src/vnet/ip/ip4_reassembly.c

   1 /*
   2  * Copyright (c) 2017 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 /**
  17  * @file
  18  * @brief IPv4 Reassembly.
  19  *
  20  * This file contains the source code for IPv4 reassembly.
  21  */
  22
  23 #include <vppinfra/vec.h>
  24 #include <vnet/vnet.h>
  25 #include <vnet/ip/ip.h>
  26 #include <vppinfra/bihash_24_8.h>
  27 #include <vnet/ip/ip4_reassembly.h>
  28
  29 #define MSEC_PER_SEC 1000
  30 #define IP4_REASS_TIMEOUT_DEFAULT_MS 100
  31 #define IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS 10000 // 10 seconds default
  32 #define IP4_REASS_MAX_REASSEMBLIES_DEAFULT 1024
  33 #define IP4_REASS_HT_LOAD_FACTOR (0.75)
  34
  35 #define IP4_REASS_DEBUG_BUFFERS 0
  36 #if IP4_REASS_DEBUG_BUFFERS
  37 #define IP4_REASS_DEBUG_BUFFER(bi, what)             \
  38   do                                                 \
  39     {                                                \
  40       u32 _bi = bi;                                  \
  41       printf (#what "buffer %u", _bi);               \
  42       vlib_buffer_t *_b = vlib_get_buffer (vm, _bi); \
  43       while (_b->flags & VLIB_BUFFER_NEXT_PRESENT)   \
  44         {                                            \
  45           _bi = _b->next_buffer;                     \
  46           printf ("[%u]", _bi);                      \
  47           _b = vlib_get_buffer (vm, _bi);            \
  48         }                                            \
  49       printf ("\n");                                 \
  50       fflush (stdout);                               \
  51     }                                                \
  52   while (0)
  53 #else
  54 #define IP4_REASS_DEBUG_BUFFER(...)
  55 #endif
  56
  57 static vlib_node_registration_t ip4_reass_node;
  58
  59 typedef struct
  60 {
  61   union
  62   {
  63     struct
  64     {
  65       // align by making this 4 octets even though its a 2 octets field
  66       u32 xx_id;
  67       ip4_address_t src;
  68       ip4_address_t dst;
  69       // align by making this 4 octets even though its a 2 octets field
  70       u32 frag_id;
  71       // align by making this 4 octets even though its a 1 octet field
  72       u32 proto;
  73       u32 unused;
  74     };
  75     u64 as_u64[3];
  76   };
  77 } ip4_reass_key_t;
  78
  79 always_inline u32
  80 ip4_reass_buffer_get_data_offset_no_check (vlib_buffer_t * b)
  81 {
  82   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  83   return vnb->ip.reass.range_first - vnb->ip.reass.fragment_first;
  84 }
  85
  86 always_inline u32
  87 ip4_reass_buffer_get_data_offset (vlib_buffer_t * b)
  88 {
  89   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  90   ASSERT (vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first);
  91   return ip4_reass_buffer_get_data_offset_no_check (b);
  92 }
  93
  94 always_inline u16
  95 ip4_reass_buffer_get_data_len_no_check (vlib_buffer_t * b)
  96 {
  97   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  98   return clib_min (vnb->ip.reass.range_last, vnb->ip.reass.fragment_last) -
  99     (vnb->ip.reass.fragment_first + ip4_reass_buffer_get_data_offset (b)) + 1;
 100 }
 101
 102 always_inline u16
 103 ip4_reass_buffer_get_data_len (vlib_buffer_t * b)
 104 {
 105   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 106   ASSERT (vnb->ip.reass.range_last > vnb->ip.reass.fragment_first);
 107   return ip4_reass_buffer_get_data_len_no_check (b);
 108 }
 109
 110 typedef struct
 111 {
 112   // hash table key
 113   ip4_reass_key_t key;
 114   f64 first_heard;
 115   // time when last packet was received
 116   f64 last_heard;
 117   // internal id of this reassembly
 118   u32 id;
 119   // buffer index of first buffer in this reassembly context
 120   u32 first_bi;
 121   // last octet of packet, ~0 until fragment without more_fragments arrives
 122   u32 last_packet_octet;
 123   // length of data collected so far
 124   u32 data_len;
 125   // trace operation counter
 126   u32 trace_op_counter;
 127 } ip4_reass_t;
 128
 129 typedef struct
 130 {
 131   // IPv4 config
 132   u32 timeout_ms;
 133   f64 timeout;
 134   u32 expire_walk_interval_ms;
 135   u32 max_reass_n;
 136
 137   // IPv4 runtime
 138   ip4_reass_t *pool;
 139   clib_bihash_24_8_t hash;
 140   u32 reass_n;
 141   u32 id_counter;
 142   u32 buffers_n;
 143
 144   // convenience
 145   vlib_main_t *vlib_main;
 146   vnet_main_t *vnet_main;
 147
 148   // node index of ip4-drop node
 149   u32 ip4_drop_idx;
 150   u32 ip4_reass_expire_node_idx;
 151
 152 } ip4_reass_main_t;
 153
 154 ip4_reass_main_t ip4_reass_main;
 155
 156 typedef enum
 157 {
 158   IP4_REASSEMBLY_NEXT_INPUT,
 159   IP4_REASSEMBLY_NEXT_DROP,
 160   IP4_REASSEMBLY_N_NEXT,
 161 } ip4_reass_next_t;
 162
 163 typedef enum
 164 {
 165   RANGE_NEW,
 166   RANGE_SHRINK,
 167   RANGE_DISCARD,
 168   RANGE_OVERLAP,
 169   FINALIZE,
 170 } ip4_reass_trace_operation_e;
 171
 172 typedef struct
 173 {
 174   u16 range_first;
 175   u16 range_last;
 176   u32 range_bi;
 177   i32 data_offset;
 178   u32 data_len;
 179   u32 first_bi;
 180 } ip4_reass_range_trace_t;
 181
 182 typedef struct
 183 {
 184   ip4_reass_trace_operation_e action;
 185   u32 pool_index;
 186   u32 reass_id;
 187   ip4_reass_range_trace_t trace_range;
 188   u32 size_diff;
 189   u32 op_id;
 190   u32 fragment_first;
 191   u32 fragment_last;
 192   u32 total_data_len;
 193 } ip4_reass_trace_t;
 194
 195 void
 196 ip4_reass_trace_details (vlib_main_t * vm, u32 bi,
 197                          ip4_reass_range_trace_t * trace)
 198 {
 199   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 200   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 201   trace->range_first = vnb->ip.reass.range_first;
 202   trace->range_last = vnb->ip.reass.range_last;
 203   trace->data_offset = ip4_reass_buffer_get_data_offset_no_check (b);
 204   trace->data_len = ip4_reass_buffer_get_data_len_no_check (b);
 205   trace->range_bi = bi;
 206 }
 207
 208 u8 *
 209 format_ip4_reass_range_trace (u8 * s, va_list * args)
 210 {
 211   ip4_reass_range_trace_t *trace = va_arg (*args, ip4_reass_range_trace_t *);
 212   s = format (s, "range: [%u, %u], off %d, len %u, bi %u", trace->range_first,
 213               trace->range_last, trace->data_offset, trace->data_len,
 214               trace->range_bi);
 215   return s;
 216 }
 217
 218 u8 *
 219 format_ip4_reass_trace (u8 * s, va_list * args)
 220 {
 221   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
 222   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
 223   ip4_reass_trace_t *t = va_arg (*args, ip4_reass_trace_t *);
 224   s = format (s, "reass id: %u, op id: %u ", t->reass_id, t->op_id);
 225   u32 indent = format_get_indent (s);
 226   s = format (s, "first bi: %u, data len: %u, ip/fragment[%u, %u]",
 227               t->trace_range.first_bi, t->total_data_len, t->fragment_first,
 228               t->fragment_last);
 229   switch (t->action)
 230     {
 231     case RANGE_SHRINK:
 232       s = format (s, "\n%Ushrink %U by %u", format_white_space, indent,
 233                   format_ip4_reass_range_trace, &t->trace_range,
 234                   t->size_diff);
 235       break;
 236     case RANGE_DISCARD:
 237       s = format (s, "\n%Udiscard %U", format_white_space, indent,
 238                   format_ip4_reass_range_trace, &t->trace_range);
 239       break;
 240     case RANGE_NEW:
 241       s = format (s, "\n%Unew %U", format_white_space, indent,
 242                   format_ip4_reass_range_trace, &t->trace_range);
 243       break;
 244     case RANGE_OVERLAP:
 245       s = format (s, "\n%Uoverlapping/ignored %U", format_white_space, indent,
 246                   format_ip4_reass_range_trace, &t->trace_range);
 247       break;
 248     case FINALIZE:
 249       s = format (s, "\n%Ufinalize reassembly", format_white_space, indent);
 250       break;
 251     }
 252   return s;
 253 }
 254
 255 void
 256 ip4_reass_add_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
 257                      ip4_reass_main_t * rm, ip4_reass_t * reass, u32 bi,
 258                      ip4_reass_trace_operation_e action, u32 size_diff)
 259 {
 260   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 261   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 262   ip4_reass_trace_t *t = vlib_add_trace (vm, node, b, sizeof (t[0]));
 263   t->pool_index = reass - rm->pool;
 264   t->reass_id = reass->id;
 265   t->action = action;
 266   ip4_reass_trace_details (vm, bi, &t->trace_range);
 267   t->size_diff = size_diff;
 268   t->op_id = reass->trace_op_counter;
 269   ++reass->trace_op_counter;
 270   t->fragment_first = vnb->ip.reass.fragment_first;
 271   t->fragment_last = vnb->ip.reass.fragment_last;
 272   t->trace_range.first_bi = reass->first_bi;
 273   t->total_data_len = reass->data_len;
 274 #if 0
 275   static u8 *s = NULL;
 276   s = format (s, "%U", format_ip4_reass_trace, NULL, NULL, t);
 277   printf ("%.*s\n", vec_len (s), s);
 278   fflush (stdout);
 279   vec_reset_length (s);
 280 #endif
 281 }
 282
 283 void
 284 ip4_reass_free (ip4_reass_main_t * rm, ip4_reass_t * reass)
 285 {
 286   clib_bihash_kv_24_8_t kv;
 287   kv.key[0] = reass->key.as_u64[0];
 288   kv.key[1] = reass->key.as_u64[1];
 289   kv.key[2] = reass->key.as_u64[2];
 290   clib_bihash_add_del_24_8 (&rm->hash, &kv, 0);
 291   pool_put (rm->pool, reass);
 292   --rm->reass_n;
 293 }
 294
 295 static void
 296 ip4_reass_on_timeout (vlib_main_t * vm, ip4_reass_main_t * rm,
 297                       ip4_reass_t * reass, u32 ** vec_drop_timeout)
 298 {
 299   u32 range_bi = reass->first_bi;
 300   vlib_buffer_t *range_b;
 301   vnet_buffer_opaque_t *range_vnb;
 302   while (~0 != range_bi)
 303     {
 304       range_b = vlib_get_buffer (vm, range_bi);
 305       range_vnb = vnet_buffer (range_b);
 306       u32 bi = range_bi;
 307       while (~0 != bi)
 308         {
 309           vec_add1 (*vec_drop_timeout, bi);
 310           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 311           if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 312             {
 313               bi = b->next_buffer;
 314               b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 315             }
 316           else
 317             {
 318               bi = ~0;
 319             }
 320         }
 321       range_bi = range_vnb->ip.reass.next_range_bi;
 322     }
 323 }
 324
 325 ip4_reass_t *
 326 ip4_reass_find_or_create (vlib_main_t * vm, ip4_reass_main_t * rm,
 327                           ip4_reass_key_t * k, u32 ** vec_drop_timeout)
 328 {
 329   ip4_reass_t *reass = NULL;
 330   f64 now = vlib_time_now (rm->vlib_main);
 331   clib_bihash_kv_24_8_t kv, value;
 332   kv.key[0] = k->as_u64[0];
 333   kv.key[1] = k->as_u64[1];
 334   kv.key[2] = k->as_u64[2];
 335
 336   if (!clib_bihash_search_24_8 (&rm->hash, &kv, &value))
 337     {
 338       reass = pool_elt_at_index (rm->pool, value.value);
 339       if (now > reass->last_heard + rm->timeout)
 340         {
 341           ip4_reass_on_timeout (vm, rm, reass, vec_drop_timeout);
 342           ip4_reass_free (rm, reass);
 343           reass = NULL;
 344         }
 345     }
 346
 347   if (reass)
 348     {
 349       reass->last_heard = now;
 350       return reass;
 351     }
 352
 353   if (rm->reass_n >= rm->max_reass_n)
 354     {
 355       reass = NULL;
 356       return reass;
 357     }
 358   else
 359     {
 360       pool_get (rm->pool, reass);
 361       memset (reass, 0, sizeof (*reass));
 362       reass->id = rm->id_counter;
 363       ++rm->id_counter;
 364       reass->first_bi = ~0;
 365       reass->last_packet_octet = ~0;
 366       reass->data_len = 0;
 367       ++rm->reass_n;
 368     }
 369
 370   reass->key.as_u64[0] = kv.key[0] = k->as_u64[0];
 371   reass->key.as_u64[1] = kv.key[1] = k->as_u64[1];
 372   reass->key.as_u64[2] = kv.key[2] = k->as_u64[2];
 373   kv.value = reass - rm->pool;
 374   reass->last_heard = now;
 375
 376   if (clib_bihash_add_del_24_8 (&rm->hash, &kv, 1))
 377     {
 378       ip4_reass_free (rm, reass);
 379       reass = NULL;
 380     }
 381
 382   return reass;
 383 }
 384
 385 void
 386 ip4_reass_finalize (vlib_main_t * vm, vlib_node_runtime_t * node,
 387                     ip4_reass_main_t * rm, ip4_reass_t * reass, u32 * bi0,
 388                     u32 * next0, vlib_error_t * error0, u32 next_input,
 389                     u32 ** vec_drop_compress, u32 ** vec_drop_overlap)
 390 {
 391   ASSERT (~0 != reass->first_bi);
 392   vlib_buffer_t *first_b = vlib_get_buffer (vm, reass->first_bi);
 393   vlib_buffer_t *last_b = NULL;
 394   u32 sub_chain_bi = reass->first_bi;
 395   u32 total_length = 0;
 396   u32 buf_cnt = 0;
 397   u32 dropped_cnt = 0;
 398   do
 399     {
 400       u32 tmp_bi = sub_chain_bi;
 401       vlib_buffer_t *tmp = vlib_get_buffer (vm, tmp_bi);
 402       ip4_header_t *ip = vlib_buffer_get_current (tmp);
 403       u32 data_len = ip4_reass_buffer_get_data_len (tmp);
 404       u32 trim_front =
 405         ip4_header_bytes (ip) + ip4_reass_buffer_get_data_offset (tmp);
 406       u32 trim_end =
 407         vlib_buffer_length_in_chain (vm, tmp) - trim_front - data_len;
 408       if (tmp_bi == reass->first_bi)
 409         {
 410           /* first buffer - keep ip4 header */
 411           ASSERT (0 == ip4_reass_buffer_get_data_offset (tmp));
 412           trim_front = 0;
 413           trim_end = vlib_buffer_length_in_chain (vm, tmp) - data_len -
 414             ip4_header_bytes (ip);
 415           ASSERT (vlib_buffer_length_in_chain (vm, tmp) - trim_end > 0);
 416         }
 417       u32 keep_data =
 418         vlib_buffer_length_in_chain (vm, tmp) - trim_front - trim_end;
 419       while (1)
 420         {
 421           ++buf_cnt;
 422           if (trim_front)
 423             {
 424               if (trim_front > tmp->current_length)
 425                 {
 426                   /* drop whole buffer */
 427                   vec_add1 (*vec_drop_compress, tmp_bi);
 428                   ++dropped_cnt;
 429                   trim_front -= tmp->current_length;
 430                   ASSERT (tmp->flags & VLIB_BUFFER_NEXT_PRESENT);
 431                   tmp->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 432                   tmp_bi = tmp->next_buffer;
 433                   tmp = vlib_get_buffer (vm, tmp_bi);
 434                   continue;
 435                 }
 436               else
 437                 {
 438                   vlib_buffer_advance (tmp, trim_front);
 439                   trim_front = 0;
 440                 }
 441             }
 442           if (keep_data)
 443             {
 444               if (last_b)
 445                 {
 446                   last_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
 447                   last_b->next_buffer = tmp_bi;
 448                 }
 449               last_b = tmp;
 450               if (keep_data <= tmp->current_length)
 451                 {
 452                   tmp->current_length = keep_data;
 453                   keep_data = 0;
 454                 }
 455               else
 456                 {
 457                   keep_data -= tmp->current_length;
 458                   ASSERT (tmp->flags & VLIB_BUFFER_NEXT_PRESENT);
 459                 }
 460               total_length += tmp->current_length;
 461             }
 462           else
 463             {
 464               vec_add1 (*vec_drop_overlap, tmp_bi);
 465               ASSERT (reass->first_bi != tmp_bi);
 466               ++dropped_cnt;
 467             }
 468           if (tmp->flags & VLIB_BUFFER_NEXT_PRESENT)
 469             {
 470               tmp_bi = tmp->next_buffer;
 471               tmp = vlib_get_buffer (vm, tmp->next_buffer);
 472             }
 473           else
 474             {
 475               break;
 476             }
 477         }
 478       sub_chain_bi =
 479         vnet_buffer (vlib_get_buffer (vm, sub_chain_bi))->ip.
 480         reass.next_range_bi;
 481     }
 482   while (~0 != sub_chain_bi);
 483   last_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 484   ASSERT (rm->buffers_n >= (buf_cnt - dropped_cnt));
 485   rm->buffers_n -= buf_cnt - dropped_cnt;
 486   ASSERT (total_length >= first_b->current_length);
 487   total_length -= first_b->current_length;
 488   first_b->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
 489   first_b->total_length_not_including_first_buffer = total_length;
 490   ip4_header_t *ip = vlib_buffer_get_current (first_b);
 491   ip->flags_and_fragment_offset = 0;
 492   ip->length = clib_host_to_net_u16 (first_b->current_length + total_length);
 493   ip->checksum = ip4_header_checksum (ip);
 494   vlib_buffer_chain_compress (vm, first_b, vec_drop_compress);
 495   if (PREDICT_FALSE (first_b->flags & VLIB_BUFFER_IS_TRACED))
 496     {
 497       ip4_reass_add_trace (vm, node, rm, reass, reass->first_bi, FINALIZE, 0);
 498 #if 0
 499       // following code does a hexdump of packet fragments to stdout ...
 500       do
 501         {
 502           u32 bi = reass->first_bi;
 503           u8 *s = NULL;
 504           while (~0 != bi)
 505             {
 506               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 507               s = format (s, "%u: %U\n", bi, format_hexdump,
 508                           vlib_buffer_get_current (b), b->current_length);
 509               if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 510                 {
 511                   bi = b->next_buffer;
 512                 }
 513               else
 514                 {
 515                   break;
 516                 }
 517             }
 518           printf ("%.*s\n", vec_len (s), s);
 519           fflush (stdout);
 520           vec_free (s);
 521         }
 522       while (0);
 523 #endif
 524     }
 525   *bi0 = reass->first_bi;
 526   *next0 = next_input;
 527   *error0 = IP4_ERROR_NONE;
 528   ip4_reass_free (rm, reass);
 529   reass = NULL;
 530 }
 531
 532 static u32
 533 ip4_reass_get_buffer_chain_length (vlib_main_t * vm, vlib_buffer_t * b)
 534 {
 535   u32 len = 0;
 536   while (b)
 537     {
 538       ++len;
 539       if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
 540         {
 541           b = vlib_get_buffer (vm, b->next_buffer);
 542         }
 543       else
 544         {
 545           break;
 546         }
 547     }
 548   return len;
 549 }
 550
 551 static void
 552 ip4_reass_insert_range_in_chain (vlib_main_t * vm,
 553                                  ip4_reass_main_t * rm,
 554                                  ip4_reass_t * reass,
 555                                  u32 prev_range_bi, u32 new_next_bi)
 556 {
 557
 558   vlib_buffer_t *new_next_b = vlib_get_buffer (vm, new_next_bi);
 559   vnet_buffer_opaque_t *new_next_vnb = vnet_buffer (new_next_b);
 560   if (~0 != prev_range_bi)
 561     {
 562       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
 563       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
 564       new_next_vnb->ip.reass.next_range_bi = prev_vnb->ip.reass.next_range_bi;
 565       prev_vnb->ip.reass.next_range_bi = new_next_bi;
 566     }
 567   else
 568     {
 569       if (~0 != reass->first_bi)
 570         {
 571           new_next_vnb->ip.reass.next_range_bi = reass->first_bi;
 572         }
 573       reass->first_bi = new_next_bi;
 574     }
 575   reass->data_len += ip4_reass_buffer_get_data_len (new_next_b);
 576   rm->buffers_n += ip4_reass_get_buffer_chain_length (vm, new_next_b);
 577 }
 578
 579 static void
 580 ip4_reass_remove_range_from_chain (vlib_main_t * vm,
 581                                    vlib_node_runtime_t * node,
 582                                    ip4_reass_main_t * rm,
 583                                    u32 ** vec_drop_overlap,
 584                                    ip4_reass_t * reass, u32 prev_range_bi,
 585                                    u32 discard_bi)
 586 {
 587   vlib_buffer_t *discard_b = vlib_get_buffer (vm, discard_bi);
 588   vnet_buffer_opaque_t *discard_vnb = vnet_buffer (discard_b);
 589   if (~0 != prev_range_bi)
 590     {
 591       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
 592       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
 593       ASSERT (prev_vnb->ip.reass.next_range_bi == discard_bi);
 594       prev_vnb->ip.reass.next_range_bi = discard_vnb->ip.reass.next_range_bi;
 595     }
 596   else
 597     {
 598       reass->first_bi = discard_vnb->ip.reass.next_range_bi;
 599     }
 600   reass->data_len -= ip4_reass_buffer_get_data_len (discard_b);
 601   while (1)
 602     {
 603       vec_add1 (*vec_drop_overlap, discard_bi);
 604       if (PREDICT_FALSE (discard_b->flags & VLIB_BUFFER_IS_TRACED))
 605         {
 606           ip4_reass_add_trace (vm, node, rm, reass, discard_bi, RANGE_DISCARD,
 607                                0);
 608         }
 609       if (discard_b->flags & VLIB_BUFFER_NEXT_PRESENT)
 610         {
 611           discard_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 612           discard_bi = discard_b->next_buffer;
 613           discard_b = vlib_get_buffer (vm, discard_bi);
 614         }
 615       else
 616         {
 617           break;
 618         }
 619     }
 620 }
 621
 622 void
 623 ip4_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
 624                   ip4_reass_main_t * rm, ip4_reass_t * reass, u32 * bi0,
 625                   u32 * next0, vlib_error_t * error0,
 626                   u32 ** vec_drop_overlap, u32 ** vec_drop_compress,
 627                   u32 next_input, u32 next_drop)
 628 {
 629   int consumed = 0;
 630   vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
 631   ip4_header_t *fip = vlib_buffer_get_current (fb);
 632   ASSERT (fb->current_length >= sizeof (*fip));
 633   vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
 634   u32 fragment_first = fvnb->ip.reass.fragment_first =
 635     ip4_get_fragment_offset_bytes (fip);
 636   u32 fragment_length =
 637     clib_net_to_host_u16 (fip->length) - ip4_header_bytes (fip);
 638   u32 fragment_last = fvnb->ip.reass.fragment_last =
 639     fragment_first + fragment_length - 1;
 640   int more_fragments = ip4_get_fragment_more (fip);
 641   u32 candidate_range_bi = reass->first_bi;
 642   u32 prev_range_bi = ~0;
 643   fvnb->ip.reass.range_first = fragment_first;
 644   fvnb->ip.reass.range_last = fragment_last;
 645   fvnb->ip.reass.next_range_bi = ~0;
 646   if (!more_fragments)
 647     {
 648       reass->last_packet_octet = fragment_last;
 649     }
 650   if (~0 == reass->first_bi)
 651     {
 652       // starting a new reassembly
 653       ip4_reass_insert_range_in_chain (vm, rm, reass, prev_range_bi, *bi0);
 654       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 655         {
 656           ip4_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
 657         }
 658       *bi0 = ~0;
 659       fvnb->ip.reass.estimated_mtu = clib_net_to_host_u16 (fip->length);
 660       return;
 661     }
 662   fvnb->ip.reass.estimated_mtu = clib_min (clib_net_to_host_u16 (fip->length),
 663                                            fvnb->ip.reass.estimated_mtu);
 664   while (~0 != candidate_range_bi)
 665     {
 666       vlib_buffer_t *candidate_b = vlib_get_buffer (vm, candidate_range_bi);
 667       vnet_buffer_opaque_t *candidate_vnb = vnet_buffer (candidate_b);
 668       if (fragment_first > candidate_vnb->ip.reass.range_last)
 669         {
 670           // this fragments starts after candidate range
 671           prev_range_bi = candidate_range_bi;
 672           candidate_range_bi = candidate_vnb->ip.reass.next_range_bi;
 673           if (candidate_vnb->ip.reass.range_last < fragment_last &&
 674               ~0 == candidate_range_bi)
 675             {
 676               // special case - this fragment falls beyond all known ranges
 677               ip4_reass_insert_range_in_chain (vm, rm, reass, prev_range_bi,
 678                                                *bi0);
 679               consumed = 1;
 680               break;
 681             }
 682           continue;
 683         }
 684       if (fragment_last < candidate_vnb->ip.reass.range_first)
 685         {
 686           // this fragment ends before candidate range without any overlap
 687           ip4_reass_insert_range_in_chain (vm, rm, reass, prev_range_bi,
 688                                            *bi0);
 689           consumed = 1;
 690         }
 691       else
 692         {
 693           if (fragment_first >= candidate_vnb->ip.reass.range_first &&
 694               fragment_last <= candidate_vnb->ip.reass.range_last)
 695             {
 696               // this fragment is a (sub)part of existing range, ignore it
 697               if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 698                 {
 699                   ip4_reass_add_trace (vm, node, rm, reass, *bi0,
 700                                        RANGE_OVERLAP, 0);
 701                 }
 702               break;
 703             }
 704           int discard_candidate = 0;
 705           if (fragment_first < candidate_vnb->ip.reass.range_first)
 706             {
 707               u32 overlap =
 708                 fragment_last - candidate_vnb->ip.reass.range_first + 1;
 709               if (overlap < ip4_reass_buffer_get_data_len (candidate_b))
 710                 {
 711                   candidate_vnb->ip.reass.range_first += overlap;
 712                   ASSERT (reass->data_len >= overlap);
 713                   reass->data_len -= overlap;
 714                   if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 715                     {
 716                       ip4_reass_add_trace (vm, node, rm, reass,
 717                                            candidate_range_bi, RANGE_SHRINK,
 718                                            overlap);
 719                     }
 720                   ip4_reass_insert_range_in_chain (vm, rm, reass,
 721                                                    prev_range_bi, *bi0);
 722                   consumed = 1;
 723                 }
 724               else
 725                 {
 726                   discard_candidate = 1;
 727                 }
 728             }
 729           else if (fragment_last > candidate_vnb->ip.reass.range_last)
 730             {
 731               u32 overlap =
 732                 candidate_vnb->ip.reass.range_last - fragment_first + 1;
 733               if (overlap < ip4_reass_buffer_get_data_len (candidate_b))
 734                 {
 735                   fvnb->ip.reass.range_first += overlap;
 736                   if (~0 != candidate_vnb->ip.reass.next_range_bi)
 737                     {
 738                       prev_range_bi = candidate_range_bi;
 739                       candidate_range_bi =
 740                         candidate_vnb->ip.reass.next_range_bi;
 741                       continue;
 742                     }
 743                   else
 744                     {
 745                       // special case - last range discarded
 746                       ip4_reass_insert_range_in_chain (vm, rm, reass,
 747                                                        candidate_range_bi,
 748                                                        *bi0);
 749                       consumed = 1;
 750                     }
 751                 }
 752               else
 753                 {
 754                   discard_candidate = 1;
 755                 }
 756             }
 757           else
 758             {
 759               discard_candidate = 1;
 760             }
 761           if (discard_candidate)
 762             {
 763               u32 next_range_bi = candidate_vnb->ip.reass.next_range_bi;
 764               // discard candidate range, probe next range
 765               ip4_reass_remove_range_from_chain (vm, node, rm,
 766                                                  vec_drop_overlap, reass,
 767                                                  prev_range_bi,
 768                                                  candidate_range_bi);
 769               if (~0 != next_range_bi)
 770                 {
 771                   candidate_range_bi = next_range_bi;
 772                   continue;
 773                 }
 774               else
 775                 {
 776                   // special case - last range discarded
 777                   ip4_reass_insert_range_in_chain (vm, rm, reass,
 778                                                    prev_range_bi, *bi0);
 779                   consumed = 1;
 780                 }
 781             }
 782         }
 783       break;
 784     }
 785   if (consumed)
 786     {
 787       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 788         {
 789           ip4_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
 790         }
 791     }
 792   if (~0 != reass->last_packet_octet &&
 793       reass->data_len == reass->last_packet_octet + 1)
 794     {
 795       ip4_reass_finalize (vm, node, rm, reass, bi0, next0, error0, next_input,
 796                           vec_drop_compress, vec_drop_overlap);
 797     }
 798   else
 799     {
 800       if (consumed)
 801         {
 802           *bi0 = ~0;
 803         }
 804       else
 805         {
 806           *next0 = next_drop;
 807           *error0 = IP4_ERROR_REASS_DUPLICATE_FRAGMENT;
 808         }
 809     }
 810 }
 811
 812 always_inline uword
 813 ip4_reassembly (vlib_main_t * vm, vlib_node_runtime_t * node,
 814                 vlib_frame_t * frame)
 815 {
 816   u32 *from = vlib_frame_vector_args (frame);
 817   u32 n_left_from, n_left_to_next, *to_next, next_index;
 818   ip4_reass_main_t *rm = &ip4_reass_main;
 819
 820   n_left_from = frame->n_vectors;
 821   next_index = node->cached_next_index;
 822   static u32 *vec_drop_timeout = NULL;  // indexes of buffers which timed out
 823   static u32 *vec_drop_overlap = NULL;  // indexes of buffers which were discarded due to overlap
 824   static u32 *vec_drop_compress = NULL; // indexes of buffers dicarded due to buffer compression
 825   while (n_left_from > 0 || vec_len (vec_drop_timeout) > 0 ||
 826          vec_len (vec_drop_overlap) > 0)
 827     {
 828       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 829
 830       while (vec_len (vec_drop_timeout) > 0 && n_left_to_next > 0)
 831         {
 832           u32 bi = vec_pop (vec_drop_timeout);
 833           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 834           b->error = node->errors[IP4_ERROR_REASS_TIMEOUT];
 835           to_next[0] = bi;
 836           to_next += 1;
 837           n_left_to_next -= 1;
 838           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 839                                            n_left_to_next, bi,
 840                                            IP4_REASSEMBLY_NEXT_DROP);
 841           IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_timeout);
 842           ASSERT (rm->buffers_n > 0);
 843           --rm->buffers_n;
 844         }
 845
 846       while (vec_len (vec_drop_overlap) > 0 && n_left_to_next > 0)
 847         {
 848           u32 bi = vec_pop (vec_drop_overlap);
 849           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 850           b->error = node->errors[IP4_ERROR_REASS_DUPLICATE_FRAGMENT];
 851           to_next[0] = bi;
 852           to_next += 1;
 853           n_left_to_next -= 1;
 854           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 855                                            n_left_to_next, bi,
 856                                            IP4_REASSEMBLY_NEXT_DROP);
 857           IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_duplicate_fragment);
 858           ASSERT (rm->buffers_n > 0);
 859           --rm->buffers_n;
 860         }
 861
 862       while (vec_len (vec_drop_compress) > 0 && n_left_to_next > 0)
 863         {
 864           u32 bi = vec_pop (vec_drop_compress);
 865           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 866           b->error = node->errors[IP4_ERROR_NONE];
 867           to_next[0] = bi;
 868           to_next += 1;
 869           n_left_to_next -= 1;
 870           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 871                                            n_left_to_next, bi,
 872                                            IP4_REASSEMBLY_NEXT_DROP);
 873           IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_compress);
 874           ASSERT (rm->buffers_n > 0);
 875           --rm->buffers_n;
 876         }
 877
 878       while (n_left_from > 0 && n_left_to_next > 0)
 879         {
 880           u32 bi0;
 881           vlib_buffer_t *b0;
 882           u32 next0;            //, error0;
 883
 884           bi0 = from[0];
 885           b0 = vlib_get_buffer (vm, bi0);
 886
 887           ip4_header_t *ip0 = vlib_buffer_get_current (b0);
 888           ip4_reass_key_t k;
 889           k.src.as_u32 = ip0->src_address.as_u32;
 890           k.dst.as_u32 = ip0->dst_address.as_u32;
 891           k.xx_id = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 892           k.frag_id = ip0->fragment_id;
 893           k.proto = ip0->protocol;
 894           k.unused = 0;
 895           ip4_reass_t *reass =
 896             ip4_reass_find_or_create (vm, rm, &k, &vec_drop_timeout);
 897
 898           u32 error0 = IP4_ERROR_NONE;
 899           if (reass)
 900             {
 901               ip4_reass_update (vm, node, rm, reass, &bi0, &next0, &error0,
 902                                 &vec_drop_overlap, &vec_drop_compress,
 903                                 IP4_REASSEMBLY_NEXT_INPUT,
 904                                 IP4_REASSEMBLY_NEXT_DROP);
 905             }
 906           else
 907             {
 908               next0 = IP4_REASSEMBLY_NEXT_DROP;
 909               error0 = IP4_ERROR_REASS_LIMIT_REACHED;
 910             }
 911
 912           b0->error = node->errors[error0];
 913
 914           if (bi0 != ~0)
 915             {
 916               to_next[0] = bi0;
 917               to_next += 1;
 918               n_left_to_next -= 1;
 919               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 920                                                n_left_to_next, bi0, next0);
 921               IP4_REASS_DEBUG_BUFFER (bi0, enqueue_next);
 922             }
 923
 924           from += 1;
 925           n_left_from -= 1;
 926         }
 927
 928       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 929     }
 930
 931   return frame->n_vectors;
 932 }
 933
 934 static char *ip4_reassembly_error_strings[] = {
 935 #define _(sym, string) string,
 936   foreach_ip4_error
 937 #undef _
 938 };
 939
 940 /* *INDENT-OFF* */
 941 VLIB_REGISTER_NODE (ip4_reass_node, static) = {
 942     .function = ip4_reassembly,
 943     .name = "ip4-reassembly",
 944     .vector_size = sizeof (u32),
 945     .format_trace = format_ip4_reass_trace,
 946     .n_errors = ARRAY_LEN (ip4_reassembly_error_strings),
 947     .error_strings = ip4_reassembly_error_strings,
 948     .n_next_nodes = IP4_REASSEMBLY_N_NEXT,
 949     .next_nodes =
 950         {
 951                 [IP4_REASSEMBLY_NEXT_INPUT] = "ip4-input",
 952                 [IP4_REASSEMBLY_NEXT_DROP] = "ip4-drop",
 953         },
 954 };
 955 /* *INDENT-ON* */
 956
 957 VLIB_NODE_FUNCTION_MULTIARCH (ip4_reass_node, ip4_reassembly)
 958      static u32 ip4_reass_get_nbuckets ()
 959 {
 960   ip4_reass_main_t *rm = &ip4_reass_main;
 961   u32 nbuckets;
 962   u8 i;
 963
 964   nbuckets = (u32) (rm->max_reass_n / IP4_REASS_HT_LOAD_FACTOR);
 965
 966   for (i = 0; i < 31; i++)
 967     if ((1 << i) >= nbuckets)
 968       break;
 969   nbuckets = 1 << i;
 970
 971   return nbuckets;
 972 }
 973
 974 typedef enum
 975 {
 976   IP4_EVENT_CONFIG_CHANGED = 1,
 977 } ip4_reass_event_t;
 978
 979 typedef struct
 980 {
 981   int failure;
 982   clib_bihash_24_8_t *new_hash;
 983 } ip4_rehash_cb_ctx;
 984
 985 void
 986 ip4_rehash_cb (clib_bihash_kv_24_8_t * kv, void *_ctx)
 987 {
 988   ip4_rehash_cb_ctx *ctx = _ctx;
 989   if (clib_bihash_add_del_24_8 (ctx->new_hash, kv, 1))
 990     {
 991       ctx->failure = 1;
 992     }
 993 }
 994
 995 vnet_api_error_t
 996 ip4_reass_set (u32 timeout_ms, u32 max_reassemblies,
 997                u32 expire_walk_interval_ms)
 998 {
 999   u32 old_nbuckets = ip4_reass_get_nbuckets ();
1000   ip4_reass_main.timeout_ms = timeout_ms;
1001   ip4_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1002   ip4_reass_main.max_reass_n = max_reassemblies;
1003   ip4_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1004
1005   vlib_process_signal_event (ip4_reass_main.vlib_main,
1006                              ip4_reass_main.ip4_reass_expire_node_idx,
1007                              IP4_EVENT_CONFIG_CHANGED, 0);
1008   u32 new_nbuckets = ip4_reass_get_nbuckets ();
1009   if (ip4_reass_main.max_reass_n > 0 && new_nbuckets > 1 &&
1010       new_nbuckets != old_nbuckets)
1011     {
1012       clib_bihash_24_8_t new_hash;
1013       memset (&new_hash, 0, sizeof (new_hash));
1014       ip4_rehash_cb_ctx ctx;
1015       ctx.failure = 0;
1016       ctx.new_hash = &new_hash;
1017       clib_bihash_init_24_8 (&new_hash, "ip4-reass", new_nbuckets,
1018                              new_nbuckets * 1024);
1019       clib_bihash_foreach_key_value_pair_24_8 (&ip4_reass_main.hash,
1020                                                ip4_rehash_cb, &ctx);
1021       if (ctx.failure)
1022         {
1023           clib_bihash_free_24_8 (&new_hash);
1024           return -1;
1025         }
1026       else
1027         {
1028           clib_bihash_free_24_8 (&ip4_reass_main.hash);
1029           clib_memcpy (&ip4_reass_main.hash, &new_hash,
1030                        sizeof (ip4_reass_main.hash));
1031         }
1032     }
1033   return 0;
1034 }
1035
1036 vnet_api_error_t
1037 ip4_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1038                u32 * expire_walk_interval_ms)
1039 {
1040   *timeout_ms = ip4_reass_main.timeout_ms;
1041   *max_reassemblies = ip4_reass_main.max_reass_n;
1042   *expire_walk_interval_ms = ip4_reass_main.expire_walk_interval_ms;
1043   return 0;
1044 }
1045
1046 clib_error_t *
1047 ip4_reass_init_function (vlib_main_t * vm)
1048 {
1049   ip4_reass_main_t *rm = &ip4_reass_main;
1050   clib_error_t *error = 0;
1051   u32 nbuckets;
1052   vlib_node_t *node;
1053
1054   rm->vlib_main = vm;
1055   rm->vnet_main = vnet_get_main ();
1056
1057   rm->reass_n = 0;
1058   pool_alloc (rm->pool, rm->max_reass_n);
1059
1060   node = vlib_get_node_by_name (vm, (u8 *) "ip4-reassembly-expire-walk");
1061   ASSERT (node);
1062   rm->ip4_reass_expire_node_idx = node->index;
1063
1064   ip4_reass_set (IP4_REASS_TIMEOUT_DEFAULT_MS,
1065                  IP4_REASS_MAX_REASSEMBLIES_DEAFULT,
1066                  IP4_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1067
1068   nbuckets = ip4_reass_get_nbuckets ();
1069   clib_bihash_init_24_8 (&rm->hash, "ip4-reass", nbuckets, nbuckets * 1024);
1070
1071   node = vlib_get_node_by_name (vm, (u8 *) "ip4-drop");
1072   ASSERT (node);
1073   rm->ip4_drop_idx = node->index;
1074   return error;
1075 }
1076
1077 VLIB_INIT_FUNCTION (ip4_reass_init_function);
1078
1079 static uword
1080 ip4_reass_walk_expired (vlib_main_t * vm,
1081                         vlib_node_runtime_t * node, vlib_frame_t * f)
1082 {
1083   ip4_reass_main_t *rm = &ip4_reass_main;
1084   uword event_type, *event_data = 0;
1085
1086   while (true)
1087     {
1088       vlib_process_wait_for_event_or_clock (vm,
1089                                             (f64) rm->expire_walk_interval_ms
1090                                             / (f64) MSEC_PER_SEC);
1091       event_type = vlib_process_get_events (vm, &event_data);
1092
1093       switch (event_type)
1094         {
1095         case ~0:                /* no events => timeout */
1096           /* nothing to do here */
1097           break;
1098         case IP4_EVENT_CONFIG_CHANGED:
1099           break;
1100         default:
1101           clib_warning ("BUG: event type 0x%wx", event_type);
1102           break;
1103         }
1104       f64 now = vlib_time_now (vm);
1105
1106       ip4_reass_t *reass;
1107       u32 *vec_drop_timeout = NULL;
1108       int *pool_indexes_to_free = NULL;
1109
1110       int index;
1111       /* *INDENT-OFF* */
1112       pool_foreach_index (index, rm->pool, ({
1113                             reass = pool_elt_at_index (rm->pool, index);
1114                             if (now > reass->last_heard + rm->timeout)
1115                               {
1116                                 vec_add1 (pool_indexes_to_free, index);
1117                               }
1118                           }));
1119       /* *INDENT-ON* */
1120       int *i;
1121       /* *INDENT-OFF* */
1122       vec_foreach (i, pool_indexes_to_free)
1123       {
1124         ip4_reass_t *reass = pool_elt_at_index (rm->pool, i[0]);
1125         ip4_reass_on_timeout (vm, rm, reass, &vec_drop_timeout);
1126         ip4_reass_free (rm, reass);
1127       }
1128       /* *INDENT-ON* */
1129
1130       while (vec_len (vec_drop_timeout) > 0)
1131         {
1132           vlib_frame_t *f = vlib_get_frame_to_node (vm, rm->ip4_drop_idx);
1133           u32 *to_next = vlib_frame_vector_args (f);
1134           u32 n_left_to_next = VLIB_FRAME_SIZE - f->n_vectors;
1135           u32 n_trace = 0;
1136           while (vec_len (vec_drop_timeout) > 0 && n_left_to_next > 0)
1137             {
1138               u32 bi = vec_pop (vec_drop_timeout);
1139               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1140               if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1141                 {
1142                   if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1143                                           b->trace_index))
1144                     {
1145                       /* the trace is gone, don't trace this buffer anymore */
1146                       b->flags &= ~VLIB_BUFFER_IS_TRACED;
1147                     }
1148                   else
1149                     {
1150                       ++n_trace;
1151                     }
1152                 }
1153               b->error = node->errors[IP4_ERROR_REASS_TIMEOUT];
1154               to_next[0] = bi;
1155               ++f->n_vectors;
1156               to_next += 1;
1157               n_left_to_next -= 1;
1158               IP4_REASS_DEBUG_BUFFER (bi, enqueue_drop_timeout_walk);
1159               ASSERT (rm->buffers_n > 0);
1160               --rm->buffers_n;
1161             }
1162           if (PREDICT_FALSE (n_trace > 0))
1163             {
1164               f->flags |= VLIB_FRAME_TRACE;
1165             }
1166           vlib_put_frame_to_node (vm, rm->ip4_drop_idx, f);
1167         }
1168
1169       vec_free (pool_indexes_to_free);
1170       vec_free (vec_drop_timeout);
1171       if (event_data)
1172         {
1173           _vec_len (event_data) = 0;
1174         }
1175     }
1176
1177   return 0;
1178 }
1179
1180 static vlib_node_registration_t ip4_reass_expire_node;
1181
1182 /* *INDENT-OFF* */
1183 VLIB_REGISTER_NODE (ip4_reass_expire_node, static) = {
1184     .function = ip4_reass_walk_expired,
1185     .type = VLIB_NODE_TYPE_PROCESS,
1186     .name = "ip4-reassembly-expire-walk",
1187     .format_trace = format_ip4_reass_trace,
1188     .n_errors = ARRAY_LEN (ip4_reassembly_error_strings),
1189     .error_strings = ip4_reassembly_error_strings,
1190
1191 };
1192 /* *INDENT-ON* */
1193
1194 static u8 *
1195 format_ip4_reass_key (u8 * s, va_list * args)
1196 {
1197   ip4_reass_key_t *key = va_arg (*args, ip4_reass_key_t *);
1198   s = format (s, "xx_id: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1199               key->xx_id, format_ip4_address, &key->src, format_ip4_address,
1200               &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1201   return s;
1202 }
1203
1204 static u8 *
1205 format_ip4_reass (u8 * s, va_list * args)
1206 {
1207   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1208   ip4_reass_t *reass = va_arg (*args, ip4_reass_t *);
1209
1210   s = format (s, "ID: %u, key: %U\n  first_bi: %u, data_len: %u, "
1211               "last_packet_octet: %u, trace_op_counter: %u\n",
1212               reass->id, format_ip4_reass_key, &reass->key, reass->first_bi,
1213               reass->data_len, reass->last_packet_octet,
1214               reass->trace_op_counter);
1215   u32 bi = reass->first_bi;
1216   u32 counter = 0;
1217   while (~0 != bi)
1218     {
1219       vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1220       vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1221       s = format (s, "  #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1222                   "fragment[%u, %u]\n",
1223                   counter, vnb->ip.reass.range_first,
1224                   vnb->ip.reass.range_last, bi,
1225                   ip4_reass_buffer_get_data_offset_no_check (b),
1226                   ip4_reass_buffer_get_data_len_no_check (b),
1227                   vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1228       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1229         {
1230           bi = b->next_buffer;
1231         }
1232       else
1233         {
1234           bi = ~0;
1235         }
1236     }
1237   return s;
1238 }
1239
1240 static clib_error_t *
1241 show_ip4_reass (vlib_main_t * vm, unformat_input_t * input,
1242                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1243 {
1244   ip4_reass_main_t *rm = &ip4_reass_main;
1245
1246   vlib_cli_output (vm, "---------------------");
1247   vlib_cli_output (vm, "IP4 reassembly status");
1248   vlib_cli_output (vm, "---------------------");
1249   if (unformat (input, "details"))
1250     {
1251       ip4_reass_t *reass;
1252       /* *INDENT-OFF* */
1253       pool_foreach (reass, rm->pool, {
1254         vlib_cli_output (vm, "%U", format_ip4_reass, vm, reass);
1255       });
1256       /* *INDENT-ON* */
1257     }
1258   vlib_cli_output (vm, "---------------------");
1259   vlib_cli_output (vm, "Current IP4 reassemblies count: %lu\n", rm->reass_n);
1260   vlib_cli_output (vm,
1261                    "Maximum configured concurrent IP4 reassemblies: %lu\n",
1262                    (long unsigned) rm->max_reass_n);
1263   vlib_cli_output (vm, "Buffers in use: %lu\n",
1264                    (long unsigned) rm->buffers_n);
1265   return 0;
1266 }
1267
1268 /* *INDENT-OFF* */
1269 VLIB_CLI_COMMAND (show_ip4_reassembly_cmd, static) = {
1270     .path = "show ip4-reassembly",
1271     .short_help = "show ip4-reassembly [details]",
1272     .function = show_ip4_reass,
1273 };
1274 /* *INDENT-ON* */
1275
1276 /*
1277  * fd.io coding-style-patch-verification: ON
1278  *
1279  * Local Variables:
1280  * eval: (c-set-style "gnu")
1281  * End:
1282  */