in2out.c revision 0d75f783
1/*
2 * Copyright (c) 2016 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 * @file
17 * @brief NAT44 inside to outside network translation
18 */
19
20#include <vlib/vlib.h>
21#include <vnet/vnet.h>
22#include <vnet/pg/pg.h>
23
24#include <vnet/ip/ip.h>
25#include <vnet/ethernet/ethernet.h>
26#include <vnet/fib/ip4_fib.h>
27#include <nat/nat.h>
28#include <nat/nat_ipfix_logging.h>
29#include <nat/nat_reass.h>
30#include <nat/nat_inlines.h>
31#include <nat/nat_syslog.h>
32#include <nat/nat_ha.h>
33
34#include <vppinfra/hash.h>
35#include <vppinfra/error.h>
36#include <vppinfra/elog.h>
37
38typedef struct
39{
40  u32 sw_if_index;
41  u32 next_index;
42  u32 session_index;
43  u32 is_slow_path;
44} snat_in2out_trace_t;
45
46/* packet trace format function */
47static u8 *
48format_snat_in2out_trace (u8 * s, va_list * args)
49{
50  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
51  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
52  snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
53  char *tag;
54
55  tag = t->is_slow_path ? "NAT44_IN2OUT_SLOW_PATH" : "NAT44_IN2OUT_FAST_PATH";
56
57  s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
58	      t->sw_if_index, t->next_index, t->session_index);
59
60  return s;
61}
62
63static u8 *
64format_snat_in2out_fast_trace (u8 * s, va_list * args)
65{
66  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
67  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
68  snat_in2out_trace_t *t = va_arg (*args, snat_in2out_trace_t *);
69
70  s = format (s, "NAT44_IN2OUT_FAST: sw_if_index %d, next index %d",
71	      t->sw_if_index, t->next_index);
72
73  return s;
74}
75
76#define foreach_snat_in2out_error                       \
77_(UNSUPPORTED_PROTOCOL, "unsupported protocol")         \
78_(IN2OUT_PACKETS, "good in2out packets processed")      \
79_(OUT_OF_PORTS, "out of ports")                         \
80_(BAD_OUTSIDE_FIB, "outside VRF ID not found")          \
81_(BAD_ICMP_TYPE, "unsupported ICMP type")               \
82_(NO_TRANSLATION, "no translation")                     \
83_(MAX_SESSIONS_EXCEEDED, "maximum sessions exceeded")   \
84_(DROP_FRAGMENT, "drop fragment")                       \
85_(MAX_REASS, "maximum reassemblies exceeded")           \
86_(MAX_FRAG, "maximum fragments per reassembly exceeded")\
87_(TCP_PACKETS, "TCP packets")                           \
88_(UDP_PACKETS, "UDP packets")                           \
89_(ICMP_PACKETS, "ICMP packets")                         \
90_(OTHER_PACKETS, "other protocol packets")              \
91_(FRAGMENTS, "fragments")                               \
92_(CACHED_FRAGMENTS, "cached fragments")                 \
93_(PROCESSED_FRAGMENTS, "processed fragments")
94
95typedef enum
96{
97#define _(sym,str) SNAT_IN2OUT_ERROR_##sym,
98  foreach_snat_in2out_error
99#undef _
100    SNAT_IN2OUT_N_ERROR,
101} snat_in2out_error_t;
102
103static char *snat_in2out_error_strings[] = {
104#define _(sym,string) string,
105  foreach_snat_in2out_error
106#undef _
107};
108
109typedef enum
110{
111  SNAT_IN2OUT_NEXT_LOOKUP,
112  SNAT_IN2OUT_NEXT_DROP,
113  SNAT_IN2OUT_NEXT_ICMP_ERROR,
114  SNAT_IN2OUT_NEXT_SLOW_PATH,
115  SNAT_IN2OUT_NEXT_REASS,
116  SNAT_IN2OUT_N_NEXT,
117} snat_in2out_next_t;
118
119static inline int
120snat_not_translate (snat_main_t * sm, vlib_node_runtime_t * node,
121		    u32 sw_if_index0, ip4_header_t * ip0, u32 proto0,
122		    u32 rx_fib_index0, u32 thread_index)
123{
124  udp_header_t *udp0 = ip4_next_header (ip0);
125  snat_session_key_t key0, sm0;
126  clib_bihash_kv_8_8_t kv0, value0;
127
128  key0.addr = ip0->dst_address;
129  key0.port = udp0->dst_port;
130  key0.protocol = proto0;
131  key0.fib_index = sm->outside_fib_index;
132  kv0.key = key0.as_u64;
133
134  /* NAT packet aimed at external address if */
135  /* has active sessions */
136  if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].out2in, &kv0,
137			      &value0))
138    {
139      /* or is static mappings */
140      if (!snat_static_mapping_match (sm, key0, &sm0, 1, 0, 0, 0, 0, 0))
141	return 0;
142    }
143  else
144    return 0;
145
146  if (sm->forwarding_enabled)
147    return 1;
148
149  return snat_not_translate_fast (sm, node, sw_if_index0, ip0, proto0,
150				  rx_fib_index0);
151}
152
153static inline int
154nat_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip0,
155				  u32 proto0, u16 src_port, u16 dst_port,
156				  u32 thread_index, u32 sw_if_index)
157{
158  snat_session_key_t key0;
159  clib_bihash_kv_8_8_t kv0, value0;
160  snat_interface_t *i;
161
162  /* src NAT check */
163  key0.addr = ip0->src_address;
164  key0.port = src_port;
165  key0.protocol = proto0;
166  key0.fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
167  kv0.key = key0.as_u64;
168
169  if (!clib_bihash_search_8_8
170      (&sm->per_thread_data[thread_index].out2in, &kv0, &value0))
171    return 1;
172
173  /* dst NAT check */
174  key0.addr = ip0->dst_address;
175  key0.port = dst_port;
176  key0.protocol = proto0;
177  kv0.key = key0.as_u64;
178  if (!clib_bihash_search_8_8
179      (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
180    {
181      /* hairpinning */
182    /* *INDENT-OFF* */
183    pool_foreach (i, sm->output_feature_interfaces,
184    ({
185      if ((nat_interface_is_inside(i)) && (sw_if_index == i->sw_if_index))
186        return 0;
187    }));
188    /* *INDENT-ON* */
189      return 1;
190    }
191
192  return 0;
193}
194
195#ifndef CLIB_MARCH_VARIANT
196int
197nat44_i2o_is_idle_session_cb (clib_bihash_kv_8_8_t * kv, void *arg)
198{
199  snat_main_t *sm = &snat_main;
200  nat44_is_idle_session_ctx_t *ctx = arg;
201  snat_session_t *s;
202  u64 sess_timeout_time;
203  snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
204						       ctx->thread_index);
205  clib_bihash_kv_8_8_t s_kv;
206
207  s = pool_elt_at_index (tsm->sessions, kv->value);
208  sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
209  if (ctx->now >= sess_timeout_time)
210    {
211      s_kv.key = s->out2in.as_u64;
212      if (clib_bihash_add_del_8_8 (&tsm->out2in, &s_kv, 0))
213	nat_elog_warn ("out2in key del failed");
214
215      snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
216					   s->in2out.addr.as_u32,
217					   s->out2in.addr.as_u32,
218					   s->in2out.protocol,
219					   s->in2out.port,
220					   s->out2in.port,
221					   s->in2out.fib_index);
222
223      nat_syslog_nat44_apmdel (s->user_index, s->in2out.fib_index,
224			       &s->in2out.addr, s->in2out.port,
225			       &s->out2in.addr, s->out2in.port,
226			       s->in2out.protocol);
227
228      nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
229		   s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
230		   ctx->thread_index);
231
232      if (!snat_is_session_static (s))
233	snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
234					    &s->out2in);
235
236      nat44_delete_session (sm, s, ctx->thread_index);
237      return 1;
238    }
239
240  return 0;
241}
242#endif
243
244static u32
245slow_path (snat_main_t * sm, vlib_buffer_t * b0,
246	   ip4_header_t * ip0,
247	   u32 rx_fib_index0,
248	   snat_session_key_t * key0,
249	   snat_session_t ** sessionp,
250	   vlib_node_runtime_t * node, u32 next0, u32 thread_index, f64 now)
251{
252  snat_user_t *u;
253  snat_session_t *s = 0;
254  clib_bihash_kv_8_8_t kv0;
255  snat_session_key_t key1;
256  udp_header_t *udp0 = ip4_next_header (ip0);
257  u8 is_sm = 0;
258  nat_outside_fib_t *outside_fib;
259  fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
260  u8 identity_nat;
261  fib_prefix_t pfx = {
262    .fp_proto = FIB_PROTOCOL_IP4,
263    .fp_len = 32,
264    .fp_addr = {
265		.ip4.as_u32 = ip0->dst_address.as_u32,
266		},
267  };
268  nat44_is_idle_session_ctx_t ctx0;
269
270  if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
271    {
272      b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_SESSIONS_EXCEEDED];
273      nat_ipfix_logging_max_sessions (thread_index, sm->max_translations);
274      nat_elog_notice ("maximum sessions exceeded");
275      return SNAT_IN2OUT_NEXT_DROP;
276    }
277
278  key1.protocol = key0->protocol;
279
280  /* First try to match static mapping by local address and port */
281  if (snat_static_mapping_match
282      (sm, *key0, &key1, 0, 0, 0, 0, 0, &identity_nat))
283    {
284      /* Try to create dynamic translation */
285      if (snat_alloc_outside_address_and_port (sm->addresses, rx_fib_index0,
286					       thread_index, &key1,
287					       sm->port_per_thread,
288					       sm->per_thread_data
289					       [thread_index].snat_thread_index))
290	{
291	  b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
292	  return SNAT_IN2OUT_NEXT_DROP;
293	}
294    }
295  else
296    {
297      if (PREDICT_FALSE (identity_nat))
298	{
299	  *sessionp = s;
300	  return next0;
301	}
302
303      is_sm = 1;
304    }
305
306  u = nat_user_get_or_create (sm, &ip0->src_address, rx_fib_index0,
307			      thread_index);
308  if (!u)
309    {
310      nat_elog_warn ("create NAT user failed");
311      return SNAT_IN2OUT_NEXT_DROP;
312    }
313
314  s = nat_session_alloc_or_recycle (sm, u, thread_index, now);
315  if (!s)
316    {
317      nat44_delete_user_with_no_session (sm, u, thread_index);
318      nat_elog_warn ("create NAT session failed");
319      return SNAT_IN2OUT_NEXT_DROP;
320    }
321
322  if (is_sm)
323    s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
324  user_session_increment (sm, u, is_sm);
325  s->in2out = *key0;
326  s->out2in = key1;
327  s->out2in.protocol = key0->protocol;
328  s->out2in.fib_index = sm->outside_fib_index;
329  switch (vec_len (sm->outside_fibs))
330    {
331    case 0:
332      s->out2in.fib_index = sm->outside_fib_index;
333      break;
334    case 1:
335      s->out2in.fib_index = sm->outside_fibs[0].fib_index;
336      break;
337    default:
338      /* *INDENT-OFF* */
339      vec_foreach (outside_fib, sm->outside_fibs)
340        {
341          fei = fib_table_lookup (outside_fib->fib_index, &pfx);
342          if (FIB_NODE_INDEX_INVALID != fei)
343            {
344              if (fib_entry_get_resolving_interface (fei) != ~0)
345                {
346                  s->out2in.fib_index = outside_fib->fib_index;
347                  break;
348                }
349            }
350        }
351      /* *INDENT-ON* */
352      break;
353    }
354  s->ext_host_addr.as_u32 = ip0->dst_address.as_u32;
355  s->ext_host_port = udp0->dst_port;
356  *sessionp = s;
357
358  /* Add to translation hashes */
359  ctx0.now = now;
360  ctx0.thread_index = thread_index;
361  kv0.key = s->in2out.as_u64;
362  kv0.value = s - sm->per_thread_data[thread_index].sessions;
363  if (clib_bihash_add_or_overwrite_stale_8_8
364      (&sm->per_thread_data[thread_index].in2out, &kv0,
365       nat44_i2o_is_idle_session_cb, &ctx0))
366    nat_elog_notice ("in2out key add failed");
367
368  kv0.key = s->out2in.as_u64;
369  kv0.value = s - sm->per_thread_data[thread_index].sessions;
370
371  if (clib_bihash_add_or_overwrite_stale_8_8
372      (&sm->per_thread_data[thread_index].out2in, &kv0,
373       nat44_o2i_is_idle_session_cb, &ctx0))
374    nat_elog_notice ("out2in key add failed");
375
376  /* log NAT event */
377  snat_ipfix_logging_nat44_ses_create (thread_index,
378				       s->in2out.addr.as_u32,
379				       s->out2in.addr.as_u32,
380				       s->in2out.protocol,
381				       s->in2out.port,
382				       s->out2in.port, s->in2out.fib_index);
383
384  nat_syslog_nat44_apmadd (s->user_index, s->in2out.fib_index,
385			   &s->in2out.addr, s->in2out.port, &s->out2in.addr,
386			   s->out2in.port, s->in2out.protocol);
387
388  nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
389	       s->out2in.port, &s->ext_host_addr, s->ext_host_port,
390	       &s->ext_host_nat_addr, s->ext_host_nat_port,
391	       s->in2out.protocol, s->in2out.fib_index, s->flags,
392	       thread_index, 0);
393
394  return next0;
395}
396
397#ifndef CLIB_MARCH_VARIANT
398static_always_inline
399  snat_in2out_error_t icmp_get_key (ip4_header_t * ip0,
400				    snat_session_key_t * p_key0)
401{
402  icmp46_header_t *icmp0;
403  snat_session_key_t key0;
404  icmp_echo_header_t *echo0, *inner_echo0 = 0;
405  ip4_header_t *inner_ip0 = 0;
406  void *l4_header = 0;
407  icmp46_header_t *inner_icmp0;
408
409  icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
410  echo0 = (icmp_echo_header_t *) (icmp0 + 1);
411
412  if (!icmp_is_error_message (icmp0))
413    {
414      key0.protocol = SNAT_PROTOCOL_ICMP;
415      key0.addr = ip0->src_address;
416      key0.port = echo0->identifier;
417    }
418  else
419    {
420      inner_ip0 = (ip4_header_t *) (echo0 + 1);
421      l4_header = ip4_next_header (inner_ip0);
422      key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
423      key0.addr = inner_ip0->dst_address;
424      switch (key0.protocol)
425	{
426	case SNAT_PROTOCOL_ICMP:
427	  inner_icmp0 = (icmp46_header_t *) l4_header;
428	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
429	  key0.port = inner_echo0->identifier;
430	  break;
431	case SNAT_PROTOCOL_UDP:
432	case SNAT_PROTOCOL_TCP:
433	  key0.port = ((tcp_udp_header_t *) l4_header)->dst_port;
434	  break;
435	default:
436	  return SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL;
437	}
438    }
439  *p_key0 = key0;
440  return -1;			/* success */
441}
442
443/**
444 * Get address and port values to be used for ICMP packet translation
445 * and create session if needed
446 *
447 * @param[in,out] sm             NAT main
448 * @param[in,out] node           NAT node runtime
449 * @param[in] thread_index       thread index
450 * @param[in,out] b0             buffer containing packet to be translated
451 * @param[out] p_proto           protocol used for matching
452 * @param[out] p_value           address and port after NAT translation
453 * @param[out] p_dont_translate  if packet should not be translated
454 * @param d                      optional parameter
455 * @param e                      optional parameter
456 */
457u32
458icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
459			u32 thread_index, vlib_buffer_t * b0,
460			ip4_header_t * ip0, u8 * p_proto,
461			snat_session_key_t * p_value,
462			u8 * p_dont_translate, void *d, void *e)
463{
464  icmp46_header_t *icmp0;
465  u32 sw_if_index0;
466  u32 rx_fib_index0;
467  snat_session_key_t key0;
468  snat_session_t *s0 = 0;
469  u8 dont_translate = 0;
470  clib_bihash_kv_8_8_t kv0, value0;
471  u32 next0 = ~0;
472  int err;
473
474  icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
475  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
476  rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
477
478  err = icmp_get_key (ip0, &key0);
479  if (err != -1)
480    {
481      b0->error = node->errors[err];
482      next0 = SNAT_IN2OUT_NEXT_DROP;
483      goto out;
484    }
485  key0.fib_index = rx_fib_index0;
486
487  kv0.key = key0.as_u64;
488
489  if (clib_bihash_search_8_8 (&sm->per_thread_data[thread_index].in2out, &kv0,
490			      &value0))
491    {
492      if (vnet_buffer (b0)->sw_if_index[VLIB_TX] != ~0)
493	{
494	  if (PREDICT_FALSE (nat_not_translate_output_feature (sm, ip0,
495							       key0.protocol,
496							       key0.port,
497							       key0.port,
498							       thread_index,
499							       sw_if_index0)))
500	    {
501	      dont_translate = 1;
502	      goto out;
503	    }
504	}
505      else
506	{
507	  if (PREDICT_FALSE (snat_not_translate (sm, node, sw_if_index0,
508						 ip0, SNAT_PROTOCOL_ICMP,
509						 rx_fib_index0,
510						 thread_index)))
511	    {
512	      dont_translate = 1;
513	      goto out;
514	    }
515	}
516
517      if (PREDICT_FALSE (icmp_is_error_message (icmp0)))
518	{
519	  b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
520	  next0 = SNAT_IN2OUT_NEXT_DROP;
521	  goto out;
522	}
523
524      next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0, &s0, node, next0,
525			 thread_index, vlib_time_now (sm->vlib_main));
526
527      if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
528	goto out;
529
530      if (!s0)
531	{
532	  dont_translate = 1;
533	  goto out;
534	}
535    }
536  else
537    {
538      if (PREDICT_FALSE (icmp0->type != ICMP4_echo_request &&
539			 icmp0->type != ICMP4_echo_reply &&
540			 !icmp_is_error_message (icmp0)))
541	{
542	  b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
543	  next0 = SNAT_IN2OUT_NEXT_DROP;
544	  goto out;
545	}
546
547      s0 = pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
548			      value0.value);
549    }
550
551out:
552  *p_proto = key0.protocol;
553  if (s0)
554    *p_value = s0->out2in;
555  *p_dont_translate = dont_translate;
556  if (d)
557    *(snat_session_t **) d = s0;
558  return next0;
559}
560#endif
561
562#ifndef CLIB_MARCH_VARIANT
563/**
564 * Get address and port values to be used for ICMP packet translation
565 *
566 * @param[in] sm                 NAT main
567 * @param[in,out] node           NAT node runtime
568 * @param[in] thread_index       thread index
569 * @param[in,out] b0             buffer containing packet to be translated
570 * @param[out] p_proto           protocol used for matching
571 * @param[out] p_value           address and port after NAT translation
572 * @param[out] p_dont_translate  if packet should not be translated
573 * @param d                      optional parameter
574 * @param e                      optional parameter
575 */
576u32
577icmp_match_in2out_fast (snat_main_t * sm, vlib_node_runtime_t * node,
578			u32 thread_index, vlib_buffer_t * b0,
579			ip4_header_t * ip0, u8 * p_proto,
580			snat_session_key_t * p_value,
581			u8 * p_dont_translate, void *d, void *e)
582{
583  icmp46_header_t *icmp0;
584  u32 sw_if_index0;
585  u32 rx_fib_index0;
586  snat_session_key_t key0;
587  snat_session_key_t sm0;
588  u8 dont_translate = 0;
589  u8 is_addr_only;
590  u32 next0 = ~0;
591  int err;
592
593  icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
594  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
595  rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
596
597  err = icmp_get_key (ip0, &key0);
598  if (err != -1)
599    {
600      b0->error = node->errors[err];
601      next0 = SNAT_IN2OUT_NEXT_DROP;
602      goto out2;
603    }
604  key0.fib_index = rx_fib_index0;
605
606  if (snat_static_mapping_match
607      (sm, key0, &sm0, 0, &is_addr_only, 0, 0, 0, 0))
608    {
609      if (PREDICT_FALSE (snat_not_translate_fast (sm, node, sw_if_index0, ip0,
610						  IP_PROTOCOL_ICMP,
611						  rx_fib_index0)))
612	{
613	  dont_translate = 1;
614	  goto out;
615	}
616
617      if (icmp_is_error_message (icmp0))
618	{
619	  next0 = SNAT_IN2OUT_NEXT_DROP;
620	  goto out;
621	}
622
623      b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
624      next0 = SNAT_IN2OUT_NEXT_DROP;
625      goto out;
626    }
627
628  if (PREDICT_FALSE (icmp0->type != ICMP4_echo_request &&
629		     (icmp0->type != ICMP4_echo_reply || !is_addr_only) &&
630		     !icmp_is_error_message (icmp0)))
631    {
632      b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
633      next0 = SNAT_IN2OUT_NEXT_DROP;
634      goto out;
635    }
636
637out:
638  *p_value = sm0;
639out2:
640  *p_proto = key0.protocol;
641  *p_dont_translate = dont_translate;
642  return next0;
643}
644#endif
645
646#ifndef CLIB_MARCH_VARIANT
647u32
648icmp_in2out (snat_main_t * sm,
649	     vlib_buffer_t * b0,
650	     ip4_header_t * ip0,
651	     icmp46_header_t * icmp0,
652	     u32 sw_if_index0,
653	     u32 rx_fib_index0,
654	     vlib_node_runtime_t * node,
655	     u32 next0, u32 thread_index, void *d, void *e)
656{
657  snat_session_key_t sm0;
658  u8 protocol;
659  icmp_echo_header_t *echo0, *inner_echo0 = 0;
660  ip4_header_t *inner_ip0;
661  void *l4_header = 0;
662  icmp46_header_t *inner_icmp0;
663  u8 dont_translate;
664  u32 new_addr0, old_addr0;
665  u16 old_id0, new_id0;
666  u16 old_checksum0, new_checksum0;
667  ip_csum_t sum0;
668  u16 checksum0;
669  u32 next0_tmp;
670
671  echo0 = (icmp_echo_header_t *) (icmp0 + 1);
672
673  next0_tmp = sm->icmp_match_in2out_cb (sm, node, thread_index, b0, ip0,
674					&protocol, &sm0, &dont_translate, d,
675					e);
676  if (next0_tmp != ~0)
677    next0 = next0_tmp;
678  if (next0 == SNAT_IN2OUT_NEXT_DROP || dont_translate)
679    goto out;
680
681  if (PREDICT_TRUE (!ip4_is_fragment (ip0)))
682    {
683      sum0 = ip_incremental_checksum_buffer (sm->vlib_main, b0, (u8 *) icmp0 -
684					     (u8 *)
685					     vlib_buffer_get_current (b0),
686					     ntohs (ip0->length) -
687					     ip4_header_bytes (ip0), 0);
688      checksum0 = ~ip_csum_fold (sum0);
689      if (PREDICT_FALSE (checksum0 != 0 && checksum0 != 0xffff))
690	{
691	  next0 = SNAT_IN2OUT_NEXT_DROP;
692	  goto out;
693	}
694    }
695
696  old_addr0 = ip0->src_address.as_u32;
697  new_addr0 = ip0->src_address.as_u32 = sm0.addr.as_u32;
698
699  sum0 = ip0->checksum;
700  sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
701			 src_address /* changed member */ );
702  ip0->checksum = ip_csum_fold (sum0);
703
704  if (icmp0->checksum == 0)
705    icmp0->checksum = 0xffff;
706
707  if (!icmp_is_error_message (icmp0))
708    {
709      new_id0 = sm0.port;
710      if (PREDICT_FALSE (new_id0 != echo0->identifier))
711	{
712	  old_id0 = echo0->identifier;
713	  new_id0 = sm0.port;
714	  echo0->identifier = new_id0;
715
716	  sum0 = icmp0->checksum;
717	  sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
718				 identifier);
719	  icmp0->checksum = ip_csum_fold (sum0);
720	}
721    }
722  else
723    {
724      inner_ip0 = (ip4_header_t *) (echo0 + 1);
725      l4_header = ip4_next_header (inner_ip0);
726
727      if (!ip4_header_checksum_is_valid (inner_ip0))
728	{
729	  next0 = SNAT_IN2OUT_NEXT_DROP;
730	  goto out;
731	}
732
733      /* update inner destination IP address */
734      old_addr0 = inner_ip0->dst_address.as_u32;
735      inner_ip0->dst_address = sm0.addr;
736      new_addr0 = inner_ip0->dst_address.as_u32;
737      sum0 = icmp0->checksum;
738      sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
739			     dst_address /* changed member */ );
740      icmp0->checksum = ip_csum_fold (sum0);
741
742      /* update inner IP header checksum */
743      old_checksum0 = inner_ip0->checksum;
744      sum0 = inner_ip0->checksum;
745      sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
746			     dst_address /* changed member */ );
747      inner_ip0->checksum = ip_csum_fold (sum0);
748      new_checksum0 = inner_ip0->checksum;
749      sum0 = icmp0->checksum;
750      sum0 = ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t,
751			     checksum);
752      icmp0->checksum = ip_csum_fold (sum0);
753
754      switch (protocol)
755	{
756	case SNAT_PROTOCOL_ICMP:
757	  inner_icmp0 = (icmp46_header_t *) l4_header;
758	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
759
760	  old_id0 = inner_echo0->identifier;
761	  new_id0 = sm0.port;
762	  inner_echo0->identifier = new_id0;
763
764	  sum0 = icmp0->checksum;
765	  sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t,
766				 identifier);
767	  icmp0->checksum = ip_csum_fold (sum0);
768	  break;
769	case SNAT_PROTOCOL_UDP:
770	case SNAT_PROTOCOL_TCP:
771	  old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port;
772	  new_id0 = sm0.port;
773	  ((tcp_udp_header_t *) l4_header)->dst_port = new_id0;
774
775	  sum0 = icmp0->checksum;
776	  sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t,
777				 dst_port);
778	  icmp0->checksum = ip_csum_fold (sum0);
779	  break;
780	default:
781	  ASSERT (0);
782	}
783    }
784
785  if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0)
786    {
787      if (sm->deterministic ||
788	  0 != snat_icmp_hairpinning (sm, b0, ip0, icmp0,
789				      sm->endpoint_dependent))
790	vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
791    }
792
793out:
794  return next0;
795}
796#endif
797
798static inline u32
799icmp_in2out_slow_path (snat_main_t * sm,
800		       vlib_buffer_t * b0,
801		       ip4_header_t * ip0,
802		       icmp46_header_t * icmp0,
803		       u32 sw_if_index0,
804		       u32 rx_fib_index0,
805		       vlib_node_runtime_t * node,
806		       u32 next0,
807		       f64 now, u32 thread_index, snat_session_t ** p_s0)
808{
809  next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
810		       next0, thread_index, p_s0, 0);
811  snat_session_t *s0 = *p_s0;
812  if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP && s0))
813    {
814      /* Accounting */
815      nat44_session_update_counters (s0, now,
816				     vlib_buffer_length_in_chain
817				     (sm->vlib_main, b0), thread_index);
818      /* Per-user LRU list maintenance */
819      nat44_session_update_lru (sm, s0, thread_index);
820    }
821  return next0;
822}
823
824static int
825nat_in2out_sm_unknown_proto (snat_main_t * sm,
826			     vlib_buffer_t * b,
827			     ip4_header_t * ip, u32 rx_fib_index)
828{
829  clib_bihash_kv_8_8_t kv, value;
830  snat_static_mapping_t *m;
831  snat_session_key_t m_key;
832  u32 old_addr, new_addr;
833  ip_csum_t sum;
834
835  m_key.addr = ip->src_address;
836  m_key.port = 0;
837  m_key.protocol = 0;
838  m_key.fib_index = rx_fib_index;
839  kv.key = m_key.as_u64;
840  if (clib_bihash_search_8_8 (&sm->static_mapping_by_local, &kv, &value))
841    return 1;
842
843  m = pool_elt_at_index (sm->static_mappings, value.value);
844
845  old_addr = ip->src_address.as_u32;
846  new_addr = ip->src_address.as_u32 = m->external_addr.as_u32;
847  sum = ip->checksum;
848  sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, src_address);
849  ip->checksum = ip_csum_fold (sum);
850
851
852  /* Hairpinning */
853  if (vnet_buffer (b)->sw_if_index[VLIB_TX] == ~0)
854    {
855      vnet_buffer (b)->sw_if_index[VLIB_TX] = m->fib_index;
856      nat_hairpinning_sm_unknown_proto (sm, b, ip);
857    }
858
859  return 0;
860}
861
862static inline uword
863snat_in2out_node_fn_inline (vlib_main_t * vm,
864			    vlib_node_runtime_t * node,
865			    vlib_frame_t * frame, int is_slow_path,
866			    int is_output_feature)
867{
868  u32 n_left_from, *from, *to_next;
869  snat_in2out_next_t next_index;
870  u32 pkts_processed = 0;
871  snat_main_t *sm = &snat_main;
872  f64 now = vlib_time_now (vm);
873  u32 stats_node_index;
874  u32 thread_index = vm->thread_index;
875  u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
876    0, fragments = 0;
877
878  stats_node_index = is_slow_path ? sm->in2out_slowpath_node_index :
879    sm->in2out_node_index;
880
881  from = vlib_frame_vector_args (frame);
882  n_left_from = frame->n_vectors;
883  next_index = node->cached_next_index;
884
885  while (n_left_from > 0)
886    {
887      u32 n_left_to_next;
888
889      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
890
891      while (n_left_from >= 4 && n_left_to_next >= 2)
892	{
893	  u32 bi0, bi1;
894	  vlib_buffer_t *b0, *b1;
895	  u32 next0, next1;
896	  u32 sw_if_index0, sw_if_index1;
897	  ip4_header_t *ip0, *ip1;
898	  ip_csum_t sum0, sum1;
899	  u32 new_addr0, old_addr0, new_addr1, old_addr1;
900	  u16 old_port0, new_port0, old_port1, new_port1;
901	  udp_header_t *udp0, *udp1;
902	  tcp_header_t *tcp0, *tcp1;
903	  icmp46_header_t *icmp0, *icmp1;
904	  snat_session_key_t key0, key1;
905	  u32 rx_fib_index0, rx_fib_index1;
906	  u32 proto0, proto1;
907	  snat_session_t *s0 = 0, *s1 = 0;
908	  clib_bihash_kv_8_8_t kv0, value0, kv1, value1;
909	  u32 iph_offset0 = 0, iph_offset1 = 0;
910
911	  /* Prefetch next iteration. */
912	  {
913	    vlib_buffer_t *p2, *p3;
914
915	    p2 = vlib_get_buffer (vm, from[2]);
916	    p3 = vlib_get_buffer (vm, from[3]);
917
918	    vlib_prefetch_buffer_header (p2, LOAD);
919	    vlib_prefetch_buffer_header (p3, LOAD);
920
921	    CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
922	    CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
923	  }
924
925	  /* speculatively enqueue b0 and b1 to the current next frame */
926	  to_next[0] = bi0 = from[0];
927	  to_next[1] = bi1 = from[1];
928	  from += 2;
929	  to_next += 2;
930	  n_left_from -= 2;
931	  n_left_to_next -= 2;
932
933	  b0 = vlib_get_buffer (vm, bi0);
934	  b1 = vlib_get_buffer (vm, bi1);
935
936	  if (is_output_feature)
937	    iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
938
939	  ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
940				  iph_offset0);
941
942	  udp0 = ip4_next_header (ip0);
943	  tcp0 = (tcp_header_t *) udp0;
944	  icmp0 = (icmp46_header_t *) udp0;
945
946	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
947	  rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
948				   sw_if_index0);
949
950	  next0 = next1 = SNAT_IN2OUT_NEXT_LOOKUP;
951
952	  if (PREDICT_FALSE (ip0->ttl == 1))
953	    {
954	      vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
955	      icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
956					   ICMP4_time_exceeded_ttl_exceeded_in_transit,
957					   0);
958	      next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
959	      goto trace00;
960	    }
961
962	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
963
964	  /* Next configured feature, probably ip4-lookup */
965	  if (is_slow_path)
966	    {
967	      if (PREDICT_FALSE (proto0 == ~0))
968		{
969		  if (nat_in2out_sm_unknown_proto
970		      (sm, b0, ip0, rx_fib_index0))
971		    {
972		      next0 = SNAT_IN2OUT_NEXT_DROP;
973		      b0->error =
974			node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
975		    }
976		  other_packets++;
977		  goto trace00;
978		}
979
980	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
981		{
982		  next0 = icmp_in2out_slow_path
983		    (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
984		     node, next0, now, thread_index, &s0);
985		  icmp_packets++;
986		  goto trace00;
987		}
988	    }
989	  else
990	    {
991	      if (PREDICT_FALSE (proto0 == ~0))
992		{
993		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
994		  goto trace00;
995		}
996
997	      if (ip4_is_fragment (ip0))
998		{
999		  next0 = SNAT_IN2OUT_NEXT_REASS;
1000		  fragments++;
1001		  goto trace00;
1002		}
1003
1004	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1005		{
1006		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1007		  goto trace00;
1008		}
1009	    }
1010
1011	  key0.addr = ip0->src_address;
1012	  key0.port = udp0->src_port;
1013	  key0.protocol = proto0;
1014	  key0.fib_index = rx_fib_index0;
1015
1016	  kv0.key = key0.as_u64;
1017
1018	  if (PREDICT_FALSE
1019	      (clib_bihash_search_8_8
1020	       (&sm->per_thread_data[thread_index].in2out, &kv0,
1021		&value0) != 0))
1022	    {
1023	      if (is_slow_path)
1024		{
1025		  if (is_output_feature)
1026		    {
1027		      if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1028									   ip0,
1029									   proto0,
1030									   udp0->src_port,
1031									   udp0->dst_port,
1032									   thread_index,
1033									   sw_if_index0)))
1034			goto trace00;
1035		    }
1036		  else
1037		    {
1038		      if (PREDICT_FALSE
1039			  (snat_not_translate
1040			   (sm, node, sw_if_index0, ip0, proto0,
1041			    rx_fib_index0, thread_index)))
1042			goto trace00;
1043		    }
1044
1045		  next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1046				     &s0, node, next0, thread_index, now);
1047		  if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1048		    goto trace00;
1049
1050		  if (PREDICT_FALSE (!s0))
1051		    goto trace00;
1052		}
1053	      else
1054		{
1055		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1056		  goto trace00;
1057		}
1058	    }
1059	  else
1060	    s0 =
1061	      pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1062				 value0.value);
1063
1064	  b0->flags |= VNET_BUFFER_F_IS_NATED;
1065
1066	  old_addr0 = ip0->src_address.as_u32;
1067	  ip0->src_address = s0->out2in.addr;
1068	  new_addr0 = ip0->src_address.as_u32;
1069	  if (!is_output_feature)
1070	    vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1071
1072	  sum0 = ip0->checksum;
1073	  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1074				 ip4_header_t,
1075				 src_address /* changed member */ );
1076	  ip0->checksum = ip_csum_fold (sum0);
1077
1078	  old_port0 = udp0->src_port;
1079	  new_port0 = udp0->src_port = s0->out2in.port;
1080
1081	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1082	    {
1083	      sum0 = tcp0->checksum;
1084	      sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1085				     ip4_header_t,
1086				     dst_address /* changed member */ );
1087	      sum0 = ip_csum_update (sum0, old_port0, new_port0,
1088				     ip4_header_t /* cheat */ ,
1089				     length /* changed member */ );
1090	      mss_clamping (sm, tcp0, &sum0);
1091	      tcp0->checksum = ip_csum_fold (sum0);
1092	      tcp_packets++;
1093	    }
1094	  else
1095	    {
1096	      if (PREDICT_FALSE (udp0->checksum))
1097		{
1098		  sum0 = udp0->checksum;
1099		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1100					 ip4_header_t,
1101					 dst_address /* changed member */ );
1102		  sum0 = ip_csum_update (sum0, old_port0, new_port0,
1103					 ip4_header_t /* cheat */ ,
1104					 length /* changed member */ );
1105		  udp0->checksum = ip_csum_fold (sum0);
1106		}
1107	      udp_packets++;
1108	    }
1109
1110	  /* Accounting */
1111	  nat44_session_update_counters (s0, now,
1112					 vlib_buffer_length_in_chain (vm, b0),
1113					 thread_index);
1114	  /* Per-user LRU list maintenance */
1115	  nat44_session_update_lru (sm, s0, thread_index);
1116	trace00:
1117
1118	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1119			     && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1120	    {
1121	      snat_in2out_trace_t *t =
1122		vlib_add_trace (vm, node, b0, sizeof (*t));
1123	      t->is_slow_path = is_slow_path;
1124	      t->sw_if_index = sw_if_index0;
1125	      t->next_index = next0;
1126	      t->session_index = ~0;
1127	      if (s0)
1128		t->session_index =
1129		  s0 - sm->per_thread_data[thread_index].sessions;
1130	    }
1131
1132	  pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1133
1134	  if (is_output_feature)
1135	    iph_offset1 = vnet_buffer (b1)->ip.save_rewrite_length;
1136
1137	  ip1 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b1) +
1138				  iph_offset1);
1139
1140	  udp1 = ip4_next_header (ip1);
1141	  tcp1 = (tcp_header_t *) udp1;
1142	  icmp1 = (icmp46_header_t *) udp1;
1143
1144	  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
1145	  rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1146				   sw_if_index1);
1147
1148	  if (PREDICT_FALSE (ip1->ttl == 1))
1149	    {
1150	      vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1151	      icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1152					   ICMP4_time_exceeded_ttl_exceeded_in_transit,
1153					   0);
1154	      next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1155	      goto trace01;
1156	    }
1157
1158	  proto1 = ip_proto_to_snat_proto (ip1->protocol);
1159
1160	  /* Next configured feature, probably ip4-lookup */
1161	  if (is_slow_path)
1162	    {
1163	      if (PREDICT_FALSE (proto1 == ~0))
1164		{
1165		  if (nat_in2out_sm_unknown_proto
1166		      (sm, b1, ip1, rx_fib_index1))
1167		    {
1168		      next1 = SNAT_IN2OUT_NEXT_DROP;
1169		      b1->error =
1170			node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1171		    }
1172		  other_packets++;
1173		  goto trace01;
1174		}
1175
1176	      if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1177		{
1178		  next1 = icmp_in2out_slow_path
1179		    (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1180		     next1, now, thread_index, &s1);
1181		  icmp_packets++;
1182		  goto trace01;
1183		}
1184	    }
1185	  else
1186	    {
1187	      if (PREDICT_FALSE (proto1 == ~0))
1188		{
1189		  next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1190		  goto trace01;
1191		}
1192
1193	      if (ip4_is_fragment (ip1))
1194		{
1195		  next1 = SNAT_IN2OUT_NEXT_REASS;
1196		  fragments++;
1197		  goto trace01;
1198		}
1199
1200	      if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1201		{
1202		  next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1203		  goto trace01;
1204		}
1205	    }
1206
1207	  key1.addr = ip1->src_address;
1208	  key1.port = udp1->src_port;
1209	  key1.protocol = proto1;
1210	  key1.fib_index = rx_fib_index1;
1211
1212	  kv1.key = key1.as_u64;
1213
1214	  if (PREDICT_FALSE
1215	      (clib_bihash_search_8_8
1216	       (&sm->per_thread_data[thread_index].in2out, &kv1,
1217		&value1) != 0))
1218	    {
1219	      if (is_slow_path)
1220		{
1221		  if (is_output_feature)
1222		    {
1223		      if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1224									   ip1,
1225									   proto1,
1226									   udp1->src_port,
1227									   udp1->dst_port,
1228									   thread_index,
1229									   sw_if_index1)))
1230			goto trace01;
1231		    }
1232		  else
1233		    {
1234		      if (PREDICT_FALSE
1235			  (snat_not_translate
1236			   (sm, node, sw_if_index1, ip1, proto1,
1237			    rx_fib_index1, thread_index)))
1238			goto trace01;
1239		    }
1240
1241		  next1 = slow_path (sm, b1, ip1, rx_fib_index1, &key1,
1242				     &s1, node, next1, thread_index, now);
1243		  if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP))
1244		    goto trace01;
1245
1246		  if (PREDICT_FALSE (!s1))
1247		    goto trace01;
1248		}
1249	      else
1250		{
1251		  next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1252		  goto trace01;
1253		}
1254	    }
1255	  else
1256	    s1 =
1257	      pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1258				 value1.value);
1259
1260	  b1->flags |= VNET_BUFFER_F_IS_NATED;
1261
1262	  old_addr1 = ip1->src_address.as_u32;
1263	  ip1->src_address = s1->out2in.addr;
1264	  new_addr1 = ip1->src_address.as_u32;
1265	  if (!is_output_feature)
1266	    vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->out2in.fib_index;
1267
1268	  sum1 = ip1->checksum;
1269	  sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1270				 ip4_header_t,
1271				 src_address /* changed member */ );
1272	  ip1->checksum = ip_csum_fold (sum1);
1273
1274	  old_port1 = udp1->src_port;
1275	  new_port1 = udp1->src_port = s1->out2in.port;
1276
1277	  if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
1278	    {
1279	      sum1 = tcp1->checksum;
1280	      sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1281				     ip4_header_t,
1282				     dst_address /* changed member */ );
1283	      sum1 = ip_csum_update (sum1, old_port1, new_port1,
1284				     ip4_header_t /* cheat */ ,
1285				     length /* changed member */ );
1286	      mss_clamping (sm, tcp1, &sum1);
1287	      tcp1->checksum = ip_csum_fold (sum1);
1288	      tcp_packets++;
1289	    }
1290	  else
1291	    {
1292	      if (PREDICT_FALSE (udp1->checksum))
1293		{
1294		  sum1 = udp1->checksum;
1295		  sum1 = ip_csum_update (sum1, old_addr1, new_addr1,
1296					 ip4_header_t,
1297					 dst_address /* changed member */ );
1298		  sum1 = ip_csum_update (sum1, old_port1, new_port1,
1299					 ip4_header_t /* cheat */ ,
1300					 length /* changed member */ );
1301		  udp1->checksum = ip_csum_fold (sum1);
1302		}
1303	      udp_packets++;
1304	    }
1305
1306	  /* Accounting */
1307	  nat44_session_update_counters (s1, now,
1308					 vlib_buffer_length_in_chain (vm, b1),
1309					 thread_index);
1310	  /* Per-user LRU list maintenance */
1311	  nat44_session_update_lru (sm, s1, thread_index);
1312	trace01:
1313
1314	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1315			     && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1316	    {
1317	      snat_in2out_trace_t *t =
1318		vlib_add_trace (vm, node, b1, sizeof (*t));
1319	      t->sw_if_index = sw_if_index1;
1320	      t->next_index = next1;
1321	      t->session_index = ~0;
1322	      if (s1)
1323		t->session_index =
1324		  s1 - sm->per_thread_data[thread_index].sessions;
1325	    }
1326
1327	  pkts_processed += next1 == SNAT_IN2OUT_NEXT_LOOKUP;
1328
1329	  /* verify speculative enqueues, maybe switch current next frame */
1330	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1331					   to_next, n_left_to_next,
1332					   bi0, bi1, next0, next1);
1333	}
1334
1335      while (n_left_from > 0 && n_left_to_next > 0)
1336	{
1337	  u32 bi0;
1338	  vlib_buffer_t *b0;
1339	  u32 next0;
1340	  u32 sw_if_index0;
1341	  ip4_header_t *ip0;
1342	  ip_csum_t sum0;
1343	  u32 new_addr0, old_addr0;
1344	  u16 old_port0, new_port0;
1345	  udp_header_t *udp0;
1346	  tcp_header_t *tcp0;
1347	  icmp46_header_t *icmp0;
1348	  snat_session_key_t key0;
1349	  u32 rx_fib_index0;
1350	  u32 proto0;
1351	  snat_session_t *s0 = 0;
1352	  clib_bihash_kv_8_8_t kv0, value0;
1353	  u32 iph_offset0 = 0;
1354
1355	  /* speculatively enqueue b0 to the current next frame */
1356	  bi0 = from[0];
1357	  to_next[0] = bi0;
1358	  from += 1;
1359	  to_next += 1;
1360	  n_left_from -= 1;
1361	  n_left_to_next -= 1;
1362
1363	  b0 = vlib_get_buffer (vm, bi0);
1364	  next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1365
1366	  if (is_output_feature)
1367	    iph_offset0 = vnet_buffer (b0)->ip.save_rewrite_length;
1368
1369	  ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) +
1370				  iph_offset0);
1371
1372	  udp0 = ip4_next_header (ip0);
1373	  tcp0 = (tcp_header_t *) udp0;
1374	  icmp0 = (icmp46_header_t *) udp0;
1375
1376	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1377	  rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
1378				   sw_if_index0);
1379
1380	  if (PREDICT_FALSE (ip0->ttl == 1))
1381	    {
1382	      vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1383	      icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1384					   ICMP4_time_exceeded_ttl_exceeded_in_transit,
1385					   0);
1386	      next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
1387	      goto trace0;
1388	    }
1389
1390	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
1391
1392	  /* Next configured feature, probably ip4-lookup */
1393	  if (is_slow_path)
1394	    {
1395	      if (PREDICT_FALSE (proto0 == ~0))
1396		{
1397		  if (nat_in2out_sm_unknown_proto
1398		      (sm, b0, ip0, rx_fib_index0))
1399		    {
1400		      next0 = SNAT_IN2OUT_NEXT_DROP;
1401		      b0->error =
1402			node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
1403		    }
1404		  other_packets++;
1405		  goto trace0;
1406		}
1407
1408	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1409		{
1410		  next0 = icmp_in2out_slow_path
1411		    (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1412		     next0, now, thread_index, &s0);
1413		  icmp_packets++;
1414		  goto trace0;
1415		}
1416	    }
1417	  else
1418	    {
1419	      if (PREDICT_FALSE (proto0 == ~0))
1420		{
1421		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1422		  goto trace0;
1423		}
1424
1425	      if (ip4_is_fragment (ip0))
1426		{
1427		  next0 = SNAT_IN2OUT_NEXT_REASS;
1428		  fragments++;
1429		  goto trace0;
1430		}
1431
1432	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1433		{
1434		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1435		  goto trace0;
1436		}
1437	    }
1438
1439	  key0.addr = ip0->src_address;
1440	  key0.port = udp0->src_port;
1441	  key0.protocol = proto0;
1442	  key0.fib_index = rx_fib_index0;
1443
1444	  kv0.key = key0.as_u64;
1445
1446	  if (clib_bihash_search_8_8
1447	      (&sm->per_thread_data[thread_index].in2out, &kv0, &value0))
1448	    {
1449	      if (is_slow_path)
1450		{
1451		  if (is_output_feature)
1452		    {
1453		      if (PREDICT_FALSE (nat_not_translate_output_feature (sm,
1454									   ip0,
1455									   proto0,
1456									   udp0->src_port,
1457									   udp0->dst_port,
1458									   thread_index,
1459									   sw_if_index0)))
1460			goto trace0;
1461		    }
1462		  else
1463		    {
1464		      if (PREDICT_FALSE
1465			  (snat_not_translate
1466			   (sm, node, sw_if_index0, ip0, proto0,
1467			    rx_fib_index0, thread_index)))
1468			goto trace0;
1469		    }
1470
1471		  next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1472				     &s0, node, next0, thread_index, now);
1473
1474		  if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1475		    goto trace0;
1476
1477		  if (PREDICT_FALSE (!s0))
1478		    goto trace0;
1479		}
1480	      else
1481		{
1482		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
1483		  goto trace0;
1484		}
1485	    }
1486	  else
1487	    s0 =
1488	      pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
1489				 value0.value);
1490
1491	  b0->flags |= VNET_BUFFER_F_IS_NATED;
1492
1493	  old_addr0 = ip0->src_address.as_u32;
1494	  ip0->src_address = s0->out2in.addr;
1495	  new_addr0 = ip0->src_address.as_u32;
1496	  if (!is_output_feature)
1497	    vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1498
1499	  sum0 = ip0->checksum;
1500	  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1501				 ip4_header_t,
1502				 src_address /* changed member */ );
1503	  ip0->checksum = ip_csum_fold (sum0);
1504
1505	  old_port0 = udp0->src_port;
1506	  new_port0 = udp0->src_port = s0->out2in.port;
1507
1508	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1509	    {
1510	      sum0 = tcp0->checksum;
1511	      sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1512				     ip4_header_t,
1513				     dst_address /* changed member */ );
1514	      sum0 = ip_csum_update (sum0, old_port0, new_port0,
1515				     ip4_header_t /* cheat */ ,
1516				     length /* changed member */ );
1517	      mss_clamping (sm, tcp0, &sum0);
1518	      tcp0->checksum = ip_csum_fold (sum0);
1519	      tcp_packets++;
1520	    }
1521	  else
1522	    {
1523	      if (PREDICT_FALSE (udp0->checksum))
1524		{
1525		  sum0 = udp0->checksum;
1526		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1527					 ip4_header_t,
1528					 dst_address /* changed member */ );
1529		  sum0 = ip_csum_update (sum0, old_port0, new_port0,
1530					 ip4_header_t /* cheat */ ,
1531					 length /* changed member */ );
1532		  udp0->checksum = ip_csum_fold (sum0);
1533		}
1534	      udp_packets++;
1535	    }
1536
1537	  /* Accounting */
1538	  nat44_session_update_counters (s0, now,
1539					 vlib_buffer_length_in_chain (vm, b0),
1540					 thread_index);
1541	  /* Per-user LRU list maintenance */
1542	  nat44_session_update_lru (sm, s0, thread_index);
1543
1544	trace0:
1545	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1546			     && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1547	    {
1548	      snat_in2out_trace_t *t =
1549		vlib_add_trace (vm, node, b0, sizeof (*t));
1550	      t->is_slow_path = is_slow_path;
1551	      t->sw_if_index = sw_if_index0;
1552	      t->next_index = next0;
1553	      t->session_index = ~0;
1554	      if (s0)
1555		t->session_index =
1556		  s0 - sm->per_thread_data[thread_index].sessions;
1557	    }
1558
1559	  pkts_processed += next0 == SNAT_IN2OUT_NEXT_LOOKUP;
1560
1561	  /* verify speculative enqueue, maybe switch current next frame */
1562	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1563					   to_next, n_left_to_next,
1564					   bi0, next0);
1565	}
1566
1567      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1568    }
1569
1570  vlib_node_increment_counter (vm, stats_node_index,
1571			       SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
1572			       pkts_processed);
1573  vlib_node_increment_counter (vm, stats_node_index,
1574			       SNAT_IN2OUT_ERROR_TCP_PACKETS, tcp_packets);
1575  vlib_node_increment_counter (vm, stats_node_index,
1576			       SNAT_IN2OUT_ERROR_UDP_PACKETS, tcp_packets);
1577  vlib_node_increment_counter (vm, stats_node_index,
1578			       SNAT_IN2OUT_ERROR_ICMP_PACKETS, icmp_packets);
1579  vlib_node_increment_counter (vm, stats_node_index,
1580			       SNAT_IN2OUT_ERROR_OTHER_PACKETS,
1581			       other_packets);
1582  vlib_node_increment_counter (vm, stats_node_index,
1583			       SNAT_IN2OUT_ERROR_FRAGMENTS, fragments);
1584
1585  return frame->n_vectors;
1586}
1587
1588VLIB_NODE_FN (snat_in2out_node) (vlib_main_t * vm,
1589				 vlib_node_runtime_t * node,
1590				 vlib_frame_t * frame)
1591{
1592  return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1593				     0);
1594}
1595
1596/* *INDENT-OFF* */
1597VLIB_REGISTER_NODE (snat_in2out_node) = {
1598  .name = "nat44-in2out",
1599  .vector_size = sizeof (u32),
1600  .format_trace = format_snat_in2out_trace,
1601  .type = VLIB_NODE_TYPE_INTERNAL,
1602
1603  .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1604  .error_strings = snat_in2out_error_strings,
1605
1606  .runtime_data_bytes = sizeof (snat_runtime_t),
1607
1608  .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1609
1610  /* edit / add dispositions here */
1611  .next_nodes = {
1612    [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1613    [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1614    [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1615    [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1616    [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1617  },
1618};
1619/* *INDENT-ON* */
1620
1621VLIB_NODE_FN (snat_in2out_output_node) (vlib_main_t * vm,
1622					vlib_node_runtime_t * node,
1623					vlib_frame_t * frame)
1624{
1625  return snat_in2out_node_fn_inline (vm, node, frame, 0 /* is_slow_path */ ,
1626				     1);
1627}
1628
1629/* *INDENT-OFF* */
1630VLIB_REGISTER_NODE (snat_in2out_output_node) = {
1631  .name = "nat44-in2out-output",
1632  .vector_size = sizeof (u32),
1633  .format_trace = format_snat_in2out_trace,
1634  .type = VLIB_NODE_TYPE_INTERNAL,
1635
1636  .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1637  .error_strings = snat_in2out_error_strings,
1638
1639  .runtime_data_bytes = sizeof (snat_runtime_t),
1640
1641  .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1642
1643  /* edit / add dispositions here */
1644  .next_nodes = {
1645    [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1646    [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1647    [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1648    [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1649    [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1650  },
1651};
1652/* *INDENT-ON* */
1653
1654VLIB_NODE_FN (snat_in2out_slowpath_node) (vlib_main_t * vm,
1655					  vlib_node_runtime_t * node,
1656					  vlib_frame_t * frame)
1657{
1658  return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1659				     0);
1660}
1661
1662/* *INDENT-OFF* */
1663VLIB_REGISTER_NODE (snat_in2out_slowpath_node) = {
1664  .name = "nat44-in2out-slowpath",
1665  .vector_size = sizeof (u32),
1666  .format_trace = format_snat_in2out_trace,
1667  .type = VLIB_NODE_TYPE_INTERNAL,
1668
1669  .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1670  .error_strings = snat_in2out_error_strings,
1671
1672  .runtime_data_bytes = sizeof (snat_runtime_t),
1673
1674  .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1675
1676  /* edit / add dispositions here */
1677  .next_nodes = {
1678    [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1679    [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
1680    [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
1681    [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1682    [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1683  },
1684};
1685/* *INDENT-ON* */
1686
1687VLIB_NODE_FN (snat_in2out_output_slowpath_node) (vlib_main_t * vm,
1688						 vlib_node_runtime_t * node,
1689						 vlib_frame_t * frame)
1690{
1691  return snat_in2out_node_fn_inline (vm, node, frame, 1 /* is_slow_path */ ,
1692				     1);
1693}
1694
1695/* *INDENT-OFF* */
1696VLIB_REGISTER_NODE (snat_in2out_output_slowpath_node) = {
1697  .name = "nat44-in2out-output-slowpath",
1698  .vector_size = sizeof (u32),
1699  .format_trace = format_snat_in2out_trace,
1700  .type = VLIB_NODE_TYPE_INTERNAL,
1701
1702  .n_errors = ARRAY_LEN(snat_in2out_error_strings),
1703  .error_strings = snat_in2out_error_strings,
1704
1705  .runtime_data_bytes = sizeof (snat_runtime_t),
1706
1707  .n_next_nodes = SNAT_IN2OUT_N_NEXT,
1708
1709  /* edit / add dispositions here */
1710  .next_nodes = {
1711    [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
1712    [SNAT_IN2OUT_NEXT_LOOKUP] = "interface-output",
1713    [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-output-slowpath",
1714    [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
1715    [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
1716  },
1717};
1718/* *INDENT-ON* */
1719
1720VLIB_NODE_FN (nat44_in2out_reass_node) (vlib_main_t * vm,
1721					vlib_node_runtime_t * node,
1722					vlib_frame_t * frame)
1723{
1724  u32 n_left_from, *from, *to_next;
1725  snat_in2out_next_t next_index;
1726  u32 pkts_processed = 0, cached_fragments = 0;
1727  snat_main_t *sm = &snat_main;
1728  f64 now = vlib_time_now (vm);
1729  u32 thread_index = vm->thread_index;
1730  snat_main_per_thread_data_t *per_thread_data =
1731    &sm->per_thread_data[thread_index];
1732  u32 *fragments_to_drop = 0;
1733  u32 *fragments_to_loopback = 0;
1734
1735  from = vlib_frame_vector_args (frame);
1736  n_left_from = frame->n_vectors;
1737  next_index = node->cached_next_index;
1738
1739  while (n_left_from > 0)
1740    {
1741      u32 n_left_to_next;
1742
1743      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1744
1745      while (n_left_from > 0 && n_left_to_next > 0)
1746	{
1747	  u32 bi0, sw_if_index0, proto0, rx_fib_index0, new_addr0, old_addr0;
1748	  vlib_buffer_t *b0;
1749	  u32 next0;
1750	  u8 cached0 = 0;
1751	  ip4_header_t *ip0;
1752	  nat_reass_ip4_t *reass0;
1753	  udp_header_t *udp0;
1754	  tcp_header_t *tcp0;
1755	  icmp46_header_t *icmp0;
1756	  snat_session_key_t key0;
1757	  clib_bihash_kv_8_8_t kv0, value0;
1758	  snat_session_t *s0 = 0;
1759	  u16 old_port0, new_port0;
1760	  ip_csum_t sum0;
1761
1762	  /* speculatively enqueue b0 to the current next frame */
1763	  bi0 = from[0];
1764	  to_next[0] = bi0;
1765	  from += 1;
1766	  to_next += 1;
1767	  n_left_from -= 1;
1768	  n_left_to_next -= 1;
1769
1770	  b0 = vlib_get_buffer (vm, bi0);
1771	  next0 = SNAT_IN2OUT_NEXT_LOOKUP;
1772
1773	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1774	  rx_fib_index0 =
1775	    fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1776						 sw_if_index0);
1777
1778	  if (PREDICT_FALSE (nat_reass_is_drop_frag (0)))
1779	    {
1780	      next0 = SNAT_IN2OUT_NEXT_DROP;
1781	      b0->error = node->errors[SNAT_IN2OUT_ERROR_DROP_FRAGMENT];
1782	      goto trace0;
1783	    }
1784
1785	  ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
1786	  udp0 = ip4_next_header (ip0);
1787	  tcp0 = (tcp_header_t *) udp0;
1788	  icmp0 = (icmp46_header_t *) udp0;
1789	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
1790
1791	  reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
1792						 ip0->dst_address,
1793						 ip0->fragment_id,
1794						 ip0->protocol,
1795						 1, &fragments_to_drop);
1796
1797	  if (PREDICT_FALSE (!reass0))
1798	    {
1799	      next0 = SNAT_IN2OUT_NEXT_DROP;
1800	      b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_REASS];
1801	      nat_elog_notice ("maximum reassemblies exceeded");
1802	      goto trace0;
1803	    }
1804
1805	  if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1806	    {
1807	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1808		{
1809		  next0 = icmp_in2out_slow_path
1810		    (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1811		     next0, now, thread_index, &s0);
1812
1813		  if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP))
1814		    {
1815		      if (s0)
1816			reass0->sess_index = s0 - per_thread_data->sessions;
1817		      else
1818			reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1819		      nat_ip4_reass_get_frags (reass0,
1820					       &fragments_to_loopback);
1821		    }
1822
1823		  goto trace0;
1824		}
1825
1826	      key0.addr = ip0->src_address;
1827	      key0.port = udp0->src_port;
1828	      key0.protocol = proto0;
1829	      key0.fib_index = rx_fib_index0;
1830	      kv0.key = key0.as_u64;
1831
1832	      if (clib_bihash_search_8_8
1833		  (&per_thread_data->in2out, &kv0, &value0))
1834		{
1835		  if (PREDICT_FALSE
1836		      (snat_not_translate
1837		       (sm, node, sw_if_index0, ip0, proto0, rx_fib_index0,
1838			thread_index)))
1839		    goto trace0;
1840
1841		  next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0,
1842				     &s0, node, next0, thread_index, now);
1843
1844		  if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP))
1845		    goto trace0;
1846
1847		  if (PREDICT_FALSE (!s0))
1848		    goto trace0;
1849
1850		  reass0->sess_index = s0 - per_thread_data->sessions;
1851		}
1852	      else
1853		{
1854		  s0 = pool_elt_at_index (per_thread_data->sessions,
1855					  value0.value);
1856		  reass0->sess_index = value0.value;
1857		}
1858	      nat_ip4_reass_get_frags (reass0, &fragments_to_loopback);
1859	    }
1860	  else
1861	    {
1862	      if (PREDICT_FALSE (reass0->sess_index == (u32) ~ 0))
1863		{
1864		  if (nat_ip4_reass_add_fragment
1865		      (thread_index, reass0, bi0, &fragments_to_drop))
1866		    {
1867		      b0->error = node->errors[SNAT_IN2OUT_ERROR_MAX_FRAG];
1868		      nat_elog_notice
1869			("maximum fragments per reassembly exceeded");
1870		      next0 = SNAT_IN2OUT_NEXT_DROP;
1871		      goto trace0;
1872		    }
1873		  cached0 = 1;
1874		  goto trace0;
1875		}
1876	      s0 = pool_elt_at_index (per_thread_data->sessions,
1877				      reass0->sess_index);
1878	    }
1879
1880	  old_addr0 = ip0->src_address.as_u32;
1881	  ip0->src_address = s0->out2in.addr;
1882	  new_addr0 = ip0->src_address.as_u32;
1883	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->out2in.fib_index;
1884
1885	  sum0 = ip0->checksum;
1886	  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1887				 ip4_header_t,
1888				 src_address /* changed member */ );
1889	  ip0->checksum = ip_csum_fold (sum0);
1890
1891	  if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1892	    {
1893	      old_port0 = udp0->src_port;
1894	      new_port0 = udp0->src_port = s0->out2in.port;
1895
1896	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1897		{
1898		  sum0 = tcp0->checksum;
1899		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1900					 ip4_header_t,
1901					 dst_address /* changed member */ );
1902		  sum0 = ip_csum_update (sum0, old_port0, new_port0,
1903					 ip4_header_t /* cheat */ ,
1904					 length /* changed member */ );
1905		  tcp0->checksum = ip_csum_fold (sum0);
1906		}
1907	      else if (PREDICT_FALSE (udp0->checksum))
1908		{
1909		  sum0 = udp0->checksum;
1910		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1911					 ip4_header_t,
1912					 dst_address /* changed member */ );
1913		  sum0 = ip_csum_update (sum0, old_port0, new_port0,
1914					 ip4_header_t /* cheat */ ,
1915					 length /* changed member */ );
1916		  udp0->checksum = ip_csum_fold (sum0);
1917		}
1918	    }
1919
1920	  /* Hairpinning */
1921	  nat44_reass_hairpinning (sm, b0, ip0, s0->out2in.port,
1922				   s0->ext_host_port, proto0, 0);
1923
1924	  /* Accounting */
1925	  nat44_session_update_counters (s0, now,
1926					 vlib_buffer_length_in_chain (vm, b0),
1927					 thread_index);
1928	  /* Per-user LRU list maintenance */
1929	  nat44_session_update_lru (sm, s0, thread_index);
1930
1931	trace0:
1932	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1933			     && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1934	    {
1935	      nat44_reass_trace_t *t =
1936		vlib_add_trace (vm, node, b0, sizeof (*t));
1937	      t->cached = cached0;
1938	      t->sw_if_index = sw_if_index0;
1939	      t->next_index = next0;
1940	    }
1941
1942	  if (cached0)
1943	    {
1944	      n_left_to_next++;
1945	      to_next--;
1946	      cached_fragments++;
1947	    }
1948	  else
1949	    {
1950	      pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
1951
1952	      /* verify speculative enqueue, maybe switch current next frame */
1953	      vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1954					       to_next, n_left_to_next,
1955					       bi0, next0);
1956	    }
1957
1958	  if (n_left_from == 0 && vec_len (fragments_to_loopback))
1959	    {
1960	      from = vlib_frame_vector_args (frame);
1961	      u32 len = vec_len (fragments_to_loopback);
1962	      if (len <= VLIB_FRAME_SIZE)
1963		{
1964		  clib_memcpy_fast (from, fragments_to_loopback,
1965				    sizeof (u32) * len);
1966		  n_left_from = len;
1967		  vec_reset_length (fragments_to_loopback);
1968		}
1969	      else
1970		{
1971		  clib_memcpy_fast (from, fragments_to_loopback +
1972				    (len - VLIB_FRAME_SIZE),
1973				    sizeof (u32) * VLIB_FRAME_SIZE);
1974		  n_left_from = VLIB_FRAME_SIZE;
1975		  _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
1976		}
1977	    }
1978	}
1979
1980      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1981    }
1982
1983  vlib_node_increment_counter (vm, sm->in2out_reass_node_index,
1984			       SNAT_IN2OUT_ERROR_PROCESSED_FRAGMENTS,
1985			       pkts_processed);
1986  vlib_node_increment_counter (vm, sm->in2out_reass_node_index,
1987			       SNAT_IN2OUT_ERROR_CACHED_FRAGMENTS,
1988			       cached_fragments);
1989
1990  nat_send_all_to_node (vm, fragments_to_drop, node,
1991			&node->errors[SNAT_IN2OUT_ERROR_DROP_FRAGMENT],
1992			SNAT_IN2OUT_NEXT_DROP);
1993
1994  vec_free (fragments_to_drop);
1995  vec_free (fragments_to_loopback);
1996  return frame->n_vectors;
1997}
1998
1999/* *INDENT-OFF* */
2000VLIB_REGISTER_NODE (nat44_in2out_reass_node) = {
2001  .name = "nat44-in2out-reass",
2002  .vector_size = sizeof (u32),
2003  .format_trace = format_nat44_reass_trace,
2004  .type = VLIB_NODE_TYPE_INTERNAL,
2005
2006  .n_errors = ARRAY_LEN(snat_in2out_error_strings),
2007  .error_strings = snat_in2out_error_strings,
2008
2009  .n_next_nodes = SNAT_IN2OUT_N_NEXT,
2010  .next_nodes = {
2011    [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
2012    [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
2013    [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
2014    [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2015    [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
2016  },
2017};
2018/* *INDENT-ON* */
2019
2020VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
2021				      vlib_node_runtime_t * node,
2022				      vlib_frame_t * frame)
2023{
2024  u32 n_left_from, *from, *to_next;
2025  snat_in2out_next_t next_index;
2026  u32 pkts_processed = 0;
2027  snat_main_t *sm = &snat_main;
2028  u32 stats_node_index;
2029
2030  stats_node_index = sm->in2out_fast_node_index;
2031
2032  from = vlib_frame_vector_args (frame);
2033  n_left_from = frame->n_vectors;
2034  next_index = node->cached_next_index;
2035
2036  while (n_left_from > 0)
2037    {
2038      u32 n_left_to_next;
2039
2040      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2041
2042      while (n_left_from > 0 && n_left_to_next > 0)
2043	{
2044	  u32 bi0;
2045	  vlib_buffer_t *b0;
2046	  u32 next0;
2047	  u32 sw_if_index0;
2048	  ip4_header_t *ip0;
2049	  ip_csum_t sum0;
2050	  u32 new_addr0, old_addr0;
2051	  u16 old_port0, new_port0;
2052	  udp_header_t *udp0;
2053	  tcp_header_t *tcp0;
2054	  icmp46_header_t *icmp0;
2055	  snat_session_key_t key0, sm0;
2056	  u32 proto0;
2057	  u32 rx_fib_index0;
2058
2059	  /* speculatively enqueue b0 to the current next frame */
2060	  bi0 = from[0];
2061	  to_next[0] = bi0;
2062	  from += 1;
2063	  to_next += 1;
2064	  n_left_from -= 1;
2065	  n_left_to_next -= 1;
2066
2067	  b0 = vlib_get_buffer (vm, bi0);
2068	  next0 = SNAT_IN2OUT_NEXT_LOOKUP;
2069
2070	  ip0 = vlib_buffer_get_current (b0);
2071	  udp0 = ip4_next_header (ip0);
2072	  tcp0 = (tcp_header_t *) udp0;
2073	  icmp0 = (icmp46_header_t *) udp0;
2074
2075	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2076	  rx_fib_index0 =
2077	    ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
2078
2079	  if (PREDICT_FALSE (ip0->ttl == 1))
2080	    {
2081	      vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
2082	      icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
2083					   ICMP4_time_exceeded_ttl_exceeded_in_transit,
2084					   0);
2085	      next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
2086	      goto trace0;
2087	    }
2088
2089	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
2090
2091	  if (PREDICT_FALSE (proto0 == ~0))
2092	    goto trace0;
2093
2094	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
2095	    {
2096	      next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
2097				   rx_fib_index0, node, next0, ~0, 0, 0);
2098	      goto trace0;
2099	    }
2100
2101	  key0.addr = ip0->src_address;
2102	  key0.protocol = proto0;
2103	  key0.port = udp0->src_port;
2104	  key0.fib_index = rx_fib_index0;
2105
2106	  if (snat_static_mapping_match (sm, key0, &sm0, 0, 0, 0, 0, 0, 0))
2107	    {
2108	      b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
2109	      next0 = SNAT_IN2OUT_NEXT_DROP;
2110	      goto trace0;
2111	    }
2112
2113	  new_addr0 = sm0.addr.as_u32;
2114	  new_port0 = sm0.port;
2115	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
2116	  old_addr0 = ip0->src_address.as_u32;
2117	  ip0->src_address.as_u32 = new_addr0;
2118
2119	  sum0 = ip0->checksum;
2120	  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2121				 ip4_header_t,
2122				 src_address /* changed member */ );
2123	  ip0->checksum = ip_csum_fold (sum0);
2124
2125	  if (PREDICT_FALSE (new_port0 != udp0->dst_port))
2126	    {
2127	      old_port0 = udp0->src_port;
2128	      udp0->src_port = new_port0;
2129
2130	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
2131		{
2132		  sum0 = tcp0->checksum;
2133		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2134					 ip4_header_t,
2135					 dst_address /* changed member */ );
2136		  sum0 = ip_csum_update (sum0, old_port0, new_port0,
2137					 ip4_header_t /* cheat */ ,
2138					 length /* changed member */ );
2139		  mss_clamping (sm, tcp0, &sum0);
2140		  tcp0->checksum = ip_csum_fold (sum0);
2141		}
2142	      else if (udp0->checksum)
2143		{
2144		  sum0 = udp0->checksum;
2145		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2146					 ip4_header_t,
2147					 dst_address /* changed member */ );
2148		  sum0 = ip_csum_update (sum0, old_port0, new_port0,
2149					 ip4_header_t /* cheat */ ,
2150					 length /* changed member */ );
2151		  udp0->checksum = ip_csum_fold (sum0);
2152		}
2153	    }
2154	  else
2155	    {
2156	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
2157		{
2158		  sum0 = tcp0->checksum;
2159		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2160					 ip4_header_t,
2161					 dst_address /* changed member */ );
2162		  mss_clamping (sm, tcp0, &sum0);
2163		  tcp0->checksum = ip_csum_fold (sum0);
2164		}
2165	      else if (udp0->checksum)
2166		{
2167		  sum0 = udp0->checksum;
2168		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
2169					 ip4_header_t,
2170					 dst_address /* changed member */ );
2171		  udp0->checksum = ip_csum_fold (sum0);
2172		}
2173	    }
2174
2175	  /* Hairpinning */
2176	  snat_hairpinning (sm, b0, ip0, udp0, tcp0, proto0, 0);
2177
2178	trace0:
2179	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
2180			     && (b0->flags & VLIB_BUFFER_IS_TRACED)))
2181	    {
2182	      snat_in2out_trace_t *t =
2183		vlib_add_trace (vm, node, b0, sizeof (*t));
2184	      t->sw_if_index = sw_if_index0;
2185	      t->next_index = next0;
2186	    }
2187
2188	  pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
2189
2190	  /* verify speculative enqueue, maybe switch current next frame */
2191	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
2192					   to_next, n_left_to_next,
2193					   bi0, next0);
2194	}
2195
2196      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2197    }
2198
2199  vlib_node_increment_counter (vm, stats_node_index,
2200			       SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
2201			       pkts_processed);
2202  return frame->n_vectors;
2203}
2204
2205
2206/* *INDENT-OFF* */
2207VLIB_REGISTER_NODE (snat_in2out_fast_node) = {
2208  .name = "nat44-in2out-fast",
2209  .vector_size = sizeof (u32),
2210  .format_trace = format_snat_in2out_fast_trace,
2211  .type = VLIB_NODE_TYPE_INTERNAL,
2212
2213  .n_errors = ARRAY_LEN(snat_in2out_error_strings),
2214  .error_strings = snat_in2out_error_strings,
2215
2216  .runtime_data_bytes = sizeof (snat_runtime_t),
2217
2218  .n_next_nodes = SNAT_IN2OUT_N_NEXT,
2219
2220  /* edit / add dispositions here */
2221  .next_nodes = {
2222    [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
2223    [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
2224    [SNAT_IN2OUT_NEXT_SLOW_PATH] = "nat44-in2out-slowpath",
2225    [SNAT_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2226    [SNAT_IN2OUT_NEXT_REASS] = "nat44-in2out-reass",
2227  },
2228};
2229/* *INDENT-ON* */
2230
2231/*
2232 * fd.io coding-style-patch-verification: ON
2233 *
2234 * Local Variables:
2235 * eval: (c-set-style "gnu")
2236 * End:
2237 */
2238