netdev - Re: [PATCH net-next v3] tls: Add opt-in zerocopy mode of sendfile()

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: <20220518214311.45be0bd9@kernel.org>
Date:   Wed, 18 May 2022 21:43:11 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Maxim Mikityanskiy <maximmi@...dia.com>
Cc:     "David S. Miller" <davem@...emloft.net>,
        Daniel Borkmann <daniel@...earbox.net>,
        Paolo Abeni <pabeni@...hat.com>,
        Boris Pismenny <borisp@...dia.com>,
        Tariq Toukan <tariqt@...dia.com>,
        "Saeed Mahameed" <saeedm@...dia.com>,
        Gal Pressman <gal@...dia.com>, <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next v3] tls: Add opt-in zerocopy mode of sendfile()

On Wed, 18 May 2022 12:27:31 +0300 Maxim Mikityanskiy wrote:
> TLS device offload copies sendfile data to a bounce buffer before
> transmitting. It allows to maintain the valid MAC on TLS records when
> the file contents change and a part of TLS record has to be
> retransmitted on TCP level.
> 
> In many common use cases (like serving static files over HTTPS) the file
> contents are not changed on the fly. In many use cases breaking the
> connection is totally acceptable if the file is changed during
> transmission, because it would be received corrupted in any case.
> 
> This commit allows to optimize performance for such use cases to
> providing a new optional mode of TLS sendfile(), in which the extra copy
> is skipped. Removing this copy improves performance significantly, as
> TLS and TCP sendfile perform the same operations, and the only overhead
> is TLS header/trailer insertion.

Reviewed-by: Jakub Kicinski <kuba@...nel.org>