day07-java常见加密

1.Java常见加密

1.1 隐藏字节

TreeMap map = new TreeMap();
map.put("sign",x);

# 搜索关键字 sign

String a = new String(new byte[]{-26, -83, -90, -26, -78, -101, -23, -67, -112});
TreeMap map = new TreeMap();
map.put(a,x);
    
# hook机制，找到TreeMap中的put方法，替换成我自己的某个方法。
function newPut(key,value){
    console.log(key,value); 再去获取调用栈。
}

String salt = "xxssasdfasdfadsf";

String v4 = new String(new byte[]{-26, -83, -90, -26, -78, -101, -23, -67, -112});

• 示例1：

  String v1 = new String(new byte[]{26, 83, 90, 26, 78, 101, 23, 67, 112});
  

  # 字节列表
  byte_list = [26, 83, 90, 26, 78, 101, 23, 67, 112]
  
  # 字节列表 -> python的字节数组
  bs = bytearray()
  for item in byte_list:
      bs.append(item)
      
  # python的字节数组 -> 编码 -> 字符串
  str_data = bs.decode('utf-8')
  print(str_data)
  

• 示例2：

  String v4 = new String(new byte[]{-26, -83, -90, -26, -78, -101, -23, -67, -112});
  
  # java字节：有符号 -128 ~ 127
  # python：无符号  0 ~ 255
  

  byte_list = [-26, -83, -90, -26, -78, -101, -23, -67, -112]
  
  bs = bytearray()  # python字节数组
  for item in byte_list:
      if item < 0:
          item = item + 256
      bs.append(item)
  
  str_data = bs.decode('utf-8')  # data = bytes(bs)
  print(str_data)
  

注意事项：什么编码？（utf-8)
	String v4 = new String(new byte[]{-26, -83, -90, -26, -78, -101, -23, -67, -112});

# 类似于Java中的字节数组
data = "张三懵逼了"
data_bytes = data.encode('utf-8')


data_list = bytearray()
for item in data_bytes:
    data_list.append(item)

res = data_list.decode('utf-8')
print(res)

提醒：MD5加密盐、AES加密key、iv;

1.2 uuid

抖音udid

import java.util.UUID;

public class Hello {
    public static void main(String[] args){
        String uid = UUID.randomUUID().toString();
        System.out.println(uid);
    }
}

import uuid

uid = str(uuid.uuid4())
print(uid)

29cd5f50-4b4c-457b-9a59-33a12e3edd10

1.第一类使用uuid
	抓包发现，每次请求值不一样：d7cb3695-5105-4aaa-b0a8-8188e0977143

2.第一次运行生成UUID
	- 刚开始运行：调用uuid算法生成一个值。
	- 写入XML文件
	- 再使用
		- 优先去XML文件中找
		- uuid算法

	此时测试：
		- 清除app数据
		- 必须卸载app，重新安装

1.3 随机值

抖音：openudid

import java.math.BigInteger;
import java.security.SecureRandom;

public class Hello {

    public static void main(String[] args) {
        // 随机生成80位，10个字节
        BigInteger v4 = new BigInteger(80, new SecureRandom());
        // 让字节以16进制展示
        String res = v4.toString(16);
        System.out.println(res);

    }
}

import random

data = random.randbytes(10)  # pytho3.9

ele_list = []
for item in data:
    # 184    十进制  -> 十六进制
    # hex(item)  # 
    ele = hex(item)[2:]
res = "".join(ele_list)
print(res)

data = "".join([ hex(item)[2:] for item in random.randbytes(10)])

import random

data = random.randbytes(10)  # pytho3.9

# b' I\xbf\xf0#\x15}q\x83Q'
print([item for item in data])
print([hex(item)[2:] for item in data])
print([hex(item)[2:].rjust(2, "0") for item in data])
# print("".join([hex(item)[2:] for item in data]))
print("".join([hex(item)[2:].rjust(2, "0") for item in data]))

# 3.9以前

import random
byte_list = [random.randint(0, 255) for i in range(10)]

# b' I\xbf\xf0#\x15}q\x83Q'
print([item for item in byte_list])
print([hex(item)[2:] for item in byte_list])
print([hex(item)[2:].rjust(2, "0") for item in byte_list])
# print("".join([hex(item)[2:] for item in data]))
print("".join([hex(item)[2:].rjust(2, "0") for item in byte_list]))

小补充：十六进制

import random

data = random.randbytes(10)  # pytho3.9

ele_list = []
for item in data:
    ele = hex(item)[2:].rjust(2,"0")
res = "".join(ele_list)
print(res)

data = "".join([ hex(item)[2:].rjust(2,"0") for item in random.randbytes(10)])

转换十六进制字符串：

• 内置函数

  v1 = hex(199)
  
  '0xc7'
  

• 字符串格式化

  v2 = "%x" %(199,)
  
  'c7'
  

  v3 = "%02x" %(5,)
  
  '05'
  

import random

byte_list = [random.randint(0, 255) for i in range(10)]
res = "".join(["%02x" % item for item in byte_list])
print(res)

import random

res = "".join(["%02x" % random.randint(0, 255) for i in range(10)])
print(res)

1.4 时间戳

抖音：_ticket

public class Hello {

    public static void main(String[] args) {
        String t1 = String.valueOf(System.currentTimeMillis() / 1000); // 秒级别
        String t2 = String.valueOf(System.currentTimeMillis()); # 毫秒级别

        System.out.println(t1);
        System.out.println(t2);
    }
}

import time

v1 = int(time.time()) // 秒级别
v2 = int(time.time()*1000) # 毫秒级别

v1 = str(int(time.time()))
v2 = str(int(time.time()*1000))

1.5 十六进制的字符串

在Java中字节是有符号：-128 ~ 127

# name_bytes = "武沛齐".encode('utf-8')
name_bytes = [10, -26, -83, -90, -26, -78, -101, -23, -67, -112]

data_list = []

for item in name_bytes:
    item = item & 0xff   # item<0时，让item+256
    ele = "%02x" % item  # 转为16进制
    data_list.append(ele)
    
print("".join(data_list))

s='pengyuyan'.encode('utf-8')
l=[]
for i in s:
    l.append(hex(i)[2:].rjust(2,'0')) # 转16进制，只去后两位，如果不足两位，补0
print(l)

1.6 md5加密

import hashlib

obj = hashlib.md5()
obj.update('xxxxx'.encode('utf-8'))

# java中没有这个功能。
v1 = obj.hexdigest()
print(v1) # fb0e22c79ac75679e9881e6ba183b354

v2 = obj.digest()
print(v2) # b'\xfb\x0e"\xc7\x9a\xc7Vy\xe9\x88\x1ek\xa1\x83\xb3T'

抖音：X-SS-STUB

每次发送POST请求时，抖音都会携带一些请求头：
	X-SS-STUB = "fjaku9asdf"

读取请求体中的数据，对请求体中的数据进行md5加密。

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;

public class Hello {

    public static void main(String[] args) throws NoSuchAlgorithmException {
        String name = "武沛齐";
        
        MessageDigest instance = MessageDigest.getInstance("MD5");
        byte[] nameBytes = instance.digest(name.getBytes());
       
        // 十六进制展示
        StringBuilder sb = new StringBuilder();
        for(int i=0;i<nameBytes.length;i++){
            int val = nameBytes[i] & 255;  // 负数转换为正数
            if (val<16){
                sb.append("0");
            }
            sb.append(Integer.toHexString(val));
        }
        String hexData = sb.toString();
        System.out.println(hexData); // e6ada6e6b29be9bd90
    }
}

import hashlib

m = hashlib.md5()
m.update("武沛齐".encode("utf-8"))

v1 = m.digest()
print(v1) # b'\x175\x10\x12G$)\xd5-\x0c\r#\xd4h\x17='

v2 = m.hexdigest()
print(v2) # 17351012472429d52d0c0d23d468173d

关于加盐：

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;

public class Hello {

    public static void main(String[] args) throws NoSuchAlgorithmException {
        String name = "武沛齐";
        MessageDigest instance = MessageDigest.getInstance("MD5");
        instance.update("xxxxxx".getBytes());
        
        byte[] nameBytes = instance.digest(name.getBytes());
        
        System.out.println(Arrays.toString(nameBytes));

        String res = new String(nameBytes);
        System.out.println(res);

        // 十六进制展示
        StringBuilder sb = new StringBuilder();
        for(int i=0;i<nameBytes.length;i++){
            int val = nameBytes[i] & 255;  // 负数转换为正数
            if (val<16){
                sb.append("0");
            }
            sb.append(Integer.toHexString(val));
        }
        String hexData = sb.toString();
        System.out.println(hexData); // e6ada6e6b29be9bd90
    }
}

import hashlib

m = hashlib.md5("xxxxxx".encode('utf-8'))
m.update("武沛齐".encode("utf-8"))

v2 = m.hexdigest()
print(v2) # 17351012472429d52d0c0d23d468173d

1.7 sha-256加密

B站：x/report/andriod2，请求体

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;

public class Hello {

    public static void main(String[] args) throws NoSuchAlgorithmException {
        String name = "武沛齐";
        MessageDigest instance = MessageDigest.getInstance("SHA-256");
        byte[] nameBytes = instance.digest(name.getBytes());
        // System.out.println(Arrays.toString(nameBytes));

        // String res = new String(nameBytes);
        // System.out.println(res);

        // 十六进制展示
        StringBuilder sb = new StringBuilder();
        for(int i=0;i<nameBytes.length;i++){
            int val = nameBytes[i] & 255;  // 负数转换为正数
            if (val<16){
                sb.append("0");
            }
            sb.append(Integer.toHexString(val));
        }
        String hexData = sb.toString();
        System.out.println(hexData); // e6ada6e6b29be9bd90
    }
}

import hashlib

m = hashlib.sha256()
m.update("武沛齐".encode("utf-8"))

v2 = m.hexdigest()
print(v2)

1.8 AES加密

对称加密

• key & iv ，明文加密。【app端】
• key & iv ，解密。【API】

情况A: 请求体密文（抓包乱码）
情况B: sign，AES加密+base64编码

刷B站播放时，发送POST请求。

AES加密（请求体中的数据） -> 密文（JS央视频 key & iv & 加密）。

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;

public class Hello {

    public static void main(String[] args) throws Exception {
        String data = "武沛齐";
        String key = "fd6b639dbcff0c2a1b03b389ec763c4b";
        String iv = "77b07a672d57d64c";

        // 加密
        byte[] raw = key.getBytes();
        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
        IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes());
        
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, skeySpec, ivSpec);
        byte[] encrypted = cipher.doFinal(data.getBytes());
        
        // System.out.println(Arrays.toString(encrypted));
        
    }
}

# pip install pycryptodome
from Crypto.Cipher import AES
from Crypto.Util.Padding import pad

KEY = "fd6b639dbcff0c2a1b03b389ec763c4b"
IV = "77b07a672d57d64c"


def aes_encrypt(data_string):
    aes = AES.new(
        key=KEY.encode('utf-8'),
        mode=AES.MODE_CBC,
        iv=IV.encode('utf-8')
    )
    raw = pad(data_string.encode('utf-8'), 16)
    return aes.encrypt(raw)

data = aes_encrypt("武沛齐")
print(data)
print([ i for i in data])

1.9 gzip压缩

抖音注册设备：设备。

注册设备：生成一些值，值中包括： （cdid、手机型号、手机品牌....） 后端读取到时候，发现cdid是一个全新的请求。那么抖音就会生成 device_id、install_id、tt

（cdid、手机型号、手机品牌....） --> gzip压缩(字节)  --> 加密   -->   密文

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.math.BigInteger;
import java.security.SecureRandom;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.io.OutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class Hello {

    public static void main(String[] args) throws IOException {

        // 压缩
        String data = "武沛齐";
        // System.out.println(Arrays.toString(data.getBytes()));
        ByteArrayOutputStream v0_1 = new ByteArrayOutputStream();
        GZIPOutputStream v1 = new GZIPOutputStream((v0_1));
        v1.write(data.getBytes());
        v1.close();
        
        // [11,22,31,14,45]
        byte[] arg6 = v0_1.toByteArray();  //gzip压缩后：arg6
        // System.out.println(Arrays.toString(arg6));

        // 解压缩
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        ByteArrayInputStream in = new ByteArrayInputStream(arg6);
        GZIPInputStream ungzip = new GZIPInputStream(in);
        byte[] buffer = new byte[256];
        int n;
        while ((n = ungzip.read(buffer)) >= 0) {
            out.write(buffer, 0, n);
        }
        byte[] res = out.toByteArray();
        // System.out.println(Arrays.toString(res));
        System.out.println(out.toString("UTF-8"));

    }
}

import gzip


# 压缩
"""
s_in = "我是武沛齐".encode('utf-8')
s_out = gzip.compress(s_in)

print([i for i in s_out])
"""

# 解压缩
"""
res = gzip.decompress(s_out)
print(res)
print(res.decode('utf-8'))
"""

提醒：java、Python语言区别。（个人字节是不同，不影响整个的结果），。

1.10 base64编码

import java.util.Base64;

public class Hello {

    public static void main(String[] args) {
        String name = "武沛齐";
        // 加密
        Base64.Encoder encoder  = Base64.getEncoder();
        String res = encoder.encodeToString(name.getBytes());  // name.getBytes()相当于python中encode('utf-8')
        System.out.println(res); // "5q2m5rKb6b2Q"
		
        // 解密
        Base64.Decoder decoder  = Base64.getDecoder();
        byte[] origin = decoder.decode(res);
        String data = new String(origin);
        System.out.println(data); // 武沛齐

    }
}

import base64

name = "武沛齐"

res = base64.b64encode(name.encode('utf-8'))
print(res) # b'5q2m5rKb6b2Q'


data = base64.b64decode(res)
origin = data.decode('utf-8')
print(origin) # "武沛齐"

# 不同，换行符 + ==