service: remove SignRequest, VerifyRequest and accompanying code

service/sign.go

@@ -1,47 +0,0 @@
-package service
-
-import (
-	"crypto/ecdsa"
-
-	crypto "github.com/nspcc-dev/neofs-crypto"
-	"github.com/nspcc-dev/neofs-proto/internal"
-	"github.com/pkg/errors"
-)
-
-// ErrWrongSignature should be raised when wrong signature is passed into VerifyRequest.
-const ErrWrongSignature = internal.Error("wrong signature")
-
-// SignedRequest interface allows sign and verify requests.
-type SignedRequest interface {
-	PrepareData() ([]byte, error)
-	GetSignature() []byte
-	SetSignature([]byte)
-}
-
-// SignRequest with passed private key.
-func SignRequest(r SignedRequest, key *ecdsa.PrivateKey) error {
-	var signature []byte
-	if data, err := r.PrepareData(); err != nil {
-		return err
-	} else if signature, err = crypto.Sign(key, data); err != nil {
-		return errors.Wrap(err, "could not sign data")
-	}
-
-	r.SetSignature(signature)
-
-	return nil
-}
-
-// VerifyRequest by passed public keys.
-func VerifyRequest(r SignedRequest, keys ...*ecdsa.PublicKey) bool {
-	data, err := r.PrepareData()
-	if err != nil {
-		return false
-	}
-	for i := range keys {
-		if err := crypto.Verify(keys[i], data, r.GetSignature()); err == nil {
-			return true
-		}
-	}
-	return false
-}