dxc.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import argparse
import math

import gdb

import pwndbg.arch
import pwndbg.commands
import pwndbg.memory
from pwndbg.commands.windbg import get_type


parser = argparse.ArgumentParser(description="Starting at the specified address, dump N bytes as code.")
parser.add_argument("address", type=pwndbg.commands.HexOrAddressExpr, help="The address to dump from.")
parser.add_argument("count", type=pwndbg.commands.AddressExpr, default=64, nargs="?", help="The number of bytes to dump.")
@pwndbg.commands.ArgparsedCommand(parser)
@pwndbg.commands.OnlyWhenRunning
def dbc(address, count=64):
    """
    Starting at the specified address, dump N bytes
    as code(default 64).
    """
    return dXc(1, address, count, repeat=dbc.repeat)

parser = argparse.ArgumentParser(description="Starting at the specified address, dump N words as code.")
parser.add_argument("address", type=pwndbg.commands.HexOrAddressExpr, help="The address to dump from.")
parser.add_argument("count", type=pwndbg.commands.AddressExpr, default=64, nargs="?", help="The number of words to dump.")
@pwndbg.commands.ArgparsedCommand(parser)
@pwndbg.commands.OnlyWhenRunning
def dwc(address, count=32):
    """
    Starting at the specified address, dump N words
    as code(default 32).
    """
    return dXc(2, address, count, repeat=dbc.repeat)


parser = argparse.ArgumentParser(description="Starting at the specified address, dump N dwords as code.")
parser.add_argument("address", type=pwndbg.commands.HexOrAddressExpr, help="The address to dump from.")
parser.add_argument("count", type=pwndbg.commands.AddressExpr, default=64, nargs="?", help="The number of dwords to dump.")
@pwndbg.commands.ArgparsedCommand(parser)
@pwndbg.commands.OnlyWhenRunning
def ddc(address, count=16):
    """
    Starting at the specified address, dump N dwords
    as code(default 16).
    """
    return dXc(4, address, count, repeat=dbc.repeat)


parser = argparse.ArgumentParser(description="Starting at the specified address, dump N qwords as code.")
parser.add_argument("address", type=pwndbg.commands.HexOrAddressExpr, help="The address to dump from.")
parser.add_argument("count", type=pwndbg.commands.AddressExpr, default=64, nargs="?", help="The number of qwords to dump.")
@pwndbg.commands.ArgparsedCommand(parser)
@pwndbg.commands.OnlyWhenRunning
def dqc(address, count=8):
    """
    Starting at the specified address, dump N qwords
    as code(default 8).
    """
    return dXc(8, address, count, repeat=dbc.repeat)


def dXc(size, address, count, repeat=False):
    values = []

    if repeat:
        count = dXc.last_count + dXc.step
        address = dXc.address
    else:
        address = int(address) & pwndbg.arch.ptrmask
        count = int(count)

    type = get_type(size)

    for i in range(count):
        try:
            gval = pwndbg.memory.poi(type, address + i * size)
            # print(str(gval))
            values.append(int(gval))
        except gdb.MemoryError:
            break

    if not values:
        print('Could not access the provided address')
        return

    n_rows = int(math.ceil(count * size / float(16)))
    row_sz = int(16 / size)
    rows   = [values[i*row_sz:(i+1)*row_sz] for i in range(n_rows)]
    lines  = []

    # sys.stdout.write(repr(rows) + '\n')

    for i, row in enumerate(rows):
        if not row:
            continue
        line = []
        for value in row:
            line.append(tohex(size, value))
        lines.append(', '.join(line))

    print(',\n'.join(lines))

    dXc.last_count = count
    dXc.step = count
    dXc.address = address
    return lines


def tohex(size, value):
    value = value & pwndbg.arch.ptrmask
    return f'0x{value:0{size*2}x}'