netdev - Re: [PATCH net-next 00/12] Unmask upper DSCP bits

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]

Message-ID: <2a382dbb-0f90-4e6b-b8b9-844d93af5edc@kernel.org>
Date: Wed, 21 Aug 2024 11:00:51 -0600
From: David Ahern <dsahern@...nel.org>
To: Ido Schimmel <idosch@...dia.com>, netdev@...r.kernel.org
Cc: davem@...emloft.net, kuba@...nel.org, pabeni@...hat.com,
 edumazet@...gle.com, gnault@...hat.com, fw@...len.de, martin.lau@...ux.dev,
 daniel@...earbox.net, john.fastabend@...il.com, ast@...nel.org,
 pablo@...filter.org, kadlec@...filter.org, willemdebruijn.kernel@...il.com,
 bpf@...r.kernel.org, netfilter-devel@...r.kernel.org, coreteam@...filter.org
Subject: Re: [PATCH net-next 00/12] Unmask upper DSCP bits - part 1

On 8/21/24 6:52 AM, Ido Schimmel wrote:
> tl;dr - This patchset starts to unmask the upper DSCP bits in the IPv4
> flow key in preparation for allowing IPv4 FIB rules to match on DSCP. No
> functional changes are expected.
> 
> The TOS field in the IPv4 flow key ('flowi4_tos') is used during FIB
> lookup to match against the TOS selector in FIB rules and routes.
> 
> It is currently impossible for user space to configure FIB rules that
> match on the DSCP value as the upper DSCP bits are either masked in the
> various call sites that initialize the IPv4 flow key or along the path
> to the FIB core.
> 
> In preparation for adding a DSCP selector to IPv4 and IPv6 FIB rules, we
> need to make sure the entire DSCP value is present in the IPv4 flow key.
> This patchset starts to unmask the upper DSCP bits in the various places
> that invoke the core FIB lookup functions directly (patches #1-#7) and
> in the input route path (patches #8-#12). Future patchsets will do the
> same in the output route path.
> 
> No functional changes are expected as commit 1fa3314c14c6 ("ipv4:
> Centralize TOS matching") moved the masking of the upper DSCP bits to
> the core where 'flowi4_tos' is matched against the TOS selector.
> 

for the set:
Reviewed-by: David Ahern <dsahern@...nel.org>