+/* Session keys match the packets received, and mirror the packets sent */
+static u32
+acl_make_5tuple_session_key (acl_main_t * am, int is_input, int is_ip6,
+ u32 sw_if_index, fa_5tuple_t * p5tuple_pkt,
+ fa_5tuple_t * p5tuple_sess)
+{
+ int src_index = is_input ? 0 : 1;
+ int dst_index = is_input ? 1 : 0;
+ u32 valid_new_sess = 1;
+ p5tuple_sess->addr[src_index] = p5tuple_pkt->addr[0];
+ p5tuple_sess->addr[dst_index] = p5tuple_pkt->addr[1];
+ p5tuple_sess->l4.as_u64 = p5tuple_pkt->l4.as_u64;
+
+ if (PREDICT_TRUE(p5tuple_pkt->l4.proto != icmp_protos[is_ip6]))
+ {
+ p5tuple_sess->l4.port[src_index] = p5tuple_pkt->l4.port[0];
+ p5tuple_sess->l4.port[dst_index] = p5tuple_pkt->l4.port[1];
+ }
+ else
+ {
+ static const u8 * icmp_invmap[] = { icmp4_invmap, icmp6_invmap };
+ static const u8 * icmp_valid_new[] = { icmp4_valid_new, icmp6_valid_new };
+ static const u8 icmp_invmap_size[] = { sizeof(icmp4_invmap),
+ sizeof(icmp6_invmap) };
+ static const u8 icmp_valid_new_size[] = { sizeof(icmp4_valid_new),
+ sizeof(icmp6_valid_new) };
+ int type = is_ip6 ? p5tuple_pkt->l4.port[0]-128: p5tuple_pkt->l4.port[0];
+
+ p5tuple_sess->l4.port[0] = p5tuple_pkt->l4.port[0];
+ p5tuple_sess->l4.port[1] = p5tuple_pkt->l4.port[1];
+
+ /*
+ * Invert ICMP type for valid icmp_invmap messages:
+ * 1) input node with outbound ACL interface
+ * 2) output node with inbound ACL interface
+ *
+ */
+ if ((is_input && acl_fa_ifc_has_out_acl(am, sw_if_index)) ||
+ (!is_input && acl_fa_ifc_has_in_acl(am, sw_if_index)))
+ {
+ if (type >= 0 &&
+ type <= icmp_invmap_size[is_ip6] &&
+ icmp_invmap[is_ip6][type])
+ {
+ p5tuple_sess->l4.port[0] = icmp_invmap[is_ip6][type] - 1;
+ }
+ }
+
+ /*
+ * ONLY ICMP messages defined in icmp4_valid_new/icmp6_valid_new table
+ * are allowed to create stateful ACL.
+ * The other messages will be forwarded without creating a reflexive ACL.
+ */
+ if (type < 0 ||
+ type > icmp_valid_new_size[is_ip6] ||
+ !icmp_valid_new[is_ip6][type])
+ {
+ valid_new_sess = 0;
+ }
+ }
+
+ return valid_new_sess;
+}
+