xref: /freebsd-11-stable/sys/netpfil/ipfw/nat64/nat64lsn.h (revision c2f3f69e703342083f8ff38260a04a3c9ba9e91d)
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  * $FreeBSD$
30  */
31 
32 #ifndef	_IP_FW_NAT64LSN_H_
33 #define	_IP_FW_NAT64LSN_H_
34 
35 #include "ip_fw_nat64.h"
36 #include "nat64_translate.h"
37 
38 #define	NAT64_CHUNK_SIZE_BITS	6	/* 64 ports */
39 #define	NAT64_CHUNK_SIZE	(1 << NAT64_CHUNK_SIZE_BITS)
40 
41 #define	NAT64_MIN_PORT		1024
42 #define	NAT64_MIN_CHUNK		(NAT64_MIN_PORT >> NAT64_CHUNK_SIZE_BITS)
43 
44 struct st_ptr {
45 	uint8_t			idx;	/* index in nh->pg_ptr array.
46 					 * NOTE: it starts from 1.
47 					 */
48 	uint8_t			off;
49 };
50 #define	NAT64LSN_MAXPGPTR	((1 << (sizeof(uint8_t) * NBBY)) - 1)
51 #define	NAT64LSN_PGPTRMASKBITS	(sizeof(uint64_t) * NBBY)
52 #define	NAT64LSN_PGPTRNMASK	(roundup(NAT64LSN_MAXPGPTR,	\
53     NAT64LSN_PGPTRMASKBITS) / NAT64LSN_PGPTRMASKBITS)
54 
55 struct nat64lsn_portgroup;
56 /* sizeof(struct nat64lsn_host) = 64 + 64x2 + 8x8 = 256 bytes */
57 struct nat64lsn_host {
58 	struct rwlock	h_lock;		/* Host states lock */
59 
60 	struct in6_addr	addr;
61 	struct nat64lsn_host	*next;
62 	uint16_t	timestamp;	/* Last altered */
63 	uint16_t	hsize;		/* ports hash size */
64 	uint16_t	pg_used;	/* Number of portgroups used */
65 #define	NAT64LSN_REMAININGPG	8	/* Number of remaining PG before
66 					 * requesting of new chunk of indexes.
67 					 */
68 	uint16_t	pg_allocated;	/* Number of portgroups indexes
69 					 * allocated.
70 					 */
71 #define	NAT64LSN_HSIZE	64
72 	struct st_ptr	phash[NAT64LSN_HSIZE]; /* XXX: hardcoded size */
73 	/*
74 	 * PG indexes are stored in chunks with 32 elements.
75 	 * The maximum count is limited to 255 due to st_ptr->idx is uint8_t.
76 	 */
77 #define	NAT64LSN_PGIDX_CHUNK	32
78 #define	NAT64LSN_PGNIDX		(roundup(NAT64LSN_MAXPGPTR, \
79     NAT64LSN_PGIDX_CHUNK) / NAT64LSN_PGIDX_CHUNK)
80 	struct nat64lsn_portgroup **pg_ptr[NAT64LSN_PGNIDX]; /* PG indexes */
81 };
82 
83 #define	NAT64_RLOCK_ASSERT(h)	rw_assert(&(h)->h_lock, RA_RLOCKED)
84 #define	NAT64_WLOCK_ASSERT(h)	rw_assert(&(h)->h_lock, RA_WLOCKED)
85 
86 #define	NAT64_RLOCK(h)		rw_rlock(&(h)->h_lock)
87 #define	NAT64_RUNLOCK(h)	rw_runlock(&(h)->h_lock)
88 #define	NAT64_WLOCK(h)		rw_wlock(&(h)->h_lock)
89 #define	NAT64_WUNLOCK(h)	rw_wunlock(&(h)->h_lock)
90 #define	NAT64_LOCK(h)		NAT64_WLOCK(h)
91 #define	NAT64_UNLOCK(h)		NAT64_WUNLOCK(h)
92 #define	NAT64_LOCK_INIT(h) do {			\
93 	rw_init(&(h)->h_lock, "NAT64 host lock");	\
94 	} while (0)
95 
96 #define	NAT64_LOCK_DESTROY(h) do {			\
97 	rw_destroy(&(h)->h_lock);			\
98 	} while (0)
99 
100 /* Internal proto index */
101 #define	NAT_PROTO_TCP	1
102 #define	NAT_PROTO_UDP	2
103 #define	NAT_PROTO_ICMP	3
104 
105 #define	NAT_MAX_PROTO	4
106 extern uint8_t nat64lsn_rproto_map[NAT_MAX_PROTO];
107 
108 VNET_DECLARE(uint16_t, nat64lsn_eid);
109 #define	V_nat64lsn_eid		VNET(nat64lsn_eid)
110 #define	IPFW_TLV_NAT64LSN_NAME	IPFW_TLV_EACTION_NAME(V_nat64lsn_eid)
111 
112 /* Timestamp macro */
113 #define	_CT		((int)time_uptime % 65536)
114 #define	SET_AGE(x)	(x) = _CT
115 #define	GET_AGE(x)	((_CT >= (x)) ? _CT - (x) :	\
116 	(int)65536 + _CT - (x))
117 
118 #ifdef __LP64__
119 /* ffsl() is capable of checking 64-bit ints */
120 #define	_FFS64
121 #endif
122 
123 /* 16 bytes */
124 struct nat64lsn_state {
125 	union {
126 		struct {
127 			in_addr_t	faddr;	/* Remote IPv4 address */
128 			uint16_t	fport;	/* Remote IPv4 port */
129 			uint16_t	lport;	/* Local IPv6 port */
130 		}s;
131 		uint64_t		hkey;
132 	} u;
133 	uint8_t		nat_proto;
134 	uint8_t		flags;
135 	uint16_t	timestamp;
136 	struct st_ptr	cur; /* Index of portgroup in nat64lsn_host */
137 	struct st_ptr	next; /* Next entry index */
138 };
139 
140 /*
141  * 1024+32 bytes per 64 states, used to store state
142  * AND for outside-in state lookup
143  */
144 struct nat64lsn_portgroup {
145 	struct nat64lsn_host	*host;	/* IPv6 source host info */
146 	in_addr_t		aaddr;	/* Alias addr, network format */
147 	uint16_t		aport;	/* Base port */
148 	uint16_t		timestamp;
149 	uint8_t			nat_proto;
150 	uint8_t			spare[3];
151 	uint32_t		idx;
152 #ifdef _FFS64
153 	uint64_t		freemask;	/* Mask of free entries */
154 #else
155 	uint32_t		freemask[2];	/* Mask of free entries */
156 #endif
157 	struct nat64lsn_state	states[NAT64_CHUNK_SIZE]; /* State storage */
158 };
159 #ifdef _FFS64
160 #define	PG_MARK_BUSY_IDX(_pg, _idx)	(_pg)->freemask &= ~((uint64_t)1<<(_idx))
161 #define	PG_MARK_FREE_IDX(_pg, _idx)	(_pg)->freemask |= ((uint64_t)1<<(_idx))
162 #define	PG_IS_FREE_IDX(_pg, _idx)	((_pg)->freemask & ((uint64_t)1<<(_idx)))
163 #define	PG_IS_BUSY_IDX(_pg, _idx)	(PG_IS_FREE_IDX(_pg, _idx) == 0)
164 #define	PG_GET_FREE_IDX(_pg)		(ffsll((_pg)->freemask))
165 #define	PG_IS_EMPTY(_pg)		(((_pg)->freemask + 1) == 0)
166 #else
167 #define	PG_MARK_BUSY_IDX(_pg, _idx)	\
168 	(_pg)->freemask[(_idx) / 32] &= ~((u_long)1<<((_idx) % 32))
169 #define	PG_MARK_FREE_IDX(_pg, _idx)	\
170 	(_pg)->freemask[(_idx) / 32] |= ((u_long)1<<((_idx)  % 32))
171 #define	PG_IS_FREE_IDX(_pg, _idx)	\
172 	((_pg)->freemask[(_idx) / 32] & ((u_long)1<<((_idx) % 32)))
173 #define	PG_IS_BUSY_IDX(_pg, _idx)	(PG_IS_FREE_IDX(_pg, _idx) == 0)
174 #define	PG_GET_FREE_IDX(_pg)		_pg_get_free_idx(_pg)
175 #define	PG_IS_EMPTY(_pg)		\
176 	((((_pg)->freemask[0] + 1) == 0 && ((_pg)->freemask[1] + 1) == 0))
177 
178 static inline int
_pg_get_free_idx(const struct nat64lsn_portgroup * pg)179 _pg_get_free_idx(const struct nat64lsn_portgroup *pg)
180 {
181 	int i;
182 
183 	if ((i = ffsl(pg->freemask[0])) != 0)
184 		return (i);
185 	if ((i = ffsl(pg->freemask[1])) != 0)
186 		return (i + 32);
187 	return (0);
188 }
189 
190 #endif
191 
192 TAILQ_HEAD(nat64lsn_job_head, nat64lsn_job_item);
193 
194 struct nat64lsn_cfg {
195 	struct named_object	no;
196 	struct nat64lsn_portgroup	**pg;	/* XXX: array of pointers */
197 	struct nat64lsn_host	**ih;	/* Host hash */
198 	uint32_t	prefix4;	/* IPv4 prefix */
199 	uint32_t	pmask4;		/* IPv4 prefix mask */
200 	uint32_t	ihsize;		/* IPv6 host hash size */
201 	uint8_t		plen4;
202 	uint8_t		nomatch_verdict;/* What to return to ipfw on no-match */
203 
204 	uint32_t	ihcount;	/* Number of items in host hash */
205 	int		max_chunks;	/* Max chunks per client */
206 	int		agg_prefix_len;	/* Prefix length to count */
207 	int		agg_prefix_max;	/* Max hosts per agg prefix */
208 	uint32_t	jmaxlen;	/* Max jobqueue length */
209 	uint16_t	min_chunk;	/* Min port group # to use */
210 	uint16_t	max_chunk;	/* Max port group # to use */
211 	uint16_t	nh_delete_delay;	/* Stale host delete delay */
212 	uint16_t	pg_delete_delay;	/* Stale portgroup del delay */
213 	uint16_t	st_syn_ttl;	/* TCP syn expire */
214 	uint16_t	st_close_ttl;	/* TCP fin expire */
215 	uint16_t	st_estab_ttl;	/* TCP established expire */
216 	uint16_t	st_udp_ttl;	/* UDP expire */
217 	uint16_t	st_icmp_ttl;	/* ICMP expire */
218 	uint32_t	protochunks[NAT_MAX_PROTO];/* Number of chunks used */
219 	struct nat64_config	base;
220 #define	NAT64LSN_FLAGSMASK	(NAT64_LOG | NAT64_ALLOW_PRIVATE)
221 
222 	struct callout		periodic;
223 	struct callout		jcallout;
224 	struct ip_fw_chain	*ch;
225 	struct vnet		*vp;
226 	struct nat64lsn_job_head	jhead;
227 	int			jlen;
228 	char			name[64];	/* Nat instance name */
229 };
230 
231 struct nat64lsn_cfg *nat64lsn_init_instance(struct ip_fw_chain *ch,
232     size_t numaddr);
233 void nat64lsn_destroy_instance(struct nat64lsn_cfg *cfg);
234 void nat64lsn_start_instance(struct nat64lsn_cfg *cfg);
235 void nat64lsn_init_internal(void);
236 void nat64lsn_uninit_internal(void);
237 int ipfw_nat64lsn(struct ip_fw_chain *ch, struct ip_fw_args *args,
238     ipfw_insn *cmd, int *done);
239 
240 void
241 nat64lsn_dump_state(const struct nat64lsn_cfg *cfg,
242     const struct nat64lsn_portgroup *pg, const struct nat64lsn_state *st,
243     const char *px, int off);
244 /*
245  * Portgroup layout
246  * addr x nat_proto x port_off
247  *
248  */
249 
250 #define	_ADDR_PG_PROTO_COUNT	(65536 >> NAT64_CHUNK_SIZE_BITS)
251 #define	_ADDR_PG_COUNT		(_ADDR_PG_PROTO_COUNT * NAT_MAX_PROTO)
252 
253 #define	GET_ADDR_IDX(_cfg, _addr)	((_addr) - ((_cfg)->prefix4))
254 #define	__GET_PORTGROUP_IDX(_proto, _port)	\
255     ((_proto - 1) * _ADDR_PG_PROTO_COUNT +	\
256 	((_port) >> NAT64_CHUNK_SIZE_BITS))
257 
258 #define	_GET_PORTGROUP_IDX(_cfg, _addr, _proto, _port)	\
259     GET_ADDR_IDX(_cfg, _addr) * _ADDR_PG_COUNT +	\
260 	__GET_PORTGROUP_IDX(_proto, _port)
261 #define	GET_PORTGROUP(_cfg, _addr, _proto, _port)	\
262     ((_cfg)->pg[_GET_PORTGROUP_IDX(_cfg, _addr, _proto, _port)])
263 
264 #define	PORTGROUP_CHUNK(_nh, _idx)		\
265     ((_nh)->pg_ptr[(_idx)])
266 #define	PORTGROUP_BYSIDX(_cfg, _nh, _idx)	\
267     (PORTGROUP_CHUNK(_nh, (_idx - 1) / NAT64LSN_PGIDX_CHUNK) \
268 	[((_idx) - 1) % NAT64LSN_PGIDX_CHUNK])
269 
270 
271 /* Chained hash table */
272 #define CHT_FIND(_ph, _hsize, _PX, _x, _key) do {			\
273 	unsigned int _buck = _PX##hash(_key) & (_hsize - 1);		\
274 	_PX##lock(_ph, _buck);						\
275 	_x = _PX##first(_ph, _buck);					\
276 	for ( ; _x != NULL; _x = _PX##next(_x)) {			\
277 		if (_PX##cmp(_key, _PX##val(_x)))			\
278 			break;						\
279 	}								\
280 	if (_x == NULL)							\
281 		_PX##unlock(_ph, _buck);				\
282 } while(0)
283 
284 #define	CHT_UNLOCK_BUCK(_ph, _PX, _buck)				\
285 	_PX##unlock(_ph, _buck);
286 
287 #define	CHT_UNLOCK_KEY(_ph, _hsize, _PX, _key) do {			\
288 	unsigned int _buck = _PX##hash(_key) & (_hsize - 1);		\
289 	_PX##unlock(_ph, _buck);					\
290 } while(0)
291 
292 #define	CHT_INSERT_HEAD(_ph, _hsize, _PX, _i) do {			\
293 	unsigned int _buck = _PX##hash(_PX##val(_i)) & (_hsize - 1);	\
294 	_PX##lock(_ph, _buck);						\
295 	_PX##next(_i) = _PX##first(_ph, _buck);				\
296 	_PX##first(_ph, _buck) = _i;					\
297 	_PX##unlock(_ph, _buck);					\
298 } while(0)
299 
300 #define	CHT_REMOVE(_ph, _hsize, _PX, _x, _tmp, _key) do {		\
301 	unsigned int _buck = _PX##hash(_key) & (_hsize - 1);		\
302 	_PX##lock(_ph, _buck);						\
303 	_x = _PX##first(_ph, _buck);					\
304 	_tmp = NULL;							\
305 	for ( ; _x != NULL; _tmp = _x, _x = _PX##next(_x)) {		\
306 		if (_PX##cmp(_key, _PX##val(_x)))			\
307 			break;						\
308 	}								\
309 	if (_x != NULL) {						\
310 		if (_tmp == NULL)					\
311 			_PX##first(_ph, _buck) = _PX##next(_x);		\
312 		else							\
313 			_PX##next(_tmp) = _PX##next(_x);		\
314 	}								\
315 	_PX##unlock(_ph, _buck);					\
316 } while(0)
317 
318 #define	CHT_FOREACH_SAFE(_ph, _hsize, _PX, _x, _tmp, _cb, _arg) do {	\
319 	for (unsigned int _i = 0; _i < _hsize; _i++) {			\
320 		_PX##lock(_ph, _i);					\
321 		_x = _PX##first(_ph, _i);				\
322 		_tmp = NULL;						\
323 		for (; _x != NULL; _tmp = _x, _x = _PX##next(_x)) {	\
324 			if (_cb(_x, _arg) == 0)				\
325 				continue;				\
326 			if (_tmp == NULL)				\
327 				_PX##first(_ph, _i) = _PX##next(_x);	\
328 			else						\
329 				_tmp = _PX##next(_x);			\
330 		}							\
331 		_PX##unlock(_ph, _i);					\
332 	}								\
333 } while(0)
334 
335 #define	CHT_RESIZE(_ph, _hsize, _nph, _nhsize, _PX, _x, _y) do {	\
336 	unsigned int _buck;						\
337 	for (unsigned int _i = 0; _i < _hsize; _i++) {			\
338 		_x = _PX##first(_ph, _i);				\
339 		_y = _x;						\
340 		while (_y != NULL) {					\
341 			_buck = _PX##hash(_PX##val(_x)) & (_nhsize - 1);\
342 			_y = _PX##next(_x);				\
343 			_PX##next(_x) = _PX##first(_nph, _buck);	\
344 			_PX##first(_nph, _buck) = _x;			\
345 		}							\
346 	}								\
347 } while(0)
348 
349 #endif /* _IP_FW_NAT64LSN_H_ */
350 
351