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Vector Packet Processing
ip6_forward.h
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1 /*
2  * Copyright (c) 2016 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 /*
16  * ip/ip6_forward.h: IP v6 forwarding
17  *
18  * Copyright (c) 2008 Eliot Dresselhaus
19  *
20  * Permission is hereby granted, free of charge, to any person obtaining
21  * a copy of this software and associated documentation files (the
22  * "Software"), to deal in the Software without restriction, including
23  * without limitation the rights to use, copy, modify, merge, publish,
24  * distribute, sublicense, and/or sell copies of the Software, and to
25  * permit persons to whom the Software is furnished to do so, subject to
26  * the following conditions:
27  *
28  * The above copyright notice and this permission notice shall be
29  * included in all copies or substantial portions of the Software.
30  *
31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38  */
39 
40 #ifndef __included_ip6_forward_h__
41 #define __included_ip6_forward_h__
42 
43 #include <vnet/fib/ip6_fib.h>
45 
46 /**
47  * @file
48  * @brief IPv6 Forwarding.
49  *
50  * This file contains the source code for IPv6 forwarding.
51  */
52 
53 
56  vlib_node_runtime_t * node, vlib_frame_t * frame)
57 {
58  ip6_main_t *im = &ip6_main;
60  u32 n_left_from, n_left_to_next, *from, *to_next;
61  ip_lookup_next_t next;
62  u32 thread_index = vlib_get_thread_index ();
63 
64  from = vlib_frame_vector_args (frame);
65  n_left_from = frame->n_vectors;
66  next = node->cached_next_index;
67 
68  while (n_left_from > 0)
69  {
70  vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
71 
72  while (n_left_from >= 4 && n_left_to_next >= 2)
73  {
74  vlib_buffer_t *p0, *p1;
75  u32 pi0, pi1, lbi0, lbi1, wrong_next;
76  ip_lookup_next_t next0, next1;
77  ip6_header_t *ip0, *ip1;
78  ip6_address_t *dst_addr0, *dst_addr1;
79  u32 fib_index0, fib_index1;
80  u32 flow_hash_config0, flow_hash_config1;
81  const dpo_id_t *dpo0, *dpo1;
82  const load_balance_t *lb0, *lb1;
83 
84  /* Prefetch next iteration. */
85  {
86  vlib_buffer_t *p2, *p3;
87 
88  p2 = vlib_get_buffer (vm, from[2]);
89  p3 = vlib_get_buffer (vm, from[3]);
90 
91  vlib_prefetch_buffer_header (p2, LOAD);
92  vlib_prefetch_buffer_header (p3, LOAD);
93  CLIB_PREFETCH (p2->data, sizeof (ip0[0]), LOAD);
94  CLIB_PREFETCH (p3->data, sizeof (ip0[0]), LOAD);
95  }
96 
97  pi0 = to_next[0] = from[0];
98  pi1 = to_next[1] = from[1];
99 
100  p0 = vlib_get_buffer (vm, pi0);
101  p1 = vlib_get_buffer (vm, pi1);
102 
103  ip0 = vlib_buffer_get_current (p0);
104  ip1 = vlib_buffer_get_current (p1);
105 
106  dst_addr0 = &ip0->dst_address;
107  dst_addr1 = &ip1->dst_address;
108 
109  fib_index0 =
111  vnet_buffer (p0)->sw_if_index[VLIB_RX]);
112  fib_index1 =
114  vnet_buffer (p1)->sw_if_index[VLIB_RX]);
115 
116  fib_index0 = (vnet_buffer (p0)->sw_if_index[VLIB_TX] == (u32) ~ 0) ?
117  fib_index0 : vnet_buffer (p0)->sw_if_index[VLIB_TX];
118  fib_index1 = (vnet_buffer (p1)->sw_if_index[VLIB_TX] == (u32) ~ 0) ?
119  fib_index1 : vnet_buffer (p1)->sw_if_index[VLIB_TX];
120 
121  lbi0 = ip6_fib_table_fwding_lookup (im, fib_index0, dst_addr0);
122  lbi1 = ip6_fib_table_fwding_lookup (im, fib_index1, dst_addr1);
123 
124  lb0 = load_balance_get (lbi0);
125  lb1 = load_balance_get (lbi1);
126  ASSERT (lb0->lb_n_buckets > 0);
127  ASSERT (lb1->lb_n_buckets > 0);
128  ASSERT (is_pow2 (lb0->lb_n_buckets));
129  ASSERT (is_pow2 (lb1->lb_n_buckets));
130 
131  vnet_buffer (p0)->ip.flow_hash = vnet_buffer (p1)->ip.flow_hash = 0;
132 
133  if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
134  {
135  flow_hash_config0 = lb0->lb_hash_config;
136  vnet_buffer (p0)->ip.flow_hash =
137  ip6_compute_flow_hash (ip0, flow_hash_config0);
138  dpo0 =
140  (vnet_buffer (p0)->ip.flow_hash &
141  (lb0->lb_n_buckets_minus_1)));
142  }
143  else
144  {
145  dpo0 = load_balance_get_bucket_i (lb0, 0);
146  }
147  if (PREDICT_FALSE (lb1->lb_n_buckets > 1))
148  {
149  flow_hash_config1 = lb1->lb_hash_config;
150  vnet_buffer (p1)->ip.flow_hash =
151  ip6_compute_flow_hash (ip1, flow_hash_config1);
152  dpo1 =
154  (vnet_buffer (p1)->ip.flow_hash &
155  (lb1->lb_n_buckets_minus_1)));
156  }
157  else
158  {
159  dpo1 = load_balance_get_bucket_i (lb1, 0);
160  }
161  next0 = dpo0->dpoi_next_node;
162  next1 = dpo1->dpoi_next_node;
163 
164  /* Only process the HBH Option Header if explicitly configured to do so */
165  if (PREDICT_FALSE
166  (ip0->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS))
167  {
168  next0 = (dpo_is_adj (dpo0) && im->hbh_enabled) ?
170  }
171  if (PREDICT_FALSE
172  (ip1->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS))
173  {
174  next1 = (dpo_is_adj (dpo1) && im->hbh_enabled) ?
176  }
177  vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
178  vnet_buffer (p1)->ip.adj_index[VLIB_TX] = dpo1->dpoi_index;
179 
181  (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
183  (cm, thread_index, lbi1, 1, vlib_buffer_length_in_chain (vm, p1));
184 
185  from += 2;
186  to_next += 2;
187  n_left_to_next -= 2;
188  n_left_from -= 2;
189 
190  wrong_next = (next0 != next) + 2 * (next1 != next);
191  if (PREDICT_FALSE (wrong_next != 0))
192  {
193  switch (wrong_next)
194  {
195  case 1:
196  /* A B A */
197  to_next[-2] = pi1;
198  to_next -= 1;
199  n_left_to_next += 1;
200  vlib_set_next_frame_buffer (vm, node, next0, pi0);
201  break;
202 
203  case 2:
204  /* A A B */
205  to_next -= 1;
206  n_left_to_next += 1;
207  vlib_set_next_frame_buffer (vm, node, next1, pi1);
208  break;
209 
210  case 3:
211  /* A B C */
212  to_next -= 2;
213  n_left_to_next += 2;
214  vlib_set_next_frame_buffer (vm, node, next0, pi0);
215  vlib_set_next_frame_buffer (vm, node, next1, pi1);
216  if (next0 == next1)
217  {
218  /* A B B */
219  vlib_put_next_frame (vm, node, next, n_left_to_next);
220  next = next1;
221  vlib_get_next_frame (vm, node, next, to_next,
222  n_left_to_next);
223  }
224  }
225  }
226  }
227 
228  while (n_left_from > 0 && n_left_to_next > 0)
229  {
230  vlib_buffer_t *p0;
231  ip6_header_t *ip0;
232  u32 pi0, lbi0;
233  ip_lookup_next_t next0;
234  load_balance_t *lb0;
235  ip6_address_t *dst_addr0;
236  u32 fib_index0, flow_hash_config0;
237  const dpo_id_t *dpo0;
238 
239  pi0 = from[0];
240  to_next[0] = pi0;
241 
242  p0 = vlib_get_buffer (vm, pi0);
243 
244  ip0 = vlib_buffer_get_current (p0);
245 
246  dst_addr0 = &ip0->dst_address;
247 
248  fib_index0 =
250  vnet_buffer (p0)->sw_if_index[VLIB_RX]);
251  fib_index0 =
252  (vnet_buffer (p0)->sw_if_index[VLIB_TX] ==
253  (u32) ~ 0) ? fib_index0 : vnet_buffer (p0)->sw_if_index[VLIB_TX];
254 
255  lbi0 = ip6_fib_table_fwding_lookup (im, fib_index0, dst_addr0);
256 
257  lb0 = load_balance_get (lbi0);
258  flow_hash_config0 = lb0->lb_hash_config;
259 
260  vnet_buffer (p0)->ip.flow_hash = 0;
261  ASSERT (lb0->lb_n_buckets > 0);
262  ASSERT (is_pow2 (lb0->lb_n_buckets));
263 
264  if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
265  {
266  flow_hash_config0 = lb0->lb_hash_config;
267  vnet_buffer (p0)->ip.flow_hash =
268  ip6_compute_flow_hash (ip0, flow_hash_config0);
269  dpo0 =
271  (vnet_buffer (p0)->ip.flow_hash &
272  (lb0->lb_n_buckets_minus_1)));
273  }
274  else
275  {
276  dpo0 = load_balance_get_bucket_i (lb0, 0);
277  }
278 
279  dpo0 = load_balance_get_bucket_i (lb0,
280  (vnet_buffer (p0)->ip.flow_hash &
281  lb0->lb_n_buckets_minus_1));
282  next0 = dpo0->dpoi_next_node;
283 
284  /* Only process the HBH Option Header if explicitly configured to do so */
285  if (PREDICT_FALSE
286  (ip0->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS))
287  {
288  next0 = (dpo_is_adj (dpo0) && im->hbh_enabled) ?
290  }
291  vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
292 
294  (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
295 
296  from += 1;
297  to_next += 1;
298  n_left_to_next -= 1;
299  n_left_from -= 1;
300 
301  if (PREDICT_FALSE (next0 != next))
302  {
303  n_left_to_next += 1;
304  vlib_put_next_frame (vm, node, next, n_left_to_next);
305  next = next0;
306  vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
307  to_next[0] = pi0;
308  to_next += 1;
309  n_left_to_next -= 1;
310  }
311  }
312 
313  vlib_put_next_frame (vm, node, next, n_left_to_next);
314  }
315 
316  if (node->flags & VLIB_NODE_FLAG_TRACE)
317  ip6_forward_next_trace (vm, node, frame, VLIB_TX);
318 
319  return frame->n_vectors;
320 }
321 
322 #endif /*__included_ip6_forward_h__ */
323 
324 /*
325  * fd.io coding-style-patch-verification: ON
326  *
327  * Local Variables:
328  * eval: (c-set-style "gnu")
329  * End:
330  */
u16 lb_n_buckets
number of buckets in the load-balance.
Definition: load_balance.h:94
vlib_combined_counter_main_t lbm_to_counters
Definition: load_balance.h:46
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
int dpo_is_adj(const dpo_id_t *dpo)
Return TRUE is the DPO is any type of adjacency.
Definition: dpo.c:277
static void vlib_set_next_frame_buffer(vlib_main_t *vm, vlib_node_runtime_t *node, u32 next_index, u32 buffer_index)
Definition: node_funcs.h:397
flow_hash_config_t lb_hash_config
the hash config to use when selecting a bucket.
Definition: load_balance.h:134
static const dpo_id_t * load_balance_get_fwd_bucket(const load_balance_t *lb, u16 bucket)
static uword ip6_lookup_inline(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
Definition: ip6_forward.h:55
static u32 ip6_fib_table_fwding_lookup(ip6_main_t *im, u32 fib_index, const ip6_address_t *dst)
Definition: ip6_fib.h:67
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:107
ip_lookup_next_t
An adjacency is a representation of an attached L3 peer.
Definition: adj.h:50
#define always_inline
Definition: clib.h:92
u16 lb_n_buckets_minus_1
number of buckets in the load-balance - 1.
Definition: load_balance.h:99
#define vlib_prefetch_buffer_header(b, type)
Prefetch buffer metadata.
Definition: buffer.h:191
The identity of a DPO is a combination of its type and its instance number/index of objects of that t...
Definition: dpo.h:168
static const dpo_id_t * load_balance_get_bucket_i(const load_balance_t *lb, u32 bucket)
Definition: load_balance.h:209
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:209
static u32 ip6_compute_flow_hash(const ip6_header_t *ip, flow_hash_config_t flow_hash_config)
Definition: ip6.h:428
The FIB DPO provieds;.
Definition: load_balance.h:84
#define PREDICT_FALSE(x)
Definition: clib.h:105
load_balance_main_t load_balance_main
The one instance of load-balance main.
Definition: load_balance.c:56
#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:364
u16 n_vectors
Definition: node.h:344
static_always_inline uword vlib_get_thread_index(void)
Definition: threads.h:221
#define CLIB_PREFETCH(addr, size, type)
Definition: cache.h:74
vlib_main_t * vm
Definition: buffer.c:294
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:454
u8 hbh_enabled
Definition: ip6.h:221
u16 cached_next_index
Next frame index that vector arguments were last enqueued to last time this node ran.
Definition: node.h:456
#define ASSERT(truth)
unsigned int u32
Definition: types.h:88
ip6_main_t ip6_main
Definition: ip6_forward.c:2750
static load_balance_t * load_balance_get(index_t lbi)
Definition: load_balance.h:200
static uword is_pow2(uword x)
Definition: clib.h:280
u64 uword
Definition: types.h:112
#define vec_elt(v, i)
Get vector value at index i.
Definition: defs.h:47
index_t dpoi_index
the index of objects of that type
Definition: dpo.h:184
static void * vlib_frame_vector_args(vlib_frame_t *f)
Get pointer to frame vector data.
Definition: node_funcs.h:267
A collection of combined counters.
Definition: counter.h:180
#define vnet_buffer(b)
Definition: buffer.h:372
u8 data[0]
Packet data.
Definition: buffer.h:179
void ip6_forward_next_trace(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame, vlib_rx_or_tx_t which_adj_index)
Definition: ip6_forward.c:773
u16 flags
Copy of main node flags.
Definition: node.h:450
u16 dpoi_next_node
The next VLIB node to follow.
Definition: dpo.h:180
#define VLIB_NODE_FLAG_TRACE
Definition: node.h:259
u32 * fib_index_by_sw_if_index
Definition: ip6.h:176
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
Definition: defs.h:46
ip6_address_t dst_address
Definition: ip6_packet.h:342