From: Eric Dumazet <edumazet@google.com>
To: Martin KaFai Lau <kafai@fb.com>
Cc: bpf <bpf@vger.kernel.org>, Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
kernel-team <kernel-team@fb.com>, Lawrence Brakmo <brakmo@fb.com>,
Neal Cardwell <ncardwell@google.com>,
netdev <netdev@vger.kernel.org>,
Yuchung Cheng <ycheng@google.com>
Subject: Re: [PATCH v3 bpf-next 4/9] tcp: Add unknown_opt arg to tcp_parse_options
Date: Fri, 31 Jul 2020 09:12:10 -0700 [thread overview]
Message-ID: <CANn89i+f4se896OPGx6dPKZuObeJR2gaTExqoAHmDK=r7cTmaw@mail.gmail.com> (raw)
In-Reply-To: <20200730205723.3353838-1-kafai@fb.com>
On Thu, Jul 30, 2020 at 1:58 PM Martin KaFai Lau <kafai@fb.com> wrote:
>
> In the latter patch, the bpf prog only wants to be called to handle
> a header option if that particular header option cannot be handled by
> the kernel. This unknown option could be written by the peer's bpf-prog.
> It could also be a new standard option that the running kernel does not
> support it while a bpf-prog can handle it.
>
> In a latter patch, the bpf prog will be called from tcp_validate_incoming()
> if there is unknown option and a flag is set in tp->bpf_sock_ops_cb_flags.
>
> Instead of using skb->cb[] in an earlier attempt, this patch
> adds an optional arg "bool *unknown_opt" to tcp_parse_options().
> The bool will be set to true if it has encountered an option
> that the kernel does not recognize.
>
> Signed-off-by: Martin KaFai Lau <kafai@fb.com>
> ---
> drivers/infiniband/hw/cxgb4/cm.c | 2 +-
> include/net/tcp.h | 3 ++-
> net/ipv4/syncookies.c | 2 +-
> net/ipv4/tcp_input.c | 40 +++++++++++++++++++++-----------
> net/ipv4/tcp_minisocks.c | 4 ++--
> net/ipv6/syncookies.c | 2 +-
> 6 files changed, 34 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
> index 30e08bcc9afb..dedca6576bb9 100644
> --- a/drivers/infiniband/hw/cxgb4/cm.c
> +++ b/drivers/infiniband/hw/cxgb4/cm.c
> @@ -3949,7 +3949,7 @@ static void build_cpl_pass_accept_req(struct sk_buff *skb, int stid , u8 tos)
> */
> memset(&tmp_opt, 0, sizeof(tmp_opt));
> tcp_clear_options(&tmp_opt);
> - tcp_parse_options(&init_net, skb, &tmp_opt, 0, NULL);
> + tcp_parse_options(&init_net, skb, &tmp_opt, 0, NULL, NULL);
>
> req = __skb_push(skb, sizeof(*req));
> memset(req, 0, sizeof(*req));
> diff --git a/include/net/tcp.h b/include/net/tcp.h
> index 895e7aabf136..d49d8f1c961a 100644
> --- a/include/net/tcp.h
> +++ b/include/net/tcp.h
> @@ -413,7 +413,8 @@ int tcp_mmap(struct file *file, struct socket *sock,
> #endif
> void tcp_parse_options(const struct net *net, const struct sk_buff *skb,
> struct tcp_options_received *opt_rx,
> - int estab, struct tcp_fastopen_cookie *foc);
> + int estab, struct tcp_fastopen_cookie *foc,
> + bool *unknown_opt);
> const u8 *tcp_parse_md5sig_option(const struct tcphdr *th);
>
Instead of changing signatures of many functions (and make future
stable backports challenging)
how about adding a field into 'struct tcp_options_received' ?
Sorry for not suggesting this earlier :/
next prev parent reply other threads:[~2020-07-31 16:12 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-30 20:56 [PATCH v3 bpf-next 0/9] BPF TCP header options Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 1/9] tcp: Use a struct to represent a saved_syn Martin KaFai Lau
2020-07-31 15:57 ` Eric Dumazet
2020-07-31 17:31 ` Eric Dumazet
2020-07-30 20:57 ` [PATCH v3 bpf-next 2/9] tcp: bpf: Add TCP_BPF_DELACK_MAX setsockopt Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 3/9] tcp: bpf: Add TCP_BPF_RTO_MIN for bpf_setsockopt Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 4/9] tcp: Add unknown_opt arg to tcp_parse_options Martin KaFai Lau
2020-07-31 16:12 ` Eric Dumazet [this message]
2020-07-31 17:37 ` Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 5/9] bpf: sock_ops: Change some members of sock_ops_kern from u32 to u8 Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 6/9] bpf: tcp: Allow bpf prog to write and parse TCP header option Martin KaFai Lau
2020-07-31 16:06 ` Eric Dumazet
2020-07-31 17:59 ` Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 7/9] bpf: selftests: Add fastopen_connect to network_helpers Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 8/9] bpf: selftests: tcp header options Martin KaFai Lau
2020-07-30 20:57 ` [PATCH v3 bpf-next 9/9] tcp: bpf: Optionally store mac header in TCP_SAVE_SYN Martin KaFai Lau
2020-07-31 15:51 ` Eric Dumazet
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