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  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * $FreeBSD: src/usr.bin/last/last.c,v 1.10.6.11 2002/11/02 23:00:26 mux Exp $
  34  * $DragonFly: src/usr.bin/last/last.c,v 1.5 2004/09/14 00:13:36 drhodus Exp $
  35  *
  36  * @(#) Copyright (c) 1987, 1993, 1994 The Regents of the University of California.  All rights reserved.
  37  * @(#)last.c   8.2 (Berkeley) 4/2/94
  38  */
  39
  40 #include <sys/param.h>
  41 #include <sys/stat.h>
  42
  43 #include <err.h>
  44 #include <fcntl.h>
  45 #include <langinfo.h>
  46 #include <locale.h>
  47 #include <paths.h>
  48 #include <signal.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <time.h>
  53 #include <unistd.h>
  54 #include <utmp.h>
  55 #include <sys/queue.h>
  56
  57 #define NO      0                               /* false/no */
  58 #define YES     1                               /* true/yes */
  59 #define ATOI2(ar)       ((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
  60
  61 static struct utmp      buf[1024];              /* utmp read buffer */
  62
  63 typedef struct arg {
  64         char    *name;                          /* argument */
  65 #define HOST_TYPE       -2
  66 #define TTY_TYPE        -3
  67 #define USER_TYPE       -4
  68         int     type;                           /* type of arg */
  69         struct arg      *next;                  /* linked list pointer */
  70 } ARG;
  71 ARG     *arglist;                               /* head of linked list */
  72
  73 LIST_HEAD(ttylisthead, ttytab) ttylist;
  74
  75 struct ttytab {
  76         time_t  logout;                         /* log out time */
  77         char    tty[UT_LINESIZE + 1];           /* terminal name */
  78         LIST_ENTRY(ttytab) list;
  79 };
  80
  81 static const    char *crmsg;                    /* cause of last reboot */
  82 static long     currentout,                     /* current logout value */
  83                 maxrec;                         /* records to display */
  84 static const    char *file = _PATH_WTMP;                /* wtmp file */
  85 static int      sflag = 0;                      /* show delta in seconds */
  86 static int      width = 5;                      /* show seconds in delta */
  87 static int      yflag;                          /* show year */
  88 static int      d_first;
  89 static int      snapfound = 0;                  /* found snapshot entry? */
  90 static time_t   snaptime;                       /* if != 0, we will only
  91                                                  * report users logged in
  92                                                  * at this snapshot time
  93                                                  */
  94
  95 int      main(int, char *[]);
  96 void     addarg(int, char *);
  97 time_t   dateconv(char *);
  98 void     doentry(struct utmp *);
  99 void     hostconv(char *);
 100 void     onintr(int);
 101 void     printentry(struct utmp *, struct ttytab *);
 102 char    *ttyconv(char *);
 103 char    *ttyconv(char *);
 104 int      want(struct utmp *);
 105 void     usage(void);
 106 void     wtmp(void);
 107
 108 void
 109 usage(void)
 110 {
 111         (void)fprintf(stderr,
 112 "usage: last [-#] [-y] [-d [[CC]YY][MMDD]hhmm[.SS]] [-f file] [-h host]\n"
 113 "\t[-t tty] [-s|w] [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: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 's':
 156                         sflag++;        /* Show delta as seconds */
 157                         break;
 158                 case 't':
 159                         addarg(TTY_TYPE, ttyconv(optarg));
 160                         break;
 161                 case 'w':
 162                         width = 8;
 163                         break;
 164                 case 'y':
 165                         yflag++;
 166                         break;
 167                 case '?':
 168                 default:
 169                         usage();
 170                 }
 171
 172         if (sflag && width == 8) usage();
 173
 174         if (argc) {
 175                 setlinebuf(stdout);
 176                 for (argv += optind; *argv; ++argv) {
 177 #define COMPATIBILITY
 178 #ifdef  COMPATIBILITY
 179                         /* code to allow "last p5" to work */
 180                         addarg(TTY_TYPE, ttyconv(*argv));
 181 #endif
 182                         addarg(USER_TYPE, *argv);
 183                 }
 184         }
 185         wtmp();
 186         exit(0);
 187 }
 188
 189 /*
 190  * wtmp --
 191  *      read through the wtmp file
 192  */
 193 void
 194 wtmp(void)
 195 {
 196         struct utmp     *bp;                    /* current structure */
 197         struct stat     stb;                    /* stat of file for size */
 198         long    bl;
 199         int     bytes, wfd;
 200         char ct[80];
 201         struct tm *tm;
 202
 203         LIST_INIT(&ttylist);
 204
 205         if ((wfd = open(file, O_RDONLY, 0)) < 0 || fstat(wfd, &stb) == -1)
 206                 err(1, "%s", file);
 207         bl = (stb.st_size + sizeof(buf) - 1) / sizeof(buf);
 208
 209         (void)time(&buf[0].ut_time);
 210         (void)signal(SIGINT, onintr);
 211         (void)signal(SIGQUIT, onintr);
 212
 213         while (--bl >= 0) {
 214                 if (lseek(wfd, (off_t)(bl * sizeof(buf)), L_SET) == -1 ||
 215                     (bytes = read(wfd, buf, sizeof(buf))) == -1)
 216                         err(1, "%s", file);
 217                 for (bp = &buf[bytes / sizeof(buf[0]) - 1]; bp >= buf; --bp)
 218                         doentry(bp);
 219         }
 220         tm = localtime(&buf[0].ut_time);
 221         (void) strftime(ct, sizeof(ct), "\nwtmp begins %+\n", tm);
 222         printf("%s", ct);
 223 }
 224
 225 /*
 226  * doentry --
 227  *      process a single wtmp entry
 228  */
 229 void
 230 doentry(struct utmp *bp)
 231 {
 232         struct ttytab   *tt, *ttx;              /* ttylist entry */
 233
 234         /*
 235          * if the terminal line is '~', the machine stopped.
 236          * see utmp(5) for more info.
 237          */
 238         if (bp->ut_line[0] == '~' && !bp->ut_line[1]) {
 239                 /* everybody just logged out */
 240                 for (tt = LIST_FIRST(&ttylist); tt;) {
 241                         LIST_REMOVE(tt, list);
 242                         ttx = tt;
 243                         tt = LIST_NEXT(tt, list);
 244                         free(ttx);
 245                 }
 246                 currentout = -bp->ut_time;
 247                 crmsg = strncmp(bp->ut_name, "shutdown", UT_NAMESIZE) ?
 248                     "crash" : "shutdown";
 249                 /*
 250                  * if we're in snapshot mode, we want to exit if this
 251                  * shutdown/reboot appears while we we are tracking the
 252                  * active range
 253                  */
 254                 if (snaptime && snapfound)
 255                         exit(0);
 256                 /*
 257                  * don't print shutdown/reboot entries unless flagged for
 258                  */
 259                 if (!snaptime && want(bp))
 260                         printentry(bp, NULL);
 261                 return;
 262         }
 263         /*
 264          * if the line is '{' or '|', date got set; see
 265          * utmp(5) for more info.
 266          */
 267         if ((bp->ut_line[0] == '{' || bp->ut_line[0] == '|') &&
 268             !bp->ut_line[1]) {
 269                 if (want(bp) && !snaptime)
 270                         printentry(bp, NULL);
 271                 return;
 272         }
 273         /* find associated tty */
 274         LIST_FOREACH(tt, &ttylist, list)
 275             if (!strncmp(tt->tty, bp->ut_line, UT_LINESIZE))
 276                     break;
 277
 278         if (tt == NULL) {
 279                 /* add new one */
 280                 tt = malloc(sizeof(struct ttytab));
 281                 if (tt == NULL)
 282                         err(1, "malloc failure");
 283                 tt->logout = currentout;
 284                 strncpy(tt->tty, bp->ut_line, UT_LINESIZE);
 285                 LIST_INSERT_HEAD(&ttylist, tt, list);
 286         }
 287
 288         /*
 289          * print record if not in snapshot mode and wanted
 290          * or in snapshot mode and in snapshot range
 291          */
 292         if (bp->ut_name[0] && (want(bp) || (bp->ut_time < snaptime &&
 293             (tt->logout > snaptime || tt->logout < 1)))) {
 294                 snapfound = 1;
 295                 /*
 296                  * when uucp and ftp log in over a network, the entry in
 297                  * the utmp file is the name plus their process id.  See
 298                  * etc/ftpd.c and usr.bin/uucp/uucpd.c for more information.
 299                  */
 300                 if (!strncmp(bp->ut_line, "ftp", sizeof("ftp") - 1))
 301                         bp->ut_line[3] = '\0';
 302                 else if (!strncmp(bp->ut_line, "uucp", sizeof("uucp") - 1))
 303                         bp->ut_line[4] = '\0';
 304                 printentry(bp, tt);
 305         }
 306         tt->logout = bp->ut_time;
 307 }
 308
 309 /*
 310  * printentry --
 311  *      output an entry
 312  *
 313  * If `tt' is non-NULL, use it and `crmsg' to print the logout time or
 314  * logout type (crash/shutdown) as appropriate.
 315  */
 316 void
 317 printentry(struct utmp *bp, struct ttytab *tt)
 318 {
 319         char ct[80];
 320         struct tm *tm;
 321         time_t  delta;                          /* time difference */
 322
 323         if (maxrec != -1 && !maxrec--)
 324                 exit(0);
 325         tm = localtime(&bp->ut_time);
 326         (void) strftime(ct, sizeof(ct), d_first ?
 327             (yflag ? "%a %e %b %Y %R" : "%a %e %b %R") :
 328             (yflag ? "%a %b %e %Y %R" : "%a %b %e %R"), tm);
 329         printf("%-*.*s %-*.*s %-*.*s %s%c",
 330             UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
 331             UT_LINESIZE, UT_LINESIZE, bp->ut_line,
 332             UT_HOSTSIZE, UT_HOSTSIZE, bp->ut_host,
 333             ct, tt == NULL ? '\n' : ' ');
 334         if (tt == NULL)
 335                 return;
 336         if (!tt->logout) {
 337                 puts("  still logged in");
 338                 return;
 339         }
 340         if (tt->logout < 0) {
 341                 tt->logout = -tt->logout;
 342                 printf("- %s", crmsg);
 343         } else {
 344                 tm = localtime(&tt->logout);
 345                 (void) strftime(ct, sizeof(ct), "%R", tm);
 346                 printf("- %s", ct);
 347         }
 348         delta = tt->logout - bp->ut_time;
 349         if (sflag) {
 350                 printf("  (%8ld)\n", (long)delta);
 351         } else {
 352                 tm = gmtime(&delta);
 353                 (void) strftime(ct, sizeof(ct), width >= 8 ? "%T" : "%R", tm);
 354                 if (delta < 86400)
 355                         printf("  (%s)\n", ct);
 356                 else
 357                         printf(" (%ld+%s)\n", (long)delta / 86400, ct);
 358         }
 359 }
 360
 361 /*
 362  * want --
 363  *      see if want this entry
 364  */
 365 int
 366 want(struct utmp *bp)
 367 {
 368         ARG *step;
 369
 370         if (snaptime)
 371                 return (NO);
 372
 373         if (!arglist)
 374                 return (YES);
 375
 376         for (step = arglist; step; step = step->next)
 377                 switch(step->type) {
 378                 case HOST_TYPE:
 379                         if (!strncasecmp(step->name, bp->ut_host, UT_HOSTSIZE))
 380                                 return (YES);
 381                         break;
 382                 case TTY_TYPE:
 383                         if (!strncmp(step->name, bp->ut_line, UT_LINESIZE))
 384                                 return (YES);
 385                         break;
 386                 case USER_TYPE:
 387                         if (!strncmp(step->name, bp->ut_name, UT_NAMESIZE))
 388                                 return (YES);
 389                         break;
 390                 }
 391         return (NO);
 392 }
 393
 394 /*
 395  * addarg --
 396  *      add an entry to a linked list of arguments
 397  */
 398 void
 399 addarg(int type, char *arg)
 400 {
 401         ARG *cur;
 402
 403         if (!(cur = (ARG *)malloc((u_int)sizeof(ARG))))
 404                 err(1, "malloc failure");
 405         cur->next = arglist;
 406         cur->type = type;
 407         cur->name = arg;
 408         arglist = cur;
 409 }
 410
 411 /*
 412  * hostconv --
 413  *      convert the hostname to search pattern; if the supplied host name
 414  *      has a domain attached that is the same as the current domain, rip
 415  *      off the domain suffix since that's what login(1) does.
 416  */
 417 void
 418 hostconv(char *arg)
 419 {
 420         static int first = 1;
 421         static char *hostdot, name[MAXHOSTNAMELEN];
 422         char *argdot;
 423
 424         if (!(argdot = strchr(arg, '.')))
 425                 return;
 426         if (first) {
 427                 first = 0;
 428                 if (gethostname(name, sizeof(name)))
 429                         err(1, "gethostname");
 430                 hostdot = strchr(name, '.');
 431         }
 432         if (hostdot && !strcasecmp(hostdot, argdot))
 433                 *argdot = '\0';
 434 }
 435
 436 /*
 437  * ttyconv --
 438  *      convert tty to correct name.
 439  */
 440 char *
 441 ttyconv(char *arg)
 442 {
 443         char *mval;
 444
 445         /*
 446          * kludge -- we assume that all tty's end with
 447          * a two character suffix.
 448          */
 449         if (strlen(arg) == 2) {
 450                 /* either 6 for "ttyxx" or 8 for "console" */
 451                 if (!(mval = malloc((u_int)8)))
 452                         err(1, "malloc failure");
 453                 if (!strcmp(arg, "co"))
 454                         (void)strcpy(mval, "console");
 455                 else {
 456                         (void)strcpy(mval, "tty");
 457                         (void)strcpy(mval + 3, arg);
 458                 }
 459                 return (mval);
 460         }
 461         if (!strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1))
 462                 return (arg + 5);
 463         return (arg);
 464 }
 465
 466 /*
 467  * dateconv --
 468  *      Convert the snapshot time in command line given in the format
 469  *      [[CC]YY]MMDDhhmm[.SS]] to a time_t.
 470  *      Derived from atime_arg1() in usr.bin/touch/touch.c
 471  */
 472 time_t
 473 dateconv(char *arg)
 474 {
 475         time_t timet;
 476         struct tm *t;
 477         int yearset;
 478         char *p;
 479
 480         /* Start with the current time. */
 481         if (time(&timet) < 0)
 482                 err(1, "time");
 483         if ((t = localtime(&timet)) == NULL)
 484                 err(1, "localtime");
 485
 486         /* [[CC]YY]MMDDhhmm[.SS] */
 487         if ((p = strchr(arg, '.')) == NULL)
 488                 t->tm_sec = 0;          /* Seconds defaults to 0. */
 489         else {
 490                 if (strlen(p + 1) != 2)
 491                         goto terr;
 492                 *p++ = '\0';
 493                 t->tm_sec = ATOI2(p);
 494         }
 495
 496         yearset = 0;
 497         switch (strlen(arg)) {
 498         case 12:                        /* CCYYMMDDhhmm */
 499                 t->tm_year = ATOI2(arg);
 500                 t->tm_year *= 100;
 501                 yearset = 1;
 502                 /* FALLTHROUGH */
 503         case 10:                        /* YYMMDDhhmm */
 504                 if (yearset) {
 505                         yearset = ATOI2(arg);
 506                         t->tm_year += yearset;
 507                 } else {
 508                         yearset = ATOI2(arg);
 509                         if (yearset < 69)
 510                                 t->tm_year = yearset + 2000;
 511                         else
 512                                 t->tm_year = yearset + 1900;
 513                 }
 514                 t->tm_year -= 1900;     /* Convert to UNIX time. */
 515                 /* FALLTHROUGH */
 516         case 8:                         /* MMDDhhmm */
 517                 t->tm_mon = ATOI2(arg);
 518                 --t->tm_mon;            /* Convert from 01-12 to 00-11 */
 519                 t->tm_mday = ATOI2(arg);
 520                 t->tm_hour = ATOI2(arg);
 521                 t->tm_min = ATOI2(arg);
 522                 break;
 523         case 4:                         /* hhmm */
 524                 t->tm_hour = ATOI2(arg);
 525                 t->tm_min = ATOI2(arg);
 526                 break;
 527         default:
 528                 goto terr;
 529         }
 530         t->tm_isdst = -1;               /* Figure out DST. */
 531         timet = mktime(t);
 532         if (timet == -1)
 533 terr:           errx(1,
 534         "out of range or illegal time specification: [[CC]YY]MMDDhhmm[.SS]");
 535         return timet;
 536 }
 537
 538
 539 /*
 540  * onintr --
 541  *      on interrupt, we inform the user how far we've gotten
 542  */
 543 void
 544 onintr(int signo)
 545 {
 546         char ct[80];
 547         struct tm *tm;
 548
 549         tm = localtime(&buf[0].ut_time);
 550         (void) strftime(ct, sizeof(ct),
 551                         d_first ? "%a %e %b %R" : "%a %b %e %R",
 552                         tm);
 553         printf("\ninterrupted %s\n", ct);
 554         if (signo == SIGINT)
 555                 exit(1);
 556         (void)fflush(stdout);                   /* fix required for rsh */
 557 }