shadow/src/pwck.c
nekral-guest 27f67dcad0 * src/pwck.c: Unlock the password and shadow files when there is a
failure to prepare the update in memory.
2010-03-18 10:52:52 +00:00

856 lines
20 KiB
C

/*
* Copyright (c) 1992 - 1994, Julianne Frances Haugh
* Copyright (c) 1996 - 2000, Marek Michałkiewicz
* Copyright (c) 2001 , Michał Moskal
* Copyright (c) 2001 - 2006, Tomasz Kłoczko
* Copyright (c) 2007 - 2010, Nicolas François
* 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. The name of the copyright holders or contributors may not be used to
* endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* HOLDERS 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.
*/
#include <config.h>
#ident "$Id$"
#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
#include <stdio.h>
#include "chkname.h"
#include "commonio.h"
#include "defines.h"
#include "prototypes.h"
#include "pwio.h"
#include "shadowio.h"
#include "getdef.h"
#include "nscd.h"
#ifdef WITH_TCB
#include "tcbfuncs.h"
#endif /* WITH_TCB */
/*
* Exit codes
*/
/*@-exitarg@*/
#define E_OKAY 0
#define E_USAGE 1
#define E_BADENTRY 2
#define E_CANTOPEN 3
#define E_CANTLOCK 4
#define E_CANTUPDATE 5
#define E_CANTSORT 6
/*
* Global variables
*/
char *Prog;
static bool use_system_pw_file = true;
static bool use_system_spw_file = true;
static bool is_shadow = false;
static bool pw_opened = false;
static bool spw_opened = false;
static bool pw_locked = false;
static bool spw_locked = false;
/* Options */
static bool read_only = false;
static bool sort_mode = false;
static bool quiet = false; /* don't report warnings, only errors */
/* local function prototypes */
static void fail_exit (int code);
static void usage (void);
static void process_flags (int argc, char **argv);
static void open_files (void);
static void close_files (bool changed);
static void check_pw_file (int *errors, bool *changed);
static void check_spw_file (int *errors, bool *changed);
/*
* fail_exit - do some cleanup and exit with the given error code
*/
static void fail_exit (int code)
{
if (spw_locked) {
if (spw_unlock () == 0) {
fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, spw_dbname ());
if (use_system_spw_file) {
SYSLOG ((LOG_ERR, "failed to unlock %s",
spw_dbname ()));
}
/* continue */
}
}
if (pw_locked) {
if (pw_unlock () == 0) {
fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, pw_dbname ());
if (use_system_pw_file) {
SYSLOG ((LOG_ERR, "failed to unlock %s",
pw_dbname ()));
}
/* continue */
}
}
closelog ();
exit (code);
}
/*
* usage - print syntax message and exit
*/
static void usage (void)
{
#ifdef WITH_TCB
if (getdef_bool ("USE_TCB")) {
fprintf (stderr, _("Usage: %s [-q] [-r] [passwd]\n"),
Prog);
} else
#endif /* WITH_TCB */
{
fprintf (stderr,
_("Usage: %s [-q] [-r] [-s] [passwd [shadow]]\n"),
Prog);
}
exit (E_USAGE);
}
/*
* process_flags - parse the command line options
*
* It will not return if an error is encountered.
*/
static void process_flags (int argc, char **argv)
{
int arg;
/*
* Parse the command line arguments
*/
while ((arg = getopt (argc, argv, "eqrs")) != EOF) {
switch (arg) {
case 'e': /* added for Debian shadow-961025-2 compatibility */
case 'q':
quiet = true;
break;
case 'r':
read_only = true;
break;
case 's':
sort_mode = true;
break;
default:
usage ();
}
}
if (sort_mode && read_only) {
fprintf (stderr, _("%s: -s and -r are incompatible\n"), Prog);
exit (E_USAGE);
}
/*
* Make certain we have the right number of arguments
*/
if ((argc < optind) || (argc > (optind + 2))) {
usage ();
}
/*
* If there are two left over filenames, use those as the password
* and shadow password filenames.
*/
if (optind != argc) {
pw_setdbname (argv[optind]);
use_system_pw_file = false;
}
if ((optind + 2) == argc) {
#ifdef WITH_TCB
if (getdef_bool ("USE_TCB")) {
fprintf (stderr,
_("%s: no alternative shadow file allowed when USE_TCB is enabled.\n"),
Prog);
usage ();
}
#endif /* WITH_TCB */
spw_setdbname (argv[optind + 1]);
is_shadow = true;
use_system_spw_file = false;
} else if (optind == argc) {
is_shadow = spw_file_present ();
}
}
/*
* open_files - open the shadow database
*
* In read-only mode, the databases are not locked and are opened
* only for reading.
*/
static void open_files (void)
{
bool use_tcb = false;
#ifdef WITH_TCB
use_tcb = getdef_bool ("USE_TCB");
#endif /* WITH_TCB */
/*
* Lock the files if we aren't in "read-only" mode
*/
if (!read_only) {
if (pw_lock () == 0) {
fprintf (stderr,
_("%s: cannot lock %s; try again later.\n"),
Prog, pw_dbname ());
fail_exit (E_CANTLOCK);
}
pw_locked = true;
if (is_shadow && !use_tcb) {
if (spw_lock () == 0) {
fprintf (stderr,
_("%s: cannot lock %s; try again later.\n"),
Prog, spw_dbname ());
fail_exit (E_CANTLOCK);
}
spw_locked = true;
}
}
/*
* Open the files. Use O_RDONLY if we are in read_only mode, O_RDWR
* otherwise.
*/
if (pw_open (read_only ? O_RDONLY : O_RDWR) == 0) {
fprintf (stderr, _("%s: cannot open %s\n"),
Prog, pw_dbname ());
if (use_system_pw_file) {
SYSLOG ((LOG_WARN, "cannot open %s", pw_dbname ()));
}
fail_exit (E_CANTOPEN);
}
pw_opened = true;
if (is_shadow && !use_tcb) {
if (spw_open (read_only ? O_RDONLY : O_RDWR) == 0) {
fprintf (stderr, _("%s: cannot open %s\n"),
Prog, spw_dbname ());
if (use_system_spw_file) {
SYSLOG ((LOG_WARN, "cannot open %s",
spw_dbname ()));
}
fail_exit (E_CANTOPEN);
}
spw_opened = true;
}
}
/*
* close_files - close and unlock the password/shadow databases
*
* If changed is not set, the databases are not closed, and no
* changes are committed in the databases. The databases are
* unlocked anyway.
*/
static void close_files (bool changed)
{
/*
* All done. If there were no change we can just abandon any
* changes to the files.
*/
if (changed) {
if (pw_opened && pw_close () == 0) {
fprintf (stderr,
_("%s: failure while writing changes to %s\n"),
Prog, pw_dbname ());
if (use_system_pw_file) {
SYSLOG ((LOG_ERR,
"failure while writing changes to %s",
pw_dbname ()));
}
fail_exit (E_CANTUPDATE);
}
pw_opened = false;
if (is_shadow && spw_opened && (spw_close () == 0)) {
fprintf (stderr,
_("%s: failure while writing changes to %s\n"),
Prog, spw_dbname ());
if (use_system_spw_file) {
SYSLOG ((LOG_ERR,
"failure while writing changes to %s",
spw_dbname ()));
}
fail_exit (E_CANTUPDATE);
}
spw_opened = false;
}
/*
* Don't be anti-social - unlock the files when you're done.
*/
if (spw_locked) {
if (spw_unlock () == 0) {
fprintf (stderr,
_("%s: failed to unlock %s\n"),
Prog, spw_dbname ());
if (use_system_spw_file) {
SYSLOG ((LOG_ERR, "failed to unlock %s",
spw_dbname ()));
}
/* continue */
}
}
spw_locked = false;
if (pw_locked) {
if (pw_unlock () == 0) {
fprintf (stderr,
_("%s: failed to unlock %s\n"),
Prog, pw_dbname ());
if (use_system_pw_file) {
SYSLOG ((LOG_ERR, "failed to unlock %s",
pw_dbname ()));
}
/* continue */
}
}
pw_locked = false;
}
/*
* check_pw_file - check the content of the passwd file
*/
static void check_pw_file (int *errors, bool *changed)
{
struct commonio_entry *pfe, *tpfe;
struct passwd *pwd;
struct spwd *spw;
/*
* Loop through the entire password file.
*/
for (pfe = __pw_get_head (); NULL != pfe; pfe = pfe->next) {
/*
* If this is a NIS line, skip it. You can't "know" what NIS
* is going to do without directly asking NIS ...
*/
if (('+' == pfe->line[0]) || ('-' == pfe->line[0])) {
continue;
}
/*
* Start with the entries that are completely corrupt. They
* have no (struct passwd) entry because they couldn't be
* parsed properly.
*/
if (NULL == pfe->eptr) {
/*
* Tell the user this entire line is bogus and ask
* them to delete it.
*/
puts (_("invalid password file entry"));
printf (_("delete line '%s'? "), pfe->line);
*errors += 1;
/*
* prompt the user to delete the entry or not
*/
if (!yes_or_no (read_only)) {
continue;
}
/*
* All password file deletions wind up here. This
* code removes the current entry from the linked
* list. When done, it skips back to the top of the
* loop to try out the next list element.
*/
delete_pw:
if (use_system_pw_file) {
SYSLOG ((LOG_INFO, "delete passwd line '%s'",
pfe->line));
}
*changed = true;
__pw_del_entry (pfe);
continue;
}
/*
* Password structure is good, start using it.
*/
pwd = pfe->eptr;
/*
* Make sure this entry has a unique name.
*/
for (tpfe = __pw_get_head (); NULL != tpfe; tpfe = tpfe->next) {
const struct passwd *ent = tpfe->eptr;
/*
* Don't check this entry
*/
if (tpfe == pfe) {
continue;
}
/*
* Don't check invalid entries.
*/
if (NULL == ent) {
continue;
}
if (strcmp (pwd->pw_name, ent->pw_name) != 0) {
continue;
}
/*
* Tell the user this entry is a duplicate of
* another and ask them to delete it.
*/
puts (_("duplicate password entry"));
printf (_("delete line '%s'? "), pfe->line);
*errors += 1;
/*
* prompt the user to delete the entry or not
*/
if (yes_or_no (read_only)) {
goto delete_pw;
}
}
/*
* Check for invalid usernames. --marekm
*/
if (!is_valid_user_name (pwd->pw_name)) {
printf (_("invalid user name '%s'\n"), pwd->pw_name);
*errors += 1;
}
/*
* Check for invalid user ID.
*/
if (pwd->pw_uid == (uid_t)-1) {
printf (_("invalid user ID '%lu'\n"), (long unsigned int)pwd->pw_uid);
*errors += 1;
}
/*
* Make sure the primary group exists
*/
/* local, no need for xgetgrgid */
if (!quiet && (NULL == getgrgid (pwd->pw_gid))) {
/*
* No primary group, just give a warning
*/
printf (_("user '%s': no group %lu\n"),
pwd->pw_name, (unsigned long) pwd->pw_gid);
*errors += 1;
}
/*
* Make sure the home directory exists
*/
if (!quiet && (access (pwd->pw_dir, F_OK) != 0)) {
/*
* Home directory doesn't exist, give a warning
*/
printf (_("user '%s': directory '%s' does not exist\n"),
pwd->pw_name, pwd->pw_dir);
*errors += 1;
}
/*
* Make sure the login shell is executable
*/
if ( !quiet
&& ('\0' != pwd->pw_shell[0])
&& (access (pwd->pw_shell, F_OK) != 0)) {
/*
* Login shell doesn't exist, give a warning
*/
printf (_("user '%s': program '%s' does not exist\n"),
pwd->pw_name, pwd->pw_shell);
*errors += 1;
}
/*
* Make sure this entry exists in the /etc/shadow file.
*/
if (is_shadow) {
#ifdef WITH_TCB
if (getdef_bool ("USE_TCB")) {
if (shadowtcb_set_user (pwd->pw_name) == SHADOWTCB_FAILURE) {
printf (_("no tcb directory for %s\n"),
pwd->pw_name);
printf (_("create tcb directory for %s?"),
pwd->pw_name);
*errors += 1;
if (yes_or_no (read_only)) {
if (shadowtcb_create (pwd->pw_name, pwd->pw_uid) == SHADOWTCB_FAILURE) {
*errors += 1;
printf (_("failed to create tcb directory for %s\n"), pwd->pw_name);
continue;
}
} else {
continue;
}
}
if (spw_lock () == 0) {
*errors += 1;
fprintf (stderr,
_("%s: cannot lock %s.\n"),
Prog, spw_dbname ());
continue;
}
spw_locked = true;
if (spw_open (read_only ? O_RDONLY : O_RDWR) == 0) {
fprintf (stderr,
_("%s: cannot open %s\n"),
Prog, spw_dbname ());
*errors += 1;
if (spw_unlock () == 0) {
fprintf (stderr,
_("%s: failed to unlock %s\n"),
Prog, spw_dbname ());
if (use_system_spw_file) {
SYSLOG ((LOG_ERR,
"failed to unlock %s",
spw_dbname ()));
}
}
continue;
}
spw_opened = true;
}
#endif /* WITH_TCB */
spw = (struct spwd *) spw_locate (pwd->pw_name);
if (NULL == spw) {
printf (_("no matching password file entry in %s\n"),
spw_dbname ());
printf (_("add user '%s' in %s? "),
pwd->pw_name, spw_dbname ());
*errors += 1;
if (yes_or_no (read_only)) {
struct spwd sp;
struct passwd pw;
sp.sp_namp = pwd->pw_name;
sp.sp_pwdp = pwd->pw_passwd;
sp.sp_min =
getdef_num ("PASS_MIN_DAYS", -1);
sp.sp_max =
getdef_num ("PASS_MAX_DAYS", -1);
sp.sp_warn =
getdef_num ("PASS_WARN_AGE", -1);
sp.sp_inact = -1;
sp.sp_expire = -1;
sp.sp_flag = SHADOW_SP_FLAG_UNSET;
sp.sp_lstchg = (long) time ((time_t *) 0) / SCALE;
if (0 == sp.sp_lstchg) {
/* Better disable aging than
* requiring a password change
*/
sp.sp_lstchg = -1;
}
*changed = true;
if (spw_update (&sp) == 0) {
fprintf (stderr,
_("%s: failed to prepare the new %s entry '%s'\n"),
Prog, spw_dbname (), sp.sp_namp);
fail_exit (E_CANTUPDATE);
}
/* remove password from /etc/passwd */
pw = *pwd;
pw.pw_passwd = SHADOW_PASSWD_STRING; /* XXX warning: const */
if (pw_update (&pw) == 0) {
fprintf (stderr,
_("%s: failed to prepare the new %s entry '%s'\n"),
Prog, pw_dbname (), pw.pw_name);
fail_exit (E_CANTUPDATE);
}
}
} else {
/* The passwd entry has a shadow counterpart.
* Make sure no passwords are in passwd.
*/
if (strcmp (pwd->pw_passwd, SHADOW_PASSWD_STRING) != 0) {
printf (_("user %s has an entry in %s, but its password field in %s is not set to 'x'\n"),
pwd->pw_name, spw_dbname (), pw_dbname ());
*errors += 1;
}
}
}
#ifdef WITH_TCB
if (getdef_bool ("USE_TCB") && spw_locked) {
if (spw_opened && (spw_close () == 0)) {
fprintf (stderr,
_("%s: failure while writing changes to %s\n"),
Prog, spw_dbname ());
if (use_system_spw_file) {
SYSLOG ((LOG_ERR,
"failure while writing changes to %s",
spw_dbname ()));
}
} else {
spw_opened = false;
}
if (spw_unlock () == 0) {
fprintf (stderr,
_("%s: failed to unlock %s\n"),
Prog, spw_dbname ());
if (use_system_spw_file) {
SYSLOG ((LOG_ERR, "failed to unlock %s",
spw_dbname ()));
}
} else {
spw_locked = false;
}
}
#endif /* WITH_TCB */
}
}
/*
* check_spw_file - check the content of the shadowed password file (shadow)
*/
static void check_spw_file (int *errors, bool *changed)
{
struct commonio_entry *spe, *tspe;
struct spwd *spw;
/*
* Loop through the entire shadow password file.
*/
for (spe = __spw_get_head (); NULL != spe; spe = spe->next) {
/*
* Do not treat lines which were missing in shadow
* and were added earlier.
*/
if (NULL == spe->line) {
continue;
}
/*
* If this is a NIS line, skip it. You can't "know" what NIS
* is going to do without directly asking NIS ...
*/
if (('+' == spe->line[0]) || ('-' == spe->line[0])) {
continue;
}
/*
* Start with the entries that are completely corrupt. They
* have no (struct spwd) entry because they couldn't be
* parsed properly.
*/
if (NULL == spe->eptr) {
/*
* Tell the user this entire line is bogus and ask
* them to delete it.
*/
puts (_("invalid shadow password file entry"));
printf (_("delete line '%s'? "), spe->line);
*errors += 1;
/*
* prompt the user to delete the entry or not
*/
if (!yes_or_no (read_only)) {
continue;
}
/*
* All shadow file deletions wind up here. This code
* removes the current entry from the linked list.
* When done, it skips back to the top of the loop
* to try out the next list element.
*/
delete_spw:
if (use_system_spw_file) {
SYSLOG ((LOG_INFO, "delete shadow line '%s'",
spe->line));
}
*changed = true;
__spw_del_entry (spe);
continue;
}
/*
* Shadow password structure is good, start using it.
*/
spw = spe->eptr;
/*
* Make sure this entry has a unique name.
*/
for (tspe = __spw_get_head (); NULL != tspe; tspe = tspe->next) {
const struct spwd *ent = tspe->eptr;
/*
* Don't check this entry
*/
if (tspe == spe) {
continue;
}
/*
* Don't check invalid entries.
*/
if (NULL == ent) {
continue;
}
if (strcmp (spw->sp_namp, ent->sp_namp) != 0) {
continue;
}
/*
* Tell the user this entry is a duplicate of
* another and ask them to delete it.
*/
puts (_("duplicate shadow password entry"));
printf (_("delete line '%s'? "), spe->line);
*errors += 1;
/*
* prompt the user to delete the entry or not
*/
if (yes_or_no (read_only)) {
goto delete_spw;
}
}
/*
* Make sure this entry exists in the /etc/passwd
* file.
*/
if (pw_locate (spw->sp_namp) == NULL) {
/*
* Tell the user this entry has no matching
* /etc/passwd entry and ask them to delete it.
*/
printf (_("no matching password file entry in %s\n"),
pw_dbname ());
printf (_("delete line '%s'? "), spe->line);
*errors += 1;
/*
* prompt the user to delete the entry or not
*/
if (yes_or_no (read_only)) {
goto delete_spw;
}
}
/*
* Warn if last password change in the future. --marekm
*/
if ( !quiet
&& (spw->sp_lstchg > (long) time ((time_t *) 0) / SCALE)) {
printf (_("user %s: last password change in the future\n"),
spw->sp_namp);
*errors += 1;
}
}
}
/*
* pwck - verify password file integrity
*/
int main (int argc, char **argv)
{
int errors = 0;
bool changed = false;
/*
* Get my name so that I can use it to report errors.
*/
Prog = Basename (argv[0]);
(void) setlocale (LC_ALL, "");
(void) bindtextdomain (PACKAGE, LOCALEDIR);
(void) textdomain (PACKAGE);
OPENLOG ("pwck");
/* Parse the command line arguments */
process_flags (argc, argv);
open_files ();
if (sort_mode) {
if (pw_sort () != 0) {
fprintf (stderr,
_("%s: cannot sort entries in %s\n"),
Prog, pw_dbname ());
fail_exit (E_CANTSORT);
}
if (is_shadow) {
if (spw_sort () != 0) {
fprintf (stderr,
_("%s: cannot sort entries in %s\n"),
Prog, spw_dbname ());
fail_exit (E_CANTSORT);
}
}
changed = true;
} else {
check_pw_file (&errors, &changed);
if (is_shadow) {
check_spw_file (&errors, &changed);
}
}
close_files (changed);
nscd_flush_cache ("passwd");
/*
* Tell the user what we did and exit.
*/
if (0 != errors) {
printf (changed ?
_("%s: the files have been updated\n") :
_("%s: no changes\n"), Prog);
}
closelog ();
return ((0 != errors) ? E_BADENTRY : E_OKAY);
}