Files
msd-core/gsd-core/bin/lib/runtime-artifact-install-plan.cjs
Tom Boucher fb5f89db10 feat(#1704): destSubpath write-confinement (ADR-1239 Phase B) (#1706)
* feat(#1679): confine install writes within configHome

ADR-1239 Phase B write-confinement: a pure assertDestWithinConfigHome(configDir, destSubpath) rejects a destSubpath that escapes configHome (path traversal / NUL byte) at plan-build time on BOTH the install and uninstall plan paths; surface.applySurface and installOpencodeFamilySkills route through it, and _copyStaged carries a defense-in-depth containment check. Security-load-bearing for the Phase C third-party-descriptor loader.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(#1704): add changeset for destSubpath write-confinement

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* test(#1704): fix windows path-portability in confinement test

The N1 'accepts a true child subpath' assertion compared against path.join (no drive resolution) while the helper uses path.resolve — on Windows that mismatches the C: drive prefix. Compute the expected via path.resolve to mirror the helper. Windows-CI-only failure (local gsd-test is Mac+Linux).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-25 13:20:25 -04:00

102 lines
4.1 KiB
JavaScript

'use strict';
/**
* Runtime Artifact Install Plan Module.
*
* Turns a pre-resolved runtime artifact layout into staged copy inputs. The
* installer adapter still owns pruning, copying, migrations, output, and final
* cleanup execution.
*/
// In .cts (CommonJS output) files, `require` is available as a global.
const _require = require;
const path = _require('node:path');
/**
* Asserts that `destSubpath` resolves to a path inside `configDir`.
*
* Rejects any path that escapes the configDir root (e.g. "../../etc") and any
* path containing a NUL byte. This is a security gate for Phase B of
* ADR-1239: third-party descriptors must never be able to write outside the
* designated config home directory.
*
* @param configDir - The root config directory (e.g. ~/.claude).
* @param destSubpath - The relative path declared by the runtime descriptor.
* @returns The resolved absolute path under configDir.
* @throws {Error} if destSubpath escapes configDir or contains a NUL byte.
*/
function assertDestWithinConfigHome(configDir, destSubpath) {
if (destSubpath.includes('\0')) {
throw new Error(`destSubpath "${destSubpath}" contains a NUL byte and is not valid`);
}
const root = path.resolve(configDir);
const resolved = path.resolve(configDir, destSubpath);
if (resolved === root || !resolved.startsWith(root + path.sep)) {
throw new Error(`destSubpath "${destSubpath}" must be a strict subpath of configHome "${configDir}" — not configHome itself or outside it (escapes configHome)`);
}
return resolved;
}
function errorMessage(err) {
if (err instanceof Error)
return err.message;
return String(err);
}
function addCleanupDir(cleanupDirs, stagedDir, rewrittenDir) {
const sourceDir = rewrittenDir ?? stagedDir;
if (sourceDir !== stagedDir)
cleanupDirs.push(sourceDir);
return sourceDir;
}
function createRuntimeArtifactInstallPlan(args) {
const { layout, resolvedProfile, homedir, platform, resolveAttribution, deps = {}, } = args;
const conversionExports = _require('./runtime-artifact-conversion.cjs');
const rewriteStagedSkillBodies = deps.rewriteStagedSkillBodies ?? conversionExports.rewriteStagedSkillBodies;
const rewriteStagedCommandBodies = deps.rewriteStagedCommandBodies ?? conversionExports.rewriteStagedCommandBodies;
const cleanupDirs = [];
const items = [];
const scope = layout.scope ?? 'global';
const rewriteOpts = {
runtime: layout.runtime,
configDir: layout.configDir,
scope,
homedir,
platform,
resolveAttribution,
};
for (const kind of layout.kinds) {
let stagedDir;
try {
stagedDir = kind.stage(resolvedProfile);
}
catch (err) {
return { ok: false, kind: 'stage_failed', message: errorMessage(err), cleanupDirs, failedKind: kind.kind };
}
let sourceDir = stagedDir;
try {
if (kind.kind === 'commands') {
const rewrittenDir = rewriteStagedCommandBodies(stagedDir, rewriteOpts);
sourceDir = addCleanupDir(cleanupDirs, stagedDir, rewrittenDir);
}
else if (kind.kind === 'skills' || kind.kind === 'kimi-agents') {
const rewrittenDir = rewriteStagedSkillBodies(stagedDir, rewriteOpts);
sourceDir = addCleanupDir(cleanupDirs, stagedDir, rewrittenDir);
}
}
catch (err) {
return { ok: false, kind: 'rewrite_failed', message: errorMessage(err), cleanupDirs, failedKind: kind.kind };
}
items.push({
kind: kind.kind,
sourceDir,
destDir: assertDestWithinConfigHome(layout.configDir, kind.destSubpath),
});
}
return { ok: true, plan: { items, cleanupDirs } };
}
function createRuntimeArtifactUninstallPlan(layout) {
return {
items: layout.kinds.map((kind) => ({
kind: kind.kind,
destDir: assertDestWithinConfigHome(layout.configDir, kind.destSubpath),
})),
};
}
module.exports = { assertDestWithinConfigHome, createRuntimeArtifactInstallPlan, createRuntimeArtifactUninstallPlan };