Created
September 20, 2014 17:44
-
-
Save yogeesh/4384408414e07da68821 to your computer and use it in GitHub Desktop.
CSAW 2014 crypto - 200 points
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| ''' | |
| crypto - 200 | |
| ''' | |
| import socket | |
| def getTranslatedMessage(message): | |
| key=-1 | |
| translated='' | |
| for symbol in message: | |
| if symbol.isalpha(): | |
| num = ord(symbol) | |
| num += key | |
| if symbol.isupper(): | |
| if num > ord('Z'): | |
| num -= 26 | |
| elif num < ord('A'): | |
| num += 26 | |
| elif symbol.islower(): | |
| if num > ord('z'): | |
| num -= 26 | |
| elif num < ord('a'): | |
| num += 26 | |
| translated += chr(num) | |
| else: | |
| translated += symbol | |
| return translated | |
| def decipher(msg): | |
| for i in range(0, 30): | |
| msg = getTranslatedMessage(msg) | |
| if 'the answer to this stage is' in msg: | |
| #print msg | |
| return msg | |
| def filter_recv(data): | |
| data = data.split('\n') | |
| #print data | |
| for x in data: | |
| print x | |
| if 'psifer text:' in x: | |
| msg = x.replace(r'psifer text: ', '') | |
| return msg | |
| ''' | |
| start here | |
| ''' | |
| s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) | |
| host = '54.209.5.48' | |
| port = 12345 | |
| s.connect((host, port)) | |
| s.recv(2048) | |
| data = s.recv(4096) | |
| msg = filter_recv(data) | |
| ans = decipher(msg) | |
| print ans | |
| ans = ans.replace(r'the answer to this stage is ', '') | |
| s.send(ans+'\n') | |
| data = s.recv(2048) | |
| print data |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment