WeeChat scripts
Script: weefish.rb
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##
# weefish.rb
#
# Copyright (c) 2010 by Tobias Petersen <tp@unreal.dk>
#
# This program 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 3 of the License, or
# (at your option) any later version.
#
# This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
#
# FiSH encryption / decryption for Weechat
# based on blowfish, it is compatible with other
# FiSH scripts created for mIRC, irssi and XChat
#
# Thanks to someone without a name, for creating the FiSH script in ruby
# No DH1080 key exchange, only manual key, sorry!
#
# Usage:
# Set key for a given nick/channel, or the active nick/channel:
# /setkey [nick/channel] <secure key>
# Delete key for a given nick/channel, or the active nick/channel:
# /delkey [nick/channel] <secure key>
#
# History:
# 2012-02-08 bazerka <bazerka@irssi.org>
# version 0.4: fix in_privmsg to work with user targeted privmsg.
# bypass decrypting in_privmsg when no key is found.
# 2011-03-08 tp <tp@unreal.dk>
# version 0.3: fixed crypt/blowfish bug for ruby >= 1.9
# 2010-09-06, tp <tp@unreal.dk>
# version 0.2: fixed some message printing
# 2010-09-05, tp <tp@unreal.dk>
# version 0.1: initial release
require "crypt/blowfish"
def message buffer, message
Weechat.print buffer, "#{Weechat.prefix('error')}#{Weechat.color('bold')}weefish:#{Weechat.color('-bold')} #{message}"
end
def weechat_init
Weechat.register "weefish", "Tobias Petersen", "0.4", "GPL3", "FiSH encryption/decryption", "", ""
Weechat.hook_modifier "irc_in_privmsg", "in_privmsg", ""
Weechat.hook_modifier "irc_out_privmsg", "out_privmsg", ""
Weechat.hook_command "setkey", "Set the encryption key for the active nick/channel", "[nick/channel] <secure key>", "", "", "setkey", ""
Weechat.hook_command "delkey", "Delete the encryption key for the active nick/channel", "[nick/channel] <secure key>", "", "", "delkey", ""
return Weechat::WEECHAT_RC_OK
end
if RUBY_VERSION.to_f >= 1.9
module ::Crypt
class Blowfish
def setup_blowfish
@sBoxes = Array.new(4) { |i| INITIALSBOXES[i].clone }
@pArray = INITIALPARRAY.clone
keypos = 0
0.upto(17) { |i|
data = 0
4.times {
data = ((data << 8) | @key[keypos].ord) % ULONG
keypos = (keypos.next) % @key.length
}
@pArray[i] = (@pArray[i] ^ data) % ULONG
}
l = 0
r = 0
0.step(17, 2) { |i|
l, r = encrypt_pair(l, r)
@pArray[i] = l
@pArray[i+1] = r
}
0.upto(3) { |i|
0.step(255, 2) { |j|
l, r = encrypt_pair(l, r)
@sBoxes[i][j] = l
@sBoxes[i][j+1] = r
}
}
end
end
end
end
def setkey data, buffer, key
network, channel = Weechat.buffer_get_string(buffer, "name").split ".", 2
unless key.empty?
if key.scan(" ").length == 0
if network == "server"
message buffer, "No active nick/channel. Usage: /setkey <nick/channel> <secure key>"
else
message buffer, "Key for #{channel} (#{network}) successfully set!"
Weechat.config_set_plugin "key.#{network}.#{channel}", key
end
else
network = channel if network == "server"
channel, key = key.split " ", 2
message buffer, "Key for #{channel} (#{network}) successfully set!"
Weechat.config_set_plugin "key.#{network}.#{channel}", key
end
else
message buffer, "No parameters. Usage: /setkey [nick/channel] <secure key>"
end
end
def delkey data, buffer, string
network, channel = Weechat.buffer_get_string(buffer, "name").split ".", 2
if string.empty?
if network == "server"
message buffer, "No active nick/channel. Usage: /delkey <nick/channel>"
else
Weechat.config_unset_plugin "key.#{network}.#{channel}"
message buffer, "Key for #{channel} (#{network}) successfully deleted!"
end
else
network = channel if network == "server"
Weechat.config_unset_plugin "key.#{network}.#{string.split.first}"
message buffer, "Key for #{string.split.first} (#{network}) successfully deleted!"
end
end
def in_privmsg data, signal, server, args
if args =~ /^(:(.*?)!.*? PRIVMSG (.*?) :)(\+OK|mcps) (.*)$/
# If the PRIVMSG target ($3) is our current nick, we need the source nick ($2) to select the key
# config variable. Otherwise, assume it's a channel and use that to select the key instead.
selector = $3 == Weechat.info_get("irc_nick", server) ? $2 : $3
key = Weechat.config_string Weechat.config_get("plugins.var.ruby.weefish.key.#{server}.#{selector}")
# If we couldn't find a key, don't attempt to decrypt the message as Crypt::Blowfish will raise an
# invalid key length error on initialisation.
unless key.empty?
fish = IRC::FiSH.new key
if decrypted = fish.decrypt($5)
return $1+decrypted
end
end
end
return args
end
def out_privmsg data, signal, server, args
if args =~ /^(PRIVMSG (.*?) :)(.*)$/
key = Weechat.config_string Weechat.config_get("plugins.var.ruby.weefish.key.#{server}.#{$2}")
unless key.empty?
fish = IRC::FiSH.new key
return "#{$1}+OK #{fish.encrypt $3}"
else
return args
end
end
return args
end
module IRC
class BadInputError < StandardError; end
class MBase64
B64 = "./0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
def self.decode encoded
return nil if not encoded.length % 12 == 0
decoded = String.new
k = -1
while (k < encoded.length - 1) do
right = 0
left = 0
(0..5).each do |i|
k = k + 1
right |= B64.index(encoded[k]) << (i * 6)
end
(0..5).each do |i|
k = k + 1
left |= B64.index(encoded[k]) << (i * 6)
end
(0..3).each do |i|
decoded += ((left & (0xFF << ((3 - i) * 8))) >> ((3 - i) * 8)).chr
end
(0..3).each do |i|
decoded += ((right & (0xFF << ((3 - i) * 8))) >> ((3 - i) * 8)).chr
end
end
return decoded
end
def self.encode decoded
if not decoded.length % 8 == 0
raise IRC::BadInputError,
"can only encode strings which are a multiple of 8 characters."
end
encoded = String.new
k = -1
while (k < decoded.length - 1) do
k = k.next
left = (decoded[k].ord << 24)
k = k.next
left += (decoded[k].ord << 16)
k = k.next
left += (decoded[k].ord << 8)
k = k.next
left += decoded[k].ord
k = k.next
right = (decoded[k].ord << 24)
k = k.next
right += (decoded[k].ord << 16)
k = k.next
right += (decoded[k].ord << 8)
k = k.next
right += decoded[k].ord
(0..5).each do
encoded += B64[right & 0x3F].chr
right = right >> 6
end
(0..5).each do
encoded += B64[left & 0x3F].chr
left = left >> 6
end
end
return encoded
end
end
class FiSH
def initialize key
@blowfish = Crypt::Blowfish.new key
end
def encrypt text
text = pad(text, 8)
result = ""
num_block = text.length / 8
num_block.times do |n|
block = text[n*8..(n+1)*8-1]
enc = @blowfish.encrypt_block(block)
result += MBase64.encode(enc)
end
return result
end
def decrypt text
return nil if not text.length % 12 == 0
result = ""
num_block = (text.length / 12).to_i
num_block.times do |n|
block = MBase64.decode( text[n*12..(n+1)*12-1] )
result += @blowfish.decrypt_block(block)
end
return result.gsub /\0*$/, ""
end
private
def pad text, n=8
pad_num = n - (text.length % n)
if pad_num > 0 and pad_num != n
pad_num.times { text += 0.chr }
end
return text
end
end
end
