So I am not the Crypto wizard by any means but here is some code I have that works in C# but does not return the same b64 string in Java.
c#
string _Cert = "long b64 string here";
string _Pass = "my password";
string lvreturn = "Test";
byte[] lvCertBytes = Convert.FromBase64String(_Cert);
X509Certificate2 lvCertFromBytes = new X509Certificate2(lvCertBytes, _Pass);
SHA1Managed lvSHA1 = new SHA1Managed();
byte[] lvData = Encoding.Unicode.GetBytes(lvReturn);
byte[] lvHash = lvSHA1.ComputeHash(lvData);
RSACryptoServiceProvider lvCryptoProvider = (RSACryptoServiceProvider)lvCertFromBytes.PrivateKey;
byte[] lvSignedBytes = lvCryptoProvider.SignHash(lvHash, CryptoConfig.MapNameToOID("SHA1"));
string lvToken = Convert.ToBase64String(lvSignedBytes);
Java
String certB64 = "long b64 string here";
char[] Pass = "text password".toCharArray();
String alias = "guid looking ID here";
String plaintext = "Test";
byte[] certbytes = Base64.getDecoder().decode(certB64);
InputStream in = new ByteArrayInputStream(certbytes);
KeyStore keystore = KeyStore.getInstance("PKCS12");
keystore.load(in,Pass);
KeyStore.PrivateKeyEntry pvk = (KeyStore.PrivateKeyEntry)keystore.getEntry(alias, new KeyStore.PasswordProtection(Pass));
PrivateKey pkey = (PrivateKey)pvk.getPrivateKey();
Signature rsa = Signature.getInstance("SHA1withRSA");
rsa.initSign(pkey);
rsa.update(plaintext.getBytes());
System.out.println("Hash: " + Base64.getEncoder().encodeToString(rsa.sign()));
I have Cert.pfx file that I want to use to use the privatekey to encrypt a https auth segment. I am just ripping the file to a base64 string and stuffing it into the "_Cert" var in C#. I do the same in Java. I want to sign the plaintext message using the private key of the cert and SHA1. The C# code below works and the https server provides a response. Java however is not spitting out the same base64 encoded string. Thanks for some help!
Update: I found a link to another post that is the same as mine but with a couple small diffs, and I didn't want to necro post on it. I followed it exactly removing the messagedigest piece of my original code. I tried reading directly from the pfx file or using the b64 string directly in the code. I am still not getting the same between Java and C#. At this point it has to be something small I am missing with encoding in Java because the C# is basically identical to mine.
Java Digital Signature different to C#
Related
My application uses salted hash in Java. First a random salt is generated. Then this salt is prefixed to the SHA-512 of the input password and the combined string is SHA-512 again.It is implemented as follows:-
String password = testpwd.getText().toString();
SecureRandom rand = new SecureRandom();
byte[] randbytes = new byte[16];
rand.nextBytes(randbytes);
String encodedSalt = Base64.encodeToString(randbytes, Base64.DEFAULT);
MessageDigest digest = MessageDigest.getInstance("SHA-512");
digest.reset();
digest.update(password.getBytes("utf-8"));
byte[] pwdhash = digest.digest();
String encodedPwd = Base64.encodeToString(pwdhash, Base64.DEFAULT);
String saltedPassword = encodedSalt+encodedPwd ;
digest.reset();
digest.update(saltedPassword.getBytes("utf-8"));
byte[] pwdhash1 = digest.digest();
String encodedPwdSalt = Base64.encodeToString(pwdhash1, Base64.DEFAULT);
Then the strings encodedSalt and encodedPwdSalt are sent to web server for authentication. The PHP encryption is as follows:
$postpassword = $_POST['password'];
$postsalt = $_POST['salt'];
$salt = base64_decode($postsalt);
$password = base64_decode('postpassword');
The SHA-512 hashs of the password "Ditglt#785" is stored in the database. It is retrieved and processed as follows:-
$getsaltpwd = $salt.$dbpassword ;
$dbsaltpwd = hash('sha512', $getsaltpwd);
if($dbpassword == $postpassword) {}
The condition always fails and so does the authentication. What should I do ?
The PHP version hashes raw bytes while the Java version hashes base64-encoded strings.
Here's a Java version that matches what your PHP code does:
digest.reset();
digest.update(randbytes);
digest.update(pwdhash);
byte[] pwdhash1 = digest.digest();
String encodedPwdSalt = Base64.encodeToString(pwdhash1, Base64.DEFAULT);
Having said that, it would be more secure to store the salt and the salted password in the database, and to use at least some key derivation function (iterate the hash function many times) in order to counteract any potential brute-forcing of the stored hashes.
Since your Java code correctly follows what you describe in your specification, the problem lies on the PHP side.
With your Java code as-is, it generates the following values when encoding the string "password" with a random salt:
encodedSalt: ww0g+f77ygKD7Iww1GTYtg==
encodedPwd: sQnzu7wkTrgkQZF+0G1hi5AI3Qmzvv0bXgc5THBqi7mAsdd4Xll27ASbRt9fEyavWi6m0QP9B8lThf+rDKy8hg==
encodedPwdSalt: YAGG7GcpUxIZzBnHuaezPf5BWFhFalBPgvue/0wFoRLu+JsKslG8wPCv6dPubIBk1aFIJ8spK8S17347aDBAYA==
In PHP, what you would need to do is the following:
$postpassword = 'YAGG7GcpUxIZzBnHuaezPf5BWFhFalBPgvue/0wFoRLu+JsKslG8wPCv6dPubIBk1aFIJ8spK8S17347aDBAYA==';
$postsalt = 'ww0g+f77ygKD7Iww1GTYtg==';
$dbpassword = 'sQnzu7wkTrgkQZF+0G1hi5AI3Qmzvv0bXgc5THBqi7mAsdd4Xll27ASbRt9fEyavWi6m0QP9B8lThf+rDKy8hg==';
if($postpassword == base64_encode(hash('sha512', $postsalt.$dbpassword, true))) {
echo 'OK';
}
Check if the padding matches. I experienced the same problem with encryption where the padding in PHP was different from the padding in JAVA. Luckily I was able to set the padding in JAVA to the one that PHP uses. But I had to look at PHP source code to figure out how. As far as I remember it was not possible to change the padding in PHP back then.
Here is the question I posted back then: decrypting php encrypted data on android
[...] you need to set Base64.decode with the parameter Base64.NO_WRAPas PHP will just put out the base64 delimited by \0.
I have DES Encryption Algorithm implementation in JAVA (javax.crypto.Cipher), it is successfully encoding and decoding (most) strings... the problem is that, sometimes, it message specific blocks (since DES uses 8-character blocks in block mode).
In my case, almost always the 3rd block is messed up and rest shows fine.
for example:
key: thisiskey
message to encrypt: Google is an American multinational technology company specializing in Internet-related services
encrypted message (in UTF-8):
mñqè•ÀPŒ�øf"
ߦ\±õ¤ù'È9¢ëyT ÍQEÁ|;ëâÉ÷JWú
Now, when i go and decrypt this, i get this:
Decrypted message:
Google i,í\O¯‹Ýbº-¸�¬ltinational technology company specializHôJ—=ÊÍnternet-related services
As far as i understand the issue, it is due to the fact that UTF-8 CANNOT show all characters and thus, while showing as well as copying for decryption, this problem occurs.
Can anyone suggest me a solution?
Preferably, either a character-set that can handle this, or, a way to convert Binary directly to HEX (that can be output to user) and then Vice Versa (decrypted, after copying/pasting) in JAVA.
EDIT
This is 'approximate' code, not exact (for example encrypted message is not properly paste-able and these are parts of the function, but it should give the idea). Even in base64 encoding , i am unable to get this decrypted properly.
Encrypt Function code:
boolean base64 = true;
key = "thisiskey";
plainText = "Google is an American multinational technology company specializing in Internet-related services";
SecretKeyFactory MyKeyFactory = SecretKeyFactory.getInstance("DES");
byte[] keyBytes = key.getBytes();
DESKeySpec generatedKeySpec = new DESKeySpec(keyBytes);
SecretKey generatedSecretKey = MyKeyFactory.generateSecret(generatedKeySpec);
Cipher generatedCipher = Cipher.getInstance("DES");
generatedCipher.init(Cipher.ENCRYPT_MODE, generatedSecretKey);
byte[] messsageStringBytes = plainText.getBytes();
byte[] encryptedMessage = generatedCipher.doFinal(messsageStringBytes);
String encryptedMessageString = new String(encryptedMessage);
if (base64) {
encryptedMessageString = Base64.getEncoder().encodeToString(encryptedMessageString.getBytes("utf-8"));
}
return encryptedMessageString;
Decrypt Function code:
boolean dbase64 = true;
dkey = "thisiskey";
messageToDecrypt = "mñqè•ÀPŒ�øf\"ߦ\±õ¤ù'È9¢ëyT ÍQEÁ|;ëâÉ÷JWú"; // Message from above code
SecretKeyFactory MyKeyFactory = SecretKeyFactory.getInstance("DES");
byte[] dkeyBytes = dkey.getBytes();
DESKeySpec generatedKeySpec = new DESKeySpec(dkeyBytes);
SecretKey generatedSecretKey = MyKeyFactory.generateSecret(generatedKeySpec);
Cipher generatedCipher = Cipher.getInstance("DES");
generatedCipher.init(Cipher.DECRYPT_MODE, generatedSecretKey);
if (dbase64) {
byte[] decodedBytes = Base64.getDecoder().decode(dencryptedText);
dencryptedText = new String(decodedBytes, "utf-8");
}
byte[] messsageStringBytes = dencryptedText.getBytes();
byte[] encryptedMessage = generatedCipher.doFinal(messsageStringBytes);
String decryptedMessageString = new String(encryptedMessage);
return decryptedMessageString;
"Encrypted message in UTF-8" makes no sense. The ciphertext is binary and not UTF-8. You need to put it into a byte[], not a String.
If you need a String, use Base64 or Hex encoding.
Even in base64 encoding , i am unable to get this decrypted properly.
String encryptedMessageString = new String(encryptedMessage);
if (base64) {
encryptedMessageString = Base64.getEncoder().encodeToString(encryptedMessageString.getBytes("utf-8"));
}
That does not work. You are encoding to Base64 after the data is already broken (by calling new String). Do not put it in a String at all. Go directly from encryptedMessage (the byte[]) to Base64.
I'm trying to implement digital signature in php as in java sample code below:
Signature rsaSig = Signature.getInstance("MD5withRSA");
RSAPrivateKey clientPrivateKey = readPrivateKeyFromFile(fileName);
rsaSig.initSign(clientPrivateKey);
String source = msg;
byte temp[] = source.getBytes();
rsaSig.update(temp);
byte sig[] = rsaSig.sign();
BASE64Encoder encoder = new BASE64Encoder();
return encoder.encode(sig);
My php code :
$rsa = new Crypt_RSA();
$rsa->loadKey('...'); // in xml format
$plaintext = '...';
$rsa->setSignatureMode(CRYPT_RSA_SIGNATURE_PKCS1);
$signature = $rsa->sign($plaintext);
But looks like some thing is missing. We should get same signature as java code returns.Can anybody guide me in this?
By default phpseclib uses sha1 as the hash. You probably need to do $rsa->setHash('md5').
I'm converting a php script to java (for android) but find myself stuck converting the hmac signature process.
PHP which gives correct sign:
$secret = "lT4fhviR7ILvwGeiBJgolfYji1uz/f7B6HQWaWQWVl/sWEz3Kwt4QjzCHWE+MBENOmtgBS6PlN87s+1d7/8bRw==";
$nonce = "1388256620813308";
$postdata = "nonce=1388256620813308";
$path = "/0/private/Balance";
$sign = hash_hmac('sha512', $path . hash('sha256', $nonce . $postdata, true), base64_decode($this->secret), true);
echo $sign;
Hmac = 2IVoBCoadCEivxKVRB/4quJET4DoZV4JdY6bMC2oEYJZuygF5JiAhGrxVMyw2yPhz+KdiwvbzV43cicGamzr2A==
Which is correct and accepted signature
Java (with invalid sign):
String secret = "lT4fhviR7ILvwGeiBJgolfYji1uz/f7B6HQWaWQWVl/sWEz3Kwt4QjzCHWE+MBENOmtgBS6PlN87s+1d7/8bRw==";
String nonce = "1388256620813308";
String postdata = "nonce=1388256620813308";
String path = "/0/private/Balance";
// hash nonce + data
MessageDigest md = MessageDigest.getInstance("SHA-256");
md.update((nonce+postdata).getBytes());
byte[] digest = md.digest();
String baseString = path + new String(digest); //this is probably root of evil
// HMAC
Mac mac = Mac.getInstance("HmacSHA512");
SecretKey secretKey = new SecretKeySpec(Base64.decode(secret, Base64.DEFAULT), "HmacSHA512");
mac.init(secretKey);
String sign = new String(Base64.encodeToString(mac.doFinal(baseString.getBytes()), Base64.DEFAULT)).trim();
Log.d(TAG, sign);
Hmac = 7ZQfn+fqMpMEFN5Z/T5UwcqP1uo0JOyAVSn4HEBeE/KotnEf4a5bPOWriiC//gdoEg2kOe60EIr3Lv7irXuejw==
The problem is in the java string conversion of the bytes (even if I add "UTF-8" as characted encoding in getBytes). I know this because if I don add path to the hmac, and just feed it with digest without the string conversion the signature matches.
After posting question I did a quick and dirty test to add bytes from path manually to a new bytes array
byte[] digest = md.digest();
byte[] pBytes = path.getBytes();
int L = digest.length + pBytes.length;
byte[] message = new byte[L];
for (int i=0;i<pBytes.length;i++) {
message[i] = pBytes[i];
}
for (int i=pBytes.length,n=0; n<digest.length; n++) {
message[i+n] = digest[n];
}
String sign = new String(Base64.encodeToString(mac.doFinal(message), Base64.NO_WRAP));
And voilà; the hmac sign matches!
I have solved my problem but keeping question unanswered for some day to say if a better answer is provided that sheds light on this.
I'm trying to encrypt stuff in java using the public key generated by my PHP:
PHP Code
$rsa = new Crypt_RSA();
$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);
$rsa->setPrivateKeyFormat(CRYPT_RSA_PRIVATE_FORMAT_PKCS1);
$rsa->setPublicKeyFormat(CRYPT_RSA_PUBLIC_FORMAT_PKCS1);
$keys = $rsa->createKey(1024);
extract($keys);
echo (base64_encode($publickey));
For testing purposes, I've set aside a keypair (base64) of the above format.
I retrieve my Public Key in java and base64 decode it.
String publicKeyDecoded = new String(Base64.decode(publicKey));
PEMParser pr = new PEMParser(new StringReader(publicKeyDecoded));
Object obj = pr.readObject();
pr.close();
SubjectPublicKeyInfo spki = (SubjectPublicKeyInfo) obj;
AsymmetricKeyParameter askp = PublicKeyFactory.createKey(spki);
AsymmetricBlockCipher e = new RSAEngine();
e = new org.bouncycastle.crypto.encodings.PKCS1Encoding(e);
e.init(true, askp);
byte[] messageBytes = plainText.getBytes();
byte[] encryptedData = e.processBlock(messageBytes, 0, messageBytes.length);
byte[] encryptedDataBase = Base64.encode(encryptedData);
I send the Base64 encrypted plaintext back to PHP for decryption using the following:
$rsa->loadKey($privatekey) or die ("Cant load");
echo $rsa->decrypt($cipher);
It's unable to decrpyt my encoded message and throws me the error:
Decryption error in <b>/opt/lampp/htdocs/Crypt/RSA.php</b> on line <b>2120</b>
Can someone point me to the right direction? It's been hours since I'm trying to figure this out.
I'm using a hardcoded keypair so I guess there's no question of my keys being wrong...
To answer my own question:
Everything apart from the final decryption PHP was correct.
It should be:
$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);
$rsa->setPrivateKeyFormat(CRYPT_RSA_PRIVATE_FORMAT_PKCS1);
$rsa->setPublicKeyFormat(CRYPT_RSA_PUBLIC_FORMAT_PKCS1);
$rsa->loadKey(base64_decode($_SESSION['private'])) or die ("Cant load");
echo $rsa->decrypt(base64_decode($cipher));
I forgot to un-base64 my encrypted text sent from java and to set the encryption modes.
Thanks neubert.