DPDK patches and discussions
 help / color / mirror / Atom feed
From: guohongzhi <guohongzhi1@huawei.com>
To: <dev@dpdk.org>
Cc: <stable@dpdk.org>, <olivier.matz@6wind.com>,
	<mb@smartsharesystems.com>, <konstantin.ananyev@intel.com>,
	<jiayu.hu@intel.com>, <ferruh.yigit@intel.com>,
	<nicolas.chautru@intel.com>, <cristian.dumitrescu@intel.com>,
	<zhoujingbin@huawei.com>, <chenchanghu@huawei.com>,
	<jerry.lilijun@huawei.com>, <haifeng.lin@huawei.com>,
	<guohongzhi1@huawei.com>
Subject: [dpdk-dev] [PATCH] bugfix: udptcp_checksum should tread tcp and udp differently
Date: Wed, 27 May 2020 22:40:03 +0800
Message-ID: <20200527144003.3592-1-guohongzhi1@huawei.com> (raw)

RFC 768 for UDP specifies:
If the computed  checksum  is zero,  it is transmitted  as all ones.
An all zero transmitted checksum  value means that the transmitter
generated  no checksum.

RFC 793 for TCP has no such special treatment for the checksum of zero.

Signed-off-by: guohongzhi <guohongzhi1@huawei.com>
---
 lib/librte_net/rte_ip.h | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h
index 1ceb7b7..8bef313 100644
--- a/lib/librte_net/rte_ip.h
+++ b/lib/librte_net/rte_ip.h
@@ -324,8 +324,7 @@ rte_ipv4_phdr_cksum(const struct rte_ipv4_hdr *ipv4_hdr, uint64_t ol_flags)
  * @param l4_hdr
  *   The pointer to the beginning of the L4 header.
  * @return
- *   The complemented checksum to set in the IP packet
- *   or 0 on error
+ *   The complemented checksum to set in the IP packet.
  */
 static inline uint16_t
 rte_ipv4_udptcp_cksum(const struct rte_ipv4_hdr *ipv4_hdr, const void *l4_hdr)
@@ -344,7 +343,10 @@ rte_ipv4_udptcp_cksum(const struct rte_ipv4_hdr *ipv4_hdr, const void *l4_hdr)
 
 	cksum = ((cksum & 0xffff0000) >> 16) + (cksum & 0xffff);
 	cksum = (~cksum) & 0xffff;
-	if (cksum == 0)
+	/* For Udp, if the computed checksum is zero,
+	 * it is transmitted as all ones.RFC768
+	 */
+	if (cksum == 0 && ipv4_hdr->next_proto_id == IPPROTO_UDP)
 		cksum = 0xffff;
 
 	return (uint16_t)cksum;
@@ -436,7 +438,10 @@ rte_ipv6_udptcp_cksum(const struct rte_ipv6_hdr *ipv6_hdr, const void *l4_hdr)
 
 	cksum = ((cksum & 0xffff0000) >> 16) + (cksum & 0xffff);
 	cksum = (~cksum) & 0xffff;
-	if (cksum == 0)
+	/* For Udp, if the computed checksum is zero,
+	 * it is transmitted as all ones.RFC768
+	 */
+	if (cksum == 0 && ipv6_hdr->proto == IPPROTO_UDP)
 		cksum = 0xffff;
 
 	return (uint16_t)cksum;
-- 
2.21.0.windows.1



             reply	other threads:[~2020-05-27 14:40 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-27 14:40 guohongzhi [this message]
2020-05-27 14:41 guohongzhi
2020-05-27 15:02 ` Stephen Hemminger
2020-05-27 15:36   ` Morten Brørup
2020-07-06  7:58     ` Olivier Matz

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=20200527144003.3592-1-guohongzhi1@huawei.com \
    --to=guohongzhi1@huawei.com \
    --cc=chenchanghu@huawei.com \
    --cc=cristian.dumitrescu@intel.com \
    --cc=dev@dpdk.org \
    --cc=ferruh.yigit@intel.com \
    --cc=haifeng.lin@huawei.com \
    --cc=jerry.lilijun@huawei.com \
    --cc=jiayu.hu@intel.com \
    --cc=konstantin.ananyev@intel.com \
    --cc=mb@smartsharesystems.com \
    --cc=nicolas.chautru@intel.com \
    --cc=olivier.matz@6wind.com \
    --cc=stable@dpdk.org \
    --cc=zhoujingbin@huawei.com \
    /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

DPDK patches and discussions

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ https://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev

Example config snippet for mirrors.
Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git