1 /* 2 * Copyright 2002 Niels Provos <provos@citi.umich.edu> 3 * Copyright 2002 Markus Friedl <markus@openbsd.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include "includes.h" 28 RCSID("$OpenBSD: monitor_wrap.c,v 1.35 2003/11/17 11:06:07 markus Exp $"); 29 RCSID("$FreeBSD$"); 30 31 #include <openssl/bn.h> 32 #include <openssl/dh.h> 33 34 #include "ssh.h" 35 #include "dh.h" 36 #include "kex.h" 37 #include "auth.h" 38 #include "auth-options.h" 39 #include "buffer.h" 40 #include "bufaux.h" 41 #include "packet.h" 42 #include "mac.h" 43 #include "log.h" 44 #ifdef TARGET_OS_MAC /* XXX Broken krb5 headers on Mac */ 45 #undef TARGET_OS_MAC 46 #include "zlib.h" 47 #define TARGET_OS_MAC 1 48 #else 49 #include "zlib.h" 50 #endif 51 #include "monitor.h" 52 #include "monitor_wrap.h" 53 #include "xmalloc.h" 54 #include "atomicio.h" 55 #include "monitor_fdpass.h" 56 #include "getput.h" 57 #include "servconf.h" 58 59 #include "auth.h" 60 #include "channels.h" 61 #include "session.h" 62 63 #ifdef GSSAPI 64 #include "ssh-gss.h" 65 #endif 66 67 /* Imports */ 68 extern int compat20; 69 extern Newkeys *newkeys[]; 70 extern z_stream incoming_stream; 71 extern z_stream outgoing_stream; 72 extern struct monitor *pmonitor; 73 extern Buffer input, output; 74 extern ServerOptions options; 75 76 int 77 mm_is_monitor(void) 78 { 79 /* 80 * m_pid is only set in the privileged part, and 81 * points to the unprivileged child. 82 */ 83 return (pmonitor && pmonitor->m_pid > 0); 84 } 85 86 void 87 mm_request_send(int socket, enum monitor_reqtype type, Buffer *m) 88 { 89 u_int mlen = buffer_len(m); 90 u_char buf[5]; 91 92 debug3("%s entering: type %d", __func__, type); 93 94 PUT_32BIT(buf, mlen + 1); 95 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */ 96 if (atomicio(vwrite, socket, buf, sizeof(buf)) != sizeof(buf)) 97 fatal("%s: write", __func__); 98 if (atomicio(vwrite, socket, buffer_ptr(m), mlen) != mlen) 99 fatal("%s: write", __func__); 100 } 101 102 void 103 mm_request_receive(int socket, Buffer *m) 104 { 105 u_char buf[4]; 106 u_int msg_len; 107 ssize_t res; 108 109 debug3("%s entering", __func__); 110 111 res = atomicio(read, socket, buf, sizeof(buf)); 112 if (res != sizeof(buf)) { 113 if (res == 0) 114 cleanup_exit(255); 115 fatal("%s: read: %ld", __func__, (long)res); 116 } 117 msg_len = GET_32BIT(buf); 118 if (msg_len > 256 * 1024) 119 fatal("%s: read: bad msg_len %d", __func__, msg_len); 120 buffer_clear(m); 121 buffer_append_space(m, msg_len); 122 res = atomicio(read, socket, buffer_ptr(m), msg_len); 123 if (res != msg_len) 124 fatal("%s: read: %ld != msg_len", __func__, (long)res); 125 } 126 127 void 128 mm_request_receive_expect(int socket, enum monitor_reqtype type, Buffer *m) 129 { 130 u_char rtype; 131 132 debug3("%s entering: type %d", __func__, type); 133 134 mm_request_receive(socket, m); 135 rtype = buffer_get_char(m); 136 if (rtype != type) 137 fatal("%s: read: rtype %d != type %d", __func__, 138 rtype, type); 139 } 140 141 DH * 142 mm_choose_dh(int min, int nbits, int max) 143 { 144 BIGNUM *p, *g; 145 int success = 0; 146 Buffer m; 147 148 buffer_init(&m); 149 buffer_put_int(&m, min); 150 buffer_put_int(&m, nbits); 151 buffer_put_int(&m, max); 152 153 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m); 154 155 debug3("%s: waiting for MONITOR_ANS_MODULI", __func__); 156 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m); 157 158 success = buffer_get_char(&m); 159 if (success == 0) 160 fatal("%s: MONITOR_ANS_MODULI failed", __func__); 161 162 if ((p = BN_new()) == NULL) 163 fatal("%s: BN_new failed", __func__); 164 if ((g = BN_new()) == NULL) 165 fatal("%s: BN_new failed", __func__); 166 buffer_get_bignum2(&m, p); 167 buffer_get_bignum2(&m, g); 168 169 debug3("%s: remaining %d", __func__, buffer_len(&m)); 170 buffer_free(&m); 171 172 return (dh_new_group(g, p)); 173 } 174 175 int 176 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen) 177 { 178 Kex *kex = *pmonitor->m_pkex; 179 Buffer m; 180 181 debug3("%s entering", __func__); 182 183 buffer_init(&m); 184 buffer_put_int(&m, kex->host_key_index(key)); 185 buffer_put_string(&m, data, datalen); 186 187 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m); 188 189 debug3("%s: waiting for MONITOR_ANS_SIGN", __func__); 190 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m); 191 *sigp = buffer_get_string(&m, lenp); 192 buffer_free(&m); 193 194 return (0); 195 } 196 197 struct passwd * 198 mm_getpwnamallow(const char *login) 199 { 200 Buffer m; 201 struct passwd *pw; 202 u_int pwlen; 203 204 debug3("%s entering", __func__); 205 206 buffer_init(&m); 207 buffer_put_cstring(&m, login); 208 209 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m); 210 211 debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__); 212 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m); 213 214 if (buffer_get_char(&m) == 0) { 215 buffer_free(&m); 216 return (NULL); 217 } 218 pw = buffer_get_string(&m, &pwlen); 219 if (pwlen != sizeof(struct passwd)) 220 fatal("%s: struct passwd size mismatch", __func__); 221 pw->pw_name = buffer_get_string(&m, NULL); 222 pw->pw_passwd = buffer_get_string(&m, NULL); 223 pw->pw_gecos = buffer_get_string(&m, NULL); 224 #ifdef HAVE_PW_CLASS_IN_PASSWD 225 pw->pw_class = buffer_get_string(&m, NULL); 226 #endif 227 pw->pw_dir = buffer_get_string(&m, NULL); 228 pw->pw_shell = buffer_get_string(&m, NULL); 229 buffer_free(&m); 230 231 return (pw); 232 } 233 234 char * 235 mm_auth2_read_banner(void) 236 { 237 Buffer m; 238 char *banner; 239 240 debug3("%s entering", __func__); 241 242 buffer_init(&m); 243 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m); 244 buffer_clear(&m); 245 246 mm_request_receive_expect(pmonitor->m_recvfd, 247 MONITOR_ANS_AUTH2_READ_BANNER, &m); 248 banner = buffer_get_string(&m, NULL); 249 buffer_free(&m); 250 251 /* treat empty banner as missing banner */ 252 if (strlen(banner) == 0) { 253 xfree(banner); 254 banner = NULL; 255 } 256 return (banner); 257 } 258 259 /* Inform the privileged process about service and style */ 260 261 void 262 mm_inform_authserv(char *service, char *style) 263 { 264 Buffer m; 265 266 debug3("%s entering", __func__); 267 268 buffer_init(&m); 269 buffer_put_cstring(&m, service); 270 buffer_put_cstring(&m, style ? style : ""); 271 272 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m); 273 274 buffer_free(&m); 275 } 276 277 /* Do the password authentication */ 278 int 279 mm_auth_password(Authctxt *authctxt, char *password) 280 { 281 Buffer m; 282 int authenticated = 0; 283 284 debug3("%s entering", __func__); 285 286 buffer_init(&m); 287 buffer_put_cstring(&m, password); 288 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m); 289 290 debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__); 291 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m); 292 293 authenticated = buffer_get_int(&m); 294 295 buffer_free(&m); 296 297 debug3("%s: user %sauthenticated", 298 __func__, authenticated ? "" : "not "); 299 return (authenticated); 300 } 301 302 int 303 mm_user_key_allowed(struct passwd *pw, Key *key) 304 { 305 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key)); 306 } 307 308 int 309 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host, 310 Key *key) 311 { 312 return (mm_key_allowed(MM_HOSTKEY, user, host, key)); 313 } 314 315 int 316 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user, 317 char *host, Key *key) 318 { 319 int ret; 320 321 key->type = KEY_RSA; /* XXX hack for key_to_blob */ 322 ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key); 323 key->type = KEY_RSA1; 324 return (ret); 325 } 326 327 static void 328 mm_send_debug(Buffer *m) 329 { 330 char *msg; 331 332 while (buffer_len(m)) { 333 msg = buffer_get_string(m, NULL); 334 debug3("%s: Sending debug: %s", __func__, msg); 335 packet_send_debug("%s", msg); 336 xfree(msg); 337 } 338 } 339 340 int 341 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key) 342 { 343 Buffer m; 344 u_char *blob; 345 u_int len; 346 int allowed = 0, have_forced = 0; 347 348 debug3("%s entering", __func__); 349 350 /* Convert the key to a blob and the pass it over */ 351 if (!key_to_blob(key, &blob, &len)) 352 return (0); 353 354 buffer_init(&m); 355 buffer_put_int(&m, type); 356 buffer_put_cstring(&m, user ? user : ""); 357 buffer_put_cstring(&m, host ? host : ""); 358 buffer_put_string(&m, blob, len); 359 xfree(blob); 360 361 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m); 362 363 debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__); 364 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m); 365 366 allowed = buffer_get_int(&m); 367 368 /* fake forced command */ 369 auth_clear_options(); 370 have_forced = buffer_get_int(&m); 371 forced_command = have_forced ? xstrdup("true") : NULL; 372 373 /* Send potential debug messages */ 374 mm_send_debug(&m); 375 376 buffer_free(&m); 377 378 return (allowed); 379 } 380 381 /* 382 * This key verify needs to send the key type along, because the 383 * privileged parent makes the decision if the key is allowed 384 * for authentication. 385 */ 386 387 int 388 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen) 389 { 390 Buffer m; 391 u_char *blob; 392 u_int len; 393 int verified = 0; 394 395 debug3("%s entering", __func__); 396 397 /* Convert the key to a blob and the pass it over */ 398 if (!key_to_blob(key, &blob, &len)) 399 return (0); 400 401 buffer_init(&m); 402 buffer_put_string(&m, blob, len); 403 buffer_put_string(&m, sig, siglen); 404 buffer_put_string(&m, data, datalen); 405 xfree(blob); 406 407 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m); 408 409 debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__); 410 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m); 411 412 verified = buffer_get_int(&m); 413 414 buffer_free(&m); 415 416 return (verified); 417 } 418 419 /* Export key state after authentication */ 420 Newkeys * 421 mm_newkeys_from_blob(u_char *blob, int blen) 422 { 423 Buffer b; 424 u_int len; 425 Newkeys *newkey = NULL; 426 Enc *enc; 427 Mac *mac; 428 Comp *comp; 429 430 debug3("%s: %p(%d)", __func__, blob, blen); 431 #ifdef DEBUG_PK 432 dump_base64(stderr, blob, blen); 433 #endif 434 buffer_init(&b); 435 buffer_append(&b, blob, blen); 436 437 newkey = xmalloc(sizeof(*newkey)); 438 enc = &newkey->enc; 439 mac = &newkey->mac; 440 comp = &newkey->comp; 441 442 /* Enc structure */ 443 enc->name = buffer_get_string(&b, NULL); 444 buffer_get(&b, &enc->cipher, sizeof(enc->cipher)); 445 enc->enabled = buffer_get_int(&b); 446 enc->block_size = buffer_get_int(&b); 447 enc->key = buffer_get_string(&b, &enc->key_len); 448 enc->iv = buffer_get_string(&b, &len); 449 if (len != enc->block_size) 450 fatal("%s: bad ivlen: expected %u != %u", __func__, 451 enc->block_size, len); 452 453 if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher) 454 fatal("%s: bad cipher name %s or pointer %p", __func__, 455 enc->name, enc->cipher); 456 457 /* Mac structure */ 458 mac->name = buffer_get_string(&b, NULL); 459 if (mac->name == NULL || mac_init(mac, mac->name) == -1) 460 fatal("%s: can not init mac %s", __func__, mac->name); 461 mac->enabled = buffer_get_int(&b); 462 mac->key = buffer_get_string(&b, &len); 463 if (len > mac->key_len) 464 fatal("%s: bad mac key length: %u > %d", __func__, len, 465 mac->key_len); 466 mac->key_len = len; 467 468 /* Comp structure */ 469 comp->type = buffer_get_int(&b); 470 comp->enabled = buffer_get_int(&b); 471 comp->name = buffer_get_string(&b, NULL); 472 473 len = buffer_len(&b); 474 if (len != 0) 475 error("newkeys_from_blob: remaining bytes in blob %u", len); 476 buffer_free(&b); 477 return (newkey); 478 } 479 480 int 481 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp) 482 { 483 Buffer b; 484 int len; 485 Enc *enc; 486 Mac *mac; 487 Comp *comp; 488 Newkeys *newkey = newkeys[mode]; 489 490 debug3("%s: converting %p", __func__, newkey); 491 492 if (newkey == NULL) { 493 error("%s: newkey == NULL", __func__); 494 return 0; 495 } 496 enc = &newkey->enc; 497 mac = &newkey->mac; 498 comp = &newkey->comp; 499 500 buffer_init(&b); 501 /* Enc structure */ 502 buffer_put_cstring(&b, enc->name); 503 /* The cipher struct is constant and shared, you export pointer */ 504 buffer_append(&b, &enc->cipher, sizeof(enc->cipher)); 505 buffer_put_int(&b, enc->enabled); 506 buffer_put_int(&b, enc->block_size); 507 buffer_put_string(&b, enc->key, enc->key_len); 508 packet_get_keyiv(mode, enc->iv, enc->block_size); 509 buffer_put_string(&b, enc->iv, enc->block_size); 510 511 /* Mac structure */ 512 buffer_put_cstring(&b, mac->name); 513 buffer_put_int(&b, mac->enabled); 514 buffer_put_string(&b, mac->key, mac->key_len); 515 516 /* Comp structure */ 517 buffer_put_int(&b, comp->type); 518 buffer_put_int(&b, comp->enabled); 519 buffer_put_cstring(&b, comp->name); 520 521 len = buffer_len(&b); 522 if (lenp != NULL) 523 *lenp = len; 524 if (blobp != NULL) { 525 *blobp = xmalloc(len); 526 memcpy(*blobp, buffer_ptr(&b), len); 527 } 528 memset(buffer_ptr(&b), 0, len); 529 buffer_free(&b); 530 return len; 531 } 532 533 static void 534 mm_send_kex(Buffer *m, Kex *kex) 535 { 536 buffer_put_string(m, kex->session_id, kex->session_id_len); 537 buffer_put_int(m, kex->we_need); 538 buffer_put_int(m, kex->hostkey_type); 539 buffer_put_int(m, kex->kex_type); 540 buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my)); 541 buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer)); 542 buffer_put_int(m, kex->flags); 543 buffer_put_cstring(m, kex->client_version_string); 544 buffer_put_cstring(m, kex->server_version_string); 545 } 546 547 void 548 mm_send_keystate(struct monitor *pmonitor) 549 { 550 Buffer m; 551 u_char *blob, *p; 552 u_int bloblen, plen; 553 u_int32_t seqnr, packets; 554 u_int64_t blocks; 555 556 buffer_init(&m); 557 558 if (!compat20) { 559 u_char iv[24]; 560 u_char *key; 561 u_int ivlen, keylen; 562 563 buffer_put_int(&m, packet_get_protocol_flags()); 564 565 buffer_put_int(&m, packet_get_ssh1_cipher()); 566 567 debug3("%s: Sending ssh1 KEY+IV", __func__); 568 keylen = packet_get_encryption_key(NULL); 569 key = xmalloc(keylen+1); /* add 1 if keylen == 0 */ 570 keylen = packet_get_encryption_key(key); 571 buffer_put_string(&m, key, keylen); 572 memset(key, 0, keylen); 573 xfree(key); 574 575 ivlen = packet_get_keyiv_len(MODE_OUT); 576 packet_get_keyiv(MODE_OUT, iv, ivlen); 577 buffer_put_string(&m, iv, ivlen); 578 ivlen = packet_get_keyiv_len(MODE_OUT); 579 packet_get_keyiv(MODE_IN, iv, ivlen); 580 buffer_put_string(&m, iv, ivlen); 581 goto skip; 582 } else { 583 /* Kex for rekeying */ 584 mm_send_kex(&m, *pmonitor->m_pkex); 585 } 586 587 debug3("%s: Sending new keys: %p %p", 588 __func__, newkeys[MODE_OUT], newkeys[MODE_IN]); 589 590 /* Keys from Kex */ 591 if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen)) 592 fatal("%s: conversion of newkeys failed", __func__); 593 594 buffer_put_string(&m, blob, bloblen); 595 xfree(blob); 596 597 if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen)) 598 fatal("%s: conversion of newkeys failed", __func__); 599 600 buffer_put_string(&m, blob, bloblen); 601 xfree(blob); 602 603 packet_get_state(MODE_OUT, &seqnr, &blocks, &packets); 604 buffer_put_int(&m, seqnr); 605 buffer_put_int64(&m, blocks); 606 buffer_put_int(&m, packets); 607 packet_get_state(MODE_IN, &seqnr, &blocks, &packets); 608 buffer_put_int(&m, seqnr); 609 buffer_put_int64(&m, blocks); 610 buffer_put_int(&m, packets); 611 612 debug3("%s: New keys have been sent", __func__); 613 skip: 614 /* More key context */ 615 plen = packet_get_keycontext(MODE_OUT, NULL); 616 p = xmalloc(plen+1); 617 packet_get_keycontext(MODE_OUT, p); 618 buffer_put_string(&m, p, plen); 619 xfree(p); 620 621 plen = packet_get_keycontext(MODE_IN, NULL); 622 p = xmalloc(plen+1); 623 packet_get_keycontext(MODE_IN, p); 624 buffer_put_string(&m, p, plen); 625 xfree(p); 626 627 /* Compression state */ 628 debug3("%s: Sending compression state", __func__); 629 buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream)); 630 buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream)); 631 632 /* Network I/O buffers */ 633 buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input)); 634 buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output)); 635 636 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m); 637 debug3("%s: Finished sending state", __func__); 638 639 buffer_free(&m); 640 } 641 642 int 643 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen) 644 { 645 Buffer m; 646 char *p; 647 int success = 0; 648 649 buffer_init(&m); 650 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m); 651 652 debug3("%s: waiting for MONITOR_ANS_PTY", __func__); 653 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m); 654 655 success = buffer_get_int(&m); 656 if (success == 0) { 657 debug3("%s: pty alloc failed", __func__); 658 buffer_free(&m); 659 return (0); 660 } 661 p = buffer_get_string(&m, NULL); 662 buffer_free(&m); 663 664 strlcpy(namebuf, p, namebuflen); /* Possible truncation */ 665 xfree(p); 666 667 *ptyfd = mm_receive_fd(pmonitor->m_recvfd); 668 *ttyfd = mm_receive_fd(pmonitor->m_recvfd); 669 670 /* Success */ 671 return (1); 672 } 673 674 void 675 mm_session_pty_cleanup2(Session *s) 676 { 677 Buffer m; 678 679 if (s->ttyfd == -1) 680 return; 681 buffer_init(&m); 682 buffer_put_cstring(&m, s->tty); 683 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m); 684 buffer_free(&m); 685 686 /* closed dup'ed master */ 687 if (close(s->ptymaster) < 0) 688 error("close(s->ptymaster): %s", strerror(errno)); 689 690 /* unlink pty from session */ 691 s->ttyfd = -1; 692 } 693 694 #ifdef USE_PAM 695 void 696 mm_start_pam(Authctxt *authctxt) 697 { 698 Buffer m; 699 700 debug3("%s entering", __func__); 701 if (!options.use_pam) 702 fatal("UsePAM=no, but ended up in %s anyway", __func__); 703 704 buffer_init(&m); 705 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m); 706 707 buffer_free(&m); 708 } 709 710 u_int 711 mm_do_pam_account(void) 712 { 713 Buffer m; 714 u_int ret; 715 716 debug3("%s entering", __func__); 717 if (!options.use_pam) 718 fatal("UsePAM=no, but ended up in %s anyway", __func__); 719 720 buffer_init(&m); 721 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m); 722 723 mm_request_receive_expect(pmonitor->m_recvfd, 724 MONITOR_ANS_PAM_ACCOUNT, &m); 725 ret = buffer_get_int(&m); 726 727 buffer_free(&m); 728 729 debug3("%s returning %d", __func__, ret); 730 731 return (ret); 732 } 733 734 void * 735 mm_sshpam_init_ctx(Authctxt *authctxt) 736 { 737 Buffer m; 738 int success; 739 740 debug3("%s", __func__); 741 buffer_init(&m); 742 buffer_put_cstring(&m, authctxt->user); 743 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m); 744 debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__); 745 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m); 746 success = buffer_get_int(&m); 747 if (success == 0) { 748 debug3("%s: pam_init_ctx failed", __func__); 749 buffer_free(&m); 750 return (NULL); 751 } 752 buffer_free(&m); 753 return (authctxt); 754 } 755 756 int 757 mm_sshpam_query(void *ctx, char **name, char **info, 758 u_int *num, char ***prompts, u_int **echo_on) 759 { 760 Buffer m; 761 int i, ret; 762 763 debug3("%s", __func__); 764 buffer_init(&m); 765 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m); 766 debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__); 767 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m); 768 ret = buffer_get_int(&m); 769 debug3("%s: pam_query returned %d", __func__, ret); 770 *name = buffer_get_string(&m, NULL); 771 *info = buffer_get_string(&m, NULL); 772 *num = buffer_get_int(&m); 773 *prompts = xmalloc((*num + 1) * sizeof(char *)); 774 *echo_on = xmalloc((*num + 1) * sizeof(u_int)); 775 for (i = 0; i < *num; ++i) { 776 (*prompts)[i] = buffer_get_string(&m, NULL); 777 (*echo_on)[i] = buffer_get_int(&m); 778 } 779 buffer_free(&m); 780 return (ret); 781 } 782 783 int 784 mm_sshpam_respond(void *ctx, u_int num, char **resp) 785 { 786 Buffer m; 787 int i, ret; 788 789 debug3("%s", __func__); 790 buffer_init(&m); 791 buffer_put_int(&m, num); 792 for (i = 0; i < num; ++i) 793 buffer_put_cstring(&m, resp[i]); 794 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m); 795 debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__); 796 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m); 797 ret = buffer_get_int(&m); 798 debug3("%s: pam_respond returned %d", __func__, ret); 799 buffer_free(&m); 800 return (ret); 801 } 802 803 void 804 mm_sshpam_free_ctx(void *ctxtp) 805 { 806 Buffer m; 807 808 debug3("%s", __func__); 809 buffer_init(&m); 810 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m); 811 debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__); 812 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m); 813 buffer_free(&m); 814 } 815 #endif /* USE_PAM */ 816 817 /* Request process termination */ 818 819 void 820 mm_terminate(void) 821 { 822 Buffer m; 823 824 buffer_init(&m); 825 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m); 826 buffer_free(&m); 827 } 828 829 int 830 mm_ssh1_session_key(BIGNUM *num) 831 { 832 int rsafail; 833 Buffer m; 834 835 buffer_init(&m); 836 buffer_put_bignum2(&m, num); 837 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m); 838 839 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m); 840 841 rsafail = buffer_get_int(&m); 842 buffer_get_bignum2(&m, num); 843 844 buffer_free(&m); 845 846 return (rsafail); 847 } 848 849 static void 850 mm_chall_setup(char **name, char **infotxt, u_int *numprompts, 851 char ***prompts, u_int **echo_on) 852 { 853 *name = xstrdup(""); 854 *infotxt = xstrdup(""); 855 *numprompts = 1; 856 *prompts = xmalloc(*numprompts * sizeof(char *)); 857 *echo_on = xmalloc(*numprompts * sizeof(u_int)); 858 (*echo_on)[0] = 0; 859 } 860 861 int 862 mm_bsdauth_query(void *ctx, char **name, char **infotxt, 863 u_int *numprompts, char ***prompts, u_int **echo_on) 864 { 865 Buffer m; 866 u_int success; 867 char *challenge; 868 869 debug3("%s: entering", __func__); 870 871 buffer_init(&m); 872 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m); 873 874 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY, 875 &m); 876 success = buffer_get_int(&m); 877 if (success == 0) { 878 debug3("%s: no challenge", __func__); 879 buffer_free(&m); 880 return (-1); 881 } 882 883 /* Get the challenge, and format the response */ 884 challenge = buffer_get_string(&m, NULL); 885 buffer_free(&m); 886 887 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 888 (*prompts)[0] = challenge; 889 890 debug3("%s: received challenge: %s", __func__, challenge); 891 892 return (0); 893 } 894 895 int 896 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses) 897 { 898 Buffer m; 899 int authok; 900 901 debug3("%s: entering", __func__); 902 if (numresponses != 1) 903 return (-1); 904 905 buffer_init(&m); 906 buffer_put_cstring(&m, responses[0]); 907 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m); 908 909 mm_request_receive_expect(pmonitor->m_recvfd, 910 MONITOR_ANS_BSDAUTHRESPOND, &m); 911 912 authok = buffer_get_int(&m); 913 buffer_free(&m); 914 915 return ((authok == 0) ? -1 : 0); 916 } 917 918 #ifdef SKEY 919 int 920 mm_skey_query(void *ctx, char **name, char **infotxt, 921 u_int *numprompts, char ***prompts, u_int **echo_on) 922 { 923 Buffer m; 924 int len; 925 u_int success; 926 char *p, *challenge; 927 928 debug3("%s: entering", __func__); 929 930 buffer_init(&m); 931 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m); 932 933 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY, 934 &m); 935 success = buffer_get_int(&m); 936 if (success == 0) { 937 debug3("%s: no challenge", __func__); 938 buffer_free(&m); 939 return (-1); 940 } 941 942 /* Get the challenge, and format the response */ 943 challenge = buffer_get_string(&m, NULL); 944 buffer_free(&m); 945 946 debug3("%s: received challenge: %s", __func__, challenge); 947 948 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 949 950 len = strlen(challenge) + strlen(SKEY_PROMPT) + 1; 951 p = xmalloc(len); 952 strlcpy(p, challenge, len); 953 strlcat(p, SKEY_PROMPT, len); 954 (*prompts)[0] = p; 955 xfree(challenge); 956 957 return (0); 958 } 959 960 int 961 mm_skey_respond(void *ctx, u_int numresponses, char **responses) 962 { 963 Buffer m; 964 int authok; 965 966 debug3("%s: entering", __func__); 967 if (numresponses != 1) 968 return (-1); 969 970 buffer_init(&m); 971 buffer_put_cstring(&m, responses[0]); 972 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m); 973 974 mm_request_receive_expect(pmonitor->m_recvfd, 975 MONITOR_ANS_SKEYRESPOND, &m); 976 977 authok = buffer_get_int(&m); 978 buffer_free(&m); 979 980 return ((authok == 0) ? -1 : 0); 981 } 982 #endif 983 984 void 985 mm_ssh1_session_id(u_char session_id[16]) 986 { 987 Buffer m; 988 int i; 989 990 debug3("%s entering", __func__); 991 992 buffer_init(&m); 993 for (i = 0; i < 16; i++) 994 buffer_put_char(&m, session_id[i]); 995 996 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m); 997 buffer_free(&m); 998 } 999 1000 int 1001 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey) 1002 { 1003 Buffer m; 1004 Key *key; 1005 u_char *blob; 1006 u_int blen; 1007 int allowed = 0, have_forced = 0; 1008 1009 debug3("%s entering", __func__); 1010 1011 buffer_init(&m); 1012 buffer_put_bignum2(&m, client_n); 1013 1014 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m); 1015 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m); 1016 1017 allowed = buffer_get_int(&m); 1018 1019 /* fake forced command */ 1020 auth_clear_options(); 1021 have_forced = buffer_get_int(&m); 1022 forced_command = have_forced ? xstrdup("true") : NULL; 1023 1024 if (allowed && rkey != NULL) { 1025 blob = buffer_get_string(&m, &blen); 1026 if ((key = key_from_blob(blob, blen)) == NULL) 1027 fatal("%s: key_from_blob failed", __func__); 1028 *rkey = key; 1029 xfree(blob); 1030 } 1031 mm_send_debug(&m); 1032 buffer_free(&m); 1033 1034 return (allowed); 1035 } 1036 1037 BIGNUM * 1038 mm_auth_rsa_generate_challenge(Key *key) 1039 { 1040 Buffer m; 1041 BIGNUM *challenge; 1042 u_char *blob; 1043 u_int blen; 1044 1045 debug3("%s entering", __func__); 1046 1047 if ((challenge = BN_new()) == NULL) 1048 fatal("%s: BN_new failed", __func__); 1049 1050 key->type = KEY_RSA; /* XXX cheat for key_to_blob */ 1051 if (key_to_blob(key, &blob, &blen) == 0) 1052 fatal("%s: key_to_blob failed", __func__); 1053 key->type = KEY_RSA1; 1054 1055 buffer_init(&m); 1056 buffer_put_string(&m, blob, blen); 1057 xfree(blob); 1058 1059 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m); 1060 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m); 1061 1062 buffer_get_bignum2(&m, challenge); 1063 buffer_free(&m); 1064 1065 return (challenge); 1066 } 1067 1068 int 1069 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16]) 1070 { 1071 Buffer m; 1072 u_char *blob; 1073 u_int blen; 1074 int success = 0; 1075 1076 debug3("%s entering", __func__); 1077 1078 key->type = KEY_RSA; /* XXX cheat for key_to_blob */ 1079 if (key_to_blob(key, &blob, &blen) == 0) 1080 fatal("%s: key_to_blob failed", __func__); 1081 key->type = KEY_RSA1; 1082 1083 buffer_init(&m); 1084 buffer_put_string(&m, blob, blen); 1085 buffer_put_string(&m, response, 16); 1086 xfree(blob); 1087 1088 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m); 1089 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m); 1090 1091 success = buffer_get_int(&m); 1092 buffer_free(&m); 1093 1094 return (success); 1095 } 1096 1097 #ifdef GSSAPI 1098 OM_uint32 1099 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid) 1100 { 1101 Buffer m; 1102 OM_uint32 major; 1103 1104 /* Client doesn't get to see the context */ 1105 *ctx = NULL; 1106 1107 buffer_init(&m); 1108 buffer_put_string(&m, oid->elements, oid->length); 1109 1110 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m); 1111 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m); 1112 1113 major = buffer_get_int(&m); 1114 1115 buffer_free(&m); 1116 return (major); 1117 } 1118 1119 OM_uint32 1120 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in, 1121 gss_buffer_desc *out, OM_uint32 *flags) 1122 { 1123 Buffer m; 1124 OM_uint32 major; 1125 u_int len; 1126 1127 buffer_init(&m); 1128 buffer_put_string(&m, in->value, in->length); 1129 1130 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m); 1131 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m); 1132 1133 major = buffer_get_int(&m); 1134 out->value = buffer_get_string(&m, &len); 1135 out->length = len; 1136 if (flags) 1137 *flags = buffer_get_int(&m); 1138 1139 buffer_free(&m); 1140 1141 return (major); 1142 } 1143 1144 OM_uint32 1145 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic) 1146 { 1147 Buffer m; 1148 OM_uint32 major; 1149 1150 buffer_init(&m); 1151 buffer_put_string(&m, gssbuf->value, gssbuf->length); 1152 buffer_put_string(&m, gssmic->value, gssmic->length); 1153 1154 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m); 1155 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC, 1156 &m); 1157 1158 major = buffer_get_int(&m); 1159 buffer_free(&m); 1160 return(major); 1161 } 1162 1163 int 1164 mm_ssh_gssapi_userok(char *user) 1165 { 1166 Buffer m; 1167 int authenticated = 0; 1168 1169 buffer_init(&m); 1170 1171 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m); 1172 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK, 1173 &m); 1174 1175 authenticated = buffer_get_int(&m); 1176 1177 buffer_free(&m); 1178 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not "); 1179 return (authenticated); 1180 } 1181 #endif /* GSSAPI */ 1182