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 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314
|
local comm = require "comm"
local shortport = require "shortport"
local stdnse = require "stdnse"
local string = require "string"
local table = require "table"
description = [[
Checks an IRC server for channels that are commonly used by malicious botnets.
Control the list of channel names with the <code>irc-botnet-channels.channels</code>
script argument. The default list of channels is
* loic
* Agobot
* Slackbot
* Mytob
* Rbot
* SdBot
* poebot
* IRCBot
* VanBot
* MPack
* Storm
* GTbot
* Spybot
* Phatbot
* Wargbot
* RxBot
]]
author = {"David Fifield", "Ange Gutek"}
license = "Same as Nmap--See https://nmap.org/book/man-legal.html"
categories = {"discovery", "vuln", "safe"}
---
-- @usage
-- nmap -p 6667 --script=irc-botnet-channels <target>
-- @usage
-- nmap -p 6667 --script=irc-botnet-channels --script-args 'irc-botnet-channels.channels={chan1,chan2,chan3}' <target>
--
-- @args irc-botnet-channels.channels a list of channel names to check for.
--
-- @output
-- | irc-botnet-channels:
-- | #loic
-- |_ #RxBot
-- See RFC 2812 for protocol documentation.
-- Section 5.1 for protocol replies.
local RPL_TRYAGAIN = "263"
local RPL_LIST = "322"
local RPL_LISTEND = "323"
local DEFAULT_CHANNELS = {
"loic",
"Agobot",
"Slackbot",
"Mytob",
"Rbot",
"SdBot",
"poebot",
"IRCBot",
"VanBot",
"MPack",
"Storm",
"GTbot",
"Spybot",
"Phatbot",
"Wargbot",
"RxBot",
}
portrule = shortport.port_or_service({6666, 6667, 6697, 6679}, {"irc", "ircs"})
-- Parse an IRC message. Returns nil, errmsg in case of error. Otherwise returns
-- true, prefix, command, params. prefix may be nil. params is an array of
-- strings. The final param has the ':' stripped from the beginning.
--
-- The special return value true, nil indicates an empty message to be ignored.
--
-- See RFC 2812, section 2.3.1 for BNF of a message.
local function irc_parse_message(s)
local prefix, command, params
local _, p, t
s = string.gsub(s, "\r?\n$", "")
if string.match(s, "^ *$") then
return true, nil
end
p = 0
_, t, prefix = string.find(s, "^:([^ ]+) +", p + 1)
if t then
p = t
end
-- We do not check for any special format of the command name or
-- number.
_, p, command = string.find(s, "^([^ ]+)", p + 1)
if not p then
return nil, "Presumed message is missing a command."
end
params = {}
while p + 1 <= #s do
local param
_, p = string.find(s, "^ +", p + 1)
if not p then
return nil, "Missing a space before param."
end
-- We don't do any checks on the contents of params.
if #params == 14 then
params[#params + 1] = string.sub(s, p + 1)
break
elseif string.match(s, "^:", p + 1) then
params[#params + 1] = string.sub(s, p + 2)
break
else
_, p, param = string.find(s, "^([^ ]+)", p + 1)
if not p then
return nil, "Missing a param."
end
params[#params + 1] = param
end
end
return true, prefix, command, params
end
local function irc_compose_message(prefix, command, ...)
local parts, params
parts = {}
if prefix then
parts[#parts + 1] = prefix
end
if string.match(command, "^:") then
return nil, "Command may not begin with ':'."
end
parts[#parts + 1] = command
params = {...}
for i, param in ipairs(params) do
if not string.match(param, "^[^\0\r\n :][^\0\r\n ]*$") then
if i < #params then
return nil, "Bad format for param."
else
parts[#parts + 1] = ":" .. param
end
else
parts[#parts + 1] = param
end
end
return stdnse.strjoin(" ", parts) .. "\r\n"
end
local function random_nick()
return stdnse.generate_random_string(9, "abcdefghijklmnopqrstuvwxyz")
end
local function splitlines(s)
local lines = {}
local _, i, j
i = 1
while i <= #s do
_, j = string.find(s, "\r?\n", i)
lines[#lines + 1] = string.sub(s, i, j)
if not j then
break
end
i = j + 1
end
return lines
end
local function irc_connect(host, port, nick, user, pass)
local commands = {}
local irc = {}
local banner
-- Section 3.1.1.
if pass then
commands[#commands + 1] = irc_compose_message(nil, "PASS", pass)
end
nick = nick or random_nick()
commands[#commands + 1] = irc_compose_message(nil, "NICK", nick)
user = user or nick
commands[#commands + 1] = irc_compose_message(nil, "USER", user, "8", "*", user)
irc.sd, banner = comm.tryssl(host, port, table.concat(commands))
if not irc.sd then
return nil, "Unable to open connection."
end
irc.sd:set_timeout(60 * 1000)
-- Buffer these initial lines for irc_readline.
irc.linebuf = splitlines(banner)
irc.buf = stdnse.make_buffer(irc.sd, "\r?\n")
return irc
end
local function irc_disconnect(irc)
irc.sd:close()
end
local function irc_readline(irc)
local line
if next(irc.linebuf) then
line = table.remove(irc.linebuf, 1)
if string.match(line, "\r?\n$") then
return line
else
-- We had only half a line buffered.
return line .. irc.buf()
end
else
return irc.buf()
end
end
local function irc_read_message(irc)
local line, err
line, err = irc_readline(irc)
if not line then
return nil, err
end
return irc_parse_message(line)
end
local function irc_send_message(irc, prefix, command, ...)
local line
line = irc_compose_message(prefix, command, ...)
irc.sd:send(line)
end
-- Prefix channel names with '#' if necessary and concatenate into a
-- comma-separated list.
local function concat_channel_list(channels)
local mod = {}
for _, channel in ipairs(channels) do
if not string.match(channel, "^#") then
channel = "#" .. channel
end
mod[#mod + 1] = channel
end
return stdnse.strjoin(",", mod)
end
function action(host, port)
local irc
local search_channels
local channels
local errorparams
search_channels = stdnse.get_script_args(SCRIPT_NAME .. ".channels")
if not search_channels then
search_channels = DEFAULT_CHANNELS
elseif type(search_channels) == "string" then
search_channels = {search_channels}
end
irc = irc_connect(host, port)
irc_send_message(irc, "LIST", concat_channel_list(search_channels))
channels = {}
while true do
local status, prefix, code, params
status, prefix, code, params = irc_read_message(irc)
if not status then
-- Error message from irc_read_message.
errorparams = {prefix}
break
elseif code == "ERROR" then
errorparams = params
break
elseif code == RPL_TRYAGAIN then
errorparams = params
break
elseif code == RPL_LIST then
if #params >= 2 then
channels[#channels + 1] = params[2]
else
stdnse.debug1("Got short " .. RPL_LIST .. "response.")
end
elseif code == RPL_LISTEND then
break
end
end
irc_disconnect(irc)
if errorparams then
channels[#channels + 1] = "ERROR: " .. stdnse.strjoin(" ", errorparams)
end
return stdnse.format_output(true, channels)
end
|