lotus/lib/sigs/sigs.go
2020-02-14 15:14:39 +01:00

105 lines
2.6 KiB
Go

package sigs
import (
"context"
"fmt"
"github.com/filecoin-project/go-address"
"github.com/filecoin-project/specs-actors/actors/crypto"
"go.opencensus.io/trace"
"golang.org/x/xerrors"
"github.com/filecoin-project/lotus/chain/types"
)
// Sign takes in signature type, private key and message. Returns a signature for that message.
// Valid sigTypes are: "secp256k1" and "bls"
func Sign(sigType crypto.SigType, privkey []byte, msg []byte) (*crypto.Signature, error) {
sv, ok := sigs[sigType]
if !ok {
return nil, fmt.Errorf("cannot sign message with signature of unsupported type: %s", sigType)
}
sb, err := sv.Sign(privkey, msg)
if err != nil {
return nil, err
}
return &crypto.Signature{
Type: sigType,
Data: sb,
}, nil
}
// Verify verifies signatures
func Verify(sig *crypto.Signature, addr address.Address, msg []byte) error {
if sig == nil {
return xerrors.Errorf("signature is nil")
}
if addr.Protocol() == address.ID {
return fmt.Errorf("must resolve ID addresses before using them to verify a signature")
}
sv, ok := sigs[sig.Type]
if !ok {
return fmt.Errorf("cannot verify signature of unsupported type: %s", sig.Type)
}
return sv.Verify(sig.Data, addr, msg)
}
// Generate generates private key of given type
func Generate(sigType crypto.SigType) ([]byte, error) {
sv, ok := sigs[sigType]
if !ok {
return nil, fmt.Errorf("cannot generate private key of unsupported type: %s", sigType)
}
return sv.GenPrivate()
}
// ToPublic converts private key to public key
func ToPublic(sigType crypto.SigType, pk []byte) ([]byte, error) {
sv, ok := sigs[sigType]
if !ok {
return nil, fmt.Errorf("cannot generate public key of unsupported type: %s", sigType)
}
return sv.ToPublic(pk)
}
func CheckBlockSignature(blk *types.BlockHeader, ctx context.Context, worker address.Address) error {
_, span := trace.StartSpan(ctx, "checkBlockSignature")
defer span.End()
if blk.BlockSig == nil {
return xerrors.New("block signature not present")
}
sigb, err := blk.SigningBytes()
if err != nil {
return xerrors.Errorf("failed to get block signing bytes: %w", err)
}
_ = sigb
return Verify(blk.BlockSig, worker, sigb)
}
// SigShim is used for introducing signature functions
type SigShim interface {
GenPrivate() ([]byte, error)
ToPublic(pk []byte) ([]byte, error)
Sign(pk []byte, msg []byte) ([]byte, error)
Verify(sig []byte, a address.Address, msg []byte) error
}
var sigs map[crypto.SigType]SigShim
// RegisterSig should be only used during init
func RegisterSignature(typ crypto.SigType, vs SigShim) {
if sigs == nil {
sigs = make(map[crypto.SigType]SigShim)
}
sigs[typ] = vs
}