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Java Requires Chilkat v11.0.0+

Validate JWS with Multiple Signatures using the General JSON Serialization Format

See more JSON Web Signatures (JWS) Examples

Validates and recovers data and headers from a JSON Web Signature (JWS) containing 3 signatures.

Note: 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.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.

        // First, prepare the public keys that will be needed for each signature.

        // ---------------------------------------------------
        // Use the following RSA key loaded from JWK format.
        StringBuilder sbRsaJwk = new StringBuilder();
        sbRsaJwk.append("{\"kty\":\"RSA\",");
        sbRsaJwk.append("\"n\":\"ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx");
        sbRsaJwk.append("HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs");
        sbRsaJwk.append("D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH");
        sbRsaJwk.append("SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV");
        sbRsaJwk.append("MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8");
        sbRsaJwk.append("NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ\",");
        sbRsaJwk.append("\"e\":\"AQAB\"");
        sbRsaJwk.append("}");

        PublicKey rsaKey = new PublicKey();
        try {
            rsaKey.loadFromString(sbRsaJwk.getAsString());
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // ---------------------------------------------------
        // Use the following ECC public key loaded from JWK format.
        StringBuilder sbEccJwk = new StringBuilder();
        sbEccJwk.append("{\"kty\":\"EC\",");
        sbEccJwk.append("\"crv\":\"P-256\",");
        sbEccJwk.append("\"x\":\"f83OJ3D2xF1Bg8vub9tLe1gHMzV76e8Tus9uPHvRVEU\",");
        sbEccJwk.append("\"y\":\"x_FEzRu9m36HLN_tue659LNpXW6pCyStikYjKIWI5a0\"");
        sbEccJwk.append("}");

        PublicKey eccKey = new PublicKey();
        try {
            eccKey.loadFromString(sbEccJwk.getAsString());
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // ---------------------------------------------------
        // The HMAC key (in base64url format)
        String hmacKey = "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow";

        // The code below will verify each of the signatures in this JWS:

        // {
        //   "payload": "SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu",
        //   "signatures": [
        //     {
        //       "protected": "eyJhbGciOiJSUzI1NiIsImtpZCI6Im15UnNhS2V5In0",
        //       "signature": "IPMQ02niTQDwLzsRZSCaEm9VEyAX_AVe3HWjniNt9kW-a8d6ZVbd2k6jGae8s1yIh0cgxDnXQ6-p6_sBI0cnMO0xpuJANhh2vFtNJl5lisad94-H3mB3lSfafRqxeYp5D8bh39BPv7y3PrUNVMQdKEJp_D5oJ0ROPTIYx3EG8eJQOx1HO0KqhcUo401XR6KSsIyFm5joBLNKTVzxZUTT1RRZZtwTdeZkbGevugIOX_9gHAtARpV6WaFA4Vvjnq8X9wPgqjWNCQRupadhTPz0JAsa-wy5vXQjsFlXAn43mDPpMfna5Ab3F5pS4yDwkbX6nRn7XBxH1SnnNJRFholQZw"
        //     },
        //     {
        //       "protected": "eyJhbGciOiJFUzI1NiIsImtpZCI6Im15RWNLZXkifQ",
        //       "signature": "1OQtaT3pgZmkDxvlfghvxL_8kX16WIen6u1MadEq1pA4qytA0--_EwZDNk00GDPWFpoJtKznibMZzLOg_UhHIw"
        //     },
        //     {
        //       "protected": "eyJhbGciOiJIUzI1NiIsImtpZCI6Im15TWFjS2V5In0",
        //       "signature": "YY8yVjmJJfy7YJOn3uUydG8WCY2PEuCvOLil5Ks5lnw"
        //     }
        //   ]
        // }

        StringBuilder sbJws = new StringBuilder();
        sbJws.append("{ ");
        sbJws.append("  \"payload\": \"SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu\",");
        sbJws.append("  \"signatures\": [");
        sbJws.append("    { ");
        sbJws.append("      \"protected\": \"eyJhbGciOiJSUzI1NiIsImtpZCI6Im15UnNhS2V5In0\",");
        sbJws.append("      \"signature\": \"IPMQ02niTQDwLzsRZSCaEm9VEyAX_AVe3HWjniNt9kW-a8d6ZVbd2k6jGae8s1yIh0cgxDnXQ6-p6_sBI0cnMO0xpuJANhh2vFtNJl5lisad94-H3mB3lSfafRqxeYp5D8bh39BPv7y3PrUNVMQdKEJp_D5oJ0ROPTIYx3EG8eJQOx1HO0KqhcUo401XR6KSsIyFm5joBLNKTVzxZUTT1RRZZtwTdeZkbGevugIOX_9gHAtARpV6WaFA4Vvjnq8X9wPgqjWNCQRupadhTPz0JAsa-wy5vXQjsFlXAn43mDPpMfna5Ab3F5pS4yDwkbX6nRn7XBxH1SnnNJRFholQZw\"");
        sbJws.append("    },");
        sbJws.append("    { ");
        sbJws.append("      \"protected\": \"eyJhbGciOiJFUzI1NiIsImtpZCI6Im15RWNLZXkifQ\",");
        sbJws.append("      \"signature\": \"1OQtaT3pgZmkDxvlfghvxL_8kX16WIen6u1MadEq1pA4qytA0--_EwZDNk00GDPWFpoJtKznibMZzLOg_UhHIw\"");
        sbJws.append("    },");
        sbJws.append("    { ");
        sbJws.append("      \"protected\": \"eyJhbGciOiJIUzI1NiIsImtpZCI6Im15TWFjS2V5In0\",");
        sbJws.append("      \"signature\": \"YY8yVjmJJfy7YJOn3uUydG8WCY2PEuCvOLil5Ks5lnw\"");
        sbJws.append("    }");
        sbJws.append("  ]");
        sbJws.append("}");

        Jws jws = new Jws();

        try {
            jws.loadJwsSb(sbJws);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // The payload is easily accessible:
        System.out.println("Payload: " + jws.getPayload("utf-8"));

        StringBuilder sbKeyId = new StringBuilder();
        boolean bCaseSensitive = false;

        JsonObject protHeader = new JsonObject();
        int numSignatures = jws.getNumSignatures();
        int i = 0;
        while (i < numSignatures) {
            try {
                jws.getProtectedH(i, protHeader);
            } catch (ChilkatException e) {
                System.out.println(e.getLastErrorText());
                return;
            }

            System.out.println("--------------------------");
            System.out.println(i + ": ");

            // Get the protected header.
            protHeader.setEmitCompact(false);
            System.out.println(protHeader.emit());

            // Get the key ID ("kid") member.

            // Note: In this example, the "kid" values are contained in the protected headers.
            // They could've just as easily been located in unprotected headers.  In that case,
            // we would've called GetUnprotectedH instead of GetProtectedH(i).

            sbKeyId.clear();
            sbKeyId.append(protHeader.stringOf("kid"));

            // Set the key based on key ID.
            if (sbKeyId.contentsEqual("myRsaKey", bCaseSensitive)) {
                jws.setPublicKey(i, rsaKey);
            }

            if (sbKeyId.contentsEqual("myEcKey", bCaseSensitive)) {
                jws.setPublicKey(i, eccKey);
            }

            if (sbKeyId.contentsEqual("myMacKey", bCaseSensitive)) {
                jws.setMacKey(i, hmacKey, "base64url");
            }

            // Validate this signature.
            int v = jws.validate(i);
            if (v < 0) {
                // Perhaps Chilkat was not unlocked or the trial expired..
                System.out.println("Validate failed for some other reason.");
                System.out.println(jws.getLastErrorText());
            } else {
                if (v == 0) {
                    System.out.println("Invalid signature.  The key was incorrect, the JWS was invalid, or both.");
                } else {
                    System.out.println("Signature validated.");
                }
            }

            i = i + 1;
        }

        // The output of this program is:

        //     Payload: In our village, folks say God crumbles up the old moon into stars.
        //     --------------------------
        //     0:
        //     {
        //       "alg": "RS256",
        //       "kid": "myRsaKey"
        //     }
        //
        //     Signature validated.
        //     --------------------------
        //     1:
        //     {
        //       "alg": "ES256",
        //       "kid": "myEcKey"
        //     }
        //
        //     Signature validated.
        //     --------------------------
        //     2:
        //     {
        //       "alg": "HS256",
        //       "kid": "myMacKey"
        //     }
        //
        //     Signature validated.
    }
}