You see the doors to the loading bay of the hangar, but they are locked. However, you are able to extract the password verification program from the control panel... Can you find the password to gain access to the loading bay?
解題鏈接： http://ctf5.shiyanbar.com/reverse/bitwise/bitwise.rar
題中給出了py代碼：
#!/usr/bin/env python
user_submitted = raw_input("Enter Password: ")
if len(user_submitted) != 10:
print "Wrong"
exit()
verify_arr = [193, 35, 9, 33, 1, 9, 3, 33, 9, 225]
user_arr = []
for char in user_submitted:
# '<<' is left bit shift
# '>>' is right bit shift
# '|' is bit-wise or
# '^' is bit-wise xor
# '&' is bit-wise and
user_arr.append( (((ord(char) << 5) | (ord(char) >> 3)) ^ 111) & 255 )
if (user_arr == verify_arr):
print "Success"
else:
print "Wrong"
于是 根據(jù)題的意思寫出了自己的解題腳本：
#!/usr/bin/env python3
verify_arr = [193, 35, 9, 33, 1, 9, 3, 33, 9, 225]
key=[0,0,0,0,0,0,0,0,0,0]
for i in range(10):
for k in range(128):
if verify_arr[i]==(((k<< 5) | (k >> 3)) ^ 111) & 255 :
key[i]=chr(k)
flag= ''
for i in key:
flag+=i
print flag
最終得到：
ub3rs3cr3t
技不如人就要多努力糯笙，假期已過，一切已是物是人非
