<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class="">Great thoughts guys, appreciate it. </div><div class=""><br class=""></div><div class="">AWS does not have a built in RADIUS server (maybe..only did a quick search) so I have to think about service reliability (scalable, backup, resilience, etc). It does have Active Directory though if thats a replaceable solution.</div><div class=""><br class=""></div><div class="">So the problem is that the MSCHAP Response from the client is an md4 hash of the password, which is a weak hash so even storing the plaintext as an md4 hash is insecure...</div><div class=""><br class=""></div><div class="">but what if the server stored the password in a sha256(md4(password)) hash and then when it received the md4 hash from the client, hashed that with sha256 to compare to?</div><div class=""><br class=""></div><div class="">The Server can send any fake md4 hash across the network to the client (unless the client does its own check of the hash)...</div><div class=""><br class=""></div><div class="">< send md4(anything)</div><div class="">> recv md4(password)</div><div class=""># hash md4(password) with sha256 and compare to locally stored hash</div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">[1] <a href="https://tools.ietf.org/html/rfc2759" class="">https://tools.ietf.org/html/rfc2759</a></div><div class="">[2] <a href="http://www.arubanetworks.com/techdocs/ClearPass/Aruba_DeployGd_HTML/Content/A 802.1X EAP-PEAP Reference/EAP_PEAP_handshake.htm" class="">http://www.arubanetworks.com/techdocs/ClearPass/Aruba_DeployGd_HTML/Content/A%20802.1X%20EAP-PEAP%20Reference/EAP_PEAP_handshake.htm</a></div><div class="">[3] <a href="http://manpages.ubuntu.com/manpages/xenial/man5/shadow.5.html" class="">http://manpages.ubuntu.com/manpages/xenial/man5/shadow.5.html</a></div><br class=""><div><blockquote type="cite" class=""><div class="">On 9 May 2018, at 21:31, Thor Simon <<a href="mailto:Thor.Simon@twosigma.com" class="">Thor.Simon@twosigma.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">At the expense of reducing the strength of your authentication (and potentially the confidentiality of your passwords) to that of an ad-hoc stream cipher based on MD5 -- unless you encapsulate RADIUS in something else, which adds some complexity but would work.<br class=""><br class="">-----Original Message-----<br class="">From: Users <<a href="mailto:users-bounces@lists.strongswan.org" class="">users-bounces@lists.strongswan.org</a>> On Behalf Of Tony Hoyle<br class="">Sent: Wednesday, May 9, 2018 4:06 PM<br class="">To: <a href="mailto:users@lists.strongswan.org" class="">users@lists.strongswan.org</a><br class="">Subject: Re: [strongSwan] Authentication against Linux Users<br class=""><br class="">On 09/05/2018 16:17, Christian Salway wrote:<br class=""><blockquote type="cite" class="">Unfortunately IKEv2 is a requirement, and they have requested <br class="">username/password authentication because they don't like the "struggles"<br class="">of installed a CA cert and a client cert.<br class=""><br class="">Currently the authentication is done with MSCHAPv2 which requires SS <br class="">to have a plain text copy of the password in order to create the <br class="">Challenge hash, I understand that.... however, what if SS was able to <br class="">retrieve the plain text password from another source other than a <br class="">local config file, eg Amazon's SecretsManager for example? Is this <br class="">something that is available or that you guys could write (at a price Im sure)?<br class=""><br class=""></blockquote>If you migrate all the password information into a radius server, that can handle both linux and strongswan login.<br class=""><br class="">Tony<br class=""></div></div></blockquote></div><br class=""></body></html>