Add a test for correct handling of the cryptopro bug extension

This was complicated by the fact that we were using this extension for our
duplicate extension handling tests. In order to add tests for cryptopro
bug the duplicate extension handling tests needed to change first.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7984)

test/recipes/70-test_sslextension.t

@@ -88,9 +88,11 @@ sub inject_duplicate_extension
     foreach my $message (@{$proxy->message_list}) {
         if ($message->mt == $message_type) {
           my %extensions = %{$message->extension_data};
-            # Add a duplicate (unknown) extension.
-            $message->set_extension(TLSProxy::Message::EXT_DUPLICATE_EXTENSION, "");
-            $message->set_extension(TLSProxy::Message::EXT_DUPLICATE_EXTENSION, "");
+            # Add a duplicate extension. We use cryptopro_bug since we never
+            # normally write that one, and it is allowed as unsolicited in the
+            # ServerHello
+            $message->set_extension(TLSProxy::Message::EXT_CRYPTOPRO_BUG_EXTENSION, "");
+            $message->dupext(TLSProxy::Message::EXT_CRYPTOPRO_BUG_EXTENSION);
             $message->repack();
         }
     }
@@ -173,9 +175,23 @@ sub inject_unsolicited_extension
     $sent_unsolisited_extension = 1;
 }
 
+sub inject_cryptopro_extension
+{
+    my $proxy = shift;
+
+    # We're only interested in the initial ClientHello
+    if ($proxy->flight != 0) {
+        return;
+    }
+
+    my $message = ${$proxy->message_list}[0];
+    $message->set_extension(TLSProxy::Message::EXT_CRYPTOPRO_BUG_EXTENSION, "");
+    $message->repack();
+}
+
 # Test 1-2: Sending a duplicate extension should fail.
 $proxy->start() or plan skip_all => "Unable to start up Proxy for tests";
-plan tests => 7;
+plan tests => 8;
 ok($fatal_alert, "Duplicate ClientHello extension");
 
 $fatal_alert = 0;
@@ -234,3 +250,11 @@ SKIP: {
     $proxy->start();
     ok($fatal_alert, "Unsolicited server name extension (TLSv1.3)");
 }
+
+#Test 8: Send the cryptopro extension in a ClientHello. Normally this is an
+#        unsolicited extension only ever seen in the ServerHello. We should
+#        ignore it in a ClientHello
+$proxy->clear();
+$proxy->filter(\&inject_cryptopro_extension);
+$proxy->start();
+ok(TLSProxy::Message->success(), "Cryptopro extension in ClientHello");

util/perl/TLSProxy/Certificate.pm

@@ -138,11 +138,6 @@ sub set_message_contents
             $extensions .= pack("n", $key);
             $extensions .= pack("n", length($extdata));
             $extensions .= $extdata;
-            if ($key == TLSProxy::Message::EXT_DUPLICATE_EXTENSION) {
-              $extensions .= pack("n", $key);
-              $extensions .= pack("n", length($extdata));
-              $extensions .= $extdata;
-            }
         }
         $data = pack('C', length($self->context()));
         $data .= $self->context;

util/perl/TLSProxy/ClientHello.pm

@@ -124,11 +124,6 @@ sub extension_contents
     $extension .= pack("n", $key);
     $extension .= pack("n", length($extdata));
     $extension .= $extdata;
-    if ($key == TLSProxy::Message::EXT_DUPLICATE_EXTENSION) {
-        $extension .= pack("n", $key);
-        $extension .= pack("n", length($extdata));
-        $extension .= $extdata;
-    }
     return $extension;
 }
 
@@ -151,6 +146,8 @@ sub set_message_contents
     foreach my $key (keys %{$self->extension_data}) {
         next if ($key == TLSProxy::Message::EXT_PSK);
         $extensions .= $self->extension_contents($key);
+        #Add extension twice if we are duplicating that extension
+        $extensions .= $self->extension_contents($key) if ($key == $self->dupext);
     }
     #PSK extension always goes last...
     if (defined ${$self->extension_data}{TLSProxy::Message::EXT_PSK}) {

util/perl/TLSProxy/EncryptedExtensions.pm

@@ -81,11 +81,6 @@ sub set_message_contents
         $extensions .= pack("n", $key);
         $extensions .= pack("n", length($extdata));
         $extensions .= $extdata;
-        if ($key == TLSProxy::Message::EXT_DUPLICATE_EXTENSION) {
-            $extensions .= pack("n", $key);
-            $extensions .= pack("n", length($extdata));
-            $extensions .= $extdata;
-        }
     }
 
     $data = pack('n', length($extensions));

util/perl/TLSProxy/Message.pm

@@ -86,10 +86,7 @@ use constant {
     EXT_SIG_ALGS_CERT => 50,
     EXT_RENEGOTIATE => 65281,
     EXT_NPN => 13172,
-    # This extension is an unofficial extension only ever written by OpenSSL
-    # (i.e. not read), and even then only when enabled. We use it to test
-    # handling of duplicate extensions.
-    EXT_DUPLICATE_EXTENSION => 0xfde8,
+    EXT_CRYPTOPRO_BUG_EXTENSION => 0xfde8,
     EXT_UNKNOWN => 0xfffe,
     #Unknown extension that should appear last
     EXT_FORCE_LAST => 0xffff
@@ -420,7 +417,8 @@ sub new
         records => $records,
         mt => $mt,
         startoffset => $startoffset,
-        message_frag_lens => $message_frag_lens
+        message_frag_lens => $message_frag_lens,
+        dupext => -1
     };
 
     return bless $self, $class;
@@ -575,6 +573,14 @@ sub encoded_length
     my $self = shift;
     return TLS_MESSAGE_HEADER_LENGTH + length($self->data);
 }
+sub dupext
+{
+    my $self = shift;
+    if (@_) {
+        $self->{dupext} = shift;
+    }
+    return $self->{dupext};
+}
 sub successondata
 {
     my $class = shift;

util/perl/TLSProxy/ServerHello.pm

@@ -154,7 +154,7 @@ sub set_message_contents
         $extensions .= pack("n", $key);
         $extensions .= pack("n", length($extdata));
         $extensions .= $extdata;
-        if ($key == TLSProxy::Message::EXT_DUPLICATE_EXTENSION) {
+        if ($key == $self->dupext) {
           $extensions .= pack("n", $key);
           $extensions .= pack("n", length($extdata));
           $extensions .= $extdata;