1/*
2 * ip/ip6_neighbor.h: IP6 NS transmit
3 *
4 * Copyright (c) 2019 Cisco and/or its affiliates.
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18#ifndef __IP6_NEIGHBOR_H__
19#define __IP6_NEIGHBOR_H__
20
21#include <vlib/vlib.h>
22#include <vnet/ip/format.h>
23#include <vnet/ip/ip6.h>
24#include <vnet/ip/ip6_link.h>
25#include <vnet/ip/icmp46_packet.h>
26#include <vnet/ethernet/ethernet.h>
27#include <vnet/adj/adj_internal.h>
28
29/* Template used to generate IP6 neighbor solicitation packets. */
30extern vlib_packet_template_t ip6_neighbor_packet_template;
31
32extern void ip6_neighbor_advertise (vlib_main_t * vm,
33				    vnet_main_t * vnm,
34				    u32 sw_if_index,
35				    const ip6_address_t * addr);
36
37extern void ip6_neighbor_probe_dst (const ip_adjacency_t * adj,
38				    const ip6_address_t * dst);
39
40always_inline vlib_buffer_t *
41ip6_neighbor_probe (vlib_main_t * vm,
42		    vnet_main_t * vnm,
43		    const ip_adjacency_t * adj,
44		    const ip6_address_t * src, const ip6_address_t * dst)
45{
46  icmp6_neighbor_solicitation_header_t *h0;
47  vnet_hw_interface_t *hw_if0;
48  vlib_buffer_t *b0;
49  int bogus_length;
50  u32 bi0 = 0;
51
52  h0 = vlib_packet_template_get_packet
53    (vm, &ip6_neighbor_packet_template, &bi0);
54  if (!h0)
55    return NULL;;
56
57  b0 = vlib_get_buffer (vm, bi0);
58
59  hw_if0 = vnet_get_sup_hw_interface (vnm, adj->rewrite_header.sw_if_index);
60
61  /*
62   * Destination address is a solicited node multicast address.
63   * We need to fill in
64   * the low 24 bits with low 24 bits of target's address.
65   */
66  h0->ip.src_address = *src;
67  h0->ip.dst_address.as_u8[13] = dst->as_u8[13];
68  h0->ip.dst_address.as_u8[14] = dst->as_u8[14];
69  h0->ip.dst_address.as_u8[15] = dst->as_u8[15];
70
71  h0->neighbor.target_address = *dst;
72
73  clib_memcpy (h0->link_layer_option.ethernet_address,
74	       hw_if0->hw_address, vec_len (hw_if0->hw_address));
75
76  /* $$$$ appears we need this; why is the checksum non-zero? */
77  h0->neighbor.icmp.checksum = 0;
78  h0->neighbor.icmp.checksum =
79    ip6_tcp_udp_icmp_compute_checksum (vm, 0, &h0->ip, &bogus_length);
80
81  ASSERT (bogus_length == 0);
82  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0);
83
84  vnet_buffer (b0)->sw_if_index[VLIB_TX] = adj->rewrite_header.sw_if_index;
85
86  /* Use the link's mcast adj to ship the packet */
87  vnet_buffer (b0)->ip.adj_index[VLIB_TX] =
88    ip6_link_get_mcast_adj (adj->rewrite_header.sw_if_index);
89  adj = adj_get (vnet_buffer (b0)->ip.adj_index[VLIB_TX]);
90
91  b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
92
93  {
94    vlib_frame_t *f = vlib_get_frame_to_node (vm, adj->ia_node_index);
95    u32 *to_next = vlib_frame_vector_args (f);
96    to_next[0] = bi0;
97    f->n_vectors = 1;
98    vlib_put_frame_to_node (vm, adj->ia_node_index, f);
99  }
100
101  return b0;
102}
103
104#endif
105
106/*
107 * fd.io coding-style-patch-verification: ON
108 *
109 * Local Variables:
110 * eval: (c-set-style "gnu")
111 * End:
112 */
113