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, 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 = {