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   .runs_before = VNET_FEATURES ("adj-midchain-tx"),
  63 };
  64 /* *INDENT-ON* */
  65
  66
  67 static uword
  68 nsh_md2_ioam_encap_transit (vlib_main_t * vm,
  69                             vlib_node_runtime_t * node,
  70                             vlib_frame_t * from_frame)
  71 {
  72   u32 n_left_from, next_index, *from, *to_next;
  73
  74   from = vlib_frame_vector_args (from_frame);
  75   n_left_from = from_frame->n_vectors;
  76
  77   next_index = node->cached_next_index;
  78
  79   while (n_left_from > 0)
  80     {
  81       u32 n_left_to_next;
  82
  83       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  84
  85
  86       while (n_left_from > 0 && n_left_to_next > 0)
  87         {
  88           u32 bi0;
  89           vlib_buffer_t *b0;
  90           u32 next0 = NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT;
  91
  92           bi0 = from[0];
  93           to_next[0] = bi0;
  94           from += 1;
  95           to_next += 1;
  96           n_left_from -= 1;
  97           n_left_to_next -= 1;
  98           ip4_header_t *ip0;
  99           u32 iph_offset = 0;
 100
 101           b0 = vlib_get_buffer (vm, bi0);
 102           iph_offset = vnet_buffer (b0)->ip.save_rewrite_length;
 103           ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0)
 104                                   + iph_offset);
 105
 106           /* just forward non ipv4 packets */
 107           if (PREDICT_FALSE
 108               ((ip0->ip_version_and_header_length & 0xF0) == 0x40))
 109             {
 110               /* ipv4 packets */
 111               udp_header_t *udp_hdr0 = (udp_header_t *) (ip0 + 1);
 112               if (PREDICT_FALSE
 113                   ((ip0->protocol == IP_PROTOCOL_UDP) &&
 114                    (clib_net_to_host_u16 (udp_hdr0->dst_port) ==
 115                     UDP_DST_PORT_lisp_gpe)))
 116                 {
 117
 118                   /* Check the iOAM header */
 119                   lisp_gpe_header_t *lisp_gpe_hdr0 =
 120                     (lisp_gpe_header_t *) (udp_hdr0 + 1);
 121                   nsh_base_header_t *nsh_hdr =
 122                     (nsh_base_header_t *) (lisp_gpe_hdr0 + 1);
 123
 124                   if (PREDICT_FALSE
 125                       (lisp_gpe_hdr0->next_protocol ==
 126                        LISP_GPE_NEXT_PROTO_NSH) && (nsh_hdr->md_type == 2))
 127                     {
 128                       uword *t = NULL;
 129                       nsh_md2_ioam_main_t *hm = &nsh_md2_ioam_main;
 130                       fib_prefix_t key4;
 131                       clib_memset (&key4, 0, sizeof (key4));
 132                       key4.fp_proto = FIB_PROTOCOL_IP4;
 133                       key4.fp_addr.ip4.as_u32 = ip0->dst_address.as_u32;
 134                       t = hash_get_mem (hm->dst_by_ip4, &key4);
 135                       if (t)
 136                         {
 137                           vlib_buffer_advance (b0,
 138                                                (word) (sizeof
 139                                                        (ethernet_header_t)));
 140                           nsh_md2_ioam_encap_decap_ioam_v4_one_inline (vm,
 141                                                                        node,
 142                                                                        b0,
 143                                                                        &next0,
 144                                                                        NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP,
 145                                                                        1
 146                                                                        /* use_adj */
 147                             );
 148                           vlib_buffer_advance (b0,
 149                                                -(word) (sizeof
 150                                                         (ethernet_header_t)));
 151                         }
 152                     }
 153                 }
 154             }
 155
 156           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 157                                            n_left_to_next, bi0, next0);
 158         }
 159
 160       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 161     }
 162
 163   return from_frame->n_vectors;
 164 }
 165
 166 extern u8 *format_nsh_node_map_trace (u8 * s, va_list * args);
 167 /* *INDENT-OFF* */
 168 VLIB_REGISTER_NODE (nsh_md2_ioam_encap_transit_node) = {
 169   .function = nsh_md2_ioam_encap_transit,
 170   .name = "nsh-md2-ioam-encap-transit",
 171   .vector_size = sizeof (u32),
 172   .format_trace = format_nsh_node_map_trace,
 173   .type = VLIB_NODE_TYPE_INTERNAL,
 174
 175   .n_errors = ARRAY_LEN(nsh_md2_ioam_encap_transit_error_strings),
 176   .error_strings = nsh_md2_ioam_encap_transit_error_strings,
 177
 178   .n_next_nodes = NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_N_NEXT,
 179
 180   .next_nodes = {
 181         [NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_OUTPUT] = "interface-output",
 182         [NSH_MD2_IOAM_ENCAP_TRANSIT_IOAM_NEXT_DROP] = "error-drop",
 183   },
 184
 185 };
 186 /* *INDENT-ON* */
 187
 188
 189 /*
 190  * fd.io coding-style-patch-verification: ON
 191  *
 192  * Local Variables:
 193  * eval: (c-set-style "gnu")
 194  * End:
 195  */