diff mbox series

lib/librte_net: fix bug for ipv4 checksum calculating

Message ID 20200509082421.24588-1-guohongzhi1@huawei.com (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series lib/librte_net: fix bug for ipv4 checksum calculating |

Checks

Context Check Description
ci/checkpatch warning coding style issues
ci/travis-robot success Travis build: passed
ci/Intel-compilation success Compilation OK
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-nxp-Performance success Performance Testing PASS
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-testing fail Testing issues

Commit Message

Hongzhi Guo May 9, 2020, 8:24 a.m. UTC 
  The function of rte_ipv4_cksum for calculating the checksum of IPv4 header is incorrect. This function will return checksum value like 0xffff. This value, however, is considered an illegal checksum on some switches(like Trident3).
RFC 1624 specifies the IPv4 checksum as follows:
https://tools.ietf.org/rfc/rfc1624
Since there is guaranteed to be at least one
   non-zero field in the IP header, and the checksum field in the
   protocol header is the complement of the sum, the checksum field can
   never contain ~(+0), which is -0 (0xFFFF).  It can, however, contain
   ~(-0), which is +0 (0x0000).
---
 lib/librte_net/rte_ip.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h
index 1ceb7b7..ece2e43 100644
--- a/lib/librte_net/rte_ip.h
+++ b/lib/librte_net/rte_ip.h
@@ -267,7 +267,7 @@  rte_ipv4_cksum(const struct rte_ipv4_hdr *ipv4_hdr)
 {
 	uint16_t cksum;
 	cksum = rte_raw_cksum(ipv4_hdr, sizeof(struct rte_ipv4_hdr));
-	return (cksum == 0xffff) ? cksum : (uint16_t)~cksum;
+	return (uint16_t)~cksum;
 }
 
 /**