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   first_b->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
 637   if (PREDICT_FALSE (first_b->flags & VLIB_BUFFER_IS_TRACED))
 638     {
 639       ip6_reass_add_trace (vm, node, rm, reass, reass->first_bi, FINALIZE, 0);
 640 #if 0
 641       // following code does a hexdump of packet fragments to stdout ...
 642       do
 643         {
 644           u32 bi = reass->first_bi;
 645           u8 *s = NULL;
 646           while (~0 != bi)
 647             {
 648               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 649               s = format (s, "%u: %U\n", bi, format_hexdump,
 650                           vlib_buffer_get_current (b), b->current_length);
 651               if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 652                 {
 653                   bi = b->next_buffer;
 654                 }
 655               else
 656                 {
 657                   break;
 658                 }
 659             }
 660           printf ("%.*s\n", vec_len (s), s);
 661           fflush (stdout);
 662           vec_free (s);
 663         }
 664       while (0);
 665 #endif
 666     }
 667   if (is_feature)
 668     {
 669       *next0 = IP6_REASSEMBLY_NEXT_INPUT;
 670     }
 671   else
 672     {
 673       *next0 = reass->next_index;
 674     }
 675   vnet_buffer (first_b)->ip.reass.estimated_mtu = reass->min_fragment_length;
 676   ip6_reass_free (rm, rt, reass);
 677   reass = NULL;
 678 free_buffers_and_return:
 679   vlib_buffer_free (vm, vec_drop_compress, vec_len (vec_drop_compress));
 680   vec_free (vec_drop_compress);
 681   return rv;
 682 }
 683
 684 always_inline void
 685 ip6_reass_insert_range_in_chain (vlib_main_t * vm, ip6_reass_main_t * rm,
 686                                  ip6_reass_per_thread_t * rt,
 687                                  ip6_reass_t * reass, u32 prev_range_bi,
 688                                  u32 new_next_bi)
 689 {
 690
 691   vlib_buffer_t *new_next_b = vlib_get_buffer (vm, new_next_bi);
 692   vnet_buffer_opaque_t *new_next_vnb = vnet_buffer (new_next_b);
 693   if (~0 != prev_range_bi)
 694     {
 695       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
 696       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
 697       new_next_vnb->ip.reass.next_range_bi = prev_vnb->ip.reass.next_range_bi;
 698       prev_vnb->ip.reass.next_range_bi = new_next_bi;
 699     }
 700   else
 701     {
 702       if (~0 != reass->first_bi)
 703         {
 704           new_next_vnb->ip.reass.next_range_bi = reass->first_bi;
 705         }
 706       reass->first_bi = new_next_bi;
 707     }
 708   reass->data_len += ip6_reass_buffer_get_data_len (new_next_b);
 709 }
 710
 711 always_inline ip6_reass_rc_t
 712 ip6_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
 713                   ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 714                   ip6_reass_t * reass, u32 * bi0, u32 * next0, u32 * error0,
 715                   ip6_frag_hdr_t * frag_hdr, bool is_feature)
 716 {
 717   int consumed = 0;
 718   vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
 719   vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
 720   reass->next_index = fvnb->ip.reass.next_index;        // store next_index before it's overwritten
 721   fvnb->ip.reass.ip6_frag_hdr_offset =
 722     (u8 *) frag_hdr - (u8 *) vlib_buffer_get_current (fb);
 723   ip6_header_t *fip = vlib_buffer_get_current (fb);
 724   if (fb->current_length < sizeof (*fip) ||
 725       fvnb->ip.reass.ip6_frag_hdr_offset == 0 ||
 726       fvnb->ip.reass.ip6_frag_hdr_offset >= fb->current_length)
 727     {
 728       return IP6_REASS_RC_INTERNAL_ERROR;
 729     }
 730
 731   u32 fragment_first = fvnb->ip.reass.fragment_first =
 732     ip6_frag_hdr_offset_bytes (frag_hdr);
 733   u32 fragment_length =
 734     vlib_buffer_length_in_chain (vm, fb) -
 735     (fvnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 736   u32 fragment_last = fvnb->ip.reass.fragment_last =
 737     fragment_first + fragment_length - 1;
 738   int more_fragments = ip6_frag_hdr_more (frag_hdr);
 739   u32 candidate_range_bi = reass->first_bi;
 740   u32 prev_range_bi = ~0;
 741   fvnb->ip.reass.range_first = fragment_first;
 742   fvnb->ip.reass.range_last = fragment_last;
 743   fvnb->ip.reass.next_range_bi = ~0;
 744   if (!more_fragments)
 745     {
 746       reass->last_packet_octet = fragment_last;
 747     }
 748   if (~0 == reass->first_bi)
 749     {
 750       // starting a new reassembly
 751       ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
 752                                        *bi0);
 753       reass->min_fragment_length = clib_net_to_host_u16 (fip->payload_length);
 754       consumed = 1;
 755       reass->fragments_n = 1;
 756       goto check_if_done_maybe;
 757     }
 758   reass->min_fragment_length =
 759     clib_min (clib_net_to_host_u16 (fip->payload_length),
 760               fvnb->ip.reass.estimated_mtu);
 761   while (~0 != candidate_range_bi)
 762     {
 763       vlib_buffer_t *candidate_b = vlib_get_buffer (vm, candidate_range_bi);
 764       vnet_buffer_opaque_t *candidate_vnb = vnet_buffer (candidate_b);
 765       if (fragment_first > candidate_vnb->ip.reass.range_last)
 766         {
 767           // this fragments starts after candidate range
 768           prev_range_bi = candidate_range_bi;
 769           candidate_range_bi = candidate_vnb->ip.reass.next_range_bi;
 770           if (candidate_vnb->ip.reass.range_last < fragment_last &&
 771               ~0 == candidate_range_bi)
 772             {
 773               // special case - this fragment falls beyond all known ranges
 774               ip6_reass_insert_range_in_chain (vm, rm, rt, reass,
 775                                                prev_range_bi, *bi0);
 776               consumed = 1;
 777               break;
 778             }
 779           continue;
 780         }
 781       if (fragment_last < candidate_vnb->ip.reass.range_first)
 782         {
 783           // this fragment ends before candidate range without any overlap
 784           ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
 785                                            *bi0);
 786           consumed = 1;
 787         }
 788       else if (fragment_first == candidate_vnb->ip.reass.range_first &&
 789                fragment_last == candidate_vnb->ip.reass.range_last)
 790         {
 791           // duplicate fragment - ignore
 792         }
 793       else
 794         {
 795           // overlapping fragment - not allowed by RFC 8200
 796           ip6_reass_drop_all (vm, rm, reass);
 797           ip6_reass_free (rm, rt, reass);
 798           if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 799             {
 800               ip6_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_OVERLAP,
 801                                    0);
 802             }
 803           *next0 = IP6_REASSEMBLY_NEXT_DROP;
 804           *error0 = IP6_ERROR_REASS_OVERLAPPING_FRAGMENT;
 805           return IP6_REASS_RC_OK;
 806         }
 807       break;
 808     }
 809   ++reass->fragments_n;
 810 check_if_done_maybe:
 811   if (consumed)
 812     {
 813       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 814         {
 815           ip6_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
 816         }
 817     }
 818   if (~0 != reass->last_packet_octet &&
 819       reass->data_len == reass->last_packet_octet + 1)
 820     {
 821       return ip6_reass_finalize (vm, node, rm, rt, reass, bi0, next0, error0,
 822                                  is_feature);
 823     }
 824   else
 825     {
 826       if (consumed)
 827         {
 828           *bi0 = ~0;
 829           if (reass->fragments_n > rm->max_reass_len)
 830             {
 831               return IP6_REASS_RC_TOO_MANY_FRAGMENTS;
 832             }
 833         }
 834       else
 835         {
 836           *next0 = IP6_REASSEMBLY_NEXT_DROP;
 837           *error0 = IP6_ERROR_REASS_DUPLICATE_FRAGMENT;
 838         }
 839     }
 840   return IP6_REASS_RC_OK;
 841 }
 842
 843 always_inline bool
 844 ip6_reass_verify_upper_layer_present (vlib_node_runtime_t * node,
 845                                       vlib_buffer_t * b,
 846                                       ip6_frag_hdr_t * frag_hdr)
 847 {
 848   ip6_ext_header_t *tmp = (ip6_ext_header_t *) frag_hdr;
 849   while (ip6_ext_hdr (tmp->next_hdr))
 850     {
 851       tmp = ip6_ext_next_header (tmp);
 852     }
 853   if (IP_PROTOCOL_IP6_NONXT == tmp->next_hdr)
 854     {
 855       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 856                                    ICMP6_parameter_problem_first_fragment_has_incomplete_header_chain,
 857                                    0);
 858       b->error = node->errors[IP6_ERROR_REASS_MISSING_UPPER];
 859
 860       return false;
 861     }
 862   return true;
 863 }
 864
 865 always_inline bool
 866 ip6_reass_verify_fragment_multiple_8 (vlib_main_t * vm,
 867                                       vlib_node_runtime_t * node,
 868                                       vlib_buffer_t * b,
 869                                       ip6_frag_hdr_t * frag_hdr)
 870 {
 871   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 872   ip6_header_t *ip = vlib_buffer_get_current (b);
 873   int more_fragments = ip6_frag_hdr_more (frag_hdr);
 874   u32 fragment_length =
 875     vlib_buffer_length_in_chain (vm, b) -
 876     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 877   if (more_fragments && 0 != fragment_length % 8)
 878     {
 879       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 880                                    ICMP6_parameter_problem_erroneous_header_field,
 881                                    (u8 *) & ip->payload_length - (u8 *) ip);
 882       return false;
 883     }
 884   return true;
 885 }
 886
 887 always_inline bool
 888 ip6_reass_verify_packet_size_lt_64k (vlib_main_t * vm,
 889                                      vlib_node_runtime_t * node,
 890                                      vlib_buffer_t * b,
 891                                      ip6_frag_hdr_t * frag_hdr)
 892 {
 893   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 894   u32 fragment_first = ip6_frag_hdr_offset_bytes (frag_hdr);
 895   u32 fragment_length =
 896     vlib_buffer_length_in_chain (vm, b) -
 897     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 898   if (fragment_first + fragment_length > 65535)
 899     {
 900       ip6_header_t *ip0 = vlib_buffer_get_current (b);
 901       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 902                                    ICMP6_parameter_problem_erroneous_header_field,
 903                                    (u8 *) & frag_hdr->fragment_offset_and_more
 904                                    - (u8 *) ip0);
 905       return false;
 906     }
 907   return true;
 908 }
 909
 910 always_inline uword
 911 ip6_reassembly_inline (vlib_main_t * vm,
 912                        vlib_node_runtime_t * node,
 913                        vlib_frame_t * frame, bool is_feature)
 914 {
 915   u32 *from = vlib_frame_vector_args (frame);
 916   u32 n_left_from, n_left_to_next, *to_next, next_index;
 917   ip6_reass_main_t *rm = &ip6_reass_main;
 918   ip6_reass_per_thread_t *rt = &rm->per_thread_data[vm->thread_index];
 919   clib_spinlock_lock (&rt->lock);
 920
 921   n_left_from = frame->n_vectors;
 922   next_index = node->cached_next_index;
 923   while (n_left_from > 0)
 924     {
 925       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 926
 927       while (n_left_from > 0 && n_left_to_next > 0)
 928         {
 929           u32 bi0;
 930           vlib_buffer_t *b0;
 931           u32 next0 = IP6_REASSEMBLY_NEXT_DROP;
 932           u32 error0 = IP6_ERROR_NONE;
 933           u32 icmp_bi = ~0;
 934
 935           bi0 = from[0];
 936           b0 = vlib_get_buffer (vm, bi0);
 937
 938           ip6_header_t *ip0 = vlib_buffer_get_current (b0);
 939           ip6_frag_hdr_t *frag_hdr = NULL;
 940           ip6_ext_header_t *prev_hdr;
 941           if (ip6_ext_hdr (ip0->protocol))
 942             {
 943               ip6_ext_header_find_t (ip0, prev_hdr, frag_hdr,
 944                                      IP_PROTOCOL_IPV6_FRAGMENTATION);
 945             }
 946           if (!frag_hdr)
 947             {
 948               // this is a regular packet - no fragmentation
 949               next0 = IP6_REASSEMBLY_NEXT_INPUT;
 950               goto skip_reass;
 951             }
 952           if (0 == ip6_frag_hdr_offset (frag_hdr))
 953             {
 954               // first fragment - verify upper-layer is present
 955               if (!ip6_reass_verify_upper_layer_present (node, b0, frag_hdr))
 956                 {
 957                   next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
 958                   goto skip_reass;
 959                 }
 960             }
 961           if (!ip6_reass_verify_fragment_multiple_8 (vm, node, b0, frag_hdr)
 962               || !ip6_reass_verify_packet_size_lt_64k (vm, node, b0,
 963                                                        frag_hdr))
 964             {
 965               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
 966               goto skip_reass;
 967             }
 968           vnet_buffer (b0)->ip.reass.ip6_frag_hdr_offset =
 969             (u8 *) frag_hdr - (u8 *) ip0;
 970
 971           ip6_reass_kv_t kv;
 972           u8 do_handoff = 0;
 973
 974           kv.k.as_u64[0] = ip0->src_address.as_u64[0];
 975           kv.k.as_u64[1] = ip0->src_address.as_u64[1];
 976           kv.k.as_u64[2] = ip0->dst_address.as_u64[0];
 977           kv.k.as_u64[3] = ip0->dst_address.as_u64[1];
 978           kv.k.as_u64[4] =
 979             ((u64) vec_elt (ip6_main.fib_index_by_sw_if_index,
 980                             vnet_buffer (b0)->sw_if_index[VLIB_RX])) << 32 |
 981             (u64) frag_hdr->identification;
 982           kv.k.as_u64[5] = ip0->protocol;
 983
 984           ip6_reass_t *reass =
 985             ip6_reass_find_or_create (vm, node, rm, rt, &kv, &icmp_bi,
 986                                       &do_handoff);
 987
 988           if (PREDICT_FALSE (do_handoff))
 989             {
 990               next0 = IP6_REASSEMBLY_NEXT_HANDOFF;
 991               if (is_feature)
 992                 vnet_buffer (b0)->ip.reass.owner_feature_thread_index =
 993                   kv.v.thread_index;
 994               else
 995                 vnet_buffer (b0)->ip.reass.owner_thread_index =
 996                   kv.v.thread_index;
 997             }
 998           else if (reass)
 999             {
1000               switch (ip6_reass_update (vm, node, rm, rt, reass, &bi0, &next0,
1001                                         &error0, frag_hdr, is_feature))
1002                 {
1003                 case IP6_REASS_RC_OK:
1004                   /* nothing to do here */
1005                   break;
1006                 case IP6_REASS_RC_TOO_MANY_FRAGMENTS:
1007                   vlib_node_increment_counter (vm, node->node_index,
1008                                                IP6_ERROR_REASS_FRAGMENT_CHAIN_TOO_LONG,
1009                                                1);
1010                   ip6_reass_drop_all (vm, rm, reass);
1011                   ip6_reass_free (rm, rt, reass);
1012                   goto next_packet;
1013                   break;
1014                 case IP6_REASS_RC_NO_BUF:
1015                   vlib_node_increment_counter (vm, node->node_index,
1016                                                IP6_ERROR_REASS_NO_BUF, 1);
1017                   ip6_reass_drop_all (vm, rm, reass);
1018                   ip6_reass_free (rm, rt, reass);
1019                   goto next_packet;
1020                   break;
1021                 case IP6_REASS_RC_INTERNAL_ERROR:
1022                   vlib_node_increment_counter (vm, node->node_index,
1023                                                IP6_ERROR_REASS_INTERNAL_ERROR,
1024                                                1);
1025                   ip6_reass_drop_all (vm, rm, reass);
1026                   ip6_reass_free (rm, rt, reass);
1027                   goto next_packet;
1028                   break;
1029                 }
1030             }
1031           else
1032             {
1033               next0 = IP6_REASSEMBLY_NEXT_DROP;
1034               error0 = IP6_ERROR_REASS_LIMIT_REACHED;
1035             }
1036
1037           b0->error = node->errors[error0];
1038
1039           if (~0 != bi0)
1040             {
1041             skip_reass:
1042               to_next[0] = bi0;
1043               to_next += 1;
1044               n_left_to_next -= 1;
1045               if (is_feature && IP6_ERROR_NONE == error0)
1046                 {
1047                   b0 = vlib_get_buffer (vm, bi0);
1048                   vnet_feature_next (&next0, b0);
1049                 }
1050               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1051                                                n_left_to_next, bi0, next0);
1052             }
1053
1054           if (~0 != icmp_bi)
1055             {
1056               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
1057               to_next[0] = icmp_bi;
1058               to_next += 1;
1059               n_left_to_next -= 1;
1060               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1061                                                n_left_to_next, icmp_bi,
1062                                                next0);
1063             }
1064         next_packet:
1065           from += 1;
1066           n_left_from -= 1;
1067         }
1068
1069       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1070     }
1071
1072   clib_spinlock_unlock (&rt->lock);
1073   return frame->n_vectors;
1074 }
1075
1076 static char *ip6_reassembly_error_strings[] = {
1077 #define _(sym, string) string,
1078   foreach_ip6_error
1079 #undef _
1080 };
1081
1082 VLIB_NODE_FN (ip6_reass_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
1083                                vlib_frame_t * frame)
1084 {
1085   return ip6_reassembly_inline (vm, node, frame, false /* is_feature */ );
1086 }
1087
1088 /* *INDENT-OFF* */
1089 VLIB_REGISTER_NODE (ip6_reass_node) = {
1090     .name = "ip6-reassembly",
1091     .vector_size = sizeof (u32),
1092     .format_trace = format_ip6_reass_trace,
1093     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1094     .error_strings = ip6_reassembly_error_strings,
1095     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1096     .next_nodes =
1097         {
1098                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1099                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1100                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1101                 [IP6_REASSEMBLY_NEXT_HANDOFF] = "ip6-reassembly-handoff",
1102         },
1103 };
1104 /* *INDENT-ON* */
1105
1106 VLIB_NODE_FN (ip6_reass_node_feature) (vlib_main_t * vm,
1107                                        vlib_node_runtime_t * node,
1108                                        vlib_frame_t * frame)
1109 {
1110   return ip6_reassembly_inline (vm, node, frame, true /* is_feature */ );
1111 }
1112
1113 /* *INDENT-OFF* */
1114 VLIB_REGISTER_NODE (ip6_reass_node_feature) = {
1115     .name = "ip6-reassembly-feature",
1116     .vector_size = sizeof (u32),
1117     .format_trace = format_ip6_reass_trace,
1118     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1119     .error_strings = ip6_reassembly_error_strings,
1120     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1121     .next_nodes =
1122         {
1123                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1124                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1125                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1126                 [IP6_REASSEMBLY_NEXT_HANDOFF] = "ip6-reass-feature-hoff",
1127         },
1128 };
1129 /* *INDENT-ON* */
1130
1131 /* *INDENT-OFF* */
1132 VNET_FEATURE_INIT (ip6_reassembly_feature, static) = {
1133     .arc_name = "ip6-unicast",
1134     .node_name = "ip6-reassembly-feature",
1135     .runs_before = VNET_FEATURES ("ip6-lookup"),
1136     .runs_after = 0,
1137 };
1138 /* *INDENT-ON* */
1139
1140 #ifndef CLIB_MARCH_VARIANT
1141 static u32
1142 ip6_reass_get_nbuckets ()
1143 {
1144   ip6_reass_main_t *rm = &ip6_reass_main;
1145   u32 nbuckets;
1146   u8 i;
1147
1148   nbuckets = (u32) (rm->max_reass_n / IP6_REASS_HT_LOAD_FACTOR);
1149
1150   for (i = 0; i < 31; i++)
1151     if ((1 << i) >= nbuckets)
1152       break;
1153   nbuckets = 1 << i;
1154
1155   return nbuckets;
1156 }
1157 #endif /* CLIB_MARCH_VARIANT */
1158
1159 typedef enum
1160 {
1161   IP6_EVENT_CONFIG_CHANGED = 1,
1162 } ip6_reass_event_t;
1163
1164 #ifndef CLIB_MARCH_VARIANT
1165 typedef struct
1166 {
1167   int failure;
1168   clib_bihash_48_8_t *new_hash;
1169 } ip6_rehash_cb_ctx;
1170
1171 static void
1172 ip6_rehash_cb (clib_bihash_kv_48_8_t * kv, void *_ctx)
1173 {
1174   ip6_rehash_cb_ctx *ctx = _ctx;
1175   if (clib_bihash_add_del_48_8 (ctx->new_hash, kv, 1))
1176     {
1177       ctx->failure = 1;
1178     }
1179 }
1180
1181 static void
1182 ip6_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1183                       u32 max_reassembly_length, u32 expire_walk_interval_ms)
1184 {
1185   ip6_reass_main.timeout_ms = timeout_ms;
1186   ip6_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1187   ip6_reass_main.max_reass_n = max_reassemblies;
1188   ip6_reass_main.max_reass_len = max_reassembly_length;
1189   ip6_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1190 }
1191
1192 vnet_api_error_t
1193 ip6_reass_set (u32 timeout_ms, u32 max_reassemblies,
1194                u32 max_reassembly_length, u32 expire_walk_interval_ms)
1195 {
1196   u32 old_nbuckets = ip6_reass_get_nbuckets ();
1197   ip6_reass_set_params (timeout_ms, max_reassemblies, max_reassembly_length,
1198                         expire_walk_interval_ms);
1199   vlib_process_signal_event (ip6_reass_main.vlib_main,
1200                              ip6_reass_main.ip6_reass_expire_node_idx,
1201                              IP6_EVENT_CONFIG_CHANGED, 0);
1202   u32 new_nbuckets = ip6_reass_get_nbuckets ();
1203   if (ip6_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1204     {
1205       clib_bihash_48_8_t new_hash;
1206       clib_memset (&new_hash, 0, sizeof (new_hash));
1207       ip6_rehash_cb_ctx ctx;
1208       ctx.failure = 0;
1209       ctx.new_hash = &new_hash;
1210       clib_bihash_init_48_8 (&new_hash, "ip6-reass", new_nbuckets,
1211                              new_nbuckets * 1024);
1212       clib_bihash_foreach_key_value_pair_48_8 (&ip6_reass_main.hash,
1213                                                ip6_rehash_cb, &ctx);
1214       if (ctx.failure)
1215         {
1216           clib_bihash_free_48_8 (&new_hash);
1217           return -1;
1218         }
1219       else
1220         {
1221           clib_bihash_free_48_8 (&ip6_reass_main.hash);
1222           clib_memcpy_fast (&ip6_reass_main.hash, &new_hash,
1223                             sizeof (ip6_reass_main.hash));
1224         }
1225     }
1226   return 0;
1227 }
1228
1229 vnet_api_error_t
1230 ip6_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1231                u32 * expire_walk_interval_ms)
1232 {
1233   *timeout_ms = ip6_reass_main.timeout_ms;
1234   *max_reassemblies = ip6_reass_main.max_reass_n;
1235   *expire_walk_interval_ms = ip6_reass_main.expire_walk_interval_ms;
1236   return 0;
1237 }
1238
1239 static clib_error_t *
1240 ip6_reass_init_function (vlib_main_t * vm)
1241 {
1242   ip6_reass_main_t *rm = &ip6_reass_main;
1243   clib_error_t *error = 0;
1244   u32 nbuckets;
1245   vlib_node_t *node;
1246
1247   rm->vlib_main = vm;
1248   rm->vnet_main = vnet_get_main ();
1249
1250   vec_validate (rm->per_thread_data, vlib_num_workers ());
1251   ip6_reass_per_thread_t *rt;
1252   vec_foreach (rt, rm->per_thread_data)
1253   {
1254     clib_spinlock_init (&rt->lock);
1255     pool_alloc (rt->pool, rm->max_reass_n);
1256   }
1257
1258   node = vlib_get_node_by_name (vm, (u8 *) "ip6-reassembly-expire-walk");
1259   ASSERT (node);
1260   rm->ip6_reass_expire_node_idx = node->index;
1261
1262   ip6_reass_set_params (IP6_REASS_TIMEOUT_DEFAULT_MS,
1263                         IP6_REASS_MAX_REASSEMBLIES_DEFAULT,
1264                         IP6_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT,
1265                         IP6_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1266
1267   nbuckets = ip6_reass_get_nbuckets ();
1268   clib_bihash_init_48_8 (&rm->hash, "ip6-reass", nbuckets, nbuckets * 1024);
1269
1270   node = vlib_get_node_by_name (vm, (u8 *) "ip6-drop");
1271   ASSERT (node);
1272   rm->ip6_drop_idx = node->index;
1273   node = vlib_get_node_by_name (vm, (u8 *) "ip6-icmp-error");
1274   ASSERT (node);
1275   rm->ip6_icmp_error_idx = node->index;
1276
1277   if ((error = vlib_call_init_function (vm, ip_main_init)))
1278     return error;
1279   ip6_register_protocol (IP_PROTOCOL_IPV6_FRAGMENTATION,
1280                          ip6_reass_node.index);
1281
1282   rm->fq_index = vlib_frame_queue_main_init (ip6_reass_node.index, 0);
1283   rm->fq_feature_index =
1284     vlib_frame_queue_main_init (ip6_reass_node_feature.index, 0);
1285
1286   return error;
1287 }
1288
1289 VLIB_INIT_FUNCTION (ip6_reass_init_function);
1290 #endif /* CLIB_MARCH_VARIANT */
1291
1292 static uword
1293 ip6_reass_walk_expired (vlib_main_t * vm,
1294                         vlib_node_runtime_t * node, vlib_frame_t * f)
1295 {
1296   ip6_reass_main_t *rm = &ip6_reass_main;
1297   uword event_type, *event_data = 0;
1298
1299   while (true)
1300     {
1301       vlib_process_wait_for_event_or_clock (vm,
1302                                             (f64) rm->expire_walk_interval_ms
1303                                             / (f64) MSEC_PER_SEC);
1304       event_type = vlib_process_get_events (vm, &event_data);
1305
1306       switch (event_type)
1307         {
1308         case ~0:                /* no events => timeout */
1309           /* nothing to do here */
1310           break;
1311         case IP6_EVENT_CONFIG_CHANGED:
1312           break;
1313         default:
1314           clib_warning ("BUG: event type 0x%wx", event_type);
1315           break;
1316         }
1317       f64 now = vlib_time_now (vm);
1318
1319       ip6_reass_t *reass;
1320       int *pool_indexes_to_free = NULL;
1321
1322       uword thread_index = 0;
1323       int index;
1324       const uword nthreads = vlib_num_workers () + 1;
1325       u32 *vec_icmp_bi = NULL;
1326       for (thread_index = 0; thread_index < nthreads; ++thread_index)
1327         {
1328           ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1329           clib_spinlock_lock (&rt->lock);
1330
1331           vec_reset_length (pool_indexes_to_free);
1332           /* *INDENT-OFF* */
1333           pool_foreach_index (index, rt->pool, ({
1334                                 reass = pool_elt_at_index (rt->pool, index);
1335                                 if (now > reass->last_heard + rm->timeout)
1336                                   {
1337                                     vec_add1 (pool_indexes_to_free, index);
1338                                   }
1339                               }));
1340           /* *INDENT-ON* */
1341           int *i;
1342           /* *INDENT-OFF* */
1343           vec_foreach (i, pool_indexes_to_free)
1344           {
1345             ip6_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1346             u32 icmp_bi = ~0;
1347             vlib_buffer_t *b = vlib_get_buffer (vm, reass->first_bi);
1348             if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1349               {
1350                 if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1351                                         b->trace_index))
1352                   {
1353                     /* the trace is gone, don't trace this buffer anymore */
1354                     b->flags &= ~VLIB_BUFFER_IS_TRACED;
1355                   }
1356               }
1357             ip6_reass_on_timeout (vm, node, rm, reass, &icmp_bi);
1358             if (~0 != icmp_bi)
1359               {
1360                 vec_add1 (vec_icmp_bi, icmp_bi);
1361               }
1362             ip6_reass_free (rm, rt, reass);
1363           }
1364           /* *INDENT-ON* */
1365
1366           clib_spinlock_unlock (&rt->lock);
1367         }
1368
1369       while (vec_len (vec_icmp_bi) > 0)
1370         {
1371           vlib_frame_t *f =
1372             vlib_get_frame_to_node (vm, rm->ip6_icmp_error_idx);
1373           u32 *to_next = vlib_frame_vector_args (f);
1374           u32 n_left_to_next = VLIB_FRAME_SIZE - f->n_vectors;
1375           int trace_frame = 0;
1376           while (vec_len (vec_icmp_bi) > 0 && n_left_to_next > 0)
1377             {
1378               u32 bi = vec_pop (vec_icmp_bi);
1379               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1380               if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1381                 {
1382                   if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1383                                           b->trace_index))
1384                     {
1385                       /* the trace is gone, don't trace this buffer anymore */
1386                       b->flags &= ~VLIB_BUFFER_IS_TRACED;
1387                     }
1388                   else
1389                     {
1390                       trace_frame = 1;
1391                     }
1392                 }
1393               b->error = node->errors[IP6_ERROR_REASS_TIMEOUT];
1394               to_next[0] = bi;
1395               ++f->n_vectors;
1396               to_next += 1;
1397               n_left_to_next -= 1;
1398             }
1399           f->frame_flags |= (trace_frame * VLIB_FRAME_TRACE);
1400           vlib_put_frame_to_node (vm, rm->ip6_icmp_error_idx, f);
1401         }
1402
1403       vec_free (pool_indexes_to_free);
1404       vec_free (vec_icmp_bi);
1405       if (event_data)
1406         {
1407           _vec_len (event_data) = 0;
1408         }
1409     }
1410
1411   return 0;
1412 }
1413
1414 /* *INDENT-OFF* */
1415 VLIB_REGISTER_NODE (ip6_reass_expire_node, static) = {
1416     .function = ip6_reass_walk_expired,
1417     .format_trace = format_ip6_reass_trace,
1418     .type = VLIB_NODE_TYPE_PROCESS,
1419     .name = "ip6-reassembly-expire-walk",
1420
1421     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1422     .error_strings = ip6_reassembly_error_strings,
1423
1424 };
1425 /* *INDENT-ON* */
1426
1427 static u8 *
1428 format_ip6_reass_key (u8 * s, va_list * args)
1429 {
1430   ip6_reass_key_t *key = va_arg (*args, ip6_reass_key_t *);
1431   s = format (s, "xx_id: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1432               key->xx_id, format_ip6_address, &key->src, format_ip6_address,
1433               &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1434   return s;
1435 }
1436
1437 static u8 *
1438 format_ip6_reass (u8 * s, va_list * args)
1439 {
1440   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1441   ip6_reass_t *reass = va_arg (*args, ip6_reass_t *);
1442
1443   s = format (s, "ID: %lu, key: %U\n  first_bi: %u, data_len: %u, "
1444               "last_packet_octet: %u, trace_op_counter: %u\n",
1445               reass->id, format_ip6_reass_key, &reass->key, reass->first_bi,
1446               reass->data_len, reass->last_packet_octet,
1447               reass->trace_op_counter);
1448   u32 bi = reass->first_bi;
1449   u32 counter = 0;
1450   while (~0 != bi)
1451     {
1452       vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1453       vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1454       s = format (s, "  #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1455                   "fragment[%u, %u]\n",
1456                   counter, vnb->ip.reass.range_first,
1457                   vnb->ip.reass.range_last, bi,
1458                   ip6_reass_buffer_get_data_offset (b),
1459                   ip6_reass_buffer_get_data_len (b),
1460                   vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1461       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1462         {
1463           bi = b->next_buffer;
1464         }
1465       else
1466         {
1467           bi = ~0;
1468         }
1469     }
1470   return s;
1471 }
1472
1473 static clib_error_t *
1474 show_ip6_reass (vlib_main_t * vm, unformat_input_t * input,
1475                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1476 {
1477   ip6_reass_main_t *rm = &ip6_reass_main;
1478
1479   vlib_cli_output (vm, "---------------------");
1480   vlib_cli_output (vm, "IP6 reassembly status");
1481   vlib_cli_output (vm, "---------------------");
1482   bool details = false;
1483   if (unformat (input, "details"))
1484     {
1485       details = true;
1486     }
1487
1488   u32 sum_reass_n = 0;
1489   u64 sum_buffers_n = 0;
1490   ip6_reass_t *reass;
1491   uword thread_index;
1492   const uword nthreads = vlib_num_workers () + 1;
1493   for (thread_index = 0; thread_index < nthreads; ++thread_index)
1494     {
1495       ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1496       clib_spinlock_lock (&rt->lock);
1497       if (details)
1498         {
1499           /* *INDENT-OFF* */
1500           pool_foreach (reass, rt->pool, {
1501             vlib_cli_output (vm, "%U", format_ip6_reass, vm, reass);
1502           });
1503           /* *INDENT-ON* */
1504         }
1505       sum_reass_n += rt->reass_n;
1506       clib_spinlock_unlock (&rt->lock);
1507     }
1508   vlib_cli_output (vm, "---------------------");
1509   vlib_cli_output (vm, "Current IP6 reassemblies count: %lu\n",
1510                    (long unsigned) sum_reass_n);
1511   vlib_cli_output (vm, "Maximum configured concurrent IP6 reassemblies per "
1512                    "worker-thread: %lu\n", (long unsigned) rm->max_reass_n);
1513   vlib_cli_output (vm, "Buffers in use: %lu\n",
1514                    (long unsigned) sum_buffers_n);
1515   return 0;
1516 }
1517
1518 /* *INDENT-OFF* */
1519 VLIB_CLI_COMMAND (show_ip6_reassembly_cmd, static) = {
1520     .path = "show ip6-reassembly",
1521     .short_help = "show ip6-reassembly [details]",
1522     .function = show_ip6_reass,
1523 };
1524 /* *INDENT-ON* */
1525
1526 #ifndef CLIB_MARCH_VARIANT
1527 vnet_api_error_t
1528 ip6_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1529 {
1530   return vnet_feature_enable_disable ("ip6-unicast", "ip6-reassembly-feature",
1531                                       sw_if_index, enable_disable, 0, 0);
1532 }
1533 #endif /* CLIB_MARCH_VARIANT */
1534
1535 #define foreach_ip6_reassembly_handoff_error                       \
1536 _(CONGESTION_DROP, "congestion drop")
1537
1538
1539 typedef enum
1540 {
1541 #define _(sym,str) IP6_REASSEMBLY_HANDOFF_ERROR_##sym,
1542   foreach_ip6_reassembly_handoff_error
1543 #undef _
1544     IP6_REASSEMBLY_HANDOFF_N_ERROR,
1545 } ip6_reassembly_handoff_error_t;
1546
1547 static char *ip6_reassembly_handoff_error_strings[] = {
1548 #define _(sym,string) string,
1549   foreach_ip6_reassembly_handoff_error
1550 #undef _
1551 };
1552
1553 typedef struct
1554 {
1555   u32 next_worker_index;
1556 } ip6_reassembly_handoff_trace_t;
1557
1558 static u8 *
1559 format_ip6_reassembly_handoff_trace (u8 * s, va_list * args)
1560 {
1561   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1562   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1563   ip6_reassembly_handoff_trace_t *t =
1564     va_arg (*args, ip6_reassembly_handoff_trace_t *);
1565
1566   s =
1567     format (s, "ip6-reassembly-handoff: next-worker %d",
1568             t->next_worker_index);
1569
1570   return s;
1571 }
1572
1573 always_inline uword
1574 ip6_reassembly_handoff_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
1575                                vlib_frame_t * frame, bool is_feature)
1576 {
1577   ip6_reass_main_t *rm = &ip6_reass_main;
1578
1579   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1580   u32 n_enq, n_left_from, *from;
1581   u16 thread_indices[VLIB_FRAME_SIZE], *ti;
1582   u32 fq_index;
1583
1584   from = vlib_frame_vector_args (frame);
1585   n_left_from = frame->n_vectors;
1586   vlib_get_buffers (vm, from, bufs, n_left_from);
1587
1588   b = bufs;
1589   ti = thread_indices;
1590
1591   fq_index = (is_feature) ? rm->fq_feature_index : rm->fq_index;
1592
1593   while (n_left_from > 0)
1594     {
1595       ti[0] =
1596         (is_feature) ? vnet_buffer (b[0])->ip.
1597         reass.owner_feature_thread_index : vnet_buffer (b[0])->ip.
1598         reass.owner_thread_index;
1599
1600       if (PREDICT_FALSE
1601           ((node->flags & VLIB_NODE_FLAG_TRACE)
1602            && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
1603         {
1604           ip6_reassembly_handoff_trace_t *t =
1605             vlib_add_trace (vm, node, b[0], sizeof (*t));
1606           t->next_worker_index = ti[0];
1607         }
1608
1609       n_left_from -= 1;
1610       ti += 1;
1611       b += 1;
1612     }
1613   n_enq =
1614     vlib_buffer_enqueue_to_thread (vm, fq_index, from, thread_indices,
1615                                    frame->n_vectors, 1);
1616
1617   if (n_enq < frame->n_vectors)
1618     vlib_node_increment_counter (vm, node->node_index,
1619                                  IP6_REASSEMBLY_HANDOFF_ERROR_CONGESTION_DROP,
1620                                  frame->n_vectors - n_enq);
1621   return frame->n_vectors;
1622 }
1623
1624 VLIB_NODE_FN (ip6_reassembly_handoff_node) (vlib_main_t * vm,
1625                                             vlib_node_runtime_t * node,
1626                                             vlib_frame_t * frame)
1627 {
1628   return ip6_reassembly_handoff_inline (vm, node, frame,
1629                                         false /* is_feature */ );
1630 }
1631
1632 /* *INDENT-OFF* */
1633 VLIB_REGISTER_NODE (ip6_reassembly_handoff_node) = {
1634   .name = "ip6-reassembly-handoff",
1635   .vector_size = sizeof (u32),
1636   .n_errors = ARRAY_LEN(ip6_reassembly_handoff_error_strings),
1637   .error_strings = ip6_reassembly_handoff_error_strings,
1638   .format_trace = format_ip6_reassembly_handoff_trace,
1639
1640   .n_next_nodes = 1,
1641
1642   .next_nodes = {
1643     [0] = "error-drop",
1644   },
1645 };
1646
1647
1648 VLIB_NODE_FN (ip6_reassembly_feature_handoff_node) (vlib_main_t * vm,
1649                                vlib_node_runtime_t * node, vlib_frame_t * frame)
1650 {
1651   return ip6_reassembly_handoff_inline (vm, node, frame, true /* is_feature */ );
1652 }
1653
1654
1655 /* *INDENT-OFF* */
1656 VLIB_REGISTER_NODE (ip6_reassembly_feature_handoff_node) = {
1657   .name = "ip6-reass-feature-hoff",
1658   .vector_size = sizeof (u32),
1659   .n_errors = ARRAY_LEN(ip6_reassembly_handoff_error_strings),
1660   .error_strings = ip6_reassembly_handoff_error_strings,
1661   .format_trace = format_ip6_reassembly_handoff_trace,
1662
1663   .n_next_nodes = 1,
1664
1665   .next_nodes = {
1666     [0] = "error-drop",
1667   },
1668 };
1669 /* *INDENT-ON* */
1670
1671 /*
1672  * fd.io coding-style-patch-verification: ON
1673  *
1674  * Local Variables:
1675  * eval: (c-set-style "gnu")
1676  * End:
1677  */