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Vector Packet Processing
mpls_output.c
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1 /*
2  * mpls_output.c: MPLS Adj rewrite
3  *
4  * Copyright (c) 2012-2014 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/pg/pg.h>
20 #include <vnet/ip/ip.h>
21 #include <vnet/mpls/mpls.h>
22 
23 typedef struct {
24  /* Adjacency taken. */
27 
28  /* Packet data, possibly *after* rewrite. */
29  u8 packet_data[64 - 1*sizeof(u32)];
31 
32 #define foreach_mpls_output_next \
33 _(DROP, "error-drop")
34 
35 typedef enum {
36 #define _(s,n) MPLS_OUTPUT_NEXT_##s,
38 #undef _
41 
42 static u8 *
43 format_mpls_output_trace (u8 * s, va_list * args)
44 {
45  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
46  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
47  mpls_output_trace_t * t = va_arg (*args, mpls_output_trace_t *);
48  uword indent = format_get_indent (s);
49 
50  s = format (s, "adj-idx %d : %U flow hash: 0x%08x",
51  t->adj_index,
53  t->flow_hash);
54  s = format (s, "\n%U%U",
55  format_white_space, indent,
57  t->adj_index, t->packet_data, sizeof (t->packet_data));
58  return s;
59 }
60 
61 static inline uword
63  vlib_node_runtime_t * node,
64  vlib_frame_t * from_frame,
65  int is_midchain)
66 {
67  u32 n_left_from, next_index, * from, * to_next, thread_index;
68  vlib_node_runtime_t * error_node;
69  u32 n_left_to_next;
70  mpls_main_t *mm;
71 
72  thread_index = vlib_get_thread_index();
73  error_node = vlib_node_get_runtime (vm, mpls_output_node.index);
74  from = vlib_frame_vector_args (from_frame);
75  n_left_from = from_frame->n_vectors;
76  next_index = node->cached_next_index;
77  mm = &mpls_main;
78 
79  while (n_left_from > 0)
80  {
81  vlib_get_next_frame (vm, node, next_index,
82  to_next, n_left_to_next);
83 
84  while (n_left_from >= 4 && n_left_to_next >= 2)
85  {
86  ip_adjacency_t * adj0;
88  vlib_buffer_t * p0;
89  u32 pi0, rw_len0, adj_index0, next0, error0;
90 
91  ip_adjacency_t * adj1;
93  vlib_buffer_t * p1;
94  u32 pi1, rw_len1, adj_index1, next1, error1;
95 
96  /* Prefetch next iteration. */
97  {
98  vlib_buffer_t * p2, * p3;
99 
100  p2 = vlib_get_buffer (vm, from[2]);
101  p3 = vlib_get_buffer (vm, from[3]);
102 
103  vlib_prefetch_buffer_header (p2, STORE);
104  vlib_prefetch_buffer_header (p3, STORE);
105 
106  CLIB_PREFETCH (p2->data, sizeof (hdr0[0]), STORE);
107  CLIB_PREFETCH (p3->data, sizeof (hdr1[0]), STORE);
108  }
109 
110  pi0 = to_next[0] = from[0];
111  pi1 = to_next[1] = from[1];
112 
113  from += 2;
114  n_left_from -= 2;
115  to_next += 2;
116  n_left_to_next -= 2;
117 
118  p0 = vlib_get_buffer (vm, pi0);
119  p1 = vlib_get_buffer (vm, pi1);
120 
121  adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
122  adj_index1 = vnet_buffer (p1)->ip.adj_index[VLIB_TX];
123 
124  adj0 = adj_get(adj_index0);
125  adj1 = adj_get(adj_index1);
126  hdr0 = vlib_buffer_get_current (p0);
127  hdr1 = vlib_buffer_get_current (p1);
128 
129  /* Guess we are only writing on simple Ethernet header. */
130  vnet_rewrite_two_headers (adj0[0], adj1[0], hdr0, hdr1,
131  sizeof (ethernet_header_t));
132 
133  /* Update packet buffer attributes/set output interface. */
134  rw_len0 = adj0[0].rewrite_header.data_bytes;
135  rw_len1 = adj1[0].rewrite_header.data_bytes;
136 
137  /* Bump the adj counters for packet and bytes */
140  thread_index,
141  adj_index0,
142  1,
143  vlib_buffer_length_in_chain (vm, p0) + rw_len0);
146  thread_index,
147  adj_index1,
148  1,
149  vlib_buffer_length_in_chain (vm, p1) + rw_len1);
150 
151  /* Check MTU of outgoing interface. */
153  adj0[0].rewrite_header.max_l3_packet_bytes))
154  {
155  p0->current_data -= rw_len0;
156  p0->current_length += rw_len0;
157 
158  vnet_buffer (p0)->sw_if_index[VLIB_TX] =
159  adj0[0].rewrite_header.sw_if_index;
160  next0 = adj0[0].rewrite_header.next_index;
161  error0 = IP4_ERROR_NONE;
162 
163  if (PREDICT_FALSE(adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
165  adj0[0].rewrite_header.sw_if_index,
166  &next0, p0);
167  }
168  else
169  {
170  error0 = IP4_ERROR_MTU_EXCEEDED;
171  next0 = MPLS_OUTPUT_NEXT_DROP;
172  }
174  adj1[0].rewrite_header.max_l3_packet_bytes))
175  {
176  p1->current_data -= rw_len1;
177  p1->current_length += rw_len1;
178 
179  vnet_buffer (p1)->sw_if_index[VLIB_TX] =
180  adj1[0].rewrite_header.sw_if_index;
181  next1 = adj1[0].rewrite_header.next_index;
182  error1 = IP4_ERROR_NONE;
183 
184  if (PREDICT_FALSE(adj1[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
186  adj1[0].rewrite_header.sw_if_index,
187  &next1, p1);
188  }
189  else
190  {
191  error1 = IP4_ERROR_MTU_EXCEEDED;
192  next1 = MPLS_OUTPUT_NEXT_DROP;
193  }
194  if (is_midchain)
195  {
196  adj0->sub_type.midchain.fixup_func(vm, adj0, p0);
197  adj1->sub_type.midchain.fixup_func(vm, adj1, p1);
198  }
199 
200  p0->error = error_node->errors[error0];
201  p1->error = error_node->errors[error1];
202 
204  {
205  mpls_output_trace_t *tr = vlib_add_trace (vm, node,
206  p0, sizeof (*tr));
207  tr->adj_index = vnet_buffer(p0)->ip.adj_index[VLIB_TX];
208  tr->flow_hash = vnet_buffer(p0)->ip.flow_hash;
211  sizeof (tr->packet_data));
212  }
214  {
215  mpls_output_trace_t *tr = vlib_add_trace (vm, node,
216  p1, sizeof (*tr));
217  tr->adj_index = vnet_buffer(p1)->ip.adj_index[VLIB_TX];
218  tr->flow_hash = vnet_buffer(p1)->ip.flow_hash;
221  sizeof (tr->packet_data));
222  }
223 
224  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
225  to_next, n_left_to_next,
226  pi0, pi1, next0, next1);
227  }
228 
229  while (n_left_from > 0 && n_left_to_next > 0)
230  {
231  ip_adjacency_t * adj0;
232  mpls_unicast_header_t *hdr0;
233  vlib_buffer_t * p0;
234  u32 pi0, rw_len0, adj_index0, next0, error0;
235 
236  pi0 = to_next[0] = from[0];
237 
238  p0 = vlib_get_buffer (vm, pi0);
239 
240  adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
241 
242  adj0 = adj_get(adj_index0);
243  hdr0 = vlib_buffer_get_current (p0);
244 
245  /* Guess we are only writing on simple Ethernet header. */
246  vnet_rewrite_one_header (adj0[0], hdr0,
247  sizeof (ethernet_header_t));
248 
249  /* Update packet buffer attributes/set output interface. */
250  rw_len0 = adj0[0].rewrite_header.data_bytes;
251 
254  thread_index,
255  adj_index0,
256  1,
257  vlib_buffer_length_in_chain (vm, p0) + rw_len0);
258 
259  /* Check MTU of outgoing interface. */
261  adj0[0].rewrite_header.max_l3_packet_bytes))
262  {
263  p0->current_data -= rw_len0;
264  p0->current_length += rw_len0;
265 
266  vnet_buffer (p0)->sw_if_index[VLIB_TX] =
267  adj0[0].rewrite_header.sw_if_index;
268  next0 = adj0[0].rewrite_header.next_index;
269  error0 = IP4_ERROR_NONE;
270 
271  if (PREDICT_FALSE(adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
273  adj0[0].rewrite_header.sw_if_index,
274  &next0, p0);
275  }
276  else
277  {
278  error0 = IP4_ERROR_MTU_EXCEEDED;
279  next0 = MPLS_OUTPUT_NEXT_DROP;
280  }
281  if (is_midchain)
282  {
283  adj0->sub_type.midchain.fixup_func(vm, adj0, p0);
284  }
285 
286  p0->error = error_node->errors[error0];
287 
288  from += 1;
289  n_left_from -= 1;
290  to_next += 1;
291  n_left_to_next -= 1;
292 
294  {
295  mpls_output_trace_t *tr = vlib_add_trace (vm, node,
296  p0, sizeof (*tr));
297  tr->adj_index = vnet_buffer(p0)->ip.adj_index[VLIB_TX];
298  tr->flow_hash = vnet_buffer(p0)->ip.flow_hash;
299  }
300 
301  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
302  to_next, n_left_to_next,
303  pi0, next0);
304  }
305 
306  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
307  }
309  MPLS_ERROR_PKTS_ENCAP,
310  from_frame->n_vectors);
311 
312  return from_frame->n_vectors;
313 }
314 
315 static char * mpls_error_strings[] = {
316 #define mpls_error(n,s) s,
317 #include "error.def"
318 #undef mpls_error
319 };
320 
321 static inline uword
323  vlib_node_runtime_t * node,
324  vlib_frame_t * from_frame)
325 {
326  return (mpls_output_inline(vm, node, from_frame, /* is_midchain */ 0));
327 }
328 
330  .function = mpls_output,
331  .name = "mpls-output",
332  /* Takes a vector of packets. */
333  .vector_size = sizeof (u32),
334  .n_errors = MPLS_N_ERROR,
335  .error_strings = mpls_error_strings,
336 
337  .n_next_nodes = MPLS_OUTPUT_N_NEXT,
338  .next_nodes = {
339 #define _(s,n) [MPLS_OUTPUT_NEXT_##s] = n,
341 #undef _
342  },
343 
344  .format_trace = format_mpls_output_trace,
345 };
346 
348 
349 static inline uword
351  vlib_node_runtime_t * node,
352  vlib_frame_t * from_frame)
353 {
354  return (mpls_output_inline(vm, node, from_frame, /* is_midchain */ 1));
355 }
356 
358  .function = mpls_midchain,
359  .name = "mpls-midchain",
360  .vector_size = sizeof (u32),
361 
362  .format_trace = format_mpls_output_trace,
363 
364  .sibling_of = "mpls-output",
365 };
366 
368 
369 /**
370  * @brief Next index values from the MPLS incomplete adj node
371  */
372 #define foreach_mpls_adj_incomplete_next \
373 _(DROP, "error-drop") \
374 _(IP4, "ip4-arp") \
375 _(IP6, "ip6-discover-neighbor")
376 
377 typedef enum {
378 #define _(s,n) MPLS_ADJ_INCOMPLETE_NEXT_##s,
380 #undef _
383 
384 /**
385  * @brief A struct to hold tracing information for the MPLS label imposition
386  * node.
387  */
389 {
392 
393 
394 /**
395  * @brief Graph node for incomplete MPLS adjacency.
396  * This node will push traffic to either the v4-arp or v6-nd node
397  * based on the next-hop proto of the adj.
398  * We pay a cost for this 'routing' node, but an incomplete adj is the
399  * exception case.
400  */
401 static inline uword
403  vlib_node_runtime_t * node,
404  vlib_frame_t * from_frame)
405 {
406  u32 n_left_from, next_index, * from, * to_next;
407 
408  from = vlib_frame_vector_args (from_frame);
409  n_left_from = from_frame->n_vectors;
410  next_index = node->cached_next_index;
411 
412  while (n_left_from > 0)
413  {
414  u32 n_left_to_next;
415 
416  vlib_get_next_frame (vm, node, next_index,
417  to_next, n_left_to_next);
418 
419  while (n_left_from > 0 && n_left_to_next > 0)
420  {
421  u32 pi0, next0, adj_index0;
422  ip_adjacency_t * adj0;
423  vlib_buffer_t * p0;
424 
425  pi0 = to_next[0] = from[0];
426  p0 = vlib_get_buffer (vm, pi0);
427  from += 1;
428  n_left_from -= 1;
429  to_next += 1;
430  n_left_to_next -= 1;
431 
432  adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
433 
434  adj0 = adj_get(adj_index0);
435 
437  {
438  next0 = MPLS_ADJ_INCOMPLETE_NEXT_IP4;
439  }
440  else
441  {
442  next0 = MPLS_ADJ_INCOMPLETE_NEXT_IP6;
443  }
444 
446  {
448  vlib_add_trace (vm, node, p0, sizeof (*tr));
449  tr->next = next0;
450  }
451 
452  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
453  to_next, n_left_to_next,
454  pi0, next0);
455  }
456 
457  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
458  }
459 
460  return from_frame->n_vectors;
461 }
462 
463 static u8 *
465 {
466  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
467  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
469  uword indent;
470 
471  t = va_arg (*args, mpls_adj_incomplete_trace_t *);
472  indent = format_get_indent (s);
473 
474  s = format (s, "%Unext:%d",
475  format_white_space, indent,
476  t->next);
477  return (s);
478 }
479 
481  .function = mpls_adj_incomplete,
482  .name = "mpls-adj-incomplete",
483  .format_trace = format_mpls_adj_incomplete_trace,
484  /* Takes a vector of packets. */
485  .vector_size = sizeof (u32),
486  .n_errors = MPLS_N_ERROR,
487  .error_strings = mpls_error_strings,
488 
489  .n_next_nodes = MPLS_ADJ_INCOMPLETE_N_NEXT,
490  .next_nodes = {
491 #define _(s,n) [MPLS_ADJ_INCOMPLETE_NEXT_##s] = n,
493 #undef _
494  },
495 };
496 
#define vnet_rewrite_one_header(rw0, p0, most_likely_size)
Definition: rewrite.h:281
#define foreach_mpls_output_next
Definition: mpls_output.c:32
#define CLIB_UNUSED(x)
Definition: clib.h:79
format_function_t format_ip_adjacency_packet_data
Definition: format.h:59
static void vlib_increment_combined_counter(vlib_combined_counter_main_t *cm, u32 thread_index, u32 index, u64 n_packets, u64 n_bytes)
Increment a combined counter.
Definition: counter.h:211
#define PREDICT_TRUE(x)
Definition: clib.h:98
IP unicast adjacency.
Definition: adj.h:174
A struct to hold tracing information for the MPLS label imposition node.
Definition: mpls_output.c:388
void vlib_put_next_frame(vlib_main_t *vm, vlib_node_runtime_t *r, u32 next_index, u32 n_vectors_left)
Release pointer to next frame vector data.
Definition: main.c:459
static u8 * format_mpls_adj_incomplete_trace(u8 *s, va_list *args)
Definition: mpls_output.c:464
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:419
union ip_adjacency_t_::@37 sub_type
vlib_error_t * errors
Vector of errors for this node.
Definition: node.h:419
static uword vlib_buffer_length_in_chain(vlib_main_t *vm, vlib_buffer_t *b)
Get length in bytes of the buffer chain.
Definition: buffer_funcs.h:100
static u8 * format_mpls_output_trace(u8 *s, va_list *args)
Definition: mpls_output.c:43
vlib_node_registration_t mpls_midchain_node
(constructor) VLIB_REGISTER_NODE (mpls_midchain_node)
Definition: mpls_output.c:357
vlib_node_registration_t mpls_output_node
(constructor) VLIB_REGISTER_NODE (mpls_output_node)
Definition: mpls_output.c:329
static ip_adjacency_t * adj_get(adj_index_t adj_index)
Get a pointer to an adjacency object from its index.
Definition: adj.h:365
i16 current_data
signed offset in data[], pre_data[] that we are currently processing.
Definition: buffer.h:67
format_function_t format_ip_adjacency
Definition: format.h:58
static uword format_get_indent(u8 *s)
Definition: format.h:72
u8 * format_white_space(u8 *s, va_list *va)
Definition: std-formats.c:113
#define vlib_prefetch_buffer_header(b, type)
Prefetch buffer metadata.
Definition: buffer.h:164
mpls_adj_incomplete_next_t
Definition: mpls_output.c:377
mpls_output_next_t
Definition: mpls_output.c:35
u8 output_feature_arc_index
Definition: mpls.h:55
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:71
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:188
static uword mpls_adj_incomplete(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
Graph node for incomplete MPLS adjacency.
Definition: mpls_output.c:402
#define PREDICT_FALSE(x)
Definition: clib.h:97
struct ip_adjacency_t_::@37::@39 midchain
IP_LOOKUP_NEXT_MIDCHAIN.
#define vlib_validate_buffer_enqueue_x2(vm, node, next_index, to_next, n_left_to_next, bi0, bi1, next0, next1)
Finish enqueueing two buffers forward in the graph.
Definition: buffer_node.h:70
#define vlib_validate_buffer_enqueue_x1(vm, node, next_index, to_next, n_left_to_next, bi0, next0)
Finish enqueueing one buffer forward in the graph.
Definition: buffer_node.h:216
#define vlib_get_next_frame(vm, node, next_index, vectors, n_vectors_left)
Get pointer to next frame vector data by (vlib_node_runtime_t, next_index).
Definition: node_funcs.h:366
vlib_combined_counter_main_t adjacency_counters
Adjacency packet counters.
Definition: adj.c:25
vlib_error_t error
Error code for buffers to be enqueued to error handler.
Definition: buffer.h:113
static void vlib_node_increment_counter(vlib_main_t *vm, u32 node_index, u32 counter_index, u64 increment)
Definition: node_funcs.h:1131
static uword mpls_output(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
Definition: mpls_output.c:322
u16 n_vectors
Definition: node.h:345
mpls_main_t mpls_main
Definition: mpls.c:25
static_always_inline uword vlib_get_thread_index(void)
Definition: threads.h:185
#define CLIB_PREFETCH(addr, size, type)
Definition: cache.h:82
#define foreach_mpls_adj_incomplete_next
Next index values from the MPLS incomplete adj node.
Definition: mpls_output.c:372
#define VLIB_BUFFER_IS_TRACED
Definition: buffer.h:85
static vlib_node_runtime_t * vlib_node_get_runtime(vlib_main_t *vm, u32 node_index)
Get node runtime by node index.
Definition: node_funcs.h:88
#define clib_memcpy(a, b, c)
Definition: string.h:69
u16 cached_next_index
Next frame index that vector arguments were last enqueued to last time this node ran.
Definition: node.h:460
static uword mpls_output_inline(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame, int is_midchain)
Definition: mpls_output.c:62
unsigned int u32
Definition: types.h:88
u64 uword
Definition: types.h:112
static void * vlib_add_trace(vlib_main_t *vm, vlib_node_runtime_t *r, vlib_buffer_t *b, u32 n_data_bytes)
Definition: trace_funcs.h:55
static char * mpls_error_strings[]
Definition: mpls_output.c:315
fib_protocol_t ia_nh_proto
The protocol of the neighbor/peer.
Definition: adj.h:202
Definition: defs.h:47
unsigned char u8
Definition: types.h:56
static void * vlib_frame_vector_args(vlib_frame_t *f)
Get pointer to frame vector data.
Definition: node_funcs.h:269
#define vnet_buffer(b)
Definition: buffer.h:304
#define VLIB_NODE_FUNCTION_MULTIARCH(node, fn)
Definition: node.h:159
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:144
u8 data[0]
Packet data.
Definition: buffer.h:152
struct mpls_adj_incomplete_trace_t_ mpls_adj_incomplete_trace_t
A struct to hold tracing information for the MPLS label imposition node.
u8 packet_data[64-1 *sizeof(u32)]
Definition: mpls_output.c:29
vlib_node_registration_t mpls_adj_incomplete_node
(constructor) VLIB_REGISTER_NODE (mpls_adj_incomplete_node)
Definition: mpls_output.c:480
#define vnet_rewrite_two_headers(rw0, rw1, p0, p1, most_likely_size)
Definition: rewrite.h:286
u32 flags
buffer flags: VLIB_BUFFER_IS_TRACED: trace this buffer.
Definition: buffer.h:74
This adjacency/interface has output features configured.
Definition: rewrite.h:57
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:57
static uword mpls_midchain(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
Definition: mpls_output.c:350
static_always_inline void vnet_feature_arc_start(u8 arc, u32 sw_if_index, u32 *next0, vlib_buffer_t *b0)
Definition: feature.h:201