【入门夯实】连接认证：握手阶段的基础校验写法

local function onHandshake(conn, token)
    attachSession(conn, token)
    sendmsg(nil, 1, "连接已建立")
end

local sessions = {}
local function onHandshake(conn, token, ts)
    if type(token) ~= "string" or #token ~= 16 then
        return false
    end
    if sessions[token] == nil then
        return false
    end
    local now = os.time()
    if math.abs(now - ts) > 30 then
        return false
    end
    attachSession(conn, token)
    sessions[token].conn = conn
    sendmsg(nil, 1, "连接认证通过")
    return true
end

local fails = {}
local function noteFail(source)
    fails[source] = (fails[source] or 0) + 1
    return fails[source] >= 5
end