Re: [PATCH v2 5/9] ft: add ft_handshake_setup

James Prestwood
2023-12-06T16:46:50Z

Hi Denis,

On 12/6/23 08:38, Denis Kenzior wrote:
> Hi James,
>
> On 12/6/23 09:07, James Prestwood wrote:
>> This will be called from station after FT-authentication has
>> finished. It sets up the handshake object to perform reassociation.
>>
>> This is essentially a copy-paste of ft_associate without sending
>> the actual frame.
>> ---
>>   src/ft.c | 32 ++++++++++++++++++++++++++++++++
>>   src/ft.h |  2 ++
>>   2 files changed, 34 insertions(+)
>>
>> diff --git a/src/ft.c b/src/ft.c
>> index 358a4594..738e08c3 100644
>> --- a/src/ft.c
>> +++ b/src/ft.c
>> @@ -1276,6 +1276,38 @@ int ft_associate(uint32_t ifindex, const
>> uint8_t *addr)
>>       return ret;
>>   }
>>   +int ft_handshake_setup(uint32_t ifindex, const uint8_t *target)
>> +{
>> +    struct netdev *netdev = netdev_find(ifindex);
>> +    struct handshake_state *hs = netdev_get_handshake(netdev);
>> +    struct ft_info *info;
>> +
>> +    info = ft_info_find(ifindex, target);
>> +    if (!info)
>> +        return -ENOENT;
>> +
>> +    /*
>> +     * Either failed or no response. This may have been an FT-over-DS
>> +     * attempt so clear out the entry so FT-over-Air can try again.
>> +     */
>> +    if (info->status != 0) {
>> +        int status = info->status;
>> +
>> +        l_queue_remove(info_list, info);
>> +        ft_info_destroy(info);
>> +
>> +        return status;
>> +    }
>> +
>> +    if (L_WARN_ON(!ft_prepare_handshake(info, hs)))
>> +        return -EINVAL;
>
> It isn't quite clear how this case should be handled?  Would you still
> remove it from the queue and destroy this info object? Or destroy all
> authentications for the ifindex?

Hmm good point. If that fails we've already wiped the old keys from the
handshake so I don't think we could even try and roam elsewhere. This
case wasn't handled prior, we would just send the associate without
deriving the proper IEs. So I think we either need to handle this in
station and fatally fail the roam, and disconnect

I don't feel like doing it at the moment but we could create a new
handshake object too and set only after everything succeeds.

>> +    /* After this no previous auths will be valid */
>> +    ft_clear_authentications(ifindex);
>> +
>> +    return 0;
>> +}
>> +
>>   static bool remove_ifindex(void *data, void *user_data)
>>   {
>>       struct ft_info *info = data;
>
> Regards,
> -Denis
>