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, n_next = 0, to_next[VLIB_FRAME_SIZE];
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   u16 nexts[VLIB_FRAME_SIZE];
1170
1171   clib_spinlock_lock (&rt->lock);
1172
1173   n_left = frame->n_vectors;
1174   while (n_left > 0)
1175     {
1176       u32 bi0;
1177       vlib_buffer_t *b0;
1178       u32 next0;
1179       u32 error0 = IP4_ERROR_NONE;
1180
1181       bi0 = from[0];
1182       b0 = vlib_get_buffer (vm, bi0);
1183
1184       ip4_header_t *ip0 = vlib_buffer_get_current (b0);
1185       if (!ip4_get_fragment_more (ip0) && !ip4_get_fragment_offset (ip0))
1186         {
1187           // this is a whole packet - no fragmentation
1188           if (CUSTOM != type)
1189             {
1190               next0 = IP4_FULL_REASS_NEXT_INPUT;
1191             }
1192           else
1193             {
1194               next0 = vnet_buffer (b0)->ip.reass.next_index;
1195             }
1196           ip4_full_reass_add_trace (vm, node, NULL, bi0, PASSTHROUGH, 0, ~0);
1197           goto packet_enqueue;
1198         }
1199
1200       if (is_local && !rm->is_local_reass_enabled)
1201         {
1202           next0 = IP4_FULL_REASS_NEXT_DROP;
1203           goto packet_enqueue;
1204         }
1205
1206       const u32 fragment_first = ip4_get_fragment_offset_bytes (ip0);
1207       const u32 fragment_length =
1208         clib_net_to_host_u16 (ip0->length) - ip4_header_bytes (ip0);
1209       const u32 fragment_last = fragment_first + fragment_length - 1;
1210
1211       /* Keep track of received fragments */
1212       vlib_node_increment_counter (vm, node->node_index,
1213                                    IP4_ERROR_REASS_FRAGMENTS_RCVD, 1);
1214
1215       if (fragment_first > fragment_last ||
1216           fragment_first + fragment_length > UINT16_MAX - 20 ||
1217           (fragment_length < 8 && // 8 is minimum frag length per RFC 791
1218            ip4_get_fragment_more (ip0)))
1219         {
1220           next0 = IP4_FULL_REASS_NEXT_DROP;
1221           error0 = IP4_ERROR_REASS_MALFORMED_PACKET;
1222           goto packet_enqueue;
1223         }
1224
1225       u32 fib_index = (vnet_buffer (b0)->sw_if_index[VLIB_TX] == (u32) ~0) ?
1226                               vec_elt (ip4_main.fib_index_by_sw_if_index,
1227                                  vnet_buffer (b0)->sw_if_index[VLIB_RX]) :
1228                               vnet_buffer (b0)->sw_if_index[VLIB_TX];
1229
1230       ip4_full_reass_kv_t kv = { .k.fib_index = fib_index,
1231                                  .k.src.as_u32 = ip0->src_address.as_u32,
1232                                  .k.dst.as_u32 = ip0->dst_address.as_u32,
1233                                  .k.frag_id = ip0->fragment_id,
1234                                  .k.proto = ip0->protocol
1235
1236       };
1237       u8 do_handoff = 0;
1238
1239       ip4_full_reass_t *reass =
1240         ip4_full_reass_find_or_create (vm, node, rm, rt, &kv, &do_handoff);
1241
1242       if (reass)
1243         {
1244           const u32 fragment_first = ip4_get_fragment_offset_bytes (ip0);
1245           if (0 == fragment_first)
1246             {
1247               reass->sendout_thread_index = vm->thread_index;
1248             }
1249         }
1250
1251       if (PREDICT_FALSE (do_handoff))
1252         {
1253           next0 = IP4_FULL_REASS_NEXT_HANDOFF;
1254           vnet_buffer (b0)->ip.reass.owner_thread_index =
1255             kv.v.memory_owner_thread_index;
1256         }
1257       else if (reass)
1258         {
1259           u32 handoff_thread_idx;
1260           u32 counter = ~0;
1261           switch (ip4_full_reass_update (vm, node, rm, rt, reass, &bi0, &next0,
1262                                          &error0, CUSTOM == type,
1263                                          &handoff_thread_idx))
1264             {
1265             case IP4_REASS_RC_OK:
1266               /* nothing to do here */
1267               break;
1268             case IP4_REASS_RC_HANDOFF:
1269               next0 = IP4_FULL_REASS_NEXT_HANDOFF;
1270               b0 = vlib_get_buffer (vm, bi0);
1271               vnet_buffer (b0)->ip.reass.owner_thread_index =
1272                 handoff_thread_idx;
1273               break;
1274             case IP4_REASS_RC_TOO_MANY_FRAGMENTS:
1275               counter = IP4_ERROR_REASS_FRAGMENT_CHAIN_TOO_LONG;
1276               break;
1277             case IP4_REASS_RC_NO_BUF:
1278               counter = IP4_ERROR_REASS_NO_BUF;
1279               break;
1280             case IP4_REASS_RC_INTERNAL_ERROR:
1281               counter = IP4_ERROR_REASS_INTERNAL_ERROR;
1282               /* Sanitization is needed in internal error cases only, as
1283                * the incoming packet is already dropped in other cases,
1284                * also adding bi0 back to the reassembly list, fixes the
1285                * leaking of buffers during internal errors.
1286                *
1287                * Also it doesnt make sense to send these buffers custom
1288                * app, these fragments are with internal errors */
1289               sanitize_reass_buffers_add_missing (vm, reass, &bi0);
1290               reass->error_next_index = ~0;
1291               break;
1292             }
1293
1294           if (~0 != counter)
1295             {
1296               vlib_node_increment_counter (vm, node->node_index, counter, 1);
1297               ip4_full_reass_drop_all (vm, node, reass);
1298               ip4_full_reass_free (rm, rt, reass);
1299               goto next_packet;
1300             }
1301         }
1302       else
1303         {
1304           next0 = IP4_FULL_REASS_NEXT_DROP;
1305           error0 = IP4_ERROR_REASS_LIMIT_REACHED;
1306         }
1307
1308     packet_enqueue:
1309
1310       if (bi0 != ~0)
1311         {
1312           /* bi0 might have been updated by reass_finalize, reload */
1313           b0 = vlib_get_buffer (vm, bi0);
1314           if (IP4_ERROR_NONE != error0)
1315             {
1316               b0->error = node->errors[error0];
1317             }
1318
1319           if (next0 == IP4_FULL_REASS_NEXT_HANDOFF)
1320             {
1321               if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
1322                 {
1323                   ip4_full_reass_add_trace (
1324                     vm, node, NULL, bi0, HANDOFF, 0,
1325                     vnet_buffer (b0)->ip.reass.owner_thread_index);
1326                 }
1327             }
1328           else if (FEATURE == type && IP4_ERROR_NONE == error0)
1329             {
1330               vnet_feature_next (&next0, b0);
1331             }
1332
1333           /* Increment the counter to-custom-app also as this fragment is
1334            * also going to application */
1335           if (CUSTOM == type)
1336             {
1337               vlib_node_increment_counter (vm, node->node_index,
1338                                            IP4_ERROR_REASS_TO_CUSTOM_APP, 1);
1339             }
1340
1341           to_next[n_next] = bi0;
1342           nexts[n_next] = next0;
1343           n_next++;
1344           IP4_REASS_DEBUG_BUFFER (bi0, enqueue_next);
1345         }
1346
1347     next_packet:
1348       from += 1;
1349       n_left -= 1;
1350     }
1351
1352   clib_spinlock_unlock (&rt->lock);
1353
1354   vlib_buffer_enqueue_to_next (vm, node, to_next, nexts, n_next);
1355   return frame->n_vectors;
1356 }
1357
1358 VLIB_NODE_FN (ip4_full_reass_node) (vlib_main_t * vm,
1359                                     vlib_node_runtime_t * node,
1360                                     vlib_frame_t * frame)
1361 {
1362   return ip4_full_reass_inline (vm, node, frame, NORMAL, false /* is_local */);
1363 }
1364
1365 VLIB_REGISTER_NODE (ip4_full_reass_node) = {
1366     .name = "ip4-full-reassembly",
1367     .vector_size = sizeof (u32),
1368     .format_trace = format_ip4_full_reass_trace,
1369     .n_errors = IP4_N_ERROR,
1370     .error_counters = ip4_error_counters,
1371     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1372     .next_nodes =
1373         {
1374                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1375                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1376                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-full-reassembly-handoff",
1377
1378         },
1379 };
1380
1381 VLIB_NODE_FN (ip4_local_full_reass_node)
1382 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
1383 {
1384   return ip4_full_reass_inline (vm, node, frame, NORMAL, true /* is_local */);
1385 }
1386
1387 VLIB_REGISTER_NODE (ip4_local_full_reass_node) = {
1388     .name = "ip4-local-full-reassembly",
1389     .vector_size = sizeof (u32),
1390     .format_trace = format_ip4_full_reass_trace,
1391     .n_errors = IP4_N_ERROR,
1392     .error_counters = ip4_error_counters,
1393     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1394     .next_nodes =
1395         {
1396                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1397                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1398                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-local-full-reassembly-handoff",
1399
1400         },
1401 };
1402
1403 VLIB_NODE_FN (ip4_full_reass_node_feature) (vlib_main_t * vm,
1404                                             vlib_node_runtime_t * node,
1405                                             vlib_frame_t * frame)
1406 {
1407   return ip4_full_reass_inline (vm, node, frame, FEATURE,
1408                                 false /* is_local */);
1409 }
1410
1411 VLIB_REGISTER_NODE (ip4_full_reass_node_feature) = {
1412     .name = "ip4-full-reassembly-feature",
1413     .vector_size = sizeof (u32),
1414     .format_trace = format_ip4_full_reass_trace,
1415     .n_errors = IP4_N_ERROR,
1416     .error_counters = ip4_error_counters,
1417     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1418     .next_nodes =
1419         {
1420                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1421                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1422                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-full-reass-feature-hoff",
1423         },
1424 };
1425
1426 VNET_FEATURE_INIT (ip4_full_reass_feature, static) = {
1427     .arc_name = "ip4-unicast",
1428     .node_name = "ip4-full-reassembly-feature",
1429     .runs_before = VNET_FEATURES ("ip4-lookup",
1430                                   "ipsec4-input-feature"),
1431     .runs_after = 0,
1432 };
1433
1434 VLIB_NODE_FN (ip4_full_reass_node_custom) (vlib_main_t * vm,
1435                                            vlib_node_runtime_t * node,
1436                                            vlib_frame_t * frame)
1437 {
1438   return ip4_full_reass_inline (vm, node, frame, CUSTOM, false /* is_local */);
1439 }
1440
1441 VLIB_REGISTER_NODE (ip4_full_reass_node_custom) = {
1442     .name = "ip4-full-reassembly-custom",
1443     .vector_size = sizeof (u32),
1444     .format_trace = format_ip4_full_reass_trace,
1445     .n_errors = IP4_N_ERROR,
1446     .error_counters = ip4_error_counters,
1447     .n_next_nodes = IP4_FULL_REASS_N_NEXT,
1448     .next_nodes =
1449         {
1450                 [IP4_FULL_REASS_NEXT_INPUT] = "ip4-input",
1451                 [IP4_FULL_REASS_NEXT_DROP] = "ip4-drop",
1452                 [IP4_FULL_REASS_NEXT_HANDOFF] = "ip4-full-reass-custom-hoff",
1453         },
1454 };
1455
1456 VNET_FEATURE_INIT (ip4_full_reass_custom, static) = {
1457     .arc_name = "ip4-unicast",
1458     .node_name = "ip4-full-reassembly-feature",
1459     .runs_before = VNET_FEATURES ("ip4-lookup",
1460                                   "ipsec4-input-feature"),
1461     .runs_after = 0,
1462 };
1463
1464
1465 #ifndef CLIB_MARCH_VARIANT
1466 uword
1467 ip4_full_reass_custom_register_next_node (uword node_index)
1468 {
1469   return vlib_node_add_next (vlib_get_main (),
1470                              ip4_full_reass_node_custom.index, node_index);
1471 }
1472
1473 always_inline u32
1474 ip4_full_reass_get_nbuckets ()
1475 {
1476   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1477   u32 nbuckets;
1478   u8 i;
1479
1480   /* need more mem with more workers */
1481   nbuckets = (u32) (rm->max_reass_n * (vlib_num_workers () + 1) /
1482                     IP4_REASS_HT_LOAD_FACTOR);
1483
1484   for (i = 0; i < 31; i++)
1485     if ((1 << i) >= nbuckets)
1486       break;
1487   nbuckets = 1 << i;
1488
1489   return nbuckets;
1490 }
1491 #endif /* CLIB_MARCH_VARIANT */
1492
1493 typedef enum
1494 {
1495   IP4_EVENT_CONFIG_CHANGED = 1,
1496 } ip4_full_reass_event_t;
1497
1498 typedef struct
1499 {
1500   int failure;
1501   clib_bihash_16_8_t *new_hash;
1502 } ip4_rehash_cb_ctx;
1503
1504 #ifndef CLIB_MARCH_VARIANT
1505 static int
1506 ip4_rehash_cb (clib_bihash_kv_16_8_t * kv, void *_ctx)
1507 {
1508   ip4_rehash_cb_ctx *ctx = _ctx;
1509   if (clib_bihash_add_del_16_8 (ctx->new_hash, kv, 1))
1510     {
1511       ctx->failure = 1;
1512     }
1513   return (BIHASH_WALK_CONTINUE);
1514 }
1515
1516 static void
1517 ip4_full_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1518                            u32 max_reassembly_length,
1519                            u32 expire_walk_interval_ms)
1520 {
1521   ip4_full_reass_main.timeout_ms = timeout_ms;
1522   ip4_full_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1523   ip4_full_reass_main.max_reass_n = max_reassemblies;
1524   ip4_full_reass_main.max_reass_len = max_reassembly_length;
1525   ip4_full_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1526 }
1527
1528 vnet_api_error_t
1529 ip4_full_reass_set (u32 timeout_ms, u32 max_reassemblies,
1530                     u32 max_reassembly_length, u32 expire_walk_interval_ms)
1531 {
1532   u32 old_nbuckets = ip4_full_reass_get_nbuckets ();
1533   ip4_full_reass_set_params (timeout_ms, max_reassemblies,
1534                              max_reassembly_length, expire_walk_interval_ms);
1535   vlib_process_signal_event (ip4_full_reass_main.vlib_main,
1536                              ip4_full_reass_main.ip4_full_reass_expire_node_idx,
1537                              IP4_EVENT_CONFIG_CHANGED, 0);
1538   u32 new_nbuckets = ip4_full_reass_get_nbuckets ();
1539   if (ip4_full_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1540     {
1541       clib_bihash_16_8_t new_hash;
1542       clib_memset (&new_hash, 0, sizeof (new_hash));
1543       ip4_rehash_cb_ctx ctx;
1544       ctx.failure = 0;
1545       ctx.new_hash = &new_hash;
1546       clib_bihash_init_16_8 (&new_hash, "ip4-dr", new_nbuckets,
1547                              new_nbuckets * 1024);
1548       clib_bihash_foreach_key_value_pair_16_8 (&ip4_full_reass_main.hash,
1549                                                ip4_rehash_cb, &ctx);
1550       if (ctx.failure)
1551         {
1552           clib_bihash_free_16_8 (&new_hash);
1553           return -1;
1554         }
1555       else
1556         {
1557           clib_bihash_free_16_8 (&ip4_full_reass_main.hash);
1558           clib_memcpy_fast (&ip4_full_reass_main.hash, &new_hash,
1559                             sizeof (ip4_full_reass_main.hash));
1560           clib_bihash_copied (&ip4_full_reass_main.hash, &new_hash);
1561         }
1562     }
1563   return 0;
1564 }
1565
1566 vnet_api_error_t
1567 ip4_full_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1568                     u32 * max_reassembly_length,
1569                     u32 * expire_walk_interval_ms)
1570 {
1571   *timeout_ms = ip4_full_reass_main.timeout_ms;
1572   *max_reassemblies = ip4_full_reass_main.max_reass_n;
1573   *max_reassembly_length = ip4_full_reass_main.max_reass_len;
1574   *expire_walk_interval_ms = ip4_full_reass_main.expire_walk_interval_ms;
1575   return 0;
1576 }
1577
1578 static clib_error_t *
1579 ip4_full_reass_init_function (vlib_main_t * vm)
1580 {
1581   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1582   clib_error_t *error = 0;
1583   u32 nbuckets;
1584   vlib_node_t *node;
1585
1586   rm->vlib_main = vm;
1587
1588   vec_validate (rm->per_thread_data, vlib_num_workers ());
1589   ip4_full_reass_per_thread_t *rt;
1590   vec_foreach (rt, rm->per_thread_data)
1591   {
1592     clib_spinlock_init (&rt->lock);
1593     pool_alloc (rt->pool, rm->max_reass_n);
1594   }
1595
1596   node = vlib_get_node_by_name (vm, (u8 *) "ip4-full-reassembly-expire-walk");
1597   ASSERT (node);
1598   rm->ip4_full_reass_expire_node_idx = node->index;
1599
1600   ip4_full_reass_set_params (IP4_REASS_TIMEOUT_DEFAULT_MS,
1601                              IP4_REASS_MAX_REASSEMBLIES_DEFAULT,
1602                              IP4_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT,
1603                              IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1604
1605   nbuckets = ip4_full_reass_get_nbuckets ();
1606   clib_bihash_init_16_8 (&rm->hash, "ip4-dr", nbuckets, nbuckets * 1024);
1607
1608   rm->fq_index = vlib_frame_queue_main_init (ip4_full_reass_node.index, 0);
1609   rm->fq_local_index =
1610     vlib_frame_queue_main_init (ip4_local_full_reass_node.index, 0);
1611   rm->fq_feature_index =
1612     vlib_frame_queue_main_init (ip4_full_reass_node_feature.index, 0);
1613   rm->fq_custom_index =
1614     vlib_frame_queue_main_init (ip4_full_reass_node_custom.index, 0);
1615
1616   rm->feature_use_refcount_per_intf = NULL;
1617   rm->is_local_reass_enabled = 1;
1618
1619   return error;
1620 }
1621
1622 VLIB_INIT_FUNCTION (ip4_full_reass_init_function);
1623 #endif /* CLIB_MARCH_VARIANT */
1624
1625 static uword
1626 ip4_full_reass_walk_expired (vlib_main_t *vm, vlib_node_runtime_t *node,
1627                              CLIB_UNUSED (vlib_frame_t *f))
1628 {
1629   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1630   uword event_type, *event_data = 0;
1631
1632   while (true)
1633     {
1634       vlib_process_wait_for_event_or_clock (vm,
1635                                             (f64)
1636                                             rm->expire_walk_interval_ms /
1637                                             (f64) MSEC_PER_SEC);
1638       event_type = vlib_process_get_events (vm, &event_data);
1639
1640       switch (event_type)
1641         {
1642         case ~0:
1643           /* no events => timeout */
1644           /* fallthrough */
1645         case IP4_EVENT_CONFIG_CHANGED:
1646           /* nothing to do here */
1647           break;
1648         default:
1649           clib_warning ("BUG: event type 0x%wx", event_type);
1650           break;
1651         }
1652       f64 now = vlib_time_now (vm);
1653
1654       ip4_full_reass_t *reass;
1655       int *pool_indexes_to_free = NULL;
1656
1657       uword thread_index = 0;
1658       int index;
1659       const uword nthreads = vlib_num_workers () + 1;
1660
1661       for (thread_index = 0; thread_index < nthreads; ++thread_index)
1662         {
1663           ip4_full_reass_per_thread_t *rt =
1664             &rm->per_thread_data[thread_index];
1665           clib_spinlock_lock (&rt->lock);
1666
1667           vec_reset_length (pool_indexes_to_free);
1668
1669           /* Pace the number of timeouts handled per thread,to avoid barrier
1670            * sync issues in real world scenarios */
1671
1672           u32 beg = rt->last_id;
1673           /* to ensure we walk at least once per sec per context */
1674           u32 end =
1675             beg + (IP4_REASS_MAX_REASSEMBLIES_DEFAULT *
1676                      IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS / MSEC_PER_SEC +
1677                    1);
1678           if (end > vec_len (rt->pool))
1679             {
1680               end = vec_len (rt->pool);
1681               rt->last_id = 0;
1682             }
1683           else
1684             {
1685               rt->last_id = end;
1686             }
1687
1688           pool_foreach_stepping_index (index, beg, end, rt->pool)
1689           {
1690             reass = pool_elt_at_index (rt->pool, index);
1691             if (now > reass->last_heard + rm->timeout)
1692               {
1693                 vec_add1 (pool_indexes_to_free, index);
1694               }
1695           }
1696
1697           if (vec_len (pool_indexes_to_free))
1698             vlib_node_increment_counter (vm, node->node_index,
1699                                          IP4_ERROR_REASS_TIMEOUT,
1700                                          vec_len (pool_indexes_to_free));
1701           int *i;
1702           vec_foreach (i, pool_indexes_to_free)
1703           {
1704             ip4_full_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1705             ip4_full_reass_drop_all (vm, node, reass);
1706             ip4_full_reass_free (rm, rt, reass);
1707           }
1708
1709           clib_spinlock_unlock (&rt->lock);
1710         }
1711
1712       vec_free (pool_indexes_to_free);
1713       if (event_data)
1714         {
1715           vec_set_len (event_data, 0);
1716         }
1717     }
1718
1719   return 0;
1720 }
1721
1722 VLIB_REGISTER_NODE (ip4_full_reass_expire_node) = {
1723   .function = ip4_full_reass_walk_expired,
1724   .type = VLIB_NODE_TYPE_PROCESS,
1725   .name = "ip4-full-reassembly-expire-walk",
1726   .format_trace = format_ip4_full_reass_trace,
1727   .n_errors = IP4_N_ERROR,
1728   .error_counters = ip4_error_counters,
1729 };
1730
1731 static u8 *
1732 format_ip4_full_reass_key (u8 * s, va_list * args)
1733 {
1734   ip4_full_reass_key_t *key = va_arg (*args, ip4_full_reass_key_t *);
1735   s =
1736     format (s, "fib_index: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1737             key->fib_index, format_ip4_address, &key->src, format_ip4_address,
1738             &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1739   return s;
1740 }
1741
1742 static u8 *
1743 format_ip4_reass (u8 * s, va_list * args)
1744 {
1745   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1746   ip4_full_reass_t *reass = va_arg (*args, ip4_full_reass_t *);
1747
1748   s = format (s, "ID: %lu, key: %U\n  first_bi: %u, data_len: %u, "
1749               "last_packet_octet: %u, trace_op_counter: %u\n",
1750               reass->id, format_ip4_full_reass_key, &reass->key,
1751               reass->first_bi, reass->data_len,
1752               reass->last_packet_octet, reass->trace_op_counter);
1753
1754   u32 bi = reass->first_bi;
1755   u32 counter = 0;
1756   while (~0 != bi)
1757     {
1758       vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1759       vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1760       s =
1761         format (s,
1762                 "  #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1763                 "fragment[%u, %u]\n", counter, vnb->ip.reass.range_first,
1764                 vnb->ip.reass.range_last, bi,
1765                 ip4_full_reass_buffer_get_data_offset (b),
1766                 ip4_full_reass_buffer_get_data_len (b),
1767                 vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1768       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1769         {
1770           bi = b->next_buffer;
1771         }
1772       else
1773         {
1774           bi = ~0;
1775         }
1776     }
1777   return s;
1778 }
1779
1780 static clib_error_t *
1781 show_ip4_reass (vlib_main_t * vm,
1782                 unformat_input_t * input,
1783                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1784 {
1785   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1786
1787   vlib_cli_output (vm, "---------------------");
1788   vlib_cli_output (vm, "IP4 reassembly status");
1789   vlib_cli_output (vm, "---------------------");
1790   bool details = false;
1791   if (unformat (input, "details"))
1792     {
1793       details = true;
1794     }
1795
1796   u32 sum_reass_n = 0;
1797   ip4_full_reass_t *reass;
1798   uword thread_index;
1799   const uword nthreads = vlib_num_workers () + 1;
1800   for (thread_index = 0; thread_index < nthreads; ++thread_index)
1801     {
1802       ip4_full_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1803       clib_spinlock_lock (&rt->lock);
1804       if (details)
1805         {
1806           pool_foreach (reass, rt->pool) {
1807             vlib_cli_output (vm, "%U", format_ip4_reass, vm, reass);
1808           }
1809         }
1810       sum_reass_n += rt->reass_n;
1811       clib_spinlock_unlock (&rt->lock);
1812     }
1813   vlib_cli_output (vm, "---------------------");
1814   vlib_cli_output (vm, "Current full IP4 reassemblies count: %lu\n",
1815                    (long unsigned) sum_reass_n);
1816   vlib_cli_output (vm,
1817                    "Maximum configured concurrent full IP4 reassemblies per worker-thread: %lu\n",
1818                    (long unsigned) rm->max_reass_n);
1819   vlib_cli_output (vm,
1820                    "Maximum configured amount of fragments "
1821                    "per full IP4 reassembly: %lu\n",
1822                    (long unsigned) rm->max_reass_len);
1823   vlib_cli_output (vm,
1824                    "Maximum configured full IP4 reassembly timeout: %lums\n",
1825                    (long unsigned) rm->timeout_ms);
1826   vlib_cli_output (vm,
1827                    "Maximum configured full IP4 reassembly expire walk interval: %lums\n",
1828                    (long unsigned) rm->expire_walk_interval_ms);
1829   return 0;
1830 }
1831
1832 VLIB_CLI_COMMAND (show_ip4_full_reass_cmd, static) = {
1833     .path = "show ip4-full-reassembly",
1834     .short_help = "show ip4-full-reassembly [details]",
1835     .function = show_ip4_reass,
1836 };
1837
1838 #ifndef CLIB_MARCH_VARIANT
1839 vnet_api_error_t
1840 ip4_full_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1841 {
1842   return vnet_feature_enable_disable ("ip4-unicast",
1843                                       "ip4-full-reassembly-feature",
1844                                       sw_if_index, enable_disable, 0, 0);
1845 }
1846 #endif /* CLIB_MARCH_VARIANT */
1847
1848
1849 #define foreach_ip4_full_reass_handoff_error                       \
1850 _(CONGESTION_DROP, "congestion drop")
1851
1852
1853 typedef enum
1854 {
1855 #define _(sym,str) IP4_FULL_REASS_HANDOFF_ERROR_##sym,
1856   foreach_ip4_full_reass_handoff_error
1857 #undef _
1858     IP4_FULL_REASS_HANDOFF_N_ERROR,
1859 } ip4_full_reass_handoff_error_t;
1860
1861 static char *ip4_full_reass_handoff_error_strings[] = {
1862 #define _(sym,string) string,
1863   foreach_ip4_full_reass_handoff_error
1864 #undef _
1865 };
1866
1867 typedef struct
1868 {
1869   u32 next_worker_index;
1870 } ip4_full_reass_handoff_trace_t;
1871
1872 static u8 *
1873 format_ip4_full_reass_handoff_trace (u8 * s, va_list * args)
1874 {
1875   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1876   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1877   ip4_full_reass_handoff_trace_t *t =
1878     va_arg (*args, ip4_full_reass_handoff_trace_t *);
1879
1880   s =
1881     format (s, "ip4-full-reassembly-handoff: next-worker %d",
1882             t->next_worker_index);
1883
1884   return s;
1885 }
1886
1887 always_inline uword
1888 ip4_full_reass_handoff_node_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1889                                     vlib_frame_t *frame,
1890                                     ip4_full_reass_node_type_t type,
1891                                     bool is_local)
1892 {
1893   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
1894
1895   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1896   u32 n_enq, n_left_from, *from;
1897   u16 thread_indices[VLIB_FRAME_SIZE], *ti;
1898   u32 fq_index;
1899
1900   from = vlib_frame_vector_args (frame);
1901   n_left_from = frame->n_vectors;
1902   vlib_get_buffers (vm, from, bufs, n_left_from);
1903
1904   b = bufs;
1905   ti = thread_indices;
1906
1907   switch (type)
1908     {
1909     case NORMAL:
1910       if (is_local)
1911         {
1912           fq_index = rm->fq_local_index;
1913         }
1914       else
1915         {
1916           fq_index = rm->fq_index;
1917         }
1918       break;
1919     case FEATURE:
1920       fq_index = rm->fq_feature_index;
1921       break;
1922     case CUSTOM:
1923       fq_index = rm->fq_custom_index;
1924       break;
1925     default:
1926       clib_warning ("Unexpected `type' (%d)!", type);
1927     }
1928
1929   while (n_left_from > 0)
1930     {
1931       ti[0] = vnet_buffer (b[0])->ip.reass.owner_thread_index;
1932
1933       if (PREDICT_FALSE
1934           ((node->flags & VLIB_NODE_FLAG_TRACE)
1935            && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
1936         {
1937           ip4_full_reass_handoff_trace_t *t =
1938             vlib_add_trace (vm, node, b[0], sizeof (*t));
1939           t->next_worker_index = ti[0];
1940         }
1941
1942       n_left_from -= 1;
1943       ti += 1;
1944       b += 1;
1945     }
1946   n_enq = vlib_buffer_enqueue_to_thread (vm, node, fq_index, from,
1947                                          thread_indices, frame->n_vectors, 1);
1948
1949   if (n_enq < frame->n_vectors)
1950     vlib_node_increment_counter (vm, node->node_index,
1951                                  IP4_FULL_REASS_HANDOFF_ERROR_CONGESTION_DROP,
1952                                  frame->n_vectors - n_enq);
1953   return frame->n_vectors;
1954 }
1955
1956 VLIB_NODE_FN (ip4_full_reass_handoff_node) (vlib_main_t * vm,
1957                                             vlib_node_runtime_t * node,
1958                                             vlib_frame_t * frame)
1959 {
1960   return ip4_full_reass_handoff_node_inline (vm, node, frame, NORMAL,
1961                                              false /* is_local */);
1962 }
1963
1964
1965 VLIB_REGISTER_NODE (ip4_full_reass_handoff_node) = {
1966   .name = "ip4-full-reassembly-handoff",
1967   .vector_size = sizeof (u32),
1968   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
1969   .error_strings = ip4_full_reass_handoff_error_strings,
1970   .format_trace = format_ip4_full_reass_handoff_trace,
1971
1972   .n_next_nodes = 1,
1973
1974   .next_nodes = {
1975     [0] = "error-drop",
1976   },
1977 };
1978
1979 VLIB_NODE_FN (ip4_local_full_reass_handoff_node)
1980 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
1981 {
1982   return ip4_full_reass_handoff_node_inline (vm, node, frame, NORMAL,
1983                                              true /* is_local */);
1984 }
1985
1986 VLIB_REGISTER_NODE (ip4_local_full_reass_handoff_node) = {
1987   .name = "ip4-local-full-reassembly-handoff",
1988   .vector_size = sizeof (u32),
1989   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
1990   .error_strings = ip4_full_reass_handoff_error_strings,
1991   .format_trace = format_ip4_full_reass_handoff_trace,
1992
1993   .n_next_nodes = 1,
1994
1995   .next_nodes = {
1996     [0] = "error-drop",
1997   },
1998 };
1999
2000 VLIB_NODE_FN (ip4_full_reass_feature_handoff_node) (vlib_main_t * vm,
2001                                                     vlib_node_runtime_t *
2002                                                     node,
2003                                                     vlib_frame_t * frame)
2004 {
2005   return ip4_full_reass_handoff_node_inline (vm, node, frame, FEATURE,
2006                                              false /* is_local */);
2007 }
2008
2009 VLIB_REGISTER_NODE (ip4_full_reass_feature_handoff_node) = {
2010   .name = "ip4-full-reass-feature-hoff",
2011   .vector_size = sizeof (u32),
2012   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
2013   .error_strings = ip4_full_reass_handoff_error_strings,
2014   .format_trace = format_ip4_full_reass_handoff_trace,
2015
2016   .n_next_nodes = 1,
2017
2018   .next_nodes = {
2019     [0] = "error-drop",
2020   },
2021 };
2022
2023 VLIB_NODE_FN (ip4_full_reass_custom_handoff_node) (vlib_main_t * vm,
2024                                                     vlib_node_runtime_t *
2025                                                     node,
2026                                                     vlib_frame_t * frame)
2027 {
2028   return ip4_full_reass_handoff_node_inline (vm, node, frame, CUSTOM,
2029                                              false /* is_local */);
2030 }
2031
2032 VLIB_REGISTER_NODE (ip4_full_reass_custom_handoff_node) = {
2033   .name = "ip4-full-reass-custom-hoff",
2034   .vector_size = sizeof (u32),
2035   .n_errors = ARRAY_LEN(ip4_full_reass_handoff_error_strings),
2036   .error_strings = ip4_full_reass_handoff_error_strings,
2037   .format_trace = format_ip4_full_reass_handoff_trace,
2038
2039   .n_next_nodes = 1,
2040
2041   .next_nodes = {
2042     [0] = "error-drop",
2043   },
2044 };
2045
2046 #ifndef CLIB_MARCH_VARIANT
2047 int
2048 ip4_full_reass_enable_disable_with_refcnt (u32 sw_if_index, int is_enable)
2049 {
2050   ip4_full_reass_main_t *rm = &ip4_full_reass_main;
2051   vec_validate (rm->feature_use_refcount_per_intf, sw_if_index);
2052   if (is_enable)
2053     {
2054       if (!rm->feature_use_refcount_per_intf[sw_if_index])
2055         {
2056           ++rm->feature_use_refcount_per_intf[sw_if_index];
2057           return vnet_feature_enable_disable ("ip4-unicast",
2058                                               "ip4-full-reassembly-feature",
2059                                               sw_if_index, 1, 0, 0);
2060         }
2061       ++rm->feature_use_refcount_per_intf[sw_if_index];
2062     }
2063   else
2064     {
2065       --rm->feature_use_refcount_per_intf[sw_if_index];
2066       if (!rm->feature_use_refcount_per_intf[sw_if_index])
2067         return vnet_feature_enable_disable ("ip4-unicast",
2068                                             "ip4-full-reassembly-feature",
2069                                             sw_if_index, 0, 0, 0);
2070     }
2071   return -1;
2072 }
2073
2074 void
2075 ip4_local_full_reass_enable_disable (int enable)
2076 {
2077   if (enable)
2078     {
2079       ip4_full_reass_main.is_local_reass_enabled = 1;
2080     }
2081   else
2082     {
2083       ip4_full_reass_main.is_local_reass_enabled = 0;
2084     }
2085 }
2086
2087 int
2088 ip4_local_full_reass_enabled ()
2089 {
2090   return ip4_full_reass_main.is_local_reass_enabled;
2091 }
2092
2093 #endif
2094
2095 /*
2096  * fd.io coding-style-patch-verification: ON
2097  *
2098  * Local Variables:
2099  * eval: (c-set-style "gnu")
2100  * End:
2101  */