FD.io VPP  v18.10-34-gcce845e
Vector Packet Processing
adj.h
Go to the documentation of this file.
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  * An adjacency is a representation of an attached L3 peer.
17  *
18  * Adjacency Sub-types:
19  * - neighbour: a representation of an attached L3 peer.
20  * Key:{addr,interface,link/ether-type}
21  * SHARED
22  * - glean: used to drive ARP/ND for packets destined to a local sub-net.
23  * 'glean' mean use the packet's destination address as the target
24  * address in the ARP packet.
25  * UNSHARED. Only one per-interface.
26  * - midchain: a nighbour adj on a virtual/tunnel interface.
27  *
28  * The API to create and update the adjacency is very sub-type specific. This
29  * is intentional as it encourages the user to carefully consider which adjacency
30  * sub-type they are really using, and hence assign it data in the appropriate
31  * sub-type space in the union of sub-types. This prevents the adj becoming a
32  * disorganised dumping group for 'my features needs a u16 somewhere' data. It
33  * is important to enforce this approach as space in the adjacency is a premium,
34  * as we need it to fit in 1 cache line.
35  *
36  * the API is also based around an index to an ajdacency not a raw pointer. This
37  * is so the user doesn't suffer the same limp inducing firearm injuries that
38  * the author suffered as the adjacenices can realloc.
39  */
40 
41 #ifndef __ADJ_H__
42 #define __ADJ_H__
43 
44 #include <vnet/adj/adj_types.h>
45 #include <vnet/adj/adj_nbr.h>
46 #include <vnet/adj/adj_glean.h>
47 #include <vnet/adj/rewrite.h>
48 
49 /** @brief Common (IP4/IP6) next index stored in adjacency. */
50 typedef enum
51 {
52  /** Adjacency to drop this packet. */
54  /** Adjacency to punt this packet. */
56 
57  /** This packet is for one of our own IP addresses. */
59 
60  /** This packet matches an "incomplete adjacency" and packets
61  need to be passed to ARP to find rewrite string for
62  this destination. */
64 
65  /** This packet matches an "interface route" and packets
66  need to be passed to ARP to find rewrite string for
67  this destination. */
69 
70  /** This packet is to be rewritten and forwarded to the next
71  processing node. This is typically the output interface but
72  might be another node for further output processing. */
74 
75  /** This packets follow a mid-chain adjacency */
77 
78  /** This packets needs to go to ICMP error */
80 
81  /** Multicast Adjacency. */
83 
84  /** Broadcasr Adjacency. */
86 
87  /** Multicast Midchain Adjacency. An Adjacency for sending macst packets
88  * on a tunnel/virtual interface */
90 
92 } __attribute__ ((packed)) ip_lookup_next_t;
93 
94 typedef enum
95 {
98 
99 typedef enum
100 {
101  /* Hop-by-hop header handling */
107 
108 #define IP4_LOOKUP_NEXT_NODES { \
109  [IP_LOOKUP_NEXT_DROP] = "ip4-drop", \
110  [IP_LOOKUP_NEXT_PUNT] = "ip4-punt", \
111  [IP_LOOKUP_NEXT_LOCAL] = "ip4-local", \
112  [IP_LOOKUP_NEXT_ARP] = "ip4-arp", \
113  [IP_LOOKUP_NEXT_GLEAN] = "ip4-glean", \
114  [IP_LOOKUP_NEXT_REWRITE] = "ip4-rewrite", \
115  [IP_LOOKUP_NEXT_MCAST] = "ip4-rewrite-mcast", \
116  [IP_LOOKUP_NEXT_BCAST] = "ip4-rewrite-bcast", \
117  [IP_LOOKUP_NEXT_MIDCHAIN] = "ip4-midchain", \
118  [IP_LOOKUP_NEXT_MCAST_MIDCHAIN] = "ip4-mcast-midchain", \
119  [IP_LOOKUP_NEXT_ICMP_ERROR] = "ip4-icmp-error", \
120 }
121 
122 #define IP6_LOOKUP_NEXT_NODES { \
123  [IP_LOOKUP_NEXT_DROP] = "ip6-drop", \
124  [IP_LOOKUP_NEXT_PUNT] = "ip6-punt", \
125  [IP_LOOKUP_NEXT_LOCAL] = "ip6-local", \
126  [IP_LOOKUP_NEXT_ARP] = "ip6-discover-neighbor", \
127  [IP_LOOKUP_NEXT_GLEAN] = "ip6-glean", \
128  [IP_LOOKUP_NEXT_REWRITE] = "ip6-rewrite", \
129  [IP_LOOKUP_NEXT_BCAST] = "ip6-rewrite-bcast", \
130  [IP_LOOKUP_NEXT_MCAST] = "ip6-rewrite-mcast", \
131  [IP_LOOKUP_NEXT_MIDCHAIN] = "ip6-midchain", \
132  [IP_LOOKUP_NEXT_MCAST_MIDCHAIN] = "ip6-mcast-midchain", \
133  [IP_LOOKUP_NEXT_ICMP_ERROR] = "ip6-icmp-error", \
134  [IP6_LOOKUP_NEXT_HOP_BY_HOP] = "ip6-hop-by-hop", \
135  [IP6_LOOKUP_NEXT_ADD_HOP_BY_HOP] = "ip6-add-hop-by-hop", \
136  [IP6_LOOKUP_NEXT_POP_HOP_BY_HOP] = "ip6-pop-hop-by-hop", \
137 }
138 
139 /**
140  * The special broadcast address (to construct a broadcast adjacency
141  */
142 extern const ip46_address_t ADJ_BCAST_ADDR;
143 
144 /**
145  * Forward delcartion
146  */
147 struct ip_adjacency_t_;
148 
149 /**
150  * @brief A function type for post-rewrite fixups on midchain adjacency
151  */
153  struct ip_adjacency_t_ * adj,
154  vlib_buffer_t * b0,
155  const void *data);
156 
157 /**
158  * @brief Flags on an IP adjacency
159  */
161 {
163 
164  /**
165  * Currently a sync walk is active. Used to prevent re-entrant walking
166  */
168 
169  /**
170  * Packets TX through the midchain do not increment the interface
171  * counters. This should be used when the adj is associated with an L2
172  * interface and that L2 interface is in a bridege domain. In that case
173  * the packet will have traversed the interface's TX node, and hence have
174  * been counted, before it traverses ths midchain
175  */
177 } __attribute__ ((packed)) adj_flags_t;
178 
179 /**
180  * @brief IP unicast adjacency.
181  * @note cache aligned.
182  *
183  * An adjacency is a represenation of a peer on a particular link.
184  */
185 typedef struct ip_adjacency_t_
186 {
187  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
188 
189  /**
190  * Linkage into the FIB node grpah. First member since this type
191  * has 8 byte alignment requirements.
192  */
194 
195  /**
196  * Next hop after ip4-lookup.
197  * This is not accessed in the rewrite nodes.
198  * 1-bytes
199  */
201 
202  /**
203  * link/ether-type
204  * 1 bytes
205  */
207 
208  /**
209  * The protocol of the neighbor/peer. i.e. the protocol with
210  * which to interpret the 'next-hop' attirbutes of the sub-types.
211  * 1-btyes
212  */
214 
215  /**
216  * Flags on the adjacency
217  * 1-bytes
218  */
219  adj_flags_t ia_flags;
220 
221  union
222  {
223  /**
224  * IP_LOOKUP_NEXT_ARP/IP_LOOKUP_NEXT_REWRITE
225  *
226  * neighbour adjacency sub-type;
227  */
228  struct
229  {
230  ip46_address_t next_hop;
231  } nbr;
232  /**
233  * IP_LOOKUP_NEXT_MIDCHAIN
234  *
235  * A nbr adj that is also recursive. Think tunnels.
236  * A nbr adj can transition to be of type MDICHAIN
237  * so be sure to leave the two structs with the next_hop
238  * fields aligned.
239  */
240  struct
241  {
242  /**
243  * The recursive next-hop.
244  * This field MUST be at the same memory location as
245  * sub_type.nbr.next_hop
246  */
247  ip46_address_t next_hop;
248  /**
249  * The next DPO to use
250  */
252  /**
253  * A function to perform the post-rewrite fixup
254  */
256  /**
257  * Fixup data passed back to the client in the fixup function
258  */
259  const void *fixup_data;
260  } midchain;
261  /**
262  * IP_LOOKUP_NEXT_GLEAN
263  *
264  * Glean the address to ARP for from the packet's destination.
265  * Technically these aren't adjacencies, i.e. they are not a
266  * representation of a peer. One day we might untangle this coupling
267  * and use a new Glean DPO.
268  */
269  struct
270  {
271  ip46_address_t receive_addr;
272  } glean;
273  } sub_type;
274 
275  CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
276 
277  /* Rewrite in second/third cache lines */
279 
280  /**
281  * more control plane members that do not fit on the first cacheline
282  */
283  /**
284  * A sorted vector of delegates
285  */
287 
289 
290 STATIC_ASSERT ((STRUCT_OFFSET_OF (ip_adjacency_t, cacheline0) == 0),
291  "IP adjacency cachline 0 is not offset");
294  "IP adjacency cachline 1 is more than one cachline size offset");
295 
296 /**
297  * @brief
298  * Take a reference counting lock on the adjacency
299  */
300 extern void adj_lock(adj_index_t adj_index);
301 /**
302  * @brief
303  * Release a reference counting lock on the adjacency
304  */
305 extern void adj_unlock(adj_index_t adj_index);
306 
307 /**
308  * @brief
309  * Add a child dependent to an adjacency. The child will
310  * thus be informed via its registerd back-walk function
311  * when the adjacency state changes.
312  */
313 extern u32 adj_child_add(adj_index_t adj_index,
314  fib_node_type_t type,
315  fib_node_index_t child_index);
316 /**
317  * @brief
318  * Remove a child dependent
319  */
320 extern void adj_child_remove(adj_index_t adj_index,
321  u32 sibling_index);
322 
323 /**
324  * @brief Walk the Adjacencies on a given interface
325  */
326 extern void adj_walk (u32 sw_if_index,
327  adj_walk_cb_t cb,
328  void *ctx);
329 
330 /**
331  * @brief Return the link type of the adjacency
332  */
334 
335 /**
336  * @brief Return the sw interface index of the adjacency.
337  */
339 
340 /**
341  * @brief Return true if the adjacency is 'UP', i.e. can be used for forwarding.
342  * 0 is down, !0 is up.
343  */
344 extern int adj_is_up (adj_index_t ai);
345 
346 /**
347  * @brief Return the link type of the adjacency
348  */
349 extern const u8* adj_get_rewrite (adj_index_t ai);
350 
351 /**
352  * @brief Notify the adjacency subsystem that the features settings for
353  * an interface have changed
354  */
355 extern void adj_feature_update (u32 sw_if_index, u8 arc_index, u8 is_enable);
356 
357 /**
358  * @brief
359  * The global adjacnecy pool. Exposed for fast/inline data-plane access
360  */
361 extern ip_adjacency_t *adj_pool;
362 
363 /**
364  * @brief
365  * Adjacency packet counters
366  */
368 
369 /**
370  * @brief Global Config for enabling per-adjacency counters
371  * This is configurable because it comes with a non-negligible
372  * performance cost. */
373 extern int adj_per_adj_counters;
374 
375 /**
376  * @brief
377  * Get a pointer to an adjacency object from its index
378  */
379 static inline ip_adjacency_t *
380 adj_get (adj_index_t adj_index)
381 {
382  return (vec_elt_at_index(adj_pool, adj_index));
383 }
384 
385 /**
386  * @brief Get the global configuration option for enabling per-adj counters
387  */
388 static inline int
390 {
391  return (adj_per_adj_counters);
392 }
393 
394 #endif
int adj_is_up(adj_index_t ai)
Return true if the adjacency is &#39;UP&#39;, i.e.
Definition: adj.c:427
adj_flags_t ia_flags
Flags on the adjacency 1-bytes.
Definition: adj.h:219
#define CLIB_CACHE_LINE_ALIGN_MARK(mark)
Definition: cache.h:60
struct ip_adjacency_t_::@45::@47 midchain
IP_LOOKUP_NEXT_MIDCHAIN.
u32 adj_child_add(adj_index_t adj_index, fib_node_type_t type, fib_node_index_t child_index)
Add a child dependent to an adjacency.
Definition: adj.c:271
struct ip_adjacency_t_::@45::@46 nbr
IP_LOOKUP_NEXT_ARP/IP_LOOKUP_NEXT_REWRITE.
ip_adjacency_flags_t_
Flags on an IP adjacency.
Definition: adj.h:160
Multicast Adjacency.
Definition: adj.h:82
Broadcasr Adjacency.
Definition: adj.h:85
IP unicast adjacency.
Definition: adj.h:185
union ip_adjacency_t_::@45 sub_type
#define VLIB_BUFFER_PRE_DATA_SIZE
Definition: buffer.h:52
This packet is to be rewritten and forwarded to the next processing node.
Definition: adj.h:73
#define STRUCT_OFFSET_OF(t, f)
Definition: clib.h:64
const ip46_address_t ADJ_BCAST_ADDR
The special broadcast address (to construct a broadcast adjacency.
Definition: adj.c:41
adj_midchain_fixup_t fixup_func
A function to perform the post-rewrite fixup.
Definition: adj.h:255
unsigned char u8
Definition: types.h:56
ip_lookup_next_t
An adjacency is a representation of an attached L3 peer.
Definition: adj.h:50
void adj_walk(u32 sw_if_index, adj_walk_cb_t cb, void *ctx)
Walk the Adjacencies on a given interface.
Definition: adj.c:380
enum fib_protocol_t_ fib_protocol_t
Protocol Type.
struct ip_adjacency_t_ ip_adjacency_t
IP unicast adjacency.
vnet_link_t ia_link
link/ether-type 1 bytes
Definition: adj.h:206
Adjacency to punt this packet.
Definition: adj.h:55
ip46_address_t receive_addr
Definition: adj.h:271
static ip_adjacency_t * adj_get(adj_index_t adj_index)
Get a pointer to an adjacency object from its index.
Definition: adj.h:380
enum ip_adjacency_flags_t_ adj_flags_t
Flags on an IP adjacency.
u32 sw_if_index
Definition: vxlan_gbp.api:39
ip6_lookup_next_t
Definition: adj.h:99
#define vec_elt_at_index(v, i)
Get vector value at index i checking that i is in bounds.
ip46_address_t next_hop
The recursive next-hop.
Definition: adj.h:230
Adj delegate.
Definition: adj_delegate.h:44
unsigned int u32
Definition: types.h:88
struct ip_adjacency_t_::@45::@48 glean
IP_LOOKUP_NEXT_GLEAN.
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
dpo_id_t next_dpo
The next DPO to use.
Definition: adj.h:251
long ctx[MAX_CONNS]
Definition: main.c:144
ip_adjacency_t * adj_pool
The global adjacnecy pool.
Definition: adj.c:33
This packet matches an "interface route" and packets need to be passed to ARP to find rewrite string ...
Definition: adj.h:68
void adj_lock(adj_index_t adj_index)
Take a reference counting lock on the adjacency.
Definition: adj.c:235
An node in the FIB graph.
Definition: fib_node.h:289
fib_node_t ia_node
Linkage into the FIB node grpah.
Definition: adj.h:193
const u8 * adj_get_rewrite(adj_index_t ai)
Return the link type of the adjacency.
Definition: adj.c:436
Currently a sync walk is active.
Definition: adj.h:167
This packet matches an "incomplete adjacency" and packets need to be passed to ARP to find rewrite st...
Definition: adj.h:63
Adjacency to drop this packet.
Definition: adj.h:53
vlib_main_t * vm
Definition: buffer.c:294
Multicast Midchain Adjacency.
Definition: adj.h:89
Packets TX through the midchain do not increment the interface counters.
Definition: adj.h:176
u32 fib_node_index_t
A typedef of a node index.
Definition: fib_types.h:30
adj_walk_rc_t(* adj_walk_cb_t)(adj_index_t ai, void *ctx)
Call back function when walking adjacencies.
Definition: adj_types.h:50
void(* adj_midchain_fixup_t)(vlib_main_t *vm, struct ip_adjacency_t_ *adj, vlib_buffer_t *b0, const void *data)
A function type for post-rewrite fixups on midchain adjacency.
Definition: adj.h:152
u32 adj_index_t
An index for adjacencies.
Definition: adj_types.h:30
void adj_feature_update(u32 sw_if_index, u8 arc_index, u8 is_enable)
Notify the adjacency subsystem that the features settings for an interface have changed.
Definition: adj.c:339
This packets follow a mid-chain adjacency.
Definition: adj.h:76
enum vnet_link_t_ vnet_link_t
Link Type: A description of the protocol of packets on the link.
vnet_link_t adj_get_link_type(adj_index_t ai)
Return the link type of the adjacency.
Definition: adj.c:400
const void * fixup_data
Fixup data passed back to the client in the fixup function.
Definition: adj.h:259
vlib_combined_counter_main_t adjacency_counters
Adjacency packet counters.
Definition: adj.c:25
This packets needs to go to ICMP error.
Definition: adj.h:79
This packet is for one of our own IP addresses.
Definition: adj.h:58
fib_protocol_t ia_nh_proto
The protocol of the neighbor/peer.
Definition: adj.h:213
ip4_lookup_next_t
Definition: adj.h:94
#define vnet_declare_rewrite(total_bytes)
Definition: rewrite.h:108
ip_lookup_next_t lookup_next_index
Next hop after ip4-lookup.
Definition: adj.h:200
void adj_child_remove(adj_index_t adj_index, u32 sibling_index)
Remove a child dependent.
Definition: adj.c:288
u32 adj_get_sw_if_index(adj_index_t ai)
Return the sw interface index of the adjacency.
Definition: adj.c:413
A collection of combined counters.
Definition: counter.h:172
STATIC_ASSERT((STRUCT_OFFSET_OF(ip_adjacency_t, cacheline0)==0),"IP adjacency cachline 0 is not offset")
enum fib_node_type_t_ fib_node_type_t
The types of nodes in a FIB graph.
int adj_per_adj_counters
Global Config for enabling per-adjacency counters This is configurable because it comes with a non-ne...
Definition: adj.c:39
#define CLIB_CACHE_LINE_BYTES
Definition: cache.h:59
void adj_unlock(adj_index_t adj_index)
Release a reference counting lock on the adjacency.
Definition: adj.c:252
static int adj_are_counters_enabled(void)
Get the global configuration option for enabling per-adj counters.
Definition: adj.h:389
struct adj_delegate_t_ * ia_delegates
more control plane members that do not fit on the first cacheline
Definition: adj.h:286