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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 = vm->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 flow_hash_config0, flow_hash_config1;
80  const dpo_id_t *dpo0, *dpo1;
81  const load_balance_t *lb0, *lb1;
82 
83  /* Prefetch next iteration. */
84  {
85  vlib_buffer_t *p2, *p3;
86 
87  p2 = vlib_get_buffer (vm, from[2]);
88  p3 = vlib_get_buffer (vm, from[3]);
89 
90  vlib_prefetch_buffer_header (p2, LOAD);
91  vlib_prefetch_buffer_header (p3, LOAD);
92  CLIB_PREFETCH (p2->data, sizeof (ip0[0]), LOAD);
93  CLIB_PREFETCH (p3->data, sizeof (ip0[0]), LOAD);
94  }
95 
96  pi0 = to_next[0] = from[0];
97  pi1 = to_next[1] = from[1];
98 
99  p0 = vlib_get_buffer (vm, pi0);
100  p1 = vlib_get_buffer (vm, pi1);
101 
102  ip0 = vlib_buffer_get_current (p0);
103  ip1 = vlib_buffer_get_current (p1);
104 
105  dst_addr0 = &ip0->dst_address;
106  dst_addr1 = &ip1->dst_address;
107 
110 
111  lbi0 = ip6_fib_table_fwding_lookup (im,
112  vnet_buffer (p0)->ip.fib_index,
113  dst_addr0);
114  lbi1 = ip6_fib_table_fwding_lookup (im,
115  vnet_buffer (p1)->ip.fib_index,
116  dst_addr1);
117 
118  lb0 = load_balance_get (lbi0);
119  lb1 = load_balance_get (lbi1);
120  ASSERT (lb0->lb_n_buckets > 0);
121  ASSERT (lb1->lb_n_buckets > 0);
122  ASSERT (is_pow2 (lb0->lb_n_buckets));
123  ASSERT (is_pow2 (lb1->lb_n_buckets));
124 
125  vnet_buffer (p0)->ip.flow_hash = vnet_buffer (p1)->ip.flow_hash = 0;
126 
127  if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
128  {
129  flow_hash_config0 = lb0->lb_hash_config;
130  vnet_buffer (p0)->ip.flow_hash =
131  ip6_compute_flow_hash (ip0, flow_hash_config0);
132  dpo0 =
134  (vnet_buffer (p0)->ip.flow_hash &
135  (lb0->lb_n_buckets_minus_1)));
136  }
137  else
138  {
139  dpo0 = load_balance_get_bucket_i (lb0, 0);
140  }
141  if (PREDICT_FALSE (lb1->lb_n_buckets > 1))
142  {
143  flow_hash_config1 = lb1->lb_hash_config;
144  vnet_buffer (p1)->ip.flow_hash =
145  ip6_compute_flow_hash (ip1, flow_hash_config1);
146  dpo1 =
148  (vnet_buffer (p1)->ip.flow_hash &
149  (lb1->lb_n_buckets_minus_1)));
150  }
151  else
152  {
153  dpo1 = load_balance_get_bucket_i (lb1, 0);
154  }
155  next0 = dpo0->dpoi_next_node;
156  next1 = dpo1->dpoi_next_node;
157 
158  /* Only process the HBH Option Header if explicitly configured to do so */
159  if (PREDICT_FALSE
160  (ip0->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS))
161  {
162  next0 = (dpo_is_adj (dpo0) && im->hbh_enabled) ?
164  }
165  if (PREDICT_FALSE
166  (ip1->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS))
167  {
168  next1 = (dpo_is_adj (dpo1) && im->hbh_enabled) ?
170  }
171  vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
172  vnet_buffer (p1)->ip.adj_index[VLIB_TX] = dpo1->dpoi_index;
173 
175  (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
177  (cm, thread_index, lbi1, 1, vlib_buffer_length_in_chain (vm, p1));
178 
179  from += 2;
180  to_next += 2;
181  n_left_to_next -= 2;
182  n_left_from -= 2;
183 
184  wrong_next = (next0 != next) + 2 * (next1 != next);
185  if (PREDICT_FALSE (wrong_next != 0))
186  {
187  switch (wrong_next)
188  {
189  case 1:
190  /* A B A */
191  to_next[-2] = pi1;
192  to_next -= 1;
193  n_left_to_next += 1;
194  vlib_set_next_frame_buffer (vm, node, next0, pi0);
195  break;
196 
197  case 2:
198  /* A A B */
199  to_next -= 1;
200  n_left_to_next += 1;
201  vlib_set_next_frame_buffer (vm, node, next1, pi1);
202  break;
203 
204  case 3:
205  /* A B C */
206  to_next -= 2;
207  n_left_to_next += 2;
208  vlib_set_next_frame_buffer (vm, node, next0, pi0);
209  vlib_set_next_frame_buffer (vm, node, next1, pi1);
210  if (next0 == next1)
211  {
212  /* A B B */
213  vlib_put_next_frame (vm, node, next, n_left_to_next);
214  next = next1;
215  vlib_get_next_frame (vm, node, next, to_next,
216  n_left_to_next);
217  }
218  }
219  }
220  }
221 
222  while (n_left_from > 0 && n_left_to_next > 0)
223  {
224  vlib_buffer_t *p0;
225  ip6_header_t *ip0;
226  u32 pi0, lbi0;
227  ip_lookup_next_t next0;
228  load_balance_t *lb0;
229  ip6_address_t *dst_addr0;
230  u32 flow_hash_config0;
231  const dpo_id_t *dpo0;
232 
233  pi0 = from[0];
234  to_next[0] = pi0;
235 
236  p0 = vlib_get_buffer (vm, pi0);
237  ip0 = vlib_buffer_get_current (p0);
238  dst_addr0 = &ip0->dst_address;
240  lbi0 = ip6_fib_table_fwding_lookup (im,
241  vnet_buffer (p0)->ip.fib_index,
242  dst_addr0);
243 
244  lb0 = load_balance_get (lbi0);
245  flow_hash_config0 = lb0->lb_hash_config;
246 
247  vnet_buffer (p0)->ip.flow_hash = 0;
248  ASSERT (lb0->lb_n_buckets > 0);
249  ASSERT (is_pow2 (lb0->lb_n_buckets));
250 
251  if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
252  {
253  flow_hash_config0 = lb0->lb_hash_config;
254  vnet_buffer (p0)->ip.flow_hash =
255  ip6_compute_flow_hash (ip0, flow_hash_config0);
256  dpo0 =
258  (vnet_buffer (p0)->ip.flow_hash &
259  (lb0->lb_n_buckets_minus_1)));
260  }
261  else
262  {
263  dpo0 = load_balance_get_bucket_i (lb0, 0);
264  }
265 
266  dpo0 = load_balance_get_bucket_i (lb0,
267  (vnet_buffer (p0)->ip.flow_hash &
268  lb0->lb_n_buckets_minus_1));
269  next0 = dpo0->dpoi_next_node;
270 
271  /* Only process the HBH Option Header if explicitly configured to do so */
272  if (PREDICT_FALSE
273  (ip0->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS))
274  {
275  next0 = (dpo_is_adj (dpo0) && im->hbh_enabled) ?
277  }
278  vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
279 
281  (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
282 
283  from += 1;
284  to_next += 1;
285  n_left_to_next -= 1;
286  n_left_from -= 1;
287 
288  if (PREDICT_FALSE (next0 != next))
289  {
290  n_left_to_next += 1;
291  vlib_put_next_frame (vm, node, next, n_left_to_next);
292  next = next0;
293  vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
294  to_next[0] = pi0;
295  to_next += 1;
296  n_left_to_next -= 1;
297  }
298  }
299 
300  vlib_put_next_frame (vm, node, next, n_left_to_next);
301  }
302 
303  if (node->flags & VLIB_NODE_FLAG_TRACE)
304  ip6_forward_next_trace (vm, node, frame, VLIB_TX);
305 
306  return frame->n_vectors;
307 }
308 
309 #endif /*__included_ip6_forward_h__ */
310 
311 /*
312  * fd.io coding-style-patch-verification: ON
313  *
314  * Local Variables:
315  * eval: (c-set-style "gnu")
316  * End:
317  */
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:213
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)
u32 thread_index
Definition: main.h:176
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:250
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:184
unsigned int u32
Definition: types.h:88
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 void ip_lookup_set_buffer_fib_index(u32 *fib_index_by_sw_if_index, vlib_buffer_t *b)
Definition: lookup.h:215
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:202
static u32 ip6_compute_flow_hash(const ip6_header_t *ip, flow_hash_config_t flow_hash_config)
Definition: ip6.h:430
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:380
#define CLIB_PREFETCH(addr, size, type)
Definition: cache.h:77
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:492
#define ASSERT(truth)
ip6_main_t ip6_main
Definition: ip6_forward.c:2574
static load_balance_t * load_balance_get(index_t lbi)
Definition: load_balance.h:200
static uword is_pow2(uword x)
Definition: clib.h:229
Definition: defs.h:47
index_t dpoi_index
the index of objects of that type
Definition: dpo.h:184
u64 uword
Definition: types.h:112
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:181
#define vnet_buffer(b)
Definition: buffer.h:360
u8 data[0]
Packet data.
Definition: buffer.h:172
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:818
u16 flags
Copy of main node flags.
Definition: node.h:486
u16 dpoi_next_node
The next VLIB node to follow.
Definition: dpo.h:180
#define VLIB_NODE_FLAG_TRACE
Definition: node.h:295
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
ip6_address_t dst_address
Definition: ip6_packet.h:347