ip: reassembly: send packet out on correct worker
[vpp.git] / src / vnet / ip / ip6_reassembly.c
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 /**
17  * @file
18  * @brief IPv6 Reassembly.
19  *
20  * This file contains the source code for IPv6 reassembly.
21  */
22
23 #include <vppinfra/vec.h>
24 #include <vnet/vnet.h>
25 #include <vnet/ip/ip.h>
26 #include <vppinfra/bihash_48_8.h>
27 #include <vnet/ip/ip6_reassembly.h>
28
29 #define MSEC_PER_SEC 1000
30 #define IP6_REASS_TIMEOUT_DEFAULT_MS 100
31 #define IP6_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS 10000 // 10 seconds default
32 #define IP6_REASS_MAX_REASSEMBLIES_DEFAULT 1024
33 #define IP6_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT 3
34 #define IP6_REASS_HT_LOAD_FACTOR (0.75)
35
36 typedef enum
37 {
38   IP6_REASS_RC_OK,
39   IP6_REASS_RC_INTERNAL_ERROR,
40   IP6_REASS_RC_TOO_MANY_FRAGMENTS,
41   IP6_REASS_RC_NO_BUF,
42   IP6_REASS_RC_HANDOFF,
43 } ip6_reass_rc_t;
44
45 typedef struct
46 {
47   union
48   {
49     struct
50     {
51       ip6_address_t src;
52       ip6_address_t dst;
53       u32 xx_id;
54       u32 frag_id;
55       u8 unused[7];
56       u8 proto;
57     };
58     u64 as_u64[6];
59   };
60 } ip6_reass_key_t;
61
62 typedef union
63 {
64   struct
65   {
66     u32 reass_index;
67     u32 memory_owner_thread_index;
68   };
69   u64 as_u64;
70 } ip6_reass_val_t;
71
72 typedef union
73 {
74   struct
75   {
76     ip6_reass_key_t k;
77     ip6_reass_val_t v;
78   };
79   clib_bihash_kv_48_8_t kv;
80 } ip6_reass_kv_t;
81
82
83 always_inline u32
84 ip6_reass_buffer_get_data_offset (vlib_buffer_t * b)
85 {
86   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
87   return vnb->ip.reass.range_first - vnb->ip.reass.fragment_first;
88 }
89
90 always_inline u16
91 ip6_reass_buffer_get_data_len (vlib_buffer_t * b)
92 {
93   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
94   return clib_min (vnb->ip.reass.range_last, vnb->ip.reass.fragment_last) -
95     (vnb->ip.reass.fragment_first + ip6_reass_buffer_get_data_offset (b)) + 1;
96 }
97
98 typedef struct
99 {
100   // hash table key
101   ip6_reass_key_t key;
102   // time when last packet was received
103   f64 last_heard;
104   // internal id of this reassembly
105   u64 id;
106   // buffer index of first buffer in this reassembly context
107   u32 first_bi;
108   // last octet of packet, ~0 until fragment without more_fragments arrives
109   u32 last_packet_octet;
110   // length of data collected so far
111   u32 data_len;
112   // trace operation counter
113   u32 trace_op_counter;
114   // next index - used by custom apps (~0 if not set)
115   u32 next_index;
116   // error next index - used by custom apps (~0 if not set)
117   u32 error_next_index;
118   // minimum fragment length for this reassembly - used to estimate MTU
119   u16 min_fragment_length;
120   // number of fragments for this reassembly
121   u32 fragments_n;
122   // thread owning memory for this context (whose pool contains this ctx)
123   u32 memory_owner_thread_index;
124   // thread which received fragment with offset 0 and which sends out the
125   // completed reassembly
126   u32 sendout_thread_index;
127 } ip6_reass_t;
128
129 typedef struct
130 {
131   ip6_reass_t *pool;
132   u32 reass_n;
133   u32 id_counter;
134   clib_spinlock_t lock;
135 } ip6_reass_per_thread_t;
136
137 typedef struct
138 {
139   // IPv6 config
140   u32 timeout_ms;
141   f64 timeout;
142   u32 expire_walk_interval_ms;
143   // maximum number of fragments in one reassembly
144   u32 max_reass_len;
145   // maximum number of reassemblies
146   u32 max_reass_n;
147
148   // IPv6 runtime
149   clib_bihash_48_8_t hash;
150
151   // per-thread data
152   ip6_reass_per_thread_t *per_thread_data;
153
154   // convenience
155   vlib_main_t *vlib_main;
156
157   // node index of ip6-drop node
158   u32 ip6_drop_idx;
159   u32 ip6_icmp_error_idx;
160   u32 ip6_reass_expire_node_idx;
161
162   /** Worker handoff */
163   u32 fq_index;
164   u32 fq_feature_index;
165
166 } ip6_reass_main_t;
167
168 extern ip6_reass_main_t ip6_reass_main;
169
170 #ifndef CLIB_MARCH_VARIANT
171 ip6_reass_main_t ip6_reass_main;
172 #endif /* CLIB_MARCH_VARIANT */
173
174 typedef enum
175 {
176   IP6_REASSEMBLY_NEXT_INPUT,
177   IP6_REASSEMBLY_NEXT_DROP,
178   IP6_REASSEMBLY_NEXT_ICMP_ERROR,
179   IP6_REASSEMBLY_NEXT_HANDOFF,
180   IP6_REASSEMBLY_N_NEXT,
181 } ip6_reass_next_t;
182
183 typedef enum
184 {
185   RANGE_NEW,
186   RANGE_OVERLAP,
187   ICMP_ERROR_RT_EXCEEDED,
188   ICMP_ERROR_FL_TOO_BIG,
189   ICMP_ERROR_FL_NOT_MULT_8,
190   FINALIZE,
191   HANDOFF,
192 } ip6_reass_trace_operation_e;
193
194 typedef struct
195 {
196   u16 range_first;
197   u16 range_last;
198   u32 range_bi;
199   i32 data_offset;
200   u32 data_len;
201   u32 first_bi;
202 } ip6_reass_range_trace_t;
203
204 typedef struct
205 {
206   ip6_reass_trace_operation_e action;
207   u32 reass_id;
208   ip6_reass_range_trace_t trace_range;
209   u32 op_id;
210   u32 fragment_first;
211   u32 fragment_last;
212   u32 total_data_len;
213   u32 thread_id;
214   u32 thread_id_to;
215 } ip6_reass_trace_t;
216
217 static void
218 ip6_reass_trace_details (vlib_main_t * vm, u32 bi,
219                          ip6_reass_range_trace_t * trace)
220 {
221   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
222   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
223   trace->range_first = vnb->ip.reass.range_first;
224   trace->range_last = vnb->ip.reass.range_last;
225   trace->data_offset = ip6_reass_buffer_get_data_offset (b);
226   trace->data_len = ip6_reass_buffer_get_data_len (b);
227   trace->range_bi = bi;
228 }
229
230 static u8 *
231 format_ip6_reass_range_trace (u8 * s, va_list * args)
232 {
233   ip6_reass_range_trace_t *trace = va_arg (*args, ip6_reass_range_trace_t *);
234   s = format (s, "range: [%u, %u], off %d, len %u, bi %u", trace->range_first,
235               trace->range_last, trace->data_offset, trace->data_len,
236               trace->range_bi);
237   return s;
238 }
239
240 static u8 *
241 format_ip6_reass_trace (u8 * s, va_list * args)
242 {
243   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
244   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
245   ip6_reass_trace_t *t = va_arg (*args, ip6_reass_trace_t *);
246   u32 indent = 0;
247   if (~0 != t->reass_id)
248     {
249       s = format (s, "reass id: %u, op id: %u ", t->reass_id, t->op_id);
250       indent = format_get_indent (s);
251       s = format (s, "first bi: %u, data len: %u, ip/fragment[%u, %u]",
252                   t->trace_range.first_bi, t->total_data_len,
253                   t->fragment_first, t->fragment_last);
254     }
255   switch (t->action)
256     {
257     case RANGE_NEW:
258       s = format (s, "\n%Unew %U", format_white_space, indent,
259                   format_ip6_reass_range_trace, &t->trace_range);
260       break;
261     case RANGE_OVERLAP:
262       s = format (s, "\n%Uoverlap %U", format_white_space, indent,
263                   format_ip6_reass_range_trace, &t->trace_range);
264       break;
265     case ICMP_ERROR_FL_TOO_BIG:
266       s = format (s, "\n%Uicmp-error - frag_len > 65535 %U",
267                   format_white_space, indent, format_ip6_reass_range_trace,
268                   &t->trace_range);
269       break;
270     case ICMP_ERROR_FL_NOT_MULT_8:
271       s = format (s, "\n%Uicmp-error - frag_len mod 8 != 0 %U",
272                   format_white_space, indent, format_ip6_reass_range_trace,
273                   &t->trace_range);
274       break;
275     case ICMP_ERROR_RT_EXCEEDED:
276       s = format (s, "\n%Uicmp-error - reassembly time exceeded",
277                   format_white_space, indent);
278       break;
279     case FINALIZE:
280       s = format (s, "\n%Ufinalize reassembly", format_white_space, indent);
281       break;
282     case HANDOFF:
283       s =
284         format (s, "handoff from thread #%u to thread #%u", t->thread_id,
285                 t->thread_id_to);
286       break;
287     }
288   return s;
289 }
290
291 static void
292 ip6_reass_add_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
293                      ip6_reass_main_t * rm, u32 reass_id, u32 op_id,
294                      u32 bi, u32 first_bi, u32 data_len,
295                      ip6_reass_trace_operation_e action, u32 thread_id_to)
296 {
297   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
298   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
299   ip6_reass_trace_t *t = vlib_add_trace (vm, node, b, sizeof (t[0]));
300   t->reass_id = reass_id;
301   t->action = action;
302   ip6_reass_trace_details (vm, bi, &t->trace_range);
303   t->op_id = op_id;
304   t->thread_id = vm->thread_index;
305   t->thread_id_to = thread_id_to;
306   t->fragment_first = vnb->ip.reass.fragment_first;
307   t->fragment_last = vnb->ip.reass.fragment_last;
308   t->trace_range.first_bi = first_bi;
309   t->total_data_len = data_len;
310 #if 0
311   static u8 *s = NULL;
312   s = format (s, "%U", format_ip6_reass_trace, NULL, NULL, t);
313   printf ("%.*s\n", vec_len (s), s);
314   fflush (stdout);
315   vec_reset_length (s);
316 #endif
317 }
318
319 always_inline void
320 ip6_reass_free_ctx (ip6_reass_per_thread_t * rt, ip6_reass_t * reass)
321 {
322   pool_put (rt->pool, reass);
323   --rt->reass_n;
324 }
325
326 always_inline void
327 ip6_reass_free (ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
328                 ip6_reass_t * reass)
329 {
330   clib_bihash_kv_48_8_t kv;
331   kv.key[0] = reass->key.as_u64[0];
332   kv.key[1] = reass->key.as_u64[1];
333   kv.key[2] = reass->key.as_u64[2];
334   kv.key[3] = reass->key.as_u64[3];
335   kv.key[4] = reass->key.as_u64[4];
336   kv.key[5] = reass->key.as_u64[5];
337   clib_bihash_add_del_48_8 (&rm->hash, &kv, 0);
338   ip6_reass_free_ctx (rt, reass);
339 }
340
341 always_inline void
342 ip6_reass_drop_all (vlib_main_t * vm, vlib_node_runtime_t * node,
343                     ip6_reass_main_t * rm, ip6_reass_t * reass)
344 {
345   u32 range_bi = reass->first_bi;
346   vlib_buffer_t *range_b;
347   vnet_buffer_opaque_t *range_vnb;
348   u32 *to_free = NULL;
349   while (~0 != range_bi)
350     {
351       range_b = vlib_get_buffer (vm, range_bi);
352       range_vnb = vnet_buffer (range_b);
353       u32 bi = range_bi;
354       while (~0 != bi)
355         {
356           vec_add1 (to_free, bi);
357           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
358           if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
359             {
360               bi = b->next_buffer;
361               b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
362             }
363           else
364             {
365               bi = ~0;
366             }
367         }
368       range_bi = range_vnb->ip.reass.next_range_bi;
369     }
370   /* send to next_error_index */
371   if (~0 != reass->error_next_index)
372     {
373       u32 n_left_to_next, *to_next, next_index;
374
375       next_index = reass->error_next_index;
376       u32 bi = ~0;
377
378       while (vec_len (to_free) > 0)
379         {
380           vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
381
382           while (vec_len (to_free) > 0 && n_left_to_next > 0)
383             {
384               bi = vec_pop (to_free);
385
386               if (~0 != bi)
387                 {
388                   to_next[0] = bi;
389                   to_next += 1;
390                   n_left_to_next -= 1;
391                   vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
392                                                    to_next, n_left_to_next,
393                                                    bi, next_index);
394                 }
395             }
396           vlib_put_next_frame (vm, node, next_index, n_left_to_next);
397         }
398     }
399   else
400     {
401       vlib_buffer_free (vm, to_free, vec_len (to_free));
402     }
403   vec_free (to_free);
404 }
405
406 always_inline void
407 ip6_reass_on_timeout (vlib_main_t * vm, vlib_node_runtime_t * node,
408                       ip6_reass_main_t * rm, ip6_reass_t * reass,
409                       u32 * icmp_bi)
410 {
411   if (~0 == reass->first_bi)
412     {
413       return;
414     }
415   if (~0 == reass->next_index)  // custom apps don't want icmp
416     {
417       vlib_buffer_t *b = vlib_get_buffer (vm, reass->first_bi);
418       if (0 == vnet_buffer (b)->ip.reass.fragment_first)
419         {
420           *icmp_bi = reass->first_bi;
421           if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
422             {
423               ip6_reass_add_trace (vm, node, rm, reass->id,
424                                    reass->trace_op_counter, reass->first_bi,
425                                    reass->first_bi, reass->data_len,
426                                    ICMP_ERROR_RT_EXCEEDED, ~0);
427               ++reass->trace_op_counter;
428             }
429           // fragment with offset zero received - send icmp message back
430           if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
431             {
432               // separate first buffer from chain and steer it towards icmp node
433               b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
434               reass->first_bi = b->next_buffer;
435             }
436           else
437             {
438               reass->first_bi = vnet_buffer (b)->ip.reass.next_range_bi;
439             }
440           icmp6_error_set_vnet_buffer (b, ICMP6_time_exceeded,
441                                        ICMP6_time_exceeded_fragment_reassembly_time_exceeded,
442                                        0);
443         }
444     }
445   ip6_reass_drop_all (vm, node, rm, reass);
446 }
447
448 always_inline ip6_reass_t *
449 ip6_reass_find_or_create (vlib_main_t * vm, vlib_node_runtime_t * node,
450                           ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
451                           ip6_reass_kv_t * kv, u32 * icmp_bi, u8 * do_handoff)
452 {
453   ip6_reass_t *reass;
454   f64 now;
455
456 again:
457
458   reass = NULL;
459   now = vlib_time_now (vm);
460
461   if (!clib_bihash_search_48_8
462       (&rm->hash, (clib_bihash_kv_48_8_t *) kv, (clib_bihash_kv_48_8_t *) kv))
463     {
464       reass =
465         pool_elt_at_index (rm->per_thread_data
466                            [kv->v.memory_owner_thread_index].pool,
467                            kv->v.reass_index);
468       if (vm->thread_index != kv->v.memory_owner_thread_index)
469         {
470           *do_handoff = 1;
471           return reass;
472         }
473
474       if (now > reass->last_heard + rm->timeout)
475         {
476           ip6_reass_on_timeout (vm, node, rm, reass, icmp_bi);
477           ip6_reass_free (rm, rt, reass);
478           reass = NULL;
479         }
480     }
481
482   if (reass)
483     {
484       reass->last_heard = now;
485       return reass;
486     }
487
488   if (rt->reass_n >= rm->max_reass_n)
489     {
490       reass = NULL;
491       return reass;
492     }
493   else
494     {
495       pool_get (rt->pool, reass);
496       clib_memset (reass, 0, sizeof (*reass));
497       reass->id = ((u64) vm->thread_index * 1000000000) + rt->id_counter;
498       ++rt->id_counter;
499       reass->first_bi = ~0;
500       reass->last_packet_octet = ~0;
501       reass->data_len = 0;
502       reass->next_index = ~0;
503       reass->error_next_index = ~0;
504       ++rt->reass_n;
505     }
506
507   reass->key.as_u64[0] = ((clib_bihash_kv_48_8_t *) kv)->key[0];
508   reass->key.as_u64[1] = ((clib_bihash_kv_48_8_t *) kv)->key[1];
509   reass->key.as_u64[2] = ((clib_bihash_kv_48_8_t *) kv)->key[2];
510   reass->key.as_u64[3] = ((clib_bihash_kv_48_8_t *) kv)->key[3];
511   reass->key.as_u64[4] = ((clib_bihash_kv_48_8_t *) kv)->key[4];
512   reass->key.as_u64[5] = ((clib_bihash_kv_48_8_t *) kv)->key[5];
513   kv->v.reass_index = (reass - rt->pool);
514   kv->v.memory_owner_thread_index = vm->thread_index;
515   reass->last_heard = now;
516
517   int rv =
518     clib_bihash_add_del_48_8 (&rm->hash, (clib_bihash_kv_48_8_t *) kv, 2);
519   if (rv)
520     {
521       ip6_reass_free_ctx (rt, reass);
522       reass = NULL;
523       // if other worker created a context already work with the other copy
524       if (-2 == rv)
525         goto again;
526     }
527
528   return reass;
529 }
530
531 always_inline ip6_reass_rc_t
532 ip6_reass_finalize (vlib_main_t * vm, vlib_node_runtime_t * node,
533                     ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
534                     ip6_reass_t * reass, u32 * bi0, u32 * next0, u32 * error0,
535                     bool is_custom_app)
536 {
537   *bi0 = reass->first_bi;
538   *error0 = IP6_ERROR_NONE;
539   ip6_frag_hdr_t *frag_hdr;
540   vlib_buffer_t *last_b = NULL;
541   u32 sub_chain_bi = reass->first_bi;
542   u32 total_length = 0;
543   u32 buf_cnt = 0;
544   u32 dropped_cnt = 0;
545   u32 *vec_drop_compress = NULL;
546   ip6_reass_rc_t rv = IP6_REASS_RC_OK;
547   do
548     {
549       u32 tmp_bi = sub_chain_bi;
550       vlib_buffer_t *tmp = vlib_get_buffer (vm, tmp_bi);
551       vnet_buffer_opaque_t *vnb = vnet_buffer (tmp);
552       if (!(vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first) &&
553           !(vnb->ip.reass.range_last > vnb->ip.reass.fragment_first))
554         {
555           rv = IP6_REASS_RC_INTERNAL_ERROR;
556           goto free_buffers_and_return;
557         }
558
559       u32 data_len = ip6_reass_buffer_get_data_len (tmp);
560       u32 trim_front = vnet_buffer (tmp)->ip.reass.ip6_frag_hdr_offset +
561         sizeof (*frag_hdr) + ip6_reass_buffer_get_data_offset (tmp);
562       u32 trim_end =
563         vlib_buffer_length_in_chain (vm, tmp) - trim_front - data_len;
564       if (tmp_bi == reass->first_bi)
565         {
566           /* first buffer - keep ip6 header */
567           if (0 != ip6_reass_buffer_get_data_offset (tmp))
568             {
569               rv = IP6_REASS_RC_INTERNAL_ERROR;
570               goto free_buffers_and_return;
571             }
572           trim_front = 0;
573           trim_end = vlib_buffer_length_in_chain (vm, tmp) - data_len -
574             (vnet_buffer (tmp)->ip.reass.ip6_frag_hdr_offset +
575              sizeof (*frag_hdr));
576           if (!(vlib_buffer_length_in_chain (vm, tmp) - trim_end > 0))
577             {
578               rv = IP6_REASS_RC_INTERNAL_ERROR;
579               goto free_buffers_and_return;
580             }
581         }
582       u32 keep_data =
583         vlib_buffer_length_in_chain (vm, tmp) - trim_front - trim_end;
584       while (1)
585         {
586           ++buf_cnt;
587           if (trim_front)
588             {
589               if (trim_front > tmp->current_length)
590                 {
591                   /* drop whole buffer */
592                   vec_add1 (vec_drop_compress, tmp_bi);
593                   trim_front -= tmp->current_length;
594                   if (!(tmp->flags & VLIB_BUFFER_NEXT_PRESENT))
595                     {
596                       rv = IP6_REASS_RC_INTERNAL_ERROR;
597                       goto free_buffers_and_return;
598                     }
599                   tmp->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
600                   tmp_bi = tmp->next_buffer;
601                   tmp = vlib_get_buffer (vm, tmp_bi);
602                   continue;
603                 }
604               else
605                 {
606                   vlib_buffer_advance (tmp, trim_front);
607                   trim_front = 0;
608                 }
609             }
610           if (keep_data)
611             {
612               if (last_b)
613                 {
614                   last_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
615                   last_b->next_buffer = tmp_bi;
616                 }
617               last_b = tmp;
618               if (keep_data <= tmp->current_length)
619                 {
620                   tmp->current_length = keep_data;
621                   keep_data = 0;
622                 }
623               else
624                 {
625                   keep_data -= tmp->current_length;
626                   if (!(tmp->flags & VLIB_BUFFER_NEXT_PRESENT))
627                     {
628                       rv = IP6_REASS_RC_INTERNAL_ERROR;
629                       goto free_buffers_and_return;
630                     }
631                 }
632               total_length += tmp->current_length;
633             }
634           else
635             {
636               vec_add1 (vec_drop_compress, tmp_bi);
637               if (reass->first_bi == tmp_bi)
638                 {
639                   rv = IP6_REASS_RC_INTERNAL_ERROR;
640                   goto free_buffers_and_return;
641                 }
642               ++dropped_cnt;
643             }
644           if (tmp->flags & VLIB_BUFFER_NEXT_PRESENT)
645             {
646               tmp_bi = tmp->next_buffer;
647               tmp = vlib_get_buffer (vm, tmp->next_buffer);
648             }
649           else
650             {
651               break;
652             }
653         }
654       sub_chain_bi =
655         vnet_buffer (vlib_get_buffer (vm, sub_chain_bi))->ip.
656         reass.next_range_bi;
657     }
658   while (~0 != sub_chain_bi);
659
660   if (!last_b)
661     {
662       rv = IP6_REASS_RC_INTERNAL_ERROR;
663       goto free_buffers_and_return;
664     }
665   last_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
666   vlib_buffer_t *first_b = vlib_get_buffer (vm, reass->first_bi);
667   if (total_length < first_b->current_length)
668     {
669       rv = IP6_REASS_RC_INTERNAL_ERROR;
670       goto free_buffers_and_return;
671     }
672   total_length -= first_b->current_length;
673   first_b->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
674   first_b->total_length_not_including_first_buffer = total_length;
675   // drop fragment header
676   vnet_buffer_opaque_t *first_b_vnb = vnet_buffer (first_b);
677   ip6_header_t *ip = vlib_buffer_get_current (first_b);
678   u16 ip6_frag_hdr_offset = first_b_vnb->ip.reass.ip6_frag_hdr_offset;
679   ip6_ext_header_t *prev_hdr;
680   ip6_ext_header_find_t (ip, prev_hdr, frag_hdr,
681                          IP_PROTOCOL_IPV6_FRAGMENTATION);
682   if (prev_hdr)
683     {
684       prev_hdr->next_hdr = frag_hdr->next_hdr;
685     }
686   else
687     {
688       ip->protocol = frag_hdr->next_hdr;
689     }
690   if (!((u8 *) frag_hdr - (u8 *) ip == ip6_frag_hdr_offset))
691     {
692       rv = IP6_REASS_RC_INTERNAL_ERROR;
693       goto free_buffers_and_return;
694     }
695   memmove (frag_hdr, (u8 *) frag_hdr + sizeof (*frag_hdr),
696            first_b->current_length - ip6_frag_hdr_offset -
697            sizeof (ip6_frag_hdr_t));
698   first_b->current_length -= sizeof (*frag_hdr);
699   ip->payload_length =
700     clib_host_to_net_u16 (total_length + first_b->current_length -
701                           sizeof (*ip));
702   if (!vlib_buffer_chain_linearize (vm, first_b))
703     {
704       rv = IP6_REASS_RC_NO_BUF;
705       goto free_buffers_and_return;
706     }
707   first_b->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
708   if (PREDICT_FALSE (first_b->flags & VLIB_BUFFER_IS_TRACED))
709     {
710       ip6_reass_add_trace (vm, node, rm, reass->id, reass->trace_op_counter,
711                            reass->first_bi, reass->first_bi, reass->data_len,
712                            FINALIZE, ~0);
713       ++reass->trace_op_counter;
714 #if 0
715       // following code does a hexdump of packet fragments to stdout ...
716       do
717         {
718           u32 bi = reass->first_bi;
719           u8 *s = NULL;
720           while (~0 != bi)
721             {
722               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
723               s = format (s, "%u: %U\n", bi, format_hexdump,
724                           vlib_buffer_get_current (b), b->current_length);
725               if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
726                 {
727                   bi = b->next_buffer;
728                 }
729               else
730                 {
731                   break;
732                 }
733             }
734           printf ("%.*s\n", vec_len (s), s);
735           fflush (stdout);
736           vec_free (s);
737         }
738       while (0);
739 #endif
740     }
741   if (!is_custom_app)
742     {
743       *next0 = IP6_REASSEMBLY_NEXT_INPUT;
744     }
745   else
746     {
747       *next0 = reass->next_index;
748     }
749   vnet_buffer (first_b)->ip.reass.estimated_mtu = reass->min_fragment_length;
750   ip6_reass_free (rm, rt, reass);
751   reass = NULL;
752 free_buffers_and_return:
753   vlib_buffer_free (vm, vec_drop_compress, vec_len (vec_drop_compress));
754   vec_free (vec_drop_compress);
755   return rv;
756 }
757
758 always_inline void
759 ip6_reass_insert_range_in_chain (vlib_main_t * vm, ip6_reass_main_t * rm,
760                                  ip6_reass_per_thread_t * rt,
761                                  ip6_reass_t * reass, u32 prev_range_bi,
762                                  u32 new_next_bi)
763 {
764
765   vlib_buffer_t *new_next_b = vlib_get_buffer (vm, new_next_bi);
766   vnet_buffer_opaque_t *new_next_vnb = vnet_buffer (new_next_b);
767   if (~0 != prev_range_bi)
768     {
769       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
770       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
771       new_next_vnb->ip.reass.next_range_bi = prev_vnb->ip.reass.next_range_bi;
772       prev_vnb->ip.reass.next_range_bi = new_next_bi;
773     }
774   else
775     {
776       if (~0 != reass->first_bi)
777         {
778           new_next_vnb->ip.reass.next_range_bi = reass->first_bi;
779         }
780       reass->first_bi = new_next_bi;
781     }
782   reass->data_len += ip6_reass_buffer_get_data_len (new_next_b);
783 }
784
785 always_inline ip6_reass_rc_t
786 ip6_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
787                   ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
788                   ip6_reass_t * reass, u32 * bi0, u32 * next0, u32 * error0,
789                   ip6_frag_hdr_t * frag_hdr, bool is_custom_app,
790                   u32 * handoff_thread_idx)
791 {
792   int consumed = 0;
793   vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
794   vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
795   if (is_custom_app)
796     {
797       reass->next_index = fvnb->ip.reass.next_index;    // store next_index before it's overwritten
798       reass->error_next_index = fvnb->ip.reass.error_next_index;        // store error_next_index before it is overwritten
799     }
800
801   fvnb->ip.reass.ip6_frag_hdr_offset =
802     (u8 *) frag_hdr - (u8 *) vlib_buffer_get_current (fb);
803   ip6_header_t *fip = vlib_buffer_get_current (fb);
804   if (fb->current_length < sizeof (*fip) ||
805       fvnb->ip.reass.ip6_frag_hdr_offset == 0 ||
806       fvnb->ip.reass.ip6_frag_hdr_offset >= fb->current_length)
807     {
808       return IP6_REASS_RC_INTERNAL_ERROR;
809     }
810
811   u32 fragment_first = fvnb->ip.reass.fragment_first =
812     ip6_frag_hdr_offset_bytes (frag_hdr);
813   u32 fragment_length =
814     vlib_buffer_length_in_chain (vm, fb) -
815     (fvnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
816   u32 fragment_last = fvnb->ip.reass.fragment_last =
817     fragment_first + fragment_length - 1;
818   int more_fragments = ip6_frag_hdr_more (frag_hdr);
819   u32 candidate_range_bi = reass->first_bi;
820   u32 prev_range_bi = ~0;
821   fvnb->ip.reass.range_first = fragment_first;
822   fvnb->ip.reass.range_last = fragment_last;
823   fvnb->ip.reass.next_range_bi = ~0;
824   if (!more_fragments)
825     {
826       reass->last_packet_octet = fragment_last;
827     }
828   if (~0 == reass->first_bi)
829     {
830       // starting a new reassembly
831       ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
832                                        *bi0);
833       reass->min_fragment_length = clib_net_to_host_u16 (fip->payload_length);
834       consumed = 1;
835       reass->fragments_n = 1;
836       goto check_if_done_maybe;
837     }
838   reass->min_fragment_length =
839     clib_min (clib_net_to_host_u16 (fip->payload_length),
840               fvnb->ip.reass.estimated_mtu);
841   while (~0 != candidate_range_bi)
842     {
843       vlib_buffer_t *candidate_b = vlib_get_buffer (vm, candidate_range_bi);
844       vnet_buffer_opaque_t *candidate_vnb = vnet_buffer (candidate_b);
845       if (fragment_first > candidate_vnb->ip.reass.range_last)
846         {
847           // this fragments starts after candidate range
848           prev_range_bi = candidate_range_bi;
849           candidate_range_bi = candidate_vnb->ip.reass.next_range_bi;
850           if (candidate_vnb->ip.reass.range_last < fragment_last &&
851               ~0 == candidate_range_bi)
852             {
853               // special case - this fragment falls beyond all known ranges
854               ip6_reass_insert_range_in_chain (vm, rm, rt, reass,
855                                                prev_range_bi, *bi0);
856               consumed = 1;
857               break;
858             }
859           continue;
860         }
861       if (fragment_last < candidate_vnb->ip.reass.range_first)
862         {
863           // this fragment ends before candidate range without any overlap
864           ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
865                                            *bi0);
866           consumed = 1;
867         }
868       else if (fragment_first == candidate_vnb->ip.reass.range_first &&
869                fragment_last == candidate_vnb->ip.reass.range_last)
870         {
871           // duplicate fragment - ignore
872         }
873       else
874         {
875           // overlapping fragment - not allowed by RFC 8200
876           ip6_reass_drop_all (vm, node, rm, reass);
877           ip6_reass_free (rm, rt, reass);
878           if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
879             {
880               ip6_reass_add_trace (vm, node, rm, reass->id,
881                                    reass->trace_op_counter, *bi0,
882                                    reass->first_bi, reass->data_len,
883                                    RANGE_OVERLAP, ~0);
884               ++reass->trace_op_counter;
885             }
886           *next0 = IP6_REASSEMBLY_NEXT_DROP;
887           *error0 = IP6_ERROR_REASS_OVERLAPPING_FRAGMENT;
888           return IP6_REASS_RC_OK;
889         }
890       break;
891     }
892   ++reass->fragments_n;
893 check_if_done_maybe:
894   if (consumed)
895     {
896       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
897         {
898           ip6_reass_add_trace (vm, node, rm, reass->id,
899                                reass->trace_op_counter, *bi0, reass->first_bi,
900                                reass->data_len, RANGE_NEW, ~0);
901           ++reass->trace_op_counter;
902         }
903     }
904   if (~0 != reass->last_packet_octet &&
905       reass->data_len == reass->last_packet_octet + 1)
906     {
907       return ip6_reass_finalize (vm, node, rm, rt, reass, bi0, next0, error0,
908                                  is_custom_app);
909       *handoff_thread_idx = reass->sendout_thread_index;
910       ip6_reass_rc_t rc =
911         ip6_reass_finalize (vm, node, rm, rt, reass, bi0, next0, error0,
912                             is_custom_app);
913       if (IP6_REASS_RC_OK == rc
914           && reass->memory_owner_thread_index != reass->sendout_thread_index)
915         {
916           return IP6_REASS_RC_HANDOFF;
917         }
918       return rc;
919     }
920   else
921     {
922       if (consumed)
923         {
924           *bi0 = ~0;
925           if (reass->fragments_n > rm->max_reass_len)
926             {
927               return IP6_REASS_RC_TOO_MANY_FRAGMENTS;
928             }
929         }
930       else
931         {
932           *next0 = IP6_REASSEMBLY_NEXT_DROP;
933           *error0 = IP6_ERROR_REASS_DUPLICATE_FRAGMENT;
934         }
935     }
936   return IP6_REASS_RC_OK;
937 }
938
939 always_inline bool
940 ip6_reass_verify_upper_layer_present (vlib_node_runtime_t * node,
941                                       vlib_buffer_t * b,
942                                       ip6_frag_hdr_t * frag_hdr)
943 {
944   ip6_ext_header_t *tmp = (ip6_ext_header_t *) frag_hdr;
945   while (ip6_ext_hdr (tmp->next_hdr))
946     {
947       tmp = ip6_ext_next_header (tmp);
948     }
949   if (IP_PROTOCOL_IP6_NONXT == tmp->next_hdr)
950     {
951       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
952                                    ICMP6_parameter_problem_first_fragment_has_incomplete_header_chain,
953                                    0);
954       b->error = node->errors[IP6_ERROR_REASS_MISSING_UPPER];
955
956       return false;
957     }
958   return true;
959 }
960
961 always_inline bool
962 ip6_reass_verify_fragment_multiple_8 (vlib_main_t * vm,
963                                       vlib_node_runtime_t * node,
964                                       vlib_buffer_t * b,
965                                       ip6_frag_hdr_t * frag_hdr)
966 {
967   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
968   ip6_header_t *ip = vlib_buffer_get_current (b);
969   int more_fragments = ip6_frag_hdr_more (frag_hdr);
970   u32 fragment_length =
971     vlib_buffer_length_in_chain (vm, b) -
972     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
973   if (more_fragments && 0 != fragment_length % 8)
974     {
975       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
976                                    ICMP6_parameter_problem_erroneous_header_field,
977                                    (u8 *) & ip->payload_length - (u8 *) ip);
978       return false;
979     }
980   return true;
981 }
982
983 always_inline bool
984 ip6_reass_verify_packet_size_lt_64k (vlib_main_t * vm,
985                                      vlib_node_runtime_t * node,
986                                      vlib_buffer_t * b,
987                                      ip6_frag_hdr_t * frag_hdr)
988 {
989   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
990   u32 fragment_first = ip6_frag_hdr_offset_bytes (frag_hdr);
991   u32 fragment_length =
992     vlib_buffer_length_in_chain (vm, b) -
993     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
994   if (fragment_first + fragment_length > 65535)
995     {
996       ip6_header_t *ip0 = vlib_buffer_get_current (b);
997       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
998                                    ICMP6_parameter_problem_erroneous_header_field,
999                                    (u8 *) & frag_hdr->fragment_offset_and_more
1000                                    - (u8 *) ip0);
1001       return false;
1002     }
1003   return true;
1004 }
1005
1006 always_inline uword
1007 ip6_reassembly_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1008                        vlib_frame_t * frame, bool is_feature,
1009                        bool is_custom_app)
1010 {
1011   u32 *from = vlib_frame_vector_args (frame);
1012   u32 n_left_from, n_left_to_next, *to_next, next_index;
1013   ip6_reass_main_t *rm = &ip6_reass_main;
1014   ip6_reass_per_thread_t *rt = &rm->per_thread_data[vm->thread_index];
1015   clib_spinlock_lock (&rt->lock);
1016
1017   n_left_from = frame->n_vectors;
1018   next_index = node->cached_next_index;
1019   while (n_left_from > 0)
1020     {
1021       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1022
1023       while (n_left_from > 0 && n_left_to_next > 0)
1024         {
1025           u32 bi0;
1026           vlib_buffer_t *b0;
1027           u32 next0 = IP6_REASSEMBLY_NEXT_DROP;
1028           u32 error0 = IP6_ERROR_NONE;
1029           u32 icmp_bi = ~0;
1030
1031           bi0 = from[0];
1032           b0 = vlib_get_buffer (vm, bi0);
1033
1034           ip6_header_t *ip0 = vlib_buffer_get_current (b0);
1035           ip6_frag_hdr_t *frag_hdr = NULL;
1036           ip6_ext_header_t *prev_hdr;
1037           if (ip6_ext_hdr (ip0->protocol))
1038             {
1039               ip6_ext_header_find_t (ip0, prev_hdr, frag_hdr,
1040                                      IP_PROTOCOL_IPV6_FRAGMENTATION);
1041             }
1042           if (!frag_hdr)
1043             {
1044               // this is a regular packet - no fragmentation
1045               next0 = IP6_REASSEMBLY_NEXT_INPUT;
1046               goto skip_reass;
1047             }
1048           if (0 == ip6_frag_hdr_offset (frag_hdr))
1049             {
1050               // first fragment - verify upper-layer is present
1051               if (!ip6_reass_verify_upper_layer_present (node, b0, frag_hdr))
1052                 {
1053                   next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
1054                   goto skip_reass;
1055                 }
1056             }
1057           if (!ip6_reass_verify_fragment_multiple_8 (vm, node, b0, frag_hdr)
1058               || !ip6_reass_verify_packet_size_lt_64k (vm, node, b0,
1059                                                        frag_hdr))
1060             {
1061               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
1062               goto skip_reass;
1063             }
1064           vnet_buffer (b0)->ip.reass.ip6_frag_hdr_offset =
1065             (u8 *) frag_hdr - (u8 *) ip0;
1066
1067           ip6_reass_kv_t kv;
1068           u8 do_handoff = 0;
1069
1070           kv.k.as_u64[0] = ip0->src_address.as_u64[0];
1071           kv.k.as_u64[1] = ip0->src_address.as_u64[1];
1072           kv.k.as_u64[2] = ip0->dst_address.as_u64[0];
1073           kv.k.as_u64[3] = ip0->dst_address.as_u64[1];
1074           kv.k.as_u64[4] =
1075             ((u64) vec_elt (ip6_main.fib_index_by_sw_if_index,
1076                             vnet_buffer (b0)->sw_if_index[VLIB_RX])) << 32 |
1077             (u64) frag_hdr->identification;
1078           kv.k.as_u64[5] = ip0->protocol;
1079
1080           ip6_reass_t *reass =
1081             ip6_reass_find_or_create (vm, node, rm, rt, &kv, &icmp_bi,
1082                                       &do_handoff);
1083
1084           if (reass)
1085             {
1086               const u32 fragment_first = ip6_frag_hdr_offset (frag_hdr);
1087               if (0 == fragment_first)
1088                 {
1089                   reass->sendout_thread_index = vm->thread_index;
1090                 }
1091             }
1092           if (PREDICT_FALSE (do_handoff))
1093             {
1094               next0 = IP6_REASSEMBLY_NEXT_HANDOFF;
1095               if (is_feature)
1096                 vnet_buffer (b0)->ip.reass.owner_feature_thread_index =
1097                   kv.v.memory_owner_thread_index;
1098               else
1099                 vnet_buffer (b0)->ip.reass.owner_thread_index =
1100                   kv.v.memory_owner_thread_index;
1101             }
1102           else if (reass)
1103             {
1104               u32 handoff_thread_idx;
1105               switch (ip6_reass_update (vm, node, rm, rt, reass, &bi0, &next0,
1106                                         &error0, frag_hdr, is_custom_app,
1107                                         &handoff_thread_idx))
1108                 {
1109                 case IP6_REASS_RC_OK:
1110                   /* nothing to do here */
1111                   break;
1112                 case IP6_REASS_RC_HANDOFF:
1113                   next0 = IP6_REASSEMBLY_NEXT_HANDOFF;
1114                   b0 = vlib_get_buffer (vm, bi0);
1115                   if (is_feature)
1116                     vnet_buffer (b0)->ip.reass.owner_feature_thread_index =
1117                       handoff_thread_idx;
1118                   else
1119                     vnet_buffer (b0)->ip.reass.owner_thread_index =
1120                       handoff_thread_idx;
1121                   break;
1122                 case IP6_REASS_RC_TOO_MANY_FRAGMENTS:
1123                   vlib_node_increment_counter (vm, node->node_index,
1124                                                IP6_ERROR_REASS_FRAGMENT_CHAIN_TOO_LONG,
1125                                                1);
1126                   ip6_reass_drop_all (vm, node, rm, reass);
1127                   ip6_reass_free (rm, rt, reass);
1128                   goto next_packet;
1129                   break;
1130                 case IP6_REASS_RC_NO_BUF:
1131                   vlib_node_increment_counter (vm, node->node_index,
1132                                                IP6_ERROR_REASS_NO_BUF, 1);
1133                   ip6_reass_drop_all (vm, node, rm, reass);
1134                   ip6_reass_free (rm, rt, reass);
1135                   goto next_packet;
1136                   break;
1137                 case IP6_REASS_RC_INTERNAL_ERROR:
1138                   /* drop everything and start with a clean slate */
1139                   vlib_node_increment_counter (vm, node->node_index,
1140                                                IP6_ERROR_REASS_INTERNAL_ERROR,
1141                                                1);
1142                   ip6_reass_drop_all (vm, node, rm, reass);
1143                   ip6_reass_free (rm, rt, reass);
1144                   goto next_packet;
1145                   break;
1146                 }
1147             }
1148           else
1149             {
1150               if (is_feature)
1151                 {
1152                   next0 = IP6_REASSEMBLY_NEXT_DROP;
1153                 }
1154               else
1155                 {
1156                   vnet_buffer_opaque_t *fvnb = vnet_buffer (b0);
1157                   next0 = fvnb->ip.reass.error_next_index;
1158                 }
1159               error0 = IP6_ERROR_REASS_LIMIT_REACHED;
1160             }
1161
1162           b0->error = node->errors[error0];
1163
1164           if (~0 != bi0)
1165             {
1166             skip_reass:
1167               to_next[0] = bi0;
1168               to_next += 1;
1169               n_left_to_next -= 1;
1170               if (next0 == IP6_REASSEMBLY_NEXT_HANDOFF)
1171                 {
1172                   if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
1173                     {
1174                       if (is_feature)
1175                         ip6_reass_add_trace (vm, node, rm, ~0,
1176                                              ~0,
1177                                              bi0, ~0, ~0, HANDOFF,
1178                                              vnet_buffer (b0)->ip.
1179                                              reass.owner_feature_thread_index);
1180                       else
1181                         ip6_reass_add_trace (vm, node, rm, ~0, ~0, bi0,
1182                                              ~0, ~0, HANDOFF,
1183                                              vnet_buffer (b0)->ip.
1184                                              reass.owner_thread_index);
1185                     }
1186                 }
1187               else if (is_feature && IP6_ERROR_NONE == error0)
1188                 {
1189                   b0 = vlib_get_buffer (vm, bi0);
1190                   vnet_feature_next (&next0, b0);
1191                 }
1192               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1193                                                n_left_to_next, bi0, next0);
1194             }
1195
1196           if (~0 != icmp_bi)
1197             {
1198               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
1199               to_next[0] = icmp_bi;
1200               to_next += 1;
1201               n_left_to_next -= 1;
1202               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1203                                                n_left_to_next, icmp_bi,
1204                                                next0);
1205             }
1206         next_packet:
1207           from += 1;
1208           n_left_from -= 1;
1209         }
1210
1211       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1212     }
1213
1214   clib_spinlock_unlock (&rt->lock);
1215   return frame->n_vectors;
1216 }
1217
1218 static char *ip6_reassembly_error_strings[] = {
1219 #define _(sym, string) string,
1220   foreach_ip6_error
1221 #undef _
1222 };
1223
1224 VLIB_NODE_FN (ip6_reass_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
1225                                vlib_frame_t * frame)
1226 {
1227   return ip6_reassembly_inline (vm, node, frame, false /* is_feature */ ,
1228                                 false /* is_custom_app */ );
1229 }
1230
1231 /* *INDENT-OFF* */
1232 VLIB_REGISTER_NODE (ip6_reass_node) = {
1233     .name = "ip6-reassembly",
1234     .vector_size = sizeof (u32),
1235     .format_trace = format_ip6_reass_trace,
1236     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1237     .error_strings = ip6_reassembly_error_strings,
1238     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1239     .next_nodes =
1240         {
1241                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1242                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1243                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1244                 [IP6_REASSEMBLY_NEXT_HANDOFF] = "ip6-reassembly-handoff",
1245         },
1246 };
1247 /* *INDENT-ON* */
1248
1249 VLIB_NODE_FN (ip6_reass_node_feature) (vlib_main_t * vm,
1250                                        vlib_node_runtime_t * node,
1251                                        vlib_frame_t * frame)
1252 {
1253   return ip6_reassembly_inline (vm, node, frame, true /* is_feature */ ,
1254                                 false /* is_custom_app */ );
1255 }
1256
1257 /* *INDENT-OFF* */
1258 VLIB_REGISTER_NODE (ip6_reass_node_feature) = {
1259     .name = "ip6-reassembly-feature",
1260     .vector_size = sizeof (u32),
1261     .format_trace = format_ip6_reass_trace,
1262     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1263     .error_strings = ip6_reassembly_error_strings,
1264     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1265     .next_nodes =
1266         {
1267                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1268                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1269                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1270                 [IP6_REASSEMBLY_NEXT_HANDOFF] = "ip6-reass-feature-hoff",
1271         },
1272 };
1273 /* *INDENT-ON* */
1274
1275 /* *INDENT-OFF* */
1276 VNET_FEATURE_INIT (ip6_reassembly_feature, static) = {
1277     .arc_name = "ip6-unicast",
1278     .node_name = "ip6-reassembly-feature",
1279     .runs_before = VNET_FEATURES ("ip6-lookup",
1280                                   "ipsec6-input-feature"),
1281     .runs_after = 0,
1282 };
1283 /* *INDENT-ON* */
1284
1285 #ifndef CLIB_MARCH_VARIANT
1286 static u32
1287 ip6_reass_get_nbuckets ()
1288 {
1289   ip6_reass_main_t *rm = &ip6_reass_main;
1290   u32 nbuckets;
1291   u8 i;
1292
1293   nbuckets = (u32) (rm->max_reass_n / IP6_REASS_HT_LOAD_FACTOR);
1294
1295   for (i = 0; i < 31; i++)
1296     if ((1 << i) >= nbuckets)
1297       break;
1298   nbuckets = 1 << i;
1299
1300   return nbuckets;
1301 }
1302 #endif /* CLIB_MARCH_VARIANT */
1303
1304 typedef enum
1305 {
1306   IP6_EVENT_CONFIG_CHANGED = 1,
1307 } ip6_reass_event_t;
1308
1309 #ifndef CLIB_MARCH_VARIANT
1310 typedef struct
1311 {
1312   int failure;
1313   clib_bihash_48_8_t *new_hash;
1314 } ip6_rehash_cb_ctx;
1315
1316 static void
1317 ip6_rehash_cb (clib_bihash_kv_48_8_t * kv, void *_ctx)
1318 {
1319   ip6_rehash_cb_ctx *ctx = _ctx;
1320   if (clib_bihash_add_del_48_8 (ctx->new_hash, kv, 1))
1321     {
1322       ctx->failure = 1;
1323     }
1324 }
1325
1326 static void
1327 ip6_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1328                       u32 max_reassembly_length, u32 expire_walk_interval_ms)
1329 {
1330   ip6_reass_main.timeout_ms = timeout_ms;
1331   ip6_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1332   ip6_reass_main.max_reass_n = max_reassemblies;
1333   ip6_reass_main.max_reass_len = max_reassembly_length;
1334   ip6_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1335 }
1336
1337 vnet_api_error_t
1338 ip6_reass_set (u32 timeout_ms, u32 max_reassemblies,
1339                u32 max_reassembly_length, u32 expire_walk_interval_ms)
1340 {
1341   u32 old_nbuckets = ip6_reass_get_nbuckets ();
1342   ip6_reass_set_params (timeout_ms, max_reassemblies, max_reassembly_length,
1343                         expire_walk_interval_ms);
1344   vlib_process_signal_event (ip6_reass_main.vlib_main,
1345                              ip6_reass_main.ip6_reass_expire_node_idx,
1346                              IP6_EVENT_CONFIG_CHANGED, 0);
1347   u32 new_nbuckets = ip6_reass_get_nbuckets ();
1348   if (ip6_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1349     {
1350       clib_bihash_48_8_t new_hash;
1351       clib_memset (&new_hash, 0, sizeof (new_hash));
1352       ip6_rehash_cb_ctx ctx;
1353       ctx.failure = 0;
1354       ctx.new_hash = &new_hash;
1355       clib_bihash_init_48_8 (&new_hash, "ip6-reass", new_nbuckets,
1356                              new_nbuckets * 1024);
1357       clib_bihash_foreach_key_value_pair_48_8 (&ip6_reass_main.hash,
1358                                                ip6_rehash_cb, &ctx);
1359       if (ctx.failure)
1360         {
1361           clib_bihash_free_48_8 (&new_hash);
1362           return -1;
1363         }
1364       else
1365         {
1366           clib_bihash_free_48_8 (&ip6_reass_main.hash);
1367           clib_memcpy_fast (&ip6_reass_main.hash, &new_hash,
1368                             sizeof (ip6_reass_main.hash));
1369           clib_bihash_copied (&ip6_reass_main.hash, &new_hash);
1370         }
1371     }
1372   return 0;
1373 }
1374
1375 vnet_api_error_t
1376 ip6_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1377                u32 * expire_walk_interval_ms)
1378 {
1379   *timeout_ms = ip6_reass_main.timeout_ms;
1380   *max_reassemblies = ip6_reass_main.max_reass_n;
1381   *expire_walk_interval_ms = ip6_reass_main.expire_walk_interval_ms;
1382   return 0;
1383 }
1384
1385 static clib_error_t *
1386 ip6_reass_init_function (vlib_main_t * vm)
1387 {
1388   ip6_reass_main_t *rm = &ip6_reass_main;
1389   clib_error_t *error = 0;
1390   u32 nbuckets;
1391   vlib_node_t *node;
1392
1393   rm->vlib_main = vm;
1394
1395   vec_validate (rm->per_thread_data, vlib_num_workers ());
1396   ip6_reass_per_thread_t *rt;
1397   vec_foreach (rt, rm->per_thread_data)
1398   {
1399     clib_spinlock_init (&rt->lock);
1400     pool_alloc (rt->pool, rm->max_reass_n);
1401   }
1402
1403   node = vlib_get_node_by_name (vm, (u8 *) "ip6-reassembly-expire-walk");
1404   ASSERT (node);
1405   rm->ip6_reass_expire_node_idx = node->index;
1406
1407   ip6_reass_set_params (IP6_REASS_TIMEOUT_DEFAULT_MS,
1408                         IP6_REASS_MAX_REASSEMBLIES_DEFAULT,
1409                         IP6_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT,
1410                         IP6_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1411
1412   nbuckets = ip6_reass_get_nbuckets ();
1413   clib_bihash_init_48_8 (&rm->hash, "ip6-reass", nbuckets, nbuckets * 1024);
1414
1415   node = vlib_get_node_by_name (vm, (u8 *) "ip6-drop");
1416   ASSERT (node);
1417   rm->ip6_drop_idx = node->index;
1418   node = vlib_get_node_by_name (vm, (u8 *) "ip6-icmp-error");
1419   ASSERT (node);
1420   rm->ip6_icmp_error_idx = node->index;
1421
1422   if ((error = vlib_call_init_function (vm, ip_main_init)))
1423     return error;
1424   ip6_register_protocol (IP_PROTOCOL_IPV6_FRAGMENTATION,
1425                          ip6_reass_node.index);
1426
1427   rm->fq_index = vlib_frame_queue_main_init (ip6_reass_node.index, 0);
1428   rm->fq_feature_index =
1429     vlib_frame_queue_main_init (ip6_reass_node_feature.index, 0);
1430
1431   return error;
1432 }
1433
1434 VLIB_INIT_FUNCTION (ip6_reass_init_function);
1435 #endif /* CLIB_MARCH_VARIANT */
1436
1437 static uword
1438 ip6_reass_walk_expired (vlib_main_t * vm,
1439                         vlib_node_runtime_t * node, vlib_frame_t * f)
1440 {
1441   ip6_reass_main_t *rm = &ip6_reass_main;
1442   uword event_type, *event_data = 0;
1443
1444   while (true)
1445     {
1446       vlib_process_wait_for_event_or_clock (vm,
1447                                             (f64) rm->expire_walk_interval_ms
1448                                             / (f64) MSEC_PER_SEC);
1449       event_type = vlib_process_get_events (vm, &event_data);
1450
1451       switch (event_type)
1452         {
1453         case ~0:                /* no events => timeout */
1454           /* nothing to do here */
1455           break;
1456         case IP6_EVENT_CONFIG_CHANGED:
1457           break;
1458         default:
1459           clib_warning ("BUG: event type 0x%wx", event_type);
1460           break;
1461         }
1462       f64 now = vlib_time_now (vm);
1463
1464       ip6_reass_t *reass;
1465       int *pool_indexes_to_free = NULL;
1466
1467       uword thread_index = 0;
1468       int index;
1469       const uword nthreads = vlib_num_workers () + 1;
1470       u32 *vec_icmp_bi = NULL;
1471       for (thread_index = 0; thread_index < nthreads; ++thread_index)
1472         {
1473           ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1474           clib_spinlock_lock (&rt->lock);
1475
1476           vec_reset_length (pool_indexes_to_free);
1477           /* *INDENT-OFF* */
1478           pool_foreach_index (index, rt->pool, ({
1479                                 reass = pool_elt_at_index (rt->pool, index);
1480                                 if (now > reass->last_heard + rm->timeout)
1481                                   {
1482                                     vec_add1 (pool_indexes_to_free, index);
1483                                   }
1484                               }));
1485           /* *INDENT-ON* */
1486           int *i;
1487           /* *INDENT-OFF* */
1488           vec_foreach (i, pool_indexes_to_free)
1489           {
1490             ip6_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1491             u32 icmp_bi = ~0;
1492             ip6_reass_on_timeout (vm, node, rm, reass, &icmp_bi);
1493             if (~0 != icmp_bi)
1494               vec_add1 (vec_icmp_bi, icmp_bi);
1495
1496             ip6_reass_free (rm, rt, reass);
1497           }
1498           /* *INDENT-ON* */
1499
1500           clib_spinlock_unlock (&rt->lock);
1501         }
1502
1503       while (vec_len (vec_icmp_bi) > 0)
1504         {
1505           vlib_frame_t *f =
1506             vlib_get_frame_to_node (vm, rm->ip6_icmp_error_idx);
1507           u32 *to_next = vlib_frame_vector_args (f);
1508           u32 n_left_to_next = VLIB_FRAME_SIZE - f->n_vectors;
1509           int trace_frame = 0;
1510           while (vec_len (vec_icmp_bi) > 0 && n_left_to_next > 0)
1511             {
1512               u32 bi = vec_pop (vec_icmp_bi);
1513               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1514               if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1515                 trace_frame = 1;
1516               b->error = node->errors[IP6_ERROR_REASS_TIMEOUT];
1517               to_next[0] = bi;
1518               ++f->n_vectors;
1519               to_next += 1;
1520               n_left_to_next -= 1;
1521             }
1522           f->frame_flags |= (trace_frame * VLIB_FRAME_TRACE);
1523           vlib_put_frame_to_node (vm, rm->ip6_icmp_error_idx, f);
1524         }
1525
1526       vec_free (pool_indexes_to_free);
1527       vec_free (vec_icmp_bi);
1528       if (event_data)
1529         {
1530           _vec_len (event_data) = 0;
1531         }
1532     }
1533
1534   return 0;
1535 }
1536
1537 /* *INDENT-OFF* */
1538 VLIB_REGISTER_NODE (ip6_reass_expire_node, static) = {
1539     .function = ip6_reass_walk_expired,
1540     .format_trace = format_ip6_reass_trace,
1541     .type = VLIB_NODE_TYPE_PROCESS,
1542     .name = "ip6-reassembly-expire-walk",
1543
1544     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1545     .error_strings = ip6_reassembly_error_strings,
1546
1547 };
1548 /* *INDENT-ON* */
1549
1550 static u8 *
1551 format_ip6_reass_key (u8 * s, va_list * args)
1552 {
1553   ip6_reass_key_t *key = va_arg (*args, ip6_reass_key_t *);
1554   s = format (s, "xx_id: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1555               key->xx_id, format_ip6_address, &key->src, format_ip6_address,
1556               &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1557   return s;
1558 }
1559
1560 static u8 *
1561 format_ip6_reass (u8 * s, va_list * args)
1562 {
1563   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1564   ip6_reass_t *reass = va_arg (*args, ip6_reass_t *);
1565
1566   s = format (s, "ID: %lu, key: %U\n  first_bi: %u, data_len: %u, "
1567               "last_packet_octet: %u, trace_op_counter: %u\n",
1568               reass->id, format_ip6_reass_key, &reass->key, reass->first_bi,
1569               reass->data_len, reass->last_packet_octet,
1570               reass->trace_op_counter);
1571   u32 bi = reass->first_bi;
1572   u32 counter = 0;
1573   while (~0 != bi)
1574     {
1575       vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1576       vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1577       s = format (s, "  #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1578                   "fragment[%u, %u]\n",
1579                   counter, vnb->ip.reass.range_first,
1580                   vnb->ip.reass.range_last, bi,
1581                   ip6_reass_buffer_get_data_offset (b),
1582                   ip6_reass_buffer_get_data_len (b),
1583                   vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1584       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1585         {
1586           bi = b->next_buffer;
1587         }
1588       else
1589         {
1590           bi = ~0;
1591         }
1592     }
1593   return s;
1594 }
1595
1596 static clib_error_t *
1597 show_ip6_reass (vlib_main_t * vm, unformat_input_t * input,
1598                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1599 {
1600   ip6_reass_main_t *rm = &ip6_reass_main;
1601
1602   vlib_cli_output (vm, "---------------------");
1603   vlib_cli_output (vm, "IP6 reassembly status");
1604   vlib_cli_output (vm, "---------------------");
1605   bool details = false;
1606   if (unformat (input, "details"))
1607     {
1608       details = true;
1609     }
1610
1611   u32 sum_reass_n = 0;
1612   u64 sum_buffers_n = 0;
1613   ip6_reass_t *reass;
1614   uword thread_index;
1615   const uword nthreads = vlib_num_workers () + 1;
1616   for (thread_index = 0; thread_index < nthreads; ++thread_index)
1617     {
1618       ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1619       clib_spinlock_lock (&rt->lock);
1620       if (details)
1621         {
1622           /* *INDENT-OFF* */
1623           pool_foreach (reass, rt->pool, {
1624             vlib_cli_output (vm, "%U", format_ip6_reass, vm, reass);
1625           });
1626           /* *INDENT-ON* */
1627         }
1628       sum_reass_n += rt->reass_n;
1629       clib_spinlock_unlock (&rt->lock);
1630     }
1631   vlib_cli_output (vm, "---------------------");
1632   vlib_cli_output (vm, "Current IP6 reassemblies count: %lu\n",
1633                    (long unsigned) sum_reass_n);
1634   vlib_cli_output (vm, "Maximum configured concurrent IP6 reassemblies per "
1635                    "worker-thread: %lu\n", (long unsigned) rm->max_reass_n);
1636   vlib_cli_output (vm, "Buffers in use: %lu\n",
1637                    (long unsigned) sum_buffers_n);
1638   return 0;
1639 }
1640
1641 /* *INDENT-OFF* */
1642 VLIB_CLI_COMMAND (show_ip6_reassembly_cmd, static) = {
1643     .path = "show ip6-reassembly",
1644     .short_help = "show ip6-reassembly [details]",
1645     .function = show_ip6_reass,
1646 };
1647 /* *INDENT-ON* */
1648
1649 #ifndef CLIB_MARCH_VARIANT
1650 vnet_api_error_t
1651 ip6_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1652 {
1653   return vnet_feature_enable_disable ("ip6-unicast", "ip6-reassembly-feature",
1654                                       sw_if_index, enable_disable, 0, 0);
1655 }
1656 #endif /* CLIB_MARCH_VARIANT */
1657
1658 #define foreach_ip6_reassembly_handoff_error                       \
1659 _(CONGESTION_DROP, "congestion drop")
1660
1661
1662 typedef enum
1663 {
1664 #define _(sym,str) IP6_REASSEMBLY_HANDOFF_ERROR_##sym,
1665   foreach_ip6_reassembly_handoff_error
1666 #undef _
1667     IP6_REASSEMBLY_HANDOFF_N_ERROR,
1668 } ip6_reassembly_handoff_error_t;
1669
1670 static char *ip6_reassembly_handoff_error_strings[] = {
1671 #define _(sym,string) string,
1672   foreach_ip6_reassembly_handoff_error
1673 #undef _
1674 };
1675
1676 typedef struct
1677 {
1678   u32 next_worker_index;
1679 } ip6_reassembly_handoff_trace_t;
1680
1681 static u8 *
1682 format_ip6_reassembly_handoff_trace (u8 * s, va_list * args)
1683 {
1684   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1685   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1686   ip6_reassembly_handoff_trace_t *t =
1687     va_arg (*args, ip6_reassembly_handoff_trace_t *);
1688
1689   s =
1690     format (s, "ip6-reassembly-handoff: next-worker %d",
1691             t->next_worker_index);
1692
1693   return s;
1694 }
1695
1696 always_inline uword
1697 ip6_reassembly_handoff_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1698                                vlib_frame_t * frame, bool is_feature)
1699 {
1700   ip6_reass_main_t *rm = &ip6_reass_main;
1701
1702   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1703   u32 n_enq, n_left_from, *from;
1704   u16 thread_indices[VLIB_FRAME_SIZE], *ti;
1705   u32 fq_index;
1706
1707   from = vlib_frame_vector_args (frame);
1708   n_left_from = frame->n_vectors;
1709   vlib_get_buffers (vm, from, bufs, n_left_from);
1710
1711   b = bufs;
1712   ti = thread_indices;
1713
1714   fq_index = (is_feature) ? rm->fq_feature_index : rm->fq_index;
1715
1716   while (n_left_from > 0)
1717     {
1718       ti[0] =
1719         (is_feature) ? vnet_buffer (b[0])->ip.
1720         reass.owner_feature_thread_index : vnet_buffer (b[0])->ip.
1721         reass.owner_thread_index;
1722
1723       if (PREDICT_FALSE
1724           ((node->flags & VLIB_NODE_FLAG_TRACE)
1725            && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
1726         {
1727           ip6_reassembly_handoff_trace_t *t =
1728             vlib_add_trace (vm, node, b[0], sizeof (*t));
1729           t->next_worker_index = ti[0];
1730         }
1731
1732       n_left_from -= 1;
1733       ti += 1;
1734       b += 1;
1735     }
1736   n_enq =
1737     vlib_buffer_enqueue_to_thread (vm, fq_index, from, thread_indices,
1738                                    frame->n_vectors, 1);
1739
1740   if (n_enq < frame->n_vectors)
1741     vlib_node_increment_counter (vm, node->node_index,
1742                                  IP6_REASSEMBLY_HANDOFF_ERROR_CONGESTION_DROP,
1743                                  frame->n_vectors - n_enq);
1744   return frame->n_vectors;
1745 }
1746
1747 VLIB_NODE_FN (ip6_reassembly_handoff_node) (vlib_main_t * vm,
1748                                             vlib_node_runtime_t * node,
1749                                             vlib_frame_t * frame)
1750 {
1751   return ip6_reassembly_handoff_inline (vm, node, frame,
1752                                         false /* is_feature */ );
1753 }
1754
1755 /* *INDENT-OFF* */
1756 VLIB_REGISTER_NODE (ip6_reassembly_handoff_node) = {
1757   .name = "ip6-reassembly-handoff",
1758   .vector_size = sizeof (u32),
1759   .n_errors = ARRAY_LEN(ip6_reassembly_handoff_error_strings),
1760   .error_strings = ip6_reassembly_handoff_error_strings,
1761   .format_trace = format_ip6_reassembly_handoff_trace,
1762
1763   .n_next_nodes = 1,
1764
1765   .next_nodes = {
1766     [0] = "error-drop",
1767   },
1768 };
1769
1770
1771 VLIB_NODE_FN (ip6_reassembly_feature_handoff_node) (vlib_main_t * vm,
1772                                vlib_node_runtime_t * node, vlib_frame_t * frame)
1773 {
1774   return ip6_reassembly_handoff_inline (vm, node, frame, true /* is_feature */ );
1775 }
1776
1777
1778 /* *INDENT-OFF* */
1779 VLIB_REGISTER_NODE (ip6_reassembly_feature_handoff_node) = {
1780   .name = "ip6-reass-feature-hoff",
1781   .vector_size = sizeof (u32),
1782   .n_errors = ARRAY_LEN(ip6_reassembly_handoff_error_strings),
1783   .error_strings = ip6_reassembly_handoff_error_strings,
1784   .format_trace = format_ip6_reassembly_handoff_trace,
1785
1786   .n_next_nodes = 1,
1787
1788   .next_nodes = {
1789     [0] = "error-drop",
1790   },
1791 };
1792 /* *INDENT-ON* */
1793
1794 /*
1795  * fd.io coding-style-patch-verification: ON
1796  *
1797  * Local Variables:
1798  * eval: (c-set-style "gnu")
1799  * End:
1800  */