org.keycloak.jose.jwk.JWKParser Maven / Gradle / Ivy
/*
* Copyright 2016 Red Hat, Inc. and/or its affiliates
* and other contributors as indicated by the @author tags.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.keycloak.jose.jwk;
import org.bouncycastle.jce.ECNamedCurveTable;
import org.bouncycastle.jce.spec.ECNamedCurveParameterSpec;
import org.bouncycastle.jce.spec.ECNamedCurveSpec;
import org.keycloak.common.util.Base64Url;
import org.keycloak.crypto.KeyType;
import org.keycloak.util.JsonSerialization;
import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.PublicKey;
import java.security.spec.ECPoint;
import java.security.spec.ECPublicKeySpec;
import java.security.spec.RSAPublicKeySpec;
/**
* @author Stian Thorgersen
*/
public class JWKParser {
private JWK jwk;
private JWKParser() {
}
public JWKParser(JWK jwk) {
this.jwk = jwk;
}
public static JWKParser create() {
return new JWKParser();
}
public static JWKParser create(JWK jwk) {
return new JWKParser(jwk);
}
public JWKParser parse(String jwk) {
try {
this.jwk = JsonSerialization.mapper.readValue(jwk, JWK.class);
return this;
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public JWK getJwk() {
return jwk;
}
public PublicKey toPublicKey() {
String keyType = jwk.getKeyType();
if (keyType.equals(KeyType.RSA)) {
return createRSAPublicKey();
} else if (keyType.equals(KeyType.EC)) {
return createECPublicKey();
} else {
throw new RuntimeException("Unsupported keyType " + keyType);
}
}
private PublicKey createECPublicKey() {
String crv = (String) jwk.getOtherClaims().get(ECPublicJWK.CRV);
BigInteger x = new BigInteger(1, Base64Url.decode((String) jwk.getOtherClaims().get(ECPublicJWK.X)));
BigInteger y = new BigInteger(1, Base64Url.decode((String) jwk.getOtherClaims().get(ECPublicJWK.Y)));
String name;
switch (crv) {
case "P-256" :
name = "secp256r1";
break;
case "P-384" :
name = "secp384r1";
break;
case "P-521" :
name = "secp521r1";
break;
default :
throw new RuntimeException("Unsupported curve");
}
try {
ECNamedCurveParameterSpec spec = ECNamedCurveTable.getParameterSpec(name);
ECNamedCurveSpec params = new ECNamedCurveSpec("prime256v1", spec.getCurve(), spec.getG(), spec.getN());
ECPoint point = new ECPoint(x, y);
ECPublicKeySpec pubKeySpec = new ECPublicKeySpec(point, params);
KeyFactory kf = KeyFactory.getInstance("ECDSA");
return kf.generatePublic(pubKeySpec);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
private PublicKey createRSAPublicKey() {
BigInteger modulus = new BigInteger(1, Base64Url.decode(jwk.getOtherClaims().get(RSAPublicJWK.MODULUS).toString()));
BigInteger publicExponent = new BigInteger(1, Base64Url.decode(jwk.getOtherClaims().get(RSAPublicJWK.PUBLIC_EXPONENT).toString()));
try {
KeyFactory kf = KeyFactory.getInstance("RSA");
return kf.generatePublic(new RSAPublicKeySpec(modulus, publicExponent));
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public boolean isKeyTypeSupported(String keyType) {
return (RSAPublicJWK.RSA.equals(keyType) || ECPublicJWK.EC.equals(keyType));
}
}