View difference between Paste ID: KixyLUWJ and 9KmQN99B

 local userDir = ".users"
 
 --SHA-256 API by GravityScore
 local MOD = 2^32
 local MODM = MOD-1
 
 local function memoize(f)
 	local mt = {}
 	local t = setmetatable({}, mt)
 	function mt:__index(k)
 		local v = f(k)
 		t[k] = v
 		return v
 	end
 	return t
 end
 
 local function make_bitop_uncached(t, m)
 	local function bitop(a, b)
 		local res,p = 0,1
 		while a ~= 0 and b ~= 0 do
 			local am, bm = a % m, b % m
 			res = res + t[am][bm] * p
 			a = (a - am) / m
 			b = (b - bm) / m
 			p = p*m
 		end
 		res = res + (a + b) * p
 		return res
 	end
 	return bitop
 end
 
 local function make_bitop(t)
 	local op1 = make_bitop_uncached(t,2^1)
 	local op2 = memoize(function(a) return memoize(function(b) return op1(a, b) end) end)
 	return make_bitop_uncached(op2, 2 ^ (t.n or 1))
 end
 
 local bxor1 = make_bitop({[0] = {[0] = 0,[1] = 1}, [1] = {[0] = 1, [1] = 0}, n = 4})
 
 local function bxor(a, b, c, ...)
 	local z = nil
 	if b then
 		a = a % MOD
 		b = b % MOD
 		z = bxor1(a, b)
 		if c then z = bxor(z, c, ...) end
 		return z
 	elseif a then return a % MOD
 	else return 0 end
 end
 
 local function band(a, b, c, ...)
 	local z
 	if b then
 		a = a % MOD
 		b = b % MOD
 		z = ((a + b) - bxor1(a,b)) / 2
 		if c then z = bit32_band(z, c, ...) end
 		return z
 	elseif a then return a % MOD
 	else return MODM end
 end
 
 local function bnot(x) return (-1 - x) % MOD end
 
 local function rshift1(a, disp)
 	if disp < 0 then return lshift(a,-disp) end
 	return math.floor(a % 2 ^ 32 / 2 ^ disp)
 end
 
 local function rshift(x, disp)
 	if disp > 31 or disp < -31 then return 0 end
 	return rshift1(x % MOD, disp)
 end
 
 local function lshift(a, disp)
 	if disp < 0 then return rshift(a,-disp) end
 	return (a * 2 ^ disp) % 2 ^ 32
 end
 
 local function rrotate(x, disp)
     x = x % MOD
     disp = disp % 32
     local low = band(x, 2 ^ disp - 1)
     return rshift(x, disp) + lshift(low, 32 - disp)
 end
 
 local k = {
 	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
 	0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
 	0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
 	0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
 	0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
 	0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
 	0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
 	0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
 	0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
 	0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
 	0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
 	0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
 	0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
 	0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
 	0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
 	0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
 }
 
 local function str2hexa(s)
 	return (string.gsub(s, ".", function(c) return string.format("%02x", string.byte(c)) end))
 end
 
 local function num2s(l, n)
 	local s = ""
 	for i = 1, n do
 		local rem = l % 256
 		s = string.char(rem) .. s
 		l = (l - rem) / 256
 	end
 	return s
 end
 
 local function s232num(s, i)
 	local n = 0
 	for i = i, i + 3 do n = n*256 + string.byte(s, i) end
 	return n
 end
 
 local function preproc(msg, len)
 	local extra = 64 - ((len + 9) % 64)
 	len = num2s(8 * len, 8)
 	msg = msg .. "\128" .. string.rep("\0", extra) .. len
 	assert(#msg % 64 == 0)
 	return msg
 end
 
 local function initH256(H)
 	H[1] = 0x6a09e667
 	H[2] = 0xbb67ae85
 	H[3] = 0x3c6ef372
 	H[4] = 0xa54ff53a
 	H[5] = 0x510e527f
 	H[6] = 0x9b05688c
 	H[7] = 0x1f83d9ab
 	H[8] = 0x5be0cd19
 	return H
 end
 
 local function digestblock(msg, i, H)
 	local w = {}
 	for j = 1, 16 do w[j] = s232num(msg, i + (j - 1)*4) end
 	for j = 17, 64 do
 		local v = w[j - 15]
 		local s0 = bxor(rrotate(v, 7), rrotate(v, 18), rshift(v, 3))
 		v = w[j - 2]
 		w[j] = w[j - 16] + s0 + w[j - 7] + bxor(rrotate(v, 17), rrotate(v, 19), rshift(v, 10))
 	end
 
 	local a, b, c, d, e, f, g, h = H[1], H[2], H[3], H[4], H[5], H[6], H[7], H[8]
 	for i = 1, 64 do
 		local s0 = bxor(rrotate(a, 2), rrotate(a, 13), rrotate(a, 22))
 		local maj = bxor(band(a, b), band(a, c), band(b, c))
 		local t2 = s0 + maj
 		local s1 = bxor(rrotate(e, 6), rrotate(e, 11), rrotate(e, 25))
 		local ch = bxor (band(e, f), band(bnot(e), g))
 		local t1 = h + s1 + ch + k[i] + w[i]
 		h, g, f, e, d, c, b, a = g, f, e, d + t1, c, b, a, t1 + t2
 	end
 
 	H[1] = band(H[1] + a)
 	H[2] = band(H[2] + b)
 	H[3] = band(H[3] + c)
 	H[4] = band(H[4] + d)
 	H[5] = band(H[5] + e)
 	H[6] = band(H[6] + f)
 	H[7] = band(H[7] + g)
 	H[8] = band(H[8] + h)
 end
 
 local function sha256(msg)
 	msg = preproc(msg, #msg)
 	local H = initH256({})
 	for i = 1, #msg, 64 do digestblock(msg, i, H) end
 	return str2hexa(num2s(H[1], 4) .. num2s(H[2], 4) .. num2s(H[3], 4) .. num2s(H[4], 4) ..
 		num2s(H[5], 4) .. num2s(H[6], 4) .. num2s(H[7], 4) .. num2s(H[8], 4))
 end
 
 --SHA-256 API end
 
 
 
 
 
 local tArg = {...}
 local progname = fs.getName(shell.getRunningProgram())
 
 local getTime = function()
 	return ((os.day()-1)*24)+(os.time()*1000)
 end
 
 addUser = function(name,password)
 	local file = fs.open(fs.combine(userDir,name),"w")
 	local out = {
 		password = sha256(password),
 		time = getTime(),
 		active = true,
 	}
 	file.write(textutils.serialize(out))
 	file.close()
 end
 
 if tArg[1] == "adduser" then
 	if not tArg[3] then
 		return print(progname.." useradd [name] [password]")
 	else
 		if fs.exists(fs.combine(userDir,tArg[2])) then
 			return print("Already exists...")
 		end
 		return adduser(tArg[2],tArg[3])
 	end
 elseif tArg[1] == "deluser" then
 	if not tArg[2] then
 		return print(progname.." deluser [user]")
 	else
 		if not fs.exists(fs.combine(userDir,tArg[2])) then
 			return print("No such user.")
 		end
 		return fs.delete(fs.combing(userDir,tArg[2]))
 	end
 end
 
 -- Find modems
 local tModems = {}
 for n,sModem in ipairs( peripheral.getNames() ) do
     if peripheral.getType( sModem ) == "modem" then
         table.insert( tModems, sModem )
     end
 end
 if #tModems == 0 then
     print( "No modems found." )
     return
 elseif #tModems == 1 then
     print( "1 modem found." )
 else
     print( #tModems .. " modems found." )
 end
 
 function open( nChannel )
     for n=1,#tModems do
         local sModem = tModems[n]
         peripheral.call( sModem, "open", nChannel )
     end
 end
 
 function close( nChannel )
     for n=1,#tModems do
         local sModem = tModems[n]
         peripheral.call( sModem, "close", nChannel )
     end
 end
 
 -- Open channels
 print( "0 messages repeated." )
 open( rednet.CHANNEL_REPEAT )
 
 -- Main loop (terminate to break)
 local ok, error = pcall( function()
     local tReceivedMessages = {}
     local tReceivedMessageTimeouts = {}
     local nTransmittedMessages = 0
 
     while true do
         local sEvent, sModem, nChannel, nReplyChannel, tMessage = os.pullEvent()
         if sEvent == "modem_message" then
             -- Got a modem message, rebroadcast it if it's a rednet thing
             if nChannel == rednet.CHANNEL_REPEAT then
                 if type( tMessage ) == "table" and tMessage.nMessageID and tMessage.nRecipient then
                     if not tReceivedMessages[ tMessage.nMessageID ] then
                         -- Ensure we only repeat a message once
                         tReceivedMessages[ tMessage.nMessageID ] = true
                         tReceivedMessageTimeouts[ os.startTimer( 30 ) ] = tMessage.nMessageID
 
                         -- Send on all other open modems, to the target and to other repeaters
                         for n=1,#tModems do
                             local sOtherModem = tModems[n]
                             peripheral.call( sOtherModem, "transmit", rednet.CHANNEL_REPEAT, nReplyChannel, tMessage )
                             peripheral.call( sOtherModem, "transmit", tMessage.nRecipient, nReplyChannel, tMessage )
                         end
 
                         -- Log the event
                         nTransmittedMessages = nTransmittedMessages + 1
                         local x,y = term.getCursorPos()
                         term.setCursorPos( 1, y - 1 )
                         term.clearLine()
                         if nTransmittedMessages == 1 then
                             print( nTransmittedMessages .. " message repeated." )
                         else
                             print( nTransmittedMessages .. " messages repeated." )
                         end
                     end
                 end
             end
 
         elseif sEvent == "timer" then
             -- Got a timer event, use it to clear the message history
             local nTimer = sModem
             local nMessageID = tReceivedMessageTimeouts[ nTimer ]
             if nMessageID then
                 tReceivedMessageTimeouts[ nTimer ] = nil
                 tReceivedMessages[ nMessageID ] = nil
             end
 
         end
     end
 end )
 if not ok then
     printError( error )
 end
 
 -- Close channels
 close( rednet.CHANNEL_REPEAT )