29 posts
Posted 28 February 2016 - 01:28 AM
I've been working on a pretty primitive OS to help get better at Lua. However everything was going great until I ran into an issue. Some variable is causing an error, and I've been all over the program, but nothing. Thanks.
--
-- Adaptation of the Secure Hashing Algorithm (SHA-244/256)
-- Found Here: http://lua-users.org/wiki/SecureHashAlgorithm
--
-- Using an adapted version of the bit library
-- Found Here: https://bitbucket.org/Boolsheet/bslf/src/1ee664885805/bit.lua
--
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
--Var
function drawMenu()
term.setBackgroundColor(colors.white)
term.clear()
term.setCursorPos(1,1)
term.setBackgroundColor(colors.gray)
term.setTextColor(colors.cyan)
term.write("b")
term.setTextColor(colors.white)
term.setCursorPos(2,1)
term.write("OS")
end
if not fs.exists("os/menu/password") then
local f = fs.open("os/menu/password", "w")
term.clear()
term.setCursorPos(1,1)
fs.open("os/menu/password", "r")
term.setCursorPos(1,1)
term.setBackgroundColor(colors.gray)
term.setTextColor(colors.black)
print("bOS Lock Configuration. ")
term.setCursorPos(1,17)
term.setBackgroundColor(colors.black)
term.setTextColor(colors.white)
print("Please enter password:")
term.setCursorPos(1,18)
term.setTextColor(colors.lightBlue)
local input = read("*")
local password = sha256(input)
print(password)
f.write(password)
f.close()
else
print("to be added")
end
