vnet/vnet/nsh-gre/encap.c

   1 /*
   2  * Copyright (c) 2015 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/ethernet/ethernet.h>
  20 #include <vnet/nsh-gre/nsh_gre.h>
  21
  22 /* Statistics (not really errors) */
  23 #define foreach_nsh_gre_encap_error             \
  24 _(ENCAPSULATED, "good packets encapsulated")
  25
  26 static char * nsh_gre_encap_error_strings[] = {
  27 #define _(sym,string) string,
  28   foreach_nsh_gre_encap_error
  29 #undef _
  30 };
  31
  32 typedef enum {
  33 #define _(sym,str) NSH_GRE_ENCAP_ERROR_##sym,
  34     foreach_nsh_gre_encap_error
  35 #undef _
  36     NSH_GRE_ENCAP_N_ERROR,
  37 } nsh_gre_encap_error_t;
  38
  39 typedef enum {
  40     NSH_GRE_ENCAP_NEXT_IP4_LOOKUP,
  41     NSH_GRE_ENCAP_NEXT_DROP,
  42     NSH_GRE_ENCAP_N_NEXT,
  43 } nsh_gre_encap_next_t;
  44
  45 typedef struct {
  46   u32 tunnel_index;
  47 } nsh_gre_encap_trace_t;
  48
  49 u8 * format_nsh_gre_encap_trace (u8 * s, va_list * args)
  50 {
  51   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  52   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  53   nsh_gre_encap_trace_t * t = va_arg (*args, nsh_gre_encap_trace_t *);
  54
  55   s = format (s, "NSH-GRE-ENCAP: tunnel %d", t->tunnel_index);
  56   return s;
  57 }
  58
  59 static uword
  60 nsh_gre_encap (vlib_main_t * vm,
  61                vlib_node_runtime_t * node,
  62                vlib_frame_t * from_frame)
  63 {
  64   u32 n_left_from, next_index, * from, * to_next;
  65   nsh_gre_main_t * ngm = &nsh_gre_main;
  66   vnet_main_t * vnm = ngm->vnet_main;
  67   u32 pkts_encapsulated = 0;
  68   u16 old_l0 = 0, old_l1 = 0;
  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,
  80                            to_next, n_left_to_next);
  81
  82       while (n_left_from >= 4 && n_left_to_next >= 2)
  83         {
  84           u32 bi0, bi1;
  85           vlib_buffer_t * b0, * b1;
  86           u32 next0 = NSH_GRE_ENCAP_NEXT_IP4_LOOKUP;
  87           u32 next1 = NSH_GRE_ENCAP_NEXT_IP4_LOOKUP;
  88           vnet_hw_interface_t * hi0, * hi1;
  89           ip4_header_t * ip0, * ip1;
  90           u64 * copy_src0, * copy_dst0;
  91           u64 * copy_src1, * copy_dst1;
  92           nsh_gre_tunnel_t * t0, * t1;
  93           u16 new_l0, new_l1;
  94           ip_csum_t sum0, sum1;
  95
  96           /* Prefetch next iteration. */
  97           {
  98             vlib_buffer_t * p2, * p3;
  99
 100             p2 = vlib_get_buffer (vm, from[2]);
 101             p3 = vlib_get_buffer (vm, from[3]);
 102
 103             vlib_prefetch_buffer_header (p2, LOAD);
 104             vlib_prefetch_buffer_header (p3, LOAD);
 105
 106             CLIB_PREFETCH (p2->data, 2*CLIB_CACHE_LINE_BYTES, LOAD);
 107             CLIB_PREFETCH (p3->data, 2*CLIB_CACHE_LINE_BYTES, LOAD);
 108           }
 109
 110           bi0 = from[0];
 111           bi1 = from[1];
 112           to_next[0] = bi0;
 113           to_next[1] = bi1;
 114           from += 2;
 115           to_next += 2;
 116           n_left_to_next -= 2;
 117           n_left_from -= 2;
 118
 119           b0 = vlib_get_buffer (vm, bi0);
 120           b1 = vlib_get_buffer (vm, bi1);
 121
 122           hi0 = vnet_get_sup_hw_interface
 123             (vnm, vnet_buffer(b0)->sw_if_index[VLIB_TX]);
 124           hi1 = vnet_get_sup_hw_interface
 125             (vnm, vnet_buffer(b1)->sw_if_index[VLIB_TX]);
 126
 127           t0 = pool_elt_at_index (ngm->tunnels, hi0->dev_instance);
 128           t1 = pool_elt_at_index (ngm->tunnels, hi1->dev_instance);
 129
 130           ASSERT(vec_len(t0->rewrite) >= 24);
 131           ASSERT(vec_len(t1->rewrite) >= 24);
 132
 133           /* Apply the rewrite string. $$$$ vnet_rewrite? */
 134           vlib_buffer_advance (b0, -(word)_vec_len(t0->rewrite));
 135           vlib_buffer_advance (b1, -(word)_vec_len(t1->rewrite));
 136
 137           ip0 = vlib_buffer_get_current(b0);
 138           ip1 = vlib_buffer_get_current(b1);
 139           /* Copy the fixed header */
 140           copy_dst0 = (u64 *) ip0;
 141           copy_src0 = (u64 *) t0->rewrite;
 142           copy_dst1 = (u64 *) ip1;
 143           copy_src1 = (u64 *) t1->rewrite;
 144
 145           copy_dst0[0] = copy_src0[0];
 146           copy_dst0[1] = copy_src0[1];
 147           copy_dst0[2] = copy_src0[2];
 148
 149           copy_dst1[0] = copy_src1[0];
 150           copy_dst1[1] = copy_src1[1];
 151           copy_dst1[2] = copy_src1[2];
 152
 153           /* If there are TLVs to copy, do so */
 154           if (PREDICT_FALSE (_vec_len(t0->rewrite) > 24))
 155             memcpy (&copy_dst0[3], t0->rewrite + 24 ,
 156                     _vec_len (t0->rewrite)-24);
 157
 158           if (PREDICT_FALSE (_vec_len(t1->rewrite) > 24))
 159             memcpy (&copy_dst1[3], t1->rewrite + 24 ,
 160                     _vec_len (t1->rewrite)-24);
 161
 162           /* fix the <bleep>ing outer-IP checksums */
 163           sum0 = ip0->checksum;
 164           /* old_l0 always 0, see the rewrite setup */
 165           new_l0 =
 166             clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
 167
 168           sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
 169                                  length /* changed member */);
 170           ip0->checksum = ip_csum_fold (sum0);
 171           ip0->length = new_l0;
 172
 173           sum1 = ip1->checksum;
 174           /* old_l1 always 1, see the rewrite setup */
 175           new_l1 =
 176             clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1));
 177
 178           sum1 = ip_csum_update (sum1, old_l1, new_l1, ip4_header_t,
 179                                  length /* changed member */);
 180           ip1->checksum = ip_csum_fold (sum1);
 181           ip1->length = new_l1;
 182
 183           /* Reset to look up tunnel partner in the configured FIB */
 184           vnet_buffer(b0)->sw_if_index[VLIB_TX] = t0->encap_fib_index;
 185           vnet_buffer(b1)->sw_if_index[VLIB_TX] = t1->encap_fib_index;
 186           pkts_encapsulated += 2;
 187
 188           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 189             {
 190               nsh_gre_encap_trace_t *tr =
 191                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 192               tr->tunnel_index = t0 - ngm->tunnels;
 193             }
 194
 195           if (PREDICT_FALSE(b1->flags & VLIB_BUFFER_IS_TRACED))
 196             {
 197               nsh_gre_encap_trace_t *tr =
 198                 vlib_add_trace (vm, node, b1, sizeof (*tr));
 199               tr->tunnel_index = t1 - ngm->tunnels;
 200             }
 201
 202           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
 203                                            to_next, n_left_to_next,
 204                                            bi0, bi1, next0, next1);
 205         }
 206
 207       while (n_left_from > 0 && n_left_to_next > 0)
 208         {
 209           u32 bi0;
 210           vlib_buffer_t * b0;
 211           u32 next0 = NSH_GRE_ENCAP_NEXT_IP4_LOOKUP;
 212           vnet_hw_interface_t * hi0;
 213           ip4_header_t * ip0;
 214           u64 * copy_src0, * copy_dst0;
 215           nsh_gre_tunnel_t * t0;
 216           u16 new_l0;
 217           ip_csum_t sum0;
 218
 219           bi0 = from[0];
 220           to_next[0] = bi0;
 221           from += 1;
 222           to_next += 1;
 223           n_left_from -= 1;
 224           n_left_to_next -= 1;
 225
 226           b0 = vlib_get_buffer (vm, bi0);
 227
 228           /* 1-wide cache? */
 229           hi0 = vnet_get_sup_hw_interface
 230             (vnm, vnet_buffer(b0)->sw_if_index[VLIB_TX]);
 231
 232           t0 = pool_elt_at_index (ngm->tunnels, hi0->dev_instance);
 233
 234           ASSERT(vec_len(t0->rewrite) >= 24);
 235
 236           /* Apply the rewrite string. $$$$ vnet_rewrite? */
 237           vlib_buffer_advance (b0, -(word)_vec_len(t0->rewrite));
 238
 239           ip0 = vlib_buffer_get_current(b0);
 240           /* Copy the fixed header */
 241           copy_dst0 = (u64 *) ip0;
 242           copy_src0 = (u64 *) t0->rewrite;
 243           copy_dst0[0] = copy_src0[0];
 244           copy_dst0[1] = copy_src0[1];
 245           copy_dst0[2] = copy_src0[2];
 246
 247           /* If there are TLVs to copy, do so */
 248           if (PREDICT_FALSE (_vec_len(t0->rewrite) > 24))
 249             memcpy (&copy_dst0[3], t0->rewrite + 24 ,
 250                     _vec_len (t0->rewrite)-24);
 251
 252           /* fix the <bleep>ing outer-IP checksum */
 253           sum0 = ip0->checksum;
 254           /* old_l0 always 0, see the rewrite setup */
 255           new_l0 =
 256             clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
 257
 258           sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
 259                                  length /* changed member */);
 260           ip0->checksum = ip_csum_fold (sum0);
 261           ip0->length = new_l0;
 262
 263           /* Reset to look up tunnel partner in the configured FIB */
 264           vnet_buffer(b0)->sw_if_index[VLIB_TX] = t0->encap_fib_index;
 265           pkts_encapsulated ++;
 266
 267           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 268             {
 269               nsh_gre_encap_trace_t *tr =
 270                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 271               tr->tunnel_index = t0 - ngm->tunnels;
 272             }
 273           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 274                                            to_next, n_left_to_next,
 275                                            bi0, next0);
 276         }
 277
 278       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 279     }
 280   vlib_node_increment_counter (vm, node->node_index,
 281                                NSH_GRE_ENCAP_ERROR_ENCAPSULATED,
 282                                pkts_encapsulated);
 283   return from_frame->n_vectors;
 284 }
 285
 286 VLIB_REGISTER_NODE (nsh_gre_encap_node) = {
 287   .function = nsh_gre_encap,
 288   .name = "nsh-gre-encap",
 289   .vector_size = sizeof (u32),
 290   .format_trace = format_nsh_gre_encap_trace,
 291   .type = VLIB_NODE_TYPE_INTERNAL,
 292
 293   .n_errors = ARRAY_LEN(nsh_gre_encap_error_strings),
 294   .error_strings = nsh_gre_encap_error_strings,
 295
 296   .n_next_nodes = NSH_GRE_ENCAP_N_NEXT,
 297
 298   //  add dispositions here
 299   .next_nodes = {
 300         [NSH_GRE_ENCAP_NEXT_IP4_LOOKUP] = "ip4-lookup",
 301         [NSH_GRE_ENCAP_NEXT_DROP] = "error-drop",
 302   },
 303 };