usr.bin/last/want.c

   1 /*      $NetBSD: want.c,v 1.17 2012/03/15 03:04:05 dholland Exp $       */
   2
   3 /*
   4  * Copyright (c) 1987, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31 static struct utmp *buf;
  32 static time_t seentime;
  33
  34 static void onintr(int);
  35 static int want(struct utmp *, int);
  36 static const char *gethost(struct utmp *, const char *, int);
  37
  38 static const char *
  39 /*ARGSUSED*/
  40 gethost(struct utmp *ut, const char *host, int numeric)
  41 {
  42 #if HAS_UT_SS == 0
  43         return numeric ? "" : host;
  44 #else
  45         if (numeric) {
  46                 static char hbuf[512];
  47                 hbuf[0] = '\0';
  48                 (void)sockaddr_snprintf(hbuf, sizeof(hbuf), "%a",
  49                     (struct sockaddr *)&ut->ut_ss);
  50                 return hbuf;
  51         } else
  52                 return host;
  53 #endif
  54 }
  55
  56 #define NULTERM(what) \
  57         if (check ## what) \
  58                 (void)strlcpy(what ## p = what ## buf, bp->ut_ ## what, \
  59                     sizeof(what ## buf)); \
  60         else \
  61                 what ## p = bp->ut_ ## what
  62
  63 /*
  64  * wtmp --
  65  *      read through the wtmp file
  66  */
  67 static void
  68 wtmp(const char *file, int namesz, int linesz, int hostsz, int numeric)
  69 {
  70         struct utmp     *bp;            /* current structure */
  71         TTY     *T;                     /* tty list entry */
  72         struct stat     stb;            /* stat of file for sz */
  73         off_t   offset;
  74         int     wfd;
  75         char    *ct;
  76         const char *crmsg;
  77         size_t  len = sizeof(*buf) * MAXUTMP;
  78         char namebuf[sizeof(bp->ut_name) + 1], *namep;
  79         char linebuf[sizeof(bp->ut_line) + 1], *linep;
  80         char hostbuf[sizeof(bp->ut_host) + 1], *hostp;
  81         int checkname = namesz > (int)sizeof(bp->ut_name);
  82         int checkline = linesz > (int)sizeof(bp->ut_line);
  83         int checkhost = hostsz > (int)sizeof(bp->ut_host);
  84
  85         if ((buf = malloc(len)) == NULL)
  86                 err(EXIT_FAILURE, "Cannot allocate utmp buffer");
  87
  88         crmsg = NULL;
  89
  90         if (!strcmp(file, "-")) {
  91                 wfd = STDIN_FILENO;
  92                 file = "<stdin>";
  93         } else if ((wfd = open(file, O_RDONLY, 0)) < 0) {
  94                 err(EXIT_FAILURE, "%s", file);
  95         }
  96
  97         if (lseek(wfd, 0, SEEK_CUR) < 0) {
  98                 const char *dir;
  99                 char *tfile;
 100                 int tempfd;
 101                 ssize_t tlen;
 102
 103                 if (ESPIPE != errno) {
 104                         err(EXIT_FAILURE, "lseek");
 105                 }
 106                 dir = getenv("TMPDIR");
 107                 if (asprintf(&tfile, "%s/last.XXXXXX", dir ? dir : _PATH_TMP) == -1)
 108                         err(EXIT_FAILURE, "asprintf");
 109                 tempfd = mkstemp(tfile);
 110                 if (tempfd < 0) {
 111                         err(EXIT_FAILURE, "mkstemp");
 112                 }
 113                 unlink(tfile);
 114                 for (;;) {
 115                         tlen = read(wfd, buf, len);
 116                         if (tlen < 0) {
 117                                 err(1, "%s: read", file);
 118                         }
 119                         if (tlen == 0) {
 120                                 break;
 121                         }
 122                         if (write(tempfd, buf, tlen) != tlen) {
 123                                 err(1, "%s: write", tfile);
 124                         }
 125                 }
 126                 wfd = tempfd;
 127         }
 128
 129         if (fstat(wfd, &stb) == -1)
 130                 err(EXIT_FAILURE, "%s: fstat", file);
 131         if (!S_ISREG(stb.st_mode))
 132                 errx(EXIT_FAILURE, "%s: Not a regular file", file);
 133
 134         seentime = stb.st_mtime;
 135         (void)signal(SIGINT, onintr);
 136         (void)signal(SIGQUIT, onintr);
 137
 138         offset = stb.st_size;
 139         /* Ignore trailing garbage or partial record */
 140         offset -= offset % (off_t) sizeof(*buf);
 141
 142         while (offset >= (off_t) sizeof(*buf)) {
 143                 ssize_t ret, i;
 144                 size_t size;
 145
 146                 size = MIN((off_t)len, offset);
 147                 offset -= size; /* Always a multiple of sizeof(*buf) */
 148                 ret = pread(wfd, buf, size, offset);
 149                 if (ret < 0) {
 150                         err(EXIT_FAILURE, "%s: pread", file);
 151                 } else if ((size_t) ret < size) {
 152                         err(EXIT_FAILURE, "%s: Unexpected end of file", file);
 153                 }
 154
 155                 for (i = ret / sizeof(*buf) - 1; i >= 0; i--) {
 156                         bp = &buf[i];
 157
 158                         NULTERM(name);
 159                         NULTERM(line);
 160                         NULTERM(host);
 161
 162                         seentime = bp->ut_timefld;
 163
 164                         /*
 165                          * if the terminal line is '~', the machine stopped.
 166                          * see utmp(5) for more info.
 167                          */
 168                         if (linep[0] == '~' && !linep[1]) {
 169                                 /* everybody just logged out */
 170                                 for (T = ttylist; T; T = T->next)
 171                                         T->logout = -bp->ut_timefld;
 172                                 currentout = -bp->ut_timefld;
 173                                 crmsg = strncmp(namep, "shutdown",
 174                                     namesz) ? "crash" : "shutdown";
 175                                 if (want(bp, NO)) {
 176                                         ct = fmttime(bp->ut_timefld, fulltime);
 177                                         printf("%-*.*s  %-*.*s %-*.*s %s\n",
 178                                             namesz, namesz, namep,
 179                                             linesz, linesz, linep,
 180                                             hostsz, hostsz,
 181                                             gethost(bp, hostp, numeric), ct);
 182                                         if (maxrec != -1 && !--maxrec)
 183                                                 return;
 184                                 }
 185                                 continue;
 186                         }
 187                         /*
 188                          * if the line is '{' or '|', date got set; see
 189                          * utmp(5) for more info.
 190                          */
 191                         if ((linep[0] == '{' || linep[0] == '|') && !linep[1]) {
 192                                 if (want(bp, NO)) {
 193                                         ct = fmttime(bp->ut_timefld, fulltime);
 194                                         printf("%-*.*s  %-*.*s %-*.*s %s\n",
 195                                             namesz, namesz, namep,
 196                                             linesz, linesz, linep,
 197                                             hostsz, hostsz,
 198                                             gethost(bp, hostp, numeric),
 199                                             ct);
 200                                         if (maxrec && !--maxrec)
 201                                                 return;
 202                                 }
 203                                 continue;
 204                         }
 205                         /* find associated tty */
 206                         for (T = ttylist;; T = T->next) {
 207                                 if (!T) {
 208                                         /* add new one */
 209                                         T = addtty(linep);
 210                                         break;
 211                                 }
 212                                 if (!strncmp(T->tty, linep, LINESIZE))
 213                                         break;
 214                         }
 215                         if (TYPE(bp) == SIGNATURE)
 216                                 continue;
 217                         if (namep[0] && want(bp, YES)) {
 218                                 ct = fmttime(bp->ut_timefld, fulltime);
 219                                 printf("%-*.*s  %-*.*s %-*.*s %s ",
 220                                     namesz, namesz, namep,
 221                                     linesz, linesz, linep,
 222                                     hostsz, hostsz,
 223                                     gethost(bp, hostp, numeric),
 224                                     ct);
 225                                 if (!T->logout)
 226                                         puts("  still logged in");
 227                                 else {
 228                                         time_t  delta;                  /* time difference */
 229
 230                                         if (T->logout < 0) {
 231                                                 T->logout = -T->logout;
 232                                                 printf("- %s", crmsg);
 233                                         }
 234                                         else
 235                                                 printf("- %s",
 236                                                     fmttime(T->logout,
 237                                                     fulltime | TIMEONLY));
 238                                         delta = T->logout - bp->ut_timefld;
 239                                         if (delta < SECSPERDAY)
 240                                                 printf("  (%s)\n",
 241                                                     fmttime(delta,
 242                                                     fulltime | TIMEONLY | GMT));
 243                                         else
 244                                                 printf(" (%lld+%s)\n",
 245                                                     (long long)
 246                                                     delta / SECSPERDAY,
 247                                                     fmttime(delta,
 248                                                     fulltime | TIMEONLY | GMT));
 249                                 }
 250                                 if (maxrec != -1 && !--maxrec)
 251                                         return;
 252                         }
 253                         T->logout = bp->ut_timefld;
 254                 }
 255         }
 256         fulltime = 1;   /* show full time */
 257         crmsg = fmttime(seentime, FULLTIME);
 258         if ((ct = strrchr(file, '/')) != NULL)
 259                 ct++;
 260         printf("\n%s begins %s\n", ct ? ct : file, crmsg);
 261 }
 262
 263 /*
 264  * want --
 265  *      see if want this entry
 266  */
 267 static int
 268 want(struct utmp *bp, int check)
 269 {
 270         ARG *step;
 271
 272         if (check) {
 273                 /*
 274                  * when uucp and ftp log in over a network, the entry in
 275                  * the utmp file is the name plus their process id.  See
 276                  * etc/ftpd.c and usr.bin/uucp/uucpd.c for more information.
 277                  */
 278                 if (!strncmp(bp->ut_line, "ftp", sizeof("ftp") - 1))
 279                         bp->ut_line[3] = '\0';
 280                 else if (!strncmp(bp->ut_line, "uucp", sizeof("uucp") - 1))
 281                         bp->ut_line[4] = '\0';
 282         }
 283         if (!arglist)
 284                 return (YES);
 285
 286         for (step = arglist; step; step = step->next)
 287                 switch(step->type) {
 288                 case HOST_TYPE:
 289                         if (!strncasecmp(step->name, bp->ut_host, HOSTSIZE))
 290                                 return (YES);
 291                         break;
 292                 case TTY_TYPE:
 293                         if (!strncmp(step->name, bp->ut_line, LINESIZE))
 294                                 return (YES);
 295                         break;
 296                 case USER_TYPE:
 297                         if (!strncmp(step->name, bp->ut_name, NAMESIZE))
 298                                 return (YES);
 299                         break;
 300         }
 301         return (NO);
 302 }
 303
 304 /*
 305  * onintr --
 306  *      on interrupt, we inform the user how far we've gotten
 307  */
 308 static void
 309 onintr(int signo)
 310 {
 311         /* FIXME: None of this is allowed in a signal handler */
 312         printf("\ninterrupted %s\n", fmttime(seentime, FULLTIME));
 313         if (signo == SIGINT) {
 314                 (void)raise_default_signal(signo);
 315                 exit(EXIT_FAILURE);
 316         }
 317         (void)fflush(stdout);           /* fix required for rsh */
 318 }