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 struct ssh_cipher ssh_3des;
151 extern struct ssh_cipher ssh_3des_ssh2;
152 extern struct ssh_cipher ssh_des;
153 extern struct ssh_cipher ssh_blowfish_ssh1;
154 extern 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 * The first entry in this array is set up to be whatever the user
163 * asks for as a cipher. Thereafter there is a fixed preference
164 * order of fallback ciphers.
166 struct ssh_cipher *ciphers[] = { NULL, &ssh_blowfish_ssh2, &ssh_3des_ssh2 };
168 extern struct ssh_kex ssh_diffiehellman;
169 struct ssh_kex *kex_algs[] = { &ssh_diffiehellman };
171 extern struct ssh_hostkey ssh_dss;
172 struct ssh_hostkey *hostkey_algs[] = { &ssh_dss };
174 extern struct ssh_mac ssh_sha1;
176 static SHA_State exhash;
178 static void nullmac_key(unsigned char *key) { }
179 static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { }
180 static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; }
181 struct ssh_mac ssh_mac_none = {
182 nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
184 struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none };
186 struct ssh_compress ssh_comp_none = {
189 struct ssh_compress *compressions[] = { &ssh_comp_none };
191 static SOCKET s = INVALID_SOCKET;
193 static unsigned char session_key[32];
194 static struct ssh_cipher *cipher = NULL;
195 static struct ssh_cipher *cscipher = NULL;
196 static struct ssh_cipher *sccipher = NULL;
197 static struct ssh_mac *csmac = NULL;
198 static struct ssh_mac *scmac = NULL;
199 static struct ssh_compress *cscomp = NULL;
200 static struct ssh_compress *sccomp = NULL;
201 static struct ssh_kex *kex = NULL;
202 static struct ssh_hostkey *hostkey = NULL;
203 int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
205 static char *savedhost;
206 static int ssh_send_ok;
209 * 2-3-4 tree storing channels.
212 unsigned remoteid, localid;
216 struct ssh_agent_channel {
217 unsigned char *message;
218 unsigned char msglen[4];
219 int lensofar, totallen;
221 struct ssh2_data_channel {
222 unsigned char *outbuffer;
223 unsigned outbuflen, outbufsize;
224 unsigned remwindow, remmaxpkt;
228 static tree234 *ssh_channels; /* indexed by local id */
229 static int ssh_channelcmp(void *av, void *bv) {
230 struct ssh_channel *a = (struct ssh_channel *)av;
231 struct ssh_channel *b = (struct ssh_channel *)bv;
232 if (a->localid < b->localid) return -1;
233 if (a->localid > b->localid) return +1;
236 static int ssh_channelfind(void *av, void *bv) {
237 unsigned *a = (unsigned *)av;
238 struct ssh_channel *b = (struct ssh_channel *)bv;
239 if (*a < b->localid) return -1;
240 if (*a > b->localid) return +1;
244 static struct ssh_channel *mainchan; /* primary session channel */
247 SSH_STATE_BEFORE_SIZE,
251 } ssh_state = SSH_STATE_BEFORE_SIZE;
253 static int size_needed = FALSE;
255 static void s_write (char *buf, int len) {
257 int i = send (s, buf, len, 0);
260 bombout(("Lost connection while sending"));
268 static int s_read (char *buf, int len) {
271 int i = recv (s, buf, len, 0);
274 len -= i, buf += i, ret += i;
281 static void c_write (char *buf, int len) {
282 if ((flags & FLAG_STDERR)) {
284 for (i = 0; i < len; i++)
286 fputc(buf[i], stderr);
293 static void c_writedata (char *buf, int len) {
307 static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
308 static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
310 static int ssh_version;
311 static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
312 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
313 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
314 static void ssh_size(void);
316 static int (*s_rdpkt)(unsigned char **data, int *datalen);
319 * Collect incoming data in the incoming packet buffer.
320 * Decipher and verify the packet when it is completely read.
321 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
322 * Update the *data and *datalen variables.
323 * Return the additional nr of bytes needed, or 0 when
324 * a complete packet is available.
326 static int ssh1_rdpkt(unsigned char **data, int *datalen)
328 static long len, pad, biglen, to_read;
329 static unsigned long realcrc, gotcrc;
330 static unsigned char *p;
340 for (i = len = 0; i < 4; i++) {
341 while ((*datalen) == 0)
343 len = (len << 8) + **data;
344 (*data)++, (*datalen)--;
348 if (len == 0x52656d6f) { /* "Remo"te server has closed ... */
349 len = 0x300; /* big enough to carry to end */
355 pktin.length = len - 5;
357 if (pktin.maxlen < biglen) {
358 pktin.maxlen = biglen;
359 pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) :
360 realloc(pktin.data, biglen+APIEXTRA));
362 fatalbox("Out of memory");
367 while (to_read > 0) {
370 while ((*datalen) == 0)
372 if (chunk > (*datalen))
374 memcpy(p, *data, chunk);
382 cipher->decrypt(pktin.data, biglen);
384 pktin.type = pktin.data[pad];
385 pktin.body = pktin.data + pad + 1;
387 realcrc = crc32(pktin.data, biglen-4);
388 gotcrc = GET_32BIT(pktin.data+biglen-4);
389 if (gotcrc != realcrc) {
390 bombout(("Incorrect CRC received on packet"));
394 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
395 pktin.type == SSH1_SMSG_STDERR_DATA ||
396 pktin.type == SSH1_MSG_DEBUG ||
397 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
398 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
399 long strlen = GET_32BIT(pktin.body);
400 if (strlen + 4 != pktin.length) {
401 bombout(("Received data packet with bogus string length"));
406 if (pktin.type == SSH1_MSG_DEBUG) {
407 /* log debug message */
409 int strlen = GET_32BIT(pktin.body);
410 strcpy(buf, "Remote: ");
411 if (strlen > 70) strlen = 70;
412 memcpy(buf+8, pktin.body+4, strlen);
413 buf[8+strlen] = '\0';
416 } else if (pktin.type == SSH1_MSG_IGNORE) {
424 static int ssh2_rdpkt(unsigned char **data, int *datalen)
426 static long len, pad, payload, packetlen, maclen;
428 static int cipherblk;
429 static unsigned long incoming_sequence = 0;
439 cipherblk = cipher->blksize;
445 if (pktin.maxlen < cipherblk) {
446 pktin.maxlen = cipherblk;
447 pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) :
448 realloc(pktin.data, cipherblk+APIEXTRA));
450 fatalbox("Out of memory");
454 * Acquire and decrypt the first block of the packet. This will
455 * contain the length and padding details.
457 for (i = len = 0; i < cipherblk; i++) {
458 while ((*datalen) == 0)
459 crReturn(cipherblk-i);
460 pktin.data[i] = *(*data)++;
464 if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
469 sccipher->decrypt(pktin.data, cipherblk);
472 * Now get the length and padding figures.
474 len = GET_32BIT(pktin.data);
478 * This enables us to deduce the payload length.
480 payload = len - pad - 1;
482 pktin.length = payload + 5;
485 * So now we can work out the total packet length.
488 maclen = scmac ? scmac->len : 0;
491 * Adjust memory allocation if packet is too big.
493 if (pktin.maxlen < packetlen+maclen) {
494 pktin.maxlen = packetlen+maclen;
495 pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
496 realloc(pktin.data, pktin.maxlen+APIEXTRA));
498 fatalbox("Out of memory");
502 * Read and decrypt the remainder of the packet.
504 for (i = cipherblk; i < packetlen + maclen; i++) {
505 while ((*datalen) == 0)
506 crReturn(packetlen + maclen - i);
507 pktin.data[i] = *(*data)++;
510 /* Decrypt everything _except_ the MAC. */
512 sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk);
515 debug(("Got packet len=%d pad=%d\r\n", len, pad));
516 for (i = 0; i < packetlen; i++)
517 debug((" %02x", (unsigned char)pktin.data[i]));
524 if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) {
525 bombout(("Incorrect MAC received on packet"));
528 incoming_sequence++; /* whether or not we MACed */
531 pktin.type = pktin.data[5];
533 if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
534 goto next_packet; /* FIXME: print DEBUG message */
539 static void ssh_gotdata(unsigned char *data, int datalen)
541 while (datalen > 0) {
542 if ( s_rdpkt(&data, &datalen) == 0 ) {
543 ssh_protocol(NULL, 0, 1);
544 if (ssh_state == SSH_STATE_CLOSED) {
552 static void s_wrpkt_start(int type, int len) {
555 len += 5; /* type and CRC */
559 pktout.length = len-5;
560 if (pktout.maxlen < biglen) {
561 pktout.maxlen = biglen;
563 /* Allocate enough buffer space for extra block
564 * for MS CryptEncrypt() */
565 pktout.data = (pktout.data == NULL ? malloc(biglen+12) :
566 realloc(pktout.data, biglen+12));
568 pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
569 realloc(pktout.data, biglen+4));
572 fatalbox("Out of memory");
576 pktout.body = pktout.data+4+pad+1;
579 static void s_wrpkt(void) {
580 int pad, len, biglen, i;
583 len = pktout.length + 5; /* type and CRC */
587 pktout.body[-1] = pktout.type;
588 for (i=0; i<pad; i++)
589 pktout.data[i+4] = random_byte();
590 crc = crc32(pktout.data+4, biglen-4);
591 PUT_32BIT(pktout.data+biglen, crc);
592 PUT_32BIT(pktout.data, len);
595 cipher->encrypt(pktout.data+4, biglen);
597 s_write(pktout.data, biglen+4);
601 * Construct a packet with the specified contents and
602 * send it to the server.
604 static void send_packet(int pkttype, ...)
607 unsigned char *p, *argp, argchar;
608 unsigned long argint;
609 int pktlen, argtype, arglen;
613 va_start(args, pkttype);
614 while ((argtype = va_arg(args, int)) != PKT_END) {
617 (void) va_arg(args, int);
621 (void) va_arg(args, char);
625 (void) va_arg(args, unsigned char *);
626 arglen = va_arg(args, int);
630 argp = va_arg(args, unsigned char *);
631 arglen = strlen(argp);
632 pktlen += 4 + arglen;
635 bn = va_arg(args, Bignum);
636 pktlen += ssh1_bignum_length(bn);
644 s_wrpkt_start(pkttype, pktlen);
647 va_start(args, pkttype);
648 while ((argtype = va_arg(args, int)) != PKT_END) {
651 argint = va_arg(args, int);
652 PUT_32BIT(p, argint);
656 argchar = va_arg(args, unsigned char);
661 argp = va_arg(args, unsigned char *);
662 arglen = va_arg(args, int);
663 memcpy(p, argp, arglen);
667 argp = va_arg(args, unsigned char *);
668 arglen = strlen(argp);
669 PUT_32BIT(p, arglen);
670 memcpy(p + 4, argp, arglen);
674 bn = va_arg(args, Bignum);
675 p += ssh1_write_bignum(p, bn);
686 * Connect to specified host and port.
687 * Returns an error message, or NULL on success.
688 * Also places the canonical host name into `realhost'.
690 static char *connect_to_host(char *host, int port, char **realhost)
700 savedhost = malloc(1+strlen(host));
702 fatalbox("Out of memory");
703 strcpy(savedhost, host);
706 port = 22; /* default ssh port */
718 if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
719 if ( (h = gethostbyname(host)) == NULL)
720 switch (WSAGetLastError()) {
721 case WSAENETDOWN: return "Network is down";
722 case WSAHOST_NOT_FOUND: case WSANO_DATA:
723 return "Host does not exist";
724 case WSATRY_AGAIN: return "Host not found";
725 default: return "gethostbyname: unknown error";
727 memcpy (&a, h->h_addr, sizeof(a));
728 *realhost = h->h_name;
739 s = socket(AF_INET, SOCK_STREAM, 0);
740 if (s == INVALID_SOCKET)
741 switch (WSAGetLastError()) {
742 case WSAENETDOWN: return "Network is down";
743 case WSAEAFNOSUPPORT: return "TCP/IP support not present";
744 default: return "socket(): unknown error";
748 * Bind to local address.
750 addr.sin_family = AF_INET;
751 addr.sin_addr.s_addr = htonl(INADDR_ANY);
752 addr.sin_port = htons(0);
753 if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
754 switch (WSAGetLastError()) {
755 case WSAENETDOWN: return "Network is down";
756 default: return "bind(): unknown error";
760 * Connect to remote address.
762 addr.sin_addr.s_addr = htonl(a);
763 addr.sin_port = htons((short)port);
764 if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
765 switch (WSAGetLastError()) {
766 case WSAENETDOWN: return "Network is down";
767 case WSAECONNREFUSED: return "Connection refused";
768 case WSAENETUNREACH: return "Network is unreachable";
769 case WSAEHOSTUNREACH: return "No route to host";
770 default: return "connect(): unknown error";
774 send(s, "connect ", 8, 0);
775 send(s, FWhost, strlen(FWhost), 0);
778 sprintf(buf, " %d\n", FWport);
779 send (s, buf, strlen(buf), 0);
786 static int ssh_versioncmp(char *a, char *b) {
788 unsigned long av, bv;
790 av = strtoul(a, &ae, 10);
791 bv = strtoul(b, &be, 10);
792 if (av != bv) return (av < bv ? -1 : +1);
793 if (*ae == '.') ae++;
794 if (*be == '.') be++;
795 av = strtoul(ae, &ae, 10);
796 bv = strtoul(be, &be, 10);
797 if (av != bv) return (av < bv ? -1 : +1);
803 * Utility routine for putting an SSH-protocol `string' into a SHA
807 void sha_string(SHA_State *s, void *str, int len) {
808 unsigned char lenblk[4];
809 PUT_32BIT(lenblk, len);
810 SHA_Bytes(s, lenblk, 4);
811 SHA_Bytes(s, str, len);
815 * SSH2 packet construction functions.
817 void ssh2_pkt_adddata(void *data, int len) {
818 pktout.length += len;
819 if (pktout.maxlen < pktout.length) {
820 pktout.maxlen = pktout.length + 256;
821 pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) :
822 realloc(pktout.data, pktout.maxlen+APIEXTRA));
824 fatalbox("Out of memory");
826 memcpy(pktout.data+pktout.length-len, data, len);
828 void ssh2_pkt_addbyte(unsigned char byte) {
829 ssh2_pkt_adddata(&byte, 1);
831 void ssh2_pkt_init(int pkt_type) {
833 ssh2_pkt_addbyte((unsigned char)pkt_type);
835 void ssh2_pkt_addbool(unsigned char value) {
836 ssh2_pkt_adddata(&value, 1);
838 void ssh2_pkt_adduint32(unsigned long value) {
841 ssh2_pkt_adddata(x, 4);
843 void ssh2_pkt_addstring_start(void) {
844 ssh2_pkt_adduint32(0);
845 pktout.savedpos = pktout.length;
847 void ssh2_pkt_addstring_str(char *data) {
848 ssh2_pkt_adddata(data, strlen(data));
849 PUT_32BIT(pktout.data + pktout.savedpos - 4,
850 pktout.length - pktout.savedpos);
852 void ssh2_pkt_addstring_data(char *data, int len) {
853 ssh2_pkt_adddata(data, len);
854 PUT_32BIT(pktout.data + pktout.savedpos - 4,
855 pktout.length - pktout.savedpos);
857 void ssh2_pkt_addstring(char *data) {
858 ssh2_pkt_addstring_start();
859 ssh2_pkt_addstring_str(data);
861 char *ssh2_mpint_fmt(Bignum b, int *len) {
864 p = malloc(n * 2 + 1);
866 fatalbox("out of memory");
868 for (i = 0; i < n; i++) {
869 p[i*2+1] = (b[n-i] >> 8) & 0xFF;
870 p[i*2+2] = (b[n-i] ) & 0xFF;
873 while (p[i] == 0 && (p[i+1] & 0x80) == 0)
875 memmove(p, p+i, n*2+1-i);
879 void ssh2_pkt_addmp(Bignum b) {
882 p = ssh2_mpint_fmt(b, &len);
883 ssh2_pkt_addstring_start();
884 ssh2_pkt_addstring_data(p, len);
887 void ssh2_pkt_send(void) {
888 int cipherblk, maclen, padding, i;
889 static unsigned long outgoing_sequence = 0;
892 * Add padding. At least four bytes, and must also bring total
893 * length (minus MAC) up to a multiple of the block size.
895 cipherblk = cipher ? cipher->blksize : 8; /* block size */
896 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
898 padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
899 pktout.data[4] = padding;
900 for (i = 0; i < padding; i++)
901 pktout.data[pktout.length + i] = random_byte();
902 PUT_32BIT(pktout.data, pktout.length + padding - 4);
904 csmac->generate(pktout.data, pktout.length + padding,
906 outgoing_sequence++; /* whether or not we MACed */
909 debug(("Sending packet len=%d\r\n", pktout.length+padding));
910 for (i = 0; i < pktout.length+padding; i++)
911 debug((" %02x", (unsigned char)pktout.data[i]));
916 cscipher->encrypt(pktout.data, pktout.length + padding);
917 maclen = csmac ? csmac->len : 0;
919 s_write(pktout.data, pktout.length + padding + maclen);
923 void bndebug(char *string, Bignum b) {
926 p = ssh2_mpint_fmt(b, &len);
927 debug(("%s", string));
928 for (i = 0; i < len; i++)
929 debug((" %02x", p[i]));
935 void sha_mpint(SHA_State *s, Bignum b) {
938 p = ssh2_mpint_fmt(b, &len);
939 sha_string(s, p, len);
944 * SSH2 packet decode functions.
946 unsigned long ssh2_pkt_getuint32(void) {
948 if (pktin.length - pktin.savedpos < 4)
949 return 0; /* arrgh, no way to decline (FIXME?) */
950 value = GET_32BIT(pktin.data+pktin.savedpos);
954 void ssh2_pkt_getstring(char **p, int *length) {
956 if (pktin.length - pktin.savedpos < 4)
958 *length = GET_32BIT(pktin.data+pktin.savedpos);
960 if (pktin.length - pktin.savedpos < *length)
962 *p = pktin.data+pktin.savedpos;
963 pktin.savedpos += *length;
965 Bignum ssh2_pkt_getmp(void) {
970 ssh2_pkt_getstring(&p, &length);
974 bombout(("internal error: Can't handle negative mpints"));
977 b = newbn((length+1)/2);
978 for (i = 0; i < length; i++) {
981 b[j/2+1] |= ((unsigned char)p[i]) << 8;
983 b[j/2+1] |= ((unsigned char)p[i]);
988 static int do_ssh_init(void) {
992 char vlog[sizeof(vstring)+20];
997 while (s_read(&c, 1) == 1) {
998 if (c == 'S' && i < 2) i++;
999 else if (c == 'S' && i == 2) i = 2;
1000 else if (c == 'H' && i == 2) break;
1004 if (s_read(&c,1) != 1 || c != 'S') return 0;
1005 if (s_read(&c,1) != 1 || c != 'S') return 0;
1006 if (s_read(&c,1) != 1 || c != 'H') return 0;
1008 strcpy(vstring, "SSH-");
1010 if (s_read(&c,1) != 1 || c != '-') return 0;
1013 if (s_read(&c,1) != 1)
1015 if (vsp < vstring+sizeof(vstring)-1)
1021 } else if (i < sizeof(version)-1)
1029 sprintf(vlog, "Server version: %s", vstring);
1030 vlog[strcspn(vlog, "\r\n")] = '\0';
1034 * Server version "1.99" means we can choose whether we use v1
1035 * or v2 protocol. Choice is based on cfg.sshprot.
1037 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
1039 * This is a v2 server. Begin v2 protocol.
1041 char *verstring = "SSH-2.0-PuTTY";
1044 * Hash our version string and their version string.
1046 sha_string(&exhash, verstring, strlen(verstring));
1047 sha_string(&exhash, vstring, strcspn(vstring, "\r\n"));
1048 sprintf(vstring, "%s\n", verstring);
1049 sprintf(vlog, "We claim version: %s", verstring);
1051 logevent("Using SSH protocol version 2");
1052 s_write(vstring, strlen(vstring));
1053 ssh_protocol = ssh2_protocol;
1055 s_rdpkt = ssh2_rdpkt;
1058 * This is a v1 server. Begin v1 protocol.
1060 sprintf(vstring, "SSH-%s-PuTTY\n",
1061 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
1062 sprintf(vlog, "We claim version: %s", vstring);
1063 vlog[strcspn(vlog, "\r\n")] = '\0';
1065 logevent("Using SSH protocol version 1");
1066 s_write(vstring, strlen(vstring));
1067 ssh_protocol = ssh1_protocol;
1069 s_rdpkt = ssh1_rdpkt;
1076 * Handle the key exchange and user authentication phases.
1078 static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
1081 unsigned char *rsabuf, *keystr1, *keystr2;
1082 unsigned char cookie[8];
1083 struct RSAKey servkey, hostkey;
1084 struct MD5Context md5c;
1085 static unsigned long supported_ciphers_mask, supported_auths_mask;
1086 static int tried_publickey;
1087 static unsigned char session_id[16];
1092 if (!ispkt) crWaitUntil(ispkt);
1094 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1095 bombout(("Public key packet not received"));
1099 logevent("Received public keys");
1101 memcpy(cookie, pktin.body, 8);
1103 i = makekey(pktin.body+8, &servkey, &keystr1, 0);
1104 j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
1107 * Log the host key fingerprint.
1111 logevent("Host key fingerprint is:");
1112 strcpy(logmsg, " ");
1113 hostkey.comment = NULL;
1114 rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg),
1119 supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
1120 supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
1123 MD5Update(&md5c, keystr2, hostkey.bytes);
1124 MD5Update(&md5c, keystr1, servkey.bytes);
1125 MD5Update(&md5c, pktin.body, 8);
1126 MD5Final(session_id, &md5c);
1128 for (i=0; i<32; i++)
1129 session_key[i] = random_byte();
1131 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
1133 rsabuf = malloc(len);
1135 fatalbox("Out of memory");
1138 * Verify the host key.
1142 * First format the key into a string.
1144 int len = rsastr_len(&hostkey);
1145 char *keystr = malloc(len);
1147 fatalbox("Out of memory");
1148 rsastr_fmt(keystr, &hostkey);
1149 verify_ssh_host_key(savedhost, keystr);
1153 for (i=0; i<32; i++) {
1154 rsabuf[i] = session_key[i];
1156 rsabuf[i] ^= session_id[i];
1159 if (hostkey.bytes > servkey.bytes) {
1160 rsaencrypt(rsabuf, 32, &servkey);
1161 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
1163 rsaencrypt(rsabuf, 32, &hostkey);
1164 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
1167 logevent("Encrypted session key");
1169 cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
1170 cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
1172 if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
1173 c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
1174 cipher_type = SSH_CIPHER_3DES;
1176 switch (cipher_type) {
1177 case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
1178 case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
1179 case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
1182 send_packet(SSH1_CMSG_SESSION_KEY,
1183 PKT_CHAR, cipher_type,
1184 PKT_DATA, cookie, 8,
1185 PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
1186 PKT_DATA, rsabuf, len,
1190 logevent("Trying to enable encryption...");
1194 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
1195 cipher_type == SSH_CIPHER_DES ? &ssh_des :
1197 cipher->sesskey(session_key);
1201 if (pktin.type != SSH1_SMSG_SUCCESS) {
1202 bombout(("Encryption not successfully enabled"));
1206 logevent("Successfully started encryption");
1210 static char username[100];
1213 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
1214 c_write("login as: ", 10);
1217 crWaitUntil(!ispkt);
1218 while (inlen--) switch (c = *in++) {
1225 c_write("\b \b", 3);
1231 c_write("\b \b", 3);
1240 if (((c >= ' ' && c <= '~') ||
1241 ((unsigned char)c >= 160)) && pos < 40) {
1242 username[pos++] = c;
1249 username[strcspn(username, "\n\r")] = '\0';
1252 strncpy(username, cfg.username, 99);
1253 username[99] = '\0';
1254 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
1255 sprintf(stuff, "Sent username \"%s\".\r\n", username);
1256 c_write(stuff, strlen(stuff));
1260 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
1262 char userlog[20+sizeof(username)];
1263 sprintf(userlog, "Sent username \"%s\"", username);
1270 tried_publickey = 0;
1272 while (pktin.type == SSH1_SMSG_FAILURE) {
1273 static char password[100];
1274 static char prompt[200];
1277 static int pwpkt_type;
1279 * Show password prompt, having first obtained it via a TIS
1280 * or CryptoCard exchange if we're doing TIS or CryptoCard
1283 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
1284 if (agent_exists()) {
1286 * Attempt RSA authentication using Pageant.
1288 static unsigned char request[5], *response, *p;
1289 static int responselen;
1290 static int i, nkeys;
1291 static int authed = FALSE;
1294 logevent("Pageant is running. Requesting keys.");
1296 /* Request the keys held by the agent. */
1297 PUT_32BIT(request, 1);
1298 request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
1299 agent_query(request, 5, &r, &responselen);
1300 response = (unsigned char *)r;
1303 nkeys = GET_32BIT(p); p += 4;
1304 { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
1306 for (i = 0; i < nkeys; i++) {
1307 static struct RSAKey key;
1308 static Bignum challenge;
1309 static char *commentp;
1310 static int commentlen;
1312 { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
1315 p += ssh1_read_bignum(p, &key.exponent);
1316 p += ssh1_read_bignum(p, &key.modulus);
1317 commentlen = GET_32BIT(p); p += 4;
1318 commentp = p; p += commentlen;
1319 send_packet(SSH1_CMSG_AUTH_RSA,
1320 PKT_BIGNUM, key.modulus, PKT_END);
1322 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1323 logevent("Key refused");
1326 logevent("Received RSA challenge");
1327 ssh1_read_bignum(pktin.body, &challenge);
1329 char *agentreq, *q, *ret;
1331 len = 1 + 4; /* message type, bit count */
1332 len += ssh1_bignum_length(key.exponent);
1333 len += ssh1_bignum_length(key.modulus);
1334 len += ssh1_bignum_length(challenge);
1335 len += 16; /* session id */
1336 len += 4; /* response format */
1337 agentreq = malloc(4 + len);
1338 PUT_32BIT(agentreq, len);
1340 *q++ = SSH_AGENTC_RSA_CHALLENGE;
1341 PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
1343 q += ssh1_write_bignum(q, key.exponent);
1344 q += ssh1_write_bignum(q, key.modulus);
1345 q += ssh1_write_bignum(q, challenge);
1346 memcpy(q, session_id, 16); q += 16;
1347 PUT_32BIT(q, 1); /* response format */
1348 agent_query(agentreq, len+4, &ret, &retlen);
1351 if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
1352 logevent("Sending Pageant's response");
1353 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1354 PKT_DATA, ret+5, 16, PKT_END);
1357 if (pktin.type == SSH1_SMSG_SUCCESS) {
1358 logevent("Pageant's response accepted");
1359 if (flags & FLAG_VERBOSE) {
1360 c_write("Authenticated using RSA key \"",
1362 c_write(commentp, commentlen);
1363 c_write("\" from agent\r\n", 14);
1367 logevent("Pageant's response not accepted");
1369 logevent("Pageant failed to answer challenge");
1373 logevent("No reply received from Pageant");
1376 freebn(key.exponent);
1377 freebn(key.modulus);
1386 if (*cfg.keyfile && !tried_publickey)
1387 pwpkt_type = SSH1_CMSG_AUTH_RSA;
1389 if (pktin.type == SSH1_SMSG_FAILURE &&
1391 (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
1392 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
1393 logevent("Requested TIS authentication");
1394 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
1396 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
1397 logevent("TIS authentication declined");
1398 if (flags & FLAG_INTERACTIVE)
1399 c_write("TIS authentication refused.\r\n", 29);
1401 int challengelen = ((pktin.body[0] << 24) |
1402 (pktin.body[1] << 16) |
1403 (pktin.body[2] << 8) |
1405 logevent("Received TIS challenge");
1406 if (challengelen > sizeof(prompt)-1)
1407 challengelen = sizeof(prompt)-1; /* prevent overrun */
1408 memcpy(prompt, pktin.body+4, challengelen);
1409 prompt[challengelen] = '\0';
1412 if (pktin.type == SSH1_SMSG_FAILURE &&
1414 (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
1415 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
1416 logevent("Requested CryptoCard authentication");
1417 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
1419 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
1420 logevent("CryptoCard authentication declined");
1421 c_write("CryptoCard authentication refused.\r\n", 29);
1423 int challengelen = ((pktin.body[0] << 24) |
1424 (pktin.body[1] << 16) |
1425 (pktin.body[2] << 8) |
1427 logevent("Received CryptoCard challenge");
1428 if (challengelen > sizeof(prompt)-1)
1429 challengelen = sizeof(prompt)-1; /* prevent overrun */
1430 memcpy(prompt, pktin.body+4, challengelen);
1431 strncpy(prompt + challengelen, "\r\nResponse : ",
1432 sizeof(prompt)-challengelen);
1433 prompt[sizeof(prompt)-1] = '\0';
1436 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
1437 sprintf(prompt, "%.90s@%.90s's password: ",
1438 cfg.username, savedhost);
1440 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1441 char *comment = NULL;
1442 if (flags & FLAG_VERBOSE)
1443 c_write("Trying public key authentication.\r\n", 35);
1444 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
1445 if (flags & FLAG_VERBOSE)
1446 c_write("No passphrase required.\r\n", 25);
1449 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
1453 if (!(flags & FLAG_INTERACTIVE)) {
1454 if (!ssh_get_password(prompt, password, sizeof(password))) {
1456 * get_password failed to get a password (for
1457 * example because one was supplied on the command
1458 * line which has already failed to work).
1461 logevent("No more passwords to try");
1462 ssh_state = SSH_STATE_CLOSED;
1466 c_write(prompt, strlen(prompt));
1470 crWaitUntil(!ispkt);
1471 while (inlen--) switch (c = *in++) {
1488 if (((c >= ' ' && c <= '~') ||
1489 ((unsigned char)c >= 160)) && pos < sizeof(password))
1490 password[pos++] = c;
1498 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
1500 * Try public key authentication with the specified
1503 static struct RSAKey pubkey;
1504 static Bignum challenge, response;
1506 static unsigned char buffer[32];
1508 tried_publickey = 1;
1509 i = loadrsakey(cfg.keyfile, &pubkey, password);
1511 c_write("Couldn't load public key from ", 30);
1512 c_write(cfg.keyfile, strlen(cfg.keyfile));
1513 c_write(".\r\n", 3);
1514 continue; /* go and try password */
1517 c_write("Wrong passphrase.\r\n", 19);
1518 tried_publickey = 0;
1519 continue; /* try again */
1523 * Send a public key attempt.
1525 send_packet(SSH1_CMSG_AUTH_RSA,
1526 PKT_BIGNUM, pubkey.modulus, PKT_END);
1529 if (pktin.type == SSH1_SMSG_FAILURE) {
1530 c_write("Server refused our public key.\r\n", 32);
1531 continue; /* go and try password */
1533 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
1534 bombout(("Bizarre response to offer of public key"));
1537 ssh1_read_bignum(pktin.body, &challenge);
1538 response = rsadecrypt(challenge, &pubkey);
1539 freebn(pubkey.private_exponent); /* burn the evidence */
1541 for (i = 0; i < 32; i += 2) {
1542 buffer[i] = response[16-i/2] >> 8;
1543 buffer[i+1] = response[16-i/2] & 0xFF;
1547 MD5Update(&md5c, buffer, 32);
1548 MD5Update(&md5c, session_id, 16);
1549 MD5Final(buffer, &md5c);
1551 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
1552 PKT_DATA, buffer, 16, PKT_END);
1555 if (pktin.type == SSH1_SMSG_FAILURE) {
1556 if (flags & FLAG_VERBOSE)
1557 c_write("Failed to authenticate with our public key.\r\n",
1559 continue; /* go and try password */
1560 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1561 bombout(("Bizarre response to RSA authentication response"));
1565 break; /* we're through! */
1567 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
1569 logevent("Sent password");
1570 memset(password, 0, strlen(password));
1572 if (pktin.type == SSH1_SMSG_FAILURE) {
1573 if (flags & FLAG_VERBOSE)
1574 c_write("Access denied\r\n", 15);
1575 logevent("Authentication refused");
1576 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1577 logevent("Received disconnect request");
1578 ssh_state = SSH_STATE_CLOSED;
1580 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
1581 bombout(("Strange packet received, type %d", pktin.type));
1586 logevent("Authentication successful");
1591 static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
1596 while (!do_ssh1_login(in, inlen, ispkt)) {
1599 if (ssh_state == SSH_STATE_CLOSED)
1602 if (cfg.agentfwd && agent_exists()) {
1603 logevent("Requesting agent forwarding");
1604 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
1605 do { crReturnV; } while (!ispkt);
1606 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1607 bombout(("Protocol confusion"));
1609 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1610 logevent("Agent forwarding refused");
1612 logevent("Agent forwarding enabled");
1616 send_packet(SSH1_CMSG_REQUEST_PTY,
1617 PKT_STR, cfg.termtype,
1618 PKT_INT, rows, PKT_INT, cols,
1619 PKT_INT, 0, PKT_INT, 0,
1622 ssh_state = SSH_STATE_INTERMED;
1623 do { crReturnV; } while (!ispkt);
1624 if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
1625 bombout(("Protocol confusion"));
1627 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1628 c_write("Server refused to allocate pty\r\n", 32);
1630 logevent("Allocated pty");
1633 if (*cfg.remote_cmd)
1634 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
1636 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
1637 logevent("Started session");
1639 ssh_state = SSH_STATE_SESSION;
1644 ssh_channels = newtree234(ssh_channelcmp);
1649 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
1650 pktin.type == SSH1_SMSG_STDERR_DATA) {
1651 long len = GET_32BIT(pktin.body);
1652 c_writedata(pktin.body+4, len);
1653 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
1654 ssh_state = SSH_STATE_CLOSED;
1655 logevent("Received disconnect request");
1656 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
1657 /* Remote side is trying to open a channel to talk to our
1658 * agent. Give them back a local channel number. */
1660 struct ssh_channel *c;
1662 for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
1664 break; /* found a free number */
1667 c = malloc(sizeof(struct ssh_channel));
1668 c->remoteid = GET_32BIT(pktin.body);
1671 c->type = SSH1_SMSG_AGENT_OPEN; /* identify channel type */
1672 c->u.a.lensofar = 0;
1673 add234(ssh_channels, c);
1674 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
1675 PKT_INT, c->remoteid, PKT_INT, c->localid,
1677 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
1678 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
1679 /* Remote side closes a channel. */
1680 unsigned i = GET_32BIT(pktin.body);
1681 struct ssh_channel *c;
1682 c = find234(ssh_channels, &i, ssh_channelfind);
1685 closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
1686 send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
1687 c->closes |= closetype;
1688 if (c->closes == 3) {
1689 del234(ssh_channels, c);
1693 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
1694 /* Data sent down one of our channels. */
1695 int i = GET_32BIT(pktin.body);
1696 int len = GET_32BIT(pktin.body+4);
1697 unsigned char *p = pktin.body+8;
1698 struct ssh_channel *c;
1699 c = find234(ssh_channels, &i, ssh_channelfind);
1702 case SSH1_SMSG_AGENT_OPEN:
1703 /* Data for an agent message. Buffer it. */
1705 if (c->u.a.lensofar < 4) {
1706 int l = min(4 - c->u.a.lensofar, len);
1707 memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
1708 p += l; len -= l; c->u.a.lensofar += l;
1710 if (c->u.a.lensofar == 4) {
1711 c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
1712 c->u.a.message = malloc(c->u.a.totallen);
1713 memcpy(c->u.a.message, c->u.a.msglen, 4);
1715 if (c->u.a.lensofar >= 4 && len > 0) {
1716 int l = min(c->u.a.totallen - c->u.a.lensofar, len);
1717 memcpy(c->u.a.message + c->u.a.lensofar, p, l);
1718 p += l; len -= l; c->u.a.lensofar += l;
1720 if (c->u.a.lensofar == c->u.a.totallen) {
1721 void *reply, *sentreply;
1723 agent_query(c->u.a.message, c->u.a.totallen,
1728 /* Fake SSH_AGENT_FAILURE. */
1729 sentreply = "\0\0\0\1\5";
1732 send_packet(SSH1_MSG_CHANNEL_DATA,
1733 PKT_INT, c->remoteid,
1735 PKT_DATA, sentreply, replylen,
1739 free(c->u.a.message);
1740 c->u.a.lensofar = 0;
1746 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
1747 /* may be from EXEC_SHELL on some servers */
1748 } else if (pktin.type == SSH1_SMSG_FAILURE) {
1749 /* may be from EXEC_SHELL on some servers
1750 * if no pty is available or in other odd cases. Ignore */
1751 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
1752 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
1754 bombout(("Strange packet received: type %d", pktin.type));
1758 send_packet(SSH1_CMSG_STDIN_DATA,
1759 PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END);
1767 * Utility routine for decoding comma-separated strings in KEXINIT.
1769 int in_commasep_string(char *needle, char *haystack, int haylen) {
1770 int needlen = strlen(needle);
1773 * Is it at the start of the string?
1775 if (haylen >= needlen && /* haystack is long enough */
1776 !memcmp(needle, haystack, needlen) && /* initial match */
1777 (haylen == needlen || haystack[needlen] == ',')
1778 /* either , or EOS follows */
1782 * If not, search for the next comma and resume after that.
1783 * If no comma found, terminate.
1785 while (haylen > 0 && *haystack != ',')
1786 haylen--, haystack++;
1789 haylen--, haystack++; /* skip over comma itself */
1794 * SSH2 key creation method.
1796 void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
1798 /* First 20 bytes. */
1801 SHA_Bytes(&s, H, 20);
1802 SHA_Bytes(&s, &chr, 1);
1803 SHA_Bytes(&s, H, 20);
1804 SHA_Final(&s, keyspace);
1805 /* Next 20 bytes. */
1808 SHA_Bytes(&s, H, 20);
1809 SHA_Bytes(&s, keyspace, 20);
1810 SHA_Final(&s, keyspace+20);
1814 * Handle the SSH2 transport layer.
1816 static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
1820 static Bignum e, f, K;
1821 static struct ssh_cipher *cscipher_tobe = NULL;
1822 static struct ssh_cipher *sccipher_tobe = NULL;
1823 static struct ssh_mac *csmac_tobe = NULL;
1824 static struct ssh_mac *scmac_tobe = NULL;
1825 static struct ssh_compress *cscomp_tobe = NULL;
1826 static struct ssh_compress *sccomp_tobe = NULL;
1827 static char *hostkeydata, *sigdata, *keystr;
1828 static int hostkeylen, siglen;
1829 static unsigned char exchange_hash[20];
1830 static unsigned char keyspace[40];
1836 * Set up the preferred cipher.
1838 if (cfg.cipher == CIPHER_BLOWFISH) {
1839 ciphers[0] = &ssh_blowfish_ssh2;
1840 } else if (cfg.cipher == CIPHER_DES) {
1841 logevent("Single DES not supported in SSH2; using 3DES");
1842 ciphers[0] = &ssh_3des_ssh2;
1843 } else if (cfg.cipher == CIPHER_3DES) {
1844 ciphers[0] = &ssh_3des_ssh2;
1846 /* Shouldn't happen, but we do want to initialise to _something_. */
1847 ciphers[0] = &ssh_3des_ssh2;
1852 * Construct and send our key exchange packet.
1854 ssh2_pkt_init(SSH2_MSG_KEXINIT);
1855 for (i = 0; i < 16; i++)
1856 ssh2_pkt_addbyte((unsigned char)random_byte());
1857 /* List key exchange algorithms. */
1858 ssh2_pkt_addstring_start();
1859 for (i = 0; i < lenof(kex_algs); i++) {
1860 ssh2_pkt_addstring_str(kex_algs[i]->name);
1861 if (i < lenof(kex_algs)-1)
1862 ssh2_pkt_addstring_str(",");
1864 /* List server host key algorithms. */
1865 ssh2_pkt_addstring_start();
1866 for (i = 0; i < lenof(hostkey_algs); i++) {
1867 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
1868 if (i < lenof(hostkey_algs)-1)
1869 ssh2_pkt_addstring_str(",");
1871 /* List client->server encryption algorithms. */
1872 ssh2_pkt_addstring_start();
1873 for (i = 0; i < lenof(ciphers); i++) {
1874 ssh2_pkt_addstring_str(ciphers[i]->name);
1875 if (i < lenof(ciphers)-1)
1876 ssh2_pkt_addstring_str(",");
1878 /* List server->client encryption algorithms. */
1879 ssh2_pkt_addstring_start();
1880 for (i = 0; i < lenof(ciphers); i++) {
1881 ssh2_pkt_addstring_str(ciphers[i]->name);
1882 if (i < lenof(ciphers)-1)
1883 ssh2_pkt_addstring_str(",");
1885 /* List client->server MAC algorithms. */
1886 ssh2_pkt_addstring_start();
1887 for (i = 0; i < lenof(macs); i++) {
1888 ssh2_pkt_addstring_str(macs[i]->name);
1889 if (i < lenof(macs)-1)
1890 ssh2_pkt_addstring_str(",");
1892 /* List server->client MAC algorithms. */
1893 ssh2_pkt_addstring_start();
1894 for (i = 0; i < lenof(macs); i++) {
1895 ssh2_pkt_addstring_str(macs[i]->name);
1896 if (i < lenof(macs)-1)
1897 ssh2_pkt_addstring_str(",");
1899 /* List client->server compression algorithms. */
1900 ssh2_pkt_addstring_start();
1901 for (i = 0; i < lenof(compressions); i++) {
1902 ssh2_pkt_addstring_str(compressions[i]->name);
1903 if (i < lenof(compressions)-1)
1904 ssh2_pkt_addstring_str(",");
1906 /* List server->client compression algorithms. */
1907 ssh2_pkt_addstring_start();
1908 for (i = 0; i < lenof(compressions); i++) {
1909 ssh2_pkt_addstring_str(compressions[i]->name);
1910 if (i < lenof(compressions)-1)
1911 ssh2_pkt_addstring_str(",");
1913 /* List client->server languages. Empty list. */
1914 ssh2_pkt_addstring_start();
1915 /* List server->client languages. Empty list. */
1916 ssh2_pkt_addstring_start();
1917 /* First KEX packet does _not_ follow, because we're not that brave. */
1918 ssh2_pkt_addbool(FALSE);
1920 ssh2_pkt_adduint32(0);
1921 sha_string(&exhash, pktout.data+5, pktout.length-5);
1924 if (!ispkt) crWaitUntil(ispkt);
1925 sha_string(&exhash, pktin.data+5, pktin.length-5);
1928 * Now examine the other side's KEXINIT to see what we're up
1931 if (pktin.type != SSH2_MSG_KEXINIT) {
1932 bombout(("expected key exchange packet from server"));
1935 kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
1936 csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
1937 pktin.savedpos += 16; /* skip garbage cookie */
1938 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
1939 for (i = 0; i < lenof(kex_algs); i++) {
1940 if (in_commasep_string(kex_algs[i]->name, str, len)) {
1945 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
1946 for (i = 0; i < lenof(hostkey_algs); i++) {
1947 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
1948 hostkey = hostkey_algs[i];
1952 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
1953 for (i = 0; i < lenof(ciphers); i++) {
1954 if (in_commasep_string(ciphers[i]->name, str, len)) {
1955 cscipher_tobe = ciphers[i];
1959 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
1960 for (i = 0; i < lenof(ciphers); i++) {
1961 if (in_commasep_string(ciphers[i]->name, str, len)) {
1962 sccipher_tobe = ciphers[i];
1966 ssh2_pkt_getstring(&str, &len); /* client->server mac */
1967 for (i = 0; i < lenof(macs); i++) {
1968 if (in_commasep_string(macs[i]->name, str, len)) {
1969 csmac_tobe = macs[i];
1973 ssh2_pkt_getstring(&str, &len); /* server->client mac */
1974 for (i = 0; i < lenof(macs); i++) {
1975 if (in_commasep_string(macs[i]->name, str, len)) {
1976 scmac_tobe = macs[i];
1980 ssh2_pkt_getstring(&str, &len); /* client->server compression */
1981 for (i = 0; i < lenof(compressions); i++) {
1982 if (in_commasep_string(compressions[i]->name, str, len)) {
1983 cscomp_tobe = compressions[i];
1987 ssh2_pkt_getstring(&str, &len); /* server->client compression */
1988 for (i = 0; i < lenof(compressions); i++) {
1989 if (in_commasep_string(compressions[i]->name, str, len)) {
1990 sccomp_tobe = compressions[i];
1996 * Currently we only support Diffie-Hellman and DSS, so let's
1997 * bomb out if those aren't selected.
1999 if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
2000 bombout(("internal fault: chaos in SSH 2 transport layer"));
2005 * Now we begin the fun. Generate and send e for Diffie-Hellman.
2008 ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
2013 if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
2014 bombout(("expected key exchange packet from server"));
2017 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
2018 f = ssh2_pkt_getmp();
2019 ssh2_pkt_getstring(&sigdata, &siglen);
2023 sha_string(&exhash, hostkeydata, hostkeylen);
2024 sha_mpint(&exhash, e);
2025 sha_mpint(&exhash, f);
2026 sha_mpint(&exhash, K);
2027 SHA_Final(&exhash, exchange_hash);
2030 debug(("Exchange hash is:\r\n"));
2031 for (i = 0; i < 20; i++)
2032 debug((" %02x", exchange_hash[i]));
2036 hostkey->setkey(hostkeydata, hostkeylen);
2037 if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) {
2038 bombout(("Server failed host key check"));
2043 * Expect SSH2_MSG_NEWKEYS from server.
2046 if (pktin.type != SSH2_MSG_NEWKEYS) {
2047 bombout(("expected new-keys packet from server"));
2052 * Authenticate remote host: verify host key. (We've already
2053 * checked the signature of the exchange hash.)
2055 keystr = hostkey->fmtkey();
2056 verify_ssh_host_key(savedhost, keystr);
2060 * Send SSH2_MSG_NEWKEYS.
2062 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
2066 * Create and initialise session keys.
2068 cscipher = cscipher_tobe;
2069 sccipher = sccipher_tobe;
2072 cscomp = cscomp_tobe;
2073 sccomp = sccomp_tobe;
2075 * Set IVs after keys.
2077 ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
2078 ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
2079 ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
2080 ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
2081 ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
2082 ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
2085 * Now we're encrypting. Begin returning 1 to the protocol main
2086 * function so that other things can run on top of the
2087 * transport. If we ever see a KEXINIT, we must go back to the
2092 } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
2093 goto begin_key_exchange;
2099 * Handle the SSH2 userauth and connection layers.
2101 static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
2103 static unsigned long remote_winsize;
2104 static unsigned long remote_maxpkt;
2109 * Request userauth protocol, and await a response to it.
2111 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
2112 ssh2_pkt_addstring("ssh-userauth");
2114 crWaitUntilV(ispkt);
2115 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
2116 bombout(("Server refused user authentication protocol"));
2121 * FIXME: currently we support only password authentication.
2122 * (This places us technically in violation of the SSH2 spec.
2123 * We must fix this.)
2127 * Get a username and a password.
2129 static char username[100];
2130 static char password[100];
2134 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
2135 c_write("login as: ", 10);
2138 crWaitUntilV(!ispkt);
2139 while (inlen--) switch (c = *in++) {
2146 c_write("\b \b", 3);
2152 c_write("\b \b", 3);
2161 if (((c >= ' ' && c <= '~') ||
2162 ((unsigned char)c >= 160)) && pos < 40) {
2163 username[pos++] = c;
2170 username[strcspn(username, "\n\r")] = '\0';
2173 strncpy(username, cfg.username, 99);
2174 username[99] = '\0';
2175 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
2176 sprintf(stuff, "Using username \"%s\".\r\n", username);
2177 c_write(stuff, strlen(stuff));
2181 if (!(flags & FLAG_INTERACTIVE)) {
2183 sprintf(prompt, "%.90s@%.90s's password: ", cfg.username, savedhost);
2184 if (!ssh_get_password(prompt, password, sizeof(password))) {
2186 * get_password failed to get a password (for
2187 * example because one was supplied on the command
2188 * line which has already failed to work).
2191 logevent("No more passwords to try");
2192 ssh_state = SSH_STATE_CLOSED;
2196 c_write("password: ", 10);
2201 crWaitUntilV(!ispkt);
2202 while (inlen--) switch (c = *in++) {
2219 if (((c >= ' ' && c <= '~') ||
2220 ((unsigned char)c >= 160)) && pos < 40)
2221 password[pos++] = c;
2228 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
2229 ssh2_pkt_addstring(username);
2230 ssh2_pkt_addstring("ssh-connection"); /* service requested */
2231 ssh2_pkt_addstring("password");
2232 ssh2_pkt_addbool(FALSE);
2233 ssh2_pkt_addstring(password);
2236 crWaitUntilV(ispkt);
2237 if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
2238 c_write("Access denied\r\n", 15);
2239 logevent("Authentication refused");
2245 * Now we're authenticated for the connection protocol. The
2246 * connection protocol will automatically have started at this
2247 * point; there's no need to send SERVICE_REQUEST.
2251 * So now create a channel with a session in it.
2253 mainchan = malloc(sizeof(struct ssh_channel));
2254 mainchan->localid = 100; /* as good as any */
2255 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
2256 ssh2_pkt_addstring("session");
2257 ssh2_pkt_adduint32(mainchan->localid);
2258 ssh2_pkt_adduint32(0x7FFFFFFFUL); /* our window size */
2259 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
2261 crWaitUntilV(ispkt);
2262 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
2263 bombout(("Server refused to open a session"));
2265 /* FIXME: error data comes back in FAILURE packet */
2267 if (ssh2_pkt_getuint32() != mainchan->localid) {
2268 bombout(("Server's channel confirmation cited wrong channel"));
2271 mainchan->remoteid = ssh2_pkt_getuint32();
2272 mainchan->u.v2.remwindow = ssh2_pkt_getuint32();
2273 mainchan->u.v2.remmaxpkt = ssh2_pkt_getuint32();
2274 mainchan->u.v2.outbuffer = NULL;
2275 mainchan->u.v2.outbuflen = mainchan->u.v2.outbufsize = 0;
2276 logevent("Opened channel for session");
2279 * Now allocate a pty for the session.
2282 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2283 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2284 ssh2_pkt_addstring("pty-req");
2285 ssh2_pkt_addbool(1); /* want reply */
2286 ssh2_pkt_addstring(cfg.termtype);
2287 ssh2_pkt_adduint32(cols);
2288 ssh2_pkt_adduint32(rows);
2289 ssh2_pkt_adduint32(0); /* pixel width */
2290 ssh2_pkt_adduint32(0); /* pixel height */
2291 ssh2_pkt_addstring_start();
2292 ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
2296 crWaitUntilV(ispkt);
2297 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2298 /* FIXME: be able to handle other channels here */
2299 if (ssh2_pkt_getuint32() != mainchan->localid)
2300 continue; /* wrong channel */
2301 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2303 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2305 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2306 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2307 bombout(("Server got confused by pty request"));
2310 c_write("Server refused to allocate pty\r\n", 32);
2312 logevent("Allocated pty");
2317 * Start a shell or a remote command.
2319 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
2320 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
2321 if (*cfg.remote_cmd) {
2322 ssh2_pkt_addstring("exec");
2323 ssh2_pkt_addbool(1); /* want reply */
2324 ssh2_pkt_addstring(cfg.remote_cmd);
2326 ssh2_pkt_addstring("shell");
2327 ssh2_pkt_addbool(1); /* want reply */
2331 crWaitUntilV(ispkt);
2332 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2333 /* FIXME: be able to handle other channels here */
2334 if (ssh2_pkt_getuint32() != mainchan->localid)
2335 continue; /* wrong channel */
2336 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2338 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2339 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
2340 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
2341 bombout(("Server got confused by shell/command request"));
2344 bombout(("Server refused to start a shell/command"));
2347 logevent("Started a shell/command");
2356 static int try_send;
2360 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
2361 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
2364 /* FIXME: be able to handle other channels here */
2365 if (ssh2_pkt_getuint32() != mainchan->localid)
2366 continue; /* wrong channel */
2367 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
2368 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
2369 continue; /* extended but not stderr */
2370 ssh2_pkt_getstring(&data, &length);
2372 c_writedata(data, length);
2374 * Enlarge the window again at the remote side,
2375 * just in case it ever runs down and they fail
2376 * to send us any more data.
2378 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2379 ssh2_pkt_adduint32(mainchan->remoteid);
2380 ssh2_pkt_adduint32(length);
2383 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
2384 ssh_state = SSH_STATE_CLOSED;
2385 logevent("Received disconnect message");
2386 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
2387 continue; /* exit status et al; ignore (FIXME?) */
2388 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
2389 continue; /* remote sends EOF; ignore */
2390 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
2391 /* FIXME: be able to handle other channels here */
2392 if (ssh2_pkt_getuint32() != mainchan->localid)
2393 continue; /* wrong channel */
2394 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2395 ssh2_pkt_adduint32(mainchan->remoteid);
2397 /* FIXME: mark the channel as closed */
2398 if (1 /* FIXME: "all channels are closed" */) {
2399 logevent("All channels closed. Disconnecting");
2400 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
2403 continue; /* remote sends close; ignore (FIXME) */
2404 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
2405 /* FIXME: be able to handle other channels here */
2406 if (ssh2_pkt_getuint32() != mainchan->localid)
2407 continue; /* wrong channel */
2408 mainchan->u.v2.remwindow += ssh2_pkt_getuint32();
2411 bombout(("Strange packet received: type %d", pktin.type));
2416 * We have spare data. Add it to the channel buffer.
2418 if (mainchan->u.v2.outbufsize <
2419 mainchan->u.v2.outbuflen + inlen) {
2420 mainchan->u.v2.outbufsize =
2421 mainchan->u.v2.outbuflen + inlen + 1024;
2422 mainchan->u.v2.outbuffer = srealloc(mainchan->u.v2.outbuffer,
2423 mainchan->u.v2.outbufsize);
2425 memcpy(mainchan->u.v2.outbuffer + mainchan->u.v2.outbuflen,
2427 mainchan->u.v2.outbuflen += inlen;
2432 * Try to send data on the channel if we can. (FIXME:
2433 * on _all_ channels.)
2435 while (mainchan->u.v2.remwindow > 0 &&
2436 mainchan->u.v2.outbuflen > 0) {
2437 unsigned len = mainchan->u.v2.remwindow;
2438 if (len > mainchan->u.v2.outbuflen)
2439 len = mainchan->u.v2.outbuflen;
2440 if (len > mainchan->u.v2.remmaxpkt)
2441 len = mainchan->u.v2.remmaxpkt;
2442 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
2443 ssh2_pkt_adduint32(mainchan->remoteid);
2444 ssh2_pkt_addstring_start();
2445 ssh2_pkt_addstring_data(mainchan->u.v2.outbuffer, len);
2447 mainchan->u.v2.outbuflen -= len;
2448 memmove(mainchan->u.v2.outbuffer, mainchan->u.v2.outbuffer+len,
2449 mainchan->u.v2.outbuflen);
2450 mainchan->u.v2.remwindow -= len;
2459 * Handle the top-level SSH2 protocol.
2461 static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
2463 if (do_ssh2_transport(in, inlen, ispkt) == 0)
2465 do_ssh2_authconn(in, inlen, ispkt);
2469 * Called to set up the connection. Will arrange for WM_NETEVENT
2470 * messages to be passed to the specified window, whose window
2471 * procedure should then call telnet_msg().
2473 * Returns an error message, or NULL on success.
2475 static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) {
2479 if(crypto_startup() == 0)
2480 return "Microsoft high encryption pack not installed!";
2483 p = connect_to_host(host, port, realhost);
2488 return "Protocol initialisation error";
2490 if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
2491 switch (WSAGetLastError()) {
2492 case WSAENETDOWN: return "Network is down";
2493 default: return "WSAAsyncSelect(): unknown error";
2500 * Process a WM_NETEVENT message. Will return 0 if the connection
2501 * has closed, or <0 for a socket error.
2503 static int ssh_msg (WPARAM wParam, LPARAM lParam) {
2508 * Because reading less than the whole of the available pending
2509 * data can generate an FD_READ event, we need to allow for the
2510 * possibility that FD_READ may arrive with FD_CLOSE already in
2511 * the queue; so it's possible that we can get here even with s
2512 * invalid. If so, we return 1 and don't worry about it.
2514 if (s == INVALID_SOCKET)
2517 if (WSAGETSELECTERROR(lParam) != 0) {
2520 return -WSAGETSELECTERROR(lParam);
2523 switch (WSAGETSELECTEVENT(lParam)) {
2526 ret = recv(s, buf, sizeof(buf), 0);
2527 if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
2529 if (ret < 0) { /* any _other_ error */
2532 return -10000-WSAGetLastError();
2538 ssh_gotdata (buf, ret);
2539 if (ssh_state == SSH_STATE_CLOSED) {
2546 return 1; /* shouldn't happen, but WTF */
2550 * Called to send data down the Telnet connection.
2552 static void ssh_send (char *buf, int len) {
2553 if (s == INVALID_SOCKET)
2556 ssh_protocol(buf, len, 0);
2560 * Called to set the size of the window from Telnet's POV.
2562 static void ssh_size(void) {
2563 switch (ssh_state) {
2564 case SSH_STATE_BEFORE_SIZE:
2565 case SSH_STATE_CLOSED:
2566 break; /* do nothing */
2567 case SSH_STATE_INTERMED:
2568 size_needed = TRUE; /* buffer for later */
2570 case SSH_STATE_SESSION:
2572 send_packet(SSH1_CMSG_WINDOW_SIZE,
2573 PKT_INT, rows, PKT_INT, cols,
2574 PKT_INT, 0, PKT_INT, 0, PKT_END);
2580 * Send Telnet special codes. TS_EOF is useful for `plink', so you
2581 * can send an EOF and collect resulting output (e.g. `plink
2584 static void ssh_special (Telnet_Special code) {
2585 if (code == TS_EOF) {
2586 if (ssh_version == 1) {
2587 send_packet(SSH1_CMSG_EOF, PKT_END);
2589 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
2590 ssh2_pkt_adduint32(mainchan->remoteid);
2593 logevent("Sent EOF message");
2599 static SOCKET ssh_socket(void) { return s; }
2601 static int ssh_sendok(void) { return ssh_send_ok; }
2603 Backend ssh_backend = {