<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta content="text/html;charset=UTF-8" http-equiv="Content-Type"></head><body ><br><meta http-equiv="content-type" content="text/html; charset=utf-8"><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">Main question: is it safe, to open a port for an openssl server? </span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">e.g.:</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">server side - generate a self-signed cert.</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">time openssl req -x509 -nodes -days 365 -newkey rsa:8192 -keyout mycert.pem -out mycert.pem</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">openssl s_server -accept 52310 -cert mycert.pem</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">Is it secure? - it could be DOSed' [DenialofService] or could it be attacked in any way?</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">Are there any iptables rule for restricting connections to dyndns names?</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">e.g.: only allow connection from "asdfasdf.dyndns.com" and "asdfasdf2.dyndns.com" and "asdfasdf3.dyndns.com"?</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">How could i restrict the openssl server to only accept traffic from given clients? Please help me "think"..</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">Or are there any "production ready" methods, that can do authentication too? [+using ssl].</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">"openssl s_server" and "openssl s_client" would be perfect, but the problem is it doesn't has username/password auth :\</span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div><div style="font-family: 'Times New Roman'; font-size: medium; "><font class="Apple-style-span" face="Verdana, Arial, Helvetica, sans-serif"><span class="Apple-style-span" style="font-size: 12px; ">Thank you for any help.</span></font></div><div id=""></div></body></html>