Remove verification for createNewBlock

The value returned must be assumed untrusted because the service
is lacking the context to verify it belongs to the chain.
Verifications must be done upstream.

byzcoin/service.go

@@ -34,9 +34,6 @@ import (
 	uuid "gopkg.in/satori/go.uuid.v1"
 )
 
-// for testing purpose until we have proper interfaces
-var testCorruptSSBReply *skipchain.StoreSkipBlockReply
-
 var pairingSuite = suites.MustFind("bn256.adapter").(*pairing.SuiteBn256)
 
 // This is to boost the acceptable timestamp window when dealing with
@@ -890,24 +887,14 @@ func (s *Service) createNewBlock(scID skipchain.SkipBlockID, r *onet.Roster, tx
 			return nil, err
 		}
 
-		if testCorruptSSBReply != nil {
-			ssbReply = testCorruptSSBReply
-		}
-
 		if ssbReply.Latest == nil {
 			return nil, errors.New("got an empty reply")
 		}
 
-		// simple integrity check because the block will be used to cache
-		// the state changes
-		if !ssbReply.Latest.CalculateHash().Equal(ssbReply.Latest.Hash) {
-			return nil, errors.New("block in reply is corrupted")
-		}
-
-		// and check that we got the expected block
-		if ssbReply.Latest.Index != sb.Index {
-			return nil, errors.New("got a different block")
-		}
+		// we're not doing more verification because the block should not be used
+		// as is. It's up to the client to fetch the forward link of the previous
+		// block to insure the new one has been validated but at this moment we
+		// can't do it because it might not be propagated to this node yet
 	}
 	if err != nil {
 		return nil, err

byzcoin/service_test.go

@@ -81,25 +81,7 @@ func TestService_CreateGenesisBlock(t *testing.T) {
 	genesisMsg.BlockInterval = 100 * time.Millisecond
 	genesisMsg.MaxBlockSize = 1 * 1e6
 
-	// corrupted reply
-	testCorruptSSBReply = &skipchain.StoreSkipBlockReply{}
-	_, err = service.CreateGenesisBlock(genesisMsg)
-	require.Error(t, err)
-	require.Equal(t, "got an empty reply", err.Error())
-
-	testCorruptSSBReply.Latest = skipchain.NewSkipBlock()
-	_, err = service.CreateGenesisBlock(genesisMsg)
-	require.Error(t, err)
-	require.Equal(t, "block in reply is corrupted", err.Error())
-
-	testCorruptSSBReply.Latest.Index = 1
-	testCorruptSSBReply.Latest.Hash = testCorruptSSBReply.Latest.CalculateHash()
-	_, err = service.CreateGenesisBlock(genesisMsg)
-	require.Error(t, err)
-	require.Equal(t, "got a different block", err.Error())
-
 	// finally passing
-	testCorruptSSBReply = nil
 	resp, err = service.CreateGenesisBlock(genesisMsg)
 	require.Nil(t, err)
 	assert.Equal(t, CurrentVersion, resp.Version)