zkbnb-smt

zkbnb-smt is an implementation code library based on the concept of SparseMerkleTree, which implements the concepts of data persistence and data compression.

For an overview, see the design.

Installation

go get github.com/bnb-chain/zkbnb-smt@latest

Quickstart

package main

import (
	"crypto/sha256"
	"fmt"

	bsmt "github.com/bnb-chain/zkbnb-smt"
	"github.com/bnb-chain/zkbnb-smt/database/memory"
)

func main() {
	db := memory.NewMemoryDB()
	hasher := bsmt.NewHasher(sha256.New())
	nilHash := hasher.Hash([]byte("nilHash"))
	maxDepth := uint8(8)

	smt, err := bsmt.NewBNBSparseMerkleTree(hasher, db, maxDepth, nilHash)
	if err != nil {
		fmt.Println(err)
		return
	}

	key1 := uint64(1)
	key2 := uint64(2)
	key3 := uint64(23)
	val1 := hasher.Hash([]byte("test1"))
	val2 := hasher.Hash([]byte("test2"))
	val3 := hasher.Hash([]byte("test3"))
	smt.Set(key1, val1)
	smt.Set(key2, val2)
	smt.Set(key3, val3)

	version1, err := smt.Commit(nil)
	if err != nil {
		fmt.Println(err)
		return
	}

	_, err = smt.Get(key1, &version1)
	if err != nil {
		fmt.Println(err)
		return
	}

	_, err = smt.Get(key2, &version1)
	if err != nil {
		fmt.Println(err)
		return
	}
	_, err = smt.Get(key3, &version1)
	if err != nil {
		fmt.Println(err)
		return
	}

	proof, err := smt.GetProof(key1)
	if err != nil {
		fmt.Println(err)
		return
	}
	if !smt.VerifyProof(key1, proof) {
		fmt.Println("verify proof failed")
		return
	}
}