lusca

Web application security middleware.

Usage

var express = require('express'),
	app = express(),
	session = require('express-session'),
	lusca = require('lusca');

//this or other session management will be required
app.use(session({
	secret: 'abc',
	resave: true,
	saveUninitialized: true
}));

app.use(lusca({
    csrf: true,
    csp: { /* ... */},
    xframe: 'SAMEORIGIN',
    p3p: 'ABCDEF',
    hsts: {maxAge: 31536000, includeSubDomains: true, preload: true},
    xssProtection: true,
    nosniff: true,
    referrerPolicy: 'same-origin'
}));

Setting any value to false will disable it. Alternately, you can opt into methods one by one:

app.use(lusca.csrf());
app.use(lusca.csp({ /* ... */}));
app.use(lusca.xframe('SAMEORIGIN'));
app.use(lusca.p3p('ABCDEF'));
app.use(lusca.hsts({ maxAge: 31536000 }));
app.use(lusca.xssProtection(true));
app.use(lusca.nosniff());
app.use(lusca.referrerPolicy('same-origin'));

Please note that you must use express-session, cookie-session, their express 3.x alternatives, or other session object management in order to use lusca.

API

lusca.csrf(options)

• key String - Optional. The name of the CSRF token added to the model. Defaults to _csrf.
• secret String - Optional. The key to place on the session object which maps to the server side token. Defaults to _csrfSecret.
• impl Function - Optional. Custom implementation to generate a token.
• cookie String|Object - Optional. If set, a cookie with the name and/or options you provide will be set with the CSRF token. If the value is a string, it'll be used as the cookie name.
• cookie.name String - Required if cookie is an object and angular is not true. The CSRF cookie name to set.
• cookie.options Object - Optional. A valid Express cookie options object.
• angular Boolean - Optional. Shorthand setting to set lusca up to use the default settings for CSRF validation according to the AngularJS docs. Can be used with cookie.options.

Enables Cross Site Request Forgery (CSRF) headers.

If enabled, the CSRF token must be in the payload when modifying data or you will receive a 403 Forbidden. To send the token you'll need to echo back the _csrf value you received from the previous request.

Furthermore, parsers must be registered before lusca.

lusca.csp(options)

• options.policy String, Object, or an Array - Object definition of policy. Valid policies examples include:
  • {"default-src": "*"}
  • "referrer no-referrer"
  • [{ "img-src": "'self' http:" }, "block-all-mixed-content"]
• options.reportOnly Boolean - Enable report only mode.
• options.reportUri String - URI where to send the report data
• options.styleNonce Boolean - Enable nonce for inline style-src, access from req.locals.nonce
• options.scriptNonce Boolean - Enable nonce for inline script-src, access from req.locals.nonce

Enables Content Security Policy (CSP) headers.

Example Options

// Everything but images can only come from own domain (excluding subdomains)
{
  policy: {
    'default-src': '\'self\'',
    'img-src': '*'
  }
}

See the MDN CSP usage page for more information on available policy options.

lusca.xframe(value)

• value String - Required. The value for the header, e.g. DENY, SAMEORIGIN or ALLOW-FROM uri.

Enables X-FRAME-OPTIONS headers to help prevent Clickjacking.

lusca.p3p(value)

• value String - Required. The compact privacy policy.

Enables Platform for Privacy Preferences Project (P3P) headers.

lusca.hsts(options)

• options.maxAge Number - Required. Number of seconds HSTS is in effect.
• options.includeSubDomains Boolean - Optional. Applies HSTS to all subdomains of the host
• options.preload Boolean - Optional. Adds preload flag

Enables HTTP Strict Transport Security for the host domain. The preload flag is required for HSTS domain submissions to Chrome's HSTS preload list.

lusca.xssProtection(options)

• options.enabled Boolean - Optional. If the header is enabled or not (see header docs). Defaults to 1.
• options.mode String - Optional. Mode to set on the header (see header docs). Defaults to block.

Enables X-XSS-Protection headers to help prevent cross site scripting (XSS) attacks in older IE browsers (IE8)

lusca.nosniff()

Enables X-Content-Type-Options header to prevent MIME-sniffing a response away from the declared content-type.

lusca.referrerPolicy(value)

• value String - Optional. The value for the header, e.g. origin, same-origin, no-referrer. Defaults to `` (empty string).

Enables Referrer-Policy header to control the Referer header.