From b3d5ca8359d3fac0f21ccece79c202557a9433b5 Mon Sep 17 00:00:00 2001 From: aszlig Date: Mon, 30 Apr 2018 05:53:38 +0200 Subject: nixos/dhparams: Set default bit size to 2048 @Ekleog writes in https://github.com/NixOS/nixpkgs/pull/39526: > I think a default of 4096 is maybe too much? See certbot/certbot#4973; > Let's Encrypt supposedly know what they are doing and use a > pre-generated 2048-bit DH params (and using the same DH params as > others is quite bad, even compared to lower bit size, if I correctly > remember the attacks available -- because it increases by as much the > value of breaking the group). > Basically I don't have anything personal against 4096, but fear it may > re-start the arms race: people like having "more security" than their > distributions, and having NixOS already having more security than is > actually useful (I personally don't know whether a real-size quantum > computer will come before or after our being able to break 2048-bit > keys, let alone 3072-bit ones -- see wikipedia for some numbers). > So basically, I'd have set it to 3072 in order to both decrease build > time and avoid having people setting it to 8192 and complaining about > how slow things are, but that's just my opinion. :) While he suggests is 3072 I'm using 2048 now, because it's the default of "openssl dhparam". If users want to have a higher value, they can still change it. Signed-off-by: aszlig --- nixos/modules/security/dhparams.nix | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'nixos/modules/security') diff --git a/nixos/modules/security/dhparams.nix b/nixos/modules/security/dhparams.nix index 481d4c5db51..beac125fc6e 100644 --- a/nixos/modules/security/dhparams.nix +++ b/nixos/modules/security/dhparams.nix @@ -10,7 +10,7 @@ let name = "bits"; description = "integer of at least 16 bits"; }; - default = 4096; + default = 2048; description = '' The bit size for the prime that is used during a Diffie-Hellman key exchange. -- cgit 1.4.1