Java 从 CryptoJS 解密
Java decryption from CryptoJS
我正在尝试解密 Java-size 一些以前在 CryptoJS (angualrjs) 中加密的信息。
以下是一些代码片段：
加密在Angularjs
CryptoJS.AES.encrypt(message, "my secret key").toString();
解密在Java
package com.mypackage;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
public class AES {
private static SecretKeySpec secretKey;
private static byte[] key;
public static void setKey(String myKey) {
MessageDigest sha = null;
try {
key = myKey.getBytes("UTF-8");
sha = MessageDigest.getInstance("SHA-1");
key = sha.digest(key);
key = Arrays.copyOf(key, 16);
secretKey = new SecretKeySpec(key, "AES");
}
catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
public static String decrypt(String strToDecrypt, String secret) {
try{
setKey(secret);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, AES.secretKey);
return new String(cipher.doFinal(Base64.getDecoder().decode(strToDecrypt)));
} catch (Exception e) {
System.out.println("Error while decrypting: " + e.toString());
}
return null;
}
}
调用java解密方法
@PostMapping("/decryption")
public ResponseEntity<DecryptResponseBean> decryption(@RequestBody DecryptRequestBean data){
String dataToDecrypt = data.getData();
String decrypted = AES.decrypt(dataToDecrypt, "my secret key");
DecryptResponseBean responseBean = new DecryptResponseBean(decrypted);
return ResponseEntity.ok(responseBean);
}
我得到以下异常：
java.security.InvalidKeyException: 缺少参数
我做错了什么？
EDIT1 异常的完整堆栈跟踪
java.security.InvalidKeyException: Parameters missing
at com.sun.crypto.provider.CipherCore.init(CipherCore.java:469)
at com.sun.crypto.provider.AESCipher.engineInit(AESCipher.java:313)
at javax.crypto.Cipher.implInit(Cipher.java:805)
at javax.crypto.Cipher.chooseProvider(Cipher.java:867)
at javax.crypto.Cipher.init(Cipher.java:1252)
at javax.crypto.Cipher.init(Cipher.java:1189)
at com.ses.aes.AES.decrypt(AES.java:53)
at com.ses.services.Encryption.decryption(Encryption.java:34)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:892)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1039)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:853)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1587)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Error while decrypting: java.security.InvalidKeyException: Parameters missing
EDIT2：样本数据集
Key: 1234567890123456 (Both Angular and Java side)
Clear data: this is my text
Chipered data in CryptoJS: U2FsdGVkX18C7J5wy5R5FRjfP5Xghpry3FtuTj5xq+o=
What Java backend receives: U2FsdGVkX18C7J5wy5R5FRjfP5Xghpry3FtuTj5xq+o=
在 Whosebug 上稍微搜索一下，您可能会找到与此处相同的解决方案。重要的代码不是我自己的，而是来自作者@Codo 的答案，所以所有的功劳都归于他。
Crypto.JS 从密码短语（“key”）导出密钥和初始化向量 (iv)，因此方法 GenerateKeyAndIV 负责获取密钥和 IV。
以下代码没有正确的异常处理，仅供参考。
结果：
Java decryption from CryptoJS
decrypted text: this is my text
expected data: this is my text
代码：
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.nio.charset.StandardCharsets;
import java.security.*;
import java.util.Arrays;
import java.util.Base64;
public class Main {
public static void main(String[] args) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidAlgorithmParameterException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
System.out.println("
System.out.println("Java decryption from CryptoJS");
String secret = "1234567890123456";
String cipherText = "U2FsdGVkX18C7J5wy5R5FRjfP5Xghpry3FtuTj5xq+o=";
String expectedData = "this is my text";
// decode base64 encoding
byte[] ciphertextData = Base64.getDecoder().decode(cipherText);
byte[] saltData = Arrays.copyOfRange(ciphertextData, 8, 16);
// generate key & iv
MessageDigest md5 = MessageDigest.getInstance("MD5");
final byte[][] keyAndIV = GenerateKeyAndIV(32, 16, 1, saltData, secret.getBytes(StandardCharsets.UTF_8), md5);
SecretKeySpec key = new SecretKeySpec(keyAndIV[0], "AES");
IvParameterSpec iv = new IvParameterSpec(keyAndIV[1]);
// get encrypted data without iv
byte[] encrypted = Arrays.copyOfRange(ciphertextData, 16, ciphertextData.length);
Cipher aesCBC = Cipher.getInstance("AES/CBC/PKCS5Padding");
aesCBC.init(Cipher.DECRYPT_MODE, key, iv);
// decryption
byte[] decryptedData = aesCBC.doFinal(encrypted);
String decryptedText = new String(decryptedData, StandardCharsets.UTF_8);
System.out.println("decrypted text: " + decryptedText);
System.out.println("expected data: " + expectedData);
}
/**
* Generates a key and an initialization vector (IV) with the given salt and password.
* <p>
* This method is equivalent to OpenSSL's EVP_BytesToKey function
* (see https://github.com/openssl/openssl/blob/master/crypto/evp/evp_key.c).
* By default, OpenSSL uses a single iteration, MD5 as the algorithm and UTF-8 encoded password data.
* </p>
* @param keyLength the length of the generated key (in bytes)
* @param ivLength the length of the generated IV (in bytes)
* @param iterations the number of digestion rounds
* @param salt the salt data (8 bytes of data or <code>null</code>)
* @param password the password data (optional)
* @param md the message digest algorithm to use
* @return an two-element array with the generated key and IV
* answered Jan 2 '17 at 23:38 author Codo
*
*/
public static byte[][] GenerateKeyAndIV(int keyLength, int ivLength, int iterations, byte[] salt, byte[] password, MessageDigest md) {
int digestLength = md.getDigestLength();
int requiredLength = (keyLength + ivLength + digestLength - 1) / digestLength * digestLength;
byte[] generatedData = new byte[requiredLength];
int generatedLength = 0;
try {
md.reset();
// Repeat process until sufficient data has been generated
while (generatedLength < keyLength + ivLength) {
// Digest data (last digest if available, password data, salt if available)
if (generatedLength > 0)
md.update(generatedData, generatedLength - digestLength, digestLength);
md.update(password);
if (salt != null)
md.update(salt, 0, 8);
md.digest(generatedData, generatedLength, digestLength);
// additional rounds
for (int i = 1; i < iterations; i++) {
md.update(generatedData, generatedLength, digestLength);
md.digest(generatedData, generatedLength, digestLength);
}
generatedLength += digestLength;
}
// Copy key and IV into separate byte arrays
byte[][] result = new byte[2][];
result[0] = Arrays.copyOfRange(generatedData, 0, keyLength);
if (ivLength > 0)
result[1] = Arrays.copyOfRange(generatedData, keyLength, keyLength + ivLength);
return result;
} catch (DigestException e) {
throw new RuntimeException(e);
} finally {
// Clean out temporary data
Arrays.fill(generatedData, (byte)0);
}
}
}
我正在尝试解密 Java-size 一些以前在 CryptoJS (angualrjs) 中加密的信息。 以下是一些代码片段：
加密在Angularjs
CryptoJS.AES.encrypt(message, "my secret key").toString();
解密在Java
package com.mypackage;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
public class AES {
private static SecretKeySpec secretKey;
private static byte[] key;
public static void setKey(String myKey) {
MessageDigest sha = null;
try {
key = myKey.getBytes("UTF-8");
sha = MessageDigest.getInstance("SHA-1");
key = sha.digest(key);
key = Arrays.copyOf(key, 16);
secretKey = new SecretKeySpec(key, "AES");
}
catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
public static String decrypt(String strToDecrypt, String secret) {
try{
setKey(secret);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, AES.secretKey);
return new String(cipher.doFinal(Base64.getDecoder().decode(strToDecrypt)));
} catch (Exception e) {
System.out.println("Error while decrypting: " + e.toString());
}
return null;
}
}
调用java解密方法
@PostMapping("/decryption")
public ResponseEntity<DecryptResponseBean> decryption(@RequestBody DecryptRequestBean data){
String dataToDecrypt = data.getData();
String decrypted = AES.decrypt(dataToDecrypt, "my secret key");
DecryptResponseBean responseBean = new DecryptResponseBean(decrypted);
return ResponseEntity.ok(responseBean);
}
我得到以下异常：
java.security.InvalidKeyException: 缺少参数
我做错了什么？
EDIT1 异常的完整堆栈跟踪
java.security.InvalidKeyException: Parameters missing
at com.sun.crypto.provider.CipherCore.init(CipherCore.java:469)
at com.sun.crypto.provider.AESCipher.engineInit(AESCipher.java:313)
at javax.crypto.Cipher.implInit(Cipher.java:805)
at javax.crypto.Cipher.chooseProvider(Cipher.java:867)
at javax.crypto.Cipher.init(Cipher.java:1252)
at javax.crypto.Cipher.init(Cipher.java:1189)
at com.ses.aes.AES.decrypt(AES.java:53)
at com.ses.services.Encryption.decryption(Encryption.java:34)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:892)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1039)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:109)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:853)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1587)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Error while decrypting: java.security.InvalidKeyException: Parameters missing
EDIT2：样本数据集
Key: 1234567890123456 (Both Angular and Java side)
Clear data: this is my text
Chipered data in CryptoJS: U2FsdGVkX18C7J5wy5R5FRjfP5Xghpry3FtuTj5xq+o=
What Java backend receives: U2FsdGVkX18C7J5wy5R5FRjfP5Xghpry3FtuTj5xq+o=
在 Whosebug 上稍微搜索一下，您可能会找到与此处相同的解决方案。重要的代码不是我自己的，而是来自作者@Codo 的答案
Crypto.JS 从密码短语（“key”）导出密钥和初始化向量 (iv)，因此方法 GenerateKeyAndIV 负责获取密钥和 IV。
以下代码没有正确的异常处理，仅供参考。
结果：
Java decryption from CryptoJS
decrypted text: this is my text
expected data: this is my text
代码：
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.nio.charset.StandardCharsets;
import java.security.*;
import java.util.Arrays;
import java.util.Base64;
public class Main {
public static void main(String[] args) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidAlgorithmParameterException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
System.out.println("
System.out.println("Java decryption from CryptoJS");
String secret = "1234567890123456";
String cipherText = "U2FsdGVkX18C7J5wy5R5FRjfP5Xghpry3FtuTj5xq+o=";
String expectedData = "this is my text";
// decode base64 encoding
byte[] ciphertextData = Base64.getDecoder().decode(cipherText);
byte[] saltData = Arrays.copyOfRange(ciphertextData, 8, 16);
// generate key & iv
MessageDigest md5 = MessageDigest.getInstance("MD5");
final byte[][] keyAndIV = GenerateKeyAndIV(32, 16, 1, saltData, secret.getBytes(StandardCharsets.UTF_8), md5);
SecretKeySpec key = new SecretKeySpec(keyAndIV[0], "AES");
IvParameterSpec iv = new IvParameterSpec(keyAndIV[1]);
// get encrypted data without iv
byte[] encrypted = Arrays.copyOfRange(ciphertextData, 16, ciphertextData.length);
Cipher aesCBC = Cipher.getInstance("AES/CBC/PKCS5Padding");
aesCBC.init(Cipher.DECRYPT_MODE, key, iv);
// decryption
byte[] decryptedData = aesCBC.doFinal(encrypted);
String decryptedText = new String(decryptedData, StandardCharsets.UTF_8);
System.out.println("decrypted text: " + decryptedText);
System.out.println("expected data: " + expectedData);
}
/**
* Generates a key and an initialization vector (IV) with the given salt and password.
* <p>
* This method is equivalent to OpenSSL's EVP_BytesToKey function
* (see https://github.com/openssl/openssl/blob/master/crypto/evp/evp_key.c).
* By default, OpenSSL uses a single iteration, MD5 as the algorithm and UTF-8 encoded password data.
* </p>
* @param keyLength the length of the generated key (in bytes)
* @param ivLength the length of the generated IV (in bytes)
* @param iterations the number of digestion rounds
* @param salt the salt data (8 bytes of data or <code>null</code>)
* @param password the password data (optional)
* @param md the message digest algorithm to use
* @return an two-element array with the generated key and IV
* answered Jan 2 '17 at 23:38 author Codo
*
*/
public static byte[][] GenerateKeyAndIV(int keyLength, int ivLength, int iterations, byte[] salt, byte[] password, MessageDigest md) {
int digestLength = md.getDigestLength();
int requiredLength = (keyLength + ivLength + digestLength - 1) / digestLength * digestLength;
byte[] generatedData = new byte[requiredLength];
int generatedLength = 0;
try {
md.reset();
// Repeat process until sufficient data has been generated
while (generatedLength < keyLength + ivLength) {
// Digest data (last digest if available, password data, salt if available)
if (generatedLength > 0)
md.update(generatedData, generatedLength - digestLength, digestLength);
md.update(password);
if (salt != null)
md.update(salt, 0, 8);
md.digest(generatedData, generatedLength, digestLength);
// additional rounds
for (int i = 1; i < iterations; i++) {
md.update(generatedData, generatedLength, digestLength);
md.digest(generatedData, generatedLength, digestLength);
}
generatedLength += digestLength;
}
// Copy key and IV into separate byte arrays
byte[][] result = new byte[2][];
result[0] = Arrays.copyOfRange(generatedData, 0, keyLength);
if (ivLength > 0)
result[1] = Arrays.copyOfRange(generatedData, keyLength, keyLength + ivLength);
return result;
} catch (DigestException e) {
throw new RuntimeException(e);
} finally {
// Clean out temporary data
Arrays.fill(generatedData, (byte)0);
}
}
}