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 static vlib_node_registration_t ip6_reass_node;
  36
  37 typedef struct
  38 {
  39   union
  40   {
  41     struct
  42     {
  43       ip6_address_t src;
  44       ip6_address_t dst;
  45       // align by making this 4 octets even though its a 2 octets field
  46       u32 xx_id;
  47       // align by making this 4 octets even though its a 2 octets field
  48       u32 frag_id;
  49       // align by making this 4 octets even though its a 1 octet field
  50       u32 proto;
  51       u32 unused;
  52     };
  53     u64 as_u64[6];
  54   };
  55 } ip6_reass_key_t;
  56
  57 always_inline u32
  58 ip6_reass_buffer_get_data_offset_no_check (vlib_buffer_t * b)
  59 {
  60   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  61   return vnb->ip.reass.range_first - vnb->ip.reass.fragment_first;
  62 }
  63
  64 always_inline u32
  65 ip6_reass_buffer_get_data_offset (vlib_buffer_t * b)
  66 {
  67   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  68   ASSERT (vnb->ip.reass.range_first >= vnb->ip.reass.fragment_first);
  69   return ip6_reass_buffer_get_data_offset_no_check (b);
  70 }
  71
  72 always_inline u16
  73 ip6_reass_buffer_get_data_len_no_check (vlib_buffer_t * b)
  74 {
  75   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  76   return clib_min (vnb->ip.reass.range_last, vnb->ip.reass.fragment_last) -
  77     (vnb->ip.reass.fragment_first + ip6_reass_buffer_get_data_offset (b)) + 1;
  78 }
  79
  80 always_inline u16
  81 ip6_reass_buffer_get_data_len (vlib_buffer_t * b)
  82 {
  83   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
  84   ASSERT (vnb->ip.reass.range_last > vnb->ip.reass.fragment_first);
  85   return ip6_reass_buffer_get_data_len_no_check (b);
  86 }
  87
  88 typedef struct
  89 {
  90   // hash table key
  91   ip6_reass_key_t key;
  92   // time when last packet was received
  93   f64 last_heard;
  94   // internal id of this reassembly
  95   u64 id;
  96   // buffer index of first buffer in this reassembly context
  97   u32 first_bi;
  98   // last octet of packet, ~0 until fragment without more_fragments arrives
  99   u32 last_packet_octet;
 100   // length of data collected so far
 101   u32 data_len;
 102   // trace operation counter
 103   u32 trace_op_counter;
 104   // next index - used by non-feature node
 105   u8 next_index;
 106   // minimum fragment length for this reassembly - used to estimate MTU
 107   u16 min_fragment_length;
 108 } ip6_reass_t;
 109
 110 typedef struct
 111 {
 112   ip6_reass_t *pool;
 113   u32 reass_n;
 114   u32 buffers_n;
 115   u32 id_counter;
 116   clib_spinlock_t lock;
 117 } ip6_reass_per_thread_t;
 118
 119 typedef struct
 120 {
 121   // IPv6 config
 122   u32 timeout_ms;
 123   f64 timeout;
 124   u32 expire_walk_interval_ms;
 125   u32 max_reass_n;
 126
 127   // IPv6 runtime
 128   clib_bihash_48_8_t hash;
 129
 130   // per-thread data
 131   ip6_reass_per_thread_t *per_thread_data;
 132
 133   // convenience
 134   vlib_main_t *vlib_main;
 135   vnet_main_t *vnet_main;
 136
 137   // node index of ip6-drop node
 138   u32 ip6_drop_idx;
 139   u32 ip6_icmp_error_idx;
 140   u32 ip6_reass_expire_node_idx;
 141
 142 } ip6_reass_main_t;
 143
 144 ip6_reass_main_t ip6_reass_main;
 145
 146 typedef enum
 147 {
 148   IP6_REASSEMBLY_NEXT_INPUT,
 149   IP6_REASSEMBLY_NEXT_DROP,
 150   IP6_REASSEMBLY_NEXT_ICMP_ERROR,
 151   IP6_REASSEMBLY_N_NEXT,
 152 } ip6_reass_next_t;
 153
 154 typedef enum
 155 {
 156   RANGE_NEW,
 157   RANGE_OVERLAP,
 158   ICMP_ERROR_RT_EXCEEDED,
 159   ICMP_ERROR_FL_TOO_BIG,
 160   ICMP_ERROR_FL_NOT_MULT_8,
 161   FINALIZE,
 162 } ip6_reass_trace_operation_e;
 163
 164 typedef struct
 165 {
 166   u16 range_first;
 167   u16 range_last;
 168   u32 range_bi;
 169   i32 data_offset;
 170   u32 data_len;
 171   u32 first_bi;
 172 } ip6_reass_range_trace_t;
 173
 174 typedef struct
 175 {
 176   ip6_reass_trace_operation_e action;
 177   u32 reass_id;
 178   ip6_reass_range_trace_t trace_range;
 179   u32 size_diff;
 180   u32 op_id;
 181   u32 fragment_first;
 182   u32 fragment_last;
 183   u32 total_data_len;
 184 } ip6_reass_trace_t;
 185
 186 static void
 187 ip6_reass_trace_details (vlib_main_t * vm, u32 bi,
 188                          ip6_reass_range_trace_t * trace)
 189 {
 190   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 191   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 192   trace->range_first = vnb->ip.reass.range_first;
 193   trace->range_last = vnb->ip.reass.range_last;
 194   trace->data_offset = ip6_reass_buffer_get_data_offset_no_check (b);
 195   trace->data_len = ip6_reass_buffer_get_data_len_no_check (b);
 196   trace->range_bi = bi;
 197 }
 198
 199 static u8 *
 200 format_ip6_reass_range_trace (u8 * s, va_list * args)
 201 {
 202   ip6_reass_range_trace_t *trace = va_arg (*args, ip6_reass_range_trace_t *);
 203   s = format (s, "range: [%u, %u], off %d, len %u, bi %u", trace->range_first,
 204               trace->range_last, trace->data_offset, trace->data_len,
 205               trace->range_bi);
 206   return s;
 207 }
 208
 209 static u8 *
 210 format_ip6_reass_trace (u8 * s, va_list * args)
 211 {
 212   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
 213   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
 214   ip6_reass_trace_t *t = va_arg (*args, ip6_reass_trace_t *);
 215   s = format (s, "reass id: %u, op id: %u ", t->reass_id, t->op_id);
 216   u32 indent = format_get_indent (s);
 217   s = format (s, "first bi: %u, data len: %u, ip/fragment[%u, %u]",
 218               t->trace_range.first_bi, t->total_data_len, t->fragment_first,
 219               t->fragment_last);
 220   switch (t->action)
 221     {
 222     case RANGE_NEW:
 223       s = format (s, "\n%Unew %U", format_white_space, indent,
 224                   format_ip6_reass_range_trace, &t->trace_range);
 225       break;
 226     case RANGE_OVERLAP:
 227       s = format (s, "\n%Uoverlap %U", format_white_space, indent,
 228                   format_ip6_reass_range_trace, &t->trace_range);
 229       break;
 230     case ICMP_ERROR_FL_TOO_BIG:
 231       s = format (s, "\n%Uicmp-error - frag_len > 65535 %U",
 232                   format_white_space, indent, format_ip6_reass_range_trace,
 233                   &t->trace_range);
 234       break;
 235     case ICMP_ERROR_FL_NOT_MULT_8:
 236       s = format (s, "\n%Uicmp-error - frag_len mod 8 != 0 %U",
 237                   format_white_space, indent, format_ip6_reass_range_trace,
 238                   &t->trace_range);
 239       break;
 240     case ICMP_ERROR_RT_EXCEEDED:
 241       s = format (s, "\n%Uicmp-error - reassembly time exceeded",
 242                   format_white_space, indent);
 243       break;
 244     case FINALIZE:
 245       s = format (s, "\n%Ufinalize reassembly", format_white_space, indent);
 246       break;
 247     }
 248   return s;
 249 }
 250
 251 static void
 252 ip6_reass_add_trace (vlib_main_t * vm, vlib_node_runtime_t * node,
 253                      ip6_reass_main_t * rm, ip6_reass_t * reass,
 254                      u32 bi, ip6_reass_trace_operation_e action,
 255                      u32 size_diff)
 256 {
 257   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 258   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 259   if (pool_is_free_index (vm->trace_main.trace_buffer_pool, b->trace_index))
 260     {
 261       // this buffer's trace is gone
 262       b->flags &= ~VLIB_BUFFER_IS_TRACED;
 263       return;
 264     }
 265   ip6_reass_trace_t *t = vlib_add_trace (vm, node, b, sizeof (t[0]));
 266   t->reass_id = reass->id;
 267   t->action = action;
 268   ip6_reass_trace_details (vm, bi, &t->trace_range);
 269   t->size_diff = size_diff;
 270   t->op_id = reass->trace_op_counter;
 271   ++reass->trace_op_counter;
 272   t->fragment_first = vnb->ip.reass.fragment_first;
 273   t->fragment_last = vnb->ip.reass.fragment_last;
 274   t->trace_range.first_bi = reass->first_bi;
 275   t->total_data_len = reass->data_len;
 276 #if 0
 277   static u8 *s = NULL;
 278   s = format (s, "%U", format_ip6_reass_trace, NULL, NULL, t);
 279   printf ("%.*s\n", vec_len (s), s);
 280   fflush (stdout);
 281   vec_reset_length (s);
 282 #endif
 283 }
 284
 285 always_inline void
 286 ip6_reass_free (ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 287                 ip6_reass_t * reass)
 288 {
 289   clib_bihash_kv_48_8_t kv;
 290   kv.key[0] = reass->key.as_u64[0];
 291   kv.key[1] = reass->key.as_u64[1];
 292   kv.key[2] = reass->key.as_u64[2];
 293   kv.key[3] = reass->key.as_u64[3];
 294   kv.key[4] = reass->key.as_u64[4];
 295   kv.key[5] = reass->key.as_u64[5];
 296   clib_bihash_add_del_48_8 (&rm->hash, &kv, 0);
 297   pool_put (rt->pool, reass);
 298   --rt->reass_n;
 299 }
 300
 301 always_inline void
 302 ip6_reass_drop_all (vlib_main_t * vm, ip6_reass_main_t * rm,
 303                     ip6_reass_t * reass, u32 ** vec_drop_bi)
 304 {
 305   u32 range_bi = reass->first_bi;
 306   vlib_buffer_t *range_b;
 307   vnet_buffer_opaque_t *range_vnb;
 308   while (~0 != range_bi)
 309     {
 310       range_b = vlib_get_buffer (vm, range_bi);
 311       range_vnb = vnet_buffer (range_b);
 312       u32 bi = range_bi;
 313       while (~0 != bi)
 314         {
 315           vec_add1 (*vec_drop_bi, bi);
 316           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 317           if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 318             {
 319               bi = b->next_buffer;
 320               b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 321             }
 322           else
 323             {
 324               bi = ~0;
 325             }
 326         }
 327       range_bi = range_vnb->ip.reass.next_range_bi;
 328     }
 329 }
 330
 331 always_inline void
 332 ip6_reass_on_timeout (vlib_main_t * vm, vlib_node_runtime_t * node,
 333                       ip6_reass_main_t * rm, ip6_reass_t * reass,
 334                       u32 * icmp_bi, u32 ** vec_timeout)
 335 {
 336   if (~0 == reass->first_bi)
 337     {
 338       return;
 339     }
 340   vlib_buffer_t *b = vlib_get_buffer (vm, reass->first_bi);
 341   if (0 == vnet_buffer (b)->ip.reass.fragment_first)
 342     {
 343       *icmp_bi = reass->first_bi;
 344       if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
 345         {
 346           ip6_reass_add_trace (vm, node, rm, reass, reass->first_bi,
 347                                ICMP_ERROR_RT_EXCEEDED, 0);
 348         }
 349       // fragment with offset zero received - send icmp message back
 350       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 351         {
 352           // separate first buffer from chain and steer it towards icmp node
 353           b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 354           reass->first_bi = b->next_buffer;
 355         }
 356       else
 357         {
 358           reass->first_bi = vnet_buffer (b)->ip.reass.next_range_bi;
 359         }
 360       icmp6_error_set_vnet_buffer (b, ICMP6_time_exceeded,
 361                                    ICMP6_time_exceeded_fragment_reassembly_time_exceeded,
 362                                    0);
 363     }
 364   ip6_reass_drop_all (vm, rm, reass, vec_timeout);
 365 }
 366
 367 always_inline ip6_reass_t *
 368 ip6_reass_find_or_create (vlib_main_t * vm, vlib_node_runtime_t * node,
 369                           ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 370                           ip6_reass_key_t * k, u32 * icmp_bi,
 371                           u32 ** vec_timeout)
 372 {
 373   ip6_reass_t *reass = NULL;
 374   f64 now = vlib_time_now (rm->vlib_main);
 375   clib_bihash_kv_48_8_t kv, value;
 376   kv.key[0] = k->as_u64[0];
 377   kv.key[1] = k->as_u64[1];
 378   kv.key[2] = k->as_u64[2];
 379   kv.key[3] = k->as_u64[3];
 380   kv.key[4] = k->as_u64[4];
 381   kv.key[5] = k->as_u64[5];
 382
 383   if (!clib_bihash_search_48_8 (&rm->hash, &kv, &value))
 384     {
 385       reass = pool_elt_at_index (rt->pool, value.value);
 386       if (now > reass->last_heard + rm->timeout)
 387         {
 388           ip6_reass_on_timeout (vm, node, rm, reass, icmp_bi, vec_timeout);
 389           ip6_reass_free (rm, rt, reass);
 390           reass = NULL;
 391         }
 392     }
 393
 394   if (reass)
 395     {
 396       reass->last_heard = now;
 397       return reass;
 398     }
 399
 400   if (rt->reass_n >= rm->max_reass_n)
 401     {
 402       reass = NULL;
 403       return reass;
 404     }
 405   else
 406     {
 407       pool_get (rt->pool, reass);
 408       memset (reass, 0, sizeof (*reass));
 409       reass->id =
 410         ((u64) os_get_thread_index () * 1000000000) + rt->id_counter;
 411       ++rt->id_counter;
 412       reass->first_bi = ~0;
 413       reass->last_packet_octet = ~0;
 414       reass->data_len = 0;
 415       ++rt->reass_n;
 416     }
 417
 418   reass->key.as_u64[0] = kv.key[0] = k->as_u64[0];
 419   reass->key.as_u64[1] = kv.key[1] = k->as_u64[1];
 420   reass->key.as_u64[2] = kv.key[2] = k->as_u64[2];
 421   reass->key.as_u64[3] = kv.key[3] = k->as_u64[3];
 422   reass->key.as_u64[4] = kv.key[4] = k->as_u64[4];
 423   reass->key.as_u64[5] = kv.key[5] = k->as_u64[5];
 424   kv.value = reass - rt->pool;
 425   reass->last_heard = now;
 426
 427   if (clib_bihash_add_del_48_8 (&rm->hash, &kv, 1))
 428     {
 429       ip6_reass_free (rm, rt, reass);
 430       reass = NULL;
 431     }
 432
 433   return reass;
 434 }
 435
 436 always_inline void
 437 ip6_reass_finalize (vlib_main_t * vm, vlib_node_runtime_t * node,
 438                     ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 439                     ip6_reass_t * reass, u32 * bi0, u32 * next0,
 440                     u32 * error0, u32 ** vec_drop_compress, bool is_feature)
 441 {
 442   ASSERT (~0 != reass->first_bi);
 443   *bi0 = reass->first_bi;
 444   *error0 = IP6_ERROR_NONE;
 445   ip6_frag_hdr_t *frag_hdr;
 446   vlib_buffer_t *last_b = NULL;
 447   u32 sub_chain_bi = reass->first_bi;
 448   u32 total_length = 0;
 449   u32 buf_cnt = 0;
 450   u32 dropped_cnt = 0;
 451   do
 452     {
 453       u32 tmp_bi = sub_chain_bi;
 454       vlib_buffer_t *tmp = vlib_get_buffer (vm, tmp_bi);
 455       u32 data_len = ip6_reass_buffer_get_data_len (tmp);
 456       u32 trim_front = vnet_buffer (tmp)->ip.reass.ip6_frag_hdr_offset +
 457         sizeof (*frag_hdr) + ip6_reass_buffer_get_data_offset (tmp);
 458       u32 trim_end =
 459         vlib_buffer_length_in_chain (vm, tmp) - trim_front - data_len;
 460       if (tmp_bi == reass->first_bi)
 461         {
 462           /* first buffer - keep ip6 header */
 463           ASSERT (0 == ip6_reass_buffer_get_data_offset (tmp));
 464           trim_front = 0;
 465           trim_end = vlib_buffer_length_in_chain (vm, tmp) - data_len -
 466             (vnet_buffer (tmp)->ip.reass.ip6_frag_hdr_offset +
 467              sizeof (*frag_hdr));
 468           ASSERT (vlib_buffer_length_in_chain (vm, tmp) - trim_end > 0);
 469         }
 470       u32 keep_data =
 471         vlib_buffer_length_in_chain (vm, tmp) - trim_front - trim_end;
 472       while (1)
 473         {
 474           ++buf_cnt;
 475           if (trim_front)
 476             {
 477               if (trim_front > tmp->current_length)
 478                 {
 479                   /* drop whole buffer */
 480                   vec_add1 (*vec_drop_compress, tmp_bi);
 481                   ++dropped_cnt;
 482                   trim_front -= tmp->current_length;
 483                   ASSERT (tmp->flags & VLIB_BUFFER_NEXT_PRESENT);
 484                   tmp->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 485                   tmp_bi = tmp->next_buffer;
 486                   tmp = vlib_get_buffer (vm, tmp_bi);
 487                   continue;
 488                 }
 489               else
 490                 {
 491                   vlib_buffer_advance (tmp, trim_front);
 492                   trim_front = 0;
 493                 }
 494             }
 495           if (keep_data)
 496             {
 497               if (last_b)
 498                 {
 499                   last_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
 500                   last_b->next_buffer = tmp_bi;
 501                 }
 502               last_b = tmp;
 503               if (keep_data <= tmp->current_length)
 504                 {
 505                   tmp->current_length = keep_data;
 506                   keep_data = 0;
 507                 }
 508               else
 509                 {
 510                   keep_data -= tmp->current_length;
 511                   ASSERT (tmp->flags & VLIB_BUFFER_NEXT_PRESENT);
 512                 }
 513               total_length += tmp->current_length;
 514             }
 515           else
 516             {
 517               vec_add1 (*vec_drop_compress, tmp_bi);
 518               ASSERT (reass->first_bi != tmp_bi);
 519               ++dropped_cnt;
 520             }
 521           if (tmp->flags & VLIB_BUFFER_NEXT_PRESENT)
 522             {
 523               tmp_bi = tmp->next_buffer;
 524               tmp = vlib_get_buffer (vm, tmp->next_buffer);
 525             }
 526           else
 527             {
 528               break;
 529             }
 530         }
 531       sub_chain_bi =
 532         vnet_buffer (vlib_get_buffer (vm, sub_chain_bi))->ip.
 533         reass.next_range_bi;
 534     }
 535   while (~0 != sub_chain_bi);
 536
 537   ASSERT (last_b != NULL);
 538   last_b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
 539   vlib_buffer_t *first_b = vlib_get_buffer (vm, reass->first_bi);
 540   ASSERT (total_length >= first_b->current_length);
 541   total_length -= first_b->current_length;
 542   first_b->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
 543   first_b->total_length_not_including_first_buffer = total_length;
 544   // drop fragment header
 545   vnet_buffer_opaque_t *first_b_vnb = vnet_buffer (first_b);
 546   ip6_header_t *ip = vlib_buffer_get_current (first_b);
 547   u16 ip6_frag_hdr_offset = first_b_vnb->ip.reass.ip6_frag_hdr_offset;
 548   ip6_ext_header_t *prev_hdr;
 549   ip6_ext_header_find_t (ip, prev_hdr, frag_hdr,
 550                          IP_PROTOCOL_IPV6_FRAGMENTATION);
 551   if (prev_hdr)
 552     {
 553       prev_hdr->next_hdr = frag_hdr->next_hdr;
 554     }
 555   else
 556     {
 557       ip->protocol = frag_hdr->next_hdr;
 558     }
 559   ASSERT ((u8 *) frag_hdr - (u8 *) ip == ip6_frag_hdr_offset);
 560   memmove (frag_hdr, (u8 *) frag_hdr + sizeof (*frag_hdr),
 561            first_b->current_length - ip6_frag_hdr_offset -
 562            sizeof (ip6_frag_hdr_t));
 563   first_b->current_length -= sizeof (*frag_hdr);
 564   ip->payload_length =
 565     clib_host_to_net_u16 (total_length + first_b->current_length -
 566                           sizeof (*ip));
 567   vlib_buffer_chain_compress (vm, first_b, vec_drop_compress);
 568   if (PREDICT_FALSE (first_b->flags & VLIB_BUFFER_IS_TRACED))
 569     {
 570       ip6_reass_add_trace (vm, node, rm, reass, reass->first_bi, FINALIZE, 0);
 571 #if 0
 572       // following code does a hexdump of packet fragments to stdout ...
 573       do
 574         {
 575           u32 bi = reass->first_bi;
 576           u8 *s = NULL;
 577           while (~0 != bi)
 578             {
 579               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 580               s = format (s, "%u: %U\n", bi, format_hexdump,
 581                           vlib_buffer_get_current (b), b->current_length);
 582               if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
 583                 {
 584                   bi = b->next_buffer;
 585                 }
 586               else
 587                 {
 588                   break;
 589                 }
 590             }
 591           printf ("%.*s\n", vec_len (s), s);
 592           fflush (stdout);
 593           vec_free (s);
 594         }
 595       while (0);
 596 #endif
 597     }
 598   if (is_feature)
 599     {
 600       *next0 = IP6_REASSEMBLY_NEXT_INPUT;
 601     }
 602   else
 603     {
 604       *next0 = reass->next_index;
 605     }
 606   vnet_buffer (first_b)->ip.reass.estimated_mtu = reass->min_fragment_length;
 607   ip6_reass_free (rm, rt, reass);
 608   reass = NULL;
 609 }
 610
 611 always_inline u32
 612 ip6_reass_get_buffer_chain_length (vlib_main_t * vm, vlib_buffer_t * b)
 613 {
 614   u32 len = 0;
 615   while (b)
 616     {
 617       ++len;
 618       if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
 619         {
 620           b = vlib_get_buffer (vm, b->next_buffer);
 621         }
 622       else
 623         {
 624           break;
 625         }
 626     }
 627   return len;
 628 }
 629
 630 always_inline void
 631 ip6_reass_insert_range_in_chain (vlib_main_t * vm, ip6_reass_main_t * rm,
 632                                  ip6_reass_per_thread_t * rt,
 633                                  ip6_reass_t * reass, u32 prev_range_bi,
 634                                  u32 new_next_bi)
 635 {
 636
 637   vlib_buffer_t *new_next_b = vlib_get_buffer (vm, new_next_bi);
 638   vnet_buffer_opaque_t *new_next_vnb = vnet_buffer (new_next_b);
 639   if (~0 != prev_range_bi)
 640     {
 641       vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_range_bi);
 642       vnet_buffer_opaque_t *prev_vnb = vnet_buffer (prev_b);
 643       new_next_vnb->ip.reass.next_range_bi = prev_vnb->ip.reass.next_range_bi;
 644       prev_vnb->ip.reass.next_range_bi = new_next_bi;
 645     }
 646   else
 647     {
 648       if (~0 != reass->first_bi)
 649         {
 650           new_next_vnb->ip.reass.next_range_bi = reass->first_bi;
 651         }
 652       reass->first_bi = new_next_bi;
 653     }
 654   reass->data_len += ip6_reass_buffer_get_data_len (new_next_b);
 655   rt->buffers_n += ip6_reass_get_buffer_chain_length (vm, new_next_b);
 656 }
 657
 658 always_inline void
 659 ip6_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
 660                   ip6_reass_main_t * rm, ip6_reass_per_thread_t * rt,
 661                   ip6_reass_t * reass, u32 * bi0, u32 * next0,
 662                   u32 * error0, ip6_frag_hdr_t * frag_hdr,
 663                   u32 ** vec_drop_overlap, u32 ** vec_drop_compress,
 664                   bool is_feature)
 665 {
 666   int consumed = 0;
 667   vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
 668   vnet_buffer_opaque_t *fvnb = vnet_buffer (fb);
 669   fvnb->ip.reass.ip6_frag_hdr_offset =
 670     (u8 *) frag_hdr - (u8 *) vlib_buffer_get_current (fb);
 671   ip6_header_t *fip = vlib_buffer_get_current (fb);
 672   ASSERT (fb->current_length > sizeof (*fip));
 673   ASSERT (fvnb->ip.reass.ip6_frag_hdr_offset > 0 &&
 674           fvnb->ip.reass.ip6_frag_hdr_offset < fb->current_length);
 675   u32 fragment_first = fvnb->ip.reass.fragment_first =
 676     ip6_frag_hdr_offset_bytes (frag_hdr);
 677   u32 fragment_length =
 678     vlib_buffer_length_in_chain (vm, fb) -
 679     (fvnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 680   u32 fragment_last = fvnb->ip.reass.fragment_last =
 681     fragment_first + fragment_length - 1;
 682   int more_fragments = ip6_frag_hdr_more (frag_hdr);
 683   u32 candidate_range_bi = reass->first_bi;
 684   u32 prev_range_bi = ~0;
 685   fvnb->ip.reass.range_first = fragment_first;
 686   fvnb->ip.reass.range_last = fragment_last;
 687   fvnb->ip.reass.next_range_bi = ~0;
 688   if (!more_fragments)
 689     {
 690       reass->last_packet_octet = fragment_last;
 691     }
 692   if (~0 == reass->first_bi)
 693     {
 694       // starting a new reassembly
 695       ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
 696                                        *bi0);
 697       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 698         {
 699           ip6_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
 700         }
 701       reass->min_fragment_length = clib_net_to_host_u16 (fip->payload_length);
 702       *bi0 = ~0;
 703       return;
 704     }
 705   reass->min_fragment_length =
 706     clib_min (clib_net_to_host_u16 (fip->payload_length),
 707               fvnb->ip.reass.estimated_mtu);
 708   while (~0 != candidate_range_bi)
 709     {
 710       vlib_buffer_t *candidate_b = vlib_get_buffer (vm, candidate_range_bi);
 711       vnet_buffer_opaque_t *candidate_vnb = vnet_buffer (candidate_b);
 712       if (fragment_first > candidate_vnb->ip.reass.range_last)
 713         {
 714           // this fragments starts after candidate range
 715           prev_range_bi = candidate_range_bi;
 716           candidate_range_bi = candidate_vnb->ip.reass.next_range_bi;
 717           if (candidate_vnb->ip.reass.range_last < fragment_last &&
 718               ~0 == candidate_range_bi)
 719             {
 720               // special case - this fragment falls beyond all known ranges
 721               ip6_reass_insert_range_in_chain (vm, rm, rt, reass,
 722                                                prev_range_bi, *bi0);
 723               consumed = 1;
 724               break;
 725             }
 726           continue;
 727         }
 728       if (fragment_last < candidate_vnb->ip.reass.range_first)
 729         {
 730           // this fragment ends before candidate range without any overlap
 731           ip6_reass_insert_range_in_chain (vm, rm, rt, reass, prev_range_bi,
 732                                            *bi0);
 733           consumed = 1;
 734         }
 735       else if (fragment_first == candidate_vnb->ip.reass.range_first &&
 736                fragment_last == candidate_vnb->ip.reass.range_last)
 737         {
 738           // duplicate fragment - ignore
 739         }
 740       else
 741         {
 742           // overlapping fragment - not allowed by RFC 8200
 743           ip6_reass_drop_all (vm, rm, reass, vec_drop_overlap);
 744           ip6_reass_free (rm, rt, reass);
 745           if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 746             {
 747               ip6_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_OVERLAP,
 748                                    0);
 749             }
 750           *next0 = IP6_REASSEMBLY_NEXT_DROP;
 751           *error0 = IP6_ERROR_REASS_OVERLAPPING_FRAGMENT;
 752         }
 753       break;
 754     }
 755   if (consumed)
 756     {
 757       if (PREDICT_FALSE (fb->flags & VLIB_BUFFER_IS_TRACED))
 758         {
 759           ip6_reass_add_trace (vm, node, rm, reass, *bi0, RANGE_NEW, 0);
 760         }
 761     }
 762   if (~0 != reass->last_packet_octet &&
 763       reass->data_len == reass->last_packet_octet + 1)
 764     {
 765       ip6_reass_finalize (vm, node, rm, rt, reass, bi0, next0, error0,
 766                           vec_drop_compress, is_feature);
 767     }
 768   else
 769     {
 770       if (consumed)
 771         {
 772           *bi0 = ~0;
 773         }
 774       else
 775         {
 776           *next0 = IP6_REASSEMBLY_NEXT_DROP;
 777           ;
 778           *error0 = IP6_ERROR_REASS_DUPLICATE_FRAGMENT;
 779         }
 780     }
 781 }
 782
 783 always_inline bool
 784 ip6_reass_verify_upper_layer_present (vlib_node_runtime_t * node,
 785                                       vlib_buffer_t * b,
 786                                       ip6_frag_hdr_t * frag_hdr)
 787 {
 788   ip6_ext_header_t *tmp = (ip6_ext_header_t *) frag_hdr;
 789   while (ip6_ext_hdr (tmp->next_hdr))
 790     {
 791       tmp = ip6_ext_next_header (tmp);
 792     }
 793   if (IP_PROTOCOL_IP6_NONXT == tmp->next_hdr)
 794     {
 795       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 796                                    ICMP6_parameter_problem_first_fragment_has_incomplete_header_chain,
 797                                    0);
 798       b->error = node->errors[IP6_ERROR_REASS_MISSING_UPPER];
 799
 800       return false;
 801     }
 802   return true;
 803 }
 804
 805 always_inline bool
 806 ip6_reass_verify_fragment_multiple_8 (vlib_main_t * vm,
 807                                       vlib_node_runtime_t * node,
 808                                       vlib_buffer_t * b,
 809                                       ip6_frag_hdr_t * frag_hdr)
 810 {
 811   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 812   ip6_header_t *ip = vlib_buffer_get_current (b);
 813   int more_fragments = ip6_frag_hdr_more (frag_hdr);
 814   u32 fragment_length =
 815     vlib_buffer_length_in_chain (vm, b) -
 816     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 817   if (more_fragments && 0 != fragment_length % 8)
 818     {
 819       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 820                                    ICMP6_parameter_problem_erroneous_header_field,
 821                                    (u8 *) & ip->payload_length - (u8 *) ip);
 822       return false;
 823     }
 824   return true;
 825 }
 826
 827 always_inline bool
 828 ip6_reass_verify_packet_size_lt_64k (vlib_main_t * vm,
 829                                      vlib_node_runtime_t * node,
 830                                      vlib_buffer_t * b,
 831                                      ip6_frag_hdr_t * frag_hdr)
 832 {
 833   vnet_buffer_opaque_t *vnb = vnet_buffer (b);
 834   u32 fragment_first = ip6_frag_hdr_offset_bytes (frag_hdr);
 835   u32 fragment_length =
 836     vlib_buffer_length_in_chain (vm, b) -
 837     (vnb->ip.reass.ip6_frag_hdr_offset + sizeof (*frag_hdr));
 838   if (fragment_first + fragment_length > 65535)
 839     {
 840       ip6_header_t *ip0 = vlib_buffer_get_current (b);
 841       icmp6_error_set_vnet_buffer (b, ICMP6_parameter_problem,
 842                                    ICMP6_parameter_problem_erroneous_header_field,
 843                                    (u8 *) & frag_hdr->fragment_offset_and_more
 844                                    - (u8 *) ip0);
 845       return false;
 846     }
 847   return true;
 848 }
 849
 850 always_inline uword
 851 ip6_reassembly_inline (vlib_main_t * vm,
 852                        vlib_node_runtime_t * node,
 853                        vlib_frame_t * frame, bool is_feature)
 854 {
 855   u32 *from = vlib_frame_vector_args (frame);
 856   u32 n_left_from, n_left_to_next, *to_next, next_index;
 857   ip6_reass_main_t *rm = &ip6_reass_main;
 858   ip6_reass_per_thread_t *rt = &rm->per_thread_data[os_get_thread_index ()];
 859   clib_spinlock_lock (&rt->lock);
 860
 861   n_left_from = frame->n_vectors;
 862   next_index = node->cached_next_index;
 863   static u32 *vec_timeout = NULL;       // indexes of buffers which timed out
 864   static u32 *vec_drop_overlap = NULL;  // indexes of buffers dropped due to overlap
 865   static u32 *vec_drop_compress = NULL; // indexes of buffers dropped due to buffer compression
 866   while (n_left_from > 0 || vec_len (vec_timeout) > 0 ||
 867          vec_len (vec_drop_overlap) > 0 || vec_len (vec_drop_compress) > 0)
 868     {
 869       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 870
 871       while (vec_len (vec_timeout) > 0 && n_left_to_next > 0)
 872         {
 873           u32 bi = vec_pop (vec_timeout);
 874           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 875           b->error = node->errors[IP6_ERROR_REASS_TIMEOUT];
 876           to_next[0] = bi;
 877           to_next += 1;
 878           n_left_to_next -= 1;
 879           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 880                                            n_left_to_next, bi,
 881                                            IP6_REASSEMBLY_NEXT_DROP);
 882           ASSERT (rt->buffers_n > 0);
 883           --rt->buffers_n;
 884         }
 885
 886       while (vec_len (vec_drop_overlap) > 0 && n_left_to_next > 0)
 887         {
 888           u32 bi = vec_pop (vec_drop_overlap);
 889           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 890           b->error = node->errors[IP6_ERROR_REASS_OVERLAPPING_FRAGMENT];
 891           to_next[0] = bi;
 892           to_next += 1;
 893           n_left_to_next -= 1;
 894           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 895                                            n_left_to_next, bi,
 896                                            IP6_REASSEMBLY_NEXT_DROP);
 897           ASSERT (rt->buffers_n > 0);
 898           --rt->buffers_n;
 899         }
 900
 901       while (vec_len (vec_drop_compress) > 0 && n_left_to_next > 0)
 902         {
 903           u32 bi = vec_pop (vec_drop_compress);
 904           vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 905           b->error = node->errors[IP6_ERROR_NONE];
 906           to_next[0] = bi;
 907           to_next += 1;
 908           n_left_to_next -= 1;
 909           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 910                                            n_left_to_next, bi,
 911                                            IP6_REASSEMBLY_NEXT_DROP);
 912           ASSERT (rt->buffers_n > 0);
 913           --rt->buffers_n;
 914         }
 915
 916       while (n_left_from > 0 && n_left_to_next > 0)
 917         {
 918           u32 bi0;
 919           vlib_buffer_t *b0;
 920           u32 next0;
 921           u32 error0 = IP6_ERROR_NONE;
 922           u32 icmp_bi = ~0;
 923
 924           bi0 = from[0];
 925           b0 = vlib_get_buffer (vm, bi0);
 926
 927           ip6_header_t *ip0 = vlib_buffer_get_current (b0);
 928           ip6_frag_hdr_t *frag_hdr = NULL;
 929           ip6_ext_header_t *prev_hdr;
 930           if (ip6_ext_hdr (ip0->protocol))
 931             {
 932               ip6_ext_header_find_t (ip0, prev_hdr, frag_hdr,
 933                                      IP_PROTOCOL_IPV6_FRAGMENTATION);
 934             }
 935           if (!frag_hdr)
 936             {
 937               // this is a regular packet - no fragmentation
 938               next0 = IP6_REASSEMBLY_NEXT_INPUT;
 939               goto skip_reass;
 940             }
 941           if (0 == ip6_frag_hdr_offset (frag_hdr))
 942             {
 943               // first fragment - verify upper-layer is present
 944               if (!ip6_reass_verify_upper_layer_present (node, b0, frag_hdr))
 945                 {
 946                   next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
 947                   goto skip_reass;
 948                 }
 949             }
 950           if (!ip6_reass_verify_fragment_multiple_8 (vm, node, b0, frag_hdr)
 951               || !ip6_reass_verify_packet_size_lt_64k (vm, node, b0,
 952                                                        frag_hdr))
 953             {
 954               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
 955               goto skip_reass;
 956             }
 957           vnet_buffer (b0)->ip.reass.ip6_frag_hdr_offset =
 958             (u8 *) frag_hdr - (u8 *) ip0;
 959
 960           ip6_reass_key_t k;
 961           k.src.as_u64[0] = ip0->src_address.as_u64[0];
 962           k.src.as_u64[1] = ip0->src_address.as_u64[1];
 963           k.dst.as_u64[0] = ip0->dst_address.as_u64[0];
 964           k.dst.as_u64[1] = ip0->dst_address.as_u64[1];
 965           k.xx_id = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 966           k.frag_id = frag_hdr->identification;
 967           k.proto = ip0->protocol;
 968           k.unused = 0;
 969           ip6_reass_t *reass =
 970             ip6_reass_find_or_create (vm, node, rm, rt, &k, &icmp_bi,
 971                                       &vec_timeout);
 972
 973           if (reass)
 974             {
 975               ip6_reass_update (vm, node, rm, rt, reass, &bi0, &next0,
 976                                 &error0, frag_hdr, &vec_drop_overlap,
 977                                 &vec_drop_compress, is_feature);
 978             }
 979           else
 980             {
 981               next0 = IP6_REASSEMBLY_NEXT_DROP;
 982               error0 = IP6_ERROR_REASS_LIMIT_REACHED;
 983             }
 984
 985           b0->error = node->errors[error0];
 986
 987           if (~0 != bi0)
 988             {
 989             skip_reass:
 990               to_next[0] = bi0;
 991               to_next += 1;
 992               n_left_to_next -= 1;
 993               if (is_feature && IP6_ERROR_NONE == error0)
 994                 {
 995                   vnet_feature_next (vnet_buffer (b0)->sw_if_index[VLIB_RX],
 996                                      &next0, b0);
 997                 }
 998               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 999                                                n_left_to_next, bi0, next0);
1000             }
1001
1002           if (~0 != icmp_bi)
1003             {
1004               next0 = IP6_REASSEMBLY_NEXT_ICMP_ERROR;
1005               to_next[0] = icmp_bi;
1006               to_next += 1;
1007               n_left_to_next -= 1;
1008               vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1009                                                n_left_to_next, icmp_bi,
1010                                                next0);
1011             }
1012           from += 1;
1013           n_left_from -= 1;
1014         }
1015
1016       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1017     }
1018
1019   clib_spinlock_unlock (&rt->lock);
1020   return frame->n_vectors;
1021 }
1022
1023 static char *ip6_reassembly_error_strings[] = {
1024 #define _(sym, string) string,
1025   foreach_ip6_error
1026 #undef _
1027 };
1028
1029 always_inline uword
1030 ip6_reassembly (vlib_main_t * vm, vlib_node_runtime_t * node,
1031                 vlib_frame_t * frame)
1032 {
1033   return ip6_reassembly_inline (vm, node, frame, false /* is_feature */ );
1034 }
1035
1036 /* *INDENT-OFF* */
1037 VLIB_REGISTER_NODE (ip6_reass_node, static) = {
1038     .function = ip6_reassembly,
1039     .name = "ip6-reassembly",
1040     .vector_size = sizeof (u32),
1041     .format_trace = format_ip6_reass_trace,
1042     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1043     .error_strings = ip6_reassembly_error_strings,
1044     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1045     .next_nodes =
1046         {
1047                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1048                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1049                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1050         },
1051 };
1052 /* *INDENT-ON* */
1053
1054 VLIB_NODE_FUNCTION_MULTIARCH (ip6_reass_node, ip6_reassembly);
1055
1056 always_inline uword
1057 ip6_reassembly_feature (vlib_main_t * vm,
1058                         vlib_node_runtime_t * node, vlib_frame_t * frame)
1059 {
1060   return ip6_reassembly_inline (vm, node, frame, true /* is_feature */ );
1061 }
1062
1063 /* *INDENT-OFF* */
1064 VLIB_REGISTER_NODE (ip6_reass_node_feature, static) = {
1065     .function = ip6_reassembly_feature,
1066     .name = "ip6-reassembly-feature",
1067     .vector_size = sizeof (u32),
1068     .format_trace = format_ip6_reass_trace,
1069     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1070     .error_strings = ip6_reassembly_error_strings,
1071     .n_next_nodes = IP6_REASSEMBLY_N_NEXT,
1072     .next_nodes =
1073         {
1074                 [IP6_REASSEMBLY_NEXT_INPUT] = "ip6-input",
1075                 [IP6_REASSEMBLY_NEXT_DROP] = "ip6-drop",
1076                 [IP6_REASSEMBLY_NEXT_ICMP_ERROR] = "ip6-icmp-error",
1077         },
1078 };
1079 /* *INDENT-ON* */
1080
1081 VLIB_NODE_FUNCTION_MULTIARCH (ip6_reass_node_feature, ip6_reassembly_feature);
1082
1083 /* *INDENT-OFF* */
1084 VNET_FEATURE_INIT (ip6_reassembly_feature, static) = {
1085     .arc_name = "ip6-unicast",
1086     .node_name = "ip6-reassembly-feature",
1087     .runs_before = VNET_FEATURES ("ip6-lookup"),
1088     .runs_after = 0,
1089 };
1090 /* *INDENT-ON* */
1091
1092 static u32
1093 ip6_reass_get_nbuckets ()
1094 {
1095   ip6_reass_main_t *rm = &ip6_reass_main;
1096   u32 nbuckets;
1097   u8 i;
1098
1099   nbuckets = (u32) (rm->max_reass_n / IP6_REASS_HT_LOAD_FACTOR);
1100
1101   for (i = 0; i < 31; i++)
1102     if ((1 << i) >= nbuckets)
1103       break;
1104   nbuckets = 1 << i;
1105
1106   return nbuckets;
1107 }
1108
1109 typedef enum
1110 {
1111   IP6_EVENT_CONFIG_CHANGED = 1,
1112 } ip6_reass_event_t;
1113
1114 typedef struct
1115 {
1116   int failure;
1117   clib_bihash_48_8_t *new_hash;
1118 } ip6_rehash_cb_ctx;
1119
1120 static void
1121 ip6_rehash_cb (clib_bihash_kv_48_8_t * kv, void *_ctx)
1122 {
1123   ip6_rehash_cb_ctx *ctx = _ctx;
1124   if (clib_bihash_add_del_48_8 (ctx->new_hash, kv, 1))
1125     {
1126       ctx->failure = 1;
1127     }
1128 }
1129
1130 static void
1131 ip6_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1132                       u32 expire_walk_interval_ms)
1133 {
1134   ip6_reass_main.timeout_ms = timeout_ms;
1135   ip6_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1136   ip6_reass_main.max_reass_n = max_reassemblies;
1137   ip6_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1138 }
1139
1140 vnet_api_error_t
1141 ip6_reass_set (u32 timeout_ms, u32 max_reassemblies,
1142                u32 expire_walk_interval_ms)
1143 {
1144   u32 old_nbuckets = ip6_reass_get_nbuckets ();
1145   ip6_reass_set_params (timeout_ms, max_reassemblies,
1146                         expire_walk_interval_ms);
1147   vlib_process_signal_event (ip6_reass_main.vlib_main,
1148                              ip6_reass_main.ip6_reass_expire_node_idx,
1149                              IP6_EVENT_CONFIG_CHANGED, 0);
1150   u32 new_nbuckets = ip6_reass_get_nbuckets ();
1151   if (ip6_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1152     {
1153       clib_bihash_48_8_t new_hash;
1154       memset (&new_hash, 0, sizeof (new_hash));
1155       ip6_rehash_cb_ctx ctx;
1156       ctx.failure = 0;
1157       ctx.new_hash = &new_hash;
1158       clib_bihash_init_48_8 (&new_hash, "ip6-reass", new_nbuckets,
1159                              new_nbuckets * 1024);
1160       clib_bihash_foreach_key_value_pair_48_8 (&ip6_reass_main.hash,
1161                                                ip6_rehash_cb, &ctx);
1162       if (ctx.failure)
1163         {
1164           clib_bihash_free_48_8 (&new_hash);
1165           return -1;
1166         }
1167       else
1168         {
1169           clib_bihash_free_48_8 (&ip6_reass_main.hash);
1170           clib_memcpy (&ip6_reass_main.hash, &new_hash,
1171                        sizeof (ip6_reass_main.hash));
1172         }
1173     }
1174   return 0;
1175 }
1176
1177 vnet_api_error_t
1178 ip6_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1179                u32 * expire_walk_interval_ms)
1180 {
1181   *timeout_ms = ip6_reass_main.timeout_ms;
1182   *max_reassemblies = ip6_reass_main.max_reass_n;
1183   *expire_walk_interval_ms = ip6_reass_main.expire_walk_interval_ms;
1184   return 0;
1185 }
1186
1187 static clib_error_t *
1188 ip6_reass_init_function (vlib_main_t * vm)
1189 {
1190   ip6_reass_main_t *rm = &ip6_reass_main;
1191   clib_error_t *error = 0;
1192   u32 nbuckets;
1193   vlib_node_t *node;
1194
1195   rm->vlib_main = vm;
1196   rm->vnet_main = vnet_get_main ();
1197
1198   vec_validate (rm->per_thread_data, vlib_num_workers () + 1);
1199   ip6_reass_per_thread_t *rt;
1200   vec_foreach (rt, rm->per_thread_data)
1201   {
1202     clib_spinlock_init (&rt->lock);
1203     pool_alloc (rt->pool, rm->max_reass_n);
1204   }
1205
1206   node = vlib_get_node_by_name (vm, (u8 *) "ip6-reassembly-expire-walk");
1207   ASSERT (node);
1208   rm->ip6_reass_expire_node_idx = node->index;
1209
1210   ip6_reass_set_params (IP6_REASS_TIMEOUT_DEFAULT_MS,
1211                         IP6_REASS_MAX_REASSEMBLIES_DEFAULT,
1212                         IP6_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1213
1214   nbuckets = ip6_reass_get_nbuckets ();
1215   clib_bihash_init_48_8 (&rm->hash, "ip6-reass", nbuckets, nbuckets * 1024);
1216
1217   node = vlib_get_node_by_name (vm, (u8 *) "ip6-drop");
1218   ASSERT (node);
1219   rm->ip6_drop_idx = node->index;
1220   node = vlib_get_node_by_name (vm, (u8 *) "ip6-icmp-error");
1221   ASSERT (node);
1222   rm->ip6_icmp_error_idx = node->index;
1223
1224   if ((error = vlib_call_init_function (vm, ip_main_init)))
1225     return error;
1226   ip6_register_protocol (IP_PROTOCOL_IPV6_FRAGMENTATION,
1227                          ip6_reass_node.index);
1228
1229   return error;
1230 }
1231
1232 VLIB_INIT_FUNCTION (ip6_reass_init_function);
1233
1234 static uword
1235 ip6_reass_walk_expired (vlib_main_t * vm,
1236                         vlib_node_runtime_t * node, vlib_frame_t * f)
1237 {
1238   ip6_reass_main_t *rm = &ip6_reass_main;
1239   uword event_type, *event_data = 0;
1240
1241   while (true)
1242     {
1243       vlib_process_wait_for_event_or_clock (vm,
1244                                             (f64) rm->expire_walk_interval_ms
1245                                             / (f64) MSEC_PER_SEC);
1246       event_type = vlib_process_get_events (vm, &event_data);
1247
1248       switch (event_type)
1249         {
1250         case ~0:                /* no events => timeout */
1251           /* nothing to do here */
1252           break;
1253         case IP6_EVENT_CONFIG_CHANGED:
1254           break;
1255         default:
1256           clib_warning ("BUG: event type 0x%wx", event_type);
1257           break;
1258         }
1259       f64 now = vlib_time_now (vm);
1260
1261       ip6_reass_t *reass;
1262       u32 *vec_timeout = NULL;
1263       int *pool_indexes_to_free = NULL;
1264
1265       uword thread_index = 0;
1266       int index;
1267       const uword nthreads = os_get_nthreads ();
1268       u32 *vec_icmp_bi = NULL;
1269       for (thread_index = 0; thread_index < nthreads; ++thread_index)
1270         {
1271           ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1272           clib_spinlock_lock (&rt->lock);
1273
1274           vec_reset_length (pool_indexes_to_free);
1275           /* *INDENT-OFF* */
1276           pool_foreach_index (index, rt->pool, ({
1277                                 reass = pool_elt_at_index (rt->pool, index);
1278                                 if (now > reass->last_heard + rm->timeout)
1279                                   {
1280                                     vec_add1 (pool_indexes_to_free, index);
1281                                   }
1282                               }));
1283           /* *INDENT-ON* */
1284           int *i;
1285           /* *INDENT-OFF* */
1286           vec_foreach (i, pool_indexes_to_free)
1287           {
1288             ip6_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1289             u32 icmp_bi = ~0;
1290             u32 before = vec_len (vec_timeout);
1291             vlib_buffer_t *b = vlib_get_buffer (vm, reass->first_bi);
1292             if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1293               {
1294                 if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1295                                         b->trace_index))
1296                   {
1297                     /* the trace is gone, don't trace this buffer anymore */
1298                     b->flags &= ~VLIB_BUFFER_IS_TRACED;
1299                   }
1300               }
1301             ip6_reass_on_timeout (vm, node, rm, reass, &icmp_bi, &vec_timeout);
1302             u32 after = vec_len (vec_timeout);
1303             ASSERT (rt->buffers_n >= (after - before));
1304             rt->buffers_n -= (after - before);
1305             if (~0 != icmp_bi)
1306               {
1307                 vec_add1 (vec_icmp_bi, icmp_bi);
1308                 ASSERT (rt->buffers_n > 0);
1309                 --rt->buffers_n;
1310               }
1311             ip6_reass_free (rm, rt, reass);
1312           }
1313           /* *INDENT-ON* */
1314
1315           clib_spinlock_unlock (&rt->lock);
1316         }
1317
1318       while (vec_len (vec_timeout) > 0)
1319         {
1320           vlib_frame_t *f = vlib_get_frame_to_node (vm, rm->ip6_drop_idx);
1321           u32 *to_next = vlib_frame_vector_args (f);
1322           u32 n_left_to_next = VLIB_FRAME_SIZE - f->n_vectors;
1323           int trace_frame = 0;
1324           while (vec_len (vec_timeout) > 0 && n_left_to_next > 0)
1325             {
1326               u32 bi = vec_pop (vec_timeout);
1327               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1328               if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1329                 {
1330                   if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1331                                           b->trace_index))
1332                     {
1333                       /* the trace is gone, don't trace this buffer anymore */
1334                       b->flags &= ~VLIB_BUFFER_IS_TRACED;
1335                     }
1336                   else
1337                     {
1338                       trace_frame = 1;
1339                     }
1340                 }
1341               b->error = node->errors[IP6_ERROR_REASS_TIMEOUT];
1342               to_next[0] = bi;
1343               ++f->n_vectors;
1344               to_next += 1;
1345               n_left_to_next -= 1;
1346             }
1347           f->flags |= (trace_frame * VLIB_FRAME_TRACE);
1348           vlib_put_frame_to_node (vm, rm->ip6_drop_idx, f);
1349         }
1350
1351       while (vec_len (vec_icmp_bi) > 0)
1352         {
1353           vlib_frame_t *f =
1354             vlib_get_frame_to_node (vm, rm->ip6_icmp_error_idx);
1355           u32 *to_next = vlib_frame_vector_args (f);
1356           u32 n_left_to_next = VLIB_FRAME_SIZE - f->n_vectors;
1357           int trace_frame = 0;
1358           while (vec_len (vec_icmp_bi) > 0 && n_left_to_next > 0)
1359             {
1360               u32 bi = vec_pop (vec_icmp_bi);
1361               vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1362               if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
1363                 {
1364                   if (pool_is_free_index (vm->trace_main.trace_buffer_pool,
1365                                           b->trace_index))
1366                     {
1367                       /* the trace is gone, don't trace this buffer anymore */
1368                       b->flags &= ~VLIB_BUFFER_IS_TRACED;
1369                     }
1370                   else
1371                     {
1372                       trace_frame = 1;
1373                     }
1374                 }
1375               b->error = node->errors[IP6_ERROR_REASS_TIMEOUT];
1376               to_next[0] = bi;
1377               ++f->n_vectors;
1378               to_next += 1;
1379               n_left_to_next -= 1;
1380             }
1381           f->flags |= (trace_frame * VLIB_FRAME_TRACE);
1382           vlib_put_frame_to_node (vm, rm->ip6_icmp_error_idx, f);
1383         }
1384
1385       vec_free (pool_indexes_to_free);
1386       vec_free (vec_timeout);
1387       vec_free (vec_icmp_bi);
1388       if (event_data)
1389         {
1390           _vec_len (event_data) = 0;
1391         }
1392     }
1393
1394   return 0;
1395 }
1396
1397 static vlib_node_registration_t ip6_reass_expire_node;
1398
1399 /* *INDENT-OFF* */
1400 VLIB_REGISTER_NODE (ip6_reass_expire_node, static) = {
1401     .function = ip6_reass_walk_expired,
1402     .format_trace = format_ip6_reass_trace,
1403     .type = VLIB_NODE_TYPE_PROCESS,
1404     .name = "ip6-reassembly-expire-walk",
1405
1406     .n_errors = ARRAY_LEN (ip6_reassembly_error_strings),
1407     .error_strings = ip6_reassembly_error_strings,
1408
1409 };
1410 /* *INDENT-ON* */
1411
1412 static u8 *
1413 format_ip6_reass_key (u8 * s, va_list * args)
1414 {
1415   ip6_reass_key_t *key = va_arg (*args, ip6_reass_key_t *);
1416   s = format (s, "xx_id: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1417               key->xx_id, format_ip6_address, &key->src, format_ip6_address,
1418               &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1419   return s;
1420 }
1421
1422 static u8 *
1423 format_ip6_reass (u8 * s, va_list * args)
1424 {
1425   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1426   ip6_reass_t *reass = va_arg (*args, ip6_reass_t *);
1427
1428   s = format (s, "ID: %lu, key: %U\n  first_bi: %u, data_len: %u, "
1429               "last_packet_octet: %u, trace_op_counter: %u\n",
1430               reass->id, format_ip6_reass_key, &reass->key, reass->first_bi,
1431               reass->data_len, reass->last_packet_octet,
1432               reass->trace_op_counter);
1433   u32 bi = reass->first_bi;
1434   u32 counter = 0;
1435   while (~0 != bi)
1436     {
1437       vlib_buffer_t *b = vlib_get_buffer (vm, bi);
1438       vnet_buffer_opaque_t *vnb = vnet_buffer (b);
1439       s = format (s, "  #%03u: range: [%u, %u], bi: %u, off: %d, len: %u, "
1440                   "fragment[%u, %u]\n",
1441                   counter, vnb->ip.reass.range_first,
1442                   vnb->ip.reass.range_last, bi,
1443                   ip6_reass_buffer_get_data_offset_no_check (b),
1444                   ip6_reass_buffer_get_data_len_no_check (b),
1445                   vnb->ip.reass.fragment_first, vnb->ip.reass.fragment_last);
1446       if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1447         {
1448           bi = b->next_buffer;
1449         }
1450       else
1451         {
1452           bi = ~0;
1453         }
1454     }
1455   return s;
1456 }
1457
1458 static clib_error_t *
1459 show_ip6_reass (vlib_main_t * vm, unformat_input_t * input,
1460                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1461 {
1462   ip6_reass_main_t *rm = &ip6_reass_main;
1463
1464   vlib_cli_output (vm, "---------------------");
1465   vlib_cli_output (vm, "IP6 reassembly status");
1466   vlib_cli_output (vm, "---------------------");
1467   bool details = false;
1468   if (unformat (input, "details"))
1469     {
1470       details = true;
1471     }
1472
1473   u32 sum_reass_n = 0;
1474   u64 sum_buffers_n = 0;
1475   ip6_reass_t *reass;
1476   uword thread_index;
1477   const uword nthreads = os_get_nthreads ();
1478   for (thread_index = 0; thread_index < nthreads; ++thread_index)
1479     {
1480       ip6_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1481       clib_spinlock_lock (&rt->lock);
1482       if (details)
1483         {
1484           /* *INDENT-OFF* */
1485           pool_foreach (reass, rt->pool, {
1486             vlib_cli_output (vm, "%U", format_ip6_reass, vm, reass);
1487           });
1488           /* *INDENT-ON* */
1489         }
1490       sum_reass_n += rt->reass_n;
1491       sum_buffers_n += rt->buffers_n;
1492       clib_spinlock_unlock (&rt->lock);
1493     }
1494   vlib_cli_output (vm, "---------------------");
1495   vlib_cli_output (vm, "Current IP6 reassemblies count: %lu\n",
1496                    (long unsigned) sum_reass_n);
1497   vlib_cli_output (vm, "Maximum configured concurrent IP6 reassemblies per "
1498                    "worker-thread: %lu\n", (long unsigned) rm->max_reass_n);
1499   vlib_cli_output (vm, "Buffers in use: %lu\n",
1500                    (long unsigned) sum_buffers_n);
1501   return 0;
1502 }
1503
1504 /* *INDENT-OFF* */
1505 VLIB_CLI_COMMAND (show_ip6_reassembly_cmd, static) = {
1506     .path = "show ip6-reassembly",
1507     .short_help = "show ip6-reassembly [details]",
1508     .function = show_ip6_reass,
1509 };
1510 /* *INDENT-ON* */
1511
1512 vnet_api_error_t
1513 ip6_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1514 {
1515   return vnet_feature_enable_disable ("ip6-unicast", "ip6-reassembly-feature",
1516                                       sw_if_index, enable_disable, 0, 0);
1517 }
1518
1519 /*
1520  * fd.io coding-style-patch-verification: ON
1521  *
1522  * Local Variables:
1523  * eval: (c-set-style "gnu")
1524  * End:
1525  */