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