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Re: Please kill preshared key.
There are a few that do that and the reason they do is that they
want to use some legacy authentication technique to authenticate
"the client". And the reason they are forced to do this insecure
hack is because it was prohibited to add support for this type of
authentication technique directly into IKE (e.g. CRACK).
People will get what they want somehow someway. And giving someone
something they don't want will force them to look for novel (and most
likely insecure) ways to get what they want. We can make it hard to
do it wrong by making it easy to do it right.
Dan.
On Fri, 07 Dec 2001 11:20:45 EST you wrote
> The current PSK methods in IKEv1 lead to some horrible, insecure hacks
> in real
> implementations/deployments.
>
> I know of at least one VPN/Road-Warrior implementation where the server
> uses
> PSK to authenticate itself to a client--but it uses the SAME PSK for
> every
> member of a "group", where groups are very large. This means that
> anyone in
> the group can pretend to be a server to any other member of the group.
> This wouldn't happen in a self-signed PK-style pre-share. The
> client adds the PK self-signed pre-share to their "trusted" list, and
> only the real server (possessor of the private key) can convince a
> client
> of its authenticity.
>
> If symmetric PSKs are kept, it had better be possible to do it right,
> and
> rather hard to do it wrong.
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