package signature import ( "crypto/ecdsa" "github.com/nspcc-dev/neofs-api-go/v2/refs" crypto "github.com/nspcc-dev/neofs-crypto" ) type DataSource interface { ReadSignedData([]byte) ([]byte, error) SignedDataSize() int } type DataWithSignature interface { DataSource GetSignature() *refs.Signature SetSignature(*refs.Signature) } type SignOption func(*cfg) type KeySignatureHandler func(*refs.Signature) type KeySignatureSource func() *refs.Signature func SignDataWithHandler(key *ecdsa.PrivateKey, src DataSource, handler KeySignatureHandler, opts ...SignOption) error { if key == nil { return crypto.ErrEmptyPrivateKey } cfg := defaultCfg() for i := range opts { opts[i](cfg) } data, err := readSignedData(cfg, src) if err != nil { return err } sigData, err := sign(cfg, key, data) if err != nil { return err } sig := new(refs.Signature) sig.SetScheme(cfg.scheme) sig.SetKey(crypto.MarshalPublicKey(&key.PublicKey)) sig.SetSign(sigData) handler(sig) return nil } func VerifyDataWithSource(dataSrc DataSource, sigSrc KeySignatureSource, opts ...SignOption) error { cfg := defaultCfg() for i := range opts { opts[i](cfg) } data, err := readSignedData(cfg, dataSrc) if err != nil { return err } return verify(cfg, data, sigSrc()) } func SignData(key *ecdsa.PrivateKey, v DataWithSignature, opts ...SignOption) error { return SignDataWithHandler(key, v, v.SetSignature, opts...) } func VerifyData(src DataWithSignature, opts ...SignOption) error { return VerifyDataWithSource(src, src.GetSignature, opts...) } func readSignedData(cfg *cfg, src DataSource) ([]byte, error) { size := src.SignedDataSize() if cfg.buffer == nil || cap(cfg.buffer) < size { cfg.buffer = make([]byte, size) } else { cfg.buffer = cfg.buffer[:size] } return src.ReadSignedData(cfg.buffer) }