headplane/app/routes/acls/acl-loader.ts
2025-04-03 12:57:06 -04:00

65 lines
2.3 KiB
TypeScript

import { LoaderFunctionArgs } from 'react-router';
import { LoadContext } from '~/server';
import ResponseError from '~/server/headscale/api-error';
import { Capabilities } from '~/server/web/roles';
import { data403 } from '~/utils/res';
// The logic for deciding policy factors is very complicated because
// there are so many factors that need to be accounted for:
// 1. Does the user have permission to read the policy?
// 2. Does the user have permission to write to the policy?
// 3. Is the Headscale policy in file or database mode?
// If database, we can read/write easily via the API.
// If in file mode, we can only write if context.config is available.
// TODO: Consider adding back file editing mode instead of database
export async function aclLoader({
request,
context,
}: LoaderFunctionArgs<LoadContext>) {
const session = await context.sessions.auth(request);
const check = await context.sessions.check(request, Capabilities.read_policy);
if (!check) {
throw data403('You do not have permission to read the ACL policy.');
}
const flags = {
// Can the user write to the ACL policy
access: await context.sessions.check(request, Capabilities.write_policy),
writable: false,
policy: '',
};
// Try to load the ACL policy from the API.
try {
const { policy, updatedAt } = await context.client.get<{
policy: string;
updatedAt: string | null;
}>('v1/policy', session.get('api_key')!);
// Successfully loaded the policy, mark it as readable
// If `updatedAt` is null, it means the policy is in file mode.
flags.writable = updatedAt !== null;
flags.policy = policy;
return flags;
} catch (error) {
// This means Headscale returned a protobuf error to us
// It also means we 100% know this is in database mode
if (error instanceof ResponseError && error.responseObject?.message) {
const message = error.responseObject.message as string;
// This is stupid, refer to the link
// https://github.com/juanfont/headscale/blob/main/hscontrol/types/policy.go
if (message.includes('acl policy not found')) {
// This means the policy has never been initiated, and we can
// write to it to get it started or ignore it.
flags.policy = ''; // Start with an empty policy
flags.writable = true;
}
return flags;
}
// Otherwise, this is a Headscale error that we can just propagate.
throw error;
}
}