<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class=""><br class="">
</div><div class="">Thanks. answers inline</div><div class=""><br class=""></div>
<div><br class=""><blockquote type="cite" class=""><div class="">On 19 Jul 2018, at 09:38, Tobias Brunner <<a href="mailto:tobias@strongswan.org" class="">tobias@strongswan.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">Hi Christian,<br class=""><br class=""><blockquote type="cite" class="">I am also<br class="">limited to the native OSX/Windows VPN clients which currently support a<br class="">maximum of aes256-sha256-prfsha256-ecp256-modp2048 (Windows does not<br class="">support ecp)<br class=""></blockquote><br class="">It does (at least on Windows 10), you just have to enable it via<br class="">PowerShell (see [1]).<br class=""></div></div></blockquote><div><br class=""></div><div>Even with the registry key added, the IKE ciphers are as follows:</div><div><br class=""></div><div>WINDOWS 10</div><div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:AES_CBC_256/HMAC_SHA1_96/PRF_HMAC_SHA1/MODP_2048</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:AES_CBC_256/HMAC_SHA2_256_128/PRF_HMAC_SHA2_256/MODP_2048</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:AES_CBC_256/HMAC_SHA2_384_192/PRF_HMAC_SHA2_384/MODP_2048</span></div></div><div><br class=""></div><div>ie, no ECP and annoyingly weakest first!</div><div><br class=""></div><div>OSX</div><div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:AES_CBC_256/HMAC_SHA2_256_128/PRF_HMAC_SHA2_256/MODP_2048,</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:AES_CBC_256/HMAC_SHA2_256_128/PRF_HMAC_SHA2_256/ECP_256,</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:AES_CBC_256/HMAC_SHA2_256_128/PRF_HMAC_SHA2_256/MODP_1536,</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:AES_CBC_128/HMAC_SHA1_96/PRF_HMAC_SHA1/MODP_1024,</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">IKE:3DES_CBC/HMAC_SHA1_96/PRF_HMAC_SHA1/MODP_1024</span></div></div><div><br class=""></div><br class=""><blockquote type="cite" class=""><div class=""><div class=""><blockquote type="cite" class="">Apart from IPSEC being Layer 3 and HTTP being Layer 6, meaning that<br class="">should a VPN client be infected with a worm, it is easier for that worm<br class="">to infect the network, I’m struggling to see another security argument.<br class=""></blockquote><br class="">Probably depends on the IPsec policies (e.g. if split tunneling is used<br class="">or even only single protocols/ports are allowed) and the firewall rules<br class="">on the remote end vs. what is available via HTTPS connection (e.g. if<br class="">the latter creates a VPN too or the malware can hijack the VDI somehow).<br class=""></div></div></blockquote><div><br class=""></div><div>Split tunneling and select ports, but it is still easier for a worm to go down an IP than over VDI</div><br class=""><blockquote type="cite" class=""><div class=""><div class=""><br class=""><blockquote type="cite" class="">Data encrypted over RSA 4096 SHA-2 on paper seems a secure connection.<br class=""></blockquote><br class="">Nobody encrypts large amounts of data via RSA, if anything it's used to<br class="">encrypt a symmetric key that's then used to encrypt the data, but mostly<br class="">only for authentication (digital signatures). The key exchange usually<br class="">happens via ephemeral DH (in IKE always and nowadays in TLS too).<br class=""></div></div></blockquote><div><br class=""></div><blockquote type="cite" class=""><div class=""><div class=""><br class=""><blockquote type="cite" class=""> Whereas IKE also uses a certificate to do the KeyExchange before<br class="">logging in <br class=""></blockquote><br class="">No, the key exchange is done via DH, the certificate is used for<br class="">authentication only (to prevent MITM attacks).<br class=""><br class=""><blockquote type="cite" class="">and then encrypting the data with ESP, so the ciphers used on<br class="">ESP I feel is the comparison that needs to be made.<br class=""></blockquote><br class="">The cryptographic strength of all ciphers in a cipher suite should be<br class="">consistent. For instance, using AES-256 for ESP is basically wasted<br class="">when using MODP-2048 because that has only an estimated strength of 112<br class="">bits (same for ECP-256 whose estimated strength is 128 bits).<br class=""></div></div></blockquote><div><br class=""></div><div><br class=""></div><div>Clearly the few points above tells me I need to understand how the secure cycle works.. any good websites that can explain HTTPS and IKE/IPSEC? </div><br class=""><blockquote type="cite" class=""><div class=""><div class=""><br class=""><blockquote type="cite" class="">I will have a read of that Cipher suites page, but if I remember<br class="">correctly, it is not a comparison but a standpoint.<br class=""></blockquote><br class="">It mainly documents the available options (there are some warnings/notes<br class="">though). [2] has some general pointers regarding the security of<br class="">IKE/IPsec connections.<br class=""><br class="">Regards,<br class="">Tobias<br class=""><br class="">[1]<br class=""><a href="https://wiki.strongswan.org/projects/strongswan/wiki/WindowsClients#AES-256-CBC-and-MODP2048" class="">https://wiki.strongswan.org/projects/strongswan/wiki/WindowsClients#AES-256-CBC-and-MODP2048</a><br class="">[2]<br class="">https://wiki.strongswan.org/projects/strongswan/wiki/SecurityRecommendations<br class=""></div></div></blockquote></div><br class=""></body></html>