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_USERAUTH_REQUEST 50 /* 0x32 */
91 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
92 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
93 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
94 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
95 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
96 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
97 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
98 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
99 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
100 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
101 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
102 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
103 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
104 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
105 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
106 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
107 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
108 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
109 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
111 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
112 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
113 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
114 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
115 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
116 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
117 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
118 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
119 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
120 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
121 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
123 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
124 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
125 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
126 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
128 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
130 #define GET_32BIT(cp) \
131 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
132 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
133 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
134 ((unsigned long)(unsigned char)(cp)[3]))
136 #define PUT_32BIT(cp, value) { \
137 (cp)[0] = (unsigned char)((value) >> 24); \
138 (cp)[1] = (unsigned char)((value) >> 16); \
139 (cp)[2] = (unsigned char)((value) >> 8); \
140 (cp)[3] = (unsigned char)(value); }
142 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
144 /* Coroutine mechanics for the sillier bits of the code */
145 #define crBegin1 static int crLine = 0;
146 #define crBegin2 switch(crLine) { case 0:;
147 #define crBegin crBegin1; crBegin2;
148 #define crFinish(z) } crLine = 0; return (z)
149 #define crFinishV } crLine = 0; return
150 #define crReturn(z) \
152 crLine=__LINE__; return (z); case __LINE__:;\
156 crLine=__LINE__; return; case __LINE__:;\
158 #define crStop(z) do{ crLine = 0; return (z); }while(0)
159 #define crStopV do{ crLine = 0; return; }while(0)
160 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
161 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
163 extern const struct ssh_cipher ssh_3des
;
164 extern const struct ssh_cipher ssh_3des_ssh2
;
165 extern const struct ssh_cipher ssh_des
;
166 extern const struct ssh_cipher ssh_blowfish_ssh1
;
167 extern const struct ssh_cipher ssh_blowfish_ssh2
;
169 extern char *x11_init (Socket
*, char *, void *);
170 extern void x11_close (Socket
);
171 extern void x11_send (Socket
, char *, int);
172 extern void x11_invent_auth(char *, int, char *, int);
175 * Ciphers for SSH2. We miss out single-DES because it isn't
176 * supported; also 3DES and Blowfish are both done differently from
177 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
178 * endianness and different-sized keys.)
180 const static struct ssh_cipher
*ciphers
[] = { &ssh_blowfish_ssh2
, &ssh_3des_ssh2
};
182 extern const struct ssh_kex ssh_diffiehellman
;
183 const static struct ssh_kex
*kex_algs
[] = { &ssh_diffiehellman
};
185 extern const struct ssh_signkey ssh_dss
;
186 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_dss
};
188 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
190 static void nullmac_key(unsigned char *key
) { }
191 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
192 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
193 const static struct ssh_mac ssh_mac_none
= {
194 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
196 const static struct ssh_mac
*macs
[] = {
197 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
198 const static struct ssh_mac
*buggymacs
[] = {
199 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
201 static void ssh_comp_none_init(void) { }
202 static int ssh_comp_none_block(unsigned char *block
, int len
,
203 unsigned char **outblock
, int *outlen
) {
206 const static struct ssh_compress ssh_comp_none
= {
208 ssh_comp_none_init
, ssh_comp_none_block
,
209 ssh_comp_none_init
, ssh_comp_none_block
211 extern const struct ssh_compress ssh_zlib
;
212 const static struct ssh_compress
*compressions
[] = {
213 &ssh_zlib
, &ssh_comp_none
};
215 enum { /* channel types */
222 * 2-3-4 tree storing channels.
225 unsigned remoteid
, localid
;
228 struct ssh2_data_channel
{
229 unsigned char *outbuffer
;
230 unsigned outbuflen
, outbufsize
;
231 unsigned remwindow
, remmaxpkt
;
234 struct ssh_agent_channel
{
235 unsigned char *message
;
236 unsigned char msglen
[4];
237 int lensofar
, totallen
;
239 struct ssh_x11_channel
{
254 static SHA_State exhash
, exhashbase
;
256 static Socket s
= NULL
;
258 static unsigned char session_key
[32];
259 static int ssh1_compressing
;
260 static int ssh_agentfwd_enabled
;
261 static int ssh_X11_fwd_enabled
;
262 static const struct ssh_cipher
*cipher
= NULL
;
263 static const struct ssh_cipher
*cscipher
= NULL
;
264 static const struct ssh_cipher
*sccipher
= NULL
;
265 static const struct ssh_mac
*csmac
= NULL
;
266 static const struct ssh_mac
*scmac
= NULL
;
267 static const struct ssh_compress
*cscomp
= NULL
;
268 static const struct ssh_compress
*sccomp
= NULL
;
269 static const struct ssh_kex
*kex
= NULL
;
270 static const struct ssh_signkey
*hostkey
= NULL
;
271 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
273 static char *savedhost
;
274 static int savedport
;
275 static int ssh_send_ok
;
276 static int ssh_echoing
, ssh_editing
;
278 static tree234
*ssh_channels
; /* indexed by local id */
279 static struct ssh_channel
*mainchan
; /* primary session channel */
283 SSH_STATE_BEFORE_SIZE
,
287 } ssh_state
= SSH_STATE_PREPACKET
;
289 static int size_needed
= FALSE
, eof_needed
= FALSE
;
291 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
292 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
293 static unsigned char *deferred_send_data
= NULL
;
294 static int deferred_len
= 0, deferred_size
= 0;
296 static int ssh_version
;
297 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
298 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
299 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
300 static void ssh_size(void);
301 static void ssh_special (Telnet_Special
);
302 static void ssh2_try_send(struct ssh_channel
*c
);
303 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
305 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
307 static struct rdpkt1_state_tag
{
308 long len
, pad
, biglen
, to_read
;
309 unsigned long realcrc
, gotcrc
;
315 static struct rdpkt2_state_tag
{
316 long len
, pad
, payload
, packetlen
, maclen
;
319 unsigned long incoming_sequence
;
322 static int ssh_channelcmp(void *av
, void *bv
) {
323 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
324 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
325 if (a
->localid
< b
->localid
) return -1;
326 if (a
->localid
> b
->localid
) return +1;
329 static int ssh_channelfind(void *av
, void *bv
) {
330 unsigned *a
= (unsigned *)av
;
331 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
332 if (*a
< b
->localid
) return -1;
333 if (*a
> b
->localid
) return +1;
337 static void c_write (char *buf
, int len
) {
338 if ((flags
& FLAG_STDERR
)) {
340 for (i
= 0; i
< len
; i
++)
342 fputc(buf
[i
], stderr
);
345 from_backend(1, buf
, len
);
349 * Collect incoming data in the incoming packet buffer.
350 * Decipher and verify the packet when it is completely read.
351 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
352 * Update the *data and *datalen variables.
353 * Return the additional nr of bytes needed, or 0 when
354 * a complete packet is available.
356 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
358 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
367 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
368 while ((*datalen
) == 0)
370 st
->len
= (st
->len
<< 8) + **data
;
371 (*data
)++, (*datalen
)--;
375 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
376 st
->len
= 0x300; /* big enough to carry to end */
380 st
->pad
= 8 - (st
->len
% 8);
381 st
->biglen
= st
->len
+ st
->pad
;
382 pktin
.length
= st
->len
- 5;
384 if (pktin
.maxlen
< st
->biglen
) {
385 pktin
.maxlen
= st
->biglen
;
386 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
387 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
389 fatalbox("Out of memory");
392 st
->to_read
= st
->biglen
;
394 while (st
->to_read
> 0) {
395 st
->chunk
= st
->to_read
;
396 while ((*datalen
) == 0)
397 crReturn(st
->to_read
);
398 if (st
->chunk
> (*datalen
))
399 st
->chunk
= (*datalen
);
400 memcpy(st
->p
, *data
, st
->chunk
);
402 *datalen
-= st
->chunk
;
404 st
->to_read
-= st
->chunk
;
408 cipher
->decrypt(pktin
.data
, st
->biglen
);
410 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
411 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
412 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
416 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
417 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
418 if (st
->gotcrc
!= st
->realcrc
) {
419 bombout(("Incorrect CRC received on packet"));
423 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
425 if (ssh1_compressing
) {
426 unsigned char *decompblk
;
430 debug(("Packet payload pre-decompression:\n"));
431 for (i
= -1; i
< pktin
.length
; i
++)
432 debug((" %02x", (unsigned char)pktin
.body
[i
]));
435 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
436 &decompblk
, &decomplen
);
438 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
439 pktin
.maxlen
= st
->pad
+ decomplen
;
440 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
441 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
443 fatalbox("Out of memory");
446 memcpy(pktin
.body
-1, decompblk
, decomplen
);
448 pktin
.length
= decomplen
-1;
450 debug(("Packet payload post-decompression:\n"));
451 for (i
= -1; i
< pktin
.length
; i
++)
452 debug((" %02x", (unsigned char)pktin
.body
[i
]));
457 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
458 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
459 pktin
.type
== SSH1_MSG_DEBUG
||
460 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
461 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
462 long strlen
= GET_32BIT(pktin
.body
);
463 if (strlen
+ 4 != pktin
.length
) {
464 bombout(("Received data packet with bogus string length"));
469 pktin
.type
= pktin
.body
[-1];
471 if (pktin
.type
== SSH1_MSG_DEBUG
) {
472 /* log debug message */
474 int strlen
= GET_32BIT(pktin
.body
);
475 strcpy(buf
, "Remote: ");
476 if (strlen
> 70) strlen
= 70;
477 memcpy(buf
+8, pktin
.body
+4, strlen
);
478 buf
[8+strlen
] = '\0';
481 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
489 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
491 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
499 st
->cipherblk
= sccipher
->blksize
;
502 if (st
->cipherblk
< 8)
505 if (pktin
.maxlen
< st
->cipherblk
) {
506 pktin
.maxlen
= st
->cipherblk
;
507 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
508 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
510 fatalbox("Out of memory");
514 * Acquire and decrypt the first block of the packet. This will
515 * contain the length and padding details.
517 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
518 while ((*datalen
) == 0)
519 crReturn(st
->cipherblk
-st
->i
);
520 pktin
.data
[st
->i
] = *(*data
)++;
524 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
529 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
532 * Now get the length and padding figures.
534 st
->len
= GET_32BIT(pktin
.data
);
535 st
->pad
= pktin
.data
[4];
538 * This enables us to deduce the payload length.
540 st
->payload
= st
->len
- st
->pad
- 1;
542 pktin
.length
= st
->payload
+ 5;
545 * So now we can work out the total packet length.
547 st
->packetlen
= st
->len
+ 4;
548 st
->maclen
= scmac ? scmac
->len
: 0;
551 * Adjust memory allocation if packet is too big.
553 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
554 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
555 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
556 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
558 fatalbox("Out of memory");
562 * Read and decrypt the remainder of the packet.
564 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
565 while ((*datalen
) == 0)
566 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
567 pktin
.data
[st
->i
] = *(*data
)++;
570 /* Decrypt everything _except_ the MAC. */
572 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
573 st
->packetlen
- st
->cipherblk
);
576 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
577 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
578 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
585 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
586 bombout(("Incorrect MAC received on packet"));
589 st
->incoming_sequence
++; /* whether or not we MACed */
592 * Decompress packet payload.
595 unsigned char *newpayload
;
597 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
598 &newpayload
, &newlen
)) {
599 if (pktin
.maxlen
< newlen
+5) {
600 pktin
.maxlen
= newlen
+5;
601 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
602 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
604 fatalbox("Out of memory");
606 pktin
.length
= 5 + newlen
;
607 memcpy(pktin
.data
+5, newpayload
, newlen
);
609 debug(("Post-decompression payload:\r\n"));
610 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
611 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
620 pktin
.type
= pktin
.data
[5];
622 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
623 goto next_packet
; /* FIXME: print DEBUG message */
628 static void ssh1_pktout_size(int len
) {
631 len
+= 5; /* type and CRC */
635 pktout
.length
= len
-5;
636 if (pktout
.maxlen
< biglen
) {
637 pktout
.maxlen
= biglen
;
639 /* Allocate enough buffer space for extra block
640 * for MS CryptEncrypt() */
641 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
642 srealloc(pktout
.data
, biglen
+12));
644 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
645 srealloc(pktout
.data
, biglen
+4));
648 fatalbox("Out of memory");
650 pktout
.body
= pktout
.data
+4+pad
+1;
653 static void s_wrpkt_start(int type
, int len
) {
654 ssh1_pktout_size(len
);
658 static void s_wrpkt(void) {
659 int pad
, len
, biglen
, i
;
662 pktout
.body
[-1] = pktout
.type
;
664 if (ssh1_compressing
) {
665 unsigned char *compblk
;
668 debug(("Packet payload pre-compression:\n"));
669 for (i
= -1; i
< pktout
.length
; i
++)
670 debug((" %02x", (unsigned char)pktout
.body
[i
]));
673 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
675 ssh1_pktout_size(complen
-1);
676 memcpy(pktout
.body
-1, compblk
, complen
);
679 debug(("Packet payload post-compression:\n"));
680 for (i
= -1; i
< pktout
.length
; i
++)
681 debug((" %02x", (unsigned char)pktout
.body
[i
]));
686 len
= pktout
.length
+ 5; /* type and CRC */
690 for (i
=0; i
<pad
; i
++)
691 pktout
.data
[i
+4] = random_byte();
692 crc
= crc32(pktout
.data
+4, biglen
-4);
693 PUT_32BIT(pktout
.data
+biglen
, crc
);
694 PUT_32BIT(pktout
.data
, len
);
697 debug(("Sending packet len=%d\r\n", biglen
+4));
698 for (i
= 0; i
< biglen
+4; i
++)
699 debug((" %02x", (unsigned char)pktout
.data
[i
]));
703 cipher
->encrypt(pktout
.data
+4, biglen
);
705 sk_write(s
, pktout
.data
, biglen
+4);
709 * Construct a packet with the specified contents and
710 * send it to the server.
712 static void send_packet(int pkttype
, ...)
715 unsigned char *p
, *argp
, argchar
;
716 unsigned long argint
;
717 int pktlen
, argtype
, arglen
;
721 va_start(args
, pkttype
);
722 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
725 (void) va_arg(args
, int);
729 (void) va_arg(args
, char);
733 (void) va_arg(args
, unsigned char *);
734 arglen
= va_arg(args
, int);
738 argp
= va_arg(args
, unsigned char *);
739 arglen
= strlen(argp
);
740 pktlen
+= 4 + arglen
;
743 bn
= va_arg(args
, Bignum
);
744 pktlen
+= ssh1_bignum_length(bn
);
752 s_wrpkt_start(pkttype
, pktlen
);
755 va_start(args
, pkttype
);
756 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
759 argint
= va_arg(args
, int);
760 PUT_32BIT(p
, argint
);
764 argchar
= va_arg(args
, unsigned char);
769 argp
= va_arg(args
, unsigned char *);
770 arglen
= va_arg(args
, int);
771 memcpy(p
, argp
, arglen
);
775 argp
= va_arg(args
, unsigned char *);
776 arglen
= strlen(argp
);
777 PUT_32BIT(p
, arglen
);
778 memcpy(p
+ 4, argp
, arglen
);
782 bn
= va_arg(args
, Bignum
);
783 p
+= ssh1_write_bignum(p
, bn
);
792 static int ssh_versioncmp(char *a
, char *b
) {
794 unsigned long av
, bv
;
796 av
= strtoul(a
, &ae
, 10);
797 bv
= strtoul(b
, &be
, 10);
798 if (av
!= bv
) return (av
< bv ?
-1 : +1);
799 if (*ae
== '.') ae
++;
800 if (*be
== '.') be
++;
801 av
= strtoul(ae
, &ae
, 10);
802 bv
= strtoul(be
, &be
, 10);
803 if (av
!= bv
) return (av
< bv ?
-1 : +1);
809 * Utility routine for putting an SSH-protocol `string' into a SHA
813 static void sha_string(SHA_State
*s
, void *str
, int len
) {
814 unsigned char lenblk
[4];
815 PUT_32BIT(lenblk
, len
);
816 SHA_Bytes(s
, lenblk
, 4);
817 SHA_Bytes(s
, str
, len
);
821 * SSH2 packet construction functions.
823 static void ssh2_pkt_ensure(int length
) {
824 if (pktout
.maxlen
< length
) {
825 pktout
.maxlen
= length
+ 256;
826 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
827 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
829 fatalbox("Out of memory");
832 static void ssh2_pkt_adddata(void *data
, int len
) {
833 pktout
.length
+= len
;
834 ssh2_pkt_ensure(pktout
.length
);
835 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
837 static void ssh2_pkt_addbyte(unsigned char byte
) {
838 ssh2_pkt_adddata(&byte
, 1);
840 static void ssh2_pkt_init(int pkt_type
) {
842 ssh2_pkt_addbyte((unsigned char)pkt_type
);
844 static void ssh2_pkt_addbool(unsigned char value
) {
845 ssh2_pkt_adddata(&value
, 1);
847 static void ssh2_pkt_adduint32(unsigned long value
) {
850 ssh2_pkt_adddata(x
, 4);
852 static void ssh2_pkt_addstring_start(void) {
853 ssh2_pkt_adduint32(0);
854 pktout
.savedpos
= pktout
.length
;
856 static void ssh2_pkt_addstring_str(char *data
) {
857 ssh2_pkt_adddata(data
, strlen(data
));
858 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
859 pktout
.length
- pktout
.savedpos
);
861 static void ssh2_pkt_addstring_data(char *data
, int len
) {
862 ssh2_pkt_adddata(data
, len
);
863 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
864 pktout
.length
- pktout
.savedpos
);
866 static void ssh2_pkt_addstring(char *data
) {
867 ssh2_pkt_addstring_start();
868 ssh2_pkt_addstring_str(data
);
870 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
873 p
= smalloc(n
* 2 + 1);
875 fatalbox("out of memory");
877 for (i
= 0; i
< n
; i
++) {
878 p
[i
*2+1] = (b
[n
-i
] >> 8) & 0xFF;
879 p
[i
*2+2] = (b
[n
-i
] ) & 0xFF;
882 while (p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
884 memmove(p
, p
+i
, n
*2+1-i
);
888 static void ssh2_pkt_addmp(Bignum b
) {
891 p
= ssh2_mpint_fmt(b
, &len
);
892 ssh2_pkt_addstring_start();
893 ssh2_pkt_addstring_data(p
, len
);
898 * Construct an SSH2 final-form packet: compress it, encrypt it,
899 * put the MAC on it. Final packet, ready to be sent, is stored in
900 * pktout.data. Total length is returned.
902 static int ssh2_pkt_construct(void) {
903 int cipherblk
, maclen
, padding
, i
;
904 static unsigned long outgoing_sequence
= 0;
907 * Compress packet payload.
910 debug(("Pre-compression payload:\r\n"));
911 for (i
= 5; i
< pktout
.length
; i
++)
912 debug((" %02x", (unsigned char)pktout
.data
[i
]));
916 unsigned char *newpayload
;
918 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
919 &newpayload
, &newlen
)) {
921 ssh2_pkt_adddata(newpayload
, newlen
);
927 * Add padding. At least four bytes, and must also bring total
928 * length (minus MAC) up to a multiple of the block size.
930 cipherblk
= cipher ? cipher
->blksize
: 8; /* block size */
931 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
933 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
934 maclen
= csmac ? csmac
->len
: 0;
935 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
936 pktout
.data
[4] = padding
;
937 for (i
= 0; i
< padding
; i
++)
938 pktout
.data
[pktout
.length
+ i
] = random_byte();
939 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
941 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
943 outgoing_sequence
++; /* whether or not we MACed */
946 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
947 for (i
= 0; i
< pktout
.length
+padding
; i
++)
948 debug((" %02x", (unsigned char)pktout
.data
[i
]));
953 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
955 /* Ready-to-send packet starts at pktout.data. We return length. */
956 return pktout
.length
+ padding
+ maclen
;
960 * Construct and send an SSH2 packet immediately.
962 static void ssh2_pkt_send(void) {
963 int len
= ssh2_pkt_construct();
964 sk_write(s
, pktout
.data
, len
);
968 * Construct an SSH2 packet and add it to a deferred data block.
969 * Useful for sending multiple packets in a single sk_write() call,
970 * to prevent a traffic-analysing listener from being able to work
971 * out the length of any particular packet (such as the password
974 * Note that because SSH2 sequence-numbers its packets, this can
975 * NOT be used as an m4-style `defer' allowing packets to be
976 * constructed in one order and sent in another.
978 static void ssh2_pkt_defer(void) {
979 int len
= ssh2_pkt_construct();
980 if (deferred_len
+ len
> deferred_size
) {
981 deferred_size
= deferred_len
+ len
+ 128;
982 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
984 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
989 * Send the whole deferred data block constructed by
992 static void ssh2_pkt_defersend(void) {
993 sk_write(s
, deferred_send_data
, deferred_len
);
994 deferred_len
= deferred_size
= 0;
995 sfree(deferred_send_data
);
996 deferred_send_data
= NULL
;
1000 void bndebug(char *string
, Bignum b
) {
1003 p
= ssh2_mpint_fmt(b
, &len
);
1004 debug(("%s", string
));
1005 for (i
= 0; i
< len
; i
++)
1006 debug((" %02x", p
[i
]));
1012 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1015 p
= ssh2_mpint_fmt(b
, &len
);
1016 sha_string(s
, p
, len
);
1021 * SSH2 packet decode functions.
1023 static unsigned long ssh2_pkt_getuint32(void) {
1024 unsigned long value
;
1025 if (pktin
.length
- pktin
.savedpos
< 4)
1026 return 0; /* arrgh, no way to decline (FIXME?) */
1027 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1028 pktin
.savedpos
+= 4;
1031 static void ssh2_pkt_getstring(char **p
, int *length
) {
1033 if (pktin
.length
- pktin
.savedpos
< 4)
1035 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1036 pktin
.savedpos
+= 4;
1037 if (pktin
.length
- pktin
.savedpos
< *length
)
1039 *p
= pktin
.data
+pktin
.savedpos
;
1040 pktin
.savedpos
+= *length
;
1042 static Bignum
ssh2_pkt_getmp(void) {
1047 ssh2_pkt_getstring(&p
, &length
);
1051 bombout(("internal error: Can't handle negative mpints"));
1054 b
= newbn((length
+1)/2);
1055 for (i
= 0; i
< length
; i
++) {
1058 b
[j
/2+1] |= ((unsigned char)p
[i
]) << 8;
1060 b
[j
/2+1] |= ((unsigned char)p
[i
]);
1062 while (b
[0] > 1 && b
[b
[0]] == 0) b
[0]--;
1066 static int do_ssh_init(unsigned char c
) {
1068 static char version
[10];
1069 static char vstring
[80];
1070 static char vlog
[sizeof(vstring
)+20];
1075 /* Search for the string "SSH-" in the input. */
1078 static const int transS
[] = { 1, 2, 2, 1 };
1079 static const int transH
[] = { 0, 0, 3, 0 };
1080 static const int transminus
[] = { 0, 0, 0, -1 };
1081 if (c
== 'S') i
= transS
[i
];
1082 else if (c
== 'H') i
= transH
[i
];
1083 else if (c
== '-') i
= transminus
[i
];
1087 crReturn(1); /* get another character */
1090 strcpy(vstring
, "SSH-");
1094 crReturn(1); /* get another char */
1095 if (vsp
< vstring
+sizeof(vstring
)-1)
1101 } else if (i
< sizeof(version
)-1)
1108 ssh_agentfwd_enabled
= FALSE
;
1109 rdpkt2_state
.incoming_sequence
= 0;
1112 sprintf(vlog
, "Server version: %s", vstring
);
1113 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1117 * Server version "1.99" means we can choose whether we use v1
1118 * or v2 protocol. Choice is based on cfg.sshprot.
1120 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1122 * This is a v2 server. Begin v2 protocol.
1124 char *verstring
= "SSH-2.0-PuTTY";
1125 SHA_Init(&exhashbase
);
1127 * Hash our version string and their version string.
1129 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1130 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1131 sprintf(vstring
, "%s\n", verstring
);
1132 sprintf(vlog
, "We claim version: %s", verstring
);
1134 logevent("Using SSH protocol version 2");
1135 sk_write(s
, vstring
, strlen(vstring
));
1136 ssh_protocol
= ssh2_protocol
;
1138 s_rdpkt
= ssh2_rdpkt
;
1141 * This is a v1 server. Begin v1 protocol.
1143 sprintf(vstring
, "SSH-%s-PuTTY\n",
1144 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1145 sprintf(vlog
, "We claim version: %s", vstring
);
1146 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1148 logevent("Using SSH protocol version 1");
1149 sk_write(s
, vstring
, strlen(vstring
));
1150 ssh_protocol
= ssh1_protocol
;
1152 s_rdpkt
= ssh1_rdpkt
;
1154 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1159 static void ssh_gotdata(unsigned char *data
, int datalen
)
1164 * To begin with, feed the characters one by one to the
1165 * protocol initialisation / selection function do_ssh_init().
1166 * When that returns 0, we're done with the initial greeting
1167 * exchange and can move on to packet discipline.
1172 crReturnV
; /* more data please */
1173 ret
= do_ssh_init(*data
);
1180 * We emerge from that loop when the initial negotiation is
1181 * over and we have selected an s_rdpkt function. Now pass
1182 * everything to s_rdpkt, and then pass the resulting packets
1183 * to the proper protocol handler.
1188 while (datalen
> 0) {
1189 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1190 ssh_protocol(NULL
, 0, 1);
1191 if (ssh_state
== SSH_STATE_CLOSED
) {
1201 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1203 /* A socket error has occurred. */
1204 ssh_state
= SSH_STATE_CLOSED
;
1207 connection_fatal(data
);
1210 /* Connection has closed. */
1211 ssh_state
= SSH_STATE_CLOSED
;
1216 ssh_gotdata (data
, len
);
1217 if (ssh_state
== SSH_STATE_CLOSED
) {
1228 * Connect to specified host and port.
1229 * Returns an error message, or NULL on success.
1230 * Also places the canonical host name into `realhost'.
1232 static char *connect_to_host(char *host
, int port
, char **realhost
)
1241 savedhost
= smalloc(1+strlen(host
));
1243 fatalbox("Out of memory");
1244 strcpy(savedhost
, host
);
1247 port
= 22; /* default ssh port */
1260 addr
= sk_namelookup(host
, realhost
);
1261 if ( (err
= sk_addr_error(addr
)) )
1271 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1272 if ( (err
= sk_socket_error(s
)) )
1276 sk_write(s
, "connect ", 8);
1277 sk_write(s
, FWhost
, strlen(FWhost
));
1280 sprintf(buf
, " %d\n", FWport
);
1281 sk_write(s
, buf
, strlen(buf
));
1289 * Handle the key exchange and user authentication phases.
1291 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1294 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1295 unsigned char cookie
[8];
1296 struct RSAKey servkey
, hostkey
;
1297 struct MD5Context md5c
;
1298 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1299 static int tried_publickey
;
1300 static unsigned char session_id
[16];
1302 static char username
[100];
1306 if (!ispkt
) crWaitUntil(ispkt
);
1308 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1309 bombout(("Public key packet not received"));
1313 logevent("Received public keys");
1315 memcpy(cookie
, pktin
.body
, 8);
1317 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1318 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1321 * Log the host key fingerprint.
1325 logevent("Host key fingerprint is:");
1326 strcpy(logmsg
, " ");
1327 hostkey
.comment
= NULL
;
1328 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1333 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1334 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1337 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1338 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1339 MD5Update(&md5c
, pktin
.body
, 8);
1340 MD5Final(session_id
, &md5c
);
1342 for (i
=0; i
<32; i
++)
1343 session_key
[i
] = random_byte();
1345 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1347 rsabuf
= smalloc(len
);
1349 fatalbox("Out of memory");
1352 * Verify the host key.
1356 * First format the key into a string.
1358 int len
= rsastr_len(&hostkey
);
1359 char fingerprint
[100];
1360 char *keystr
= smalloc(len
);
1362 fatalbox("Out of memory");
1363 rsastr_fmt(keystr
, &hostkey
);
1364 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1365 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1369 for (i
=0; i
<32; i
++) {
1370 rsabuf
[i
] = session_key
[i
];
1372 rsabuf
[i
] ^= session_id
[i
];
1375 if (hostkey
.bytes
> servkey
.bytes
) {
1376 rsaencrypt(rsabuf
, 32, &servkey
);
1377 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1379 rsaencrypt(rsabuf
, 32, &hostkey
);
1380 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1383 logevent("Encrypted session key");
1385 cipher_type
= cfg
.cipher
== CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH
:
1386 cfg
.cipher
== CIPHER_DES ? SSH_CIPHER_DES
:
1388 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1389 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1390 cipher_type
= SSH_CIPHER_3DES
;
1392 switch (cipher_type
) {
1393 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1394 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1395 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1398 send_packet(SSH1_CMSG_SESSION_KEY
,
1399 PKT_CHAR
, cipher_type
,
1400 PKT_DATA
, cookie
, 8,
1401 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1402 PKT_DATA
, rsabuf
, len
,
1406 logevent("Trying to enable encryption...");
1410 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1411 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1413 cipher
->sesskey(session_key
);
1417 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1418 bombout(("Encryption not successfully enabled"));
1422 logevent("Successfully started encryption");
1428 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1429 c_write("login as: ", 10);
1432 crWaitUntil(!ispkt
);
1433 while (inlen
--) switch (c
= *in
++) {
1440 c_write("\b \b", 3);
1446 c_write("\b \b", 3);
1455 if (((c
>= ' ' && c
<= '~') ||
1456 ((unsigned char)c
>= 160)) && pos
< 40) {
1457 username
[pos
++] = c
;
1464 username
[strcspn(username
, "\n\r")] = '\0';
1466 strncpy(username
, cfg
.username
, 99);
1467 username
[99] = '\0';
1470 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1472 char userlog
[22+sizeof(username
)];
1473 sprintf(userlog
, "Sent username \"%s\"", username
);
1475 if (flags
& FLAG_INTERACTIVE
&&
1476 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1477 strcat(userlog
, "\r\n");
1478 c_write(userlog
, strlen(userlog
));
1485 tried_publickey
= 0;
1487 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1488 static char password
[100];
1489 static char prompt
[200];
1492 static int pwpkt_type
;
1494 * Show password prompt, having first obtained it via a TIS
1495 * or CryptoCard exchange if we're doing TIS or CryptoCard
1498 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1499 if (agent_exists()) {
1501 * Attempt RSA authentication using Pageant.
1503 static unsigned char request
[5], *response
, *p
;
1504 static int responselen
;
1505 static int i
, nkeys
;
1506 static int authed
= FALSE
;
1509 logevent("Pageant is running. Requesting keys.");
1511 /* Request the keys held by the agent. */
1512 PUT_32BIT(request
, 1);
1513 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1514 agent_query(request
, 5, &r
, &responselen
);
1515 response
= (unsigned char *)r
;
1518 nkeys
= GET_32BIT(p
); p
+= 4;
1519 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1521 for (i
= 0; i
< nkeys
; i
++) {
1522 static struct RSAKey key
;
1523 static Bignum challenge
;
1524 static char *commentp
;
1525 static int commentlen
;
1527 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1530 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1531 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1532 commentlen
= GET_32BIT(p
); p
+= 4;
1533 commentp
= p
; p
+= commentlen
;
1534 send_packet(SSH1_CMSG_AUTH_RSA
,
1535 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1537 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1538 logevent("Key refused");
1541 logevent("Received RSA challenge");
1542 ssh1_read_bignum(pktin
.body
, &challenge
);
1544 char *agentreq
, *q
, *ret
;
1546 len
= 1 + 4; /* message type, bit count */
1547 len
+= ssh1_bignum_length(key
.exponent
);
1548 len
+= ssh1_bignum_length(key
.modulus
);
1549 len
+= ssh1_bignum_length(challenge
);
1550 len
+= 16; /* session id */
1551 len
+= 4; /* response format */
1552 agentreq
= smalloc(4 + len
);
1553 PUT_32BIT(agentreq
, len
);
1555 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1556 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1558 q
+= ssh1_write_bignum(q
, key
.exponent
);
1559 q
+= ssh1_write_bignum(q
, key
.modulus
);
1560 q
+= ssh1_write_bignum(q
, challenge
);
1561 memcpy(q
, session_id
, 16); q
+= 16;
1562 PUT_32BIT(q
, 1); /* response format */
1563 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1566 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1567 logevent("Sending Pageant's response");
1568 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1569 PKT_DATA
, ret
+5, 16, PKT_END
);
1572 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1573 logevent("Pageant's response accepted");
1574 if (flags
& FLAG_VERBOSE
) {
1575 c_write("Authenticated using RSA key \"",
1577 c_write(commentp
, commentlen
);
1578 c_write("\" from agent\r\n", 14);
1582 logevent("Pageant's response not accepted");
1584 logevent("Pageant failed to answer challenge");
1588 logevent("No reply received from Pageant");
1591 freebn(key
.exponent
);
1592 freebn(key
.modulus
);
1601 if (*cfg
.keyfile
&& !tried_publickey
)
1602 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1604 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1606 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1607 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1608 logevent("Requested TIS authentication");
1609 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1611 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1612 logevent("TIS authentication declined");
1613 if (flags
& FLAG_INTERACTIVE
)
1614 c_write("TIS authentication refused.\r\n", 29);
1616 int challengelen
= ((pktin
.body
[0] << 24) |
1617 (pktin
.body
[1] << 16) |
1618 (pktin
.body
[2] << 8) |
1620 logevent("Received TIS challenge");
1621 if (challengelen
> sizeof(prompt
)-1)
1622 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1623 memcpy(prompt
, pktin
.body
+4, challengelen
);
1624 prompt
[challengelen
] = '\0';
1627 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1629 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1630 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1631 logevent("Requested CryptoCard authentication");
1632 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1634 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1635 logevent("CryptoCard authentication declined");
1636 c_write("CryptoCard authentication refused.\r\n", 29);
1638 int challengelen
= ((pktin
.body
[0] << 24) |
1639 (pktin
.body
[1] << 16) |
1640 (pktin
.body
[2] << 8) |
1642 logevent("Received CryptoCard challenge");
1643 if (challengelen
> sizeof(prompt
)-1)
1644 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1645 memcpy(prompt
, pktin
.body
+4, challengelen
);
1646 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1647 sizeof(prompt
)-challengelen
);
1648 prompt
[sizeof(prompt
)-1] = '\0';
1651 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1652 sprintf(prompt
, "%.90s@%.90s's password: ",
1653 username
, savedhost
);
1655 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1656 char *comment
= NULL
;
1657 if (flags
& FLAG_VERBOSE
)
1658 c_write("Trying public key authentication.\r\n", 35);
1659 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1660 if (flags
& FLAG_VERBOSE
)
1661 c_write("No passphrase required.\r\n", 25);
1664 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1668 if (ssh_get_password
) {
1669 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1671 * get_password failed to get a password (for
1672 * example because one was supplied on the command
1673 * line which has already failed to work).
1676 logevent("No more passwords to try");
1677 ssh_state
= SSH_STATE_CLOSED
;
1681 c_write(prompt
, strlen(prompt
));
1685 crWaitUntil(!ispkt
);
1686 while (inlen
--) switch (c
= *in
++) {
1703 if (((c
>= ' ' && c
<= '~') ||
1704 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1705 password
[pos
++] = c
;
1713 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1715 * Try public key authentication with the specified
1718 static struct RSAKey pubkey
;
1719 static Bignum challenge
, response
;
1721 static unsigned char buffer
[32];
1723 tried_publickey
= 1;
1724 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1726 c_write("Couldn't load public key from ", 30);
1727 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1728 c_write(".\r\n", 3);
1729 continue; /* go and try password */
1732 c_write("Wrong passphrase.\r\n", 19);
1733 tried_publickey
= 0;
1734 continue; /* try again */
1738 * Send a public key attempt.
1740 send_packet(SSH1_CMSG_AUTH_RSA
,
1741 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1744 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1745 c_write("Server refused our public key.\r\n", 32);
1746 continue; /* go and try password */
1748 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1749 bombout(("Bizarre response to offer of public key"));
1752 ssh1_read_bignum(pktin
.body
, &challenge
);
1753 response
= rsadecrypt(challenge
, &pubkey
);
1754 freebn(pubkey
.private_exponent
); /* burn the evidence */
1756 for (i
= 0; i
< 32; i
+= 2) {
1757 buffer
[i
] = response
[16-i
/2] >> 8;
1758 buffer
[i
+1] = response
[16-i
/2] & 0xFF;
1762 MD5Update(&md5c
, buffer
, 32);
1763 MD5Update(&md5c
, session_id
, 16);
1764 MD5Final(buffer
, &md5c
);
1766 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1767 PKT_DATA
, buffer
, 16, PKT_END
);
1770 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1771 if (flags
& FLAG_VERBOSE
)
1772 c_write("Failed to authenticate with our public key.\r\n",
1774 continue; /* go and try password */
1775 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1776 bombout(("Bizarre response to RSA authentication response"));
1780 break; /* we're through! */
1782 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1784 logevent("Sent password");
1785 memset(password
, 0, strlen(password
));
1787 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1788 if (flags
& FLAG_VERBOSE
)
1789 c_write("Access denied\r\n", 15);
1790 logevent("Authentication refused");
1791 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1792 logevent("Received disconnect request");
1793 ssh_state
= SSH_STATE_CLOSED
;
1795 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1796 bombout(("Strange packet received, type %d", pktin
.type
));
1801 logevent("Authentication successful");
1806 void sshfwd_close(struct ssh_channel
*c
) {
1808 if (ssh_version
== 1) {
1809 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1811 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1812 ssh2_pkt_adduint32(c
->remoteid
);
1816 if (c
->type
== CHAN_X11
) {
1818 logevent("X11 connection terminated");
1823 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1824 if (ssh_version
== 1) {
1825 send_packet(SSH1_MSG_CHANNEL_DATA
,
1826 PKT_INT
, c
->remoteid
,
1831 ssh2_add_channel_data(c
, buf
, len
);
1836 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1841 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1844 if (ssh_state
== SSH_STATE_CLOSED
)
1847 if (cfg
.agentfwd
&& agent_exists()) {
1848 logevent("Requesting agent forwarding");
1849 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1850 do { crReturnV
; } while (!ispkt
);
1851 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1852 bombout(("Protocol confusion"));
1854 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1855 logevent("Agent forwarding refused");
1857 logevent("Agent forwarding enabled");
1858 ssh_agentfwd_enabled
= TRUE
;
1862 if (cfg
.x11_forward
) {
1863 char proto
[20], data
[64];
1864 logevent("Requesting X11 forwarding");
1865 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1866 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1867 PKT_STR
, proto
, PKT_STR
, data
,
1870 do { crReturnV
; } while (!ispkt
);
1871 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1872 bombout(("Protocol confusion"));
1874 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1875 logevent("X11 forwarding refused");
1877 logevent("X11 forwarding enabled");
1878 ssh_X11_fwd_enabled
= TRUE
;
1883 send_packet(SSH1_CMSG_REQUEST_PTY
,
1884 PKT_STR
, cfg
.termtype
,
1885 PKT_INT
, rows
, PKT_INT
, cols
,
1886 PKT_INT
, 0, PKT_INT
, 0,
1889 ssh_state
= SSH_STATE_INTERMED
;
1890 do { crReturnV
; } while (!ispkt
);
1891 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1892 bombout(("Protocol confusion"));
1894 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1895 c_write("Server refused to allocate pty\r\n", 32);
1896 ssh_editing
= ssh_echoing
= 1;
1898 logevent("Allocated pty");
1900 ssh_editing
= ssh_echoing
= 1;
1903 if (cfg
.compression
) {
1904 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1905 do { crReturnV
; } while (!ispkt
);
1906 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1907 bombout(("Protocol confusion"));
1909 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1910 c_write("Server refused to compress\r\n", 32);
1912 logevent("Started compression");
1913 ssh1_compressing
= TRUE
;
1914 zlib_compress_init();
1915 zlib_decompress_init();
1918 if (*cfg
.remote_cmd
)
1919 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1921 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1922 logevent("Started session");
1924 ssh_state
= SSH_STATE_SESSION
;
1928 ssh_special(TS_EOF
);
1930 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
1932 ssh_channels
= newtree234(ssh_channelcmp
);
1936 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1937 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1938 long len
= GET_32BIT(pktin
.body
);
1939 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
1941 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1942 ssh_state
= SSH_STATE_CLOSED
;
1943 logevent("Received disconnect request");
1945 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
1946 /* Remote side is trying to open a channel to talk to our
1947 * X-Server. Give them back a local channel number. */
1949 struct ssh_channel
*c
, *d
;
1952 logevent("Received X11 connect request");
1953 /* Refuse if X11 forwarding is disabled. */
1954 if (!ssh_X11_fwd_enabled
) {
1955 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1956 PKT_INT
, GET_32BIT(pktin
.body
),
1958 logevent("Rejected X11 connect request");
1960 c
= smalloc(sizeof(struct ssh_channel
));
1962 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
1963 logevent("opening X11 forward connection failed");
1965 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1966 PKT_INT
, GET_32BIT(pktin
.body
),
1969 logevent("opening X11 forward connection succeeded");
1970 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
1972 break; /* found a free number */
1975 c
->remoteid
= GET_32BIT(pktin
.body
);
1978 c
->type
= CHAN_X11
; /* identify channel type */
1979 add234(ssh_channels
, c
);
1980 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1981 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1983 logevent("Opened X11 forward channel");
1986 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
1987 /* Remote side is trying to open a channel to talk to our
1988 * agent. Give them back a local channel number. */
1990 struct ssh_channel
*c
;
1993 /* Refuse if agent forwarding is disabled. */
1994 if (!ssh_agentfwd_enabled
) {
1995 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1996 PKT_INT
, GET_32BIT(pktin
.body
),
2000 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
2002 break; /* found a free number */
2005 c
= smalloc(sizeof(struct ssh_channel
));
2006 c
->remoteid
= GET_32BIT(pktin
.body
);
2009 c
->type
= CHAN_AGENT
; /* identify channel type */
2010 c
->u
.a
.lensofar
= 0;
2011 add234(ssh_channels
, c
);
2012 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2013 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2016 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2017 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2018 /* Remote side closes a channel. */
2019 unsigned i
= GET_32BIT(pktin
.body
);
2020 struct ssh_channel
*c
;
2021 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2024 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2025 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2026 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2027 logevent("X11 connection closed");
2028 assert(c
->u
.x11
.s
!= NULL
);
2029 x11_close(c
->u
.x11
.s
);
2032 c
->closes
|= closetype
;
2033 if (c
->closes
== 3) {
2034 del234(ssh_channels
, c
);
2038 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2039 /* Data sent down one of our channels. */
2040 int i
= GET_32BIT(pktin
.body
);
2041 int len
= GET_32BIT(pktin
.body
+4);
2042 unsigned char *p
= pktin
.body
+8;
2043 struct ssh_channel
*c
;
2044 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2048 x11_send(c
->u
.x11
.s
, p
, len
);
2051 /* Data for an agent message. Buffer it. */
2053 if (c
->u
.a
.lensofar
< 4) {
2054 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2055 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2056 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2058 if (c
->u
.a
.lensofar
== 4) {
2059 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2060 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2061 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2063 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2064 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2065 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2066 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2068 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2069 void *reply
, *sentreply
;
2071 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2076 /* Fake SSH_AGENT_FAILURE. */
2077 sentreply
= "\0\0\0\1\5";
2080 send_packet(SSH1_MSG_CHANNEL_DATA
,
2081 PKT_INT
, c
->remoteid
,
2083 PKT_DATA
, sentreply
, replylen
,
2087 sfree(c
->u
.a
.message
);
2088 c
->u
.a
.lensofar
= 0;
2094 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2095 /* may be from EXEC_SHELL on some servers */
2096 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2097 /* may be from EXEC_SHELL on some servers
2098 * if no pty is available or in other odd cases. Ignore */
2099 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2100 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2102 bombout(("Strange packet received: type %d", pktin
.type
));
2107 int len
= min(inlen
, 512);
2108 send_packet(SSH1_CMSG_STDIN_DATA
,
2109 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2120 * Utility routine for decoding comma-separated strings in KEXINIT.
2122 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2123 int needlen
= strlen(needle
);
2126 * Is it at the start of the string?
2128 if (haylen
>= needlen
&& /* haystack is long enough */
2129 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2130 (haylen
== needlen
|| haystack
[needlen
] == ',')
2131 /* either , or EOS follows */
2135 * If not, search for the next comma and resume after that.
2136 * If no comma found, terminate.
2138 while (haylen
> 0 && *haystack
!= ',')
2139 haylen
--, haystack
++;
2142 haylen
--, haystack
++; /* skip over comma itself */
2147 * SSH2 key creation method.
2149 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2151 /* First 20 bytes. */
2154 SHA_Bytes(&s
, H
, 20);
2155 SHA_Bytes(&s
, &chr
, 1);
2156 SHA_Bytes(&s
, sessid
, 20);
2157 SHA_Final(&s
, keyspace
);
2158 /* Next 20 bytes. */
2161 SHA_Bytes(&s
, H
, 20);
2162 SHA_Bytes(&s
, keyspace
, 20);
2163 SHA_Final(&s
, keyspace
+20);
2167 * Handle the SSH2 transport layer.
2169 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2173 static Bignum e
, f
, K
;
2174 static const struct ssh_mac
**maclist
;
2176 static const struct ssh_cipher
*cscipher_tobe
= NULL
;
2177 static const struct ssh_cipher
*sccipher_tobe
= NULL
;
2178 static const struct ssh_mac
*csmac_tobe
= NULL
;
2179 static const struct ssh_mac
*scmac_tobe
= NULL
;
2180 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2181 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2182 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2183 static int hostkeylen
, siglen
;
2184 static void *hkey
; /* actual host key */
2185 static unsigned char exchange_hash
[20];
2186 static unsigned char first_exchange_hash
[20];
2187 static unsigned char keyspace
[40];
2188 static const struct ssh_cipher
*preferred_cipher
;
2189 static const struct ssh_compress
*preferred_comp
;
2190 static int first_kex
;
2197 * Set up the preferred cipher and compression.
2199 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2200 preferred_cipher
= &ssh_blowfish_ssh2
;
2201 } else if (cfg
.cipher
== CIPHER_DES
) {
2202 logevent("Single DES not supported in SSH2; using 3DES");
2203 preferred_cipher
= &ssh_3des_ssh2
;
2204 } else if (cfg
.cipher
== CIPHER_3DES
) {
2205 preferred_cipher
= &ssh_3des_ssh2
;
2207 /* Shouldn't happen, but we do want to initialise to _something_. */
2208 preferred_cipher
= &ssh_3des_ssh2
;
2210 if (cfg
.compression
)
2211 preferred_comp
= &ssh_zlib
;
2213 preferred_comp
= &ssh_comp_none
;
2216 * Be prepared to work around the buggy MAC problem.
2219 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2221 maclist
= macs
, nmacs
= lenof(macs
);
2225 * Construct and send our key exchange packet.
2227 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2228 for (i
= 0; i
< 16; i
++)
2229 ssh2_pkt_addbyte((unsigned char)random_byte());
2230 /* List key exchange algorithms. */
2231 ssh2_pkt_addstring_start();
2232 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2233 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2234 if (i
< lenof(kex_algs
)-1)
2235 ssh2_pkt_addstring_str(",");
2237 /* List server host key algorithms. */
2238 ssh2_pkt_addstring_start();
2239 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2240 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2241 if (i
< lenof(hostkey_algs
)-1)
2242 ssh2_pkt_addstring_str(",");
2244 /* List client->server encryption algorithms. */
2245 ssh2_pkt_addstring_start();
2246 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2247 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2248 ssh2_pkt_addstring_str(c
->name
);
2249 if (i
< lenof(ciphers
))
2250 ssh2_pkt_addstring_str(",");
2252 /* List server->client encryption algorithms. */
2253 ssh2_pkt_addstring_start();
2254 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2255 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2256 ssh2_pkt_addstring_str(c
->name
);
2257 if (i
< lenof(ciphers
))
2258 ssh2_pkt_addstring_str(",");
2260 /* List client->server MAC algorithms. */
2261 ssh2_pkt_addstring_start();
2262 for (i
= 0; i
< nmacs
; i
++) {
2263 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2265 ssh2_pkt_addstring_str(",");
2267 /* List server->client MAC algorithms. */
2268 ssh2_pkt_addstring_start();
2269 for (i
= 0; i
< nmacs
; i
++) {
2270 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2272 ssh2_pkt_addstring_str(",");
2274 /* List client->server compression algorithms. */
2275 ssh2_pkt_addstring_start();
2276 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2277 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2278 ssh2_pkt_addstring_str(c
->name
);
2279 if (i
< lenof(compressions
))
2280 ssh2_pkt_addstring_str(",");
2282 /* List server->client compression algorithms. */
2283 ssh2_pkt_addstring_start();
2284 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2285 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2286 ssh2_pkt_addstring_str(c
->name
);
2287 if (i
< lenof(compressions
))
2288 ssh2_pkt_addstring_str(",");
2290 /* List client->server languages. Empty list. */
2291 ssh2_pkt_addstring_start();
2292 /* List server->client languages. Empty list. */
2293 ssh2_pkt_addstring_start();
2294 /* First KEX packet does _not_ follow, because we're not that brave. */
2295 ssh2_pkt_addbool(FALSE
);
2297 ssh2_pkt_adduint32(0);
2299 exhash
= exhashbase
;
2300 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2304 if (!ispkt
) crWaitUntil(ispkt
);
2305 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2308 * Now examine the other side's KEXINIT to see what we're up
2311 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2312 bombout(("expected key exchange packet from server"));
2315 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2316 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2317 pktin
.savedpos
+= 16; /* skip garbage cookie */
2318 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2319 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2320 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2325 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2326 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2327 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2328 hostkey
= hostkey_algs
[i
];
2332 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2333 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2334 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2335 if (in_commasep_string(c
->name
, str
, len
)) {
2340 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2341 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2342 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2343 if (in_commasep_string(c
->name
, str
, len
)) {
2348 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2349 for (i
= 0; i
< nmacs
; i
++) {
2350 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2351 csmac_tobe
= maclist
[i
];
2355 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2356 for (i
= 0; i
< nmacs
; i
++) {
2357 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2358 scmac_tobe
= maclist
[i
];
2362 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2363 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2364 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2365 if (in_commasep_string(c
->name
, str
, len
)) {
2370 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2371 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2372 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2373 if (in_commasep_string(c
->name
, str
, len
)) {
2380 * Currently we only support Diffie-Hellman and DSS, so let's
2381 * bomb out if those aren't selected.
2383 if (kex
!= &ssh_diffiehellman
|| hostkey
!= &ssh_dss
) {
2384 bombout(("internal fault: chaos in SSH 2 transport layer"));
2389 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2392 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT
);
2397 if (pktin
.type
!= SSH2_MSG_KEXDH_REPLY
) {
2398 bombout(("expected key exchange packet from server"));
2401 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2402 f
= ssh2_pkt_getmp();
2403 ssh2_pkt_getstring(&sigdata
, &siglen
);
2407 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2408 sha_mpint(&exhash
, e
);
2409 sha_mpint(&exhash
, f
);
2410 sha_mpint(&exhash
, K
);
2411 SHA_Final(&exhash
, exchange_hash
);
2414 debug(("Exchange hash is:\r\n"));
2415 for (i
= 0; i
< 20; i
++)
2416 debug((" %02x", exchange_hash
[i
]));
2420 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2421 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2422 bombout(("Server failed host key check"));
2427 * Expect SSH2_MSG_NEWKEYS from server.
2430 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2431 bombout(("expected new-keys packet from server"));
2436 * Authenticate remote host: verify host key. (We've already
2437 * checked the signature of the exchange hash.)
2439 keystr
= hostkey
->fmtkey(hkey
);
2440 fingerprint
= hostkey
->fingerprint(hkey
);
2441 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2442 keystr
, fingerprint
);
2443 if (first_kex
) { /* don't bother logging this in rekeys */
2444 logevent("Host key fingerprint is:");
2445 logevent(fingerprint
);
2449 hostkey
->freekey(hkey
);
2452 * Send SSH2_MSG_NEWKEYS.
2454 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2458 * Create and initialise session keys.
2460 cscipher
= cscipher_tobe
;
2461 sccipher
= sccipher_tobe
;
2464 cscomp
= cscomp_tobe
;
2465 sccomp
= sccomp_tobe
;
2466 cscomp
->compress_init();
2467 sccomp
->decompress_init();
2469 * Set IVs after keys. Here we use the exchange hash from the
2470 * _first_ key exchange.
2473 memcpy(first_exchange_hash
, exchange_hash
, sizeof(exchange_hash
));
2474 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'C', keyspace
);
2475 cscipher
->setcskey(keyspace
);
2476 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'D', keyspace
);
2477 sccipher
->setsckey(keyspace
);
2478 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'A', keyspace
);
2479 cscipher
->setcsiv(keyspace
);
2480 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'B', keyspace
);
2481 sccipher
->setsciv(keyspace
);
2482 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'E', keyspace
);
2483 csmac
->setcskey(keyspace
);
2484 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'F', keyspace
);
2485 scmac
->setsckey(keyspace
);
2488 * If this is the first key exchange phase, we must pass the
2489 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2490 * wants to see it but because it will need time to initialise
2491 * itself before it sees an actual packet. In subsequent key
2492 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2493 * it would only confuse the layer above.
2501 * Now we're encrypting. Begin returning 1 to the protocol main
2502 * function so that other things can run on top of the
2503 * transport. If we ever see a KEXINIT, we must go back to the
2506 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2509 logevent("Server initiated key re-exchange");
2510 goto begin_key_exchange
;
2516 * Add data to an SSH2 channel output buffer.
2518 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2519 if (c
->v2
.outbufsize
<
2520 c
->v2
.outbuflen
+ len
) {
2522 c
->v2
.outbuflen
+ len
+ 1024;
2523 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2526 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2528 c
->v2
.outbuflen
+= len
;
2532 * Attempt to send data on an SSH2 channel.
2534 static void ssh2_try_send(struct ssh_channel
*c
) {
2535 while (c
->v2
.remwindow
> 0 &&
2536 c
->v2
.outbuflen
> 0) {
2537 unsigned len
= c
->v2
.remwindow
;
2538 if (len
> c
->v2
.outbuflen
)
2539 len
= c
->v2
.outbuflen
;
2540 if (len
> c
->v2
.remmaxpkt
)
2541 len
= c
->v2
.remmaxpkt
;
2542 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2543 ssh2_pkt_adduint32(c
->remoteid
);
2544 ssh2_pkt_addstring_start();
2545 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2547 c
->v2
.outbuflen
-= len
;
2548 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2550 c
->v2
.remwindow
-= len
;
2555 * Handle the SSH2 userauth and connection layers.
2557 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2559 static unsigned long remote_winsize
;
2560 static unsigned long remote_maxpkt
;
2565 * Request userauth protocol, and await a response to it.
2567 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2568 ssh2_pkt_addstring("ssh-userauth");
2570 crWaitUntilV(ispkt
);
2571 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2572 bombout(("Server refused user authentication protocol"));
2577 * FIXME: currently we support only password authentication.
2578 * (This places us technically in violation of the SSH2 spec.
2579 * We must fix this.)
2583 * Get a username and a password.
2585 static char username
[100];
2586 static char password
[100];
2590 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2591 c_write("login as: ", 10);
2594 crWaitUntilV(!ispkt
);
2595 while (inlen
--) switch (c
= *in
++) {
2602 c_write("\b \b", 3);
2608 c_write("\b \b", 3);
2617 if (((c
>= ' ' && c
<= '~') ||
2618 ((unsigned char)c
>= 160)) && pos
< 40) {
2619 username
[pos
++] = c
;
2626 username
[strcspn(username
, "\n\r")] = '\0';
2629 strncpy(username
, cfg
.username
, 99);
2630 username
[99] = '\0';
2631 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2632 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2633 c_write(stuff
, strlen(stuff
));
2637 if (ssh_get_password
) {
2639 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2640 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2642 * get_password failed to get a password (for
2643 * example because one was supplied on the command
2644 * line which has already failed to work).
2647 logevent("No more passwords to try");
2648 ssh_state
= SSH_STATE_CLOSED
;
2652 c_write("password: ", 10);
2657 crWaitUntilV(!ispkt
);
2658 while (inlen
--) switch (c
= *in
++) {
2675 if (((c
>= ' ' && c
<= '~') ||
2676 ((unsigned char)c
>= 160)) && pos
< 40)
2677 password
[pos
++] = c
;
2685 * We send the password packet lumped tightly together with
2686 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
2687 * string long enough to make the total length of the two
2688 * packets constant. This should ensure that a passive
2689 * listener doing traffic analyis can't work out the length
2692 * For this to work, we need an assumption about the
2693 * maximum length of the password packet. I think 256 is
2694 * pretty conservative. Anyone using a password longer than
2695 * that probably doesn't have much to worry about from
2696 * people who find out how long their password is!
2698 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2699 ssh2_pkt_addstring(username
);
2700 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2701 ssh2_pkt_addstring("password");
2702 ssh2_pkt_addbool(FALSE
);
2703 ssh2_pkt_addstring(password
);
2706 * We'll include a string that's an exact multiple of the
2707 * cipher block size. If the cipher is NULL for some
2708 * reason, we don't do this trick at all because we gain
2713 ssh2_pkt_init(SSH2_MSG_IGNORE
);
2714 ssh2_pkt_addstring_start();
2715 for (i
= deferred_len
; i
<= 256; i
+= cscipher
->blksize
) {
2716 for (j
= 0; j
< cscipher
->blksize
; j
++) {
2717 char c
= (char)random_byte();
2718 ssh2_pkt_addstring_data(&c
, 1);
2723 ssh2_pkt_defersend();
2725 crWaitUntilV(ispkt
);
2726 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2727 c_write("Access denied\r\n", 15);
2728 logevent("Authentication refused");
2734 * Now we're authenticated for the connection protocol. The
2735 * connection protocol will automatically have started at this
2736 * point; there's no need to send SERVICE_REQUEST.
2740 * So now create a channel with a session in it.
2742 mainchan
= smalloc(sizeof(struct ssh_channel
));
2743 mainchan
->localid
= 100; /* as good as any */
2744 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2745 ssh2_pkt_addstring("session");
2746 ssh2_pkt_adduint32(mainchan
->localid
);
2747 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2748 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2750 crWaitUntilV(ispkt
);
2751 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2752 bombout(("Server refused to open a session"));
2754 /* FIXME: error data comes back in FAILURE packet */
2756 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2757 bombout(("Server's channel confirmation cited wrong channel"));
2760 mainchan
->remoteid
= ssh2_pkt_getuint32();
2761 mainchan
->type
= CHAN_MAINSESSION
;
2762 mainchan
->closes
= 0;
2763 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
2764 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2765 mainchan
->v2
.outbuffer
= NULL
;
2766 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
2767 ssh_channels
= newtree234(ssh_channelcmp
);
2768 add234(ssh_channels
, mainchan
);
2769 logevent("Opened channel for session");
2772 * Potentially enable X11 forwarding.
2774 if (cfg
.x11_forward
) {
2775 char proto
[20], data
[64];
2776 logevent("Requesting X11 forwarding");
2777 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2778 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2779 ssh2_pkt_adduint32(mainchan
->remoteid
);
2780 ssh2_pkt_addstring("x11-req");
2781 ssh2_pkt_addbool(1); /* want reply */
2782 ssh2_pkt_addbool(0); /* many connections */
2783 ssh2_pkt_addstring(proto
);
2784 ssh2_pkt_addstring(data
);
2785 ssh2_pkt_adduint32(0); /* screen number */
2789 crWaitUntilV(ispkt
);
2790 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2791 unsigned i
= ssh2_pkt_getuint32();
2792 struct ssh_channel
*c
;
2793 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2795 continue; /* nonexistent channel */
2796 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2798 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2800 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2801 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2802 bombout(("Server got confused by X11 forwarding request"));
2805 logevent("X11 forwarding refused");
2807 logevent("X11 forwarding enabled");
2808 ssh_X11_fwd_enabled
= TRUE
;
2813 * Now allocate a pty for the session.
2816 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2817 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2818 ssh2_pkt_addstring("pty-req");
2819 ssh2_pkt_addbool(1); /* want reply */
2820 ssh2_pkt_addstring(cfg
.termtype
);
2821 ssh2_pkt_adduint32(cols
);
2822 ssh2_pkt_adduint32(rows
);
2823 ssh2_pkt_adduint32(0); /* pixel width */
2824 ssh2_pkt_adduint32(0); /* pixel height */
2825 ssh2_pkt_addstring_start();
2826 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2828 ssh_state
= SSH_STATE_INTERMED
;
2831 crWaitUntilV(ispkt
);
2832 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2833 unsigned i
= ssh2_pkt_getuint32();
2834 struct ssh_channel
*c
;
2835 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2837 continue; /* nonexistent channel */
2838 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2840 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2842 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2843 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2844 bombout(("Server got confused by pty request"));
2847 c_write("Server refused to allocate pty\r\n", 32);
2848 ssh_editing
= ssh_echoing
= 1;
2850 logevent("Allocated pty");
2853 ssh_editing
= ssh_echoing
= 1;
2857 * Start a shell or a remote command.
2859 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2860 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2861 if (cfg
.ssh_subsys
) {
2862 ssh2_pkt_addstring("subsystem");
2863 ssh2_pkt_addbool(1); /* want reply */
2864 ssh2_pkt_addstring(cfg
.remote_cmd
);
2865 } else if (*cfg
.remote_cmd
) {
2866 ssh2_pkt_addstring("exec");
2867 ssh2_pkt_addbool(1); /* want reply */
2868 ssh2_pkt_addstring(cfg
.remote_cmd
);
2870 ssh2_pkt_addstring("shell");
2871 ssh2_pkt_addbool(1); /* want reply */
2875 crWaitUntilV(ispkt
);
2876 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2877 unsigned i
= ssh2_pkt_getuint32();
2878 struct ssh_channel
*c
;
2879 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2881 continue; /* nonexistent channel */
2882 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2884 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2885 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2886 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2887 bombout(("Server got confused by shell/command request"));
2890 bombout(("Server refused to start a shell/command"));
2893 logevent("Started a shell/command");
2896 ssh_state
= SSH_STATE_SESSION
;
2900 ssh_special(TS_EOF
);
2905 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2908 static int try_send
;
2912 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2913 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2916 unsigned i
= ssh2_pkt_getuint32();
2917 struct ssh_channel
*c
;
2918 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2920 continue; /* nonexistent channel */
2921 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2922 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2923 continue; /* extended but not stderr */
2924 ssh2_pkt_getstring(&data
, &length
);
2927 case CHAN_MAINSESSION
:
2928 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
2932 x11_send(c
->u
.x11
.s
, data
, length
);
2936 * Enlarge the window again at the remote
2937 * side, just in case it ever runs down and
2938 * they fail to send us any more data.
2940 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2941 ssh2_pkt_adduint32(c
->remoteid
);
2942 ssh2_pkt_adduint32(length
);
2945 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
2946 ssh_state
= SSH_STATE_CLOSED
;
2947 logevent("Received disconnect message");
2949 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
2950 continue; /* exit status et al; ignore (FIXME?) */
2951 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
2952 unsigned i
= ssh2_pkt_getuint32();
2953 struct ssh_channel
*c
;
2955 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2957 continue; /* nonexistent channel */
2959 if (c
->type
== CHAN_X11
) {
2961 * Remote EOF on an X11 channel means we should
2962 * wrap up and close the channel ourselves.
2964 x11_close(c
->u
.x11
.s
);
2967 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
2968 unsigned i
= ssh2_pkt_getuint32();
2969 struct ssh_channel
*c
;
2972 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2974 continue; /* nonexistent channel */
2975 if (c
->closes
== 0) {
2976 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2977 ssh2_pkt_adduint32(c
->remoteid
);
2980 /* Do pre-close processing on the channel. */
2982 case CHAN_MAINSESSION
:
2983 break; /* nothing to see here, move along */
2987 del234(ssh_channels
, c
);
2988 sfree(c
->v2
.outbuffer
);
2992 * See if that was the last channel left open.
2994 c
= first234(ssh_channels
, &e
);
2996 logevent("All channels closed. Disconnecting");
2997 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
2998 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
2999 ssh2_pkt_addstring("All open channels closed");
3000 ssh2_pkt_addstring("en"); /* language tag */
3002 ssh_state
= SSH_STATE_CLOSED
;
3005 continue; /* remote sends close; ignore (FIXME) */
3006 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3007 unsigned i
= ssh2_pkt_getuint32();
3008 struct ssh_channel
*c
;
3009 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3011 continue; /* nonexistent channel */
3012 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3014 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3018 struct ssh_channel
*c
;
3019 ssh2_pkt_getstring(&type
, &typelen
);
3020 c
= smalloc(sizeof(struct ssh_channel
));
3022 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3023 if (!ssh_X11_fwd_enabled
)
3024 error
= "X11 forwarding is not enabled";
3025 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3026 error
= "Unable to open an X11 connection";
3031 error
= "Unsupported channel type requested";
3034 c
->remoteid
= ssh2_pkt_getuint32();
3036 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3037 ssh2_pkt_adduint32(c
->remoteid
);
3038 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3039 ssh2_pkt_addstring(error
);
3040 ssh2_pkt_addstring("en"); /* language tag */
3044 struct ssh_channel
*d
;
3048 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3051 break; /* found a free number */
3056 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3057 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3058 c
->v2
.outbuffer
= NULL
;
3059 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3060 add234(ssh_channels
, c
);
3061 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3062 ssh2_pkt_adduint32(c
->remoteid
);
3063 ssh2_pkt_adduint32(c
->localid
);
3064 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3065 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3069 bombout(("Strange packet received: type %d", pktin
.type
));
3074 * We have spare data. Add it to the channel buffer.
3076 ssh2_add_channel_data(mainchan
, in
, inlen
);
3081 struct ssh_channel
*c
;
3083 * Try to send data on all channels if we can.
3085 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3094 * Handle the top-level SSH2 protocol.
3096 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3098 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3100 do_ssh2_authconn(in
, inlen
, ispkt
);
3104 * Called to set up the connection.
3106 * Returns an error message, or NULL on success.
3108 static char *ssh_init (char *host
, int port
, char **realhost
) {
3112 if(crypto_startup() == 0)
3113 return "Microsoft high encryption pack not installed!";
3120 p
= connect_to_host(host
, port
, realhost
);
3128 * Called to send data down the Telnet connection.
3130 static void ssh_send (char *buf
, int len
) {
3131 if (s
== NULL
|| ssh_protocol
== NULL
)
3134 ssh_protocol(buf
, len
, 0);
3138 * Called to set the size of the window from SSH's POV.
3140 static void ssh_size(void) {
3141 switch (ssh_state
) {
3142 case SSH_STATE_BEFORE_SIZE
:
3143 case SSH_STATE_PREPACKET
:
3144 case SSH_STATE_CLOSED
:
3145 break; /* do nothing */
3146 case SSH_STATE_INTERMED
:
3147 size_needed
= TRUE
; /* buffer for later */
3149 case SSH_STATE_SESSION
:
3151 if (ssh_version
== 1) {
3152 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3153 PKT_INT
, rows
, PKT_INT
, cols
,
3154 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3156 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3157 ssh2_pkt_adduint32(mainchan
->remoteid
);
3158 ssh2_pkt_addstring("window-change");
3159 ssh2_pkt_addbool(0);
3160 ssh2_pkt_adduint32(cols
);
3161 ssh2_pkt_adduint32(rows
);
3162 ssh2_pkt_adduint32(0);
3163 ssh2_pkt_adduint32(0);
3172 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3173 * can send an EOF and collect resulting output (e.g. `plink
3176 static void ssh_special (Telnet_Special code
) {
3177 if (code
== TS_EOF
) {
3178 if (ssh_state
!= SSH_STATE_SESSION
) {
3180 * Buffer the EOF in case we are pre-SESSION, so we can
3181 * send it as soon as we reach SESSION.
3187 if (ssh_version
== 1) {
3188 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3190 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3191 ssh2_pkt_adduint32(mainchan
->remoteid
);
3194 logevent("Sent EOF message");
3195 } else if (code
== TS_PING
) {
3196 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3198 if (ssh_version
== 1) {
3199 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3201 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3202 ssh2_pkt_addstring_start();
3210 static Socket
ssh_socket(void) { return s
; }
3212 static int ssh_sendok(void) { return ssh_send_ok
; }
3214 static int ssh_ldisc(int option
) {
3215 if (option
== LD_ECHO
) return ssh_echoing
;
3216 if (option
== LD_EDIT
) return ssh_editing
;
3220 Backend ssh_backend
= {