You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
103 lines
2.4 KiB
103 lines
2.4 KiB
package merkle
|
|
|
|
import (
|
|
"bytes"
|
|
"fmt"
|
|
|
|
"github.com/tendermint/tendermint/crypto/tmhash"
|
|
tmmerkle "github.com/tendermint/tendermint/proto/tendermint/crypto/merkle"
|
|
)
|
|
|
|
const ProofOpValue = "simple:v"
|
|
|
|
// ValueOp takes a key and a single value as argument and
|
|
// produces the root hash. The corresponding tree structure is
|
|
// the SimpleMap tree. SimpleMap takes a Hasher, and currently
|
|
// Tendermint uses tmhash. SimpleValueOp should support
|
|
// the hash function as used in tmhash. TODO support
|
|
// additional hash functions here as options/args to this
|
|
// operator.
|
|
//
|
|
// If the produced root hash matches the expected hash, the
|
|
// proof is good.
|
|
type ValueOp struct {
|
|
// Encoded in ProofOp.Key.
|
|
key []byte
|
|
|
|
// To encode in ProofOp.Data
|
|
Proof *Proof `json:"proof"`
|
|
}
|
|
|
|
var _ ProofOperator = ValueOp{}
|
|
|
|
func NewValueOp(key []byte, proof *Proof) ValueOp {
|
|
return ValueOp{
|
|
key: key,
|
|
Proof: proof,
|
|
}
|
|
}
|
|
|
|
func ValueOpDecoder(pop tmmerkle.ProofOp) (ProofOperator, error) {
|
|
if pop.Type != ProofOpValue {
|
|
return nil, fmt.Errorf("unexpected ProofOp.Type; got %v, want %v", pop.Type, ProofOpValue)
|
|
}
|
|
var pbop tmmerkle.ValueOp // a bit strange as we'll discard this, but it works.
|
|
err := pbop.Unmarshal(pop.Data)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("decoding ProofOp.Data into ValueOp: %w", err)
|
|
}
|
|
|
|
sp, err := ProofFromProto(pbop.Proof)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return NewValueOp(pop.Key, sp), nil
|
|
}
|
|
|
|
func (op ValueOp) ProofOp() tmmerkle.ProofOp {
|
|
pbval := tmmerkle.ValueOp{
|
|
Key: op.key,
|
|
Proof: op.Proof.ToProto(),
|
|
}
|
|
bz, err := pbval.Marshal()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return tmmerkle.ProofOp{
|
|
Type: ProofOpValue,
|
|
Key: op.key,
|
|
Data: bz,
|
|
}
|
|
}
|
|
|
|
func (op ValueOp) String() string {
|
|
return fmt.Sprintf("ValueOp{%v}", op.GetKey())
|
|
}
|
|
|
|
func (op ValueOp) Run(args [][]byte) ([][]byte, error) {
|
|
if len(args) != 1 {
|
|
return nil, fmt.Errorf("expected 1 arg, got %v", len(args))
|
|
}
|
|
value := args[0]
|
|
hasher := tmhash.New()
|
|
hasher.Write(value) // does not error
|
|
vhash := hasher.Sum(nil)
|
|
|
|
bz := new(bytes.Buffer)
|
|
// Wrap <op.Key, vhash> to hash the KVPair.
|
|
encodeByteSlice(bz, op.key) // does not error
|
|
encodeByteSlice(bz, vhash) // does not error
|
|
kvhash := leafHash(bz.Bytes())
|
|
|
|
if !bytes.Equal(kvhash, op.Proof.LeafHash) {
|
|
return nil, fmt.Errorf("leaf hash mismatch: want %X got %X", op.Proof.LeafHash, kvhash)
|
|
}
|
|
|
|
return [][]byte{
|
|
op.Proof.ComputeRootHash(),
|
|
}, nil
|
|
}
|
|
|
|
func (op ValueOp) GetKey() []byte {
|
|
return op.key
|
|
}
|