Squashed 'python/fsb5/' content from commit 5acfaed

git-subtree-dir: python/fsb5
git-subtree-split: 5acfaed9b44167eeebbd5f0414745cc23a2104a7

scripts/generate_vorbis_header_lookup.py

@@ -0,0 +1,101 @@
+#!/usr/bin/env python3
+
+import argparse
+import pefile
+import struct
+from pprint import pprint
+
+
+def main():
+	pp = argparse.ArgumentParser(description='Dump FSB5 vorbis headers from a 32-bit Windows executable')
+	pp.add_argument('file', help='path to executable file')
+	args = pp.parse_args()
+	pe = pefile.PE(args.file)
+	lookup = {}
+	base_addr = pe.OPTIONAL_HEADER.ImageBase
+
+	# reimplementation of get_memory_mapped_image because pefile did not survive
+	# the port to python 3 fully in tact...
+	mapped_data = pe.__data__[:]
+	for section in pe.sections:
+
+		# Miscellaneous integrity tests.
+		# Some packer will set these to bogus values to make tools go nuts.
+		if section.Misc_VirtualSize == 0 or section.SizeOfRawData == 0:
+			continue
+
+		if section.SizeOfRawData > len(pe.__data__):
+			continue
+
+		if pe.adjust_FileAlignment( section.PointerToRawData,
+			pe.OPTIONAL_HEADER.FileAlignment ) > len(pe.__data__):
+
+			continue
+
+		VirtualAddress_adj = pe.adjust_SectionAlignment( section.VirtualAddress,
+			pe.OPTIONAL_HEADER.SectionAlignment, pe.OPTIONAL_HEADER.FileAlignment )
+
+		padding_length = VirtualAddress_adj - len(mapped_data)
+
+		if padding_length>0:
+			mapped_data += b'\0'*padding_length
+		elif padding_length<0:
+			mapped_data = mapped_data[:padding_length]
+
+		mapped_data += section.get_data()
+
+	vas = []
+	va = 0
+	while True:
+		va = mapped_data.find(b'\x05vorbis', va)
+		if va > 0:
+			vas.append(base_addr + va)
+			va += 7
+		else:
+			break
+
+	refs = []
+	for va in vas:
+		word = struct.pack('<I', va)
+		ref = 0
+		while True:
+			ref = mapped_data.find(word, ref)
+			if ref > 0:
+				refs.append(base_addr + ref)
+				ref += 4
+			else:
+				break
+	refs.sort()
+
+	table_addr = 0
+	for ref in refs:
+		if (ref - 24 not in refs and ref - 12 not in refs) and (ref + 24 in refs or ref + 36 in refs):
+			table_addr = ref
+			break
+
+	if table_addr == 0:
+		raise
+
+	ea = table_addr
+	while True:
+		ea_ofs = ea - base_addr
+		buf1, len1, crc, buf2, ofs, len2 = struct.unpack('<IIIIII', mapped_data[ea_ofs:ea_ofs+0x18])
+		if crc == 0 or len1 == 0 or buf1 == 0 or len1 > 8192 or len2 > 8192:
+			break
+		hdr = bytearray(len1)
+		base_buf = buf1
+		if buf2 != 0:
+			base_buf = buf2
+		for j in range(len1):
+			hdr[j] = mapped_data[base_buf + j - base_addr]
+		if buf2 != 0:
+			for j in range(len2):
+				hdr[ofs+j] = mapped_data[buf1 + j - base_addr]
+		lookup[crc] = bytes(hdr)
+		ea += 24
+	print('lookup = ', end='')
+	pprint(lookup)
+
+
+if __name__ == '__main__':
+	main()