vnet/vnet/l2/l2_input_vtr.c

   1 /*
   2  * l2_input_vtr.c : layer 2 input vlan tag rewrite processing
   3  *
   4  * Copyright (c) 2013 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/ethernet/ethernet.h>
  21 #include <vnet/ethernet/packet.h>
  22 #include <vnet/l2/l2_input.h>
  23 #include <vnet/l2/feat_bitmap.h>
  24 #include <vnet/l2/l2_vtr.h>
  25 #include <vnet/l2/l2_input_vtr.h>
  26 #include <vnet/l2/l2_output.h>
  27
  28 #include <vppinfra/error.h>
  29 #include <vppinfra/cache.h>
  30
  31
  32 typedef struct {
  33   /* per-pkt trace data */
  34   u8  src[6];
  35   u8  dst[6];
  36   u8  raw[12]; // raw data (vlans)
  37   u32 sw_if_index;
  38 } l2_invtr_trace_t;
  39
  40 /* packet trace format function */
  41 static u8 * format_l2_invtr_trace (u8 * s, va_list * args)
  42 {
  43   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  44   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  45   l2_invtr_trace_t * t = va_arg (*args, l2_invtr_trace_t *);
  46
  47   s = format (s, "l2-input-vtr: sw_if_index %d dst %U src %U data "
  48               "%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
  49               t->sw_if_index,
  50               format_ethernet_address, t->dst,
  51               format_ethernet_address, t->src,
  52               t->raw[0], t->raw[1], t->raw[2], t->raw[3], t->raw[4], t->raw[5],
  53               t->raw[6], t->raw[7], t->raw[8], t->raw[9], t->raw[10], t->raw[11]);
  54   return s;
  55 }
  56
  57 l2_invtr_main_t l2_invtr_main;
  58
  59 static vlib_node_registration_t l2_invtr_node;
  60
  61 #define foreach_l2_invtr_error                  \
  62 _(L2_INVTR,    "L2 inverter packets")           \
  63 _(DROP,        "L2 input tag rewrite drops")
  64
  65 typedef enum {
  66 #define _(sym,str) L2_INVTR_ERROR_##sym,
  67   foreach_l2_invtr_error
  68 #undef _
  69   L2_INVTR_N_ERROR,
  70 } l2_invtr_error_t;
  71
  72 static char * l2_invtr_error_strings[] = {
  73 #define _(sym,string) string,
  74   foreach_l2_invtr_error
  75 #undef _
  76 };
  77
  78 typedef enum {
  79   L2_INVTR_NEXT_DROP,
  80   L2_INVTR_N_NEXT,
  81 } l2_invtr_next_t;
  82
  83
  84 static uword
  85 l2_invtr_node_fn (vlib_main_t * vm,
  86                   vlib_node_runtime_t * node,
  87                   vlib_frame_t * frame)
  88 {
  89   u32 n_left_from, * from, * to_next;
  90   l2_invtr_next_t next_index;
  91   l2_invtr_main_t * msm = &l2_invtr_main;
  92   // vlib_node_t *n = vlib_get_node (vm, l2_invtr_node.index);
  93   // u32 node_counter_base_index = n->error_heap_index;
  94   // vlib_error_main_t * em = &vm->error_main;
  95
  96   from = vlib_frame_vector_args (frame);
  97   n_left_from = frame->n_vectors; /* number of packets to process */
  98   next_index = node->cached_next_index;
  99
 100   while (n_left_from > 0)
 101     {
 102       u32 n_left_to_next;
 103
 104       /* get space to enqueue frame to graph node "next_index" */
 105       vlib_get_next_frame (vm, node, next_index,
 106                            to_next, n_left_to_next);
 107
 108       while (n_left_from >= 6 && n_left_to_next >= 2)
 109         {
 110           u32 bi0, bi1;
 111           vlib_buffer_t * b0, * b1;
 112           u32 next0, next1;
 113           u32 sw_if_index0, sw_if_index1;
 114           u32 feature_bitmap0, feature_bitmap1;
 115
 116           /* Prefetch next iteration. */
 117           {
 118             vlib_buffer_t * p2, * p3, * p4, * p5;
 119             u32 sw_if_index2, sw_if_index3;
 120
 121             p2 = vlib_get_buffer (vm, from[2]);
 122             p3 = vlib_get_buffer (vm, from[3]);
 123             p4 = vlib_get_buffer (vm, from[4]);
 124             p5 = vlib_get_buffer (vm, from[5]);
 125
 126             // Prefetch the buffer header and packet for the N+2 loop iteration
 127             vlib_prefetch_buffer_header (p4, LOAD);
 128             vlib_prefetch_buffer_header (p5, LOAD);
 129
 130             CLIB_PREFETCH (p4->data, CLIB_CACHE_LINE_BYTES, STORE);
 131             CLIB_PREFETCH (p5->data, CLIB_CACHE_LINE_BYTES, STORE);
 132
 133             // Prefetch the input config for the N+1 loop iteration
 134             // This depends on the buffer header above
 135             sw_if_index2 = vnet_buffer(p2)->sw_if_index[VLIB_RX];
 136             sw_if_index3 = vnet_buffer(p3)->sw_if_index[VLIB_RX];
 137             CLIB_PREFETCH (vec_elt_at_index(l2output_main.configs, sw_if_index2), CLIB_CACHE_LINE_BYTES, LOAD);
 138             CLIB_PREFETCH (vec_elt_at_index(l2output_main.configs, sw_if_index3), CLIB_CACHE_LINE_BYTES, LOAD);
 139           }
 140
 141           /* speculatively enqueue b0 and b1 to the current next frame */
 142           /* bi is "buffer index", b is pointer to the buffer */
 143           to_next[0] = bi0 = from[0];
 144           to_next[1] = bi1 = from[1];
 145           from += 2;
 146           to_next += 2;
 147           n_left_from -= 2;
 148           n_left_to_next -= 2;
 149
 150           b0 = vlib_get_buffer (vm, bi0);
 151           b1 = vlib_get_buffer (vm, bi1);
 152
 153           /* RX interface handles */
 154           sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
 155           sw_if_index1 = vnet_buffer(b1)->sw_if_index[VLIB_RX];
 156
 157           // process 2 packets
 158           // em->counters[node_counter_base_index + L2_INVTR_ERROR_L2_INVTR] += 2;
 159
 160           // Remove ourself from the feature bitmap
 161           feature_bitmap0 = vnet_buffer(b0)->l2.feature_bitmap & ~L2INPUT_FEAT_VTR;
 162           feature_bitmap1 = vnet_buffer(b1)->l2.feature_bitmap & ~L2INPUT_FEAT_VTR;
 163
 164           // save for next feature graph nodes
 165           vnet_buffer(b0)->l2.feature_bitmap = feature_bitmap0;
 166           vnet_buffer(b1)->l2.feature_bitmap = feature_bitmap1;
 167
 168           // Determine the next node
 169           next0 = feat_bitmap_get_next_node_index(msm->feat_next_node_index,
 170                                                   feature_bitmap0);
 171           next1 = feat_bitmap_get_next_node_index(msm->feat_next_node_index,
 172                                                   feature_bitmap1);
 173
 174           // perform the tag rewrite on two packets
 175           if (l2_vtr_process(b0, &(vec_elt_at_index(l2output_main.configs, sw_if_index0)->input_vtr))) {
 176             // Drop packet
 177             next0 = L2_INVTR_NEXT_DROP;
 178             b0->error = node->errors[L2_INVTR_ERROR_DROP];
 179           }
 180           if (l2_vtr_process(b1, &(vec_elt_at_index(l2output_main.configs, sw_if_index1)->input_vtr))) {
 181             // Drop packet
 182             next1 = L2_INVTR_NEXT_DROP;
 183             b1->error = node->errors[L2_INVTR_ERROR_DROP];
 184           }
 185
 186           if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE))) {
 187             if (b0->flags & VLIB_BUFFER_IS_TRACED) {
 188               l2_invtr_trace_t *t =
 189                vlib_add_trace (vm, node, b0, sizeof (*t));
 190               ethernet_header_t * h0 = vlib_buffer_get_current (b0);
 191               t->sw_if_index = sw_if_index0;
 192               memcpy(t->src, h0->src_address, 6);
 193               memcpy(t->dst, h0->dst_address, 6);
 194               memcpy(t->raw, &h0->type, sizeof(t->raw));
 195             }
 196             if (b1->flags & VLIB_BUFFER_IS_TRACED) {
 197               l2_invtr_trace_t *t =
 198                vlib_add_trace (vm, node, b1, sizeof (*t));
 199               ethernet_header_t * h1 = vlib_buffer_get_current (b1);
 200               t->sw_if_index = sw_if_index0;
 201               memcpy(t->src, h1->src_address, 6);
 202               memcpy(t->dst, h1->dst_address, 6);
 203               memcpy(t->raw, &h1->type, sizeof(t->raw));
 204             }
 205           }
 206
 207           /* verify speculative enqueues, maybe switch current next frame */
 208           /* if next0==next1==next_index then nothing special needs to be done */
 209           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
 210                                            to_next, n_left_to_next,
 211                                            bi0, bi1, next0, next1);
 212         }
 213
 214       while (n_left_from > 0 && n_left_to_next > 0)
 215         {
 216           u32 bi0;
 217           vlib_buffer_t * b0;
 218           u32 next0;
 219           u32 sw_if_index0;
 220           u32 feature_bitmap0;
 221
 222           /* speculatively enqueue b0 to the current next frame */
 223           bi0 = from[0];
 224           to_next[0] = bi0;
 225           from += 1;
 226           to_next += 1;
 227           n_left_from -= 1;
 228           n_left_to_next -= 1;
 229
 230           b0 = vlib_get_buffer (vm, bi0);
 231
 232           sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
 233
 234           // process 1 packet
 235           // em->counters[node_counter_base_index + L2_INVTR_ERROR_L2_INVTR] += 1;
 236
 237           // Remove ourself from the feature bitmap
 238           feature_bitmap0 = vnet_buffer(b0)->l2.feature_bitmap & ~L2INPUT_FEAT_VTR;
 239
 240           // save for next feature graph nodes
 241           vnet_buffer(b0)->l2.feature_bitmap = feature_bitmap0;
 242
 243           // Determine the next node
 244           next0 = feat_bitmap_get_next_node_index(msm->feat_next_node_index,
 245                                                   feature_bitmap0);
 246
 247           // perform the tag rewrite on one packet
 248           if (l2_vtr_process(b0, &(vec_elt_at_index(l2output_main.configs, sw_if_index0)->input_vtr))) {
 249             // Drop packet
 250             next0 = L2_INVTR_NEXT_DROP;
 251             b0->error = node->errors[L2_INVTR_ERROR_DROP];
 252           }
 253
 254           if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE)
 255                             && (b0->flags & VLIB_BUFFER_IS_TRACED))) {
 256             l2_invtr_trace_t *t =
 257                vlib_add_trace (vm, node, b0, sizeof (*t));
 258             ethernet_header_t * h0 = vlib_buffer_get_current (b0);
 259             t->sw_if_index = sw_if_index0;
 260             memcpy(t->src, h0->src_address, 6);
 261             memcpy(t->dst, h0->dst_address, 6);
 262             memcpy(t->raw, &h0->type, sizeof(t->raw));
 263           }
 264
 265           /* verify speculative enqueue, maybe switch current next frame */
 266           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 267                                            to_next, n_left_to_next,
 268                                            bi0, next0);
 269         }
 270
 271       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 272     }
 273
 274   return frame->n_vectors;
 275 }
 276
 277
 278 VLIB_REGISTER_NODE (l2_invtr_node,static) = {
 279   .function = l2_invtr_node_fn,
 280   .name = "l2-input-vtr",
 281   .vector_size = sizeof (u32),
 282   .format_trace = format_l2_invtr_trace,
 283   .type = VLIB_NODE_TYPE_INTERNAL,
 284
 285   .n_errors = ARRAY_LEN(l2_invtr_error_strings),
 286   .error_strings = l2_invtr_error_strings,
 287
 288   .n_next_nodes = L2_INVTR_N_NEXT,
 289
 290   /* edit / add dispositions here */
 291   .next_nodes = {
 292        [L2_INVTR_NEXT_DROP]  = "error-drop",
 293   },
 294 };
 295
 296 clib_error_t *l2_invtr_init (vlib_main_t *vm)
 297 {
 298   l2_invtr_main_t * mp = &l2_invtr_main;
 299
 300   mp->vlib_main = vm;
 301   mp->vnet_main = vnet_get_main();
 302
 303   // Initialize the feature next-node indexes
 304   feat_bitmap_init_next_nodes(vm,
 305                               l2_invtr_node.index,
 306                               L2INPUT_N_FEAT,
 307                               l2input_get_feat_names(),
 308                               mp->feat_next_node_index);
 309
 310   return 0;
 311 }
 312
 313 VLIB_INIT_FUNCTION (l2_invtr_init);
 314