/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 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>
#define _BSD_SOURCE

#include <sys/param.h>
#include <sys/types.h>

#include <syslog.h>
#include <unistd.h>

#define PAM_SM_ACCOUNT

#include <security/pam_appl.h>
#include <security/pam_modules.h>
#include <security/pam_mod_misc.h>
#include <security/openpam.h>

#include "pam_login_access.h"

#define OPT_ACCESSFILE          "accessfile"
#define OPT_NOAUDIT             "noaudit"
#define OPT_FIELDSEP            "fieldsep"
#define OPT_LISTSEP             "listsep"
#define OPT_NODEFGROUP          "nodefgroup"

#define _PATH_LOGACCESS         "/etc/login.access"
#define _FIELD_SEPARATOR        ":"
#define _LIST_SEPARATOR         ", \t"

PAM_EXTERN int
pam_sm_acct_mgmt(pam_handle_t *pamh, int flags __unused,
    int argc __unused, const char *argv[] __unused)
{
        struct pam_login_access_options login_access_opts;
        const void *rhost, *tty, *user;
        char hostname[MAXHOSTNAMELEN];
        int pam_err;

        pam_err = pam_get_item(pamh, PAM_USER, &user);
        if (pam_err != PAM_SUCCESS)
                return (pam_err);

        if (user == NULL)
                return (PAM_SERVICE_ERR);

        PAM_LOG("Got user: %s", (const char *)user);

        pam_err = pam_get_item(pamh, PAM_RHOST, &rhost);
        if (pam_err != PAM_SUCCESS)
                return (pam_err);

        pam_err = pam_get_item(pamh, PAM_TTY, &tty);
        if (pam_err != PAM_SUCCESS)
                return (pam_err);

        gethostname(hostname, sizeof hostname);
        login_access_opts.defgroup = openpam_get_option(pamh, OPT_NODEFGROUP) == NULL ? true : false;
        login_access_opts.audit = openpam_get_option(pamh, OPT_NOAUDIT) == NULL ? true : false;
        if ((login_access_opts.accessfile = openpam_get_option(pamh, OPT_ACCESSFILE)) == NULL)
                login_access_opts.accessfile = _PATH_LOGACCESS;
        if ((login_access_opts.fieldsep = openpam_get_option(pamh, OPT_FIELDSEP)) == NULL)
                login_access_opts.fieldsep = _FIELD_SEPARATOR;
        if ((login_access_opts.listsep = openpam_get_option(pamh, OPT_LISTSEP)) == NULL)
                login_access_opts.listsep = _LIST_SEPARATOR;

        if (rhost != NULL && *(const char *)rhost != '\0') {
                PAM_LOG("Checking login.access for user %s from host %s",
                    (const char *)user, (const char *)rhost);
                if (login_access(user, rhost, &login_access_opts) != 0)
                        return (PAM_SUCCESS);
                PAM_VERBOSE_ERROR("%s is not allowed to log in from %s",
                    (const char *)user, (const char *)rhost);
        } else if (tty != NULL && *(const char *)tty != '\0') {
                PAM_LOG("Checking login.access for user %s on tty %s",
                    (const char *)user, (const char *)tty);
                if (login_access(user, tty, &login_access_opts) != 0)
                        return (PAM_SUCCESS);
                PAM_VERBOSE_ERROR("%s is not allowed to log in on %s",
                    (const char *)user, (const char *)tty);
        } else {
                PAM_LOG("Checking login.access for user %s",
                    (const char *)user);
                if (login_access(user, "***unknown***", &login_access_opts) != 0)
                        return (PAM_SUCCESS);
                PAM_VERBOSE_ERROR("%s is not allowed to log in",
                    (const char *)user);
        }

        return (PAM_AUTH_ERR);
}

PAM_MODULE_ENTRY("pam_login_access");