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 */ |
Kevin Steves | a58e0af | 2000-10-29 14:38:55 +0000 | [diff] [blame] | 81 | #if !defined(USE_PAM) && defined(HAVE_SHADOW_H) && \ |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 82 | !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 83 | struct spwd *spw; |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 84 | #endif |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 85 | |
| 86 | /* 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] | 87 | if (!pw || !pw->pw_name) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 88 | return 0; |
| 89 | |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 90 | #if !defined(USE_PAM) && defined(HAVE_SHADOW_H) && \ |
| 91 | !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) |
Kevin Steves | f98fb72 | 2002-05-10 15:48:52 +0000 | [diff] [blame] | 92 | #define DAY (24L * 60 * 60) /* 1 day in seconds */ |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 93 | spw = getspnam(pw->pw_name); |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 94 | if (spw != NULL) { |
Kevin Steves | f98fb72 | 2002-05-10 15:48:52 +0000 | [diff] [blame] | 95 | time_t today = time(NULL) / DAY; |
| 96 | debug3("allowed_user: today %d sp_expire %d sp_lstchg %d" |
| 97 | " sp_max %d", (int)today, (int)spw->sp_expire, |
| 98 | (int)spw->sp_lstchg, (int)spw->sp_max); |
Damien Miller | 1f335fb | 2000-06-26 11:31:33 +1000 | [diff] [blame] | 99 | |
Kevin Steves | f98fb72 | 2002-05-10 15:48:52 +0000 | [diff] [blame] | 100 | /* |
| 101 | * We assume account and password expiration occurs the |
| 102 | * day after the day specified. |
| 103 | */ |
| 104 | if (spw->sp_expire != -1 && today > spw->sp_expire) { |
| 105 | log("Account %.100s has expired", pw->pw_name); |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 106 | return 0; |
Kevin Steves | f98fb72 | 2002-05-10 15:48:52 +0000 | [diff] [blame] | 107 | } |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 108 | |
Kevin Steves | f98fb72 | 2002-05-10 15:48:52 +0000 | [diff] [blame] | 109 | if (spw->sp_lstchg == 0) { |
| 110 | log("User %.100s password has expired (root forced)", |
| 111 | pw->pw_name); |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 112 | return 0; |
Kevin Steves | f98fb72 | 2002-05-10 15:48:52 +0000 | [diff] [blame] | 113 | } |
| 114 | |
| 115 | if (spw->sp_max != -1 && |
| 116 | today > spw->sp_lstchg + spw->sp_max) { |
| 117 | log("User %.100s password has expired (password aged)", |
| 118 | pw->pw_name); |
| 119 | return 0; |
| 120 | } |
Damien Miller | c708843 | 2000-07-02 18:44:54 +1000 | [diff] [blame] | 121 | } |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 122 | passwd = spw->sp_pwdp; |
| 123 | #else |
| 124 | passwd = pw->pw_passwd; |
| 125 | #endif |
Damien Miller | 64004b5 | 2003-01-07 16:15:20 +1100 | [diff] [blame^] | 126 | |
Damien Miller | 48cb8aa | 2003-01-07 12:19:32 +1100 | [diff] [blame] | 127 | /* check for locked account */ |
| 128 | if (strcmp(passwd, "*LK*") == 0 || passwd[0] == '!') { |
| 129 | log("User %.100s not allowed because account is locked", |
| 130 | pw->pw_name); |
| 131 | return 0; |
| 132 | } |
| 133 | |
Damien Miller | ef7df54 | 2000-05-19 00:03:23 +1000 | [diff] [blame] | 134 | /* |
| 135 | * Get the shell from the password data. An empty shell field is |
| 136 | * legal, and means /bin/sh. |
| 137 | */ |
| 138 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; |
| 139 | |
| 140 | /* deny if shell does not exists or is not executable */ |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 141 | if (stat(shell, &st) != 0) { |
| 142 | log("User %.100s not allowed because shell %.100s does not exist", |
| 143 | pw->pw_name, shell); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 144 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 145 | } |
Ben Lindstrom | b61e6df | 2002-03-22 01:15:33 +0000 | [diff] [blame] | 146 | if (S_ISREG(st.st_mode) == 0 || |
| 147 | (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) { |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 148 | log("User %.100s not allowed because shell %.100s is not executable", |
| 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 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 152 | |
Ben Lindstrom | 3fb5d00 | 2002-03-05 01:42:42 +0000 | [diff] [blame] | 153 | if (options.num_deny_users > 0 || options.num_allow_users > 0) { |
| 154 | hostname = get_canonical_hostname(options.verify_reverse_mapping); |
| 155 | ipaddr = get_remote_ipaddr(); |
| 156 | } |
| 157 | |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 158 | /* Return false if user is listed in DenyUsers */ |
| 159 | if (options.num_deny_users > 0) { |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 160 | for (i = 0; i < options.num_deny_users; i++) |
Ben Lindstrom | 6328ab3 | 2002-03-22 02:54:23 +0000 | [diff] [blame] | 161 | if (match_user(pw->pw_name, hostname, ipaddr, |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 162 | options.deny_users[i])) { |
Ben Lindstrom | 6328ab3 | 2002-03-22 02:54:23 +0000 | [diff] [blame] | 163 | log("User %.100s not allowed because listed in DenyUsers", |
| 164 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 165 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 166 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 167 | } |
| 168 | /* Return false if AllowUsers isn't empty and user isn't listed there */ |
| 169 | if (options.num_allow_users > 0) { |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 170 | for (i = 0; i < options.num_allow_users; i++) |
Ben Lindstrom | 6328ab3 | 2002-03-22 02:54:23 +0000 | [diff] [blame] | 171 | if (match_user(pw->pw_name, hostname, ipaddr, |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 172 | options.allow_users[i])) |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 173 | break; |
| 174 | /* i < options.num_allow_users iff we break for loop */ |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 175 | if (i >= options.num_allow_users) { |
| 176 | log("User %.100s not allowed because not listed in AllowUsers", |
| 177 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 178 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 179 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 180 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 181 | if (options.num_deny_groups > 0 || options.num_allow_groups > 0) { |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 182 | /* Get the user's group access list (primary and supplementary) */ |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 183 | if (ga_init(pw->pw_name, pw->pw_gid) == 0) { |
| 184 | log("User %.100s not allowed because not in any group", |
| 185 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 186 | return 0; |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 187 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 188 | |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 189 | /* Return false if one of user's groups is listed in DenyGroups */ |
| 190 | if (options.num_deny_groups > 0) |
| 191 | if (ga_match(options.deny_groups, |
| 192 | options.num_deny_groups)) { |
| 193 | ga_free(); |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 194 | log("User %.100s not allowed because a group is listed in DenyGroups", |
| 195 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 196 | return 0; |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 197 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 198 | /* |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 199 | * 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] | 200 | * isn't listed there |
| 201 | */ |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 202 | if (options.num_allow_groups > 0) |
| 203 | if (!ga_match(options.allow_groups, |
| 204 | options.num_allow_groups)) { |
| 205 | ga_free(); |
Ben Lindstrom | 6ef9ec6 | 2002-03-05 01:40:37 +0000 | [diff] [blame] | 206 | log("User %.100s not allowed because none of user's groups are listed in AllowGroups", |
| 207 | pw->pw_name); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 208 | return 0; |
Kevin Steves | 7b61cfa | 2001-01-14 19:11:00 +0000 | [diff] [blame] | 209 | } |
| 210 | ga_free(); |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 211 | } |
| 212 | |
| 213 | #ifdef WITH_AIXAUTHENTICATE |
Ben Lindstrom | 97e38d8 | 2002-10-16 00:13:52 +0000 | [diff] [blame] | 214 | /* |
| 215 | * Don't check loginrestrictions() for root account (use |
| 216 | * PermitRootLogin to control logins via ssh), or if running as |
| 217 | * non-root user (since loginrestrictions will always fail). |
| 218 | */ |
| 219 | if ( (pw->pw_uid != 0) && (geteuid() == 0) && |
| 220 | loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) { |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 221 | if (loginmsg && *loginmsg) { |
| 222 | /* Remove embedded newlines (if any) */ |
| 223 | char *p; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 224 | for (p = loginmsg; *p; p++) { |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 225 | if (*p == '\n') |
| 226 | *p = ' '; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 227 | } |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 228 | /* Remove trailing newline */ |
| 229 | *--p = '\0'; |
Damien Miller | 2f6a0ad | 2000-05-31 11:20:11 +1000 | [diff] [blame] | 230 | log("Login restricted for %s: %.100s", pw->pw_name, loginmsg); |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 231 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 232 | return 0; |
Damien Miller | d2c208a | 2000-05-17 22:00:02 +1000 | [diff] [blame] | 233 | } |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame] | 234 | #endif /* WITH_AIXAUTHENTICATE */ |
| 235 | |
| 236 | /* We found no reason not to let this user try to log on... */ |
| 237 | return 1; |
| 238 | } |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 239 | |
| 240 | Authctxt * |
| 241 | authctxt_new(void) |
| 242 | { |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 243 | Authctxt *authctxt = xmalloc(sizeof(*authctxt)); |
| 244 | memset(authctxt, 0, sizeof(*authctxt)); |
| 245 | return authctxt; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 246 | } |
| 247 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 248 | void |
| 249 | auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) |
| 250 | { |
| 251 | void (*authlog) (const char *fmt,...) = verbose; |
| 252 | char *authmsg; |
| 253 | |
| 254 | /* Raise logging level */ |
| 255 | if (authenticated == 1 || |
| 256 | !authctxt->valid || |
| 257 | authctxt->failures >= AUTH_FAIL_LOG || |
| 258 | strcmp(method, "password") == 0) |
| 259 | authlog = log; |
| 260 | |
| 261 | if (authctxt->postponed) |
| 262 | authmsg = "Postponed"; |
| 263 | else |
| 264 | authmsg = authenticated ? "Accepted" : "Failed"; |
| 265 | |
| 266 | authlog("%s %s for %s%.100s from %.200s port %d%s", |
| 267 | authmsg, |
| 268 | method, |
| 269 | authctxt->valid ? "" : "illegal user ", |
Damien Miller | f655207 | 2001-11-12 11:06:06 +1100 | [diff] [blame] | 270 | authctxt->user, |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 271 | get_remote_ipaddr(), |
| 272 | get_remote_port(), |
| 273 | info); |
Ben Lindstrom | e06eb68 | 2002-07-04 00:27:21 +0000 | [diff] [blame] | 274 | |
| 275 | #ifdef WITH_AIXAUTHENTICATE |
| 276 | if (authenticated == 0 && strcmp(method, "password") == 0) |
| 277 | loginfailed(authctxt->user, |
| 278 | get_canonical_hostname(options.verify_reverse_mapping), |
| 279 | "ssh"); |
| 280 | #endif /* WITH_AIXAUTHENTICATE */ |
| 281 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 282 | } |
| 283 | |
| 284 | /* |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 285 | * Check whether root logins are disallowed. |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 286 | */ |
| 287 | int |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 288 | auth_root_allowed(char *method) |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 289 | { |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 290 | switch (options.permit_root_login) { |
| 291 | case PERMIT_YES: |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 292 | return 1; |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 293 | break; |
| 294 | case PERMIT_NO_PASSWD: |
| 295 | if (strcmp(method, "password") != 0) |
| 296 | return 1; |
| 297 | break; |
| 298 | case PERMIT_FORCED_ONLY: |
| 299 | if (forced_command) { |
| 300 | log("Root login accepted for forced command."); |
| 301 | return 1; |
| 302 | } |
| 303 | break; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 304 | } |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 305 | log("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr()); |
| 306 | return 0; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 307 | } |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 308 | |
| 309 | |
| 310 | /* |
| 311 | * Given a template and a passwd structure, build a filename |
| 312 | * by substituting % tokenised options. Currently, %% becomes '%', |
| 313 | * %h becomes the home directory and %u the username. |
| 314 | * |
| 315 | * This returns a buffer allocated by xmalloc. |
| 316 | */ |
| 317 | char * |
| 318 | expand_filename(const char *filename, struct passwd *pw) |
| 319 | { |
| 320 | Buffer buffer; |
| 321 | char *file; |
| 322 | const char *cp; |
| 323 | |
| 324 | /* |
| 325 | * Build the filename string in the buffer by making the appropriate |
| 326 | * substitutions to the given file name. |
| 327 | */ |
| 328 | buffer_init(&buffer); |
| 329 | for (cp = filename; *cp; cp++) { |
| 330 | if (cp[0] == '%' && cp[1] == '%') { |
| 331 | buffer_append(&buffer, "%", 1); |
| 332 | cp++; |
| 333 | continue; |
| 334 | } |
| 335 | if (cp[0] == '%' && cp[1] == 'h') { |
| 336 | buffer_append(&buffer, pw->pw_dir, strlen(pw->pw_dir)); |
| 337 | cp++; |
| 338 | continue; |
| 339 | } |
| 340 | if (cp[0] == '%' && cp[1] == 'u') { |
| 341 | buffer_append(&buffer, pw->pw_name, |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 342 | strlen(pw->pw_name)); |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 343 | cp++; |
| 344 | continue; |
| 345 | } |
| 346 | buffer_append(&buffer, cp, 1); |
| 347 | } |
| 348 | buffer_append(&buffer, "\0", 1); |
| 349 | |
| 350 | /* |
| 351 | * Ensure that filename starts anchored. If not, be backward |
| 352 | * compatible and prepend the '%h/' |
| 353 | */ |
| 354 | file = xmalloc(MAXPATHLEN); |
| 355 | cp = buffer_ptr(&buffer); |
| 356 | if (*cp != '/') |
| 357 | snprintf(file, MAXPATHLEN, "%s/%s", pw->pw_dir, cp); |
| 358 | else |
| 359 | strlcpy(file, cp, MAXPATHLEN); |
| 360 | |
| 361 | buffer_free(&buffer); |
| 362 | return file; |
| 363 | } |
| 364 | |
| 365 | char * |
| 366 | authorized_keys_file(struct passwd *pw) |
| 367 | { |
| 368 | return expand_filename(options.authorized_keys_file, pw); |
| 369 | } |
| 370 | |
| 371 | char * |
| 372 | authorized_keys_file2(struct passwd *pw) |
| 373 | { |
| 374 | return expand_filename(options.authorized_keys_file2, pw); |
| 375 | } |
| 376 | |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 377 | /* return ok if key exists in sysfile or userfile */ |
| 378 | HostStatus |
| 379 | check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host, |
| 380 | const char *sysfile, const char *userfile) |
| 381 | { |
| 382 | Key *found; |
| 383 | char *user_hostfile; |
| 384 | struct stat st; |
Ben Lindstrom | 65366a8 | 2001-12-06 16:32:47 +0000 | [diff] [blame] | 385 | HostStatus host_status; |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 386 | |
| 387 | /* Check if we know the host and its host key. */ |
| 388 | found = key_new(key->type); |
| 389 | host_status = check_host_in_hostfile(sysfile, host, key, found, NULL); |
| 390 | |
| 391 | if (host_status != HOST_OK && userfile != NULL) { |
| 392 | user_hostfile = tilde_expand_filename(userfile, pw->pw_uid); |
| 393 | if (options.strict_modes && |
| 394 | (stat(user_hostfile, &st) == 0) && |
| 395 | ((st.st_uid != 0 && st.st_uid != pw->pw_uid) || |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 396 | (st.st_mode & 022) != 0)) { |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 397 | log("Authentication refused for %.100s: " |
| 398 | "bad owner or modes for %.200s", |
| 399 | pw->pw_name, user_hostfile); |
| 400 | } else { |
| 401 | temporarily_use_uid(pw); |
| 402 | host_status = check_host_in_hostfile(user_hostfile, |
| 403 | host, key, found, NULL); |
| 404 | restore_uid(); |
| 405 | } |
| 406 | xfree(user_hostfile); |
| 407 | } |
| 408 | key_free(found); |
| 409 | |
| 410 | debug2("check_key_in_hostfiles: key %s for %s", host_status == HOST_OK ? |
| 411 | "ok" : "not found", host); |
| 412 | return host_status; |
| 413 | } |
| 414 | |
| 415 | |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 416 | /* |
| 417 | * Check a given file for security. This is defined as all components |
Ben Lindstrom | d4ee349 | 2002-08-20 18:42:13 +0000 | [diff] [blame] | 418 | * 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] | 419 | * 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] | 420 | * |
| 421 | * XXX Should any specific check be done for sym links ? |
| 422 | * |
| 423 | * Takes an open file descriptor, the file name, a uid and and |
| 424 | * error buffer plus max size as arguments. |
| 425 | * |
| 426 | * Returns 0 on success and -1 on failure |
| 427 | */ |
| 428 | int |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 429 | secure_filename(FILE *f, const char *file, struct passwd *pw, |
| 430 | char *err, size_t errlen) |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 431 | { |
Ben Lindstrom | 248c078 | 2001-07-04 03:40:39 +0000 | [diff] [blame] | 432 | uid_t uid = pw->pw_uid; |
Ben Lindstrom | c3e49e7 | 2001-10-03 17:55:26 +0000 | [diff] [blame] | 433 | char buf[MAXPATHLEN], homedir[MAXPATHLEN]; |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 434 | char *cp; |
Ben Lindstrom | 485075e | 2002-11-09 15:45:12 +0000 | [diff] [blame] | 435 | int comparehome = 0; |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 436 | struct stat st; |
| 437 | |
| 438 | if (realpath(file, buf) == NULL) { |
| 439 | snprintf(err, errlen, "realpath %s failed: %s", file, |
| 440 | strerror(errno)); |
| 441 | return -1; |
| 442 | } |
Ben Lindstrom | 485075e | 2002-11-09 15:45:12 +0000 | [diff] [blame] | 443 | if (realpath(pw->pw_dir, homedir) != NULL) |
| 444 | comparehome = 1; |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 445 | |
| 446 | /* check the open file to avoid races */ |
| 447 | if (fstat(fileno(f), &st) < 0 || |
| 448 | (st.st_uid != 0 && st.st_uid != uid) || |
| 449 | (st.st_mode & 022) != 0) { |
| 450 | snprintf(err, errlen, "bad ownership or modes for file %s", |
| 451 | buf); |
| 452 | return -1; |
| 453 | } |
| 454 | |
| 455 | /* for each component of the canonical path, walking upwards */ |
| 456 | for (;;) { |
| 457 | if ((cp = dirname(buf)) == NULL) { |
| 458 | snprintf(err, errlen, "dirname() failed"); |
| 459 | return -1; |
| 460 | } |
| 461 | strlcpy(buf, cp, sizeof(buf)); |
| 462 | |
| 463 | debug3("secure_filename: checking '%s'", buf); |
| 464 | if (stat(buf, &st) < 0 || |
| 465 | (st.st_uid != 0 && st.st_uid != uid) || |
| 466 | (st.st_mode & 022) != 0) { |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 467 | snprintf(err, errlen, |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 468 | "bad ownership or modes for directory %s", buf); |
| 469 | return -1; |
| 470 | } |
| 471 | |
Damien Miller | 0ae6e00 | 2001-07-14 12:21:34 +1000 | [diff] [blame] | 472 | /* If are passed the homedir then we can stop */ |
Ben Lindstrom | 485075e | 2002-11-09 15:45:12 +0000 | [diff] [blame] | 473 | if (comparehome && strcmp(homedir, buf) == 0) { |
Damien Miller | 0ae6e00 | 2001-07-14 12:21:34 +1000 | [diff] [blame] | 474 | debug3("secure_filename: terminating check at '%s'", |
| 475 | buf); |
| 476 | break; |
| 477 | } |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 478 | /* |
| 479 | * dirname should always complete with a "/" path, |
| 480 | * but we can be paranoid and check for "." too |
| 481 | */ |
| 482 | if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0)) |
| 483 | break; |
| 484 | } |
| 485 | return 0; |
| 486 | } |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 487 | |
| 488 | struct passwd * |
| 489 | getpwnamallow(const char *user) |
| 490 | { |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 491 | #ifdef HAVE_LOGIN_CAP |
| 492 | extern login_cap_t *lc; |
| 493 | #ifdef BSD_AUTH |
| 494 | auth_session_t *as; |
| 495 | #endif |
| 496 | #endif |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 497 | struct passwd *pw; |
| 498 | |
| 499 | pw = getpwnam(user); |
Damien Miller | 6f0a188 | 2002-09-22 01:26:51 +1000 | [diff] [blame] | 500 | if (pw == NULL) { |
| 501 | log("Illegal user %.100s from %.100s", |
| 502 | user, get_remote_ipaddr()); |
Ben Lindstrom | f5397c0 | 2002-11-09 16:11:10 +0000 | [diff] [blame] | 503 | #ifdef WITH_AIXAUTHENTICATE |
| 504 | loginfailed(user, |
| 505 | get_canonical_hostname(options.verify_reverse_mapping), |
| 506 | "ssh"); |
| 507 | #endif |
Damien Miller | 6f0a188 | 2002-09-22 01:26:51 +1000 | [diff] [blame] | 508 | return (NULL); |
| 509 | } |
| 510 | if (!allowed_user(pw)) |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 511 | return (NULL); |
| 512 | #ifdef HAVE_LOGIN_CAP |
| 513 | if ((lc = login_getclass(pw->pw_class)) == NULL) { |
| 514 | debug("unable to get login class: %s", user); |
| 515 | return (NULL); |
| 516 | } |
| 517 | #ifdef BSD_AUTH |
| 518 | if ((as = auth_open()) == NULL || auth_setpwd(as, pw) != 0 || |
Damien Miller | 13e35a0 | 2002-05-22 14:04:11 +1000 | [diff] [blame] | 519 | auth_approval(as, lc, pw->pw_name, "ssh") <= 0) { |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 520 | debug("Approval failure for %s", user); |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 521 | pw = NULL; |
Ben Lindstrom | b481e13 | 2002-03-22 01:35:47 +0000 | [diff] [blame] | 522 | } |
| 523 | if (as != NULL) |
| 524 | auth_close(as); |
| 525 | #endif |
| 526 | #endif |
Ben Lindstrom | f34e4eb | 2002-03-22 03:08:30 +0000 | [diff] [blame] | 527 | if (pw != NULL) |
| 528 | return (pwcopy(pw)); |
| 529 | return (NULL); |
Ben Lindstrom | 2ae18f4 | 2002-03-22 01:24:38 +0000 | [diff] [blame] | 530 | } |
Ben Lindstrom | a574cda | 2002-05-15 16:16:14 +0000 | [diff] [blame] | 531 | |
| 532 | void |
| 533 | auth_debug_add(const char *fmt,...) |
| 534 | { |
| 535 | char buf[1024]; |
| 536 | va_list args; |
| 537 | |
| 538 | if (!auth_debug_init) |
| 539 | return; |
| 540 | |
| 541 | va_start(args, fmt); |
| 542 | vsnprintf(buf, sizeof(buf), fmt, args); |
| 543 | va_end(args); |
| 544 | buffer_put_cstring(&auth_debug, buf); |
| 545 | } |
| 546 | |
| 547 | void |
| 548 | auth_debug_send(void) |
| 549 | { |
| 550 | char *msg; |
| 551 | |
| 552 | if (!auth_debug_init) |
| 553 | return; |
| 554 | while (buffer_len(&auth_debug)) { |
| 555 | msg = buffer_get_string(&auth_debug, NULL); |
| 556 | packet_send_debug("%s", msg); |
| 557 | xfree(msg); |
| 558 | } |
| 559 | } |
| 560 | |
| 561 | void |
| 562 | auth_debug_reset(void) |
| 563 | { |
| 564 | if (auth_debug_init) |
| 565 | buffer_clear(&auth_debug); |
| 566 | else { |
| 567 | buffer_init(&auth_debug); |
| 568 | auth_debug_init = 1; |
| 569 | } |
| 570 | } |