffer
);
7901 add234(ssh
->channels
, c
);
7907 * This is called when stdout/stderr (the entity to which
7908 * from_backend sends data) manages to clear some backlog.
7910 static void ssh_unthrottle(void *handle
, int bufsize
)
7912 Ssh ssh
= (Ssh
) handle
;
7913 if (ssh
->version
== 1) {
7914 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7915 ssh
->v1_stdout_throttling
= 0;
7916 ssh1_throttle(ssh
, -1);
7919 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7920 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7924 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7926 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7928 struct Packet
*pktout
;
7930 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7932 if (ssh
->version
== 1) {
7933 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7934 PKT_INT
, c
->localid
,
7937 /* PKT_STR, <org:orgport>, */
7940 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7941 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7942 ssh2_pkt_adduint32(pktout
, c
->localid
);
7943 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7944 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7945 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7946 ssh2_pkt_addstring(pktout
, hostname
);
7947 ssh2_pkt_adduint32(pktout
, port
);
7949 * We make up values for the originator data; partly it's
7950 * too much hassle to keep track, and partly I'm not
7951 * convinced the server should be told details like that
7952 * about my local network configuration.
7954 ssh2_pkt_addstring(pktout
, "client-side-connection");
7955 ssh2_pkt_adduint32(pktout
, 0);
7956 ssh2_pkt_send(ssh
, pktout
);
7960 static Socket
ssh_socket(void *handle
)
7962 Ssh ssh
= (Ssh
) handle
;
7966 static int ssh_sendok(void *handle
)
7968 Ssh ssh
= (Ssh
) handle
;
7969 return ssh
->send_ok
;
7972 static int ssh_ldisc(void *handle
, int option
)
7974 Ssh ssh
= (Ssh
) handle
;
7975 if (option
== LD_ECHO
)
7976 return ssh
->echoing
;
7977 if (option
== LD_EDIT
)
7978 return ssh
->editing
;
7982 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7984 Ssh ssh
= (Ssh
) handle
;
7988 static void ssh_provide_logctx(void *handle
, void *logctx
)
7990 Ssh ssh
= (Ssh
) handle
;
7991 ssh
->logctx
= logctx
;
7994 static int ssh_return_exitcode(void *handle
)
7996 Ssh ssh
= (Ssh
) handle
;
8000 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8004 * cfg_info for SSH is the currently running version of the
8005 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8007 static int ssh_cfg_info(void *handle
)
8009 Ssh ssh
= (Ssh
) handle
;
8010 return ssh
->version
;
8014 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8015 * that fails. This variable is the means by which scp.c can reach
8016 * into the SSH code and find out which one it got.
8018 extern int ssh_fallback_cmd(void *handle
)
8020 Ssh ssh
= (Ssh
) handle
;
8021 return ssh
->fallback_cmd
;
8024 Backend ssh_backend
= {
8034 ssh_return_exitcode
,