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 ssh2_ciphers ssh2_3des
;
169 extern const struct ssh_cipher ssh_des
;
170 extern const struct ssh2_ciphers ssh2_aes
;
171 extern const struct ssh_cipher ssh_blowfish_ssh1
;
172 extern const struct ssh2_ciphers ssh2_blowfish
;
174 extern char *x11_init (Socket
*, char *, void *);
175 extern void x11_close (Socket
);
176 extern void x11_send (Socket
, char *, int);
177 extern void x11_invent_auth(char *, int, char *, int);
180 * Ciphers for SSH2. We miss out single-DES because it isn't
181 * supported; also 3DES and Blowfish are both done differently from
182 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
183 * endianness and different-sized keys.)
185 const static struct ssh2_ciphers
*ciphers
[] = {
191 extern const struct ssh_kex ssh_diffiehellman
;
192 extern const struct ssh_kex ssh_diffiehellman_gex
;
193 const static struct ssh_kex
*kex_algs
[] = {
194 #ifdef DO_DIFFIE_HELLMAN_GEX
195 &ssh_diffiehellman_gex
,
197 &ssh_diffiehellman
};
199 extern const struct ssh_signkey ssh_dss
;
200 extern const struct ssh_signkey ssh_rsa
;
201 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
203 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
205 static void nullmac_key(unsigned char *key
) { }
206 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
207 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
208 const static struct ssh_mac ssh_mac_none
= {
209 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
211 const static struct ssh_mac
*macs
[] = {
212 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
213 const static struct ssh_mac
*buggymacs
[] = {
214 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
216 static void ssh_comp_none_init(void) { }
217 static int ssh_comp_none_block(unsigned char *block
, int len
,
218 unsigned char **outblock
, int *outlen
) {
221 const static struct ssh_compress ssh_comp_none
= {
223 ssh_comp_none_init
, ssh_comp_none_block
,
224 ssh_comp_none_init
, ssh_comp_none_block
226 extern const struct ssh_compress ssh_zlib
;
227 const static struct ssh_compress
*compressions
[] = {
228 &ssh_zlib
, &ssh_comp_none
};
230 enum { /* channel types */
237 * 2-3-4 tree storing channels.
240 unsigned remoteid
, localid
;
243 struct ssh2_data_channel
{
244 unsigned char *outbuffer
;
245 unsigned outbuflen
, outbufsize
;
246 unsigned remwindow
, remmaxpkt
;
249 struct ssh_agent_channel
{
250 unsigned char *message
;
251 unsigned char msglen
[4];
252 int lensofar
, totallen
;
254 struct ssh_x11_channel
{
269 static SHA_State exhash
, exhashbase
;
271 static Socket s
= NULL
;
273 static unsigned char session_key
[32];
274 static int ssh1_compressing
;
275 static int ssh_agentfwd_enabled
;
276 static int ssh_X11_fwd_enabled
;
277 static const struct ssh_cipher
*cipher
= NULL
;
278 static const struct ssh2_cipher
*cscipher
= NULL
;
279 static const struct ssh2_cipher
*sccipher
= NULL
;
280 static const struct ssh_mac
*csmac
= NULL
;
281 static const struct ssh_mac
*scmac
= NULL
;
282 static const struct ssh_compress
*cscomp
= NULL
;
283 static const struct ssh_compress
*sccomp
= NULL
;
284 static const struct ssh_kex
*kex
= NULL
;
285 static const struct ssh_signkey
*hostkey
= NULL
;
286 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
288 static char *savedhost
;
289 static int savedport
;
290 static int ssh_send_ok
;
291 static int ssh_echoing
, ssh_editing
;
293 static tree234
*ssh_channels
; /* indexed by local id */
294 static struct ssh_channel
*mainchan
; /* primary session channel */
298 SSH_STATE_BEFORE_SIZE
,
302 } ssh_state
= SSH_STATE_PREPACKET
;
304 static int size_needed
= FALSE
, eof_needed
= FALSE
;
306 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
307 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
308 static unsigned char *deferred_send_data
= NULL
;
309 static int deferred_len
= 0, deferred_size
= 0;
311 static int ssh_version
;
312 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
313 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
314 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
315 static void ssh_size(void);
316 static void ssh_special (Telnet_Special
);
317 static void ssh2_try_send(struct ssh_channel
*c
);
318 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
320 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
322 static struct rdpkt1_state_tag
{
323 long len
, pad
, biglen
, to_read
;
324 unsigned long realcrc
, gotcrc
;
330 static struct rdpkt2_state_tag
{
331 long len
, pad
, payload
, packetlen
, maclen
;
334 unsigned long incoming_sequence
;
337 static int ssh_channelcmp(void *av
, void *bv
) {
338 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
339 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
340 if (a
->localid
< b
->localid
) return -1;
341 if (a
->localid
> b
->localid
) return +1;
344 static int ssh_channelfind(void *av
, void *bv
) {
345 unsigned *a
= (unsigned *)av
;
346 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
347 if (*a
< b
->localid
) return -1;
348 if (*a
> b
->localid
) return +1;
352 static void c_write (char *buf
, int len
) {
353 if ((flags
& FLAG_STDERR
)) {
355 for (i
= 0; i
< len
; i
++)
357 fputc(buf
[i
], stderr
);
360 from_backend(1, buf
, len
);
364 * Collect incoming data in the incoming packet buffer.
365 * Decipher and verify the packet when it is completely read.
366 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
367 * Update the *data and *datalen variables.
368 * Return the additional nr of bytes needed, or 0 when
369 * a complete packet is available.
371 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
373 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
382 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
383 while ((*datalen
) == 0)
385 st
->len
= (st
->len
<< 8) + **data
;
386 (*data
)++, (*datalen
)--;
390 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
391 st
->len
= 0x300; /* big enough to carry to end */
395 st
->pad
= 8 - (st
->len
% 8);
396 st
->biglen
= st
->len
+ st
->pad
;
397 pktin
.length
= st
->len
- 5;
399 if (pktin
.maxlen
< st
->biglen
) {
400 pktin
.maxlen
= st
->biglen
;
401 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
402 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
404 fatalbox("Out of memory");
407 st
->to_read
= st
->biglen
;
409 while (st
->to_read
> 0) {
410 st
->chunk
= st
->to_read
;
411 while ((*datalen
) == 0)
412 crReturn(st
->to_read
);
413 if (st
->chunk
> (*datalen
))
414 st
->chunk
= (*datalen
);
415 memcpy(st
->p
, *data
, st
->chunk
);
417 *datalen
-= st
->chunk
;
419 st
->to_read
-= st
->chunk
;
423 cipher
->decrypt(pktin
.data
, st
->biglen
);
425 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
426 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
427 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
431 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
432 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
433 if (st
->gotcrc
!= st
->realcrc
) {
434 bombout(("Incorrect CRC received on packet"));
438 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
440 if (ssh1_compressing
) {
441 unsigned char *decompblk
;
445 debug(("Packet payload pre-decompression:\n"));
446 for (i
= -1; i
< pktin
.length
; i
++)
447 debug((" %02x", (unsigned char)pktin
.body
[i
]));
450 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
451 &decompblk
, &decomplen
);
453 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
454 pktin
.maxlen
= st
->pad
+ decomplen
;
455 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
456 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
458 fatalbox("Out of memory");
461 memcpy(pktin
.body
-1, decompblk
, decomplen
);
463 pktin
.length
= decomplen
-1;
465 debug(("Packet payload post-decompression:\n"));
466 for (i
= -1; i
< pktin
.length
; i
++)
467 debug((" %02x", (unsigned char)pktin
.body
[i
]));
472 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
473 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
474 pktin
.type
== SSH1_MSG_DEBUG
||
475 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
476 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
477 long strlen
= GET_32BIT(pktin
.body
);
478 if (strlen
+ 4 != pktin
.length
) {
479 bombout(("Received data packet with bogus string length"));
484 pktin
.type
= pktin
.body
[-1];
486 if (pktin
.type
== SSH1_MSG_DEBUG
) {
487 /* log debug message */
489 int strlen
= GET_32BIT(pktin
.body
);
490 strcpy(buf
, "Remote: ");
491 if (strlen
> 70) strlen
= 70;
492 memcpy(buf
+8, pktin
.body
+4, strlen
);
493 buf
[8+strlen
] = '\0';
496 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
504 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
506 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
514 st
->cipherblk
= sccipher
->blksize
;
517 if (st
->cipherblk
< 8)
520 if (pktin
.maxlen
< st
->cipherblk
) {
521 pktin
.maxlen
= st
->cipherblk
;
522 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
523 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
525 fatalbox("Out of memory");
529 * Acquire and decrypt the first block of the packet. This will
530 * contain the length and padding details.
532 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
533 while ((*datalen
) == 0)
534 crReturn(st
->cipherblk
-st
->i
);
535 pktin
.data
[st
->i
] = *(*data
)++;
539 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
544 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
547 * Now get the length and padding figures.
549 st
->len
= GET_32BIT(pktin
.data
);
550 st
->pad
= pktin
.data
[4];
553 * This enables us to deduce the payload length.
555 st
->payload
= st
->len
- st
->pad
- 1;
557 pktin
.length
= st
->payload
+ 5;
560 * So now we can work out the total packet length.
562 st
->packetlen
= st
->len
+ 4;
563 st
->maclen
= scmac ? scmac
->len
: 0;
566 * Adjust memory allocation if packet is too big.
568 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
569 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
570 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
571 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
573 fatalbox("Out of memory");
577 * Read and decrypt the remainder of the packet.
579 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
580 while ((*datalen
) == 0)
581 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
582 pktin
.data
[st
->i
] = *(*data
)++;
585 /* Decrypt everything _except_ the MAC. */
587 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
588 st
->packetlen
- st
->cipherblk
);
591 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
592 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
593 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
600 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
601 bombout(("Incorrect MAC received on packet"));
604 st
->incoming_sequence
++; /* whether or not we MACed */
607 * Decompress packet payload.
610 unsigned char *newpayload
;
612 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
613 &newpayload
, &newlen
)) {
614 if (pktin
.maxlen
< newlen
+5) {
615 pktin
.maxlen
= newlen
+5;
616 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
617 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
619 fatalbox("Out of memory");
621 pktin
.length
= 5 + newlen
;
622 memcpy(pktin
.data
+5, newpayload
, newlen
);
624 debug(("Post-decompression payload:\r\n"));
625 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
626 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
635 pktin
.type
= pktin
.data
[5];
637 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
638 goto next_packet
; /* FIXME: print DEBUG message */
643 static void ssh1_pktout_size(int len
) {
646 len
+= 5; /* type and CRC */
650 pktout
.length
= len
-5;
651 if (pktout
.maxlen
< biglen
) {
652 pktout
.maxlen
= biglen
;
654 /* Allocate enough buffer space for extra block
655 * for MS CryptEncrypt() */
656 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
657 srealloc(pktout
.data
, biglen
+12));
659 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
660 srealloc(pktout
.data
, biglen
+4));
663 fatalbox("Out of memory");
665 pktout
.body
= pktout
.data
+4+pad
+1;
668 static void s_wrpkt_start(int type
, int len
) {
669 ssh1_pktout_size(len
);
673 static void s_wrpkt(void) {
674 int pad
, len
, biglen
, i
;
677 pktout
.body
[-1] = pktout
.type
;
679 if (ssh1_compressing
) {
680 unsigned char *compblk
;
683 debug(("Packet payload pre-compression:\n"));
684 for (i
= -1; i
< pktout
.length
; i
++)
685 debug((" %02x", (unsigned char)pktout
.body
[i
]));
688 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
690 ssh1_pktout_size(complen
-1);
691 memcpy(pktout
.body
-1, compblk
, complen
);
694 debug(("Packet payload post-compression:\n"));
695 for (i
= -1; i
< pktout
.length
; i
++)
696 debug((" %02x", (unsigned char)pktout
.body
[i
]));
701 len
= pktout
.length
+ 5; /* type and CRC */
705 for (i
=0; i
<pad
; i
++)
706 pktout
.data
[i
+4] = random_byte();
707 crc
= crc32(pktout
.data
+4, biglen
-4);
708 PUT_32BIT(pktout
.data
+biglen
, crc
);
709 PUT_32BIT(pktout
.data
, len
);
712 debug(("Sending packet len=%d\r\n", biglen
+4));
713 for (i
= 0; i
< biglen
+4; i
++)
714 debug((" %02x", (unsigned char)pktout
.data
[i
]));
718 cipher
->encrypt(pktout
.data
+4, biglen
);
720 sk_write(s
, pktout
.data
, biglen
+4);
724 * Construct a packet with the specified contents and
725 * send it to the server.
727 static void send_packet(int pkttype
, ...)
730 unsigned char *p
, *argp
, argchar
;
731 unsigned long argint
;
732 int pktlen
, argtype
, arglen
;
736 va_start(args
, pkttype
);
737 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
740 (void) va_arg(args
, int);
744 (void) va_arg(args
, char);
748 (void) va_arg(args
, unsigned char *);
749 arglen
= va_arg(args
, int);
753 argp
= va_arg(args
, unsigned char *);
754 arglen
= strlen(argp
);
755 pktlen
+= 4 + arglen
;
758 bn
= va_arg(args
, Bignum
);
759 pktlen
+= ssh1_bignum_length(bn
);
767 s_wrpkt_start(pkttype
, pktlen
);
770 va_start(args
, pkttype
);
771 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
774 argint
= va_arg(args
, int);
775 PUT_32BIT(p
, argint
);
779 argchar
= va_arg(args
, unsigned char);
784 argp
= va_arg(args
, unsigned char *);
785 arglen
= va_arg(args
, int);
786 memcpy(p
, argp
, arglen
);
790 argp
= va_arg(args
, unsigned char *);
791 arglen
= strlen(argp
);
792 PUT_32BIT(p
, arglen
);
793 memcpy(p
+ 4, argp
, arglen
);
797 bn
= va_arg(args
, Bignum
);
798 p
+= ssh1_write_bignum(p
, bn
);
807 static int ssh_versioncmp(char *a
, char *b
) {
809 unsigned long av
, bv
;
811 av
= strtoul(a
, &ae
, 10);
812 bv
= strtoul(b
, &be
, 10);
813 if (av
!= bv
) return (av
< bv ?
-1 : +1);
814 if (*ae
== '.') ae
++;
815 if (*be
== '.') be
++;
816 av
= strtoul(ae
, &ae
, 10);
817 bv
= strtoul(be
, &be
, 10);
818 if (av
!= bv
) return (av
< bv ?
-1 : +1);
824 * Utility routines for putting an SSH-protocol `string' and
825 * `uint32' into a SHA state.
828 static void sha_string(SHA_State
*s
, void *str
, int len
) {
829 unsigned char lenblk
[4];
830 PUT_32BIT(lenblk
, len
);
831 SHA_Bytes(s
, lenblk
, 4);
832 SHA_Bytes(s
, str
, len
);
835 static void sha_uint32(SHA_State
*s
, unsigned i
) {
836 unsigned char intblk
[4];
837 PUT_32BIT(intblk
, i
);
838 SHA_Bytes(s
, intblk
, 4);
842 * SSH2 packet construction functions.
844 static void ssh2_pkt_ensure(int length
) {
845 if (pktout
.maxlen
< length
) {
846 pktout
.maxlen
= length
+ 256;
847 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
848 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
850 fatalbox("Out of memory");
853 static void ssh2_pkt_adddata(void *data
, int len
) {
854 pktout
.length
+= len
;
855 ssh2_pkt_ensure(pktout
.length
);
856 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
858 static void ssh2_pkt_addbyte(unsigned char byte
) {
859 ssh2_pkt_adddata(&byte
, 1);
861 static void ssh2_pkt_init(int pkt_type
) {
863 ssh2_pkt_addbyte((unsigned char)pkt_type
);
865 static void ssh2_pkt_addbool(unsigned char value
) {
866 ssh2_pkt_adddata(&value
, 1);
868 static void ssh2_pkt_adduint32(unsigned long value
) {
871 ssh2_pkt_adddata(x
, 4);
873 static void ssh2_pkt_addstring_start(void) {
874 ssh2_pkt_adduint32(0);
875 pktout
.savedpos
= pktout
.length
;
877 static void ssh2_pkt_addstring_str(char *data
) {
878 ssh2_pkt_adddata(data
, strlen(data
));
879 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
880 pktout
.length
- pktout
.savedpos
);
882 static void ssh2_pkt_addstring_data(char *data
, int len
) {
883 ssh2_pkt_adddata(data
, len
);
884 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
885 pktout
.length
- pktout
.savedpos
);
887 static void ssh2_pkt_addstring(char *data
) {
888 ssh2_pkt_addstring_start();
889 ssh2_pkt_addstring_str(data
);
891 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
893 int i
, n
= (ssh1_bignum_bitcount(b
)+7)/8;
896 fatalbox("out of memory");
898 for (i
= 1; i
<= n
; i
++)
899 p
[i
] = bignum_byte(b
, n
-i
);
901 while (i
<= n
&& p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
903 memmove(p
, p
+i
, n
+1-i
);
907 static void ssh2_pkt_addmp(Bignum b
) {
910 p
= ssh2_mpint_fmt(b
, &len
);
911 ssh2_pkt_addstring_start();
912 ssh2_pkt_addstring_data(p
, len
);
917 * Construct an SSH2 final-form packet: compress it, encrypt it,
918 * put the MAC on it. Final packet, ready to be sent, is stored in
919 * pktout.data. Total length is returned.
921 static int ssh2_pkt_construct(void) {
922 int cipherblk
, maclen
, padding
, i
;
923 static unsigned long outgoing_sequence
= 0;
926 * Compress packet payload.
929 debug(("Pre-compression payload:\r\n"));
930 for (i
= 5; i
< pktout
.length
; i
++)
931 debug((" %02x", (unsigned char)pktout
.data
[i
]));
935 unsigned char *newpayload
;
937 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
938 &newpayload
, &newlen
)) {
940 ssh2_pkt_adddata(newpayload
, newlen
);
946 * Add padding. At least four bytes, and must also bring total
947 * length (minus MAC) up to a multiple of the block size.
949 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
950 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
952 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
953 maclen
= csmac ? csmac
->len
: 0;
954 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
955 pktout
.data
[4] = padding
;
956 for (i
= 0; i
< padding
; i
++)
957 pktout
.data
[pktout
.length
+ i
] = random_byte();
958 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
960 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
962 outgoing_sequence
++; /* whether or not we MACed */
965 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
966 for (i
= 0; i
< pktout
.length
+padding
; i
++)
967 debug((" %02x", (unsigned char)pktout
.data
[i
]));
972 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
974 /* Ready-to-send packet starts at pktout.data. We return length. */
975 return pktout
.length
+ padding
+ maclen
;
979 * Construct and send an SSH2 packet immediately.
981 static void ssh2_pkt_send(void) {
982 int len
= ssh2_pkt_construct();
983 sk_write(s
, pktout
.data
, len
);
987 * Construct an SSH2 packet and add it to a deferred data block.
988 * Useful for sending multiple packets in a single sk_write() call,
989 * to prevent a traffic-analysing listener from being able to work
990 * out the length of any particular packet (such as the password
993 * Note that because SSH2 sequence-numbers its packets, this can
994 * NOT be used as an m4-style `defer' allowing packets to be
995 * constructed in one order and sent in another.
997 static void ssh2_pkt_defer(void) {
998 int len
= ssh2_pkt_construct();
999 if (deferred_len
+ len
> deferred_size
) {
1000 deferred_size
= deferred_len
+ len
+ 128;
1001 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1003 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
1004 deferred_len
+= len
;
1008 * Send the whole deferred data block constructed by
1011 static void ssh2_pkt_defersend(void) {
1012 sk_write(s
, deferred_send_data
, deferred_len
);
1013 deferred_len
= deferred_size
= 0;
1014 sfree(deferred_send_data
);
1015 deferred_send_data
= NULL
;
1019 void bndebug(char *string
, Bignum b
) {
1022 p
= ssh2_mpint_fmt(b
, &len
);
1023 debug(("%s", string
));
1024 for (i
= 0; i
< len
; i
++)
1025 debug((" %02x", p
[i
]));
1031 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1034 p
= ssh2_mpint_fmt(b
, &len
);
1035 sha_string(s
, p
, len
);
1040 * SSH2 packet decode functions.
1042 static unsigned long ssh2_pkt_getuint32(void) {
1043 unsigned long value
;
1044 if (pktin
.length
- pktin
.savedpos
< 4)
1045 return 0; /* arrgh, no way to decline (FIXME?) */
1046 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1047 pktin
.savedpos
+= 4;
1050 static void ssh2_pkt_getstring(char **p
, int *length
) {
1052 if (pktin
.length
- pktin
.savedpos
< 4)
1054 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1055 pktin
.savedpos
+= 4;
1056 if (pktin
.length
- pktin
.savedpos
< *length
)
1058 *p
= pktin
.data
+pktin
.savedpos
;
1059 pktin
.savedpos
+= *length
;
1061 static Bignum
ssh2_pkt_getmp(void) {
1066 ssh2_pkt_getstring(&p
, &length
);
1070 bombout(("internal error: Can't handle negative mpints"));
1073 b
= bignum_from_bytes(p
, length
);
1077 static int do_ssh_init(unsigned char c
) {
1079 static char version
[10];
1080 static char vstring
[80];
1081 static char vlog
[sizeof(vstring
)+20];
1086 /* Search for the string "SSH-" in the input. */
1089 static const int transS
[] = { 1, 2, 2, 1 };
1090 static const int transH
[] = { 0, 0, 3, 0 };
1091 static const int transminus
[] = { 0, 0, 0, -1 };
1092 if (c
== 'S') i
= transS
[i
];
1093 else if (c
== 'H') i
= transH
[i
];
1094 else if (c
== '-') i
= transminus
[i
];
1098 crReturn(1); /* get another character */
1101 strcpy(vstring
, "SSH-");
1105 crReturn(1); /* get another char */
1106 if (vsp
< vstring
+sizeof(vstring
)-1)
1112 } else if (i
< sizeof(version
)-1)
1119 ssh_agentfwd_enabled
= FALSE
;
1120 rdpkt2_state
.incoming_sequence
= 0;
1123 sprintf(vlog
, "Server version: %s", vstring
);
1124 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1128 * Server version "1.99" means we can choose whether we use v1
1129 * or v2 protocol. Choice is based on cfg.sshprot.
1131 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1133 * This is a v2 server. Begin v2 protocol.
1135 char *verstring
= "SSH-2.0-PuTTY";
1136 SHA_Init(&exhashbase
);
1138 * Hash our version string and their version string.
1140 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1141 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1142 sprintf(vstring
, "%s\n", verstring
);
1143 sprintf(vlog
, "We claim version: %s", verstring
);
1145 logevent("Using SSH protocol version 2");
1146 sk_write(s
, vstring
, strlen(vstring
));
1147 ssh_protocol
= ssh2_protocol
;
1149 s_rdpkt
= ssh2_rdpkt
;
1152 * This is a v1 server. Begin v1 protocol.
1154 sprintf(vstring
, "SSH-%s-PuTTY\n",
1155 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1156 sprintf(vlog
, "We claim version: %s", vstring
);
1157 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1159 logevent("Using SSH protocol version 1");
1160 sk_write(s
, vstring
, strlen(vstring
));
1161 ssh_protocol
= ssh1_protocol
;
1163 s_rdpkt
= ssh1_rdpkt
;
1165 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1170 static void ssh_gotdata(unsigned char *data
, int datalen
)
1175 * To begin with, feed the characters one by one to the
1176 * protocol initialisation / selection function do_ssh_init().
1177 * When that returns 0, we're done with the initial greeting
1178 * exchange and can move on to packet discipline.
1183 crReturnV
; /* more data please */
1184 ret
= do_ssh_init(*data
);
1191 * We emerge from that loop when the initial negotiation is
1192 * over and we have selected an s_rdpkt function. Now pass
1193 * everything to s_rdpkt, and then pass the resulting packets
1194 * to the proper protocol handler.
1199 while (datalen
> 0) {
1200 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1201 ssh_protocol(NULL
, 0, 1);
1202 if (ssh_state
== SSH_STATE_CLOSED
) {
1212 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1214 /* A socket error has occurred. */
1215 ssh_state
= SSH_STATE_CLOSED
;
1218 connection_fatal(data
);
1221 /* Connection has closed. */
1222 ssh_state
= SSH_STATE_CLOSED
;
1227 ssh_gotdata (data
, len
);
1228 if (ssh_state
== SSH_STATE_CLOSED
) {
1239 * Connect to specified host and port.
1240 * Returns an error message, or NULL on success.
1241 * Also places the canonical host name into `realhost'.
1243 static char *connect_to_host(char *host
, int port
, char **realhost
)
1252 savedhost
= smalloc(1+strlen(host
));
1254 fatalbox("Out of memory");
1255 strcpy(savedhost
, host
);
1258 port
= 22; /* default ssh port */
1271 addr
= sk_namelookup(host
, realhost
);
1272 if ( (err
= sk_addr_error(addr
)) )
1282 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1283 if ( (err
= sk_socket_error(s
)) )
1287 sk_write(s
, "connect ", 8);
1288 sk_write(s
, FWhost
, strlen(FWhost
));
1291 sprintf(buf
, " %d\n", FWport
);
1292 sk_write(s
, buf
, strlen(buf
));
1300 * Handle the key exchange and user authentication phases.
1302 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1305 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1306 unsigned char cookie
[8];
1307 struct RSAKey servkey
, hostkey
;
1308 struct MD5Context md5c
;
1309 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1310 static int tried_publickey
;
1311 static unsigned char session_id
[16];
1313 static char username
[100];
1317 if (!ispkt
) crWaitUntil(ispkt
);
1319 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1320 bombout(("Public key packet not received"));
1324 logevent("Received public keys");
1326 memcpy(cookie
, pktin
.body
, 8);
1328 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1329 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1332 * Log the host key fingerprint.
1336 logevent("Host key fingerprint is:");
1337 strcpy(logmsg
, " ");
1338 hostkey
.comment
= NULL
;
1339 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1344 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1345 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1348 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1349 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1350 MD5Update(&md5c
, pktin
.body
, 8);
1351 MD5Final(session_id
, &md5c
);
1353 for (i
=0; i
<32; i
++)
1354 session_key
[i
] = random_byte();
1356 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1358 rsabuf
= smalloc(len
);
1360 fatalbox("Out of memory");
1363 * Verify the host key.
1367 * First format the key into a string.
1369 int len
= rsastr_len(&hostkey
);
1370 char fingerprint
[100];
1371 char *keystr
= smalloc(len
);
1373 fatalbox("Out of memory");
1374 rsastr_fmt(keystr
, &hostkey
);
1375 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1376 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1380 for (i
=0; i
<32; i
++) {
1381 rsabuf
[i
] = session_key
[i
];
1383 rsabuf
[i
] ^= session_id
[i
];
1386 if (hostkey
.bytes
> servkey
.bytes
) {
1387 rsaencrypt(rsabuf
, 32, &servkey
);
1388 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1390 rsaencrypt(rsabuf
, 32, &hostkey
);
1391 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1394 logevent("Encrypted session key");
1396 switch (cfg
.cipher
) {
1397 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
; break;
1398 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
; break;
1399 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
; break;
1401 c_write("AES not supported in SSH1, falling back to 3DES\r\n", 49);
1402 cipher_type
= SSH_CIPHER_3DES
;
1405 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1406 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1407 cipher_type
= SSH_CIPHER_3DES
;
1409 switch (cipher_type
) {
1410 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1411 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1412 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1415 send_packet(SSH1_CMSG_SESSION_KEY
,
1416 PKT_CHAR
, cipher_type
,
1417 PKT_DATA
, cookie
, 8,
1418 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1419 PKT_DATA
, rsabuf
, len
,
1423 logevent("Trying to enable encryption...");
1427 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1428 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1430 cipher
->sesskey(session_key
);
1434 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1435 bombout(("Encryption not successfully enabled"));
1439 logevent("Successfully started encryption");
1445 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1446 c_write("login as: ", 10);
1449 crWaitUntil(!ispkt
);
1450 while (inlen
--) switch (c
= *in
++) {
1457 c_write("\b \b", 3);
1463 c_write("\b \b", 3);
1472 if (((c
>= ' ' && c
<= '~') ||
1473 ((unsigned char)c
>= 160)) && pos
< 40) {
1474 username
[pos
++] = c
;
1481 username
[strcspn(username
, "\n\r")] = '\0';
1483 strncpy(username
, cfg
.username
, 99);
1484 username
[99] = '\0';
1487 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1489 char userlog
[22+sizeof(username
)];
1490 sprintf(userlog
, "Sent username \"%s\"", username
);
1492 if (flags
& FLAG_INTERACTIVE
&&
1493 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1494 strcat(userlog
, "\r\n");
1495 c_write(userlog
, strlen(userlog
));
1502 tried_publickey
= 0;
1504 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1505 static char password
[100];
1506 static char prompt
[200];
1509 static int pwpkt_type
;
1511 * Show password prompt, having first obtained it via a TIS
1512 * or CryptoCard exchange if we're doing TIS or CryptoCard
1515 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1516 if (agent_exists()) {
1518 * Attempt RSA authentication using Pageant.
1520 static unsigned char request
[5], *response
, *p
;
1521 static int responselen
;
1522 static int i
, nkeys
;
1523 static int authed
= FALSE
;
1526 logevent("Pageant is running. Requesting keys.");
1528 /* Request the keys held by the agent. */
1529 PUT_32BIT(request
, 1);
1530 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1531 agent_query(request
, 5, &r
, &responselen
);
1532 response
= (unsigned char *)r
;
1535 nkeys
= GET_32BIT(p
); p
+= 4;
1536 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1538 for (i
= 0; i
< nkeys
; i
++) {
1539 static struct RSAKey key
;
1540 static Bignum challenge
;
1541 static char *commentp
;
1542 static int commentlen
;
1544 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1547 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1548 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1549 commentlen
= GET_32BIT(p
); p
+= 4;
1550 commentp
= p
; p
+= commentlen
;
1551 send_packet(SSH1_CMSG_AUTH_RSA
,
1552 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1554 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1555 logevent("Key refused");
1558 logevent("Received RSA challenge");
1559 ssh1_read_bignum(pktin
.body
, &challenge
);
1561 char *agentreq
, *q
, *ret
;
1563 len
= 1 + 4; /* message type, bit count */
1564 len
+= ssh1_bignum_length(key
.exponent
);
1565 len
+= ssh1_bignum_length(key
.modulus
);
1566 len
+= ssh1_bignum_length(challenge
);
1567 len
+= 16; /* session id */
1568 len
+= 4; /* response format */
1569 agentreq
= smalloc(4 + len
);
1570 PUT_32BIT(agentreq
, len
);
1572 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1573 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1575 q
+= ssh1_write_bignum(q
, key
.exponent
);
1576 q
+= ssh1_write_bignum(q
, key
.modulus
);
1577 q
+= ssh1_write_bignum(q
, challenge
);
1578 memcpy(q
, session_id
, 16); q
+= 16;
1579 PUT_32BIT(q
, 1); /* response format */
1580 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1583 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1584 logevent("Sending Pageant's response");
1585 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1586 PKT_DATA
, ret
+5, 16, PKT_END
);
1589 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1590 logevent("Pageant's response accepted");
1591 if (flags
& FLAG_VERBOSE
) {
1592 c_write("Authenticated using RSA key \"",
1594 c_write(commentp
, commentlen
);
1595 c_write("\" from agent\r\n", 14);
1599 logevent("Pageant's response not accepted");
1601 logevent("Pageant failed to answer challenge");
1605 logevent("No reply received from Pageant");
1608 freebn(key
.exponent
);
1609 freebn(key
.modulus
);
1618 if (*cfg
.keyfile
&& !tried_publickey
)
1619 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1621 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1623 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1624 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1625 logevent("Requested TIS authentication");
1626 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1628 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1629 logevent("TIS authentication declined");
1630 if (flags
& FLAG_INTERACTIVE
)
1631 c_write("TIS authentication refused.\r\n", 29);
1633 int challengelen
= ((pktin
.body
[0] << 24) |
1634 (pktin
.body
[1] << 16) |
1635 (pktin
.body
[2] << 8) |
1637 logevent("Received TIS challenge");
1638 if (challengelen
> sizeof(prompt
)-1)
1639 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1640 memcpy(prompt
, pktin
.body
+4, challengelen
);
1641 prompt
[challengelen
] = '\0';
1644 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1646 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1647 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1648 logevent("Requested CryptoCard authentication");
1649 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1651 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1652 logevent("CryptoCard authentication declined");
1653 c_write("CryptoCard authentication refused.\r\n", 29);
1655 int challengelen
= ((pktin
.body
[0] << 24) |
1656 (pktin
.body
[1] << 16) |
1657 (pktin
.body
[2] << 8) |
1659 logevent("Received CryptoCard challenge");
1660 if (challengelen
> sizeof(prompt
)-1)
1661 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1662 memcpy(prompt
, pktin
.body
+4, challengelen
);
1663 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1664 sizeof(prompt
)-challengelen
);
1665 prompt
[sizeof(prompt
)-1] = '\0';
1668 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1669 sprintf(prompt
, "%.90s@%.90s's password: ",
1670 username
, savedhost
);
1672 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1673 char *comment
= NULL
;
1674 if (flags
& FLAG_VERBOSE
)
1675 c_write("Trying public key authentication.\r\n", 35);
1676 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1677 if (flags
& FLAG_VERBOSE
)
1678 c_write("No passphrase required.\r\n", 25);
1681 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1685 if (ssh_get_password
) {
1686 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1688 * get_password failed to get a password (for
1689 * example because one was supplied on the command
1690 * line which has already failed to work).
1693 logevent("No more passwords to try");
1694 ssh_state
= SSH_STATE_CLOSED
;
1698 c_write(prompt
, strlen(prompt
));
1702 crWaitUntil(!ispkt
);
1703 while (inlen
--) switch (c
= *in
++) {
1720 if (((c
>= ' ' && c
<= '~') ||
1721 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1722 password
[pos
++] = c
;
1730 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1732 * Try public key authentication with the specified
1735 static struct RSAKey pubkey
;
1736 static Bignum challenge
, response
;
1738 static unsigned char buffer
[32];
1740 tried_publickey
= 1;
1741 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1743 c_write("Couldn't load public key from ", 30);
1744 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1745 c_write(".\r\n", 3);
1746 continue; /* go and try password */
1749 c_write("Wrong passphrase.\r\n", 19);
1750 tried_publickey
= 0;
1751 continue; /* try again */
1755 * Send a public key attempt.
1757 send_packet(SSH1_CMSG_AUTH_RSA
,
1758 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1761 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1762 c_write("Server refused our public key.\r\n", 32);
1763 continue; /* go and try password */
1765 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1766 bombout(("Bizarre response to offer of public key"));
1769 ssh1_read_bignum(pktin
.body
, &challenge
);
1770 response
= rsadecrypt(challenge
, &pubkey
);
1771 freebn(pubkey
.private_exponent
); /* burn the evidence */
1773 for (i
= 0; i
< 32; i
++) {
1774 buffer
[i
] = bignum_byte(response
, 31-i
);
1778 MD5Update(&md5c
, buffer
, 32);
1779 MD5Update(&md5c
, session_id
, 16);
1780 MD5Final(buffer
, &md5c
);
1782 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1783 PKT_DATA
, buffer
, 16, PKT_END
);
1786 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1787 if (flags
& FLAG_VERBOSE
)
1788 c_write("Failed to authenticate with our public key.\r\n",
1790 continue; /* go and try password */
1791 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1792 bombout(("Bizarre response to RSA authentication response"));
1796 break; /* we're through! */
1798 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1800 logevent("Sent password");
1801 memset(password
, 0, strlen(password
));
1803 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1804 if (flags
& FLAG_VERBOSE
)
1805 c_write("Access denied\r\n", 15);
1806 logevent("Authentication refused");
1807 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1808 logevent("Received disconnect request");
1809 ssh_state
= SSH_STATE_CLOSED
;
1811 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1812 bombout(("Strange packet received, type %d", pktin
.type
));
1817 logevent("Authentication successful");
1822 void sshfwd_close(struct ssh_channel
*c
) {
1824 if (ssh_version
== 1) {
1825 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1827 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1828 ssh2_pkt_adduint32(c
->remoteid
);
1832 if (c
->type
== CHAN_X11
) {
1834 logevent("X11 connection terminated");
1839 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1840 if (ssh_version
== 1) {
1841 send_packet(SSH1_MSG_CHANNEL_DATA
,
1842 PKT_INT
, c
->remoteid
,
1847 ssh2_add_channel_data(c
, buf
, len
);
1852 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1857 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1860 if (ssh_state
== SSH_STATE_CLOSED
)
1863 if (cfg
.agentfwd
&& agent_exists()) {
1864 logevent("Requesting agent forwarding");
1865 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1866 do { crReturnV
; } while (!ispkt
);
1867 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1868 bombout(("Protocol confusion"));
1870 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1871 logevent("Agent forwarding refused");
1873 logevent("Agent forwarding enabled");
1874 ssh_agentfwd_enabled
= TRUE
;
1878 if (cfg
.x11_forward
) {
1879 char proto
[20], data
[64];
1880 logevent("Requesting X11 forwarding");
1881 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1882 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1883 PKT_STR
, proto
, PKT_STR
, data
,
1886 do { crReturnV
; } while (!ispkt
);
1887 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1888 bombout(("Protocol confusion"));
1890 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1891 logevent("X11 forwarding refused");
1893 logevent("X11 forwarding enabled");
1894 ssh_X11_fwd_enabled
= TRUE
;
1899 send_packet(SSH1_CMSG_REQUEST_PTY
,
1900 PKT_STR
, cfg
.termtype
,
1901 PKT_INT
, rows
, PKT_INT
, cols
,
1902 PKT_INT
, 0, PKT_INT
, 0,
1905 ssh_state
= SSH_STATE_INTERMED
;
1906 do { crReturnV
; } while (!ispkt
);
1907 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1908 bombout(("Protocol confusion"));
1910 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1911 c_write("Server refused to allocate pty\r\n", 32);
1912 ssh_editing
= ssh_echoing
= 1;
1914 logevent("Allocated pty");
1916 ssh_editing
= ssh_echoing
= 1;
1919 if (cfg
.compression
) {
1920 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1921 do { crReturnV
; } while (!ispkt
);
1922 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1923 bombout(("Protocol confusion"));
1925 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1926 c_write("Server refused to compress\r\n", 32);
1928 logevent("Started compression");
1929 ssh1_compressing
= TRUE
;
1930 zlib_compress_init();
1931 zlib_decompress_init();
1934 if (*cfg
.remote_cmd
)
1935 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1937 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1938 logevent("Started session");
1940 ssh_state
= SSH_STATE_SESSION
;
1944 ssh_special(TS_EOF
);
1946 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
1948 ssh_channels
= newtree234(ssh_channelcmp
);
1952 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1953 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1954 long len
= GET_32BIT(pktin
.body
);
1955 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
1957 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1958 ssh_state
= SSH_STATE_CLOSED
;
1959 logevent("Received disconnect request");
1961 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
1962 /* Remote side is trying to open a channel to talk to our
1963 * X-Server. Give them back a local channel number. */
1965 struct ssh_channel
*c
, *d
;
1968 logevent("Received X11 connect request");
1969 /* Refuse if X11 forwarding is disabled. */
1970 if (!ssh_X11_fwd_enabled
) {
1971 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1972 PKT_INT
, GET_32BIT(pktin
.body
),
1974 logevent("Rejected X11 connect request");
1976 c
= smalloc(sizeof(struct ssh_channel
));
1978 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
1979 logevent("opening X11 forward connection failed");
1981 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
1982 PKT_INT
, GET_32BIT(pktin
.body
),
1985 logevent("opening X11 forward connection succeeded");
1986 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
1988 break; /* found a free number */
1991 c
->remoteid
= GET_32BIT(pktin
.body
);
1994 c
->type
= CHAN_X11
; /* identify channel type */
1995 add234(ssh_channels
, c
);
1996 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1997 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1999 logevent("Opened X11 forward channel");
2002 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
2003 /* Remote side is trying to open a channel to talk to our
2004 * agent. Give them back a local channel number. */
2006 struct ssh_channel
*c
;
2009 /* Refuse if agent forwarding is disabled. */
2010 if (!ssh_agentfwd_enabled
) {
2011 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2012 PKT_INT
, GET_32BIT(pktin
.body
),
2016 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
2018 break; /* found a free number */
2021 c
= smalloc(sizeof(struct ssh_channel
));
2022 c
->remoteid
= GET_32BIT(pktin
.body
);
2025 c
->type
= CHAN_AGENT
; /* identify channel type */
2026 c
->u
.a
.lensofar
= 0;
2027 add234(ssh_channels
, c
);
2028 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2029 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2032 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2033 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2034 /* Remote side closes a channel. */
2035 unsigned i
= GET_32BIT(pktin
.body
);
2036 struct ssh_channel
*c
;
2037 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2040 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2041 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2042 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2043 logevent("X11 connection closed");
2044 assert(c
->u
.x11
.s
!= NULL
);
2045 x11_close(c
->u
.x11
.s
);
2048 c
->closes
|= closetype
;
2049 if (c
->closes
== 3) {
2050 del234(ssh_channels
, c
);
2054 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2055 /* Data sent down one of our channels. */
2056 int i
= GET_32BIT(pktin
.body
);
2057 int len
= GET_32BIT(pktin
.body
+4);
2058 unsigned char *p
= pktin
.body
+8;
2059 struct ssh_channel
*c
;
2060 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2064 x11_send(c
->u
.x11
.s
, p
, len
);
2067 /* Data for an agent message. Buffer it. */
2069 if (c
->u
.a
.lensofar
< 4) {
2070 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2071 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2072 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2074 if (c
->u
.a
.lensofar
== 4) {
2075 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2076 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2077 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2079 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2080 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2081 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2082 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2084 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2085 void *reply
, *sentreply
;
2087 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2092 /* Fake SSH_AGENT_FAILURE. */
2093 sentreply
= "\0\0\0\1\5";
2096 send_packet(SSH1_MSG_CHANNEL_DATA
,
2097 PKT_INT
, c
->remoteid
,
2099 PKT_DATA
, sentreply
, replylen
,
2103 sfree(c
->u
.a
.message
);
2104 c
->u
.a
.lensofar
= 0;
2110 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2111 /* may be from EXEC_SHELL on some servers */
2112 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2113 /* may be from EXEC_SHELL on some servers
2114 * if no pty is available or in other odd cases. Ignore */
2115 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2116 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2118 bombout(("Strange packet received: type %d", pktin
.type
));
2123 int len
= min(inlen
, 512);
2124 send_packet(SSH1_CMSG_STDIN_DATA
,
2125 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2136 * Utility routine for decoding comma-separated strings in KEXINIT.
2138 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2139 int needlen
= strlen(needle
);
2142 * Is it at the start of the string?
2144 if (haylen
>= needlen
&& /* haystack is long enough */
2145 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2146 (haylen
== needlen
|| haystack
[needlen
] == ',')
2147 /* either , or EOS follows */
2151 * If not, search for the next comma and resume after that.
2152 * If no comma found, terminate.
2154 while (haylen
> 0 && *haystack
!= ',')
2155 haylen
--, haystack
++;
2158 haylen
--, haystack
++; /* skip over comma itself */
2163 * SSH2 key creation method.
2165 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2167 /* First 20 bytes. */
2170 SHA_Bytes(&s
, H
, 20);
2171 SHA_Bytes(&s
, &chr
, 1);
2172 SHA_Bytes(&s
, sessid
, 20);
2173 SHA_Final(&s
, keyspace
);
2174 /* Next 20 bytes. */
2177 SHA_Bytes(&s
, H
, 20);
2178 SHA_Bytes(&s
, keyspace
, 20);
2179 SHA_Final(&s
, keyspace
+20);
2183 * Handle the SSH2 transport layer.
2185 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2187 static int i
, j
, len
, nbits
;
2189 static Bignum p
, g
, e
, f
, K
;
2190 static int kex_init_value
, kex_reply_value
;
2191 static const struct ssh_mac
**maclist
;
2193 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
2194 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
2195 static const struct ssh_mac
*csmac_tobe
= NULL
;
2196 static const struct ssh_mac
*scmac_tobe
= NULL
;
2197 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2198 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2199 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2200 static int hostkeylen
, siglen
;
2201 static void *hkey
; /* actual host key */
2202 static unsigned char exchange_hash
[20];
2203 static unsigned char first_exchange_hash
[20];
2204 static unsigned char keyspace
[40];
2205 static const struct ssh2_ciphers
*preferred_cipher
;
2206 static const struct ssh_compress
*preferred_comp
;
2207 static int first_kex
;
2214 * Set up the preferred cipher and compression.
2216 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2217 preferred_cipher
= &ssh2_blowfish
;
2218 } else if (cfg
.cipher
== CIPHER_DES
) {
2219 logevent("Single DES not supported in SSH2; using 3DES");
2220 preferred_cipher
= &ssh2_3des
;
2221 } else if (cfg
.cipher
== CIPHER_3DES
) {
2222 preferred_cipher
= &ssh2_3des
;
2223 } else if (cfg
.cipher
== CIPHER_AES
) {
2224 preferred_cipher
= &ssh2_aes
;
2226 /* Shouldn't happen, but we do want to initialise to _something_. */
2227 preferred_cipher
= &ssh2_3des
;
2229 if (cfg
.compression
)
2230 preferred_comp
= &ssh_zlib
;
2232 preferred_comp
= &ssh_comp_none
;
2235 * Be prepared to work around the buggy MAC problem.
2238 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2240 maclist
= macs
, nmacs
= lenof(macs
);
2244 * Construct and send our key exchange packet.
2246 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2247 for (i
= 0; i
< 16; i
++)
2248 ssh2_pkt_addbyte((unsigned char)random_byte());
2249 /* List key exchange algorithms. */
2250 ssh2_pkt_addstring_start();
2251 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2252 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2253 if (i
< lenof(kex_algs
)-1)
2254 ssh2_pkt_addstring_str(",");
2256 /* List server host key algorithms. */
2257 ssh2_pkt_addstring_start();
2258 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2259 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2260 if (i
< lenof(hostkey_algs
)-1)
2261 ssh2_pkt_addstring_str(",");
2263 /* List client->server encryption algorithms. */
2264 ssh2_pkt_addstring_start();
2265 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2266 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2267 for (j
= 0; j
< c
->nciphers
; j
++) {
2268 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2269 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2270 ssh2_pkt_addstring_str(",");
2273 /* List server->client encryption algorithms. */
2274 ssh2_pkt_addstring_start();
2275 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2276 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2277 for (j
= 0; j
< c
->nciphers
; j
++) {
2278 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2279 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2280 ssh2_pkt_addstring_str(",");
2283 /* List client->server MAC algorithms. */
2284 ssh2_pkt_addstring_start();
2285 for (i
= 0; i
< nmacs
; i
++) {
2286 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2288 ssh2_pkt_addstring_str(",");
2290 /* List server->client MAC algorithms. */
2291 ssh2_pkt_addstring_start();
2292 for (i
= 0; i
< nmacs
; i
++) {
2293 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2295 ssh2_pkt_addstring_str(",");
2297 /* List client->server compression algorithms. */
2298 ssh2_pkt_addstring_start();
2299 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2300 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2301 ssh2_pkt_addstring_str(c
->name
);
2302 if (i
< lenof(compressions
))
2303 ssh2_pkt_addstring_str(",");
2305 /* List server->client compression algorithms. */
2306 ssh2_pkt_addstring_start();
2307 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2308 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2309 ssh2_pkt_addstring_str(c
->name
);
2310 if (i
< lenof(compressions
))
2311 ssh2_pkt_addstring_str(",");
2313 /* List client->server languages. Empty list. */
2314 ssh2_pkt_addstring_start();
2315 /* List server->client languages. Empty list. */
2316 ssh2_pkt_addstring_start();
2317 /* First KEX packet does _not_ follow, because we're not that brave. */
2318 ssh2_pkt_addbool(FALSE
);
2320 ssh2_pkt_adduint32(0);
2322 exhash
= exhashbase
;
2323 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2327 if (!ispkt
) crWaitUntil(ispkt
);
2328 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2331 * Now examine the other side's KEXINIT to see what we're up
2334 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2335 bombout(("expected key exchange packet from server"));
2338 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2339 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2340 pktin
.savedpos
+= 16; /* skip garbage cookie */
2341 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2342 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2343 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2348 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2349 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2350 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2351 hostkey
= hostkey_algs
[i
];
2355 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2356 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2357 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2358 for (j
= 0; j
< c
->nciphers
; j
++) {
2359 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2360 cscipher_tobe
= c
->list
[j
];
2367 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2368 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2369 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2370 for (j
= 0; j
< c
->nciphers
; j
++) {
2371 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2372 sccipher_tobe
= c
->list
[j
];
2379 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2380 for (i
= 0; i
< nmacs
; i
++) {
2381 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2382 csmac_tobe
= maclist
[i
];
2386 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2387 for (i
= 0; i
< nmacs
; i
++) {
2388 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2389 scmac_tobe
= maclist
[i
];
2393 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2394 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2395 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2396 if (in_commasep_string(c
->name
, str
, len
)) {
2401 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2402 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2403 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2404 if (in_commasep_string(c
->name
, str
, len
)) {
2411 * If we're doing Diffie-Hellman group exchange, start by
2412 * requesting a group.
2414 if (kex
== &ssh_diffiehellman_gex
) {
2417 logevent("Doing Diffie-Hellman group exchange");
2419 * Work out number of bits. We start with the maximum key
2420 * length of either cipher...
2422 csbits
= cscipher_tobe
->keylen
;
2423 scbits
= sccipher_tobe
->keylen
;
2424 nbits
= (csbits
> scbits ? csbits
: scbits
);
2425 /* The keys only have 160-bit entropy, since they're based on
2426 * a SHA-1 hash. So cap the key size at 160 bits. */
2427 if (nbits
> 160) nbits
= 160;
2429 * ... and then work out how big a DH group we will need to
2430 * allow that much data.
2432 nbits
= 512 << ((nbits
-1) / 64);
2433 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
2434 ssh2_pkt_adduint32(nbits
);
2438 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
2439 bombout(("expected key exchange group packet from server"));
2442 p
= ssh2_pkt_getmp();
2443 g
= ssh2_pkt_getmp();
2444 dh_setup_group(p
, g
);
2445 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
2446 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
2449 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
2450 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
2453 logevent("Doing Diffie-Hellman key exchange");
2455 * Now generate and send e for Diffie-Hellman.
2458 ssh2_pkt_init(kex_init_value
);
2463 if (pktin
.type
!= kex_reply_value
) {
2464 bombout(("expected key exchange reply packet from server"));
2467 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2468 f
= ssh2_pkt_getmp();
2469 ssh2_pkt_getstring(&sigdata
, &siglen
);
2473 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2474 if (kex
== &ssh_diffiehellman_gex
) {
2475 sha_uint32(&exhash
, nbits
);
2476 sha_mpint(&exhash
, p
);
2477 sha_mpint(&exhash
, g
);
2479 sha_mpint(&exhash
, e
);
2480 sha_mpint(&exhash
, f
);
2481 sha_mpint(&exhash
, K
);
2482 SHA_Final(&exhash
, exchange_hash
);
2487 debug(("Exchange hash is:\r\n"));
2488 for (i
= 0; i
< 20; i
++)
2489 debug((" %02x", exchange_hash
[i
]));
2493 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2494 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2495 bombout(("Server failed host key check"));
2500 * Expect SSH2_MSG_NEWKEYS from server.
2503 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2504 bombout(("expected new-keys packet from server"));
2509 * Authenticate remote host: verify host key. (We've already
2510 * checked the signature of the exchange hash.)
2512 keystr
= hostkey
->fmtkey(hkey
);
2513 fingerprint
= hostkey
->fingerprint(hkey
);
2514 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2515 keystr
, fingerprint
);
2516 if (first_kex
) { /* don't bother logging this in rekeys */
2517 logevent("Host key fingerprint is:");
2518 logevent(fingerprint
);
2522 hostkey
->freekey(hkey
);
2525 * Send SSH2_MSG_NEWKEYS.
2527 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2531 * Create and initialise session keys.
2533 cscipher
= cscipher_tobe
;
2534 sccipher
= sccipher_tobe
;
2537 cscomp
= cscomp_tobe
;
2538 sccomp
= sccomp_tobe
;
2539 cscomp
->compress_init();
2540 sccomp
->decompress_init();
2542 * Set IVs after keys. Here we use the exchange hash from the
2543 * _first_ key exchange.
2546 memcpy(first_exchange_hash
, exchange_hash
, sizeof(exchange_hash
));
2547 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'C', keyspace
);
2548 cscipher
->setcskey(keyspace
);
2549 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'D', keyspace
);
2550 sccipher
->setsckey(keyspace
);
2551 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'A', keyspace
);
2552 cscipher
->setcsiv(keyspace
);
2553 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'B', keyspace
);
2554 sccipher
->setsciv(keyspace
);
2555 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'E', keyspace
);
2556 csmac
->setcskey(keyspace
);
2557 ssh2_mkkey(K
, exchange_hash
, first_exchange_hash
, 'F', keyspace
);
2558 scmac
->setsckey(keyspace
);
2561 * If this is the first key exchange phase, we must pass the
2562 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2563 * wants to see it but because it will need time to initialise
2564 * itself before it sees an actual packet. In subsequent key
2565 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2566 * it would only confuse the layer above.
2574 * Now we're encrypting. Begin returning 1 to the protocol main
2575 * function so that other things can run on top of the
2576 * transport. If we ever see a KEXINIT, we must go back to the
2579 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2582 logevent("Server initiated key re-exchange");
2583 goto begin_key_exchange
;
2589 * Add data to an SSH2 channel output buffer.
2591 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2592 if (c
->v2
.outbufsize
<
2593 c
->v2
.outbuflen
+ len
) {
2595 c
->v2
.outbuflen
+ len
+ 1024;
2596 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2599 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2601 c
->v2
.outbuflen
+= len
;
2605 * Attempt to send data on an SSH2 channel.
2607 static void ssh2_try_send(struct ssh_channel
*c
) {
2608 while (c
->v2
.remwindow
> 0 &&
2609 c
->v2
.outbuflen
> 0) {
2610 unsigned len
= c
->v2
.remwindow
;
2611 if (len
> c
->v2
.outbuflen
)
2612 len
= c
->v2
.outbuflen
;
2613 if (len
> c
->v2
.remmaxpkt
)
2614 len
= c
->v2
.remmaxpkt
;
2615 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2616 ssh2_pkt_adduint32(c
->remoteid
);
2617 ssh2_pkt_addstring_start();
2618 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2620 c
->v2
.outbuflen
-= len
;
2621 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2623 c
->v2
.remwindow
-= len
;
2628 * Handle the SSH2 userauth and connection layers.
2630 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2632 static unsigned long remote_winsize
;
2633 static unsigned long remote_maxpkt
;
2638 * Request userauth protocol, and await a response to it.
2640 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2641 ssh2_pkt_addstring("ssh-userauth");
2643 crWaitUntilV(ispkt
);
2644 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2645 bombout(("Server refused user authentication protocol"));
2650 * FIXME: currently we support only password authentication.
2651 * (This places us technically in violation of the SSH2 spec.
2652 * We must fix this.)
2656 * Get a username and a password.
2658 static char username
[100];
2659 static char password
[100];
2663 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2664 c_write("login as: ", 10);
2667 crWaitUntilV(!ispkt
);
2668 while (inlen
--) switch (c
= *in
++) {
2675 c_write("\b \b", 3);
2681 c_write("\b \b", 3);
2690 if (((c
>= ' ' && c
<= '~') ||
2691 ((unsigned char)c
>= 160)) && pos
< 40) {
2692 username
[pos
++] = c
;
2699 username
[strcspn(username
, "\n\r")] = '\0';
2702 strncpy(username
, cfg
.username
, 99);
2703 username
[99] = '\0';
2704 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2705 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2706 c_write(stuff
, strlen(stuff
));
2710 if (ssh_get_password
) {
2712 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2713 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2715 * get_password failed to get a password (for
2716 * example because one was supplied on the command
2717 * line which has already failed to work).
2720 logevent("No more passwords to try");
2721 ssh_state
= SSH_STATE_CLOSED
;
2725 c_write("password: ", 10);
2730 crWaitUntilV(!ispkt
);
2731 while (inlen
--) switch (c
= *in
++) {
2748 if (((c
>= ' ' && c
<= '~') ||
2749 ((unsigned char)c
>= 160)) && pos
< 40)
2750 password
[pos
++] = c
;
2758 * We send the password packet lumped tightly together with
2759 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
2760 * string long enough to make the total length of the two
2761 * packets constant. This should ensure that a passive
2762 * listener doing traffic analyis can't work out the length
2765 * For this to work, we need an assumption about the
2766 * maximum length of the password packet. I think 256 is
2767 * pretty conservative. Anyone using a password longer than
2768 * that probably doesn't have much to worry about from
2769 * people who find out how long their password is!
2771 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2772 ssh2_pkt_addstring(username
);
2773 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2774 ssh2_pkt_addstring("password");
2775 ssh2_pkt_addbool(FALSE
);
2776 ssh2_pkt_addstring(password
);
2779 * We'll include a string that's an exact multiple of the
2780 * cipher block size. If the cipher is NULL for some
2781 * reason, we don't do this trick at all because we gain
2786 ssh2_pkt_init(SSH2_MSG_IGNORE
);
2787 ssh2_pkt_addstring_start();
2788 for (i
= deferred_len
; i
<= 256; i
+= cscipher
->blksize
) {
2789 for (j
= 0; j
< cscipher
->blksize
; j
++) {
2790 char c
= (char)random_byte();
2791 ssh2_pkt_addstring_data(&c
, 1);
2796 ssh2_pkt_defersend();
2798 crWaitUntilV(ispkt
);
2799 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2800 c_write("Access denied\r\n", 15);
2801 logevent("Authentication refused");
2807 * Now we're authenticated for the connection protocol. The
2808 * connection protocol will automatically have started at this
2809 * point; there's no need to send SERVICE_REQUEST.
2813 * So now create a channel with a session in it.
2815 mainchan
= smalloc(sizeof(struct ssh_channel
));
2816 mainchan
->localid
= 100; /* as good as any */
2817 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2818 ssh2_pkt_addstring("session");
2819 ssh2_pkt_adduint32(mainchan
->localid
);
2820 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2821 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2823 crWaitUntilV(ispkt
);
2824 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2825 bombout(("Server refused to open a session"));
2827 /* FIXME: error data comes back in FAILURE packet */
2829 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2830 bombout(("Server's channel confirmation cited wrong channel"));
2833 mainchan
->remoteid
= ssh2_pkt_getuint32();
2834 mainchan
->type
= CHAN_MAINSESSION
;
2835 mainchan
->closes
= 0;
2836 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
2837 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
2838 mainchan
->v2
.outbuffer
= NULL
;
2839 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
2840 ssh_channels
= newtree234(ssh_channelcmp
);
2841 add234(ssh_channels
, mainchan
);
2842 logevent("Opened channel for session");
2845 * Potentially enable X11 forwarding.
2847 if (cfg
.x11_forward
) {
2848 char proto
[20], data
[64];
2849 logevent("Requesting X11 forwarding");
2850 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2851 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2852 ssh2_pkt_adduint32(mainchan
->remoteid
);
2853 ssh2_pkt_addstring("x11-req");
2854 ssh2_pkt_addbool(1); /* want reply */
2855 ssh2_pkt_addbool(0); /* many connections */
2856 ssh2_pkt_addstring(proto
);
2857 ssh2_pkt_addstring(data
);
2858 ssh2_pkt_adduint32(0); /* screen number */
2862 crWaitUntilV(ispkt
);
2863 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2864 unsigned i
= ssh2_pkt_getuint32();
2865 struct ssh_channel
*c
;
2866 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2868 continue; /* nonexistent channel */
2869 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2871 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2873 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2874 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2875 bombout(("Server got confused by X11 forwarding request"));
2878 logevent("X11 forwarding refused");
2880 logevent("X11 forwarding enabled");
2881 ssh_X11_fwd_enabled
= TRUE
;
2886 * Now allocate a pty for the session.
2889 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2890 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2891 ssh2_pkt_addstring("pty-req");
2892 ssh2_pkt_addbool(1); /* want reply */
2893 ssh2_pkt_addstring(cfg
.termtype
);
2894 ssh2_pkt_adduint32(cols
);
2895 ssh2_pkt_adduint32(rows
);
2896 ssh2_pkt_adduint32(0); /* pixel width */
2897 ssh2_pkt_adduint32(0); /* pixel height */
2898 ssh2_pkt_addstring_start();
2899 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2901 ssh_state
= SSH_STATE_INTERMED
;
2904 crWaitUntilV(ispkt
);
2905 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2906 unsigned i
= ssh2_pkt_getuint32();
2907 struct ssh_channel
*c
;
2908 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2910 continue; /* nonexistent channel */
2911 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2913 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2915 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2916 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2917 bombout(("Server got confused by pty request"));
2920 c_write("Server refused to allocate pty\r\n", 32);
2921 ssh_editing
= ssh_echoing
= 1;
2923 logevent("Allocated pty");
2926 ssh_editing
= ssh_echoing
= 1;
2930 * Start a shell or a remote command.
2932 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2933 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2934 if (cfg
.ssh_subsys
) {
2935 ssh2_pkt_addstring("subsystem");
2936 ssh2_pkt_addbool(1); /* want reply */
2937 ssh2_pkt_addstring(cfg
.remote_cmd
);
2938 } else if (*cfg
.remote_cmd
) {
2939 ssh2_pkt_addstring("exec");
2940 ssh2_pkt_addbool(1); /* want reply */
2941 ssh2_pkt_addstring(cfg
.remote_cmd
);
2943 ssh2_pkt_addstring("shell");
2944 ssh2_pkt_addbool(1); /* want reply */
2948 crWaitUntilV(ispkt
);
2949 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2950 unsigned i
= ssh2_pkt_getuint32();
2951 struct ssh_channel
*c
;
2952 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2954 continue; /* nonexistent channel */
2955 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
2957 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2958 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2959 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2960 bombout(("Server got confused by shell/command request"));
2963 bombout(("Server refused to start a shell/command"));
2966 logevent("Started a shell/command");
2969 ssh_state
= SSH_STATE_SESSION
;
2973 ssh_special(TS_EOF
);
2978 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2981 static int try_send
;
2985 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2986 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2989 unsigned i
= ssh2_pkt_getuint32();
2990 struct ssh_channel
*c
;
2991 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2993 continue; /* nonexistent channel */
2994 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2995 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2996 continue; /* extended but not stderr */
2997 ssh2_pkt_getstring(&data
, &length
);
3000 case CHAN_MAINSESSION
:
3001 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
3005 x11_send(c
->u
.x11
.s
, data
, length
);
3009 * Enlarge the window again at the remote
3010 * side, just in case it ever runs down and
3011 * they fail to send us any more data.
3013 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3014 ssh2_pkt_adduint32(c
->remoteid
);
3015 ssh2_pkt_adduint32(length
);
3018 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
3019 ssh_state
= SSH_STATE_CLOSED
;
3020 logevent("Received disconnect message");
3022 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
3023 continue; /* exit status et al; ignore (FIXME?) */
3024 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
3025 unsigned i
= ssh2_pkt_getuint32();
3026 struct ssh_channel
*c
;
3028 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3030 continue; /* nonexistent channel */
3032 if (c
->type
== CHAN_X11
) {
3034 * Remote EOF on an X11 channel means we should
3035 * wrap up and close the channel ourselves.
3037 x11_close(c
->u
.x11
.s
);
3040 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
3041 unsigned i
= ssh2_pkt_getuint32();
3042 struct ssh_channel
*c
;
3045 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3047 continue; /* nonexistent channel */
3048 if (c
->closes
== 0) {
3049 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3050 ssh2_pkt_adduint32(c
->remoteid
);
3053 /* Do pre-close processing on the channel. */
3055 case CHAN_MAINSESSION
:
3056 break; /* nothing to see here, move along */
3060 del234(ssh_channels
, c
);
3061 sfree(c
->v2
.outbuffer
);
3065 * See if that was the last channel left open.
3067 c
= first234(ssh_channels
, &e
);
3069 logevent("All channels closed. Disconnecting");
3070 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3071 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3072 ssh2_pkt_addstring("All open channels closed");
3073 ssh2_pkt_addstring("en"); /* language tag */
3075 ssh_state
= SSH_STATE_CLOSED
;
3078 continue; /* remote sends close; ignore (FIXME) */
3079 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3080 unsigned i
= ssh2_pkt_getuint32();
3081 struct ssh_channel
*c
;
3082 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3084 continue; /* nonexistent channel */
3085 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3087 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3091 struct ssh_channel
*c
;
3092 ssh2_pkt_getstring(&type
, &typelen
);
3093 c
= smalloc(sizeof(struct ssh_channel
));
3095 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3096 if (!ssh_X11_fwd_enabled
)
3097 error
= "X11 forwarding is not enabled";
3098 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3099 error
= "Unable to open an X11 connection";
3104 error
= "Unsupported channel type requested";
3107 c
->remoteid
= ssh2_pkt_getuint32();
3109 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3110 ssh2_pkt_adduint32(c
->remoteid
);
3111 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3112 ssh2_pkt_addstring(error
);
3113 ssh2_pkt_addstring("en"); /* language tag */
3117 struct ssh_channel
*d
;
3121 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3124 break; /* found a free number */
3129 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3130 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3131 c
->v2
.outbuffer
= NULL
;
3132 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3133 add234(ssh_channels
, c
);
3134 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3135 ssh2_pkt_adduint32(c
->remoteid
);
3136 ssh2_pkt_adduint32(c
->localid
);
3137 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3138 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3142 bombout(("Strange packet received: type %d", pktin
.type
));
3147 * We have spare data. Add it to the channel buffer.
3149 ssh2_add_channel_data(mainchan
, in
, inlen
);
3154 struct ssh_channel
*c
;
3156 * Try to send data on all channels if we can.
3158 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3167 * Handle the top-level SSH2 protocol.
3169 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3171 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3173 do_ssh2_authconn(in
, inlen
, ispkt
);
3177 * Called to set up the connection.
3179 * Returns an error message, or NULL on success.
3181 static char *ssh_init (char *host
, int port
, char **realhost
) {
3185 if(crypto_startup() == 0)
3186 return "Microsoft high encryption pack not installed!";
3193 p
= connect_to_host(host
, port
, realhost
);
3201 * Called to send data down the Telnet connection.
3203 static void ssh_send (char *buf
, int len
) {
3204 if (s
== NULL
|| ssh_protocol
== NULL
)
3207 ssh_protocol(buf
, len
, 0);
3211 * Called to set the size of the window from SSH's POV.
3213 static void ssh_size(void) {
3214 switch (ssh_state
) {
3215 case SSH_STATE_BEFORE_SIZE
:
3216 case SSH_STATE_PREPACKET
:
3217 case SSH_STATE_CLOSED
:
3218 break; /* do nothing */
3219 case SSH_STATE_INTERMED
:
3220 size_needed
= TRUE
; /* buffer for later */
3222 case SSH_STATE_SESSION
:
3224 if (ssh_version
== 1) {
3225 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3226 PKT_INT
, rows
, PKT_INT
, cols
,
3227 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3229 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3230 ssh2_pkt_adduint32(mainchan
->remoteid
);
3231 ssh2_pkt_addstring("window-change");
3232 ssh2_pkt_addbool(0);
3233 ssh2_pkt_adduint32(cols
);
3234 ssh2_pkt_adduint32(rows
);
3235 ssh2_pkt_adduint32(0);
3236 ssh2_pkt_adduint32(0);
3245 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3246 * can send an EOF and collect resulting output (e.g. `plink
3249 static void ssh_special (Telnet_Special code
) {
3250 if (code
== TS_EOF
) {
3251 if (ssh_state
!= SSH_STATE_SESSION
) {
3253 * Buffer the EOF in case we are pre-SESSION, so we can
3254 * send it as soon as we reach SESSION.
3260 if (ssh_version
== 1) {
3261 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3263 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3264 ssh2_pkt_adduint32(mainchan
->remoteid
);
3267 logevent("Sent EOF message");
3268 } else if (code
== TS_PING
) {
3269 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3271 if (ssh_version
== 1) {
3272 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3274 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3275 ssh2_pkt_addstring_start();
3283 static Socket
ssh_socket(void) { return s
; }
3285 static int ssh_sendok(void) { return ssh_send_ok
; }
3287 static int ssh_ldisc(int option
) {
3288 if (option
== LD_ECHO
) return ssh_echoing
;
3289 if (option
== LD_EDIT
) return ssh_editing
;
3293 Backend ssh_backend
= {