Don't store root cert twice when included in submission.

Closes CATLFISH-96.

1 files changed, 12 insertions, 9 deletions

diff --git a/src/x509.erl b/src/x509.erl
index 4eb9755..0b32c4e 100644
--- a/src/x509.erl
+++ b/src/x509.erl
@@ -25,7 +25,12 @@ normalise_chain(AcceptableRootCerts, CertChain) ->
         {false, Reason} ->
             {error, Reason};
         {true, Root} ->
-            {ok, CertChain ++ Root}
+            case lists:member(Root, CertChain) of
+                true ->
+                    {ok, CertChain};
+                false ->
+                    {ok, CertChain ++ [Root]}
+            end
     end.
 
 -spec cert_string(binary()) -> string().
@@ -70,10 +75,8 @@ detox(LeafDer, ChainDer) ->
 %% argument is: leaf cert in head, chain in tail. Order of certs in first
 %% argument is irrelevant.
 %%
-%% Return {false, Reason} or {true, ListWithRoot}. Note that
-%% ListWithRoot allways contain exactly one element -- a CA cert from
-%% first argument (AcceptableRootCerts) signing the root of the
-%% chain. FIXME: Any point in returning this as a list?
+%% Return {false, Reason} or {true, Root} where Root is a CA cert from
+%% AcceptableRootCerts signing the root of the chain.
 normalise_chain(_, _, MaxChainLength) when MaxChainLength =< 0 ->
     %% Chain too long.
     {false, chain_too_long};
@@ -82,7 +85,7 @@ normalise_chain(AcceptableRootCerts, [TopCert], MaxChainLength) ->
     case lists:member(TopCert, AcceptableRootCerts) of
         true ->
             %% Top cert is part of chain.
-            {true, [TopCert]};
+            {true, TopCert};
         false when MaxChainLength =< 1 ->
             %% Chain too long.
             {false, chain_too_long};
@@ -90,11 +93,11 @@ normalise_chain(AcceptableRootCerts, [TopCert], MaxChainLength) ->
             %% Top cert _might_ be signed by a cert in truststore.
             case signer(TopCert, AcceptableRootCerts) of
                 notfound -> {false, root_unknown};
-                Root -> {true, [Root]}
+                Root -> {true, Root}
             end
     end;
-normalise_chain(AcceptableRootCerts, [BottomCert|Rest], MaxChainLength) ->
-    case signed_by_p(BottomCert, hd(Rest)) of
+normalise_chain(AcceptableRootCerts, [Cert|Rest], MaxChainLength) ->
+    case signed_by_p(Cert, hd(Rest)) of
         true -> normalise_chain(AcceptableRootCerts, Rest, MaxChainLength - 1);
         false -> {false, signature_mismatch}
     end.