DPDK patches and discussions
 help / color / mirror / Atom feed
* [dpdk-dev] [PATCH] net: calculate checksums for packets with IPv4 options
@ 2020-08-21 11:32 Michael Pfeiffer
  2020-08-29 11:43 ` Andrew Rybchenko
  2020-09-01  9:47 ` [dpdk-dev] [PATCH v2] " Michael Pfeiffer
  0 siblings, 2 replies; 9+ messages in thread
From: Michael Pfeiffer @ 2020-08-21 11:32 UTC (permalink / raw)
  To: Olivier Matz; +Cc: dev, Michael Pfeiffer

Currently, rte_ipv4_cksum() and rte_ipv4_udptcp_cksum() assume all IPv4
headers have sizeof(struct rte_ipv4_hdr) bytes. This is not true for
those (rare) packets with IPv4 options. Thus, both IPv4 and TCP/UDP
checksums are calculated wrong.

This patch fixes the issue by using the actual IPv4 header length from
the packet's IHL field.

Signed-off-by: Michael Pfeiffer <michael.pfeiffer@tu-ilmenau.de>
---
 lib/librte_net/rte_ip.h | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h
index fcd1eb342..6c3ff2603 100644
--- a/lib/librte_net/rte_ip.h
+++ b/lib/librte_net/rte_ip.h
@@ -269,7 +269,7 @@ static inline uint16_t
 rte_ipv4_cksum(const struct rte_ipv4_hdr *ipv4_hdr)
 {
 	uint16_t cksum;
-	cksum = rte_raw_cksum(ipv4_hdr, sizeof(struct rte_ipv4_hdr));
+	cksum = rte_raw_cksum(ipv4_hdr, (ipv4_hdr->version_ihl & 0xf) * 4);
 	return (uint16_t)~cksum;
 }
 
@@ -311,7 +311,7 @@ rte_ipv4_phdr_cksum(const struct rte_ipv4_hdr *ipv4_hdr, uint64_t ol_flags)
 	} else {
 		psd_hdr.len = rte_cpu_to_be_16(
 			(uint16_t)(rte_be_to_cpu_16(ipv4_hdr->total_length)
-				- sizeof(struct rte_ipv4_hdr)));
+				- ((ipv4_hdr->version_ihl & 0xf) * 4)));
 	}
 	return rte_raw_cksum(&psd_hdr, sizeof(psd_hdr));
 }
@@ -319,8 +319,8 @@ rte_ipv4_phdr_cksum(const struct rte_ipv4_hdr *ipv4_hdr, uint64_t ol_flags)
 /**
  * Process the IPv4 UDP or TCP checksum.
  *
- * The IPv4 header should not contains options. The IP and layer 4
- * checksum must be set to 0 in the packet by the caller.
+ * The IP and layer 4 checksum must be set to 0 in the packet by
+ * the caller.
  *
  * @param ipv4_hdr
  *   The pointer to the contiguous IPv4 header.
@@ -339,7 +339,7 @@ rte_ipv4_udptcp_cksum(const struct rte_ipv4_hdr *ipv4_hdr, const void *l4_hdr)
 	if (l3_len < sizeof(struct rte_ipv4_hdr))
 		return 0;
 
-	l4_len = l3_len - sizeof(struct rte_ipv4_hdr);
+	l4_len = l3_len - ((ipv4_hdr->version_ihl & 0xf) * 4);
 
 	cksum = rte_raw_cksum(l4_hdr, l4_len);
 	cksum += rte_ipv4_phdr_cksum(ipv4_hdr, 0);
-- 
2.28.0


^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2020-10-06 15:14 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-21 11:32 [dpdk-dev] [PATCH] net: calculate checksums for packets with IPv4 options Michael Pfeiffer
2020-08-29 11:43 ` Andrew Rybchenko
2020-09-01  9:47 ` [dpdk-dev] [PATCH v2] " Michael Pfeiffer
2020-09-07  7:48   ` Andrew Rybchenko
2020-10-05 22:55   ` Thomas Monjalon
2020-10-06  2:39     ` Stephen Hemminger
2020-10-06  8:10       ` Olivier Matz
2020-10-06  9:51         ` Michael Pfeiffer
2020-10-06 15:10         ` Thomas Monjalon

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).