usr.bin/last/last.c

   1 /*
   2  * Copyright (c) 1987, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #ifndef lint
  31 static const char copyright[] =
  32 "@(#) Copyright (c) 1987, 1993, 1994\n\
  33         The Regents of the University of California.  All rights reserved.\n";
  34 #endif /* not lint */
  35
  36 #ifndef lint
  37 static const char sccsid[] = "@(#)last.c        8.2 (Berkeley) 4/2/94";
  38 #endif /* not lint */
  39 #include <sys/cdefs.h>
  40 __FBSDID("$FreeBSD$");
  41
  42 #include <sys/param.h>
  43 #include <sys/stat.h>
  44
  45 #include <err.h>
  46 #include <errno.h>
  47 #include <fcntl.h>
  48 #include <langinfo.h>
  49 #include <locale.h>
  50 #include <paths.h>
  51 #include <signal.h>
  52 #include <stdio.h>
  53 #include <stdlib.h>
  54 #include <string.h>
  55 #include <time.h>
  56 #include <timeconv.h>
  57 #include <unistd.h>
  58 #include <utmpx.h>
  59 #include <sys/queue.h>
  60
  61 #define NO      0                               /* false/no */
  62 #define YES     1                               /* true/yes */
  63 #define ATOI2(ar)       ((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
  64
  65 typedef struct arg {
  66         char    *name;                          /* argument */
  67 #define REBOOT_TYPE     -1
  68 #define HOST_TYPE       -2
  69 #define TTY_TYPE        -3
  70 #define USER_TYPE       -4
  71         int     type;                           /* type of arg */
  72         struct arg      *next;                  /* linked list pointer */
  73 } ARG;
  74 static ARG      *arglist;                       /* head of linked list */
  75
  76 static SLIST_HEAD(, idtab) idlist;
  77
  78 struct idtab {
  79         time_t  logout;                         /* log out time */
  80         char    id[sizeof ((struct utmpx *)0)->ut_id]; /* identifier */
  81         SLIST_ENTRY(idtab) list;
  82 };
  83
  84 static const    char *crmsg;                    /* cause of last reboot */
  85 static time_t   currentout;                     /* current logout value */
  86 static long     maxrec;                         /* records to display */
  87 static const    char *file = NULL;              /* utx.log file */
  88 static int      sflag = 0;                      /* show delta in seconds */
  89 static int      width = 5;                      /* show seconds in delta */
  90 static int      yflag;                          /* show year */
  91 static int      d_first;
  92 static int      snapfound = 0;                  /* found snapshot entry? */
  93 static time_t   snaptime;                       /* if != 0, we will only
  94                                                  * report users logged in
  95                                                  * at this snapshot time
  96                                                  */
  97
  98 static void      addarg(int, char *);
  99 static time_t    dateconv(char *);
 100 static void      doentry(struct utmpx *);
 101 static void      hostconv(char *);
 102 static void      printentry(struct utmpx *, struct idtab *);
 103 static char     *ttyconv(char *);
 104 static int       want(struct utmpx *);
 105 static void      usage(void);
 106 static void      wtmp(void);
 107
 108 static void
 109 usage(void)
 110 {
 111         (void)fprintf(stderr,
 112 "usage: last [-swy] [-d [[CC]YY][MMDD]hhmm[.SS]] [-f file] [-h host]\n"
 113 "            [-n maxrec] [-t tty] [user ...]\n");
 114         exit(1);
 115 }
 116
 117 int
 118 main(int argc, char *argv[])
 119 {
 120         int ch;
 121         char *p;
 122
 123         (void) setlocale(LC_TIME, "");
 124         d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
 125
 126         maxrec = -1;
 127         snaptime = 0;
 128         while ((ch = getopt(argc, argv, "0123456789d:f:h:n:st:wy")) != -1)
 129                 switch (ch) {
 130                 case '0': case '1': case '2': case '3': case '4':
 131                 case '5': case '6': case '7': case '8': case '9':
 132                         /*
 133                          * kludge: last was originally designed to take
 134                          * a number after a dash.
 135                          */
 136                         if (maxrec == -1) {
 137                                 p = strchr(argv[optind - 1], ch);
 138                                 if (p == NULL)
 139                                         p = strchr(argv[optind], ch);
 140                                 maxrec = atol(p);
 141                                 if (!maxrec)
 142                                         exit(0);
 143                         }
 144                         break;
 145                 case 'd':
 146                         snaptime = dateconv(optarg);
 147                         break;
 148                 case 'f':
 149                         file = optarg;
 150                         break;
 151                 case 'h':
 152                         hostconv(optarg);
 153                         addarg(HOST_TYPE, optarg);
 154                         break;
 155                 case 'n':
 156                         errno = 0;
 157                         maxrec = strtol(optarg, &p, 10);
 158                         if (p == optarg || *p != '\0' || errno != 0 ||
 159                             maxrec <= 0)
 160                                 errx(1, "%s: bad line count", optarg);
 161                         break;
 162                 case 's':
 163                         sflag++;        /* Show delta as seconds */
 164                         break;
 165                 case 't':
 166                         addarg(TTY_TYPE, ttyconv(optarg));
 167                         break;
 168                 case 'w':
 169                         width = 8;
 170                         break;
 171                 case 'y':
 172                         yflag++;
 173                         break;
 174                 case '?':
 175                 default:
 176                         usage();
 177                 }
 178
 179         if (sflag && width == 8) usage();
 180
 181         if (argc) {
 182                 setlinebuf(stdout);
 183                 for (argv += optind; *argv; ++argv) {
 184                         if (strcmp(*argv, "reboot") == 0)
 185                                 addarg(REBOOT_TYPE, *argv);
 186 #define COMPATIBILITY
 187 #ifdef  COMPATIBILITY
 188                         /* code to allow "last p5" to work */
 189                         addarg(TTY_TYPE, ttyconv(*argv));
 190 #endif
 191                         addarg(USER_TYPE, *argv);
 192                 }
 193         }
 194         wtmp();
 195         exit(0);
 196 }
 197
 198 /*
 199  * wtmp --
 200  *      read through the utx.log file
 201  */
 202 static void
 203 wtmp(void)
 204 {
 205         struct utmpx *buf = NULL;
 206         struct utmpx *ut;
 207         static unsigned int amount = 0;
 208         time_t t;
 209         char ct[80];
 210         struct tm *tm;
 211
 212         SLIST_INIT(&idlist);
 213         (void)time(&t);
 214
 215         /* Load the last entries from the file. */
 216         if (setutxdb(UTXDB_LOG, file) != 0)
 217                 err(1, "%s", file);
 218         while ((ut = getutxent()) != NULL) {
 219                 if (amount % 128 == 0) {
 220                         buf = realloc(buf, (amount + 128) * sizeof *ut);
 221                         if (buf == NULL)
 222                                 err(1, "realloc");
 223                 }
 224                 memcpy(&buf[amount++], ut, sizeof *ut);
 225                 if (t > ut->ut_tv.tv_sec)
 226                         t = ut->ut_tv.tv_sec;
 227         }
 228         endutxent();
 229
 230         /* Display them in reverse order. */
 231         while (amount > 0)
 232                 doentry(&buf[--amount]);
 233
 234         tm = localtime(&t);
 235         (void) strftime(ct, sizeof(ct), "%+", tm);
 236         printf("\n%s begins %s\n", ((file == NULL) ? "utx.log" : file), ct);
 237 }
 238
 239 /*
 240  * doentry --
 241  *      process a single utx.log entry
 242  */
 243 static void
 244 doentry(struct utmpx *bp)
 245 {
 246         struct idtab *tt;
 247
 248         /* the machine stopped */
 249         if (bp->ut_type == BOOT_TIME || bp->ut_type == SHUTDOWN_TIME) {
 250                 /* everybody just logged out */
 251                 while ((tt = SLIST_FIRST(&idlist)) != NULL) {
 252                         SLIST_REMOVE_HEAD(&idlist, list);
 253                         free(tt);
 254                 }
 255                 currentout = -bp->ut_tv.tv_sec;
 256                 crmsg = bp->ut_type != SHUTDOWN_TIME ?
 257                     "crash" : "shutdown";
 258                 /*
 259                  * if we're in snapshot mode, we want to exit if this
 260                  * shutdown/reboot appears while we we are tracking the
 261                  * active range
 262                  */
 263                 if (snaptime && snapfound)
 264                         exit(0);
 265                 /*
 266                  * don't print shutdown/reboot entries unless flagged for
 267                  */
 268                 if (!snaptime && want(bp))
 269                         printentry(bp, NULL);
 270                 return;
 271         }
 272         /* date got set */
 273         if (bp->ut_type == OLD_TIME || bp->ut_type == NEW_TIME) {
 274                 if (want(bp) && !snaptime)
 275                         printentry(bp, NULL);
 276                 return;
 277         }
 278
 279         if (bp->ut_type != USER_PROCESS && bp->ut_type != DEAD_PROCESS)
 280                 return;
 281
 282         /* find associated identifier */
 283         SLIST_FOREACH(tt, &idlist, list)
 284             if (!memcmp(tt->id, bp->ut_id, sizeof bp->ut_id))
 285                     break;
 286
 287         if (tt == NULL) {
 288                 /* add new one */
 289                 tt = malloc(sizeof(struct idtab));
 290                 if (tt == NULL)
 291                         errx(1, "malloc failure");
 292                 tt->logout = currentout;
 293                 memcpy(tt->id, bp->ut_id, sizeof bp->ut_id);
 294                 SLIST_INSERT_HEAD(&idlist, tt, list);
 295         }
 296
 297         /*
 298          * print record if not in snapshot mode and wanted
 299          * or in snapshot mode and in snapshot range
 300          */
 301         if (bp->ut_type == USER_PROCESS && (want(bp) ||
 302             (bp->ut_tv.tv_sec < snaptime &&
 303             (tt->logout > snaptime || tt->logout < 1)))) {
 304                 snapfound = 1;
 305                 printentry(bp, tt);
 306         }
 307         tt->logout = bp->ut_tv.tv_sec;
 308 }
 309
 310 /*
 311  * printentry --
 312  *      output an entry
 313  *
 314  * If `tt' is non-NULL, use it and `crmsg' to print the logout time or
 315  * logout type (crash/shutdown) as appropriate.
 316  */
 317 static void
 318 printentry(struct utmpx *bp, struct idtab *tt)
 319 {
 320         char ct[80];
 321         struct tm *tm;
 322         time_t  delta;                          /* time difference */
 323         time_t  t;
 324
 325         if (maxrec != -1 && !maxrec--)
 326                 exit(0);
 327         t = bp->ut_tv.tv_sec;
 328         tm = localtime(&t);
 329         (void) strftime(ct, sizeof(ct), d_first ?
 330             (yflag ? "%a %e %b %Y %R" : "%a %e %b %R") :
 331             (yflag ? "%a %b %e %Y %R" : "%a %b %e %R"), tm);
 332         switch (bp->ut_type) {
 333         case BOOT_TIME:
 334                 printf("%-42s", "boot time");
 335                 break;
 336         case SHUTDOWN_TIME:
 337                 printf("%-42s", "shutdown time");
 338                 break;
 339         case OLD_TIME:
 340                 printf("%-42s", "old time");
 341                 break;
 342         case NEW_TIME:
 343                 printf("%-42s", "new time");
 344                 break;
 345         case USER_PROCESS:
 346                 printf("%-10s %-8s %-22.22s",
 347                     bp->ut_user, bp->ut_line, bp->ut_host);
 348                 break;
 349         }
 350         printf(" %s%c", ct, tt == NULL ? '\n' : ' ');
 351         if (tt == NULL)
 352                 return;
 353         if (!tt->logout) {
 354                 puts("  still logged in");
 355                 return;
 356         }
 357         if (tt->logout < 0) {
 358                 tt->logout = -tt->logout;
 359                 printf("- %s", crmsg);
 360         } else {
 361                 tm = localtime(&tt->logout);
 362                 (void) strftime(ct, sizeof(ct), "%R", tm);
 363                 printf("- %s", ct);
 364         }
 365         delta = tt->logout - bp->ut_tv.tv_sec;
 366         if (sflag) {
 367                 printf("  (%8ld)\n", (long)delta);
 368         } else {
 369                 tm = gmtime(&delta);
 370                 (void) strftime(ct, sizeof(ct), width >= 8 ? "%T" : "%R", tm);
 371                 if (delta < 86400)
 372                         printf("  (%s)\n", ct);
 373                 else
 374                         printf(" (%ld+%s)\n", (long)delta / 86400, ct);
 375         }
 376 }
 377
 378 /*
 379  * want --
 380  *      see if want this entry
 381  */
 382 static int
 383 want(struct utmpx *bp)
 384 {
 385         ARG *step;
 386
 387         if (snaptime)
 388                 return (NO);
 389
 390         if (!arglist)
 391                 return (YES);
 392
 393         for (step = arglist; step; step = step->next)
 394                 switch(step->type) {
 395                 case REBOOT_TYPE:
 396                         if (bp->ut_type == BOOT_TIME ||
 397                             bp->ut_type == SHUTDOWN_TIME)
 398                                 return (YES);
 399                         break;
 400                 case HOST_TYPE:
 401                         if (!strcasecmp(step->name, bp->ut_host))
 402                                 return (YES);
 403                         break;
 404                 case TTY_TYPE:
 405                         if (!strcmp(step->name, bp->ut_line))
 406                                 return (YES);
 407                         break;
 408                 case USER_TYPE:
 409                         if (!strcmp(step->name, bp->ut_user))
 410                                 return (YES);
 411                         break;
 412                 }
 413         return (NO);
 414 }
 415
 416 /*
 417  * addarg --
 418  *      add an entry to a linked list of arguments
 419  */
 420 static void
 421 addarg(int type, char *arg)
 422 {
 423         ARG *cur;
 424
 425         if ((cur = malloc(sizeof(ARG))) == NULL)
 426                 errx(1, "malloc failure");
 427         cur->next = arglist;
 428         cur->type = type;
 429         cur->name = arg;
 430         arglist = cur;
 431 }
 432
 433 /*
 434  * hostconv --
 435  *      convert the hostname to search pattern; if the supplied host name
 436  *      has a domain attached that is the same as the current domain, rip
 437  *      off the domain suffix since that's what login(1) does.
 438  */
 439 static void
 440 hostconv(char *arg)
 441 {
 442         static int first = 1;
 443         static char *hostdot, name[MAXHOSTNAMELEN];
 444         char *argdot;
 445
 446         if (!(argdot = strchr(arg, '.')))
 447                 return;
 448         if (first) {
 449                 first = 0;
 450                 if (gethostname(name, sizeof(name)))
 451                         err(1, "gethostname");
 452                 hostdot = strchr(name, '.');
 453         }
 454         if (hostdot && !strcasecmp(hostdot, argdot))
 455                 *argdot = '\0';
 456 }
 457
 458 /*
 459  * ttyconv --
 460  *      convert tty to correct name.
 461  */
 462 static char *
 463 ttyconv(char *arg)
 464 {
 465         char *mval;
 466
 467         /*
 468          * kludge -- we assume that all tty's end with
 469          * a two character suffix.
 470          */
 471         if (strlen(arg) == 2) {
 472                 /* either 6 for "ttyxx" or 8 for "console" */
 473                 if ((mval = malloc(8)) == NULL)
 474                         errx(1, "malloc failure");
 475                 if (!strcmp(arg, "co"))
 476                         (void)strcpy(mval, "console");
 477                 else {
 478                         (void)strcpy(mval, "tty");
 479                         (void)strcpy(mval + 3, arg);
 480                 }
 481                 return (mval);
 482         }
 483         if (!strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1))
 484                 return (arg + 5);
 485         return (arg);
 486 }
 487
 488 /*
 489  * dateconv --
 490  *      Convert the snapshot time in command line given in the format
 491  *      [[CC]YY]MMDDhhmm[.SS]] to a time_t.
 492  *      Derived from atime_arg1() in usr.bin/touch/touch.c
 493  */
 494 static time_t
 495 dateconv(char *arg)
 496 {
 497         time_t timet;
 498         struct tm *t;
 499         int yearset;
 500         char *p;
 501
 502         /* Start with the current time. */
 503         if (time(&timet) < 0)
 504                 err(1, "time");
 505         if ((t = localtime(&timet)) == NULL)
 506                 err(1, "localtime");
 507
 508         /* [[CC]YY]MMDDhhmm[.SS] */
 509         if ((p = strchr(arg, '.')) == NULL)
 510                 t->tm_sec = 0;          /* Seconds defaults to 0. */
 511         else {
 512                 if (strlen(p + 1) != 2)
 513                         goto terr;
 514                 *p++ = '\0';
 515                 t->tm_sec = ATOI2(p);
 516         }
 517
 518         yearset = 0;
 519         switch (strlen(arg)) {
 520         case 12:                        /* CCYYMMDDhhmm */
 521                 t->tm_year = ATOI2(arg);
 522                 t->tm_year *= 100;
 523                 yearset = 1;
 524                 /* FALLTHROUGH */
 525         case 10:                        /* YYMMDDhhmm */
 526                 if (yearset) {
 527                         yearset = ATOI2(arg);
 528                         t->tm_year += yearset;
 529                 } else {
 530                         yearset = ATOI2(arg);
 531                         if (yearset < 69)
 532                                 t->tm_year = yearset + 2000;
 533                         else
 534                                 t->tm_year = yearset + 1900;
 535                 }
 536                 t->tm_year -= 1900;     /* Convert to UNIX time. */
 537                 /* FALLTHROUGH */
 538         case 8:                         /* MMDDhhmm */
 539                 t->tm_mon = ATOI2(arg);
 540                 --t->tm_mon;            /* Convert from 01-12 to 00-11 */
 541                 t->tm_mday = ATOI2(arg);
 542                 t->tm_hour = ATOI2(arg);
 543                 t->tm_min = ATOI2(arg);
 544                 break;
 545         case 4:                         /* hhmm */
 546                 t->tm_hour = ATOI2(arg);
 547                 t->tm_min = ATOI2(arg);
 548                 break;
 549         default:
 550                 goto terr;
 551         }
 552         t->tm_isdst = -1;               /* Figure out DST. */
 553         timet = mktime(t);
 554         if (timet == -1)
 555 terr:           errx(1,
 556         "out of range or illegal time specification: [[CC]YY]MMDDhhmm[.SS]");
 557         return timet;
 558 }