shadow/src/chgpasswd.c

494 lines
11 KiB
C

/*
* Copyright 1990 - 1994, Julianne Frances Haugh
* 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 Julianne F. Haugh 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 JULIE HAUGH 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 JULIE HAUGH 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 <getopt.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef USE_PAM
#include "pam_defs.h"
#endif /* USE_PAM */
#include "defines.h"
#include "nscd.h"
#include "prototypes.h"
#include "groupio.h"
#ifdef SHADOWGRP
#include "sgroupio.h"
#endif
/*
* Global variables
*/
static char *Prog;
static int cflg = 0;
static int eflg = 0;
static int md5flg = 0;
static int sflg = 0;
static const char *crypt_method = NULL;
static long sha_rounds = 5000;
#ifdef SHADOWGRP
static int is_shadow_grp;
#endif
#ifdef USE_PAM
static pam_handle_t *pamh = NULL;
#endif
/* local function prototypes */
static void usage (void);
static void process_flags (int argc, char **argv);
static void check_flags (void);
static void check_perms (void);
static void open_files (void);
static void close_files (void);
/*
* usage - display usage message and exit
*/
static void usage (void)
{
fprintf (stderr, _("Usage: %s [options]\n"
"\n"
"Options:\n"
" -c, --crypt-method the crypt method (one of %s)\n"
" -e, --encrypted supplied passwords are encrypted\n"
" -h, --help display this help message and exit\n"
" -m, --md5 encrypt the clear text password using\n"
" the MD5 algorithm\n"
"%s"
"\n"),
Prog,
#ifndef USE_SHA_CRYPT
"NONE DES MD5", ""
#else
"NONE DES MD5 SHA256 SHA512",
_(" -s, --sha-rounds number of SHA rounds for the SHA*\n"
" crypt algorithms\n")
#endif
);
exit (1);
}
/*
* 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 option_index = 0;
int c;
static struct option long_options[] = {
{"crypt-method", required_argument, NULL, 'c'},
{"encrypted", no_argument, NULL, 'e'},
{"help", no_argument, NULL, 'h'},
{"md5", no_argument, NULL, 'm'},
#ifdef USE_SHA_CRYPT
{"sha-rounds", required_argument, NULL, 's'},
#endif
{NULL, 0, NULL, '\0'}
};
while ((c = getopt_long (argc, argv,
#ifdef USE_SHA_CRYPT
"c:ehms:",
#else
"c:ehm",
#endif
long_options, &option_index)) != -1) {
switch (c) {
case 'c':
cflg = 1;
crypt_method = optarg;
break;
case 'e':
eflg = 1;
break;
case 'h':
usage ();
break;
case 'm':
md5flg = 1;
break;
#ifdef USE_SHA_CRYPT
case 's':
sflg = 1;
if (!getlong(optarg, &sha_rounds)) {
fprintf (stderr,
_("%s: invalid numeric argument '%s'\n"),
Prog, optarg);
usage ();
}
break;
#endif
case 0:
/* long option */
break;
default:
usage ();
break;
}
}
/* validate options */
check_flags ();
}
/*
* check_flags - check flags and parameters consistency
*
* It will not return if an error is encountered.
*/
static void check_flags (void)
{
if (sflg && !cflg) {
fprintf (stderr,
_("%s: %s flag is ONLY allowed with the %s flag\n"),
Prog, "-s", "-c");
usage ();
}
if ((eflg && (md5flg || cflg)) ||
(md5flg && cflg)) {
fprintf (stderr,
_("%s: the -c, -e, and -m flags are exclusive\n"),
Prog);
usage ();
}
if (cflg) {
if ( 0 != strcmp (crypt_method, "DES")
&& 0 != strcmp (crypt_method, "MD5")
&& 0 != strcmp (crypt_method, "NONE")
#ifdef USE_SHA_CRYPT
&& 0 != strcmp (crypt_method, "SHA256")
&& 0 != strcmp (crypt_method, "SHA512")
#endif
) {
fprintf (stderr,
_("%s: unsupported crypt method: %s\n"),
Prog, crypt_method);
usage ();
}
}
}
/*
* check_perms - check if the caller is allowed to add a group
*
* With PAM support, the setuid bit can be set on chgpasswd to allow
* non-root users to groups.
* Without PAM support, only users who can write in the group databases
* can add groups.
*
* It will not return if the user is not allowed.
*/
static void check_perms (void)
{
#ifdef USE_PAM
int retval = PAM_SUCCESS;
struct passwd *pampw;
pampw = getpwuid (getuid ()); /* local, no need for xgetpwuid */
if (pampw == NULL) {
retval = PAM_USER_UNKNOWN;
}
if (retval == PAM_SUCCESS) {
retval = pam_start ("chgpasswd", pampw->pw_name, &conv, &pamh);
}
if (retval == PAM_SUCCESS) {
retval = pam_authenticate (pamh, 0);
if (retval != PAM_SUCCESS) {
pam_end (pamh, retval);
}
}
if (retval == PAM_SUCCESS) {
retval = pam_acct_mgmt (pamh, 0);
if (retval != PAM_SUCCESS) {
pam_end (pamh, retval);
}
}
if (retval != PAM_SUCCESS) {
fprintf (stderr, _("%s: PAM authentication failed\n"), Prog);
exit (1);
}
#endif /* USE_PAM */
}
/*
* open_files - lock and open the group databases
*/
static void open_files (void)
{
/*
* Lock the group file and open it for reading and writing. This will
* bring all of the entries into memory where they may be updated.
*/
if (gr_lock () == 0) {
fprintf (stderr, _("%s: can't lock group file\n"), Prog);
exit (1);
}
if (gr_open (O_RDWR) == 0) {
fprintf (stderr, _("%s: can't open group file\n"), Prog);
gr_unlock ();
exit (1);
}
#ifdef SHADOWGRP
/* Do the same for the shadowed database, if it exist */
if (is_shadow_grp) {
if (sgr_lock () == 0) {
fprintf (stderr, _("%s: can't lock gshadow file\n"),
Prog);
gr_unlock ();
exit (1);
}
if (sgr_open (O_RDWR) == 0) {
fprintf (stderr, _("%s: can't open shadow file\n"),
Prog);
gr_unlock ();
sgr_unlock ();
exit (1);
}
}
#endif
}
/*
* close_files - close and unlock the group databases
*/
static void close_files (void)
{
#ifdef SHADOWGRP
if (is_shadow_grp) {
if (sgr_close () == 0) {
fprintf (stderr,
_("%s: error updating gshadow file\n"), Prog);
gr_unlock ();
exit (1);
}
sgr_unlock ();
}
#endif
if (gr_close () == 0) {
fprintf (stderr, _("%s: error updating group file\n"), Prog);
exit (1);
}
gr_unlock ();
}
int main (int argc, char **argv)
{
char buf[BUFSIZ];
char *name;
char *newpwd;
char *cp;
#ifdef SHADOWGRP
const struct sgrp *sg;
struct sgrp newsg;
#endif
const struct group *gr;
struct group newgr;
int errors = 0;
int line = 0;
int ok;
Prog = Basename (argv[0]);
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
process_flags(argc, argv);
check_perms ();
is_shadow_grp = sgr_file_present ();
open_files ();
/*
* Read each line, separating the group name from the password. The
* group entry for each group will be looked up in the appropriate
* file (gshadow or group) and the password changed.
*/
while (fgets (buf, sizeof buf, stdin) != (char *) 0) {
line++;
cp = strrchr (buf, '\n');
if (NULL != cp) {
*cp = '\0';
} else {
fprintf (stderr, _("%s: line %d: line too long\n"),
Prog, line);
errors++;
continue;
}
/*
* The group's name is the first field. It is separated from
* the password with a ":" character which is replaced with a
* NUL to give the new password. The new password will then
* be encrypted in the normal fashion with a new salt
* generated, unless the '-e' is given, in which case it is
* assumed to already be encrypted.
*/
name = buf;
cp = strchr (name, ':');
if (NULL != cp) {
*cp = '\0';
cp++;
} else {
fprintf (stderr,
_("%s: line %d: missing new password\n"),
Prog, line);
errors++;
continue;
}
newpwd = cp;
if (!eflg &&
(NULL == crypt_method ||
0 != strcmp(crypt_method, "NONE"))) {
void *arg = NULL;
if (md5flg) {
crypt_method = "MD5";
} else if (crypt_method != NULL) {
if (sflg) {
arg = &sha_rounds;
}
} else {
crypt_method = NULL;
}
cp = pw_encrypt (newpwd,
crypt_make_salt(crypt_method, arg));
}
/*
* Get the group file entry for this group. The group must
* already exist.
*/
gr = gr_locate (name);
if (NULL == gr) {
fprintf (stderr,
_("%s: line %d: unknown group %s\n"), Prog,
line, name);
errors++;
continue;
}
#ifdef SHADOWGRP
if (is_shadow_grp) {
sg = sgr_locate (name);
} else {
sg = NULL;
}
#endif
/*
* The freshly encrypted new password is merged into the
* group's entry.
*/
#ifdef SHADOWGRP
if (NULL != sg) {
newsg = *sg;
newsg.sg_passwd = cp;
} else
#endif
{
newgr = *gr;
newgr.gr_passwd = cp;
}
/*
* The updated group file entry is then put back and will
* be written to the group file later, after all the
* other entries have been updated as well.
*/
#ifdef SHADOWGRP
if (NULL != sg) {
ok = sgr_update (&newsg);
} else
#endif
{
ok = gr_update (&newgr);
}
if (!ok) {
fprintf (stderr,
_
("%s: line %d: cannot update group entry\n"),
Prog, line);
errors++;
continue;
}
}
/*
* Any detected errors will cause the entire set of changes to be
* aborted. Unlocking the group file will cause all of the
* changes to be ignored. Otherwise the file is closed, causing the
* changes to be written out all at once, and then unlocked
* afterwards.
*/
if (errors) {
fprintf (stderr,
_("%s: error detected, changes ignored\n"), Prog);
#ifdef SHADOWGRP
if (is_shadow_grp) {
sgr_unlock ();
}
#endif
gr_unlock ();
exit (1);
}
close_files ();
nscd_flush_cache ("group");
#ifdef USE_PAM
pam_end (pamh, PAM_SUCCESS);
#endif /* USE_PAM */
return (0);
}