+/*
+ * Parse a GTP protocol header.
+ * No optional fields and next extension header type.
+ */
+static void
+parse_gtp(struct rte_udp_hdr *udp_hdr,
+ struct testpmd_offload_info *info)
+{
+ struct rte_ipv4_hdr *ipv4_hdr;
+ struct rte_ipv6_hdr *ipv6_hdr;
+ struct rte_gtp_hdr *gtp_hdr;
+ uint8_t gtp_len = sizeof(*gtp_hdr);
+ uint8_t ip_ver;
+
+ /* Check udp destination port. */
+ if (udp_hdr->dst_port != _htons(RTE_GTPC_UDP_PORT) &&
+ udp_hdr->src_port != _htons(RTE_GTPC_UDP_PORT) &&
+ udp_hdr->dst_port != _htons(RTE_GTPU_UDP_PORT))
+ return;
+
+ info->is_tunnel = 1;
+ info->outer_ethertype = info->ethertype;
+ info->outer_l2_len = info->l2_len;
+ info->outer_l3_len = info->l3_len;
+ info->outer_l4_proto = info->l4_proto;
+ info->l2_len = 0;
+
+ gtp_hdr = (struct rte_gtp_hdr *)((char *)udp_hdr +
+ sizeof(struct rte_udp_hdr));
+
+ /*
+ * Check message type. If message type is 0xff, it is
+ * a GTP data packet. If not, it is a GTP control packet
+ */
+ if (gtp_hdr->msg_type == 0xff) {
+ ip_ver = *(uint8_t *)((char *)udp_hdr +
+ sizeof(struct rte_udp_hdr) +
+ sizeof(struct rte_gtp_hdr));
+ ip_ver = (ip_ver) & 0xf0;
+
+ if (ip_ver == RTE_GTP_TYPE_IPV4) {
+ ipv4_hdr = (struct rte_ipv4_hdr *)((char *)gtp_hdr +
+ gtp_len);
+ info->ethertype = _htons(RTE_ETHER_TYPE_IPV4);
+ parse_ipv4(ipv4_hdr, info);
+ } else if (ip_ver == RTE_GTP_TYPE_IPV6) {
+ ipv6_hdr = (struct rte_ipv6_hdr *)((char *)gtp_hdr +
+ gtp_len);
+ info->ethertype = _htons(RTE_ETHER_TYPE_IPV6);
+ parse_ipv6(ipv6_hdr, info);
+ }
+ } else {
+ info->ethertype = 0;
+ info->l4_len = 0;
+ info->l3_len = 0;
+ info->l4_proto = 0;
+ }
+
+ info->l2_len += RTE_ETHER_GTP_HLEN;
+}
+