Инициализация библиотеки

2022-07-30 18:30:44 +10:00
commit badb5f0627
5 changed files with 218 additions and 0 deletions
--- a/rsa.go
+++ b/rsa.go
@@ -0,0 +1,150 @@
+package ciphers
+
+import (
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"hash"
+)
+
+var (
+	ErrPubKeyNotCorrect = errors.New("rsa public key is not correct")
+)
+
+// GenerateKeyPair generates a new key pair
+func GenerateKeyPair(bits int) (*rsa.PrivateKey, error) {
+	privkey, err := rsa.GenerateKey(rand.Reader, bits)
+	if err != nil {
+		return nil, err
+	}
+	return privkey, nil
+}
+
+// PrivateKeyToBytes private key to bytes
+func PrivateKeyToBytes(priv *rsa.PrivateKey) []byte {
+	privBytes := pem.EncodeToMemory(
+		&pem.Block{
+			Type:  "RSA PRIVATE KEY",
+			Bytes: x509.MarshalPKCS1PrivateKey(priv),
+		},
+	)
+
+	return privBytes
+}
+
+// PublicKeyToBytes public key to bytes
+func PublicKeyToBytes(pub *rsa.PrivateKey) ([]byte, error) {
+	pubASN1, err := x509.MarshalPKIXPublicKey(&pub.PublicKey)
+	if err != nil {
+		return nil, err
+	}
+
+	pubBytes := pem.EncodeToMemory(&pem.Block{
+		Type:  "PUBLIC KEY",
+		Bytes: pubASN1,
+	})
+
+	return pubBytes, nil
+}
+
+func BytesRsaKeyToGo(priv, pub []byte) (*rsa.PrivateKey, error) {
+
+	key, err := BytesToPrivateKey(priv)
+	if err != nil {
+		return nil, err
+	}
+
+	pubKey, err := BytesToPublicKey(pub)
+	if err != nil {
+		return nil, err
+	}
+
+	key.PublicKey = rsa.PublicKey{
+		N: pubKey.N,
+		E: pubKey.E,
+	}
+
+	return key, nil
+}
+
+//
+func BytesPublicKeyToGo(pub []byte) (*rsa.PublicKey, error) {
+
+	pubKey, err := BytesToPublicKey(pub)
+	if err != nil {
+		return nil, err
+	}
+
+	return &rsa.PublicKey{
+		N: pubKey.N,
+		E: pubKey.E,
+	}, nil
+}
+
+// BytesToPrivateKey bytes to private key
+func BytesToPrivateKey(priv []byte) (*rsa.PrivateKey, error) {
+	block, _ := pem.Decode(priv)
+	enc := x509.IsEncryptedPEMBlock(block)
+	b := block.Bytes
+	var err error
+	if enc {
+		//log.Println("is encrypted pem block")
+		b, err = x509.DecryptPEMBlock(block, nil)
+		if err != nil {
+			return nil, err
+		}
+	}
+	key, err := x509.ParsePKCS1PrivateKey(b)
+	if err != nil {
+		return nil, err
+	}
+	return key, nil
+}
+
+// BytesToPublicKey bytes to public key
+func BytesToPublicKey(pub []byte) (*rsa.PublicKey, error) {
+	block, _ := pem.Decode(pub)
+	enc := x509.IsEncryptedPEMBlock(block)
+	b := block.Bytes
+	var err error
+	if enc {
+		//log.Println("is encrypted pem block")
+		b, err = x509.DecryptPEMBlock(block, nil)
+		if err != nil {
+			return nil, err
+		}
+	}
+	ifc, err := x509.ParsePKIXPublicKey(b)
+	if err != nil {
+		return nil, err
+	}
+	key, ok := ifc.(*rsa.PublicKey)
+	if !ok {
+		return nil, ErrPubKeyNotCorrect
+	}
+	return key, nil
+}
+
+// EncryptWithPublicKey OAEP encrypts data with public key
+func EncryptWithPublicKeyOAEP(hash hash.Hash, msg []byte, pub *rsa.PublicKey) ([]byte, error) {
+	//hash := sha512.New()
+	//hash := sha1.New()
+	ciphertext, err := rsa.EncryptOAEP(hash, rand.Reader, pub, msg, nil)
+	if err != nil {
+		return nil, err
+	}
+	return ciphertext, nil
+}
+
+// DecryptWithPrivateKey OAEP decrypts data with private key
+func DecryptWithPrivateKeyOAEP(hash hash.Hash, ciphertext []byte, priv *rsa.PrivateKey) ([]byte, error) {
+	//hash := sha512.New()
+	//hash := sha1.New()
+	plaintext, err := rsa.DecryptOAEP(hash, rand.Reader, priv, ciphertext, nil)
+	if err != nil {
+		return nil, err
+	}
+	return plaintext, nil
+}