1 /* $NetBSD: monitor_wrap.c,v 1.14 2016/03/11 01:55:00 christos Exp $ */ 2 /* $OpenBSD: monitor_wrap.c,v 1.87 2016/01/14 16:17:40 markus Exp $ */ 3 4 /* 5 * Copyright 2002 Niels Provos <provos@citi.umich.edu> 6 * Copyright 2002 Markus Friedl <markus@openbsd.org> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include "includes.h" 31 __RCSID("$NetBSD: monitor_wrap.c,v 1.14 2016/03/11 01:55:00 christos Exp $"); 32 #include <sys/types.h> 33 #include <sys/uio.h> 34 #include <sys/queue.h> 35 36 #include <errno.h> 37 #include <pwd.h> 38 #include <signal.h> 39 #include <stdio.h> 40 #include <string.h> 41 #include <unistd.h> 42 43 #ifdef WITH_OPENSSL 44 #include <openssl/bn.h> 45 #include <openssl/dh.h> 46 #endif 47 48 #include "xmalloc.h" 49 #include "ssh.h" 50 #ifdef WITH_OPENSSL 51 #include "dh.h" 52 #endif 53 #include "buffer.h" 54 #include "key.h" 55 #include "cipher.h" 56 #include "kex.h" 57 #include "hostfile.h" 58 #include "auth.h" 59 #include "auth-options.h" 60 #include "packet.h" 61 #include "mac.h" 62 #include "log.h" 63 #include <zlib.h> 64 #include "monitor.h" 65 #ifdef GSSAPI 66 #include "ssh-gss.h" 67 #endif 68 #include "monitor_wrap.h" 69 #include "atomicio.h" 70 #include "monitor_fdpass.h" 71 #ifdef USE_PAM 72 #include "misc.h" 73 #include "servconf.h" 74 #include <security/pam_appl.h> 75 #endif 76 #include "misc.h" 77 #include "uuencode.h" 78 79 #include "channels.h" 80 #include "session.h" 81 #include "servconf.h" 82 83 #include "ssherr.h" 84 85 /* Imports */ 86 extern int compat20; 87 extern z_stream incoming_stream; 88 extern z_stream outgoing_stream; 89 extern struct monitor *pmonitor; 90 extern Buffer loginmsg; 91 extern ServerOptions options; 92 93 void 94 mm_log_handler(LogLevel level, const char *msg, void *ctx) 95 { 96 Buffer log_msg; 97 struct monitor *mon = (struct monitor *)ctx; 98 99 if (mon->m_log_sendfd == -1) 100 fatal("%s: no log channel", __func__); 101 102 buffer_init(&log_msg); 103 /* 104 * Placeholder for packet length. Will be filled in with the actual 105 * packet length once the packet has been constucted. This saves 106 * fragile math. 107 */ 108 buffer_put_int(&log_msg, 0); 109 110 buffer_put_int(&log_msg, level); 111 buffer_put_cstring(&log_msg, msg); 112 put_u32(buffer_ptr(&log_msg), buffer_len(&log_msg) - 4); 113 if (atomicio(vwrite, mon->m_log_sendfd, buffer_ptr(&log_msg), 114 buffer_len(&log_msg)) != buffer_len(&log_msg)) 115 fatal("%s: write: %s", __func__, strerror(errno)); 116 buffer_free(&log_msg); 117 } 118 119 int 120 mm_is_monitor(void) 121 { 122 /* 123 * m_pid is only set in the privileged part, and 124 * points to the unprivileged child. 125 */ 126 return (pmonitor && pmonitor->m_pid > 0); 127 } 128 129 void 130 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m) 131 { 132 u_int mlen = buffer_len(m); 133 u_char buf[5]; 134 135 debug3("%s entering: type %d", __func__, type); 136 137 put_u32(buf, mlen + 1); 138 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */ 139 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf)) 140 fatal("%s: write: %s", __func__, strerror(errno)); 141 if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen) 142 fatal("%s: write: %s", __func__, strerror(errno)); 143 } 144 145 void 146 mm_request_receive(int sock, Buffer *m) 147 { 148 u_char buf[4]; 149 u_int msg_len; 150 151 debug3("%s entering", __func__); 152 153 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) { 154 if (errno == EPIPE) 155 cleanup_exit(255); 156 fatal("%s: read: %s", __func__, strerror(errno)); 157 } 158 msg_len = get_u32(buf); 159 if (msg_len > 256 * 1024) 160 fatal("%s: read: bad msg_len %d", __func__, msg_len); 161 buffer_clear(m); 162 buffer_append_space(m, msg_len); 163 if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len) 164 fatal("%s: read: %s", __func__, strerror(errno)); 165 } 166 167 void 168 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m) 169 { 170 u_char rtype; 171 172 debug3("%s entering: type %d", __func__, type); 173 174 mm_request_receive(sock, m); 175 rtype = buffer_get_char(m); 176 if (rtype != type) 177 fatal("%s: read: rtype %d != type %d", __func__, 178 rtype, type); 179 } 180 181 #ifdef WITH_OPENSSL 182 DH * 183 mm_choose_dh(int min, int nbits, int max) 184 { 185 BIGNUM *p, *g; 186 int success = 0; 187 Buffer m; 188 189 buffer_init(&m); 190 buffer_put_int(&m, min); 191 buffer_put_int(&m, nbits); 192 buffer_put_int(&m, max); 193 194 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m); 195 196 debug3("%s: waiting for MONITOR_ANS_MODULI", __func__); 197 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m); 198 199 success = buffer_get_char(&m); 200 if (success == 0) 201 fatal("%s: MONITOR_ANS_MODULI failed", __func__); 202 203 if ((p = BN_new()) == NULL) 204 fatal("%s: BN_new failed", __func__); 205 if ((g = BN_new()) == NULL) 206 fatal("%s: BN_new failed", __func__); 207 buffer_get_bignum2(&m, p); 208 buffer_get_bignum2(&m, g); 209 210 debug3("%s: remaining %d", __func__, buffer_len(&m)); 211 buffer_free(&m); 212 213 return (dh_new_group(g, p)); 214 } 215 #endif 216 217 int 218 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, 219 const u_char *data, u_int datalen, const char *hostkey_alg) 220 { 221 struct kex *kex = *pmonitor->m_pkex; 222 Buffer m; 223 224 debug3("%s entering", __func__); 225 226 buffer_init(&m); 227 buffer_put_int(&m, kex->host_key_index(key, 0, active_state)); 228 buffer_put_string(&m, data, datalen); 229 buffer_put_cstring(&m, hostkey_alg); 230 231 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m); 232 233 debug3("%s: waiting for MONITOR_ANS_SIGN", __func__); 234 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m); 235 *sigp = buffer_get_string(&m, lenp); 236 buffer_free(&m); 237 238 return (0); 239 } 240 241 struct passwd * 242 mm_getpwnamallow(const char *username) 243 { 244 Buffer m; 245 struct passwd *pw; 246 u_int len, i; 247 ServerOptions *newopts; 248 249 debug3("%s entering", __func__); 250 251 buffer_init(&m); 252 buffer_put_cstring(&m, username); 253 254 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m); 255 256 debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__); 257 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m); 258 259 if (buffer_get_char(&m) == 0) { 260 pw = NULL; 261 goto out; 262 } 263 pw = buffer_get_string(&m, &len); 264 if (len != sizeof(struct passwd)) 265 fatal("%s: struct passwd size mismatch", __func__); 266 pw->pw_name = buffer_get_string(&m, NULL); 267 pw->pw_passwd = buffer_get_string(&m, NULL); 268 pw->pw_gecos = buffer_get_string(&m, NULL); 269 pw->pw_class = buffer_get_string(&m, NULL); 270 pw->pw_dir = buffer_get_string(&m, NULL); 271 pw->pw_shell = buffer_get_string(&m, NULL); 272 273 out: 274 /* copy options block as a Match directive may have changed some */ 275 newopts = buffer_get_string(&m, &len); 276 if (len != sizeof(*newopts)) 277 fatal("%s: option block size mismatch", __func__); 278 279 #define M_CP_STROPT(x) do { \ 280 if (newopts->x != NULL) \ 281 newopts->x = buffer_get_string(&m, NULL); \ 282 } while (0) 283 #define M_CP_STRARRAYOPT(x, nx) do { \ 284 for (i = 0; i < newopts->nx; i++) \ 285 newopts->x[i] = buffer_get_string(&m, NULL); \ 286 } while (0) 287 /* See comment in servconf.h */ 288 COPY_MATCH_STRING_OPTS(); 289 #undef M_CP_STROPT 290 #undef M_CP_STRARRAYOPT 291 292 copy_set_server_options(&options, newopts, 1); 293 free(newopts); 294 295 buffer_free(&m); 296 297 return (pw); 298 } 299 300 char * 301 mm_auth2_read_banner(void) 302 { 303 Buffer m; 304 char *banner; 305 306 debug3("%s entering", __func__); 307 308 buffer_init(&m); 309 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m); 310 buffer_clear(&m); 311 312 mm_request_receive_expect(pmonitor->m_recvfd, 313 MONITOR_ANS_AUTH2_READ_BANNER, &m); 314 banner = buffer_get_string(&m, NULL); 315 buffer_free(&m); 316 317 /* treat empty banner as missing banner */ 318 if (strlen(banner) == 0) { 319 free(banner); 320 banner = NULL; 321 } 322 return (banner); 323 } 324 325 /* Inform the privileged process about service and style */ 326 327 void 328 mm_inform_authserv(char *service, char *style) 329 { 330 Buffer m; 331 332 debug3("%s entering", __func__); 333 334 buffer_init(&m); 335 buffer_put_cstring(&m, service); 336 buffer_put_cstring(&m, style ? style : ""); 337 338 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m); 339 340 buffer_free(&m); 341 } 342 343 /* Do the password authentication */ 344 int 345 mm_auth_password(Authctxt *authctxt, const char *password) 346 { 347 Buffer m; 348 int authenticated = 0; 349 350 debug3("%s entering", __func__); 351 352 buffer_init(&m); 353 buffer_put_cstring(&m, password); 354 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m); 355 356 debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__); 357 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m); 358 359 authenticated = buffer_get_int(&m); 360 361 buffer_free(&m); 362 363 debug3("%s: user %sauthenticated", 364 __func__, authenticated ? "" : "not "); 365 return (authenticated); 366 } 367 368 int 369 mm_user_key_allowed(struct passwd *pw, Key *key, int pubkey_auth_attempt) 370 { 371 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key, 372 pubkey_auth_attempt)); 373 } 374 375 int 376 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host, 377 Key *key) 378 { 379 return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0)); 380 } 381 382 int 383 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user, 384 char *host, Key *key) 385 { 386 int ret; 387 388 key->type = KEY_RSA; /* XXX hack for key_to_blob */ 389 ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key, 0); 390 key->type = KEY_RSA1; 391 return (ret); 392 } 393 394 int 395 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key, 396 int pubkey_auth_attempt) 397 { 398 Buffer m; 399 u_char *blob; 400 u_int len; 401 int allowed = 0, have_forced = 0; 402 403 debug3("%s entering", __func__); 404 405 /* Convert the key to a blob and the pass it over */ 406 if (!key_to_blob(key, &blob, &len)) 407 return (0); 408 409 buffer_init(&m); 410 buffer_put_int(&m, type); 411 buffer_put_cstring(&m, user ? user : ""); 412 buffer_put_cstring(&m, host ? host : ""); 413 buffer_put_string(&m, blob, len); 414 buffer_put_int(&m, pubkey_auth_attempt); 415 free(blob); 416 417 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m); 418 419 debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__); 420 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m); 421 422 allowed = buffer_get_int(&m); 423 424 /* fake forced command */ 425 auth_clear_options(); 426 have_forced = buffer_get_int(&m); 427 forced_command = have_forced ? xstrdup("true") : NULL; 428 429 buffer_free(&m); 430 431 return (allowed); 432 } 433 434 /* 435 * This key verify needs to send the key type along, because the 436 * privileged parent makes the decision if the key is allowed 437 * for authentication. 438 */ 439 440 int 441 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen) 442 { 443 Buffer m; 444 u_char *blob; 445 u_int len; 446 int verified = 0; 447 448 debug3("%s entering", __func__); 449 450 /* Convert the key to a blob and the pass it over */ 451 if (!key_to_blob(key, &blob, &len)) 452 return (0); 453 454 buffer_init(&m); 455 buffer_put_string(&m, blob, len); 456 buffer_put_string(&m, sig, siglen); 457 buffer_put_string(&m, data, datalen); 458 free(blob); 459 460 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m); 461 462 debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__); 463 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m); 464 465 verified = buffer_get_int(&m); 466 467 buffer_free(&m); 468 469 return (verified); 470 } 471 472 void 473 mm_send_keystate(struct monitor *monitor) 474 { 475 struct ssh *ssh = active_state; /* XXX */ 476 struct sshbuf *m; 477 int r; 478 479 if ((m = sshbuf_new()) == NULL) 480 fatal("%s: sshbuf_new failed", __func__); 481 if ((r = ssh_packet_get_state(ssh, m)) != 0) 482 fatal("%s: get_state failed: %s", 483 __func__, ssh_err(r)); 484 mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m); 485 debug3("%s: Finished sending state", __func__); 486 sshbuf_free(m); 487 } 488 489 int 490 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen) 491 { 492 Buffer m; 493 char *p, *msg; 494 int success = 0, tmp1 = -1, tmp2 = -1; 495 496 /* Kludge: ensure there are fds free to receive the pty/tty */ 497 if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 || 498 (tmp2 = dup(pmonitor->m_recvfd)) == -1) { 499 error("%s: cannot allocate fds for pty", __func__); 500 if (tmp1 > 0) 501 close(tmp1); 502 if (tmp2 > 0) 503 close(tmp2); 504 return 0; 505 } 506 close(tmp1); 507 close(tmp2); 508 509 buffer_init(&m); 510 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m); 511 512 debug3("%s: waiting for MONITOR_ANS_PTY", __func__); 513 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m); 514 515 success = buffer_get_int(&m); 516 if (success == 0) { 517 debug3("%s: pty alloc failed", __func__); 518 buffer_free(&m); 519 return (0); 520 } 521 p = buffer_get_string(&m, NULL); 522 msg = buffer_get_string(&m, NULL); 523 buffer_free(&m); 524 525 strlcpy(namebuf, p, namebuflen); /* Possible truncation */ 526 free(p); 527 528 buffer_append(&loginmsg, msg, strlen(msg)); 529 free(msg); 530 531 if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 || 532 (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1) 533 fatal("%s: receive fds failed", __func__); 534 535 /* Success */ 536 return (1); 537 } 538 539 void 540 mm_session_pty_cleanup2(Session *s) 541 { 542 Buffer m; 543 544 if (s->ttyfd == -1) 545 return; 546 buffer_init(&m); 547 buffer_put_cstring(&m, s->tty); 548 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m); 549 buffer_free(&m); 550 551 /* closed dup'ed master */ 552 if (s->ptymaster != -1 && close(s->ptymaster) < 0) 553 error("close(s->ptymaster/%d): %s", 554 s->ptymaster, strerror(errno)); 555 556 /* unlink pty from session */ 557 s->ttyfd = -1; 558 } 559 560 #ifdef USE_PAM 561 void 562 mm_start_pam(Authctxt *authctxt) 563 { 564 Buffer m; 565 566 debug3("%s entering", __func__); 567 if (!options.use_pam) 568 fatal("UsePAM=no, but ended up in %s anyway", __func__); 569 570 buffer_init(&m); 571 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m); 572 573 buffer_free(&m); 574 } 575 576 u_int 577 mm_do_pam_account(void) 578 { 579 Buffer m; 580 u_int ret; 581 char *msg; 582 583 debug3("%s entering", __func__); 584 if (!options.use_pam) 585 fatal("UsePAM=no, but ended up in %s anyway", __func__); 586 587 buffer_init(&m); 588 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m); 589 590 mm_request_receive_expect(pmonitor->m_recvfd, 591 MONITOR_ANS_PAM_ACCOUNT, &m); 592 ret = buffer_get_int(&m); 593 msg = buffer_get_string(&m, NULL); 594 buffer_append(&loginmsg, msg, strlen(msg)); 595 free(msg); 596 597 buffer_free(&m); 598 599 debug3("%s returning %d", __func__, ret); 600 601 return (ret); 602 } 603 604 void * 605 mm_sshpam_init_ctx(Authctxt *authctxt) 606 { 607 Buffer m; 608 int success; 609 610 debug3("%s", __func__); 611 buffer_init(&m); 612 buffer_put_cstring(&m, authctxt->user); 613 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m); 614 debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__); 615 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m); 616 success = buffer_get_int(&m); 617 if (success == 0) { 618 debug3("%s: pam_init_ctx failed", __func__); 619 buffer_free(&m); 620 return (NULL); 621 } 622 buffer_free(&m); 623 return (authctxt); 624 } 625 626 int 627 mm_sshpam_query(void *ctx, char **name, char **info, 628 u_int *num, char ***prompts, u_int **echo_on) 629 { 630 Buffer m; 631 u_int i; 632 int ret; 633 634 debug3("%s", __func__); 635 buffer_init(&m); 636 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m); 637 debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__); 638 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m); 639 ret = buffer_get_int(&m); 640 debug3("%s: pam_query returned %d", __func__, ret); 641 *name = buffer_get_string(&m, NULL); 642 *info = buffer_get_string(&m, NULL); 643 *num = buffer_get_int(&m); 644 if (*num > PAM_MAX_NUM_MSG) 645 fatal("%s: received %u PAM messages, expected <= %u", 646 __func__, *num, PAM_MAX_NUM_MSG); 647 *prompts = xcalloc((*num + 1), sizeof(char *)); 648 *echo_on = xcalloc((*num + 1), sizeof(u_int)); 649 for (i = 0; i < *num; ++i) { 650 (*prompts)[i] = buffer_get_string(&m, NULL); 651 (*echo_on)[i] = buffer_get_int(&m); 652 } 653 buffer_free(&m); 654 return (ret); 655 } 656 657 int 658 mm_sshpam_respond(void *ctx, u_int num, char **resp) 659 { 660 Buffer m; 661 u_int i; 662 int ret; 663 664 debug3("%s", __func__); 665 buffer_init(&m); 666 buffer_put_int(&m, num); 667 for (i = 0; i < num; ++i) 668 buffer_put_cstring(&m, resp[i]); 669 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m); 670 debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__); 671 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m); 672 ret = buffer_get_int(&m); 673 debug3("%s: pam_respond returned %d", __func__, ret); 674 buffer_free(&m); 675 return (ret); 676 } 677 678 void 679 mm_sshpam_free_ctx(void *ctxtp) 680 { 681 Buffer m; 682 683 debug3("%s", __func__); 684 buffer_init(&m); 685 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m); 686 debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__); 687 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m); 688 buffer_free(&m); 689 } 690 #endif /* USE_PAM */ 691 692 /* Request process termination */ 693 694 void 695 mm_terminate(void) 696 { 697 Buffer m; 698 699 buffer_init(&m); 700 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m); 701 buffer_free(&m); 702 } 703 704 #ifdef WITH_SSH1 705 int 706 mm_ssh1_session_key(BIGNUM *num) 707 { 708 int rsafail; 709 Buffer m; 710 711 buffer_init(&m); 712 buffer_put_bignum2(&m, num); 713 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m); 714 715 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m); 716 717 rsafail = buffer_get_int(&m); 718 buffer_get_bignum2(&m, num); 719 720 buffer_free(&m); 721 722 return (rsafail); 723 } 724 #endif 725 726 #if defined(BSD_AUTH) || defined(SKEY) 727 static void 728 mm_chall_setup(char **name, char **infotxt, u_int *numprompts, 729 char ***prompts, u_int **echo_on) 730 { 731 *name = xstrdup(""); 732 *infotxt = xstrdup(""); 733 *numprompts = 1; 734 *prompts = xcalloc(*numprompts, sizeof(char *)); 735 *echo_on = xcalloc(*numprompts, sizeof(u_int)); 736 (*echo_on)[0] = 0; 737 } 738 #endif 739 740 #ifdef BSD_AUTH 741 int 742 mm_bsdauth_query(void *ctx, char **name, char **infotxt, 743 u_int *numprompts, char ***prompts, u_int **echo_on) 744 { 745 Buffer m; 746 u_int success; 747 char *challenge; 748 749 debug3("%s: entering", __func__); 750 751 buffer_init(&m); 752 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m); 753 754 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY, 755 &m); 756 success = buffer_get_int(&m); 757 if (success == 0) { 758 debug3("%s: no challenge", __func__); 759 buffer_free(&m); 760 return (-1); 761 } 762 763 /* Get the challenge, and format the response */ 764 challenge = buffer_get_string(&m, NULL); 765 buffer_free(&m); 766 767 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 768 (*prompts)[0] = challenge; 769 770 debug3("%s: received challenge: %s", __func__, challenge); 771 772 return (0); 773 } 774 775 int 776 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses) 777 { 778 Buffer m; 779 int authok; 780 781 debug3("%s: entering", __func__); 782 if (numresponses != 1) 783 return (-1); 784 785 buffer_init(&m); 786 buffer_put_cstring(&m, responses[0]); 787 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m); 788 789 mm_request_receive_expect(pmonitor->m_recvfd, 790 MONITOR_ANS_BSDAUTHRESPOND, &m); 791 792 authok = buffer_get_int(&m); 793 buffer_free(&m); 794 795 return ((authok == 0) ? -1 : 0); 796 } 797 #endif 798 799 #ifdef SKEY 800 int 801 mm_skey_query(void *ctx, char **name, char **infotxt, 802 u_int *numprompts, char ***prompts, u_int **echo_on) 803 { 804 Buffer m; 805 u_int success; 806 char *challenge; 807 808 debug3("%s: entering", __func__); 809 810 buffer_init(&m); 811 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m); 812 813 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY, 814 &m); 815 success = buffer_get_int(&m); 816 if (success == 0) { 817 debug3("%s: no challenge", __func__); 818 buffer_free(&m); 819 return (-1); 820 } 821 822 /* Get the challenge, and format the response */ 823 challenge = buffer_get_string(&m, NULL); 824 buffer_free(&m); 825 826 debug3("%s: received challenge: %s", __func__, challenge); 827 828 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 829 830 xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT); 831 free(challenge); 832 833 return (0); 834 } 835 836 int 837 mm_skey_respond(void *ctx, u_int numresponses, char **responses) 838 { 839 Buffer m; 840 int authok; 841 842 debug3("%s: entering", __func__); 843 if (numresponses != 1) 844 return (-1); 845 846 buffer_init(&m); 847 buffer_put_cstring(&m, responses[0]); 848 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m); 849 850 mm_request_receive_expect(pmonitor->m_recvfd, 851 MONITOR_ANS_SKEYRESPOND, &m); 852 853 authok = buffer_get_int(&m); 854 buffer_free(&m); 855 856 return ((authok == 0) ? -1 : 0); 857 } 858 #endif /* SKEY */ 859 860 void 861 mm_ssh1_session_id(u_char session_id[16]) 862 { 863 Buffer m; 864 int i; 865 866 debug3("%s entering", __func__); 867 868 buffer_init(&m); 869 for (i = 0; i < 16; i++) 870 buffer_put_char(&m, session_id[i]); 871 872 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m); 873 buffer_free(&m); 874 } 875 876 #ifdef WITH_SSH1 877 int 878 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey) 879 { 880 Buffer m; 881 Key *key; 882 u_char *blob; 883 u_int blen; 884 int allowed = 0, have_forced = 0; 885 886 debug3("%s entering", __func__); 887 888 buffer_init(&m); 889 buffer_put_bignum2(&m, client_n); 890 891 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m); 892 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m); 893 894 allowed = buffer_get_int(&m); 895 896 /* fake forced command */ 897 auth_clear_options(); 898 have_forced = buffer_get_int(&m); 899 forced_command = have_forced ? xstrdup("true") : NULL; 900 901 if (allowed && rkey != NULL) { 902 blob = buffer_get_string(&m, &blen); 903 if ((key = key_from_blob(blob, blen)) == NULL) 904 fatal("%s: key_from_blob failed", __func__); 905 *rkey = key; 906 free(blob); 907 } 908 buffer_free(&m); 909 910 return (allowed); 911 } 912 913 BIGNUM * 914 mm_auth_rsa_generate_challenge(Key *key) 915 { 916 Buffer m; 917 BIGNUM *challenge; 918 u_char *blob; 919 u_int blen; 920 921 debug3("%s entering", __func__); 922 923 if ((challenge = BN_new()) == NULL) 924 fatal("%s: BN_new failed", __func__); 925 926 key->type = KEY_RSA; /* XXX cheat for key_to_blob */ 927 if (key_to_blob(key, &blob, &blen) == 0) 928 fatal("%s: key_to_blob failed", __func__); 929 key->type = KEY_RSA1; 930 931 buffer_init(&m); 932 buffer_put_string(&m, blob, blen); 933 free(blob); 934 935 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m); 936 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m); 937 938 buffer_get_bignum2(&m, challenge); 939 buffer_free(&m); 940 941 return (challenge); 942 } 943 944 int 945 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16]) 946 { 947 Buffer m; 948 u_char *blob; 949 u_int blen; 950 int success = 0; 951 952 debug3("%s entering", __func__); 953 954 key->type = KEY_RSA; /* XXX cheat for key_to_blob */ 955 if (key_to_blob(key, &blob, &blen) == 0) 956 fatal("%s: key_to_blob failed", __func__); 957 key->type = KEY_RSA1; 958 959 buffer_init(&m); 960 buffer_put_string(&m, blob, blen); 961 buffer_put_string(&m, response, 16); 962 free(blob); 963 964 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m); 965 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m); 966 967 success = buffer_get_int(&m); 968 buffer_free(&m); 969 970 return (success); 971 } 972 #endif 973 974 #ifdef GSSAPI 975 OM_uint32 976 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid) 977 { 978 Buffer m; 979 OM_uint32 major; 980 981 /* Client doesn't get to see the context */ 982 *ctx = NULL; 983 984 buffer_init(&m); 985 buffer_put_string(&m, goid->elements, goid->length); 986 987 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m); 988 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m); 989 990 major = buffer_get_int(&m); 991 992 buffer_free(&m); 993 return (major); 994 } 995 996 OM_uint32 997 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in, 998 gss_buffer_desc *out, OM_uint32 *flags) 999 { 1000 Buffer m; 1001 OM_uint32 major; 1002 u_int len; 1003 1004 buffer_init(&m); 1005 buffer_put_string(&m, in->value, in->length); 1006 1007 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m); 1008 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m); 1009 1010 major = buffer_get_int(&m); 1011 out->value = buffer_get_string(&m, &len); 1012 out->length = len; 1013 if (flags) 1014 *flags = buffer_get_int(&m); 1015 1016 buffer_free(&m); 1017 1018 return (major); 1019 } 1020 1021 OM_uint32 1022 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic) 1023 { 1024 Buffer m; 1025 OM_uint32 major; 1026 1027 buffer_init(&m); 1028 buffer_put_string(&m, gssbuf->value, gssbuf->length); 1029 buffer_put_string(&m, gssmic->value, gssmic->length); 1030 1031 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m); 1032 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC, 1033 &m); 1034 1035 major = buffer_get_int(&m); 1036 buffer_free(&m); 1037 return(major); 1038 } 1039 1040 int 1041 mm_ssh_gssapi_userok(char *user) 1042 { 1043 Buffer m; 1044 int authenticated = 0; 1045 1046 buffer_init(&m); 1047 1048 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m); 1049 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK, 1050 &m); 1051 1052 authenticated = buffer_get_int(&m); 1053 1054 buffer_free(&m); 1055 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not "); 1056 return (authenticated); 1057 } 1058 #endif /* GSSAPI */ 1059 1060 #ifdef KRB4 1061 int 1062 mm_auth_krb4(Authctxt *authctxt, void *_auth, char **client, void *_reply) 1063 { 1064 KTEXT auth, reply; 1065 Buffer m; 1066 u_int rlen; 1067 int success = 0; 1068 char *p; 1069 1070 debug3("%s entering", __func__); 1071 auth = _auth; 1072 reply = _reply; 1073 1074 buffer_init(&m); 1075 buffer_put_string(&m, auth->dat, auth->length); 1076 1077 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KRB4, &m); 1078 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KRB4, &m); 1079 1080 success = buffer_get_int(&m); 1081 if (success) { 1082 *client = buffer_get_string(&m, NULL); 1083 p = buffer_get_string(&m, &rlen); 1084 if (rlen >= MAX_KTXT_LEN) 1085 fatal("%s: reply from monitor too large", __func__); 1086 reply->length = rlen; 1087 memcpy(reply->dat, p, rlen); 1088 memset(p, 0, rlen); 1089 free(p); 1090 } 1091 buffer_free(&m); 1092 return (success); 1093 } 1094 #endif 1095 1096 #ifdef KRB5 1097 int 1098 mm_auth_krb5(void *ctx, void *argp, char **userp, void *resp) 1099 { 1100 krb5_data *tkt, *reply; 1101 Buffer m; 1102 int success; 1103 1104 debug3("%s entering", __func__); 1105 tkt = (krb5_data *) argp; 1106 reply = (krb5_data *) resp; 1107 1108 buffer_init(&m); 1109 buffer_put_string(&m, tkt->data, tkt->length); 1110 1111 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KRB5, &m); 1112 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KRB5, &m); 1113 1114 success = buffer_get_int(&m); 1115 if (success) { 1116 u_int len; 1117 1118 *userp = buffer_get_string(&m, NULL); 1119 reply->data = buffer_get_string(&m, &len); 1120 reply->length = len; 1121 } else { 1122 memset(reply, 0, sizeof(*reply)); 1123 *userp = NULL; 1124 } 1125 1126 buffer_free(&m); 1127 return (success); 1128 } 1129 #endif 1130