src/vnet/ip/reass/ip4_sv_reass.c

   1 /*
   2  * Copyright (c) 2017 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 /**
  17  * @file
  18  * @brief IPv4 Shallow Virtual Reassembly.
  19  *
  20  * This file contains the source code for IPv4 Shallow Virtual reassembly.
  21  */
  22
  23 #include <vppinfra/vec.h>
  24 #include <vnet/vnet.h>
  25 #include <vnet/ip/ip.h>
  26 #include <vnet/ip/ip4_to_ip6.h>
  27 #include <vppinfra/fifo.h>
  28 #include <vppinfra/bihash_16_8.h>
  29 #include <vnet/ip/reass/ip4_sv_reass.h>
  30
  31 #define MSEC_PER_SEC 1000
  32 #define IP4_SV_REASS_TIMEOUT_DEFAULT_MS 100
  33 #define IP4_SV_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS 10000      // 10 seconds default
  34 #define IP4_SV_REASS_MAX_REASSEMBLIES_DEFAULT 1024
  35 #define IP4_SV_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT 3
  36 #define IP4_SV_REASS_HT_LOAD_FACTOR (0.75)
  37
  38 typedef enum
  39 {
  40   IP4_SV_REASS_RC_OK,
  41   IP4_SV_REASS_RC_TOO_MANY_FRAGMENTS,
  42   IP4_SV_REASS_RC_UNSUPP_IP_PROTO,
  43 } ip4_sv_reass_rc_t;
  44
  45 typedef struct
  46 {
  47   union
  48   {
  49     struct
  50     {
  51       u32 fib_index;
  52       ip4_address_t src;
  53       ip4_address_t dst;
  54       u16 frag_id;
  55       u8 proto;
  56       u8 unused;
  57     };
  58     u64 as_u64[2];
  59   };
  60 } ip4_sv_reass_key_t;
  61
  62 typedef union
  63 {
  64   struct
  65   {
  66     u32 reass_index;
  67     u32 thread_index;
  68   };
  69   u64 as_u64;
  70 } ip4_sv_reass_val_t;
  71
  72 typedef union
  73 {
  74   struct
  75   {
  76     ip4_sv_reass_key_t k;
  77     ip4_sv_reass_val_t v;
  78   };
  79   clib_bihash_kv_16_8_t kv;
  80 } ip4_sv_reass_kv_t;
  81
  82 typedef struct
  83 {
  84   // hash table key
  85   ip4_sv_reass_key_t key;
  86   // time when last packet was received
  87   f64 last_heard;
  88   // internal id of this reassembly
  89   u64 id;
  90   // trace operation counter
  91   u32 trace_op_counter;
  92   // minimum fragment length for this reassembly - used to estimate MTU
  93   u16 min_fragment_length;
  94   // buffer indexes of buffers in this reassembly in chronological order -
  95   // including overlaps and duplicate fragments
  96   u32 *cached_buffers;
  97   // set to true when this reassembly is completed
  98   bool is_complete;
  99   // ip protocol
 100   u8 ip_proto;
 101   u8 icmp_type_or_tcp_flags;
 102   u32 tcp_ack_number;
 103   u32 tcp_seq_number;
 104   // l4 src port
 105   u16 l4_src_port;
 106   // l4 dst port
 107   u16 l4_dst_port;
 108   u32 next_index;
 109   // lru indexes
 110   u32 lru_prev;
 111   u32 lru_next;
 112 } ip4_sv_reass_t;
 113
 114 typedef struct
 115 {
 116   ip4_sv_reass_t *pool;
 117   u32 reass_n;
 118   u32 id_counter;
 119   clib_spinlock_t lock;
 120   // lru indexes
 121   u32 lru_first;
 122   u32 lru_last;
 123
 124 } ip4_sv_reass_per_thread_t;
 125
 126 typedef struct
 127 {
 128   // IPv4 config
 129   u32 timeout_ms;
 130   f64 timeout;
 131   u32 expire_walk_interval_ms;
 132   // maximum number of fragments in one reassembly
 133   u32 max_reass_len;
 134   // maximum number of reassemblies
 135   u32 max_reass_n;
 136
 137   // IPv4 runtime
 138   clib_bihash_16_8_t hash;
 139   // per-thread data
 140   ip4_sv_reass_per_thread_t *per_thread_data;
 141
 142   // convenience
 143   vlib_main_t *vlib_main;
 144   vnet_main_t *vnet_main;
 145
 146   // node index of ip4-drop node
 147   u32 ip4_drop_idx;
 148   u32 ip4_sv_reass_expire_node_idx;
 149
 150   /** Worker handoff */
 151   u32 fq_index;
 152   u32 fq_feature_index;
 153
 154   // reference count for enabling/disabling feature - per interface
 155   u32 *feature_use_refcount_per_intf;
 156
 157   // reference count for enabling/disabling feature - per interface
 158   u32 *output_feature_use_refcount_per_intf;
 159
 160 } ip4_sv_reass_main_t;
 161
 162 extern ip4_sv_reass_main_t ip4_sv_reass_main;
 163
 164 #ifndef CLIB_MARCH_VARIANT
 165 ip4_sv_reass_main_t ip4_sv_reass_main;
 166 #endif /* CLIB_MARCH_VARIANT */
 167
 168 typedef enum
 169 {
 170   IP4_SV_REASSEMBLY_NEXT_INPUT,
 171   IP4_SV_REASSEMBLY_NEXT_DROP,
 172   IP4_SV_REASSEMBLY_NEXT_HANDOFF,
 173   IP4_SV_REASSEMBLY_N_NEXT,
 174 } ip4_sv_reass_next_t;
 175
 176 typedef enum
 177 {
 178   REASS_FRAGMENT_CACHE,
 179   REASS_FINISH,
 180   REASS_FRAGMENT_FORWARD,
 181   REASS_PASSTHROUGH,
 182 } ip4_sv_reass_trace_operation_e;
 183
 184 typedef struct
 185 {
 186   ip4_sv_reass_trace_operation_e action;
 187   u32 reass_id;
 188   u32 op_id;
 189   u8 ip_proto;
 190   u16 l4_src_port;
 191   u16 l4_dst_port;
 192   int l4_layer_truncated;
 193 } ip4_sv_reass_trace_t;
 194
 195 extern vlib_node_registration_t ip4_sv_reass_node;
 196 extern vlib_node_registration_t ip4_sv_reass_node_feature;
 197
 198 static u8 *
 199 format_ip4_sv_reass_trace (u8 * s, va_list * args)
 200 {
 201   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
 202   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
 203   ip4_sv_reass_trace_t *t = va_arg (*args, ip4_sv_reass_trace_t *);
 204   if (REASS_PASSTHROUGH != t->action)
 205     {
 206       s = format (s, "reass id: %u, op id: %u ", t->reass_id, t->op_id);
 207     }
 208   switch (t->action)
 209     {
 210     case REASS_FRAGMENT_CACHE:
 211       s = format (s, "[cached]");
 212       break;
 213     case REASS_FINISH:
 214       s =
 215         format (s, "[finish, ip proto=%u, src_port=%u, dst_port=%u]",
 216                 t->ip_proto, clib_net_to_host_u16 (t->l4_src_port),
 217                 clib_net_to_host_u16 (t->l4_dst_port));
 218       break;
 219     case REASS_FRAGMENT_FORWARD:
 220       s =
 221         format (s, "[forward, ip proto=%u, src_port=%u, dst_port=%u]",
 222                 t->ip_proto, clib_net_to_host_u16 (t->l4_src_port),
 223                 clib_net_to_host_u16 (t->l4_dst_port));
 224       break;
 225     case REASS_PASSTHROUGH:
 226       s = format (s, "[not-fragmented]");
 227       break;
 228     }
 229   if (t->l4_layer_truncated)
 230     {
 231       s = format (s, " [l4-layer-truncated]");
 232     }
 233   return s;
 234 }
 235
 236 static void
 237 ip4_sv_reass_add_trace (vlib_main_t *vm, vlib_node_runtime_t *node,
 238                         ip4_sv_reass_t *reass, u32 bi,
 239                         ip4_sv_reass_trace_operation_e action, u32 ip_proto,
 240                         u16 l4_src_port, u16 l4_dst_port,
 241                         int l4_layer_truncated)
 242 {
 243   vlib_buffer_t *b = vlib_get_buffer (vm, bi);
 244   if (pool_is_free_index
 245       (vm->trace_main.trace_buffer_pool, vlib_buffer_get_trace_index (b)))
 246     {
 247       // this buffer's trace is gone
 248       b->flags &= ~VLIB_BUFFER_IS_TRACED;
 249       return;
 250     }
 251   ip4_sv_reass_trace_t *t = vlib_add_trace (vm, node, b, sizeof (t[0]));
 252   if (reass)
 253     {
 254       t->reass_id = reass->id;
 255       t->op_id = reass->trace_op_counter;
 256       ++reass->trace_op_counter;
 257     }
 258   t->action = action;
 259   t->ip_proto = ip_proto;
 260   t->l4_src_port = l4_src_port;
 261   t->l4_dst_port = l4_dst_port;
 262   t->l4_layer_truncated = l4_layer_truncated;
 263 #if 0
 264   static u8 *s = NULL;
 265   s = format (s, "%U", format_ip4_sv_reass_trace, NULL, NULL, t);
 266   printf ("%.*s\n", vec_len (s), s);
 267   fflush (stdout);
 268   vec_reset_length (s);
 269 #endif
 270 }
 271
 272
 273 always_inline void
 274 ip4_sv_reass_free (vlib_main_t * vm, ip4_sv_reass_main_t * rm,
 275                    ip4_sv_reass_per_thread_t * rt, ip4_sv_reass_t * reass)
 276 {
 277   clib_bihash_kv_16_8_t kv;
 278   kv.key[0] = reass->key.as_u64[0];
 279   kv.key[1] = reass->key.as_u64[1];
 280   clib_bihash_add_del_16_8 (&rm->hash, &kv, 0);
 281   vlib_buffer_free (vm, reass->cached_buffers,
 282                     vec_len (reass->cached_buffers));
 283   vec_free (reass->cached_buffers);
 284   reass->cached_buffers = NULL;
 285   if (~0 != reass->lru_prev)
 286     {
 287       ip4_sv_reass_t *lru_prev =
 288         pool_elt_at_index (rt->pool, reass->lru_prev);
 289       lru_prev->lru_next = reass->lru_next;
 290     }
 291   if (~0 != reass->lru_next)
 292     {
 293       ip4_sv_reass_t *lru_next =
 294         pool_elt_at_index (rt->pool, reass->lru_next);
 295       lru_next->lru_prev = reass->lru_prev;
 296     }
 297   if (rt->lru_first == reass - rt->pool)
 298     {
 299       rt->lru_first = reass->lru_next;
 300     }
 301   if (rt->lru_last == reass - rt->pool)
 302     {
 303       rt->lru_last = reass->lru_prev;
 304     }
 305   pool_put (rt->pool, reass);
 306   --rt->reass_n;
 307 }
 308
 309 always_inline void
 310 ip4_sv_reass_init (ip4_sv_reass_t * reass)
 311 {
 312   reass->cached_buffers = NULL;
 313   reass->is_complete = false;
 314 }
 315
 316 always_inline ip4_sv_reass_t *
 317 ip4_sv_reass_find_or_create (vlib_main_t * vm, ip4_sv_reass_main_t * rm,
 318                              ip4_sv_reass_per_thread_t * rt,
 319                              ip4_sv_reass_kv_t * kv, u8 * do_handoff)
 320 {
 321   ip4_sv_reass_t *reass = NULL;
 322   f64 now = vlib_time_now (vm);
 323
 324 again:
 325
 326   if (!clib_bihash_search_16_8 (&rm->hash, &kv->kv, &kv->kv))
 327     {
 328       if (vm->thread_index != kv->v.thread_index)
 329         {
 330           *do_handoff = 1;
 331           return NULL;
 332         }
 333       reass = pool_elt_at_index (rt->pool, kv->v.reass_index);
 334
 335       if (now > reass->last_heard + rm->timeout)
 336         {
 337           ip4_sv_reass_free (vm, rm, rt, reass);
 338           reass = NULL;
 339         }
 340     }
 341
 342   if (reass)
 343     {
 344       reass->last_heard = now;
 345       return reass;
 346     }
 347
 348   if (rt->reass_n >= rm->max_reass_n && rm->max_reass_n)
 349     {
 350       reass = pool_elt_at_index (rt->pool, rt->lru_first);
 351       ip4_sv_reass_free (vm, rm, rt, reass);
 352     }
 353
 354   pool_get (rt->pool, reass);
 355   clib_memset (reass, 0, sizeof (*reass));
 356   reass->id = ((u64) vm->thread_index * 1000000000) + rt->id_counter;
 357   ++rt->id_counter;
 358   ip4_sv_reass_init (reass);
 359   ++rt->reass_n;
 360   reass->lru_prev = reass->lru_next = ~0;
 361
 362   if (~0 != rt->lru_last)
 363     {
 364       ip4_sv_reass_t *lru_last = pool_elt_at_index (rt->pool, rt->lru_last);
 365       reass->lru_prev = rt->lru_last;
 366       lru_last->lru_next = rt->lru_last = reass - rt->pool;
 367     }
 368
 369   if (~0 == rt->lru_first)
 370     {
 371       rt->lru_first = rt->lru_last = reass - rt->pool;
 372     }
 373
 374   reass->key.as_u64[0] = kv->kv.key[0];
 375   reass->key.as_u64[1] = kv->kv.key[1];
 376   kv->v.reass_index = (reass - rt->pool);
 377   kv->v.thread_index = vm->thread_index;
 378   reass->last_heard = now;
 379
 380   int rv = clib_bihash_add_del_16_8 (&rm->hash, &kv->kv, 2);
 381   if (rv)
 382     {
 383       ip4_sv_reass_free (vm, rm, rt, reass);
 384       reass = NULL;
 385       // if other worker created a context already work with the other copy
 386       if (-2 == rv)
 387         goto again;
 388     }
 389
 390   return reass;
 391 }
 392
 393 always_inline ip4_sv_reass_rc_t
 394 ip4_sv_reass_update (vlib_main_t *vm, vlib_node_runtime_t *node,
 395                      ip4_sv_reass_main_t *rm, ip4_header_t *ip0,
 396                      ip4_sv_reass_t *reass, u32 bi0)
 397 {
 398   vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
 399   ip4_sv_reass_rc_t rc = IP4_SV_REASS_RC_OK;
 400   const u32 fragment_first = ip4_get_fragment_offset_bytes (ip0);
 401   if (0 == fragment_first)
 402     {
 403       reass->ip_proto = ip0->protocol;
 404       reass->l4_src_port = ip4_get_port (ip0, 1);
 405       reass->l4_dst_port = ip4_get_port (ip0, 0);
 406       if (!reass->l4_src_port || !reass->l4_dst_port)
 407         return IP4_SV_REASS_RC_UNSUPP_IP_PROTO;
 408       if (IP_PROTOCOL_TCP == reass->ip_proto)
 409         {
 410           reass->icmp_type_or_tcp_flags = ((tcp_header_t *) (ip0 + 1))->flags;
 411           reass->tcp_ack_number = ((tcp_header_t *) (ip0 + 1))->ack_number;
 412           reass->tcp_seq_number = ((tcp_header_t *) (ip0 + 1))->seq_number;
 413         }
 414       else if (IP_PROTOCOL_ICMP == reass->ip_proto)
 415         {
 416           reass->icmp_type_or_tcp_flags =
 417             ((icmp46_header_t *) (ip0 + 1))->type;
 418         }
 419       reass->is_complete = true;
 420       vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
 421       if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 422         {
 423           ip4_sv_reass_add_trace (
 424             vm, node, reass, bi0, REASS_FINISH, reass->ip_proto,
 425             reass->l4_src_port, reass->l4_dst_port,
 426             vnet_buffer (b0)->ip.reass.l4_layer_truncated);
 427         }
 428     }
 429   vec_add1 (reass->cached_buffers, bi0);
 430   if (!reass->is_complete)
 431     {
 432       if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 433         {
 434           ip4_sv_reass_add_trace (
 435             vm, node, reass, bi0, REASS_FRAGMENT_CACHE, ~0, ~0, ~0,
 436             vnet_buffer (b0)->ip.reass.l4_layer_truncated);
 437         }
 438       if (vec_len (reass->cached_buffers) > rm->max_reass_len)
 439         {
 440           rc = IP4_SV_REASS_RC_TOO_MANY_FRAGMENTS;
 441         }
 442     }
 443   return rc;
 444 }
 445
 446 always_inline int
 447 l4_layer_truncated (ip4_header_t *ip)
 448 {
 449   static const int l4_layer_length[256] = {
 450     [IP_PROTOCOL_TCP] = sizeof (tcp_header_t),
 451     [IP_PROTOCOL_UDP] = sizeof (udp_header_t),
 452     [IP_PROTOCOL_ICMP] = sizeof (icmp46_header_t),
 453   };
 454
 455   return ((u8 *) ip + ip4_header_bytes (ip) + l4_layer_length[ip->protocol] >
 456           (u8 *) ip + clib_net_to_host_u16 (ip->length));
 457 }
 458
 459 always_inline uword
 460 ip4_sv_reass_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 461                      vlib_frame_t * frame, bool is_feature,
 462                      bool is_output_feature, bool is_custom)
 463 {
 464   u32 *from = vlib_frame_vector_args (frame);
 465   u32 n_left_from, n_left_to_next, *to_next, next_index;
 466   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
 467   ip4_sv_reass_per_thread_t *rt = &rm->per_thread_data[vm->thread_index];
 468   clib_spinlock_lock (&rt->lock);
 469
 470   n_left_from = frame->n_vectors;
 471   next_index = node->cached_next_index;
 472
 473   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
 474   vlib_get_buffers (vm, from, bufs, n_left_from);
 475   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
 476   b = bufs;
 477
 478   /* optimistic case first - no fragments */
 479   while (n_left_from >= 2)
 480     {
 481       vlib_buffer_t *b0, *b1;
 482       u32 next0, next1;
 483       b0 = *b;
 484       b++;
 485       b1 = *b;
 486       b++;
 487
 488       /* Prefetch next iteration. */
 489       if (PREDICT_TRUE (n_left_from >= 4))
 490         {
 491           vlib_buffer_t *p2, *p3;
 492
 493           p2 = *b;
 494           p3 = *(b + 1);
 495
 496           vlib_prefetch_buffer_header (p2, LOAD);
 497           vlib_prefetch_buffer_header (p3, LOAD);
 498
 499           clib_prefetch_load (p2->data);
 500           clib_prefetch_load (p3->data);
 501         }
 502
 503       ip4_header_t *ip0 =
 504         (ip4_header_t *) u8_ptr_add (vlib_buffer_get_current (b0),
 505                                      (is_output_feature ? 1 : 0) *
 506                                      vnet_buffer (b0)->
 507                                      ip.save_rewrite_length);
 508       ip4_header_t *ip1 =
 509         (ip4_header_t *) u8_ptr_add (vlib_buffer_get_current (b1),
 510                                      (is_output_feature ? 1 : 0) *
 511                                      vnet_buffer (b1)->
 512                                      ip.save_rewrite_length);
 513
 514       if (PREDICT_FALSE
 515           (ip4_get_fragment_more (ip0) || ip4_get_fragment_offset (ip0))
 516           || (ip4_get_fragment_more (ip1) || ip4_get_fragment_offset (ip1)))
 517         {
 518           // fragment found, go slow path
 519           b -= 2;
 520           if (b - bufs > 0)
 521             {
 522               vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
 523                                            b - bufs);
 524             }
 525           goto slow_path;
 526         }
 527       if (is_feature)
 528         {
 529           vnet_feature_next (&next0, b0);
 530         }
 531       else
 532         {
 533           next0 = is_custom ? vnet_buffer (b0)->ip.reass.next_index :
 534             IP4_SV_REASSEMBLY_NEXT_INPUT;
 535         }
 536       vnet_buffer (b0)->ip.reass.is_non_first_fragment = 0;
 537       vnet_buffer (b0)->ip.reass.ip_proto = ip0->protocol;
 538       if (l4_layer_truncated (ip0))
 539         {
 540           vnet_buffer (b0)->ip.reass.l4_layer_truncated = 1;
 541           vnet_buffer (b0)->ip.reass.l4_src_port = 0;
 542           vnet_buffer (b0)->ip.reass.l4_dst_port = 0;
 543         }
 544       else
 545         {
 546           vnet_buffer (b0)->ip.reass.l4_layer_truncated = 0;
 547           if (IP_PROTOCOL_TCP == ip0->protocol)
 548             {
 549               vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 550                 ((tcp_header_t *) (ip0 + 1))->flags;
 551               vnet_buffer (b0)->ip.reass.tcp_ack_number =
 552                 ((tcp_header_t *) (ip0 + 1))->ack_number;
 553               vnet_buffer (b0)->ip.reass.tcp_seq_number =
 554                 ((tcp_header_t *) (ip0 + 1))->seq_number;
 555             }
 556           else if (IP_PROTOCOL_ICMP == ip0->protocol)
 557             {
 558               vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 559                 ((icmp46_header_t *) (ip0 + 1))->type;
 560             }
 561           vnet_buffer (b0)->ip.reass.l4_src_port = ip4_get_port (ip0, 1);
 562           vnet_buffer (b0)->ip.reass.l4_dst_port = ip4_get_port (ip0, 0);
 563         }
 564       if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 565         {
 566           ip4_sv_reass_add_trace (
 567             vm, node, NULL, from[(b - 2) - bufs], REASS_PASSTHROUGH,
 568             vnet_buffer (b0)->ip.reass.ip_proto,
 569             vnet_buffer (b0)->ip.reass.l4_src_port,
 570             vnet_buffer (b0)->ip.reass.l4_dst_port,
 571             vnet_buffer (b0)->ip.reass.l4_layer_truncated);
 572         }
 573       if (is_feature)
 574         {
 575           vnet_feature_next (&next1, b1);
 576         }
 577       else
 578         {
 579           next1 = is_custom ? vnet_buffer (b1)->ip.reass.next_index :
 580             IP4_SV_REASSEMBLY_NEXT_INPUT;
 581         }
 582       vnet_buffer (b1)->ip.reass.is_non_first_fragment = 0;
 583       vnet_buffer (b1)->ip.reass.ip_proto = ip1->protocol;
 584       if (l4_layer_truncated (ip1))
 585         {
 586           vnet_buffer (b1)->ip.reass.l4_layer_truncated = 1;
 587           vnet_buffer (b1)->ip.reass.l4_src_port = 0;
 588           vnet_buffer (b1)->ip.reass.l4_dst_port = 0;
 589         }
 590       else
 591         {
 592           vnet_buffer (b1)->ip.reass.l4_layer_truncated = 0;
 593           if (IP_PROTOCOL_TCP == ip1->protocol)
 594             {
 595               vnet_buffer (b1)->ip.reass.icmp_type_or_tcp_flags =
 596                 ((tcp_header_t *) (ip1 + 1))->flags;
 597               vnet_buffer (b1)->ip.reass.tcp_ack_number =
 598                 ((tcp_header_t *) (ip1 + 1))->ack_number;
 599               vnet_buffer (b1)->ip.reass.tcp_seq_number =
 600                 ((tcp_header_t *) (ip1 + 1))->seq_number;
 601             }
 602           else if (IP_PROTOCOL_ICMP == ip1->protocol)
 603             {
 604               vnet_buffer (b1)->ip.reass.icmp_type_or_tcp_flags =
 605                 ((icmp46_header_t *) (ip1 + 1))->type;
 606             }
 607           vnet_buffer (b1)->ip.reass.l4_src_port = ip4_get_port (ip1, 1);
 608           vnet_buffer (b1)->ip.reass.l4_dst_port = ip4_get_port (ip1, 0);
 609         }
 610       if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
 611         {
 612           ip4_sv_reass_add_trace (
 613             vm, node, NULL, from[(b - 1) - bufs], REASS_PASSTHROUGH,
 614             vnet_buffer (b1)->ip.reass.ip_proto,
 615             vnet_buffer (b1)->ip.reass.l4_src_port,
 616             vnet_buffer (b1)->ip.reass.l4_dst_port,
 617             vnet_buffer (b1)->ip.reass.l4_layer_truncated);
 618         }
 619
 620       n_left_from -= 2;
 621       next[0] = next0;
 622       next[1] = next1;
 623       next += 2;
 624     }
 625
 626   while (n_left_from > 0)
 627     {
 628       vlib_buffer_t *b0;
 629       u32 next0;
 630       b0 = *b;
 631       b++;
 632
 633       ip4_header_t *ip0 =
 634         (ip4_header_t *) u8_ptr_add (vlib_buffer_get_current (b0),
 635                                      (is_output_feature ? 1 : 0) *
 636                                      vnet_buffer (b0)->
 637                                      ip.save_rewrite_length);
 638       if (PREDICT_FALSE
 639           (ip4_get_fragment_more (ip0) || ip4_get_fragment_offset (ip0)))
 640         {
 641           // fragment found, go slow path
 642           b -= 1;
 643           if (b - bufs > 0)
 644             {
 645               vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
 646                                            b - bufs);
 647             }
 648           goto slow_path;
 649         }
 650       if (is_feature)
 651         {
 652           vnet_feature_next (&next0, b0);
 653         }
 654       else
 655         {
 656           next0 =
 657             is_custom ? vnet_buffer (b0)->ip.
 658             reass.next_index : IP4_SV_REASSEMBLY_NEXT_INPUT;
 659         }
 660       vnet_buffer (b0)->ip.reass.is_non_first_fragment = 0;
 661       vnet_buffer (b0)->ip.reass.ip_proto = ip0->protocol;
 662       if (l4_layer_truncated (ip0))
 663         {
 664           vnet_buffer (b0)->ip.reass.l4_layer_truncated = 1;
 665         }
 666       else
 667         {
 668           vnet_buffer (b0)->ip.reass.l4_layer_truncated = 0;
 669           if (IP_PROTOCOL_TCP == ip0->protocol)
 670             {
 671               vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 672                 ((tcp_header_t *) (ip0 + 1))->flags;
 673               vnet_buffer (b0)->ip.reass.tcp_ack_number =
 674                 ((tcp_header_t *) (ip0 + 1))->ack_number;
 675               vnet_buffer (b0)->ip.reass.tcp_seq_number =
 676                 ((tcp_header_t *) (ip0 + 1))->seq_number;
 677             }
 678           else if (IP_PROTOCOL_ICMP == ip0->protocol)
 679             {
 680               vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 681                 ((icmp46_header_t *) (ip0 + 1))->type;
 682             }
 683           vnet_buffer (b0)->ip.reass.l4_src_port = ip4_get_port (ip0, 1);
 684           vnet_buffer (b0)->ip.reass.l4_dst_port = ip4_get_port (ip0, 0);
 685         }
 686       if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 687         {
 688           ip4_sv_reass_add_trace (
 689             vm, node, NULL, from[(b - 1) - bufs], REASS_PASSTHROUGH,
 690             vnet_buffer (b0)->ip.reass.ip_proto,
 691             vnet_buffer (b0)->ip.reass.l4_src_port,
 692             vnet_buffer (b0)->ip.reass.l4_dst_port,
 693             vnet_buffer (b0)->ip.reass.l4_layer_truncated);
 694         }
 695
 696       n_left_from -= 1;
 697       next[0] = next0;
 698       next += 1;
 699     }
 700
 701   vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
 702                                frame->n_vectors);
 703
 704   goto done;
 705
 706 slow_path:
 707
 708   from += b - bufs;
 709
 710   while (n_left_from > 0)
 711     {
 712       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 713
 714       while (n_left_from > 0 && n_left_to_next > 0)
 715         {
 716           u32 bi0;
 717           vlib_buffer_t *b0;
 718           u32 next0;
 719           u32 error0 = IP4_ERROR_NONE;
 720
 721           bi0 = from[0];
 722           b0 = vlib_get_buffer (vm, bi0);
 723
 724           ip4_header_t *ip0 =
 725             (ip4_header_t *) u8_ptr_add (vlib_buffer_get_current (b0),
 726                                          (is_output_feature ? 1 : 0) *
 727                                          vnet_buffer (b0)->
 728                                          ip.save_rewrite_length);
 729           if (!ip4_get_fragment_more (ip0) && !ip4_get_fragment_offset (ip0))
 730             {
 731               // this is a regular packet - no fragmentation
 732               if (is_custom)
 733                 {
 734                   next0 = vnet_buffer (b0)->ip.reass.next_index;
 735                 }
 736               else
 737                 {
 738                   next0 = IP4_SV_REASSEMBLY_NEXT_INPUT;
 739                 }
 740               vnet_buffer (b0)->ip.reass.is_non_first_fragment = 0;
 741               vnet_buffer (b0)->ip.reass.ip_proto = ip0->protocol;
 742               if (l4_layer_truncated (ip0))
 743                 {
 744                   vnet_buffer (b0)->ip.reass.l4_layer_truncated = 1;
 745                   vnet_buffer (b0)->ip.reass.l4_src_port = 0;
 746                   vnet_buffer (b0)->ip.reass.l4_dst_port = 0;
 747                 }
 748               else
 749                 {
 750                   vnet_buffer (b0)->ip.reass.l4_layer_truncated = 0;
 751                   if (IP_PROTOCOL_TCP == ip0->protocol)
 752                     {
 753                       vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 754                         ((tcp_header_t *) (ip0 + 1))->flags;
 755                       vnet_buffer (b0)->ip.reass.tcp_ack_number =
 756                         ((tcp_header_t *) (ip0 + 1))->ack_number;
 757                       vnet_buffer (b0)->ip.reass.tcp_seq_number =
 758                         ((tcp_header_t *) (ip0 + 1))->seq_number;
 759                     }
 760                   else if (IP_PROTOCOL_ICMP == ip0->protocol)
 761                     {
 762                       vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 763                         ((icmp46_header_t *) (ip0 + 1))->type;
 764                     }
 765                   vnet_buffer (b0)->ip.reass.l4_src_port =
 766                     ip4_get_port (ip0, 1);
 767                   vnet_buffer (b0)->ip.reass.l4_dst_port =
 768                     ip4_get_port (ip0, 0);
 769                 }
 770               if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 771                 {
 772                   ip4_sv_reass_add_trace (
 773                     vm, node, NULL, bi0, REASS_PASSTHROUGH,
 774                     vnet_buffer (b0)->ip.reass.ip_proto,
 775                     vnet_buffer (b0)->ip.reass.l4_src_port,
 776                     vnet_buffer (b0)->ip.reass.l4_dst_port,
 777                     vnet_buffer (b0)->ip.reass.l4_layer_truncated);
 778                 }
 779               goto packet_enqueue;
 780             }
 781           const u32 fragment_first = ip4_get_fragment_offset_bytes (ip0);
 782           const u32 fragment_length =
 783             clib_net_to_host_u16 (ip0->length) - ip4_header_bytes (ip0);
 784           const u32 fragment_last = fragment_first + fragment_length - 1;
 785           if (fragment_first > fragment_last || fragment_first + fragment_length > UINT16_MAX - 20 || (fragment_length < 8 && ip4_get_fragment_more (ip0)))     // 8 is minimum frag length per RFC 791
 786             {
 787               next0 = IP4_SV_REASSEMBLY_NEXT_DROP;
 788               error0 = IP4_ERROR_REASS_MALFORMED_PACKET;
 789               b0->error = node->errors[error0];
 790               goto packet_enqueue;
 791             }
 792           ip4_sv_reass_kv_t kv;
 793           u8 do_handoff = 0;
 794
 795           kv.k.as_u64[0] =
 796             (u64) vec_elt (ip4_main.fib_index_by_sw_if_index,
 797                            vnet_buffer (b0)->sw_if_index[VLIB_RX]) |
 798             (u64) ip0->src_address.as_u32 << 32;
 799           kv.k.as_u64[1] =
 800             (u64) ip0->dst_address.
 801             as_u32 | (u64) ip0->fragment_id << 32 | (u64) ip0->protocol << 48;
 802
 803           ip4_sv_reass_t *reass =
 804             ip4_sv_reass_find_or_create (vm, rm, rt, &kv, &do_handoff);
 805
 806           if (PREDICT_FALSE (do_handoff))
 807             {
 808               next0 = IP4_SV_REASSEMBLY_NEXT_HANDOFF;
 809               vnet_buffer (b0)->ip.reass.owner_thread_index =
 810                 kv.v.thread_index;
 811               goto packet_enqueue;
 812             }
 813
 814           if (!reass)
 815             {
 816               next0 = IP4_SV_REASSEMBLY_NEXT_DROP;
 817               error0 = IP4_ERROR_REASS_LIMIT_REACHED;
 818               b0->error = node->errors[error0];
 819               goto packet_enqueue;
 820             }
 821
 822           if (reass->is_complete)
 823             {
 824               if (is_custom)
 825                 {
 826                   next0 = vnet_buffer (b0)->ip.reass.next_index;
 827                 }
 828               else
 829                 {
 830                   next0 = IP4_SV_REASSEMBLY_NEXT_INPUT;
 831                 }
 832               vnet_buffer (b0)->ip.reass.is_non_first_fragment =
 833                 ! !fragment_first;
 834               vnet_buffer (b0)->ip.reass.ip_proto = reass->ip_proto;
 835               vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 836                 reass->icmp_type_or_tcp_flags;
 837               vnet_buffer (b0)->ip.reass.tcp_ack_number =
 838                 reass->tcp_ack_number;
 839               vnet_buffer (b0)->ip.reass.tcp_seq_number =
 840                 reass->tcp_seq_number;
 841               vnet_buffer (b0)->ip.reass.l4_src_port = reass->l4_src_port;
 842               vnet_buffer (b0)->ip.reass.l4_dst_port = reass->l4_dst_port;
 843               if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 844                 {
 845                   ip4_sv_reass_add_trace (
 846                     vm, node, reass, bi0, REASS_FRAGMENT_FORWARD,
 847                     reass->ip_proto, reass->l4_src_port, reass->l4_dst_port,
 848                     vnet_buffer (b0)->ip.reass.l4_layer_truncated);
 849                 }
 850               goto packet_enqueue;
 851             }
 852
 853           ip4_sv_reass_rc_t rc =
 854             ip4_sv_reass_update (vm, node, rm, ip0, reass, bi0);
 855           u32 counter = ~0;
 856           switch (rc)
 857             {
 858             case IP4_SV_REASS_RC_OK:
 859               /* nothing to do here */
 860               break;
 861             case IP4_SV_REASS_RC_TOO_MANY_FRAGMENTS:
 862               counter = IP4_ERROR_REASS_FRAGMENT_CHAIN_TOO_LONG;
 863               break;
 864             case IP4_SV_REASS_RC_UNSUPP_IP_PROTO:
 865               counter = IP4_ERROR_REASS_UNSUPP_IP_PROT;
 866               break;
 867             }
 868           if (~0 != counter)
 869             {
 870               vlib_node_increment_counter (vm, node->node_index, counter, 1);
 871               ip4_sv_reass_free (vm, rm, rt, reass);
 872               goto next_packet;
 873             }
 874           if (reass->is_complete)
 875             {
 876               u32 idx;
 877               vec_foreach_index (idx, reass->cached_buffers)
 878               {
 879                 u32 bi0 = vec_elt (reass->cached_buffers, idx);
 880                 vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
 881                 ip0 =
 882                   (ip4_header_t *) u8_ptr_add (vlib_buffer_get_current (b0),
 883                                                (is_output_feature ? 1 : 0) *
 884                                                vnet_buffer (b0)->
 885                                                ip.save_rewrite_length);
 886                 u32 next0 = IP4_SV_REASSEMBLY_NEXT_INPUT;
 887                 if (is_feature)
 888                   {
 889                     vnet_feature_next (&next0, b0);
 890                   }
 891                 if (is_custom)
 892                   {
 893                     next0 = vnet_buffer (b0)->ip.reass.next_index;
 894                   }
 895                 if (0 == n_left_to_next)
 896                   {
 897                     vlib_put_next_frame (vm, node, next_index,
 898                                          n_left_to_next);
 899                     vlib_get_next_frame (vm, node, next_index, to_next,
 900                                          n_left_to_next);
 901                   }
 902                 to_next[0] = bi0;
 903                 to_next += 1;
 904                 n_left_to_next -= 1;
 905                 vnet_buffer (b0)->ip.reass.is_non_first_fragment =
 906                   ! !ip4_get_fragment_offset (ip0);
 907                 vnet_buffer (b0)->ip.reass.ip_proto = reass->ip_proto;
 908                 vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags =
 909                   reass->icmp_type_or_tcp_flags;
 910                 vnet_buffer (b0)->ip.reass.tcp_ack_number =
 911                   reass->tcp_ack_number;
 912                 vnet_buffer (b0)->ip.reass.tcp_seq_number =
 913                   reass->tcp_seq_number;
 914                 vnet_buffer (b0)->ip.reass.l4_src_port = reass->l4_src_port;
 915                 vnet_buffer (b0)->ip.reass.l4_dst_port = reass->l4_dst_port;
 916                 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 917                   {
 918                     ip4_sv_reass_add_trace (
 919                       vm, node, reass, bi0, REASS_FRAGMENT_FORWARD,
 920                       reass->ip_proto, reass->l4_src_port, reass->l4_dst_port,
 921                       vnet_buffer (b0)->ip.reass.l4_layer_truncated);
 922                   }
 923                 vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 924                                                  to_next, n_left_to_next, bi0,
 925                                                  next0);
 926               }
 927               vec_set_len (reass->cached_buffers,
 928                            0); // buffers are owned by frame now
 929             }
 930           goto next_packet;
 931
 932         packet_enqueue:
 933           to_next[0] = bi0;
 934           to_next += 1;
 935           n_left_to_next -= 1;
 936           if (is_feature && IP4_ERROR_NONE == error0)
 937             {
 938               b0 = vlib_get_buffer (vm, bi0);
 939               vnet_feature_next (&next0, b0);
 940             }
 941           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 942                                            to_next, n_left_to_next,
 943                                            bi0, next0);
 944
 945         next_packet:
 946           from += 1;
 947           n_left_from -= 1;
 948         }
 949
 950       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 951     }
 952
 953 done:
 954   clib_spinlock_unlock (&rt->lock);
 955   return frame->n_vectors;
 956 }
 957
 958 VLIB_NODE_FN (ip4_sv_reass_node) (vlib_main_t * vm,
 959                                   vlib_node_runtime_t * node,
 960                                   vlib_frame_t * frame)
 961 {
 962   return ip4_sv_reass_inline (vm, node, frame, false /* is_feature */ ,
 963                               false /* is_output_feature */ ,
 964                               false /* is_custom */ );
 965 }
 966
 967 /* *INDENT-OFF* */
 968 VLIB_REGISTER_NODE (ip4_sv_reass_node) = {
 969     .name = "ip4-sv-reassembly",
 970     .vector_size = sizeof (u32),
 971     .format_trace = format_ip4_sv_reass_trace,
 972     .n_errors = IP4_N_ERROR,
 973     .error_counters = ip4_error_counters,
 974     .n_next_nodes = IP4_SV_REASSEMBLY_N_NEXT,
 975     .next_nodes =
 976         {
 977                 [IP4_SV_REASSEMBLY_NEXT_INPUT] = "ip4-input",
 978                 [IP4_SV_REASSEMBLY_NEXT_DROP] = "ip4-drop",
 979                 [IP4_SV_REASSEMBLY_NEXT_HANDOFF] = "ip4-sv-reassembly-handoff",
 980
 981         },
 982 };
 983 /* *INDENT-ON* */
 984
 985 VLIB_NODE_FN (ip4_sv_reass_node_feature) (vlib_main_t * vm,
 986                                           vlib_node_runtime_t * node,
 987                                           vlib_frame_t * frame)
 988 {
 989   return ip4_sv_reass_inline (vm, node, frame, true /* is_feature */ ,
 990                               false /* is_output_feature */ ,
 991                               false /* is_custom */ );
 992 }
 993
 994 /* *INDENT-OFF* */
 995 VLIB_REGISTER_NODE (ip4_sv_reass_node_feature) = {
 996     .name = "ip4-sv-reassembly-feature",
 997     .vector_size = sizeof (u32),
 998     .format_trace = format_ip4_sv_reass_trace,
 999     .n_errors = IP4_N_ERROR,
1000     .error_counters = ip4_error_counters,
1001     .n_next_nodes = IP4_SV_REASSEMBLY_N_NEXT,
1002     .next_nodes =
1003         {
1004                 [IP4_SV_REASSEMBLY_NEXT_INPUT] = "ip4-input",
1005                 [IP4_SV_REASSEMBLY_NEXT_DROP] = "ip4-drop",
1006                 [IP4_SV_REASSEMBLY_NEXT_HANDOFF] = "ip4-sv-reass-feature-hoff",
1007         },
1008 };
1009 /* *INDENT-ON* */
1010
1011 /* *INDENT-OFF* */
1012 VNET_FEATURE_INIT (ip4_sv_reass_feature) = {
1013     .arc_name = "ip4-unicast",
1014     .node_name = "ip4-sv-reassembly-feature",
1015     .runs_before = VNET_FEATURES ("ip4-lookup"),
1016     .runs_after = 0,
1017 };
1018 /* *INDENT-ON* */
1019
1020 VLIB_NODE_FN (ip4_sv_reass_node_output_feature) (vlib_main_t * vm,
1021                                                  vlib_node_runtime_t * node,
1022                                                  vlib_frame_t * frame)
1023 {
1024   return ip4_sv_reass_inline (vm, node, frame, true /* is_feature */ ,
1025                               true /* is_output_feature */ ,
1026                               false /* is_custom */ );
1027 }
1028
1029
1030 /* *INDENT-OFF* */
1031 VLIB_REGISTER_NODE (ip4_sv_reass_node_output_feature) = {
1032     .name = "ip4-sv-reassembly-output-feature",
1033     .vector_size = sizeof (u32),
1034     .format_trace = format_ip4_sv_reass_trace,
1035     .n_errors = IP4_N_ERROR,
1036     .error_counters = ip4_error_counters,
1037     .n_next_nodes = IP4_SV_REASSEMBLY_N_NEXT,
1038     .next_nodes =
1039         {
1040                 [IP4_SV_REASSEMBLY_NEXT_INPUT] = "ip4-input",
1041                 [IP4_SV_REASSEMBLY_NEXT_DROP] = "ip4-drop",
1042                 [IP4_SV_REASSEMBLY_NEXT_HANDOFF] = "ip4-sv-reass-feature-hoff",
1043         },
1044 };
1045 /* *INDENT-ON* */
1046
1047 /* *INDENT-OFF* */
1048 VNET_FEATURE_INIT (ip4_sv_reass_output_feature) = {
1049     .arc_name = "ip4-output",
1050     .node_name = "ip4-sv-reassembly-output-feature",
1051     .runs_before = 0,
1052     .runs_after = 0,
1053 };
1054 /* *INDENT-ON* */
1055
1056 /* *INDENT-OFF* */
1057 VLIB_REGISTER_NODE (ip4_sv_reass_custom_node) = {
1058     .name = "ip4-sv-reassembly-custom-next",
1059     .vector_size = sizeof (u32),
1060     .format_trace = format_ip4_sv_reass_trace,
1061     .n_errors = IP4_N_ERROR,
1062     .error_counters = ip4_error_counters,
1063     .n_next_nodes = IP4_SV_REASSEMBLY_N_NEXT,
1064     .next_nodes =
1065         {
1066                 [IP4_SV_REASSEMBLY_NEXT_INPUT] = "ip4-input",
1067                 [IP4_SV_REASSEMBLY_NEXT_DROP] = "ip4-drop",
1068                 [IP4_SV_REASSEMBLY_NEXT_HANDOFF] = "ip4-sv-reassembly-handoff",
1069
1070         },
1071 };
1072 /* *INDENT-ON* */
1073
1074 VLIB_NODE_FN (ip4_sv_reass_custom_node) (vlib_main_t * vm,
1075                                          vlib_node_runtime_t * node,
1076                                          vlib_frame_t * frame)
1077 {
1078   return ip4_sv_reass_inline (vm, node, frame, false /* is_feature */ ,
1079                               false /* is_output_feature */ ,
1080                               true /* is_custom */ );
1081 }
1082
1083 #ifndef CLIB_MARCH_VARIANT
1084 always_inline u32
1085 ip4_sv_reass_get_nbuckets ()
1086 {
1087   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
1088   u32 nbuckets;
1089   u8 i;
1090
1091   nbuckets = (u32) (rm->max_reass_n / IP4_SV_REASS_HT_LOAD_FACTOR);
1092
1093   for (i = 0; i < 31; i++)
1094     if ((1 << i) >= nbuckets)
1095       break;
1096   nbuckets = 1 << i;
1097
1098   return nbuckets;
1099 }
1100 #endif /* CLIB_MARCH_VARIANT */
1101
1102 typedef enum
1103 {
1104   IP4_EVENT_CONFIG_CHANGED = 1,
1105 } ip4_sv_reass_event_t;
1106
1107 typedef struct
1108 {
1109   int failure;
1110   clib_bihash_16_8_t *new_hash;
1111 } ip4_rehash_cb_ctx;
1112
1113 #ifndef CLIB_MARCH_VARIANT
1114 static int
1115 ip4_rehash_cb (clib_bihash_kv_16_8_t * kv, void *_ctx)
1116 {
1117   ip4_rehash_cb_ctx *ctx = _ctx;
1118   if (clib_bihash_add_del_16_8 (ctx->new_hash, kv, 1))
1119     {
1120       ctx->failure = 1;
1121     }
1122   return (BIHASH_WALK_CONTINUE);
1123 }
1124
1125 static void
1126 ip4_sv_reass_set_params (u32 timeout_ms, u32 max_reassemblies,
1127                          u32 max_reassembly_length,
1128                          u32 expire_walk_interval_ms)
1129 {
1130   ip4_sv_reass_main.timeout_ms = timeout_ms;
1131   ip4_sv_reass_main.timeout = (f64) timeout_ms / (f64) MSEC_PER_SEC;
1132   ip4_sv_reass_main.max_reass_n = max_reassemblies;
1133   ip4_sv_reass_main.max_reass_len = max_reassembly_length;
1134   ip4_sv_reass_main.expire_walk_interval_ms = expire_walk_interval_ms;
1135 }
1136
1137 vnet_api_error_t
1138 ip4_sv_reass_set (u32 timeout_ms, u32 max_reassemblies,
1139                   u32 max_reassembly_length, u32 expire_walk_interval_ms)
1140 {
1141   u32 old_nbuckets = ip4_sv_reass_get_nbuckets ();
1142   ip4_sv_reass_set_params (timeout_ms, max_reassemblies,
1143                            max_reassembly_length, expire_walk_interval_ms);
1144   vlib_process_signal_event (ip4_sv_reass_main.vlib_main,
1145                              ip4_sv_reass_main.ip4_sv_reass_expire_node_idx,
1146                              IP4_EVENT_CONFIG_CHANGED, 0);
1147   u32 new_nbuckets = ip4_sv_reass_get_nbuckets ();
1148   if (ip4_sv_reass_main.max_reass_n > 0 && new_nbuckets > old_nbuckets)
1149     {
1150       clib_bihash_16_8_t new_hash;
1151       clib_memset (&new_hash, 0, sizeof (new_hash));
1152       ip4_rehash_cb_ctx ctx;
1153       ctx.failure = 0;
1154       ctx.new_hash = &new_hash;
1155       clib_bihash_init_16_8 (&new_hash, "ip4-dr", new_nbuckets,
1156                              new_nbuckets * 1024);
1157       clib_bihash_foreach_key_value_pair_16_8 (&ip4_sv_reass_main.hash,
1158                                                ip4_rehash_cb, &ctx);
1159       if (ctx.failure)
1160         {
1161           clib_bihash_free_16_8 (&new_hash);
1162           return -1;
1163         }
1164       else
1165         {
1166           clib_bihash_free_16_8 (&ip4_sv_reass_main.hash);
1167           clib_memcpy_fast (&ip4_sv_reass_main.hash, &new_hash,
1168                             sizeof (ip4_sv_reass_main.hash));
1169           clib_bihash_copied (&ip4_sv_reass_main.hash, &new_hash);
1170         }
1171     }
1172   return 0;
1173 }
1174
1175 vnet_api_error_t
1176 ip4_sv_reass_get (u32 * timeout_ms, u32 * max_reassemblies,
1177                   u32 * max_reassembly_length, u32 * expire_walk_interval_ms)
1178 {
1179   *timeout_ms = ip4_sv_reass_main.timeout_ms;
1180   *max_reassemblies = ip4_sv_reass_main.max_reass_n;
1181   *max_reassembly_length = ip4_sv_reass_main.max_reass_len;
1182   *expire_walk_interval_ms = ip4_sv_reass_main.expire_walk_interval_ms;
1183   return 0;
1184 }
1185
1186 static clib_error_t *
1187 ip4_sv_reass_init_function (vlib_main_t * vm)
1188 {
1189   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
1190   clib_error_t *error = 0;
1191   u32 nbuckets;
1192   vlib_node_t *node;
1193
1194   rm->vlib_main = vm;
1195   rm->vnet_main = vnet_get_main ();
1196
1197   vec_validate (rm->per_thread_data, vlib_num_workers ());
1198   ip4_sv_reass_per_thread_t *rt;
1199   vec_foreach (rt, rm->per_thread_data)
1200   {
1201     clib_spinlock_init (&rt->lock);
1202     pool_alloc (rt->pool, rm->max_reass_n);
1203     rt->lru_first = rt->lru_last = ~0;
1204   }
1205
1206   node = vlib_get_node_by_name (vm, (u8 *) "ip4-sv-reassembly-expire-walk");
1207   ASSERT (node);
1208   rm->ip4_sv_reass_expire_node_idx = node->index;
1209
1210   ip4_sv_reass_set_params (IP4_SV_REASS_TIMEOUT_DEFAULT_MS,
1211                            IP4_SV_REASS_MAX_REASSEMBLIES_DEFAULT,
1212                            IP4_SV_REASS_MAX_REASSEMBLY_LENGTH_DEFAULT,
1213                            IP4_SV_REASS_EXPIRE_WALK_INTERVAL_DEFAULT_MS);
1214
1215   nbuckets = ip4_sv_reass_get_nbuckets ();
1216   clib_bihash_init_16_8 (&rm->hash, "ip4-dr", nbuckets, nbuckets * 1024);
1217
1218   node = vlib_get_node_by_name (vm, (u8 *) "ip4-drop");
1219   ASSERT (node);
1220   rm->ip4_drop_idx = node->index;
1221
1222   rm->fq_index = vlib_frame_queue_main_init (ip4_sv_reass_node.index, 0);
1223   rm->fq_feature_index =
1224     vlib_frame_queue_main_init (ip4_sv_reass_node_feature.index, 0);
1225
1226   rm->feature_use_refcount_per_intf = NULL;
1227   rm->output_feature_use_refcount_per_intf = NULL;
1228
1229   return error;
1230 }
1231
1232 VLIB_INIT_FUNCTION (ip4_sv_reass_init_function);
1233 #endif /* CLIB_MARCH_VARIANT */
1234
1235 static uword
1236 ip4_sv_reass_walk_expired (vlib_main_t *vm,
1237                            CLIB_UNUSED (vlib_node_runtime_t *node),
1238                            CLIB_UNUSED (vlib_frame_t *f))
1239 {
1240   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
1241   uword event_type, *event_data = 0;
1242
1243   while (true)
1244     {
1245       vlib_process_wait_for_event_or_clock (vm,
1246                                             (f64)
1247                                             rm->expire_walk_interval_ms /
1248                                             (f64) MSEC_PER_SEC);
1249       event_type = vlib_process_get_events (vm, &event_data);
1250
1251       switch (event_type)
1252         {
1253         case ~0:
1254           /* no events => timeout */
1255           /* fallthrough */
1256         case IP4_EVENT_CONFIG_CHANGED:
1257           /* nothing to do here */
1258           break;
1259         default:
1260           clib_warning ("BUG: event type 0x%wx", event_type);
1261           break;
1262         }
1263       f64 now = vlib_time_now (vm);
1264
1265       ip4_sv_reass_t *reass;
1266       int *pool_indexes_to_free = NULL;
1267
1268       uword thread_index = 0;
1269       int index;
1270       const uword nthreads = vlib_num_workers () + 1;
1271       for (thread_index = 0; thread_index < nthreads; ++thread_index)
1272         {
1273           ip4_sv_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1274           clib_spinlock_lock (&rt->lock);
1275
1276           vec_reset_length (pool_indexes_to_free);
1277           /* *INDENT-OFF* */
1278           pool_foreach_index (index, rt->pool)  {
1279                                 reass = pool_elt_at_index (rt->pool, index);
1280                                 if (now > reass->last_heard + rm->timeout)
1281                                   {
1282                                     vec_add1 (pool_indexes_to_free, index);
1283                                   }
1284                               }
1285           /* *INDENT-ON* */
1286           int *i;
1287           /* *INDENT-OFF* */
1288           vec_foreach (i, pool_indexes_to_free)
1289           {
1290             ip4_sv_reass_t *reass = pool_elt_at_index (rt->pool, i[0]);
1291             ip4_sv_reass_free (vm, rm, rt, reass);
1292           }
1293           /* *INDENT-ON* */
1294
1295           clib_spinlock_unlock (&rt->lock);
1296         }
1297
1298       vec_free (pool_indexes_to_free);
1299       if (event_data)
1300         {
1301           vec_set_len (event_data, 0);
1302         }
1303     }
1304
1305   return 0;
1306 }
1307
1308 /* *INDENT-OFF* */
1309 VLIB_REGISTER_NODE (ip4_sv_reass_expire_node) = {
1310   .function = ip4_sv_reass_walk_expired,
1311   .type = VLIB_NODE_TYPE_PROCESS,
1312   .name = "ip4-sv-reassembly-expire-walk",
1313   .format_trace = format_ip4_sv_reass_trace,
1314   .n_errors = IP4_N_ERROR,
1315   .error_counters = ip4_error_counters,
1316 };
1317 /* *INDENT-ON* */
1318
1319 static u8 *
1320 format_ip4_sv_reass_key (u8 * s, va_list * args)
1321 {
1322   ip4_sv_reass_key_t *key = va_arg (*args, ip4_sv_reass_key_t *);
1323   s =
1324     format (s, "fib_index: %u, src: %U, dst: %U, frag_id: %u, proto: %u",
1325             key->fib_index, format_ip4_address, &key->src, format_ip4_address,
1326             &key->dst, clib_net_to_host_u16 (key->frag_id), key->proto);
1327   return s;
1328 }
1329
1330 static u8 *
1331 format_ip4_sv_reass (u8 * s, va_list * args)
1332 {
1333   vlib_main_t *vm = va_arg (*args, vlib_main_t *);
1334   ip4_sv_reass_t *reass = va_arg (*args, ip4_sv_reass_t *);
1335
1336   s = format (s, "ID: %lu, key: %U trace_op_counter: %u\n",
1337               reass->id, format_ip4_sv_reass_key, &reass->key,
1338               reass->trace_op_counter);
1339
1340   vlib_buffer_t *b;
1341   u32 *bip;
1342   u32 counter = 0;
1343   vec_foreach (bip, reass->cached_buffers)
1344   {
1345     u32 bi = *bip;
1346     do
1347       {
1348         b = vlib_get_buffer (vm, bi);
1349         s = format (s, "  #%03u: bi: %u, ", counter, bi);
1350         ++counter;
1351         bi = b->next_buffer;
1352       }
1353     while (b->flags & VLIB_BUFFER_NEXT_PRESENT);
1354   }
1355   return s;
1356 }
1357
1358 static clib_error_t *
1359 show_ip4_reass (vlib_main_t * vm,
1360                 unformat_input_t * input,
1361                 CLIB_UNUSED (vlib_cli_command_t * lmd))
1362 {
1363   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
1364
1365   vlib_cli_output (vm, "---------------------");
1366   vlib_cli_output (vm, "IP4 reassembly status");
1367   vlib_cli_output (vm, "---------------------");
1368   bool details = false;
1369   if (unformat (input, "details"))
1370     {
1371       details = true;
1372     }
1373
1374   u32 sum_reass_n = 0;
1375   ip4_sv_reass_t *reass;
1376   uword thread_index;
1377   const uword nthreads = vlib_num_workers () + 1;
1378   for (thread_index = 0; thread_index < nthreads; ++thread_index)
1379     {
1380       ip4_sv_reass_per_thread_t *rt = &rm->per_thread_data[thread_index];
1381       clib_spinlock_lock (&rt->lock);
1382       if (details)
1383         {
1384           /* *INDENT-OFF* */
1385           pool_foreach (reass, rt->pool) {
1386             vlib_cli_output (vm, "%U", format_ip4_sv_reass, vm, reass);
1387           }
1388           /* *INDENT-ON* */
1389         }
1390       sum_reass_n += rt->reass_n;
1391       clib_spinlock_unlock (&rt->lock);
1392     }
1393   vlib_cli_output (vm, "---------------------");
1394   vlib_cli_output (vm, "Current IP4 reassemblies count: %lu\n",
1395                    (long unsigned) sum_reass_n);
1396   vlib_cli_output (vm,
1397                    "Maximum configured concurrent shallow virtual IP4 reassemblies per worker-thread: %lu\n",
1398                    (long unsigned) rm->max_reass_n);
1399   vlib_cli_output (vm,
1400                    "Maximum configured amount of fragments per shallow "
1401                    "virtual IP4 reassembly: %lu\n",
1402                    (long unsigned) rm->max_reass_len);
1403   vlib_cli_output (vm,
1404                    "Maximum configured shallow virtual IP4 reassembly timeout: %lums\n",
1405                    (long unsigned) rm->timeout_ms);
1406   vlib_cli_output (vm,
1407                    "Maximum configured shallow virtual IP4 reassembly expire walk interval: %lums\n",
1408                    (long unsigned) rm->expire_walk_interval_ms);
1409   return 0;
1410 }
1411
1412 /* *INDENT-OFF* */
1413 VLIB_CLI_COMMAND (show_ip4_sv_reass_cmd, static) = {
1414     .path = "show ip4-sv-reassembly",
1415     .short_help = "show ip4-sv-reassembly [details]",
1416     .function = show_ip4_reass,
1417 };
1418 /* *INDENT-ON* */
1419
1420 #ifndef CLIB_MARCH_VARIANT
1421 vnet_api_error_t
1422 ip4_sv_reass_enable_disable (u32 sw_if_index, u8 enable_disable)
1423 {
1424   return ip4_sv_reass_enable_disable_with_refcnt (sw_if_index,
1425                                                   enable_disable);
1426 }
1427 #endif /* CLIB_MARCH_VARIANT */
1428
1429
1430 #define foreach_ip4_sv_reass_handoff_error                       \
1431 _(CONGESTION_DROP, "congestion drop")
1432
1433
1434 typedef enum
1435 {
1436 #define _(sym,str) IP4_SV_REASSEMBLY_HANDOFF_ERROR_##sym,
1437   foreach_ip4_sv_reass_handoff_error
1438 #undef _
1439     IP4_SV_REASSEMBLY_HANDOFF_N_ERROR,
1440 } ip4_sv_reass_handoff_error_t;
1441
1442 static char *ip4_sv_reass_handoff_error_strings[] = {
1443 #define _(sym,string) string,
1444   foreach_ip4_sv_reass_handoff_error
1445 #undef _
1446 };
1447
1448 typedef struct
1449 {
1450   u32 next_worker_index;
1451 } ip4_sv_reass_handoff_trace_t;
1452
1453 static u8 *
1454 format_ip4_sv_reass_handoff_trace (u8 * s, va_list * args)
1455 {
1456   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1457   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1458   ip4_sv_reass_handoff_trace_t *t =
1459     va_arg (*args, ip4_sv_reass_handoff_trace_t *);
1460
1461   s =
1462     format (s, "ip4-sv-reassembly-handoff: next-worker %d",
1463             t->next_worker_index);
1464
1465   return s;
1466 }
1467
1468 always_inline uword
1469 ip4_sv_reass_handoff_node_inline (vlib_main_t * vm,
1470                                   vlib_node_runtime_t * node,
1471                                   vlib_frame_t * frame, bool is_feature)
1472 {
1473   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
1474
1475   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1476   u32 n_enq, n_left_from, *from;
1477   u16 thread_indices[VLIB_FRAME_SIZE], *ti;
1478   u32 fq_index;
1479
1480   from = vlib_frame_vector_args (frame);
1481   n_left_from = frame->n_vectors;
1482   vlib_get_buffers (vm, from, bufs, n_left_from);
1483
1484   b = bufs;
1485   ti = thread_indices;
1486
1487   fq_index = (is_feature) ? rm->fq_feature_index : rm->fq_index;
1488
1489   while (n_left_from > 0)
1490     {
1491       ti[0] = vnet_buffer (b[0])->ip.reass.owner_thread_index;
1492
1493       if (PREDICT_FALSE
1494           ((node->flags & VLIB_NODE_FLAG_TRACE)
1495            && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
1496         {
1497           ip4_sv_reass_handoff_trace_t *t =
1498             vlib_add_trace (vm, node, b[0], sizeof (*t));
1499           t->next_worker_index = ti[0];
1500         }
1501
1502       n_left_from -= 1;
1503       ti += 1;
1504       b += 1;
1505     }
1506   n_enq = vlib_buffer_enqueue_to_thread (vm, node, fq_index, from,
1507                                          thread_indices, frame->n_vectors, 1);
1508
1509   if (n_enq < frame->n_vectors)
1510     vlib_node_increment_counter (vm, node->node_index,
1511                                  IP4_SV_REASSEMBLY_HANDOFF_ERROR_CONGESTION_DROP,
1512                                  frame->n_vectors - n_enq);
1513   return frame->n_vectors;
1514 }
1515
1516 VLIB_NODE_FN (ip4_sv_reass_handoff_node) (vlib_main_t * vm,
1517                                           vlib_node_runtime_t * node,
1518                                           vlib_frame_t * frame)
1519 {
1520   return ip4_sv_reass_handoff_node_inline (vm, node, frame,
1521                                            false /* is_feature */ );
1522 }
1523
1524
1525 /* *INDENT-OFF* */
1526 VLIB_REGISTER_NODE (ip4_sv_reass_handoff_node) = {
1527   .name = "ip4-sv-reassembly-handoff",
1528   .vector_size = sizeof (u32),
1529   .n_errors = ARRAY_LEN(ip4_sv_reass_handoff_error_strings),
1530   .error_strings = ip4_sv_reass_handoff_error_strings,
1531   .format_trace = format_ip4_sv_reass_handoff_trace,
1532
1533   .n_next_nodes = 1,
1534
1535   .next_nodes = {
1536     [0] = "error-drop",
1537   },
1538 };
1539 /* *INDENT-ON* */
1540
1541
1542 /* *INDENT-OFF* */
1543 VLIB_NODE_FN (ip4_sv_reass_feature_handoff_node) (vlib_main_t * vm,
1544                                                     vlib_node_runtime_t *
1545                                                     node,
1546                                                     vlib_frame_t * frame)
1547 {
1548   return ip4_sv_reass_handoff_node_inline (vm, node, frame,
1549                                              true /* is_feature */ );
1550 }
1551 /* *INDENT-ON* */
1552
1553
1554 /* *INDENT-OFF* */
1555 VLIB_REGISTER_NODE (ip4_sv_reass_feature_handoff_node) = {
1556   .name = "ip4-sv-reass-feature-hoff",
1557   .vector_size = sizeof (u32),
1558   .n_errors = ARRAY_LEN(ip4_sv_reass_handoff_error_strings),
1559   .error_strings = ip4_sv_reass_handoff_error_strings,
1560   .format_trace = format_ip4_sv_reass_handoff_trace,
1561
1562   .n_next_nodes = 1,
1563
1564   .next_nodes = {
1565     [0] = "error-drop",
1566   },
1567 };
1568 /* *INDENT-ON* */
1569
1570 #ifndef CLIB_MARCH_VARIANT
1571 int
1572 ip4_sv_reass_enable_disable_with_refcnt (u32 sw_if_index, int is_enable)
1573 {
1574   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
1575   vec_validate (rm->feature_use_refcount_per_intf, sw_if_index);
1576   if (is_enable)
1577     {
1578       if (!rm->feature_use_refcount_per_intf[sw_if_index])
1579         {
1580           ++rm->feature_use_refcount_per_intf[sw_if_index];
1581           return vnet_feature_enable_disable ("ip4-unicast",
1582                                               "ip4-sv-reassembly-feature",
1583                                               sw_if_index, 1, 0, 0);
1584         }
1585       ++rm->feature_use_refcount_per_intf[sw_if_index];
1586     }
1587   else
1588     {
1589       if (rm->feature_use_refcount_per_intf[sw_if_index])
1590         --rm->feature_use_refcount_per_intf[sw_if_index];
1591       if (!rm->feature_use_refcount_per_intf[sw_if_index])
1592         return vnet_feature_enable_disable ("ip4-unicast",
1593                                             "ip4-sv-reassembly-feature",
1594                                             sw_if_index, 0, 0, 0);
1595     }
1596   return 0;
1597 }
1598
1599 uword
1600 ip4_sv_reass_custom_register_next_node (uword node_index)
1601 {
1602   return vlib_node_add_next (vlib_get_main (), ip4_sv_reass_custom_node.index,
1603                              node_index);
1604 }
1605
1606 int
1607 ip4_sv_reass_output_enable_disable_with_refcnt (u32 sw_if_index,
1608                                                 int is_enable)
1609 {
1610   ip4_sv_reass_main_t *rm = &ip4_sv_reass_main;
1611   vec_validate (rm->output_feature_use_refcount_per_intf, sw_if_index);
1612   if (is_enable)
1613     {
1614       if (!rm->output_feature_use_refcount_per_intf[sw_if_index])
1615         {
1616           ++rm->output_feature_use_refcount_per_intf[sw_if_index];
1617           return vnet_feature_enable_disable ("ip4-output",
1618                                               "ip4-sv-reassembly-output-feature",
1619                                               sw_if_index, 1, 0, 0);
1620         }
1621       ++rm->output_feature_use_refcount_per_intf[sw_if_index];
1622     }
1623   else
1624     {
1625       if (rm->output_feature_use_refcount_per_intf[sw_if_index])
1626         --rm->output_feature_use_refcount_per_intf[sw_if_index];
1627       if (!rm->output_feature_use_refcount_per_intf[sw_if_index])
1628         return vnet_feature_enable_disable ("ip4-output",
1629                                             "ip4-sv-reassembly-output-feature",
1630                                             sw_if_index, 0, 0, 0);
1631     }
1632   return 0;
1633 }
1634 #endif
1635
1636 /*
1637  * fd.io coding-style-patch-verification: ON
1638  *
1639  * Local Variables:
1640  * eval: (c-set-style "gnu")
1641  * End:
1642  */