加密包装

crypto/ecdsa.go

@@ -0,0 +1,100 @@
+package crypto
+
+import (
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"math/big"
+	"strconv"
+)
+
+type ecdsaOptions struct {
+	hashOptions
+	prv *ecdsa.PrivateKey
+	pub *ecdsa.PublicKey
+}
+
+type Option interface {
+	apply(*ecdsaOptions) error
+}
+
+type hash2Option interface {
+	apply(*hashOptions) error
+}
+
+type privateKeyOption []byte
+
+func (p privateKeyOption) apply(opts *ecdsaOptions) error {
+	block, _ := pem.Decode(p)
+	prv, err := x509.ParseECPrivateKey(block.Bytes)
+	if err != nil {
+		return err
+	}
+
+	opts.prv = prv
+
+	return nil
+}
+
+type publicKeyOption []byte
+
+func (p publicKeyOption) apply(opts *ecdsaOptions) error {
+	block, _ := pem.Decode(p)
+	pub, err := x509.ParsePKIXPublicKey(block.Bytes)
+	if err != nil {
+		return err
+	}
+
+	opts.pub = pub.(*ecdsa.PublicKey)
+	return nil
+}
+
+type hashOption crypto.Hash
+
+func (p hashOption) apply(opts *hashOptions) error {
+	opts.h = crypto.Hash(p)
+	return nil
+}
+
+func NewEcdsa(h Hash, opts ...Option) (*ecdsaOptions, error) {
+	i := &ecdsaOptions{}
+
+	sh := crypto.Hash(h)
+	if !sh.Available() {
+		return nil, errors.New("unknown hash value " + strconv.Itoa(int(h)))
+	}
+
+	i.h = sh
+
+	for _, v := range opts {
+		if err := v.apply(i); err != nil {
+			return nil, err
+		}
+	}
+
+	return i, nil
+}
+
+func WithHash2(h Hash) hash2Option {
+	return hashOption(h)
+}
+
+func ParsePrivateKey(pem []byte) Option {
+	return privateKeyOption(pem)
+}
+
+func ParsePublicKey(pem []byte) Option {
+	return publicKeyOption(pem)
+}
+
+func (opt *ecdsaOptions) Verify(msg, rText, sText []byte) bool {
+	var r, s big.Int
+	_ = r.UnmarshalText(rText)
+	_ = s.UnmarshalText(sText)
+
+	sum := opt.getHash(msg)
+
+	return ecdsa.Verify(opt.pub, sum, &r, &s)
+}