Files
reverse-engineering-anything/tests/boundary/cli/dylibResolutionCli.test.ts
T
Kaoru0822andClaude Opus 5.5 11b7f918c2 feat(artifacts): trace Mach-O dylib resolution in bundles
Add trace_dylib_resolution (CLI trace-dylib-resolution) to the artifact
family. For the active Mach-O, or every executable in the active .app
(the main app, XPC services, extensions, login items, helpers), it
reports which file each dylib load reaches and how.

A pure TypeScript reader decodes FAT and Mach-O load commands:
LC_LOAD/WEAK/REEXPORT/LAZY/UPWARD_DYLIB, including the newer
dylib_use_command encoding with weak, re-export, upward and delayed-init
flags, plus LC_ID_DYLIB, LC_RPATH, LC_DYLD_ENVIRONMENT and code-signature
presence. Malformed tables are reported with the failing command instead
of being guessed.

Resolution follows dyld:
- @executable_path comes from each process root;
- @loader_path comes from the loading image, or from the owner of the
  LC_RPATH entry being expanded;
- @rpath searches the loader's rpaths first, then up the load chain;
- dependencies load dependents-first in load-command order, once per
  process, and a matching install name reuses an already loaded image;
- symlinks are followed inside the analyzed root, and escapes stop.

Every candidate path is reported with its outcome. Each edge resolves to
resolved, conditional (an outside-root candidate such as /usr/lib/swift
precedes), unresolved, or undetermined. Absolute and shared-cache system
paths are never checked against the host. Derived findings cover
unresolved required or weak loads, absent earlier @rpath candidates (with
library validation left unknown), and LC_DYLD_ENVIRONMENT.

verify:macos-bundle now also:
- checks every traced image against otool -l;
- asserts each resolution status on a clang-built fixture that adds a
  missing Overrides rpath, an absolute rpath, and a delay-init library;
- compares the predicted load order of two process roots with what dyld
  loads under DYLD_PRINT_LIBRARIES.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-07 10:31:17 +00:00

168 lines
5.4 KiB
TypeScript

import { mkdir, writeFile } from "node:fs/promises";
import { dirname, join } from "node:path";
import { describe, expect } from "vitest";
import {
FILE_TYPE,
LC,
dylibCommand,
machoImage,
rpathCommand,
} from "../../../src/artifacts/MachoImage.fixture.js";
import { dylibResolutionResultSchema } from "../../../src/domain/dylibResolution.js";
import { createTestTempDirectory } from "../../fixtures/temporaryDirectory.js";
import { cliTest } from "../../support/cli/cliFixture.js";
const ENVIRONMENT = { REA_LOG_LEVEL: "silent", REA_ANALYSIS_PROVIDER: "auto" };
const writeFiles = async (
root: string,
files: Readonly<Record<string, string | Uint8Array>>,
): Promise<void> => {
for (const [path, content] of Object.entries(files)) {
await mkdir(dirname(join(root, path)), { recursive: true });
await writeFile(join(root, path), content);
}
};
const fixtureApp = async (): Promise<string> => {
const app = join(
await createTestTempDirectory("rea-dylib-cli-"),
"Fixture.app",
);
await writeFiles(app, {
"Contents/Info.plist":
"<plist><dict><key>CFBundleExecutable</key><string>App</string></dict></plist>",
"Contents/MacOS/App": machoImage({
commands: [
rpathCommand("@executable_path/../Frameworks"),
dylibCommand(LC.LOAD_DYLIB, "@rpath/libcore.dylib"),
dylibCommand(LC.LOAD_WEAK_DYLIB, "@rpath/libgone.dylib"),
],
}),
"Contents/Frameworks/libcore.dylib": machoImage({
fileType: FILE_TYPE.dylib,
commands: [dylibCommand(LC.ID_DYLIB, "@rpath/libcore.dylib")],
}),
"Contents/Helpers/tool": machoImage({
commands: [dylibCommand(LC.LOAD_DYLIB, "@loader_path/libnone.dylib")],
}),
});
return app;
};
describe("trace-dylib-resolution CLI", () => {
cliTest("traces every executable root of an app bundle", async ({ cli }) => {
const app = await fixtureApp();
const result = await cli.run({
arguments: ["trace-dylib-resolution", app, "--json"],
environment: ENVIRONMENT,
});
expect(result.exitCode, JSON.stringify(result.json)).toBe(0);
const trace = dylibResolutionResultSchema.parse(
(result.json as { normalized_result: unknown }).normalized_result,
);
expect(trace.root_path).toBe(app);
expect(trace.roots.map(({ image }) => image)).toEqual([
"Contents/Helpers/tool",
"Contents/MacOS/App",
]);
expect(
trace.edges.map(({ loader, install_name: name, resolution }) => [
loader,
name,
resolution.status,
resolution.image,
]),
).toEqual([
[
"Contents/Helpers/tool",
"@loader_path/libnone.dylib",
"unresolved",
null,
],
[
"Contents/MacOS/App",
"@rpath/libcore.dylib",
"resolved",
"Contents/Frameworks/libcore.dylib",
],
["Contents/MacOS/App", "@rpath/libgone.dylib", "unresolved", null],
]);
expect(trace.findings.map(({ kind }) => kind)).toEqual([
"required-load-unresolved",
"weak-load-unresolved",
]);
expect(
trace.images.every(({ sha256 }) => /^[0-9a-f]{64}$/u.test(sha256)),
).toBe(true);
});
cliTest(
"narrows roots and architecture, and rejects escaping roots",
async ({ cli }) => {
const app = await fixtureApp();
const narrowed = await cli.run({
arguments: [
"trace-dylib-resolution",
app,
"--root",
"Contents/MacOS/App",
"--architecture",
"arm64",
"--json",
],
environment: ENVIRONMENT,
});
expect(narrowed.exitCode).toBe(0);
expect(
(narrowed.json as { normalized_result: { roots: unknown } })
.normalized_result.roots,
).toEqual([{ image: "Contents/MacOS/App", architecture: "arm64" }]);
for (const root of ["../outside", "Contents/Info.plist"]) {
const rejected = await cli.run({
arguments: ["trace-dylib-resolution", app, "--root", root, "--json"],
environment: ENVIRONMENT,
});
expect(rejected.exitCode).toBe(1);
expect(rejected.json).toMatchObject({ error: "Analysis failed" });
}
},
);
cliTest(
"resolves a standalone Mach-O against its own directory",
async ({ cli }) => {
const directory = await createTestTempDirectory("rea-dylib-standalone-");
await writeFiles(directory, {
tool: machoImage({
commands: [
dylibCommand(LC.LOAD_DYLIB, "@loader_path/lib/libhelper.dylib"),
dylibCommand(LC.LOAD_DYLIB, "@loader_path/../escape.dylib"),
],
}),
"lib/libhelper.dylib": machoImage({ fileType: FILE_TYPE.dylib }),
"unrelated.txt": "not traversed",
});
const result = await cli.run({
arguments: [
"trace-dylib-resolution",
join(directory, "tool"),
"--json",
],
environment: ENVIRONMENT,
});
expect(result.exitCode, JSON.stringify(result.json)).toBe(0);
const trace = dylibResolutionResultSchema.parse(
(result.json as { normalized_result: unknown }).normalized_result,
);
expect(trace.roots).toEqual([{ image: "tool", architecture: "arm64" }]);
expect(trace.edges.map(({ resolution }) => resolution)).toEqual([
{ status: "resolved", image: "lib/libhelper.dylib" },
{ status: "undetermined", image: null },
]);
},
);
});