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