Initial commit

rest/middlewares/secure.go

@@ -0,0 +1,86 @@
+// scrypt.go
+package middlewares
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"log"
+	"time"
+
+	"golang.org/x/crypto/scrypt"
+)
+
+func Encrypt(key, data []byte) ([]byte, error) {
+	key, salt, err := DeriveKey(key, nil)
+	if err != nil {
+		return nil, err
+	}
+	blockCipher, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	gcm, err := cipher.NewGCM(blockCipher)
+	if err != nil {
+		return nil, err
+	}
+	nonce := make([]byte, gcm.NonceSize())
+	if _, err = rand.Read(nonce); err != nil {
+		return nil, err
+	}
+	ciphertext := gcm.Seal(nonce, nonce, data, nil)
+	ciphertext = append(ciphertext, salt...)
+	return ciphertext, nil
+}
+func Decrypt(key, data []byte) ([]byte, error) {
+	salt, data := data[len(data)-32:], data[:len(data)-32]
+	key, _, err := DeriveKey(key, salt)
+	if err != nil {
+		return nil, err
+	}
+	blockCipher, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	gcm, err := cipher.NewGCM(blockCipher)
+	if err != nil {
+		return nil, err
+	}
+	nonce, ciphertext := data[:gcm.NonceSize()], data[gcm.NonceSize():]
+	plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
+	if err != nil {
+		return nil, err
+	}
+	return plaintext, nil
+}
+func DeriveKey(password, salt []byte) ([]byte, []byte, error) {
+	if salt == nil {
+		salt = make([]byte, 32)
+		if _, err := rand.Read(salt); err != nil {
+			return nil, nil, err
+		}
+	}
+	key, err := scrypt.Key(password, salt, 1048576, 8, 1, 32)
+	if err != nil {
+		return nil, nil, err
+	}
+	return key, salt, nil
+}
+func main() {
+	var (
+		password = []byte("mysecretpassword")
+		data     = []byte(fmt.Sprintf("%v", time.Now().Unix()))
+	)
+	ciphertext, err := Encrypt(password, data)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("ciphertext: %s\n", hex.EncodeToString(ciphertext))
+	plaintext, err := Decrypt(password, ciphertext)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("plaintext: %s\n", plaintext)
+}