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---
-- The AMQP library provides some basic functionality for retrieving information
-- about an AMQP server's properties.
--
-- Summary
-- -------
-- The library currently supports the AMQP 0-9 and 0-8 protocol specifications.
--
-- Overview
-- --------
-- The library contains the following classes:
--
-- o AMQP
-- - This class contains the core functions needed to communicate with AMQP
--
-- @args amqp.version Can be used to specify the client version to use (currently, 0-8, 0-9 or 0-9-1)
--
-- @copyright Same as Nmap--See https://nmap.org/book/man-legal.html
-- @author Sebastian Dragomir <velorien@gmail.com>
-- Version 0.1
-- Created 05/04/2011 - v0.1 - created by Sebastian Dragomir <velorien@gmail.com>
local match = require "match"
local nmap = require "nmap"
local stdnse = require "stdnse"
local string = require "string"
local table = require "table"
_ENV = stdnse.module("amqp", stdnse.seeall);
AMQP = {
-- protocol versions sent by the server
versions = {
[0x0800] = "0-8",
[0x0009] = "0-9"
},
-- version strings the client supports
client_version_strings = {
["0-8"] = "\x01\x01\x08\x00",
["0-9"] = "\x00\x00\x09\x00",
["0-9-1"] = "\x00\x00\x09\x01"
},
new = function(self, host, port)
local o = {}
setmetatable(o, self)
self.__index = self
o.host = host
o.port = port
o.amqpsocket = nmap.new_socket()
o.cli_version = self.client_version_strings[nmap.registry.args['amqp.version']] or self.client_version_strings["0-9-1"]
o.protover = nil
o.server_version = nil
o.server_product = nil
o.serer_properties = nil
return o
end,
--- Connects the AMQP socket
connect = function(self)
local data, status, msg
status, msg = self.amqpsocket:connect(self.host, self.port, "tcp")
return status, msg
end,
--- Disconnects the AMQP socket
disconnect = function(self)
self.amqpsocket:close()
end,
--- Decodes a table value in the server properties field.
--
-- @param tbl the decoded table
-- @param tsize number, the table size in bytes
-- @return status, true on success, false on failure
-- @return error string containing error message if status is false
-- @return decoded value
decodeTable = function(self, tbl, tsize)
local status, err, tmp, read, value
read = 0
while read < tsize do
local key, value
status, tmp = self.amqpsocket:receive_buf(match.numbytes(1), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading key length", nil
end
read = read + 1
tmp = string.unpack("B", tmp)
status, key = self.amqpsocket:receive_buf(match.numbytes(tmp), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading key", nil
end
read = read + tmp
status, tmp = self.amqpsocket:receive_buf(match.numbytes(1), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading value type for " .. key, nil
end
read = read + 1
if ( tmp == 'F' ) then -- table type
status, tmp = self.amqpsocket:receive_buf(match.numbytes(4), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading table size", nil
end
read = read + 4
value = {}
tmp = string.unpack(">I4", tmp)
status, err, value = self:decodeTable(value, tmp)
read = read + tmp
table.insert(tbl, key .. ": ")
table.insert(tbl, value)
elseif ( tmp == 'S' ) then -- string type
status, err, value, read = self:decodeString(key, read)
if ( key == "product" ) then
self.server_product = value
elseif ( key == "version" ) then
self.server_version = value
end
table.insert(tbl, key .. ": " .. value)
elseif ( tmp == 't' ) then -- boolean type
status, err, value, read = self:decodeBoolean(key, read)
table.insert(tbl, key .. ": " .. value)
end
if ( not(status) ) then
return status, err, nil
end
end
return true, nil, tbl
end,
--- Decodes a string value in the server properties field.
--
-- @param key string, the key being read
-- @param read number, number of bytes already read
-- @return status, true on success, false on failure
-- @return error string containing error message if status is false
-- @return decoded value
-- @return number of bytes read after decoding this value
decodeString = function(self, key, read)
local value, status, tmp
status, tmp = self.amqpsocket:receive_buf(match.numbytes(4), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading value size for " .. key, nil, 0
end
read = read + 4
tmp = string.unpack(">I4", tmp)
status, value = self.amqpsocket:receive_buf(match.numbytes(tmp), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading value for " .. key, nil, 0
end
read = read + tmp
return true, nil, value, read
end,
--- Decodes a boolean value in the server properties field.
--
-- @param key string, the key being read
-- @param read number, number of bytes already read
-- @return status, true on success, false on failure
-- @return error string containing error message if status is false
-- @return decoded value
-- @return number of bytes read after decoding this value
decodeBoolean = function(self, key, read)
local status, value
status, value = self.amqpsocket:receive_buf(match.numbytes(1), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading value for " .. key, nil, 0
end
value = string.unpack("B", value)
read = read + 1
return true, nil, value == 0x01 and "YES" or "NO", read
end,
--- Performs the AMQP handshake and determines
-- * The AMQP protocol version
-- * The server properties/capabilities
--
-- @return status, true on success, false on failure
-- @return error string containing error message if status is false
handshake = function(self)
local _, status, err, version, tmp, value, properties
status = self.amqpsocket:send( "AMQP" .. self.cli_version )
if ( not(status) ) then
return false, "ERROR: AMQP:handshake failed while sending client version"
end
status, tmp = self.amqpsocket:receive_buf(match.numbytes(11), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading frame header"
end
-- check if the server rejected our proposed version
if ( #tmp ~= 11 ) then
if ( #tmp == 8 and string.unpack(">I4", tmp) == 0x414D5150 ) then
local vi, vii, v1, v2, v3, v4, found
vi = string.unpack(">I4", tmp, 5)
found = false
-- check if we support the server's version
for _, v in pairs( self.client_version_strings ) do
vii = string.unpack(">I4", v)
if ( vii == vi ) then
version = v
found = true
break
end
end
-- try again with new version string
if ( found and version ~= self.cli_version ) then
self.cli_version = version
self:disconnect()
status, err = self:connect()
if ( not(status) ) then
return status, err
end
return self:handshake()
end
-- version unsupported
v1, v2, v3, v4 = string.unpack(">BBBB", tmp, 5)
return false, ("ERROR: AMQP:handshake unsupported version (%d.%d.%d.%d)"):format( v1, v2, v3, v4 )
else
return false, ("ERROR: AMQP:handshake server might not be AMQP, received: %s"):format( tmp )
end
end
-- parse frame header
local frametype, chnumber, framesize, method = string.unpack(">BI2I4I4", tmp)
stdnse.debug1("frametype: %d, chnumber: %d, framesize: %d, method: %d", frametype, chnumber, framesize, method)
if (frametype ~= 1) then
return false, ("ERROR: AQMP:handshake expected header (1) frame, but was %d"):format(frametype)
end
if (method ~= 0x000A000A) then
return false, ("ERROR: AQMP:handshake expected connection.start (0x000A000A) method, but was %x"):format(method)
end
-- parse protocol version
status, tmp = self.amqpsocket:receive_buf(match.numbytes(2), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading version"
end
version = string.unpack(">I2", tmp)
self.protover = AMQP.versions[version]
if ( not(self.protover) ) then
return false, ("ERROR: AMQP:handshake unsupported version (%x)"):format(version)
end
-- parse server properties
status, tmp = self.amqpsocket:receive_buf(match.numbytes(4), true)
if ( not(status) ) then
return status, "ERROR: AMQP:handshake connection closed unexpectedly while reading server properties size"
end
local tablesize = string.unpack(">I4", tmp)
properties = {}
status, err, properties = self:decodeTable(properties, tablesize)
if ( not(status) ) then
return status, err
end
status, err, value, tmp = self:decodeString("mechanisms", 0)
if ( not(status) ) then
return status, err
end
table.insert(properties, "mechanisms: " .. value)
status, err, value, tmp = self:decodeString("locales", 0)
if ( not(status) ) then
return status, err
end
table.insert(properties, "locales: " .. value)
self.server_properties = properties
return true
end,
--- Returns the protocol version reported by the server
--
-- @return string containing the version number
getProtocolVersion = function( self )
return self.protover
end,
--- Returns the product version reported by the server
--
-- @return string containing the version number
getServerVersion = function( self )
return self.server_version
end,
--- Returns the product name reported by the server
--
-- @return string containing the product name
getServerProduct = function( self )
return self.server_product
end,
--- Returns the properties reported by the server
--
-- @return table containing server properties
getServerProperties = function( self )
return self.server_properties
end,
}
return _ENV;