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 SSH2_MSG_DISCONNECT 1 /* 0x1 */
72 #define SSH2_MSG_IGNORE 2 /* 0x2 */
73 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
74 #define SSH2_MSG_DEBUG 4 /* 0x4 */
75 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
76 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
77 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
78 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
79 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
80 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
81 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
82 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
83 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
84 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
85 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
86 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
87 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
88 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
89 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
90 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
91 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
92 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
93 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
94 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
95 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
96 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
97 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
98 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
99 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
100 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
101 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
102 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
103 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
104 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
106 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
107 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
108 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
109 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
110 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
111 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
112 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
113 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
114 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
115 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
116 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
118 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
119 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
120 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
121 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
123 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
125 #define GET_32BIT(cp) \
126 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
127 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
128 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
129 ((unsigned long)(unsigned char)(cp)[3]))
131 #define PUT_32BIT(cp, value) { \
132 (cp)[0] = (unsigned char)((value) >> 24); \
133 (cp)[1] = (unsigned char)((value) >> 16); \
134 (cp)[2] = (unsigned char)((value) >> 8); \
135 (cp)[3] = (unsigned char)(value); }
137 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
139 /* Coroutine mechanics for the sillier bits of the code */
140 #define crBegin1 static int crLine = 0;
141 #define crBegin2 switch(crLine) { case 0:;
142 #define crBegin crBegin1; crBegin2;
143 #define crFinish(z) } crLine = 0; return (z)
144 #define crFinishV } crLine = 0; return
145 #define crReturn(z) \
147 crLine=__LINE__; return (z); case __LINE__:;\
151 crLine=__LINE__; return; case __LINE__:;\
153 #define crStop(z) do{ crLine = 0; return (z); }while(0)
154 #define crStopV do{ crLine = 0; return; }while(0)
155 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
156 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
158 extern char *x11_init (Socket
*, char *, void *);
159 extern void x11_close (Socket
);
160 extern void x11_send (Socket
, char *, int);
161 extern void x11_invent_auth(char *, int, char *, int);
164 * Ciphers for SSH2. We miss out single-DES because it isn't
165 * supported; also 3DES and Blowfish are both done differently from
166 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
167 * endianness and different-sized keys.)
169 const static struct ssh2_ciphers
*ciphers
[] = {
175 const static struct ssh_kex
*kex_algs
[] = {
176 #ifdef DO_DIFFIE_HELLMAN_GEX
177 &ssh_diffiehellman_gex
,
179 &ssh_diffiehellman
};
181 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
183 static void nullmac_key(unsigned char *key
) { }
184 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
185 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
186 const static struct ssh_mac ssh_mac_none
= {
187 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
189 const static struct ssh_mac
*macs
[] = {
190 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
191 const static struct ssh_mac
*buggymacs
[] = {
192 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
194 static void ssh_comp_none_init(void) { }
195 static int ssh_comp_none_block(unsigned char *block
, int len
,
196 unsigned char **outblock
, int *outlen
) {
199 const static struct ssh_compress ssh_comp_none
= {
201 ssh_comp_none_init
, ssh_comp_none_block
,
202 ssh_comp_none_init
, ssh_comp_none_block
204 extern const struct ssh_compress ssh_zlib
;
205 const static struct ssh_compress
*compressions
[] = {
206 &ssh_zlib
, &ssh_comp_none
};
208 enum { /* channel types */
215 * 2-3-4 tree storing channels.
218 unsigned remoteid
, localid
;
221 struct ssh2_data_channel
{
222 unsigned char *outbuffer
;
223 unsigned outbuflen
, outbufsize
;
224 unsigned remwindow
, remmaxpkt
;
227 struct ssh_agent_channel
{
228 unsigned char *message
;
229 unsigned char msglen
[4];
230 int lensofar
, totallen
;
232 struct ssh_x11_channel
{
247 static SHA_State exhash
, exhashbase
;
249 static Socket s
= NULL
;
251 static unsigned char session_key
[32];
252 static int ssh1_compressing
;
253 static int ssh_agentfwd_enabled
;
254 static int ssh_X11_fwd_enabled
;
255 static const struct ssh_cipher
*cipher
= NULL
;
256 static const struct ssh2_cipher
*cscipher
= NULL
;
257 static const struct ssh2_cipher
*sccipher
= NULL
;
258 static const struct ssh_mac
*csmac
= NULL
;
259 static const struct ssh_mac
*scmac
= NULL
;
260 static const struct ssh_compress
*cscomp
= NULL
;
261 static const struct ssh_compress
*sccomp
= NULL
;
262 static const struct ssh_kex
*kex
= NULL
;
263 static const struct ssh_signkey
*hostkey
= NULL
;
264 static unsigned char ssh2_session_id
[20];
265 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
267 static char *savedhost
;
268 static int savedport
;
269 static int ssh_send_ok
;
270 static int ssh_echoing
, ssh_editing
;
272 static tree234
*ssh_channels
; /* indexed by local id */
273 static struct ssh_channel
*mainchan
; /* primary session channel */
277 SSH_STATE_BEFORE_SIZE
,
281 } ssh_state
= SSH_STATE_PREPACKET
;
283 static int size_needed
= FALSE
, eof_needed
= FALSE
;
285 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
286 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
287 static unsigned char *deferred_send_data
= NULL
;
288 static int deferred_len
= 0, deferred_size
= 0;
290 static int ssh_version
;
291 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
292 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
293 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
294 static void ssh_size(void);
295 static void ssh_special (Telnet_Special
);
296 static void ssh2_try_send(struct ssh_channel
*c
);
297 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
299 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
301 static struct rdpkt1_state_tag
{
302 long len
, pad
, biglen
, to_read
;
303 unsigned long realcrc
, gotcrc
;
309 static struct rdpkt2_state_tag
{
310 long len
, pad
, payload
, packetlen
, maclen
;
313 unsigned long incoming_sequence
;
316 static int ssh_channelcmp(void *av
, void *bv
) {
317 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
318 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
319 if (a
->localid
< b
->localid
) return -1;
320 if (a
->localid
> b
->localid
) return +1;
323 static int ssh_channelfind(void *av
, void *bv
) {
324 unsigned *a
= (unsigned *)av
;
325 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
326 if (*a
< b
->localid
) return -1;
327 if (*a
> b
->localid
) return +1;
331 static void c_write (char *buf
, int len
) {
332 if ((flags
& FLAG_STDERR
)) {
334 for (i
= 0; i
< len
; i
++)
336 fputc(buf
[i
], stderr
);
339 from_backend(1, buf
, len
);
342 static void c_write_str (char *buf
) {
343 c_write(buf
, strlen(buf
));
347 * Collect incoming data in the incoming packet buffer.
348 * Decipher and verify the packet when it is completely read.
349 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
350 * Update the *data and *datalen variables.
351 * Return the additional nr of bytes needed, or 0 when
352 * a complete packet is available.
354 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
356 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
365 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
366 while ((*datalen
) == 0)
368 st
->len
= (st
->len
<< 8) + **data
;
369 (*data
)++, (*datalen
)--;
373 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
374 st
->len
= 0x300; /* big enough to carry to end */
378 st
->pad
= 8 - (st
->len
% 8);
379 st
->biglen
= st
->len
+ st
->pad
;
380 pktin
.length
= st
->len
- 5;
382 if (pktin
.maxlen
< st
->biglen
) {
383 pktin
.maxlen
= st
->biglen
;
384 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
385 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
387 fatalbox("Out of memory");
390 st
->to_read
= st
->biglen
;
392 while (st
->to_read
> 0) {
393 st
->chunk
= st
->to_read
;
394 while ((*datalen
) == 0)
395 crReturn(st
->to_read
);
396 if (st
->chunk
> (*datalen
))
397 st
->chunk
= (*datalen
);
398 memcpy(st
->p
, *data
, st
->chunk
);
400 *datalen
-= st
->chunk
;
402 st
->to_read
-= st
->chunk
;
406 cipher
->decrypt(pktin
.data
, st
->biglen
);
408 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
409 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
410 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
414 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
415 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
416 if (st
->gotcrc
!= st
->realcrc
) {
417 bombout(("Incorrect CRC received on packet"));
421 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
423 if (ssh1_compressing
) {
424 unsigned char *decompblk
;
428 debug(("Packet payload pre-decompression:\n"));
429 for (i
= -1; i
< pktin
.length
; i
++)
430 debug((" %02x", (unsigned char)pktin
.body
[i
]));
433 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
434 &decompblk
, &decomplen
);
436 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
437 pktin
.maxlen
= st
->pad
+ decomplen
;
438 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
439 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
441 fatalbox("Out of memory");
444 memcpy(pktin
.body
-1, decompblk
, decomplen
);
446 pktin
.length
= decomplen
-1;
448 debug(("Packet payload post-decompression:\n"));
449 for (i
= -1; i
< pktin
.length
; i
++)
450 debug((" %02x", (unsigned char)pktin
.body
[i
]));
455 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
456 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
457 pktin
.type
== SSH1_MSG_DEBUG
||
458 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
459 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
460 long strlen
= GET_32BIT(pktin
.body
);
461 if (strlen
+ 4 != pktin
.length
) {
462 bombout(("Received data packet with bogus string length"));
467 pktin
.type
= pktin
.body
[-1];
469 if (pktin
.type
== SSH1_MSG_DEBUG
) {
470 /* log debug message */
472 int strlen
= GET_32BIT(pktin
.body
);
473 strcpy(buf
, "Remote: ");
474 if (strlen
> 70) strlen
= 70;
475 memcpy(buf
+8, pktin
.body
+4, strlen
);
476 buf
[8+strlen
] = '\0';
479 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
487 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
489 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
497 st
->cipherblk
= sccipher
->blksize
;
500 if (st
->cipherblk
< 8)
503 if (pktin
.maxlen
< st
->cipherblk
) {
504 pktin
.maxlen
= st
->cipherblk
;
505 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
506 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
508 fatalbox("Out of memory");
512 * Acquire and decrypt the first block of the packet. This will
513 * contain the length and padding details.
515 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
516 while ((*datalen
) == 0)
517 crReturn(st
->cipherblk
-st
->i
);
518 pktin
.data
[st
->i
] = *(*data
)++;
522 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
527 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
530 * Now get the length and padding figures.
532 st
->len
= GET_32BIT(pktin
.data
);
533 st
->pad
= pktin
.data
[4];
536 * This enables us to deduce the payload length.
538 st
->payload
= st
->len
- st
->pad
- 1;
540 pktin
.length
= st
->payload
+ 5;
543 * So now we can work out the total packet length.
545 st
->packetlen
= st
->len
+ 4;
546 st
->maclen
= scmac ? scmac
->len
: 0;
549 * Adjust memory allocation if packet is too big.
551 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
552 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
553 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
554 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
556 fatalbox("Out of memory");
560 * Read and decrypt the remainder of the packet.
562 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
563 while ((*datalen
) == 0)
564 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
565 pktin
.data
[st
->i
] = *(*data
)++;
568 /* Decrypt everything _except_ the MAC. */
570 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
571 st
->packetlen
- st
->cipherblk
);
574 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
575 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
576 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
583 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
584 bombout(("Incorrect MAC received on packet"));
587 st
->incoming_sequence
++; /* whether or not we MACed */
590 * Decompress packet payload.
593 unsigned char *newpayload
;
595 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
596 &newpayload
, &newlen
)) {
597 if (pktin
.maxlen
< newlen
+5) {
598 pktin
.maxlen
= newlen
+5;
599 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
600 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
602 fatalbox("Out of memory");
604 pktin
.length
= 5 + newlen
;
605 memcpy(pktin
.data
+5, newpayload
, newlen
);
607 debug(("Post-decompression payload:\r\n"));
608 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
609 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
618 pktin
.type
= pktin
.data
[5];
620 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
621 goto next_packet
; /* FIXME: print DEBUG message */
626 static void ssh1_pktout_size(int len
) {
629 len
+= 5; /* type and CRC */
633 pktout
.length
= len
-5;
634 if (pktout
.maxlen
< biglen
) {
635 pktout
.maxlen
= biglen
;
637 /* Allocate enough buffer space for extra block
638 * for MS CryptEncrypt() */
639 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
640 srealloc(pktout
.data
, biglen
+12));
642 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
643 srealloc(pktout
.data
, biglen
+4));
646 fatalbox("Out of memory");
648 pktout
.body
= pktout
.data
+4+pad
+1;
651 static void s_wrpkt_start(int type
, int len
) {
652 ssh1_pktout_size(len
);
656 static int s_wrpkt_prepare(void) {
657 int pad
, len
, biglen
, i
;
660 pktout
.body
[-1] = pktout
.type
;
662 if (ssh1_compressing
) {
663 unsigned char *compblk
;
666 debug(("Packet payload pre-compression:\n"));
667 for (i
= -1; i
< pktout
.length
; i
++)
668 debug((" %02x", (unsigned char)pktout
.body
[i
]));
671 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
673 ssh1_pktout_size(complen
-1);
674 memcpy(pktout
.body
-1, compblk
, complen
);
677 debug(("Packet payload post-compression:\n"));
678 for (i
= -1; i
< pktout
.length
; i
++)
679 debug((" %02x", (unsigned char)pktout
.body
[i
]));
684 len
= pktout
.length
+ 5; /* type and CRC */
688 for (i
=0; i
<pad
; i
++)
689 pktout
.data
[i
+4] = random_byte();
690 crc
= crc32(pktout
.data
+4, biglen
-4);
691 PUT_32BIT(pktout
.data
+biglen
, crc
);
692 PUT_32BIT(pktout
.data
, len
);
695 debug(("Sending packet len=%d\r\n", biglen
+4));
696 for (i
= 0; i
< biglen
+4; i
++)
697 debug((" %02x", (unsigned char)pktout
.data
[i
]));
701 cipher
->encrypt(pktout
.data
+4, biglen
);
706 static void s_wrpkt(void) {
708 len
= s_wrpkt_prepare();
709 sk_write(s
, pktout
.data
, len
);
712 static void s_wrpkt_defer(void) {
714 len
= s_wrpkt_prepare();
715 if (deferred_len
+ len
> deferred_size
) {
716 deferred_size
= deferred_len
+ len
+ 128;
717 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
719 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
724 * Construct a packet with the specified contents.
726 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
728 unsigned char *p
, *argp
, argchar
;
729 unsigned long argint
;
730 int pktlen
, argtype
, arglen
;
734 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
737 (void) va_arg(ap1
, int);
741 (void) va_arg(ap1
, char);
745 (void) va_arg(ap1
, unsigned char *);
746 arglen
= va_arg(ap1
, int);
750 argp
= va_arg(ap1
, unsigned char *);
751 arglen
= strlen(argp
);
752 pktlen
+= 4 + arglen
;
755 bn
= va_arg(ap1
, Bignum
);
756 pktlen
+= ssh1_bignum_length(bn
);
763 s_wrpkt_start(pkttype
, pktlen
);
766 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
769 argint
= va_arg(ap2
, int);
770 PUT_32BIT(p
, argint
);
774 argchar
= va_arg(ap2
, unsigned char);
779 argp
= va_arg(ap2
, unsigned char *);
780 arglen
= va_arg(ap2
, int);
781 memcpy(p
, argp
, arglen
);
785 argp
= va_arg(ap2
, unsigned char *);
786 arglen
= strlen(argp
);
787 PUT_32BIT(p
, arglen
);
788 memcpy(p
+ 4, argp
, arglen
);
792 bn
= va_arg(ap2
, Bignum
);
793 p
+= ssh1_write_bignum(p
, bn
);
799 static void send_packet(int pkttype
, ...) {
801 va_start(ap1
, pkttype
);
802 va_start(ap2
, pkttype
);
803 construct_packet(pkttype
, ap1
, ap2
);
807 static void defer_packet(int pkttype
, ...) {
809 va_start(ap1
, pkttype
);
810 va_start(ap2
, pkttype
);
811 construct_packet(pkttype
, ap1
, ap2
);
815 static int ssh_versioncmp(char *a
, char *b
) {
817 unsigned long av
, bv
;
819 av
= strtoul(a
, &ae
, 10);
820 bv
= strtoul(b
, &be
, 10);
821 if (av
!= bv
) return (av
< bv ?
-1 : +1);
822 if (*ae
== '.') ae
++;
823 if (*be
== '.') be
++;
824 av
= strtoul(ae
, &ae
, 10);
825 bv
= strtoul(be
, &be
, 10);
826 if (av
!= bv
) return (av
< bv ?
-1 : +1);
832 * Utility routines for putting an SSH-protocol `string' and
833 * `uint32' into a SHA state.
836 static void sha_string(SHA_State
*s
, void *str
, int len
) {
837 unsigned char lenblk
[4];
838 PUT_32BIT(lenblk
, len
);
839 SHA_Bytes(s
, lenblk
, 4);
840 SHA_Bytes(s
, str
, len
);
843 static void sha_uint32(SHA_State
*s
, unsigned i
) {
844 unsigned char intblk
[4];
845 PUT_32BIT(intblk
, i
);
846 SHA_Bytes(s
, intblk
, 4);
850 * SSH2 packet construction functions.
852 static void ssh2_pkt_ensure(int length
) {
853 if (pktout
.maxlen
< length
) {
854 pktout
.maxlen
= length
+ 256;
855 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
856 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
858 fatalbox("Out of memory");
861 static void ssh2_pkt_adddata(void *data
, int len
) {
862 pktout
.length
+= len
;
863 ssh2_pkt_ensure(pktout
.length
);
864 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
866 static void ssh2_pkt_addbyte(unsigned char byte
) {
867 ssh2_pkt_adddata(&byte
, 1);
869 static void ssh2_pkt_init(int pkt_type
) {
871 ssh2_pkt_addbyte((unsigned char)pkt_type
);
873 static void ssh2_pkt_addbool(unsigned char value
) {
874 ssh2_pkt_adddata(&value
, 1);
876 static void ssh2_pkt_adduint32(unsigned long value
) {
879 ssh2_pkt_adddata(x
, 4);
881 static void ssh2_pkt_addstring_start(void) {
882 ssh2_pkt_adduint32(0);
883 pktout
.savedpos
= pktout
.length
;
885 static void ssh2_pkt_addstring_str(char *data
) {
886 ssh2_pkt_adddata(data
, strlen(data
));
887 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
888 pktout
.length
- pktout
.savedpos
);
890 static void ssh2_pkt_addstring_data(char *data
, int len
) {
891 ssh2_pkt_adddata(data
, len
);
892 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
893 pktout
.length
- pktout
.savedpos
);
895 static void ssh2_pkt_addstring(char *data
) {
896 ssh2_pkt_addstring_start();
897 ssh2_pkt_addstring_str(data
);
899 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
901 int i
, n
= (ssh1_bignum_bitcount(b
)+7)/8;
904 fatalbox("out of memory");
906 for (i
= 1; i
<= n
; i
++)
907 p
[i
] = bignum_byte(b
, n
-i
);
909 while (i
<= n
&& p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
911 memmove(p
, p
+i
, n
+1-i
);
915 static void ssh2_pkt_addmp(Bignum b
) {
918 p
= ssh2_mpint_fmt(b
, &len
);
919 ssh2_pkt_addstring_start();
920 ssh2_pkt_addstring_data(p
, len
);
925 * Construct an SSH2 final-form packet: compress it, encrypt it,
926 * put the MAC on it. Final packet, ready to be sent, is stored in
927 * pktout.data. Total length is returned.
929 static int ssh2_pkt_construct(void) {
930 int cipherblk
, maclen
, padding
, i
;
931 static unsigned long outgoing_sequence
= 0;
934 * Compress packet payload.
937 debug(("Pre-compression payload:\r\n"));
938 for (i
= 5; i
< pktout
.length
; i
++)
939 debug((" %02x", (unsigned char)pktout
.data
[i
]));
943 unsigned char *newpayload
;
945 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
946 &newpayload
, &newlen
)) {
948 ssh2_pkt_adddata(newpayload
, newlen
);
954 * Add padding. At least four bytes, and must also bring total
955 * length (minus MAC) up to a multiple of the block size.
957 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
958 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
960 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
961 maclen
= csmac ? csmac
->len
: 0;
962 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
963 pktout
.data
[4] = padding
;
964 for (i
= 0; i
< padding
; i
++)
965 pktout
.data
[pktout
.length
+ i
] = random_byte();
966 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
968 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
970 outgoing_sequence
++; /* whether or not we MACed */
973 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
974 for (i
= 0; i
< pktout
.length
+padding
; i
++)
975 debug((" %02x", (unsigned char)pktout
.data
[i
]));
980 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
982 /* Ready-to-send packet starts at pktout.data. We return length. */
983 return pktout
.length
+ padding
+ maclen
;
987 * Construct and send an SSH2 packet immediately.
989 static void ssh2_pkt_send(void) {
990 int len
= ssh2_pkt_construct();
991 sk_write(s
, pktout
.data
, len
);
995 * Construct an SSH2 packet and add it to a deferred data block.
996 * Useful for sending multiple packets in a single sk_write() call,
997 * to prevent a traffic-analysing listener from being able to work
998 * out the length of any particular packet (such as the password
1001 * Note that because SSH2 sequence-numbers its packets, this can
1002 * NOT be used as an m4-style `defer' allowing packets to be
1003 * constructed in one order and sent in another.
1005 static void ssh2_pkt_defer(void) {
1006 int len
= ssh2_pkt_construct();
1007 if (deferred_len
+ len
> deferred_size
) {
1008 deferred_size
= deferred_len
+ len
+ 128;
1009 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1011 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
1012 deferred_len
+= len
;
1016 * Send the whole deferred data block constructed by
1017 * ssh2_pkt_defer() or SSH1's defer_packet().
1019 static void ssh_pkt_defersend(void) {
1020 sk_write(s
, deferred_send_data
, deferred_len
);
1021 deferred_len
= deferred_size
= 0;
1022 sfree(deferred_send_data
);
1023 deferred_send_data
= NULL
;
1027 void bndebug(char *string
, Bignum b
) {
1030 p
= ssh2_mpint_fmt(b
, &len
);
1031 debug(("%s", string
));
1032 for (i
= 0; i
< len
; i
++)
1033 debug((" %02x", p
[i
]));
1039 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1042 p
= ssh2_mpint_fmt(b
, &len
);
1043 sha_string(s
, p
, len
);
1048 * SSH2 packet decode functions.
1050 static unsigned long ssh2_pkt_getuint32(void) {
1051 unsigned long value
;
1052 if (pktin
.length
- pktin
.savedpos
< 4)
1053 return 0; /* arrgh, no way to decline (FIXME?) */
1054 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1055 pktin
.savedpos
+= 4;
1058 static int ssh2_pkt_getbool(void) {
1059 unsigned long value
;
1060 if (pktin
.length
- pktin
.savedpos
< 1)
1061 return 0; /* arrgh, no way to decline (FIXME?) */
1062 value
= pktin
.data
[pktin
.savedpos
] != 0;
1066 static void ssh2_pkt_getstring(char **p
, int *length
) {
1068 if (pktin
.length
- pktin
.savedpos
< 4)
1070 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1071 pktin
.savedpos
+= 4;
1072 if (pktin
.length
- pktin
.savedpos
< *length
)
1074 *p
= pktin
.data
+pktin
.savedpos
;
1075 pktin
.savedpos
+= *length
;
1077 static Bignum
ssh2_pkt_getmp(void) {
1082 ssh2_pkt_getstring(&p
, &length
);
1086 bombout(("internal error: Can't handle negative mpints"));
1089 b
= bignum_from_bytes(p
, length
);
1093 static int do_ssh_init(unsigned char c
) {
1095 static char version
[10];
1096 static char vstring
[80];
1097 static char vlog
[sizeof(vstring
)+20];
1102 /* Search for the string "SSH-" in the input. */
1105 static const int transS
[] = { 1, 2, 2, 1 };
1106 static const int transH
[] = { 0, 0, 3, 0 };
1107 static const int transminus
[] = { 0, 0, 0, -1 };
1108 if (c
== 'S') i
= transS
[i
];
1109 else if (c
== 'H') i
= transH
[i
];
1110 else if (c
== '-') i
= transminus
[i
];
1114 crReturn(1); /* get another character */
1117 strcpy(vstring
, "SSH-");
1121 crReturn(1); /* get another char */
1122 if (vsp
< vstring
+sizeof(vstring
)-1)
1128 } else if (i
< sizeof(version
)-1)
1135 ssh_agentfwd_enabled
= FALSE
;
1136 rdpkt2_state
.incoming_sequence
= 0;
1139 sprintf(vlog
, "Server version: %s", vstring
);
1140 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1144 * Server version "1.99" means we can choose whether we use v1
1145 * or v2 protocol. Choice is based on cfg.sshprot.
1147 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1149 * This is a v2 server. Begin v2 protocol.
1151 char *verstring
= "SSH-2.0-PuTTY";
1152 SHA_Init(&exhashbase
);
1154 * Hash our version string and their version string.
1156 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1157 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1158 sprintf(vstring
, "%s\n", verstring
);
1159 sprintf(vlog
, "We claim version: %s", verstring
);
1161 logevent("Using SSH protocol version 2");
1162 sk_write(s
, vstring
, strlen(vstring
));
1163 ssh_protocol
= ssh2_protocol
;
1165 s_rdpkt
= ssh2_rdpkt
;
1168 * This is a v1 server. Begin v1 protocol.
1170 sprintf(vstring
, "SSH-%s-PuTTY\n",
1171 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1172 sprintf(vlog
, "We claim version: %s", vstring
);
1173 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1175 logevent("Using SSH protocol version 1");
1176 sk_write(s
, vstring
, strlen(vstring
));
1177 ssh_protocol
= ssh1_protocol
;
1179 s_rdpkt
= ssh1_rdpkt
;
1181 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1186 static void ssh_gotdata(unsigned char *data
, int datalen
)
1191 * To begin with, feed the characters one by one to the
1192 * protocol initialisation / selection function do_ssh_init().
1193 * When that returns 0, we're done with the initial greeting
1194 * exchange and can move on to packet discipline.
1199 crReturnV
; /* more data please */
1200 ret
= do_ssh_init(*data
);
1207 * We emerge from that loop when the initial negotiation is
1208 * over and we have selected an s_rdpkt function. Now pass
1209 * everything to s_rdpkt, and then pass the resulting packets
1210 * to the proper protocol handler.
1215 while (datalen
> 0) {
1216 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1217 ssh_protocol(NULL
, 0, 1);
1218 if (ssh_state
== SSH_STATE_CLOSED
) {
1228 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1230 /* A socket error has occurred. */
1231 ssh_state
= SSH_STATE_CLOSED
;
1234 connection_fatal(data
);
1237 /* Connection has closed. */
1238 ssh_state
= SSH_STATE_CLOSED
;
1243 ssh_gotdata (data
, len
);
1244 if (ssh_state
== SSH_STATE_CLOSED
) {
1255 * Connect to specified host and port.
1256 * Returns an error message, or NULL on success.
1257 * Also places the canonical host name into `realhost'.
1259 static char *connect_to_host(char *host
, int port
, char **realhost
)
1268 savedhost
= smalloc(1+strlen(host
));
1270 fatalbox("Out of memory");
1271 strcpy(savedhost
, host
);
1274 port
= 22; /* default ssh port */
1287 addr
= sk_namelookup(host
, realhost
);
1288 if ( (err
= sk_addr_error(addr
)) )
1298 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1299 if ( (err
= sk_socket_error(s
)) )
1303 sk_write(s
, "connect ", 8);
1304 sk_write(s
, FWhost
, strlen(FWhost
));
1307 sprintf(buf
, " %d\n", FWport
);
1308 sk_write(s
, buf
, strlen(buf
));
1316 * Handle the key exchange and user authentication phases.
1318 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1321 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1322 unsigned char cookie
[8];
1323 struct RSAKey servkey
, hostkey
;
1324 struct MD5Context md5c
;
1325 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1326 static int tried_publickey
;
1327 static unsigned char session_id
[16];
1329 static char username
[100];
1333 if (!ispkt
) crWaitUntil(ispkt
);
1335 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1336 bombout(("Public key packet not received"));
1340 logevent("Received public keys");
1342 memcpy(cookie
, pktin
.body
, 8);
1344 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1345 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1348 * Log the host key fingerprint.
1352 logevent("Host key fingerprint is:");
1353 strcpy(logmsg
, " ");
1354 hostkey
.comment
= NULL
;
1355 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1360 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1361 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1364 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1365 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1366 MD5Update(&md5c
, pktin
.body
, 8);
1367 MD5Final(session_id
, &md5c
);
1369 for (i
=0; i
<32; i
++)
1370 session_key
[i
] = random_byte();
1372 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1374 rsabuf
= smalloc(len
);
1376 fatalbox("Out of memory");
1379 * Verify the host key.
1383 * First format the key into a string.
1385 int len
= rsastr_len(&hostkey
);
1386 char fingerprint
[100];
1387 char *keystr
= smalloc(len
);
1389 fatalbox("Out of memory");
1390 rsastr_fmt(keystr
, &hostkey
);
1391 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1392 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1396 for (i
=0; i
<32; i
++) {
1397 rsabuf
[i
] = session_key
[i
];
1399 rsabuf
[i
] ^= session_id
[i
];
1402 if (hostkey
.bytes
> servkey
.bytes
) {
1403 rsaencrypt(rsabuf
, 32, &servkey
);
1404 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1406 rsaencrypt(rsabuf
, 32, &hostkey
);
1407 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1410 logevent("Encrypted session key");
1412 switch (cfg
.cipher
) {
1413 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
; break;
1414 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
; break;
1415 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
; break;
1417 c_write_str("AES not supported in SSH1, falling back to 3DES\r\n");
1418 cipher_type
= SSH_CIPHER_3DES
;
1421 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1422 c_write_str("Selected cipher not supported, falling back to 3DES\r\n");
1423 cipher_type
= SSH_CIPHER_3DES
;
1425 switch (cipher_type
) {
1426 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1427 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1428 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1431 send_packet(SSH1_CMSG_SESSION_KEY
,
1432 PKT_CHAR
, cipher_type
,
1433 PKT_DATA
, cookie
, 8,
1434 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1435 PKT_DATA
, rsabuf
, len
,
1439 logevent("Trying to enable encryption...");
1443 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1444 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1446 cipher
->sesskey(session_key
);
1450 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1451 bombout(("Encryption not successfully enabled"));
1455 logevent("Successfully started encryption");
1461 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1462 c_write_str("login as: ");
1465 crWaitUntil(!ispkt
);
1466 while (inlen
--) switch (c
= *in
++) {
1473 c_write_str("\b \b");
1479 c_write_str("\b \b");
1488 if (((c
>= ' ' && c
<= '~') ||
1489 ((unsigned char)c
>= 160)) && pos
< 40) {
1490 username
[pos
++] = c
;
1496 c_write_str("\r\n");
1497 username
[strcspn(username
, "\n\r")] = '\0';
1499 strncpy(username
, cfg
.username
, 99);
1500 username
[99] = '\0';
1503 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1505 char userlog
[22+sizeof(username
)];
1506 sprintf(userlog
, "Sent username \"%s\"", username
);
1508 if (flags
& FLAG_INTERACTIVE
&&
1509 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1510 strcat(userlog
, "\r\n");
1511 c_write_str(userlog
);
1518 tried_publickey
= 0;
1520 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1521 static char password
[100];
1522 static char prompt
[200];
1525 static int pwpkt_type
;
1527 * Show password prompt, having first obtained it via a TIS
1528 * or CryptoCard exchange if we're doing TIS or CryptoCard
1531 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1532 if (agent_exists()) {
1534 * Attempt RSA authentication using Pageant.
1536 static unsigned char request
[5], *response
, *p
;
1537 static int responselen
;
1538 static int i
, nkeys
;
1539 static int authed
= FALSE
;
1542 logevent("Pageant is running. Requesting keys.");
1544 /* Request the keys held by the agent. */
1545 PUT_32BIT(request
, 1);
1546 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
1547 agent_query(request
, 5, &r
, &responselen
);
1548 response
= (unsigned char *)r
;
1551 nkeys
= GET_32BIT(p
); p
+= 4;
1552 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1554 for (i
= 0; i
< nkeys
; i
++) {
1555 static struct RSAKey key
;
1556 static Bignum challenge
;
1557 static char *commentp
;
1558 static int commentlen
;
1560 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1563 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1564 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1565 commentlen
= GET_32BIT(p
); p
+= 4;
1566 commentp
= p
; p
+= commentlen
;
1567 send_packet(SSH1_CMSG_AUTH_RSA
,
1568 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1570 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1571 logevent("Key refused");
1574 logevent("Received RSA challenge");
1575 ssh1_read_bignum(pktin
.body
, &challenge
);
1577 char *agentreq
, *q
, *ret
;
1579 len
= 1 + 4; /* message type, bit count */
1580 len
+= ssh1_bignum_length(key
.exponent
);
1581 len
+= ssh1_bignum_length(key
.modulus
);
1582 len
+= ssh1_bignum_length(challenge
);
1583 len
+= 16; /* session id */
1584 len
+= 4; /* response format */
1585 agentreq
= smalloc(4 + len
);
1586 PUT_32BIT(agentreq
, len
);
1588 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
1589 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1591 q
+= ssh1_write_bignum(q
, key
.exponent
);
1592 q
+= ssh1_write_bignum(q
, key
.modulus
);
1593 q
+= ssh1_write_bignum(q
, challenge
);
1594 memcpy(q
, session_id
, 16); q
+= 16;
1595 PUT_32BIT(q
, 1); /* response format */
1596 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1599 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
1600 logevent("Sending Pageant's response");
1601 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1602 PKT_DATA
, ret
+5, 16, PKT_END
);
1605 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1606 logevent("Pageant's response accepted");
1607 if (flags
& FLAG_VERBOSE
) {
1608 c_write_str("Authenticated using RSA key \"");
1609 c_write(commentp
, commentlen
);
1610 c_write_str("\" from agent\r\n");
1614 logevent("Pageant's response not accepted");
1616 logevent("Pageant failed to answer challenge");
1620 logevent("No reply received from Pageant");
1623 freebn(key
.exponent
);
1624 freebn(key
.modulus
);
1633 if (*cfg
.keyfile
&& !tried_publickey
)
1634 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1636 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1638 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1639 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1640 logevent("Requested TIS authentication");
1641 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1643 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1644 logevent("TIS authentication declined");
1645 if (flags
& FLAG_INTERACTIVE
)
1646 c_write_str("TIS authentication refused.\r\n");
1648 int challengelen
= ((pktin
.body
[0] << 24) |
1649 (pktin
.body
[1] << 16) |
1650 (pktin
.body
[2] << 8) |
1652 logevent("Received TIS challenge");
1653 if (challengelen
> sizeof(prompt
)-1)
1654 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1655 memcpy(prompt
, pktin
.body
+4, challengelen
);
1656 prompt
[challengelen
] = '\0';
1659 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1661 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1662 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1663 logevent("Requested CryptoCard authentication");
1664 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1666 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1667 logevent("CryptoCard authentication declined");
1668 c_write_str("CryptoCard authentication refused.\r\n");
1670 int challengelen
= ((pktin
.body
[0] << 24) |
1671 (pktin
.body
[1] << 16) |
1672 (pktin
.body
[2] << 8) |
1674 logevent("Received CryptoCard challenge");
1675 if (challengelen
> sizeof(prompt
)-1)
1676 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1677 memcpy(prompt
, pktin
.body
+4, challengelen
);
1678 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1679 sizeof(prompt
)-challengelen
);
1680 prompt
[sizeof(prompt
)-1] = '\0';
1683 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1684 sprintf(prompt
, "%.90s@%.90s's password: ",
1685 username
, savedhost
);
1687 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1688 char *comment
= NULL
;
1689 if (flags
& FLAG_VERBOSE
)
1690 c_write_str("Trying public key authentication.\r\n");
1691 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1692 if (flags
& FLAG_VERBOSE
)
1693 c_write_str("No passphrase required.\r\n");
1696 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1700 if (ssh_get_password
) {
1701 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1703 * get_password failed to get a password (for
1704 * example because one was supplied on the command
1705 * line which has already failed to work).
1708 logevent("No more passwords to try");
1709 ssh_state
= SSH_STATE_CLOSED
;
1713 c_write_str(prompt
);
1717 crWaitUntil(!ispkt
);
1718 while (inlen
--) switch (c
= *in
++) {
1735 if (((c
>= ' ' && c
<= '~') ||
1736 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1737 password
[pos
++] = c
;
1741 c_write_str("\r\n");
1745 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1747 * Try public key authentication with the specified
1750 static struct RSAKey pubkey
;
1751 static Bignum challenge
, response
;
1753 static unsigned char buffer
[32];
1755 tried_publickey
= 1;
1756 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
1758 c_write_str("Couldn't load public key from ");
1759 c_write_str(cfg
.keyfile
);
1760 c_write_str(".\r\n");
1761 continue; /* go and try password */
1764 c_write_str("Wrong passphrase.\r\n");
1765 tried_publickey
= 0;
1766 continue; /* try again */
1770 * Send a public key attempt.
1772 send_packet(SSH1_CMSG_AUTH_RSA
,
1773 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1776 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1777 c_write_str("Server refused our public key.\r\n");
1778 continue; /* go and try password */
1780 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1781 bombout(("Bizarre response to offer of public key"));
1784 ssh1_read_bignum(pktin
.body
, &challenge
);
1785 response
= rsadecrypt(challenge
, &pubkey
);
1786 freebn(pubkey
.private_exponent
); /* burn the evidence */
1788 for (i
= 0; i
< 32; i
++) {
1789 buffer
[i
] = bignum_byte(response
, 31-i
);
1793 MD5Update(&md5c
, buffer
, 32);
1794 MD5Update(&md5c
, session_id
, 16);
1795 MD5Final(buffer
, &md5c
);
1797 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1798 PKT_DATA
, buffer
, 16, PKT_END
);
1801 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1802 if (flags
& FLAG_VERBOSE
)
1803 c_write_str("Failed to authenticate with our public key.\r\n");
1804 continue; /* go and try password */
1805 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1806 bombout(("Bizarre response to RSA authentication response"));
1810 break; /* we're through! */
1812 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1814 * Defence against traffic analysis: we send a
1815 * whole bunch of packets containing strings of
1816 * different lengths. One of these strings is the
1817 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
1818 * The others are all random data in
1819 * SSH1_MSG_IGNORE packets. This way a passive
1820 * listener can't tell which is the password, and
1821 * hence can't deduce the password length.
1823 * Anybody with a password length greater than 16
1824 * bytes is going to have enough entropy in their
1825 * password that a listener won't find it _that_
1826 * much help to know how long it is. So what we'll
1829 * - if password length < 16, we send 15 packets
1830 * containing string lengths 1 through 15
1832 * - otherwise, we let N be the nearest multiple
1833 * of 8 below the password length, and send 8
1834 * packets containing string lengths N through
1835 * N+7. This won't obscure the order of
1836 * magnitude of the password length, but it will
1837 * introduce a bit of extra uncertainty.
1839 int bottom
, top
, pwlen
, i
;
1842 pwlen
= strlen(password
);
1847 bottom
= pwlen
&~ 7;
1851 assert(pwlen
>= bottom
&& pwlen
<= top
);
1853 randomstr
= smalloc(top
+1);
1855 for (i
= bottom
; i
<= top
; i
++) {
1857 defer_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1859 for (j
= 0; j
< i
; j
++) {
1861 randomstr
[j
] = random_byte();
1862 } while (randomstr
[j
] == '\0');
1864 randomstr
[i
] = '\0';
1865 defer_packet(SSH1_MSG_IGNORE
,
1866 PKT_STR
, randomstr
, PKT_END
);
1869 ssh_pkt_defersend();
1871 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1874 logevent("Sent password");
1875 memset(password
, 0, strlen(password
));
1877 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1878 if (flags
& FLAG_VERBOSE
)
1879 c_write_str("Access denied\r\n");
1880 logevent("Authentication refused");
1881 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1882 logevent("Received disconnect request");
1883 ssh_state
= SSH_STATE_CLOSED
;
1885 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1886 bombout(("Strange packet received, type %d", pktin
.type
));
1891 logevent("Authentication successful");
1896 void sshfwd_close(struct ssh_channel
*c
) {
1898 if (ssh_version
== 1) {
1899 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1901 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1902 ssh2_pkt_adduint32(c
->remoteid
);
1906 if (c
->type
== CHAN_X11
) {
1908 logevent("X11 connection terminated");
1913 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1914 if (ssh_version
== 1) {
1915 send_packet(SSH1_MSG_CHANNEL_DATA
,
1916 PKT_INT
, c
->remoteid
,
1921 ssh2_add_channel_data(c
, buf
, len
);
1926 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1931 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1934 if (ssh_state
== SSH_STATE_CLOSED
)
1937 if (cfg
.agentfwd
&& agent_exists()) {
1938 logevent("Requesting agent forwarding");
1939 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1940 do { crReturnV
; } while (!ispkt
);
1941 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1942 bombout(("Protocol confusion"));
1944 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1945 logevent("Agent forwarding refused");
1947 logevent("Agent forwarding enabled");
1948 ssh_agentfwd_enabled
= TRUE
;
1952 if (cfg
.x11_forward
) {
1953 char proto
[20], data
[64];
1954 logevent("Requesting X11 forwarding");
1955 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
1956 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
1957 PKT_STR
, proto
, PKT_STR
, data
,
1960 do { crReturnV
; } while (!ispkt
);
1961 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1962 bombout(("Protocol confusion"));
1964 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1965 logevent("X11 forwarding refused");
1967 logevent("X11 forwarding enabled");
1968 ssh_X11_fwd_enabled
= TRUE
;
1973 send_packet(SSH1_CMSG_REQUEST_PTY
,
1974 PKT_STR
, cfg
.termtype
,
1975 PKT_INT
, rows
, PKT_INT
, cols
,
1976 PKT_INT
, 0, PKT_INT
, 0,
1979 ssh_state
= SSH_STATE_INTERMED
;
1980 do { crReturnV
; } while (!ispkt
);
1981 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1982 bombout(("Protocol confusion"));
1984 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1985 c_write_str("Server refused to allocate pty\r\n");
1986 ssh_editing
= ssh_echoing
= 1;
1988 logevent("Allocated pty");
1990 ssh_editing
= ssh_echoing
= 1;
1993 if (cfg
.compression
) {
1994 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
1995 do { crReturnV
; } while (!ispkt
);
1996 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1997 bombout(("Protocol confusion"));
1999 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2000 c_write_str("Server refused to compress\r\n");
2002 logevent("Started compression");
2003 ssh1_compressing
= TRUE
;
2004 zlib_compress_init();
2005 zlib_decompress_init();
2008 if (*cfg
.remote_cmd
)
2009 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
2011 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
2012 logevent("Started session");
2014 ssh_state
= SSH_STATE_SESSION
;
2018 ssh_special(TS_EOF
);
2020 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2022 ssh_channels
= newtree234(ssh_channelcmp
);
2026 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
2027 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
2028 long len
= GET_32BIT(pktin
.body
);
2029 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
2031 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2032 ssh_state
= SSH_STATE_CLOSED
;
2033 logevent("Received disconnect request");
2035 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
2036 /* Remote side is trying to open a channel to talk to our
2037 * X-Server. Give them back a local channel number. */
2039 struct ssh_channel
*c
, *d
;
2042 logevent("Received X11 connect request");
2043 /* Refuse if X11 forwarding is disabled. */
2044 if (!ssh_X11_fwd_enabled
) {
2045 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2046 PKT_INT
, GET_32BIT(pktin
.body
),
2048 logevent("Rejected X11 connect request");
2050 c
= smalloc(sizeof(struct ssh_channel
));
2052 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
2053 logevent("opening X11 forward connection failed");
2055 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2056 PKT_INT
, GET_32BIT(pktin
.body
),
2059 logevent("opening X11 forward connection succeeded");
2060 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
2062 break; /* found a free number */
2065 c
->remoteid
= GET_32BIT(pktin
.body
);
2068 c
->type
= CHAN_X11
; /* identify channel type */
2069 add234(ssh_channels
, c
);
2070 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2071 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2073 logevent("Opened X11 forward channel");
2076 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
2077 /* Remote side is trying to open a channel to talk to our
2078 * agent. Give them back a local channel number. */
2080 struct ssh_channel
*c
;
2083 /* Refuse if agent forwarding is disabled. */
2084 if (!ssh_agentfwd_enabled
) {
2085 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2086 PKT_INT
, GET_32BIT(pktin
.body
),
2090 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
2092 break; /* found a free number */
2095 c
= smalloc(sizeof(struct ssh_channel
));
2096 c
->remoteid
= GET_32BIT(pktin
.body
);
2099 c
->type
= CHAN_AGENT
; /* identify channel type */
2100 c
->u
.a
.lensofar
= 0;
2101 add234(ssh_channels
, c
);
2102 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2103 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2106 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2107 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2108 /* Remote side closes a channel. */
2109 unsigned i
= GET_32BIT(pktin
.body
);
2110 struct ssh_channel
*c
;
2111 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2114 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2115 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2116 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2117 logevent("X11 connection closed");
2118 assert(c
->u
.x11
.s
!= NULL
);
2119 x11_close(c
->u
.x11
.s
);
2122 c
->closes
|= closetype
;
2123 if (c
->closes
== 3) {
2124 del234(ssh_channels
, c
);
2128 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2129 /* Data sent down one of our channels. */
2130 int i
= GET_32BIT(pktin
.body
);
2131 int len
= GET_32BIT(pktin
.body
+4);
2132 unsigned char *p
= pktin
.body
+8;
2133 struct ssh_channel
*c
;
2134 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2138 x11_send(c
->u
.x11
.s
, p
, len
);
2141 /* Data for an agent message. Buffer it. */
2143 if (c
->u
.a
.lensofar
< 4) {
2144 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2145 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2146 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2148 if (c
->u
.a
.lensofar
== 4) {
2149 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2150 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2151 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2153 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2154 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2155 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2156 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2158 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2159 void *reply
, *sentreply
;
2161 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2166 /* Fake SSH_AGENT_FAILURE. */
2167 sentreply
= "\0\0\0\1\5";
2170 send_packet(SSH1_MSG_CHANNEL_DATA
,
2171 PKT_INT
, c
->remoteid
,
2173 PKT_DATA
, sentreply
, replylen
,
2177 sfree(c
->u
.a
.message
);
2178 c
->u
.a
.lensofar
= 0;
2184 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2185 /* may be from EXEC_SHELL on some servers */
2186 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2187 /* may be from EXEC_SHELL on some servers
2188 * if no pty is available or in other odd cases. Ignore */
2189 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2190 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2192 bombout(("Strange packet received: type %d", pktin
.type
));
2197 int len
= min(inlen
, 512);
2198 send_packet(SSH1_CMSG_STDIN_DATA
,
2199 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2210 * Utility routine for decoding comma-separated strings in KEXINIT.
2212 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2213 int needlen
= strlen(needle
);
2216 * Is it at the start of the string?
2218 if (haylen
>= needlen
&& /* haystack is long enough */
2219 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2220 (haylen
== needlen
|| haystack
[needlen
] == ',')
2221 /* either , or EOS follows */
2225 * If not, search for the next comma and resume after that.
2226 * If no comma found, terminate.
2228 while (haylen
> 0 && *haystack
!= ',')
2229 haylen
--, haystack
++;
2232 haylen
--, haystack
++; /* skip over comma itself */
2237 * SSH2 key creation method.
2239 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2241 /* First 20 bytes. */
2244 SHA_Bytes(&s
, H
, 20);
2245 SHA_Bytes(&s
, &chr
, 1);
2246 SHA_Bytes(&s
, sessid
, 20);
2247 SHA_Final(&s
, keyspace
);
2248 /* Next 20 bytes. */
2251 SHA_Bytes(&s
, H
, 20);
2252 SHA_Bytes(&s
, keyspace
, 20);
2253 SHA_Final(&s
, keyspace
+20);
2257 * Handle the SSH2 transport layer.
2259 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2261 static int i
, j
, len
, nbits
;
2263 static Bignum p
, g
, e
, f
, K
;
2264 static int kex_init_value
, kex_reply_value
;
2265 static const struct ssh_mac
**maclist
;
2267 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
2268 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
2269 static const struct ssh_mac
*csmac_tobe
= NULL
;
2270 static const struct ssh_mac
*scmac_tobe
= NULL
;
2271 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2272 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2273 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2274 static int hostkeylen
, siglen
;
2275 static void *hkey
; /* actual host key */
2276 static unsigned char exchange_hash
[20];
2277 static unsigned char keyspace
[40];
2278 static const struct ssh2_ciphers
*preferred_cipher
;
2279 static const struct ssh_compress
*preferred_comp
;
2280 static int first_kex
;
2287 * Set up the preferred cipher and compression.
2289 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2290 preferred_cipher
= &ssh2_blowfish
;
2291 } else if (cfg
.cipher
== CIPHER_DES
) {
2292 logevent("Single DES not supported in SSH2; using 3DES");
2293 preferred_cipher
= &ssh2_3des
;
2294 } else if (cfg
.cipher
== CIPHER_3DES
) {
2295 preferred_cipher
= &ssh2_3des
;
2296 } else if (cfg
.cipher
== CIPHER_AES
) {
2297 preferred_cipher
= &ssh2_aes
;
2299 /* Shouldn't happen, but we do want to initialise to _something_. */
2300 preferred_cipher
= &ssh2_3des
;
2302 if (cfg
.compression
)
2303 preferred_comp
= &ssh_zlib
;
2305 preferred_comp
= &ssh_comp_none
;
2308 * Be prepared to work around the buggy MAC problem.
2311 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2313 maclist
= macs
, nmacs
= lenof(macs
);
2317 * Construct and send our key exchange packet.
2319 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2320 for (i
= 0; i
< 16; i
++)
2321 ssh2_pkt_addbyte((unsigned char)random_byte());
2322 /* List key exchange algorithms. */
2323 ssh2_pkt_addstring_start();
2324 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2325 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2326 if (i
< lenof(kex_algs
)-1)
2327 ssh2_pkt_addstring_str(",");
2329 /* List server host key algorithms. */
2330 ssh2_pkt_addstring_start();
2331 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2332 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2333 if (i
< lenof(hostkey_algs
)-1)
2334 ssh2_pkt_addstring_str(",");
2336 /* List client->server encryption algorithms. */
2337 ssh2_pkt_addstring_start();
2338 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2339 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2340 for (j
= 0; j
< c
->nciphers
; j
++) {
2341 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2342 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2343 ssh2_pkt_addstring_str(",");
2346 /* List server->client encryption algorithms. */
2347 ssh2_pkt_addstring_start();
2348 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2349 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2350 for (j
= 0; j
< c
->nciphers
; j
++) {
2351 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2352 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2353 ssh2_pkt_addstring_str(",");
2356 /* List client->server MAC algorithms. */
2357 ssh2_pkt_addstring_start();
2358 for (i
= 0; i
< nmacs
; i
++) {
2359 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2361 ssh2_pkt_addstring_str(",");
2363 /* List server->client MAC algorithms. */
2364 ssh2_pkt_addstring_start();
2365 for (i
= 0; i
< nmacs
; i
++) {
2366 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2368 ssh2_pkt_addstring_str(",");
2370 /* List client->server compression algorithms. */
2371 ssh2_pkt_addstring_start();
2372 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2373 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2374 ssh2_pkt_addstring_str(c
->name
);
2375 if (i
< lenof(compressions
))
2376 ssh2_pkt_addstring_str(",");
2378 /* List server->client compression algorithms. */
2379 ssh2_pkt_addstring_start();
2380 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2381 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2382 ssh2_pkt_addstring_str(c
->name
);
2383 if (i
< lenof(compressions
))
2384 ssh2_pkt_addstring_str(",");
2386 /* List client->server languages. Empty list. */
2387 ssh2_pkt_addstring_start();
2388 /* List server->client languages. Empty list. */
2389 ssh2_pkt_addstring_start();
2390 /* First KEX packet does _not_ follow, because we're not that brave. */
2391 ssh2_pkt_addbool(FALSE
);
2393 ssh2_pkt_adduint32(0);
2395 exhash
= exhashbase
;
2396 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2400 if (!ispkt
) crWaitUntil(ispkt
);
2401 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2404 * Now examine the other side's KEXINIT to see what we're up
2407 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2408 bombout(("expected key exchange packet from server"));
2411 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2412 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2413 pktin
.savedpos
+= 16; /* skip garbage cookie */
2414 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2415 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2416 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2421 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2422 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2423 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2424 hostkey
= hostkey_algs
[i
];
2428 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2429 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2430 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2431 for (j
= 0; j
< c
->nciphers
; j
++) {
2432 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2433 cscipher_tobe
= c
->list
[j
];
2440 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2441 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2442 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2443 for (j
= 0; j
< c
->nciphers
; j
++) {
2444 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2445 sccipher_tobe
= c
->list
[j
];
2452 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2453 for (i
= 0; i
< nmacs
; i
++) {
2454 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2455 csmac_tobe
= maclist
[i
];
2459 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2460 for (i
= 0; i
< nmacs
; i
++) {
2461 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2462 scmac_tobe
= maclist
[i
];
2466 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2467 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2468 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2469 if (in_commasep_string(c
->name
, str
, len
)) {
2474 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2475 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2476 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2477 if (in_commasep_string(c
->name
, str
, len
)) {
2484 * If we're doing Diffie-Hellman group exchange, start by
2485 * requesting a group.
2487 if (kex
== &ssh_diffiehellman_gex
) {
2490 logevent("Doing Diffie-Hellman group exchange");
2492 * Work out number of bits. We start with the maximum key
2493 * length of either cipher...
2495 csbits
= cscipher_tobe
->keylen
;
2496 scbits
= sccipher_tobe
->keylen
;
2497 nbits
= (csbits
> scbits ? csbits
: scbits
);
2498 /* The keys only have 160-bit entropy, since they're based on
2499 * a SHA-1 hash. So cap the key size at 160 bits. */
2500 if (nbits
> 160) nbits
= 160;
2502 * ... and then work out how big a DH group we will need to
2503 * allow that much data.
2505 nbits
= 512 << ((nbits
-1) / 64);
2506 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
2507 ssh2_pkt_adduint32(nbits
);
2511 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
2512 bombout(("expected key exchange group packet from server"));
2515 p
= ssh2_pkt_getmp();
2516 g
= ssh2_pkt_getmp();
2517 dh_setup_group(p
, g
);
2518 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
2519 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
2522 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
2523 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
2526 logevent("Doing Diffie-Hellman key exchange");
2528 * Now generate and send e for Diffie-Hellman.
2531 ssh2_pkt_init(kex_init_value
);
2536 if (pktin
.type
!= kex_reply_value
) {
2537 bombout(("expected key exchange reply packet from server"));
2540 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2541 f
= ssh2_pkt_getmp();
2542 ssh2_pkt_getstring(&sigdata
, &siglen
);
2546 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2547 if (kex
== &ssh_diffiehellman_gex
) {
2548 sha_uint32(&exhash
, nbits
);
2549 sha_mpint(&exhash
, p
);
2550 sha_mpint(&exhash
, g
);
2552 sha_mpint(&exhash
, e
);
2553 sha_mpint(&exhash
, f
);
2554 sha_mpint(&exhash
, K
);
2555 SHA_Final(&exhash
, exchange_hash
);
2560 debug(("Exchange hash is:\r\n"));
2561 for (i
= 0; i
< 20; i
++)
2562 debug((" %02x", exchange_hash
[i
]));
2566 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2567 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2568 bombout(("Server failed host key check"));
2573 * Expect SSH2_MSG_NEWKEYS from server.
2576 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2577 bombout(("expected new-keys packet from server"));
2582 * Authenticate remote host: verify host key. (We've already
2583 * checked the signature of the exchange hash.)
2585 keystr
= hostkey
->fmtkey(hkey
);
2586 fingerprint
= hostkey
->fingerprint(hkey
);
2587 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2588 keystr
, fingerprint
);
2589 if (first_kex
) { /* don't bother logging this in rekeys */
2590 logevent("Host key fingerprint is:");
2591 logevent(fingerprint
);
2595 hostkey
->freekey(hkey
);
2598 * Send SSH2_MSG_NEWKEYS.
2600 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2604 * Create and initialise session keys.
2606 cscipher
= cscipher_tobe
;
2607 sccipher
= sccipher_tobe
;
2610 cscomp
= cscomp_tobe
;
2611 sccomp
= sccomp_tobe
;
2612 cscomp
->compress_init();
2613 sccomp
->decompress_init();
2615 * Set IVs after keys. Here we use the exchange hash from the
2616 * _first_ key exchange.
2619 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
2620 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
2621 cscipher
->setcskey(keyspace
);
2622 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
2623 sccipher
->setsckey(keyspace
);
2624 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
2625 cscipher
->setcsiv(keyspace
);
2626 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
2627 sccipher
->setsciv(keyspace
);
2628 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
2629 csmac
->setcskey(keyspace
);
2630 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
2631 scmac
->setsckey(keyspace
);
2634 * If this is the first key exchange phase, we must pass the
2635 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2636 * wants to see it but because it will need time to initialise
2637 * itself before it sees an actual packet. In subsequent key
2638 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2639 * it would only confuse the layer above.
2647 * Now we're encrypting. Begin returning 1 to the protocol main
2648 * function so that other things can run on top of the
2649 * transport. If we ever see a KEXINIT, we must go back to the
2652 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2655 logevent("Server initiated key re-exchange");
2656 goto begin_key_exchange
;
2662 * Add data to an SSH2 channel output buffer.
2664 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2665 if (c
->v2
.outbufsize
<
2666 c
->v2
.outbuflen
+ len
) {
2668 c
->v2
.outbuflen
+ len
+ 1024;
2669 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2672 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2674 c
->v2
.outbuflen
+= len
;
2678 * Attempt to send data on an SSH2 channel.
2680 static void ssh2_try_send(struct ssh_channel
*c
) {
2681 while (c
->v2
.remwindow
> 0 &&
2682 c
->v2
.outbuflen
> 0) {
2683 unsigned len
= c
->v2
.remwindow
;
2684 if (len
> c
->v2
.outbuflen
)
2685 len
= c
->v2
.outbuflen
;
2686 if (len
> c
->v2
.remmaxpkt
)
2687 len
= c
->v2
.remmaxpkt
;
2688 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2689 ssh2_pkt_adduint32(c
->remoteid
);
2690 ssh2_pkt_addstring_start();
2691 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2693 c
->v2
.outbuflen
-= len
;
2694 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2696 c
->v2
.remwindow
-= len
;
2701 * Handle the SSH2 userauth and connection layers.
2703 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2705 static unsigned long remote_winsize
;
2706 static unsigned long remote_maxpkt
;
2708 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
, AUTH_PASSWORD
2712 AUTH_TYPE_PUBLICKEY
,
2713 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
2714 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
2717 static int gotit
, need_pw
, can_pubkey
, can_passwd
;
2718 static int tried_pubkey_config
, tried_agent
;
2719 static int we_are_in
;
2720 static char username
[100];
2721 static char pwprompt
[200];
2722 static char password
[100];
2727 * Request userauth protocol, and await a response to it.
2729 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2730 ssh2_pkt_addstring("ssh-userauth");
2732 crWaitUntilV(ispkt
);
2733 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2734 bombout(("Server refused user authentication protocol"));
2739 * We repeat this whole loop, including the username prompt,
2740 * until we manage a successful authentication. If the user
2741 * types the wrong _password_, they are sent back to the
2742 * beginning to try another username. (If they specify a
2743 * username in the config, they are never asked, even if they
2744 * do give a wrong password.)
2746 * I think this best serves the needs of
2748 * - the people who have no configuration, no keys, and just
2749 * want to try repeated (username,password) pairs until they
2750 * type both correctly
2752 * - people who have keys and configuration but occasionally
2753 * need to fall back to passwords
2755 * - people with a key held in Pageant, who might not have
2756 * logged in to a particular machine before; so they want to
2757 * type a username, and then _either_ their key will be
2758 * accepted, _or_ they will type a password. If they mistype
2759 * the username they will want to be able to get back and
2770 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2771 c_write_str("login as: ");
2774 crWaitUntilV(!ispkt
);
2775 while (inlen
--) switch (c
= *in
++) {
2782 c_write_str("\b \b");
2788 c_write_str("\b \b");
2797 if (((c
>= ' ' && c
<= '~') ||
2798 ((unsigned char)c
>= 160)) && pos
< 40) {
2799 username
[pos
++] = c
;
2805 c_write_str("\r\n");
2806 username
[strcspn(username
, "\n\r")] = '\0';
2809 strncpy(username
, cfg
.username
, 99);
2810 username
[99] = '\0';
2811 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2812 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2818 * Send an authentication request using method "none": (a)
2819 * just in case it succeeds, and (b) so that we know what
2820 * authentication methods we can usefully try next.
2822 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2823 ssh2_pkt_addstring(username
);
2824 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2825 ssh2_pkt_addstring("none"); /* method */
2827 type
= AUTH_TYPE_NONE
;
2831 tried_pubkey_config
= FALSE
;
2832 tried_agent
= FALSE
;
2836 * Wait for the result of the last authentication request.
2839 crWaitUntilV(ispkt
);
2840 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
2841 /* FIXME: should support this */
2842 crWaitUntilV(ispkt
);
2844 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
2845 logevent("Access granted");
2850 if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
2851 bombout(("Strange packet received during authentication: type %d",
2858 * OK, we're now sitting on a USERAUTH_FAILURE message, so
2859 * we can look at the string in it and know what we can
2860 * helpfully try next.
2865 ssh2_pkt_getstring(&methods
, &methlen
);
2866 if (!ssh2_pkt_getbool()) {
2868 * We have received an unequivocal Access
2869 * Denied. This can translate to a variety of
2872 * - if we'd just tried "none" authentication,
2873 * it's not worth printing anything at all
2875 * - if we'd just tried a public key _offer_,
2876 * the message should be "Server refused our
2877 * key" (or no message at all if the key
2878 * came from Pageant)
2880 * - if we'd just tried anything else, the
2881 * message really should be "Access denied".
2883 * Additionally, if we'd just tried password
2884 * authentication, we should break out of this
2885 * whole loop so as to go back to the username
2888 if (type
== AUTH_TYPE_NONE
) {
2890 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
2891 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
2892 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
2893 c_write_str("Server refused our key\r\n");
2894 logevent("Server refused public key");
2896 c_write_str("Access denied\r\n");
2897 logevent("Access denied");
2898 if (type
== AUTH_TYPE_PASSWORD
) {
2904 c_write_str("Further authentication required\r\n");
2905 logevent("Further authentication required");
2908 can_pubkey
= in_commasep_string("publickey", methods
, methlen
);
2909 can_passwd
= in_commasep_string("password", methods
, methlen
);
2914 if (!method
&& can_pubkey
&& agent_exists
&& !tried_agent
) {
2916 * Attempt public-key authentication using Pageant.
2918 static unsigned char request
[5], *response
, *p
;
2919 static int responselen
;
2920 static int i
, nkeys
;
2921 static int authed
= FALSE
;
2926 logevent("Pageant is running. Requesting keys.");
2928 /* Request the keys held by the agent. */
2929 PUT_32BIT(request
, 1);
2930 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
2931 agent_query(request
, 5, &r
, &responselen
);
2932 response
= (unsigned char *)r
;
2935 nkeys
= GET_32BIT(p
); p
+= 4;
2936 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
2938 for (i
= 0; i
< nkeys
; i
++) {
2939 static char *pkblob
, *alg
, *commentp
;
2940 static int pklen
, alglen
, commentlen
;
2941 static int siglen
, retlen
, len
;
2942 static char *q
, *agentreq
, *ret
;
2944 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
2946 pklen
= GET_32BIT(p
); p
+= 4;
2947 pkblob
= p
; p
+= pklen
;
2948 alglen
= GET_32BIT(pkblob
);
2950 commentlen
= GET_32BIT(p
); p
+= 4;
2951 commentp
= p
; p
+= commentlen
;
2952 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2953 ssh2_pkt_addstring(username
);
2954 ssh2_pkt_addstring("ssh-connection");/* service requested */
2955 ssh2_pkt_addstring("publickey");/* method */
2956 ssh2_pkt_addbool(FALSE
); /* no signature included */
2957 ssh2_pkt_addstring_start();
2958 ssh2_pkt_addstring_data(alg
, alglen
);
2959 ssh2_pkt_addstring_start();
2960 ssh2_pkt_addstring_data(pkblob
, pklen
);
2963 crWaitUntilV(ispkt
);
2964 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
2965 logevent("Key refused");
2969 c_write_str("Authenticating with public key \"");
2970 c_write(commentp
, commentlen
);
2971 c_write_str("\" from agent\r\n");
2974 * Server is willing to accept the key.
2975 * Construct a SIGN_REQUEST.
2977 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2978 ssh2_pkt_addstring(username
);
2979 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2980 ssh2_pkt_addstring("publickey"); /* method */
2981 ssh2_pkt_addbool(TRUE
);
2982 ssh2_pkt_addstring_start();
2983 ssh2_pkt_addstring_data(alg
, alglen
);
2984 ssh2_pkt_addstring_start();
2985 ssh2_pkt_addstring_data(pkblob
, pklen
);
2987 siglen
= pktout
.length
- 5 + 4 + 20;
2988 len
= 1; /* message type */
2989 len
+= 4 + pklen
; /* key blob */
2990 len
+= 4 + siglen
; /* data to sign */
2991 len
+= 4; /* flags */
2992 agentreq
= smalloc(4 + len
);
2993 PUT_32BIT(agentreq
, len
);
2995 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
2996 PUT_32BIT(q
, pklen
); q
+= 4;
2997 memcpy(q
, pkblob
, pklen
); q
+= pklen
;
2998 PUT_32BIT(q
, siglen
); q
+= 4;
2999 /* Now the data to be signed... */
3000 PUT_32BIT(q
, 20); q
+= 4;
3001 memcpy(q
, ssh2_session_id
, 20); q
+= 20;
3002 memcpy(q
, pktout
.data
+5, pktout
.length
-5);
3003 q
+= pktout
.length
-5;
3004 /* And finally the (zero) flags word. */
3006 agent_query(agentreq
, len
+4, &ret
, &retlen
);
3009 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
3010 logevent("Sending Pageant's response");
3011 ssh2_pkt_addstring_start();
3012 ssh2_pkt_addstring_data(ret
+9, GET_32BIT(ret
+5));
3017 logevent("Pageant failed to answer challenge");
3027 if (!method
&& can_pubkey
&& *cfg
.keyfile
&& !tried_pubkey_config
) {
3028 unsigned char *pub_blob
;
3029 char *algorithm
, *comment
;
3032 tried_pubkey_config
= TRUE
;
3035 * Try the public key supplied in the configuration.
3037 * First, offer the public blob to see if the server is
3038 * willing to accept it.
3040 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
3043 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3044 ssh2_pkt_addstring(username
);
3045 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3046 ssh2_pkt_addstring("publickey");/* method */
3047 ssh2_pkt_addbool(FALSE
); /* no signature included */
3048 ssh2_pkt_addstring(algorithm
);
3049 ssh2_pkt_addstring_start();
3050 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
3052 logevent("Offered public key"); /* FIXME */
3054 crWaitUntilV(ispkt
);
3055 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
3057 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
3058 continue; /* key refused; give up on it */
3061 logevent("Offer of public key accepted");
3063 * Actually attempt a serious authentication using
3066 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
3067 sprintf(pwprompt
, "Passphrase for key \"%.100s\": ", comment
);
3072 c_write_str("Authenticating with public key \"");
3073 c_write_str(comment
);
3074 c_write_str("\"\r\n");
3075 method
= AUTH_PUBLICKEY_FILE
;
3079 if (!method
&& can_passwd
) {
3080 method
= AUTH_PASSWORD
;
3081 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
, savedhost
);
3086 if (ssh_get_password
) {
3087 if (!ssh_get_password(pwprompt
, password
, sizeof(password
))) {
3089 * get_password failed to get a password (for
3090 * example because one was supplied on the command
3091 * line which has already failed to work).
3094 logevent("No more passwords to try");
3095 ssh_state
= SSH_STATE_CLOSED
;
3102 c_write_str(pwprompt
);
3107 crWaitUntilV(!ispkt
);
3108 while (inlen
--) switch (c
= *in
++) {
3125 if (((c
>= ' ' && c
<= '~') ||
3126 ((unsigned char)c
>= 160)) && pos
< 40)
3127 password
[pos
++] = c
;
3131 c_write_str("\r\n");
3135 if (method
== AUTH_PUBLICKEY_FILE
) {
3137 * We have our passphrase. Now try the actual authentication.
3139 struct ssh2_userkey
*key
;
3141 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
3142 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
3143 if (key
== SSH2_WRONG_PASSPHRASE
) {
3144 c_write_str("Wrong passphrase\r\n");
3145 tried_pubkey_config
= FALSE
;
3147 c_write_str("Unable to load private key\r\n");
3148 tried_pubkey_config
= TRUE
;
3150 /* Send a spurious AUTH_NONE to return to the top. */
3151 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3152 ssh2_pkt_addstring(username
);
3153 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3154 ssh2_pkt_addstring("none"); /* method */
3156 type
= AUTH_TYPE_NONE
;
3158 unsigned char *blob
, *sigdata
;
3159 int blob_len
, sigdata_len
;
3162 * We have loaded the private key and the server
3163 * has announced that it's willing to accept it.
3164 * Hallelujah. Generate a signature and send it.
3166 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3167 ssh2_pkt_addstring(username
);
3168 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3169 ssh2_pkt_addstring("publickey"); /* method */
3170 ssh2_pkt_addbool(TRUE
);
3171 ssh2_pkt_addstring(key
->alg
->name
);
3172 blob
= key
->alg
->public_blob(key
->data
, &blob_len
);
3173 ssh2_pkt_addstring_start();
3174 ssh2_pkt_addstring_data(blob
, blob_len
);
3178 * The data to be signed is:
3182 * followed by everything so far placed in the
3185 sigdata_len
= pktout
.length
- 5 + 4 + 20;
3186 sigdata
= smalloc(sigdata_len
);
3187 PUT_32BIT(sigdata
, 20);
3188 memcpy(sigdata
+4, ssh2_session_id
, 20);
3189 memcpy(sigdata
+24, pktout
.data
+5, pktout
.length
-5);
3190 blob
= key
->alg
->sign(key
->data
, sigdata
, sigdata_len
, &blob_len
);
3191 ssh2_pkt_addstring_start();
3192 ssh2_pkt_addstring_data(blob
, blob_len
);
3197 type
= AUTH_TYPE_PUBLICKEY
;
3199 } else if (method
== AUTH_PASSWORD
) {
3201 * We send the password packet lumped tightly together with
3202 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
3203 * string long enough to make the total length of the two
3204 * packets constant. This should ensure that a passive
3205 * listener doing traffic analyis can't work out the length
3208 * For this to work, we need an assumption about the
3209 * maximum length of the password packet. I think 256 is
3210 * pretty conservative. Anyone using a password longer than
3211 * that probably doesn't have much to worry about from
3212 * people who find out how long their password is!
3214 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3215 ssh2_pkt_addstring(username
);
3216 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3217 ssh2_pkt_addstring("password");
3218 ssh2_pkt_addbool(FALSE
);
3219 ssh2_pkt_addstring(password
);
3222 * We'll include a string that's an exact multiple of the
3223 * cipher block size. If the cipher is NULL for some
3224 * reason, we don't do this trick at all because we gain
3230 stringlen
= (256 - deferred_len
);
3231 stringlen
+= cscipher
->blksize
- 1;
3232 stringlen
-= (stringlen
% cscipher
->blksize
);
3235 * Temporarily disable actual compression,
3236 * so we can guarantee to get this string
3237 * exactly the length we want it. The
3238 * compression-disabling routine should
3239 * return an integer indicating how many
3240 * bytes we should adjust our string length
3243 stringlen
-= cscomp
->disable_compression();
3245 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3246 ssh2_pkt_addstring_start();
3247 for (i
= 0; i
< stringlen
; i
++) {
3248 char c
= (char)random_byte();
3249 ssh2_pkt_addstring_data(&c
, 1);
3253 ssh_pkt_defersend();
3254 logevent("Sent password");
3255 type
= AUTH_TYPE_PASSWORD
;
3257 c_write_str("No supported authentication methods left to try!\r\n");
3258 logevent("No supported authentications offered. Disconnecting");
3259 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3260 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3261 ssh2_pkt_addstring("No supported authentication methods available");
3262 ssh2_pkt_addstring("en"); /* language tag */
3264 ssh_state
= SSH_STATE_CLOSED
;
3268 } while (!we_are_in
);
3271 * Now we're authenticated for the connection protocol. The
3272 * connection protocol will automatically have started at this
3273 * point; there's no need to send SERVICE_REQUEST.
3277 * So now create a channel with a session in it.
3279 mainchan
= smalloc(sizeof(struct ssh_channel
));
3280 mainchan
->localid
= 100; /* as good as any */
3281 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
3282 ssh2_pkt_addstring("session");
3283 ssh2_pkt_adduint32(mainchan
->localid
);
3284 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3285 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3287 crWaitUntilV(ispkt
);
3288 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3289 bombout(("Server refused to open a session"));
3291 /* FIXME: error data comes back in FAILURE packet */
3293 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
3294 bombout(("Server's channel confirmation cited wrong channel"));
3297 mainchan
->remoteid
= ssh2_pkt_getuint32();
3298 mainchan
->type
= CHAN_MAINSESSION
;
3299 mainchan
->closes
= 0;
3300 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
3301 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3302 mainchan
->v2
.outbuffer
= NULL
;
3303 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
3304 ssh_channels
= newtree234(ssh_channelcmp
);
3305 add234(ssh_channels
, mainchan
);
3306 logevent("Opened channel for session");
3309 * Potentially enable X11 forwarding.
3311 if (cfg
.x11_forward
) {
3312 char proto
[20], data
[64];
3313 logevent("Requesting X11 forwarding");
3314 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
3315 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3316 ssh2_pkt_adduint32(mainchan
->remoteid
);
3317 ssh2_pkt_addstring("x11-req");
3318 ssh2_pkt_addbool(1); /* want reply */
3319 ssh2_pkt_addbool(0); /* many connections */
3320 ssh2_pkt_addstring(proto
);
3321 ssh2_pkt_addstring(data
);
3322 ssh2_pkt_adduint32(0); /* screen number */
3326 crWaitUntilV(ispkt
);
3327 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3328 unsigned i
= ssh2_pkt_getuint32();
3329 struct ssh_channel
*c
;
3330 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3332 continue; /* nonexistent channel */
3333 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3335 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3337 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3338 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3339 bombout(("Server got confused by X11 forwarding request"));
3342 logevent("X11 forwarding refused");
3344 logevent("X11 forwarding enabled");
3345 ssh_X11_fwd_enabled
= TRUE
;
3350 * Potentially enable agent forwarding.
3352 if (cfg
.agentfwd
&& agent_exists()) {
3353 char proto
[20], data
[64];
3354 logevent("Requesting OpenSSH-style agent forwarding");
3355 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
3356 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3357 ssh2_pkt_adduint32(mainchan
->remoteid
);
3358 ssh2_pkt_addstring("auth-agent-req@openssh.com");
3359 ssh2_pkt_addbool(1); /* want reply */
3363 crWaitUntilV(ispkt
);
3364 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3365 unsigned i
= ssh2_pkt_getuint32();
3366 struct ssh_channel
*c
;
3367 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3369 continue; /* nonexistent channel */
3370 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3372 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3374 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3375 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3376 bombout(("Server got confused by agent forwarding request"));
3379 logevent("Agent forwarding refused");
3381 logevent("Agent forwarding enabled");
3382 ssh_agentfwd_enabled
= TRUE
;
3387 * Now allocate a pty for the session.
3390 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3391 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
3392 ssh2_pkt_addstring("pty-req");
3393 ssh2_pkt_addbool(1); /* want reply */
3394 ssh2_pkt_addstring(cfg
.termtype
);
3395 ssh2_pkt_adduint32(cols
);
3396 ssh2_pkt_adduint32(rows
);
3397 ssh2_pkt_adduint32(0); /* pixel width */
3398 ssh2_pkt_adduint32(0); /* pixel height */
3399 ssh2_pkt_addstring_start();
3400 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
3402 ssh_state
= SSH_STATE_INTERMED
;
3405 crWaitUntilV(ispkt
);
3406 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3407 unsigned i
= ssh2_pkt_getuint32();
3408 struct ssh_channel
*c
;
3409 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3411 continue; /* nonexistent channel */
3412 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3414 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3416 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3417 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3418 bombout(("Server got confused by pty request"));
3421 c_write_str("Server refused to allocate pty\r\n");
3422 ssh_editing
= ssh_echoing
= 1;
3424 logevent("Allocated pty");
3427 ssh_editing
= ssh_echoing
= 1;
3431 * Start a shell or a remote command.
3433 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3434 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
3435 if (cfg
.ssh_subsys
) {
3436 ssh2_pkt_addstring("subsystem");
3437 ssh2_pkt_addbool(1); /* want reply */
3438 ssh2_pkt_addstring(cfg
.remote_cmd
);
3439 } else if (*cfg
.remote_cmd
) {
3440 ssh2_pkt_addstring("exec");
3441 ssh2_pkt_addbool(1); /* want reply */
3442 ssh2_pkt_addstring(cfg
.remote_cmd
);
3444 ssh2_pkt_addstring("shell");
3445 ssh2_pkt_addbool(1); /* want reply */
3449 crWaitUntilV(ispkt
);
3450 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3451 unsigned i
= ssh2_pkt_getuint32();
3452 struct ssh_channel
*c
;
3453 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3455 continue; /* nonexistent channel */
3456 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3458 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3459 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3460 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3461 bombout(("Server got confused by shell/command request"));
3464 bombout(("Server refused to start a shell/command"));
3467 logevent("Started a shell/command");
3470 ssh_state
= SSH_STATE_SESSION
;
3474 ssh_special(TS_EOF
);
3479 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
3482 static int try_send
;
3486 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
3487 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
3490 unsigned i
= ssh2_pkt_getuint32();
3491 struct ssh_channel
*c
;
3492 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3494 continue; /* nonexistent channel */
3495 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
3496 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
3497 continue; /* extended but not stderr */
3498 ssh2_pkt_getstring(&data
, &length
);
3501 case CHAN_MAINSESSION
:
3502 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
3506 x11_send(c
->u
.x11
.s
, data
, length
);
3509 while (length
> 0) {
3510 if (c
->u
.a
.lensofar
< 4) {
3511 int l
= min(4 - c
->u
.a
.lensofar
, length
);
3512 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, data
, l
);
3513 data
+= l
; length
-= l
; c
->u
.a
.lensofar
+= l
;
3515 if (c
->u
.a
.lensofar
== 4) {
3516 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
3517 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3518 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3520 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
3521 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3523 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, data
, l
);
3524 data
+= l
; length
-= l
; c
->u
.a
.lensofar
+= l
;
3526 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3527 void *reply
, *sentreply
;
3529 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
3534 /* Fake SSH_AGENT_FAILURE. */
3535 sentreply
= "\0\0\0\1\5";
3538 ssh2_add_channel_data(c
, sentreply
, replylen
);
3542 sfree(c
->u
.a
.message
);
3543 c
->u
.a
.lensofar
= 0;
3549 * Enlarge the window again at the remote
3550 * side, just in case it ever runs down and
3551 * they fail to send us any more data.
3553 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3554 ssh2_pkt_adduint32(c
->remoteid
);
3555 ssh2_pkt_adduint32(length
);
3558 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
3559 ssh_state
= SSH_STATE_CLOSED
;
3560 logevent("Received disconnect message");
3562 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
3563 continue; /* exit status et al; ignore (FIXME?) */
3564 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
3565 unsigned i
= ssh2_pkt_getuint32();
3566 struct ssh_channel
*c
;
3568 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3570 continue; /* nonexistent channel */
3572 if (c
->type
== CHAN_X11
) {
3574 * Remote EOF on an X11 channel means we should
3575 * wrap up and close the channel ourselves.
3577 x11_close(c
->u
.x11
.s
);
3579 } else if (c
->type
== CHAN_AGENT
) {
3582 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
3583 unsigned i
= ssh2_pkt_getuint32();
3584 struct ssh_channel
*c
;
3587 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3589 continue; /* nonexistent channel */
3590 if (c
->closes
== 0) {
3591 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3592 ssh2_pkt_adduint32(c
->remoteid
);
3595 /* Do pre-close processing on the channel. */
3597 case CHAN_MAINSESSION
:
3598 break; /* nothing to see here, move along */
3604 del234(ssh_channels
, c
);
3605 sfree(c
->v2
.outbuffer
);
3609 * See if that was the last channel left open.
3611 c
= first234(ssh_channels
, &e
);
3613 logevent("All channels closed. Disconnecting");
3614 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3615 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3616 ssh2_pkt_addstring("All open channels closed");
3617 ssh2_pkt_addstring("en"); /* language tag */
3619 ssh_state
= SSH_STATE_CLOSED
;
3622 continue; /* remote sends close; ignore (FIXME) */
3623 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3624 unsigned i
= ssh2_pkt_getuint32();
3625 struct ssh_channel
*c
;
3626 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3628 continue; /* nonexistent channel */
3629 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3631 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3635 struct ssh_channel
*c
;
3636 ssh2_pkt_getstring(&type
, &typelen
);
3637 c
= smalloc(sizeof(struct ssh_channel
));
3639 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3640 if (!ssh_X11_fwd_enabled
)
3641 error
= "X11 forwarding is not enabled";
3642 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3643 error
= "Unable to open an X11 connection";
3647 } else if (typelen
== 22 &&
3648 !memcmp(type
, "auth-agent@openssh.com", 3)) {
3649 if (!ssh_agentfwd_enabled
)
3650 error
= "Agent forwarding is not enabled";
3652 c
->type
= CHAN_AGENT
; /* identify channel type */
3653 c
->u
.a
.lensofar
= 0;
3656 error
= "Unsupported channel type requested";
3659 c
->remoteid
= ssh2_pkt_getuint32();
3661 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3662 ssh2_pkt_adduint32(c
->remoteid
);
3663 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3664 ssh2_pkt_addstring(error
);
3665 ssh2_pkt_addstring("en"); /* language tag */
3669 struct ssh_channel
*d
;
3673 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3676 break; /* found a free number */
3681 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3682 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3683 c
->v2
.outbuffer
= NULL
;
3684 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3685 add234(ssh_channels
, c
);
3686 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3687 ssh2_pkt_adduint32(c
->remoteid
);
3688 ssh2_pkt_adduint32(c
->localid
);
3689 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3690 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3694 bombout(("Strange packet received: type %d", pktin
.type
));
3699 * We have spare data. Add it to the channel buffer.
3701 ssh2_add_channel_data(mainchan
, in
, inlen
);
3706 struct ssh_channel
*c
;
3708 * Try to send data on all channels if we can.
3710 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3719 * Handle the top-level SSH2 protocol.
3721 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3723 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3725 do_ssh2_authconn(in
, inlen
, ispkt
);
3729 * Called to set up the connection.
3731 * Returns an error message, or NULL on success.
3733 static char *ssh_init (char *host
, int port
, char **realhost
) {
3737 if(crypto_startup() == 0)
3738 return "Microsoft high encryption pack not installed!";
3745 p
= connect_to_host(host
, port
, realhost
);
3753 * Called to send data down the Telnet connection.
3755 static void ssh_send (char *buf
, int len
) {
3756 if (s
== NULL
|| ssh_protocol
== NULL
)
3759 ssh_protocol(buf
, len
, 0);
3763 * Called to set the size of the window from SSH's POV.
3765 static void ssh_size(void) {
3766 switch (ssh_state
) {
3767 case SSH_STATE_BEFORE_SIZE
:
3768 case SSH_STATE_PREPACKET
:
3769 case SSH_STATE_CLOSED
:
3770 break; /* do nothing */
3771 case SSH_STATE_INTERMED
:
3772 size_needed
= TRUE
; /* buffer for later */
3774 case SSH_STATE_SESSION
:
3776 if (ssh_version
== 1) {
3777 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3778 PKT_INT
, rows
, PKT_INT
, cols
,
3779 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3781 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3782 ssh2_pkt_adduint32(mainchan
->remoteid
);
3783 ssh2_pkt_addstring("window-change");
3784 ssh2_pkt_addbool(0);
3785 ssh2_pkt_adduint32(cols
);
3786 ssh2_pkt_adduint32(rows
);
3787 ssh2_pkt_adduint32(0);
3788 ssh2_pkt_adduint32(0);
3797 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3798 * can send an EOF and collect resulting output (e.g. `plink
3801 static void ssh_special (Telnet_Special code
) {
3802 if (code
== TS_EOF
) {
3803 if (ssh_state
!= SSH_STATE_SESSION
) {
3805 * Buffer the EOF in case we are pre-SESSION, so we can
3806 * send it as soon as we reach SESSION.
3812 if (ssh_version
== 1) {
3813 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3815 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3816 ssh2_pkt_adduint32(mainchan
->remoteid
);
3819 logevent("Sent EOF message");
3820 } else if (code
== TS_PING
) {
3821 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3823 if (ssh_version
== 1) {
3824 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3826 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3827 ssh2_pkt_addstring_start();
3835 static Socket
ssh_socket(void) { return s
; }
3837 static int ssh_sendok(void) { return ssh_send_ok
; }
3839 static int ssh_ldisc(int option
) {
3840 if (option
== LD_ECHO
) return ssh_echoing
;
3841 if (option
== LD_EDIT
) return ssh_editing
;
3845 Backend ssh_backend
= {