initial commit

pkg/utils/crypto.go

@@ -0,0 +1,70 @@
+package utils
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/base64"
+	"errors"
+	"io"
+)
+
+func EncryptAES(data string, key string) (string, error) {
+	encrypted, err := EncryptBytesAES([]byte(data), key)
+	if err != nil {
+		return "", err
+	}
+
+	return base64.URLEncoding.EncodeToString(encrypted), nil
+}
+
+func EncryptBytesAES(plainText []byte, key string) ([]byte, error) {
+
+	block, err := aes.NewCipher([]byte(key))
+	if err != nil {
+		return nil, err
+	}
+
+	cipherText := make([]byte, aes.BlockSize+len(plainText))
+	iv := cipherText[:aes.BlockSize]
+	if _, err = io.ReadFull(rand.Reader, iv); err != nil {
+		return nil, err
+	}
+
+	stream := cipher.NewCFBEncrypter(block, iv)
+	stream.XORKeyStream(cipherText[aes.BlockSize:], plainText)
+
+	return cipherText, nil
+}
+
+func DecryptAES(data string, key string) (string, error) {
+	text, err := base64.URLEncoding.DecodeString(data)
+	if err != nil {
+		return "", nil
+	}
+	decrypted, err := DecryptBytesAES(text, key)
+	if err != nil {
+		return "", err
+	}
+	return string(decrypted), nil
+}
+
+func DecryptBytesAES(cipherText []byte, key string) ([]byte, error) {
+
+	block, err := aes.NewCipher([]byte(key))
+	if err != nil {
+		return nil, err
+	}
+
+	if len(cipherText) < aes.BlockSize {
+		err = errors.New("Ciphertext block size is too short!")
+		return nil, err
+	}
+	iv := cipherText[:aes.BlockSize]
+	cipherText = cipherText[aes.BlockSize:]
+
+	stream := cipher.NewCFBDecrypter(block, iv)
+	stream.XORKeyStream(cipherText, cipherText)
+
+	return cipherText, err
+}