mpd/src/mapper.c
Max Kellermann f291876772 mapper: check for "." and ".."
Make map_directory_child_fs() refuse the names "." and "..".  This is
currently the interface where an attacker may inject a manipulated
path (through the "update" command).
2008-10-31 16:48:58 +01:00

163 lines
4.3 KiB
C

/* the Music Player Daemon (MPD)
* Copyright (C) 2008 Max Kellermann <max@duempel.org>
* This project's homepage is: http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Maps directory and song objects to file system paths.
*/
#include "mapper.h"
#include "directory.h"
#include "song.h"
#include "path.h"
#include "conf.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <glib.h>
static char *music_dir;
static size_t music_dir_length;
static char *playlist_dir;
static size_t playlist_dir_length;
void mapper_init(void)
{
ConfigParam *music_dir_param = parseConfigFilePath(CONF_MUSIC_DIR, 1);
ConfigParam *playlist_dir_param = parseConfigFilePath(CONF_PLAYLIST_DIR, 1);
int ret;
struct stat st;
music_dir = g_strdup(music_dir_param->value);
music_dir_length = strlen(music_dir);
ret = stat(music_dir, &st);
if (ret < 0)
g_warning("failed to stat music directory \"%s\" (config line %i): %s\n",
music_dir_param->value, music_dir_param->line,
strerror(errno));
else if (!S_ISDIR(st.st_mode))
g_warning("music directory is not a directory: \"%s\" (config line %i)\n",
music_dir_param->value, music_dir_param->line);
playlist_dir = g_strdup(playlist_dir_param->value);
playlist_dir_length = strlen(playlist_dir);
ret = stat(playlist_dir, &st);
if (ret < 0)
g_warning("failed to stat playlist directory \"%s\" (config line %i): %s\n",
playlist_dir_param->value, playlist_dir_param->line,
strerror(errno));
else if (!S_ISDIR(st.st_mode))
g_warning("playlist directory is not a directory: \"%s\" (config line %i)\n",
playlist_dir_param->value, playlist_dir_param->line);
}
void mapper_finish(void)
{
g_free(music_dir);
g_free(playlist_dir);
}
static char *
rmp2amp_r(char *dst, const char *rel_path)
{
pfx_dir(dst, rel_path, strlen(rel_path),
(const char *)music_dir, music_dir_length);
return dst;
}
const char *
map_directory_fs(const struct directory *directory, char *buffer)
{
const char *dirname = directory_get_path(directory);
if (isRootDirectory(dirname))
return music_dir;
return rmp2amp_r(buffer, utf8_to_fs_charset(buffer, dirname));
}
const char *
map_directory_child_fs(const struct directory *directory, const char *name,
char *buffer)
{
char buffer2[MPD_PATH_MAX];
const char *parent_fs;
/* check for invalid or unauthorized base names */
if (*name == 0 || strchr(name, '/') != NULL ||
strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
return NULL;
parent_fs = map_directory_fs(directory, buffer2);
if (parent_fs == NULL)
return NULL;
utf8_to_fs_charset(buffer, name);
pfx_dir(buffer, name, strlen(name),
parent_fs, strlen(parent_fs));
return buffer;
}
const char *
map_song_fs(const struct song *song, char *buffer)
{
assert(song_is_file(song));
if (song_in_database(song))
return map_directory_child_fs(song->parent, song->url, buffer);
else
return utf8_to_fs_charset(buffer, song->url);
}
const char *
map_fs_to_utf8(const char *path_fs, char *buffer)
{
if (strncmp(path_fs, music_dir, music_dir_length) == 0 &&
path_fs[music_dir_length] == '/')
/* remove musicDir prefix */
path_fs += music_dir_length + 1;
else if (path_fs[0] == '/')
/* not within musicDir */
return NULL;
return fs_charset_to_utf8(buffer, path_fs);
}
static char *rpp2app_r(char *dst, const char *rel_path)
{
pfx_dir(dst, rel_path, strlen(rel_path),
playlist_dir, playlist_dir_length);
return dst;
}
const char *
map_spl_path(void)
{
return playlist_dir;
}
const char *
map_spl_utf8_to_fs(const char *name, char *buffer)
{
rpp2app_r(buffer, utf8_to_fs_charset(buffer, name));
g_strlcat(buffer, "." PLAYLIST_FILE_SUFFIX, MPD_PATH_MAX);
return buffer;
}