freebsd-dev/usr.bin/last/last.c
Pedro F. Giffuni 8a16b7a18f General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

574 lines
14 KiB
C

/*
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1987, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1987, 1993, 1994\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static const char sccsid[] = "@(#)last.c 8.2 (Berkeley) 4/2/94";
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/capsicum.h>
#include <sys/queue.h>
#include <sys/stat.h>
#include <capsicum_helpers.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <langinfo.h>
#include <locale.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <timeconv.h>
#include <unistd.h>
#include <utmpx.h>
#define NO 0 /* false/no */
#define YES 1 /* true/yes */
#define ATOI2(ar) ((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
typedef struct arg {
char *name; /* argument */
#define REBOOT_TYPE -1
#define HOST_TYPE -2
#define TTY_TYPE -3
#define USER_TYPE -4
int type; /* type of arg */
struct arg *next; /* linked list pointer */
} ARG;
static ARG *arglist; /* head of linked list */
static SLIST_HEAD(, idtab) idlist;
struct idtab {
time_t logout; /* log out time */
char id[sizeof ((struct utmpx *)0)->ut_id]; /* identifier */
SLIST_ENTRY(idtab) list;
};
static const char *crmsg; /* cause of last reboot */
static time_t currentout; /* current logout value */
static long maxrec; /* records to display */
static const char *file = NULL; /* utx.log file */
static int sflag = 0; /* show delta in seconds */
static int width = 5; /* show seconds in delta */
static int yflag; /* show year */
static int d_first;
static int snapfound = 0; /* found snapshot entry? */
static time_t snaptime; /* if != 0, we will only
* report users logged in
* at this snapshot time
*/
static void addarg(int, char *);
static time_t dateconv(char *);
static void doentry(struct utmpx *);
static void hostconv(char *);
static void printentry(struct utmpx *, struct idtab *);
static char *ttyconv(char *);
static int want(struct utmpx *);
static void usage(void);
static void wtmp(void);
static void
usage(void)
{
(void)fprintf(stderr,
"usage: last [-swy] [-d [[CC]YY][MMDD]hhmm[.SS]] [-f file] [-h host]\n"
" [-n maxrec] [-t tty] [user ...]\n");
exit(1);
}
int
main(int argc, char *argv[])
{
int ch;
char *p;
(void) setlocale(LC_TIME, "");
d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
maxrec = -1;
snaptime = 0;
while ((ch = getopt(argc, argv, "0123456789d:f:h:n:st:wy")) != -1)
switch (ch) {
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
/*
* kludge: last was originally designed to take
* a number after a dash.
*/
if (maxrec == -1) {
p = strchr(argv[optind - 1], ch);
if (p == NULL)
p = strchr(argv[optind], ch);
maxrec = atol(p);
if (!maxrec)
exit(0);
}
break;
case 'd':
snaptime = dateconv(optarg);
break;
case 'f':
file = optarg;
break;
case 'h':
hostconv(optarg);
addarg(HOST_TYPE, optarg);
break;
case 'n':
errno = 0;
maxrec = strtol(optarg, &p, 10);
if (p == optarg || *p != '\0' || errno != 0 ||
maxrec <= 0)
errx(1, "%s: bad line count", optarg);
break;
case 's':
sflag++; /* Show delta as seconds */
break;
case 't':
addarg(TTY_TYPE, ttyconv(optarg));
break;
case 'w':
width = 8;
break;
case 'y':
yflag++;
break;
case '?':
default:
usage();
}
if (caph_limit_stdio() < 0)
err(1, "can't limit stdio rights");
caph_cache_catpages();
caph_cache_tzdata();
/* Cache UTX database. */
if (setutxdb(UTXDB_LOG, file) != 0)
err(1, "%s", file != NULL ? file : "(default utx db)");
if (cap_enter() < 0 && errno != ENOSYS)
err(1, "cap_enter");
if (sflag && width == 8) usage();
if (argc) {
setlinebuf(stdout);
for (argv += optind; *argv; ++argv) {
if (strcmp(*argv, "reboot") == 0)
addarg(REBOOT_TYPE, *argv);
#define COMPATIBILITY
#ifdef COMPATIBILITY
/* code to allow "last p5" to work */
addarg(TTY_TYPE, ttyconv(*argv));
#endif
addarg(USER_TYPE, *argv);
}
}
wtmp();
exit(0);
}
/*
* wtmp --
* read through the utx.log file
*/
static void
wtmp(void)
{
struct utmpx *buf = NULL;
struct utmpx *ut;
static unsigned int amount = 0;
time_t t;
char ct[80];
struct tm *tm;
SLIST_INIT(&idlist);
(void)time(&t);
/* Load the last entries from the file. */
while ((ut = getutxent()) != NULL) {
if (amount % 128 == 0) {
buf = realloc(buf, (amount + 128) * sizeof *ut);
if (buf == NULL)
err(1, "realloc");
}
memcpy(&buf[amount++], ut, sizeof *ut);
if (t > ut->ut_tv.tv_sec)
t = ut->ut_tv.tv_sec;
}
endutxent();
/* Display them in reverse order. */
while (amount > 0)
doentry(&buf[--amount]);
free(buf);
tm = localtime(&t);
(void) strftime(ct, sizeof(ct), "%+", tm);
printf("\n%s begins %s\n", ((file == NULL) ? "utx.log" : file), ct);
}
/*
* doentry --
* process a single utx.log entry
*/
static void
doentry(struct utmpx *bp)
{
struct idtab *tt;
/* the machine stopped */
if (bp->ut_type == BOOT_TIME || bp->ut_type == SHUTDOWN_TIME) {
/* everybody just logged out */
while ((tt = SLIST_FIRST(&idlist)) != NULL) {
SLIST_REMOVE_HEAD(&idlist, list);
free(tt);
}
currentout = -bp->ut_tv.tv_sec;
crmsg = bp->ut_type != SHUTDOWN_TIME ?
"crash" : "shutdown";
/*
* if we're in snapshot mode, we want to exit if this
* shutdown/reboot appears while we we are tracking the
* active range
*/
if (snaptime && snapfound)
exit(0);
/*
* don't print shutdown/reboot entries unless flagged for
*/
if (!snaptime && want(bp))
printentry(bp, NULL);
return;
}
/* date got set */
if (bp->ut_type == OLD_TIME || bp->ut_type == NEW_TIME) {
if (want(bp) && !snaptime)
printentry(bp, NULL);
return;
}
if (bp->ut_type != USER_PROCESS && bp->ut_type != DEAD_PROCESS)
return;
/* find associated identifier */
SLIST_FOREACH(tt, &idlist, list)
if (!memcmp(tt->id, bp->ut_id, sizeof bp->ut_id))
break;
if (tt == NULL) {
/* add new one */
tt = malloc(sizeof(struct idtab));
if (tt == NULL)
errx(1, "malloc failure");
tt->logout = currentout;
memcpy(tt->id, bp->ut_id, sizeof bp->ut_id);
SLIST_INSERT_HEAD(&idlist, tt, list);
}
/*
* print record if not in snapshot mode and wanted
* or in snapshot mode and in snapshot range
*/
if (bp->ut_type == USER_PROCESS && (want(bp) ||
(bp->ut_tv.tv_sec < snaptime &&
(tt->logout > snaptime || tt->logout < 1)))) {
snapfound = 1;
printentry(bp, tt);
}
tt->logout = bp->ut_tv.tv_sec;
}
/*
* printentry --
* output an entry
*
* If `tt' is non-NULL, use it and `crmsg' to print the logout time or
* logout type (crash/shutdown) as appropriate.
*/
static void
printentry(struct utmpx *bp, struct idtab *tt)
{
char ct[80];
struct tm *tm;
time_t delta; /* time difference */
time_t t;
if (maxrec != -1 && !maxrec--)
exit(0);
t = bp->ut_tv.tv_sec;
tm = localtime(&t);
(void) strftime(ct, sizeof(ct), d_first ?
(yflag ? "%a %e %b %Y %R" : "%a %e %b %R") :
(yflag ? "%a %b %e %Y %R" : "%a %b %e %R"), tm);
switch (bp->ut_type) {
case BOOT_TIME:
printf("%-42s", "boot time");
break;
case SHUTDOWN_TIME:
printf("%-42s", "shutdown time");
break;
case OLD_TIME:
printf("%-42s", "old time");
break;
case NEW_TIME:
printf("%-42s", "new time");
break;
case USER_PROCESS:
printf("%-10s %-8s %-22.22s",
bp->ut_user, bp->ut_line, bp->ut_host);
break;
}
printf(" %s%c", ct, tt == NULL ? '\n' : ' ');
if (tt == NULL)
return;
if (!tt->logout) {
puts(" still logged in");
return;
}
if (tt->logout < 0) {
tt->logout = -tt->logout;
printf("- %s", crmsg);
} else {
tm = localtime(&tt->logout);
(void) strftime(ct, sizeof(ct), "%R", tm);
printf("- %s", ct);
}
delta = tt->logout - bp->ut_tv.tv_sec;
if (sflag) {
printf(" (%8ld)\n", (long)delta);
} else {
tm = gmtime(&delta);
(void) strftime(ct, sizeof(ct), width >= 8 ? "%T" : "%R", tm);
if (delta < 86400)
printf(" (%s)\n", ct);
else
printf(" (%ld+%s)\n", (long)delta / 86400, ct);
}
}
/*
* want --
* see if want this entry
*/
static int
want(struct utmpx *bp)
{
ARG *step;
if (snaptime)
return (NO);
if (!arglist)
return (YES);
for (step = arglist; step; step = step->next)
switch(step->type) {
case REBOOT_TYPE:
if (bp->ut_type == BOOT_TIME ||
bp->ut_type == SHUTDOWN_TIME)
return (YES);
break;
case HOST_TYPE:
if (!strcasecmp(step->name, bp->ut_host))
return (YES);
break;
case TTY_TYPE:
if (!strcmp(step->name, bp->ut_line))
return (YES);
break;
case USER_TYPE:
if (!strcmp(step->name, bp->ut_user))
return (YES);
break;
}
return (NO);
}
/*
* addarg --
* add an entry to a linked list of arguments
*/
static void
addarg(int type, char *arg)
{
ARG *cur;
if ((cur = malloc(sizeof(ARG))) == NULL)
errx(1, "malloc failure");
cur->next = arglist;
cur->type = type;
cur->name = arg;
arglist = cur;
}
/*
* hostconv --
* convert the hostname to search pattern; if the supplied host name
* has a domain attached that is the same as the current domain, rip
* off the domain suffix since that's what login(1) does.
*/
static void
hostconv(char *arg)
{
static int first = 1;
static char *hostdot, name[MAXHOSTNAMELEN];
char *argdot;
if (!(argdot = strchr(arg, '.')))
return;
if (first) {
first = 0;
if (gethostname(name, sizeof(name)))
err(1, "gethostname");
hostdot = strchr(name, '.');
}
if (hostdot && !strcasecmp(hostdot, argdot))
*argdot = '\0';
}
/*
* ttyconv --
* convert tty to correct name.
*/
static char *
ttyconv(char *arg)
{
char *mval;
/*
* kludge -- we assume that all tty's end with
* a two character suffix.
*/
if (strlen(arg) == 2) {
/* either 6 for "ttyxx" or 8 for "console" */
if ((mval = malloc(8)) == NULL)
errx(1, "malloc failure");
if (!strcmp(arg, "co"))
(void)strcpy(mval, "console");
else {
(void)strcpy(mval, "tty");
(void)strcpy(mval + 3, arg);
}
return (mval);
}
if (!strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1))
return (arg + 5);
return (arg);
}
/*
* dateconv --
* Convert the snapshot time in command line given in the format
* [[CC]YY]MMDDhhmm[.SS]] to a time_t.
* Derived from atime_arg1() in usr.bin/touch/touch.c
*/
static time_t
dateconv(char *arg)
{
time_t timet;
struct tm *t;
int yearset;
char *p;
/* Start with the current time. */
if (time(&timet) < 0)
err(1, "time");
if ((t = localtime(&timet)) == NULL)
err(1, "localtime");
/* [[CC]YY]MMDDhhmm[.SS] */
if ((p = strchr(arg, '.')) == NULL)
t->tm_sec = 0; /* Seconds defaults to 0. */
else {
if (strlen(p + 1) != 2)
goto terr;
*p++ = '\0';
t->tm_sec = ATOI2(p);
}
yearset = 0;
switch (strlen(arg)) {
case 12: /* CCYYMMDDhhmm */
t->tm_year = ATOI2(arg);
t->tm_year *= 100;
yearset = 1;
/* FALLTHROUGH */
case 10: /* YYMMDDhhmm */
if (yearset) {
yearset = ATOI2(arg);
t->tm_year += yearset;
} else {
yearset = ATOI2(arg);
if (yearset < 69)
t->tm_year = yearset + 2000;
else
t->tm_year = yearset + 1900;
}
t->tm_year -= 1900; /* Convert to UNIX time. */
/* FALLTHROUGH */
case 8: /* MMDDhhmm */
t->tm_mon = ATOI2(arg);
--t->tm_mon; /* Convert from 01-12 to 00-11 */
t->tm_mday = ATOI2(arg);
t->tm_hour = ATOI2(arg);
t->tm_min = ATOI2(arg);
break;
case 4: /* hhmm */
t->tm_hour = ATOI2(arg);
t->tm_min = ATOI2(arg);
break;
default:
goto terr;
}
t->tm_isdst = -1; /* Figure out DST. */
timet = mktime(t);
if (timet == -1)
terr: errx(1,
"out of range or illegal time specification: [[CC]YY]MMDDhhmm[.SS]");
return timet;
}