src/vnet/ip/reass/ip4_full_reass.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 IPv4 Full Reassembly.
  19  *
  20  * This file contains the source code for IPv4 full reassembly.
  21  */
  22
  23 #include <vppinfra/vec.h>
  24 #include <vnet/vnet.h>
  25 #include <vnet/ip/ip.h>
  26 #include <vnet/ip/ip.api_enum.h>
  27 #include <vppinfra/fifo.h>
  28 #include <vppinfra/bihash_16_8.h>
  29 #include <vnet/ip/reass/ip4_full_reass.h>
  30 #include <stddef.h>
  31
  32 #define MSEC_PER_SEC 1000
  33 #define IP4_REASS_TIMEOUT_DEFAULT_MS 200
  34
  35 /* As there are only 1024 reass context per thread, either the DDOS attacks
  36  * or fractions of real timeouts, would consume these contexts quickly and
  37  * running out context space and unable to perform reassembly */
  38 #define IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS 50 // 50 ms default
  39 #define IP4_REASS_MAX_REASSEMBLIES_DEFAULT 1024
  40 #define IP4_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT   3
  41 #define IP4_REASS_HT_LOAD_FACTOR (0.75)
  42
  43 #define IP4_REASS_DEBUG_BUFFERS 0
  44 #if IP4_REASS_DEBUG_BUFFERS
  45 #define IP4_REASS_DEBUG_BUFFER(bi, what)             \
  46   do                                                 \
  47     {                                                \
  48       u32 _bi = bi;                                  \
  49       printf (#what "buffer %u", _bi);               \
  50       vlib_buffer_t *_b = vlib_get_buffer (vm, _bi); \
  51       while (_b->flags & VLIB_BUFFER_NEXT_PRESENT)   \
  52         {                                            \
  53           _bi = _b->next_buffer;                     \
  54           printf ("[%u]", _bi);                      \
  55           _b = vlib_get_buffer (vm, _bi);            \
  56         }                                            \
  57       printf ("\n");                                 \
  58       fflush (stdout);                               \
  59     }                                                \
  60   while (0)
  61 #else
  62 #define IP4_REASS_DEBUG_BUFFER(...)
  63 #endif
  64
  65 typedef enum
  66 {
  67   IP4_REASS_RC_OK,
  68   IP4_REASS_RC_TOO_MANY_FRAGMENTS,
  69   IP4_REASS_RC_INTERNAL_ERROR,
  70   IP4_REASS_RC_NO_BUF,
  71   IP4_REASS_RC_HANDOFF,
  72 } ip4_full_reass_rc_t;
  73
  74 typedef struct
  75 {
  76   struct
  77   {
  78     u16 frag_id;
  79     u8 proto;
  80     u8 unused;
  81     u32 fib_index;
  82     ip4_address_t src;
  83     ip4_address_t dst;
  84   };
  85 } ip4_full_reass_key_t;
  86
  87 STATIC_ASSERT_SIZEOF (ip4_full_reass_key_t, 16);
  88
  89 typedef union
  90 {
  91   struct
  92   {
  93     u32 reass_index;
  94     u32 memory_owner_thread_index;
  95   };
  96   u64 as_u64;
  97 } ip4_full_reass_val_t;
  98
  99 typedef union
 100 {
 101   struct
 102   {
 103     ip4_full_reass_key_t k;
 104     ip4_full_reass_val_t v;
 105   };
 106   clib_bihash_kv_16_8_t kv;
 107 } ip4_full_reass_kv_t;
 108
 109 always_inline u32
 110 ip4_full_reass_buffer_get_data_offset (vlib_buffer_t * b)
 111 {
 112   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 113   return vnb->ip.reass.range_first - vnb->ip.reass.fragment_first;
 114 }
 115
 116 always_inline u16
 117 ip4_full_reass_buffer_get_data_len (vlib_buffer_t * b)
 118 {
 119   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 120   return clib_min (vnb->ip.reass.range_last, vnb->ip.reass.fragment_last) -
 121     (vnb->ip.reass.fragment_first +
 122      ip4_full_reass_buffer_get_data_offset (b)) + 1;
 123 }
 124
 125 typedef struct
 126 {
 127   // hash table key
 128   ip4_full_reass_key_t key;
 129   // time when last packet was received
 130   f64 last_heard;
 131   // internal id of this reassembly
 132   u64 id;
 133   // buffer index of first buffer in this reassembly context
 134   u32 first_bi;
 135   // last octet of packet, ~0 until fragment without more_fragments arrives
 136   u32 last_packet_octet;
 137   // length of data collected so far
 138   u32 data_len;
 139   // trace operation counter
 140   u32 trace_op_counter;
 141   // next index - used by non-feature node
 142   u32 next_index;
 143   // error next index - used by custom apps (~0 if not used)
 144   u32 error_next_index;
 145   // minimum fragment length for this reassembly - used to estimate MTU
 146   u16 min_fragment_length;
 147   // number of fragments in this reassembly
 148   u32 fragments_n;
 149   // thread owning memory for this context (whose pool contains this ctx)
 150   u32 memory_owner_thread_index;
 151   // thread which received fragment with offset 0 and which sends out the
 152   // completed reassembly
 153   u32 sendout_thread_index;
 154 } ip4_full_reass_t;
 155
 156 typedef struct
 157 {
 158   ip4_full_reass_t *pool;
 159   u32 reass_n;
 160   u32 id_counter;
 161   // for pacing the main thread timeouts
 162   u32 last_id;
 163   clib_spinlock_t lock;
 164 } ip4_full_reass_per_thread_t;
 165
 166 typedef struct
 167 {
 168   // IPv4 config
 169   u32 timeout_ms;
 170   f64 timeout;
 171   u32 expire_walk_interval_ms;
 172   // maximum number of fragments in one reassembly
 173   u32 max_reass_len;
 174   // maximum number of reassemblies
 175   u32 max_reass_n;
 176
 177   // IPv4 runtime
 178   clib_bihash_16_8_t hash;
 179   // per-thread data
 180   ip4_full_reass_per_thread_t *per_thread_data;
 181
 182   // convenience
 183   vlib_main_t *vlib_main;
 184
 185   u32 ip4_full_reass_expire_node_idx;
 186
 187   /** Worker handoff */
 188   u32 fq_index;
 189   u32 fq_local_index;
 190   u32 fq_feature_index;
 191   u32 fq_custom_index;
 192
 193   // reference count for enabling/disabling feature - per interface
 194   u32 *feature_use_refcount_per_intf;
 195
 196   // whether local fragmented packets are reassembled or not
 197   int is_local_reass_enabled;
 198 } ip4_full_reass_main_t;
 199
 200 extern ip4_full_reass_main_t ip4_full_reass_main;
 201
 202 #ifndef CLIB_MARCH_VARIANT
 203 ip4_full_reass_main_t ip4_full_reass_main;
 204 #endif /* CLIB_MARCH_VARIANT */
 205
 206 typedef enum
 207 {
 208   IP4_FULL_REASS_NEXT_INPUT,
 209   IP4_FULL_REASS_NEXT_DROP,
 210   IP4_FULL_REASS_NEXT_HANDOFF,
 211   IP4_FULL_REASS_N_NEXT,
 212 } ip4_full_reass_next_t;
 213
 214 typedef enum
 215 {
 216   NORMAL,
 217   FEATURE,
 218   CUSTOM
 219 } ip4_full_reass_node_type_t;
 220
 221 typedef enum
 222 {
 223   RANGE_NEW,
 224   RANGE_SHRINK,
 225   RANGE_DISCARD,
 226   RANGE_OVERLAP,
 227   FINALIZE,
 228   HANDOFF,
 229   PASSTHROUGH,
 230 } ip4_full_reass_trace_operation_e;
 231
 232 typedef struct
 233 {
 234   u16 range_first;
 235   u16 range_last;
 236   u32 range_bi;
 237   i32 data_offset;
 238   u32 data_len;
 239   u32 first_bi;
 240 } ip4_full_reass_range_trace_t;
 241
 242 typedef struct
 243 {
 244   ip4_full_reass_trace_operation_e action;
 245   u32 reass_id;
 246   ip4_full_reass_range_trace_t trace_range;
 247   u32 size_diff;
 248   u32 op_id;
 249   u32 thread_id;
 250   u32 thread_id_to;
 251   u32 fragment_first;
 252   u32 fragment_last;
 253   u32 total_data_len;
 254   bool is_after_handoff;
 255   ip4_header_t ip4_header;
 256 } ip4_full_reass_trace_t;
 257
 258 extern vlib_node_registration_t ip4_full_reass_node;
 259 extern vlib_node_registration_t ip4_full_reass_node_feature;
 260 extern vlib_node_registration_t ip4_full_reass_node_custom;
 261
 262 static void
 263 ip4_full_reass_trace_details (vlib_main_t * vm, u32 bi,
 264                               ip4_full_reass_range_trace_t * trace)
 265 {
 266   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 267   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 268   trace->range_first = vnb->ip.reass.range_first;
 269   trace->range_last = vnb->ip.reass.range_last;
 270   trace->data_offset = ip4_full_reass_buffer_get_data_offset (b);
 271   trace->data_len = ip4_full_reass_buffer_get_data_len (b);
 272   trace->range_bi = bi;
 273 }
 274
 275 static u8 *
 276 format_ip4_full_reass_range_trace (u8 * s, va_list * args)
 277 {
 278   ip4_full_reass_range_trace_t *trace =
 279     va_arg (*args, ip4_full_reass_range_trace_t *);
 280   s =
 281     format (s, "range: [%u, %u], off %d, len %u, bi %u", trace->range_first,
 282             trace->range_last, trace->data_offset, trace->data_len,
 283             trace->range_bi);
 284   return s;
 285 }
 286
 287 static u8 *
 288 format_ip4_full_reass_trace (u8 * s, va_list * args)
 289 {
 290   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
 291   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
 292   ip4_full_reass_trace_t *t = va_arg (*args, ip4_full_reass_trace_t *);
 293   u32 indent = 0;
 294   if (~0 != t->reass_id)
 295     {
 296       if (t->is_after_handoff)
 297         {
 298           s =
 299             format (s, "%U\n", format_ip4_header, &t->ip4_header,
 300                     sizeof (t->ip4_header));
 301           indent = 2;
 302         }
 303       s =
 304         format (s, "%Ureass id: %u, op id: %u, ", format_white_space, indent,
 305                 t->reass_id, t->op_id);
 306       indent = format_get_indent (s);
 307       s =
 308         format (s,
 309                 "first bi: %u, data len: %u, ip/fragment[%u, %u]",
 310                 t->trace_range.first_bi, t->total_data_len, t->fragment_first,
 311                 t->fragment_last);
 312     }
 313   switch (t->action)
 314     {
 315     case RANGE_SHRINK:
 316       s = format (s, "\n%Ushrink %U by %u", format_white_space, indent,
 317                   format_ip4_full_reass_range_trace, &t->trace_range,
 318                   t->size_diff);
 319       break;
 320     case RANGE_DISCARD:
 321       s = format (s, "\n%Udiscard %U", format_white_space, indent,
 322                   format_ip4_full_reass_range_trace, &t->trace_range);
 323       break;
 324     case RANGE_NEW:
 325       s = format (s, "\n%Unew %U", format_white_space, indent,
 326                   format_ip4_full_reass_range_trace, &t->trace_range);
 327       break;
 328     case RANGE_OVERLAP:
 329       s = format (s, "\n%Uoverlapping/ignored %U", format_white_space, indent,
 330                   format_ip4_full_reass_range_trace, &t->trace_range);
 331       break;
 332     case FINALIZE:
 333       s = format (s, "\n%Ufinalize reassembly", format_white_space, indent);
 334       break;
 335     case HANDOFF:
 336       s =
 337         format (s, "handoff from thread #%u to thread #%u", t->thread_id,
 338                 t->thread_id_to);
 339       break;
 340     case PASSTHROUGH:
 341       s = format (s, "passthrough - not a fragment");
 342       break;
 343     }
 344   return s;
 345 }
 346
 347 static void
 348 ip4_full_reass_add_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
 349                           ip4_full_reass_t * reass, u32 bi,
 350                           ip4_full_reass_trace_operation_e action,
 351                           u32 size_diff, u32 thread_id_to)
 352 {
 353   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 354   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 355   if (pool_is_free_index
 356       (vm->trace_main.trace_buffer_pool, vlib_buffer_get_trace_index (b)))
 357     {
 358       // this buffer's trace is gone
 359       b->flags &= ~VLIB_BUFFER_IS_TRACED;
 360       return;
 361     }
 362   bool is_after_handoff = false;
 363   if (vlib_buffer_get_trace_thread (b) != vm->thread_index)
 364     {
 365       is_after_handoff = true;
 366     }
 367   ip4_full_reass_trace_t *t = vlib_add_trace (vm, node, b, sizeof (t[0]));
 368   t->is_after_handoff = is_after_handoff;
 369   if (t->is_after_handoff)
 370     {
 371       clib_memcpy (&t->ip4_header, vlib_buffer_get_current (b),
 372                    clib_min (sizeof (t->ip4_header), b->current_length));
 373     }
 374   if (reass)
 375     {
 376       t->reass_id = reass->id;
 377       t->op_id = reass->trace_op_counter;
 378       t->trace_range.first_bi = reass->first_bi;
 379       t->total_data_len = reass->data_len;
 380       ++reass->trace_op_counter;
 381     }
 382   else
 383     {
 384       t->reass_id = ~0;
 385       t->op_id = 0;
 386       t->trace_range.first_bi = 0;
 387       t->total_data_len = 0;
 388     }
 389   t->action = action;
 390   ip4_full_reass_trace_details (vm, bi, &t->trace_range);
 391   t->size_diff = size_diff;
 392   t->thread_id = vm->thread_index;
 393   t->thread_id_to = thread_id_to;
 394   t->fragment_first = vnb->ip.reass.fragment_first;
 395   t->fragment_last = vnb->ip.reass.fragment_last;
 396 #if 0
 397   static u8 *s = NULL;
 398   s = format (s, "%U", format_ip4_full_reass_trace, NULL, NULL, t);
 399   printf ("%.*s\n", vec_len (s), s);
 400   fflush (stdout);
 401   vec_reset_length (s);
 402 #endif
 403 }
 404
 405 always_inline void
 406 ip4_full_reass_free_ctx (ip4_full_reass_per_thread_t * rt,
 407                          ip4_full_reass_t * reass)
 408 {
 409   pool_put (rt->pool, reass);
 410   --rt->reass_n;
 411 }
 412
 413 always_inline void
 414 ip4_full_reass_free (ip4_full_reass_main_t * rm,
 415                      ip4_full_reass_per_thread_t * rt,
 416                      ip4_full_reass_t * reass)
 417 {
 418   clib_bihash_kv_16_8_t kv = {};
 419   clib_memcpy_fast (&kv, &reass->key, sizeof (kv.key));
 420   clib_bihash_add_del_16_8 (&rm->hash, &kv, 0);
 421   return ip4_full_reass_free_ctx (rt, reass);
 422 }
 423
 424 /* n_left_to_next, and to_next are taken as input params, as this function
 425  * could be called from a graphnode, where its managing local copy of these
 426  * variables, and ignoring those and still trying to enqueue the buffers
 427  * with local variables would cause either buffer leak or corruption */
 428 always_inline void
 429 ip4_full_reass_drop_all (vlib_main_t *vm, vlib_node_runtime_t *node,
 430                          ip4_full_reass_t *reass)
 431 {
 432   u32 range_bi = reass->first_bi;
 433   vlib_buffer_t *range_b;
 434   vnet_buffer_opaque_t *range_vnb;
 435   u32 *to_free = NULL;
 436
 437   while (~0 != range_bi)
 438     {
 439       range_b = vlib_get_buffer (vm, range_bi);
 440       range_vnb = vnet_buffer (range_b);
 441
 442       if (~0 != range_bi)
 443         {
 444           vec_add1 (to_free, range_bi);
 445         }
 446
 447       range_bi = range_vnb->ip.reass.next_range_bi;
 448     }
 449
 450   /* send to next_error_index */
 451   if (~0 != reass->error_next_index &&
 452       reass->error_next_index < node->n_next_nodes)
 453     {
 454       u32 n_free = vec_len (to_free);
 455
 456       /* record number of packets sent to custom app */
 457       vlib_node_increment_counter (vm, node->node_index,
 458                                    IP4_ERROR_REASS_TO_CUSTOM_APP, n_free);
 459
 460       if (node->flags & VLIB_NODE_FLAG_TRACE)
 461         for (u32 i = 0; i < n_free; i++)
 462           {
 463             vlib_buffer_t *b = vlib_get_buffer (vm, to_free[i]);
 464             if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
 465               ip4_full_reass_add_trace (vm, node, reass, to_free[i],
 466                                         RANGE_DISCARD, 0, ~0);
 467           }
 468
 469       vlib_buffer_enqueue_to_single_next (vm, node, to_free,
 470                                           reass->error_next_index, n_free);
 471     }
 472   else
 473     {
 474       vlib_buffer_free (vm, to_free, vec_len (to_free));
 475     }
 476   vec_free (to_free);
 477 }
 478
 479 always_inline void
 480 sanitize_reass_buffers_add_missing (vlib_main_t *vm, ip4_full_reass_t *reass,
 481                                     u32 *bi0)
 482 {
 483   u32 range_bi = reass->first_bi;
 484   vlib_buffer_t *range_b;
 485   vnet_buffer_opaque_t *range_vnb;
 486
 487   while (~0 != range_bi)
 488     {
 489       range_b = vlib_get_buffer (vm, range_bi);
 490       range_vnb = vnet_buffer (range_b);
 491       u32 bi = range_bi;
 492       if (~0 != bi)
 493         {
 494           if (bi == *bi0)
 495             *bi0 = ~0;
 496           if (range_b->flags & VLIB_BUFFER_NEXT_PRESENT)
 497             {
 498               u32 _bi = bi;
 499               vlib_buffer_t *_b = vlib_get_buffer (vm, _bi);
 500               while (_b->flags & VLIB_BUFFER_NEXT_PRESENT)
 501                 {
 502                   if (_b->next_buffer != range_vnb->ip.reass.next_range_bi)
 503                     {
 504                       _bi = _b->next_buffer;
 505                       _b = vlib_get_buffer (vm, _bi);
 506                     }
 507                   else
 508                     {
 509                       _b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 510                       break;
 511                     }
 512                 }
 513             }
 514           range_bi = range_vnb->ip.reass.next_range_bi;
 515         }
 516     }
 517   if (*bi0 != ~0)
 518     {
 519       vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
 520       vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
 521       if (~0 != reass->first_bi)
 522         {
 523           fvnb->ip.reass.next_range_bi = reass->first_bi;
 524           reass->first_bi = *bi0;
 525         }
 526       else
 527         {
 528           reass->first_bi = *bi0;
 529           fvnb->ip.reass.next_range_bi = ~0;
 530         }
 531       *bi0 = ~0;
 532     }
 533 }
 534
 535 always_inline void
 536 ip4_full_reass_init (ip4_full_reass_t * reass)
 537 {
 538   reass->first_bi = ~0;
 539   reass->last_packet_octet = ~0;
 540   reass->data_len = 0;
 541   reass->next_index = ~0;
 542   reass->error_next_index = ~0;
 543 }
 544
 545 always_inline ip4_full_reass_t *
 546 ip4_full_reass_find_or_create (vlib_main_t *vm, vlib_node_runtime_t *node,
 547                                ip4_full_reass_main_t *rm,
 548                                ip4_full_reass_per_thread_t *rt,
 549                                ip4_full_reass_kv_t *kv, u8 *do_handoff)
 550 {
 551   ip4_full_reass_t *reass;
 552   f64 now;
 553
 554 again:
 555
 556   reass = NULL;
 557   now = vlib_time_now (vm);
 558   if (!clib_bihash_search_16_8 (&rm->hash, &kv->kv, &kv->kv))
 559     {
 560       if (vm->thread_index != kv->v.memory_owner_thread_index)
 561         {
 562           *do_handoff = 1;
 563           return NULL;
 564         }
 565       reass =
 566         pool_elt_at_index (rm->per_thread_data
 567                            [kv->v.memory_owner_thread_index].pool,
 568                            kv->v.reass_index);
 569
 570       if (now > reass->last_heard + rm->timeout)
 571         {
 572           vlib_node_increment_counter (vm, node->node_index,
 573                                        IP4_ERROR_REASS_TIMEOUT, 1);
 574           ip4_full_reass_drop_all (vm, node, reass);
 575           ip4_full_reass_free (rm, rt, reass);
 576           reass = NULL;
 577         }
 578     }
 579
 580   if (reass)
 581     {
 582       reass->last_heard = now;
 583       return reass;
 584     }
 585
 586   if (rt->reass_n >= rm->max_reass_n)
 587     {
 588       reass = NULL;
 589       return reass;
 590     }
 591   else
 592     {
 593       pool_get (rt->pool, reass);
 594       clib_memset (reass, 0, sizeof (*reass));
 595       reass->id = ((u64) vm->thread_index * 1000000000) + rt->id_counter;
 596       reass->memory_owner_thread_index = vm->thread_index;
 597       ++rt->id_counter;
 598       ip4_full_reass_init (reass);
 599       ++rt->reass_n;
 600     }
 601
 602   clib_memcpy_fast (&reass->key, &kv->kv.key, sizeof (reass->key));
 603   kv->v.reass_index = (reass - rt->pool);
 604   kv->v.memory_owner_thread_index = vm->thread_index;
 605   reass->last_heard = now;
 606
 607   int rv = clib_bihash_add_del_16_8 (&rm->hash, &kv->kv, 2);
 608   if (rv)
 609     {
 610       ip4_full_reass_free_ctx (rt, reass);
 611       reass = NULL;
 612       // if other worker created a context already work with the other copy
 613       if (-2 == rv)
 614         goto again;
 615     }
 616
 617   return reass;
 618 }
 619
 620 always_inline ip4_full_reass_rc_t
 621 ip4_full_reass_finalize (vlib_main_t * vm, vlib_node_runtime_t * node,
 622                          ip4_full_reass_main_t * rm,
 623                          ip4_full_reass_per_thread_t * rt,
 624                          ip4_full_reass_t * reass, u32 * bi0,
 625                          u32 * next0, u32 * error0, bool is_custom)
 626 {
 627   vlib_buffer_t *first_b = vlib_get_buffer (vm, reass->first_bi);
 628   vlib_buffer_t *last_b = NULL;
 629   u32 sub_chain_bi = reass->first_bi;
 630   u32 total_length = 0;
 631   do
 632     {
 633       u32 tmp_bi = sub_chain_bi;
 634       vlib_buffer_t *tmp = vlib_get_buffer (vm, tmp_bi);
 635       ip4_header_t *ip = vlib_buffer_get_current (tmp);
 636       vnet_buffer_opaque_t *vnb = vnet_buffer (tmp);
 637       if (!(vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first) &&
 638           !(vnb->ip.reass.range_last > vnb->ip.reass.fragment_first))
 639         {
 640           return IP4_REASS_RC_INTERNAL_ERROR;
 641         }
 642
 643       u32 data_len = ip4_full_reass_buffer_get_data_len (tmp);
 644       u32 trim_front =
 645         ip4_header_bytes (ip) + ip4_full_reass_buffer_get_data_offset (tmp);
 646       u32 trim_end =
 647         vlib_buffer_length_in_chain (vm, tmp) - trim_front - data_len;
 648       if (tmp_bi == reass->first_bi)
 649         {
 650           /* first buffer - keep ip4 header */
 651           if (0 != ip4_full_reass_buffer_get_data_offset (tmp))
 652             {
 653               return IP4_REASS_RC_INTERNAL_ERROR;
 654             }
 655           trim_front = 0;
 656           trim_end = vlib_buffer_length_in_chain (vm, tmp) - data_len -
 657             ip4_header_bytes (ip);
 658           if (!(vlib_buffer_length_in_chain (vm, tmp) - trim_end > 0))
 659             {
 660               return IP4_REASS_RC_INTERNAL_ERROR;
 661             }
 662         }
 663       u32 keep_data =
 664         vlib_buffer_length_in_chain (vm, tmp) - trim_front - trim_end;
 665       while (1)
 666         {
 667           if (trim_front)
 668             {
 669               if (trim_front > tmp->current_length)
 670                 {
 671                   /* drop whole buffer */
 672                   u32 to_be_freed_bi = tmp_bi;
 673                   trim_front -= tmp->current_length;
 674                   if (!(tmp->flags & VLIB_BUFFER_NEXT_PRESENT))
 675                     {
 676                       return IP4_REASS_RC_INTERNAL_ERROR;
 677                     }
 678                   tmp->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 679                   tmp_bi = tmp->next_buffer;
 680                   tmp->next_buffer = 0;
 681                   tmp = vlib_get_buffer (vm, tmp_bi);
 682                   vlib_buffer_free_one (vm, to_be_freed_bi);
 683                   continue;
 684                 }
 685               else
 686                 {
 687                   vlib_buffer_advance (tmp, trim_front);
 688                   trim_front = 0;
 689                 }
 690             }
 691           if (keep_data)
 692             {
 693               if (last_b)
 694                 {
 695                   last_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
 696                   last_b->next_buffer = tmp_bi;
 697                 }
 698               last_b = tmp;
 699               if (keep_data <= tmp->current_length)
 700                 {
 701                   tmp->current_length = keep_data;
 702                   keep_data = 0;
 703                 }
 704               else
 705                 {
 706                   keep_data -= tmp->current_length;
 707                   if (!(tmp->flags & VLIB_BUFFER_NEXT_PRESENT))
 708                     {
 709                       return IP4_REASS_RC_INTERNAL_ERROR;
 710                     }
 711                 }
 712               total_length += tmp->current_length;
 713               if (tmp->flags & VLIB_BUFFER_NEXT_PRESENT)
 714                 {
 715                   tmp_bi = tmp->next_buffer;
 716                   tmp = vlib_get_buffer (vm, tmp->next_buffer);
 717                 }
 718               else
 719                 {
 720                   break;
 721                 }
 722             }
 723           else
 724             {
 725               u32 to_be_freed_bi = tmp_bi;
 726               if (reass->first_bi == tmp_bi)
 727                 {
 728                   return IP4_REASS_RC_INTERNAL_ERROR;
 729                 }
 730               if (tmp->flags & VLIB_BUFFER_NEXT_PRESENT)
 731                 {
 732                   tmp->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 733                   tmp_bi = tmp->next_buffer;
 734                   tmp->next_buffer = 0;
 735                   tmp = vlib_get_buffer (vm, tmp_bi);
 736                   vlib_buffer_free_one (vm, to_be_freed_bi);
 737                 }
 738               else
 739                 {
 740                   tmp->next_buffer = 0;
 741                   vlib_buffer_free_one (vm, to_be_freed_bi);
 742                   break;
 743                 }
 744             }
 745         }
 746       sub_chain_bi =
 747         vnet_buffer (vlib_get_buffer (vm, sub_chain_bi))->ip.
 748         reass.next_range_bi;
 749     }
 750   while (~0 != sub_chain_bi);
 751
 752   if (!last_b)
 753     {
 754       return IP4_REASS_RC_INTERNAL_ERROR;
 755     }
 756   last_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 757
 758   if (total_length < first_b->current_length)
 759     {
 760       return IP4_REASS_RC_INTERNAL_ERROR;
 761     }
 762   total_length -= first_b->current_length;
 763   first_b->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
 764   first_b->total_length_not_including_first_buffer = total_length;
 765   ip4_header_t *ip = vlib_buffer_get_current (first_b);
 766   ip->flags_and_fragment_offset = 0;
 767   ip->length = clib_host_to_net_u16 (first_b->current_length + total_length);
 768   ip->checksum = ip4_header_checksum (ip);
 769   if (!vlib_buffer_chain_linearize (vm, first_b))
 770     {
 771       return IP4_REASS_RC_NO_BUF;
 772     }
 773   // reset to reconstruct the mbuf linking
 774   first_b->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
 775   if (PREDICT_FALSE (first_b->flags & VLIB_BUFFER_IS_TRACED))
 776     {
 777       ip4_full_reass_add_trace (vm, node, reass, reass->first_bi, FINALIZE, 0,
 778                                 ~0);
 779 #if 0
 780       // following code does a hexdump of packet fragments to stdout ...
 781       do
 782         {
 783           u32 bi = reass->first_bi;
 784           u8 *s = NULL;
 785           while (~0 != bi)
 786             {
 787               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 788               s = format (s, "%u: %U\n", bi, format_hexdump,
 789                           vlib_buffer_get_current (b), b->current_length);
 790               if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 791                 {
 792                   bi = b->next_buffer;
 793                 }
 794               else
 795                 {
 796                   break;
 797                 }
 798             }
 799           printf ("%.*s\n", vec_len (s), s);
 800           fflush (stdout);
 801           vec_free (s);
 802         }
 803       while (0);
 804 #endif
 805     }
 806   *bi0 = reass->first_bi;
 807   if (!is_custom)
 808     {
 809       *next0 = IP4_FULL_REASS_NEXT_INPUT;
 810     }
 811   else
 812     {
 813       *next0 = reass->next_index;
 814     }
 815   vnet_buffer (first_b)->ip.reass.estimated_mtu = reass->min_fragment_length;
 816
 817   /* Keep track of number of successfully reassembled packets and number of
 818    * fragments reassembled */
 819   vlib_node_increment_counter (vm, node->node_index, IP4_ERROR_REASS_SUCCESS,
 820                                1);
 821
 822   vlib_node_increment_counter (vm, node->node_index,
 823                                IP4_ERROR_REASS_FRAGMENTS_REASSEMBLED,
 824                                reass->fragments_n);
 825
 826   *error0 = IP4_ERROR_NONE;
 827   ip4_full_reass_free (rm, rt, reass);
 828   reass = NULL;
 829   return IP4_REASS_RC_OK;
 830 }
 831
 832 always_inline ip4_full_reass_rc_t
 833 ip4_full_reass_insert_range_in_chain (vlib_main_t * vm,
 834                                       ip4_full_reass_t * reass,
 835                                       u32 prev_range_bi, u32 new_next_bi)
 836 {
 837   vlib_buffer_t *new_next_b = vlib_get_buffer (vm, new_next_bi);
 838   vnet_buffer_opaque_t *new_next_vnb = vnet_buffer (new_next_b);
 839   if (~0 != prev_range_bi)
 840     {
 841       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
 842       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
 843       new_next_vnb->ip.reass.next_range_bi = prev_vnb->ip.reass.next_range_bi;
 844       prev_vnb->ip.reass.next_range_bi = new_next_bi;
 845     }
 846   else
 847     {
 848       if (~0 != reass->first_bi)
 849         {
 850           new_next_vnb->ip.reass.next_range_bi = reass->first_bi;
 851         }
 852       reass->first_bi = new_next_bi;
 853     }
 854   vnet_buffer_opaque_t *vnb = vnet_buffer (new_next_b);
 855   if (!(vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first) &&
 856       !(vnb->ip.reass.range_last > vnb->ip.reass.fragment_first))
 857     {
 858       return IP4_REASS_RC_INTERNAL_ERROR;
 859     }
 860   reass->data_len += ip4_full_reass_buffer_get_data_len (new_next_b);
 861   return IP4_REASS_RC_OK;
 862 }
 863
 864 always_inline ip4_full_reass_rc_t
 865 ip4_full_reass_remove_range_from_chain (vlib_main_t * vm,
 866                                         vlib_node_runtime_t * node,
 867                                         ip4_full_reass_t * reass,
 868                                         u32 prev_range_bi, u32 discard_bi)
 869 {
 870   vlib_buffer_t *discard_b = vlib_get_buffer (vm, discard_bi);
 871   vnet_buffer_opaque_t *discard_vnb = vnet_buffer (discard_b);
 872   if (~0 != prev_range_bi)
 873     {
 874       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
 875       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
 876       if (!(prev_vnb->ip.reass.next_range_bi == discard_bi))
 877         {
 878           return IP4_REASS_RC_INTERNAL_ERROR;
 879         }
 880       prev_vnb->ip.reass.next_range_bi = discard_vnb->ip.reass.next_range_bi;
 881     }
 882   else
 883     {
 884       reass->first_bi = discard_vnb->ip.reass.next_range_bi;
 885     }
 886   vnet_buffer_opaque_t *vnb = vnet_buffer (discard_b);
 887   if (!(vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first) &&
 888       !(vnb->ip.reass.range_last > vnb->ip.reass.fragment_first))
 889     {
 890       return IP4_REASS_RC_INTERNAL_ERROR;
 891     }
 892   reass->data_len -= ip4_full_reass_buffer_get_data_len (discard_b);
 893   while (1)
 894     {
 895       u32 to_be_freed_bi = discard_bi;
 896       if (PREDICT_FALSE (discard_b->flags & VLIB_BUFFER_IS_TRACED))
 897         {
 898           ip4_full_reass_add_trace (vm, node, reass, discard_bi, RANGE_DISCARD,
 899                                     0, ~0);
 900         }
 901       if (discard_b->flags & VLIB_BUFFER_NEXT_PRESENT)
 902         {
 903           discard_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 904           discard_bi = discard_b->next_buffer;
 905           discard_b->next_buffer = 0;
 906           discard_b = vlib_get_buffer (vm, discard_bi);
 907           vlib_buffer_free_one (vm, to_be_freed_bi);
 908         }
 909       else
 910         {
 911           discard_b->next_buffer = 0;
 912           vlib_buffer_free_one (vm, to_be_freed_bi);
 913           break;
 914         }
 915     }
 916   return IP4_REASS_RC_OK;
 917 }
 918
 919 always_inline ip4_full_reass_rc_t
 920 ip4_full_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
 921                        ip4_full_reass_main_t * rm,
 922                        ip4_full_reass_per_thread_t * rt,
 923                        ip4_full_reass_t * reass, u32 * bi0, u32 * next0,
 924                        u32 * error0, bool is_custom, u32 * handoff_thread_idx)
 925 {
 926   vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
 927   vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
 928   if (is_custom)
 929     {
 930       // store (error_)next_index before it's overwritten
 931       reass->next_index = fvnb->ip.reass.next_index;
 932       reass->error_next_index = fvnb->ip.reass.error_next_index;
 933     }
 934   ip4_full_reass_rc_t rc = IP4_REASS_RC_OK;
 935   int consumed = 0;
 936   ip4_header_t *fip = vlib_buffer_get_current (fb);
 937   const u32 fragment_first = ip4_get_fragment_offset_bytes (fip);
 938   const u32 fragment_length =
 939     clib_net_to_host_u16 (fip->length) - ip4_header_bytes (fip);
 940   const u32 fragment_last = fragment_first + fragment_length - 1;
 941   fvnb->ip.reass.fragment_first = fragment_first;
 942   fvnb->ip.reass.fragment_last = fragment_last;
 943   int more_fragments = ip4_get_fragment_more (fip);
 944   u32 candidate_range_bi = reass->first_bi;
 945   u32 prev_range_bi = ~0;
 946   fvnb->ip.reass.range_first = fragment_first;
 947   fvnb->ip.reass.range_last = fragment_last;
 948   fvnb->ip.reass.next_range_bi = ~0;
 949   if (!more_fragments)
 950     {
 951       reass->last_packet_octet = fragment_last;
 952     }
 953   if (~0 == reass->first_bi)
 954     {
 955       // starting a new reassembly
 956       rc =
 957         ip4_full_reass_insert_range_in_chain (vm, reass, prev_range_bi, *bi0);
 958       if (IP4_REASS_RC_OK != rc)
 959         {
 960           return rc;
 961         }
 962       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 963         {
 964           ip4_full_reass_add_trace (vm, node, reass, *bi0, RANGE_NEW, 0, ~0);
 965         }
 966       *bi0 = ~0;
 967       reass->min_fragment_length = clib_net_to_host_u16 (fip->length);
 968       reass->fragments_n = 1;
 969       return IP4_REASS_RC_OK;
 970     }
 971   reass->min_fragment_length =
 972     clib_min (clib_net_to_host_u16 (fip->length),
 973               fvnb->ip.reass.estimated_mtu);
 974   while (~0 != candidate_range_bi)
 975     {
 976       vlib_buffer_t *candidate_b = vlib_get_buffer (vm, candidate_range_bi);
 977       vnet_buffer_opaque_t *candidate_vnb = vnet_buffer (candidate_b);
 978       if (fragment_first > candidate_vnb->ip.reass.range_last)
 979         {
 980           // this fragments starts after candidate range
 981           prev_range_bi = candidate_range_bi;
 982           candidate_range_bi = candidate_vnb->ip.reass.next_range_bi;
 983           if (candidate_vnb->ip.reass.range_last < fragment_last &&
 984               ~0 == candidate_range_bi)
 985             {
 986               // special case - this fragment falls beyond all known ranges
 987               rc = ip4_full_reass_insert_range_in_chain (vm, reass,
 988                                                          prev_range_bi, *bi0);
 989               if (IP4_REASS_RC_OK != rc)
 990                 {
 991                   return rc;
 992                 }
 993               consumed = 1;
 994               break;
 995             }
 996           continue;
 997         }
 998       if (fragment_last < candidate_vnb->ip.reass.range_first)
 999         {
1000           // this fragment ends before candidate range without any overlap
1001           rc = ip4_full_reass_insert_range_in_chain (vm, reass, prev_range_bi,
1002                                                      *bi0);
1003           if (IP4_REASS_RC_OK != rc)
1004             {
1005               return rc;
1006             }
1007           consumed = 1;
1008         }
1009       else
1010         {
1011           if (fragment_first >= candidate_vnb->ip.reass.range_first &&
1012               fragment_last <= candidate_vnb->ip.reass.range_last)
1013             {
1014               // this fragment is a (sub)part of existing range, ignore it
1015               if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
1016                 {
1017                   ip4_full_reass_add_trace (vm, node, reass, *bi0,
1018                                             RANGE_OVERLAP, 0, ~0);
1019                 }
1020               break;
1021             }
1022           int discard_candidate = 0;
1023           if (fragment_first < candidate_vnb->ip.reass.range_first)
1024             {
1025               u32 overlap =
1026                 fragment_last - candidate_vnb->ip.reass.range_first + 1;
1027               if (overlap < ip4_full_reass_buffer_get_data_len (candidate_b))
1028                 {
1029                   candidate_vnb->ip.reass.range_first += overlap;
1030                   if (reass->data_len < overlap)
1031                     {
1032                       return IP4_REASS_RC_INTERNAL_ERROR;
1033                     }
1034                   reass->data_len -= overlap;
1035                   if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
1036                     {
1037                       ip4_full_reass_add_trace (vm, node, reass,
1038                                                 candidate_range_bi,
1039                                                 RANGE_SHRINK, 0, ~0);
1040                     }
1041                   rc = ip4_full_reass_insert_range_in_chain (
1042                     vm, reass, prev_range_bi, *bi0);
1043                   if (IP4_REASS_RC_OK != rc)
1044                     {
1045                       return rc;
1046                     }
1047                   consumed = 1;
1048                 }
1049               else
1050                 {
1051                   discard_candidate = 1;
1052                 }
1053             }
1054           else if (fragment_last > candidate_vnb->ip.reass.range_last)
1055             {
1056               u32 overlap =
1057                 candidate_vnb->ip.reass.range_last - fragment_first + 1;
1058               if (overlap < ip4_full_reass_buffer_get_data_len (candidate_b))
1059                 {
1060                   fvnb->ip.reass.range_first += overlap;
1061                   if (~0 != candidate_vnb->ip.reass.next_range_bi)
1062                     {
1063                       prev_range_bi = candidate_range_bi;
1064                       candidate_range_bi =
1065                         candidate_vnb->ip.reass.next_range_bi;
1066                       continue;
1067                     }
1068                   else
1069                     {
1070                       // special case - last range discarded
1071                       rc = ip4_full_reass_insert_range_in_chain (
1072                         vm, reass, candidate_range_bi, *bi0);
1073                       if (IP4_REASS_RC_OK != rc)
1074                         {
1075                           return rc;
1076                         }
1077                       consumed = 1;
1078                     }
1079                 }
1080               else
1081                 {
1082                   discard_candidate = 1;
1083                 }
1084             }
1085           else
1086             {
1087               discard_candidate = 1;
1088             }
1089           if (discard_candidate)
1090             {
1091               u32 next_range_bi = candidate_vnb->ip.reass.next_range_bi;
1092               // discard candidate range, probe next range
1093               rc = ip4_full_reass_remove_range_from_chain (
1094                 vm, node, reass, prev_range_bi, candidate_range_bi);
1095               if (IP4_REASS_RC_OK != rc)
1096                 {
1097                   return rc;
1098                 }
1099               if (~0 != next_range_bi)
1100                 {
1101                   candidate_range_bi = next_range_bi;
1102                   continue;
1103                 }
1104               else
1105                 {
1106                   // special case - last range discarded
1107                   rc = ip4_full_reass_insert_range_in_chain (
1108                     vm, reass, prev_range_bi, *bi0);
1109                   if (IP4_REASS_RC_OK != rc)
1110                     {
1111                       return rc;
1112                     }
1113                   consumed = 1;
1114                 }
1115             }
1116         }
1117       break;
1118     }
1119   ++reass->fragments_n;
1120   if (consumed)
1121     {
1122       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
1123         {
1124           ip4_full_reass_add_trace (vm, node, reass, *bi0, RANGE_NEW, 0, ~0);
1125         }
1126     }
1127   if (~0 != reass->last_packet_octet &&
1128       reass->data_len == reass->last_packet_octet + 1)
1129     {
1130       *handoff_thread_idx = reass->sendout_thread_index;
1131       int handoff =
1132         reass->memory_owner_thread_index != reass->sendout_thread_index;
1133       rc =
1134         ip4_full_reass_finalize (vm, node, rm, rt, reass, bi0, next0, error0,
1135                                  is_custom);
1136       if (IP4_REASS_RC_OK == rc && handoff)
1137         {
1138           rc = IP4_REASS_RC_HANDOFF;
1139         }
1140     }
1141   else
1142     {
1143       if (consumed)
1144         {
1145           *bi0 = ~0;
1146           if (reass->fragments_n > rm->max_reass_len)
1147             {
1148               rc = IP4_REASS_RC_TOO_MANY_FRAGMENTS;
1149             }
1150         }
1151       else
1152         {
1153           *next0 = IP4_FULL_REASS_NEXT_DROP;
1154           *error0 = IP4_ERROR_REASS_DUPLICATE_FRAGMENT;
1155         }
1156     }
1157   return rc;
1158 }
1159
1160 always_inline uword
1161 ip4_full_reass_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1162                        vlib_frame_t *frame, ip4_full_reass_node_type_t type,
1163                        bool is_local)
1164 {
1165   u32 *from = vlib_frame_vector_args (frame);
1166   u32 n_left_from, n_left_to_next, *to_next, next_index;
1167   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1168   ip4_full_reass_per_thread_t *rt = &rm->per_thread_data[vm->thread_index];
1169   clib_spinlock_lock (&rt->lock);
1170
1171   n_left_from = frame->n_vectors;
1172   next_index = node->cached_next_index;
1173   while (n_left_from > 0)
1174     {
1175       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1176
1177       while (n_left_from > 0 && n_left_to_next > 0)
1178         {
1179           u32 bi0;
1180           vlib_buffer_t *b0;
1181           u32 next0;
1182           u32 error0 = IP4_ERROR_NONE;
1183
1184           bi0 = from[0];
1185           b0 = vlib_get_buffer (vm, bi0);
1186
1187           ip4_header_t *ip0 = vlib_buffer_get_current (b0);
1188           if (!ip4_get_fragment_more (ip0) && !ip4_get_fragment_offset (ip0))
1189             {
1190               // this is a whole packet - no fragmentation
1191               if (CUSTOM != type)
1192                 {
1193                   next0 = IP4_FULL_REASS_NEXT_INPUT;
1194                 }
1195               else
1196                 {
1197                   next0 = vnet_buffer (b0)->ip.reass.next_index;
1198                 }
1199               ip4_full_reass_add_trace (vm, node, NULL, bi0, PASSTHROUGH, 0,
1200                                         ~0);
1201               goto packet_enqueue;
1202             }
1203
1204           if (is_local && !rm->is_local_reass_enabled)
1205             {
1206               next0 = IP4_FULL_REASS_NEXT_DROP;
1207               goto packet_enqueue;
1208             }
1209
1210           const u32 fragment_first = ip4_get_fragment_offset_bytes (ip0);
1211           const u32 fragment_length =
1212             clib_net_to_host_u16 (ip0->length) - ip4_header_bytes (ip0);
1213           const u32 fragment_last = fragment_first + fragment_length - 1;
1214
1215           /* Keep track of received fragments */
1216           vlib_node_increment_counter (vm, node->node_index,
1217                                        IP4_ERROR_REASS_FRAGMENTS_RCVD, 1);
1218
1219           if (fragment_first > fragment_last ||
1220               fragment_first + fragment_length > UINT16_MAX - 20 ||
1221               (fragment_length < 8 && // 8 is minimum frag length per RFC 791
1222                ip4_get_fragment_more (ip0)))
1223             {
1224               next0 = IP4_FULL_REASS_NEXT_DROP;
1225               error0 = IP4_ERROR_REASS_MALFORMED_PACKET;
1226               goto packet_enqueue;
1227             }
1228
1229           u32 fib_index = vec_elt (ip4_main.fib_index_by_sw_if_index,
1230                                    vnet_buffer (b0)->sw_if_index[VLIB_RX]);
1231
1232           ip4_full_reass_kv_t kv = { .k.fib_index = fib_index,
1233                                      .k.src.as_u32 = ip0->src_address.as_u32,
1234                                      .k.dst.as_u32 = ip0->dst_address.as_u32,
1235                                      .k.frag_id = ip0->fragment_id,
1236                                      .k.proto = ip0->protocol
1237
1238           };
1239           u8 do_handoff = 0;
1240
1241           ip4_full_reass_t *reass =
1242             ip4_full_reass_find_or_create (vm, node, rm, rt, &kv, &do_handoff);
1243
1244           if (reass)
1245             {
1246               const u32 fragment_first = ip4_get_fragment_offset_bytes (ip0);
1247               if (0 == fragment_first)
1248                 {
1249                   reass->sendout_thread_index = vm->thread_index;
1250                 }
1251             }
1252
1253           if (PREDICT_FALSE (do_handoff))
1254             {
1255               next0 = IP4_FULL_REASS_NEXT_HANDOFF;
1256               vnet_buffer (b0)->ip.reass.owner_thread_index =
1257                 kv.v.memory_owner_thread_index;
1258             }
1259           else if (reass)
1260             {
1261               u32 handoff_thread_idx;
1262               u32 counter = ~0;
1263               switch (ip4_full_reass_update
1264                       (vm, node, rm, rt, reass, &bi0, &next0,
1265                        &error0, CUSTOM == type, &handoff_thread_idx))
1266                 {
1267                 case IP4_REASS_RC_OK:
1268                   /* nothing to do here */
1269                   break;
1270                 case IP4_REASS_RC_HANDOFF:
1271                   next0 = IP4_FULL_REASS_NEXT_HANDOFF;
1272                   b0 = vlib_get_buffer (vm, bi0);
1273                   vnet_buffer (b0)->ip.reass.owner_thread_index =
1274                     handoff_thread_idx;
1275                   break;
1276                 case IP4_REASS_RC_TOO_MANY_FRAGMENTS:
1277                   counter = IP4_ERROR_REASS_FRAGMENT_CHAIN_TOO_LONG;
1278                   break;
1279                 case IP4_REASS_RC_NO_BUF:
1280                   counter = IP4_ERROR_REASS_NO_BUF;
1281                   break;
1282                 case IP4_REASS_RC_INTERNAL_ERROR:
1283                   counter = IP4_ERROR_REASS_INTERNAL_ERROR;
1284                   /* Sanitization is needed in internal error cases only, as
1285                    * the incoming packet is already dropped in other cases,
1286                    * also adding bi0 back to the reassembly list, fixes the
1287                    * leaking of buffers during internal errors.
1288                    *
1289                    * Also it doesnt make sense to send these buffers custom
1290                    * app, these fragments are with internal errors */
1291                   sanitize_reass_buffers_add_missing (vm, reass, &bi0);
1292                   reass->error_next_index = ~0;
1293                   break;
1294                 }
1295
1296               if (~0 != counter)
1297                 {
1298                   vlib_node_increment_counter (vm, node->node_index, counter,
1299                                                1);
1300                   ip4_full_reass_drop_all (vm, node, reass);
1301                   ip4_full_reass_free (rm, rt, reass);
1302                   goto next_packet;
1303                 }
1304             }
1305           else
1306             {
1307               next0 = IP4_FULL_REASS_NEXT_DROP;
1308               error0 = IP4_ERROR_REASS_LIMIT_REACHED;
1309             }
1310
1311
1312         packet_enqueue:
1313
1314           if (bi0 != ~0)
1315             {
1316               to_next[0] = bi0;
1317               to_next += 1;
1318               n_left_to_next -= 1;
1319
1320               /* bi0 might have been updated by reass_finalize, reload */
1321               b0 = vlib_get_buffer (vm, bi0);
1322               if (IP4_ERROR_NONE != error0)
1323                 {
1324                   b0->error = node->errors[error0];
1325                 }
1326
1327               if (next0 == IP4_FULL_REASS_NEXT_HANDOFF)
1328                 {
1329                   if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
1330                     {
1331                       ip4_full_reass_add_trace (
1332                         vm, node, NULL, bi0, HANDOFF, 0,
1333                         vnet_buffer (b0)->ip.reass.owner_thread_index);
1334                     }
1335                 }
1336               else if (FEATURE == type && IP4_ERROR_NONE == error0)
1337                 {
1338                   vnet_feature_next (&next0, b0);
1339                 }
1340
1341               /* Increment the counter to-custom-app also as this fragment is
1342                * also going to application */
1343               if (CUSTOM == type)
1344                 {
1345                   vlib_node_increment_counter (
1346                     vm, node->node_index, IP4_ERROR_REASS_TO_CUSTOM_APP, 1);
1347                 }
1348
1349               vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1350                                                to_next, n_left_to_next,
1351                                                bi0, next0);
1352               IP4_REASS_DEBUG_BUFFER (bi0, enqueue_next);
1353             }
1354
1355         next_packet:
1356           from += 1;
1357           n_left_from -= 1;
1358         }
1359
1360       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1361     }
1362
1363   clib_spinlock_unlock (&rt->lock);
1364   return frame->n_vectors;
1365 }
1366
1367 VLIB_NODE_FN (ip4_full_reass_node) (vlib_main_t * vm,
1368                                     vlib_node_runtime_t * node,
1369                                     vlib_frame_t * frame)
1370 {
1371   return ip4_full_reass_inline (vm, node, frame, NORMAL, false /* is_local */);
1372 }
1373
1374 VLIB_REGISTER_NODE (ip4_full_reass_node) = {
1375     .name = "ip4-full-reassembly",
1376     .vector_size = sizeof (u32),
1377     .format_trace = format_ip4_full_reass_trace,
1378     .n_errors = IP4_N_ERROR,
1379     .error_counters = ip4_error_counters,
1380     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1381     .next_nodes =
1382         {
1383                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1384                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1385                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-full-reassembly-handoff",
1386
1387         },
1388 };
1389
1390 VLIB_NODE_FN (ip4_local_full_reass_node)
1391 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
1392 {
1393   return ip4_full_reass_inline (vm, node, frame, NORMAL, true /* is_local */);
1394 }
1395
1396 VLIB_REGISTER_NODE (ip4_local_full_reass_node) = {
1397     .name = "ip4-local-full-reassembly",
1398     .vector_size = sizeof (u32),
1399     .format_trace = format_ip4_full_reass_trace,
1400     .n_errors = IP4_N_ERROR,
1401     .error_counters = ip4_error_counters,
1402     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1403     .next_nodes =
1404         {
1405                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1406                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1407                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-local-full-reassembly-handoff",
1408
1409         },
1410 };
1411
1412 VLIB_NODE_FN (ip4_full_reass_node_feature) (vlib_main_t * vm,
1413                                             vlib_node_runtime_t * node,
1414                                             vlib_frame_t * frame)
1415 {
1416   return ip4_full_reass_inline (vm, node, frame, FEATURE,
1417                                 false /* is_local */);
1418 }
1419
1420 VLIB_REGISTER_NODE (ip4_full_reass_node_feature) = {
1421     .name = "ip4-full-reassembly-feature",
1422     .vector_size = sizeof (u32),
1423     .format_trace = format_ip4_full_reass_trace,
1424     .n_errors = IP4_N_ERROR,
1425     .error_counters = ip4_error_counters,
1426     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1427     .next_nodes =
1428         {
1429                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1430                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1431                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-full-reass-feature-hoff",
1432         },
1433 };
1434
1435 VNET_FEATURE_INIT (ip4_full_reass_feature, static) = {
1436     .arc_name = "ip4-unicast",
1437     .node_name = "ip4-full-reassembly-feature",
1438     .runs_before = VNET_FEATURES ("ip4-lookup",
1439                                   "ipsec4-input-feature"),
1440     .runs_after = 0,
1441 };
1442
1443 VLIB_NODE_FN (ip4_full_reass_node_custom) (vlib_main_t * vm,
1444                                            vlib_node_runtime_t * node,
1445                                            vlib_frame_t * frame)
1446 {
1447   return ip4_full_reass_inline (vm, node, frame, CUSTOM, false /* is_local */);
1448 }
1449
1450 VLIB_REGISTER_NODE (ip4_full_reass_node_custom) = {
1451     .name = "ip4-full-reassembly-custom",
1452     .vector_size = sizeof (u32),
1453     .format_trace = format_ip4_full_reass_trace,
1454     .n_errors = IP4_N_ERROR,
1455     .error_counters = ip4_error_counters,
1456     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1457     .next_nodes =
1458         {
1459                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1460                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1461                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-full-reass-custom-hoff",
1462         },
1463 };
1464
1465 VNET_FEATURE_INIT (ip4_full_reass_custom, static) = {
1466     .arc_name = "ip4-unicast",
1467     .node_name = "ip4-full-reassembly-feature",
1468     .runs_before = VNET_FEATURES ("ip4-lookup",
1469                                   "ipsec4-input-feature"),
1470     .runs_after = 0,
1471 };
1472
1473
1474 #ifndef CLIB_MARCH_VARIANT
1475 uword
1476 ip4_full_reass_custom_register_next_node (uword node_index)
1477 {
1478   return vlib_node_add_next (vlib_get_main (),
1479                              ip4_full_reass_node_custom.index, node_index);
1480 }
1481
1482 always_inline u32
1483 ip4_full_reass_get_nbuckets ()
1484 {
1485   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1486   u32 nbuckets;
1487   u8 i;
1488
1489   /* need more mem with more workers */
1490   nbuckets = (u32) (rm->max_reass_n * (vlib_num_workers () + 1) /
1491                     IP4_REASS_HT_LOAD_FACTOR);
1492
1493   for (i = 0; i < 31; i++)
1494     if ((1 << i) >= nbuckets)
1495       break;
1496   nbuckets = 1 << i;
1497
1498   return nbuckets;
1499 }
1500 #endif /* CLIB_MARCH_VARIANT */
1501
1502 typedef enum
1503 {
1504   IP4_EVENT_CONFIG_CHANGED = 1,
1505 } ip4_full_reass_event_t;
1506
1507 typedef struct
1508 {
1509   int failure;
1510   clib_bihash_16_8_t *new_hash;
1511 } ip4_rehash_cb_ctx;
1512
1513 #ifndef CLIB_MARCH_VARIANT
1514 static int
1515 ip4_rehash_cb (clib_bihash_kv_16_8_t * kv, void *_ctx)
1516 {
1517   ip4_rehash_cb_ctx *ctx = _ctx;
1518   if (clib_bihash_add_del_16_8 (ctx->new_hash, kv, 1))
1519     {
1520       ctx->failure = 1;
1521     }
1522   return (BIHASH_WALK_CONTINUE);
1523 }
1524
1525 static void
1526 ip4_full_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1527                            u32 max_reassembly_length,
1528                            u32 expire_walk_interval_ms)
1529 {
1530   ip4_full_reass_main.timeout_ms = timeout_ms;
1531   ip4_full_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1532   ip4_full_reass_main.max_reass_n = max_reassemblies;
1533   ip4_full_reass_main.max_reass_len = max_reassembly_length;
1534   ip4_full_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1535 }
1536
1537 vnet_api_error_t
1538 ip4_full_reass_set (u32 timeout_ms, u32 max_reassemblies,
1539                     u32 max_reassembly_length, u32 expire_walk_interval_ms)
1540 {
1541   u32 old_nbuckets = ip4_full_reass_get_nbuckets ();
1542   ip4_full_reass_set_params (timeout_ms, max_reassemblies,
1543                              max_reassembly_length, expire_walk_interval_ms);
1544   vlib_process_signal_event (ip4_full_reass_main.vlib_main,
1545                              ip4_full_reass_main.ip4_full_reass_expire_node_idx,
1546                              IP4_EVENT_CONFIG_CHANGED, 0);
1547   u32 new_nbuckets = ip4_full_reass_get_nbuckets ();
1548   if (ip4_full_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1549     {
1550       clib_bihash_16_8_t new_hash;
1551       clib_memset (&new_hash, 0, sizeof (new_hash));
1552       ip4_rehash_cb_ctx ctx;
1553       ctx.failure = 0;
1554       ctx.new_hash = &new_hash;
1555       clib_bihash_init_16_8 (&new_hash, "ip4-dr", new_nbuckets,
1556                              new_nbuckets * 1024);
1557       clib_bihash_foreach_key_value_pair_16_8 (&ip4_full_reass_main.hash,
1558                                                ip4_rehash_cb, &ctx);
1559       if (ctx.failure)
1560         {
1561           clib_bihash_free_16_8 (&new_hash);
1562           return -1;
1563         }
1564       else
1565         {
1566           clib_bihash_free_16_8 (&ip4_full_reass_main.hash);
1567           clib_memcpy_fast (&ip4_full_reass_main.hash, &new_hash,
1568                             sizeof (ip4_full_reass_main.hash));
1569           clib_bihash_copied (&ip4_full_reass_main.hash, &new_hash);
1570         }
1571     }
1572   return 0;
1573 }
1574
1575 vnet_api_error_t
1576 ip4_full_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1577                     u32 * max_reassembly_length,
1578                     u32 * expire_walk_interval_ms)
1579 {
1580   *timeout_ms = ip4_full_reass_main.timeout_ms;
1581   *max_reassemblies = ip4_full_reass_main.max_reass_n;
1582   *max_reassembly_length = ip4_full_reass_main.max_reass_len;
1583   *expire_walk_interval_ms = ip4_full_reass_main.expire_walk_interval_ms;
1584   return 0;
1585 }
1586
1587 static clib_error_t *
1588 ip4_full_reass_init_function (vlib_main_t * vm)
1589 {
1590   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1591   clib_error_t *error = 0;
1592   u32 nbuckets;
1593   vlib_node_t *node;
1594
1595   rm->vlib_main = vm;
1596
1597   vec_validate (rm->per_thread_data, vlib_num_workers ());
1598   ip4_full_reass_per_thread_t *rt;
1599   vec_foreach (rt, rm->per_thread_data)
1600   {
1601     clib_spinlock_init (&rt->lock);
1602     pool_alloc (rt->pool, rm->max_reass_n);
1603   }
1604
1605   node = vlib_get_node_by_name (vm, (u8 *) "ip4-full-reassembly-expire-walk");
1606   ASSERT (node);
1607   rm->ip4_full_reass_expire_node_idx = node->index;
1608
1609   ip4_full_reass_set_params (IP4_REASS_TIMEOUT_DEFAULT_MS,
1610                              IP4_REASS_MAX_REASSEMBLIES_DEFAULT,
1611                              IP4_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT,
1612                              IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1613
1614   nbuckets = ip4_full_reass_get_nbuckets ();
1615   clib_bihash_init_16_8 (&rm->hash, "ip4-dr", nbuckets, nbuckets * 1024);
1616
1617   rm->fq_index = vlib_frame_queue_main_init (ip4_full_reass_node.index, 0);
1618   rm->fq_local_index =
1619     vlib_frame_queue_main_init (ip4_local_full_reass_node.index, 0);
1620   rm->fq_feature_index =
1621     vlib_frame_queue_main_init (ip4_full_reass_node_feature.index, 0);
1622   rm->fq_custom_index =
1623     vlib_frame_queue_main_init (ip4_full_reass_node_custom.index, 0);
1624
1625   rm->feature_use_refcount_per_intf = NULL;
1626   rm->is_local_reass_enabled = 1;
1627
1628   return error;
1629 }
1630
1631 VLIB_INIT_FUNCTION (ip4_full_reass_init_function);
1632 #endif /* CLIB_MARCH_VARIANT */
1633
1634 static uword
1635 ip4_full_reass_walk_expired (vlib_main_t *vm, vlib_node_runtime_t *node,
1636                              CLIB_UNUSED (vlib_frame_t *f))
1637 {
1638   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1639   uword event_type, *event_data = 0;
1640
1641   while (true)
1642     {
1643       vlib_process_wait_for_event_or_clock (vm,
1644                                             (f64)
1645                                             rm->expire_walk_interval_ms /
1646                                             (f64) MSEC_PER_SEC);
1647       event_type = vlib_process_get_events (vm, &event_data);
1648
1649       switch (event_type)
1650         {
1651         case ~0:
1652           /* no events => timeout */
1653           /* fallthrough */
1654         case IP4_EVENT_CONFIG_CHANGED:
1655           /* nothing to do here */
1656           break;
1657         default:
1658           clib_warning ("BUG: event type 0x%wx", event_type);
1659           break;
1660         }
1661       f64 now = vlib_time_now (vm);
1662
1663       ip4_full_reass_t *reass;
1664       int *pool_indexes_to_free = NULL;
1665
1666       uword thread_index = 0;
1667       int index;
1668       const uword nthreads = vlib_num_workers () + 1;
1669
1670       for (thread_index = 0; thread_index < nthreads; ++thread_index)
1671         {
1672           ip4_full_reass_per_thread_t *rt =
1673             &rm->per_thread_data[thread_index];
1674           clib_spinlock_lock (&rt->lock);
1675
1676           vec_reset_length (pool_indexes_to_free);
1677
1678           /* Pace the number of timeouts handled per thread,to avoid barrier
1679            * sync issues in real world scenarios */
1680
1681           u32 beg = rt->last_id;
1682           /* to ensure we walk at least once per sec per context */
1683           u32 end =
1684             beg + (IP4_REASS_MAX_REASSEMBLIES_DEFAULT *
1685                      IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS / MSEC_PER_SEC +
1686                    1);
1687           if (end > vec_len (rt->pool))
1688             {
1689               end = vec_len (rt->pool);
1690               rt->last_id = 0;
1691             }
1692           else
1693             {
1694               rt->last_id = end;
1695             }
1696
1697           pool_foreach_stepping_index (index, beg, end, rt->pool)
1698           {
1699             reass = pool_elt_at_index (rt->pool, index);
1700             if (now > reass->last_heard + rm->timeout)
1701               {
1702                 vec_add1 (pool_indexes_to_free, index);
1703               }
1704           }
1705
1706           if (vec_len (pool_indexes_to_free))
1707             vlib_node_increment_counter (vm, node->node_index,
1708                                          IP4_ERROR_REASS_TIMEOUT,
1709                                          vec_len (pool_indexes_to_free));
1710           int *i;
1711           vec_foreach (i, pool_indexes_to_free)
1712           {
1713             ip4_full_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1714             ip4_full_reass_drop_all (vm, node, reass);
1715             ip4_full_reass_free (rm, rt, reass);
1716           }
1717
1718           clib_spinlock_unlock (&rt->lock);
1719         }
1720
1721       vec_free (pool_indexes_to_free);
1722       if (event_data)
1723         {
1724           vec_set_len (event_data, 0);
1725         }
1726     }
1727
1728   return 0;
1729 }
1730
1731 VLIB_REGISTER_NODE (ip4_full_reass_expire_node) = {
1732   .function = ip4_full_reass_walk_expired,
1733   .type = VLIB_NODE_TYPE_PROCESS,
1734   .name = "ip4-full-reassembly-expire-walk",
1735   .format_trace = format_ip4_full_reass_trace,
1736   .n_errors = IP4_N_ERROR,
1737   .error_counters = ip4_error_counters,
1738 };
1739
1740 static u8 *
1741 format_ip4_full_reass_key (u8 * s, va_list * args)
1742 {
1743   ip4_full_reass_key_t *key = va_arg (*args, ip4_full_reass_key_t *);
1744   s =
1745     format (s, "fib_index: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1746             key->fib_index, format_ip4_address, &key->src, format_ip4_address,
1747             &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1748   return s;
1749 }
1750
1751 static u8 *
1752 format_ip4_reass (u8 * s, va_list * args)
1753 {
1754   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1755   ip4_full_reass_t *reass = va_arg (*args, ip4_full_reass_t *);
1756
1757   s = format (s, "ID: %lu, key: %U\n  first_bi: %u, data_len: %u, "
1758               "last_packet_octet: %u, trace_op_counter: %u\n",
1759               reass->id, format_ip4_full_reass_key, &reass->key,
1760               reass->first_bi, reass->data_len,
1761               reass->last_packet_octet, reass->trace_op_counter);
1762
1763   u32 bi = reass->first_bi;
1764   u32 counter = 0;
1765   while (~0 != bi)
1766     {
1767       vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1768       vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1769       s =
1770         format (s,
1771                 "  #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1772                 "fragment[%u, %u]\n", counter, vnb->ip.reass.range_first,
1773                 vnb->ip.reass.range_last, bi,
1774                 ip4_full_reass_buffer_get_data_offset (b),
1775                 ip4_full_reass_buffer_get_data_len (b),
1776                 vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1777       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1778         {
1779           bi = b->next_buffer;
1780         }
1781       else
1782         {
1783           bi = ~0;
1784         }
1785     }
1786   return s;
1787 }
1788
1789 static clib_error_t *
1790 show_ip4_reass (vlib_main_t * vm,
1791                 unformat_input_t * input,
1792                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1793 {
1794   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1795
1796   vlib_cli_output (vm, "---------------------");
1797   vlib_cli_output (vm, "IP4 reassembly status");
1798   vlib_cli_output (vm, "---------------------");
1799   bool details = false;
1800   if (unformat (input, "details"))
1801     {
1802       details = true;
1803     }
1804
1805   u32 sum_reass_n = 0;
1806   ip4_full_reass_t *reass;
1807   uword thread_index;
1808   const uword nthreads = vlib_num_workers () + 1;
1809   for (thread_index = 0; thread_index < nthreads; ++thread_index)
1810     {
1811       ip4_full_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1812       clib_spinlock_lock (&rt->lock);
1813       if (details)
1814         {
1815           pool_foreach (reass, rt->pool) {
1816             vlib_cli_output (vm, "%U", format_ip4_reass, vm, reass);
1817           }
1818         }
1819       sum_reass_n += rt->reass_n;
1820       clib_spinlock_unlock (&rt->lock);
1821     }
1822   vlib_cli_output (vm, "---------------------");
1823   vlib_cli_output (vm, "Current full IP4 reassemblies count: %lu\n",
1824                    (long unsigned) sum_reass_n);
1825   vlib_cli_output (vm,
1826                    "Maximum configured concurrent full IP4 reassemblies per worker-thread: %lu\n",
1827                    (long unsigned) rm->max_reass_n);
1828   vlib_cli_output (vm,
1829                    "Maximum configured amount of fragments "
1830                    "per full IP4 reassembly: %lu\n",
1831                    (long unsigned) rm->max_reass_len);
1832   vlib_cli_output (vm,
1833                    "Maximum configured full IP4 reassembly timeout: %lums\n",
1834                    (long unsigned) rm->timeout_ms);
1835   vlib_cli_output (vm,
1836                    "Maximum configured full IP4 reassembly expire walk interval: %lums\n",
1837                    (long unsigned) rm->expire_walk_interval_ms);
1838   return 0;
1839 }
1840
1841 VLIB_CLI_COMMAND (show_ip4_full_reass_cmd, static) = {
1842     .path = "show ip4-full-reassembly",
1843     .short_help = "show ip4-full-reassembly [details]",
1844     .function = show_ip4_reass,
1845 };
1846
1847 #ifndef CLIB_MARCH_VARIANT
1848 vnet_api_error_t
1849 ip4_full_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1850 {
1851   return vnet_feature_enable_disable ("ip4-unicast",
1852                                       "ip4-full-reassembly-feature",
1853                                       sw_if_index, enable_disable, 0, 0);
1854 }
1855 #endif /* CLIB_MARCH_VARIANT */
1856
1857
1858 #define foreach_ip4_full_reass_handoff_error                       \
1859 _(CONGESTION_DROP, "congestion drop")
1860
1861
1862 typedef enum
1863 {
1864 #define _(sym,str) IP4_FULL_REASS_HANDOFF_ERROR_##sym,
1865   foreach_ip4_full_reass_handoff_error
1866 #undef _
1867     IP4_FULL_REASS_HANDOFF_N_ERROR,
1868 } ip4_full_reass_handoff_error_t;
1869
1870 static char *ip4_full_reass_handoff_error_strings[] = {
1871 #define _(sym,string) string,
1872   foreach_ip4_full_reass_handoff_error
1873 #undef _
1874 };
1875
1876 typedef struct
1877 {
1878   u32 next_worker_index;
1879 } ip4_full_reass_handoff_trace_t;
1880
1881 static u8 *
1882 format_ip4_full_reass_handoff_trace (u8 * s, va_list * args)
1883 {
1884   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1885   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1886   ip4_full_reass_handoff_trace_t *t =
1887     va_arg (*args, ip4_full_reass_handoff_trace_t *);
1888
1889   s =
1890     format (s, "ip4-full-reassembly-handoff: next-worker %d",
1891             t->next_worker_index);
1892
1893   return s;
1894 }
1895
1896 always_inline uword
1897 ip4_full_reass_handoff_node_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1898                                     vlib_frame_t *frame,
1899                                     ip4_full_reass_node_type_t type,
1900                                     bool is_local)
1901 {
1902   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1903
1904   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1905   u32 n_enq, n_left_from, *from;
1906   u16 thread_indices[VLIB_FRAME_SIZE], *ti;
1907   u32 fq_index;
1908
1909   from = vlib_frame_vector_args (frame);
1910   n_left_from = frame->n_vectors;
1911   vlib_get_buffers (vm, from, bufs, n_left_from);
1912
1913   b = bufs;
1914   ti = thread_indices;
1915
1916   switch (type)
1917     {
1918     case NORMAL:
1919       if (is_local)
1920         {
1921           fq_index = rm->fq_local_index;
1922         }
1923       else
1924         {
1925           fq_index = rm->fq_index;
1926         }
1927       break;
1928     case FEATURE:
1929       fq_index = rm->fq_feature_index;
1930       break;
1931     case CUSTOM:
1932       fq_index = rm->fq_custom_index;
1933       break;
1934     default:
1935       clib_warning ("Unexpected `type' (%d)!", type);
1936     }
1937
1938   while (n_left_from > 0)
1939     {
1940       ti[0] = vnet_buffer (b[0])->ip.reass.owner_thread_index;
1941
1942       if (PREDICT_FALSE
1943           ((node->flags & VLIB_NODE_FLAG_TRACE)
1944            && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
1945         {
1946           ip4_full_reass_handoff_trace_t *t =
1947             vlib_add_trace (vm, node, b[0], sizeof (*t));
1948           t->next_worker_index = ti[0];
1949         }
1950
1951       n_left_from -= 1;
1952       ti += 1;
1953       b += 1;
1954     }
1955   n_enq = vlib_buffer_enqueue_to_thread (vm, node, fq_index, from,
1956                                          thread_indices, frame->n_vectors, 1);
1957
1958   if (n_enq < frame->n_vectors)
1959     vlib_node_increment_counter (vm, node->node_index,
1960                                  IP4_FULL_REASS_HANDOFF_ERROR_CONGESTION_DROP,
1961                                  frame->n_vectors - n_enq);
1962   return frame->n_vectors;
1963 }
1964
1965 VLIB_NODE_FN (ip4_full_reass_handoff_node) (vlib_main_t * vm,
1966                                             vlib_node_runtime_t * node,
1967                                             vlib_frame_t * frame)
1968 {
1969   return ip4_full_reass_handoff_node_inline (vm, node, frame, NORMAL,
1970                                              false /* is_local */);
1971 }
1972
1973
1974 VLIB_REGISTER_NODE (ip4_full_reass_handoff_node) = {
1975   .name = "ip4-full-reassembly-handoff",
1976   .vector_size = sizeof (u32),
1977   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
1978   .error_strings = ip4_full_reass_handoff_error_strings,
1979   .format_trace = format_ip4_full_reass_handoff_trace,
1980
1981   .n_next_nodes = 1,
1982
1983   .next_nodes = {
1984     [0] = "error-drop",
1985   },
1986 };
1987
1988 VLIB_NODE_FN (ip4_local_full_reass_handoff_node)
1989 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
1990 {
1991   return ip4_full_reass_handoff_node_inline (vm, node, frame, NORMAL,
1992                                              true /* is_local */);
1993 }
1994
1995 VLIB_REGISTER_NODE (ip4_local_full_reass_handoff_node) = {
1996   .name = "ip4-local-full-reassembly-handoff",
1997   .vector_size = sizeof (u32),
1998   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
1999   .error_strings = ip4_full_reass_handoff_error_strings,
2000   .format_trace = format_ip4_full_reass_handoff_trace,
2001
2002   .n_next_nodes = 1,
2003
2004   .next_nodes = {
2005     [0] = "error-drop",
2006   },
2007 };
2008
2009 VLIB_NODE_FN (ip4_full_reass_feature_handoff_node) (vlib_main_t * vm,
2010                                                     vlib_node_runtime_t *
2011                                                     node,
2012                                                     vlib_frame_t * frame)
2013 {
2014   return ip4_full_reass_handoff_node_inline (vm, node, frame, FEATURE,
2015                                              false /* is_local */);
2016 }
2017
2018 VLIB_REGISTER_NODE (ip4_full_reass_feature_handoff_node) = {
2019   .name = "ip4-full-reass-feature-hoff",
2020   .vector_size = sizeof (u32),
2021   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
2022   .error_strings = ip4_full_reass_handoff_error_strings,
2023   .format_trace = format_ip4_full_reass_handoff_trace,
2024
2025   .n_next_nodes = 1,
2026
2027   .next_nodes = {
2028     [0] = "error-drop",
2029   },
2030 };
2031
2032 VLIB_NODE_FN (ip4_full_reass_custom_handoff_node) (vlib_main_t * vm,
2033                                                     vlib_node_runtime_t *
2034                                                     node,
2035                                                     vlib_frame_t * frame)
2036 {
2037   return ip4_full_reass_handoff_node_inline (vm, node, frame, CUSTOM,
2038                                              false /* is_local */);
2039 }
2040
2041 VLIB_REGISTER_NODE (ip4_full_reass_custom_handoff_node) = {
2042   .name = "ip4-full-reass-custom-hoff",
2043   .vector_size = sizeof (u32),
2044   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
2045   .error_strings = ip4_full_reass_handoff_error_strings,
2046   .format_trace = format_ip4_full_reass_handoff_trace,
2047
2048   .n_next_nodes = 1,
2049
2050   .next_nodes = {
2051     [0] = "error-drop",
2052   },
2053 };
2054
2055 #ifndef CLIB_MARCH_VARIANT
2056 int
2057 ip4_full_reass_enable_disable_with_refcnt (u32 sw_if_index, int is_enable)
2058 {
2059   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
2060   vec_validate (rm->feature_use_refcount_per_intf, sw_if_index);
2061   if (is_enable)
2062     {
2063       if (!rm->feature_use_refcount_per_intf[sw_if_index])
2064         {
2065           ++rm->feature_use_refcount_per_intf[sw_if_index];
2066           return vnet_feature_enable_disable ("ip4-unicast",
2067                                               "ip4-full-reassembly-feature",
2068                                               sw_if_index, 1, 0, 0);
2069         }
2070       ++rm->feature_use_refcount_per_intf[sw_if_index];
2071     }
2072   else
2073     {
2074       --rm->feature_use_refcount_per_intf[sw_if_index];
2075       if (!rm->feature_use_refcount_per_intf[sw_if_index])
2076         return vnet_feature_enable_disable ("ip4-unicast",
2077                                             "ip4-full-reassembly-feature",
2078                                             sw_if_index, 0, 0, 0);
2079     }
2080   return -1;
2081 }
2082
2083 void
2084 ip4_local_full_reass_enable_disable (int enable)
2085 {
2086   if (enable)
2087     {
2088       ip4_full_reass_main.is_local_reass_enabled = 1;
2089     }
2090   else
2091     {
2092       ip4_full_reass_main.is_local_reass_enabled = 0;
2093     }
2094 }
2095
2096 int
2097 ip4_local_full_reass_enabled ()
2098 {
2099   return ip4_full_reass_main.is_local_reass_enabled;
2100 }
2101
2102 #endif
2103
2104 /*
2105  * fd.io coding-style-patch-verification: ON
2106  *
2107  * Local Variables:
2108  * eval: (c-set-style "gnu")
2109  * End:
2110  */