package crypto import ( "errors" "fmt" "github.com/nspcc-dev/neo-go/pkg/core/interop" "github.com/nspcc-dev/neo-go/pkg/crypto" "github.com/nspcc-dev/neo-go/pkg/crypto/hash" "github.com/nspcc-dev/neo-go/pkg/crypto/keys" "github.com/nspcc-dev/neo-go/pkg/vm" "github.com/nspcc-dev/neo-go/pkg/vm/stackitem" ) // ECDSAVerify checks ECDSA signature. func ECDSAVerify(ic *interop.Context, v *vm.VM) error { msg := getMessage(ic, v.Estack().Pop().Item()) hashToCheck := hash.Sha256(msg).BytesBE() keyb := v.Estack().Pop().Bytes() signature := v.Estack().Pop().Bytes() pkey, err := keys.NewPublicKeyFromBytes(keyb) if err != nil { return err } res := pkey.Verify(signature, hashToCheck) v.Estack().PushVal(res) return nil } // ECDSACheckMultisig checks multiple ECDSA signatures at once. func ECDSACheckMultisig(ic *interop.Context, v *vm.VM) error { msg := getMessage(ic, v.Estack().Pop().Item()) hashToCheck := hash.Sha256(msg).BytesBE() pkeys, err := v.Estack().PopSigElements() if err != nil { return fmt.Errorf("wrong parameters: %s", err.Error()) } sigs, err := v.Estack().PopSigElements() if err != nil { return fmt.Errorf("wrong parameters: %s", err.Error()) } // It's ok to have more keys than there are signatures (it would // just mean that some keys didn't sign), but not the other way around. if len(pkeys) < len(sigs) { return errors.New("more signatures than there are keys") } sigok := vm.CheckMultisigPar(v, hashToCheck, pkeys, sigs) v.Estack().PushVal(sigok) return nil } func getMessage(ic *interop.Context, item stackitem.Item) []byte { var msg []byte switch val := item.(type) { case *stackitem.Interop: msg = val.Value().(crypto.Verifiable).GetSignedPart() case stackitem.Null: msg = ic.Container.GetSignedPart() default: var err error if msg, err = val.TryBytes(); err != nil { return nil } } return msg }