|
#!/usr/bin/env python2
|
|
import dis
|
|
import sys
|
|
|
|
# Original function
|
|
def check_password(s):
|
|
good = '4e5d4e92865a4e495a86494b5a5d49525261865f5758534d4a89'.decode('hex')
|
|
if len(s) != len(good):
|
|
return False
|
|
|
|
return all([ord(cs) - 89 & 255 ^ 115 ^ 50 == ord(cg) for cs, cg in zip(s, good)])
|
|
|
|
# Cracking the password
|
|
pass_values = {}
|
|
for i in range(256):
|
|
result = i - 89 & 255 ^ 115 ^ 50
|
|
pass_values[result] = i
|
|
|
|
good = '4e5d4e92865a4e495a86494b5a5d49525261865f5758534d4a89'.decode('hex')
|
|
password = ''
|
|
for c in good:
|
|
password += chr(pass_values[ord(c)])
|
|
|
|
print(password)
|
|
print(check_password(password))
|
|
# exit(0)
|
|
|
|
# Reverse engineering the code
|
|
cnames = ('co_argcount', 'co_consts', 'co_flags', 'co_name', 'co_names', 'co_nlocals', 'co_stacksize', 'co_varnames')
|
|
cvalues = (1, (None, '4e5d4e92865a4e495a86494b5a5d49525261865f5758534d4a89', 'hex', 89, 255, 115, 50), 67, 'check_password', ('decode', 'len', 'False', 'all', 'zip', 'ord'), 4, 6, ('s', 'good', 'cs', 'cg'))
|
|
|
|
for n, ov in zip(cnames, cvalues):
|
|
v = getattr(check_password.__code__, n)
|
|
if v == ov:
|
|
sys.stderr.write('\033[1;32m')
|
|
else:
|
|
sys.stderr.write('\033[1;31m')
|
|
sys.stderr.flush()
|
|
sys.stdout.write(str(n) + " " + str(v) + "\n")
|
|
sys.stdout.flush()
|
|
|
|
sys.stderr.write('\033[0m')
|
|
sys.stderr.flush()
|
|
|
|
dis.dis(check_password)
|