Merge branch 'ia/ssl/ECC-error-handling/OTP-11780'

* ia/ssl/ECC-error-handling/OTP-11780:
  ssl: Server now ignores client ECC curves that it does not support instead of crashing.
  Add test for unknown elliptic curve supported by client

3 files changed, 26 insertions, 3 deletions

diff --git a/lib/ssl/src/ssl_handshake.erl b/lib/ssl/src/ssl_handshake.erl
index 245cd3e280..74ca7ca699 100644
--- a/lib/ssl/src/ssl_handshake.erl
+++ b/lib/ssl/src/ssl_handshake.erl
@@ -1654,7 +1654,16 @@ dec_hello_extensions(<<?UINT16(?SIGNATURE_ALGORITHMS_EXT), ?UINT16(Len),
 dec_hello_extensions(<<?UINT16(?ELLIPTIC_CURVES_EXT), ?UINT16(Len),
 		       ExtData:Len/binary, Rest/binary>>, Acc) ->
     <<?UINT16(_), EllipticCurveList/binary>> = ExtData,
-    EllipticCurves = [tls_v1:enum_to_oid(X) || <<X:16>> <= EllipticCurveList],
+    %% Ignore unknown curves
+    Pick = fun(Enum) ->
+		   case tls_v1:enum_to_oid(Enum) of
+		       undefined ->
+			   false;
+		       Oid ->
+			   {true, Oid}
+		   end
+	   end,
+    EllipticCurves = lists:filtermap(Pick, [ECC || <<ECC:16>> <= EllipticCurveList]),
     dec_hello_extensions(Rest, Acc#hello_extensions{elliptic_curves =
 							#elliptic_curves{elliptic_curve_list =
 									     EllipticCurves}});
diff --git a/lib/ssl/src/tls_v1.erl b/lib/ssl/src/tls_v1.erl
index 7c7fdd64c3..7b1f53b969 100644
--- a/lib/ssl/src/tls_v1.erl
+++ b/lib/ssl/src/tls_v1.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2007-2013. All Rights Reserved.
+%% Copyright Ericsson AB 2007-2014. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -439,7 +439,9 @@ enum_to_oid(24) -> ?secp384r1;
 enum_to_oid(25) -> ?secp521r1;
 enum_to_oid(26) -> ?brainpoolP256r1;
 enum_to_oid(27) -> ?brainpoolP384r1;
-enum_to_oid(28) -> ?brainpoolP512r1.
+enum_to_oid(28) -> ?brainpoolP512r1;
+enum_to_oid(_) ->
+    undefined.
 
 sufficent_ec_support() ->
     CryptoSupport = crypto:supports(),
diff --git a/lib/ssl/test/ssl_handshake_SUITE.erl b/lib/ssl/test/ssl_handshake_SUITE.erl
index 7e8e8d2611..6d020c472b 100644
--- a/lib/ssl/test/ssl_handshake_SUITE.erl
+++ b/lib/ssl/test/ssl_handshake_SUITE.erl
@@ -34,6 +34,7 @@ suite() -> [{ct_hooks,[ts_install_cth]}].
 
 all() -> [decode_hello_handshake,
 	  decode_single_hello_extension_correctly,
+	  decode_supported_elliptic_curves_hello_extension_correctly,
 	  decode_unknown_hello_extension_correctly,
 	  encode_single_hello_sni_extension_correctly].
 
@@ -67,6 +68,17 @@ decode_single_hello_extension_correctly(_Config) ->
     #renegotiation_info{renegotiated_connection = <<0>>}
 	= Extensions#hello_extensions.renegotiation_info.
 
+decode_supported_elliptic_curves_hello_extension_correctly(_Config) ->
+    % List of supported and unsupported curves (RFC4492:S5.1.1)
+    ClientEllipticCurves = [0, tls_v1:oid_to_enum(?sect233k1), 37, tls_v1:oid_to_enum(?sect193r2), 16#badc],
+    % Construct extension binary - modified version of ssl_handshake:encode_hello_extensions([#elliptic_curves{}], _)
+    EllipticCurveList = << <<X:16>> || X <- ClientEllipticCurves>>,
+    ListLen = byte_size(EllipticCurveList),
+    Len = ListLen + 2,
+    Extension = <<?UINT16(?ELLIPTIC_CURVES_EXT), ?UINT16(Len), ?UINT16(ListLen), EllipticCurveList/binary>>,
+    % after decoding we should see only valid curves
+    #hello_extensions{elliptic_curves = DecodedCurves} = ssl_handshake:decode_hello_extensions(Extension),
+    #elliptic_curves{elliptic_curve_list = [?sect233k1, ?sect193r2]} = DecodedCurves.
 
 decode_unknown_hello_extension_correctly(_Config) ->
     FourByteUnknown = <<16#CA,16#FE, ?UINT16(4), 3, 0, 1, 2>>,