From ce84ae7ede0022f2703f966e710efacffe703348 Mon Sep 17 00:00:00 2001 From: Alexandre Derumier Date: Mon, 6 Sep 2021 05:57:20 +0200 Subject: [PATCH] sdn: add vxlan encryption notes Signed-off-by: Alexandre Derumier --- pvesdn.adoc | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/pvesdn.adoc b/pvesdn.adoc index d26c6b9..eae47ad 100644 --- a/pvesdn.adoc +++ b/pvesdn.adoc @@ -898,3 +898,55 @@ public network can reply back. If you have configured an external BGP router, the BGP-EVPN routes (10.0.1.0/24 and 10.0.2.0/24 in this example), will be announced dynamically. + + +Notes +----- + +Vxlan Encryption +~~~~~~~~~~~~~~~~ +If you need to add encryption on top of vxlan, it's possible to do it with strongswan software. +You'll need to reduce the mtu around 60bytes (ipv4) or 80bytes (ipv6) to handle encryption. + +So with default 1500 mtu, you need mtu 1370 (1370 + 80bytes ipsec + 50 bytes vxlan). + + +Install strongwan +---- +apt install strongwan +---- + +Add configuration in /etc/ipsec.conf. +(Encrypt only vxlan udp port 4789) + +---- +conn %default + ike=aes256-sha1-modp1024! #the fastest (but reasonably secure)cipher on reasonably modern hardware + esp=aes256-sha1! + leftfirewall=yes # this is necessary when using Proxmox firewall rules + +conn output + rightsubnet=%dynamic[udp/4789] + right=%any + type=transport + authby=psk + auto=route + +conn input + leftsubnet=%dynamic[udp/4789] + type=transport + authby=psk + auto=route +---- + +Then generate a preshared key with + +---- +openssl rand -base64 128 +---- + +and copy the key in /etc/ipsec.secrets + +---- +: PSK +---- -- 2.39.2