freebsd-dev/lib/libpam/modules/pam_chroot/pam_chroot.c
Pedro F. Giffuni 5e53a4f90f lib: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-26 02:00:33 +00:00

112 lines
3.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2003 Networks Associates Technology, 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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <pwd.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#define PAM_SM_SESSION
#include <security/pam_appl.h>
#include <security/pam_modules.h>
#include <security/openpam.h>
PAM_EXTERN int
pam_sm_open_session(pam_handle_t *pamh, int flags __unused,
int argc __unused, const char *argv[] __unused)
{
const char *dir, *end, *cwd, *user;
struct passwd *pwd;
char buf[PATH_MAX];
if (pam_get_user(pamh, &user, NULL) != PAM_SUCCESS ||
user == NULL || (pwd = getpwnam(user)) == NULL)
return (PAM_SESSION_ERR);
if (pwd->pw_uid == 0 && !openpam_get_option(pamh, "also_root"))
return (PAM_SUCCESS);
if (pwd->pw_dir == NULL)
return (PAM_SESSION_ERR);
if ((end = strstr(pwd->pw_dir, "/./")) != NULL) {
if (snprintf(buf, sizeof(buf), "%.*s",
(int)(end - pwd->pw_dir), pwd->pw_dir) > (int)sizeof(buf)) {
openpam_log(PAM_LOG_ERROR,
"%s's home directory is too long", user);
return (PAM_SESSION_ERR);
}
dir = buf;
cwd = end + 2;
} else if ((dir = openpam_get_option(pamh, "dir")) != NULL) {
if ((cwd = openpam_get_option(pamh, "cwd")) == NULL)
cwd = "/";
} else {
if (openpam_get_option(pamh, "always")) {
openpam_log(PAM_LOG_ERROR,
"%s has no chroot directory", user);
return (PAM_SESSION_ERR);
}
return (PAM_SUCCESS);
}
openpam_log(PAM_LOG_DEBUG, "chrooting %s to %s", dir, user);
if (chroot(dir) == -1) {
openpam_log(PAM_LOG_ERROR, "chroot(): %m");
return (PAM_SESSION_ERR);
}
if (chdir(cwd) == -1) {
openpam_log(PAM_LOG_ERROR, "chdir(): %m");
return (PAM_SESSION_ERR);
}
pam_setenv(pamh, "HOME", cwd, 1);
return (PAM_SUCCESS);
}
PAM_EXTERN int
pam_sm_close_session(pam_handle_t *pamh __unused, int flags __unused,
int argc __unused, const char *argv[] __unused)
{
return (PAM_SUCCESS);
}
PAM_MODULE_ENTRY("pam_chroot");