NetBSD/usr.sbin/lastlogin/lastlogin.c

539 lines
12 KiB
C

/* $NetBSD: lastlogin.c,v 1.20 2020/05/07 12:52:40 wiz Exp $ */
/*
* Copyright (c) 1996 John M. Vinopal
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project
* by John M. Vinopal.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: lastlogin.c,v 1.20 2020/05/07 12:52:40 wiz Exp $");
#endif
#include <sys/types.h>
#include <err.h>
#include <db.h>
#include <errno.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <time.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#ifdef SUPPORT_UTMP
#include <utmp.h>
#endif
#ifdef SUPPORT_UTMPX
#include <utmpx.h>
#endif
#include <unistd.h>
#include <util.h>
#ifndef UT_NAMESIZE
# define UT_NAMESIZE 8
#endif
#ifndef UT_LINESIZE
# define UT_LINESIZE 8
#endif
#ifndef UT_HOSTSIZE
# define UT_HOSTSIZE 16
#endif
#ifndef UTX_USERSIZE
# define UTX_USERSIZE 64
#endif
#ifndef UTX_LINESIZE
# define UTX_LINESIZE 64
#endif
#ifndef UTX_HOSTSIZE
# define UTX_HOSTSIZE 256
#endif
/*
* Fields in the structure below are 1 byte longer than the maximum possible
* for NUL-termination.
*/
struct output {
struct timeval o_tv;
char o_name[UTX_USERSIZE+1];
char o_line[UTX_LINESIZE+1];
char o_host[UTX_HOSTSIZE+1];
struct output *next;
};
#define SORT_NONE 0x0000
#define SORT_REVERSE 0x0001
#define SORT_TIME 0x0002
#define DOSORT(x) ((x) & (SORT_TIME))
static int sortlog = SORT_NONE;
static struct output *outstack = NULL;
static struct output *outstack_p = NULL;
static int fixed = 0;
#define FIXED_NAMELEN UT_NAMESIZE
#define FIXED_LINELEN UT_LINESIZE
/*
* This makes the "fixed" output fit in 79 columns.
* Using UT_HOSTSIZE (16) seems too conservative.
*/
#define FIXED_HOSTLEN 32
static int numeric = 0;
static size_t namelen = 0;
static size_t linelen = 0;
static size_t hostlen = 0;
#define SIZECOLUMNS (!(namelen && linelen && hostlen))
static int comparelog(const void *, const void *);
static void output_record(struct output *);
#ifdef SUPPORT_UTMP
static void process_entry(struct passwd *, struct lastlog *);
static void dolastlog(const char *, int, char *[]);
#endif
#ifdef SUPPORT_UTMPX
static void process_entryx(struct passwd *, struct lastlogx *);
static void dolastlogx(const char *, int, char *[]);
#endif
static void append_record(struct output *);
static void sizecolumns(struct output *);
static void output_stack(struct output *);
static void sort_and_output_stack(struct output *);
__dead static void usage(void);
int
main(int argc, char *argv[])
{
const char *logfile =
#if defined(SUPPORT_UTMPX)
_PATH_LASTLOGX;
#elif defined(SUPPORT_UTMP)
_PATH_LASTLOG;
#else
#error "either SUPPORT_UTMP or SUPPORT_UTMPX must be defined"
#endif
int ch;
size_t len;
while ((ch = getopt(argc, argv, "f:FH:L:nN:rt")) != -1) {
switch (ch) {
case 'H':
hostlen = atoi(optarg);
break;
case 'f':
logfile = optarg;
break;
case 'F':
fixed++;
break;
case 'L':
linelen = atoi(optarg);
break;
case 'n':
numeric++;
break;
case 'N':
namelen = atoi(optarg);
break;
case 'r':
sortlog |= SORT_REVERSE;
break;
case 't':
sortlog |= SORT_TIME;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (fixed) {
if (!namelen)
namelen = FIXED_NAMELEN;
if (!linelen)
linelen = FIXED_LINELEN;
if (!hostlen)
hostlen = FIXED_HOSTLEN;
}
len = strlen(logfile);
setpassent(1); /* Keep passwd file pointers open */
#if defined(SUPPORT_UTMPX)
if (len > 0 && logfile[len - 1] == 'x')
dolastlogx(logfile, argc, argv);
else
#endif
#if defined(SUPPORT_UTMP)
dolastlog(logfile, argc, argv);
#endif
setpassent(0); /* Close passwd file pointers */
if (outstack) {
if (SIZECOLUMNS)
sizecolumns(outstack);
if (DOSORT(sortlog))
sort_and_output_stack(outstack);
else
output_stack(outstack);
}
return 0;
}
#ifdef SUPPORT_UTMP
static void
dolastlog(const char *logfile, int argc, char **argv)
{
int i;
FILE *fp = fopen(logfile, "r");
struct passwd *passwd;
struct lastlog l;
if (fp == NULL)
err(1, "%s", logfile);
/* Process usernames given on the command line. */
if (argc > 0) {
off_t offset;
for (i = 0; i < argc; i++) {
if ((passwd = getpwnam(argv[i])) == NULL) {
warnx("user '%s' not found", argv[i]);
continue;
}
/* Calculate the offset into the lastlog file. */
offset = passwd->pw_uid * sizeof(l);
if (fseeko(fp, offset, SEEK_SET)) {
warn("fseek error");
continue;
}
if (fread(&l, sizeof(l), 1, fp) != 1) {
warnx("fread error on '%s'", passwd->pw_name);
clearerr(fp);
continue;
}
process_entry(passwd, &l);
}
}
/* Read all lastlog entries, looking for active ones */
else {
for (i = 0; fread(&l, sizeof(l), 1, fp) == 1; i++) {
if (l.ll_time == 0)
continue;
if ((passwd = getpwuid(i)) == NULL) {
static struct passwd p;
static char n[32];
snprintf(n, sizeof(n), "(%d)", i);
p.pw_uid = i;
p.pw_name = n;
passwd = &p;
}
process_entry(passwd, &l);
}
if (ferror(fp))
warnx("fread error");
}
(void)fclose(fp);
}
static void
process_entry(struct passwd *p, struct lastlog *l)
{
struct output o;
memset(&o, 0, sizeof(o));
if (numeric > 1)
(void)snprintf(o.o_name, sizeof(o.o_name), "%d", p->pw_uid);
else
(void)strlcpy(o.o_name, p->pw_name, sizeof(o.o_name));
(void)memcpy(o.o_line, l->ll_line, sizeof(l->ll_line));
(void)memcpy(o.o_host, l->ll_host, sizeof(l->ll_host));
o.o_tv.tv_sec = l->ll_time;
o.o_tv.tv_usec = 0;
o.next = NULL;
/*
* If we are dynamically sizing the columns or sorting the log,
* we need all the entries in memory so push the current entry
* onto a stack. Otherwise, we can just output it.
*/
if (SIZECOLUMNS || DOSORT(sortlog))
append_record(&o);
else
output_record(&o);
}
#endif
#ifdef SUPPORT_UTMPX
static void
dolastlogx(const char *logfile, int argc, char **argv)
{
int i = 0;
DB *db = dbopen(logfile, O_RDONLY|O_SHLOCK, 0, DB_HASH, NULL);
DBT key, data;
struct lastlogx l;
struct passwd *passwd;
if (db == NULL)
err(1, "%s", logfile);
if (argc > 0) {
for (i = 0; i < argc; i++) {
if ((passwd = getpwnam(argv[i])) == NULL) {
warnx("User `%s' not found", argv[i]);
continue;
}
key.data = &passwd->pw_uid;
key.size = sizeof(passwd->pw_uid);
switch ((*db->get)(db, &key, &data, 0)) {
case 0:
break;
case 1:
warnx("User `%s' not found", passwd->pw_name);
continue;
case -1:
warn("Error looking up `%s'", passwd->pw_name);
continue;
default:
abort();
}
if (data.size != sizeof(l)) {
errno = EFTYPE;
err(1, "%s", logfile);
}
(void)memcpy(&l, data.data, sizeof(l));
process_entryx(passwd, &l);
}
}
/* Read all lastlog entries, looking for active ones */
else {
switch ((*db->seq)(db, &key, &data, R_FIRST)) {
case 0:
break;
case 1:
warnx("No entries found");
(*db->close)(db);
return;
case -1:
warn("Error seeking to first entry");
(*db->close)(db);
return;
default:
abort();
}
do {
uid_t uid;
if (key.size != sizeof(uid) || data.size != sizeof(l)) {
errno = EFTYPE;
err(1, "%s", logfile);
}
(void)memcpy(&uid, key.data, sizeof(uid));
if ((passwd = getpwuid(uid)) == NULL) {
static struct passwd p;
static char n[32];
snprintf(n, sizeof(n), "(%d)", i);
p.pw_uid = i;
p.pw_name = n;
passwd = &p;
}
(void)memcpy(&l, data.data, sizeof(l));
process_entryx(passwd, &l);
} while ((i = (*db->seq)(db, &key, &data, R_NEXT)) == 0);
switch (i) {
case 1:
break;
case -1:
warn("Error seeking to last entry");
break;
case 0:
default:
abort();
}
}
(*db->close)(db);
}
static void
process_entryx(struct passwd *p, struct lastlogx *l)
{
struct output o;
memset(&o, 0, sizeof(o));
if (numeric > 1)
(void)snprintf(o.o_name, sizeof(o.o_name), "%d", p->pw_uid);
else
(void)strlcpy(o.o_name, p->pw_name, sizeof(o.o_name));
(void)memcpy(o.o_line, l->ll_line, sizeof(l->ll_line));
if (numeric)
(void)sockaddr_snprintf(o.o_host, sizeof(o.o_host), "%a",
(struct sockaddr *)&l->ll_ss);
else
(void)memcpy(o.o_host, l->ll_host, sizeof(l->ll_host));
o.o_tv = l->ll_tv;
o.next = NULL;
/*
* If we are dynamically sizing the columns or sorting the log,
* we need all the entries in memory so push the current entry
* onto a stack. Otherwise, we can just output it.
*/
if (SIZECOLUMNS || DOSORT(sortlog))
append_record(&o);
else
output_record(&o);
}
#endif
static void
append_record(struct output *o)
{
struct output *out;
out = malloc(sizeof(*out));
if (!out)
err(EXIT_FAILURE, "malloc failed");
(void)memcpy(out, o, sizeof(*out));
out->next = NULL;
if (outstack_p)
outstack_p = outstack_p->next = out;
else
outstack = outstack_p = out;
}
static void
sizecolumns(struct output *stack)
{
struct output *o;
size_t len;
if (!namelen)
for (o = stack; o; o = o->next) {
len = strlen(o->o_name);
if (namelen < len)
namelen = len;
}
if (!linelen)
for (o = stack; o; o = o->next) {
len = strlen(o->o_line);
if (linelen < len)
linelen = len;
}
if (!hostlen)
for (o = stack; o; o = o->next) {
len = strlen(o->o_host);
if (hostlen < len)
hostlen = len;
}
}
static void
output_stack(struct output *stack)
{
struct output *o;
for (o = stack; o; o = o->next)
output_record(o);
}
static void
sort_and_output_stack(struct output *o)
{
struct output **outs;
struct output *tmpo;
int num;
int i;
/* count the number of entries to display */
for (num=0, tmpo = o; tmpo; tmpo = tmpo->next, num++)
;
outs = malloc(sizeof(*outs) * num);
if (!outs)
err(EXIT_FAILURE, "malloc failed");
for (i=0, tmpo = o; i < num; tmpo=tmpo->next, i++)
outs[i] = tmpo;
mergesort(outs, num, sizeof(*outs), comparelog);
for (i=0; i < num; i++)
output_record(outs[i]);
}
static int
comparelog(const void *left, const void *right)
{
const struct output *l = *(const struct output * const *)left;
const struct output *r = *(const struct output * const *)right;
int order = (sortlog&SORT_REVERSE)?-1:1;
if (l->o_tv.tv_sec < r->o_tv.tv_sec)
return 1 * order;
if (l->o_tv.tv_sec == r->o_tv.tv_sec)
return 0;
return -1 * order;
}
/* Duplicate the output of last(1) */
static void
output_record(struct output *o)
{
time_t t = (time_t)o->o_tv.tv_sec;
printf("%-*.*s %-*.*s %-*.*s %s",
(int)namelen, (int)namelen, o->o_name,
(int)linelen, (int)linelen, o->o_line,
(int)hostlen, (int)hostlen, o->o_host,
t ? ctime(&t) : "Never logged in\n");
}
static void
usage(void)
{
(void)fprintf(stderr, "Usage: %s [-Fnrt] [-f filename] "
"[-H hostsize] [-L linesize] [-N namesize] [user ...]\n",
getprogname());
exit(1);
}