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Java Requires Chilkat v11.0.0+

JWS Using RSASSA-PSS using SHA-256 and MGF1 with SHA-256

See more JSON Web Signatures (JWS) Examples

Creates and validates a JSON Web Signature (JWS) using RSASSA-PSS using SHA-256 and MGF1 with SHA-256.

Chilkat supports all of the following JWS algorithms:

   +--------------+-------------------------------+--------------------+
   | "alg" Param  | Digital Signature or MAC      | Implementation     |
   | Value        | Algorithm                     | Requirements       |
   +--------------+-------------------------------+--------------------+
   | HS256        | HMAC using SHA-256            | Required           |
   | HS384        | HMAC using SHA-384            | Optional           |
   | HS512        | HMAC using SHA-512            | Optional           |
   | RS256        | RSASSA-PKCS1-v1_5 using       | Recommended        |
   |              | SHA-256                       |                    |
   | RS384        | RSASSA-PKCS1-v1_5 using       | Optional           |
   |              | SHA-384                       |                    |
   | RS512        | RSASSA-PKCS1-v1_5 using       | Optional           |
   |              | SHA-512                       |                    |
   | ES256        | ECDSA using P-256 and SHA-256 | Recommended+       |
   | ES384        | ECDSA using P-384 and SHA-384 | Optional           |
   | ES512        | ECDSA using P-521 and SHA-512 | Optional           |
   | PS256        | RSASSA-PSS using SHA-256 and  | Optional           |
   |              | MGF1 with SHA-256             |                    |
   | PS384        | RSASSA-PSS using SHA-384 and  | Optional           |
   |              | MGF1 with SHA-384             |                    |
   | PS512        | RSASSA-PSS using SHA-512 and  | Optional           |
   |              | MGF1 with SHA-512             |                    |
   +--------------+-------------------------------+--------------------+

Chilkat Java Downloads

Chilkat2 Java
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.JsonObject;
import com.chilkatsoft.chilkat2.Jws;
import com.chilkatsoft.chilkat2.PrivateKey;
import com.chilkatsoft.chilkat2.PublicKey;
import com.chilkatsoft.chilkat2.StringBuilder;

public class ChilkatExample {

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

        // Note: This example requires Chilkat v9.5.0.66 or greater.

        // Use the following RSA key loaded from JWK format.
        StringBuilder sbJwk = new StringBuilder();
        sbJwk.append("{\"kty\":\"RSA\",");
        sbJwk.append("\"n\":\"ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx");
        sbJwk.append("HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs");
        sbJwk.append("D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH");
        sbJwk.append("SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV");
        sbJwk.append("MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8");
        sbJwk.append("NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ\",");
        sbJwk.append("\"e\":\"AQAB\",");
        sbJwk.append("\"d\":\"Eq5xpGnNCivDflJsRQBXHx1hdR1k6Ulwe2JZD50LpXyWPEAeP88vLNO97I");
        sbJwk.append("jlA7_GQ5sLKMgvfTeXZx9SE-7YwVol2NXOoAJe46sui395IW_GO-pWJ1O0");
        sbJwk.append("BkTGoVEn2bKVRUCgu-GjBVaYLU6f3l9kJfFNS3E0QbVdxzubSu3Mkqzjkn");
        sbJwk.append("439X0M_V51gfpRLI9JYanrC4D4qAdGcopV_0ZHHzQlBjudU2QvXt4ehNYT");
        sbJwk.append("CBr6XCLQUShb1juUO1ZdiYoFaFQT5Tw8bGUl_x_jTj3ccPDVZFD9pIuhLh");
        sbJwk.append("BOneufuBiB4cS98l2SR_RQyGWSeWjnczT0QU91p1DhOVRuOopznQ\",");
        sbJwk.append("\"p\":\"4BzEEOtIpmVdVEZNCqS7baC4crd0pqnRH_5IB3jw3bcxGn6QLvnEtfdUdi");
        sbJwk.append("YrqBdss1l58BQ3KhooKeQTa9AB0Hw_Py5PJdTJNPY8cQn7ouZ2KKDcmnPG");
        sbJwk.append("BY5t7yLc1QlQ5xHdwW1VhvKn-nXqhJTBgIPgtldC-KDV5z-y2XDwGUc\",");
        sbJwk.append("\"q\":\"uQPEfgmVtjL0Uyyx88GZFF1fOunH3-7cepKmtH4pxhtCoHqpWmT8YAmZxa");
        sbJwk.append("ewHgHAjLYsp1ZSe7zFYHj7C6ul7TjeLQeZD_YwD66t62wDmpe_HlB-TnBA");
        sbJwk.append("-njbglfIsRLtXlnDzQkv5dTltRJ11BKBBypeeF6689rjcJIDEz9RWdc\",");
        sbJwk.append("\"dp\":\"BwKfV3Akq5_MFZDFZCnW-wzl-CCo83WoZvnLQwCTeDv8uzluRSnm71I3Q");
        sbJwk.append("CLdhrqE2e9YkxvuxdBfpT_PI7Yz-FOKnu1R6HsJeDCjn12Sk3vmAktV2zb");
        sbJwk.append("34MCdy7cpdTh_YVr7tss2u6vneTwrA86rZtu5Mbr1C1XsmvkxHQAdYo0\",");
        sbJwk.append("\"dq\":\"h_96-mK1R_7glhsum81dZxjTnYynPbZpHziZjeeHcXYsXaaMwkOlODsWa");
        sbJwk.append("7I9xXDoRwbKgB719rrmI2oKr6N3Do9U0ajaHF-NKJnwgjMd2w9cjz3_-ky");
        sbJwk.append("NlxAr2v4IKhGNpmM5iIgOS1VZnOZ68m6_pbLBSp3nssTdlqvd0tIiTHU\",");
        sbJwk.append("\"qi\":\"IYd7DHOhrWvxkwPQsRM2tOgrjbcrfvtQJipd-DlcxyVuuM9sQLdgjVk2o");
        sbJwk.append("y26F0EmpScGLq2MowX7fhd_QJQ3ydy5cY7YIBi87w93IKLEdfnbJtoOPLU");
        sbJwk.append("W0ITrJReOgo1cq9SbsxYawBgfp_gh6A5603k2-ZQwVK0JKSHuLFkuQ3U\"");
        sbJwk.append("}");

        PrivateKey rsaKey = new PrivateKey();
        // Note: This example loads the RSA key from JWK format.  Any format can be loaded
        // into the private key object. (See the online reference documentation..)
        try {
            rsaKey.loadJwk(sbJwk.getAsString());
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Create the JWS Protected Header
        JsonObject jwsProtHdr = new JsonObject();
        jwsProtHdr.appendString("alg", "PS256");

        Jws jws = new Jws();

        // Set the protected header:
        int signatureIndex = 0;
        jws.setProtectedHeader(signatureIndex, jwsProtHdr);

        // Set the RSA key:
        jws.setPrivateKey(signatureIndex, rsaKey);

        // Set the payload.
        boolean bIncludeBom = false;
        String payloadStr = "In our village, folks say God crumbles up the old moon into stars.";
        jws.setPayload(payloadStr, "utf-8", bIncludeBom);

        // Create the JWS
        // By default, the compact serialization is used.
        String jwsCompact;
        try {
            jwsCompact = jws.createJws();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("JWS: " + jwsCompact);

        // Note: RSA PSS padding uses random values, so the output will be different each time a signature is produced.
        // sample output:
        // JWS: eyJhbGciOiJQUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.TRWhwRo5dMv9-8OzrInfJTwmUGYgjLfHk8lqF072ND-FmLWEBnUTOpY8oJXp8FdWw2SalbdOeNlrtlJjwk4XK8Ql2iJ_2qMCtxsvLPhKBOqFoAF4aBvTOEDVJDxf0DaBSiydEEtfTVV2iwBcjWabu5J2XieR5y7QZQtuHsn7T3qKBvCcCejN3Y2oqAT3qMHvu1fTms1r_91wBn_K7Wjd9UkZ1n02qQcUHJznR_OF2BgN7_KWIDAF9ZS9keoju2NPpPelO4yxa2XUPnehY3G7dHKoCxUEQR4d2Xc5voqDASTVCDqQS4PVOZdvT3Ein6-SanAlCwbWBbkvT8g6-5PImQ

        // Now load the JWS, validate, and recover the original text.
        Jws jws2 = new Jws();

        // Load the JWS.
        jws2.loadJws(jwsCompact);

        PublicKey rsaPubKey = new PublicKey();
        rsaKey.toPublicKey(rsaPubKey);

        // Set the RSA public key used for validation.
        signatureIndex = 0;
        jws2.setPublicKey(signatureIndex, rsaPubKey);

        // Validate the 1st (and only) signature at index 0..
        int v = jws2.validate(signatureIndex);
        if (v < 0) {
            // Perhaps Chilkat was not unlocked or the trial expired..
            System.out.println("Method call failed for some other reason.");
            System.out.println(jws2.getLastErrorText());
            return;
        }

        if (v == 0) {
            System.out.println("Invalid signature.  The RSA key was incorrect, the JWS was invalid, or both.");
            return;
        }

        // If we get here, the signature was validated..
        System.out.println("Signature validated.");

        // Recover the original content:
        System.out.println(jws2.getPayload("utf-8"));

        // Examine the protected header:
        JsonObject joseHeader = new JsonObject();
        jws2.getProtectedH(signatureIndex, joseHeader);
        joseHeader.setEmitCompact(false);

        System.out.println("Protected (JOSE) header:");
        System.out.println(joseHeader.emit());

        // Output:

        //     Signature validated.
        //     In our village, folks say God crumbles up the old moon into stars.
        //     Protected (JOSE) header:
        //     {
        //       "alg": "PS256"
        //     }
    }
}