如何在 Java 中验证 Azure AD JWT 令牌？

问：

我有一个使用 Msal 库获取的 Azure AD JWT 令牌，但当我尝试验证此令牌时，会出现以下问题：

客户端：SharePoint Web 部件

 const config = {
     auth: {
         clientId: "xxxxx",
         authority: "https://login.microsoftonline.com/yyyyyy"
     }
 };

 const myMSALObj = new UserAgentApplication(config);

 let accessTokenRequest = {
     scopes: ["user.read"],
     loginHint: this.context.pageContext.user.loginName,
     extraQueryParameters: {domain_hint: 'organizations'}
 }

 myMSALObj.acquireTokenSilent(accessTokenRequest).then(
  function(accessTokenResponse) { 
  // Acquire token silent success 
  let accessToken = accessTokenResponse.accessToken;

我正在尝试从以下位置检索公钥：https://login.microsoftonline.com/tenant-id/.well-known/openid-configuration 但是使用此公钥，我永远无法重定向到：https://login.microsoftonline.com/common/discovery/keys

在这种情况下，有没有其他方法可以获取公钥？

服务器：验证

public PublicKey getPublicKeyFromParams(String e, String n){

    byte[] modulusBytes = Base64.getUrlDecoder().decode(n);

    BigInteger modulusInt = new BigInteger(1, modulusBytes);

    byte[] exponentBytes = Base64.getUrlDecoder().decode(e);

    BigInteger exponentInt = new BigInteger(1, exponentBytes);

    KeyFactory keyFactory;

    RSAPublicKeySpec publicSpec = new RSAPublicKeySpec(modulusInt, exponentInt);

        try {

            keyFactory = KeyFactory.getInstance("RSA");

            return keyFactory.generatePublic(publicSpec);

        } catch (NoSuchAlgorithmException | InvalidKeySpecException ex) {

            ex.printStackTrace();

        }

    return null;

}

@Test

public void name() throws Exception {

    String jwt = "xxxxxxx";

    KeyPair keyPair = Keys.keyPairFor(SignatureAlgorithm.RS256);

    String e = Base64.getUrlEncoder().encodeToString((((RSAPublicKeyImpl) keyPair.getPublic()).getPublicExponent()).toByteArray());

    String n = Base64.getUrlEncoder().encodeToString((((RSAPublicKeyImpl) keyPair.getPublic()).getModulus()).toByteArray());

    System.out.println("Public Key: " + Base64.getUrlEncoder().encodeToString(keyPair.getPublic().getEncoded()));

    System.out.println("Public Key Exponent: " + e);

    System.out.println("Public Key Modulus: " + n);

    String jws = Jwts.builder().setSubject("pepe").signWith(keyPair.getPrivate()).compact();

    System.out.println("Generated JWS:" + jws);

    PublicKey publicKey = getPublicKeyFromParams(e, n);

    Jwt parsedJWs = Jwts.parserBuilder().setSigningKey(publicKey).build().parse(jws);

    System.out.println("Parsed JWS: " + parsedJWs);

    publicKey = getPublicKeyFromParams(eValue, nValue);

    System.out.println("Azure PublicKey fron n-e: " + publicKey);

    CertificateFactory factory = CertificateFactory.getInstance("X.509");

    Certificate cert = factory.generateCertificate(new ByteArrayInputStream(

    DatatypeConverter.parseBase64Binary("cccccccccccccccccc")));

    publicKey = cert.getPublicKey();

    System.out.println("Azure PublicKey from x5c: " + publicKey);

    Jwt jwtParsed = Jwts.parserBuilder().setSigningKey(publicKey).build().parse(jwt);

    System.out.println(jwtParsed);

}

public static PublicKey getPublicKey(String key){

    try{

        byte[] byteKey = Base64.getDecoder().decode(key);

        X509EncodedKeySpec X509publicKey = new X509EncodedKeySpec(byteKey);

        KeyFactory kf = KeyFactory.getInstance("RSA");

        return kf.generatePublic(X509publicKey);

    }

    catch(Exception e){

        e.printStackTrace();

    }

    return null;

}