#include <config.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#include <unistd.h>
#include <errno.h>
#include "sudo.h"
#include "sudo_plugin.h"
#include "sudo_plugin_int.h"
#include "sudo_dso.h"
#define SUDOERS_PLUGIN "sudoers.so"
#ifdef _PATH_SUDO_PLUGIN_DIR
static int
sudo_stat_plugin(struct plugin_info *info, char *fullpath,
size_t pathsize, struct stat *sb)
{
int status = -1;
debug_decl(sudo_stat_plugin, SUDO_DEBUG_PLUGIN)
if (info->path[0] == '/') {
if (strlcpy(fullpath, info->path, pathsize) >= pathsize) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("%s: %s"), info->path, strerror(ENAMETOOLONG));
goto done;
}
status = stat(fullpath, sb);
} else {
int len;
#ifdef STATIC_SUDOERS_PLUGIN
if (strcmp(info->path, SUDOERS_PLUGIN) == 0) {
if (strlcpy(fullpath, info->path, pathsize) >= pathsize) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("%s: %s"), info->path, strerror(ENAMETOOLONG));
goto done;
}
memset(sb, 0, sizeof(*sb));
sb->st_uid = ROOT_UID;
sb->st_mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH;
status = 0;
goto done;
}
#endif
if (sudo_conf_plugin_dir_path() == NULL) {
errno = ENOENT;
goto done;
}
len = snprintf(fullpath, pathsize, "%s%s", sudo_conf_plugin_dir_path(),
info->path);
if (len <= 0 || (size_t)len >= pathsize) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("%s%s: %s"), sudo_conf_plugin_dir_path(), info->path,
strerror(ENAMETOOLONG));
goto done;
}
if ((status = stat(fullpath, sb)) != 0) {
char *cp = strrchr(fullpath, '/');
if (cp > fullpath + 4 && cp[-5] == '/' && cp[-4] == 's' &&
cp[-3] == 'u' && cp[-2] == 'd' && cp[-1] == 'o') {
int serrno = errno;
strlcpy(cp - 4, info->path, pathsize - (cp - 4 - fullpath));
if ((status = stat(fullpath, sb)) != 0)
errno = serrno;
}
}
}
done:
debug_return_int(status);
}
static bool
sudo_check_plugin(struct plugin_info *info, char *fullpath, size_t pathsize)
{
struct stat sb;
bool rval = false;
debug_decl(sudo_check_plugin, SUDO_DEBUG_PLUGIN)
if (sudo_stat_plugin(info, fullpath, pathsize, &sb) != 0) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warn("%s%s",
sudo_conf_plugin_dir_path() ? sudo_conf_plugin_dir_path() : "",
info->path);
goto done;
}
if (sb.st_uid != ROOT_UID) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("%s must be owned by uid %d"), fullpath, ROOT_UID);
goto done;
}
if ((sb.st_mode & (S_IWGRP|S_IWOTH)) != 0) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("%s must be only be writable by owner"), fullpath);
goto done;
}
rval = true;
done:
debug_return_bool(rval);
}
#else
static bool
sudo_check_plugin(struct plugin_info *info, char *fullpath, size_t pathsize)
{
debug_decl(sudo_check_plugin, SUDO_DEBUG_PLUGIN)
(void)strlcpy(fullpath, info->path, pathsize);
debug_return_bool(true);
}
#endif
static bool
sudo_load_plugin(struct plugin_container *policy_plugin,
struct plugin_container_list *io_plugins, struct plugin_info *info)
{
struct plugin_container *container = NULL;
struct generic_plugin *plugin;
char path[PATH_MAX];
void *handle = NULL;
debug_decl(sudo_load_plugin, SUDO_DEBUG_PLUGIN)
if (!sudo_check_plugin(info, path, sizeof(path)))
goto bad;
handle = sudo_dso_load(path, SUDO_DSO_LAZY|SUDO_DSO_GLOBAL);
if (!handle) {
const char *errstr = sudo_dso_strerror();
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("unable to load %s: %s"), path,
errstr ? errstr : "unknown error");
goto bad;
}
plugin = sudo_dso_findsym(handle, info->symbol_name);
if (!plugin) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("unable to find symbol `%s' in %s"), info->symbol_name, path);
goto bad;
}
if (plugin->type != SUDO_POLICY_PLUGIN && plugin->type != SUDO_IO_PLUGIN) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("unknown policy type %d found in %s"), plugin->type, path);
goto bad;
}
if (SUDO_API_VERSION_GET_MAJOR(plugin->version) != SUDO_API_VERSION_MAJOR) {
sudo_warnx(U_("error in %s, line %d while loading plugin `%s'"),
_PATH_SUDO_CONF, info->lineno, info->symbol_name);
sudo_warnx(U_("incompatible plugin major version %d (expected %d) found in %s"),
SUDO_API_VERSION_GET_MAJOR(plugin->version),
SUDO_API_VERSION_MAJOR, path);
goto bad;
}
if (plugin->type == SUDO_POLICY_PLUGIN) {
if (policy_plugin->handle != NULL) {
if (strcmp(policy_plugin->name, info->symbol_name) != 0) {
sudo_warnx(U_("ignoring policy plugin `%s' in %s, line %d"),
info->symbol_name, _PATH_SUDO_CONF, info->lineno);
sudo_warnx(U_("only a single policy plugin may be specified"));
goto bad;
}
sudo_warnx(U_("ignoring duplicate policy plugin `%s' in %s, line %d"),
info->symbol_name, _PATH_SUDO_CONF, info->lineno);
goto bad;
}
if (handle != NULL) {
policy_plugin->handle = handle;
policy_plugin->path = strdup(path);
if (policy_plugin->path == NULL) {
sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
goto bad;
}
policy_plugin->name = info->symbol_name;
policy_plugin->options = info->options;
policy_plugin->debug_instance = SUDO_DEBUG_INSTANCE_INITIALIZER;
policy_plugin->u.generic = plugin;
policy_plugin->debug_files = sudo_conf_debug_files(path);
}
} else if (plugin->type == SUDO_IO_PLUGIN) {
TAILQ_FOREACH(container, io_plugins, entries) {
if (strcmp(container->name, info->symbol_name) == 0) {
sudo_warnx(U_("ignoring duplicate I/O plugin `%s' in %s, line %d"),
info->symbol_name, _PATH_SUDO_CONF, info->lineno);
sudo_dso_unload(handle);
handle = NULL;
break;
}
}
if (handle != NULL) {
container = calloc(1, sizeof(*container));
if (container == NULL || (container->path = strdup(path)) == NULL) {
sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
goto bad;
}
container->handle = handle;
container->name = info->symbol_name;
container->options = info->options;
container->debug_instance = SUDO_DEBUG_INSTANCE_INITIALIZER;
container->u.generic = plugin;
policy_plugin->debug_files = sudo_conf_debug_files(path);
TAILQ_INSERT_TAIL(io_plugins, container, entries);
}
}
info->symbol_name = NULL;
info->options = NULL;
debug_return_bool(true);
bad:
free(container);
if (handle != NULL)
sudo_dso_unload(handle);
debug_return_bool(false);
}
static void
free_plugin_info(struct plugin_info *info)
{
free(info->path);
free(info->options);
free(info->symbol_name);
free(info);
}
bool
sudo_load_plugins(struct plugin_container *policy_plugin,
struct plugin_container_list *io_plugins)
{
struct plugin_container *container;
struct plugin_info_list *plugins;
struct plugin_info *info, *next;
bool rval = false;
debug_decl(sudo_load_plugins, SUDO_DEBUG_PLUGIN)
plugins = sudo_conf_plugins();
TAILQ_FOREACH_SAFE(info, plugins, entries, next) {
rval = sudo_load_plugin(policy_plugin, io_plugins, info);
if (!rval)
goto done;
free_plugin_info(info);
}
TAILQ_INIT(plugins);
if (policy_plugin->handle == NULL) {
info = calloc(1, sizeof(*info));
if (info == NULL) {
sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
goto done;
}
info->symbol_name = "sudoers_policy";
info->path = SUDOERS_PLUGIN;
rval = sudo_load_plugin(policy_plugin, io_plugins, info);
free(info);
if (!rval)
goto done;
if (TAILQ_EMPTY(io_plugins)) {
info = calloc(1, sizeof(*info));
if (info == NULL) {
sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
goto done;
}
info->symbol_name = "sudoers_io";
info->path = SUDOERS_PLUGIN;
rval = sudo_load_plugin(policy_plugin, io_plugins, info);
free(info);
if (!rval)
goto done;
}
}
if (policy_plugin->u.policy->check_policy == NULL) {
sudo_warnx(U_("policy plugin %s does not include a check_policy method"),
policy_plugin->name);
rval = false;
goto done;
}
sudo_debug_set_active_instance(SUDO_DEBUG_INSTANCE_INITIALIZER);
if (policy_plugin->u.policy->version >= SUDO_API_MKVERSION(1, 2)) {
if (policy_plugin->u.policy->register_hooks != NULL)
policy_plugin->u.policy->register_hooks(SUDO_HOOK_VERSION, register_hook);
}
TAILQ_FOREACH(container, io_plugins, entries) {
if (container->u.io->version >= SUDO_API_MKVERSION(1, 2)) {
if (container->u.io->register_hooks != NULL)
container->u.io->register_hooks(SUDO_HOOK_VERSION, register_hook);
}
}
sudo_debug_set_active_instance(sudo_debug_instance);
done:
debug_return_bool(rval);
}