1 /* $OpenBSD: monitor_wrap.c,v 1.123 2021/04/15 16:24:31 markus 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(LogLevel level, int forced, const char *msg, void *ctx) 82 { 83 struct sshbuf *log_msg; 84 struct monitor *mon = (struct monitor *)ctx; 85 int r; 86 size_t len; 87 88 if (mon->m_log_sendfd == -1) 89 fatal_f("no log channel"); 90 91 if ((log_msg = sshbuf_new()) == NULL) 92 fatal_f("sshbuf_new failed"); 93 94 if ((r = sshbuf_put_u32(log_msg, 0)) != 0 || /* length; filled below */ 95 (r = sshbuf_put_u32(log_msg, level)) != 0 || 96 (r = sshbuf_put_u32(log_msg, forced)) != 0 || 97 (r = sshbuf_put_cstring(log_msg, msg)) != 0) 98 fatal_fr(r, "assemble"); 99 if ((len = sshbuf_len(log_msg)) < 4 || len > 0xffffffff) 100 fatal_f("bad length %zu", len); 101 POKE_U32(sshbuf_mutable_ptr(log_msg), len - 4); 102 if (atomicio(vwrite, mon->m_log_sendfd, 103 sshbuf_mutable_ptr(log_msg), len) != len) 104 fatal_f("write: %s", strerror(errno)); 105 sshbuf_free(log_msg); 106 } 107 108 int 109 mm_is_monitor(void) 110 { 111 /* 112 * m_pid is only set in the privileged part, and 113 * points to the unprivileged child. 114 */ 115 return (pmonitor && pmonitor->m_pid > 0); 116 } 117 118 void 119 mm_request_send(int sock, enum monitor_reqtype type, struct sshbuf *m) 120 { 121 size_t mlen = sshbuf_len(m); 122 u_char buf[5]; 123 124 debug3_f("entering, type %d", type); 125 126 if (mlen >= 0xffffffff) 127 fatal_f("bad length %zu", mlen); 128 POKE_U32(buf, mlen + 1); 129 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */ 130 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf)) 131 fatal_f("write: %s", strerror(errno)); 132 if (atomicio(vwrite, sock, sshbuf_mutable_ptr(m), mlen) != mlen) 133 fatal_f("write: %s", strerror(errno)); 134 } 135 136 void 137 mm_request_receive(int sock, struct sshbuf *m) 138 { 139 u_char buf[4], *p = NULL; 140 u_int msg_len; 141 int r; 142 143 debug3_f("entering"); 144 145 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) { 146 if (errno == EPIPE) 147 cleanup_exit(255); 148 fatal_f("read: %s", strerror(errno)); 149 } 150 msg_len = PEEK_U32(buf); 151 if (msg_len > 256 * 1024) 152 fatal_f("read: bad msg_len %d", msg_len); 153 sshbuf_reset(m); 154 if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) 155 fatal_fr(r, "reserve"); 156 if (atomicio(read, sock, p, msg_len) != msg_len) 157 fatal_f("read: %s", strerror(errno)); 158 } 159 160 void 161 mm_request_receive_expect(int sock, enum monitor_reqtype type, struct sshbuf *m) 162 { 163 u_char rtype; 164 int r; 165 166 debug3_f("entering, type %d", type); 167 168 mm_request_receive(sock, m); 169 if ((r = sshbuf_get_u8(m, &rtype)) != 0) 170 fatal_fr(r, "parse"); 171 if (rtype != type) 172 fatal_f("read: rtype %d != type %d", rtype, type); 173 } 174 175 #ifdef WITH_OPENSSL 176 DH * 177 mm_choose_dh(int min, int nbits, int max) 178 { 179 BIGNUM *p, *g; 180 int r; 181 u_char success = 0; 182 struct sshbuf *m; 183 184 if ((m = sshbuf_new()) == NULL) 185 fatal_f("sshbuf_new failed"); 186 if ((r = sshbuf_put_u32(m, min)) != 0 || 187 (r = sshbuf_put_u32(m, nbits)) != 0 || 188 (r = sshbuf_put_u32(m, max)) != 0) 189 fatal_fr(r, "assemble"); 190 191 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, m); 192 193 debug3_f("waiting for MONITOR_ANS_MODULI"); 194 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, m); 195 196 if ((r = sshbuf_get_u8(m, &success)) != 0) 197 fatal_fr(r, "parse success"); 198 if (success == 0) 199 fatal_f("MONITOR_ANS_MODULI failed"); 200 201 if ((r = sshbuf_get_bignum2(m, &p)) != 0 || 202 (r = sshbuf_get_bignum2(m, &g)) != 0) 203 fatal_fr(r, "parse group"); 204 205 debug3_f("remaining %zu", sshbuf_len(m)); 206 sshbuf_free(m); 207 208 return (dh_new_group(g, p)); 209 } 210 #endif 211 212 int 213 mm_sshkey_sign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp, 214 const u_char *data, size_t datalen, const char *hostkey_alg, 215 const char *sk_provider, const char *sk_pin, u_int compat) 216 { 217 struct kex *kex = *pmonitor->m_pkex; 218 struct sshbuf *m; 219 u_int ndx = kex->host_key_index(key, 0, ssh); 220 int r; 221 222 debug3_f("entering"); 223 if ((m = sshbuf_new()) == NULL) 224 fatal_f("sshbuf_new failed"); 225 if ((r = sshbuf_put_u32(m, ndx)) != 0 || 226 (r = sshbuf_put_string(m, data, datalen)) != 0 || 227 (r = sshbuf_put_cstring(m, hostkey_alg)) != 0 || 228 (r = sshbuf_put_u32(m, compat)) != 0) 229 fatal_fr(r, "assemble"); 230 231 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, m); 232 233 debug3_f("waiting for MONITOR_ANS_SIGN"); 234 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, m); 235 if ((r = sshbuf_get_string(m, sigp, lenp)) != 0) 236 fatal_fr(r, "parse"); 237 sshbuf_free(m); 238 239 return (0); 240 } 241 242 #define GETPW(b, id) \ 243 do { \ 244 if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0) \ 245 fatal_fr(r, "parse pw %s", #id); \ 246 if (len != sizeof(pw->id)) \ 247 fatal_fr(r, "bad length for %s", #id); \ 248 memcpy(&pw->id, p, len); \ 249 } while (0) 250 251 struct passwd * 252 mm_getpwnamallow(struct ssh *ssh, const char *username) 253 { 254 struct sshbuf *m; 255 struct passwd *pw; 256 size_t len; 257 u_int i; 258 ServerOptions *newopts; 259 int r; 260 u_char ok; 261 const u_char *p; 262 263 debug3_f("entering"); 264 265 if ((m = sshbuf_new()) == NULL) 266 fatal_f("sshbuf_new failed"); 267 if ((r = sshbuf_put_cstring(m, username)) != 0) 268 fatal_fr(r, "assemble"); 269 270 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, m); 271 272 debug3_f("waiting for MONITOR_ANS_PWNAM"); 273 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, m); 274 275 if ((r = sshbuf_get_u8(m, &ok)) != 0) 276 fatal_fr(r, "parse success"); 277 if (ok == 0) { 278 pw = NULL; 279 goto out; 280 } 281 282 pw = xcalloc(sizeof(*pw), 1); 283 GETPW(m, pw_uid); 284 GETPW(m, pw_gid); 285 GETPW(m, pw_change); 286 GETPW(m, pw_expire); 287 if ((r = sshbuf_get_cstring(m, &pw->pw_name, NULL)) != 0 || 288 (r = sshbuf_get_cstring(m, &pw->pw_passwd, NULL)) != 0 || 289 (r = sshbuf_get_cstring(m, &pw->pw_gecos, NULL)) != 0 || 290 (r = sshbuf_get_cstring(m, &pw->pw_class, NULL)) != 0 || 291 (r = sshbuf_get_cstring(m, &pw->pw_dir, NULL)) != 0 || 292 (r = sshbuf_get_cstring(m, &pw->pw_shell, NULL)) != 0) 293 fatal_fr(r, "parse pw"); 294 295 out: 296 /* copy options block as a Match directive may have changed some */ 297 if ((r = sshbuf_get_string_direct(m, &p, &len)) != 0) 298 fatal_fr(r, "parse opts"); 299 if (len != sizeof(*newopts)) 300 fatal_f("option block size mismatch"); 301 newopts = xcalloc(sizeof(*newopts), 1); 302 memcpy(newopts, p, sizeof(*newopts)); 303 304 #define M_CP_STROPT(x) do { \ 305 if (newopts->x != NULL && \ 306 (r = sshbuf_get_cstring(m, &newopts->x, NULL)) != 0) \ 307 fatal_fr(r, "parse %s", #x); \ 308 } while (0) 309 #define M_CP_STRARRAYOPT(x, nx) do { \ 310 newopts->x = newopts->nx == 0 ? \ 311 NULL : xcalloc(newopts->nx, sizeof(*newopts->x)); \ 312 for (i = 0; i < newopts->nx; i++) { \ 313 if ((r = sshbuf_get_cstring(m, \ 314 &newopts->x[i], NULL)) != 0) \ 315 fatal_fr(r, "parse %s", #x); \ 316 } \ 317 } while (0) 318 /* See comment in servconf.h */ 319 COPY_MATCH_STRING_OPTS(); 320 #undef M_CP_STROPT 321 #undef M_CP_STRARRAYOPT 322 323 copy_set_server_options(&options, newopts, 1); 324 log_change_level(options.log_level); 325 log_verbose_reset(); 326 for (i = 0; i < options.num_log_verbose; i++) 327 log_verbose_add(options.log_verbose[i]); 328 process_permitopen(ssh, &options); 329 free(newopts); 330 331 sshbuf_free(m); 332 333 return (pw); 334 } 335 336 char * 337 mm_auth2_read_banner(void) 338 { 339 struct sshbuf *m; 340 char *banner; 341 int r; 342 343 debug3_f("entering"); 344 345 if ((m = sshbuf_new()) == NULL) 346 fatal_f("sshbuf_new failed"); 347 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, m); 348 sshbuf_reset(m); 349 350 mm_request_receive_expect(pmonitor->m_recvfd, 351 MONITOR_ANS_AUTH2_READ_BANNER, m); 352 if ((r = sshbuf_get_cstring(m, &banner, NULL)) != 0) 353 fatal_fr(r, "parse"); 354 sshbuf_free(m); 355 356 /* treat empty banner as missing banner */ 357 if (strlen(banner) == 0) { 358 free(banner); 359 banner = NULL; 360 } 361 return (banner); 362 } 363 364 /* Inform the privileged process about service and style */ 365 366 void 367 mm_inform_authserv(char *service, char *style) 368 { 369 struct sshbuf *m; 370 int r; 371 372 debug3_f("entering"); 373 374 if ((m = sshbuf_new()) == NULL) 375 fatal_f("sshbuf_new failed"); 376 if ((r = sshbuf_put_cstring(m, service)) != 0 || 377 (r = sshbuf_put_cstring(m, style ? style : "")) != 0) 378 fatal_fr(r, "assemble"); 379 380 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, m); 381 382 sshbuf_free(m); 383 } 384 385 /* Do the password authentication */ 386 int 387 mm_auth_password(struct ssh *ssh, char *password) 388 { 389 struct sshbuf *m; 390 int r, authenticated = 0; 391 392 debug3_f("entering"); 393 394 if ((m = sshbuf_new()) == NULL) 395 fatal_f("sshbuf_new failed"); 396 if ((r = sshbuf_put_cstring(m, password)) != 0) 397 fatal_fr(r, "assemble"); 398 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, m); 399 400 debug3_f("waiting for MONITOR_ANS_AUTHPASSWORD"); 401 mm_request_receive_expect(pmonitor->m_recvfd, 402 MONITOR_ANS_AUTHPASSWORD, m); 403 404 if ((r = sshbuf_get_u32(m, &authenticated)) != 0) 405 fatal_fr(r, "parse"); 406 407 sshbuf_free(m); 408 409 debug3_f("user %sauthenticated", 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 ssh *ssh, struct passwd *pw, 423 const char *user, const char *host, 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_f("entering"); 437 438 if (authoptp != NULL) 439 *authoptp = NULL; 440 441 if ((m = sshbuf_new()) == NULL) 442 fatal_f("sshbuf_new failed"); 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_fr(r, "assemble"); 449 450 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, m); 451 452 debug3_f("waiting for MONITOR_ANS_KEYALLOWED"); 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_fr(r, "parse"); 458 if (allowed && type == MM_USERKEY && 459 (r = sshauthopt_deserialise(m, &opts)) != 0) 460 fatal_fr(r, "sshauthopt_deserialise"); 461 sshbuf_free(m); 462 463 if (authoptp != NULL) { 464 *authoptp = opts; 465 opts = NULL; 466 } 467 sshauthopt_free(opts); 468 469 return allowed; 470 } 471 472 /* 473 * This key verify needs to send the key type along, because the 474 * privileged parent makes the decision if the key is allowed 475 * for authentication. 476 */ 477 478 int 479 mm_sshkey_verify(const struct sshkey *key, const u_char *sig, size_t siglen, 480 const u_char *data, size_t datalen, const char *sigalg, u_int compat, 481 struct sshkey_sig_details **sig_detailsp) 482 { 483 struct sshbuf *m; 484 u_int encoded_ret = 0; 485 int r; 486 u_char sig_details_present, flags; 487 u_int counter; 488 489 debug3_f("entering"); 490 491 if (sig_detailsp != NULL) 492 *sig_detailsp = NULL; 493 if ((m = sshbuf_new()) == NULL) 494 fatal_f("sshbuf_new failed"); 495 if ((r = sshkey_puts(key, m)) != 0 || 496 (r = sshbuf_put_string(m, sig, siglen)) != 0 || 497 (r = sshbuf_put_string(m, data, datalen)) != 0 || 498 (r = sshbuf_put_cstring(m, sigalg == NULL ? "" : sigalg)) != 0) 499 fatal_fr(r, "assemble"); 500 501 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, m); 502 503 debug3_f("waiting for MONITOR_ANS_KEYVERIFY"); 504 mm_request_receive_expect(pmonitor->m_recvfd, 505 MONITOR_ANS_KEYVERIFY, m); 506 507 if ((r = sshbuf_get_u32(m, &encoded_ret)) != 0 || 508 (r = sshbuf_get_u8(m, &sig_details_present)) != 0) 509 fatal_fr(r, "parse"); 510 if (sig_details_present && encoded_ret == 0) { 511 if ((r = sshbuf_get_u32(m, &counter)) != 0 || 512 (r = sshbuf_get_u8(m, &flags)) != 0) 513 fatal_fr(r, "parse sig_details"); 514 if (sig_detailsp != NULL) { 515 *sig_detailsp = xcalloc(1, sizeof(**sig_detailsp)); 516 (*sig_detailsp)->sk_counter = counter; 517 (*sig_detailsp)->sk_flags = flags; 518 } 519 } 520 521 sshbuf_free(m); 522 523 if (encoded_ret != 0) 524 return SSH_ERR_SIGNATURE_INVALID; 525 return 0; 526 } 527 528 void 529 mm_send_keystate(struct ssh *ssh, struct monitor *monitor) 530 { 531 struct sshbuf *m; 532 int r; 533 534 if ((m = sshbuf_new()) == NULL) 535 fatal_f("sshbuf_new failed"); 536 if ((r = ssh_packet_get_state(ssh, m)) != 0) 537 fatal_fr(r, "ssh_packet_get_state"); 538 mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m); 539 debug3_f("Finished sending state"); 540 sshbuf_free(m); 541 } 542 543 int 544 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen) 545 { 546 struct sshbuf *m; 547 char *p, *msg; 548 int success = 0, tmp1 = -1, tmp2 = -1, r; 549 550 /* Kludge: ensure there are fds free to receive the pty/tty */ 551 if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 || 552 (tmp2 = dup(pmonitor->m_recvfd)) == -1) { 553 error_f("cannot allocate fds for pty"); 554 if (tmp1 > 0) 555 close(tmp1); 556 if (tmp2 > 0) 557 close(tmp2); 558 return 0; 559 } 560 close(tmp1); 561 close(tmp2); 562 563 if ((m = sshbuf_new()) == NULL) 564 fatal_f("sshbuf_new failed"); 565 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, m); 566 567 debug3_f("waiting for MONITOR_ANS_PTY"); 568 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, m); 569 570 if ((r = sshbuf_get_u32(m, &success)) != 0) 571 fatal_fr(r, "parse success"); 572 if (success == 0) { 573 debug3_f("pty alloc failed"); 574 sshbuf_free(m); 575 return (0); 576 } 577 if ((r = sshbuf_get_cstring(m, &p, NULL)) != 0 || 578 (r = sshbuf_get_cstring(m, &msg, NULL)) != 0) 579 fatal_fr(r, "parse"); 580 sshbuf_free(m); 581 582 strlcpy(namebuf, p, namebuflen); /* Possible truncation */ 583 free(p); 584 585 if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0) 586 fatal_fr(r, "put loginmsg"); 587 free(msg); 588 589 if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 || 590 (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1) 591 fatal_f("receive fds failed"); 592 593 /* Success */ 594 return (1); 595 } 596 597 void 598 mm_session_pty_cleanup2(Session *s) 599 { 600 struct sshbuf *m; 601 int r; 602 603 if (s->ttyfd == -1) 604 return; 605 if ((m = sshbuf_new()) == NULL) 606 fatal_f("sshbuf_new failed"); 607 if ((r = sshbuf_put_cstring(m, s->tty)) != 0) 608 fatal_fr(r, "assmble"); 609 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, m); 610 sshbuf_free(m); 611 612 /* closed dup'ed master */ 613 if (s->ptymaster != -1 && close(s->ptymaster) == -1) 614 error("close(s->ptymaster/%d): %s", 615 s->ptymaster, strerror(errno)); 616 617 /* unlink pty from session */ 618 s->ttyfd = -1; 619 } 620 621 /* Request process termination */ 622 623 void 624 mm_terminate(void) 625 { 626 struct sshbuf *m; 627 628 if ((m = sshbuf_new()) == NULL) 629 fatal_f("sshbuf_new failed"); 630 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, m); 631 sshbuf_free(m); 632 } 633 634 static void 635 mm_chall_setup(char **name, char **infotxt, u_int *numprompts, 636 char ***prompts, u_int **echo_on) 637 { 638 *name = xstrdup(""); 639 *infotxt = xstrdup(""); 640 *numprompts = 1; 641 *prompts = xcalloc(*numprompts, sizeof(char *)); 642 *echo_on = xcalloc(*numprompts, sizeof(u_int)); 643 (*echo_on)[0] = 0; 644 } 645 646 int 647 mm_bsdauth_query(void *ctx, char **name, char **infotxt, 648 u_int *numprompts, char ***prompts, u_int **echo_on) 649 { 650 struct sshbuf *m; 651 u_int success; 652 char *challenge; 653 int r; 654 655 debug3_f("entering"); 656 657 if ((m = sshbuf_new()) == NULL) 658 fatal_f("sshbuf_new failed"); 659 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, m); 660 661 mm_request_receive_expect(pmonitor->m_recvfd, 662 MONITOR_ANS_BSDAUTHQUERY, m); 663 if ((r = sshbuf_get_u32(m, &success)) != 0) 664 fatal_fr(r, "parse success"); 665 if (success == 0) { 666 debug3_f("no challenge"); 667 sshbuf_free(m); 668 return (-1); 669 } 670 671 /* Get the challenge, and format the response */ 672 if ((r = sshbuf_get_cstring(m, &challenge, NULL)) != 0) 673 fatal_fr(r, "parse challenge"); 674 sshbuf_free(m); 675 676 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on); 677 (*prompts)[0] = challenge; 678 679 debug3_f("received challenge: %s", challenge); 680 681 return (0); 682 } 683 684 int 685 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses) 686 { 687 struct sshbuf *m; 688 int r, authok; 689 690 debug3_f("entering"); 691 if (numresponses != 1) 692 return (-1); 693 694 if ((m = sshbuf_new()) == NULL) 695 fatal_f("sshbuf_new failed"); 696 if ((r = sshbuf_put_cstring(m, responses[0])) != 0) 697 fatal_fr(r, "assemble"); 698 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, m); 699 700 mm_request_receive_expect(pmonitor->m_recvfd, 701 MONITOR_ANS_BSDAUTHRESPOND, m); 702 703 if ((r = sshbuf_get_u32(m, &authok)) != 0) 704 fatal_fr(r, "parse"); 705 sshbuf_free(m); 706 707 return ((authok == 0) ? -1 : 0); 708 } 709 710 #ifdef GSSAPI 711 OM_uint32 712 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid) 713 { 714 struct sshbuf *m; 715 OM_uint32 major; 716 int r; 717 718 /* Client doesn't get to see the context */ 719 *ctx = NULL; 720 721 if ((m = sshbuf_new()) == NULL) 722 fatal_f("sshbuf_new failed"); 723 if ((r = sshbuf_put_string(m, goid->elements, goid->length)) != 0) 724 fatal_fr(r, "assemble"); 725 726 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, m); 727 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, m); 728 729 if ((r = sshbuf_get_u32(m, &major)) != 0) 730 fatal_fr(r, "parse"); 731 732 sshbuf_free(m); 733 return (major); 734 } 735 736 OM_uint32 737 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in, 738 gss_buffer_desc *out, OM_uint32 *flagsp) 739 { 740 struct sshbuf *m; 741 OM_uint32 major; 742 u_int flags; 743 int r; 744 745 if ((m = sshbuf_new()) == NULL) 746 fatal_f("sshbuf_new failed"); 747 if ((r = sshbuf_put_string(m, in->value, in->length)) != 0) 748 fatal_fr(r, "assemble"); 749 750 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, m); 751 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, m); 752 753 if ((r = sshbuf_get_u32(m, &major)) != 0 || 754 (r = ssh_gssapi_get_buffer_desc(m, out)) != 0) 755 fatal_fr(r, "parse"); 756 if (flagsp != NULL) { 757 if ((r = sshbuf_get_u32(m, &flags)) != 0) 758 fatal_fr(r, "parse flags"); 759 *flagsp = flags; 760 } 761 762 sshbuf_free(m); 763 764 return (major); 765 } 766 767 OM_uint32 768 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic) 769 { 770 struct sshbuf *m; 771 OM_uint32 major; 772 int r; 773 774 if ((m = sshbuf_new()) == NULL) 775 fatal_f("sshbuf_new failed"); 776 if ((r = sshbuf_put_string(m, gssbuf->value, gssbuf->length)) != 0 || 777 (r = sshbuf_put_string(m, gssmic->value, gssmic->length)) != 0) 778 fatal_fr(r, "assemble"); 779 780 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, m); 781 mm_request_receive_expect(pmonitor->m_recvfd, 782 MONITOR_ANS_GSSCHECKMIC, m); 783 784 if ((r = sshbuf_get_u32(m, &major)) != 0) 785 fatal_fr(r, "parse"); 786 sshbuf_free(m); 787 return(major); 788 } 789 790 int 791 mm_ssh_gssapi_userok(char *user) 792 { 793 struct sshbuf *m; 794 int r, authenticated = 0; 795 796 if ((m = sshbuf_new()) == NULL) 797 fatal_f("sshbuf_new failed"); 798 799 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, m); 800 mm_request_receive_expect(pmonitor->m_recvfd, 801 MONITOR_ANS_GSSUSEROK, m); 802 803 if ((r = sshbuf_get_u32(m, &authenticated)) != 0) 804 fatal_fr(r, "parse"); 805 806 sshbuf_free(m); 807 debug3_f("user %sauthenticated", authenticated ? "" : "not "); 808 return (authenticated); 809 } 810 #endif /* GSSAPI */ 811