lotus/lib/sigs/delegated/init.go
2022-12-15 16:47:06 -05:00

77 lines
1.6 KiB
Go

package delegated
import (
"fmt"
"golang.org/x/crypto/sha3"
"github.com/filecoin-project/go-address"
gocrypto "github.com/filecoin-project/go-crypto"
"github.com/filecoin-project/go-state-types/builtin"
crypto1 "github.com/filecoin-project/go-state-types/crypto"
"github.com/filecoin-project/lotus/lib/sigs"
)
type delegatedSigner struct{}
func (delegatedSigner) GenPrivate() ([]byte, error) {
priv, err := gocrypto.GenerateKey()
if err != nil {
return nil, err
}
return priv, nil
}
func (delegatedSigner) ToPublic(pk []byte) ([]byte, error) {
return gocrypto.PublicKey(pk), nil
}
func (s delegatedSigner) Sign(pk []byte, msg []byte) ([]byte, error) {
hasher := sha3.NewLegacyKeccak256()
hasher.Write(msg)
hashSum := hasher.Sum(nil)
sig, err := gocrypto.Sign(pk, hashSum)
if err != nil {
return nil, err
}
return sig, nil
}
func (delegatedSigner) Verify(sig []byte, a address.Address, msg []byte) error {
hasher := sha3.NewLegacyKeccak256()
hasher.Write(msg)
hash := hasher.Sum(nil)
pubk, err := gocrypto.EcRecover(hash, sig)
if err != nil {
return err
}
// if we get an uncompressed public key (that's what we get from the library,
// but putting this check here for defensiveness), strip the prefix
if pubk[0] == 0x04 {
pubk = pubk[1:]
}
hasher.Reset()
hasher.Write(pubk)
addrHash := hasher.Sum(nil)
maybeaddr, err := address.NewDelegatedAddress(builtin.EthereumAddressManagerActorID, addrHash[12:])
if err != nil {
return err
}
if maybeaddr != a {
return fmt.Errorf("signature did not match")
}
return nil
}
func init() {
sigs.RegisterSignature(crypto1.SigTypeDelegated, delegatedSigner{})
}