Initial commit.
This commit is contained in:
Maxim Poliakovski
commit
fff18e5866
|
|
@ -0,0 +1,267 @@
|
|||
'''
|
||||
Power Macintosh ROM disassembler.
|
||||
|
||||
Author: Max Poliakovski 2020-2021
|
||||
|
||||
Usage:
|
||||
python3 PowerRomDasm.py --rom_path=[path to a Power Macintosh ROM dump]
|
||||
'''
|
||||
from argparse import ArgumentParser
|
||||
from ruamel.yaml import YAML
|
||||
|
||||
from capstone import *
|
||||
from capstone.m68k import *
|
||||
|
||||
import struct
|
||||
|
||||
def bit_not(n, numbits=32):
|
||||
return (1 << numbits) - 1 - n
|
||||
|
||||
def align(n, m):
|
||||
return (n + m - 1) & bit_not(m - 1)
|
||||
|
||||
''' Capstone-based disassembler for 68k code.'''
|
||||
class M68KDasm:
|
||||
def __init__(self, cb):
|
||||
self.rom_cb = cb
|
||||
self.cse = Cs(CS_ARCH_M68K, CS_MODE_M68K_040)
|
||||
self.cse.detail = True
|
||||
self.labels = {}
|
||||
|
||||
def dasm_single(self, address, code):
|
||||
''' Disassble single 68k instruction with the Capstone engine. '''
|
||||
|
||||
# detect A-Traps and disassemble them ourselves
|
||||
if (code[0] & 0xF0) == 0xA0:
|
||||
from mactraps import TRAP_TABLE
|
||||
|
||||
trap_num = (code[0] << 8) | code[1]
|
||||
if trap_num in TRAP_TABLE:
|
||||
return ((TRAP_TABLE[trap_num], [], 2))
|
||||
else:
|
||||
return (('dc.w', [hex(trap_num)], 2))
|
||||
|
||||
# disassemble non-trap instructions with Capstone
|
||||
instrs = self.cse.disasm(code, address)
|
||||
return next(instrs)
|
||||
|
||||
def dasm_region(self, addr, size, data):
|
||||
pp_dasm = []
|
||||
last_addr = addr + size
|
||||
offset = 0
|
||||
|
||||
while addr < last_addr:
|
||||
# prefetch binary data (2 >= bytes <= 10) for the next instruction
|
||||
bin_length = min(last_addr - addr, 10)
|
||||
bin_prefetch = bytearray()
|
||||
for i in range(bin_length):
|
||||
bin_prefetch.append(data[offset+i])
|
||||
|
||||
instr = self.dasm_single(addr, bin_prefetch)
|
||||
|
||||
if not isinstance(instr, CsInsn):
|
||||
pp_dasm.append({'addr': addr, 'mnem': instr[0], 'ops': instr[1]})
|
||||
addr += instr[2]
|
||||
offset += instr[2]
|
||||
continue
|
||||
|
||||
op_list = instr.op_str.split(',')
|
||||
#print(op_list)
|
||||
ops = []
|
||||
for op in instr.operands:
|
||||
#print(op.type)
|
||||
if op.type == M68K_OP_MEM:
|
||||
#print(op.address_mode)
|
||||
if op.address_mode == M68K_AM_PCI_DISP:
|
||||
ea = addr + op.mem.disp + 2
|
||||
flag,sym = self.rom_cb.get_symbol(ea)
|
||||
if flag:
|
||||
ops.append(sym)
|
||||
else:
|
||||
label = 'l_{:x}'.format(ea)
|
||||
ops.append(label)
|
||||
if ea >= addr and ea < (addr + size):
|
||||
self.labels[ea] = label
|
||||
op_list.pop(0)
|
||||
elif op.address_mode == M68K_AM_PCI_INDEX_BASE_DISP:
|
||||
ops.append(instr.op_str)
|
||||
else:
|
||||
ops.append(op_list.pop(0))
|
||||
elif op.type == M68K_OP_BR_DISP:
|
||||
if op.address_mode == M68K_AM_BRANCH_DISPLACEMENT:
|
||||
ea = addr + op.br_disp.disp + 2
|
||||
flag,sym = self.rom_cb.get_symbol(ea)
|
||||
if flag:
|
||||
ops.append(sym)
|
||||
else:
|
||||
label = 'l_{:x}'.format(ea)
|
||||
ops.append(label)
|
||||
if ea >= addr and ea < (addr + size):
|
||||
self.labels[ea] = label
|
||||
op_list.pop(0)
|
||||
else:
|
||||
ops.append(op_list.pop(0))
|
||||
else:
|
||||
ops.append(op_list.pop(0))
|
||||
pp_dasm.append({'addr': addr, 'mnem': instr.mnemonic, 'ops': ops})
|
||||
addr += instr.size
|
||||
offset += instr.size
|
||||
#print(ops)
|
||||
#print(self.labels)
|
||||
for instr in pp_dasm:
|
||||
if instr['addr'] in self.labels:
|
||||
print('\n' + self.labels[instr['addr']] + ':')
|
||||
print(hex(instr['addr']).ljust(15), end='')
|
||||
print(instr['mnem'], '\t', end='')
|
||||
print(','.join(instr['ops']))
|
||||
|
||||
def dasm_regions(self, start_addr, size, data, regions):
|
||||
self.labels = {}
|
||||
for reg in regions:
|
||||
if reg[2] == 'align':
|
||||
print(hex(start_addr + reg[0]).ljust(15), end='')
|
||||
print('align\t' + str(reg[3]))
|
||||
elif reg[2] == 'code':
|
||||
reg_size = reg[1] - reg[0] + 1
|
||||
self.dasm_region(start_addr + reg[0], reg_size,
|
||||
data[reg[3]:reg[3]+reg_size])
|
||||
else:
|
||||
print("Unknown region type " + reg[2])
|
||||
|
||||
|
||||
class ROMDisassembler:
|
||||
def __init__(self, rom_data, rom_db):
|
||||
self.rom_data = rom_data
|
||||
self.rom_db = rom_db
|
||||
self.start_addr = rom_db['main_info']['phys_addr']
|
||||
self.m68k_dasm = M68KDasm(self)
|
||||
|
||||
def get_symbol(self, addr):
|
||||
offset = addr - self.start_addr
|
||||
if offset in self.rom_db['annot_items']:
|
||||
return (True, self.rom_db['annot_items'][offset]['label'])
|
||||
else:
|
||||
return (False, '')
|
||||
|
||||
def fmt_single_entry(self, format, size, offset):
|
||||
print(hex(self.start_addr + offset).ljust(15), end='')
|
||||
if format == 'hex':
|
||||
if size == 1:
|
||||
print("dc.b\t0x%X" % struct.unpack('>B', self.rom_data[offset:offset+1]))
|
||||
elif size == 2:
|
||||
print("dc.w\t0x%X" % struct.unpack('>H', self.rom_data[offset:offset+2]))
|
||||
elif size == 4:
|
||||
print("dc.l\t0x%X" % struct.unpack('>I', self.rom_data[offset:offset+4]))
|
||||
else:
|
||||
print("INVALID SIZE!")
|
||||
elif format == 'offset':
|
||||
dest_offset = struct.unpack('>I', self.rom_data[offset:offset+4])[0]
|
||||
if dest_offset in self.rom_db['annot_items']:
|
||||
symbol = self.rom_db['annot_items'][dest_offset]['label']
|
||||
print("dc.l\t" + symbol + '-BaseOfRom')
|
||||
else:
|
||||
print("dc.l\t0x%X" % dest_offset)
|
||||
|
||||
def parse_subregs(self, start, size, subregs):
|
||||
#print("This entry has subregions", subregs)
|
||||
regs = []
|
||||
reg_start = start
|
||||
for reg in subregs:
|
||||
if reg['type'] != 'align':
|
||||
print("Unknown subregion type " + reg['type'])
|
||||
return regs
|
||||
offset = reg['offset']
|
||||
if offset < reg_start or offset >= (start + size):
|
||||
print("Invalid subregion offset: 0x%X" % offset)
|
||||
return regs
|
||||
regs.append((reg_start, offset - 1, 'code', reg_start - start))
|
||||
boundary = reg['boundary']
|
||||
reg_end = align(offset, boundary)
|
||||
regs.append((offset, reg_end - 1, 'align', boundary))
|
||||
reg_start = reg_end
|
||||
if reg_start < (start + size):
|
||||
regs.append((reg_start, (start + size) - 1, 'code', reg_start - start))
|
||||
#print(regs)
|
||||
return regs
|
||||
|
||||
|
||||
def fmt_entry(self, entry, offset):
|
||||
print("")
|
||||
print((entry['label'] + ':').ljust(15))
|
||||
|
||||
if entry['type'] == 'array':
|
||||
count = entry['size'] // entry['elsize']
|
||||
for i in range(count):
|
||||
self.fmt_single_entry(entry['format'], entry['elsize'], offset)
|
||||
offset += entry['elsize']
|
||||
elif entry['type'] == 'int':
|
||||
self.fmt_single_entry(entry['format'], entry['size'], offset)
|
||||
elif entry['type'] == 'code':
|
||||
size = entry['size']
|
||||
if entry['arch'] == '68k':
|
||||
if 'subregs' in entry:
|
||||
regs = self.parse_subregs(offset, size, entry['subregs'])
|
||||
else:
|
||||
regs = [(offset, offset + size - 1, 'code', 0)]
|
||||
self.m68k_dasm.dasm_regions(self.start_addr, size,
|
||||
self.rom_data[offset:offset+size], regs)
|
||||
elif entry['arch'] == 'ppc':
|
||||
print("PPC disassembler not implemented yet")
|
||||
else:
|
||||
print("Unknown code region architecture " + entry['arch'])
|
||||
|
||||
def dasm_region(self, start, end):
|
||||
offset = start
|
||||
while offset < end:
|
||||
if offset in self.rom_db['annot_items']:
|
||||
entry = self.rom_db['annot_items'][offset]
|
||||
self.fmt_entry(entry, offset)
|
||||
offset += entry['size']
|
||||
else:
|
||||
print(hex(self.start_addr + offset).ljust(15), end='')
|
||||
print("dc.b\t0x%X" % struct.unpack('>B', self.rom_data[offset:offset+1]))
|
||||
offset += 1
|
||||
|
||||
|
||||
if __name__ == "__main__":
|
||||
parser = ArgumentParser()
|
||||
parser.add_argument('--rom_path', type=str,
|
||||
dest='rom_path',
|
||||
help='path to a PowerMacintosh ROM file to process',
|
||||
metavar='ROM_PATH', required=True)
|
||||
parser.add_argument('--start', type=lambda x: int(x,0),
|
||||
dest='start_offs', default=0,
|
||||
help='offset to the start of the region to disassemble',
|
||||
required=False,
|
||||
)
|
||||
parser.add_argument('--end', type=lambda x: int(x,0),
|
||||
dest='end_offs', default=0x500,
|
||||
help='offset to the end of the region to disassemble',
|
||||
required=False,
|
||||
)
|
||||
|
||||
opts = parser.parse_args()
|
||||
|
||||
with open(opts.rom_path, 'rb') as rom_file:
|
||||
rom_file.seek(0, 2)
|
||||
rom_size = rom_file.tell()
|
||||
if rom_size != (4 * 1024 * 1024):
|
||||
print("Invalid ROM file size %d (expected 4 MB)" % rom_size)
|
||||
|
||||
# just load the whole ROM image into memory
|
||||
rom_file.seek(0, 0)
|
||||
rom_data = rom_file.read()
|
||||
|
||||
check_sum = struct.unpack('>I', rom_data[0:4])[0]
|
||||
print("ROM Checksum: %X" % check_sum)
|
||||
|
||||
db_name = 'ROMDB_' + '{:x}'.format(int(check_sum)).upper() + '.yaml'
|
||||
|
||||
with open('database/' + db_name, 'rb') as db_file:
|
||||
yaml = YAML()
|
||||
annot_db = yaml.load(db_file)
|
||||
|
||||
print(annot_db['main_info']['name'])
|
||||
|
||||
rdasm = ROMDisassembler(rom_data, annot_db)
|
||||
rdasm.dasm_region(opts.start_offs, opts.end_offs)
|
||||
|
|
@ -0,0 +1,47 @@
|
|||
main_info:
|
||||
short_cksum: 0x9FEB69B3
|
||||
name: "Power Macintosh 6100, 7100 and 8100 ROM file"
|
||||
phys_addr: 0x40800000 # starting address of this ROM
|
||||
|
||||
annot_items:
|
||||
0: {type: int, format: hex, size: 4, label: BaseOfRom, comment: ROM checksum}
|
||||
4: {type: int, format: offset, size: 4, label: StartPC}
|
||||
8: {type: int, format: hex, size: 1, label: MachineType}
|
||||
9: {type: int, format: hex, size: 1, label: ROMVersion}
|
||||
0xA: {type: code, arch: 68k, size: 4, label: JStartBoot}
|
||||
0xE: {type: code, arch: 68k, size: 4, label: BadDisk}
|
||||
0x12: {type: int, format: hex, size: 2, label: ROMRelease}
|
||||
0x14: {type: int, format: hex, size: 2, label: PatchFlags}
|
||||
0x16: {type: int, format: offset, size: 4, label: ForeignOSVecT}
|
||||
0x1A: {type: int, format: offset, size: 4, label: RomRsrc}
|
||||
0x1E: {type: code, arch: 68k, size: 4, label: Eject}
|
||||
0x22: {type: int, format: offset, size: 4, label: DispOff}
|
||||
0x26: {type: code, arch: 68k, size: 4, label: Critical}
|
||||
0x2A: {type: code, arch: 68k, size: 4, label: ResetEntry}
|
||||
0x2E: {type: int, format: hex, size: 1, label: RomLoc}
|
||||
0x30: {type: array, format: hex, size: 16, elsize: 4, label: ROMCksum128}
|
||||
0x40: {type: int, format: hex, size: 4, label: ROMSize68k}
|
||||
0x44: {type: int, format: offset, size: 4, label: EraseMyIconOffs}
|
||||
0x48: {type: int, format: offset, size: 4, label: InitSys7ToolboxOffs}
|
||||
0x4E: {type: array, format: offset, size: 28, elsize: 4, label: ForeignOS}
|
||||
0x4C: {type: int, format: hex, size: 2, label: ROMSubRelease}
|
||||
0x6A: {type: code, arch: 68k, size: 6, label: GoofyDoEject}
|
||||
0x70: {type: int, format: hex, size: 4, label: TCOff}
|
||||
0x74: {type: code, arch: 68k, size: 0x70, label: StartBoot}
|
||||
0xE4:
|
||||
type: code
|
||||
arch: 68k
|
||||
size: 0x202
|
||||
label: StartInit1
|
||||
subregs:
|
||||
- type: align
|
||||
offset: 0x1f2
|
||||
boundary: 16
|
||||
- type: align
|
||||
offset: 0x236
|
||||
boundary: 16
|
||||
0x2E6: {type: code, arch: 68k, size: 0x1C2, label: BootRetry}
|
||||
0x4A8: {type: code, arch: 68k, size: 0x4E, label: WhichCPU}
|
||||
0x4F6: {type: code, arch: 68k, size: 0xC, label: WhichBoard}
|
||||
0x502: {type: code, arch: 68k, size: 0x100, label: SetUpTimeK}
|
||||
0x3A24A: {type: code, arch: 68k, size 4, label: DoEject}
|
||||
|
|
@ -0,0 +1,49 @@
|
|||
'''
|
||||
Provides a mapping from 68k traps to Macintosh traps names.
|
||||
|
||||
Author: Max Poliakovski 2020-2021
|
||||
'''
|
||||
TRAP_TABLE = {
|
||||
# trapN trap name
|
||||
0xA01B : "_SetZone",
|
||||
0xA01F : "_DisposePtr",
|
||||
0xA029 : "_HLock",
|
||||
0xA02D : "_SetApplLimit",
|
||||
0xA02E : "_BlockMove",
|
||||
0xA047 : "_SetTrapAddress",
|
||||
0xA04A : "_HNoPurge",
|
||||
0xA055 : "_StripAddress",
|
||||
0xA057 : "_SetAppBase",
|
||||
0xA064 : "_MoveHHi",
|
||||
0xA069 : "_HGetState",
|
||||
0xA06A : "_HSetState",
|
||||
0xA06C : "_InitFS",
|
||||
0xA0AD : "_GestaltDispatch",
|
||||
0xA0BD : "_CacheFlush",
|
||||
0xA11A : "_GetZone",
|
||||
0xA11E : "_NewPtr",
|
||||
0xA122 : "_NewHandle",
|
||||
0xA128 : "_RecoverHandle",
|
||||
0xA146 : "_GetTrapAddress",
|
||||
0xA162 : "_PurgeSpace",
|
||||
0xA1AD : "_Gestalt",
|
||||
0xA025 : "_GetHandleSize",
|
||||
0xA31E : "_NewPtrClear",
|
||||
0xA322 : "_NewHandleClear",
|
||||
0xA346 : "_GetOSTrapAddress",
|
||||
0xA51E : "_NewPtrSys",
|
||||
0xA522 : "_NewHandleSys",
|
||||
0xA71E : "_NewPtrSysClear",
|
||||
0xA722 : "_NewHandleSysClear",
|
||||
0xA746 : "_GetToolTrapAddress",
|
||||
0xA81F : "_Get1Resource",
|
||||
0xA820 : "_Get1NamedResource",
|
||||
0xA895 : "_ShutDown",
|
||||
0xA96E : "_Dequeue",
|
||||
0xA994 : "_CurResFile",
|
||||
0xA99B : "_SetResLoad",
|
||||
0xA9A0 : "_GetResource",
|
||||
0xA9A2 : "_LoadResource",
|
||||
0xA9AF : "_ResError",
|
||||
0xA9C9 : "_SysError",
|
||||
}
|
||||
Loading…
Reference in New Issue