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 #if DPDK > 0 /* Cannot run replicate without DPDK */
  19 #include <vlib/vlib.h>
  20 #include <vnet/vnet.h>
  21 #include <vnet/pg/pg.h>
  22 #include <vnet/sr/sr.h>
  23 #include <vnet/devices/dpdk/dpdk.h>
  24 #include <vnet/dpdk_replication.h>
  25 #include <vnet/ip/ip.h>
  26
  27 #include <vppinfra/hash.h>
  28 #include <vppinfra/error.h>
  29 #include <vppinfra/elog.h>
  30
  31 typedef struct {
  32   /* convenience */
  33   vlib_main_t * vlib_main;
  34   vnet_main_t * vnet_main;
  35 } sr_replicate_main_t;
  36
  37 sr_replicate_main_t sr_replicate_main;
  38
  39 vlib_node_registration_t sr_replicate_node;
  40
  41
  42 typedef struct {
  43   ip6_address_t src, dst;
  44   u16 length;
  45   u32 next_index;
  46   u32 tunnel_index;
  47   u8 sr[256];
  48 } sr_replicate_trace_t;
  49
  50 /* packet trace format function */
  51 static u8 * format_sr_replicate_trace (u8 * s, va_list * args)
  52 {
  53   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  54   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  55   sr_replicate_trace_t * t = va_arg (*args, sr_replicate_trace_t *);
  56   ip6_main_t * im = &ip6_main;
  57   ip6_sr_main_t * sm = &sr_main;
  58   ip6_sr_tunnel_t *tun = pool_elt_at_index (sm->tunnels, t->tunnel_index);
  59   ip6_fib_t * rx_fib, * tx_fib;
  60
  61   rx_fib = find_ip6_fib_by_table_index_or_id (im, tun->rx_fib_index,
  62                                               IP6_ROUTE_FLAG_FIB_INDEX);
  63
  64   tx_fib = find_ip6_fib_by_table_index_or_id (im, tun->tx_fib_index,
  65                                               IP6_ROUTE_FLAG_FIB_INDEX);
  66
  67   s = format
  68     (s, "SR-REPLICATE: next %s ip6 src %U dst %U len %u\n"
  69      "           rx-fib-id %d tx-fib-id %d\n%U",
  70      "ip6-lookup",
  71      format_ip6_address, &t->src,
  72      format_ip6_address, &t->dst, t->length,
  73      rx_fib->table_id, tx_fib->table_id,
  74      format_ip6_sr_header, t->sr, 0 /* print_hmac */);
  75   return s;
  76
  77 }
  78
  79 vlib_node_registration_t sr_replicate_node;
  80
  81 #define foreach_sr_replicate_error \
  82 _(REPLICATED, "sr packets replicated") \
  83 _(NO_BUFFERS, "error allocating buffers for replicas") \
  84 _(NO_REPLICAS, "no replicas were needed") \
  85 _(NO_BUFFER_DROPS, "sr no buffer drops")
  86
  87 typedef enum {
  88 #define _(sym,str) SR_REPLICATE_ERROR_##sym,
  89   foreach_sr_replicate_error
  90 #undef _
  91   SR_REPLICATE_N_ERROR,
  92 } sr_replicate_error_t;
  93
  94 static char * sr_replicate_error_strings[] = {
  95 #define _(sym,string) string,
  96   foreach_sr_replicate_error
  97 #undef _
  98 };
  99
 100 typedef enum {
 101   SR_REPLICATE_NEXT_IP6_LOOKUP,
 102   SR_REPLICATE_N_NEXT,
 103 } sr_replicate_next_t;
 104
 105 static uword
 106 sr_replicate_node_fn (vlib_main_t * vm,
 107                   vlib_node_runtime_t * node,
 108                   vlib_frame_t * frame)
 109 {
 110   u32 n_left_from, * from, * to_next;
 111   sr_replicate_next_t next_index;
 112   int pkts_replicated = 0;
 113   ip6_sr_main_t * sm = &sr_main;
 114   int no_buffer_drops = 0;
 115   vlib_buffer_free_list_t * fl;
 116   unsigned socket_id = rte_socket_id();
 117   vlib_buffer_main_t * bm = vm->buffer_main;
 118
 119   from = vlib_frame_vector_args (frame);
 120   n_left_from = frame->n_vectors;
 121   next_index = node->cached_next_index;
 122
 123   fl = vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
 124
 125   while (n_left_from > 0)
 126     {
 127       u32 n_left_to_next;
 128
 129       vlib_get_next_frame (vm, node, next_index,
 130                            to_next, n_left_to_next);
 131
 132       while (n_left_from > 0 && n_left_to_next > 0)
 133         {
 134           u32 bi0, hdr_bi0;
 135           vlib_buffer_t * b0, * orig_b0;
 136           struct rte_mbuf * orig_mb0 = 0, * hdr_mb0 = 0, * clone0 = 0;
 137           struct rte_mbuf ** hdr_vec = 0, ** rte_mbuf_vec = 0;
 138           ip6_sr_policy_t * pol0 = 0;
 139           ip6_sr_tunnel_t * t0 = 0;
 140           ip6_sr_header_t * hdr_sr0 = 0;
 141           ip6_header_t * ip0 = 0, * hdr_ip0 = 0;
 142           int num_replicas = 0;
 143           int i;
 144
 145           bi0 = from[0];
 146
 147           b0 = vlib_get_buffer (vm, bi0);
 148           orig_b0 = b0;
 149
 150           pol0 = pool_elt_at_index (sm->policies,
 151                                     vnet_buffer(b0)->ip.save_protocol);
 152
 153           ip0 = vlib_buffer_get_current (b0);
 154           /* Skip forward to the punch-in point */
 155           vlib_buffer_advance (b0, sizeof(*ip0));
 156
 157           orig_mb0 = rte_mbuf_from_vlib_buffer (b0);
 158
 159           i16 delta0 = vlib_buffer_length_in_chain (vm, orig_b0)
 160             - (i16) orig_mb0->pkt_len;
 161
 162           u16 new_data_len0 = (u16)((i16) orig_mb0->data_len + delta0);
 163           u16 new_pkt_len0  = (u16)((i16) orig_mb0->pkt_len + delta0);
 164
 165           orig_mb0->data_len = new_data_len0;
 166           orig_mb0->pkt_len = new_pkt_len0;
 167           orig_mb0->data_off = (u16)(RTE_PKTMBUF_HEADROOM + b0->current_data);
 168
 169           /*
 170             Before entering loop determine if we can allocate:
 171             - all the new HEADER RTE_MBUFs and assign them to a vector
 172             - all the clones
 173
 174             if successful, then iterate over vectors of resources
 175
 176            */
 177           num_replicas = vec_len (pol0->tunnel_indices);
 178
 179           if (PREDICT_FALSE(num_replicas == 0))
 180             {
 181               b0->error = node->errors[SR_REPLICATE_ERROR_NO_REPLICAS];
 182               goto do_trace0;
 183             }
 184
 185           vec_reset_length (hdr_vec);
 186           vec_reset_length (rte_mbuf_vec);
 187
 188           for (i=0; i < num_replicas; i++)
 189             {
 190               hdr_mb0 = rte_pktmbuf_alloc(bm->pktmbuf_pools[socket_id]);
 191
 192               if (i < (num_replicas - 1) )
 193                 /* Not the last tunnel to process */
 194                 clone0 = rte_pktmbuf_clone
 195                     (orig_mb0, bm->pktmbuf_pools[socket_id]);
 196               else
 197                   /* Last tunnel to process, use original MB */
 198                 clone0 = orig_mb0;
 199
 200
 201               if (PREDICT_FALSE( !clone0 || !hdr_mb0 ))
 202                 {
 203                   b0->error = node->errors[SR_REPLICATE_ERROR_NO_BUFFERS];
 204
 205                   vec_foreach_index (i, rte_mbuf_vec)
 206                     {
 207                       rte_pktmbuf_free(rte_mbuf_vec[i]);
 208                     }
 209                   vec_free (rte_mbuf_vec);
 210
 211                   vec_foreach_index (i, hdr_vec)
 212                     {
 213                       rte_pktmbuf_free(hdr_vec[i]);
 214                     }
 215                   vec_free (hdr_vec);
 216
 217                   goto do_trace0;
 218                 }
 219
 220               vec_add1 (hdr_vec, hdr_mb0);
 221               vec_add1 (rte_mbuf_vec, clone0);
 222
 223             }
 224
 225           for (i=0; i < num_replicas; i++)
 226             {
 227               vlib_buffer_t * hdr_b0;
 228
 229               t0 = vec_elt_at_index (sm->tunnels, pol0->tunnel_indices[i]);
 230
 231               /* Our replicas */
 232               hdr_mb0 = hdr_vec[i];
 233               clone0 = rte_mbuf_vec[i];
 234
 235               hdr_mb0->data_len = sizeof (*ip0) + vec_len (t0->rewrite);
 236               hdr_mb0->pkt_len = hdr_mb0->data_len +
 237                   vlib_buffer_length_in_chain (vm, orig_b0);
 238
 239               hdr_b0 = vlib_buffer_from_rte_mbuf (hdr_mb0);
 240
 241               vlib_buffer_init_for_free_list (hdr_b0, fl);
 242
 243               memcpy (hdr_b0->data, ip0, sizeof (*ip0));
 244               memcpy (hdr_b0->data + sizeof (*ip0), t0->rewrite,
 245                       vec_len (t0->rewrite));
 246
 247               hdr_b0->current_data = 0;
 248               hdr_b0->current_length = sizeof (*ip0) + vec_len (t0->rewrite);
 249               hdr_b0->flags = orig_b0->flags | VLIB_BUFFER_NEXT_PRESENT;
 250
 251
 252               hdr_b0->total_length_not_including_first_buffer =
 253                 hdr_mb0->pkt_len - hdr_b0->current_length;
 254
 255               hdr_ip0 = (ip6_header_t *) hdr_b0->data;
 256               hdr_ip0->payload_length = clib_host_to_net_u16(hdr_mb0->data_len);
 257               hdr_sr0 = (ip6_sr_header_t *) (hdr_ip0+1);
 258               hdr_sr0->protocol = hdr_ip0->protocol;
 259               hdr_ip0->protocol = 43;
 260
 261               /* Rewrite the ip6 dst address */
 262               hdr_ip0->dst_address.as_u64[0] = t0->first_hop.as_u64[0];
 263               hdr_ip0->dst_address.as_u64[1] = t0->first_hop.as_u64[1];
 264
 265               sr_fix_hmac (sm, hdr_ip0, hdr_sr0);
 266
 267               /* prepend new header to invariant piece */
 268               hdr_mb0->next = clone0;
 269               hdr_b0->next_buffer = vlib_get_buffer_index (vm, vlib_buffer_from_rte_mbuf (clone0));
 270
 271               /* update header's fields */
 272               hdr_mb0->pkt_len = (uint16_t)(hdr_mb0->data_len + clone0->pkt_len);
 273               hdr_mb0->nb_segs = (uint8_t)(clone0->nb_segs + 1);
 274
 275               /* copy metadata from source packet*/
 276               hdr_mb0->port = clone0->port;
 277               hdr_mb0->vlan_tci = clone0->vlan_tci;
 278               hdr_mb0->vlan_tci_outer = clone0->vlan_tci_outer;
 279               hdr_mb0->tx_offload = clone0->tx_offload;
 280               hdr_mb0->hash = clone0->hash;
 281
 282               hdr_mb0->ol_flags = clone0->ol_flags;
 283
 284               __rte_mbuf_sanity_check(hdr_mb0, 1);
 285
 286               hdr_bi0 = vlib_get_buffer_index (vm, hdr_b0);
 287
 288               to_next[0] = hdr_bi0;
 289               to_next += 1;
 290               n_left_to_next -= 1;
 291
 292               if (n_left_to_next == 0)
 293                 {
 294                   vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 295                   vlib_get_next_frame (vm, node, next_index,
 296                                        to_next, n_left_to_next);
 297
 298                 }
 299               pkts_replicated++;
 300             }
 301
 302           from += 1;
 303           n_left_from -= 1;
 304
 305         do_trace0:
 306           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 307             {
 308               sr_replicate_trace_t *tr = vlib_add_trace (vm, node,
 309                                                        b0, sizeof (*tr));
 310               tr->tunnel_index = t0 - sm->tunnels;
 311               if (hdr_ip0)
 312                 {
 313                   memcpy (tr->src.as_u8, hdr_ip0->src_address.as_u8,
 314                       sizeof (tr->src.as_u8));
 315                   memcpy (tr->dst.as_u8, hdr_ip0->dst_address.as_u8,
 316                       sizeof (tr->dst.as_u8));
 317                 }
 318               if (hdr_ip0->payload_length)
 319                 tr->length = clib_net_to_host_u16(hdr_ip0->payload_length);
 320               else
 321                 tr->length = 0;
 322               tr->next_index = next_index;
 323               memcpy (tr->sr, hdr_sr0, sizeof (tr->sr));
 324             }
 325
 326         }
 327
 328       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 329     }
 330
 331   vlib_node_increment_counter (vm, sr_replicate_node.index,
 332                                SR_REPLICATE_ERROR_REPLICATED, pkts_replicated);
 333
 334   vlib_node_increment_counter (vm, sr_replicate_node.index,
 335                                SR_REPLICATE_ERROR_NO_BUFFER_DROPS, no_buffer_drops);
 336
 337   return frame->n_vectors;
 338 }
 339
 340 VLIB_REGISTER_NODE (sr_replicate_node) = {
 341   .function = sr_replicate_node_fn,
 342   .name = "sr-replicate",
 343   .vector_size = sizeof (u32),
 344   .format_trace = format_sr_replicate_trace,
 345   .type = VLIB_NODE_TYPE_INTERNAL,
 346
 347   .n_errors = ARRAY_LEN(sr_replicate_error_strings),
 348   .error_strings = sr_replicate_error_strings,
 349
 350   .n_next_nodes = SR_REPLICATE_N_NEXT,
 351
 352   .next_nodes = {
 353         [SR_REPLICATE_NEXT_IP6_LOOKUP] = "ip6-lookup",
 354   },
 355 };
 356
 357 clib_error_t *sr_replicate_init (vlib_main_t *vm)
 358 {
 359   sr_replicate_main_t *msm = &sr_replicate_main;
 360
 361   msm->vlib_main = vm;
 362   msm->vnet_main = vnet_get_main();
 363
 364   return 0;
 365 }
 366
 367 VLIB_INIT_FUNCTION(sr_replicate_init);
 368
 369 #endif /* DPDK */