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
364 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
366 static void *nullmac_make_context(void)
370 static void nullmac_free_context(void *handle
)
373 static void nullmac_key(void *handle
, unsigned char *key
)
376 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
380 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
385 const static struct ssh_mac ssh_mac_none
= {
386 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
387 nullmac_generate
, nullmac_verify
, "none", 0
389 const static struct ssh_mac
*macs
[] = {
390 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
392 const static struct ssh_mac
*buggymacs
[] = {
393 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
396 static void *ssh_comp_none_init(void)
400 static void ssh_comp_none_cleanup(void *handle
)
403 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
404 unsigned char **outblock
, int *outlen
)
408 static int ssh_comp_none_disable(void *handle
)
412 const static struct ssh_compress ssh_comp_none
= {
414 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
415 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
416 ssh_comp_none_disable
, NULL
418 extern const struct ssh_compress ssh_zlib
;
419 const static struct ssh_compress
*compressions
[] = {
420 &ssh_zlib
, &ssh_comp_none
423 enum { /* channel types */
428 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
432 * 2-3-4 tree storing channels.
435 Ssh ssh
; /* pointer back to main context */
436 unsigned remoteid
, localid
;
439 * In SSH1, this value contains four bits:
441 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
442 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
443 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
444 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * A channel is completely finished with when all four bits are set.
450 struct ssh1_data_channel
{
453 struct ssh2_data_channel
{
455 unsigned remwindow
, remmaxpkt
;
460 struct ssh_agent_channel
{
461 unsigned char *message
;
462 unsigned char msglen
[4];
463 unsigned lensofar
, totallen
;
465 struct ssh_x11_channel
{
468 struct ssh_pfd_channel
{
475 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
476 * 2 use this structure in different ways, reflecting SSH 2's
477 * altogether saner approach to port forwarding.
479 * In SSH 1, you arrange a remote forwarding by sending the server
480 * the remote port number, and the local destination host:port.
481 * When a connection comes in, the server sends you back that
482 * host:port pair, and you connect to it. This is a ready-made
483 * security hole if you're not on the ball: a malicious server
484 * could send you back _any_ host:port pair, so if you trustingly
485 * connect to the address it gives you then you've just opened the
486 * entire inside of your corporate network just by connecting
487 * through it to a dodgy SSH server. Hence, we must store a list of
488 * host:port pairs we _are_ trying to forward to, and reject a
489 * connection request from the server if it's not in the list.
491 * In SSH 2, each side of the connection minds its own business and
492 * doesn't send unnecessary information to the other. You arrange a
493 * remote forwarding by sending the server just the remote port
494 * number. When a connection comes in, the server tells you which
495 * of its ports was connected to; and _you_ have to remember what
496 * local host:port pair went with that port number.
498 * Hence, in SSH 1 this structure is indexed by destination
499 * host:port pair, whereas in SSH 2 it is indexed by source port.
501 struct ssh_portfwd
; /* forward declaration */
503 struct ssh_rportfwd
{
504 unsigned sport
, dport
;
507 struct ssh_portfwd
*pfrec
;
509 #define free_rportfwd(pf) ( \
510 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
513 * Separately to the rportfwd tree (which is for looking up port
514 * open requests from the server), a tree of _these_ structures is
515 * used to keep track of all the currently open port forwardings,
516 * so that we can reconfigure in mid-session if the user requests
520 enum { DESTROY
, KEEP
, CREATE
} status
;
522 unsigned sport
, dport
;
525 struct ssh_rportfwd
*remote
;
529 #define free_portfwd(pf) ( \
530 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
531 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
536 unsigned long sequence
;
541 long encrypted_len
; /* for SSH2 total-size counting */
544 * State associated with packet logging
548 struct logblank_t
*blanks
;
551 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
552 struct Packet
*pktin
);
553 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
554 struct Packet
*pktin
);
555 static void ssh1_protocol_setup(Ssh ssh
);
556 static void ssh2_protocol_setup(Ssh ssh
);
557 static void ssh_size(void *handle
, int width
, int height
);
558 static void ssh_special(void *handle
, Telnet_Special
);
559 static int ssh2_try_send(struct ssh_channel
*c
);
560 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
561 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
562 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
563 static int ssh_sendbuffer(void *handle
);
564 static void ssh_do_close(Ssh ssh
);
565 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
);
566 static int ssh2_pkt_getbool(struct Packet
*pkt
);
567 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
);
568 static void ssh2_timer(void *ctx
, long now
);
569 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
570 struct Packet
*pktin
);
572 struct rdpkt1_state_tag
{
573 long len
, pad
, biglen
, to_read
;
574 unsigned long realcrc
, gotcrc
;
578 struct Packet
*pktin
;
581 struct rdpkt2_state_tag
{
582 long len
, pad
, payload
, packetlen
, maclen
;
585 unsigned long incoming_sequence
;
586 struct Packet
*pktin
;
589 typedef void (*handler_fn_t
)(Ssh ssh
, struct Packet
*pktin
);
590 typedef void (*chandler_fn_t
)(Ssh ssh
, struct Packet
*pktin
, void *ctx
);
592 struct queued_handler
;
593 struct queued_handler
{
595 chandler_fn_t handler
;
597 struct queued_handler
*next
;
601 const struct plug_function_table
*fn
;
602 /* the above field _must_ be first in the structure */
604 SHA_State exhash
, exhashbase
;
611 unsigned char session_key
[32];
613 int v1_remote_protoflags
;
614 int v1_local_protoflags
;
615 int agentfwd_enabled
;
618 const struct ssh_cipher
*cipher
;
621 const struct ssh2_cipher
*cscipher
, *sccipher
;
622 void *cs_cipher_ctx
, *sc_cipher_ctx
;
623 const struct ssh_mac
*csmac
, *scmac
;
624 void *cs_mac_ctx
, *sc_mac_ctx
;
625 const struct ssh_compress
*cscomp
, *sccomp
;
626 void *cs_comp_ctx
, *sc_comp_ctx
;
627 const struct ssh_kex
*kex
;
628 const struct ssh_signkey
*hostkey
;
629 unsigned char v2_session_id
[20];
635 int echoing
, editing
;
639 int ospeed
, ispeed
; /* temporaries */
640 int term_width
, term_height
;
642 tree234
*channels
; /* indexed by local id */
643 struct ssh_channel
*mainchan
; /* primary session channel */
646 tree234
*rportfwds
, *portfwds
;
650 SSH_STATE_BEFORE_SIZE
,
656 int size_needed
, eof_needed
;
658 struct Packet
**queue
;
659 int queuelen
, queuesize
;
661 unsigned char *deferred_send_data
;
662 int deferred_len
, deferred_size
;
665 * Gross hack: pscp will try to start SFTP but fall back to
666 * scp1 if that fails. This variable is the means by which
667 * scp.c can reach into the SSH code and find out which one it
673 * Used for username and password input.
675 char *userpass_input_buffer
;
676 int userpass_input_buflen
;
677 int userpass_input_bufpos
;
678 int userpass_input_echo
;
685 int v1_throttle_count
;
688 int v1_stdout_throttling
;
689 int v2_outgoing_sequence
;
691 int ssh1_rdpkt_crstate
;
692 int ssh2_rdpkt_crstate
;
693 int do_ssh_init_crstate
;
694 int ssh_gotdata_crstate
;
695 int do_ssh1_login_crstate
;
696 int do_ssh1_connection_crstate
;
697 int do_ssh2_transport_crstate
;
698 int do_ssh2_authconn_crstate
;
700 void *do_ssh_init_state
;
701 void *do_ssh1_login_state
;
702 void *do_ssh2_transport_state
;
703 void *do_ssh2_authconn_state
;
705 struct rdpkt1_state_tag rdpkt1_state
;
706 struct rdpkt2_state_tag rdpkt2_state
;
708 /* ssh1 and ssh2 use this for different things, but both use it */
709 int protocol_initial_phase_done
;
711 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
,
713 struct Packet
*(*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
716 * We maintain a full _copy_ of a Config structure here, not
717 * merely a pointer to it. That way, when we're passed a new
718 * one for reconfiguration, we can check the differences and
719 * potentially reconfigure port forwardings etc in mid-session.
724 * Used to transfer data back from async agent callbacks.
726 void *agent_response
;
727 int agent_response_len
;
730 * Dispatch table for packet types that we may have to deal
733 handler_fn_t packet_dispatch
[256];
736 * Queues of one-off handler functions for success/failure
737 * indications from a request.
739 struct queued_handler
*qhead
, *qtail
;
742 * This module deals with sending keepalives.
747 * Track incoming and outgoing data sizes and time, for
750 unsigned long incoming_data_size
, outgoing_data_size
, deferred_data_size
;
751 unsigned long max_data_size
;
753 long next_rekey
, last_rekey
;
754 char *deferred_rekey_reason
; /* points to STATIC string; don't free */
757 #define logevent(s) logevent(ssh->frontend, s)
759 /* logevent, only printf-formatted. */
760 static void logeventf(Ssh ssh
, const char *fmt
, ...)
766 buf
= dupvprintf(fmt
, ap
);
772 #define bombout(msg) \
774 char *text = dupprintf msg; \
777 connection_fatal(ssh->frontend, "%s", text); \
781 /* Functions to leave bits out of the SSH packet log file. */
783 static void dont_log_password(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
785 if (ssh
->cfg
.logomitpass
)
786 pkt
->logmode
= blanktype
;
789 static void dont_log_data(Ssh ssh
, struct Packet
*pkt
, int blanktype
)
791 if (ssh
->cfg
.logomitdata
)
792 pkt
->logmode
= blanktype
;
795 static void end_log_omission(Ssh ssh
, struct Packet
*pkt
)
797 pkt
->logmode
= PKTLOG_EMIT
;
800 static int ssh_channelcmp(void *av
, void *bv
)
802 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
803 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
804 if (a
->localid
< b
->localid
)
806 if (a
->localid
> b
->localid
)
810 static int ssh_channelfind(void *av
, void *bv
)
812 unsigned *a
= (unsigned *) av
;
813 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
821 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
823 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
824 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
826 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
827 return i
< 0 ?
-1 : +1;
828 if (a
->dport
> b
->dport
)
830 if (a
->dport
< b
->dport
)
835 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
837 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
838 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
840 if (a
->sport
> b
->sport
)
842 if (a
->sport
< b
->sport
)
848 * Special form of strcmp which can cope with NULL inputs. NULL is
849 * defined to sort before even the empty string.
851 static int nullstrcmp(const char *a
, const char *b
)
853 if (a
== NULL
&& b
== NULL
)
862 static int ssh_portcmp(void *av
, void *bv
)
864 struct ssh_portfwd
*a
= (struct ssh_portfwd
*) av
;
865 struct ssh_portfwd
*b
= (struct ssh_portfwd
*) bv
;
867 if (a
->type
> b
->type
)
869 if (a
->type
< b
->type
)
871 if (a
->addressfamily
> b
->addressfamily
)
873 if (a
->addressfamily
< b
->addressfamily
)
875 if ( (i
= nullstrcmp(a
->saddr
, b
->saddr
)) != 0)
876 return i
< 0 ?
-1 : +1;
877 if (a
->sport
> b
->sport
)
879 if (a
->sport
< b
->sport
)
881 if (a
->type
!= 'D') {
882 if ( (i
= nullstrcmp(a
->daddr
, b
->daddr
)) != 0)
883 return i
< 0 ?
-1 : +1;
884 if (a
->dport
> b
->dport
)
886 if (a
->dport
< b
->dport
)
892 static int alloc_channel_id(Ssh ssh
)
894 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
895 unsigned low
, high
, mid
;
897 struct ssh_channel
*c
;
900 * First-fit allocation of channel numbers: always pick the
901 * lowest unused one. To do this, binary-search using the
902 * counted B-tree to find the largest channel ID which is in a
903 * contiguous sequence from the beginning. (Precisely
904 * everything in that sequence must have ID equal to its tree
905 * index plus CHANNEL_NUMBER_OFFSET.)
907 tsize
= count234(ssh
->channels
);
911 while (high
- low
> 1) {
912 mid
= (high
+ low
) / 2;
913 c
= index234(ssh
->channels
, mid
);
914 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
915 low
= mid
; /* this one is fine */
917 high
= mid
; /* this one is past it */
920 * Now low points to either -1, or the tree index of the
921 * largest ID in the initial sequence.
924 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
925 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
927 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
930 static void c_write(Ssh ssh
, const char *buf
, int len
)
932 if ((flags
& FLAG_STDERR
)) {
934 for (i
= 0; i
< len
; i
++)
936 fputc(buf
[i
], stderr
);
939 from_backend(ssh
->frontend
, 1, buf
, len
);
942 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
945 for (i
= 0; i
< len
; i
++) {
947 c_write(ssh
, "\r\n", 2);
948 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
949 c_write(ssh
, buf
+ i
, 1);
953 static void c_write_str(Ssh ssh
, const char *buf
)
955 c_write(ssh
, buf
, strlen(buf
));
958 static void ssh_free_packet(struct Packet
*pkt
)
963 static struct Packet
*ssh_new_packet(void)
965 struct Packet
*pkt
= snew(struct Packet
);
969 pkt
->logmode
= PKTLOG_EMIT
;
977 * Collect incoming data in the incoming packet buffer.
978 * Decipher and verify the packet when it is completely read.
979 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
980 * Update the *data and *datalen variables.
981 * Return a Packet structure when a packet is completed.
983 static struct Packet
*ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
985 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
987 crBegin(ssh
->ssh1_rdpkt_crstate
);
989 st
->pktin
= ssh_new_packet();
992 st
->pktin
->length
= 0;
994 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
995 while ((*datalen
) == 0)
997 st
->len
= (st
->len
<< 8) + **data
;
998 (*data
)++, (*datalen
)--;
1001 st
->pad
= 8 - (st
->len
% 8);
1002 st
->biglen
= st
->len
+ st
->pad
;
1003 st
->pktin
->length
= st
->len
- 5;
1005 if (st
->biglen
< 0) {
1006 bombout(("Extremely large packet length from server suggests"
1007 " data stream corruption"));
1008 ssh_free_packet(st
->pktin
);
1012 st
->pktin
->maxlen
= st
->biglen
;
1013 st
->pktin
->data
= snewn(st
->biglen
+ APIEXTRA
, unsigned char);
1015 st
->to_read
= st
->biglen
;
1016 st
->p
= st
->pktin
->data
;
1017 while (st
->to_read
> 0) {
1018 st
->chunk
= st
->to_read
;
1019 while ((*datalen
) == 0)
1021 if (st
->chunk
> (*datalen
))
1022 st
->chunk
= (*datalen
);
1023 memcpy(st
->p
, *data
, st
->chunk
);
1025 *datalen
-= st
->chunk
;
1027 st
->to_read
-= st
->chunk
;
1030 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, st
->pktin
->data
,
1031 st
->biglen
, NULL
)) {
1032 bombout(("Network attack (CRC compensation) detected!"));
1033 ssh_free_packet(st
->pktin
);
1038 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, st
->pktin
->data
, st
->biglen
);
1040 st
->realcrc
= crc32_compute(st
->pktin
->data
, st
->biglen
- 4);
1041 st
->gotcrc
= GET_32BIT(st
->pktin
->data
+ st
->biglen
- 4);
1042 if (st
->gotcrc
!= st
->realcrc
) {
1043 bombout(("Incorrect CRC received on packet"));
1044 ssh_free_packet(st
->pktin
);
1048 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1049 st
->pktin
->savedpos
= 0;
1051 if (ssh
->v1_compressing
) {
1052 unsigned char *decompblk
;
1054 if (!zlib_decompress_block(ssh
->sc_comp_ctx
,
1055 st
->pktin
->body
- 1, st
->pktin
->length
+ 1,
1056 &decompblk
, &decomplen
)) {
1057 bombout(("Zlib decompression encountered invalid data"));
1058 ssh_free_packet(st
->pktin
);
1062 if (st
->pktin
->maxlen
< st
->pad
+ decomplen
) {
1063 st
->pktin
->maxlen
= st
->pad
+ decomplen
;
1064 st
->pktin
->data
= sresize(st
->pktin
->data
,
1065 st
->pktin
->maxlen
+ APIEXTRA
,
1067 st
->pktin
->body
= st
->pktin
->data
+ st
->pad
+ 1;
1070 memcpy(st
->pktin
->body
- 1, decompblk
, decomplen
);
1072 st
->pktin
->length
= decomplen
- 1;
1075 st
->pktin
->type
= st
->pktin
->body
[-1];
1078 * Log incoming packet, possibly omitting sensitive fields.
1082 struct logblank_t blank
;
1083 if (ssh
->cfg
.logomitdata
) {
1084 int do_blank
= FALSE
, blank_prefix
= 0;
1085 /* "Session data" packets - omit the data field */
1086 if ((st
->pktin
->type
== SSH1_SMSG_STDOUT_DATA
) ||
1087 (st
->pktin
->type
== SSH1_SMSG_STDERR_DATA
)) {
1088 do_blank
= TRUE
; blank_prefix
= 0;
1089 } else if (st
->pktin
->type
== SSH1_MSG_CHANNEL_DATA
) {
1090 do_blank
= TRUE
; blank_prefix
= 4;
1093 blank
.offset
= blank_prefix
;
1094 blank
.len
= st
->pktin
->length
;
1095 blank
.type
= PKTLOG_OMIT
;
1099 log_packet(ssh
->logctx
,
1100 PKT_INCOMING
, st
->pktin
->type
,
1101 ssh1_pkt_type(st
->pktin
->type
),
1102 st
->pktin
->body
, st
->pktin
->length
,
1106 crFinish(st
->pktin
);
1109 static struct Packet
*ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
1111 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
1113 crBegin(ssh
->ssh2_rdpkt_crstate
);
1115 st
->pktin
= ssh_new_packet();
1117 st
->pktin
->type
= 0;
1118 st
->pktin
->length
= 0;
1120 st
->cipherblk
= ssh
->sccipher
->blksize
;
1123 if (st
->cipherblk
< 8)
1126 st
->pktin
->data
= snewn(st
->cipherblk
+ APIEXTRA
, unsigned char);
1129 * Acquire and decrypt the first block of the packet. This will
1130 * contain the length and padding details.
1132 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
1133 while ((*datalen
) == 0)
1135 st
->pktin
->data
[st
->i
] = *(*data
)++;
1140 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1141 st
->pktin
->data
, st
->cipherblk
);
1144 * Now get the length and padding figures.
1146 st
->len
= GET_32BIT(st
->pktin
->data
);
1147 st
->pad
= st
->pktin
->data
[4];
1150 * _Completely_ silly lengths should be stomped on before they
1151 * do us any more damage.
1153 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
1154 bombout(("Incoming packet was garbled on decryption"));
1155 ssh_free_packet(st
->pktin
);
1160 * This enables us to deduce the payload length.
1162 st
->payload
= st
->len
- st
->pad
- 1;
1164 st
->pktin
->length
= st
->payload
+ 5;
1167 * So now we can work out the total packet length.
1169 st
->packetlen
= st
->len
+ 4;
1170 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
1173 * Allocate memory for the rest of the packet.
1175 st
->pktin
->maxlen
= st
->packetlen
+ st
->maclen
;
1176 st
->pktin
->data
= sresize(st
->pktin
->data
,
1177 st
->pktin
->maxlen
+ APIEXTRA
,
1181 * Read and decrypt the remainder of the packet.
1183 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
1185 while ((*datalen
) == 0)
1187 st
->pktin
->data
[st
->i
] = *(*data
)++;
1190 /* Decrypt everything _except_ the MAC. */
1192 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1193 st
->pktin
->data
+ st
->cipherblk
,
1194 st
->packetlen
- st
->cipherblk
);
1196 st
->pktin
->encrypted_len
= st
->packetlen
;
1202 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, st
->pktin
->data
, st
->len
+ 4,
1203 st
->incoming_sequence
)) {
1204 bombout(("Incorrect MAC received on packet"));
1205 ssh_free_packet(st
->pktin
);
1209 st
->pktin
->sequence
= st
->incoming_sequence
++;
1212 * Decompress packet payload.
1215 unsigned char *newpayload
;
1218 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1219 st
->pktin
->data
+ 5, st
->pktin
->length
- 5,
1220 &newpayload
, &newlen
)) {
1221 if (st
->pktin
->maxlen
< newlen
+ 5) {
1222 st
->pktin
->maxlen
= newlen
+ 5;
1223 st
->pktin
->data
= sresize(st
->pktin
->data
,
1224 st
->pktin
->maxlen
+ APIEXTRA
,
1227 st
->pktin
->length
= 5 + newlen
;
1228 memcpy(st
->pktin
->data
+ 5, newpayload
, newlen
);
1233 st
->pktin
->savedpos
= 6;
1234 st
->pktin
->body
= st
->pktin
->data
;
1235 st
->pktin
->type
= st
->pktin
->data
[5];
1238 * Log incoming packet, possibly omitting sensitive fields.
1242 struct logblank_t blank
;
1243 if (ssh
->cfg
.logomitdata
) {
1244 int do_blank
= FALSE
, blank_prefix
= 0;
1245 /* "Session data" packets - omit the data field */
1246 if (st
->pktin
->type
== SSH2_MSG_CHANNEL_DATA
) {
1247 do_blank
= TRUE
; blank_prefix
= 4;
1248 } else if (st
->pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
1249 do_blank
= TRUE
; blank_prefix
= 8;
1252 blank
.offset
= blank_prefix
;
1253 blank
.len
= (st
->pktin
->length
-6) - blank_prefix
;
1254 blank
.type
= PKTLOG_OMIT
;
1258 log_packet(ssh
->logctx
, PKT_INCOMING
, st
->pktin
->type
,
1259 ssh2_pkt_type(ssh
->pkt_ctx
, st
->pktin
->type
),
1260 st
->pktin
->data
+6, st
->pktin
->length
-6,
1264 crFinish(st
->pktin
);
1267 static void ssh1_pktout_size(struct Packet
*pkt
, int len
)
1271 len
+= 5; /* type and CRC */
1272 pad
= 8 - (len
% 8);
1275 pkt
->length
= len
- 5;
1276 if (pkt
->maxlen
< biglen
) {
1277 pkt
->maxlen
= biglen
;
1278 pkt
->data
= sresize(pkt
->data
, biglen
+ 4 + APIEXTRA
, unsigned char);
1280 pkt
->body
= pkt
->data
+ 4 + pad
+ 1;
1283 static struct Packet
*s_wrpkt_start(int type
, int len
)
1285 struct Packet
*pkt
= ssh_new_packet();
1286 ssh1_pktout_size(pkt
, len
);
1288 /* Initialise log omission state */
1294 static int s_wrpkt_prepare(Ssh ssh
, struct Packet
*pkt
)
1300 * XXX various versions of SC (including 8.8.4) screw up the
1301 * register allocation in this function and use the same register
1302 * (D6) for len and as a temporary, with predictable results. The
1303 * following sledgehammer prevents this.
1309 pkt
->body
[-1] = pkt
->type
;
1312 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->type
,
1313 ssh1_pkt_type(pkt
->type
),
1314 pkt
->body
, pkt
->length
,
1315 pkt
->nblanks
, pkt
->blanks
);
1316 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1319 if (ssh
->v1_compressing
) {
1320 unsigned char *compblk
;
1322 zlib_compress_block(ssh
->cs_comp_ctx
,
1323 pkt
->body
- 1, pkt
->length
+ 1,
1324 &compblk
, &complen
);
1325 ssh1_pktout_size(pkt
, complen
- 1);
1326 memcpy(pkt
->body
- 1, compblk
, complen
);
1330 len
= pkt
->length
+ 5; /* type and CRC */
1331 pad
= 8 - (len
% 8);
1334 for (i
= 0; i
< pad
; i
++)
1335 pkt
->data
[i
+ 4] = random_byte();
1336 crc
= crc32_compute(pkt
->data
+ 4, biglen
- 4);
1337 PUT_32BIT(pkt
->data
+ biglen
, crc
);
1338 PUT_32BIT(pkt
->data
, len
);
1341 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, pkt
->data
+ 4, biglen
);
1346 static void s_wrpkt(Ssh ssh
, struct Packet
*pkt
)
1349 len
= s_wrpkt_prepare(ssh
, pkt
);
1350 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1351 if (backlog
> SSH_MAX_BACKLOG
)
1352 ssh_throttle_all(ssh
, 1, backlog
);
1355 static void s_wrpkt_defer(Ssh ssh
, struct Packet
*pkt
)
1358 len
= s_wrpkt_prepare(ssh
, pkt
);
1359 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1360 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1361 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1365 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1366 ssh
->deferred_len
+= len
;
1370 * Construct a packet with the specified contents.
1372 static struct Packet
*construct_packet(Ssh ssh
, int pkttype
,
1373 va_list ap1
, va_list ap2
)
1375 unsigned char *p
, *argp
, argchar
;
1376 unsigned long argint
;
1377 int pktlen
, argtype
, arglen
;
1382 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1385 (void) va_arg(ap1
, int);
1389 (void) va_arg(ap1
, int);
1393 (void) va_arg(ap1
, unsigned char *);
1394 arglen
= va_arg(ap1
, int);
1398 argp
= va_arg(ap1
, unsigned char *);
1399 arglen
= strlen((char *)argp
);
1400 pktlen
+= 4 + arglen
;
1403 bn
= va_arg(ap1
, Bignum
);
1404 pktlen
+= ssh1_bignum_length(bn
);
1409 /* ignore this pass */
1416 pkt
= s_wrpkt_start(pkttype
, pktlen
);
1419 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1420 int offset
= p
- pkt
->body
, len
= 0;
1422 /* Actual fields in the packet */
1424 argint
= va_arg(ap2
, int);
1425 PUT_32BIT(p
, argint
);
1429 argchar
= (unsigned char) va_arg(ap2
, int);
1434 argp
= va_arg(ap2
, unsigned char *);
1435 arglen
= va_arg(ap2
, int);
1436 memcpy(p
, argp
, arglen
);
1440 argp
= va_arg(ap2
, unsigned char *);
1441 arglen
= strlen((char *)argp
);
1442 PUT_32BIT(p
, arglen
);
1443 memcpy(p
+ 4, argp
, arglen
);
1447 bn
= va_arg(ap2
, Bignum
);
1448 len
= ssh1_write_bignum(p
, bn
);
1450 /* Tokens for modifications to packet logging */
1452 dont_log_password(ssh
, pkt
, PKTLOG_BLANK
);
1455 dont_log_data(ssh
, pkt
, PKTLOG_OMIT
);
1458 end_log_omission(ssh
, pkt
);
1462 /* Deal with logfile omission, if required. */
1463 if (len
&& (pkt
->logmode
!= PKTLOG_EMIT
)) {
1465 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
,
1467 pkt
->blanks
[pkt
->nblanks
-1].offset
= offset
;
1468 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1469 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1476 static void send_packet(Ssh ssh
, int pkttype
, ...)
1480 va_start(ap1
, pkttype
);
1481 va_start(ap2
, pkttype
);
1482 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1486 ssh_free_packet(pkt
);
1489 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1493 va_start(ap1
, pkttype
);
1494 va_start(ap2
, pkttype
);
1495 pkt
= construct_packet(ssh
, pkttype
, ap1
, ap2
);
1498 s_wrpkt_defer(ssh
, pkt
);
1499 ssh_free_packet(pkt
);
1502 static int ssh_versioncmp(char *a
, char *b
)
1505 unsigned long av
, bv
;
1507 av
= strtoul(a
, &ae
, 10);
1508 bv
= strtoul(b
, &be
, 10);
1510 return (av
< bv ?
-1 : +1);
1515 av
= strtoul(ae
, &ae
, 10);
1516 bv
= strtoul(be
, &be
, 10);
1518 return (av
< bv ?
-1 : +1);
1523 * Utility routines for putting an SSH-protocol `string' and
1524 * `uint32' into a SHA state.
1527 static void sha_string(SHA_State
* s
, void *str
, int len
)
1529 unsigned char lenblk
[4];
1530 PUT_32BIT(lenblk
, len
);
1531 SHA_Bytes(s
, lenblk
, 4);
1532 SHA_Bytes(s
, str
, len
);
1535 static void sha_uint32(SHA_State
* s
, unsigned i
)
1537 unsigned char intblk
[4];
1538 PUT_32BIT(intblk
, i
);
1539 SHA_Bytes(s
, intblk
, 4);
1543 * SSH2 packet construction functions.
1545 static void ssh2_pkt_ensure(struct Packet
*pkt
, int length
)
1547 if (pkt
->maxlen
< length
) {
1548 pkt
->maxlen
= length
+ 256;
1549 pkt
->data
= sresize(pkt
->data
, pkt
->maxlen
+ APIEXTRA
, unsigned char);
1552 static void ssh2_pkt_adddata(struct Packet
*pkt
, void *data
, int len
)
1554 if (pkt
->logmode
!= PKTLOG_EMIT
) {
1556 pkt
->blanks
= sresize(pkt
->blanks
, pkt
->nblanks
, struct logblank_t
);
1557 pkt
->blanks
[pkt
->nblanks
-1].offset
= pkt
->length
- 6;
1558 pkt
->blanks
[pkt
->nblanks
-1].len
= len
;
1559 pkt
->blanks
[pkt
->nblanks
-1].type
= pkt
->logmode
;
1562 ssh2_pkt_ensure(pkt
, pkt
->length
);
1563 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
1565 static void ssh2_pkt_addbyte(struct Packet
*pkt
, unsigned char byte
)
1567 ssh2_pkt_adddata(pkt
, &byte
, 1);
1569 static struct Packet
*ssh2_pkt_init(int pkt_type
)
1571 struct Packet
*pkt
= ssh_new_packet();
1573 ssh2_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
1576 static void ssh2_pkt_addbool(struct Packet
*pkt
, unsigned char value
)
1578 ssh2_pkt_adddata(pkt
, &value
, 1);
1580 static void ssh2_pkt_adduint32(struct Packet
*pkt
, unsigned long value
)
1583 PUT_32BIT(x
, value
);
1584 ssh2_pkt_adddata(pkt
, x
, 4);
1586 static void ssh2_pkt_addstring_start(struct Packet
*pkt
)
1588 ssh2_pkt_adduint32(pkt
, 0);
1589 pkt
->savedpos
= pkt
->length
;
1591 static void ssh2_pkt_addstring_str(struct Packet
*pkt
, char *data
)
1593 ssh2_pkt_adddata(pkt
, data
, strlen(data
));
1594 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1596 static void ssh2_pkt_addstring_data(struct Packet
*pkt
, char *data
, int len
)
1598 ssh2_pkt_adddata(pkt
, data
, len
);
1599 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
1601 static void ssh2_pkt_addstring(struct Packet
*pkt
, char *data
)
1603 ssh2_pkt_addstring_start(pkt
);
1604 ssh2_pkt_addstring_str(pkt
, data
);
1606 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1609 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1610 p
= snewn(n
+ 1, unsigned char);
1612 fatalbox("out of memory");
1614 for (i
= 1; i
<= n
; i
++)
1615 p
[i
] = bignum_byte(b
, n
- i
);
1617 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1619 memmove(p
, p
+ i
, n
+ 1 - i
);
1623 static void ssh2_pkt_addmp(struct Packet
*pkt
, Bignum b
)
1627 p
= ssh2_mpint_fmt(b
, &len
);
1628 ssh2_pkt_addstring_start(pkt
);
1629 ssh2_pkt_addstring_data(pkt
, (char *)p
, len
);
1634 * Construct an SSH2 final-form packet: compress it, encrypt it,
1635 * put the MAC on it. Final packet, ready to be sent, is stored in
1636 * pkt->data. Total length is returned.
1638 static int ssh2_pkt_construct(Ssh ssh
, struct Packet
*pkt
)
1640 int cipherblk
, maclen
, padding
, i
;
1643 log_packet(ssh
->logctx
, PKT_OUTGOING
, pkt
->data
[5],
1644 ssh2_pkt_type(ssh
->pkt_ctx
, pkt
->data
[5]),
1645 pkt
->data
+ 6, pkt
->length
- 6,
1646 pkt
->nblanks
, pkt
->blanks
);
1647 sfree(pkt
->blanks
); pkt
->blanks
= NULL
;
1651 * Compress packet payload.
1654 unsigned char *newpayload
;
1657 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, pkt
->data
+ 5,
1659 &newpayload
, &newlen
)) {
1661 ssh2_pkt_adddata(pkt
, newpayload
, newlen
);
1667 * Add padding. At least four bytes, and must also bring total
1668 * length (minus MAC) up to a multiple of the block size.
1670 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1671 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1674 (cipherblk
- (pkt
->length
+ padding
) % cipherblk
) % cipherblk
;
1675 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1676 ssh2_pkt_ensure(pkt
, pkt
->length
+ padding
+ maclen
);
1677 pkt
->data
[4] = padding
;
1678 for (i
= 0; i
< padding
; i
++)
1679 pkt
->data
[pkt
->length
+ i
] = random_byte();
1680 PUT_32BIT(pkt
->data
, pkt
->length
+ padding
- 4);
1682 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, pkt
->data
,
1683 pkt
->length
+ padding
,
1684 ssh
->v2_outgoing_sequence
);
1685 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1688 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1689 pkt
->data
, pkt
->length
+ padding
);
1691 pkt
->encrypted_len
= pkt
->length
+ padding
;
1693 /* Ready-to-send packet starts at pkt->data. We return length. */
1694 return pkt
->length
+ padding
+ maclen
;
1698 * Routines called from the main SSH code to send packets. There
1699 * are quite a few of these, because we have two separate
1700 * mechanisms for delaying the sending of packets:
1702 * - In order to send an IGNORE message and a password message in
1703 * a single fixed-length blob, we require the ability to
1704 * concatenate the encrypted forms of those two packets _into_ a
1705 * single blob and then pass it to our <network.h> transport
1706 * layer in one go. Hence, there's a deferment mechanism which
1707 * works after packet encryption.
1709 * - In order to avoid sending any connection-layer messages
1710 * during repeat key exchange, we have to queue up any such
1711 * outgoing messages _before_ they are encrypted (and in
1712 * particular before they're allocated sequence numbers), and
1713 * then send them once we've finished.
1715 * I call these mechanisms `defer' and `queue' respectively, so as
1716 * to distinguish them reasonably easily.
1718 * The functions send_noqueue() and defer_noqueue() free the packet
1719 * structure they are passed. Every outgoing packet goes through
1720 * precisely one of these functions in its life; packets passed to
1721 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1722 * these or get queued, and then when the queue is later emptied
1723 * the packets are all passed to defer_noqueue().
1727 * Send an SSH2 packet immediately, without queuing or deferring.
1729 static void ssh2_pkt_send_noqueue(Ssh ssh
, struct Packet
*pkt
)
1733 len
= ssh2_pkt_construct(ssh
, pkt
);
1734 backlog
= sk_write(ssh
->s
, (char *)pkt
->data
, len
);
1735 if (backlog
> SSH_MAX_BACKLOG
)
1736 ssh_throttle_all(ssh
, 1, backlog
);
1738 ssh
->outgoing_data_size
+= pkt
->encrypted_len
;
1739 if (!ssh
->kex_in_progress
&&
1740 ssh
->max_data_size
!= 0 &&
1741 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1742 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1744 ssh_free_packet(pkt
);
1748 * Defer an SSH2 packet.
1750 static void ssh2_pkt_defer_noqueue(Ssh ssh
, struct Packet
*pkt
)
1752 int len
= ssh2_pkt_construct(ssh
, pkt
);
1753 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1754 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1755 ssh
->deferred_send_data
= sresize(ssh
->deferred_send_data
,
1759 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, pkt
->data
, len
);
1760 ssh
->deferred_len
+= len
;
1761 ssh
->deferred_data_size
+= pkt
->encrypted_len
;
1762 ssh_free_packet(pkt
);
1766 * Queue an SSH2 packet.
1768 static void ssh2_pkt_queue(Ssh ssh
, struct Packet
*pkt
)
1770 assert(ssh
->queueing
);
1772 if (ssh
->queuelen
>= ssh
->queuesize
) {
1773 ssh
->queuesize
= ssh
->queuelen
+ 32;
1774 ssh
->queue
= sresize(ssh
->queue
, ssh
->queuesize
, struct Packet
*);
1777 ssh
->queue
[ssh
->queuelen
++] = pkt
;
1781 * Either queue or send a packet, depending on whether queueing is
1784 static void ssh2_pkt_send(Ssh ssh
, struct Packet
*pkt
)
1787 ssh2_pkt_queue(ssh
, pkt
);
1789 ssh2_pkt_send_noqueue(ssh
, pkt
);
1793 * Either queue or defer a packet, depending on whether queueing is
1796 static void ssh2_pkt_defer(Ssh ssh
, struct Packet
*pkt
)
1799 ssh2_pkt_queue(ssh
, pkt
);
1801 ssh2_pkt_defer_noqueue(ssh
, pkt
);
1805 * Send the whole deferred data block constructed by
1806 * ssh2_pkt_defer() or SSH1's defer_packet().
1808 * The expected use of the defer mechanism is that you call
1809 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1810 * not currently queueing, this simply sets up deferred_send_data
1811 * and then sends it. If we _are_ currently queueing, the calls to
1812 * ssh2_pkt_defer() put the deferred packets on to the queue
1813 * instead, and therefore ssh_pkt_defersend() has no deferred data
1814 * to send. Hence, there's no need to make it conditional on
1817 static void ssh_pkt_defersend(Ssh ssh
)
1820 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1822 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1823 sfree(ssh
->deferred_send_data
);
1824 ssh
->deferred_send_data
= NULL
;
1825 if (backlog
> SSH_MAX_BACKLOG
)
1826 ssh_throttle_all(ssh
, 1, backlog
);
1828 ssh
->outgoing_data_size
+= ssh
->deferred_data_size
;
1829 if (!ssh
->kex_in_progress
&&
1830 ssh
->max_data_size
!= 0 &&
1831 ssh
->outgoing_data_size
> ssh
->max_data_size
)
1832 do_ssh2_transport(ssh
, "too much data sent", -1, NULL
);
1833 ssh
->deferred_data_size
= 0;
1837 * Send all queued SSH2 packets. We send them by means of
1838 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1839 * packets that needed to be lumped together.
1841 static void ssh2_pkt_queuesend(Ssh ssh
)
1845 assert(!ssh
->queueing
);
1847 for (i
= 0; i
< ssh
->queuelen
; i
++)
1848 ssh2_pkt_defer_noqueue(ssh
, ssh
->queue
[i
]);
1851 ssh_pkt_defersend(ssh
);
1855 void bndebug(char *string
, Bignum b
)
1859 p
= ssh2_mpint_fmt(b
, &len
);
1860 debug(("%s", string
));
1861 for (i
= 0; i
< len
; i
++)
1862 debug((" %02x", p
[i
]));
1868 static void sha_mpint(SHA_State
* s
, Bignum b
)
1872 p
= ssh2_mpint_fmt(b
, &len
);
1873 sha_string(s
, p
, len
);
1878 * Packet decode functions for both SSH1 and SSH2.
1880 static unsigned long ssh_pkt_getuint32(struct Packet
*pkt
)
1882 unsigned long value
;
1883 if (pkt
->length
- pkt
->savedpos
< 4)
1884 return 0; /* arrgh, no way to decline (FIXME?) */
1885 value
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1889 static int ssh2_pkt_getbool(struct Packet
*pkt
)
1891 unsigned long value
;
1892 if (pkt
->length
- pkt
->savedpos
< 1)
1893 return 0; /* arrgh, no way to decline (FIXME?) */
1894 value
= pkt
->body
[pkt
->savedpos
] != 0;
1898 static void ssh_pkt_getstring(struct Packet
*pkt
, char **p
, int *length
)
1903 if (pkt
->length
- pkt
->savedpos
< 4)
1905 len
= GET_32BIT(pkt
->body
+ pkt
->savedpos
);
1910 if (pkt
->length
- pkt
->savedpos
< *length
)
1912 *p
= (char *)(pkt
->body
+ pkt
->savedpos
);
1913 pkt
->savedpos
+= *length
;
1915 static void *ssh_pkt_getdata(struct Packet
*pkt
, int length
)
1917 if (pkt
->length
- pkt
->savedpos
< length
)
1919 pkt
->savedpos
+= length
;
1920 return pkt
->body
+ (pkt
->savedpos
- length
);
1922 static int ssh1_pkt_getrsakey(struct Packet
*pkt
, struct RSAKey
*key
,
1923 unsigned char **keystr
)
1927 j
= makekey(pkt
->body
+ pkt
->savedpos
,
1928 pkt
->length
- pkt
->savedpos
,
1935 assert(pkt
->savedpos
< pkt
->length
);
1939 static Bignum
ssh1_pkt_getmp(struct Packet
*pkt
)
1944 j
= ssh1_read_bignum(pkt
->body
+ pkt
->savedpos
,
1945 pkt
->length
- pkt
->savedpos
, &b
);
1953 static Bignum
ssh2_pkt_getmp(struct Packet
*pkt
)
1959 ssh_pkt_getstring(pkt
, &p
, &length
);
1964 b
= bignum_from_bytes((unsigned char *)p
, length
);
1969 * Helper function to add an SSH2 signature blob to a packet.
1970 * Expects to be shown the public key blob as well as the signature
1971 * blob. Normally works just like ssh2_pkt_addstring, but will
1972 * fiddle with the signature packet if necessary for
1973 * BUG_SSH2_RSA_PADDING.
1975 static void ssh2_add_sigblob(Ssh ssh
, struct Packet
*pkt
,
1976 void *pkblob_v
, int pkblob_len
,
1977 void *sigblob_v
, int sigblob_len
)
1979 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1980 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1982 /* dmemdump(pkblob, pkblob_len); */
1983 /* dmemdump(sigblob, sigblob_len); */
1986 * See if this is in fact an ssh-rsa signature and a buggy
1987 * server; otherwise we can just do this the easy way.
1989 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1990 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1991 int pos
, len
, siglen
;
1994 * Find the byte length of the modulus.
1997 pos
= 4+7; /* skip over "ssh-rsa" */
1998 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1999 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
2000 pos
+= 4; /* find modulus itself */
2001 while (len
> 0 && pkblob
[pos
] == 0)
2003 /* debug(("modulus length is %d\n", len)); */
2006 * Now find the signature integer.
2008 pos
= 4+7; /* skip over "ssh-rsa" */
2009 siglen
= GET_32BIT(sigblob
+pos
);
2010 /* debug(("signature length is %d\n", siglen)); */
2012 if (len
!= siglen
) {
2013 unsigned char newlen
[4];
2014 ssh2_pkt_addstring_start(pkt
);
2015 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, pos
);
2016 /* dmemdump(sigblob, pos); */
2017 pos
+= 4; /* point to start of actual sig */
2018 PUT_32BIT(newlen
, len
);
2019 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 4);
2020 /* dmemdump(newlen, 4); */
2022 while (len
-- > siglen
) {
2023 ssh2_pkt_addstring_data(pkt
, (char *)newlen
, 1);
2024 /* dmemdump(newlen, 1); */
2026 ssh2_pkt_addstring_data(pkt
, (char *)(sigblob
+pos
), siglen
);
2027 /* dmemdump(sigblob+pos, siglen); */
2031 /* Otherwise fall through and do it the easy way. */
2034 ssh2_pkt_addstring_start(pkt
);
2035 ssh2_pkt_addstring_data(pkt
, (char *)sigblob
, sigblob_len
);
2039 * Examine the remote side's version string and compare it against
2040 * a list of known buggy implementations.
2042 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
2044 char *imp
; /* pointer to implementation part */
2046 imp
+= strcspn(imp
, "-");
2048 imp
+= strcspn(imp
, "-");
2051 ssh
->remote_bugs
= 0;
2053 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
2054 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
2055 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
2056 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
2057 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25") ||
2058 !strcmp(imp
, "OSU_1.4alpha3") || !strcmp(imp
, "OSU_1.5alpha4")))) {
2060 * These versions don't support SSH1_MSG_IGNORE, so we have
2061 * to use a different defence against password length
2064 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
2065 logevent("We believe remote version has SSH1 ignore bug");
2068 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
2069 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
2070 (!strcmp(imp
, "Cisco-1.25") || !strcmp(imp
, "OSU_1.4alpha3")))) {
2072 * These versions need a plain password sent; they can't
2073 * handle having a null and a random length of data after
2076 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
2077 logevent("We believe remote version needs a plain SSH1 password");
2080 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
2081 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
2082 (!strcmp(imp
, "Cisco-1.25")))) {
2084 * These versions apparently have no clue whatever about
2085 * RSA authentication and will panic and die if they see
2086 * an AUTH_RSA message.
2088 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
2089 logevent("We believe remote version can't handle RSA authentication");
2092 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
2093 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
2094 !wc_match("* VShell", imp
) &&
2095 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
2096 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
2097 wc_match("2.1 *", imp
)))) {
2099 * These versions have the HMAC bug.
2101 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
2102 logevent("We believe remote version has SSH2 HMAC bug");
2105 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
2106 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
2107 !wc_match("* VShell", imp
) &&
2108 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
2110 * These versions have the key-derivation bug (failing to
2111 * include the literal shared secret in the hashes that
2112 * generate the keys).
2114 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
2115 logevent("We believe remote version has SSH2 key-derivation bug");
2118 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
2119 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
2120 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
2121 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
2123 * These versions have the SSH2 RSA padding bug.
2125 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
2126 logevent("We believe remote version has SSH2 RSA padding bug");
2129 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
2130 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
2131 wc_match("OpenSSH_2.[0-2]*", imp
))) {
2133 * These versions have the SSH2 session-ID bug in
2134 * public-key authentication.
2136 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
2137 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2140 if (ssh
->cfg
.sshbug_rekey2
== FORCE_ON
||
2141 (ssh
->cfg
.sshbug_rekey2
== AUTO
&&
2142 (wc_match("Sun_SSH_1.0", imp
) ||
2143 wc_match("Sun_SSH_1.0.1", imp
)))) {
2145 * These versions have the SSH2 ignore-rekey bug.
2147 ssh
->remote_bugs
|= BUG_SSH2_REKEY
;
2148 logevent("We believe remote version has SSH2 ignore-rekey bug");
2153 * The `software version' part of an SSH version string is required
2154 * to contain no spaces or minus signs.
2156 static void ssh_fix_verstring(char *str
)
2158 /* Eat "SSH-<protoversion>-". */
2159 assert(*str
== 'S'); str
++;
2160 assert(*str
== 'S'); str
++;
2161 assert(*str
== 'H'); str
++;
2162 assert(*str
== '-'); str
++;
2163 while (*str
&& *str
!= '-') str
++;
2164 assert(*str
== '-'); str
++;
2166 /* Convert minus signs and spaces in the remaining string into
2169 if (*str
== '-' || *str
== ' ')
2175 static int do_ssh_init(Ssh ssh
, unsigned char c
)
2177 struct do_ssh_init_state
{
2185 crState(do_ssh_init_state
);
2187 crBegin(ssh
->do_ssh_init_crstate
);
2189 /* Search for the string "SSH-" in the input. */
2192 static const int transS
[] = { 1, 2, 2, 1 };
2193 static const int transH
[] = { 0, 0, 3, 0 };
2194 static const int transminus
[] = { 0, 0, 0, -1 };
2196 s
->i
= transS
[s
->i
];
2198 s
->i
= transH
[s
->i
];
2200 s
->i
= transminus
[s
->i
];
2205 crReturn(1); /* get another character */
2209 s
->vstring
= snewn(s
->vstrsize
, char);
2210 strcpy(s
->vstring
, "SSH-");
2214 crReturn(1); /* get another char */
2215 if (s
->vslen
>= s
->vstrsize
- 1) {
2217 s
->vstring
= sresize(s
->vstring
, s
->vstrsize
, char);
2219 s
->vstring
[s
->vslen
++] = c
;
2222 s
->version
[s
->i
] = '\0';
2224 } else if (s
->i
< sizeof(s
->version
) - 1)
2225 s
->version
[s
->i
++] = c
;
2226 } else if (c
== '\012')
2230 ssh
->agentfwd_enabled
= FALSE
;
2231 ssh
->rdpkt2_state
.incoming_sequence
= 0;
2233 s
->vstring
[s
->vslen
] = 0;
2234 s
->vstring
[strcspn(s
->vstring
, "\015\012")] = '\0';/* remove EOL chars */
2237 vlog
= snewn(20 + s
->vslen
, char);
2238 sprintf(vlog
, "Server version: %s", s
->vstring
);
2242 ssh_detect_bugs(ssh
, s
->vstring
);
2245 * Decide which SSH protocol version to support.
2248 /* Anything strictly below "2.0" means protocol 1 is supported. */
2249 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
2250 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
2251 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
2253 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
2254 bombout(("SSH protocol version 1 required by user but not provided by server"));
2257 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
2258 bombout(("SSH protocol version 2 required by user but not provided by server"));
2265 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
2267 * Construct a v2 version string.
2269 verstring
= dupprintf("SSH-2.0-%s\015\012", sshver
);
2273 * Construct a v1 version string.
2275 verstring
= dupprintf("SSH-%s-%s\012",
2276 (ssh_versioncmp(s
->version
, "1.5") <= 0 ?
2277 s
->version
: "1.5"),
2282 ssh_fix_verstring(verstring
);
2284 if (ssh
->version
== 2) {
2286 * Hash our version string and their version string.
2288 SHA_Init(&ssh
->exhashbase
);
2289 sha_string(&ssh
->exhashbase
, verstring
,
2290 strcspn(verstring
, "\015\012"));
2291 sha_string(&ssh
->exhashbase
, s
->vstring
,
2292 strcspn(s
->vstring
, "\015\012"));
2295 * Initialise SSHv2 protocol.
2297 ssh
->protocol
= ssh2_protocol
;
2298 ssh2_protocol_setup(ssh
);
2299 ssh
->s_rdpkt
= ssh2_rdpkt
;
2302 * Initialise SSHv1 protocol.
2304 ssh
->protocol
= ssh1_protocol
;
2305 ssh1_protocol_setup(ssh
);
2306 ssh
->s_rdpkt
= ssh1_rdpkt
;
2308 logeventf(ssh
, "We claim version: %.*s",
2309 strcspn(verstring
, "\015\012"), verstring
);
2310 sk_write(ssh
->s
, verstring
, strlen(verstring
));
2314 logeventf(ssh
, "Using SSH protocol version %d", ssh
->version
);
2316 update_specials_menu(ssh
->frontend
);
2317 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
2318 ssh
->pinger
= pinger_new(&ssh
->cfg
, &ssh_backend
, ssh
);
2325 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
2327 crBegin(ssh
->ssh_gotdata_crstate
);
2330 * To begin with, feed the characters one by one to the
2331 * protocol initialisation / selection function do_ssh_init().
2332 * When that returns 0, we're done with the initial greeting
2333 * exchange and can move on to packet discipline.
2336 int ret
; /* need not be kept across crReturn */
2338 crReturnV
; /* more data please */
2339 ret
= do_ssh_init(ssh
, *data
);
2347 * We emerge from that loop when the initial negotiation is
2348 * over and we have selected an s_rdpkt function. Now pass
2349 * everything to s_rdpkt, and then pass the resulting packets
2350 * to the proper protocol handler.
2355 while (datalen
> 0) {
2356 struct Packet
*pktin
= ssh
->s_rdpkt(ssh
, &data
, &datalen
);
2358 ssh
->protocol(ssh
, NULL
, 0, pktin
);
2359 ssh_free_packet(pktin
);
2361 if (ssh
->state
== SSH_STATE_CLOSED
)
2369 static void ssh_do_close(Ssh ssh
)
2372 struct ssh_channel
*c
;
2374 ssh
->state
= SSH_STATE_CLOSED
;
2378 notify_remote_exit(ssh
->frontend
);
2381 * Now we must shut down any port and X forwardings going
2382 * through this connection.
2384 if (ssh
->channels
) {
2385 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2388 x11_close(c
->u
.x11
.s
);
2391 pfd_close(c
->u
.pfd
.s
);
2394 del234(ssh
->channels
, c
);
2395 if (ssh
->version
== 2)
2396 bufchain_clear(&c
->v
.v2
.outbuffer
);
2402 static int ssh_closing(Plug plug
, const char *error_msg
, int error_code
,
2405 Ssh ssh
= (Ssh
) plug
;
2408 /* A socket error has occurred. */
2409 logevent(error_msg
);
2410 connection_fatal(ssh
->frontend
, "%s", error_msg
);
2412 /* Otherwise, the remote side closed the connection normally. */
2417 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2419 Ssh ssh
= (Ssh
) plug
;
2420 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2421 if (ssh
->state
== SSH_STATE_CLOSED
) {
2428 static void ssh_sent(Plug plug
, int bufsize
)
2430 Ssh ssh
= (Ssh
) plug
;
2432 * If the send backlog on the SSH socket itself clears, we
2433 * should unthrottle the whole world if it was throttled.
2435 if (bufsize
< SSH_MAX_BACKLOG
)
2436 ssh_throttle_all(ssh
, 0, bufsize
);
2440 * Connect to specified host and port.
2441 * Returns an error message, or NULL on success.
2442 * Also places the canonical host name into `realhost'. It must be
2443 * freed by the caller.
2445 static const char *connect_to_host(Ssh ssh
, char *host
, int port
,
2446 char **realhost
, int nodelay
, int keepalive
)
2448 static const struct plug_function_table fn_table
= {
2458 ssh
->savedhost
= snewn(1 + strlen(host
), char);
2459 if (!ssh
->savedhost
)
2460 fatalbox("Out of memory");
2461 strcpy(ssh
->savedhost
, host
);
2464 port
= 22; /* default ssh port */
2465 ssh
->savedport
= port
;
2470 logeventf(ssh
, "Looking up host \"%s\"%s", host
,
2471 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV4 ?
" (IPv4)" :
2472 (ssh
->cfg
.addressfamily
== ADDRTYPE_IPV6 ?
" (IPv6)" : "")));
2473 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
,
2474 ssh
->cfg
.addressfamily
);
2475 if ((err
= sk_addr_error(addr
)) != NULL
) {
2485 sk_getaddr(addr
, addrbuf
, 100);
2486 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2488 ssh
->fn
= &fn_table
;
2489 ssh
->s
= new_connection(addr
, *realhost
, port
,
2490 0, 1, nodelay
, keepalive
, (Plug
) ssh
, &ssh
->cfg
);
2491 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2493 notify_remote_exit(ssh
->frontend
);
2501 * Throttle or unthrottle the SSH connection.
2503 static void ssh1_throttle(Ssh ssh
, int adjust
)
2505 int old_count
= ssh
->v1_throttle_count
;
2506 ssh
->v1_throttle_count
+= adjust
;
2507 assert(ssh
->v1_throttle_count
>= 0);
2508 if (ssh
->v1_throttle_count
&& !old_count
) {
2509 sk_set_frozen(ssh
->s
, 1);
2510 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2511 sk_set_frozen(ssh
->s
, 0);
2516 * Throttle or unthrottle _all_ local data streams (for when sends
2517 * on the SSH connection itself back up).
2519 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2522 struct ssh_channel
*c
;
2524 if (enable
== ssh
->throttled_all
)
2526 ssh
->throttled_all
= enable
;
2527 ssh
->overall_bufsize
= bufsize
;
2530 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2532 case CHAN_MAINSESSION
:
2534 * This is treated separately, outside the switch.
2538 x11_override_throttle(c
->u
.x11
.s
, enable
);
2541 /* Agent channels require no buffer management. */
2544 pfd_override_throttle(c
->u
.pfd
.s
, enable
);
2551 * Username and password input, abstracted off into routines
2552 * reusable in several places - even between SSH1 and SSH2.
2555 /* Set up a username or password input loop on a given buffer. */
2556 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2558 ssh
->userpass_input_buffer
= buffer
;
2559 ssh
->userpass_input_buflen
= buflen
;
2560 ssh
->userpass_input_bufpos
= 0;
2561 ssh
->userpass_input_echo
= echo
;
2565 * Process some terminal data in the course of username/password
2566 * input. Returns >0 for success (line of input returned in
2567 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2568 * for inconclusive (keep waiting for more input please).
2570 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2575 switch (c
= *in
++) {
2578 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2579 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2584 if (ssh
->userpass_input_bufpos
> 0) {
2585 if (ssh
->userpass_input_echo
)
2586 c_write_str(ssh
, "\b \b");
2587 ssh
->userpass_input_bufpos
--;
2592 while (ssh
->userpass_input_bufpos
> 0) {
2593 if (ssh
->userpass_input_echo
)
2594 c_write_str(ssh
, "\b \b");
2595 ssh
->userpass_input_bufpos
--;
2604 * This simplistic check for printability is disabled
2605 * when we're doing password input, because some people
2606 * have control characters in their passwords.o
2608 if ((!ssh
->userpass_input_echo
||
2609 (c
>= ' ' && c
<= '~') ||
2610 ((unsigned char) c
>= 160))
2611 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2612 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2613 if (ssh
->userpass_input_echo
)
2614 c_write(ssh
, &c
, 1);
2622 static void ssh_agent_callback(void *sshv
, void *reply
, int replylen
)
2624 Ssh ssh
= (Ssh
) sshv
;
2626 ssh
->agent_response
= reply
;
2627 ssh
->agent_response_len
= replylen
;
2629 if (ssh
->version
== 1)
2630 do_ssh1_login(ssh
, NULL
, -1, NULL
);
2632 do_ssh2_authconn(ssh
, NULL
, -1, NULL
);
2635 static void ssh_agentf_callback(void *cv
, void *reply
, int replylen
)
2637 struct ssh_channel
*c
= (struct ssh_channel
*)cv
;
2639 void *sentreply
= reply
;
2642 /* Fake SSH_AGENT_FAILURE. */
2643 sentreply
= "\0\0\0\1\5";
2646 if (ssh
->version
== 2) {
2647 ssh2_add_channel_data(c
, sentreply
, replylen
);
2650 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
2651 PKT_INT
, c
->remoteid
,
2654 PKT_DATA
, sentreply
, replylen
,
2663 * Handle the key exchange and user authentication phases.
2665 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
,
2666 struct Packet
*pktin
)
2669 unsigned char cookie
[8], *ptr
;
2670 struct RSAKey servkey
, hostkey
;
2671 struct MD5Context md5c
;
2672 struct do_ssh1_login_state
{
2674 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2675 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2676 int tried_publickey
, tried_agent
;
2677 int tis_auth_refused
, ccard_auth_refused
;
2678 unsigned char session_id
[16];
2681 void *publickey_blob
;
2682 int publickey_bloblen
;
2688 unsigned char request
[5], *response
, *p
;
2697 crState(do_ssh1_login_state
);
2699 crBegin(ssh
->do_ssh1_login_crstate
);
2704 if (pktin
->type
!= SSH1_SMSG_PUBLIC_KEY
) {
2705 bombout(("Public key packet not received"));
2709 logevent("Received public keys");
2711 ptr
= ssh_pkt_getdata(pktin
, 8);
2713 bombout(("SSH1 public key packet stopped before random cookie"));
2716 memcpy(cookie
, ptr
, 8);
2718 if (!ssh1_pkt_getrsakey(pktin
, &servkey
, &s
->keystr1
) ||
2719 !ssh1_pkt_getrsakey(pktin
, &hostkey
, &s
->keystr2
)) {
2720 bombout(("Failed to read SSH1 public keys from public key packet"));
2725 * Log the host key fingerprint.
2729 logevent("Host key fingerprint is:");
2730 strcpy(logmsg
, " ");
2731 hostkey
.comment
= NULL
;
2732 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2733 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2737 ssh
->v1_remote_protoflags
= ssh_pkt_getuint32(pktin
);
2738 s
->supported_ciphers_mask
= ssh_pkt_getuint32(pktin
);
2739 s
->supported_auths_mask
= ssh_pkt_getuint32(pktin
);
2741 ssh
->v1_local_protoflags
=
2742 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2743 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2746 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2747 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2748 MD5Update(&md5c
, cookie
, 8);
2749 MD5Final(s
->session_id
, &md5c
);
2751 for (i
= 0; i
< 32; i
++)
2752 ssh
->session_key
[i
] = random_byte();
2755 * Verify that the `bits' and `bytes' parameters match.
2757 if (hostkey
.bits
> hostkey
.bytes
* 8 ||
2758 servkey
.bits
> servkey
.bytes
* 8) {
2759 bombout(("SSH1 public keys were badly formatted"));
2763 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2765 s
->rsabuf
= snewn(s
->len
, unsigned char);
2767 fatalbox("Out of memory");
2770 * Verify the host key.
2774 * First format the key into a string.
2776 int len
= rsastr_len(&hostkey
);
2777 char fingerprint
[100];
2778 char *keystr
= snewn(len
, char);
2780 fatalbox("Out of memory");
2781 rsastr_fmt(keystr
, &hostkey
);
2782 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2783 verify_ssh_host_key(ssh
->frontend
,
2784 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2789 for (i
= 0; i
< 32; i
++) {
2790 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2792 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2795 if (hostkey
.bytes
> servkey
.bytes
) {
2796 ret
= rsaencrypt(s
->rsabuf
, 32, &servkey
);
2798 ret
= rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2800 ret
= rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2802 ret
= rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2805 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2809 logevent("Encrypted session key");
2812 int cipher_chosen
= 0, warn
= 0;
2813 char *cipher_string
= NULL
;
2815 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2816 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2817 if (next_cipher
== CIPHER_WARN
) {
2818 /* If/when we choose a cipher, warn about it */
2820 } else if (next_cipher
== CIPHER_AES
) {
2821 /* XXX Probably don't need to mention this. */
2822 logevent("AES not supported in SSH1, skipping");
2824 switch (next_cipher
) {
2825 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2826 cipher_string
= "3DES"; break;
2827 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2828 cipher_string
= "Blowfish"; break;
2829 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2830 cipher_string
= "single-DES"; break;
2832 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2836 if (!cipher_chosen
) {
2837 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2838 bombout(("Server violates SSH 1 protocol by not "
2839 "supporting 3DES encryption"));
2841 /* shouldn't happen */
2842 bombout(("No supported ciphers found"));
2846 /* Warn about chosen cipher if necessary. */
2848 sk_set_frozen(ssh
->s
, 1);
2849 askalg(ssh
->frontend
, "cipher", cipher_string
);
2850 sk_set_frozen(ssh
->s
, 0);
2854 switch (s
->cipher_type
) {
2855 case SSH_CIPHER_3DES
:
2856 logevent("Using 3DES encryption");
2858 case SSH_CIPHER_DES
:
2859 logevent("Using single-DES encryption");
2861 case SSH_CIPHER_BLOWFISH
:
2862 logevent("Using Blowfish encryption");
2866 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2867 PKT_CHAR
, s
->cipher_type
,
2868 PKT_DATA
, cookie
, 8,
2869 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2870 PKT_DATA
, s
->rsabuf
, s
->len
,
2871 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2873 logevent("Trying to enable encryption...");
2877 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2878 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2880 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2881 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2882 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2884 ssh
->crcda_ctx
= crcda_make_context();
2885 logevent("Installing CRC compensation attack detector");
2887 if (servkey
.modulus
) {
2888 sfree(servkey
.modulus
);
2889 servkey
.modulus
= NULL
;
2891 if (servkey
.exponent
) {
2892 sfree(servkey
.exponent
);
2893 servkey
.exponent
= NULL
;
2895 if (hostkey
.modulus
) {
2896 sfree(hostkey
.modulus
);
2897 hostkey
.modulus
= NULL
;
2899 if (hostkey
.exponent
) {
2900 sfree(hostkey
.exponent
);
2901 hostkey
.exponent
= NULL
;
2905 if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
2906 bombout(("Encryption not successfully enabled"));
2910 logevent("Successfully started encryption");
2914 if (!*ssh
->cfg
.username
) {
2915 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2916 if (!ssh_get_line("login as: ",
2917 s
->username
, sizeof(s
->username
), FALSE
)) {
2919 * get_line failed to get a username.
2922 logevent("No username provided. Abandoning session.");
2923 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
2927 int ret
; /* need not be kept over crReturn */
2928 c_write_str(ssh
, "login as: ");
2931 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2933 crWaitUntil(!pktin
);
2934 ret
= process_userpass_input(ssh
, in
, inlen
);
2938 c_write_str(ssh
, "\r\n");
2941 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2942 s
->username
[sizeof(s
->username
)-1] = '\0';
2945 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2947 char userlog
[22 + sizeof(s
->username
)];
2948 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2950 if (flags
& FLAG_INTERACTIVE
&&
2951 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2952 strcat(userlog
, "\r\n");
2953 c_write_str(ssh
, userlog
);
2960 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2961 /* We must not attempt PK auth. Pretend we've already tried it. */
2962 s
->tried_publickey
= s
->tried_agent
= 1;
2964 s
->tried_publickey
= s
->tried_agent
= 0;
2966 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2967 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2968 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2969 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2970 &s
->publickey_blob
, &s
->publickey_bloblen
, NULL
))
2971 s
->publickey_blob
= NULL
;
2973 s
->publickey_blob
= NULL
;
2975 while (pktin
->type
== SSH1_SMSG_FAILURE
) {
2976 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2978 if (agent_exists() && !s
->tried_agent
) {
2980 * Attempt RSA authentication using Pageant.
2986 logevent("Pageant is running. Requesting keys.");
2988 /* Request the keys held by the agent. */
2989 PUT_32BIT(s
->request
, 1);
2990 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2991 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
2992 ssh_agent_callback
, ssh
)) {
2996 bombout(("Unexpected data from server while waiting"
2997 " for agent response"));
3000 } while (pktin
|| inlen
> 0);
3001 r
= ssh
->agent_response
;
3002 s
->responselen
= ssh
->agent_response_len
;
3004 s
->response
= (unsigned char *) r
;
3005 if (s
->response
&& s
->responselen
>= 5 &&
3006 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
3007 s
->p
= s
->response
+ 5;
3008 s
->nkeys
= GET_32BIT(s
->p
);
3012 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
3015 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
3018 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
3021 if (s
->publickey_blob
&&
3022 !memcmp(s
->p
, s
->publickey_blob
,
3023 s
->publickey_bloblen
)) {
3024 logevent("This key matches configured key file");
3025 s
->tried_publickey
= 1;
3030 do { /* do while (0) to make breaking easy */
3031 n
= ssh1_read_bignum
3032 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3037 n
= ssh1_read_bignum
3038 (s
->p
, s
->responselen
-(s
->p
-s
->response
),
3043 if (s
->responselen
- (s
->p
-s
->response
) < 4)
3045 s
->commentlen
= GET_32BIT(s
->p
);
3047 if (s
->responselen
- (s
->p
-s
->response
) <
3050 s
->commentp
= (char *)s
->p
;
3051 s
->p
+= s
->commentlen
;
3055 logevent("Pageant key list packet was truncated");
3059 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3060 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3062 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3063 logevent("Key refused");
3066 logevent("Received RSA challenge");
3067 if ((s
->challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3068 bombout(("Server's RSA challenge was badly formatted"));
3073 char *agentreq
, *q
, *ret
;
3076 len
= 1 + 4; /* message type, bit count */
3077 len
+= ssh1_bignum_length(s
->key
.exponent
);
3078 len
+= ssh1_bignum_length(s
->key
.modulus
);
3079 len
+= ssh1_bignum_length(s
->challenge
);
3080 len
+= 16; /* session id */
3081 len
+= 4; /* response format */
3082 agentreq
= snewn(4 + len
, char);
3083 PUT_32BIT(agentreq
, len
);
3085 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
3086 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
3088 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
3089 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
3090 q
+= ssh1_write_bignum(q
, s
->challenge
);
3091 memcpy(q
, s
->session_id
, 16);
3093 PUT_32BIT(q
, 1); /* response format */
3094 if (!agent_query(agentreq
, len
+ 4, &vret
, &retlen
,
3095 ssh_agent_callback
, ssh
)) {
3100 bombout(("Unexpected data from server"
3101 " while waiting for agent"
3105 } while (pktin
|| inlen
> 0);
3106 vret
= ssh
->agent_response
;
3107 retlen
= ssh
->agent_response_len
;
3112 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
3113 logevent("Sending Pageant's response");
3114 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3115 PKT_DATA
, ret
+ 5, 16,
3119 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
3121 ("Pageant's response accepted");
3122 if (flags
& FLAG_VERBOSE
) {
3123 c_write_str(ssh
, "Authenticated using"
3125 c_write(ssh
, s
->commentp
,
3127 c_write_str(ssh
, "\" from agent\r\n");
3132 ("Pageant's response not accepted");
3135 ("Pageant failed to answer challenge");
3139 logevent("No reply received from Pageant");
3142 freebn(s
->key
.exponent
);
3143 freebn(s
->key
.modulus
);
3144 freebn(s
->challenge
);
3153 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
3154 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
3156 if (ssh
->cfg
.try_tis_auth
&&
3157 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
3158 !s
->tis_auth_refused
) {
3159 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
3160 logevent("Requested TIS authentication");
3161 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
3163 if (pktin
->type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
3164 logevent("TIS authentication declined");
3165 if (flags
& FLAG_INTERACTIVE
)
3166 c_write_str(ssh
, "TIS authentication refused.\r\n");
3167 s
->tis_auth_refused
= 1;
3173 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3175 bombout(("TIS challenge packet was badly formed"));
3178 logevent("Received TIS challenge");
3179 if (challengelen
> sizeof(s
->prompt
) - 1)
3180 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3181 memcpy(s
->prompt
, challenge
, challengelen
);
3182 /* Prompt heuristic comes from OpenSSH */
3183 strncpy(s
->prompt
+ challengelen
,
3184 memchr(s
->prompt
, '\n', challengelen
) ?
3185 "": "\r\nResponse: ",
3186 (sizeof s
->prompt
) - challengelen
);
3187 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
3190 if (ssh
->cfg
.try_tis_auth
&&
3191 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
3192 !s
->ccard_auth_refused
) {
3193 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
3194 logevent("Requested CryptoCard authentication");
3195 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
3197 if (pktin
->type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
3198 logevent("CryptoCard authentication declined");
3199 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
3200 s
->ccard_auth_refused
= 1;
3206 ssh_pkt_getstring(pktin
, &challenge
, &challengelen
);
3208 bombout(("CryptoCard challenge packet was badly formed"));
3211 logevent("Received CryptoCard challenge");
3212 if (challengelen
> sizeof(s
->prompt
) - 1)
3213 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
3214 memcpy(s
->prompt
, challenge
, challengelen
);
3215 strncpy(s
->prompt
+ challengelen
,
3216 memchr(s
->prompt
, '\n', challengelen
) ?
3217 "" : "\r\nResponse: ",
3218 sizeof(s
->prompt
) - challengelen
);
3219 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
3222 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3223 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
3224 s
->username
, ssh
->savedhost
);
3226 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3227 char *comment
= NULL
;
3230 if (flags
& FLAG_VERBOSE
)
3231 c_write_str(ssh
, "Trying public key authentication.\r\n");
3232 logeventf(ssh
, "Trying public key \"%s\"",
3233 filename_to_str(&ssh
->cfg
.keyfile
));
3234 type
= key_type(&ssh
->cfg
.keyfile
);
3235 if (type
!= SSH_KEYTYPE_SSH1
) {
3236 sprintf(msgbuf
, "Key is of wrong type (%s)",
3237 key_type_to_str(type
));
3239 c_write_str(ssh
, msgbuf
);
3240 c_write_str(ssh
, "\r\n");
3241 s
->tried_publickey
= 1;
3244 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
3245 if (flags
& FLAG_VERBOSE
)
3246 c_write_str(ssh
, "No passphrase required.\r\n");
3249 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
3254 * Show password prompt, having first obtained it via a TIS
3255 * or CryptoCard exchange if we're doing TIS or CryptoCard
3259 if (!ssh_get_line(s
->prompt
, s
->password
,
3260 sizeof(s
->password
), TRUE
)) {
3262 * get_line failed to get a password (for example
3263 * because one was supplied on the command line
3264 * which has already failed to work). Terminate.
3266 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
3267 PKT_STR
, "No more passwords available to try",
3269 logevent("Unable to authenticate");
3270 connection_fatal(ssh
->frontend
, "Unable to authenticate");
3271 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
3275 /* Prompt may have come from server. We've munged it a bit, so
3276 * we know it to be zero-terminated at least once. */
3277 int ret
; /* need not be saved over crReturn */
3278 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
3281 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
3283 crWaitUntil(!pktin
);
3284 ret
= process_userpass_input(ssh
, in
, inlen
);
3288 c_write_str(ssh
, "\r\n");
3292 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
3294 * Try public key authentication with the specified
3297 s
->tried_publickey
= 1;
3300 const char *error
= NULL
;
3301 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
,
3304 c_write_str(ssh
, "Couldn't load private key from ");
3305 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
3306 c_write_str(ssh
, " (");
3307 c_write_str(ssh
, error
);
3308 c_write_str(ssh
, ").\r\n");
3309 continue; /* go and try password */
3312 c_write_str(ssh
, "Wrong passphrase.\r\n");
3313 s
->tried_publickey
= 0;
3314 continue; /* try again */
3319 * Send a public key attempt.
3321 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
3322 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
3325 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3326 c_write_str(ssh
, "Server refused our public key.\r\n");
3327 continue; /* go and try password */
3329 if (pktin
->type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
3330 bombout(("Bizarre response to offer of public key"));
3336 unsigned char buffer
[32];
3337 Bignum challenge
, response
;
3339 if ((challenge
= ssh1_pkt_getmp(pktin
)) == NULL
) {
3340 bombout(("Server's RSA challenge was badly formatted"));
3343 response
= rsadecrypt(challenge
, &s
->key
);
3344 freebn(s
->key
.private_exponent
);/* burn the evidence */
3346 for (i
= 0; i
< 32; i
++) {
3347 buffer
[i
] = bignum_byte(response
, 31 - i
);
3351 MD5Update(&md5c
, buffer
, 32);
3352 MD5Update(&md5c
, s
->session_id
, 16);
3353 MD5Final(buffer
, &md5c
);
3355 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
3356 PKT_DATA
, buffer
, 16, PKT_END
);
3363 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3364 if (flags
& FLAG_VERBOSE
)
3365 c_write_str(ssh
, "Failed to authenticate with"
3366 " our public key.\r\n");
3367 continue; /* go and try password */
3368 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3369 bombout(("Bizarre response to RSA authentication response"));
3373 break; /* we're through! */
3375 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
3377 * Defence against traffic analysis: we send a
3378 * whole bunch of packets containing strings of
3379 * different lengths. One of these strings is the
3380 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3381 * The others are all random data in
3382 * SSH1_MSG_IGNORE packets. This way a passive
3383 * listener can't tell which is the password, and
3384 * hence can't deduce the password length.
3386 * Anybody with a password length greater than 16
3387 * bytes is going to have enough entropy in their
3388 * password that a listener won't find it _that_
3389 * much help to know how long it is. So what we'll
3392 * - if password length < 16, we send 15 packets
3393 * containing string lengths 1 through 15
3395 * - otherwise, we let N be the nearest multiple
3396 * of 8 below the password length, and send 8
3397 * packets containing string lengths N through
3398 * N+7. This won't obscure the order of
3399 * magnitude of the password length, but it will
3400 * introduce a bit of extra uncertainty.
3402 * A few servers (the old 1.2.18 through 1.2.22)
3403 * can't deal with SSH1_MSG_IGNORE. For these
3404 * servers, we need an alternative defence. We make
3405 * use of the fact that the password is interpreted
3406 * as a C string: so we can append a NUL, then some
3409 * One server (a Cisco one) can deal with neither
3410 * SSH1_MSG_IGNORE _nor_ a padded password string.
3411 * For this server we are left with no defences
3412 * against password length sniffing.
3414 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
3416 * The server can deal with SSH1_MSG_IGNORE, so
3417 * we can use the primary defence.
3419 int bottom
, top
, pwlen
, i
;
3422 pwlen
= strlen(s
->password
);
3424 bottom
= 0; /* zero length passwords are OK! :-) */
3427 bottom
= pwlen
& ~7;
3431 assert(pwlen
>= bottom
&& pwlen
<= top
);
3433 randomstr
= snewn(top
+ 1, char);
3435 for (i
= bottom
; i
<= top
; i
++) {
3437 defer_packet(ssh
, s
->pwpkt_type
,
3438 PKTT_PASSWORD
, PKT_STR
, s
->password
,
3439 PKTT_OTHER
, PKT_END
);
3441 for (j
= 0; j
< i
; j
++) {
3443 randomstr
[j
] = random_byte();
3444 } while (randomstr
[j
] == '\0');
3446 randomstr
[i
] = '\0';
3447 defer_packet(ssh
, SSH1_MSG_IGNORE
,
3448 PKT_STR
, randomstr
, PKT_END
);
3451 logevent("Sending password with camouflage packets");
3452 ssh_pkt_defersend(ssh
);
3455 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
3457 * The server can't deal with SSH1_MSG_IGNORE
3458 * but can deal with padded passwords, so we
3459 * can use the secondary defence.
3465 len
= strlen(s
->password
);
3466 if (len
< sizeof(string
)) {
3468 strcpy(string
, s
->password
);
3469 len
++; /* cover the zero byte */
3470 while (len
< sizeof(string
)) {
3471 string
[len
++] = (char) random_byte();
3476 logevent("Sending length-padded password");
3477 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3478 PKT_INT
, len
, PKT_DATA
, ss
, len
,
3479 PKTT_OTHER
, PKT_END
);
3482 * The server has _both_
3483 * BUG_CHOKES_ON_SSH1_IGNORE and
3484 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3485 * therefore nothing we can do.
3488 len
= strlen(s
->password
);
3489 logevent("Sending unpadded password");
3490 send_packet(ssh
, s
->pwpkt_type
,
3491 PKTT_PASSWORD
, PKT_INT
, len
,
3492 PKT_DATA
, s
->password
, len
,
3493 PKTT_OTHER
, PKT_END
);
3496 send_packet(ssh
, s
->pwpkt_type
, PKTT_PASSWORD
,
3497 PKT_STR
, s
->password
, PKTT_OTHER
, PKT_END
);
3500 logevent("Sent password");
3501 memset(s
->password
, 0, strlen(s
->password
));
3503 if (pktin
->type
== SSH1_SMSG_FAILURE
) {
3504 if (flags
& FLAG_VERBOSE
)
3505 c_write_str(ssh
, "Access denied\r\n");
3506 logevent("Authentication refused");
3507 } else if (pktin
->type
!= SSH1_SMSG_SUCCESS
) {
3508 bombout(("Strange packet received, type %d", pktin
->type
));
3513 logevent("Authentication successful");
3518 void sshfwd_close(struct ssh_channel
*c
)
3522 if (ssh
->state
!= SSH_STATE_SESSION
) {
3523 assert(ssh
->state
== SSH_STATE_CLOSED
);
3527 if (c
&& !c
->closes
) {
3529 * If the channel's remoteid is -1, we have sent
3530 * CHANNEL_OPEN for this channel, but it hasn't even been
3531 * acknowledged by the server. So we must set a close flag
3532 * on it now, and then when the server acks the channel
3533 * open, we can close it then.
3535 if (((int)c
->remoteid
) != -1) {
3536 if (ssh
->version
== 1) {
3537 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
3540 struct Packet
*pktout
;
3541 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3542 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
3543 ssh2_pkt_send(ssh
, pktout
);
3546 c
->closes
= 1; /* sent MSG_CLOSE */
3547 if (c
->type
== CHAN_X11
) {
3549 logevent("Forwarded X11 connection terminated");
3550 } else if (c
->type
== CHAN_SOCKDATA
||
3551 c
->type
== CHAN_SOCKDATA_DORMANT
) {
3553 logevent("Forwarded port closed");
3558 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3562 if (ssh
->state
!= SSH_STATE_SESSION
) {
3563 assert(ssh
->state
== SSH_STATE_CLOSED
);
3567 if (ssh
->version
== 1) {
3568 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3569 PKT_INT
, c
->remoteid
,
3571 PKT_INT
, len
, PKT_DATA
, buf
, len
,
3572 PKTT_OTHER
, PKT_END
);
3574 * In SSH1 we can return 0 here - implying that forwarded
3575 * connections are never individually throttled - because
3576 * the only circumstance that can cause throttling will be
3577 * the whole SSH connection backing up, in which case
3578 * _everything_ will be throttled as a whole.
3582 ssh2_add_channel_data(c
, buf
, len
);
3583 return ssh2_try_send(c
);
3587 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3591 if (ssh
->state
!= SSH_STATE_SESSION
) {
3592 assert(ssh
->state
== SSH_STATE_CLOSED
);
3596 if (ssh
->version
== 1) {
3597 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3598 c
->v
.v1
.throttling
= 0;
3599 ssh1_throttle(ssh
, -1);
3602 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3606 static void ssh_queueing_handler(Ssh ssh
, struct Packet
*pktin
)
3608 struct queued_handler
*qh
= ssh
->qhead
;
3612 assert(pktin
->type
== qh
->msg1
|| pktin
->type
== qh
->msg2
);
3615 assert(ssh
->packet_dispatch
[qh
->msg1
] == ssh_queueing_handler
);
3616 ssh
->packet_dispatch
[qh
->msg1
] = NULL
;
3619 assert(ssh
->packet_dispatch
[qh
->msg2
] == ssh_queueing_handler
);
3620 ssh
->packet_dispatch
[qh
->msg2
] = NULL
;
3624 ssh
->qhead
= qh
->next
;
3626 if (ssh
->qhead
->msg1
> 0) {
3627 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg1
] == NULL
);
3628 ssh
->packet_dispatch
[ssh
->qhead
->msg1
] = ssh_queueing_handler
;
3630 if (ssh
->qhead
->msg2
> 0) {
3631 assert(ssh
->packet_dispatch
[ssh
->qhead
->msg2
] == NULL
);
3632 ssh
->packet_dispatch
[ssh
->qhead
->msg2
] = ssh_queueing_handler
;
3635 ssh
->qhead
= ssh
->qtail
= NULL
;
3636 ssh
->packet_dispatch
[pktin
->type
] = NULL
;
3639 qh
->handler(ssh
, pktin
, qh
->ctx
);
3644 static void ssh_queue_handler(Ssh ssh
, int msg1
, int msg2
,
3645 chandler_fn_t handler
, void *ctx
)
3647 struct queued_handler
*qh
;
3649 qh
= snew(struct queued_handler
);
3652 qh
->handler
= handler
;
3656 if (ssh
->qtail
== NULL
) {
3660 assert(ssh
->packet_dispatch
[qh
->msg1
] == NULL
);
3661 ssh
->packet_dispatch
[qh
->msg1
] = ssh_queueing_handler
;
3664 assert(ssh
->packet_dispatch
[qh
->msg2
] == NULL
);
3665 ssh
->packet_dispatch
[qh
->msg2
] = ssh_queueing_handler
;
3668 ssh
->qtail
->next
= qh
;
3673 static void ssh_rportfwd_succfail(Ssh ssh
, struct Packet
*pktin
, void *ctx
)
3675 struct ssh_rportfwd
*rpf
, *pf
= (struct ssh_rportfwd
*)ctx
;
3677 if (pktin
->type
== (ssh
->version
== 1 ? SSH1_SMSG_SUCCESS
:
3678 SSH2_MSG_REQUEST_SUCCESS
)) {
3679 logeventf(ssh
, "Remote port forwarding from %s enabled",
3682 logeventf(ssh
, "Remote port forwarding from %s refused",
3685 rpf
= del234(ssh
->rportfwds
, pf
);
3691 static void ssh_setup_portfwd(Ssh ssh
, const Config
*cfg
)
3693 const char *portfwd_strptr
= cfg
->portfwd
;
3694 struct ssh_portfwd
*epf
;
3697 if (!ssh
->portfwds
) {
3698 ssh
->portfwds
= newtree234(ssh_portcmp
);
3701 * Go through the existing port forwardings and tag them
3702 * with status==DESTROY. Any that we want to keep will be
3703 * re-enabled (status==KEEP) as we go through the
3704 * configuration and find out which bits are the same as
3707 struct ssh_portfwd
*epf
;
3709 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3710 epf
->status
= DESTROY
;
3713 while (*portfwd_strptr
) {
3714 char address_family
, type
;
3715 int sport
,dport
,sserv
,dserv
;
3716 char sports
[256], dports
[256], saddr
[256], host
[256];
3719 address_family
= 'A';
3721 if (*portfwd_strptr
== 'A' ||
3722 *portfwd_strptr
== '4' ||
3723 *portfwd_strptr
== '6')
3724 address_family
= *portfwd_strptr
++;
3725 if (*portfwd_strptr
== 'L' ||
3726 *portfwd_strptr
== 'R' ||
3727 *portfwd_strptr
== 'D')
3728 type
= *portfwd_strptr
++;
3733 while (*portfwd_strptr
&& *portfwd_strptr
!= '\t') {
3734 if (*portfwd_strptr
== ':') {
3736 * We've seen a colon in the middle of the
3737 * source port number. This means that
3738 * everything we've seen until now is the
3739 * source _address_, so we'll move it into
3740 * saddr and start sports from the beginning
3745 if (ssh
->version
== 1 && type
== 'R') {
3746 logeventf(ssh
, "SSH1 cannot handle remote source address "
3747 "spec \"%s\"; ignoring", sports
);
3749 strcpy(saddr
, sports
);
3752 if (n
< 255) sports
[n
++] = *portfwd_strptr
++;
3756 if (*portfwd_strptr
== '\t')
3759 while (*portfwd_strptr
&& *portfwd_strptr
!= ':') {
3760 if (n
< 255) host
[n
++] = *portfwd_strptr
++;
3763 if (*portfwd_strptr
== ':')
3766 while (*portfwd_strptr
) {
3767 if (n
< 255) dports
[n
++] = *portfwd_strptr
++;
3771 dport
= atoi(dports
);
3775 dport
= net_service_lookup(dports
);
3777 logeventf(ssh
, "Service lookup failed for destination"
3778 " port \"%s\"", dports
);
3782 while (*portfwd_strptr
) portfwd_strptr
++;
3784 portfwd_strptr
++; /* eat the NUL and move to next one */
3786 sport
= atoi(sports
);
3790 sport
= net_service_lookup(sports
);
3792 logeventf(ssh
, "Service lookup failed for source"
3793 " port \"%s\"", sports
);
3796 if (sport
&& dport
) {
3797 /* Set up a description of the source port. */
3798 struct ssh_portfwd
*pfrec
, *epfrec
;
3800 pfrec
= snew(struct ssh_portfwd
);
3802 pfrec
->saddr
= *saddr ?
dupstr(saddr
) : NULL
;
3803 pfrec
->sserv
= sserv ?
dupstr(sports
) : NULL
;
3804 pfrec
->sport
= sport
;
3805 pfrec
->daddr
= *host ?
dupstr(host
) : NULL
;
3806 pfrec
->dserv
= dserv ?
dupstr(dports
) : NULL
;
3807 pfrec
->dport
= dport
;
3808 pfrec
->local
= NULL
;
3809 pfrec
->remote
= NULL
;
3810 pfrec
->addressfamily
= (address_family
== '4' ? ADDRTYPE_IPV4
:
3811 address_family
== '6' ? ADDRTYPE_IPV6
:
3814 epfrec
= add234(ssh
->portfwds
, pfrec
);
3815 if (epfrec
!= pfrec
) {
3817 * We already have a port forwarding with precisely
3818 * these parameters. Hence, no need to do anything;
3819 * simply tag the existing one as KEEP.
3821 epfrec
->status
= KEEP
;
3822 free_portfwd(pfrec
);
3824 pfrec
->status
= CREATE
;
3830 * Now go through and destroy any port forwardings which were
3833 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3834 if (epf
->status
== DESTROY
) {
3837 message
= dupprintf("%s port forwarding from %s%s%d",
3838 epf
->type
== 'L' ?
"local" :
3839 epf
->type
== 'R' ?
"remote" : "dynamic",
3840 epf
->saddr ? epf
->saddr
: "",
3841 epf
->saddr ?
":" : "",
3844 if (epf
->type
!= 'D') {
3845 char *msg2
= dupprintf("%s to %s:%d", message
,
3846 epf
->daddr
, epf
->dport
);
3851 logeventf(ssh
, "Cancelling %s", message
);
3855 struct ssh_rportfwd
*rpf
= epf
->remote
;
3856 struct Packet
*pktout
;
3859 * Cancel the port forwarding at the server
3862 if (ssh
->version
== 1) {
3864 * We cannot cancel listening ports on the
3865 * server side in SSH1! There's no message
3866 * to support it. Instead, we simply remove
3867 * the rportfwd record from the local end
3868 * so that any connections the server tries
3869 * to make on it are rejected.
3872 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3873 ssh2_pkt_addstring(pktout
, "cancel-tcpip-forward");
3874 ssh2_pkt_addbool(pktout
, 0);/* _don't_ want reply */
3876 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3877 } else if (ssh
->cfg
.rport_acceptall
) {
3878 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3880 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3882 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3883 ssh2_pkt_send(ssh
, pktout
);
3886 del234(ssh
->rportfwds
, rpf
);
3888 } else if (epf
->local
) {
3889 pfd_terminate(epf
->local
);
3892 delpos234(ssh
->portfwds
, i
);
3894 i
--; /* so we don't skip one in the list */
3898 * And finally, set up any new port forwardings (status==CREATE).
3900 for (i
= 0; (epf
= index234(ssh
->portfwds
, i
)) != NULL
; i
++)
3901 if (epf
->status
== CREATE
) {
3902 char *sportdesc
, *dportdesc
;
3903 sportdesc
= dupprintf("%s%s%s%s%d%s",
3904 epf
->saddr ? epf
->saddr
: "",
3905 epf
->saddr ?
":" : "",
3906 epf
->sserv ? epf
->sserv
: "",
3907 epf
->sserv ?
"(" : "",
3909 epf
->sserv ?
")" : "");
3910 if (epf
->type
== 'D') {
3913 dportdesc
= dupprintf("%s:%s%s%d%s",
3915 epf
->dserv ? epf
->dserv
: "",
3916 epf
->dserv ?
"(" : "",
3918 epf
->dserv ?
")" : "");
3921 if (epf
->type
== 'L') {
3922 const char *err
= pfd_addforward(epf
->daddr
, epf
->dport
,
3923 epf
->saddr
, epf
->sport
,
3926 epf
->addressfamily
);
3928 logeventf(ssh
, "Local %sport %s forwarding to %s%s%s",
3929 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3930 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3931 sportdesc
, dportdesc
,
3932 err ?
" failed: " : "", err ? err
: "");
3933 } else if (epf
->type
== 'D') {
3934 const char *err
= pfd_addforward(NULL
, -1,
3935 epf
->saddr
, epf
->sport
,
3938 epf
->addressfamily
);
3940 logeventf(ssh
, "Local %sport %s SOCKS dynamic forwarding%s%s",
3941 epf
->addressfamily
== ADDRTYPE_IPV4 ?
"IPv4 " :
3942 epf
->addressfamily
== ADDRTYPE_IPV6 ?
"IPv6 " : "",
3944 err ?
" failed: " : "", err ? err
: "");
3946 struct ssh_rportfwd
*pf
;
3949 * Ensure the remote port forwardings tree exists.
3951 if (!ssh
->rportfwds
) {
3952 if (ssh
->version
== 1)
3953 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3955 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
3958 pf
= snew(struct ssh_rportfwd
);
3959 strncpy(pf
->dhost
, epf
->daddr
, lenof(pf
->dhost
)-1);
3960 pf
->dhost
[lenof(pf
->dhost
)-1] = '\0';
3961 pf
->dport
= epf
->dport
;
3962 pf
->sport
= epf
->sport
;
3963 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3964 logeventf(ssh
, "Duplicate remote port forwarding to %s:%d",
3965 epf
->daddr
, epf
->dport
);
3968 logeventf(ssh
, "Requesting remote port %s"
3969 " forward to %s", sportdesc
, dportdesc
);
3971 pf
->sportdesc
= sportdesc
;
3976 if (ssh
->version
== 1) {
3977 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3978 PKT_INT
, epf
->sport
,
3979 PKT_STR
, epf
->daddr
,
3980 PKT_INT
, epf
->dport
,
3982 ssh_queue_handler(ssh
, SSH1_SMSG_SUCCESS
,
3984 ssh_rportfwd_succfail
, pf
);
3986 struct Packet
*pktout
;
3987 pktout
= ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST
);
3988 ssh2_pkt_addstring(pktout
, "tcpip-forward");
3989 ssh2_pkt_addbool(pktout
, 1);/* want reply */
3991 ssh2_pkt_addstring(pktout
, epf
->saddr
);
3992 } else if (ssh
->cfg
.rport_acceptall
) {
3993 ssh2_pkt_addstring(pktout
, "0.0.0.0");
3995 ssh2_pkt_addstring(pktout
, "127.0.0.1");
3997 ssh2_pkt_adduint32(pktout
, epf
->sport
);
3998 ssh2_pkt_send(ssh
, pktout
);
4000 ssh_queue_handler(ssh
, SSH2_MSG_REQUEST_SUCCESS
,
4001 SSH2_MSG_REQUEST_FAILURE
,
4002 ssh_rportfwd_succfail
, pf
);
4011 static void ssh1_smsg_stdout_stderr_data(Ssh ssh
, struct Packet
*pktin
)
4014 int stringlen
, bufsize
;
4016 ssh_pkt_getstring(pktin
, &string
, &stringlen
);
4017 if (string
== NULL
) {
4018 bombout(("Incoming terminal data packet was badly formed"));
4022 bufsize
= from_backend(ssh
->frontend
, pktin
->type
== SSH1_SMSG_STDERR_DATA
,
4024 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4025 ssh
->v1_stdout_throttling
= 1;
4026 ssh1_throttle(ssh
, +1);
4030 static void ssh1_smsg_x11_open(Ssh ssh
, struct Packet
*pktin
)
4032 /* Remote side is trying to open a channel to talk to our
4033 * X-Server. Give them back a local channel number. */
4034 struct ssh_channel
*c
;
4035 int remoteid
= ssh_pkt_getuint32(pktin
);
4037 logevent("Received X11 connect request");
4038 /* Refuse if X11 forwarding is disabled. */
4039 if (!ssh
->X11_fwd_enabled
) {
4040 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4041 PKT_INT
, remoteid
, PKT_END
);
4042 logevent("Rejected X11 connect request");
4044 c
= snew(struct ssh_channel
);
4047 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
4048 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
4049 logevent("Opening X11 forward connection failed");
4051 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4052 PKT_INT
, remoteid
, PKT_END
);
4055 ("Opening X11 forward connection succeeded");
4056 c
->remoteid
= remoteid
;
4057 c
->localid
= alloc_channel_id(ssh
);
4059 c
->v
.v1
.throttling
= 0;
4060 c
->type
= CHAN_X11
; /* identify channel type */
4061 add234(ssh
->channels
, c
);
4062 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4063 PKT_INT
, c
->remoteid
, PKT_INT
,
4064 c
->localid
, PKT_END
);
4065 logevent("Opened X11 forward channel");
4070 static void ssh1_smsg_agent_open(Ssh ssh
, struct Packet
*pktin
)
4072 /* Remote side is trying to open a channel to talk to our
4073 * agent. Give them back a local channel number. */
4074 struct ssh_channel
*c
;
4075 int remoteid
= ssh_pkt_getuint32(pktin
);
4077 /* Refuse if agent forwarding is disabled. */
4078 if (!ssh
->agentfwd_enabled
) {
4079 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4080 PKT_INT
, remoteid
, PKT_END
);
4082 c
= snew(struct ssh_channel
);
4084 c
->remoteid
= remoteid
;
4085 c
->localid
= alloc_channel_id(ssh
);
4087 c
->v
.v1
.throttling
= 0;
4088 c
->type
= CHAN_AGENT
; /* identify channel type */
4089 c
->u
.a
.lensofar
= 0;
4090 add234(ssh
->channels
, c
);
4091 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4092 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
4097 static void ssh1_msg_port_open(Ssh ssh
, struct Packet
*pktin
)
4099 /* Remote side is trying to open a channel to talk to a
4100 * forwarded port. Give them back a local channel number. */
4101 struct ssh_channel
*c
;
4102 struct ssh_rportfwd pf
, *pfp
;
4105 char *host
, buf
[1024];
4107 c
= snew(struct ssh_channel
);
4110 remoteid
= ssh_pkt_getuint32(pktin
);
4111 ssh_pkt_getstring(pktin
, &host
, &hostsize
);
4112 port
= ssh_pkt_getuint32(pktin
);
4114 if (hostsize
>= lenof(pf
.dhost
))
4115 hostsize
= lenof(pf
.dhost
)-1;
4116 memcpy(pf
.dhost
, host
, hostsize
);
4117 pf
.dhost
[hostsize
] = '\0';
4119 pfp
= find234(ssh
->rportfwds
, &pf
, NULL
);
4122 sprintf(buf
, "Rejected remote port open request for %s:%d",
4125 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4126 PKT_INT
, remoteid
, PKT_END
);
4128 sprintf(buf
, "Received remote port open request for %s:%d",
4131 e
= pfd_newconnect(&c
->u
.pfd
.s
, pf
.dhost
, port
,
4132 c
, &ssh
->cfg
, pfp
->pfrec
->addressfamily
);
4135 sprintf(buf
, "Port open failed: %s", e
);
4138 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
4139 PKT_INT
, remoteid
, PKT_END
);
4141 c
->remoteid
= remoteid
;
4142 c
->localid
= alloc_channel_id(ssh
);
4144 c
->v
.v1
.throttling
= 0;
4145 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
4146 add234(ssh
->channels
, c
);
4147 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
4148 PKT_INT
, c
->remoteid
, PKT_INT
,
4149 c
->localid
, PKT_END
);
4150 logevent("Forwarded port opened successfully");
4155 static void ssh1_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
4157 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4158 unsigned int localid
= ssh_pkt_getuint32(pktin
);
4159 struct ssh_channel
*c
;
4161 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4162 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4163 c
->remoteid
= localid
;
4164 c
->type
= CHAN_SOCKDATA
;
4165 c
->v
.v1
.throttling
= 0;
4166 pfd_confirm(c
->u
.pfd
.s
);
4169 if (c
&& c
->closes
) {
4171 * We have a pending close on this channel,
4172 * which we decided on before the server acked
4173 * the channel open. So now we know the
4174 * remoteid, we can close it again.
4176 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
4177 PKT_INT
, c
->remoteid
, PKT_END
);
4181 static void ssh1_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
4183 unsigned int remoteid
= ssh_pkt_getuint32(pktin
);
4184 struct ssh_channel
*c
;
4186 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
4187 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
4188 logevent("Forwarded connection refused by server");
4189 pfd_close(c
->u
.pfd
.s
);
4190 del234(ssh
->channels
, c
);
4195 static void ssh1_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
4197 /* Remote side closes a channel. */
4198 unsigned i
= ssh_pkt_getuint32(pktin
);
4199 struct ssh_channel
*c
;
4200 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4201 if (c
&& ((int)c
->remoteid
) != -1) {
4204 (pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
4206 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
4207 logevent("Forwarded X11 connection terminated");
4208 assert(c
->u
.x11
.s
!= NULL
);
4209 x11_close(c
->u
.x11
.s
);
4212 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
4213 logevent("Forwarded port closed");
4214 assert(c
->u
.pfd
.s
!= NULL
);
4215 pfd_close(c
->u
.pfd
.s
);
4219 c
->closes
|= (closetype
<< 2); /* seen this message */
4220 if (!(c
->closes
& closetype
)) {
4221 send_packet(ssh
, pktin
->type
, PKT_INT
, c
->remoteid
,
4223 c
->closes
|= closetype
; /* sent it too */
4226 if (c
->closes
== 15) {
4227 del234(ssh
->channels
, c
);
4231 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4232 pktin
->type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
4233 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
4238 static void ssh1_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
4240 /* Data sent down one of our channels. */
4241 int i
= ssh_pkt_getuint32(pktin
);
4244 struct ssh_channel
*c
;
4246 ssh_pkt_getstring(pktin
, &p
, &len
);
4248 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
4253 bufsize
= x11_send(c
->u
.x11
.s
, p
, len
);
4256 bufsize
= pfd_send(c
->u
.pfd
.s
, p
, len
);
4259 /* Data for an agent message. Buffer it. */
4261 if (c
->u
.a
.lensofar
< 4) {
4262 unsigned int l
= min(4 - c
->u
.a
.lensofar
, len
);
4263 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
4267 c
->u
.a
.lensofar
+= l
;
4269 if (c
->u
.a
.lensofar
== 4) {
4271 4 + GET_32BIT(c
->u
.a
.msglen
);
4272 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
4274 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
4276 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
4278 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
4280 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
4284 c
->u
.a
.lensofar
+= l
;
4286 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
4289 if (agent_query(c
->u
.a
.message
,
4292 ssh_agentf_callback
, c
))
4293 ssh_agentf_callback(c
, reply
, replylen
);
4294 sfree(c
->u
.a
.message
);
4295 c
->u
.a
.lensofar
= 0;
4298 bufsize
= 0; /* agent channels never back up */
4301 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
4302 c
->v
.v1
.throttling
= 1;
4303 ssh1_throttle(ssh
, +1);
4308 static void ssh1_smsg_exit_status(Ssh ssh
, struct Packet
*pktin
)
4311 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
4312 sprintf(buf
, "Server sent command exit status %d",
4315 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
4317 * In case `helpful' firewalls or proxies tack
4318 * extra human-readable text on the end of the
4319 * session which we might mistake for another
4320 * encrypted packet, we close the session once
4321 * we've sent EXIT_CONFIRMATION.
4323 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
4326 static void do_ssh1_connection(Ssh ssh
, unsigned char *in
, int inlen
,
4327 struct Packet
*pktin
)
4329 crBegin(ssh
->do_ssh1_connection_crstate
);
4331 ssh
->packet_dispatch
[SSH1_SMSG_STDOUT_DATA
] =
4332 ssh
->packet_dispatch
[SSH1_SMSG_STDERR_DATA
] =
4333 ssh1_smsg_stdout_stderr_data
;
4335 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
] =
4336 ssh1_msg_channel_open_confirmation
;
4337 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_OPEN_FAILURE
] =
4338 ssh1_msg_channel_open_failure
;
4339 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE
] =
4340 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
] =
4341 ssh1_msg_channel_close
;
4342 ssh
->packet_dispatch
[SSH1_MSG_CHANNEL_DATA
] = ssh1_msg_channel_data
;
4343 ssh
->packet_dispatch
[SSH1_SMSG_EXIT_STATUS
] = ssh1_smsg_exit_status
;
4345 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
4346 logevent("Requesting agent forwarding");
4347 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
4351 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4352 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4353 bombout(("Protocol confusion"));
4355 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4356 logevent("Agent forwarding refused");
4358 logevent("Agent forwarding enabled");
4359 ssh
->agentfwd_enabled
= TRUE
;
4360 ssh
->packet_dispatch
[SSH1_SMSG_AGENT_OPEN
] = ssh1_smsg_agent_open
;
4364 if (ssh
->cfg
.x11_forward
) {
4365 char proto
[20], data
[64];
4366 logevent("Requesting X11 forwarding");
4367 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
4368 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
4369 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
4370 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
4371 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4372 PKT_STR
, proto
, PKT_STR
, data
,
4373 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
4376 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
4377 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
4382 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4383 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4384 bombout(("Protocol confusion"));
4386 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4387 logevent("X11 forwarding refused");
4389 logevent("X11 forwarding enabled");
4390 ssh
->X11_fwd_enabled
= TRUE
;
4391 ssh
->packet_dispatch
[SSH1_SMSG_X11_OPEN
] = ssh1_smsg_x11_open
;
4395 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
4396 ssh
->packet_dispatch
[SSH1_MSG_PORT_OPEN
] = ssh1_msg_port_open
;
4398 if (!ssh
->cfg
.nopty
) {
4399 /* Unpick the terminal-speed string. */
4400 /* XXX perhaps we should allow no speeds to be sent. */
4401 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
4402 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
4403 /* Send the pty request. */
4404 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
4405 PKT_STR
, ssh
->cfg
.termtype
,
4406 PKT_INT
, ssh
->term_height
,
4407 PKT_INT
, ssh
->term_width
,
4408 PKT_INT
, 0, PKT_INT
, 0, /* width,height in pixels */
4409 PKT_CHAR
, 192, PKT_INT
, ssh
->ispeed
, /* TTY_OP_ISPEED */
4410 PKT_CHAR
, 193, PKT_INT
, ssh
->ospeed
, /* TTY_OP_OSPEED */
4411 PKT_CHAR
, 0, PKT_END
);
4412 ssh
->state
= SSH_STATE_INTERMED
;
4416 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4417 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4418 bombout(("Protocol confusion"));
4420 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4421 c_write_str(ssh
, "Server refused to allocate pty\r\n");
4422 ssh
->editing
= ssh
->echoing
= 1;
4424 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
4425 ssh
->ospeed
, ssh
->ispeed
);
4427 ssh
->editing
= ssh
->echoing
= 1;
4430 if (ssh
->cfg
.compression
) {
4431 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
4435 if (pktin
->type
!= SSH1_SMSG_SUCCESS
4436 && pktin
->type
!= SSH1_SMSG_FAILURE
) {
4437 bombout(("Protocol confusion"));
4439 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4440 c_write_str(ssh
, "Server refused to compress\r\n");
4442 logevent("Started compression");
4443 ssh
->v1_compressing
= TRUE
;
4444 ssh
->cs_comp_ctx
= zlib_compress_init();
4445 logevent("Initialised zlib (RFC1950) compression");
4446 ssh
->sc_comp_ctx
= zlib_decompress_init();
4447 logevent("Initialised zlib (RFC1950) decompression");
4451 * Start the shell or command.
4453 * Special case: if the first-choice command is an SSH2
4454 * subsystem (hence not usable here) and the second choice
4455 * exists, we fall straight back to that.
4458 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
4460 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
4461 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
4462 ssh
->fallback_cmd
= TRUE
;
4465 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
4467 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
4468 logevent("Started session");
4471 ssh
->state
= SSH_STATE_SESSION
;
4472 if (ssh
->size_needed
)
4473 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
4474 if (ssh
->eof_needed
)
4475 ssh_special(ssh
, TS_EOF
);
4478 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
4480 ssh
->channels
= newtree234(ssh_channelcmp
);
4484 * By this point, most incoming packets are already being
4485 * handled by the dispatch table, and we need only pay
4486 * attention to the unusual ones.
4491 if (pktin
->type
== SSH1_SMSG_SUCCESS
) {
4492 /* may be from EXEC_SHELL on some servers */
4493 } else if (pktin
->type
== SSH1_SMSG_FAILURE
) {
4494 /* may be from EXEC_SHELL on some servers
4495 * if no pty is available or in other odd cases. Ignore */
4497 bombout(("Strange packet received: type %d", pktin
->type
));
4502 int len
= min(inlen
, 512);
4503 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
, PKTT_DATA
,
4504 PKT_INT
, len
, PKT_DATA
, in
, len
,
4505 PKTT_OTHER
, PKT_END
);
4516 * Handle the top-level SSH2 protocol.
4518 static void ssh1_msg_debug(Ssh ssh
, struct Packet
*pktin
)
4523 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4524 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
4529 static void ssh1_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
4531 /* log reason code in disconnect message */
4535 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
4536 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen
, msg
));
4539 void ssh_msg_ignore(Ssh ssh
, struct Packet
*pktin
)
4541 /* Do nothing, because we're ignoring it! Duhh. */
4544 static void ssh1_protocol_setup(Ssh ssh
)
4549 * Most messages are handled by the coroutines.
4551 for (i
= 0; i
< 256; i
++)
4552 ssh
->packet_dispatch
[i
] = NULL
;
4555 * These special message types we install handlers for.
4557 ssh
->packet_dispatch
[SSH1_MSG_DISCONNECT
] = ssh1_msg_disconnect
;
4558 ssh
->packet_dispatch
[SSH1_MSG_IGNORE
] = ssh_msg_ignore
;
4559 ssh
->packet_dispatch
[SSH1_MSG_DEBUG
] = ssh1_msg_debug
;
4562 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
4563 struct Packet
*pktin
)
4565 if (ssh
->state
== SSH_STATE_CLOSED
)
4568 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
4569 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
4573 if (!ssh
->protocol_initial_phase_done
) {
4574 if (do_ssh1_login(ssh
, in
, inlen
, pktin
))
4575 ssh
->protocol_initial_phase_done
= TRUE
;
4580 do_ssh1_connection(ssh
, in
, inlen
, pktin
);
4584 * Utility routine for decoding comma-separated strings in KEXINIT.
4586 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
4589 if (!needle
|| !haystack
) /* protect against null pointers */
4591 needlen
= strlen(needle
);
4594 * Is it at the start of the string?
4596 if (haylen
>= needlen
&& /* haystack is long enough */
4597 !memcmp(needle
, haystack
, needlen
) && /* initial match */
4598 (haylen
== needlen
|| haystack
[needlen
] == ',')
4599 /* either , or EOS follows */
4603 * If not, search for the next comma and resume after that.
4604 * If no comma found, terminate.
4606 while (haylen
> 0 && *haystack
!= ',')
4607 haylen
--, haystack
++;
4610 haylen
--, haystack
++; /* skip over comma itself */
4615 * SSH2 key creation method.
4617 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
4618 unsigned char *sessid
, char chr
,
4619 unsigned char *keyspace
)
4622 /* First 20 bytes. */
4624 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4626 SHA_Bytes(&s
, H
, 20);
4627 SHA_Bytes(&s
, &chr
, 1);
4628 SHA_Bytes(&s
, sessid
, 20);
4629 SHA_Final(&s
, keyspace
);
4630 /* Next 20 bytes. */
4632 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
4634 SHA_Bytes(&s
, H
, 20);
4635 SHA_Bytes(&s
, keyspace
, 20);
4636 SHA_Final(&s
, keyspace
+ 20);
4640 * Handle the SSH2 transport layer.
4642 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
,
4643 struct Packet
*pktin
)
4645 struct do_ssh2_transport_state
{
4646 int nbits
, pbits
, warn
;
4647 Bignum p
, g
, e
, f
, K
;
4648 int kex_init_value
, kex_reply_value
;
4649 const struct ssh_mac
**maclist
;
4651 const struct ssh2_cipher
*cscipher_tobe
;
4652 const struct ssh2_cipher
*sccipher_tobe
;
4653 const struct ssh_mac
*csmac_tobe
;
4654 const struct ssh_mac
*scmac_tobe
;
4655 const struct ssh_compress
*cscomp_tobe
;
4656 const struct ssh_compress
*sccomp_tobe
;
4657 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
4658 int hostkeylen
, siglen
;
4659 void *hkey
; /* actual host key */
4660 unsigned char exchange_hash
[20];
4661 int n_preferred_kex
;
4662 const struct ssh_kex
*preferred_kex
[KEX_MAX
];
4663 int n_preferred_ciphers
;
4664 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
4665 const struct ssh_compress
*preferred_comp
;
4666 int got_session_id
, activated_authconn
;
4667 struct Packet
*pktout
;
4669 crState(do_ssh2_transport_state
);
4671 crBegin(ssh
->do_ssh2_transport_crstate
);
4673 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
4674 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
4675 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
4677 s
->got_session_id
= s
->activated_authconn
= FALSE
;
4680 * Be prepared to work around the buggy MAC problem.
4682 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
4683 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
4685 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
4688 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_KEX_MASK
;
4690 int i
, j
, commalist_started
;
4693 * Set up the preferred key exchange. (NULL => warn below here)
4695 s
->n_preferred_kex
= 0;
4696 for (i
= 0; i
< KEX_MAX
; i
++) {
4697 switch (ssh
->cfg
.ssh_kexlist
[i
]) {
4699 s
->preferred_kex
[s
->n_preferred_kex
++] =
4700 &ssh_diffiehellman_gex
;
4703 s
->preferred_kex
[s
->n_preferred_kex
++] =
4704 &ssh_diffiehellman_group14
;
4707 s
->preferred_kex
[s
->n_preferred_kex
++] =
4708 &ssh_diffiehellman_group1
;
4711 /* Flag for later. Don't bother if it's the last in
4713 if (i
< KEX_MAX
- 1) {
4714 s
->preferred_kex
[s
->n_preferred_kex
++] = NULL
;
4721 * Set up the preferred ciphers. (NULL => warn below here)
4723 s
->n_preferred_ciphers
= 0;
4724 for (i
= 0; i
< CIPHER_MAX
; i
++) {
4725 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
4726 case CIPHER_BLOWFISH
:
4727 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
4730 if (ssh
->cfg
.ssh2_des_cbc
) {
4731 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
4735 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
4738 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
4741 /* Flag for later. Don't bother if it's the last in
4743 if (i
< CIPHER_MAX
- 1) {
4744 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
4751 * Set up preferred compression.
4753 if (ssh
->cfg
.compression
)
4754 s
->preferred_comp
= &ssh_zlib
;
4756 s
->preferred_comp
= &ssh_comp_none
;
4759 * Enable queueing of outgoing auth- or connection-layer
4760 * packets while we are in the middle of a key exchange.
4762 ssh
->queueing
= TRUE
;
4765 * Flag that KEX is in progress.
4767 ssh
->kex_in_progress
= TRUE
;
4770 * Construct and send our key exchange packet.
4772 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEXINIT
);
4773 for (i
= 0; i
< 16; i
++)
4774 ssh2_pkt_addbyte(s
->pktout
, (unsigned char) random_byte());
4775 /* List key exchange algorithms. */
4776 ssh2_pkt_addstring_start(s
->pktout
);
4777 commalist_started
= 0;
4778 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4779 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4780 if (!k
) continue; /* warning flag */
4781 if (commalist_started
)
4782 ssh2_pkt_addstring_str(s
->pktout
, ",");
4783 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_kex
[i
]->name
);
4784 commalist_started
= 1;
4786 /* List server host key algorithms. */
4787 ssh2_pkt_addstring_start(s
->pktout
);
4788 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4789 ssh2_pkt_addstring_str(s
->pktout
, hostkey_algs
[i
]->name
);
4790 if (i
< lenof(hostkey_algs
) - 1)
4791 ssh2_pkt_addstring_str(s
->pktout
, ",");
4793 /* List client->server encryption algorithms. */
4794 ssh2_pkt_addstring_start(s
->pktout
);
4795 commalist_started
= 0;
4796 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4797 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4798 if (!c
) continue; /* warning flag */
4799 for (j
= 0; j
< c
->nciphers
; j
++) {
4800 if (commalist_started
)
4801 ssh2_pkt_addstring_str(s
->pktout
, ",");
4802 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4803 commalist_started
= 1;
4806 /* List server->client encryption algorithms. */
4807 ssh2_pkt_addstring_start(s
->pktout
);
4808 commalist_started
= 0;
4809 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4810 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4811 if (!c
) continue; /* warning flag */
4812 for (j
= 0; j
< c
->nciphers
; j
++) {
4813 if (commalist_started
)
4814 ssh2_pkt_addstring_str(s
->pktout
, ",");
4815 ssh2_pkt_addstring_str(s
->pktout
, c
->list
[j
]->name
);
4816 commalist_started
= 1;
4819 /* List client->server MAC algorithms. */
4820 ssh2_pkt_addstring_start(s
->pktout
);
4821 for (i
= 0; i
< s
->nmacs
; i
++) {
4822 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4823 if (i
< s
->nmacs
- 1)
4824 ssh2_pkt_addstring_str(s
->pktout
, ",");
4826 /* List server->client MAC algorithms. */
4827 ssh2_pkt_addstring_start(s
->pktout
);
4828 for (i
= 0; i
< s
->nmacs
; i
++) {
4829 ssh2_pkt_addstring_str(s
->pktout
, s
->maclist
[i
]->name
);
4830 if (i
< s
->nmacs
- 1)
4831 ssh2_pkt_addstring_str(s
->pktout
, ",");
4833 /* List client->server compression algorithms. */
4834 ssh2_pkt_addstring_start(s
->pktout
);
4835 assert(lenof(compressions
) > 1);
4836 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4837 for (i
= 0; i
< lenof(compressions
); i
++) {
4838 const struct ssh_compress
*c
= compressions
[i
];
4839 if (c
!= s
->preferred_comp
) {
4840 ssh2_pkt_addstring_str(s
->pktout
, ",");
4841 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4844 /* List server->client compression algorithms. */
4845 ssh2_pkt_addstring_start(s
->pktout
);
4846 assert(lenof(compressions
) > 1);
4847 ssh2_pkt_addstring_str(s
->pktout
, s
->preferred_comp
->name
);
4848 for (i
= 0; i
< lenof(compressions
); i
++) {
4849 const struct ssh_compress
*c
= compressions
[i
];
4850 if (c
!= s
->preferred_comp
) {
4851 ssh2_pkt_addstring_str(s
->pktout
, ",");
4852 ssh2_pkt_addstring_str(s
->pktout
, c
->name
);
4855 /* List client->server languages. Empty list. */
4856 ssh2_pkt_addstring_start(s
->pktout
);
4857 /* List server->client languages. Empty list. */
4858 ssh2_pkt_addstring_start(s
->pktout
);
4859 /* First KEX packet does _not_ follow, because we're not that brave. */
4860 ssh2_pkt_addbool(s
->pktout
, FALSE
);
4862 ssh2_pkt_adduint32(s
->pktout
, 0);
4865 ssh
->exhash
= ssh
->exhashbase
;
4866 sha_string(&ssh
->exhash
, s
->pktout
->data
+ 5, s
->pktout
->length
- 5);
4868 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
4872 if (pktin
->length
> 5)
4873 sha_string(&ssh
->exhash
, pktin
->data
+ 5, pktin
->length
- 5);
4876 * Now examine the other side's KEXINIT to see what we're up
4883 if (pktin
->type
!= SSH2_MSG_KEXINIT
) {
4884 bombout(("expected key exchange packet from server"));
4888 ssh
->hostkey
= NULL
;
4889 s
->cscipher_tobe
= NULL
;
4890 s
->sccipher_tobe
= NULL
;
4891 s
->csmac_tobe
= NULL
;
4892 s
->scmac_tobe
= NULL
;
4893 s
->cscomp_tobe
= NULL
;
4894 s
->sccomp_tobe
= NULL
;
4895 pktin
->savedpos
+= 16; /* skip garbage cookie */
4896 ssh_pkt_getstring(pktin
, &str
, &len
); /* key exchange algorithms */
4898 for (i
= 0; i
< s
->n_preferred_kex
; i
++) {
4899 const struct ssh_kex
*k
= s
->preferred_kex
[i
];
4902 } else if (in_commasep_string(k
->name
, str
, len
)) {
4907 sk_set_frozen(ssh
->s
, 1);
4908 askalg(ssh
->frontend
, "key-exchange algorithm",
4910 sk_set_frozen(ssh
->s
, 0);
4916 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4917 str ? str
: "(null)"));
4920 ssh_pkt_getstring(pktin
, &str
, &len
); /* host key algorithms */
4921 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
4922 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
4923 ssh
->hostkey
= hostkey_algs
[i
];
4927 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server cipher */
4929 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4930 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4934 for (j
= 0; j
< c
->nciphers
; j
++) {
4935 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4936 s
->cscipher_tobe
= c
->list
[j
];
4941 if (s
->cscipher_tobe
) {
4943 sk_set_frozen(ssh
->s
, 1);
4944 askalg(ssh
->frontend
, "client-to-server cipher",
4945 s
->cscipher_tobe
->name
);
4946 sk_set_frozen(ssh
->s
, 0);
4951 if (!s
->cscipher_tobe
) {
4952 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
4953 str ? str
: "(null)"));
4957 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client cipher */
4959 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
4960 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
4964 for (j
= 0; j
< c
->nciphers
; j
++) {
4965 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
4966 s
->sccipher_tobe
= c
->list
[j
];
4971 if (s
->sccipher_tobe
) {
4973 sk_set_frozen(ssh
->s
, 1);
4974 askalg(ssh
->frontend
, "server-to-client cipher",
4975 s
->sccipher_tobe
->name
);
4976 sk_set_frozen(ssh
->s
, 0);
4981 if (!s
->sccipher_tobe
) {
4982 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
4983 str ? str
: "(null)"));
4987 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server mac */
4988 for (i
= 0; i
< s
->nmacs
; i
++) {
4989 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4990 s
->csmac_tobe
= s
->maclist
[i
];
4994 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client mac */
4995 for (i
= 0; i
< s
->nmacs
; i
++) {
4996 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
4997 s
->scmac_tobe
= s
->maclist
[i
];
5001 ssh_pkt_getstring(pktin
, &str
, &len
); /* client->server compression */
5002 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5003 const struct ssh_compress
*c
=
5004 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5005 if (in_commasep_string(c
->name
, str
, len
)) {
5010 ssh_pkt_getstring(pktin
, &str
, &len
); /* server->client compression */
5011 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
5012 const struct ssh_compress
*c
=
5013 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
5014 if (in_commasep_string(c
->name
, str
, len
)) {
5022 * Work out the number of bits of key we will need from the key
5023 * exchange. We start with the maximum key length of either
5029 csbits
= s
->cscipher_tobe
->keylen
;
5030 scbits
= s
->sccipher_tobe
->keylen
;
5031 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
5033 /* The keys only have 160-bit entropy, since they're based on
5034 * a SHA-1 hash. So cap the key size at 160 bits. */
5039 * If we're doing Diffie-Hellman group exchange, start by
5040 * requesting a group.
5042 if (!ssh
->kex
->pdata
) {
5043 logevent("Doing Diffie-Hellman group exchange");
5044 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
5046 * Work out how big a DH group we will need to allow that
5049 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
5050 s
->pktout
= ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
5051 ssh2_pkt_adduint32(s
->pktout
, s
->pbits
);
5052 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5055 if (pktin
->type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
5056 bombout(("expected key exchange group packet from server"));
5059 s
->p
= ssh2_pkt_getmp(pktin
);
5060 s
->g
= ssh2_pkt_getmp(pktin
);
5061 if (!s
->p
|| !s
->g
) {
5062 bombout(("unable to read mp-ints from incoming group packet"));
5065 ssh
->kex_ctx
= dh_setup_gex(s
->p
, s
->g
);
5066 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
5067 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
5069 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP
;
5070 ssh
->kex_ctx
= dh_setup_group(ssh
->kex
);
5071 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
5072 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
5073 logeventf(ssh
, "Using Diffie-Hellman with standard group \"%s\"",
5074 ssh
->kex
->groupname
);
5077 logevent("Doing Diffie-Hellman key exchange");
5079 * Now generate and send e for Diffie-Hellman.
5081 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
5082 s
->pktout
= ssh2_pkt_init(s
->kex_init_value
);
5083 ssh2_pkt_addmp(s
->pktout
, s
->e
);
5084 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5087 if (pktin
->type
!= s
->kex_reply_value
) {
5088 bombout(("expected key exchange reply packet from server"));
5091 ssh_pkt_getstring(pktin
, &s
->hostkeydata
, &s
->hostkeylen
);
5092 s
->f
= ssh2_pkt_getmp(pktin
);
5094 bombout(("unable to parse key exchange reply packet"));
5097 ssh_pkt_getstring(pktin
, &s
->sigdata
, &s
->siglen
);
5099 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
5101 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
5102 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5103 sha_uint32(&ssh
->exhash
, s
->pbits
);
5104 sha_mpint(&ssh
->exhash
, s
->p
);
5105 sha_mpint(&ssh
->exhash
, s
->g
);
5107 sha_mpint(&ssh
->exhash
, s
->e
);
5108 sha_mpint(&ssh
->exhash
, s
->f
);
5109 sha_mpint(&ssh
->exhash
, s
->K
);
5110 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
5112 dh_cleanup(ssh
->kex_ctx
);
5113 ssh
->kex_ctx
= NULL
;
5116 debug(("Exchange hash is:\n"));
5117 dmemdump(s
->exchange_hash
, 20);
5120 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
5122 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
5123 (char *)s
->exchange_hash
, 20)) {
5124 bombout(("Server's host key did not match the signature supplied"));
5129 * Authenticate remote host: verify host key. (We've already
5130 * checked the signature of the exchange hash.)
5132 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
5133 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
5134 sk_set_frozen(ssh
->s
, 1);
5135 verify_ssh_host_key(ssh
->frontend
,
5136 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
5137 s
->keystr
, s
->fingerprint
);
5138 sk_set_frozen(ssh
->s
, 0);
5139 if (!s
->got_session_id
) { /* don't bother logging this in rekeys */
5140 logevent("Host key fingerprint is:");
5141 logevent(s
->fingerprint
);
5143 sfree(s
->fingerprint
);
5145 ssh
->hostkey
->freekey(s
->hkey
);
5148 * The exchange hash from the very first key exchange is also
5149 * the session id, used in session key construction and
5152 if (!s
->got_session_id
) {
5153 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
5154 sizeof(s
->exchange_hash
));
5155 s
->got_session_id
= TRUE
;
5159 * Send SSH2_MSG_NEWKEYS.
5161 s
->pktout
= ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
5162 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5163 ssh
->outgoing_data_size
= 0; /* start counting from here */
5166 * We've sent client NEWKEYS, so create and initialise
5167 * client-to-server session keys.
5169 if (ssh
->cs_cipher_ctx
)
5170 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
5171 ssh
->cscipher
= s
->cscipher_tobe
;
5172 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
5174 if (ssh
->cs_mac_ctx
)
5175 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
5176 ssh
->csmac
= s
->csmac_tobe
;
5177 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
5179 if (ssh
->cs_comp_ctx
)
5180 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
5181 ssh
->cscomp
= s
->cscomp_tobe
;
5182 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
5185 * Set IVs on client-to-server keys. Here we use the exchange
5186 * hash from the _first_ key exchange.
5189 unsigned char keyspace
[40];
5190 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
5191 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
5192 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
5193 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
5194 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
5195 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
5198 logeventf(ssh
, "Initialised %.200s client->server encryption",
5199 ssh
->cscipher
->text_name
);
5200 logeventf(ssh
, "Initialised %.200s client->server MAC algorithm",
5201 ssh
->csmac
->text_name
);
5202 if (ssh
->cscomp
->text_name
)
5203 logeventf(ssh
, "Initialised %s compression",
5204 ssh
->cscomp
->text_name
);
5207 * Now our end of the key exchange is complete, we can send all
5208 * our queued higher-layer packets.
5210 ssh
->queueing
= FALSE
;
5211 ssh2_pkt_queuesend(ssh
);
5214 * Expect SSH2_MSG_NEWKEYS from server.
5217 if (pktin
->type
!= SSH2_MSG_NEWKEYS
) {
5218 bombout(("expected new-keys packet from server"));
5221 ssh
->incoming_data_size
= 0; /* start counting from here */
5224 * We've seen server NEWKEYS, so create and initialise
5225 * server-to-client session keys.
5227 if (ssh
->sc_cipher_ctx
)
5228 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
5229 ssh
->sccipher
= s
->sccipher_tobe
;
5230 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
5232 if (ssh
->sc_mac_ctx
)
5233 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
5234 ssh
->scmac
= s
->scmac_tobe
;
5235 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
5237 if (ssh
->sc_comp_ctx
)
5238 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
5239 ssh
->sccomp
= s
->sccomp_tobe
;
5240 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
5243 * Set IVs on server-to-client keys. Here we use the exchange
5244 * hash from the _first_ key exchange.
5247 unsigned char keyspace
[40];
5248 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
5249 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
5250 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
5251 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
5252 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
5253 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
5255 logeventf(ssh
, "Initialised %.200s server->client encryption",
5256 ssh
->sccipher
->text_name
);
5257 logeventf(ssh
, "Initialised %.200s server->client MAC algorithm",
5258 ssh
->scmac
->text_name
);
5259 if (ssh
->sccomp
->text_name
)
5260 logeventf(ssh
, "Initialised %s decompression",
5261 ssh
->sccomp
->text_name
);
5264 * Free key exchange data.
5268 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
5274 * Key exchange is over. Loop straight back round if we have a
5275 * deferred rekey reason.
5277 if (ssh
->deferred_rekey_reason
) {
5278 logevent(ssh
->deferred_rekey_reason
);
5280 ssh
->deferred_rekey_reason
= NULL
;
5281 goto begin_key_exchange
;
5285 * Otherwise, schedule a timer for our next rekey.
5287 ssh
->kex_in_progress
= FALSE
;
5288 ssh
->last_rekey
= GETTICKCOUNT();
5289 if (ssh
->cfg
.ssh_rekey_time
!= 0)
5290 ssh
->next_rekey
= schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5294 * If this is the first key exchange phase, we must pass the
5295 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5296 * wants to see it but because it will need time to initialise
5297 * itself before it sees an actual packet. In subsequent key
5298 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5299 * it would only confuse the layer above.
5301 if (s
->activated_authconn
) {
5304 s
->activated_authconn
= TRUE
;
5307 * Now we're encrypting. Begin returning 1 to the protocol main
5308 * function so that other things can run on top of the
5309 * transport. If we ever see a KEXINIT, we must go back to the
5312 * We _also_ go back to the start if we see pktin==NULL and
5313 * inlen==-1, because this is a special signal meaning
5314 * `initiate client-driven rekey', and `in' contains a message
5315 * giving the reason for the rekey.
5317 while (!((pktin
&& pktin
->type
== SSH2_MSG_KEXINIT
) ||
5318 (!pktin
&& inlen
== -1))) {
5323 logevent("Server initiated key re-exchange");
5326 * Special case: if the server bug is set that doesn't
5327 * allow rekeying, we give a different log message and
5328 * continue waiting. (If such a server _initiates_ a rekey,
5329 * we process it anyway!)
5331 if ((ssh
->remote_bugs
& BUG_SSH2_REKEY
)) {
5332 logeventf(ssh
, "Server bug prevents key re-exchange (%s)",
5334 /* Reset the counters, so that at least this message doesn't
5335 * hit the event log _too_ often. */
5336 ssh
->outgoing_data_size
= 0;
5337 ssh
->incoming_data_size
= 0;
5338 if (ssh
->cfg
.ssh_rekey_time
!= 0) {
5340 schedule_timer(ssh
->cfg
.ssh_rekey_time
*60*TICKSPERSEC
,
5343 goto wait_for_rekey
; /* this is utterly horrid */
5345 logeventf(ssh
, "Initiating key re-exchange (%s)", (char *)in
);
5346 logevent((char *)in
);
5349 goto begin_key_exchange
;
5355 * Add data to an SSH2 channel output buffer.
5357 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
5360 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
5364 * Attempt to send data on an SSH2 channel.
5366 static int ssh2_try_send(struct ssh_channel
*c
)
5369 struct Packet
*pktout
;
5371 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
5374 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
5375 if ((unsigned)len
> c
->v
.v2
.remwindow
)
5376 len
= c
->v
.v2
.remwindow
;
5377 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
5378 len
= c
->v
.v2
.remmaxpkt
;
5379 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
5380 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5381 dont_log_data(ssh
, pktout
, PKTLOG_OMIT
);
5382 ssh2_pkt_addstring_start(pktout
);
5383 ssh2_pkt_addstring_data(pktout
, data
, len
);
5384 end_log_omission(ssh
, pktout
);
5385 ssh2_pkt_send(ssh
, pktout
);
5386 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
5387 c
->v
.v2
.remwindow
-= len
;
5391 * After having sent as much data as we can, return the amount
5394 return bufchain_size(&c
->v
.v2
.outbuffer
);
5398 * Potentially enlarge the window on an SSH2 channel.
5400 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
5405 * Never send WINDOW_ADJUST for a channel that the remote side
5406 * already thinks it's closed; there's no point, since it won't
5407 * be sending any more data anyway.
5412 if (newwin
> c
->v
.v2
.locwindow
) {
5413 struct Packet
*pktout
;
5415 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5416 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5417 ssh2_pkt_adduint32(pktout
, newwin
- c
->v
.v2
.locwindow
);
5418 ssh2_pkt_send(ssh
, pktout
);
5419 c
->v
.v2
.locwindow
= newwin
;
5423 static void ssh2_msg_channel_window_adjust(Ssh ssh
, struct Packet
*pktin
)
5425 unsigned i
= ssh_pkt_getuint32(pktin
);
5426 struct ssh_channel
*c
;
5427 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5428 if (c
&& !c
->closes
)
5429 c
->v
.v2
.remwindow
+= ssh_pkt_getuint32(pktin
);
5432 static void ssh2_msg_channel_data(Ssh ssh
, struct Packet
*pktin
)
5435 unsigned int length
;
5436 unsigned i
= ssh_pkt_getuint32(pktin
);
5437 struct ssh_channel
*c
;
5438 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5440 return; /* nonexistent channel */
5441 if (pktin
->type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5442 ssh_pkt_getuint32(pktin
) != SSH2_EXTENDED_DATA_STDERR
)
5443 return; /* extended but not stderr */
5444 ssh_pkt_getstring(pktin
, &data
, &length
);
5447 c
->v
.v2
.locwindow
-= length
;
5449 case CHAN_MAINSESSION
:
5451 from_backend(ssh
->frontend
, pktin
->type
==
5452 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5456 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5459 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5462 while (length
> 0) {
5463 if (c
->u
.a
.lensofar
< 4) {
5464 unsigned int l
= min(4 - c
->u
.a
.lensofar
, length
);
5465 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5469 c
->u
.a
.lensofar
+= l
;
5471 if (c
->u
.a
.lensofar
== 4) {
5473 4 + GET_32BIT(c
->u
.a
.msglen
);
5474 c
->u
.a
.message
= snewn(c
->u
.a
.totallen
,
5476 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5478 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5480 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5482 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5486 c
->u
.a
.lensofar
+= l
;
5488 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5491 if (agent_query(c
->u
.a
.message
,
5494 ssh_agentf_callback
, c
))
5495 ssh_agentf_callback(c
, reply
, replylen
);
5496 sfree(c
->u
.a
.message
);
5497 c
->u
.a
.lensofar
= 0;
5504 * If we are not buffering too much data,
5505 * enlarge the window again at the remote side.
5507 if (bufsize
< OUR_V2_WINSIZE
)
5508 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5512 static void ssh2_msg_channel_eof(Ssh ssh
, struct Packet
*pktin
)
5514 unsigned i
= ssh_pkt_getuint32(pktin
);
5515 struct ssh_channel
*c
;
5517 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5519 return; /* nonexistent channel */
5521 if (c
->type
== CHAN_X11
) {
5523 * Remote EOF on an X11 channel means we should
5524 * wrap up and close the channel ourselves.
5526 x11_close(c
->u
.x11
.s
);
5528 } else if (c
->type
== CHAN_AGENT
) {
5530 } else if (c
->type
== CHAN_SOCKDATA
) {
5531 pfd_close(c
->u
.pfd
.s
);
5536 static void ssh2_msg_channel_close(Ssh ssh
, struct Packet
*pktin
)
5538 unsigned i
= ssh_pkt_getuint32(pktin
);
5539 struct ssh_channel
*c
;
5540 struct Packet
*pktout
;
5542 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5543 if (!c
|| ((int)c
->remoteid
) == -1) {
5544 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5545 c ?
"half-open" : "nonexistent", i
));
5548 /* Do pre-close processing on the channel. */
5550 case CHAN_MAINSESSION
:
5551 ssh
->mainchan
= NULL
;
5552 update_specials_menu(ssh
->frontend
);
5555 if (c
->u
.x11
.s
!= NULL
)
5556 x11_close(c
->u
.x11
.s
);
5563 if (c
->u
.pfd
.s
!= NULL
)
5564 pfd_close(c
->u
.pfd
.s
);
5568 if (c
->closes
== 0) {
5569 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5570 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5571 ssh2_pkt_send(ssh
, pktout
);
5573 del234(ssh
->channels
, c
);
5574 bufchain_clear(&c
->v
.v2
.outbuffer
);
5578 * See if that was the last channel left open.
5579 * (This is only our termination condition if we're
5580 * not running in -N mode.)
5582 if (!ssh
->cfg
.ssh_no_shell
&& count234(ssh
->channels
) == 0) {
5583 logevent("All channels closed. Disconnecting");
5586 * We used to send SSH_MSG_DISCONNECT here,
5587 * because I'd believed that _every_ conforming
5588 * SSH2 connection had to end with a disconnect
5589 * being sent by at least one side; apparently
5590 * I was wrong and it's perfectly OK to
5591 * unceremoniously slam the connection shut
5592 * when you're done, and indeed OpenSSH feels
5593 * this is more polite than sending a
5594 * DISCONNECT. So now we don't.
5596 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5597 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5598 ssh2_pkt_addstring(s
->pktout
, "All open channels closed");
5599 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
5600 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
5602 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5606 static void ssh2_msg_channel_open_confirmation(Ssh ssh
, struct Packet
*pktin
)
5608 unsigned i
= ssh_pkt_getuint32(pktin
);
5609 struct ssh_channel
*c
;
5610 struct Packet
*pktout
;
5612 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5614 return; /* nonexistent channel */
5615 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5616 return; /* dunno why they're confirming this */
5617 c
->remoteid
= ssh_pkt_getuint32(pktin
);
5618 c
->type
= CHAN_SOCKDATA
;
5619 c
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
5620 c
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
5622 pfd_confirm(c
->u
.pfd
.s
);
5625 * We have a pending close on this channel,
5626 * which we decided on before the server acked
5627 * the channel open. So now we know the
5628 * remoteid, we can close it again.
5630 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
5631 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5632 ssh2_pkt_send(ssh
, pktout
);
5636 static void ssh2_msg_channel_open_failure(Ssh ssh
, struct Packet
*pktin
)
5638 static const char *const reasons
[] = {
5639 "<unknown reason code>",
5640 "Administratively prohibited",
5642 "Unknown channel type",
5643 "Resource shortage",
5645 unsigned i
= ssh_pkt_getuint32(pktin
);
5646 unsigned reason_code
;
5647 char *reason_string
;
5650 struct ssh_channel
*c
;
5651 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5653 return; /* nonexistent channel */
5654 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5655 return; /* dunno why they're failing this */
5657 reason_code
= ssh_pkt_getuint32(pktin
);
5658 if (reason_code
>= lenof(reasons
))
5659 reason_code
= 0; /* ensure reasons[reason_code] in range */
5660 ssh_pkt_getstring(pktin
, &reason_string
, &reason_length
);
5661 message
= dupprintf("Forwarded connection refused by"
5662 " server: %s [%.*s]", reasons
[reason_code
],
5663 reason_length
, reason_string
);
5667 pfd_close(c
->u
.pfd
.s
);
5669 del234(ssh
->channels
, c
);
5673 static void ssh2_msg_channel_request(Ssh ssh
, struct Packet
*pktin
)
5677 int typelen
, want_reply
;
5678 int reply
= SSH2_MSG_CHANNEL_FAILURE
; /* default */
5679 struct ssh_channel
*c
;
5680 struct Packet
*pktout
;
5682 localid
= ssh_pkt_getuint32(pktin
);
5683 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5684 want_reply
= ssh2_pkt_getbool(pktin
);
5687 * First, check that the channel exists. Otherwise,
5688 * we can instantly disconnect with a rude message.
5690 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5693 sprintf(buf
, "Received channel request for nonexistent"
5694 " channel %d", localid
);
5696 pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
5697 ssh2_pkt_adduint32(pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
5698 ssh2_pkt_addstring(pktout
, buf
);
5699 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5700 ssh2_pkt_send_noqueue(ssh
, pktout
);
5701 connection_fatal(ssh
->frontend
, "%s", buf
);
5702 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
5707 * Having got the channel number, we now look at
5708 * the request type string to see if it's something
5711 if (c
== ssh
->mainchan
) {
5713 * We recognise "exit-status" and "exit-signal" on
5714 * the primary channel.
5716 if (typelen
== 11 &&
5717 !memcmp(type
, "exit-status", 11)) {
5719 ssh
->exitcode
= ssh_pkt_getuint32(pktin
);
5720 logeventf(ssh
, "Server sent command exit status %d",
5722 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5724 } else if (typelen
== 11 &&
5725 !memcmp(type
, "exit-signal", 11)) {
5727 int is_plausible
= TRUE
, is_int
= FALSE
;
5728 char *fmt_sig
= "", *fmt_msg
= "";
5730 int msglen
= 0, core
= FALSE
;
5731 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5732 * provide an `int' for the signal, despite its
5733 * having been a `string' in the drafts since at
5734 * least 2001. (Fixed in session.c 1.147.) Try to
5735 * infer which we can safely parse it as. */
5737 unsigned char *p
= pktin
->body
+
5739 long len
= pktin
->length
- pktin
->savedpos
;
5740 unsigned long num
= GET_32BIT(p
); /* what is it? */
5741 /* If it's 0, it hardly matters; assume string */
5745 int maybe_int
= FALSE
, maybe_str
= FALSE
;
5746 #define CHECK_HYPOTHESIS(offset, result) \
5749 if (q >= 0 && q+4 <= len) { \
5750 q = q + 4 + GET_32BIT(p+q); \
5751 if (q >= 0 && q+4 <= len && \
5752 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5756 CHECK_HYPOTHESIS(4+1, maybe_int
);
5757 CHECK_HYPOTHESIS(4+num
+1, maybe_str
);
5758 #undef CHECK_HYPOTHESIS
5759 if (maybe_int
&& !maybe_str
)
5761 else if (!maybe_int
&& maybe_str
)
5764 /* Crikey. Either or neither. Panic. */
5765 is_plausible
= FALSE
;
5770 /* Old non-standard OpenSSH. */
5771 int signum
= ssh_pkt_getuint32(pktin
);
5772 fmt_sig
= dupprintf(" %d", signum
);
5774 /* As per the drafts. */
5777 ssh_pkt_getstring(pktin
, &sig
, &siglen
);
5778 /* Signal name isn't supposed to be blank, but
5779 * let's cope gracefully if it is. */
5781 fmt_sig
= dupprintf(" \"%.*s\"",
5785 core
= ssh2_pkt_getbool(pktin
);
5786 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
5788 fmt_msg
= dupprintf(" (\"%.*s\")", msglen
, msg
);
5790 /* ignore lang tag */
5791 } /* else don't attempt to parse */
5792 logeventf(ssh
, "Server exited on signal%s%s%s",
5793 fmt_sig
, core ?
" (core dumped)" : "",
5795 if (*fmt_sig
) sfree(fmt_sig
);
5796 if (*fmt_msg
) sfree(fmt_msg
);
5797 reply
= SSH2_MSG_CHANNEL_SUCCESS
;
5802 * This is a channel request we don't know
5803 * about, so we now either ignore the request
5804 * or respond with CHANNEL_FAILURE, depending
5807 reply
= SSH2_MSG_CHANNEL_FAILURE
;
5810 pktout
= ssh2_pkt_init(reply
);
5811 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5812 ssh2_pkt_send(ssh
, pktout
);
5816 static void ssh2_msg_global_request(Ssh ssh
, struct Packet
*pktin
)
5819 int typelen
, want_reply
;
5820 struct Packet
*pktout
;
5822 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5823 want_reply
= ssh2_pkt_getbool(pktin
);
5826 * We currently don't support any global requests
5827 * at all, so we either ignore the request or
5828 * respond with REQUEST_FAILURE, depending on
5832 pktout
= ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE
);
5833 ssh2_pkt_send(ssh
, pktout
);
5837 static void ssh2_msg_channel_open(Ssh ssh
, struct Packet
*pktin
)
5845 struct ssh_channel
*c
;
5846 unsigned remid
, winsize
, pktsize
;
5847 struct Packet
*pktout
;
5849 ssh_pkt_getstring(pktin
, &type
, &typelen
);
5850 c
= snew(struct ssh_channel
);
5853 remid
= ssh_pkt_getuint32(pktin
);
5854 winsize
= ssh_pkt_getuint32(pktin
);
5855 pktsize
= ssh_pkt_getuint32(pktin
);
5857 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5860 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5861 addrstr
= snewn(peeraddrlen
+1, char);
5862 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5863 addrstr
[peeraddrlen
] = '\0';
5864 peerport
= ssh_pkt_getuint32(pktin
);
5866 logeventf(ssh
, "Received X11 connect request from %s:%d",
5869 if (!ssh
->X11_fwd_enabled
)
5870 error
= "X11 forwarding is not enabled";
5871 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5872 ssh
->x11auth
, addrstr
, peerport
,
5873 &ssh
->cfg
) != NULL
) {
5874 error
= "Unable to open an X11 connection";
5876 logevent("Opening X11 forward connection succeeded");
5881 } else if (typelen
== 15 &&
5882 !memcmp(type
, "forwarded-tcpip", 15)) {
5883 struct ssh_rportfwd pf
, *realpf
;
5886 ssh_pkt_getstring(pktin
, &dummy
, &dummylen
);/* skip address */
5887 pf
.sport
= ssh_pkt_getuint32(pktin
);
5888 ssh_pkt_getstring(pktin
, &peeraddr
, &peeraddrlen
);
5889 peerport
= ssh_pkt_getuint32(pktin
);
5890 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5891 logeventf(ssh
, "Received remote port %d open request "
5892 "from %s:%d", pf
.sport
, peeraddr
, peerport
);
5893 if (realpf
== NULL
) {
5894 error
= "Remote port is not recognised";
5896 const char *e
= pfd_newconnect(&c
->u
.pfd
.s
,
5900 realpf
->pfrec
->addressfamily
);
5901 logeventf(ssh
, "Attempting to forward remote port to "
5902 "%s:%d", realpf
->dhost
, realpf
->dport
);
5904 logeventf(ssh
, "Port open failed: %s", e
);
5905 error
= "Port open failed";
5907 logevent("Forwarded port opened successfully");
5908 c
->type
= CHAN_SOCKDATA
;
5911 } else if (typelen
== 22 &&
5912 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5913 if (!ssh
->agentfwd_enabled
)
5914 error
= "Agent forwarding is not enabled";
5916 c
->type
= CHAN_AGENT
; /* identify channel type */
5917 c
->u
.a
.lensofar
= 0;
5920 error
= "Unsupported channel type requested";
5923 c
->remoteid
= remid
;
5925 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5926 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5927 ssh2_pkt_adduint32(pktout
, SSH2_OPEN_CONNECT_FAILED
);
5928 ssh2_pkt_addstring(pktout
, error
);
5929 ssh2_pkt_addstring(pktout
, "en"); /* language tag */
5930 ssh2_pkt_send(ssh
, pktout
);
5931 logeventf(ssh
, "Rejected channel open: %s", error
);
5934 c
->localid
= alloc_channel_id(ssh
);
5936 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5937 c
->v
.v2
.remwindow
= winsize
;
5938 c
->v
.v2
.remmaxpkt
= pktsize
;
5939 bufchain_init(&c
->v
.v2
.outbuffer
);
5940 add234(ssh
->channels
, c
);
5941 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5942 ssh2_pkt_adduint32(pktout
, c
->remoteid
);
5943 ssh2_pkt_adduint32(pktout
, c
->localid
);
5944 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);
5945 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
5946 ssh2_pkt_send(ssh
, pktout
);
5951 * Handle the SSH2 userauth and connection layers.
5953 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
,
5954 struct Packet
*pktin
)
5956 struct do_ssh2_authconn_state
{
5958 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
5960 AUTH_KEYBOARD_INTERACTIVE
5964 AUTH_TYPE_PUBLICKEY
,
5965 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
5966 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
5968 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
5969 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5971 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
5972 int tried_pubkey_config
, tried_agent
;
5973 int kbd_inter_running
, kbd_inter_refused
;
5975 int num_prompts
, curr_prompt
, echo
;
5980 void *publickey_blob
;
5981 int publickey_bloblen
;
5982 unsigned char request
[5], *response
, *p
;
5986 char *pkblob
, *alg
, *commentp
;
5987 int pklen
, alglen
, commentlen
;
5988 int siglen
, retlen
, len
;
5989 char *q
, *agentreq
, *ret
;
5991 int num_env
, env_left
, env_ok
;
5992 struct Packet
*pktout
;
5994 crState(do_ssh2_authconn_state
);
5996 crBegin(ssh
->do_ssh2_authconn_crstate
);
5999 * Request userauth protocol, and await a response to it.
6001 s
->pktout
= ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
6002 ssh2_pkt_addstring(s
->pktout
, "ssh-userauth");
6003 ssh2_pkt_send(ssh
, s
->pktout
);
6004 crWaitUntilV(pktin
);
6005 if (pktin
->type
!= SSH2_MSG_SERVICE_ACCEPT
) {
6006 bombout(("Server refused user authentication protocol"));
6011 * We repeat this whole loop, including the username prompt,
6012 * until we manage a successful authentication. If the user
6013 * types the wrong _password_, they can be sent back to the
6014 * beginning to try another username, if this is configured on.
6015 * (If they specify a username in the config, they are never
6016 * asked, even if they do give a wrong password.)
6018 * I think this best serves the needs of
6020 * - the people who have no configuration, no keys, and just
6021 * want to try repeated (username,password) pairs until they
6022 * type both correctly
6024 * - people who have keys and configuration but occasionally
6025 * need to fall back to passwords
6027 * - people with a key held in Pageant, who might not have
6028 * logged in to a particular machine before; so they want to
6029 * type a username, and then _either_ their key will be
6030 * accepted, _or_ they will type a password. If they mistype
6031 * the username they will want to be able to get back and
6034 s
->username
[0] = '\0';
6035 s
->got_username
= FALSE
;
6040 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
6042 * We got a username last time round this loop, and
6043 * with change_username turned off we don't try to get
6046 } else if (!*ssh
->cfg
.username
) {
6047 if (ssh_get_line
&& !ssh_getline_pw_only
) {
6048 if (!ssh_get_line("login as: ",
6049 s
->username
, sizeof(s
->username
), FALSE
)) {
6051 * get_line failed to get a username.
6054 logevent("No username provided. Abandoning session.");
6055 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6059 int ret
; /* need not be saved across crReturn */
6060 c_write_str(ssh
, "login as: ");
6062 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
6064 crWaitUntilV(!pktin
);
6065 ret
= process_userpass_input(ssh
, in
, inlen
);
6069 c_write_str(ssh
, "\r\n");
6071 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
6074 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
6075 s
->username
[sizeof(s
->username
)-1] = '\0';
6076 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
6077 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
6078 c_write_str(ssh
, stuff
);
6082 s
->got_username
= TRUE
;
6085 * Send an authentication request using method "none": (a)
6086 * just in case it succeeds, and (b) so that we know what
6087 * authentication methods we can usefully try next.
6089 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6091 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6092 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6093 ssh2_pkt_addstring(s
->pktout
, "ssh-connection");/* service requested */
6094 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6095 ssh2_pkt_send(ssh
, s
->pktout
);
6096 s
->type
= AUTH_TYPE_NONE
;
6098 s
->we_are_in
= FALSE
;
6100 s
->tried_pubkey_config
= FALSE
;
6101 s
->tried_agent
= FALSE
;
6102 s
->kbd_inter_running
= FALSE
;
6103 s
->kbd_inter_refused
= FALSE
;
6104 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
6105 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
6107 logeventf(ssh
, "Reading private key file \"%.150s\"",
6108 filename_to_str(&ssh
->cfg
.keyfile
));
6109 keytype
= key_type(&ssh
->cfg
.keyfile
);
6110 if (keytype
== SSH_KEYTYPE_SSH2
) {
6112 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
6113 &s
->publickey_bloblen
, NULL
);
6116 logeventf(ssh
, "Unable to use this key file (%s)",
6117 key_type_to_str(keytype
));
6118 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
6120 filename_to_str(&ssh
->cfg
.keyfile
),
6121 key_type_to_str(keytype
));
6122 c_write_str(ssh
, msgbuf
);
6124 s
->publickey_blob
= NULL
;
6127 s
->publickey_blob
= NULL
;
6131 * Wait for the result of the last authentication request.
6134 crWaitUntilV(pktin
);
6135 while (pktin
->type
== SSH2_MSG_USERAUTH_BANNER
) {
6139 * Don't show the banner if we're operating in
6140 * non-verbose non-interactive mode. (It's probably
6141 * a script, which means nobody will read the
6142 * banner _anyway_, and moreover the printing of
6143 * the banner will screw up processing on the
6144 * output of (say) plink.)
6146 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
6147 ssh_pkt_getstring(pktin
, &banner
, &size
);
6149 c_write_untrusted(ssh
, banner
, size
);
6151 crWaitUntilV(pktin
);
6153 if (pktin
->type
== SSH2_MSG_USERAUTH_SUCCESS
) {
6154 logevent("Access granted");
6155 s
->we_are_in
= TRUE
;
6159 if (s
->kbd_inter_running
&&
6160 pktin
->type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6162 * This is either a further set-of-prompts packet
6163 * in keyboard-interactive authentication, or it's
6164 * the same one and we came back here with `gotit'
6165 * set. In the former case, we must reset the
6166 * curr_prompt variable.
6170 } else if (pktin
->type
== SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
) {
6171 /* FIXME: perhaps we should support this? */
6172 bombout(("PASSWD_CHANGEREQ not yet supported"));
6174 } else if (pktin
->type
!= SSH2_MSG_USERAUTH_FAILURE
) {
6175 bombout(("Strange packet received during authentication: type %d",
6183 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6184 * we can look at the string in it and know what we can
6185 * helpfully try next.
6187 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
) {
6190 ssh_pkt_getstring(pktin
, &methods
, &methlen
);
6191 s
->kbd_inter_running
= FALSE
;
6192 if (!ssh2_pkt_getbool(pktin
)) {
6194 * We have received an unequivocal Access
6195 * Denied. This can translate to a variety of
6198 * - if we'd just tried "none" authentication,
6199 * it's not worth printing anything at all
6201 * - if we'd just tried a public key _offer_,
6202 * the message should be "Server refused our
6203 * key" (or no message at all if the key
6204 * came from Pageant)
6206 * - if we'd just tried anything else, the
6207 * message really should be "Access denied".
6209 * Additionally, if we'd just tried password
6210 * authentication, we should break out of this
6211 * whole loop so as to go back to the username
6212 * prompt (iff we're configured to allow
6213 * username change attempts).
6215 if (s
->type
== AUTH_TYPE_NONE
) {
6217 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
6218 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
6219 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
6220 c_write_str(ssh
, "Server refused our key\r\n");
6221 logevent("Server refused public key");
6222 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
6223 /* server declined keyboard-interactive; ignore */
6225 c_write_str(ssh
, "Access denied\r\n");
6226 logevent("Access denied");
6227 if (s
->type
== AUTH_TYPE_PASSWORD
&&
6228 ssh
->cfg
.change_username
) {
6229 /* XXX perhaps we should allow
6230 * keyboard-interactive to do this too? */
6231 s
->we_are_in
= FALSE
;
6236 c_write_str(ssh
, "Further authentication required\r\n");
6237 logevent("Further authentication required");
6241 in_commasep_string("publickey", methods
, methlen
);
6243 in_commasep_string("password", methods
, methlen
);
6244 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
6245 in_commasep_string("keyboard-interactive", methods
, methlen
);
6249 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6253 * Most password/passphrase prompts will be
6254 * non-echoing, so we set this to 0 by default.
6255 * Exception is that some keyboard-interactive prompts
6256 * can be echoing, in which case we'll set this to 1.
6260 if (!s
->method
&& s
->can_pubkey
&&
6261 agent_exists() && !s
->tried_agent
) {
6263 * Attempt public-key authentication using Pageant.
6268 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6269 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6271 s
->tried_agent
= TRUE
;
6273 logevent("Pageant is running. Requesting keys.");
6275 /* Request the keys held by the agent. */
6276 PUT_32BIT(s
->request
, 1);
6277 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
6278 if (!agent_query(s
->request
, 5, &r
, &s
->responselen
,
6279 ssh_agent_callback
, ssh
)) {
6283 bombout(("Unexpected data from server while"
6284 " waiting for agent response"));
6287 } while (pktin
|| inlen
> 0);
6288 r
= ssh
->agent_response
;
6289 s
->responselen
= ssh
->agent_response_len
;
6291 s
->response
= (unsigned char *) r
;
6292 if (s
->response
&& s
->responselen
>= 5 &&
6293 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
6294 s
->p
= s
->response
+ 5;
6295 s
->nkeys
= GET_32BIT(s
->p
);
6299 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
6302 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
6307 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
6310 s
->pklen
= GET_32BIT(s
->p
);
6312 if (s
->publickey_blob
&&
6313 s
->pklen
== s
->publickey_bloblen
&&
6314 !memcmp(s
->p
, s
->publickey_blob
,
6315 s
->publickey_bloblen
)) {
6316 logevent("This key matches configured key file");
6317 s
->tried_pubkey_config
= 1;
6319 s
->pkblob
= (char *)s
->p
;
6321 s
->alglen
= GET_32BIT(s
->pkblob
);
6322 s
->alg
= s
->pkblob
+ 4;
6323 s
->commentlen
= GET_32BIT(s
->p
);
6325 s
->commentp
= (char *)s
->p
;
6326 s
->p
+= s
->commentlen
;
6327 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6328 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6329 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6330 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6331 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6332 ssh2_pkt_addstring_start(s
->pktout
);
6333 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6334 ssh2_pkt_addstring_start(s
->pktout
);
6335 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6336 ssh2_pkt_send(ssh
, s
->pktout
);
6338 crWaitUntilV(pktin
);
6339 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6340 logevent("Key refused");
6344 if (flags
& FLAG_VERBOSE
) {
6345 c_write_str(ssh
, "Authenticating with "
6347 c_write(ssh
, s
->commentp
, s
->commentlen
);
6348 c_write_str(ssh
, "\" from agent\r\n");
6352 * Server is willing to accept the key.
6353 * Construct a SIGN_REQUEST.
6355 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6356 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6357 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6358 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6359 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6360 ssh2_pkt_addstring_start(s
->pktout
);
6361 ssh2_pkt_addstring_data(s
->pktout
, s
->alg
, s
->alglen
);
6362 ssh2_pkt_addstring_start(s
->pktout
);
6363 ssh2_pkt_addstring_data(s
->pktout
, s
->pkblob
, s
->pklen
);
6365 s
->siglen
= s
->pktout
->length
- 5 + 4 + 20;
6366 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6368 s
->len
= 1; /* message type */
6369 s
->len
+= 4 + s
->pklen
; /* key blob */
6370 s
->len
+= 4 + s
->siglen
; /* data to sign */
6371 s
->len
+= 4; /* flags */
6372 s
->agentreq
= snewn(4 + s
->len
, char);
6373 PUT_32BIT(s
->agentreq
, s
->len
);
6374 s
->q
= s
->agentreq
+ 4;
6375 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
6376 PUT_32BIT(s
->q
, s
->pklen
);
6378 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
6380 PUT_32BIT(s
->q
, s
->siglen
);
6382 /* Now the data to be signed... */
6383 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6384 PUT_32BIT(s
->q
, 20);
6387 memcpy(s
->q
, ssh
->v2_session_id
, 20);
6389 memcpy(s
->q
, s
->pktout
->data
+ 5,
6390 s
->pktout
->length
- 5);
6391 s
->q
+= s
->pktout
->length
- 5;
6392 /* And finally the (zero) flags word. */
6394 if (!agent_query(s
->agentreq
, s
->len
+ 4,
6396 ssh_agent_callback
, ssh
)) {
6400 bombout(("Unexpected data from server"
6401 " while waiting for agent"
6405 } while (pktin
|| inlen
> 0);
6406 vret
= ssh
->agent_response
;
6407 s
->retlen
= ssh
->agent_response_len
;
6412 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
6413 logevent("Sending Pageant's response");
6414 ssh2_add_sigblob(ssh
, s
->pktout
,
6415 s
->pkblob
, s
->pklen
,
6417 GET_32BIT(s
->ret
+ 5));
6418 ssh2_pkt_send(ssh
, s
->pktout
);
6423 ("Pageant failed to answer challenge");
6434 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
6435 && !s
->tried_pubkey_config
) {
6436 unsigned char *pub_blob
;
6437 char *algorithm
, *comment
;
6440 s
->tried_pubkey_config
= TRUE
;
6442 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6443 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
6446 * Try the public key supplied in the configuration.
6448 * First, offer the public blob to see if the server is
6449 * willing to accept it.
6452 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
6457 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6458 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6459 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6460 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6461 ssh2_pkt_addbool(s
->pktout
, FALSE
); /* no signature included */
6462 ssh2_pkt_addstring(s
->pktout
, algorithm
);
6463 ssh2_pkt_addstring_start(s
->pktout
);
6464 ssh2_pkt_addstring_data(s
->pktout
, (char *)pub_blob
,
6466 ssh2_pkt_send(ssh
, s
->pktout
);
6467 logevent("Offered public key");
6469 crWaitUntilV(pktin
);
6470 if (pktin
->type
!= SSH2_MSG_USERAUTH_PK_OK
) {
6472 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
6473 continue; /* key refused; give up on it */
6476 logevent("Offer of public key accepted");
6478 * Actually attempt a serious authentication using
6481 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
6482 sprintf(s
->pwprompt
,
6483 "Passphrase for key \"%.100s\": ",
6489 if (flags
& FLAG_VERBOSE
) {
6490 c_write_str(ssh
, "Authenticating with public key \"");
6491 c_write_str(ssh
, comment
);
6492 c_write_str(ssh
, "\"\r\n");
6494 s
->method
= AUTH_PUBLICKEY_FILE
;
6498 if (!s
->method
&& s
->can_keyb_inter
&& !s
->kbd_inter_refused
&&
6499 !s
->kbd_inter_running
) {
6500 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6501 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6503 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6504 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6506 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6507 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6508 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6509 ssh2_pkt_addstring(s
->pktout
, "keyboard-interactive"); /* method */
6510 ssh2_pkt_addstring(s
->pktout
, ""); /* lang */
6511 ssh2_pkt_addstring(s
->pktout
, "");
6512 ssh2_pkt_send(ssh
, s
->pktout
);
6514 crWaitUntilV(pktin
);
6515 if (pktin
->type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
6516 if (pktin
->type
== SSH2_MSG_USERAUTH_FAILURE
)
6518 logevent("Keyboard-interactive authentication refused");
6519 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
6520 s
->kbd_inter_refused
= TRUE
; /* don't try it again */
6524 s
->kbd_inter_running
= TRUE
;
6528 if (s
->kbd_inter_running
) {
6529 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
6530 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6532 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6533 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
6535 if (s
->curr_prompt
== 0) {
6537 * We've got a fresh USERAUTH_INFO_REQUEST.
6538 * Display header data, and start going through
6541 char *name
, *inst
, *lang
;
6542 int name_len
, inst_len
, lang_len
;
6544 ssh_pkt_getstring(pktin
, &name
, &name_len
);
6545 ssh_pkt_getstring(pktin
, &inst
, &inst_len
);
6546 ssh_pkt_getstring(pktin
, &lang
, &lang_len
);
6548 c_write_untrusted(ssh
, name
, name_len
);
6549 c_write_str(ssh
, "\r\n");
6552 c_write_untrusted(ssh
, inst
, inst_len
);
6553 c_write_str(ssh
, "\r\n");
6555 s
->num_prompts
= ssh_pkt_getuint32(pktin
);
6559 * If there are prompts remaining in the packet,
6560 * display one and get a response.
6562 if (s
->curr_prompt
< s
->num_prompts
) {
6566 ssh_pkt_getstring(pktin
, &prompt
, &prompt_len
);
6567 if (prompt_len
> 0) {
6568 static const char trunc
[] = "<prompt truncated>: ";
6569 static const int prlen
= sizeof(s
->pwprompt
) -
6571 if (prompt_len
> prlen
) {
6572 memcpy(s
->pwprompt
, prompt
, prlen
);
6573 strcpy(s
->pwprompt
+ prlen
, trunc
);
6575 memcpy(s
->pwprompt
, prompt
, prompt_len
);
6576 s
->pwprompt
[prompt_len
] = '\0';
6580 "<server failed to send prompt>: ");
6582 s
->echo
= ssh2_pkt_getbool(pktin
);
6588 if (!s
->method
&& s
->can_passwd
) {
6589 s
->method
= AUTH_PASSWORD
;
6590 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
6591 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
6592 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
6599 if (!ssh_get_line(s
->pwprompt
, s
->password
,
6600 sizeof(s
->password
), TRUE
)) {
6602 * get_line failed to get a password (for
6603 * example because one was supplied on the
6604 * command line which has already failed to
6607 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6608 ssh2_pkt_adduint32(s
->pktout
,SSH2_DISCONNECT_BY_APPLICATION
);
6609 ssh2_pkt_addstring(s
->pktout
, "No more passwords available"
6611 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6612 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6613 logevent("Unable to authenticate");
6614 connection_fatal(ssh
->frontend
,
6615 "Unable to authenticate");
6616 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6620 int ret
; /* need not be saved across crReturn */
6621 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
6624 setup_userpass_input(ssh
, s
->password
,
6625 sizeof(s
->password
), s
->echo
);
6627 crWaitUntilV(!pktin
);
6628 ret
= process_userpass_input(ssh
, in
, inlen
);
6632 c_write_str(ssh
, "\r\n");
6636 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
6638 * We have our passphrase. Now try the actual authentication.
6640 struct ssh2_userkey
*key
;
6641 const char *error
= NULL
;
6643 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
,
6645 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
6646 if (key
== SSH2_WRONG_PASSPHRASE
) {
6647 c_write_str(ssh
, "Wrong passphrase\r\n");
6648 s
->tried_pubkey_config
= FALSE
;
6650 c_write_str(ssh
, "Unable to load private key (");
6651 c_write_str(ssh
, error
);
6652 c_write_str(ssh
, ")\r\n");
6653 s
->tried_pubkey_config
= TRUE
;
6655 /* Send a spurious AUTH_NONE to return to the top. */
6656 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6657 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6658 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6659 ssh2_pkt_addstring(s
->pktout
, "none"); /* method */
6660 ssh2_pkt_send(ssh
, s
->pktout
);
6661 s
->type
= AUTH_TYPE_NONE
;
6663 unsigned char *pkblob
, *sigblob
, *sigdata
;
6664 int pkblob_len
, sigblob_len
, sigdata_len
;
6668 * We have loaded the private key and the server
6669 * has announced that it's willing to accept it.
6670 * Hallelujah. Generate a signature and send it.
6672 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6673 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6674 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6675 ssh2_pkt_addstring(s
->pktout
, "publickey"); /* method */
6676 ssh2_pkt_addbool(s
->pktout
, TRUE
);
6677 ssh2_pkt_addstring(s
->pktout
, key
->alg
->name
);
6678 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
6679 ssh2_pkt_addstring_start(s
->pktout
);
6680 ssh2_pkt_addstring_data(s
->pktout
, (char *)pkblob
, pkblob_len
);
6683 * The data to be signed is:
6687 * followed by everything so far placed in the
6690 sigdata_len
= s
->pktout
->length
- 5 + 4 + 20;
6691 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
6693 sigdata
= snewn(sigdata_len
, unsigned char);
6695 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
6696 PUT_32BIT(sigdata
+p
, 20);
6699 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
6700 memcpy(sigdata
+p
, s
->pktout
->data
+ 5,
6701 s
->pktout
->length
- 5);
6702 p
+= s
->pktout
->length
- 5;
6703 assert(p
== sigdata_len
);
6704 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
6705 sigdata_len
, &sigblob_len
);
6706 ssh2_add_sigblob(ssh
, s
->pktout
, pkblob
, pkblob_len
,
6707 sigblob
, sigblob_len
);
6712 ssh2_pkt_send(ssh
, s
->pktout
);
6713 s
->type
= AUTH_TYPE_PUBLICKEY
;
6714 key
->alg
->freekey(key
->data
);
6716 } else if (s
->method
== AUTH_PASSWORD
) {
6718 * We send the password packet lumped tightly together with
6719 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6720 * string long enough to make the total length of the two
6721 * packets constant. This should ensure that a passive
6722 * listener doing traffic analyis can't work out the length
6725 * For this to work, we need an assumption about the
6726 * maximum length of the password packet. I think 256 is
6727 * pretty conservative. Anyone using a password longer than
6728 * that probably doesn't have much to worry about from
6729 * people who find out how long their password is!
6731 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
6732 ssh2_pkt_addstring(s
->pktout
, s
->username
);
6733 ssh2_pkt_addstring(s
->pktout
, "ssh-connection"); /* service requested */
6734 ssh2_pkt_addstring(s
->pktout
, "password");
6735 ssh2_pkt_addbool(s
->pktout
, FALSE
);
6736 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6737 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6738 memset(s
->password
, 0, sizeof(s
->password
));
6739 end_log_omission(ssh
, s
->pktout
);
6740 ssh2_pkt_defer(ssh
, s
->pktout
);
6742 * We'll include a string that's an exact multiple of the
6743 * cipher block size. If the cipher is NULL for some
6744 * reason, we don't do this trick at all because we gain
6747 if (ssh
->cscipher
) {
6750 stringlen
= (256 - ssh
->deferred_len
);
6751 stringlen
+= ssh
->cscipher
->blksize
- 1;
6752 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
6755 * Temporarily disable actual compression,
6756 * so we can guarantee to get this string
6757 * exactly the length we want it. The
6758 * compression-disabling routine should
6759 * return an integer indicating how many
6760 * bytes we should adjust our string length
6764 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
6766 s
->pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
6767 ssh2_pkt_addstring_start(s
->pktout
);
6768 for (i
= 0; i
< stringlen
; i
++) {
6769 char c
= (char) random_byte();
6770 ssh2_pkt_addstring_data(s
->pktout
, &c
, 1);
6772 ssh2_pkt_defer(ssh
, s
->pktout
);
6774 ssh_pkt_defersend(ssh
);
6775 logevent("Sent password");
6776 s
->type
= AUTH_TYPE_PASSWORD
;
6777 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
6778 if (s
->curr_prompt
== 0) {
6779 s
->pktout
= ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE
);
6780 ssh2_pkt_adduint32(s
->pktout
, s
->num_prompts
);
6782 if (s
->need_pw
) { /* only add pw if we just got one! */
6783 dont_log_password(ssh
, s
->pktout
, PKTLOG_BLANK
);
6784 ssh2_pkt_addstring(s
->pktout
, s
->password
);
6785 memset(s
->password
, 0, sizeof(s
->password
));
6786 end_log_omission(ssh
, s
->pktout
);
6789 if (s
->curr_prompt
>= s
->num_prompts
) {
6790 ssh2_pkt_send(ssh
, s
->pktout
);
6793 * If there are prompts remaining, we set
6794 * `gotit' so that we won't attempt to get
6795 * another packet. Then we go back round the
6796 * loop and will end up retrieving another
6797 * prompt out of the existing packet. Funky or
6802 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
6804 c_write_str(ssh
, "No supported authentication methods"
6805 " left to try!\r\n");
6806 logevent("No supported authentications offered."
6808 s
->pktout
= ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
6809 ssh2_pkt_adduint32(s
->pktout
, SSH2_DISCONNECT_BY_APPLICATION
);
6810 ssh2_pkt_addstring(s
->pktout
, "No supported authentication"
6811 " methods available");
6812 ssh2_pkt_addstring(s
->pktout
, "en"); /* language tag */
6813 ssh2_pkt_send_noqueue(ssh
, s
->pktout
);
6814 ssh_closing((Plug
)ssh
, NULL
, 0, 0);
6818 } while (!s
->we_are_in
);
6821 * Now we're authenticated for the connection protocol. The
6822 * connection protocol will automatically have started at this
6823 * point; there's no need to send SERVICE_REQUEST.
6826 ssh
->channels
= newtree234(ssh_channelcmp
);
6829 * Set up handlers for some connection protocol messages, so we
6830 * don't have to handle them repeatedly in this coroutine.
6832 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] =
6833 ssh2_msg_channel_window_adjust
;
6834 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] =
6835 ssh2_msg_global_request
;
6838 * Create the main session channel.
6840 if (!ssh
->cfg
.ssh_no_shell
) {
6841 ssh
->mainchan
= snew(struct ssh_channel
);
6842 ssh
->mainchan
->ssh
= ssh
;
6843 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
6844 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
6845 ssh2_pkt_addstring(s
->pktout
, "session");
6846 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->localid
);
6847 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6848 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
6849 ssh2_pkt_adduint32(s
->pktout
, 0x4000UL
); /* our max pkt size */
6850 ssh2_pkt_send(ssh
, s
->pktout
);
6851 crWaitUntilV(pktin
);
6852 if (pktin
->type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
6853 bombout(("Server refused to open a session"));
6855 /* FIXME: error data comes back in FAILURE packet */
6857 if (ssh_pkt_getuint32(pktin
) != ssh
->mainchan
->localid
) {
6858 bombout(("Server's channel confirmation cited wrong channel"));
6861 ssh
->mainchan
->remoteid
= ssh_pkt_getuint32(pktin
);
6862 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
6863 ssh
->mainchan
->closes
= 0;
6864 ssh
->mainchan
->v
.v2
.remwindow
= ssh_pkt_getuint32(pktin
);
6865 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh_pkt_getuint32(pktin
);
6866 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
6867 add234(ssh
->channels
, ssh
->mainchan
);
6868 update_specials_menu(ssh
->frontend
);
6869 logevent("Opened channel for session");
6871 ssh
->mainchan
= NULL
;
6874 * Now we have a channel, make dispatch table entries for
6875 * general channel-based messages.
6877 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] =
6878 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] =
6879 ssh2_msg_channel_data
;
6880 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = ssh2_msg_channel_eof
;
6881 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = ssh2_msg_channel_close
;
6882 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] =
6883 ssh2_msg_channel_open_confirmation
;
6884 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] =
6885 ssh2_msg_channel_open_failure
;
6886 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] =
6887 ssh2_msg_channel_request
;
6888 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] =
6889 ssh2_msg_channel_open
;
6892 * Potentially enable X11 forwarding.
6894 if (ssh
->mainchan
&& ssh
->cfg
.x11_forward
) {
6895 char proto
[20], data
[64];
6896 logevent("Requesting X11 forwarding");
6897 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
6898 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
6899 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
6900 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6901 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6902 ssh2_pkt_addstring(s
->pktout
, "x11-req");
6903 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6904 ssh2_pkt_addbool(s
->pktout
, 0); /* many connections */
6905 ssh2_pkt_addstring(s
->pktout
, proto
);
6906 ssh2_pkt_addstring(s
->pktout
, data
);
6907 ssh2_pkt_adduint32(s
->pktout
, x11_get_screen_number(ssh
->cfg
.x11_display
));
6908 ssh2_pkt_send(ssh
, s
->pktout
);
6910 crWaitUntilV(pktin
);
6912 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6913 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6914 bombout(("Unexpected response to X11 forwarding request:"
6915 " packet type %d", pktin
->type
));
6918 logevent("X11 forwarding refused");
6920 logevent("X11 forwarding enabled");
6921 ssh
->X11_fwd_enabled
= TRUE
;
6926 * Enable port forwardings.
6928 ssh_setup_portfwd(ssh
, &ssh
->cfg
);
6931 * Potentially enable agent forwarding.
6933 if (ssh
->mainchan
&& ssh
->cfg
.agentfwd
&& agent_exists()) {
6934 logevent("Requesting OpenSSH-style agent forwarding");
6935 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6936 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
6937 ssh2_pkt_addstring(s
->pktout
, "auth-agent-req@openssh.com");
6938 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6939 ssh2_pkt_send(ssh
, s
->pktout
);
6941 crWaitUntilV(pktin
);
6943 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6944 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6945 bombout(("Unexpected response to agent forwarding request:"
6946 " packet type %d", pktin
->type
));
6949 logevent("Agent forwarding refused");
6951 logevent("Agent forwarding enabled");
6952 ssh
->agentfwd_enabled
= TRUE
;
6957 * Now allocate a pty for the session.
6959 if (ssh
->mainchan
&& !ssh
->cfg
.nopty
) {
6960 /* Unpick the terminal-speed string. */
6961 /* XXX perhaps we should allow no speeds to be sent. */
6962 ssh
->ospeed
= 38400; ssh
->ispeed
= 38400; /* last-resort defaults */
6963 sscanf(ssh
->cfg
.termspeed
, "%d,%d", &ssh
->ospeed
, &ssh
->ispeed
);
6964 /* Build the pty request. */
6965 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
6966 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
6967 ssh2_pkt_addstring(s
->pktout
, "pty-req");
6968 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
6969 ssh2_pkt_addstring(s
->pktout
, ssh
->cfg
.termtype
);
6970 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_width
);
6971 ssh2_pkt_adduint32(s
->pktout
, ssh
->term_height
);
6972 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel width */
6973 ssh2_pkt_adduint32(s
->pktout
, 0); /* pixel height */
6974 ssh2_pkt_addstring_start(s
->pktout
);
6975 ssh2_pkt_addbyte(s
->pktout
, 128); /* TTY_OP_ISPEED */
6976 ssh2_pkt_adduint32(s
->pktout
, ssh
->ispeed
);
6977 ssh2_pkt_addbyte(s
->pktout
, 129); /* TTY_OP_OSPEED */
6978 ssh2_pkt_adduint32(s
->pktout
, ssh
->ospeed
);
6979 ssh2_pkt_addstring_data(s
->pktout
, "\0", 1); /* TTY_OP_END */
6980 ssh2_pkt_send(ssh
, s
->pktout
);
6981 ssh
->state
= SSH_STATE_INTERMED
;
6983 crWaitUntilV(pktin
);
6985 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
6986 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
6987 bombout(("Unexpected response to pty request:"
6988 " packet type %d", pktin
->type
));
6991 c_write_str(ssh
, "Server refused to allocate pty\r\n");
6992 ssh
->editing
= ssh
->echoing
= 1;
6994 logeventf(ssh
, "Allocated pty (ospeed %dbps, ispeed %dbps)",
6995 ssh
->ospeed
, ssh
->ispeed
);
6998 ssh
->editing
= ssh
->echoing
= 1;
7002 * Send environment variables.
7004 * Simplest thing here is to send all the requests at once, and
7005 * then wait for a whole bunch of successes or failures.
7007 if (ssh
->mainchan
&& *ssh
->cfg
.environmt
) {
7008 char *e
= ssh
->cfg
.environmt
;
7009 char *var
, *varend
, *val
;
7015 while (*e
&& *e
!= '\t') e
++;
7017 if (*e
== '\t') e
++;
7022 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7023 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
);
7024 ssh2_pkt_addstring(s
->pktout
, "env");
7025 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7026 ssh2_pkt_addstring_start(s
->pktout
);
7027 ssh2_pkt_addstring_data(s
->pktout
, var
, varend
-var
);
7028 ssh2_pkt_addstring(s
->pktout
, val
);
7029 ssh2_pkt_send(ssh
, s
->pktout
);
7034 logeventf(ssh
, "Sent %d environment variables", s
->num_env
);
7037 s
->env_left
= s
->num_env
;
7039 while (s
->env_left
> 0) {
7040 crWaitUntilV(pktin
);
7042 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7043 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7044 bombout(("Unexpected response to environment request:"
7045 " packet type %d", pktin
->type
));
7055 if (s
->env_ok
== s
->num_env
) {
7056 logevent("All environment variables successfully set");
7057 } else if (s
->env_ok
== 0) {
7058 logevent("All environment variables refused");
7059 c_write_str(ssh
, "Server refused to set environment variables\r\n");
7061 logeventf(ssh
, "%d environment variables refused",
7062 s
->num_env
- s
->env_ok
);
7063 c_write_str(ssh
, "Server refused to set all environment variables\r\n");
7068 * Start a shell or a remote command. We may have to attempt
7069 * this twice if the config data has provided a second choice
7072 if (ssh
->mainchan
) while (1) {
7076 if (ssh
->fallback_cmd
) {
7077 subsys
= ssh
->cfg
.ssh_subsys2
;
7078 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
7080 subsys
= ssh
->cfg
.ssh_subsys
;
7081 cmd
= ssh
->cfg
.remote_cmd_ptr
;
7084 s
->pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7085 ssh2_pkt_adduint32(s
->pktout
, ssh
->mainchan
->remoteid
); /* recipient channel */
7087 ssh2_pkt_addstring(s
->pktout
, "subsystem");
7088 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7089 ssh2_pkt_addstring(s
->pktout
, cmd
);
7091 ssh2_pkt_addstring(s
->pktout
, "exec");
7092 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7093 ssh2_pkt_addstring(s
->pktout
, cmd
);
7095 ssh2_pkt_addstring(s
->pktout
, "shell");
7096 ssh2_pkt_addbool(s
->pktout
, 1); /* want reply */
7098 ssh2_pkt_send(ssh
, s
->pktout
);
7100 crWaitUntilV(pktin
);
7102 if (pktin
->type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
7103 if (pktin
->type
!= SSH2_MSG_CHANNEL_FAILURE
) {
7104 bombout(("Unexpected response to shell/command request:"
7105 " packet type %d", pktin
->type
));
7109 * We failed to start the command. If this is the
7110 * fallback command, we really are finished; if it's
7111 * not, and if the fallback command exists, try falling
7112 * back to it before complaining.
7114 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
7115 logevent("Primary command failed; attempting fallback");
7116 ssh
->fallback_cmd
= TRUE
;
7119 bombout(("Server refused to start a shell/command"));
7122 logevent("Started a shell/command");
7127 ssh
->state
= SSH_STATE_SESSION
;
7128 if (ssh
->size_needed
)
7129 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
7130 if (ssh
->eof_needed
)
7131 ssh_special(ssh
, TS_EOF
);
7137 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
7142 s
->try_send
= FALSE
;
7146 * _All_ the connection-layer packets we expect to
7147 * receive are now handled by the dispatch table.
7148 * Anything that reaches here must be bogus.
7151 bombout(("Strange packet received: type %d", pktin
->type
));
7153 } else if (ssh
->mainchan
) {
7155 * We have spare data. Add it to the channel buffer.
7157 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
7162 struct ssh_channel
*c
;
7164 * Try to send data on all channels if we can.
7166 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
7169 continue; /* don't send on closing channels */
7170 bufsize
= ssh2_try_send(c
);
7173 case CHAN_MAINSESSION
:
7174 /* stdin need not receive an unthrottle
7175 * notification since it will be polled */
7178 x11_unthrottle(c
->u
.x11
.s
);
7181 /* agent sockets are request/response and need no
7182 * buffer management */
7185 pfd_unthrottle(c
->u
.pfd
.s
);
7197 * Handlers for SSH2 messages that might arrive at any moment.
7199 void ssh2_msg_disconnect(Ssh ssh
, struct Packet
*pktin
)
7201 /* log reason code in disconnect message */
7203 int nowlen
, reason
, msglen
;
7205 reason
= ssh_pkt_getuint32(pktin
);
7206 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7208 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
7209 buf
= dupprintf("Received disconnect message (%s)",
7210 ssh2_disconnect_reasons
[reason
]);
7212 buf
= dupprintf("Received disconnect message (unknown"
7213 " type %d)", reason
);
7217 buf
= dupprintf("Disconnection message text: %n%.*s",
7218 &nowlen
, msglen
, msg
);
7220 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7222 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
7223 ssh2_disconnect_reasons
[reason
] : "unknown",
7228 void ssh2_msg_debug(Ssh ssh
, struct Packet
*pktin
)
7230 /* log the debug message */
7235 /* XXX maybe we should actually take notice of this */
7236 always_display
= ssh2_pkt_getbool(pktin
);
7237 ssh_pkt_getstring(pktin
, &msg
, &msglen
);
7239 buf
= dupprintf("Remote debug message: %.*s", msglen
, msg
);
7244 void ssh2_msg_something_unimplemented(Ssh ssh
, struct Packet
*pktin
)
7246 struct Packet
*pktout
;
7247 pktout
= ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED
);
7248 ssh2_pkt_adduint32(pktout
, pktin
->sequence
);
7250 * UNIMPLEMENTED messages MUST appear in the same order as the
7251 * messages they respond to. Hence, never queue them.
7253 ssh2_pkt_send_noqueue(ssh
, pktout
);
7257 * Handle the top-level SSH2 protocol.
7259 static void ssh2_protocol_setup(Ssh ssh
)
7264 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7266 for (i
= 0; i
< 256; i
++)
7267 ssh
->packet_dispatch
[i
] = ssh2_msg_something_unimplemented
;
7270 * Any message we actually understand, we set to NULL so that
7271 * the coroutines will get it.
7273 ssh
->packet_dispatch
[SSH2_MSG_UNIMPLEMENTED
] = NULL
;
7274 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_REQUEST
] = NULL
;
7275 ssh
->packet_dispatch
[SSH2_MSG_SERVICE_ACCEPT
] = NULL
;
7276 ssh
->packet_dispatch
[SSH2_MSG_KEXINIT
] = NULL
;
7277 ssh
->packet_dispatch
[SSH2_MSG_NEWKEYS
] = NULL
;
7278 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_INIT
] = NULL
;
7279 ssh
->packet_dispatch
[SSH2_MSG_KEXDH_REPLY
] = NULL
;
7280 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7281 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7282 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_INIT
] = NULL
;
7283 ssh
->packet_dispatch
[SSH2_MSG_KEX_DH_GEX_REPLY
] = NULL
;
7284 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_REQUEST
] = NULL
;
7285 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_FAILURE
] = NULL
;
7286 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_SUCCESS
] = NULL
;
7287 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_BANNER
] = NULL
;
7288 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_PK_OK
] = NULL
;
7289 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7290 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7291 ssh
->packet_dispatch
[SSH2_MSG_USERAUTH_INFO_RESPONSE
] = NULL
;
7292 ssh
->packet_dispatch
[SSH2_MSG_GLOBAL_REQUEST
] = NULL
;
7293 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_SUCCESS
] = NULL
;
7294 ssh
->packet_dispatch
[SSH2_MSG_REQUEST_FAILURE
] = NULL
;
7295 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN
] = NULL
;
7296 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
] = NULL
;
7297 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_OPEN_FAILURE
] = NULL
;
7298 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_WINDOW_ADJUST
] = NULL
;
7299 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_DATA
] = NULL
;
7300 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EXTENDED_DATA
] = NULL
;
7301 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_EOF
] = NULL
;
7302 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_CLOSE
] = NULL
;
7303 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_REQUEST
] = NULL
;
7304 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_SUCCESS
] = NULL
;
7305 ssh
->packet_dispatch
[SSH2_MSG_CHANNEL_FAILURE
] = NULL
;
7308 * These special message types we install handlers for.
7310 ssh
->packet_dispatch
[SSH2_MSG_DISCONNECT
] = ssh2_msg_disconnect
;
7311 ssh
->packet_dispatch
[SSH2_MSG_IGNORE
] = ssh_msg_ignore
; /* shared with ssh1 */
7312 ssh
->packet_dispatch
[SSH2_MSG_DEBUG
] = ssh2_msg_debug
;
7315 static void ssh2_timer(void *ctx
, long now
)
7319 if (!ssh
->kex_in_progress
&& ssh
->cfg
.ssh_rekey_time
!= 0 &&
7320 now
- ssh
->next_rekey
>= 0) {
7321 do_ssh2_transport(ssh
, "timeout", -1, NULL
);
7325 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
,
7326 struct Packet
*pktin
)
7328 if (ssh
->state
== SSH_STATE_CLOSED
)
7332 ssh
->incoming_data_size
+= pktin
->encrypted_len
;
7333 if (!ssh
->kex_in_progress
&&
7334 ssh
->max_data_size
!= 0 &&
7335 ssh
->incoming_data_size
> ssh
->max_data_size
)
7336 do_ssh2_transport(ssh
, "too much data received", -1, NULL
);
7339 if (pktin
&& ssh
->packet_dispatch
[pktin
->type
]) {
7340 ssh
->packet_dispatch
[pktin
->type
](ssh
, pktin
);
7344 if (!ssh
->protocol_initial_phase_done
||
7345 (pktin
&& pktin
->type
>= 20 && pktin
->type
< 50)) {
7346 if (do_ssh2_transport(ssh
, in
, inlen
, pktin
) &&
7347 !ssh
->protocol_initial_phase_done
) {
7348 ssh
->protocol_initial_phase_done
= TRUE
;
7350 * Allow authconn to initialise itself.
7352 do_ssh2_authconn(ssh
, NULL
, 0, NULL
);
7355 do_ssh2_authconn(ssh
, in
, inlen
, pktin
);
7360 * Called to set up the connection.
7362 * Returns an error message, or NULL on success.
7364 static const char *ssh_init(void *frontend_handle
, void **backend_handle
,
7366 char *host
, int port
, char **realhost
, int nodelay
,
7372 ssh
= snew(struct ssh_tag
);
7373 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7374 ssh
->version
= 0; /* when not ready yet */
7377 ssh
->v1_cipher_ctx
= NULL
;
7378 ssh
->crcda_ctx
= NULL
;
7379 ssh
->cscipher
= NULL
;
7380 ssh
->cs_cipher_ctx
= NULL
;
7381 ssh
->sccipher
= NULL
;
7382 ssh
->sc_cipher_ctx
= NULL
;
7384 ssh
->cs_mac_ctx
= NULL
;
7386 ssh
->sc_mac_ctx
= NULL
;
7388 ssh
->cs_comp_ctx
= NULL
;
7390 ssh
->sc_comp_ctx
= NULL
;
7392 ssh
->kex_ctx
= NULL
;
7393 ssh
->hostkey
= NULL
;
7395 ssh
->state
= SSH_STATE_PREPACKET
;
7396 ssh
->size_needed
= FALSE
;
7397 ssh
->eof_needed
= FALSE
;
7400 ssh
->deferred_send_data
= NULL
;
7401 ssh
->deferred_len
= 0;
7402 ssh
->deferred_size
= 0;
7403 ssh
->fallback_cmd
= 0;
7405 ssh
->x11auth
= NULL
;
7406 ssh
->v1_compressing
= FALSE
;
7407 ssh
->v2_outgoing_sequence
= 0;
7408 ssh
->ssh1_rdpkt_crstate
= 0;
7409 ssh
->ssh2_rdpkt_crstate
= 0;
7410 ssh
->do_ssh_init_crstate
= 0;
7411 ssh
->ssh_gotdata_crstate
= 0;
7412 ssh
->do_ssh1_connection_crstate
= 0;
7413 ssh
->do_ssh1_login_crstate
= 0;
7414 ssh
->do_ssh2_transport_crstate
= 0;
7415 ssh
->do_ssh2_authconn_crstate
= 0;
7416 ssh
->do_ssh_init_state
= NULL
;
7417 ssh
->do_ssh1_login_state
= NULL
;
7418 ssh
->do_ssh2_transport_state
= NULL
;
7419 ssh
->do_ssh2_authconn_state
= NULL
;
7420 ssh
->mainchan
= NULL
;
7421 ssh
->throttled_all
= 0;
7422 ssh
->v1_stdout_throttling
= 0;
7424 ssh
->queuelen
= ssh
->queuesize
= 0;
7425 ssh
->queueing
= FALSE
;
7426 ssh
->qhead
= ssh
->qtail
= NULL
;
7427 ssh
->deferred_rekey_reason
= NULL
;
7429 *backend_handle
= ssh
;
7432 if (crypto_startup() == 0)
7433 return "Microsoft high encryption pack not installed!";
7436 ssh
->frontend
= frontend_handle
;
7437 ssh
->term_width
= ssh
->cfg
.width
;
7438 ssh
->term_height
= ssh
->cfg
.height
;
7440 ssh
->channels
= NULL
;
7441 ssh
->rportfwds
= NULL
;
7442 ssh
->portfwds
= NULL
;
7447 ssh
->v1_throttle_count
= 0;
7448 ssh
->overall_bufsize
= 0;
7449 ssh
->fallback_cmd
= 0;
7451 ssh
->protocol
= NULL
;
7453 ssh
->protocol_initial_phase_done
= FALSE
;
7457 ssh
->incoming_data_size
= ssh
->outgoing_data_size
=
7458 ssh
->deferred_data_size
= 0L;
7459 ssh
->max_data_size
= parse_blocksize(ssh
->cfg
.ssh_rekey_data
);
7460 ssh
->kex_in_progress
= FALSE
;
7462 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
, keepalive
);
7471 static void ssh_free(void *handle
)
7473 Ssh ssh
= (Ssh
) handle
;
7474 struct ssh_channel
*c
;
7475 struct ssh_rportfwd
*pf
;
7477 if (ssh
->v1_cipher_ctx
)
7478 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
7479 if (ssh
->cs_cipher_ctx
)
7480 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
7481 if (ssh
->sc_cipher_ctx
)
7482 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
7483 if (ssh
->cs_mac_ctx
)
7484 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
7485 if (ssh
->sc_mac_ctx
)
7486 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
7487 if (ssh
->cs_comp_ctx
) {
7489 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
7491 zlib_compress_cleanup(ssh
->cs_comp_ctx
);
7493 if (ssh
->sc_comp_ctx
) {
7495 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
7497 zlib_decompress_cleanup(ssh
->sc_comp_ctx
);
7500 dh_cleanup(ssh
->kex_ctx
);
7501 sfree(ssh
->savedhost
);
7503 while (ssh
->queuelen
-- > 0)
7504 ssh_free_packet(ssh
->queue
[ssh
->queuelen
]);
7507 while (ssh
->qhead
) {
7508 struct queued_handler
*qh
= ssh
->qhead
;
7509 ssh
->qhead
= qh
->next
;
7512 ssh
->qhead
= ssh
->qtail
= NULL
;
7514 if (ssh
->channels
) {
7515 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
7518 if (c
->u
.x11
.s
!= NULL
)
7519 x11_close(c
->u
.x11
.s
);
7522 if (c
->u
.pfd
.s
!= NULL
)
7523 pfd_close(c
->u
.pfd
.s
);
7528 freetree234(ssh
->channels
);
7529 ssh
->channels
= NULL
;
7532 if (ssh
->rportfwds
) {
7533 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
7535 freetree234(ssh
->rportfwds
);
7536 ssh
->rportfwds
= NULL
;
7538 sfree(ssh
->deferred_send_data
);
7540 x11_free_auth(ssh
->x11auth
);
7541 sfree(ssh
->do_ssh_init_state
);
7542 sfree(ssh
->do_ssh1_login_state
);
7543 sfree(ssh
->do_ssh2_transport_state
);
7544 sfree(ssh
->do_ssh2_authconn_state
);
7545 if (ssh
->crcda_ctx
) {
7546 crcda_free_context(ssh
->crcda_ctx
);
7547 ssh
->crcda_ctx
= NULL
;
7551 expire_timer_context(ssh
);
7553 pinger_free(ssh
->pinger
);
7560 * Reconfigure the SSH backend.
7562 static void ssh_reconfig(void *handle
, Config
*cfg
)
7564 Ssh ssh
= (Ssh
) handle
;
7565 char *rekeying
= NULL
, rekey_mandatory
= FALSE
;
7566 unsigned long old_max_data_size
;
7568 pinger_reconfig(ssh
->pinger
, &ssh
->cfg
, cfg
);
7569 ssh_setup_portfwd(ssh
, cfg
);
7571 if (ssh
->cfg
.ssh_rekey_time
!= cfg
->ssh_rekey_time
&&
7572 cfg
->ssh_rekey_time
!= 0) {
7573 long new_next
= ssh
->last_rekey
+ cfg
->ssh_rekey_time
*60*TICKSPERSEC
;
7574 long now
= GETTICKCOUNT();
7576 if (new_next
- now
< 0) {
7577 rekeying
= "timeout shortened";
7579 ssh
->next_rekey
= schedule_timer(new_next
- now
, ssh2_timer
, ssh
);
7583 old_max_data_size
= ssh
->max_data_size
;
7584 ssh
->max_data_size
= parse_blocksize(cfg
->ssh_rekey_data
);
7585 if (old_max_data_size
!= ssh
->max_data_size
&&
7586 ssh
->max_data_size
!= 0) {
7587 if (ssh
->outgoing_data_size
> ssh
->max_data_size
||
7588 ssh
->incoming_data_size
> ssh
->max_data_size
)
7589 rekeying
= "data limit lowered";
7592 if (ssh
->cfg
.compression
!= cfg
->compression
) {
7593 rekeying
= "compression setting changed";
7594 rekey_mandatory
= TRUE
;
7597 if (ssh
->cfg
.ssh2_des_cbc
!= cfg
->ssh2_des_cbc
||
7598 memcmp(ssh
->cfg
.ssh_cipherlist
, cfg
->ssh_cipherlist
,
7599 sizeof(ssh
->cfg
.ssh_cipherlist
))) {
7600 rekeying
= "cipher settings changed";
7601 rekey_mandatory
= TRUE
;
7604 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
7607 if (!ssh
->kex_in_progress
) {
7608 do_ssh2_transport(ssh
, rekeying
, -1, NULL
);
7609 } else if (rekey_mandatory
) {
7610 ssh
->deferred_rekey_reason
= rekeying
;
7616 * Called to send data down the Telnet connection.
7618 static int ssh_send(void *handle
, char *buf
, int len
)
7620 Ssh ssh
= (Ssh
) handle
;
7622 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7625 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
7627 return ssh_sendbuffer(ssh
);
7631 * Called to query the current amount of buffered stdin data.
7633 static int ssh_sendbuffer(void *handle
)
7635 Ssh ssh
= (Ssh
) handle
;
7638 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
7642 * If the SSH socket itself has backed up, add the total backup
7643 * size on that to any individual buffer on the stdin channel.
7646 if (ssh
->throttled_all
)
7647 override_value
= ssh
->overall_bufsize
;
7649 if (ssh
->version
== 1) {
7650 return override_value
;
7651 } else if (ssh
->version
== 2) {
7652 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
7653 return override_value
;
7655 return (override_value
+
7656 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
7663 * Called to set the size of the window from SSH's POV.
7665 static void ssh_size(void *handle
, int width
, int height
)
7667 Ssh ssh
= (Ssh
) handle
;
7668 struct Packet
*pktout
;
7670 ssh
->term_width
= width
;
7671 ssh
->term_height
= height
;
7673 switch (ssh
->state
) {
7674 case SSH_STATE_BEFORE_SIZE
:
7675 case SSH_STATE_PREPACKET
:
7676 case SSH_STATE_CLOSED
:
7677 break; /* do nothing */
7678 case SSH_STATE_INTERMED
:
7679 ssh
->size_needed
= TRUE
; /* buffer for later */
7681 case SSH_STATE_SESSION
:
7682 if (!ssh
->cfg
.nopty
) {
7683 if (ssh
->version
== 1) {
7684 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
7685 PKT_INT
, ssh
->term_height
,
7686 PKT_INT
, ssh
->term_width
,
7687 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
7688 } else if (ssh
->mainchan
) {
7689 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7690 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7691 ssh2_pkt_addstring(pktout
, "window-change");
7692 ssh2_pkt_addbool(pktout
, 0);
7693 ssh2_pkt_adduint32(pktout
, ssh
->term_width
);
7694 ssh2_pkt_adduint32(pktout
, ssh
->term_height
);
7695 ssh2_pkt_adduint32(pktout
, 0);
7696 ssh2_pkt_adduint32(pktout
, 0);
7697 ssh2_pkt_send(ssh
, pktout
);
7705 * Return a list of the special codes that make sense in this
7708 static const struct telnet_special
*ssh_get_specials(void *handle
)
7710 static const struct telnet_special ssh1_ignore_special
[] = {
7711 {"IGNORE message", TS_NOP
}
7713 static const struct telnet_special ssh2_transport_specials
[] = {
7714 {"IGNORE message", TS_NOP
},
7715 {"Repeat key exchange", TS_REKEY
},
7717 static const struct telnet_special ssh2_session_specials
[] = {
7720 /* These are the signal names defined by draft-ietf-secsh-connect-23.
7721 * They include all the ISO C signals, but are a subset of the POSIX
7722 * required signals. */
7723 {"SIGINT (Interrupt)", TS_SIGINT
},
7724 {"SIGTERM (Terminate)", TS_SIGTERM
},
7725 {"SIGKILL (Kill)", TS_SIGKILL
},
7726 {"SIGQUIT (Quit)", TS_SIGQUIT
},
7727 {"SIGHUP (Hangup)", TS_SIGHUP
},
7728 {"More signals", TS_SUBMENU
},
7729 {"SIGABRT", TS_SIGABRT
}, {"SIGALRM", TS_SIGALRM
},
7730 {"SIGFPE", TS_SIGFPE
}, {"SIGILL", TS_SIGILL
},
7731 {"SIGPIPE", TS_SIGPIPE
}, {"SIGSEGV", TS_SIGSEGV
},
7732 {"SIGUSR1", TS_SIGUSR1
}, {"SIGUSR2", TS_SIGUSR2
},
7735 static const struct telnet_special specials_end
[] = {
7738 /* XXX review this length for any changes: */
7739 static struct telnet_special ssh_specials
[lenof(ssh2_transport_specials
) +
7740 lenof(ssh2_session_specials
) +
7741 lenof(specials_end
)];
7742 Ssh ssh
= (Ssh
) handle
;
7744 #define ADD_SPECIALS(name) \
7746 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7747 memcpy(&ssh_specials[i], name, sizeof name); \
7751 if (ssh
->version
== 1) {
7752 /* Don't bother offering IGNORE if we've decided the remote
7753 * won't cope with it, since we wouldn't bother sending it if
7755 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7756 ADD_SPECIALS(ssh1_ignore_special
);
7757 } else if (ssh
->version
== 2) {
7758 ADD_SPECIALS(ssh2_transport_specials
);
7760 ADD_SPECIALS(ssh2_session_specials
);
7761 } /* else we're not ready yet */
7764 ADD_SPECIALS(specials_end
);
7765 return ssh_specials
;
7773 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7774 * can send an EOF and collect resulting output (e.g. `plink
7777 static void ssh_special(void *handle
, Telnet_Special code
)
7779 Ssh ssh
= (Ssh
) handle
;
7780 struct Packet
*pktout
;
7782 if (code
== TS_EOF
) {
7783 if (ssh
->state
!= SSH_STATE_SESSION
) {
7785 * Buffer the EOF in case we are pre-SESSION, so we can
7786 * send it as soon as we reach SESSION.
7789 ssh
->eof_needed
= TRUE
;
7792 if (ssh
->version
== 1) {
7793 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
7794 } else if (ssh
->mainchan
) {
7795 struct Packet
*pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
7796 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7797 ssh2_pkt_send(ssh
, pktout
);
7799 logevent("Sent EOF message");
7800 } else if (code
== TS_PING
|| code
== TS_NOP
) {
7801 if (ssh
->state
== SSH_STATE_CLOSED
7802 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7803 if (ssh
->version
== 1) {
7804 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
7805 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
7807 pktout
= ssh2_pkt_init(SSH2_MSG_IGNORE
);
7808 ssh2_pkt_addstring_start(pktout
);
7809 ssh2_pkt_send_noqueue(ssh
, pktout
);
7811 } else if (code
== TS_REKEY
) {
7812 if (!ssh
->kex_in_progress
&& ssh
->version
== 2) {
7813 do_ssh2_transport(ssh
, "at user request", -1, NULL
);
7815 } else if (code
== TS_BRK
) {
7816 if (ssh
->state
== SSH_STATE_CLOSED
7817 || ssh
->state
== SSH_STATE_PREPACKET
) return;
7818 if (ssh
->version
== 1) {
7819 logevent("Unable to send BREAK signal in SSH1");
7820 } else if (ssh
->mainchan
) {
7821 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7822 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7823 ssh2_pkt_addstring(pktout
, "break");
7824 ssh2_pkt_addbool(pktout
, 0);
7825 ssh2_pkt_adduint32(pktout
, 0); /* default break length */
7826 ssh2_pkt_send(ssh
, pktout
);
7829 /* Is is a POSIX signal? */
7830 char *signame
= NULL
;
7831 if (code
== TS_SIGABRT
) signame
= "ABRT";
7832 if (code
== TS_SIGALRM
) signame
= "ALRM";
7833 if (code
== TS_SIGFPE
) signame
= "FPE";
7834 if (code
== TS_SIGHUP
) signame
= "HUP";
7835 if (code
== TS_SIGILL
) signame
= "ILL";
7836 if (code
== TS_SIGINT
) signame
= "INT";
7837 if (code
== TS_SIGKILL
) signame
= "KILL";
7838 if (code
== TS_SIGPIPE
) signame
= "PIPE";
7839 if (code
== TS_SIGQUIT
) signame
= "QUIT";
7840 if (code
== TS_SIGSEGV
) signame
= "SEGV";
7841 if (code
== TS_SIGTERM
) signame
= "TERM";
7842 if (code
== TS_SIGUSR1
) signame
= "USR1";
7843 if (code
== TS_SIGUSR2
) signame
= "USR2";
7844 /* The SSH-2 protocol does in principle support arbitrary named
7845 * signals, including signame@domain, but we don't support those. */
7847 /* It's a signal. */
7848 if (ssh
->version
== 2 && ssh
->mainchan
) {
7849 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
7850 ssh2_pkt_adduint32(pktout
, ssh
->mainchan
->remoteid
);
7851 ssh2_pkt_addstring(pktout
, "signal");
7852 ssh2_pkt_addbool(pktout
, 0);
7853 ssh2_pkt_addstring(pktout
, signame
);
7854 ssh2_pkt_send(ssh
, pktout
);
7855 logeventf(ssh
, "Sent signal SIG%s", signame
);
7858 /* Never heard of it. Do nothing */
7863 void *new_sock_channel(void *handle
, Socket s
)
7865 Ssh ssh
= (Ssh
) handle
;
7866 struct ssh_channel
*c
;
7867 c
= snew(struct ssh_channel
);
7871 c
->remoteid
= -1; /* to be set when open confirmed */
7872 c
->localid
= alloc_channel_id(ssh
);
7874 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
7876 bufchain_init(&c
->v
.v2
.outbuffer
);
7877 add234(ssh
->channels
, c
);
7883 * This is called when stdout/stderr (the entity to which
7884 * from_backend sends data) manages to clear some backlog.
7886 static void ssh_unthrottle(void *handle
, int bufsize
)
7888 Ssh ssh
= (Ssh
) handle
;
7889 if (ssh
->version
== 1) {
7890 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
7891 ssh
->v1_stdout_throttling
= 0;
7892 ssh1_throttle(ssh
, -1);
7895 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
7896 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
7900 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
7902 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
7904 struct Packet
*pktout
;
7906 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
7908 if (ssh
->version
== 1) {
7909 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
7910 PKT_INT
, c
->localid
,
7913 /* PKT_STR, <org:orgport>, */
7916 pktout
= ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
7917 ssh2_pkt_addstring(pktout
, "direct-tcpip");
7918 ssh2_pkt_adduint32(pktout
, c
->localid
);
7919 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
7920 ssh2_pkt_adduint32(pktout
, c
->v
.v2
.locwindow
);/* our window size */
7921 ssh2_pkt_adduint32(pktout
, 0x4000UL
); /* our max pkt size */
7922 ssh2_pkt_addstring(pktout
, hostname
);
7923 ssh2_pkt_adduint32(pktout
, port
);
7925 * We make up values for the originator data; partly it's
7926 * too much hassle to keep track, and partly I'm not
7927 * convinced the server should be told details like that
7928 * about my local network configuration.
7930 ssh2_pkt_addstring(pktout
, "client-side-connection");
7931 ssh2_pkt_adduint32(pktout
, 0);
7932 ssh2_pkt_send(ssh
, pktout
);
7936 static Socket
ssh_socket(void *handle
)
7938 Ssh ssh
= (Ssh
) handle
;
7942 static int ssh_sendok(void *handle
)
7944 Ssh ssh
= (Ssh
) handle
;
7945 return ssh
->send_ok
;
7948 static int ssh_ldisc(void *handle
, int option
)
7950 Ssh ssh
= (Ssh
) handle
;
7951 if (option
== LD_ECHO
)
7952 return ssh
->echoing
;
7953 if (option
== LD_EDIT
)
7954 return ssh
->editing
;
7958 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
7960 Ssh ssh
= (Ssh
) handle
;
7964 static void ssh_provide_logctx(void *handle
, void *logctx
)
7966 Ssh ssh
= (Ssh
) handle
;
7967 ssh
->logctx
= logctx
;
7970 static int ssh_return_exitcode(void *handle
)
7972 Ssh ssh
= (Ssh
) handle
;
7976 return (ssh
->exitcode
>= 0 ? ssh
->exitcode
: 0);
7980 * cfg_info for SSH is the currently running version of the
7981 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
7983 static int ssh_cfg_info(void *handle
)
7985 Ssh ssh
= (Ssh
) handle
;
7986 return ssh
->version
;
7990 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7991 * that fails. This variable is the means by which scp.c can reach
7992 * into the SSH code and find out which one it got.
7994 extern int ssh_fallback_cmd(void *handle
)
7996 Ssh ssh
= (Ssh
) handle
;
7997 return ssh
->fallback_cmd
;
8000 Backend ssh_backend
= {
8010 ssh_return_exitcode
,