1 /* $OpenBSD: auth2.c,v 1.143 2017/06/24 06:34:38 djm Exp $ */ 2 /* 3 * Copyright (c) 2000 Markus Friedl. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "includes.h" 27 28 #include <sys/types.h> 29 #include <sys/stat.h> 30 #include <sys/uio.h> 31 32 #include <fcntl.h> 33 #include <limits.h> 34 #include <pwd.h> 35 #include <stdarg.h> 36 #include <string.h> 37 #include <unistd.h> 38 39 #include "atomicio.h" 40 #include "xmalloc.h" 41 #include "ssh2.h" 42 #include "packet.h" 43 #include "log.h" 44 #include "buffer.h" 45 #include "misc.h" 46 #include "servconf.h" 47 #include "compat.h" 48 #include "key.h" 49 #include "hostfile.h" 50 #include "auth.h" 51 #include "dispatch.h" 52 #include "pathnames.h" 53 #include "buffer.h" 54 55 #ifdef GSSAPI 56 #include "ssh-gss.h" 57 #endif 58 #include "monitor_wrap.h" 59 #include "ssherr.h" 60 61 /* import */ 62 extern ServerOptions options; 63 extern u_char *session_id2; 64 extern u_int session_id2_len; 65 extern Buffer loginmsg; 66 67 /* methods */ 68 69 extern Authmethod method_none; 70 extern Authmethod method_pubkey; 71 extern Authmethod method_passwd; 72 extern Authmethod method_kbdint; 73 extern Authmethod method_hostbased; 74 #ifdef GSSAPI 75 extern Authmethod method_gssapi; 76 #endif 77 78 Authmethod *authmethods[] = { 79 &method_none, 80 &method_pubkey, 81 #ifdef GSSAPI 82 &method_gssapi, 83 #endif 84 &method_passwd, 85 &method_kbdint, 86 &method_hostbased, 87 NULL 88 }; 89 90 /* protocol */ 91 92 static int input_service_request(int, u_int32_t, struct ssh *); 93 static int input_userauth_request(int, u_int32_t, struct ssh *); 94 95 /* helper */ 96 static Authmethod *authmethod_lookup(Authctxt *, const char *); 97 static char *authmethods_get(Authctxt *authctxt); 98 99 #define MATCH_NONE 0 /* method or submethod mismatch */ 100 #define MATCH_METHOD 1 /* method matches (no submethod specified) */ 101 #define MATCH_BOTH 2 /* method and submethod match */ 102 #define MATCH_PARTIAL 3 /* method matches, submethod can't be checked */ 103 static int list_starts_with(const char *, const char *, const char *); 104 105 char * 106 auth2_read_banner(void) 107 { 108 struct stat st; 109 char *banner = NULL; 110 size_t len, n; 111 int fd; 112 113 if ((fd = open(options.banner, O_RDONLY)) == -1) 114 return (NULL); 115 if (fstat(fd, &st) == -1) { 116 close(fd); 117 return (NULL); 118 } 119 if (st.st_size <= 0 || st.st_size > 1*1024*1024) { 120 close(fd); 121 return (NULL); 122 } 123 124 len = (size_t)st.st_size; /* truncate */ 125 banner = xmalloc(len + 1); 126 n = atomicio(read, fd, banner, len); 127 close(fd); 128 129 if (n != len) { 130 free(banner); 131 return (NULL); 132 } 133 banner[n] = '\0'; 134 135 return (banner); 136 } 137 138 void 139 userauth_send_banner(const char *msg) 140 { 141 if (datafellows & SSH_BUG_BANNER) 142 return; 143 144 packet_start(SSH2_MSG_USERAUTH_BANNER); 145 packet_put_cstring(msg); 146 packet_put_cstring(""); /* language, unused */ 147 packet_send(); 148 debug("%s: sent", __func__); 149 } 150 151 static void 152 userauth_banner(void) 153 { 154 char *banner = NULL; 155 156 if (options.banner == NULL || (datafellows & SSH_BUG_BANNER) != 0) 157 return; 158 159 if ((banner = PRIVSEP(auth2_read_banner())) == NULL) 160 goto done; 161 userauth_send_banner(banner); 162 163 done: 164 free(banner); 165 } 166 167 /* 168 * loop until authctxt->success == TRUE 169 */ 170 void 171 do_authentication2(Authctxt *authctxt) 172 { 173 struct ssh *ssh = active_state; /* XXX */ 174 ssh->authctxt = authctxt; /* XXX move to caller */ 175 ssh_dispatch_init(ssh, &dispatch_protocol_error); 176 ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_REQUEST, &input_service_request); 177 ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt->success); 178 ssh->authctxt = NULL; 179 } 180 181 /*ARGSUSED*/ 182 static int 183 input_service_request(int type, u_int32_t seq, struct ssh *ssh) 184 { 185 Authctxt *authctxt = ssh->authctxt; 186 u_int len; 187 int acceptit = 0; 188 char *service = packet_get_cstring(&len); 189 packet_check_eom(); 190 191 if (authctxt == NULL) 192 fatal("input_service_request: no authctxt"); 193 194 if (strcmp(service, "ssh-userauth") == 0) { 195 if (!authctxt->success) { 196 acceptit = 1; 197 /* now we can handle user-auth requests */ 198 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request); 199 } 200 } 201 /* XXX all other service requests are denied */ 202 203 if (acceptit) { 204 packet_start(SSH2_MSG_SERVICE_ACCEPT); 205 packet_put_cstring(service); 206 packet_send(); 207 packet_write_wait(); 208 } else { 209 debug("bad service request %s", service); 210 packet_disconnect("bad service request %s", service); 211 } 212 free(service); 213 return 0; 214 } 215 216 /*ARGSUSED*/ 217 static int 218 input_userauth_request(int type, u_int32_t seq, struct ssh *ssh) 219 { 220 Authctxt *authctxt = ssh->authctxt; 221 Authmethod *m = NULL; 222 char *user, *service, *method, *style = NULL; 223 int authenticated = 0; 224 225 if (authctxt == NULL) 226 fatal("input_userauth_request: no authctxt"); 227 228 user = packet_get_cstring(NULL); 229 service = packet_get_cstring(NULL); 230 method = packet_get_cstring(NULL); 231 debug("userauth-request for user %s service %s method %s", user, service, method); 232 debug("attempt %d failures %d", authctxt->attempt, authctxt->failures); 233 234 if ((style = strchr(user, ':')) != NULL) 235 *style++ = 0; 236 237 if (authctxt->attempt++ == 0) { 238 /* setup auth context */ 239 authctxt->pw = PRIVSEP(getpwnamallow(user)); 240 authctxt->user = xstrdup(user); 241 if (authctxt->pw && strcmp(service, "ssh-connection")==0) { 242 authctxt->valid = 1; 243 debug2("%s: setting up authctxt for %s", 244 __func__, user); 245 } else { 246 /* Invalid user, fake password information */ 247 authctxt->pw = fakepw(); 248 #ifdef SSH_AUDIT_EVENTS 249 PRIVSEP(audit_event(SSH_INVALID_USER)); 250 #endif 251 } 252 #ifdef USE_PAM 253 if (options.use_pam) 254 PRIVSEP(start_pam(authctxt)); 255 #endif 256 ssh_packet_set_log_preamble(ssh, "%suser %s", 257 authctxt->valid ? "authenticating " : "invalid ", user); 258 setproctitle("%s%s", authctxt->valid ? user : "unknown", 259 use_privsep ? " [net]" : ""); 260 authctxt->service = xstrdup(service); 261 authctxt->style = style ? xstrdup(style) : NULL; 262 if (use_privsep) 263 mm_inform_authserv(service, style); 264 userauth_banner(); 265 if (auth2_setup_methods_lists(authctxt) != 0) 266 packet_disconnect("no authentication methods enabled"); 267 } else if (strcmp(user, authctxt->user) != 0 || 268 strcmp(service, authctxt->service) != 0) { 269 packet_disconnect("Change of username or service not allowed: " 270 "(%s,%s) -> (%s,%s)", 271 authctxt->user, authctxt->service, user, service); 272 } 273 /* reset state */ 274 auth2_challenge_stop(ssh); 275 276 #ifdef GSSAPI 277 /* XXX move to auth2_gssapi_stop() */ 278 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL); 279 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL); 280 #endif 281 282 auth2_authctxt_reset_info(authctxt); 283 authctxt->postponed = 0; 284 authctxt->server_caused_failure = 0; 285 286 /* try to authenticate user */ 287 m = authmethod_lookup(authctxt, method); 288 if (m != NULL && authctxt->failures < options.max_authtries) { 289 debug2("input_userauth_request: try method %s", method); 290 authenticated = m->userauth(ssh); 291 } 292 userauth_finish(ssh, authenticated, method, NULL); 293 294 free(service); 295 free(user); 296 free(method); 297 return 0; 298 } 299 300 void 301 userauth_finish(struct ssh *ssh, int authenticated, const char *method, 302 const char *submethod) 303 { 304 Authctxt *authctxt = ssh->authctxt; 305 char *methods; 306 int partial = 0; 307 308 if (!authctxt->valid && authenticated) 309 fatal("INTERNAL ERROR: authenticated invalid user %s", 310 authctxt->user); 311 if (authenticated && authctxt->postponed) 312 fatal("INTERNAL ERROR: authenticated and postponed"); 313 314 /* Special handling for root */ 315 if (authenticated && authctxt->pw->pw_uid == 0 && 316 !auth_root_allowed(method)) { 317 authenticated = 0; 318 #ifdef SSH_AUDIT_EVENTS 319 PRIVSEP(audit_event(SSH_LOGIN_ROOT_DENIED)); 320 #endif 321 } 322 323 if (authenticated && options.num_auth_methods != 0) { 324 if (!auth2_update_methods_lists(authctxt, method, submethod)) { 325 authenticated = 0; 326 partial = 1; 327 } 328 } 329 330 /* Log before sending the reply */ 331 auth_log(authctxt, authenticated, partial, method, submethod); 332 333 /* Update information exposed to session */ 334 if (authenticated || partial) 335 auth2_update_session_info(authctxt, method, submethod); 336 337 if (authctxt->postponed) 338 return; 339 340 #ifdef USE_PAM 341 if (options.use_pam && authenticated) { 342 if (!PRIVSEP(do_pam_account())) { 343 /* if PAM returned a message, send it to the user */ 344 if (buffer_len(&loginmsg) > 0) { 345 buffer_append(&loginmsg, "\0", 1); 346 userauth_send_banner(buffer_ptr(&loginmsg)); 347 packet_write_wait(); 348 } 349 fatal("Access denied for user %s by PAM account " 350 "configuration", authctxt->user); 351 } 352 } 353 #endif 354 355 #ifdef _UNICOS 356 if (authenticated && cray_access_denied(authctxt->user)) { 357 authenticated = 0; 358 fatal("Access denied for user %s.", authctxt->user); 359 } 360 #endif /* _UNICOS */ 361 362 if (authenticated == 1) { 363 /* turn off userauth */ 364 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore); 365 packet_start(SSH2_MSG_USERAUTH_SUCCESS); 366 packet_send(); 367 packet_write_wait(); 368 /* now we can break out */ 369 authctxt->success = 1; 370 ssh_packet_set_log_preamble(ssh, "user %s", authctxt->user); 371 } else { 372 373 /* Allow initial try of "none" auth without failure penalty */ 374 if (!partial && !authctxt->server_caused_failure && 375 (authctxt->attempt > 1 || strcmp(method, "none") != 0)) 376 authctxt->failures++; 377 if (authctxt->failures >= options.max_authtries) { 378 #ifdef SSH_AUDIT_EVENTS 379 PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES)); 380 #endif 381 auth_maxtries_exceeded(authctxt); 382 } 383 methods = authmethods_get(authctxt); 384 debug3("%s: failure partial=%d next methods=\"%s\"", __func__, 385 partial, methods); 386 packet_start(SSH2_MSG_USERAUTH_FAILURE); 387 packet_put_cstring(methods); 388 packet_put_char(partial); 389 packet_send(); 390 packet_write_wait(); 391 free(methods); 392 } 393 } 394 395 /* 396 * Checks whether method is allowed by at least one AuthenticationMethods 397 * methods list. Returns 1 if allowed, or no methods lists configured. 398 * 0 otherwise. 399 */ 400 int 401 auth2_method_allowed(Authctxt *authctxt, const char *method, 402 const char *submethod) 403 { 404 u_int i; 405 406 /* 407 * NB. authctxt->num_auth_methods might be zero as a result of 408 * auth2_setup_methods_lists(), so check the configuration. 409 */ 410 if (options.num_auth_methods == 0) 411 return 1; 412 for (i = 0; i < authctxt->num_auth_methods; i++) { 413 if (list_starts_with(authctxt->auth_methods[i], method, 414 submethod) != MATCH_NONE) 415 return 1; 416 } 417 return 0; 418 } 419 420 static char * 421 authmethods_get(Authctxt *authctxt) 422 { 423 Buffer b; 424 char *list; 425 u_int i; 426 427 buffer_init(&b); 428 for (i = 0; authmethods[i] != NULL; i++) { 429 if (strcmp(authmethods[i]->name, "none") == 0) 430 continue; 431 if (authmethods[i]->enabled == NULL || 432 *(authmethods[i]->enabled) == 0) 433 continue; 434 if (!auth2_method_allowed(authctxt, authmethods[i]->name, 435 NULL)) 436 continue; 437 if (buffer_len(&b) > 0) 438 buffer_append(&b, ",", 1); 439 buffer_append(&b, authmethods[i]->name, 440 strlen(authmethods[i]->name)); 441 } 442 if ((list = sshbuf_dup_string(&b)) == NULL) 443 fatal("%s: sshbuf_dup_string failed", __func__); 444 buffer_free(&b); 445 return list; 446 } 447 448 static Authmethod * 449 authmethod_lookup(Authctxt *authctxt, const char *name) 450 { 451 int i; 452 453 if (name != NULL) 454 for (i = 0; authmethods[i] != NULL; i++) 455 if (authmethods[i]->enabled != NULL && 456 *(authmethods[i]->enabled) != 0 && 457 strcmp(name, authmethods[i]->name) == 0 && 458 auth2_method_allowed(authctxt, 459 authmethods[i]->name, NULL)) 460 return authmethods[i]; 461 debug2("Unrecognized authentication method name: %s", 462 name ? name : "NULL"); 463 return NULL; 464 } 465 466 /* 467 * Check a comma-separated list of methods for validity. Is need_enable is 468 * non-zero, then also require that the methods are enabled. 469 * Returns 0 on success or -1 if the methods list is invalid. 470 */ 471 int 472 auth2_methods_valid(const char *_methods, int need_enable) 473 { 474 char *methods, *omethods, *method, *p; 475 u_int i, found; 476 int ret = -1; 477 478 if (*_methods == '\0') { 479 error("empty authentication method list"); 480 return -1; 481 } 482 omethods = methods = xstrdup(_methods); 483 while ((method = strsep(&methods, ",")) != NULL) { 484 for (found = i = 0; !found && authmethods[i] != NULL; i++) { 485 if ((p = strchr(method, ':')) != NULL) 486 *p = '\0'; 487 if (strcmp(method, authmethods[i]->name) != 0) 488 continue; 489 if (need_enable) { 490 if (authmethods[i]->enabled == NULL || 491 *(authmethods[i]->enabled) == 0) { 492 error("Disabled method \"%s\" in " 493 "AuthenticationMethods list \"%s\"", 494 method, _methods); 495 goto out; 496 } 497 } 498 found = 1; 499 break; 500 } 501 if (!found) { 502 error("Unknown authentication method \"%s\" in list", 503 method); 504 goto out; 505 } 506 } 507 ret = 0; 508 out: 509 free(omethods); 510 return ret; 511 } 512 513 /* 514 * Prune the AuthenticationMethods supplied in the configuration, removing 515 * any methods lists that include disabled methods. Note that this might 516 * leave authctxt->num_auth_methods == 0, even when multiple required auth 517 * has been requested. For this reason, all tests for whether multiple is 518 * enabled should consult options.num_auth_methods directly. 519 */ 520 int 521 auth2_setup_methods_lists(Authctxt *authctxt) 522 { 523 u_int i; 524 525 if (options.num_auth_methods == 0) 526 return 0; 527 debug3("%s: checking methods", __func__); 528 authctxt->auth_methods = xcalloc(options.num_auth_methods, 529 sizeof(*authctxt->auth_methods)); 530 authctxt->num_auth_methods = 0; 531 for (i = 0; i < options.num_auth_methods; i++) { 532 if (auth2_methods_valid(options.auth_methods[i], 1) != 0) { 533 logit("Authentication methods list \"%s\" contains " 534 "disabled method, skipping", 535 options.auth_methods[i]); 536 continue; 537 } 538 debug("authentication methods list %d: %s", 539 authctxt->num_auth_methods, options.auth_methods[i]); 540 authctxt->auth_methods[authctxt->num_auth_methods++] = 541 xstrdup(options.auth_methods[i]); 542 } 543 if (authctxt->num_auth_methods == 0) { 544 error("No AuthenticationMethods left after eliminating " 545 "disabled methods"); 546 return -1; 547 } 548 return 0; 549 } 550 551 static int 552 list_starts_with(const char *methods, const char *method, 553 const char *submethod) 554 { 555 size_t l = strlen(method); 556 int match; 557 const char *p; 558 559 if (strncmp(methods, method, l) != 0) 560 return MATCH_NONE; 561 p = methods + l; 562 match = MATCH_METHOD; 563 if (*p == ':') { 564 if (!submethod) 565 return MATCH_PARTIAL; 566 l = strlen(submethod); 567 p += 1; 568 if (strncmp(submethod, p, l)) 569 return MATCH_NONE; 570 p += l; 571 match = MATCH_BOTH; 572 } 573 if (*p != ',' && *p != '\0') 574 return MATCH_NONE; 575 return match; 576 } 577 578 /* 579 * Remove method from the start of a comma-separated list of methods. 580 * Returns 0 if the list of methods did not start with that method or 1 581 * if it did. 582 */ 583 static int 584 remove_method(char **methods, const char *method, const char *submethod) 585 { 586 char *omethods = *methods, *p; 587 size_t l = strlen(method); 588 int match; 589 590 match = list_starts_with(omethods, method, submethod); 591 if (match != MATCH_METHOD && match != MATCH_BOTH) 592 return 0; 593 p = omethods + l; 594 if (submethod && match == MATCH_BOTH) 595 p += 1 + strlen(submethod); /* include colon */ 596 if (*p == ',') 597 p++; 598 *methods = xstrdup(p); 599 free(omethods); 600 return 1; 601 } 602 603 /* 604 * Called after successful authentication. Will remove the successful method 605 * from the start of each list in which it occurs. If it was the last method 606 * in any list, then authentication is deemed successful. 607 * Returns 1 if the method completed any authentication list or 0 otherwise. 608 */ 609 int 610 auth2_update_methods_lists(Authctxt *authctxt, const char *method, 611 const char *submethod) 612 { 613 u_int i, found = 0; 614 615 debug3("%s: updating methods list after \"%s\"", __func__, method); 616 for (i = 0; i < authctxt->num_auth_methods; i++) { 617 if (!remove_method(&(authctxt->auth_methods[i]), method, 618 submethod)) 619 continue; 620 found = 1; 621 if (*authctxt->auth_methods[i] == '\0') { 622 debug2("authentication methods list %d complete", i); 623 return 1; 624 } 625 debug3("authentication methods list %d remaining: \"%s\"", 626 i, authctxt->auth_methods[i]); 627 } 628 /* This should not happen, but would be bad if it did */ 629 if (!found) 630 fatal("%s: method not in AuthenticationMethods", __func__); 631 return 0; 632 } 633 634 /* Reset method-specific information */ 635 void auth2_authctxt_reset_info(Authctxt *authctxt) 636 { 637 sshkey_free(authctxt->auth_method_key); 638 free(authctxt->auth_method_info); 639 authctxt->auth_method_key = NULL; 640 authctxt->auth_method_info = NULL; 641 } 642 643 /* Record auth method-specific information for logs */ 644 void 645 auth2_record_info(Authctxt *authctxt, const char *fmt, ...) 646 { 647 va_list ap; 648 int i; 649 650 free(authctxt->auth_method_info); 651 authctxt->auth_method_info = NULL; 652 653 va_start(ap, fmt); 654 i = vasprintf(&authctxt->auth_method_info, fmt, ap); 655 va_end(ap); 656 657 if (i < 0 || authctxt->auth_method_info == NULL) 658 fatal("%s: vasprintf failed", __func__); 659 } 660 661 /* 662 * Records a public key used in authentication. This is used for logging 663 * and to ensure that the same key is not subsequently accepted again for 664 * multiple authentication. 665 */ 666 void 667 auth2_record_key(Authctxt *authctxt, int authenticated, 668 const struct sshkey *key) 669 { 670 struct sshkey **tmp, *dup; 671 int r; 672 673 if ((r = sshkey_demote(key, &dup)) != 0) 674 fatal("%s: copy key: %s", __func__, ssh_err(r)); 675 sshkey_free(authctxt->auth_method_key); 676 authctxt->auth_method_key = dup; 677 678 if (!authenticated) 679 return; 680 681 /* If authenticated, make sure we don't accept this key again */ 682 if ((r = sshkey_demote(key, &dup)) != 0) 683 fatal("%s: copy key: %s", __func__, ssh_err(r)); 684 if (authctxt->nprev_keys >= INT_MAX || 685 (tmp = recallocarray(authctxt->prev_keys, authctxt->nprev_keys, 686 authctxt->nprev_keys + 1, sizeof(*authctxt->prev_keys))) == NULL) 687 fatal("%s: reallocarray failed", __func__); 688 authctxt->prev_keys = tmp; 689 authctxt->prev_keys[authctxt->nprev_keys] = dup; 690 authctxt->nprev_keys++; 691 692 } 693 694 /* Checks whether a key has already been previously used for authentication */ 695 int 696 auth2_key_already_used(Authctxt *authctxt, const struct sshkey *key) 697 { 698 u_int i; 699 char *fp; 700 701 for (i = 0; i < authctxt->nprev_keys; i++) { 702 if (sshkey_equal_public(key, authctxt->prev_keys[i])) { 703 fp = sshkey_fingerprint(authctxt->prev_keys[i], 704 options.fingerprint_hash, SSH_FP_DEFAULT); 705 debug3("%s: key already used: %s %s", __func__, 706 sshkey_type(authctxt->prev_keys[i]), 707 fp == NULL ? "UNKNOWN" : fp); 708 free(fp); 709 return 1; 710 } 711 } 712 return 0; 713 } 714 715 /* 716 * Updates authctxt->session_info with details of authentication. Should be 717 * whenever an authentication method succeeds. 718 */ 719 void 720 auth2_update_session_info(Authctxt *authctxt, const char *method, 721 const char *submethod) 722 { 723 int r; 724 725 if (authctxt->session_info == NULL) { 726 if ((authctxt->session_info = sshbuf_new()) == NULL) 727 fatal("%s: sshbuf_new", __func__); 728 } 729 730 /* Append method[/submethod] */ 731 if ((r = sshbuf_putf(authctxt->session_info, "%s%s%s", 732 method, submethod == NULL ? "" : "/", 733 submethod == NULL ? "" : submethod)) != 0) 734 fatal("%s: append method: %s", __func__, ssh_err(r)); 735 736 /* Append key if present */ 737 if (authctxt->auth_method_key != NULL) { 738 if ((r = sshbuf_put_u8(authctxt->session_info, ' ')) != 0 || 739 (r = sshkey_format_text(authctxt->auth_method_key, 740 authctxt->session_info)) != 0) 741 fatal("%s: append key: %s", __func__, ssh_err(r)); 742 } 743 744 if (authctxt->auth_method_info != NULL) { 745 /* Ensure no ambiguity here */ 746 if (strchr(authctxt->auth_method_info, '\n') != NULL) 747 fatal("%s: auth_method_info contains \\n", __func__); 748 if ((r = sshbuf_put_u8(authctxt->session_info, ' ')) != 0 || 749 (r = sshbuf_putf(authctxt->session_info, "%s", 750 authctxt->auth_method_info)) != 0) { 751 fatal("%s: append method info: %s", 752 __func__, ssh_err(r)); 753 } 754 } 755 if ((r = sshbuf_put_u8(authctxt->session_info, '\n')) != 0) 756 fatal("%s: append: %s", __func__, ssh_err(r)); 757 } 758 759