使用PhpSecLib和BouncyCastle的PHP和Java Decrpytion错误

Question

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...

Answer 1

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.