From db65ed04d9ac203d3cbf3ab248971a3ea73bcc81 Mon Sep 17 00:00:00 2001
From: Anna Shaleva <shaleva.ann@nspcc.ru>
Date: Mon, 3 Aug 2020 19:27:32 +0300
Subject: [PATCH] consensus: apply policy during verifyBlock

To follow C# implementation we should also check proposed block on
policy matching.
---
 pkg/consensus/consensus.go            | 20 ++++++++++++++++++++
 pkg/core/blockchain.go                | 10 ++++++++++
 pkg/core/blockchainer/blockchainer.go |  2 ++
 pkg/network/helper_test.go            |  8 ++++++++
 4 files changed, 40 insertions(+)

diff --git a/pkg/consensus/consensus.go b/pkg/consensus/consensus.go
index 921da8659..d41373af4 100644
--- a/pkg/consensus/consensus.go
+++ b/pkg/consensus/consensus.go
@@ -341,7 +341,19 @@ func (s *service) getTx(h util.Uint256) block.Transaction {
 
 func (s *service) verifyBlock(b block.Block) bool {
 	coreb := &b.(*neoBlock).Block
+
+	maxBlockSize := int(s.Chain.GetMaxBlockSize())
+	size := io.GetVarSize(coreb)
+	if size > maxBlockSize {
+		s.log.Warn("proposed block size exceeds policy max block size",
+			zap.Int("max size allowed", maxBlockSize),
+			zap.Int("block size", size))
+		return false
+	}
+
+	var fee int64
 	for _, tx := range coreb.Transactions {
+		fee += tx.SystemFee
 		if err := s.Chain.VerifyTx(tx, coreb); err != nil {
 			s.log.Warn("invalid transaction in proposed block",
 				zap.Stringer("hash", tx.Hash()),
@@ -350,6 +362,14 @@ func (s *service) verifyBlock(b block.Block) bool {
 		}
 	}
 
+	maxBlockSysFee := s.Chain.GetMaxBlockSystemFee()
+	if fee > maxBlockSysFee {
+		s.log.Warn("proposed block system fee exceeds policy max block system fee",
+			zap.Int("max system fee allowed", int(maxBlockSysFee)),
+			zap.Int("block system fee", int(fee)))
+		return false
+	}
+
 	return true
 }
 
diff --git a/pkg/core/blockchain.go b/pkg/core/blockchain.go
index eb80d4ee9..8b571e8a5 100644
--- a/pkg/core/blockchain.go
+++ b/pkg/core/blockchain.go
@@ -1147,6 +1147,16 @@ func (bc *Blockchain) FeePerByte() int64 {
 	return bc.contracts.Policy.GetFeePerByteInternal(bc.dao)
 }
 
+// GetMaxBlockSize returns maximum allowed block size from native Policy contract.
+func (bc *Blockchain) GetMaxBlockSize() uint32 {
+	return bc.contracts.Policy.GetMaxBlockSizeInternal(bc.dao)
+}
+
+// GetMaxBlockSystemFee returns maximum block system fee from native Policy contract.
+func (bc *Blockchain) GetMaxBlockSystemFee() int64 {
+	return bc.contracts.Policy.GetMaxBlockSystemFeeInternal(bc.dao)
+}
+
 // GetMemPool returns the memory pool of the blockchain.
 func (bc *Blockchain) GetMemPool() *mempool.Pool {
 	return &bc.memPool
diff --git a/pkg/core/blockchainer/blockchainer.go b/pkg/core/blockchainer/blockchainer.go
index fc9ca0110..b1ff94f12 100644
--- a/pkg/core/blockchainer/blockchainer.go
+++ b/pkg/core/blockchainer/blockchainer.go
@@ -50,6 +50,8 @@ type Blockchainer interface {
 	GetTestVM(tx *transaction.Transaction) *vm.VM
 	GetTransaction(util.Uint256) (*transaction.Transaction, uint32, error)
 	mempool.Feer // fee interface
+	GetMaxBlockSize() uint32
+	GetMaxBlockSystemFee() int64
 	PoolTx(*transaction.Transaction) error
 	SubscribeForBlocks(ch chan<- *block.Block)
 	SubscribeForExecutions(ch chan<- *state.AppExecResult)
diff --git a/pkg/network/helper_test.go b/pkg/network/helper_test.go
index 2e7d336e6..45ccc3615 100644
--- a/pkg/network/helper_test.go
+++ b/pkg/network/helper_test.go
@@ -40,6 +40,14 @@ func (chain testChain) FeePerByte() int64 {
 	panic("TODO")
 }
 
+func (chain testChain) GetMaxBlockSystemFee() int64 {
+	panic("TODO")
+}
+
+func (chain testChain) GetMaxBlockSize() uint32 {
+	panic("TODO")
+}
+
 func (chain testChain) AddHeaders(...*block.Header) error {
 	panic("TODO")
 }