RSA Encrypt in PHP and Decrypt in Java or Kotlin

Decrypt.java

public class DecryptKey {
    //before you proceed, you need to ensure your public key is PKCS8 since that is what can be read natively in java.
    //If your key begins with-----BEGIN CERTIFICATE-----,
    // the it is ssleay and you need to convert it using the openssl command below
    //openssl pkcs8 -topk8 -inform pem -in public.key -outform pem -nocrypt -out pkcs8-public-key.pem
    //TODO You can you phpsecLib lib but it doesn't support some Library 
    //opnssl work fine
	final private static String RSA_PRIVATE_KEY =
			   -----BEGIN PUBLIC KEY-----
		MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAzTrKt2Y7HqQpt8w379Sl
		79mjXGJ+CF+ridXpnAKoKyN8LH1NkI08UyWEHKbtCBl4iCsy8ayr4RAkWDKzeb8p
		ZEmdOg3cHKyFT6NdUEDc0FGpgKWY6GycJUrY+1S5O256M/NRSw02mUpyYIpGjq1z
		2zfu4GWIPg24hyI4YrAVI90mknIyXduerLH30XdwnKTevwhkQ4cP+xeYLVDduodc
		pcVaSXcwBvIbwVWS7szTxNGX0qyDlmJoK6YtTZ4FJp6BK6iyD+Fpnt9Fld8d62o2
		WjAtjpc8w81kIwwykojCDv9cb2qhwryS63qlcPhgpxcpDXINBHxcONHtHSWKEb0t 
		2wIDAQAB
		-----END PUBLIC KEY-----;




    public static byte[] decrypt(String key) throws Exception {
        String privKeyPEM = RSA_PRIVATE_KEY.replace("-----BEGIN PRIVATE KEY-----\n", "");
        privKeyPEM = privKeyPEM.replace("-----END PRIVATE KEY-----", "");
        byte [] encoded = Base64.decode(privKeyPEM, Base64.DEFAULT);

        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(encoded);
        KeyFactory kf = KeyFactory.getInstance("RSA");
        PrivateKey privKey = kf.generatePrivate(keySpec);

        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "BC");
        cipher.init(Cipher.DECRYPT_MODE, privKey);

        byte[] decodedStr           = Base64.decode(key, Base64.DEFAULT);
        byte[] plainText            = cipher.doFinal(decodedStr);

        return plainText;
    }
}

Decrypt.kt

open class DecryptKey {

    //before you proceed, you need to ensure your public key is PKCS8 since that is what can be read natively in java.
    //If your key begins with-----BEGIN CERTIFICATE-----,
    // the it is ssleay and you need to convert it using the openssl command below
    //openssl pkcs8 -topk8 -inform pem -in public.key -outform pem -nocrypt -out pkcs8-public-key.pem
    //TODO You can you phpsecLib lib but it doesn't support some Library 
    //opnssl work fine

    private val RSA_PRIVATE_KEY = "-----BEGIN PRIVATE KEY-----\n" +
            "MI...\n" +
            "2...\n" +
            "HPt...\n" +
            "v3...\n" +
            "-----END PRIVATE KEY-----"


    @Throws(Exception::class)
    fun decrypt(key: String): ByteArray {
        var privKeyPEM = RSA_PRIVATE_KEY.replace("-----BEGIN PRIVATE KEY-----\n", "")
        privKeyPEM = privKeyPEM.replace("-----END PRIVATE KEY-----", "")
        val encoded = Base64.decode(privKeyPEM, Base64.DEFAULT)


        val keySpec = PKCS8EncodedKeySpec(encoded)
        val kf = KeyFactory.getInstance("RSA")
        val privKey = kf.generatePrivate(keySpec)

        val cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "BC")
        cipher.init(Cipher.DECRYPT_MODE, privKey)

        val decodedStr = Base64.decode(key, Base64.DEFAULT)

        return cipher.doFinal(decodedStr)
    }
}

Encrypt.php

<?php
function encrypt($string) 
{
	$key = 
"-----BEGIN PUBLIC KEY-----
MIGfM....
gUn....
7eMl....
yXd....
-----END PUBLIC KEY-----";
	openssl_public_encrypt($string, $crypted, $key);
		
        
    return base64_encode($crypted);
}

encryptToString

public String encryptToString(byte[] data) {
        Security.addProvider(new BouncyCastleProvider());
        byte[] cipherData = null;
        try {
            X509Certificate cert = this.getPublicKey(public_key_alias, keystore_pass, keystore_location);
            Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "BC");
            cipher.init(Cipher.ENCRYPT_MODE, cert.getPublicKey());

            cipherData = cipher.doFinal(data);


        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return Base64.encodeBase64String(cipherData);
    }

04 July 20