OpenMaidEngine/tools/frida

Frida runtime-observation tools

Runtime instrumentation of the live game (AGE.EXE) to capture ground truth for the subsystems that have no static/machine oracle — asset resolution, graphics, audio, and the opaque effectful opcodes. Frida attaches to the running (unpacked-in-memory) process, so the game's packer is bypassed for hooking.

Prereq: py -3.11 -m pip install frida (core only — frida-tools CLI is not needed and its pygments shim fails to install in this env). Installed: frida 17.15.3.

Standard workflow

1. Launch the game (via AGE Patch.exe to avoid the periodic system-check messagebox) to a safe point (e.g. the title). Attach after launch, not frida -f — spawning the patcher wouldn't hook its child AGE.EXE, and direct-spawn risks the messagebox.
2. Run the capture script (py -3.11 -u -X utf8 tools/frida/<tool>.py) — it attaches by process name and installs the hooks; run unbuffered (-u) so status prints appear immediately.
3. Drive the game through the target scene (SC0000's opening auto-plays on new game).
4. Stop the script; analyse the log in build/ and order-correlate with the engine's op sequence (e.g. vm0/the C# recording host's set-texture/play-voice order for that scene).

Tools

• dump_engine.py — ★ dumps the unpacked engine code from the live process for offline static RE (native op handlers). Both on-disk images are the same packed binary (SYS4AB.BIN = XOR-0xFF of AGE.EXE), so the real handler code exists only in memory: the AGE.EXE module (some code unpacked in-place, e.g. the AGF decoder +0x74f1f) plus the main VM interpreter in a large per-run heap r-x region (~30 MB, nonstable base). Attach → it enumerates ranges, dumps the module image + every r-x range ≥ 1 MB (chunked) → build/engine-dump/{manifest.json,range_<base>.bin}, and prints the landmark bytes at AGE.EXE+0x74f1f to validate. Then disassemble (capstone) and locate a handler (e.g. 0x215 @ Kelebek VA 0x421160) via the opcode dispatch table. Attach by pid.
• capture_load_order.py — ★ the working asset-resolution capture. Hooks ReadFile on DATA2.ALF; each asset load starts with header reads at its exact archive offset, so exact-start reads give the clean per-asset load order (→ names via build/asset-index.json). --analyze prints the order + file_number. This confirmed resId == SYS4INI file_number (the load order matches our engine's set-texture(resId) order 1:1). Attach by pid, replay the scene, Ctrl-C, --analyze.
• capture_graphics.py — original ReadFile logger for DATA2/DATA5 (path<TAB>offset<TAB>size → build/frida-reads.log); pair with tools/resolve_frida_reads.py.
• locate_resource_load.py — phase-1 locator (back-trace asset-opens → native load chain).
• capture_resid_args.py — phase-2 probe (decoder args/context; showed the loader carries only offsets).
• find_globals_base.py, find_global_by_sequence.py — runtime global-variable RE (SHELVED). Full write-up, findings, memory landmarks, and the recommended resume plan: docs/global-memory-re.md. TL;DR: the VM global memory is structured/multi-store (not flat int32) and G[0x62424] is a transient arg-register — heuristic value scans can't pin it. Resume from a stable anchor (the name global 0x279) and target the interpreter's address resolution, not scans.

Runtime architecture (learned 2026-07-06 — read before writing new hooks)

• Attach, don't spawn, and use the pid (frida.get_local_device().enumerate_processes() — the module-level frida.enumerate_processes() was removed in frida 17.x). The process is AGE.EXE.
• The game is packed. Its main VM logic runs from a per-run heap r-x region (~30 MB, nonstable base). So you cannot hook the set-texture/VM handlers at a fixed AGE.EXE+off — only stable library code (e.g. the AGF decoder AGE.EXE+0x74f1f) keeps a fixed offset.
• Archives are NOT memory-mapped. No archive-sized region exists; the game streams them through a small heap block-cache via ReadFile (128 KB blocks + big reads). The earlier "memory-mapped" note was wrong — the 128 KB reads are the block cache, not OS paging.
• The reliable oracle is the ReadFile offset stream → names via the SYS4INI index (tools/parse_sys4ini.py → build/asset-index.json). Native-handler hooking is blocked by the packer.