I was looking to encrypt data between a PHP server and a Java Client. Individually the code works fine and I would like to stick with OpenSSL on the PHP server.
Do any of you see anything that I am missing here as I get an error when trying to decode the PHP encrypted string:
PHP:
<?php
$iv = 'fedcba9876543210'; #Same as in JAVA
$key = '0123456789abcdef'; #Same as in JAVA
$ciphers = openssl_get_cipher_methods(FALSE);
$ciphers_and_aliases = openssl_get_cipher_methods(true);
$cipher_aliases = array_diff($ciphers_and_aliases, $ciphers);
print_r($ciphers);
//print_r($cipher_aliases);
// DEFINE our cipher
define('AES_CBC', 'aes-128-cbc');
// Generate a 256-bit encryption key
// This should be stored somewhere instead of recreating it each time
$encryption_key = "test_key";
// Generate an initialization vector
// This *MUST* be available for decryption as well
//$iv = openssl_random_pseudo_bytes(openssl_cipher_iv_length(AES_CBC));
// Create some data to encrypt
$data = "Hello World!!!";
$data_b64= base64_encode($data);
echo "Before encryption: $data<br><br>Before Base64: $data_b64<br><br>";
// Encrypt $data using aes-256-cbc cipher with the given encryption key and
// our initialization vector. The 0 gives us the default options, but can
// be changed to OPENSSL_RAW_DATA or OPENSSL_ZERO_PADDING
$encrypted = openssl_encrypt($data_b64, AES_CBC, $encryption_key, 0, $iv);
$len = strlen($encrypted);
echo "Encrypted Len: $len <br><br>";
$encrypted64 = base64_encode($encrypted);
echo "Encrypted b64: $encrypted64<br><br>";
// If we lose the $iv variable, we can't decrypt this, so:
// - $encrypted is already base64-encoded from openssl_encrypt
// - Append a separator that we know won't exist in base64, ":"
// - And then append a base64-encoded $iv
$encrypted = $encrypted64 . ':' . base64_encode($iv);
echo "Encrypted: $encrypted<br><br>";
// To decrypt, separate the encrypted data from the initialization vector ($iv).
$parts = explode(':', $encrypted);
// $parts[0] = encrypted data
// $parts[1] = base-64 encoded initialization vector
// Don't forget to base64-decode the $iv before feeding it back to
//openssl_decrypt
$decrypted64 = openssl_decrypt(base64_decode($parts[0]), AES_CBC, $encryption_key, 0, base64_decode($parts[1]));
$decrypted = base64_decode($decrypted64);
echo "Decrypted: $decrypted\n";
?>
PHP output:
Before encryption: Hello World!!!
Before Base64: SGVsbG8gV29ybGQhISE=
Encrypted Len: 44
Encrypted b64: U21yMVRGQTdROVc3TWJ1Wm1HUTBhMmZmenlIN2tvdWQ5SHA5ekVxUmp5az0=
Encrypted: U21yMVRGQTdROVc3TWJ1Wm1HUTBhMmZmenlIN2tvdWQ5SHA5ekVxUmp5az0=:ZmVkY2JhOTg3NjU0MzIxMA==
Decrypted: Hello World!!!
Java Code:
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;
import java.security.*;
public class Sandbox {
public static String encrypt(String key, String initVector, String value) {
try {
IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
byte[] encrypted = cipher.doFinal(Base64.getEncoder().encode(value.getBytes()));
System.out.println("encrypted string: "
+ Base64.getEncoder().encodeToString(encrypted));
return Base64.getEncoder().encodeToString(encrypted);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
public static String decrypt(String key, String initVector, String encrypted) {
try {
IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);
byte[] temp = Base64.getDecoder().decode(encrypted);
System.out.println((new String(temp)).length());
byte[] original = cipher.doFinal(temp);
original = Base64.getDecoder().decode(original);
return new String(original);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
public static void main(String[] args) {
String key = "0123456789abcdef"; // 128 bit key
String initVector = "fedcba9876543210"; // 16 bytes IV
// for (Provider provider : Security.getProviders()) {
// System.out.println(provider.getName());
// for (String key2 : provider.stringPropertyNames()) {
// System.out.println("\t" + key2 + "\t" + provider.getProperty(key2));
// }
// }
System.out.println(decrypt(key, initVector,
encrypt(key, initVector, "Hello World!!!")));
System.out.println(decrypt(key, initVector, "R090NDcvclAyY2E1cmxLWG9kSGlnUktHdEI5U05sRGxNdWF4NFFjUUV0OD0="));
}
}
Java Output:
>
30
Hello World!!!
44
null
javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher
at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:913)
at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:824)
at com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:436)
at javax.crypto.Cipher.doFinal(Cipher.java:2165)
at Sandbox.decrypt(Sandbox.java:43)
at Sandbox.main(Sandbox.java:67)
BUILD SUCCESSFUL (total time: 1 second)
