Java Requires Chilkat v11.0.0+

RSA Encrypt Hash using SHA256 hash function and SHA1 mask function

See more RSA Examples

How can this Javascript be duplicated using Chilkat?

function a(e, t) {
                var r = s.pki.publicKeyFromPem(e)
                  , n = r.encrypt(t, "RSA-OAEP", {
                    md: s.md.sha256.create(),
                    mgf1: {
                        md: s.md.sha1.create()
                    }
                });
                return s.util.encode64(n)
            }

Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens, even using the same data and key, the result will be different -- but still valid. One should not expect to get the same output.

Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Crypt2;
import com.chilkatsoft.chilkat2.PublicKey;
import com.chilkatsoft.chilkat2.Rsa;
import com.chilkatsoft.chilkat2.StringBuilder;

public class ChilkatExample {

    public static void main(String[] args) {
        // This example requires the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        PublicKey pubkey = new PublicKey();

        StringBuilder sbPem = new StringBuilder();
        boolean bCrlf = true;
        sbPem.appendLine("-----BEGIN PUBLIC KEY-----", bCrlf);
        sbPem.appendLine("MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF", bCrlf);
        sbPem.appendLine("3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA", bCrlf);
        sbPem.appendLine("04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s", bCrlf);
        sbPem.appendLine("Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF", bCrlf);
        sbPem.appendLine("wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE", bCrlf);
        sbPem.appendLine("f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W", bCrlf);
        sbPem.appendLine("SwIDAQAB", bCrlf);
        sbPem.appendLine("-----END PUBLIC KEY-----", bCrlf);

        // Load the public key object from the PEM.
        try {
            pubkey.loadFromString(sbPem.getAsString());
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        String originalData = "This is the original data to be SHA-256 hashed and RSA encrypted.";

        // First we SHA-256 hash the original data to get the hash in base64 format:
        Crypt2 crypt = new Crypt2();
        crypt.setHashAlgorithm("SHA-256");
        crypt.setEncodingMode("base64");
        String hashBase64 = crypt.hashStringENC(originalData);

        // Setup RSA to use OAEP padding with SHA-1 for the mask function.
        Rsa rsa = new Rsa();
        rsa.setPkcsPadding(false);
        rsa.setOaepHash("SHA256");
        rsa.usePublicKey(pubkey);
        rsa.setEncodingMode("base64");

        // We can provide a binary encoding mode, such as "base64", "hex", "base64url", etc.
        // for the Charset property.   The Charset property was previously limited to character encodings, such as
        // "utf-8", "iso-8859-1", etc.  If a binary encoding is used, then the string passed in is decoded to the binary
        // bytes as indicated.  (If an actual charset, such as "utf-8" is used, then the input string is converted to the
        // byte representation of the charset, and then encrypted.)

        // Given that a hash is composed of non-text binary bytes, we'll set the Charset property equal to "base64"
        // (because we have the base64 hash from above).
        rsa.setCharset("base64");

        // Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens,
        // even using the same data and key, the result will be different --  but still valid.  One should not expect
        // to get the same output.
        boolean bUsePrivateKey = false;
        String encryptedStr;
        try {
            encryptedStr = rsa.encryptStringENC(hashBase64, bUsePrivateKey);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("Base64 RSA encrypted output: " + encryptedStr);
    }
}