netdev - Re: [RFC PATCH net-next 2/2] udp: add sk opt to allow sending pkt with src 0.0.0.0

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:	Mon, 11 Nov 2013 00:18:03 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	nicolas.dichtel@...nd.com
Cc:	hannes@...essinduktion.org, netdev@...r.kernel.org,
	David.Laight@...LAB.COM, jiri@...nulli.us, vyasevich@...il.com,
	kuznet@....inr.ac.ru, jmorris@...ei.org, yoshfuji@...ux-ipv6.org,
	kaber@...sh.net, thaller@...hat.com, stephen@...workplumber.org
Subject: Re: [RFC PATCH net-next 2/2] udp: add sk opt to allow sending pkt
 with src 0.0.0.0

From: Nicolas Dichtel <nicolas.dichtel@...nd.com>
Date: Sat,  9 Nov 2013 01:54:34 +0100

> This feature allows to a send packets with address source set to 0.0.0.0 even if
> an ip address is available on another interface.
> 
> It's useful for DHCP client, to allow them to use UDP sockets and be compliant
> with the RFC2131, Section 4.1:
> 
> 4.1 Constructing and sending DHCP messages
> ...
>    DHCP messages broadcast by a client prior to that client obtaining
>    its IP address must have the source address field in the IP header
>    set to 0.
> 
> Based on a previous work from
> Guillaume Gaudonville <guillaume.gaudonville@...nd.com>.
> 
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@...nd.com>

This requirement of the RFC is inconsistent with a host based
addressing model, that which Linux employs, it assumes an interface
based one.

The wording here is also very ambiguous.

This RFC fails to even remotely consider what the right behavior
should be in a host based addressing environment at all, and anyone
reading this RFC should just accept that.

Furthermore, the fact that you're implementing _addressing_ policy in
the UDP code makes this change even more unreasonable.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html