protected void verifyRequest(final AuthnRequest request, final SAML2MessageContext context) {
        // Verify endpoint requested in the original request
        IndexedEndpoint assertionConsumerService = (AssertionConsumerService) context.
            getSAMLEndpointContext()
            .getEndpoint();
        if (request.getAssertionConsumerServiceIndex() != null) {
            if (!request.getAssertionConsumerServiceIndex().equals(assertionConsumerService.getIndex())) {
                logger.warn("Response was received at a different endpoint index than was requested");
            }
        } else {
            val requestedResponseURL = request.getAssertionConsumerServiceURL();
            val requestedBinding = request.getProtocolBinding();
            if (requestedResponseURL != null) {
                final String responseLocation;
                if (assertionConsumerService.getResponseLocation() != null) {
                    responseLocation = assertionConsumerService.getResponseLocation();
                } else {
                    responseLocation = assertionConsumerService.getLocation();
                }
                if (!requestedResponseURL.equals(responseLocation)) {
                    logger.warn("Response was received at a different endpoint URL {} than was requested {}",
                        responseLocation, requestedResponseURL);
                }
            }
            if (requestedBinding != null && !requestedBinding.equals(context.getSAMLBindingContext().getBindingUri())) {
                logger.warn("Response was received using a different binding {} than was requested {}",
                    context.getSAMLBindingContext().getBindingUri(), requestedBinding);
            }
        }
    }
<p>verifyRequest.</p>

@param request a {@link AuthnRequest} object
@param context a {@link SAML2MessageContext} object
pac4j-saml/src/main/java/org/pac4j/saml/sso/impl/SAML2AuthnResponseValidator.java