RocketChat/Rocket.Chat

import xmldom from '@xmldom/xmldom';

import type { IServiceProviderOptions } from '../../definition/IServiceProviderOptions';
import type { ILogoutResponseValidateCallback } from '../../definition/callbacks';
import { SAMLUtils } from '../Utils';

export class LogoutResponseParser {
    serviceProviderOptions: IServiceProviderOptions;

    constructor(serviceProviderOptions: IServiceProviderOptions) {
        this.serviceProviderOptions = serviceProviderOptions;
    }

    public async validate(xmlString: string, callback: ILogoutResponseValidateCallback): Promise<void> {
        SAMLUtils.log(`LogoutResponse: ${xmlString}`);

        const doc = new xmldom.DOMParser().parseFromString(xmlString, 'text/xml');
        if (!doc) {
            return callback('No Doc Found');
        }

        const response = doc.getElementsByTagNameNS('urn:oasis:names:tc:SAML:2.0:protocol', 'LogoutResponse')[0];
        if (!response) {
            return callback('No Response Found', null);
        }

        // TBD. Check if this msg corresponds to one we sent
        let inResponseTo;
        try {
            inResponseTo = response.getAttribute('InResponseTo');
            SAMLUtils.log(`In Response to: ${inResponseTo}`);
        } catch (e) {
            SAMLUtils.log(`Caught error: ${e}`);
            const msg = doc.getElementsByTagNameNS('urn:oasis:names:tc:SAML:2.0:protocol', 'StatusMessage');
            SAMLUtils.log(`Unexpected msg from IDP. Does your session still exist at IDP? Idp returned: \n ${msg}`);
        }

        if (!inResponseTo) {
            return callback('Unexpected Response from IDP', null);
        }

        const statusValidateObj = SAMLUtils.validateStatus(doc);
        if (!statusValidateObj.success) {
            return callback('Error. Logout not confirmed by IDP', null);
        }

        return callback(null, inResponseTo);
    }
}