mirror of
https://github.com/20kdc/OC-KittenOS.git
synced 2024-11-14 14:38:05 +11:00
650 lines
18 KiB
Lua
650 lines
18 KiB
Lua
-- KittenOS N.E.O Kernel: "Tell Mettaton I said hi."
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-- This is released into the public domain.
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-- No warranty is provided, implied or otherwise.
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-- NOTE: local is considered unnecessary in kernel since 21 March
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-- In case of OpenComputers configuration abnormality
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readBufSize = 2048
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-- A function used for logging, usable by programs.
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emergencyFunction = function (...)
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computer.pushSignal("_kosneo_syslog", "kernel", ...)
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if ocemu and ocemu.log then
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pcall(ocemu.log, ...)
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end
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end
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-- Comment this out if you don't want programs to have
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-- access to ocemu's logger.
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ocemu = (component.list("ocemu", true)()) or (component.list("sandbox", true)())
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if ocemu then
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ocemu = component.proxy(ocemu)
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end
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-- It is a really bad idea to remove this.
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-- If the code inside this block even executes, then removing it is a security risk.
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if load(string.dump(function()end)) then
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emergencyFunction("detected bytecode access, preventing (only remove this block if you trust every app ever on your KittenOS NEO system)")
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local oldLoad = load
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load = function (c, n, m, ...)
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return oldLoad(c, n, "t", ...)
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end
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end
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primaryDisk = component.proxy(computer.getBootAddress())
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-- {{time, func, arg1...}...}
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timers = {}
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libraries = {}
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setmetatable(libraries, {__mode = "v"})
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-- proc.co = coroutine.create(appfunc)
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-- proc.pkg = "pkg"
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-- proc.access = {["perm"] = true, ...}
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-- proc.denied = {["perm"] = true, ...}
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-- proc.deathCBs = {function(), ...}
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-- very slightly adjusted total CPU time
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-- proc.cpuUsage
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processes = {}
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-- Maps registration-accesses to function(pkg, pid)
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accesses = {}
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lastPID = 0
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-- Kernel global "idle time" counter, useful for accurate performance data
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idleTime = 0
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-- This function is critical to wide text support.
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function unicode.safeTextFormat(s, ptr)
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local res = ""
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if not ptr then ptr = 1 end
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local aptr = 1
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for i = 1, unicode.len(s) do
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local ch = unicode.sub(s, i, i)
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local ex = unicode.charWidth(ch)
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if i < ptr then
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aptr = aptr + ex
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end
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for j = 2, ex do
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ch = ch .. " "
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end
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res = res .. ch
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end
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return res, aptr
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end
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-- The issue with the above function, of course, is that in practice the GPU is a weird mess.
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-- So this undoes the above transformation for feeding to gpu.set.
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-- (In practice if safeTextFormat supports RTL, and that's a big "if", then this will not undo that.
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-- The point is that this converts it into gpu.set format.)
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function unicode.undoSafeTextFormat(s)
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local res = ""
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local ignoreNext = false
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for i = 1, unicode.len(s) do
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if not ignoreNext then
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local ch = unicode.sub(s, i, i)
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if unicode.charWidth(ch) ~= 1 then
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if unicode.sub(s, i + 1, i + 1) ~= " " then
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ch = " "
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else
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ignoreNext = true
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end
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end
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res = res .. ch
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else
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ignoreNext = false
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end
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end
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return res
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end
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function loadfile(s, e)
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local h, er = primaryDisk.open(s)
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if h then
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local ch = ""
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local c = primaryDisk.read(h, readBufSize)
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while c do
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ch = ch .. c
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c = primaryDisk.read(h, readBufSize)
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end
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primaryDisk.close(h)
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return load(ch, "=" .. s, "t", e)
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end
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return nil, tostring(er)
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end
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uniqueNEOProtectionObject = {}
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wrapMetaCache = {}
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setmetatable(wrapMetaCache, {__mode = "v"})
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function wrapMeta(t)
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if type(t) == "table" then
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if wrapMetaCache[t] then
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return wrapMetaCache[t]
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end
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local t2 = {}
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wrapMetaCache[t] = t2
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setmetatable(t2, {
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__index = function (a, k) return wrapMeta(t[k]) end,
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__newindex = error,
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-- WTF
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__call = function (_, ...)
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return t(...)
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end,
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__pairs = function ()
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return function (x, key)
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local k, v = next(t, key)
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if k then return k, wrapMeta(v) end
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end, 9, nil
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end,
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__ipairs = function ()
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return function (x, key)
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key = key + 1
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if t[key] then
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return key, wrapMeta(t[key])
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end
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end, 9, 0
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end,
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__len = function ()
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return #t
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end,
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__metatable = uniqueNEOProtectionObject
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-- Don't protect this table - it'll make things worse
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})
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return t2
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else
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return t
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end
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end
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function ensureType(a, t)
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if type(a) ~= t then error("Invalid parameter, expected a " .. t) end
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if t == "table" then
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if getmetatable(a) then error("Invalid parameter, has metatable") end
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end
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end
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function ensurePathComponent(s)
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if not string.match(s, "^[a-zA-Z0-9_%-%+%,%.%#%~%@%'%;%[%]%(%)%&%%%$%! %=%{%}%^\x80-\xFF]+$") then error("chars disallowed: " .. s) end
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if s == "." then error("single dot disallowed") end
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if s == ".." then error("double dot disallowed") end
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end
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function ensurePath(s, r)
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string.gsub(s, "[^/]+", ensurePathComponent)
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if s:sub(1, r:len()) ~= r then error("base disallowed") end
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if s:match("//") then error("// disallowed") end
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end
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-- Use with extreme care.
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-- (A process killing itself will actually survive until the next yield... before any of the death events have run.)
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function termProc(pid, reason)
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if processes[pid] then
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-- Immediately prepare for GC, it's possible this is out of memory.
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-- If out of memory, then to reduce risk of memory leak by error, memory needs to be freed ASAP.
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-- Start by getting rid of all process data.
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local dcbs = processes[pid].deathCBs
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local pkg = processes[pid].pkg
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local usage = processes[pid].cpuUsage
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processes[pid] = nil
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-- This gets rid of a few more bits of data.
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for _, v in ipairs(dcbs) do
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v()
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end
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-- This finishes off that.
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dcbs = nil
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if reason then
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emergencyFunction("d1 " .. pkg .. "/" .. pid)
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emergencyFunction("d2 " .. reason)
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end
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-- And this is why it's important, because this generates timers.
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-- The important targets of these timers will delete even more data.
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distEvent(nil, "k.procdie", pkg, pid, reason, usage)
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end
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end
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function execEvent(k, ...)
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if processes[k] then
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local v = processes[k]
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local timerA = computer.uptime()
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local r, reason = coroutine.resume(v.co, ...)
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-- Mostly reliable accounting
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v.cpuUsage = v.cpuUsage + (computer.uptime() - timerA)
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reason = ((not r) and tostring(reason)) or nil
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local dead = (not not reason) or coroutine.status(v.co) == "dead"
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if dead then
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termProc(k, reason)
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return not not reason
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end
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end
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end
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function distEvent(pid, s, ...)
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local ev = {...}
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if pid then
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local v = processes[pid]
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if not v then
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return
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end
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if not (s:sub(1, 2) == "k." or v.access["s." .. s] or v.access["k.root"]) then
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return
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end
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-- Schedule the timer to carry the event.
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table.insert(timers, {0, execEvent, pid, s, table.unpack(ev)})
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else
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for k, v in pairs(processes) do
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distEvent(k, s, ...)
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end
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end
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end
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function lister(pfx)
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return function ()
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local n = primaryDisk.list(pfx)
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local n2 = {}
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for k, v in ipairs(n) do
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if v:sub(#v - 3) == ".lua" then
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table.insert(n2, v:sub(1, #v - 4))
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end
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end
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return n2
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end
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end
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function loadLibraryInner(library)
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ensureType(library, "string")
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library = "libs/" .. library .. ".lua"
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ensurePath(library, "libs/")
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if libraries[library] then return libraries[library] end
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emergencyFunction("loading " .. library)
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local l, r = loadfile(library, baseProcEnv())
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if l then
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local ok, al = pcall(l)
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if ok then
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al = wrapMeta(al)
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libraries[library] = al
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return al
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else
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return nil, al
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end
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end
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return nil, r
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end
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wrapMath = wrapMeta(math)
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wrapTable = wrapMeta(table)
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wrapString = wrapMeta(string)
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wrapUnicode = wrapMeta(unicode)
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wrapCoroutine = wrapMeta(coroutine)
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-- inject stuff into os
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os.totalMemory = computer.totalMemory
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os.freeMemory = computer.freeMemory
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os.energy = computer.energy
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os.maxEnergy = computer.maxEnergy
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os.uptime = computer.uptime
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os.address = computer.address
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wrapOs = wrapMeta(os)
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wrapDebug = wrapMeta(debug)
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wrapBit32 = wrapMeta(bit32)
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wrapUtf8 = wrapMeta(utf8)
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baseProcEnvCore = {
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_VERSION = _VERSION,
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math = wrapMath,
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table = wrapTable,
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string = wrapString,
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unicode = wrapUnicode,
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coroutine = wrapCoroutine,
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os = wrapOs,
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debug = wrapDebug,
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bit32 = wrapBit32,
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utf8 = wrapUtf8,
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require = loadLibraryInner,
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assert = assert, ipairs = ipairs,
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next = function (t, k)
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local mt = getmetatable(t)
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if mt == uniqueNEOProtectionObject then error("NEO-Protected Object") end
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return next(t, k)
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end,
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pairs = pairs, pcall = pcall,
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xpcall = xpcall, select = select,
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type = type, error = error,
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tonumber = tonumber, tostring = tostring,
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setmetatable = setmetatable, getmetatable = function (n)
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local mt = getmetatable(n)
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if rawequal(mt, uniqueNEOProtectionObject) then return "NEO-Protected Object" end
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return mt
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end,
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rawset = function (t, i, v)
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local mt = getmetatable(t)
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if rawequal(mt, uniqueNEOProtectionObject) then error("NEO-Protected Object") end
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return rawset(t, i, v)
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end, rawget = rawget, rawlen = rawlen, rawequal = rawequal,
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checkArg = checkArg
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}
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baseProcNeo = {
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emergency = emergencyFunction,
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readBufSize = readBufSize,
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wrapMeta = wrapMeta,
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listProcs = function ()
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local n = {}
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for k, v in pairs(processes) do
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table.insert(n, {k, v.pkg, v.cpuUsage})
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end
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return n
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end,
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listApps = lister("apps/"),
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listLibs = lister("libs/"),
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usAccessExists = function (accessName)
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ensureType(accessName, "string")
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return not not accesses[accessName]
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end,
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totalIdleTime = function () return idleTime end,
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ensurePath = ensurePath,
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ensurePathComponent = ensurePathComponent,
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ensureType = ensureType
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}
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baseProcEnvMT = {
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__index = baseProcEnvCore,
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__metatable = uniqueNEOProtectionObject
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}
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baseProcNeoMT = {
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__index = baseProcNeo,
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__metatable = uniqueNEOProtectionObject
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}
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function baseProcEnv()
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local pe = setmetatable({}, baseProcEnvMT)
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pe.load = function (a, b, c, d, ...)
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if rawequal(d, nil) then
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d = pe
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end
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return load(a, b, c, d, ...)
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end
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pe.neo = setmetatable({}, baseProcNeoMT)
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pe._G = pe
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return pe
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end
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-- These two are hooks for k.root level applications to change policy.
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-- Only a k.root application is allowed to do this for obvious reasons.
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function securityPolicy(pid, proc, perm, req)
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-- Important safety measure : only sys-* gets anything at first
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req(proc.pkg:sub(1, 4) == "sys-")
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end
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function runProgramPolicy(ipkg, pkg, pid, ...)
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-- VERY specific injunction here:
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-- non "sys-" apps NEVER start "sys-" apps
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-- This is part of the "default security policy" below:
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-- sys- has all access
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-- anything else has none
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if ipkg:sub(1, 4) == "sys-" then
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if pkg:sub(1, 4) ~= "sys-" then
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return nil, "non-sys app trying to start sys app"
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end
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end
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return true
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end
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function retrieveAccess(perm, pkg, pid)
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-- Return the access lib and the death callback.
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-- Access categories are sorted into:
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-- "c.<hw>": Component
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-- "s.<event>": Signal receiver (with responsibilities for Security Request watchers)
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-- "s.k.<...>": Kernel stuff
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-- "s.k.procnew" : New process (pkg, pid, ppkg, ppid)
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-- "s.k.procdie" : Process dead (pkg, pid, reason, usage)
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-- "s.k.registration" : Registration of service alert ("x." .. etc)
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-- "s.k.deregistration" : Registration of service alert ("x." .. etc)
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-- "s.k.securityresponse" : Response from security policy (accessId, accessObj)
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-- "s.h.<...>": Incoming HW messages
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-- "s.x.<endpoint>": This access is actually useless on it's own - it is given by x.<endpoint>
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-- "k.<x>": Kernel
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-- "k.root": _ENV (holy grail), and indirectly security request control (which is basically equivalent to this)
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-- "k.computer": computer
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-- "r.<endpoint>": Registration Of Service...
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-- "x.<endpoint>": Access Of Service (handled by r. & accesses table)
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if accesses[perm] then
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return accesses[perm](pkg, pid)
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end
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if perm == "k.root" then
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return _ENV
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end
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if perm == "k.computer" then
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return wrapMeta(computer)
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end
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if perm == "k.kill" then
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return function(npid)
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ensureType(npid, "number")
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termProc(npid, "Killed by " .. pkg .. "/" .. pid)
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end
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end
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if perm:sub(1, 2) == "s." then
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-- This is more of a "return success". Signal access is determined by the access/denied maps.
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return true
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end
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if perm:sub(1, 2) == "c." then
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-- Allows for simple "Control any of these connected to the system" APIs,
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-- for things the OS shouldn't be poking it's nose in.
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local primary = nil
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local temporary = nil
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local t = perm:sub(3)
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if t == "filesystem" then
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primary = wrapMeta(primaryDisk)
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temporary = wrapMeta(component.proxy(computer.tmpAddress()))
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end
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return {
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list = function ()
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local i = component.list(t, true)
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return function ()
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local ii = i()
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if not ii then return nil end
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return wrapMeta(component.proxy(ii))
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end
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end,
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primary = primary,
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temporary = temporary
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}
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end
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if perm:sub(1, 2) == "r." then
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local uid = "x" .. perm:sub(2)
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local sid = "s.x" .. perm:sub(2)
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if accesses[uid] then return nil end
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accesses[uid] = function (pkg, pid)
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return nil
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end
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return function (f)
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-- Registration function
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ensureType(f, "function")
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local accessObjectCache = {}
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accesses[uid] = function(pkg, pid)
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-- Basically, a per registration per process cache.
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-- This is a consistent yet flexible behavior.
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if accessObjectCache[pid] then
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return accessObjectCache[pid]
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end
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processes[pid].access[sid] = true
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local ok, a = pcall(f, pkg, pid, function (...)
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distEvent(pid, uid, ...)
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end)
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if ok then
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accessObjectCache[pid] = a
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return a, function ()
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accessObjectCache[pid] = nil
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end
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end
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-- returns nil and fails
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end
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-- Announce registration
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distEvent(nil, "k.registration", uid)
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end, function ()
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-- Registration becomes null (access is held but other processes cannot retrieve object)
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if accesses[uid] then
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distEvent(nil, "k.deregistration", uid)
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end
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accesses[uid] = nil
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end
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end
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end
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function start(pkg, ppkg, ppid, ...)
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local proc = {}
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local pid = lastPID
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emergencyFunction("starting:", pkg)
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lastPID = lastPID + 1
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local function startFromUser(ipkg, ...)
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ensureType(ipkg, "string")
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local ok, n = pcall(ensurePathComponent, ipkg .. ".lua")
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if not ok then return nil, n end
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local k, r = runProgramPolicy(ipkg, pkg, pid, ...)
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if k then
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return start(ipkg, pkg, pid, ...)
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else
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return k, r
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end
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end
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local function osExecuteCore(handler, ...)
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local pid, err = startFromUser(...)
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while pid do
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local sig = {coroutine.yield()}
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handler(table.unpack(sig))
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if sig[1] == "k.procdie" then
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if sig[3] == pid then
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return 0, sig[4]
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end
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end
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end
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return -1, err
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end
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local requestAccessAsync = function (perm)
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ensureType(perm, "string")
|
|
-- Safety-checked, prepare security event.
|
|
local req = function (res)
|
|
if processes[pid] then
|
|
local n = nil
|
|
local n2 = nil
|
|
if res then
|
|
proc.access[perm] = true
|
|
proc.denied[perm] = nil
|
|
n, n2 = retrieveAccess(perm, pkg, pid)
|
|
if n2 then
|
|
table.insert(processes[pid].deathCBs, n2)
|
|
end
|
|
else
|
|
proc.denied[perm] = true
|
|
end
|
|
distEvent(pid, "k.securityresponse", perm, n)
|
|
end
|
|
end
|
|
-- outer security policy:
|
|
if proc.access["k.root"] or proc.access[perm] or proc.denied[perm] then
|
|
-- Use cached result to prevent possible unintentional security service spam
|
|
req(proc.access["k.root"] or not proc.denied[perm])
|
|
return
|
|
end
|
|
-- Denied goes to on to prevent spam
|
|
proc.denied[perm] = true
|
|
securityPolicy(pid, proc, perm, req)
|
|
end
|
|
local env = baseProcEnv()
|
|
env.neo.pid = pid
|
|
env.neo.pkg = pkg
|
|
env.neo.executeAsync = startFromUser
|
|
env.neo.execute = function (...)
|
|
return osExecuteCore(function () end, ...)
|
|
end
|
|
env.neo.executeExt = osExecuteCore
|
|
env.neo.requestAccessAsync = requestAccessAsync
|
|
env.neo.requestAccess = function (perm, handler)
|
|
requestAccessAsync(perm)
|
|
handler = handler or function() end
|
|
while true do
|
|
local n = {coroutine.yield()}
|
|
handler(table.unpack(n))
|
|
if n[1] == "k.securityresponse" then
|
|
-- Security response - if it involves the permission, then take it
|
|
if n[2] == perm then return n[3] end
|
|
end
|
|
end
|
|
end
|
|
env.neo.requireAccess = function (perm, reason)
|
|
-- Allows for hooking
|
|
local res = env.neo.requestAccess(perm)
|
|
if not res then error(pkg .. " needed " .. perm .. " for " .. (reason or "some reason")) end
|
|
return res
|
|
end
|
|
env.neo.scheduleTimer = function (time)
|
|
ensureType(time, "number")
|
|
local tag = {}
|
|
table.insert(timers, {time, execEvent, pid, "k.timer", tag, time})
|
|
return tag
|
|
end
|
|
|
|
local appfunc, r = loadfile("apps/" .. pkg .. ".lua", env)
|
|
if not appfunc then
|
|
return nil, r
|
|
end
|
|
proc.co = coroutine.create(function (...) local r = {xpcall(appfunc, debug.traceback, ...)} if not r[1] then error(table.unpack(r, 2)) end return table.unpack(r, 2) end)
|
|
proc.pkg = pkg
|
|
proc.access = {}
|
|
proc.denied = {}
|
|
-- You are dead. Not big surprise.
|
|
proc.deathCBs = {function () pcall(function () env.neo.dead = true end) end}
|
|
proc.cpuUsage = 0
|
|
-- Note the target process doesn't get the procnew (the dist occurs before it's creation)
|
|
pcall(distEvent, nil, "k.procnew", pkg, pid, ppkg, ppid)
|
|
processes[pid] = proc
|
|
table.insert(timers, {0, execEvent, pid, ppkg, ppid, ...})
|
|
return pid
|
|
end
|
|
|
|
-- Kernel Scheduling Loop --
|
|
|
|
if not start("sys-init") then error("Could not start sys-init") end
|
|
|
|
while true do
|
|
local tmr = nil
|
|
for i = 1, 16 do
|
|
tmr = nil
|
|
local now = computer.uptime()
|
|
local didAnything = false -- for early exit
|
|
local k = 1
|
|
while timers[k] do
|
|
local v = timers[k]
|
|
if v[1] <= now then
|
|
table.remove(timers, k)
|
|
if v[2](table.unpack(v, 3)) then
|
|
didAnything = false -- to break
|
|
tmr = 0.05
|
|
break
|
|
end
|
|
didAnything = true
|
|
else
|
|
if not tmr then
|
|
tmr = v[1]
|
|
else
|
|
tmr = math.min(tmr, v[1])
|
|
end
|
|
k = k + 1
|
|
end
|
|
end
|
|
if not didAnything then break end
|
|
end
|
|
now = computer.uptime() -- the above probably took a while
|
|
local dist = tmr and math.max(0.05, tmr - now)
|
|
local signal = {computer.pullSignal(dist)}
|
|
idleTime = idleTime + (computer.uptime() - now)
|
|
if signal[1] then
|
|
distEvent(nil, "h." .. signal[1], select(2, table.unpack(signal)))
|
|
end
|
|
end
|