nodemcu-firmware/lua_modules/ftp/ftpserver.lua

516 lines
18 KiB
Lua

--[[SPLIT MODULE ftp]]
--[[ A simple ftp server
This is my implementation of a FTP server using Github user Neronix's
example as inspriration, but as a cleaner Lua implementation that is
suitable for use in LFS. The coding style adopted here is more similar to
best practice for normal (PC) module implementations, as using LFS enables
me to bias towards clarity of coding over brevity. It includes extra logic
to handle some of the edge case issues more robustly. It also uses a
standard forward reference coding pattern to allow the code to be laid out
in main routine, subroutine order.
The app will only call one FTP.open() or FTP.createServer() at any time,
with any multiple calls requected, so FTP is a singleton static object.
However there is nothing to stop multiple clients connecting to the FTP
listener at the same time, and indeed some FTP clients do use multiple
connections, so this server can accept and create multiple cxt objects.
Each cxt object can also have a single DATA connection.
Note that FTP also exposes a number of really private properties (which
could be stores in local / upvals) as FTP properties for debug purposes.
Note that this version has now been updated to allow the main methods to
be optionally loaded lazily, and SPILT comments allow the source to be
preprocessed for loading as either components in the "fast" Cmodule or as
LC files in SPIFFS.
]]
--luacheck: read globals fast file net node tmr uart wifi FAST_ftp SPIFFS_ftp
local FTP, FTPindex = {client = {}}, nil
if FAST_ftp then
function FTPindex(_, name) return fast.load('ftp-'..name) end
elseif SPIFFS_ftp then
function FTPindex(_, name) return loadfile('ftp-'..name..'.lc') end
end
if FTPindex then return setmetatable(FTP,{__index=FTPindex}) end
function FTP.open(...) --[[SPLIT HERE ftp-open]]
--------------------------- Set up the FTP object ----------------------------
-- FTP has three static methods: open, createServer and close
------------------------------------------------------------------------------
-- optional wrapper around createServer() which also starts the wifi session
-- Lua: FTP:open(user, pass, ssid, pwd[, dbgFlag])
local this, user, pass, ssid, pwd, dbgFlag = ...
if ssid then
wifi.setmode(wifi.STATION, false)
wifi.sta.config { ssid = ssid, pwd = pwd, save = false }
end
tmr.create():alarm(500, tmr.ALARM_AUTO, function(t) -- this: FTP, user, pass, dbgFlag
if (wifi.sta.status() == wifi.STA_GOTIP) then
t:unregister()
print("Welcome to NodeMCU world", node.heap(), wifi.sta.getip())
return this:createServer(user, pass, dbgFlag)
else
uart.write(0,".")
end
end)
end --[[SPLIT IGNORE]]
function FTP.createServer(...) --[[SPLIT HERE ftp-createServer]]
-- Lua: FTP:createServer(user, pass[, dbgFlag])
local this, user, pass, dbgFlag = ...
local cnt = 0
this.user, this.pass, dbgFlag = user, pass, (dbgFlag and true or false)
this.debug = (not dbgFlag) and type -- executing type(...) is in effect a NOOP
or function(fmt, ...) -- upval: cnt
if (...) then fmt = fmt:format(...) end
print(node.heap(),fmt)
cnt = cnt + 1
if cnt % 10 then tmr.wdclr() end
end
this.server = net.createServer(net.TCP, 180)
_G.FTP = this
this.debug("Server created: (userdata) %s", tostring(this.server))
this.server:listen(21, function(sock) -- upval: this
-- since a server can have multiple connections, each connection
-- has its own CXN object (table) to store connection-wide globals.
local CXN; CXN = {
validUser = false,
cmdSocket = sock,
debug = this.debug,
FTP = this,
send = function(rec, cb) -- upval: CXN
CXN.debug("Sending: %s", rec)
return CXN.cmdSocket:send(rec.."\r\n", cb)
end, --- CXN. send()
close = function(socket) -- upval: CXN
CXN.debug("Closing CXN.cmdSocket=%s", tostring(CXN.cmdSocket))
for _,s in ipairs{'cmdSocket', 'dataServer', 'dataSocket'} do
CXN.debug("closing CXN.%s=%s", s, tostring(CXN[s]))
if type(CXN[s])=='userdata' then
pcall(socket.close, CXN[s])
CXN[s]= nil
end
end
CXN.FTP.client[socket] = nil
end -- CXN.close()
}
local function validateUser(socket, data) -- upval: CXN
-- validate the logon and if then switch to processing commands
CXN.debug("Authorising: %s", data)
local cmd, arg = data:match('([A-Za-z]+) *([^\r\n]*)')
local msg = "530 Not logged in, authorization required"
cmd = cmd:upper()
if cmd == 'USER' then
CXN.validUser = (arg == CXN.FTP.user)
msg = CXN.validUser and
"331 OK. Password required" or
"530 user not found"
elseif CXN.validUser and cmd == 'PASS' then
if arg == CXN.FTP.pass then
CXN.cwd = '/'
socket:on("receive", function(soc, rec) -- upval: CXN
assert(soc==CXN.cmdSocket)
CXN.FTP.processCommand(CXN, rec)
end) -- logged on so switch to command mode
msg = "230 Login successful. Username & password correct; proceed."
else
msg = "530 Try again"
end
elseif cmd == 'AUTH' then
msg = "500 AUTH not understood"
end
return CXN.send(msg)
end
local port,ip = sock:getpeer() -- luacheck: no unused
--cxt.debug("Connection accepted: (userdata) %s client %s:%u", tostring(sock), ip, port)
sock:on("receive", validateUser)
sock:on("disconnection", CXN.close)
this.client[sock]=CXN
CXN.send("220 FTP server ready");
end) -- this.server:listen()
end --[[SPLIT IGNORE]]
function FTP.close(...) --[[SPLIT HERE ftp-close]]
-- Lua: FTP:close()
local this = ...
-- this.client is a table of soc = cnx. The first (and usually only connection) is cleared
-- immediately and next() used to do a post chain so we only close one client per task
local function rollupClients(skt,cxt) -- upval: this, rollupClients
if skt then
this.debug("Client close: %s", tostring(skt))
cxt.close(skt)
this.client[skt] = nil
node.task.post(function() return rollupClients(next(this.client, skt)) end) -- upval: rollupClients, this, skt
else -- we have emptied the open socket table, so can now shut the server
this.debug("Server close: %s", tostring(this. server))
this.server:close()
this.server:__gc()
_G.FTP = nil
end
end
rollupClients(next(this.client))
package.loaded.ftpserver = nil
end --[[SPLIT IGNORE]]
function FTP.processCommand(...) --[[SPLIT HERE ftp-processCommand]]
----------------------------- Process Command --------------------------------
-- This splits the valid commands into one of three categories:
-- * bare commands (which take no arg)
-- * simple commands (which take) a single arg; and
-- * data commands which initiate data transfer to or from the client and
-- hence need to use CBs.
--
-- Find strings are used do this lookup and minimise long if chains.
------------------------------------------------------------------------------
local cxt, data = ...
cxt.debug("Command: %s", data)
data = data:gsub('[\r\n]+$', '') -- chomp trailing CRLF
local cmd, arg = data:match('([a-zA-Z]+) *(.*)')
cmd = cmd:upper()
local _cmd_ = '_'..cmd..'_'
if ('_CDUP_NOOP_PASV_PWD_QUIT_SYST_'):find(_cmd_) then
cxt.FTP.processBareCmds(cxt, cmd)
elseif ('_CWD_DELE_MODE_PORT_RNFR_RNTO_SIZE_TYPE_'):find(_cmd_) then
cxt.FTP.processSimpleCmds(cxt, cmd, arg)
elseif ('_LIST_NLST_RETR_STOR_'):find(_cmd_) then
cxt.FTP.processDataCmds(cxt, cmd, arg)
else
cxt.send("500 Unknown error")
end
end --[[SPLIT IGNORE]]
function FTP.processBareCmds(...) --[[SPLIT HERE ftp-processBareCmds]]
-------------------------- Process Bare Commands -----------------------------
local cxt, cmd = ...
local send = cxt.send
if cmd == 'CDUP' then
return send("250 OK. Current directory is "..cxt.cwd)
elseif cmd == 'NOOP' then
return send("200 OK")
elseif cmd == 'PASV' then
-- This FTP implementation ONLY supports PASV mode, and the passive port
-- listener is opened on receipt of the PASV command. If any data xfer
-- commands return an error if the PASV command hasn't been received.
-- Note the listener service is closed on receipt of the next PASV or
-- quit.
local ip, port, pphi, pplo, i1, i2, i3, i4, _
_,ip = cxt.cmdSocket:getaddr()
port = 2121
pplo = port % 256
pphi = (port-pplo)/256
i1,i2,i3,i4 = ip:match("(%d+).(%d+).(%d+).(%d+)")
cxt.FTP.dataServer(cxt, port)
return send(
('227 Entering Passive Mode(%d,%d,%d,%d,%d,%d)'):format(
i1,i2,i3,i4,pphi,pplo))
elseif cmd == 'PWD' then
return send('257 "/" is the current directory')
elseif cmd == 'QUIT' then
send("221 Goodbye", function() cxt.close(cxt.cmdSocket) end) -- upval: cxt
return
elseif cmd == 'SYST' then
-- return send("215 UNKNOWN")
return send("215 UNIX Type: L8") -- must be Unix so ls is parsed correctly
else
error('Oops. Missed '..cmd)
end
end --[[SPLIT IGNORE]]
function FTP.processSimpleCmds(...) --[[SPLIT HERE ftp-processSimpleCmds]]
------------------------- Process Simple Commands ----------------------------
local cxt, cmd, arg = ...
local send = cxt.send
if cmd == 'MODE' then
return send(arg == "S" and "200 S OK" or
"504 Only S(tream) is suported")
elseif cmd == 'PORT' then
cxt.FTP.dataServer(cxt,nil) -- clear down any PASV setting
return send("502 Active mode not supported. PORT not implemented")
elseif cmd == 'TYPE' then
if arg == "A" then
cxt.xferType = 0
return send("200 TYPE is now ASII")
elseif arg == "I" then
cxt.xferType = 1
return send("200 TYPE is now 8-bit binary")
else
return send("504 Unknown TYPE")
end
end
-- The remaining commands take a filename as an arg. Strip off leading / and ./
arg = arg:gsub('^%.?/',''):gsub('^%.?/','')
cxt.debug("Filename is %s",arg)
if cmd == 'CWD' then
if arg:match('^[%./]*$') then
return send("250 CWD command successful")
end
return send("550 "..arg..": No such file or directory")
elseif cmd == 'DELE' then
if file.exists(arg) then
file.remove(arg)
if not file.exists(arg) then return send("250 Deleted "..arg) end
end
return send("550 Requested action not taken")
elseif cmd == 'RNFR' then
cxt.from = arg
send("350 RNFR accepted")
return
elseif cmd == 'RNTO' then
local status = cxt.from and file.rename(cxt.from, arg)
cxt.debug("rename('%s','%s')=%s", tostring(cxt.from), tostring(arg), tostring(status))
cxt.from = nil
return send(status and "250 File renamed" or
"550 Requested action not taken")
elseif cmd == "SIZE" then
local st = file.stat(arg)
return send(st and ("213 "..st.size) or
"550 Could not get file size.")
else
error('Oops. Missed '..cmd)
end
end --[[SPLIT IGNORE]]
function FTP.processDataCmds(...) --[[SPLIT HERE ftp-processDataCmds]]
-------------------------- Process Data Commands -----------------------------
local cxt, cmd, arg = ...
local send, FTP = cxt.send, cxt.FTP -- luacheck: ignore FTP
-- The data commands are only accepted if a PORT command is in scope
if FTP.dataServer == nil and cxt.dataSocket == nil then
return send("502 Active mode not supported. "..cmd.." not implemented")
end
cxt.getData, cxt.setData = nil, nil
arg = arg:gsub('^%.?/',''):gsub('^%.?/','')
if cmd == "LIST" or cmd == "NLST" then
-- There are
local fileSize, nameList, pattern = file.list(), {}, '.'
arg = arg:gsub('^-[a-z]* *', '') -- ignore any Unix style command parameters
arg = arg:gsub('^/','') -- ignore any leading /
if #arg > 0 and arg ~= '.' then -- replace "*" by [^/%.]* that is any string not including / or .
pattern = arg:gsub('*','[^/%%.]*')
end
for k, _ in pairs(fileSize) do
if k:match(pattern) then
nameList[#nameList+1] = k
else
fileSize[k] = nil
end
end
table.sort(nameList)
function cxt.getData(c) -- upval: cmd, fileSize, nameList
local list, user = {}, c.FTP.user
for i = 1,10 do -- luacheck: no unused
if #nameList == 0 then break end
local f = table.remove(nameList, 1)
list[#list+1] = (cmd == "LIST") and
("-rw-r--r-- 1 %s %s %6u Jan 1 00:00 %s\r\n"):format(user, user, fileSize[f], f) or
(f.."\r\n")
end
return table.concat(list)
end
elseif cmd == "RETR" then
local f = file.open(arg, "r")
if f then -- define a getter to read the file
function cxt.getData(c) -- luacheck: ignore c -- upval: f
local buf = f:read(1024)
if not buf then f:close(); f = nil; end
return buf
end -- cxt.getData()
end
elseif cmd == "STOR" then
local f = file.open(arg, "w")
if f then -- define a setter to write the file
function cxt.setData(c, rec) -- luacheck: ignore c -- upval: f (, arg)
cxt.debug("writing %u bytes to %s", #rec, arg)
return f:write(rec)
end -- cxt.saveData(rec)
function cxt.fileClose(c) -- luacheck: ignore c -- upval: f (,arg)
cxt.debug("closing %s", arg)
f:close(); f = nil
end -- cxt.close()
end
end
send((cxt.getData or cxt.setData) and "150 Accepted data connection" or
"451 Can't open/create "..arg)
if cxt.getData and cxt.dataSocket then
cxt.debug ("poking sender to initiate first xfer")
node.task.post(function() cxt.sender(cxt.dataSocket) end) -- upval: cxt
end
end --[[SPLIT IGNORE]]
function FTP.dataServer(...) --[[SPLIT HERE ftp-dataServer]]
----------------------------- Data Port Routines -----------------------------
-- These are used to manage the data transfer over the data port. This is
-- set up lazily either by a PASV or by the first LIST NLST RETR or STOR
-- command that uses it. These also provide a sendData / receiveData cb to
-- handle the actual xfer. Also note that the sending process can be primed in
--
---------------- Open a new data server and port ---------------------------
local cxt, n = ...
local dataSvr = cxt.dataServer
if dataSvr then pcall(dataSvr.close, dataSrv) end -- luacheck: ignore -- close any existing listener
if n then
-- Open a new listener if needed. Note that this is only used to establish
-- a single connection, so ftpDataOpen closes the server socket
dataSvr = net.createServer(net.TCP, 300)
cxt.dataServer = dataSvr
dataSvr:listen(n, function(sock) -- upval: cxt
cxt.FTP.ftpDataOpen(cxt,sock)
end)
cxt.debug("Listening on Data port %u, server %s",n, tostring(cxt.dataServer))
else
cxt.dataServer = nil
cxt.debug("Stopped listening on Data port",n)
end
end --[[SPLIT IGNORE]]
function FTP.ftpDataOpen(...) --[[SPLIT HERE ftp-ftpDataOpen]]
----------------------- Connection on FTP data port ------------------------
local cxt, dataSocket = ...
local sport,sip = dataSocket:getaddr()
local cport,cip = dataSocket:getpeer()
cxt.debug("Opened data socket %s from %s:%u to %s:%u", tostring(dataSocket),sip,sport,cip,cport )
cxt.dataSocket = dataSocket
cxt.dataServer:close()
cxt.dataServer = nil
function cxt.cleardown(cxt, skt, cdtype) --luacheck: ignore cxt -- shadowing
-- luacheck: ignore cdtype which
cdtype = cdtype==1 and "disconnection" or "reconnection"
local which = cxt.setData and "setData" or (cxt.getData and cxt.getData or "neither")
cxt.debug("Cleardown entered from %s with %s", cdtype, which)
if cxt.setData then
cxt:fileClose()
cxt.setData = nil
cxt.send("226 Transfer complete.")
else
cxt.getData, cxt.sender = nil, nil
end
cxt.debug("Clearing down data socket %s", tostring(skt))
node.task.post(function() -- upval: cxt, skt
pcall(skt.close, skt); skt=nil
cxt.dataSocket = nil
end)
end
local on_hold = false
dataSocket:on("receive", function(skt, rec) -- upval: cxt, on_hold
local rectype = cxt.setData and "setData" or (cxt.getData and cxt.getData or "neither")
cxt.debug("Received %u data bytes with %s", #rec, rectype)
if not cxt.setData then return end
if not on_hold then
-- Cludge to stop the client flooding the ESP SPIFFS on an upload of a
-- large file. As soon as a record arrives assert a flow control hold.
-- This can take up to 5 packets to come into effect at which point the
-- low priority unhold task is executed releasing the flow again.
cxt.debug("Issuing hold on data socket %s", tostring(skt))
skt:hold(); on_hold = true
node.task.post(node.task.LOW_PRIORITY,
function() -- upval: skt, on_hold
cxt.debug("Issuing unhold on data socket %s", tostring(skt))
pcall(skt.unhold, skt); on_hold = false
end)
end
if not cxt:setData(rec) then
cxt.debug("Error writing to SPIFFS")
cxt:fileClose()
cxt.setData = nil
cxt.send("552 Upload aborted. Exceeded storage allocation")
end
end)
function cxt.sender(skt) -- upval: cxt
cxt.debug ("entering sender")
if not cxt.getData then return end
skt = skt or cxt.dataSocket
local rec = cxt:getData()
if rec and #rec > 0 then
cxt.debug("Sending %u data bytes", #rec)
skt:send(rec)
else
cxt.debug("Send of data completed")
skt:close()
cxt.send("226 Transfer complete.")
cxt.getData, cxt.dataSocket = nil, nil
end
end
dataSocket:on("sent", cxt.sender)
dataSocket:on("disconnection", function(skt) return cxt:cleardown(skt,1) end) -- upval: cxt
dataSocket:on("reconnection", function(skt) return cxt:cleardown(skt,2) end) -- upval: cxt
-- if we are sending to client then kick off the first send
if cxt.getData then cxt.sender(cxt.dataSocket) end
end --[[SPLIT HERE]]
return FTP --[[SPLIT IGNORE]]