mir/ovs
2
0
Fork 0
mirror of https://github.com/openvswitch/ovs synced 2025-08-31 14:25:26 +00:00
Code Issues Releases Wiki Activity

flow: Add flow_compose_size().

Browse Source 
This allows to compose packets with different real lenghts from
odp flows i.e. memory will be allocated for requested packet
size and all required headers like ip->tot_len filled correctly.

Will be used in netdev-dummy to properly handle '--len' option.

Suggested-by: Andy Zhou <azhou@ovn.org>
Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Signed-off-by: Andy Zhou <azhou@ovn.org>
This commit is contained in:
Ilya Maximets
2017-07-25 16:02:00 +03:00
committed by Andy Zhou
parent fc17717869
commit 3476ce3ad7
2 changed files with 56 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

65
lib/flow.c
View File

@@ -2706,40 +2706,85 @@ flow_compose_l4_csum(struct dp_packet *p, const struct flow *flow,
if (flow->nw_proto == IPPROTO_TCP) {
struct tcp_header *tcp = dp_packet_l4(p);
/* Checksum has already been zeroed by put_zeros call in
* flow_compose_l4(). */
tcp->tcp_csum = 0;
tcp->tcp_csum = csum_finish(csum_continue(pseudo_hdr_csum,
tcp, l4_len));
} else if (flow->nw_proto == IPPROTO_UDP) {
struct udp_header *udp = dp_packet_l4(p);
/* Checksum has already been zeroed by put_zeros call in
* flow_compose_l4(). */
udp->udp_csum = 0;
udp->udp_csum = csum_finish(csum_continue(pseudo_hdr_csum,
udp, l4_len));
} else if (flow->nw_proto == IPPROTO_ICMP) {
struct icmp_header *icmp = dp_packet_l4(p);
/* Checksum has already been zeroed by put_zeros call in
* flow_compose_l4(). */
icmp->icmp_csum = 0;
icmp->icmp_csum = csum(icmp, l4_len);
} else if (flow->nw_proto == IPPROTO_IGMP) {
struct igmp_header *igmp = dp_packet_l4(p);
/* Checksum has already been zeroed by put_zeros call in
* flow_compose_l4(). */
igmp->igmp_csum = 0;
igmp->igmp_csum = csum(igmp, l4_len);
} else if (flow->nw_proto == IPPROTO_ICMPV6) {
struct icmp6_hdr *icmp = dp_packet_l4(p);
/* Checksum has already been zeroed by put_zeros call in
* flow_compose_l4(). */
icmp->icmp6_cksum = 0;
icmp->icmp6_cksum = (OVS_FORCE uint16_t)
csum_finish(csum_continue(pseudo_hdr_csum, icmp, l4_len));
}
}
}
/* Tries to increase the size of packet composed by 'flow_compose' up to
* 'size' bytes. Fixes all the required packet headers like ip/udp lengths
* and l3/l4 checksums. */
void
flow_compose_size(struct dp_packet *p, const struct flow *flow, size_t size)
{
size_t extra_size;
if (size <= dp_packet_size(p)) {
return;
}
extra_size = size - dp_packet_size(p);
dp_packet_put_zeros(p, extra_size);
if (flow->dl_type == htons(FLOW_DL_TYPE_NONE)) {
struct eth_header *eth = dp_packet_eth(p);
eth->eth_type = htons(dp_packet_size(p));
} else if (dl_type_is_ip_any(flow->dl_type)) {
uint32_t pseudo_hdr_csum;
size_t l4_len = (char *) dp_packet_tail(p) - (char *) dp_packet_l4(p);
if (flow->dl_type == htons(ETH_TYPE_IP)) {
struct ip_header *ip = dp_packet_l3(p);
ip->ip_tot_len = htons(p->l4_ofs - p->l3_ofs + l4_len);
ip->ip_csum = 0;
ip->ip_csum = csum(ip, sizeof *ip);
pseudo_hdr_csum = packet_csum_pseudoheader(ip);
} else { /* ETH_TYPE_IPV6 */
struct ovs_16aligned_ip6_hdr *nh = dp_packet_l3(p);
nh->ip6_plen = htons(l4_len);
pseudo_hdr_csum = packet_csum_pseudoheader6(nh);
}
if ((!(flow->nw_frag & FLOW_NW_FRAG_ANY)
|| !(flow->nw_frag & FLOW_NW_FRAG_LATER))
&& flow->nw_proto == IPPROTO_UDP) {
struct udp_header *udp = dp_packet_l4(p);
udp->udp_len = htons(l4_len + extra_size);
}
flow_compose_l4_csum(p, flow, pseudo_hdr_csum);
}
}
/* Puts into 'p' a packet that flow_extract() would parse as having the given
* 'flow'.
*