Merge pull request #133 from scrtlabs/add-implicit-hash-to-header

remove ImplicitHash from the blockheader hash calculation

Author: cboh4

state/state.go

@@ -280,10 +280,10 @@ func (state State) MakeBlock(
 		panic("Failed to validate generated random")
 	}
 
-	implicitHash, err := tmenclave.GetImplicitHash()
-	if err != nil {
-		panic("Failed to get implicit hash")
-	}
+	// implicitHash, err := tmenclave.GetImplicitHash()
+	// if err != nil {
+	// 	panic("Failed to get implicit hash")
+	// }
 	// ScrtLabs changes out <-
 
 	// Fill rest of header with state data.
@@ -292,7 +292,7 @@ func (state State) MakeBlock(
 		timestamp, state.LastBlockID,
 		state.Validators.Hash(), state.NextValidators.Hash(),
 		state.ConsensusParams.Hash(), state.AppHash, state.LastResultsHash,
-		proposerAddress, &encryptedRandom, implicitHash,
+		proposerAddress, &encryptedRandom, nil,
 	)
 
 	return block

state/validation.go

@@ -121,14 +121,15 @@ func validateBlock(state State, block *types.Block) error {
 		}
 	}
 
-	expectedImplicitHash, err := tmenclave.GetImplicitHash() // hash from last block's scheduling
-	if err != nil {
-		return fmt.Errorf("failed to get implicit hash: %w", err)
-	}
-	if !bytes.Equal(block.Header.ImplicitHash, expectedImplicitHash) {
+	// expectedImplicitHash, err := tmenclave.GetImplicitHash() // hash from last block's scheduling
+	// if err != nil {
+	// 	return fmt.Errorf("failed to get implicit hash: %w", err)
+	// }
+	if len(block.Header.ImplicitHash) > 0 {
 		emptySha256 := sha256.Sum256([]byte{})
-		if !(bytes.Equal(block.Header.ImplicitHash, []byte{}) && bytes.Equal(expectedImplicitHash, emptySha256[:])) {
-			return fmt.Errorf("implicit_hash mismatch: expected %X, got %X", hex.EncodeToString(expectedImplicitHash), hex.EncodeToString(block.Header.ImplicitHash))
+		if !bytes.Equal(block.Header.ImplicitHash, emptySha256[:]) {
+			return fmt.Errorf("implicit_hash mismatch: expected nil or empty hash, got %s",
+				block.Header.ImplicitHash.String())
 		}
 	}
 

types/block.go

@@ -489,7 +489,7 @@ func (h *Header) Hash() cmtbytes.HexBytes {
 		cdcEncode(h.LastResultsHash),
 		cdcEncode(h.EvidenceHash),
 		cdcEncode(h.ProposerAddress),
-		cdcEncode(h.ImplicitHash),
+		// cdcEncode(h.ImplicitHash),
 	})
 }
 
@@ -529,7 +529,7 @@ func (h *Header) StringIndented(indent string) string {
 		indent, h.LastResultsHash,
 		indent, h.EvidenceHash,
 		indent, h.ProposerAddress,
-		indent, h.ImplicitHash,
+		// indent, h.ImplicitHash,
 		indent, h.Hash(),
 	)
 }