pam_lastlog.c revision 196650
1/*- 2 * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * Copyright (c) 2001 Mark R V Murray 5 * All rights reserved. 6 * Copyright (c) 2001 Networks Associates Technology, Inc. 7 * All rights reserved. 8 * Copyright (c) 2004 Joe R. Doupnik 9 * All rights reserved. 10 * 11 * Portions of this software were developed for the FreeBSD Project by 12 * ThinkSec AS and NAI Labs, the Security Research Division of Network 13 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 14 * ("CBOSS"), as part of the DARPA CHATS research program. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. The name of the author may not be used to endorse or promote 25 * products derived from this software without specific prior written 26 * permission. 27 * 4. Neither the name of the University nor the names of its contributors 28 * may be used to endorse or promote products derived from this software 29 * without specific prior written permission. 30 * 31 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 32 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 33 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 34 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 35 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 39 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 40 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 41 * SUCH DAMAGE. 42 */ 43 44#include <sys/cdefs.h> 45__FBSDID("$FreeBSD: head/lib/libpam/modules/pam_lastlog/pam_lastlog.c 196650 2009-08-30 05:12:37Z jon $"); 46 47#define _BSD_SOURCE 48 49#include <sys/param.h> 50 51#include <fcntl.h> 52#include <libutil.h> 53#include <paths.h> 54#include <pwd.h> 55#include <stdio.h> 56#include <stdlib.h> 57#include <string.h> 58#include <syslog.h> 59#include <time.h> 60#include <unistd.h> 61#include <utmp.h> 62 63#define PAM_SM_SESSION 64 65#include <security/pam_appl.h> 66#include <security/pam_modules.h> 67#include <security/pam_mod_misc.h> 68 69PAM_EXTERN int 70pam_sm_open_session(pam_handle_t *pamh, int flags, 71 int argc __unused, const char *argv[] __unused) 72{ 73 struct passwd *pwd; 74 struct utmp utmp; 75 struct lastlog ll; 76 time_t t; 77 const char *user; 78 const void *rhost, *tty; 79 off_t llpos; 80 int fd, pam_err; 81 82 pam_err = pam_get_user(pamh, &user, NULL); 83 if (pam_err != PAM_SUCCESS) 84 return (pam_err); 85 if (user == NULL || (pwd = getpwnam(user)) == NULL) 86 return (PAM_SERVICE_ERR); 87 PAM_LOG("Got user: %s", user); 88 89 pam_err = pam_get_item(pamh, PAM_RHOST, &rhost); 90 if (pam_err != PAM_SUCCESS) { 91 PAM_LOG("No PAM_RHOST"); 92 goto err; 93 } 94 pam_err = pam_get_item(pamh, PAM_TTY, &tty); 95 if (pam_err != PAM_SUCCESS) { 96 PAM_LOG("No PAM_TTY"); 97 goto err; 98 } 99 if (tty == NULL) { 100 PAM_LOG("No PAM_TTY"); 101 pam_err = PAM_SERVICE_ERR; 102 goto err; 103 } 104 if (strncmp(tty, _PATH_DEV, strlen(_PATH_DEV)) == 0) 105 tty = (const char *)tty + strlen(_PATH_DEV); 106 if (*(const char *)tty == '\0') 107 return (PAM_SERVICE_ERR); 108 109 fd = open(_PATH_LASTLOG, O_RDWR|O_CREAT, 0644); 110 if (fd == -1) { 111 PAM_LOG("Failed to open %s", _PATH_LASTLOG); 112 goto file_err; 113 } 114 115 /* 116 * Record session in lastlog(5). 117 */ 118 llpos = (off_t)(pwd->pw_uid * sizeof(ll)); 119 if (lseek(fd, llpos, L_SET) != llpos) 120 goto file_err; 121 if ((flags & PAM_SILENT) == 0) { 122 if (read(fd, &ll, sizeof ll) == sizeof ll && ll.ll_time != 0) { 123 t = ll.ll_time; 124 if (*ll.ll_host != '\0') 125 pam_info(pamh, "Last login: %.*s from %.*s", 126 24 - 5, ctime(&t), 127 (int)sizeof(ll.ll_host), ll.ll_host); 128 else 129 pam_info(pamh, "Last login: %.*s on %.*s", 130 24 - 5, ctime(&t), 131 (int)sizeof(ll.ll_line), ll.ll_line); 132 } 133 if (lseek(fd, llpos, L_SET) != llpos) 134 goto file_err; 135 } 136 137 bzero(&ll, sizeof(ll)); 138 ll.ll_time = time(NULL); 139 140 /* note: does not need to be NUL-terminated */ 141 strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 142 if (rhost != NULL && *(const char *)rhost != '\0') 143 /* note: does not need to be NUL-terminated */ 144 strncpy(ll.ll_host, rhost, sizeof(ll.ll_host)); 145 146 if (write(fd, (char *)&ll, sizeof(ll)) != sizeof(ll) || close(fd) != 0) 147 goto file_err; 148 149 PAM_LOG("Login recorded in %s", _PATH_LASTLOG); 150 151 /* 152 * Record session in utmp(5) and wtmp(5). 153 */ 154 bzero(&utmp, sizeof(utmp)); 155 utmp.ut_time = time(NULL); 156 /* note: does not need to be NUL-terminated */ 157 strncpy(utmp.ut_name, user, sizeof(utmp.ut_name)); 158 if (rhost != NULL && *(const char *)rhost != '\0') 159 strncpy(utmp.ut_host, rhost, sizeof(utmp.ut_host)); 160 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line)); 161 login(&utmp); 162 163 return (PAM_SUCCESS); 164 165file_err: 166 syslog(LOG_ERR, "%s: %m", _PATH_LASTLOG); 167 if (fd != -1) 168 close(fd); 169 pam_err = PAM_SYSTEM_ERR; 170err: 171 if (openpam_get_option(pamh, "no_fail")) 172 return (PAM_SUCCESS); 173 return (pam_err); 174} 175 176PAM_EXTERN int 177pam_sm_close_session(pam_handle_t *pamh __unused, int flags __unused, 178 int argc __unused, const char *argv[] __unused) 179{ 180 const void *tty; 181 int pam_err; 182 183 pam_err = pam_get_item(pamh, PAM_TTY, (const void **)&tty); 184 if (pam_err != PAM_SUCCESS) 185 goto err; 186 if (tty == NULL) { 187 PAM_LOG("No PAM_TTY"); 188 pam_err = PAM_SERVICE_ERR; 189 goto err; 190 } 191 if (strncmp(tty, _PATH_DEV, strlen(_PATH_DEV)) == 0) 192 tty = (const char *)tty + strlen(_PATH_DEV); 193 if (*(const char *)tty == '\0') 194 return (PAM_SERVICE_ERR); 195 if (logout(tty) != 1) 196 syslog(LOG_ERR, "%s(): no utmp record for %s", 197 __func__, (const char *)tty); 198 logwtmp(tty, "", ""); 199 return (PAM_SUCCESS); 200 201 err: 202 if (openpam_get_option(pamh, "no_fail")) 203 return (PAM_SUCCESS); 204 return (pam_err); 205} 206 207PAM_MODULE_ENTRY("pam_lastlog"); 208