private Assertion buildSAMLAssertion(
      SAMLSSOAuthnReqDTO authReqDTO, DateTime notOnOrAfter, String sessionId)
      throws IdentityException {
    try {
      DateTime currentTime = new DateTime();
      Assertion samlAssertion = new AssertionBuilder().buildObject();
      samlAssertion.setID(SAMLSSOUtil.createID());
      samlAssertion.setVersion(SAMLVersion.VERSION_20);
      samlAssertion.setIssuer(SAMLSSOUtil.getIssuer());
      samlAssertion.setIssueInstant(currentTime);
      Subject subject = new SubjectBuilder().buildObject();

      NameID nameId = new NameIDBuilder().buildObject();
      if (authReqDTO.getUseFullyQualifiedUsernameAsSubject()) {
        nameId.setValue(authReqDTO.getUsername());
        nameId.setFormat(NameIdentifier.EMAIL);
      } else {
        nameId.setValue(MultitenantUtils.getTenantAwareUsername(authReqDTO.getUsername()));
        nameId.setFormat(authReqDTO.getNameIDFormat());
      }

      subject.setNameID(nameId);

      SubjectConfirmation subjectConfirmation = new SubjectConfirmationBuilder().buildObject();
      subjectConfirmation.setMethod(SAMLSSOConstants.SUBJECT_CONFIRM_BEARER);

      SubjectConfirmationData scData = new SubjectConfirmationDataBuilder().buildObject();
      scData.setRecipient(authReqDTO.getAssertionConsumerURL());
      scData.setNotOnOrAfter(notOnOrAfter);
      scData.setInResponseTo(authReqDTO.getId());
      subjectConfirmation.setSubjectConfirmationData(scData);

      subject.getSubjectConfirmations().add(subjectConfirmation);

      samlAssertion.setSubject(subject);

      AuthnStatement authStmt = new AuthnStatementBuilder().buildObject();
      authStmt.setAuthnInstant(new DateTime());

      AuthnContext authContext = new AuthnContextBuilder().buildObject();
      AuthnContextClassRef authCtxClassRef = new AuthnContextClassRefBuilder().buildObject();
      authCtxClassRef.setAuthnContextClassRef(AuthnContext.PASSWORD_AUTHN_CTX);
      authContext.setAuthnContextClassRef(authCtxClassRef);
      authStmt.setAuthnContext(authContext);
      if (authReqDTO.isDoSingleLogout()) {
        authStmt.setSessionIndex(sessionId);
      }
      samlAssertion.getAuthnStatements().add(authStmt);

      /*
       * If <AttributeConsumingServiceIndex> element is in the
       * <AuthnRequest> and
       * according to the spec 2.0 the subject MUST be in the assertion
       */
      Map<String, String> claims = SAMLSSOUtil.getAttributes(authReqDTO);
      if (claims != null) {
        samlAssertion.getAttributeStatements().add(buildAttributeStatement(claims));
      }

      AudienceRestriction audienceRestriction = new AudienceRestrictionBuilder().buildObject();
      Audience issuerAudience = new AudienceBuilder().buildObject();
      issuerAudience.setAudienceURI(authReqDTO.getIssuer());
      audienceRestriction.getAudiences().add(issuerAudience);
      if (authReqDTO.getRequestedAudiences() != null) {
        for (String requestedAudience : authReqDTO.getRequestedAudiences()) {
          Audience audience = new AudienceBuilder().buildObject();
          audience.setAudienceURI(requestedAudience);
          audienceRestriction.getAudiences().add(audience);
        }
      }
      Conditions conditions = new ConditionsBuilder().buildObject();
      conditions.setNotBefore(currentTime);
      conditions.setNotOnOrAfter(notOnOrAfter);
      conditions.getAudienceRestrictions().add(audienceRestriction);
      samlAssertion.setConditions(conditions);

      if (authReqDTO.getDoSignAssertions()) {
        SAMLSSOUtil.setSignature(
            samlAssertion,
            XMLSignature.ALGO_ID_SIGNATURE_RSA,
            new SignKeyDataHolder(authReqDTO.getUsername()));
      }

      return samlAssertion;
    } catch (Exception e) {
      log.error("Error when reading claim values for generating SAML Response", e);
      throw new IdentityException(
          "Error when reading claim values for generating SAML Response", e);
    }
  }
  private static List<AttributeStatement> validateAssertion(
      Assertion samlAssertion,
      SignatureTrustEngine sigTrustEngine,
      String myURI,
      MessageReplayRule replayRule,
      VerifySignatureType verifySignature,
      boolean responseSignatureVerified)
      throws SAMLValidationException {
    if (logger.isDebugEnabled()) {
      logger.debug(
          "validateAndExtractContext(Assertion, String, SignatureTrustEngine, String, MessageReplayRule, VerifySignatureType) - start"); //$NON-NLS-1$
    }

    // Check the replay attack
    if (replayRule != null) {
      BasicSAMLMessageContext messageContext = new BasicSAMLMessageContext();
      // messageContext.setInboundMessage(samlResponse);
      if (samlAssertion.getIssuer() != null)
        messageContext.setInboundMessageIssuer(samlAssertion.getIssuer().getValue());
      messageContext.setInboundSAMLMessageId(samlAssertion.getID());

      try {
        replayRule.evaluate(messageContext);
      } catch (SecurityPolicyException e) {
        logger.error(
            "validateAndExtractContext(Assertion, String, SignatureTrustEngine, String, MessageReplayRule, VerifySignatureType)",
            e); //$NON-NLS-1$

        throw createSAMLValidationException("Possible Replay Attack for Assertion", false, e);
      }
    }

    if (verifySignature != VerifySignatureType.never) {
      Signature signature = samlAssertion.getSignature();
      if (signature == null) {
        if (verifySignature == VerifySignatureType.force && !responseSignatureVerified) {
          throw createSAMLValidationException("Signature does exist in Assertion", true);
        }
      } else {
        verifySignature(signature, samlAssertion.getIssuer().getValue(), sigTrustEngine);
      }
    }
    DateTime dt = new DateTime();

    // get subject (code below only processes first Subject confirmation)
    Subject subject = samlAssertion.getSubject();
    SubjectSchemaValidator subjectSchemaValidator = new SubjectSchemaValidator();
    try {
      subjectSchemaValidator.validate(subject);
    } catch (ValidationException e) {
      logger.error(
          "validateAndExtractContext(Assertion, String, SignatureTrustEngine, String, MessageReplayRule, VerifySignatureType)",
          e); //$NON-NLS-1$

      throw createSAMLValidationException("Subject validation failed: " + e.getMessage(), true, e);
    }
    List<SubjectConfirmation> subjectConfirmations = subject.getSubjectConfirmations();
    for (SubjectConfirmation subjectConfirmation : subjectConfirmations) {
      SubjectConfirmationSchemaValidator subjectConfirmationSchemaValidator =
          new SubjectConfirmationSchemaValidator();
      try {
        subjectConfirmationSchemaValidator.validate(subjectConfirmation);
      } catch (ValidationException e) {
        logger.error(
            "validateAndExtractContext(Assertion, String, SignatureTrustEngine, String, MessageReplayRule, VerifySignatureType)",
            e); //$NON-NLS-1$

        throw createSAMLValidationException(
            "Subject Confirmation validation failed: " + e.getMessage(), true, e);
      }
      SubjectConfirmationData subjectConfirmationData =
          subjectConfirmation.getSubjectConfirmationData();
      try {
        subjectConfirmationSchemaValidator.validate(subjectConfirmation);
      } catch (ValidationException e) {
        logger.error(
            "validateAndExtractContext(Assertion, String, SignatureTrustEngine, String, MessageReplayRule, VerifySignatureType)",
            e); //$NON-NLS-1$

        throw createSAMLValidationException(
            "Subject Confirmation validation failed: " + e.getMessage(), true, e);
      }

      // verify the validity of time using clock skew, subjectConfirmationData.getNotBefore() and
      // subjectConfirmationData.getNotOnOrAfter()@
      DateTime notBefore = subjectConfirmationData.getNotBefore();
      DateTime notAfter = subjectConfirmationData.getNotOnOrAfter();

      if (notBefore != null && dt.isBefore(notBefore)) {
        throw createSAMLValidationException("Subject confirmation expired.", true);
      }

      if (notAfter != null && (dt.equals(notAfter) || dt.isAfter(notAfter))) {
        throw createSAMLValidationException("Subject confirmation expired.", true);
      }
    }

    //		 validate conditions
    Conditions conditions = samlAssertion.getConditions();

    // Validate the spec

    ConditionsSpecValidator conditionValidator = new ConditionsSpecValidator();
    try {
      conditionValidator.validate(conditions);
    } catch (ValidationException e) {
      logger.error(
          "validateAndExtractContext(Assertion, String, SignatureTrustEngine, String, MessageReplayRule, VerifySignatureType)",
          e); //$NON-NLS-1$

      throw createSAMLValidationException("Condition Validity Failed.", true, e);
    }

    // verify the validity of time using clock skew, conditions.getNotBefore() and
    // conditions.getNotOnOrAfter()@
    DateTime notBefore = conditions.getNotBefore();
    DateTime notAfter = conditions.getNotOnOrAfter();
    if (notBefore != null && dt.isBefore(notBefore)) {
      throw createSAMLValidationException("Assertion expired.", true);
    }

    if (notAfter != null && (dt.equals(notAfter) || dt.isAfter(notAfter))) {
      throw createSAMLValidationException("Assertion expired.", true);
    }

    for (Condition condition : conditions.getConditions()) {
      if (condition instanceof AudienceRestriction) {
        if (myURI != null && myURI.length() > 0) {
          boolean audiencePresent = false;
          boolean iAmOneOfTheAudience = false;
          AudienceRestriction audienceRestriction = (AudienceRestriction) condition;
          for (Audience audience : audienceRestriction.getAudiences()) {
            audiencePresent = true;
            String audienceURI = audience.getAudienceURI();
            if (myURI.equals(audienceURI)) {
              iAmOneOfTheAudience = true;
              break;
            }
          }
          if (!(audiencePresent && iAmOneOfTheAudience)) {
            throw createSAMLValidationException(
                "None of the audience is intended for me: " + myURI, false);
          }
        }
      }
    }

    List<AttributeStatement> asList = samlAssertion.getAttributeStatements();

    if (logger.isDebugEnabled()) {
      logger.debug(
          "validateAndExtractContext(Assertion, String, SignatureTrustEngine, String, MessageReplayRule, VerifySignatureType) - end"); //$NON-NLS-1$
    }
    return asList;
  }