1 /* $OpenBSD: auth.c,v 1.113 2015/08/21 03:42:19 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
31 #include <netinet/in.h>
32
33 #include <errno.h>
34 #include <fcntl.h>
35 #ifdef HAVE_PATHS_H
36 # include <paths.h>
37 #endif
38 #include <pwd.h>
39 #ifdef HAVE_LOGIN_H
40 #include <login.h>
41 #endif
42 #ifdef USE_SHADOW
43 #include <shadow.h>
44 #endif
45 #ifdef HAVE_LIBGEN_H
46 #include <libgen.h>
47 #endif
48 #include <stdarg.h>
49 #include <stdio.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <limits.h>
53
54 #include "xmalloc.h"
55 #include "match.h"
56 #include "groupaccess.h"
57 #include "log.h"
58 #include "buffer.h"
59 #include "misc.h"
60 #include "servconf.h"
61 #include "key.h"
62 #include "hostfile.h"
63 #include "auth.h"
64 #include "auth-options.h"
65 #include "canohost.h"
66 #include "uidswap.h"
67 #include "packet.h"
68 #include "loginrec.h"
69 #ifdef GSSAPI
70 #include "ssh-gss.h"
71 #endif
72 #include "authfile.h"
73 #include "monitor_wrap.h"
74 #include "authfile.h"
75 #include "ssherr.h"
76 #include "compat.h"
77
78 /* import */
79 extern ServerOptions options;
80 extern int use_privsep;
81 extern Buffer loginmsg;
82 extern struct passwd *privsep_pw;
83
84 /* Debugging messages */
85 Buffer auth_debug;
86 int auth_debug_init;
87
88 /*
89 * Check if the user is allowed to log in via ssh. If user is listed
90 * in DenyUsers or one of user's groups is listed in DenyGroups, false
91 * will be returned. If AllowUsers isn't empty and user isn't listed
92 * there, or if AllowGroups isn't empty and one of user's groups isn't
93 * listed there, false will be returned.
94 * If the user's shell is not executable, false will be returned.
95 * Otherwise true is returned.
96 */
97 int
allowed_user(struct passwd * pw)98 allowed_user(struct passwd * pw)
99 {
100 struct stat st;
101 const char *hostname = NULL, *ipaddr = NULL, *passwd = NULL;
102 u_int i;
103 #ifdef USE_SHADOW
104 struct spwd *spw = NULL;
105 #endif
106
107 /* Shouldn't be called if pw is NULL, but better safe than sorry... */
108 if (!pw || !pw->pw_name)
109 return 0;
110
111 #ifdef USE_SHADOW
112 if (!options.use_pam)
113 spw = getspnam(pw->pw_name);
114 #ifdef HAS_SHADOW_EXPIRE
115 if (!options.use_pam && spw != NULL && auth_shadow_acctexpired(spw))
116 return 0;
117 #endif /* HAS_SHADOW_EXPIRE */
118 #endif /* USE_SHADOW */
119
120 /* grab passwd field for locked account check */
121 passwd = pw->pw_passwd;
122 #ifdef USE_SHADOW
123 if (spw != NULL)
124 #ifdef USE_LIBIAF
125 passwd = get_iaf_password(pw);
126 #else
127 passwd = spw->sp_pwdp;
128 #endif /* USE_LIBIAF */
129 #endif
130
131 /* check for locked account */
132 if (!options.use_pam && passwd && *passwd) {
133 int locked = 0;
134
135 #ifdef LOCKED_PASSWD_STRING
136 if (strcmp(passwd, LOCKED_PASSWD_STRING) == 0)
137 locked = 1;
138 #endif
139 #ifdef LOCKED_PASSWD_PREFIX
140 if (strncmp(passwd, LOCKED_PASSWD_PREFIX,
141 strlen(LOCKED_PASSWD_PREFIX)) == 0)
142 locked = 1;
143 #endif
144 #ifdef LOCKED_PASSWD_SUBSTR
145 if (strstr(passwd, LOCKED_PASSWD_SUBSTR))
146 locked = 1;
147 #endif
148 #ifdef USE_LIBIAF
149 free((void *) passwd);
150 #endif /* USE_LIBIAF */
151 if (locked) {
152 logit("User %.100s not allowed because account is locked",
153 pw->pw_name);
154 return 0;
155 }
156 }
157
158 /*
159 * Deny if shell does not exist or is not executable unless we
160 * are chrooting.
161 */
162 if (options.chroot_directory == NULL ||
163 strcasecmp(options.chroot_directory, "none") == 0) {
164 char *shell = xstrdup((pw->pw_shell[0] == '\0') ?
165 _PATH_BSHELL : pw->pw_shell); /* empty = /bin/sh */
166
167 if (stat(shell, &st) != 0) {
168 logit("User %.100s not allowed because shell %.100s "
169 "does not exist", pw->pw_name, shell);
170 free(shell);
171 return 0;
172 }
173 if (S_ISREG(st.st_mode) == 0 ||
174 (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) {
175 logit("User %.100s not allowed because shell %.100s "
176 "is not executable", pw->pw_name, shell);
177 free(shell);
178 return 0;
179 }
180 free(shell);
181 }
182
183 if (options.num_deny_users > 0 || options.num_allow_users > 0 ||
184 options.num_deny_groups > 0 || options.num_allow_groups > 0) {
185 hostname = get_canonical_hostname(options.use_dns);
186 ipaddr = get_remote_ipaddr();
187 }
188
189 /* Return false if user is listed in DenyUsers */
190 if (options.num_deny_users > 0) {
191 for (i = 0; i < options.num_deny_users; i++)
192 if (match_user(pw->pw_name, hostname, ipaddr,
193 options.deny_users[i])) {
194 logit("User %.100s from %.100s not allowed "
195 "because listed in DenyUsers",
196 pw->pw_name, hostname);
197 return 0;
198 }
199 }
200 /* Return false if AllowUsers isn't empty and user isn't listed there */
201 if (options.num_allow_users > 0) {
202 for (i = 0; i < options.num_allow_users; i++)
203 if (match_user(pw->pw_name, hostname, ipaddr,
204 options.allow_users[i]))
205 break;
206 /* i < options.num_allow_users iff we break for loop */
207 if (i >= options.num_allow_users) {
208 logit("User %.100s from %.100s not allowed because "
209 "not listed in AllowUsers", pw->pw_name, hostname);
210 return 0;
211 }
212 }
213 if (options.num_deny_groups > 0 || options.num_allow_groups > 0) {
214 /* Get the user's group access list (primary and supplementary) */
215 if (ga_init(pw->pw_name, pw->pw_gid) == 0) {
216 logit("User %.100s from %.100s not allowed because "
217 "not in any group", pw->pw_name, hostname);
218 return 0;
219 }
220
221 /* Return false if one of user's groups is listed in DenyGroups */
222 if (options.num_deny_groups > 0)
223 if (ga_match(options.deny_groups,
224 options.num_deny_groups)) {
225 ga_free();
226 logit("User %.100s from %.100s not allowed "
227 "because a group is listed in DenyGroups",
228 pw->pw_name, hostname);
229 return 0;
230 }
231 /*
232 * Return false if AllowGroups isn't empty and one of user's groups
233 * isn't listed there
234 */
235 if (options.num_allow_groups > 0)
236 if (!ga_match(options.allow_groups,
237 options.num_allow_groups)) {
238 ga_free();
239 logit("User %.100s from %.100s not allowed "
240 "because none of user's groups are listed "
241 "in AllowGroups", pw->pw_name, hostname);
242 return 0;
243 }
244 ga_free();
245 }
246
247 #ifdef CUSTOM_SYS_AUTH_ALLOWED_USER
248 if (!sys_auth_allowed_user(pw, &loginmsg))
249 return 0;
250 #endif
251
252 /* We found no reason not to let this user try to log on... */
253 return 1;
254 }
255
256 void
auth_info(Authctxt * authctxt,const char * fmt,...)257 auth_info(Authctxt *authctxt, const char *fmt, ...)
258 {
259 va_list ap;
260 int i;
261
262 free(authctxt->info);
263 authctxt->info = NULL;
264
265 va_start(ap, fmt);
266 i = vasprintf(&authctxt->info, fmt, ap);
267 va_end(ap);
268
269 if (i < 0 || authctxt->info == NULL)
270 fatal("vasprintf failed");
271 }
272
273 void
auth_log(Authctxt * authctxt,int authenticated,int partial,const char * method,const char * submethod)274 auth_log(Authctxt *authctxt, int authenticated, int partial,
275 const char *method, const char *submethod)
276 {
277 void (*authlog) (const char *fmt,...) = verbose;
278 char *authmsg;
279
280 if (use_privsep && !mm_is_monitor() && !authctxt->postponed)
281 return;
282
283 /* Raise logging level */
284 if (authenticated == 1 ||
285 !authctxt->valid ||
286 authctxt->failures >= options.max_authtries / 2 ||
287 strcmp(method, "password") == 0)
288 authlog = logit;
289
290 if (authctxt->postponed)
291 authmsg = "Postponed";
292 else if (partial)
293 authmsg = "Partial";
294 else
295 authmsg = authenticated ? "Accepted" : "Failed";
296
297 authlog("%s %s%s%s for %s%.100s from %.200s port %d %s%s%s",
298 authmsg,
299 method,
300 submethod != NULL ? "/" : "", submethod == NULL ? "" : submethod,
301 authctxt->valid ? "" : "invalid user ",
302 authctxt->user,
303 get_remote_ipaddr(),
304 get_remote_port(),
305 compat20 ? "ssh2" : "ssh1",
306 authctxt->info != NULL ? ": " : "",
307 authctxt->info != NULL ? authctxt->info : "");
308 free(authctxt->info);
309 authctxt->info = NULL;
310
311 #ifdef CUSTOM_FAILED_LOGIN
312 if (authenticated == 0 && !authctxt->postponed &&
313 (strcmp(method, "password") == 0 ||
314 strncmp(method, "keyboard-interactive", 20) == 0 ||
315 strcmp(method, "challenge-response") == 0))
316 record_failed_login(authctxt->user,
317 get_canonical_hostname(options.use_dns), "ssh");
318 # ifdef WITH_AIXAUTHENTICATE
319 if (authenticated)
320 sys_auth_record_login(authctxt->user,
321 get_canonical_hostname(options.use_dns), "ssh", &loginmsg);
322 # endif
323 #endif
324 #ifdef SSH_AUDIT_EVENTS
325 if (authenticated == 0 && !authctxt->postponed)
326 audit_event(audit_classify_auth(method));
327 #endif
328 }
329
330
331 void
auth_maxtries_exceeded(Authctxt * authctxt)332 auth_maxtries_exceeded(Authctxt *authctxt)
333 {
334 error("maximum authentication attempts exceeded for "
335 "%s%.100s from %.200s port %d %s",
336 authctxt->valid ? "" : "invalid user ",
337 authctxt->user,
338 get_remote_ipaddr(),
339 get_remote_port(),
340 compat20 ? "ssh2" : "ssh1");
341 packet_disconnect("Too many authentication failures");
342 /* NOTREACHED */
343 }
344
345 /*
346 * Check whether root logins are disallowed.
347 */
348 int
auth_root_allowed(const char * method)349 auth_root_allowed(const char *method)
350 {
351 switch (options.permit_root_login) {
352 case PERMIT_YES:
353 return 1;
354 case PERMIT_NO_PASSWD:
355 if (strcmp(method, "publickey") == 0 ||
356 strcmp(method, "hostbased") == 0 ||
357 strcmp(method, "gssapi-with-mic") == 0)
358 return 1;
359 break;
360 case PERMIT_FORCED_ONLY:
361 if (forced_command) {
362 logit("Root login accepted for forced command.");
363 return 1;
364 }
365 break;
366 }
367 logit("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr());
368 return 0;
369 }
370
371
372 /*
373 * Given a template and a passwd structure, build a filename
374 * by substituting % tokenised options. Currently, %% becomes '%',
375 * %h becomes the home directory and %u the username.
376 *
377 * This returns a buffer allocated by xmalloc.
378 */
379 char *
expand_authorized_keys(const char * filename,struct passwd * pw)380 expand_authorized_keys(const char *filename, struct passwd *pw)
381 {
382 char *file, ret[PATH_MAX];
383 int i;
384
385 file = percent_expand(filename, "h", pw->pw_dir,
386 "u", pw->pw_name, (char *)NULL);
387
388 /*
389 * Ensure that filename starts anchored. If not, be backward
390 * compatible and prepend the '%h/'
391 */
392 if (*file == '/')
393 return (file);
394
395 i = snprintf(ret, sizeof(ret), "%s/%s", pw->pw_dir, file);
396 if (i < 0 || (size_t)i >= sizeof(ret))
397 fatal("expand_authorized_keys: path too long");
398 free(file);
399 return (xstrdup(ret));
400 }
401
402 char *
authorized_principals_file(struct passwd * pw)403 authorized_principals_file(struct passwd *pw)
404 {
405 if (options.authorized_principals_file == NULL)
406 return NULL;
407 return expand_authorized_keys(options.authorized_principals_file, pw);
408 }
409
410 /* return ok if key exists in sysfile or userfile */
411 HostStatus
check_key_in_hostfiles(struct passwd * pw,Key * key,const char * host,const char * sysfile,const char * userfile)412 check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host,
413 const char *sysfile, const char *userfile)
414 {
415 char *user_hostfile;
416 struct stat st;
417 HostStatus host_status;
418 struct hostkeys *hostkeys;
419 const struct hostkey_entry *found;
420
421 hostkeys = init_hostkeys();
422 load_hostkeys(hostkeys, host, sysfile);
423 if (userfile != NULL) {
424 user_hostfile = tilde_expand_filename(userfile, pw->pw_uid);
425 if (options.strict_modes &&
426 (stat(user_hostfile, &st) == 0) &&
427 ((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
428 (st.st_mode & 022) != 0)) {
429 logit("Authentication refused for %.100s: "
430 "bad owner or modes for %.200s",
431 pw->pw_name, user_hostfile);
432 auth_debug_add("Ignored %.200s: bad ownership or modes",
433 user_hostfile);
434 } else {
435 temporarily_use_uid(pw);
436 load_hostkeys(hostkeys, host, user_hostfile);
437 restore_uid();
438 }
439 free(user_hostfile);
440 }
441 host_status = check_key_in_hostkeys(hostkeys, key, &found);
442 if (host_status == HOST_REVOKED)
443 error("WARNING: revoked key for %s attempted authentication",
444 found->host);
445 else if (host_status == HOST_OK)
446 debug("%s: key for %s found at %s:%ld", __func__,
447 found->host, found->file, found->line);
448 else
449 debug("%s: key for host %s not found", __func__, host);
450
451 free_hostkeys(hostkeys);
452
453 return host_status;
454 }
455
456 /*
457 * Check a given path for security. This is defined as all components
458 * of the path to the file must be owned by either the owner of
459 * of the file or root and no directories must be group or world writable.
460 *
461 * XXX Should any specific check be done for sym links ?
462 *
463 * Takes a file name, its stat information (preferably from fstat() to
464 * avoid races), the uid of the expected owner, their home directory and an
465 * error buffer plus max size as arguments.
466 *
467 * Returns 0 on success and -1 on failure
468 */
469 int
auth_secure_path(const char * name,struct stat * stp,const char * pw_dir,uid_t uid,char * err,size_t errlen)470 auth_secure_path(const char *name, struct stat *stp, const char *pw_dir,
471 uid_t uid, char *err, size_t errlen)
472 {
473 char buf[PATH_MAX], homedir[PATH_MAX];
474 char *cp;
475 int comparehome = 0;
476 struct stat st;
477
478 if (realpath(name, buf) == NULL) {
479 snprintf(err, errlen, "realpath %s failed: %s", name,
480 strerror(errno));
481 return -1;
482 }
483 if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL)
484 comparehome = 1;
485
486 if (!S_ISREG(stp->st_mode)) {
487 snprintf(err, errlen, "%s is not a regular file", buf);
488 return -1;
489 }
490 if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) ||
491 (stp->st_mode & 022) != 0) {
492 #if defined(ANDROID)
493 /* needed to allow root login on Android. */
494 if (getuid() != 0)
495 #endif
496 {
497 snprintf(err, errlen, "bad ownership or modes for file %s",
498 buf);
499 return -1;
500 }
501 }
502
503 /* for each component of the canonical path, walking upwards */
504 for (;;) {
505 if ((cp = dirname(buf)) == NULL) {
506 snprintf(err, errlen, "dirname() failed");
507 return -1;
508 }
509 strlcpy(buf, cp, sizeof(buf));
510
511 #if !defined(ANDROID)
512 /* /data is owned by system user, which causes this check to fail */
513 if (stat(buf, &st) < 0 ||
514 (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) ||
515 (st.st_mode & 022) != 0) {
516 snprintf(err, errlen,
517 "bad ownership or modes for directory %s", buf);
518 return -1;
519 }
520 #endif
521
522 /* If are past the homedir then we can stop */
523 if (comparehome && strcmp(homedir, buf) == 0)
524 break;
525
526 /*
527 * dirname should always complete with a "/" path,
528 * but we can be paranoid and check for "." too
529 */
530 if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0))
531 break;
532 }
533 return 0;
534 }
535
536 /*
537 * Version of secure_path() that accepts an open file descriptor to
538 * avoid races.
539 *
540 * Returns 0 on success and -1 on failure
541 */
542 static int
secure_filename(FILE * f,const char * file,struct passwd * pw,char * err,size_t errlen)543 secure_filename(FILE *f, const char *file, struct passwd *pw,
544 char *err, size_t errlen)
545 {
546 struct stat st;
547
548 /* check the open file to avoid races */
549 if (fstat(fileno(f), &st) < 0) {
550 snprintf(err, errlen, "cannot stat file %s: %s",
551 file, strerror(errno));
552 return -1;
553 }
554 return auth_secure_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen);
555 }
556
557 static FILE *
auth_openfile(const char * file,struct passwd * pw,int strict_modes,int log_missing,char * file_type)558 auth_openfile(const char *file, struct passwd *pw, int strict_modes,
559 int log_missing, char *file_type)
560 {
561 char line[1024];
562 struct stat st;
563 int fd;
564 FILE *f;
565
566 if ((fd = open(file, O_RDONLY|O_NONBLOCK)) == -1) {
567 if (log_missing || errno != ENOENT)
568 debug("Could not open %s '%s': %s", file_type, file,
569 strerror(errno));
570 return NULL;
571 }
572
573 if (fstat(fd, &st) < 0) {
574 close(fd);
575 return NULL;
576 }
577 if (!S_ISREG(st.st_mode)) {
578 logit("User %s %s %s is not a regular file",
579 pw->pw_name, file_type, file);
580 close(fd);
581 return NULL;
582 }
583 unset_nonblock(fd);
584 if ((f = fdopen(fd, "r")) == NULL) {
585 close(fd);
586 return NULL;
587 }
588 if (strict_modes &&
589 secure_filename(f, file, pw, line, sizeof(line)) != 0) {
590 fclose(f);
591 logit("Authentication refused: %s", line);
592 auth_debug_add("Ignored %s: %s", file_type, line);
593 return NULL;
594 }
595
596 return f;
597 }
598
599
600 FILE *
auth_openkeyfile(const char * file,struct passwd * pw,int strict_modes)601 auth_openkeyfile(const char *file, struct passwd *pw, int strict_modes)
602 {
603 return auth_openfile(file, pw, strict_modes, 1, "authorized keys");
604 }
605
606 FILE *
auth_openprincipals(const char * file,struct passwd * pw,int strict_modes)607 auth_openprincipals(const char *file, struct passwd *pw, int strict_modes)
608 {
609 return auth_openfile(file, pw, strict_modes, 0,
610 "authorized principals");
611 }
612
613 struct passwd *
getpwnamallow(const char * user)614 getpwnamallow(const char *user)
615 {
616 #ifdef HAVE_LOGIN_CAP
617 extern login_cap_t *lc;
618 #ifdef BSD_AUTH
619 auth_session_t *as;
620 #endif
621 #endif
622 struct passwd *pw;
623 struct connection_info *ci = get_connection_info(1, options.use_dns);
624
625 ci->user = user;
626 parse_server_match_config(&options, ci);
627
628 #if defined(_AIX) && defined(HAVE_SETAUTHDB)
629 aix_setauthdb(user);
630 #endif
631
632 #if defined(ANDROID)
633 // Android has a fixed set of users. Any incoming user that we can't
634 // identify should be authenticated as the shell user.
635 if (strcmp(user, "root") && strcmp(user, "shell")) {
636 logit("Login name %.100s forced to shell", user);
637 user = "shell";
638 }
639 #endif
640 pw = getpwnam(user);
641
642 #if defined(_AIX) && defined(HAVE_SETAUTHDB)
643 aix_restoreauthdb();
644 #endif
645 #ifdef HAVE_CYGWIN
646 /*
647 * Windows usernames are case-insensitive. To avoid later problems
648 * when trying to match the username, the user is only allowed to
649 * login if the username is given in the same case as stored in the
650 * user database.
651 */
652 if (pw != NULL && strcmp(user, pw->pw_name) != 0) {
653 logit("Login name %.100s does not match stored username %.100s",
654 user, pw->pw_name);
655 pw = NULL;
656 }
657 #endif
658 if (pw == NULL) {
659 logit("Invalid user %.100s from %.100s",
660 user, get_remote_ipaddr());
661 #ifdef CUSTOM_FAILED_LOGIN
662 record_failed_login(user,
663 get_canonical_hostname(options.use_dns), "ssh");
664 #endif
665 #ifdef SSH_AUDIT_EVENTS
666 audit_event(SSH_INVALID_USER);
667 #endif /* SSH_AUDIT_EVENTS */
668 return (NULL);
669 }
670 if (!allowed_user(pw))
671 return (NULL);
672 #ifdef HAVE_LOGIN_CAP
673 if ((lc = login_getclass(pw->pw_class)) == NULL) {
674 debug("unable to get login class: %s", user);
675 return (NULL);
676 }
677 #ifdef BSD_AUTH
678 if ((as = auth_open()) == NULL || auth_setpwd(as, pw) != 0 ||
679 auth_approval(as, lc, pw->pw_name, "ssh") <= 0) {
680 debug("Approval failure for %s", user);
681 pw = NULL;
682 }
683 if (as != NULL)
684 auth_close(as);
685 #endif
686 #endif
687 if (pw != NULL)
688 return (pwcopy(pw));
689 return (NULL);
690 }
691
692 /* Returns 1 if key is revoked by revoked_keys_file, 0 otherwise */
693 int
auth_key_is_revoked(Key * key)694 auth_key_is_revoked(Key *key)
695 {
696 char *fp = NULL;
697 int r;
698
699 if (options.revoked_keys_file == NULL)
700 return 0;
701 if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
702 SSH_FP_DEFAULT)) == NULL) {
703 r = SSH_ERR_ALLOC_FAIL;
704 error("%s: fingerprint key: %s", __func__, ssh_err(r));
705 goto out;
706 }
707
708 r = sshkey_check_revoked(key, options.revoked_keys_file);
709 switch (r) {
710 case 0:
711 break; /* not revoked */
712 case SSH_ERR_KEY_REVOKED:
713 error("Authentication key %s %s revoked by file %s",
714 sshkey_type(key), fp, options.revoked_keys_file);
715 goto out;
716 default:
717 error("Error checking authentication key %s %s in "
718 "revoked keys file %s: %s", sshkey_type(key), fp,
719 options.revoked_keys_file, ssh_err(r));
720 goto out;
721 }
722
723 /* Success */
724 r = 0;
725
726 out:
727 free(fp);
728 return r == 0 ? 0 : 1;
729 }
730
731 void
auth_debug_add(const char * fmt,...)732 auth_debug_add(const char *fmt,...)
733 {
734 char buf[1024];
735 va_list args;
736
737 if (!auth_debug_init)
738 return;
739
740 va_start(args, fmt);
741 vsnprintf(buf, sizeof(buf), fmt, args);
742 va_end(args);
743 buffer_put_cstring(&auth_debug, buf);
744 }
745
746 void
auth_debug_send(void)747 auth_debug_send(void)
748 {
749 char *msg;
750
751 if (!auth_debug_init)
752 return;
753 while (buffer_len(&auth_debug)) {
754 msg = buffer_get_string(&auth_debug, NULL);
755 packet_send_debug("%s", msg);
756 free(msg);
757 }
758 }
759
760 void
auth_debug_reset(void)761 auth_debug_reset(void)
762 {
763 if (auth_debug_init)
764 buffer_clear(&auth_debug);
765 else {
766 buffer_init(&auth_debug);
767 auth_debug_init = 1;
768 }
769 }
770
771 struct passwd *
fakepw(void)772 fakepw(void)
773 {
774 static struct passwd fake;
775
776 memset(&fake, 0, sizeof(fake));
777 fake.pw_name = "NOUSER";
778 fake.pw_passwd =
779 "$2a$06$r3.juUaHZDlIbQaO2dS9FuYxL1W9M81R1Tc92PoSNmzvpEqLkLGrK";
780 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
781 fake.pw_gecos = "NOUSER";
782 #endif
783 fake.pw_uid = privsep_pw == NULL ? (uid_t)-1 : privsep_pw->pw_uid;
784 fake.pw_gid = privsep_pw == NULL ? (gid_t)-1 : privsep_pw->pw_gid;
785 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
786 fake.pw_class = "";
787 #endif
788 fake.pw_dir = "/nonexist";
789 fake.pw_shell = "/nonexist";
790
791 return (&fake);
792 }
793