isle/tools/reccomp/reccomp.py
itsmattkc 290c006d14 use offsets from PDB to only diff instructions
Also ensure empty functions aren't falsely identified as matching due to no comparison occurring
2023-06-20 13:09:48 -07:00

346 lines
9.6 KiB
Python
Executable file

#!/usr/bin/env python3
from capstone import *
import difflib
import struct
import subprocess
import os
import sys
def print_usage():
print('Usage: %s [options] <original-binary> <recompiled-binary> <recompiled-pdb> <decomp-dir>\n' % sys.argv[0])
print('\t-v, --verbose <offset>\t\t\tPrint assembly diff for specific function (original file\'s offset)')
print('\t-h, --html <output-file>\t\t\tGenerate searchable HTML summary of status and diffs')
sys.exit(1)
positional_args = []
verbose = None
skip = False
html = None
for i, arg in enumerate(sys.argv):
if skip:
skip = False
continue
if arg.startswith('-'):
# A flag rather than a positional arg
flag = arg[1:]
if flag == 'v' or flag == '-verbose':
verbose = int(sys.argv[i + 1], 16)
skip = True
elif flag == 'h' or flag == '-html':
html = sys.argv[i + 1]
skip = True
else:
print('Unknown flag: %s' % arg)
print_usage()
else:
positional_args.append(arg)
if len(positional_args) != 5:
print_usage()
original = positional_args[1]
if not os.path.isfile(original):
print('Invalid input: Original binary does not exist')
sys.exit(1)
recomp = positional_args[2]
if not os.path.isfile(recomp):
print('Invalid input: Recompiled binary does not exist')
sys.exit(1)
syms = positional_args[3]
if not os.path.isfile(syms):
print('Invalid input: Symbols PDB does not exist')
sys.exit(1)
source = positional_args[4]
if not os.path.isdir(source):
print('Invalid input: Source directory does not exist')
sys.exit(1)
# Declare a class that can automatically convert virtual executable addresses
# to file addresses
class Bin:
def __init__(self, filename):
self.file = open(filename, 'rb')
#HACK: Strictly, we should be parsing the header, but we know where
# everything is in these two files so we just jump straight there
# Read ImageBase
self.file.seek(0xB4)
self.imagebase = struct.unpack('i', self.file.read(4))[0]
# Read .text VirtualAddress
self.file.seek(0x184)
self.textvirt = struct.unpack('i', self.file.read(4))[0]
# Read .text PointerToRawData
self.file.seek(0x18C)
self.textraw = struct.unpack('i', self.file.read(4))[0]
def __del__(self):
if self.file:
self.file.close()
def get_addr(self, virt):
return virt - self.imagebase - self.textvirt + self.textraw
def read(self, offset, size):
self.file.seek(self.get_addr(offset))
return self.file.read(size)
class RecompiledInfo:
addr = None
size = None
name = None
start = None
def get_wine_path(fn):
return subprocess.check_output(['winepath', '-w', fn]).decode('utf-8').strip()
def get_unix_path(fn):
return subprocess.check_output(['winepath', fn]).decode('utf-8').strip()
def get_file_in_script_dir(fn):
return os.path.join(os.path.dirname(os.path.abspath(sys.argv[0])), fn)
# Declare a class that parses the output of cvdump for fast access later
class SymInfo:
funcs = {}
lines = {}
def __init__(self, pdb, file):
call = [get_file_in_script_dir('cvdump.exe'), '-l', '-s']
if os.name != 'nt':
# Run cvdump through wine and convert path to Windows-friendly wine path
call.insert(0, 'wine')
call.append(get_wine_path(pdb))
else:
call.append(pdb)
print('Parsing %s...' % pdb)
line_dump = subprocess.check_output(call).decode('utf-8').split('\r\n')
current_section = None
for i, line in enumerate(line_dump):
if line.startswith('***'):
current_section = line[4:]
if current_section == 'SYMBOLS' and 'S_GPROC32' in line:
addr = int(line[26:34], 16)
debug_offs = line_dump[i + 2]
debug_start = int(debug_offs[22:30], 16)
debug_end = int(debug_offs[43:], 16)
info = RecompiledInfo()
info.addr = addr + recompfile.imagebase + recompfile.textvirt
info.start = debug_start
info.size = debug_end - debug_start
info.name = line[77:]
self.funcs[addr] = info
elif current_section == 'LINES' and line.startswith(' ') and not line.startswith(' '):
sourcepath = line.split()[0]
if os.name != 'nt':
# Convert filename to Unix path for file compare
sourcepath = get_unix_path(sourcepath)
if sourcepath not in self.lines:
self.lines[sourcepath] = {}
j = i + 2
while True:
ll = line_dump[j].split()
if len(ll) == 0:
break
k = 0
while k < len(ll):
linenum = int(ll[k + 0])
address = int(ll[k + 1], 16)
if linenum not in self.lines[sourcepath]:
self.lines[sourcepath][linenum] = address
k += 2
j += 1
def get_recompiled_address(self, filename, line):
addr = None
found = False
#print('Looking for ' + filename + ' line ' + str(line))
for fn in self.lines:
# Sometimes a PDB is compiled with a relative path while we always have
# an absolute path. Therefore we must
if os.path.samefile(fn, filename):
filename = fn
break
if filename in self.lines and line in self.lines[fn]:
addr = self.lines[fn][line]
if addr in self.funcs:
return self.funcs[addr]
else:
print('Failed to find function symbol with address: %s' % hex(addr))
else:
print('Failed to find function symbol with filename and line: %s:%s' % (filename, str(line)))
origfile = Bin(original)
recompfile = Bin(recomp)
syminfo = SymInfo(syms, recompfile)
print()
md = Cs(CS_ARCH_X86, CS_MODE_32)
def sanitize(file, mnemonic, op_str):
offsetplaceholder = '<OFFSET>'
if mnemonic == 'call' or mnemonic == 'jmp':
# Filter out "calls" because the offsets we're not currently trying to
# match offsets. As long as there's a call in the right place, it's
# probably accurate.
op_str = offsetplaceholder
else:
def filter_out_ptr(ptype, op_str):
try:
ptrstr = ptype + ' ptr ['
start = op_str.index(ptrstr) + len(ptrstr)
end = op_str.index(']', start)
# This will throw ValueError if not hex
inttest = int(op_str[start:end], 16)
return op_str[0:start] + offsetplaceholder + op_str[end:]
except ValueError:
return op_str
# Filter out dword ptrs where the pointer is to an offset
op_str = filter_out_ptr('dword', op_str)
op_str = filter_out_ptr('word', op_str)
op_str = filter_out_ptr('byte', op_str)
# Use heuristics to filter out any args that look like offsets
words = op_str.split(' ')
for i, word in enumerate(words):
try:
inttest = int(word, 16)
if inttest >= file.imagebase + file.textvirt:
words[i] = offsetplaceholder
except ValueError:
pass
op_str = ' '.join(words)
return mnemonic, op_str
def parse_asm(file, addr, size):
asm = []
data = file.read(addr, size)
for i in md.disasm(data, 0):
# Use heuristics to disregard some differences that aren't representative
# of the accuracy of a function (e.g. global offsets)
mnemonic, op_str = sanitize(file, i.mnemonic, i.op_str)
if op_str is None:
asm.append(mnemonic)
else:
asm.append("%s %s" % (mnemonic, op_str))
return asm
function_count = 0
total_accuracy = 0
htmlinsert = []
for subdir, dirs, files in os.walk(source):
for file in files:
srcfilename = os.path.join(os.path.abspath(subdir), file)
srcfile = open(srcfilename, 'r')
line_no = 0
while True:
try:
line = srcfile.readline()
line_no += 1
if not line:
break
if line.startswith('// OFFSET:'):
par = line[10:].strip().split()
module = par[0]
addr = int(par[1], 16)
find_open_bracket = line
while '{' not in find_open_bracket:
find_open_bracket = srcfile.readline()
line_no += 1
recinfo = syminfo.get_recompiled_address(srcfilename, line_no)
if not recinfo:
continue
if recinfo.size:
origasm = parse_asm(origfile, addr + recinfo.start, recinfo.size)
recompasm = parse_asm(recompfile, recinfo.addr + recinfo.start, recinfo.size)
diff = difflib.SequenceMatcher(None, origasm, recompasm)
ratio = diff.ratio()
else:
ratio = 0
print(' %s (%s / %s) is %.2f%% similar to the original' % (recinfo.name, hex(addr), hex(recinfo.addr), ratio * 100))
function_count += 1
total_accuracy += ratio
if recinfo.size:
if verbose == addr or html:
udiff = difflib.unified_diff(origasm, recompasm)
if verbose == addr:
for line in udiff:
print(line)
print()
print()
if html:
htmlinsert.append('{address: "%s", name: "%s", matching: %s, diff: "%s"}' % (hex(addr), recinfo.name, str(ratio), '\\n'.join(udiff).replace('"', '\\"').replace('\n', '\\n')))
except UnicodeDecodeError:
break
def gen_html(html, data):
templatefile = open(get_file_in_script_dir('template.html'), 'r')
if not templatefile:
print('Failed to find HTML template file, can\'t generate HTML summary')
return
templatedata = templatefile.read()
templatefile.close()
templatedata = templatedata.replace('/* INSERT DATA HERE */', ','.join(data), 1)
htmlfile = open(html, 'w')
if not htmlfile:
print('Failed to write to HTML file %s' % html)
return
htmlfile.write(templatedata)
htmlfile.close()
if html:
gen_html(html, htmlinsert)
if function_count > 0:
print('\nTotal accuracy %.2f%% across %i functions' % (total_accuracy / function_count * 100, function_count))