1 /* $NetBSD: pam_group.c,v 1.9 2005/04/19 13:04:19 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2003 Networks Associates Technology, Inc. 5 * All rights reserved. 6 * 7 * Portions of this software were developed for the FreeBSD Project by 8 * ThinkSec AS and NAI Labs, the Security Research Division of Network 9 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 10 * ("CBOSS"), as part of the DARPA CHATS research program. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. The name of the author may not be used to endorse or promote 21 * products derived from this software without specific prior written 22 * permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 #ifdef __FreeBSD__ 39 __FBSDID("$FreeBSD: src/lib/libpam/modules/pam_group/pam_group.c,v 1.4 2003/12/11 13:55:15 des Exp $"); 40 #else 41 __RCSID("$NetBSD: pam_group.c,v 1.9 2005/04/19 13:04:19 christos Exp $"); 42 #endif 43 44 #include <sys/types.h> 45 46 #include <grp.h> 47 #include <pwd.h> 48 #include <stdarg.h> 49 #include <stdio.h> 50 #include <string.h> 51 #include <stdlib.h> 52 #include <syslog.h> 53 #include <unistd.h> 54 #include <login_cap.h> 55 56 #define PAM_SM_AUTH 57 58 #include <security/pam_appl.h> 59 #include <security/pam_modules.h> 60 #include <security/pam_mod_misc.h> 61 #include <security/openpam.h> 62 63 static int authenticate(pam_handle_t *, struct passwd *, int); 64 65 PAM_EXTERN int 66 pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 67 int argc __unused, const char *argv[] __unused) 68 { 69 const char *group, *user; 70 const void *ruser; 71 char *const *list; 72 struct passwd *pwd, pwres; 73 struct group *grp, grres; 74 int pam_err, auth; 75 char *promptresp = NULL; 76 char pwbuf[1024]; 77 char grbuf[1024]; 78 79 /* get target account */ 80 if (pam_get_user(pamh, &user, NULL) != PAM_SUCCESS || 81 user == NULL || 82 getpwnam_r(user, &pwres, pwbuf, sizeof(pwbuf), &pwd) != 0 || 83 pwd == NULL) 84 return (PAM_AUTH_ERR); 85 if (pwd->pw_uid != 0 && openpam_get_option(pamh, "root_only")) 86 return (PAM_IGNORE); 87 88 /* get applicant */ 89 if (pam_get_item(pamh, PAM_RUSER, &ruser) != PAM_SUCCESS || 90 ruser == NULL || 91 getpwnam_r(ruser, &pwres, pwbuf, sizeof(pwbuf), &pwd) != 0 || 92 pwd == NULL) 93 return (PAM_AUTH_ERR); 94 95 auth = openpam_get_option(pamh, "authenticate") != NULL; 96 97 /* get regulating group */ 98 if ((group = openpam_get_option(pamh, "group")) == NULL) 99 group = "wheel"; 100 if (getgrnam_r(group, &grres, grbuf, sizeof(grbuf), &grp) != 0 || 101 grp == NULL || grp->gr_mem == NULL) 102 goto failed; 103 104 /* check if the group is empty */ 105 if (*grp->gr_mem == NULL) 106 goto failed; 107 108 /* check membership */ 109 if (pwd->pw_gid == grp->gr_gid) 110 goto found; 111 for (list = grp->gr_mem; *list != NULL; ++list) 112 if (strcmp(*list, pwd->pw_name) == 0) 113 goto found; 114 115 not_found: 116 if (openpam_get_option(pamh, "deny")) 117 return (PAM_SUCCESS); 118 if (!auth) { 119 pam_err = pam_prompt(pamh, PAM_ERROR_MSG, &promptresp, 120 "%s: You are not listed in the correct secondary group" 121 " (%s) to %s %s.", getprogname(), group, getprogname(), 122 user); 123 if (pam_err == PAM_SUCCESS && promptresp) 124 free(promptresp); 125 } 126 return (PAM_AUTH_ERR); 127 found: 128 if (auth) 129 if ((pam_err = authenticate(pamh, pwd, flags)) != PAM_SUCCESS) 130 return pam_err; 131 132 if (openpam_get_option(pamh, "deny")) 133 return (PAM_AUTH_ERR); 134 return (PAM_SUCCESS); 135 failed: 136 if (openpam_get_option(pamh, "fail_safe")) 137 goto found; 138 else 139 goto not_found; 140 } 141 142 PAM_EXTERN int 143 pam_sm_setcred(pam_handle_t * pamh __unused, int flags __unused, 144 int argc __unused, const char *argv[] __unused) 145 { 146 147 return (PAM_SUCCESS); 148 } 149 150 static int 151 authenticate(pam_handle_t *pamh, struct passwd *pwd, int flags) 152 { 153 int retval; 154 login_cap_t *lc; 155 const char *pass; 156 157 lc = login_getpwclass(pwd); 158 retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, NULL); 159 login_close(lc); 160 161 if (retval != PAM_SUCCESS) 162 return retval; 163 PAM_LOG("Got password"); 164 if (strcmp(crypt(pass, pwd->pw_passwd), pwd->pw_passwd) == 0) 165 return PAM_SUCCESS; 166 167 PAM_VERBOSE_ERROR("UNIX authentication refused"); 168 return PAM_AUTH_ERR; 169 } 170 171 172 PAM_MODULE_ENTRY("pam_group"); 173