1 /* $OpenBSD: monitor_wrap.c,v 1.54 2006/08/12 20:46:46 miod Exp $ */ 2 /* 3 * Copyright 2002 Niels Provos <provos@citi.umich.edu> 4 * Copyright 2002 Markus Friedl <markus@openbsd.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include "includes.h" 29 __RCSID("$FreeBSD$"); 30 31 #include <sys/types.h> 32 #include <sys/uio.h> 33 34 #include <errno.h> 35 #include <pwd.h> 36 #include <signal.h> 37 #include <stdarg.h> 38 #include <stdio.h> 39 #include <string.h> 40 #include <unistd.h> 41 42 #include <openssl/bn.h> 43 #include <openssl/dh.h> 44 45 #include "xmalloc.h" 46 #include "ssh.h" 47 #include "dh.h" 48 #include "buffer.h" 49 #include "key.h" 50 #include "cipher.h" 51 #include "kex.h" 52 #include "hostfile.h" 53 #include "auth.h" 54 #include "auth-options.h" 55 #include "packet.h" 56 #include "mac.h" 57 #include "log.h" 58 #ifdef TARGET_OS_MAC /* XXX Broken krb5 headers on Mac */ 59 #undef TARGET_OS_MAC 60 #include "zlib.h" 61 #define TARGET_OS_MAC 1 62 #else 63 #include "zlib.h" 64 #endif 65 #include "monitor.h" 66 #ifdef GSSAPI 67 #include "ssh-gss.h" 68 #endif 69 #include "monitor_wrap.h" 70 #include "atomicio.h" 71 #include "monitor_fdpass.h" 72 #include "misc.h" 73 #include "servconf.h" 74 75 #include "channels.h" 76 #include "session.h" 77 78 /* Imports */ 79 extern int compat20; 80 extern Newkeys *newkeys[]; 81 extern z_stream incoming_stream; 82 extern z_stream outgoing_stream; 83 extern struct monitor *pmonitor; 84 extern Buffer input, output; 85 extern Buffer loginmsg; 86 extern ServerOptions options; 87 88 int 89 mm_is_monitor(void) 90 { 91 /* 92 * m_pid is only set in the privileged part, and 93 * points to the unprivileged child. 94 */ 95 return (pmonitor && pmonitor->m_pid > 0); 96 } 97 98 void 99 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m) 100 { 101 u_int mlen = buffer_len(m); 102 u_char buf[5]; 103 104 debug3("%s entering: type %d", __func__, type); 105 106 put_u32(buf, mlen + 1); 107 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */ 108 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf)) 109 fatal("%s: write: %s", __func__, strerror(errno)); 110 if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen) 111 fatal("%s: write: %s", __func__, strerror(errno)); 112 } 113 114 void 115 mm_request_receive(int sock, Buffer *m) 116 { 117 u_char buf[4]; 118 u_int msg_len; 119 120 debug3("%s entering", __func__); 121 122 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) { 123 if (errno == EPIPE) 124 cleanup_exit(255); 125 fatal("%s: read: %s", __func__, strerror(errno)); 126 } 127 msg_len = get_u32(buf); 128 if (msg_len > 256 * 1024) 129 fatal("%s: read: bad msg_len %d", __func__, msg_len); 130 buffer_clear(m); 131 buffer_append_space(m, msg_len); 132 if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len) 133 fatal("%s: read: %s", __func__, strerror(errno)); 134 } 135 136 void 137 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m) 138 { 139 u_char rtype; 140 141 debug3("%s entering: type %d", __func__, type); 142 143 mm_request_receive(sock, m); 144 rtype = buffer_get_char(m); 145 if (rtype != type) 146 fatal("%s: read: rtype %d != type %d", __func__, 147 rtype, type); 148 } 149 150 DH * 151 mm_choose_dh(int min, int nbits, int max) 152 { 153 BIGNUM *p, *g; 154 int success = 0; 155 Buffer m; 156 157 buffer_init(&m); 158 buffer_put_int(&m, min); 159 buffer_put_int(&m, nbits); 160 buffer_put_int(&m, max); 161 162 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m); 163 164 debug3("%s: waiting for MONITOR_ANS_MODULI", __func__); 165 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m); 166 167 success = buffer_get_char(&m); 168 if (success == 0) 169 fatal("%s: MONITOR_ANS_MODULI failed", __func__); 170 171 if ((p = BN_new()) == NULL) 172 fatal("%s: BN_new failed", __func__); 173 if ((g = BN_new()) == NULL) 174 fatal("%s: BN_new failed", __func__); 175 buffer_get_bignum2(&m, p); 176 buffer_get_bignum2(&m, g); 177 178 debug3("%s: remaining %d", __func__, buffer_len(&m)); 179 buffer_free(&m); 180 181 return (dh_new_group(g, p)); 182 } 183 184 int 185 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen) 186 { 187 Kex *kex = *pmonitor->m_pkex; 188 Buffer m; 189 190 debug3("%s entering", __func__); 191 192 buffer_init(&m); 193 buffer_put_int(&m, kex->host_key_index(key)); 194 buffer_put_string(&m, data, datalen); 195 196 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m); 197 198 debug3("%s: waiting for MONITOR_ANS_SIGN", __func__); 199 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m); 200 *sigp = buffer_get_string(&m, lenp); 201 buffer_free(&m); 202 203 return (0); 204 } 205 206 struct passwd * 207 mm_getpwnamallow(const char *username) 208 { 209 Buffer m; 210 struct passwd *pw; 211 u_int pwlen; 212 213 debug3("%s entering", __func__); 214 215 buffer_init(&m); 216 buffer_put_cstring(&m, username); 217 218 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m); 219 220 debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__); 221 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m); 222 223 if (buffer_get_char(&m) == 0) { 224 buffer_free(&m); 225 return (NULL); 226 } 227 pw = buffer_get_string(&m, &pwlen); 228 if (pwlen != sizeof(struct passwd)) 229 fatal("%s: struct passwd size mismatch", __func__); 230 pw->pw_name = buffer_get_string(&m, NULL); 231 pw->pw_passwd = buffer_get_string(&m, NULL); 232 pw->pw_gecos = buffer_get_string(&m, NULL); 233 #ifdef HAVE_PW_CLASS_IN_PASSWD 234 pw->pw_class = buffer_get_string(&m, NULL); 235 #endif 236 pw->pw_dir = buffer_get_string(&m, NULL); 237 pw->pw_shell = buffer_get_string(&m, NULL); 238 buffer_free(&m); 239 240 return (pw); 241 } 242 243 char * 244 mm_auth2_read_banner(void) 245 { 246 Buffer m; 247 char *banner; 248 249 debug3("%s entering", __func__); 250 251 buffer_init(&m); 252 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m); 253 buffer_clear(&m); 254 255 mm_request_receive_expect(pmonitor->m_recvfd, 256 MONITOR_ANS_AUTH2_READ_BANNER, &m); 257 banner = buffer_get_string(&m, NULL); 258 buffer_free(&m); 259 260 /* treat empty banner as missing banner */ 261 if (strlen(banner) == 0) { 262 xfree(banner); 263 banner = NULL; 264 } 265 return (banner); 266 } 267 268 /* Inform the privileged process about service and style */ 269 270 void 271 mm_inform_authserv(char *service, char *style) 272 { 273 Buffer m; 274 275 debug3("%s entering", __func__); 276 277 buffer_init(&m); 278 buffer_put_cstring(&m, service); 279 buffer_put_cstring(&m, style ? style : ""); 280 281 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m); 282 283 buffer_free(&m); 284 } 285 286 /* Do the password authentication */ 287 int 288 mm_auth_password(Authctxt *authctxt, char *password) 289 { 290 Buffer m; 291 int authenticated = 0; 292 293 debug3("%s entering", __func__); 294 295 buffer_init(&m); 296 buffer_put_cstring(&m, password); 297 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m); 298 299 debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__); 300 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m); 301 302 authenticated = buffer_get_int(&m); 303 304 buffer_free(&m); 305 306 debug3("%s: user %sauthenticated", 307 __func__, authenticated ? "" : "not "); 308 return (authenticated); 309 } 310 311 int 312 mm_user_key_allowed(struct passwd *pw, Key *key) 313 { 314 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key)); 315 } 316 317 int 318 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host, 319 Key *key) 320 { 321 return (mm_key_allowed(MM_HOSTKEY, user, host, key)); 322 } 323 324 int 325 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user, 326 char *host, Key *key) 327 { 328 int ret; 329 330 key->type = KEY_RSA; /* XXX hack for key_to_blob */ 331 ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key); 332 key->type = KEY_RSA1; 333 return (ret); 334 } 335 336 static void 337 mm_send_debug(Buffer *m) 338 { 339 char *msg; 340 341 while (buffer_len(m)) { 342 msg = buffer_get_string(m, NULL); 343 debug3("%s: Sending debug: %s", __func__, msg); 344 packet_send_debug("%s", msg); 345 xfree(msg); 346 } 347 } 348 349 int 350 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key) 351 { 352 Buffer m; 353 u_char *blob; 354 u_int len; 355 int allowed = 0, have_forced = 0; 356 357 debug3("%s entering", __func__); 358 359 /* Convert the key to a blob and the pass it over */ 360 if (!key_to_blob(key, &blob, &len)) 361 return (0); 362 363 buffer_init(&m); 364 buffer_put_int(&m, type); 365 buffer_put_cstring(&m, user ? user : ""); 366 buffer_put_cstring(&m, host ? host : ""); 367 buffer_put_string(&m, blob, len); 368 xfree(blob); 369 370 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m); 371 372 debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__); 373 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m); 374 375 allowed = buffer_get_int(&m); 376 377 /* fake forced command */ 378 auth_clear_options(); 379 have_forced = buffer_get_int(&m); 380 forced_command = have_forced ? xstrdup("true") : NULL; 381 382 /* Send potential debug messages */ 383 mm_send_debug(&m); 384 385 buffer_free(&m); 386 387 return (allowed); 388 } 389 390 /* 391 * This key verify needs to send the key type along, because the 392 * privileged parent makes the decision if the key is allowed 393 * for authentication. 394 */ 395 396 int 397 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen) 398 { 399 Buffer m; 400 u_char *blob; 401 u_int len; 402 int verified = 0; 403 404 debug3("%s entering", __func__); 405 406 /* Convert the key to a blob and the pass it over */ 407 if (!key_to_blob(key, &blob, &len)) 408 return (0); 409 410 buffer_init(&m); 411 buffer_put_string(&m, blob, len); 412 buffer_put_string(&m, sig, siglen); 413 buffer_put_string(&m, data, datalen); 414 xfree(blob); 415 416 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m); 417 418 debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__); 419 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m); 420 421 verified = buffer_get_int(&m); 422 423 buffer_free(&m); 424 425 return (verified); 426 } 427 428 /* Export key state after authentication */ 429 Newkeys * 430 mm_newkeys_from_blob(u_char *blob, int blen) 431 { 432 Buffer b; 433 u_int len; 434 Newkeys *newkey = NULL; 435 Enc *enc; 436 Mac *mac; 437 Comp *comp; 438 439 debug3("%s: %p(%d)", __func__, blob, blen); 440 #ifdef DEBUG_PK 441 dump_base64(stderr, blob, blen); 442 #endif 443 buffer_init(&b); 444 buffer_append(&b, blob, blen); 445 446 newkey = xmalloc(sizeof(*newkey)); 447 enc = &newkey->enc; 448 mac = &newkey->mac; 449 comp = &newkey->comp; 450 451 /* Enc structure */ 452 enc->name = buffer_get_string(&b, NULL); 453 buffer_get(&b, &enc->cipher, sizeof(enc->cipher)); 454 enc->enabled = buffer_get_int(&b); 455 enc->block_size = buffer_get_int(&b); 456 enc->key = buffer_get_string(&b, &enc->key_len); 457 enc->iv = buffer_get_string(&b, &len); 458 if (len != enc->block_size) 459 fatal("%s: bad ivlen: expected %u != %u", __func__, 460 enc->block_size, len); 461 462 if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher) 463 fatal("%s: bad cipher name %s or pointer %p", __func__, 464 enc->name, enc->cipher); 465 466 /* Mac structure */ 467 mac->name = buffer_get_string(&b, NULL); 468 if (mac->name == NULL || mac_init(mac, mac->name) == -1) 469 fatal("%s: can not init mac %s", __func__, mac->name); 470 mac->enabled = buffer_get_int(&b); 471 mac->key = buffer_get_string(&b, &len); 472 if (len > mac->key_len) 473 fatal("%s: bad mac key length: %u > %d", __func__, len, 474 mac->key_len); 475 mac->key_len = len; 476 477 /* Comp structure */ 478 comp->type = buffer_get_int(&b); 479 comp->enabled = buffer_get_int(&b); 480 comp->name = buffer_get_string(&b, NULL); 481 482 len = buffer_len(&b); 483 if (len != 0) 484 error("newkeys_from_blob: remaining bytes in blob %u", len); 485 buffer_free(&b); 486 return (newkey); 487 } 488 489 int 490 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp) 491 { 492 Buffer b; 493 int len; 494 Enc *enc; 495 Mac *mac; 496 Comp *comp; 497 Newkeys *newkey = newkeys[mode]; 498 499 debug3("%s: converting %p", __func__, newkey); 500 501 if (newkey == NULL) { 502 error("%s: newkey == NULL", __func__); 503 return 0; 504 } 505 enc = &newkey->enc; 506 mac = &newkey->mac; 507 comp = &newkey->comp; 508 509 buffer_init(&b); 510 /* Enc structure */ 511 buffer_put_cstring(&b, enc->name); 512 /* The cipher struct is constant and shared, you export pointer */ 513 buffer_append(&b, &enc->cipher, sizeof(enc->cipher)); 514 buffer_put_int(&b, enc->enabled); 515 buffer_put_int(&b, enc->block_size); 516 buffer_put_string(&b, enc->key, enc->key_len); 517 packet_get_keyiv(mode, enc->iv, enc->block_size); 518 buffer_put_string(&b, enc->iv, enc->block_size); 519 520 /* Mac structure */ 521 buffer_put_cstring(&b, mac->name); 522 buffer_put_int(&b, mac->enabled); 523 buffer_put_string(&b, mac->key, mac->key_len); 524 525 /* Comp structure */ 526 buffer_put_int(&b, comp->type); 527 buffer_put_int(&b, comp->enabled); 528 buffer_put_cstring(&b, comp->name); 529 530 len = buffer_len(&b); 531 if (lenp != NULL) 532 *lenp = len; 533 if (blobp != NULL) { 534 *blobp = xmalloc(len); 535 memcpy(*blobp, buffer_ptr(&b), len); 536 } 537 memset(buffer_ptr(&b), 0, len); 538 buffer_free(&b); 539 return len; 540 } 541 542 static void 543 mm_send_kex(Buffer *m, Kex *kex) 544 { 545 buffer_put_string(m, kex->session_id, kex->session_id_len); 546 buffer_put_int(m, kex->we_need); 547 buffer_put_int(m, kex->hostkey_type); 548 buffer_put_int(m, kex->kex_type); 549 buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my)); 550 buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer)); 551 buffer_put_int(m, kex->flags); 552 buffer_put_cstring(m, kex->client_version_string); 553 buffer_put_cstring(m, kex->server_version_string); 554 } 555 556 void 557 mm_send_keystate(struct monitor *monitor) 558 { 559 Buffer m; 560 u_char *blob, *p; 561 u_int bloblen, plen; 562 u_int32_t seqnr, packets; 563 u_int64_t blocks; 564 565 buffer_init(&m); 566 567 if (!compat20) { 568 u_char iv[24]; 569 u_char *key; 570 u_int ivlen, keylen; 571 572 buffer_put_int(&m, packet_get_protocol_flags()); 573 574 buffer_put_int(&m, packet_get_ssh1_cipher()); 575 576 debug3("%s: Sending ssh1 KEY+IV", __func__); 577 keylen = packet_get_encryption_key(NULL); 578 key = xmalloc(keylen+1); /* add 1 if keylen == 0 */ 579 keylen = packet_get_encryption_key(key); 580 buffer_put_string(&m, key, keylen); 581 memset(key, 0, keylen); 582 xfree(key); 583 584 ivlen = packet_get_keyiv_len(MODE_OUT); 585 packet_get_keyiv(MODE_OUT, iv, ivlen); 586 buffer_put_string(&m, iv, ivlen); 587 ivlen = packet_get_keyiv_len(MODE_OUT); 588 packet_get_keyiv(MODE_IN, iv, ivlen); 589 buffer_put_string(&m, iv, ivlen); 590 goto skip; 591 } else { 592 /* Kex for rekeying */ 593 mm_send_kex(&m, *monitor->m_pkex); 594 } 595 596 debug3("%s: Sending new keys: %p %p", 597 __func__, newkeys[MODE_OUT], newkeys[MODE_IN]); 598 599 /* Keys from Kex */ 600 if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen)) 601 fatal("%s: conversion of newkeys failed", __func__); 602 603 buffer_put_string(&m, blob, bloblen); 604 xfree(blob); 605 606 if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen)) 607 fatal("%s: conversion of newkeys failed", __func__); 608 609 buffer_put_string(&m, blob, bloblen); 610 xfree(blob); 611 612 packet_get_state(MODE_OUT, &seqnr, &blocks, &packets); 613 buffer_put_int(&m, seqnr); 614 buffer_put_int64(&m, blocks); 615 buffer_put_int(&m, packets); 616 packet_get_state(MODE_IN, &seqnr, &blocks, &packets); 617 buffer_put_int(&m, seqnr); 618 buffer_put_int64(&m, blocks); 619 buffer_put_int(&m, packets); 620 621 debug3("%s: New keys have been sent", __func__); 622 skip: 623 /* More key context */ 624 plen = packet_get_keycontext(MODE_OUT, NULL); 625 p = xmalloc(plen+1); 626 packet_get_keycontext(MODE_OUT, p); 627 buffer_put_string(&m, p, plen); 628 xfree(p); 629 630 plen = packet_get_keycontext(MODE_IN, NULL); 631 p = xmalloc(plen+1); 632 packet_get_keycontext(MODE_IN, p); 633 buffer_put_string(&m, p, plen); 634 xfree(p); 635 636 /* Compression state */ 637 debug3("%s: Sending compression state", __func__); 638 buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream)); 639 buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream)); 640 641 /* Network I/O buffers */ 642 buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input)); 643 buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output)); 644 645 mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m); 646 debug3("%s: Finished sending state", __func__); 647 648 buffer_free(&m); 649 } 650 651 int 652 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen) 653 { 654 Buffer m; 655 char *p, *msg; 656 int success = 0; 657 658 buffer_init(&m); 659 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m); 660 661 debug3("%s: waiting for MONITOR_ANS_PTY", __func__); 662 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m); 663 664 success = buffer_get_int(&m); 665 if (success == 0) { 666 debug3("%s: pty alloc failed", __func__); 667 buffer_free(&m); 668 return (0); 669 } 670 p = buffer_get_string(&m, NULL); 671 msg = buffer_get_string(&m, NULL); 672 buffer_free(&m); 673 674 strlcpy(namebuf, p, namebuflen); /* Possible truncation */ 675 xfree(p); 676 677 buffer_append(&loginmsg, msg, strlen(msg)); 678 xfree(msg); 679 680 *ptyfd = mm_receive_fd(pmonitor->m_recvfd); 681 *ttyfd = mm_receive_fd(pmonitor->m_recvfd); 682 683 /* Success */ 684 return (1); 685 } 686 687 void 688 mm_session_pty_cleanup2(Session *s) 689 { 690 Buffer m; 691 692 if (s->ttyfd == -1) 693 return; 694 buffer_init(&m); 695 buffer_put_cstring(&m, s->tty); 696 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m); 697 buffer_free(&m); 698 699 /* closed dup'ed master */ 700 if (close(s->ptymaster) < 0) 701 error("close(s->ptymaster): %s", strerror(errno)); 702 703 /* unlink pty from session */ 704 s->ttyfd = -1; 705 } 706 707 #ifdef USE_PAM 708 void 709 mm_start_pam(Authctxt *authctxt) 710 { 711 Buffer m; 712 713 debug3("%s entering", __func__); 714 if (!options.use_pam) 715 fatal("UsePAM=no, but ended up in %s anyway", __func__); 716 717 buffer_init(&m); 718 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m); 719 720 buffer_free(&m); 721 } 722 723 u_int 724 mm_do_pam_account(void) 725 { 726 Buffer m; 727 u_int ret; 728 char *msg; 729 730 debug3("%s entering", __func__); 731 if (!options.use_pam) 732 fatal("UsePAM=no, but ended up in %s anyway", __func__); 733 734 buffer_init(&m); 735 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m); 736 737 mm_request_receive_expect(pmonitor->m_recvfd, 738 MONITOR_ANS_PAM_ACCOUNT, &m); 739 ret = buffer_get_int(&m); 740 msg = buffer_get_string(&m, NULL); 741 buffer_append(&loginmsg, msg, strlen(msg)); 742 xfree(msg); 743 744 buffer_free(&m); 745 746 debug3("%s returning %d", __func__, ret); 747 748 return (ret); 749 } 750 751 void * 752 mm_sshpam_init_ctx(Authctxt *authctxt) 753 { 754 Buffer m; 755 int success; 756 757 debug3("%s", __func__); 758 buffer_init(&m); 759 buffer_put_cstring(&m, authctxt->user); 760 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m); 761 debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__); 762 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m); 763 success = buffer_get_int(&m); 764 if (success == 0) { 765 debug3("%s: pam_init_ctx failed", __func__); 766 buffer_free(&m); 767 return (NULL); 768 } 769 buffer_free(&m); 770 return (authctxt); 771 } 772 773 int 774 mm_sshpam_query(void *ctx, char **name, char **info, 775 u_int *num, char ***prompts, u_int **echo_on) 776 { 777 Buffer m; 778 u_int i; 779 int ret; 780 781 debug3("%s", __func__); 782 buffer_init(&m); 783 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m); 784 debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__); 785 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m); 786 ret = buffer_get_int(&m); 787 debug3("%s: pam_query returned %d", __func__, ret); 788 *name = buffer_get_string(&m, NULL); 789 *info = buffer_get_string(&m, NULL); 790 *num = buffer_get_int(&m); 791 if (*num > PAM_MAX_NUM_MSG) 792 fatal("%s: recieved %u PAM messages, expected <= %u", 793 __func__, *num, PAM_MAX_NUM_MSG); 794 *prompts = xcalloc((*num + 1), sizeof(char *)); 795 *echo_on = xcalloc((*num + 1), sizeof(u_int)); 796 for (i = 0; i < *num; ++i) { 797 (*prompts)[i] = buffer_get_string(&m, NULL); 798 (*echo_on)[i] = buffer_get_int(&m); 799 } 800 buffer_free(&m); 801 return (ret); 802 } 803 804 int 805 mm_sshpam_respond(void *ctx, u_int num, char **resp) 806 { 807 Buffer m; 808 u_int i; 809 int ret; 810 811 debug3("%s", __func__); 812 buffer_init(&m); 813 buffer_put_int(&m, num); 814 for (i = 0; i < num; ++i) 815 buffer_put_cstring(&m, resp[i]); 816 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m); 817 debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__); 818 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m); 819 ret = buffer_get_int(&m); 820 debug3("%s: pam_respond returned %d", __func__, ret); 821 buffer_free(&m); 822 return (ret); 823 } 824 825 void 826 mm_sshpam_free_ctx(void *ctxtp) 827 { 828 Buffer m; 829 830 debug3("%s", __func__); 831 buffer_init(&m); 832 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m); 833 debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__); 834 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m); 835 buffer_free(&m); 836 } 837 #endif /* USE_PAM */ 838 839 /* Request process termination */ 840 841 void 842 mm_terminate(void) 843 { 844 Buffer m; 845 846 buffer_init(&m); 847 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m); 848 buffer_free(&m); 849 } 850 851 int 852 mm_ssh1_session_key(BIGNUM *num) 853 { 854 int rsafail; 855 Buffer m; 856 857 buffer_init(&m); 858 buffer_put_bignum2(&m, num); 859 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m); 860 861 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m); 862 863 rsafail = buffer_get_int(&m); 864 buffer_get_bignum2(&m, num); 865 866 buffer_free(&m); 867 868 return (rsafail); 869 } 870 871 static void 872 mm_chall_setup(char **name, char **infotxt, u_int *numprompts, 873 char ***prompts, u_int **echo_on) 874 { 875 *name = xstrdup(""); 876 *infotxt = xstrdup(""); 877 *numprompts = 1; 878 *prompts = xcalloc(*numprompts, sizeof(char *)); 879 *echo_on = xcalloc(*numprompts, sizeof(u_int)); 880 (*echo_on)[0] = 0; 881 } 882 883 int 884 mm_bsdauth_query(void *ctx, char **name, char **infotxt, 885 u_int *numprompts, char ***prompts, u_int **echo_on) 886 { 887 Buffer m; 888 u_int success; 889 char *challenge; 890 891 debug3("%s: entering", __func__); 892 893 buffer_init(&m); 894 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m); 895 896 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY, 897 &m); 898 success = buffer_get_int(&m); 899 if (success == 0) { 900 debug3("%s: no challenge", __func__); 901 buffer_free(&m); 902 return (-1); 903 } 904 905 /* Get the challenge, and format the response */ 906 challenge = buffer_get_string(&m, NULL); 907 buffer_free(&m); 908 909 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 910 (*prompts)[0] = challenge; 911 912 debug3("%s: received challenge: %s", __func__, challenge); 913 914 return (0); 915 } 916 917 int 918 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses) 919 { 920 Buffer m; 921 int authok; 922 923 debug3("%s: entering", __func__); 924 if (numresponses != 1) 925 return (-1); 926 927 buffer_init(&m); 928 buffer_put_cstring(&m, responses[0]); 929 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m); 930 931 mm_request_receive_expect(pmonitor->m_recvfd, 932 MONITOR_ANS_BSDAUTHRESPOND, &m); 933 934 authok = buffer_get_int(&m); 935 buffer_free(&m); 936 937 return ((authok == 0) ? -1 : 0); 938 } 939 940 #ifdef SKEY 941 int 942 mm_skey_query(void *ctx, char **name, char **infotxt, 943 u_int *numprompts, char ***prompts, u_int **echo_on) 944 { 945 Buffer m; 946 u_int success; 947 char *challenge; 948 949 debug3("%s: entering", __func__); 950 951 buffer_init(&m); 952 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m); 953 954 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY, 955 &m); 956 success = buffer_get_int(&m); 957 if (success == 0) { 958 debug3("%s: no challenge", __func__); 959 buffer_free(&m); 960 return (-1); 961 } 962 963 /* Get the challenge, and format the response */ 964 challenge = buffer_get_string(&m, NULL); 965 buffer_free(&m); 966 967 debug3("%s: received challenge: %s", __func__, challenge); 968 969 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 970 971 xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT); 972 xfree(challenge); 973 974 return (0); 975 } 976 977 int 978 mm_skey_respond(void *ctx, u_int numresponses, char **responses) 979 { 980 Buffer m; 981 int authok; 982 983 debug3("%s: entering", __func__); 984 if (numresponses != 1) 985 return (-1); 986 987 buffer_init(&m); 988 buffer_put_cstring(&m, responses[0]); 989 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m); 990 991 mm_request_receive_expect(pmonitor->m_recvfd, 992 MONITOR_ANS_SKEYRESPOND, &m); 993 994 authok = buffer_get_int(&m); 995 buffer_free(&m); 996 997 return ((authok == 0) ? -1 : 0); 998 } 999 #endif /* SKEY */ 1000 1001 void 1002 mm_ssh1_session_id(u_char session_id[16]) 1003 { 1004 Buffer m; 1005 int i; 1006 1007 debug3("%s entering", __func__); 1008 1009 buffer_init(&m); 1010 for (i = 0; i < 16; i++) 1011 buffer_put_char(&m, session_id[i]); 1012 1013 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m); 1014 buffer_free(&m); 1015 } 1016 1017 int 1018 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey) 1019 { 1020 Buffer m; 1021 Key *key; 1022 u_char *blob; 1023 u_int blen; 1024 int allowed = 0, have_forced = 0; 1025 1026 debug3("%s entering", __func__); 1027 1028 buffer_init(&m); 1029 buffer_put_bignum2(&m, client_n); 1030 1031 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m); 1032 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m); 1033 1034 allowed = buffer_get_int(&m); 1035 1036 /* fake forced command */ 1037 auth_clear_options(); 1038 have_forced = buffer_get_int(&m); 1039 forced_command = have_forced ? xstrdup("true") : NULL; 1040 1041 if (allowed && rkey != NULL) { 1042 blob = buffer_get_string(&m, &blen); 1043 if ((key = key_from_blob(blob, blen)) == NULL) 1044 fatal("%s: key_from_blob failed", __func__); 1045 *rkey = key; 1046 xfree(blob); 1047 } 1048 mm_send_debug(&m); 1049 buffer_free(&m); 1050 1051 return (allowed); 1052 } 1053 1054 BIGNUM * 1055 mm_auth_rsa_generate_challenge(Key *key) 1056 { 1057 Buffer m; 1058 BIGNUM *challenge; 1059 u_char *blob; 1060 u_int blen; 1061 1062 debug3("%s entering", __func__); 1063 1064 if ((challenge = BN_new()) == NULL) 1065 fatal("%s: BN_new failed", __func__); 1066 1067 key->type = KEY_RSA; /* XXX cheat for key_to_blob */ 1068 if (key_to_blob(key, &blob, &blen) == 0) 1069 fatal("%s: key_to_blob failed", __func__); 1070 key->type = KEY_RSA1; 1071 1072 buffer_init(&m); 1073 buffer_put_string(&m, blob, blen); 1074 xfree(blob); 1075 1076 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m); 1077 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m); 1078 1079 buffer_get_bignum2(&m, challenge); 1080 buffer_free(&m); 1081 1082 return (challenge); 1083 } 1084 1085 int 1086 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16]) 1087 { 1088 Buffer m; 1089 u_char *blob; 1090 u_int blen; 1091 int success = 0; 1092 1093 debug3("%s entering", __func__); 1094 1095 key->type = KEY_RSA; /* XXX cheat for key_to_blob */ 1096 if (key_to_blob(key, &blob, &blen) == 0) 1097 fatal("%s: key_to_blob failed", __func__); 1098 key->type = KEY_RSA1; 1099 1100 buffer_init(&m); 1101 buffer_put_string(&m, blob, blen); 1102 buffer_put_string(&m, response, 16); 1103 xfree(blob); 1104 1105 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m); 1106 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m); 1107 1108 success = buffer_get_int(&m); 1109 buffer_free(&m); 1110 1111 return (success); 1112 } 1113 1114 #ifdef SSH_AUDIT_EVENTS 1115 void 1116 mm_audit_event(ssh_audit_event_t event) 1117 { 1118 Buffer m; 1119 1120 debug3("%s entering", __func__); 1121 1122 buffer_init(&m); 1123 buffer_put_int(&m, event); 1124 1125 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m); 1126 buffer_free(&m); 1127 } 1128 1129 void 1130 mm_audit_run_command(const char *command) 1131 { 1132 Buffer m; 1133 1134 debug3("%s entering command %s", __func__, command); 1135 1136 buffer_init(&m); 1137 buffer_put_cstring(&m, command); 1138 1139 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m); 1140 buffer_free(&m); 1141 } 1142 #endif /* SSH_AUDIT_EVENTS */ 1143 1144 #ifdef GSSAPI 1145 OM_uint32 1146 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid) 1147 { 1148 Buffer m; 1149 OM_uint32 major; 1150 1151 /* Client doesn't get to see the context */ 1152 *ctx = NULL; 1153 1154 buffer_init(&m); 1155 buffer_put_string(&m, goid->elements, goid->length); 1156 1157 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m); 1158 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m); 1159 1160 major = buffer_get_int(&m); 1161 1162 buffer_free(&m); 1163 return (major); 1164 } 1165 1166 OM_uint32 1167 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in, 1168 gss_buffer_desc *out, OM_uint32 *flags) 1169 { 1170 Buffer m; 1171 OM_uint32 major; 1172 u_int len; 1173 1174 buffer_init(&m); 1175 buffer_put_string(&m, in->value, in->length); 1176 1177 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m); 1178 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m); 1179 1180 major = buffer_get_int(&m); 1181 out->value = buffer_get_string(&m, &len); 1182 out->length = len; 1183 if (flags) 1184 *flags = buffer_get_int(&m); 1185 1186 buffer_free(&m); 1187 1188 return (major); 1189 } 1190 1191 OM_uint32 1192 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic) 1193 { 1194 Buffer m; 1195 OM_uint32 major; 1196 1197 buffer_init(&m); 1198 buffer_put_string(&m, gssbuf->value, gssbuf->length); 1199 buffer_put_string(&m, gssmic->value, gssmic->length); 1200 1201 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m); 1202 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC, 1203 &m); 1204 1205 major = buffer_get_int(&m); 1206 buffer_free(&m); 1207 return(major); 1208 } 1209 1210 int 1211 mm_ssh_gssapi_userok(char *user) 1212 { 1213 Buffer m; 1214 int authenticated = 0; 1215 1216 buffer_init(&m); 1217 1218 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m); 1219 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK, 1220 &m); 1221 1222 authenticated = buffer_get_int(&m); 1223 1224 buffer_free(&m); 1225 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not "); 1226 return (authenticated); 1227 } 1228 #endif /* GSSAPI */ 1229