Files
OpenFUT/fifa17-recon/tools/ghidra_env.py
T
funman300 397d46f174 fifa17-recon: the -4 rule is literally the ASCII prefix "RS4:"
The "4-byte header" that precedes every response class name in .rdata, which cost six
failed class-to-deserializer resolutions before anyone noticed the offset, is not a
length prefix or a refcount. It is the string RS4:. The full literal is
RS4:FutXServerResponse, and searching for the bare class name lands four bytes in.

Verified directly on three classes:
  FutDestroyMatchServerResponse           name@0x18021d694  header = b'RS4:'
  FutGetDraftCurrentStateServerResponse   name@0x180224204  header = b'RS4:'
  FutStickerBookStats2ServerResponse      name@0x1802220cc  header = b'RS4:'

Found by a verification agent that had been instructed to distrust the rule. It did,
and came back with the reason rather than the offset. A magic constant you have to
remember is a rule you will eventually get wrong; a prefix you can read is not.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VUT92pz6RWKih9dSr8ZpxW
2026-08-04 13:48:14 -07:00

246 lines
9.0 KiB
Python

#!/usr/bin/env python3
"""OpenFUT Ghidra helper: opens the analysed cardsdll.dll program once and exposes
decompile / xref / vtable helpers, so each RE question is a small python file
instead of a JVM restart + OSGi compile.
Usage: ghidra_env.py <query.py> -- runs <query.py> with the helpers in scope
(see tools/ghidra_queries/ for worked examples)
WHY PYGHIDRA: this box's Ghidra 12.1.2 cannot compile .java scripts at all --
analyzeHeadless -postScript Foo.java dies with "Failed to get OSGi bundle
containing script" for EVERY script, including ones that ran before (it is the
in-process OSGi/javac path that is broken, not the scripts). PyGhidra bypasses it.
Setup once:
python3 -m venv gvenv
gvenv/bin/pip install --no-index \
--find-links /opt/ghidra/Ghidra/Features/PyGhidra/pypkg/dist pyghidra
gvenv/bin/python ghidra_env.py <query.py>
Two traps this file already works around:
* open_program(..., nested_project_location=False) -- otherwise pyghidra creates
a NEW empty project at <loc>/<name>/ and re-imports (losing the analysis).
* os._exit(0) at the end -- JVM teardown under jpype deadlocks forever.
* read_bytes() uses a Java byte[]; passing a Python bytearray to Memory.getBytes
silently reads NOTHING and every scan comes back with 0 hits.
"""
import os, sys
os.environ.setdefault("GHIDRA_INSTALL_DIR", "/opt/ghidra")
import pyghidra
pyghidra.start(verbose=False)
from ghidra.app.decompiler import DecompInterface # noqa: E402
from ghidra.util.task import ConsoleTaskMonitor # noqa: E402
# Defaults target CardsDLL; override for another binary, e.g. powdll (the EASFC/POW
# layer, which is UNPACKED unlike FIFA17.exe):
# GHIDRA_DLL=/tmp/pow/powdll_Win64_retail.dll GHIDRA_PROJ_DIR=/tmp/pow \
# GHIDRA_PROJ=powproj ghidra_env.py <query.py>
DLL = os.environ.get("GHIDRA_DLL", "/tmp/fut/cardsdll.dll")
PROJ_DIR = os.environ.get("GHIDRA_PROJ_DIR", "/tmp/ghidra_fut")
PROJ = os.environ.get("GHIDRA_PROJ", "cardsdll")
PROG = os.environ.get("GHIDRA_PROG", os.path.basename(DLL))
# nested_project_location=False -> use /tmp/ghidra_fut/cardsdll.gpr itself (the
# already-analysed project) instead of creating /tmp/ghidra_fut/cardsdll/.
_ctx = pyghidra.open_program(DLL, project_location=PROJ_DIR, project_name=PROJ,
analyze=False, program_name=PROG,
nested_project_location=False)
flat = _ctx.__enter__()
prog = flat.getCurrentProgram()
mon = ConsoleTaskMonitor()
fm = prog.getFunctionManager()
listing = prog.getListing()
mem = prog.getMemory()
refs = prog.getReferenceManager()
_dec = DecompInterface()
_dec.openProgram(prog)
def addr(a):
return prog.getAddressFactory().getDefaultAddressSpace().getAddress(int(a))
def func(a):
return fm.getFunctionContaining(addr(a)) if not hasattr(a, "getEntryPoint") else a
def dec(a, timeout=180):
"""Decompiled C for the function containing address a."""
f = func(a)
if f is None:
return "// no function at %#x" % int(a)
r = _dec.decompileFunction(f, timeout, mon)
if r is None or not r.decompileCompleted():
return "// decompile failed for %s" % f.getName()
return str(r.getDecompiledFunction().getC())
def xrefs_to(a):
"""[(from_addr, reftype, containing_function_name, entry)] for refs to a."""
out = []
it = refs.getReferencesTo(addr(a))
while it.hasNext():
r = it.next()
f = fm.getFunctionContaining(r.getFromAddress())
out.append((int(r.getFromAddress().getOffset()), str(r.getReferenceType()),
f.getName() if f else "?",
int(f.getEntryPoint().getOffset()) if f else 0))
return out
def qword(a):
return mem.getLong(addr(a)) & 0xFFFFFFFFFFFFFFFF
def dword(a):
return mem.getInt(addr(a)) & 0xFFFFFFFF
import jpype # noqa: E402
_JBYTE = jpype.JArray(jpype.JByte)
def read_bytes(a, n):
"""Bulk read n bytes at a. MUST use a Java byte[] -- passing a Python
bytearray to Memory.getBytes silently reads nothing (this bug quietly
zeroed several earlier scans)."""
buf = _JBYTE(int(n))
got = mem.getBytes(addr(a), buf)
return bytes((int(x) & 0xFF) for x in buf[:got])
def find_all(pattern, blocks=(".text", ".rdata", ".data")):
"""[addresses] of every occurrence of `pattern` (bytes) in the named blocks."""
hits = []
for b in mem.getBlocks():
if b.getName() not in blocks or not b.isInitialized():
continue
s = int(b.getStart().getOffset())
size = int(b.getEnd().getOffset()) - s + 1
off = 0
chunk = 1 << 20
while off < size:
ln = min(chunk, size - off)
try:
data = read_bytes(s + off, ln)
except Exception:
off += ln
continue
i = data.find(pattern)
while i != -1:
hits.append(s + off + i)
i = data.find(pattern, i + 1)
off += ln - (len(pattern) - 1) if ln == chunk else ln
return hits
def rd_str(a, maxlen=200):
b = bytearray()
p = int(a)
for _ in range(maxlen):
c = mem.getByte(addr(p)) & 0xFF
if c == 0:
break
b.append(c)
p += 1
return b.decode("utf-8", "replace")
def vtable(a, n=64):
"""[(slot_offset, target_addr, function_name)] reading n qwords at a."""
out = []
for i in range(n):
try:
t = qword(int(a) + i * 8)
except Exception:
break
f = fm.getFunctionAt(addr(t)) if 0x180000000 <= t < 0x181000000 else None
out.append((i * 8, t, f.getName() if f else ""))
return out
def class_deser(cls):
"""FutXServerResponse class name -> [(deserializer, vtable, factory), ...].
THE -4 RULE, AND WHAT IT ACTUALLY IS. A response class's name literal is
preceded by a 4-byte header, and the factory's `lea r8,[rip+...]` points at
THAT header, not at the text, so the reference to look up is `name_addr - 4`.
Six attempts at class->deser resolution failed before this was noticed; four of
them returned zero candidates and were nearly written up as "the class has no
deserializer". Ghidra does create the reference, so no manual instruction
decoding is needed.
The "4-byte header" is not a length prefix or a refcount. It is literally the
ASCII string `RS4:`. The full literal is `RS4:FutXServerResponse`, and searching
for the bare class name lands four bytes into it. Knowing that, the rule stops
being a magic constant to remember and becomes obvious, and it also means you
can search for `RS4:` + the class name directly and skip the arithmetic.
(Established 2026-08-04 by a verification agent that had been told to distrust
the rule; it did, and found the reason instead of the offset.)
From the factory, the object's vtable is the .rdata address it references whose
first two qwords are functions; the deserializer is vtable slot +0x08.
Verified against known-good controls: FutSquadSave -> 0x180171a60,
FutSquadList -> 0x180172140, FutCreateMatch -> 0x180120380 (3/3 correct when it
resolves). It DOES produce false negatives -- FutDestroyMatch and
FutSeasonLoadData return nothing despite having known deserializers -- so treat
an empty result as "unknown", never as "no deserializer exists". Always include
a control with a known answer in any batch.
"""
res = []
for a in find_all(cls.encode() + b"\x00"):
for frm, typ, fn, ent in xrefs_to(a - 4):
if not ent:
continue
f = func(ent)
if f is None:
continue
for ad in f.getBody().getAddresses(True):
ins = listing.getInstructionAt(ad)
if ins is None:
continue
for r in ins.getReferencesFrom():
t = int(r.getToAddress().getOffset())
if not (0x1801E5000 <= t <= 0x1802891FF):
continue
try:
v0, v1 = qword(t), qword(t + 8)
except Exception:
continue
if (fm.getFunctionAt(addr(v0)) and fm.getFunctionAt(addr(v1))):
res.append((v1, t, ent))
return res
def fname(a):
f = func(a)
return f.getName() if f else "?"
def callees(a):
f = func(a)
return sorted({(int(c.getEntryPoint().getOffset()), c.getName())
for c in f.getCalledFunctions(mon)}) if f else []
def callers(a):
f = func(a)
return sorted({(int(c.getEntryPoint().getOffset()), c.getName())
for c in f.getCallingFunctions(mon)}) if f else []
if __name__ == "__main__":
if len(sys.argv) > 1:
g = dict(globals())
g["__name__"] = "__main__"
exec(open(sys.argv[1]).read(), g)
else:
print("loaded:", prog.getName(), fm.getFunctionCount(), "functions")
sys.stdout.flush()
# JVM teardown deadlocks under jpype here -- skip it, all output is flushed.
os._exit(0)