Chomper is a lightweight emulation framework based on Unicorn. It is mainly used to emulate iOS executables and libraries. In addition, it also provides limited support for Android native libraries.
- Basic emulation for ELF and Mach-O
- Support for a set of iOS system libraries (from iOS 14.4.0)
- Python 3.8+
- Unicorn 2.0.0+
$ pip install chomper
Emulate iOS executables.
import uuid
from chomper import Chomper
from chomper.const import ARCH_ARM64, OS_IOS
# For iOS, system libraries will be automatically loaded from `rootfs_path`
emu = Chomper(
arch=ARCH_ARM64,
os_type=OS_IOS,
rootfs_path="examples/ios/rootfs",
)
# Load main program
duapp = emu.load_module("examples/ios/apps/com.siwuai.duapp/DUApp")
s = "chomper"
# Construct arguments
a1 = emu.create_string("objc")
a2 = emu.create_string(s)
a3 = len(s)
a4 = emu.create_string(str(uuid.uuid4()))
a5 = emu.create_buffer(8)
a6 = emu.create_buffer(8)
a7 = emu.create_string("com.siwuai.duapp")
# Call function
emu.call_address(duapp.base + 0x109322118, a1, a2, a3, a4, a5, a6, a7)
result = emu.read_string(emu.read_pointer(a5))
Working with Objective-C.
from chomper import Chomper
from chomper.const import ARCH_ARM64, OS_IOS
from chomper.objc import ObjC
emu = Chomper(
arch=ARCH_ARM64,
os_type=OS_IOS,
rootfs_path="examples/ios/rootfs",
)
objc = ObjC(emu)
emu.load_module("examples/ios/apps/cn.com.scal.sichuanair/zsch")
# Use this context manager to ensure that Objective-C objects can be automatically released
with objc.autorelease_pool():
# Construct NSString object
a1 = objc.msg_send("NSString", "stringWithUTF8String:", "test")
# Call Objective-C method
req_sign = objc.msg_send("ZSCHRSA", "getReqSign:", a1)
# Convert NSString object to C string
result_ptr = objc.msg_send(req_sign, "cStringUsingEncoding:", 4)
result = emu.read_string(result_ptr)
Emulate Android native libraries.
from chomper import Chomper
from chomper.const import ARCH_ARM64, OS_ANDROID
emu = Chomper(arch=ARCH_ARM64, os_type=OS_ANDROID)
# Load C standard and other libraries
emu.load_module("examples/android/rootfs/system/lib64/libc.so")
emu.load_module("examples/android/rootfs/system/lib64/libz.so")
libszstone = emu.load_module(
"examples/android/apps/com.shizhuang.duapp/libszstone.so",
exec_init_array=True,
)
s = "chomper"
a1 = emu.create_string(s)
a2 = len(s)
a3 = emu.create_buffer(1024)
result_size = emu.call_address(libszstone.base + 0x2F1C8, a1, a2, a3)
result = emu.read_bytes(a3, result_size)
Here are some encryption emulation examples for security vendors.