@sap/xssec/src/util/util.js

XS Advanced Container Security API for node.js

const { X509Certificate } = require("crypto");
const InvalidClientCertificateError = require("../error/validation/InvalidClientCertificateError");
const { PEM_HEADER, PEM_FOOTER, CLIENT_CERTIFICATE_HEADER } = require("./constants");

module.exports = {
    /**
     * Escapes Regex special characters in the given string, so that the string can be used for a literal match inside a Regex.
     * Regex.escape is only a proposal at the time of writing.
     * The source of this code is https://github.com/tc39/proposal-regex-escaping/blob/main/polyfill.js 
     */
    escapeStringForRegex(s) {
        return String(s).replace(/[\\^$*+?.()|[\]{}]/g, '\\$&');
    },

    /**
     * Creates a string cache key from the given key-value pairs, ignoring keys with null or undefined values.
     * @param {object} parts
     * @returns a cache key in string format, e.g. app_tid:foo:client_id:bar:azp:baz
     */
    createCacheKey(parts = {}) {
        return Object.entries(parts)
            .filter(([value]) => value != null)
            .map(([key, value]) => `${key}=${value}`)
            .join("|");
    },

    parsePemCertificate(pem) {
        // restore new lines
        pem = pem.replaceAll("\\n", "\n");

        // add PEM header and footer
        if (!pem.startsWith(PEM_HEADER)) pem = `${PEM_HEADER}\n${pem}`;
        if (!pem.endsWith(PEM_FOOTER)) pem = `${pem}\n${PEM_FOOTER}`;

        try {
            return new X509Certificate(pem);
        } catch (error) {
            throw new InvalidClientCertificateError(pem, error);
        }
    },

    shrinkRequestOptionsForLog(request) {
        const maskedRequest = {...request};
        maskedRequest.headers = {...request.headers};
        
        if(maskedRequest.agent) {
            maskedRequest.agent = "<agent>";
        }

        if(maskedRequest.headers?.[CLIENT_CERTIFICATE_HEADER]) {
            maskedRequest.headers[CLIENT_CERTIFICATE_HEADER] = "<clientCertificatePem>"
        }

        return maskedRequest;
    }
};