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:
7 * http://www.apache.org/licenses/LICENSE-2.0
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.
18 * @brief IPv4 Reassembly.
20 * This file contains the source code for IPv4 reassembly.
23 #include <vppinfra/vec.h>
24 #include <vnet/vnet.h>
25 #include <vnet/ip/ip.h>
26 #include <vppinfra/bihash_16_8.h>
27 #include <vnet/ip/ip4_reassembly.h>
29 #define MSEC_PER_SEC 1000
30 #define IP4_REASS_TIMEOUT_DEFAULT_MS 100
31 #define IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS 10000 // 10 seconds default
32 #define IP4_REASS_MAX_REASSEMBLIES_DEFAULT 1024
33 #define IP4_REASS_HT_LOAD_FACTOR (0.75)
35 #define IP4_REASS_DEBUG_BUFFERS 0
36 #if IP4_REASS_DEBUG_BUFFERS
37 #define IP4_REASS_DEBUG_BUFFER(bi, what) \
41 printf (#what "buffer %u", _bi); \
42 vlib_buffer_t *_b = vlib_get_buffer (vm, _bi); \
43 while (_b->flags & VLIB_BUFFER_NEXT_PRESENT) \
45 _bi = _b->next_buffer; \
46 printf ("[%u]", _bi); \
47 _b = vlib_get_buffer (vm, _bi); \
54 #define IP4_REASS_DEBUG_BUFFER(...)
57 static vlib_node_registration_t ip4_reass_node;
77 ip4_reass_buffer_get_data_offset_no_check (vlib_buffer_t * b)
79 vnet_buffer_opaque_t *vnb = vnet_buffer (b);
80 return vnb->ip.reass.range_first - vnb->ip.reass.fragment_first;
84 ip4_reass_buffer_get_data_offset (vlib_buffer_t * b)
86 vnet_buffer_opaque_t *vnb = vnet_buffer (b);
87 ASSERT (vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first);
88 return ip4_reass_buffer_get_data_offset_no_check (b);
92 ip4_reass_buffer_get_data_len_no_check (vlib_buffer_t * b)
94 vnet_buffer_opaque_t *vnb = vnet_buffer (b);
95 return clib_min (vnb->ip.reass.range_last, vnb->ip.reass.fragment_last) -
96 (vnb->ip.reass.fragment_first + ip4_reass_buffer_get_data_offset (b)) + 1;
100 ip4_reass_buffer_get_data_len (vlib_buffer_t * b)
102 vnet_buffer_opaque_t *vnb = vnet_buffer (b);
103 ASSERT (vnb->ip.reass.range_last > vnb->ip.reass.fragment_first);
104 return ip4_reass_buffer_get_data_len_no_check (b);
111 // time when last packet was received
113 // internal id of this reassembly
115 // buffer index of first buffer in this reassembly context
117 // last octet of packet, ~0 until fragment without more_fragments arrives
118 u32 last_packet_octet;
119 // length of data collected so far
121 // trace operation counter
122 u32 trace_op_counter;
123 // next index - used by non-feature node
125 // minimum fragment length for this reassembly - used to estimate MTU
126 u16 min_fragment_length;
135 clib_spinlock_t lock;
136 } ip4_reass_per_thread_t;
143 u32 expire_walk_interval_ms;
147 clib_bihash_16_8_t hash;
149 ip4_reass_per_thread_t *per_thread_data;
152 vlib_main_t *vlib_main;
153 vnet_main_t *vnet_main;
155 // node index of ip4-drop node
157 u32 ip4_reass_expire_node_idx;
160 ip4_reass_main_t ip4_reass_main;
164 IP4_REASSEMBLY_NEXT_INPUT,
165 IP4_REASSEMBLY_NEXT_DROP,
166 IP4_REASSEMBLY_N_NEXT,
176 } ip4_reass_trace_operation_e;
186 } ip4_reass_range_trace_t;
190 ip4_reass_trace_operation_e action;
192 ip4_reass_range_trace_t trace_range;
201 ip4_reass_trace_details (vlib_main_t * vm, u32 bi,
202 ip4_reass_range_trace_t * trace)
204 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
205 vnet_buffer_opaque_t *vnb = vnet_buffer (b);
206 trace->range_first = vnb->ip.reass.range_first;
207 trace->range_last = vnb->ip.reass.range_last;
208 trace->data_offset = ip4_reass_buffer_get_data_offset_no_check (b);
209 trace->data_len = ip4_reass_buffer_get_data_len_no_check (b);
210 trace->range_bi = bi;
214 format_ip4_reass_range_trace (u8 * s, va_list * args)
216 ip4_reass_range_trace_t *trace = va_arg (*args, ip4_reass_range_trace_t *);
217 s = format (s, "range: [%u, %u], off %d, len %u, bi %u", trace->range_first,
218 trace->range_last, trace->data_offset, trace->data_len,
224 format_ip4_reass_trace (u8 * s, va_list * args)
226 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
227 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
228 ip4_reass_trace_t *t = va_arg (*args, ip4_reass_trace_t *);
229 s = format (s, "reass id: %u, op id: %u ", t->reass_id, t->op_id);
230 u32 indent = format_get_indent (s);
231 s = format (s, "first bi: %u, data len: %u, ip/fragment[%u, %u]",
232 t->trace_range.first_bi, t->total_data_len, t->fragment_first,
237 s = format (s, "\n%Ushrink %U by %u", format_white_space, indent,
238 format_ip4_reass_range_trace, &t->trace_range,
242 s = format (s, "\n%Udiscard %U", format_white_space, indent,
243 format_ip4_reass_range_trace, &t->trace_range);
246 s = format (s, "\n%Unew %U", format_white_space, indent,
247 format_ip4_reass_range_trace, &t->trace_range);
250 s = format (s, "\n%Uoverlapping/ignored %U", format_white_space, indent,
251 format_ip4_reass_range_trace, &t->trace_range);
254 s = format (s, "\n%Ufinalize reassembly", format_white_space, indent);
261 ip4_reass_add_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
262 ip4_reass_main_t * rm, ip4_reass_t * reass, u32 bi,
263 ip4_reass_trace_operation_e action, u32 size_diff)
265 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
266 vnet_buffer_opaque_t *vnb = vnet_buffer (b);
267 if (pool_is_free_index (vm->trace_main.trace_buffer_pool, b->trace_index))
269 // this buffer's trace is gone
270 b->flags &= ~VLIB_BUFFER_IS_TRACED;
273 ip4_reass_trace_t *t = vlib_add_trace (vm, node, b, sizeof (t[0]));
274 t->reass_id = reass->id;
276 ip4_reass_trace_details (vm, bi, &t->trace_range);
277 t->size_diff = size_diff;
278 t->op_id = reass->trace_op_counter;
279 ++reass->trace_op_counter;
280 t->fragment_first = vnb->ip.reass.fragment_first;
281 t->fragment_last = vnb->ip.reass.fragment_last;
282 t->trace_range.first_bi = reass->first_bi;
283 t->total_data_len = reass->data_len;
286 s = format (s, "%U", format_ip4_reass_trace, NULL, NULL, t);
287 printf ("%.*s\n", vec_len (s), s);
289 vec_reset_length (s);
294 ip4_reass_free (ip4_reass_main_t * rm, ip4_reass_per_thread_t * rt,
297 clib_bihash_kv_16_8_t kv;
298 kv.key[0] = reass->key.as_u64[0];
299 kv.key[1] = reass->key.as_u64[1];
300 clib_bihash_add_del_16_8 (&rm->hash, &kv, 0);
301 pool_put (rt->pool, reass);
306 ip4_reass_on_timeout (vlib_main_t * vm, ip4_reass_main_t * rm,
307 ip4_reass_t * reass, u32 ** vec_drop_timeout)
309 u32 range_bi = reass->first_bi;
310 vlib_buffer_t *range_b;
311 vnet_buffer_opaque_t *range_vnb;
312 while (~0 != range_bi)
314 range_b = vlib_get_buffer (vm, range_bi);
315 range_vnb = vnet_buffer (range_b);
319 vec_add1 (*vec_drop_timeout, bi);
320 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
321 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
324 b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
331 range_bi = range_vnb->ip.reass.next_range_bi;
336 ip4_reass_find_or_create (vlib_main_t * vm, ip4_reass_main_t * rm,
337 ip4_reass_per_thread_t * rt,
338 ip4_reass_key_t * k, u32 ** vec_drop_timeout)
340 ip4_reass_t *reass = NULL;
341 f64 now = vlib_time_now (rm->vlib_main);
342 clib_bihash_kv_16_8_t kv, value;
343 kv.key[0] = k->as_u64[0];
344 kv.key[1] = k->as_u64[1];
346 if (!clib_bihash_search_16_8 (&rm->hash, &kv, &value))
348 reass = pool_elt_at_index (rt->pool, value.value);
349 if (now > reass->last_heard + rm->timeout)
351 ip4_reass_on_timeout (vm, rm, reass, vec_drop_timeout);
352 ip4_reass_free (rm, rt, reass);
359 reass->last_heard = now;
363 if (rt->reass_n >= rm->max_reass_n)
370 pool_get (rt->pool, reass);
371 clib_memset (reass, 0, sizeof (*reass));
373 ((u64) os_get_thread_index () * 1000000000) + rt->id_counter;
375 reass->first_bi = ~0;
376 reass->last_packet_octet = ~0;
381 reass->key.as_u64[0] = kv.key[0] = k->as_u64[0];
382 reass->key.as_u64[1] = kv.key[1] = k->as_u64[1];
383 kv.value = reass - rt->pool;
384 reass->last_heard = now;
386 if (clib_bihash_add_del_16_8 (&rm->hash, &kv, 1))
388 ip4_reass_free (rm, rt, reass);
396 ip4_reass_finalize (vlib_main_t * vm, vlib_node_runtime_t * node,
397 ip4_reass_main_t * rm, ip4_reass_per_thread_t * rt,
398 ip4_reass_t * reass, u32 * bi0, u32 * next0,
399 u32 * error0, u32 ** vec_drop_compress,
400 u32 ** vec_drop_overlap, bool is_feature)
402 ASSERT (~0 != reass->first_bi);
403 vlib_buffer_t *first_b = vlib_get_buffer (vm, reass->first_bi);
404 vlib_buffer_t *last_b = NULL;
405 u32 sub_chain_bi = reass->first_bi;
406 u32 total_length = 0;
411 u32 tmp_bi = sub_chain_bi;
412 vlib_buffer_t *tmp = vlib_get_buffer (vm, tmp_bi);
413 ip4_header_t *ip = vlib_buffer_get_current (tmp);
414 u32 data_len = ip4_reass_buffer_get_data_len (tmp);
416 ip4_header_bytes (ip) + ip4_reass_buffer_get_data_offset (tmp);
418 vlib_buffer_length_in_chain (vm, tmp) - trim_front - data_len;
419 if (tmp_bi == reass->first_bi)
421 /* first buffer - keep ip4 header */
422 ASSERT (0 == ip4_reass_buffer_get_data_offset (tmp));
424 trim_end = vlib_buffer_length_in_chain (vm, tmp) - data_len -
425 ip4_header_bytes (ip);
426 ASSERT (vlib_buffer_length_in_chain (vm, tmp) - trim_end > 0);
429 vlib_buffer_length_in_chain (vm, tmp) - trim_front - trim_end;
435 if (trim_front > tmp->current_length)
437 /* drop whole buffer */
438 vec_add1 (*vec_drop_compress, tmp_bi);
440 trim_front -= tmp->current_length;
441 ASSERT (tmp->flags & VLIB_BUFFER_NEXT_PRESENT);
442 tmp->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
443 tmp_bi = tmp->next_buffer;
444 tmp = vlib_get_buffer (vm, tmp_bi);
449 vlib_buffer_advance (tmp, trim_front);
457 last_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
458 last_b->next_buffer = tmp_bi;
461 if (keep_data <= tmp->current_length)
463 tmp->current_length = keep_data;
468 keep_data -= tmp->current_length;
469 ASSERT (tmp->flags & VLIB_BUFFER_NEXT_PRESENT);
471 total_length += tmp->current_length;
475 vec_add1 (*vec_drop_overlap, tmp_bi);
476 ASSERT (reass->first_bi != tmp_bi);
479 if (tmp->flags & VLIB_BUFFER_NEXT_PRESENT)
481 tmp_bi = tmp->next_buffer;
482 tmp = vlib_get_buffer (vm, tmp->next_buffer);
490 vnet_buffer (vlib_get_buffer (vm, sub_chain_bi))->ip.
493 while (~0 != sub_chain_bi);
495 ASSERT (last_b != NULL);
496 last_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
497 ASSERT (rt->buffers_n >= (buf_cnt - dropped_cnt));
498 rt->buffers_n -= buf_cnt - dropped_cnt;
499 ASSERT (total_length >= first_b->current_length);
500 total_length -= first_b->current_length;
501 first_b->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
502 first_b->total_length_not_including_first_buffer = total_length;
503 ip4_header_t *ip = vlib_buffer_get_current (first_b);
504 ip->flags_and_fragment_offset = 0;
505 ip->length = clib_host_to_net_u16 (first_b->current_length + total_length);
506 ip->checksum = ip4_header_checksum (ip);
507 u32 before = vec_len (*vec_drop_compress);
508 vlib_buffer_chain_compress (vm, first_b, vec_drop_compress);
509 rt->buffers_n += vec_len (*vec_drop_compress) - before;
511 if (PREDICT_FALSE (first_b->flags & VLIB_BUFFER_IS_TRACED))
513 ip4_reass_add_trace (vm, node, rm, reass, reass->first_bi, FINALIZE, 0);
515 // following code does a hexdump of packet fragments to stdout ...
518 u32 bi = reass->first_bi;
522 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
523 s = format (s, "%u: %U\n", bi, format_hexdump,
524 vlib_buffer_get_current (b), b->current_length);
525 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
534 printf ("%.*s\n", vec_len (s), s);
541 *bi0 = reass->first_bi;
544 *next0 = IP4_REASSEMBLY_NEXT_INPUT;
548 *next0 = reass->next_index;
550 vnet_buffer (first_b)->ip.reass.estimated_mtu = reass->min_fragment_length;
551 *error0 = IP4_ERROR_NONE;
552 ip4_reass_free (rm, rt, reass);
557 ip4_reass_get_buffer_chain_length (vlib_main_t * vm, vlib_buffer_t * b)
563 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
565 b = vlib_get_buffer (vm, b->next_buffer);
576 ip4_reass_insert_range_in_chain (vlib_main_t * vm,
577 ip4_reass_main_t * rm,
578 ip4_reass_per_thread_t * rt,
580 u32 prev_range_bi, u32 new_next_bi)
583 vlib_buffer_t *new_next_b = vlib_get_buffer (vm, new_next_bi);
584 vnet_buffer_opaque_t *new_next_vnb = vnet_buffer (new_next_b);
585 if (~0 != prev_range_bi)
587 vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
588 vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
589 new_next_vnb->ip.reass.next_range_bi = prev_vnb->ip.reass.next_range_bi;
590 prev_vnb->ip.reass.next_range_bi = new_next_bi;
594 if (~0 != reass->first_bi)
596 new_next_vnb->ip.reass.next_range_bi = reass->first_bi;
598 reass->first_bi = new_next_bi;
600 reass->data_len += ip4_reass_buffer_get_data_len (new_next_b);
601 rt->buffers_n += ip4_reass_get_buffer_chain_length (vm, new_next_b);
605 ip4_reass_remove_range_from_chain (vlib_main_t * vm,
606 vlib_node_runtime_t * node,
607 ip4_reass_main_t * rm,
608 u32 ** vec_drop_overlap,
609 ip4_reass_t * reass, u32 prev_range_bi,
612 vlib_buffer_t *discard_b = vlib_get_buffer (vm, discard_bi);
613 vnet_buffer_opaque_t *discard_vnb = vnet_buffer (discard_b);
614 if (~0 != prev_range_bi)
616 vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
617 vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
618 ASSERT (prev_vnb->ip.reass.next_range_bi == discard_bi);
619 prev_vnb->ip.reass.next_range_bi = discard_vnb->ip.reass.next_range_bi;
623 reass->first_bi = discard_vnb->ip.reass.next_range_bi;
625 reass->data_len -= ip4_reass_buffer_get_data_len (discard_b);
628 vec_add1 (*vec_drop_overlap, discard_bi);
629 if (PREDICT_FALSE (discard_b->flags & VLIB_BUFFER_IS_TRACED))
631 ip4_reass_add_trace (vm, node, rm, reass, discard_bi, RANGE_DISCARD,
634 if (discard_b->flags & VLIB_BUFFER_NEXT_PRESENT)
636 discard_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
637 discard_bi = discard_b->next_buffer;
638 discard_b = vlib_get_buffer (vm, discard_bi);
648 ip4_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
649 ip4_reass_main_t * rm, ip4_reass_per_thread_t * rt,
650 ip4_reass_t * reass, u32 * bi0, u32 * next0,
651 u32 * error0, u32 ** vec_drop_overlap,
652 u32 ** vec_drop_compress, bool is_feature)
655 vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
656 ip4_header_t *fip = vlib_buffer_get_current (fb);
657 ASSERT (fb->current_length >= sizeof (*fip));
658 vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
659 reass->next_index = fvnb->ip.reass.next_index; // store next_index before it's overwritten
660 const u32 fragment_first = ip4_get_fragment_offset_bytes (fip);
661 const u32 fragment_length =
662 clib_net_to_host_u16 (fip->length) - ip4_header_bytes (fip);
663 const u32 fragment_last = fragment_first + fragment_length - 1;
664 fvnb->ip.reass.fragment_first = fragment_first;
665 fvnb->ip.reass.fragment_last = fragment_last;
666 int more_fragments = ip4_get_fragment_more (fip);
667 u32 candidate_range_bi = reass->first_bi;
668 u32 prev_range_bi = ~0;
669 fvnb->ip.reass.range_first = fragment_first;
670 fvnb->ip.reass.range_last = fragment_last;
671 fvnb->ip.reass.next_range_bi = ~0;
674 reass->last_packet_octet = fragment_last;
676 if (~0 == reass->first_bi)
678 // starting a new reassembly
679 ip4_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
681 if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
683 ip4_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
686 reass->min_fragment_length = clib_net_to_host_u16 (fip->length);
689 reass->min_fragment_length = clib_min (clib_net_to_host_u16 (fip->length),
690 fvnb->ip.reass.estimated_mtu);
691 while (~0 != candidate_range_bi)
693 vlib_buffer_t *candidate_b = vlib_get_buffer (vm, candidate_range_bi);
694 vnet_buffer_opaque_t *candidate_vnb = vnet_buffer (candidate_b);
695 if (fragment_first > candidate_vnb->ip.reass.range_last)
697 // this fragments starts after candidate range
698 prev_range_bi = candidate_range_bi;
699 candidate_range_bi = candidate_vnb->ip.reass.next_range_bi;
700 if (candidate_vnb->ip.reass.range_last < fragment_last &&
701 ~0 == candidate_range_bi)
703 // special case - this fragment falls beyond all known ranges
704 ip4_reass_insert_range_in_chain (vm, rm, rt, reass,
705 prev_range_bi, *bi0);
711 if (fragment_last < candidate_vnb->ip.reass.range_first)
713 // this fragment ends before candidate range without any overlap
714 ip4_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
720 if (fragment_first >= candidate_vnb->ip.reass.range_first &&
721 fragment_last <= candidate_vnb->ip.reass.range_last)
723 // this fragment is a (sub)part of existing range, ignore it
724 if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
726 ip4_reass_add_trace (vm, node, rm, reass, *bi0,
731 int discard_candidate = 0;
732 if (fragment_first < candidate_vnb->ip.reass.range_first)
735 fragment_last - candidate_vnb->ip.reass.range_first + 1;
736 if (overlap < ip4_reass_buffer_get_data_len (candidate_b))
738 candidate_vnb->ip.reass.range_first += overlap;
739 ASSERT (reass->data_len >= overlap);
740 reass->data_len -= overlap;
741 if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
743 ip4_reass_add_trace (vm, node, rm, reass,
744 candidate_range_bi, RANGE_SHRINK,
747 ip4_reass_insert_range_in_chain (vm, rm, rt, reass,
748 prev_range_bi, *bi0);
753 discard_candidate = 1;
756 else if (fragment_last > candidate_vnb->ip.reass.range_last)
759 candidate_vnb->ip.reass.range_last - fragment_first + 1;
760 if (overlap < ip4_reass_buffer_get_data_len (candidate_b))
762 fvnb->ip.reass.range_first += overlap;
763 if (~0 != candidate_vnb->ip.reass.next_range_bi)
765 prev_range_bi = candidate_range_bi;
767 candidate_vnb->ip.reass.next_range_bi;
772 // special case - last range discarded
773 ip4_reass_insert_range_in_chain (vm, rm, rt, reass,
781 discard_candidate = 1;
786 discard_candidate = 1;
788 if (discard_candidate)
790 u32 next_range_bi = candidate_vnb->ip.reass.next_range_bi;
791 // discard candidate range, probe next range
792 ip4_reass_remove_range_from_chain (vm, node, rm,
793 vec_drop_overlap, reass,
796 if (~0 != next_range_bi)
798 candidate_range_bi = next_range_bi;
803 // special case - last range discarded
804 ip4_reass_insert_range_in_chain (vm, rm, rt, reass,
805 prev_range_bi, *bi0);
814 if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
816 ip4_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
819 if (~0 != reass->last_packet_octet &&
820 reass->data_len == reass->last_packet_octet + 1)
822 ip4_reass_finalize (vm, node, rm, rt, reass, bi0, next0, error0,
823 vec_drop_compress, vec_drop_overlap, is_feature);
833 *next0 = IP4_REASSEMBLY_NEXT_DROP;
834 *error0 = IP4_ERROR_REASS_DUPLICATE_FRAGMENT;
840 ip4_reassembly_inline (vlib_main_t * vm,
841 vlib_node_runtime_t * node,
842 vlib_frame_t * frame, bool is_feature)
844 u32 *from = vlib_frame_vector_args (frame);
845 u32 n_left_from, n_left_to_next, *to_next, next_index;
846 ip4_reass_main_t *rm = &ip4_reass_main;
847 ip4_reass_per_thread_t *rt = &rm->per_thread_data[os_get_thread_index ()];
848 clib_spinlock_lock (&rt->lock);
850 n_left_from = frame->n_vectors;
851 next_index = node->cached_next_index;
852 static u32 *vec_drop_timeout = NULL; // indexes of buffers which timed out
853 static u32 *vec_drop_overlap = NULL; // indexes of buffers which were discarded due to overlap
854 static u32 *vec_drop_compress = NULL; // indexes of buffers dicarded due to buffer compression
855 while (n_left_from > 0 || vec_len (vec_drop_timeout) > 0 ||
856 vec_len (vec_drop_overlap) > 0 || vec_len (vec_drop_compress) > 0)
858 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
860 while (vec_len (vec_drop_timeout) > 0 && n_left_to_next > 0)
862 u32 bi = vec_pop (vec_drop_timeout);
863 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
864 b->error = node->errors[IP4_ERROR_REASS_TIMEOUT];
868 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
870 IP4_REASSEMBLY_NEXT_DROP);
871 IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_timeout);
872 ASSERT (rt->buffers_n > 0);
876 while (vec_len (vec_drop_overlap) > 0 && n_left_to_next > 0)
878 u32 bi = vec_pop (vec_drop_overlap);
879 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
880 b->error = node->errors[IP4_ERROR_REASS_DUPLICATE_FRAGMENT];
884 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
886 IP4_REASSEMBLY_NEXT_DROP);
887 IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_duplicate_fragment);
888 ASSERT (rt->buffers_n > 0);
892 while (vec_len (vec_drop_compress) > 0 && n_left_to_next > 0)
894 u32 bi = vec_pop (vec_drop_compress);
895 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
896 b->error = node->errors[IP4_ERROR_NONE];
900 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
902 IP4_REASSEMBLY_NEXT_DROP);
903 IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_compress);
904 ASSERT (rt->buffers_n > 0);
908 while (n_left_from > 0 && n_left_to_next > 0)
913 u32 error0 = IP4_ERROR_NONE;
916 b0 = vlib_get_buffer (vm, bi0);
918 ip4_header_t *ip0 = vlib_buffer_get_current (b0);
919 if (!ip4_get_fragment_more (ip0) && !ip4_get_fragment_offset (ip0))
921 // this is a whole packet - no fragmentation
924 next0 = IP4_REASSEMBLY_NEXT_INPUT;
928 next0 = vnet_buffer (b0)->ip.reass.next_index;
933 ip4_header_t *fip = vlib_buffer_get_current (b0);
934 const u32 fragment_first = ip4_get_fragment_offset_bytes (fip);
935 const u32 fragment_length =
936 clib_net_to_host_u16 (fip->length) - ip4_header_bytes (fip);
937 const u32 fragment_last = fragment_first + fragment_length - 1;
938 if (fragment_first > fragment_last
939 || fragment_first + fragment_length > UINT16_MAX - 20)
941 next0 = IP4_REASSEMBLY_NEXT_DROP;
942 error0 = IP4_ERROR_REASS_MALFORMED_PACKET;
948 (u64) vnet_buffer (b0)->sw_if_index[VLIB_RX] << 32 | (u64)
949 ip0->src_address.as_u32;
951 (u64) ip0->dst_address.
952 as_u32 << 32 | (u64) ip0->fragment_id << 16 | (u64) ip0->
956 ip4_reass_find_or_create (vm, rm, rt, &k,
961 ip4_reass_update (vm, node, rm, rt, reass, &bi0, &next0,
962 &error0, &vec_drop_overlap,
963 &vec_drop_compress, is_feature);
967 next0 = IP4_REASSEMBLY_NEXT_DROP;
968 error0 = IP4_ERROR_REASS_LIMIT_REACHED;
972 b0->error = node->errors[error0];
980 if (is_feature && IP4_ERROR_NONE == error0)
982 b0 = vlib_get_buffer (vm, bi0);
983 vnet_feature_next (&next0, b0);
985 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
986 n_left_to_next, bi0, next0);
987 IP4_REASS_DEBUG_BUFFER (bi0, enqueue_next);
994 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
997 clib_spinlock_unlock (&rt->lock);
998 return frame->n_vectors;
1001 static char *ip4_reassembly_error_strings[] = {
1002 #define _(sym, string) string,
1008 ip4_reassembly (vlib_main_t * vm, vlib_node_runtime_t * node,
1009 vlib_frame_t * frame)
1011 return ip4_reassembly_inline (vm, node, frame, false /* is_feature */ );
1015 VLIB_REGISTER_NODE (ip4_reass_node, static) = {
1016 .function = ip4_reassembly,
1017 .name = "ip4-reassembly",
1018 .vector_size = sizeof (u32),
1019 .format_trace = format_ip4_reass_trace,
1020 .n_errors = ARRAY_LEN (ip4_reassembly_error_strings),
1021 .error_strings = ip4_reassembly_error_strings,
1022 .n_next_nodes = IP4_REASSEMBLY_N_NEXT,
1025 [IP4_REASSEMBLY_NEXT_INPUT] = "ip4-input",
1026 [IP4_REASSEMBLY_NEXT_DROP] = "ip4-drop",
1031 VLIB_NODE_FUNCTION_MULTIARCH (ip4_reass_node, ip4_reassembly);
1034 ip4_reassembly_feature (vlib_main_t * vm,
1035 vlib_node_runtime_t * node, vlib_frame_t * frame)
1037 return ip4_reassembly_inline (vm, node, frame, true /* is_feature */ );
1041 VLIB_REGISTER_NODE (ip4_reass_node_feature, static) = {
1042 .function = ip4_reassembly_feature,
1043 .name = "ip4-reassembly-feature",
1044 .vector_size = sizeof (u32),
1045 .format_trace = format_ip4_reass_trace,
1046 .n_errors = ARRAY_LEN (ip4_reassembly_error_strings),
1047 .error_strings = ip4_reassembly_error_strings,
1048 .n_next_nodes = IP4_REASSEMBLY_N_NEXT,
1051 [IP4_REASSEMBLY_NEXT_INPUT] = "ip4-input",
1052 [IP4_REASSEMBLY_NEXT_DROP] = "ip4-drop",
1057 VLIB_NODE_FUNCTION_MULTIARCH (ip4_reass_node_feature, ip4_reassembly_feature);
1060 VNET_FEATURE_INIT (ip4_reassembly_feature, static) = {
1061 .arc_name = "ip4-unicast",
1062 .node_name = "ip4-reassembly-feature",
1063 .runs_before = VNET_FEATURES ("ip4-lookup"),
1069 ip4_reass_get_nbuckets ()
1071 ip4_reass_main_t *rm = &ip4_reass_main;
1075 nbuckets = (u32) (rm->max_reass_n / IP4_REASS_HT_LOAD_FACTOR);
1077 for (i = 0; i < 31; i++)
1078 if ((1 << i) >= nbuckets)
1087 IP4_EVENT_CONFIG_CHANGED = 1,
1088 } ip4_reass_event_t;
1093 clib_bihash_16_8_t *new_hash;
1094 } ip4_rehash_cb_ctx;
1097 ip4_rehash_cb (clib_bihash_kv_16_8_t * kv, void *_ctx)
1099 ip4_rehash_cb_ctx *ctx = _ctx;
1100 if (clib_bihash_add_del_16_8 (ctx->new_hash, kv, 1))
1107 ip4_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1108 u32 expire_walk_interval_ms)
1110 ip4_reass_main.timeout_ms = timeout_ms;
1111 ip4_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1112 ip4_reass_main.max_reass_n = max_reassemblies;
1113 ip4_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1117 ip4_reass_set (u32 timeout_ms, u32 max_reassemblies,
1118 u32 expire_walk_interval_ms)
1120 u32 old_nbuckets = ip4_reass_get_nbuckets ();
1121 ip4_reass_set_params (timeout_ms, max_reassemblies,
1122 expire_walk_interval_ms);
1123 vlib_process_signal_event (ip4_reass_main.vlib_main,
1124 ip4_reass_main.ip4_reass_expire_node_idx,
1125 IP4_EVENT_CONFIG_CHANGED, 0);
1126 u32 new_nbuckets = ip4_reass_get_nbuckets ();
1127 if (ip4_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1129 clib_bihash_16_8_t new_hash;
1130 clib_memset (&new_hash, 0, sizeof (new_hash));
1131 ip4_rehash_cb_ctx ctx;
1133 ctx.new_hash = &new_hash;
1134 clib_bihash_init_16_8 (&new_hash, "ip4-reass", new_nbuckets,
1135 new_nbuckets * 1024);
1136 clib_bihash_foreach_key_value_pair_16_8 (&ip4_reass_main.hash,
1137 ip4_rehash_cb, &ctx);
1140 clib_bihash_free_16_8 (&new_hash);
1145 clib_bihash_free_16_8 (&ip4_reass_main.hash);
1146 clib_memcpy_fast (&ip4_reass_main.hash, &new_hash,
1147 sizeof (ip4_reass_main.hash));
1154 ip4_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1155 u32 * expire_walk_interval_ms)
1157 *timeout_ms = ip4_reass_main.timeout_ms;
1158 *max_reassemblies = ip4_reass_main.max_reass_n;
1159 *expire_walk_interval_ms = ip4_reass_main.expire_walk_interval_ms;
1163 static clib_error_t *
1164 ip4_reass_init_function (vlib_main_t * vm)
1166 ip4_reass_main_t *rm = &ip4_reass_main;
1167 clib_error_t *error = 0;
1172 rm->vnet_main = vnet_get_main ();
1174 vec_validate (rm->per_thread_data, vlib_num_workers ());
1175 ip4_reass_per_thread_t *rt;
1176 vec_foreach (rt, rm->per_thread_data)
1178 clib_spinlock_init (&rt->lock);
1179 pool_alloc (rt->pool, rm->max_reass_n);
1182 node = vlib_get_node_by_name (vm, (u8 *) "ip4-reassembly-expire-walk");
1184 rm->ip4_reass_expire_node_idx = node->index;
1186 ip4_reass_set_params (IP4_REASS_TIMEOUT_DEFAULT_MS,
1187 IP4_REASS_MAX_REASSEMBLIES_DEFAULT,
1188 IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1190 nbuckets = ip4_reass_get_nbuckets ();
1191 clib_bihash_init_16_8 (&rm->hash, "ip4-reass", nbuckets, nbuckets * 1024);
1193 node = vlib_get_node_by_name (vm, (u8 *) "ip4-drop");
1195 rm->ip4_drop_idx = node->index;
1200 VLIB_INIT_FUNCTION (ip4_reass_init_function);
1203 ip4_reass_walk_expired (vlib_main_t * vm,
1204 vlib_node_runtime_t * node, vlib_frame_t * f)
1206 ip4_reass_main_t *rm = &ip4_reass_main;
1207 uword event_type, *event_data = 0;
1211 vlib_process_wait_for_event_or_clock (vm,
1212 (f64) rm->expire_walk_interval_ms
1213 / (f64) MSEC_PER_SEC);
1214 event_type = vlib_process_get_events (vm, &event_data);
1218 case ~0: /* no events => timeout */
1219 /* nothing to do here */
1221 case IP4_EVENT_CONFIG_CHANGED:
1224 clib_warning ("BUG: event type 0x%wx", event_type);
1227 f64 now = vlib_time_now (vm);
1230 u32 *vec_drop_timeout = NULL;
1231 int *pool_indexes_to_free = NULL;
1233 uword thread_index = 0;
1235 const uword nthreads = vlib_num_workers () + 1;
1236 for (thread_index = 0; thread_index < nthreads; ++thread_index)
1238 ip4_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1239 clib_spinlock_lock (&rt->lock);
1241 vec_reset_length (pool_indexes_to_free);
1243 pool_foreach_index (index, rt->pool, ({
1244 reass = pool_elt_at_index (rt->pool, index);
1245 if (now > reass->last_heard + rm->timeout)
1247 vec_add1 (pool_indexes_to_free, index);
1253 vec_foreach (i, pool_indexes_to_free)
1255 ip4_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1256 u32 before = vec_len (vec_drop_timeout);
1257 vlib_buffer_t *b = vlib_get_buffer (vm, reass->first_bi);
1258 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1260 if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1263 /* the trace is gone, don't trace this buffer anymore */
1264 b->flags &= ~VLIB_BUFFER_IS_TRACED;
1267 ip4_reass_on_timeout (vm, rm, reass, &vec_drop_timeout);
1268 u32 after = vec_len (vec_drop_timeout);
1269 ASSERT (rt->buffers_n >= (after - before));
1270 rt->buffers_n -= (after - before);
1271 ip4_reass_free (rm, rt, reass);
1275 clib_spinlock_unlock (&rt->lock);
1278 while (vec_len (vec_drop_timeout) > 0)
1280 vlib_frame_t *f = vlib_get_frame_to_node (vm, rm->ip4_drop_idx);
1281 u32 *to_next = vlib_frame_vector_args (f);
1282 u32 n_left_to_next = VLIB_FRAME_SIZE - f->n_vectors;
1283 int trace_frame = 0;
1284 while (vec_len (vec_drop_timeout) > 0 && n_left_to_next > 0)
1286 u32 bi = vec_pop (vec_drop_timeout);
1287 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1288 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1290 if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1293 /* the trace is gone, don't trace this buffer anymore */
1294 b->flags &= ~VLIB_BUFFER_IS_TRACED;
1301 b->error = node->errors[IP4_ERROR_REASS_TIMEOUT];
1305 n_left_to_next -= 1;
1306 IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_timeout_walk);
1308 f->frame_flags |= (trace_frame * VLIB_FRAME_TRACE);
1309 vlib_put_frame_to_node (vm, rm->ip4_drop_idx, f);
1312 vec_free (pool_indexes_to_free);
1313 vec_free (vec_drop_timeout);
1316 _vec_len (event_data) = 0;
1323 static vlib_node_registration_t ip4_reass_expire_node;
1326 VLIB_REGISTER_NODE (ip4_reass_expire_node, static) = {
1327 .function = ip4_reass_walk_expired,
1328 .type = VLIB_NODE_TYPE_PROCESS,
1329 .name = "ip4-reassembly-expire-walk",
1330 .format_trace = format_ip4_reass_trace,
1331 .n_errors = ARRAY_LEN (ip4_reassembly_error_strings),
1332 .error_strings = ip4_reassembly_error_strings,
1338 format_ip4_reass_key (u8 * s, va_list * args)
1340 ip4_reass_key_t *key = va_arg (*args, ip4_reass_key_t *);
1341 s = format (s, "xx_id: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1342 key->xx_id, format_ip4_address, &key->src, format_ip4_address,
1343 &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1348 format_ip4_reass (u8 * s, va_list * args)
1350 vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1351 ip4_reass_t *reass = va_arg (*args, ip4_reass_t *);
1353 s = format (s, "ID: %lu, key: %U\n first_bi: %u, data_len: %u, "
1354 "last_packet_octet: %u, trace_op_counter: %u\n",
1355 reass->id, format_ip4_reass_key, &reass->key, reass->first_bi,
1356 reass->data_len, reass->last_packet_octet,
1357 reass->trace_op_counter);
1358 u32 bi = reass->first_bi;
1362 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1363 vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1364 s = format (s, " #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1365 "fragment[%u, %u]\n",
1366 counter, vnb->ip.reass.range_first,
1367 vnb->ip.reass.range_last, bi,
1368 ip4_reass_buffer_get_data_offset_no_check (b),
1369 ip4_reass_buffer_get_data_len_no_check (b),
1370 vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1371 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1373 bi = b->next_buffer;
1383 static clib_error_t *
1384 show_ip4_reass (vlib_main_t * vm, unformat_input_t * input,
1385 CLIB_UNUSED (vlib_cli_command_t * lmd))
1387 ip4_reass_main_t *rm = &ip4_reass_main;
1389 vlib_cli_output (vm, "---------------------");
1390 vlib_cli_output (vm, "IP4 reassembly status");
1391 vlib_cli_output (vm, "---------------------");
1392 bool details = false;
1393 if (unformat (input, "details"))
1398 u32 sum_reass_n = 0;
1399 u64 sum_buffers_n = 0;
1402 const uword nthreads = vlib_num_workers () + 1;
1403 for (thread_index = 0; thread_index < nthreads; ++thread_index)
1405 ip4_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1406 clib_spinlock_lock (&rt->lock);
1410 pool_foreach (reass, rt->pool, {
1411 vlib_cli_output (vm, "%U", format_ip4_reass, vm, reass);
1415 sum_reass_n += rt->reass_n;
1416 sum_buffers_n += rt->buffers_n;
1417 clib_spinlock_unlock (&rt->lock);
1419 vlib_cli_output (vm, "---------------------");
1420 vlib_cli_output (vm, "Current IP4 reassemblies count: %lu\n",
1421 (long unsigned) sum_reass_n);
1422 vlib_cli_output (vm,
1423 "Maximum configured concurrent IP4 reassemblies per worker-thread: %lu\n",
1424 (long unsigned) rm->max_reass_n);
1425 vlib_cli_output (vm, "Buffers in use: %lu\n",
1426 (long unsigned) sum_buffers_n);
1431 VLIB_CLI_COMMAND (show_ip4_reassembly_cmd, static) = {
1432 .path = "show ip4-reassembly",
1433 .short_help = "show ip4-reassembly [details]",
1434 .function = show_ip4_reass,
1439 ip4_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1441 return vnet_feature_enable_disable ("ip4-unicast", "ip4-reassembly-feature",
1442 sw_if_index, enable_disable, 0, 0);
1446 * fd.io coding-style-patch-verification: ON
1449 * eval: (c-set-style "gnu")