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.h>
  20 #include <vnet/ethernet/ethernet.h>
  21 #include <vnet/lisp-gpe/lisp_gpe.h>
  22 #include <vnet/lisp-gpe/lisp_gpe_packet.h>
  23 #include <nsh/nsh.h>
  24 #include <nsh/nsh_packet.h>
  25 #include <nsh/nsh-md2-ioam/nsh_md2_ioam.h>
  26 #include <nsh/nsh-md2-ioam/nsh_md2_ioam_util.h>
  27 #include <vnet/fib/ip6_fib.h>
  28 #include <vnet/fib/ip4_fib.h>
  29 #include <vnet/fib/fib_entry.h>
  30
  31 /* Statistics (not really errors) */
  32 #define foreach_nsh_md2_ioam_encap_transit_error    \
  33 _(ENCAPSULATED, "good packets encapsulated")
  34
  35 static char *nsh_md2_ioam_encap_transit_error_strings[] = {
  36 #define _(sym,string) string,
  37   foreach_nsh_md2_ioam_encap_transit_error
  38 #undef _
  39 };
  40
  41 typedef enum
  42 {
  43 #define _(sym,str) NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_ERROR_##sym,
  44   foreach_nsh_md2_ioam_encap_transit_error
  45 #undef _
  46     NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_N_ERROR,
  47 } nsh_md2_ioam_encap_transit_error_t;
  48
  49 typedef enum
  50 {
  51   NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT,
  52   NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP,
  53   NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_N_NEXT
  54 } nsh_md2_ioam_encap_transit_next_t;
  55
  56
  57 /* *INDENT-OFF* */
  58 VNET_FEATURE_INIT (nsh_md2_ioam_encap_transit, static) =
  59 {
  60   .arc_name = "ip4-output",
  61   .node_name = "nsh-md2-ioam-encap-transit",
  62 };
  63 /* *INDENT-ON* */
  64
  65
  66 static uword
  67 nsh_md2_ioam_encap_transit (vlib_main_t * vm,
  68                             vlib_node_runtime_t * node,
  69                             vlib_frame_t * from_frame)
  70 {
  71   u32 n_left_from, next_index, *from, *to_next;
  72
  73   from = vlib_frame_vector_args (from_frame);
  74   n_left_from = from_frame->n_vectors;
  75
  76   next_index = node->cached_next_index;
  77
  78   while (n_left_from > 0)
  79     {
  80       u32 n_left_to_next;
  81
  82       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  83
  84
  85       while (n_left_from > 0 && n_left_to_next > 0)
  86         {
  87           u32 bi0;
  88           vlib_buffer_t *b0;
  89           u32 next0 = NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT;
  90
  91           bi0 = from[0];
  92           to_next[0] = bi0;
  93           from += 1;
  94           to_next += 1;
  95           n_left_from -= 1;
  96           n_left_to_next -= 1;
  97           ip4_header_t *ip0;
  98           u32 iph_offset = 0;
  99
 100           b0 = vlib_get_buffer (vm, bi0);
 101           iph_offset = vnet_buffer (b0)->ip.save_rewrite_length;
 102           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0)
 103                                   + iph_offset);
 104
 105           /* just forward non ipv4 packets */
 106           if (PREDICT_FALSE
 107               ((ip0->ip_version_and_header_length & 0xF0) == 0x40))
 108             {
 109               /* ipv4 packets */
 110               udp_header_t *udp_hdr0 = (udp_header_t *) (ip0 + 1);
 111               if (PREDICT_FALSE
 112                   ((ip0->protocol == IP_PROTOCOL_UDP) &&
 113                    (clib_net_to_host_u16 (udp_hdr0->dst_port) ==
 114                     UDP_DST_PORT_lisp_gpe)))
 115                 {
 116
 117                   /* Check the iOAM header */
 118                   lisp_gpe_header_t *lisp_gpe_hdr0 =
 119                     (lisp_gpe_header_t *) (udp_hdr0 + 1);
 120                   nsh_base_header_t *nsh_hdr =
 121                     (nsh_base_header_t *) (lisp_gpe_hdr0 + 1);
 122
 123                   if (PREDICT_FALSE
 124                       (lisp_gpe_hdr0->next_protocol ==
 125                        LISP_GPE_NEXT_PROTO_NSH) && (nsh_hdr->md_type == 2))
 126                     {
 127                       uword *t = NULL;
 128                       nsh_md2_ioam_main_t *hm = &nsh_md2_ioam_main;
 129                       fib_prefix_t key4;
 130                       clib_memset (&key4, 0, sizeof (key4));
 131                       key4.fp_proto = FIB_PROTOCOL_IP4;
 132                       key4.fp_addr.ip4.as_u32 = ip0->dst_address.as_u32;
 133                       t = hash_get_mem (hm->dst_by_ip4, &key4);
 134                       if (t)
 135                         {
 136                           vlib_buffer_advance (b0,
 137                                                (word) (sizeof
 138                                                        (ethernet_header_t)));
 139                           nsh_md2_ioam_encap_decap_ioam_v4_one_inline (vm,
 140                                                                        node,
 141                                                                        b0,
 142                                                                        &next0,
 143                                                                        NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP,
 144                                                                        1
 145                                                                        /* use_adj */
 146                             );
 147                           vlib_buffer_advance (b0,
 148                                                -(word) (sizeof
 149                                                         (ethernet_header_t)));
 150                         }
 151                     }
 152                 }
 153             }
 154
 155           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 156                                            n_left_to_next, bi0, next0);
 157         }
 158
 159       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 160     }
 161
 162   return from_frame->n_vectors;
 163 }
 164
 165 extern u8 *format_nsh_node_map_trace (u8 * s, va_list * args);
 166 /* *INDENT-OFF* */
 167 VLIB_REGISTER_NODE (nsh_md2_ioam_encap_transit_node) = {
 168   .function = nsh_md2_ioam_encap_transit,
 169   .name = "nsh-md2-ioam-encap-transit",
 170   .vector_size = sizeof (u32),
 171   .format_trace = format_nsh_node_map_trace,
 172   .type = VLIB_NODE_TYPE_INTERNAL,
 173
 174   .n_errors = ARRAY_LEN(nsh_md2_ioam_encap_transit_error_strings),
 175   .error_strings = nsh_md2_ioam_encap_transit_error_strings,
 176
 177   .n_next_nodes = NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_N_NEXT,
 178
 179   .next_nodes = {
 180         [NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT] = "interface-output",
 181         [NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP] = "error-drop",
 182   },
 183
 184 };
 185 /* *INDENT-ON* */
 186
 187
 188 /*
 189  * fd.io coding-style-patch-verification: ON
 190  *
 191  * Local Variables:
 192  * eval: (c-set-style "gnu")
 193  * End:
 194  */