1 /* $OpenBSD: monitor_wrap.c,v 1.107 2018/07/20 03:46:34 djm 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 <sys/types.h> 29 #include <sys/uio.h> 30 #include <sys/queue.h> 31 32 #include <errno.h> 33 #include <pwd.h> 34 #include <signal.h> 35 #include <stdio.h> 36 #include <string.h> 37 #include <unistd.h> 38 39 #ifdef WITH_OPENSSL 40 #include <openssl/bn.h> 41 #include <openssl/dh.h> 42 #endif 43 44 #include "xmalloc.h" 45 #include "ssh.h" 46 #ifdef WITH_OPENSSL 47 #include "dh.h" 48 #endif 49 #include "sshbuf.h" 50 #include "sshkey.h" 51 #include "cipher.h" 52 #include "kex.h" 53 #include "hostfile.h" 54 #include "auth.h" 55 #include "auth-options.h" 56 #include "packet.h" 57 #include "mac.h" 58 #include "log.h" 59 #include "monitor.h" 60 #ifdef GSSAPI 61 #include "ssh-gss.h" 62 #endif 63 #include "monitor_wrap.h" 64 #include "atomicio.h" 65 #include "monitor_fdpass.h" 66 #include "misc.h" 67 68 #include "channels.h" 69 #include "session.h" 70 #include "servconf.h" 71 72 #include "ssherr.h" 73 74 /* Imports */ 75 extern struct monitor *pmonitor; 76 extern struct sshbuf *loginmsg; 77 extern ServerOptions options; 78 79 void 80 mm_log_handler(LogLevel level, const char *msg, void *ctx) 81 { 82 struct sshbuf *log_msg; 83 struct monitor *mon = (struct monitor *)ctx; 84 int r; 85 size_t len; 86 87 if (mon->m_log_sendfd == -1) 88 fatal("%s: no log channel", __func__); 89 90 if ((log_msg = sshbuf_new()) == NULL) 91 fatal("%s: sshbuf_new failed", __func__); 92 93 if ((r = sshbuf_put_u32(log_msg, 0)) != 0 || /* length; filled below */ 94 (r = sshbuf_put_u32(log_msg, level)) != 0 || 95 (r = sshbuf_put_cstring(log_msg, msg)) != 0) 96 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 97 if ((len = sshbuf_len(log_msg)) < 4 || len > 0xffffffff) 98 fatal("%s: bad length %zu", __func__, len); 99 POKE_U32(sshbuf_mutable_ptr(log_msg), len - 4); 100 if (atomicio(vwrite, mon->m_log_sendfd, 101 sshbuf_mutable_ptr(log_msg), len) != len) 102 fatal("%s: write: %s", __func__, strerror(errno)); 103 sshbuf_free(log_msg); 104 } 105 106 int 107 mm_is_monitor(void) 108 { 109 /* 110 * m_pid is only set in the privileged part, and 111 * points to the unprivileged child. 112 */ 113 return (pmonitor && pmonitor->m_pid > 0); 114 } 115 116 void 117 mm_request_send(int sock, enum monitor_reqtype type, struct sshbuf *m) 118 { 119 size_t mlen = sshbuf_len(m); 120 u_char buf[5]; 121 122 debug3("%s entering: type %d", __func__, type); 123 124 if (mlen >= 0xffffffff) 125 fatal("%s: bad length %zu", __func__, mlen); 126 POKE_U32(buf, mlen + 1); 127 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */ 128 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf)) 129 fatal("%s: write: %s", __func__, strerror(errno)); 130 if (atomicio(vwrite, sock, sshbuf_mutable_ptr(m), mlen) != mlen) 131 fatal("%s: write: %s", __func__, strerror(errno)); 132 } 133 134 void 135 mm_request_receive(int sock, struct sshbuf *m) 136 { 137 u_char buf[4], *p = NULL; 138 u_int msg_len; 139 int r; 140 141 debug3("%s entering", __func__); 142 143 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) { 144 if (errno == EPIPE) 145 cleanup_exit(255); 146 fatal("%s: read: %s", __func__, strerror(errno)); 147 } 148 msg_len = PEEK_U32(buf); 149 if (msg_len > 256 * 1024) 150 fatal("%s: read: bad msg_len %d", __func__, msg_len); 151 sshbuf_reset(m); 152 if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) 153 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 154 if (atomicio(read, sock, p, msg_len) != msg_len) 155 fatal("%s: read: %s", __func__, strerror(errno)); 156 } 157 158 void 159 mm_request_receive_expect(int sock, enum monitor_reqtype type, struct sshbuf *m) 160 { 161 u_char rtype; 162 int r; 163 164 debug3("%s entering: type %d", __func__, type); 165 166 mm_request_receive(sock, m); 167 if ((r = sshbuf_get_u8(m, &rtype)) != 0) 168 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 169 if (rtype != type) 170 fatal("%s: read: rtype %d != type %d", __func__, 171 rtype, type); 172 } 173 174 #ifdef WITH_OPENSSL 175 DH * 176 mm_choose_dh(int min, int nbits, int max) 177 { 178 BIGNUM *p, *g; 179 int r; 180 u_char success = 0; 181 struct sshbuf *m; 182 183 if ((m = sshbuf_new()) == NULL) 184 fatal("%s: sshbuf_new failed", __func__); 185 if ((r = sshbuf_put_u32(m, min)) != 0 || 186 (r = sshbuf_put_u32(m, nbits)) != 0 || 187 (r = sshbuf_put_u32(m, max)) != 0) 188 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 189 190 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, m); 191 192 debug3("%s: waiting for MONITOR_ANS_MODULI", __func__); 193 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, m); 194 195 if ((r = sshbuf_get_u8(m, &success)) != 0) 196 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 197 if (success == 0) 198 fatal("%s: MONITOR_ANS_MODULI failed", __func__); 199 200 if ((p = BN_new()) == NULL) 201 fatal("%s: BN_new failed", __func__); 202 if ((g = BN_new()) == NULL) 203 fatal("%s: BN_new failed", __func__); 204 if ((r = sshbuf_get_bignum2(m, p)) != 0 || 205 (r = sshbuf_get_bignum2(m, g)) != 0) 206 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 207 208 debug3("%s: remaining %zu", __func__, sshbuf_len(m)); 209 sshbuf_free(m); 210 211 return (dh_new_group(g, p)); 212 } 213 #endif 214 215 int 216 mm_sshkey_sign(struct sshkey *key, u_char **sigp, size_t *lenp, 217 const u_char *data, size_t datalen, const char *hostkey_alg, u_int compat) 218 { 219 struct kex *kex = *pmonitor->m_pkex; 220 struct sshbuf *m; 221 u_int ndx = kex->host_key_index(key, 0, active_state); 222 int r; 223 224 debug3("%s entering", __func__); 225 226 if ((m = sshbuf_new()) == NULL) 227 fatal("%s: sshbuf_new failed", __func__); 228 if ((r = sshbuf_put_u32(m, ndx)) != 0 || 229 (r = sshbuf_put_string(m, data, datalen)) != 0 || 230 (r = sshbuf_put_cstring(m, hostkey_alg)) != 0 || 231 (r = sshbuf_put_u32(m, compat)) != 0) 232 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 233 234 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, m); 235 236 debug3("%s: waiting for MONITOR_ANS_SIGN", __func__); 237 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, m); 238 if ((r = sshbuf_get_string(m, sigp, lenp)) != 0) 239 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 240 sshbuf_free(m); 241 242 return (0); 243 } 244 245 struct passwd * 246 mm_getpwnamallow(const char *username) 247 { 248 struct ssh *ssh = active_state; /* XXX */ 249 struct sshbuf *m; 250 struct passwd *pw; 251 size_t len; 252 u_int i; 253 ServerOptions *newopts; 254 int r; 255 u_char ok; 256 const u_char *p; 257 258 debug3("%s entering", __func__); 259 260 if ((m = sshbuf_new()) == NULL) 261 fatal("%s: sshbuf_new failed", __func__); 262 if ((r = sshbuf_put_cstring(m, username)) != 0) 263 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 264 265 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, m); 266 267 debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__); 268 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, m); 269 270 if ((r = sshbuf_get_u8(m, &ok)) != 0) 271 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 272 if (ok == 0) { 273 pw = NULL; 274 goto out; 275 } 276 277 /* XXX don't like passing struct passwd like this */ 278 pw = xcalloc(sizeof(*pw), 1); 279 if ((r = sshbuf_get_string_direct(m, &p, &len)) != 0) 280 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 281 if (len != sizeof(*pw)) 282 fatal("%s: struct passwd size mismatch", __func__); 283 memcpy(pw, p, sizeof(*pw)); 284 285 if ((r = sshbuf_get_cstring(m, &pw->pw_name, NULL)) != 0 || 286 (r = sshbuf_get_cstring(m, &pw->pw_passwd, NULL)) != 0 || 287 (r = sshbuf_get_cstring(m, &pw->pw_gecos, NULL)) != 0 || 288 (r = sshbuf_get_cstring(m, &pw->pw_class, NULL)) != 0 || 289 (r = sshbuf_get_cstring(m, &pw->pw_dir, NULL)) != 0 || 290 (r = sshbuf_get_cstring(m, &pw->pw_shell, NULL)) != 0) 291 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 292 293 out: 294 /* copy options block as a Match directive may have changed some */ 295 if ((r = sshbuf_get_string_direct(m, &p, &len)) != 0) 296 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 297 if (len != sizeof(*newopts)) 298 fatal("%s: option block size mismatch", __func__); 299 newopts = xcalloc(sizeof(*newopts), 1); 300 memcpy(newopts, p, sizeof(*newopts)); 301 302 #define M_CP_STROPT(x) do { \ 303 if (newopts->x != NULL) { \ 304 if ((r = sshbuf_get_cstring(m, \ 305 &newopts->x, NULL)) != 0) \ 306 fatal("%s: buffer error: %s", \ 307 __func__, ssh_err(r)); \ 308 } \ 309 } while (0) 310 #define M_CP_STRARRAYOPT(x, nx) do { \ 311 newopts->x = newopts->nx == 0 ? \ 312 NULL : xcalloc(newopts->nx, sizeof(*newopts->x)); \ 313 for (i = 0; i < newopts->nx; i++) { \ 314 if ((r = sshbuf_get_cstring(m, \ 315 &newopts->x[i], NULL)) != 0) \ 316 fatal("%s: buffer error: %s", \ 317 __func__, ssh_err(r)); \ 318 } \ 319 } while (0) 320 /* See comment in servconf.h */ 321 COPY_MATCH_STRING_OPTS(); 322 #undef M_CP_STROPT 323 #undef M_CP_STRARRAYOPT 324 325 copy_set_server_options(&options, newopts, 1); 326 log_change_level(options.log_level); 327 process_permitopen(ssh, &options); 328 free(newopts); 329 330 sshbuf_free(m); 331 332 return (pw); 333 } 334 335 char * 336 mm_auth2_read_banner(void) 337 { 338 struct sshbuf *m; 339 char *banner; 340 int r; 341 342 debug3("%s entering", __func__); 343 344 if ((m = sshbuf_new()) == NULL) 345 fatal("%s: sshbuf_new failed", __func__); 346 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, m); 347 sshbuf_reset(m); 348 349 mm_request_receive_expect(pmonitor->m_recvfd, 350 MONITOR_ANS_AUTH2_READ_BANNER, m); 351 if ((r = sshbuf_get_cstring(m, &banner, NULL)) != 0) 352 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 353 sshbuf_free(m); 354 355 /* treat empty banner as missing banner */ 356 if (strlen(banner) == 0) { 357 free(banner); 358 banner = NULL; 359 } 360 return (banner); 361 } 362 363 /* Inform the privileged process about service and style */ 364 365 void 366 mm_inform_authserv(char *service, char *style) 367 { 368 struct sshbuf *m; 369 int r; 370 371 debug3("%s entering", __func__); 372 373 if ((m = sshbuf_new()) == NULL) 374 fatal("%s: sshbuf_new failed", __func__); 375 if ((r = sshbuf_put_cstring(m, service)) != 0 || 376 (r = sshbuf_put_cstring(m, style ? style : "")) != 0) 377 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 378 379 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, m); 380 381 sshbuf_free(m); 382 } 383 384 /* Do the password authentication */ 385 int 386 mm_auth_password(struct ssh *ssh, char *password) 387 { 388 struct sshbuf *m; 389 int r, authenticated = 0; 390 391 debug3("%s entering", __func__); 392 393 if ((m = sshbuf_new()) == NULL) 394 fatal("%s: sshbuf_new failed", __func__); 395 if ((r = sshbuf_put_cstring(m, password)) != 0) 396 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 397 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, m); 398 399 debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__); 400 mm_request_receive_expect(pmonitor->m_recvfd, 401 MONITOR_ANS_AUTHPASSWORD, m); 402 403 if ((r = sshbuf_get_u32(m, &authenticated)) != 0) 404 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 405 406 sshbuf_free(m); 407 408 debug3("%s: user %sauthenticated", 409 __func__, authenticated ? "" : "not "); 410 return (authenticated); 411 } 412 413 int 414 mm_user_key_allowed(struct ssh *ssh, struct passwd *pw, struct sshkey *key, 415 int pubkey_auth_attempt, struct sshauthopt **authoptp) 416 { 417 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key, 418 pubkey_auth_attempt, authoptp)); 419 } 420 421 int 422 mm_hostbased_key_allowed(struct passwd *pw, const char *user, const char *host, 423 struct sshkey *key) 424 { 425 return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0, NULL)); 426 } 427 428 int 429 mm_key_allowed(enum mm_keytype type, const char *user, const char *host, 430 struct sshkey *key, int pubkey_auth_attempt, struct sshauthopt **authoptp) 431 { 432 struct sshbuf *m; 433 int r, allowed = 0; 434 struct sshauthopt *opts = NULL; 435 436 debug3("%s entering", __func__); 437 438 if (authoptp != NULL) 439 *authoptp = NULL; 440 441 if ((m = sshbuf_new()) == NULL) 442 fatal("%s: sshbuf_new failed", __func__); 443 if ((r = sshbuf_put_u32(m, type)) != 0 || 444 (r = sshbuf_put_cstring(m, user ? user : "")) != 0 || 445 (r = sshbuf_put_cstring(m, host ? host : "")) != 0 || 446 (r = sshkey_puts(key, m)) != 0 || 447 (r = sshbuf_put_u32(m, pubkey_auth_attempt)) != 0) 448 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 449 450 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, m); 451 452 debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__); 453 mm_request_receive_expect(pmonitor->m_recvfd, 454 MONITOR_ANS_KEYALLOWED, m); 455 456 if ((r = sshbuf_get_u32(m, &allowed)) != 0) 457 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 458 if (allowed && type == MM_USERKEY) { 459 if ((r = sshauthopt_deserialise(m, &opts)) != 0) 460 fatal("%s: sshauthopt_deserialise: %s", 461 __func__, ssh_err(r)); 462 } 463 sshbuf_free(m); 464 465 if (authoptp != NULL) { 466 *authoptp = opts; 467 opts = NULL; 468 } 469 sshauthopt_free(opts); 470 471 return allowed; 472 } 473 474 /* 475 * This key verify needs to send the key type along, because the 476 * privileged parent makes the decision if the key is allowed 477 * for authentication. 478 */ 479 480 int 481 mm_sshkey_verify(const struct sshkey *key, const u_char *sig, size_t siglen, 482 const u_char *data, size_t datalen, const char *sigalg, u_int compat) 483 { 484 struct sshbuf *m; 485 u_int encoded_ret = 0; 486 int r; 487 488 debug3("%s entering", __func__); 489 490 491 if ((m = sshbuf_new()) == NULL) 492 fatal("%s: sshbuf_new failed", __func__); 493 if ((r = sshkey_puts(key, m)) != 0 || 494 (r = sshbuf_put_string(m, sig, siglen)) != 0 || 495 (r = sshbuf_put_string(m, data, datalen)) != 0 || 496 (r = sshbuf_put_cstring(m, sigalg == NULL ? "" : sigalg)) != 0) 497 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 498 499 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, m); 500 501 debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__); 502 mm_request_receive_expect(pmonitor->m_recvfd, 503 MONITOR_ANS_KEYVERIFY, m); 504 505 if ((r = sshbuf_get_u32(m, &encoded_ret)) != 0) 506 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 507 508 sshbuf_free(m); 509 510 if (encoded_ret != 0) 511 return SSH_ERR_SIGNATURE_INVALID; 512 return 0; 513 } 514 515 void 516 mm_send_keystate(struct monitor *monitor) 517 { 518 struct ssh *ssh = active_state; /* XXX */ 519 struct sshbuf *m; 520 int r; 521 522 if ((m = sshbuf_new()) == NULL) 523 fatal("%s: sshbuf_new failed", __func__); 524 if ((r = ssh_packet_get_state(ssh, m)) != 0) 525 fatal("%s: get_state failed: %s", 526 __func__, ssh_err(r)); 527 mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m); 528 debug3("%s: Finished sending state", __func__); 529 sshbuf_free(m); 530 } 531 532 int 533 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen) 534 { 535 struct sshbuf *m; 536 char *p, *msg; 537 int success = 0, tmp1 = -1, tmp2 = -1, r; 538 539 /* Kludge: ensure there are fds free to receive the pty/tty */ 540 if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 || 541 (tmp2 = dup(pmonitor->m_recvfd)) == -1) { 542 error("%s: cannot allocate fds for pty", __func__); 543 if (tmp1 > 0) 544 close(tmp1); 545 if (tmp2 > 0) 546 close(tmp2); 547 return 0; 548 } 549 close(tmp1); 550 close(tmp2); 551 552 if ((m = sshbuf_new()) == NULL) 553 fatal("%s: sshbuf_new failed", __func__); 554 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, m); 555 556 debug3("%s: waiting for MONITOR_ANS_PTY", __func__); 557 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, m); 558 559 if ((r = sshbuf_get_u32(m, &success)) != 0) 560 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 561 if (success == 0) { 562 debug3("%s: pty alloc failed", __func__); 563 sshbuf_free(m); 564 return (0); 565 } 566 if ((r = sshbuf_get_cstring(m, &p, NULL)) != 0 || 567 (r = sshbuf_get_cstring(m, &msg, NULL)) != 0) 568 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 569 sshbuf_free(m); 570 571 strlcpy(namebuf, p, namebuflen); /* Possible truncation */ 572 free(p); 573 574 if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0) 575 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 576 free(msg); 577 578 if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 || 579 (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1) 580 fatal("%s: receive fds failed", __func__); 581 582 /* Success */ 583 return (1); 584 } 585 586 void 587 mm_session_pty_cleanup2(Session *s) 588 { 589 struct sshbuf *m; 590 int r; 591 592 if (s->ttyfd == -1) 593 return; 594 if ((m = sshbuf_new()) == NULL) 595 fatal("%s: sshbuf_new failed", __func__); 596 if ((r = sshbuf_put_cstring(m, s->tty)) != 0) 597 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 598 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, m); 599 sshbuf_free(m); 600 601 /* closed dup'ed master */ 602 if (s->ptymaster != -1 && close(s->ptymaster) < 0) 603 error("close(s->ptymaster/%d): %s", 604 s->ptymaster, strerror(errno)); 605 606 /* unlink pty from session */ 607 s->ttyfd = -1; 608 } 609 610 /* Request process termination */ 611 612 void 613 mm_terminate(void) 614 { 615 struct sshbuf *m; 616 617 if ((m = sshbuf_new()) == NULL) 618 fatal("%s: sshbuf_new failed", __func__); 619 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, m); 620 sshbuf_free(m); 621 } 622 623 static void 624 mm_chall_setup(char **name, char **infotxt, u_int *numprompts, 625 char ***prompts, u_int **echo_on) 626 { 627 *name = xstrdup(""); 628 *infotxt = xstrdup(""); 629 *numprompts = 1; 630 *prompts = xcalloc(*numprompts, sizeof(char *)); 631 *echo_on = xcalloc(*numprompts, sizeof(u_int)); 632 (*echo_on)[0] = 0; 633 } 634 635 int 636 mm_bsdauth_query(void *ctx, char **name, char **infotxt, 637 u_int *numprompts, char ***prompts, u_int **echo_on) 638 { 639 struct sshbuf *m; 640 u_int success; 641 char *challenge; 642 int r; 643 644 debug3("%s: entering", __func__); 645 646 if ((m = sshbuf_new()) == NULL) 647 fatal("%s: sshbuf_new failed", __func__); 648 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, m); 649 650 mm_request_receive_expect(pmonitor->m_recvfd, 651 MONITOR_ANS_BSDAUTHQUERY, m); 652 if ((r = sshbuf_get_u32(m, &success)) != 0) 653 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 654 if (success == 0) { 655 debug3("%s: no challenge", __func__); 656 sshbuf_free(m); 657 return (-1); 658 } 659 660 /* Get the challenge, and format the response */ 661 if ((r = sshbuf_get_cstring(m, &challenge, NULL)) != 0) 662 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 663 sshbuf_free(m); 664 665 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 666 (*prompts)[0] = challenge; 667 668 debug3("%s: received challenge: %s", __func__, challenge); 669 670 return (0); 671 } 672 673 int 674 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses) 675 { 676 struct sshbuf *m; 677 int r, authok; 678 679 debug3("%s: entering", __func__); 680 if (numresponses != 1) 681 return (-1); 682 683 if ((m = sshbuf_new()) == NULL) 684 fatal("%s: sshbuf_new failed", __func__); 685 if ((r = sshbuf_put_cstring(m, responses[0])) != 0) 686 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 687 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, m); 688 689 mm_request_receive_expect(pmonitor->m_recvfd, 690 MONITOR_ANS_BSDAUTHRESPOND, m); 691 692 if ((r = sshbuf_get_u32(m, &authok)) != 0) 693 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 694 sshbuf_free(m); 695 696 return ((authok == 0) ? -1 : 0); 697 } 698 699 #ifdef GSSAPI 700 OM_uint32 701 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid) 702 { 703 struct sshbuf *m; 704 OM_uint32 major; 705 int r; 706 707 /* Client doesn't get to see the context */ 708 *ctx = NULL; 709 710 if ((m = sshbuf_new()) == NULL) 711 fatal("%s: sshbuf_new failed", __func__); 712 if ((r = sshbuf_put_string(m, goid->elements, goid->length)) != 0) 713 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 714 715 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, m); 716 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, m); 717 718 if ((r = sshbuf_get_u32(m, &major)) != 0) 719 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 720 721 sshbuf_free(m); 722 return (major); 723 } 724 725 OM_uint32 726 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in, 727 gss_buffer_desc *out, OM_uint32 *flagsp) 728 { 729 struct sshbuf *m; 730 OM_uint32 major; 731 u_int flags; 732 int r; 733 734 if ((m = sshbuf_new()) == NULL) 735 fatal("%s: sshbuf_new failed", __func__); 736 if ((r = sshbuf_put_string(m, in->value, in->length)) != 0) 737 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 738 739 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, m); 740 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, m); 741 742 if ((r = sshbuf_get_u32(m, &major)) != 0 || 743 (r = ssh_gssapi_get_buffer_desc(m, out)) != 0) 744 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 745 if (flagsp != NULL) { 746 if ((r = sshbuf_get_u32(m, &flags)) != 0) 747 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 748 *flagsp = flags; 749 } 750 751 sshbuf_free(m); 752 753 return (major); 754 } 755 756 OM_uint32 757 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic) 758 { 759 struct sshbuf *m; 760 OM_uint32 major; 761 int r; 762 763 if ((m = sshbuf_new()) == NULL) 764 fatal("%s: sshbuf_new failed", __func__); 765 if ((r = sshbuf_put_string(m, gssbuf->value, gssbuf->length)) != 0 || 766 (r = sshbuf_put_string(m, gssmic->value, gssmic->length)) != 0) 767 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 768 769 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, m); 770 mm_request_receive_expect(pmonitor->m_recvfd, 771 MONITOR_ANS_GSSCHECKMIC, m); 772 773 if ((r = sshbuf_get_u32(m, &major)) != 0) 774 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 775 sshbuf_free(m); 776 return(major); 777 } 778 779 int 780 mm_ssh_gssapi_userok(char *user) 781 { 782 struct sshbuf *m; 783 int r, authenticated = 0; 784 785 if ((m = sshbuf_new()) == NULL) 786 fatal("%s: sshbuf_new failed", __func__); 787 788 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, m); 789 mm_request_receive_expect(pmonitor->m_recvfd, 790 MONITOR_ANS_GSSUSEROK, m); 791 792 if ((r = sshbuf_get_u32(m, &authenticated)) != 0) 793 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 794 795 sshbuf_free(m); 796 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not "); 797 return (authenticated); 798 } 799 #endif /* GSSAPI */ 800