DC-151: WG nftables matrix compiler + transactional apply/rollback + tests

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/**
* Tests for src/network/wg-firewall.js (DC-151).
* Coverage:
* - golden ruleset text: single resource single grant, group grant
* expansion, blocked person absent from ALL sets, default-deny tails,
* admin ports only from admin set
* - corrected baseline: WG UDP handshake rule NOT bound to dcnet0
* (externalInterface scoping + null → unscoped), peer-to-peer forward
* default-deny (oifname dcnet0 drop)
* - name sanitization: 'plex-2!' → net_dc_res_plex_2, collision guard
* - admin lockout guard; assertAdminIsolation (positive + adversarial)
* - transactional apply (mocked execFile + fs): check-failure → no apply
* + temp deleted; apply-failure → {applied:false} + rollback file
* unchanged; verify-mismatch → rollback attempted; rollback() re-applies
* previous; unique temp paths across applies
*/
'use strict';
const {
compileRuleset,
createWgFirewallApplier,
assertAdminIsolation,
resourceSetName,
FirewallCheckError,
FirewallApplyError,
} = require('../src/network/wg-firewall');
// --------------------------------------------------------------------------
// Fixtures
// --------------------------------------------------------------------------
const PEOPLE = [
{
id: 'admin1',
displayName: 'Admin',
groups: ['family'],
status: 'active',
devices: [{ keyId: 'k1', name: 'laptop', ip: '10.53.0.10' }],
},
{
id: 'alice',
displayName: 'Alice',
groups: ['family'],
status: 'active',
devices: [{ keyId: 'k2', name: 'phone', ip: '10.53.1.20' }],
},
{
id: 'bob',
displayName: 'Bob',
groups: [],
status: 'active',
devices: [{ keyId: 'k3', name: 'pc', ip: '10.53.2.30' }],
},
{
id: 'mallory',
displayName: 'Mallory',
groups: ['family'],
status: 'blocked',
devices: [{ keyId: 'k4', name: 'tab', ip: '10.53.3.40' }],
},
];
const PEERS = {
'admin1/dev1': '10.53.0.10',
'alice/dev1': '10.53.1.20',
'bob/dev1': '10.53.2.30',
'mallory/dev1': '10.53.3.40',
};
const RESOURCES = {
plex: { ip: '10.53.0.1', port: 32400, protocol: 'tcp' },
nas: { ip: '10.53.9.9', port: 445, protocol: 'tcp' },
};
const BASE = {
accessMap: { grants: [] },
people: PEOPLE,
peerAddresses: PEERS,
resources: RESOURCES,
adminPeers: ['admin1'],
};
// --------------------------------------------------------------------------
// Compiler: golden ruleset text
// --------------------------------------------------------------------------
describe('wg-firewall: compileRuleset golden text', () => {
test('single resource single grant — exact set element + accept rule', () => {
const text = compileRuleset({
...BASE,
accessMap: {
grants: [{ principal: { type: 'person', id: 'alice' }, resource: 'plex', allowed: true }],
},
resources: { plex: RESOURCES.plex },
});
expect(text).toContain('set net_dc_res_plex {');
expect(text).toContain('elements = { 10.53.1.20 }');
expect(text).toContain(
'ip saddr @net_dc_res_plex ip daddr 10.53.0.1 tcp dport 32400 accept comment "resource plex"'
);
// blocked + ungranted peers are NOT in the plex resource set
const plexSet = text.split('set net_dc_res_plex {')[1].split('}')[0];
expect(plexSet).not.toContain('10.53.3.40'); // mallory
expect(plexSet).not.toContain('10.53.2.30'); // bob
expect(plexSet).not.toContain('10.53.0.10'); // admin not granted plex → not in res set
expect(plexSet).toContain('elements = { 10.53.1.20');
});
test('group grant expands to every active member (person-override honored)', () => {
const text = compileRuleset({
...BASE,
accessMap: {
grants: [
{ principal: { type: 'group', id: 'family' }, resource: 'nas', allowed: true },
{ principal: { type: 'person', id: 'alice' }, resource: 'nas', allowed: false },
],
},
resources: { nas: RESOURCES.nas },
});
// family = admin1, alice, mallory(blocked); alice overridden to false
expect(text).toMatch(/set net_dc_res_nas \{\s*\n\s*type ipv4_addr\s*\n\s*elements = \{ 10\.53\.0\.10 \}/);
expect(text).toContain('ip saddr @net_dc_res_nas ip daddr 10.53.9.9 tcp dport 445 accept');
});
test('blocked person absent from ALL sets (resource sets and admin set)', () => {
const text = compileRuleset({
...BASE,
accessMap: {
grants: [{ principal: { type: 'group', id: 'family' }, resource: 'plex', allowed: true }],
},
adminPeers: ['admin1', 'mallory'], // mallory blocked → must NOT get admin
});
const adminSetMatch = text.match(/set net_dc_admins \{[^}]*elements = \{ ([^}]*) \}/);
expect(adminSetMatch).toBeTruthy();
const adminEls = adminSetMatch[1].split(', ');
expect(adminEls).toEqual(['10.53.0.10']); // mallory's 10.53.3.40 excluded
expect(adminEls).not.toContain('10.53.3.40');
});
test('default-deny tails present: hub input, peer egress, peer-to-peer', () => {
const text = compileRuleset(BASE);
expect(text).toContain('ct state new drop comment "default-deny: hub input"');
expect(text).toContain('drop comment "default-deny: peer egress without grant"');
expect(text).toContain('drop comment "default-deny: peer-to-peer / new hub-to-peer"');
});
test('admin ports only from admin set (3001 + 22)', () => {
const text = compileRuleset(BASE);
expect(text).toContain(
'iifname "dcnet0" ip saddr @net_dc_admins tcp dport { 22, 3001 } accept comment "admin ports: admin peers only"'
);
});
test('table declared as inet dcnet with destroy-first', () => {
const text = compileRuleset(BASE);
expect(text).toContain('destroy table inet dcnet');
expect(text).toContain('table inet dcnet {');
});
});
// --------------------------------------------------------------------------
// Compiler: corrected baseline (judge gate)
// --------------------------------------------------------------------------
describe('wg-firewall: WG UDP handshake + peer-to-peer baseline (corrected)', () => {
test('UDP allow rule is NOT bound to dcnet0 — scoped to external interface', () => {
const text = compileRuleset({ ...BASE, externalInterface: 'eth0' });
const udpLines = text.split('\n').filter((l) => l.includes('udp dport 51820'));
expect(udpLines).toHaveLength(1);
expect(udpLines[0]).toContain('iifname "eth0"');
expect(udpLines[0]).not.toContain('dcnet0');
});
test('externalInterface null → unscoped UDP rule with comment', () => {
const text = compileRuleset(BASE);
const udpLines = text.split('\n').filter((l) => l.includes('udp dport 51820'));
expect(udpLines).toHaveLength(1);
expect(udpLines[0]).not.toContain('iifname');
expect(udpLines[0]).toContain('external iface unspecified');
});
test('custom listen port honored', () => {
const text = compileRuleset({ ...BASE, wgListenPort: 51821, externalInterface: 'ens3' });
expect(text).toContain('iifname "ens3" udp dport 51821 accept');
});
test('peer-to-peer forwarding default-deny: oifname dcnet0 drop tail', () => {
const text = compileRuleset(BASE);
expect(text).toContain('oifname "dcnet0" drop');
// and no accept rule that would let peer→peer through ahead of it
const forward = text.split('chain forward {')[1].split('}')[0];
expect(forward).not.toMatch(/oifname "dcnet0".*accept/);
});
test('hub-local resource lands in input chain; peer resource in forward chain', () => {
const text = compileRuleset({
...BASE,
accessMap: {
grants: [{ principal: { type: 'person', id: 'alice' }, resource: 'nas', allowed: true }],
},
});
const input = text.split('chain input {')[1].split('chain forward')[0];
const forward = text.split('chain forward {')[1];
expect(input).toContain('@net_dc_res_plex');
expect(input).not.toContain('@net_dc_res_nas');
expect(forward).toContain('@net_dc_res_nas');
expect(forward).not.toContain('@net_dc_res_plex');
});
});
// --------------------------------------------------------------------------
// Compiler: sanitization + guards
// --------------------------------------------------------------------------
describe('wg-firewall: sanitization and guards', () => {
test("resource 'plex-2!' sanitizes to a safe set name", () => {
expect(resourceSetName('plex-2!')).toBe('net_dc_res_plex_2');
const text = compileRuleset({
...BASE,
resources: { 'plex-2!': { ip: '10.53.0.1', port: 32400 } },
accessMap: {
grants: [{ principal: { type: 'person', id: 'alice' }, resource: 'plex-2!', allowed: true }],
},
});
expect(text).toContain('set net_dc_res_plex_2 {');
expect(text).toContain('@net_dc_res_plex_2');
expect(text).toContain('ip saddr @net_dc_res_plex_2 ip daddr 10.53.0.1 tcp dport 32400 accept');
});
test('set-name collision between distinct resources throws', () => {
expect(() =>
compileRuleset({ ...BASE, resources: { 'plex 1': { ip: '10.53.0.1', port: 1 }, 'plex!1': { ip: '10.53.0.2', port: 2 } } })
).toThrow(/collision/);
});
test('admin lockout guard: zero resolvable admin peers throws', () => {
expect(() => compileRuleset({ ...BASE, adminPeers: ['ghost'] })).toThrow(/lockout/);
});
test('invalid resource (missing ip / bad port) throws', () => {
expect(() => compileRuleset({ ...BASE, resources: { x: { port: 80 } } })).toThrow(/ip required/);
expect(() => compileRuleset({ ...BASE, resources: { x: { ip: '10.53.0.1', port: 0 } } })).toThrow(/port/);
});
});
// --------------------------------------------------------------------------
// assertAdminIsolation
// --------------------------------------------------------------------------
describe('wg-firewall: assertAdminIsolation', () => {
test('passes on a correctly compiled ruleset', () => {
const text = compileRuleset(BASE);
expect(assertAdminIsolation(text, { adminPeers: ['admin1'] })).toBe(true);
});
test('rejects an admin port allowed without the admin set', () => {
const bad = 'iifname "dcnet0" tcp dport 22 accept';
expect(() => assertAdminIsolation(bad)).toThrow(/without @net_dc_admins/);
});
test('rejects an admin port allowed from a resource set', () => {
const bad = 'iifname "dcnet0" ip saddr @net_dc_res_plex tcp dport 3001 accept';
expect(() => assertAdminIsolation(bad)).toThrow(/resource set/);
});
test('rejects an admin port allowed from a literal peer IP', () => {
const bad = 'iifname "dcnet0" ip saddr 10.53.4.4 tcp dport 22 accept';
expect(() => assertAdminIsolation(bad)).toThrow(/literal peer saddr/);
});
});
// --------------------------------------------------------------------------
// Transactional applier (hermetic: mocked execFile + fs)
// --------------------------------------------------------------------------
function mockFs() {
const files = new Map();
return {
files,
writeFileSync: jest.fn((p, c) => files.set(p, c)),
readFileSync: jest.fn((p) => {
if (!files.has(p)) { const e = new Error('ENOENT'); e.code = 'ENOENT'; throw e; }
return files.get(p);
}),
existsSync: jest.fn((p) => files.has(p)),
unlinkSync: jest.fn((p) => files.delete(p)),
};
}
/** execFile mock with a per-call script of behaviors keyed by args. */
function mockExec({ current = 'table inet dcnet { }', checkErr, applyErr, verifyOut } = {}) {
const calls = [];
const impl = async (cmd, args) => { // eslint-disable-line require-await -- scripted mock, no awaits by design
calls.push({ cmd, args: [...args] });
const joined = args.join(' ');
if (joined.startsWith('-c -f')) {
if (checkErr) {
const e = new Error('check failed');
e.stderr = 'syntax error near unexpected token';
throw e;
}
return { stdout: '' };
}
if (joined.startsWith('-f')) {
if (applyErr) {
const e = new Error('apply failed');
e.stderr = 'operation failed: Device or resource busy';
throw e;
}
return { stdout: '' };
}
if (joined.startsWith('list table')) {
if (verifyOut !== undefined) return { stdout: verifyOut };
return { stdout: current };
}
return { stdout: '' };
};
return { impl, calls };
}
const RULESET = compileRuleset(BASE);
const RULESET2 = compileRuleset({
...BASE,
accessMap: { grants: [{ principal: { type: 'person', id: 'bob' }, resource: 'plex', allowed: true }] },
});
describe('wg-firewall: transactional apply', () => {
test('happy path: check → rollback write → apply → verify; temp cleaned up', async () => {
const fs = mockFs();
const { impl, calls } = mockExec();
const applier = createWgFirewallApplier({
execFileImpl: impl,
fsImpl: fs,
tempDir: '/tmp/x',
rollbackPath: '/tmp/x/rollback.nft',
});
const res = await applier.apply(RULESET);
expect(res.applied).toBe(true);
expect(res.verified).toBe(true);
// order: check(-c -f) before rollback write before apply(-f) before verify
const checkIdx = calls.findIndex((c) => c.args[0] === '-c');
const applyIdx = calls.findIndex((c) => c.args[0] === '-f');
const listIdxs = calls.map((c, i) => (c.args[0] === 'list' ? i : -1)).filter((i) => i >= 0);
expect(checkIdx).toBe(0);
expect(applyIdx).toBeGreaterThan(checkIdx);
// one `list` before apply (capture previous) + one after (verify)
expect(listIdxs).toHaveLength(2);
expect(listIdxs[0]).toBeLessThan(applyIdx);
expect(listIdxs[1]).toBeGreaterThan(applyIdx);
const writePaths = fs.writeFileSync.mock.calls.map((c) => c[0]);
const tempWrites = writePaths.filter((p) => p !== '/tmp/x/rollback.nft');
expect(tempWrites).toHaveLength(1);
const tempPath = tempWrites[0];
// write order: temp (for check) then rollback BEFORE the apply exec
expect(writePaths).toEqual([tempPath, '/tmp/x/rollback.nft']);
const applyCall = calls[applyIdx];
expect(applyCall.args).toEqual(['-f', tempPath]);
expect(applyCall.args[1]).not.toBe('/tmp/x/rollback.nft');
// rollback file holds the PREVIOUS table dump
expect(fs.readFileSync('/tmp/x/rollback.nft')).toBe('table inet dcnet { }');
// temp file deleted at the end
expect(fs.existsSync(tempPath)).toBe(false);
expect(res.previousExisted).toBe(true);
});
test('check failure → no apply, temp deleted, FirewallCheckError with stderr', async () => {
const fs = mockFs();
const { impl, calls } = mockExec({ checkErr: true });
const applier = createWgFirewallApplier({
execFileImpl: impl, fsImpl: fs, tempDir: '/tmp/x', rollbackPath: '/tmp/x/rollback.nft',
});
await expect(applier.apply(RULESET)).rejects.toMatchObject({
name: 'FirewallCheckError',
code: 'check_failed',
applied: false,
stderr: expect.stringContaining('syntax error'),
});
// NOTHING applied: no bare `-f` run, no `nft list` verify, no rollback write
expect(calls.filter((c) => c.args[0] === '-f')).toHaveLength(0);
expect(calls.filter((c) => c.args[0] === 'list')).toHaveLength(0);
expect(fs.writeFileSync).toHaveBeenCalledTimes(1); // only the temp file
expect(fs.files.size).toBe(0); // temp deleted
});
test('apply failure → {applied:false} thrown, rollback file unchanged, old rules intact', async () => {
const fs = mockFs();
fs.files.set('/tmp/x/rollback.nft', 'PREVIOUS-ROLLBACK-CONTENT');
const { impl, calls } = mockExec({ applyErr: true });
const applier = createWgFirewallApplier({
execFileImpl: impl, fsImpl: fs, tempDir: '/tmp/x', rollbackPath: '/tmp/x/rollback.nft',
});
await expect(applier.apply(RULESET)).rejects.toMatchObject({
name: 'FirewallApplyError',
applied: false,
});
// rollback file NOT overwritten by the failed apply (old rules intact)
expect(fs.readFileSync('/tmp/x/rollback.nft')).toBe('PREVIOUS-ROLLBACK-CONTENT');
// temp cleaned, only the rollback file remains
expect(fs.files.size).toBe(1);
// verify never reached: the only `nft -f` run is the failed apply —
// no rollback re-apply, and exactly one `list` (the pre-apply capture)
expect(calls.filter((c) => c.args[0] === '-f')).toHaveLength(1);
expect(calls.filter((c) => c.args[0] === 'list')).toHaveLength(1);
});
test('verify mismatch → rollback attempted, verify error carries rolledBack', async () => {
const fs = mockFs();
const { impl, calls } = mockExec({ verifyOut: '' }); // list returns no table
const applier = createWgFirewallApplier({
execFileImpl: impl, fsImpl: fs, tempDir: '/tmp/x', rollbackPath: '/tmp/x/rollback.nft',
});
await expect(applier.apply(RULESET)).rejects.toMatchObject({
name: 'FirewallVerifyError',
code: 'verify_failed',
rolledBack: true,
});
// last exec is the rollback `nft -f <rollbackFile>`
const last = calls[calls.length - 1];
expect(last.args).toEqual(['-f', '/tmp/x/rollback.nft']);
});
test('rollback() re-applies the previous ruleset file', async () => {
const fs = mockFs();
fs.files.set('/tmp/x/rollback.nft', 'table inet dcnet { OLD }');
const { impl, calls } = mockExec();
const applier = createWgFirewallApplier({
execFileImpl: impl, fsImpl: fs, tempDir: '/tmp/x', rollbackPath: '/tmp/x/rollback.nft',
});
const res = await applier.rollback();
expect(res.applied).toBe(true);
expect(calls).toHaveLength(1);
expect(calls[0].args).toEqual(['-f', '/tmp/x/rollback.nft']);
});
test('rollback() without a rollback file throws', async () => {
const fs = mockFs();
const { impl } = mockExec();
const applier = createWgFirewallApplier({
execFileImpl: impl, fsImpl: fs, tempDir: '/tmp/x', rollbackPath: '/tmp/x/rollback.nft',
});
await expect(applier.rollback()).rejects.toThrow(/no rollback file/);
});
test('two applies never share a temp path', async () => {
const fs = mockFs();
const { impl } = mockExec();
const applier = createWgFirewallApplier({
execFileImpl: impl, fsImpl: fs, tempDir: '/tmp/x', rollbackPath: '/tmp/x/rollback.nft',
});
const r1 = await applier.apply(RULESET);
const r2 = await applier.apply(RULESET2);
expect(r1.tempPath).not.toBe(r2.tempPath);
expect(r1.tempPath).toMatch(/dcnet-nft-/);
expect(r2.tempPath).toMatch(/dcnet-nft-/);
});
test('apply rejects empty/non-string ruleset before any I/O', async () => {
const fs = mockFs();
const { impl, calls } = mockExec();
const applier = createWgFirewallApplier({ execFileImpl: impl, fsImpl: fs });
await expect(applier.apply('')).rejects.toThrow(/non-empty/);
expect(calls).toHaveLength(0);
expect(fs.writeFileSync).not.toHaveBeenCalled();
});
test('FirewallCheckError is exported and distinguishable', () => {
const e = new FirewallCheckError('x', { stderr: 's' });
expect(e instanceof Error).toBe(true);
expect(e.applied).toBe(false);
expect(new FirewallApplyError('y').applied).toBe(false);
});
});
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/**
* WireGuard hub firewall for the DashCaddy Private Network (DC-151,
* specs/PRIVATE-NETWORK-SPEC.md §4 "Layer 1 — WireGuard" + §8.1 baseline).
*
* Two halves:
*
* 1. compileRuleset() — a PURE compiler (no I/O, fully deterministic):
* access map + people + peer addresses + resources → the complete
* nftables ruleset text for table `inet dcnet`.
*
* Baseline model (corrected per judge-gate review of §8.1):
* - The WireGuard UDP listen port carries HANDSHAKE traffic that
* arrives on the EXTERNAL interface, never on dcnet0. The accept
* rule is scoped to `externalInterface` when given, otherwise
* emitted interface-unscoped with an explanatory comment.
* - dcnet0 LOCAL input (input chain, iifname "dcnet0"): established/
* related, ICMP from 10.53.0.0/16, admin ports (API 3001 / SSH 22)
* ONLY from the admin set, hub-local resource ports to 10.53.0.1,
* then drop other new inbound to the hub IP.
* - PEER traffic (forward chain): per-resource nft sets
* (`net_dc_res_<name>`) gate saddr→resource ip:dport for resources
* living at peer /32s; default-deny tails drop ALL other iifname
* "dcnet0" (peer egress without a grant) and oifname "dcnet0"
* (peer-to-peer + new hub→peer) traffic.
*
* Default-deny everywhere on dcnet0-derived traffic; blocked people's
* IPs appear in NO set (resource sets nor the admin set).
*
* 2. createWgFirewallApplier() — transactional apply with injectable
* { execFileImpl, fsImpl }: write to a UNIQUE temp file, `nft -c -f`
* (check), write the rollback file (previous ruleset) BEFORE applying,
* `nft -f` (apply), verify via `nft list table inet dcnet`, roll back
* on verify mismatch. A check failure deletes the temp file and throws
* FirewallCheckError with NOTHING applied; an apply failure leaves the
* old rules and the rollback file untouched and throws with
* { applied: false }.
*
* 3. assertAdminIsolation() — static guard (tests + DC-148-style callers):
* every admin-port rule must be scoped to the admin set only.
*/
'use strict';
const { execFile } = require('child_process');
const { promisify } = require('util');
const fsDefault = require('fs');
const os = require('os');
const path = require('path');
const execFileDefault = promisify(execFile);
const HUB_IP = '10.53.0.1';
const PEER_CIDR = '10.53.0.0/16';
const WG_IFACE = 'dcnet0';
const TABLE = 'inet dcnet';
const DEFAULT_ADMIN_PORTS = [22, 3001];
const DEFAULT_WG_LISTEN_PORT = 51820;
const ADMIN_SET = 'net_dc_admins';
const RES_SET_PREFIX = 'net_dc_res_';
// ---------------------------------------------------------------------------
// Errors
// ---------------------------------------------------------------------------
class FirewallError extends Error {
/**
* @param {string} message
* @param {object} [opts]
* @param {string} [opts.code] - machine-readable code
* @param {boolean} [opts.applied] - did any part of the new ruleset land?
* @param {string} [opts.stderr] - captured nft stderr, when available
* @param {*} [opts.cause]
*/
constructor(message, { code, applied, stderr, cause, rolledBack } = {}) {
super(message);
this.name = this.constructor.name;
this.code = code || 'firewall_error';
this.applied = !!applied;
if (stderr !== undefined) this.stderr = stderr;
if (cause !== undefined) this.cause = cause;
if (rolledBack !== undefined) this.rolledBack = !!rolledBack;
}
}
/** `nft -c -f` rejected the ruleset. Nothing was applied; temp deleted. */
class FirewallCheckError extends FirewallError {
constructor(message, opts = {}) {
super(message, { ...opts, code: 'check_failed', applied: false });
}
}
/** `nft -f` failed. Old rules and rollback file are untouched. */
class FirewallApplyError extends FirewallError {
constructor(message, opts = {}) {
super(message, { ...opts, code: 'apply_failed', applied: false });
}
}
/** Post-apply verification failed. Rollback was attempted. */
class FirewallVerifyError extends FirewallError {
constructor(message, opts = {}) {
super(message, { ...opts, code: 'verify_failed', applied: true });
}
}
// ---------------------------------------------------------------------------
// Pure compiler
// ---------------------------------------------------------------------------
/**
* Sanitize a resource name into a safe nftables identifier segment.
* 'plex-2!' → 'plex_2'; leading digits get a 'res_' prefix; empty → 'unnamed'.
* @param {string} name
* @returns {string}
*/
function sanitizeResourceSegment(name) {
const raw = String(name)
.toLowerCase()
.replace(/[^a-z0-9_]+/g, '_')
.replace(/^_+|_+$/g, '');
if (!raw) return 'unnamed';
return /^[0-9]/.test(raw) ? 'res_' + raw : raw;
}
/** Full set name for a resource: net_dc_res_<sanitized>. */
function resourceSetName(resourceName) {
return RES_SET_PREFIX + sanitizeResourceSegment(resourceName);
}
function _personStatus(person) {
return person && typeof person.status === 'string' ? person.status : 'active';
}
/**
* Effective access for one person, mirroring the access store semantics
* (src/security/network-access-store.js effectiveAccess): union of the
* grants of every group they belong to, then person-level grants OVERRIDE
* group grants in both directions.
* @returns {Object<string, boolean>} resource → allowed
*/
function computePersonAccess(accessMap, person) {
const grants = accessMap && Array.isArray(accessMap.grants) ? accessMap.grants : [];
const groups = new Set(
Array.isArray(person.groups) ? person.groups.filter((g) => typeof g === 'string') : []
);
const resources = {};
for (const g of grants) {
if (g && g.principal && g.principal.type === 'group' && groups.has(g.principal.id)) {
resources[g.resource] = g.allowed;
}
}
for (const g of grants) {
if (g && g.principal && g.principal.type === 'person' && g.principal.id === person.id) {
resources[g.resource] = g.allowed;
}
}
return resources;
}
/**
* All assigned peer IPs for a person. `peerAddresses` is the flat map
* `${personId}/${deviceId}` → 10.53.x.y (canonical), with a nested
* { [personId]: { [deviceId]: ip } } shape also accepted.
* @returns {string[]} sorted unique IPs
*/
function peerIpsForPerson(peerAddresses, person) {
const ips = [];
const prefix = person.id + '/';
for (const [key, ip] of Object.entries(peerAddresses || {})) {
if (typeof ip === 'string' && key.startsWith(prefix) && key.length > prefix.length) {
ips.push(ip);
}
}
const nested = peerAddresses ? peerAddresses[person.id] : null;
if (nested && typeof nested === 'object') {
for (const ip of Object.values(nested)) {
if (typeof ip === 'string') ips.push(ip);
}
}
return [...new Set(ips)].sort();
}
function _dportList(ports) {
const sorted = [...ports].map((p) => parseInt(p, 10)).sort((a, b) => a - b);
return `{ ${sorted.join(', ')} }`;
}
/**
* Resolve the admin set IPs from ACTIVE admin people. Blocked/removed admins
* contribute nothing. Throws (lockout guard) when admin ports would be
* emitted with zero reachable admin peers.
* @returns {string[]} sorted unique admin peer IPs
*/
function _resolveAdminIps(activePersons, adminPeers, peerAddresses) {
const adminIds = new Set(
Array.isArray(adminPeers) ? adminPeers.filter((id) => typeof id === 'string') : []
);
const ips = new Set();
for (const p of activePersons) {
if (!adminIds.has(p.id)) continue;
for (const ip of peerIpsForPerson(peerAddresses, p)) ips.add(ip);
}
if (ips.size === 0) {
throw new Error(
'wg-firewall: admin lockout guard — admin ports requested but no active admin peer IPs resolved'
);
}
return [...ips].sort();
}
/**
* Build the per-resource set entries and split resources into hub-local
* (input chain, ip === hub) vs peer (forward chain) buckets. Validates
* resource entries and guards against sanitization collisions.
* @returns {{resourceSets: Array, hubResources: Array, peerResources: Array}}
*/
function _buildResourceSets({ resources, activePersons, accessMap, peerAddresses }) {
const setNames = new Map(); // sanitized segment → resource name (collision guard)
const resourceSets = [];
const hubResources = [];
const peerResources = [];
for (const [name, resource] of Object.entries(resources)) {
if (!resource || typeof resource.ip !== 'string' || !resource.ip) {
throw new Error(`wg-firewall: resource ${name}: ip required`);
}
if (!Number.isInteger(resource.port) || resource.port < 1 || resource.port > 65535) {
throw new Error(`wg-firewall: resource ${name}: valid port required`);
}
const segment = sanitizeResourceSegment(name);
const collides = setNames.get(segment);
if (collides && collides !== name) {
throw new Error(
`wg-firewall: set-name collision — resources "${collides}" and "${name}" both sanitize to ${RES_SET_PREFIX}${segment}`
);
}
setNames.set(segment, name);
const ips = new Set();
for (const person of activePersons) {
if (computePersonAccess(accessMap, person)[name] === true) {
for (const ip of peerIpsForPerson(peerAddresses, person)) ips.add(ip);
}
}
const setName = RES_SET_PREFIX + segment;
resourceSets.push({ name, setName, ips: [...ips].sort() });
const bucket = resource.ip === HUB_IP ? hubResources : peerResources;
bucket.push({ name, setName, resource });
}
return { resourceSets, hubResources, peerResources };
}
function _resourceRule(setName, resource, comment) {
const proto = resource.protocol === 'udp' ? 'udp' : 'tcp';
return `ip saddr @${setName} ip daddr ${resource.ip} ${proto} dport ${resource.port} accept comment "${comment}"`;
}
/**
* Compile the full nftables ruleset for the WireGuard hub.
*
* @param {object} opts
* @param {object} opts.accessMap - { grants: [...] } (network-access.json)
* @param {Array<object>} opts.people - person records {id, groups[], status,
* devices[]} from the people store
* @param {Object<string,string>} opts.peerAddresses - `${personId}/${deviceId}`
* → 10.53.x.y (nested {personId:{deviceId:ip}} also accepted)
* @param {Object<string,{ip:string,port:number,protocol?:'tcp'|'udp'}>} opts.resources
* @param {string[]} opts.adminPeers - person IDs allowed admin ports
* @param {number[]} [opts.adminPorts=[22,3001]]
* @param {number} [opts.wgListenPort=51820] - UDP handshake listen port
* @param {string|null} [opts.externalInterface=null] - external iface name for
* the WG handshake rule; null → unscoped rule with a comment
* @returns {string} complete nftables file text
* @throws {Error} on admin lockout (adminPorts with zero active admin peer
* IPs), set-name collisions, or invalid resource entries
*/
function compileRuleset({
accessMap = { grants: [] },
people = [],
peerAddresses = {},
resources = {},
adminPeers = [],
adminPorts = DEFAULT_ADMIN_PORTS,
wgListenPort = DEFAULT_WG_LISTEN_PORT,
externalInterface = null,
} = {}) {
if (!resources || typeof resources !== 'object' || Array.isArray(resources)) {
throw new Error('wg-firewall: resources map required');
}
const persons = Array.isArray(people) ? people : Object.values(people || {});
const active = persons.filter(
(p) => p && typeof p.id === 'string' && _personStatus(p) === 'active'
);
// ---- admin set (never includes blocked/removed people's IPs) ----------
const adminIps = _resolveAdminIps(active, adminPeers, peerAddresses);
const ports = adminPorts.length ? adminPorts : DEFAULT_ADMIN_PORTS;
// ---- per-resource sets + rule split (hub-local input vs peer forward) -
const { resourceSets, hubResources, peerResources } = _buildResourceSets({
resources,
activePersons: active,
accessMap,
peerAddresses,
});
// ---- emit -------------------------------------------------------------
const L = [];
L.push('#!/usr/sbin/nft -f');
L.push('# DashCaddy Private Network - WireGuard hub firewall (DC-151 wg-firewall)');
L.push('# GENERATED FILE - do not edit; recompiled from network-access.json.');
L.push('# Default-deny: blocked people appear in no set; unmatched dcnet0 traffic is dropped.');
L.push('');
L.push('destroy table inet dcnet');
L.push('');
L.push(`table ${TABLE} {`);
L.push('');
L.push(' # Admin peers allowed to reach hub admin ports');
L.push(` set ${ADMIN_SET} {`);
L.push(' type ipv4_addr');
L.push(` elements = { ${adminIps.join(', ')} }`);
L.push(' }');
L.push('');
for (const { name, setName, ips } of resourceSets) {
L.push(` # Resource grants: ${name}`);
L.push(` set ${setName} {`);
L.push(' type ipv4_addr');
if (ips.length) {
L.push(` elements = { ${ips.join(', ')} }`);
}
L.push(' }');
L.push('');
}
L.push(' chain input {');
L.push(' type filter hook input priority 0; policy accept;');
L.push('');
L.push(' # WireGuard handshake: arrives on the EXTERNAL interface, never dcnet0');
if (externalInterface) {
L.push(
` iifname "${externalInterface}" udp dport ${wgListenPort} accept comment "wg handshake on external iface"`
);
} else {
L.push(
` udp dport ${wgListenPort} accept comment "wg handshake - external iface unspecified, left unscoped"`
);
}
L.push('');
L.push(' # dcnet0 local input');
L.push(` iifname "${WG_IFACE}" ct state established,related accept comment "dcnet0 established/related"`);
L.push(
` iifname "${WG_IFACE}" ip saddr ${PEER_CIDR} icmp type echo-request accept comment "icmp from peers"`
);
L.push(
` iifname "${WG_IFACE}" ip saddr @${ADMIN_SET} tcp dport ${_dportList(ports)} accept comment "admin ports: admin peers only"`
);
for (const { name, setName, resource } of hubResources) {
L.push(
` iifname "${WG_IFACE}" ${_resourceRule(setName, resource, `resource ${name}`)}`
);
}
L.push(
` iifname "${WG_IFACE}" ip daddr ${HUB_IP} ct state new drop comment "default-deny: hub input"`
);
L.push(' }');
L.push('');
L.push(' chain forward {');
L.push(' type filter hook forward priority 0; policy accept;');
L.push('');
L.push(` iifname "${WG_IFACE}" ct state established,related accept comment "dcnet0 established/related"`);
for (const { name, setName, resource } of peerResources) {
L.push(` iifname "${WG_IFACE}" ${_resourceRule(setName, resource, `resource ${name}`)}`);
}
L.push(` iifname "${WG_IFACE}" drop comment "default-deny: peer egress without grant"`);
L.push(` oifname "${WG_IFACE}" drop comment "default-deny: peer-to-peer / new hub-to-peer"`);
L.push(' }');
L.push('}');
L.push('');
return L.join('\n');
}
// ---------------------------------------------------------------------------
// Static admin-isolation guard
// ---------------------------------------------------------------------------
/**
* Assert that every admin-port rule in the ruleset references ONLY the
* admin set: an admin port may not be allowed from a resource set, a
* literal peer IP, or with no source scoping at all.
*
* @param {string} rulesetText - compiled nftables file text
* @param {object} [opts]
* @param {number[]} [opts.adminPorts=[22,3001]]
* @returns {true} when isolated
* @throws {Error} (name 'AdminIsolationError', .violations[]) otherwise
*/
function assertAdminIsolation(rulesetText, { adminPorts = DEFAULT_ADMIN_PORTS } = {}) {
const ports = new Set(adminPorts.map((p) => String(parseInt(p, 10))));
const violations = [];
for (const line of String(rulesetText).split('\n')) {
const m = line.match(/dport\s+(?:\{\s*([^}]*?)\s*\}|(\d+))/);
if (!m) continue;
const listed = (m[1] ? m[1].split(/[,\s]+/) : [m[2]]).filter(Boolean);
if (!listed.some((p) => ports.has(p))) continue;
const trimmed = line.trim();
if (!line.includes(`@${ADMIN_SET}`)) {
violations.push(`admin port allowed without @${ADMIN_SET}: ${trimmed}`);
}
if (line.includes(`@${RES_SET_PREFIX}`)) {
violations.push(`admin port rule references a resource set: ${trimmed}`);
}
if (/ip saddr 10\.53\.\d/.test(line)) {
violations.push(`admin port rule uses a literal peer saddr: ${trimmed}`);
}
}
if (violations.length) {
const err = new Error('admin isolation violation:\n ' + violations.join('\n '));
err.name = 'AdminIsolationError';
err.violations = violations;
throw err;
}
return true;
}
// ---------------------------------------------------------------------------
// Transactional applier
// ---------------------------------------------------------------------------
let _tempSeq = 0;
/** mkstemp-style unique temp path — never a fixed path. */
function _uniqueTempPath(dir) {
_tempSeq += 1;
const rand = Math.random().toString(36).slice(2, 10);
return path.join(dir, `dcnet-nft-${process.pid}-${_tempSeq}-${rand}.nft`);
}
function _errStderr(err) {
if (!err) return '';
if (typeof err.stderr === 'string') return err.stderr;
return err.message || String(err);
}
function _bestEffortUnlink(fs, p) {
try {
fs.unlinkSync(p);
} catch {
/* already gone — fine */
}
}
/**
* Build the transactional nftables applier.
*
* @param {object} [deps] - all injectable (hermetic tests mock these)
* @param {Function} [deps.execFileImpl] - promisified execFile(cmd, args)
* @param {object} [deps.fsImpl] - { writeFileSync, readFileSync, existsSync,
* unlinkSync }
* @param {string} [deps.nftBinary='nft']
* @param {string} [deps.tempDir] - directory for unique temp ruleset files
* @param {string} [deps.rollbackPath] - where the previous ruleset is kept
*/
function createWgFirewallApplier({
execFileImpl,
fsImpl,
nftBinary = 'nft',
tempDir,
rollbackPath,
} = {}) {
const execFn = execFileImpl || execFileDefault;
const fs = fsImpl || fsDefault;
const tmpDir = tempDir || path.join(os.tmpdir());
const rollbackFile =
rollbackPath || path.join(tmpDir, 'dashcaddy-dcnet-rollback.nft');
async function nft(args) { // eslint-disable-line require-await -- passthrough to injected execFile promise
return execFn(nftBinary, args);
}
/**
* Capture the currently-applied dcnet table, or null when absent.
* @returns {Promise<string|null>}
*/
async function captureCurrent() {
try {
const res = await nft(['list', 'table', 'inet', 'dcnet']);
return res && typeof res.stdout === 'string' ? res.stdout : null;
} catch {
return null; // table does not exist yet — first apply
}
}
return {
rollbackFile,
/**
* Transactional apply:
* 1. write ruleset to a UNIQUE temp file
* 2. `nft -c -f` — on failure delete temp, throw FirewallCheckError,
* nothing applied
* 3. write the rollback file (previous ruleset) BEFORE applying
* 4. `nft -f` — on failure delete temp, throw FirewallApplyError
* {applied:false}; old rules + rollback file untouched
* 5. verify via `nft list table inet dcnet`; mismatch → attempt
* rollback, throw FirewallVerifyError {applied:true, rolledBack}
*
* @param {string} rulesetText
* @returns {Promise<{applied:true, verified:true, tempPath:string,
* rollbackFile:string, previousExisted:boolean}>}
*/
async apply(rulesetText) {
if (typeof rulesetText !== 'string' || rulesetText.length === 0) {
throw new Error('wg-firewall: apply() requires non-empty ruleset text');
}
const tempPath = _uniqueTempPath(tmpDir);
fs.writeFileSync(tempPath, rulesetText);
// 1. check — reject before touching anything live.
try {
await nft(['-c', '-f', tempPath]);
} catch (err) {
_bestEffortUnlink(fs, tempPath);
throw new FirewallCheckError(
`nft -c rejected ruleset (${_errStderr(err).trim()})`,
{ stderr: _errStderr(err) }
);
}
// 2. snapshot previous + write rollback BEFORE applying. Keep the
// prior rollback file content so a FAILED apply leaves it (the
// last-known-good rollback) untouched.
const previous = await captureCurrent();
let priorRollback;
try {
priorRollback = fs.readFileSync(rollbackFile);
} catch {
priorRollback = undefined; // no prior rollback file
}
const rollbackContent = previous !== null ? previous : 'destroy table inet dcnet\n';
fs.writeFileSync(rollbackFile, rollbackContent);
// 3. apply.
try {
await nft(['-f', tempPath]);
} catch (err) {
_bestEffortUnlink(fs, tempPath);
if (priorRollback !== undefined) {
fs.writeFileSync(rollbackFile, priorRollback);
} else {
_bestEffortUnlink(fs, rollbackFile);
}
throw new FirewallApplyError(`nft -f apply failed (${_errStderr(err).trim()})`, {
stderr: _errStderr(err),
});
}
// 4. verify.
let verified = false;
let verifyStderr = '';
try {
const res = await nft(['list', 'table', 'inet', 'dcnet']);
const out = res && typeof res.stdout === 'string' ? res.stdout : '';
verified = out.includes(TABLE);
if (!verified) verifyStderr = 'nft list table inet dcnet output missing table';
} catch (err) {
verifyStderr = _errStderr(err);
}
if (!verified) {
let rolledBack = false;
try {
await nft(['-f', rollbackFile]);
rolledBack = true;
} catch {
rolledBack = false;
}
_bestEffortUnlink(fs, tempPath);
throw new FirewallVerifyError(
`post-apply verify failed (${verifyStderr.trim()}); rollback ${
rolledBack ? 'succeeded' : 'FAILED — inspect host firewall manually'
}`,
{ stderr: verifyStderr, rolledBack }
);
}
_bestEffortUnlink(fs, tempPath);
return {
applied: true,
verified: true,
tempPath,
rollbackFile,
previousExisted: previous !== null,
};
},
/**
* Re-apply the rollback file (the pre-apply ruleset).
* @returns {Promise<{applied:true, rollbackFile:string}>}
* @throws {Error} when no rollback file exists or re-apply fails
*/
async rollback() {
if (!fs.existsSync(rollbackFile)) {
throw new Error(`wg-firewall: no rollback file at ${rollbackFile}`);
}
try {
await nft(['-f', rollbackFile]);
} catch (err) {
throw new FirewallApplyError(
`rollback re-apply failed (${_errStderr(err).trim()})`,
{ stderr: _errStderr(err) }
);
}
return { applied: true, rollbackFile };
},
};
}
module.exports = {
compileRuleset,
createWgFirewallApplier,
assertAdminIsolation,
sanitizeResourceSegment,
resourceSetName,
FirewallError,
FirewallCheckError,
FirewallApplyError,
FirewallVerifyError,
ADMIN_SET,
HUB_IP,
PEER_CIDR,
};