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_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[] = { &ssh_sha1, &ssh_mac_none };
179 const static struct ssh_mac *buggymacs[] = { &ssh_sha1_buggy, &ssh_mac_none };
181 const static struct ssh_compress ssh_comp_none = {
184 const static struct ssh_compress *compressions[] = { &ssh_comp_none };
187 * 2-3-4 tree storing channels.
190 unsigned remoteid, localid;
194 struct ssh_agent_channel {
195 unsigned char *message;
196 unsigned char msglen[4];
197 int lensofar, totallen;
199 struct ssh2_data_channel {
200 unsigned char *outbuffer;
201 unsigned outbuflen, outbufsize;
202 unsigned remwindow, remmaxpkt;
216 static SHA_State exhash;
218 static SOCKET s = INVALID_SOCKET;
220 static unsigned char session_key[32];
221 static const struct ssh_cipher *cipher = NULL;
222 static const struct ssh_cipher *cscipher = NULL;
223 static const struct ssh_cipher *sccipher = NULL;
224 static const struct ssh_mac *csmac = NULL;
225 static const struct ssh_mac *scmac = NULL;
226 static const struct ssh_compress *cscomp = NULL;
227 static const struct ssh_compress *sccomp = NULL;
228 static const struct ssh_kex *kex = NULL;
229 static const struct ssh_hostkey *hostkey = NULL;
230 int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
232 static char *savedhost;
233 static int savedport;
234 static int ssh_send_ok;
236 static tree234 *ssh_channels; /* indexed by local id */
237 static struct ssh_channel *mainchan; /* primary session channel */
240 SSH_STATE_BEFORE_SIZE,
244 } ssh_state = SSH_STATE_BEFORE_SIZE;
246 static int size_needed = FALSE;
248 static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
249 static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
251 static int ssh_version;
252 static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
253 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
254 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
255 static void ssh_size(void);
257 static int (*s_rdpkt)(unsigned char **data, int *datalen);
259 static struct rdpkt1_state_tag {
260 long len, pad, biglen, to_read;
261 unsigned long realcrc, gotcrc;
267 static struct rdpkt2_state_tag {
268 long len, pad, payload, packetlen, maclen;
271 unsigned long incoming_sequence;
274 static int ssh_channelcmp(void *av, void *bv) {
275 struct ssh_channel *a = (struct ssh_channel *)av;
276 struct ssh_channel *b = (struct ssh_channel *)bv;
277 if (a->localid < b->localid) return -1;
278 if (a->localid > b->localid) return +1;
281 static int ssh_channelfind(void *av, void *bv) {
282 unsigned *a = (unsigned *)av;
283 struct ssh_channel *b = (struct ssh_channel *)bv;
284 if (*a < b->localid) return -1;
285 if (*a > b->localid) return +1;
289 static void s_write (char *buf, int len) {
291 int i = send (s, buf, len, 0);
294 bombout(("Lost connection while sending"));
302 static int s_read (char *buf, int len) {
305 int i = recv (s, buf, len, 0);
308 len -= i, buf += i, ret += i;
315 static void c_write (char *buf, int len) {
316 if ((flags & FLAG_STDERR)) {
318 for (i = 0; i < len; i++)
320 fputc(buf[i], stderr);
327 static void c_writedata (char *buf, int len) {
333 * Collect incoming data in the incoming packet buffer.
334 * Decipher and verify the packet when it is completely read.
335 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
336 * Update the *data and *datalen variables.
337 * Return the additional nr of bytes needed, or 0 when
338 * a complete packet is available.
340 static int ssh1_rdpkt(unsigned char **data, int *datalen)
342 struct rdpkt1_state_tag *st = &rdpkt1_state;
351 for (st->i = st->len = 0; st->i < 4; st->i++) {
352 while ((*datalen) == 0)
354 st->len = (st->len << 8) + **data;
355 (*data)++, (*datalen)--;
359 if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */
360 st->len = 0x300; /* big enough to carry to end */
364 st->pad = 8 - (st->len % 8);
365 st->biglen = st->len + st->pad;
366 pktin.length = st->len - 5;
368 if (pktin.maxlen < st->biglen) {
369 pktin.maxlen = st->biglen;
370 pktin.data = (pktin.data == NULL ? malloc(st->biglen+APIEXTRA) :
371 realloc(pktin.data, st->biglen+APIEXTRA));
373 fatalbox("Out of memory");
376 st->to_read = st->biglen;
378 while (st->to_read > 0) {
379 st->chunk = st->to_read;
380 while ((*datalen) == 0)
381 crReturn(st->to_read);
382 if (st->chunk > (*datalen))
383 st->chunk = (*datalen);
384 memcpy(st->p, *data, st->chunk);
386 *datalen -= st->chunk;
388 st->to_read -= st->chunk;
392 cipher->decrypt(pktin.data, st->biglen);
394 pktin.type = pktin.data[st->pad];
395 pktin.body = pktin.data + st->pad + 1;
397 st->realcrc = crc32(pktin.data, st->biglen-4);
398 st->gotcrc = GET_32BIT(pktin.data+st->biglen-4);
399 if (st->gotcrc != st->realcrc) {
400 bombout(("Incorrect CRC received on packet"));
404 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
405 pktin.type == SSH1_SMSG_STDERR_DATA ||
406 pktin.type == SSH1_MSG_DEBUG ||
407 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
408 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
409 long strlen = GET_32BIT(pktin.body);
410 if (strlen + 4 != pktin.length) {
411 bombout(("Received data packet with bogus string length"));
416 if (pktin.type == SSH1_MSG_DEBUG) {
417 /* log debug message */
419 int strlen = GET_32BIT(pktin.body);
420 strcpy(buf, "Remote: ");
421 if (strlen > 70) strlen = 70;
422 memcpy(buf+8, pktin.body+4, strlen);
423 buf[8+strlen] = '\0';
426 } else if (pktin.type == SSH1_MSG_IGNORE) {
434 static int ssh2_rdpkt(unsigned char **data, int *datalen)
436 struct rdpkt2_state_tag *st = &rdpkt2_state;
444 st->cipherblk = sccipher->blksize;
447 if (st->cipherblk < 8)
450 if (pktin.maxlen < st->cipherblk) {
451 pktin.maxlen = st->cipherblk;
452 pktin.data = (pktin.data == NULL ? malloc(st->cipherblk+APIEXTRA) :
453 realloc(pktin.data, st->cipherblk+APIEXTRA));
455 fatalbox("Out of memory");
459 * Acquire and decrypt the first block of the packet. This will
460 * contain the length and padding details.
462 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
463 while ((*datalen) == 0)
464 crReturn(st->cipherblk-st->i);
465 pktin.data[st->i] = *(*data)++;
469 if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
474 sccipher->decrypt(pktin.data, st->cipherblk);
477 * Now get the length and padding figures.
479 st->len = GET_32BIT(pktin.data);
480 st->pad = pktin.data[4];
483 * This enables us to deduce the payload length.
485 st->payload = st->len - st->pad - 1;
487 pktin.length = st->payload + 5;
490 * So now we can work out the total packet length.
492 st->packetlen = st->len + 4;
493 st->maclen = scmac ? scmac->len : 0;
496 * Adjust memory allocation if packet is too big.
498 if (pktin.maxlen < st->packetlen+st->maclen) {
499 pktin.maxlen = st->packetlen+st->maclen;
500 pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
501 realloc(pktin.data, pktin.maxlen+APIEXTRA));
503 fatalbox("Out of memory");
507 * Read and decrypt the remainder of the packet.
509 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) {
510 while ((*datalen) == 0)
511 crReturn(st->packetlen + st->maclen - st->i);
512 pktin.data[st->i] = *(*data)++;
515 /* Decrypt everything _except_ the MAC. */
517 sccipher->decrypt(pktin.data + st->cipherblk,
518 st->packetlen - st->cipherblk);
521 debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
522 for (st->i = 0; st->i < st->packetlen; st->i++)
523 debug((" %02x", (unsigned char)pktin.data[st->i]));
530 if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) {
531 bombout(("Incorrect MAC received on packet"));
534 st->incoming_sequence++; /* whether or not we MACed */
537 pktin.type = pktin.data[5];
539 if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
540 goto next_packet; /* FIXME: print DEBUG message */
545 static void ssh_gotdata(unsigned char *data, int datalen)
547 while (datalen > 0) {
548 if ( s_rdpkt(&data, &datalen) == 0 ) {
549 ssh_protocol(NULL, 0, 1);
550 if (ssh_state == SSH_STATE_CLOSED) {
558 static void s_wrpkt_start(int type, int len) {
561 len += 5; /* type and CRC */
565 pktout.length = len-5;
566 if (pktout.maxlen < biglen) {
567 pktout.maxlen = biglen;
569 /* Allocate enough buffer space for extra block
570 * for MS CryptEncrypt() */
571 pktout.data = (pktout.data == NULL ? malloc(biglen+12) :
572 realloc(pktout.data, biglen+12));
574 pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
575 realloc(pktout.data, biglen+4));
578 fatalbox("Out of memory");
582 pktout.body = pktout.data+4+pad+1;
585 static void s_wrpkt(void) {
586 int pad, len, biglen, i;
589 len = pktout.length + 5; /* type and CRC */
593 pktout.body[-1] = pktout.type;
594 for (i=0; i<pad; i++)
595 pktout.data[i+4] = random_byte();
596 crc = crc32(pktout.data+4, biglen-4);
597 PUT_32BIT(pktout.data+biglen, crc);
598 PUT_32BIT(pktout.data, len);
601 cipher->encrypt(pktout.data+4, biglen);
603 s_write(pktout.data, biglen+4);
607 * Construct a packet with the specified contents and
608 * send it to the server.
610 static void send_packet(int pkttype, ...)
613 unsigned char *p, *argp, argchar;
614 unsigned long argint;
615 int pktlen, argtype, arglen;
619 va_start(args, pkttype);
620 while ((argtype = va_arg(args, int)) != PKT_END) {
623 (void) va_arg(args, int);
627 (void) va_arg(args, char);
631 (void) va_arg(args, unsigned char *);
632 arglen = va_arg(args, int);
636 argp = va_arg(args, unsigned char *);
637 arglen = strlen(argp);
638 pktlen += 4 + arglen;
641 bn = va_arg(args, Bignum);
642 pktlen += ssh1_bignum_length(bn);
650 s_wrpkt_start(pkttype, pktlen);
653 va_start(args, pkttype);
654 while ((argtype = va_arg(args, int)) != PKT_END) {
657 argint = va_arg(args, int);
658 PUT_32BIT(p, argint);
662 argchar = va_arg(args, unsigned char);
667 argp = va_arg(args, unsigned char *);
668 arglen = va_arg(args, int);
669 memcpy(p, argp, arglen);
673 argp = va_arg(args, unsigned char *);
674 arglen = strlen(argp);
675 PUT_32BIT(p, arglen);
676 memcpy(p + 4, argp, arglen);
680 bn = va_arg(args, Bignum);
681 p += ssh1_write_bignum(p, bn);
692 * Connect to specified host and port.
693 * Returns an error message, or NULL on success.
694 * Also places the canonical host name into `realhost'.
696 static char *connect_to_host(char *host, int port, char **realhost)
706 savedhost = malloc(1+strlen(host));
708 fatalbox("Out of memory");
709 strcpy(savedhost, host);
712 port = 22; /* default ssh port */
725 if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
726 if ( (h = gethostbyname(host)) == NULL)
727 switch (WSAGetLastError()) {
728 case WSAENETDOWN: return "Network is down";
729 case WSAHOST_NOT_FOUND: case WSANO_DATA:
730 return "Host does not exist";
731 case WSATRY_AGAIN: return "Host not found";
732 default: return "gethostbyname: unknown error";
734 memcpy (&a, h->h_addr, sizeof(a));
735 *realhost = h->h_name;
746 s = socket(AF_INET, SOCK_STREAM, 0);
747 if (s == INVALID_SOCKET)
748 switch (WSAGetLastError()) {
749 case WSAENETDOWN: return "Network is down";
750 case WSAEAFNOSUPPORT: return "TCP/IP support not present";
751 default: return "socket(): unknown error";
755 * Bind to local address.
757 addr.sin_family = AF_INET;
758 addr.sin_addr.s_addr = htonl(INADDR_ANY);
759 addr.sin_port = htons(0);
760 if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
761 switch (WSAGetLastError()) {
762 case WSAENETDOWN: return "Network is down";
763 default: return "bind(): unknown error";
767 * Connect to remote address.
769 addr.sin_addr.s_addr = htonl(a);
770 addr.sin_port = htons((short)port);
771 if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
772 switch (WSAGetLastError()) {
773 case WSAENETDOWN: return "Network is down";
774 case WSAECONNREFUSED: return "Connection refused";
775 case WSAENETUNREACH: return "Network is unreachable";
776 case WSAEHOSTUNREACH: return "No route to host";
777 default: return "connect(): unknown error";
781 send(s, "connect ", 8, 0);
782 send(s, FWhost, strlen(FWhost), 0);
785 sprintf(buf, " %d\n", FWport);
786 send (s, buf, strlen(buf), 0);
793 static int ssh_versioncmp(char *a, char *b) {
795 unsigned long av, bv;
797 av = strtoul(a, &ae, 10);
798 bv = strtoul(b, &be, 10);
799 if (av != bv) return (av < bv ? -1 : +1);
800 if (*ae == '.') ae++;
801 if (*be == '.') be++;
802 av = strtoul(ae, &ae, 10);
803 bv = strtoul(be, &be, 10);
804 if (av != bv) return (av < bv ? -1 : +1);
810 * Utility routine for putting an SSH-protocol `string' into a SHA
814 static void sha_string(SHA_State *s, void *str, int len) {
815 unsigned char lenblk[4];
816 PUT_32BIT(lenblk, len);
817 SHA_Bytes(s, lenblk, 4);
818 SHA_Bytes(s, str, len);
822 * SSH2 packet construction functions.
824 static void ssh2_pkt_adddata(void *data, int len) {
825 pktout.length += len;
826 if (pktout.maxlen < pktout.length) {
827 pktout.maxlen = pktout.length + 256;
828 pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) :
829 realloc(pktout.data, pktout.maxlen+APIEXTRA));
831 fatalbox("Out of memory");
833 memcpy(pktout.data+pktout.length-len, data, len);
835 static void ssh2_pkt_addbyte(unsigned char byte) {
836 ssh2_pkt_adddata(&byte, 1);
838 static void ssh2_pkt_init(int pkt_type) {
840 ssh2_pkt_addbyte((unsigned char)pkt_type);
842 static void ssh2_pkt_addbool(unsigned char value) {
843 ssh2_pkt_adddata(&value, 1);
845 static void ssh2_pkt_adduint32(unsigned long value) {
848 ssh2_pkt_adddata(x, 4);
850 static void ssh2_pkt_addstring_start(void) {
851 ssh2_pkt_adduint32(0);
852 pktout.savedpos = pktout.length;
854 static void ssh2_pkt_addstring_str(char *data) {
855 ssh2_pkt_adddata(data, strlen(data));
856 PUT_32BIT(pktout.data + pktout.savedpos - 4,
857 pktout.length - pktout.savedpos);
859 static void ssh2_pkt_addstring_data(char *data, int len) {
860 ssh2_pkt_adddata(data, len);
861 PUT_32BIT(pktout.data + pktout.savedpos - 4,
862 pktout.length - pktout.savedpos);
864 static void ssh2_pkt_addstring(char *data) {
865 ssh2_pkt_addstring_start();
866 ssh2_pkt_addstring_str(data);
868 static char *ssh2_mpint_fmt(Bignum b, int *len) {
871 p = malloc(n * 2 + 1);
873 fatalbox("out of memory");
875 for (i = 0; i < n; i++) {
876 p[i*2+1] = (b[n-i] >> 8) & 0xFF;
877 p[i*2+2] = (b[n-i] ) & 0xFF;
880 while (p[i] == 0 && (p[i+1] & 0x80) == 0)
882 memmove(p, p+i, n*2+1-i);
886 static void ssh2_pkt_addmp(Bignum b) {
889 p = ssh2_mpint_fmt(b, &len);
890 ssh2_pkt_addstring_start();
891 ssh2_pkt_addstring_data(p, len);
894 static void ssh2_pkt_send(void) {
895 int cipherblk, maclen, padding, i;
896 static unsigned long outgoing_sequence = 0;
899 * Add padding. At least four bytes, and must also bring total
900 * length (minus MAC) up to a multiple of the block size.
902 cipherblk = cipher ? cipher->blksize : 8; /* block size */
903 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
905 padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
906 pktout.data[4] = padding;
907 for (i = 0; i < padding; i++)
908 pktout.data[pktout.length + i] = random_byte();
909 PUT_32BIT(pktout.data, pktout.length + padding - 4);
911 csmac->generate(pktout.data, pktout.length + padding,
913 outgoing_sequence++; /* whether or not we MACed */
916 debug(("Sending packet len=%d\r\n", pktout.length+padding));
917 for (i = 0; i < pktout.length+padding; i++)
918 debug((" %02x", (unsigned char)pktout.data[i]));
923 cscipher->encrypt(pktout.data, pktout.length + padding);
924 maclen = csmac ? csmac->len : 0;
926 s_write(pktout.data, pktout.length + padding + maclen);
930 void bndebug(char *string, Bignum b) {
933 p = ssh2_mpint_fmt(b, &len);
934 debug(("%s", string));
935 for (i = 0; i < len; i++)
936 debug((" %02x", p[i]));
942 static void sha_mpint(SHA_State *s, Bignum b) {
945 p = ssh2_mpint_fmt(b, &len);
946 sha_string(s, p, len);
951 * SSH2 packet decode functions.
953 static unsigned long ssh2_pkt_getuint32(void) {
955 if (pktin.length - pktin.savedpos < 4)
956 return 0; /* arrgh, no way to decline (FIXME?) */
957 value = GET_32BIT(pktin.data+pktin.savedpos);
961 static void ssh2_pkt_getstring(char **p, int *length) {
963 if (pktin.length - pktin.savedpos < 4)
965 *length = GET_32BIT(pktin.data+pktin.savedpos);
967 if (pktin.length - pktin.savedpos < *length)
969 *p = pktin.data+pktin.savedpos;
970 pktin.savedpos += *length;
972 static Bignum ssh2_pkt_getmp(void) {
977 ssh2_pkt_getstring(&p, &length);
981 bombout(("internal error: Can't handle negative mpints"));
984 b = newbn((length+1)/2);
985 for (i = 0; i < length; i++) {
988 b[j/2+1] |= ((unsigned char)p[i]) << 8;
990 b[j/2+1] |= ((unsigned char)p[i]);
995 static int do_ssh_init(void) {
999 char vlog[sizeof(vstring)+20];
1004 while (s_read(&c, 1) == 1) {
1005 if (c == 'S' && i < 2) i++;
1006 else if (c == 'S' && i == 2) i = 2;
1007 else if (c == 'H' && i == 2) break;
1011 if (s_read(&c,1) != 1 || c != 'S') return 0;
1012 if (s_read(&c,1) != 1 || c != 'S') return 0;
1013 if (s_read(&c,1) != 1 || c != 'H') return 0;
1015 strcpy(vstring, "SSH-");
1017 if (s_read(&c,1) != 1 || c != '-') return 0;
1020 if (s_read(&c,1) != 1)
1022 if (vsp < vstring+sizeof(vstring)-1)
1028 } else if (i < sizeof(version)-1)
1035 rdpkt2_state.incoming_sequence = 0;
1038 sprintf(vlog, "Server version: %s", vstring);
1039 vlog[strcspn(vlog, "\r\n")] = '\0';
1043 * Server version "1.99" means we can choose whether we use v1
1044 * or v2 protocol. Choice is based on cfg.sshprot.
1046 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
1048 * This is a v2 server. Begin v2 protocol.
1050 char *verstring = "SSH-2.0-PuTTY";
1053 * Hash our version string and their version string.
1055 sha_string(&exhash, verstring, strlen(verstring));
1056 sha_string(&exhash, vstring, strcspn(vstring, "\r\n"));
1057 sprintf(vstring, "%s\n", verstring);
1058 sprintf(vlog, "We claim version: %s", verstring);
1060 logevent("Using SSH protocol version 2");
1061 s_write(vstring, strlen(vstring));
1062 ssh_protocol = ssh2_protocol;
1064 s_rdpkt = ssh2_rdpkt;
1067 * This is a v1 server. Begin v1 protocol.
1069 sprintf(vstring, "SSH-%s-PuTTY\n",
1070 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
1071 sprintf(vlog, "We claim version: %s", vstring);
1072 vlog[strcspn(vlog, "\r\n")] = '\0';
1074 logevent("Using SSH protocol version 1");
1075 s_write(vstring, strlen(vstring));
1076 ssh_protocol = ssh1_protocol;
1078 s_rdpkt = ssh1_rdpkt;
1085 * Handle the key exchange and user authentication phases.
1087 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1090 unsigned char *rsabuf, *keystr1, *keystr2;
1091 unsigned char cookie[8];
1092 struct RSAKey servkey, hostkey;
1093 struct MD5Context md5c;
1094 static unsigned long supported_ciphers_mask, supported_auths_mask;
1095 static int tried_publickey;
1096 static unsigned char session_id[16];
1098 static char username[100];
1102 if (!ispkt) crWaitUntil(ispkt);
1104 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1105 bombout(("Public key packet not received"));
1109 logevent("Received public keys");
1111 memcpy(cookie, pktin.body, 8);
1113 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1114 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
1117 * Log the host key fingerprint.
1121 logevent("Host key fingerprint is:");
1122 strcpy(logmsg, " ");
1123 hostkey.comment = NULL;
1124 rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg),
1129 supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
1130 supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
1133 MD5Update(&md5c, keystr2, hostkey.bytes);
1134 MD5Update(&md5c, keystr1, servkey.bytes);
1135 MD5Update(&md5c, pktin.body, 8);
1136 MD5Final(session_id, &md5c);
1138 for (i=0; i<32; i++)
1139 session_key[i] = random_byte();
1141 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
1143 rsabuf = malloc(len);
1145 fatalbox("Out of memory");
1148 * Verify the host key.
1152 * First format the key into a string.
1154 int len = rsastr_len(&hostkey);
1155 char fingerprint[100];
1156 char *keystr = malloc(len);
1158 fatalbox("Out of memory");
1159 rsastr_fmt(keystr, &hostkey);
1160 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
1161 verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint);
1165 for (i=0; i<32; i++) {
1166 rsabuf[i] = session_key[i];
1168 rsabuf[i] ^= session_id[i];
1171 if (hostkey.bytes > servkey.bytes) {
1172 rsaencrypt(rsabuf, 32, &servkey);
1173 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1175 rsaencrypt(rsabuf, 32, &hostkey);
1176 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1179 logevent("Encrypted session key");
1181 cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
1182 cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
1184 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1185 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1186 cipher_type = SSH_CIPHER_3DES;
1188 switch (cipher_type) {
1189 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1190 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1191 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1194 send_packet(SSH1_CMSG_SESSION_KEY,
1195 PKT_CHAR, cipher_type,
1196 PKT_DATA, cookie, 8,
1197 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1198 PKT_DATA, rsabuf, len,
1202 logevent("Trying to enable encryption...");
1206 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
1207 cipher_type == SSH_CIPHER_DES ? &ssh_des :
1209 cipher->sesskey(session_key);
1213 if (pktin.type != SSH1_SMSG_SUCCESS) {
1214 bombout(("Encryption not successfully enabled"));
1218 logevent("Successfully started encryption");
1224 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
1225 c_write("login as: ", 10);
1228 crWaitUntil(!ispkt);
1229 while (inlen--) switch (c = *in++) {
1236 c_write("\b \b", 3);
1242 c_write("\b \b", 3);
1251 if (((c >= ' ' && c <= '~') ||
1252 ((unsigned char)c >= 160)) && pos < 40) {
1253 username[pos++] = c;
1260 username[strcspn(username, "\n\r")] = '\0';
1263 strncpy(username, cfg.username, 99);
1264 username[99] = '\0';
1265 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
1266 sprintf(stuff, "Sent username \"%s\".\r\n", username);
1267 c_write(stuff, strlen(stuff));
1271 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
1273 char userlog[20+sizeof(username)];
1274 sprintf(userlog, "Sent username \"%s\"", username);
1281 tried_publickey = 0;
1283 while (pktin.type == SSH1_SMSG_FAILURE) {
1284 static char password[100];
1285 static char prompt[200];
1288 static int pwpkt_type;
1290 * Show password prompt, having first obtained it via a TIS
1291 * or CryptoCard exchange if we're doing TIS or CryptoCard
1294 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
1295 if (agent_exists()) {
1297 * Attempt RSA authentication using Pageant.
1299 static unsigned char request[5], *response, *p;
1300 static int responselen;
1301 static int i, nkeys;
1302 static int authed = FALSE;
1305 logevent("Pageant is running. Requesting keys.");
1307 /* Request the keys held by the agent. */
1308 PUT_32BIT(request, 1);
1309 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1310 agent_query(request, 5, &r, &responselen);
1311 response = (unsigned char *)r;
1314 nkeys = GET_32BIT(p); p += 4;
1315 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1317 for (i = 0; i < nkeys; i++) {
1318 static struct RSAKey key;
1319 static Bignum challenge;
1320 static char *commentp;
1321 static int commentlen;
1323 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1326 p += ssh1_read_bignum(p, &key.exponent);
1327 p += ssh1_read_bignum(p, &key.modulus);
1328 commentlen = GET_32BIT(p); p += 4;
1329 commentp = p; p += commentlen;
1330 send_packet(SSH1_CMSG_AUTH_RSA,
1331 PKT_BIGNUM, key.modulus, PKT_END);
1333 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1334 logevent("Key refused");
1337 logevent("Received RSA challenge");
1338 ssh1_read_bignum(pktin.body, &challenge);
1340 char *agentreq, *q, *ret;
1342 len = 1 + 4; /* message type, bit count */
1343 len += ssh1_bignum_length(key.exponent);
1344 len += ssh1_bignum_length(key.modulus);
1345 len += ssh1_bignum_length(challenge);
1346 len += 16; /* session id */
1347 len += 4; /* response format */
1348 agentreq = malloc(4 + len);
1349 PUT_32BIT(agentreq, len);
1351 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1352 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1354 q += ssh1_write_bignum(q, key.exponent);
1355 q += ssh1_write_bignum(q, key.modulus);
1356 q += ssh1_write_bignum(q, challenge);
1357 memcpy(q, session_id, 16); q += 16;
1358 PUT_32BIT(q, 1); /* response format */
1359 agent_query(agentreq, len+4, &ret, &retlen);
1362 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1363 logevent("Sending Pageant's response");
1364 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1365 PKT_DATA, ret+5, 16, PKT_END);
1368 if (pktin.type == SSH1_SMSG_SUCCESS) {
1369 logevent("Pageant's response accepted");
1370 if (flags & FLAG_VERBOSE) {
1371 c_write("Authenticated using RSA key \"",
1373 c_write(commentp, commentlen);
1374 c_write("\" from agent\r\n", 14);
1378 logevent("Pageant's response not accepted");
1380 logevent("Pageant failed to answer challenge");
1384 logevent("No reply received from Pageant");
1387 freebn(key.exponent);
1388 freebn(key.modulus);
1397 if (*cfg.keyfile && !tried_publickey)
1398 pwpkt_type = SSH1_CMSG_AUTH_RSA;
1400 if (pktin.type == SSH1_SMSG_FAILURE &&
1402 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1403 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1404 logevent("Requested TIS authentication");
1405 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1407 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1408 logevent("TIS authentication declined");
1409 if (flags & FLAG_INTERACTIVE)
1410 c_write("TIS authentication refused.\r\n", 29);
1412 int challengelen = ((pktin.body[0] << 24) |
1413 (pktin.body[1] << 16) |
1414 (pktin.body[2] << 8) |
1416 logevent("Received TIS challenge");
1417 if (challengelen > sizeof(prompt)-1)
1418 challengelen = sizeof(prompt)-1; /* prevent overrun */
1419 memcpy(prompt, pktin.body+4, challengelen);
1420 prompt[challengelen] = '\0';
1423 if (pktin.type == SSH1_SMSG_FAILURE &&
1425 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1426 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1427 logevent("Requested CryptoCard authentication");
1428 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1430 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1431 logevent("CryptoCard authentication declined");
1432 c_write("CryptoCard authentication refused.\r\n", 29);
1434 int challengelen = ((pktin.body[0] << 24) |
1435 (pktin.body[1] << 16) |
1436 (pktin.body[2] << 8) |
1438 logevent("Received CryptoCard challenge");
1439 if (challengelen > sizeof(prompt)-1)
1440 challengelen = sizeof(prompt)-1; /* prevent overrun */
1441 memcpy(prompt, pktin.body+4, challengelen);
1442 strncpy(prompt + challengelen, "\r\nResponse : ",
1443 sizeof(prompt)-challengelen);
1444 prompt[sizeof(prompt)-1] = '\0';
1447 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
1448 sprintf(prompt, "%.90s@%.90s's password: ",
1449 username, savedhost);
1451 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1452 char *comment = NULL;
1453 if (flags & FLAG_VERBOSE)
1454 c_write("Trying public key authentication.\r\n", 35);
1455 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
1456 if (flags & FLAG_VERBOSE)
1457 c_write("No passphrase required.\r\n", 25);
1460 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
1464 if (ssh_get_password) {
1465 if (!ssh_get_password(prompt, password, sizeof(password))) {
1467 * get_password failed to get a password (for
1468 * example because one was supplied on the command
1469 * line which has already failed to work).
1472 logevent("No more passwords to try");
1473 ssh_state = SSH_STATE_CLOSED;
1477 c_write(prompt, strlen(prompt));
1481 crWaitUntil(!ispkt);
1482 while (inlen--) switch (c = *in++) {
1499 if (((c >= ' ' && c <= '~') ||
1500 ((unsigned char)c >= 160)) && pos < sizeof(password))
1501 password[pos++] = c;
1509 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1511 * Try public key authentication with the specified
1514 static struct RSAKey pubkey;
1515 static Bignum challenge, response;
1517 static unsigned char buffer[32];
1519 tried_publickey = 1;
1520 i = loadrsakey(cfg.keyfile, &pubkey, password);
1522 c_write("Couldn't load public key from ", 30);
1523 c_write(cfg.keyfile, strlen(cfg.keyfile));
1524 c_write(".\r\n", 3);
1525 continue; /* go and try password */
1528 c_write("Wrong passphrase.\r\n", 19);
1529 tried_publickey = 0;
1530 continue; /* try again */
1534 * Send a public key attempt.
1536 send_packet(SSH1_CMSG_AUTH_RSA,
1537 PKT_BIGNUM, pubkey.modulus, PKT_END);
1540 if (pktin.type == SSH1_SMSG_FAILURE) {
1541 c_write("Server refused our public key.\r\n", 32);
1542 continue; /* go and try password */
1544 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1545 bombout(("Bizarre response to offer of public key"));
1548 ssh1_read_bignum(pktin.body, &challenge);
1549 response = rsadecrypt(challenge, &pubkey);
1550 freebn(pubkey.private_exponent); /* burn the evidence */
1552 for (i = 0; i < 32; i += 2) {
1553 buffer[i] = response[16-i/2] >> 8;
1554 buffer[i+1] = response[16-i/2] & 0xFF;
1558 MD5Update(&md5c, buffer, 32);
1559 MD5Update(&md5c, session_id, 16);
1560 MD5Final(buffer, &md5c);
1562 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1563 PKT_DATA, buffer, 16, PKT_END);
1566 if (pktin.type == SSH1_SMSG_FAILURE) {
1567 if (flags & FLAG_VERBOSE)
1568 c_write("Failed to authenticate with our public key.\r\n",
1570 continue; /* go and try password */
1571 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1572 bombout(("Bizarre response to RSA authentication response"));
1576 break; /* we're through! */
1578 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1580 logevent("Sent password");
1581 memset(password, 0, strlen(password));
1583 if (pktin.type == SSH1_SMSG_FAILURE) {
1584 if (flags & FLAG_VERBOSE)
1585 c_write("Access denied\r\n", 15);
1586 logevent("Authentication refused");
1587 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1588 logevent("Received disconnect request");
1589 ssh_state = SSH_STATE_CLOSED;
1591 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1592 bombout(("Strange packet received, type %d", pktin.type));
1597 logevent("Authentication successful");
1602 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
1607 while (!do_ssh1_login(in, inlen, ispkt)) {
1610 if (ssh_state == SSH_STATE_CLOSED)
1613 if (cfg.agentfwd && agent_exists()) {
1614 logevent("Requesting agent forwarding");
1615 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1616 do { crReturnV; } while (!ispkt);
1617 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1618 bombout(("Protocol confusion"));
1620 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1621 logevent("Agent forwarding refused");
1623 logevent("Agent forwarding enabled");
1627 send_packet(SSH1_CMSG_REQUEST_PTY,
1628 PKT_STR, cfg.termtype,
1629 PKT_INT, rows, PKT_INT, cols,
1630 PKT_INT, 0, PKT_INT, 0,
1633 ssh_state = SSH_STATE_INTERMED;
1634 do { crReturnV; } while (!ispkt);
1635 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1636 bombout(("Protocol confusion"));
1638 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1639 c_write("Server refused to allocate pty\r\n", 32);
1641 logevent("Allocated pty");
1644 if (*cfg.remote_cmd)
1645 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1647 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
1648 logevent("Started session");
1650 ssh_state = SSH_STATE_SESSION;
1655 ssh_channels = newtree234(ssh_channelcmp);
1660 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1661 pktin.type == SSH1_SMSG_STDERR_DATA) {
1662 long len = GET_32BIT(pktin.body);
1663 c_writedata(pktin.body+4, len);
1664 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1665 ssh_state = SSH_STATE_CLOSED;
1666 logevent("Received disconnect request");
1667 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
1668 /* Remote side is trying to open a channel to talk to our
1669 * agent. Give them back a local channel number. */
1671 struct ssh_channel *c;
1673 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
1675 break; /* found a free number */
1678 c = malloc(sizeof(struct ssh_channel));
1679 c->remoteid = GET_32BIT(pktin.body);
1682 c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */
1683 c->u.a.lensofar = 0;
1684 add234(ssh_channels, c);
1685 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1686 PKT_INT, c->remoteid, PKT_INT, c->localid,
1688 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
1689 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
1690 /* Remote side closes a channel. */
1691 unsigned i = GET_32BIT(pktin.body);
1692 struct ssh_channel *c;
1693 c = find234(ssh_channels, &i, ssh_channelfind);
1696 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
1697 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
1698 c->closes |= closetype;
1699 if (c->closes == 3) {
1700 del234(ssh_channels, c);
1704 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
1705 /* Data sent down one of our channels. */
1706 int i = GET_32BIT(pktin.body);
1707 int len = GET_32BIT(pktin.body+4);
1708 unsigned char *p = pktin.body+8;
1709 struct ssh_channel *c;
1710 c = find234(ssh_channels, &i, ssh_channelfind);
1713 case SSH1_SMSG_AGENT_OPEN:
1714 /* Data for an agent message. Buffer it. */
1716 if (c->u.a.lensofar < 4) {
1717 int l = min(4 - c->u.a.lensofar, len);
1718 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
1719 p += l; len -= l; c->u.a.lensofar += l;
1721 if (c->u.a.lensofar == 4) {
1722 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
1723 c->u.a.message = malloc(c->u.a.totallen);
1724 memcpy(c->u.a.message, c->u.a.msglen, 4);
1726 if (c->u.a.lensofar >= 4 && len > 0) {
1727 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
1728 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
1729 p += l; len -= l; c->u.a.lensofar += l;
1731 if (c->u.a.lensofar == c->u.a.totallen) {
1732 void *reply, *sentreply;
1734 agent_query(c->u.a.message, c->u.a.totallen,
1739 /* Fake SSH_AGENT_FAILURE. */
1740 sentreply = "\0\0\0\1\5";
1743 send_packet(SSH1_MSG_CHANNEL_DATA,
1744 PKT_INT, c->remoteid,
1746 PKT_DATA, sentreply, replylen,
1750 free(c->u.a.message);
1751 c->u.a.lensofar = 0;
1757 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
1758 /* may be from EXEC_SHELL on some servers */
1759 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1760 /* may be from EXEC_SHELL on some servers
1761 * if no pty is available or in other odd cases. Ignore */
1762 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
1763 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
1765 bombout(("Strange packet received: type %d", pktin.type));
1769 send_packet(SSH1_CMSG_STDIN_DATA,
1770 PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END);
1778 * Utility routine for decoding comma-separated strings in KEXINIT.
1780 static int in_commasep_string(char *needle, char *haystack, int haylen) {
1781 int needlen = strlen(needle);
1784 * Is it at the start of the string?
1786 if (haylen >= needlen && /* haystack is long enough */
1787 !memcmp(needle, haystack, needlen) && /* initial match */
1788 (haylen == needlen || haystack[needlen] == ',')
1789 /* either , or EOS follows */
1793 * If not, search for the next comma and resume after that.
1794 * If no comma found, terminate.
1796 while (haylen > 0 && *haystack != ',')
1797 haylen--, haystack++;
1800 haylen--, haystack++; /* skip over comma itself */
1805 * SSH2 key creation method.
1807 static void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
1809 /* First 20 bytes. */
1812 SHA_Bytes(&s, H, 20);
1813 SHA_Bytes(&s, &chr, 1);
1814 SHA_Bytes(&s, H, 20);
1815 SHA_Final(&s, keyspace);
1816 /* Next 20 bytes. */
1819 SHA_Bytes(&s, H, 20);
1820 SHA_Bytes(&s, keyspace, 20);
1821 SHA_Final(&s, keyspace+20);
1825 * Handle the SSH2 transport layer.
1827 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
1831 static Bignum e, f, K;
1832 static const struct ssh_mac **maclist;
1833 static const struct ssh_cipher *cscipher_tobe = NULL;
1834 static const struct ssh_cipher *sccipher_tobe = NULL;
1835 static const struct ssh_mac *csmac_tobe = NULL;
1836 static const struct ssh_mac *scmac_tobe = NULL;
1837 static const struct ssh_compress *cscomp_tobe = NULL;
1838 static const struct ssh_compress *sccomp_tobe = NULL;
1839 static char *hostkeydata, *sigdata, *keystr, *fingerprint;
1840 static int hostkeylen, siglen;
1841 static unsigned char exchange_hash[20];
1842 static unsigned char keyspace[40];
1843 static const struct ssh_cipher *preferred_cipher;
1849 * Set up the preferred cipher.
1851 if (cfg.cipher == CIPHER_BLOWFISH) {
1852 preferred_cipher = &ssh_blowfish_ssh2;
1853 } else if (cfg.cipher == CIPHER_DES) {
1854 logevent("Single DES not supported in SSH2; using 3DES");
1855 preferred_cipher = &ssh_3des_ssh2;
1856 } else if (cfg.cipher == CIPHER_3DES) {
1857 preferred_cipher = &ssh_3des_ssh2;
1859 /* Shouldn't happen, but we do want to initialise to _something_. */
1860 preferred_cipher = &ssh_3des_ssh2;
1864 * Be prepared to work around the buggy MAC problem.
1867 maclist = buggymacs;
1873 * Construct and send our key exchange packet.
1875 ssh2_pkt_init(SSH2_MSG_KEXINIT);
1876 for (i = 0; i < 16; i++)
1877 ssh2_pkt_addbyte((unsigned char)random_byte());
1878 /* List key exchange algorithms. */
1879 ssh2_pkt_addstring_start();
1880 for (i = 0; i < lenof(kex_algs); i++) {
1881 ssh2_pkt_addstring_str(kex_algs[i]->name);
1882 if (i < lenof(kex_algs)-1)
1883 ssh2_pkt_addstring_str(",");
1885 /* List server host key algorithms. */
1886 ssh2_pkt_addstring_start();
1887 for (i = 0; i < lenof(hostkey_algs); i++) {
1888 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
1889 if (i < lenof(hostkey_algs)-1)
1890 ssh2_pkt_addstring_str(",");
1892 /* List client->server encryption algorithms. */
1893 ssh2_pkt_addstring_start();
1894 for (i = 0; i < lenof(ciphers)+1; i++) {
1895 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1896 ssh2_pkt_addstring_str(c->name);
1897 if (i < lenof(ciphers))
1898 ssh2_pkt_addstring_str(",");
1900 /* List server->client encryption algorithms. */
1901 ssh2_pkt_addstring_start();
1902 for (i = 0; i < lenof(ciphers)+1; i++) {
1903 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1904 ssh2_pkt_addstring_str(c->name);
1905 if (i < lenof(ciphers))
1906 ssh2_pkt_addstring_str(",");
1908 /* List client->server MAC algorithms. */
1909 ssh2_pkt_addstring_start();
1910 for (i = 0; i < lenof(maclist); i++) {
1911 ssh2_pkt_addstring_str(maclist[i]->name);
1912 if (i < lenof(maclist)-1)
1913 ssh2_pkt_addstring_str(",");
1915 /* List server->client MAC algorithms. */
1916 ssh2_pkt_addstring_start();
1917 for (i = 0; i < lenof(maclist); i++) {
1918 ssh2_pkt_addstring_str(maclist[i]->name);
1919 if (i < lenof(maclist)-1)
1920 ssh2_pkt_addstring_str(",");
1922 /* List client->server compression algorithms. */
1923 ssh2_pkt_addstring_start();
1924 for (i = 0; i < lenof(compressions); i++) {
1925 ssh2_pkt_addstring_str(compressions[i]->name);
1926 if (i < lenof(compressions)-1)
1927 ssh2_pkt_addstring_str(",");
1929 /* List server->client compression algorithms. */
1930 ssh2_pkt_addstring_start();
1931 for (i = 0; i < lenof(compressions); i++) {
1932 ssh2_pkt_addstring_str(compressions[i]->name);
1933 if (i < lenof(compressions)-1)
1934 ssh2_pkt_addstring_str(",");
1936 /* List client->server languages. Empty list. */
1937 ssh2_pkt_addstring_start();
1938 /* List server->client languages. Empty list. */
1939 ssh2_pkt_addstring_start();
1940 /* First KEX packet does _not_ follow, because we're not that brave. */
1941 ssh2_pkt_addbool(FALSE);
1943 ssh2_pkt_adduint32(0);
1944 sha_string(&exhash, pktout.data+5, pktout.length-5);
1947 if (!ispkt) crWaitUntil(ispkt);
1948 sha_string(&exhash, pktin.data+5, pktin.length-5);
1951 * Now examine the other side's KEXINIT to see what we're up
1954 if (pktin.type != SSH2_MSG_KEXINIT) {
1955 bombout(("expected key exchange packet from server"));
1958 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
1959 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
1960 pktin.savedpos += 16; /* skip garbage cookie */
1961 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
1962 for (i = 0; i < lenof(kex_algs); i++) {
1963 if (in_commasep_string(kex_algs[i]->name, str, len)) {
1968 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
1969 for (i = 0; i < lenof(hostkey_algs); i++) {
1970 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
1971 hostkey = hostkey_algs[i];
1975 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
1976 for (i = 0; i < lenof(ciphers)+1; i++) {
1977 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1978 if (in_commasep_string(c->name, str, len)) {
1983 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
1984 for (i = 0; i < lenof(ciphers)+1; i++) {
1985 const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
1986 if (in_commasep_string(c->name, str, len)) {
1991 ssh2_pkt_getstring(&str, &len); /* client->server mac */
1992 for (i = 0; i < lenof(maclist); i++) {
1993 if (in_commasep_string(maclist[i]->name, str, len)) {
1994 csmac_tobe = maclist[i];
1998 ssh2_pkt_getstring(&str, &len); /* server->client mac */
1999 for (i = 0; i < lenof(maclist); i++) {
2000 if (in_commasep_string(maclist[i]->name, str, len)) {
2001 scmac_tobe = maclist[i];
2005 ssh2_pkt_getstring(&str, &len); /* client->server compression */
2006 for (i = 0; i < lenof(compressions); i++) {
2007 if (in_commasep_string(compressions[i]->name, str, len)) {
2008 cscomp_tobe = compressions[i];
2012 ssh2_pkt_getstring(&str, &len); /* server->client compression */
2013 for (i = 0; i < lenof(compressions); i++) {
2014 if (in_commasep_string(compressions[i]->name, str, len)) {
2015 sccomp_tobe = compressions[i];
2021 * Currently we only support Diffie-Hellman and DSS, so let's
2022 * bomb out if those aren't selected.
2024 if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
2025 bombout(("internal fault: chaos in SSH 2 transport layer"));
2030 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2033 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
2038 if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
2039 bombout(("expected key exchange packet from server"));
2042 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2043 f = ssh2_pkt_getmp();
2044 ssh2_pkt_getstring(&sigdata, &siglen);
2048 sha_string(&exhash, hostkeydata, hostkeylen);
2049 sha_mpint(&exhash, e);
2050 sha_mpint(&exhash, f);
2051 sha_mpint(&exhash, K);
2052 SHA_Final(&exhash, exchange_hash);
2055 debug(("Exchange hash is:\r\n"));
2056 for (i = 0; i < 20; i++)
2057 debug((" %02x", exchange_hash[i]));
2061 hostkey->setkey(hostkeydata, hostkeylen);
2062 if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) {
2063 bombout(("Server failed host key check"));
2068 * Expect SSH2_MSG_NEWKEYS from server.
2071 if (pktin.type != SSH2_MSG_NEWKEYS) {
2072 bombout(("expected new-keys packet from server"));
2077 * Authenticate remote host: verify host key. (We've already
2078 * checked the signature of the exchange hash.)
2080 keystr = hostkey->fmtkey();
2081 fingerprint = hostkey->fingerprint();
2082 verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
2083 keystr, fingerprint);
2084 logevent("Host key fingerprint is:");
2085 logevent(fingerprint);
2090 * Send SSH2_MSG_NEWKEYS.
2092 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2096 * Create and initialise session keys.
2098 cscipher = cscipher_tobe;
2099 sccipher = sccipher_tobe;
2102 cscomp = cscomp_tobe;
2103 sccomp = sccomp_tobe;
2105 * Set IVs after keys.
2107 ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
2108 ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
2109 ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
2110 ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
2111 ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
2112 ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
2115 * Now we're encrypting. Begin returning 1 to the protocol main
2116 * function so that other things can run on top of the
2117 * transport. If we ever see a KEXINIT, we must go back to the
2122 } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
2123 goto begin_key_exchange;
2129 * Handle the SSH2 userauth and connection layers.
2131 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2133 static unsigned long remote_winsize;
2134 static unsigned long remote_maxpkt;
2139 * Request userauth protocol, and await a response to it.
2141 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2142 ssh2_pkt_addstring("ssh-userauth");
2144 crWaitUntilV(ispkt);
2145 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2146 bombout(("Server refused user authentication protocol"));
2151 * FIXME: currently we support only password authentication.
2152 * (This places us technically in violation of the SSH2 spec.
2153 * We must fix this.)
2157 * Get a username and a password.
2159 static char username[100];
2160 static char password[100];
2164 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2165 c_write("login as: ", 10);
2168 crWaitUntilV(!ispkt);
2169 while (inlen--) switch (c = *in++) {
2176 c_write("\b \b", 3);
2182 c_write("\b \b", 3);
2191 if (((c >= ' ' && c <= '~') ||
2192 ((unsigned char)c >= 160)) && pos < 40) {
2193 username[pos++] = c;
2200 username[strcspn(username, "\n\r")] = '\0';
2203 strncpy(username, cfg.username, 99);
2204 username[99] = '\0';
2205 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
2206 sprintf(stuff, "Using username \"%s\".\r\n", username);
2207 c_write(stuff, strlen(stuff));
2211 if (ssh_get_password) {
2213 sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost);
2214 if (!ssh_get_password(prompt, password, sizeof(password))) {
2216 * get_password failed to get a password (for
2217 * example because one was supplied on the command
2218 * line which has already failed to work).
2221 logevent("No more passwords to try");
2222 ssh_state = SSH_STATE_CLOSED;
2226 c_write("password: ", 10);
2231 crWaitUntilV(!ispkt);
2232 while (inlen--) switch (c = *in++) {
2249 if (((c >= ' ' && c <= '~') ||
2250 ((unsigned char)c >= 160)) && pos < 40)
2251 password[pos++] = c;
2258 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2259 ssh2_pkt_addstring(username);
2260 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2261 ssh2_pkt_addstring("password");
2262 ssh2_pkt_addbool(FALSE);
2263 ssh2_pkt_addstring(password);
2266 crWaitUntilV(ispkt);
2267 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2268 c_write("Access denied\r\n", 15);
2269 logevent("Authentication refused");
2275 * Now we're authenticated for the connection protocol. The
2276 * connection protocol will automatically have started at this
2277 * point; there's no need to send SERVICE_REQUEST.
2281 * So now create a channel with a session in it.
2283 mainchan = malloc(sizeof(struct ssh_channel));
2284 mainchan->localid = 100; /* as good as any */
2285 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2286 ssh2_pkt_addstring("session");
2287 ssh2_pkt_adduint32(mainchan->localid);
2288 ssh2_pkt_adduint32(0x7FFFFFFFUL); /* our window size */
2289 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
2291 crWaitUntilV(ispkt);
2292 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
2293 bombout(("Server refused to open a session"));
2295 /* FIXME: error data comes back in FAILURE packet */
2297 if (ssh2_pkt_getuint32() != mainchan->localid) {
2298 bombout(("Server's channel confirmation cited wrong channel"));
2301 mainchan->remoteid = ssh2_pkt_getuint32();
2302 mainchan->u.v2.remwindow = ssh2_pkt_getuint32();
2303 mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32();
2304 mainchan->u.v2.outbuffer = NULL;
2305 mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0;
2306 logevent("Opened channel for session");
2309 * Now allocate a pty for the session.
2312 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2313 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2314 ssh2_pkt_addstring("pty-req");
2315 ssh2_pkt_addbool(1); /* want reply */
2316 ssh2_pkt_addstring(cfg.termtype);
2317 ssh2_pkt_adduint32(cols);
2318 ssh2_pkt_adduint32(rows);
2319 ssh2_pkt_adduint32(0); /* pixel width */
2320 ssh2_pkt_adduint32(0); /* pixel height */
2321 ssh2_pkt_addstring_start();
2322 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2326 crWaitUntilV(ispkt);
2327 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2328 /* FIXME: be able to handle other channels here */
2329 if (ssh2_pkt_getuint32() != mainchan->localid)
2330 continue; /* wrong channel */
2331 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2333 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2335 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2336 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2337 bombout(("Server got confused by pty request"));
2340 c_write("Server refused to allocate pty\r\n", 32);
2342 logevent("Allocated pty");
2347 * Start a shell or a remote command.
2349 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2350 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2351 if (*cfg.remote_cmd) {
2352 ssh2_pkt_addstring("exec");
2353 ssh2_pkt_addbool(1); /* want reply */
2354 ssh2_pkt_addstring(cfg.remote_cmd);
2356 ssh2_pkt_addstring("shell");
2357 ssh2_pkt_addbool(1); /* want reply */
2361 crWaitUntilV(ispkt);
2362 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2363 /* FIXME: be able to handle other channels here */
2364 if (ssh2_pkt_getuint32() != mainchan->localid)
2365 continue; /* wrong channel */
2366 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2368 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2369 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2370 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2371 bombout(("Server got confused by shell/command request"));
2374 bombout(("Server refused to start a shell/command"));
2377 logevent("Started a shell/command");
2386 static int try_send;
2390 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2391 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2394 /* FIXME: be able to handle other channels here */
2395 if (ssh2_pkt_getuint32() != mainchan->localid)
2396 continue; /* wrong channel */
2397 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2398 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2399 continue; /* extended but not stderr */
2400 ssh2_pkt_getstring(&data, &length);
2402 c_writedata(data, length);
2404 * Enlarge the window again at the remote side,
2405 * just in case it ever runs down and they fail
2406 * to send us any more data.
2408 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2409 ssh2_pkt_adduint32(mainchan->remoteid);
2410 ssh2_pkt_adduint32(length);
2413 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
2414 ssh_state = SSH_STATE_CLOSED;
2415 logevent("Received disconnect message");
2416 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
2417 continue; /* exit status et al; ignore (FIXME?) */
2418 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
2419 continue; /* remote sends EOF; ignore */
2420 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
2421 /* FIXME: be able to handle other channels here */
2422 if (ssh2_pkt_getuint32() != mainchan->localid)
2423 continue; /* wrong channel */
2424 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2425 ssh2_pkt_adduint32(mainchan->remoteid);
2427 /* FIXME: mark the channel as closed */
2428 if (1 /* FIXME: "all channels are closed" */) {
2429 logevent("All channels closed. Disconnecting");
2430 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
2433 continue; /* remote sends close; ignore (FIXME) */
2434 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2435 /* FIXME: be able to handle other channels here */
2436 if (ssh2_pkt_getuint32() != mainchan->localid)
2437 continue; /* wrong channel */
2438 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2441 bombout(("Strange packet received: type %d", pktin.type));
2446 * We have spare data. Add it to the channel buffer.
2448 if (mainchan->u.v2.outbufsize <
2449 mainchan->u.v2.outbuflen + inlen) {
2450 mainchan->u.v2.outbufsize =
2451 mainchan->u.v2.outbuflen + inlen + 1024;
2452 mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer,
2453 mainchan->u.v2.outbufsize);
2455 memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen,
2457 mainchan->u.v2.outbuflen += inlen;
2462 * Try to send data on the channel if we can. (FIXME:
2463 * on _all_ channels.)
2465 while (mainchan->u.v2.remwindow > 0 &&
2466 mainchan->u.v2.outbuflen > 0) {
2467 unsigned len = mainchan->u.v2.remwindow;
2468 if (len > mainchan->u.v2.outbuflen)
2469 len = mainchan->u.v2.outbuflen;
2470 if (len > mainchan->u.v2.remmaxpkt)
2471 len = mainchan->u.v2.remmaxpkt;
2472 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2473 ssh2_pkt_adduint32(mainchan->remoteid);
2474 ssh2_pkt_addstring_start();
2475 ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len);
2477 mainchan->u.v2.outbuflen -= len;
2478 memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len,
2479 mainchan->u.v2.outbuflen);
2480 mainchan->u.v2.remwindow -= len;
2489 * Handle the top-level SSH2 protocol.
2491 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
2493 if (do_ssh2_transport(in, inlen, ispkt) == 0)
2495 do_ssh2_authconn(in, inlen, ispkt);
2499 * Called to set up the connection. Will arrange for WM_NETEVENT
2500 * messages to be passed to the specified window, whose window
2501 * procedure should then call telnet_msg().
2503 * Returns an error message, or NULL on success.
2505 static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) {
2509 if(crypto_startup() == 0)
2510 return "Microsoft high encryption pack not installed!";
2513 p = connect_to_host(host, port, realhost);
2518 return "Protocol initialisation error";
2520 if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
2521 switch (WSAGetLastError()) {
2522 case WSAENETDOWN: return "Network is down";
2523 default: return "WSAAsyncSelect(): unknown error";
2530 * Process a WM_NETEVENT message. Will return 0 if the connection
2531 * has closed, or <0 for a socket error.
2533 static int ssh_msg (WPARAM wParam, LPARAM lParam) {
2538 * Because reading less than the whole of the available pending
2539 * data can generate an FD_READ event, we need to allow for the
2540 * possibility that FD_READ may arrive with FD_CLOSE already in
2541 * the queue; so it's possible that we can get here even with s
2542 * invalid. If so, we return 1 and don't worry about it.
2544 if (s == INVALID_SOCKET)
2547 if (WSAGETSELECTERROR(lParam) != 0) {
2550 return -WSAGETSELECTERROR(lParam);
2553 switch (WSAGETSELECTEVENT(lParam)) {
2556 ret = recv(s, buf, sizeof(buf), 0);
2557 if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
2559 if (ret < 0) { /* any _other_ error */
2562 return -10000-WSAGetLastError();
2568 ssh_gotdata (buf, ret);
2569 if (ssh_state == SSH_STATE_CLOSED) {
2576 return 1; /* shouldn't happen, but WTF */
2580 * Called to send data down the Telnet connection.
2582 static void ssh_send (char *buf, int len) {
2583 if (s == INVALID_SOCKET)
2586 ssh_protocol(buf, len, 0);
2590 * Called to set the size of the window from Telnet's POV.
2592 static void ssh_size(void) {
2593 switch (ssh_state) {
2594 case SSH_STATE_BEFORE_SIZE:
2595 case SSH_STATE_CLOSED:
2596 break; /* do nothing */
2597 case SSH_STATE_INTERMED:
2598 size_needed = TRUE; /* buffer for later */
2600 case SSH_STATE_SESSION:
2602 send_packet(SSH1_CMSG_WINDOW_SIZE,
2603 PKT_INT, rows, PKT_INT, cols,
2604 PKT_INT, 0, PKT_INT, 0, PKT_END);
2610 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2611 * can send an EOF and collect resulting output (e.g. `plink
2614 static void ssh_special (Telnet_Special code) {
2615 if (code == TS_EOF) {
2616 if (ssh_version == 1) {
2617 send_packet(SSH1_CMSG_EOF, PKT_END);
2619 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
2620 ssh2_pkt_adduint32(mainchan->remoteid);
2623 logevent("Sent EOF message");
2624 } else if (code == TS_PING) {
2625 if (ssh_version == 1) {
2626 send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
2628 ssh2_pkt_init(SSH2_MSG_IGNORE);
2629 ssh2_pkt_addstring_start();
2637 static SOCKET ssh_socket(void) { return s; }
2639 static int ssh_sendok(void) { return ssh_send_ok; }
2641 Backend ssh_backend = {