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// SPDX-FileCopyrightText: 2026 Progmasoft <support@progmasoft.com>
// SPDX-License-Identifier: AGPL-3.0-or-later WITH AdditionRef-Progmasoft-Patent-Grant-1.1
/** The request header that carries the nonce of a page to its layout. */
export const nonceHeader = "x-nonce";
/**
* A fresh nonce for one response: 128 random bits in base64.
*
* @returns The nonce.
*/
export function createNonce(): string {
return btoa(
String.fromCharCode(...crypto.getRandomValues(new Uint8Array(16))),
);
}
/**
* The Content-Security-Policy of a page. Next marks its own inline scripts
* with the nonce when it reads this policy from the request; the theme
* bootstrap of the layout carries it too.
*
* Cloudflare adds its Web Analytics beacon to every page, from
* static.cloudflareinsights.com, reporting to cloudflareinsights.com and to
* /cdn-cgi/rum on the same host. 'strict-dynamic' would make browsers ignore
* that host, so the policy lists hosts instead.
*
* There is no form-action: a sign-in or consent form ends in a redirect to
* another Progmasoft host or to an OAuth client, including a loopback address,
* and browsers apply form-action to those redirects.
*
* @param nonce The nonce of the response.
* @param development Whether the development server runs, which evaluates code
* for its hot reload.
* @returns The value of the header.
*/
export function contentSecurityPolicy(
nonce: string,
development: boolean,
): string {
const scripts = [
"'self'",
`'nonce-${nonce}'`,
"https://static.cloudflareinsights.com",
...(development ? ["'unsafe-eval'"] : []),
];
return [
"default-src 'self'",
`script-src ${scripts.join(" ")}`,
"style-src 'self' 'unsafe-inline'",
"img-src 'self' data:",
"font-src 'self'",
"connect-src 'self' https://cloudflareinsights.com",
"object-src 'none'",
"base-uri 'self'",
"frame-ancestors 'none'",
].join("; ");
}
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