18 #define logevent(s) { logevent(s); \
19 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
20 fprintf(stderr, "%s\n", s); }
22 #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \
23 (s ? sk_close(s), s = NULL : 0), \
24 connection_fatal msg )
26 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
27 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
28 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
29 #define SSH1_CMSG_USER 4 /* 0x4 */
30 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
31 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
32 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
33 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
34 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
35 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
36 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
37 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
38 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
39 #define SSH1_SMSG_FAILURE 15 /* 0xf */
40 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
41 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
42 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
43 #define SSH1_CMSG_EOF 19 /* 0x13 */
44 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
45 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
46 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
47 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
48 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
49 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
50 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
51 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
52 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
53 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
54 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
55 #define SSH1_MSG_IGNORE 32 /* 0x20 */
56 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
57 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
58 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
59 #define SSH1_MSG_DEBUG 36 /* 0x24 */
60 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
61 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
62 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
63 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
64 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
65 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
66 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
68 #define SSH1_AUTH_TIS 5 /* 0x5 */
69 #define SSH1_AUTH_CCARD 16 /* 0x10 */
71 #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
72 #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
73 #define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
74 #define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
75 #define SSH_AGENT_FAILURE 5 /* 0x5 */
76 #define SSH_AGENT_SUCCESS 6 /* 0x6 */
77 #define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
78 #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
80 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
81 #define SSH2_MSG_IGNORE 2 /* 0x2 */
82 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
83 #define SSH2_MSG_DEBUG 4 /* 0x4 */
84 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
85 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
86 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
87 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
88 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
89 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
90 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
91 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
92 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
93 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
94 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
95 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
96 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
97 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
98 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
99 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
100 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
101 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
102 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
103 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
104 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
105 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
106 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
107 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
108 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
109 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
110 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
111 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
112 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
113 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
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 */
127 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
128 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
129 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
130 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
132 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
134 #define GET_32BIT(cp) \
135 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
136 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
137 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
138 ((unsigned long)(unsigned char)(cp)[3]))
140 #define PUT_32BIT(cp, value) { \
141 (cp)[0] = (unsigned char)((value) >> 24); \
142 (cp)[1] = (unsigned char)((value) >> 16); \
143 (cp)[2] = (unsigned char)((value) >> 8); \
144 (cp)[3] = (unsigned char)(value); }
146 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
148 /* Coroutine mechanics for the sillier bits of the code */
149 #define crBegin1 static int crLine = 0;
150 #define crBegin2 switch(crLine) { case 0:;
151 #define crBegin crBegin1; crBegin2;
152 #define crFinish(z) } crLine = 0; return (z)
153 #define crFinishV } crLine = 0; return
154 #define crReturn(z) \
156 crLine=__LINE__; return (z); case __LINE__:;\
160 crLine=__LINE__; return; case __LINE__:;\
162 #define crStop(z) do{ crLine = 0; return (z); }while(0)
163 #define crStopV do{ crLine = 0; return; }while(0)
164 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
165 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
167 extern const struct ssh_cipher ssh_3des
;
168 extern const struct ssh_cipher ssh_3des_ssh2
;
169 extern const struct ssh_cipher ssh_des
;
170 extern const struct ssh_cipher ssh_aes128_ssh2
;
171 extern const struct ssh_cipher ssh_aes192_ssh2
;
172 extern const struct ssh_cipher ssh_aes256_ssh2
;
173 extern const struct ssh_cipher ssh_blowfish_ssh1
;
174 extern const struct ssh_cipher ssh_blowfish_ssh2
;
176 extern char *x11_init (Socket
*, char *, void *);
177 extern void x11_close (Socket
);
178 extern void x11_send (Socket
, char *, int);
179 extern void x11_invent_auth(char *, int, char *, int);
182 * Ciphers for SSH2. We miss out single-DES because it isn't
183 * supported; also 3DES and Blowfish are both done differently from
184 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
185 * endianness and different-sized keys.)
187 const static struct ssh_cipher
*ciphers
[] = {
195 extern const struct ssh_kex ssh_diffiehellman
;
196 extern const struct ssh_kex ssh_diffiehellman_gex
;
197 const static struct ssh_kex
*kex_algs
[] = {
198 #ifdef DO_DIFFIE_HELLMAN_GEX
199 &ssh_diffiehellman_gex
,
201 &ssh_diffiehellman
};
203 extern const struct ssh_signkey ssh_dss
;
204 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_dss
};
206 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
208 static void nullmac_key(unsigned char *key
) { }
209 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
210 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
211 const static struct ssh_mac ssh_mac_none
= {
212 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
214 const static struct ssh_mac
*macs
[] = {
215 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
216 const static struct ssh_mac
*buggymacs
[] = {
217 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
219 static void ssh_comp_none_init(void) { }
220 static int ssh_comp_none_block(unsigned char *block
, int len
,
221 unsigned char **outblock
, int *outlen
) {
224 const static struct ssh_compress ssh_comp_none
= {
226 ssh_comp_none_init
, ssh_comp_none_block
,
227 ssh_comp_none_init
, ssh_comp_none_block
229 extern const struct ssh_compress ssh_zlib
;
230 const static struct ssh_compress
*compressions
[] = {
231 &ssh_zlib
, &ssh_comp_none
};
233 enum { /* channel types */
240 * 2-3-4 tree storing channels.
243 unsigned remoteid
, localid
;
246 struct ssh2_data_channel
{
247 unsigned char *outbuffer
;
248 unsigned outbuflen
, outbufsize
;
249 unsigned remwindow
, remmaxpkt
;
252 struct ssh_agent_channel
{
253 unsigned char *message
;
254 unsigned char msglen
[4];
255 int lensofar
, totallen
;
257 struct ssh_x11_channel
{
272 static SHA_State exhash
, exhashbase
;
274 static Socket s
= NULL
;
276 static unsigned char session_key
[32];
277 static int ssh1_compressing
;
278 static int ssh_agentfwd_enabled
;
279 static int ssh_X11_fwd_enabled
;
280 static const struct ssh_cipher
*cipher
= NULL
;
281 static const struct ssh_cipher
*cscipher
= NULL
;
282 static const struct ssh_cipher
*sccipher
= NULL
;
283 static const struct ssh_mac
*csmac
= NULL
;
284 static const struct ssh_mac
*scmac
= NULL
;
285 static const struct ssh_compress
*cscomp
= NULL
;
286 static const struct ssh_compress
*sccomp
= NULL
;
287 static const struct ssh_kex
*kex
= NULL
;
288 static const struct ssh_signkey
*hostkey
= NULL
;
289 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
291 static char *savedhost
;
292 static int savedport
;
293 static int ssh_send_ok
;
294 static int ssh_echoing
, ssh_editing
;
296 static tree234
*ssh_channels
; /* indexed by local id */
297 static struct ssh_channel
*mainchan
; /* primary session channel */
301 SSH_STATE_BEFORE_SIZE
,
305 } ssh_state
= SSH_STATE_PREPACKET
;
307 static int size_needed
= FALSE
, eof_needed
= FALSE
;
309 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
310 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
311 static unsigned char *deferred_send_data
= NULL
;
312 static int deferred_len
= 0, deferred_size
= 0;
314 static int ssh_version
;
315 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
316 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
317 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
318 static void ssh_size(void);
319 static void ssh_special (Telnet_Special
);
320 static void ssh2_try_send(struct ssh_channel
*c
);
321 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
323 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
325 static struct rdpkt1_state_tag
{
326 long len
, pad
, biglen
, to_read
;
327 unsigned long realcrc
, gotcrc
;
333 static struct rdpkt2_state_tag
{
334 long len
, pad
, payload
, packetlen
, maclen
;
337 unsigned long incoming_sequence
;
340 static int ssh_channelcmp(void *av
, void *bv
) {
341 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
342 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
343 if (a
->localid
< b
->localid
) return -1;
344 if (a
->localid
> b
->localid
) return +1;
347 static int ssh_channelfind(void *av
, void *bv
) {
348 unsigned *a
= (unsigned *)av
;
349 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
350 if (*a
< b
->localid
) return -1;
351 if (*a
> b
->localid
) return +1;
355 static void c_write (char *buf
, int len
) {
356 if ((flags
& FLAG_STDERR
)) {
358 for (i
= 0; i
< len
; i
++)
360 fputc(buf
[i
], stderr
);
363 from_backend(1, buf
, len
);
367 * Collect incoming data in the incoming packet buffer.
368 * Decipher and verify the packet when it is completely read.
369 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
370 * Update the *data and *datalen variables.
371 * Return the additional nr of bytes needed, or 0 when
372 * a complete packet is available.
374 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
376 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
385 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
386 while ((*datalen
) == 0)
388 st
->len
= (st
->len
<< 8) + **data
;
389 (*data
)++, (*datalen
)--;
393 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
394 st
->len
= 0x300; /* big enough to carry to end */
398 st
->pad
= 8 - (st
->len
% 8);
399 st
->biglen
= st
->len
+ st
->pad
;
400 pktin
.length
= st
->len
- 5;
402 if (pktin
.maxlen
< st
->biglen
) {
403 pktin
.maxlen
= st
->biglen
;
404 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
405 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
407 fatalbox("Out of memory");
410 st
->to_read
= st
->biglen
;
412 while (st
->to_read
> 0) {
413 st
->chunk
= st
->to_read
;
414 while ((*datalen
) == 0)
415 crReturn(st
->to_read
);
416 if (st
->chunk
> (*datalen
))
417 st
->chunk
= (*datalen
);
418 memcpy(st
->p
, *data
, st
->chunk
);
420 *datalen
-= st
->chunk
;
422 st
->to_read
-= st
->chunk
;
426 cipher
->decrypt(pktin
.data
, st
->biglen
);
428 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
429 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
430 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
434 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
435 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
436 if (st
->gotcrc
!= st
->realcrc
) {
437 bombout(("Incorrect CRC received on packet"));
441 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
443 if (ssh1_compressing
) {
444 unsigned char *decompblk
;
448 debug(("Packet payload pre-decompression:\n"));
449 for (i
= -1; i
< pktin
.length
; i
++)
450 debug((" %02x", (unsigned char)pktin
.body
[i
]));
453 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
454 &decompblk
, &decomplen
);
456 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
457 pktin
.maxlen
= st
->pad
+ decomplen
;
458 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
459 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
461 fatalbox("Out of memory");
464 memcpy(pktin
.body
-1, decompblk
, decomplen
);
466 pktin
.length
= decomplen
-1;
468 debug(("Packet payload post-decompression:\n"));
469 for (i
= -1; i
< pktin
.length
; i
++)
470 debug((" %02x", (unsigned char)pktin
.body
[i
]));
475 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
476 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
477 pktin
.type
== SSH1_MSG_DEBUG
||
478 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
479 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
480 long strlen
= GET_32BIT(pktin
.body
);
481 if (strlen
+ 4 != pktin
.length
) {
482 bombout(("Received data packet with bogus string length"));
487 pktin
.type
= pktin
.body
[-1];
489 if (pktin
.type
== SSH1_MSG_DEBUG
) {
490 /* log debug message */
492 int strlen
= GET_32BIT(pktin
.body
);
493 strcpy(buf
, "Remote: ");
494 if (strlen
> 70) strlen
= 70;
495 memcpy(buf
+8, pktin
.body
+4, strlen
);
496 buf
[8+strlen
] = '\0';
499 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
507 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
509 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
517 st
->cipherblk
= sccipher
->blksize
;
520 if (st
->cipherblk
< 8)
523 if (pktin
.maxlen
< st
->cipherblk
) {
524 pktin
.maxlen
= st
->cipherblk
;
525 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
526 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
528 fatalbox("Out of memory");
532 * Acquire and decrypt the first block of the packet. This will
533 * contain the length and padding details.
535 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
536 while ((*datalen
) == 0)
537 crReturn(st
->cipherblk
-st
->i
);
538 pktin
.data
[st
->i
] = *(*data
)++;
542 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
547 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
550 * Now get the length and padding figures.
552 st
->len
= GET_32BIT(pktin
.data
);
553 st
->pad
= pktin
.data
[4];
556 * This enables us to deduce the payload length.
558 st
->payload
= st
->len
- st
->pad
- 1;
560 pktin
.length
= st
->payload
+ 5;
563 * So now we can work out the total packet length.
565 st
->packetlen
= st
->len
+ 4;
566 st
->maclen
= scmac ? scmac
->len
: 0;
569 * Adjust memory allocation if packet is too big.
571 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
572 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
573 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
574 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
576 fatalbox("Out of memory");
580 * Read and decrypt the remainder of the packet.
582 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
583 while ((*datalen
) == 0)
584 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
585 pktin
.data
[st
->i
] = *(*data
)++;
588 /* Decrypt everything _except_ the MAC. */
590 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
591 st
->packetlen
- st
->cipherblk
);
594 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
595 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
596 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
603 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
604 bombout(("Incorrect MAC received on packet"));
607 st
->incoming_sequence
++; /* whether or not we MACed */
610 * Decompress packet payload.
613 unsigned char *newpayload
;
615 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
616 &newpayload
, &newlen
)) {
617 if (pktin
.maxlen
< newlen
+5) {
618 pktin
.maxlen
= newlen
+5;
619 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
620 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
622 fatalbox("Out of memory");
624 pktin
.length
= 5 + newlen
;
625 memcpy(pktin
.data
+5, newpayload
, newlen
);
627 debug(("Post-decompression payload:\r\n"));
628 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
629 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
638 pktin
.type
= pktin
.data
[5];
640 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
641 goto next_packet
; /* FIXME: print DEBUG message */
646 static void ssh1_pktout_size(int len
) {
649 len
+= 5; /* type and CRC */
653 pktout
.length
= len
-5;
654 if (pktout
.maxlen
< biglen
) {
655 pktout
.maxlen
= biglen
;
657 /* Allocate enough buffer space for extra block
658 * for MS CryptEncrypt() */
659 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
660 srealloc(pktout
.data
, biglen
+12));
662 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
663 srealloc(pktout
.data
, biglen
+4));
666 fatalbox("Out of memory");
668 pktout
.body
= pktout
.data
+4+pad
+1;
671 static void s_wrpkt_start(int type
, int len
) {
672 ssh1_pktout_size(len
);
676 static void s_wrpkt(void) {
677 int pad
, len
, biglen
, i
;
680 pktout
.body
[-1] = pktout
.type
;
682 if (ssh1_compressing
) {
683 unsigned char *compblk
;
686 debug(("Packet payload pre-compression:\n"));
687 for (i
= -1; i
< pktout
.length
; i
++)
688 debug((" %02x", (unsigned char)pktout
.body
[i
]));
691 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
693 ssh1_pktout_size(complen
-1);
694 memcpy(pktout
.body
-1, compblk
, complen
);
697 debug(("Packet payload post-compression:\n"));
698 for (i
= -1; i
< pktout
.length
; i
++)
699 debug((" %02x", (unsigned char)pktout
.body
[i
]));
704 len
= pktout
.length
+ 5; /* type and CRC */
708 for (i
=0; i
<pad
; i
++)
709 pktout
.data
[i
+4] = random_byte();
710 crc
= crc32(pktout
.data
+4, biglen
-4);
711 PUT_32BIT(pktout
.data
+biglen
, crc
);
712 PUT_32BIT(pktout
.data
, len
);
715 debug(("Sending packet len=%d\r\n", biglen
+4));
716 for (i
= 0; i
< biglen
+4; i
++)
717 debug((" %02x", (unsigned char)pktout
.data
[i
]));
721 cipher
->encrypt(pktout
.data
+4, biglen
);
723 sk_write(s
, pktout
.data
, biglen
+4);
727 * Construct a packet with the specified contents and
728 * send it to the server.
730 static void send_packet(int pkttype
, ...)
733 unsigned char *p
, *argp
, argchar
;
734 unsigned long argint
;
735 int pktlen
, argtype
, arglen
;
739 va_start(args
, pkttype
);
740 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
743 (void) va_arg(args
, int);
747 (void) va_arg(args
, char);
751 (void) va_arg(args
, unsigned char *);
752 arglen
= va_arg(args
, int);
756 argp
= va_arg(args
, unsigned char *);
757 arglen
= strlen(argp
);
758 pktlen
+= 4 + arglen
;
761 bn
= va_arg(args
, Bignum
);
762 pktlen
+= ssh1_bignum_length(bn
);
770 s_wrpkt_start(pkttype
, pktlen
);
773 va_start(args
, pkttype
);
774 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
777 argint
= va_arg(args
, int);
778 PUT_32BIT(p
, argint
);
782 argchar
= va_arg(args
, unsigned char);
787 argp
= va_arg(args
, unsigned char *);
788 arglen
= va_arg(args
, int);
789 memcpy(p
, argp
, arglen
);
793 argp
= va_arg(args
, unsigned char *);
794 arglen
= strlen(argp
);
795 PUT_32BIT(p
, arglen
);
796 memcpy(p
+ 4, argp
, arglen
);
800 bn
= va_arg(args
, Bignum
);
801 p
+= ssh1_write_bignum(p
, bn
);
810 static int ssh_versioncmp(char *a
, char *b
) {
812 unsigned long av
, bv
;
814 av
= strtoul(a
, &ae
, 10);
815 bv
= strtoul(b
, &be
, 10);
816 if (av
!= bv
) return (av
< bv ?
-1 : +1);
817 if (*ae
== '.') ae
++;
818 if (*be
== '.') be
++;
819 av
= strtoul(ae
, &ae
, 10);
820 bv
= strtoul(be
, &be
, 10);
821 if (av
!= bv
) return (av
< bv ?
-1 : +1);
827 * Utility routines for putting an SSH-protocol `string' and
828 * `uint32' into a SHA state.
831 static void sha_string(SHA_State
*s
, void *str
, int len
) {
832 unsigned char lenblk
[4];
833 PUT_32BIT(lenblk
, len
);
834 SHA_Bytes(s
, lenblk
, 4);
835 SHA_Bytes(s
, str
, len
);
838 static void sha_uint32(SHA_State
*s
, unsigned i
) {
839 unsigned char intblk
[4];
840 PUT_32BIT(intblk
, i
);
841 SHA_Bytes(s
, intblk
, 4);
845 * SSH2 packet construction functions.
847 static void ssh2_pkt_ensure(int length
) {
848 if (pktout
.maxlen
< length
) {
849 pktout
.maxlen
= length
+ 256;
850 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
851 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
853 fatalbox("Out of memory");
856 static void ssh2_pkt_adddata(void *data
, int len
) {
857 pktout
.length
+= len
;
858 ssh2_pkt_ensure(pktout
.length
);
859 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
861 static void ssh2_pkt_addbyte(unsigned char byte
) {
862 ssh2_pkt_adddata(&byte
, 1);
864 static void ssh2_pkt_init(int pkt_type
) {
866 ssh2_pkt_addbyte((unsigned char)pkt_type
);
868 static void ssh2_pkt_addbool(unsigned char value
) {
869 ssh2_pkt_adddata(&value
, 1);
871 static void ssh2_pkt_adduint32(unsigned long value
) {
874 ssh2_pkt_adddata(x
, 4);
876 static void ssh2_pkt_addstring_start(void) {
877 ssh2_pkt_adduint32(0);
878 pktout
.savedpos
= pktout
.length
;
880 static void ssh2_pkt_addstring_str(char *data
) {
881 ssh2_pkt_adddata(data
, strlen(data
));
882 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
883 pktout
.length
- pktout
.savedpos
);
885 static void ssh2_pkt_addstring_data(char *data
, int len
) {
886 ssh2_pkt_adddata(data
, len
);
887 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
888 pktout
.length
- pktout
.savedpos
);
890 static void ssh2_pkt_addstring(char *data
) {
891 ssh2_pkt_addstring_start();
892 ssh2_pkt_addstring_str(data
);
894 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
896 int i
, n
= (ssh1_bignum_bitcount(b
)+7)/8;
899 fatalbox("out of memory");
901 for (i
= 1; i
<= n
; i
++)
902 p
[i
] = bignum_byte(b
, n
-i
);
904 while (i
<= n
&& p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
906 memmove(p
, p
+i
, n
+1-i
);
910 static void ssh2_pkt_addmp(Bignum b
) {
913 p
= ssh2_mpint_fmt(b
, &len
);
914 ssh2_pkt_addstring_start();
915 ssh2_pkt_addstring_data(p
, len
);
920 * Construct an SSH2 final-form packet: compress it, encrypt it,
921 * put the MAC on it. Final packet, ready to be sent, is stored in
922 * pktout.data. Total length is returned.
924 static int ssh2_pkt_construct(void) {
925 int cipherblk
, maclen
, padding
, i
;
926 static unsigned long outgoing_sequence
= 0;
929 * Compress packet payload.
932 debug(("Pre-compression payload:\r\n"));
933 for (i
= 5; i
< pktout
.length
; i
++)
934 debug((" %02x", (unsigned char)pktout
.data
[i
]));
938 unsigned char *newpayload
;
940 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
941 &newpayload
, &newlen
)) {
943 ssh2_pkt_adddata(newpayload
, newlen
);
949 * Add padding. At least four bytes, and must also bring total
950 * length (minus MAC) up to a multiple of the block size.
952 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
953 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
955 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
956 maclen
= csmac ? csmac
->len
: 0;
957 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
958 pktout
.data
[4] = padding
;
959 for (i
= 0; i
< padding
; i
++)
960 pktout
.data
[pktout
.length
+ i
] = random_byte();
961 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
963 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
965 outgoing_sequence
++; /* whether or not we MACed */
968 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
969 for (i
= 0; i
< pktout
.length
+padding
; i
++)
970 debug((" %02x", (unsigned char)pktout
.data
[i
]));
975 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
977 /* Ready-to-send packet starts at pktout.data. We return length. */
978 return pktout
.length
+ padding
+ maclen
;
982 * Construct and send an SSH2 packet immediately.
984 static void ssh2_pkt_send(void) {
985 int len
= ssh2_pkt_construct();
986 sk_write(s
, pktout
.data
, len
);
990 * Construct an SSH2 packet and add it to a deferred data block.
991 * Useful for sending multiple packets in a single sk_write() call,
992 * to prevent a traffic-analysing listener from being able to work
993 * out the length of any particular packet (such as the password
996 * Note that because SSH2 sequence-numbers its packets, this can
997 * NOT be used as an m4-style `defer' allowing packets to be
998 * constructed in one order and sent in another.
1000 static void ssh2_pkt_defer(void) {
1001 int len
= ssh2_pkt_construct();
1002 if (deferred_len
+ len
> deferred_size
) {
1003 deferred_size
= deferred_len
+ len
+ 128;
1004 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1006 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
1007 deferred_len
+= len
;
1011 * Send the whole deferred data block constructed by
1014 static void ssh2_pkt_defersend(void) {
1015 sk_write(s
, deferred_send_data
, deferred_len
);
1016 deferred_len
= deferred_size
= 0;
1017 sfree(deferred_send_data
);
1018 deferred_send_data
= NULL
;
1022 void bndebug(char *string
, Bignum b
) {
1025 p
= ssh2_mpint_fmt(b
, &len
);
1026 debug(("%s", string
));
1027 for (i
= 0; i
< len
; i
++)
1028 debug((" %02x", p
[i
]));
1034 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1037 p
= ssh2_mpint_fmt(b
, &len
);
1038 sha_string(s
, p
, len
);
1043 * SSH2 packet decode functions.
1045 static unsigned long ssh2_pkt_getuint32(void) {
1046 unsigned long value
;
1047 if (pktin
.length
- pktin
.savedpos
< 4)
1048 return 0; /* arrgh, no way to decline (FIXME?) */
1049 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1050 pktin
.savedpos
+= 4;
1053 static void ssh2_pkt_getstring(char **p
, int *length
) {
1055 if (pktin
.length
- pktin
.savedpos
< 4)
1057 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1058 pktin
.savedpos
+= 4;
1059 if (pktin
.length
- pktin
.savedpos
< *length
)
1061 *p
= pktin
.data
+pktin
.savedpos
;
1062 pktin
.savedpos
+= *length
;
1064 static Bignum
ssh2_pkt_getmp(void) {
1069 ssh2_pkt_getstring(&p
, &length
);
1073 bombout(("internal error: Can't handle negative mpints"));
1076 b
= bignum_from_bytes(p
, length
);
1080 static int do_ssh_init(unsigned char c
) {
1082 static char version
[10];
1083 static char vstring
[80];
1084 static char vlog
[sizeof(vstring
)+20];
1089 /* Search for the string "SSH-" in the input. */
1092 static const int transS
[] = { 1, 2, 2, 1 };
1093 static const int transH
[] = { 0, 0, 3, 0 };
1094 static const int transminus
[] = { 0, 0, 0, -1 };
1095 if (c
== 'S') i
= transS
[i
];
1096 else if (c
== 'H') i
= transH
[i
];
1097 else if (c
== '-') i
= transminus
[i
];
1101 crReturn(1); /* get another character */
1104 strcpy(vstring
, "SSH-");
1108 crReturn(1); /* get another char */
1109 if (vsp
< vstring
+sizeof(vstring
)-1)
1115 } else if (i
< sizeof(version
)-1)
1122 ssh_agentfwd_enabled
= FALSE
;
1123 rdpkt2_state
.incoming_sequence
= 0;
1126 sprintf(vlog
, "Server version: %s", vstring
);
1127 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1131 * Server version "1.99" means we can choose whether we use v1
1132 * or v2 protocol. Choice is based on cfg.sshprot.
1134 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1136 * This is a v2 server. Begin v2 protocol.
1138 char *verstring
= "SSH-2.0-PuTTY";
1139 SHA_Init(&exhashbase
);
1141 * Hash our version string and their version string.
1143 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1144 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1145 sprintf(vstring
, "%s\n", verstring
);
1146 sprintf(vlog
, "We claim version: %s", verstring
);
1148 logevent("Using SSH protocol version 2");
1149 sk_write(s
, vstring
, strlen(vstring
));
1150 ssh_protocol
= ssh2_protocol
;
1152 s_rdpkt
= ssh2_rdpkt
;
1155 * This is a v1 server. Begin v1 protocol.
1157 sprintf(vstring
, "SSH-%s-PuTTY\n",
1158 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1159 sprintf(vlog
, "We claim version: %s", vstring
);
1160 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1162 logevent("Using SSH protocol version 1");
1163 sk_write(s
, vstring
, strlen(vstring
));
1164 ssh_protocol
= ssh1_protocol
;
1166 s_rdpkt
= ssh1_rdpkt
;
1168 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1173 static void ssh_gotdata(unsigned char *data
, int datalen
)
1178 * To begin with, feed the characters one by one to the
1179 * protocol initialisation / selection function do_ssh_init().
1180 * When that returns 0, we're done with the initial greeting
1181 * exchange and can move on to packet discipline.
1186 crReturnV
; /* more data please */
1187 ret
= do_ssh_init(*data
);
1194 * We emerge from that loop when the initial negotiation is
1195 * over and we have selected an s_rdpkt function. Now pass
1196 * everything to s_rdpkt, and then pass the resulting packets
1197 * to the proper protocol handler.
1202 while (datalen
> 0) {
1203 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1204 ssh_protocol(NULL
, 0, 1);
1205 if (ssh_state
== SSH_STATE_CLOSED
) {
1215 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1217 /* A socket error has occurred. */
1218 ssh_state
= SSH_STATE_CLOSED
;
1221 connection_fatal(data
);
1224 /* Connection has closed. */
1225 ssh_state
= SSH_STATE_CLOSED
;
1230 ssh_gotdata (data
, len
);
1231 if (ssh_state
== SSH_STATE_CLOSED
) {
1242 * Connect to specified host and port.
1243 * Returns an error message, or NULL on success.
1244 * Also places the canonical host name into `realhost'.
1246 static char *connect_to_host(char *host
, int port
, char **realhost
)
1255 savedhost
= smalloc(1+strlen(host
));
1257 fatalbox("Out of memory");
1258 strcpy(savedhost
, host
);
1261 port
= 22; /* default ssh port */
1274 addr
= sk_namelookup(host
, realhost
);
1275 if ( (err
= sk_addr_error(addr
)) )
1285 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1286 if ( (err
= sk_socket_error(s
)) )
1290 sk_write(s
, "connect ", 8);
1291 sk_write(s
, FWhost
, strlen(FWhost
));
1294 sprintf(buf
, " %d\n", FWport
);
1295 sk_write(s
, buf
, strlen(buf
));
1303 * Handle the key exchange and user authentication phases.
1305 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1308 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1309 unsigned char cookie
[8];
1310 struct RSAKey servkey
, hostkey
;
1311 struct MD5Context md5c
;
1312 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1313 static int tried_publickey
;
1314 static unsigned char session_id
[16];
1316 static char username
[100];
1320 if (!ispkt
) crWaitUntil(ispkt
);
1322 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1323 bombout(("Public key packet not received"));
1327 logevent("Received public keys");
1329 memcpy(cookie
, pktin
.body
, 8);
1331 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1332 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1335 * Log the host key fingerprint.
1339 logevent("Host key fingerprint is:");
1340 strcpy(logmsg
, " ");
1341 hostkey
.comment
= NULL
;
1342 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1347 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1348 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1351 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1352 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1353 MD5Update(&md5c
, pktin
.body
, 8);
1354 MD5Final(session_id
, &md5c
);
1356 for (i
=0; i
<32; i
++)
1357 session_key
[i
] = random_byte();
1359 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1361 rsabuf
= smalloc(len
);
1363 fatalbox("Out of memory");
1366 * Verify the host key.
1370 * First format the key into a string.
1372 int len
= rsastr_len(&hostkey
);
1373 char fingerprint
[100];
1374 char *keystr
= smalloc(len
);
1376 fatalbox("Out of memory");
1377 rsastr_fmt(keystr
, &hostkey
);
1378 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1379 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1383 for (i
=0; i
<32; i
++) {
1384 rsabuf
[i
] = session_key
[i
];
1386 rsabuf
[i
] ^= session_id
[i
];
1389 if (hostkey
.bytes
> servkey
.bytes
) {
1390 rsaencrypt(rsabuf
, 32, &servkey
);
1391 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1393 rsaencrypt(rsabuf
, 32, &hostkey
);
1394 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1397 logevent("Encrypted session key");
1399 cipher_type
= cfg
.cipher
== CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH
:
1400 cfg
.cipher
== CIPHER_DES ? SSH_CIPHER_DES
:
1402 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1403 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1404 cipher_type
= SSH_CIPHER_3DES
;
1406 switch (cipher_type
) {
1407 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1408 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1409 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1412 send_packet(SSH1_CMSG_SESSION_KEY
,
1413 PKT_CHAR
, cipher_type
,
1414 PKT_DATA
, cookie
, 8,
1415 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1416 PKT_DATA
, rsabuf
, len
,
1420 logevent("Trying to enable encryption...");
1424 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1425 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1427 cipher
->sesskey(session_key
);
1431 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1432 bombout(("Encryption not successfully enabled"));
1436 logevent("Successfully started encryption");
1442 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1443 c_write("login as: ", 10);
1446 crWaitUntil(!ispkt
);
1447 while (inlen
--) switch (c
= *in
++) {
1454 c_write("\b \b", 3);
1460 c_write("\b \b", 3);
1469 if (((c
>= ' ' && c
<= '~') ||
1470 ((unsigned char)c
>= 160)) && pos
< 40) {
1471 username
[pos
++] = c
;
1478 username
[strcspn(username
, "\n\r")] = '\0';
1480 strncpy(username
, cfg
.username
, 99);
1481 username
[99] = '\0';
1484 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1486 char userlog
[22+sizeof(username
)];
1487 sprintf(userlog
, "Sent username \"%s\"", username
);
1489 if (flags
& FLAG_INTERACTIVE
&&
1490 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1491 strcat(userlog
, "\r\n");
1492 c_write(userlog
, strlen(userlog
));
1499 tried_publickey
= 0;
1501 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1502 static char password
[100];
1503 static char prompt
[200];
1506 static int pwpkt_type
;
1508 * Show password prompt, having first obtained it via a TIS
1509 * or CryptoCard exchange if we're doing TIS or CryptoCard
1512 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1513 if (agent_exists()) {
1515 * Attempt RSA authentication using Pageant.
1517 static unsigned char request
[5], *response
, *p
;
1518 static int responselen
;
1519 static int i
, nkeys
;
1520 static int authed
= FALSE
;
1523 logevent("Pageant is running. Requesting keys.");
1525 /* Request the keys held by the agent. */
1526 PUT_32BIT(request
, 1);
1527 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1528 agent_query(request
, 5, &r
, &responselen
);
1529 response
= (unsigned char *)r
;
1532 nkeys
= GET_32BIT(p
); p
+= 4;
1533 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1535 for (i
= 0; i
< nkeys
; i
++) {
1536 static struct RSAKey key
;
1537 static Bignum challenge
;
1538 static char *commentp
;
1539 static int commentlen
;
1541 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1544 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1545 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1546 commentlen
= GET_32BIT(p
); p
+= 4;
1547 commentp
= p
; p
+= commentlen
;
1548 send_packet(SSH1_CMSG_AUTH_RSA
,
1549 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1551 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1552 logevent("Key refused");
1555 logevent("Received RSA challenge");
1556 ssh1_read_bignum(pktin
.body
, &challenge
);
1558 char *agentreq
, *q
, *ret
;
1560 len
= 1 + 4; /* message type, bit count */
1561 len
+= ssh1_bignum_length(key
.exponent
);
1562 len
+= ssh1_bignum_length(key
.modulus
);
1563 len
+= ssh1_bignum_length(challenge
);
1564 len
+= 16; /* session id */
1565 len
+= 4; /* response format */
1566 agentreq
= smalloc(4 + len
);
1567 PUT_32BIT(agentreq
, len
);
1569 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1570 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1572 q
+= ssh1_write_bignum(q
, key
.exponent
);
1573 q
+= ssh1_write_bignum(q
, key
.modulus
);
1574 q
+= ssh1_write_bignum(q
, challenge
);
1575 memcpy(q
, session_id
, 16); q
+= 16;
1576 PUT_32BIT(q
, 1); /* response format */
1577 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1580 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1581 logevent("Sending Pageant's response");
1582 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1583 PKT_DATA
, ret
+5, 16, PKT_END
);
1586 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1587 logevent("Pageant's response accepted");
1588 if (flags
& FLAG_VERBOSE
) {
1589 c_write("Authenticated using RSA key \"",
1591 c_write(commentp
, commentlen
);
1592 c_write("\" from agent\r\n", 14);
1596 logevent("Pageant's response not accepted");
1598 logevent("Pageant failed to answer challenge");
1602 logevent("No reply received from Pageant");
1605 freebn(key
.exponent
);
1606 freebn(key
.modulus
);
1615 if (*cfg
.keyfile
&& !tried_publickey
)
1616 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1618 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1620 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1621 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1622 logevent("Requested TIS authentication");
1623 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1625 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1626 logevent("TIS authentication declined");
1627 if (flags
& FLAG_INTERACTIVE
)
1628 c_write("TIS authentication refused.\r\n", 29);
1630 int challengelen
= ((pktin
.body
[0] << 24) |
1631 (pktin
.body
[1] << 16) |
1632 (pktin
.body
[2] << 8) |
1634 logevent("Received TIS challenge");
1635 if (challengelen
> sizeof(prompt
)-1)
1636 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1637 memcpy(prompt
, pktin
.body
+4, challengelen
);
1638 prompt
[challengelen
] = '\0';
1641 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1643 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1644 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1645 logevent("Requested CryptoCard authentication");
1646 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1648 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1649 logevent("CryptoCard authentication declined");
1650 c_write("CryptoCard authentication refused.\r\n", 29);
1652 int challengelen
= ((pktin
.body
[0] << 24) |
1653 (pktin
.body
[1] << 16) |
1654 (pktin
.body
[2] << 8) |
1656 logevent("Received CryptoCard challenge");
1657 if (challengelen
> sizeof(prompt
)-1)
1658 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1659 memcpy(prompt
, pktin
.body
+4, challengelen
);
1660 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1661 sizeof(prompt
)-challengelen
);
1662 prompt
[sizeof(prompt
)-1] = '\0';
1665 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1666 sprintf(prompt
, "%.90s@%.90s's password: ",
1667 username
, savedhost
);
1669 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1670 char *comment
= NULL
;
1671 if (flags
& FLAG_VERBOSE
)
1672 c_write("Trying public key authentication.\r\n", 35);
1673 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1674 if (flags
& FLAG_VERBOSE
)
1675 c_write("No passphrase required.\r\n", 25);
1678 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1682 if (ssh_get_password
) {
1683 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1685 * get_password failed to get a password (for
1686 * example because one was supplied on the command
1687 * line which has already failed to work).
1690 logevent("No more passwords to try");
1691 ssh_state
= SSH_STATE_CLOSED
;
1695 c_write(prompt
, strlen(prompt
));
1699 crWaitUntil(!ispkt
);
1700 while (inlen
--) switch (c
= *in
++) {
1717 if (((c
>= ' ' && c
<= '~') ||
1718 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1719 password
[pos
++] = c
;
1727 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1729 * Try public key authentication with the specified
1732 static struct RSAKey pubkey
;
1733 static Bignum challenge
, response
;
1735 static unsigned char buffer
[32];
1737 tried_publickey
= 1;
1738 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1740 c_write("Couldn't load public key from ", 30);
1741 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1742 c_write(".\r\n", 3);
1743 continue; /* go and try password */
1746 c_write("Wrong passphrase.\r\n", 19);
1747 tried_publickey
= 0;
1748 continue; /* try again */
1752 * Send a public key attempt.
1754 send_packet(SSH1_CMSG_AUTH_RSA
,
1755 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1758 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1759 c_write("Server refused our public key.\r\n", 32);
1760 continue; /* go and try password */
1762 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1763 bombout(("Bizarre response to offer of public key"));
1766 ssh1_read_bignum(pktin
.body
, &challenge
);
1767 response
= rsadecrypt(challenge
, &pubkey
);
1768 freebn(pubkey
.private_exponent
); /* burn the evidence */
1770 for (i
= 0; i
< 32; i
++) {
1771 buffer
[i
] = bignum_byte(response
, 31-i
);
1775 MD5Update(&md5c
, buffer
, 32);
1776 MD5Update(&md5c
, session_id
, 16);
1777 MD5Final(buffer
, &md5c
);
1779 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1780 PKT_DATA
, buffer
, 16, PKT_END
);
1783 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1784 if (flags
& FLAG_VERBOSE
)
1785 c_write("Failed to authenticate with our public key.\r\n",
1787 continue; /* go and try password */
1788 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1789 bombout(("Bizarre response to RSA authentication response"));
1793 break; /* we're through! */
1795 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1797 logevent("Sent password");
1798 memset(password
, 0, strlen(password
));
1800 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1801 if (flags
& FLAG_VERBOSE
)
1802 c_write("Access denied\r\n", 15);
1803 logevent("Authentication refused");
1804 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1805 logevent("Received disconnect request");
1806 ssh_state
= SSH_STATE_CLOSED
;
1808 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1809 bombout(("Strange packet received, type %d", pktin
.type
));
1814 logevent("Authentication successful");
1819 void sshfwd_close(struct ssh_channel
*c
) {
1821 if (ssh_version
== 1) {
1822 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1824 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1825 ssh2_pkt_adduint32(c
->remoteid
);
1829 if (c
->type
== CHAN_X11
) {
1831 logevent("X11 connection terminated");
1836 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1837 if (ssh_version
== 1) {
1838 send_packet(SSH1_MSG_CHANNEL_DATA
,
1839 PKT_INT
, c
->remoteid
,
1844 ssh2_add_channel_data(c
, buf
, len
);
1849 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1854 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1857 if (ssh_state
== SSH_STATE_CLOSED
)
1860 if (cfg
.agentfwd
&& agent_exists()) {
1861 logevent("Requesting agent forwarding");
1862 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1863 do { crReturnV
; } while (!ispkt
);
1864 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1865 bombout(("Protocol confusion"));
1867 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1868 logevent("Agent forwarding refused");
1870 logevent("Agent forwarding enabled");
1871 ssh_agentfwd_enabled
= TRUE
;
1875 if (cfg
.x11_forward
) {
1876 char proto
[20], data
[64];
1877 logevent("Requesting X11 forwarding");
1878 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1879 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1880 PKT_STR
, proto
, PKT_STR
, data
,
1883 do { crReturnV
; } while (!ispkt
);
1884 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1885 bombout(("Protocol confusion"));
1887 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1888 logevent("X11 forwarding refused");
1890 logevent("X11 forwarding enabled");
1891 ssh_X11_fwd_enabled
= TRUE
;
1896 send_packet(SSH1_CMSG_REQUEST_PTY
,
1897 PKT_STR
, cfg
.termtype
,
1898 PKT_INT
, rows
, PKT_INT
, cols
,
1899 PKT_INT
, 0, PKT_INT
, 0,
1902 ssh_state
= SSH_STATE_INTERMED
;
1903 do { crReturnV
; } while (!ispkt
);
1904 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1905 bombout(("Protocol confusion"));
1907 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1908 c_write("Server refused to allocate pty\r\n", 32);
1909 ssh_editing
= ssh_echoing
= 1;
1911 logevent("Allocated pty");
1913 ssh_editing
= ssh_echoing
= 1;
1916 if (cfg
.compression
) {
1917 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1918 do { crReturnV
; } while (!ispkt
);
1919 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1920 bombout(("Protocol confusion"));
1922 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1923 c_write("Server refused to compress\r\n", 32);
1925 logevent("Started compression");
1926 ssh1_compressing
= TRUE
;
1927 zlib_compress_init();
1928 zlib_decompress_init();
1931 if (*cfg
.remote_cmd
)
1932 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1934 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1935 logevent("Started session");
1937 ssh_state
= SSH_STATE_SESSION
;
1941 ssh_special(TS_EOF
);
1943 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
1945 ssh_channels
= newtree234(ssh_channelcmp
);
1949 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1950 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1951 long len
= GET_32BIT(pktin
.body
);
1952 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
1954 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1955 ssh_state
= SSH_STATE_CLOSED
;
1956 logevent("Received disconnect request");
1958 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
1959 /* Remote side is trying to open a channel to talk to our
1960 * X-Server. Give them back a local channel number. */
1962 struct ssh_channel
*c
, *d
;
1965 logevent("Received X11 connect request");
1966 /* Refuse if X11 forwarding is disabled. */
1967 if (!ssh_X11_fwd_enabled
) {
1968 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1969 PKT_INT
, GET_32BIT(pktin
.body
),
1971 logevent("Rejected X11 connect request");
1973 c
= smalloc(sizeof(struct ssh_channel
));
1975 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
1976 logevent("opening X11 forward connection failed");
1978 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1979 PKT_INT
, GET_32BIT(pktin
.body
),
1982 logevent("opening X11 forward connection succeeded");
1983 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
1985 break; /* found a free number */
1988 c
->remoteid
= GET_32BIT(pktin
.body
);
1991 c
->type
= CHAN_X11
; /* identify channel type */
1992 add234(ssh_channels
, c
);
1993 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1994 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1996 logevent("Opened X11 forward channel");
1999 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
2000 /* Remote side is trying to open a channel to talk to our
2001 * agent. Give them back a local channel number. */
2003 struct ssh_channel
*c
;
2006 /* Refuse if agent forwarding is disabled. */
2007 if (!ssh_agentfwd_enabled
) {
2008 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2009 PKT_INT
, GET_32BIT(pktin
.body
),
2013 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
2015 break; /* found a free number */
2018 c
= smalloc(sizeof(struct ssh_channel
));
2019 c
->remoteid
= GET_32BIT(pktin
.body
);
2022 c
->type
= CHAN_AGENT
; /* identify channel type */
2023 c
->u
.a
.lensofar
= 0;
2024 add234(ssh_channels
, c
);
2025 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2026 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2029 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2030 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2031 /* Remote side closes a channel. */
2032 unsigned i
= GET_32BIT(pktin
.body
);
2033 struct ssh_channel
*c
;
2034 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2037 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2038 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2039 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2040 logevent("X11 connection closed");
2041 assert(c
->u
.x11
.s
!= NULL
);
2042 x11_close(c
->u
.x11
.s
);
2045 c
->closes
|= closetype
;
2046 if (c
->closes
== 3) {
2047 del234(ssh_channels
, c
);
2051 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2052 /* Data sent down one of our channels. */
2053 int i
= GET_32BIT(pktin
.body
);
2054 int len
= GET_32BIT(pktin
.body
+4);
2055 unsigned char *p
= pktin
.body
+8;
2056 struct ssh_channel
*c
;
2057 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2061 x11_send(c
->u
.x11
.s
, p
, len
);
2064 /* Data for an agent message. Buffer it. */
2066 if (c
->u
.a
.lensofar
< 4) {
2067 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2068 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2069 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2071 if (c
->u
.a
.lensofar
== 4) {
2072 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2073 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2074 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2076 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2077 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2078 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2079 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2081 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2082 void *reply
, *sentreply
;
2084 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2089 /* Fake SSH_AGENT_FAILURE. */
2090 sentreply
= "\0\0\0\1\5";
2093 send_packet(SSH1_MSG_CHANNEL_DATA
,
2094 PKT_INT
, c
->remoteid
,
2096 PKT_DATA
, sentreply
, replylen
,
2100 sfree(c
->u
.a
.message
);
2101 c
->u
.a
.lensofar
= 0;
2107 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2108 /* may be from EXEC_SHELL on some servers */
2109 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2110 /* may be from EXEC_SHELL on some servers
2111 * if no pty is available or in other odd cases. Ignore */
2112 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2113 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2115 bombout(("Strange packet received: type %d", pktin
.type
));
2120 int len
= min(inlen
, 512);
2121 send_packet(SSH1_CMSG_STDIN_DATA
,
2122 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2133 * Utility routine for decoding comma-separated strings in KEXINIT.
2135 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2136 int needlen
= strlen(needle
);
2139 * Is it at the start of the string?
2141 if (haylen
>= needlen
&& /* haystack is long enough */
2142 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2143 (haylen
== needlen
|| haystack
[needlen
] == ',')
2144 /* either , or EOS follows */
2148 * If not, search for the next comma and resume after that.
2149 * If no comma found, terminate.
2151 while (haylen
> 0 && *haystack
!= ',')
2152 haylen
--, haystack
++;
2155 haylen
--, haystack
++; /* skip over comma itself */
2160 * SSH2 key creation method.
2162 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2164 /* First 20 bytes. */
2167 SHA_Bytes(&s
, H
, 20);
2168 SHA_Bytes(&s
, &chr
, 1);
2169 SHA_Bytes(&s
, sessid
, 20);
2170 SHA_Final(&s
, keyspace
);
2171 /* Next 20 bytes. */
2174 SHA_Bytes(&s
, H
, 20);
2175 SHA_Bytes(&s
, keyspace
, 20);
2176 SHA_Final(&s
, keyspace
+20);
2180 * Handle the SSH2 transport layer.
2182 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2184 static int i
, len
, nbits
;
2186 static Bignum p
, g
, e
, f
, K
;
2187 static int kex_init_value
, kex_reply_value
;
2188 static const struct ssh_mac
**maclist
;
2190 static const struct ssh_cipher
*cscipher_tobe
= NULL
;
2191 static const struct ssh_cipher
*sccipher_tobe
= NULL
;
2192 static const struct ssh_mac
*csmac_tobe
= NULL
;
2193 static const struct ssh_mac
*scmac_tobe
= NULL
;
2194 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2195 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2196 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2197 static int hostkeylen
, siglen
;
2198 static void *hkey
; /* actual host key */
2199 static unsigned char exchange_hash
[20];
2200 static unsigned char first_exchange_hash
[20];
2201 static unsigned char keyspace
[40];
2202 static const struct ssh_cipher
*preferred_cipher
;
2203 static const struct ssh_compress
*preferred_comp
;
2204 static int first_kex
;
2211 * Set up the preferred cipher and compression.
2213 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2214 preferred_cipher
= &ssh_blowfish_ssh2
;
2215 } else if (cfg
.cipher
== CIPHER_DES
) {
2216 logevent("Single DES not supported in SSH2; using 3DES");
2217 preferred_cipher
= &ssh_3des_ssh2
;
2218 } else if (cfg
.cipher
== CIPHER_3DES
) {
2219 preferred_cipher
= &ssh_3des_ssh2
;
2221 /* Shouldn't happen, but we do want to initialise to _something_. */
2222 preferred_cipher
= &ssh_3des_ssh2
;
2224 if (cfg
.compression
)
2225 preferred_comp
= &ssh_zlib
;
2227 preferred_comp
= &ssh_comp_none
;
2230 * Be prepared to work around the buggy MAC problem.
2233 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2235 maclist
= macs
, nmacs
= lenof(macs
);
2239 * Construct and send our key exchange packet.
2241 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2242 for (i
= 0; i
< 16; i
++)
2243 ssh2_pkt_addbyte((unsigned char)random_byte());
2244 /* List key exchange algorithms. */
2245 ssh2_pkt_addstring_start();
2246 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2247 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2248 if (i
< lenof(kex_algs
)-1)
2249 ssh2_pkt_addstring_str(",");
2251 /* List server host key algorithms. */
2252 ssh2_pkt_addstring_start();
2253 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2254 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2255 if (i
< lenof(hostkey_algs
)-1)
2256 ssh2_pkt_addstring_str(",");
2258 /* List client->server encryption algorithms. */
2259 ssh2_pkt_addstring_start();
2260 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2261 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2262 ssh2_pkt_addstring_str(c
->name
);
2263 if (i
< lenof(ciphers
))
2264 ssh2_pkt_addstring_str(",");
2266 /* List server->client encryption algorithms. */
2267 ssh2_pkt_addstring_start();
2268 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2269 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2270 ssh2_pkt_addstring_str(c
->name
);
2271 if (i
< lenof(ciphers
))
2272 ssh2_pkt_addstring_str(",");
2274 /* List client->server MAC algorithms. */
2275 ssh2_pkt_addstring_start();
2276 for (i
= 0; i
< nmacs
; i
++) {
2277 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2279 ssh2_pkt_addstring_str(",");
2281 /* List server->client MAC algorithms. */
2282 ssh2_pkt_addstring_start();
2283 for (i
= 0; i
< nmacs
; i
++) {
2284 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2286 ssh2_pkt_addstring_str(",");
2288 /* List client->server compression algorithms. */
2289 ssh2_pkt_addstring_start();
2290 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2291 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2292 ssh2_pkt_addstring_str(c
->name
);
2293 if (i
< lenof(compressions
))
2294 ssh2_pkt_addstring_str(",");
2296 /* List server->client compression algorithms. */
2297 ssh2_pkt_addstring_start();
2298 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2299 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2300 ssh2_pkt_addstring_str(c
->name
);
2301 if (i
< lenof(compressions
))
2302 ssh2_pkt_addstring_str(",");
2304 /* List client->server languages. Empty list. */
2305 ssh2_pkt_addstring_start();
2306 /* List server->client languages. Empty list. */
2307 ssh2_pkt_addstring_start();
2308 /* First KEX packet does _not_ follow, because we're not that brave. */
2309 ssh2_pkt_addbool(FALSE
);
2311 ssh2_pkt_adduint32(0);
2313 exhash
= exhashbase
;
2314 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2318 if (!ispkt
) crWaitUntil(ispkt
);
2319 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2322 * Now examine the other side's KEXINIT to see what we're up
2325 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2326 bombout(("expected key exchange packet from server"));
2329 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2330 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2331 pktin
.savedpos
+= 16; /* skip garbage cookie */
2332 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2333 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2334 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2339 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2340 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2341 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2342 hostkey
= hostkey_algs
[i
];
2346 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2347 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2348 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2349 if (in_commasep_string(c
->name
, str
, len
)) {
2354 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2355 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2356 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2357 if (in_commasep_string(c
->name
, str
, len
)) {
2362 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2363 for (i
= 0; i
< nmacs
; i
++) {
2364 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2365 csmac_tobe
= maclist
[i
];
2369 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2370 for (i
= 0; i
< nmacs
; i
++) {
2371 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2372 scmac_tobe
= maclist
[i
];
2376 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2377 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2378 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2379 if (in_commasep_string(c
->name
, str
, len
)) {
2384 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2385 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2386 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2387 if (in_commasep_string(c
->name
, str
, len
)) {
2394 * If we're doing Diffie-Hellman group exchange, start by
2395 * requesting a group.
2397 if (kex
== &ssh_diffiehellman_gex
) {
2400 logevent("Doing Diffie-Hellman group exchange");
2402 * Work out number of bits. We start with the maximum key
2403 * length of either cipher...
2405 csbits
= cscipher_tobe
->keylen
;
2406 scbits
= sccipher_tobe
->keylen
;
2407 nbits
= (csbits
> scbits ? csbits
: scbits
);
2408 /* The keys only have 160-bit entropy, since they're based on
2409 * a SHA-1 hash. So cap the key size at 160 bits. */
2410 if (nbits
> 160) nbits
= 160;
2412 * ... and then work out how big a DH group we will need to
2413 * allow that much data.
2415 nbits
= 512 << ((nbits
-1) / 64);
2416 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
2417 ssh2_pkt_adduint32(nbits
);
2421 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
2422 bombout(("expected key exchange group packet from server"));
2425 p
= ssh2_pkt_getmp();
2426 g
= ssh2_pkt_getmp();
2427 dh_setup_group(p
, g
);
2428 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
2429 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
2432 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
2433 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
2436 logevent("Doing Diffie-Hellman key exchange");
2438 * Now generate and send e for Diffie-Hellman.
2441 ssh2_pkt_init(kex_init_value
);
2446 if (pktin
.type
!= kex_reply_value
) {
2447 bombout(("expected key exchange reply packet from server"));
2450 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2451 f
= ssh2_pkt_getmp();
2452 ssh2_pkt_getstring(&sigdata
, &siglen
);
2456 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2457 if (kex
== &ssh_diffiehellman_gex
) {
2458 sha_uint32(&exhash
, nbits
);
2459 sha_mpint(&exhash
, p
);
2460 sha_mpint(&exhash
, g
);
2462 sha_mpint(&exhash
, e
);
2463 sha_mpint(&exhash
, f
);
2464 sha_mpint(&exhash
, K
);
2465 SHA_Final(&exhash
, exchange_hash
);
2470 debug(("Exchange hash is:\r\n"));
2471 for (i
= 0; i
< 20; i
++)
2472 debug((" %02x", exchange_hash
[i
]));
2476 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2477 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2478 bombout(("Server failed host key check"));
2483 * Expect SSH2_MSG_NEWKEYS from server.
2486 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2487 bombout(("expected new-keys packet from server"));
2492 * Authenticate remote host: verify host key. (We've already
2493 * checked the signature of the exchange hash.)
2495 keystr
= hostkey
->fmtkey(hkey
);
2496 fingerprint
= hostkey
->fingerprint(hkey
);
2497 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2498 keystr
, fingerprint
);
2499 if (first_kex
) { /* don't bother logging this in rekeys */
2500 logevent("Host key fingerprint is:");
2501 logevent(fingerprint
);
2505 hostkey
->freekey(hkey
);
2508 * Send SSH2_MSG_NEWKEYS.
2510 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2514 * Create and initialise session keys.
2516 cscipher
= cscipher_tobe
;
2517 sccipher
= sccipher_tobe
;
2520 cscomp
= cscomp_tobe
;
2521 sccomp
= sccomp_tobe
;
2522 cscomp
->compress_init();
2523 sccomp
->decompress_init();
2525 * Set IVs after keys. Here we use the exchange hash from the
2526 * _first_ key exchange.
2529 memcpy(first_exchange_hash
, exchange_hash
, sizeof(exchange_hash
));
2530 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'C', keyspace
);
2531 cscipher
->setcskey(keyspace
);
2532 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'D', keyspace
);
2533 sccipher
->setsckey(keyspace
);
2534 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'A', keyspace
);
2535 cscipher
->setcsiv(keyspace
);
2536 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'B', keyspace
);
2537 sccipher
->setsciv(keyspace
);
2538 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'E', keyspace
);
2539 csmac
->setcskey(keyspace
);
2540 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'F', keyspace
);
2541 scmac
->setsckey(keyspace
);
2544 * If this is the first key exchange phase, we must pass the
2545 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2546 * wants to see it but because it will need time to initialise
2547 * itself before it sees an actual packet. In subsequent key
2548 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2549 * it would only confuse the layer above.
2557 * Now we're encrypting. Begin returning 1 to the protocol main
2558 * function so that other things can run on top of the
2559 * transport. If we ever see a KEXINIT, we must go back to the
2562 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2565 logevent("Server initiated key re-exchange");
2566 goto begin_key_exchange
;
2572 * Add data to an SSH2 channel output buffer.
2574 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2575 if (c
->v2
.outbufsize
<
2576 c
->v2
.outbuflen
+ len
) {
2578 c
->v2
.outbuflen
+ len
+ 1024;
2579 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2582 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2584 c
->v2
.outbuflen
+= len
;
2588 * Attempt to send data on an SSH2 channel.
2590 static void ssh2_try_send(struct ssh_channel
*c
) {
2591 while (c
->v2
.remwindow
> 0 &&
2592 c
->v2
.outbuflen
> 0) {
2593 unsigned len
= c
->v2
.remwindow
;
2594 if (len
> c
->v2
.outbuflen
)
2595 len
= c
->v2
.outbuflen
;
2596 if (len
> c
->v2
.remmaxpkt
)
2597 len
= c
->v2
.remmaxpkt
;
2598 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2599 ssh2_pkt_adduint32(c
->remoteid
);
2600 ssh2_pkt_addstring_start();
2601 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2603 c
->v2
.outbuflen
-= len
;
2604 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2606 c
->v2
.remwindow
-= len
;
2611 * Handle the SSH2 userauth and connection layers.
2613 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2615 static unsigned long remote_winsize
;
2616 static unsigned long remote_maxpkt
;
2621 * Request userauth protocol, and await a response to it.
2623 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2624 ssh2_pkt_addstring("ssh-userauth");
2626 crWaitUntilV(ispkt
);
2627 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2628 bombout(("Server refused user authentication protocol"));
2633 * FIXME: currently we support only password authentication.
2634 * (This places us technically in violation of the SSH2 spec.
2635 * We must fix this.)
2639 * Get a username and a password.
2641 static char username
[100];
2642 static char password
[100];
2646 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2647 c_write("login as: ", 10);
2650 crWaitUntilV(!ispkt
);
2651 while (inlen
--) switch (c
= *in
++) {
2658 c_write("\b \b", 3);
2664 c_write("\b \b", 3);
2673 if (((c
>= ' ' && c
<= '~') ||
2674 ((unsigned char)c
>= 160)) && pos
< 40) {
2675 username
[pos
++] = c
;
2682 username
[strcspn(username
, "\n\r")] = '\0';
2685 strncpy(username
, cfg
.username
, 99);
2686 username
[99] = '\0';
2687 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2688 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2689 c_write(stuff
, strlen(stuff
));
2693 if (ssh_get_password
) {
2695 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2696 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2698 * get_password failed to get a password (for
2699 * example because one was supplied on the command
2700 * line which has already failed to work).
2703 logevent("No more passwords to try");
2704 ssh_state
= SSH_STATE_CLOSED
;
2708 c_write("password: ", 10);
2713 crWaitUntilV(!ispkt
);
2714 while (inlen
--) switch (c
= *in
++) {
2731 if (((c
>= ' ' && c
<= '~') ||
2732 ((unsigned char)c
>= 160)) && pos
< 40)
2733 password
[pos
++] = c
;
2741 * We send the password packet lumped tightly together with
2742 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
2743 * string long enough to make the total length of the two
2744 * packets constant. This should ensure that a passive
2745 * listener doing traffic analyis can't work out the length
2748 * For this to work, we need an assumption about the
2749 * maximum length of the password packet. I think 256 is
2750 * pretty conservative. Anyone using a password longer than
2751 * that probably doesn't have much to worry about from
2752 * people who find out how long their password is!
2754 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2755 ssh2_pkt_addstring(username
);
2756 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2757 ssh2_pkt_addstring("password");
2758 ssh2_pkt_addbool(FALSE
);
2759 ssh2_pkt_addstring(password
);
2762 * We'll include a string that's an exact multiple of the
2763 * cipher block size. If the cipher is NULL for some
2764 * reason, we don't do this trick at all because we gain
2769 ssh2_pkt_init(SSH2_MSG_IGNORE
);
2770 ssh2_pkt_addstring_start();
2771 for (i
= deferred_len
; i
<= 256; i
+= cscipher
->blksize
) {
2772 for (j
= 0; j
< cscipher
->blksize
; j
++) {
2773 char c
= (char)random_byte();
2774 ssh2_pkt_addstring_data(&c
, 1);
2779 ssh2_pkt_defersend();
2781 crWaitUntilV(ispkt
);
2782 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2783 c_write("Access denied\r\n", 15);
2784 logevent("Authentication refused");
2790 * Now we're authenticated for the connection protocol. The
2791 * connection protocol will automatically have started at this
2792 * point; there's no need to send SERVICE_REQUEST.
2796 * So now create a channel with a session in it.
2798 mainchan
= smalloc(sizeof(struct ssh_channel
));
2799 mainchan
->localid
= 100; /* as good as any */
2800 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2801 ssh2_pkt_addstring("session");
2802 ssh2_pkt_adduint32(mainchan
->localid
);
2803 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2804 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2806 crWaitUntilV(ispkt
);
2807 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2808 bombout(("Server refused to open a session"));
2810 /* FIXME: error data comes back in FAILURE packet */
2812 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2813 bombout(("Server's channel confirmation cited wrong channel"));
2816 mainchan
->remoteid
= ssh2_pkt_getuint32();
2817 mainchan
->type
= CHAN_MAINSESSION
;
2818 mainchan
->closes
= 0;
2819 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
2820 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2821 mainchan
->v2
.outbuffer
= NULL
;
2822 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
2823 ssh_channels
= newtree234(ssh_channelcmp
);
2824 add234(ssh_channels
, mainchan
);
2825 logevent("Opened channel for session");
2828 * Potentially enable X11 forwarding.
2830 if (cfg
.x11_forward
) {
2831 char proto
[20], data
[64];
2832 logevent("Requesting X11 forwarding");
2833 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2834 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2835 ssh2_pkt_adduint32(mainchan
->remoteid
);
2836 ssh2_pkt_addstring("x11-req");
2837 ssh2_pkt_addbool(1); /* want reply */
2838 ssh2_pkt_addbool(0); /* many connections */
2839 ssh2_pkt_addstring(proto
);
2840 ssh2_pkt_addstring(data
);
2841 ssh2_pkt_adduint32(0); /* screen number */
2845 crWaitUntilV(ispkt
);
2846 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2847 unsigned i
= ssh2_pkt_getuint32();
2848 struct ssh_channel
*c
;
2849 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2851 continue; /* nonexistent channel */
2852 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2854 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2856 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2857 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2858 bombout(("Server got confused by X11 forwarding request"));
2861 logevent("X11 forwarding refused");
2863 logevent("X11 forwarding enabled");
2864 ssh_X11_fwd_enabled
= TRUE
;
2869 * Now allocate a pty for the session.
2872 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2873 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2874 ssh2_pkt_addstring("pty-req");
2875 ssh2_pkt_addbool(1); /* want reply */
2876 ssh2_pkt_addstring(cfg
.termtype
);
2877 ssh2_pkt_adduint32(cols
);
2878 ssh2_pkt_adduint32(rows
);
2879 ssh2_pkt_adduint32(0); /* pixel width */
2880 ssh2_pkt_adduint32(0); /* pixel height */
2881 ssh2_pkt_addstring_start();
2882 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2884 ssh_state
= SSH_STATE_INTERMED
;
2887 crWaitUntilV(ispkt
);
2888 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2889 unsigned i
= ssh2_pkt_getuint32();
2890 struct ssh_channel
*c
;
2891 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2893 continue; /* nonexistent channel */
2894 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2896 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2898 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2899 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2900 bombout(("Server got confused by pty request"));
2903 c_write("Server refused to allocate pty\r\n", 32);
2904 ssh_editing
= ssh_echoing
= 1;
2906 logevent("Allocated pty");
2909 ssh_editing
= ssh_echoing
= 1;
2913 * Start a shell or a remote command.
2915 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2916 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2917 if (cfg
.ssh_subsys
) {
2918 ssh2_pkt_addstring("subsystem");
2919 ssh2_pkt_addbool(1); /* want reply */
2920 ssh2_pkt_addstring(cfg
.remote_cmd
);
2921 } else if (*cfg
.remote_cmd
) {
2922 ssh2_pkt_addstring("exec");
2923 ssh2_pkt_addbool(1); /* want reply */
2924 ssh2_pkt_addstring(cfg
.remote_cmd
);
2926 ssh2_pkt_addstring("shell");
2927 ssh2_pkt_addbool(1); /* want reply */
2931 crWaitUntilV(ispkt
);
2932 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2933 unsigned i
= ssh2_pkt_getuint32();
2934 struct ssh_channel
*c
;
2935 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2937 continue; /* nonexistent channel */
2938 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2940 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2941 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2942 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2943 bombout(("Server got confused by shell/command request"));
2946 bombout(("Server refused to start a shell/command"));
2949 logevent("Started a shell/command");
2952 ssh_state
= SSH_STATE_SESSION
;
2956 ssh_special(TS_EOF
);
2961 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2964 static int try_send
;
2968 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2969 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2972 unsigned i
= ssh2_pkt_getuint32();
2973 struct ssh_channel
*c
;
2974 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2976 continue; /* nonexistent channel */
2977 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2978 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2979 continue; /* extended but not stderr */
2980 ssh2_pkt_getstring(&data
, &length
);
2983 case CHAN_MAINSESSION
:
2984 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
2988 x11_send(c
->u
.x11
.s
, data
, length
);
2992 * Enlarge the window again at the remote
2993 * side, just in case it ever runs down and
2994 * they fail to send us any more data.
2996 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2997 ssh2_pkt_adduint32(c
->remoteid
);
2998 ssh2_pkt_adduint32(length
);
3001 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
3002 ssh_state
= SSH_STATE_CLOSED
;
3003 logevent("Received disconnect message");
3005 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
3006 continue; /* exit status et al; ignore (FIXME?) */
3007 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
3008 unsigned i
= ssh2_pkt_getuint32();
3009 struct ssh_channel
*c
;
3011 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3013 continue; /* nonexistent channel */
3015 if (c
->type
== CHAN_X11
) {
3017 * Remote EOF on an X11 channel means we should
3018 * wrap up and close the channel ourselves.
3020 x11_close(c
->u
.x11
.s
);
3023 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
3024 unsigned i
= ssh2_pkt_getuint32();
3025 struct ssh_channel
*c
;
3028 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3030 continue; /* nonexistent channel */
3031 if (c
->closes
== 0) {
3032 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3033 ssh2_pkt_adduint32(c
->remoteid
);
3036 /* Do pre-close processing on the channel. */
3038 case CHAN_MAINSESSION
:
3039 break; /* nothing to see here, move along */
3043 del234(ssh_channels
, c
);
3044 sfree(c
->v2
.outbuffer
);
3048 * See if that was the last channel left open.
3050 c
= first234(ssh_channels
, &e
);
3052 logevent("All channels closed. Disconnecting");
3053 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3054 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3055 ssh2_pkt_addstring("All open channels closed");
3056 ssh2_pkt_addstring("en"); /* language tag */
3058 ssh_state
= SSH_STATE_CLOSED
;
3061 continue; /* remote sends close; ignore (FIXME) */
3062 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3063 unsigned i
= ssh2_pkt_getuint32();
3064 struct ssh_channel
*c
;
3065 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3067 continue; /* nonexistent channel */
3068 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3070 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3074 struct ssh_channel
*c
;
3075 ssh2_pkt_getstring(&type
, &typelen
);
3076 c
= smalloc(sizeof(struct ssh_channel
));
3078 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3079 if (!ssh_X11_fwd_enabled
)
3080 error
= "X11 forwarding is not enabled";
3081 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3082 error
= "Unable to open an X11 connection";
3087 error
= "Unsupported channel type requested";
3090 c
->remoteid
= ssh2_pkt_getuint32();
3092 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3093 ssh2_pkt_adduint32(c
->remoteid
);
3094 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3095 ssh2_pkt_addstring(error
);
3096 ssh2_pkt_addstring("en"); /* language tag */
3100 struct ssh_channel
*d
;
3104 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3107 break; /* found a free number */
3112 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3113 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3114 c
->v2
.outbuffer
= NULL
;
3115 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3116 add234(ssh_channels
, c
);
3117 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3118 ssh2_pkt_adduint32(c
->remoteid
);
3119 ssh2_pkt_adduint32(c
->localid
);
3120 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3121 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3125 bombout(("Strange packet received: type %d", pktin
.type
));
3130 * We have spare data. Add it to the channel buffer.
3132 ssh2_add_channel_data(mainchan
, in
, inlen
);
3137 struct ssh_channel
*c
;
3139 * Try to send data on all channels if we can.
3141 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3150 * Handle the top-level SSH2 protocol.
3152 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3154 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3156 do_ssh2_authconn(in
, inlen
, ispkt
);
3160 * Called to set up the connection.
3162 * Returns an error message, or NULL on success.
3164 static char *ssh_init (char *host
, int port
, char **realhost
) {
3168 if(crypto_startup() == 0)
3169 return "Microsoft high encryption pack not installed!";
3176 p
= connect_to_host(host
, port
, realhost
);
3184 * Called to send data down the Telnet connection.
3186 static void ssh_send (char *buf
, int len
) {
3187 if (s
== NULL
|| ssh_protocol
== NULL
)
3190 ssh_protocol(buf
, len
, 0);
3194 * Called to set the size of the window from SSH's POV.
3196 static void ssh_size(void) {
3197 switch (ssh_state
) {
3198 case SSH_STATE_BEFORE_SIZE
:
3199 case SSH_STATE_PREPACKET
:
3200 case SSH_STATE_CLOSED
:
3201 break; /* do nothing */
3202 case SSH_STATE_INTERMED
:
3203 size_needed
= TRUE
; /* buffer for later */
3205 case SSH_STATE_SESSION
:
3207 if (ssh_version
== 1) {
3208 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3209 PKT_INT
, rows
, PKT_INT
, cols
,
3210 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3212 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3213 ssh2_pkt_adduint32(mainchan
->remoteid
);
3214 ssh2_pkt_addstring("window-change");
3215 ssh2_pkt_addbool(0);
3216 ssh2_pkt_adduint32(cols
);
3217 ssh2_pkt_adduint32(rows
);
3218 ssh2_pkt_adduint32(0);
3219 ssh2_pkt_adduint32(0);
3228 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3229 * can send an EOF and collect resulting output (e.g. `plink
3232 static void ssh_special (Telnet_Special code
) {
3233 if (code
== TS_EOF
) {
3234 if (ssh_state
!= SSH_STATE_SESSION
) {
3236 * Buffer the EOF in case we are pre-SESSION, so we can
3237 * send it as soon as we reach SESSION.
3243 if (ssh_version
== 1) {
3244 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3246 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3247 ssh2_pkt_adduint32(mainchan
->remoteid
);
3250 logevent("Sent EOF message");
3251 } else if (code
== TS_PING
) {
3252 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3254 if (ssh_version
== 1) {
3255 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3257 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3258 ssh2_pkt_addstring_start();
3266 static Socket
ssh_socket(void) { return s
; }
3268 static int ssh_sendok(void) { return ssh_send_ok
; }
3270 static int ssh_ldisc(int option
) {
3271 if (option
== LD_ECHO
) return ssh_echoing
;
3272 if (option
== LD_EDIT
) return ssh_editing
;
3276 Backend ssh_backend
= {