Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 1 | /* |
Ben Lindstrom | 92a2e38 | 2001-03-05 06:59:27 +0000 | [diff] [blame] | 2 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions |
| 6 | * are met: |
| 7 | * 1. Redistributions of source code must retain the above copyright |
| 8 | * notice, this list of conditions and the following disclaimer. |
| 9 | * 2. Redistributions in binary form must reproduce the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer in the |
| 11 | * documentation and/or other materials provided with the distribution. |
| 12 | * |
| 13 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 14 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 15 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 16 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 17 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 18 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 19 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 20 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 21 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 22 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 23 | */ |
| 24 | |
| 25 | #include "includes.h" |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 26 | RCSID("$OpenBSD: auth.c,v 1.26 2001/06/27 04:48:52 markus Exp $"); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 27 | |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 28 | #ifdef HAVE_LOGIN_H |
| 29 | #include <login.h> |
| 30 | #endif |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 31 | #if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) |
| 32 | #include <shadow.h> |
| 33 | #endif /* defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) */ |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 34 | |
Ben Lindstrom | 68c3ce1 | 2001-06-10 17:24:51 +0000 | [diff] [blame] | 35 | #ifdef HAVE_LIBGEN_H |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 36 | #include <libgen.h> |
Ben Lindstrom | 68c3ce1 | 2001-06-10 17:24:51 +0000 | [diff] [blame] | 37 | #endif |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 38 | |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 39 | #include "xmalloc.h" |
| 40 | #include "match.h" |
| 41 | #include "groupaccess.h" |
| 42 | #include "log.h" |
| 43 | #include "servconf.h" |
Damien Miller | efb4afe | 2000-04-12 18:45:05 +1000 | [diff] [blame] | 44 | #include "auth.h" |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 45 | #include "auth-options.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 46 | #include "canohost.h" |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 47 | #include "buffer.h" |
| 48 | #include "bufaux.h" |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 49 | #include "uidswap.h" |
| 50 | #include "tildexpand.h" |
Damien Miller | efb4afe | 2000-04-12 18:45:05 +1000 | [diff] [blame] | 51 | |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 52 | /* import */ |
| 53 | extern ServerOptions options; |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 54 | |
| 55 | /* |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 56 | * Check if the user is allowed to log in via ssh. If user is listed |
| 57 | * in DenyUsers or one of user's groups is listed in DenyGroups, false |
| 58 | * will be returned. If AllowUsers isn't empty and user isn't listed |
| 59 | * there, or if AllowGroups isn't empty and one of user's groups isn't |
| 60 | * listed there, false will be returned. |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 61 | * If the user's shell is not executable, false will be returned. |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 62 | * Otherwise true is returned. |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 63 | */ |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 64 | int |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 65 | allowed_user(struct passwd * pw) |
| 66 | { |
| 67 | struct stat st; |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 68 | const char *hostname = NULL, *ipaddr = NULL; |
Damien Miller | e7cf07c | 2001-03-20 09:15:57 +1100 | [diff] [blame] | 69 | char *shell; |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 70 | int i; |
| 71 | #ifdef WITH_AIXAUTHENTICATE |
| 72 | char *loginmsg; |
| 73 | #endif /* WITH_AIXAUTHENTICATE */ |
Kevin Steves | a58e0af | 2000-10-29 14:38:55 +0000 | [diff] [blame] | 74 | #if !defined(USE_PAM) && defined(HAVE_SHADOW_H) && \ |
Damien Miller | 62dd94b | 2000-09-23 14:26:32 +1100 | [diff] [blame] | 75 | !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 76 | struct spwd *spw; |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 77 | |
| 78 | /* Shouldn't be called if pw is NULL, but better safe than sorry... */ |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 79 | if (!pw || !pw->pw_name) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 80 | return 0; |
| 81 | |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 82 | spw = getspnam(pw->pw_name); |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 83 | if (spw != NULL) { |
| 84 | int days = time(NULL) / 86400; |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 85 | |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 86 | /* Check account expiry */ |
Damien Miller | 62dd94b | 2000-09-23 14:26:32 +1100 | [diff] [blame] | 87 | if ((spw->sp_expire >= 0) && (days > spw->sp_expire)) |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 88 | return 0; |
| 89 | |
| 90 | /* Check password expiry */ |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 91 | if ((spw->sp_lstchg >= 0) && (spw->sp_max >= 0) && |
Damien Miller | 606f880 | 2000-09-16 15:39:56 +1100 | [diff] [blame] | 92 | (days > (spw->sp_lstchg + spw->sp_max))) |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 93 | return 0; |
| 94 | } |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 95 | #else |
| 96 | /* Shouldn't be called if pw is NULL, but better safe than sorry... */ |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 97 | if (!pw || !pw->pw_name) |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 98 | return 0; |
| 99 | #endif |
| 100 | |
Damien Miller | ef7df54 | 2000-05-19 00:03:23 +1000 | [diff] [blame] | 101 | /* |
| 102 | * Get the shell from the password data. An empty shell field is |
| 103 | * legal, and means /bin/sh. |
| 104 | */ |
| 105 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; |
| 106 | |
| 107 | /* deny if shell does not exists or is not executable */ |
| 108 | if (stat(shell, &st) != 0) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 109 | return 0; |
| 110 | if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)))) |
| 111 | return 0; |
| 112 | |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 113 | if (options.num_deny_users > 0 || options.num_allow_users > 0) { |
| 114 | hostname = get_canonical_hostname(options.reverse_mapping_check); |
| 115 | ipaddr = get_remote_ipaddr(); |
| 116 | } |
| 117 | |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 118 | /* Return false if user is listed in DenyUsers */ |
| 119 | if (options.num_deny_users > 0) { |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 120 | for (i = 0; i < options.num_deny_users; i++) |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 121 | if (match_user(pw->pw_name, hostname, ipaddr, |
| 122 | options.deny_users[i])) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 123 | return 0; |
| 124 | } |
| 125 | /* Return false if AllowUsers isn't empty and user isn't listed there */ |
| 126 | if (options.num_allow_users > 0) { |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 127 | for (i = 0; i < options.num_allow_users; i++) |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 128 | if (match_user(pw->pw_name, hostname, ipaddr, |
| 129 | options.allow_users[i])) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 130 | break; |
| 131 | /* i < options.num_allow_users iff we break for loop */ |
| 132 | if (i >= options.num_allow_users) |
| 133 | return 0; |
| 134 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 135 | if (options.num_deny_groups > 0 || options.num_allow_groups > 0) { |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 136 | /* Get the user's group access list (primary and supplementary) */ |
| 137 | if (ga_init(pw->pw_name, pw->pw_gid) == 0) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 138 | return 0; |
| 139 | |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 140 | /* Return false if one of user's groups is listed in DenyGroups */ |
| 141 | if (options.num_deny_groups > 0) |
| 142 | if (ga_match(options.deny_groups, |
| 143 | options.num_deny_groups)) { |
| 144 | ga_free(); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 145 | return 0; |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 146 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 147 | /* |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 148 | * Return false if AllowGroups isn't empty and one of user's groups |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 149 | * isn't listed there |
| 150 | */ |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 151 | if (options.num_allow_groups > 0) |
| 152 | if (!ga_match(options.allow_groups, |
| 153 | options.num_allow_groups)) { |
| 154 | ga_free(); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 155 | return 0; |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 156 | } |
| 157 | ga_free(); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 158 | } |
| 159 | |
| 160 | #ifdef WITH_AIXAUTHENTICATE |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 161 | if (loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) { |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 162 | if (loginmsg && *loginmsg) { |
| 163 | /* Remove embedded newlines (if any) */ |
| 164 | char *p; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 165 | for (p = loginmsg; *p; p++) { |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 166 | if (*p == '\n') |
| 167 | *p = ' '; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 168 | } |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 169 | /* Remove trailing newline */ |
| 170 | *--p = '\0'; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 171 | log("Login restricted for %s: %.100s", pw->pw_name, loginmsg); |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 172 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 173 | return 0; |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 174 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 175 | #endif /* WITH_AIXAUTHENTICATE */ |
| 176 | |
| 177 | /* We found no reason not to let this user try to log on... */ |
| 178 | return 1; |
| 179 | } |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 180 | |
| 181 | Authctxt * |
| 182 | authctxt_new(void) |
| 183 | { |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 184 | Authctxt *authctxt = xmalloc(sizeof(*authctxt)); |
| 185 | memset(authctxt, 0, sizeof(*authctxt)); |
| 186 | return authctxt; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 187 | } |
| 188 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 189 | void |
| 190 | auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) |
| 191 | { |
| 192 | void (*authlog) (const char *fmt,...) = verbose; |
| 193 | char *authmsg; |
| 194 | |
| 195 | /* Raise logging level */ |
| 196 | if (authenticated == 1 || |
| 197 | !authctxt->valid || |
| 198 | authctxt->failures >= AUTH_FAIL_LOG || |
| 199 | strcmp(method, "password") == 0) |
| 200 | authlog = log; |
| 201 | |
| 202 | if (authctxt->postponed) |
| 203 | authmsg = "Postponed"; |
| 204 | else |
| 205 | authmsg = authenticated ? "Accepted" : "Failed"; |
| 206 | |
| 207 | authlog("%s %s for %s%.100s from %.200s port %d%s", |
| 208 | authmsg, |
| 209 | method, |
| 210 | authctxt->valid ? "" : "illegal user ", |
| 211 | authctxt->valid && authctxt->pw->pw_uid == 0 ? "ROOT" : authctxt->user, |
| 212 | get_remote_ipaddr(), |
| 213 | get_remote_port(), |
| 214 | info); |
| 215 | } |
| 216 | |
| 217 | /* |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 218 | * Check whether root logins are disallowed. |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 219 | */ |
| 220 | int |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 221 | auth_root_allowed(char *method) |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 222 | { |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 223 | switch (options.permit_root_login) { |
| 224 | case PERMIT_YES: |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 225 | return 1; |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 226 | break; |
| 227 | case PERMIT_NO_PASSWD: |
| 228 | if (strcmp(method, "password") != 0) |
| 229 | return 1; |
| 230 | break; |
| 231 | case PERMIT_FORCED_ONLY: |
| 232 | if (forced_command) { |
| 233 | log("Root login accepted for forced command."); |
| 234 | return 1; |
| 235 | } |
| 236 | break; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 237 | } |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 238 | log("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr()); |
| 239 | return 0; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 240 | } |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 241 | |
| 242 | |
| 243 | /* |
| 244 | * Given a template and a passwd structure, build a filename |
| 245 | * by substituting % tokenised options. Currently, %% becomes '%', |
| 246 | * %h becomes the home directory and %u the username. |
| 247 | * |
| 248 | * This returns a buffer allocated by xmalloc. |
| 249 | */ |
| 250 | char * |
| 251 | expand_filename(const char *filename, struct passwd *pw) |
| 252 | { |
| 253 | Buffer buffer; |
| 254 | char *file; |
| 255 | const char *cp; |
| 256 | |
| 257 | /* |
| 258 | * Build the filename string in the buffer by making the appropriate |
| 259 | * substitutions to the given file name. |
| 260 | */ |
| 261 | buffer_init(&buffer); |
| 262 | for (cp = filename; *cp; cp++) { |
| 263 | if (cp[0] == '%' && cp[1] == '%') { |
| 264 | buffer_append(&buffer, "%", 1); |
| 265 | cp++; |
| 266 | continue; |
| 267 | } |
| 268 | if (cp[0] == '%' && cp[1] == 'h') { |
| 269 | buffer_append(&buffer, pw->pw_dir, strlen(pw->pw_dir)); |
| 270 | cp++; |
| 271 | continue; |
| 272 | } |
| 273 | if (cp[0] == '%' && cp[1] == 'u') { |
| 274 | buffer_append(&buffer, pw->pw_name, |
| 275 | strlen(pw->pw_name)); |
| 276 | cp++; |
| 277 | continue; |
| 278 | } |
| 279 | buffer_append(&buffer, cp, 1); |
| 280 | } |
| 281 | buffer_append(&buffer, "\0", 1); |
| 282 | |
| 283 | /* |
| 284 | * Ensure that filename starts anchored. If not, be backward |
| 285 | * compatible and prepend the '%h/' |
| 286 | */ |
| 287 | file = xmalloc(MAXPATHLEN); |
| 288 | cp = buffer_ptr(&buffer); |
| 289 | if (*cp != '/') |
| 290 | snprintf(file, MAXPATHLEN, "%s/%s", pw->pw_dir, cp); |
| 291 | else |
| 292 | strlcpy(file, cp, MAXPATHLEN); |
| 293 | |
| 294 | buffer_free(&buffer); |
| 295 | return file; |
| 296 | } |
| 297 | |
| 298 | char * |
| 299 | authorized_keys_file(struct passwd *pw) |
| 300 | { |
| 301 | return expand_filename(options.authorized_keys_file, pw); |
| 302 | } |
| 303 | |
| 304 | char * |
| 305 | authorized_keys_file2(struct passwd *pw) |
| 306 | { |
| 307 | return expand_filename(options.authorized_keys_file2, pw); |
| 308 | } |
| 309 | |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 310 | /* return ok if key exists in sysfile or userfile */ |
| 311 | HostStatus |
| 312 | check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host, |
| 313 | const char *sysfile, const char *userfile) |
| 314 | { |
| 315 | Key *found; |
| 316 | char *user_hostfile; |
| 317 | struct stat st; |
| 318 | int host_status; |
| 319 | |
| 320 | /* Check if we know the host and its host key. */ |
| 321 | found = key_new(key->type); |
| 322 | host_status = check_host_in_hostfile(sysfile, host, key, found, NULL); |
| 323 | |
| 324 | if (host_status != HOST_OK && userfile != NULL) { |
| 325 | user_hostfile = tilde_expand_filename(userfile, pw->pw_uid); |
| 326 | if (options.strict_modes && |
| 327 | (stat(user_hostfile, &st) == 0) && |
| 328 | ((st.st_uid != 0 && st.st_uid != pw->pw_uid) || |
| 329 | (st.st_mode & 022) != 0)) { |
| 330 | log("Authentication refused for %.100s: " |
| 331 | "bad owner or modes for %.200s", |
| 332 | pw->pw_name, user_hostfile); |
| 333 | } else { |
| 334 | temporarily_use_uid(pw); |
| 335 | host_status = check_host_in_hostfile(user_hostfile, |
| 336 | host, key, found, NULL); |
| 337 | restore_uid(); |
| 338 | } |
| 339 | xfree(user_hostfile); |
| 340 | } |
| 341 | key_free(found); |
| 342 | |
| 343 | debug2("check_key_in_hostfiles: key %s for %s", host_status == HOST_OK ? |
| 344 | "ok" : "not found", host); |
| 345 | return host_status; |
| 346 | } |
| 347 | |
| 348 | |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 349 | /* |
| 350 | * Check a given file for security. This is defined as all components |
| 351 | * of the path to the file must either be owned by either the owner of |
Ben Lindstrom | 60567ff | 2001-06-05 20:27:53 +0000 | [diff] [blame] | 352 | * of the file or root and no directories must be group or world writable. |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 353 | * |
| 354 | * XXX Should any specific check be done for sym links ? |
| 355 | * |
| 356 | * Takes an open file descriptor, the file name, a uid and and |
| 357 | * error buffer plus max size as arguments. |
| 358 | * |
| 359 | * Returns 0 on success and -1 on failure |
| 360 | */ |
| 361 | int |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 362 | secure_filename(FILE *f, const char *file, struct passwd *pw, |
| 363 | char *err, size_t errlen) |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 364 | { |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 365 | uid_t uid = pw->pw_uid; |
| 366 | char homedir[MAXPATHLEN]; |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 367 | char buf[MAXPATHLEN]; |
| 368 | char *cp; |
| 369 | struct stat st; |
| 370 | |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 371 | strlcpy(homedir, dirname(pw->pw_dir), sizeof(homedir)); |
| 372 | |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 373 | if (realpath(file, buf) == NULL) { |
| 374 | snprintf(err, errlen, "realpath %s failed: %s", file, |
| 375 | strerror(errno)); |
| 376 | return -1; |
| 377 | } |
| 378 | |
| 379 | /* check the open file to avoid races */ |
| 380 | if (fstat(fileno(f), &st) < 0 || |
| 381 | (st.st_uid != 0 && st.st_uid != uid) || |
| 382 | (st.st_mode & 022) != 0) { |
| 383 | snprintf(err, errlen, "bad ownership or modes for file %s", |
| 384 | buf); |
| 385 | return -1; |
| 386 | } |
| 387 | |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 388 | debug3("secure_filename: terminating check at '%s'", homedir); |
| 389 | |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 390 | /* for each component of the canonical path, walking upwards */ |
| 391 | for (;;) { |
| 392 | if ((cp = dirname(buf)) == NULL) { |
| 393 | snprintf(err, errlen, "dirname() failed"); |
| 394 | return -1; |
| 395 | } |
| 396 | strlcpy(buf, cp, sizeof(buf)); |
| 397 | |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 398 | /* If are passed the homedir then we can stop */ |
| 399 | if (strcmp(buf, homedir) == 0) |
| 400 | break; |
| 401 | |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 402 | debug3("secure_filename: checking '%s'", buf); |
| 403 | if (stat(buf, &st) < 0 || |
| 404 | (st.st_uid != 0 && st.st_uid != uid) || |
| 405 | (st.st_mode & 022) != 0) { |
| 406 | snprintf(err, errlen, |
| 407 | "bad ownership or modes for directory %s", buf); |
| 408 | return -1; |
| 409 | } |
| 410 | |
| 411 | /* |
| 412 | * dirname should always complete with a "/" path, |
| 413 | * but we can be paranoid and check for "." too |
| 414 | */ |
| 415 | if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0)) |
| 416 | break; |
| 417 | } |
| 418 | return 0; |
| 419 | } |