--- -- FTP functions. -- -- @copyright Same as Nmap--See http://nmap.org/book/man-legal.html local comm = require "comm" local stdnse = require "stdnse" local string = require "string" _ENV = stdnse.module("ftp", stdnse.seeall) local ERROR_MESSAGES = { ["EOF"] = "connection closed", ["TIMEOUT"] = "connection timeout", ["ERROR"] = "failed to receive data" } --- Connects to the FTP server based on the provided options. -- -- @param host The host table -- @param port The port table -- @param opts The connection option table, possible options: -- timeout: generic timeout value -- recv_before: receive data before returning -- @return socket The socket descriptor, or nil on errors -- @return response The response received on success and when -- the recv_before is set, or the error message on failures. connect = function(host, port, opts) local socket, _, _, ret = comm.tryssl(host, port, '', opts) if not socket then return socket, (ERROR_MESSAGES[ret] or 'unspecified error') end return socket, ret end --- -- Read an FTP reply and return the numeric code and the message. See RFC 959, -- section 4.2. -- @param buffer should have been created with -- stdnse.make_buffer(socket, "\r?\n"). -- @return numeric code or nil. -- @return text reply or error message. function read_reply(buffer) local readline local line, err local code, message local _, p, tmp line, err = buffer() if not line then return line, err end -- Single-line response? code, message = string.match(line, "^(%d%d%d) (.*)$") if code then return tonumber(code), message end -- Multi-line response? _, p, code, message = string.find(line, "^(%d%d%d)-(.*)$") if p then while true do line, err = buffer() if not line then return line, err end tmp = string.match(line, "^%d%d%d (.*)$") if tmp then message = message .. "\n" .. tmp break end message = message .. "\n" .. line end return tonumber(code), message end return nil, string.format("Unparseable response: %q", line) end return _ENV;