netdev - Re: [RFC net-next 1/2] net: dsa: add Realtek RTL8366S switch tag

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 for Android: free password hash cracker in your pocket

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

Message-ID: <dd9d6ce8-cd87-2612-bcc1-26df717d4e81@gmail.com>
Date:   Wed, 17 Feb 2021 12:28:39 +0100
From:   Heiner Kallweit <hkallweit1@...il.com>
To:     Linus Walleij <linus.walleij@...aro.org>
Cc:     DENG Qingfang <dqfext@...il.com>, Andrew Lunn <andrew@...n.ch>,
        Vivien Didelot <vivien.didelot@...il.com>,
        Florian Fainelli <f.fainelli@...il.com>,
        Vladimir Oltean <olteanv@...il.com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        netdev <netdev@...r.kernel.org>,
        Mauri Sandberg <sandberg@...lfence.com>
Subject: Re: [RFC net-next 1/2] net: dsa: add Realtek RTL8366S switch tag

On 17.02.2021 12:01, Linus Walleij wrote:
> On Wed, Feb 17, 2021 at 8:08 AM Heiner Kallweit <hkallweit1@...il.com> wrote:
> 
>>> +#define RTL8366S_HDR_LEN     4
>>> +#define RTL8366S_ETHERTYPE   0x8899
>>
>> I found this protocol referenced as Realtek Remote Control Protocol (RRCP)
>> and it seems to be used by few Realtek chips. Not sure whether this
>> protocol is officially registered. If yes, then it should be added to
>> the list of ethernet protocol id's in include/uapi/linux/if_ether.h.
>> If not, then it may be better to define it using the usual naming
>> scheme as ETH_P_RRCP in realtek-smi-core.h.
> 
> It's actually quite annoying, Realtek use type 0x8899 for all their
> custom stuff, including RRCP and internal DSA tagging inside
> switches, which are two completely different use cases.
> 
> When I expose raw DSA frames to wireshark it identifies it
> as "Realtek RRCP" and then naturally cannot decode the
> frames since this is not RRCP but another protocol identified
> by the same ethertype.
> 
> Inside DSA it works as we explicitly asks tells the kernel using the
> tagging code in net/dsa/tag_rtl4_a.c that this is the DSA version
> of ethertype 0x8899 and it then goes to dissect the actual
> 4 bytes tag.
> 
> There are at least four protocols out there using ethertype 0x8899.
> 

Ugly .. Thanks for the details!

> Yours,
> Linus Walleij
>