1/* $NetBSD: pam_group.c,v 1.11 2009/02/11 18:38:56 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 1.11 2009/02/11 18:38:56 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 <unistd.h> 53#include <login_cap.h> 54 55#define PAM_SM_AUTH 56 57#include <security/pam_appl.h> 58#include <security/pam_modules.h> 59#include <security/pam_mod_misc.h> 60#include <security/openpam.h> 61 62static int authenticate(pam_handle_t *, struct passwd *, int); 63 64#define PASSWORD_PROMPT "%s's password:" 65 66PAM_EXTERN int 67pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 68 int argc __unused, const char *argv[] __unused) 69{ 70 const char *group, *user; 71 const void *ruser; 72 char *const *list; 73 struct passwd *pwd, pwres; 74 struct group *grp, grres; 75 int pam_err, auth; 76 char *promptresp = NULL; 77 char pwbuf[1024]; 78 char grbuf[1024]; 79 80 /* get target account */ 81 if (pam_get_user(pamh, &user, NULL) != PAM_SUCCESS || 82 user == NULL || 83 getpwnam_r(user, &pwres, pwbuf, sizeof(pwbuf), &pwd) != 0 || 84 pwd == NULL) 85 return (PAM_AUTH_ERR); 86 if (pwd->pw_uid != 0 && openpam_get_option(pamh, "root_only")) 87 return (PAM_IGNORE); 88 89 /* get applicant */ 90 if (pam_get_item(pamh, PAM_RUSER, &ruser) != PAM_SUCCESS || 91 ruser == NULL || 92 getpwnam_r(ruser, &pwres, pwbuf, sizeof(pwbuf), &pwd) != 0 || 93 pwd == NULL) 94 return (PAM_AUTH_ERR); 95 96 auth = openpam_get_option(pamh, "authenticate") != NULL; 97 98 /* get regulating group */ 99 if ((group = openpam_get_option(pamh, "group")) == NULL) 100 group = "wheel"; 101 if (getgrnam_r(group, &grres, grbuf, sizeof(grbuf), &grp) != 0 || 102 grp == NULL || grp->gr_mem == NULL) 103 goto failed; 104 105 /* check if the group is empty */ 106 if (*grp->gr_mem == NULL) 107 goto failed; 108 109 /* check membership */ 110 if (pwd->pw_gid == grp->gr_gid) 111 goto found; 112 for (list = grp->gr_mem; *list != NULL; ++list) 113 if (strcmp(*list, pwd->pw_name) == 0) 114 goto found; 115 116 not_found: 117 if (openpam_get_option(pamh, "deny")) 118 return (PAM_SUCCESS); 119 if (!auth) { 120 pam_err = pam_prompt(pamh, PAM_ERROR_MSG, &promptresp, 121 "%s: You are not listed in the correct secondary group" 122 " (%s) to %s %s.", getprogname(), group, getprogname(), 123 user); 124 if (pam_err == PAM_SUCCESS && promptresp) 125 free(promptresp); 126 } 127 return (PAM_AUTH_ERR); 128 found: 129 if (auth) 130 if ((pam_err = authenticate(pamh, pwd, flags)) != PAM_SUCCESS) 131 return pam_err; 132 133 if (openpam_get_option(pamh, "deny")) 134 return (PAM_AUTH_ERR); 135 return (PAM_SUCCESS); 136 failed: 137 if (openpam_get_option(pamh, "fail_safe")) 138 goto found; 139 else 140 goto not_found; 141} 142 143PAM_EXTERN int 144pam_sm_setcred(pam_handle_t * pamh __unused, int flags __unused, 145 int argc __unused, const char *argv[] __unused) 146{ 147 148 return (PAM_SUCCESS); 149} 150 151static int 152authenticate(pam_handle_t *pamh, struct passwd *pwd, int flags) 153{ 154 int retval; 155 login_cap_t *lc; 156 const char *pass; 157 char password_prompt[80]; 158 159 (void) snprintf(password_prompt, sizeof(password_prompt), 160 PASSWORD_PROMPT, pwd->pw_name); 161 lc = login_getpwclass(pwd); 162 retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, password_prompt); 163 login_close(lc); 164 165 if (retval != PAM_SUCCESS) 166 return retval; 167 PAM_LOG("Got password"); 168 if (strcmp(crypt(pass, pwd->pw_passwd), pwd->pw_passwd) == 0) 169 return PAM_SUCCESS; 170 171 PAM_VERBOSE_ERROR("UNIX authentication refused"); 172 return PAM_AUTH_ERR; 173} 174 175 176PAM_MODULE_ENTRY("pam_group"); 177