1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2015-2019 Yandex LLC
5 * Copyright (c) 2015 Alexander V. Chernikov <melifaro@FreeBSD.org>
6 * Copyright (c) 2015-2019 Andrey V. Elsukov <ae@FreeBSD.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/counter.h>
36#include <sys/errno.h>
37#include <sys/kernel.h>
38#include <sys/lock.h>
39#include <sys/malloc.h>
40#include <sys/mbuf.h>
41#include <sys/module.h>
42#include <sys/rmlock.h>
43#include <sys/rwlock.h>
44#include <sys/socket.h>
45#include <sys/sockopt.h>
46#include <sys/queue.h>
47#include <sys/syslog.h>
48#include <sys/sysctl.h>
49
50#include <net/if.h>
51#include <net/if_var.h>
52#include <net/pfil.h>
53#include <net/route.h>
54#include <net/vnet.h>
55
56#include <netinet/in.h>
57#include <netinet/ip_var.h>
58#include <netinet/ip_fw.h>
59#include <netinet6/in6_var.h>
60#include <netinet6/ip6_var.h>
61#include <netinet6/ip_fw_nat64.h>
62
63#include <netpfil/ipfw/ip_fw_private.h>
64
65#include "nat64stl.h"
66
67VNET_DEFINE(uint16_t, nat64stl_eid) = 0;
68
69static struct nat64stl_cfg *nat64stl_alloc_config(const char *name,
70    uint8_t set);
71static void nat64stl_free_config(struct nat64stl_cfg *cfg);
72static struct nat64stl_cfg *nat64stl_find(struct namedobj_instance *ni,
73    const char *name, uint8_t set);
74
75static struct nat64stl_cfg *
76nat64stl_alloc_config(const char *name, uint8_t set)
77{
78	struct nat64stl_cfg *cfg;
79
80	cfg = malloc(sizeof(struct nat64stl_cfg), M_IPFW, M_WAITOK | M_ZERO);
81	COUNTER_ARRAY_ALLOC(cfg->base.stats.cnt, NAT64STATS, M_WAITOK);
82	cfg->no.name = cfg->name;
83	cfg->no.etlv = IPFW_TLV_NAT64STL_NAME;
84	cfg->no.set = set;
85	strlcpy(cfg->name, name, sizeof(cfg->name));
86	return (cfg);
87}
88
89static void
90nat64stl_free_config(struct nat64stl_cfg *cfg)
91{
92
93	COUNTER_ARRAY_FREE(cfg->base.stats.cnt, NAT64STATS);
94	free(cfg, M_IPFW);
95}
96
97static void
98nat64stl_export_config(struct ip_fw_chain *ch, struct nat64stl_cfg *cfg,
99    ipfw_nat64stl_cfg *uc)
100{
101	struct named_object *no;
102
103	uc->prefix6 = cfg->base.plat_prefix;
104	uc->plen6 = cfg->base.plat_plen;
105	uc->flags = cfg->base.flags & NAT64STL_FLAGSMASK;
106	uc->set = cfg->no.set;
107	strlcpy(uc->name, cfg->no.name, sizeof(uc->name));
108
109	no = ipfw_objhash_lookup_table_kidx(ch, cfg->map64);
110	ipfw_export_obj_ntlv(no, &uc->ntlv6);
111	no = ipfw_objhash_lookup_table_kidx(ch, cfg->map46);
112	ipfw_export_obj_ntlv(no, &uc->ntlv4);
113}
114
115struct nat64stl_dump_arg {
116	struct ip_fw_chain *ch;
117	struct sockopt_data *sd;
118};
119
120static int
121export_config_cb(struct namedobj_instance *ni, struct named_object *no,
122    void *arg)
123{
124	struct nat64stl_dump_arg *da = (struct nat64stl_dump_arg *)arg;
125	ipfw_nat64stl_cfg *uc;
126
127	uc = (ipfw_nat64stl_cfg *)ipfw_get_sopt_space(da->sd, sizeof(*uc));
128	nat64stl_export_config(da->ch, (struct nat64stl_cfg *)no, uc);
129	return (0);
130}
131
132static struct nat64stl_cfg *
133nat64stl_find(struct namedobj_instance *ni, const char *name, uint8_t set)
134{
135	struct nat64stl_cfg *cfg;
136
137	cfg = (struct nat64stl_cfg *)ipfw_objhash_lookup_name_type(ni, set,
138	    IPFW_TLV_NAT64STL_NAME, name);
139
140	return (cfg);
141}
142
143
144static int
145nat64stl_create_internal(struct ip_fw_chain *ch, struct nat64stl_cfg *cfg,
146    ipfw_nat64stl_cfg *i)
147{
148
149	IPFW_UH_WLOCK_ASSERT(ch);
150
151	if (ipfw_objhash_alloc_idx(CHAIN_TO_SRV(ch), &cfg->no.kidx) != 0)
152		return (ENOSPC);
153	cfg->base.flags |= NAT64STL_KIDX;
154
155	if (ipfw_ref_table(ch, &i->ntlv4, &cfg->map46) != 0)
156		return (EINVAL);
157	cfg->base.flags |= NAT64STL_46T;
158
159	if (ipfw_ref_table(ch, &i->ntlv6, &cfg->map64) != 0)
160		return (EINVAL);
161	cfg->base.flags |= NAT64STL_64T;
162
163	ipfw_objhash_add(CHAIN_TO_SRV(ch), &cfg->no);
164
165	return (0);
166}
167
168/*
169 * Creates new nat64 instance.
170 * Data layout (v0)(current):
171 * Request: [ ipfw_obj_lheader ipfw_nat64stl_cfg ]
172 *
173 * Returns 0 on success
174 */
175static int
176nat64stl_create(struct ip_fw_chain *ch, ip_fw3_opheader *op3,
177    struct sockopt_data *sd)
178{
179	ipfw_obj_lheader *olh;
180	ipfw_nat64stl_cfg *uc;
181	struct namedobj_instance *ni;
182	struct nat64stl_cfg *cfg;
183	int error;
184
185	if (sd->valsize != sizeof(*olh) + sizeof(*uc))
186		return (EINVAL);
187
188	olh = (ipfw_obj_lheader *)sd->kbuf;
189	uc = (ipfw_nat64stl_cfg *)(olh + 1);
190
191	if (ipfw_check_object_name_generic(uc->name) != 0)
192		return (EINVAL);
193	if (uc->set >= IPFW_MAX_SETS ||
194	    nat64_check_prefix6(&uc->prefix6, uc->plen6) != 0)
195		return (EINVAL);
196
197	/* XXX: check types of tables */
198
199	ni = CHAIN_TO_SRV(ch);
200	error = 0;
201
202	IPFW_UH_RLOCK(ch);
203	if (nat64stl_find(ni, uc->name, uc->set) != NULL) {
204		IPFW_UH_RUNLOCK(ch);
205		return (EEXIST);
206	}
207	IPFW_UH_RUNLOCK(ch);
208
209	cfg = nat64stl_alloc_config(uc->name, uc->set);
210	cfg->base.plat_prefix = uc->prefix6;
211	cfg->base.plat_plen = uc->plen6;
212	cfg->base.flags = (uc->flags & NAT64STL_FLAGSMASK) | NAT64_PLATPFX;
213	if (IN6_IS_ADDR_WKPFX(&cfg->base.plat_prefix))
214		cfg->base.flags |= NAT64_WKPFX;
215
216	IPFW_UH_WLOCK(ch);
217
218	if (nat64stl_find(ni, uc->name, uc->set) != NULL) {
219		IPFW_UH_WUNLOCK(ch);
220		nat64stl_free_config(cfg);
221		return (EEXIST);
222	}
223	error = nat64stl_create_internal(ch, cfg, uc);
224	if (error == 0) {
225		/* Okay, let's link data */
226		SRV_OBJECT(ch, cfg->no.kidx) = cfg;
227		IPFW_UH_WUNLOCK(ch);
228		return (0);
229	}
230
231	if (cfg->base.flags & NAT64STL_KIDX)
232		ipfw_objhash_free_idx(ni, cfg->no.kidx);
233	if (cfg->base.flags & NAT64STL_46T)
234		ipfw_unref_table(ch, cfg->map46);
235	if (cfg->base.flags & NAT64STL_64T)
236		ipfw_unref_table(ch, cfg->map64);
237
238	IPFW_UH_WUNLOCK(ch);
239	nat64stl_free_config(cfg);
240	return (error);
241}
242
243/*
244 * Change existing nat64stl instance configuration.
245 * Data layout (v0)(current):
246 * Request: [ ipfw_obj_header ipfw_nat64stl_cfg ]
247 * Reply: [ ipfw_obj_header ipfw_nat64stl_cfg ]
248 *
249 * Returns 0 on success
250 */
251static int
252nat64stl_config(struct ip_fw_chain *ch, ip_fw3_opheader *op,
253    struct sockopt_data *sd)
254{
255	ipfw_obj_header *oh;
256	ipfw_nat64stl_cfg *uc;
257	struct nat64stl_cfg *cfg;
258	struct namedobj_instance *ni;
259
260	if (sd->valsize != sizeof(*oh) + sizeof(*uc))
261		return (EINVAL);
262
263	oh = (ipfw_obj_header *)ipfw_get_sopt_space(sd,
264	    sizeof(*oh) + sizeof(*uc));
265	uc = (ipfw_nat64stl_cfg *)(oh + 1);
266
267	if (ipfw_check_object_name_generic(oh->ntlv.name) != 0 ||
268	    oh->ntlv.set >= IPFW_MAX_SETS)
269		return (EINVAL);
270
271	ni = CHAIN_TO_SRV(ch);
272	if (sd->sopt->sopt_dir == SOPT_GET) {
273		IPFW_UH_RLOCK(ch);
274		cfg = nat64stl_find(ni, oh->ntlv.name, oh->ntlv.set);
275		if (cfg == NULL) {
276			IPFW_UH_RUNLOCK(ch);
277			return (EEXIST);
278		}
279		nat64stl_export_config(ch, cfg, uc);
280		IPFW_UH_RUNLOCK(ch);
281		return (0);
282	}
283
284	IPFW_UH_WLOCK(ch);
285	cfg = nat64stl_find(ni, oh->ntlv.name, oh->ntlv.set);
286	if (cfg == NULL) {
287		IPFW_UH_WUNLOCK(ch);
288		return (EEXIST);
289	}
290
291	/*
292	 * For now allow to change only following values:
293	 *  flags.
294	 */
295	cfg->base.flags &= ~NAT64STL_FLAGSMASK;
296	cfg->base.flags |= uc->flags & NAT64STL_FLAGSMASK;
297
298	IPFW_UH_WUNLOCK(ch);
299	return (0);
300}
301
302static void
303nat64stl_detach_config(struct ip_fw_chain *ch, struct nat64stl_cfg *cfg)
304{
305
306	IPFW_UH_WLOCK_ASSERT(ch);
307
308	ipfw_objhash_del(CHAIN_TO_SRV(ch), &cfg->no);
309	ipfw_objhash_free_idx(CHAIN_TO_SRV(ch), cfg->no.kidx);
310	ipfw_unref_table(ch, cfg->map46);
311	ipfw_unref_table(ch, cfg->map64);
312}
313
314/*
315 * Destroys nat64 instance.
316 * Data layout (v0)(current):
317 * Request: [ ipfw_obj_header ]
318 *
319 * Returns 0 on success
320 */
321static int
322nat64stl_destroy(struct ip_fw_chain *ch, ip_fw3_opheader *op3,
323    struct sockopt_data *sd)
324{
325	ipfw_obj_header *oh;
326	struct nat64stl_cfg *cfg;
327
328	if (sd->valsize != sizeof(*oh))
329		return (EINVAL);
330
331	oh = (ipfw_obj_header *)sd->kbuf;
332	if (ipfw_check_object_name_generic(oh->ntlv.name) != 0)
333		return (EINVAL);
334
335	IPFW_UH_WLOCK(ch);
336	cfg = nat64stl_find(CHAIN_TO_SRV(ch), oh->ntlv.name, oh->ntlv.set);
337	if (cfg == NULL) {
338		IPFW_UH_WUNLOCK(ch);
339		return (ESRCH);
340	}
341	if (cfg->no.refcnt > 0) {
342		IPFW_UH_WUNLOCK(ch);
343		return (EBUSY);
344	}
345
346	ipfw_reset_eaction_instance(ch, V_nat64stl_eid, cfg->no.kidx);
347	SRV_OBJECT(ch, cfg->no.kidx) = NULL;
348	nat64stl_detach_config(ch, cfg);
349	IPFW_UH_WUNLOCK(ch);
350
351	nat64stl_free_config(cfg);
352	return (0);
353}
354
355/*
356 * Lists all nat64stl instances currently available in kernel.
357 * Data layout (v0)(current):
358 * Request: [ ipfw_obj_lheader ]
359 * Reply: [ ipfw_obj_lheader ipfw_nat64stl_cfg x N ]
360 *
361 * Returns 0 on success
362 */
363static int
364nat64stl_list(struct ip_fw_chain *ch, ip_fw3_opheader *op3,
365    struct sockopt_data *sd)
366{
367	ipfw_obj_lheader *olh;
368	struct nat64stl_dump_arg da;
369
370	/* Check minimum header size */
371	if (sd->valsize < sizeof(ipfw_obj_lheader))
372		return (EINVAL);
373
374	olh = (ipfw_obj_lheader *)ipfw_get_sopt_header(sd, sizeof(*olh));
375
376	IPFW_UH_RLOCK(ch);
377	olh->count = ipfw_objhash_count_type(CHAIN_TO_SRV(ch),
378	    IPFW_TLV_NAT64STL_NAME);
379	olh->objsize = sizeof(ipfw_nat64stl_cfg);
380	olh->size = sizeof(*olh) + olh->count * olh->objsize;
381
382	if (sd->valsize < olh->size) {
383		IPFW_UH_RUNLOCK(ch);
384		return (ENOMEM);
385	}
386	memset(&da, 0, sizeof(da));
387	da.ch = ch;
388	da.sd = sd;
389	ipfw_objhash_foreach_type(CHAIN_TO_SRV(ch), export_config_cb,
390	    &da, IPFW_TLV_NAT64STL_NAME);
391	IPFW_UH_RUNLOCK(ch);
392
393	return (0);
394}
395
396#define	__COPY_STAT_FIELD(_cfg, _stats, _field)	\
397	(_stats)->_field = NAT64STAT_FETCH(&(_cfg)->base.stats, _field)
398static void
399export_stats(struct ip_fw_chain *ch, struct nat64stl_cfg *cfg,
400    struct ipfw_nat64stl_stats *stats)
401{
402
403	__COPY_STAT_FIELD(cfg, stats, opcnt64);
404	__COPY_STAT_FIELD(cfg, stats, opcnt46);
405	__COPY_STAT_FIELD(cfg, stats, ofrags);
406	__COPY_STAT_FIELD(cfg, stats, ifrags);
407	__COPY_STAT_FIELD(cfg, stats, oerrors);
408	__COPY_STAT_FIELD(cfg, stats, noroute4);
409	__COPY_STAT_FIELD(cfg, stats, noroute6);
410	__COPY_STAT_FIELD(cfg, stats, noproto);
411	__COPY_STAT_FIELD(cfg, stats, nomem);
412	__COPY_STAT_FIELD(cfg, stats, dropped);
413}
414
415/*
416 * Get nat64stl statistics.
417 * Data layout (v0)(current):
418 * Request: [ ipfw_obj_header ]
419 * Reply: [ ipfw_obj_header ipfw_obj_ctlv [ uint64_t x N ]]
420 *
421 * Returns 0 on success
422 */
423static int
424nat64stl_stats(struct ip_fw_chain *ch, ip_fw3_opheader *op,
425    struct sockopt_data *sd)
426{
427	struct ipfw_nat64stl_stats stats;
428	struct nat64stl_cfg *cfg;
429	ipfw_obj_header *oh;
430	ipfw_obj_ctlv *ctlv;
431	size_t sz;
432
433	sz = sizeof(ipfw_obj_header) + sizeof(ipfw_obj_ctlv) + sizeof(stats);
434	if (sd->valsize % sizeof(uint64_t))
435		return (EINVAL);
436	if (sd->valsize < sz)
437		return (ENOMEM);
438	oh = (ipfw_obj_header *)ipfw_get_sopt_header(sd, sz);
439	if (oh == NULL)
440		return (EINVAL);
441	memset(&stats, 0, sizeof(stats));
442
443	IPFW_UH_RLOCK(ch);
444	cfg = nat64stl_find(CHAIN_TO_SRV(ch), oh->ntlv.name, oh->ntlv.set);
445	if (cfg == NULL) {
446		IPFW_UH_RUNLOCK(ch);
447		return (ESRCH);
448	}
449	export_stats(ch, cfg, &stats);
450	IPFW_UH_RUNLOCK(ch);
451
452	ctlv = (ipfw_obj_ctlv *)(oh + 1);
453	memset(ctlv, 0, sizeof(*ctlv));
454	ctlv->head.type = IPFW_TLV_COUNTERS;
455	ctlv->head.length = sz - sizeof(ipfw_obj_header);
456	ctlv->count = sizeof(stats) / sizeof(uint64_t);
457	ctlv->objsize = sizeof(uint64_t);
458	ctlv->version = IPFW_NAT64_VERSION;
459	memcpy(ctlv + 1, &stats, sizeof(stats));
460	return (0);
461}
462
463/*
464 * Reset nat64stl statistics.
465 * Data layout (v0)(current):
466 * Request: [ ipfw_obj_header ]
467 *
468 * Returns 0 on success
469 */
470static int
471nat64stl_reset_stats(struct ip_fw_chain *ch, ip_fw3_opheader *op,
472    struct sockopt_data *sd)
473{
474	struct nat64stl_cfg *cfg;
475	ipfw_obj_header *oh;
476
477	if (sd->valsize != sizeof(*oh))
478		return (EINVAL);
479	oh = (ipfw_obj_header *)sd->kbuf;
480	if (ipfw_check_object_name_generic(oh->ntlv.name) != 0 ||
481	    oh->ntlv.set >= IPFW_MAX_SETS)
482		return (EINVAL);
483
484	IPFW_UH_WLOCK(ch);
485	cfg = nat64stl_find(CHAIN_TO_SRV(ch), oh->ntlv.name, oh->ntlv.set);
486	if (cfg == NULL) {
487		IPFW_UH_WUNLOCK(ch);
488		return (ESRCH);
489	}
490	COUNTER_ARRAY_ZERO(cfg->base.stats.cnt, NAT64STATS);
491	IPFW_UH_WUNLOCK(ch);
492	return (0);
493}
494
495static struct ipfw_sopt_handler	scodes[] = {
496
497	{ IP_FW_NAT64STL_CREATE, 0,	HDIR_SET,	nat64stl_create },
498	{ IP_FW_NAT64STL_DESTROY,0,	HDIR_SET,	nat64stl_destroy },
499	{ IP_FW_NAT64STL_CONFIG, 0,	HDIR_BOTH,	nat64stl_config },
500	{ IP_FW_NAT64STL_LIST,   0,	HDIR_GET,	nat64stl_list },
501	{ IP_FW_NAT64STL_STATS,  0,	HDIR_GET,	nat64stl_stats },
502	{ IP_FW_NAT64STL_RESET_STATS,0,	HDIR_SET,	nat64stl_reset_stats },
503};
504
505static int
506nat64stl_classify(ipfw_insn *cmd, uint16_t *puidx, uint8_t *ptype)
507{
508	ipfw_insn *icmd;
509
510	icmd = cmd - 1;
511	if (icmd->opcode != O_EXTERNAL_ACTION ||
512	    icmd->arg1 != V_nat64stl_eid)
513		return (1);
514
515	*puidx = cmd->arg1;
516	*ptype = 0;
517	return (0);
518}
519
520static void
521nat64stl_update_arg1(ipfw_insn *cmd, uint16_t idx)
522{
523
524	cmd->arg1 = idx;
525}
526
527static int
528nat64stl_findbyname(struct ip_fw_chain *ch, struct tid_info *ti,
529    struct named_object **pno)
530{
531	int err;
532
533	err = ipfw_objhash_find_type(CHAIN_TO_SRV(ch), ti,
534	    IPFW_TLV_NAT64STL_NAME, pno);
535	return (err);
536}
537
538static struct named_object *
539nat64stl_findbykidx(struct ip_fw_chain *ch, uint16_t idx)
540{
541	struct namedobj_instance *ni;
542	struct named_object *no;
543
544	IPFW_UH_WLOCK_ASSERT(ch);
545	ni = CHAIN_TO_SRV(ch);
546	no = ipfw_objhash_lookup_kidx(ni, idx);
547	KASSERT(no != NULL, ("NAT with index %d not found", idx));
548
549	return (no);
550}
551
552static int
553nat64stl_manage_sets(struct ip_fw_chain *ch, uint16_t set, uint8_t new_set,
554    enum ipfw_sets_cmd cmd)
555{
556
557	return (ipfw_obj_manage_sets(CHAIN_TO_SRV(ch), IPFW_TLV_NAT64STL_NAME,
558	    set, new_set, cmd));
559}
560
561static struct opcode_obj_rewrite opcodes[] = {
562	{
563		.opcode = O_EXTERNAL_INSTANCE,
564		.etlv = IPFW_TLV_EACTION /* just show it isn't table */,
565		.classifier = nat64stl_classify,
566		.update = nat64stl_update_arg1,
567		.find_byname = nat64stl_findbyname,
568		.find_bykidx = nat64stl_findbykidx,
569		.manage_sets = nat64stl_manage_sets,
570	},
571};
572
573static int
574destroy_config_cb(struct namedobj_instance *ni, struct named_object *no,
575    void *arg)
576{
577	struct nat64stl_cfg *cfg;
578	struct ip_fw_chain *ch;
579
580	ch = (struct ip_fw_chain *)arg;
581	cfg = (struct nat64stl_cfg *)SRV_OBJECT(ch, no->kidx);
582	SRV_OBJECT(ch, no->kidx) = NULL;
583	nat64stl_detach_config(ch, cfg);
584	nat64stl_free_config(cfg);
585	return (0);
586}
587
588int
589nat64stl_init(struct ip_fw_chain *ch, int first)
590{
591
592	V_nat64stl_eid = ipfw_add_eaction(ch, ipfw_nat64stl, "nat64stl");
593	if (V_nat64stl_eid == 0)
594		return (ENXIO);
595	IPFW_ADD_SOPT_HANDLER(first, scodes);
596	IPFW_ADD_OBJ_REWRITER(first, opcodes);
597	return (0);
598}
599
600void
601nat64stl_uninit(struct ip_fw_chain *ch, int last)
602{
603
604	IPFW_DEL_OBJ_REWRITER(last, opcodes);
605	IPFW_DEL_SOPT_HANDLER(last, scodes);
606	ipfw_del_eaction(ch, V_nat64stl_eid);
607	/*
608	 * Since we already have deregistered external action,
609	 * our named objects become unaccessible via rules, because
610	 * all rules were truncated by ipfw_del_eaction().
611	 * So, we can unlink and destroy our named objects without holding
612	 * IPFW_WLOCK().
613	 */
614	IPFW_UH_WLOCK(ch);
615	ipfw_objhash_foreach_type(CHAIN_TO_SRV(ch), destroy_config_cb, ch,
616	    IPFW_TLV_NAT64STL_NAME);
617	V_nat64stl_eid = 0;
618	IPFW_UH_WUNLOCK(ch);
619}
620
621