From b196730a325cfe74312c3a5f4b1273ba7c705ed6 Mon Sep 17 00:00:00 2001
From: Ingela Anderton Andin <ingela@erlang.org>
Date: Tue, 23 Sep 2014 14:31:52 +0200
Subject: ssl: Servers may include an empty SNI-extension

---
 lib/ssl/src/ssl_handshake.erl        | 3 +++
 lib/ssl/test/ssl_handshake_SUITE.erl | 8 ++++++++
 2 files changed, 11 insertions(+)

diff --git a/lib/ssl/src/ssl_handshake.erl b/lib/ssl/src/ssl_handshake.erl
index 22673e46e2..88ccb94e0b 100644
--- a/lib/ssl/src/ssl_handshake.erl
+++ b/lib/ssl/src/ssl_handshake.erl
@@ -1732,6 +1732,9 @@ dec_hello_extensions(<<?UINT16(?EC_POINT_FORMATS_EXT), ?UINT16(Len),
 							#ec_point_formats{ec_point_format_list =
 									      ECPointFormats}});
 
+dec_hello_extensions(<<?UINT16(?SNI_EXT), ?UINT16(Len), Rest/binary>>, Acc) when Len == 0 ->
+    dec_hello_extensions(Rest, Acc#hello_extensions{sni = ""}); %% Server may send an empy SNI
+
 dec_hello_extensions(<<?UINT16(?SNI_EXT), ?UINT16(Len),
                 ExtData:Len/binary, Rest/binary>>, Acc) ->
     <<?UINT16(_), NameList/binary>> = ExtData,
diff --git a/lib/ssl/test/ssl_handshake_SUITE.erl b/lib/ssl/test/ssl_handshake_SUITE.erl
index e5e942ce1b..8dca733526 100644
--- a/lib/ssl/test/ssl_handshake_SUITE.erl
+++ b/lib/ssl/test/ssl_handshake_SUITE.erl
@@ -39,6 +39,7 @@ all() -> [decode_hello_handshake,
 	  decode_unknown_hello_extension_correctly,
 	  encode_single_hello_sni_extension_correctly,
 	  decode_single_hello_sni_extension_correctly,
+	  decode_empty_server_sni_correctly,
 	  select_proper_tls_1_2_rsa_default_hashsign].
 
 %%--------------------------------------------------------------------
@@ -106,6 +107,13 @@ decode_single_hello_sni_extension_correctly(_Config) ->
     Decoded = ssl_handshake:decode_hello_extensions(SNI),
     Exts = Decoded.
 
+decode_empty_server_sni_correctly(_Config) ->
+    Exts = #hello_extensions{sni = ""},
+    SNI = <<?UINT16(?SNI_EXT),?UINT16(0)>>,
+    Decoded = ssl_handshake:decode_hello_extensions(SNI),
+    Exts = Decoded.
+
+
 select_proper_tls_1_2_rsa_default_hashsign(_Config) ->
     % RFC 5246 section 7.4.1.4.1 tells to use {sha1,rsa} as default signature_algorithm for RSA key exchanges
     {sha, rsa} = ssl_handshake:select_hashsign_algs(undefined, ?rsaEncryption, {3,3}),
-- 
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