discuz 经典php加密解密函数 authcode
Eave
2015.10.19 13:00
康盛的 authcode 函数可以说对中国的PHP界作出了重大贡献。包括康盛自己的产品，以及大部分中国使用PHP的公司都用这个函数进行加密，authcode 是使用异或运算进行加密和解密。
package com.conline.util;
import java.util.Calendar;
import java.util.Random;
public class AuthCode
{
private static final String AUTHKEY = "CAYU-DLOFU-IFENG-VENE";
public enum authcodeMode
{
Encode, Decode
};
/**
* 字符串加密
* @param source
* @return
*/
public static String encode(String source)
{
return authcode(source, AUTHKEY, authcodeMode.Encode, 0);
}
/**
* 字符串加密
* @param source 原始字符串
* @param key 密钥
* @return
*/
public static String encode(String source, String key)
{
return authcode(source, key, authcodeMode.Encode, 0);
}
/**
* 字符串加密
* @param source 原始字符串
* @param key 密钥
* @param expiry
* @return
*/
public static String encode(String source, String key, int expiry)
{
return authcode(source, key, authcodeMode.Encode, expiry);
}
/**
* 字符串解密
* @param source
* @return
*/
public static String decode(String source)
{
return authcode(source, AUTHKEY, authcodeMode.Decode, 0);
}
/**
* 字符串解密
* @param source 原始字符串
* @param key 密钥
* @return
*/
public static String decode(String source, String key)
{
return authcode(source, key, authcodeMode.Decode, 0);
}
/**
* 使用 变形的 rc4 编码方法对字符串进行加密或者解密
* @param source 原始字符串
* @param key 密钥
* @param operation 操作 加密还是解密
* @param expiry 加密字串过期时间
* @return
*/
private static String authcode(String source, String key, authcodeMode operation, int expiry)
{
String codeString = null;
try
{
if(source != null && key != null)
{
int cKeyLength = 4;
String keya, keyb, keyc, cryptkey, result;
key = Security.md5(key);
keya = Security.md5(cutString(key, 0, 16));
keyb = Security.md5(cutString(key, 16, 16));
keyc = cKeyLength > 0 ? (operation == authcodeMode.Decode ? cutString(source, 0, cKeyLength) : randomString(cKeyLength)) : "";
cryptkey = keya + Security.md5(keya + keyc);
if (operation == authcodeMode.Decode)
{
byte[] temp;
temp = Base64.decode(cutString(source, cKeyLength));
result = new String(RC4(temp, cryptkey));
if (cutString(result, 10, 16).equals(cutString(Security.md5(cutString(result, 26) + keyb), 0, 16)))
{
codeString = cutString(result, 26);
}
else
{
temp = Base64.decode(cutString(source + "=", cKeyLength));
result = new String(RC4(temp, cryptkey));
if (cutString(result, 10, 16).equals(cutString(Security.md5(cutString(result, 26) + keyb), 0, 16)))
{
codeString = cutString(result, 26);
}
else
{
temp = Base64.decode(cutString(source + "==", cKeyLength));
result = new String(RC4(temp, cryptkey));
if (cutString(result, 10, 16).equals(cutString(Security.md5(cutString(result, 26) + keyb), 0, 16)))
{
codeString = cutString(result, 26);
}
}
}
}
else
{
source = "0000000000" + cutString(Security.md5(source + keyb), 0, 16) + source;
byte[] temp = RC4(source.getBytes("UTF-8"), cryptkey);
codeString = keyc + Base64.encodeBytes(temp);
}
}
}
catch (Exception e)
{
System.err.println(e);
}
return codeString;
}
/**
* 字符串截取
* @param str
* @param startIndex
* @param length
* @return
*/
public static String cutString(String str, int startIndex, int length)
{
if(startIndex >= 0)
{
if (length < 0)
{
length = length * -1;
if(startIndex - length < 0)
{
length = startIndex;
startIndex = 0;
}
else
{
startIndex = startIndex - length;
}
}
if(startIndex > str.length())
{
return "";
}
}
else
{
if(length < 0)
{
return "";
}
else
{
if(length + startIndex > 0)
{
length = length + startIndex;
startIndex = 0;
}
else
{
return "";
}
}
}
if (str.length() - startIndex < length)
{
length = str.length() - startIndex;
}
return str.substring(startIndex, startIndex + length);
}
/**
* 字符串截取
* @param str
* @param startIndex
* @return
*/
public static String cutString(String str, int startIndex)
{
return cutString(str, startIndex, str.length());
}
/**
* 用于 RC4 处理密码
* @param pass 密码字串
* @param kLen 密钥长度，一般为 256
* @return
*/
static private byte[] getKey(byte[] pass, int kLen)
{
byte[] mBox = new byte[kLen];
for (int i = 0; i < kLen; i++)
{
mBox[i] = (byte) i;
}
int j = 0;
for (int i = 0; i < kLen; i++)
{
j = (j + (int) ((mBox[i] + 256) % 256) + pass[i % pass.length]) % kLen;
byte temp = mBox[i];
mBox[i] = mBox[j];
mBox[j] = temp;
}
return mBox;
}
/**
* 生成随机字符
* @param lens 随机字符长度
* @return
*/
public static String randomString(int lens)
{
char[] CharArray = {\'a\', \'b\', \'c\', \'d\', \'e\', \'f\', \'g\', \'h\', \'j\', \'k\', \'l\', \'m\', \'n\', \'o\', \'p\', \'q\', \'r\', \'s\', \'t\', \'u\', \'v\', \'w\', \'x\', \'y\', \'z\', \'0\', \'1\', \'2\', \'3\', \'4\', \'5\', \'6\', \'7\', \'8\', \'9\'};
int clens = CharArray.length;
String sCode = "";
Random random = new Random();
for(int i = 0; i < lens; i++)
{
sCode += CharArray[Math.abs(random.nextInt(clens))];
}
return sCode;
}
/**
* RC4 原始算法
* @param input 原始字串数组
* @param pass 密钥
* @return
*/
private static byte[] RC4(byte[] input, String pass)
{
if(input == null || pass == null)
{
return null;
}
byte[] output = new byte[input.length];
byte[] mBox = getKey(pass.getBytes(), 256);
// 加密
int i = 0;
int j = 0;
for(int offset = 0; offset < input.length; offset++)
{
i = (i + 1) % mBox.length;
j = (j + (int) ((mBox[i] + 256) % 256)) % mBox.length;
byte temp = mBox[i];
mBox[i] = mBox[j];
mBox[j] = temp;
byte a = input[offset];
// mBox[j] 一定比 mBox.Length 小，不需要在取模
byte b = mBox[(toInt(mBox[i]) + toInt(mBox[j])) % mBox.length];
output[offset] = (byte) ((int) a ^ (int) toInt(b));
}
return output;
}
public static int toInt(byte b)
{
return (int) ((b + 256) % 256);
}
public long getUnixTimestamp()
{
Calendar cal = Calendar.getInstance();
return cal.getTimeInMillis() / 1000;
}
}