net: checksum: Add IP header checksum calculation

At present net_checksum_calculate() only calculates TCP/UDP checksum
in an IP packet, but assumes the IP header checksum to be provided
by the software, e.g.: Linux kernel always calculates the IP header
checksum. However this might not always be the case, e.g.: for an IP
checksum offload enabled stack like VxWorks, the IP header checksum
can be zero.

This adds the checksum calculation of the IP header.

Signed-off-by: Guishan Qin <guishan.qin@windriver.com>
Signed-off-by: Yabing Liu <yabing.liu@windriver.com>
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This commit is contained in:
Guishan Qin 2020-12-11 17:35:11 +08:00 committed by Jason Wang
parent 0dcf0c0aee
commit d97f11590a

View File

@ -61,6 +61,7 @@ void net_checksum_calculate(uint8_t *data, int length)
{ {
int mac_hdr_len, ip_len; int mac_hdr_len, ip_len;
struct ip_header *ip; struct ip_header *ip;
uint16_t csum;
/* /*
* Note: We cannot assume "data" is aligned, so the all code uses * Note: We cannot assume "data" is aligned, so the all code uses
@ -106,6 +107,11 @@ void net_checksum_calculate(uint8_t *data, int length)
return; /* not IPv4 */ return; /* not IPv4 */
} }
/* Calculate IP checksum */
stw_he_p(&ip->ip_sum, 0);
csum = net_raw_checksum((uint8_t *)ip, IP_HDR_GET_LEN(ip));
stw_be_p(&ip->ip_sum, csum);
if (IP4_IS_FRAGMENT(ip)) { if (IP4_IS_FRAGMENT(ip)) {
return; /* a fragmented IP packet */ return; /* a fragmented IP packet */
} }
@ -122,7 +128,6 @@ void net_checksum_calculate(uint8_t *data, int length)
switch (ip->ip_p) { switch (ip->ip_p) {
case IP_PROTO_TCP: case IP_PROTO_TCP:
{ {
uint16_t csum;
tcp_header *tcp = (tcp_header *)(ip + 1); tcp_header *tcp = (tcp_header *)(ip + 1);
if (ip_len < sizeof(tcp_header)) { if (ip_len < sizeof(tcp_header)) {
@ -143,7 +148,6 @@ void net_checksum_calculate(uint8_t *data, int length)
} }
case IP_PROTO_UDP: case IP_PROTO_UDP:
{ {
uint16_t csum;
udp_header *udp = (udp_header *)(ip + 1); udp_header *udp = (udp_header *)(ip + 1);
if (ip_len < sizeof(udp_header)) { if (ip_len < sizeof(udp_header)) {