Lazy python wrapper of KLEE for solving CTF challenges.
- Install Docker
docker pull klee/klee
usage: LazyKLEE.py [-h] [-v] [-i] [-o] [-l] [-p] [-w] [-c CLANG_ARGS]
[-k KLEE_ARGS] [-a ARGS]
src
positional arguments:
src source code
optional arguments:
-h, --help show this help message and exit
-v, --verbose show verbose message
-i, --interact interact with container after running KLEE
-o, --optimize run KLEE with -optimize
-l, --libc run KLEE with -libc=uclibc
-p, --posix run KLEE with -posix-runtime
-w, --write-ints convert 4-byte sequences to integers in ktest-tool
-c CLANG_ARGS, --clang-args CLANG_ARGS
additional arguments for clang
-k KLEE_ARGS, --klee-args KLEE_ARGS
additional arguments for KLEE
-a ARGS, --args ARGS additional arguments for target program- Decompile binary to source code with hex-rays
- Include
defs.hfrom plugins folder of IDA Pro - Replace
read(stdin, input, sizeof(input));withklee_make_symbolic(input, sizeof(input), "input"); - Replace
print_flag();withklee_assert(0); LazyKLEE.py solve.c, add--libcif any libc functions used
$ LazyKLEE.py ~/CTF/defcon_2017/crackme1/solve.c
=== LazyKLEE ===
[+] Creating container...
[+] Compiling llvm bitcode...
Auto include klee/klee.h
Auto include assert.h
[+] Running KLEE...
[!] ASSERTION triggered!
ktest file : './klee-last/test000032.ktest'
args : ['solve.bc']
num objects: 1
object 0: name: b'input'
object 0: size: 80
object 0: data: b'yes and his hands shook with ex\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
[+] Removing container...