linux-sctp.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Xin Long <lucien.xin@gmail.com>
To: network dev <netdev@vger.kernel.org>, linux-sctp@vger.kernel.org
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
	Neil Horman <nhorman@tuxdriver.com>,
	Michael Tuexen <tuexen@fh-muenster.de>,
	davem@davemloft.net, Jakub Kicinski <kuba@kernel.org>,
	gnault@redhat.com, pabeni@redhat.com,
	willemdebruijn.kernel@gmail.com
Subject: [PATCHv5 net-next 03/16] udp: support sctp over udp in skb_udp_tunnel_segment
Date: Thu, 29 Oct 2020 15:04:57 +0800	[thread overview]
Message-ID: <e7575f9fea2b867bf0c7c3e8541e8a6101610055.1603955040.git.lucien.xin@gmail.com> (raw)
In-Reply-To: <4f439ed717442a649ba78dc0efc6f121208a9995.1603955040.git.lucien.xin@gmail.com>
In-Reply-To: <cover.1603955040.git.lucien.xin@gmail.com>

For the gso of sctp over udp packets, sctp_gso_segment() will be called in
skb_udp_tunnel_segment(), we need to set transport_header to sctp header.

As all the current HWs can't handle both crc checksum and udp checksum at
the same time, the crc checksum has to be done in sctp_gso_segment() by
removing the NETIF_F_SCTP_CRC flag from the features.

Meanwhile, if the HW can't do udp checksum, csum and csum_start has to be
set correctly, and udp checksum will be done in __skb_udp_tunnel_segment()
by calling gso_make_checksum().

Thanks to Paolo, Marcelo and Guillaume for helping with this one.

v1->v2:
  - no change.
v2->v3:
  - remove the he NETIF_F_SCTP_CRC flag from the features.
  - set csum and csum_start in sctp_gso_make_checksum().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 net/ipv4/udp_offload.c | 3 +++
 net/sctp/offload.c     | 6 +++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index e67a66f..b8b1fde 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -49,6 +49,7 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
 	__skb_pull(skb, tnl_hlen);
 	skb_reset_mac_header(skb);
 	skb_set_network_header(skb, skb_inner_network_offset(skb));
+	skb_set_transport_header(skb, skb_inner_transport_offset(skb));
 	skb->mac_len = skb_inner_network_offset(skb);
 	skb->protocol = new_protocol;
 
@@ -67,6 +68,8 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
 				      (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM))));
 
 	features &= skb->dev->hw_enc_features;
+	/* CRC checksum can't be handled by HW when it's a UDP tunneling packet. */
+	features &= ~NETIF_F_SCTP_CRC;
 
 	/* The only checksum offload we care about from here on out is the
 	 * outer one so strip the existing checksum feature flags and
diff --git a/net/sctp/offload.c b/net/sctp/offload.c
index 74847d6..ce281a9 100644
--- a/net/sctp/offload.c
+++ b/net/sctp/offload.c
@@ -27,7 +27,11 @@ static __le32 sctp_gso_make_checksum(struct sk_buff *skb)
 {
 	skb->ip_summed = CHECKSUM_NONE;
 	skb->csum_not_inet = 0;
-	gso_reset_checksum(skb, ~0);
+	/* csum and csum_start in GSO CB may be needed to do the UDP
+	 * checksum when it's a UDP tunneling packet.
+	 */
+	SKB_GSO_CB(skb)->csum = (__force __wsum)~0;
+	SKB_GSO_CB(skb)->csum_start = skb_headroom(skb) + skb->len;
 	return sctp_compute_cksum(skb, skb_transport_offset(skb));
 }
 
-- 
2.1.0


  reply	other threads:[~2020-10-29  7:23 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-29  7:04 [PATCHv5 net-next 00/16] sctp: Implement RFC6951: UDP Encapsulation of SCTP Xin Long
2020-10-29  7:04 ` [PATCHv5 net-next 01/16] udp: check udp sock encap_type in __udp_lib_err Xin Long
2020-10-29  7:04   ` [PATCHv5 net-next 02/16] udp6: move the mss check after udp gso tunnel processing Xin Long
2020-10-29  7:04     ` Xin Long [this message]
2020-10-29  7:04       ` [PATCHv5 net-next 04/16] sctp: create udp4 sock and add its encap_rcv Xin Long
2020-10-29  7:04         ` [PATCHv5 net-next 05/16] sctp: create udp6 sock and set " Xin Long
2020-10-29  7:05           ` [PATCHv5 net-next 06/16] sctp: add encap_err_lookup for udp encap socks Xin Long
2020-10-29  7:05             ` [PATCHv5 net-next 07/16] sctp: add encap_port for netns sock asoc and transport Xin Long
2020-10-29  7:05               ` [PATCHv5 net-next 08/16] sctp: add SCTP_REMOTE_UDP_ENCAPS_PORT sockopt Xin Long
2020-10-29  7:05                 ` [PATCHv5 net-next 09/16] sctp: allow changing transport encap_port by peer packets Xin Long
2020-10-29  7:05                   ` [PATCHv5 net-next 10/16] sctp: add udphdr to overhead when udp_port is set Xin Long
2020-10-29  7:05                     ` [PATCHv5 net-next 11/16] sctp: call sk_setup_caps in sctp_packet_transmit instead Xin Long
2020-10-29  7:05                       ` [PATCHv5 net-next 12/16] sctp: support for sending packet over udp4 sock Xin Long
2020-10-29  7:05                         ` [PATCHv5 net-next 13/16] sctp: support for sending packet over udp6 sock Xin Long
2020-10-29  7:05                           ` [PATCHv5 net-next 14/16] sctp: add the error cause for new encapsulation port restart Xin Long
2020-10-29  7:05                             ` [PATCHv5 net-next 15/16] sctp: handle the init chunk matching an existing asoc Xin Long
2020-10-29  7:05                               ` [PATCHv5 net-next 16/16] sctp: enable udp tunneling socks Xin Long
2020-10-29 21:55 ` [PATCHv5 net-next 00/16] sctp: Implement RFC6951: UDP Encapsulation of SCTP Marcelo Ricardo Leitner
2020-10-30 23:46 ` Jakub Kicinski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=e7575f9fea2b867bf0c7c3e8541e8a6101610055.1603955040.git.lucien.xin@gmail.com \
    --to=lucien.xin@gmail.com \
    --cc=davem@davemloft.net \
    --cc=gnault@redhat.com \
    --cc=kuba@kernel.org \
    --cc=linux-sctp@vger.kernel.org \
    --cc=marcelo.leitner@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=nhorman@tuxdriver.com \
    --cc=pabeni@redhat.com \
    --cc=tuexen@fh-muenster.de \
    --cc=willemdebruijn.kernel@gmail.com \
    --subject='Re: [PATCHv5 net-next 03/16] udp: support sctp over udp in skb_udp_tunnel_segment' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).