Re: [TLS] is it good using password for authentication only?

Hi,

On 6/19/15 13:03, Bingzheng Wu wrote:
> I am wrong again. Adding master-secret is useless.
>
> Now I think that asymmetric crypto must be used to prevent offline directory attack, which is the way PAKE works as.
>
I'm probably wrong since I only thought about it for a few minutes, but 
it seems to me that the PasswordVerify message would be encrypted with 
(keys derived from) the handshake master secret, which would prevent 
offline attacks.

What am I missing?

> Sorry for disturbing.
>
Probably sorry too :)

Manuel.

> ------------------------------------------------------------------
> From:武炳正(允中) <bingzheng.wbz@alibaba-inc.com>
> Time:2015 Jun 19 (Fri) 16:19
> To:武炳正(允中) <bingzheng.wbz@alibaba-inc.com>, tls <tls@ietf.org>
> Subject:RE: [TLS] is it good using password for authentication only?
>
> Maybe I realize the problem. The PasswordVerify message is susceptible to
> offline dictionary attacks.
>
> Dose it become resistant to the attack if we add some secret generated from
> master-secret into the HASH?
>
>    PasswordVerify = HASH(username, passward, handshake_message_hash,
> master-secret, label)
>
> This becomes involved with key-exchange, but it is not involved with any
> specific key-exchange method.
> It just need the key-exchange result.
>
>
> Bingzheng
>
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