+/**
+ * Get address and port values to be used for packet SNAT translation
+ * and create session if needed
+ *
+ * @param[in,out] sm SNAT main
+ * @param[in,out] node SNAT node runtime
+ * @param[in] thread_index thread index
+ * @param[in,out] b0 buffer containing packet to be translated
+ * @param[out] p_proto protocol used for matching
+ * @param[out] p_value address and port after NAT translation
+ * @param[out] p_dont_translate if packet should not be translated
+ * @param d optional parameter
+ * @param e optional parameter
+ */
+u32 icmp_match_in2out_det(snat_main_t *sm, vlib_node_runtime_t *node,
+ u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+ snat_session_key_t *p_value,
+ u8 *p_dont_translate, void *d, void *e)
+{
+ ip4_header_t *ip0;
+ icmp46_header_t *icmp0;
+ u32 sw_if_index0;
+ u32 rx_fib_index0;
+ u8 protocol;
+ snat_det_out_key_t key0;
+ u8 dont_translate = 0;
+ u32 next0 = ~0;
+ icmp_echo_header_t *echo0, *inner_echo0 = 0;
+ ip4_header_t *inner_ip0;
+ void *l4_header = 0;
+ icmp46_header_t *inner_icmp0;
+ snat_det_map_t * dm0 = 0;
+ ip4_address_t new_addr0;
+ u16 lo_port0, i0;
+ snat_det_session_t * ses0 = 0;
+ ip4_address_t in_addr;
+ u16 in_port;
+
+ ip0 = vlib_buffer_get_current (b0);
+ icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
+ echo0 = (icmp_echo_header_t *)(icmp0+1);
+ sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
+ rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
+
+ if (!icmp_is_error_message (icmp0))
+ {
+ protocol = SNAT_PROTOCOL_ICMP;
+ in_addr = ip0->src_address;
+ in_port = echo0->identifier;
+ }
+ else
+ {
+ inner_ip0 = (ip4_header_t *)(echo0+1);
+ l4_header = ip4_next_header (inner_ip0);
+ protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+ in_addr = inner_ip0->dst_address;
+ switch (protocol)
+ {
+ case SNAT_PROTOCOL_ICMP:
+ inner_icmp0 = (icmp46_header_t*)l4_header;
+ inner_echo0 = (icmp_echo_header_t *)(inner_icmp0+1);
+ in_port = inner_echo0->identifier;
+ break;
+ case SNAT_PROTOCOL_UDP:
+ case SNAT_PROTOCOL_TCP:
+ in_port = ((tcp_udp_header_t*)l4_header)->dst_port;
+ break;
+ default:
+ b0->error = node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
+ next0 = SNAT_IN2OUT_NEXT_DROP;
+ goto out;
+ }
+ }
+
+ dm0 = snat_det_map_by_user(sm, &in_addr);
+ if (PREDICT_FALSE(!dm0))
+ {
+ clib_warning("no match for internal host %U",
+ format_ip4_address, &in_addr);
+ if (PREDICT_FALSE(snat_not_translate_fast(sm, node, sw_if_index0, ip0,
+ IP_PROTOCOL_ICMP, rx_fib_index0)))
+ {
+ dont_translate = 1;
+ goto out;
+ }
+ next0 = SNAT_IN2OUT_NEXT_DROP;
+ b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
+ goto out;
+ }
+
+ snat_det_forward(dm0, &in_addr, &new_addr0, &lo_port0);
+
+ key0.ext_host_addr = ip0->dst_address;
+ key0.ext_host_port = 0;
+
+ ses0 = snat_det_find_ses_by_in(dm0, &in_addr, in_port, key0);
+ if (PREDICT_FALSE(!ses0))
+ {
+ if (PREDICT_FALSE(snat_not_translate_fast(sm, node, sw_if_index0, ip0,
+ IP_PROTOCOL_ICMP, rx_fib_index0)))
+ {
+ dont_translate = 1;
+ goto out;
+ }
+ if (icmp0->type != ICMP4_echo_request)
+ {
+ b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
+ next0 = SNAT_IN2OUT_NEXT_DROP;
+ goto out;
+ }
+ for (i0 = 0; i0 < dm0->ports_per_host; i0++)
+ {
+ key0.out_port = clib_host_to_net_u16 (lo_port0 +
+ ((i0 + clib_net_to_host_u16 (echo0->identifier)) % dm0->ports_per_host));
+
+ if (snat_det_get_ses_by_out (dm0, &in_addr, key0.as_u64))
+ continue;
+
+ ses0 = snat_det_ses_create(dm0, &in_addr, echo0->identifier, &key0);
+ break;
+ }
+ if (PREDICT_FALSE(!ses0))
+ {
+ next0 = SNAT_IN2OUT_NEXT_DROP;
+ b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
+ goto out;
+ }
+ }
+
+ if (PREDICT_FALSE(icmp0->type != ICMP4_echo_request &&
+ !icmp_is_error_message (icmp0)))
+ {
+ b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
+ next0 = SNAT_IN2OUT_NEXT_DROP;
+ goto out;
+ }
+
+ u32 now = (u32) vlib_time_now (sm->vlib_main);
+
+ ses0->state = SNAT_SESSION_ICMP_ACTIVE;
+ ses0->expire = now + sm->icmp_timeout;
+
+out:
+ *p_proto = protocol;
+ if (ses0)
+ {
+ p_value->addr = new_addr0;
+ p_value->fib_index = sm->outside_fib_index;
+ p_value->port = ses0->out.out_port;
+ }
+ *p_dont_translate = dont_translate;
+ if (d)
+ *(snat_det_session_t**)d = ses0;
+ if (e)
+ *(snat_det_map_t**)e = dm0;
+ return next0;
+}
+