24 #define logevent(s) { logevent(s); \
25 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
26 fprintf(stderr, "%s\n", s); }
28 #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, closesocket(s), \
29 s = INVALID_SOCKET, connection_fatal msg )
31 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
32 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
33 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
34 #define SSH1_CMSG_USER 4 /* 0x4 */
35 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
36 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
37 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
38 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
39 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
40 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
41 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
42 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
43 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
44 #define SSH1_SMSG_FAILURE 15 /* 0xf */
45 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
46 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
47 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
48 #define SSH1_CMSG_EOF 19 /* 0x13 */
49 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
50 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
51 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
52 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
53 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
54 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
55 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
56 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
57 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
58 #define SSH1_MSG_IGNORE 32 /* 0x20 */
59 #define SSH1_MSG_DEBUG 36 /* 0x24 */
60 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
61 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
62 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
63 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
64 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
65 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
67 #define SSH1_AUTH_TIS 5 /* 0x5 */
68 #define SSH1_AUTH_CCARD 16 /* 0x10 */
70 #define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
71 #define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
72 #define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
73 #define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
74 #define SSH_AGENT_FAILURE 5 /* 0x5 */
75 #define SSH_AGENT_SUCCESS 6 /* 0x6 */
76 #define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
77 #define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
79 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
80 #define SSH2_MSG_IGNORE 2 /* 0x2 */
81 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
82 #define SSH2_MSG_DEBUG 4 /* 0x4 */
83 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
84 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
85 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
86 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
87 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
88 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
89 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
90 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
91 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
92 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
93 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
94 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
95 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
96 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
97 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
98 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
99 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
100 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
101 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
102 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
103 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
104 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
105 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
106 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
107 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
108 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
110 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
111 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
112 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
113 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
115 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
117 #define GET_32BIT(cp) \
118 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
119 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
120 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
121 ((unsigned long)(unsigned char)(cp)[3]))
123 #define PUT_32BIT(cp, value) { \
124 (cp)[0] = (unsigned char)((value) >> 24); \
125 (cp)[1] = (unsigned char)((value) >> 16); \
126 (cp)[2] = (unsigned char)((value) >> 8); \
127 (cp)[3] = (unsigned char)(value); }
129 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
131 /* Coroutine mechanics for the sillier bits of the code */
132 #define crBegin1 static int crLine = 0;
133 #define crBegin2 switch(crLine) { case 0:;
134 #define crBegin crBegin1; crBegin2;
135 #define crFinish(z) } crLine = 0; return (z)
136 #define crFinishV } crLine = 0; return
137 #define crReturn(z) \
139 crLine=__LINE__; return (z); case __LINE__:;\
143 crLine=__LINE__; return; case __LINE__:;\
145 #define crStop(z) do{ crLine = 0; return (z); }while(0)
146 #define crStopV do{ crLine = 0; return; }while(0)
147 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
148 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
150 extern const struct ssh_cipher ssh_3des
;
151 extern const struct ssh_cipher ssh_3des_ssh2
;
152 extern const struct ssh_cipher ssh_des
;
153 extern const struct ssh_cipher ssh_blowfish_ssh1
;
154 extern const struct ssh_cipher ssh_blowfish_ssh2
;
157 * Ciphers for SSH2. We miss out single-DES because it isn't
158 * supported; also 3DES and Blowfish are both done differently from
159 * SSH1. (3DES uses outer chaining; Blowfish has the opposite
160 * endianness and different-sized keys.)
162 const static struct ssh_cipher
*ciphers
[] = { &ssh_blowfish_ssh2
, &ssh_3des_ssh2
};
164 extern const struct ssh_kex ssh_diffiehellman
;
165 const static struct ssh_kex
*kex_algs
[] = { &ssh_diffiehellman
};
167 extern const struct ssh_hostkey ssh_dss
;
168 const static struct ssh_hostkey
*hostkey_algs
[] = { &ssh_dss
};
170 extern const struct ssh_mac ssh_md5
, ssh_sha1
, ssh_sha1_buggy
;
172 static void nullmac_key(unsigned char *key
) { }
173 static void nullmac_generate(unsigned char *blk
, int len
, unsigned long seq
) { }
174 static int nullmac_verify(unsigned char *blk
, int len
, unsigned long seq
) { return 1; }
175 const static struct ssh_mac ssh_mac_none
= {
176 nullmac_key
, nullmac_key
, nullmac_generate
, nullmac_verify
, "none", 0
178 const static struct ssh_mac
*macs
[] = {
179 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
};
180 const static struct ssh_mac
*buggymacs
[] = {
181 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
};
183 const static struct ssh_compress ssh_comp_none
= {
186 const static struct ssh_compress
*compressions
[] = { &ssh_comp_none
};
189 * 2-3-4 tree storing channels.
192 unsigned remoteid
, localid
;
196 struct ssh_agent_channel
{
197 unsigned char *message
;
198 unsigned char msglen
[4];
199 int lensofar
, totallen
;
201 struct ssh2_data_channel
{
202 unsigned char *outbuffer
;
203 unsigned outbuflen
, outbufsize
;
204 unsigned remwindow
, remmaxpkt
;
218 static SHA_State exhash
;
220 static SOCKET s
= INVALID_SOCKET
;
222 static unsigned char session_key
[32];
223 static const struct ssh_cipher
*cipher
= NULL
;
224 static const struct ssh_cipher
*cscipher
= NULL
;
225 static const struct ssh_cipher
*sccipher
= NULL
;
226 static const struct ssh_mac
*csmac
= NULL
;
227 static const struct ssh_mac
*scmac
= NULL
;
228 static const struct ssh_compress
*cscomp
= NULL
;
229 static const struct ssh_compress
*sccomp
= NULL
;
230 static const struct ssh_kex
*kex
= NULL
;
231 static const struct ssh_hostkey
*hostkey
= NULL
;
232 int (*ssh_get_password
)(const char *prompt
, char *str
, int maxlen
) = NULL
;
234 static char *savedhost
;
235 static int savedport
;
236 static int ssh_send_ok
;
238 static tree234
*ssh_channels
; /* indexed by local id */
239 static struct ssh_channel
*mainchan
; /* primary session channel */
242 SSH_STATE_BEFORE_SIZE
,
246 } ssh_state
= SSH_STATE_BEFORE_SIZE
;
248 static int size_needed
= FALSE
;
250 static struct Packet pktin
= { 0, 0, NULL
, NULL
, 0 };
251 static struct Packet pktout
= { 0, 0, NULL
, NULL
, 0 };
253 static int ssh_version
;
254 static void (*ssh_protocol
)(unsigned char *in
, int inlen
, int ispkt
);
255 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
);
256 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
);
257 static void ssh_size(void);
259 static int (*s_rdpkt
)(unsigned char **data
, int *datalen
);
261 static struct rdpkt1_state_tag
{
262 long len
, pad
, biglen
, to_read
;
263 unsigned long realcrc
, gotcrc
;
269 static struct rdpkt2_state_tag
{
270 long len
, pad
, payload
, packetlen
, maclen
;
273 unsigned long incoming_sequence
;
276 static int ssh_channelcmp(void *av
, void *bv
) {
277 struct ssh_channel
*a
= (struct ssh_channel
*)av
;
278 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
279 if (a
->localid
< b
->localid
) return -1;
280 if (a
->localid
> b
->localid
) return +1;
283 static int ssh_channelfind(void *av
, void *bv
) {
284 unsigned *a
= (unsigned *)av
;
285 struct ssh_channel
*b
= (struct ssh_channel
*)bv
;
286 if (*a
< b
->localid
) return -1;
287 if (*a
> b
->localid
) return +1;
291 static void s_write (char *buf
, int len
) {
293 int i
= send (s
, buf
, len
, 0);
296 bombout(("Lost connection while sending"));
304 static int s_read (char *buf
, int len
) {
307 int i
= recv (s
, buf
, len
, 0);
310 len
-= i
, buf
+= i
, ret
+= i
;
317 static void c_write (char *buf
, int len
) {
318 if ((flags
& FLAG_STDERR
)) {
320 for (i
= 0; i
< len
; i
++)
322 fputc(buf
[i
], stderr
);
329 static void c_writedata (char *buf
, int len
) {
335 * Collect incoming data in the incoming packet buffer.
336 * Decipher and verify the packet when it is completely read.
337 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
338 * Update the *data and *datalen variables.
339 * Return the additional nr of bytes needed, or 0 when
340 * a complete packet is available.
342 static int ssh1_rdpkt(unsigned char **data
, int *datalen
)
344 struct rdpkt1_state_tag
*st
= &rdpkt1_state
;
353 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
354 while ((*datalen
) == 0)
356 st
->len
= (st
->len
<< 8) + **data
;
357 (*data
)++, (*datalen
)--;
361 if (st
->len
== 0x52656d6f) { /* "Remo"te server has closed ... */
362 st
->len
= 0x300; /* big enough to carry to end */
366 st
->pad
= 8 - (st
->len
% 8);
367 st
->biglen
= st
->len
+ st
->pad
;
368 pktin
.length
= st
->len
- 5;
370 if (pktin
.maxlen
< st
->biglen
) {
371 pktin
.maxlen
= st
->biglen
;
372 pktin
.data
= (pktin
.data
== NULL ?
malloc(st
->biglen
+APIEXTRA
) :
373 realloc(pktin
.data
, st
->biglen
+APIEXTRA
));
375 fatalbox("Out of memory");
378 st
->to_read
= st
->biglen
;
380 while (st
->to_read
> 0) {
381 st
->chunk
= st
->to_read
;
382 while ((*datalen
) == 0)
383 crReturn(st
->to_read
);
384 if (st
->chunk
> (*datalen
))
385 st
->chunk
= (*datalen
);
386 memcpy(st
->p
, *data
, st
->chunk
);
388 *datalen
-= st
->chunk
;
390 st
->to_read
-= st
->chunk
;
394 cipher
->decrypt(pktin
.data
, st
->biglen
);
396 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
397 for (st
->i
= 0; st
->i
< st
->biglen
; st
->i
++)
398 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
402 pktin
.type
= pktin
.data
[st
->pad
];
403 pktin
.body
= pktin
.data
+ st
->pad
+ 1;
405 st
->realcrc
= crc32(pktin
.data
, st
->biglen
-4);
406 st
->gotcrc
= GET_32BIT(pktin
.data
+st
->biglen
-4);
407 if (st
->gotcrc
!= st
->realcrc
) {
408 bombout(("Incorrect CRC received on packet"));
412 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
413 pktin
.type
== SSH1_SMSG_STDERR_DATA
||
414 pktin
.type
== SSH1_MSG_DEBUG
||
415 pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
416 pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
417 long strlen
= GET_32BIT(pktin
.body
);
418 if (strlen
+ 4 != pktin
.length
) {
419 bombout(("Received data packet with bogus string length"));
424 if (pktin
.type
== SSH1_MSG_DEBUG
) {
425 /* log debug message */
427 int strlen
= GET_32BIT(pktin
.body
);
428 strcpy(buf
, "Remote: ");
429 if (strlen
> 70) strlen
= 70;
430 memcpy(buf
+8, pktin
.body
+4, strlen
);
431 buf
[8+strlen
] = '\0';
434 } else if (pktin
.type
== SSH1_MSG_IGNORE
) {
442 static int ssh2_rdpkt(unsigned char **data
, int *datalen
)
444 struct rdpkt2_state_tag
*st
= &rdpkt2_state
;
452 st
->cipherblk
= sccipher
->blksize
;
455 if (st
->cipherblk
< 8)
458 if (pktin
.maxlen
< st
->cipherblk
) {
459 pktin
.maxlen
= st
->cipherblk
;
460 pktin
.data
= (pktin
.data
== NULL ?
malloc(st
->cipherblk
+APIEXTRA
) :
461 realloc(pktin
.data
, st
->cipherblk
+APIEXTRA
));
463 fatalbox("Out of memory");
467 * Acquire and decrypt the first block of the packet. This will
468 * contain the length and padding details.
470 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
471 while ((*datalen
) == 0)
472 crReturn(st
->cipherblk
-st
->i
);
473 pktin
.data
[st
->i
] = *(*data
)++;
477 if (!memcmp(pktin
.data
, "Remo", 4)) {/* "Remo"te server has closed ... */
482 sccipher
->decrypt(pktin
.data
, st
->cipherblk
);
485 * Now get the length and padding figures.
487 st
->len
= GET_32BIT(pktin
.data
);
488 st
->pad
= pktin
.data
[4];
491 * This enables us to deduce the payload length.
493 st
->payload
= st
->len
- st
->pad
- 1;
495 pktin
.length
= st
->payload
+ 5;
498 * So now we can work out the total packet length.
500 st
->packetlen
= st
->len
+ 4;
501 st
->maclen
= scmac ? scmac
->len
: 0;
504 * Adjust memory allocation if packet is too big.
506 if (pktin
.maxlen
< st
->packetlen
+st
->maclen
) {
507 pktin
.maxlen
= st
->packetlen
+st
->maclen
;
508 pktin
.data
= (pktin
.data
== NULL ?
malloc(pktin
.maxlen
+APIEXTRA
) :
509 realloc(pktin
.data
, pktin
.maxlen
+APIEXTRA
));
511 fatalbox("Out of memory");
515 * Read and decrypt the remainder of the packet.
517 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
; st
->i
++) {
518 while ((*datalen
) == 0)
519 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
520 pktin
.data
[st
->i
] = *(*data
)++;
523 /* Decrypt everything _except_ the MAC. */
525 sccipher
->decrypt(pktin
.data
+ st
->cipherblk
,
526 st
->packetlen
- st
->cipherblk
);
529 debug(("Got packet len=%d pad=%d\r\n", st
->len
, st
->pad
));
530 for (st
->i
= 0; st
->i
< st
->packetlen
; st
->i
++)
531 debug((" %02x", (unsigned char)pktin
.data
[st
->i
]));
538 if (scmac
&& !scmac
->verify(pktin
.data
, st
->len
+4, st
->incoming_sequence
)) {
539 bombout(("Incorrect MAC received on packet"));
542 st
->incoming_sequence
++; /* whether or not we MACed */
545 pktin
.type
= pktin
.data
[5];
547 if (pktin
.type
== SSH2_MSG_IGNORE
|| pktin
.type
== SSH2_MSG_DEBUG
)
548 goto next_packet
; /* FIXME: print DEBUG message */
553 static void ssh_gotdata(unsigned char *data
, int datalen
)
555 while (datalen
> 0) {
556 if ( s_rdpkt(&data
, &datalen
) == 0 ) {
557 ssh_protocol(NULL
, 0, 1);
558 if (ssh_state
== SSH_STATE_CLOSED
) {
566 static void s_wrpkt_start(int type
, int len
) {
569 len
+= 5; /* type and CRC */
573 pktout
.length
= len
-5;
574 if (pktout
.maxlen
< biglen
) {
575 pktout
.maxlen
= biglen
;
577 /* Allocate enough buffer space for extra block
578 * for MS CryptEncrypt() */
579 pktout
.data
= (pktout
.data
== NULL ?
malloc(biglen
+12) :
580 realloc(pktout
.data
, biglen
+12));
582 pktout
.data
= (pktout
.data
== NULL ?
malloc(biglen
+4) :
583 realloc(pktout
.data
, biglen
+4));
586 fatalbox("Out of memory");
590 pktout
.body
= pktout
.data
+4+pad
+1;
593 static void s_wrpkt(void) {
594 int pad
, len
, biglen
, i
;
597 len
= pktout
.length
+ 5; /* type and CRC */
601 pktout
.body
[-1] = pktout
.type
;
602 for (i
=0; i
<pad
; i
++)
603 pktout
.data
[i
+4] = random_byte();
604 crc
= crc32(pktout
.data
+4, biglen
-4);
605 PUT_32BIT(pktout
.data
+biglen
, crc
);
606 PUT_32BIT(pktout
.data
, len
);
609 debug(("Sending packet len=%d\r\n", biglen
+4));
610 for (i
= 0; i
< biglen
+4; i
++)
611 debug((" %02x", (unsigned char)pktout
.data
[i
]));
615 cipher
->encrypt(pktout
.data
+4, biglen
);
617 s_write(pktout
.data
, biglen
+4);
621 * Construct a packet with the specified contents and
622 * send it to the server.
624 static void send_packet(int pkttype
, ...)
627 unsigned char *p
, *argp
, argchar
;
628 unsigned long argint
;
629 int pktlen
, argtype
, arglen
;
633 va_start(args
, pkttype
);
634 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
637 (void) va_arg(args
, int);
641 (void) va_arg(args
, char);
645 (void) va_arg(args
, unsigned char *);
646 arglen
= va_arg(args
, int);
650 argp
= va_arg(args
, unsigned char *);
651 arglen
= strlen(argp
);
652 pktlen
+= 4 + arglen
;
655 bn
= va_arg(args
, Bignum
);
656 pktlen
+= ssh1_bignum_length(bn
);
664 s_wrpkt_start(pkttype
, pktlen
);
667 va_start(args
, pkttype
);
668 while ((argtype
= va_arg(args
, int)) != PKT_END
) {
671 argint
= va_arg(args
, int);
672 PUT_32BIT(p
, argint
);
676 argchar
= va_arg(args
, unsigned char);
681 argp
= va_arg(args
, unsigned char *);
682 arglen
= va_arg(args
, int);
683 memcpy(p
, argp
, arglen
);
687 argp
= va_arg(args
, unsigned char *);
688 arglen
= strlen(argp
);
689 PUT_32BIT(p
, arglen
);
690 memcpy(p
+ 4, argp
, arglen
);
694 bn
= va_arg(args
, Bignum
);
695 p
+= ssh1_write_bignum(p
, bn
);
706 * Connect to specified host and port.
707 * Returns an error message, or NULL on success.
708 * Also places the canonical host name into `realhost'.
710 static char *connect_to_host(char *host
, int port
, char **realhost
)
720 savedhost
= malloc(1+strlen(host
));
722 fatalbox("Out of memory");
723 strcpy(savedhost
, host
);
726 port
= 22; /* default ssh port */
739 if ( (a
= inet_addr(host
)) == (unsigned long) INADDR_NONE
) {
740 if ( (h
= gethostbyname(host
)) == NULL
)
741 switch (WSAGetLastError()) {
742 case WSAENETDOWN
: return "Network is down";
743 case WSAHOST_NOT_FOUND
: case WSANO_DATA
:
744 return "Host does not exist";
745 case WSATRY_AGAIN
: return "Host not found";
746 default: return "gethostbyname: unknown error";
748 memcpy (&a
, h
->h_addr
, sizeof(a
));
749 *realhost
= h
->h_name
;
760 s
= socket(AF_INET
, SOCK_STREAM
, 0);
761 if (s
== INVALID_SOCKET
)
762 switch (WSAGetLastError()) {
763 case WSAENETDOWN
: return "Network is down";
764 case WSAEAFNOSUPPORT
: return "TCP/IP support not present";
765 default: return "socket(): unknown error";
769 * Bind to local address.
771 addr
.sin_family
= AF_INET
;
772 addr
.sin_addr
.s_addr
= htonl(INADDR_ANY
);
773 addr
.sin_port
= htons(0);
774 if (bind (s
, (struct sockaddr
*)&addr
, sizeof(addr
)) == SOCKET_ERROR
)
775 switch (WSAGetLastError()) {
776 case WSAENETDOWN
: return "Network is down";
777 default: return "bind(): unknown error";
781 * Connect to remote address.
783 addr
.sin_addr
.s_addr
= htonl(a
);
784 addr
.sin_port
= htons((short)port
);
785 if (connect (s
, (struct sockaddr
*)&addr
, sizeof(addr
)) == SOCKET_ERROR
)
786 switch (WSAGetLastError()) {
787 case WSAENETDOWN
: return "Network is down";
788 case WSAECONNREFUSED
: return "Connection refused";
789 case WSAENETUNREACH
: return "Network is unreachable";
790 case WSAEHOSTUNREACH
: return "No route to host";
791 default: return "connect(): unknown error";
795 send(s
, "connect ", 8, 0);
796 send(s
, FWhost
, strlen(FWhost
), 0);
799 sprintf(buf
, " %d\n", FWport
);
800 send (s
, buf
, strlen(buf
), 0);
807 static int ssh_versioncmp(char *a
, char *b
) {
809 unsigned long av
, bv
;
811 av
= strtoul(a
, &ae
, 10);
812 bv
= strtoul(b
, &be
, 10);
813 if (av
!= bv
) return (av
< bv ?
-1 : +1);
814 if (*ae
== '.') ae
++;
815 if (*be
== '.') be
++;
816 av
= strtoul(ae
, &ae
, 10);
817 bv
= strtoul(be
, &be
, 10);
818 if (av
!= bv
) return (av
< bv ?
-1 : +1);
824 * Utility routine for putting an SSH-protocol `string' into a SHA
828 static void sha_string(SHA_State
*s
, void *str
, int len
) {
829 unsigned char lenblk
[4];
830 PUT_32BIT(lenblk
, len
);
831 SHA_Bytes(s
, lenblk
, 4);
832 SHA_Bytes(s
, str
, len
);
836 * SSH2 packet construction functions.
838 static void ssh2_pkt_adddata(void *data
, int len
) {
839 pktout
.length
+= len
;
840 if (pktout
.maxlen
< pktout
.length
) {
841 pktout
.maxlen
= pktout
.length
+ 256;
842 pktout
.data
= (pktout
.data
== NULL ?
malloc(pktout
.maxlen
+APIEXTRA
) :
843 realloc(pktout
.data
, pktout
.maxlen
+APIEXTRA
));
845 fatalbox("Out of memory");
847 memcpy(pktout
.data
+pktout
.length
-len
, data
, len
);
849 static void ssh2_pkt_addbyte(unsigned char byte
) {
850 ssh2_pkt_adddata(&byte
, 1);
852 static void ssh2_pkt_init(int pkt_type
) {
854 ssh2_pkt_addbyte((unsigned char)pkt_type
);
856 static void ssh2_pkt_addbool(unsigned char value
) {
857 ssh2_pkt_adddata(&value
, 1);
859 static void ssh2_pkt_adduint32(unsigned long value
) {
862 ssh2_pkt_adddata(x
, 4);
864 static void ssh2_pkt_addstring_start(void) {
865 ssh2_pkt_adduint32(0);
866 pktout
.savedpos
= pktout
.length
;
868 static void ssh2_pkt_addstring_str(char *data
) {
869 ssh2_pkt_adddata(data
, strlen(data
));
870 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
871 pktout
.length
- pktout
.savedpos
);
873 static void ssh2_pkt_addstring_data(char *data
, int len
) {
874 ssh2_pkt_adddata(data
, len
);
875 PUT_32BIT(pktout
.data
+ pktout
.savedpos
- 4,
876 pktout
.length
- pktout
.savedpos
);
878 static void ssh2_pkt_addstring(char *data
) {
879 ssh2_pkt_addstring_start();
880 ssh2_pkt_addstring_str(data
);
882 static char *ssh2_mpint_fmt(Bignum b
, int *len
) {
885 p
= malloc(n
* 2 + 1);
887 fatalbox("out of memory");
889 for (i
= 0; i
< n
; i
++) {
890 p
[i
*2+1] = (b
[n
-i
] >> 8) & 0xFF;
891 p
[i
*2+2] = (b
[n
-i
] ) & 0xFF;
894 while (p
[i
] == 0 && (p
[i
+1] & 0x80) == 0)
896 memmove(p
, p
+i
, n
*2+1-i
);
900 static void ssh2_pkt_addmp(Bignum b
) {
903 p
= ssh2_mpint_fmt(b
, &len
);
904 ssh2_pkt_addstring_start();
905 ssh2_pkt_addstring_data(p
, len
);
908 static void ssh2_pkt_send(void) {
909 int cipherblk
, maclen
, padding
, i
;
910 static unsigned long outgoing_sequence
= 0;
913 * Add padding. At least four bytes, and must also bring total
914 * length (minus MAC) up to a multiple of the block size.
916 cipherblk
= cipher ? cipher
->blksize
: 8; /* block size */
917 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
919 padding
+= (cipherblk
- (pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
920 pktout
.data
[4] = padding
;
921 for (i
= 0; i
< padding
; i
++)
922 pktout
.data
[pktout
.length
+ i
] = random_byte();
923 PUT_32BIT(pktout
.data
, pktout
.length
+ padding
- 4);
925 csmac
->generate(pktout
.data
, pktout
.length
+ padding
,
927 outgoing_sequence
++; /* whether or not we MACed */
930 debug(("Sending packet len=%d\r\n", pktout
.length
+padding
));
931 for (i
= 0; i
< pktout
.length
+padding
; i
++)
932 debug((" %02x", (unsigned char)pktout
.data
[i
]));
937 cscipher
->encrypt(pktout
.data
, pktout
.length
+ padding
);
938 maclen
= csmac ? csmac
->len
: 0;
940 s_write(pktout
.data
, pktout
.length
+ padding
+ maclen
);
944 void bndebug(char *string
, Bignum b
) {
947 p
= ssh2_mpint_fmt(b
, &len
);
948 debug(("%s", string
));
949 for (i
= 0; i
< len
; i
++)
950 debug((" %02x", p
[i
]));
956 static void sha_mpint(SHA_State
*s
, Bignum b
) {
959 p
= ssh2_mpint_fmt(b
, &len
);
960 sha_string(s
, p
, len
);
965 * SSH2 packet decode functions.
967 static unsigned long ssh2_pkt_getuint32(void) {
969 if (pktin
.length
- pktin
.savedpos
< 4)
970 return 0; /* arrgh, no way to decline (FIXME?) */
971 value
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
975 static void ssh2_pkt_getstring(char **p
, int *length
) {
977 if (pktin
.length
- pktin
.savedpos
< 4)
979 *length
= GET_32BIT(pktin
.data
+pktin
.savedpos
);
981 if (pktin
.length
- pktin
.savedpos
< *length
)
983 *p
= pktin
.data
+pktin
.savedpos
;
984 pktin
.savedpos
+= *length
;
986 static Bignum
ssh2_pkt_getmp(void) {
991 ssh2_pkt_getstring(&p
, &length
);
995 bombout(("internal error: Can't handle negative mpints"));
998 b
= newbn((length
+1)/2);
999 for (i
= 0; i
< length
; i
++) {
1002 b
[j
/2+1] |= ((unsigned char)p
[i
]) << 8;
1004 b
[j
/2+1] |= ((unsigned char)p
[i
]);
1009 static int do_ssh_init(void) {
1013 char vlog
[sizeof(vstring
)+20];
1018 while (s_read(&c
, 1) == 1) {
1019 if (c
== 'S' && i
< 2) i
++;
1020 else if (c
== 'S' && i
== 2) i
= 2;
1021 else if (c
== 'H' && i
== 2) break;
1025 if (s_read(&c
,1) != 1 || c
!= 'S') return 0;
1026 if (s_read(&c
,1) != 1 || c
!= 'S') return 0;
1027 if (s_read(&c
,1) != 1 || c
!= 'H') return 0;
1029 strcpy(vstring
, "SSH-");
1031 if (s_read(&c
,1) != 1 || c
!= '-') return 0;
1034 if (s_read(&c
,1) != 1)
1036 if (vsp
< vstring
+sizeof(vstring
)-1)
1042 } else if (i
< sizeof(version
)-1)
1049 rdpkt2_state
.incoming_sequence
= 0;
1052 sprintf(vlog
, "Server version: %s", vstring
);
1053 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1057 * Server version "1.99" means we can choose whether we use v1
1058 * or v2 protocol. Choice is based on cfg.sshprot.
1060 if (ssh_versioncmp(version
, cfg
.sshprot
== 1 ?
"2.0" : "1.99") >= 0) {
1062 * This is a v2 server. Begin v2 protocol.
1064 char *verstring
= "SSH-2.0-PuTTY";
1067 * Hash our version string and their version string.
1069 sha_string(&exhash
, verstring
, strlen(verstring
));
1070 sha_string(&exhash
, vstring
, strcspn(vstring
, "\r\n"));
1071 sprintf(vstring
, "%s\n", verstring
);
1072 sprintf(vlog
, "We claim version: %s", verstring
);
1074 logevent("Using SSH protocol version 2");
1075 s_write(vstring
, strlen(vstring
));
1076 ssh_protocol
= ssh2_protocol
;
1078 s_rdpkt
= ssh2_rdpkt
;
1081 * This is a v1 server. Begin v1 protocol.
1083 sprintf(vstring
, "SSH-%s-PuTTY\n",
1084 (ssh_versioncmp(version
, "1.5") <= 0 ? version
: "1.5"));
1085 sprintf(vlog
, "We claim version: %s", vstring
);
1086 vlog
[strcspn(vlog
, "\r\n")] = '\0';
1088 logevent("Using SSH protocol version 1");
1089 s_write(vstring
, strlen(vstring
));
1090 ssh_protocol
= ssh1_protocol
;
1092 s_rdpkt
= ssh1_rdpkt
;
1099 * Handle the key exchange and user authentication phases.
1101 static int do_ssh1_login(unsigned char *in
, int inlen
, int ispkt
)
1104 unsigned char *rsabuf
, *keystr1
, *keystr2
;
1105 unsigned char cookie
[8];
1106 struct RSAKey servkey
, hostkey
;
1107 struct MD5Context md5c
;
1108 static unsigned long supported_ciphers_mask
, supported_auths_mask
;
1109 static int tried_publickey
;
1110 static unsigned char session_id
[16];
1112 static char username
[100];
1116 if (!ispkt
) crWaitUntil(ispkt
);
1118 if (pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
1119 bombout(("Public key packet not received"));
1123 logevent("Received public keys");
1125 memcpy(cookie
, pktin
.body
, 8);
1127 i
= makekey(pktin
.body
+8, &servkey
, &keystr1
, 0);
1128 j
= makekey(pktin
.body
+8+i
, &hostkey
, &keystr2
, 0);
1131 * Log the host key fingerprint.
1135 logevent("Host key fingerprint is:");
1136 strcpy(logmsg
, " ");
1137 hostkey
.comment
= NULL
;
1138 rsa_fingerprint(logmsg
+strlen(logmsg
), sizeof(logmsg
)-strlen(logmsg
),
1143 supported_ciphers_mask
= GET_32BIT(pktin
.body
+12+i
+j
);
1144 supported_auths_mask
= GET_32BIT(pktin
.body
+16+i
+j
);
1147 MD5Update(&md5c
, keystr2
, hostkey
.bytes
);
1148 MD5Update(&md5c
, keystr1
, servkey
.bytes
);
1149 MD5Update(&md5c
, pktin
.body
, 8);
1150 MD5Final(session_id
, &md5c
);
1152 for (i
=0; i
<32; i
++)
1153 session_key
[i
] = random_byte();
1155 len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
1157 rsabuf
= malloc(len
);
1159 fatalbox("Out of memory");
1162 * Verify the host key.
1166 * First format the key into a string.
1168 int len
= rsastr_len(&hostkey
);
1169 char fingerprint
[100];
1170 char *keystr
= malloc(len
);
1172 fatalbox("Out of memory");
1173 rsastr_fmt(keystr
, &hostkey
);
1174 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
1175 verify_ssh_host_key(savedhost
, savedport
, "rsa", keystr
, fingerprint
);
1179 for (i
=0; i
<32; i
++) {
1180 rsabuf
[i
] = session_key
[i
];
1182 rsabuf
[i
] ^= session_id
[i
];
1185 if (hostkey
.bytes
> servkey
.bytes
) {
1186 rsaencrypt(rsabuf
, 32, &servkey
);
1187 rsaencrypt(rsabuf
, servkey
.bytes
, &hostkey
);
1189 rsaencrypt(rsabuf
, 32, &hostkey
);
1190 rsaencrypt(rsabuf
, hostkey
.bytes
, &servkey
);
1193 logevent("Encrypted session key");
1195 cipher_type
= cfg
.cipher
== CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH
:
1196 cfg
.cipher
== CIPHER_DES ? SSH_CIPHER_DES
:
1198 if ((supported_ciphers_mask
& (1 << cipher_type
)) == 0) {
1199 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1200 cipher_type
= SSH_CIPHER_3DES
;
1202 switch (cipher_type
) {
1203 case SSH_CIPHER_3DES
: logevent("Using 3DES encryption"); break;
1204 case SSH_CIPHER_DES
: logevent("Using single-DES encryption"); break;
1205 case SSH_CIPHER_BLOWFISH
: logevent("Using Blowfish encryption"); break;
1208 send_packet(SSH1_CMSG_SESSION_KEY
,
1209 PKT_CHAR
, cipher_type
,
1210 PKT_DATA
, cookie
, 8,
1211 PKT_CHAR
, (len
*8) >> 8, PKT_CHAR
, (len
*8) & 0xFF,
1212 PKT_DATA
, rsabuf
, len
,
1216 logevent("Trying to enable encryption...");
1220 cipher
= cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
1221 cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
1223 cipher
->sesskey(session_key
);
1227 if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1228 bombout(("Encryption not successfully enabled"));
1232 logevent("Successfully started encryption");
1238 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
1239 c_write("login as: ", 10);
1242 crWaitUntil(!ispkt
);
1243 while (inlen
--) switch (c
= *in
++) {
1250 c_write("\b \b", 3);
1256 c_write("\b \b", 3);
1265 if (((c
>= ' ' && c
<= '~') ||
1266 ((unsigned char)c
>= 160)) && pos
< 40) {
1267 username
[pos
++] = c
;
1274 username
[strcspn(username
, "\n\r")] = '\0';
1277 strncpy(username
, cfg
.username
, 99);
1278 username
[99] = '\0';
1279 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
1280 sprintf(stuff
, "Sent username \"%s\".\r\n", username
);
1281 c_write(stuff
, strlen(stuff
));
1285 send_packet(SSH1_CMSG_USER
, PKT_STR
, username
, PKT_END
);
1287 char userlog
[20+sizeof(username
)];
1288 sprintf(userlog
, "Sent username \"%s\"", username
);
1295 tried_publickey
= 0;
1297 while (pktin
.type
== SSH1_SMSG_FAILURE
) {
1298 static char password
[100];
1299 static char prompt
[200];
1302 static int pwpkt_type
;
1304 * Show password prompt, having first obtained it via a TIS
1305 * or CryptoCard exchange if we're doing TIS or CryptoCard
1308 pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
1309 if (agent_exists()) {
1311 * Attempt RSA authentication using Pageant.
1313 static unsigned char request
[5], *response
, *p
;
1314 static int responselen
;
1315 static int i
, nkeys
;
1316 static int authed
= FALSE
;
1319 logevent("Pageant is running. Requesting keys.");
1321 /* Request the keys held by the agent. */
1322 PUT_32BIT(request
, 1);
1323 request
[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES
;
1324 agent_query(request
, 5, &r
, &responselen
);
1325 response
= (unsigned char *)r
;
1328 nkeys
= GET_32BIT(p
); p
+= 4;
1329 { char buf
[64]; sprintf(buf
, "Pageant has %d keys", nkeys
);
1331 for (i
= 0; i
< nkeys
; i
++) {
1332 static struct RSAKey key
;
1333 static Bignum challenge
;
1334 static char *commentp
;
1335 static int commentlen
;
1337 { char buf
[64]; sprintf(buf
, "Trying Pageant key #%d", i
);
1340 p
+= ssh1_read_bignum(p
, &key
.exponent
);
1341 p
+= ssh1_read_bignum(p
, &key
.modulus
);
1342 commentlen
= GET_32BIT(p
); p
+= 4;
1343 commentp
= p
; p
+= commentlen
;
1344 send_packet(SSH1_CMSG_AUTH_RSA
,
1345 PKT_BIGNUM
, key
.modulus
, PKT_END
);
1347 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1348 logevent("Key refused");
1351 logevent("Received RSA challenge");
1352 ssh1_read_bignum(pktin
.body
, &challenge
);
1354 char *agentreq
, *q
, *ret
;
1356 len
= 1 + 4; /* message type, bit count */
1357 len
+= ssh1_bignum_length(key
.exponent
);
1358 len
+= ssh1_bignum_length(key
.modulus
);
1359 len
+= ssh1_bignum_length(challenge
);
1360 len
+= 16; /* session id */
1361 len
+= 4; /* response format */
1362 agentreq
= malloc(4 + len
);
1363 PUT_32BIT(agentreq
, len
);
1365 *q
++ = SSH_AGENTC_RSA_CHALLENGE
;
1366 PUT_32BIT(q
, ssh1_bignum_bitcount(key
.modulus
));
1368 q
+= ssh1_write_bignum(q
, key
.exponent
);
1369 q
+= ssh1_write_bignum(q
, key
.modulus
);
1370 q
+= ssh1_write_bignum(q
, challenge
);
1371 memcpy(q
, session_id
, 16); q
+= 16;
1372 PUT_32BIT(q
, 1); /* response format */
1373 agent_query(agentreq
, len
+4, &ret
, &retlen
);
1376 if (ret
[4] == SSH_AGENT_RSA_RESPONSE
) {
1377 logevent("Sending Pageant's response");
1378 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1379 PKT_DATA
, ret
+5, 16, PKT_END
);
1382 if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1383 logevent("Pageant's response accepted");
1384 if (flags
& FLAG_VERBOSE
) {
1385 c_write("Authenticated using RSA key \"",
1387 c_write(commentp
, commentlen
);
1388 c_write("\" from agent\r\n", 14);
1392 logevent("Pageant's response not accepted");
1394 logevent("Pageant failed to answer challenge");
1398 logevent("No reply received from Pageant");
1401 freebn(key
.exponent
);
1402 freebn(key
.modulus
);
1411 if (*cfg
.keyfile
&& !tried_publickey
)
1412 pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
1414 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1416 (supported_auths_mask
& (1<<SSH1_AUTH_TIS
))) {
1417 pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
1418 logevent("Requested TIS authentication");
1419 send_packet(SSH1_CMSG_AUTH_TIS
, PKT_END
);
1421 if (pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
1422 logevent("TIS authentication declined");
1423 if (flags
& FLAG_INTERACTIVE
)
1424 c_write("TIS authentication refused.\r\n", 29);
1426 int challengelen
= ((pktin
.body
[0] << 24) |
1427 (pktin
.body
[1] << 16) |
1428 (pktin
.body
[2] << 8) |
1430 logevent("Received TIS challenge");
1431 if (challengelen
> sizeof(prompt
)-1)
1432 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1433 memcpy(prompt
, pktin
.body
+4, challengelen
);
1434 prompt
[challengelen
] = '\0';
1437 if (pktin
.type
== SSH1_SMSG_FAILURE
&&
1439 (supported_auths_mask
& (1<<SSH1_AUTH_CCARD
))) {
1440 pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
1441 logevent("Requested CryptoCard authentication");
1442 send_packet(SSH1_CMSG_AUTH_CCARD
, PKT_END
);
1444 if (pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
1445 logevent("CryptoCard authentication declined");
1446 c_write("CryptoCard authentication refused.\r\n", 29);
1448 int challengelen
= ((pktin
.body
[0] << 24) |
1449 (pktin
.body
[1] << 16) |
1450 (pktin
.body
[2] << 8) |
1452 logevent("Received CryptoCard challenge");
1453 if (challengelen
> sizeof(prompt
)-1)
1454 challengelen
= sizeof(prompt
)-1; /* prevent overrun */
1455 memcpy(prompt
, pktin
.body
+4, challengelen
);
1456 strncpy(prompt
+ challengelen
, "\r\nResponse : ",
1457 sizeof(prompt
)-challengelen
);
1458 prompt
[sizeof(prompt
)-1] = '\0';
1461 if (pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
1462 sprintf(prompt
, "%.90s@%.90s's password: ",
1463 username
, savedhost
);
1465 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1466 char *comment
= NULL
;
1467 if (flags
& FLAG_VERBOSE
)
1468 c_write("Trying public key authentication.\r\n", 35);
1469 if (!rsakey_encrypted(cfg
.keyfile
, &comment
)) {
1470 if (flags
& FLAG_VERBOSE
)
1471 c_write("No passphrase required.\r\n", 25);
1474 sprintf(prompt
, "Passphrase for key \"%.100s\": ", comment
);
1478 if (ssh_get_password
) {
1479 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
1481 * get_password failed to get a password (for
1482 * example because one was supplied on the command
1483 * line which has already failed to work).
1486 logevent("No more passwords to try");
1487 ssh_state
= SSH_STATE_CLOSED
;
1491 c_write(prompt
, strlen(prompt
));
1495 crWaitUntil(!ispkt
);
1496 while (inlen
--) switch (c
= *in
++) {
1513 if (((c
>= ' ' && c
<= '~') ||
1514 ((unsigned char)c
>= 160)) && pos
< sizeof(password
))
1515 password
[pos
++] = c
;
1523 if (pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
1525 * Try public key authentication with the specified
1528 static struct RSAKey pubkey
;
1529 static Bignum challenge
, response
;
1531 static unsigned char buffer
[32];
1533 tried_publickey
= 1;
1534 i
= loadrsakey(cfg
.keyfile
, &pubkey
, NULL
, password
);
1536 c_write("Couldn't load public key from ", 30);
1537 c_write(cfg
.keyfile
, strlen(cfg
.keyfile
));
1538 c_write(".\r\n", 3);
1539 continue; /* go and try password */
1542 c_write("Wrong passphrase.\r\n", 19);
1543 tried_publickey
= 0;
1544 continue; /* try again */
1548 * Send a public key attempt.
1550 send_packet(SSH1_CMSG_AUTH_RSA
,
1551 PKT_BIGNUM
, pubkey
.modulus
, PKT_END
);
1554 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1555 c_write("Server refused our public key.\r\n", 32);
1556 continue; /* go and try password */
1558 if (pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
1559 bombout(("Bizarre response to offer of public key"));
1562 ssh1_read_bignum(pktin
.body
, &challenge
);
1563 response
= rsadecrypt(challenge
, &pubkey
);
1564 freebn(pubkey
.private_exponent
); /* burn the evidence */
1566 for (i
= 0; i
< 32; i
+= 2) {
1567 buffer
[i
] = response
[16-i
/2] >> 8;
1568 buffer
[i
+1] = response
[16-i
/2] & 0xFF;
1572 MD5Update(&md5c
, buffer
, 32);
1573 MD5Update(&md5c
, session_id
, 16);
1574 MD5Final(buffer
, &md5c
);
1576 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE
,
1577 PKT_DATA
, buffer
, 16, PKT_END
);
1580 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1581 if (flags
& FLAG_VERBOSE
)
1582 c_write("Failed to authenticate with our public key.\r\n",
1584 continue; /* go and try password */
1585 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1586 bombout(("Bizarre response to RSA authentication response"));
1590 break; /* we're through! */
1592 send_packet(pwpkt_type
, PKT_STR
, password
, PKT_END
);
1594 logevent("Sent password");
1595 memset(password
, 0, strlen(password
));
1597 if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1598 if (flags
& FLAG_VERBOSE
)
1599 c_write("Access denied\r\n", 15);
1600 logevent("Authentication refused");
1601 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1602 logevent("Received disconnect request");
1603 ssh_state
= SSH_STATE_CLOSED
;
1605 } else if (pktin
.type
!= SSH1_SMSG_SUCCESS
) {
1606 bombout(("Strange packet received, type %d", pktin
.type
));
1611 logevent("Authentication successful");
1616 static void ssh1_protocol(unsigned char *in
, int inlen
, int ispkt
) {
1621 while (!do_ssh1_login(in
, inlen
, ispkt
)) {
1624 if (ssh_state
== SSH_STATE_CLOSED
)
1627 if (cfg
.agentfwd
&& agent_exists()) {
1628 logevent("Requesting agent forwarding");
1629 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
1630 do { crReturnV
; } while (!ispkt
);
1631 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1632 bombout(("Protocol confusion"));
1634 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1635 logevent("Agent forwarding refused");
1637 logevent("Agent forwarding enabled");
1641 send_packet(SSH1_CMSG_REQUEST_PTY
,
1642 PKT_STR
, cfg
.termtype
,
1643 PKT_INT
, rows
, PKT_INT
, cols
,
1644 PKT_INT
, 0, PKT_INT
, 0,
1647 ssh_state
= SSH_STATE_INTERMED
;
1648 do { crReturnV
; } while (!ispkt
);
1649 if (pktin
.type
!= SSH1_SMSG_SUCCESS
&& pktin
.type
!= SSH1_SMSG_FAILURE
) {
1650 bombout(("Protocol confusion"));
1652 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1653 c_write("Server refused to allocate pty\r\n", 32);
1655 logevent("Allocated pty");
1658 if (*cfg
.remote_cmd
)
1659 send_packet(SSH1_CMSG_EXEC_CMD
, PKT_STR
, cfg
.remote_cmd
, PKT_END
);
1661 send_packet(SSH1_CMSG_EXEC_SHELL
, PKT_END
);
1662 logevent("Started session");
1664 ssh_state
= SSH_STATE_SESSION
;
1669 ssh_channels
= newtree234(ssh_channelcmp
);
1674 if (pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
1675 pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
1676 long len
= GET_32BIT(pktin
.body
);
1677 c_writedata(pktin
.body
+4, len
);
1678 } else if (pktin
.type
== SSH1_MSG_DISCONNECT
) {
1679 ssh_state
= SSH_STATE_CLOSED
;
1680 logevent("Received disconnect request");
1681 } else if (pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
1682 /* Remote side is trying to open a channel to talk to our
1683 * agent. Give them back a local channel number. */
1685 struct ssh_channel
*c
;
1687 for (c
= first234(ssh_channels
, &e
); c
; c
= next234(&e
)) {
1689 break; /* found a free number */
1692 c
= malloc(sizeof(struct ssh_channel
));
1693 c
->remoteid
= GET_32BIT(pktin
.body
);
1696 c
->type
= SSH1_SMSG_AGENT_OPEN
; /* identify channel type */
1697 c
->u
.a
.lensofar
= 0;
1698 add234(ssh_channels
, c
);
1699 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
1700 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
1702 } else if (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
1703 pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
1704 /* Remote side closes a channel. */
1705 unsigned i
= GET_32BIT(pktin
.body
);
1706 struct ssh_channel
*c
;
1707 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
1710 closetype
= (pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
1711 send_packet(pktin
.type
, PKT_INT
, c
->remoteid
, PKT_END
);
1712 c
->closes
|= closetype
;
1713 if (c
->closes
== 3) {
1714 del234(ssh_channels
, c
);
1718 } else if (pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
1719 /* Data sent down one of our channels. */
1720 int i
= GET_32BIT(pktin
.body
);
1721 int len
= GET_32BIT(pktin
.body
+4);
1722 unsigned char *p
= pktin
.body
+8;
1723 struct ssh_channel
*c
;
1724 c
= find234(ssh_channels
, &i
, ssh_channelfind
);
1727 case SSH1_SMSG_AGENT_OPEN
:
1728 /* Data for an agent message. Buffer it. */
1730 if (c
->u
.a
.lensofar
< 4) {
1731 int l
= min(4 - c
->u
.a
.lensofar
, len
);
1732 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
, l
);
1733 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
1735 if (c
->u
.a
.lensofar
== 4) {
1736 c
->u
.a
.totallen
= 4 + GET_32BIT(c
->u
.a
.msglen
);
1737 c
->u
.a
.message
= malloc(c
->u
.a
.totallen
);
1738 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
1740 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
1741 int l
= min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
, len
);
1742 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
, l
);
1743 p
+= l
; len
-= l
; c
->u
.a
.lensofar
+= l
;
1745 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
1746 void *reply
, *sentreply
;
1748 agent_query(c
->u
.a
.message
, c
->u
.a
.totallen
,
1753 /* Fake SSH_AGENT_FAILURE. */
1754 sentreply
= "\0\0\0\1\5";
1757 send_packet(SSH1_MSG_CHANNEL_DATA
,
1758 PKT_INT
, c
->remoteid
,
1760 PKT_DATA
, sentreply
, replylen
,
1764 free(c
->u
.a
.message
);
1765 c
->u
.a
.lensofar
= 0;
1771 } else if (pktin
.type
== SSH1_SMSG_SUCCESS
) {
1772 /* may be from EXEC_SHELL on some servers */
1773 } else if (pktin
.type
== SSH1_SMSG_FAILURE
) {
1774 /* may be from EXEC_SHELL on some servers
1775 * if no pty is available or in other odd cases. Ignore */
1776 } else if (pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
1777 send_packet(SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
1779 bombout(("Strange packet received: type %d", pktin
.type
));
1783 send_packet(SSH1_CMSG_STDIN_DATA
,
1784 PKT_INT
, inlen
, PKT_DATA
, in
, inlen
, PKT_END
);
1792 * Utility routine for decoding comma-separated strings in KEXINIT.
1794 static int in_commasep_string(char *needle
, char *haystack
, int haylen
) {
1795 int needlen
= strlen(needle
);
1798 * Is it at the start of the string?
1800 if (haylen
>= needlen
&& /* haystack is long enough */
1801 !memcmp(needle
, haystack
, needlen
) && /* initial match */
1802 (haylen
== needlen
|| haystack
[needlen
] == ',')
1803 /* either , or EOS follows */
1807 * If not, search for the next comma and resume after that.
1808 * If no comma found, terminate.
1810 while (haylen
> 0 && *haystack
!= ',')
1811 haylen
--, haystack
++;
1814 haylen
--, haystack
++; /* skip over comma itself */
1819 * SSH2 key creation method.
1821 static void ssh2_mkkey(Bignum K
, char *H
, char chr
, char *keyspace
) {
1823 /* First 20 bytes. */
1826 SHA_Bytes(&s
, H
, 20);
1827 SHA_Bytes(&s
, &chr
, 1);
1828 SHA_Bytes(&s
, H
, 20);
1829 SHA_Final(&s
, keyspace
);
1830 /* Next 20 bytes. */
1833 SHA_Bytes(&s
, H
, 20);
1834 SHA_Bytes(&s
, keyspace
, 20);
1835 SHA_Final(&s
, keyspace
+20);
1839 * Handle the SSH2 transport layer.
1841 static int do_ssh2_transport(unsigned char *in
, int inlen
, int ispkt
)
1845 static Bignum e
, f
, K
;
1846 static const struct ssh_mac
**maclist
;
1848 static const struct ssh_cipher
*cscipher_tobe
= NULL
;
1849 static const struct ssh_cipher
*sccipher_tobe
= NULL
;
1850 static const struct ssh_mac
*csmac_tobe
= NULL
;
1851 static const struct ssh_mac
*scmac_tobe
= NULL
;
1852 static const struct ssh_compress
*cscomp_tobe
= NULL
;
1853 static const struct ssh_compress
*sccomp_tobe
= NULL
;
1854 static char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
1855 static int hostkeylen
, siglen
;
1856 static unsigned char exchange_hash
[20];
1857 static unsigned char keyspace
[40];
1858 static const struct ssh_cipher
*preferred_cipher
;
1864 * Set up the preferred cipher.
1866 if (cfg
.cipher
== CIPHER_BLOWFISH
) {
1867 preferred_cipher
= &ssh_blowfish_ssh2
;
1868 } else if (cfg
.cipher
== CIPHER_DES
) {
1869 logevent("Single DES not supported in SSH2; using 3DES");
1870 preferred_cipher
= &ssh_3des_ssh2
;
1871 } else if (cfg
.cipher
== CIPHER_3DES
) {
1872 preferred_cipher
= &ssh_3des_ssh2
;
1874 /* Shouldn't happen, but we do want to initialise to _something_. */
1875 preferred_cipher
= &ssh_3des_ssh2
;
1879 * Be prepared to work around the buggy MAC problem.
1882 maclist
= buggymacs
, nmacs
= lenof(buggymacs
);
1884 maclist
= macs
, nmacs
= lenof(macs
);
1888 * Construct and send our key exchange packet.
1890 ssh2_pkt_init(SSH2_MSG_KEXINIT
);
1891 for (i
= 0; i
< 16; i
++)
1892 ssh2_pkt_addbyte((unsigned char)random_byte());
1893 /* List key exchange algorithms. */
1894 ssh2_pkt_addstring_start();
1895 for (i
= 0; i
< lenof(kex_algs
); i
++) {
1896 ssh2_pkt_addstring_str(kex_algs
[i
]->name
);
1897 if (i
< lenof(kex_algs
)-1)
1898 ssh2_pkt_addstring_str(",");
1900 /* List server host key algorithms. */
1901 ssh2_pkt_addstring_start();
1902 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
1903 ssh2_pkt_addstring_str(hostkey_algs
[i
]->name
);
1904 if (i
< lenof(hostkey_algs
)-1)
1905 ssh2_pkt_addstring_str(",");
1907 /* List client->server encryption algorithms. */
1908 ssh2_pkt_addstring_start();
1909 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
1910 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
1911 ssh2_pkt_addstring_str(c
->name
);
1912 if (i
< lenof(ciphers
))
1913 ssh2_pkt_addstring_str(",");
1915 /* List server->client encryption algorithms. */
1916 ssh2_pkt_addstring_start();
1917 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
1918 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
1919 ssh2_pkt_addstring_str(c
->name
);
1920 if (i
< lenof(ciphers
))
1921 ssh2_pkt_addstring_str(",");
1923 /* List client->server MAC algorithms. */
1924 ssh2_pkt_addstring_start();
1925 for (i
= 0; i
< nmacs
; i
++) {
1926 ssh2_pkt_addstring_str(maclist
[i
]->name
);
1928 ssh2_pkt_addstring_str(",");
1930 /* List server->client MAC algorithms. */
1931 ssh2_pkt_addstring_start();
1932 for (i
= 0; i
< nmacs
; i
++) {
1933 ssh2_pkt_addstring_str(maclist
[i
]->name
);
1935 ssh2_pkt_addstring_str(",");
1937 /* List client->server compression algorithms. */
1938 ssh2_pkt_addstring_start();
1939 for (i
= 0; i
< lenof(compressions
); i
++) {
1940 ssh2_pkt_addstring_str(compressions
[i
]->name
);
1941 if (i
< lenof(compressions
)-1)
1942 ssh2_pkt_addstring_str(",");
1944 /* List server->client compression algorithms. */
1945 ssh2_pkt_addstring_start();
1946 for (i
= 0; i
< lenof(compressions
); i
++) {
1947 ssh2_pkt_addstring_str(compressions
[i
]->name
);
1948 if (i
< lenof(compressions
)-1)
1949 ssh2_pkt_addstring_str(",");
1951 /* List client->server languages. Empty list. */
1952 ssh2_pkt_addstring_start();
1953 /* List server->client languages. Empty list. */
1954 ssh2_pkt_addstring_start();
1955 /* First KEX packet does _not_ follow, because we're not that brave. */
1956 ssh2_pkt_addbool(FALSE
);
1958 ssh2_pkt_adduint32(0);
1959 sha_string(&exhash
, pktout
.data
+5, pktout
.length
-5);
1962 if (!ispkt
) crWaitUntil(ispkt
);
1963 sha_string(&exhash
, pktin
.data
+5, pktin
.length
-5);
1966 * Now examine the other side's KEXINIT to see what we're up
1969 if (pktin
.type
!= SSH2_MSG_KEXINIT
) {
1970 bombout(("expected key exchange packet from server"));
1973 kex
= NULL
; hostkey
= NULL
; cscipher_tobe
= NULL
; sccipher_tobe
= NULL
;
1974 csmac_tobe
= NULL
; scmac_tobe
= NULL
; cscomp_tobe
= NULL
; sccomp_tobe
= NULL
;
1975 pktin
.savedpos
+= 16; /* skip garbage cookie */
1976 ssh2_pkt_getstring(&str
, &len
); /* key exchange algorithms */
1977 for (i
= 0; i
< lenof(kex_algs
); i
++) {
1978 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
1983 ssh2_pkt_getstring(&str
, &len
); /* host key algorithms */
1984 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
1985 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
1986 hostkey
= hostkey_algs
[i
];
1990 ssh2_pkt_getstring(&str
, &len
); /* client->server cipher */
1991 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
1992 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
1993 if (in_commasep_string(c
->name
, str
, len
)) {
1998 ssh2_pkt_getstring(&str
, &len
); /* server->client cipher */
1999 for (i
= 0; i
< lenof(ciphers
)+1; i
++) {
2000 const struct ssh_cipher
*c
= i
==0 ? preferred_cipher
: ciphers
[i
-1];
2001 if (in_commasep_string(c
->name
, str
, len
)) {
2006 ssh2_pkt_getstring(&str
, &len
); /* client->server mac */
2007 for (i
= 0; i
< nmacs
; i
++) {
2008 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2009 csmac_tobe
= maclist
[i
];
2013 ssh2_pkt_getstring(&str
, &len
); /* server->client mac */
2014 for (i
= 0; i
< nmacs
; i
++) {
2015 if (in_commasep_string(maclist
[i
]->name
, str
, len
)) {
2016 scmac_tobe
= maclist
[i
];
2020 ssh2_pkt_getstring(&str
, &len
); /* client->server compression */
2021 for (i
= 0; i
< lenof(compressions
); i
++) {
2022 if (in_commasep_string(compressions
[i
]->name
, str
, len
)) {
2023 cscomp_tobe
= compressions
[i
];
2027 ssh2_pkt_getstring(&str
, &len
); /* server->client compression */
2028 for (i
= 0; i
< lenof(compressions
); i
++) {
2029 if (in_commasep_string(compressions
[i
]->name
, str
, len
)) {
2030 sccomp_tobe
= compressions
[i
];
2036 * Currently we only support Diffie-Hellman and DSS, so let's
2037 * bomb out if those aren't selected.
2039 if (kex
!= &ssh_diffiehellman
|| hostkey
!= &ssh_dss
) {
2040 bombout(("internal fault: chaos in SSH 2 transport layer"));
2045 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2048 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT
);
2053 if (pktin
.type
!= SSH2_MSG_KEXDH_REPLY
) {
2054 bombout(("expected key exchange packet from server"));
2057 ssh2_pkt_getstring(&hostkeydata
, &hostkeylen
);
2058 f
= ssh2_pkt_getmp();
2059 ssh2_pkt_getstring(&sigdata
, &siglen
);
2063 sha_string(&exhash
, hostkeydata
, hostkeylen
);
2064 sha_mpint(&exhash
, e
);
2065 sha_mpint(&exhash
, f
);
2066 sha_mpint(&exhash
, K
);
2067 SHA_Final(&exhash
, exchange_hash
);
2070 debug(("Exchange hash is:\r\n"));
2071 for (i
= 0; i
< 20; i
++)
2072 debug((" %02x", exchange_hash
[i
]));
2076 hostkey
->setkey(hostkeydata
, hostkeylen
);
2077 if (!hostkey
->verifysig(sigdata
, siglen
, exchange_hash
, 20)) {
2078 bombout(("Server failed host key check"));
2083 * Expect SSH2_MSG_NEWKEYS from server.
2086 if (pktin
.type
!= SSH2_MSG_NEWKEYS
) {
2087 bombout(("expected new-keys packet from server"));
2092 * Authenticate remote host: verify host key. (We've already
2093 * checked the signature of the exchange hash.)
2095 keystr
= hostkey
->fmtkey();
2096 fingerprint
= hostkey
->fingerprint();
2097 verify_ssh_host_key(savedhost
, savedport
, hostkey
->keytype
,
2098 keystr
, fingerprint
);
2099 logevent("Host key fingerprint is:");
2100 logevent(fingerprint
);
2105 * Send SSH2_MSG_NEWKEYS.
2107 ssh2_pkt_init(SSH2_MSG_NEWKEYS
);
2111 * Create and initialise session keys.
2113 cscipher
= cscipher_tobe
;
2114 sccipher
= sccipher_tobe
;
2117 cscomp
= cscomp_tobe
;
2118 sccomp
= sccomp_tobe
;
2120 * Set IVs after keys.
2122 ssh2_mkkey(K
, exchange_hash
, 'C', keyspace
); cscipher
->setcskey(keyspace
);
2123 ssh2_mkkey(K
, exchange_hash
, 'D', keyspace
); cscipher
->setsckey(keyspace
);
2124 ssh2_mkkey(K
, exchange_hash
, 'A', keyspace
); cscipher
->setcsiv(keyspace
);
2125 ssh2_mkkey(K
, exchange_hash
, 'B', keyspace
); sccipher
->setsciv(keyspace
);
2126 ssh2_mkkey(K
, exchange_hash
, 'E', keyspace
); csmac
->setcskey(keyspace
);
2127 ssh2_mkkey(K
, exchange_hash
, 'F', keyspace
); scmac
->setsckey(keyspace
);
2130 * Now we're encrypting. Begin returning 1 to the protocol main
2131 * function so that other things can run on top of the
2132 * transport. If we ever see a KEXINIT, we must go back to the
2137 } while (!(ispkt
&& pktin
.type
== SSH2_MSG_KEXINIT
));
2138 goto begin_key_exchange
;
2144 * Handle the SSH2 userauth and connection layers.
2146 static void do_ssh2_authconn(unsigned char *in
, int inlen
, int ispkt
)
2148 static unsigned long remote_winsize
;
2149 static unsigned long remote_maxpkt
;
2154 * Request userauth protocol, and await a response to it.
2156 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST
);
2157 ssh2_pkt_addstring("ssh-userauth");
2159 crWaitUntilV(ispkt
);
2160 if (pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
2161 bombout(("Server refused user authentication protocol"));
2166 * FIXME: currently we support only password authentication.
2167 * (This places us technically in violation of the SSH2 spec.
2168 * We must fix this.)
2172 * Get a username and a password.
2174 static char username
[100];
2175 static char password
[100];
2179 if ((flags
& FLAG_INTERACTIVE
) && !*cfg
.username
) {
2180 c_write("login as: ", 10);
2183 crWaitUntilV(!ispkt
);
2184 while (inlen
--) switch (c
= *in
++) {
2191 c_write("\b \b", 3);
2197 c_write("\b \b", 3);
2206 if (((c
>= ' ' && c
<= '~') ||
2207 ((unsigned char)c
>= 160)) && pos
< 40) {
2208 username
[pos
++] = c
;
2215 username
[strcspn(username
, "\n\r")] = '\0';
2218 strncpy(username
, cfg
.username
, 99);
2219 username
[99] = '\0';
2220 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
2221 sprintf(stuff
, "Using username \"%s\".\r\n", username
);
2222 c_write(stuff
, strlen(stuff
));
2226 if (ssh_get_password
) {
2228 sprintf(prompt
, "%.90s@%.90s's password: ", username
, savedhost
);
2229 if (!ssh_get_password(prompt
, password
, sizeof(password
))) {
2231 * get_password failed to get a password (for
2232 * example because one was supplied on the command
2233 * line which has already failed to work).
2236 logevent("No more passwords to try");
2237 ssh_state
= SSH_STATE_CLOSED
;
2241 c_write("password: ", 10);
2246 crWaitUntilV(!ispkt
);
2247 while (inlen
--) switch (c
= *in
++) {
2264 if (((c
>= ' ' && c
<= '~') ||
2265 ((unsigned char)c
>= 160)) && pos
< 40)
2266 password
[pos
++] = c
;
2273 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST
);
2274 ssh2_pkt_addstring(username
);
2275 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2276 ssh2_pkt_addstring("password");
2277 ssh2_pkt_addbool(FALSE
);
2278 ssh2_pkt_addstring(password
);
2281 crWaitUntilV(ispkt
);
2282 if (pktin
.type
!= SSH2_MSG_USERAUTH_SUCCESS
) {
2283 c_write("Access denied\r\n", 15);
2284 logevent("Authentication refused");
2290 * Now we're authenticated for the connection protocol. The
2291 * connection protocol will automatically have started at this
2292 * point; there's no need to send SERVICE_REQUEST.
2296 * So now create a channel with a session in it.
2298 mainchan
= malloc(sizeof(struct ssh_channel
));
2299 mainchan
->localid
= 100; /* as good as any */
2300 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN
);
2301 ssh2_pkt_addstring("session");
2302 ssh2_pkt_adduint32(mainchan
->localid
);
2303 ssh2_pkt_adduint32(0x8000UL
); /* our window size */
2304 ssh2_pkt_adduint32(0x4000UL
); /* our max pkt size */
2306 crWaitUntilV(ispkt
);
2307 if (pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
2308 bombout(("Server refused to open a session"));
2310 /* FIXME: error data comes back in FAILURE packet */
2312 if (ssh2_pkt_getuint32() != mainchan
->localid
) {
2313 bombout(("Server's channel confirmation cited wrong channel"));
2316 mainchan
->remoteid
= ssh2_pkt_getuint32();
2317 mainchan
->u
.v2
.remwindow
= ssh2_pkt_getuint32();
2318 mainchan
->u
.v2
.remmaxpkt
= ssh2_pkt_getuint32();
2319 mainchan
->u
.v2
.outbuffer
= NULL
;
2320 mainchan
->u
.v2
.outbuflen
= mainchan
->u
.v2
.outbufsize
= 0;
2321 logevent("Opened channel for session");
2324 * Now allocate a pty for the session.
2327 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2328 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2329 ssh2_pkt_addstring("pty-req");
2330 ssh2_pkt_addbool(1); /* want reply */
2331 ssh2_pkt_addstring(cfg
.termtype
);
2332 ssh2_pkt_adduint32(cols
);
2333 ssh2_pkt_adduint32(rows
);
2334 ssh2_pkt_adduint32(0); /* pixel width */
2335 ssh2_pkt_adduint32(0); /* pixel height */
2336 ssh2_pkt_addstring_start();
2337 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2341 crWaitUntilV(ispkt
);
2342 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2343 /* FIXME: be able to handle other channels here */
2344 if (ssh2_pkt_getuint32() != mainchan
->localid
)
2345 continue; /* wrong channel */
2346 mainchan
->u
.v2
.remwindow
+= ssh2_pkt_getuint32();
2348 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2350 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2351 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2352 bombout(("Server got confused by pty request"));
2355 c_write("Server refused to allocate pty\r\n", 32);
2357 logevent("Allocated pty");
2362 * Start a shell or a remote command.
2364 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST
);
2365 ssh2_pkt_adduint32(mainchan
->remoteid
); /* recipient channel */
2366 if (*cfg
.remote_cmd
) {
2367 ssh2_pkt_addstring("exec");
2368 ssh2_pkt_addbool(1); /* want reply */
2369 ssh2_pkt_addstring(cfg
.remote_cmd
);
2371 ssh2_pkt_addstring("shell");
2372 ssh2_pkt_addbool(1); /* want reply */
2376 crWaitUntilV(ispkt
);
2377 if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2378 /* FIXME: be able to handle other channels here */
2379 if (ssh2_pkt_getuint32() != mainchan
->localid
)
2380 continue; /* wrong channel */
2381 mainchan
->u
.v2
.remwindow
+= ssh2_pkt_getuint32();
2383 } while (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2384 if (pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
2385 if (pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
2386 bombout(("Server got confused by shell/command request"));
2389 bombout(("Server refused to start a shell/command"));
2392 logevent("Started a shell/command");
2401 static int try_send
;
2405 if (pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
2406 pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
2409 /* FIXME: be able to handle other channels here */
2410 if (ssh2_pkt_getuint32() != mainchan
->localid
)
2411 continue; /* wrong channel */
2412 if (pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
2413 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR
)
2414 continue; /* extended but not stderr */
2415 ssh2_pkt_getstring(&data
, &length
);
2417 c_writedata(data
, length
);
2419 * Enlarge the window again at the remote side,
2420 * just in case it ever runs down and they fail
2421 * to send us any more data.
2423 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
2424 ssh2_pkt_adduint32(mainchan
->remoteid
);
2425 ssh2_pkt_adduint32(length
);
2428 } else if (pktin
.type
== SSH2_MSG_DISCONNECT
) {
2429 ssh_state
= SSH_STATE_CLOSED
;
2430 logevent("Received disconnect message");
2431 } else if (pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
2432 continue; /* exit status et al; ignore (FIXME?) */
2433 } else if (pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
2434 continue; /* remote sends EOF; ignore */
2435 } else if (pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
2436 /* FIXME: be able to handle other channels here */
2437 if (ssh2_pkt_getuint32() != mainchan
->localid
)
2438 continue; /* wrong channel */
2439 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE
);
2440 ssh2_pkt_adduint32(mainchan
->remoteid
);
2442 /* FIXME: mark the channel as closed */
2443 if (1 /* FIXME: "all channels are closed" */) {
2444 logevent("All channels closed. Disconnecting");
2445 ssh2_pkt_init(SSH2_MSG_DISCONNECT
);
2447 ssh_state
= SSH_STATE_CLOSED
;
2451 continue; /* remote sends close; ignore (FIXME) */
2452 } else if (pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
2453 /* FIXME: be able to handle other channels here */
2454 if (ssh2_pkt_getuint32() != mainchan
->localid
)
2455 continue; /* wrong channel */
2456 mainchan
->u
.v2
.remwindow
+= ssh2_pkt_getuint32();
2459 bombout(("Strange packet received: type %d", pktin
.type
));
2464 * We have spare data. Add it to the channel buffer.
2466 if (mainchan
->u
.v2
.outbufsize
<
2467 mainchan
->u
.v2
.outbuflen
+ inlen
) {
2468 mainchan
->u
.v2
.outbufsize
=
2469 mainchan
->u
.v2
.outbuflen
+ inlen
+ 1024;
2470 mainchan
->u
.v2
.outbuffer
= srealloc(mainchan
->u
.v2
.outbuffer
,
2471 mainchan
->u
.v2
.outbufsize
);
2473 memcpy(mainchan
->u
.v2
.outbuffer
+ mainchan
->u
.v2
.outbuflen
,
2475 mainchan
->u
.v2
.outbuflen
+= inlen
;
2480 * Try to send data on the channel if we can. (FIXME:
2481 * on _all_ channels.)
2483 while (mainchan
->u
.v2
.remwindow
> 0 &&
2484 mainchan
->u
.v2
.outbuflen
> 0) {
2485 unsigned len
= mainchan
->u
.v2
.remwindow
;
2486 if (len
> mainchan
->u
.v2
.outbuflen
)
2487 len
= mainchan
->u
.v2
.outbuflen
;
2488 if (len
> mainchan
->u
.v2
.remmaxpkt
)
2489 len
= mainchan
->u
.v2
.remmaxpkt
;
2490 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA
);
2491 ssh2_pkt_adduint32(mainchan
->remoteid
);
2492 ssh2_pkt_addstring_start();
2493 ssh2_pkt_addstring_data(mainchan
->u
.v2
.outbuffer
, len
);
2495 mainchan
->u
.v2
.outbuflen
-= len
;
2496 memmove(mainchan
->u
.v2
.outbuffer
, mainchan
->u
.v2
.outbuffer
+len
,
2497 mainchan
->u
.v2
.outbuflen
);
2498 mainchan
->u
.v2
.remwindow
-= len
;
2507 * Handle the top-level SSH2 protocol.
2509 static void ssh2_protocol(unsigned char *in
, int inlen
, int ispkt
)
2511 if (do_ssh2_transport(in
, inlen
, ispkt
) == 0)
2513 do_ssh2_authconn(in
, inlen
, ispkt
);
2517 * Called to set up the connection. Will arrange for WM_NETEVENT
2518 * messages to be passed to the specified window, whose window
2519 * procedure should then call telnet_msg().
2521 * Returns an error message, or NULL on success.
2523 static char *ssh_init (HWND hwnd
, char *host
, int port
, char **realhost
) {
2527 if(crypto_startup() == 0)
2528 return "Microsoft high encryption pack not installed!";
2531 p
= connect_to_host(host
, port
, realhost
);
2536 return "Protocol initialisation error";
2538 if (hwnd
&& WSAAsyncSelect (s
, hwnd
, WM_NETEVENT
, FD_READ
| FD_CLOSE
) == SOCKET_ERROR
)
2539 switch (WSAGetLastError()) {
2540 case WSAENETDOWN
: return "Network is down";
2541 default: return "WSAAsyncSelect(): unknown error";
2548 * Process a WM_NETEVENT message. Will return 0 if the connection
2549 * has closed, or <0 for a socket error.
2551 static int ssh_msg (WPARAM wParam
, LPARAM lParam
) {
2556 * Because reading less than the whole of the available pending
2557 * data can generate an FD_READ event, we need to allow for the
2558 * possibility that FD_READ may arrive with FD_CLOSE already in
2559 * the queue; so it's possible that we can get here even with s
2560 * invalid. If so, we return 1 and don't worry about it.
2562 if (s
== INVALID_SOCKET
)
2565 if (WSAGETSELECTERROR(lParam
) != 0) {
2568 return -WSAGETSELECTERROR(lParam
);
2571 switch (WSAGETSELECTEVENT(lParam
)) {
2574 ret
= recv(s
, buf
, sizeof(buf
), 0);
2575 if (ret
< 0 && WSAGetLastError() == WSAEWOULDBLOCK
)
2577 if (ret
< 0) { /* any _other_ error */
2580 return -10000-WSAGetLastError();
2586 ssh_gotdata (buf
, ret
);
2587 if (ssh_state
== SSH_STATE_CLOSED
) {
2594 return 1; /* shouldn't happen, but WTF */
2598 * Called to send data down the Telnet connection.
2600 static void ssh_send (char *buf
, int len
) {
2601 if (s
== INVALID_SOCKET
)
2604 ssh_protocol(buf
, len
, 0);
2608 * Called to set the size of the window from Telnet's POV.
2610 static void ssh_size(void) {
2611 switch (ssh_state
) {
2612 case SSH_STATE_BEFORE_SIZE
:
2613 case SSH_STATE_CLOSED
:
2614 break; /* do nothing */
2615 case SSH_STATE_INTERMED
:
2616 size_needed
= TRUE
; /* buffer for later */
2618 case SSH_STATE_SESSION
:
2620 send_packet(SSH1_CMSG_WINDOW_SIZE
,
2621 PKT_INT
, rows
, PKT_INT
, cols
,
2622 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
2628 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2629 * can send an EOF and collect resulting output (e.g. `plink
2632 static void ssh_special (Telnet_Special code
) {
2633 if (code
== TS_EOF
) {
2634 if (ssh_version
== 1) {
2635 send_packet(SSH1_CMSG_EOF
, PKT_END
);
2637 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF
);
2638 ssh2_pkt_adduint32(mainchan
->remoteid
);
2641 logevent("Sent EOF message");
2642 } else if (code
== TS_PING
) {
2643 if (ssh_version
== 1) {
2644 send_packet(SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
2646 ssh2_pkt_init(SSH2_MSG_IGNORE
);
2647 ssh2_pkt_addstring_start();
2655 static SOCKET
ssh_socket(void) { return s
; }
2657 static int ssh_sendok(void) { return ssh_send_ok
; }
2659 Backend ssh_backend
= {