| -rw-r--r-- | otfbot/plugins/ircClient/blowcrypt.py | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/otfbot/plugins/ircClient/blowcrypt.py b/otfbot/plugins/ircClient/blowcrypt.py new file mode 100644 index 0000000..447668a --- a/dev/null +++ b/otfbot/plugins/ircClient/blowcrypt.py @@ -0,0 +1,157 @@ +# This file is part of OtfBot. +# +# OtfBot is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# OtfBot is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with OtfBot; if not, write to the Free Software +# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +# +# (c) 2009 by Bjorn Edstrom +# (c) 2012 by spasswurst +# + +""" + Support for blowfish cryption on irc +""" + +from otfbot.lib import chatMod +from otfbot.lib.pluginSupport.decorators import callback_with_priority + +import struct +from Crypto.Cipher import Blowfish + +class Plugin(chatMod.chatMod): + B64 = "./0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" + + def __init__(self, bot): + self.bot = bot + self.config = bot.root.getServiceNamed("config") + + @callback_with_priority(100) + def topicUpdated(self, user, channel, newTopic): + key = self.getBlowkey(channel) + if not key: + return + topicdecrypted = self.blowfishDecrypt(newTopic, key) + if topicdecrypted: + result = self.bot.FURTHER_PROCESSING_THIS_ARGS, { "newTopic" : topicdecrypted} + return result + + @callback_with_priority(100) + def msg(self, user, channel, msg): + key = self.getBlowkey(channel) + if not key: + return + nick = user.getNick() + if nick.lower() != self.bot.nickname.lower(): # incoming msg? + msg = self.blowfishDecrypt(msg, key) + if msg: + char = msg[0] + if char == self.config.get("commandChar", "!", "main"): + tmp = msg[1:].split(" ", 1) + command = tmp[0] + if len(tmp) == 2: + options = tmp[1] + else: + options = "" + self.bot._synced_apirunner("command", {"user": user, "channel": channel, + "command": command, "options": options}) + return self.bot.NO_FURTHER_PROCESSING + result = self.bot.FURTHER_PROCESSING_THIS_ARGS, { "msg" : msg} + return result + + @callback_with_priority(100) + def sendLine(self, line): + s = line + if s[0] != ':' and s.find(' :') != -1: + s, trailing = s.split(' :', 1) + args = s.split() + args.append(trailing) + command = args.pop(0) + if command != "PRIVMSG": + return + + channel = args.pop(0) + msg = args.pop(0) + key = self.getBlowkey(channel) + if not key: + return + msg = self.blowfishCrypt(msg, key) + line = 'PRIVMSG %s :%s' % (channel, msg) + result = self.bot.FURTHER_PROCESSING_THIS_RESULT, { "line" : line} + return result + + def getBlowkey(self, channel): + if channel[0] in '#+!&': + channel = channel.lower() + key = self.config.get("blowkey", "", "main", self.bot.network, channel, set_default=False) + return key + + def blowcrypt_b64decode(self, s): + """A non-standard base64-decode.""" + res = '' + while s: + left, right = 0, 0 + for i, p in enumerate(s[0:6]): + right |= self.B64.index(p) << (i * 6) + for i, p in enumerate(s[6:12]): + left |= self.B64.index(p) << (i * 6) + res += struct.pack('>LL', left, right) + s = s[12:] + return res + + def blowcrypt_b64encode(self, s): + """A non-standard base64-encode.""" + res = '' + while s: + left, right = struct.unpack('>LL', s[:8]) + for i in xrange(6): + res += self.B64[right & 0x3f] + right >>= 6 + for i in xrange(6): + res += self.B64[left & 0x3f] + left >>= 6 + s = s[8:] + return res + + def padto(self, msg, length): + """Pads 'msg' with zeroes until it's length is divisible by 'length'. + If the length of msg is already a multiple of 'length', does nothing.""" + L = len(msg) + if L % length: + msg += '\x00' * (length - L % length) + assert len(msg) % length == 0 + return msg + + def blowfishDecrypt(self, message, key): + if not (message.startswith('+OK ') or message.startswith('mcps ')): + return + _, rest = message.split(' ', 1) + + try: + padded = self.padto(rest, 12) + raw = self.blowcrypt_b64decode(padded) + bf = Blowfish.new(key) + decrypted = bf.decrypt(raw) + decrypted = decrypted.strip('\x00') + return decrypted + except ValueError: + return + + def blowfishCrypt(self, message, key): + try: + padded = self.padto(message, 8) + bf = Blowfish.new(key) + crypted = bf.encrypt(padded) + crypted = '+OK ' + self.blowcrypt_b64encode(crypted) + return crypted + except ValueError: + return |