Use ASN1DER for TxID hashing instead of Protobuf

It is not guaranteed that Protobuf encoding will always generate the
same bytes for the same structure. This could lead to different hashes
for the same object that's why we should use ASN1 DER (which will surely
generate the same bytes).


Change-Id: I75420e8436fb8144490e3801c51886062a0bd2a4
Signed-off-by: Gabor Hosszu <gabor@digitalasset.com>

bddtests/peer_basic.feature

@@ -349,8 +349,6 @@ Feature: Network of Peers
 
 #    @doNotDecompose
 #    @wip
-#    sha256 = '53a54f606b9cc14ae2825cc50736b183cf8d6fd0131b9d3176997efcf77d775f'
-#             calculated using all the args
 	Scenario: chaincode map single peer content generated ID
 	    Given we compose "docker-compose-1.yml"
 	    When requesting "/chain" from "vp0"
@@ -366,7 +364,7 @@ Feature: Network of Peers
             |   a   | 10 |
 	    Then I should have received a transactionID
 	    Then I wait up to "25" seconds for transaction to be committed to all peers
-	    Then I check the transaction ID if it is "a97267efe0391a5c0be28f79e8cb7f841aca1b952f028ec796b61c92aef6936c"
+	    Then I check the transaction ID if it is "73b88d92d86502eb66288f84fafae848fed0d21790f2ef1475850f4b635c47f0"
 
     Scenario: chaincode example 01 single peer rejection message
 	    Given we compose "docker-compose-1-exp.yml"

core/devops.go

@@ -215,7 +215,7 @@ func (d *Devops) invokeOrQuery(ctx context.Context, chaincodeInvocationSpec *pb.
 	var generr error
 	if invoke {
 		if customIDgenAlg != "" {
-			ctorbytes, merr := proto.Marshal(chaincodeInvocationSpec.ChaincodeSpec.CtorMsg)
+			ctorbytes, merr := asn1.Marshal(*chaincodeInvocationSpec.ChaincodeSpec.CtorMsg)
 			if merr != nil {
 				return nil, fmt.Errorf("Error marshalling constructor: %s", merr)
 			}
@@ -456,7 +456,7 @@ func (d *Devops) EXP_ExecuteWithBinding(ctx context.Context, executeWithBinding
 			return &pb.Response{Status: pb.Response_FAILURE, Msg: []byte(err.Error())}, nil
 		}
 
-		ctorbytes, merr := proto.Marshal(executeWithBinding.ChaincodeInvocationSpec.ChaincodeSpec.CtorMsg)
+		ctorbytes, merr := asn1.Marshal(*executeWithBinding.ChaincodeInvocationSpec.ChaincodeSpec.CtorMsg)
 		if merr != nil {
 			return nil, fmt.Errorf("Error marshalling constructor: %s", err)
 		}