ssl: split overloaded function

splits the overloaded function `tls_record:protocol_version` (and its
equivalent in module `dtls`), which was accepting atoms (e.g., tlsv1.2)
and the internal representation of (D)TLS versions (tuples ,e.g., {3,4}
for TLS 1.3) into two different functions. `protocol_version_name`
accepts names (atoms) and returns its internal representation;
`procotol_version` accepts the internal representation and returns its name.

8 files changed, 64 insertions, 49 deletions

diff --git a/lib/ssl/src/dtls_gen_connection.erl b/lib/ssl/src/dtls_gen_connection.erl
index 21a62475e5..446a065ac3 100644
--- a/lib/ssl/src/dtls_gen_connection.erl
+++ b/lib/ssl/src/dtls_gen_connection.erl
@@ -633,7 +633,7 @@ next_dtls_record(Data, StateName, #state{protocol_buffers = #protocol_buffers{
                                          ssl_options = SslOpts} = State0) ->
     case dtls_record:get_dtls_records(Data,
                                       {DataTag, StateName, Version, 
-                                       [dtls_record:protocol_version(Vsn) || Vsn <- ?ALL_AVAILABLE_DATAGRAM_VERSIONS]}, 
+                                       [dtls_record:protocol_version_name(Vsn) || Vsn <- ?ALL_AVAILABLE_DATAGRAM_VERSIONS]},
                                       Buf0, SslOpts) of
 	{Records, Buf1} ->
 	    CT1 = CT0 ++ Records,
diff --git a/lib/ssl/src/dtls_record.erl b/lib/ssl/src/dtls_record.erl
index 0278c34b7c..c0030fe1dc 100644
--- a/lib/ssl/src/dtls_record.erl
+++ b/lib/ssl/src/dtls_record.erl
@@ -43,7 +43,7 @@
 -export([decode_cipher_text/2]).
 
 %% Protocol version handling
--export([protocol_version/1, lowest_protocol_version/1, lowest_protocol_version/2,
+-export([protocol_version/1, protocol_version_name/1, lowest_protocol_version/1, lowest_protocol_version/2,
 	 highest_protocol_version/1, highest_protocol_version/2,
 	 is_higher/2, supported_protocol_versions/0,
 	 is_acceptable_version/2, hello_version/2]).
@@ -263,17 +263,27 @@ decode_cipher_text(#ssl_tls{epoch = Epoch} = CipherText, ConnnectionStates0) ->
 %% Protocol version handling
 %%====================================================================
 
+
 %%--------------------------------------------------------------------
--spec protocol_version(dtls_atom_version() | ssl_record:ssl_version()) ->
-			      ssl_record:ssl_version() | dtls_atom_version().
+-spec protocol_version_name(dtls_atom_version()) -> ssl_record:ssl_version().
 %%
 %% Description: Creates a protocol version record from a version atom
 %% or vice versa.
 %%--------------------------------------------------------------------
-protocol_version('dtlsv1.2') ->
+
+protocol_version_name('dtlsv1.2') ->
     ?DTLS_1_2;
-protocol_version(dtlsv1) ->
-    ?DTLS_1_0;
+protocol_version_name(dtlsv1) ->
+    ?DTLS_1_0.
+
+%%--------------------------------------------------------------------
+-spec protocol_version(ssl_record:ssl_version()) -> dtls_atom_version().
+
+%%
+%% Description: Creates a protocol version record from a version atom
+%% or vice versa.
+%%--------------------------------------------------------------------
+
 protocol_version(?DTLS_1_2) ->
     'dtlsv1.2';
 protocol_version(?DTLS_1_0) ->
@@ -337,7 +347,7 @@ is_higher(_, _) ->
 %%--------------------------------------------------------------------
 supported_protocol_versions() ->
     Fun = fun(Version) ->
-		  protocol_version(Version)
+		  protocol_version_name(Version)
 	  end,
     case application:get_env(ssl, dtls_protocol_version) of
 	undefined ->
diff --git a/lib/ssl/src/ssl.erl b/lib/ssl/src/ssl.erl
index 817ea683bd..60c32f684c 100644
--- a/lib/ssl/src/ssl.erl
+++ b/lib/ssl/src/ssl.erl
@@ -1010,7 +1010,7 @@ negotiated_protocol(#sslsocket{pid = [Pid|_]}) when is_pid(Pid) ->
 %%--------------------------------------------------------------------
 -spec cipher_suites(Description, Version) -> ciphers() when
       Description :: default | all | exclusive | anonymous | exclusive_anonymous,
-      Version :: protocol_version().
+      Version :: protocol_version() | ssl_record:ssl_version().
 
 %% Description: Returns all default and all supported cipher suites for a
 %% TLS/DTLS version
@@ -1019,17 +1019,17 @@ cipher_suites(Description, Version) when Version == 'tlsv1.3';
                                   Version == 'tlsv1.2';
                                   Version == 'tlsv1.1';
                                   Version == tlsv1 ->
-    cipher_suites(Description, tls_record:protocol_version(Version));
+    cipher_suites(Description, tls_record:protocol_version_name(Version));
 cipher_suites(Description, Version)  when Version == 'dtlsv1.2';
                                    Version == 'dtlsv1'->
-    cipher_suites(Description, dtls_record:protocol_version(Version));
+    cipher_suites(Description, dtls_record:protocol_version_name(Version));
 cipher_suites(Description, Version) ->
     [ssl_cipher_format:suite_bin_to_map(Suite) || Suite <- supported_suites(Description, Version)].
 
 %%--------------------------------------------------------------------
 -spec cipher_suites(Description, Version, rfc | openssl) -> [string()] when
       Description :: default | all | exclusive | anonymous,
-      Version :: protocol_version().
+      Version :: protocol_version() | ssl_record:ssl_version().
 
 %% Description: Returns all default and all supported cipher suites for a
 %% TLS/DTLS version
@@ -1038,10 +1038,10 @@ cipher_suites(Description, Version, StringType) when  Version == 'tlsv1.3';
                                                Version == 'tlsv1.2';
                                                Version == 'tlsv1.1';
                                                Version == tlsv1 ->
-    cipher_suites(Description, tls_record:protocol_version(Version), StringType);
+    cipher_suites(Description, tls_record:protocol_version_name(Version), StringType);
 cipher_suites(Description, Version, StringType)  when Version == 'dtlsv1.2';
                                                Version == 'dtlsv1'->
-    cipher_suites(Description, dtls_record:protocol_version(Version), StringType);
+    cipher_suites(Description, dtls_record:protocol_version_name(Version), StringType);
 cipher_suites(Description, Version, rfc) ->
     [ssl_cipher_format:suite_map_to_str(ssl_cipher_format:suite_bin_to_map(Suite))
      || Suite <- supported_suites(Description, Version)];
@@ -1337,8 +1337,8 @@ versions() ->
     SupportedTLSVsns = [tls_record:protocol_version(Vsn) || Vsn <- ConfTLSVsns,  TLSCryptoSupported(Vsn)],
     SupportedDTLSVsns = [dtls_record:protocol_version(Vsn) || Vsn <- ConfDTLSVsns, DTLSCryptoSupported(Vsn)],
 
-    AvailableTLSVsns = [Vsn || Vsn <- ImplementedTLSVsns, TLSCryptoSupported(tls_record:protocol_version(Vsn))],
-    AvailableDTLSVsns = [Vsn || Vsn <- ImplementedDTLSVsns, DTLSCryptoSupported(dtls_record:protocol_version(Vsn))],
+    AvailableTLSVsns = [Vsn || Vsn <- ImplementedTLSVsns, TLSCryptoSupported(tls_record:protocol_version_name(Vsn))],
+    AvailableDTLSVsns = [Vsn || Vsn <- ImplementedDTLSVsns, DTLSCryptoSupported(dtls_record:protocol_version_name(Vsn))],
                                     
     [{ssl_app, ?VSN}, 
      {supported, SupportedTLSVsns}, 
@@ -1672,7 +1672,7 @@ validate_versions(tls, Vsns0) ->
     Validate =
         fun(Version) ->
                 try tls_record:sufficient_crypto_support(Version) of
-                    true -> tls_record:protocol_version(Version);
+                    true -> tls_record:protocol_version_name(Version);
                     false -> option_error(insufficient_crypto_support,
                                           {Version, {versions, Vsns0}})
                 catch error:function_clause ->
@@ -1688,8 +1688,8 @@ validate_versions(dtls, Vsns0) ->
         fun(Version) ->
                 try tls_record:sufficient_crypto_support(
                       dtls_v1:corresponding_tls_version(
-                        dtls_record:protocol_version(Version))) of
-                    true -> dtls_record:protocol_version(Version);
+                        dtls_record:protocol_version_name(Version))) of
+                    true -> dtls_record:protocol_version_name(Version);
                     false-> option_error(insufficient_crypto_support,
                                          {Version, {versions, Vsns0}})
                 catch error:function_clause ->
diff --git a/lib/ssl/src/ssl_handshake.erl b/lib/ssl/src/ssl_handshake.erl
index 6314ed7a66..fb30372999 100644
--- a/lib/ssl/src/ssl_handshake.erl
+++ b/lib/ssl/src/ssl_handshake.erl
@@ -23,6 +23,7 @@
 %%----------------------------------------------------------------------
 
 -module(ssl_handshake).
+-feature(maybe_expr,enable).
 
 -include("ssl_handshake.hrl").
 -include("ssl_record.hrl").
@@ -1004,8 +1005,7 @@ available_suites(ServerCert, UserSuites, Version, undefined, Curve) ->
     filter_unavailable_ecc_suites(Curve, Suites);
 available_suites(ServerCert, UserSuites, Version, HashSigns, Curve) ->
     Suites = available_suites(ServerCert, UserSuites, Version, undefined, Curve),
-    filter_hashsigns(Suites, [ssl_cipher_format:suite_bin_to_map(Suite) || Suite <- Suites], HashSigns, 
-                     Version).
+    filter_hashsigns(Suites, [ssl_cipher_format:suite_bin_to_map(Suite) || Suite <- Suites], HashSigns, Version).
 
 available_signature_algs(undefined, _)  ->
     undefined;
@@ -3320,15 +3320,13 @@ filter_hashsigns(Suites, Algos, HashSigns, Version) ->
     %% HashSigns, and Version never change
     ZipperF = fun (Suite, #{key_exchange := KeyExchange}) -> {Suite, KeyExchange} end,
     SuiteAlgoPairs = lists:zipwith(ZipperF, Suites, Algos),
-    FilterHashSign = fun ({Suite, Kex}) -> filter_hashsigns0(Suite, Kex, HashSigns, Version) end,
+    FilterHashSign = fun ({Suite, Kex}) ->
+                             maybe true ?= filter_hashsigns_helper(Kex, HashSigns, Version),
+                                   {true, Suite}
+                             end
+                     end,
     lists:filtermap(FilterHashSign, SuiteAlgoPairs).
 
-filter_hashsigns0(Suite, KeyExchange, HashSigns, Version) ->
-    case filter_hashsigns_helper(KeyExchange, HashSigns, Version) of
-        true -> {true, Suite};
-        false -> false
-    end.
-
 filter_hashsigns_helper(KeyExchange, HashSigns, _Version)
   when KeyExchange == dhe_ecdsa;
        KeyExchange == ecdhe_ecdsa ->
diff --git a/lib/ssl/src/tls_gen_connection.erl b/lib/ssl/src/tls_gen_connection.erl
index 48e3e00ac1..76e7bc334e 100644
--- a/lib/ssl/src/tls_gen_connection.erl
+++ b/lib/ssl/src/tls_gen_connection.erl
@@ -639,7 +639,7 @@ next_tls_record(Data, StateName,
                 %% This does not allow SSL-3.0 connections, that we do not support
                 %% or interfere with TLS-1.3 extensions to handle version negotiation.
                 AllHelloVersions = [ 'sslv3' | ?ALL_AVAILABLE_VERSIONS],
-                [tls_record:protocol_version(Vsn) || Vsn <- AllHelloVersions];
+                [tls_record:protocol_version_name(Vsn) || Vsn <- AllHelloVersions];
             _ ->
                 State0#state.connection_env#connection_env.negotiated_version
         end,
diff --git a/lib/ssl/src/tls_record.erl b/lib/ssl/src/tls_record.erl
index aa8babf374..92205d22fd 100644
--- a/lib/ssl/src/tls_record.erl
+++ b/lib/ssl/src/tls_record.erl
@@ -49,7 +49,7 @@
 -export([build_tls_record/1]).
 
 %% Protocol version handling
--export([protocol_version/1,  lowest_protocol_version/1, lowest_protocol_version/2,
+-export([protocol_version/1, protocol_version_name/1,  lowest_protocol_version/1, lowest_protocol_version/2,
 	 highest_protocol_version/1, highest_protocol_version/2,
 	 is_higher/2, supported_protocol_versions/0, sufficient_crypto_support/1,
 	 is_acceptable_version/1, is_acceptable_version/2, hello_version/1]).
@@ -273,24 +273,31 @@ decode_cipher_text(_, #ssl_tls{version = Version,
 %%====================================================================
 
 %%--------------------------------------------------------------------
--spec protocol_version(tls_atom_version() | tls_version()) -> 
-			      tls_version() | tls_atom_version().		      
+-spec protocol_version_name(tls_atom_version()) -> tls_version().
 %%     
 %% Description: Creates a protocol version record from a version atom
 %% or vice versa.
 %%--------------------------------------------------------------------
-protocol_version('tlsv1.3') ->
+protocol_version_name('tlsv1.3') ->
     ?TLS_1_3;
-protocol_version('tlsv1.2') ->
+protocol_version_name('tlsv1.2') ->
     ?TLS_1_2;
-protocol_version('tlsv1.1') ->
+protocol_version_name('tlsv1.1') ->
     ?TLS_1_1;
-protocol_version(tlsv1) ->
+protocol_version_name(tlsv1) ->
     ?TLS_1_0;
-protocol_version(sslv3) ->
+protocol_version_name(sslv3) ->
     ?SSL_3_0;
-protocol_version(sslv2) -> %% Backwards compatibility
-    ?SSL_2_0;
+protocol_version_name(sslv2) -> %% Backwards compatibility
+    ?SSL_2_0.
+
+%%--------------------------------------------------------------------
+-spec protocol_version(tls_version()) -> tls_atom_version().
+%%
+%% Description: Creates a protocol version record from a version atom
+%% or vice versa.
+%%--------------------------------------------------------------------
+
 protocol_version(?TLS_1_3) ->
     'tlsv1.3';
 protocol_version(?TLS_1_2) ->
@@ -359,7 +366,7 @@ is_higher(_, _) ->
 %%--------------------------------------------------------------------
 supported_protocol_versions() ->
     Fun = fun(Version) ->
-		  protocol_version(Version) 
+		  protocol_version_name(Version)
 	  end,
     case application:get_env(ssl, protocol_version) of
 	undefined ->
diff --git a/lib/ssl/test/ssl_cert_tests.erl b/lib/ssl/test/ssl_cert_tests.erl
index 8df08398da..a551025ea5 100644
--- a/lib/ssl/test/ssl_cert_tests.erl
+++ b/lib/ssl/test/ssl_cert_tests.erl
@@ -467,7 +467,7 @@ test_ciphers(_, 'tlsv1.3' = Version) ->
                  end, Ciphers);
 test_ciphers(_, Version) when Version == 'dtlsv1';
                                 Version == 'dtlsv1.2' ->
-    NVersion = dtls_record:protocol_version(Version),
+    NVersion = dtls_record:protocol_version_name(Version),
     Ciphers = [ssl_cipher_format:suite_bin_to_map(Bin) ||  Bin <- dtls_v1:suites(NVersion)],
     ct:log("Version ~p Testing  ~p~n", [Version, Ciphers]),
     OpenSSLCiphers = openssl_ciphers(),
diff --git a/lib/ssl/test/ssl_test_lib.erl b/lib/ssl/test/ssl_test_lib.erl
index db4bd32741..f3fb5c4f7b 100644
--- a/lib/ssl/test/ssl_test_lib.erl
+++ b/lib/ssl/test/ssl_test_lib.erl
@@ -2836,7 +2836,7 @@ openssl_tls_version_support(Version, Config0) ->
         true ->
             openssl_tls_version_support(tls, TLSOpts, Port, Exe, TLSArgs);
         false ->
-            DTLSTupleVersion = dtls_record:protocol_version(Version),
+            DTLSTupleVersion = dtls_record:protocol_version_name(Version),
             CorrespondingTLSVersion = dtls_v1:corresponding_tls_version(DTLSTupleVersion),
             AtomTLSVersion = tls_record:protocol_version(CorrespondingTLSVersion),
             CorrTLSOpts = [{protocol,tls}, {versions, [AtomTLSVersion]},
@@ -3660,8 +3660,8 @@ protocol_version(Config, atom) ->
     case proplists:get_value(protocol, Config) of
 	dtls ->
 	   dtls_record:protocol_version(protocol_version(Config, tuple));
-	_ ->							 
-           tls_record:protocol_version(protocol_version(Config, tuple))	
+	_ ->
+            tls_record:protocol_version(protocol_version(Config, tuple))
    end.
 
 protocol_options(Config, Options) ->
@@ -3715,11 +3715,11 @@ clean_start(keep_version) ->
 
 
 tls_version('dtlsv1' = Atom) ->
-    dtls_v1:corresponding_tls_version(dtls_record:protocol_version(Atom));
+    dtls_v1:corresponding_tls_version(dtls_record:protocol_version_name(Atom));
 tls_version('dtlsv1.2' = Atom) ->
-    dtls_v1:corresponding_tls_version(dtls_record:protocol_version(Atom));
+    dtls_v1:corresponding_tls_version(dtls_record:protocol_version_name(Atom));
 tls_version(Atom) ->
-    tls_record:protocol_version(Atom).
+    tls_record:protocol_version_name(Atom).
 
 
 n_version(Version) when
@@ -3728,10 +3728,10 @@ n_version(Version) when
       Version == 'tlsv1.1';
       Version == 'tlsv1';
       Version == 'sslv3' ->
-    tls_record:protocol_version(Version);
+    tls_record:protocol_version_name(Version);
 n_version(Version) when Version == 'dtlsv1.2';
                         Version == 'dtlsv1' ->
-    dtls_record:protocol_version(Version).
+    dtls_record:protocol_version_name(Version).
 
 consume_port_exit(OpenSSLPort) ->
     receive