- 算法特点
a) 消息摘要算法/单向散列函数/哈希函数
b) 不同长度的输入，产生固定长度的输出
c) 散列后的密文不可逆
d) 散列后的结果唯一
e) 哈希碰撞
f) 一般用于校验数据完整性、签名sign
由于密文不可逆，所以服务端也无法解密
想要验证，就需要跟前端一样的方式去重新签名一遍
签名算法一般会把源数据和签名后的值一起提交到服务端
要保证在签名时候的数据和提交上去的源数据一致
- 常见算法
MD5、SHA1、SHA256、SHA512、HmacMD5、HmacSHA1、HmacSHA256、HmacSHA512
RIPEMD160、HmacRIPEMD160、PBKDF2、EvpKDF
MD5
MD5的java实现
MessageDigest md5 = MessageDigest.getInstance("MD5");
md5.update("xiaojianbang".getBytes());
md5.digest();
加密后的字节数组可以编码成Hex、Base64
没有任何输入，也能计算hash值
碰到加salt的MD5，可以直接输入空的值，得到结果去CMD5查询一下，有可能就得到salt
SHA
MessageDigest sha1 = MessageDigest.getInstance("SHA-1");
sha1.update("xiaojianbang".getBytes());
sha1.digest();
加密后的字节数组可以编码成Hex、Base64
没有任何输入，也能计算hash值
算法通杀脚本开发
工具函数封装
Java.perform(function () {function showStacks() {console.log(Java.use("android.util.Log").getStackTraceString(Java.use("java.lang.Throwable").$new()));}var ByteString = Java.use("com.android.okhttp.okio.ByteString");function toBase64(data) {console.log(ByteString.of(data).base64());}function toHex(data) {console.log(ByteString.of(data).hex());}function toUtf8(data) {console.log(ByteString.of(data).utf8());}// toBase64([48,49,50,51,52]);// toHex([48,49,50,51,52]);// toUtf8([48,49,50,51,52]);//console.log(Java.enumerateLoadedClassesSync().join("\n"));});MD5算法通杀hook SHA算法通杀hook
Java.perform(function () {function showStacks() {console.log(Java.use("android.util.Log").getStackTraceString(Java.use("java.lang.Throwable").$new()));}var ByteString = Java.use("com.android.okhttp.okio.ByteString");function toBase64(tag, data) {console.log(tag + " Base64: " + ByteString.of(data).base64());}function toHex(tag, data) {console.log(tag + " Hex: " + ByteString.of(data).hex());}function toUtf8(tag, data) {console.log(tag + " Utf8: " + ByteString.of(data).utf8());}var messageDigest = Java.use("java.security.MessageDigest");messageDigest.update.overload('byte').implementation = function (data) {console.log("MessageDigest.update('byte') is called!");showStacks();return this.update(data);}messageDigest.update.overload('java.nio.ByteBuffer').implementation = function (data) {console.log("MessageDigest.update('java.nio.ByteBuffer') is called!");showStacks();return this.update(data);}messageDigest.update.overload('[B').implementation = function (data) {console.log("MessageDigest.update('[B') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " update data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);console.log("=======================================================");return this.update(data);}messageDigest.update.overload('[B', 'int', 'int').implementation = function (data, start, length) {console.log("MessageDigest.update('[B', 'int', 'int') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " update data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);console.log("=======================================================", start, length);return this.update(data, start, length);}messageDigest.digest.overload().implementation = function () {console.log("MessageDigest.digest() is called!");showStacks();var result = this.digest();var algorithm = this.getAlgorithm();var tag = algorithm + " digest result";toUtf8(tag, result);toHex(tag, result);toBase64(tag, result);console.log("=======================================================");return result;}messageDigest.digest.overload('[B').implementation = function (data) {console.log("MessageDigest.digest('[B') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " digest data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);var result = this.digest(data);var tags = algorithm + " digest result";toUtf8(tag, result);toHex(tags, result);toBase64(tags, result);console.log("=======================================================");return result;}messageDigest.digest.overload('[B', 'int', 'int').implementation = function (data, start, length) {console.log("MessageDigest.digest('[B', 'int', 'int') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " digest data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);var result = this.digest(data, start, length);var tags = algorithm + " digest result";toHex(tags, result);toBase64(tags, result);console.log("=======================================================", start, length);return result;}
});MAC
MAC算法与MD和SHA的区别是多了一个密钥，密钥可以随机给
MAC的Java实现
SecretKeySpec secretKeySpec = new SecretKeySpec("a12345678".getBytes(),"HmacSHA1");
Mac mac = Mac.getInstance(secretKeySpec.getAlgorithm());
mac.init(secretKeySpec);
mac.update("xxxa".getBytes());
mac.doFinal();
加密后的字节数组可以编码成Hex、Base64
没有任何输入，也能计算hash值
Java.perform(function () {function showStacks() {console.log(Java.use("android.util.Log").getStackTraceString(Java.use("java.lang.Throwable").$new()));}var ByteString = Java.use("com.android.okhttp.okio.ByteString");function toBase64(tag, data) {console.log(tag + " Base64: " + ByteString.of(data).base64());}function toHex(tag, data) {console.log(tag + " Hex: " + ByteString.of(data).hex());}function toUtf8(tag, data) {console.log(tag + " Utf8: " + ByteString.of(data).utf8());}// toUtf8("xx",[48, 49, 50, 51, 52]);// toBase64("xx",[48, 49, 50, 51, 52]);// toHex("xx",[48, 49, 50, 51, 52]);var messageDigest = Java.use("java.security.MessageDigest");messageDigest.update.overload('byte').implementation = function (data) {console.log("MessageDigest.update('byte') is called!");showStacks();return this.update(data);}messageDigest.update.overload('java.nio.ByteBuffer').implementation = function (data) {console.log("MessageDigest.update('java.nio.ByteBuffer') is called!");showStacks();return this.update(data);}messageDigest.update.overload('[B').implementation = function (data) {console.log("MessageDigest.update('[B') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " update data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);console.log("=======================================================");return this.update(data);}messageDigest.update.overload('[B', 'int', 'int').implementation = function (data, start, length) {console.log("MessageDigest.update('[B', 'int', 'int') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " update data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);console.log("=======================================================", start, length);return this.update(data, start, length);}messageDigest.digest.overload().implementation = function () {console.log("MessageDigest.digest() is called!");showStacks();var result = this.digest();var algorithm = this.getAlgorithm();var tag = algorithm + " digest result";toUtf8(tag, result);toHex(tag, result);toBase64(tag, result);console.log("=======================================================");return result;}messageDigest.digest.overload('[B').implementation = function (data) {console.log("MessageDigest.digest('[B') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " digest data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);var result = this.digest(data);var tags = algorithm + " digest result";toUtf8(tag, result);toHex(tags, result);toBase64(tags, result);console.log("=======================================================");return result;}messageDigest.digest.overload('[B', 'int', 'int').implementation = function (data, start, length) {console.log("MessageDigest.digest('[B', 'int', 'int') is called!");showStacks();var algorithm = this.getAlgorithm();var tag = algorithm + " digest data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);var result = this.digest(data, start, length);var tags = algorithm + " digest result";toHex(tags, result);toBase64(tags, result);console.log("=======================================================", start, length);return result;}var mac = Java.use("javax.crypto.Mac");mac.init.overload('java.security.Key', 'java.security.spec.AlgorithmParameterSpec').implementation = function (key, AlgorithmParameterSpec) {console.log("Mac.init('java.security.Key', 'java.security.spec.AlgorithmParameterSpec') is called!");return this.init(key, AlgorithmParameterSpec);}mac.init.overload('java.security.Key').implementation = function (key) {console.log("Mac.init('java.security.Key') is called!");var algorithm = this.getAlgorithm();var tag = algorithm + " init Key";var keyBytes = key.getEncoded();toUtf8(tag, keyBytes);toHex(tag, keyBytes);toBase64(tag, keyBytes);console.log("=======================================================");return this.init(key);}mac.update.overload('byte').implementation = function (data) {console.log("Mac.update('byte') is called!");return this.update(data);}mac.update.overload('java.nio.ByteBuffer').implementation = function (data) {console.log("Mac.update('java.nio.ByteBuffer') is called!");return this.update(data);}mac.update.overload('[B').implementation = function (data) {console.log("Mac.update('[B') is called!");var algorithm = this.getAlgorithm();var tag = algorithm + " update data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);console.log("=======================================================");return this.update(data);}mac.update.overload('[B', 'int', 'int').implementation = function (data, start, length) {console.log("Mac.update('[B', 'int', 'int') is called!");var algorithm = this.getAlgorithm();var tag = algorithm + " update data";toUtf8(tag, data);toHex(tag, data);toBase64(tag, data);console.log("=======================================================", start, length);return this.update(data, start, length);}mac.doFinal.overload().implementation = function () {console.log("Mac.doFinal() is called!");var result = this.doFinal();var algorithm = this.getAlgorithm();var tag = algorithm + " doFinal result";toUtf8(tag, result);toHex(tag, result);toBase64(tag, result);console.log("=======================================================");return result;}mac.doFinal.overload('[B').implementation = function (data) {console.log("Mac.doFinal.overload('[B') is called!");return this.doFinal(data);}mac.doFinal.overload('[B', 'int').implementation = function (output, outOffset) {console.log("Mac.doFinal.overload('[B', 'int') is called!");return this.doFinal(output, outOffset);}});
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