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How to port MD5 signature code from Java to C#

I'm trying to port the following Java code to C#, but so far it still says that the signature is invalid.
private static String generateSignStr(Map<String, String> params, String key) {
StringBuilder sb = new StringBuilder();
params.entrySet().stream().sorted(Map.Entry.comparingByKey()).forEach(entry -> {
if (sb.length() > 0) {
sb.append('&');
}
sb.append(entry.getKey()).append('=');
sb.append(entry.getValue());
});
sb.append('&').append("api_secret")
.append('=').append(key);
return sb.toString();
}
private static String sign(String target) {
MessageDigest md;
try {
md = MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
log.error("Fail to get MD5 instance");
return null;
}
md.update(target.getBytes());
byte[] dg = md.digest();
StringBuilder output = new StringBuilder(dg.length * 2);
for (byte dgByte : dg) {
int current = dgByte & 0xff;
if (current < 16) {
output.append("0");
}
output.append(Integer.toString(current, 16));
}
return output.toString();
}
private static string GenerateSign(Dictionary<string, object> query, string apiSecret)
{
var sb = new StringBuilder();
var queryParameterString = string.Join("&",
query.Where(kvp => !string.IsNullOrWhiteSpace(kvp.Value.ToString()))
.Select(kvp => $"{kvp.Key}={HttpUtility.UrlEncode(kvp.Value.ToString())}"));
sb.Append(queryParameterString);
if (sb.Length > 0)
{
sb.Append('&');
}
sb.Append("api_secret=").Append(apiSecret);
return sb.ToString();
}
private static string Sign(string source)
{
using var md5 = MD5.Create();
var sourceBytes = Encoding.UTF8.GetBytes(source);
var hash = md5.ComputeHash(sourceBytes);
return BitConverter.ToString(hash).Replace("-", string.Empty).ToLowerInvariant();
}
Edit:
This fixed it. However, it would be nice if someone knows a way to lexicographically sort the dictionary inside that method just like the Java code.
var #params = new Dictionary<string, object>
{
{ "api_key", _apiKey },
{ "req_time", now },
{ "op", "sub.personal" }
};
var javaSorted = #params.OrderBy(item => item.Key, StringComparer.Ordinal)
.ToDictionary(i => i.Key, i => i.Value);
var signature = Sign(GenerateSign(javaSorted, _apiSecret));

In GenerateSign method you can just create instance of SortedDictionary based on dictionary passed as parameter:
private static string GenerateSign(Dictionary<string, object> query, string apiSecret)
{
var sortedDict = new SortedDictionary<string, object>(query, StringComparer.Ordinal);
// rest of the method
}
Or you can do even better (note the important change from Dictionary to IDictionary):
private static string GenerateSign(IDictionary<string, object> query, string apiSecret)
{
query = new SortedDictionary<string, object>(query, StringComparer.Ordinal);
// rest of the method
}

SM2Engine can encrypt,but how to add envelop on it?

I can get a public key from a certificate file,and use code below to encrypt a message with sm2engine.
public static String encrypt(String data, PublicKey publicKey)
{
ECPublicKeyParameters localECPublicKeyParameters = null;
if (publicKey instanceof BCECPublicKey)
{
BCECPublicKey localECPublicKey = (BCECPublicKey)publicKey;
ECParameterSpec localECParameterSpec = localECPublicKey.getParameters();
ECDomainParameters localECDomainParameters = new ECDomainParameters(
localECParameterSpec.getCurve(), localECParameterSpec.getG(),
localECParameterSpec.getN());
localECPublicKeyParameters = new ECPublicKeyParameters(localECPublicKey.getQ(),
localECDomainParameters);
}
SM2Engine localSM2Engine = new SM2Engine();
localSM2Engine.init(true, new ParametersWithRandom(localECPublicKeyParameters,
new SecureRandom()));
byte[] arrayOfByte2;
try
{
arrayOfByte2 = localSM2Engine.processBlock(data.getBytes(), 0, data.getBytes().length);
return new String(Base64.encode(arrayOfByte2));
}
catch (InvalidCipherTextException e)
{
e.printStackTrace();
return null;
}
But it is not enveloped,I do not know how to add an envelop on it,but I know how to add envelop without sm2egine:
public static String encryptMessage(String message, X509Certificate cert) throws Exception {
CMSEnvelopedDataGenerator gen = new CMSEnvelopedDataGenerator();
gen.addRecipientInfoGenerator(new JceKeyTransRecipientInfoGenerator(cert));
OutputEncryptor encryptor = new JceCMSContentEncryptorBuilder(CMSAlgorithm.AES128_CBC).setProvider(BouncyCastleProvider.PROVIDER_NAME).build();
CMSTypedData content = new CMSProcessableByteArray(message.getBytes("UTF-8"));
CMSEnvelopedData data = gen.generate(content, encryptor);
String encryptedMessage = new String(Base64.encode(data.getEncoded()));
return encryptedMessage;
}
but now I must use the special algorithm called sm4 as the symmetric algorithm to encrypt the content first,not aes.And then use sm2 to encypt the key of sm4,all as it defined in pkcs7.so how to join these two code fragment?
All special algorithms seem can be implemented by BouncyCastle method,but there is no sm4 in CMSAlgorithm class,but I found a GMObjectIndenrifier.sms4_cbc,and pass it as a parameter,but got a exception:
no such algorithm.
More info:after I parse the certificate from a file, and call certificate.getSigAlgName(),its name is SM3WITHSM2

how to encrypt and decrypt data between php and android

These are my classes used in order to encrypt and decrypt data between a php based server and an android application.
Sometimes the php decrypt class does not work:
For example when I encrypt "abc" or "zdf" or "091360532561524369510" in android, the php class could not decrypt the encrypted data from the android client side.
Can you please check these classes?
java class:
import java.security.NoSuchAlgorithmException;
import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class ApiCrypter
{
private String iv= "0123456789012345";
private String secretkey= "9876543210987654";
private IvParameterSpec ivspec;
private SecretKeySpec keyspec;
private Cipher cipher;
public ApiCrypter()
{
ivspec = new IvParameterSpec(iv.getBytes());
keyspec = new SecretKeySpec(secretkey.getBytes(), "AES");
try {
cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
}
}
public byte[] encrypt(String text) throws Exception
{
if(text == null || text.length() == 0) {
throw new Exception("Empty string");
}
byte[] encrypted = null;
try {
cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
encrypted = cipher.doFinal(text.getBytes("UTF-8"));
}
catch (Exception e) {
throw new Exception("[encrypt] " + e.getMessage());
}
return encrypted;
}
public byte[] decrypt(String code) throws Exception
{
if(code == null || code.length() == 0) {
throw new Exception("Empty string");
}
byte[] decrypted = null;
try {
cipher.init(Cipher.DECRYPT_MODE, keyspec, ivspec);
decrypted = cipher.doFinal(hexToBytes(code));
}
catch (Exception e) {
throw new Exception("[decrypt] " + e.getMessage());
}
return decrypted;
}
public static String bytesToHex(byte[] data)
{
if (data==null) {
return null;
}
int len = data.length;
String str = "";
for (int i=0; i<len; i++) {
if ((data[i]&0xFF)<16) {
str = str + "0" + java.lang.Integer.toHexString(data[i]&0xFF);
}
else {
str = str + java.lang.Integer.toHexString(data[i]&0xFF);
}
}
return str;
}
public static byte[] hexToBytes(String str) {
if (str==null) {
return null;
}
else if (str.length() < 2) {
return null;
}
else {
int len = str.length() / 2;
byte[] buffer = new byte[len];
for (int i=0; i<len; i++) {
buffer[i] = (byte) Integer.parseInt(str.substring(i*2,i*2+2),16);
}
return buffer;
}
}
}
PHP class :
<?php
class ApiCrypter
{
private $iv = '0123456789012345';
private $key = '9876543210987654';
public function __construct()
{
}
public function encrypt($str)
{
$str = $this->pkcs5_pad($str);
$iv = $this->iv;
$td = mcrypt_module_open('rijndael-128', '', 'cbc', $iv);
mcrypt_generic_init($td, $this->key, $iv);
$encrypted = mcrypt_generic($td, $str);
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
return bin2hex($encrypted);
}
public function decrypt($code)
{
$code = $this->hex2bin($code);
$iv = $this->iv;
$td = mcrypt_module_open('rijndael-128', '', 'cbc', $iv);
mcrypt_generic_init($td, $this->key, $iv);
$decrypted = mdecrypt_generic($td, $code);
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
$ut = utf8_encode(trim($decrypted));
return $this->pkcs5_unpad($ut);
}
protected function hex2bin($hexdata)
{
$bindata = '';
for ($i = 0; $i < strlen($hexdata); $i += 2) {
$bindata .= chr(hexdec(substr($hexdata, $i, 2)));
}
return $bindata;
}
protected function pkcs5_pad ($text)
{
$blocksize = 16;
$pad = $blocksize - (strlen($text) % $blocksize);
return $text . str_repeat(chr($pad), $pad);
}
protected function pkcs5_unpad($text)
{
$pad = ord($text{strlen($text)-1});
if ($pad > strlen($text))
{
return false;
}
if (strspn($text, chr($pad), strlen($text) - $pad) != $pad)
{
return false;
}
return substr($text, 0, -1 * $pad);
}
}
?>

A couple of things:
Your IVs should be distinct per message and unpredictable; never hard-coded.
Don't use mcrypt in PHP.
This is the easiest way to solve your problem:
Get libsodium in both languages. If you upgrade your PHP to 7.2 or newer, you should get the Sodium extension automatically (unless your OS vendor is doing something wrong).
Use crypto_secretbox() (or the equivalent API in your language) to encrypt, crypto_secretbox_open() to decrypt.
This is simpler than learning the proper way to fuss about with CBC mode, Initialization Vectors, padding schemes, RNGs, and ciphertext integrity.

java.security.InvalidKeyException: unknown key type passed to RSA

i am using shared preferences to store the user name and password in order to achieve onetime user authentication. I am encrypting and storing the data in shared pref file. Again i am decrypting them and validating the values every time the user open the application. It is working fine until the App is running on background.
If the user close the app from background i am again getting the login screen asking to input the user credentials.
Below is the error:
W/System.err: java.security.InvalidKeyException: unknown key type passed to RSA
W/System.err: at com.android.org.bouncycastle.jcajce.provider.asymmetric.rsa.CipherSpi.engineInit(CipherSpi.java:275)
W/System.err: at com.android.org.bouncycastle.jcajce.provider.asymmetric.rsa.CipherSpi.engineInit(CipherSpi.java:379)
W/System.err: at javax.crypto.Cipher.init(Cipher.java:661)
W/System.err: at javax.crypto.Cipher.init(Cipher.java:621)
Below is my encryption Algorithm. I am calling the genereteKey() method before comitting the data in to shared pref file and encrypting the data then commiting the data.
private final static String RSA = "RSA";
public static PublicKey uk;
public static PrivateKey rk;
public static void generateKey() throws Exception {
KeyPairGenerator gen = KeyPairGenerator.getInstance(RSA);
gen.initialize(512, new SecureRandom());
KeyPair keyPair = gen.generateKeyPair();
uk = keyPair.getPublic();
rk = keyPair.getPrivate();
}
private static byte[] encrypt(String text, PublicKey pubRSA) throws Exception {
Cipher cipher = Cipher.getInstance(RSA);
cipher.init(Cipher.ENCRYPT_MODE, pubRSA);
return cipher.doFinal(text.getBytes());
}
public final static String encrypt(String text) {
try {
return byte2hex(encrypt(text, uk));
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public final static String decrypt(String data) {
try {
return new String(decrypt(hex2byte(data.getBytes())));
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
private static byte[] decrypt(byte[] src) throws Exception {
Cipher cipher = Cipher.getInstance(RSA);
cipher.init(Cipher.DECRYPT_MODE, rk);
return cipher.doFinal(src);
}
public static String byte2hex(byte[] b) {
String hs = "";
String stmp = "";
for (int n = 0; n < b.length; n++) {
stmp = Integer.toHexString(b[n] & 0xFF);
if (stmp.length() == 1) hs += ("0" + stmp);
else
hs += stmp;
}
return hs.toUpperCase();
}
public static byte[] hex2byte(byte[] b) {
if ((b.length % 2) != 0) throw new IllegalArgumentException("hello");
byte[] b2 = new byte[b.length / 2];
for (int n = 0; n < b.length; n += 2) {
String item = new String(b, n, 2);
b2[n / 2] = (byte) Integer.parseInt(item, 16);
}
return b2;
}

What is the C# equivalent of the Java SecretKeySpec

I have following code written in Java
Mac mac = Mac.getInstance("HmacSHA1");
String secretKey ="sKey";
String content ="Hello";
byte[] secretKeyBArr = secretKey.getBytes();
byte[] contentBArr = content.getBytes();
SecretKeySpec secret_key = new SecretKeySpec(secretKeyBArr,"HmacSHA1");
byte[] secretKeySpecArr = secret_key.getEncoded();
mac.init(secret_key);
byte[] final = mac.doFinal(contentBArr);
I want to make same example in C#. So, I wrote following code
HMACSHA1 hmacsha1 = new HMACSHA1();
string secretKey = "sKey";
string content = "Hello";
byte[] secretKeyBArr = Encoding.UTF8.GetBytes(secretKey);
byte[] contentBArr = Encoding.UTF8.GetBytes(content);
hmacsha1.Key = secretKeyBArr;
byte[] final = hmacsha1.ComputeHash(contentBArr);
Final results are not equal. secretKeyBArr and contentBArr are byte array and their values are same in both example. What is unknown is SecretKeySpec passed to mac.init(). So, what is equivalent same class in C#?

The results are identical, but Java uses signed bytes while C# uses unsigned bytes by default.
Furthermore, SecretKeySpec itself normally does not change the underlying data. You need to e.g. put a DES key specification in a SecretKeyFactory to make sure that the parity bits are set correctly (in the resulting SecretKey). So there is no need for an equivalent as the class itself does very little except wrapping the data.

I'm implementing a credit card payment method form a provider (cardinity) that doesn't provide a .net implementation. I'm looking for similar stuff and end-up writing my own as my google skills seem to be ....
What I need is the base64 string of javax.crypto.mac
I am supporting the following methods:
enum EncryptionMethods
{
None=0,
HMACSHA1,
HMACSHA256,
HMACSHA384,
HMACSHA512,
HMACMD5
}
I have implemented the code you have above, the SecretKeySpec and the Mac the following way (you need System.Security.Cryptography.ProtectedData):
internal class Protected
{
private Byte[] salt = Guid.NewGuid().ToByteArray();
protected byte[] Protect(byte[] data)
{
try
{
return ProtectedData.Protect(data, salt, DataProtectionScope.CurrentUser);
}
catch (CryptographicException)//no reason for hackers to know it failed
{
return null;
}
}
protected byte[] Unprotect(byte[] data)
{
try
{
return ProtectedData.Unprotect(data, salt, DataProtectionScope.CurrentUser);
}
catch (CryptographicException)//no reason for hackers to know it failed
{
return null;
}
}
}
internal class SecretKeySpec:Protected,IDisposable
{
readonly EncryptionMethods _method;
private byte[] _secretKey;
public SecretKeySpec(byte[] secretKey, EncryptionMethods encryptionMethod)
{
_secretKey = Protect(secretKey);
_method = encryptionMethod;
}
public EncryptionMethods Method => _method;
public byte[] SecretKey => Unprotect( _secretKey);
public void Dispose()
{
if (_secretKey == null)
return;
//overwrite array memory
for (int i = 0; i < _secretKey.Length; i++)
{
_secretKey[i] = 0;
}
//set-null
_secretKey = null;
}
~SecretKeySpec()
{
Dispose();
}
}
internal class Mac : Protected,IDisposable
{
byte[] rawHmac;
HMAC mac;
public Mac(SecretKeySpec key, string data)
{
switch (key.Method)
{
case EncryptionMethods.HMACMD5:
mac = new HMACMD5(key.SecretKey);
break;
case EncryptionMethods.HMACSHA512:
mac = new HMACSHA512(key.SecretKey);
break;
case EncryptionMethods.HMACSHA384:
mac = new HMACSHA384(key.SecretKey);
break;
case EncryptionMethods.HMACSHA256:
mac = new HMACSHA256(key.SecretKey);
break;
case EncryptionMethods.HMACSHA1:
mac = new HMACSHA1(key.SecretKey);
break;
default:
throw new NotSupportedException("not supported HMAC");
}
rawHmac = Protect( mac.ComputeHash(Cardinity.ENCODING.GetBytes(data)));
}
public string AsBase64()
{
return System.Convert.ToBase64String(Unprotect(rawHmac));
}
public void Dispose()
{
if (rawHmac != null)
{
//overwrite memory address
for (int i = 0; i < rawHmac.Length; i++)
{
rawHmac[i] = 0;
}
//release memory now
rawHmac = null;
}
mac?.Dispose();
mac = null;
}
~Mac()
{
Dispose();
}
}
I have implemented this in an OAuthSigner class the following way:
public override string ComputeSignature(string plainTextToEncode, string consumerSecret)
{
var key = PercentEncode(consumerSecret) + "&";
try
{
using (var secretKey = new SecretKeySpec(key.GetBytes(), EncryptionMethods.HMACSHA1))
using (Mac mac = new Mac(secretKey, plainTextToEncode))
{
return mac.AsBase64();
}
}
finally
{
key = null;//free memory, remove sensitive data
}
}
Then, it's not what you ask for but I need a helper method as I am sending my text to a web service that goes like this and I include it as some might copy the code:
public static String PercentEncode(string textToEncode)
{
return string.IsNullOrEmpty(textToEncode)
?""
: UrlEncoder.Default.Encode(Cardinity.ENCODING.GetString(Cardinity.ENCODING.GetBytes(textToEncode)))
.Replace("+", "%20").Replace("*", "%2A")
.Replace("%7E", "~");
}
The class UrlEncoder comes from System.Text.Encodings.Web, you may have to add a reference.
The class named Cardinity implements a "short-cut" to the Encoding that I use for Cardinity
public abstract class Cardinity
{
...
public static String API_BASE = "https://api.cardinity.com";
public static String API_VERSION = "v1";
public static String VERSION = "0.1";
public static String ENCODING_CHARSET = "UTF-8";
public static Encoding ENCODING => Encoding.UTF8;
}
as Java uses string.GetBytes a lot, I have added an extension method for this that I call above in the key.GetBytes(), here is the extension code:
public static byte[] GetBytes(this string sender)=>
Cardinity.ENCODING.GetBytes(sender);
My test method, I have copied the values from Cardinity API passes without any issues.
private OAuthSigner signer;
public HmacOAuthSigner_Test()
{
signer = new HmacOAuthSigner();
}
[TestMethod]
public void Test_HmacOAuthSigner_ComputeSignature_DefaultText()
{
var expects = "PxkffxyQh6jsDNcgJ23GpAxs2y8=";
var test_data = "justsomerandommessage";
var secretkey = "yvp0leodf231ihv9u29uuq6w8o4cat9qz2nkvs55oeu833s621";
var actual = signer.ComputeSignature(test_data, secretkey);
Assert.AreEqual(expects, actual, $"Expecting {test_data} to return {expects} received {actual}");
}
The whole implementation of the HmacOAuthSigner is here, it implements an abstract class with the PercentEncode method in it.
public class HmacOAuthSigner : OAuthSigner
{
public override string ComputeSignature(string signatureBaseString, string consumerSecret)
{
var key = PercentEncode(consumerSecret) + "&";
var secretKey = new SecretKeySpec(key.GetBytes(), EncryptionMethods.HMACSHA1);
using (Mac mac = new Mac(secretKey, signatureBaseString))
{
return mac.AsBase64();
}
}
public override string GetSignatureMethod()
{
return "HMAC-SHA1";
}
}
and the abstract class that I use as a contract for all the implementations:
public abstract class OAuthSigner
{
/// <summary>
/// Signature method used
/// </summary>
/// <returns>a string that tells the implementation method</returns>
public abstract string GetSignatureMethod();
/// <summary>
/// computes the signature that is used with the encryption based on the keys provided by cardinity
/// </summary>
/// <param name="signatureBaseString">The secret string that services as a base</param>
/// <param name="consumerSecret">The consumer key as specified in the API settings</param>
/// <returns>signature string computed by the provided parameters using the signature method</returns>
public abstract string ComputeSignature(String signatureBaseString, String consumerSecret);
/// <summary>
/// Encode a string into a format expected by Cardinity
/// </summary>
/// <param name="textToEncode">The text that is to be encoded</param>
/// <returns>web encoded string ready for using to send to Cardinity</returns>
public static String PercentEncode(string textToEncode)
{
return string.IsNullOrEmpty(textToEncode)
?""
: UrlEncoder.Default.Encode(Cardinity.ENCODING.GetString(Cardinity.ENCODING.GetBytes(textToEncode)))
.Replace("+", "%20").Replace("*", "%2A")
.Replace("%7E", "~");
}
}