mtproto_proxy/test/prop_mtp_codec.erl

224 lines
8.1 KiB
Erlang

%% @doc Property-based tests for mtp_codec
-module(prop_mtp_codec).
-include_lib("proper/include/proper.hrl").
-include_lib("stdlib/include/assert.hrl").
-export([prop_obfuscated_secure_stream/1,
prop_obfuscated_secure_duplex/1,
prop_obfuscated_secure_duplex_multi/1,
prop_fullcbc_stream/1,
prop_tls_stream/1,
prop_tls_big_stream/1]).
prop_obfuscated_secure_stream(doc) ->
"Tests that any number of packets can be encrypted and decrypted with codec that includes"
" combination of mtp_obfuscated and mtp_secure".
prop_obfuscated_secure_stream() ->
?FORALL({Key, Iv, Stream}, stream_arg_set(), obfuscated_secure_stream(Key, Iv, Stream)).
stream_arg_set() ->
proper_types:tuple(
[mtp_prop_gen:key(),
mtp_prop_gen:iv(),
mtp_prop_gen:stream_4b()
]).
obfuscated_secure_stream(Key, Iv, Stream) ->
Codec0 = mk_secure_codec(Key, Iv, Key, Iv),
{BinStream, Codec2} =
lists:foldl(
fun(Bin, {Acc, Codec1}) ->
{Data, Codec2} = mtp_codec:encode_packet(Bin, Codec1),
{<<Acc/binary, (iolist_to_binary(Data))/binary>>,
Codec2}
end, {<<>>, Codec0}, Stream),
{ResStream, _Codec3} = parse_stream(BinStream, Codec2),
?assertEqual(Stream, ResStream),
true.
prop_obfuscated_secure_duplex(doc) ->
"Tests that any number of packets can be encrypted and decrypted in both directions using"
" a pair of keys with codec that uses combination of mtp_obfuscated and mtp_secure".
prop_obfuscated_secure_duplex() ->
?FORALL({TxKey, TxIv, RxKey, RxIv, Stream}, duplex_arg_set(),
obfuscated_secure_duplex(TxKey, TxIv, RxKey, RxIv, Stream)).
duplex_arg_set() ->
{mtp_prop_gen:key(),
mtp_prop_gen:iv(),
mtp_prop_gen:key(),
mtp_prop_gen:iv(),
mtp_prop_gen:stream_4b()}.
obfuscated_secure_duplex(TxKey, TxIv, RxKey, RxIv, Stream) ->
CliCodec0 = mk_secure_codec(TxKey, TxIv, RxKey, RxIv),
SrvCodec0 = mk_secure_codec(RxKey, RxIv, TxKey, TxIv),
{_, _, BackStream} = roundtrip(CliCodec0, SrvCodec0, Stream),
Stream == BackStream.
prop_obfuscated_secure_duplex_multi(doc) ->
"Tests that any number of packets can be encrypted and decrypted in both directions multiple"
" times using a pair of keys with codec that uses combination of mtp_obfuscated and"
" mtp_secure".
prop_obfuscated_secure_duplex_multi() ->
?FORALL({N, {TxKey, TxIv, RxKey, RxIv, Stream}}, {proper_types:range(1, 100), duplex_arg_set()},
obfuscated_secure_duplex_multi(N, TxKey, TxIv, RxKey, RxIv, Stream)).
obfuscated_secure_duplex_multi(N, TxKey, TxIv, RxKey, RxIv, Stream0) ->
CliCodec0 = mk_secure_codec(TxKey, TxIv, RxKey, RxIv),
SrvCodec0 = mk_secure_codec(RxKey, RxIv, TxKey, TxIv),
{_, _, Stream} =
lists:foldl(
fun(I, {CliCodec1, SrvCodec1, Stream1}) ->
{_, _, BackStream} = Res = roundtrip(CliCodec1, SrvCodec1, Stream1),
?assertEqual(Stream0, BackStream, [{trip_i, I}]),
Res
end, {CliCodec0, SrvCodec0, Stream0}, lists:seq(1, N)),
Stream0 == Stream.
%% Helpers
roundtrip(CliCodec0, SrvCodec0, Stream) ->
%% Client creates a stream of bytes
{CliBinStream, CliCodec1} =
lists:foldl(
fun(Bin, {Acc, Codec1}) ->
{Data, Codec2} = mtp_codec:encode_packet(Bin, Codec1),
{<<Acc/binary, (iolist_to_binary(Data))/binary>>,
Codec2}
end, {<<>>, CliCodec0}, Stream),
%% Server decodes stream of bytes and immediately "sends" them back
{ok, SrvBinStream, SrvCodec1} =
mtp_codec:fold_packets(
fun(Decoded, Acc, Codec1) ->
{Encoded, Codec2} = mtp_codec:encode_packet(Decoded, Codec1),
{<<Acc/binary, (iolist_to_binary(Encoded))/binary>>, Codec2}
end, <<>>, CliBinStream, SrvCodec0),
%% Client "receives" and decodes what server sent
{ok, RevCliDecodedStream, CliCodec2} =
mtp_codec:fold_packets(
fun(Decoded, Acc, Codec1) ->
{[Decoded | Acc], Codec1}
end, [], SrvBinStream, CliCodec1),
{CliCodec2, SrvCodec1, lists:reverse(RevCliDecodedStream)}.
mk_secure_codec(EncKey, EncIv, DecKey, DecIv) ->
Crypto = mtp_obfuscated:new(EncKey, EncIv, DecKey, DecIv),
Packet = mtp_secure:new(),
mtp_codec:new(mtp_obfuscated, Crypto,
mtp_secure, Packet).
prop_fullcbc_stream(doc) ->
"Tests that any number of packets can be encrypted and decrypted with mtp_full + mtp_aes_cbc"
" It emulates downstream codec set".
prop_fullcbc_stream() ->
?FORALL({Key, Iv, Stream}, fullcbc_arg_set(), fullcbc_stream(Key, Iv, Stream)).
fullcbc_arg_set() ->
proper_types:tuple(
[mtp_prop_gen:key(),
mtp_prop_gen:iv(),
mtp_prop_gen:stream_16b()
]).
fullcbc_stream(Key, Iv, Stream) ->
Codec0 = mk_fullcbc_codec(Key, Iv, Key, Iv),
{BinStream, Codec2} =
lists:foldl(
fun(Bin, {Acc, Codec1}) ->
{Data, Codec2} = mtp_codec:encode_packet(Bin, Codec1),
{<<Acc/binary, (iolist_to_binary(Data))/binary>>,
Codec2}
end, {<<>>, Codec0}, Stream),
{ResStream, Codec3} = parse_stream(BinStream, Codec2),
?assertEqual(Stream, ResStream, #{codec => Codec3}),
true.
mk_fullcbc_codec(EncKey, EncIv, DecKey, DecIv) ->
Crypto = mtp_aes_cbc:new(EncKey, EncIv, DecKey, DecIv, 16),
Packet = mtp_full:new(1, 1, true),
mtp_codec:new(mtp_aes_cbc, Crypto,
mtp_full, Packet).
prop_tls_stream(doc) ->
"Tests combination of fake-tls + mtp_obfuscated + mtp_secure. It emulates fake-tls client".
prop_tls_stream() ->
?FORALL({Key, Iv, Stream}, stream_arg_set(), tls_obfuscated_secure_stream(Key, Iv, Stream)).
prop_tls_big_stream(doc) ->
"Tests combination of fake-tls + mtp_obfuscated + mtp_secure with packets >64kb. "
"So, single 'packet-layer' packet will be split to multiple TLS packets. "
"It emulates file uppload with fake-tls client".
prop_tls_big_stream() ->
?FORALL({Key, Iv, Stream}, tls_big_stream_arg_set(), tls_obfuscated_secure_stream(Key, Iv, Stream)).
tls_big_stream_arg_set() ->
%% Packets more than 2^14b but less than 128kb
Min = 16 * 1024 + 10,
Max = 128 * 1024,
proper_types:tuple(
[mtp_prop_gen:key(),
mtp_prop_gen:iv(),
proper_types:list(mtp_prop_gen:aligned_binary(4, Min, Max))
]).
tls_obfuscated_secure_stream(Key, Iv, Stream) ->
Codec0 = mk_tls_codec(Key, Iv, Key, Iv),
{BinStream, Codec2} =
lists:foldl(
fun(Bin, {Acc, Codec1}) ->
{Data, Codec2} = mtp_codec:encode_packet(Bin, Codec1),
{<<Acc/binary, (iolist_to_binary(Data))/binary>>,
Codec2}
end, {<<>>, Codec0}, Stream),
{ResStream, _Codec3} = parse_stream(BinStream, Codec2),
?assertEqual(Stream, ResStream),
true.
parse_stream(Bin, Codec0) ->
%% We want to split solid stream to smaller chunks to emulate network packet fragmentation
Chunks = split_stream(Bin),
{DecodedRev, Codec} =
lists:foldl(
fun(Chunk, {Acc1, Codec1}) ->
{ok, Acc3, Codec3} =
mtp_codec:fold_packets(
fun(Decoded, Acc2, Codec2) ->
{[Decoded | Acc2], Codec2}
end, Acc1, Chunk, Codec1),
{Acc3, Codec3}
end, {[], Codec0}, Chunks),
{lists:reverse(DecodedRev), Codec}.
mk_tls_codec(EncKey, EncIv, DecKey, DecIv) ->
Crypto = mtp_obfuscated:new(EncKey, EncIv, DecKey, DecIv),
Packet = mtp_secure:new(),
Tls = mtp_fake_tls:new(),
mtp_codec:new(mtp_obfuscated, Crypto,
mtp_secure, Packet,
true, Tls,
30 * 1024 * 1024).
split_stream(<<>>) -> [];
split_stream(Bin) when byte_size(Bin) < 4 -> [Bin];
split_stream(Bin) ->
%% TODO: should have deterministic seed for rand!
Size = rand:uniform(byte_size(Bin) div 2),
<<Chunk:Size/binary, Tail/binary>> = Bin,
[Chunk | split_stream(Tail)].