Ddos site through registration?

Question

linux

Hello, I ran into such a problem that my site is "ddosed" through different forms. For example, when registering, many million characters are indicated, and the database falls down. In this case, maxlength is easily bypassed. Is it possible to fix this with limits in Nginx? If so, which ones?

Answer 1

maxlength bypasses direct requests, reduce the size of the maximum post, get in php.ini
In general, install and configure iptables, judging by the tactics, some kind of noob ddos ​​you

Answer 2

Rule number # - users cannot be trusted, even authorized ones. Server side validation is required.