src/plugins/nsh/nsh-md2-ioam/md2_ioam_transit.c

   1  /*
   2   * Copyright (c) 2017 Cisco and/or its affiliates.
   3   * Licensed under the Apache License, Version 2.0 (the "License");
   4   * you may not use this file except in compliance with the License.
   5   * You may obtain a copy of the License at:
   6   *
   7   *     http://www.apache.org/licenses/LICENSE-2.0
   8   *
   9   * Unless required by applicable law or agreed to in writing, software
  10   * distributed under the License is distributed on an "AS IS" BASIS,
  11   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12   * See the License for the specific language governing permissions and
  13   * limitations under the License.
  14   */
  15 #include <vppinfra/error.h>
  16 #include <vppinfra/hash.h>
  17 #include <vnet/vnet.h>
  18 #include <vnet/ip/ip.h>
  19 #include <vnet/udp/udp_local.h>
  20 #include <vnet/ethernet/ethernet.h>
  21 #include <lisp/lisp-gpe/lisp_gpe_packet.h>
  22 #include <nsh/nsh.h>
  23 #include <nsh/nsh_packet.h>
  24 #include <nsh/nsh-md2-ioam/nsh_md2_ioam.h>
  25 #include <nsh/nsh-md2-ioam/nsh_md2_ioam_util.h>
  26 #include <vnet/fib/ip6_fib.h>
  27 #include <vnet/fib/ip4_fib.h>
  28 #include <vnet/fib/fib_entry.h>
  29
  30 /* Statistics (not really errors) */
  31 #define foreach_nsh_md2_ioam_encap_transit_error    \
  32 _(ENCAPSULATED, "good packets encapsulated")
  33
  34 static char *nsh_md2_ioam_encap_transit_error_strings[] = {
  35 #define _(sym,string) string,
  36   foreach_nsh_md2_ioam_encap_transit_error
  37 #undef _
  38 };
  39
  40 typedef enum
  41 {
  42 #define _(sym,str) NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_ERROR_##sym,
  43   foreach_nsh_md2_ioam_encap_transit_error
  44 #undef _
  45     NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_N_ERROR,
  46 } nsh_md2_ioam_encap_transit_error_t;
  47
  48 typedef enum
  49 {
  50   NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT,
  51   NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP,
  52   NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_N_NEXT
  53 } nsh_md2_ioam_encap_transit_next_t;
  54
  55
  56 VNET_FEATURE_INIT (nsh_md2_ioam_encap_transit, static) =
  57 {
  58   .arc_name = "ip4-output",
  59   .node_name = "nsh-md2-ioam-encap-transit",
  60 };
  61
  62
  63 static uword
  64 nsh_md2_ioam_encap_transit (vlib_main_t * vm,
  65                             vlib_node_runtime_t * node,
  66                             vlib_frame_t * from_frame)
  67 {
  68   u32 n_left_from, next_index, *from, *to_next;
  69
  70   from = vlib_frame_vector_args (from_frame);
  71   n_left_from = from_frame->n_vectors;
  72
  73   next_index = node->cached_next_index;
  74
  75   while (n_left_from > 0)
  76     {
  77       u32 n_left_to_next;
  78
  79       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  80
  81
  82       while (n_left_from > 0 && n_left_to_next > 0)
  83         {
  84           u32 bi0;
  85           vlib_buffer_t *b0;
  86           u32 next0 = NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT;
  87
  88           bi0 = from[0];
  89           to_next[0] = bi0;
  90           from += 1;
  91           to_next += 1;
  92           n_left_from -= 1;
  93           n_left_to_next -= 1;
  94           ip4_header_t *ip0;
  95           u32 iph_offset = 0;
  96
  97           b0 = vlib_get_buffer (vm, bi0);
  98           iph_offset = vnet_buffer (b0)->ip.save_rewrite_length;
  99           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0)
 100                                   + iph_offset);
 101
 102           /* just forward non ipv4 packets */
 103           if (PREDICT_FALSE
 104               ((ip0->ip_version_and_header_length & 0xF0) == 0x40))
 105             {
 106               /* ipv4 packets */
 107               udp_header_t *udp_hdr0 = (udp_header_t *) (ip0 + 1);
 108               if (PREDICT_FALSE
 109                   ((ip0->protocol == IP_PROTOCOL_UDP) &&
 110                    (clib_net_to_host_u16 (udp_hdr0->dst_port) ==
 111                     UDP_DST_PORT_lisp_gpe)))
 112                 {
 113
 114                   /* Check the iOAM header */
 115                   lisp_gpe_header_t *lisp_gpe_hdr0 =
 116                     (lisp_gpe_header_t *) (udp_hdr0 + 1);
 117                   nsh_base_header_t *nsh_hdr =
 118                     (nsh_base_header_t *) (lisp_gpe_hdr0 + 1);
 119
 120                   if (PREDICT_FALSE
 121                       (lisp_gpe_hdr0->next_protocol ==
 122                        LISP_GPE_NEXT_PROTO_NSH) && (nsh_hdr->md_type == 2))
 123                     {
 124                       uword *t = NULL;
 125                       nsh_md2_ioam_main_t *hm = &nsh_md2_ioam_main;
 126                       fib_prefix_t key4;
 127                       clib_memset (&key4, 0, sizeof (key4));
 128                       key4.fp_proto = FIB_PROTOCOL_IP4;
 129                       key4.fp_addr.ip4.as_u32 = ip0->dst_address.as_u32;
 130                       t = hash_get_mem (hm->dst_by_ip4, &key4);
 131                       if (t)
 132                         {
 133                           vlib_buffer_advance (b0,
 134                                                (word) (sizeof
 135                                                        (ethernet_header_t)));
 136                           nsh_md2_ioam_encap_decap_ioam_v4_one_inline (vm,
 137                                                                        node,
 138                                                                        b0,
 139                                                                        &next0,
 140                                                                        NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP,
 141                                                                        1
 142                                                                        /* use_adj */
 143                             );
 144                           vlib_buffer_advance (b0,
 145                                                -(word) (sizeof
 146                                                         (ethernet_header_t)));
 147                         }
 148                     }
 149                 }
 150             }
 151
 152           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 153                                            n_left_to_next, bi0, next0);
 154         }
 155
 156       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 157     }
 158
 159   return from_frame->n_vectors;
 160 }
 161
 162 extern u8 *format_nsh_node_map_trace (u8 * s, va_list * args);
 163 VLIB_REGISTER_NODE (nsh_md2_ioam_encap_transit_node) = {
 164   .function = nsh_md2_ioam_encap_transit,
 165   .name = "nsh-md2-ioam-encap-transit",
 166   .vector_size = sizeof (u32),
 167   .format_trace = format_nsh_node_map_trace,
 168   .type = VLIB_NODE_TYPE_INTERNAL,
 169
 170   .n_errors = ARRAY_LEN(nsh_md2_ioam_encap_transit_error_strings),
 171   .error_strings = nsh_md2_ioam_encap_transit_error_strings,
 172
 173   .n_next_nodes = NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_N_NEXT,
 174
 175   .next_nodes = {
 176         [NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT] = "interface-output",
 177         [NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP] = "error-drop",
 178   },
 179
 180 };
 181
 182
 183 /*
 184  * fd.io coding-style-patch-verification: ON
 185  *
 186  * Local Variables:
 187  * eval: (c-set-style "gnu")
 188  * End:
 189  */