diff options
| -rw-r--r-- | src/cowboy_static.erl | 247 |
1 files changed, 160 insertions, 87 deletions
diff --git a/src/cowboy_static.erl b/src/cowboy_static.erl index cf44920..d583fa9 100644 --- a/src/cowboy_static.erl +++ b/src/cowboy_static.erl @@ -32,10 +32,10 @@ %% under and the path to a directory to read files from. The request path prefix %% is defined in the path pattern of the cowboy dispatch rule for the handler. %% The request path pattern must end with a `...' token. +%% %% The directory path can be set to either an absolute or relative path in the %% form of a list or binary string representation of a file system path. A list -%% of binary path segments, as is used throughout cowboy, is also a valid -%% directory path. +%% of binary path segments is also a valid directory path. %% %% The directory path can also be set to a relative path within the `priv/' %% directory of an application. This is configured by setting the value of the @@ -213,21 +213,23 @@ init({_Transport, http}, _Req, _Opts) -> -spec rest_init(Req, list()) -> {ok, Req, #state{}} when Req::cowboy_req:req(). rest_init(Req, Opts) -> {_, DirectoryOpt} = lists:keyfind(directory, 1, Opts), - Directory = directory_path(DirectoryOpt), + Directory = fullpath(filename:absname(directory_path(DirectoryOpt))), case lists:keyfind(file, 1, Opts) of false -> - {Filepath, Req2} = cowboy_req:path_info(Req), - case check_path(Filepath) of - ok -> - Filepath2 = join_paths(Directory, Filepath), - rest_init(Req2, Opts, Filepath2); - error -> + {PathInfo, Req2} = cowboy_req:path_info(Req), + Filepath = filename:join([Directory|PathInfo]), + Len = byte_size(Directory), + case fullpath(Filepath) of + << Directory:Len/binary, $/, _/binary >> -> + rest_init(Req2, Opts, Filepath); + _ -> {ok, Req2, #state{filepath=error, fileinfo=error, mimetypes=undefined, etag_fun=undefined}} end; {_, FileOpt} -> - Filepath = join_paths(Directory, filepath_path(FileOpt)), - rest_init(Req, Opts, Filepath) + Filepath = filepath_path(FileOpt), + Filepath2 = << Directory/binary, $/, Filepath/binary >>, + rest_init(Req, Opts, Filepath2) end. rest_init(Req, Opts, Filepath) -> @@ -327,66 +329,58 @@ file_contents(Req, #state{filepath=Filepath, end, {{stream, Filesize, Writefile}, Req, State}. +%% Internal. + -spec directory_path(dirspec()) -> dirpath(). directory_path({priv_dir, App, []}) -> priv_dir_path(App); -directory_path({priv_dir, App, [H|_]=Path}) when is_integer(H) -> - filename:join(priv_dir_path(App), Path); directory_path({priv_dir, App, [H|_]=Path}) when is_binary(H) -> - filename:join(filename:split(priv_dir_path(App)) ++ Path); -directory_path({priv_dir, App, Path}) when is_binary(Path) -> + filename:join(priv_dir_path(App), filename:join(Path)); +directory_path({priv_dir, App, Path}) -> filename:join(priv_dir_path(App), Path); -directory_path(Path) -> - Path. - -%% @private Ensure that a file path is of the same type as a request path. --spec filepath_path(dirpath()) -> Path::[binary()]. -filepath_path([H|_]=Path) when is_integer(H) -> - filename:split(list_to_binary(Path)); -filepath_path(Path) when is_binary(Path) -> - filename:split(Path); -filepath_path([H|_]=Path) when is_binary(H) -> +directory_path([H|_]=Path) when is_binary(H) -> + filename:join(Path); +directory_path([H|_]=Path) when is_integer(H) -> + list_to_binary(Path); +directory_path(Path) when is_binary(Path) -> Path. -%% @private Validate a request path for unsafe characters. -%% There is no way to escape special characters in a filesystem path. --spec check_path(Path::[binary()]) -> ok | error. -check_path([]) -> ok; -check_path([<<"">>|_T]) -> error; -check_path([<<".">>|_T]) -> error; -check_path([<<"..">>|_T]) -> error; -check_path([H|T]) -> - case binary:match(H, <<"/">>) of - {_, _} -> error; - nomatch -> check_path(T) - end. - -%% @private Join the the directory and request paths. --spec join_paths(dirpath(), [binary()]) -> binary(). -join_paths([H|_]=Dirpath, Filepath) when is_integer(H) -> - filename:join(filename:split(Dirpath) ++ Filepath); -join_paths([H|_]=Dirpath, Filepath) when is_binary(H) -> - filename:join(Dirpath ++ Filepath); -join_paths(Dirpath, Filepath) when is_binary(Dirpath) -> - filename:join([Dirpath] ++ Filepath); -join_paths([], Filepath) -> - filename:join(Filepath). - %% @private Return the path to the priv/ directory of an application. -spec priv_dir_path(atom()) -> string(). priv_dir_path(App) -> case code:priv_dir(App) of {error, bad_name} -> priv_dir_mod(App); - Dir -> Dir + Dir -> list_to_binary(Dir) end. -spec priv_dir_mod(atom()) -> string(). priv_dir_mod(Mod) -> case code:which(Mod) of - File when not is_list(File) -> "../priv"; - File -> filename:join([filename:dirname(File),"../priv"]) + File when not is_list(File) -> <<"../priv">>; + File -> filename:join(filename:dirname(File), <<"../priv">>) end. +%% @private Ensure that a file path is of the same type as a request path. +filepath_path(Path) when is_binary(Path) -> + Path; +filepath_path([H|_]=Path) when is_binary(H) -> + filename:join(Path); +filepath_path([H|_]=Path) when is_integer(H) -> + list_to_binary(Path). + +fullpath(Path) when is_binary(Path) -> + fullpath(filename:split(Path), []). +fullpath([], Acc) -> + filename:join(lists:reverse(Acc)); +fullpath([<<".">>|Tail], Acc) -> + fullpath(Tail, Acc); +fullpath([<<"..">>|Tail], Acc=[_]) -> + fullpath(Tail, Acc); +fullpath([<<"..">>|Tail], [_|Acc]) -> + fullpath(Tail, Acc); +fullpath([Segment|Tail], Acc) -> + fullpath(Tail, [Segment|Acc]). + %% @private Use application/octet-stream as the default mimetype. %% If a list of extension - mimetype pairs are provided as the mimetypes %% an attempt to find the mimetype using the file extension. If no match @@ -430,44 +424,123 @@ attr_etag_function(Args, Attrs) -> -include_lib("eunit/include/eunit.hrl"). -define(_eq(E, I), ?_assertEqual(E, I)). -check_path_test_() -> - C = fun check_path/1, - [?_eq(error, C([<<>>])), - ?_eq(ok, C([<<"abc">>])), - ?_eq(error, C([<<".">>])), - ?_eq(error, C([<<"..">>])), - ?_eq(error, C([<<"/">>])) - ]. - -join_paths_test_() -> - P = fun join_paths/2, - [?_eq(<<"a">>, P([], [<<"a">>])), - ?_eq(<<"a/b/c">>, P(<<"a/b">>, [<<"c">>])), - ?_eq(<<"a/b/c">>, P("a/b", [<<"c">>])), - ?_eq(<<"a/b/c">>, P([<<"a">>, <<"b">>], [<<"c">>])) - ]. - directory_path_test_() -> - P = fun directory_path/1, - PL = fun(I) -> length(filename:split(P(I))) end, + PL = fun(D) -> length(filename:split(directory_path(D))) end, Base = PL({priv_dir, cowboy, []}), - [?_eq(Base + 1, PL({priv_dir, cowboy, "a"})), - ?_eq(Base + 1, PL({priv_dir, cowboy, <<"a">>})), - ?_eq(Base + 1, PL({priv_dir, cowboy, [<<"a">>]})), - ?_eq(Base + 2, PL({priv_dir, cowboy, "a/b"})), - ?_eq(Base + 2, PL({priv_dir, cowboy, <<"a/b">>})), - ?_eq(Base + 2, PL({priv_dir, cowboy, [<<"a">>, <<"b">>]})), - ?_eq("a/b", P("a/b")) - ]. + LengthTests = [ + Base + 1, {priv_dir, cowboy, "a"}, + Base + 1, {priv_dir, cowboy, <<"a">>}, + Base + 1, {priv_dir, cowboy, [<<"a">>]}, + Base + 2, {priv_dir, cowboy, "a/b"}, + Base + 2, {priv_dir, cowboy, <<"a/b">>}, + Base + 2, {priv_dir, cowboy, [<<"a">>, <<"b">>]} + ], + TypeTests = [ + {priv_dir, cowboy, []}, + {priv_dir, cowboy, "a"}, + {priv_dir, cowboy, <<"a">>}, + {priv_dir, cowboy, [<<"a">>]}, + "a", + <<"a">>, + [<<"a">>] + ], + [{lists:flatten(io_lib:format("~p", [D])), + fun() -> R = PL(D) end} || {R, D} <- LengthTests] + ++ [{lists:flatten(io_lib:format("~p", [D])), + fun() -> is_binary(directory_path(D)) end} || D <- TypeTests]. filepath_path_test_() -> - P = fun filepath_path/1, - [?_eq([<<"a">>], P("a")), - ?_eq([<<"a">>], P(<<"a">>)), - ?_eq([<<"a">>], P([<<"a">>])), - ?_eq([<<"a">>, <<"b">>], P("a/b")), - ?_eq([<<"a">>, <<"b">>], P(<<"a/b">>)), - ?_eq([<<"a">>, <<"b">>], P([<<"a">>, <<"b">>])) - ]. + Tests = [ + {<<"a">>, "a"}, + {<<"a">>, <<"a">>}, + {<<"a">>, [<<"a">>]}, + {<<"a/b">>, "a/b"}, + {<<"a/b">>, <<"a/b">>}, + {<<"a/b">>, [<<"a">>, <<"b">>]} + ], + [{lists:flatten(io_lib:format("~p", [F])), + fun() -> R = filepath_path(F) end} || {R, F} <- Tests]. + +fullpath_test_() -> + Tests = [ + {<<"/home/cowboy">>, <<"/home/cowboy">>}, + {<<"/home/cowboy">>, <<"/home/cowboy/">>}, + {<<"/home/cowboy">>, <<"/home/cowboy/./">>}, + {<<"/home/cowboy">>, <<"/home/cowboy/./././././.">>}, + {<<"/home/cowboy">>, <<"/home/cowboy/abc/..">>}, + {<<"/home/cowboy">>, <<"/home/cowboy/abc/../">>}, + {<<"/home/cowboy">>, <<"/home/cowboy/abc/./../.">>}, + {<<"/">>, <<"/home/cowboy/../../../../../..">>}, + {<<"/etc/passwd">>, <<"/home/cowboy/../../etc/passwd">>} + ], + [{P, fun() -> R = fullpath(P) end} || {R, P} <- Tests]. + +good_path_check_test_() -> + Tests = [ + <<"/home/cowboy/file">>, + <<"/home/cowboy/file/">>, + <<"/home/cowboy/./file">>, + <<"/home/cowboy/././././././file">>, + <<"/home/cowboy/abc/../file">>, + <<"/home/cowboy/abc/../file">>, + <<"/home/cowboy/abc/./.././file">> + ], + [{P, fun() -> + case fullpath(P) of + << "/home/cowboy/", _/binary >> -> ok + end + end} || P <- Tests]. + +bad_path_check_test_() -> + Tests = [ + <<"/home/cowboy/../../../../../../file">>, + <<"/home/cowboy/../../etc/passwd">> + ], + [{P, fun() -> + error = case fullpath(P) of + << "/home/cowboy/", _/binary >> -> ok; + _ -> error + end + end} || P <- Tests]. + +good_path_win32_check_test_() -> + Tests = case os:type() of + {unix, _} -> + []; + {win32, _} -> + [ + <<"c:/home/cowboy/file">>, + <<"c:/home/cowboy/file/">>, + <<"c:/home/cowboy/./file">>, + <<"c:/home/cowboy/././././././file">>, + <<"c:/home/cowboy/abc/../file">>, + <<"c:/home/cowboy/abc/../file">>, + <<"c:/home/cowboy/abc/./.././file">> + ] + end, + [{P, fun() -> + case fullpath(P) of + << "c:/home/cowboy/", _/binary >> -> ok + end + end} || P <- Tests]. + +bad_path_win32_check_test_() -> + Tests = case os:type() of + {unix, _} -> + []; + {win32, _} -> + [ + <<"c:/home/cowboy/../../secretfile.bat">>, + <<"c:/home/cowboy/c:/secretfile.bat">>, + <<"c:/home/cowboy/..\\..\\secretfile.bat">>, + <<"c:/home/cowboy/c:\\secretfile.bat">> + ] + end, + [{P, fun() -> + error = case fullpath(P) of + << "c:/home/cowboy/", _/binary >> -> ok; + _ -> error + end + end} || P <- Tests]. -endif. |