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 */
126 * Various remote-bug flags.
128 #define BUG_CHOKES_ON_SSH1_IGNORE 1
129 #define BUG_SSH2_HMAC 2
131 #define GET_32BIT(cp) \
132 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
133 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
134 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
135 ((unsigned long)(unsigned char)(cp)[3]))
137 #define PUT_32BIT(cp, value) { \
138 (cp)[0] = (unsigned char)((value) >> 24); \
139 (cp)[1] = (unsigned char)((value) >> 16); \
140 (cp)[2] = (unsigned char)((value) >> 8); \
141 (cp)[3] = (unsigned char)(value); }
143 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
145 /* Coroutine mechanics for the sillier bits of the code */
146 #define crBegin1 static int crLine = 0;
147 #define crBegin2 switch(crLine) { case 0:;
148 #define crBegin crBegin1; crBegin2;
149 #define crFinish(z) } crLine = 0; return (z)
150 #define crFinishV } crLine = 0; return
151 #define crReturn(z) \
153 crLine=__LINE__; return (z); case __LINE__:;\
157 crLine=__LINE__; return; case __LINE__:;\
159 #define crStop(z) do{ crLine = 0; return (z); }while(0)
160 #define crStopV do{ crLine = 0; return; }while(0)
161 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
162 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
164 extern char *x11_init (Socket
*, char *, void *);
165 extern void x11_close (Socket
);
166 extern void x11_send (Socket
, char *, int);
167 extern void x11_invent_auth(char *, int, char *, int);
170 * Ciphers for SSH2. We miss out single-DES because it isn't
171 * supported; also 3DES and Blowfish are both done differently from
172 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
173 * endianness and different-sized keys.)
175 const static struct ssh2_ciphers
*ciphers
[] = {
181 const static struct ssh_kex
*kex_algs
[] = {
182 #ifdef DO_DIFFIE_HELLMAN_GEX
183 &ssh_diffiehellman_gex
,
185 &ssh_diffiehellman
};
187 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
189 static void nullmac_key(unsigned char *key
) { }
190 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
191 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
192 const static struct ssh_mac ssh_mac_none
= {
193 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
195 const static struct ssh_mac
*macs
[] = {
196 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
197 const static struct ssh_mac
*buggymacs
[] = {
198 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
200 static void ssh_comp_none_init(void) { }
201 static int ssh_comp_none_block(unsigned char *block
, int len
,
202 unsigned char **outblock
, int *outlen
) {
205 const static struct ssh_compress ssh_comp_none
= {
207 ssh_comp_none_init
, ssh_comp_none_block
,
208 ssh_comp_none_init
, ssh_comp_none_block
210 extern const struct ssh_compress ssh_zlib
;
211 const static struct ssh_compress
*compressions
[] = {
212 &ssh_zlib
, &ssh_comp_none
};
214 enum { /* channel types */
221 * 2-3-4 tree storing channels.
224 unsigned remoteid
, localid
;
227 struct ssh2_data_channel
{
228 unsigned char *outbuffer
;
229 unsigned outbuflen
, outbufsize
;
230 unsigned remwindow
, remmaxpkt
;
233 struct ssh_agent_channel
{
234 unsigned char *message
;
235 unsigned char msglen
[4];
236 int lensofar
, totallen
;
238 struct ssh_x11_channel
{
253 static SHA_State exhash
, exhashbase
;
255 static Socket s
= NULL
;
257 static unsigned char session_key
[32];
258 static int ssh1_compressing
;
259 static int ssh_agentfwd_enabled
;
260 static int ssh_X11_fwd_enabled
;
261 static int ssh_remote_bugs
;
262 static const struct ssh_cipher
*cipher
= NULL
;
263 static const struct ssh2_cipher
*cscipher
= NULL
;
264 static const struct ssh2_cipher
*sccipher
= NULL
;
265 static const struct ssh_mac
*csmac
= NULL
;
266 static const struct ssh_mac
*scmac
= NULL
;
267 static const struct ssh_compress
*cscomp
= NULL
;
268 static const struct ssh_compress
*sccomp
= NULL
;
269 static const struct ssh_kex
*kex
= NULL
;
270 static const struct ssh_signkey
*hostkey
= NULL
;
271 static unsigned char ssh2_session_id
[20];
272 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
274 static char *savedhost
;
275 static int savedport
;
276 static int ssh_send_ok
;
277 static int ssh_echoing
, ssh_editing
;
279 static tree234
*ssh_channels
; /* indexed by local id */
280 static struct ssh_channel
*mainchan
; /* primary session channel */
284 SSH_STATE_BEFORE_SIZE
,
288 } ssh_state
= SSH_STATE_PREPACKET
;
290 static int size_needed
= FALSE
, eof_needed
= FALSE
;
292 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
293 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
294 static unsigned char *deferred_send_data
= NULL
;
295 static int deferred_len
= 0, deferred_size
= 0;
297 static int ssh_version
;
298 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
299 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
300 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
301 static void ssh_size(void);
302 static void ssh_special (Telnet_Special
);
303 static void ssh2_try_send(struct ssh_channel
*c
);
304 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
306 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
308 static struct rdpkt1_state_tag
{
309 long len
, pad
, biglen
, to_read
;
310 unsigned long realcrc
, gotcrc
;
316 static struct rdpkt2_state_tag
{
317 long len
, pad
, payload
, packetlen
, maclen
;
320 unsigned long incoming_sequence
;
323 static int ssh_channelcmp(void *av
, void *bv
) {
324 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
325 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
326 if (a
->localid
< b
->localid
) return -1;
327 if (a
->localid
> b
->localid
) return +1;
330 static int ssh_channelfind(void *av
, void *bv
) {
331 unsigned *a
= (unsigned *)av
;
332 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
333 if (*a
< b
->localid
) return -1;
334 if (*a
> b
->localid
) return +1;
338 static void c_write (char *buf
, int len
) {
339 if ((flags
& FLAG_STDERR
)) {
341 for (i
= 0; i
< len
; i
++)
343 fputc(buf
[i
], stderr
);
346 from_backend(1, buf
, len
);
349 static void c_write_str (char *buf
) {
350 c_write(buf
, strlen(buf
));
354 * Collect incoming data in the incoming packet buffer.
355 * Decipher and verify the packet when it is completely read.
356 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
357 * Update the *data and *datalen variables.
358 * Return the additional nr of bytes needed, or 0 when
359 * a complete packet is available.
361 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
363 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
372 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
373 while ((*datalen
) == 0)
375 st
->len
= (st
->len
<< 8) + **data
;
376 (*data
)++, (*datalen
)--;
380 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
381 st
->len
= 0x300; /* big enough to carry to end */
385 st
->pad
= 8 - (st
->len
% 8);
386 st
->biglen
= st
->len
+ st
->pad
;
387 pktin
.length
= st
->len
- 5;
389 if (pktin
.maxlen
< st
->biglen
) {
390 pktin
.maxlen
= st
->biglen
;
391 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->biglen
+APIEXTRA
) :
392 srealloc(pktin
.data
, st
->biglen
+APIEXTRA
));
394 fatalbox("Out of memory");
397 st
->to_read
= st
->biglen
;
399 while (st
->to_read
> 0) {
400 st
->chunk
= st
->to_read
;
401 while ((*datalen
) == 0)
402 crReturn(st
->to_read
);
403 if (st
->chunk
> (*datalen
))
404 st
->chunk
= (*datalen
);
405 memcpy(st
->p
, *data
, st
->chunk
);
407 *datalen
-= st
->chunk
;
409 st
->to_read
-= st
->chunk
;
413 cipher
->decrypt(pktin
.data
, st
->biglen
);
415 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
416 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
417 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
421 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
422 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
423 if (st
->gotcrc
!= st
->realcrc
) {
424 bombout(("Incorrect CRC received on packet"));
428 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
430 if (ssh1_compressing
) {
431 unsigned char *decompblk
;
435 debug(("Packet payload pre-decompression:\n"));
436 for (i
= -1; i
< pktin
.length
; i
++)
437 debug((" %02x", (unsigned char)pktin
.body
[i
]));
440 zlib_decompress_block(pktin
.body
-1, pktin
.length
+1,
441 &decompblk
, &decomplen
);
443 if (pktin
.maxlen
< st
->pad
+ decomplen
) {
444 pktin
.maxlen
= st
->pad
+ decomplen
;
445 pktin
.data
= srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
);
446 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
448 fatalbox("Out of memory");
451 memcpy(pktin
.body
-1, decompblk
, decomplen
);
453 pktin
.length
= decomplen
-1;
455 debug(("Packet payload post-decompression:\n"));
456 for (i
= -1; i
< pktin
.length
; i
++)
457 debug((" %02x", (unsigned char)pktin
.body
[i
]));
462 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
463 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
464 pktin
.type
== SSH1_MSG_DEBUG
||
465 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
466 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
467 long strlen
= GET_32BIT(pktin
.body
);
468 if (strlen
+ 4 != pktin
.length
) {
469 bombout(("Received data packet with bogus string length"));
474 pktin
.type
= pktin
.body
[-1];
476 if (pktin
.type
== SSH1_MSG_DEBUG
) {
477 /* log debug message */
479 int strlen
= GET_32BIT(pktin
.body
);
480 strcpy(buf
, "Remote: ");
481 if (strlen
> 70) strlen
= 70;
482 memcpy(buf
+8, pktin
.body
+4, strlen
);
483 buf
[8+strlen
] = '\0';
486 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
494 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
496 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
504 st
->cipherblk
= sccipher
->blksize
;
507 if (st
->cipherblk
< 8)
510 if (pktin
.maxlen
< st
->cipherblk
) {
511 pktin
.maxlen
= st
->cipherblk
;
512 pktin
.data
= (pktin
.data
== NULL ?
smalloc(st
->cipherblk
+APIEXTRA
) :
513 srealloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
515 fatalbox("Out of memory");
519 * Acquire and decrypt the first block of the packet. This will
520 * contain the length and padding details.
522 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
523 while ((*datalen
) == 0)
524 crReturn(st
->cipherblk
-st
->i
);
525 pktin
.data
[st
->i
] = *(*data
)++;
529 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
534 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
537 * Now get the length and padding figures.
539 st
->len
= GET_32BIT(pktin
.data
);
540 st
->pad
= pktin
.data
[4];
543 * This enables us to deduce the payload length.
545 st
->payload
= st
->len
- st
->pad
- 1;
547 pktin
.length
= st
->payload
+ 5;
550 * So now we can work out the total packet length.
552 st
->packetlen
= st
->len
+ 4;
553 st
->maclen
= scmac ? scmac
->len
: 0;
556 * Adjust memory allocation if packet is too big.
558 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
559 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
560 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
561 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
563 fatalbox("Out of memory");
567 * Read and decrypt the remainder of the packet.
569 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
570 while ((*datalen
) == 0)
571 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
572 pktin
.data
[st
->i
] = *(*data
)++;
575 /* Decrypt everything _except_ the MAC. */
577 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
578 st
->packetlen
- st
->cipherblk
);
581 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
582 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
583 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
590 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
591 bombout(("Incorrect MAC received on packet"));
594 st
->incoming_sequence
++; /* whether or not we MACed */
597 * Decompress packet payload.
600 unsigned char *newpayload
;
602 if (sccomp
&& sccomp
->decompress(pktin
.data
+5, pktin
.length
-5,
603 &newpayload
, &newlen
)) {
604 if (pktin
.maxlen
< newlen
+5) {
605 pktin
.maxlen
= newlen
+5;
606 pktin
.data
= (pktin
.data
== NULL ?
smalloc(pktin
.maxlen
+APIEXTRA
) :
607 srealloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
609 fatalbox("Out of memory");
611 pktin
.length
= 5 + newlen
;
612 memcpy(pktin
.data
+5, newpayload
, newlen
);
614 debug(("Post-decompression payload:\r\n"));
615 for (st
->i
= 0; st
->i
< newlen
; st
->i
++)
616 debug((" %02x", (unsigned char)pktin
.data
[5+st
->i
]));
625 pktin
.type
= pktin
.data
[5];
627 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
628 goto next_packet
; /* FIXME: print DEBUG message */
633 static void ssh1_pktout_size(int len
) {
636 len
+= 5; /* type and CRC */
640 pktout
.length
= len
-5;
641 if (pktout
.maxlen
< biglen
) {
642 pktout
.maxlen
= biglen
;
644 /* Allocate enough buffer space for extra block
645 * for MS CryptEncrypt() */
646 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+12) :
647 srealloc(pktout
.data
, biglen
+12));
649 pktout
.data
= (pktout
.data
== NULL ?
smalloc(biglen
+4) :
650 srealloc(pktout
.data
, biglen
+4));
653 fatalbox("Out of memory");
655 pktout
.body
= pktout
.data
+4+pad
+1;
658 static void s_wrpkt_start(int type
, int len
) {
659 ssh1_pktout_size(len
);
663 static int s_wrpkt_prepare(void) {
664 int pad
, len
, biglen
, i
;
667 pktout
.body
[-1] = pktout
.type
;
670 debug(("Packet payload pre-compression:\n"));
671 for (i
= -1; i
< pktout
.length
; i
++)
672 debug((" %02x", (unsigned char)pktout
.body
[i
]));
676 if (ssh1_compressing
) {
677 unsigned char *compblk
;
679 zlib_compress_block(pktout
.body
-1, pktout
.length
+1,
681 ssh1_pktout_size(complen
-1);
682 memcpy(pktout
.body
-1, compblk
, complen
);
685 debug(("Packet payload post-compression:\n"));
686 for (i
= -1; i
< pktout
.length
; i
++)
687 debug((" %02x", (unsigned char)pktout
.body
[i
]));
692 len
= pktout
.length
+ 5; /* type and CRC */
696 for (i
=0; i
<pad
; i
++)
697 pktout
.data
[i
+4] = random_byte();
698 crc
= crc32(pktout
.data
+4, biglen
-4);
699 PUT_32BIT(pktout
.data
+biglen
, crc
);
700 PUT_32BIT(pktout
.data
, len
);
703 debug(("Sending packet len=%d\r\n", biglen
+4));
704 for (i
= 0; i
< biglen
+4; i
++)
705 debug((" %02x", (unsigned char)pktout
.data
[i
]));
709 cipher
->encrypt(pktout
.data
+4, biglen
);
714 static void s_wrpkt(void) {
716 len
= s_wrpkt_prepare();
717 sk_write(s
, pktout
.data
, len
);
720 static void s_wrpkt_defer(void) {
722 len
= s_wrpkt_prepare();
723 if (deferred_len
+ len
> deferred_size
) {
724 deferred_size
= deferred_len
+ len
+ 128;
725 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
727 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
732 * Construct a packet with the specified contents.
734 static void construct_packet(int pkttype
, va_list ap1
, va_list ap2
)
736 unsigned char *p
, *argp
, argchar
;
737 unsigned long argint
;
738 int pktlen
, argtype
, arglen
;
742 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
745 (void) va_arg(ap1
, int);
749 (void) va_arg(ap1
, char);
753 (void) va_arg(ap1
, unsigned char *);
754 arglen
= va_arg(ap1
, int);
758 argp
= va_arg(ap1
, unsigned char *);
759 arglen
= strlen(argp
);
760 pktlen
+= 4 + arglen
;
763 bn
= va_arg(ap1
, Bignum
);
764 pktlen
+= ssh1_bignum_length(bn
);
771 s_wrpkt_start(pkttype
, pktlen
);
774 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
777 argint
= va_arg(ap2
, int);
778 PUT_32BIT(p
, argint
);
782 argchar
= va_arg(ap2
, unsigned char);
787 argp
= va_arg(ap2
, unsigned char *);
788 arglen
= va_arg(ap2
, int);
789 memcpy(p
, argp
, arglen
);
793 argp
= va_arg(ap2
, unsigned char *);
794 arglen
= strlen(argp
);
795 PUT_32BIT(p
, arglen
);
796 memcpy(p
+ 4, argp
, arglen
);
800 bn
= va_arg(ap2
, Bignum
);
801 p
+= ssh1_write_bignum(p
, bn
);
807 static void send_packet(int pkttype
, ...) {
809 va_start(ap1
, pkttype
);
810 va_start(ap2
, pkttype
);
811 construct_packet(pkttype
, ap1
, ap2
);
815 static void defer_packet(int pkttype
, ...) {
817 va_start(ap1
, pkttype
);
818 va_start(ap2
, pkttype
);
819 construct_packet(pkttype
, ap1
, ap2
);
823 static int ssh_versioncmp(char *a
, char *b
) {
825 unsigned long av
, bv
;
827 av
= strtoul(a
, &ae
, 10);
828 bv
= strtoul(b
, &be
, 10);
829 if (av
!= bv
) return (av
< bv ?
-1 : +1);
830 if (*ae
== '.') ae
++;
831 if (*be
== '.') be
++;
832 av
= strtoul(ae
, &ae
, 10);
833 bv
= strtoul(be
, &be
, 10);
834 if (av
!= bv
) return (av
< bv ?
-1 : +1);
840 * Utility routines for putting an SSH-protocol `string' and
841 * `uint32' into a SHA state.
844 static void sha_string(SHA_State
*s
, void *str
, int len
) {
845 unsigned char lenblk
[4];
846 PUT_32BIT(lenblk
, len
);
847 SHA_Bytes(s
, lenblk
, 4);
848 SHA_Bytes(s
, str
, len
);
851 static void sha_uint32(SHA_State
*s
, unsigned i
) {
852 unsigned char intblk
[4];
853 PUT_32BIT(intblk
, i
);
854 SHA_Bytes(s
, intblk
, 4);
858 * SSH2 packet construction functions.
860 static void ssh2_pkt_ensure(int length
) {
861 if (pktout
.maxlen
< length
) {
862 pktout
.maxlen
= length
+ 256;
863 pktout
.data
= (pktout
.data
== NULL ?
smalloc(pktout
.maxlen
+APIEXTRA
) :
864 srealloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
866 fatalbox("Out of memory");
869 static void ssh2_pkt_adddata(void *data
, int len
) {
870 pktout
.length
+= len
;
871 ssh2_pkt_ensure(pktout
.length
);
872 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
874 static void ssh2_pkt_addbyte(unsigned char byte
) {
875 ssh2_pkt_adddata(&byte
, 1);
877 static void ssh2_pkt_init(int pkt_type
) {
879 ssh2_pkt_addbyte((unsigned char)pkt_type
);
881 static void ssh2_pkt_addbool(unsigned char value
) {
882 ssh2_pkt_adddata(&value
, 1);
884 static void ssh2_pkt_adduint32(unsigned long value
) {
887 ssh2_pkt_adddata(x
, 4);
889 static void ssh2_pkt_addstring_start(void) {
890 ssh2_pkt_adduint32(0);
891 pktout
.savedpos
= pktout
.length
;
893 static void ssh2_pkt_addstring_str(char *data
) {
894 ssh2_pkt_adddata(data
, strlen(data
));
895 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
896 pktout
.length
- pktout
.savedpos
);
898 static void ssh2_pkt_addstring_data(char *data
, int len
) {
899 ssh2_pkt_adddata(data
, len
);
900 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
901 pktout
.length
- pktout
.savedpos
);
903 static void ssh2_pkt_addstring(char *data
) {
904 ssh2_pkt_addstring_start();
905 ssh2_pkt_addstring_str(data
);
907 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
909 int i
, n
= (ssh1_bignum_bitcount(b
)+7)/8;
912 fatalbox("out of memory");
914 for (i
= 1; i
<= n
; i
++)
915 p
[i
] = bignum_byte(b
, n
-i
);
917 while (i
<= n
&& p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
919 memmove(p
, p
+i
, n
+1-i
);
923 static void ssh2_pkt_addmp(Bignum b
) {
926 p
= ssh2_mpint_fmt(b
, &len
);
927 ssh2_pkt_addstring_start();
928 ssh2_pkt_addstring_data(p
, len
);
933 * Construct an SSH2 final-form packet: compress it, encrypt it,
934 * put the MAC on it. Final packet, ready to be sent, is stored in
935 * pktout.data. Total length is returned.
937 static int ssh2_pkt_construct(void) {
938 int cipherblk
, maclen
, padding
, i
;
939 static unsigned long outgoing_sequence
= 0;
942 * Compress packet payload.
945 debug(("Pre-compression payload:\r\n"));
946 for (i
= 5; i
< pktout
.length
; i
++)
947 debug((" %02x", (unsigned char)pktout
.data
[i
]));
951 unsigned char *newpayload
;
953 if (cscomp
&& cscomp
->compress(pktout
.data
+5, pktout
.length
-5,
954 &newpayload
, &newlen
)) {
956 ssh2_pkt_adddata(newpayload
, newlen
);
962 * Add padding. At least four bytes, and must also bring total
963 * length (minus MAC) up to a multiple of the block size.
965 cipherblk
= cscipher ? cscipher
->blksize
: 8; /* block size */
966 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
968 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
969 maclen
= csmac ? csmac
->len
: 0;
970 ssh2_pkt_ensure(pktout
.length
+ padding
+ maclen
);
971 pktout
.data
[4] = padding
;
972 for (i
= 0; i
< padding
; i
++)
973 pktout
.data
[pktout
.length
+ i
] = random_byte();
974 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
976 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
978 outgoing_sequence
++; /* whether or not we MACed */
981 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
982 for (i
= 0; i
< pktout
.length
+padding
; i
++)
983 debug((" %02x", (unsigned char)pktout
.data
[i
]));
988 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
990 /* Ready-to-send packet starts at pktout.data. We return length. */
991 return pktout
.length
+ padding
+ maclen
;
995 * Construct and send an SSH2 packet immediately.
997 static void ssh2_pkt_send(void) {
998 int len
= ssh2_pkt_construct();
999 sk_write(s
, pktout
.data
, len
);
1003 * Construct an SSH2 packet and add it to a deferred data block.
1004 * Useful for sending multiple packets in a single sk_write() call,
1005 * to prevent a traffic-analysing listener from being able to work
1006 * out the length of any particular packet (such as the password
1009 * Note that because SSH2 sequence-numbers its packets, this can
1010 * NOT be used as an m4-style `defer' allowing packets to be
1011 * constructed in one order and sent in another.
1013 static void ssh2_pkt_defer(void) {
1014 int len
= ssh2_pkt_construct();
1015 if (deferred_len
+ len
> deferred_size
) {
1016 deferred_size
= deferred_len
+ len
+ 128;
1017 deferred_send_data
= srealloc(deferred_send_data
, deferred_size
);
1019 memcpy(deferred_send_data
+deferred_len
, pktout
.data
, len
);
1020 deferred_len
+= len
;
1024 * Send the whole deferred data block constructed by
1025 * ssh2_pkt_defer() or SSH1's defer_packet().
1027 static void ssh_pkt_defersend(void) {
1028 sk_write(s
, deferred_send_data
, deferred_len
);
1029 deferred_len
= deferred_size
= 0;
1030 sfree(deferred_send_data
);
1031 deferred_send_data
= NULL
;
1035 void bndebug(char *string
, Bignum b
) {
1038 p
= ssh2_mpint_fmt(b
, &len
);
1039 debug(("%s", string
));
1040 for (i
= 0; i
< len
; i
++)
1041 debug((" %02x", p
[i
]));
1047 static void sha_mpint(SHA_State
*s
, Bignum b
) {
1050 p
= ssh2_mpint_fmt(b
, &len
);
1051 sha_string(s
, p
, len
);
1056 * SSH2 packet decode functions.
1058 static unsigned long ssh2_pkt_getuint32(void) {
1059 unsigned long value
;
1060 if (pktin
.length
- pktin
.savedpos
< 4)
1061 return 0; /* arrgh, no way to decline (FIXME?) */
1062 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1063 pktin
.savedpos
+= 4;
1066 static int ssh2_pkt_getbool(void) {
1067 unsigned long value
;
1068 if (pktin
.length
- pktin
.savedpos
< 1)
1069 return 0; /* arrgh, no way to decline (FIXME?) */
1070 value
= pktin
.data
[pktin
.savedpos
] != 0;
1074 static void ssh2_pkt_getstring(char **p
, int *length
) {
1076 if (pktin
.length
- pktin
.savedpos
< 4)
1078 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
1079 pktin
.savedpos
+= 4;
1080 if (pktin
.length
- pktin
.savedpos
< *length
)
1082 *p
= pktin
.data
+pktin
.savedpos
;
1083 pktin
.savedpos
+= *length
;
1085 static Bignum
ssh2_pkt_getmp(void) {
1090 ssh2_pkt_getstring(&p
, &length
);
1094 bombout(("internal error: Can't handle negative mpints"));
1097 b
= bignum_from_bytes(p
, length
);
1102 * Examine the remote side's version string and compare it against
1103 * a list of known buggy implementations.
1105 static void ssh_detect_bugs(char *vstring
) {
1106 char *imp
; /* pointer to implementation part */
1108 imp
+= strcspn(imp
, "-");
1109 imp
+= strcspn(imp
, "-");
1111 ssh_remote_bugs
= 0;
1113 if (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1114 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1115 !strcmp(imp
, "1.2.22")) {
1117 * These versions don't support SSH1_MSG_IGNORE, so we have
1118 * to use a different defence against password length
1121 ssh_remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1122 logevent("We believe remote version has SSH1 ignore bug");
1125 if (!strncmp(imp
, "2.1.0", 5) || !strncmp(imp
, "2.0.", 4) ||
1126 !strncmp(imp
, "2.2.0", 5) || !strncmp(imp
, "2.3.0", 5) ||
1127 !strncmp(imp
, "2.1 ", 4)) {
1129 * These versions have the HMAC bug.
1131 ssh_remote_bugs
|= BUG_SSH2_HMAC
;
1132 logevent("We believe remote version has SSH2 HMAC bug");
1136 static int do_ssh_init(unsigned char c
) {
1138 static char version
[10];
1139 static char vstring
[80];
1140 static char vlog
[sizeof(vstring
)+20];
1145 /* Search for the string "SSH-" in the input. */
1148 static const int transS
[] = { 1, 2, 2, 1 };
1149 static const int transH
[] = { 0, 0, 3, 0 };
1150 static const int transminus
[] = { 0, 0, 0, -1 };
1151 if (c
== 'S') i
= transS
[i
];
1152 else if (c
== 'H') i
= transH
[i
];
1153 else if (c
== '-') i
= transminus
[i
];
1157 crReturn(1); /* get another character */
1160 strcpy(vstring
, "SSH-");
1164 crReturn(1); /* get another char */
1165 if (vsp
< vstring
+sizeof(vstring
)-1)
1171 } else if (i
< sizeof(version
)-1)
1178 ssh_agentfwd_enabled
= FALSE
;
1179 rdpkt2_state
.incoming_sequence
= 0;
1182 sprintf(vlog
, "Server version: %s", vstring
);
1183 ssh_detect_bugs(vstring
);
1184 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1188 * Server version "1.99" means we can choose whether we use v1
1189 * or v2 protocol. Choice is based on cfg.sshprot.
1191 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1193 * This is a v2 server. Begin v2 protocol.
1195 char *verstring
= "SSH-2.0-PuTTY";
1196 SHA_Init(&exhashbase
);
1198 * Hash our version string and their version string.
1200 sha_string(&exhashbase
, verstring
, strlen(verstring
));
1201 sha_string(&exhashbase
, vstring
, strcspn(vstring
, "\r\n"));
1202 sprintf(vstring
, "%s\n", verstring
);
1203 sprintf(vlog
, "We claim version: %s", verstring
);
1205 logevent("Using SSH protocol version 2");
1206 sk_write(s
, vstring
, strlen(vstring
));
1207 ssh_protocol
= ssh2_protocol
;
1209 s_rdpkt
= ssh2_rdpkt
;
1212 * This is a v1 server. Begin v1 protocol.
1214 sprintf(vstring
, "SSH-%s-PuTTY\n",
1215 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1216 sprintf(vlog
, "We claim version: %s", vstring
);
1217 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1219 logevent("Using SSH protocol version 1");
1220 sk_write(s
, vstring
, strlen(vstring
));
1221 ssh_protocol
= ssh1_protocol
;
1223 s_rdpkt
= ssh1_rdpkt
;
1225 ssh_state
= SSH_STATE_BEFORE_SIZE
;
1230 static void ssh_gotdata(unsigned char *data
, int datalen
)
1235 * To begin with, feed the characters one by one to the
1236 * protocol initialisation / selection function do_ssh_init().
1237 * When that returns 0, we're done with the initial greeting
1238 * exchange and can move on to packet discipline.
1243 crReturnV
; /* more data please */
1244 ret
= do_ssh_init(*data
);
1251 * We emerge from that loop when the initial negotiation is
1252 * over and we have selected an s_rdpkt function. Now pass
1253 * everything to s_rdpkt, and then pass the resulting packets
1254 * to the proper protocol handler.
1259 while (datalen
> 0) {
1260 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
1261 ssh_protocol(NULL
, 0, 1);
1262 if (ssh_state
== SSH_STATE_CLOSED
) {
1272 static int ssh_receive(Socket skt
, int urgent
, char *data
, int len
) {
1274 /* A socket error has occurred. */
1275 ssh_state
= SSH_STATE_CLOSED
;
1278 connection_fatal(data
);
1281 /* Connection has closed. */
1282 ssh_state
= SSH_STATE_CLOSED
;
1287 ssh_gotdata (data
, len
);
1288 if (ssh_state
== SSH_STATE_CLOSED
) {
1299 * Connect to specified host and port.
1300 * Returns an error message, or NULL on success.
1301 * Also places the canonical host name into `realhost'.
1303 static char *connect_to_host(char *host
, int port
, char **realhost
)
1312 savedhost
= smalloc(1+strlen(host
));
1314 fatalbox("Out of memory");
1315 strcpy(savedhost
, host
);
1318 port
= 22; /* default ssh port */
1331 addr
= sk_namelookup(host
, realhost
);
1332 if ( (err
= sk_addr_error(addr
)) )
1342 s
= sk_new(addr
, port
, 0, 1, ssh_receive
);
1343 if ( (err
= sk_socket_error(s
)) )
1347 sk_write(s
, "connect ", 8);
1348 sk_write(s
, FWhost
, strlen(FWhost
));
1351 sprintf(buf
, " %d\n", FWport
);
1352 sk_write(s
, buf
, strlen(buf
));
1360 * Handle the key exchange and user authentication phases.
1362 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1365 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1366 unsigned char cookie
[8];
1367 struct RSAKey servkey
, hostkey
;
1368 struct MD5Context md5c
;
1369 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1370 static int tried_publickey
;
1371 static unsigned char session_id
[16];
1373 static char username
[100];
1377 if (!ispkt
) crWaitUntil(ispkt
);
1379 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1380 bombout(("Public key packet not received"));
1384 logevent("Received public keys");
1386 memcpy(cookie
, pktin
.body
, 8);
1388 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1389 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1392 * Log the host key fingerprint.
1396 logevent("Host key fingerprint is:");
1397 strcpy(logmsg
, " ");
1398 hostkey
.comment
= NULL
;
1399 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1404 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1405 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1408 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1409 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1410 MD5Update(&md5c
, pktin
.body
, 8);
1411 MD5Final(session_id
, &md5c
);
1413 for (i
=0; i
<32; i
++)
1414 session_key
[i
] = random_byte();
1416 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1418 rsabuf
= smalloc(len
);
1420 fatalbox("Out of memory");
1423 * Verify the host key.
1427 * First format the key into a string.
1429 int len
= rsastr_len(&hostkey
);
1430 char fingerprint
[100];
1431 char *keystr
= smalloc(len
);
1433 fatalbox("Out of memory");
1434 rsastr_fmt(keystr
, &hostkey
);
1435 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1436 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1440 for (i
=0; i
<32; i
++) {
1441 rsabuf
[i
] = session_key
[i
];
1443 rsabuf
[i
] ^= session_id
[i
];
1446 if (hostkey
.bytes
> servkey
.bytes
) {
1447 rsaencrypt(rsabuf
, 32, &servkey
);
1448 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1450 rsaencrypt(rsabuf
, 32, &hostkey
);
1451 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1454 logevent("Encrypted session key");
1456 switch (cfg
.cipher
) {
1457 case CIPHER_BLOWFISH
: cipher_type
= SSH_CIPHER_BLOWFISH
; break;
1458 case CIPHER_DES
: cipher_type
= SSH_CIPHER_DES
; break;
1459 case CIPHER_3DES
: cipher_type
= SSH_CIPHER_3DES
; break;
1461 c_write_str("AES not supported in SSH1, falling back to 3DES\r\n");
1462 cipher_type
= SSH_CIPHER_3DES
;
1465 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1466 c_write_str("Selected cipher not supported, falling back to 3DES\r\n");
1467 cipher_type
= SSH_CIPHER_3DES
;
1469 switch (cipher_type
) {
1470 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1471 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1472 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1475 send_packet(SSH1_CMSG_SESSION_KEY
,
1476 PKT_CHAR
, cipher_type
,
1477 PKT_DATA
, cookie
, 8,
1478 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1479 PKT_DATA
, rsabuf
, len
,
1483 logevent("Trying to enable encryption...");
1487 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1488 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1490 cipher
->sesskey(session_key
);
1494 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1495 bombout(("Encryption not successfully enabled"));
1499 logevent("Successfully started encryption");
1505 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1506 c_write_str("login as: ");
1509 crWaitUntil(!ispkt
);
1510 while (inlen
--) switch (c
= *in
++) {
1517 c_write_str("\b \b");
1523 c_write_str("\b \b");
1532 if (((c
>= ' ' && c
<= '~') ||
1533 ((unsigned char)c
>= 160)) && pos
< 40) {
1534 username
[pos
++] = c
;
1540 c_write_str("\r\n");
1541 username
[strcspn(username
, "\n\r")] = '\0';
1543 strncpy(username
, cfg
.username
, 99);
1544 username
[99] = '\0';
1547 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1549 char userlog
[22+sizeof(username
)];
1550 sprintf(userlog
, "Sent username \"%s\"", username
);
1552 if (flags
& FLAG_INTERACTIVE
&&
1553 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
1554 strcat(userlog
, "\r\n");
1555 c_write_str(userlog
);
1562 tried_publickey
= 0;
1564 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1565 static char password
[100];
1566 static char prompt
[200];
1569 static int pwpkt_type
;
1571 * Show password prompt, having first obtained it via a TIS
1572 * or CryptoCard exchange if we're doing TIS or CryptoCard
1575 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1576 if (agent_exists()) {
1578 * Attempt RSA authentication using Pageant.
1580 static unsigned char request
[5], *response
, *p
;
1581 static int responselen
;
1582 static int i
, nkeys
;
1583 static int authed
= FALSE
;
1586 logevent("Pageant is running. Requesting keys.");
1588 /* Request the keys held by the agent. */
1589 PUT_32BIT(request
, 1);
1590 request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
1591 agent_query(request
, 5, &r
, &responselen
);
1592 response
= (unsigned char *)r
;
1595 nkeys
= GET_32BIT(p
); p
+= 4;
1596 { char buf
[64]; sprintf(buf
, "Pageant has %d SSH1 keys", nkeys
);
1598 for (i
= 0; i
< nkeys
; i
++) {
1599 static struct RSAKey key
;
1600 static Bignum challenge
;
1601 static char *commentp
;
1602 static int commentlen
;
1604 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1607 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1608 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1609 commentlen
= GET_32BIT(p
); p
+= 4;
1610 commentp
= p
; p
+= commentlen
;
1611 send_packet(SSH1_CMSG_AUTH_RSA
,
1612 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1614 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1615 logevent("Key refused");
1618 logevent("Received RSA challenge");
1619 ssh1_read_bignum(pktin
.body
, &challenge
);
1621 char *agentreq
, *q
, *ret
;
1623 len
= 1 + 4; /* message type, bit count */
1624 len
+= ssh1_bignum_length(key
.exponent
);
1625 len
+= ssh1_bignum_length(key
.modulus
);
1626 len
+= ssh1_bignum_length(challenge
);
1627 len
+= 16; /* session id */
1628 len
+= 4; /* response format */
1629 agentreq
= smalloc(4 + len
);
1630 PUT_32BIT(agentreq
, len
);
1632 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
1633 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1635 q
+= ssh1_write_bignum(q
, key
.exponent
);
1636 q
+= ssh1_write_bignum(q
, key
.modulus
);
1637 q
+= ssh1_write_bignum(q
, challenge
);
1638 memcpy(q
, session_id
, 16); q
+= 16;
1639 PUT_32BIT(q
, 1); /* response format */
1640 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1643 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
1644 logevent("Sending Pageant's response");
1645 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1646 PKT_DATA
, ret
+5, 16, PKT_END
);
1649 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1650 logevent("Pageant's response accepted");
1651 if (flags
& FLAG_VERBOSE
) {
1652 c_write_str("Authenticated using RSA key \"");
1653 c_write(commentp
, commentlen
);
1654 c_write_str("\" from agent\r\n");
1658 logevent("Pageant's response not accepted");
1660 logevent("Pageant failed to answer challenge");
1664 logevent("No reply received from Pageant");
1667 freebn(key
.exponent
);
1668 freebn(key
.modulus
);
1677 if (*cfg
.keyfile
&& !tried_publickey
)
1678 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1680 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1682 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1683 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1684 logevent("Requested TIS authentication");
1685 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1687 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1688 logevent("TIS authentication declined");
1689 if (flags
& FLAG_INTERACTIVE
)
1690 c_write_str("TIS authentication refused.\r\n");
1692 int challengelen
= ((pktin
.body
[0] << 24) |
1693 (pktin
.body
[1] << 16) |
1694 (pktin
.body
[2] << 8) |
1696 logevent("Received TIS challenge");
1697 if (challengelen
> sizeof(prompt
)-1)
1698 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1699 memcpy(prompt
, pktin
.body
+4, challengelen
);
1700 prompt
[challengelen
] = '\0';
1703 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1705 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1706 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1707 logevent("Requested CryptoCard authentication");
1708 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1710 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1711 logevent("CryptoCard authentication declined");
1712 c_write_str("CryptoCard authentication refused.\r\n");
1714 int challengelen
= ((pktin
.body
[0] << 24) |
1715 (pktin
.body
[1] << 16) |
1716 (pktin
.body
[2] << 8) |
1718 logevent("Received CryptoCard challenge");
1719 if (challengelen
> sizeof(prompt
)-1)
1720 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1721 memcpy(prompt
, pktin
.body
+4, challengelen
);
1722 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1723 sizeof(prompt
)-challengelen
);
1724 prompt
[sizeof(prompt
)-1] = '\0';
1727 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1728 sprintf(prompt
, "%.90s@%.90s's password: ",
1729 username
, savedhost
);
1731 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1732 char *comment
= NULL
;
1733 if (flags
& FLAG_VERBOSE
)
1734 c_write_str("Trying public key authentication.\r\n");
1735 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1736 if (flags
& FLAG_VERBOSE
)
1737 c_write_str("No passphrase required.\r\n");
1740 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1744 if (ssh_get_password
) {
1745 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1747 * get_password failed to get a password (for
1748 * example because one was supplied on the command
1749 * line which has already failed to work).
1752 logevent("No more passwords to try");
1753 ssh_state
= SSH_STATE_CLOSED
;
1757 c_write_str(prompt
);
1761 crWaitUntil(!ispkt
);
1762 while (inlen
--) switch (c
= *in
++) {
1779 if (((c
>= ' ' && c
<= '~') ||
1780 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1781 password
[pos
++] = c
;
1785 c_write_str("\r\n");
1789 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1791 * Try public key authentication with the specified
1794 static struct RSAKey pubkey
;
1795 static Bignum challenge
, response
;
1797 static unsigned char buffer
[32];
1799 tried_publickey
= 1;
1800 i
= loadrsakey(cfg
.keyfile
, &pubkey
, password
);
1802 c_write_str("Couldn't load public key from ");
1803 c_write_str(cfg
.keyfile
);
1804 c_write_str(".\r\n");
1805 continue; /* go and try password */
1808 c_write_str("Wrong passphrase.\r\n");
1809 tried_publickey
= 0;
1810 continue; /* try again */
1814 * Send a public key attempt.
1816 send_packet(SSH1_CMSG_AUTH_RSA
,
1817 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1820 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1821 c_write_str("Server refused our public key.\r\n");
1822 continue; /* go and try password */
1824 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1825 bombout(("Bizarre response to offer of public key"));
1828 ssh1_read_bignum(pktin
.body
, &challenge
);
1829 response
= rsadecrypt(challenge
, &pubkey
);
1830 freebn(pubkey
.private_exponent
); /* burn the evidence */
1832 for (i
= 0; i
< 32; i
++) {
1833 buffer
[i
] = bignum_byte(response
, 31-i
);
1837 MD5Update(&md5c
, buffer
, 32);
1838 MD5Update(&md5c
, session_id
, 16);
1839 MD5Final(buffer
, &md5c
);
1841 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1842 PKT_DATA
, buffer
, 16, PKT_END
);
1845 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1846 if (flags
& FLAG_VERBOSE
)
1847 c_write_str("Failed to authenticate with our public key.\r\n");
1848 continue; /* go and try password */
1849 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1850 bombout(("Bizarre response to RSA authentication response"));
1854 break; /* we're through! */
1856 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1858 * Defence against traffic analysis: we send a
1859 * whole bunch of packets containing strings of
1860 * different lengths. One of these strings is the
1861 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
1862 * The others are all random data in
1863 * SSH1_MSG_IGNORE packets. This way a passive
1864 * listener can't tell which is the password, and
1865 * hence can't deduce the password length.
1867 * Anybody with a password length greater than 16
1868 * bytes is going to have enough entropy in their
1869 * password that a listener won't find it _that_
1870 * much help to know how long it is. So what we'll
1873 * - if password length < 16, we send 15 packets
1874 * containing string lengths 1 through 15
1876 * - otherwise, we let N be the nearest multiple
1877 * of 8 below the password length, and send 8
1878 * packets containing string lengths N through
1879 * N+7. This won't obscure the order of
1880 * magnitude of the password length, but it will
1881 * introduce a bit of extra uncertainty.
1883 * A few servers (the old 1.2.18 through 1.2.22)
1884 * can't deal with SSH1_MSG_IGNORE. For these
1885 * servers, we need an alternative defence. We make
1886 * use of the fact that the password is interpreted
1887 * as a C string: so we can append a NUL, then some
1890 if (ssh_remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
) {
1895 len
= strlen(password
);
1896 if (len
< sizeof(string
)) {
1898 strcpy(string
, password
);
1899 len
++; /* cover the zero byte */
1900 while (len
< sizeof(string
)) {
1901 string
[len
++] = (char)random_byte();
1906 send_packet(pwpkt_type
, PKT_INT
, len
,
1907 PKT_DATA
, s
, len
, PKT_END
);
1909 int bottom
, top
, pwlen
, i
;
1912 pwlen
= strlen(password
);
1917 bottom
= pwlen
&~ 7;
1921 assert(pwlen
>= bottom
&& pwlen
<= top
);
1923 randomstr
= smalloc(top
+1);
1925 for (i
= bottom
; i
<= top
; i
++) {
1927 defer_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1929 for (j
= 0; j
< i
; j
++) {
1931 randomstr
[j
] = random_byte();
1932 } while (randomstr
[j
] == '\0');
1934 randomstr
[i
] = '\0';
1935 defer_packet(SSH1_MSG_IGNORE
,
1936 PKT_STR
, randomstr
, PKT_END
);
1939 ssh_pkt_defersend();
1942 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1945 logevent("Sent password");
1946 memset(password
, 0, strlen(password
));
1948 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1949 if (flags
& FLAG_VERBOSE
)
1950 c_write_str("Access denied\r\n");
1951 logevent("Authentication refused");
1952 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1953 logevent("Received disconnect request");
1954 ssh_state
= SSH_STATE_CLOSED
;
1956 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1957 bombout(("Strange packet received, type %d", pktin
.type
));
1962 logevent("Authentication successful");
1967 void sshfwd_close(struct ssh_channel
*c
) {
1969 if (ssh_version
== 1) {
1970 send_packet(SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
, PKT_END
);
1972 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
1973 ssh2_pkt_adduint32(c
->remoteid
);
1977 if (c
->type
== CHAN_X11
) {
1979 logevent("X11 connection terminated");
1984 void sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
) {
1985 if (ssh_version
== 1) {
1986 send_packet(SSH1_MSG_CHANNEL_DATA
,
1987 PKT_INT
, c
->remoteid
,
1992 ssh2_add_channel_data(c
, buf
, len
);
1997 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
2002 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
2005 if (ssh_state
== SSH_STATE_CLOSED
)
2008 if (cfg
.agentfwd
&& agent_exists()) {
2009 logevent("Requesting agent forwarding");
2010 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
2011 do { crReturnV
; } while (!ispkt
);
2012 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
2013 bombout(("Protocol confusion"));
2015 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2016 logevent("Agent forwarding refused");
2018 logevent("Agent forwarding enabled");
2019 ssh_agentfwd_enabled
= TRUE
;
2023 if (cfg
.x11_forward
) {
2024 char proto
[20], data
[64];
2025 logevent("Requesting X11 forwarding");
2026 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
2027 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING
,
2028 PKT_STR
, proto
, PKT_STR
, data
,
2031 do { crReturnV
; } while (!ispkt
);
2032 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
2033 bombout(("Protocol confusion"));
2035 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2036 logevent("X11 forwarding refused");
2038 logevent("X11 forwarding enabled");
2039 ssh_X11_fwd_enabled
= TRUE
;
2044 send_packet(SSH1_CMSG_REQUEST_PTY
,
2045 PKT_STR
, cfg
.termtype
,
2046 PKT_INT
, rows
, PKT_INT
, cols
,
2047 PKT_INT
, 0, PKT_INT
, 0,
2050 ssh_state
= SSH_STATE_INTERMED
;
2051 do { crReturnV
; } while (!ispkt
);
2052 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
2053 bombout(("Protocol confusion"));
2055 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2056 c_write_str("Server refused to allocate pty\r\n");
2057 ssh_editing
= ssh_echoing
= 1;
2059 logevent("Allocated pty");
2061 ssh_editing
= ssh_echoing
= 1;
2064 if (cfg
.compression
) {
2065 send_packet(SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
2066 do { crReturnV
; } while (!ispkt
);
2067 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
2068 bombout(("Protocol confusion"));
2070 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2071 c_write_str("Server refused to compress\r\n");
2073 logevent("Started compression");
2074 ssh1_compressing
= TRUE
;
2075 zlib_compress_init();
2076 zlib_decompress_init();
2079 if (*cfg
.remote_cmd
)
2080 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
2082 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
2083 logevent("Started session");
2085 ssh_state
= SSH_STATE_SESSION
;
2089 ssh_special(TS_EOF
);
2091 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
2093 ssh_channels
= newtree234(ssh_channelcmp
);
2097 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
2098 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
2099 long len
= GET_32BIT(pktin
.body
);
2100 from_backend(pktin
.type
== SSH1_SMSG_STDERR_DATA
,
2102 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
2103 ssh_state
= SSH_STATE_CLOSED
;
2104 logevent("Received disconnect request");
2106 } else if (pktin
.type
== SSH1_SMSG_X11_OPEN
) {
2107 /* Remote side is trying to open a channel to talk to our
2108 * X-Server. Give them back a local channel number. */
2110 struct ssh_channel
*c
, *d
;
2113 logevent("Received X11 connect request");
2114 /* Refuse if X11 forwarding is disabled. */
2115 if (!ssh_X11_fwd_enabled
) {
2116 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2117 PKT_INT
, GET_32BIT(pktin
.body
),
2119 logevent("Rejected X11 connect request");
2121 c
= smalloc(sizeof(struct ssh_channel
));
2123 if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
2124 logevent("opening X11 forward connection failed");
2126 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2127 PKT_INT
, GET_32BIT(pktin
.body
),
2130 logevent("opening X11 forward connection succeeded");
2131 for (i
=1, d
= first234(ssh_channels
, &e
); d
; d
= next234(&e
)) {
2133 break; /* found a free number */
2136 c
->remoteid
= GET_32BIT(pktin
.body
);
2139 c
->type
= CHAN_X11
; /* identify channel type */
2140 add234(ssh_channels
, c
);
2141 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2142 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2144 logevent("Opened X11 forward channel");
2147 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
2148 /* Remote side is trying to open a channel to talk to our
2149 * agent. Give them back a local channel number. */
2151 struct ssh_channel
*c
;
2154 /* Refuse if agent forwarding is disabled. */
2155 if (!ssh_agentfwd_enabled
) {
2156 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE
,
2157 PKT_INT
, GET_32BIT(pktin
.body
),
2161 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
2163 break; /* found a free number */
2166 c
= smalloc(sizeof(struct ssh_channel
));
2167 c
->remoteid
= GET_32BIT(pktin
.body
);
2170 c
->type
= CHAN_AGENT
; /* identify channel type */
2171 c
->u
.a
.lensofar
= 0;
2172 add234(ssh_channels
, c
);
2173 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
2174 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
2177 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
2178 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
2179 /* Remote side closes a channel. */
2180 unsigned i
= GET_32BIT(pktin
.body
);
2181 struct ssh_channel
*c
;
2182 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2185 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
2186 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
2187 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
2188 logevent("X11 connection closed");
2189 assert(c
->u
.x11
.s
!= NULL
);
2190 x11_close(c
->u
.x11
.s
);
2193 c
->closes
|= closetype
;
2194 if (c
->closes
== 3) {
2195 del234(ssh_channels
, c
);
2199 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
2200 /* Data sent down one of our channels. */
2201 int i
= GET_32BIT(pktin
.body
);
2202 int len
= GET_32BIT(pktin
.body
+4);
2203 unsigned char *p
= pktin
.body
+8;
2204 struct ssh_channel
*c
;
2205 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
2209 x11_send(c
->u
.x11
.s
, p
, len
);
2212 /* Data for an agent message. Buffer it. */
2214 if (c
->u
.a
.lensofar
< 4) {
2215 int l
= min(4 - c
->u
.a
.lensofar
, len
);
2216 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
2217 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2219 if (c
->u
.a
.lensofar
== 4) {
2220 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
2221 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
2222 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
2224 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
2225 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
2226 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
2227 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
2229 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
2230 void *reply
, *sentreply
;
2232 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
2237 /* Fake SSH_AGENT_FAILURE. */
2238 sentreply
= "\0\0\0\1\5";
2241 send_packet(SSH1_MSG_CHANNEL_DATA
,
2242 PKT_INT
, c
->remoteid
,
2244 PKT_DATA
, sentreply
, replylen
,
2248 sfree(c
->u
.a
.message
);
2249 c
->u
.a
.lensofar
= 0;
2255 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
2256 /* may be from EXEC_SHELL on some servers */
2257 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
2258 /* may be from EXEC_SHELL on some servers
2259 * if no pty is available or in other odd cases. Ignore */
2260 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
2261 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
2263 bombout(("Strange packet received: type %d", pktin
.type
));
2268 int len
= min(inlen
, 512);
2269 send_packet(SSH1_CMSG_STDIN_DATA
,
2270 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
2281 * Utility routine for decoding comma-separated strings in KEXINIT.
2283 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
2284 int needlen
= strlen(needle
);
2287 * Is it at the start of the string?
2289 if (haylen
>= needlen
&& /* haystack is long enough */
2290 !memcmp(needle
, haystack
, needlen
) && /* initial match */
2291 (haylen
== needlen
|| haystack
[needlen
] == ',')
2292 /* either , or EOS follows */
2296 * If not, search for the next comma and resume after that.
2297 * If no comma found, terminate.
2299 while (haylen
> 0 && *haystack
!= ',')
2300 haylen
--, haystack
++;
2303 haylen
--, haystack
++; /* skip over comma itself */
2308 * SSH2 key creation method.
2310 static void ssh2_mkkey(Bignum K
, char *H
, char *sessid
, char chr
, char *keyspace
) {
2312 /* First 20 bytes. */
2315 SHA_Bytes(&s
, H
, 20);
2316 SHA_Bytes(&s
, &chr
, 1);
2317 SHA_Bytes(&s
, sessid
, 20);
2318 SHA_Final(&s
, keyspace
);
2319 /* Next 20 bytes. */
2322 SHA_Bytes(&s
, H
, 20);
2323 SHA_Bytes(&s
, keyspace
, 20);
2324 SHA_Final(&s
, keyspace
+20);
2328 * Handle the SSH2 transport layer.
2330 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
2332 static int i
, j
, len
, nbits
;
2334 static Bignum p
, g
, e
, f
, K
;
2335 static int kex_init_value
, kex_reply_value
;
2336 static const struct ssh_mac
**maclist
;
2338 static const struct ssh2_cipher
*cscipher_tobe
= NULL
;
2339 static const struct ssh2_cipher
*sccipher_tobe
= NULL
;
2340 static const struct ssh_mac
*csmac_tobe
= NULL
;
2341 static const struct ssh_mac
*scmac_tobe
= NULL
;
2342 static const struct ssh_compress
*cscomp_tobe
= NULL
;
2343 static const struct ssh_compress
*sccomp_tobe
= NULL
;
2344 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
2345 static int hostkeylen
, siglen
;
2346 static void *hkey
; /* actual host key */
2347 static unsigned char exchange_hash
[20];
2348 static unsigned char keyspace
[40];
2349 static const struct ssh2_ciphers
*preferred_cipher
;
2350 static const struct ssh_compress
*preferred_comp
;
2351 static int first_kex
;
2358 * Set up the preferred cipher and compression.
2360 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
2361 preferred_cipher
= &ssh2_blowfish
;
2362 } else if (cfg
.cipher
== CIPHER_DES
) {
2363 logevent("Single DES not supported in SSH2; using 3DES");
2364 preferred_cipher
= &ssh2_3des
;
2365 } else if (cfg
.cipher
== CIPHER_3DES
) {
2366 preferred_cipher
= &ssh2_3des
;
2367 } else if (cfg
.cipher
== CIPHER_AES
) {
2368 preferred_cipher
= &ssh2_aes
;
2370 /* Shouldn't happen, but we do want to initialise to _something_. */
2371 preferred_cipher
= &ssh2_3des
;
2373 if (cfg
.compression
)
2374 preferred_comp
= &ssh_zlib
;
2376 preferred_comp
= &ssh_comp_none
;
2379 * Be prepared to work around the buggy MAC problem.
2381 if (cfg
.buggymac
|| (ssh_remote_bugs
& BUG_SSH2_HMAC
))
2382 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
2384 maclist
= macs
, nmacs
= lenof(macs
);
2388 * Construct and send our key exchange packet.
2390 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
2391 for (i
= 0; i
< 16; i
++)
2392 ssh2_pkt_addbyte((unsigned char)random_byte());
2393 /* List key exchange algorithms. */
2394 ssh2_pkt_addstring_start();
2395 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2396 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
2397 if (i
< lenof(kex_algs
)-1)
2398 ssh2_pkt_addstring_str(",");
2400 /* List server host key algorithms. */
2401 ssh2_pkt_addstring_start();
2402 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2403 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
2404 if (i
< lenof(hostkey_algs
)-1)
2405 ssh2_pkt_addstring_str(",");
2407 /* List client->server encryption algorithms. */
2408 ssh2_pkt_addstring_start();
2409 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2410 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2411 for (j
= 0; j
< c
->nciphers
; j
++) {
2412 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2413 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2414 ssh2_pkt_addstring_str(",");
2417 /* List server->client encryption algorithms. */
2418 ssh2_pkt_addstring_start();
2419 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2420 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2421 for (j
= 0; j
< c
->nciphers
; j
++) {
2422 ssh2_pkt_addstring_str(c
->list
[j
]->name
);
2423 if (i
< lenof(ciphers
) || j
< c
->nciphers
-1)
2424 ssh2_pkt_addstring_str(",");
2427 /* List client->server MAC algorithms. */
2428 ssh2_pkt_addstring_start();
2429 for (i
= 0; i
< nmacs
; i
++) {
2430 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2432 ssh2_pkt_addstring_str(",");
2434 /* List server->client MAC algorithms. */
2435 ssh2_pkt_addstring_start();
2436 for (i
= 0; i
< nmacs
; i
++) {
2437 ssh2_pkt_addstring_str(maclist
[i
]->name
);
2439 ssh2_pkt_addstring_str(",");
2441 /* List client->server compression algorithms. */
2442 ssh2_pkt_addstring_start();
2443 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2444 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2445 ssh2_pkt_addstring_str(c
->name
);
2446 if (i
< lenof(compressions
))
2447 ssh2_pkt_addstring_str(",");
2449 /* List server->client compression algorithms. */
2450 ssh2_pkt_addstring_start();
2451 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2452 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2453 ssh2_pkt_addstring_str(c
->name
);
2454 if (i
< lenof(compressions
))
2455 ssh2_pkt_addstring_str(",");
2457 /* List client->server languages. Empty list. */
2458 ssh2_pkt_addstring_start();
2459 /* List server->client languages. Empty list. */
2460 ssh2_pkt_addstring_start();
2461 /* First KEX packet does _not_ follow, because we're not that brave. */
2462 ssh2_pkt_addbool(FALSE
);
2464 ssh2_pkt_adduint32(0);
2466 exhash
= exhashbase
;
2467 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
2471 if (!ispkt
) crWaitUntil(ispkt
);
2472 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
2475 * Now examine the other side's KEXINIT to see what we're up
2478 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
2479 bombout(("expected key exchange packet from server"));
2482 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
2483 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
2484 pktin
.savedpos
+= 16; /* skip garbage cookie */
2485 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
2486 for (i
= 0; i
< lenof(kex_algs
); i
++) {
2487 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
2492 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
2493 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
2494 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
2495 hostkey
= hostkey_algs
[i
];
2499 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
2500 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2501 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2502 for (j
= 0; j
< c
->nciphers
; j
++) {
2503 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2504 cscipher_tobe
= c
->list
[j
];
2511 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
2512 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2513 const struct ssh2_ciphers
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2514 for (j
= 0; j
< c
->nciphers
; j
++) {
2515 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
2516 sccipher_tobe
= c
->list
[j
];
2523 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2524 for (i
= 0; i
< nmacs
; i
++) {
2525 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2526 csmac_tobe
= maclist
[i
];
2530 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2531 for (i
= 0; i
< nmacs
; i
++) {
2532 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2533 scmac_tobe
= maclist
[i
];
2537 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2538 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2539 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2540 if (in_commasep_string(c
->name
, str
, len
)) {
2545 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2546 for (i
= 0; i
< lenof(compressions
)+1; i
++) {
2547 const struct ssh_compress
*c
= i
==0 ? preferred_comp
: compressions
[i
-1];
2548 if (in_commasep_string(c
->name
, str
, len
)) {
2555 * If we're doing Diffie-Hellman group exchange, start by
2556 * requesting a group.
2558 if (kex
== &ssh_diffiehellman_gex
) {
2561 logevent("Doing Diffie-Hellman group exchange");
2563 * Work out number of bits. We start with the maximum key
2564 * length of either cipher...
2566 csbits
= cscipher_tobe
->keylen
;
2567 scbits
= sccipher_tobe
->keylen
;
2568 nbits
= (csbits
> scbits ? csbits
: scbits
);
2569 /* The keys only have 160-bit entropy, since they're based on
2570 * a SHA-1 hash. So cap the key size at 160 bits. */
2571 if (nbits
> 160) nbits
= 160;
2573 * ... and then work out how big a DH group we will need to
2574 * allow that much data.
2576 nbits
= 512 << ((nbits
-1) / 64);
2577 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST
);
2578 ssh2_pkt_adduint32(nbits
);
2582 if (pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
2583 bombout(("expected key exchange group packet from server"));
2586 p
= ssh2_pkt_getmp();
2587 g
= ssh2_pkt_getmp();
2588 dh_setup_group(p
, g
);
2589 kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
2590 kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
2593 kex_init_value
= SSH2_MSG_KEXDH_INIT
;
2594 kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
2597 logevent("Doing Diffie-Hellman key exchange");
2599 * Now generate and send e for Diffie-Hellman.
2602 ssh2_pkt_init(kex_init_value
);
2607 if (pktin
.type
!= kex_reply_value
) {
2608 bombout(("expected key exchange reply packet from server"));
2611 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2612 f
= ssh2_pkt_getmp();
2613 ssh2_pkt_getstring(&sigdata
, &siglen
);
2617 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2618 if (kex
== &ssh_diffiehellman_gex
) {
2619 sha_uint32(&exhash
, nbits
);
2620 sha_mpint(&exhash
, p
);
2621 sha_mpint(&exhash
, g
);
2623 sha_mpint(&exhash
, e
);
2624 sha_mpint(&exhash
, f
);
2625 sha_mpint(&exhash
, K
);
2626 SHA_Final(&exhash
, exchange_hash
);
2631 debug(("Exchange hash is:\r\n"));
2632 for (i
= 0; i
< 20; i
++)
2633 debug((" %02x", exchange_hash
[i
]));
2637 hkey
= hostkey
->newkey(hostkeydata
, hostkeylen
);
2638 if (!hostkey
->verifysig(hkey
, sigdata
, siglen
, exchange_hash
, 20)) {
2639 bombout(("Server failed host key check"));
2644 * Expect SSH2_MSG_NEWKEYS from server.
2647 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2648 bombout(("expected new-keys packet from server"));
2653 * Authenticate remote host: verify host key. (We've already
2654 * checked the signature of the exchange hash.)
2656 keystr
= hostkey
->fmtkey(hkey
);
2657 fingerprint
= hostkey
->fingerprint(hkey
);
2658 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2659 keystr
, fingerprint
);
2660 if (first_kex
) { /* don't bother logging this in rekeys */
2661 logevent("Host key fingerprint is:");
2662 logevent(fingerprint
);
2666 hostkey
->freekey(hkey
);
2669 * Send SSH2_MSG_NEWKEYS.
2671 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2675 * Create and initialise session keys.
2677 cscipher
= cscipher_tobe
;
2678 sccipher
= sccipher_tobe
;
2681 cscomp
= cscomp_tobe
;
2682 sccomp
= sccomp_tobe
;
2683 cscomp
->compress_init();
2684 sccomp
->decompress_init();
2686 * Set IVs after keys. Here we use the exchange hash from the
2687 * _first_ key exchange.
2690 memcpy(ssh2_session_id
, exchange_hash
, sizeof(exchange_hash
));
2691 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'C', keyspace
);
2692 cscipher
->setcskey(keyspace
);
2693 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'D', keyspace
);
2694 sccipher
->setsckey(keyspace
);
2695 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'A', keyspace
);
2696 cscipher
->setcsiv(keyspace
);
2697 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'B', keyspace
);
2698 sccipher
->setsciv(keyspace
);
2699 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'E', keyspace
);
2700 csmac
->setcskey(keyspace
);
2701 ssh2_mkkey(K
, exchange_hash
, ssh2_session_id
, 'F', keyspace
);
2702 scmac
->setsckey(keyspace
);
2705 * If this is the first key exchange phase, we must pass the
2706 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
2707 * wants to see it but because it will need time to initialise
2708 * itself before it sees an actual packet. In subsequent key
2709 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
2710 * it would only confuse the layer above.
2718 * Now we're encrypting. Begin returning 1 to the protocol main
2719 * function so that other things can run on top of the
2720 * transport. If we ever see a KEXINIT, we must go back to the
2723 while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
)) {
2726 logevent("Server initiated key re-exchange");
2727 goto begin_key_exchange
;
2733 * Add data to an SSH2 channel output buffer.
2735 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
) {
2736 if (c
->v2
.outbufsize
<
2737 c
->v2
.outbuflen
+ len
) {
2739 c
->v2
.outbuflen
+ len
+ 1024;
2740 c
->v2
.outbuffer
= srealloc(c
->v2
.outbuffer
,
2743 memcpy(c
->v2
.outbuffer
+ c
->v2
.outbuflen
,
2745 c
->v2
.outbuflen
+= len
;
2749 * Attempt to send data on an SSH2 channel.
2751 static void ssh2_try_send(struct ssh_channel
*c
) {
2752 while (c
->v2
.remwindow
> 0 &&
2753 c
->v2
.outbuflen
> 0) {
2754 unsigned len
= c
->v2
.remwindow
;
2755 if (len
> c
->v2
.outbuflen
)
2756 len
= c
->v2
.outbuflen
;
2757 if (len
> c
->v2
.remmaxpkt
)
2758 len
= c
->v2
.remmaxpkt
;
2759 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2760 ssh2_pkt_adduint32(c
->remoteid
);
2761 ssh2_pkt_addstring_start();
2762 ssh2_pkt_addstring_data(c
->v2
.outbuffer
, len
);
2764 c
->v2
.outbuflen
-= len
;
2765 memmove(c
->v2
.outbuffer
, c
->v2
.outbuffer
+len
,
2767 c
->v2
.remwindow
-= len
;
2772 * Handle the SSH2 userauth and connection layers.
2774 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2776 static unsigned long remote_winsize
;
2777 static unsigned long remote_maxpkt
;
2779 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
, AUTH_PASSWORD
2783 AUTH_TYPE_PUBLICKEY
,
2784 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
2785 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
2788 static int gotit
, need_pw
, can_pubkey
, can_passwd
;
2789 static int tried_pubkey_config
, tried_agent
;
2790 static int we_are_in
;
2791 static char username
[100];
2792 static char pwprompt
[200];
2793 static char password
[100];
2798 * Request userauth protocol, and await a response to it.
2800 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2801 ssh2_pkt_addstring("ssh-userauth");
2803 crWaitUntilV(ispkt
);
2804 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2805 bombout(("Server refused user authentication protocol"));
2810 * We repeat this whole loop, including the username prompt,
2811 * until we manage a successful authentication. If the user
2812 * types the wrong _password_, they are sent back to the
2813 * beginning to try another username. (If they specify a
2814 * username in the config, they are never asked, even if they
2815 * do give a wrong password.)
2817 * I think this best serves the needs of
2819 * - the people who have no configuration, no keys, and just
2820 * want to try repeated (username,password) pairs until they
2821 * type both correctly
2823 * - people who have keys and configuration but occasionally
2824 * need to fall back to passwords
2826 * - people with a key held in Pageant, who might not have
2827 * logged in to a particular machine before; so they want to
2828 * type a username, and then _either_ their key will be
2829 * accepted, _or_ they will type a password. If they mistype
2830 * the username they will want to be able to get back and
2841 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2842 c_write_str("login as: ");
2845 crWaitUntilV(!ispkt
);
2846 while (inlen
--) switch (c
= *in
++) {
2853 c_write_str("\b \b");
2859 c_write_str("\b \b");
2868 if (((c
>= ' ' && c
<= '~') ||
2869 ((unsigned char)c
>= 160)) && pos
< 40) {
2870 username
[pos
++] = c
;
2876 c_write_str("\r\n");
2877 username
[strcspn(username
, "\n\r")] = '\0';
2880 strncpy(username
, cfg
.username
, 99);
2881 username
[99] = '\0';
2882 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2883 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2889 * Send an authentication request using method "none": (a)
2890 * just in case it succeeds, and (b) so that we know what
2891 * authentication methods we can usefully try next.
2893 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2894 ssh2_pkt_addstring(username
);
2895 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2896 ssh2_pkt_addstring("none"); /* method */
2898 type
= AUTH_TYPE_NONE
;
2902 tried_pubkey_config
= FALSE
;
2903 tried_agent
= FALSE
;
2907 * Wait for the result of the last authentication request.
2910 crWaitUntilV(ispkt
);
2911 while (pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
2912 /* FIXME: should support this */
2913 crWaitUntilV(ispkt
);
2915 if (pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
2916 logevent("Access granted");
2921 if (pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
2922 bombout(("Strange packet received during authentication: type %d",
2929 * OK, we're now sitting on a USERAUTH_FAILURE message, so
2930 * we can look at the string in it and know what we can
2931 * helpfully try next.
2936 ssh2_pkt_getstring(&methods
, &methlen
);
2937 if (!ssh2_pkt_getbool()) {
2939 * We have received an unequivocal Access
2940 * Denied. This can translate to a variety of
2943 * - if we'd just tried "none" authentication,
2944 * it's not worth printing anything at all
2946 * - if we'd just tried a public key _offer_,
2947 * the message should be "Server refused our
2948 * key" (or no message at all if the key
2949 * came from Pageant)
2951 * - if we'd just tried anything else, the
2952 * message really should be "Access denied".
2954 * Additionally, if we'd just tried password
2955 * authentication, we should break out of this
2956 * whole loop so as to go back to the username
2959 if (type
== AUTH_TYPE_NONE
) {
2961 } else if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
2962 type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
2963 if (type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
2964 c_write_str("Server refused our key\r\n");
2965 logevent("Server refused public key");
2967 c_write_str("Access denied\r\n");
2968 logevent("Access denied");
2969 if (type
== AUTH_TYPE_PASSWORD
) {
2975 c_write_str("Further authentication required\r\n");
2976 logevent("Further authentication required");
2979 can_pubkey
= in_commasep_string("publickey", methods
, methlen
);
2980 can_passwd
= in_commasep_string("password", methods
, methlen
);
2985 if (!method
&& can_pubkey
&& agent_exists
&& !tried_agent
) {
2987 * Attempt public-key authentication using Pageant.
2989 static unsigned char request
[5], *response
, *p
;
2990 static int responselen
;
2991 static int i
, nkeys
;
2992 static int authed
= FALSE
;
2997 logevent("Pageant is running. Requesting keys.");
2999 /* Request the keys held by the agent. */
3000 PUT_32BIT(request
, 1);
3001 request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
3002 agent_query(request
, 5, &r
, &responselen
);
3003 response
= (unsigned char *)r
;
3006 nkeys
= GET_32BIT(p
); p
+= 4;
3007 { char buf
[64]; sprintf(buf
, "Pageant has %d SSH2 keys", nkeys
);
3009 for (i
= 0; i
< nkeys
; i
++) {
3010 static char *pkblob
, *alg
, *commentp
;
3011 static int pklen
, alglen
, commentlen
;
3012 static int siglen
, retlen
, len
;
3013 static char *q
, *agentreq
, *ret
;
3015 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
3017 pklen
= GET_32BIT(p
); p
+= 4;
3018 pkblob
= p
; p
+= pklen
;
3019 alglen
= GET_32BIT(pkblob
);
3021 commentlen
= GET_32BIT(p
); p
+= 4;
3022 commentp
= p
; p
+= commentlen
;
3023 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3024 ssh2_pkt_addstring(username
);
3025 ssh2_pkt_addstring("ssh-connection");/* service requested */
3026 ssh2_pkt_addstring("publickey");/* method */
3027 ssh2_pkt_addbool(FALSE
); /* no signature included */
3028 ssh2_pkt_addstring_start();
3029 ssh2_pkt_addstring_data(alg
, alglen
);
3030 ssh2_pkt_addstring_start();
3031 ssh2_pkt_addstring_data(pkblob
, pklen
);
3034 crWaitUntilV(ispkt
);
3035 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
3036 logevent("Key refused");
3040 c_write_str("Authenticating with public key \"");
3041 c_write(commentp
, commentlen
);
3042 c_write_str("\" from agent\r\n");
3045 * Server is willing to accept the key.
3046 * Construct a SIGN_REQUEST.
3048 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3049 ssh2_pkt_addstring(username
);
3050 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3051 ssh2_pkt_addstring("publickey"); /* method */
3052 ssh2_pkt_addbool(TRUE
);
3053 ssh2_pkt_addstring_start();
3054 ssh2_pkt_addstring_data(alg
, alglen
);
3055 ssh2_pkt_addstring_start();
3056 ssh2_pkt_addstring_data(pkblob
, pklen
);
3058 siglen
= pktout
.length
- 5 + 4 + 20;
3059 len
= 1; /* message type */
3060 len
+= 4 + pklen
; /* key blob */
3061 len
+= 4 + siglen
; /* data to sign */
3062 len
+= 4; /* flags */
3063 agentreq
= smalloc(4 + len
);
3064 PUT_32BIT(agentreq
, len
);
3066 *q
++ = SSH2_AGENTC_SIGN_REQUEST
;
3067 PUT_32BIT(q
, pklen
); q
+= 4;
3068 memcpy(q
, pkblob
, pklen
); q
+= pklen
;
3069 PUT_32BIT(q
, siglen
); q
+= 4;
3070 /* Now the data to be signed... */
3071 PUT_32BIT(q
, 20); q
+= 4;
3072 memcpy(q
, ssh2_session_id
, 20); q
+= 20;
3073 memcpy(q
, pktout
.data
+5, pktout
.length
-5);
3074 q
+= pktout
.length
-5;
3075 /* And finally the (zero) flags word. */
3077 agent_query(agentreq
, len
+4, &ret
, &retlen
);
3080 if (ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
3081 logevent("Sending Pageant's response");
3082 ssh2_pkt_addstring_start();
3083 ssh2_pkt_addstring_data(ret
+9, GET_32BIT(ret
+5));
3088 logevent("Pageant failed to answer challenge");
3098 if (!method
&& can_pubkey
&& *cfg
.keyfile
&& !tried_pubkey_config
) {
3099 unsigned char *pub_blob
;
3100 char *algorithm
, *comment
;
3103 tried_pubkey_config
= TRUE
;
3106 * Try the public key supplied in the configuration.
3108 * First, offer the public blob to see if the server is
3109 * willing to accept it.
3111 pub_blob
= ssh2_userkey_loadpub(cfg
.keyfile
, &algorithm
,
3114 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3115 ssh2_pkt_addstring(username
);
3116 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3117 ssh2_pkt_addstring("publickey");/* method */
3118 ssh2_pkt_addbool(FALSE
); /* no signature included */
3119 ssh2_pkt_addstring(algorithm
);
3120 ssh2_pkt_addstring_start();
3121 ssh2_pkt_addstring_data(pub_blob
, pub_blob_len
);
3123 logevent("Offered public key"); /* FIXME */
3125 crWaitUntilV(ispkt
);
3126 if (pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
3128 type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
3129 continue; /* key refused; give up on it */
3132 logevent("Offer of public key accepted");
3134 * Actually attempt a serious authentication using
3137 if (ssh2_userkey_encrypted(cfg
.keyfile
, &comment
)) {
3138 sprintf(pwprompt
, "Passphrase for key \"%.100s\": ", comment
);
3143 c_write_str("Authenticating with public key \"");
3144 c_write_str(comment
);
3145 c_write_str("\"\r\n");
3146 method
= AUTH_PUBLICKEY_FILE
;
3150 if (!method
&& can_passwd
) {
3151 method
= AUTH_PASSWORD
;
3152 sprintf(pwprompt
, "%.90s@%.90s's password: ", username
, savedhost
);
3157 if (ssh_get_password
) {
3158 if (!ssh_get_password(pwprompt
, password
, sizeof(password
))) {
3160 * get_password failed to get a password (for
3161 * example because one was supplied on the command
3162 * line which has already failed to work).
3165 logevent("No more passwords to try");
3166 ssh_state
= SSH_STATE_CLOSED
;
3173 c_write_str(pwprompt
);
3178 crWaitUntilV(!ispkt
);
3179 while (inlen
--) switch (c
= *in
++) {
3196 if (((c
>= ' ' && c
<= '~') ||
3197 ((unsigned char)c
>= 160)) && pos
< 40)
3198 password
[pos
++] = c
;
3202 c_write_str("\r\n");
3206 if (method
== AUTH_PUBLICKEY_FILE
) {
3208 * We have our passphrase. Now try the actual authentication.
3210 struct ssh2_userkey
*key
;
3212 key
= ssh2_load_userkey(cfg
.keyfile
, password
);
3213 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
3214 if (key
== SSH2_WRONG_PASSPHRASE
) {
3215 c_write_str("Wrong passphrase\r\n");
3216 tried_pubkey_config
= FALSE
;
3218 c_write_str("Unable to load private key\r\n");
3219 tried_pubkey_config
= TRUE
;
3221 /* Send a spurious AUTH_NONE to return to the top. */
3222 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3223 ssh2_pkt_addstring(username
);
3224 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3225 ssh2_pkt_addstring("none"); /* method */
3227 type
= AUTH_TYPE_NONE
;
3229 unsigned char *blob
, *sigdata
;
3230 int blob_len
, sigdata_len
;
3233 * We have loaded the private key and the server
3234 * has announced that it's willing to accept it.
3235 * Hallelujah. Generate a signature and send it.
3237 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3238 ssh2_pkt_addstring(username
);
3239 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3240 ssh2_pkt_addstring("publickey"); /* method */
3241 ssh2_pkt_addbool(TRUE
);
3242 ssh2_pkt_addstring(key
->alg
->name
);
3243 blob
= key
->alg
->public_blob(key
->data
, &blob_len
);
3244 ssh2_pkt_addstring_start();
3245 ssh2_pkt_addstring_data(blob
, blob_len
);
3249 * The data to be signed is:
3253 * followed by everything so far placed in the
3256 sigdata_len
= pktout
.length
- 5 + 4 + 20;
3257 sigdata
= smalloc(sigdata_len
);
3258 PUT_32BIT(sigdata
, 20);
3259 memcpy(sigdata
+4, ssh2_session_id
, 20);
3260 memcpy(sigdata
+24, pktout
.data
+5, pktout
.length
-5);
3261 blob
= key
->alg
->sign(key
->data
, sigdata
, sigdata_len
, &blob_len
);
3262 ssh2_pkt_addstring_start();
3263 ssh2_pkt_addstring_data(blob
, blob_len
);
3268 type
= AUTH_TYPE_PUBLICKEY
;
3270 } else if (method
== AUTH_PASSWORD
) {
3272 * We send the password packet lumped tightly together with
3273 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
3274 * string long enough to make the total length of the two
3275 * packets constant. This should ensure that a passive
3276 * listener doing traffic analyis can't work out the length
3279 * For this to work, we need an assumption about the
3280 * maximum length of the password packet. I think 256 is
3281 * pretty conservative. Anyone using a password longer than
3282 * that probably doesn't have much to worry about from
3283 * people who find out how long their password is!
3285 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
3286 ssh2_pkt_addstring(username
);
3287 ssh2_pkt_addstring("ssh-connection"); /* service requested */
3288 ssh2_pkt_addstring("password");
3289 ssh2_pkt_addbool(FALSE
);
3290 ssh2_pkt_addstring(password
);
3293 * We'll include a string that's an exact multiple of the
3294 * cipher block size. If the cipher is NULL for some
3295 * reason, we don't do this trick at all because we gain
3301 stringlen
= (256 - deferred_len
);
3302 stringlen
+= cscipher
->blksize
- 1;
3303 stringlen
-= (stringlen
% cscipher
->blksize
);
3306 * Temporarily disable actual compression,
3307 * so we can guarantee to get this string
3308 * exactly the length we want it. The
3309 * compression-disabling routine should
3310 * return an integer indicating how many
3311 * bytes we should adjust our string length
3314 stringlen
-= cscomp
->disable_compression();
3316 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3317 ssh2_pkt_addstring_start();
3318 for (i
= 0; i
< stringlen
; i
++) {
3319 char c
= (char)random_byte();
3320 ssh2_pkt_addstring_data(&c
, 1);
3324 ssh_pkt_defersend();
3325 logevent("Sent password");
3326 type
= AUTH_TYPE_PASSWORD
;
3328 c_write_str("No supported authentication methods left to try!\r\n");
3329 logevent("No supported authentications offered. Disconnecting");
3330 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3331 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3332 ssh2_pkt_addstring("No supported authentication methods available");
3333 ssh2_pkt_addstring("en"); /* language tag */
3335 ssh_state
= SSH_STATE_CLOSED
;
3339 } while (!we_are_in
);
3342 * Now we're authenticated for the connection protocol. The
3343 * connection protocol will automatically have started at this
3344 * point; there's no need to send SERVICE_REQUEST.
3348 * So now create a channel with a session in it.
3350 mainchan
= smalloc(sizeof(struct ssh_channel
));
3351 mainchan
->localid
= 100; /* as good as any */
3352 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
3353 ssh2_pkt_addstring("session");
3354 ssh2_pkt_adduint32(mainchan
->localid
);
3355 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3356 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3358 crWaitUntilV(ispkt
);
3359 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3360 bombout(("Server refused to open a session"));
3362 /* FIXME: error data comes back in FAILURE packet */
3364 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
3365 bombout(("Server's channel confirmation cited wrong channel"));
3368 mainchan
->remoteid
= ssh2_pkt_getuint32();
3369 mainchan
->type
= CHAN_MAINSESSION
;
3370 mainchan
->closes
= 0;
3371 mainchan
->v2
.remwindow
= ssh2_pkt_getuint32();
3372 mainchan
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3373 mainchan
->v2
.outbuffer
= NULL
;
3374 mainchan
->v2
.outbuflen
= mainchan
->v2
.outbufsize
= 0;
3375 ssh_channels
= newtree234(ssh_channelcmp
);
3376 add234(ssh_channels
, mainchan
);
3377 logevent("Opened channel for session");
3380 * Potentially enable X11 forwarding.
3382 if (cfg
.x11_forward
) {
3383 char proto
[20], data
[64];
3384 logevent("Requesting X11 forwarding");
3385 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
3386 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3387 ssh2_pkt_adduint32(mainchan
->remoteid
);
3388 ssh2_pkt_addstring("x11-req");
3389 ssh2_pkt_addbool(1); /* want reply */
3390 ssh2_pkt_addbool(0); /* many connections */
3391 ssh2_pkt_addstring(proto
);
3392 ssh2_pkt_addstring(data
);
3393 ssh2_pkt_adduint32(0); /* screen number */
3397 crWaitUntilV(ispkt
);
3398 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3399 unsigned i
= ssh2_pkt_getuint32();
3400 struct ssh_channel
*c
;
3401 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3403 continue; /* nonexistent channel */
3404 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3406 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3408 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3409 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3410 bombout(("Server got confused by X11 forwarding request"));
3413 logevent("X11 forwarding refused");
3415 logevent("X11 forwarding enabled");
3416 ssh_X11_fwd_enabled
= TRUE
;
3421 * Potentially enable agent forwarding.
3423 if (cfg
.agentfwd
&& agent_exists()) {
3424 char proto
[20], data
[64];
3425 logevent("Requesting OpenSSH-style agent forwarding");
3426 x11_invent_auth(proto
, sizeof(proto
), data
, sizeof(data
));
3427 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3428 ssh2_pkt_adduint32(mainchan
->remoteid
);
3429 ssh2_pkt_addstring("auth-agent-req@openssh.com");
3430 ssh2_pkt_addbool(1); /* want reply */
3434 crWaitUntilV(ispkt
);
3435 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3436 unsigned i
= ssh2_pkt_getuint32();
3437 struct ssh_channel
*c
;
3438 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3440 continue; /* nonexistent channel */
3441 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3443 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3445 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3446 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3447 bombout(("Server got confused by agent forwarding request"));
3450 logevent("Agent forwarding refused");
3452 logevent("Agent forwarding enabled");
3453 ssh_agentfwd_enabled
= TRUE
;
3458 * Now allocate a pty for the session.
3461 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3462 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
3463 ssh2_pkt_addstring("pty-req");
3464 ssh2_pkt_addbool(1); /* want reply */
3465 ssh2_pkt_addstring(cfg
.termtype
);
3466 ssh2_pkt_adduint32(cols
);
3467 ssh2_pkt_adduint32(rows
);
3468 ssh2_pkt_adduint32(0); /* pixel width */
3469 ssh2_pkt_adduint32(0); /* pixel height */
3470 ssh2_pkt_addstring_start();
3471 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
3473 ssh_state
= SSH_STATE_INTERMED
;
3476 crWaitUntilV(ispkt
);
3477 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3478 unsigned i
= ssh2_pkt_getuint32();
3479 struct ssh_channel
*c
;
3480 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3482 continue; /* nonexistent channel */
3483 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3485 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3487 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3488 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3489 bombout(("Server got confused by pty request"));
3492 c_write_str("Server refused to allocate pty\r\n");
3493 ssh_editing
= ssh_echoing
= 1;
3495 logevent("Allocated pty");
3498 ssh_editing
= ssh_echoing
= 1;
3502 * Start a shell or a remote command.
3504 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3505 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
3506 if (cfg
.ssh_subsys
) {
3507 ssh2_pkt_addstring("subsystem");
3508 ssh2_pkt_addbool(1); /* want reply */
3509 ssh2_pkt_addstring(cfg
.remote_cmd
);
3510 } else if (*cfg
.remote_cmd
) {
3511 ssh2_pkt_addstring("exec");
3512 ssh2_pkt_addbool(1); /* want reply */
3513 ssh2_pkt_addstring(cfg
.remote_cmd
);
3515 ssh2_pkt_addstring("shell");
3516 ssh2_pkt_addbool(1); /* want reply */
3520 crWaitUntilV(ispkt
);
3521 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3522 unsigned i
= ssh2_pkt_getuint32();
3523 struct ssh_channel
*c
;
3524 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3526 continue; /* nonexistent channel */
3527 c
->v2
.remwindow
+= ssh2_pkt_getuint32();
3529 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3530 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
3531 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
3532 bombout(("Server got confused by shell/command request"));
3535 bombout(("Server refused to start a shell/command"));
3538 logevent("Started a shell/command");
3541 ssh_state
= SSH_STATE_SESSION
;
3545 ssh_special(TS_EOF
);
3550 ldisc_send(NULL
, 0); /* cause ldisc to notice changes */
3553 static int try_send
;
3557 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
3558 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
3561 unsigned i
= ssh2_pkt_getuint32();
3562 struct ssh_channel
*c
;
3563 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3565 continue; /* nonexistent channel */
3566 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
3567 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
3568 continue; /* extended but not stderr */
3569 ssh2_pkt_getstring(&data
, &length
);
3572 case CHAN_MAINSESSION
:
3573 from_backend(pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
,
3577 x11_send(c
->u
.x11
.s
, data
, length
);
3580 while (length
> 0) {
3581 if (c
->u
.a
.lensofar
< 4) {
3582 int l
= min(4 - c
->u
.a
.lensofar
, length
);
3583 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, data
, l
);
3584 data
+= l
; length
-= l
; c
->u
.a
.lensofar
+= l
;
3586 if (c
->u
.a
.lensofar
== 4) {
3587 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
3588 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3589 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3591 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
3592 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3594 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, data
, l
);
3595 data
+= l
; length
-= l
; c
->u
.a
.lensofar
+= l
;
3597 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3598 void *reply
, *sentreply
;
3600 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
3605 /* Fake SSH_AGENT_FAILURE. */
3606 sentreply
= "\0\0\0\1\5";
3609 ssh2_add_channel_data(c
, sentreply
, replylen
);
3613 sfree(c
->u
.a
.message
);
3614 c
->u
.a
.lensofar
= 0;
3620 * Enlarge the window again at the remote
3621 * side, just in case it ever runs down and
3622 * they fail to send us any more data.
3624 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
3625 ssh2_pkt_adduint32(c
->remoteid
);
3626 ssh2_pkt_adduint32(length
);
3629 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
3630 ssh_state
= SSH_STATE_CLOSED
;
3631 logevent("Received disconnect message");
3633 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
3634 continue; /* exit status et al; ignore (FIXME?) */
3635 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
3636 unsigned i
= ssh2_pkt_getuint32();
3637 struct ssh_channel
*c
;
3639 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3641 continue; /* nonexistent channel */
3643 if (c
->type
== CHAN_X11
) {
3645 * Remote EOF on an X11 channel means we should
3646 * wrap up and close the channel ourselves.
3648 x11_close(c
->u
.x11
.s
);
3650 } else if (c
->type
== CHAN_AGENT
) {
3653 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
3654 unsigned i
= ssh2_pkt_getuint32();
3655 struct ssh_channel
*c
;
3658 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3660 continue; /* nonexistent channel */
3661 if (c
->closes
== 0) {
3662 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
3663 ssh2_pkt_adduint32(c
->remoteid
);
3666 /* Do pre-close processing on the channel. */
3668 case CHAN_MAINSESSION
:
3669 break; /* nothing to see here, move along */
3675 del234(ssh_channels
, c
);
3676 sfree(c
->v2
.outbuffer
);
3680 * See if that was the last channel left open.
3682 c
= first234(ssh_channels
, &e
);
3684 logevent("All channels closed. Disconnecting");
3685 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
3686 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION
);
3687 ssh2_pkt_addstring("All open channels closed");
3688 ssh2_pkt_addstring("en"); /* language tag */
3690 ssh_state
= SSH_STATE_CLOSED
;
3693 continue; /* remote sends close; ignore (FIXME) */
3694 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
3695 unsigned i
= ssh2_pkt_getuint32();
3696 struct ssh_channel
*c
;
3697 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
3699 continue; /* nonexistent channel */
3700 mainchan
->v2
.remwindow
+= ssh2_pkt_getuint32();
3702 } else if (pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
3706 struct ssh_channel
*c
;
3707 ssh2_pkt_getstring(&type
, &typelen
);
3708 c
= smalloc(sizeof(struct ssh_channel
));
3710 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
3711 if (!ssh_X11_fwd_enabled
)
3712 error
= "X11 forwarding is not enabled";
3713 else if ( x11_init(&c
->u
.x11
.s
, cfg
.x11_display
, c
) != NULL
) {
3714 error
= "Unable to open an X11 connection";
3718 } else if (typelen
== 22 &&
3719 !memcmp(type
, "auth-agent@openssh.com", 3)) {
3720 if (!ssh_agentfwd_enabled
)
3721 error
= "Agent forwarding is not enabled";
3723 c
->type
= CHAN_AGENT
; /* identify channel type */
3724 c
->u
.a
.lensofar
= 0;
3727 error
= "Unsupported channel type requested";
3730 c
->remoteid
= ssh2_pkt_getuint32();
3732 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
3733 ssh2_pkt_adduint32(c
->remoteid
);
3734 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED
);
3735 ssh2_pkt_addstring(error
);
3736 ssh2_pkt_addstring("en"); /* language tag */
3740 struct ssh_channel
*d
;
3744 for (i
=1, d
= first234(ssh_channels
, &e
); d
;
3747 break; /* found a free number */
3752 c
->v2
.remwindow
= ssh2_pkt_getuint32();
3753 c
->v2
.remmaxpkt
= ssh2_pkt_getuint32();
3754 c
->v2
.outbuffer
= NULL
;
3755 c
->v2
.outbuflen
= c
->v2
.outbufsize
= 0;
3756 add234(ssh_channels
, c
);
3757 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
3758 ssh2_pkt_adduint32(c
->remoteid
);
3759 ssh2_pkt_adduint32(c
->localid
);
3760 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
3761 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
3765 bombout(("Strange packet received: type %d", pktin
.type
));
3770 * We have spare data. Add it to the channel buffer.
3772 ssh2_add_channel_data(mainchan
, in
, inlen
);
3777 struct ssh_channel
*c
;
3779 * Try to send data on all channels if we can.
3781 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
))
3790 * Handle the top-level SSH2 protocol.
3792 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
3794 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
3796 do_ssh2_authconn(in
, inlen
, ispkt
);
3800 * Called to set up the connection.
3802 * Returns an error message, or NULL on success.
3804 static char *ssh_init (char *host
, int port
, char **realhost
) {
3808 if(crypto_startup() == 0)
3809 return "Microsoft high encryption pack not installed!";
3816 p
= connect_to_host(host
, port
, realhost
);
3824 * Called to send data down the Telnet connection.
3826 static void ssh_send (char *buf
, int len
) {
3827 if (s
== NULL
|| ssh_protocol
== NULL
)
3830 ssh_protocol(buf
, len
, 0);
3834 * Called to set the size of the window from SSH's POV.
3836 static void ssh_size(void) {
3837 switch (ssh_state
) {
3838 case SSH_STATE_BEFORE_SIZE
:
3839 case SSH_STATE_PREPACKET
:
3840 case SSH_STATE_CLOSED
:
3841 break; /* do nothing */
3842 case SSH_STATE_INTERMED
:
3843 size_needed
= TRUE
; /* buffer for later */
3845 case SSH_STATE_SESSION
:
3847 if (ssh_version
== 1) {
3848 send_packet(SSH1_CMSG_WINDOW_SIZE
,
3849 PKT_INT
, rows
, PKT_INT
, cols
,
3850 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
3852 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
3853 ssh2_pkt_adduint32(mainchan
->remoteid
);
3854 ssh2_pkt_addstring("window-change");
3855 ssh2_pkt_addbool(0);
3856 ssh2_pkt_adduint32(cols
);
3857 ssh2_pkt_adduint32(rows
);
3858 ssh2_pkt_adduint32(0);
3859 ssh2_pkt_adduint32(0);
3868 * Send Telnet special codes. TS_EOF is useful for `plink', so you
3869 * can send an EOF and collect resulting output (e.g. `plink
3872 static void ssh_special (Telnet_Special code
) {
3873 if (code
== TS_EOF
) {
3874 if (ssh_state
!= SSH_STATE_SESSION
) {
3876 * Buffer the EOF in case we are pre-SESSION, so we can
3877 * send it as soon as we reach SESSION.
3883 if (ssh_version
== 1) {
3884 send_packet(SSH1_CMSG_EOF
, PKT_END
);
3886 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
3887 ssh2_pkt_adduint32(mainchan
->remoteid
);
3890 logevent("Sent EOF message");
3891 } else if (code
== TS_PING
) {
3892 if (ssh_state
== SSH_STATE_CLOSED
|| ssh_state
== SSH_STATE_PREPACKET
)
3894 if (ssh_version
== 1) {
3895 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
3897 ssh2_pkt_init(SSH2_MSG_IGNORE
);
3898 ssh2_pkt_addstring_start();
3906 static Socket
ssh_socket(void) { return s
; }
3908 static int ssh_sendok(void) { return ssh_send_ok
; }
3910 static int ssh_ldisc(int option
) {
3911 if (option
== LD_ECHO
) return ssh_echoing
;
3912 if (option
== LD_EDIT
) return ssh_editing
;
3916 Backend ssh_backend
= {