From 5202ac214f8a35f151c0afba9323e4ae9586eef8 Mon Sep 17 00:00:00 2001
From: Cyrille Bagard <nocbos@gmail.com>
Date: Wed, 16 Jan 2019 18:54:09 +0100
Subject: Helped to track infinite recursions in rank computing.

---
 python/infrank.py | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 110 insertions(+)
 create mode 100644 python/infrank.py

diff --git a/python/infrank.py b/python/infrank.py
new file mode 100644
index 0000000..1b1bc29
--- /dev/null
+++ b/python/infrank.py
@@ -0,0 +1,110 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+
+import argparse
+import sys
+
+# from pychrysalide.features import *
+from pychrysalide.analysis.contents import FileContent
+from pychrysalide.analysis import StudyProject
+from pychrysalide.arch import ArchInstruction
+from pychrysalide.core import wait_for_all_global_works
+
+
+def init_fake_ranks(blocks):
+    """Build a list of ranks for basic blocks."""
+
+    ranks = {}
+
+    for b in blocks:
+        ranks[b] = -1
+
+    return ranks
+
+
+def dump_stack(stack):
+    """Print the stack of looping code blocks."""
+
+    for blk in stack:
+
+        print(' Loop detected:', blk.boundaries[0].range.addr)
+
+    sys.exit(2)
+
+
+def track_infinite_loop_when_ranking(blk, ranks, stack):
+    """Mimic the rank_routine_block() C function."""
+
+    fatal = blk in stack
+
+    stack.append(blk)
+
+    if fatal:
+        dump_stack(stack)
+
+    next_rank = ranks[blk] + 1
+
+    for dest, dtype in blk.destinations:
+
+        if dtype == ArchInstruction.ILT_LOOP:
+            continue
+
+        if dtype != ArchInstruction.ILT_EXEC_FLOW \
+           and dtype != ArchInstruction.ILT_JUMP \
+           and dtype != ArchInstruction.ILT_CASE_JUMP \
+           and dtype != ArchInstruction.ILT_JUMP_IF_TRUE \
+           and dtype != ArchInstruction.ILT_JUMP_IF_FALSE:
+            continue
+
+        if next_rank > ranks[blk] or ranks[blk] == -1:
+
+            ranks[dest] = next_rank
+
+            track_infinite_loop_when_ranking(dest, ranks, stack)
+
+    stack.remove(blk)
+
+
+if __name__ == '__main__':
+
+    title = '%s - Track infinite loops when computing ranks.' % sys.argv[0]
+    title += '\n\n'
+    title += '(this is a debug helper tool: call to rank_routine_blocks() should be disabled in src/analysis/disass/routines.c)'
+
+    parser = argparse.ArgumentParser(description=title, add_help=False, formatter_class=argparse.RawTextHelpFormatter)
+
+    parser.add_argument('-h', '--help', action='store_true', help='Display the command line options understood by %s.' % sys.argv[0])
+
+    parser.add_argument('binfile', type=str, help='The object file to be examined')
+    parser.add_argument('fname', type=str, help='The analyzed function to process')
+
+    args = parser.parse_args()
+
+    if args.help:
+        parser.print_help()
+        sys.exit(1)
+
+    prj = StudyProject()
+
+    cnt = FileContent(args.binfile)
+
+    prj.discover(cnt)
+
+    wait_for_all_global_works()
+
+    binary = prj.contents[0]
+
+    sym = binary.format.find_symbol_by_label(args.fname)
+
+    if not(sym):
+        print('Function "%s" not found!' % args.fname)
+        sys.exit(1)
+
+    blocks = list(sym.basic_blocks)
+
+    ranks = init_fake_ranks(blocks)
+
+    ranks[blocks[0]] = 0
+
+    track_infinite_loop_when_ranking(blocks[0], ranks, [])
-- 
cgit v0.11.2-87-g4458