On Tue, Mar 4, 2014 at 11:19 AM, Dr. Stephen Henson <[email protected]> wrote:
> On Tue, Mar 04, 2014, Jeffrey Walton wrote:
>
>> On Tue, Mar 4, 2014 at 9:02 AM, Viktor Dukhovni
>> <[email protected]> wrote:
>> > On Tue, Mar 04, 2014 at 06:35:13AM -0500, Jeffrey Walton wrote:
>> >
>> >> I've got a server that can't negotiate a cipher suite with a client
>> >> when using ECDSA certificates. When using ECDSA, the server reports
>> >> 0x1408a0c1 (no shared cipher).
>> >
>> > Did you configure an EECDH (aka ECDHE) curve? With OpenSSL 1.0.[01],
>> > the more common ECDSA cipher-suites use kEECDH key agreement.
>> Yes. The server's preferred cipher list is:
>>
>> static const char PREFERRED_CIPHERS[] =
>> "ECDHE-ECDSA-AES256-GCM-SHA384:"
>> "ECDHE-ECDSA-AES128-GCM-SHA256:"
>> "ECDHE-RSA-AES256-GCM-SHA384:"
>> "ECDHE-RSA-AES128-GCM-SHA256:"
>> "DHE-RSA-AES256-GCM-SHA384:"
>> "DHE-RSA-AES128-GCM-SHA256:"
>> "DHE-RSA-AES256-SHA:"
>> "DHE-RSA-AES128-SHA:"
>> "EDH-RSA-DES-CBC3-SHA:"
>> "DH-RSA-DES-CBC3-SHA";
>>
>
> Silly question time . Viktor asked if you'd set an ECDHE curve and you
> responded saying yes and a list of ciphersuites which by themselves don't
> set a curve.
>
> So just to double check: you did set a temporary curve parameters using
> something like SSL_CTX_set_tmp_ecdh?
This is in the server's context setup code:
SSL_CTX_set_tmp_dh_callback(ctx, DH_callback);
SSL_CTX_set_tmp_ecdh_callback(ctx, ECDH_callback);
And:
EC_KEY* ECDH_callback(SSL *ssl, int is_export, int keylength)
{
return ECDH256();
}
Finally:
static EC_KEY* ECDH256()
{
EC_KEY* key = EC_KEY_new_by_curve_name(NistCurveToNidByBits(256));
unsigned long err = ERR_get_error();
...
return key;
}
NistCurveToNidByBits(256) returns NID_X9_62_prime256v1. I also tried
returning NID_secp256k1 with the same result.
I'm setting up Wireshark now on another machine to get the trace.
Jeff
______________________________________________________________________
OpenSSL Project http://www.openssl.org
User Support Mailing List [email protected]
Automated List Manager [email protected]
