261 lines
6.8 KiB
C
261 lines
6.8 KiB
C
/*-
|
|
* Copyright (c) 2002-2003 Networks Associates Technology, Inc.
|
|
* Copyright (c) 2004-2011 Dag-Erling Smørgrav
|
|
* All rights reserved.
|
|
*
|
|
* This software was developed for the FreeBSD Project by ThinkSec AS and
|
|
* Network Associates Laboratories, 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.
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
# include "config.h"
|
|
#endif
|
|
|
|
#include <sys/param.h>
|
|
|
|
#include <dlfcn.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include <security/pam_appl.h>
|
|
|
|
#include "openpam_impl.h"
|
|
#include "openpam_asprintf.h"
|
|
#include "openpam_ctype.h"
|
|
#include "openpam_dlfunc.h"
|
|
|
|
#ifndef RTLD_NOW
|
|
#define RTLD_NOW RTLD_LAZY
|
|
#endif
|
|
|
|
/*
|
|
* OpenPAM internal
|
|
*
|
|
* Perform sanity checks and attempt to load a module
|
|
*/
|
|
|
|
#ifdef HAVE_FDLOPEN
|
|
static void *
|
|
try_dlopen(const char *modfn)
|
|
{
|
|
void *dlh;
|
|
int fd;
|
|
|
|
openpam_log(PAM_LOG_LIBDEBUG, "dlopen(%s)", modfn);
|
|
if ((fd = open(modfn, O_RDONLY)) < 0) {
|
|
if (errno != ENOENT)
|
|
openpam_log(PAM_LOG_ERROR, "%s: %m", modfn);
|
|
return (NULL);
|
|
}
|
|
if (OPENPAM_FEATURE(VERIFY_MODULE_FILE) &&
|
|
openpam_check_desc_owner_perms(modfn, fd) != 0) {
|
|
close(fd);
|
|
return (NULL);
|
|
}
|
|
if ((dlh = fdlopen(fd, RTLD_NOW)) == NULL) {
|
|
openpam_log(PAM_LOG_ERROR, "%s: %s", modfn, dlerror());
|
|
close(fd);
|
|
errno = 0;
|
|
return (NULL);
|
|
}
|
|
close(fd);
|
|
return (dlh);
|
|
}
|
|
#else
|
|
static void *
|
|
try_dlopen(const char *modfn)
|
|
{
|
|
int check_module_file;
|
|
void *dlh;
|
|
|
|
openpam_log(PAM_LOG_LIBDEBUG, "dlopen(%s)", modfn);
|
|
openpam_get_feature(OPENPAM_VERIFY_MODULE_FILE,
|
|
&check_module_file);
|
|
if (check_module_file &&
|
|
openpam_check_path_owner_perms(modfn) != 0)
|
|
return (NULL);
|
|
if ((dlh = dlopen(modfn, RTLD_NOW)) == NULL) {
|
|
openpam_log(PAM_LOG_ERROR, "%s: %s", modfn, dlerror());
|
|
errno = 0;
|
|
return (NULL);
|
|
}
|
|
return (dlh);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Try to load a module from the suggested location.
|
|
*/
|
|
static pam_module_t *
|
|
try_module(const char *modpath)
|
|
{
|
|
const pam_module_t *dlmodule;
|
|
pam_module_t *module;
|
|
int i, serrno;
|
|
|
|
if ((module = calloc(1, sizeof *module)) == NULL ||
|
|
(module->path = strdup(modpath)) == NULL ||
|
|
(module->dlh = try_dlopen(modpath)) == NULL)
|
|
goto err;
|
|
dlmodule = dlsym(module->dlh, "_pam_module");
|
|
for (i = 0; i < PAM_NUM_PRIMITIVES; ++i) {
|
|
if (dlmodule) {
|
|
module->func[i] = dlmodule->func[i];
|
|
} else {
|
|
module->func[i] = (pam_func_t)dlfunc(module->dlh,
|
|
pam_sm_func_name[i]);
|
|
/*
|
|
* This openpam_log() call is a major source of
|
|
* log spam, and the cases that matter are caught
|
|
* and logged in openpam_dispatch(). This would
|
|
* be less problematic if dlerror() returned an
|
|
* error code so we could log an error only when
|
|
* dlfunc() failed for a reason other than "no
|
|
* such symbol".
|
|
*/
|
|
#if 0
|
|
if (module->func[i] == NULL)
|
|
openpam_log(PAM_LOG_LIBDEBUG, "%s: %s(): %s",
|
|
modpath, pam_sm_func_name[i], dlerror());
|
|
#endif
|
|
}
|
|
}
|
|
return (module);
|
|
err:
|
|
serrno = errno;
|
|
if (module != NULL) {
|
|
if (module->dlh != NULL)
|
|
dlclose(module->dlh);
|
|
if (module->path != NULL)
|
|
FREE(module->path);
|
|
FREE(module);
|
|
}
|
|
errno = serrno;
|
|
if (serrno != 0 && serrno != ENOENT)
|
|
openpam_log(PAM_LOG_ERROR, "%s: %m", modpath);
|
|
errno = serrno;
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* OpenPAM internal
|
|
*
|
|
* Locate a dynamically linked module
|
|
*/
|
|
|
|
pam_module_t *
|
|
openpam_dynamic(const char *modname)
|
|
{
|
|
pam_module_t *module;
|
|
char modpath[PATH_MAX];
|
|
const char **path, *p;
|
|
int has_so, has_ver;
|
|
int dot, len;
|
|
|
|
/*
|
|
* Simple case: module name contains path separator(s)
|
|
*/
|
|
if (strchr(modname, '/') != NULL) {
|
|
/*
|
|
* Absolute paths are not allowed if RESTRICT_MODULE_NAME
|
|
* is in effect (default off). Relative paths are never
|
|
* allowed.
|
|
*/
|
|
if (OPENPAM_FEATURE(RESTRICT_MODULE_NAME) ||
|
|
modname[0] != '/') {
|
|
openpam_log(PAM_LOG_ERROR,
|
|
"invalid module name: %s", modname);
|
|
return (NULL);
|
|
}
|
|
return (try_module(modname));
|
|
}
|
|
|
|
/*
|
|
* Check for .so and version sufixes
|
|
*/
|
|
p = strchr(modname, '\0');
|
|
has_ver = has_so = 0;
|
|
while (is_digit(*p))
|
|
--p;
|
|
if (*p == '.' && *++p != '\0') {
|
|
/* found a numeric suffix */
|
|
has_ver = 1;
|
|
/* assume that .so is either present or unneeded */
|
|
has_so = 1;
|
|
} else if (*p == '\0' && p >= modname + sizeof PAM_SOEXT &&
|
|
strcmp(p - sizeof PAM_SOEXT + 1, PAM_SOEXT) == 0) {
|
|
/* found .so suffix */
|
|
has_so = 1;
|
|
}
|
|
|
|
/*
|
|
* Complicated case: search for the module in the usual places.
|
|
*/
|
|
for (path = openpam_module_path; *path != NULL; ++path) {
|
|
/*
|
|
* Assemble the full path, including the version suffix. Take
|
|
* note of where the suffix begins so we can cut it off later.
|
|
*/
|
|
if (has_ver)
|
|
len = snprintf(modpath, sizeof modpath, "%s/%s%n",
|
|
*path, modname, &dot);
|
|
else if (has_so)
|
|
len = snprintf(modpath, sizeof modpath, "%s/%s%n.%d",
|
|
*path, modname, &dot, LIB_MAJ);
|
|
else
|
|
len = snprintf(modpath, sizeof modpath, "%s/%s%s%n.%d",
|
|
*path, modname, PAM_SOEXT, &dot, LIB_MAJ);
|
|
/* check for overflow */
|
|
if (len < 0 || (unsigned int)len >= sizeof modpath) {
|
|
errno = ENOENT;
|
|
continue;
|
|
}
|
|
/* try the versioned path */
|
|
if ((module = try_module(modpath)) != NULL)
|
|
return (module);
|
|
if (errno == ENOENT && modpath[dot] != '\0') {
|
|
/* no luck, try the unversioned path */
|
|
modpath[dot] = '\0';
|
|
if ((module = try_module(modpath)) != NULL)
|
|
return (module);
|
|
}
|
|
}
|
|
|
|
/* :( */
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* NOPARSE
|
|
*/
|