/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright 2001 Mark R V Murray
* All rights reserved.
* Copyright (c) 2001 Networks Associates Technology, Inc.
* All rights reserved.
*
* Portions of this software were 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>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <login_cap.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define PAM_SM_ACCOUNT
#include <security/pam_appl.h>
#include <security/pam_modules.h>
#include <security/pam_mod_misc.h>
#define _PATH_NOLOGIN "/var/run/nologin"
static char nologin_def[] = _PATH_NOLOGIN;
PAM_EXTERN int
pam_sm_acct_mgmt(pam_handle_t *pamh, int flags,
int argc __unused, const char *argv[] __unused)
{
login_cap_t *lc;
struct passwd *pwd;
struct stat st;
int retval, fd;
ssize_t ss;
const char *user, *nologin;
char *mtmp;
retval = pam_get_user(pamh, &user, NULL);
if (retval != PAM_SUCCESS)
return (retval);
PAM_LOG("Got user: %s", user);
pwd = getpwnam(user);
if (pwd == NULL)
return (PAM_USER_UNKNOWN);
/*
* login_getpwclass(3) will select the "root" class by default
* if pwd->pw_uid is 0. That class should have "ignorenologin"
* capability so that super-user can bypass nologin.
*/
lc = login_getpwclass(pwd);
if (lc == NULL) {
PAM_LOG("Unable to get login class for user %s", user);
return (PAM_SERVICE_ERR);
}
if (login_getcapbool(lc, "ignorenologin", 0)) {
login_close(lc);
return (PAM_SUCCESS);
}
nologin = login_getcapstr(lc, "nologin", nologin_def, nologin_def);
fd = open(nologin, O_RDONLY, 0);
if (fd < 0) {
login_close(lc);
return (PAM_SUCCESS);
}
PAM_LOG("Opened %s file", nologin);
if (fstat(fd, &st) == 0) {
mtmp = malloc(st.st_size + 1);
if (mtmp != NULL) {
ss = read(fd, mtmp, st.st_size);
if (ss > 0) {
mtmp[ss] = '\0';
pam_error(pamh, "%s", mtmp);
}
free(mtmp);
}
}
PAM_VERBOSE_ERROR("Administrator refusing you: %s", nologin);
close(fd);
login_close(lc);
return (PAM_AUTH_ERR);
}
PAM_MODULE_ENTRY("pam_nologin");
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