com.haoxuer.discover.user.utils.Digests Maven / Gradle / Ivy
package com.haoxuer.discover.user.utils;
import java.io.IOException;
import java.io.InputStream;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.security.SecureRandom;
import org.apache.commons.lang3.Validate;
/**
* 支持SHA-1/MD5消息摘要的工具类.
*
* 返回ByteSource，可进一步被编码为Hex, Base64或UrlSafeBase64
*
* @author calvin
*/
public class Digests {
private static final String SHA1 = "SHA-1";
private static final String MD5 = "MD5";
private static SecureRandom random = new SecureRandom();
/**
* 对输入字符串进行sha1散列.
*/
public static byte[] sha1(byte[] input) {
return digest(input, SHA1, null, 1);
}
public static byte[] sha1(byte[] input, byte[] salt) {
return digest(input, SHA1, salt, 1);
}
public static byte[] sha1(byte[] input, byte[] salt, int iterations) {
return digest(input, SHA1, salt, iterations);
}
/**
* 对字符串进行散列, 支持md5与sha1算法.
*/
private static byte[] digest(byte[] input, String algorithm, byte[] salt, int iterations) {
try {
MessageDigest digest = MessageDigest.getInstance(algorithm);
if (salt != null) {
digest.update(salt);
}
byte[] result = digest.digest(input);
for (int i = 1; i < iterations; i++) {
digest.reset();
result = digest.digest(result);
}
return result;
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}
/**
* 生成随机的Byte[]作为salt.
*
* @param numBytes byte数组的大小
*/
public static byte[] generateSalt(int numBytes) {
Validate.isTrue(numBytes > 0, "numBytes argument must be a positive integer (1 or larger)", numBytes);
byte[] bytes = new byte[numBytes];
random.nextBytes(bytes);
return bytes;
}
/**
* 对文件进行md5散列.
*/
public static byte[] md5(InputStream input) throws IOException {
return digest(input, MD5);
}
/**
* 对文件进行sha1散列.
*/
public static byte[] sha1(InputStream input) throws IOException {
return digest(input, SHA1);
}
private static byte[] digest(InputStream input, String algorithm) throws IOException {
try {
MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
int bufferLength = 8 * 1024;
byte[] buffer = new byte[bufferLength];
int read = input.read(buffer, 0, bufferLength);
while (read > -1) {
messageDigest.update(buffer, 0, read);
read = input.read(buffer, 0, bufferLength);
}
return messageDigest.digest();
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}
}