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How to convert JAVA program to PHP to carryout RSA encryption

I am trying to implement AEPS API but unable to encrypt aadhar number in php. In developer guide they provided method to encrypt using JAVA and i am using php.
Given JAVA code is as follows.
public static String calculateRSA( String salt ) throws InvalidKeyException, Exception {
Cipher encryptCipher = Cipher.getInstance("RSA");
encryptCipher.init(Cipher.ENCRYPT_MODE, getPublicKey());
byte[] secretMessageBytes = salt.getBytes("UTF-8");
byte[] encryptedMessageBytes = encryptCipher.doFinal(secretMessageBytes);
String encodedMessage = Base64.encodeBase64String(encryptedMessageBytes);
return encodedMessage;
}
public static PublicKey getPublicKey() throws Exception {
String rawPublicKey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCaFyrzeDhMaFLx+LZUNOOO14Pj9aPfr+1WOanDgDHxo9NekENYcWUftM9Y17ul2pXr3bqw0GCh4uxNoTQ5cTH4buI42LI8ibMaf7Kppq9MzdzI9/7pOffgdSn+P8J64CJAk3VrVswVgfy8lABt7fL8R6XReI9x8ewwKHhCRTwBgQIDAQAB";
byte[] keyBytes = Base64.decodeBase64(rawPublicKey);
X509EncodedKeySpec spec = new X509EncodedKeySpec(keyBytes);
KeyFactory kf = KeyFactory.getInstance("RSA");
return kf.generatePublic(spec);// generatePrivate(spec);
}
I tried
$publicKey = 'MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCaFyrzeDhMaFLx+LZUNOOO14Pj9aPfr+1WOanDgDHxo9NekENYcWUftM9Y17ul2pXr3bqw0GCh4uxNoTQ5cTH4buI42LI8ibMaf7Kppq9MzdzI9/7pOffgdSn+P8J64CJAk3VrVswVgfy8lABt7fL8R6XReI9x8ewwKHhCRTwBgQIDAQAB';
include('Crypt/RSA.php');
$rsa = new Crypt_RSA();
$rsa->loadKey($publicKey); // public key
$plaintext = '828409353766';
//$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_OAEP);
$encrypted = $rsa->encrypt($plaintext);
$encrypted = base64_encode($encrypted);

Verifying Java signature in C#

I have signature created in Java by following code
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
PrivateKey privateKey = keyFactory.generatePrivate(privateKeySpec);
signature = (Signature) rsaSha256.getCipher();
signature.initSign(privateKey);
signature.update(binaryData);
signatureBytes = signature.sign();
By verifying signature in C#, im always getting false. Following code use BouncyCastle library
ISigner signer = SignerUtilities.GetSigner("SHA256withRSA");
using (TextReader sr = new StringReader(publicKey))
{
PemReader pr = new PemReader(sr);
RsaKeyParameters keys = (RsaKeyParameters)pr.ReadObject();
signer.Init(false, keys);
signer.BlockUpdate(value, 0, value.Length);
bool isValid = signer.VerifySignature(signature);
return isValid;
}
Following code return false too
private static bool VerifyWithPublicKey(byte[] data, byte[] sig, string publicKey)
{
RSACryptoServiceProvider rsa;
using (var keyreader = new StringReader(publicKey))
{
var pemReader = new PemReader(keyreader);
var y = (RsaKeyParameters)pemReader.ReadObject();
RSAParameters p1 = DotNetUtilities.ToRSAParameters(y);
rsa = new RSACryptoServiceProvider();
rsa.ImportParameters(p1);
}
byte[] hash;
using (var sha256 = SHA256.Create())
{
hash = sha256.ComputeHash(data);
}
RSAPKCS1SignatureDeformatter RSADeformatter = new RSAPKCS1SignatureDeformatter(rsa);
RSADeformatter.SetHashAlgorithm("SHA256");
//Verify the hash and display the results to the console.
if (RSADeformatter.VerifySignature(hash, sig))
{
Console.WriteLine("The signature was verified.");
}
else
{
Console.WriteLine("The signature was NOT verified.");
}
// This always returns false
return rsa.VerifyHash(hash, CryptoConfig.MapNameToOID("SHA256"), sig);
}
Im out of ideas. Anyone done something similar? If so, can you share your code please

This works for me, I see a difference where you use .GetSigner("SHA256withRSA") but I use "SHA-256withRSA"
public static bool VerifySignature(byte[] hashBytes, byte[] signatureBytes)
{
PemReader pemReader = new PemReader(new StreamReader("PublicKey.pem"));
RsaKeyParameters parameters = (RsaKeyParameters)pemReader.ReadObject();
RsaDigestSigner signer = (RsaDigestSigner)SignerUtilities.GetSigner("SHA-256withRSA");
signer.Init(false, parameters);
signer.BlockUpdate(hashBytes, 0, hashBytes.Length);
bool isValid = signer.VerifySignature(signatureBytes);
return isValid;
}

java.security.InvalidKeyException: invalid key format on generating RSA public key

Background:
I have created an applet to extract public key of a certificate extracted from a smart card.
This public key is then stored in database.
The private key of certificate is used to sign data and the public key is then used to verify the signature.
Code for extracting public key from certificate:
private byte[] getPublicKey(KeyStore paramKeyStore)
throws GeneralSecurityException {
Enumeration localEnumeration = paramKeyStore.aliases();
if (localEnumeration.hasMoreElements()) {
String element = (String) localEnumeration.nextElement();
Certificate[] arrayOfCertificate =
paramKeyStore.getCertificateChain(element);
byte[] publicKeyByteArray =
arrayOfCertificate[0].getPublicKey().getEncoded();
return publicKeyByteArray;
}
throw new KeyStoreException("The keystore is empty!");
}
This publicKeyByteArray is then storeed in database as BLOB after converting to string using bytes2String method:
private static String bytes2String(byte[] bytes) {
StringBuilder string = new StringBuilder();
for (byte b : bytes) {
String hexString = Integer.toHexString(0x00FF & b);
string.append(hexString.length() == 1 ? "0" + hexString : hexString);
}
return string.toString();
}
The content of the BLOB(key) saved in database is:
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
After reading the stored public key byte[] from database, I try to convert it back to Public Key using following code:
Cipher rsa;
rsa = Cipher.getInstance("RSA");
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(pkey.getBytes());
PublicKey pk = keyFactory.generatePublic(publicKeySpec);
rsa.init(Cipher.DECRYPT_MODE, pk);
byte[] cipherDecrypt = rsa.doFinal(encryptedText.getBytes());
but it gives following error:
Caused by: java.security.InvalidKeyException: invalid key format
at sun.security.x509.X509Key.decode(X509Key.java:387)
at sun.security.x509.X509Key.decode(X509Key.java:403)
at sun.security.rsa.RSAPublicKeyImpl.<init>(RSAPublicKeyImpl.java:83)
at sun.security.rsa.RSAKeyFactory.generatePublic(RSAKeyFactory.java:298)
at sun.security.rsa.RSAKeyFactory.engineGeneratePublic(RSAKeyFactory.java:201)
Please suggest the reason and resolution for this issue.

You must have an error in the way you read the key back from the database. The following code works just fine for me:
String key = "3082012230..."; // full key omitted for brevity
byte[] derPublicKey = DatatypeConverter.parseHexBinary(key);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(derPublicKey);
keyFactory.generatePublic(publicKeySpec);
I would guess, based on the use of pkey.getBytes(), that you've simply tried to get the bytes from the string rather than hex-decoding it.

Why always give me false in signature?

I try in this code to verify my code, I have public key , my data and signature.I am read my signature from file and convert my string to public key then get my data and verify to signature.
public static boolean verify () {
String publickey = "MIGfMA0GCSqGSIb3DQE";
byte[] encKey = Base64.decodeBase64(publickey.getBytes());
try {
byte[] MACaddress = GetData();
BufferedReader in = new BufferedReader(new FileReader(
"EndSignatuer.txt"));
FileInputStream keyfis = new FileInputStream("EndSignatuer.txt");
byte[] Signen = new byte[keyfis.available()];
keyfis.read(Signen);
keyfis.close();
X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(encKey);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey pubKey = keyFactory.generatePublic(pubKeySpec);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, pubKey);
byte[] deSignen = Base64.decodeBase64(Signen);
byte[] decrypted_digest = cipher.doFinal(deSignen);
MessageDigest md5_digest = MessageDigest.getInstance("MD5");
md5_digest.update(MACaddress);
byte[] digest = md5_digest.digest();
if (decrypted_digest == digest) {
return true;
}else {
return false;//her why give me false
}
Code encryption:
public static void GenarationKEY(byte[] data) {
try {
File fileEndSignatuer = new File("EndSignatuer.txt");
FileOutputStream fopEndSignatuer = new FileOutputStream(
fileEndSignatuer);
// /Read private key from file
FileInputStream keyfis = new FileInputStream("PiveteKey.txt");
byte[] PrivateKeyB = new byte[keyfis.available()];
keyfis.read(PrivateKeyB);
keyfis.close();
byte[] decodePrivetekey = Base64.decodeBase64(PrivateKeyB);
// /get private key
PKCS8EncodedKeySpec pubKeySpec = new PKCS8EncodedKeySpec(
decodePrivetekey);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PrivateKey privKey = keyFactory.generatePrivate(pubKeySpec);
// / make hash
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, privKey);
// /make encoding
MessageDigest md5_digest = MessageDigest.getInstance("MD5");
byte[] digest = md5_digest.digest(data);
byte[] cipherText = cipher.doFinal(digest);
byte[] degnatureencode = Base64.encodeBase64(cipherText);
fopEndSignatuer.write(degnatureencode);
fopEndSignatuer.flush();
fopEndSignatuer.close();
}

First of all, what you do is not quite RSA digital signature. Use Signature class instead of combination Cipher and MessageDigest. Or if you insist to do it on low level, then consult specification, particularly section 9.2.
Secondly, string MIGfMA0GCSqGSIb3DQE doesn't represent RSA public key neither it is proper Base64-encoded data.
Also you want to use Arrays.equals(byte[], byte[]) instead of equality operator, as the latter just ensures that array object is the same, while the former compares actual content of the arrays.

RSA in Java given n and e

My application receives the raw pieces of a public RSA key (n and e) and needs to use these to encrypt a cipher text. I've been trying to use BouncyCastle but my code isn't working. The problem arises in trying to create the X509EncodedKeySpec.
Can anyone help me get this working? Here's the code I have:
public static PublicKey getPublicKeyFromString(String key) throws Exception
{
KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(Base64Encoder.decode(key));
PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);
return publicKey;
}
I guess the real problem is that n and e are separate and I don't know how to combine them.

Why are you not using new RSAPublicKeySpec(n,e)?

public static PublicKey getPublicKeyFromString(String key) throws Exception
{
BASE64Decoder b64 = new BASE64Decoder();
KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(b64.decodeBuffer(key));
PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);
return publicKey;
}