From b24651c3bb6fef59c0e92c24e69151d1a92c4b08 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=D0=A1=D0=B5=D1=80=D0=B3=D0=B5=D0=B9=20=D0=9F=D1=80=D0=BE?= =?UTF-8?q?=D1=85=D0=BE=D1=80=D0=BE=D0=B2?= Date: Mon, 19 Jan 2015 05:06:53 +0300 Subject: Add zlib limited output buffer size functionality This functionality may be useful for compressed streams with high compression ratio (in case of gzip it may be up to x1000), when small amount of compressed data will produce large amount of uncompressed output. This may lead to DoS attacks, because server easily goes out of memory. Example of such high compression ratio stream: ``` dd if=/dev/zero of=sparse.bin bs=1MB count=100 # 100mb of zeroes gzip sparse.bin # 95kb sparse.bin.gz $ erl > {ok, Compressed} = file:read_file("sparse.bin.gz"), > 97082 = size(Compressed), > Uncompressed = zlib:gunzip(Compressed), > 100000000 = iolist_size(Uncompressed). ``` --- lib/kernel/test/zlib_SUITE.erl | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) (limited to 'lib/kernel/test/zlib_SUITE.erl') diff --git a/lib/kernel/test/zlib_SUITE.erl b/lib/kernel/test/zlib_SUITE.erl index 3be6f39d95..e99151284f 100644 --- a/lib/kernel/test/zlib_SUITE.erl +++ b/lib/kernel/test/zlib_SUITE.erl @@ -82,7 +82,7 @@ groups() -> api_deflateSetDictionary, api_deflateReset, api_deflateParams, api_deflate, api_deflateEnd, api_inflateInit, api_inflateSetDictionary, - api_inflateSync, api_inflateReset, api_inflate, + api_inflateSync, api_inflateReset, api_inflate, api_inflateChunk, api_inflateEnd, api_setBufsz, api_getBufsz, api_crc32, api_adler32, api_getQSize, api_un_compress, api_un_zip, api_g_un_zip]}, @@ -357,6 +357,39 @@ api_inflate(Config) when is_list(Config) -> ?m({'EXIT',{data_error,_}}, zlib:inflate(Z1, <<2,1,2,1,2>>)), ?m(ok, zlib:close(Z1)). +api_inflateChunk(doc) -> "Test inflateChunk"; +api_inflateChunk(suite) -> []; +api_inflateChunk(Config) when is_list(Config) -> + ChunkSize = 1024, + Data = << <<(I rem 150)>> || I <- lists:seq(1, 3 * ChunkSize) >>, + Part1 = binary:part(Data, 0, ChunkSize), + Part2 = binary:part(Data, ChunkSize, ChunkSize), + Part3 = binary:part(Data, ChunkSize * 2, ChunkSize), + ?line Compressed = zlib:compress(Data), + ?line Z1 = zlib:open(), + ?line zlib:setBufSize(Z1, ChunkSize), + ?m(ok, zlib:inflateInit(Z1)), + ?m([], zlib:inflateChunk(Z1, <<>>)), + ?m({more, Part1}, zlib:inflateChunk(Z1, Compressed)), + ?m({more, Part2}, zlib:inflateChunk(Z1)), + ?m(Part3, zlib:inflateChunk(Z1)), + ?m(ok, zlib:inflateEnd(Z1)), + + ?m(ok, zlib:inflateInit(Z1)), + ?m({more, Part1}, zlib:inflateChunk(Z1, Compressed)), + + ?m(ok, zlib:inflateReset(Z1)), + + ?line zlib:setBufSize(Z1, size(Data)), + ?m(Data, zlib:inflateChunk(Z1, Compressed)), + ?m(ok, zlib:inflateEnd(Z1)), + + ?m(ok, zlib:inflateInit(Z1)), + ?m(?BARG, zlib:inflateChunk(gurka, Compressed)), + ?m(?BARG, zlib:inflateChunk(Z1, 4384)), + ?m({'EXIT',{data_error,_}}, zlib:inflateEnd(Z1)), + ?m(ok, zlib:close(Z1)). + api_inflateEnd(doc) -> "Test inflateEnd"; api_inflateEnd(suite) -> []; api_inflateEnd(Config) when is_list(Config) -> -- cgit v1.2.3