2 * l2_output.c : layer 2 output packet processing
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:
9 * http://www.apache.org/licenses/LICENSE-2.0
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.
18 #include <vlib/vlib.h>
19 #include <vnet/vnet.h>
20 #include <vnet/pg/pg.h>
21 #include <vnet/ethernet/ethernet.h>
24 #include <vppinfra/error.h>
25 #include <vppinfra/hash.h>
26 #include <vnet/l2/feat_bitmap.h>
27 #include <vnet/l2/l2_output.h>
30 /* Feature graph node names */
31 static char *l2output_feat_names[] = {
32 #define _(sym,name) name,
38 l2output_get_feat_names (void)
40 return l2output_feat_names;
43 l2output_main_t l2output_main;
47 /* per-pkt trace data */
53 /* packet trace format function */
55 format_l2output_trace (u8 * s, va_list * args)
57 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
58 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
59 l2output_trace_t *t = va_arg (*args, l2output_trace_t *);
61 s = format (s, "l2-output: sw_if_index %d dst %U src %U",
63 format_ethernet_address, t->dst,
64 format_ethernet_address, t->src);
69 static char *l2output_error_strings[] = {
70 #define _(sym,string) string,
71 foreach_l2output_error
76 * Check for split horizon violations.
77 * Return 0 if split horizon check passes, otherwise return non-zero.
78 * Packets should not be transmitted out an interface with the same
79 * split-horizon group as the input interface, except if the @c shg is 0
80 * in which case the check always passes.
82 static_always_inline u32
83 split_horizon_violation (u8 shg1, u8 shg2)
85 if (PREDICT_TRUE (shg1 == 0))
95 static_always_inline void
96 l2output_vtr (vlib_node_runtime_t * node, l2_output_config_t * config,
97 u32 feature_bitmap, vlib_buffer_t * b, u32 * next)
99 if (PREDICT_FALSE (config->out_vtr_flag))
101 /* Perform pre-vtr EFP filter check if configured */
102 if (config->output_vtr.push_and_pop_bytes)
105 * Perform output vlan tag rewrite and the pre-vtr EFP filter check.
106 * The EFP Filter only needs to be run if there is an output VTR
107 * configured. The flag for the post-vtr EFP Filter node is used
108 * to trigger the pre-vtr check as well.
110 u32 failed1 = (feature_bitmap & L2OUTPUT_FEAT_EFP_FILTER)
111 && (l2_efp_filter_process (b, &(config->input_vtr)));
112 u32 failed2 = l2_vtr_process (b, &(config->output_vtr));
114 if (PREDICT_FALSE (failed1 | failed2))
116 *next = L2OUTPUT_NEXT_DROP;
119 b->error = node->errors[L2OUTPUT_ERROR_VTR_DROP];
123 b->error = node->errors[L2OUTPUT_ERROR_EFP_DROP];
127 // perform the PBB rewrite
128 else if (config->output_pbb_vtr.push_and_pop_bytes)
130 u32 failed = l2_pbb_process (b, &(config->output_pbb_vtr));
131 if (PREDICT_FALSE (failed))
133 *next = L2OUTPUT_NEXT_DROP;
134 b->error = node->errors[L2OUTPUT_ERROR_VTR_DROP];
141 static vlib_node_registration_t l2output_node;
144 l2output_node_fn (vlib_main_t * vm,
145 vlib_node_runtime_t * node, vlib_frame_t * frame)
147 u32 n_left_from, *from, *to_next;
148 l2output_next_t next_index;
149 l2output_main_t *msm = &l2output_main;
150 u32 cached_sw_if_index;
151 u32 cached_next_index;
153 /* Invalidate cache */
154 cached_sw_if_index = ~0;
155 cached_next_index = ~0; /* warning be gone */
157 from = vlib_frame_vector_args (frame);
158 n_left_from = frame->n_vectors; /* number of packets to process */
159 next_index = node->cached_next_index;
161 while (n_left_from > 0)
165 /* get space to enqueue frame to graph node "next_index" */
166 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
168 while (n_left_from >= 8 && n_left_to_next >= 4)
170 u32 bi0, bi1, bi2, bi3;
171 vlib_buffer_t *b0, *b1, *b2, *b3;
172 u32 next0, next1, next2, next3;
173 u32 sw_if_index0, sw_if_index1, sw_if_index2, sw_if_index3;
174 ethernet_header_t *h0, *h1, *h2, *h3;
175 l2_output_config_t *config0, *config1, *config2, *config3;
176 u32 feature_bitmap0, feature_bitmap1;
177 u32 feature_bitmap2, feature_bitmap3;
179 /* Prefetch next iteration. */
181 vlib_buffer_t *p4, *p5, *p6, *p7;
183 p4 = vlib_get_buffer (vm, from[4]);
184 p5 = vlib_get_buffer (vm, from[5]);
185 p6 = vlib_get_buffer (vm, from[6]);
186 p7 = vlib_get_buffer (vm, from[7]);
188 /* Prefetch the buffer header for the N+2 loop iteration */
189 vlib_prefetch_buffer_header (p4, LOAD);
190 vlib_prefetch_buffer_header (p5, LOAD);
191 vlib_prefetch_buffer_header (p6, LOAD);
192 vlib_prefetch_buffer_header (p7, LOAD);
195 /* speculatively enqueue b0 and b1 to the current next frame */
196 /* bi is "buffer index", b is pointer to the buffer */
197 to_next[0] = bi0 = from[0];
198 to_next[1] = bi1 = from[1];
199 to_next[2] = bi2 = from[2];
200 to_next[3] = bi3 = from[3];
206 b0 = vlib_get_buffer (vm, bi0);
207 b1 = vlib_get_buffer (vm, bi1);
208 b2 = vlib_get_buffer (vm, bi2);
209 b3 = vlib_get_buffer (vm, bi3);
211 /* TX interface handles */
212 sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
213 sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_TX];
214 sw_if_index2 = vnet_buffer (b2)->sw_if_index[VLIB_TX];
215 sw_if_index3 = vnet_buffer (b3)->sw_if_index[VLIB_TX];
217 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
219 h0 = vlib_buffer_get_current (b0);
220 h1 = vlib_buffer_get_current (b1);
221 h2 = vlib_buffer_get_current (b2);
222 h3 = vlib_buffer_get_current (b3);
223 if (b0->flags & VLIB_BUFFER_IS_TRACED)
225 l2output_trace_t *t =
226 vlib_add_trace (vm, node, b0, sizeof (*t));
227 t->sw_if_index = sw_if_index0;
228 clib_memcpy (t->src, h0->src_address, 6);
229 clib_memcpy (t->dst, h0->dst_address, 6);
231 if (b1->flags & VLIB_BUFFER_IS_TRACED)
233 l2output_trace_t *t =
234 vlib_add_trace (vm, node, b1, sizeof (*t));
235 t->sw_if_index = sw_if_index1;
236 clib_memcpy (t->src, h1->src_address, 6);
237 clib_memcpy (t->dst, h1->dst_address, 6);
239 if (b2->flags & VLIB_BUFFER_IS_TRACED)
241 l2output_trace_t *t =
242 vlib_add_trace (vm, node, b2, sizeof (*t));
243 t->sw_if_index = sw_if_index2;
244 clib_memcpy (t->src, h2->src_address, 6);
245 clib_memcpy (t->dst, h2->dst_address, 6);
247 if (b3->flags & VLIB_BUFFER_IS_TRACED)
249 l2output_trace_t *t =
250 vlib_add_trace (vm, node, b3, sizeof (*t));
251 t->sw_if_index = sw_if_index3;
252 clib_memcpy (t->src, h3->src_address, 6);
253 clib_memcpy (t->dst, h3->dst_address, 6);
257 vlib_node_increment_counter (vm, l2output_node.index,
258 L2OUTPUT_ERROR_L2OUTPUT, 4);
260 /* Get config for the output interface */
261 config0 = vec_elt_at_index (msm->configs, sw_if_index0);
262 config1 = vec_elt_at_index (msm->configs, sw_if_index1);
263 config2 = vec_elt_at_index (msm->configs, sw_if_index2);
264 config3 = vec_elt_at_index (msm->configs, sw_if_index3);
267 * Get features from the config
268 * TODO: mask out any non-applicable features
270 feature_bitmap0 = config0->feature_bitmap;
271 feature_bitmap1 = config1->feature_bitmap;
272 feature_bitmap2 = config2->feature_bitmap;
273 feature_bitmap3 = config3->feature_bitmap;
275 /* Determine next node */
276 l2_output_dispatch (msm->vlib_main,
283 b0, sw_if_index0, feature_bitmap0, &next0);
285 l2_output_dispatch (msm->vlib_main,
292 b1, sw_if_index1, feature_bitmap1, &next1);
294 l2_output_dispatch (msm->vlib_main,
301 b2, sw_if_index2, feature_bitmap2, &next2);
303 l2_output_dispatch (msm->vlib_main,
310 b3, sw_if_index3, feature_bitmap3, &next3);
312 l2output_vtr (node, config0, feature_bitmap0, b0, &next0);
313 l2output_vtr (node, config1, feature_bitmap1, b1, &next1);
314 l2output_vtr (node, config2, feature_bitmap2, b2, &next2);
315 l2output_vtr (node, config3, feature_bitmap3, b3, &next3);
318 * Perform the split horizon check
319 * The check can only fail for non-zero shg's
321 if (PREDICT_FALSE (config0->shg + config1->shg +
322 config2->shg + config3->shg))
324 /* one of the checks might fail, check both */
325 if (split_horizon_violation
326 (config0->shg, vnet_buffer (b0)->l2.shg))
328 next0 = L2OUTPUT_NEXT_DROP;
329 b0->error = node->errors[L2OUTPUT_ERROR_SHG_DROP];
331 if (split_horizon_violation
332 (config1->shg, vnet_buffer (b1)->l2.shg))
334 next1 = L2OUTPUT_NEXT_DROP;
335 b1->error = node->errors[L2OUTPUT_ERROR_SHG_DROP];
337 if (split_horizon_violation
338 (config2->shg, vnet_buffer (b2)->l2.shg))
340 next2 = L2OUTPUT_NEXT_DROP;
341 b2->error = node->errors[L2OUTPUT_ERROR_SHG_DROP];
343 if (split_horizon_violation
344 (config3->shg, vnet_buffer (b3)->l2.shg))
346 next3 = L2OUTPUT_NEXT_DROP;
347 b3->error = node->errors[L2OUTPUT_ERROR_SHG_DROP];
351 /* verify speculative enqueues, maybe switch current next frame */
352 /* if next0==next1==next_index then nothing special needs to be done */
353 vlib_validate_buffer_enqueue_x4 (vm, node, next_index,
354 to_next, n_left_to_next,
356 next0, next1, next2, next3);
359 while (n_left_from > 0 && n_left_to_next > 0)
365 ethernet_header_t *h0;
366 l2_output_config_t *config0;
369 /* speculatively enqueue b0 to the current next frame */
377 b0 = vlib_get_buffer (vm, bi0);
379 sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
381 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
382 && (b0->flags & VLIB_BUFFER_IS_TRACED)))
384 l2output_trace_t *t =
385 vlib_add_trace (vm, node, b0, sizeof (*t));
386 t->sw_if_index = sw_if_index0;
387 h0 = vlib_buffer_get_current (b0);
388 clib_memcpy (t->src, h0->src_address, 6);
389 clib_memcpy (t->dst, h0->dst_address, 6);
392 vlib_node_increment_counter (vm, l2output_node.index,
393 L2OUTPUT_ERROR_L2OUTPUT, 1);
395 /* Get config for the output interface */
396 config0 = vec_elt_at_index (msm->configs, sw_if_index0);
399 * Get features from the config
400 * TODO: mask out any non-applicable features
402 feature_bitmap0 = config0->feature_bitmap;
404 /* Determine next node */
405 l2_output_dispatch (msm->vlib_main,
412 b0, sw_if_index0, feature_bitmap0, &next0);
414 l2output_vtr (node, config0, feature_bitmap0, b0, &next0);
416 /* Perform the split horizon check */
418 (split_horizon_violation
419 (config0->shg, vnet_buffer (b0)->l2.shg)))
421 next0 = L2OUTPUT_NEXT_DROP;
422 b0->error = node->errors[L2OUTPUT_ERROR_SHG_DROP];
425 /* verify speculative enqueue, maybe switch current next frame */
426 vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
427 to_next, n_left_to_next,
431 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
434 return frame->n_vectors;
439 VLIB_REGISTER_NODE (l2output_node,static) = {
440 .function = l2output_node_fn,
442 .vector_size = sizeof (u32),
443 .format_trace = format_l2output_trace,
444 .type = VLIB_NODE_TYPE_INTERNAL,
446 .n_errors = ARRAY_LEN(l2output_error_strings),
447 .error_strings = l2output_error_strings,
449 .n_next_nodes = L2OUTPUT_N_NEXT,
451 /* edit / add dispositions here */
453 [L2OUTPUT_NEXT_DROP] = "error-drop",
454 [L2OUTPUT_NEXT_BAD_INTF] = "l2-output-bad-intf",
460 #define foreach_l2output_bad_intf_error \
461 _(DROP, "L2 output to interface not in L2 mode or deleted")
463 static char *l2output_bad_intf_error_strings[] = {
464 #define _(sym,string) string,
465 foreach_l2output_bad_intf_error
471 #define _(sym,str) L2OUTPUT_BAD_INTF_ERROR_##sym,
472 foreach_l2output_bad_intf_error
474 L2OUTPUT_BAD_INTF_N_ERROR,
475 } l2output_bad_intf_error_t;
479 * Output node for interfaces/tunnels which was in L2 mode but were changed
480 * to L3 mode or possibly deleted thereafter. On changing forwarding mode
481 * of any tunnel/interface from L2 to L3, its entry in l2_output_main table
482 * next_nodes.output_node_index_vec[sw_if_index] MUST be set to the value of
483 * L2OUTPUT_NEXT_BAD_INTF. Thus, if there are stale entries in the L2FIB for
484 * this sw_if_index, l2-output will send packets for this sw_if_index to the
485 * l2-output-bad-intf node which just setup the proper drop reason before
486 * sending packets to the error-drop node to drop the packet. Then, stale L2FIB
487 * entries for delted tunnels won't cause possible packet or memory corrpution.
489 static vlib_node_registration_t l2output_bad_intf_node;
492 l2output_bad_intf_node_fn (vlib_main_t * vm,
493 vlib_node_runtime_t * node, vlib_frame_t * frame)
495 u32 n_left_from, *from, *to_next;
496 l2output_next_t next_index = 0;
498 from = vlib_frame_vector_args (frame);
499 n_left_from = frame->n_vectors; /* number of packets to process */
501 while (n_left_from > 0)
505 /* get space to enqueue frame to graph node "next_index" */
506 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
508 while (n_left_from >= 4 && n_left_to_next >= 2)
511 vlib_buffer_t *b0, *b1;
513 to_next[0] = bi0 = from[0];
514 to_next[1] = bi1 = from[1];
519 b0 = vlib_get_buffer (vm, bi0);
520 b1 = vlib_get_buffer (vm, bi1);
521 b0->error = node->errors[L2OUTPUT_BAD_INTF_ERROR_DROP];
522 b1->error = node->errors[L2OUTPUT_BAD_INTF_ERROR_DROP];
525 while (n_left_from > 0 && n_left_to_next > 0)
536 b0 = vlib_get_buffer (vm, bi0);
537 b0->error = node->errors[L2OUTPUT_BAD_INTF_ERROR_DROP];
540 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
543 return frame->n_vectors;
547 VLIB_REGISTER_NODE (l2output_bad_intf_node,static) = {
548 .function = l2output_bad_intf_node_fn,
549 .name = "l2-output-bad-intf",
550 .vector_size = sizeof (u32),
551 .type = VLIB_NODE_TYPE_INTERNAL,
553 .n_errors = ARRAY_LEN(l2output_bad_intf_error_strings),
554 .error_strings = l2output_bad_intf_error_strings,
558 /* edit / add dispositions here */
566 VLIB_NODE_FUNCTION_MULTIARCH (l2output_node, l2output_node_fn)
567 clib_error_t *l2output_init (vlib_main_t * vm)
569 l2output_main_t *mp = &l2output_main;
572 mp->vnet_main = vnet_get_main ();
574 /* Create the config vector */
575 vec_validate (mp->configs, 100);
576 /* Until we hook up the CLI config, just create 100 sw interface entries and zero them */
578 /* Initialize the feature next-node indexes */
579 feat_bitmap_init_next_nodes (vm,
582 l2output_get_feat_names (),
583 mp->next_nodes.feat_next_node_index);
585 /* Initialize the output node mapping table */
586 l2output_init_output_node_vec (&mp->next_nodes.output_node_index_vec);
591 VLIB_INIT_FUNCTION (l2output_init);
597 } output_node_mapping_rpc_args_t;
599 static void output_node_rpc_callback (output_node_mapping_rpc_args_t * a);
602 output_node_mapping_send_rpc (u32 node_index, u32 sw_if_index)
604 output_node_mapping_rpc_args_t args;
605 void vl_api_rpc_call_main_thread (void *fp, u8 * data, u32 data_length);
607 args.node_index = node_index;
608 args.sw_if_index = sw_if_index;
610 vl_api_rpc_call_main_thread (output_node_rpc_callback,
611 (u8 *) & args, sizeof (args));
615 /** Create a mapping in the next node mapping table for the given sw_if_index. */
617 l2output_create_output_node_mapping (vlib_main_t * vlib_main, vnet_main_t * vnet_main, u32 node_index, /* index of current node */
618 u32 * output_node_index_vec,
622 u32 next; /* index of next graph node */
623 vnet_hw_interface_t *hw0;
626 hw0 = vnet_get_sup_hw_interface (vnet_main, sw_if_index);
630 cpu_number = os_get_cpu_number ();
636 oldflags = __sync_fetch_and_or (&hw0->flags,
637 VNET_HW_INTERFACE_FLAG_L2OUTPUT_MAPPED);
639 if ((oldflags & VNET_HW_INTERFACE_FLAG_L2OUTPUT_MAPPED))
640 return L2OUTPUT_NEXT_DROP;
642 output_node_mapping_send_rpc (node_index, sw_if_index);
643 return L2OUTPUT_NEXT_DROP;
646 /* dynamically create graph node arc */
647 next = vlib_node_add_next (vlib_main, node_index, hw0->output_node_index);
649 /* Initialize vector with the mapping */
651 node = vec_elt_at_index (output_node_index_vec, sw_if_index);
654 /* reset mapping bit, includes memory barrier */
655 __sync_fetch_and_and (&hw0->flags, ~VNET_HW_INTERFACE_FLAG_L2OUTPUT_MAPPED);
661 output_node_rpc_callback (output_node_mapping_rpc_args_t * a)
663 vlib_main_t *vm = vlib_get_main ();
664 vnet_main_t *vnm = vnet_get_main ();
665 l2output_main_t *mp = &l2output_main;
667 (void) l2output_create_output_node_mapping
668 (vm, vnm, a->node_index, mp->next_nodes.output_node_index_vec,
672 /* Get a pointer to the config for the given interface */
674 l2output_intf_config (u32 sw_if_index)
676 l2output_main_t *mp = &l2output_main;
678 vec_validate (mp->configs, sw_if_index);
679 return vec_elt_at_index (mp->configs, sw_if_index);
682 /** Enable (or disable) the feature in the bitmap for the given interface. */
684 l2output_intf_bitmap_enable (u32 sw_if_index, u32 feature_bitmap, u32 enable)
686 l2output_main_t *mp = &l2output_main;
687 l2_output_config_t *config;
689 vec_validate (mp->configs, sw_if_index);
690 config = vec_elt_at_index (mp->configs, sw_if_index);
694 config->feature_bitmap |= feature_bitmap;
698 config->feature_bitmap &= ~feature_bitmap;
703 * fd.io coding-style-patch-verification: ON
706 * eval: (c-set-style "gnu")