Decrease minimum gas price at apricot upgrade

6 files changed, 105 insertions, 21 deletions

diff --git a/coreth.go b/coreth.go
index 25e9da2..c39b171 100644
--- a/coreth.go
+++ b/coreth.go
@@ -3,6 +3,7 @@ package coreth
 import (
 	"crypto/ecdsa"
 	"io"
+	"math/big"
 	"os"
 
 	"github.com/ava-labs/coreth/consensus/dummy"
@@ -213,6 +214,11 @@ func (self *ETHChain) GetTxPool() *core.TxPool {
 	return self.backend.TxPool()
 }
 
+// SetGasPrice sets the gas price on the backend
+func (self *ETHChain) SetGasPrice(newGasPrice *big.Int) {
+	self.backend.SetGasPrice(newGasPrice)
+}
+
 type Key struct {
 	Address    common.Address
 	PrivateKey *ecdsa.PrivateKey
diff --git a/eth/backend.go b/eth/backend.go
index e26cbb3..9b6f1e4 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -559,3 +559,13 @@ func (s *Ethereum) AcceptedBlock() *types.Block {
 	}
 	return s.blockchain.CurrentBlock()
 }
+
+// SetGasPrice sets the minimum gas price to [newGasPrice]
+// sets the price on [s], [txPool], and the gas price oracle
+func (s *Ethereum) SetGasPrice(newGasPrice *big.Int) {
+	s.lock.Lock()
+	s.gasPrice = newGasPrice
+	s.lock.Unlock()
+	s.txPool.SetGasPrice(newGasPrice)
+	s.APIBackend.gpo.SetGasPrice(newGasPrice)
+}
diff --git a/eth/gasprice/gasprice.go b/eth/gasprice/gasprice.go
index 33810b2..dc62ad6 100644
--- a/eth/gasprice/gasprice.go
+++ b/eth/gasprice/gasprice.go
@@ -48,12 +48,12 @@ type OracleBackend interface {
 // Oracle recommends gas prices based on the content of recent
 // blocks. Suitable for both light and full clients.
 type Oracle struct {
-	backend   OracleBackend
-	lastHead  common.Hash
-	lastPrice *big.Int
-	maxPrice  *big.Int
-	cacheLock sync.RWMutex
-	fetchLock sync.Mutex
+	backend     OracleBackend
+	lastHead    common.Hash
+	minGasPrice *big.Int
+	maxPrice    *big.Int
+	cacheLock   sync.RWMutex
+	fetchLock   sync.Mutex
 
 	checkBlocks int
 	percentile  int
@@ -83,7 +83,7 @@ func NewOracle(backend OracleBackend, params Config) *Oracle {
 	}
 	return &Oracle{
 		backend:     backend,
-		lastPrice:   params.Default,
+		minGasPrice: params.Default,
 		maxPrice:    maxPrice,
 		checkBlocks: blocks,
 		percentile:  percent,
@@ -93,7 +93,12 @@ func NewOracle(backend OracleBackend, params Config) *Oracle {
 // SuggestPrice returns a gasprice so that newly created transaction can
 // have a very high chance to be included in the following blocks.
 func (gpo *Oracle) SuggestPrice(ctx context.Context) (*big.Int, error) {
-	return params.MinGasPrice, nil
+	return gpo.minGasPrice, nil
+}
+
+// SetGasPrice sets the minimum gas price to [newGasPrice]
+func (gpo *Oracle) SetGasPrice(newGasPrice *big.Int) {
+	gpo.minGasPrice = newGasPrice
 }
 
 type getBlockPricesResult struct {
diff --git a/params/protocol_params.go b/params/protocol_params.go
index fdfb9a5..fe6e6c2 100644
--- a/params/protocol_params.go
+++ b/params/protocol_params.go
@@ -152,8 +152,42 @@ var (
 	GenesisDifficulty      = big.NewInt(131072) // Difficulty of the Genesis block.
 	MinimumDifficulty      = big.NewInt(131072) // The minimum that the difficulty may ever be.
 	DurationLimit          = big.NewInt(13)     // The decision boundary on the blocktime duration used to determine whether difficulty should go up or not.
+)
 
+// Minimum Gas Price
+var (
 	// MinGasPrice is the number of nAVAX required per gas unit for a transaction
 	// to be valid, measured in wei
-	MinGasPrice = big.NewInt(470 * GWei)
+	MinGasPrice        = big.NewInt(470 * GWei)
+	LaunchMinGasPrice  = big.NewInt(470 * GWei)
+	ApricotMinGasPrice = big.NewInt(100 * GWei)
 )
+
+// GasPrice provides an interface to get the minimum
+// gas price
+type GasPrice interface {
+	GetMin(blockTimestamp *big.Int) *big.Int
+}
+
+// NewGasPrice returns a getter for the GasPrice based on a block timestamp
+func NewGasPrice(apricotTimestamp *big.Int) GasPrice {
+	return &minGasPriceFetcher{
+		launchPrice:      LaunchMinGasPrice,
+		apricotPrice:     ApricotMinGasPrice,
+		apricotTimestamp: apricotTimestamp,
+	}
+}
+
+type minGasPriceFetcher struct {
+	apricotTimestamp          *big.Int
+	launchPrice, apricotPrice *big.Int
+}
+
+// GetMin returns the minimum gas price for a block with the given timestamp
+func (m *minGasPriceFetcher) GetMin(blockTimestamp *big.Int) *big.Int {
+	if m.apricotTimestamp == nil || blockTimestamp.Cmp(m.apricotTimestamp) >= 0 {
+		return m.apricotPrice
+	}
+
+	return m.launchPrice
+}
diff --git a/plugin/evm/block.go b/plugin/evm/block.go
index 5a0d377..08ef231 100644
--- a/plugin/evm/block.go
+++ b/plugin/evm/block.go
@@ -6,9 +6,9 @@ package evm
 import (
 	"errors"
 	"fmt"
+	"math/big"
 
 	"github.com/ava-labs/coreth/core/types"
-	"github.com/ava-labs/coreth/params"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/rlp"
 
@@ -85,9 +85,11 @@ func (b *Block) Verify() error {
 	// Only enforce a minimum fee when bootstrapping has finished
 	if b.vm.ctx.IsBootstrapped() {
 		// Ensure the minimum gas price is paid for every transaction
+		timestamp := b.ethBlock.Header().Time
+		minGasPrice := b.vm.minGasPrice.GetMin(new(big.Int).SetUint64(timestamp))
 		for _, tx := range b.ethBlock.Transactions() {
-			if tx.GasPrice().Cmp(params.MinGasPrice) < 0 {
-				return errInvalidBlock
+			if tx.GasPrice().Cmp(minGasPrice) < 0 {
+				return fmt.Errorf("block contains tx %s with gas price too low (%d < %d), timestamp: %d", tx.Hash(), tx.GasPrice(), minGasPrice, timestamp)
 			}
 		}
 	}
@@ -139,17 +141,21 @@ func (b *Block) Verify() error {
 		}
 
 		utx := tx.UnsignedTx.(UnsignedAtomicTx)
-		if utx.SemanticVerify(vm, tx) != nil {
-			return errInvalidBlock
+		if err := utx.SemanticVerify(vm, tx); err != nil {
+			return fmt.Errorf("block atomic tx failed verification due to: %w", err)
 		}
 		bc := vm.chain.BlockChain()
 		_, _, _, err = bc.Processor().Process(b.ethBlock, pState, *bc.GetVMConfig())
 		if err != nil {
-			return errInvalidBlock
+			return fmt.Errorf("block failed processing due to: %w", err)
 		}
 	}
 	_, err := b.vm.chain.InsertChain([]*types.Block{b.ethBlock})
-	return err
+	if err != nil {
+		return fmt.Errorf("failed to insert block into chain due to: %w", err)
+	}
+
+	return nil
 }
 
 // Bytes implements the snowman.Block interface
diff --git a/plugin/evm/vm.go b/plugin/evm/vm.go
index 9f5607a..ac1eb56 100644
--- a/plugin/evm/vm.go
+++ b/plugin/evm/vm.go
@@ -185,6 +185,8 @@ type VM struct {
 	shutdownWg   sync.WaitGroup
 
 	fx secp256k1fx.Fx
+
+	minGasPrice params.GasPrice
 }
 
 func (vm *VM) getAtomicTx(block *types.Block) *Tx {
@@ -262,13 +264,34 @@ func (vm *VM) Initialize(
 	config.Miner.ManualMining = true
 	config.Miner.DisableUncle = true
 
-	// Set minimum price for mining and default gas price oracle value to the min
-	// gas price to prevent so transactions and blocks all use the correct fees
-	config.Miner.GasPrice = params.MinGasPrice
+	// Set minimum gas price and launch goroutine to sleep until
+	// network upgrade when the gas price must be changed
+	vm.minGasPrice = params.NewGasPrice(g.Config.ApricotBlockTimestamp)
+	if g.Config.ApricotBlockTimestamp == nil {
+		config.Miner.GasPrice = params.ApricotMinGasPrice
+		config.GPO.Default = params.ApricotMinGasPrice
+		config.TxPool.PriceLimit = params.ApricotMinGasPrice.Uint64()
+	} else {
+		apricotTime := time.Unix(g.Config.ApricotBlockTimestamp.Int64(), 0)
+		if time.Now().Before(apricotTime) {
+			config.Miner.GasPrice = params.LaunchMinGasPrice
+			config.GPO.Default = params.LaunchMinGasPrice
+			config.TxPool.PriceLimit = params.LaunchMinGasPrice.Uint64()
+
+			go func() {
+				time.Sleep(time.Until(apricotTime))
+
+				vm.chain.SetGasPrice(params.ApricotMinGasPrice)
+			}()
+		} else {
+			config.Miner.GasPrice = params.ApricotMinGasPrice
+			config.GPO.Default = params.ApricotMinGasPrice
+			config.TxPool.PriceLimit = params.ApricotMinGasPrice.Uint64()
+		}
+	}
+
 	config.RPCGasCap = vm.CLIConfig.RPCGasCap
 	config.RPCTxFeeCap = vm.CLIConfig.RPCTxFeeCap
-	config.GPO.Default = params.MinGasPrice
-	config.TxPool.PriceLimit = params.MinGasPrice.Uint64()
 	config.TxPool.NoLocals = true
 
 	if err := config.SetGCMode("archive"); err != nil {