restruc my codebase

utils/crypto.go

@@ -1 +1,79 @@
 package utils
+
+import (
+	"bytes"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+)
+
+func EncryptAES(data []byte, key []byte) ([]byte, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	// Generate a random IV (Initialization Vector)
+	iv := make([]byte, aes.BlockSize)
+	if _, err := rand.Read(iv); err != nil {
+		fmt.Println("error generating IV:", err)
+	}
+
+	// Pad the data to a multiple of the block size
+	data = pkcs7Pad(data, aes.BlockSize)
+
+	// Create a CBC mode cipher block
+	mode := cipher.NewCBCEncrypter(block, iv)
+
+	// Encrypt the data
+	ciphertext := make([]byte, len(data))
+	mode.CryptBlocks(ciphertext, data)
+
+	// Prepend the IV to the ciphertext
+	ciphertext = append(iv, ciphertext...)
+
+	return ciphertext, nil
+}
+
+func DecryptAES(base64Ciphertext string, key []byte) ([]byte, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	// Decode base64
+	ciphertext, err := base64.StdEncoding.DecodeString(base64Ciphertext)
+	if err != nil {
+		fmt.Println("error decoding base64:", err)
+	}
+
+	// Extract the IV from the ciphertext
+	iv := ciphertext[:aes.BlockSize]
+	ciphertext = ciphertext[aes.BlockSize:]
+
+	// Create a CBC mode cipher block
+	mode := cipher.NewCBCDecrypter(block, iv)
+
+	// Decrypt the data
+	mode.CryptBlocks(ciphertext, ciphertext)
+
+	// Remove padding
+	ciphertext = pkcs7Unpad(ciphertext)
+
+	return ciphertext, nil
+}
+
+// pkcs7Pad pads the input to a multiple of blockSize using PKCS#7 padding
+func pkcs7Pad(data []byte, blockSize int) []byte {
+	padding := blockSize - len(data)%blockSize
+	padText := bytes.Repeat([]byte{byte(padding)}, padding)
+	return append(data, padText...)
+}
+
+// pkcs7Unpad removes PKCS#7 padding from the input
+func pkcs7Unpad(data []byte) []byte {
+	padding := int(data[len(data)-1])
+	return data[:len(data)-padding]
+}