# Authentication
## Encryption Guidelines
All API requests must be encrypted using AES (ECB mode, PKCS5Padding) before transmission.
This page provides the required imports, encryption/decryption utilities, and essential developer tips to ensure proper integration.
```java
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.util.Arrays;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;
```
## Encrypting Request Payloads
Use the encrypt method to convert plaintext request data into an AES-encrypted Base64 string.
## Encrypt Function
```java
public static String encrypt(String strToEncrypt, String secret) {
try {
if (CommonUtil.isEmpty(strToEncrypt)) return "";
SecretKeySpec secretKeySpec = getKeySpec(secret);
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
byte[] encryptedBytes = cipher.doFinal(strToEncrypt.getBytes(StandardCharsets.UTF_8));
return Base64.getEncoder().encodeToString(encryptedBytes);
} catch (Exception e) {
LOGGER.error("Error while encrypting: " + e.getMessage());
return null;
}
}
```
## Generate SecretKeySpec
The following utility converts the provided secret key into a 128-bit AES key using SHA-256 hashing.
```java
private static SecretKeySpec getKeySpec(String secretKey) throws NoSuchAlgorithmException {
byte[] key = secretKey.getBytes(StandardCharsets.UTF_8);
MessageDigest sha = MessageDigest.getInstance("SHA-256");
key = sha.digest(key);
key = Arrays.copyOf(key, 16); // Use first 128 bits for AES-128
return new SecretKeySpec(key, "AES");
}
```
## Decrypt Function
Use the following method to decrypt API responses that return AES-encrypted data.
```java
public static String decrypt(String strToDecrypt, String secret) {
try {
if (CommonUtil.isEmpty(strToDecrypt)) return "";
SecretKeySpec secretKeySpec = getKeySpec(secret);
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5PADDING");
cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
return new String(cipher.doFinal(Base64.getDecoder().decode(strToDecrypt)));
} catch (Exception e) {
LOGGER.error("Error while decrypting: " + e.getMessage());
return null;
}
}
```
## Encryption Secret Key
Use the following secret key for all encryption and decryption:
```java
JaAnE1431042241474139605aholD
```
## Developer Tips
Remove double quotes from plaintext before encrypting
Avoid trailing whitespaces in the encrypted string
Ensure encrypted payloads are passed in the correct request field (e.g., payload, requestData)