code: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements. See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership. The ASF licenses this file
   * to you 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.apache.cxf.ws.security.wss4j;
  
  import java.security.Principal;
  import java.security.PublicKey;
  import java.security.cert.Certificate;
  import java.security.cert.X509Certificate;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.logging.Logger;
  
  import org.w3c.dom.Element;
  
  import org.apache.cxf.common.logging.LogUtils;
  import org.apache.cxf.helpers.CastUtils;
  import org.apache.cxf.message.Message;
  import org.apache.cxf.security.transport.TLSSessionInfo;
  import org.apache.ws.security.WSConstants;
  import org.apache.ws.security.WSDataRef;
  import org.apache.ws.security.WSDerivedKeyTokenPrincipal;
  import org.apache.ws.security.WSSecurityEngineResult;
  import org.apache.ws.security.WSSecurityException;
  import org.apache.ws.security.saml.SAMLKeyInfo;
  import org.apache.ws.security.saml.ext.AssertionWrapper;
  import org.apache.ws.security.saml.ext.OpenSAMLUtil;
  import org.apache.ws.security.util.WSSecurityUtil;
  import org.opensaml.common.SAMLVersion;
  import org.opensaml.xml.XMLObject;
  
  /**
   * internal SAMLUtils to avoid direct reference to opensaml from WSS4J interceptors.
   */
  public final class SAMLUtils {
      
      private static final Logger LOG = LogUtils.getL7dLogger(SAMLUtils.class);
      
      private SAMLUtils() {
      }
      
      public static List<String> parseRolesInAssertion(Object assertion, String roleAttributeName) {
          if (((AssertionWrapper) assertion).getSamlVersion().equals(SAMLVersion.VERSION_20)) {
              return parseRolesInAssertion(((AssertionWrapper)assertion).getSaml2(), roleAttributeName);
          } else {
              return parseRolesInAssertion(((AssertionWrapper)assertion).getSaml1(), roleAttributeName);
          }
      }
      
      public static String getIssuer(Object assertion) {
          return ((AssertionWrapper)assertion).getIssuerString();
      }
      
      public static Element getAssertionElement(Object assertion) {
          return ((AssertionWrapper)assertion).getElement();
      }
      
      //
      // these methods are moved from previous WSS4JInInterceptor
      //
      private static List<String> parseRolesInAssertion(org.opensaml.saml1.core.Assertion assertion,
              String roleAttributeName) {
          List<org.opensaml.saml1.core.AttributeStatement> attributeStatements = 
              assertion.getAttributeStatements();
          if (attributeStatements == null || attributeStatements.isEmpty()) {
              return null;
          }
          List<String> roles = new ArrayList<String>();
          
          for (org.opensaml.saml1.core.AttributeStatement statement : attributeStatements) {
              
              List<org.opensaml.saml1.core.Attribute> attributes = statement.getAttributes();
              for (org.opensaml.saml1.core.Attribute attribute : attributes) {
                  
                  if (attribute.getAttributeName().equals(roleAttributeName)) {
                      for (XMLObject attributeValue : attribute.getAttributeValues()) {
                          Element attributeValueElement = attributeValue.getDOM();
                          String value = attributeValueElement.getTextContent();
                          roles.add(value);                    
                      }
                      if (attribute.getAttributeValues().size() > 1) {
  //                        Don't search for other attributes with the same name if                         
  //                        <saml:Attribute xmlns:saml="urn:oasis:names:tc:SAML:1.0:assertion"
  //                             AttributeNamespace="http://schemas.xmlsoap.org/claims" AttributeName="roles">
  //                        <saml:AttributeValue>Value1</saml:AttributeValue>
  //                        <saml:AttributeValue>Value2</saml:AttributeValue>
  //                        </saml:Attribute>
                          break;
                      }
                  }
                  
              }
          }
          return Collections.unmodifiableList(roles);
      }
      
  
      private static List<String> parseRolesInAssertion(org.opensaml.saml2.core.Assertion assertion,
              String roleAttributeName) {
          List<org.opensaml.saml2.core.AttributeStatement> attributeStatements = 
              assertion.getAttributeStatements();
          if (attributeStatements == null || attributeStatements.isEmpty()) {
              return null;
          }
          List<String> roles = new ArrayList<String>();
          
          for (org.opensaml.saml2.core.AttributeStatement statement : attributeStatements) {
              
              List<org.opensaml.saml2.core.Attribute> attributes = statement.getAttributes();
              for (org.opensaml.saml2.core.Attribute attribute : attributes) {
                  
                  if (attribute.getName().equals(roleAttributeName)) {
                      for (XMLObject attributeValue : attribute.getAttributeValues()) {
                          Element attributeValueElement = attributeValue.getDOM();
                          String value = attributeValueElement.getTextContent();
                          roles.add(value);                    
                      }
                      if (attribute.getAttributeValues().size() > 1) {
  //                        Don't search for other attributes with the same name if                         
  //                        <saml:Attribute xmlns:saml="urn:oasis:names:tc:SAML:1.0:assertion"
  //                             AttributeNamespace="http://schemas.xmlsoap.org/claims" AttributeName="roles">
  //                        <saml:AttributeValue>Value1</saml:AttributeValue>
  //                        <saml:AttributeValue>Value2</saml:AttributeValue>
  //                        </saml:Attribute>
                          break;
                      }
                  }
                  
              }
          }
          return Collections.unmodifiableList(roles);
      }
      
      public static void validateSAMLResults(
          List<WSSecurityEngineResult> results,
          Message message,
          Element body
      ) throws WSSecurityException {
          List<WSSecurityEngineResult> samlResults = new ArrayList<WSSecurityEngineResult>();
          WSSecurityUtil.fetchAllActionResults(results, WSConstants.ST_SIGNED, samlResults);
          WSSecurityUtil.fetchAllActionResults(results, WSConstants.ST_UNSIGNED, samlResults);
          
          if (samlResults.isEmpty()) {
              return;
          }
          
          List<WSSecurityEngineResult> signedResults = new ArrayList<WSSecurityEngineResult>();
          WSSecurityUtil.fetchAllActionResults(results, WSConstants.SIGN, signedResults);
          WSSecurityUtil.fetchAllActionResults(results, WSConstants.UT_SIGN, signedResults);
          
          for (WSSecurityEngineResult samlResult : samlResults) {
              AssertionWrapper assertionWrapper = 
                  (AssertionWrapper)samlResult.get(WSSecurityEngineResult.TAG_SAML_ASSERTION);
              
              TLSSessionInfo tlsInfo = message.get(TLSSessionInfo.class);
              Certificate[] tlsCerts = null;
              if (tlsInfo != null) {
                  tlsCerts = tlsInfo.getPeerCertificates();
              }
              if (!SAMLUtils.checkHolderOfKey(assertionWrapper, signedResults, tlsCerts)) {
                  LOG.warning("Assertion fails holder-of-key requirements");
                  throw new WSSecurityException(WSSecurityException.INVALID_SECURITY);
              }
              if (!SAMLUtils.checkSenderVouches(assertionWrapper, tlsCerts, body, signedResults)) {
                  LOG.warning("Assertion fails sender-vouches requirements");
                  throw new WSSecurityException(WSSecurityException.INVALID_SECURITY);
              }
          }
          
      }
      
      /**
       * Check the holder-of-key requirements against the received assertion. The subject
       * credential of the SAML Assertion must have been used to sign some portion of
       * the message, thus showing proof-of-possession of the private/secret key. Alternatively,
       * the subject credential of the SAML Assertion must match a client certificate credential
       * when 2-way TLS is used.
       * @param assertionWrapper the SAML Assertion wrapper object
       * @param signedResults a list of all of the signed results
       */
      public static boolean checkHolderOfKey(
          AssertionWrapper assertionWrapper,
          List<WSSecurityEngineResult> signedResults,
          Certificate[] tlsCerts
      ) {
          List<String> confirmationMethods = assertionWrapper.getConfirmationMethods();
          for (String confirmationMethod : confirmationMethods) {
              if (OpenSAMLUtil.isMethodHolderOfKey(confirmationMethod)) {
                  if (tlsCerts == null && (signedResults == null || signedResults.isEmpty())) {
                      return false;
                  }
                  SAMLKeyInfo subjectKeyInfo = assertionWrapper.getSubjectKeyInfo();
                  if (!compareCredentials(subjectKeyInfo, signedResults, tlsCerts)) {
                      return false;
                  }
              }
          }
          return true;
      }
  
      /**
       * Compare the credentials of the assertion to the credentials used in 2-way TLS or those
       * used to verify signatures.
       * Return true on a match
       * @param subjectKeyInfo the SAMLKeyInfo object
       * @param signedResults a list of all of the signed results
       * @return true if the credentials of the assertion were used to verify a signature
       */
      public static boolean compareCredentials(
          SAMLKeyInfo subjectKeyInfo,
          List<WSSecurityEngineResult> signedResults,
          Certificate[] tlsCerts
      ) {
          X509Certificate[] subjectCerts = subjectKeyInfo.getCerts();
          PublicKey subjectPublicKey = subjectKeyInfo.getPublicKey();
          byte[] subjectSecretKey = subjectKeyInfo.getSecret();
          
          //
          // Try to match the TLS certs first
          //
          if (tlsCerts != null && tlsCerts.length > 0 && subjectCerts != null 
              && subjectCerts.length > 0 && tlsCerts[0].equals(subjectCerts[0])) {
              return true;
          } else if (tlsCerts != null && tlsCerts.length > 0 && subjectPublicKey != null
              && tlsCerts[0].getPublicKey().equals(subjectPublicKey)) {
              return true;
          }
          
          //
          // Now try the message-level signatures
          //
          for (WSSecurityEngineResult signedResult : signedResults) {
              X509Certificate[] certs =
                  (X509Certificate[])signedResult.get(WSSecurityEngineResult.TAG_X509_CERTIFICATES);
              PublicKey publicKey =
                  (PublicKey)signedResult.get(WSSecurityEngineResult.TAG_PUBLIC_KEY);
              byte[] secretKey =
                  (byte[])signedResult.get(WSSecurityEngineResult.TAG_SECRET);
              if (certs != null && certs.length > 0 && subjectCerts != null
                  && subjectCerts.length > 0 && certs[0].equals(subjectCerts[0])) {
                  return true;
              }
              if (publicKey != null && publicKey.equals(subjectPublicKey)) {
                  return true;
              }
              if (checkSecretKey(secretKey, subjectSecretKey, signedResult)) {
                  return true;
              }
          }
          return false;
      }
      
      private static boolean checkSecretKey(
          byte[] secretKey,
          byte[] subjectSecretKey,
          WSSecurityEngineResult signedResult
      ) {
          if (secretKey != null && subjectSecretKey != null) {
              if (Arrays.equals(secretKey, subjectSecretKey)) {
                  return true;
              } else {
                  Principal principal =
                      (Principal)signedResult.get(WSSecurityEngineResult.TAG_PRINCIPAL);
                  if (principal instanceof WSDerivedKeyTokenPrincipal) {
                      secretKey = ((WSDerivedKeyTokenPrincipal)principal).getSecret();
                      if (Arrays.equals(secretKey, subjectSecretKey)) {
                          return true;
                      }
                  }
              }
          }
          return false;
      }
      
      /**
       * Check the sender-vouches requirements against the received assertion. The SAML
       * Assertion and the SOAP Body must be signed by the same signature.
       */
      public static boolean checkSenderVouches(
          AssertionWrapper assertionWrapper,
          Certificate[] tlsCerts,
          Element body,
          List<WSSecurityEngineResult> signed
      ) {
          //
          // If we have a 2-way TLS connection, then we don't have to check that the
          // assertion + SOAP body are signed
          //
          if (tlsCerts != null && tlsCerts.length > 0) {
              return true;
          }
          List<String> confirmationMethods = assertionWrapper.getConfirmationMethods();
          for (String confirmationMethod : confirmationMethods) {
              if (OpenSAMLUtil.isMethodSenderVouches(confirmationMethod)) {
                  if (signed == null || signed.isEmpty()) {
                      return false;
                  }
                  if (!checkAssertionAndBodyAreSigned(assertionWrapper, body, signed)) {
                      return false;
                  }
              }
          }
          return true;
      }
  
      /**
       * Return true if there is a signature which references the Assertion and the SOAP Body.
       * @param assertionWrapper the AssertionWrapper object
       * @param body The SOAP body
       * @param signed The List of signed results
       * @return true if there is a signature which references the Assertion and the SOAP Body.
       */
      private static boolean checkAssertionAndBodyAreSigned(
          AssertionWrapper assertionWrapper,
          Element body,
          List<WSSecurityEngineResult> signed
      ) {
          for (WSSecurityEngineResult signedResult : signed) {
              List<WSDataRef> sl =
                  CastUtils.cast((List<?>)signedResult.get(
                      WSSecurityEngineResult.TAG_DATA_REF_URIS
                  ));
              boolean assertionIsSigned = false;
              boolean bodyIsSigned = false;
              if (sl != null) {
                  for (WSDataRef dataRef : sl) {
                      Element se = dataRef.getProtectedElement();
                      if (se == assertionWrapper.getElement()) {
                          assertionIsSigned = true;
                      }
                      if (se == body) {
                          bodyIsSigned = true;
                      }
                      if (assertionIsSigned && bodyIsSigned) {
                          return true;
                      }
                  }
              }
          }
          return false;
      }
  
  }
  