linux-kernel - Re: [PATCH net-next] ipmr: ip6mr: Create new sockopt to clear mfc cache or vifs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 8 Feb 2019 16:43:57 +0200
From:   Nikolay Aleksandrov <nikolay@...ulusnetworks.com>
To:     nicolas.dichtel@...nd.com,
        Callum Sinclair <callum.sinclair@...iedtelesis.co.nz>,
        davem@...emloft.net, kuznet@....inr.ac.ru, yoshfuji@...ux-ipv6.org,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next] ipmr: ip6mr: Create new sockopt to clear mfc
 cache or vifs

On 08/02/2019 16:18, Nicolas Dichtel wrote:
> Le 08/02/2019 à 05:11, Callum Sinclair a écrit :
>> Currently the only way to clear the mfc cache was to delete the entries
> mfc stands for 'multicast forwarding cache', so 'mfc cache' is a bit strange.
> 
>> one by one using the MRT_DEL_MFC socket option or to destroy and
>> recreate the socket.
> Note that if entries were added with MRT_ADD_MFC_PROXY, they will survive to the
> socket destruction. This is not the case with your new cmd. Is it intended?

I think you're referring to MFC_STATIC entries (sk != mroute_sk). It
doesn't matter how you add an entry - they all get cleaned up if added
through the mroute socket.

> Maybe a third option (something like MRT_FLUSH_MFC_PROXY) would be useful to
> avoid confusion?
> 
>>
>> Create a new socket option which will clear the multicast forwarding
>> cache on the socket without destroying the socket. The new socket option
>> MRT_FLUSH_ENTRIES will clear all multicast entries on the sockets table
>> and the MRT_FLUSH_VIFS will delete all multicast vifs on the socket
>> table.
>>
>> Signed-off-by: Callum Sinclair <callum.sinclair@...iedtelesis.co.nz>
>> ---
>>  include/uapi/linux/mroute.h  |  7 +++-
>>  include/uapi/linux/mroute6.h |  7 +++-
>>  net/ipv4/ipmr.c              | 69 ++++++++++++++++++++-------------
>>  net/ipv6/ip6mr.c             | 74 ++++++++++++++++++++++--------------
>>  4 files changed, 100 insertions(+), 57 deletions(-)
>>
>> diff --git a/include/uapi/linux/mroute.h b/include/uapi/linux/mroute.h
>> index 5d37a9ccce63..673495ca3495 100644
>> --- a/include/uapi/linux/mroute.h
>> +++ b/include/uapi/linux/mroute.h
>> @@ -28,12 +28,17 @@
>>  #define MRT_TABLE	(MRT_BASE+9)	/* Specify mroute table ID		*/
>>  #define MRT_ADD_MFC_PROXY	(MRT_BASE+10)	/* Add a (*,*|G) mfc entry	*/
>>  #define MRT_DEL_MFC_PROXY	(MRT_BASE+11)	/* Del a (*,*|G) mfc entry	*/
>> -#define MRT_MAX		(MRT_BASE+11)
>> +#define MRT_FLUSH	(MRT_BASE+12)	/* Flush all multicast entries and vifs	*/
> nit: "Flush all mfc entries and/or vifs" ?
> 
>> +#define MRT_MAX		(MRT_BASE+12)
>>  
>>  #define SIOCGETVIFCNT	SIOCPROTOPRIVATE	/* IP protocol privates */
>>  #define SIOCGETSGCNT	(SIOCPROTOPRIVATE+1)
>>  #define SIOCGETRPF	(SIOCPROTOPRIVATE+2)
>>  
>> +/* MRT_FLUSH optional flags */
>> +#define MRT_FLUSH_ENTRIES	1	/* For flushing all multicast entries */
> Maybe MRT_FLUSH_MFC is more consistent with the previous naming (MRT_ADD_MFC, etc.)
> 
> 
> Regards,
> Nicolas
>