Add encrypt and decrypt function

.gitignore

@@ -1,3 +1,4 @@
 go-demo/app-1
 go-demo-4/data.json
-go-demo-4/.env
+go-demo-4/.env*
+go-demo-4/*.vault

go-demo-4/encrypter/encrypter.go

@@ -1,6 +1,12 @@
 package encrypter
 
-import "os"
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"io"
+	"os"
+)
 
 type Encrypter struct {
 	Key string
@@ -16,10 +22,37 @@ func NewEncrypter() *Encrypter {
 	}
 }
 
-func (enc *Encrypter) Encrypt(plainStr string) string {
+func (enc *Encrypter) Encrypt(plainStr []byte) []byte {
-	return ""
+	block, err := aes.NewCipher([]byte(enc.Key))
+	if err != nil {
+		panic(err.Error())
+	}
+	aesGCM, err := cipher.NewGCM(block)
+	if err != nil {
+		panic(err.Error())
+	}
+	nonce := make([]byte, aesGCM.NonceSize())
+	_, err = io.ReadFull(rand.Reader, nonce)
+	if err != nil {
+		panic(err.Error())
+	}
+	return aesGCM.Seal(nonce, nonce, plainStr, nil)
 }
 
-func (enc *Encrypter) Decrypt(encryptedStr string) string {
+func (enc *Encrypter) Decrypt(encryptedStr []byte) []byte {
-	return ""
+	block, err := aes.NewCipher([]byte(enc.Key))
+	if err != nil {
+		panic(err.Error())
+	}
+	aesGCM, err := cipher.NewGCM(block)
+	if err != nil {
+		panic(err.Error())
+	}
+	nonceSize := aesGCM.NonceSize()
+	nonce, cipherText := encryptedStr[:nonceSize], encryptedStr[nonceSize:]
+	plainText, err := aesGCM.Open(nil, nonce, cipherText, nil)
+	if err != nil {
+		panic(err.Error())
+	}
+	return plainText
 }

go-demo-4/main.go

@@ -43,7 +43,7 @@ func main() {
 	if err != nil {
 		output.PrintError("Не удалось найти файл .env")
 	}
-	vault := account.NewVault(files.NewJsonDb("data.json"), *encrypter.NewEncrypter())
+	vault := account.NewVault(files.NewJsonDb("data.vault"), *encrypter.NewEncrypter())
 	counter := menuCounter()
 Menu:
 	for {