1 files changed, 119 insertions, 0 deletions
diff --git a/experiments/cfg_dump.py b/experiments/cfg_dump.py
new file mode 100644
index 0000000..30b6ba9
--- /dev/null
+++ b/experiments/cfg_dump.py
@@ -0,0 +1,119 @@
+#!/usr/bin/env python3
+"""Dump real basic-block CFGs to JSON, so graph-layout work can be done offline.
+
+Run with a python that has ``idapro`` (i.e. the worker python, /usr/bin/python3):
+
+    /usr/bin/python3 experiments/cfg_dump.py targets/echo -o /tmp/cfg-echo.json
+
+Copies the binary to a scratch dir first (never touches the tracked .i64), opens
+it with idalib, and writes one record per function:
+
+    {"name","ea","blocks":[{"id","start","end","lines":[str],"succs":[[id,kind]]}]}
+
+``kind`` is "fall" (falls through to the next address), "jump" (unconditional or
+taken branch) or "switch" (n-way). That is exactly the input a graph view needs;
+everything after this point (layering, ordering, routing, rendering) is pure
+python and needs no IDA at all.
+"""
+from __future__ import annotations
+
+import argparse
+import json
+import os
+import shutil
+import sys
+import tempfile
+
+
+def dump(path: str, want: list[str], max_blocks: int) -> list[dict]:
+    import idapro
+
+    scratch = tempfile.mkdtemp(prefix="cfgdump-")
+    local = os.path.join(scratch, os.path.basename(path))
+    shutil.copy2(path, local)
+    if idapro.open_database(local, run_auto_analysis=True) != 0:
+        raise SystemExit(f"failed to open {local}")
+
+    import ida_funcs
+    import ida_gdl
+    import ida_lines
+    import ida_bytes
+    import idautils
+    import idaapi
+
+    out = []
+    try:
+        for fea in idautils.Functions():
+            fn = ida_funcs.get_func(fea)
+            if not fn:
+                continue
+            name = ida_funcs.get_func_name(fea)
+            if want and not any(w in name for w in want):
+                continue
+            fc = ida_gdl.FlowChart(fn, flags=ida_gdl.FC_PREDS)
+            blocks = []
+            index = {}
+            for i, bb in enumerate(fc):
+                index[bb.start_ea] = i
+            for bb in fc:
+                lines = []
+                ea = bb.start_ea
+                while ea < bb.end_ea and ea != idaapi.BADADDR:
+                    txt = ida_lines.tag_remove(
+                        ida_lines.generate_disasm_line(ea, 0) or "")
+                    lines.append(txt.rstrip())
+                    nxt = ida_bytes.next_head(ea, bb.end_ea)
+                    if nxt <= ea:
+                        break
+                    ea = nxt
+                succs = []
+                sl = list(bb.succs())
+                for s in sl:
+                    if s.start_ea not in index:
+                        continue
+                    if len(sl) > 2:
+                        kind = "switch"
+                    elif s.start_ea == bb.end_ea:
+                        kind = "fall"
+                    else:
+                        kind = "jump"
+                    succs.append([index[s.start_ea], kind])
+                blocks.append({
+                    "id": index[bb.start_ea],
+                    "start": bb.start_ea,
+                    "end": bb.end_ea,
+                    "lines": lines,
+                    "succs": succs,
+                })
+            if max_blocks and len(blocks) > max_blocks:
+                continue
+            out.append({"name": name, "ea": fea, "blocks": blocks})
+    finally:
+        idapro.close_database(save=False)
+        shutil.rmtree(scratch, ignore_errors=True)
+    return out
+
+
+def main() -> int:
+    ap = argparse.ArgumentParser()
+    ap.add_argument("binary")
+    ap.add_argument("-o", "--out", default="/tmp/cfg.json")
+    ap.add_argument("-f", "--func", action="append", default=[],
+                    help="only functions whose name contains this (repeatable)")
+    ap.add_argument("--max-blocks", type=int, default=0,
+                    help="skip functions with more blocks than this")
+    args = ap.parse_args()
+
+    recs = dump(os.path.abspath(args.binary), args.func, args.max_blocks)
+    recs.sort(key=lambda r: len(r["blocks"]), reverse=True)
+    with open(args.out, "w") as f:
+        json.dump(recs, f)
+    tot = sum(len(r["blocks"]) for r in recs)
+    print(f"{len(recs)} functions, {tot} blocks -> {args.out}")
+    for r in recs[:12]:
+        print(f"  {len(r['blocks']):4d} blocks  {r['name']}")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())