From f556b69004ce0978944d0f1ce024f04b9130b53a Mon Sep 17 00:00:00 2001 From: =?utf8?q?R=C3=A9mi=20Denis-Courmont?= Date: Thu, 4 Jan 2007 16:37:21 +0000 Subject: [PATCH] Allow directory module to recurse through symbolic links as long as this does not cause infinite recursion. Also fix a few really minor ToCToU errors. --- include/vlc_charset.h | 2 + modules/access/directory.c | 167 +++++++++++++++++++++++-------------- src/libvlc.sym | 1 + src/text/unicode.c | 24 ++++-- 4 files changed, 127 insertions(+), 67 deletions(-) diff --git a/include/vlc_charset.h b/include/vlc_charset.h index 66f0d4f403..e9791719a2 100644 --- a/include/vlc_charset.h +++ b/include/vlc_charset.h @@ -38,10 +38,12 @@ VLC_EXPORT( char *, FromLocale, ( const char * ) ); VLC_EXPORT( char *, FromLocaleDup, ( const char * ) ); VLC_EXPORT( char *, ToLocale, ( const char * ) ); +/* TODO: move all of this to "vlc_fs.h" or something like that */ VLC_EXPORT( int, utf8_open, ( const char *filename, int flags, mode_t mode ) ); VLC_EXPORT( FILE *, utf8_fopen, ( const char *filename, const char *mode ) ); VLC_EXPORT( DIR *, utf8_opendir, ( const char *dirname ) ); VLC_EXPORT( char *, utf8_readdir, ( DIR *dir ) ); +VLC_EXPORT( int, utf8_loaddir, ( DIR *dir, char ***namelist, int (*select)( const char * ), int (*compar)( const char **, const char ** ) ) ); VLC_EXPORT( int, utf8_scandir, ( const char *dirname, char ***namelist, int (*select)( const char * ), int (*compar)( const char **, const char ** ) ) ); #ifdef WIN32 diff --git a/modules/access/directory.c b/modules/access/directory.c index 4334a1baba..e01fed287b 100644 --- a/modules/access/directory.c +++ b/modules/access/directory.c @@ -1,10 +1,11 @@ /***************************************************************************** * directory.c: expands a directory (directory: access plug-in) ***************************************************************************** - * Copyright (C) 2002-2004 the VideoLAN team + * Copyright (C) 2002-2007 the VideoLAN team * $Id$ * * Authors: Derk-Jan Hartman + * Rémi Denis-Courmont * * 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 @@ -114,9 +115,14 @@ vlc_module_end(); * Local prototypes, constants, structures *****************************************************************************/ -#define MODE_EXPAND 0 -#define MODE_COLLAPSE 1 -#define MODE_NONE 2 +enum +{ + MODE_EXPAND, + MODE_COLLAPSE, + MODE_NONE +}; + +typedef struct stat_list_t stat_list_t; static int Read( access_t *, uint8_t *, int ); static int ReadNull( access_t *, uint8_t *, int ); @@ -127,7 +133,10 @@ static int DemuxControl( demux_t *p_demux, int i_query, va_list args ); static int ReadDir( playlist_t *, const char *psz_name, int i_mode, - playlist_item_t *, playlist_item_t *, input_item_t * ); + playlist_item_t *, playlist_item_t *, input_item_t *, + DIR *handle, stat_list_t *stats ); + +static DIR *OpenDir (vlc_object_t *obj, const char *psz_name); /***************************************************************************** * Open: open the directory @@ -136,17 +145,12 @@ static int Open( vlc_object_t *p_this ) { access_t *p_access = (access_t*)p_this; - struct stat stat_info; - -#ifdef S_ISDIR - if (utf8_stat (p_access->psz_path, &stat_info) - || !S_ISDIR (stat_info.st_mode)) -#else - if( strcmp( p_access->psz_access, "dir") && - strcmp( p_access->psz_access, "directory") ) -#endif + DIR *handle = OpenDir (p_this, p_access->psz_path); + if (handle == NULL) return VLC_EGENERIC; + p_access->p_sys = (access_sys_t *)handle; + p_access->pf_read = Read; p_access->pf_block = NULL; p_access->pf_seek = NULL; @@ -163,6 +167,9 @@ static int Open( vlc_object_t *p_this ) *****************************************************************************/ static void Close( vlc_object_t * p_this ) { + access_t *p_access = (access_t*)p_this; + DIR *handle = (DIR *)p_access->p_sys; + closedir (handle); } /***************************************************************************** @@ -224,8 +231,6 @@ static int Read( access_t *p_access, uint8_t *p_buffer, int i_len) i_mode = MODE_EXPAND; free( psz ); - msg_Dbg( p_access, "opening directory `%s'", p_access->psz_path ); - p_current->p_input->i_type = ITEM_TYPE_DIRECTORY; p_item_in_category = playlist_ItemToNode( p_playlist, p_current, VLC_FALSE ); @@ -235,7 +240,7 @@ static int Read( access_t *p_access, uint8_t *p_buffer, int i_len) DIRECTORY_ACTIVITY ); ReadDir( p_playlist, psz_name, i_mode, p_current, p_item_in_category, - p_current_input ); + p_current_input, (DIR *)p_access->p_sys, NULL ); i_activity = var_GetInteger( p_playlist, "activity" ); var_SetInteger( p_playlist, "activity", i_activity - @@ -334,13 +339,21 @@ static int Sort (const char **a, const char **b) return strcoll (*a, *b); } +struct stat_list_t +{ + stat_list_t *parent; + struct stat st; +}; + + /***************************************************************************** * ReadDir: read a directory and add its content to the list *****************************************************************************/ static int ReadDir( playlist_t *p_playlist, const char *psz_name, int i_mode, playlist_item_t *p_parent, playlist_item_t *p_parent_category, - input_item_t *p_current_input ) + input_item_t *p_current_input, + DIR *handle, stat_list_t *stparent ) { char **pp_dir_content = NULL; int i_dir_content, i, i_return = VLC_SUCCESS; @@ -350,17 +363,48 @@ static int ReadDir( playlist_t *p_playlist, const char *psz_name, int i_extensions = 0; char *psz_ignore; + struct stat_list_t stself; + int fd = dirfd (handle); + + if ((fd == -1) || fstat (fd, &stself.st)) + { + msg_Err (p_playlist, "cannot stat `%s': %s", psz_name, + strerror (errno)); + return VLC_EGENERIC; + } + + for (stat_list_t *stats = stparent; stats != NULL; stats = stats->parent) + { +#ifndef WIN32 + if ((stself.st.st_ino == stats->st.st_ino) + && (stself.st.st_dev == stats->st.st_dev)) + { + msg_Warn (p_playlist, + "ignoring infinitely recursive directory `%s'", + psz_name); + return VLC_SUCCESS; + } +#else + /* Windows has st_dev (driver letter - 'A'), but it zeroes st_ino, + * so that the test above will always incorrectly succeed. */ +#endif + } + + stself.parent = stparent; + /* Get the first directory entry */ - i_dir_content = utf8_scandir (psz_name, &pp_dir_content, NULL, Sort); + i_dir_content = utf8_loaddir (handle, &pp_dir_content, NULL, Sort); if( i_dir_content == -1 ) { - msg_Warn( p_playlist, "failed to read directory" ); + msg_Err (p_playlist, "cannot read `%s': %s", psz_name, + strerror (errno)); return VLC_EGENERIC; } else if( i_dir_content <= 0 ) { /* directory is empty */ - if( pp_dir_content ) free( pp_dir_content ); + msg_Dbg( p_playlist, "%s directory is empty", psz_name ); + free( pp_dir_content ); return VLC_SUCCESS; } @@ -407,53 +451,33 @@ static int ReadDir( playlist_t *p_playlist, const char *psz_name, /* if it starts with '.' then forget it */ if (entry[0] != '.') { -#if defined( S_ISDIR ) - struct stat stat_data; + DIR *subdir = (i_mode != MODE_COLLAPSE) + ? OpenDir (VLC_OBJECT (p_playlist), psz_uri) : NULL; - if (!utf8_stat (psz_uri, &stat_data) - && S_ISDIR(stat_data.st_mode) && i_mode != MODE_COLLAPSE ) -#else - if( 0 ) -#endif + if (subdir != NULL) /* Recurse into subdirectory */ { -#if defined( S_ISLNK ) -/* - * FIXME: there is a ToCToU race condition here; but it is rather tricky - * impossible to fix while keeping some kind of portable code, and maybe even - * in a non-portable way. - */ - if (utf8_lstat (psz_uri, &stat_data) - || S_ISLNK(stat_data.st_mode) ) - { - msg_Dbg( p_playlist, "skipping directory symlink %s", - psz_uri ); - continue; - } -#endif if( i_mode == MODE_NONE ) { - msg_Dbg( p_playlist, "skipping subdirectory %s", psz_uri ); + msg_Dbg( p_playlist, "skipping subdirectory `%s'", + psz_uri ); + closedir (subdir); continue; } - else if( i_mode == MODE_EXPAND ) - { - msg_Dbg(p_playlist, "creading subdirectory %s", psz_uri ); - - p_node = playlist_NodeCreate( p_playlist, entry, - p_parent_category, - PLAYLIST_NO_REBUILD ); - - /* If we had the parent in category, the it is now node. - * Else, we still don't have */ - if( ReadDir( p_playlist, psz_uri , MODE_EXPAND, - p_node, p_parent_category ? p_node : NULL, - p_current_input ) - != VLC_SUCCESS ) - { - i_return = VLC_EGENERIC; - break; - } - } + + msg_Dbg (p_playlist, "creating subdirectory %s", psz_uri); + + p_node = playlist_NodeCreate( p_playlist, entry, + p_parent_category, + PLAYLIST_NO_REBUILD ); + + /* If we had the parent in category, the it is now node. + * Else, we still don't have */ + i_return = ReadDir( p_playlist, psz_uri , MODE_EXPAND, + p_node, p_parent_category ? p_node : NULL, + p_current_input, subdir, &stself ); + closedir (subdir); + if (i_return) + break; // error :-( } else { @@ -507,3 +531,22 @@ static int ReadDir( playlist_t *p_playlist, const char *psz_name, return i_return; } + + +static DIR *OpenDir (vlc_object_t *obj, const char *path) +{ + msg_Dbg (obj, "opening directory `%s'", path); + DIR *handle = utf8_opendir (path); + if (handle == NULL) + { + int err = errno; + if (err != ENOTDIR) + msg_Err (obj, "%s: %s", path, strerror (err)); + else + msg_Dbg (obj, "skipping non-directory `%s'", path); + errno = err; + + return NULL; + } + return handle; +} diff --git a/src/libvlc.sym b/src/libvlc.sym index 17743819ef..5fef698c4d 100644 --- a/src/libvlc.sym +++ b/src/libvlc.sym @@ -302,6 +302,7 @@ utf8_mkdir utf8_open utf8_opendir utf8_readdir +utf8_loaddir utf8_scandir utf8_stat utf8_vfprintf diff --git a/src/text/unicode.c b/src/text/unicode.c index 7979a44e3b..10a103bc3c 100644 --- a/src/text/unicode.c +++ b/src/text/unicode.c @@ -496,12 +496,10 @@ static int dummy_select( const char *str ) return 1; } -int utf8_scandir( const char *dirname, char ***namelist, +int utf8_loaddir( DIR *dir, char ***namelist, int (*select)( const char * ), int (*compar)( const char **, const char ** ) ) { - DIR *dir = utf8_opendir( dirname ); - if( select == NULL ) select = dummy_select; @@ -513,6 +511,8 @@ int utf8_scandir( const char *dirname, char ***namelist, char *entry; unsigned num = 0; + rewinddir( dir ); + while( ( entry = utf8_readdir( dir ) ) != NULL ) { char **newtab; @@ -532,7 +532,6 @@ int utf8_scandir( const char *dirname, char ***namelist, tab = newtab; tab[num++] = entry; } - closedir( dir ); if( compar != NULL ) qsort( tab, num, sizeof( tab[0] ), @@ -548,10 +547,25 @@ int utf8_scandir( const char *dirname, char ***namelist, free( tab[i] ); if( tab != NULL ) free( tab ); - return -1;} + } } + return -1; } +int utf8_scandir( const char *dirname, char ***namelist, + int (*select)( const char * ), + int (*compar)( const char **, const char ** ) ) +{ + DIR *dir = utf8_opendir (dirname); + int val = -1; + + if (dir != NULL) + { + val = utf8_loaddir (dir, namelist, select, compar); + closedir (dir); + } + return val; +} static int utf8_statEx( const char *filename, struct stat *buf, vlc_bool_t deref ) -- 2.39.2