1 /* $OpenBSD: auth2.c,v 1.151 2019/01/17 04:20:53 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 27 #include <sys/types.h> 28 #include <sys/stat.h> 29 #include <sys/uio.h> 30 31 #include <fcntl.h> 32 #include <limits.h> 33 #include <pwd.h> 34 #include <stdarg.h> 35 #include <string.h> 36 #include <unistd.h> 37 #include <time.h> 38 39 #include "atomicio.h" 40 #include "xmalloc.h" 41 #include "ssh2.h" 42 #include "packet.h" 43 #include "log.h" 44 #include "sshbuf.h" 45 #include "misc.h" 46 #include "servconf.h" 47 #include "compat.h" 48 #include "sshkey.h" 49 #include "hostfile.h" 50 #include "auth.h" 51 #include "dispatch.h" 52 #include "pathnames.h" 53 #ifdef GSSAPI 54 #include "ssh-gss.h" 55 #endif 56 #include "monitor_wrap.h" 57 #include "ssherr.h" 58 #include "digest.h" 59 60 /* import */ 61 extern ServerOptions options; 62 extern u_char *session_id2; 63 extern u_int session_id2_len; 64 65 /* methods */ 66 67 extern Authmethod method_none; 68 extern Authmethod method_pubkey; 69 extern Authmethod method_passwd; 70 extern Authmethod method_kbdint; 71 extern Authmethod method_hostbased; 72 #ifdef GSSAPI 73 extern Authmethod method_gssapi; 74 #endif 75 76 Authmethod *authmethods[] = { 77 &method_none, 78 &method_pubkey, 79 #ifdef GSSAPI 80 &method_gssapi, 81 #endif 82 &method_passwd, 83 &method_kbdint, 84 &method_hostbased, 85 NULL 86 }; 87 88 /* protocol */ 89 90 static int input_service_request(int, u_int32_t, struct ssh *); 91 static int input_userauth_request(int, u_int32_t, struct ssh *); 92 93 /* helper */ 94 static Authmethod *authmethod_lookup(Authctxt *, const char *); 95 static char *authmethods_get(Authctxt *authctxt); 96 97 #define MATCH_NONE 0 /* method or submethod mismatch */ 98 #define MATCH_METHOD 1 /* method matches (no submethod specified) */ 99 #define MATCH_BOTH 2 /* method and submethod match */ 100 #define MATCH_PARTIAL 3 /* method matches, submethod can't be checked */ 101 static int list_starts_with(const char *, const char *, const char *); 102 103 char * 104 auth2_read_banner(void) 105 { 106 struct stat st; 107 char *banner = NULL; 108 size_t len, n; 109 int fd; 110 111 if ((fd = open(options.banner, O_RDONLY)) == -1) 112 return (NULL); 113 if (fstat(fd, &st) == -1) { 114 close(fd); 115 return (NULL); 116 } 117 if (st.st_size <= 0 || st.st_size > 1*1024*1024) { 118 close(fd); 119 return (NULL); 120 } 121 122 len = (size_t)st.st_size; /* truncate */ 123 banner = xmalloc(len + 1); 124 n = atomicio(read, fd, banner, len); 125 close(fd); 126 127 if (n != len) { 128 free(banner); 129 return (NULL); 130 } 131 banner[n] = '\0'; 132 133 return (banner); 134 } 135 136 static void 137 userauth_banner(void) 138 { 139 char *banner = NULL; 140 141 if (options.banner == NULL) 142 return; 143 144 if ((banner = PRIVSEP(auth2_read_banner())) == NULL) 145 goto done; 146 147 packet_start(SSH2_MSG_USERAUTH_BANNER); 148 packet_put_cstring(banner); 149 packet_put_cstring(""); /* language, unused */ 150 packet_send(); 151 debug("userauth_banner: sent"); 152 done: 153 free(banner); 154 } 155 156 /* 157 * loop until authctxt->success == TRUE 158 */ 159 void 160 do_authentication2(Authctxt *authctxt) 161 { 162 struct ssh *ssh = active_state; /* XXX */ 163 ssh->authctxt = authctxt; /* XXX move to caller */ 164 ssh_dispatch_init(ssh, &dispatch_protocol_error); 165 ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_REQUEST, &input_service_request); 166 ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt->success); 167 ssh->authctxt = NULL; 168 } 169 170 /*ARGSUSED*/ 171 static int 172 input_service_request(int type, u_int32_t seq, struct ssh *ssh) 173 { 174 Authctxt *authctxt = ssh->authctxt; 175 u_int len; 176 int acceptit = 0; 177 char *service = packet_get_cstring(&len); 178 packet_check_eom(); 179 180 if (authctxt == NULL) 181 fatal("input_service_request: no authctxt"); 182 183 if (strcmp(service, "ssh-userauth") == 0) { 184 if (!authctxt->success) { 185 acceptit = 1; 186 /* now we can handle user-auth requests */ 187 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request); 188 } 189 } 190 /* XXX all other service requests are denied */ 191 192 if (acceptit) { 193 packet_start(SSH2_MSG_SERVICE_ACCEPT); 194 packet_put_cstring(service); 195 packet_send(); 196 packet_write_wait(); 197 } else { 198 debug("bad service request %s", service); 199 packet_disconnect("bad service request %s", service); 200 } 201 free(service); 202 return 0; 203 } 204 205 #define MIN_FAIL_DELAY_SECONDS 0.005 206 static double 207 user_specific_delay(const char *user) 208 { 209 char b[512]; 210 size_t len = ssh_digest_bytes(SSH_DIGEST_SHA512); 211 u_char *hash = xmalloc(len); 212 double delay; 213 214 (void)snprintf(b, sizeof b, "%llu%s", 215 (unsigned long long)options.timing_secret, user); 216 if (ssh_digest_memory(SSH_DIGEST_SHA512, b, strlen(b), hash, len) != 0) 217 fatal("%s: ssh_digest_memory", __func__); 218 /* 0-4.2 ms of delay */ 219 delay = (double)PEEK_U32(hash) / 1000 / 1000 / 1000 / 1000; 220 freezero(hash, len); 221 debug3("%s: user specific delay %0.3lfms", __func__, delay/1000); 222 return MIN_FAIL_DELAY_SECONDS + delay; 223 } 224 225 static void 226 ensure_minimum_time_since(double start, double seconds) 227 { 228 struct timespec ts; 229 double elapsed = monotime_double() - start, req = seconds, remain; 230 231 /* if we've already passed the requested time, scale up */ 232 while ((remain = seconds - elapsed) < 0.0) 233 seconds *= 2; 234 235 ts.tv_sec = remain; 236 ts.tv_nsec = (remain - ts.tv_sec) * 1000000000; 237 debug3("%s: elapsed %0.3lfms, delaying %0.3lfms (requested %0.3lfms)", 238 __func__, elapsed*1000, remain*1000, req*1000); 239 nanosleep(&ts, NULL); 240 } 241 242 /*ARGSUSED*/ 243 static int 244 input_userauth_request(int type, u_int32_t seq, struct ssh *ssh) 245 { 246 Authctxt *authctxt = ssh->authctxt; 247 Authmethod *m = NULL; 248 char *user, *service, *method, *style = NULL; 249 int authenticated = 0; 250 double tstart = monotime_double(); 251 252 if (authctxt == NULL) 253 fatal("input_userauth_request: no authctxt"); 254 255 user = packet_get_cstring(NULL); 256 service = packet_get_cstring(NULL); 257 method = packet_get_cstring(NULL); 258 debug("userauth-request for user %s service %s method %s", user, service, method); 259 debug("attempt %d failures %d", authctxt->attempt, authctxt->failures); 260 261 if ((style = strchr(user, ':')) != NULL) 262 *style++ = 0; 263 264 if (authctxt->attempt++ == 0) { 265 /* setup auth context */ 266 authctxt->pw = PRIVSEP(getpwnamallow(user)); 267 if (authctxt->pw && strcmp(service, "ssh-connection")==0) { 268 authctxt->valid = 1; 269 debug2("%s: setting up authctxt for %s", 270 __func__, user); 271 } else { 272 /* Invalid user, fake password information */ 273 authctxt->pw = fakepw(); 274 } 275 ssh_packet_set_log_preamble(ssh, "%suser %s", 276 authctxt->valid ? "authenticating " : "invalid ", user); 277 setproctitle("%s%s", authctxt->valid ? user : "unknown", 278 use_privsep ? " [net]" : ""); 279 authctxt->user = xstrdup(user); 280 authctxt->service = xstrdup(service); 281 authctxt->style = style ? xstrdup(style) : NULL; 282 if (use_privsep) 283 mm_inform_authserv(service, style); 284 userauth_banner(); 285 if (auth2_setup_methods_lists(authctxt) != 0) 286 packet_disconnect("no authentication methods enabled"); 287 } else if (strcmp(user, authctxt->user) != 0 || 288 strcmp(service, authctxt->service) != 0) { 289 packet_disconnect("Change of username or service not allowed: " 290 "(%s,%s) -> (%s,%s)", 291 authctxt->user, authctxt->service, user, service); 292 } 293 /* reset state */ 294 auth2_challenge_stop(ssh); 295 296 #ifdef GSSAPI 297 /* XXX move to auth2_gssapi_stop() */ 298 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL); 299 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL); 300 #endif 301 302 auth2_authctxt_reset_info(authctxt); 303 authctxt->postponed = 0; 304 authctxt->server_caused_failure = 0; 305 306 /* try to authenticate user */ 307 m = authmethod_lookup(authctxt, method); 308 if (m != NULL && authctxt->failures < options.max_authtries) { 309 debug2("input_userauth_request: try method %s", method); 310 authenticated = m->userauth(ssh); 311 } 312 if (!authctxt->authenticated) 313 ensure_minimum_time_since(tstart, 314 user_specific_delay(authctxt->user)); 315 userauth_finish(ssh, authenticated, method, NULL); 316 317 free(service); 318 free(user); 319 free(method); 320 return 0; 321 } 322 323 void 324 userauth_finish(struct ssh *ssh, int authenticated, const char *method, 325 const char *submethod) 326 { 327 Authctxt *authctxt = ssh->authctxt; 328 char *methods; 329 int partial = 0; 330 331 if (!authctxt->valid && authenticated) 332 fatal("INTERNAL ERROR: authenticated invalid user %s", 333 authctxt->user); 334 if (authenticated && authctxt->postponed) 335 fatal("INTERNAL ERROR: authenticated and postponed"); 336 337 /* Special handling for root */ 338 if (authenticated && authctxt->pw->pw_uid == 0 && 339 !auth_root_allowed(ssh, method)) 340 authenticated = 0; 341 342 if (authenticated && options.num_auth_methods != 0) { 343 if (!auth2_update_methods_lists(authctxt, method, submethod)) { 344 authenticated = 0; 345 partial = 1; 346 } 347 } 348 349 /* Log before sending the reply */ 350 auth_log(authctxt, authenticated, partial, method, submethod); 351 352 /* Update information exposed to session */ 353 if (authenticated || partial) 354 auth2_update_session_info(authctxt, method, submethod); 355 356 if (authctxt->postponed) 357 return; 358 359 if (authenticated == 1) { 360 /* turn off userauth */ 361 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore); 362 packet_start(SSH2_MSG_USERAUTH_SUCCESS); 363 packet_send(); 364 packet_write_wait(); 365 /* now we can break out */ 366 authctxt->success = 1; 367 ssh_packet_set_log_preamble(ssh, "user %s", authctxt->user); 368 } else { 369 /* Allow initial try of "none" auth without failure penalty */ 370 if (!partial && !authctxt->server_caused_failure && 371 (authctxt->attempt > 1 || strcmp(method, "none") != 0)) 372 authctxt->failures++; 373 if (authctxt->failures >= options.max_authtries) 374 auth_maxtries_exceeded(authctxt); 375 methods = authmethods_get(authctxt); 376 debug3("%s: failure partial=%d next methods=\"%s\"", __func__, 377 partial, methods); 378 packet_start(SSH2_MSG_USERAUTH_FAILURE); 379 packet_put_cstring(methods); 380 packet_put_char(partial); 381 packet_send(); 382 packet_write_wait(); 383 free(methods); 384 } 385 } 386 387 /* 388 * Checks whether method is allowed by at least one AuthenticationMethods 389 * methods list. Returns 1 if allowed, or no methods lists configured. 390 * 0 otherwise. 391 */ 392 int 393 auth2_method_allowed(Authctxt *authctxt, const char *method, 394 const char *submethod) 395 { 396 u_int i; 397 398 /* 399 * NB. authctxt->num_auth_methods might be zero as a result of 400 * auth2_setup_methods_lists(), so check the configuration. 401 */ 402 if (options.num_auth_methods == 0) 403 return 1; 404 for (i = 0; i < authctxt->num_auth_methods; i++) { 405 if (list_starts_with(authctxt->auth_methods[i], method, 406 submethod) != MATCH_NONE) 407 return 1; 408 } 409 return 0; 410 } 411 412 static char * 413 authmethods_get(Authctxt *authctxt) 414 { 415 struct sshbuf *b; 416 char *list; 417 int i, r; 418 419 if ((b = sshbuf_new()) == NULL) 420 fatal("%s: sshbuf_new failed", __func__); 421 for (i = 0; authmethods[i] != NULL; i++) { 422 if (strcmp(authmethods[i]->name, "none") == 0) 423 continue; 424 if (authmethods[i]->enabled == NULL || 425 *(authmethods[i]->enabled) == 0) 426 continue; 427 if (!auth2_method_allowed(authctxt, authmethods[i]->name, 428 NULL)) 429 continue; 430 if ((r = sshbuf_putf(b, "%s%s", sshbuf_len(b) ? "," : "", 431 authmethods[i]->name)) != 0) 432 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 433 } 434 if ((list = sshbuf_dup_string(b)) == NULL) 435 fatal("%s: sshbuf_dup_string failed", __func__); 436 sshbuf_free(b); 437 return list; 438 } 439 440 static Authmethod * 441 authmethod_lookup(Authctxt *authctxt, const char *name) 442 { 443 int i; 444 445 if (name != NULL) 446 for (i = 0; authmethods[i] != NULL; i++) 447 if (authmethods[i]->enabled != NULL && 448 *(authmethods[i]->enabled) != 0 && 449 strcmp(name, authmethods[i]->name) == 0 && 450 auth2_method_allowed(authctxt, 451 authmethods[i]->name, NULL)) 452 return authmethods[i]; 453 debug2("Unrecognized authentication method name: %s", 454 name ? name : "NULL"); 455 return NULL; 456 } 457 458 /* 459 * Check a comma-separated list of methods for validity. Is need_enable is 460 * non-zero, then also require that the methods are enabled. 461 * Returns 0 on success or -1 if the methods list is invalid. 462 */ 463 int 464 auth2_methods_valid(const char *_methods, int need_enable) 465 { 466 char *methods, *omethods, *method, *p; 467 u_int i, found; 468 int ret = -1; 469 470 if (*_methods == '\0') { 471 error("empty authentication method list"); 472 return -1; 473 } 474 omethods = methods = xstrdup(_methods); 475 while ((method = strsep(&methods, ",")) != NULL) { 476 for (found = i = 0; !found && authmethods[i] != NULL; i++) { 477 if ((p = strchr(method, ':')) != NULL) 478 *p = '\0'; 479 if (strcmp(method, authmethods[i]->name) != 0) 480 continue; 481 if (need_enable) { 482 if (authmethods[i]->enabled == NULL || 483 *(authmethods[i]->enabled) == 0) { 484 error("Disabled method \"%s\" in " 485 "AuthenticationMethods list \"%s\"", 486 method, _methods); 487 goto out; 488 } 489 } 490 found = 1; 491 break; 492 } 493 if (!found) { 494 error("Unknown authentication method \"%s\" in list", 495 method); 496 goto out; 497 } 498 } 499 ret = 0; 500 out: 501 free(omethods); 502 return ret; 503 } 504 505 /* 506 * Prune the AuthenticationMethods supplied in the configuration, removing 507 * any methods lists that include disabled methods. Note that this might 508 * leave authctxt->num_auth_methods == 0, even when multiple required auth 509 * has been requested. For this reason, all tests for whether multiple is 510 * enabled should consult options.num_auth_methods directly. 511 */ 512 int 513 auth2_setup_methods_lists(Authctxt *authctxt) 514 { 515 u_int i; 516 517 if (options.num_auth_methods == 0) 518 return 0; 519 debug3("%s: checking methods", __func__); 520 authctxt->auth_methods = xcalloc(options.num_auth_methods, 521 sizeof(*authctxt->auth_methods)); 522 authctxt->num_auth_methods = 0; 523 for (i = 0; i < options.num_auth_methods; i++) { 524 if (auth2_methods_valid(options.auth_methods[i], 1) != 0) { 525 logit("Authentication methods list \"%s\" contains " 526 "disabled method, skipping", 527 options.auth_methods[i]); 528 continue; 529 } 530 debug("authentication methods list %d: %s", 531 authctxt->num_auth_methods, options.auth_methods[i]); 532 authctxt->auth_methods[authctxt->num_auth_methods++] = 533 xstrdup(options.auth_methods[i]); 534 } 535 if (authctxt->num_auth_methods == 0) { 536 error("No AuthenticationMethods left after eliminating " 537 "disabled methods"); 538 return -1; 539 } 540 return 0; 541 } 542 543 static int 544 list_starts_with(const char *methods, const char *method, 545 const char *submethod) 546 { 547 size_t l = strlen(method); 548 int match; 549 const char *p; 550 551 if (strncmp(methods, method, l) != 0) 552 return MATCH_NONE; 553 p = methods + l; 554 match = MATCH_METHOD; 555 if (*p == ':') { 556 if (!submethod) 557 return MATCH_PARTIAL; 558 l = strlen(submethod); 559 p += 1; 560 if (strncmp(submethod, p, l)) 561 return MATCH_NONE; 562 p += l; 563 match = MATCH_BOTH; 564 } 565 if (*p != ',' && *p != '\0') 566 return MATCH_NONE; 567 return match; 568 } 569 570 /* 571 * Remove method from the start of a comma-separated list of methods. 572 * Returns 0 if the list of methods did not start with that method or 1 573 * if it did. 574 */ 575 static int 576 remove_method(char **methods, const char *method, const char *submethod) 577 { 578 char *omethods = *methods, *p; 579 size_t l = strlen(method); 580 int match; 581 582 match = list_starts_with(omethods, method, submethod); 583 if (match != MATCH_METHOD && match != MATCH_BOTH) 584 return 0; 585 p = omethods + l; 586 if (submethod && match == MATCH_BOTH) 587 p += 1 + strlen(submethod); /* include colon */ 588 if (*p == ',') 589 p++; 590 *methods = xstrdup(p); 591 free(omethods); 592 return 1; 593 } 594 595 /* 596 * Called after successful authentication. Will remove the successful method 597 * from the start of each list in which it occurs. If it was the last method 598 * in any list, then authentication is deemed successful. 599 * Returns 1 if the method completed any authentication list or 0 otherwise. 600 */ 601 int 602 auth2_update_methods_lists(Authctxt *authctxt, const char *method, 603 const char *submethod) 604 { 605 u_int i, found = 0; 606 607 debug3("%s: updating methods list after \"%s\"", __func__, method); 608 for (i = 0; i < authctxt->num_auth_methods; i++) { 609 if (!remove_method(&(authctxt->auth_methods[i]), method, 610 submethod)) 611 continue; 612 found = 1; 613 if (*authctxt->auth_methods[i] == '\0') { 614 debug2("authentication methods list %d complete", i); 615 return 1; 616 } 617 debug3("authentication methods list %d remaining: \"%s\"", 618 i, authctxt->auth_methods[i]); 619 } 620 /* This should not happen, but would be bad if it did */ 621 if (!found) 622 fatal("%s: method not in AuthenticationMethods", __func__); 623 return 0; 624 } 625 626 /* Reset method-specific information */ 627 void auth2_authctxt_reset_info(Authctxt *authctxt) 628 { 629 sshkey_free(authctxt->auth_method_key); 630 free(authctxt->auth_method_info); 631 authctxt->auth_method_key = NULL; 632 authctxt->auth_method_info = NULL; 633 } 634 635 /* Record auth method-specific information for logs */ 636 void 637 auth2_record_info(Authctxt *authctxt, const char *fmt, ...) 638 { 639 va_list ap; 640 int i; 641 642 free(authctxt->auth_method_info); 643 authctxt->auth_method_info = NULL; 644 645 va_start(ap, fmt); 646 i = vasprintf(&authctxt->auth_method_info, fmt, ap); 647 va_end(ap); 648 649 if (i < 0 || authctxt->auth_method_info == NULL) 650 fatal("%s: vasprintf failed", __func__); 651 } 652 653 /* 654 * Records a public key used in authentication. This is used for logging 655 * and to ensure that the same key is not subsequently accepted again for 656 * multiple authentication. 657 */ 658 void 659 auth2_record_key(Authctxt *authctxt, int authenticated, 660 const struct sshkey *key) 661 { 662 struct sshkey **tmp, *dup; 663 int r; 664 665 if ((r = sshkey_from_private(key, &dup)) != 0) 666 fatal("%s: copy key: %s", __func__, ssh_err(r)); 667 sshkey_free(authctxt->auth_method_key); 668 authctxt->auth_method_key = dup; 669 670 if (!authenticated) 671 return; 672 673 /* If authenticated, make sure we don't accept this key again */ 674 if ((r = sshkey_from_private(key, &dup)) != 0) 675 fatal("%s: copy key: %s", __func__, ssh_err(r)); 676 if (authctxt->nprev_keys >= INT_MAX || 677 (tmp = recallocarray(authctxt->prev_keys, authctxt->nprev_keys, 678 authctxt->nprev_keys + 1, sizeof(*authctxt->prev_keys))) == NULL) 679 fatal("%s: reallocarray failed", __func__); 680 authctxt->prev_keys = tmp; 681 authctxt->prev_keys[authctxt->nprev_keys] = dup; 682 authctxt->nprev_keys++; 683 684 } 685 686 /* Checks whether a key has already been previously used for authentication */ 687 int 688 auth2_key_already_used(Authctxt *authctxt, const struct sshkey *key) 689 { 690 u_int i; 691 char *fp; 692 693 for (i = 0; i < authctxt->nprev_keys; i++) { 694 if (sshkey_equal_public(key, authctxt->prev_keys[i])) { 695 fp = sshkey_fingerprint(authctxt->prev_keys[i], 696 options.fingerprint_hash, SSH_FP_DEFAULT); 697 debug3("%s: key already used: %s %s", __func__, 698 sshkey_type(authctxt->prev_keys[i]), 699 fp == NULL ? "UNKNOWN" : fp); 700 free(fp); 701 return 1; 702 } 703 } 704 return 0; 705 } 706 707 /* 708 * Updates authctxt->session_info with details of authentication. Should be 709 * whenever an authentication method succeeds. 710 */ 711 void 712 auth2_update_session_info(Authctxt *authctxt, const char *method, 713 const char *submethod) 714 { 715 int r; 716 717 if (authctxt->session_info == NULL) { 718 if ((authctxt->session_info = sshbuf_new()) == NULL) 719 fatal("%s: sshbuf_new", __func__); 720 } 721 722 /* Append method[/submethod] */ 723 if ((r = sshbuf_putf(authctxt->session_info, "%s%s%s", 724 method, submethod == NULL ? "" : "/", 725 submethod == NULL ? "" : submethod)) != 0) 726 fatal("%s: append method: %s", __func__, ssh_err(r)); 727 728 /* Append key if present */ 729 if (authctxt->auth_method_key != NULL) { 730 if ((r = sshbuf_put_u8(authctxt->session_info, ' ')) != 0 || 731 (r = sshkey_format_text(authctxt->auth_method_key, 732 authctxt->session_info)) != 0) 733 fatal("%s: append key: %s", __func__, ssh_err(r)); 734 } 735 736 if (authctxt->auth_method_info != NULL) { 737 /* Ensure no ambiguity here */ 738 if (strchr(authctxt->auth_method_info, '\n') != NULL) 739 fatal("%s: auth_method_info contains \\n", __func__); 740 if ((r = sshbuf_put_u8(authctxt->session_info, ' ')) != 0 || 741 (r = sshbuf_putf(authctxt->session_info, "%s", 742 authctxt->auth_method_info)) != 0) { 743 fatal("%s: append method info: %s", 744 __func__, ssh_err(r)); 745 } 746 } 747 if ((r = sshbuf_put_u8(authctxt->session_info, '\n')) != 0) 748 fatal("%s: append: %s", __func__, ssh_err(r)); 749 } 750 751