heaplab/HeapLAB/house_of_force/pwntools_template.py

#!/usr/bin/python3
from pwn import *

elf = context.binary = ELF("house_of_force")
libc = elf.libc

gs = '''
continue
'''
def start():
    if args.GDB:
        return gdb.debug(elf.path, gdbscript=gs)
    else:
        return process(elf.path)

# Select the "malloc" option, send size & data.
def malloc(size, data):
    io.send("1")
    io.sendafter("size: ", f"{size}")
    io.sendafter("data: ", data)
    io.recvuntil("> ")

# Calculate the "wraparound" distance between two addresses.
def delta(x, y):
    return (0xffffffffffffffff - x) + y

io = start()

# This binary leaks the address of puts(), use it to resolve the libc load address.
io.recvuntil("puts() @ ")
libc.address = int(io.recvline(), 16) - libc.sym.puts

# This binary leaks the heap start address.
io.recvuntil("heap @ ")
heap = int(io.recvline(), 16)
io.recvuntil("> ")
io.timeout = 0.1

# =============================================================================

# =-=-=- EXAMPLE -=-=-=

# The "heap" variable holds the heap start address.
log.info(f"heap: 0x{heap:02x}")

# Program symbols are available via "elf.sym.<symbol name>".
log.info(f"target: 0x{elf.sym.target:02x}")

# The malloc() function chooses option 1 from the menu.
# Its arguments are "size" and "data".
malloc(24, b"Y"*24)

# The delta() function finds the "wraparound" distance between two addresses.
log.info(f"delta between heap & main(): 0x{delta(heap, elf.sym.main):02x}")

# =============================================================================

io.interactive()