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| author | Ingela Anderton Andin <[email protected]> | 2017-11-07 18:34:34 +0100 |
|---|---|---|
| committer | Ingela Anderton Andin <[email protected]> | 2017-11-09 16:29:38 +0100 |
| commit | 38b07caa2a1c6cd3537eadd36770afa54f067562 (patch) | |
| tree | 6ede98ba4f15f9cfdd46ad3ea31ddca4d0a28cdf | |
| parent | 3e8c1ff94c0a73df71daadd4eb782c21c49f22d9 (diff) | |
| download | otp-38b07caa2a1c6cd3537eadd36770afa54f067562.tar.gz otp-38b07caa2a1c6cd3537eadd36770afa54f067562.tar.bz2 otp-38b07caa2a1c6cd3537eadd36770afa54f067562.zip | |
ssl: Countermeasurements for Bleichenbacher attack
| -rw-r--r-- | lib/ssl/src/dtls_connection.erl | 1 | ||||
| -rw-r--r-- | lib/ssl/src/ssl_connection.erl | 21 | ||||
| -rw-r--r-- | lib/ssl/src/ssl_connection.hrl | 1 | ||||
| -rw-r--r-- | lib/ssl/src/tls_connection.erl | 1 |
4 files changed, 22 insertions, 2 deletions
diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl index ff3e69bae5..260ae8769c 100644 --- a/lib/ssl/src/dtls_connection.erl +++ b/lib/ssl/src/dtls_connection.erl @@ -644,6 +644,7 @@ handle_client_hello(#client_hello{client_version = ClientVersion} = Hello, State = prepare_flight(State0#state{connection_states = ConnectionStates, negotiated_version = Version, + client_hello_version = ClientVersion, hashsign_algorithm = HashSign, session = Session, negotiated_protocol = Protocol}), diff --git a/lib/ssl/src/ssl_connection.erl b/lib/ssl/src/ssl_connection.erl index b031d3d47b..b33ce63c32 100644 --- a/lib/ssl/src/ssl_connection.erl +++ b/lib/ssl/src/ssl_connection.erl @@ -1367,8 +1367,25 @@ server_certify_and_key_exchange(State0, Connection) -> request_client_cert(State2, Connection). certify_client_key_exchange(#encrypted_premaster_secret{premaster_secret= EncPMS}, - #state{private_key = Key} = State, Connection) -> - PremasterSecret = ssl_handshake:premaster_secret(EncPMS, Key), + #state{private_key = Key, client_hello_version = {Major, Minor} = Version} = State, Connection) -> + + %% Countermeasure for Bleichenbacher attack always provide some kind of premaster secret + %% and fail handshake later.RFC 5246 section 7.4.7.1. + PremasterSecret = + try ssl_handshake:premaster_secret(EncPMS, Key) of + Secret when erlang:byte_size(Secret) == ?NUM_OF_PREMASTERSECRET_BYTES -> + case Secret of + <<?BYTE(Major), ?BYTE(Minor), _/binary>> -> %% Correct + Secret; + <<?BYTE(_), ?BYTE(_), Rest/binary>> -> %% Version mismatch + <<?BYTE(Major), ?BYTE(Minor), Rest/binary>> + end; + _ -> %% erlang:byte_size(Secret) =/= ?NUM_OF_PREMASTERSECRET_BYTES + make_premaster_secret(Version, rsa) + catch + #alert{description = ?DECRYPT_ERROR} -> + make_premaster_secret(Version, rsa) + end, calculate_master_secret(PremasterSecret, State, Connection, certify, cipher); certify_client_key_exchange(#client_diffie_hellman_public{dh_public = ClientPublicDhKey}, diff --git a/lib/ssl/src/ssl_connection.hrl b/lib/ssl/src/ssl_connection.hrl index 3e26f67de1..f9d2149170 100644 --- a/lib/ssl/src/ssl_connection.hrl +++ b/lib/ssl/src/ssl_connection.hrl @@ -57,6 +57,7 @@ session_cache_cb :: atom(), crl_db :: term(), negotiated_version :: ssl_record:ssl_version() | 'undefined', + client_hello_version :: ssl_record:ssl_version() | 'undefined', client_certificate_requested = false :: boolean(), key_algorithm :: ssl_cipher:key_algo(), hashsign_algorithm = {undefined, undefined}, diff --git a/lib/ssl/src/tls_connection.erl b/lib/ssl/src/tls_connection.erl index e3ffbea3d3..7861287a22 100644 --- a/lib/ssl/src/tls_connection.erl +++ b/lib/ssl/src/tls_connection.erl @@ -286,6 +286,7 @@ hello(internal, #client_hello{client_version = ClientVersion} = Hello, gen_handshake(ssl_connection, hello, internal, {common_client_hello, Type, ServerHelloExt}, State#state{connection_states = ConnectionStates, negotiated_version = Version, + client_hello_version = ClientVersion, hashsign_algorithm = HashSign, session = Session, negotiated_protocol = Protocol}) |