Damien Miller | 116e6df | 2002-05-22 15:06:28 +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 | 485075e | 2002-11-09 15:45:12 +0000 | [diff] [blame] | 26 | RCSID("$OpenBSD: auth.c,v 1.46 2002/11/04 10:07:53 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" |
Ben Lindstrom | 7ebb635 | 2002-03-22 03:04:08 +0000 | [diff] [blame] | 51 | #include "misc.h" |
Ben Lindstrom | a574cda | 2002-05-15 16:16:14 +0000 | [diff] [blame] | 52 | #include "bufaux.h" |
| 53 | #include "packet.h" |
Damien Miller | efb4afe | 2000-04-12 18:45:05 +1000 | [diff] [blame] | 54 | |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 55 | /* import */ |
| 56 | extern ServerOptions options; |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 57 | |
Ben Lindstrom | a574cda | 2002-05-15 16:16:14 +0000 | [diff] [blame] | 58 | /* Debugging messages */ |
| 59 | Buffer auth_debug; |
| 60 | int auth_debug_init; |
| 61 | |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 62 | /* |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 63 | * Check if the user is allowed to log in via ssh. If user is listed |
| 64 | * in DenyUsers or one of user's groups is listed in DenyGroups, false |
| 65 | * will be returned. If AllowUsers isn't empty and user isn't listed |
| 66 | * there, or if AllowGroups isn't empty and one of user's groups isn't |
| 67 | * listed there, false will be returned. |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 68 | * If the user's shell is not executable, false will be returned. |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 69 | * Otherwise true is returned. |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 70 | */ |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 71 | int |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 72 | allowed_user(struct passwd * pw) |
| 73 | { |
| 74 | struct stat st; |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 75 | const char *hostname = NULL, *ipaddr = NULL, *passwd; |
Damien Miller | e7cf07c | 2001-03-20 09:15:57 +1100 | [diff] [blame] | 76 | char *shell; |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 77 | int i; |
| 78 | #ifdef WITH_AIXAUTHENTICATE |
| 79 | char *loginmsg; |
| 80 | #endif /* WITH_AIXAUTHENTICATE */ |
Damien Miller | 06817f9 | 2003-01-07 23:55:59 +1100 | [diff] [blame] | 81 | #if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 82 | struct spwd *spw; |
Tim Rice | 458c6bf | 2003-01-08 20:04:27 -0800 | [diff] [blame] | 83 | #if !defined(USE_PAM) && defined(HAS_SHADOW_EXPIRE) |
| 84 | time_t today; |
| 85 | #endif |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 86 | #endif |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 87 | |
| 88 | /* 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] | 89 | if (!pw || !pw->pw_name) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 90 | return 0; |
| 91 | |
Damien Miller | 06817f9 | 2003-01-07 23:55:59 +1100 | [diff] [blame] | 92 | /* Grab the password for locked account checking */ |
| 93 | #if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 94 | spw = getspnam(pw->pw_name); |
Damien Miller | 06817f9 | 2003-01-07 23:55:59 +1100 | [diff] [blame] | 95 | if (!spw) |
| 96 | return 0; |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 97 | passwd = spw->sp_pwdp; |
| 98 | #else |
| 99 | passwd = pw->pw_passwd; |
| 100 | #endif |
Damien Miller | 64004b5 | 2003-01-07 16:15:20 +1100 | [diff] [blame] | 101 | |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 102 | /* check for locked account */ |
| 103 | if (strcmp(passwd, "*LK*") == 0 || passwd[0] == '!') { |
| 104 | log("User %.100s not allowed because account is locked", |
| 105 | pw->pw_name); |
| 106 | return 0; |
| 107 | } |
| 108 | |
Damien Miller | 06817f9 | 2003-01-07 23:55:59 +1100 | [diff] [blame] | 109 | #if !defined(USE_PAM) && defined(HAVE_SHADOW_H) && \ |
| 110 | !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) |
| 111 | #define DAY (24L * 60 * 60) /* 1 day in seconds */ |
Tim Rice | 458c6bf | 2003-01-08 20:04:27 -0800 | [diff] [blame] | 112 | today = time(NULL) / DAY; |
Damien Miller | 06817f9 | 2003-01-07 23:55:59 +1100 | [diff] [blame] | 113 | debug3("allowed_user: today %d sp_expire %d sp_lstchg %d" |
| 114 | " sp_max %d", (int)today, (int)spw->sp_expire, |
| 115 | (int)spw->sp_lstchg, (int)spw->sp_max); |
| 116 | |
| 117 | /* |
| 118 | * We assume account and password expiration occurs the |
| 119 | * day after the day specified. |
| 120 | */ |
| 121 | if (spw->sp_expire != -1 && today > spw->sp_expire) { |
| 122 | log("Account %.100s has expired", pw->pw_name); |
| 123 | return 0; |
| 124 | } |
| 125 | |
| 126 | if (spw->sp_lstchg == 0) { |
| 127 | log("User %.100s password has expired (root forced)", |
| 128 | pw->pw_name); |
| 129 | return 0; |
| 130 | } |
| 131 | |
| 132 | if (spw->sp_max != -1 && |
| 133 | today > spw->sp_lstchg + spw->sp_max) { |
| 134 | log("User %.100s password has expired (password aged)", |
| 135 | pw->pw_name); |
| 136 | return 0; |
| 137 | } |
| 138 | #endif |
| 139 | |
Damien Miller | ef7df54 | 2000-05-19 00:03:23 +1000 | [diff] [blame] | 140 | /* |
| 141 | * Get the shell from the password data. An empty shell field is |
| 142 | * legal, and means /bin/sh. |
| 143 | */ |
| 144 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; |
| 145 | |
| 146 | /* deny if shell does not exists or is not executable */ |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 147 | if (stat(shell, &st) != 0) { |
| 148 | log("User %.100s not allowed because shell %.100s does not exist", |
| 149 | pw->pw_name, shell); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 150 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 151 | } |
Ben Lindstrom | b61e6df | 2002-03-22 01:15:33 +0000 | [diff] [blame] | 152 | if (S_ISREG(st.st_mode) == 0 || |
| 153 | (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) { |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 154 | log("User %.100s not allowed because shell %.100s is not executable", |
| 155 | pw->pw_name, shell); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 156 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 157 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 158 | |
Ben Lindstrom | 3fb5d00 | 2002-03-05 01:42:42 +0000 | [diff] [blame] | 159 | if (options.num_deny_users > 0 || options.num_allow_users > 0) { |
| 160 | hostname = get_canonical_hostname(options.verify_reverse_mapping); |
| 161 | ipaddr = get_remote_ipaddr(); |
| 162 | } |
| 163 | |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 164 | /* Return false if user is listed in DenyUsers */ |
| 165 | if (options.num_deny_users > 0) { |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 166 | for (i = 0; i < options.num_deny_users; i++) |
Ben Lindstrom | 6328ab3 | 2002-03-22 02:54:23 +0000 | [diff] [blame] | 167 | if (match_user(pw->pw_name, hostname, ipaddr, |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 168 | options.deny_users[i])) { |
Ben Lindstrom | 6328ab3 | 2002-03-22 02:54:23 +0000 | [diff] [blame] | 169 | log("User %.100s not allowed because listed in DenyUsers", |
| 170 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 171 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 172 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 173 | } |
| 174 | /* Return false if AllowUsers isn't empty and user isn't listed there */ |
| 175 | if (options.num_allow_users > 0) { |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 176 | for (i = 0; i < options.num_allow_users; i++) |
Ben Lindstrom | 6328ab3 | 2002-03-22 02:54:23 +0000 | [diff] [blame] | 177 | if (match_user(pw->pw_name, hostname, ipaddr, |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 178 | options.allow_users[i])) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 179 | break; |
| 180 | /* i < options.num_allow_users iff we break for loop */ |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 181 | if (i >= options.num_allow_users) { |
| 182 | log("User %.100s not allowed because not listed in AllowUsers", |
| 183 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 184 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 185 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 186 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 187 | if (options.num_deny_groups > 0 || options.num_allow_groups > 0) { |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 188 | /* Get the user's group access list (primary and supplementary) */ |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 189 | if (ga_init(pw->pw_name, pw->pw_gid) == 0) { |
| 190 | log("User %.100s not allowed because not in any group", |
| 191 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 192 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 193 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 194 | |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 195 | /* Return false if one of user's groups is listed in DenyGroups */ |
| 196 | if (options.num_deny_groups > 0) |
| 197 | if (ga_match(options.deny_groups, |
| 198 | options.num_deny_groups)) { |
| 199 | ga_free(); |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 200 | log("User %.100s not allowed because a group is listed in DenyGroups", |
| 201 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 202 | return 0; |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 203 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 204 | /* |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 205 | * 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] | 206 | * isn't listed there |
| 207 | */ |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 208 | if (options.num_allow_groups > 0) |
| 209 | if (!ga_match(options.allow_groups, |
| 210 | options.num_allow_groups)) { |
| 211 | ga_free(); |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 212 | log("User %.100s not allowed because none of user's groups are listed in AllowGroups", |
| 213 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 214 | return 0; |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 215 | } |
| 216 | ga_free(); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 217 | } |
| 218 | |
| 219 | #ifdef WITH_AIXAUTHENTICATE |
Ben Lindstrom | 97e38d8 | 2002-10-16 00:13:52 +0000 | [diff] [blame] | 220 | /* |
| 221 | * Don't check loginrestrictions() for root account (use |
| 222 | * PermitRootLogin to control logins via ssh), or if running as |
| 223 | * non-root user (since loginrestrictions will always fail). |
| 224 | */ |
| 225 | if ( (pw->pw_uid != 0) && (geteuid() == 0) && |
| 226 | loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) { |
Damien Miller | f25c18d | 2003-01-07 17:38:58 +1100 | [diff] [blame] | 227 | int loginrestrict_errno = errno; |
| 228 | |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 229 | if (loginmsg && *loginmsg) { |
| 230 | /* Remove embedded newlines (if any) */ |
| 231 | char *p; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 232 | for (p = loginmsg; *p; p++) { |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 233 | if (*p == '\n') |
| 234 | *p = ' '; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 235 | } |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 236 | /* Remove trailing newline */ |
| 237 | *--p = '\0'; |
Damien Miller | f25c18d | 2003-01-07 17:38:58 +1100 | [diff] [blame] | 238 | log("Login restricted for %s: %.100s", pw->pw_name, |
| 239 | loginmsg); |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 240 | } |
Damien Miller | f25c18d | 2003-01-07 17:38:58 +1100 | [diff] [blame] | 241 | /* Don't fail if /etc/nologin set */ |
| 242 | if (!(loginrestrict_errno == EPERM && |
| 243 | stat(_PATH_NOLOGIN, &st) == 0)) |
| 244 | return 0; |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 245 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 246 | #endif /* WITH_AIXAUTHENTICATE */ |
| 247 | |
| 248 | /* We found no reason not to let this user try to log on... */ |
| 249 | return 1; |
| 250 | } |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 251 | |
| 252 | Authctxt * |
| 253 | authctxt_new(void) |
| 254 | { |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 255 | Authctxt *authctxt = xmalloc(sizeof(*authctxt)); |
| 256 | memset(authctxt, 0, sizeof(*authctxt)); |
| 257 | return authctxt; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 258 | } |
| 259 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 260 | void |
| 261 | auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) |
| 262 | { |
| 263 | void (*authlog) (const char *fmt,...) = verbose; |
| 264 | char *authmsg; |
| 265 | |
| 266 | /* Raise logging level */ |
| 267 | if (authenticated == 1 || |
| 268 | !authctxt->valid || |
| 269 | authctxt->failures >= AUTH_FAIL_LOG || |
| 270 | strcmp(method, "password") == 0) |
| 271 | authlog = log; |
| 272 | |
| 273 | if (authctxt->postponed) |
| 274 | authmsg = "Postponed"; |
| 275 | else |
| 276 | authmsg = authenticated ? "Accepted" : "Failed"; |
| 277 | |
| 278 | authlog("%s %s for %s%.100s from %.200s port %d%s", |
| 279 | authmsg, |
| 280 | method, |
| 281 | authctxt->valid ? "" : "illegal user ", |
Damien Miller | f655207 | 2001-11-12 11:06:06 +1100 | [diff] [blame] | 282 | authctxt->user, |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 283 | get_remote_ipaddr(), |
| 284 | get_remote_port(), |
| 285 | info); |
Ben Lindstrom | e06eb68 | 2002-07-04 00:27:21 +0000 | [diff] [blame] | 286 | |
| 287 | #ifdef WITH_AIXAUTHENTICATE |
| 288 | if (authenticated == 0 && strcmp(method, "password") == 0) |
| 289 | loginfailed(authctxt->user, |
| 290 | get_canonical_hostname(options.verify_reverse_mapping), |
| 291 | "ssh"); |
| 292 | #endif /* WITH_AIXAUTHENTICATE */ |
| 293 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 294 | } |
| 295 | |
| 296 | /* |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 297 | * Check whether root logins are disallowed. |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 298 | */ |
| 299 | int |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 300 | auth_root_allowed(char *method) |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 301 | { |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 302 | switch (options.permit_root_login) { |
| 303 | case PERMIT_YES: |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 304 | return 1; |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 305 | break; |
| 306 | case PERMIT_NO_PASSWD: |
| 307 | if (strcmp(method, "password") != 0) |
| 308 | return 1; |
| 309 | break; |
| 310 | case PERMIT_FORCED_ONLY: |
| 311 | if (forced_command) { |
| 312 | log("Root login accepted for forced command."); |
| 313 | return 1; |
| 314 | } |
| 315 | break; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 316 | } |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 317 | log("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr()); |
| 318 | return 0; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 319 | } |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 320 | |
| 321 | |
| 322 | /* |
| 323 | * Given a template and a passwd structure, build a filename |
| 324 | * by substituting % tokenised options. Currently, %% becomes '%', |
| 325 | * %h becomes the home directory and %u the username. |
| 326 | * |
| 327 | * This returns a buffer allocated by xmalloc. |
| 328 | */ |
| 329 | char * |
| 330 | expand_filename(const char *filename, struct passwd *pw) |
| 331 | { |
| 332 | Buffer buffer; |
| 333 | char *file; |
| 334 | const char *cp; |
| 335 | |
| 336 | /* |
| 337 | * Build the filename string in the buffer by making the appropriate |
| 338 | * substitutions to the given file name. |
| 339 | */ |
| 340 | buffer_init(&buffer); |
| 341 | for (cp = filename; *cp; cp++) { |
| 342 | if (cp[0] == '%' && cp[1] == '%') { |
| 343 | buffer_append(&buffer, "%", 1); |
| 344 | cp++; |
| 345 | continue; |
| 346 | } |
| 347 | if (cp[0] == '%' && cp[1] == 'h') { |
| 348 | buffer_append(&buffer, pw->pw_dir, strlen(pw->pw_dir)); |
| 349 | cp++; |
| 350 | continue; |
| 351 | } |
| 352 | if (cp[0] == '%' && cp[1] == 'u') { |
| 353 | buffer_append(&buffer, pw->pw_name, |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 354 | strlen(pw->pw_name)); |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 355 | cp++; |
| 356 | continue; |
| 357 | } |
| 358 | buffer_append(&buffer, cp, 1); |
| 359 | } |
| 360 | buffer_append(&buffer, "\0", 1); |
| 361 | |
| 362 | /* |
| 363 | * Ensure that filename starts anchored. If not, be backward |
| 364 | * compatible and prepend the '%h/' |
| 365 | */ |
| 366 | file = xmalloc(MAXPATHLEN); |
| 367 | cp = buffer_ptr(&buffer); |
| 368 | if (*cp != '/') |
| 369 | snprintf(file, MAXPATHLEN, "%s/%s", pw->pw_dir, cp); |
| 370 | else |
| 371 | strlcpy(file, cp, MAXPATHLEN); |
| 372 | |
| 373 | buffer_free(&buffer); |
| 374 | return file; |
| 375 | } |
| 376 | |
| 377 | char * |
| 378 | authorized_keys_file(struct passwd *pw) |
| 379 | { |
| 380 | return expand_filename(options.authorized_keys_file, pw); |
| 381 | } |
| 382 | |
| 383 | char * |
| 384 | authorized_keys_file2(struct passwd *pw) |
| 385 | { |
| 386 | return expand_filename(options.authorized_keys_file2, pw); |
| 387 | } |
| 388 | |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 389 | /* return ok if key exists in sysfile or userfile */ |
| 390 | HostStatus |
| 391 | check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host, |
| 392 | const char *sysfile, const char *userfile) |
| 393 | { |
| 394 | Key *found; |
| 395 | char *user_hostfile; |
| 396 | struct stat st; |
Ben Lindstrom | 65366a8 | 2001-12-06 16:32:47 +0000 | [diff] [blame] | 397 | HostStatus host_status; |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 398 | |
| 399 | /* Check if we know the host and its host key. */ |
| 400 | found = key_new(key->type); |
| 401 | host_status = check_host_in_hostfile(sysfile, host, key, found, NULL); |
| 402 | |
| 403 | if (host_status != HOST_OK && userfile != NULL) { |
| 404 | user_hostfile = tilde_expand_filename(userfile, pw->pw_uid); |
| 405 | if (options.strict_modes && |
| 406 | (stat(user_hostfile, &st) == 0) && |
| 407 | ((st.st_uid != 0 && st.st_uid != pw->pw_uid) || |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 408 | (st.st_mode & 022) != 0)) { |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 409 | log("Authentication refused for %.100s: " |
| 410 | "bad owner or modes for %.200s", |
| 411 | pw->pw_name, user_hostfile); |
| 412 | } else { |
| 413 | temporarily_use_uid(pw); |
| 414 | host_status = check_host_in_hostfile(user_hostfile, |
| 415 | host, key, found, NULL); |
| 416 | restore_uid(); |
| 417 | } |
| 418 | xfree(user_hostfile); |
| 419 | } |
| 420 | key_free(found); |
| 421 | |
| 422 | debug2("check_key_in_hostfiles: key %s for %s", host_status == HOST_OK ? |
| 423 | "ok" : "not found", host); |
| 424 | return host_status; |
| 425 | } |
| 426 | |
| 427 | |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 428 | /* |
| 429 | * Check a given file for security. This is defined as all components |
Ben Lindstrom | d4ee349 | 2002-08-20 18:42:13 +0000 | [diff] [blame] | 430 | * of the path to the file must be owned by either the owner of |
Ben Lindstrom | 60567ff | 2001-06-05 20:27:53 +0000 | [diff] [blame] | 431 | * 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] | 432 | * |
| 433 | * XXX Should any specific check be done for sym links ? |
| 434 | * |
| 435 | * Takes an open file descriptor, the file name, a uid and and |
| 436 | * error buffer plus max size as arguments. |
| 437 | * |
| 438 | * Returns 0 on success and -1 on failure |
| 439 | */ |
| 440 | int |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 441 | secure_filename(FILE *f, const char *file, struct passwd *pw, |
| 442 | char *err, size_t errlen) |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 443 | { |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 444 | uid_t uid = pw->pw_uid; |
Ben Lindstrom | c3e49e7 | 2001-10-03 17:55:26 +0000 | [diff] [blame] | 445 | char buf[MAXPATHLEN], homedir[MAXPATHLEN]; |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 446 | char *cp; |
Ben Lindstrom | 485075e | 2002-11-09 15:45:12 +0000 | [diff] [blame] | 447 | int comparehome = 0; |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 448 | struct stat st; |
| 449 | |
| 450 | if (realpath(file, buf) == NULL) { |
| 451 | snprintf(err, errlen, "realpath %s failed: %s", file, |
| 452 | strerror(errno)); |
| 453 | return -1; |
| 454 | } |
Ben Lindstrom | 485075e | 2002-11-09 15:45:12 +0000 | [diff] [blame] | 455 | if (realpath(pw->pw_dir, homedir) != NULL) |
| 456 | comparehome = 1; |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 457 | |
| 458 | /* check the open file to avoid races */ |
| 459 | if (fstat(fileno(f), &st) < 0 || |
| 460 | (st.st_uid != 0 && st.st_uid != uid) || |
| 461 | (st.st_mode & 022) != 0) { |
| 462 | snprintf(err, errlen, "bad ownership or modes for file %s", |
| 463 | buf); |
| 464 | return -1; |
| 465 | } |
| 466 | |
| 467 | /* for each component of the canonical path, walking upwards */ |
| 468 | for (;;) { |
| 469 | if ((cp = dirname(buf)) == NULL) { |
| 470 | snprintf(err, errlen, "dirname() failed"); |
| 471 | return -1; |
| 472 | } |
| 473 | strlcpy(buf, cp, sizeof(buf)); |
| 474 | |
| 475 | debug3("secure_filename: checking '%s'", buf); |
| 476 | if (stat(buf, &st) < 0 || |
| 477 | (st.st_uid != 0 && st.st_uid != uid) || |
| 478 | (st.st_mode & 022) != 0) { |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 479 | snprintf(err, errlen, |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 480 | "bad ownership or modes for directory %s", buf); |
| 481 | return -1; |
| 482 | } |
| 483 | |
Damien Miller | 0ae6e00 | 2001-07-14 12:21:34 +1000 | [diff] [blame] | 484 | /* If are passed the homedir then we can stop */ |
Ben Lindstrom | 485075e | 2002-11-09 15:45:12 +0000 | [diff] [blame] | 485 | if (comparehome && strcmp(homedir, buf) == 0) { |
Damien Miller | 0ae6e00 | 2001-07-14 12:21:34 +1000 | [diff] [blame] | 486 | debug3("secure_filename: terminating check at '%s'", |
| 487 | buf); |
| 488 | break; |
| 489 | } |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 490 | /* |
| 491 | * dirname should always complete with a "/" path, |
| 492 | * but we can be paranoid and check for "." too |
| 493 | */ |
| 494 | if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0)) |
| 495 | break; |
| 496 | } |
| 497 | return 0; |
| 498 | } |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 499 | |
| 500 | struct passwd * |
| 501 | getpwnamallow(const char *user) |
| 502 | { |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 503 | #ifdef HAVE_LOGIN_CAP |
| 504 | extern login_cap_t *lc; |
| 505 | #ifdef BSD_AUTH |
| 506 | auth_session_t *as; |
| 507 | #endif |
| 508 | #endif |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 509 | struct passwd *pw; |
| 510 | |
| 511 | pw = getpwnam(user); |
Damien Miller | 6f0a188 | 2002-09-22 01:26:51 +1000 | [diff] [blame] | 512 | if (pw == NULL) { |
| 513 | log("Illegal user %.100s from %.100s", |
| 514 | user, get_remote_ipaddr()); |
Ben Lindstrom | f5397c0 | 2002-11-09 16:11:10 +0000 | [diff] [blame] | 515 | #ifdef WITH_AIXAUTHENTICATE |
| 516 | loginfailed(user, |
| 517 | get_canonical_hostname(options.verify_reverse_mapping), |
| 518 | "ssh"); |
| 519 | #endif |
Damien Miller | 6f0a188 | 2002-09-22 01:26:51 +1000 | [diff] [blame] | 520 | return (NULL); |
| 521 | } |
| 522 | if (!allowed_user(pw)) |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 523 | return (NULL); |
| 524 | #ifdef HAVE_LOGIN_CAP |
| 525 | if ((lc = login_getclass(pw->pw_class)) == NULL) { |
| 526 | debug("unable to get login class: %s", user); |
| 527 | return (NULL); |
| 528 | } |
| 529 | #ifdef BSD_AUTH |
| 530 | if ((as = auth_open()) == NULL || auth_setpwd(as, pw) != 0 || |
Damien Miller | 13e35a0 | 2002-05-22 14:04:11 +1000 | [diff] [blame] | 531 | auth_approval(as, lc, pw->pw_name, "ssh") <= 0) { |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 532 | debug("Approval failure for %s", user); |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 533 | pw = NULL; |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 534 | } |
| 535 | if (as != NULL) |
| 536 | auth_close(as); |
| 537 | #endif |
| 538 | #endif |
Ben Lindstrom | f34e4eb | 2002-03-22 03:08:30 +0000 | [diff] [blame] | 539 | if (pw != NULL) |
| 540 | return (pwcopy(pw)); |
| 541 | return (NULL); |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 542 | } |
Ben Lindstrom | a574cda | 2002-05-15 16:16:14 +0000 | [diff] [blame] | 543 | |
| 544 | void |
| 545 | auth_debug_add(const char *fmt,...) |
| 546 | { |
| 547 | char buf[1024]; |
| 548 | va_list args; |
| 549 | |
| 550 | if (!auth_debug_init) |
| 551 | return; |
| 552 | |
| 553 | va_start(args, fmt); |
| 554 | vsnprintf(buf, sizeof(buf), fmt, args); |
| 555 | va_end(args); |
| 556 | buffer_put_cstring(&auth_debug, buf); |
| 557 | } |
| 558 | |
| 559 | void |
| 560 | auth_debug_send(void) |
| 561 | { |
| 562 | char *msg; |
| 563 | |
| 564 | if (!auth_debug_init) |
| 565 | return; |
| 566 | while (buffer_len(&auth_debug)) { |
| 567 | msg = buffer_get_string(&auth_debug, NULL); |
| 568 | packet_send_debug("%s", msg); |
| 569 | xfree(msg); |
| 570 | } |
| 571 | } |
| 572 | |
| 573 | void |
| 574 | auth_debug_reset(void) |
| 575 | { |
| 576 | if (auth_debug_init) |
| 577 | buffer_clear(&auth_debug); |
| 578 | else { |
| 579 | buffer_init(&auth_debug); |
| 580 | auth_debug_init = 1; |
| 581 | } |
| 582 | } |