NetBSD/usr.bin/passwd/pam_passwd.c

150 lines
4.5 KiB
C

/* $NetBSD: pam_passwd.c,v 1.7 2021/09/10 21:52:18 rillig Exp $ */
/*-
* Copyright (c) 2002 Networks Associates Technologies, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by ThinkSec AS and
* NAI Labs, the Security Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* 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 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 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 AUTHOR 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 <sys/cdefs.h>
#ifdef __FreeBSD__
__FBSDID("$FreeBSD: src/usr.bin/passwd/passwd.c,v 1.23 2003/04/18 21:27:09 nectar Exp $");
#else
__RCSID("$NetBSD: pam_passwd.c,v 1.7 2021/09/10 21:52:18 rillig Exp $");
#endif
#include <sys/param.h>
#include <err.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <syslog.h>
#include <unistd.h>
#include "extern.h"
#include <security/pam_appl.h>
#include <security/openpam.h>
static pam_handle_t *pamh;
static struct pam_conv pamc = {
openpam_ttyconv,
NULL
};
#define pam_check(msg) \
do { \
if (pam_err != PAM_SUCCESS) { \
warnx("%s: %s", (msg), pam_strerror(pamh, pam_err)); \
goto end; \
} \
} while (0)
void
pwpam_process(const char *username, int argc, char **argv)
{
int ch, pam_err;
char hostname[MAXHOSTNAMELEN + 1];
/* details about the invoking user for logging */
const uid_t i_uid = getuid();
const struct passwd *const i_pwd = getpwuid(i_uid);
const char *const i_username = (i_pwd && i_pwd->pw_name)
? i_pwd->pw_name : "(null)";
while ((ch = getopt(argc, argv, "")) != -1) {
switch (ch) {
default:
usage();
/* NOTREACHED */
}
}
argc -= optind;
argv += optind;
switch (argc) {
case 0:
/* username already provided */
break;
case 1:
username = argv[0];
break;
default:
usage();
/* NOTREACHED */
}
(void)printf("Changing password for %s.\n", username);
/* initialize PAM -- always use the program name "passwd" */
pam_err = pam_start("passwd", username, &pamc, &pamh);
if (pam_err != PAM_SUCCESS)
errx(1, "unable to start PAM session: %s",
pam_strerror(NULL, pam_err));
pam_err = pam_set_item(pamh, PAM_TTY, ttyname(STDERR_FILENO));
pam_check("unable to set TTY");
(void)gethostname(hostname, sizeof hostname);
pam_err = pam_set_item(pamh, PAM_RHOST, hostname);
pam_check("unable to set RHOST");
pam_err = pam_set_item(pamh, PAM_RUSER, getlogin());
pam_check("unable to set RUSER");
/* set new password */
pam_err = pam_chauthtok(pamh, 0);
if (pam_err != PAM_SUCCESS) {
if (pam_err == PAM_PERM_DENIED) {
syslog(LOG_AUTH | LOG_NOTICE,
"user %s (UID %lu) failed to change the "
"PAM authentication token of user %s: %s",
i_username, (unsigned long)i_uid, username,
pam_strerror(pamh, pam_err));
}
printf("Unable to change auth token: %s\n",
pam_strerror(pamh, pam_err));
} else {
syslog(LOG_AUTH | LOG_INFO,
"user %s (UID %lu) successfully changed the "
"PAM authentication token of user %s",
i_username, (unsigned long)i_uid, username);
}
end:
pam_end(pamh, pam_err);
if (pam_err == PAM_SUCCESS)
return;
exit(1);
}