static int parse_layer3_packet_by_proto(struct packet *packet,
u16 proto, u8 *header_start,
u8 *packet_end, char **error)
{
u8 *p = header_start;
if (proto == ETHERTYPE_IP) {
struct ipv4 *ip = NULL;
/* Examine IPv4 header. */
if (p + sizeof(struct ipv4) > packet_end) {
asprintf(error, "IPv4 header overflows packet");
goto error_out;
}
/* Look at the IP version number, which is in the first 4 bits
* of both IPv4 and IPv6 packets.
*/
ip = (struct ipv4 *)p;
if (ip->version == 4) {
return parse_ipv4(packet, p, packet_end, error);
} else {
asprintf(error, "Bad IP version for ETHERTYPE_IP");
goto error_out;
}
} else if (proto == ETHERTYPE_IPV6) {
struct ipv6 *ip = NULL;
/* Examine IPv6 header. */
if (p + sizeof(struct ipv6) > packet_end) {
asprintf(error, "IPv6 header overflows packet");
goto error_out;
}
/* Look at the IP version number, which is in the first 4 bits
* of both IPv4 and IPv6 packets.
*/
ip = (struct ipv6 *)p;
if (ip->version == 6) {
return parse_ipv6(packet, p, packet_end, error);
} else {
asprintf(error, "Bad IP version for ETHERTYPE_IPV6");
goto error_out;
}
} else if ((proto == ETHERTYPE_MPLS_UC) ||
(proto == ETHERTYPE_MPLS_MC)) {
return parse_mpls(packet, p, packet_end, error);
} else {
return PACKET_UNKNOWN_L4;
}
error_out:
return PACKET_BAD;
}
/* Initializes 'flow' members from 'packet', 'skb_priority', 'tnl', and
* 'ofp_in_port'.
*
* Initializes 'packet' header pointers as follows:
*
* - packet->l2 to the start of the Ethernet header.
*
* - packet->l2_5 to the start of the MPLS shim 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.
*/
void
flow_extract(struct ofpbuf *packet, uint32_t skb_priority, uint32_t skb_mark,
const struct flow_tnl *tnl, uint16_t ofp_in_port,
struct flow *flow)
{
struct ofpbuf b = *packet;
struct eth_header *eth;
COVERAGE_INC(flow_extract);
memset(flow, 0, sizeof *flow);
if (tnl) {
ovs_assert(tnl != &flow->tunnel);
flow->tunnel = *tnl;
}
flow->in_port = ofp_in_port;
flow->skb_priority = skb_priority;
flow->skb_mark = skb_mark;
packet->l2 = b.data;
packet->l2_5 = NULL;
packet->l3 = NULL;
packet->l4 = NULL;
packet->l7 = NULL;
if (b.size < sizeof *eth) {
return;
}
/* 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, vlan_tci. */
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);
/* Parse mpls, copy l3 ttl. */
if (eth_type_mpls(flow->dl_type)) {
packet->l2_5 = b.data;
parse_mpls(&b, flow);
}
packet->l3 = b.data;
flow_extract_l3_onwards(packet, flow, flow->dl_type);
}
/* Initializes 'flow' members from 'packet', 'skb_priority', 'tnl', and
* 'in_port'.
*
* Initializes 'packet' header pointers as follows:
*
* - packet->l2 to the start of the Ethernet header.
*
* - packet->l2_5 to the start of the MPLS shim 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/UDP/SCTP/ICMP header, if one is
* present and has a correct length, and otherwise NULL.
*/
void
flow_extract(struct ofpbuf *packet, uint32_t skb_priority, uint32_t pkt_mark,
const struct flow_tnl *tnl, const union flow_in_port *in_port,
struct flow *flow)
{
struct ofpbuf b = *packet;
struct eth_header *eth;
COVERAGE_INC(flow_extract);
memset(flow, 0, sizeof *flow);
if (tnl) {
ovs_assert(tnl != &flow->tunnel);
flow->tunnel = *tnl;
}
if (in_port) {
flow->in_port = *in_port;
}
flow->skb_priority = skb_priority;
flow->pkt_mark = pkt_mark;
packet->l2 = b.data;
packet->l2_5 = NULL;
packet->l3 = NULL;
packet->l4 = NULL;
packet->l7 = NULL;
if (b.size < sizeof *eth) {
return;
}
/* 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, vlan_tci. */
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);
/* Parse mpls, copy l3 ttl. */
if (eth_type_mpls(flow->dl_type)) {
packet->l2_5 = b.data;
parse_mpls(&b, flow);
}
/* Network layer. */
packet->l3 = b.data;
if (flow->dl_type == htons(ETH_TYPE_IP)) {
const struct ip_header *nh = pull_ip(&b);
if (nh) {
packet->l4 = b.data;
flow->nw_src = get_16aligned_be32(&nh->ip_src);
flow->nw_dst = get_16aligned_be32(&nh->ip_dst);
flow->nw_proto = nh->ip_proto;
flow->nw_tos = nh->ip_tos;
if (IP_IS_FRAGMENT(nh->ip_frag_off)) {
flow->nw_frag = FLOW_NW_FRAG_ANY;
if (nh->ip_frag_off & htons(IP_FRAG_OFF_MASK)) {
flow->nw_frag |= FLOW_NW_FRAG_LATER;
}
}
flow->nw_ttl = nh->ip_ttl;
if (!(nh->ip_frag_off & htons(IP_FRAG_OFF_MASK))) {
if (flow->nw_proto == IPPROTO_TCP) {
parse_tcp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_UDP) {
parse_udp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_SCTP) {
parse_sctp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_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 if (flow->dl_type == htons(ETH_TYPE_IPV6)) {
if (parse_ipv6(&b, flow)) {
return;
}
packet->l4 = b.data;
if (flow->nw_proto == IPPROTO_TCP) {
parse_tcp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_UDP) {
parse_udp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_SCTP) {
parse_sctp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_ICMPV6) {
if (parse_icmpv6(&b, flow)) {
packet->l7 = b.data;
}
}
} else if (flow->dl_type == htons(ETH_TYPE_ARP) ||
flow->dl_type == htons(ETH_TYPE_RARP)) {
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);
}
flow->nw_src = get_16aligned_be32(&arp->ar_spa);
flow->nw_dst = get_16aligned_be32(&arp->ar_tpa);
memcpy(flow->arp_sha, arp->ar_sha, ETH_ADDR_LEN);
memcpy(flow->arp_tha, arp->ar_tha, ETH_ADDR_LEN);
}
}
}
