Merge branch 'without-ec-cipher-suites' of git://github.com/KlausTrainer/ranch

1 files changed, 19 insertions, 1 deletions

diff --git a/src/ranch_ssl.erl b/src/ranch_ssl.erl
index 512f3b4..98b2f5e 100644
--- a/src/ranch_ssl.erl
+++ b/src/ranch_ssl.erl
@@ -136,10 +136,11 @@ listen(Opts) ->
 	true = lists:keymember(cert, 1, Opts)
 		orelse lists:keymember(certfile, 1, Opts),
 	Opts2 = ranch:set_option_default(Opts, backlog, 1024),
+	Opts3 = ranch:set_option_default(Opts2, ciphers, unbroken_cipher_suites()),
 	%% We set the port to 0 because it is given in the Opts directly.
 	%% The port in the options takes precedence over the one in the
 	%% first argument.
-	ssl:listen(0, ranch:filter_options(Opts2,
+	ssl:listen(0, ranch:filter_options(Opts3,
 		[backlog, cacertfile, cacerts, cert, certfile, ciphers,
 			fail_if_no_peer_cert, ip, key, keyfile, next_protocols_advertised,
 			nodelay, password, port, raw, reuse_session, reuse_sessions,
@@ -269,3 +270,20 @@ ssl_accept(Socket, Timeout) ->
 		{error, Reason} ->
 			{error, {ssl_accept, Reason}}
 	end.
+
+%% Unfortunately the implementation of elliptic-curve ciphers that has
+%% been introduced in R16B01 is incomplete.  Depending on the particular
+%% client, this can cause the TLS handshake to break during key
+%% agreement.  Depending on the ssl application version, this function
+%% returns a list of all cipher suites that are supported by default,
+%% minus the elliptic-curve ones.
+-spec unbroken_cipher_suites() -> [ssl:erl_cipher_suite()].
+unbroken_cipher_suites() ->
+	case proplists:get_value(ssl_app, ssl:versions()) of
+		"5.3" ->
+			lists:filter(fun(Suite) ->
+				string:left(atom_to_list(element(1, Suite)), 4) =/= "ecdh"
+			end, ssl:cipher_suites());
+		_ ->
+			ssl:cipher_suites()
+	end.