OC-PsychOS2/service/minitel.lua

274 lines
6.4 KiB
Lua

--[[
packet format:
packetID: random string to differentiate
packetType:
- 0: unreliable
- 1: reliable, requires ack
- 2: ack packet
destination: end destination hostname
sender: original sender of packet
data: the actual packet data, duh.
]]--
local listeners = {}
local timers = {}
local cfg = {}
local event = require "event"
local component = require "component"
local computer = require "computer"
local serial = require "serialization"
local hostname = computer.address():sub(1,8)
local modems = {}
local pid = nil
cfg.debug = false
cfg.port = 4096
cfg.retry = 10
cfg.retrycount = 3
cfg.route = true
--[[
LKR format:
address {
local hardware address
remote hardware address
time last received
}
]]--
cfg.sroutes = {}
local rcache = setmetatable({},{__index=cfg.sroutes})
cfg.rctime = 15
--[[
packet queue format:
{
packetID,
packetType
destination,
data,
timestamp,
attempts
}
]]--
local pqueue = {}
-- packet cache: [packet ID]=uptime
local pcache = {}
cfg.pctime = 30
local function dprint(...)
if cfg.debug then
print(...)
end
end
local function saveconfig()
local f = io.open("/boot/cfg/minitel.cfg","wb")
if f then
f:write(serial.serialize(cfg))
f:close()
end
end
local function loadconfig()
local f = io.open("/boot/cfg/minitel.cfg","rb")
if f then
local newcfg = serial.unserialize(f:read("*a"))
f:close()
for k,v in pairs(newcfg) do
cfg[k] = v
end
else
saveconfig()
end
end
function start()
loadconfig()
hostname = os.getenv("HOSTNAME") or computer.address():sub(1,8)
print("Hostname: "..hostname)
if pid then return false end
modems={}
for a,t in component.list("modem") do
modems[#modems+1] = component.proxy(a)
end
for k,v in ipairs(modems) do
v.open(cfg.port)
print("Opened port "..cfg.port.." on "..v.address)
end
for a,t in component.list("tunnel") do
modems[#modems+1] = component.proxy(a)
end
local function genPacketID()
local npID = ""
for i = 1, 16 do
npID = npID .. string.char(math.random(32,126))
end
return npID
end
local function sendPacket(packetID,packetType,dest,sender,vPort,data,repeatingFrom)
if rcache[dest] then
dprint("Cached", rcache[dest][1],"send",rcache[dest][2],cfg.port,packetID,packetType,dest,sender,vPort,data)
if component.type(rcache[dest][1]) == "modem" then
component.invoke(rcache[dest][1],"send",rcache[dest][2],cfg.port,packetID,packetType,dest,sender,vPort,data)
elseif component.type(rcache[dest][1]) == "tunnel" then
component.invoke(rcache[dest][1],"send",packetID,packetType,dest,sender,vPort,data)
end
else
dprint("Not cached", cfg.port,packetID,packetType,dest,sender,vPort,data)
for k,v in pairs(modems) do
-- do not send message back to the wired or linked modem it came from
-- the check for tunnels is for short circuiting `v.isWireless()`, which does not exist for tunnels
if v.address ~= repeatingFrom or (v.type ~= "tunnel" and v.isWireless()) then
if v.type == "modem" then
v.broadcast(cfg.port,packetID,packetType,dest,sender,vPort,data)
v.send(packetID,packetType,dest,sender,vPort,data)
end
end
end
end
end
local function pruneCache()
for k,v in pairs(rcache) do
dprint(k,v[3],computer.uptime())
if v[3] < computer.uptime() then
rcache[k] = nil
dprint("pruned "..k.." from routing cache")
end
end
for k,v in pairs(pcache) do
if v < computer.uptime() then
pcache[k] = nil
dprint("pruned "..k.." from packet cache")
end
end
end
local function checkPCache(packetID)
dprint(packetID)
for k,v in pairs(pcache) do
dprint(k)
if k == packetID then return true end
end
return false
end
local function processPacket(_,localModem,from,pport,_,packetID,packetType,dest,sender,vPort,data)
pruneCache()
if pport == cfg.port or pport == 0 then -- for linked cards
dprint(cfg.port,vPort,packetType,dest)
if checkPCache(packetID) then return end
if dest == hostname then
if packetType == 1 then
sendPacket(genPacketID(),2,sender,hostname,vPort,packetID)
end
if packetType == 2 then
dprint("Dropping "..data.." from queue")
pqueue[data] = nil
computer.pushSignal("net_ack",data)
end
if packetType ~= 2 then
computer.pushSignal("net_msg",sender,vPort,data)
end
elseif dest:sub(1,1) == "~" then -- broadcasts start with ~
computer.pushSignal("net_broadcast",sender,vPort,data)
elseif cfg.route then -- repeat packets if route is enabled
sendPacket(packetID,packetType,dest,sender,vPort,data,localModem)
end
if not rcache[sender] then -- add the sender to the rcache
dprint("rcache: "..sender..":", localModem,from,computer.uptime())
rcache[sender] = {localModem,from,computer.uptime()+cfg.rctime}
end
if not pcache[packetID] then -- add the packet ID to the pcache
pcache[packetID] = computer.uptime()+cfg.pctime
end
end
end
local function queuePacket(_,ptype,to,vPort,data,npID)
npID = npID or genPacketID()
if to == hostname or to == "localhost" then
computer.pushSignal("net_msg",to,vPort,data)
computer.pushSignal("net_ack",npID)
return
end
pqueue[npID] = {ptype,to,vPort,data,0,0}
dprint(npID,table.unpack(pqueue[npID]))
end
local function packetPusher()
for k,v in pairs(pqueue) do
if v[5] < computer.uptime() then
dprint(k,v[1],v[2],hostname,v[3],v[4])
sendPacket(k,v[1],v[2],hostname,v[3],v[4])
if v[1] ~= 1 or v[6] == cfg.retrycount then
pqueue[k] = nil
else
pqueue[k][5]=computer.uptime()+cfg.retry
pqueue[k][6]=pqueue[k][6]+1
end
end
end
end
listeners["modem_message"]=processPacket
listeners["net_send"]=queuePacket
listeners["net_ack"]=dprint
pid=os.spawn(function()
while true do
local ev = {coroutine.yield()}
packetPusher()
pruneCache()
if listeners[ev[1]] then
pcall(listeners[ev[1]],table.unpack(ev))
end
end
end,"minitel")
print("Started Minitel daemon: "..tostring(pid))
return pid
end
function stop()
if pid then
os.kill(pid)
pid = nil
return true
else
return false
end
end
function set(k,v)
if type(cfg[k]) == "string" then
cfg[k] = v
elseif type(cfg[k]) == "number" then
cfg[k] = tonumber(v)
elseif type(cfg[k]) == "boolean" then
if v:lower():sub(1,1) == "t" then
cfg[k] = true
else
cfg[k] = false
end
end
print("cfg."..k.." = "..tostring(cfg[k]))
saveconfig()
end
function set_route(to,laddr,raddr)
cfg.sroutes[to] = {laddr,raddr,0}
saveconfig()
end
function del_route(to)
cfg.sroutes[to] = nil
saveconfig()
end