1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-20 11:11:24 +00:00
freebsd/usr.sbin/ac/ac.c
Garance A Drosehn e3b218cd7b Add a check for wtmp records which have invalid values for ut_time. Wtmp
records with time==0 get "the time of the last valid record", while records
where time goes backwards (compared to the previous record) are skipped.
Also prints a message saying how many records were changed or skipped due
to these checks. Check was inspired by a simpler check in OpenBSD's version.

This is all meant to sidestep problems that Tillman Hodgson noticed with 'ac'
when running sparc64 with 64-bit time_t's.  The real problem is whatever is
creating wtmp records with ut_time==0, of course, but I have not yet figured
out what is doing that.

Reviewed by:	no screams from freebsd-sparc64 or bde
MFC after:	2 weeks
2004-03-08 20:02:23 +00:00

669 lines
15 KiB
C

/*
* Copyright (c) 1994 Christopher G. Demetriou.
* @(#)Copyright (c) 1994, Simon J. Gerraty.
*
* This is free software. It comes with NO WARRANTY.
* Permission to use, modify and distribute this source code
* is granted subject to the following conditions.
* 1/ that the above copyright notice and this notice
* are preserved in all copies and that due credit be given
* to the author.
* 2/ that any changes to this code are clearly commented
* as such so that the author does not get blamed for bugs
* other than his own.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/time.h>
#include <err.h>
#include <errno.h>
#include <langinfo.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <timeconv.h>
#include <unistd.h>
#include <utmp.h>
/*
* this is for our list of currently logged in sessions
*/
struct utmp_list {
struct utmp_list *next;
struct utmp usr;
};
/*
* this is for our list of users that are accumulating time.
*/
struct user_list {
struct user_list *next;
char name[UT_NAMESIZE+1];
time_t secs;
};
/*
* this is for chosing whether to ignore a login
*/
struct tty_list {
struct tty_list *next;
char name[UT_LINESIZE+3];
size_t len;
int ret;
};
/*
* globals - yes yuk
*/
#ifdef CONSOLE_TTY
static char *Console = CONSOLE_TTY;
#endif
static time_t Total = 0;
static time_t FirstTime = 0;
static int Flags = 0;
static struct user_list *Users = NULL;
static struct tty_list *Ttys = NULL;
#define NEW(type) (type *)malloc(sizeof (type))
#define AC_W 1 /* not _PATH_WTMP */
#define AC_D 2 /* daily totals (ignore -p) */
#define AC_P 4 /* per-user totals */
#define AC_U 8 /* specified users only */
#define AC_T 16 /* specified ttys only */
#ifdef DEBUG
static int Debug = 0;
#endif
int main(int, char **);
int ac(FILE *);
struct tty_list *add_tty(char *);
#ifdef DEBUG
const char *debug_pfx(const struct utmp *, const struct utmp *);
#endif
int do_tty(char *);
FILE *file(const char *);
struct utmp_list *log_in(struct utmp_list *, struct utmp *);
struct utmp_list *log_out(struct utmp_list *, struct utmp *);
int on_console(struct utmp_list *);
void show(const char *, time_t);
void show_today(struct user_list *, struct utmp_list *,
time_t);
void show_users(struct user_list *);
struct user_list *update_user(struct user_list *, char *, time_t);
void usage(void);
/*
* open wtmp or die
*/
FILE *
file(const char *name)
{
FILE *fp;
if ((fp = fopen(name, "r")) == NULL)
err(1, "%s", name);
/* in case we want to discriminate */
if (strcmp(_PATH_WTMP, name))
Flags |= AC_W;
return fp;
}
struct tty_list *
add_tty(char *name)
{
struct tty_list *tp;
char *rcp;
Flags |= AC_T;
if ((tp = NEW(struct tty_list)) == NULL)
errx(1, "malloc failed");
tp->len = 0; /* full match */
tp->ret = 1; /* do if match */
if (*name == '!') { /* don't do if match */
tp->ret = 0;
name++;
}
strlcpy(tp->name, name, sizeof (tp->name));
if ((rcp = strchr(tp->name, '*')) != NULL) { /* wild card */
*rcp = '\0';
tp->len = strlen(tp->name); /* match len bytes only */
}
tp->next = Ttys;
Ttys = tp;
return Ttys;
}
/*
* should we process the named tty?
*/
int
do_tty(char *name)
{
struct tty_list *tp;
int def_ret = 0;
for (tp = Ttys; tp != NULL; tp = tp->next) {
if (tp->ret == 0) /* specific don't */
def_ret = 1; /* default do */
if (tp->len != 0) {
if (strncmp(name, tp->name, tp->len) == 0)
return tp->ret;
} else {
if (strncmp(name, tp->name, sizeof (tp->name)) == 0)
return tp->ret;
}
}
return def_ret;
}
#ifdef CONSOLE_TTY
/*
* is someone logged in on Console?
*/
int
on_console(struct utmp_list *head)
{
struct utmp_list *up;
for (up = head; up; up = up->next) {
if (strncmp(up->usr.ut_line, Console,
sizeof (up->usr.ut_line)) == 0)
return 1;
}
return 0;
}
#endif
/*
* update user's login time
*/
struct user_list *
update_user(struct user_list *head, char *name, time_t secs)
{
struct user_list *up;
for (up = head; up != NULL; up = up->next) {
if (strncmp(up->name, name, UT_NAMESIZE) == 0) {
up->secs += secs;
Total += secs;
return head;
}
}
/*
* not found so add new user unless specified users only
*/
if (Flags & AC_U)
return head;
if ((up = NEW(struct user_list)) == NULL)
errx(1, "malloc failed");
up->next = head;
strlcpy(up->name, name, sizeof (up->name));
up->secs = secs;
Total += secs;
return up;
}
#ifdef DEBUG
/*
* Create a string which is the standard prefix for a debug line. It
* includes a timestamp (perhaps with year), device-name, and user-name.
*/
const char *
debug_pfx(const struct utmp *event_up, const struct utmp *userinf_up)
{
static char str_result[40+UT_LINESIZE+UT_NAMESIZE];
static char thisyear[5];
size_t maxcopy;
time_t ut_timecopy;
if (thisyear[0] == '\0') {
/* Figure out what "this year" is. */
time(&ut_timecopy);
strlcpy(str_result, ctime(&ut_timecopy), sizeof(str_result));
strlcpy(thisyear, &str_result[20], sizeof(thisyear));
}
if (event_up->ut_time == 0)
strlcpy(str_result, "*ZeroTime* --:--:-- ", sizeof(str_result));
else {
/*
* The type of utmp.ut_time is not necessary type time_t, as
* it is explicitly defined as type int32_t. Copy the value
* for platforms where sizeof(time_t) != sizeof(int32_t).
*/
ut_timecopy = _time32_to_time(event_up->ut_time);
strlcpy(str_result, ctime(&ut_timecopy), sizeof(str_result));
/*
* Include the year, if it is not the same year as "now".
*/
if (strncmp(&str_result[20], thisyear, 4) == 0)
str_result[20] = '\0';
else {
str_result[24] = ' '; /* Replace a '\n' */
str_result[25] = '\0';
}
}
if (userinf_up->ut_line[0] == '\0')
strlcat(str_result, "NoDev", sizeof(str_result));
else {
/* ut_line is not necessarily null-terminated. */
maxcopy = strlen(str_result) + UT_LINESIZE + 1;
if (maxcopy > sizeof(str_result))
maxcopy = sizeof(str_result);
strlcat(str_result, userinf_up->ut_line, maxcopy);
}
strlcat(str_result, ": ", sizeof(str_result));
if (userinf_up->ut_name[0] == '\0')
strlcat(str_result, "LogOff", sizeof(str_result));
else {
/* ut_name is not necessarily null-terminated. */
maxcopy = strlen(str_result) + UT_NAMESIZE + 1;
if (maxcopy > sizeof(str_result))
maxcopy = sizeof(str_result);
strlcat(str_result, userinf_up->ut_name, maxcopy);
}
return (str_result);
}
#endif
int
main(int argc, char *argv[])
{
FILE *fp;
int c;
(void) setlocale(LC_TIME, "");
fp = NULL;
while ((c = getopt(argc, argv, "Dc:dpt:w:")) != -1) {
switch (c) {
#ifdef DEBUG
case 'D':
Debug++;
break;
#endif
case 'c':
#ifdef CONSOLE_TTY
Console = optarg;
#else
usage(); /* XXX */
#endif
break;
case 'd':
Flags |= AC_D;
break;
case 'p':
Flags |= AC_P;
break;
case 't': /* only do specified ttys */
add_tty(optarg);
break;
case 'w':
fp = file(optarg);
break;
case '?':
default:
usage();
break;
}
}
if (optind < argc) {
/*
* initialize user list
*/
for (; optind < argc; optind++) {
Users = update_user(Users, argv[optind], (time_t)0);
}
Flags |= AC_U; /* freeze user list */
}
if (Flags & AC_D)
Flags &= ~AC_P;
if (fp == NULL) {
/*
* if _PATH_WTMP does not exist, exit quietly
*/
if (access(_PATH_WTMP, 0) != 0 && errno == ENOENT)
return 0;
fp = file(_PATH_WTMP);
}
ac(fp);
return 0;
}
/*
* print login time in decimal hours
*/
void
show(const char *name, time_t secs)
{
(void)printf("\t%-*s %8.2f\n", UT_NAMESIZE, name,
((double)secs / 3600));
}
void
show_users(struct user_list *list)
{
struct user_list *lp;
for (lp = list; lp; lp = lp->next)
show(lp->name, lp->secs);
}
/*
* print total login time for 24hr period in decimal hours
*/
void
show_today(struct user_list *users, struct utmp_list *logins, time_t secs)
{
struct user_list *up;
struct utmp_list *lp;
char date[64];
time_t yesterday = secs - 1;
static int d_first = -1;
if (d_first < 0)
d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
(void)strftime(date, sizeof (date),
d_first ? "%e %b total" : "%b %e total",
localtime(&yesterday));
/* restore the missing second */
yesterday++;
for (lp = logins; lp != NULL; lp = lp->next) {
secs = yesterday - lp->usr.ut_time;
Users = update_user(Users, lp->usr.ut_name, secs);
lp->usr.ut_time = yesterday; /* as if they just logged in */
}
secs = 0;
for (up = users; up != NULL; up = up->next) {
secs += up->secs;
up->secs = 0; /* for next day */
}
if (secs)
(void)printf("%s %11.2f\n", date, ((double)secs / 3600));
}
/*
* log a user out and update their times.
* if ut_line is "~", we log all users out as the system has
* been shut down.
*/
struct utmp_list *
log_out(struct utmp_list *head, struct utmp *up)
{
struct utmp_list *lp, *lp2, *tlp;
time_t secs;
for (lp = head, lp2 = NULL; lp != NULL; )
if (*up->ut_line == '~' || strncmp(lp->usr.ut_line, up->ut_line,
sizeof (up->ut_line)) == 0) {
secs = up->ut_time - lp->usr.ut_time;
Users = update_user(Users, lp->usr.ut_name, secs);
#ifdef DEBUG
if (Debug)
printf("%s logged out (%2d:%02d:%02d)\n",
debug_pfx(up, &lp->usr), (int)(secs / 3600),
(int)((secs % 3600) / 60),
(int)(secs % 60));
#endif
/*
* now lose it
*/
tlp = lp;
lp = lp->next;
if (tlp == head)
head = lp;
else if (lp2 != NULL)
lp2->next = lp;
free(tlp);
} else {
lp2 = lp;
lp = lp->next;
}
return head;
}
/*
* if do_tty says ok, login a user
*/
struct utmp_list *
log_in(struct utmp_list *head, struct utmp *up)
{
struct utmp_list *lp;
/*
* this could be a login. if we're not dealing with
* the console name, say it is.
*
* If we are, and if ut_host==":0.0" we know that it
* isn't a real login. _But_ if we have not yet recorded
* someone being logged in on Console - due to the wtmp
* file starting after they logged in, we'll pretend they
* logged in, at the start of the wtmp file.
*/
#ifdef CONSOLE_TTY
if (up->ut_host[0] == ':') {
/*
* SunOS 4.0.2 does not treat ":0.0" as special but we
* do.
*/
if (on_console(head))
return head;
/*
* ok, no recorded login, so they were here when wtmp
* started! Adjust ut_time!
*/
up->ut_time = FirstTime;
/*
* this allows us to pick the right logout
*/
strlcpy(up->ut_line, Console, sizeof (up->ut_line));
}
#endif
/*
* If we are doing specified ttys only, we ignore
* anything else.
*/
if (Flags & AC_T)
if (!do_tty(up->ut_line))
return head;
/*
* go ahead and log them in
*/
if ((lp = NEW(struct utmp_list)) == NULL)
errx(1, "malloc failed");
lp->next = head;
head = lp;
memmove((char *)&lp->usr, (char *)up, sizeof (struct utmp));
#ifdef DEBUG
if (Debug) {
printf("%s logged in", debug_pfx(&lp->usr, up));
if (*up->ut_host)
printf(" (%-.*s)", (int)sizeof(up->ut_host),
up->ut_host);
putchar('\n');
}
#endif
return head;
}
int
ac(FILE *fp)
{
struct utmp_list *lp, *head = NULL;
struct utmp usr;
struct tm *ltm;
time_t prev_secs, secs, ut_timecopy;
int day, rfound, tchanged, tskipped;
day = -1;
prev_secs = 1; /* Minimum acceptable date == 1970 */
rfound = tchanged = tskipped = 0;
secs = 0;
while (fread((char *)&usr, sizeof(usr), 1, fp) == 1) {
rfound++;
/*
* The type of utmp.ut_time is not necessary type time_t, as
* it is explicitly defined as type int32_t. Copy the value
* for platforms where sizeof(time_t) != size(int32_t).
*/
ut_timecopy = _time32_to_time(usr.ut_time);
/*
* With sparc64 using 64-bit time_t's, there is some system
* routine which sets ut_time==0 (the high-order word of a
* 64-bit time) instead of a 32-bit time value. For those
* wtmp files, it is "more-accurate" to substitute the most-
* recent time found, instead of throwing away the entire
* record. While it is still just a guess, it is a better
* guess than throwing away a log-off record and therefore
* counting a session as if it continued to the end of the
* month, or the next system-reboot.
*/
if (ut_timecopy == 0 && prev_secs > 1) {
#ifdef DEBUG
if (Debug)
printf("%s - date changed to: %s",
debug_pfx(&usr, &usr), ctime(&prev_secs));
#endif
tchanged++;
usr.ut_time = ut_timecopy = prev_secs;
}
/*
* Skip records where the time goes backwards.
*/
if (ut_timecopy < prev_secs) {
#ifdef DEBUG
if (Debug)
printf("%s - bad date, record skipped\n",
debug_pfx(&usr, &usr));
#endif
tskipped++;
continue; /* Skip this invalid record. */
}
prev_secs = ut_timecopy;
if (!FirstTime)
FirstTime = ut_timecopy;
if (Flags & AC_D) {
ltm = localtime(&ut_timecopy);
if (day >= 0 && day != ltm->tm_yday) {
day = ltm->tm_yday;
/*
* print yesterday's total
*/
secs = ut_timecopy;
secs -= ltm->tm_sec;
secs -= 60 * ltm->tm_min;
secs -= 3600 * ltm->tm_hour;
show_today(Users, head, secs);
} else
day = ltm->tm_yday;
}
switch(*usr.ut_line) {
case '|':
secs = ut_timecopy;
break;
case '{':
secs -= ut_timecopy;
/*
* adjust time for those logged in
*/
for (lp = head; lp != NULL; lp = lp->next)
lp->usr.ut_time -= secs;
break;
case '~': /* reboot or shutdown */
head = log_out(head, &usr);
FirstTime = ut_timecopy; /* shouldn't be needed */
break;
default:
/*
* if they came in on tty[p-sP-S]*, then it is only
* a login session if the ut_host field is non-empty
*/
if (*usr.ut_name) {
if (strncmp(usr.ut_line, "tty", 3) == 0 ||
strchr("pqrsPQRS", usr.ut_line[3]) != 0 ||
*usr.ut_host != '\0')
head = log_in(head, &usr);
#ifdef DEBUG
else if (Debug > 1)
/* Things such as 'screen' sessions. */
printf("%s - record ignored\n",
debug_pfx(&usr, &usr));
#endif
} else
head = log_out(head, &usr);
break;
}
}
(void)fclose(fp);
if (!(Flags & AC_W))
usr.ut_time = time((time_t *)0);
(void)strcpy(usr.ut_line, "~");
if (Flags & AC_D) {
ut_timecopy = _time32_to_time(usr.ut_time);
ltm = localtime(&ut_timecopy);
if (day >= 0 && day != ltm->tm_yday) {
/*
* print yesterday's total
*/
secs = ut_timecopy;
secs -= ltm->tm_sec;
secs -= 60 * ltm->tm_min;
secs -= 3600 * ltm->tm_hour;
show_today(Users, head, secs);
}
}
/*
* anyone still logged in gets time up to now
*/
head = log_out(head, &usr);
if (Flags & AC_D)
show_today(Users, head, time((time_t *)0));
else {
if (Flags & AC_P)
show_users(Users);
show("total", Total);
}
if (tskipped > 0)
printf("(Skipped %d of %d records due to invalid time values)\n",
tskipped, rfound);
if (tchanged > 0)
printf("(Changed %d of %d records to have a more likely time value)\n",
tchanged, rfound);
return 0;
}
void
usage(void)
{
(void)fprintf(stderr,
#ifdef CONSOLE_TTY
"ac [-dp] [-c console] [-t tty] [-w wtmp] [users ...]\n");
#else
"ac [-dp] [-t tty] [-w wtmp] [users ...]\n");
#endif
exit(1);
}