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Vector Packet Processing
ip6_to_ip4.h
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1 /*
2  * Copyright (c) 2017 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  * @file
17  * @brief IPv6 to IPv4 translation
18  */
19 #ifndef __included_ip6_to_ip4_h__
20 #define __included_ip6_to_ip4_h__
21 
22 #include <vnet/ip/ip.h>
23 
24 /**
25  * IPv6 to IPv4 set call back function type
26  */
27 typedef int (*ip6_to_ip4_set_fn_t) (ip6_header_t * ip6, ip4_header_t * ip4,
28  void *ctx);
29 
30 /* *INDENT-OFF* */
32  { 0, 1, ~0, ~0,
33  2, 2, 9, 8,
34  12, 12, 12, 12,
35  12, 12, 12, 12,
36  12, 12, 12, 12,
37  12, 12, 12, 12,
38  24, 24, 24, 24,
39  24, 24, 24, 24,
40  24, 24, 24, 24,
41  24, 24, 24, 24
42  };
43 /* *INDENT-ON* */
44 
45 #define frag_id_6to4(id) ((id) ^ ((id) >> 16))
46 
47 /**
48  * @brief Parse some useful information from IPv6 header.
49  *
50  * @param ip6 IPv6 header.
51  * @param buff_len Buffer length.
52  * @param l4_protocol L4 protocol number.
53  * @param l4_offset L4 header offset.
54  * @param frag_hdr_offset Fragment header offset if present, 0 otherwise.
55  *
56  * @returns 0 on success, non-zero value otherwise.
57  */
59 ip6_parse (const ip6_header_t * ip6, u32 buff_len,
60  u8 * l4_protocol, u16 * l4_offset, u16 * frag_hdr_offset)
61 {
62  if (ip6->protocol == IP_PROTOCOL_IPV6_FRAGMENTATION)
63  {
64  *l4_protocol = ((ip6_frag_hdr_t *) (ip6 + 1))->next_hdr;
65  *frag_hdr_offset = sizeof (*ip6);
66  *l4_offset = sizeof (*ip6) + sizeof (ip6_frag_hdr_t);
67  }
68  else
69  {
70  *l4_protocol = ip6->protocol;
71  *frag_hdr_offset = 0;
72  *l4_offset = sizeof (*ip6);
73  }
74 
75  return (buff_len < (*l4_offset + 4)) ||
76  (clib_net_to_host_u16 (ip6->payload_length) <
77  (*l4_offset + 4 - sizeof (*ip6)));
78 }
79 
80 /**
81  * @brief Get TCP/UDP port number or ICMP id from IPv6 packet.
82  *
83  * @param ip6 IPv6 header.
84  * @param sender 1 get sender port, 0 get receiver port.
85  * @param buffer_len Buffer length.
86  *
87  * @returns Port number on success, 0 otherwise.
88  */
90 ip6_get_port (ip6_header_t * ip6, u8 sender, u16 buffer_len)
91 {
92  u8 l4_protocol;
93  u16 l4_offset;
94  u16 frag_offset;
95  u8 *l4;
96 
97  if (ip6_parse (ip6, buffer_len, &l4_protocol, &l4_offset, &frag_offset))
98  return 0;
99 
100  if (frag_offset &&
101  ip6_frag_hdr_offset (((ip6_frag_hdr_t *)
102  u8_ptr_add (ip6, frag_offset))))
103  return 0; //Can't deal with non-first fragment for now
104 
105  l4 = u8_ptr_add (ip6, l4_offset);
106  if (l4_protocol == IP_PROTOCOL_TCP || l4_protocol == IP_PROTOCOL_UDP)
107  {
108  return (sender) ? ((udp_header_t *) (l4))->src_port : ((udp_header_t
109  *)
110  (l4))->dst_port;
111  }
112  else if (l4_protocol == IP_PROTOCOL_ICMP6)
113  {
114  icmp46_header_t *icmp = (icmp46_header_t *) (l4);
115  if (icmp->type == ICMP6_echo_request)
116  {
117  return (sender) ? ((u16 *) (icmp))[2] : -1;
118  }
119  else if (icmp->type == ICMP6_echo_reply)
120  {
121  return (sender) ? -1 : ((u16 *) (icmp))[2];
122  }
123  }
124  return 0;
125 }
126 
127 /**
128  * @brief Convert type and code value from ICMP6 to ICMP4.
129  *
130  * @param icmp ICMP header.
131  * @param inner_ip6 Inner IPv6 header if present, 0 otherwise.
132  *
133  * @returns 0 on success, non-zero value otherwise.
134  */
136 icmp6_to_icmp_header (icmp46_header_t * icmp, ip6_header_t ** inner_ip6)
137 {
138  *inner_ip6 = NULL;
139  switch (icmp->type)
140  {
141  case ICMP6_echo_request:
142  icmp->type = ICMP4_echo_request;
143  break;
144  case ICMP6_echo_reply:
145  icmp->type = ICMP4_echo_reply;
146  break;
147  case ICMP6_destination_unreachable:
148  *inner_ip6 = (ip6_header_t *) u8_ptr_add (icmp, 8);
149 
150  switch (icmp->code)
151  {
152  case ICMP6_destination_unreachable_no_route_to_destination: //0
153  case ICMP6_destination_unreachable_beyond_scope_of_source_address: //2
154  case ICMP6_destination_unreachable_address_unreachable: //3
155  icmp->type = ICMP4_destination_unreachable;
156  icmp->code =
157  ICMP4_destination_unreachable_destination_unreachable_host;
158  break;
159  case ICMP6_destination_unreachable_destination_administratively_prohibited: //1
160  icmp->type =
161  ICMP4_destination_unreachable;
162  icmp->code =
163  ICMP4_destination_unreachable_communication_administratively_prohibited;
164  break;
165  case ICMP6_destination_unreachable_port_unreachable:
166  icmp->type = ICMP4_destination_unreachable;
167  icmp->code = ICMP4_destination_unreachable_port_unreachable;
168  break;
169  default:
170  return -1;
171  }
172  break;
173  case ICMP6_packet_too_big:
174  *inner_ip6 = (ip6_header_t *) u8_ptr_add (icmp, 8);
175 
176  icmp->type = ICMP4_destination_unreachable;
177  icmp->code = 4;
178  {
179  u32 advertised_mtu = clib_net_to_host_u32 (*((u32 *) (icmp + 1)));
180  advertised_mtu -= 20;
181  //FIXME: = minimum(advertised MTU-20, MTU_of_IPv4_nexthop, (MTU_of_IPv6_nexthop)-20)
182  ((u16 *) (icmp))[3] = clib_host_to_net_u16 (advertised_mtu);
183  }
184  break;
185 
186  case ICMP6_time_exceeded:
187  *inner_ip6 = (ip6_header_t *) u8_ptr_add (icmp, 8);
188 
189  icmp->type = ICMP4_time_exceeded;
190  break;
191 
192  case ICMP6_parameter_problem:
193  *inner_ip6 = (ip6_header_t *) u8_ptr_add (icmp, 8);
194 
195  switch (icmp->code)
196  {
197  case ICMP6_parameter_problem_erroneous_header_field:
198  icmp->type = ICMP4_parameter_problem;
199  icmp->code = ICMP4_parameter_problem_pointer_indicates_error;
200  u32 pointer = clib_net_to_host_u32 (*((u32 *) (icmp + 1)));
201  if (pointer >= 40)
202  return -1;
203 
204  ((u8 *) (icmp + 1))[0] =
206  break;
207  case ICMP6_parameter_problem_unrecognized_next_header:
208  icmp->type = ICMP4_destination_unreachable;
209  icmp->code = ICMP4_destination_unreachable_port_unreachable;
210  break;
211  case ICMP6_parameter_problem_unrecognized_option:
212  default:
213  return -1;
214  }
215  break;
216  default:
217  return -1;
218  break;
219  }
220  return 0;
221 }
222 
223 /**
224  * @brief Translate TOS value from IPv6 to IPv4.
225  *
226  * @param ip6 IPv6 header.
227  *
228  * @returns IPv4 TOS value.
229  */
232 {
233  return (clib_net_to_host_u32 (ip6->ip_version_traffic_class_and_flow_label)
234  & 0x0ff00000) >> 20;
235 }
236 
237 /**
238  * @brief Translate ICMP6 packet to ICMP4.
239  *
240  * @param p Buffer to translate.
241  * @param fn The function to translate outer header.
242  * @param ctx A context passed in the outer header translate function.
243  * @param inner_fn The function to translate inner header.
244  * @param inner_ctx A context passed in the inner header translate function.
245  *
246  * @returns 0 on success, non-zero value otherwise.
247  */
248 always_inline int
250  ip6_to_ip4_set_fn_t inner_fn, void *inner_ctx)
251 {
252  ip6_header_t *ip6, *inner_ip6;
253  ip4_header_t *ip4, *inner_ip4;
254  u32 ip6_pay_len;
255  icmp46_header_t *icmp;
256  ip_csum_t csum;
257  int rv;
258  ip6_address_t old_src, old_dst;
259 
260  ip6 = vlib_buffer_get_current (p);
261  ip6_pay_len = clib_net_to_host_u16 (ip6->payload_length);
262  icmp = (icmp46_header_t *) (ip6 + 1);
263  ASSERT (ip6_pay_len + sizeof (*ip6) <= p->current_length);
264 
265  //No extensions headers allowed here
266  if (ip6->protocol != IP_PROTOCOL_ICMP6)
267  return -1;
268 
269  //There are no fragmented ICMP messages, so no extension header for now
270  if (icmp6_to_icmp_header (icmp, &inner_ip6))
271  return -1;
272 
273  if (inner_ip6)
274  {
275  u16 *inner_L4_checksum, inner_l4_offset, inner_frag_offset,
276  inner_frag_id;
277  u8 *inner_l4, inner_protocol;
278 
279  //We have two headers to translate
280  // FROM
281  // [ IPv6 ]<- ext ->[IC][ IPv6 ]<- ext ->[L4 header ...
282  // Handled cases:
283  // [ IPv6 ][IC][ IPv6 ][L4 header ...
284  // [ IPv6 ][IC][ IPv6 ][Fr][L4 header ...
285  // TO
286  // [ IPv4][IC][ IPv4][L4 header ...
287 
288  if (ip6_parse (inner_ip6, ip6_pay_len - 8,
289  &inner_protocol, &inner_l4_offset, &inner_frag_offset))
290  return -1;
291 
292  inner_l4 = u8_ptr_add (inner_ip6, inner_l4_offset);
293  inner_ip4 =
294  (ip4_header_t *) u8_ptr_add (inner_l4, -sizeof (*inner_ip4));
295  if (inner_frag_offset)
296  {
297  ip6_frag_hdr_t *inner_frag =
298  (ip6_frag_hdr_t *) u8_ptr_add (inner_ip6, inner_frag_offset);
299  inner_frag_id = frag_id_6to4 (inner_frag->identification);
300  }
301  else
302  {
303  inner_frag_id = 0;
304  }
305 
306  //Do the translation of the inner packet
307  if (inner_protocol == IP_PROTOCOL_TCP)
308  {
309  inner_L4_checksum = (u16 *) u8_ptr_add (inner_l4, 16);
310  }
311  else if (inner_protocol == IP_PROTOCOL_UDP)
312  {
313  inner_L4_checksum = (u16 *) u8_ptr_add (inner_l4, 6);
314  }
315  else if (inner_protocol == IP_PROTOCOL_ICMP6)
316  {
317  icmp46_header_t *inner_icmp = (icmp46_header_t *) inner_l4;
318  //It cannot be of a different type as ip6_icmp_to_icmp6_in_place succeeded
319  inner_icmp->type = (inner_icmp->type == ICMP6_echo_request) ?
320  ICMP4_echo_request : ICMP4_echo_reply;
321  inner_protocol = IP_PROTOCOL_ICMP; //Will be copied to ip6 later
322  inner_L4_checksum = &inner_icmp->checksum;
323  }
324  else
325  {
326  return -1;
327  }
328 
329  old_src.as_u64[0] = inner_ip6->src_address.as_u64[0];
330  old_src.as_u64[1] = inner_ip6->src_address.as_u64[1];
331  old_dst.as_u64[0] = inner_ip6->dst_address.as_u64[0];
332  old_dst.as_u64[1] = inner_ip6->dst_address.as_u64[1];
333 
334  if ((rv = inner_fn (inner_ip6, inner_ip4, inner_ctx)) != 0)
335  return rv;
336 
337  inner_ip4->ip_version_and_header_length =
339  inner_ip4->tos = ip6_translate_tos (inner_ip6);
340  inner_ip4->length =
341  u16_net_add (inner_ip6->payload_length,
342  sizeof (*ip4) + sizeof (*ip6) - inner_l4_offset);
343  inner_ip4->fragment_id = inner_frag_id;
344  inner_ip4->flags_and_fragment_offset =
345  clib_host_to_net_u16 (IP4_HEADER_FLAG_MORE_FRAGMENTS);
346  inner_ip4->ttl = inner_ip6->hop_limit;
347  inner_ip4->protocol = inner_protocol;
348  inner_ip4->checksum = ip4_header_checksum (inner_ip4);
349 
350  if (inner_ip4->protocol == IP_PROTOCOL_ICMP)
351  {
352  //Recompute ICMP checksum
353  icmp46_header_t *inner_icmp = (icmp46_header_t *) inner_l4;
354  inner_icmp->checksum = 0;
355  csum =
356  ip_incremental_checksum (0, inner_icmp,
357  clib_net_to_host_u16 (inner_ip4->length)
358  - sizeof (*inner_ip4));
359  inner_icmp->checksum = ~ip_csum_fold (csum);
360  }
361  else
362  {
363  //Update to new pseudo-header
364  csum = *inner_L4_checksum;
365  csum = ip_csum_sub_even (csum, old_src.as_u64[0]);
366  csum = ip_csum_sub_even (csum, old_src.as_u64[1]);
367  csum = ip_csum_sub_even (csum, old_dst.as_u64[0]);
368  csum = ip_csum_sub_even (csum, old_dst.as_u64[1]);
369  csum = ip_csum_add_even (csum, inner_ip4->src_address.as_u32);
370  csum = ip_csum_add_even (csum, inner_ip4->dst_address.as_u32);
371  *inner_L4_checksum = ip_csum_fold (csum);
372  }
373 
374  //Move up icmp header
375  ip4 = (ip4_header_t *) u8_ptr_add (inner_l4, -2 * sizeof (*ip4) - 8);
376  clib_memcpy_fast (u8_ptr_add (inner_l4, -sizeof (*ip4) - 8), icmp, 8);
377  icmp = (icmp46_header_t *) u8_ptr_add (inner_l4, -sizeof (*ip4) - 8);
378  }
379  else
380  {
381  //Only one header to translate
382  ip4 = (ip4_header_t *) u8_ptr_add (ip6, sizeof (*ip6) - sizeof (*ip4));
383  }
384 
385  vlib_buffer_advance (p, (u32) (((u8 *) ip4) - ((u8 *) ip6)));
386 
387  if ((rv = fn (ip6, ip4, ctx)) != 0)
388  return rv;
389 
392  ip4->tos = ip6_translate_tos (ip6);
393  ip4->fragment_id = 0;
394  ip4->flags_and_fragment_offset = 0;
395  ip4->ttl = ip6->hop_limit;
396  ip4->protocol = IP_PROTOCOL_ICMP;
397  //TODO fix the length depending on offset length
398  ip4->length = u16_net_add (ip6->payload_length,
399  (inner_ip6 ==
400  NULL) ? sizeof (*ip4) : (2 * sizeof (*ip4) -
401  sizeof (*ip6)));
402  ip4->checksum = ip4_header_checksum (ip4);
403 
404  //Recompute ICMP checksum
405  icmp->checksum = 0;
406  csum =
407  ip_incremental_checksum (0, icmp,
408  clib_net_to_host_u16 (ip4->length) -
409  sizeof (*ip4));
410  icmp->checksum = ~ip_csum_fold (csum);
411 
412  return 0;
413 }
414 
415 /**
416  * @brief Translate IPv6 fragmented packet to IPv4.
417  *
418  * @param p Buffer to translate.
419  * @param fn The function to translate header.
420  * @param ctx A context passed in the header translate function.
421  *
422  * @returns 0 on success, non-zero value otherwise.
423  */
424 always_inline int
426 {
427  ip6_header_t *ip6;
428  ip6_frag_hdr_t *frag;
429  ip4_header_t *ip4;
430  u16 frag_id;
431  u8 frag_more;
432  u16 frag_offset;
433  u8 l4_protocol;
434  u16 l4_offset;
435  int rv;
436 
437  ip6 = vlib_buffer_get_current (p);
438 
439  if (ip6_parse
440  (ip6, p->current_length, &l4_protocol, &l4_offset, &frag_offset))
441  return -1;
442 
443  frag = (ip6_frag_hdr_t *) u8_ptr_add (ip6, frag_offset);
444  ip4 = (ip4_header_t *) u8_ptr_add (ip6, l4_offset - sizeof (*ip4));
445  vlib_buffer_advance (p, l4_offset - sizeof (*ip4));
446 
447  frag_id = frag_id_6to4 (frag->identification);
448  frag_more = ip6_frag_hdr_more (frag);
449  frag_offset = ip6_frag_hdr_offset (frag);
450 
451  if ((rv = fn (ip6, ip4, ctx)) != 0)
452  return rv;
453 
456  ip4->tos = ip6_translate_tos (ip6);
457  ip4->length = u16_net_add (ip6->payload_length,
458  sizeof (*ip4) - l4_offset + sizeof (*ip6));
459  ip4->fragment_id = frag_id;
461  clib_host_to_net_u16 (frag_offset |
462  (frag_more ? IP4_HEADER_FLAG_MORE_FRAGMENTS : 0));
463  ip4->ttl = ip6->hop_limit;
464  ip4->protocol =
465  (l4_protocol == IP_PROTOCOL_ICMP6) ? IP_PROTOCOL_ICMP : l4_protocol;
466  ip4->checksum = ip4_header_checksum (ip4);
467 
468  return 0;
469 }
470 
471 /**
472  * @brief Translate IPv6 UDP/TCP packet to IPv4.
473  *
474  * @param p Buffer to translate.
475  * @param fn The function to translate header.
476  * @param ctx A context passed in the header translate function.
477  *
478  * @returns 0 on success, non-zero value otherwise.
479  */
480 always_inline int
483 {
484  ip6_header_t *ip6;
485  u16 *checksum;
486  ip_csum_t csum = 0;
487  ip4_header_t *ip4;
488  u16 fragment_id;
489  u16 flags;
490  u16 frag_offset;
491  u8 l4_protocol;
492  u16 l4_offset;
493  int rv;
494  ip6_address_t old_src, old_dst;
495 
496  ip6 = vlib_buffer_get_current (p);
497 
498  if (ip6_parse
499  (ip6, p->current_length, &l4_protocol, &l4_offset, &frag_offset))
500  return -1;
501 
502  if (l4_protocol == IP_PROTOCOL_TCP)
503  {
504  tcp_header_t *tcp = ip6_next_header (ip6);
505  checksum = &tcp->checksum;
506  }
507  else
508  {
509  udp_header_t *udp = ip6_next_header (ip6);
510  checksum = &udp->checksum;
511  }
512 
513  old_src.as_u64[0] = ip6->src_address.as_u64[0];
514  old_src.as_u64[1] = ip6->src_address.as_u64[1];
515  old_dst.as_u64[0] = ip6->dst_address.as_u64[0];
516  old_dst.as_u64[1] = ip6->dst_address.as_u64[1];
517 
518  ip4 = (ip4_header_t *) u8_ptr_add (ip6, l4_offset - sizeof (*ip4));
519 
520  vlib_buffer_advance (p, l4_offset - sizeof (*ip4));
521 
522  if (PREDICT_FALSE (frag_offset))
523  {
524  //Only the first fragment
525  ip6_frag_hdr_t *hdr = (ip6_frag_hdr_t *) u8_ptr_add (ip6, frag_offset);
526  fragment_id = frag_id_6to4 (hdr->identification);
527  flags = clib_host_to_net_u16 (IP4_HEADER_FLAG_MORE_FRAGMENTS);
528  }
529  else
530  {
531  fragment_id = 0;
532  flags = 0;
533  }
534 
535  if ((rv = fn (ip6, ip4, ctx)) != 0)
536  return rv;
537 
540  ip4->tos = ip6_translate_tos (ip6);
541  ip4->length = u16_net_add (ip6->payload_length,
542  sizeof (*ip4) + sizeof (*ip6) - l4_offset);
543  ip4->fragment_id = fragment_id;
545  ip4->ttl = ip6->hop_limit;
546  ip4->protocol = l4_protocol;
547  ip4->checksum = ip4_header_checksum (ip4);
548 
549  //UDP checksum is optional over IPv4
550  if (!udp_checksum && l4_protocol == IP_PROTOCOL_UDP)
551  {
552  *checksum = 0;
553  }
554  else
555  {
556  csum = ip_csum_sub_even (*checksum, old_src.as_u64[0]);
557  csum = ip_csum_sub_even (csum, old_src.as_u64[1]);
558  csum = ip_csum_sub_even (csum, old_dst.as_u64[0]);
559  csum = ip_csum_sub_even (csum, old_dst.as_u64[1]);
560  csum = ip_csum_add_even (csum, ip4->dst_address.as_u32);
561  csum = ip_csum_add_even (csum, ip4->src_address.as_u32);
562  *checksum = ip_csum_fold (csum);
563  }
564 
565  return 0;
566 }
567 
568 /**
569  * @brief Translate IPv6 packet to IPv4 (IP header only).
570  *
571  * @param p Buffer to translate.
572  * @param fn The function to translate header.
573  * @param ctx A context passed in the header translate function.
574  *
575  * @returns 0 on success, non-zero value otherwise.
576  */
577 always_inline int
579 {
580  ip6_header_t *ip6;
581  ip4_header_t *ip4;
582  u16 fragment_id;
583  u16 flags;
584  u16 frag_offset;
585  u8 l4_protocol;
586  u16 l4_offset;
587  int rv;
588 
589  ip6 = vlib_buffer_get_current (p);
590 
591  if (ip6_parse
592  (ip6, p->current_length, &l4_protocol, &l4_offset, &frag_offset))
593  return -1;
594 
595  ip4 = (ip4_header_t *) u8_ptr_add (ip6, l4_offset - sizeof (*ip4));
596 
597  vlib_buffer_advance (p, l4_offset - sizeof (*ip4));
598 
599  if (PREDICT_FALSE (frag_offset))
600  {
601  //Only the first fragment
602  ip6_frag_hdr_t *hdr = (ip6_frag_hdr_t *) u8_ptr_add (ip6, frag_offset);
603  fragment_id = frag_id_6to4 (hdr->identification);
604  flags = clib_host_to_net_u16 (IP4_HEADER_FLAG_MORE_FRAGMENTS);
605  }
606  else
607  {
608  fragment_id = 0;
609  flags = 0;
610  }
611 
612  if ((rv = fn (ip6, ip4, ctx)) != 0)
613  return rv;
614 
617  ip4->tos = ip6_translate_tos (ip6);
618  ip4->length = u16_net_add (ip6->payload_length,
619  sizeof (*ip4) + sizeof (*ip6) - l4_offset);
620  ip4->fragment_id = fragment_id;
622  ip4->ttl = ip6->hop_limit;
623  ip4->protocol = l4_protocol;
624  ip4->checksum = ip4_header_checksum (ip4);
625 
626  return 0;
627 }
628 
629 #endif /* __included_ip6_to_ip4_h__ */
630 
631 /*
632  * fd.io coding-style-patch-verification: ON
633  *
634  * Local Variables:
635  * eval: (c-set-style "gnu")
636  * End:
637  */
static_always_inline u8 ip6_translate_tos(const ip6_header_t *ip6)
Translate TOS value from IPv6 to IPv4.
Definition: ip6_to_ip4.h:231
u32 flags
Definition: vhost_user.h:115
static u16 ip6_get_port(ip6_header_t *ip6, u8 sender, u16 buffer_len)
Get TCP/UDP port number or ICMP id from IPv6 packet.
Definition: ip6_to_ip4.h:90
u16 udp_checksum(udp_header_t *uh, u32 udp_len, void *ih, u8 version)
Definition: packets.c:114
ip4_address_t src_address
Definition: ip4_packet.h:170
static int icmp6_to_icmp(vlib_buffer_t *p, ip6_to_ip4_set_fn_t fn, void *ctx, ip6_to_ip4_set_fn_t inner_fn, void *inner_ctx)
Translate ICMP6 packet to ICMP4.
Definition: ip6_to_ip4.h:249
u64 as_u64[2]
Definition: ip6_packet.h:51
#define clib_memcpy_fast(a, b, c)
Definition: string.h:81
#define NULL
Definition: clib.h:58
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:113
uword ip_csum_t
Definition: ip_packet.h:181
u16 flags_and_fragment_offset
Definition: ip4_packet.h:151
struct _tcp_header tcp_header_t
ip6_address_t src_address
Definition: ip6_packet.h:385
unsigned char u8
Definition: types.h:56
u16 src_port
Definition: udp.api:41
static_always_inline int icmp6_to_icmp_header(icmp46_header_t *icmp, ip6_header_t **inner_ip6)
Convert type and code value from ICMP6 to ICMP4.
Definition: ip6_to_ip4.h:136
#define static_always_inline
Definition: clib.h:99
#define always_inline
Definition: clib.h:98
ip4_address_t dst_address
Definition: ip4_packet.h:170
static_always_inline int ip6_parse(const ip6_header_t *ip6, u32 buff_len, u8 *l4_protocol, u16 *l4_offset, u16 *frag_hdr_offset)
Parse some useful information from IPv6 header.
Definition: ip6_to_ip4.h:59
unsigned int u32
Definition: types.h:88
#define frag_id_6to4(id)
Definition: ip6_to_ip4.h:45
static int ip6_to_ip4_tcp_udp(vlib_buffer_t *p, ip6_to_ip4_set_fn_t fn, void *ctx, u8 udp_checksum)
Translate IPv6 UDP/TCP packet to IPv4.
Definition: ip6_to_ip4.h:481
#define ip6_frag_hdr_more(hdr)
Definition: ip6_packet.h:606
long ctx[MAX_CONNS]
Definition: main.c:144
unsigned short u16
Definition: types.h:57
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:229
#define PREDICT_FALSE(x)
Definition: clib.h:111
#define IP4_HEADER_FLAG_MORE_FRAGMENTS
Definition: ip4_packet.h:152
static ip_csum_t ip_incremental_checksum(ip_csum_t sum, void *_data, uword n_bytes)
Definition: ip_packet.h:254
static void * ip6_next_header(ip6_header_t *i)
Definition: ip6_packet.h:412
#define ip6_frag_hdr_offset(hdr)
Definition: ip6_packet.h:600
#define ASSERT(truth)
static ip_csum_t ip_csum_sub_even(ip_csum_t c, ip_csum_t x)
Definition: ip_packet.h:209
static u8 icmp6_to_icmp_updater_pointer_table[]
Definition: ip6_to_ip4.h:31
static void vlib_buffer_advance(vlib_buffer_t *b, word l)
Advance current data pointer by the supplied (signed!) amount.
Definition: buffer.h:248
#define u8_ptr_add(ptr, index)
Definition: ip.h:68
u32 ip_version_traffic_class_and_flow_label
Definition: ip6_packet.h:372
u16 payload_length
Definition: ip6_packet.h:376
VLIB buffer representation.
Definition: buffer.h:102
#define u16_net_add(u, val)
Definition: ip.h:69
#define IP4_VERSION_AND_HEADER_LENGTH_NO_OPTIONS
Definition: ip4_packet.h:194
u8 ip_version_and_header_length
Definition: ip4_packet.h:138
int(* ip6_to_ip4_set_fn_t)(ip6_header_t *ip6, ip4_header_t *ip4, void *ctx)
IPv6 to IPv4 set call back function type.
Definition: ip6_to_ip4.h:27
static int ip6_to_ip4(vlib_buffer_t *p, ip6_to_ip4_set_fn_t fn, void *ctx)
Translate IPv6 packet to IPv4 (IP header only).
Definition: ip6_to_ip4.h:578
static u16 ip4_header_checksum(ip4_header_t *i)
Definition: ip4_packet.h:247
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:237
static ip_csum_t ip_csum_add_even(ip_csum_t c, ip_csum_t x)
Definition: ip_packet.h:192
ip6_address_t dst_address
Definition: ip6_packet.h:385
static int ip6_to_ip4_fragmented(vlib_buffer_t *p, ip6_to_ip4_set_fn_t fn, void *ctx)
Translate IPv6 fragmented packet to IPv4.
Definition: ip6_to_ip4.h:425