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Forked from casimir/1_output.md
Created July 28, 2022 12:05
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AES-256 examples

Informations

cipher key: 0123456789abcdef0123456789abcdef
IV: 0123456789ABCDEF
padding character: fs (ASCII=34 -> FILE SEPARATOR)

Expected output

secret message: this information is confidential, for your eyes only
    encrypted > K7aToyGnmyxFF+GHzMOsArYMibOqtWn3J9DxJGN2CczFIwc12/dAty4eV5tRtvPeLEC2cSiRtrtGBHuET8buSQ==
    decrypted > this information is confidential, for your eyes only
SUCCESS
import java.security.MessageDigest;
import java.util.Arrays;
import java.util.Base64;
import java.nio.charset.StandardCharsets;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class AES {
static byte[] CIPHER_KEY = "0123456789abcdef0123456789abcdef".getBytes(StandardCharsets.UTF_8);
static byte[] IV = "1234567890ABCDEF".getBytes(StandardCharsets.UTF_8);
static char PADDING_CHAR = '\034';
public static String encrypt(String text) throws Exception {
Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE");
SecretKeySpec key = new SecretKeySpec(CIPHER_KEY, "AES");
cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(IV));
int paddingSize = 16 - text.length() % 16;
String padding = String.format("%0" + paddingSize + "d", 0).replace('0', PADDING_CHAR);
String padded = text + padding;
byte[] encrypted = cipher.doFinal(padded.getBytes(StandardCharsets.UTF_8));
return Base64.getEncoder().encodeToString(encrypted);
}
public static String decrypt(String data) throws Exception {
Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE");
SecretKeySpec key = new SecretKeySpec(CIPHER_KEY, "AES");
cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(IV));
byte[] encrypted = Base64.getDecoder().decode(data);
String padded = new String(cipher.doFinal(encrypted), StandardCharsets.UTF_8);
return padded.replaceAll(PADDING_CHAR + "+$", "");
}
public static void main(String[] args) {
try {
String message = "this information is confidential, for your eyes only";
System.out.println("secret message: " + message);
String encrypted_message = encrypt(message);
System.out.println(" encrypted > " + encrypted_message);
String decrypted_message = decrypt(encrypted_message);
System.out.println(" decrypted > " + decrypted_message);
if (message.equals(decrypted_message)) {
System.out.println("SUCCESS");
} else {
System.out.println("FAILED");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
<?php
define('CIPHER_KEY', "0123456789abcdef0123456789abcdef");
define('IV', "1234567890ABCDEF");
define('PADDING_CHAR', "\034");
function encrypt($text)
{
$padded = $text . str_repeat(PADDING_CHAR, (16 - strlen($text) % 16));
return openssl_encrypt($padded, "AES-256-CBC", CIPHER_KEY, OPENSSL_ZERO_PADDING, IV);
}
function decrypt($data)
{
$padded = openssl_decrypt($data, "AES-256-CBC", CIPHER_KEY, OPENSSL_ZERO_PADDING, IV);
return rtrim($padded, PADDING_CHAR);
}
$message = "this information is confidential, for your eyes only";
echo "secret message: " . $message . "\n";
$encrypted_message = encrypt($message);
echo " encrypted > " . $encrypted_message . "\n";
$decrypted_message = decrypt($encrypted_message);
echo " decrypted > " . $decrypted_message . "\n";
echo $message === $decrypted_message ? "SUCCESS" : "FAILED" . "\n";
?>
# Dependencies: PyCrypto -> `pip install pycrypto`
from base64 import b64decode, b64encode
from Crypto.Cipher import AES
CIPHER_KEY = "0123456789abcdef0123456789abcdef"
IV = b"1234567890ABCDEF"
PADDING_CHAR = b"\034"
def encrypt(text):
aes = AES.new(CIPHER_KEY, AES.MODE_CBC, IV)
padded = text + PADDING_CHAR * (16 - len(text) % 16)
encrypted = aes.encrypt(padded)
return b64encode(encrypted)
def decrypt(data):
aes = AES.new(CIPHER_KEY, AES.MODE_CBC, IV)
encrypted = b64decode(data)
padded = aes.decrypt(encrypted)
return padded.rstrip(PADDING_CHAR)
message = "this information is confidential, for your eyes only"
print("secret message: {}".format(message))
encrypted_message = encrypt(message)
print(" encrypted > {}".format(encrypted_message))
decrypted_message = decrypt(encrypted_message)
print(" decrypted > {}".format(decrypted_message))
if message == decrypted_message:
print("SUCCESS")
else:
print("FAILED")
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