src/vnet/ip/ip6_reassembly.c

   1 /*
   2  * Copyright (c) 2017 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 /**
  17  * @file
  18  * @brief IPv6 Reassembly.
  19  *
  20  * This file contains the source code for IPv6 reassembly.
  21  */
  22
  23 #include <vppinfra/vec.h>
  24 #include <vnet/vnet.h>
  25 #include <vnet/ip/ip.h>
  26 #include <vppinfra/bihash_48_8.h>
  27 #include <vnet/ip/ip6_reassembly.h>
  28
  29 #define MSEC_PER_SEC 1000
  30 #define IP6_REASS_TIMEOUT_DEFAULT_MS 100
  31 #define IP6_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS 10000 // 10 seconds default
  32 #define IP6_REASS_MAX_REASSEMBLIES_DEFAULT 1024
  33 #define IP6_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT 3
  34 #define IP6_REASS_HT_LOAD_FACTOR (0.75)
  35
  36 typedef enum
  37 {
  38   IP6_REASS_RC_OK,
  39   IP6_REASS_RC_INTERNAL_ERROR,
  40   IP6_REASS_RC_TOO_MANY_FRAGMENTS,
  41   IP6_REASS_RC_NO_BUF,
  42 } ip6_reass_rc_t;
  43
  44 typedef struct
  45 {
  46   union
  47   {
  48     struct
  49     {
  50       ip6_address_t src;
  51       ip6_address_t dst;
  52       u32 xx_id;
  53       u32 frag_id;
  54       u8 unused[7];
  55       u8 proto;
  56     };
  57     u64 as_u64[6];
  58   };
  59 } ip6_reass_key_t;
  60
  61 typedef union
  62 {
  63   struct
  64   {
  65     u32 reass_index;
  66     u32 thread_index;
  67   };
  68   u64 as_u64;
  69 } ip6_reass_val_t;
  70
  71 typedef union
  72 {
  73   struct
  74   {
  75     ip6_reass_key_t k;
  76     ip6_reass_val_t v;
  77   };
  78   clib_bihash_kv_48_8_t kv;
  79 } ip6_reass_kv_t;
  80
  81
  82 always_inline u32
  83 ip6_reass_buffer_get_data_offset (vlib_buffer_t * b)
  84 {
  85   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  86   return vnb->ip.reass.range_first - vnb->ip.reass.fragment_first;
  87 }
  88
  89 always_inline u16
  90 ip6_reass_buffer_get_data_len (vlib_buffer_t * b)
  91 {
  92   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  93   return clib_min (vnb->ip.reass.range_last, vnb->ip.reass.fragment_last) -
  94     (vnb->ip.reass.fragment_first + ip6_reass_buffer_get_data_offset (b)) + 1;
  95 }
  96
  97 typedef struct
  98 {
  99   // hash table key
 100   ip6_reass_key_t key;
 101   // time when last packet was received
 102   f64 last_heard;
 103   // internal id of this reassembly
 104   u64 id;
 105   // buffer index of first buffer in this reassembly context
 106   u32 first_bi;
 107   // last octet of packet, ~0 until fragment without more_fragments arrives
 108   u32 last_packet_octet;
 109   // length of data collected so far
 110   u32 data_len;
 111   // trace operation counter
 112   u32 trace_op_counter;
 113   // next index - used by non-feature node
 114   u8 next_index;
 115   // minimum fragment length for this reassembly - used to estimate MTU
 116   u16 min_fragment_length;
 117   // number of fragments for this reassembly
 118   u32 fragments_n;
 119 } ip6_reass_t;
 120
 121 typedef struct
 122 {
 123   ip6_reass_t *pool;
 124   u32 reass_n;
 125   u32 id_counter;
 126   clib_spinlock_t lock;
 127 } ip6_reass_per_thread_t;
 128
 129 typedef struct
 130 {
 131   // IPv6 config
 132   u32 timeout_ms;
 133   f64 timeout;
 134   u32 expire_walk_interval_ms;
 135   // maximum number of fragments in one reassembly
 136   u32 max_reass_len;
 137   // maximum number of reassemblies
 138   u32 max_reass_n;
 139
 140   // IPv6 runtime
 141   clib_bihash_48_8_t hash;
 142
 143   // per-thread data
 144   ip6_reass_per_thread_t *per_thread_data;
 145
 146   // convenience
 147   vlib_main_t *vlib_main;
 148   vnet_main_t *vnet_main;
 149
 150   // node index of ip6-drop node
 151   u32 ip6_drop_idx;
 152   u32 ip6_icmp_error_idx;
 153   u32 ip6_reass_expire_node_idx;
 154
 155   /** Worker handoff */
 156   u32 fq_index;
 157   u32 fq_feature_index;
 158
 159 } ip6_reass_main_t;
 160
 161 extern ip6_reass_main_t ip6_reass_main;
 162
 163 #ifndef CLIB_MARCH_VARIANT
 164 ip6_reass_main_t ip6_reass_main;
 165 #endif /* CLIB_MARCH_VARIANT */
 166
 167 typedef enum
 168 {
 169   IP6_REASSEMBLY_NEXT_INPUT,
 170   IP6_REASSEMBLY_NEXT_DROP,
 171   IP6_REASSEMBLY_NEXT_ICMP_ERROR,
 172   IP6_REASSEMBLY_NEXT_HANDOFF,
 173   IP6_REASSEMBLY_N_NEXT,
 174 } ip6_reass_next_t;
 175
 176 typedef enum
 177 {
 178   RANGE_NEW,
 179   RANGE_OVERLAP,
 180   ICMP_ERROR_RT_EXCEEDED,
 181   ICMP_ERROR_FL_TOO_BIG,
 182   ICMP_ERROR_FL_NOT_MULT_8,
 183   FINALIZE,
 184 } ip6_reass_trace_operation_e;
 185
 186 typedef struct
 187 {
 188   u16 range_first;
 189   u16 range_last;
 190   u32 range_bi;
 191   i32 data_offset;
 192   u32 data_len;
 193   u32 first_bi;
 194 } ip6_reass_range_trace_t;
 195
 196 typedef struct
 197 {
 198   ip6_reass_trace_operation_e action;
 199   u32 reass_id;
 200   ip6_reass_range_trace_t trace_range;
 201   u32 size_diff;
 202   u32 op_id;
 203   u32 fragment_first;
 204   u32 fragment_last;
 205   u32 total_data_len;
 206 } ip6_reass_trace_t;
 207
 208 static void
 209 ip6_reass_trace_details (vlib_main_t * vm, u32 bi,
 210                          ip6_reass_range_trace_t * trace)
 211 {
 212   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 213   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 214   trace->range_first = vnb->ip.reass.range_first;
 215   trace->range_last = vnb->ip.reass.range_last;
 216   trace->data_offset = ip6_reass_buffer_get_data_offset (b);
 217   trace->data_len = ip6_reass_buffer_get_data_len (b);
 218   trace->range_bi = bi;
 219 }
 220
 221 static u8 *
 222 format_ip6_reass_range_trace (u8 * s, va_list * args)
 223 {
 224   ip6_reass_range_trace_t *trace = va_arg (*args, ip6_reass_range_trace_t *);
 225   s = format (s, "range: [%u, %u], off %d, len %u, bi %u", trace->range_first,
 226               trace->range_last, trace->data_offset, trace->data_len,
 227               trace->range_bi);
 228   return s;
 229 }
 230
 231 static u8 *
 232 format_ip6_reass_trace (u8 * s, va_list * args)
 233 {
 234   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
 235   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
 236   ip6_reass_trace_t *t = va_arg (*args, ip6_reass_trace_t *);
 237   s = format (s, "reass id: %u, op id: %u ", t->reass_id, t->op_id);
 238   u32 indent = format_get_indent (s);
 239   s = format (s, "first bi: %u, data len: %u, ip/fragment[%u, %u]",
 240               t->trace_range.first_bi, t->total_data_len, t->fragment_first,
 241               t->fragment_last);
 242   switch (t->action)
 243     {
 244     case RANGE_NEW:
 245       s = format (s, "\n%Unew %U", format_white_space, indent,
 246                   format_ip6_reass_range_trace, &t->trace_range);
 247       break;
 248     case RANGE_OVERLAP:
 249       s = format (s, "\n%Uoverlap %U", format_white_space, indent,
 250                   format_ip6_reass_range_trace, &t->trace_range);
 251       break;
 252     case ICMP_ERROR_FL_TOO_BIG:
 253       s = format (s, "\n%Uicmp-error - frag_len > 65535 %U",
 254                   format_white_space, indent, format_ip6_reass_range_trace,
 255                   &t->trace_range);
 256       break;
 257     case ICMP_ERROR_FL_NOT_MULT_8:
 258       s = format (s, "\n%Uicmp-error - frag_len mod 8 != 0 %U",
 259                   format_white_space, indent, format_ip6_reass_range_trace,
 260                   &t->trace_range);
 261       break;
 262     case ICMP_ERROR_RT_EXCEEDED:
 263       s = format (s, "\n%Uicmp-error - reassembly time exceeded",
 264                   format_white_space, indent);
 265       break;
 266     case FINALIZE:
 267       s = format (s, "\n%Ufinalize reassembly", format_white_space, indent);
 268       break;
 269     }
 270   return s;
 271 }
 272
 273 static void
 274 ip6_reass_add_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
 275                      ip6_reass_main_t * rm, ip6_reass_t * reass,
 276                      u32 bi, ip6_reass_trace_operation_e action,
 277                      u32 size_diff)
 278 {
 279   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 280   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 281   if (pool_is_free_index (vm->trace_main.trace_buffer_pool, b->trace_index))
 282     {
 283       // this buffer's trace is gone
 284       b->flags &= ~VLIB_BUFFER_IS_TRACED;
 285       return;
 286     }
 287   ip6_reass_trace_t *t = vlib_add_trace (vm, node, b, sizeof (t[0]));
 288   t->reass_id = reass->id;
 289   t->action = action;
 290   ip6_reass_trace_details (vm, bi, &t->trace_range);
 291   t->size_diff = size_diff;
 292   t->op_id = reass->trace_op_counter;
 293   ++reass->trace_op_counter;
 294   t->fragment_first = vnb->ip.reass.fragment_first;
 295   t->fragment_last = vnb->ip.reass.fragment_last;
 296   t->trace_range.first_bi = reass->first_bi;
 297   t->total_data_len = reass->data_len;
 298 #if 0
 299   static u8 *s = NULL;
 300   s = format (s, "%U", format_ip6_reass_trace, NULL, NULL, t);
 301   printf ("%.*s\n", vec_len (s), s);
 302   fflush (stdout);
 303   vec_reset_length (s);
 304 #endif
 305 }
 306
 307 always_inline void
 308 ip6_reass_free (ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 309                 ip6_reass_t * reass)
 310 {
 311   clib_bihash_kv_48_8_t kv;
 312   kv.key[0] = reass->key.as_u64[0];
 313   kv.key[1] = reass->key.as_u64[1];
 314   kv.key[2] = reass->key.as_u64[2];
 315   kv.key[3] = reass->key.as_u64[3];
 316   kv.key[4] = reass->key.as_u64[4];
 317   kv.key[5] = reass->key.as_u64[5];
 318   clib_bihash_add_del_48_8 (&rm->hash, &kv, 0);
 319   pool_put (rt->pool, reass);
 320   --rt->reass_n;
 321 }
 322
 323 always_inline void
 324 ip6_reass_drop_all (vlib_main_t * vm, ip6_reass_main_t * rm,
 325                     ip6_reass_t * reass)
 326 {
 327   u32 range_bi = reass->first_bi;
 328   vlib_buffer_t *range_b;
 329   vnet_buffer_opaque_t *range_vnb;
 330   u32 *to_free = NULL;
 331   while (~0 != range_bi)
 332     {
 333       range_b = vlib_get_buffer (vm, range_bi);
 334       range_vnb = vnet_buffer (range_b);
 335       u32 bi = range_bi;
 336       while (~0 != bi)
 337         {
 338           vec_add1 (to_free, bi);
 339           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 340           if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 341             {
 342               bi = b->next_buffer;
 343               b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 344             }
 345           else
 346             {
 347               bi = ~0;
 348             }
 349         }
 350       range_bi = range_vnb->ip.reass.next_range_bi;
 351     }
 352   vlib_buffer_free (vm, to_free, vec_len (to_free));
 353   vec_free (to_free);
 354 }
 355
 356 always_inline void
 357 ip6_reass_on_timeout (vlib_main_t * vm, vlib_node_runtime_t * node,
 358                       ip6_reass_main_t * rm, ip6_reass_t * reass,
 359                       u32 * icmp_bi)
 360 {
 361   if (~0 == reass->first_bi)
 362     {
 363       return;
 364     }
 365   vlib_buffer_t *b = vlib_get_buffer (vm, reass->first_bi);
 366   if (0 == vnet_buffer (b)->ip.reass.fragment_first)
 367     {
 368       *icmp_bi = reass->first_bi;
 369       if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
 370         {
 371           ip6_reass_add_trace (vm, node, rm, reass, reass->first_bi,
 372                                ICMP_ERROR_RT_EXCEEDED, 0);
 373         }
 374       // fragment with offset zero received - send icmp message back
 375       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 376         {
 377           // separate first buffer from chain and steer it towards icmp node
 378           b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 379           reass->first_bi = b->next_buffer;
 380         }
 381       else
 382         {
 383           reass->first_bi = vnet_buffer (b)->ip.reass.next_range_bi;
 384         }
 385       icmp6_error_set_vnet_buffer (b, ICMP6_time_exceeded,
 386                                    ICMP6_time_exceeded_fragment_reassembly_time_exceeded,
 387                                    0);
 388     }
 389   ip6_reass_drop_all (vm, rm, reass);
 390 }
 391
 392 always_inline ip6_reass_t *
 393 ip6_reass_find_or_create (vlib_main_t * vm, vlib_node_runtime_t * node,
 394                           ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 395                           ip6_reass_kv_t * kv, u32 * icmp_bi, u8 * do_handoff)
 396 {
 397   ip6_reass_t *reass = NULL;
 398   f64 now = vlib_time_now (rm->vlib_main);
 399
 400   if (!clib_bihash_search_48_8
 401       (&rm->hash, (clib_bihash_kv_48_8_t *) kv, (clib_bihash_kv_48_8_t *) kv))
 402     {
 403       if (vm->thread_index != kv->v.thread_index)
 404         {
 405           *do_handoff = 1;
 406           return NULL;
 407         }
 408       reass = pool_elt_at_index (rt->pool, kv->v.reass_index);
 409
 410       if (now > reass->last_heard + rm->timeout)
 411         {
 412           ip6_reass_on_timeout (vm, node, rm, reass, icmp_bi);
 413           ip6_reass_free (rm, rt, reass);
 414           reass = NULL;
 415         }
 416     }
 417
 418   if (reass)
 419     {
 420       reass->last_heard = now;
 421       return reass;
 422     }
 423
 424   if (rt->reass_n >= rm->max_reass_n)
 425     {
 426       reass = NULL;
 427       return reass;
 428     }
 429   else
 430     {
 431       pool_get (rt->pool, reass);
 432       clib_memset (reass, 0, sizeof (*reass));
 433       reass->id = ((u64) vm->thread_index * 1000000000) + rt->id_counter;
 434       ++rt->id_counter;
 435       reass->first_bi = ~0;
 436       reass->last_packet_octet = ~0;
 437       reass->data_len = 0;
 438       ++rt->reass_n;
 439     }
 440
 441   reass->key.as_u64[0] = ((clib_bihash_kv_48_8_t *) kv)->key[0];
 442   reass->key.as_u64[1] = ((clib_bihash_kv_48_8_t *) kv)->key[1];
 443   reass->key.as_u64[2] = ((clib_bihash_kv_48_8_t *) kv)->key[2];
 444   reass->key.as_u64[3] = ((clib_bihash_kv_48_8_t *) kv)->key[3];
 445   reass->key.as_u64[4] = ((clib_bihash_kv_48_8_t *) kv)->key[4];
 446   reass->key.as_u64[5] = ((clib_bihash_kv_48_8_t *) kv)->key[5];
 447   kv->v.reass_index = (reass - rt->pool);
 448   kv->v.thread_index = vm->thread_index;
 449   reass->last_heard = now;
 450
 451   if (clib_bihash_add_del_48_8 (&rm->hash, (clib_bihash_kv_48_8_t *) kv, 1))
 452     {
 453       ip6_reass_free (rm, rt, reass);
 454       reass = NULL;
 455     }
 456
 457   return reass;
 458 }
 459
 460 always_inline ip6_reass_rc_t
 461 ip6_reass_finalize (vlib_main_t * vm, vlib_node_runtime_t * node,
 462                     ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 463                     ip6_reass_t * reass, u32 * bi0, u32 * next0, u32 * error0,
 464                     bool is_feature)
 465 {
 466   *bi0 = reass->first_bi;
 467   *error0 = IP6_ERROR_NONE;
 468   ip6_frag_hdr_t *frag_hdr;
 469   vlib_buffer_t *last_b = NULL;
 470   u32 sub_chain_bi = reass->first_bi;
 471   u32 total_length = 0;
 472   u32 buf_cnt = 0;
 473   u32 dropped_cnt = 0;
 474   u32 *vec_drop_compress = NULL;
 475   ip6_reass_rc_t rv = IP6_REASS_RC_OK;
 476   do
 477     {
 478       u32 tmp_bi = sub_chain_bi;
 479       vlib_buffer_t *tmp = vlib_get_buffer (vm, tmp_bi);
 480       vnet_buffer_opaque_t *vnb = vnet_buffer (tmp);
 481       if (!(vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first) &&
 482           !(vnb->ip.reass.range_last > vnb->ip.reass.fragment_first))
 483         {
 484           rv = IP6_REASS_RC_INTERNAL_ERROR;
 485           goto free_buffers_and_return;
 486         }
 487
 488       u32 data_len = ip6_reass_buffer_get_data_len (tmp);
 489       u32 trim_front = vnet_buffer (tmp)->ip.reass.ip6_frag_hdr_offset +
 490         sizeof (*frag_hdr) + ip6_reass_buffer_get_data_offset (tmp);
 491       u32 trim_end =
 492         vlib_buffer_length_in_chain (vm, tmp) - trim_front - data_len;
 493       if (tmp_bi == reass->first_bi)
 494         {
 495           /* first buffer - keep ip6 header */
 496           if (0 != ip6_reass_buffer_get_data_offset (tmp))
 497             {
 498               rv = IP6_REASS_RC_INTERNAL_ERROR;
 499               goto free_buffers_and_return;
 500             }
 501           trim_front = 0;
 502           trim_end = vlib_buffer_length_in_chain (vm, tmp) - data_len -
 503             (vnet_buffer (tmp)->ip.reass.ip6_frag_hdr_offset +
 504              sizeof (*frag_hdr));
 505           if (!(vlib_buffer_length_in_chain (vm, tmp) - trim_end > 0))
 506             {
 507               rv = IP6_REASS_RC_INTERNAL_ERROR;
 508               goto free_buffers_and_return;
 509             }
 510         }
 511       u32 keep_data =
 512         vlib_buffer_length_in_chain (vm, tmp) - trim_front - trim_end;
 513       while (1)
 514         {
 515           ++buf_cnt;
 516           if (trim_front)
 517             {
 518               if (trim_front > tmp->current_length)
 519                 {
 520                   /* drop whole buffer */
 521                   vec_add1 (vec_drop_compress, tmp_bi);
 522                   trim_front -= tmp->current_length;
 523                   if (!(tmp->flags & VLIB_BUFFER_NEXT_PRESENT))
 524                     {
 525                       rv = IP6_REASS_RC_INTERNAL_ERROR;
 526                       goto free_buffers_and_return;
 527                     }
 528                   tmp->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 529                   tmp_bi = tmp->next_buffer;
 530                   tmp = vlib_get_buffer (vm, tmp_bi);
 531                   continue;
 532                 }
 533               else
 534                 {
 535                   vlib_buffer_advance (tmp, trim_front);
 536                   trim_front = 0;
 537                 }
 538             }
 539           if (keep_data)
 540             {
 541               if (last_b)
 542                 {
 543                   last_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
 544                   last_b->next_buffer = tmp_bi;
 545                 }
 546               last_b = tmp;
 547               if (keep_data <= tmp->current_length)
 548                 {
 549                   tmp->current_length = keep_data;
 550                   keep_data = 0;
 551                 }
 552               else
 553                 {
 554                   keep_data -= tmp->current_length;
 555                   if (!(tmp->flags & VLIB_BUFFER_NEXT_PRESENT))
 556                     {
 557                       rv = IP6_REASS_RC_INTERNAL_ERROR;
 558                       goto free_buffers_and_return;
 559                     }
 560                 }
 561               total_length += tmp->current_length;
 562             }
 563           else
 564             {
 565               vec_add1 (vec_drop_compress, tmp_bi);
 566               if (reass->first_bi == tmp_bi)
 567                 {
 568                   rv = IP6_REASS_RC_INTERNAL_ERROR;
 569                   goto free_buffers_and_return;
 570                 }
 571               ++dropped_cnt;
 572             }
 573           if (tmp->flags & VLIB_BUFFER_NEXT_PRESENT)
 574             {
 575               tmp_bi = tmp->next_buffer;
 576               tmp = vlib_get_buffer (vm, tmp->next_buffer);
 577             }
 578           else
 579             {
 580               break;
 581             }
 582         }
 583       sub_chain_bi =
 584         vnet_buffer (vlib_get_buffer (vm, sub_chain_bi))->ip.
 585         reass.next_range_bi;
 586     }
 587   while (~0 != sub_chain_bi);
 588
 589   if (!last_b)
 590     {
 591       rv = IP6_REASS_RC_INTERNAL_ERROR;
 592       goto free_buffers_and_return;
 593     }
 594   last_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 595   vlib_buffer_t *first_b = vlib_get_buffer (vm, reass->first_bi);
 596   if (total_length < first_b->current_length)
 597     {
 598       rv = IP6_REASS_RC_INTERNAL_ERROR;
 599       goto free_buffers_and_return;
 600     }
 601   total_length -= first_b->current_length;
 602   first_b->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
 603   first_b->total_length_not_including_first_buffer = total_length;
 604   // drop fragment header
 605   vnet_buffer_opaque_t *first_b_vnb = vnet_buffer (first_b);
 606   ip6_header_t *ip = vlib_buffer_get_current (first_b);
 607   u16 ip6_frag_hdr_offset = first_b_vnb->ip.reass.ip6_frag_hdr_offset;
 608   ip6_ext_header_t *prev_hdr;
 609   ip6_ext_header_find_t (ip, prev_hdr, frag_hdr,
 610                          IP_PROTOCOL_IPV6_FRAGMENTATION);
 611   if (prev_hdr)
 612     {
 613       prev_hdr->next_hdr = frag_hdr->next_hdr;
 614     }
 615   else
 616     {
 617       ip->protocol = frag_hdr->next_hdr;
 618     }
 619   if (!((u8 *) frag_hdr - (u8 *) ip == ip6_frag_hdr_offset))
 620     {
 621       rv = IP6_REASS_RC_INTERNAL_ERROR;
 622       goto free_buffers_and_return;
 623     }
 624   memmove (frag_hdr, (u8 *) frag_hdr + sizeof (*frag_hdr),
 625            first_b->current_length - ip6_frag_hdr_offset -
 626            sizeof (ip6_frag_hdr_t));
 627   first_b->current_length -= sizeof (*frag_hdr);
 628   ip->payload_length =
 629     clib_host_to_net_u16 (total_length + first_b->current_length -
 630                           sizeof (*ip));
 631   if (!vlib_buffer_chain_linearize (vm, first_b))
 632     {
 633       rv = IP6_REASS_RC_NO_BUF;
 634       goto free_buffers_and_return;
 635     }
 636   if (PREDICT_FALSE (first_b->flags & VLIB_BUFFER_IS_TRACED))
 637     {
 638       ip6_reass_add_trace (vm, node, rm, reass, reass->first_bi, FINALIZE, 0);
 639 #if 0
 640       // following code does a hexdump of packet fragments to stdout ...
 641       do
 642         {
 643           u32 bi = reass->first_bi;
 644           u8 *s = NULL;
 645           while (~0 != bi)
 646             {
 647               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 648               s = format (s, "%u: %U\n", bi, format_hexdump,
 649                           vlib_buffer_get_current (b), b->current_length);
 650               if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 651                 {
 652                   bi = b->next_buffer;
 653                 }
 654               else
 655                 {
 656                   break;
 657                 }
 658             }
 659           printf ("%.*s\n", vec_len (s), s);
 660           fflush (stdout);
 661           vec_free (s);
 662         }
 663       while (0);
 664 #endif
 665     }
 666   if (is_feature)
 667     {
 668       *next0 = IP6_REASSEMBLY_NEXT_INPUT;
 669     }
 670   else
 671     {
 672       *next0 = reass->next_index;
 673     }
 674   vnet_buffer (first_b)->ip.reass.estimated_mtu = reass->min_fragment_length;
 675   ip6_reass_free (rm, rt, reass);
 676   reass = NULL;
 677 free_buffers_and_return:
 678   vlib_buffer_free (vm, vec_drop_compress, vec_len (vec_drop_compress));
 679   vec_free (vec_drop_compress);
 680   return rv;
 681 }
 682
 683 always_inline void
 684 ip6_reass_insert_range_in_chain (vlib_main_t * vm, ip6_reass_main_t * rm,
 685                                  ip6_reass_per_thread_t * rt,
 686                                  ip6_reass_t * reass, u32 prev_range_bi,
 687                                  u32 new_next_bi)
 688 {
 689
 690   vlib_buffer_t *new_next_b = vlib_get_buffer (vm, new_next_bi);
 691   vnet_buffer_opaque_t *new_next_vnb = vnet_buffer (new_next_b);
 692   if (~0 != prev_range_bi)
 693     {
 694       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
 695       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
 696       new_next_vnb->ip.reass.next_range_bi = prev_vnb->ip.reass.next_range_bi;
 697       prev_vnb->ip.reass.next_range_bi = new_next_bi;
 698     }
 699   else
 700     {
 701       if (~0 != reass->first_bi)
 702         {
 703           new_next_vnb->ip.reass.next_range_bi = reass->first_bi;
 704         }
 705       reass->first_bi = new_next_bi;
 706     }
 707   reass->data_len += ip6_reass_buffer_get_data_len (new_next_b);
 708 }
 709
 710 always_inline ip6_reass_rc_t
 711 ip6_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
 712                   ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 713                   ip6_reass_t * reass, u32 * bi0, u32 * next0, u32 * error0,
 714                   ip6_frag_hdr_t * frag_hdr, bool is_feature)
 715 {
 716   int consumed = 0;
 717   vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
 718   vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
 719   reass->next_index = fvnb->ip.reass.next_index;        // store next_index before it's overwritten
 720   fvnb->ip.reass.ip6_frag_hdr_offset =
 721     (u8 *) frag_hdr - (u8 *) vlib_buffer_get_current (fb);
 722   ip6_header_t *fip = vlib_buffer_get_current (fb);
 723   if (fb->current_length < sizeof (*fip) ||
 724       fvnb->ip.reass.ip6_frag_hdr_offset == 0 ||
 725       fvnb->ip.reass.ip6_frag_hdr_offset >= fb->current_length)
 726     {
 727       return IP6_REASS_RC_INTERNAL_ERROR;
 728     }
 729
 730   u32 fragment_first = fvnb->ip.reass.fragment_first =
 731     ip6_frag_hdr_offset_bytes (frag_hdr);
 732   u32 fragment_length =
 733     vlib_buffer_length_in_chain (vm, fb) -
 734     (fvnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 735   u32 fragment_last = fvnb->ip.reass.fragment_last =
 736     fragment_first + fragment_length - 1;
 737   int more_fragments = ip6_frag_hdr_more (frag_hdr);
 738   u32 candidate_range_bi = reass->first_bi;
 739   u32 prev_range_bi = ~0;
 740   fvnb->ip.reass.range_first = fragment_first;
 741   fvnb->ip.reass.range_last = fragment_last;
 742   fvnb->ip.reass.next_range_bi = ~0;
 743   if (!more_fragments)
 744     {
 745       reass->last_packet_octet = fragment_last;
 746     }
 747   if (~0 == reass->first_bi)
 748     {
 749       // starting a new reassembly
 750       ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
 751                                        *bi0);
 752       reass->min_fragment_length = clib_net_to_host_u16 (fip->payload_length);
 753       consumed = 1;
 754       reass->fragments_n = 1;
 755       goto check_if_done_maybe;
 756     }
 757   reass->min_fragment_length =
 758     clib_min (clib_net_to_host_u16 (fip->payload_length),
 759               fvnb->ip.reass.estimated_mtu);
 760   while (~0 != candidate_range_bi)
 761     {
 762       vlib_buffer_t *candidate_b = vlib_get_buffer (vm, candidate_range_bi);
 763       vnet_buffer_opaque_t *candidate_vnb = vnet_buffer (candidate_b);
 764       if (fragment_first > candidate_vnb->ip.reass.range_last)
 765         {
 766           // this fragments starts after candidate range
 767           prev_range_bi = candidate_range_bi;
 768           candidate_range_bi = candidate_vnb->ip.reass.next_range_bi;
 769           if (candidate_vnb->ip.reass.range_last < fragment_last &&
 770               ~0 == candidate_range_bi)
 771             {
 772               // special case - this fragment falls beyond all known ranges
 773               ip6_reass_insert_range_in_chain (vm, rm, rt, reass,
 774                                                prev_range_bi, *bi0);
 775               consumed = 1;
 776               break;
 777             }
 778           continue;
 779         }
 780       if (fragment_last < candidate_vnb->ip.reass.range_first)
 781         {
 782           // this fragment ends before candidate range without any overlap
 783           ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
 784                                            *bi0);
 785           consumed = 1;
 786         }
 787       else if (fragment_first == candidate_vnb->ip.reass.range_first &&
 788                fragment_last == candidate_vnb->ip.reass.range_last)
 789         {
 790           // duplicate fragment - ignore
 791         }
 792       else
 793         {
 794           // overlapping fragment - not allowed by RFC 8200
 795           ip6_reass_drop_all (vm, rm, reass);
 796           ip6_reass_free (rm, rt, reass);
 797           if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 798             {
 799               ip6_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_OVERLAP,
 800                                    0);
 801             }
 802           *next0 = IP6_REASSEMBLY_NEXT_DROP;
 803           *error0 = IP6_ERROR_REASS_OVERLAPPING_FRAGMENT;
 804           return IP6_REASS_RC_OK;
 805         }
 806       break;
 807     }
 808   ++reass->fragments_n;
 809 check_if_done_maybe:
 810   if (consumed)
 811     {
 812       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 813         {
 814           ip6_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
 815         }
 816     }
 817   if (~0 != reass->last_packet_octet &&
 818       reass->data_len == reass->last_packet_octet + 1)
 819     {
 820       return ip6_reass_finalize (vm, node, rm, rt, reass, bi0, next0, error0,
 821                                  is_feature);
 822     }
 823   else
 824     {
 825       if (consumed)
 826         {
 827           *bi0 = ~0;
 828           if (reass->fragments_n > rm->max_reass_len)
 829             {
 830               return IP6_REASS_RC_TOO_MANY_FRAGMENTS;
 831             }
 832         }
 833       else
 834         {
 835           *next0 = IP6_REASSEMBLY_NEXT_DROP;
 836           *error0 = IP6_ERROR_REASS_DUPLICATE_FRAGMENT;
 837         }
 838     }
 839   return IP6_REASS_RC_OK;
 840 }
 841
 842 always_inline bool
 843 ip6_reass_verify_upper_layer_present (vlib_node_runtime_t * node,
 844                                       vlib_buffer_t * b,
 845                                       ip6_frag_hdr_t * frag_hdr)
 846 {
 847   ip6_ext_header_t *tmp = (ip6_ext_header_t *) frag_hdr;
 848   while (ip6_ext_hdr (tmp->next_hdr))
 849     {
 850       tmp = ip6_ext_next_header (tmp);
 851     }
 852   if (IP_PROTOCOL_IP6_NONXT == tmp->next_hdr)
 853     {
 854       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 855                                    ICMP6_parameter_problem_first_fragment_has_incomplete_header_chain,
 856                                    0);
 857       b->error = node->errors[IP6_ERROR_REASS_MISSING_UPPER];
 858
 859       return false;
 860     }
 861   return true;
 862 }
 863
 864 always_inline bool
 865 ip6_reass_verify_fragment_multiple_8 (vlib_main_t * vm,
 866                                       vlib_node_runtime_t * node,
 867                                       vlib_buffer_t * b,
 868                                       ip6_frag_hdr_t * frag_hdr)
 869 {
 870   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 871   ip6_header_t *ip = vlib_buffer_get_current (b);
 872   int more_fragments = ip6_frag_hdr_more (frag_hdr);
 873   u32 fragment_length =
 874     vlib_buffer_length_in_chain (vm, b) -
 875     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 876   if (more_fragments && 0 != fragment_length % 8)
 877     {
 878       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 879                                    ICMP6_parameter_problem_erroneous_header_field,
 880                                    (u8 *) & ip->payload_length - (u8 *) ip);
 881       return false;
 882     }
 883   return true;
 884 }
 885
 886 always_inline bool
 887 ip6_reass_verify_packet_size_lt_64k (vlib_main_t * vm,
 888                                      vlib_node_runtime_t * node,
 889                                      vlib_buffer_t * b,
 890                                      ip6_frag_hdr_t * frag_hdr)
 891 {
 892   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 893   u32 fragment_first = ip6_frag_hdr_offset_bytes (frag_hdr);
 894   u32 fragment_length =
 895     vlib_buffer_length_in_chain (vm, b) -
 896     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 897   if (fragment_first + fragment_length > 65535)
 898     {
 899       ip6_header_t *ip0 = vlib_buffer_get_current (b);
 900       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 901                                    ICMP6_parameter_problem_erroneous_header_field,
 902                                    (u8 *) & frag_hdr->fragment_offset_and_more
 903                                    - (u8 *) ip0);
 904       return false;
 905     }
 906   return true;
 907 }
 908
 909 always_inline uword
 910 ip6_reassembly_inline (vlib_main_t * vm,
 911                        vlib_node_runtime_t * node,
 912                        vlib_frame_t * frame, bool is_feature)
 913 {
 914   u32 *from = vlib_frame_vector_args (frame);
 915   u32 n_left_from, n_left_to_next, *to_next, next_index;
 916   ip6_reass_main_t *rm = &ip6_reass_main;
 917   ip6_reass_per_thread_t *rt = &rm->per_thread_data[vm->thread_index];
 918   clib_spinlock_lock (&rt->lock);
 919
 920   n_left_from = frame->n_vectors;
 921   next_index = node->cached_next_index;
 922   while (n_left_from > 0)
 923     {
 924       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 925
 926       while (n_left_from > 0 && n_left_to_next > 0)
 927         {
 928           u32 bi0;
 929           vlib_buffer_t *b0;
 930           u32 next0 = IP6_REASSEMBLY_NEXT_DROP;
 931           u32 error0 = IP6_ERROR_NONE;
 932           u32 icmp_bi = ~0;
 933
 934           bi0 = from[0];
 935           b0 = vlib_get_buffer (vm, bi0);
 936
 937           ip6_header_t *ip0 = vlib_buffer_get_current (b0);
 938           ip6_frag_hdr_t *frag_hdr = NULL;
 939           ip6_ext_header_t *prev_hdr;
 940           if (ip6_ext_hdr (ip0->protocol))
 941             {
 942               ip6_ext_header_find_t (ip0, prev_hdr, frag_hdr,
 943                                      IP_PROTOCOL_IPV6_FRAGMENTATION);
 944             }
 945           if (!frag_hdr)
 946             {
 947               // this is a regular packet - no fragmentation
 948               next0 = IP6_REASSEMBLY_NEXT_INPUT;
 949               goto skip_reass;
 950             }
 951           if (0 == ip6_frag_hdr_offset (frag_hdr))
 952             {
 953               // first fragment - verify upper-layer is present
 954               if (!ip6_reass_verify_upper_layer_present (node, b0, frag_hdr))
 955                 {
 956                   next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
 957                   goto skip_reass;
 958                 }
 959             }
 960           if (!ip6_reass_verify_fragment_multiple_8 (vm, node, b0, frag_hdr)
 961               || !ip6_reass_verify_packet_size_lt_64k (vm, node, b0,
 962                                                        frag_hdr))
 963             {
 964               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
 965               goto skip_reass;
 966             }
 967           vnet_buffer (b0)->ip.reass.ip6_frag_hdr_offset =
 968             (u8 *) frag_hdr - (u8 *) ip0;
 969
 970           ip6_reass_kv_t kv;
 971           u8 do_handoff = 0;
 972
 973           kv.k.as_u64[0] = ip0->src_address.as_u64[0];
 974           kv.k.as_u64[1] = ip0->src_address.as_u64[1];
 975           kv.k.as_u64[2] = ip0->dst_address.as_u64[0];
 976           kv.k.as_u64[3] = ip0->dst_address.as_u64[1];
 977           kv.k.as_u64[4] =
 978             ((u64) vec_elt (ip6_main.fib_index_by_sw_if_index,
 979                             vnet_buffer (b0)->sw_if_index[VLIB_RX])) << 32 |
 980             (u64) frag_hdr->identification;
 981           kv.k.as_u64[5] = ip0->protocol;
 982
 983           ip6_reass_t *reass =
 984             ip6_reass_find_or_create (vm, node, rm, rt, &kv, &icmp_bi,
 985                                       &do_handoff);
 986
 987           if (PREDICT_FALSE (do_handoff))
 988             {
 989               next0 = IP6_REASSEMBLY_NEXT_HANDOFF;
 990               if (is_feature)
 991                 vnet_buffer (b0)->ip.reass.owner_feature_thread_index =
 992                   kv.v.thread_index;
 993               else
 994                 vnet_buffer (b0)->ip.reass.owner_thread_index =
 995                   kv.v.thread_index;
 996             }
 997           else if (reass)
 998             {
 999               switch (ip6_reass_update (vm, node, rm, rt, reass, &bi0, &next0,
1000                                         &error0, frag_hdr, is_feature))
1001                 {
1002                 case IP6_REASS_RC_OK:
1003                   /* nothing to do here */
1004                   break;
1005                 case IP6_REASS_RC_TOO_MANY_FRAGMENTS:
1006                   vlib_node_increment_counter (vm, node->node_index,
1007                                                IP6_ERROR_REASS_FRAGMENT_CHAIN_TOO_LONG,
1008                                                1);
1009                   ip6_reass_drop_all (vm, rm, reass);
1010                   ip6_reass_free (rm, rt, reass);
1011                   goto next_packet;
1012                   break;
1013                 case IP6_REASS_RC_NO_BUF:
1014                   vlib_node_increment_counter (vm, node->node_index,
1015                                                IP6_ERROR_REASS_NO_BUF, 1);
1016                   ip6_reass_drop_all (vm, rm, reass);
1017                   ip6_reass_free (rm, rt, reass);
1018                   goto next_packet;
1019                   break;
1020                 case IP6_REASS_RC_INTERNAL_ERROR:
1021                   vlib_node_increment_counter (vm, node->node_index,
1022                                                IP6_ERROR_REASS_INTERNAL_ERROR,
1023                                                1);
1024                   ip6_reass_drop_all (vm, rm, reass);
1025                   ip6_reass_free (rm, rt, reass);
1026                   goto next_packet;
1027                   break;
1028                 }
1029             }
1030           else
1031             {
1032               next0 = IP6_REASSEMBLY_NEXT_DROP;
1033               error0 = IP6_ERROR_REASS_LIMIT_REACHED;
1034             }
1035
1036           b0->error = node->errors[error0];
1037
1038           if (~0 != bi0)
1039             {
1040             skip_reass:
1041               to_next[0] = bi0;
1042               to_next += 1;
1043               n_left_to_next -= 1;
1044               if (is_feature && IP6_ERROR_NONE == error0)
1045                 {
1046                   b0 = vlib_get_buffer (vm, bi0);
1047                   vnet_feature_next (&next0, b0);
1048                 }
1049               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1050                                                n_left_to_next, bi0, next0);
1051             }
1052
1053           if (~0 != icmp_bi)
1054             {
1055               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
1056               to_next[0] = icmp_bi;
1057               to_next += 1;
1058               n_left_to_next -= 1;
1059               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1060                                                n_left_to_next, icmp_bi,
1061                                                next0);
1062             }
1063         next_packet:
1064           from += 1;
1065           n_left_from -= 1;
1066         }
1067
1068       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1069     }
1070
1071   clib_spinlock_unlock (&rt->lock);
1072   return frame->n_vectors;
1073 }
1074
1075 static char *ip6_reassembly_error_strings[] = {
1076 #define _(sym, string) string,
1077   foreach_ip6_error
1078 #undef _
1079 };
1080
1081 VLIB_NODE_FN (ip6_reass_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
1082                                vlib_frame_t * frame)
1083 {
1084   return ip6_reassembly_inline (vm, node, frame, false /* is_feature */ );
1085 }
1086
1087 /* *INDENT-OFF* */
1088 VLIB_REGISTER_NODE (ip6_reass_node) = {
1089     .name = "ip6-reassembly",
1090     .vector_size = sizeof (u32),
1091     .format_trace = format_ip6_reass_trace,
1092     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1093     .error_strings = ip6_reassembly_error_strings,
1094     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1095     .next_nodes =
1096         {
1097                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1098                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1099                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1100                 [IP6_REASSEMBLY_NEXT_HANDOFF] = "ip6-reassembly-handoff",
1101         },
1102 };
1103 /* *INDENT-ON* */
1104
1105 VLIB_NODE_FN (ip6_reass_node_feature) (vlib_main_t * vm,
1106                                        vlib_node_runtime_t * node,
1107                                        vlib_frame_t * frame)
1108 {
1109   return ip6_reassembly_inline (vm, node, frame, true /* is_feature */ );
1110 }
1111
1112 /* *INDENT-OFF* */
1113 VLIB_REGISTER_NODE (ip6_reass_node_feature) = {
1114     .name = "ip6-reassembly-feature",
1115     .vector_size = sizeof (u32),
1116     .format_trace = format_ip6_reass_trace,
1117     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1118     .error_strings = ip6_reassembly_error_strings,
1119     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1120     .next_nodes =
1121         {
1122                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1123                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1124                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1125                 [IP6_REASSEMBLY_NEXT_HANDOFF] = "ip6-reass-feature-hoff",
1126         },
1127 };
1128 /* *INDENT-ON* */
1129
1130 /* *INDENT-OFF* */
1131 VNET_FEATURE_INIT (ip6_reassembly_feature, static) = {
1132     .arc_name = "ip6-unicast",
1133     .node_name = "ip6-reassembly-feature",
1134     .runs_before = VNET_FEATURES ("ip6-lookup"),
1135     .runs_after = 0,
1136 };
1137 /* *INDENT-ON* */
1138
1139 #ifndef CLIB_MARCH_VARIANT
1140 static u32
1141 ip6_reass_get_nbuckets ()
1142 {
1143   ip6_reass_main_t *rm = &ip6_reass_main;
1144   u32 nbuckets;
1145   u8 i;
1146
1147   nbuckets = (u32) (rm->max_reass_n / IP6_REASS_HT_LOAD_FACTOR);
1148
1149   for (i = 0; i < 31; i++)
1150     if ((1 << i) >= nbuckets)
1151       break;
1152   nbuckets = 1 << i;
1153
1154   return nbuckets;
1155 }
1156 #endif /* CLIB_MARCH_VARIANT */
1157
1158 typedef enum
1159 {
1160   IP6_EVENT_CONFIG_CHANGED = 1,
1161 } ip6_reass_event_t;
1162
1163 #ifndef CLIB_MARCH_VARIANT
1164 typedef struct
1165 {
1166   int failure;
1167   clib_bihash_48_8_t *new_hash;
1168 } ip6_rehash_cb_ctx;
1169
1170 static void
1171 ip6_rehash_cb (clib_bihash_kv_48_8_t * kv, void *_ctx)
1172 {
1173   ip6_rehash_cb_ctx *ctx = _ctx;
1174   if (clib_bihash_add_del_48_8 (ctx->new_hash, kv, 1))
1175     {
1176       ctx->failure = 1;
1177     }
1178 }
1179
1180 static void
1181 ip6_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1182                       u32 max_reassembly_length, u32 expire_walk_interval_ms)
1183 {
1184   ip6_reass_main.timeout_ms = timeout_ms;
1185   ip6_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1186   ip6_reass_main.max_reass_n = max_reassemblies;
1187   ip6_reass_main.max_reass_len = max_reassembly_length;
1188   ip6_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1189 }
1190
1191 vnet_api_error_t
1192 ip6_reass_set (u32 timeout_ms, u32 max_reassemblies,
1193                u32 max_reassembly_length, u32 expire_walk_interval_ms)
1194 {
1195   u32 old_nbuckets = ip6_reass_get_nbuckets ();
1196   ip6_reass_set_params (timeout_ms, max_reassemblies, max_reassembly_length,
1197                         expire_walk_interval_ms);
1198   vlib_process_signal_event (ip6_reass_main.vlib_main,
1199                              ip6_reass_main.ip6_reass_expire_node_idx,
1200                              IP6_EVENT_CONFIG_CHANGED, 0);
1201   u32 new_nbuckets = ip6_reass_get_nbuckets ();
1202   if (ip6_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1203     {
1204       clib_bihash_48_8_t new_hash;
1205       clib_memset (&new_hash, 0, sizeof (new_hash));
1206       ip6_rehash_cb_ctx ctx;
1207       ctx.failure = 0;
1208       ctx.new_hash = &new_hash;
1209       clib_bihash_init_48_8 (&new_hash, "ip6-reass", new_nbuckets,
1210                              new_nbuckets * 1024);
1211       clib_bihash_foreach_key_value_pair_48_8 (&ip6_reass_main.hash,
1212                                                ip6_rehash_cb, &ctx);
1213       if (ctx.failure)
1214         {
1215           clib_bihash_free_48_8 (&new_hash);
1216           return -1;
1217         }
1218       else
1219         {
1220           clib_bihash_free_48_8 (&ip6_reass_main.hash);
1221           clib_memcpy_fast (&ip6_reass_main.hash, &new_hash,
1222                             sizeof (ip6_reass_main.hash));
1223         }
1224     }
1225   return 0;
1226 }
1227
1228 vnet_api_error_t
1229 ip6_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1230                u32 * expire_walk_interval_ms)
1231 {
1232   *timeout_ms = ip6_reass_main.timeout_ms;
1233   *max_reassemblies = ip6_reass_main.max_reass_n;
1234   *expire_walk_interval_ms = ip6_reass_main.expire_walk_interval_ms;
1235   return 0;
1236 }
1237
1238 static clib_error_t *
1239 ip6_reass_init_function (vlib_main_t * vm)
1240 {
1241   ip6_reass_main_t *rm = &ip6_reass_main;
1242   clib_error_t *error = 0;
1243   u32 nbuckets;
1244   vlib_node_t *node;
1245
1246   rm->vlib_main = vm;
1247   rm->vnet_main = vnet_get_main ();
1248
1249   vec_validate (rm->per_thread_data, vlib_num_workers ());
1250   ip6_reass_per_thread_t *rt;
1251   vec_foreach (rt, rm->per_thread_data)
1252   {
1253     clib_spinlock_init (&rt->lock);
1254     pool_alloc (rt->pool, rm->max_reass_n);
1255   }
1256
1257   node = vlib_get_node_by_name (vm, (u8 *) "ip6-reassembly-expire-walk");
1258   ASSERT (node);
1259   rm->ip6_reass_expire_node_idx = node->index;
1260
1261   ip6_reass_set_params (IP6_REASS_TIMEOUT_DEFAULT_MS,
1262                         IP6_REASS_MAX_REASSEMBLIES_DEFAULT,
1263                         IP6_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT,
1264                         IP6_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1265
1266   nbuckets = ip6_reass_get_nbuckets ();
1267   clib_bihash_init_48_8 (&rm->hash, "ip6-reass", nbuckets, nbuckets * 1024);
1268
1269   node = vlib_get_node_by_name (vm, (u8 *) "ip6-drop");
1270   ASSERT (node);
1271   rm->ip6_drop_idx = node->index;
1272   node = vlib_get_node_by_name (vm, (u8 *) "ip6-icmp-error");
1273   ASSERT (node);
1274   rm->ip6_icmp_error_idx = node->index;
1275
1276   if ((error = vlib_call_init_function (vm, ip_main_init)))
1277     return error;
1278   ip6_register_protocol (IP_PROTOCOL_IPV6_FRAGMENTATION,
1279                          ip6_reass_node.index);
1280
1281   rm->fq_index = vlib_frame_queue_main_init (ip6_reass_node.index, 0);
1282   rm->fq_feature_index =
1283     vlib_frame_queue_main_init (ip6_reass_node_feature.index, 0);
1284
1285   return error;
1286 }
1287
1288 VLIB_INIT_FUNCTION (ip6_reass_init_function);
1289 #endif /* CLIB_MARCH_VARIANT */
1290
1291 static uword
1292 ip6_reass_walk_expired (vlib_main_t * vm,
1293                         vlib_node_runtime_t * node, vlib_frame_t * f)
1294 {
1295   ip6_reass_main_t *rm = &ip6_reass_main;
1296   uword event_type, *event_data = 0;
1297
1298   while (true)
1299     {
1300       vlib_process_wait_for_event_or_clock (vm,
1301                                             (f64) rm->expire_walk_interval_ms
1302                                             / (f64) MSEC_PER_SEC);
1303       event_type = vlib_process_get_events (vm, &event_data);
1304
1305       switch (event_type)
1306         {
1307         case ~0:                /* no events => timeout */
1308           /* nothing to do here */
1309           break;
1310         case IP6_EVENT_CONFIG_CHANGED:
1311           break;
1312         default:
1313           clib_warning ("BUG: event type 0x%wx", event_type);
1314           break;
1315         }
1316       f64 now = vlib_time_now (vm);
1317
1318       ip6_reass_t *reass;
1319       int *pool_indexes_to_free = NULL;
1320
1321       uword thread_index = 0;
1322       int index;
1323       const uword nthreads = vlib_num_workers () + 1;
1324       u32 *vec_icmp_bi = NULL;
1325       for (thread_index = 0; thread_index < nthreads; ++thread_index)
1326         {
1327           ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1328           clib_spinlock_lock (&rt->lock);
1329
1330           vec_reset_length (pool_indexes_to_free);
1331           /* *INDENT-OFF* */
1332           pool_foreach_index (index, rt->pool, ({
1333                                 reass = pool_elt_at_index (rt->pool, index);
1334                                 if (now > reass->last_heard + rm->timeout)
1335                                   {
1336                                     vec_add1 (pool_indexes_to_free, index);
1337                                   }
1338                               }));
1339           /* *INDENT-ON* */
1340           int *i;
1341           /* *INDENT-OFF* */
1342           vec_foreach (i, pool_indexes_to_free)
1343           {
1344             ip6_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1345             u32 icmp_bi = ~0;
1346             vlib_buffer_t *b = vlib_get_buffer (vm, reass->first_bi);
1347             if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1348               {
1349                 if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1350                                         b->trace_index))
1351                   {
1352                     /* the trace is gone, don't trace this buffer anymore */
1353                     b->flags &= ~VLIB_BUFFER_IS_TRACED;
1354                   }
1355               }
1356             ip6_reass_on_timeout (vm, node, rm, reass, &icmp_bi);
1357             if (~0 != icmp_bi)
1358               {
1359                 vec_add1 (vec_icmp_bi, icmp_bi);
1360               }
1361             ip6_reass_free (rm, rt, reass);
1362           }
1363           /* *INDENT-ON* */
1364
1365           clib_spinlock_unlock (&rt->lock);
1366         }
1367
1368       while (vec_len (vec_icmp_bi) > 0)
1369         {
1370           vlib_frame_t *f =
1371             vlib_get_frame_to_node (vm, rm->ip6_icmp_error_idx);
1372           u32 *to_next = vlib_frame_vector_args (f);
1373           u32 n_left_to_next = VLIB_FRAME_SIZE - f->n_vectors;
1374           int trace_frame = 0;
1375           while (vec_len (vec_icmp_bi) > 0 && n_left_to_next > 0)
1376             {
1377               u32 bi = vec_pop (vec_icmp_bi);
1378               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1379               if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1380                 {
1381                   if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1382                                           b->trace_index))
1383                     {
1384                       /* the trace is gone, don't trace this buffer anymore */
1385                       b->flags &= ~VLIB_BUFFER_IS_TRACED;
1386                     }
1387                   else
1388                     {
1389                       trace_frame = 1;
1390                     }
1391                 }
1392               b->error = node->errors[IP6_ERROR_REASS_TIMEOUT];
1393               to_next[0] = bi;
1394               ++f->n_vectors;
1395               to_next += 1;
1396               n_left_to_next -= 1;
1397             }
1398           f->frame_flags |= (trace_frame * VLIB_FRAME_TRACE);
1399           vlib_put_frame_to_node (vm, rm->ip6_icmp_error_idx, f);
1400         }
1401
1402       vec_free (pool_indexes_to_free);
1403       vec_free (vec_icmp_bi);
1404       if (event_data)
1405         {
1406           _vec_len (event_data) = 0;
1407         }
1408     }
1409
1410   return 0;
1411 }
1412
1413 /* *INDENT-OFF* */
1414 VLIB_REGISTER_NODE (ip6_reass_expire_node, static) = {
1415     .function = ip6_reass_walk_expired,
1416     .format_trace = format_ip6_reass_trace,
1417     .type = VLIB_NODE_TYPE_PROCESS,
1418     .name = "ip6-reassembly-expire-walk",
1419
1420     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1421     .error_strings = ip6_reassembly_error_strings,
1422
1423 };
1424 /* *INDENT-ON* */
1425
1426 static u8 *
1427 format_ip6_reass_key (u8 * s, va_list * args)
1428 {
1429   ip6_reass_key_t *key = va_arg (*args, ip6_reass_key_t *);
1430   s = format (s, "xx_id: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1431               key->xx_id, format_ip6_address, &key->src, format_ip6_address,
1432               &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1433   return s;
1434 }
1435
1436 static u8 *
1437 format_ip6_reass (u8 * s, va_list * args)
1438 {
1439   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1440   ip6_reass_t *reass = va_arg (*args, ip6_reass_t *);
1441
1442   s = format (s, "ID: %lu, key: %U\n  first_bi: %u, data_len: %u, "
1443               "last_packet_octet: %u, trace_op_counter: %u\n",
1444               reass->id, format_ip6_reass_key, &reass->key, reass->first_bi,
1445               reass->data_len, reass->last_packet_octet,
1446               reass->trace_op_counter);
1447   u32 bi = reass->first_bi;
1448   u32 counter = 0;
1449   while (~0 != bi)
1450     {
1451       vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1452       vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1453       s = format (s, "  #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1454                   "fragment[%u, %u]\n",
1455                   counter, vnb->ip.reass.range_first,
1456                   vnb->ip.reass.range_last, bi,
1457                   ip6_reass_buffer_get_data_offset (b),
1458                   ip6_reass_buffer_get_data_len (b),
1459                   vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1460       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1461         {
1462           bi = b->next_buffer;
1463         }
1464       else
1465         {
1466           bi = ~0;
1467         }
1468     }
1469   return s;
1470 }
1471
1472 static clib_error_t *
1473 show_ip6_reass (vlib_main_t * vm, unformat_input_t * input,
1474                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1475 {
1476   ip6_reass_main_t *rm = &ip6_reass_main;
1477
1478   vlib_cli_output (vm, "---------------------");
1479   vlib_cli_output (vm, "IP6 reassembly status");
1480   vlib_cli_output (vm, "---------------------");
1481   bool details = false;
1482   if (unformat (input, "details"))
1483     {
1484       details = true;
1485     }
1486
1487   u32 sum_reass_n = 0;
1488   u64 sum_buffers_n = 0;
1489   ip6_reass_t *reass;
1490   uword thread_index;
1491   const uword nthreads = vlib_num_workers () + 1;
1492   for (thread_index = 0; thread_index < nthreads; ++thread_index)
1493     {
1494       ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1495       clib_spinlock_lock (&rt->lock);
1496       if (details)
1497         {
1498           /* *INDENT-OFF* */
1499           pool_foreach (reass, rt->pool, {
1500             vlib_cli_output (vm, "%U", format_ip6_reass, vm, reass);
1501           });
1502           /* *INDENT-ON* */
1503         }
1504       sum_reass_n += rt->reass_n;
1505       clib_spinlock_unlock (&rt->lock);
1506     }
1507   vlib_cli_output (vm, "---------------------");
1508   vlib_cli_output (vm, "Current IP6 reassemblies count: %lu\n",
1509                    (long unsigned) sum_reass_n);
1510   vlib_cli_output (vm, "Maximum configured concurrent IP6 reassemblies per "
1511                    "worker-thread: %lu\n", (long unsigned) rm->max_reass_n);
1512   vlib_cli_output (vm, "Buffers in use: %lu\n",
1513                    (long unsigned) sum_buffers_n);
1514   return 0;
1515 }
1516
1517 /* *INDENT-OFF* */
1518 VLIB_CLI_COMMAND (show_ip6_reassembly_cmd, static) = {
1519     .path = "show ip6-reassembly",
1520     .short_help = "show ip6-reassembly [details]",
1521     .function = show_ip6_reass,
1522 };
1523 /* *INDENT-ON* */
1524
1525 #ifndef CLIB_MARCH_VARIANT
1526 vnet_api_error_t
1527 ip6_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1528 {
1529   return vnet_feature_enable_disable ("ip6-unicast", "ip6-reassembly-feature",
1530                                       sw_if_index, enable_disable, 0, 0);
1531 }
1532 #endif /* CLIB_MARCH_VARIANT */
1533
1534 #define foreach_ip6_reassembly_handoff_error                       \
1535 _(CONGESTION_DROP, "congestion drop")
1536
1537
1538 typedef enum
1539 {
1540 #define _(sym,str) IP6_REASSEMBLY_HANDOFF_ERROR_##sym,
1541   foreach_ip6_reassembly_handoff_error
1542 #undef _
1543     IP6_REASSEMBLY_HANDOFF_N_ERROR,
1544 } ip6_reassembly_handoff_error_t;
1545
1546 static char *ip6_reassembly_handoff_error_strings[] = {
1547 #define _(sym,string) string,
1548   foreach_ip6_reassembly_handoff_error
1549 #undef _
1550 };
1551
1552 typedef struct
1553 {
1554   u32 next_worker_index;
1555 } ip6_reassembly_handoff_trace_t;
1556
1557 static u8 *
1558 format_ip6_reassembly_handoff_trace (u8 * s, va_list * args)
1559 {
1560   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1561   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1562   ip6_reassembly_handoff_trace_t *t =
1563     va_arg (*args, ip6_reassembly_handoff_trace_t *);
1564
1565   s =
1566     format (s, "ip6-reassembly-handoff: next-worker %d",
1567             t->next_worker_index);
1568
1569   return s;
1570 }
1571
1572 always_inline uword
1573 ip6_reassembly_handoff_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1574                                vlib_frame_t * frame, bool is_feature)
1575 {
1576   ip6_reass_main_t *rm = &ip6_reass_main;
1577
1578   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1579   u32 n_enq, n_left_from, *from;
1580   u16 thread_indices[VLIB_FRAME_SIZE], *ti;
1581   u32 fq_index;
1582
1583   from = vlib_frame_vector_args (frame);
1584   n_left_from = frame->n_vectors;
1585   vlib_get_buffers (vm, from, bufs, n_left_from);
1586
1587   b = bufs;
1588   ti = thread_indices;
1589
1590   fq_index = (is_feature) ? rm->fq_feature_index : rm->fq_index;
1591
1592   while (n_left_from > 0)
1593     {
1594       ti[0] =
1595         (is_feature) ? vnet_buffer (b[0])->ip.
1596         reass.owner_feature_thread_index : vnet_buffer (b[0])->ip.
1597         reass.owner_thread_index;
1598
1599       if (PREDICT_FALSE
1600           ((node->flags & VLIB_NODE_FLAG_TRACE)
1601            && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
1602         {
1603           ip6_reassembly_handoff_trace_t *t =
1604             vlib_add_trace (vm, node, b[0], sizeof (*t));
1605           t->next_worker_index = ti[0];
1606         }
1607
1608       n_left_from -= 1;
1609       ti += 1;
1610       b += 1;
1611     }
1612   n_enq =
1613     vlib_buffer_enqueue_to_thread (vm, fq_index, from, thread_indices,
1614                                    frame->n_vectors, 1);
1615
1616   if (n_enq < frame->n_vectors)
1617     vlib_node_increment_counter (vm, node->node_index,
1618                                  IP6_REASSEMBLY_HANDOFF_ERROR_CONGESTION_DROP,
1619                                  frame->n_vectors - n_enq);
1620   return frame->n_vectors;
1621 }
1622
1623 VLIB_NODE_FN (ip6_reassembly_handoff_node) (vlib_main_t * vm,
1624                                             vlib_node_runtime_t * node,
1625                                             vlib_frame_t * frame)
1626 {
1627   return ip6_reassembly_handoff_inline (vm, node, frame,
1628                                         false /* is_feature */ );
1629 }
1630
1631 /* *INDENT-OFF* */
1632 VLIB_REGISTER_NODE (ip6_reassembly_handoff_node) = {
1633   .name = "ip6-reassembly-handoff",
1634   .vector_size = sizeof (u32),
1635   .n_errors = ARRAY_LEN(ip6_reassembly_handoff_error_strings),
1636   .error_strings = ip6_reassembly_handoff_error_strings,
1637   .format_trace = format_ip6_reassembly_handoff_trace,
1638
1639   .n_next_nodes = 1,
1640
1641   .next_nodes = {
1642     [0] = "error-drop",
1643   },
1644 };
1645
1646
1647 VLIB_NODE_FN (ip6_reassembly_feature_handoff_node) (vlib_main_t * vm,
1648                                vlib_node_runtime_t * node, vlib_frame_t * frame)
1649 {
1650   return ip6_reassembly_handoff_inline (vm, node, frame, true /* is_feature */ );
1651 }
1652
1653
1654 /* *INDENT-OFF* */
1655 VLIB_REGISTER_NODE (ip6_reassembly_feature_handoff_node) = {
1656   .name = "ip6-reass-feature-hoff",
1657   .vector_size = sizeof (u32),
1658   .n_errors = ARRAY_LEN(ip6_reassembly_handoff_error_strings),
1659   .error_strings = ip6_reassembly_handoff_error_strings,
1660   .format_trace = format_ip6_reassembly_handoff_trace,
1661
1662   .n_next_nodes = 1,
1663
1664   .next_nodes = {
1665     [0] = "error-drop",
1666   },
1667 };
1668 /* *INDENT-ON* */
1669
1670 /*
1671  * fd.io coding-style-patch-verification: ON
1672  *
1673  * Local Variables:
1674  * eval: (c-set-style "gnu")
1675  * End:
1676  */