Add some silly examples

Make maskS from x25519c.lua local

README.md

@@ -1,6 +1,12 @@
 # CCryptoLib
 An integrated collection of cryptographic primitives written in Lua using the ComputerCraft system API.
 
+## Installation
+A simple install script is provided, just run the following command: `wget run https://git.chrischro.me/ChrisChrome/ccryptolib/raw/branch/main/install.lua`
+
+## Initialization
+An `init.lua` is provided to allow easier access to all modules, use `crypto = require("ccryptolib")` in your script to use the module!
+
 ## Initializing the Random Number Generator
 All functions that take secret input may query the library's random generator,
 `ccryptolib.random`. CC doesn't have high-quality entropy sources, so instead of
@@ -11,7 +17,7 @@ hoping for the best like other libraries do, CCryptoLib shifts that burden into
 If you trust the tmpim Krist node, you can fetch a socket token and use it for
 initialization:
 ```lua
-local random = require "ccryptolib.random"
+local crypto = require("ccryptolib")
 
 -- Fetch a WebSocket token.
 local postHandle = assert(http.post("https://krist.dev/ws/start", ""))
@@ -19,7 +25,7 @@ local data = textutils.unserializeJSON(postHandle.readAll())
 postHandle.close()
 
 -- Initialize the generator using the given URL.
-random.init(data.url)
+crypto.random.init(data.url)
 
 -- Be polite and actually open the socket too.
 http.websocket(data.url).close()
@@ -29,6 +35,6 @@ http.websocket(data.url).close()
 As of v1.2.0, you can also initialize the generator using VM instruction timing noise.
 See the `random.initWithTiming` method for security risks of taking this approach.
 ```lua
-local random = require "ccryptolib.random"
+local crypto = require("ccryptolib")
-random.initWithTiming()
+crypto.random.initWithTiming()
 ```

ccryptolib/init.lua

@@ -0,0 +1,13 @@
+return {
+	random = require("ccryptolib.random");
+	aead = require("ccryptolib.aead");
+	blake3 = require("ccryptolib.blake3");
+	chacha20 = require("ccryptolib.chacha20");
+	ed25519 = require("ccryptolib.ed25519");
+	poly1305 = require("ccryptolib.poly1305");
+	sha256 = require("ccryptolib.sha256");
+	sha512 = require("ccryptolib.sha512");
+	util = require("ccryptolib.util");
+	x25519 = require("ccryptolib.x25519");
+	x25519c = require("ccryptolib.x25519c");
+}

ccryptolib/random.lua

@@ -9,7 +9,8 @@ local lassert = util.lassert
 local ctx = {
     "ccryptolib 2023-04-11T19:43Z random.lua initialization context",
     os.epoch("utc"),
-    os.epoch("ingame"),
+    os.day(),
+    os.time(),
     math.random(0, 2 ^ 24 - 1),
     math.random(0, 2 ^ 24 - 1),
     tostring({}),

ccryptolib/sha512.lua

@@ -0,0 +1,169 @@
+--- The SHA512 cryptographic hash function.
+
+local expect  = require "cc.expect".expect
+local packing = require "ccryptolib.internal.packing"
+
+local shl = bit32.lshift
+local shr = bit32.rshift
+local bxor = bit32.bxor
+local bnot = bit32.bnot
+local band = bit32.band
+local p1x16, fmt1x16 = packing.compilePack(">I16")
+local p16x4, fmt16x4 = packing.compilePack(">I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4")
+local u32x4, fmt32x4 = packing.compileUnpack(">I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4I4")
+
+local function carry64(a1, a0)
+    local r0 = a0 % 2 ^ 32
+    a1 = a1 + (a0 - r0) / 2 ^ 32
+    return a1 % 2 ^ 32, r0
+end
+
+local K = {
+    0x428a2f98, 0xd728ae22, 0x71374491, 0x23ef65cd, 0xb5c0fbcf, 0xec4d3b2f,
+    0xe9b5dba5, 0x8189dbbc, 0x3956c25b, 0xf348b538, 0x59f111f1, 0xb605d019,
+    0x923f82a4, 0xaf194f9b, 0xab1c5ed5, 0xda6d8118, 0xd807aa98, 0xa3030242,
+    0x12835b01, 0x45706fbe, 0x243185be, 0x4ee4b28c, 0x550c7dc3, 0xd5ffb4e2,
+    0x72be5d74, 0xf27b896f, 0x80deb1fe, 0x3b1696b1, 0x9bdc06a7, 0x25c71235,
+    0xc19bf174, 0xcf692694, 0xe49b69c1, 0x9ef14ad2, 0xefbe4786, 0x384f25e3,
+    0x0fc19dc6, 0x8b8cd5b5, 0x240ca1cc, 0x77ac9c65, 0x2de92c6f, 0x592b0275,
+    0x4a7484aa, 0x6ea6e483, 0x5cb0a9dc, 0xbd41fbd4, 0x76f988da, 0x831153b5,
+    0x983e5152, 0xee66dfab, 0xa831c66d, 0x2db43210, 0xb00327c8, 0x98fb213f,
+    0xbf597fc7, 0xbeef0ee4, 0xc6e00bf3, 0x3da88fc2, 0xd5a79147, 0x930aa725,
+    0x06ca6351, 0xe003826f, 0x14292967, 0x0a0e6e70, 0x27b70a85, 0x46d22ffc,
+    0x2e1b2138, 0x5c26c926, 0x4d2c6dfc, 0x5ac42aed, 0x53380d13, 0x9d95b3df,
+    0x650a7354, 0x8baf63de, 0x766a0abb, 0x3c77b2a8, 0x81c2c92e, 0x47edaee6,
+    0x92722c85, 0x1482353b, 0xa2bfe8a1, 0x4cf10364, 0xa81a664b, 0xbc423001,
+    0xc24b8b70, 0xd0f89791, 0xc76c51a3, 0x0654be30, 0xd192e819, 0xd6ef5218,
+    0xd6990624, 0x5565a910, 0xf40e3585, 0x5771202a, 0x106aa070, 0x32bbd1b8,
+    0x19a4c116, 0xb8d2d0c8, 0x1e376c08, 0x5141ab53, 0x2748774c, 0xdf8eeb99,
+    0x34b0bcb5, 0xe19b48a8, 0x391c0cb3, 0xc5c95a63, 0x4ed8aa4a, 0xe3418acb,
+    0x5b9cca4f, 0x7763e373, 0x682e6ff3, 0xd6b2b8a3, 0x748f82ee, 0x5defb2fc,
+    0x78a5636f, 0x43172f60, 0x84c87814, 0xa1f0ab72, 0x8cc70208, 0x1a6439ec,
+    0x90befffa, 0x23631e28, 0xa4506ceb, 0xde82bde9, 0xbef9a3f7, 0xb2c67915,
+    0xc67178f2, 0xe372532b, 0xca273ece, 0xea26619c, 0xd186b8c7, 0x21c0c207,
+    0xeada7dd6, 0xcde0eb1e, 0xf57d4f7f, 0xee6ed178, 0x06f067aa, 0x72176fba,
+    0x0a637dc5, 0xa2c898a6, 0x113f9804, 0xbef90dae, 0x1b710b35, 0x131c471b,
+    0x28db77f5, 0x23047d84, 0x32caab7b, 0x40c72493, 0x3c9ebe0a, 0x15c9bebc,
+    0x431d67c4, 0x9c100d4c, 0x4cc5d4be, 0xcb3e42b6, 0x597f299c, 0xfc657e2a,
+    0x5fcb6fab, 0x3ad6faec, 0x6c44198c, 0x4a475817,
+}
+
+--- Hashes data bytes using SHA512.
+--- @param data string The input data.
+--- @return string hash The 64-byte hash value.
+local function digest(data)
+    expect(1, data, "string")
+
+    -- Pad input.
+    local bitlen = #data * 8
+    local padlen = -(#data + 17) % 128
+    data = data .. "\x80" .. ("\0"):rep(padlen) .. p1x16(fmt1x16, bitlen)
+
+    -- Initialize state.
+    local h01, h00 = 0x6a09e667, 0xf3bcc908
+    local h11, h10 = 0xbb67ae85, 0x84caa73b
+    local h21, h20 = 0x3c6ef372, 0xfe94f82b
+    local h31, h30 = 0xa54ff53a, 0x5f1d36f1
+    local h41, h40 = 0x510e527f, 0xade682d1
+    local h51, h50 = 0x9b05688c, 0x2b3e6c1f
+    local h61, h60 = 0x1f83d9ab, 0xfb41bd6b
+    local h71, h70 = 0x5be0cd19, 0x137e2179
+
+    -- Digest.
+    for i = 1, #data, 128 do
+        local w = {u32x4(fmt32x4, data, i)}
+
+        -- Message schedule.
+        for j = 33, 160, 2 do
+            local wf1, wf0 = w[j - 30], w[j - 29]
+            local t1 = shr(wf1, 1) + shl(wf0, 31)
+            local t0 = shr(wf0, 1) + shl(wf1, 31)
+            local u1 = shr(wf1, 8) + shl(wf0, 24)
+            local u0 = shr(wf0, 8) + shl(wf1, 24)
+            local v1 = shr(wf1, 7)
+            local v0 = shr(wf0, 7) + shl(wf1, 25)
+
+            local w21, w20 = w[j - 4], w[j - 3]
+            local w1 = shr(w21, 19) + shl(w20, 13)
+            local w0 = shr(w20, 19) + shl(w21, 13)
+            local x0 = shr(w21, 29) + shl(w20, 3)
+            local x1 = shr(w20, 29) + shl(w21, 3)
+            local y1 = shr(w21, 6)
+            local y0 = shr(w20, 6) + shl(w21, 26)
+
+            local r1, r0 =
+                w[j - 32] + bxor(t1, u1, v1) + w[j - 14] + bxor(w1, x1, y1),
+                w[j - 31] + bxor(t0, u0, v0) + w[j - 13] + bxor(w0, x0, y0)
+
+            w[j], w[j + 1] = carry64(r1, r0)
+        end
+
+        -- Block function.
+        local a1, a0 = h01, h00
+        local b1, b0 = h11, h10
+        local c1, c0 = h21, h20
+        local d1, d0 = h31, h30
+        local e1, e0 = h41, h40
+        local f1, f0 = h51, h50
+        local g1, g0 = h61, h60
+        local h1, h0 = h71, h70
+        for j = 1, 160, 2 do
+            local t1 = shr(e1, 14) + shl(e0, 18)
+            local t0 = shr(e0, 14) + shl(e1, 18)
+            local u1 = shr(e1, 18) + shl(e0, 14)
+            local u0 = shr(e0, 18) + shl(e1, 14)
+            local v0 = shr(e1, 9) + shl(e0, 23)
+            local v1 = shr(e0, 9) + shl(e1, 23)
+            local s11 = bxor(t1, u1, v1)
+            local s10 = bxor(t0, u0, v0)
+
+            local ch1 = bxor(band(e1, f1), band(bnot(e1), g1))
+            local ch0 = bxor(band(e0, f0), band(bnot(e0), g0))
+
+            local temp11 = h1 + s11 + ch1 + K[j] + w[j]
+            local temp10 = h0 + s10 + ch0 + K[j + 1] + w[j + 1]
+
+            local w1 = shr(a1, 28) + shl(a0, 4)
+            local w0 = shr(a0, 28) + shl(a1, 4)
+            local x0 = shr(a1, 2) + shl(a0, 30)
+            local x1 = shr(a0, 2) + shl(a1, 30)
+            local y0 = shr(a1, 7) + shl(a0, 25)
+            local y1 = shr(a0, 7) + shl(a1, 25)
+            local s01 = bxor(w1, x1, y1)
+            local s00 = bxor(w0, x0, y0)
+
+            local maj1 = bxor(band(a1, b1), band(a1, c1), band(b1, c1))
+            local maj0 = bxor(band(a0, b0), band(a0, c0), band(b0, c0))
+
+            local temp21 = s01 + maj1
+            local temp20 = s00 + maj0
+
+            h1 = g1  h0 = g0
+            g1 = f1  g0 = f0
+            f1 = e1  f0 = e0
+            e1, e0 = carry64(d1 + temp11, d0 + temp10)
+            d1 = c1  d0 = c0
+            c1 = b1  c0 = b0
+            b1 = a1  b0 = a0
+            a1, a0 = carry64(temp11 + temp21, temp10 + temp20)
+        end
+
+        h01, h00 = carry64(h01 + a1, h00 + a0)
+        h11, h10 = carry64(h11 + b1, h10 + b0)
+        h21, h20 = carry64(h21 + c1, h20 + c0)
+        h31, h30 = carry64(h31 + d1, h30 + d0)
+        h41, h40 = carry64(h41 + e1, h40 + e0)
+        h51, h50 = carry64(h51 + f1, h50 + f0)
+        h61, h60 = carry64(h61 + g1, h60 + g0)
+        h71, h70 = carry64(h71 + h1, h70 + h0)
+    end
+
+    return p16x4(fmt16x4,
+        h01, h00, h11, h10, h21, h20, h31, h30,
+        h41, h40, h51, h50, h61, h60, h71, h70
+    )
+end
+
+return {
+    digest = digest,
+}

ccryptolib/x25519c.lua

@@ -22,7 +22,7 @@ end
 --- Masks a signature secret key.
 --- @param sk string A random 32-byte Edwards25519 secret key.
 --- @return string msk A masked secret key.
-function maskS(sk)
+local function maskS(sk)
     expect(1, sk, "string")
     lassert(#sk == 32, "secret key length must be 32", 2)
     return mask(sha512.digest(sk):sub(1, 32))

example/encrypted_chat/README.md

@@ -0,0 +1,3 @@
+# E2EE P2P RedNet chat.
+This ones a hot mess, apologies for that.
+Uses ed25519 keys to get a shared key that isn't transmitted, used to encrypt messages with chacha20

example/encrypted_chat/encchat.lua

@@ -0,0 +1,205 @@
+term.clear()
+term.setCursorPos(1, 1)
+-- Find modems
+for _, sModem in ipairs(peripheral.getNames()) do
+    if peripheral.getType(sModem) == "modem" then rednet.open(sModem) end
+end
+
+local knownHosts = settings.get("knownhosts")
+if knownHosts == nil then
+	settings.set("knownhosts", {})
+	settings.save()
+end
+
+local isClient = true
+local PK = nil
+local crypto = require("ccryptolib")
+crypto.random.initWithTiming()
+local to = arg[1] -- Who we're trying to talk to (computer id)
+write("Your Nickname: ")
+local from = read()
+if to == nil then print("You need to provide a computer ID!") end
+local hexPrivate = settings.get("keys.private")
+local hexPublic = settings.get("keys.public")
+
+if hexPrivate == nil then
+    settings.set("keys.private", crypto.util.toHex(crypto.random.random(32)))
+    hexPrivate = settings.get("keys.private")
+	settings.save()
+end
+
+if hexPublic == nil then
+	settings.set("keys.public", crypto.util.toHex(crypto.x25519.publicKey(crypto.util.fromHex(settings.get("keys.private")))))
+	hexPublic = settings.get("keys.public")
+    settings.save()
+end
+
+local privateKey = crypto.util.fromHex(hexPrivate)
+local publicKey = crypto.util.fromHex(hexPublic)
+
+local termX, termY = term.getSize()
+
+function string.starts(String, Start)
+    return string.sub(String, 1, string.len(Start)) == Start
+end
+
+function rx()
+    while true do
+        sleep(0)
+        sender, rawData = rednet.receive("encChat")
+        if sender ~= tonumber(to) then return end
+        data = textutils.unserialise(crypto.chacha20.crypt(PK, rawData.nonce, rawData.data))
+        if not data.test then return end -- Failed decrypt, possible bad key exchange?
+        term.setCursorPos(1, termY)
+        term.clearLine()
+        print(data.from .. ":" .. data.msg)
+		term.blit("> ", "30", "ff")
+        term.setCursorPos(3, termY)
+    end
+end
+
+function tx()
+    while true do
+        sleep(0)
+        term.setCursorPos(1, termY)
+        term.blit("> ", "30", "ff")
+        local msg = read()
+        if (string.starts(msg, "/")) then
+            -- Command handler
+			msg = string.lower(msg)
+			if msg == ("/q" or "/quit" or "/exit") then
+				error("Goodbye!")
+			end
+        else
+            term.scroll(-1)
+            term.clearLine()
+            write(from .. ":" .. msg)
+            term.scroll(1)
+            nonce = crypto.random.random(12)
+            msgData = {
+                timestamp = os.epoch("utc"),
+                msg = msg,
+                from = from,
+                test = true
+            }
+            rednet.send(tonumber(to), {
+                nonce = nonce,
+                data = crypto.chacha20
+                    .crypt(PK, nonce, textutils.serialise(msgData))
+            }, "encChat")
+        end
+    end
+end
+
+function ping()
+    local fails = 0
+    if isClient then
+        while true do
+            sleep(1)
+            nonce = crypto.random.random(12)
+            msgData = {timestamp = os.epoch("utc"), test = true}
+            rednet.send(tonumber(to), {
+                nonce = nonce,
+                data = crypto.chacha20
+                    .crypt(PK, nonce, textutils.serialise(msgData))
+            }, "encPing")
+
+            -- Wait for reply
+            sender, reply = rednet.receive("encPingReply", 5)
+            if fails > 2 then
+                error(
+                    "No response from other user, They likely closed their client exiting...")
+            end
+            if sender == nil or data == nil then
+                fails = fails + 1
+            elseif crypto.chacha20.crypt(PK, reply.nonce, reply.data) ~=
+                tostring(msgData.timestamp) then
+                error("Invalid reply from ping, exiting for security.")
+            else
+                fails = 0
+            end
+        end
+    else
+        while true do
+            sleep(1)
+            sender, data = rednet.receive("encPing", 10)
+            if fails > 1 then
+                error("No response from other user, They likely closed their client exiting...")
+            end
+            if sender == nil or data == nil then
+                fails = fails + 1
+            elseif sender == tonumber(to) then
+                timestamp = textutils.unserialise(crypto.chacha20.crypt(PK, data.nonce, data.data)).timestamp
+                if os.epoch("utc") > timestamp then
+                    fails = 0
+                    local nonce = crypto.random.random(12)
+                    rednet.send(sender, {
+                        nonce = nonce,
+                        data = crypto.chacha20
+                            .crypt(PK, nonce, tostring(timestamp))
+                    }, "encPingReply")
+                end
+            end
+        end
+    end
+end
+
+function exchange()
+    print("sending ping to " .. to)
+    rednet.send(tonumber(to), publicKey, "keyExClient")
+    sender, data = rednet.receive("keyEx", 1)
+    if sender ~= tonumber(to) then -- Switch to server
+        print("no response from " .. to .. ". listening for ping...")
+        isClient = false
+        while true do
+            sender, data = rednet.receive("keyExClient")
+            if sender == tonumber(to) then
+                print("ping from " .. sender .. ". sending and generating keys...")
+                rednet.send(tonumber(to), publicKey, "keyEx")
+				if knownHosts[tonumber(to)] == nil then
+					write("remote pubkey is " .. crypto.util.toHex(data) ..". Do you trust it? (Y/N)")
+					local trust = string.lower(read())
+					if trust == "y" then
+						knownHosts[tonumber(to)] = data
+						settings.set("knownhosts", knownHosts)
+						settings.save()
+						PK = crypto.x25519.exchange(privateKey, data)
+					else
+						error("Exiting...")
+					end
+				elseif knownHosts[tonumber(to)] ~= data then
+					error("==DANGER== Remote pubkey differs from previous interaction!")
+				else
+					PK = crypto.x25519.exchange(privateKey, data)
+				end
+                break
+            end
+        end
+    else
+        print("response from " .. to)
+		if knownHosts[tonumber(to)] == nil then
+			write("remote pubkey is " .. crypto.util.toHex(data) ..". Do you trust it? (Y/N)")
+			local trust = string.lower(read())
+			if trust == "y" then
+				knownHosts[tonumber(to)] = data
+				settings.set("knownhosts", knownHosts)
+				settings.save()
+				PK = crypto.x25519.exchange(privateKey, data)
+			else
+				error("Exiting...")
+			end
+		elseif knownHosts[tonumber(to)] ~= data then
+			error("==DANGER== Remote pubkey differs from previous interaction!")
+		else
+			PK = crypto.x25519.exchange(privateKey, data)
+		end
+        PK = crypto.x25519.exchange(privateKey, data)
+    end
+	term.clear()
+	term.setCursorPos(1,1)
+    print("==BEGIN ENCRYPTED CONVERSATION==")
+end
+
+exchange()
+
+parallel.waitForAll(rx, tx, ping)

example/secure_login/README.md

@@ -0,0 +1,4 @@
+# SHA-512 hashed login system
+This is a really simple setup to secure a computer in computercraft from them pesky fuckers in your server :P
+
+Multi user support, but no separation of files or any file permissions at all for that matter. i.e if someone can log in, they can disable the login and change passwords, beware.

example/secure_login/passwd.lua

@@ -0,0 +1,28 @@
+local username = arg[1] or _G.loggedInUser
+local passwdData = settings.get("passwd")
+
+if passwdData[username] == nil then
+	error("passwd: user '" .. username .. "' does not exist")
+end
+
+local crypto = require("ccryptolib")
+crypto.random.initWithTiming()
+
+print("Changing password for " .. username .. ".")
+write("New password: ")
+local pwd1 = crypto.sha512.digest(read(""))
+write("Retype new password: ")
+local pwd2 = crypto.sha512.digest(read(""))
+
+if pwd1 ~= pwd2 then
+	error("Sorry, passwords do not match.")
+end
+
+if pwd1 == passwdData[username] then
+	error("The password has not been changed.")
+end
+
+passwdData[username] = crypto.util.toHex(pwd1)
+settings.set("passwd", passwdData)
+settings.save()
+print("passwd: password updated successfully")

example/secure_login/startup.lua

@@ -0,0 +1,46 @@
+-- No term for you :)
+Original_pullEvent = os.pullEvent
+os.pullEvent = os.pullEventRaw
+settings.set("shell.allow_disk_startup", false) -- Prevent disk startup bypass
+-- Header stuff
+local hostname = os.getComputerLabel() or "craftos"
+term.clear()
+term.setCursorPos(1,1)
+write(_G._ENV._HOST .. " " .. hostname)
+
+-- Load crypto library (slow, so we do it after everything else)
+Crypto = require("ccryptolib")
+Crypto.random.initWithTiming()
+
+function checkCreds(username, hashed)
+
+	if Crypto.util.fromHex(settings.get("passwd")[username]) == hashed then
+		return true
+	else
+		return false
+	end
+end
+
+function login()
+	print()
+	write(hostname .. " login: ")
+	local username = read()
+	write("Password: ")
+	local passwordHash = Crypto.sha512.digest(read("")) -- Hash immidiately so password is not stored plaintext in memory
+	if checkCreds(username, passwordHash) then
+		print("Welcome ".. username)
+		_G.loggedInUser = username
+	else
+		print("Login incorrect")
+		login()
+	end
+end
+
+if not settings.get("passwd") then
+	print()
+	print("WARNING: passwd file does not exist, generating default login root:toor")
+	settings.set("passwd", { ["root"] = Crypto.util.toHex(Crypto.sha512.digest("toor")) })
+	settings.save()
+end
+
+login()

example/secure_login/useradd.lua

@@ -0,0 +1,28 @@
+local username = arg[1]
+local passwdData = settings.get("passwd")
+
+if passwdData[username] then
+	error("useradd: user '" .. username .."' already exists")
+end
+
+local crypto = require("ccryptolib")
+crypto.random.initWithTiming()
+
+print("Changing password for " .. username .. ".")
+write("New password: ")
+local pwd1 = crypto.sha512.digest(read(""))
+write("Retype new password: ")
+local pwd2 = crypto.sha512.digest(read(""))
+
+if pwd1 ~= pwd2 then
+	error("Sorry, passwords do not match.")
+end
+
+if pwd1 == passwdData[username] then
+	error("The password has not been changed.")
+end
+
+passwdData[username] = crypto.util.toHex(pwd1)
+settings.set("passwd", passwdData)
+settings.save()
+print("useradd: password updated successfully")

install.lua

@@ -0,0 +1,18 @@
+fs.makeDir("/ccryptolib") -- Make folder structure
+
+function downloadDir(dir)
+	local data = textutils.unserialiseJSON(http.get("https://git.chrischro.me/api/v1/repos/ChrisChrome/ccryptolib/contents/" .. dir).readAll())
+	for _,entry in ipairs(data) do
+		if entry.type == "file" then -- We're gonna download it
+			print("Downloading " .. entry.name)
+			local file = http.get(entry.download_url).readAll()
+			local newFile = fs.open("/" .. entry.path, "w")
+			newFile.write(file)
+			newFile.close()
+		elseif entry.type == "dir" then
+			downloadDir(entry.path)
+		end
+	end
+end
+
+downloadDir("ccryptolib")