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