markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 1 | /* $OpenBSD: auth-passwd.c,v 1.47 2018/07/09 21:26:02 markus Exp $ */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 2 | /* |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
| 4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 5 | * All rights reserved |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 6 | * Password authentication. This file contains the functions to check whether |
| 7 | * the password is valid for the user. |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 8 | * |
| 9 | * As far as I am concerned, the code I have written for this software |
| 10 | * can be used freely for any purpose. Any derived versions of this |
| 11 | * software must be clearly marked as such, and if the derived work is |
| 12 | * incompatible with the protocol description in the RFC file, it must be |
| 13 | * called by a name other than "ssh" or "Secure Shell". |
| 14 | * |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 15 | * Copyright (c) 1999 Dug Song. All rights reserved. |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 16 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
| 17 | * |
| 18 | * Redistribution and use in source and binary forms, with or without |
| 19 | * modification, are permitted provided that the following conditions |
| 20 | * are met: |
| 21 | * 1. Redistributions of source code must retain the above copyright |
| 22 | * notice, this list of conditions and the following disclaimer. |
| 23 | * 2. Redistributions in binary form must reproduce the above copyright |
| 24 | * notice, this list of conditions and the following disclaimer in the |
| 25 | * documentation and/or other materials provided with the distribution. |
| 26 | * |
| 27 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 28 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 29 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 30 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 31 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 32 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 33 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 34 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 35 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 36 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 37 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 38 | |
| 39 | #include "includes.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 40 | |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 41 | #include <sys/types.h> |
| 42 | |
| 43 | #include <pwd.h> |
Damien Miller | a7a73ee | 2006-08-05 11:37:59 +1000 | [diff] [blame] | 44 | #include <stdio.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame] | 45 | #include <string.h> |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 46 | #include <stdarg.h> |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 47 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 48 | #include "packet.h" |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 49 | #include "sshbuf.h" |
| 50 | #include "ssherr.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 51 | #include "log.h" |
Damien Miller | 7acefbb | 2014-07-18 14:11:24 +1000 | [diff] [blame] | 52 | #include "misc.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 53 | #include "servconf.h" |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 54 | #include "sshkey.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 55 | #include "hostfile.h" |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 56 | #include "auth.h" |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 57 | #include "auth-options.h" |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 58 | |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 59 | extern struct sshbuf *loginmsg; |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 60 | extern ServerOptions options; |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 61 | |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 62 | #ifdef HAVE_LOGIN_CAP |
| 63 | extern login_cap_t *lc; |
| 64 | #endif |
| 65 | |
| 66 | |
| 67 | #define DAY (24L * 60 * 60) /* 1 day in seconds */ |
| 68 | #define TWO_WEEKS (2L * 7 * DAY) /* 2 weeks in seconds */ |
| 69 | |
dtucker@openbsd.org | fcd135c | 2016-07-21 01:39:35 +0000 | [diff] [blame] | 70 | #define MAX_PASSWORD_LEN 1024 |
| 71 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 72 | /* |
| 73 | * Tries to authenticate the user using password. Returns true if |
| 74 | * authentication succeeds. |
| 75 | */ |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 76 | int |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 77 | auth_password(struct ssh *ssh, const char *password) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 78 | { |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 79 | Authctxt *authctxt = ssh->authctxt; |
| 80 | struct passwd *pw = authctxt->pw; |
Darren Tucker | 92170a8 | 2005-02-09 17:08:23 +1100 | [diff] [blame] | 81 | int result, ok = authctxt->valid; |
Ben Lindstrom | e35bf12 | 2004-06-22 03:37:11 +0000 | [diff] [blame] | 82 | #if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) |
Darren Tucker | b4dc6c2 | 2004-02-22 10:23:35 +1100 | [diff] [blame] | 83 | static int expire_checked = 0; |
Ben Lindstrom | e35bf12 | 2004-06-22 03:37:11 +0000 | [diff] [blame] | 84 | #endif |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 85 | |
dtucker@openbsd.org | fcd135c | 2016-07-21 01:39:35 +0000 | [diff] [blame] | 86 | if (strlen(password) > MAX_PASSWORD_LEN) |
| 87 | return 0; |
| 88 | |
Damien Miller | bac2d8a | 2000-09-05 16:13:06 +1100 | [diff] [blame] | 89 | #ifndef HAVE_CYGWIN |
Damien Miller | 3e3b514 | 2003-11-17 21:13:40 +1100 | [diff] [blame] | 90 | if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES) |
Damien Miller | eab4bae | 2003-04-29 23:22:40 +1000 | [diff] [blame] | 91 | ok = 0; |
Damien Miller | bac2d8a | 2000-09-05 16:13:06 +1100 | [diff] [blame] | 92 | #endif |
Ben Lindstrom | 0b47814 | 2002-05-10 02:40:15 +0000 | [diff] [blame] | 93 | if (*password == '\0' && options.permit_empty_passwd == 0) |
Damien Miller | eab4bae | 2003-04-29 23:22:40 +1000 | [diff] [blame] | 94 | return 0; |
Ben Lindstrom | 0410e32 | 2003-07-24 06:52:13 +0000 | [diff] [blame] | 95 | |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 96 | #ifdef KRB5 |
Ben Lindstrom | ec95ed9 | 2001-07-04 04:21:14 +0000 | [diff] [blame] | 97 | if (options.kerberos_authentication == 1) { |
| 98 | int ret = auth_krb5_password(authctxt, password); |
| 99 | if (ret == 1 || ret == 0) |
Damien Miller | 856f0be | 2003-09-03 07:32:45 +1000 | [diff] [blame] | 100 | return ret && ok; |
Ben Lindstrom | ec95ed9 | 2001-07-04 04:21:14 +0000 | [diff] [blame] | 101 | /* Fall back to ordinary passwd authentication. */ |
| 102 | } |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 103 | #endif |
| 104 | #ifdef HAVE_CYGWIN |
Darren Tucker | 9d86e5d | 2009-03-08 11:40:27 +1100 | [diff] [blame] | 105 | { |
Damien Miller | bac2d8a | 2000-09-05 16:13:06 +1100 | [diff] [blame] | 106 | HANDLE hToken = cygwin_logon_user(pw, password); |
| 107 | |
| 108 | if (hToken == INVALID_HANDLE_VALUE) |
Damien Miller | 856f0be | 2003-09-03 07:32:45 +1000 | [diff] [blame] | 109 | return 0; |
Damien Miller | bac2d8a | 2000-09-05 16:13:06 +1100 | [diff] [blame] | 110 | cygwin_set_impersonation_token(hToken); |
Damien Miller | 856f0be | 2003-09-03 07:32:45 +1000 | [diff] [blame] | 111 | return ok; |
Damien Miller | bac2d8a | 2000-09-05 16:13:06 +1100 | [diff] [blame] | 112 | } |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 113 | #endif |
Darren Tucker | 450a158 | 2004-05-30 20:43:59 +1000 | [diff] [blame] | 114 | #ifdef USE_PAM |
| 115 | if (options.use_pam) |
| 116 | return (sshpam_auth_passwd(authctxt, password) && ok); |
| 117 | #endif |
Darren Tucker | cee6d4c | 2004-02-11 18:48:52 +1100 | [diff] [blame] | 118 | #if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) |
Darren Tucker | b4dc6c2 | 2004-02-22 10:23:35 +1100 | [diff] [blame] | 119 | if (!expire_checked) { |
| 120 | expire_checked = 1; |
Darren Tucker | 92170a8 | 2005-02-09 17:08:23 +1100 | [diff] [blame] | 121 | if (auth_shadow_pwexpired(authctxt)) |
Darren Tucker | b4dc6c2 | 2004-02-22 10:23:35 +1100 | [diff] [blame] | 122 | authctxt->force_pwchange = 1; |
Darren Tucker | 9df3def | 2004-02-10 13:01:14 +1100 | [diff] [blame] | 123 | } |
| 124 | #endif |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 125 | result = sys_auth_passwd(ssh, password); |
Darren Tucker | 92170a8 | 2005-02-09 17:08:23 +1100 | [diff] [blame] | 126 | if (authctxt->force_pwchange) |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 127 | auth_restrict_session(ssh); |
Darren Tucker | 92170a8 | 2005-02-09 17:08:23 +1100 | [diff] [blame] | 128 | return (result && ok); |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 129 | } |
| 130 | |
| 131 | #ifdef BSD_AUTH |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 132 | static void |
| 133 | warn_expiry(Authctxt *authctxt, auth_session_t *as) |
| 134 | { |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 135 | int r; |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 136 | quad_t pwtimeleft, actimeleft, daysleft, pwwarntime, acwarntime; |
| 137 | |
| 138 | pwwarntime = acwarntime = TWO_WEEKS; |
| 139 | |
| 140 | pwtimeleft = auth_check_change(as); |
| 141 | actimeleft = auth_check_expire(as); |
Darren Tucker | 218f178 | 2005-01-24 22:50:47 +1100 | [diff] [blame] | 142 | #ifdef HAVE_LOGIN_CAP |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 143 | if (authctxt->valid) { |
| 144 | pwwarntime = login_getcaptime(lc, "password-warn", TWO_WEEKS, |
| 145 | TWO_WEEKS); |
| 146 | acwarntime = login_getcaptime(lc, "expire-warn", TWO_WEEKS, |
| 147 | TWO_WEEKS); |
| 148 | } |
| 149 | #endif |
| 150 | if (pwtimeleft != 0 && pwtimeleft < pwwarntime) { |
| 151 | daysleft = pwtimeleft / DAY + 1; |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 152 | if ((r = sshbuf_putf(loginmsg, |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 153 | "Your password will expire in %lld day%s.\n", |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 154 | daysleft, daysleft == 1 ? "" : "s")) != 0) |
| 155 | fatal("%s: buffer error: %s", __func__, ssh_err(r)); |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 156 | } |
| 157 | if (actimeleft != 0 && actimeleft < acwarntime) { |
| 158 | daysleft = actimeleft / DAY + 1; |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 159 | if ((r = sshbuf_putf(loginmsg, |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 160 | "Your account will expire in %lld day%s.\n", |
markus@openbsd.org | 2808d18 | 2018-07-09 21:26:02 +0000 | [diff] [blame] | 161 | daysleft, daysleft == 1 ? "" : "s")) != 0) |
| 162 | fatal("%s: buffer error: %s", __func__, ssh_err(r)); |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 163 | } |
| 164 | } |
| 165 | |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 166 | int |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 167 | sys_auth_passwd(struct ssh *ssh, const char *password) |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 168 | { |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 169 | Authctxt *authctxt = ssh->authctxt; |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 170 | auth_session_t *as; |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 171 | static int expire_checked = 0; |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 172 | |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 173 | as = auth_usercheck(authctxt->pw->pw_name, authctxt->style, "auth-ssh", |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 174 | (char *)password); |
Damien Miller | 47655ee | 2005-07-26 21:54:11 +1000 | [diff] [blame] | 175 | if (as == NULL) |
| 176 | return (0); |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 177 | if (auth_getstate(as) & AUTH_PWEXPIRED) { |
| 178 | auth_close(as); |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 179 | auth_restrict_session(ssh); |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 180 | authctxt->force_pwchange = 1; |
| 181 | return (1); |
| 182 | } else { |
Darren Tucker | 5c14c73 | 2005-01-24 21:55:49 +1100 | [diff] [blame] | 183 | if (!expire_checked) { |
| 184 | expire_checked = 1; |
| 185 | warn_expiry(authctxt, as); |
| 186 | } |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 187 | return (auth_close(as)); |
| 188 | } |
| 189 | } |
Darren Tucker | e3dba82 | 2004-02-10 12:50:19 +1100 | [diff] [blame] | 190 | #elif !defined(CUSTOM_SYS_AUTH_PASSWD) |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 191 | int |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 192 | sys_auth_passwd(struct ssh *ssh, const char *password) |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 193 | { |
djm@openbsd.org | 7c85685 | 2018-03-03 03:15:51 +0000 | [diff] [blame] | 194 | Authctxt *authctxt = ssh->authctxt; |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 195 | struct passwd *pw = authctxt->pw; |
Darren Tucker | 9286875 | 2016-07-15 13:32:45 +1000 | [diff] [blame] | 196 | char *encrypted_password, *salt = NULL; |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 197 | |
Damien Miller | 856f0be | 2003-09-03 07:32:45 +1000 | [diff] [blame] | 198 | /* Just use the supplied fake password if authctxt is invalid */ |
| 199 | char *pw_password = authctxt->valid ? shadow_pw(pw) : pw->pw_passwd; |
Damien Miller | 8a1e6a6 | 2000-09-16 15:55:52 +1100 | [diff] [blame] | 200 | |
Damien Miller | c29b111 | 2018-10-11 11:29:35 +1100 | [diff] [blame] | 201 | if (pw_password == NULL) |
| 202 | return 0; |
| 203 | |
Damien Miller | 8a1e6a6 | 2000-09-16 15:55:52 +1100 | [diff] [blame] | 204 | /* Check for users with no password. */ |
Damien Miller | 5d07e6d | 2003-09-18 18:25:46 +1000 | [diff] [blame] | 205 | if (strcmp(pw_password, "") == 0 && strcmp(password, "") == 0) |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 206 | return (1); |
Damien Miller | 2e1b082 | 1999-12-25 10:11:29 +1100 | [diff] [blame] | 207 | |
Darren Tucker | 9286875 | 2016-07-15 13:32:45 +1000 | [diff] [blame] | 208 | /* |
| 209 | * Encrypt the candidate password using the proper salt, or pass a |
| 210 | * NULL and let xcrypt pick one. |
| 211 | */ |
| 212 | if (authctxt->valid && pw_password[0] && pw_password[1]) |
| 213 | salt = pw_password; |
| 214 | encrypted_password = xcrypt(password, salt); |
Damien Miller | 2e1b082 | 1999-12-25 10:11:29 +1100 | [diff] [blame] | 215 | |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 216 | /* |
| 217 | * Authentication is accepted if the encrypted passwords |
| 218 | * are identical. |
| 219 | */ |
Damien Miller | 7584cb1 | 2012-04-26 09:51:26 +1000 | [diff] [blame] | 220 | return encrypted_password != NULL && |
| 221 | strcmp(encrypted_password, pw_password) == 0; |
Kevin Steves | e683e76 | 2002-04-04 19:02:28 +0000 | [diff] [blame] | 222 | } |
Darren Tucker | 23bc8d0 | 2004-02-06 16:24:31 +1100 | [diff] [blame] | 223 | #endif |