ip6.h revision 02833ff3
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.h: ip6 main include file
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_ip_ip6_h
41#define included_ip_ip6_h
42
43#include <vlib/buffer.h>
44#include <vnet/ethernet/packet.h>
45#include <vnet/ethernet/mac_address.h>
46#include <vnet/ip/ip6_packet.h>
47#include <vnet/ip/ip6_hop_by_hop_packet.h>
48#include <vnet/ip/lookup.h>
49#include <stdbool.h>
50#include <vppinfra/bihash_24_8.h>
51#include <vppinfra/bihash_40_8.h>
52#include <vppinfra/bihash_template.h>
53#include <vnet/util/radix.h>
54#include <vnet/util/throttle.h>
55
56/*
57 * Default size of the ip6 fib hash table
58 */
59#define IP6_FIB_DEFAULT_HASH_NUM_BUCKETS (64 * 1024)
60#define IP6_FIB_DEFAULT_HASH_MEMORY_SIZE (32<<20)
61
62typedef struct
63{
64  ip6_address_t addr;
65  u32 dst_address_length;
66  u32 vrf_index;
67} ip6_fib_key_t;
68
69typedef struct
70{
71  /* required for pool_get_aligned. */
72  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
73
74  /* Table ID (hash key) for this FIB. */
75  u32 table_id;
76
77  /* Index into FIB vector. */
78  u32 index;
79} ip6_fib_t;
80
81typedef struct ip6_mfib_t
82{
83  /* required for pool_get_aligned. */
84  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
85
86  /* Table ID (hash key) for this FIB. */
87  u32 table_id;
88
89  /* Index into FIB vector. */
90  u32 index;
91} ip6_mfib_t;
92
93struct ip6_main_t;
94
95typedef void (ip6_add_del_interface_address_function_t)
96  (struct ip6_main_t * im,
97   uword opaque,
98   u32 sw_if_index,
99   ip6_address_t * address,
100   u32 address_length, u32 if_address_index, u32 is_del);
101
102typedef struct
103{
104  ip6_add_del_interface_address_function_t *function;
105  uword function_opaque;
106} ip6_add_del_interface_address_callback_t;
107
108typedef void (ip6_table_bind_function_t)
109  (struct ip6_main_t * im,
110   uword opaque, u32 sw_if_index, u32 new_fib_index, u32 old_fib_index);
111
112typedef struct
113{
114  ip6_table_bind_function_t *function;
115  uword function_opaque;
116} ip6_table_bind_callback_t;
117
118/**
119 * Enumeration of the FIB table instance types
120 */
121typedef enum ip6_fib_table_instance_type_t_
122{
123    /**
124     * This table stores the routes that are used to forward traffic.
125     * The key is the prefix, the result the adjacency to forward on.
126     */
127  IP6_FIB_TABLE_FWDING,
128    /**
129     * The table that stores ALL routes learned by the DP.
130     * Some of these routes may not be ready to install in forwarding
131     * at a given time.
132     * The key in this table is the prefix, the result is the fib_entry_t
133     */
134  IP6_FIB_TABLE_NON_FWDING,
135} ip6_fib_table_instance_type_t;
136
137#define IP6_FIB_NUM_TABLES (IP6_FIB_TABLE_NON_FWDING+1)
138
139/**
140 * A representation of a single IP6 table
141 */
142typedef struct ip6_fib_table_instance_t_
143{
144  /* The hash table */
145  clib_bihash_24_8_t ip6_hash;
146
147  /* bitmap / refcounts / vector of mask widths to search */
148  uword *non_empty_dst_address_length_bitmap;
149  u8 *prefix_lengths_in_search_order;
150  i32 dst_address_length_refcounts[129];
151} ip6_fib_table_instance_t;
152
153/**
154 * A representation of a single IP6 mfib table
155 */
156typedef struct ip6_mfib_table_instance_t_
157{
158  /* The hash table */
159  clib_bihash_40_8_t ip6_mhash;
160
161  /* bitmap / refcounts / vector of mask widths to search */
162  uword *non_empty_dst_address_length_bitmap;
163  u16 *prefix_lengths_in_search_order;
164  i32 dst_address_length_refcounts[257];
165} ip6_mfib_table_instance_t;
166
167typedef struct ip6_main_t
168{
169  /**
170   * The two FIB tables; fwding and non-fwding
171   */
172  ip6_fib_table_instance_t ip6_table[IP6_FIB_NUM_TABLES];
173
174  /**
175   * the single MFIB table
176   */
177  ip6_mfib_table_instance_t ip6_mtable;
178
179  ip_lookup_main_t lookup_main;
180
181  /* Pool of FIBs. */
182  struct fib_table_t_ *fibs;
183
184  /* Pool of V6 FIBs. */
185  ip6_fib_t *v6_fibs;
186
187  /** Vector of MFIBs. */
188  struct mfib_table_t_ *mfibs;
189
190  /* Network byte orders subnet mask for each prefix length */
191  ip6_address_t fib_masks[129];
192
193  /* Table index indexed by software interface. */
194  u32 *fib_index_by_sw_if_index;
195
196  /** Table index indexed by software interface. */
197  u32 *mfib_index_by_sw_if_index;
198
199  /* IP6 enabled count by software interface */
200  u8 *ip_enabled_by_sw_if_index;
201
202  /* Hash table mapping table id to fib index.
203     ID space is not necessarily dense; index space is dense. */
204  uword *fib_index_by_table_id;
205
206  /** Hash table mapping table id to multicast fib index.
207     ID space is not necessarily dense; index space is dense. */
208  uword *mfib_index_by_table_id;
209
210  /* Hash table mapping interface rewrite adjacency index by sw if index. */
211  uword *interface_route_adj_index_by_sw_if_index;
212
213  /* Functions to call when interface address changes. */
214    ip6_add_del_interface_address_callback_t
215    * add_del_interface_address_callbacks;
216
217  /** Functions to call when interface to table biding changes. */
218  ip6_table_bind_callback_t *table_bind_callbacks;
219
220  /* Template used to generate IP6 neighbor solicitation packets. */
221  vlib_packet_template_t discover_neighbor_packet_template;
222
223  /* ip6 lookup table config parameters */
224  u32 lookup_table_nbuckets;
225  uword lookup_table_size;
226
227  /* Seed for Jenkins hash used to compute ip6 flow hash. */
228  u32 flow_hash_seed;
229
230  struct
231  {
232    /* TTL to use for host generated packets. */
233    u8 ttl;
234
235    u8 pad[3];
236  } host_config;
237
238  /* HBH processing enabled? */
239  u8 hbh_enabled;
240
241  /** ND throttling */
242  throttle_t nd_throttle;
243} ip6_main_t;
244
245#define ND_THROTTLE_BITS 512
246
247/* Global ip6 main structure. */
248extern ip6_main_t ip6_main;
249
250/* Global ip6 input node.  Errors get attached to ip6 input node. */
251extern vlib_node_registration_t ip6_input_node;
252extern vlib_node_registration_t ip6_rewrite_node;
253extern vlib_node_registration_t ip6_rewrite_mcast_node;
254extern vlib_node_registration_t ip6_rewrite_local_node;
255extern vlib_node_registration_t ip6_discover_neighbor_node;
256extern vlib_node_registration_t ip6_glean_node;
257extern vlib_node_registration_t ip6_midchain_node;
258
259extern void ip6_forward_next_trace (vlib_main_t * vm,
260				    vlib_node_runtime_t * node,
261				    vlib_frame_t * frame,
262				    vlib_rx_or_tx_t which_adj_index);
263
264always_inline uword
265ip6_destination_matches_route (const ip6_main_t * im,
266			       const ip6_address_t * key,
267			       const ip6_address_t * dest, uword dest_length)
268{
269  int i;
270  for (i = 0; i < ARRAY_LEN (key->as_uword); i++)
271    {
272      if ((key->as_uword[i] ^ dest->as_uword[i]) & im->
273	  fib_masks[dest_length].as_uword[i])
274	return 0;
275    }
276  return 1;
277}
278
279always_inline uword
280ip6_destination_matches_interface (ip6_main_t * im,
281				   ip6_address_t * key,
282				   ip_interface_address_t * ia)
283{
284  ip6_address_t *a = ip_interface_address_get_address (&im->lookup_main, ia);
285  return ip6_destination_matches_route (im, key, a, ia->address_length);
286}
287
288/* As above but allows for unaligned destinations (e.g. works right from IP header of packet). */
289always_inline uword
290ip6_unaligned_destination_matches_route (ip6_main_t * im,
291					 ip6_address_t * key,
292					 ip6_address_t * dest,
293					 uword dest_length)
294{
295  int i;
296  for (i = 0; i < ARRAY_LEN (key->as_uword); i++)
297    {
298      if ((clib_mem_unaligned (&key->as_uword[i], uword) ^ dest->as_uword[i])
299	  & im->fib_masks[dest_length].as_uword[i])
300	return 0;
301    }
302  return 1;
303}
304
305extern int ip6_get_ll_address (u32 sw_if_index, ip6_address_t * addr);
306
307always_inline int
308ip6_src_address_for_packet (ip_lookup_main_t * lm,
309			    u32 sw_if_index,
310			    const ip6_address_t * dst, ip6_address_t * src)
311{
312  if (ip6_address_is_link_local_unicast (dst))
313    {
314      return ip6_get_ll_address (sw_if_index, src);
315    }
316  else
317    {
318      u32 if_add_index =
319	lm->if_address_pool_index_by_sw_if_index[sw_if_index];
320      if (PREDICT_TRUE (if_add_index != ~0))
321	{
322	  ip_interface_address_t *if_add =
323	    pool_elt_at_index (lm->if_address_pool, if_add_index);
324	  ip6_address_t *if_ip =
325	    ip_interface_address_get_address (lm, if_add);
326	  *src = *if_ip;
327	  return (!0);
328	}
329    }
330
331  src->as_u64[0] = 0;
332  src->as_u64[1] = 0;
333
334  return (0);
335}
336
337/* Find interface address which matches destination. */
338always_inline ip6_address_t *
339ip6_interface_address_matching_destination (ip6_main_t * im,
340					    ip6_address_t * dst,
341					    u32 sw_if_index,
342					    ip_interface_address_t **
343					    result_ia)
344{
345  ip_lookup_main_t *lm = &im->lookup_main;
346  ip_interface_address_t *ia;
347  ip6_address_t *result = 0;
348
349  /* *INDENT-OFF* */
350  foreach_ip_interface_address (lm, ia, sw_if_index,
351                                1 /* honor unnumbered */,
352  ({
353    ip6_address_t * a = ip_interface_address_get_address (lm, ia);
354    if (ip6_destination_matches_route (im, dst, a, ia->address_length))
355      {
356	result = a;
357	break;
358      }
359  }));
360  /* *INDENT-ON* */
361  if (result_ia)
362    *result_ia = result ? ia : 0;
363  return result;
364}
365
366clib_error_t *ip6_add_del_interface_address (vlib_main_t * vm,
367					     u32 sw_if_index,
368					     ip6_address_t * address,
369					     u32 address_length, u32 is_del);
370void ip6_sw_interface_enable_disable (u32 sw_if_index, u32 is_enable);
371
372/**
373 * @brie get first IPv6 interface address
374 */
375ip6_address_t *ip6_interface_first_address (ip6_main_t * im, u32 sw_if_index);
376
377int ip6_address_compare (ip6_address_t * a1, ip6_address_t * a2);
378
379clib_error_t *ip6_probe_neighbor (vlib_main_t * vm, ip6_address_t * dst,
380				  u32 sw_if_index, u8 refresh);
381
382uword
383ip6_udp_register_listener (vlib_main_t * vm,
384			   u16 dst_port, u32 next_node_index);
385
386u16 ip6_tcp_udp_icmp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0,
387				       ip6_header_t * ip0,
388				       int *bogus_lengthp);
389
390void ip6_register_protocol (u32 protocol, u32 node_index);
391void ip6_unregister_protocol (u32 protocol);
392void ip6_local_hop_by_hop_register_protocol (u32 protocol, u32 node_index);
393
394serialize_function_t serialize_vnet_ip6_main, unserialize_vnet_ip6_main;
395
396void ip6_ethernet_update_adjacency (vnet_main_t * vnm,
397				    u32 sw_if_index, u32 ai);
398
399always_inline void
400ip6_link_local_address_from_ethernet_mac_address (ip6_address_t * ip,
401						  u8 * mac)
402{
403  ip->as_u64[0] = clib_host_to_net_u64 (0xFE80000000000000ULL);
404  /* Invert the "u" bit */
405  ip->as_u8[8] = mac[0] ^ (1 << 1);
406  ip->as_u8[9] = mac[1];
407  ip->as_u8[10] = mac[2];
408  ip->as_u8[11] = 0xFF;
409  ip->as_u8[12] = 0xFE;
410  ip->as_u8[13] = mac[3];
411  ip->as_u8[14] = mac[4];
412  ip->as_u8[15] = mac[5];
413}
414
415always_inline void
416ip6_ethernet_mac_address_from_link_local_address (u8 * mac,
417						  ip6_address_t * ip)
418{
419  /* Invert the previously inverted "u" bit */
420  mac[0] = ip->as_u8[8] ^ (1 << 1);
421  mac[1] = ip->as_u8[9];
422  mac[2] = ip->as_u8[10];
423  mac[3] = ip->as_u8[13];
424  mac[4] = ip->as_u8[14];
425  mac[5] = ip->as_u8[15];
426}
427
428int vnet_set_ip6_flow_hash (u32 table_id,
429			    flow_hash_config_t flow_hash_config);
430
431clib_error_t *enable_ip6_interface (vlib_main_t * vm, u32 sw_if_index);
432
433clib_error_t *disable_ip6_interface (vlib_main_t * vm, u32 sw_if_index);
434
435int ip6_interface_enabled (vlib_main_t * vm, u32 sw_if_index);
436
437clib_error_t *set_ip6_link_local_address (vlib_main_t * vm,
438					  u32 sw_if_index,
439					  ip6_address_t * address);
440
441typedef int (*ip6_nd_change_event_cb_t) (u32 pool_index,
442					 const mac_address_t * new_mac,
443					 u32 sw_if_index,
444					 const ip6_address_t * address);
445
446int vnet_add_del_ip6_nd_change_event (vnet_main_t * vnm,
447				      ip6_nd_change_event_cb_t data_callback,
448				      u32 pid,
449				      void *address_arg,
450				      uword node_index,
451				      uword type_opaque,
452				      uword data, int is_add);
453
454int vnet_ip6_nd_term (vlib_main_t * vm,
455		      vlib_node_runtime_t * node,
456		      vlib_buffer_t * p0,
457		      ethernet_header_t * eth,
458		      ip6_header_t * ip, u32 sw_if_index, u16 bd_index);
459
460void send_ip6_na (vlib_main_t * vm, u32 sw_if_index);
461void send_ip6_na_w_addr (vlib_main_t * vm,
462			 const ip6_address_t * addr, u32 sw_if_index);
463
464u8 *format_ip6_forward_next_trace (u8 * s, va_list * args);
465
466u32 ip6_tcp_udp_icmp_validate_checksum (vlib_main_t * vm, vlib_buffer_t * p0);
467
468void ip6_punt_policer_add_del (u8 is_add, u32 policer_index);
469void ip6_punt_redirect_add (u32 rx_sw_if_index,
470			    u32 tx_sw_if_index, ip46_address_t * nh);
471void ip6_punt_redirect_add_paths (u32 rx_sw_if_index,
472				  fib_route_path_t * paths);
473void ip6_punt_redirect_del (u32 rx_sw_if_index);
474
475int vnet_set_ip6_classify_intfc (vlib_main_t * vm, u32 sw_if_index,
476				 u32 table_index);
477extern vlib_node_registration_t ip6_lookup_node;
478
479/* Compute flow hash.  We'll use it to select which Sponge to use for this
480   flow.  And other things. */
481always_inline u32
482ip6_compute_flow_hash (const ip6_header_t * ip,
483		       flow_hash_config_t flow_hash_config)
484{
485  tcp_header_t *tcp;
486  u64 a, b, c;
487  u64 t1, t2;
488  uword is_tcp_udp = 0;
489  u8 protocol = ip->protocol;
490
491  if (PREDICT_TRUE
492      ((ip->protocol == IP_PROTOCOL_TCP)
493       || (ip->protocol == IP_PROTOCOL_UDP)))
494    {
495      is_tcp_udp = 1;
496      tcp = (void *) (ip + 1);
497    }
498  else if (ip->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS)
499    {
500      ip6_hop_by_hop_header_t *hbh = (ip6_hop_by_hop_header_t *) (ip + 1);
501      if ((hbh->protocol == IP_PROTOCOL_TCP) ||
502	  (hbh->protocol == IP_PROTOCOL_UDP))
503	{
504	  is_tcp_udp = 1;
505	  tcp = (tcp_header_t *) ((u8 *) hbh + ((hbh->length + 1) << 3));
506	}
507      protocol = hbh->protocol;
508    }
509
510  t1 = (ip->src_address.as_u64[0] ^ ip->src_address.as_u64[1]);
511  t1 = (flow_hash_config & IP_FLOW_HASH_SRC_ADDR) ? t1 : 0;
512
513  t2 = (ip->dst_address.as_u64[0] ^ ip->dst_address.as_u64[1]);
514  t2 = (flow_hash_config & IP_FLOW_HASH_DST_ADDR) ? t2 : 0;
515
516  a = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t2 : t1;
517  b = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t1 : t2;
518
519  t1 = is_tcp_udp ? tcp->src : 0;
520  t2 = is_tcp_udp ? tcp->dst : 0;
521
522  t1 = (flow_hash_config & IP_FLOW_HASH_SRC_PORT) ? t1 : 0;
523  t2 = (flow_hash_config & IP_FLOW_HASH_DST_PORT) ? t2 : 0;
524
525  if (flow_hash_config & IP_FLOW_HASH_SYMMETRIC)
526    {
527      if (b < a)
528	{
529	  c = a;
530	  a = b;
531	  b = c;
532	}
533      if (t2 < t1)
534	{
535	  t2 += t1;
536	  t1 = t2 - t1;
537	  t2 = t2 - t1;
538	}
539    }
540
541  b ^= (flow_hash_config & IP_FLOW_HASH_PROTO) ? protocol : 0;
542  c = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ?
543    ((t1 << 16) | t2) : ((t2 << 16) | t1);
544
545  hash_mix64 (a, b, c);
546  return (u32) c;
547}
548
549/* ip6_locate_header
550 *
551 * This function is to search for the header specified by the protocol number
552 * in find_hdr_type.
553 * This is used to locate a specific IPv6 extension header
554 * or to find transport layer header.
555 *   1. If the find_hdr_type < 0 then it finds and returns the protocol number and
556 *   offset stored in *offset of the transport or ESP header in the chain if
557 *   found.
558 *   2. If a header with find_hdr_type > 0 protocol number is found then the
559 *      offset is stored in *offset and protocol number of the header is
560 *      returned.
561 *   3. If find_hdr_type is not found or packet is malformed or
562 *      it is a non-first fragment -1 is returned.
563 */
564always_inline int
565ip6_locate_header (vlib_buffer_t * p0,
566		   ip6_header_t * ip0, int find_hdr_type, u32 * offset)
567{
568  u8 next_proto = ip0->protocol;
569  u8 *next_header;
570  u8 done = 0;
571  u32 cur_offset;
572  u8 *temp_nxthdr = 0;
573  u32 exthdr_len = 0;
574
575  next_header = ip6_next_header (ip0);
576  cur_offset = sizeof (ip6_header_t);
577  while (1)
578    {
579      done = (next_proto == find_hdr_type);
580      if (PREDICT_FALSE
581	  (next_header >=
582	   (u8 *) vlib_buffer_get_current (p0) + p0->current_length))
583	{
584	  //A malicious packet could set an extension header with a too big size
585	  return (-1);
586	}
587      if (done)
588	break;
589      if ((!ip6_ext_hdr (next_proto)) || next_proto == IP_PROTOCOL_IP6_NONXT)
590	{
591	  if (find_hdr_type < 0)
592	    break;
593	  return -1;
594	}
595      if (next_proto == IP_PROTOCOL_IPV6_FRAGMENTATION)
596	{
597	  ip6_frag_hdr_t *frag_hdr = (ip6_frag_hdr_t *) next_header;
598	  u16 frag_off = ip6_frag_hdr_offset (frag_hdr);
599	  /* Non first fragment return -1 */
600	  if (frag_off)
601	    return (-1);
602	  exthdr_len = sizeof (ip6_frag_hdr_t);
603	  temp_nxthdr = next_header + exthdr_len;
604	}
605      else if (next_proto == IP_PROTOCOL_IPSEC_AH)
606	{
607	  exthdr_len =
608	    ip6_ext_authhdr_len (((ip6_ext_header_t *) next_header));
609	  temp_nxthdr = next_header + exthdr_len;
610	}
611      else
612	{
613	  exthdr_len =
614	    ip6_ext_header_len (((ip6_ext_header_t *) next_header));
615	  temp_nxthdr = next_header + exthdr_len;
616	}
617      next_proto = ((ip6_ext_header_t *) next_header)->next_hdr;
618      next_header = temp_nxthdr;
619      cur_offset += exthdr_len;
620    }
621
622  *offset = cur_offset;
623  return (next_proto);
624}
625
626u8 *format_ip6_hop_by_hop_ext_hdr (u8 * s, va_list * args);
627/*
628 * Hop-by-Hop handling
629 */
630typedef struct
631{
632  /* Array of function pointers to HBH option handling routines */
633  int (*options[256]) (vlib_buffer_t * b, ip6_header_t * ip,
634		       ip6_hop_by_hop_option_t * opt);
635  u8 *(*trace[256]) (u8 * s, ip6_hop_by_hop_option_t * opt);
636  uword next_override;
637} ip6_hop_by_hop_main_t;
638
639extern ip6_hop_by_hop_main_t ip6_hop_by_hop_main;
640
641int ip6_hbh_register_option (u8 option,
642			     int options (vlib_buffer_t * b,
643					  ip6_header_t * ip,
644					  ip6_hop_by_hop_option_t * opt),
645			     u8 * trace (u8 * s,
646					 ip6_hop_by_hop_option_t * opt));
647int ip6_hbh_unregister_option (u8 option);
648void ip6_hbh_set_next_override (uword next);
649
650/**
651 * Push IPv6 header to buffer
652 *
653 * @param vm - vlib_main
654 * @param b - buffer to write the header to
655 * @param src - source IP
656 * @param dst - destination IP
657 * @param prot - payload proto
658 *
659 * @return - pointer to start of IP header
660 */
661always_inline void *
662vlib_buffer_push_ip6 (vlib_main_t * vm, vlib_buffer_t * b,
663		      ip6_address_t * src, ip6_address_t * dst, int proto)
664{
665  ip6_header_t *ip6h;
666  u16 payload_length;
667
668  /* make some room */
669  ip6h = vlib_buffer_push_uninit (b, sizeof (ip6_header_t));
670
671  ip6h->ip_version_traffic_class_and_flow_label =
672    clib_host_to_net_u32 (0x6 << 28);
673
674  /* calculate ip6 payload length */
675  payload_length = vlib_buffer_length_in_chain (vm, b);
676  payload_length -= sizeof (*ip6h);
677
678  ip6h->payload_length = clib_host_to_net_u16 (payload_length);
679
680  ip6h->hop_limit = 0xff;
681  ip6h->protocol = proto;
682  clib_memcpy_fast (ip6h->src_address.as_u8, src->as_u8,
683		    sizeof (ip6h->src_address));
684  clib_memcpy_fast (ip6h->dst_address.as_u8, dst->as_u8,
685		    sizeof (ip6h->src_address));
686  vnet_buffer (b)->l3_hdr_offset = (u8 *) ip6h - b->data;
687  b->flags |= VNET_BUFFER_F_IS_IP6 | VNET_BUFFER_F_L3_HDR_OFFSET_VALID;
688
689  return ip6h;
690}
691
692#endif /* included_ip_ip6_h */
693
694/*
695 * fd.io coding-style-patch-verification: ON
696 *
697 * Local Variables:
698 * eval: (c-set-style "gnu")
699 * End:
700 */
701