[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <e4b500e9-f24a-43c5-c2df-834dafc3aae5@labo.rs>
Date: Mon, 5 Nov 2018 14:06:42 +0100
From: Ivan Labáth <labokml@...o.rs>
To: "Jason A. Donenfeld" <Jason@...c4.com>,
Dave Taht <dave.taht@...il.com>
Cc: LKML <linux-kernel@...r.kernel.org>,
Netdev <netdev@...r.kernel.org>,
Linux Crypto Mailing List <linux-crypto@...r.kernel.org>,
David Miller <davem@...emloft.net>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH net-next v6 23/23] net: WireGuard secure network tunnel
On 26. 9. 2018 18:04, Jason A. Donenfeld wrote:
> Hi Ivan,
>
> On Wed, Sep 26, 2018 at 6:00 PM Ivan Labáth <labokml@...o.rs> wrote:
>>
>> On 25.09.2018 16:56, Jason A. Donenfeld wrote:
>>> Extensive documentation and description of the protocol and
>>> considerations, along with formal proofs of the cryptography, are> available at:
>>>
>>> * https://www.wireguard.com/
>>> * https://www.wireguard.com/papers/wireguard.pdf
>> []
>>> +enum { HANDSHAKE_DSCP = 0x88 /* AF41, plus 00 ECN */ };
>> []
>>> + if (skb->protocol == htons(ETH_P_IP)) {
>>> + len = ntohs(ip_hdr(skb)->tot_len);
>>> + if (unlikely(len < sizeof(struct iphdr)))
>>> + goto dishonest_packet_size;
>>> + if (INET_ECN_is_ce(PACKET_CB(skb)->ds))
>>> + IP_ECN_set_ce(ip_hdr(skb));
>>> + } else if (skb->protocol == htons(ETH_P_IPV6)) {
>>> + len = ntohs(ipv6_hdr(skb)->payload_len) +
>>> + sizeof(struct ipv6hdr);
>>> + if (INET_ECN_is_ce(PACKET_CB(skb)->ds))
>>> + IP6_ECN_set_ce(skb, ipv6_hdr(skb));
>>> + } else
>> []
>>> + skb_queue_walk (&packets, skb) {
>>> + /* 0 for no outer TOS: no leak. TODO: should we use flowi->tos
>>> + * as outer? */
>>> + PACKET_CB(skb)->ds = ip_tunnel_ecn_encap(0, ip_hdr(skb), skb);
>>> + PACKET_CB(skb)->nonce =
>>> + atomic64_inc_return(&key->counter.counter) - 1;
>>> + if (unlikely(PACKET_CB(skb)->nonce >= REJECT_AFTER_MESSAGES))
>>> + goto out_invalid;
>>> + }
>> Hi,
>>
>> is there documentation and/or rationale for ecn handling?
>> Quick search for ecn and dscp didn't reveal any.
>
> ECN support was developed with Dave Taht so that it does the right
> thing with CAKE and such. He's CC'd, so that he can fill in details,
> and sure, we can write these up. As well, I can add the rationale for
> the handshake-packet-specific DSCP value to the paper in the next few
> days; thanks for pointing out these documentation oversights.
>
> Jason
>
Any news on this?
To be clear, question is not about an insignificant documentation
oversight. It is about copying bits from inner packets to outer packets
of a secure* tunnel and documenting it AFAICT nowhere, while claiming
extensive documentation.
* it really should be specified what secure tunnel means, as it has many
plausible interpretations and wireguard surely does not fulfill all of them.
Ivan
Powered by blists - more mailing lists