| 1 | #include <stdio.h> |
| 2 | #include <stdlib.h> |
| 3 | #include <winsock.h> |
| 4 | |
| 5 | #include "putty.h" |
| 6 | |
| 7 | #ifndef FALSE |
| 8 | #define FALSE 0 |
| 9 | #endif |
| 10 | #ifndef TRUE |
| 11 | #define TRUE 1 |
| 12 | #endif |
| 13 | |
| 14 | #include "ssh.h" |
| 15 | |
| 16 | #define SSH_MSG_DISCONNECT 1 |
| 17 | #define SSH_SMSG_PUBLIC_KEY 2 |
| 18 | #define SSH_CMSG_SESSION_KEY 3 |
| 19 | #define SSH_CMSG_USER 4 |
| 20 | #define SSH_CMSG_AUTH_PASSWORD 9 |
| 21 | #define SSH_CMSG_REQUEST_PTY 10 |
| 22 | #define SSH_CMSG_EXEC_SHELL 12 |
| 23 | #define SSH_CMSG_STDIN_DATA 16 |
| 24 | #define SSH_SMSG_STDOUT_DATA 17 |
| 25 | #define SSH_SMSG_STDERR_DATA 18 |
| 26 | #define SSH_SMSG_SUCCESS 14 |
| 27 | #define SSH_SMSG_FAILURE 15 |
| 28 | #define SSH_SMSG_EXITSTATUS 20 |
| 29 | #define SSH_MSG_IGNORE 32 |
| 30 | #define SSH_CMSG_EXIT_CONFIRMATION 33 |
| 31 | #define SSH_MSG_DEBUG 36 |
| 32 | #define SSH_CMSG_AUTH_TIS 39 |
| 33 | #define SSH_SMSG_AUTH_TIS_CHALLENGE 40 |
| 34 | #define SSH_CMSG_AUTH_TIS_RESPONSE 41 |
| 35 | |
| 36 | #define SSH_AUTH_TIS 5 |
| 37 | |
| 38 | /* Coroutine mechanics for the sillier bits of the code */ |
| 39 | #define crBegin1 static int crLine = 0; |
| 40 | #define crBegin2 switch(crLine) { case 0:; |
| 41 | #define crBegin crBegin1; crBegin2; |
| 42 | #define crFinish(z) } crLine = 0; return (z) |
| 43 | #define crFinishV } crLine = 0; return |
| 44 | #define crReturn(z) \ |
| 45 | do {\ |
| 46 | crLine=__LINE__; return (z); case __LINE__:;\ |
| 47 | } while (0) |
| 48 | #define crReturnV \ |
| 49 | do {\ |
| 50 | crLine=__LINE__; return; case __LINE__:;\ |
| 51 | } while (0) |
| 52 | #define crStop(z) do{ crLine = 0; return (z); }while(0) |
| 53 | #define crStopV do{ crLine = 0; return; }while(0) |
| 54 | |
| 55 | #ifndef FALSE |
| 56 | #define FALSE 0 |
| 57 | #endif |
| 58 | #ifndef TRUE |
| 59 | #define TRUE 1 |
| 60 | #endif |
| 61 | |
| 62 | static SOCKET s = INVALID_SOCKET; |
| 63 | |
| 64 | static unsigned char session_key[32]; |
| 65 | static struct ssh_cipher *cipher = NULL; |
| 66 | |
| 67 | static char *savedhost; |
| 68 | |
| 69 | static enum { |
| 70 | SSH_STATE_BEFORE_SIZE, |
| 71 | SSH_STATE_INTERMED, |
| 72 | SSH_STATE_SESSION, |
| 73 | SSH_STATE_CLOSED |
| 74 | } ssh_state = SSH_STATE_BEFORE_SIZE; |
| 75 | |
| 76 | static int size_needed = FALSE; |
| 77 | |
| 78 | static void s_write (char *buf, int len) { |
| 79 | while (len > 0) { |
| 80 | int i = send (s, buf, len, 0); |
| 81 | if (i > 0) |
| 82 | len -= i, buf += i; |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | static int s_read (char *buf, int len) { |
| 87 | int ret = 0; |
| 88 | while (len > 0) { |
| 89 | int i = recv (s, buf, len, 0); |
| 90 | if (i > 0) |
| 91 | len -= i, buf += i, ret += i; |
| 92 | else |
| 93 | return i; |
| 94 | } |
| 95 | return ret; |
| 96 | } |
| 97 | |
| 98 | static void c_write (char *buf, int len) { |
| 99 | while (len--) { |
| 100 | int new_head = (inbuf_head + 1) & INBUF_MASK; |
| 101 | if (new_head != inbuf_reap) { |
| 102 | inbuf[inbuf_head] = *buf++; |
| 103 | inbuf_head = new_head; |
| 104 | } else { |
| 105 | term_out(); |
| 106 | if( inbuf_head == inbuf_reap ) len++; else break; |
| 107 | } |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | struct Packet { |
| 112 | long length; |
| 113 | int type; |
| 114 | unsigned long crc; |
| 115 | unsigned char *data; |
| 116 | unsigned char *body; |
| 117 | long maxlen; |
| 118 | }; |
| 119 | |
| 120 | static struct Packet pktin = { 0, 0, 0, NULL, 0 }; |
| 121 | static struct Packet pktout = { 0, 0, 0, NULL, 0 }; |
| 122 | |
| 123 | static void ssh_protocol(unsigned char *in, int inlen, int ispkt); |
| 124 | static void ssh_size(void); |
| 125 | |
| 126 | static void ssh_gotdata(unsigned char *data, int datalen) { |
| 127 | static long len, biglen, to_read; |
| 128 | static unsigned char *p; |
| 129 | static int i, pad; |
| 130 | |
| 131 | crBegin; |
| 132 | while (1) { |
| 133 | for (i = len = 0; i < 4; i++) { |
| 134 | while (datalen == 0) |
| 135 | crReturnV; |
| 136 | len = (len << 8) + *data; |
| 137 | data++, datalen--; |
| 138 | } |
| 139 | |
| 140 | #ifdef FWHACK |
| 141 | if (len == 0x52656d6f) { /* "Remo"te server has closed ... */ |
| 142 | len = 0x300; /* big enough to carry to end */ |
| 143 | } |
| 144 | #endif |
| 145 | |
| 146 | pad = 8 - (len%8); |
| 147 | |
| 148 | biglen = len + pad; |
| 149 | |
| 150 | len -= 5; /* type and CRC */ |
| 151 | |
| 152 | pktin.length = len; |
| 153 | if (pktin.maxlen < biglen) { |
| 154 | pktin.maxlen = biglen; |
| 155 | #ifdef MSCRYPTOAPI |
| 156 | /* Allocate enough buffer space for extra block |
| 157 | * for MS CryptEncrypt() */ |
| 158 | pktin.data = (pktin.data == NULL ? malloc(biglen+8) : |
| 159 | realloc(pktin.data, biglen+8)); |
| 160 | #else |
| 161 | pktin.data = (pktin.data == NULL ? malloc(biglen) : |
| 162 | realloc(pktin.data, biglen)); |
| 163 | #endif |
| 164 | if (!pktin.data) |
| 165 | fatalbox("Out of memory"); |
| 166 | } |
| 167 | |
| 168 | p = pktin.data, to_read = biglen; |
| 169 | while (to_read > 0) { |
| 170 | static int chunk; |
| 171 | chunk = to_read; |
| 172 | while (datalen == 0) |
| 173 | crReturnV; |
| 174 | if (chunk > datalen) |
| 175 | chunk = datalen; |
| 176 | memcpy(p, data, chunk); |
| 177 | data += chunk; |
| 178 | datalen -= chunk; |
| 179 | p += chunk; |
| 180 | to_read -= chunk; |
| 181 | } |
| 182 | |
| 183 | if (cipher) |
| 184 | cipher->decrypt(pktin.data, biglen); |
| 185 | |
| 186 | pktin.type = pktin.data[pad]; |
| 187 | pktin.body = pktin.data+pad+1; |
| 188 | |
| 189 | if (pktin.type == SSH_MSG_DEBUG) { |
| 190 | /* FIXME: log it */ |
| 191 | } else if (pktin.type == SSH_MSG_IGNORE) { |
| 192 | /* do nothing */; |
| 193 | } else |
| 194 | ssh_protocol(NULL, 0, 1); |
| 195 | } |
| 196 | crFinishV; |
| 197 | } |
| 198 | |
| 199 | static void s_wrpkt_start(int type, int len) { |
| 200 | int pad, biglen; |
| 201 | |
| 202 | len += 5; /* type and CRC */ |
| 203 | pad = 8 - (len%8); |
| 204 | biglen = len + pad; |
| 205 | |
| 206 | pktout.length = len-5; |
| 207 | if (pktout.maxlen < biglen) { |
| 208 | pktout.maxlen = biglen; |
| 209 | #ifdef MSCRYPTOAPI |
| 210 | /* Allocate enough buffer space for extra block |
| 211 | * for MS CryptEncrypt() */ |
| 212 | pktout.data = (pktout.data == NULL ? malloc(biglen+8) : |
| 213 | realloc(pktout.data, biglen+8)); |
| 214 | #else |
| 215 | pktout.data = (pktout.data == NULL ? malloc(biglen+4) : |
| 216 | realloc(pktout.data, biglen+4)); |
| 217 | #endif |
| 218 | if (!pktout.data) |
| 219 | fatalbox("Out of memory"); |
| 220 | } |
| 221 | |
| 222 | pktout.type = type; |
| 223 | pktout.body = pktout.data+4+pad+1; |
| 224 | } |
| 225 | |
| 226 | static void s_wrpkt(void) { |
| 227 | int pad, len, biglen, i; |
| 228 | unsigned long crc; |
| 229 | |
| 230 | len = pktout.length + 5; /* type and CRC */ |
| 231 | pad = 8 - (len%8); |
| 232 | biglen = len + pad; |
| 233 | |
| 234 | pktout.body[-1] = pktout.type; |
| 235 | for (i=0; i<pad; i++) |
| 236 | pktout.data[i+4] = random_byte(); |
| 237 | crc = crc32(pktout.data+4, biglen-4); |
| 238 | |
| 239 | pktout.data[biglen+0] = (unsigned char) ((crc >> 24) & 0xFF); |
| 240 | pktout.data[biglen+1] = (unsigned char) ((crc >> 16) & 0xFF); |
| 241 | pktout.data[biglen+2] = (unsigned char) ((crc >> 8) & 0xFF); |
| 242 | pktout.data[biglen+3] = (unsigned char) (crc & 0xFF); |
| 243 | |
| 244 | pktout.data[0] = (len >> 24) & 0xFF; |
| 245 | pktout.data[1] = (len >> 16) & 0xFF; |
| 246 | pktout.data[2] = (len >> 8) & 0xFF; |
| 247 | pktout.data[3] = len & 0xFF; |
| 248 | |
| 249 | if (cipher) |
| 250 | cipher->encrypt(pktout.data+4, biglen); |
| 251 | |
| 252 | s_write(pktout.data, biglen+4); |
| 253 | } |
| 254 | |
| 255 | static int ssh_versioncmp(char *a, char *b) { |
| 256 | char *ae, *be; |
| 257 | unsigned long av, bv; |
| 258 | |
| 259 | av = strtoul(a, &ae, 10); |
| 260 | bv = strtoul(b, &be, 10); |
| 261 | if (av != bv) return (av < bv ? -1 : +1); |
| 262 | if (*ae == '.') ae++; |
| 263 | if (*be == '.') be++; |
| 264 | av = strtoul(ae, &ae, 10); |
| 265 | bv = strtoul(be, &be, 10); |
| 266 | if (av != bv) return (av < bv ? -1 : +1); |
| 267 | return 0; |
| 268 | } |
| 269 | |
| 270 | static int do_ssh_init(void) { |
| 271 | char c, *vsp; |
| 272 | char version[10]; |
| 273 | char vstring[80]; |
| 274 | char vlog[sizeof(vstring)+20]; |
| 275 | int i; |
| 276 | |
| 277 | #ifdef FWHACK |
| 278 | i = 0; |
| 279 | while (s_read(&c, 1) == 1) { |
| 280 | if (c == 'S' && i < 2) i++; |
| 281 | else if (c == 'S' && i == 2) i = 2; |
| 282 | else if (c == 'H' && i == 2) break; |
| 283 | else i = 0; |
| 284 | } |
| 285 | #else |
| 286 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
| 287 | if (s_read(&c,1) != 1 || c != 'S') return 0; |
| 288 | if (s_read(&c,1) != 1 || c != 'H') return 0; |
| 289 | #endif |
| 290 | strcpy(vstring, "SSH-"); |
| 291 | vsp = vstring+4; |
| 292 | if (s_read(&c,1) != 1 || c != '-') return 0; |
| 293 | i = 0; |
| 294 | while (1) { |
| 295 | if (s_read(&c,1) != 1) |
| 296 | return 0; |
| 297 | if (vsp < vstring+sizeof(vstring)-1) |
| 298 | *vsp++ = c; |
| 299 | if (i >= 0) { |
| 300 | if (c == '-') { |
| 301 | version[i] = '\0'; |
| 302 | i = -1; |
| 303 | } else if (i < sizeof(version)-1) |
| 304 | version[i++] = c; |
| 305 | } |
| 306 | else if (c == '\n') |
| 307 | break; |
| 308 | } |
| 309 | |
| 310 | *vsp = 0; |
| 311 | sprintf(vlog, "Server version: %s", vstring); |
| 312 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
| 313 | logevent(vlog); |
| 314 | |
| 315 | sprintf(vstring, "SSH-%s-PuTTY\n", |
| 316 | (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5")); |
| 317 | sprintf(vlog, "We claim version: %s", vstring); |
| 318 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
| 319 | logevent(vlog); |
| 320 | s_write(vstring, strlen(vstring)); |
| 321 | return 1; |
| 322 | } |
| 323 | |
| 324 | static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { |
| 325 | int i, j, len; |
| 326 | unsigned char session_id[16]; |
| 327 | unsigned char *rsabuf, *keystr1, *keystr2; |
| 328 | unsigned char cookie[8]; |
| 329 | struct RSAKey servkey, hostkey; |
| 330 | struct MD5Context md5c; |
| 331 | static unsigned long supported_ciphers_mask, supported_auths_mask; |
| 332 | int cipher_type; |
| 333 | |
| 334 | extern struct ssh_cipher ssh_3des; |
| 335 | extern struct ssh_cipher ssh_des; |
| 336 | extern struct ssh_cipher ssh_blowfish; |
| 337 | |
| 338 | crBegin; |
| 339 | |
| 340 | random_init(); |
| 341 | |
| 342 | while (!ispkt) |
| 343 | crReturnV; |
| 344 | |
| 345 | if (pktin.type != SSH_SMSG_PUBLIC_KEY) |
| 346 | fatalbox("Public key packet not received"); |
| 347 | |
| 348 | logevent("Received public keys"); |
| 349 | |
| 350 | memcpy(cookie, pktin.body, 8); |
| 351 | |
| 352 | i = makekey(pktin.body+8, &servkey, &keystr1); |
| 353 | |
| 354 | j = makekey(pktin.body+8+i, &hostkey, &keystr2); |
| 355 | |
| 356 | /* |
| 357 | * Hash the host key and print the hash in the log box. Just as |
| 358 | * a last resort in case the registry's host key checking is |
| 359 | * compromised, we'll allow the user some ability to verify |
| 360 | * host keys by eye. |
| 361 | */ |
| 362 | MD5Init(&md5c); |
| 363 | MD5Update(&md5c, keystr2, hostkey.bytes); |
| 364 | MD5Final(session_id, &md5c); |
| 365 | { |
| 366 | char logmsg[80]; |
| 367 | int i; |
| 368 | logevent("Host key MD5 is:"); |
| 369 | strcpy(logmsg, " "); |
| 370 | for (i = 0; i < 16; i++) |
| 371 | sprintf(logmsg+strlen(logmsg), "%02x", session_id[i]); |
| 372 | logevent(logmsg); |
| 373 | } |
| 374 | |
| 375 | supported_ciphers_mask = ((pktin.body[12+i+j] << 24) | |
| 376 | (pktin.body[13+i+j] << 16) | |
| 377 | (pktin.body[14+i+j] << 8) | |
| 378 | (pktin.body[15+i+j])); |
| 379 | |
| 380 | supported_auths_mask = ((pktin.body[16+i+j] << 24) | |
| 381 | (pktin.body[17+i+j] << 16) | |
| 382 | (pktin.body[18+i+j] << 8) | |
| 383 | (pktin.body[19+i+j])); |
| 384 | |
| 385 | MD5Init(&md5c); |
| 386 | |
| 387 | MD5Update(&md5c, keystr2, hostkey.bytes); |
| 388 | MD5Update(&md5c, keystr1, servkey.bytes); |
| 389 | MD5Update(&md5c, pktin.body, 8); |
| 390 | |
| 391 | MD5Final(session_id, &md5c); |
| 392 | |
| 393 | for (i=0; i<32; i++) |
| 394 | session_key[i] = random_byte(); |
| 395 | |
| 396 | len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes); |
| 397 | |
| 398 | rsabuf = malloc(len); |
| 399 | if (!rsabuf) |
| 400 | fatalbox("Out of memory"); |
| 401 | |
| 402 | /* |
| 403 | * Verify the host key. |
| 404 | */ |
| 405 | { |
| 406 | /* |
| 407 | * First format the key into a string. |
| 408 | */ |
| 409 | int len = rsastr_len(&hostkey); |
| 410 | char *keystr = malloc(len); |
| 411 | if (!keystr) |
| 412 | fatalbox("Out of memory"); |
| 413 | rsastr_fmt(keystr, &hostkey); |
| 414 | verify_ssh_host_key(savedhost, keystr); |
| 415 | free(keystr); |
| 416 | } |
| 417 | |
| 418 | for (i=0; i<32; i++) { |
| 419 | rsabuf[i] = session_key[i]; |
| 420 | if (i < 16) |
| 421 | rsabuf[i] ^= session_id[i]; |
| 422 | } |
| 423 | |
| 424 | if (hostkey.bytes > servkey.bytes) { |
| 425 | rsaencrypt(rsabuf, 32, &servkey); |
| 426 | rsaencrypt(rsabuf, servkey.bytes, &hostkey); |
| 427 | } else { |
| 428 | rsaencrypt(rsabuf, 32, &hostkey); |
| 429 | rsaencrypt(rsabuf, hostkey.bytes, &servkey); |
| 430 | } |
| 431 | |
| 432 | logevent("Encrypted session key"); |
| 433 | |
| 434 | cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH : |
| 435 | cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES : |
| 436 | SSH_CIPHER_3DES; |
| 437 | if ((supported_ciphers_mask & (1 << cipher_type)) == 0) { |
| 438 | c_write("Selected cipher not supported, falling back to 3DES\r\n", 53); |
| 439 | cipher_type = SSH_CIPHER_3DES; |
| 440 | } |
| 441 | switch (cipher_type) { |
| 442 | case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break; |
| 443 | case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break; |
| 444 | case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break; |
| 445 | } |
| 446 | |
| 447 | s_wrpkt_start(SSH_CMSG_SESSION_KEY, len+15); |
| 448 | pktout.body[0] = cipher_type; |
| 449 | memcpy(pktout.body+1, cookie, 8); |
| 450 | pktout.body[9] = (len*8) >> 8; |
| 451 | pktout.body[10] = (len*8) & 0xFF; |
| 452 | memcpy(pktout.body+11, rsabuf, len); |
| 453 | pktout.body[len+11] = pktout.body[len+12] = 0; /* protocol flags */ |
| 454 | pktout.body[len+13] = pktout.body[len+14] = 0; |
| 455 | s_wrpkt(); |
| 456 | logevent("Trying to enable encryption..."); |
| 457 | |
| 458 | free(rsabuf); |
| 459 | |
| 460 | cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish : |
| 461 | cipher_type == SSH_CIPHER_DES ? &ssh_des : |
| 462 | &ssh_3des; |
| 463 | cipher->sesskey(session_key); |
| 464 | |
| 465 | do { crReturnV; } while (!ispkt); |
| 466 | |
| 467 | if (pktin.type != SSH_SMSG_SUCCESS) |
| 468 | fatalbox("Encryption not successfully enabled"); |
| 469 | |
| 470 | logevent("Successfully started encryption"); |
| 471 | |
| 472 | fflush(stdout); |
| 473 | { |
| 474 | static char username[100]; |
| 475 | static int pos = 0; |
| 476 | static char c; |
| 477 | if (!*cfg.username) { |
| 478 | c_write("login as: ", 10); |
| 479 | while (pos >= 0) { |
| 480 | do { crReturnV; } while (ispkt); |
| 481 | while (inlen--) switch (c = *in++) { |
| 482 | case 10: case 13: |
| 483 | username[pos] = 0; |
| 484 | pos = -1; |
| 485 | break; |
| 486 | case 8: case 127: |
| 487 | if (pos > 0) { |
| 488 | c_write("\b \b", 3); |
| 489 | pos--; |
| 490 | } |
| 491 | break; |
| 492 | case 21: case 27: |
| 493 | while (pos > 0) { |
| 494 | c_write("\b \b", 3); |
| 495 | pos--; |
| 496 | } |
| 497 | break; |
| 498 | case 3: case 4: |
| 499 | random_save_seed(); |
| 500 | exit(0); |
| 501 | break; |
| 502 | default: |
| 503 | if (((c >= ' ' && c <= '~') || |
| 504 | ((unsigned char)c >= 160)) && pos < 40) { |
| 505 | username[pos++] = c; |
| 506 | c_write(&c, 1); |
| 507 | } |
| 508 | break; |
| 509 | } |
| 510 | } |
| 511 | c_write("\r\n", 2); |
| 512 | username[strcspn(username, "\n\r")] = '\0'; |
| 513 | } else { |
| 514 | char stuff[200]; |
| 515 | strncpy(username, cfg.username, 99); |
| 516 | username[99] = '\0'; |
| 517 | sprintf(stuff, "Sent username \"%s\".\r\n", username); |
| 518 | c_write(stuff, strlen(stuff)); |
| 519 | } |
| 520 | s_wrpkt_start(SSH_CMSG_USER, 4+strlen(username)); |
| 521 | { |
| 522 | char userlog[20+sizeof(username)]; |
| 523 | sprintf(userlog, "Sent username \"%s\"", username); |
| 524 | logevent(userlog); |
| 525 | } |
| 526 | pktout.body[0] = pktout.body[1] = pktout.body[2] = 0; |
| 527 | pktout.body[3] = strlen(username); |
| 528 | memcpy(pktout.body+4, username, strlen(username)); |
| 529 | s_wrpkt(); |
| 530 | } |
| 531 | |
| 532 | do { crReturnV; } while (!ispkt); |
| 533 | |
| 534 | while (pktin.type == SSH_SMSG_FAILURE) { |
| 535 | static char password[100]; |
| 536 | static int pos; |
| 537 | static char c; |
| 538 | static int pwpkt_type; |
| 539 | |
| 540 | /* |
| 541 | * Show password prompt, having first obtained it via a TIS |
| 542 | * exchange if we're doing TIS authentication. |
| 543 | */ |
| 544 | pwpkt_type = SSH_CMSG_AUTH_PASSWORD; |
| 545 | if (pktin.type == SSH_SMSG_FAILURE && |
| 546 | cfg.try_tis_auth && |
| 547 | (supported_auths_mask & (1<<SSH_AUTH_TIS))) { |
| 548 | pwpkt_type = SSH_CMSG_AUTH_TIS_RESPONSE; |
| 549 | logevent("Requested TIS authentication"); |
| 550 | s_wrpkt_start(SSH_CMSG_AUTH_TIS, 0); |
| 551 | s_wrpkt(); |
| 552 | do { crReturnV; } while (!ispkt); |
| 553 | if (pktin.type != SSH_SMSG_AUTH_TIS_CHALLENGE) { |
| 554 | logevent("TIS authentication declined"); |
| 555 | c_write("TIS authentication refused.\r\n", 29); |
| 556 | } else { |
| 557 | int challengelen = ((pktin.body[0] << 24) | |
| 558 | (pktin.body[1] << 16) | |
| 559 | (pktin.body[2] << 8) | |
| 560 | (pktin.body[3])); |
| 561 | logevent("Received TIS challenge"); |
| 562 | c_write(pktin.body+4, challengelen); |
| 563 | } |
| 564 | } |
| 565 | if (pwpkt_type == SSH_CMSG_AUTH_PASSWORD) |
| 566 | c_write("password: ", 10); |
| 567 | |
| 568 | pos = 0; |
| 569 | while (pos >= 0) { |
| 570 | do { crReturnV; } while (ispkt); |
| 571 | while (inlen--) switch (c = *in++) { |
| 572 | case 10: case 13: |
| 573 | password[pos] = 0; |
| 574 | pos = -1; |
| 575 | break; |
| 576 | case 8: case 127: |
| 577 | if (pos > 0) |
| 578 | pos--; |
| 579 | break; |
| 580 | case 21: case 27: |
| 581 | pos = 0; |
| 582 | break; |
| 583 | case 3: case 4: |
| 584 | random_save_seed(); |
| 585 | exit(0); |
| 586 | break; |
| 587 | default: |
| 588 | if (((c >= ' ' && c <= '~') || |
| 589 | ((unsigned char)c >= 160)) && pos < 40) |
| 590 | password[pos++] = c; |
| 591 | break; |
| 592 | } |
| 593 | } |
| 594 | c_write("\r\n", 2); |
| 595 | s_wrpkt_start(pwpkt_type, 4+strlen(password)); |
| 596 | pktout.body[0] = pktout.body[1] = pktout.body[2] = 0; |
| 597 | pktout.body[3] = strlen(password); |
| 598 | memcpy(pktout.body+4, password, strlen(password)); |
| 599 | s_wrpkt(); |
| 600 | logevent("Sent password"); |
| 601 | memset(password, 0, strlen(password)); |
| 602 | do { crReturnV; } while (!ispkt); |
| 603 | if (pktin.type == 15) { |
| 604 | c_write("Access denied\r\n", 15); |
| 605 | logevent("Authentication refused"); |
| 606 | } else if (pktin.type != 14) { |
| 607 | fatalbox("Strange packet received, type %d", pktin.type); |
| 608 | } |
| 609 | } |
| 610 | |
| 611 | logevent("Authentication successful"); |
| 612 | |
| 613 | if (!cfg.nopty) { |
| 614 | i = strlen(cfg.termtype); |
| 615 | s_wrpkt_start(SSH_CMSG_REQUEST_PTY, i+5*4+1); |
| 616 | pktout.body[0] = (i >> 24) & 0xFF; |
| 617 | pktout.body[1] = (i >> 16) & 0xFF; |
| 618 | pktout.body[2] = (i >> 8) & 0xFF; |
| 619 | pktout.body[3] = i & 0xFF; |
| 620 | memcpy(pktout.body+4, cfg.termtype, i); |
| 621 | i += 4; |
| 622 | pktout.body[i++] = (rows >> 24) & 0xFF; |
| 623 | pktout.body[i++] = (rows >> 16) & 0xFF; |
| 624 | pktout.body[i++] = (rows >> 8) & 0xFF; |
| 625 | pktout.body[i++] = rows & 0xFF; |
| 626 | pktout.body[i++] = (cols >> 24) & 0xFF; |
| 627 | pktout.body[i++] = (cols >> 16) & 0xFF; |
| 628 | pktout.body[i++] = (cols >> 8) & 0xFF; |
| 629 | pktout.body[i++] = cols & 0xFF; |
| 630 | memset(pktout.body+i, 0, 9); /* 0 pixwidth, 0 pixheight, 0.b endofopt */ |
| 631 | s_wrpkt(); |
| 632 | ssh_state = SSH_STATE_INTERMED; |
| 633 | do { crReturnV; } while (!ispkt); |
| 634 | if (pktin.type != SSH_SMSG_SUCCESS && pktin.type != SSH_SMSG_FAILURE) { |
| 635 | fatalbox("Protocol confusion"); |
| 636 | } else if (pktin.type == SSH_SMSG_FAILURE) { |
| 637 | c_write("Server refused to allocate pty\r\n", 32); |
| 638 | } |
| 639 | logevent("Allocated pty"); |
| 640 | } |
| 641 | |
| 642 | s_wrpkt_start(SSH_CMSG_EXEC_SHELL, 0); |
| 643 | s_wrpkt(); |
| 644 | logevent("Started session"); |
| 645 | |
| 646 | ssh_state = SSH_STATE_SESSION; |
| 647 | if (size_needed) |
| 648 | ssh_size(); |
| 649 | |
| 650 | while (1) { |
| 651 | crReturnV; |
| 652 | if (ispkt) { |
| 653 | if (pktin.type == SSH_SMSG_STDOUT_DATA || |
| 654 | pktin.type == SSH_SMSG_STDERR_DATA) { |
| 655 | long len = 0; |
| 656 | for (i = 0; i < 4; i++) |
| 657 | len = (len << 8) + pktin.body[i]; |
| 658 | c_write(pktin.body+4, len); |
| 659 | } else if (pktin.type == SSH_MSG_DISCONNECT) { |
| 660 | ssh_state = SSH_STATE_CLOSED; |
| 661 | logevent("Received disconnect request"); |
| 662 | } else if (pktin.type == SSH_SMSG_SUCCESS) { |
| 663 | /* may be from EXEC_SHELL on some servers */ |
| 664 | } else if (pktin.type == SSH_SMSG_FAILURE) { |
| 665 | /* may be from EXEC_SHELL on some servers |
| 666 | * if no pty is available or in other odd cases. Ignore */ |
| 667 | } else if (pktin.type == SSH_SMSG_EXITSTATUS) { |
| 668 | s_wrpkt_start(SSH_CMSG_EXIT_CONFIRMATION, 0); |
| 669 | s_wrpkt(); |
| 670 | } else { |
| 671 | fatalbox("Strange packet received: type %d", pktin.type); |
| 672 | } |
| 673 | } else { |
| 674 | s_wrpkt_start(SSH_CMSG_STDIN_DATA, 4+inlen); |
| 675 | pktout.body[0] = (inlen >> 24) & 0xFF; |
| 676 | pktout.body[1] = (inlen >> 16) & 0xFF; |
| 677 | pktout.body[2] = (inlen >> 8) & 0xFF; |
| 678 | pktout.body[3] = inlen & 0xFF; |
| 679 | memcpy(pktout.body+4, in, inlen); |
| 680 | s_wrpkt(); |
| 681 | } |
| 682 | } |
| 683 | |
| 684 | crFinishV; |
| 685 | } |
| 686 | |
| 687 | /* |
| 688 | * Called to set up the connection. Will arrange for WM_NETEVENT |
| 689 | * messages to be passed to the specified window, whose window |
| 690 | * procedure should then call telnet_msg(). |
| 691 | * |
| 692 | * Returns an error message, or NULL on success. |
| 693 | * |
| 694 | * Also places the canonical host name into `realhost'. |
| 695 | */ |
| 696 | static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) { |
| 697 | SOCKADDR_IN addr; |
| 698 | struct hostent *h; |
| 699 | unsigned long a; |
| 700 | #ifdef FWHACK |
| 701 | char *FWhost; |
| 702 | int FWport; |
| 703 | #endif |
| 704 | |
| 705 | #ifdef MSCRYPTOAPI |
| 706 | if(crypto_startup() == 0) |
| 707 | return "Microsoft high encryption pack not installed!"; |
| 708 | #endif |
| 709 | |
| 710 | savedhost = malloc(1+strlen(host)); |
| 711 | if (!savedhost) |
| 712 | fatalbox("Out of memory"); |
| 713 | strcpy(savedhost, host); |
| 714 | |
| 715 | #ifdef FWHACK |
| 716 | FWhost = host; |
| 717 | FWport = port; |
| 718 | host = FWSTR; |
| 719 | port = 23; |
| 720 | #endif |
| 721 | |
| 722 | /* |
| 723 | * Try to find host. |
| 724 | */ |
| 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"; |
| 733 | } |
| 734 | memcpy (&a, h->h_addr, sizeof(a)); |
| 735 | *realhost = h->h_name; |
| 736 | } else |
| 737 | *realhost = host; |
| 738 | #ifdef FWHACK |
| 739 | *realhost = FWhost; |
| 740 | #endif |
| 741 | a = ntohl(a); |
| 742 | |
| 743 | if (port < 0) |
| 744 | port = 22; /* default ssh port */ |
| 745 | |
| 746 | /* |
| 747 | * Open socket. |
| 748 | */ |
| 749 | s = socket(AF_INET, SOCK_STREAM, 0); |
| 750 | if (s == INVALID_SOCKET) |
| 751 | switch (WSAGetLastError()) { |
| 752 | case WSAENETDOWN: return "Network is down"; |
| 753 | case WSAEAFNOSUPPORT: return "TCP/IP support not present"; |
| 754 | default: return "socket(): unknown error"; |
| 755 | } |
| 756 | |
| 757 | /* |
| 758 | * Bind to local address. |
| 759 | */ |
| 760 | addr.sin_family = AF_INET; |
| 761 | addr.sin_addr.s_addr = htonl(INADDR_ANY); |
| 762 | addr.sin_port = htons(0); |
| 763 | if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
| 764 | switch (WSAGetLastError()) { |
| 765 | case WSAENETDOWN: return "Network is down"; |
| 766 | default: return "bind(): unknown error"; |
| 767 | } |
| 768 | |
| 769 | /* |
| 770 | * Connect to remote address. |
| 771 | */ |
| 772 | addr.sin_addr.s_addr = htonl(a); |
| 773 | addr.sin_port = htons((short)port); |
| 774 | if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) |
| 775 | switch (WSAGetLastError()) { |
| 776 | case WSAENETDOWN: return "Network is down"; |
| 777 | case WSAECONNREFUSED: return "Connection refused"; |
| 778 | case WSAENETUNREACH: return "Network is unreachable"; |
| 779 | case WSAEHOSTUNREACH: return "No route to host"; |
| 780 | default: return "connect(): unknown error"; |
| 781 | } |
| 782 | |
| 783 | #ifdef FWHACK |
| 784 | send(s, "connect ", 8, 0); |
| 785 | send(s, FWhost, strlen(FWhost), 0); |
| 786 | { |
| 787 | char buf[20]; |
| 788 | sprintf(buf, " %d\n", FWport); |
| 789 | send (s, buf, strlen(buf), 0); |
| 790 | } |
| 791 | #endif |
| 792 | |
| 793 | if (!do_ssh_init()) |
| 794 | return "Protocol initialisation error"; |
| 795 | |
| 796 | if (WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR) |
| 797 | switch (WSAGetLastError()) { |
| 798 | case WSAENETDOWN: return "Network is down"; |
| 799 | default: return "WSAAsyncSelect(): unknown error"; |
| 800 | } |
| 801 | |
| 802 | return NULL; |
| 803 | } |
| 804 | |
| 805 | /* |
| 806 | * Process a WM_NETEVENT message. Will return 0 if the connection |
| 807 | * has closed, or <0 for a socket error. |
| 808 | */ |
| 809 | static int ssh_msg (WPARAM wParam, LPARAM lParam) { |
| 810 | int ret; |
| 811 | char buf[256]; |
| 812 | |
| 813 | /* |
| 814 | * Because reading less than the whole of the available pending |
| 815 | * data can generate an FD_READ event, we need to allow for the |
| 816 | * possibility that FD_READ may arrive with FD_CLOSE already in |
| 817 | * the queue; so it's possible that we can get here even with s |
| 818 | * invalid. If so, we return 1 and don't worry about it. |
| 819 | */ |
| 820 | if (s == INVALID_SOCKET) |
| 821 | return 1; |
| 822 | |
| 823 | if (WSAGETSELECTERROR(lParam) != 0) |
| 824 | return -WSAGETSELECTERROR(lParam); |
| 825 | |
| 826 | switch (WSAGETSELECTEVENT(lParam)) { |
| 827 | case FD_READ: |
| 828 | case FD_CLOSE: |
| 829 | ret = recv(s, buf, sizeof(buf), 0); |
| 830 | if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK) |
| 831 | return 1; |
| 832 | if (ret < 0) /* any _other_ error */ |
| 833 | return -10000-WSAGetLastError(); |
| 834 | if (ret == 0) { |
| 835 | s = INVALID_SOCKET; |
| 836 | return 0; |
| 837 | } |
| 838 | ssh_gotdata (buf, ret); |
| 839 | return 1; |
| 840 | } |
| 841 | return 1; /* shouldn't happen, but WTF */ |
| 842 | } |
| 843 | |
| 844 | /* |
| 845 | * Called to send data down the Telnet connection. |
| 846 | */ |
| 847 | static void ssh_send (char *buf, int len) { |
| 848 | if (s == INVALID_SOCKET) |
| 849 | return; |
| 850 | |
| 851 | ssh_protocol(buf, len, 0); |
| 852 | } |
| 853 | |
| 854 | /* |
| 855 | * Called to set the size of the window from Telnet's POV. |
| 856 | */ |
| 857 | static void ssh_size(void) { |
| 858 | switch (ssh_state) { |
| 859 | case SSH_STATE_BEFORE_SIZE: |
| 860 | case SSH_STATE_CLOSED: |
| 861 | break; /* do nothing */ |
| 862 | case SSH_STATE_INTERMED: |
| 863 | size_needed = TRUE; /* buffer for later */ |
| 864 | break; |
| 865 | case SSH_STATE_SESSION: |
| 866 | if (!cfg.nopty) { |
| 867 | s_wrpkt_start(11, 16); |
| 868 | pktout.body[0] = (rows >> 24) & 0xFF; |
| 869 | pktout.body[1] = (rows >> 16) & 0xFF; |
| 870 | pktout.body[2] = (rows >> 8) & 0xFF; |
| 871 | pktout.body[3] = rows & 0xFF; |
| 872 | pktout.body[4] = (cols >> 24) & 0xFF; |
| 873 | pktout.body[5] = (cols >> 16) & 0xFF; |
| 874 | pktout.body[6] = (cols >> 8) & 0xFF; |
| 875 | pktout.body[7] = cols & 0xFF; |
| 876 | memset(pktout.body+8, 0, 8); |
| 877 | s_wrpkt(); |
| 878 | } |
| 879 | } |
| 880 | } |
| 881 | |
| 882 | /* |
| 883 | * (Send Telnet special codes) |
| 884 | */ |
| 885 | static void ssh_special (Telnet_Special code) { |
| 886 | /* do nothing */ |
| 887 | } |
| 888 | |
| 889 | Backend ssh_backend = { |
| 890 | ssh_init, |
| 891 | ssh_msg, |
| 892 | ssh_send, |
| 893 | ssh_size, |
| 894 | ssh_special |
| 895 | }; |