From: Grigore Ion <ion.grig...@freescale.com>
This patch fixes the following problems:
- checksum computation for LE platforms
- checksum is computed in the CPU endianness. The returned result
must be converted to the BE ordering when it is used to update the
UDP checksum in a packet.
- checksum computation for packets having the UDP length not a
multiple of 2.
Signed-off-by: Grigore Ion <ion.grig...@freescale.com>
---
v1:
- Move variables declaration on top of block. (Maxim Uvarov)
- Check patch with checkpatch script. (Maxim Uvarov)
- L3 header presence is tested twice. (Alexandru Badicioiu)
- Remove unnecessary check for L3 header presence. (Bill Fischofer)
- Modify check of odp_packet_l4_offset() return. (Bill Fischofer)
helper/include/odp/helper/udp.h | 55 ++++++++++++++++----------------------
1 files changed, 23 insertions(+), 32 deletions(-)
diff --git a/helper/include/odp/helper/udp.h b/helper/include/odp/helper/udp.h
index 06c439b..99392c5 100644
--- a/helper/include/odp/helper/udp.h
+++ b/helper/include/odp/helper/udp.h
@@ -4,7 +4,6 @@
* SPDX-License-Identifier: BSD-3-Clause
*/
-
/**
* @file
*
@@ -22,7 +21,6 @@ extern "C" {
#include <odp/debug.h>
#include <odp/byteorder.h>
-
/** @addtogroup odph_header ODPH HEADER
* @{
*/
@@ -44,46 +42,39 @@ typedef struct ODP_PACKED {
* This function uses odp packet to calc checksum
*
* @param pkt calculate chksum for pkt
- * @return checksum value
+ * @return checksum value in CPU endianness
*/
static inline uint16_t odph_ipv4_udp_chksum(odp_packet_t pkt)
{
- uint32_t sum = 0;
- odph_udphdr_t *udph;
- odph_ipv4hdr_t *iph;
- uint16_t udplen;
- uint8_t *buf;
-
- if (!odp_packet_l3_offset(pkt))
- return 0;
+ odph_ipv4hdr_t *iph;
+ odph_udphdr_t *udph;
+ uint32_t sum;
+ uint16_t udplen, *buf;
- if (!odp_packet_l4_offset(pkt))
+ if (odp_packet_l4_offset(pkt) == ODP_PACKET_OFFSET_INVALID)
return 0;
-
iph = (odph_ipv4hdr_t *)odp_packet_l3_ptr(pkt, NULL);
udph = (odph_udphdr_t *)odp_packet_l4_ptr(pkt, NULL);
- udplen = odp_be_to_cpu_16(udph->length);
-
- /* 32-bit sum of all 16-bit words covered by UDP chksum */
+ /* 32-bit sum of UDP pseudo-header */
sum = (iph->src_addr & 0xFFFF) + (iph->src_addr >> 16) +
- (iph->dst_addr & 0xFFFF) + (iph->dst_addr >> 16) +
- (uint16_t)iph->proto + udplen;
- for (buf = (uint8_t *)udph; udplen > 1; udplen -= 2) {
- sum += ((*buf << 8) + *(buf + 1));
- buf += 2;
- }
-
- /* Fold sum to 16 bits: add carrier to result */
- while (sum >> 16)
- sum = (sum & 0xFFFF) + (sum >> 16);
-
+ (iph->dst_addr & 0xFFFF) + (iph->dst_addr >> 16) +
+ odp_be_to_cpu_16(iph->proto) + udph->length;
+ udplen = odp_be_to_cpu_16(udph->length);
+ buf = (uint16_t *)((void *)udph);
+ /* 32-bit sum of UDP header (checksum field cleared) and UDP data */
+ for ( ; udplen > 1; udplen -= 2)
+ sum += *buf++;
+ /* Length is not a multiple of 2 bytes */
+ if (udplen)
+ sum += odp_be_to_cpu_16(*((uint8_t *)buf) << 8);
+ /* Fold sum to 16 bits */
+ sum = (sum & 0xFFFF) + (sum >> 16);
+ /* Add carrier (0/1) to result */
+ sum += (sum >> 16);
/* 1's complement */
sum = ~sum;
-
- /* set computation result */
- sum = (sum == 0x0) ? 0xFFFF : sum;
-
- return sum;
+ /* Set computation result */
+ return (sum == 0x0) ? 0xFFFF : odp_be_to_cpu_16(sum);
}
/** @internal Compile time assert */
--
1.7.3.4
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