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_blowfish_ssh1
;
171 extern const struct ssh_cipher ssh_blowfish_ssh2
;
173 extern char *x11_init (Socket
*, char *, void *);
174 extern void x11_close (Socket
);
175 extern void x11_send (Socket
, char *, int);
176 extern void x11_invent_auth(char *, int, char *, int);
179 * Ciphers for SSH2. We miss out single-DES because it isn't
180 * supported; also 3DES and Blowfish are both done differently from
181 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
182 * endianness and different-sized keys.)
184 const static struct ssh_cipher
*ciphers
[] = { &ssh_blowfish_ssh2
, &ssh_3des_ssh2
};
186 extern const struct ssh_kex ssh_diffiehellman
;
187 extern const struct ssh_kex ssh_diffiehellman_gex
;
188 const static struct ssh_kex
*kex_algs
[] = {
189 #ifdef DO_DIFFIE_HELLMAN_GEX
190 &ssh_diffiehellman_gex
,
192 &ssh_diffiehellman
};
194 extern const struct ssh_signkey ssh_dss
;
195 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_dss
};
197 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
199 static void nullmac_key(unsigned char *key
) { }
200 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
201 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
202 const static struct ssh_mac ssh_mac_none
= {
203 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
205 const static struct ssh_mac
*macs
[] = {
206 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
207 const static struct ssh_mac
*buggymacs
[] = {
208 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
210 static void ssh_comp_none_init(void) { }
211 static int ssh_comp_none_block(unsigned char *block
, int len
,
212 unsigned char **outblock
, int *outlen
) {
215 const static struct ssh_compress ssh_comp_none
= {
217 ssh_comp_none_init
, ssh_comp_none_block
,
218 ssh_comp_none_init
, ssh_comp_none_block
220 extern const struct ssh_compress ssh_zlib
;
221 const static struct ssh_compress
*compressions
[] = {
222 &ssh_zlib
, &ssh_comp_none
};
224 enum { /* channel types */
231 * 2-3-4 tree storing channels.
234 unsigned remoteid
, localid
;
237 struct ssh2_data_channel
{
238 unsigned char *outbuffer
;
239 unsigned outbuflen
, outbufsize
;
240 unsigned remwindow
, remmaxpkt
;
243 struct ssh_agent_channel
{
244 unsigned char *message
;
245 unsigned char msglen
[4];
246 int lensofar
, totallen
;
248 struct ssh_x11_channel
{
263 static SHA_State exhash
, exhashbase
;
265 static Socket s
= NULL
;
267 static unsigned char session_key
[32];
268 static int ssh1_compressing
;
269 static int ssh_agentfwd_enabled
;
270 static int ssh_X11_fwd_enabled
;
271 static const struct ssh_cipher
*cipher
= NULL
;
272 static const struct ssh_cipher
*cscipher
= NULL
;
273 static const struct ssh_cipher
*sccipher
= NULL
;
274 static const struct ssh_mac
*csmac
= NULL
;
275 static const struct ssh_mac
*scmac
= NULL
;
276 static const struct ssh_compress
*cscomp
= NULL
;
277 static const struct ssh_compress
*sccomp
= NULL
;
278 static const struct ssh_kex
*kex
= NULL
;
279 static const struct ssh_signkey
*hostkey
= NULL
;
280 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
282 static char *savedhost
;
283 static int savedport
;
284 static int ssh_send_ok
;
285 static int ssh_echoing
, ssh_editing
;
287 static tree234
*ssh_channels
; /* indexed by local id */
288 static struct ssh_channel
*mainchan
; /* primary session channel */
292 SSH_STATE_BEFORE_SIZE
,
296 } ssh_state
= SSH_STATE_PREPACKET
;
298 static int size_needed
= FALSE
, eof_needed
= FALSE
;
300 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
301 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
302 static unsigned char *deferred_send_data
= NULL
;
303 static int deferred_len
= 0, deferred_size
= 0;
305 static int ssh_version
;
306 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
307 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
308 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
309 static void ssh_size(void);
310 static void ssh_special (Telnet_Special
);
311 static void ssh2_try_send(struct ssh_channel
*c
);
312 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
314 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
316 static struct rdpkt1_state_tag
{
317 long len
, pad
, biglen
, to_read
;
318 unsigned long realcrc
, gotcrc
;
324 static struct rdpkt2_state_tag
{
325 long len
, pad
, payload
, packetlen
, maclen
;
328 unsigned long incoming_sequence
;
331 static int ssh_channelcmp(void *av
, void *bv
) {
332 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
333 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
334 if (a
->localid
< b
->localid
) return -1;
335 if (a
->localid
> b
->localid
) return +1;
338 static int ssh_channelfind(void *av
, void *bv
) {
339 unsigned *a
= (unsigned *)av
;
340 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
341 if (*a
< b
->localid
) return -1;
342 if (*a
> b
->localid
) return +1;
346 static void c_write (char *buf
, int len
) {
347 if ((flags
& FLAG_STDERR
)) {
349 for (i
= 0; i
< len
; i
++)
351 fputc(buf
[i
], stderr
);
354 from_backend(1, buf
, len
);
358 * Collect incoming data in the incoming packet buffer.
359 * Decipher and verify the packet when it is completely read.
360 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
361 * Update the *data and *datalen variables.
362 * Return the additional nr of bytes needed, or 0 when
363 * a complete packet is available.
365 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
367 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
376 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
377 while ((*datalen
) == 0)
379 st
->len
= (st
->len
<< 8) + **data
;
380 (*data
)++, (*datalen
)--;
384 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
385 st
->len
= 0x300; /* big enough to carry to end */
389 st
->pad
= 8 - (st
->len
% 8);
390 st
->biglen
= st
->len
+ st
->pad
;
391 pktin
.length
= st
->len
- 5;
393 if (pktin
.maxlen
< st
->biglen
) {
394 pktin
.maxlen
= st
->biglen
;
395 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
396 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
398 fatalbox("Out of memory");
401 st
->to_read
= st
->biglen
;
403 while (st
->to_read
> 0) {
404 st
->chunk
= st
->to_read
;
405 while ((*datalen
) == 0)
406 crReturn(st
->to_read
);
407 if (st
->chunk
> (*datalen
))
408 st
->chunk
= (*datalen
);
409 memcpy(st
->p
, *data
, st
->chunk
);
411 *datalen
-= st
->chunk
;
413 st
->to_read
-= st
->chunk
;
417 cipher
->decrypt(pktin
.data
, st
->biglen
);
419 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
420 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
421 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
425 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
426 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
427 if (st
->gotcrc
!= st
->realcrc
) {
428 bombout(("Incorrect CRC received on packet"));
432 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
434 if (ssh1_compressing
) {
435 unsigned char *decompblk
;
439 debug(("Packet payload pre-decompression:\n"));
440 for (i
= -1; i
< pktin
.length
; i
++)
441 debug((" %02x", (unsigned char)pktin
.body
[i
]));
444 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
445 &decompblk
, &decomplen
);
447 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
448 pktin
.maxlen
= st
->pad
+ decomplen
;
449 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
450 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
452 fatalbox("Out of memory");
455 memcpy(pktin
.body
-1, decompblk
, decomplen
);
457 pktin
.length
= decomplen
-1;
459 debug(("Packet payload post-decompression:\n"));
460 for (i
= -1; i
< pktin
.length
; i
++)
461 debug((" %02x", (unsigned char)pktin
.body
[i
]));
466 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
467 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
468 pktin
.type
== SSH1_MSG_DEBUG
||
469 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
470 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
471 long strlen
= GET_32BIT(pktin
.body
);
472 if (strlen
+ 4 != pktin
.length
) {
473 bombout(("Received data packet with bogus string length"));
478 pktin
.type
= pktin
.body
[-1];
480 if (pktin
.type
== SSH1_MSG_DEBUG
) {
481 /* log debug message */
483 int strlen
= GET_32BIT(pktin
.body
);
484 strcpy(buf
, "Remote: ");
485 if (strlen
> 70) strlen
= 70;
486 memcpy(buf
+8, pktin
.body
+4, strlen
);
487 buf
[8+strlen
] = '\0';
490 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
498 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
500 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
508 st
->cipherblk
= sccipher
->blksize
;
511 if (st
->cipherblk
< 8)
514 if (pktin
.maxlen
< st
->cipherblk
) {
515 pktin
.maxlen
= st
->cipherblk
;
516 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
517 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
519 fatalbox("Out of memory");
523 * Acquire and decrypt the first block of the packet. This will
524 * contain the length and padding details.
526 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
527 while ((*datalen
) == 0)
528 crReturn(st
->cipherblk
-st
->i
);
529 pktin
.data
[st
->i
] = *(*data
)++;
533 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
538 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
541 * Now get the length and padding figures.
543 st
->len
= GET_32BIT(pktin
.data
);
544 st
->pad
= pktin
.data
[4];
547 * This enables us to deduce the payload length.
549 st
->payload
= st
->len
- st
->pad
- 1;
551 pktin
.length
= st
->payload
+ 5;
554 * So now we can work out the total packet length.
556 st
->packetlen
= st
->len
+ 4;
557 st
->maclen
= scmac ? scmac
->len
: 0;
560 * Adjust memory allocation if packet is too big.
562 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
563 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
564 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
565 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
567 fatalbox("Out of memory");
571 * Read and decrypt the remainder of the packet.
573 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
574 while ((*datalen
) == 0)
575 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
576 pktin
.data
[st
->i
] = *(*data
)++;
579 /* Decrypt everything _except_ the MAC. */
581 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
582 st
->packetlen
- st
->cipherblk
);
585 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
586 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
587 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
594 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
595 bombout(("Incorrect MAC received on packet"));
598 st
->incoming_sequence
++; /* whether or not we MACed */
601 * Decompress packet payload.
604 unsigned char *newpayload
;
606 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
607 &newpayload
, &newlen
)) {
608 if (pktin
.maxlen
< newlen
+5) {
609 pktin
.maxlen
= newlen
+5;
610 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
611 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
613 fatalbox("Out of memory");
615 pktin
.length
= 5 + newlen
;
616 memcpy(pktin
.data
+5, newpayload
, newlen
);
618 debug(("Post-decompression payload:\r\n"));
619 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
620 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
629 pktin
.type
= pktin
.data
[5];
631 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
632 goto next_packet
; /* FIXME: print DEBUG message */
637 static void ssh1_pktout_size(int len
) {
640 len
+= 5; /* type and CRC */
644 pktout
.length
= len
-5;
645 if (pktout
.maxlen
< biglen
) {
646 pktout
.maxlen
= biglen
;
648 /* Allocate enough buffer space for extra block
649 * for MS CryptEncrypt() */
650 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
651 srealloc(pktout
.data
, biglen
+12));
653 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
654 srealloc(pktout
.data
, biglen
+4));
657 fatalbox("Out of memory");
659 pktout
.body
= pktout
.data
+4+pad
+1;
662 static void s_wrpkt_start(int type
, int len
) {
663 ssh1_pktout_size(len
);
667 static void s_wrpkt(void) {
668 int pad
, len
, biglen
, i
;
671 pktout
.body
[-1] = pktout
.type
;
673 if (ssh1_compressing
) {
674 unsigned char *compblk
;
677 debug(("Packet payload pre-compression:\n"));
678 for (i
= -1; i
< pktout
.length
; i
++)
679 debug((" %02x", (unsigned char)pktout
.body
[i
]));
682 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
684 ssh1_pktout_size(complen
-1);
685 memcpy(pktout
.body
-1, compblk
, complen
);
688 debug(("Packet payload post-compression:\n"));
689 for (i
= -1; i
< pktout
.length
; i
++)
690 debug((" %02x", (unsigned char)pktout
.body
[i
]));
695 len
= pktout
.length
+ 5; /* type and CRC */
699 for (i
=0; i
<pad
; i
++)
700 pktout
.data
[i
+4] = random_byte();
701 crc
= crc32(pktout
.data
+4, biglen
-4);
702 PUT_32BIT(pktout
.data
+biglen
, crc
);
703 PUT_32BIT(pktout
.data
, len
);
706 debug(("Sending packet len=%d\r\n", biglen
+4));
707 for (i
= 0; i
< biglen
+4; i
++)
708 debug((" %02x", (unsigned char)pktout
.data
[i
]));
712 cipher
->encrypt(pktout
.data
+4, biglen
);
714 sk_write(s
, pktout
.data
, biglen
+4);
718 * Construct a packet with the specified contents and
719 * send it to the server.
721 static void send_packet(int pkttype
, ...)
724 unsigned char *p
, *argp
, argchar
;
725 unsigned long argint
;
726 int pktlen
, argtype
, arglen
;
730 va_start(args
, pkttype
);
731 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
734 (void) va_arg(args
, int);
738 (void) va_arg(args
, char);
742 (void) va_arg(args
, unsigned char *);
743 arglen
= va_arg(args
, int);
747 argp
= va_arg(args
, unsigned char *);
748 arglen
= strlen(argp
);
749 pktlen
+= 4 + arglen
;
752 bn
= va_arg(args
, Bignum
);
753 pktlen
+= ssh1_bignum_length(bn
);
761 s_wrpkt_start(pkttype
, pktlen
);
764 va_start(args
, pkttype
);
765 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
768 argint
= va_arg(args
, int);
769 PUT_32BIT(p
, argint
);
773 argchar
= va_arg(args
, unsigned char);
778 argp
= va_arg(args
, unsigned char *);
779 arglen
= va_arg(args
, int);
780 memcpy(p
, argp
, arglen
);
784 argp
= va_arg(args
, unsigned char *);
785 arglen
= strlen(argp
);
786 PUT_32BIT(p
, arglen
);
787 memcpy(p
+ 4, argp
, arglen
);
791 bn
= va_arg(args
, Bignum
);
792 p
+= ssh1_write_bignum(p
, bn
);
801 static int ssh_versioncmp(char *a
, char *b
) {
803 unsigned long av
, bv
;
805 av
= strtoul(a
, &ae
, 10);
806 bv
= strtoul(b
, &be
, 10);
807 if (av
!= bv
) return (av
< bv ?
-1 : +1);
808 if (*ae
== '.') ae
++;
809 if (*be
== '.') be
++;
810 av
= strtoul(ae
, &ae
, 10);
811 bv
= strtoul(be
, &be
, 10);
812 if (av
!= bv
) return (av
< bv ?
-1 : +1);
818 * Utility routines for putting an SSH-protocol `string' and
819 * `uint32' into a SHA state.
822 static void sha_string(SHA_State
*s
, void *str
, int len
) {
823 unsigned char lenblk
[4];
824 PUT_32BIT(lenblk
, len
);
825 SHA_Bytes(s
, lenblk
, 4);
826 SHA_Bytes(s
, str
, len
);
829 static void sha_uint32(SHA_State
*s
, unsigned i
) {
830 unsigned char intblk
[4];
831 PUT_32BIT(intblk
, i
);
832 SHA_Bytes(s
, intblk
, 4);
836 * SSH2 packet construction functions.
838 static void ssh2_pkt_ensure(int length
) {
839 if (pktout
.maxlen
< length
) {
840 pktout
.maxlen
= length
+ 256;
841 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
842 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
844 fatalbox("Out of memory");
847 static void ssh2_pkt_adddata(void *data
, int len
) {
848 pktout
.length
+= len
;
849 ssh2_pkt_ensure(pktout
.length
);
850 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
852 static void ssh2_pkt_addbyte(unsigned char byte
) {
853 ssh2_pkt_adddata(&byte
, 1);
855 static void ssh2_pkt_init(int pkt_type
) {
857 ssh2_pkt_addbyte((unsigned char)pkt_type
);
859 static void ssh2_pkt_addbool(unsigned char value
) {
860 ssh2_pkt_adddata(&value
, 1);
862 static void ssh2_pkt_adduint32(unsigned long value
) {
865 ssh2_pkt_adddata(x
, 4);
867 static void ssh2_pkt_addstring_start(void) {
868 ssh2_pkt_adduint32(0);
869 pktout
.savedpos
= pktout
.length
;
871 static void ssh2_pkt_addstring_str(char *data
) {
872 ssh2_pkt_adddata(data
, strlen(data
));
873 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
874 pktout
.length
- pktout
.savedpos
);
876 static void ssh2_pkt_addstring_data(char *data
, int len
) {
877 ssh2_pkt_adddata(data
, len
);
878 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
879 pktout
.length
- pktout
.savedpos
);
881 static void ssh2_pkt_addstring(char *data
) {
882 ssh2_pkt_addstring_start();
883 ssh2_pkt_addstring_str(data
);
885 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
887 int i
, n
= (ssh1_bignum_bitcount(b
)+7)/8;
890 fatalbox("out of memory");
892 for (i
= 1; i
<= n
; i
++)
893 p
[i
] = bignum_byte(b
, n
-i
);
895 while (i
<= n
&& p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
897 memmove(p
, p
+i
, n
+1-i
);
901 static void ssh2_pkt_addmp(Bignum b
) {
904 p
= ssh2_mpint_fmt(b
, &len
);
905 ssh2_pkt_addstring_start();
906 ssh2_pkt_addstring_data(p
, len
);
911 * Construct an SSH2 final-form packet: compress it, encrypt it,
912 * put the MAC on it. Final packet, ready to be sent, is stored in
913 * pktout.data. Total length is returned.
915 static int ssh2_pkt_construct(void) {
916 int cipherblk
, maclen
, padding
, i
;
917 static unsigned long outgoing_sequence
= 0;
920 * Compress packet payload.
923 debug(("Pre-compression payload:\r\n"));
924 for (i
= 5; i
< pktout
.length
; i
++)
925 debug((" %02x", (unsigned char)pktout
.data
[i
]));
929 unsigned char *newpayload
;
931 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
932 &newpayload
, &newlen
)) {
934 ssh2_pkt_adddata(newpayload
, newlen
);
940 * Add padding. At least four bytes, and must also bring total
941 * length (minus MAC) up to a multiple of the block size.
943 cipherblk
= cipher ? cipher
->blksize
: 8; /* block size */
944 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
946 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
947 maclen
= csmac ? csmac
->len
: 0;
948 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
949 pktout
.data
[4] = padding
;
950 for (i
= 0; i
< padding
; i
++)
951 pktout
.data
[pktout
.length
+ i
] = random_byte();
952 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
954 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
956 outgoing_sequence
++; /* whether or not we MACed */
959 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
960 for (i
= 0; i
< pktout
.length
+padding
; i
++)
961 debug((" %02x", (unsigned char)pktout
.data
[i
]));
966 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
968 /* Ready-to-send packet starts at pktout.data. We return length. */
969 return pktout
.length
+ padding
+ maclen
;
973 * Construct and send an SSH2 packet immediately.
975 static void ssh2_pkt_send(void) {
976 int len
= ssh2_pkt_construct();
977 sk_write(s
, pktout
.data
, len
);
981 * Construct an SSH2 packet and add it to a deferred data block.
982 * Useful for sending multiple packets in a single sk_write() call,
983 * to prevent a traffic-analysing listener from being able to work
984 * out the length of any particular packet (such as the password
987 * Note that because SSH2 sequence-numbers its packets, this can
988 * NOT be used as an m4-style `defer' allowing packets to be
989 * constructed in one order and sent in another.
991 static void ssh2_pkt_defer(void) {
992 int len
= ssh2_pkt_construct();
993 if (deferred_len
+ len
> deferred_size
) {
994 deferred_size
= deferred_len
+ len
+ 128;
995 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
997 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
1002 * Send the whole deferred data block constructed by
1005 static void ssh2_pkt_defersend(void) {
1006 sk_write(s
, deferred_send_data
, deferred_len
);
1007 deferred_len
= deferred_size
= 0;
1008 sfree(deferred_send_data
);
1009 deferred_send_data
= NULL
;
1013 void bndebug(char *string
, Bignum b
) {
1016 p
= ssh2_mpint_fmt(b
, &len
);
1017 debug(("%s", string
));
1018 for (i
= 0; i
< len
; i
++)
1019 debug((" %02x", p
[i
]));
1025 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1028 p
= ssh2_mpint_fmt(b
, &len
);
1029 sha_string(s
, p
, len
);
1034 * SSH2 packet decode functions.
1036 static unsigned long ssh2_pkt_getuint32(void) {
1037 unsigned long value
;
1038 if (pktin
.length
- pktin
.savedpos
< 4)
1039 return 0; /* arrgh, no way to decline (FIXME?) */
1040 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1041 pktin
.savedpos
+= 4;
1044 static void ssh2_pkt_getstring(char **p
, int *length
) {
1046 if (pktin
.length
- pktin
.savedpos
< 4)
1048 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1049 pktin
.savedpos
+= 4;
1050 if (pktin
.length
- pktin
.savedpos
< *length
)
1052 *p
= pktin
.data
+pktin
.savedpos
;
1053 pktin
.savedpos
+= *length
;
1055 static Bignum
ssh2_pkt_getmp(void) {
1060 ssh2_pkt_getstring(&p
, &length
);
1064 bombout(("internal error: Can't handle negative mpints"));
1067 b
= bignum_from_bytes(p
, length
);
1071 static int do_ssh_init(unsigned char c
) {
1073 static char version
[10];
1074 static char vstring
[80];
1075 static char vlog
[sizeof(vstring
)+20];
1080 /* Search for the string "SSH-" in the input. */
1083 static const int transS
[] = { 1, 2, 2, 1 };
1084 static const int transH
[] = { 0, 0, 3, 0 };
1085 static const int transminus
[] = { 0, 0, 0, -1 };
1086 if (c
== 'S') i
= transS
[i
];
1087 else if (c
== 'H') i
= transH
[i
];
1088 else if (c
== '-') i
= transminus
[i
];
1092 crReturn(1); /* get another character */
1095 strcpy(vstring
, "SSH-");
1099 crReturn(1); /* get another char */
1100 if (vsp
< vstring
+sizeof(vstring
)-1)
1106 } else if (i
< sizeof(version
)-1)
1113 ssh_agentfwd_enabled
= FALSE
;
1114 rdpkt2_state
.incoming_sequence
= 0;
1117 sprintf(vlog
, "Server version: %s", vstring
);
1118 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1122 * Server version "1.99" means we can choose whether we use v1
1123 * or v2 protocol. Choice is based on cfg.sshprot.
1125 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1127 * This is a v2 server. Begin v2 protocol.
1129 char *verstring
= "SSH-2.0-PuTTY";
1130 SHA_Init(&exhashbase
);
1132 * Hash our version string and their version string.
1134 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1135 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1136 sprintf(vstring
, "%s\n", verstring
);
1137 sprintf(vlog
, "We claim version: %s", verstring
);
1139 logevent("Using SSH protocol version 2");
1140 sk_write(s
, vstring
, strlen(vstring
));
1141 ssh_protocol
= ssh2_protocol
;
1143 s_rdpkt
= ssh2_rdpkt
;
1146 * This is a v1 server. Begin v1 protocol.
1148 sprintf(vstring
, "SSH-%s-PuTTY\n",
1149 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1150 sprintf(vlog
, "We claim version: %s", vstring
);
1151 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1153 logevent("Using SSH protocol version 1");
1154 sk_write(s
, vstring
, strlen(vstring
));
1155 ssh_protocol
= ssh1_protocol
;
1157 s_rdpkt
= ssh1_rdpkt
;
1159 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1164 static void ssh_gotdata(unsigned char *data
, int datalen
)
1169 * To begin with, feed the characters one by one to the
1170 * protocol initialisation / selection function do_ssh_init().
1171 * When that returns 0, we're done with the initial greeting
1172 * exchange and can move on to packet discipline.
1177 crReturnV
; /* more data please */
1178 ret
= do_ssh_init(*data
);
1185 * We emerge from that loop when the initial negotiation is
1186 * over and we have selected an s_rdpkt function. Now pass
1187 * everything to s_rdpkt, and then pass the resulting packets
1188 * to the proper protocol handler.
1193 while (datalen
> 0) {
1194 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1195 ssh_protocol(NULL
, 0, 1);
1196 if (ssh_state
== SSH_STATE_CLOSED
) {
1206 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1208 /* A socket error has occurred. */
1209 ssh_state
= SSH_STATE_CLOSED
;
1212 connection_fatal(data
);
1215 /* Connection has closed. */
1216 ssh_state
= SSH_STATE_CLOSED
;
1221 ssh_gotdata (data
, len
);
1222 if (ssh_state
== SSH_STATE_CLOSED
) {
1233 * Connect to specified host and port.
1234 * Returns an error message, or NULL on success.
1235 * Also places the canonical host name into `realhost'.
1237 static char *connect_to_host(char *host
, int port
, char **realhost
)
1246 savedhost
= smalloc(1+strlen(host
));
1248 fatalbox("Out of memory");
1249 strcpy(savedhost
, host
);
1252 port
= 22; /* default ssh port */
1265 addr
= sk_namelookup(host
, realhost
);
1266 if ( (err
= sk_addr_error(addr
)) )
1276 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1277 if ( (err
= sk_socket_error(s
)) )
1281 sk_write(s
, "connect ", 8);
1282 sk_write(s
, FWhost
, strlen(FWhost
));
1285 sprintf(buf
, " %d\n", FWport
);
1286 sk_write(s
, buf
, strlen(buf
));
1294 * Handle the key exchange and user authentication phases.
1296 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1299 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1300 unsigned char cookie
[8];
1301 struct RSAKey servkey
, hostkey
;
1302 struct MD5Context md5c
;
1303 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1304 static int tried_publickey
;
1305 static unsigned char session_id
[16];
1307 static char username
[100];
1311 if (!ispkt
) crWaitUntil(ispkt
);
1313 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1314 bombout(("Public key packet not received"));
1318 logevent("Received public keys");
1320 memcpy(cookie
, pktin
.body
, 8);
1322 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1323 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1326 * Log the host key fingerprint.
1330 logevent("Host key fingerprint is:");
1331 strcpy(logmsg
, " ");
1332 hostkey
.comment
= NULL
;
1333 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1338 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1339 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1342 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1343 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1344 MD5Update(&md5c
, pktin
.body
, 8);
1345 MD5Final(session_id
, &md5c
);
1347 for (i
=0; i
<32; i
++)
1348 session_key
[i
] = random_byte();
1350 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1352 rsabuf
= smalloc(len
);
1354 fatalbox("Out of memory");
1357 * Verify the host key.
1361 * First format the key into a string.
1363 int len
= rsastr_len(&hostkey
);
1364 char fingerprint
[100];
1365 char *keystr
= smalloc(len
);
1367 fatalbox("Out of memory");
1368 rsastr_fmt(keystr
, &hostkey
);
1369 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1370 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1374 for (i
=0; i
<32; i
++) {
1375 rsabuf
[i
] = session_key
[i
];
1377 rsabuf
[i
] ^= session_id
[i
];
1380 if (hostkey
.bytes
> servkey
.bytes
) {
1381 rsaencrypt(rsabuf
, 32, &servkey
);
1382 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1384 rsaencrypt(rsabuf
, 32, &hostkey
);
1385 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1388 logevent("Encrypted session key");
1390 cipher_type
= cfg
.cipher
== CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH
:
1391 cfg
.cipher
== CIPHER_DES ? SSH_CIPHER_DES
:
1393 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1394 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1395 cipher_type
= SSH_CIPHER_3DES
;
1397 switch (cipher_type
) {
1398 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1399 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1400 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1403 send_packet(SSH1_CMSG_SESSION_KEY
,
1404 PKT_CHAR
, cipher_type
,
1405 PKT_DATA
, cookie
, 8,
1406 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1407 PKT_DATA
, rsabuf
, len
,
1411 logevent("Trying to enable encryption...");
1415 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1416 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1418 cipher
->sesskey(session_key
);
1422 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1423 bombout(("Encryption not successfully enabled"));
1427 logevent("Successfully started encryption");
1433 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1434 c_write("login as: ", 10);
1437 crWaitUntil(!ispkt
);
1438 while (inlen
--) switch (c
= *in
++) {
1445 c_write("\b \b", 3);
1451 c_write("\b \b", 3);
1460 if (((c
>= ' ' && c
<= '~') ||
1461 ((unsigned char)c
>= 160)) && pos
< 40) {
1462 username
[pos
++] = c
;
1469 username
[strcspn(username
, "\n\r")] = '\0';
1471 strncpy(username
, cfg
.username
, 99);
1472 username
[99] = '\0';
1475 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1477 char userlog
[22+sizeof(username
)];
1478 sprintf(userlog
, "Sent username \"%s\"", username
);
1480 if (flags
& FLAG_INTERACTIVE
&&
1481 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1482 strcat(userlog
, "\r\n");
1483 c_write(userlog
, strlen(userlog
));
1490 tried_publickey
= 0;
1492 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1493 static char password
[100];
1494 static char prompt
[200];
1497 static int pwpkt_type
;
1499 * Show password prompt, having first obtained it via a TIS
1500 * or CryptoCard exchange if we're doing TIS or CryptoCard
1503 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1504 if (agent_exists()) {
1506 * Attempt RSA authentication using Pageant.
1508 static unsigned char request
[5], *response
, *p
;
1509 static int responselen
;
1510 static int i
, nkeys
;
1511 static int authed
= FALSE
;
1514 logevent("Pageant is running. Requesting keys.");
1516 /* Request the keys held by the agent. */
1517 PUT_32BIT(request
, 1);
1518 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1519 agent_query(request
, 5, &r
, &responselen
);
1520 response
= (unsigned char *)r
;
1523 nkeys
= GET_32BIT(p
); p
+= 4;
1524 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1526 for (i
= 0; i
< nkeys
; i
++) {
1527 static struct RSAKey key
;
1528 static Bignum challenge
;
1529 static char *commentp
;
1530 static int commentlen
;
1532 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1535 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1536 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1537 commentlen
= GET_32BIT(p
); p
+= 4;
1538 commentp
= p
; p
+= commentlen
;
1539 send_packet(SSH1_CMSG_AUTH_RSA
,
1540 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1542 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1543 logevent("Key refused");
1546 logevent("Received RSA challenge");
1547 ssh1_read_bignum(pktin
.body
, &challenge
);
1549 char *agentreq
, *q
, *ret
;
1551 len
= 1 + 4; /* message type, bit count */
1552 len
+= ssh1_bignum_length(key
.exponent
);
1553 len
+= ssh1_bignum_length(key
.modulus
);
1554 len
+= ssh1_bignum_length(challenge
);
1555 len
+= 16; /* session id */
1556 len
+= 4; /* response format */
1557 agentreq
= smalloc(4 + len
);
1558 PUT_32BIT(agentreq
, len
);
1560 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1561 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1563 q
+= ssh1_write_bignum(q
, key
.exponent
);
1564 q
+= ssh1_write_bignum(q
, key
.modulus
);
1565 q
+= ssh1_write_bignum(q
, challenge
);
1566 memcpy(q
, session_id
, 16); q
+= 16;
1567 PUT_32BIT(q
, 1); /* response format */
1568 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1571 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1572 logevent("Sending Pageant's response");
1573 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1574 PKT_DATA
, ret
+5, 16, PKT_END
);
1577 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1578 logevent("Pageant's response accepted");
1579 if (flags
& FLAG_VERBOSE
) {
1580 c_write("Authenticated using RSA key \"",
1582 c_write(commentp
, commentlen
);
1583 c_write("\" from agent\r\n", 14);
1587 logevent("Pageant's response not accepted");
1589 logevent("Pageant failed to answer challenge");
1593 logevent("No reply received from Pageant");
1596 freebn(key
.exponent
);
1597 freebn(key
.modulus
);
1606 if (*cfg
.keyfile
&& !tried_publickey
)
1607 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1609 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1611 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1612 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1613 logevent("Requested TIS authentication");
1614 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1616 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1617 logevent("TIS authentication declined");
1618 if (flags
& FLAG_INTERACTIVE
)
1619 c_write("TIS authentication refused.\r\n", 29);
1621 int challengelen
= ((pktin
.body
[0] << 24) |
1622 (pktin
.body
[1] << 16) |
1623 (pktin
.body
[2] << 8) |
1625 logevent("Received TIS challenge");
1626 if (challengelen
> sizeof(prompt
)-1)
1627 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1628 memcpy(prompt
, pktin
.body
+4, challengelen
);
1629 prompt
[challengelen
] = '\0';
1632 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1634 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1635 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1636 logevent("Requested CryptoCard authentication");
1637 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1639 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1640 logevent("CryptoCard authentication declined");
1641 c_write("CryptoCard authentication refused.\r\n", 29);
1643 int challengelen
= ((pktin
.body
[0] << 24) |
1644 (pktin
.body
[1] << 16) |
1645 (pktin
.body
[2] << 8) |
1647 logevent("Received CryptoCard challenge");
1648 if (challengelen
> sizeof(prompt
)-1)
1649 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1650 memcpy(prompt
, pktin
.body
+4, challengelen
);
1651 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1652 sizeof(prompt
)-challengelen
);
1653 prompt
[sizeof(prompt
)-1] = '\0';
1656 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1657 sprintf(prompt
, "%.90s@%.90s's password: ",
1658 username
, savedhost
);
1660 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1661 char *comment
= NULL
;
1662 if (flags
& FLAG_VERBOSE
)
1663 c_write("Trying public key authentication.\r\n", 35);
1664 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1665 if (flags
& FLAG_VERBOSE
)
1666 c_write("No passphrase required.\r\n", 25);
1669 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1673 if (ssh_get_password
) {
1674 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1676 * get_password failed to get a password (for
1677 * example because one was supplied on the command
1678 * line which has already failed to work).
1681 logevent("No more passwords to try");
1682 ssh_state
= SSH_STATE_CLOSED
;
1686 c_write(prompt
, strlen(prompt
));
1690 crWaitUntil(!ispkt
);
1691 while (inlen
--) switch (c
= *in
++) {
1708 if (((c
>= ' ' && c
<= '~') ||
1709 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1710 password
[pos
++] = c
;
1718 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1720 * Try public key authentication with the specified
1723 static struct RSAKey pubkey
;
1724 static Bignum challenge
, response
;
1726 static unsigned char buffer
[32];
1728 tried_publickey
= 1;
1729 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1731 c_write("Couldn't load public key from ", 30);
1732 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1733 c_write(".\r\n", 3);
1734 continue; /* go and try password */
1737 c_write("Wrong passphrase.\r\n", 19);
1738 tried_publickey
= 0;
1739 continue; /* try again */
1743 * Send a public key attempt.
1745 send_packet(SSH1_CMSG_AUTH_RSA
,
1746 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1749 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1750 c_write("Server refused our public key.\r\n", 32);
1751 continue; /* go and try password */
1753 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1754 bombout(("Bizarre response to offer of public key"));
1757 ssh1_read_bignum(pktin
.body
, &challenge
);
1758 response
= rsadecrypt(challenge
, &pubkey
);
1759 freebn(pubkey
.private_exponent
); /* burn the evidence */
1761 for (i
= 0; i
< 32; i
++) {
1762 buffer
[i
] = bignum_byte(response
, 31-i
);
1766 MD5Update(&md5c
, buffer
, 32);
1767 MD5Update(&md5c
, session_id
, 16);
1768 MD5Final(buffer
, &md5c
);
1770 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1771 PKT_DATA
, buffer
, 16, PKT_END
);
1774 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1775 if (flags
& FLAG_VERBOSE
)
1776 c_write("Failed to authenticate with our public key.\r\n",
1778 continue; /* go and try password */
1779 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1780 bombout(("Bizarre response to RSA authentication response"));
1784 break; /* we're through! */
1786 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1788 logevent("Sent password");
1789 memset(password
, 0, strlen(password
));
1791 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1792 if (flags
& FLAG_VERBOSE
)
1793 c_write("Access denied\r\n", 15);
1794 logevent("Authentication refused");
1795 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1796 logevent("Received disconnect request");
1797 ssh_state
= SSH_STATE_CLOSED
;
1799 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1800 bombout(("Strange packet received, type %d", pktin
.type
));
1805 logevent("Authentication successful");
1810 void sshfwd_close(struct ssh_channel
*c
) {
1812 if (ssh_version
== 1) {
1813 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1815 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1816 ssh2_pkt_adduint32(c
->remoteid
);
1820 if (c
->type
== CHAN_X11
) {
1822 logevent("X11 connection terminated");
1827 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1828 if (ssh_version
== 1) {
1829 send_packet(SSH1_MSG_CHANNEL_DATA
,
1830 PKT_INT
, c
->remoteid
,
1835 ssh2_add_channel_data(c
, buf
, len
);
1840 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1845 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1848 if (ssh_state
== SSH_STATE_CLOSED
)
1851 if (cfg
.agentfwd
&& agent_exists()) {
1852 logevent("Requesting agent forwarding");
1853 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1854 do { crReturnV
; } while (!ispkt
);
1855 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1856 bombout(("Protocol confusion"));
1858 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1859 logevent("Agent forwarding refused");
1861 logevent("Agent forwarding enabled");
1862 ssh_agentfwd_enabled
= TRUE
;
1866 if (cfg
.x11_forward
) {
1867 char proto
[20], data
[64];
1868 logevent("Requesting X11 forwarding");
1869 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1870 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1871 PKT_STR
, proto
, PKT_STR
, data
,
1874 do { crReturnV
; } while (!ispkt
);
1875 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1876 bombout(("Protocol confusion"));
1878 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1879 logevent("X11 forwarding refused");
1881 logevent("X11 forwarding enabled");
1882 ssh_X11_fwd_enabled
= TRUE
;
1887 send_packet(SSH1_CMSG_REQUEST_PTY
,
1888 PKT_STR
, cfg
.termtype
,
1889 PKT_INT
, rows
, PKT_INT
, cols
,
1890 PKT_INT
, 0, PKT_INT
, 0,
1893 ssh_state
= SSH_STATE_INTERMED
;
1894 do { crReturnV
; } while (!ispkt
);
1895 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1896 bombout(("Protocol confusion"));
1898 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1899 c_write("Server refused to allocate pty\r\n", 32);
1900 ssh_editing
= ssh_echoing
= 1;
1902 logevent("Allocated pty");
1904 ssh_editing
= ssh_echoing
= 1;
1907 if (cfg
.compression
) {
1908 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1909 do { crReturnV
; } while (!ispkt
);
1910 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1911 bombout(("Protocol confusion"));
1913 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1914 c_write("Server refused to compress\r\n", 32);
1916 logevent("Started compression");
1917 ssh1_compressing
= TRUE
;
1918 zlib_compress_init();
1919 zlib_decompress_init();
1922 if (*cfg
.remote_cmd
)
1923 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1925 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1926 logevent("Started session");
1928 ssh_state
= SSH_STATE_SESSION
;
1932 ssh_special(TS_EOF
);
1934 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
1936 ssh_channels
= newtree234(ssh_channelcmp
);
1940 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1941 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1942 long len
= GET_32BIT(pktin
.body
);
1943 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
1945 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1946 ssh_state
= SSH_STATE_CLOSED
;
1947 logevent("Received disconnect request");
1949 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
1950 /* Remote side is trying to open a channel to talk to our
1951 * X-Server. Give them back a local channel number. */
1953 struct ssh_channel
*c
, *d
;
1956 logevent("Received X11 connect request");
1957 /* Refuse if X11 forwarding is disabled. */
1958 if (!ssh_X11_fwd_enabled
) {
1959 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1960 PKT_INT
, GET_32BIT(pktin
.body
),
1962 logevent("Rejected X11 connect request");
1964 c
= smalloc(sizeof(struct ssh_channel
));
1966 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
1967 logevent("opening X11 forward connection failed");
1969 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1970 PKT_INT
, GET_32BIT(pktin
.body
),
1973 logevent("opening X11 forward connection succeeded");
1974 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
1976 break; /* found a free number */
1979 c
->remoteid
= GET_32BIT(pktin
.body
);
1982 c
->type
= CHAN_X11
; /* identify channel type */
1983 add234(ssh_channels
, c
);
1984 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1985 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1987 logevent("Opened X11 forward channel");
1990 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
1991 /* Remote side is trying to open a channel to talk to our
1992 * agent. Give them back a local channel number. */
1994 struct ssh_channel
*c
;
1997 /* Refuse if agent forwarding is disabled. */
1998 if (!ssh_agentfwd_enabled
) {
1999 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2000 PKT_INT
, GET_32BIT(pktin
.body
),
2004 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
2006 break; /* found a free number */
2009 c
= smalloc(sizeof(struct ssh_channel
));
2010 c
->remoteid
= GET_32BIT(pktin
.body
);
2013 c
->type
= CHAN_AGENT
; /* identify channel type */
2014 c
->u
.a
.lensofar
= 0;
2015 add234(ssh_channels
, c
);
2016 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2017 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2020 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2021 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2022 /* Remote side closes a channel. */
2023 unsigned i
= GET_32BIT(pktin
.body
);
2024 struct ssh_channel
*c
;
2025 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2028 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2029 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2030 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2031 logevent("X11 connection closed");
2032 assert(c
->u
.x11
.s
!= NULL
);
2033 x11_close(c
->u
.x11
.s
);
2036 c
->closes
|= closetype
;
2037 if (c
->closes
== 3) {
2038 del234(ssh_channels
, c
);
2042 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2043 /* Data sent down one of our channels. */
2044 int i
= GET_32BIT(pktin
.body
);
2045 int len
= GET_32BIT(pktin
.body
+4);
2046 unsigned char *p
= pktin
.body
+8;
2047 struct ssh_channel
*c
;
2048 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2052 x11_send(c
->u
.x11
.s
, p
, len
);
2055 /* Data for an agent message. Buffer it. */
2057 if (c
->u
.a
.lensofar
< 4) {
2058 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2059 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2060 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2062 if (c
->u
.a
.lensofar
== 4) {
2063 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2064 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2065 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2067 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2068 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2069 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2070 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2072 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2073 void *reply
, *sentreply
;
2075 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2080 /* Fake SSH_AGENT_FAILURE. */
2081 sentreply
= "\0\0\0\1\5";
2084 send_packet(SSH1_MSG_CHANNEL_DATA
,
2085 PKT_INT
, c
->remoteid
,
2087 PKT_DATA
, sentreply
, replylen
,
2091 sfree(c
->u
.a
.message
);
2092 c
->u
.a
.lensofar
= 0;
2098 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2099 /* may be from EXEC_SHELL on some servers */
2100 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2101 /* may be from EXEC_SHELL on some servers
2102 * if no pty is available or in other odd cases. Ignore */
2103 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2104 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2106 bombout(("Strange packet received: type %d", pktin
.type
));
2111 int len
= min(inlen
, 512);
2112 send_packet(SSH1_CMSG_STDIN_DATA
,
2113 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2124 * Utility routine for decoding comma-separated strings in KEXINIT.
2126 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2127 int needlen
= strlen(needle
);
2130 * Is it at the start of the string?
2132 if (haylen
>= needlen
&& /* haystack is long enough */
2133 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2134 (haylen
== needlen
|| haystack
[needlen
] == ',')
2135 /* either , or EOS follows */
2139 * If not, search for the next comma and resume after that.
2140 * If no comma found, terminate.
2142 while (haylen
> 0 && *haystack
!= ',')
2143 haylen
--, haystack
++;
2146 haylen
--, haystack
++; /* skip over comma itself */
2151 * SSH2 key creation method.
2153 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2155 /* First 20 bytes. */
2158 SHA_Bytes(&s
, H
, 20);
2159 SHA_Bytes(&s
, &chr
, 1);
2160 SHA_Bytes(&s
, sessid
, 20);
2161 SHA_Final(&s
, keyspace
);
2162 /* Next 20 bytes. */
2165 SHA_Bytes(&s
, H
, 20);
2166 SHA_Bytes(&s
, keyspace
, 20);
2167 SHA_Final(&s
, keyspace
+20);
2171 * Handle the SSH2 transport layer.
2173 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2175 static int i
, len
, nbits
;
2177 static Bignum p
, g
, e
, f
, K
;
2178 static int kex_init_value
, kex_reply_value
;
2179 static const struct ssh_mac
**maclist
;
2181 static const struct ssh_cipher
*cscipher_tobe
= NULL
;
2182 static const struct ssh_cipher
*sccipher_tobe
= NULL
;
2183 static const struct ssh_mac
*csmac_tobe
= NULL
;
2184 static const struct ssh_mac
*scmac_tobe
= NULL
;
2185 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2186 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2187 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2188 static int hostkeylen
, siglen
;
2189 static void *hkey
; /* actual host key */
2190 static unsigned char exchange_hash
[20];
2191 static unsigned char first_exchange_hash
[20];
2192 static unsigned char keyspace
[40];
2193 static const struct ssh_cipher
*preferred_cipher
;
2194 static const struct ssh_compress
*preferred_comp
;
2195 static int first_kex
;
2202 * Set up the preferred cipher and compression.
2204 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2205 preferred_cipher
= &ssh_blowfish_ssh2
;
2206 } else if (cfg
.cipher
== CIPHER_DES
) {
2207 logevent("Single DES not supported in SSH2; using 3DES");
2208 preferred_cipher
= &ssh_3des_ssh2
;
2209 } else if (cfg
.cipher
== CIPHER_3DES
) {
2210 preferred_cipher
= &ssh_3des_ssh2
;
2212 /* Shouldn't happen, but we do want to initialise to _something_. */
2213 preferred_cipher
= &ssh_3des_ssh2
;
2215 if (cfg
.compression
)
2216 preferred_comp
= &ssh_zlib
;
2218 preferred_comp
= &ssh_comp_none
;
2221 * Be prepared to work around the buggy MAC problem.
2224 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2226 maclist
= macs
, nmacs
= lenof(macs
);
2230 * Construct and send our key exchange packet.
2232 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2233 for (i
= 0; i
< 16; i
++)
2234 ssh2_pkt_addbyte((unsigned char)random_byte());
2235 /* List key exchange algorithms. */
2236 ssh2_pkt_addstring_start();
2237 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2238 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2239 if (i
< lenof(kex_algs
)-1)
2240 ssh2_pkt_addstring_str(",");
2242 /* List server host key algorithms. */
2243 ssh2_pkt_addstring_start();
2244 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2245 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2246 if (i
< lenof(hostkey_algs
)-1)
2247 ssh2_pkt_addstring_str(",");
2249 /* List client->server encryption algorithms. */
2250 ssh2_pkt_addstring_start();
2251 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2252 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2253 ssh2_pkt_addstring_str(c
->name
);
2254 if (i
< lenof(ciphers
))
2255 ssh2_pkt_addstring_str(",");
2257 /* List server->client encryption algorithms. */
2258 ssh2_pkt_addstring_start();
2259 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2260 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2261 ssh2_pkt_addstring_str(c
->name
);
2262 if (i
< lenof(ciphers
))
2263 ssh2_pkt_addstring_str(",");
2265 /* List client->server MAC algorithms. */
2266 ssh2_pkt_addstring_start();
2267 for (i
= 0; i
< nmacs
; i
++) {
2268 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2270 ssh2_pkt_addstring_str(",");
2272 /* List server->client MAC algorithms. */
2273 ssh2_pkt_addstring_start();
2274 for (i
= 0; i
< nmacs
; i
++) {
2275 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2277 ssh2_pkt_addstring_str(",");
2279 /* List client->server compression algorithms. */
2280 ssh2_pkt_addstring_start();
2281 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2282 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2283 ssh2_pkt_addstring_str(c
->name
);
2284 if (i
< lenof(compressions
))
2285 ssh2_pkt_addstring_str(",");
2287 /* List server->client compression algorithms. */
2288 ssh2_pkt_addstring_start();
2289 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2290 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2291 ssh2_pkt_addstring_str(c
->name
);
2292 if (i
< lenof(compressions
))
2293 ssh2_pkt_addstring_str(",");
2295 /* List client->server languages. Empty list. */
2296 ssh2_pkt_addstring_start();
2297 /* List server->client languages. Empty list. */
2298 ssh2_pkt_addstring_start();
2299 /* First KEX packet does _not_ follow, because we're not that brave. */
2300 ssh2_pkt_addbool(FALSE
);
2302 ssh2_pkt_adduint32(0);
2304 exhash
= exhashbase
;
2305 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2309 if (!ispkt
) crWaitUntil(ispkt
);
2310 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2313 * Now examine the other side's KEXINIT to see what we're up
2316 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2317 bombout(("expected key exchange packet from server"));
2320 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2321 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2322 pktin
.savedpos
+= 16; /* skip garbage cookie */
2323 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2324 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2325 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2330 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2331 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2332 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2333 hostkey
= hostkey_algs
[i
];
2337 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2338 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2339 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2340 if (in_commasep_string(c
->name
, str
, len
)) {
2345 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2346 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2347 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2348 if (in_commasep_string(c
->name
, str
, len
)) {
2353 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2354 for (i
= 0; i
< nmacs
; i
++) {
2355 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2356 csmac_tobe
= maclist
[i
];
2360 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2361 for (i
= 0; i
< nmacs
; i
++) {
2362 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2363 scmac_tobe
= maclist
[i
];
2367 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2368 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2369 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2370 if (in_commasep_string(c
->name
, str
, len
)) {
2375 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2376 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2377 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2378 if (in_commasep_string(c
->name
, str
, len
)) {
2385 * If we're doing Diffie-Hellman group exchange, start by
2386 * requesting a group.
2388 if (kex
== &ssh_diffiehellman_gex
) {
2391 logevent("Doing Diffie-Hellman group exchange");
2393 * Work out number of bits. We start with the maximum key
2394 * length of either cipher...
2396 csbits
= cscipher_tobe
->keylen
;
2397 scbits
= sccipher_tobe
->keylen
;
2398 nbits
= (csbits
> scbits ? csbits
: scbits
);
2399 /* The keys only have 160-bit entropy, since they're based on
2400 * a SHA-1 hash. So cap the key size at 160 bits. */
2401 if (nbits
> 160) nbits
= 160;
2403 * ... and then work out how big a DH group we will need to
2404 * allow that much data.
2406 nbits
= 512 << ((nbits
-1) / 64);
2407 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
2408 ssh2_pkt_adduint32(nbits
);
2412 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
2413 bombout(("expected key exchange group packet from server"));
2416 p
= ssh2_pkt_getmp();
2417 g
= ssh2_pkt_getmp();
2418 dh_setup_group(p
, g
);
2419 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
2420 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
2423 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
2424 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
2427 logevent("Doing Diffie-Hellman key exchange");
2429 * Now generate and send e for Diffie-Hellman.
2432 ssh2_pkt_init(kex_init_value
);
2437 if (pktin
.type
!= kex_reply_value
) {
2438 bombout(("expected key exchange reply packet from server"));
2441 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2442 f
= ssh2_pkt_getmp();
2443 ssh2_pkt_getstring(&sigdata
, &siglen
);
2447 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2448 if (kex
== &ssh_diffiehellman_gex
) {
2449 sha_uint32(&exhash
, nbits
);
2450 sha_mpint(&exhash
, p
);
2451 sha_mpint(&exhash
, g
);
2453 sha_mpint(&exhash
, e
);
2454 sha_mpint(&exhash
, f
);
2455 sha_mpint(&exhash
, K
);
2456 SHA_Final(&exhash
, exchange_hash
);
2461 debug(("Exchange hash is:\r\n"));
2462 for (i
= 0; i
< 20; i
++)
2463 debug((" %02x", exchange_hash
[i
]));
2467 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2468 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2469 bombout(("Server failed host key check"));
2474 * Expect SSH2_MSG_NEWKEYS from server.
2477 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2478 bombout(("expected new-keys packet from server"));
2483 * Authenticate remote host: verify host key. (We've already
2484 * checked the signature of the exchange hash.)
2486 keystr
= hostkey
->fmtkey(hkey
);
2487 fingerprint
= hostkey
->fingerprint(hkey
);
2488 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2489 keystr
, fingerprint
);
2490 if (first_kex
) { /* don't bother logging this in rekeys */
2491 logevent("Host key fingerprint is:");
2492 logevent(fingerprint
);
2496 hostkey
->freekey(hkey
);
2499 * Send SSH2_MSG_NEWKEYS.
2501 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2505 * Create and initialise session keys.
2507 cscipher
= cscipher_tobe
;
2508 sccipher
= sccipher_tobe
;
2511 cscomp
= cscomp_tobe
;
2512 sccomp
= sccomp_tobe
;
2513 cscomp
->compress_init();
2514 sccomp
->decompress_init();
2516 * Set IVs after keys. Here we use the exchange hash from the
2517 * _first_ key exchange.
2520 memcpy(first_exchange_hash
, exchange_hash
, sizeof(exchange_hash
));
2521 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'C', keyspace
);
2522 cscipher
->setcskey(keyspace
);
2523 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'D', keyspace
);
2524 sccipher
->setsckey(keyspace
);
2525 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'A', keyspace
);
2526 cscipher
->setcsiv(keyspace
);
2527 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'B', keyspace
);
2528 sccipher
->setsciv(keyspace
);
2529 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'E', keyspace
);
2530 csmac
->setcskey(keyspace
);
2531 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'F', keyspace
);
2532 scmac
->setsckey(keyspace
);
2535 * If this is the first key exchange phase, we must pass the
2536 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2537 * wants to see it but because it will need time to initialise
2538 * itself before it sees an actual packet. In subsequent key
2539 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2540 * it would only confuse the layer above.
2548 * Now we're encrypting. Begin returning 1 to the protocol main
2549 * function so that other things can run on top of the
2550 * transport. If we ever see a KEXINIT, we must go back to the
2553 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2556 logevent("Server initiated key re-exchange");
2557 goto begin_key_exchange
;
2563 * Add data to an SSH2 channel output buffer.
2565 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2566 if (c
->v2
.outbufsize
<
2567 c
->v2
.outbuflen
+ len
) {
2569 c
->v2
.outbuflen
+ len
+ 1024;
2570 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2573 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2575 c
->v2
.outbuflen
+= len
;
2579 * Attempt to send data on an SSH2 channel.
2581 static void ssh2_try_send(struct ssh_channel
*c
) {
2582 while (c
->v2
.remwindow
> 0 &&
2583 c
->v2
.outbuflen
> 0) {
2584 unsigned len
= c
->v2
.remwindow
;
2585 if (len
> c
->v2
.outbuflen
)
2586 len
= c
->v2
.outbuflen
;
2587 if (len
> c
->v2
.remmaxpkt
)
2588 len
= c
->v2
.remmaxpkt
;
2589 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2590 ssh2_pkt_adduint32(c
->remoteid
);
2591 ssh2_pkt_addstring_start();
2592 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2594 c
->v2
.outbuflen
-= len
;
2595 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2597 c
->v2
.remwindow
-= len
;
2602 * Handle the SSH2 userauth and connection layers.
2604 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2606 static unsigned long remote_winsize
;
2607 static unsigned long remote_maxpkt
;
2612 * Request userauth protocol, and await a response to it.
2614 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2615 ssh2_pkt_addstring("ssh-userauth");
2617 crWaitUntilV(ispkt
);
2618 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2619 bombout(("Server refused user authentication protocol"));
2624 * FIXME: currently we support only password authentication.
2625 * (This places us technically in violation of the SSH2 spec.
2626 * We must fix this.)
2630 * Get a username and a password.
2632 static char username
[100];
2633 static char password
[100];
2637 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2638 c_write("login as: ", 10);
2641 crWaitUntilV(!ispkt
);
2642 while (inlen
--) switch (c
= *in
++) {
2649 c_write("\b \b", 3);
2655 c_write("\b \b", 3);
2664 if (((c
>= ' ' && c
<= '~') ||
2665 ((unsigned char)c
>= 160)) && pos
< 40) {
2666 username
[pos
++] = c
;
2673 username
[strcspn(username
, "\n\r")] = '\0';
2676 strncpy(username
, cfg
.username
, 99);
2677 username
[99] = '\0';
2678 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2679 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2680 c_write(stuff
, strlen(stuff
));
2684 if (ssh_get_password
) {
2686 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2687 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2689 * get_password failed to get a password (for
2690 * example because one was supplied on the command
2691 * line which has already failed to work).
2694 logevent("No more passwords to try");
2695 ssh_state
= SSH_STATE_CLOSED
;
2699 c_write("password: ", 10);
2704 crWaitUntilV(!ispkt
);
2705 while (inlen
--) switch (c
= *in
++) {
2722 if (((c
>= ' ' && c
<= '~') ||
2723 ((unsigned char)c
>= 160)) && pos
< 40)
2724 password
[pos
++] = c
;
2732 * We send the password packet lumped tightly together with
2733 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
2734 * string long enough to make the total length of the two
2735 * packets constant. This should ensure that a passive
2736 * listener doing traffic analyis can't work out the length
2739 * For this to work, we need an assumption about the
2740 * maximum length of the password packet. I think 256 is
2741 * pretty conservative. Anyone using a password longer than
2742 * that probably doesn't have much to worry about from
2743 * people who find out how long their password is!
2745 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2746 ssh2_pkt_addstring(username
);
2747 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2748 ssh2_pkt_addstring("password");
2749 ssh2_pkt_addbool(FALSE
);
2750 ssh2_pkt_addstring(password
);
2753 * We'll include a string that's an exact multiple of the
2754 * cipher block size. If the cipher is NULL for some
2755 * reason, we don't do this trick at all because we gain
2760 ssh2_pkt_init(SSH2_MSG_IGNORE
);
2761 ssh2_pkt_addstring_start();
2762 for (i
= deferred_len
; i
<= 256; i
+= cscipher
->blksize
) {
2763 for (j
= 0; j
< cscipher
->blksize
; j
++) {
2764 char c
= (char)random_byte();
2765 ssh2_pkt_addstring_data(&c
, 1);
2770 ssh2_pkt_defersend();
2772 crWaitUntilV(ispkt
);
2773 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2774 c_write("Access denied\r\n", 15);
2775 logevent("Authentication refused");
2781 * Now we're authenticated for the connection protocol. The
2782 * connection protocol will automatically have started at this
2783 * point; there's no need to send SERVICE_REQUEST.
2787 * So now create a channel with a session in it.
2789 mainchan
= smalloc(sizeof(struct ssh_channel
));
2790 mainchan
->localid
= 100; /* as good as any */
2791 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2792 ssh2_pkt_addstring("session");
2793 ssh2_pkt_adduint32(mainchan
->localid
);
2794 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2795 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2797 crWaitUntilV(ispkt
);
2798 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2799 bombout(("Server refused to open a session"));
2801 /* FIXME: error data comes back in FAILURE packet */
2803 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2804 bombout(("Server's channel confirmation cited wrong channel"));
2807 mainchan
->remoteid
= ssh2_pkt_getuint32();
2808 mainchan
->type
= CHAN_MAINSESSION
;
2809 mainchan
->closes
= 0;
2810 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
2811 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2812 mainchan
->v2
.outbuffer
= NULL
;
2813 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
2814 ssh_channels
= newtree234(ssh_channelcmp
);
2815 add234(ssh_channels
, mainchan
);
2816 logevent("Opened channel for session");
2819 * Potentially enable X11 forwarding.
2821 if (cfg
.x11_forward
) {
2822 char proto
[20], data
[64];
2823 logevent("Requesting X11 forwarding");
2824 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2825 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2826 ssh2_pkt_adduint32(mainchan
->remoteid
);
2827 ssh2_pkt_addstring("x11-req");
2828 ssh2_pkt_addbool(1); /* want reply */
2829 ssh2_pkt_addbool(0); /* many connections */
2830 ssh2_pkt_addstring(proto
);
2831 ssh2_pkt_addstring(data
);
2832 ssh2_pkt_adduint32(0); /* screen number */
2836 crWaitUntilV(ispkt
);
2837 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2838 unsigned i
= ssh2_pkt_getuint32();
2839 struct ssh_channel
*c
;
2840 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2842 continue; /* nonexistent channel */
2843 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2845 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2847 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2848 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2849 bombout(("Server got confused by X11 forwarding request"));
2852 logevent("X11 forwarding refused");
2854 logevent("X11 forwarding enabled");
2855 ssh_X11_fwd_enabled
= TRUE
;
2860 * Now allocate a pty for the session.
2863 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2864 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2865 ssh2_pkt_addstring("pty-req");
2866 ssh2_pkt_addbool(1); /* want reply */
2867 ssh2_pkt_addstring(cfg
.termtype
);
2868 ssh2_pkt_adduint32(cols
);
2869 ssh2_pkt_adduint32(rows
);
2870 ssh2_pkt_adduint32(0); /* pixel width */
2871 ssh2_pkt_adduint32(0); /* pixel height */
2872 ssh2_pkt_addstring_start();
2873 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2875 ssh_state
= SSH_STATE_INTERMED
;
2878 crWaitUntilV(ispkt
);
2879 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2880 unsigned i
= ssh2_pkt_getuint32();
2881 struct ssh_channel
*c
;
2882 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2884 continue; /* nonexistent channel */
2885 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2887 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2889 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2890 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2891 bombout(("Server got confused by pty request"));
2894 c_write("Server refused to allocate pty\r\n", 32);
2895 ssh_editing
= ssh_echoing
= 1;
2897 logevent("Allocated pty");
2900 ssh_editing
= ssh_echoing
= 1;
2904 * Start a shell or a remote command.
2906 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2907 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2908 if (cfg
.ssh_subsys
) {
2909 ssh2_pkt_addstring("subsystem");
2910 ssh2_pkt_addbool(1); /* want reply */
2911 ssh2_pkt_addstring(cfg
.remote_cmd
);
2912 } else if (*cfg
.remote_cmd
) {
2913 ssh2_pkt_addstring("exec");
2914 ssh2_pkt_addbool(1); /* want reply */
2915 ssh2_pkt_addstring(cfg
.remote_cmd
);
2917 ssh2_pkt_addstring("shell");
2918 ssh2_pkt_addbool(1); /* want reply */
2922 crWaitUntilV(ispkt
);
2923 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2924 unsigned i
= ssh2_pkt_getuint32();
2925 struct ssh_channel
*c
;
2926 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2928 continue; /* nonexistent channel */
2929 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2931 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2932 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2933 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2934 bombout(("Server got confused by shell/command request"));
2937 bombout(("Server refused to start a shell/command"));
2940 logevent("Started a shell/command");
2943 ssh_state
= SSH_STATE_SESSION
;
2947 ssh_special(TS_EOF
);
2952 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2955 static int try_send
;
2959 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2960 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2963 unsigned i
= ssh2_pkt_getuint32();
2964 struct ssh_channel
*c
;
2965 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2967 continue; /* nonexistent channel */
2968 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2969 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2970 continue; /* extended but not stderr */
2971 ssh2_pkt_getstring(&data
, &length
);
2974 case CHAN_MAINSESSION
:
2975 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
2979 x11_send(c
->u
.x11
.s
, data
, length
);
2983 * Enlarge the window again at the remote
2984 * side, just in case it ever runs down and
2985 * they fail to send us any more data.
2987 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2988 ssh2_pkt_adduint32(c
->remoteid
);
2989 ssh2_pkt_adduint32(length
);
2992 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
2993 ssh_state
= SSH_STATE_CLOSED
;
2994 logevent("Received disconnect message");
2996 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
2997 continue; /* exit status et al; ignore (FIXME?) */
2998 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
2999 unsigned i
= ssh2_pkt_getuint32();
3000 struct ssh_channel
*c
;
3002 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3004 continue; /* nonexistent channel */
3006 if (c
->type
== CHAN_X11
) {
3008 * Remote EOF on an X11 channel means we should
3009 * wrap up and close the channel ourselves.
3011 x11_close(c
->u
.x11
.s
);
3014 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
3015 unsigned i
= ssh2_pkt_getuint32();
3016 struct ssh_channel
*c
;
3019 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3021 continue; /* nonexistent channel */
3022 if (c
->closes
== 0) {
3023 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3024 ssh2_pkt_adduint32(c
->remoteid
);
3027 /* Do pre-close processing on the channel. */
3029 case CHAN_MAINSESSION
:
3030 break; /* nothing to see here, move along */
3034 del234(ssh_channels
, c
);
3035 sfree(c
->v2
.outbuffer
);
3039 * See if that was the last channel left open.
3041 c
= first234(ssh_channels
, &e
);
3043 logevent("All channels closed. Disconnecting");
3044 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3045 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3046 ssh2_pkt_addstring("All open channels closed");
3047 ssh2_pkt_addstring("en"); /* language tag */
3049 ssh_state
= SSH_STATE_CLOSED
;
3052 continue; /* remote sends close; ignore (FIXME) */
3053 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3054 unsigned i
= ssh2_pkt_getuint32();
3055 struct ssh_channel
*c
;
3056 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3058 continue; /* nonexistent channel */
3059 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3061 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3065 struct ssh_channel
*c
;
3066 ssh2_pkt_getstring(&type
, &typelen
);
3067 c
= smalloc(sizeof(struct ssh_channel
));
3069 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3070 if (!ssh_X11_fwd_enabled
)
3071 error
= "X11 forwarding is not enabled";
3072 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3073 error
= "Unable to open an X11 connection";
3078 error
= "Unsupported channel type requested";
3081 c
->remoteid
= ssh2_pkt_getuint32();
3083 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3084 ssh2_pkt_adduint32(c
->remoteid
);
3085 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3086 ssh2_pkt_addstring(error
);
3087 ssh2_pkt_addstring("en"); /* language tag */
3091 struct ssh_channel
*d
;
3095 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3098 break; /* found a free number */
3103 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3104 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3105 c
->v2
.outbuffer
= NULL
;
3106 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3107 add234(ssh_channels
, c
);
3108 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3109 ssh2_pkt_adduint32(c
->remoteid
);
3110 ssh2_pkt_adduint32(c
->localid
);
3111 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3112 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3116 bombout(("Strange packet received: type %d", pktin
.type
));
3121 * We have spare data. Add it to the channel buffer.
3123 ssh2_add_channel_data(mainchan
, in
, inlen
);
3128 struct ssh_channel
*c
;
3130 * Try to send data on all channels if we can.
3132 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3141 * Handle the top-level SSH2 protocol.
3143 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3145 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3147 do_ssh2_authconn(in
, inlen
, ispkt
);
3151 * Called to set up the connection.
3153 * Returns an error message, or NULL on success.
3155 static char *ssh_init (char *host
, int port
, char **realhost
) {
3159 if(crypto_startup() == 0)
3160 return "Microsoft high encryption pack not installed!";
3167 p
= connect_to_host(host
, port
, realhost
);
3175 * Called to send data down the Telnet connection.
3177 static void ssh_send (char *buf
, int len
) {
3178 if (s
== NULL
|| ssh_protocol
== NULL
)
3181 ssh_protocol(buf
, len
, 0);
3185 * Called to set the size of the window from SSH's POV.
3187 static void ssh_size(void) {
3188 switch (ssh_state
) {
3189 case SSH_STATE_BEFORE_SIZE
:
3190 case SSH_STATE_PREPACKET
:
3191 case SSH_STATE_CLOSED
:
3192 break; /* do nothing */
3193 case SSH_STATE_INTERMED
:
3194 size_needed
= TRUE
; /* buffer for later */
3196 case SSH_STATE_SESSION
:
3198 if (ssh_version
== 1) {
3199 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3200 PKT_INT
, rows
, PKT_INT
, cols
,
3201 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3203 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3204 ssh2_pkt_adduint32(mainchan
->remoteid
);
3205 ssh2_pkt_addstring("window-change");
3206 ssh2_pkt_addbool(0);
3207 ssh2_pkt_adduint32(cols
);
3208 ssh2_pkt_adduint32(rows
);
3209 ssh2_pkt_adduint32(0);
3210 ssh2_pkt_adduint32(0);
3219 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3220 * can send an EOF and collect resulting output (e.g. `plink
3223 static void ssh_special (Telnet_Special code
) {
3224 if (code
== TS_EOF
) {
3225 if (ssh_state
!= SSH_STATE_SESSION
) {
3227 * Buffer the EOF in case we are pre-SESSION, so we can
3228 * send it as soon as we reach SESSION.
3234 if (ssh_version
== 1) {
3235 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3237 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3238 ssh2_pkt_adduint32(mainchan
->remoteid
);
3241 logevent("Sent EOF message");
3242 } else if (code
== TS_PING
) {
3243 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3245 if (ssh_version
== 1) {
3246 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3248 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3249 ssh2_pkt_addstring_start();
3257 static Socket
ssh_socket(void) { return s
; }
3259 static int ssh_sendok(void) { return ssh_send_ok
; }
3261 static int ssh_ldisc(int option
) {
3262 if (option
== LD_ECHO
) return ssh_echoing
;
3263 if (option
== LD_EDIT
) return ssh_editing
;
3267 Backend ssh_backend
= {