angr 03_angr_symbolic_registers 寄存器符号化

Posted 2023-02-20 漫小牛

文章目录

• • 1 解题过程

03_angr_simbolic_registers是angr的第4个例子，下载位置：https://github.com/jakespringer/angr_ctf

1 解题过程

import angr
import sys 
import claripy

def main(argv):
    bin_path = argv[1]
    p = angr.Project(bin_path)

    start_addr = 0x08048980                                                                                                                       
    init_state = p.factory.blank_state(addr=start_addr)

#新建 符号向量
    pass1 = claripy.BVS('pass1', 32) 
    pass2 = claripy.BVS('pass2', 32) 
    pass3 = claripy.BVS('pass3', 32) 

    init_state.regs.eax = pass1
    init_state.regs.ebx = pass2
    init_state.regs.edx = pass3

    sm = p.factory.simulation_manager(init_state)

    def is_good(state):
        return b'Good Job' in state.posix.dumps(1)

    def is_bad(state):
        return b'Try again' in state.posix.dumps(1)

    sm.explore(find=is_good, avoid=is_bad)

    if sm.found:
        found_state = sm.found[0]

        password1 = found_state.solver.eval(pass1)
        password2 = found_state.solver.eval(pass2)
        password3 = found_state.solver.eval(pass3)
#       print("Solution:   ".format(password1, password2, password3))
        print("Solution: :x :x :x".format(password1, password2, password3))
    else:
        raise Exception("No solution found")

if __name__ == '__main__':
    main(sys.argv)               

执行如下命令：

python 03.py 03_angr_symbolic_registers

得到solution：

Solution: b9ffd04e ccf63fe8 8fd4d959

将该Solution作为程序的输入，经验证无误：

(angr) dist$ ./03_angr_symbolic_registers           
Enter the password: b9ffd04e ccf63fe8 8fd4d959
Good Job.