17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_KEX_MASK 0x000F
110 #define SSH2_PKTCTX_PUBLICKEY 0x0010
111 #define SSH2_PKTCTX_PASSWORD 0x0020
112 #define SSH2_PKTCTX_KBDINTER 0x0040
113 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
115 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
131 static const char *const ssh2_disconnect_reasons
[] = {
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
150 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
155 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
158 * Various remote-bug flags.
160 #define BUG_CHOKES_ON_SSH1_IGNORE 1
161 #define BUG_SSH2_HMAC 2
162 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
163 #define BUG_CHOKES_ON_RSA 8
164 #define BUG_SSH2_RSA_PADDING 16
165 #define BUG_SSH2_DERIVEKEY 32
166 #define BUG_SSH2_REKEY 64
167 #define BUG_SSH2_PK_SESSIONID 128
169 #define translate(x) if (type == x) return #x
170 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
171 static char *ssh1_pkt_type(int type
)
173 translate(SSH1_MSG_DISCONNECT
);
174 translate(SSH1_SMSG_PUBLIC_KEY
);
175 translate(SSH1_CMSG_SESSION_KEY
);
176 translate(SSH1_CMSG_USER
);
177 translate(SSH1_CMSG_AUTH_RSA
);
178 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
179 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
180 translate(SSH1_CMSG_AUTH_PASSWORD
);
181 translate(SSH1_CMSG_REQUEST_PTY
);
182 translate(SSH1_CMSG_WINDOW_SIZE
);
183 translate(SSH1_CMSG_EXEC_SHELL
);
184 translate(SSH1_CMSG_EXEC_CMD
);
185 translate(SSH1_SMSG_SUCCESS
);
186 translate(SSH1_SMSG_FAILURE
);
187 translate(SSH1_CMSG_STDIN_DATA
);
188 translate(SSH1_SMSG_STDOUT_DATA
);
189 translate(SSH1_SMSG_STDERR_DATA
);
190 translate(SSH1_CMSG_EOF
);
191 translate(SSH1_SMSG_EXIT_STATUS
);
192 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
193 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
194 translate(SSH1_MSG_CHANNEL_DATA
);
195 translate(SSH1_MSG_CHANNEL_CLOSE
);
196 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
197 translate(SSH1_SMSG_X11_OPEN
);
198 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
199 translate(SSH1_MSG_PORT_OPEN
);
200 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
201 translate(SSH1_SMSG_AGENT_OPEN
);
202 translate(SSH1_MSG_IGNORE
);
203 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
204 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
205 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
206 translate(SSH1_MSG_DEBUG
);
207 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
208 translate(SSH1_CMSG_AUTH_TIS
);
209 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
210 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
211 translate(SSH1_CMSG_AUTH_CCARD
);
212 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
213 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
216 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
218 translate(SSH2_MSG_DISCONNECT
);
219 translate(SSH2_MSG_IGNORE
);
220 translate(SSH2_MSG_UNIMPLEMENTED
);
221 translate(SSH2_MSG_DEBUG
);
222 translate(SSH2_MSG_SERVICE_REQUEST
);
223 translate(SSH2_MSG_SERVICE_ACCEPT
);
224 translate(SSH2_MSG_KEXINIT
);
225 translate(SSH2_MSG_NEWKEYS
);
226 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP
);
227 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP
);
228 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
231 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
232 translate(SSH2_MSG_USERAUTH_REQUEST
);
233 translate(SSH2_MSG_USERAUTH_FAILURE
);
234 translate(SSH2_MSG_USERAUTH_SUCCESS
);
235 translate(SSH2_MSG_USERAUTH_BANNER
);
236 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
237 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
238 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
239 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
240 translate(SSH2_MSG_GLOBAL_REQUEST
);
241 translate(SSH2_MSG_REQUEST_SUCCESS
);
242 translate(SSH2_MSG_REQUEST_FAILURE
);
243 translate(SSH2_MSG_CHANNEL_OPEN
);
244 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
245 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
246 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
247 translate(SSH2_MSG_CHANNEL_DATA
);
248 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
249 translate(SSH2_MSG_CHANNEL_EOF
);
250 translate(SSH2_MSG_CHANNEL_CLOSE
);
251 translate(SSH2_MSG_CHANNEL_REQUEST
);
252 translate(SSH2_MSG_CHANNEL_SUCCESS
);
253 translate(SSH2_MSG_CHANNEL_FAILURE
);
259 #define GET_32BIT(cp) \
260 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
261 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
262 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
263 ((unsigned long)(unsigned char)(cp)[3]))
265 #define PUT_32BIT(cp, value) { \
266 (cp)[0] = (unsigned char)((value) >> 24); \
267 (cp)[1] = (unsigned char)((value) >> 16); \
268 (cp)[2] = (unsigned char)((value) >> 8); \
269 (cp)[3] = (unsigned char)(value); }
271 /* Enumeration values for fields in SSH-1 packets */
273 PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
,
274 /* These values are for communicating relevant semantics of
275 * fields to the packet logging code. */
276 PKTT_OTHER
, PKTT_PASSWORD
, PKTT_DATA
280 * Coroutine mechanics for the sillier bits of the code. If these
281 * macros look impenetrable to you, you might find it helpful to
284 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
286 * which explains the theory behind these macros.
288 * In particular, if you are getting `case expression not constant'
289 * errors when building with MS Visual Studio, this is because MS's
290 * Edit and Continue debugging feature causes their compiler to
291 * violate ANSI C. To disable Edit and Continue debugging:
293 * - right-click ssh.c in the FileView
295 * - select the C/C++ tab and the General category
296 * - under `Debug info:', select anything _other_ than `Program
297 * Database for Edit and Continue'.
299 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
302 if (!ssh->t) ssh->t = snew(struct t); \
304 #define crFinish(z) } *crLine = 0; return (z); }
305 #define crFinishV } *crLine = 0; return; }
306 #define crReturn(z) \
308 *crLine =__LINE__; return (z); case __LINE__:;\
312 *crLine=__LINE__; return; case __LINE__:;\
314 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
315 #define crStopV do{ *crLine = 0; return; }while(0)
316 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
317 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
319 typedef struct ssh_tag
*Ssh
;
322 static struct Packet
*ssh2_pkt_init(int pkt_type
);
323 static void ssh2_pkt_addbool(struct Packet
*, unsigned char value
);
324 static void ssh2_pkt_adduint32(struct Packet
*, unsigned long value
);
325 static void ssh2_pkt_addstring_start(struct Packet
*);
326 static void ssh2_pkt_addstring_str(struct Packet
*, char *data
);
327 static void ssh2_pkt_addstring_data(struct Packet
*, char *data
, int len
);
328 static void ssh2_pkt_addstring(struct Packet
*, char *data
);
329 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
330 static void ssh2_pkt_addmp(struct Packet
*, Bignum b
);
331 static int ssh2_pkt_construct(Ssh
, struct Packet
*);
332 static void ssh2_pkt_send(Ssh
, struct Packet
*);
333 static void ssh2_pkt_send_noqueue(Ssh
, struct Packet
*);
334 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
335 struct Packet
*pktin
);
336 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
337 struct Packet
*pktin
);
340 * Buffer management constants. There are several of these for
341 * various different purposes:
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
360 #define SSH1_BUFFER_LIMIT 32768
361 #define SSH_MAX_BACKLOG 32768
362 #define OUR_V2_WINSIZE 16384
363 #define OUR_V2_MAXPKT 0x4000UL
365 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
367 static void *nullmac_make_context(void)
371 static void nullmac_free_context(void *handle
)
374 static void nullmac_key(void *handle
, unsigned char *key
)
377 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
381 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
386 const static struct ssh_mac ssh_mac_none
= {
387 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
388 nullmac_generate
, nullmac_verify
, "none", 0
390 const static struct ssh_mac
*macs
[] = {
391 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
393 const static struct ssh_mac
*buggymacs
[] = {
394 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
397 static void *ssh_comp_none_init(void)
401 static void ssh_comp_none_cleanup(void *handle
)
404 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
405 unsigned char **outblock
, int *outlen
)
409 static int ssh_comp_none_disable(void *handle
)
413 const static struct ssh_compress ssh_comp_none
= {
415 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
416 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
417 ssh_comp_none_disable
, NULL
419 extern const struct ssh_compress ssh_zlib
;
420 const static struct ssh_compress
*compressions
[] = {
421 &ssh_zlib
, &ssh_comp_none
424 enum { /* channel types */
429 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
433 * 2-3-4 tree storing channels.
436 Ssh ssh
; /* pointer back to main context */
437 unsigned remoteid
, localid
;
439 /* True if we opened this channel but server hasn't confirmed. */
442 * In SSH1, this value contains four bits:
444 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
445 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
447 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
449 * A channel is completely finished with when all four bits are set.
453 struct ssh1_data_channel
{
456 struct ssh2_data_channel
{
458 unsigned remwindow
, remmaxpkt
;
463 struct ssh_agent_channel
{
464 unsigned char *message
;
465 unsigned char msglen
[4];
466 unsigned lensofar
, totallen
;
468 struct ssh_x11_channel
{
471 struct ssh_pfd_channel
{
478 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
479 * 2 use this structure in different ways, reflecting SSH 2's
480 * altogether saner approach to port forwarding.
482 * In SSH 1, you arrange a remote forwarding by sending the server
483 * the remote port number, and the local destination host:port.
484 * When a connection comes in, the server sends you back that
485 * host:port pair, and you connect to it. This is a ready-made
486 * security hole if you're not on the ball: a malicious server
487 * could send you back _any_ host:port pair, so if you trustingly
488 * connect to the address it gives you then you've just opened the
489 * entire inside of your corporate network just by connecting
490 * through it to a dodgy SSH server. Hence, we must store a list of
491 * host:port pairs we _are_ trying to forward to, and reject a
492 * connection request from the server if it's not in the list.
494 * In SSH 2, each side of the connection minds its own business and
495 * doesn't send unnecessary information to the other. You arrange a
496 * remote forwarding by sending the server just the remote port
497 * number. When a connection comes in, the server tells you which
498 * of its ports was connected to; and _you_ have to remember what
499 * local host:port pair went with that port number.
501 * Hence, in SSH 1 this structure is indexed by destination
502 * host:port pair, whereas in SSH 2 it is indexed by source port.
504 struct ssh_portfwd
; /* forward declaration */
506 struct ssh_rportfwd
{
507 unsigned sport
, dport
;
510 struct ssh_portfwd
*pfrec
;
512 #define free_rportfwd(pf) ( \
513 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
516 * Separately to the rportfwd tree (which is for looking up port
517 * open requests from the server), a tree of _these_ structures is
518 * used to keep track of all the currently open port forwardings,
519 * so that we can reconfigure in mid-session if the user requests
523 enum { DESTROY
, KEEP
, CREATE
} status
;
525 unsigned sport
, dport
;
528 struct ssh_rportfwd
*remote
;
532 #define free_portfwd(pf) ( \
533 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
534 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
538 long forcepad
; /* Force padding to at least this length */
540 unsigned long sequence
;
545 long encrypted_len
; /* for SSH2 total-size counting */
548 * State associated with packet logging
552 struct logblank_t
*blanks
;
555 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
556 struct Packet
*pktin
);
557 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
558 struct Packet
*pktin
);
559 static void ssh1_protocol_setup(Ssh ssh
);
560 static void ssh2_protocol_setup(Ssh ssh
);
561 static void ssh_size(void *handle
, int width
, int height
);
562 static void ssh_special(void *handle
, Telnet_Special
);
563 static int ssh2_try_send(struct ssh_channel
*c
);
564 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
565 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
566 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
567 static int ssh_sendbuffer(void *handle
);
568 static int ssh_do_close(Ssh ssh
, int notify_exit
);
569 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
570 static int ssh2_pkt_getbool(struct Packet
*pkt
);
571 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
572 static void ssh2_timer(void *ctx
, long now
);
573 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
574 struct Packet
*pktin
);
576 struct rdpkt1_state_tag
{
577 long len
, pad
, biglen
, to_read
;
578 unsigned long realcrc
, gotcrc
;
582 struct Packet
*pktin
;
585 struct rdpkt2_state_tag
{
586 long len
, pad
, payload
, packetlen
, maclen
;
589 unsigned long incoming_sequence
;
590 struct Packet
*pktin
;
593 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
594 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
596 struct queued_handler
;
597 struct queued_handler
{
599 chandler_fn_t handler
;
601 struct queued_handler
*next
;
605 const struct plug_function_table
*fn
;
606 /* the above field _must_ be first in the structure */
608 SHA_State exhash
, exhashbase
;
615 unsigned char session_key
[32];
617 int v1_remote_protoflags
;
618 int v1_local_protoflags
;
619 int agentfwd_enabled
;
622 const struct ssh_cipher
*cipher
;
625 const struct ssh2_cipher
*cscipher
, *sccipher
;
626 void *cs_cipher_ctx
, *sc_cipher_ctx
;
627 const struct ssh_mac
*csmac
, *scmac
;
628 void *cs_mac_ctx
, *sc_mac_ctx
;
629 const struct ssh_compress
*cscomp
, *sccomp
;
630 void *cs_comp_ctx
, *sc_comp_ctx
;
631 const struct ssh_kex
*kex
;
632 const struct ssh_signkey
*hostkey
;
633 unsigned char v2_session_id
[20];
639 int echoing
, editing
;
643 int ospeed
, ispeed
; /* temporaries */
644 int term_width
, term_height
;
646 tree234
*channels
; /* indexed by local id */
647 struct ssh_channel
*mainchan
; /* primary session channel */
651 tree234
*rportfwds
, *portfwds
;
655 SSH_STATE_BEFORE_SIZE
,
661 int size_needed
, eof_needed
;
663 struct Packet
**queue
;
664 int queuelen
, queuesize
;
666 unsigned char *deferred_send_data
;
667 int deferred_len
, deferred_size
;
670 * Gross hack: pscp will try to start SFTP but fall back to
671 * scp1 if that fails. This variable is the means by which
672 * scp.c can reach into the SSH code and find out which one it
678 * Used for username and password input.
680 char *userpass_input_buffer
;
681 int userpass_input_buflen
;
682 int userpass_input_bufpos
;
683 int userpass_input_echo
;
690 int v1_throttle_count
;
693 int v1_stdout_throttling
;
694 unsigned long v2_outgoing_sequence
;
696 int ssh1_rdpkt_crstate
;
697 int ssh2_rdpkt_crstate
;
698 int do_ssh_init_crstate
;
699 int ssh_gotdata_crstate
;
700 int do_ssh1_login_crstate
;
701 int do_ssh1_connection_crstate
;
702 int do_ssh2_transport_crstate
;
703 int do_ssh2_authconn_crstate
;
705 void *do_ssh_init_state
;
706 void *do_ssh1_login_state
;
707 void *do_ssh2_transport_state
;
708 void *do_ssh2_authconn_state
;
710 struct rdpkt1_state_tag rdpkt1_state
;
711 struct rdpkt2_state_tag rdpkt2_state
;
713 /* ssh1 and ssh2 use this for different things, but both use it */
714 int protocol_initial_phase_done
;
716 void (*protocol
) (Ssh ssh
, void *vin
, int inlen
,
718 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
721 * We maintain a full _copy_ of a Config structure here, not
722 * merely a pointer to it. That way, when we're passed a new
723 * one for reconfiguration, we can check the differences and
724 * potentially reconfigure port forwardings etc in mid-session.
729 * Used to transfer data back from async callbacks.
731 void *agent_response
;
732 int agent_response_len
;
736 * The SSH connection can be set as `frozen', meaning we are
737 * not currently accepting incoming data from the network. This
738 * is slightly more serious than setting the _socket_ as
739 * frozen, because we may already have had data passed to us
740 * from the network which we need to delay processing until
741 * after the freeze is lifted, so we also need a bufchain to
745 bufchain queued_incoming_data
;
748 * Dispatch table for packet types that we may have to deal
751 handler_fn_t packet_dispatch
[256];
754 * Queues of one-off handler functions for success/failure
755 * indications from a request.
757 struct queued_handler
*qhead
, *qtail
;
760 * This module deals with sending keepalives.
765 * Track incoming and outgoing data sizes and time, for
768 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
769 unsigned long max_data_size
;
771 long next_rekey
, last_rekey
;
772 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
775 #define logevent(s) logevent(ssh->frontend, s)
777 /* logevent, only printf-formatted. */
778 static void logeventf(Ssh ssh
, const char *fmt
, ...)
784 buf
= dupvprintf(fmt
, ap
);
790 #define bombout(msg) \
792 char *text = dupprintf msg; \
793 ssh_do_close(ssh, FALSE); \
795 connection_fatal(ssh->frontend, "%s", text); \
799 /* Functions to leave bits out of the SSH packet log file. */
801 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
803 if (ssh
->cfg
.logomitpass
)
804 pkt
->logmode
= blanktype
;
807 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
809 if (ssh
->cfg
.logomitdata
)
810 pkt
->logmode
= blanktype
;
813 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
815 pkt
->logmode
= PKTLOG_EMIT
;
818 static int ssh_channelcmp(void *av
, void *bv
)
820 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
821 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
822 if (a
->localid
< b
->localid
)
824 if (a
->localid
> b
->localid
)
828 static int ssh_channelfind(void *av
, void *bv
)
830 unsigned *a
= (unsigned *) av
;
831 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
839 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
841 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
842 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
844 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
845 return i
< 0 ?
-1 : +1;
846 if (a
->dport
> b
->dport
)
848 if (a
->dport
< b
->dport
)
853 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
855 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
856 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
858 if (a
->sport
> b
->sport
)
860 if (a
->sport
< b
->sport
)
866 * Special form of strcmp which can cope with NULL inputs. NULL is
867 * defined to sort before even the empty string.
869 static int nullstrcmp(const char *a
, const char *b
)
871 if (a
== NULL
&& b
== NULL
)
880 static int ssh_portcmp(void *av
, void *bv
)
882 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
883 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
885 if (a
->type
> b
->type
)
887 if (a
->type
< b
->type
)
889 if (a
->addressfamily
> b
->addressfamily
)
891 if (a
->addressfamily
< b
->addressfamily
)
893 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
894 return i
< 0 ?
-1 : +1;
895 if (a
->sport
> b
->sport
)
897 if (a
->sport
< b
->sport
)
899 if (a
->type
!= 'D') {
900 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
901 return i
< 0 ?
-1 : +1;
902 if (a
->dport
> b
->dport
)
904 if (a
->dport
< b
->dport
)
910 static int alloc_channel_id(Ssh ssh
)
912 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
913 unsigned low
, high
, mid
;
915 struct ssh_channel
*c
;
918 * First-fit allocation of channel numbers: always pick the
919 * lowest unused one. To do this, binary-search using the
920 * counted B-tree to find the largest channel ID which is in a
921 * contiguous sequence from the beginning. (Precisely
922 * everything in that sequence must have ID equal to its tree
923 * index plus CHANNEL_NUMBER_OFFSET.)
925 tsize
= count234(ssh
->channels
);
929 while (high
- low
> 1) {
930 mid
= (high
+ low
) / 2;
931 c
= index234(ssh
->channels
, mid
);
932 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
933 low
= mid
; /* this one is fine */
935 high
= mid
; /* this one is past it */
938 * Now low points to either -1, or the tree index of the
939 * largest ID in the initial sequence.
942 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
943 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
945 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
948 static void c_write(Ssh ssh
, const char *buf
, int len
)
950 if ((flags
& FLAG_STDERR
)) {
952 for (i
= 0; i
< len
; i
++)
954 fputc(buf
[i
], stderr
);
957 from_backend(ssh
->frontend
, 1, buf
, len
);
960 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
963 for (i
= 0; i
< len
; i
++) {
965 c_write(ssh
, "\r\n", 2);
966 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
967 c_write(ssh
, buf
+ i
, 1);
971 static void c_write_str(Ssh ssh
, const char *buf
)
973 c_write(ssh
, buf
, strlen(buf
));
976 static void ssh_free_packet(struct Packet
*pkt
)
981 static struct Packet
*ssh_new_packet(void)
983 struct Packet
*pkt
= snew(struct Packet
);
987 pkt
->logmode
= PKTLOG_EMIT
;
995 * Collect incoming data in the incoming packet buffer.
996 * Decipher and verify the packet when it is completely read.
997 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
998 * Update the *data and *datalen variables.
999 * Return a Packet structure when a packet is completed.
1001 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1003 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
1005 crBegin(ssh
->ssh1_rdpkt_crstate
);
1007 st
->pktin
= ssh_new_packet();
1009 st
->pktin
->type
= 0;
1010 st
->pktin
->length
= 0;
1012 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
1013 while ((*datalen
) == 0)
1015 st
->len
= (st
->len
<< 8) + **data
;
1016 (*data
)++, (*datalen
)--;
1019 st
->pad
= 8 - (st
->len
% 8);
1020 st
->biglen
= st
->len
+ st
->pad
;
1021 st
->pktin
->length
= st
->len
- 5;
1023 if (st
->biglen
< 0) {
1024 bombout(("Extremely large packet length from server suggests"
1025 " data stream corruption"));
1026 ssh_free_packet(st
->pktin
);
1030 st
->pktin
->maxlen
= st
->biglen
;
1031 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1033 st
->to_read
= st
->biglen
;
1034 st
->p
= st
->pktin
->data
;
1035 while (st
->to_read
> 0) {
1036 st
->chunk
= st
->to_read
;
1037 while ((*datalen
) == 0)
1039 if (st
->chunk
> (*datalen
))
1040 st
->chunk
= (*datalen
);
1041 memcpy(st
->p
, *data
, st
->chunk
);
1043 *datalen
-= st
->chunk
;
1045 st
->to_read
-= st
->chunk
;
1048 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1049 st
->biglen
, NULL
)) {
1050 bombout(("Network attack (CRC compensation) detected!"));
1051 ssh_free_packet(st
->pktin
);
1056 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1058 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1059 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1060 if (st
->gotcrc
!= st
->realcrc
) {
1061 bombout(("Incorrect CRC received on packet"));
1062 ssh_free_packet(st
->pktin
);
1066 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1067 st
->pktin
->savedpos
= 0;
1069 if (ssh
->v1_compressing
) {
1070 unsigned char *decompblk
;
1072 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1073 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1074 &decompblk
, &decomplen
)) {
1075 bombout(("Zlib decompression encountered invalid data"));
1076 ssh_free_packet(st
->pktin
);
1080 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1081 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1082 st
->pktin
->data
= sresize(st
->pktin
->data
,
1083 st
->pktin
->maxlen
+ APIEXTRA
,
1085 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1088 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1090 st
->pktin
->length
= decomplen
- 1;
1093 st
->pktin
->type
= st
->pktin
->body
[-1];
1096 * Log incoming packet, possibly omitting sensitive fields.
1100 struct logblank_t blank
;
1101 if (ssh
->cfg
.logomitdata
) {
1102 int do_blank
= FALSE
, blank_prefix
= 0;
1103 /* "Session data" packets - omit the data field */
1104 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1105 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1106 do_blank
= TRUE
; blank_prefix
= 0;
1107 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1108 do_blank
= TRUE
; blank_prefix
= 4;
1111 blank
.offset
= blank_prefix
;
1112 blank
.len
= st
->pktin
->length
;
1113 blank
.type
= PKTLOG_OMIT
;
1117 log_packet(ssh
->logctx
,
1118 PKT_INCOMING
, st
->pktin
->type
,
1119 ssh1_pkt_type(st
->pktin
->type
),
1120 st
->pktin
->body
, st
->pktin
->length
,
1124 crFinish(st
->pktin
);
1127 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1129 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1131 crBegin(ssh
->ssh2_rdpkt_crstate
);
1133 st
->pktin
= ssh_new_packet();
1135 st
->pktin
->type
= 0;
1136 st
->pktin
->length
= 0;
1138 st
->cipherblk
= ssh
->sccipher
->blksize
;
1141 if (st
->cipherblk
< 8)
1144 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1147 * Acquire and decrypt the first block of the packet. This will
1148 * contain the length and padding details.
1150 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1151 while ((*datalen
) == 0)
1153 st
->pktin
->data
[st
->i
] = *(*data
)++;
1158 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1159 st
->pktin
->data
, st
->cipherblk
);
1162 * Now get the length and padding figures.
1164 st
->len
= GET_32BIT(st
->pktin
->data
);
1165 st
->pad
= st
->pktin
->data
[4];
1168 * _Completely_ silly lengths should be stomped on before they
1169 * do us any more damage.
1171 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1172 bombout(("Incoming packet was garbled on decryption"));
1173 ssh_free_packet(st
->pktin
);
1178 * This enables us to deduce the payload length.
1180 st
->payload
= st
->len
- st
->pad
- 1;
1182 st
->pktin
->length
= st
->payload
+ 5;
1185 * So now we can work out the total packet length.
1187 st
->packetlen
= st
->len
+ 4;
1188 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1191 * Allocate memory for the rest of the packet.
1193 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1194 st
->pktin
->data
= sresize(st
->pktin
->data
,
1195 st
->pktin
->maxlen
+ APIEXTRA
,
1199 * Read and decrypt the remainder of the packet.
1201 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1203 while ((*datalen
) == 0)
1205 st
->pktin
->data
[st
->i
] = *(*data
)++;
1208 /* Decrypt everything _except_ the MAC. */
1210 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1211 st
->pktin
->data
+ st
->cipherblk
,
1212 st
->packetlen
- st
->cipherblk
);
1214 st
->pktin
->encrypted_len
= st
->packetlen
;
1220 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1221 st
->incoming_sequence
)) {
1222 bombout(("Incorrect MAC received on packet"));
1223 ssh_free_packet(st
->pktin
);
1227 st
->pktin
->sequence
= st
->incoming_sequence
++;
1230 * Decompress packet payload.
1233 unsigned char *newpayload
;
1236 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1237 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1238 &newpayload
, &newlen
)) {
1239 if (st
->pktin
->maxlen
< newlen
+ 5) {
1240 st
->pktin
->maxlen
= newlen
+ 5;
1241 st
->pktin
->data
= sresize(st
->pktin
->data
,
1242 st
->pktin
->maxlen
+ APIEXTRA
,
1245 st
->pktin
->length
= 5 + newlen
;
1246 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1251 st
->pktin
->savedpos
= 6;
1252 st
->pktin
->body
= st
->pktin
->data
;
1253 st
->pktin
->type
= st
->pktin
->data
[5];
1256 * Log incoming packet, possibly omitting sensitive fields.
1260 struct logblank_t blank
;
1261 if (ssh
->cfg
.logomitdata
) {
1262 int do_blank
= FALSE
, blank_prefix
= 0;
1263 /* "Session data" packets - omit the data field */
1264 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1265 do_blank
= TRUE
; blank_prefix
= 4;
1266 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1267 do_blank
= TRUE
; blank_prefix
= 8;
1270 blank
.offset
= blank_prefix
;
1271 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1272 blank
.type
= PKTLOG_OMIT
;
1276 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1277 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1278 st
->pktin
->data
+6, st
->pktin
->length
-6,
1282 crFinish(st
->pktin
);
1285 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1289 len
+= 5; /* type and CRC */
1290 pad
= 8 - (len
% 8);
1293 pkt
->length
= len
- 5;
1294 if (pkt
->maxlen
< biglen
) {
1295 pkt
->maxlen
= biglen
;
1296 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1298 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1301 static struct Packet
*s_wrpkt_start(int type
, int len
)
1303 struct Packet
*pkt
= ssh_new_packet();
1304 ssh1_pktout_size(pkt
, len
);
1306 /* Initialise log omission state */
1312 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1318 * XXX various versions of SC (including 8.8.4) screw up the
1319 * register allocation in this function and use the same register
1320 * (D6) for len and as a temporary, with predictable results. The
1321 * following sledgehammer prevents this.
1327 pkt
->body
[-1] = pkt
->type
;
1330 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1331 ssh1_pkt_type(pkt
->type
),
1332 pkt
->body
, pkt
->length
,
1333 pkt
->nblanks
, pkt
->blanks
);
1334 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1337 if (ssh
->v1_compressing
) {
1338 unsigned char *compblk
;
1340 zlib_compress_block(ssh
->cs_comp_ctx
,
1341 pkt
->body
- 1, pkt
->length
+ 1,
1342 &compblk
, &complen
);
1343 ssh1_pktout_size(pkt
, complen
- 1);
1344 memcpy(pkt
->body
- 1, compblk
, complen
);
1348 len
= pkt
->length
+ 5; /* type and CRC */
1349 pad
= 8 - (len
% 8);
1352 for (i
= 0; i
< pad
; i
++)
1353 pkt
->data
[i
+ 4] = random_byte();
1354 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1355 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1356 PUT_32BIT(pkt
->data
, len
);
1359 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1364 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1367 len
= s_wrpkt_prepare(ssh
, pkt
);
1368 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1369 if (backlog
> SSH_MAX_BACKLOG
)
1370 ssh_throttle_all(ssh
, 1, backlog
);
1373 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1376 len
= s_wrpkt_prepare(ssh
, pkt
);
1377 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1378 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1379 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1383 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1384 ssh
->deferred_len
+= len
;
1388 * Construct a packet with the specified contents.
1390 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1391 va_list ap1
, va_list ap2
)
1393 unsigned char *p
, *argp
, argchar
;
1394 unsigned long argint
;
1395 int pktlen
, argtype
, arglen
;
1400 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1403 (void) va_arg(ap1
, int);
1407 (void) va_arg(ap1
, int);
1411 (void) va_arg(ap1
, unsigned char *);
1412 arglen
= va_arg(ap1
, int);
1416 argp
= va_arg(ap1
, unsigned char *);
1417 arglen
= strlen((char *)argp
);
1418 pktlen
+= 4 + arglen
;
1421 bn
= va_arg(ap1
, Bignum
);
1422 pktlen
+= ssh1_bignum_length(bn
);
1427 /* ignore this pass */
1434 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1437 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1438 int offset
= p
- pkt
->body
, len
= 0;
1440 /* Actual fields in the packet */
1442 argint
= va_arg(ap2
, int);
1443 PUT_32BIT(p
, argint
);
1447 argchar
= (unsigned char) va_arg(ap2
, int);
1452 argp
= va_arg(ap2
, unsigned char *);
1453 arglen
= va_arg(ap2
, int);
1454 memcpy(p
, argp
, arglen
);
1458 argp
= va_arg(ap2
, unsigned char *);
1459 arglen
= strlen((char *)argp
);
1460 PUT_32BIT(p
, arglen
);
1461 memcpy(p
+ 4, argp
, arglen
);
1465 bn
= va_arg(ap2
, Bignum
);
1466 len
= ssh1_write_bignum(p
, bn
);
1468 /* Tokens for modifications to packet logging */
1470 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1473 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1476 end_log_omission(ssh
, pkt
);
1480 /* Deal with logfile omission, if required. */
1481 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1483 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1485 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1486 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1487 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1494 static void send_packet(Ssh ssh
, int pkttype
, ...)
1498 va_start(ap1
, pkttype
);
1499 va_start(ap2
, pkttype
);
1500 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1504 ssh_free_packet(pkt
);
1507 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1511 va_start(ap1
, pkttype
);
1512 va_start(ap2
, pkttype
);
1513 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1516 s_wrpkt_defer(ssh
, pkt
);
1517 ssh_free_packet(pkt
);
1520 static int ssh_versioncmp(char *a
, char *b
)
1523 unsigned long av
, bv
;
1525 av
= strtoul(a
, &ae
, 10);
1526 bv
= strtoul(b
, &be
, 10);
1528 return (av
< bv ?
-1 : +1);
1533 av
= strtoul(ae
, &ae
, 10);
1534 bv
= strtoul(be
, &be
, 10);
1536 return (av
< bv ?
-1 : +1);
1541 * Utility routines for putting an SSH-protocol `string' and
1542 * `uint32' into a SHA state.
1545 static void sha_string(SHA_State
* s
, void *str
, int len
)
1547 unsigned char lenblk
[4];
1548 PUT_32BIT(lenblk
, len
);
1549 SHA_Bytes(s
, lenblk
, 4);
1550 SHA_Bytes(s
, str
, len
);
1553 static void sha_uint32(SHA_State
* s
, unsigned i
)
1555 unsigned char intblk
[4];
1556 PUT_32BIT(intblk
, i
);
1557 SHA_Bytes(s
, intblk
, 4);
1561 * SSH2 packet construction functions.
1563 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1565 if (pkt
->maxlen
< length
) {
1566 pkt
->maxlen
= length
+ 256;
1567 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1570 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1572 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1574 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1575 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1576 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1577 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1580 ssh2_pkt_ensure(pkt
, pkt
->length
);
1581 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1583 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1585 ssh2_pkt_adddata(pkt
, &byte
, 1);
1587 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1589 struct Packet
*pkt
= ssh_new_packet();
1592 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1595 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1597 ssh2_pkt_adddata(pkt
, &value
, 1);
1599 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1602 PUT_32BIT(x
, value
);
1603 ssh2_pkt_adddata(pkt
, x
, 4);
1605 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1607 ssh2_pkt_adduint32(pkt
, 0);
1608 pkt
->savedpos
= pkt
->length
;
1610 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1612 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1613 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1615 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1617 ssh2_pkt_adddata(pkt
, data
, len
);
1618 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1620 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1622 ssh2_pkt_addstring_start(pkt
);
1623 ssh2_pkt_addstring_str(pkt
, data
);
1625 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1628 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1629 p
= snewn(n
+ 1, unsigned char);
1631 fatalbox("out of memory");
1633 for (i
= 1; i
<= n
; i
++)
1634 p
[i
] = bignum_byte(b
, n
- i
);
1636 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1638 memmove(p
, p
+ i
, n
+ 1 - i
);
1642 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1646 p
= ssh2_mpint_fmt(b
, &len
);
1647 ssh2_pkt_addstring_start(pkt
);
1648 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1653 * Construct an SSH2 final-form packet: compress it, encrypt it,
1654 * put the MAC on it. Final packet, ready to be sent, is stored in
1655 * pkt->data. Total length is returned.
1657 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1659 int cipherblk
, maclen
, padding
, i
;
1662 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1663 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1664 pkt
->data
+ 6, pkt
->length
- 6,
1665 pkt
->nblanks
, pkt
->blanks
);
1666 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1670 * Compress packet payload.
1673 unsigned char *newpayload
;
1676 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1678 &newpayload
, &newlen
)) {
1680 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1686 * Add padding. At least four bytes, and must also bring total
1687 * length (minus MAC) up to a multiple of the block size.
1688 * If pkt->forcepad is set, make sure the packet is at least that size
1691 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1692 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1694 if (pkt
->length
+ padding
< pkt
->forcepad
)
1695 padding
= pkt
->forcepad
- pkt
->length
;
1697 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1698 assert(padding
<= 255);
1699 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1700 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1701 pkt
->data
[4] = padding
;
1702 for (i
= 0; i
< padding
; i
++)
1703 pkt
->data
[pkt
->length
+ i
] = random_byte();
1704 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1706 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1707 pkt
->length
+ padding
,
1708 ssh
->v2_outgoing_sequence
);
1709 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1712 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1713 pkt
->data
, pkt
->length
+ padding
);
1715 pkt
->encrypted_len
= pkt
->length
+ padding
;
1717 /* Ready-to-send packet starts at pkt->data. We return length. */
1718 return pkt
->length
+ padding
+ maclen
;
1722 * Routines called from the main SSH code to send packets. There
1723 * are quite a few of these, because we have two separate
1724 * mechanisms for delaying the sending of packets:
1726 * - In order to send an IGNORE message and a password message in
1727 * a single fixed-length blob, we require the ability to
1728 * concatenate the encrypted forms of those two packets _into_ a
1729 * single blob and then pass it to our <network.h> transport
1730 * layer in one go. Hence, there's a deferment mechanism which
1731 * works after packet encryption.
1733 * - In order to avoid sending any connection-layer messages
1734 * during repeat key exchange, we have to queue up any such
1735 * outgoing messages _before_ they are encrypted (and in
1736 * particular before they're allocated sequence numbers), and
1737 * then send them once we've finished.
1739 * I call these mechanisms `defer' and `queue' respectively, so as
1740 * to distinguish them reasonably easily.
1742 * The functions send_noqueue() and defer_noqueue() free the packet
1743 * structure they are passed. Every outgoing packet goes through
1744 * precisely one of these functions in its life; packets passed to
1745 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1746 * these or get queued, and then when the queue is later emptied
1747 * the packets are all passed to defer_noqueue().
1751 * Send an SSH2 packet immediately, without queuing or deferring.
1753 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1757 len
= ssh2_pkt_construct(ssh
, pkt
);
1758 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1759 if (backlog
> SSH_MAX_BACKLOG
)
1760 ssh_throttle_all(ssh
, 1, backlog
);
1762 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1763 if (!ssh
->kex_in_progress
&&
1764 ssh
->max_data_size
!= 0 &&
1765 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1766 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1768 ssh_free_packet(pkt
);
1772 * Defer an SSH2 packet.
1774 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1776 int len
= ssh2_pkt_construct(ssh
, pkt
);
1777 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1778 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1779 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1783 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1784 ssh
->deferred_len
+= len
;
1785 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1786 ssh_free_packet(pkt
);
1790 * Queue an SSH2 packet.
1792 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1794 assert(ssh
->queueing
);
1796 if (ssh
->queuelen
>= ssh
->queuesize
) {
1797 ssh
->queuesize
= ssh
->queuelen
+ 32;
1798 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1801 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1805 * Either queue or send a packet, depending on whether queueing is
1808 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1811 ssh2_pkt_queue(ssh
, pkt
);
1813 ssh2_pkt_send_noqueue(ssh
, pkt
);
1818 * Either queue or defer a packet, depending on whether queueing is
1821 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1824 ssh2_pkt_queue(ssh
, pkt
);
1826 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1831 * Send the whole deferred data block constructed by
1832 * ssh2_pkt_defer() or SSH1's defer_packet().
1834 * The expected use of the defer mechanism is that you call
1835 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1836 * not currently queueing, this simply sets up deferred_send_data
1837 * and then sends it. If we _are_ currently queueing, the calls to
1838 * ssh2_pkt_defer() put the deferred packets on to the queue
1839 * instead, and therefore ssh_pkt_defersend() has no deferred data
1840 * to send. Hence, there's no need to make it conditional on
1843 static void ssh_pkt_defersend(Ssh ssh
)
1846 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1848 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1849 sfree(ssh
->deferred_send_data
);
1850 ssh
->deferred_send_data
= NULL
;
1851 if (backlog
> SSH_MAX_BACKLOG
)
1852 ssh_throttle_all(ssh
, 1, backlog
);
1854 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1855 if (!ssh
->kex_in_progress
&&
1856 ssh
->max_data_size
!= 0 &&
1857 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1858 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1859 ssh
->deferred_data_size
= 0;
1863 * Send all queued SSH2 packets. We send them by means of
1864 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1865 * packets that needed to be lumped together.
1867 static void ssh2_pkt_queuesend(Ssh ssh
)
1871 assert(!ssh
->queueing
);
1873 for (i
= 0; i
< ssh
->queuelen
; i
++)
1874 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1877 ssh_pkt_defersend(ssh
);
1881 void bndebug(char *string
, Bignum b
)
1885 p
= ssh2_mpint_fmt(b
, &len
);
1886 debug(("%s", string
));
1887 for (i
= 0; i
< len
; i
++)
1888 debug((" %02x", p
[i
]));
1894 static void sha_mpint(SHA_State
* s
, Bignum b
)
1898 p
= ssh2_mpint_fmt(b
, &len
);
1899 sha_string(s
, p
, len
);
1904 * Packet decode functions for both SSH1 and SSH2.
1906 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1908 unsigned long value
;
1909 if (pkt
->length
- pkt
->savedpos
< 4)
1910 return 0; /* arrgh, no way to decline (FIXME?) */
1911 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1915 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1917 unsigned long value
;
1918 if (pkt
->length
- pkt
->savedpos
< 1)
1919 return 0; /* arrgh, no way to decline (FIXME?) */
1920 value
= pkt
->body
[pkt
->savedpos
] != 0;
1924 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1929 if (pkt
->length
- pkt
->savedpos
< 4)
1931 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1936 if (pkt
->length
- pkt
->savedpos
< *length
)
1938 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1939 pkt
->savedpos
+= *length
;
1941 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1943 if (pkt
->length
- pkt
->savedpos
< length
)
1945 pkt
->savedpos
+= length
;
1946 return pkt
->body
+ (pkt
->savedpos
- length
);
1948 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1949 unsigned char **keystr
)
1953 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1954 pkt
->length
- pkt
->savedpos
,
1961 assert(pkt
->savedpos
< pkt
->length
);
1965 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1970 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1971 pkt
->length
- pkt
->savedpos
, &b
);
1979 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1985 ssh_pkt_getstring(pkt
, &p
, &length
);
1990 b
= bignum_from_bytes((unsigned char *)p
, length
);
1995 * Helper function to add an SSH2 signature blob to a packet.
1996 * Expects to be shown the public key blob as well as the signature
1997 * blob. Normally works just like ssh2_pkt_addstring, but will
1998 * fiddle with the signature packet if necessary for
1999 * BUG_SSH2_RSA_PADDING.
2001 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
2002 void *pkblob_v
, int pkblob_len
,
2003 void *sigblob_v
, int sigblob_len
)
2005 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
2006 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
2008 /* dmemdump(pkblob, pkblob_len); */
2009 /* dmemdump(sigblob, sigblob_len); */
2012 * See if this is in fact an ssh-rsa signature and a buggy
2013 * server; otherwise we can just do this the easy way.
2015 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
2016 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
2017 int pos
, len
, siglen
;
2020 * Find the byte length of the modulus.
2023 pos
= 4+7; /* skip over "ssh-rsa" */
2024 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
2025 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2026 pos
+= 4; /* find modulus itself */
2027 while (len
> 0 && pkblob
[pos
] == 0)
2029 /* debug(("modulus length is %d\n", len)); */
2032 * Now find the signature integer.
2034 pos
= 4+7; /* skip over "ssh-rsa" */
2035 siglen
= GET_32BIT(sigblob
+pos
);
2036 /* debug(("signature length is %d\n", siglen)); */
2038 if (len
!= siglen
) {
2039 unsigned char newlen
[4];
2040 ssh2_pkt_addstring_start(pkt
);
2041 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2042 /* dmemdump(sigblob, pos); */
2043 pos
+= 4; /* point to start of actual sig */
2044 PUT_32BIT(newlen
, len
);
2045 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2046 /* dmemdump(newlen, 4); */
2048 while (len
-- > siglen
) {
2049 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2050 /* dmemdump(newlen, 1); */
2052 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2053 /* dmemdump(sigblob+pos, siglen); */
2057 /* Otherwise fall through and do it the easy way. */
2060 ssh2_pkt_addstring_start(pkt
);
2061 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2065 * Examine the remote side's version string and compare it against
2066 * a list of known buggy implementations.
2068 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2070 char *imp
; /* pointer to implementation part */
2072 imp
+= strcspn(imp
, "-");
2074 imp
+= strcspn(imp
, "-");
2077 ssh
->remote_bugs
= 0;
2079 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2080 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2081 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2082 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2083 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2084 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2086 * These versions don't support SSH1_MSG_IGNORE, so we have
2087 * to use a different defence against password length
2090 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2091 logevent("We believe remote version has SSH1 ignore bug");
2094 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2095 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2096 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2098 * These versions need a plain password sent; they can't
2099 * handle having a null and a random length of data after
2102 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2103 logevent("We believe remote version needs a plain SSH1 password");
2106 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2107 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2108 (!strcmp(imp
, "Cisco-1.25")))) {
2110 * These versions apparently have no clue whatever about
2111 * RSA authentication and will panic and die if they see
2112 * an AUTH_RSA message.
2114 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2115 logevent("We believe remote version can't handle RSA authentication");
2118 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2119 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2120 !wc_match("* VShell", imp
) &&
2121 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2122 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2123 wc_match("2.1 *", imp
)))) {
2125 * These versions have the HMAC bug.
2127 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2128 logevent("We believe remote version has SSH2 HMAC bug");
2131 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2132 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2133 !wc_match("* VShell", imp
) &&
2134 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2136 * These versions have the key-derivation bug (failing to
2137 * include the literal shared secret in the hashes that
2138 * generate the keys).
2140 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2141 logevent("We believe remote version has SSH2 key-derivation bug");
2144 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2145 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2146 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2147 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2149 * These versions have the SSH2 RSA padding bug.
2151 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2152 logevent("We believe remote version has SSH2 RSA padding bug");
2155 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2156 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2157 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2159 * These versions have the SSH2 session-ID bug in
2160 * public-key authentication.
2162 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2163 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2166 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2167 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2168 (wc_match("OpenSSH_2.[0-4]*", imp
) ||
2169 wc_match("OpenSSH_2.5.[0-3]*", imp
) ||
2170 wc_match("Sun_SSH_1.0", imp
) ||
2171 wc_match("Sun_SSH_1.0.1", imp
)))) {
2173 * These versions have the SSH2 rekey bug.
2175 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2176 logevent("We believe remote version has SSH2 rekey bug");
2181 * The `software version' part of an SSH version string is required
2182 * to contain no spaces or minus signs.
2184 static void ssh_fix_verstring(char *str
)
2186 /* Eat "SSH-<protoversion>-". */
2187 assert(*str
== 'S'); str
++;
2188 assert(*str
== 'S'); str
++;
2189 assert(*str
== 'H'); str
++;
2190 assert(*str
== '-'); str
++;
2191 while (*str
&& *str
!= '-') str
++;
2192 assert(*str
== '-'); str
++;
2194 /* Convert minus signs and spaces in the remaining string into
2197 if (*str
== '-' || *str
== ' ')
2203 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2205 struct do_ssh_init_state
{
2213 crState(do_ssh_init_state
);
2215 crBegin(ssh
->do_ssh_init_crstate
);
2217 /* Search for the string "SSH-" in the input. */
2220 static const int transS
[] = { 1, 2, 2, 1 };
2221 static const int transH
[] = { 0, 0, 3, 0 };
2222 static const int transminus
[] = { 0, 0, 0, -1 };
2224 s
->i
= transS
[s
->i
];
2226 s
->i
= transH
[s
->i
];
2228 s
->i
= transminus
[s
->i
];
2233 crReturn(1); /* get another character */
2237 s
->vstring
= snewn(s
->vstrsize
, char);
2238 strcpy(s
->vstring
, "SSH-");
2242 crReturn(1); /* get another char */
2243 if (s
->vslen
>= s
->vstrsize
- 1) {
2245 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2247 s
->vstring
[s
->vslen
++] = c
;
2250 s
->version
[s
->i
] = '\0';
2252 } else if (s
->i
< sizeof(s
->version
) - 1)
2253 s
->version
[s
->i
++] = c
;
2254 } else if (c
== '\012')
2258 ssh
->agentfwd_enabled
= FALSE
;
2259 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2261 s
->vstring
[s
->vslen
] = 0;
2262 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2263 logeventf(ssh
, "Server version: %s", s
->vstring
);
2264 ssh_detect_bugs(ssh
, s
->vstring
);
2267 * Decide which SSH protocol version to support.
2270 /* Anything strictly below "2.0" means protocol 1 is supported. */
2271 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2272 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2273 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2275 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2276 bombout(("SSH protocol version 1 required by user but not provided by server"));
2279 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2280 bombout(("SSH protocol version 2 required by user but not provided by server"));
2287 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2289 * Construct a v2 version string.
2291 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2295 * Construct a v1 version string.
2297 verstring
= dupprintf("SSH-%s-%s\012",
2298 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2299 s
->version
: "1.5"),
2304 ssh_fix_verstring(verstring
);
2306 if (ssh
->version
== 2) {
2308 * Hash our version string and their version string.
2310 SHA_Init(&ssh
->exhashbase
);
2311 sha_string(&ssh
->exhashbase
, verstring
,
2312 strcspn(verstring
, "\015\012"));
2313 sha_string(&ssh
->exhashbase
, s
->vstring
,
2314 strcspn(s
->vstring
, "\015\012"));
2317 * Initialise SSHv2 protocol.
2319 ssh
->protocol
= ssh2_protocol
;
2320 ssh2_protocol_setup(ssh
);
2321 ssh
->s_rdpkt
= ssh2_rdpkt
;
2324 * Initialise SSHv1 protocol.
2326 ssh
->protocol
= ssh1_protocol
;
2327 ssh1_protocol_setup(ssh
);
2328 ssh
->s_rdpkt
= ssh1_rdpkt
;
2330 logeventf(ssh
, "We claim version: %.*s",
2331 strcspn(verstring
, "\015\012"), verstring
);
2332 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2336 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2338 update_specials_menu(ssh
->frontend
);
2339 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2340 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2347 static void ssh_process_incoming_data(Ssh ssh
,
2348 unsigned char **data
, int *datalen
)
2350 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, data
, datalen
);
2352 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2353 ssh_free_packet(pktin
);
2357 static void ssh_queue_incoming_data(Ssh ssh
,
2358 unsigned char **data
, int *datalen
)
2360 bufchain_add(&ssh
->queued_incoming_data
, *data
, *datalen
);
2365 static void ssh_process_queued_incoming_data(Ssh ssh
)
2368 unsigned char *data
;
2371 while (!ssh
->frozen
&& bufchain_size(&ssh
->queued_incoming_data
)) {
2372 bufchain_prefix(&ssh
->queued_incoming_data
, &vdata
, &len
);
2376 while (!ssh
->frozen
&& len
> 0)
2377 ssh_process_incoming_data(ssh
, &data
, &len
);
2380 bufchain_consume(&ssh
->queued_incoming_data
, origlen
- len
);
2384 static void ssh_set_frozen(Ssh ssh
, int frozen
)
2387 sk_set_frozen(ssh
->s
, frozen
);
2388 ssh
->frozen
= frozen
;
2391 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2393 crBegin(ssh
->ssh_gotdata_crstate
);
2396 * To begin with, feed the characters one by one to the
2397 * protocol initialisation / selection function do_ssh_init().
2398 * When that returns 0, we're done with the initial greeting
2399 * exchange and can move on to packet discipline.
2402 int ret
; /* need not be kept across crReturn */
2404 crReturnV
; /* more data please */
2405 ret
= do_ssh_init(ssh
, *data
);
2413 * We emerge from that loop when the initial negotiation is
2414 * over and we have selected an s_rdpkt function. Now pass
2415 * everything to s_rdpkt, and then pass the resulting packets
2416 * to the proper protocol handler.
2422 * Process queued data if there is any.
2424 ssh_process_queued_incoming_data(ssh
);
2427 while (datalen
> 0) {
2429 ssh_queue_incoming_data(ssh
, &data
, &datalen
);
2431 ssh_process_incoming_data(ssh
, &data
, &datalen
);
2433 if (ssh
->state
== SSH_STATE_CLOSED
)
2441 static int ssh_do_close(Ssh ssh
, int notify_exit
)
2444 struct ssh_channel
*c
;
2446 ssh
->state
= SSH_STATE_CLOSED
;
2451 notify_remote_exit(ssh
->frontend
);
2456 * Now we must shut down any port- and X-forwarded channels going
2457 * through this connection.
2459 if (ssh
->channels
) {
2460 while (NULL
!= (c
= index234(ssh
->channels
, 0))) {
2463 x11_close(c
->u
.x11
.s
);
2466 pfd_close(c
->u
.pfd
.s
);
2469 del234(ssh
->channels
, c
); /* moving next one to index 0 */
2470 if (ssh
->version
== 2)
2471 bufchain_clear(&c
->v
.v2
.outbuffer
);
2476 * Go through port-forwardings, and close any associated
2477 * listening sockets.
2479 if (ssh
->portfwds
) {
2480 struct ssh_portfwd
*pf
;
2481 while (NULL
!= (pf
= index234(ssh
->portfwds
, 0))) {
2482 /* Dispose of any listening socket. */
2484 pfd_terminate(pf
->local
);
2485 del234(ssh
->portfwds
, pf
); /* moving next one to index 0 */
2493 static void ssh_log(Plug plug
, int type
, SockAddr addr
, int port
,
2494 const char *error_msg
, int error_code
)
2496 Ssh ssh
= (Ssh
) plug
;
2497 char addrbuf
[256], *msg
;
2499 sk_getaddr(addr
, addrbuf
, lenof(addrbuf
));
2502 msg
= dupprintf("Connecting to %s port %d", addrbuf
, port
);
2504 msg
= dupprintf("Failed to connect to %s: %s", addrbuf
, error_msg
);
2510 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2513 Ssh ssh
= (Ssh
) plug
;
2514 int need_notify
= ssh_do_close(ssh
, FALSE
);
2516 if (!error_msg
&& !ssh
->close_expected
) {
2517 error_msg
= "Server unexpectedly closed network connection";
2521 notify_remote_exit(ssh
->frontend
);
2524 /* A socket error has occurred. */
2525 logevent(error_msg
);
2526 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2528 logevent("Server closed network connection");
2533 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2535 Ssh ssh
= (Ssh
) plug
;
2536 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2537 if (ssh
->state
== SSH_STATE_CLOSED
) {
2538 ssh_do_close(ssh
, TRUE
);
2544 static void ssh_sent(Plug plug
, int bufsize
)
2546 Ssh ssh
= (Ssh
) plug
;
2548 * If the send backlog on the SSH socket itself clears, we
2549 * should unthrottle the whole world if it was throttled.
2551 if (bufsize
< SSH_MAX_BACKLOG
)
2552 ssh_throttle_all(ssh
, 0, bufsize
);
2556 * Connect to specified host and port.
2557 * Returns an error message, or NULL on success.
2558 * Also places the canonical host name into `realhost'. It must be
2559 * freed by the caller.
2561 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2562 char **realhost
, int nodelay
, int keepalive
)
2564 static const struct plug_function_table fn_table
= {
2575 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2576 if (!ssh
->savedhost
)
2577 fatalbox("Out of memory");
2578 strcpy(ssh
->savedhost
, host
);
2581 port
= 22; /* default ssh port */
2582 ssh
->savedport
= port
;
2587 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2588 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2589 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2590 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2591 ssh
->cfg
.addressfamily
);
2592 if ((err
= sk_addr_error(addr
)) != NULL
) {
2600 ssh
->fn
= &fn_table
;
2601 ssh
->s
= new_connection(addr
, *realhost
, port
,
2602 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2603 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2605 notify_remote_exit(ssh
->frontend
);
2613 * Throttle or unthrottle the SSH connection.
2615 static void ssh1_throttle(Ssh ssh
, int adjust
)
2617 int old_count
= ssh
->v1_throttle_count
;
2618 ssh
->v1_throttle_count
+= adjust
;
2619 assert(ssh
->v1_throttle_count
>= 0);
2620 if (ssh
->v1_throttle_count
&& !old_count
) {
2621 ssh_set_frozen(ssh
, 1);
2622 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2623 ssh_set_frozen(ssh
, 0);
2628 * Throttle or unthrottle _all_ local data streams (for when sends
2629 * on the SSH connection itself back up).
2631 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2634 struct ssh_channel
*c
;
2636 if (enable
== ssh
->throttled_all
)
2638 ssh
->throttled_all
= enable
;
2639 ssh
->overall_bufsize
= bufsize
;
2642 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2644 case CHAN_MAINSESSION
:
2646 * This is treated separately, outside the switch.
2650 x11_override_throttle(c
->u
.x11
.s
, enable
);
2653 /* Agent channels require no buffer management. */
2656 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2663 * Username and password input, abstracted off into routines
2664 * reusable in several places - even between SSH1 and SSH2.
2667 /* Set up a username or password input loop on a given buffer. */
2668 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2670 ssh
->userpass_input_buffer
= buffer
;
2671 ssh
->userpass_input_buflen
= buflen
;
2672 ssh
->userpass_input_bufpos
= 0;
2673 ssh
->userpass_input_echo
= echo
;
2677 * Process some terminal data in the course of username/password
2678 * input. Returns >0 for success (line of input returned in
2679 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2680 * for inconclusive (keep waiting for more input please).
2682 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2687 switch (c
= *in
++) {
2690 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2691 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2696 if (ssh
->userpass_input_bufpos
> 0) {
2697 if (ssh
->userpass_input_echo
)
2698 c_write_str(ssh
, "\b \b");
2699 ssh
->userpass_input_bufpos
--;
2704 while (ssh
->userpass_input_bufpos
> 0) {
2705 if (ssh
->userpass_input_echo
)
2706 c_write_str(ssh
, "\b \b");
2707 ssh
->userpass_input_bufpos
--;
2716 * This simplistic check for printability is disabled
2717 * when we're doing password input, because some people
2718 * have control characters in their passwords.o
2720 if ((!ssh
->userpass_input_echo
||
2721 (c
>= ' ' && c
<= '~') ||
2722 ((unsigned char) c
>= 160))
2723 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2724 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2725 if (ssh
->userpass_input_echo
)
2726 c_write(ssh
, &c
, 1);
2734 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2736 Ssh ssh
= (Ssh
) sshv
;
2738 ssh
->agent_response
= reply
;
2739 ssh
->agent_response_len
= replylen
;
2741 if (ssh
->version
== 1)
2742 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2744 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2747 static void ssh_dialog_callback(void *sshv
, int ret
)
2749 Ssh ssh
= (Ssh
) sshv
;
2751 ssh
->user_response
= ret
;
2753 if (ssh
->version
== 1)
2754 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2756 do_ssh2_transport(ssh
, NULL
, -1, NULL
);
2759 * This may have unfrozen the SSH connection, so do a
2762 ssh_process_queued_incoming_data(ssh
);
2765 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2767 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2769 void *sentreply
= reply
;
2772 /* Fake SSH_AGENT_FAILURE. */
2773 sentreply
= "\0\0\0\1\5";
2776 if (ssh
->version
== 2) {
2777 ssh2_add_channel_data(c
, sentreply
, replylen
);
2780 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2781 PKT_INT
, c
->remoteid
,
2784 PKT_DATA
, sentreply
, replylen
,
2793 * Handle the key exchange and user authentication phases.
2795 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2796 struct Packet
*pktin
)
2799 unsigned char cookie
[8], *ptr
;
2800 struct RSAKey servkey
, hostkey
;
2801 struct MD5Context md5c
;
2802 struct do_ssh1_login_state
{
2804 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2805 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2806 int tried_publickey
, tried_agent
;
2807 int tis_auth_refused
, ccard_auth_refused
;
2808 unsigned char session_id
[16];
2811 void *publickey_blob
;
2812 int publickey_bloblen
;
2818 unsigned char request
[5], *response
, *p
;
2828 crState(do_ssh1_login_state
);
2830 crBegin(ssh
->do_ssh1_login_crstate
);
2835 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2836 bombout(("Public key packet not received"));
2840 logevent("Received public keys");
2842 ptr
= ssh_pkt_getdata(pktin
, 8);
2844 bombout(("SSH1 public key packet stopped before random cookie"));
2847 memcpy(cookie
, ptr
, 8);
2849 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2850 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2851 bombout(("Failed to read SSH1 public keys from public key packet"));
2856 * Log the host key fingerprint.
2860 logevent("Host key fingerprint is:");
2861 strcpy(logmsg
, " ");
2862 hostkey
.comment
= NULL
;
2863 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2864 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2868 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2869 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2870 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2872 ssh
->v1_local_protoflags
=
2873 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2874 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2877 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2878 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2879 MD5Update(&md5c
, cookie
, 8);
2880 MD5Final(s
->session_id
, &md5c
);
2882 for (i
= 0; i
< 32; i
++)
2883 ssh
->session_key
[i
] = random_byte();
2886 * Verify that the `bits' and `bytes' parameters match.
2888 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2889 servkey
.bits
> servkey
.bytes
* 8) {
2890 bombout(("SSH1 public keys were badly formatted"));
2894 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2896 s
->rsabuf
= snewn(s
->len
, unsigned char);
2898 fatalbox("Out of memory");
2901 * Verify the host key.
2905 * First format the key into a string.
2907 int len
= rsastr_len(&hostkey
);
2908 char fingerprint
[100];
2909 char *keystr
= snewn(len
, char);
2911 fatalbox("Out of memory");
2912 rsastr_fmt(keystr
, &hostkey
);
2913 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2915 ssh_set_frozen(ssh
, 1);
2916 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
2917 ssh
->savedhost
, ssh
->savedport
,
2918 "rsa", keystr
, fingerprint
,
2919 ssh_dialog_callback
, ssh
);
2921 if (s
->dlgret
< 0) {
2925 bombout(("Unexpected data from server while waiting"
2926 " for user host key response"));
2929 } while (pktin
|| inlen
> 0);
2930 s
->dlgret
= ssh
->user_response
;
2932 ssh_set_frozen(ssh
, 0);
2934 if (s
->dlgret
== 0) {
2935 ssh
->close_expected
= TRUE
;
2936 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2941 for (i
= 0; i
< 32; i
++) {
2942 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2944 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2947 if (hostkey
.bytes
> servkey
.bytes
) {
2948 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2950 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2952 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2954 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2957 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2961 logevent("Encrypted session key");
2964 int cipher_chosen
= 0, warn
= 0;
2965 char *cipher_string
= NULL
;
2967 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2968 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2969 if (next_cipher
== CIPHER_WARN
) {
2970 /* If/when we choose a cipher, warn about it */
2972 } else if (next_cipher
== CIPHER_AES
) {
2973 /* XXX Probably don't need to mention this. */
2974 logevent("AES not supported in SSH1, skipping");
2976 switch (next_cipher
) {
2977 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2978 cipher_string
= "3DES"; break;
2979 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2980 cipher_string
= "Blowfish"; break;
2981 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2982 cipher_string
= "single-DES"; break;
2984 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2988 if (!cipher_chosen
) {
2989 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2990 bombout(("Server violates SSH 1 protocol by not "
2991 "supporting 3DES encryption"));
2993 /* shouldn't happen */
2994 bombout(("No supported ciphers found"));
2998 /* Warn about chosen cipher if necessary. */
3000 ssh_set_frozen(ssh
, 1);
3001 s
->dlgret
= askalg(ssh
->frontend
, "cipher", cipher_string
,
3002 ssh_dialog_callback
, ssh
);
3003 if (s
->dlgret
< 0) {
3007 bombout(("Unexpected data from server while waiting"
3008 " for user response"));
3011 } while (pktin
|| inlen
> 0);
3012 s
->dlgret
= ssh
->user_response
;
3014 ssh_set_frozen(ssh
, 0);
3015 if (s
->dlgret
== 0) {
3016 ssh
->close_expected
= TRUE
;
3017 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3023 switch (s
->cipher_type
) {
3024 case SSH_CIPHER_3DES
:
3025 logevent("Using 3DES encryption");
3027 case SSH_CIPHER_DES
:
3028 logevent("Using single-DES encryption");
3030 case SSH_CIPHER_BLOWFISH
:
3031 logevent("Using Blowfish encryption");
3035 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
3036 PKT_CHAR
, s
->cipher_type
,
3037 PKT_DATA
, cookie
, 8,
3038 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
3039 PKT_DATA
, s
->rsabuf
, s
->len
,
3040 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
3042 logevent("Trying to enable encryption...");
3046 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
3047 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
3049 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
3050 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
3051 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
3053 ssh
->crcda_ctx
= crcda_make_context();
3054 logevent("Installing CRC compensation attack detector");
3056 if (servkey
.modulus
) {
3057 sfree(servkey
.modulus
);
3058 servkey
.modulus
= NULL
;
3060 if (servkey
.exponent
) {
3061 sfree(servkey
.exponent
);
3062 servkey
.exponent
= NULL
;
3064 if (hostkey
.modulus
) {
3065 sfree(hostkey
.modulus
);
3066 hostkey
.modulus
= NULL
;
3068 if (hostkey
.exponent
) {
3069 sfree(hostkey
.exponent
);
3070 hostkey
.exponent
= NULL
;
3074 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3075 bombout(("Encryption not successfully enabled"));
3079 logevent("Successfully started encryption");
3083 if (!*ssh
->cfg
.username
) {
3084 if (ssh_get_line
&& !ssh_getline_pw_only
) {
3085 if (!ssh_get_line("login as: ",
3086 s
->username
, sizeof(s
->username
), FALSE
)) {
3088 * get_line failed to get a username.
3091 logevent("No username provided. Abandoning session.");
3092 ssh
->close_expected
= TRUE
;
3093 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3097 int ret
; /* need not be kept over crReturn */
3098 c_write_str(ssh
, "login as: ");
3101 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
3103 crWaitUntil(!pktin
);
3104 ret
= process_userpass_input(ssh
, in
, inlen
);
3108 c_write_str(ssh
, "\r\n");
3111 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
3112 s
->username
[sizeof(s
->username
)-1] = '\0';
3115 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
3117 char userlog
[22 + sizeof(s
->username
)];
3118 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
3120 if (flags
& FLAG_INTERACTIVE
&&
3121 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
3122 strcat(userlog
, "\r\n");
3123 c_write_str(ssh
, userlog
);
3130 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
3131 /* We must not attempt PK auth. Pretend we've already tried it. */
3132 s
->tried_publickey
= s
->tried_agent
= 1;
3134 s
->tried_publickey
= s
->tried_agent
= 0;
3136 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
3137 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
3138 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
3139 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
3140 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
3141 s
->publickey_blob
= NULL
;
3143 s
->publickey_blob
= NULL
;
3145 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
3146 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
3148 if (agent_exists() && !s
->tried_agent
) {
3150 * Attempt RSA authentication using Pageant.
3156 logevent("Pageant is running. Requesting keys.");
3158 /* Request the keys held by the agent. */
3159 PUT_32BIT(s
->request
, 1);
3160 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
3161 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
3162 ssh_agent_callback
, ssh
)) {
3166 bombout(("Unexpected data from server while waiting"
3167 " for agent response"));
3170 } while (pktin
|| inlen
> 0);
3171 r
= ssh
->agent_response
;
3172 s
->responselen
= ssh
->agent_response_len
;
3174 s
->response
= (unsigned char *) r
;
3175 if (s
->response
&& s
->responselen
>= 5 &&
3176 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3177 s
->p
= s
->response
+ 5;
3178 s
->nkeys
= GET_32BIT(s
->p
);
3180 logeventf(ssh
, "Pageant has %d SSH1 keys", s
->nkeys
);
3181 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3182 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
3183 if (s
->publickey_blob
&&
3184 !memcmp(s
->p
, s
->publickey_blob
,
3185 s
->publickey_bloblen
)) {
3186 logevent("This key matches configured key file");
3187 s
->tried_publickey
= 1;
3192 do { /* do while (0) to make breaking easy */
3193 n
= ssh1_read_bignum
3194 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3199 n
= ssh1_read_bignum
3200 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3205 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3207 s
->commentlen
= GET_32BIT(s
->p
);
3209 if (s
->responselen
- (s
->p
-s
->response
) <
3212 s
->commentp
= (char *)s
->p
;
3213 s
->p
+= s
->commentlen
;
3217 logevent("Pageant key list packet was truncated");
3221 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3222 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3224 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3225 logevent("Key refused");
3228 logevent("Received RSA challenge");
3229 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3230 bombout(("Server's RSA challenge was badly formatted"));
3235 char *agentreq
, *q
, *ret
;
3238 len
= 1 + 4; /* message type, bit count */
3239 len
+= ssh1_bignum_length(s
->key
.exponent
);
3240 len
+= ssh1_bignum_length(s
->key
.modulus
);
3241 len
+= ssh1_bignum_length(s
->challenge
);
3242 len
+= 16; /* session id */
3243 len
+= 4; /* response format */
3244 agentreq
= snewn(4 + len
, char);
3245 PUT_32BIT(agentreq
, len
);
3247 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3248 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3250 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3251 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3252 q
+= ssh1_write_bignum(q
, s
->challenge
);
3253 memcpy(q
, s
->session_id
, 16);
3255 PUT_32BIT(q
, 1); /* response format */
3256 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3257 ssh_agent_callback
, ssh
)) {
3262 bombout(("Unexpected data from server"
3263 " while waiting for agent"
3267 } while (pktin
|| inlen
> 0);
3268 vret
= ssh
->agent_response
;
3269 retlen
= ssh
->agent_response_len
;
3274 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3275 logevent("Sending Pageant's response");
3276 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3277 PKT_DATA
, ret
+ 5, 16,
3281 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3283 ("Pageant's response accepted");
3284 if (flags
& FLAG_VERBOSE
) {
3285 c_write_str(ssh
, "Authenticated using"
3287 c_write(ssh
, s
->commentp
,
3289 c_write_str(ssh
, "\" from agent\r\n");
3294 ("Pageant's response not accepted");
3297 ("Pageant failed to answer challenge");
3301 logevent("No reply received from Pageant");
3304 freebn(s
->key
.exponent
);
3305 freebn(s
->key
.modulus
);
3306 freebn(s
->challenge
);
3315 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3316 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3318 if (ssh
->cfg
.try_tis_auth
&&
3319 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3320 !s
->tis_auth_refused
) {
3321 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3322 logevent("Requested TIS authentication");
3323 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3325 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3326 logevent("TIS authentication declined");
3327 if (flags
& FLAG_INTERACTIVE
)
3328 c_write_str(ssh
, "TIS authentication refused.\r\n");
3329 s
->tis_auth_refused
= 1;
3335 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3337 bombout(("TIS challenge packet was badly formed"));
3340 logevent("Received TIS challenge");
3341 if (challengelen
> sizeof(s
->prompt
) - 1)
3342 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3343 memcpy(s
->prompt
, challenge
, challengelen
);
3344 /* Prompt heuristic comes from OpenSSH */
3345 strncpy(s
->prompt
+ challengelen
,
3346 memchr(s
->prompt
, '\n', challengelen
) ?
3347 "": "\r\nResponse: ",
3348 (sizeof s
->prompt
) - challengelen
);
3349 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3352 if (ssh
->cfg
.try_tis_auth
&&
3353 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3354 !s
->ccard_auth_refused
) {
3355 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3356 logevent("Requested CryptoCard authentication");
3357 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3359 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3360 logevent("CryptoCard authentication declined");
3361 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3362 s
->ccard_auth_refused
= 1;
3368 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3370 bombout(("CryptoCard challenge packet was badly formed"));
3373 logevent("Received CryptoCard challenge");
3374 if (challengelen
> sizeof(s
->prompt
) - 1)
3375 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3376 memcpy(s
->prompt
, challenge
, challengelen
);
3377 strncpy(s
->prompt
+ challengelen
,
3378 memchr(s
->prompt
, '\n', challengelen
) ?
3379 "" : "\r\nResponse: ",
3380 sizeof(s
->prompt
) - challengelen
);
3381 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3384 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3385 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3386 s
->username
, ssh
->savedhost
);
3388 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3389 char *comment
= NULL
;
3391 if (flags
& FLAG_VERBOSE
)
3392 c_write_str(ssh
, "Trying public key authentication.\r\n");
3393 logeventf(ssh
, "Trying public key \"%s\"",
3394 filename_to_str(&ssh
->cfg
.keyfile
));
3395 type
= key_type(&ssh
->cfg
.keyfile
);
3396 if (type
!= SSH_KEYTYPE_SSH1
) {
3397 char *msg
= dupprintf("Key is of wrong type (%s)",
3398 key_type_to_str(type
));
3400 c_write_str(ssh
, msg
);
3401 c_write_str(ssh
, "\r\n");
3403 s
->tried_publickey
= 1;
3406 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3407 if (flags
& FLAG_VERBOSE
)
3408 c_write_str(ssh
, "No passphrase required.\r\n");
3411 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3416 * Show password prompt, having first obtained it via a TIS
3417 * or CryptoCard exchange if we're doing TIS or CryptoCard
3421 if (!ssh_get_line(s
->prompt
, s
->password
,
3422 sizeof(s
->password
), TRUE
)) {
3424 * get_line failed to get a password (for example
3425 * because one was supplied on the command line
3426 * which has already failed to work). Terminate.
3428 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3429 PKT_STR
, "No more passwords available to try",
3431 logevent("Unable to authenticate");
3432 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3433 ssh
->close_expected
= TRUE
;
3434 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3438 /* Prompt may have come from server. We've munged it a bit, so
3439 * we know it to be zero-terminated at least once. */
3440 int ret
; /* need not be saved over crReturn */
3441 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3444 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3446 crWaitUntil(!pktin
);
3447 ret
= process_userpass_input(ssh
, in
, inlen
);
3451 c_write_str(ssh
, "\r\n");
3455 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3457 * Try public key authentication with the specified
3460 s
->tried_publickey
= 1;
3463 const char *error
= NULL
;
3464 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3467 c_write_str(ssh
, "Couldn't load private key from ");
3468 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3469 c_write_str(ssh
, " (");
3470 c_write_str(ssh
, error
);
3471 c_write_str(ssh
, ").\r\n");
3472 continue; /* go and try password */
3475 c_write_str(ssh
, "Wrong passphrase.\r\n");
3476 s
->tried_publickey
= 0;
3477 continue; /* try again */
3482 * Send a public key attempt.
3484 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3485 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3488 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3489 c_write_str(ssh
, "Server refused our public key.\r\n");
3490 continue; /* go and try password */
3492 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3493 bombout(("Bizarre response to offer of public key"));
3499 unsigned char buffer
[32];
3500 Bignum challenge
, response
;
3502 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3503 bombout(("Server's RSA challenge was badly formatted"));
3506 response
= rsadecrypt(challenge
, &s
->key
);
3507 freebn(s
->key
.private_exponent
);/* burn the evidence */
3509 for (i
= 0; i
< 32; i
++) {
3510 buffer
[i
] = bignum_byte(response
, 31 - i
);
3514 MD5Update(&md5c
, buffer
, 32);
3515 MD5Update(&md5c
, s
->session_id
, 16);
3516 MD5Final(buffer
, &md5c
);
3518 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3519 PKT_DATA
, buffer
, 16, PKT_END
);
3526 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3527 if (flags
& FLAG_VERBOSE
)
3528 c_write_str(ssh
, "Failed to authenticate with"
3529 " our public key.\r\n");
3530 continue; /* go and try password */
3531 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3532 bombout(("Bizarre response to RSA authentication response"));
3536 break; /* we're through! */
3538 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3540 * Defence against traffic analysis: we send a
3541 * whole bunch of packets containing strings of
3542 * different lengths. One of these strings is the
3543 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3544 * The others are all random data in
3545 * SSH1_MSG_IGNORE packets. This way a passive
3546 * listener can't tell which is the password, and
3547 * hence can't deduce the password length.
3549 * Anybody with a password length greater than 16
3550 * bytes is going to have enough entropy in their
3551 * password that a listener won't find it _that_
3552 * much help to know how long it is. So what we'll
3555 * - if password length < 16, we send 15 packets
3556 * containing string lengths 1 through 15
3558 * - otherwise, we let N be the nearest multiple
3559 * of 8 below the password length, and send 8
3560 * packets containing string lengths N through
3561 * N+7. This won't obscure the order of
3562 * magnitude of the password length, but it will
3563 * introduce a bit of extra uncertainty.
3565 * A few servers (the old 1.2.18 through 1.2.22)
3566 * can't deal with SSH1_MSG_IGNORE. For these
3567 * servers, we need an alternative defence. We make
3568 * use of the fact that the password is interpreted
3569 * as a C string: so we can append a NUL, then some
3572 * One server (a Cisco one) can deal with neither
3573 * SSH1_MSG_IGNORE _nor_ a padded password string.
3574 * For this server we are left with no defences
3575 * against password length sniffing.
3577 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3579 * The server can deal with SSH1_MSG_IGNORE, so
3580 * we can use the primary defence.
3582 int bottom
, top
, pwlen
, i
;
3585 pwlen
= strlen(s
->password
);
3587 bottom
= 0; /* zero length passwords are OK! :-) */
3590 bottom
= pwlen
& ~7;
3594 assert(pwlen
>= bottom
&& pwlen
<= top
);
3596 randomstr
= snewn(top
+ 1, char);
3598 for (i
= bottom
; i
<= top
; i
++) {
3600 defer_packet(ssh
, s
->pwpkt_type
,
3601 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3602 PKTT_OTHER
, PKT_END
);
3604 for (j
= 0; j
< i
; j
++) {
3606 randomstr
[j
] = random_byte();
3607 } while (randomstr
[j
] == '\0');
3609 randomstr
[i
] = '\0';
3610 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3611 PKT_STR
, randomstr
, PKT_END
);
3614 logevent("Sending password with camouflage packets");
3615 ssh_pkt_defersend(ssh
);
3618 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3620 * The server can't deal with SSH1_MSG_IGNORE
3621 * but can deal with padded passwords, so we
3622 * can use the secondary defence.
3628 len
= strlen(s
->password
);
3629 if (len
< sizeof(string
)) {
3631 strcpy(string
, s
->password
);
3632 len
++; /* cover the zero byte */
3633 while (len
< sizeof(string
)) {
3634 string
[len
++] = (char) random_byte();
3639 logevent("Sending length-padded password");
3640 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3641 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3642 PKTT_OTHER
, PKT_END
);
3645 * The server has _both_
3646 * BUG_CHOKES_ON_SSH1_IGNORE and
3647 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3648 * therefore nothing we can do.
3651 len
= strlen(s
->password
);
3652 logevent("Sending unpadded password");
3653 send_packet(ssh
, s
->pwpkt_type
,
3654 PKTT_PASSWORD
, PKT_INT
, len
,
3655 PKT_DATA
, s
->password
, len
,
3656 PKTT_OTHER
, PKT_END
);
3659 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3660 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3663 logevent("Sent password");
3664 memset(s
->password
, 0, strlen(s
->password
));
3666 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3667 if (flags
& FLAG_VERBOSE
)
3668 c_write_str(ssh
, "Access denied\r\n");
3669 logevent("Authentication refused");
3670 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3671 bombout(("Strange packet received, type %d", pktin
->type
));
3676 logevent("Authentication successful");
3681 void sshfwd_close(struct ssh_channel
*c
)
3685 if (ssh
->state
== SSH_STATE_CLOSED
)
3688 if (c
&& !c
->closes
) {
3690 * If halfopen is true, we have sent
3691 * CHANNEL_OPEN for this channel, but it hasn't even been
3692 * acknowledged by the server. So we must set a close flag
3693 * on it now, and then when the server acks the channel
3694 * open, we can close it then.
3697 if (ssh
->version
== 1) {
3698 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3701 struct Packet
*pktout
;
3702 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3703 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3704 ssh2_pkt_send(ssh
, pktout
);
3707 c
->closes
= 1; /* sent MSG_CLOSE */
3708 if (c
->type
== CHAN_X11
) {
3710 logevent("Forwarded X11 connection terminated");
3711 } else if (c
->type
== CHAN_SOCKDATA
||
3712 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3714 logevent("Forwarded port closed");
3719 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3723 if (ssh
->state
== SSH_STATE_CLOSED
)
3726 if (ssh
->version
== 1) {
3727 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3728 PKT_INT
, c
->remoteid
,
3730 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3731 PKTT_OTHER
, PKT_END
);
3733 * In SSH1 we can return 0 here - implying that forwarded
3734 * connections are never individually throttled - because
3735 * the only circumstance that can cause throttling will be
3736 * the whole SSH connection backing up, in which case
3737 * _everything_ will be throttled as a whole.
3741 ssh2_add_channel_data(c
, buf
, len
);
3742 return ssh2_try_send(c
);
3746 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3750 if (ssh
->state
== SSH_STATE_CLOSED
)
3753 if (ssh
->version
== 1) {
3754 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3755 c
->v
.v1
.throttling
= 0;
3756 ssh1_throttle(ssh
, -1);
3759 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3763 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3765 struct queued_handler
*qh
= ssh
->qhead
;
3769 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3772 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3773 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3776 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3777 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3781 ssh
->qhead
= qh
->next
;
3783 if (ssh
->qhead
->msg1
> 0) {
3784 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3785 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3787 if (ssh
->qhead
->msg2
> 0) {
3788 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3789 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3792 ssh
->qhead
= ssh
->qtail
= NULL
;
3793 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3796 qh
->handler(ssh
, pktin
, qh
->ctx
);
3801 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3802 chandler_fn_t handler
, void *ctx
)
3804 struct queued_handler
*qh
;
3806 qh
= snew(struct queued_handler
);
3809 qh
->handler
= handler
;
3813 if (ssh
->qtail
== NULL
) {
3817 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3818 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3821 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3822 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3825 ssh
->qtail
->next
= qh
;
3830 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3832 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3834 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3835 SSH2_MSG_REQUEST_SUCCESS
)) {
3836 logeventf(ssh
, "Remote port forwarding from %s enabled",
3839 logeventf(ssh
, "Remote port forwarding from %s refused",
3842 rpf
= del234(ssh
->rportfwds
, pf
);
3848 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3850 const char *portfwd_strptr
= cfg
->portfwd
;
3851 struct ssh_portfwd
*epf
;
3854 if (!ssh
->portfwds
) {
3855 ssh
->portfwds
= newtree234(ssh_portcmp
);
3858 * Go through the existing port forwardings and tag them
3859 * with status==DESTROY. Any that we want to keep will be
3860 * re-enabled (status==KEEP) as we go through the
3861 * configuration and find out which bits are the same as
3864 struct ssh_portfwd
*epf
;
3866 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3867 epf
->status
= DESTROY
;
3870 while (*portfwd_strptr
) {
3871 char address_family
, type
;
3872 int sport
,dport
,sserv
,dserv
;
3873 char sports
[256], dports
[256], saddr
[256], host
[256];
3876 address_family
= 'A';
3878 if (*portfwd_strptr
== 'A' ||
3879 *portfwd_strptr
== '4' ||
3880 *portfwd_strptr
== '6')
3881 address_family
= *portfwd_strptr
++;
3882 if (*portfwd_strptr
== 'L' ||
3883 *portfwd_strptr
== 'R' ||
3884 *portfwd_strptr
== 'D')
3885 type
= *portfwd_strptr
++;
3890 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3891 if (*portfwd_strptr
== ':') {
3893 * We've seen a colon in the middle of the
3894 * source port number. This means that
3895 * everything we've seen until now is the
3896 * source _address_, so we'll move it into
3897 * saddr and start sports from the beginning
3902 if (ssh
->version
== 1 && type
== 'R') {
3903 logeventf(ssh
, "SSH1 cannot handle remote source address "
3904 "spec \"%s\"; ignoring", sports
);
3906 strcpy(saddr
, sports
);
3909 if (n
< lenof(sports
)-1) sports
[n
++] = *portfwd_strptr
++;
3913 if (*portfwd_strptr
== '\t')
3916 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3917 if (n
< lenof(host
)-1) host
[n
++] = *portfwd_strptr
++;
3920 if (*portfwd_strptr
== ':')
3923 while (*portfwd_strptr
) {
3924 if (n
< lenof(dports
)-1) dports
[n
++] = *portfwd_strptr
++;
3928 dport
= atoi(dports
);
3932 dport
= net_service_lookup(dports
);
3934 logeventf(ssh
, "Service lookup failed for destination"
3935 " port \"%s\"", dports
);
3939 while (*portfwd_strptr
) portfwd_strptr
++;
3943 portfwd_strptr
++; /* eat the NUL and move to next one */
3945 sport
= atoi(sports
);
3949 sport
= net_service_lookup(sports
);
3951 logeventf(ssh
, "Service lookup failed for source"
3952 " port \"%s\"", sports
);
3955 if (sport
&& dport
) {
3956 /* Set up a description of the source port. */
3957 struct ssh_portfwd
*pfrec
, *epfrec
;
3959 pfrec
= snew(struct ssh_portfwd
);
3961 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3962 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3963 pfrec
->sport
= sport
;
3964 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3965 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3966 pfrec
->dport
= dport
;
3967 pfrec
->local
= NULL
;
3968 pfrec
->remote
= NULL
;
3969 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3970 address_family
== '6' ? ADDRTYPE_IPV6
:
3973 epfrec
= add234(ssh
->portfwds
, pfrec
);
3974 if (epfrec
!= pfrec
) {
3976 * We already have a port forwarding with precisely
3977 * these parameters. Hence, no need to do anything;
3978 * simply tag the existing one as KEEP.
3980 epfrec
->status
= KEEP
;
3981 free_portfwd(pfrec
);
3983 pfrec
->status
= CREATE
;
3989 * Now go through and destroy any port forwardings which were
3992 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3993 if (epf
->status
== DESTROY
) {
3996 message
= dupprintf("%s port forwarding from %s%s%d",
3997 epf
->type
== 'L' ?
"local" :
3998 epf
->type
== 'R' ?
"remote" : "dynamic",
3999 epf
->saddr ? epf
->saddr
: "",
4000 epf
->saddr ?
":" : "",
4003 if (epf
->type
!= 'D') {
4004 char *msg2
= dupprintf("%s to %s:%d", message
,
4005 epf
->daddr
, epf
->dport
);
4010 logeventf(ssh
, "Cancelling %s", message
);
4014 struct ssh_rportfwd
*rpf
= epf
->remote
;
4015 struct Packet
*pktout
;
4018 * Cancel the port forwarding at the server
4021 if (ssh
->version
== 1) {
4023 * We cannot cancel listening ports on the
4024 * server side in SSH1! There's no message
4025 * to support it. Instead, we simply remove
4026 * the rportfwd record from the local end
4027 * so that any connections the server tries
4028 * to make on it are rejected.
4031 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4032 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
4033 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
4035 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4036 } else if (ssh
->cfg
.rport_acceptall
) {
4037 /* XXX: ssh->cfg.rport_acceptall may not represent
4038 * what was used to open the original connection,
4039 * since it's reconfigurable. */
4040 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4042 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4044 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4045 ssh2_pkt_send(ssh
, pktout
);
4048 del234(ssh
->rportfwds
, rpf
);
4050 } else if (epf
->local
) {
4051 pfd_terminate(epf
->local
);
4054 delpos234(ssh
->portfwds
, i
);
4056 i
--; /* so we don't skip one in the list */
4060 * And finally, set up any new port forwardings (status==CREATE).
4062 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
4063 if (epf
->status
== CREATE
) {
4064 char *sportdesc
, *dportdesc
;
4065 sportdesc
= dupprintf("%s%s%s%s%d%s",
4066 epf
->saddr ? epf
->saddr
: "",
4067 epf
->saddr ?
":" : "",
4068 epf
->sserv ? epf
->sserv
: "",
4069 epf
->sserv ?
"(" : "",
4071 epf
->sserv ?
")" : "");
4072 if (epf
->type
== 'D') {
4075 dportdesc
= dupprintf("%s:%s%s%d%s",
4077 epf
->dserv ? epf
->dserv
: "",
4078 epf
->dserv ?
"(" : "",
4080 epf
->dserv ?
")" : "");
4083 if (epf
->type
== 'L') {
4084 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
4085 epf
->saddr
, epf
->sport
,
4088 epf
->addressfamily
);
4090 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
4091 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4092 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4093 sportdesc
, dportdesc
,
4094 err ?
" failed: " : "", err ? err
: "");
4095 } else if (epf
->type
== 'D') {
4096 const char *err
= pfd_addforward(NULL
, -1,
4097 epf
->saddr
, epf
->sport
,
4100 epf
->addressfamily
);
4102 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
4103 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
4104 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
4106 err ?
" failed: " : "", err ? err
: "");
4108 struct ssh_rportfwd
*pf
;
4111 * Ensure the remote port forwardings tree exists.
4113 if (!ssh
->rportfwds
) {
4114 if (ssh
->version
== 1)
4115 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
4117 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
4120 pf
= snew(struct ssh_rportfwd
);
4121 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
4122 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
4123 pf
->dport
= epf
->dport
;
4124 pf
->sport
= epf
->sport
;
4125 if (add234(ssh
->rportfwds
, pf
) != pf
) {
4126 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
4127 epf
->daddr
, epf
->dport
);
4130 logeventf(ssh
, "Requesting remote port %s"
4131 " forward to %s", sportdesc
, dportdesc
);
4133 pf
->sportdesc
= sportdesc
;
4138 if (ssh
->version
== 1) {
4139 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
4140 PKT_INT
, epf
->sport
,
4141 PKT_STR
, epf
->daddr
,
4142 PKT_INT
, epf
->dport
,
4144 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
4146 ssh_rportfwd_succfail
, pf
);
4148 struct Packet
*pktout
;
4149 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
4150 ssh2_pkt_addstring(pktout
, "tcpip-forward");
4151 ssh2_pkt_addbool(pktout
, 1);/* want reply */
4153 ssh2_pkt_addstring(pktout
, epf
->saddr
);
4154 } else if (cfg
->rport_acceptall
) {
4155 ssh2_pkt_addstring(pktout
, "0.0.0.0");
4157 ssh2_pkt_addstring(pktout
, "127.0.0.1");
4159 ssh2_pkt_adduint32(pktout
, epf
->sport
);
4160 ssh2_pkt_send(ssh
, pktout
);
4162 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4163 SSH2_MSG_REQUEST_FAILURE
,
4164 ssh_rportfwd_succfail
, pf
);
4173 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4176 int stringlen
, bufsize
;
4178 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4179 if (string
== NULL
) {
4180 bombout(("Incoming terminal data packet was badly formed"));
4184 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4186 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4187 ssh
->v1_stdout_throttling
= 1;
4188 ssh1_throttle(ssh
, +1);
4192 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4194 /* Remote side is trying to open a channel to talk to our
4195 * X-Server. Give them back a local channel number. */
4196 struct ssh_channel
*c
;
4197 int remoteid
= ssh_pkt_getuint32(pktin
);
4199 logevent("Received X11 connect request");
4200 /* Refuse if X11 forwarding is disabled. */
4201 if (!ssh
->X11_fwd_enabled
) {
4202 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4203 PKT_INT
, remoteid
, PKT_END
);
4204 logevent("Rejected X11 connect request");
4206 c
= snew(struct ssh_channel
);
4209 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4210 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4211 logevent("Opening X11 forward connection failed");
4213 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4214 PKT_INT
, remoteid
, PKT_END
);
4217 ("Opening X11 forward connection succeeded");
4218 c
->remoteid
= remoteid
;
4219 c
->halfopen
= FALSE
;
4220 c
->localid
= alloc_channel_id(ssh
);
4222 c
->v
.v1
.throttling
= 0;
4223 c
->type
= CHAN_X11
; /* identify channel type */
4224 add234(ssh
->channels
, c
);
4225 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4226 PKT_INT
, c
->remoteid
, PKT_INT
,
4227 c
->localid
, PKT_END
);
4228 logevent("Opened X11 forward channel");
4233 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4235 /* Remote side is trying to open a channel to talk to our
4236 * agent. Give them back a local channel number. */
4237 struct ssh_channel
*c
;
4238 int remoteid
= ssh_pkt_getuint32(pktin
);
4240 /* Refuse if agent forwarding is disabled. */
4241 if (!ssh
->agentfwd_enabled
) {
4242 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4243 PKT_INT
, remoteid
, PKT_END
);
4245 c
= snew(struct ssh_channel
);
4247 c
->remoteid
= remoteid
;
4248 c
->halfopen
= FALSE
;
4249 c
->localid
= alloc_channel_id(ssh
);
4251 c
->v
.v1
.throttling
= 0;
4252 c
->type
= CHAN_AGENT
; /* identify channel type */
4253 c
->u
.a
.lensofar
= 0;
4254 add234(ssh
->channels
, c
);
4255 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4256 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4261 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4263 /* Remote side is trying to open a channel to talk to a
4264 * forwarded port. Give them back a local channel number. */
4265 struct ssh_channel
*c
;
4266 struct ssh_rportfwd pf
, *pfp
;
4271 c
= snew(struct ssh_channel
);
4274 remoteid
= ssh_pkt_getuint32(pktin
);
4275 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4276 port
= ssh_pkt_getuint32(pktin
);
4278 if (hostsize
>= lenof(pf
.dhost
))
4279 hostsize
= lenof(pf
.dhost
)-1;
4280 memcpy(pf
.dhost
, host
, hostsize
);
4281 pf
.dhost
[hostsize
] = '\0';
4283 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4286 logeventf(ssh
, "Rejected remote port open request for %s:%d",
4288 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4289 PKT_INT
, remoteid
, PKT_END
);
4291 logeventf(ssh
, "Received remote port open request for %s:%d",
4293 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4294 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4296 logeventf(ssh
, "Port open failed: %s", e
);
4298 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4299 PKT_INT
, remoteid
, PKT_END
);
4301 c
->remoteid
= remoteid
;
4302 c
->halfopen
= FALSE
;
4303 c
->localid
= alloc_channel_id(ssh
);
4305 c
->v
.v1
.throttling
= 0;
4306 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4307 add234(ssh
->channels
, c
);
4308 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4309 PKT_INT
, c
->remoteid
, PKT_INT
,
4310 c
->localid
, PKT_END
);
4311 logevent("Forwarded port opened successfully");
4316 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4318 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4319 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4320 struct ssh_channel
*c
;
4322 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4323 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4324 c
->remoteid
= localid
;
4325 c
->halfopen
= FALSE
;
4326 c
->type
= CHAN_SOCKDATA
;
4327 c
->v
.v1
.throttling
= 0;
4328 pfd_confirm(c
->u
.pfd
.s
);
4331 if (c
&& c
->closes
) {
4333 * We have a pending close on this channel,
4334 * which we decided on before the server acked
4335 * the channel open. So now we know the
4336 * remoteid, we can close it again.
4338 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4339 PKT_INT
, c
->remoteid
, PKT_END
);
4343 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4345 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4346 struct ssh_channel
*c
;
4348 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4349 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4350 logevent("Forwarded connection refused by server");
4351 pfd_close(c
->u
.pfd
.s
);
4352 del234(ssh
->channels
, c
);
4357 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4359 /* Remote side closes a channel. */
4360 unsigned i
= ssh_pkt_getuint32(pktin
);
4361 struct ssh_channel
*c
;
4362 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4363 if (c
&& !c
->halfopen
) {
4366 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4368 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4369 logevent("Forwarded X11 connection terminated");
4370 assert(c
->u
.x11
.s
!= NULL
);
4371 x11_close(c
->u
.x11
.s
);
4374 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4375 logevent("Forwarded port closed");
4376 assert(c
->u
.pfd
.s
!= NULL
);
4377 pfd_close(c
->u
.pfd
.s
);
4381 c
->closes
|= (closetype
<< 2); /* seen this message */
4382 if (!(c
->closes
& closetype
)) {
4383 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4385 c
->closes
|= closetype
; /* sent it too */
4388 if (c
->closes
== 15) {
4389 del234(ssh
->channels
, c
);
4393 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4394 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4395 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4400 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4402 /* Data sent down one of our channels. */
4403 int i
= ssh_pkt_getuint32(pktin
);
4406 struct ssh_channel
*c
;
4408 ssh_pkt_getstring(pktin
, &p
, &len
);
4410 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4415 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4418 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4421 /* Data for an agent message. Buffer it. */
4423 if (c
->u
.a
.lensofar
< 4) {
4424 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4425 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4429 c
->u
.a
.lensofar
+= l
;
4431 if (c
->u
.a
.lensofar
== 4) {
4433 4 + GET_32BIT(c
->u
.a
.msglen
);
4434 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4436 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4438 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4440 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4442 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4446 c
->u
.a
.lensofar
+= l
;
4448 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4451 if (agent_query(c
->u
.a
.message
,
4454 ssh_agentf_callback
, c
))
4455 ssh_agentf_callback(c
, reply
, replylen
);
4456 sfree(c
->u
.a
.message
);
4457 c
->u
.a
.lensofar
= 0;
4460 bufsize
= 0; /* agent channels never back up */
4463 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4464 c
->v
.v1
.throttling
= 1;
4465 ssh1_throttle(ssh
, +1);
4470 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4472 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4473 logeventf(ssh
, "Server sent command exit status %d", ssh
->exitcode
);
4474 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4476 * In case `helpful' firewalls or proxies tack
4477 * extra human-readable text on the end of the
4478 * session which we might mistake for another
4479 * encrypted packet, we close the session once
4480 * we've sent EXIT_CONFIRMATION.
4482 ssh
->close_expected
= TRUE
;
4483 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4486 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4487 struct Packet
*pktin
)
4489 crBegin(ssh
->do_ssh1_connection_crstate
);
4491 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4492 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4493 ssh1_smsg_stdout_stderr_data
;
4495 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4496 ssh1_msg_channel_open_confirmation
;
4497 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4498 ssh1_msg_channel_open_failure
;
4499 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4500 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4501 ssh1_msg_channel_close
;
4502 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4503 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4505 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4506 logevent("Requesting agent forwarding");
4507 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4511 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4512 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4513 bombout(("Protocol confusion"));
4515 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4516 logevent("Agent forwarding refused");
4518 logevent("Agent forwarding enabled");
4519 ssh
->agentfwd_enabled
= TRUE
;
4520 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4524 if (ssh
->cfg
.x11_forward
) {
4525 char proto
[20], data
[64];
4526 logevent("Requesting X11 forwarding");
4527 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4528 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4529 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4530 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4531 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4532 PKT_STR
, proto
, PKT_STR
, data
,
4533 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4536 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4537 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4542 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4543 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4544 bombout(("Protocol confusion"));
4546 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4547 logevent("X11 forwarding refused");
4549 logevent("X11 forwarding enabled");
4550 ssh
->X11_fwd_enabled
= TRUE
;
4551 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4555 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4556 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4558 if (!ssh
->cfg
.nopty
) {
4559 /* Unpick the terminal-speed string. */
4560 /* XXX perhaps we should allow no speeds to be sent. */
4561 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4562 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4563 /* Send the pty request. */
4564 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4565 PKT_STR
, ssh
->cfg
.termtype
,
4566 PKT_INT
, ssh
->term_height
,
4567 PKT_INT
, ssh
->term_width
,
4568 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4569 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4570 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4571 PKT_CHAR
, 0, PKT_END
);
4572 ssh
->state
= SSH_STATE_INTERMED
;
4576 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4577 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4578 bombout(("Protocol confusion"));
4580 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4581 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4582 ssh
->editing
= ssh
->echoing
= 1;
4584 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4585 ssh
->ospeed
, ssh
->ispeed
);
4587 ssh
->editing
= ssh
->echoing
= 1;
4590 if (ssh
->cfg
.compression
) {
4591 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4595 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4596 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4597 bombout(("Protocol confusion"));
4599 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4600 c_write_str(ssh
, "Server refused to compress\r\n");
4602 logevent("Started compression");
4603 ssh
->v1_compressing
= TRUE
;
4604 ssh
->cs_comp_ctx
= zlib_compress_init();
4605 logevent("Initialised zlib (RFC1950) compression");
4606 ssh
->sc_comp_ctx
= zlib_decompress_init();
4607 logevent("Initialised zlib (RFC1950) decompression");
4611 * Start the shell or command.
4613 * Special case: if the first-choice command is an SSH2
4614 * subsystem (hence not usable here) and the second choice
4615 * exists, we fall straight back to that.
4618 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4620 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
4622 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4623 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4624 ssh
->fallback_cmd
= TRUE
;
4627 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4629 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4630 logevent("Started session");
4633 ssh
->state
= SSH_STATE_SESSION
;
4634 if (ssh
->size_needed
)
4635 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4636 if (ssh
->eof_needed
)
4637 ssh_special(ssh
, TS_EOF
);
4640 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4642 ssh
->channels
= newtree234(ssh_channelcmp
);
4646 * By this point, most incoming packets are already being
4647 * handled by the dispatch table, and we need only pay
4648 * attention to the unusual ones.
4653 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4654 /* may be from EXEC_SHELL on some servers */
4655 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4656 /* may be from EXEC_SHELL on some servers
4657 * if no pty is available or in other odd cases. Ignore */
4659 bombout(("Strange packet received: type %d", pktin
->type
));
4664 int len
= min(inlen
, 512);
4665 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4666 PKT_INT
, len
, PKT_DATA
, in
, len
,
4667 PKTT_OTHER
, PKT_END
);
4678 * Handle the top-level SSH2 protocol.
4680 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4685 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4686 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
4689 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4691 /* log reason code in disconnect message */
4695 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4696 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4699 static void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4701 /* Do nothing, because we're ignoring it! Duhh. */
4704 static void ssh1_protocol_setup(Ssh ssh
)
4709 * Most messages are handled by the coroutines.
4711 for (i
= 0; i
< 256; i
++)
4712 ssh
->packet_dispatch
[i
] = NULL
;
4715 * These special message types we install handlers for.
4717 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4718 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4719 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4722 static void ssh1_protocol(Ssh ssh
, void *vin
, int inlen
,
4723 struct Packet
*pktin
)
4725 unsigned char *in
=(unsigned char*)vin
;
4726 if (ssh
->state
== SSH_STATE_CLOSED
)
4729 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4730 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4734 if (!ssh
->protocol_initial_phase_done
) {
4735 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4736 ssh
->protocol_initial_phase_done
= TRUE
;
4741 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4745 * Utility routine for decoding comma-separated strings in KEXINIT.
4747 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4750 if (!needle
|| !haystack
) /* protect against null pointers */
4752 needlen
= strlen(needle
);
4755 * Is it at the start of the string?
4757 if (haylen
>= needlen
&& /* haystack is long enough */
4758 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4759 (haylen
== needlen
|| haystack
[needlen
] == ',')
4760 /* either , or EOS follows */
4764 * If not, search for the next comma and resume after that.
4765 * If no comma found, terminate.
4767 while (haylen
> 0 && *haystack
!= ',')
4768 haylen
--, haystack
++;
4771 haylen
--, haystack
++; /* skip over comma itself */
4776 * Similar routine for checking whether we have the first string in a list.
4778 static int first_in_commasep_string(char *needle
, char *haystack
, int haylen
)
4781 if (!needle
|| !haystack
) /* protect against null pointers */
4783 needlen
= strlen(needle
);
4785 * Is it at the start of the string?
4787 if (haylen
>= needlen
&& /* haystack is long enough */
4788 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4789 (haylen
== needlen
|| haystack
[needlen
] == ',')
4790 /* either , or EOS follows */
4798 * SSH2 key creation method.
4800 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4801 unsigned char *sessid
, char chr
,
4802 unsigned char *keyspace
)
4805 /* First 20 bytes. */
4807 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4809 SHA_Bytes(&s
, H
, 20);
4810 SHA_Bytes(&s
, &chr
, 1);
4811 SHA_Bytes(&s
, sessid
, 20);
4812 SHA_Final(&s
, keyspace
);
4813 /* Next 20 bytes. */
4815 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4817 SHA_Bytes(&s
, H
, 20);
4818 SHA_Bytes(&s
, keyspace
, 20);
4819 SHA_Final(&s
, keyspace
+ 20);
4823 * Handle the SSH2 transport layer.
4825 static int do_ssh2_transport(Ssh ssh
, void *vin
, int inlen
,
4826 struct Packet
*pktin
)
4828 unsigned char *in
= (unsigned char *)vin
;
4829 struct do_ssh2_transport_state
{
4830 int nbits
, pbits
, warn_kex
, warn_cscipher
, warn_sccipher
;
4831 Bignum p
, g
, e
, f
, K
;
4832 int kex_init_value
, kex_reply_value
;
4833 const struct ssh_mac
**maclist
;
4835 const struct ssh2_cipher
*cscipher_tobe
;
4836 const struct ssh2_cipher
*sccipher_tobe
;
4837 const struct ssh_mac
*csmac_tobe
;
4838 const struct ssh_mac
*scmac_tobe
;
4839 const struct ssh_compress
*cscomp_tobe
;
4840 const struct ssh_compress
*sccomp_tobe
;
4841 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4842 int hostkeylen
, siglen
;
4843 void *hkey
; /* actual host key */
4844 unsigned char exchange_hash
[20];
4845 int n_preferred_kex
;
4846 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4847 int n_preferred_ciphers
;
4848 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4849 const struct ssh_compress
*preferred_comp
;
4850 int got_session_id
, activated_authconn
;
4851 struct Packet
*pktout
;
4856 crState(do_ssh2_transport_state
);
4858 crBegin(ssh
->do_ssh2_transport_crstate
);
4860 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4861 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4862 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4864 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4867 * Be prepared to work around the buggy MAC problem.
4869 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4870 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4872 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4875 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4877 int i
, j
, commalist_started
;
4880 * Set up the preferred key exchange. (NULL => warn below here)
4882 s
->n_preferred_kex
= 0;
4883 for (i
= 0; i
< KEX_MAX
; i
++) {
4884 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4886 s
->preferred_kex
[s
->n_preferred_kex
++] =
4887 &ssh_diffiehellman_gex
;
4890 s
->preferred_kex
[s
->n_preferred_kex
++] =
4891 &ssh_diffiehellman_group14
;
4894 s
->preferred_kex
[s
->n_preferred_kex
++] =
4895 &ssh_diffiehellman_group1
;
4898 /* Flag for later. Don't bother if it's the last in
4900 if (i
< KEX_MAX
- 1) {
4901 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4908 * Set up the preferred ciphers. (NULL => warn below here)
4910 s
->n_preferred_ciphers
= 0;
4911 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4912 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4913 case CIPHER_BLOWFISH
:
4914 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4917 if (ssh
->cfg
.ssh2_des_cbc
) {
4918 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4922 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4925 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4928 /* Flag for later. Don't bother if it's the last in
4930 if (i
< CIPHER_MAX
- 1) {
4931 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4938 * Set up preferred compression.
4940 if (ssh
->cfg
.compression
)
4941 s
->preferred_comp
= &ssh_zlib
;
4943 s
->preferred_comp
= &ssh_comp_none
;
4946 * Enable queueing of outgoing auth- or connection-layer
4947 * packets while we are in the middle of a key exchange.
4949 ssh
->queueing
= TRUE
;
4952 * Flag that KEX is in progress.
4954 ssh
->kex_in_progress
= TRUE
;
4957 * Construct and send our key exchange packet.
4959 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4960 for (i
= 0; i
< 16; i
++)
4961 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4962 /* List key exchange algorithms. */
4963 ssh2_pkt_addstring_start(s
->pktout
);
4964 commalist_started
= 0;
4965 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4966 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4967 if (!k
) continue; /* warning flag */
4968 if (commalist_started
)
4969 ssh2_pkt_addstring_str(s
->pktout
, ",");
4970 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4971 commalist_started
= 1;
4973 /* List server host key algorithms. */
4974 ssh2_pkt_addstring_start(s
->pktout
);
4975 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4976 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4977 if (i
< lenof(hostkey_algs
) - 1)
4978 ssh2_pkt_addstring_str(s
->pktout
, ",");
4980 /* List client->server encryption algorithms. */
4981 ssh2_pkt_addstring_start(s
->pktout
);
4982 commalist_started
= 0;
4983 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4984 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4985 if (!c
) continue; /* warning flag */
4986 for (j
= 0; j
< c
->nciphers
; j
++) {
4987 if (commalist_started
)
4988 ssh2_pkt_addstring_str(s
->pktout
, ",");
4989 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4990 commalist_started
= 1;
4993 /* List server->client encryption algorithms. */
4994 ssh2_pkt_addstring_start(s
->pktout
);
4995 commalist_started
= 0;
4996 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4997 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4998 if (!c
) continue; /* warning flag */
4999 for (j
= 0; j
< c
->nciphers
; j
++) {
5000 if (commalist_started
)
5001 ssh2_pkt_addstring_str(s
->pktout
, ",");
5002 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
5003 commalist_started
= 1;
5006 /* List client->server MAC algorithms. */
5007 ssh2_pkt_addstring_start(s
->pktout
);
5008 for (i
= 0; i
< s
->nmacs
; i
++) {
5009 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5010 if (i
< s
->nmacs
- 1)
5011 ssh2_pkt_addstring_str(s
->pktout
, ",");
5013 /* List server->client MAC algorithms. */
5014 ssh2_pkt_addstring_start(s
->pktout
);
5015 for (i
= 0; i
< s
->nmacs
; i
++) {
5016 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
5017 if (i
< s
->nmacs
- 1)
5018 ssh2_pkt_addstring_str(s
->pktout
, ",");
5020 /* List client->server compression algorithms. */
5021 ssh2_pkt_addstring_start(s
->pktout
);
5022 assert(lenof(compressions
) > 1);
5023 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5024 for (i
= 0; i
< lenof(compressions
); i
++) {
5025 const struct ssh_compress
*c
= compressions
[i
];
5026 if (c
!= s
->preferred_comp
) {
5027 ssh2_pkt_addstring_str(s
->pktout
, ",");
5028 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5031 /* List server->client compression algorithms. */
5032 ssh2_pkt_addstring_start(s
->pktout
);
5033 assert(lenof(compressions
) > 1);
5034 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
5035 for (i
= 0; i
< lenof(compressions
); i
++) {
5036 const struct ssh_compress
*c
= compressions
[i
];
5037 if (c
!= s
->preferred_comp
) {
5038 ssh2_pkt_addstring_str(s
->pktout
, ",");
5039 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
5042 /* List client->server languages. Empty list. */
5043 ssh2_pkt_addstring_start(s
->pktout
);
5044 /* List server->client languages. Empty list. */
5045 ssh2_pkt_addstring_start(s
->pktout
);
5046 /* First KEX packet does _not_ follow, because we're not that brave. */
5047 ssh2_pkt_addbool(s
->pktout
, FALSE
);
5049 ssh2_pkt_adduint32(s
->pktout
, 0);
5052 ssh
->exhash
= ssh
->exhashbase
;
5053 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
5055 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5059 if (pktin
->length
> 5)
5060 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
5063 * Now examine the other side's KEXINIT to see what we're up
5067 char *str
, *preferred
;
5070 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
5071 bombout(("expected key exchange packet from server"));
5075 ssh
->hostkey
= NULL
;
5076 s
->cscipher_tobe
= NULL
;
5077 s
->sccipher_tobe
= NULL
;
5078 s
->csmac_tobe
= NULL
;
5079 s
->scmac_tobe
= NULL
;
5080 s
->cscomp_tobe
= NULL
;
5081 s
->sccomp_tobe
= NULL
;
5082 s
->warn_kex
= s
->warn_cscipher
= s
->warn_sccipher
= FALSE
;
5084 pktin
->savedpos
+= 16; /* skip garbage cookie */
5085 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
5088 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
5089 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
5093 if (!preferred
) preferred
= k
->name
;
5094 if (in_commasep_string(k
->name
, str
, len
))
5101 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
5102 str ? str
: "(null)"));
5106 * Note that the server's guess is considered wrong if it doesn't match
5107 * the first algorithm in our list, even if it's still the algorithm
5110 s
->guessok
= first_in_commasep_string(preferred
, str
, len
);
5111 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
5112 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
5113 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
5114 ssh
->hostkey
= hostkey_algs
[i
];
5118 s
->guessok
= s
->guessok
&&
5119 first_in_commasep_string(hostkey_algs
[0]->name
, str
, len
);
5120 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
5121 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5122 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5124 s
->warn_cscipher
= TRUE
;
5126 for (j
= 0; j
< c
->nciphers
; j
++) {
5127 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5128 s
->cscipher_tobe
= c
->list
[j
];
5133 if (s
->cscipher_tobe
)
5136 if (!s
->cscipher_tobe
) {
5137 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
5138 str ? str
: "(null)"));
5142 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
5143 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
5144 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
5146 s
->warn_sccipher
= TRUE
;
5148 for (j
= 0; j
< c
->nciphers
; j
++) {
5149 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
5150 s
->sccipher_tobe
= c
->list
[j
];
5155 if (s
->sccipher_tobe
)
5158 if (!s
->sccipher_tobe
) {
5159 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
5160 str ? str
: "(null)"));
5164 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
5165 for (i
= 0; i
< s
->nmacs
; i
++) {
5166 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5167 s
->csmac_tobe
= s
->maclist
[i
];
5171 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
5172 for (i
= 0; i
< s
->nmacs
; i
++) {
5173 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
5174 s
->scmac_tobe
= s
->maclist
[i
];
5178 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5179 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5180 const struct ssh_compress
*c
=
5181 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5182 if (in_commasep_string(c
->name
, str
, len
)) {
5187 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5188 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5189 const struct ssh_compress
*c
=
5190 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5191 if (in_commasep_string(c
->name
, str
, len
)) {
5196 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server language */
5197 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client language */
5198 s
->ignorepkt
= ssh2_pkt_getbool(pktin
) && !s
->guessok
;
5201 ssh_set_frozen(ssh
, 1);
5202 s
->dlgret
= askalg(ssh
->frontend
, "key-exchange algorithm",
5204 ssh_dialog_callback
, ssh
);
5205 if (s
->dlgret
< 0) {
5209 bombout(("Unexpected data from server while"
5210 " waiting for user response"));
5213 } while (pktin
|| inlen
> 0);
5214 s
->dlgret
= ssh
->user_response
;
5216 ssh_set_frozen(ssh
, 0);
5217 if (s
->dlgret
== 0) {
5218 ssh
->close_expected
= TRUE
;
5219 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5224 if (s
->warn_cscipher
) {
5225 ssh_set_frozen(ssh
, 1);
5226 s
->dlgret
= askalg(ssh
->frontend
,
5227 "client-to-server cipher",
5228 s
->cscipher_tobe
->name
,
5229 ssh_dialog_callback
, ssh
);
5230 if (s
->dlgret
< 0) {
5234 bombout(("Unexpected data from server while"
5235 " waiting for user response"));
5238 } while (pktin
|| inlen
> 0);
5239 s
->dlgret
= ssh
->user_response
;
5241 ssh_set_frozen(ssh
, 0);
5242 if (s
->dlgret
== 0) {
5243 ssh
->close_expected
= TRUE
;
5244 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5249 if (s
->warn_sccipher
) {
5250 ssh_set_frozen(ssh
, 1);
5251 s
->dlgret
= askalg(ssh
->frontend
,
5252 "server-to-client cipher",
5253 s
->sccipher_tobe
->name
,
5254 ssh_dialog_callback
, ssh
);
5255 if (s
->dlgret
< 0) {
5259 bombout(("Unexpected data from server while"
5260 " waiting for user response"));
5263 } while (pktin
|| inlen
> 0);
5264 s
->dlgret
= ssh
->user_response
;
5266 ssh_set_frozen(ssh
, 0);
5267 if (s
->dlgret
== 0) {
5268 ssh
->close_expected
= TRUE
;
5269 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5274 if (s
->ignorepkt
) /* first_kex_packet_follows */
5275 crWaitUntil(pktin
); /* Ignore packet */
5279 * Work out the number of bits of key we will need from the key
5280 * exchange. We start with the maximum key length of either
5286 csbits
= s
->cscipher_tobe
->keylen
;
5287 scbits
= s
->sccipher_tobe
->keylen
;
5288 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5290 /* The keys only have 160-bit entropy, since they're based on
5291 * a SHA-1 hash. So cap the key size at 160 bits. */
5296 * If we're doing Diffie-Hellman group exchange, start by
5297 * requesting a group.
5299 if (!ssh
->kex
->pdata
) {
5300 logevent("Doing Diffie-Hellman group exchange");
5301 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5303 * Work out how big a DH group we will need to allow that
5306 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5307 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5308 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5309 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5312 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5313 bombout(("expected key exchange group packet from server"));
5316 s
->p
= ssh2_pkt_getmp(pktin
);
5317 s
->g
= ssh2_pkt_getmp(pktin
);
5318 if (!s
->p
|| !s
->g
) {
5319 bombout(("unable to read mp-ints from incoming group packet"));
5322 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5323 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5324 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5326 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5327 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5328 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5329 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5330 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5331 ssh
->kex
->groupname
);
5334 logevent("Doing Diffie-Hellman key exchange");
5336 * Now generate and send e for Diffie-Hellman.
5338 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* this can take a while */
5339 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5340 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5341 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5342 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5344 set_busy_status(ssh
->frontend
, BUSY_WAITING
); /* wait for server */
5346 if (pktin
->type
!= s
->kex_reply_value
) {
5347 bombout(("expected key exchange reply packet from server"));
5350 set_busy_status(ssh
->frontend
, BUSY_CPU
); /* cogitate */
5351 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5352 s
->f
= ssh2_pkt_getmp(pktin
);
5354 bombout(("unable to parse key exchange reply packet"));
5357 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5359 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5361 /* We assume everything from now on will be quick, and it might
5362 * involve user interaction. */
5363 set_busy_status(ssh
->frontend
, BUSY_NOT
);
5365 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5366 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5367 sha_uint32(&ssh
->exhash
, s
->pbits
);
5368 sha_mpint(&ssh
->exhash
, s
->p
);
5369 sha_mpint(&ssh
->exhash
, s
->g
);
5371 sha_mpint(&ssh
->exhash
, s
->e
);
5372 sha_mpint(&ssh
->exhash
, s
->f
);
5373 sha_mpint(&ssh
->exhash
, s
->K
);
5374 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5376 dh_cleanup(ssh
->kex_ctx
);
5377 ssh
->kex_ctx
= NULL
;
5380 debug(("Exchange hash is:\n"));
5381 dmemdump(s
->exchange_hash
, 20);
5384 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5386 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5387 (char *)s
->exchange_hash
, 20)) {
5388 bombout(("Server's host key did not match the signature supplied"));
5393 * Authenticate remote host: verify host key. (We've already
5394 * checked the signature of the exchange hash.)
5396 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5397 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5398 ssh_set_frozen(ssh
, 1);
5399 s
->dlgret
= verify_ssh_host_key(ssh
->frontend
,
5400 ssh
->savedhost
, ssh
->savedport
,
5401 ssh
->hostkey
->keytype
, s
->keystr
,
5403 ssh_dialog_callback
, ssh
);
5404 if (s
->dlgret
< 0) {
5408 bombout(("Unexpected data from server while waiting"
5409 " for user host key response"));
5412 } while (pktin
|| inlen
> 0);
5413 s
->dlgret
= ssh
->user_response
;
5415 ssh_set_frozen(ssh
, 0);
5416 if (s
->dlgret
== 0) {
5417 ssh
->close_expected
= TRUE
;
5418 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5421 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5422 logevent("Host key fingerprint is:");
5423 logevent(s
->fingerprint
);
5425 sfree(s
->fingerprint
);
5427 ssh
->hostkey
->freekey(s
->hkey
);
5430 * The exchange hash from the very first key exchange is also
5431 * the session id, used in session key construction and
5434 if (!s
->got_session_id
) {
5435 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5436 sizeof(s
->exchange_hash
));
5437 s
->got_session_id
= TRUE
;
5441 * Send SSH2_MSG_NEWKEYS.
5443 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5444 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5445 ssh
->outgoing_data_size
= 0; /* start counting from here */
5448 * We've sent client NEWKEYS, so create and initialise
5449 * client-to-server session keys.
5451 if (ssh
->cs_cipher_ctx
)
5452 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5453 ssh
->cscipher
= s
->cscipher_tobe
;
5454 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5456 if (ssh
->cs_mac_ctx
)
5457 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5458 ssh
->csmac
= s
->csmac_tobe
;
5459 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5461 if (ssh
->cs_comp_ctx
)
5462 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5463 ssh
->cscomp
= s
->cscomp_tobe
;
5464 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5467 * Set IVs on client-to-server keys. Here we use the exchange
5468 * hash from the _first_ key exchange.
5471 unsigned char keyspace
[40];
5472 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5473 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5474 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5475 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5476 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5477 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5480 logeventf(ssh
, "Initialised %.200s client->server encryption",
5481 ssh
->cscipher
->text_name
);
5482 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5483 ssh
->csmac
->text_name
);
5484 if (ssh
->cscomp
->text_name
)
5485 logeventf(ssh
, "Initialised %s compression",
5486 ssh
->cscomp
->text_name
);
5489 * Now our end of the key exchange is complete, we can send all
5490 * our queued higher-layer packets.
5492 ssh
->queueing
= FALSE
;
5493 ssh2_pkt_queuesend(ssh
);
5496 * Expect SSH2_MSG_NEWKEYS from server.
5499 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5500 bombout(("expected new-keys packet from server"));
5503 ssh
->incoming_data_size
= 0; /* start counting from here */
5506 * We've seen server NEWKEYS, so create and initialise
5507 * server-to-client session keys.
5509 if (ssh
->sc_cipher_ctx
)
5510 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5511 ssh
->sccipher
= s
->sccipher_tobe
;
5512 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5514 if (ssh
->sc_mac_ctx
)
5515 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5516 ssh
->scmac
= s
->scmac_tobe
;
5517 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5519 if (ssh
->sc_comp_ctx
)
5520 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5521 ssh
->sccomp
= s
->sccomp_tobe
;
5522 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5525 * Set IVs on server-to-client keys. Here we use the exchange
5526 * hash from the _first_ key exchange.
5529 unsigned char keyspace
[40];
5530 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5531 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5532 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5533 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5534 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5535 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5537 logeventf(ssh
, "Initialised %.200s server->client encryption",
5538 ssh
->sccipher
->text_name
);
5539 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5540 ssh
->scmac
->text_name
);
5541 if (ssh
->sccomp
->text_name
)
5542 logeventf(ssh
, "Initialised %s decompression",
5543 ssh
->sccomp
->text_name
);
5546 * Free key exchange data.
5550 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5556 * Key exchange is over. Loop straight back round if we have a
5557 * deferred rekey reason.
5559 if (ssh
->deferred_rekey_reason
) {
5560 logevent(ssh
->deferred_rekey_reason
);
5562 ssh
->deferred_rekey_reason
= NULL
;
5563 goto begin_key_exchange
;
5567 * Otherwise, schedule a timer for our next rekey.
5569 ssh
->kex_in_progress
= FALSE
;
5570 ssh
->last_rekey
= GETTICKCOUNT();
5571 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5572 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5576 * If this is the first key exchange phase, we must pass the
5577 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5578 * wants to see it but because it will need time to initialise
5579 * itself before it sees an actual packet. In subsequent key
5580 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5581 * it would only confuse the layer above.
5583 if (s
->activated_authconn
) {
5586 s
->activated_authconn
= TRUE
;
5589 * Now we're encrypting. Begin returning 1 to the protocol main
5590 * function so that other things can run on top of the
5591 * transport. If we ever see a KEXINIT, we must go back to the
5594 * We _also_ go back to the start if we see pktin==NULL and
5595 * inlen==-1, because this is a special signal meaning
5596 * `initiate client-driven rekey', and `in' contains a message
5597 * giving the reason for the rekey.
5599 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5600 (!pktin
&& inlen
== -1))) {
5605 logevent("Server initiated key re-exchange");
5608 * Special case: if the server bug is set that doesn't
5609 * allow rekeying, we give a different log message and
5610 * continue waiting. (If such a server _initiates_ a rekey,
5611 * we process it anyway!)
5613 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5614 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5616 /* Reset the counters, so that at least this message doesn't
5617 * hit the event log _too_ often. */
5618 ssh
->outgoing_data_size
= 0;
5619 ssh
->incoming_data_size
= 0;
5620 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5622 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5625 goto wait_for_rekey
; /* this is utterly horrid */
5627 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5630 goto begin_key_exchange
;
5636 * Add data to an SSH2 channel output buffer.
5638 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5641 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5645 * Attempt to send data on an SSH2 channel.
5647 static int ssh2_try_send(struct ssh_channel
*c
)
5650 struct Packet
*pktout
;
5652 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5655 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5656 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5657 len
= c
->v
.v2
.remwindow
;
5658 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5659 len
= c
->v
.v2
.remmaxpkt
;
5660 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5661 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5662 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5663 ssh2_pkt_addstring_start(pktout
);
5664 ssh2_pkt_addstring_data(pktout
, data
, len
);
5665 end_log_omission(ssh
, pktout
);
5666 ssh2_pkt_send(ssh
, pktout
);
5667 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5668 c
->v
.v2
.remwindow
-= len
;
5672 * After having sent as much data as we can, return the amount
5675 return bufchain_size(&c
->v
.v2
.outbuffer
);
5679 * Potentially enlarge the window on an SSH2 channel.
5681 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5686 * Never send WINDOW_ADJUST for a channel that the remote side
5687 * already thinks it's closed; there's no point, since it won't
5688 * be sending any more data anyway.
5694 * Only send a WINDOW_ADJUST if there's significantly more window
5695 * available than the other end thinks there is. This saves us
5696 * sending a WINDOW_ADJUST for every character in a shell session.
5698 * "Significant" is arbitrarily defined as half the window size.
5700 if (newwin
> c
->v
.v2
.locwindow
* 2) {
5701 struct Packet
*pktout
;
5703 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5704 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5705 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5706 ssh2_pkt_send(ssh
, pktout
);
5707 c
->v
.v2
.locwindow
= newwin
;
5711 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5713 unsigned i
= ssh_pkt_getuint32(pktin
);
5714 struct ssh_channel
*c
;
5715 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5716 if (c
&& !c
->closes
)
5717 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5720 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5724 unsigned i
= ssh_pkt_getuint32(pktin
);
5725 struct ssh_channel
*c
;
5726 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5728 return; /* nonexistent channel */
5729 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5730 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5731 return; /* extended but not stderr */
5732 ssh_pkt_getstring(pktin
, &data
, &length
);
5735 c
->v
.v2
.locwindow
-= length
;
5737 case CHAN_MAINSESSION
:
5739 from_backend(ssh
->frontend
, pktin
->type
==
5740 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5744 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5747 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5750 while (length
> 0) {
5751 if (c
->u
.a
.lensofar
< 4) {
5752 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5753 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5757 c
->u
.a
.lensofar
+= l
;
5759 if (c
->u
.a
.lensofar
== 4) {
5761 4 + GET_32BIT(c
->u
.a
.msglen
);
5762 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5764 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5766 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5768 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5770 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5774 c
->u
.a
.lensofar
+= l
;
5776 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5779 if (agent_query(c
->u
.a
.message
,
5782 ssh_agentf_callback
, c
))
5783 ssh_agentf_callback(c
, reply
, replylen
);
5784 sfree(c
->u
.a
.message
);
5785 c
->u
.a
.lensofar
= 0;
5792 * If we are not buffering too much data,
5793 * enlarge the window again at the remote side.
5795 if (bufsize
< OUR_V2_WINSIZE
)
5796 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5800 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5802 unsigned i
= ssh_pkt_getuint32(pktin
);
5803 struct ssh_channel
*c
;
5805 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5807 return; /* nonexistent channel */
5809 if (c
->type
== CHAN_X11
) {
5811 * Remote EOF on an X11 channel means we should
5812 * wrap up and close the channel ourselves.
5814 x11_close(c
->u
.x11
.s
);
5816 } else if (c
->type
== CHAN_AGENT
) {
5818 } else if (c
->type
== CHAN_SOCKDATA
) {
5819 pfd_close(c
->u
.pfd
.s
);
5824 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5826 unsigned i
= ssh_pkt_getuint32(pktin
);
5827 struct ssh_channel
*c
;
5828 struct Packet
*pktout
;
5830 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5831 if (!c
|| c
->halfopen
) {
5832 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5833 c ?
"half-open" : "nonexistent", i
));
5836 /* Do pre-close processing on the channel. */
5838 case CHAN_MAINSESSION
:
5839 ssh
->mainchan
= NULL
;
5840 update_specials_menu(ssh
->frontend
);
5843 if (c
->u
.x11
.s
!= NULL
)
5844 x11_close(c
->u
.x11
.s
);
5851 if (c
->u
.pfd
.s
!= NULL
)
5852 pfd_close(c
->u
.pfd
.s
);
5856 if (c
->closes
== 0) {
5857 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5858 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5859 ssh2_pkt_send(ssh
, pktout
);
5861 del234(ssh
->channels
, c
);
5862 bufchain_clear(&c
->v
.v2
.outbuffer
);
5866 * See if that was the last channel left open.
5867 * (This is only our termination condition if we're
5868 * not running in -N mode.)
5870 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5871 logevent("All channels closed. Disconnecting");
5874 * We used to send SSH_MSG_DISCONNECT here,
5875 * because I'd believed that _every_ conforming
5876 * SSH2 connection had to end with a disconnect
5877 * being sent by at least one side; apparently
5878 * I was wrong and it's perfectly OK to
5879 * unceremoniously slam the connection shut
5880 * when you're done, and indeed OpenSSH feels
5881 * this is more polite than sending a
5882 * DISCONNECT. So now we don't.
5884 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5885 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5886 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5887 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5888 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5890 ssh
->close_expected
= TRUE
;
5891 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5895 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5897 unsigned i
= ssh_pkt_getuint32(pktin
);
5898 struct ssh_channel
*c
;
5899 struct Packet
*pktout
;
5901 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5903 return; /* nonexistent channel */
5904 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5905 return; /* dunno why they're confirming this */
5906 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5907 c
->halfopen
= FALSE
;
5908 c
->type
= CHAN_SOCKDATA
;
5909 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5910 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5912 pfd_confirm(c
->u
.pfd
.s
);
5915 * We have a pending close on this channel,
5916 * which we decided on before the server acked
5917 * the channel open. So now we know the
5918 * remoteid, we can close it again.
5920 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5921 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5922 ssh2_pkt_send(ssh
, pktout
);
5926 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5928 static const char *const reasons
[] = {
5929 "<unknown reason code>",
5930 "Administratively prohibited",
5932 "Unknown channel type",
5933 "Resource shortage",
5935 unsigned i
= ssh_pkt_getuint32(pktin
);
5936 unsigned reason_code
;
5937 char *reason_string
;
5939 struct ssh_channel
*c
;
5940 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5942 return; /* nonexistent channel */
5943 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5944 return; /* dunno why they're failing this */
5946 reason_code
= ssh_pkt_getuint32(pktin
);
5947 if (reason_code
>= lenof(reasons
))
5948 reason_code
= 0; /* ensure reasons[reason_code] in range */
5949 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5950 logeventf(ssh
, "Forwarded connection refused by server: %s [%.*s]",
5951 reasons
[reason_code
], reason_length
, reason_string
);
5953 pfd_close(c
->u
.pfd
.s
);
5955 del234(ssh
->channels
, c
);
5959 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5963 int typelen
, want_reply
;
5964 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5965 struct ssh_channel
*c
;
5966 struct Packet
*pktout
;
5968 localid
= ssh_pkt_getuint32(pktin
);
5969 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5970 want_reply
= ssh2_pkt_getbool(pktin
);
5973 * First, check that the channel exists. Otherwise,
5974 * we can instantly disconnect with a rude message.
5976 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5979 sprintf(buf
, "Received channel request for nonexistent"
5980 " channel %d", localid
);
5982 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5983 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5984 ssh2_pkt_addstring(pktout
, buf
);
5985 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5986 ssh2_pkt_send_noqueue(ssh
, pktout
);
5987 connection_fatal(ssh
->frontend
, "%s", buf
);
5988 ssh
->close_expected
= TRUE
;
5989 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5994 * Having got the channel number, we now look at
5995 * the request type string to see if it's something
5998 if (c
== ssh
->mainchan
) {
6000 * We recognise "exit-status" and "exit-signal" on
6001 * the primary channel.
6003 if (typelen
== 11 &&
6004 !memcmp(type
, "exit-status", 11)) {
6006 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
6007 logeventf(ssh
, "Server sent command exit status %d",
6009 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6011 } else if (typelen
== 11 &&
6012 !memcmp(type
, "exit-signal", 11)) {
6014 int is_plausible
= TRUE
, is_int
= FALSE
;
6015 char *fmt_sig
= "", *fmt_msg
= "";
6017 int msglen
= 0, core
= FALSE
;
6018 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
6019 * provide an `int' for the signal, despite its
6020 * having been a `string' in the drafts since at
6021 * least 2001. (Fixed in session.c 1.147.) Try to
6022 * infer which we can safely parse it as. */
6024 unsigned char *p
= pktin
->body
+
6026 long len
= pktin
->length
- pktin
->savedpos
;
6027 unsigned long num
= GET_32BIT(p
); /* what is it? */
6028 /* If it's 0, it hardly matters; assume string */
6032 int maybe_int
= FALSE
, maybe_str
= FALSE
;
6033 #define CHECK_HYPOTHESIS(offset, result) \
6036 if (q >= 0 && q+4 <= len) { \
6037 q = q + 4 + GET_32BIT(p+q); \
6038 if (q >= 0 && q+4 <= len && \
6039 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
6043 CHECK_HYPOTHESIS(4+1, maybe_int
);
6044 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
6045 #undef CHECK_HYPOTHESIS
6046 if (maybe_int
&& !maybe_str
)
6048 else if (!maybe_int
&& maybe_str
)
6051 /* Crikey. Either or neither. Panic. */
6052 is_plausible
= FALSE
;
6057 /* Old non-standard OpenSSH. */
6058 int signum
= ssh_pkt_getuint32(pktin
);
6059 fmt_sig
= dupprintf(" %d", signum
);
6061 /* As per the drafts. */
6064 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
6065 /* Signal name isn't supposed to be blank, but
6066 * let's cope gracefully if it is. */
6068 fmt_sig
= dupprintf(" \"%.*s\"",
6072 core
= ssh2_pkt_getbool(pktin
);
6073 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
6075 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
6077 /* ignore lang tag */
6078 } /* else don't attempt to parse */
6079 logeventf(ssh
, "Server exited on signal%s%s%s",
6080 fmt_sig
, core ?
" (core dumped)" : "",
6082 if (*fmt_sig
) sfree(fmt_sig
);
6083 if (*fmt_msg
) sfree(fmt_msg
);
6084 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
6089 * This is a channel request we don't know
6090 * about, so we now either ignore the request
6091 * or respond with CHANNEL_FAILURE, depending
6094 reply
= SSH2_MSG_CHANNEL_FAILURE
;
6097 pktout
= ssh2_pkt_init(reply
);
6098 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6099 ssh2_pkt_send(ssh
, pktout
);
6103 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
6106 int typelen
, want_reply
;
6107 struct Packet
*pktout
;
6109 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6110 want_reply
= ssh2_pkt_getbool(pktin
);
6113 * We currently don't support any global requests
6114 * at all, so we either ignore the request or
6115 * respond with REQUEST_FAILURE, depending on
6119 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
6120 ssh2_pkt_send(ssh
, pktout
);
6124 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
6132 struct ssh_channel
*c
;
6133 unsigned remid
, winsize
, pktsize
;
6134 struct Packet
*pktout
;
6136 ssh_pkt_getstring(pktin
, &type
, &typelen
);
6137 c
= snew(struct ssh_channel
);
6140 remid
= ssh_pkt_getuint32(pktin
);
6141 winsize
= ssh_pkt_getuint32(pktin
);
6142 pktsize
= ssh_pkt_getuint32(pktin
);
6144 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
6147 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6148 addrstr
= snewn(peeraddrlen
+1, char);
6149 memcpy(addrstr
, peeraddr
, peeraddrlen
);
6150 addrstr
[peeraddrlen
] = '\0';
6151 peerport
= ssh_pkt_getuint32(pktin
);
6153 logeventf(ssh
, "Received X11 connect request from %s:%d",
6156 if (!ssh
->X11_fwd_enabled
)
6157 error
= "X11 forwarding is not enabled";
6158 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
6159 ssh
->x11auth
, addrstr
, peerport
,
6160 &ssh
->cfg
) != NULL
) {
6161 error
= "Unable to open an X11 connection";
6163 logevent("Opening X11 forward connection succeeded");
6168 } else if (typelen
== 15 &&
6169 !memcmp(type
, "forwarded-tcpip", 15)) {
6170 struct ssh_rportfwd pf
, *realpf
;
6173 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
6174 pf
.sport
= ssh_pkt_getuint32(pktin
);
6175 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
6176 peerport
= ssh_pkt_getuint32(pktin
);
6177 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
6178 logeventf(ssh
, "Received remote port %d open request "
6179 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
6180 if (realpf
== NULL
) {
6181 error
= "Remote port is not recognised";
6183 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
6187 realpf
->pfrec
->addressfamily
);
6188 logeventf(ssh
, "Attempting to forward remote port to "
6189 "%s:%d", realpf
->dhost
, realpf
->dport
);
6191 logeventf(ssh
, "Port open failed: %s", e
);
6192 error
= "Port open failed";
6194 logevent("Forwarded port opened successfully");
6195 c
->type
= CHAN_SOCKDATA
;
6198 } else if (typelen
== 22 &&
6199 !memcmp(type
, "auth-agent@openssh.com", 3)) {
6200 if (!ssh
->agentfwd_enabled
)
6201 error
= "Agent forwarding is not enabled";
6203 c
->type
= CHAN_AGENT
; /* identify channel type */
6204 c
->u
.a
.lensofar
= 0;
6207 error
= "Unsupported channel type requested";
6210 c
->remoteid
= remid
;
6211 c
->halfopen
= FALSE
;
6213 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
6214 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6215 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
6216 ssh2_pkt_addstring(pktout
, error
);
6217 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
6218 ssh2_pkt_send(ssh
, pktout
);
6219 logeventf(ssh
, "Rejected channel open: %s", error
);
6222 c
->localid
= alloc_channel_id(ssh
);
6224 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6225 c
->v
.v2
.remwindow
= winsize
;
6226 c
->v
.v2
.remmaxpkt
= pktsize
;
6227 bufchain_init(&c
->v
.v2
.outbuffer
);
6228 add234(ssh
->channels
, c
);
6229 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
6230 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
6231 ssh2_pkt_adduint32(pktout
, c
->localid
);
6232 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
6233 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
6234 ssh2_pkt_send(ssh
, pktout
);
6239 * Handle the SSH2 userauth and connection layers.
6241 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
6242 struct Packet
*pktin
)
6244 struct do_ssh2_authconn_state
{
6246 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
6248 AUTH_KEYBOARD_INTERACTIVE
6252 AUTH_TYPE_PUBLICKEY
,
6253 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
6254 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
6256 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
6257 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6259 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
6260 int tried_pubkey_config
, tried_agent
;
6261 int kbd_inter_running
, kbd_inter_refused
;
6263 int num_prompts
, curr_prompt
, echo
;
6268 void *publickey_blob
;
6269 int publickey_bloblen
;
6270 unsigned char request
[5], *response
, *p
;
6274 char *pkblob
, *alg
, *commentp
;
6275 int pklen
, alglen
, commentlen
;
6276 int siglen
, retlen
, len
;
6277 char *q
, *agentreq
, *ret
;
6279 int num_env
, env_left
, env_ok
;
6280 struct Packet
*pktout
;
6282 crState(do_ssh2_authconn_state
);
6284 crBegin(ssh
->do_ssh2_authconn_crstate
);
6287 * Request userauth protocol, and await a response to it.
6289 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6290 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6291 ssh2_pkt_send(ssh
, s
->pktout
);
6292 crWaitUntilV(pktin
);
6293 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6294 bombout(("Server refused user authentication protocol"));
6299 * We repeat this whole loop, including the username prompt,
6300 * until we manage a successful authentication. If the user
6301 * types the wrong _password_, they can be sent back to the
6302 * beginning to try another username, if this is configured on.
6303 * (If they specify a username in the config, they are never
6304 * asked, even if they do give a wrong password.)
6306 * I think this best serves the needs of
6308 * - the people who have no configuration, no keys, and just
6309 * want to try repeated (username,password) pairs until they
6310 * type both correctly
6312 * - people who have keys and configuration but occasionally
6313 * need to fall back to passwords
6315 * - people with a key held in Pageant, who might not have
6316 * logged in to a particular machine before; so they want to
6317 * type a username, and then _either_ their key will be
6318 * accepted, _or_ they will type a password. If they mistype
6319 * the username they will want to be able to get back and
6322 s
->username
[0] = '\0';
6323 s
->got_username
= FALSE
;
6328 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6330 * We got a username last time round this loop, and
6331 * with change_username turned off we don't try to get
6334 } else if (!*ssh
->cfg
.username
) {
6335 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6336 if (!ssh_get_line("login as: ",
6337 s
->username
, sizeof(s
->username
), FALSE
)) {
6339 * get_line failed to get a username.
6342 logevent("No username provided. Abandoning session.");
6343 ssh
->close_expected
= TRUE
;
6344 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6348 int ret
; /* need not be saved across crReturn */
6349 c_write_str(ssh
, "login as: ");
6351 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6353 crWaitUntilV(!pktin
);
6354 ret
= process_userpass_input(ssh
, in
, inlen
);
6358 c_write_str(ssh
, "\r\n");
6360 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6363 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6364 s
->username
[sizeof(s
->username
)-1] = '\0';
6365 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6366 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6367 c_write_str(ssh
, stuff
);
6371 s
->got_username
= TRUE
;
6374 * Send an authentication request using method "none": (a)
6375 * just in case it succeeds, and (b) so that we know what
6376 * authentication methods we can usefully try next.
6378 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6380 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6381 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6382 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6383 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6384 ssh2_pkt_send(ssh
, s
->pktout
);
6385 s
->type
= AUTH_TYPE_NONE
;
6387 s
->we_are_in
= FALSE
;
6389 s
->tried_pubkey_config
= FALSE
;
6390 s
->tried_agent
= FALSE
;
6391 s
->kbd_inter_running
= FALSE
;
6392 s
->kbd_inter_refused
= FALSE
;
6393 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6394 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6396 logeventf(ssh
, "Reading private key file \"%.150s\"",
6397 filename_to_str(&ssh
->cfg
.keyfile
));
6398 keytype
= key_type(&ssh
->cfg
.keyfile
);
6399 if (keytype
== SSH_KEYTYPE_SSH2
) {
6401 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6402 &s
->publickey_bloblen
, NULL
);
6405 logeventf(ssh
, "Unable to use this key file (%s)",
6406 key_type_to_str(keytype
));
6407 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6409 filename_to_str(&ssh
->cfg
.keyfile
),
6410 key_type_to_str(keytype
));
6411 c_write_str(ssh
, msgbuf
);
6413 s
->publickey_blob
= NULL
;
6416 s
->publickey_blob
= NULL
;
6420 * Wait for the result of the last authentication request.
6423 crWaitUntilV(pktin
);
6424 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6428 * Don't show the banner if we're operating in
6429 * non-verbose non-interactive mode. (It's probably
6430 * a script, which means nobody will read the
6431 * banner _anyway_, and moreover the printing of
6432 * the banner will screw up processing on the
6433 * output of (say) plink.)
6435 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6436 ssh_pkt_getstring(pktin
, &banner
, &size
);
6438 c_write_untrusted(ssh
, banner
, size
);
6440 crWaitUntilV(pktin
);
6442 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6443 logevent("Access granted");
6444 s
->we_are_in
= TRUE
;
6448 if (s
->kbd_inter_running
&&
6449 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6451 * This is either a further set-of-prompts packet
6452 * in keyboard-interactive authentication, or it's
6453 * the same one and we came back here with `gotit'
6454 * set. In the former case, we must reset the
6455 * curr_prompt variable.
6459 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6460 /* FIXME: perhaps we should support this? */
6461 bombout(("PASSWD_CHANGEREQ not yet supported"));
6463 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6464 bombout(("Strange packet received during authentication: type %d",
6472 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6473 * we can look at the string in it and know what we can
6474 * helpfully try next.
6476 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6479 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6480 s
->kbd_inter_running
= FALSE
;
6481 if (!ssh2_pkt_getbool(pktin
)) {
6483 * We have received an unequivocal Access
6484 * Denied. This can translate to a variety of
6487 * - if we'd just tried "none" authentication,
6488 * it's not worth printing anything at all
6490 * - if we'd just tried a public key _offer_,
6491 * the message should be "Server refused our
6492 * key" (or no message at all if the key
6493 * came from Pageant)
6495 * - if we'd just tried anything else, the
6496 * message really should be "Access denied".
6498 * Additionally, if we'd just tried password
6499 * authentication, we should break out of this
6500 * whole loop so as to go back to the username
6501 * prompt (iff we're configured to allow
6502 * username change attempts).
6504 if (s
->type
== AUTH_TYPE_NONE
) {
6506 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6507 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6508 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6509 c_write_str(ssh
, "Server refused our key\r\n");
6510 logevent("Server refused public key");
6511 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6512 /* server declined keyboard-interactive; ignore */
6514 c_write_str(ssh
, "Access denied\r\n");
6515 logevent("Access denied");
6516 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6517 ssh
->cfg
.change_username
) {
6518 /* XXX perhaps we should allow
6519 * keyboard-interactive to do this too? */
6520 s
->we_are_in
= FALSE
;
6525 c_write_str(ssh
, "Further authentication required\r\n");
6526 logevent("Further authentication required");
6530 in_commasep_string("publickey", methods
, methlen
);
6532 in_commasep_string("password", methods
, methlen
);
6533 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6534 in_commasep_string("keyboard-interactive", methods
, methlen
);
6538 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6542 * Most password/passphrase prompts will be
6543 * non-echoing, so we set this to 0 by default.
6544 * Exception is that some keyboard-interactive prompts
6545 * can be echoing, in which case we'll set this to 1.
6549 if (!s
->method
&& s
->can_pubkey
&&
6550 agent_exists() && !s
->tried_agent
) {
6552 * Attempt public-key authentication using Pageant.
6557 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6558 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6560 s
->tried_agent
= TRUE
;
6562 logevent("Pageant is running. Requesting keys.");
6564 /* Request the keys held by the agent. */
6565 PUT_32BIT(s
->request
, 1);
6566 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6567 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6568 ssh_agent_callback
, ssh
)) {
6572 bombout(("Unexpected data from server while"
6573 " waiting for agent response"));
6576 } while (pktin
|| inlen
> 0);
6577 r
= ssh
->agent_response
;
6578 s
->responselen
= ssh
->agent_response_len
;
6580 s
->response
= (unsigned char *) r
;
6581 if (s
->response
&& s
->responselen
>= 5 &&
6582 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6583 s
->p
= s
->response
+ 5;
6584 s
->nkeys
= GET_32BIT(s
->p
);
6586 logeventf(ssh
, "Pageant has %d SSH2 keys", s
->nkeys
);
6587 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6590 logeventf(ssh
, "Trying Pageant key #%d", s
->keyi
);
6591 s
->pklen
= GET_32BIT(s
->p
);
6593 if (s
->publickey_blob
&&
6594 s
->pklen
== s
->publickey_bloblen
&&
6595 !memcmp(s
->p
, s
->publickey_blob
,
6596 s
->publickey_bloblen
)) {
6597 logevent("This key matches configured key file");
6598 s
->tried_pubkey_config
= 1;
6600 s
->pkblob
= (char *)s
->p
;
6602 s
->alglen
= GET_32BIT(s
->pkblob
);
6603 s
->alg
= s
->pkblob
+ 4;
6604 s
->commentlen
= GET_32BIT(s
->p
);
6606 s
->commentp
= (char *)s
->p
;
6607 s
->p
+= s
->commentlen
;
6608 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6609 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6610 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6611 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6612 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6613 ssh2_pkt_addstring_start(s
->pktout
);
6614 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6615 ssh2_pkt_addstring_start(s
->pktout
);
6616 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6617 ssh2_pkt_send(ssh
, s
->pktout
);
6619 crWaitUntilV(pktin
);
6620 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6621 logevent("Key refused");
6625 if (flags
& FLAG_VERBOSE
) {
6626 c_write_str(ssh
, "Authenticating with "
6628 c_write(ssh
, s
->commentp
, s
->commentlen
);
6629 c_write_str(ssh
, "\" from agent\r\n");
6633 * Server is willing to accept the key.
6634 * Construct a SIGN_REQUEST.
6636 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6637 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6638 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6639 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6640 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6641 ssh2_pkt_addstring_start(s
->pktout
);
6642 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6643 ssh2_pkt_addstring_start(s
->pktout
);
6644 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6646 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6647 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6649 s
->len
= 1; /* message type */
6650 s
->len
+= 4 + s
->pklen
; /* key blob */
6651 s
->len
+= 4 + s
->siglen
; /* data to sign */
6652 s
->len
+= 4; /* flags */
6653 s
->agentreq
= snewn(4 + s
->len
, char);
6654 PUT_32BIT(s
->agentreq
, s
->len
);
6655 s
->q
= s
->agentreq
+ 4;
6656 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6657 PUT_32BIT(s
->q
, s
->pklen
);
6659 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6661 PUT_32BIT(s
->q
, s
->siglen
);
6663 /* Now the data to be signed... */
6664 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6665 PUT_32BIT(s
->q
, 20);
6668 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6670 memcpy(s
->q
, s
->pktout
->data
+ 5,
6671 s
->pktout
->length
- 5);
6672 s
->q
+= s
->pktout
->length
- 5;
6673 /* And finally the (zero) flags word. */
6675 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6677 ssh_agent_callback
, ssh
)) {
6681 bombout(("Unexpected data from server"
6682 " while waiting for agent"
6686 } while (pktin
|| inlen
> 0);
6687 vret
= ssh
->agent_response
;
6688 s
->retlen
= ssh
->agent_response_len
;
6693 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6694 logevent("Sending Pageant's response");
6695 ssh2_add_sigblob(ssh
, s
->pktout
,
6696 s
->pkblob
, s
->pklen
,
6698 GET_32BIT(s
->ret
+ 5));
6699 ssh2_pkt_send(ssh
, s
->pktout
);
6704 ("Pageant failed to answer challenge");
6715 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6716 && !s
->tried_pubkey_config
) {
6717 unsigned char *pub_blob
;
6718 char *algorithm
, *comment
;
6721 s
->tried_pubkey_config
= TRUE
;
6723 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6724 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6727 * Try the public key supplied in the configuration.
6729 * First, offer the public blob to see if the server is
6730 * willing to accept it.
6733 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6738 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6739 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6740 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6741 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6742 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6743 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6744 ssh2_pkt_addstring_start(s
->pktout
);
6745 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6747 ssh2_pkt_send(ssh
, s
->pktout
);
6748 logevent("Offered public key");
6750 crWaitUntilV(pktin
);
6751 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6753 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6754 continue; /* key refused; give up on it */
6757 logevent("Offer of public key accepted");
6759 * Actually attempt a serious authentication using
6762 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6763 sprintf(s
->pwprompt
,
6764 "Passphrase for key \"%.100s\": ",
6770 if (flags
& FLAG_VERBOSE
) {
6771 c_write_str(ssh
, "Authenticating with public key \"");
6772 c_write_str(ssh
, comment
);
6773 c_write_str(ssh
, "\"\r\n");
6775 s
->method
= AUTH_PUBLICKEY_FILE
;
6779 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6780 !s
->kbd_inter_running
) {
6781 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6782 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6784 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6785 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6787 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6788 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6789 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6790 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6791 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6792 ssh2_pkt_addstring(s
->pktout
, "");
6793 ssh2_pkt_send(ssh
, s
->pktout
);
6795 crWaitUntilV(pktin
);
6796 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6797 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6799 logevent("Keyboard-interactive authentication refused");
6800 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6801 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6805 s
->kbd_inter_running
= TRUE
;
6809 if (s
->kbd_inter_running
) {
6810 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6811 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6813 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6814 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6816 if (s
->curr_prompt
== 0) {
6818 * We've got a fresh USERAUTH_INFO_REQUEST.
6819 * Display header data, and start going through
6822 char *name
, *inst
, *lang
;
6823 int name_len
, inst_len
, lang_len
;
6825 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6826 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6827 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6829 c_write_untrusted(ssh
, name
, name_len
);
6830 c_write_str(ssh
, "\r\n");
6833 c_write_untrusted(ssh
, inst
, inst_len
);
6834 c_write_str(ssh
, "\r\n");
6836 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6840 * If there are prompts remaining in the packet,
6841 * display one and get a response.
6843 if (s
->curr_prompt
< s
->num_prompts
) {
6847 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6848 if (prompt_len
> 0) {
6849 static const char trunc
[] = "<prompt truncated>: ";
6850 static const int prlen
= sizeof(s
->pwprompt
) -
6852 if (prompt_len
> prlen
) {
6853 memcpy(s
->pwprompt
, prompt
, prlen
);
6854 strcpy(s
->pwprompt
+ prlen
, trunc
);
6856 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6857 s
->pwprompt
[prompt_len
] = '\0';
6861 "<server failed to send prompt>: ");
6863 s
->echo
= ssh2_pkt_getbool(pktin
);
6869 if (!s
->method
&& s
->can_passwd
) {
6870 s
->method
= AUTH_PASSWORD
;
6871 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6872 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6873 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6880 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6881 sizeof(s
->password
), TRUE
)) {
6883 * get_line failed to get a password (for
6884 * example because one was supplied on the
6885 * command line which has already failed to
6888 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6889 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6890 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6892 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6893 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6894 logevent("Unable to authenticate");
6895 connection_fatal(ssh
->frontend
,
6896 "Unable to authenticate");
6897 ssh
->close_expected
= TRUE
;
6898 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6902 int ret
; /* need not be saved across crReturn */
6903 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6906 setup_userpass_input(ssh
, s
->password
,
6907 sizeof(s
->password
), s
->echo
);
6909 crWaitUntilV(!pktin
);
6910 ret
= process_userpass_input(ssh
, in
, inlen
);
6914 c_write_str(ssh
, "\r\n");
6918 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6920 * We have our passphrase. Now try the actual authentication.
6922 struct ssh2_userkey
*key
;
6923 const char *error
= NULL
;
6925 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6927 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6928 if (key
== SSH2_WRONG_PASSPHRASE
) {
6929 c_write_str(ssh
, "Wrong passphrase\r\n");
6930 s
->tried_pubkey_config
= FALSE
;
6932 c_write_str(ssh
, "Unable to load private key (");
6933 c_write_str(ssh
, error
);
6934 c_write_str(ssh
, ")\r\n");
6935 s
->tried_pubkey_config
= TRUE
;
6937 /* Send a spurious AUTH_NONE to return to the top. */
6938 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6939 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6940 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6941 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6942 ssh2_pkt_send(ssh
, s
->pktout
);
6943 s
->type
= AUTH_TYPE_NONE
;
6945 unsigned char *pkblob
, *sigblob
, *sigdata
;
6946 int pkblob_len
, sigblob_len
, sigdata_len
;
6950 * We have loaded the private key and the server
6951 * has announced that it's willing to accept it.
6952 * Hallelujah. Generate a signature and send it.
6954 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6955 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6956 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6957 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6958 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6959 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6960 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6961 ssh2_pkt_addstring_start(s
->pktout
);
6962 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6965 * The data to be signed is:
6969 * followed by everything so far placed in the
6972 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6973 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6975 sigdata
= snewn(sigdata_len
, unsigned char);
6977 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6978 PUT_32BIT(sigdata
+p
, 20);
6981 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6982 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6983 s
->pktout
->length
- 5);
6984 p
+= s
->pktout
->length
- 5;
6985 assert(p
== sigdata_len
);
6986 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6987 sigdata_len
, &sigblob_len
);
6988 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6989 sigblob
, sigblob_len
);
6994 ssh2_pkt_send(ssh
, s
->pktout
);
6995 s
->type
= AUTH_TYPE_PUBLICKEY
;
6996 key
->alg
->freekey(key
->data
);
6998 } else if (s
->method
== AUTH_PASSWORD
) {
7000 * We pad out the password packet to 256 bytes to make
7001 * it harder for an attacker to find the length of the
7004 * Anyone using a password longer than 256 bytes
7005 * probably doesn't have much to worry about from
7006 * people who find out how long their password is!
7008 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
7009 s
->pktout
->forcepad
= 256;
7010 ssh2_pkt_addstring(s
->pktout
, s
->username
);
7011 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
7012 ssh2_pkt_addstring(s
->pktout
, "password");
7013 ssh2_pkt_addbool(s
->pktout
, FALSE
);
7014 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7015 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7016 memset(s
->password
, 0, sizeof(s
->password
));
7017 end_log_omission(ssh
, s
->pktout
);
7018 ssh2_pkt_send(ssh
, s
->pktout
);
7019 logevent("Sent password");
7020 s
->type
= AUTH_TYPE_PASSWORD
;
7021 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
7022 if (s
->curr_prompt
== 0) {
7023 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
7024 s
->pktout
->forcepad
= 256;
7025 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
7027 if (s
->need_pw
) { /* only add pw if we just got one! */
7028 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
7029 ssh2_pkt_addstring(s
->pktout
, s
->password
);
7030 memset(s
->password
, 0, sizeof(s
->password
));
7031 end_log_omission(ssh
, s
->pktout
);
7034 if (s
->curr_prompt
>= s
->num_prompts
) {
7035 ssh2_pkt_send(ssh
, s
->pktout
);
7038 * If there are prompts remaining, we set
7039 * `gotit' so that we won't attempt to get
7040 * another packet. Then we go back round the
7041 * loop and will end up retrieving another
7042 * prompt out of the existing packet. Funky or
7047 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
7049 c_write_str(ssh
, "No supported authentication methods"
7050 " left to try!\r\n");
7051 logevent("No supported authentications offered."
7053 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
7054 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
7055 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
7056 " methods available");
7057 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
7058 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
7059 ssh
->close_expected
= TRUE
;
7060 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
7064 } while (!s
->we_are_in
);
7067 * Now we're authenticated for the connection protocol. The
7068 * connection protocol will automatically have started at this
7069 * point; there's no need to send SERVICE_REQUEST.
7072 ssh
->channels
= newtree234(ssh_channelcmp
);
7075 * Set up handlers for some connection protocol messages, so we
7076 * don't have to handle them repeatedly in this coroutine.
7078 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
7079 ssh2_msg_channel_window_adjust
;
7080 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
7081 ssh2_msg_global_request
;
7084 * Create the main session channel.
7086 if (!ssh
->cfg
.ssh_no_shell
) {
7087 ssh
->mainchan
= snew(struct ssh_channel
);
7088 ssh
->mainchan
->ssh
= ssh
;
7089 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
7090 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7091 ssh2_pkt_addstring(s
->pktout
, "session");
7092 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
7093 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7094 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
7095 ssh2_pkt_adduint32(s
->pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
7096 ssh2_pkt_send(ssh
, s
->pktout
);
7097 crWaitUntilV(pktin
);
7098 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
7099 bombout(("Server refused to open a session"));
7101 /* FIXME: error data comes back in FAILURE packet */
7103 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
7104 bombout(("Server's channel confirmation cited wrong channel"));
7107 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
7108 ssh
->mainchan
->halfopen
= FALSE
;
7109 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
7110 ssh
->mainchan
->closes
= 0;
7111 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
7112 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
7113 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
7114 add234(ssh
->channels
, ssh
->mainchan
);
7115 update_specials_menu(ssh
->frontend
);
7116 logevent("Opened channel for session");
7118 ssh
->mainchan
= NULL
;
7121 * Now we have a channel, make dispatch table entries for
7122 * general channel-based messages.
7124 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
7125 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
7126 ssh2_msg_channel_data
;
7127 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
7128 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
7129 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
7130 ssh2_msg_channel_open_confirmation
;
7131 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
7132 ssh2_msg_channel_open_failure
;
7133 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
7134 ssh2_msg_channel_request
;
7135 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
7136 ssh2_msg_channel_open
;
7139 * Potentially enable X11 forwarding.
7141 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
7142 char proto
[20], data
[64];
7143 logevent("Requesting X11 forwarding");
7144 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
7145 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
7146 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
7147 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7148 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7149 ssh2_pkt_addstring(s
->pktout
, "x11-req");
7150 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7151 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
7152 ssh2_pkt_addstring(s
->pktout
, proto
);
7153 ssh2_pkt_addstring(s
->pktout
, data
);
7154 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
7155 ssh2_pkt_send(ssh
, s
->pktout
);
7157 crWaitUntilV(pktin
);
7159 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7160 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7161 bombout(("Unexpected response to X11 forwarding request:"
7162 " packet type %d", pktin
->type
));
7165 logevent("X11 forwarding refused");
7167 logevent("X11 forwarding enabled");
7168 ssh
->X11_fwd_enabled
= TRUE
;
7173 * Enable port forwardings.
7175 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
7178 * Potentially enable agent forwarding.
7180 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
7181 logevent("Requesting OpenSSH-style agent forwarding");
7182 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7183 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7184 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
7185 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7186 ssh2_pkt_send(ssh
, s
->pktout
);
7188 crWaitUntilV(pktin
);
7190 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7191 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7192 bombout(("Unexpected response to agent forwarding request:"
7193 " packet type %d", pktin
->type
));
7196 logevent("Agent forwarding refused");
7198 logevent("Agent forwarding enabled");
7199 ssh
->agentfwd_enabled
= TRUE
;
7204 * Now allocate a pty for the session.
7206 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
7207 /* Unpick the terminal-speed string. */
7208 /* XXX perhaps we should allow no speeds to be sent. */
7209 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
7210 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
7211 /* Build the pty request. */
7212 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7213 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7214 ssh2_pkt_addstring(s
->pktout
, "pty-req");
7215 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7216 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
7217 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
7218 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
7219 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
7220 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
7221 ssh2_pkt_addstring_start(s
->pktout
);
7222 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
7223 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
7224 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
7225 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
7226 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
7227 ssh2_pkt_send(ssh
, s
->pktout
);
7228 ssh
->state
= SSH_STATE_INTERMED
;
7230 crWaitUntilV(pktin
);
7232 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7233 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7234 bombout(("Unexpected response to pty request:"
7235 " packet type %d", pktin
->type
));
7238 c_write_str(ssh
, "Server refused to allocate pty\r\n");
7239 ssh
->editing
= ssh
->echoing
= 1;
7241 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
7242 ssh
->ospeed
, ssh
->ispeed
);
7245 ssh
->editing
= ssh
->echoing
= 1;
7249 * Send environment variables.
7251 * Simplest thing here is to send all the requests at once, and
7252 * then wait for a whole bunch of successes or failures.
7254 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7255 char *e
= ssh
->cfg
.environmt
;
7256 char *var
, *varend
, *val
;
7262 while (*e
&& *e
!= '\t') e
++;
7264 if (*e
== '\t') e
++;
7269 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7270 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7271 ssh2_pkt_addstring(s
->pktout
, "env");
7272 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7273 ssh2_pkt_addstring_start(s
->pktout
);
7274 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7275 ssh2_pkt_addstring(s
->pktout
, val
);
7276 ssh2_pkt_send(ssh
, s
->pktout
);
7281 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7284 s
->env_left
= s
->num_env
;
7286 while (s
->env_left
> 0) {
7287 crWaitUntilV(pktin
);
7289 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7290 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7291 bombout(("Unexpected response to environment request:"
7292 " packet type %d", pktin
->type
));
7302 if (s
->env_ok
== s
->num_env
) {
7303 logevent("All environment variables successfully set");
7304 } else if (s
->env_ok
== 0) {
7305 logevent("All environment variables refused");
7306 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7308 logeventf(ssh
, "%d environment variables refused",
7309 s
->num_env
- s
->env_ok
);
7310 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7315 * Start a shell or a remote command. We may have to attempt
7316 * this twice if the config data has provided a second choice
7319 if (ssh
->mainchan
) while (1) {
7323 if (ssh
->fallback_cmd
) {
7324 subsys
= ssh
->cfg
.ssh_subsys2
;
7325 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7327 subsys
= ssh
->cfg
.ssh_subsys
;
7328 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7329 if (!cmd
) cmd
= ssh
->cfg
.remote_cmd
;
7332 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7333 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7335 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7336 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7337 ssh2_pkt_addstring(s
->pktout
, cmd
);
7339 ssh2_pkt_addstring(s
->pktout
, "exec");
7340 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7341 ssh2_pkt_addstring(s
->pktout
, cmd
);
7343 ssh2_pkt_addstring(s
->pktout
, "shell");
7344 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7346 ssh2_pkt_send(ssh
, s
->pktout
);
7348 crWaitUntilV(pktin
);
7350 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7351 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7352 bombout(("Unexpected response to shell/command request:"
7353 " packet type %d", pktin
->type
));
7357 * We failed to start the command. If this is the
7358 * fallback command, we really are finished; if it's
7359 * not, and if the fallback command exists, try falling
7360 * back to it before complaining.
7362 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7363 logevent("Primary command failed; attempting fallback");
7364 ssh
->fallback_cmd
= TRUE
;
7367 bombout(("Server refused to start a shell/command"));
7370 logevent("Started a shell/command");
7375 ssh
->state
= SSH_STATE_SESSION
;
7376 if (ssh
->size_needed
)
7377 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7378 if (ssh
->eof_needed
)
7379 ssh_special(ssh
, TS_EOF
);
7385 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7390 s
->try_send
= FALSE
;
7394 * _All_ the connection-layer packets we expect to
7395 * receive are now handled by the dispatch table.
7396 * Anything that reaches here must be bogus.
7399 bombout(("Strange packet received: type %d", pktin
->type
));
7401 } else if (ssh
->mainchan
) {
7403 * We have spare data. Add it to the channel buffer.
7405 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7410 struct ssh_channel
*c
;
7412 * Try to send data on all channels if we can.
7414 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7417 continue; /* don't send on closing channels */
7418 bufsize
= ssh2_try_send(c
);
7421 case CHAN_MAINSESSION
:
7422 /* stdin need not receive an unthrottle
7423 * notification since it will be polled */
7426 x11_unthrottle(c
->u
.x11
.s
);
7429 /* agent sockets are request/response and need no
7430 * buffer management */
7433 pfd_unthrottle(c
->u
.pfd
.s
);
7445 * Handlers for SSH2 messages that might arrive at any moment.
7447 static void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7449 /* log reason code in disconnect message */
7451 int nowlen
, reason
, msglen
;
7453 reason
= ssh_pkt_getuint32(pktin
);
7454 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7456 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7457 buf
= dupprintf("Received disconnect message (%s)",
7458 ssh2_disconnect_reasons
[reason
]);
7460 buf
= dupprintf("Received disconnect message (unknown"
7461 " type %d)", reason
);
7465 buf
= dupprintf("Disconnection message text: %n%.*s",
7466 &nowlen
, msglen
, msg
);
7468 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7470 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7471 ssh2_disconnect_reasons
[reason
] : "unknown",
7476 static void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7478 /* log the debug message */
7483 /* XXX maybe we should actually take notice of this */
7484 always_display
= ssh2_pkt_getbool(pktin
);
7485 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7487 logeventf(ssh
, "Remote debug message: %.*s", msglen
, msg
);
7490 static void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7492 struct Packet
*pktout
;
7493 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7494 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7496 * UNIMPLEMENTED messages MUST appear in the same order as the
7497 * messages they respond to. Hence, never queue them.
7499 ssh2_pkt_send_noqueue(ssh
, pktout
);
7503 * Handle the top-level SSH2 protocol.
7505 static void ssh2_protocol_setup(Ssh ssh
)
7510 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7512 for (i
= 0; i
< 256; i
++)
7513 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7516 * Any message we actually understand, we set to NULL so that
7517 * the coroutines will get it.
7519 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7520 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7521 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7522 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7523 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7524 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7525 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7526 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7527 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7528 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7529 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7530 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7531 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7532 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7533 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7534 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7535 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7536 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7537 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7538 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7539 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7540 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7541 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7542 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7543 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7544 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7545 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7546 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7547 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7548 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7549 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7550 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7551 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7554 * These special message types we install handlers for.
7556 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7557 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7558 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7561 static void ssh2_timer(void *ctx
, long now
)
7565 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7566 now
- ssh
->next_rekey
>= 0) {
7567 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7571 static void ssh2_protocol(Ssh ssh
, void *vin
, int inlen
,
7572 struct Packet
*pktin
)
7574 unsigned char *in
= (unsigned char *)vin
;
7575 if (ssh
->state
== SSH_STATE_CLOSED
)
7579 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7580 if (!ssh
->kex_in_progress
&&
7581 ssh
->max_data_size
!= 0 &&
7582 ssh
->incoming_data_size
> ssh
->max_data_size
)
7583 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7586 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7587 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7591 if (!ssh
->protocol_initial_phase_done
||
7592 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7593 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7594 !ssh
->protocol_initial_phase_done
) {
7595 ssh
->protocol_initial_phase_done
= TRUE
;
7597 * Allow authconn to initialise itself.
7599 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7602 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7607 * Called to set up the connection.
7609 * Returns an error message, or NULL on success.
7611 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7613 char *host
, int port
, char **realhost
, int nodelay
,
7619 ssh
= snew(struct ssh_tag
);
7620 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7621 ssh
->version
= 0; /* when not ready yet */
7624 ssh
->v1_cipher_ctx
= NULL
;
7625 ssh
->crcda_ctx
= NULL
;
7626 ssh
->cscipher
= NULL
;
7627 ssh
->cs_cipher_ctx
= NULL
;
7628 ssh
->sccipher
= NULL
;
7629 ssh
->sc_cipher_ctx
= NULL
;
7631 ssh
->cs_mac_ctx
= NULL
;
7633 ssh
->sc_mac_ctx
= NULL
;
7635 ssh
->cs_comp_ctx
= NULL
;
7637 ssh
->sc_comp_ctx
= NULL
;
7639 ssh
->kex_ctx
= NULL
;
7640 ssh
->hostkey
= NULL
;
7642 ssh
->close_expected
= FALSE
;
7643 ssh
->state
= SSH_STATE_PREPACKET
;
7644 ssh
->size_needed
= FALSE
;
7645 ssh
->eof_needed
= FALSE
;
7648 ssh
->deferred_send_data
= NULL
;
7649 ssh
->deferred_len
= 0;
7650 ssh
->deferred_size
= 0;
7651 ssh
->fallback_cmd
= 0;
7653 ssh
->x11auth
= NULL
;
7654 ssh
->v1_compressing
= FALSE
;
7655 ssh
->v2_outgoing_sequence
= 0;
7656 ssh
->ssh1_rdpkt_crstate
= 0;
7657 ssh
->ssh2_rdpkt_crstate
= 0;
7658 ssh
->do_ssh_init_crstate
= 0;
7659 ssh
->ssh_gotdata_crstate
= 0;
7660 ssh
->do_ssh1_connection_crstate
= 0;
7661 ssh
->do_ssh1_login_crstate
= 0;
7662 ssh
->do_ssh2_transport_crstate
= 0;
7663 ssh
->do_ssh2_authconn_crstate
= 0;
7664 ssh
->do_ssh_init_state
= NULL
;
7665 ssh
->do_ssh1_login_state
= NULL
;
7666 ssh
->do_ssh2_transport_state
= NULL
;
7667 ssh
->do_ssh2_authconn_state
= NULL
;
7668 ssh
->mainchan
= NULL
;
7669 ssh
->throttled_all
= 0;
7670 ssh
->v1_stdout_throttling
= 0;
7672 ssh
->queuelen
= ssh
->queuesize
= 0;
7673 ssh
->queueing
= FALSE
;
7674 ssh
->qhead
= ssh
->qtail
= NULL
;
7675 ssh
->deferred_rekey_reason
= NULL
;
7676 bufchain_init(&ssh
->queued_incoming_data
);
7677 ssh
->frozen
= FALSE
;
7679 *backend_handle
= ssh
;
7682 if (crypto_startup() == 0)
7683 return "Microsoft high encryption pack not installed!";
7686 ssh
->frontend
= frontend_handle
;
7687 ssh
->term_width
= ssh
->cfg
.width
;
7688 ssh
->term_height
= ssh
->cfg
.height
;
7690 ssh
->channels
= NULL
;
7691 ssh
->rportfwds
= NULL
;
7692 ssh
->portfwds
= NULL
;
7697 ssh
->v1_throttle_count
= 0;
7698 ssh
->overall_bufsize
= 0;
7699 ssh
->fallback_cmd
= 0;
7701 ssh
->protocol
= NULL
;
7703 ssh
->protocol_initial_phase_done
= FALSE
;
7707 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7708 ssh
->deferred_data_size
= 0L;
7709 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7710 ssh
->kex_in_progress
= FALSE
;
7712 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7721 static void ssh_free(void *handle
)
7723 Ssh ssh
= (Ssh
) handle
;
7724 struct ssh_channel
*c
;
7725 struct ssh_rportfwd
*pf
;
7727 if (ssh
->v1_cipher_ctx
)
7728 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7729 if (ssh
->cs_cipher_ctx
)
7730 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7731 if (ssh
->sc_cipher_ctx
)
7732 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7733 if (ssh
->cs_mac_ctx
)
7734 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7735 if (ssh
->sc_mac_ctx
)
7736 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7737 if (ssh
->cs_comp_ctx
) {
7739 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7741 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7743 if (ssh
->sc_comp_ctx
) {
7745 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7747 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7750 dh_cleanup(ssh
->kex_ctx
);
7751 sfree(ssh
->savedhost
);
7753 while (ssh
->queuelen
-- > 0)
7754 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7757 while (ssh
->qhead
) {
7758 struct queued_handler
*qh
= ssh
->qhead
;
7759 ssh
->qhead
= qh
->next
;
7762 ssh
->qhead
= ssh
->qtail
= NULL
;
7764 if (ssh
->channels
) {
7765 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7768 if (c
->u
.x11
.s
!= NULL
)
7769 x11_close(c
->u
.x11
.s
);
7772 if (c
->u
.pfd
.s
!= NULL
)
7773 pfd_close(c
->u
.pfd
.s
);
7778 freetree234(ssh
->channels
);
7779 ssh
->channels
= NULL
;
7782 if (ssh
->rportfwds
) {
7783 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7785 freetree234(ssh
->rportfwds
);
7786 ssh
->rportfwds
= NULL
;
7788 sfree(ssh
->deferred_send_data
);
7790 x11_free_auth(ssh
->x11auth
);
7791 sfree(ssh
->do_ssh_init_state
);
7792 sfree(ssh
->do_ssh1_login_state
);
7793 sfree(ssh
->do_ssh2_transport_state
);
7794 sfree(ssh
->do_ssh2_authconn_state
);
7795 if (ssh
->crcda_ctx
) {
7796 crcda_free_context(ssh
->crcda_ctx
);
7797 ssh
->crcda_ctx
= NULL
;
7800 ssh_do_close(ssh
, TRUE
);
7801 expire_timer_context(ssh
);
7803 pinger_free(ssh
->pinger
);
7804 bufchain_clear(&ssh
->queued_incoming_data
);
7811 * Reconfigure the SSH backend.
7813 static void ssh_reconfig(void *handle
, Config
*cfg
)
7815 Ssh ssh
= (Ssh
) handle
;
7816 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7817 unsigned long old_max_data_size
;
7819 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7820 ssh_setup_portfwd(ssh
, cfg
);
7822 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7823 cfg
->ssh_rekey_time
!= 0) {
7824 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7825 long now
= GETTICKCOUNT();
7827 if (new_next
- now
< 0) {
7828 rekeying
= "timeout shortened";
7830 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7834 old_max_data_size
= ssh
->max_data_size
;
7835 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7836 if (old_max_data_size
!= ssh
->max_data_size
&&
7837 ssh
->max_data_size
!= 0) {
7838 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7839 ssh
->incoming_data_size
> ssh
->max_data_size
)
7840 rekeying
= "data limit lowered";
7843 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7844 rekeying
= "compression setting changed";
7845 rekey_mandatory
= TRUE
;
7848 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7849 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7850 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7851 rekeying
= "cipher settings changed";
7852 rekey_mandatory
= TRUE
;
7855 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7858 if (!ssh
->kex_in_progress
) {
7859 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7860 } else if (rekey_mandatory
) {
7861 ssh
->deferred_rekey_reason
= rekeying
;
7867 * Called to send data down the Telnet connection.
7869 static int ssh_send(void *handle
, char *buf
, int len
)
7871 Ssh ssh
= (Ssh
) handle
;
7873 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7876 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7878 return ssh_sendbuffer(ssh
);
7882 * Called to query the current amount of buffered stdin data.
7884 static int ssh_sendbuffer(void *handle
)
7886 Ssh ssh
= (Ssh
) handle
;
7889 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7893 * If the SSH socket itself has backed up, add the total backup
7894 * size on that to any individual buffer on the stdin channel.
7897 if (ssh
->throttled_all
)
7898 override_value
= ssh
->overall_bufsize
;
7900 if (ssh
->version
== 1) {
7901 return override_value
;
7902 } else if (ssh
->version
== 2) {
7903 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7904 return override_value
;
7906 return (override_value
+
7907 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7914 * Called to set the size of the window from SSH's POV.
7916 static void ssh_size(void *handle
, int width
, int height
)
7918 Ssh ssh
= (Ssh
) handle
;
7919 struct Packet
*pktout
;
7921 ssh
->term_width
= width
;
7922 ssh
->term_height
= height
;
7924 switch (ssh
->state
) {
7925 case SSH_STATE_BEFORE_SIZE
:
7926 case SSH_STATE_PREPACKET
:
7927 case SSH_STATE_CLOSED
:
7928 break; /* do nothing */
7929 case SSH_STATE_INTERMED
:
7930 ssh
->size_needed
= TRUE
; /* buffer for later */
7932 case SSH_STATE_SESSION
:
7933 if (!ssh
->cfg
.nopty
) {
7934 if (ssh
->version
== 1) {
7935 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7936 PKT_INT
, ssh
->term_height
,
7937 PKT_INT
, ssh
->term_width
,
7938 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7939 } else if (ssh
->mainchan
) {
7940 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7941 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7942 ssh2_pkt_addstring(pktout
, "window-change");
7943 ssh2_pkt_addbool(pktout
, 0);
7944 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7945 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7946 ssh2_pkt_adduint32(pktout
, 0);
7947 ssh2_pkt_adduint32(pktout
, 0);
7948 ssh2_pkt_send(ssh
, pktout
);
7956 * Return a list of the special codes that make sense in this
7959 static const struct telnet_special
*ssh_get_specials(void *handle
)
7961 static const struct telnet_special ssh1_ignore_special
[] = {
7962 {"IGNORE message", TS_NOP
}
7964 static const struct telnet_special ssh2_transport_specials
[] = {
7965 {"IGNORE message", TS_NOP
},
7966 {"Repeat key exchange", TS_REKEY
},
7968 static const struct telnet_special ssh2_session_specials
[] = {
7971 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7972 * They include all the ISO C signals, but are a subset of the POSIX
7973 * required signals. */
7974 {"SIGINT (Interrupt)", TS_SIGINT
},
7975 {"SIGTERM (Terminate)", TS_SIGTERM
},
7976 {"SIGKILL (Kill)", TS_SIGKILL
},
7977 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7978 {"SIGHUP (Hangup)", TS_SIGHUP
},
7979 {"More signals", TS_SUBMENU
},
7980 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7981 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7982 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7983 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7986 static const struct telnet_special specials_end
[] = {
7989 /* XXX review this length for any changes: */
7990 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7991 lenof(ssh2_session_specials
) +
7992 lenof(specials_end
)];
7993 Ssh ssh
= (Ssh
) handle
;
7995 #define ADD_SPECIALS(name) \
7997 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7998 memcpy(&ssh_specials[i], name, sizeof name); \
8002 if (ssh
->version
== 1) {
8003 /* Don't bother offering IGNORE if we've decided the remote
8004 * won't cope with it, since we wouldn't bother sending it if
8006 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8007 ADD_SPECIALS(ssh1_ignore_special
);
8008 } else if (ssh
->version
== 2) {
8009 ADD_SPECIALS(ssh2_transport_specials
);
8011 ADD_SPECIALS(ssh2_session_specials
);
8012 } /* else we're not ready yet */
8015 ADD_SPECIALS(specials_end
);
8016 return ssh_specials
;
8024 * Send Telnet special codes. TS_EOF is useful for `plink', so you
8025 * can send an EOF and collect resulting output (e.g. `plink
8028 static void ssh_special(void *handle
, Telnet_Special code
)
8030 Ssh ssh
= (Ssh
) handle
;
8031 struct Packet
*pktout
;
8033 if (code
== TS_EOF
) {
8034 if (ssh
->state
!= SSH_STATE_SESSION
) {
8036 * Buffer the EOF in case we are pre-SESSION, so we can
8037 * send it as soon as we reach SESSION.
8040 ssh
->eof_needed
= TRUE
;
8043 if (ssh
->version
== 1) {
8044 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
8045 } else if (ssh
->mainchan
) {
8046 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
8047 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8048 ssh2_pkt_send(ssh
, pktout
);
8050 logevent("Sent EOF message");
8051 } else if (code
== TS_PING
|| code
== TS_NOP
) {
8052 if (ssh
->state
== SSH_STATE_CLOSED
8053 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8054 if (ssh
->version
== 1) {
8055 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
8056 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
8058 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
8059 ssh2_pkt_addstring_start(pktout
);
8060 ssh2_pkt_send_noqueue(ssh
, pktout
);
8062 } else if (code
== TS_REKEY
) {
8063 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
8064 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
8066 } else if (code
== TS_BRK
) {
8067 if (ssh
->state
== SSH_STATE_CLOSED
8068 || ssh
->state
== SSH_STATE_PREPACKET
) return;
8069 if (ssh
->version
== 1) {
8070 logevent("Unable to send BREAK signal in SSH1");
8071 } else if (ssh
->mainchan
) {
8072 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8073 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8074 ssh2_pkt_addstring(pktout
, "break");
8075 ssh2_pkt_addbool(pktout
, 0);
8076 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
8077 ssh2_pkt_send(ssh
, pktout
);
8080 /* Is is a POSIX signal? */
8081 char *signame
= NULL
;
8082 if (code
== TS_SIGABRT
) signame
= "ABRT";
8083 if (code
== TS_SIGALRM
) signame
= "ALRM";
8084 if (code
== TS_SIGFPE
) signame
= "FPE";
8085 if (code
== TS_SIGHUP
) signame
= "HUP";
8086 if (code
== TS_SIGILL
) signame
= "ILL";
8087 if (code
== TS_SIGINT
) signame
= "INT";
8088 if (code
== TS_SIGKILL
) signame
= "KILL";
8089 if (code
== TS_SIGPIPE
) signame
= "PIPE";
8090 if (code
== TS_SIGQUIT
) signame
= "QUIT";
8091 if (code
== TS_SIGSEGV
) signame
= "SEGV";
8092 if (code
== TS_SIGTERM
) signame
= "TERM";
8093 if (code
== TS_SIGUSR1
) signame
= "USR1";
8094 if (code
== TS_SIGUSR2
) signame
= "USR2";
8095 /* The SSH-2 protocol does in principle support arbitrary named
8096 * signals, including signame@domain, but we don't support those. */
8098 /* It's a signal. */
8099 if (ssh
->version
== 2 && ssh
->mainchan
) {
8100 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
8101 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
8102 ssh2_pkt_addstring(pktout
, "signal");
8103 ssh2_pkt_addbool(pktout
, 0);
8104 ssh2_pkt_addstring(pktout
, signame
);
8105 ssh2_pkt_send(ssh
, pktout
);
8106 logeventf(ssh
, "Sent signal SIG%s", signame
);
8109 /* Never heard of it. Do nothing */
8114 void *new_sock_channel(void *handle
, Socket s
)
8116 Ssh ssh
= (Ssh
) handle
;
8117 struct ssh_channel
*c
;
8118 c
= snew(struct ssh_channel
);
8123 c
->localid
= alloc_channel_id(ssh
);
8125 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
8127 bufchain_init(&c
->v
.v2
.outbuffer
);
8128 add234(ssh
->channels
, c
);
8134 * This is called when stdout/stderr (the entity to which
8135 * from_backend sends data) manages to clear some backlog.
8137 static void ssh_unthrottle(void *handle
, int bufsize
)
8139 Ssh ssh
= (Ssh
) handle
;
8140 if (ssh
->version
== 1) {
8141 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
8142 ssh
->v1_stdout_throttling
= 0;
8143 ssh1_throttle(ssh
, -1);
8146 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
8147 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
8151 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
8153 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
8155 struct Packet
*pktout
;
8157 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
8159 if (ssh
->version
== 1) {
8160 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
8161 PKT_INT
, c
->localid
,
8164 /* PKT_STR, <org:orgport>, */
8167 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
8168 ssh2_pkt_addstring(pktout
, "direct-tcpip");
8169 ssh2_pkt_adduint32(pktout
, c
->localid
);
8170 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
8171 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
8172 ssh2_pkt_adduint32(pktout
, OUR_V2_MAXPKT
); /* our max pkt size */
8173 ssh2_pkt_addstring(pktout
, hostname
);
8174 ssh2_pkt_adduint32(pktout
, port
);
8176 * We make up values for the originator data; partly it's
8177 * too much hassle to keep track, and partly I'm not
8178 * convinced the server should be told details like that
8179 * about my local network configuration.
8181 ssh2_pkt_addstring(pktout
, "client-side-connection");
8182 ssh2_pkt_adduint32(pktout
, 0);
8183 ssh2_pkt_send(ssh
, pktout
);
8187 static Socket
ssh_socket(void *handle
)
8189 Ssh ssh
= (Ssh
) handle
;
8193 static int ssh_sendok(void *handle
)
8195 Ssh ssh
= (Ssh
) handle
;
8196 return ssh
->send_ok
;
8199 static int ssh_ldisc(void *handle
, int option
)
8201 Ssh ssh
= (Ssh
) handle
;
8202 if (option
== LD_ECHO
)
8203 return ssh
->echoing
;
8204 if (option
== LD_EDIT
)
8205 return ssh
->editing
;
8209 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
8211 Ssh ssh
= (Ssh
) handle
;
8215 static void ssh_provide_logctx(void *handle
, void *logctx
)
8217 Ssh ssh
= (Ssh
) handle
;
8218 ssh
->logctx
= logctx
;
8221 static int ssh_return_exitcode(void *handle
)
8223 Ssh ssh
= (Ssh
) handle
;
8227 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
8231 * cfg_info for SSH is the currently running version of the
8232 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8234 static int ssh_cfg_info(void *handle
)
8236 Ssh ssh
= (Ssh
) handle
;
8237 return ssh
->version
;
8241 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8242 * that fails. This variable is the means by which scp.c can reach
8243 * into the SSH code and find out which one it got.
8245 extern int ssh_fallback_cmd(void *handle
)
8247 Ssh ssh
= (Ssh
) handle
;
8248 return ssh
->fallback_cmd
;
8251 Backend ssh_backend
= {
8261 ssh_return_exitcode
,