Merkle-ize X-Chain state

Signed-off-by: Joshua Kim <[email protected]>

Author: joshua-kim

database/memdb/db.go

@@ -5,6 +5,7 @@ package memdb
 
 import (
 	"context"
+	"fmt"
 	"slices"
 	"strings"
 	"sync"
@@ -38,6 +39,21 @@ func New() *Database {
 	return NewWithSize(DefaultSize)
 }
 
+// Copy returns a Database with the same key-value pairs as db
+func Copy(db *Database) (*Database, error) {
+	db.lock.Lock()
+	defer db.lock.Unlock()
+
+	result := New()
+	for k, v := range db.db {
+		if err := result.Put([]byte(k), v); err != nil {
+			return nil, fmt.Errorf("failed to insert key: %w", err)
+		}
+	}
+
+	return result, nil
+}
+
 // NewWithSize returns a map pre-allocated to the provided size with the
 // Database interface methods implemented.
 func NewWithSize(size int) *Database {

vms/avm/block/executor/block.go

@@ -80,15 +80,15 @@ func (b *Block) Verify(context.Context) error {
 		if err != nil {
 			txID := tx.ID()
 			b.manager.mempool.MarkDropped(txID, err)
-			return err
+			return fmt.Errorf("failed to syntactically verify tx %s: %w", txID, err)
 		}
 	}
 
 	// Verify that the parent exists.
 	parentID := b.Parent()
 	parent, err := b.manager.GetStatelessBlock(parentID)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to get parent %s: %w", parentID, err)
 	}
 
 	// Verify that currentBlkHeight = parentBlkHeight + 1.
@@ -105,7 +105,11 @@ func (b *Block) Verify(context.Context) error {
 
 	stateDiff, err := state.NewDiff(parentID, b.manager)
 	if err != nil {
-		return err
+		return fmt.Errorf(
+			"failed to initialize state diff on state at %s: %w",
+			parentID,
+			err,
+		)
 	}
 
 	parentChainTime := stateDiff.GetTimestamp()
@@ -138,7 +142,7 @@ func (b *Block) Verify(context.Context) error {
 		if err != nil {
 			txID := tx.ID()
 			b.manager.mempool.MarkDropped(txID, err)
-			return err
+			return fmt.Errorf("failed to semantically verify tx %s: %w", txID, err)
 		}
 
 		// Apply the txs state changes to the state.
@@ -155,7 +159,7 @@ func (b *Block) Verify(context.Context) error {
 		if err != nil {
 			txID := tx.ID()
 			b.manager.mempool.MarkDropped(txID, err)
-			return err
+			return fmt.Errorf("failed to execute tx %s: %w", txID, err)
 		}
 
 		// Verify that the transaction we just executed didn't consume inputs
@@ -188,7 +192,11 @@ func (b *Block) Verify(context.Context) error {
 	// already imported in a currently processing block.
 	err = b.manager.VerifyUniqueInputs(parentID, blockState.importedInputs)
 	if err != nil {
-		return err
+		return fmt.Errorf(
+			"failed to verify unique inputs on state at %s: %w",
+			parent,
+			err,
+		)
 	}
 
 	// Now that the block has been executed, we can add the block data to the
@@ -201,7 +209,7 @@ func (b *Block) Verify(context.Context) error {
 	return nil
 }
 
-func (b *Block) Accept(context.Context) error {
+func (b *Block) Accept(ctx context.Context) error {
 	blkID := b.ID()
 	defer b.manager.free(blkID)
 
@@ -246,12 +254,16 @@ func (b *Block) Accept(context.Context) error {
 		return err
 	}
 
+	checksum, err := b.manager.state.Checksum(ctx)
+	if err != nil {
+		return fmt.Errorf("failed to get checksum: %w", err)
+	}
 	b.manager.backend.Ctx.Log.Trace(
 		"accepted block",
 		zap.Stringer("blkID", blkID),
 		zap.Uint64("height", b.Height()),
 		zap.Stringer("parentID", b.Parent()),
-		zap.Stringer("checksum", b.manager.state.Checksum()),
+		zap.Stringer("checksum", checksum),
 	)
 	return nil
 }

vms/avm/block/executor/block_test.go

@@ -749,7 +749,7 @@ func TestBlockAccept(t *testing.T) {
 				// because we mock the call to shared memory
 				mockManagerState.EXPECT().CommitBatch().Return(nil, nil)
 				mockManagerState.EXPECT().Abort()
-				mockManagerState.EXPECT().Checksum().Return(ids.Empty)
+				mockManagerState.EXPECT().Checksum(gomock.Any()).Return(ids.Empty, nil)
 
 				mockSharedMemory := atomicmock.NewSharedMemory(ctrl)
 				mockSharedMemory.EXPECT().Apply(gomock.Any(), gomock.Any()).Return(nil)

vms/avm/block/executor/manager.go

@@ -51,7 +51,7 @@ type Manager interface {
 func NewManager(
 	mempool mempool.Mempool,
 	metrics metrics.Metrics,
-	state state.State,
+	state state.Interface,
 	backend *executor.Backend,
 	clk *mockable.Clock,
 	onAccept func(*txs.Tx) error,
@@ -72,7 +72,7 @@ func NewManager(
 
 type manager struct {
 	backend *executor.Backend
-	state   state.State
+	state   state.Interface
 	metrics metrics.Metrics
 	mempool mempool.Mempool
 	clk     *mockable.Clock

vms/avm/environment_test.go

@@ -113,7 +113,8 @@ func setup(tb testing.TB, c *envConfig) *environment {
 	}
 
 	vm := &VM{
-		Config: vmStaticConfig,
+		Config:                vmStaticConfig,
+		StateMigrationFactory: NoStateMigrationFactory{},
 	}
 
 	vmDynamicConfig := DefaultConfig

vms/avm/factory.go

@@ -16,5 +16,11 @@ type Factory struct {
 }
 
 func (f *Factory) New(logging.Logger) (interface{}, error) {
-	return &VM{Config: f.Config}, nil
+	return &VM{
+			Config: f.Config,
+			StateMigrationFactory: GForkStateMigrationFactory{
+				CommitFrequency: 1_000,
+			},
+		},
+		nil
 }