lib/libpam/modules/pam_lastlog/pam_lastlog.c

   1 /*      $NetBSD: pam_lastlog.c,v 1.12 2006/11/03 18:55:40 christos Exp $        */
   2
   3 /*-
   4  * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  * Copyright (c) 2001 Mark R V Murray
   7  * All rights reserved.
   8  * Copyright (c) 2001 Networks Associates Technology, Inc.
   9  * All rights reserved.
  10  * Copyright (c) 2004 Joe R. Doupnik
  11  * All rights reserved.
  12  *
  13  * Portions of this software were developed for the FreeBSD Project by
  14  * ThinkSec AS and NAI Labs, the Security Research Division of Network
  15  * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
  16  * ("CBOSS"), as part of the DARPA CHATS research program.
  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  * 3. The name of the author may not be used to endorse or promote
  27  *    products derived from this software without specific prior written
  28  *    permission.
  29  * 4. Neither the name of the University nor the names of its contributors
  30  *    may be used to endorse or promote products derived from this software
  31  *    without specific prior written permission.
  32  *
  33  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  34  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  35  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  36  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  37  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  38  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  39  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  41  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  42  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  43  * SUCH DAMAGE.
  44  */
  45
  46 #include <sys/cdefs.h>
  47 #ifdef __FreeBSD__
  48 __FBSDID("$FreeBSD: src/lib/libpam/modules/pam_lastlog/pam_lastlog.c,v 1.20 2004/01/26 19:28:37 des Exp $");
  49 #else
  50 __RCSID("$NetBSD: pam_lastlog.c,v 1.12 2006/11/03 18:55:40 christos Exp $");
  51 #endif
  52
  53 #include <sys/param.h>
  54
  55 #include <fcntl.h>
  56 #include <util.h>
  57 #include <paths.h>
  58 #include <pwd.h>
  59 #include <stdio.h>
  60 #include <stdlib.h>
  61 #include <string.h>
  62 #include <syslog.h>
  63 #include <time.h>
  64 #include <unistd.h>
  65 #include <stdarg.h>
  66 #ifdef LOGIN_CAP
  67 #include <login_cap.h>
  68 #endif
  69
  70 #define PAM_SM_SESSION
  71
  72 #include <security/pam_appl.h>
  73 #include <security/pam_modules.h>
  74 #include <security/pam_mod_misc.h>
  75
  76 #ifdef SUPPORT_UTMP
  77 #include <utmp.h>
  78 static void doutmp(const char *, const char *, const char *,
  79     const struct timeval *);
  80 static void dolastlog(pam_handle_t *, int, const struct passwd *, const char *,
  81     const char *, const struct timeval *);
  82 #endif
  83
  84 #ifdef SUPPORT_UTMPX
  85 #include <utmpx.h>
  86 static void doutmpx(const char *, const char *, const char *,
  87     const struct sockaddr_storage *ss, const struct timeval *);
  88 static void dolastlogx(pam_handle_t *, int, const struct passwd *, const char *,
  89     const char *, const struct sockaddr_storage *ss, const struct timeval *);
  90 #endif
  91
  92 #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
  93 static void domsg(pam_handle_t *, time_t, const char *, size_t, const char *,
  94     size_t);
  95 #endif
  96
  97 static void
  98 logit(int level, const char *fmt, ...)
  99 {
 100         va_list ap;
 101         struct syslog_data data = SYSLOG_DATA_INIT;
 102
 103         openlog_r("pam_lastlog", LOG_PID, LOG_AUTHPRIV, &data);
 104         va_start(ap, fmt);
 105         vsyslog_r(level, &data, fmt, ap);
 106         va_end(ap);
 107         closelog_r(&data);
 108 }
 109
 110
 111 PAM_EXTERN int
 112 pam_sm_open_session(pam_handle_t *pamh, int flags,
 113     int argc __unused, const char *argv[] __unused)
 114 {
 115         struct passwd *pwd, pwres;
 116         struct timeval now;
 117         const char *user, *rhost, *tty, *nuser;
 118         const void *vrhost, *vtty, *vss, *vnuser;
 119         const struct sockaddr_storage *ss;
 120         int pam_err;
 121         char pwbuf[1024];
 122 #ifdef LOGIN_CAP
 123         login_cap_t *lc;
 124 #endif
 125
 126         pam_err = pam_get_user(pamh, &user, NULL);
 127         if (pam_err != PAM_SUCCESS)
 128                 return pam_err;
 129
 130         if (user == NULL ||
 131             getpwnam_r(user, &pwres, pwbuf, sizeof(pwbuf), &pwd) != 0 ||
 132             pwd == NULL)
 133                 return PAM_SERVICE_ERR;
 134
 135         PAM_LOG("Got user: %s", user);
 136
 137         pam_err = pam_get_item(pamh, PAM_RHOST, &vrhost);
 138         if (pam_err != PAM_SUCCESS)
 139                 goto err;
 140         rhost = (const char *)vrhost;
 141
 142         pam_err = pam_get_item(pamh, PAM_SOCKADDR, &vss);
 143         if (pam_err != PAM_SUCCESS)
 144                 goto err;
 145         ss = (const struct sockaddr_storage *)vss;
 146
 147         pam_err = pam_get_item(pamh, PAM_TTY, &vtty);
 148         if (pam_err != PAM_SUCCESS)
 149                 goto err;
 150         tty = (const char *)vtty;
 151
 152         if (tty == NULL) {
 153                 pam_err = PAM_SERVICE_ERR;
 154                 goto err;
 155         }
 156
 157         if (pam_get_item(pamh, PAM_NUSER, &vnuser) != PAM_SUCCESS)
 158                 nuser = NULL;
 159         else
 160                 nuser = (const char *)vnuser;
 161
 162         if (strncmp(tty, _PATH_DEV, strlen(_PATH_DEV)) == 0)
 163                 tty = tty + strlen(_PATH_DEV);
 164
 165         if (*tty == '\0') {
 166                 pam_err = PAM_SERVICE_ERR;
 167                 goto err;
 168         }
 169
 170         (void)gettimeofday(&now, NULL);
 171
 172         if (openpam_get_option(pamh, "no_nested") == NULL || nuser == NULL) {
 173                 int quiet;
 174                 if ((flags & PAM_SILENT) != 0)
 175                         quiet = 1;
 176                 else {
 177 #ifdef LOGIN_CAP
 178                         lc = login_getpwclass(pwd);
 179                         quiet = login_getcapbool(lc, "hushlogin", 0);
 180                         login_close(lc);
 181 #else
 182                         quiet = 0;
 183 #endif
 184                 }
 185 #ifdef SUPPORT_UTMPX
 186                 doutmpx(user, rhost, tty, ss, &now);
 187                 dolastlogx(pamh, quiet, pwd, rhost, tty, ss, &now);
 188                 quiet = 1;
 189 #endif
 190 #ifdef SUPPORT_UTMP
 191                 doutmp(user, rhost, tty, &now);
 192                 dolastlog(pamh, quiet, pwd, rhost, tty, &now);
 193 #endif
 194         }
 195 err:
 196         if (openpam_get_option(pamh, "no_fail"))
 197                 return PAM_SUCCESS;
 198         return pam_err;
 199 }
 200
 201 PAM_EXTERN int
 202 pam_sm_close_session(pam_handle_t *pamh __unused, int flags __unused,
 203     int argc __unused, const char *argv[] __unused)
 204 {
 205         const void *vtty, *vnuser;
 206         const char *tty, *nuser;
 207
 208         if (pam_get_item(pamh, PAM_NUSER, &vnuser) != PAM_SUCCESS)
 209                 nuser = NULL;
 210         else
 211                 nuser = (const char *)vnuser;
 212
 213         pam_get_item(pamh, PAM_TTY, &vtty);
 214         if (vtty == NULL)
 215                 return PAM_SERVICE_ERR;
 216         tty = (const char *)vtty;
 217
 218         if (strncmp(tty, _PATH_DEV, strlen(_PATH_DEV)) == 0)
 219                 tty = tty + strlen(_PATH_DEV);
 220
 221         if (*tty == '\0')
 222                 return PAM_SERVICE_ERR;
 223
 224         if (openpam_get_option(pamh, "no_nested") == NULL || nuser == NULL) {
 225
 226 #ifdef SUPPORT_UTMPX
 227                 if (logoutx(tty, 0, DEAD_PROCESS))
 228                         logwtmpx(tty, "", "", 0, DEAD_PROCESS);
 229                 else
 230                         logit(LOG_NOTICE, "%s(): no utmpx record for %s",
 231                             __func__, tty);
 232 #endif
 233
 234 #ifdef SUPPORT_UTMP
 235                 if (logout(tty))
 236                         logwtmp(tty, "", "");
 237                 else
 238                         logit(LOG_NOTICE, "%s(): no utmp record for %s",
 239                             __func__, tty);
 240 #endif
 241         }
 242         return PAM_SUCCESS;
 243 }
 244
 245 #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
 246 static void
 247 domsg(pam_handle_t *pamh, time_t t, const char *host, size_t hsize,
 248     const char *line, size_t lsize)
 249 {
 250         char buf[MAXHOSTNAMELEN + 32], *promptresp = NULL;
 251         int pam_err;
 252
 253         if (*host) {
 254                 (void)snprintf(buf, sizeof(buf), "from %.*s ",
 255                     (int)hsize, host);
 256                 host = buf;
 257         }
 258
 259         pam_err = pam_prompt(pamh, PAM_TEXT_INFO, &promptresp,
 260             "Last login: %.24s %son %.*s\n", ctime(&t), host, (int)lsize, line);
 261
 262         if (pam_err == PAM_SUCCESS && promptresp)
 263                 free(promptresp);
 264 }
 265 #endif
 266
 267 #ifdef SUPPORT_UTMPX
 268 static void
 269 doutmpx(const char *username, const char *hostname, const char *tty,
 270     const struct sockaddr_storage *ss, const struct timeval *now)
 271 {
 272         struct utmpx utmpx;
 273         const char *t;
 274
 275         memset((void *)&utmpx, 0, sizeof(utmpx));
 276         utmpx.ut_tv = *now;
 277         (void)strncpy(utmpx.ut_name, username, sizeof(utmpx.ut_name));
 278         if (hostname) {
 279                 (void)strncpy(utmpx.ut_host, hostname, sizeof(utmpx.ut_host));
 280                 if (ss)
 281                         utmpx.ut_ss = *ss;
 282         }
 283         (void)strncpy(utmpx.ut_line, tty, sizeof(utmpx.ut_line));
 284         utmpx.ut_type = USER_PROCESS;
 285         utmpx.ut_pid = getpid();
 286         t = tty + strlen(tty);
 287         if ((size_t)(t - tty) >= sizeof(utmpx.ut_id)) {
 288                 (void)strncpy(utmpx.ut_id, t - sizeof(utmpx.ut_id),
 289                     sizeof(utmpx.ut_id));
 290         } else {
 291                 (void)strncpy(utmpx.ut_id, tty, sizeof(utmpx.ut_id));
 292         }
 293         if (pututxline(&utmpx) == NULL)
 294                 logit(LOG_NOTICE, "Cannot update utmpx %m");
 295         endutxent();
 296         if (updwtmpx(_PATH_WTMPX, &utmpx) != 0)
 297                 logit(LOG_NOTICE, "Cannot update wtmpx %m");
 298 }
 299
 300 static void
 301 dolastlogx(pam_handle_t *pamh, int quiet, const struct passwd *pwd,
 302     const char *hostname, const char *tty, const struct sockaddr_storage *ss,
 303     const struct timeval *now)
 304 {
 305         struct lastlogx ll;
 306         if (!quiet) {
 307             if (getlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != NULL)
 308                     domsg(pamh, (time_t)ll.ll_tv.tv_sec, ll.ll_host,
 309                         sizeof(ll.ll_host), ll.ll_line,
 310                         sizeof(ll.ll_line));
 311         }
 312         ll.ll_tv = *now;
 313         (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
 314
 315         if (hostname)
 316                 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
 317         else
 318                 (void)memset(ll.ll_host, 0, sizeof(ll.ll_host));
 319
 320         if (ss)
 321                 ll.ll_ss = *ss;
 322         else
 323                 (void)memset(&ll.ll_ss, 0, sizeof(ll.ll_ss));
 324
 325         if (updlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != 0)
 326                 logit(LOG_NOTICE, "Cannot update lastlogx %m");
 327         PAM_LOG("Login recorded in %s", _PATH_LASTLOGX);
 328 }
 329 #endif
 330
 331 #ifdef SUPPORT_UTMP
 332 static void
 333 doutmp(const char *username, const char *hostname, const char *tty,
 334     const struct timeval *now)
 335 {
 336         struct utmp utmp;
 337
 338         (void)memset((void *)&utmp, 0, sizeof(utmp));
 339         utmp.ut_time = now->tv_sec;
 340         (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name));
 341         if (hostname)
 342                 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host));
 343         (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
 344         login(&utmp);
 345 }
 346
 347 static void
 348 dolastlog(pam_handle_t *pamh, int quiet, const struct passwd *pwd,
 349     const char *hostname, const char *tty, const struct timeval *now)
 350 {
 351         struct lastlog ll;
 352         int fd;
 353
 354         if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) == -1) {
 355                 logit(LOG_NOTICE, "Cannot open `%s' %m", _PATH_LASTLOG);
 356                 return;
 357         }
 358         (void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)), SEEK_SET);
 359
 360         if (!quiet) {
 361                 if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) &&
 362                     ll.ll_time != 0)
 363                         domsg(pamh, ll.ll_time, ll.ll_host,
 364                             sizeof(ll.ll_host), ll.ll_line,
 365                             sizeof(ll.ll_line));
 366                 (void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)), SEEK_SET);
 367         }
 368
 369         ll.ll_time = now->tv_sec;
 370         (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
 371
 372         if (hostname)
 373                 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
 374         else
 375                 (void)memset(ll.ll_host, 0, sizeof(ll.ll_host));
 376
 377         (void)write(fd, &ll, sizeof(ll));
 378         (void)close(fd);
 379
 380         PAM_LOG("Login recorded in %s", _PATH_LASTLOG);
 381 }
 382 #endif
 383
 384 PAM_MODULE_ENTRY("pam_lastlog");