computercraft/auth.lua

args = { ... }

if args[1] == nil then
    io.write("Usage: auth <action>\n")
    return
end

local action = args[1]

settings.define("auth.token", {
    description = "Authentication token",
    type = "number",
    default = ""
})

settings.define("auth.server", {
    description = "Authentication server",
    type = "string",
    default = "auth.box"
})

local server = settings.get("auth.server")

function lns_lookup(hostname)
    local data = {
        ["action"] = "lookup",
        ["hostname"] = hostname
    }

    lns_server_id = rednet.lookup("lns", lns_server)
    rednet.send(lns_server_id, data)

    while true do
        id, msg = rednet.receive()
        if id == lns_server_id then
            if msg == nil then
                return nil
            else
                return msg
            end
        end
    end
end


auth_server_id = lns_lookup(server)

if action == "login" then
    io.write("Username: ")
    local username = io.read()
    io.write("Password: ")
    local password = read("*")

    local data = {
        ["action"] = "login",
        ["username"] = username,
        ["password"] = password
    }

    rednet.send(auth_server_id, data)

    while true do
        id, msg = rednet.receive()
        if id == auth_server_id then
            if msg == "invalid request" then
                io.write("Invalid request\n")
                return
            elseif msg == "user not found" then
                io.write("User not found\n")
                return
            elseif msg == "invalid password" then
                io.write("Invalid password\n")
                return
            else
                token = msg
                break
            end
        end
    end

    settings.set("auth.token", token)
    settings.save()
    io.write("Logged in as " .. username .. "\n")
    return
end

if action == "register" then
    io.write("Username: ")
    local username = io.read()
    io.write("Password: ")
    local password = read("*")
    io.write("Confirm Password: ")
    local confirm_password = read("*")

    if password ~= confirm_password then
        io.write("Passwords do not match\n")
        return
    end

    local data = {
        ["action"] = "register",
        ["username"] = username,
        ["password"] = password
    }

    rednet.send(auth_server_id, data)

    while true do
        id, msg = rednet.receive()
        if id == auth_server_id then
            if msg == "invalid request" then
                io.write("Invalid request\n")
                return
            elseif msg == "user already exists" then
                io.write("User already exists\n")
                return
            else
                io.write("Registered user " .. username .. "\n")
                return
            end
        end
    end
end