package yalp.libs;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import org.apache.commons.codec.binary.Base64;
import javax.crypto.Cipher;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import yalp.Yalp;
import yalp.exceptions.UnexpectedException;
/**
* Cryptography utils
*/
public class Crypto {
/**
* Define a hash type enumeration for strong-typing
*/
public enum HashType {
MD5("MD5"),
SHA1("SHA-1"),
SHA256("SHA-256"),
SHA512("SHA-512");
private String algorithm;
HashType(String algorithm) {
this.algorithm = algorithm;
}
@Override
public String toString() {
return this.algorithm;
}
}
/**
* Set-up MD5 as the default hashing algorithm
*/
private static final HashType DEFAULT_HASH_TYPE = HashType.MD5;
static final char[] HEX_CHARS = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
/**
* Sign a message using the application secret key (HMAC-SHA1)
*/
public static String sign(String message) {
return sign(message, Yalp.secretKey.getBytes());
}
/**
* Sign a message with a key
*
* @param message The message to sign
* @param key The key to use
* @return The signed message (in hexadecimal)
* @throws java.lang.Exception
*/
public static String sign(String message, byte[] key) {
if (key.length == 0) {
return message;
}
try {
Mac mac = Mac.getInstance("HmacSHA1");
SecretKeySpec signingKey = new SecretKeySpec(key, "HmacSHA1");
mac.init(signingKey);
byte[] messageBytes = message.getBytes("utf-8");
byte[] result = mac.doFinal(messageBytes);
int len = result.length;
char[] hexChars = new char[len * 2];
for (int charIndex = 0, startIndex = 0; charIndex < hexChars.length; ) {
int bite = result[startIndex++] & 0xff;
hexChars[charIndex++] = HEX_CHARS[bite >> 4];
hexChars[charIndex++] = HEX_CHARS[bite & 0xf];
}
return new String(hexChars);
} catch (Exception ex) {
throw new UnexpectedException(ex);
}
}
/**
* Create a password hash using the default hashing algorithm
*
* @param input The password
* @return The password hash
*/
public static String passwordHash(String input) {
return passwordHash(input, DEFAULT_HASH_TYPE);
}
/**
* Create a password hash using specific hashing algorithm
*
* @param input The password
* @param hashType The hashing algorithm
* @return The password hash
*/
public static String passwordHash(String input, HashType hashType) {
try {
MessageDigest m = MessageDigest.getInstance(hashType.toString());
byte[] out = m.digest(input.getBytes());
return new String(Base64.encodeBase64(out));
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException(e);
}
}
/**
* Encrypt a String with the AES encryption standard using the application secret
*
* @param value The String to encrypt
* @return An hexadecimal encrypted string
*/
public static String encryptAES(String value) {
return encryptAES(value, Yalp.configuration.getProperty("application.secret").substring(0, 16));
}
/**
* Encrypt a String with the AES encryption standard. Private key must have a length of 16 bytes
*
* @param value The String to encrypt
* @param privateKey The key used to encrypt
* @return An hexadecimal encrypted string
*/
public static String encryptAES(String value, String privateKey) {
try {
byte[] raw = privateKey.getBytes();
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
return Codec.byteToHexString(cipher.doFinal(value.getBytes()));
} catch (Exception ex) {
throw new UnexpectedException(ex);
}
}
/**
* Decrypt a String with the AES encryption standard using the application secret
*
* @param value An hexadecimal encrypted string
* @return The decrypted String
*/
public static String decryptAES(String value) {
return decryptAES(value, Yalp.configuration.getProperty("application.secret").substring(0, 16));
}
/**
* Decrypt a String with the AES encryption standard. Private key must have a length of 16 bytes
*
* @param value An hexadecimal encrypted string
* @param privateKey The key used to encrypt
* @return The decrypted String
*/
public static String decryptAES(String value, String privateKey) {
try {
byte[] raw = privateKey.getBytes();
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
return new String(cipher.doFinal(Codec.hexStringToByte(value)));
} catch (Exception ex) {
throw new UnexpectedException(ex);
}
}
}