示例#1
0
文件: flow.c 项目: Grace-Liu/dpdk-ovs
static void
parse_udp(struct ofpbuf *packet, struct ofpbuf *b, struct flow *flow)
{
    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;
    }
}
示例#2
0
文件: flow.c 项目: InCNTRE/OFTT
/* 'tun_id' is in network byte order, while 'in_port' is in host byte order.
 * These byte orders are the same as they are in struct odp_flow_key.
 *
 * Initializes packet header pointers as follows:
 *
 *    - packet->l2 to the start of the Ethernet header.
 *
 *    - packet->l3 to just past the Ethernet header, or just past the
 *      vlan_header if one is present, to the first byte of the payload of the
 *      Ethernet frame.
 *
 *    - packet->l4 to just past the IPv4 header, if one is present and has a
 *      correct length, and otherwise NULL.
 *
 *    - packet->l7 to just past the TCP or UDP or ICMP header, if one is
 *      present and has a correct length, and otherwise NULL.
 */
int
flow_extract(struct ofpbuf *packet, uint32_t tun_id, uint16_t in_port,
             flow_t *flow)
{
    struct ofpbuf b = *packet;
    struct eth_header *eth;
    int retval = 0;

    COVERAGE_INC(flow_extract);

    memset(flow, 0, sizeof *flow);
    flow->tun_id = tun_id;
    flow->in_port = in_port;
    flow->dl_vlan = htons(OFP_VLAN_NONE);

    packet->l2 = b.data;
    packet->l3 = NULL;
    packet->l4 = NULL;
    packet->l7 = NULL;

    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;
                    }
                }
            } else {
                retval = 1;
            }
        }
    } else if (flow->dl_type == htons(ETH_TYPE_ARP)) {
        const struct arp_eth_header *arp = pull_arp(&b);
        if (arp && arp->ar_hrd == htons(1)
            && arp->ar_pro == htons(ETH_TYPE_IP)
            && arp->ar_hln == ETH_ADDR_LEN
            && arp->ar_pln == 4) {
            /* We only match on the lower 8 bits of the opcode. */
            if (ntohs(arp->ar_op) <= 0xff) {
                flow->nw_proto = ntohs(arp->ar_op);
            }

            if ((flow->nw_proto == ARP_OP_REQUEST)
                || (flow->nw_proto == ARP_OP_REPLY)) {
                flow->nw_src = arp->ar_spa;
                flow->nw_dst = arp->ar_tpa;
            }
        }
    }
    return retval;
}
示例#3
0
/* Returns 1 if 'packet' is an IP fragment, 0 otherwise. */
int
flow_extract(struct ofpbuf *packet, uint32_t in_port, struct flow *flow)
{
    struct ofpbuf b = *packet;
    struct eth_header *eth;
    int retval = 0;

    memset(flow, 0, sizeof *flow);
    flow->dl_vlan = htons(OFPVID_NONE);
    flow->in_port = htonl(in_port);

    packet->l2 = b.data;
    packet->l3 = NULL;
    packet->l4 = NULL;
    packet->l7 = NULL;

    eth = pull_eth(&b);
    if (eth) {
        if (ntohs(eth->eth_type) >= 0x600) {
            /* 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);
            } else {
                flow->dl_type = htons(0x05ff);
                ofpbuf_pull(&b, sizeof(struct llc_header));
            }
        }

        /* Check for a VLAN tag */
        if (flow->dl_type == htons(ETH_TYPE_VLAN)) {
            struct vlan_header *vh = pull_vlan(&b);
            if (vh) {
                flow->dl_type = vh->vlan_next_type;
                flow->dl_vlan = vh->vlan_tci & htons(VLAN_VID_MASK);
                flow->dl_vlan_pcp = (uint8_t)((ntohs(vh->vlan_tci) >> VLAN_PCP_SHIFT)
                                               & VLAN_PCP_BITMASK);
            }
        }
        memcpy(flow->dl_src, eth->eth_src, ETH_ADDR_LEN);
        memcpy(flow->dl_dst, eth->eth_dst, ETH_ADDR_LEN);

        packet->l3 = b.data;
        if (flow->dl_type == htons(ETH_TYPE_IP)) {
            const struct ip_header *nh = pull_ip(&b);
            if (nh) {
                flow->nw_tos = nh->ip_tos & 0xfc;
                flow->nw_proto = nh->ip_proto;
                flow->nw_src = nh->ip_src;
                flow->nw_dst = nh->ip_dst;
                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 {
                            /* Avoid tricking other code into thinking that
                             * this packet has an L4 header. */
                            flow->nw_proto = 0;
                        }
                    } 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 {
                            /* Avoid tricking other code into thinking that
                             * this packet has an L4 header. */
                            flow->nw_proto = 0;
                        }
                    } else if (flow->nw_proto == IP_TYPE_ICMP) {
                        const struct icmp_header *icmp = pull_icmp(&b);
                        if (icmp) {
                            flow->tp_src = htons(icmp->icmp_type);
                            flow->tp_dst = htons(icmp->icmp_code);
                            packet->l7 = b.data;
                        } else {
                            /* Avoid tricking other code into thinking that
                             * this packet has an L4 header. */
                            flow->nw_proto = 0;
                        }
                    }
                } else {
                    retval = 1;
                }
            }
        } else if (flow->dl_type == htons(ETH_TYPE_ARP)) {
            struct arp_eth_header *arp = pull_arp(&b);
            if (arp) {
                if (arp->ar_pro == htons(ARP_PRO_IP) && arp->ar_pln == IP_ADDR_LEN) {
                    flow->nw_src = arp->ar_spa;
                    flow->nw_dst = arp->ar_tpa;
                }
                flow->nw_proto = ntohs(arp->ar_op) & 0xff;
            }
        }
    }
    return retval;
}