initial commit

internal/protectString/decrypt.go

@@ -0,0 +1,39 @@
+package protectString
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"encoding/hex"
+	"fmt"
+)
+
+func Decrypt(encryptedString string, keyString string) (decryptedString string) {
+	key, _ := hex.DecodeString(keyString)
+	enc, _ := hex.DecodeString(encryptedString)
+
+	//Create a new Cipher Block from the key
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		panic(err.Error())
+	}
+
+	//Create a new GCM
+	aesGCM, err := cipher.NewGCM(block)
+	if err != nil {
+		panic(err.Error())
+	}
+
+	//Get the nonce size
+	nonceSize := aesGCM.NonceSize()
+
+	//Extract the nonce from the encrypted data
+	nonce, ciphertext := enc[:nonceSize], enc[nonceSize:]
+
+	//Decrypt the data
+	plaintext, err := aesGCM.Open(nil, nonce, ciphertext, nil)
+	if err != nil {
+		panic(err.Error())
+	}
+
+	return fmt.Sprintf("%s", plaintext)
+}

internal/protectString/encrypt.go

@@ -0,0 +1,37 @@
+package protectString
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"io"
+)
+
+func Encrypt(stringToEncrypt string, keyString string) (encryptedString string) {
+	key, _ := hex.DecodeString(keyString)
+	plaintext := []byte(stringToEncrypt)
+
+	//Create a new Cipher Block from the key
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		panic(err.Error())
+	}
+
+	//Create a new GCM
+	aesGCM, err := cipher.NewGCM(block)
+	if err != nil {
+		panic(err.Error())
+	}
+
+	//Create a nonce. Nonce should be from GCM
+	nonce := make([]byte, aesGCM.NonceSize())
+	if _, err = io.ReadFull(rand.Reader, nonce); err != nil {
+		panic(err.Error())
+	}
+
+	//Encrypt the data using aesGCM.Seal
+	ciphertext := aesGCM.Seal(nonce, nonce, plaintext, nil)
+	return fmt.Sprintf("%x", ciphertext)
+}