1 /* $OpenBSD: monitor_wrap.c,v 1.122 2020/11/27 00:37:10 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 <stdarg.h> 38 #include <unistd.h> 39 40 #ifdef WITH_OPENSSL 41 #include <openssl/bn.h> 42 #include <openssl/dh.h> 43 #endif 44 45 #include "xmalloc.h" 46 #include "ssh.h" 47 #ifdef WITH_OPENSSL 48 #include "dh.h" 49 #endif 50 #include "sshbuf.h" 51 #include "sshkey.h" 52 #include "cipher.h" 53 #include "kex.h" 54 #include "hostfile.h" 55 #include "auth.h" 56 #include "auth-options.h" 57 #include "packet.h" 58 #include "mac.h" 59 #include "log.h" 60 #include "monitor.h" 61 #ifdef GSSAPI 62 #include "ssh-gss.h" 63 #endif 64 #include "monitor_wrap.h" 65 #include "atomicio.h" 66 #include "monitor_fdpass.h" 67 #include "misc.h" 68 69 #include "channels.h" 70 #include "session.h" 71 #include "servconf.h" 72 73 #include "ssherr.h" 74 75 /* Imports */ 76 extern struct monitor *pmonitor; 77 extern struct sshbuf *loginmsg; 78 extern ServerOptions options; 79 80 void 81 mm_log_handler(const char *file, const char *func, int line, 82 LogLevel level, const char *msg, void *ctx) 83 { 84 struct sshbuf *log_msg; 85 struct monitor *mon = (struct monitor *)ctx; 86 int r; 87 size_t len; 88 89 if (mon->m_log_sendfd == -1) 90 fatal_f("no log channel"); 91 92 if ((log_msg = sshbuf_new()) == NULL) 93 fatal_f("sshbuf_new failed"); 94 95 if ((r = sshbuf_put_u32(log_msg, 0)) != 0 || /* length; filled below */ 96 (r = sshbuf_put_cstring(log_msg, file)) != 0 || 97 (r = sshbuf_put_cstring(log_msg, func)) != 0 || 98 (r = sshbuf_put_u32(log_msg, (u_int)line)) != 0 || 99 (r = sshbuf_put_u32(log_msg, level)) != 0 || 100 (r = sshbuf_put_cstring(log_msg, msg)) != 0) 101 fatal_fr(r, "assemble"); 102 if ((len = sshbuf_len(log_msg)) < 4 || len > 0xffffffff) 103 fatal_f("bad length %zu", len); 104 POKE_U32(sshbuf_mutable_ptr(log_msg), len - 4); 105 if (atomicio(vwrite, mon->m_log_sendfd, 106 sshbuf_mutable_ptr(log_msg), len) != len) 107 fatal_f("write: %s", strerror(errno)); 108 sshbuf_free(log_msg); 109 } 110 111 int 112 mm_is_monitor(void) 113 { 114 /* 115 * m_pid is only set in the privileged part, and 116 * points to the unprivileged child. 117 */ 118 return (pmonitor && pmonitor->m_pid > 0); 119 } 120 121 void 122 mm_request_send(int sock, enum monitor_reqtype type, struct sshbuf *m) 123 { 124 size_t mlen = sshbuf_len(m); 125 u_char buf[5]; 126 127 debug3_f("entering, type %d", type); 128 129 if (mlen >= 0xffffffff) 130 fatal_f("bad length %zu", mlen); 131 POKE_U32(buf, mlen + 1); 132 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */ 133 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf)) 134 fatal_f("write: %s", strerror(errno)); 135 if (atomicio(vwrite, sock, sshbuf_mutable_ptr(m), mlen) != mlen) 136 fatal_f("write: %s", strerror(errno)); 137 } 138 139 void 140 mm_request_receive(int sock, struct sshbuf *m) 141 { 142 u_char buf[4], *p = NULL; 143 u_int msg_len; 144 int r; 145 146 debug3_f("entering"); 147 148 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) { 149 if (errno == EPIPE) 150 cleanup_exit(255); 151 fatal_f("read: %s", strerror(errno)); 152 } 153 msg_len = PEEK_U32(buf); 154 if (msg_len > 256 * 1024) 155 fatal_f("read: bad msg_len %d", msg_len); 156 sshbuf_reset(m); 157 if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) 158 fatal_fr(r, "reserve"); 159 if (atomicio(read, sock, p, msg_len) != msg_len) 160 fatal_f("read: %s", strerror(errno)); 161 } 162 163 void 164 mm_request_receive_expect(int sock, enum monitor_reqtype type, struct sshbuf *m) 165 { 166 u_char rtype; 167 int r; 168 169 debug3_f("entering, type %d", type); 170 171 mm_request_receive(sock, m); 172 if ((r = sshbuf_get_u8(m, &rtype)) != 0) 173 fatal_fr(r, "parse"); 174 if (rtype != type) 175 fatal_f("read: rtype %d != type %d", rtype, type); 176 } 177 178 #ifdef WITH_OPENSSL 179 DH * 180 mm_choose_dh(int min, int nbits, int max) 181 { 182 BIGNUM *p, *g; 183 int r; 184 u_char success = 0; 185 struct sshbuf *m; 186 187 if ((m = sshbuf_new()) == NULL) 188 fatal_f("sshbuf_new failed"); 189 if ((r = sshbuf_put_u32(m, min)) != 0 || 190 (r = sshbuf_put_u32(m, nbits)) != 0 || 191 (r = sshbuf_put_u32(m, max)) != 0) 192 fatal_fr(r, "assemble"); 193 194 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, m); 195 196 debug3_f("waiting for MONITOR_ANS_MODULI"); 197 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, m); 198 199 if ((r = sshbuf_get_u8(m, &success)) != 0) 200 fatal_fr(r, "parse success"); 201 if (success == 0) 202 fatal_f("MONITOR_ANS_MODULI failed"); 203 204 if ((r = sshbuf_get_bignum2(m, &p)) != 0 || 205 (r = sshbuf_get_bignum2(m, &g)) != 0) 206 fatal_fr(r, "parse group"); 207 208 debug3_f("remaining %zu", 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 ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp, 217 const u_char *data, size_t datalen, const char *hostkey_alg, 218 const char *sk_provider, const char *sk_pin, u_int compat) 219 { 220 struct kex *kex = *pmonitor->m_pkex; 221 struct sshbuf *m; 222 u_int ndx = kex->host_key_index(key, 0, ssh); 223 int r; 224 225 debug3_f("entering"); 226 if ((m = sshbuf_new()) == NULL) 227 fatal_f("sshbuf_new failed"); 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_fr(r, "assemble"); 233 234 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, m); 235 236 debug3_f("waiting for MONITOR_ANS_SIGN"); 237 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, m); 238 if ((r = sshbuf_get_string(m, sigp, lenp)) != 0) 239 fatal_fr(r, "parse"); 240 sshbuf_free(m); 241 242 return (0); 243 } 244 245 #define GETPW(b, id) \ 246 do { \ 247 if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0) \ 248 fatal_fr(r, "parse pw %s", #id); \ 249 if (len != sizeof(pw->id)) \ 250 fatal_fr(r, "bad length for %s", #id); \ 251 memcpy(&pw->id, p, len); \ 252 } while (0) 253 254 struct passwd * 255 mm_getpwnamallow(struct ssh *ssh, const char *username) 256 { 257 struct sshbuf *m; 258 struct passwd *pw; 259 size_t len; 260 u_int i; 261 ServerOptions *newopts; 262 int r; 263 u_char ok; 264 const u_char *p; 265 266 debug3_f("entering"); 267 268 if ((m = sshbuf_new()) == NULL) 269 fatal_f("sshbuf_new failed"); 270 if ((r = sshbuf_put_cstring(m, username)) != 0) 271 fatal_fr(r, "assemble"); 272 273 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, m); 274 275 debug3_f("waiting for MONITOR_ANS_PWNAM"); 276 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, m); 277 278 if ((r = sshbuf_get_u8(m, &ok)) != 0) 279 fatal_fr(r, "parse success"); 280 if (ok == 0) { 281 pw = NULL; 282 goto out; 283 } 284 285 pw = xcalloc(sizeof(*pw), 1); 286 GETPW(m, pw_uid); 287 GETPW(m, pw_gid); 288 GETPW(m, pw_change); 289 GETPW(m, pw_expire); 290 if ((r = sshbuf_get_cstring(m, &pw->pw_name, NULL)) != 0 || 291 (r = sshbuf_get_cstring(m, &pw->pw_passwd, NULL)) != 0 || 292 (r = sshbuf_get_cstring(m, &pw->pw_gecos, NULL)) != 0 || 293 (r = sshbuf_get_cstring(m, &pw->pw_class, NULL)) != 0 || 294 (r = sshbuf_get_cstring(m, &pw->pw_dir, NULL)) != 0 || 295 (r = sshbuf_get_cstring(m, &pw->pw_shell, NULL)) != 0) 296 fatal_fr(r, "parse pw"); 297 298 out: 299 /* copy options block as a Match directive may have changed some */ 300 if ((r = sshbuf_get_string_direct(m, &p, &len)) != 0) 301 fatal_fr(r, "parse opts"); 302 if (len != sizeof(*newopts)) 303 fatal_f("option block size mismatch"); 304 newopts = xcalloc(sizeof(*newopts), 1); 305 memcpy(newopts, p, sizeof(*newopts)); 306 307 #define M_CP_STROPT(x) do { \ 308 if (newopts->x != NULL && \ 309 (r = sshbuf_get_cstring(m, &newopts->x, NULL)) != 0) \ 310 fatal_fr(r, "parse %s", #x); \ 311 } while (0) 312 #define M_CP_STRARRAYOPT(x, nx) do { \ 313 newopts->x = newopts->nx == 0 ? \ 314 NULL : xcalloc(newopts->nx, sizeof(*newopts->x)); \ 315 for (i = 0; i < newopts->nx; i++) { \ 316 if ((r = sshbuf_get_cstring(m, \ 317 &newopts->x[i], NULL)) != 0) \ 318 fatal_fr(r, "parse %s", #x); \ 319 } \ 320 } while (0) 321 /* See comment in servconf.h */ 322 COPY_MATCH_STRING_OPTS(); 323 #undef M_CP_STROPT 324 #undef M_CP_STRARRAYOPT 325 326 copy_set_server_options(&options, newopts, 1); 327 log_change_level(options.log_level); 328 log_verbose_reset(); 329 for (i = 0; i < options.num_log_verbose; i++) 330 log_verbose_add(options.log_verbose[i]); 331 process_permitopen(ssh, &options); 332 free(newopts); 333 334 sshbuf_free(m); 335 336 return (pw); 337 } 338 339 char * 340 mm_auth2_read_banner(void) 341 { 342 struct sshbuf *m; 343 char *banner; 344 int r; 345 346 debug3_f("entering"); 347 348 if ((m = sshbuf_new()) == NULL) 349 fatal_f("sshbuf_new failed"); 350 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, m); 351 sshbuf_reset(m); 352 353 mm_request_receive_expect(pmonitor->m_recvfd, 354 MONITOR_ANS_AUTH2_READ_BANNER, m); 355 if ((r = sshbuf_get_cstring(m, &banner, NULL)) != 0) 356 fatal_fr(r, "parse"); 357 sshbuf_free(m); 358 359 /* treat empty banner as missing banner */ 360 if (strlen(banner) == 0) { 361 free(banner); 362 banner = NULL; 363 } 364 return (banner); 365 } 366 367 /* Inform the privileged process about service and style */ 368 369 void 370 mm_inform_authserv(char *service, char *style) 371 { 372 struct sshbuf *m; 373 int r; 374 375 debug3_f("entering"); 376 377 if ((m = sshbuf_new()) == NULL) 378 fatal_f("sshbuf_new failed"); 379 if ((r = sshbuf_put_cstring(m, service)) != 0 || 380 (r = sshbuf_put_cstring(m, style ? style : "")) != 0) 381 fatal_fr(r, "assemble"); 382 383 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, m); 384 385 sshbuf_free(m); 386 } 387 388 /* Do the password authentication */ 389 int 390 mm_auth_password(struct ssh *ssh, char *password) 391 { 392 struct sshbuf *m; 393 int r, authenticated = 0; 394 395 debug3_f("entering"); 396 397 if ((m = sshbuf_new()) == NULL) 398 fatal_f("sshbuf_new failed"); 399 if ((r = sshbuf_put_cstring(m, password)) != 0) 400 fatal_fr(r, "assemble"); 401 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, m); 402 403 debug3_f("waiting for MONITOR_ANS_AUTHPASSWORD"); 404 mm_request_receive_expect(pmonitor->m_recvfd, 405 MONITOR_ANS_AUTHPASSWORD, m); 406 407 if ((r = sshbuf_get_u32(m, &authenticated)) != 0) 408 fatal_fr(r, "parse"); 409 410 sshbuf_free(m); 411 412 debug3_f("user %sauthenticated", authenticated ? "" : "not "); 413 return (authenticated); 414 } 415 416 int 417 mm_user_key_allowed(struct ssh *ssh, struct passwd *pw, struct sshkey *key, 418 int pubkey_auth_attempt, struct sshauthopt **authoptp) 419 { 420 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key, 421 pubkey_auth_attempt, authoptp)); 422 } 423 424 int 425 mm_hostbased_key_allowed(struct ssh *ssh, struct passwd *pw, 426 const char *user, const char *host, struct sshkey *key) 427 { 428 return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0, NULL)); 429 } 430 431 int 432 mm_key_allowed(enum mm_keytype type, const char *user, const char *host, 433 struct sshkey *key, int pubkey_auth_attempt, struct sshauthopt **authoptp) 434 { 435 struct sshbuf *m; 436 int r, allowed = 0; 437 struct sshauthopt *opts = NULL; 438 439 debug3_f("entering"); 440 441 if (authoptp != NULL) 442 *authoptp = NULL; 443 444 if ((m = sshbuf_new()) == NULL) 445 fatal_f("sshbuf_new failed"); 446 if ((r = sshbuf_put_u32(m, type)) != 0 || 447 (r = sshbuf_put_cstring(m, user ? user : "")) != 0 || 448 (r = sshbuf_put_cstring(m, host ? host : "")) != 0 || 449 (r = sshkey_puts(key, m)) != 0 || 450 (r = sshbuf_put_u32(m, pubkey_auth_attempt)) != 0) 451 fatal_fr(r, "assemble"); 452 453 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, m); 454 455 debug3_f("waiting for MONITOR_ANS_KEYALLOWED"); 456 mm_request_receive_expect(pmonitor->m_recvfd, 457 MONITOR_ANS_KEYALLOWED, m); 458 459 if ((r = sshbuf_get_u32(m, &allowed)) != 0) 460 fatal_fr(r, "parse"); 461 if (allowed && type == MM_USERKEY && 462 (r = sshauthopt_deserialise(m, &opts)) != 0) 463 fatal_fr(r, "sshauthopt_deserialise"); 464 sshbuf_free(m); 465 466 if (authoptp != NULL) { 467 *authoptp = opts; 468 opts = NULL; 469 } 470 sshauthopt_free(opts); 471 472 return allowed; 473 } 474 475 /* 476 * This key verify needs to send the key type along, because the 477 * privileged parent makes the decision if the key is allowed 478 * for authentication. 479 */ 480 481 int 482 mm_sshkey_verify(const struct sshkey *key, const u_char *sig, size_t siglen, 483 const u_char *data, size_t datalen, const char *sigalg, u_int compat, 484 struct sshkey_sig_details **sig_detailsp) 485 { 486 struct sshbuf *m; 487 u_int encoded_ret = 0; 488 int r; 489 u_char sig_details_present, flags; 490 u_int counter; 491 492 debug3_f("entering"); 493 494 if (sig_detailsp != NULL) 495 *sig_detailsp = NULL; 496 if ((m = sshbuf_new()) == NULL) 497 fatal_f("sshbuf_new failed"); 498 if ((r = sshkey_puts(key, m)) != 0 || 499 (r = sshbuf_put_string(m, sig, siglen)) != 0 || 500 (r = sshbuf_put_string(m, data, datalen)) != 0 || 501 (r = sshbuf_put_cstring(m, sigalg == NULL ? "" : sigalg)) != 0) 502 fatal_fr(r, "assemble"); 503 504 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, m); 505 506 debug3_f("waiting for MONITOR_ANS_KEYVERIFY"); 507 mm_request_receive_expect(pmonitor->m_recvfd, 508 MONITOR_ANS_KEYVERIFY, m); 509 510 if ((r = sshbuf_get_u32(m, &encoded_ret)) != 0 || 511 (r = sshbuf_get_u8(m, &sig_details_present)) != 0) 512 fatal_fr(r, "parse"); 513 if (sig_details_present && encoded_ret == 0) { 514 if ((r = sshbuf_get_u32(m, &counter)) != 0 || 515 (r = sshbuf_get_u8(m, &flags)) != 0) 516 fatal_fr(r, "parse sig_details"); 517 if (sig_detailsp != NULL) { 518 *sig_detailsp = xcalloc(1, sizeof(**sig_detailsp)); 519 (*sig_detailsp)->sk_counter = counter; 520 (*sig_detailsp)->sk_flags = flags; 521 } 522 } 523 524 sshbuf_free(m); 525 526 if (encoded_ret != 0) 527 return SSH_ERR_SIGNATURE_INVALID; 528 return 0; 529 } 530 531 void 532 mm_send_keystate(struct ssh *ssh, struct monitor *monitor) 533 { 534 struct sshbuf *m; 535 int r; 536 537 if ((m = sshbuf_new()) == NULL) 538 fatal_f("sshbuf_new failed"); 539 if ((r = ssh_packet_get_state(ssh, m)) != 0) 540 fatal_fr(r, "ssh_packet_get_state"); 541 mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m); 542 debug3_f("Finished sending state"); 543 sshbuf_free(m); 544 } 545 546 int 547 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen) 548 { 549 struct sshbuf *m; 550 char *p, *msg; 551 int success = 0, tmp1 = -1, tmp2 = -1, r; 552 553 /* Kludge: ensure there are fds free to receive the pty/tty */ 554 if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 || 555 (tmp2 = dup(pmonitor->m_recvfd)) == -1) { 556 error_f("cannot allocate fds for pty"); 557 if (tmp1 > 0) 558 close(tmp1); 559 if (tmp2 > 0) 560 close(tmp2); 561 return 0; 562 } 563 close(tmp1); 564 close(tmp2); 565 566 if ((m = sshbuf_new()) == NULL) 567 fatal_f("sshbuf_new failed"); 568 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, m); 569 570 debug3_f("waiting for MONITOR_ANS_PTY"); 571 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, m); 572 573 if ((r = sshbuf_get_u32(m, &success)) != 0) 574 fatal_fr(r, "parse success"); 575 if (success == 0) { 576 debug3_f("pty alloc failed"); 577 sshbuf_free(m); 578 return (0); 579 } 580 if ((r = sshbuf_get_cstring(m, &p, NULL)) != 0 || 581 (r = sshbuf_get_cstring(m, &msg, NULL)) != 0) 582 fatal_fr(r, "parse"); 583 sshbuf_free(m); 584 585 strlcpy(namebuf, p, namebuflen); /* Possible truncation */ 586 free(p); 587 588 if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0) 589 fatal_fr(r, "put loginmsg"); 590 free(msg); 591 592 if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 || 593 (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1) 594 fatal_f("receive fds failed"); 595 596 /* Success */ 597 return (1); 598 } 599 600 void 601 mm_session_pty_cleanup2(Session *s) 602 { 603 struct sshbuf *m; 604 int r; 605 606 if (s->ttyfd == -1) 607 return; 608 if ((m = sshbuf_new()) == NULL) 609 fatal_f("sshbuf_new failed"); 610 if ((r = sshbuf_put_cstring(m, s->tty)) != 0) 611 fatal_fr(r, "assmble"); 612 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, m); 613 sshbuf_free(m); 614 615 /* closed dup'ed master */ 616 if (s->ptymaster != -1 && close(s->ptymaster) == -1) 617 error("close(s->ptymaster/%d): %s", 618 s->ptymaster, strerror(errno)); 619 620 /* unlink pty from session */ 621 s->ttyfd = -1; 622 } 623 624 /* Request process termination */ 625 626 void 627 mm_terminate(void) 628 { 629 struct sshbuf *m; 630 631 if ((m = sshbuf_new()) == NULL) 632 fatal_f("sshbuf_new failed"); 633 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, m); 634 sshbuf_free(m); 635 } 636 637 static void 638 mm_chall_setup(char **name, char **infotxt, u_int *numprompts, 639 char ***prompts, u_int **echo_on) 640 { 641 *name = xstrdup(""); 642 *infotxt = xstrdup(""); 643 *numprompts = 1; 644 *prompts = xcalloc(*numprompts, sizeof(char *)); 645 *echo_on = xcalloc(*numprompts, sizeof(u_int)); 646 (*echo_on)[0] = 0; 647 } 648 649 int 650 mm_bsdauth_query(void *ctx, char **name, char **infotxt, 651 u_int *numprompts, char ***prompts, u_int **echo_on) 652 { 653 struct sshbuf *m; 654 u_int success; 655 char *challenge; 656 int r; 657 658 debug3_f("entering"); 659 660 if ((m = sshbuf_new()) == NULL) 661 fatal_f("sshbuf_new failed"); 662 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, m); 663 664 mm_request_receive_expect(pmonitor->m_recvfd, 665 MONITOR_ANS_BSDAUTHQUERY, m); 666 if ((r = sshbuf_get_u32(m, &success)) != 0) 667 fatal_fr(r, "parse success"); 668 if (success == 0) { 669 debug3_f("no challenge"); 670 sshbuf_free(m); 671 return (-1); 672 } 673 674 /* Get the challenge, and format the response */ 675 if ((r = sshbuf_get_cstring(m, &challenge, NULL)) != 0) 676 fatal_fr(r, "parse challenge"); 677 sshbuf_free(m); 678 679 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 680 (*prompts)[0] = challenge; 681 682 debug3_f("received challenge: %s", challenge); 683 684 return (0); 685 } 686 687 int 688 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses) 689 { 690 struct sshbuf *m; 691 int r, authok; 692 693 debug3_f("entering"); 694 if (numresponses != 1) 695 return (-1); 696 697 if ((m = sshbuf_new()) == NULL) 698 fatal_f("sshbuf_new failed"); 699 if ((r = sshbuf_put_cstring(m, responses[0])) != 0) 700 fatal_fr(r, "assemble"); 701 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, m); 702 703 mm_request_receive_expect(pmonitor->m_recvfd, 704 MONITOR_ANS_BSDAUTHRESPOND, m); 705 706 if ((r = sshbuf_get_u32(m, &authok)) != 0) 707 fatal_fr(r, "parse"); 708 sshbuf_free(m); 709 710 return ((authok == 0) ? -1 : 0); 711 } 712 713 #ifdef GSSAPI 714 OM_uint32 715 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid) 716 { 717 struct sshbuf *m; 718 OM_uint32 major; 719 int r; 720 721 /* Client doesn't get to see the context */ 722 *ctx = NULL; 723 724 if ((m = sshbuf_new()) == NULL) 725 fatal_f("sshbuf_new failed"); 726 if ((r = sshbuf_put_string(m, goid->elements, goid->length)) != 0) 727 fatal_fr(r, "assemble"); 728 729 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, m); 730 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, m); 731 732 if ((r = sshbuf_get_u32(m, &major)) != 0) 733 fatal_fr(r, "parse"); 734 735 sshbuf_free(m); 736 return (major); 737 } 738 739 OM_uint32 740 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in, 741 gss_buffer_desc *out, OM_uint32 *flagsp) 742 { 743 struct sshbuf *m; 744 OM_uint32 major; 745 u_int flags; 746 int r; 747 748 if ((m = sshbuf_new()) == NULL) 749 fatal_f("sshbuf_new failed"); 750 if ((r = sshbuf_put_string(m, in->value, in->length)) != 0) 751 fatal_fr(r, "assemble"); 752 753 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, m); 754 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, m); 755 756 if ((r = sshbuf_get_u32(m, &major)) != 0 || 757 (r = ssh_gssapi_get_buffer_desc(m, out)) != 0) 758 fatal_fr(r, "parse"); 759 if (flagsp != NULL) { 760 if ((r = sshbuf_get_u32(m, &flags)) != 0) 761 fatal_fr(r, "parse flags"); 762 *flagsp = flags; 763 } 764 765 sshbuf_free(m); 766 767 return (major); 768 } 769 770 OM_uint32 771 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic) 772 { 773 struct sshbuf *m; 774 OM_uint32 major; 775 int r; 776 777 if ((m = sshbuf_new()) == NULL) 778 fatal_f("sshbuf_new failed"); 779 if ((r = sshbuf_put_string(m, gssbuf->value, gssbuf->length)) != 0 || 780 (r = sshbuf_put_string(m, gssmic->value, gssmic->length)) != 0) 781 fatal_fr(r, "assemble"); 782 783 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, m); 784 mm_request_receive_expect(pmonitor->m_recvfd, 785 MONITOR_ANS_GSSCHECKMIC, m); 786 787 if ((r = sshbuf_get_u32(m, &major)) != 0) 788 fatal_fr(r, "parse"); 789 sshbuf_free(m); 790 return(major); 791 } 792 793 int 794 mm_ssh_gssapi_userok(char *user) 795 { 796 struct sshbuf *m; 797 int r, authenticated = 0; 798 799 if ((m = sshbuf_new()) == NULL) 800 fatal_f("sshbuf_new failed"); 801 802 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, m); 803 mm_request_receive_expect(pmonitor->m_recvfd, 804 MONITOR_ANS_GSSUSEROK, m); 805 806 if ((r = sshbuf_get_u32(m, &authenticated)) != 0) 807 fatal_fr(r, "parse"); 808 809 sshbuf_free(m); 810 debug3_f("user %sauthenticated", authenticated ? "" : "not "); 811 return (authenticated); 812 } 813 #endif /* GSSAPI */ 814