safe renegotiation bug?
simon at josefsson.org
Fri May 28 09:07:50 CEST 2010
Nikos Mavrogiannopoulos <nmav at gnutls.org> writes:
> Simon Josefsson wrote:
>> Nikos Mavrogiannopoulos <nmav at gnutls.org> writes:
>>> Simon Josefsson wrote:
>>>> I have added tests/safe-renegotiation/srn5.c in which a client with
>>>> support for safe reneg connect to a server without support for safe
>>>> reneg. The handshake succeeds (as expected), however the call to
>>>> gnutls_safe_renegotiation_status in the server, after the handshake,
>>>> indicates that the session is using safe renegotiation -- this seems
>>>> like a bug to me. Nikos/Steve, could you take a look?
>>> Should be ok now. I get aborts in the srn5 but they seem intended?
>> I fixed that now -- however it seems there is another problem, now the
>> rehandshake succeeds against a server that doesn't support safe
>> renegotiation. The second handshake in srn5 should fail, shouldn't it?
> By default server is on unsafe renegotiation mode and doesn't require
> any of the extensions, either on the first or subsequent negotiations.
> Disallowing rengotiations after this point for the client shouldn't
> offer any advantage since you are already connected securely to a peer.
But this self tests is with a server that has safe renegotiation
disabled, see tests/safe-renegotiation/srn5.c.
The client by default permits connections, but I don't think clients
should (by default) allow renegotiation against such servers.
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