- eth = pull_eth(&b);
- if (eth) {
- if (ntohs(eth->eth_type) >= OFP_DL_TYPE_ETH2_CUTOFF) {
- /* This is an Ethernet II frame */
- flow->dl_type = eth->eth_type;
- } else {
- /* This is an 802.2 frame */
- struct llc_header *llc = ofpbuf_at(&b, 0, sizeof *llc);
- struct snap_header *snap = ofpbuf_at(&b, sizeof *llc,
- sizeof *snap);
- if (llc == NULL) {
- return 0;
- }
- if (snap
- && llc->llc_dsap == LLC_DSAP_SNAP
- && llc->llc_ssap == LLC_SSAP_SNAP
- && llc->llc_cntl == LLC_CNTL_SNAP
- && !memcmp(snap->snap_org, SNAP_ORG_ETHERNET,
- sizeof snap->snap_org)) {
- flow->dl_type = snap->snap_type;
- ofpbuf_pull(&b, LLC_SNAP_HEADER_LEN);
+ if (b.size < sizeof *eth) {
+ return 0;
+ }
+
+ /* Link layer. */
+ eth = b.data;
+ memcpy(flow->dl_src, eth->eth_src, ETH_ADDR_LEN);
+ memcpy(flow->dl_dst, eth->eth_dst, ETH_ADDR_LEN);
+
+ /* dl_type, dl_vlan, dl_vlan_pcp. */
+ ofpbuf_pull(&b, ETH_ADDR_LEN * 2);
+ if (eth->eth_type == htons(ETH_TYPE_VLAN)) {
+ parse_vlan(&b, flow);
+ }
+ flow->dl_type = parse_ethertype(&b);
+
+ /* Network layer. */
+ packet->l3 = b.data;
+ if (flow->dl_type == htons(ETH_TYPE_IP)) {
+ const struct ip_header *nh = pull_ip(&b);
+ if (nh) {
+ flow->nw_src = get_unaligned_u32(&nh->ip_src);
+ flow->nw_dst = get_unaligned_u32(&nh->ip_dst);
+ flow->nw_tos = nh->ip_tos & IP_DSCP_MASK;
+ flow->nw_proto = nh->ip_proto;
+ packet->l4 = b.data;
+ if (!IP_IS_FRAGMENT(nh->ip_frag_off)) {
+ if (flow->nw_proto == IP_TYPE_TCP) {
+ const struct tcp_header *tcp = pull_tcp(&b);
+ if (tcp) {
+ flow->tp_src = tcp->tcp_src;
+ flow->tp_dst = tcp->tcp_dst;
+ packet->l7 = b.data;
+ }
+ } else if (flow->nw_proto == IP_TYPE_UDP) {
+ const struct udp_header *udp = pull_udp(&b);
+ if (udp) {
+ flow->tp_src = udp->udp_src;
+ flow->tp_dst = udp->udp_dst;
+ packet->l7 = b.data;
+ }
+ } else if (flow->nw_proto == IP_TYPE_ICMP) {
+ const struct icmp_header *icmp = pull_icmp(&b);
+ if (icmp) {
+ flow->icmp_type = htons(icmp->icmp_type);
+ flow->icmp_code = htons(icmp->icmp_code);
+ packet->l7 = b.data;
+ }
+ }