From 4e0a2c8e8cf418528742500dff8e6916e4fd1bc5 Mon Sep 17 00:00:00 2001
From: Gustav Simonsson <gustav.simonsson@gmail.com>
Date: Wed, 22 Apr 2015 15:29:19 +0200
Subject: [PATCH] Validate block header UncleHash against calculated hash

---
 core/block_processor.go | 11 +++++++++--
 core/types/block.go     |  4 ++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/core/block_processor.go b/core/block_processor.go
index 28636a725..f33f0d433 100644
--- a/core/block_processor.go
+++ b/core/block_processor.go
@@ -219,14 +219,21 @@ func (sm *BlockProcessor) processWithParent(block, parent *types.Block) (logs st
 	// can be used by light clients to make sure they've received the correct Txs
 	txSha := types.DeriveSha(block.Transactions())
 	if txSha != header.TxHash {
-		err = fmt.Errorf("validating transaction root. received=%x got=%x", header.TxHash, txSha)
+		err = fmt.Errorf("invalid transaction root hash. received=%x calculated=%x", header.TxHash, txSha)
 		return
 	}
 
 	// Tre receipt Trie's root (R = (Tr [[H1, R1], ... [Hn, R1]]))
 	receiptSha := types.DeriveSha(receipts)
 	if receiptSha != header.ReceiptHash {
-		err = fmt.Errorf("validating receipt root. received=%x got=%x", header.ReceiptHash, receiptSha)
+		err = fmt.Errorf("invalid receipt root hash. received=%x calculated=%x", header.ReceiptHash, receiptSha)
+		return
+	}
+
+	// Verify UncleHash before running other uncle validations
+	unclesSha := block.CalculateUnclesHash()
+	if unclesSha != header.UncleHash {
+		err = fmt.Errorf("invalid uncles root hash. received=%x calculated=%x", header.UncleHash, unclesSha)
 		return
 	}
 
diff --git a/core/types/block.go b/core/types/block.go
index f9206ec76..fa83fc8e8 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -209,6 +209,10 @@ func (self *Block) Uncles() []*Header {
 	return self.uncles
 }
 
+func (self *Block) CalculateUnclesHash() common.Hash {
+	return rlpHash(self.uncles)
+}
+
 func (self *Block) SetUncles(uncleHeaders []*Header) {
 	self.uncles = uncleHeaders
 	self.header.UncleHash = rlpHash(uncleHeaders)