vnet/vnet/sr/sr_replicate.c

   1 /*
   2  * sr_replicate.c: ipv6 segment routing replicator for multicast
   3  *
   4  * Copyright (c) 2016 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 #include <vlib/vlib.h>
  19 #include <vnet/vnet.h>
  20 #include <vnet/pg/pg.h>
  21 #include <vnet/sr/sr.h>
  22 #include <vnet/devices/dpdk/dpdk.h>
  23 #include <vnet/dpdk_replication.h>
  24 #include <vnet/ip/ip.h>
  25
  26 #include <vppinfra/hash.h>
  27 #include <vppinfra/error.h>
  28 #include <vppinfra/elog.h>
  29
  30 typedef struct {
  31   /* convenience */
  32   vlib_main_t * vlib_main;
  33   vnet_main_t * vnet_main;
  34 } sr_replicate_main_t;
  35
  36 sr_replicate_main_t sr_replicate_main;
  37
  38 vlib_node_registration_t sr_replicate_node;
  39
  40
  41 typedef struct {
  42   ip6_address_t src, dst;
  43   u16 length;
  44   u32 next_index;
  45   u32 tunnel_index;
  46   u8 sr[256];
  47 } sr_replicate_trace_t;
  48
  49 /* packet trace format function */
  50 static u8 * format_sr_replicate_trace (u8 * s, va_list * args)
  51 {
  52   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  53   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  54   sr_replicate_trace_t * t = va_arg (*args, sr_replicate_trace_t *);
  55   ip6_main_t * im = &ip6_main;
  56   ip6_sr_main_t * sm = &sr_main;
  57   ip6_sr_tunnel_t *tun = pool_elt_at_index (sm->tunnels, t->tunnel_index);
  58   ip6_fib_t * rx_fib, * tx_fib;
  59
  60   rx_fib = find_ip6_fib_by_table_index_or_id (im, tun->rx_fib_index,
  61                                               IP6_ROUTE_FLAG_FIB_INDEX);
  62
  63   tx_fib = find_ip6_fib_by_table_index_or_id (im, tun->tx_fib_index,
  64                                               IP6_ROUTE_FLAG_FIB_INDEX);
  65
  66   s = format
  67     (s, "SR-REPLICATE: next %s ip6 src %U dst %U len %u\n"
  68      "           rx-fib-id %d tx-fib-id %d\n%U",
  69      "ip6-lookup",
  70      format_ip6_address, &t->src,
  71      format_ip6_address, &t->dst, t->length,
  72      rx_fib->table_id, tx_fib->table_id,
  73      format_ip6_sr_header, t->sr, 0 /* print_hmac */);
  74   return s;
  75
  76 }
  77
  78 vlib_node_registration_t sr_replicate_node;
  79
  80 #define foreach_sr_replicate_error \
  81 _(REPLICATED, "sr packets replicated") \
  82 _(NO_BUFFERS, "error allocating buffers for replicas") \
  83 _(NO_REPLICAS, "no replicas were needed") \
  84 _(NO_BUFFER_DROPS, "sr no buffer drops")
  85
  86 typedef enum {
  87 #define _(sym,str) SR_REPLICATE_ERROR_##sym,
  88   foreach_sr_replicate_error
  89 #undef _
  90   SR_REPLICATE_N_ERROR,
  91 } sr_replicate_error_t;
  92
  93 static char * sr_replicate_error_strings[] = {
  94 #define _(sym,string) string,
  95   foreach_sr_replicate_error
  96 #undef _
  97 };
  98
  99 typedef enum {
 100   SR_REPLICATE_NEXT_IP6_LOOKUP,
 101   SR_REPLICATE_N_NEXT,
 102 } sr_replicate_next_t;
 103
 104 static uword
 105 sr_replicate_node_fn (vlib_main_t * vm,
 106                   vlib_node_runtime_t * node,
 107                   vlib_frame_t * frame)
 108 {
 109   u32 n_left_from, * from, * to_next;
 110   sr_replicate_next_t next_index;
 111   int pkts_replicated = 0;
 112   ip6_sr_main_t * sm = &sr_main;
 113   int no_buffer_drops = 0;
 114   vlib_buffer_free_list_t * fl;
 115   unsigned socket_id = rte_socket_id();
 116   vlib_buffer_main_t * bm = vm->buffer_main;
 117
 118   from = vlib_frame_vector_args (frame);
 119   n_left_from = frame->n_vectors;
 120   next_index = node->cached_next_index;
 121
 122   fl = vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
 123
 124   while (n_left_from > 0)
 125     {
 126       u32 n_left_to_next;
 127
 128       vlib_get_next_frame (vm, node, next_index,
 129                            to_next, n_left_to_next);
 130
 131       while (n_left_from > 0 && n_left_to_next > 0)
 132         {
 133           u32 bi0, hdr_bi0;
 134           vlib_buffer_t * b0, * orig_b0;
 135           struct rte_mbuf * orig_mb0 = 0, * hdr_mb0 = 0, * clone0 = 0;
 136           struct rte_mbuf ** hdr_vec = 0, ** rte_mbuf_vec = 0;
 137           ip6_sr_policy_t * pol0 = 0;
 138           ip6_sr_tunnel_t * t0 = 0;
 139           ip6_sr_header_t * hdr_sr0 = 0;
 140           ip6_header_t * ip0 = 0, * hdr_ip0 = 0;
 141           int num_replicas = 0;
 142           int i;
 143
 144           bi0 = from[0];
 145
 146           b0 = vlib_get_buffer (vm, bi0);
 147           orig_b0 = b0;
 148
 149           pol0 = pool_elt_at_index (sm->policies,
 150                                     vnet_buffer(b0)->ip.save_protocol);
 151
 152           ip0 = vlib_buffer_get_current (b0);
 153           /* Skip forward to the punch-in point */
 154           vlib_buffer_advance (b0, sizeof(*ip0));
 155
 156           orig_mb0 = rte_mbuf_from_vlib_buffer (b0);
 157
 158           i16 delta0 = vlib_buffer_length_in_chain (vm, orig_b0)
 159             - (i16) orig_mb0->pkt_len;
 160
 161           u16 new_data_len0 = (u16)((i16) orig_mb0->data_len + delta0);
 162           u16 new_pkt_len0  = (u16)((i16) orig_mb0->pkt_len + delta0);
 163
 164           orig_mb0->data_len = new_data_len0;
 165           orig_mb0->pkt_len = new_pkt_len0;
 166           orig_mb0->data_off = (u16)(RTE_PKTMBUF_HEADROOM + b0->current_data);
 167
 168           /*
 169             Before entering loop determine if we can allocate:
 170             - all the new HEADER RTE_MBUFs and assign them to a vector
 171             - all the clones
 172
 173             if successful, then iterate over vectors of resources
 174
 175            */
 176           num_replicas = vec_len (pol0->tunnel_indices);
 177
 178           if (PREDICT_FALSE(num_replicas == 0))
 179             {
 180               b0->error = node->errors[SR_REPLICATE_ERROR_NO_REPLICAS];
 181               goto do_trace0;
 182             }
 183
 184           vec_reset_length (hdr_vec);
 185           vec_reset_length (rte_mbuf_vec);
 186
 187           for (i=0; i < num_replicas; i++)
 188             {
 189               hdr_mb0 = rte_pktmbuf_alloc(bm->pktmbuf_pools[socket_id]);
 190
 191               if (i < (num_replicas - 1) )
 192                 /* Not the last tunnel to process */
 193                 clone0 = rte_pktmbuf_clone
 194                     (orig_mb0, bm->pktmbuf_pools[socket_id]);
 195               else
 196                   /* Last tunnel to process, use original MB */
 197                 clone0 = orig_mb0;
 198
 199
 200               if (PREDICT_FALSE( !clone0 || !hdr_mb0 ))
 201                 {
 202                   b0->error = node->errors[SR_REPLICATE_ERROR_NO_BUFFERS];
 203
 204                   vec_foreach_index (i, rte_mbuf_vec)
 205                     {
 206                       rte_pktmbuf_free(rte_mbuf_vec[i]);
 207                     }
 208                   vec_free (rte_mbuf_vec);
 209
 210                   vec_foreach_index (i, hdr_vec)
 211                     {
 212                       rte_pktmbuf_free(hdr_vec[i]);
 213                     }
 214                   vec_free (hdr_vec);
 215
 216                   goto do_trace0;
 217                 }
 218
 219               vec_add1 (hdr_vec, hdr_mb0);
 220               vec_add1 (rte_mbuf_vec, clone0);
 221
 222             }
 223
 224           for (i=0; i < num_replicas; i++)
 225             {
 226               vlib_buffer_t * hdr_b0;
 227
 228               t0 = vec_elt_at_index (sm->tunnels, pol0->tunnel_indices[i]);
 229
 230               /* Our replicas */
 231               hdr_mb0 = hdr_vec[i];
 232               clone0 = rte_mbuf_vec[i];
 233
 234               hdr_mb0->data_len = sizeof (*ip0) + vec_len (t0->rewrite);
 235               hdr_mb0->pkt_len = hdr_mb0->data_len +
 236                   vlib_buffer_length_in_chain (vm, orig_b0);
 237
 238               hdr_b0 = vlib_buffer_from_rte_mbuf (hdr_mb0);
 239
 240               vlib_buffer_init_for_free_list (hdr_b0, fl);
 241
 242               memcpy (hdr_b0->data, ip0, sizeof (*ip0));
 243               memcpy (hdr_b0->data + sizeof (*ip0), t0->rewrite,
 244                       vec_len (t0->rewrite));
 245
 246               hdr_b0->current_data = 0;
 247               hdr_b0->current_length = sizeof (*ip0) + vec_len (t0->rewrite);
 248               hdr_b0->flags = orig_b0->flags | VLIB_BUFFER_NEXT_PRESENT;
 249
 250
 251               hdr_b0->total_length_not_including_first_buffer =
 252                 hdr_mb0->pkt_len - hdr_b0->current_length;
 253
 254               hdr_ip0 = (ip6_header_t *) hdr_b0->data;
 255               hdr_ip0->payload_length = clib_host_to_net_u16(hdr_mb0->data_len);
 256               hdr_sr0 = (ip6_sr_header_t *) (hdr_ip0+1);
 257               hdr_sr0->protocol = hdr_ip0->protocol;
 258               hdr_ip0->protocol = 43;
 259
 260               /* Rewrite the ip6 dst address */
 261               hdr_ip0->dst_address.as_u64[0] = t0->first_hop.as_u64[0];
 262               hdr_ip0->dst_address.as_u64[1] = t0->first_hop.as_u64[1];
 263
 264               sr_fix_hmac (sm, hdr_ip0, hdr_sr0);
 265
 266               /* prepend new header to invariant piece */
 267               hdr_mb0->next = clone0;
 268               hdr_b0->next_buffer = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (clone0));
 269
 270               /* update header's fields */
 271               hdr_mb0->pkt_len = (uint16_t)(hdr_mb0->data_len + clone0->pkt_len);
 272               hdr_mb0->nb_segs = (uint8_t)(clone0->nb_segs + 1);
 273
 274               /* copy metadata from source packet*/
 275               hdr_mb0->port = clone0->port;
 276               hdr_mb0->vlan_tci = clone0->vlan_tci;
 277               hdr_mb0->vlan_tci_outer = clone0->vlan_tci_outer;
 278               hdr_mb0->tx_offload = clone0->tx_offload;
 279               hdr_mb0->hash = clone0->hash;
 280
 281               hdr_mb0->ol_flags = clone0->ol_flags;
 282
 283               __rte_mbuf_sanity_check(hdr_mb0, 1);
 284
 285               hdr_bi0 = vlib_get_buffer_index (vm, hdr_b0);
 286
 287               to_next[0] = hdr_bi0;
 288               to_next += 1;
 289               n_left_to_next -= 1;
 290
 291               if (n_left_to_next == 0)
 292                 {
 293                   vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 294                   vlib_get_next_frame (vm, node, next_index,
 295                                        to_next, n_left_to_next);
 296
 297                 }
 298               pkts_replicated++;
 299             }
 300
 301           from += 1;
 302           n_left_from -= 1;
 303
 304         do_trace0:
 305           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 306             {
 307               sr_replicate_trace_t *tr = vlib_add_trace (vm, node,
 308                                                        b0, sizeof (*tr));
 309               tr->tunnel_index = t0 - sm->tunnels;
 310               if (hdr_ip0)
 311                 {
 312                   memcpy (tr->src.as_u8, hdr_ip0->src_address.as_u8,
 313                       sizeof (tr->src.as_u8));
 314                   memcpy (tr->dst.as_u8, hdr_ip0->dst_address.as_u8,
 315                       sizeof (tr->dst.as_u8));
 316                 }
 317               if (hdr_ip0->payload_length)
 318                 tr->length = clib_net_to_host_u16(hdr_ip0->payload_length);
 319               else
 320                 tr->length = 0;
 321               tr->next_index = next_index;
 322               memcpy (tr->sr, hdr_sr0, sizeof (tr->sr));
 323             }
 324
 325         }
 326
 327       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 328     }
 329
 330   vlib_node_increment_counter (vm, sr_replicate_node.index,
 331                                SR_REPLICATE_ERROR_REPLICATED, pkts_replicated);
 332
 333   vlib_node_increment_counter (vm, sr_replicate_node.index,
 334                                SR_REPLICATE_ERROR_NO_BUFFER_DROPS, no_buffer_drops);
 335
 336   return frame->n_vectors;
 337 }
 338
 339 VLIB_REGISTER_NODE (sr_replicate_node) = {
 340   .function = sr_replicate_node_fn,
 341   .name = "sr-replicate",
 342   .vector_size = sizeof (u32),
 343   .format_trace = format_sr_replicate_trace,
 344   .type = VLIB_NODE_TYPE_INTERNAL,
 345
 346   .n_errors = ARRAY_LEN(sr_replicate_error_strings),
 347   .error_strings = sr_replicate_error_strings,
 348
 349   .n_next_nodes = SR_REPLICATE_N_NEXT,
 350
 351   .next_nodes = {
 352         [SR_REPLICATE_NEXT_IP6_LOOKUP] = "ip6-lookup",
 353   },
 354 };
 355
 356 clib_error_t *sr_replicate_init (vlib_main_t *vm)
 357 {
 358   sr_replicate_main_t *msm = &sr_replicate_main;
 359
 360   msm->vlib_main = vm;
 361   msm->vnet_main = vnet_get_main();
 362
 363   return 0;
 364 }
 365
 366 VLIB_INIT_FUNCTION(sr_replicate_init);