xref: /linux/include/net/xfrm.h (revision 14b9f27886ce69c5f11445d107dd020f6fc5754b)
1 #ifndef _NET_XFRM_H
2 #define _NET_XFRM_H
3 
4 #include <linux/compiler.h>
5 #include <linux/xfrm.h>
6 #include <linux/spinlock.h>
7 #include <linux/list.h>
8 #include <linux/skbuff.h>
9 #include <linux/socket.h>
10 #include <linux/pfkeyv2.h>
11 #include <linux/ipsec.h>
12 #include <linux/in6.h>
13 #include <linux/mutex.h>
14 #include <linux/audit.h>
15 #include <linux/slab.h>
16 
17 #include <net/sock.h>
18 #include <net/dst.h>
19 #include <net/ip.h>
20 #include <net/route.h>
21 #include <net/ipv6.h>
22 #include <net/ip6_fib.h>
23 #include <net/flow.h>
24 
25 #include <linux/interrupt.h>
26 
27 #ifdef CONFIG_XFRM_STATISTICS
28 #include <net/snmp.h>
29 #endif
30 
31 #define XFRM_PROTO_ESP		50
32 #define XFRM_PROTO_AH		51
33 #define XFRM_PROTO_COMP		108
34 #define XFRM_PROTO_IPIP		4
35 #define XFRM_PROTO_IPV6		41
36 #define XFRM_PROTO_ROUTING	IPPROTO_ROUTING
37 #define XFRM_PROTO_DSTOPTS	IPPROTO_DSTOPTS
38 
39 #define XFRM_ALIGN4(len)	(((len) + 3) & ~3)
40 #define XFRM_ALIGN8(len)	(((len) + 7) & ~7)
41 #define MODULE_ALIAS_XFRM_MODE(family, encap) \
42 	MODULE_ALIAS("xfrm-mode-" __stringify(family) "-" __stringify(encap))
43 #define MODULE_ALIAS_XFRM_TYPE(family, proto) \
44 	MODULE_ALIAS("xfrm-type-" __stringify(family) "-" __stringify(proto))
45 
46 #ifdef CONFIG_XFRM_STATISTICS
47 #define XFRM_INC_STATS(net, field)	SNMP_INC_STATS((net)->mib.xfrm_statistics, field)
48 #define XFRM_INC_STATS_BH(net, field)	SNMP_INC_STATS_BH((net)->mib.xfrm_statistics, field)
49 #define XFRM_INC_STATS_USER(net, field)	SNMP_INC_STATS_USER((net)-mib.xfrm_statistics, field)
50 #else
51 #define XFRM_INC_STATS(net, field)	((void)(net))
52 #define XFRM_INC_STATS_BH(net, field)	((void)(net))
53 #define XFRM_INC_STATS_USER(net, field)	((void)(net))
54 #endif
55 
56 extern struct mutex xfrm_cfg_mutex;
57 
58 /* Organization of SPD aka "XFRM rules"
59    ------------------------------------
60 
61    Basic objects:
62    - policy rule, struct xfrm_policy (=SPD entry)
63    - bundle of transformations, struct dst_entry == struct xfrm_dst (=SA bundle)
64    - instance of a transformer, struct xfrm_state (=SA)
65    - template to clone xfrm_state, struct xfrm_tmpl
66 
67    SPD is plain linear list of xfrm_policy rules, ordered by priority.
68    (To be compatible with existing pfkeyv2 implementations,
69    many rules with priority of 0x7fffffff are allowed to exist and
70    such rules are ordered in an unpredictable way, thanks to bsd folks.)
71 
72    Lookup is plain linear search until the first match with selector.
73 
74    If "action" is "block", then we prohibit the flow, otherwise:
75    if "xfrms_nr" is zero, the flow passes untransformed. Otherwise,
76    policy entry has list of up to XFRM_MAX_DEPTH transformations,
77    described by templates xfrm_tmpl. Each template is resolved
78    to a complete xfrm_state (see below) and we pack bundle of transformations
79    to a dst_entry returned to requestor.
80 
81    dst -. xfrm  .-> xfrm_state #1
82     |---. child .-> dst -. xfrm .-> xfrm_state #2
83                      |---. child .-> dst -. xfrm .-> xfrm_state #3
84                                       |---. child .-> NULL
85 
86    Bundles are cached at xrfm_policy struct (field ->bundles).
87 
88 
89    Resolution of xrfm_tmpl
90    -----------------------
91    Template contains:
92    1. ->mode		Mode: transport or tunnel
93    2. ->id.proto	Protocol: AH/ESP/IPCOMP
94    3. ->id.daddr	Remote tunnel endpoint, ignored for transport mode.
95       Q: allow to resolve security gateway?
96    4. ->id.spi          If not zero, static SPI.
97    5. ->saddr		Local tunnel endpoint, ignored for transport mode.
98    6. ->algos		List of allowed algos. Plain bitmask now.
99       Q: ealgos, aalgos, calgos. What a mess...
100    7. ->share		Sharing mode.
101       Q: how to implement private sharing mode? To add struct sock* to
102       flow id?
103 
104    Having this template we search through SAD searching for entries
105    with appropriate mode/proto/algo, permitted by selector.
106    If no appropriate entry found, it is requested from key manager.
107 
108    PROBLEMS:
109    Q: How to find all the bundles referring to a physical path for
110       PMTU discovery? Seems, dst should contain list of all parents...
111       and enter to infinite locking hierarchy disaster.
112       No! It is easier, we will not search for them, let them find us.
113       We add genid to each dst plus pointer to genid of raw IP route,
114       pmtu disc will update pmtu on raw IP route and increase its genid.
115       dst_check() will see this for top level and trigger resyncing
116       metrics. Plus, it will be made via sk->sk_dst_cache. Solved.
117  */
118 
119 struct xfrm_state_walk {
120 	struct list_head	all;
121 	u8			state;
122 	union {
123 		u8		dying;
124 		u8		proto;
125 	};
126 	u32			seq;
127 };
128 
129 /* Full description of state of transformer. */
130 struct xfrm_state {
131 #ifdef CONFIG_NET_NS
132 	struct net		*xs_net;
133 #endif
134 	union {
135 		struct hlist_node	gclist;
136 		struct hlist_node	bydst;
137 	};
138 	struct hlist_node	bysrc;
139 	struct hlist_node	byspi;
140 
141 	atomic_t		refcnt;
142 	spinlock_t		lock;
143 
144 	struct xfrm_id		id;
145 	struct xfrm_selector	sel;
146 	struct xfrm_mark	mark;
147 	u32			tfcpad;
148 
149 	u32			genid;
150 
151 	/* Key manager bits */
152 	struct xfrm_state_walk	km;
153 
154 	/* Parameters of this state. */
155 	struct {
156 		u32		reqid;
157 		u8		mode;
158 		u8		replay_window;
159 		u8		aalgo, ealgo, calgo;
160 		u8		flags;
161 		u16		family;
162 		xfrm_address_t	saddr;
163 		int		header_len;
164 		int		trailer_len;
165 	} props;
166 
167 	struct xfrm_lifetime_cfg lft;
168 
169 	/* Data for transformer */
170 	struct xfrm_algo_auth	*aalg;
171 	struct xfrm_algo	*ealg;
172 	struct xfrm_algo	*calg;
173 	struct xfrm_algo_aead	*aead;
174 
175 	/* Data for encapsulator */
176 	struct xfrm_encap_tmpl	*encap;
177 
178 	/* Data for care-of address */
179 	xfrm_address_t	*coaddr;
180 
181 	/* IPComp needs an IPIP tunnel for handling uncompressed packets */
182 	struct xfrm_state	*tunnel;
183 
184 	/* If a tunnel, number of users + 1 */
185 	atomic_t		tunnel_users;
186 
187 	/* State for replay detection */
188 	struct xfrm_replay_state replay;
189 	struct xfrm_replay_state_esn *replay_esn;
190 
191 	/* Replay detection state at the time we sent the last notification */
192 	struct xfrm_replay_state preplay;
193 	struct xfrm_replay_state_esn *preplay_esn;
194 
195 	/* The functions for replay detection. */
196 	struct xfrm_replay	*repl;
197 
198 	/* internal flag that only holds state for delayed aevent at the
199 	 * moment
200 	*/
201 	u32			xflags;
202 
203 	/* Replay detection notification settings */
204 	u32			replay_maxage;
205 	u32			replay_maxdiff;
206 
207 	/* Replay detection notification timer */
208 	struct timer_list	rtimer;
209 
210 	/* Statistics */
211 	struct xfrm_stats	stats;
212 
213 	struct xfrm_lifetime_cur curlft;
214 	struct tasklet_hrtimer	mtimer;
215 
216 	/* Last used time */
217 	unsigned long		lastused;
218 
219 	/* Reference to data common to all the instances of this
220 	 * transformer. */
221 	const struct xfrm_type	*type;
222 	struct xfrm_mode	*inner_mode;
223 	struct xfrm_mode	*inner_mode_iaf;
224 	struct xfrm_mode	*outer_mode;
225 
226 	/* Security context */
227 	struct xfrm_sec_ctx	*security;
228 
229 	/* Private data of this transformer, format is opaque,
230 	 * interpreted by xfrm_type methods. */
231 	void			*data;
232 };
233 
234 static inline struct net *xs_net(struct xfrm_state *x)
235 {
236 	return read_pnet(&x->xs_net);
237 }
238 
239 /* xflags - make enum if more show up */
240 #define XFRM_TIME_DEFER	1
241 
242 enum {
243 	XFRM_STATE_VOID,
244 	XFRM_STATE_ACQ,
245 	XFRM_STATE_VALID,
246 	XFRM_STATE_ERROR,
247 	XFRM_STATE_EXPIRED,
248 	XFRM_STATE_DEAD
249 };
250 
251 /* callback structure passed from either netlink or pfkey */
252 struct km_event {
253 	union {
254 		u32 hard;
255 		u32 proto;
256 		u32 byid;
257 		u32 aevent;
258 		u32 type;
259 	} data;
260 
261 	u32	seq;
262 	u32	pid;
263 	u32	event;
264 	struct net *net;
265 };
266 
267 struct xfrm_replay {
268 	void	(*advance)(struct xfrm_state *x, __be32 net_seq);
269 	int	(*check)(struct xfrm_state *x,
270 			 struct sk_buff *skb,
271 			 __be32 net_seq);
272 	void	(*notify)(struct xfrm_state *x, int event);
273 	int	(*overflow)(struct xfrm_state *x, struct sk_buff *skb);
274 };
275 
276 struct net_device;
277 struct xfrm_type;
278 struct xfrm_dst;
279 struct xfrm_policy_afinfo {
280 	unsigned short		family;
281 	struct dst_ops		*dst_ops;
282 	void			(*garbage_collect)(struct net *net);
283 	struct dst_entry	*(*dst_lookup)(struct net *net, int tos,
284 					       const xfrm_address_t *saddr,
285 					       const xfrm_address_t *daddr);
286 	int			(*get_saddr)(struct net *net, xfrm_address_t *saddr, xfrm_address_t *daddr);
287 	void			(*decode_session)(struct sk_buff *skb,
288 						  struct flowi *fl,
289 						  int reverse);
290 	int			(*get_tos)(const struct flowi *fl);
291 	int			(*init_path)(struct xfrm_dst *path,
292 					     struct dst_entry *dst,
293 					     int nfheader_len);
294 	int			(*fill_dst)(struct xfrm_dst *xdst,
295 					    struct net_device *dev,
296 					    const struct flowi *fl);
297 	struct dst_entry	*(*blackhole_route)(struct net *net, struct dst_entry *orig);
298 };
299 
300 extern int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
301 extern int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
302 extern void km_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c);
303 extern void km_state_notify(struct xfrm_state *x, const struct km_event *c);
304 
305 struct xfrm_tmpl;
306 extern int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol);
307 extern void km_state_expired(struct xfrm_state *x, int hard, u32 pid);
308 extern int __xfrm_state_delete(struct xfrm_state *x);
309 
310 struct xfrm_state_afinfo {
311 	unsigned int		family;
312 	unsigned int		proto;
313 	__be16			eth_proto;
314 	struct module		*owner;
315 	const struct xfrm_type	*type_map[IPPROTO_MAX];
316 	struct xfrm_mode	*mode_map[XFRM_MODE_MAX];
317 	int			(*init_flags)(struct xfrm_state *x);
318 	void			(*init_tempsel)(struct xfrm_selector *sel,
319 						const struct flowi *fl);
320 	void			(*init_temprop)(struct xfrm_state *x,
321 						const struct xfrm_tmpl *tmpl,
322 						const xfrm_address_t *daddr,
323 						const xfrm_address_t *saddr);
324 	int			(*tmpl_sort)(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n);
325 	int			(*state_sort)(struct xfrm_state **dst, struct xfrm_state **src, int n);
326 	int			(*output)(struct sk_buff *skb);
327 	int			(*output_finish)(struct sk_buff *skb);
328 	int			(*extract_input)(struct xfrm_state *x,
329 						 struct sk_buff *skb);
330 	int			(*extract_output)(struct xfrm_state *x,
331 						  struct sk_buff *skb);
332 	int			(*transport_finish)(struct sk_buff *skb,
333 						    int async);
334 };
335 
336 extern int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo);
337 extern int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo);
338 
339 extern void xfrm_state_delete_tunnel(struct xfrm_state *x);
340 
341 struct xfrm_type {
342 	char			*description;
343 	struct module		*owner;
344 	u8			proto;
345 	u8			flags;
346 #define XFRM_TYPE_NON_FRAGMENT	1
347 #define XFRM_TYPE_REPLAY_PROT	2
348 #define XFRM_TYPE_LOCAL_COADDR	4
349 #define XFRM_TYPE_REMOTE_COADDR	8
350 
351 	int			(*init_state)(struct xfrm_state *x);
352 	void			(*destructor)(struct xfrm_state *);
353 	int			(*input)(struct xfrm_state *, struct sk_buff *skb);
354 	int			(*output)(struct xfrm_state *, struct sk_buff *pskb);
355 	int			(*reject)(struct xfrm_state *, struct sk_buff *,
356 					  const struct flowi *);
357 	int			(*hdr_offset)(struct xfrm_state *, struct sk_buff *, u8 **);
358 	/* Estimate maximal size of result of transformation of a dgram */
359 	u32			(*get_mtu)(struct xfrm_state *, int size);
360 };
361 
362 extern int xfrm_register_type(const struct xfrm_type *type, unsigned short family);
363 extern int xfrm_unregister_type(const struct xfrm_type *type, unsigned short family);
364 
365 struct xfrm_mode {
366 	/*
367 	 * Remove encapsulation header.
368 	 *
369 	 * The IP header will be moved over the top of the encapsulation
370 	 * header.
371 	 *
372 	 * On entry, the transport header shall point to where the IP header
373 	 * should be and the network header shall be set to where the IP
374 	 * header currently is.  skb->data shall point to the start of the
375 	 * payload.
376 	 */
377 	int (*input2)(struct xfrm_state *x, struct sk_buff *skb);
378 
379 	/*
380 	 * This is the actual input entry point.
381 	 *
382 	 * For transport mode and equivalent this would be identical to
383 	 * input2 (which does not need to be set).  While tunnel mode
384 	 * and equivalent would set this to the tunnel encapsulation function
385 	 * xfrm4_prepare_input that would in turn call input2.
386 	 */
387 	int (*input)(struct xfrm_state *x, struct sk_buff *skb);
388 
389 	/*
390 	 * Add encapsulation header.
391 	 *
392 	 * On exit, the transport header will be set to the start of the
393 	 * encapsulation header to be filled in by x->type->output and
394 	 * the mac header will be set to the nextheader (protocol for
395 	 * IPv4) field of the extension header directly preceding the
396 	 * encapsulation header, or in its absence, that of the top IP
397 	 * header.  The value of the network header will always point
398 	 * to the top IP header while skb->data will point to the payload.
399 	 */
400 	int (*output2)(struct xfrm_state *x,struct sk_buff *skb);
401 
402 	/*
403 	 * This is the actual output entry point.
404 	 *
405 	 * For transport mode and equivalent this would be identical to
406 	 * output2 (which does not need to be set).  While tunnel mode
407 	 * and equivalent would set this to a tunnel encapsulation function
408 	 * (xfrm4_prepare_output or xfrm6_prepare_output) that would in turn
409 	 * call output2.
410 	 */
411 	int (*output)(struct xfrm_state *x, struct sk_buff *skb);
412 
413 	struct xfrm_state_afinfo *afinfo;
414 	struct module *owner;
415 	unsigned int encap;
416 	int flags;
417 };
418 
419 /* Flags for xfrm_mode. */
420 enum {
421 	XFRM_MODE_FLAG_TUNNEL = 1,
422 };
423 
424 extern int xfrm_register_mode(struct xfrm_mode *mode, int family);
425 extern int xfrm_unregister_mode(struct xfrm_mode *mode, int family);
426 
427 static inline int xfrm_af2proto(unsigned int family)
428 {
429 	switch(family) {
430 	case AF_INET:
431 		return IPPROTO_IPIP;
432 	case AF_INET6:
433 		return IPPROTO_IPV6;
434 	default:
435 		return 0;
436 	}
437 }
438 
439 static inline struct xfrm_mode *xfrm_ip2inner_mode(struct xfrm_state *x, int ipproto)
440 {
441 	if ((ipproto == IPPROTO_IPIP && x->props.family == AF_INET) ||
442 	    (ipproto == IPPROTO_IPV6 && x->props.family == AF_INET6))
443 		return x->inner_mode;
444 	else
445 		return x->inner_mode_iaf;
446 }
447 
448 struct xfrm_tmpl {
449 /* id in template is interpreted as:
450  * daddr - destination of tunnel, may be zero for transport mode.
451  * spi   - zero to acquire spi. Not zero if spi is static, then
452  *	   daddr must be fixed too.
453  * proto - AH/ESP/IPCOMP
454  */
455 	struct xfrm_id		id;
456 
457 /* Source address of tunnel. Ignored, if it is not a tunnel. */
458 	xfrm_address_t		saddr;
459 
460 	unsigned short		encap_family;
461 
462 	u32			reqid;
463 
464 /* Mode: transport, tunnel etc. */
465 	u8			mode;
466 
467 /* Sharing mode: unique, this session only, this user only etc. */
468 	u8			share;
469 
470 /* May skip this transfomration if no SA is found */
471 	u8			optional;
472 
473 /* Skip aalgos/ealgos/calgos checks. */
474 	u8			allalgs;
475 
476 /* Bit mask of algos allowed for acquisition */
477 	u32			aalgos;
478 	u32			ealgos;
479 	u32			calgos;
480 };
481 
482 #define XFRM_MAX_DEPTH		6
483 
484 struct xfrm_policy_walk_entry {
485 	struct list_head	all;
486 	u8			dead;
487 };
488 
489 struct xfrm_policy_walk {
490 	struct xfrm_policy_walk_entry walk;
491 	u8 type;
492 	u32 seq;
493 };
494 
495 struct xfrm_policy {
496 #ifdef CONFIG_NET_NS
497 	struct net		*xp_net;
498 #endif
499 	struct hlist_node	bydst;
500 	struct hlist_node	byidx;
501 
502 	/* This lock only affects elements except for entry. */
503 	rwlock_t		lock;
504 	atomic_t		refcnt;
505 	struct timer_list	timer;
506 
507 	struct flow_cache_object flo;
508 	atomic_t		genid;
509 	u32			priority;
510 	u32			index;
511 	struct xfrm_mark	mark;
512 	struct xfrm_selector	selector;
513 	struct xfrm_lifetime_cfg lft;
514 	struct xfrm_lifetime_cur curlft;
515 	struct xfrm_policy_walk_entry walk;
516 	u8			type;
517 	u8			action;
518 	u8			flags;
519 	u8			xfrm_nr;
520 	u16			family;
521 	struct xfrm_sec_ctx	*security;
522 	struct xfrm_tmpl       	xfrm_vec[XFRM_MAX_DEPTH];
523 };
524 
525 static inline struct net *xp_net(const struct xfrm_policy *xp)
526 {
527 	return read_pnet(&xp->xp_net);
528 }
529 
530 struct xfrm_kmaddress {
531 	xfrm_address_t          local;
532 	xfrm_address_t          remote;
533 	u32			reserved;
534 	u16			family;
535 };
536 
537 struct xfrm_migrate {
538 	xfrm_address_t		old_daddr;
539 	xfrm_address_t		old_saddr;
540 	xfrm_address_t		new_daddr;
541 	xfrm_address_t		new_saddr;
542 	u8			proto;
543 	u8			mode;
544 	u16			reserved;
545 	u32			reqid;
546 	u16			old_family;
547 	u16			new_family;
548 };
549 
550 #define XFRM_KM_TIMEOUT                30
551 /* which seqno */
552 #define XFRM_REPLAY_SEQ		1
553 #define XFRM_REPLAY_OSEQ	2
554 #define XFRM_REPLAY_SEQ_MASK	3
555 /* what happened */
556 #define XFRM_REPLAY_UPDATE	XFRM_AE_CR
557 #define XFRM_REPLAY_TIMEOUT	XFRM_AE_CE
558 
559 /* default aevent timeout in units of 100ms */
560 #define XFRM_AE_ETIME			10
561 /* Async Event timer multiplier */
562 #define XFRM_AE_ETH_M			10
563 /* default seq threshold size */
564 #define XFRM_AE_SEQT_SIZE		2
565 
566 struct xfrm_mgr {
567 	struct list_head	list;
568 	char			*id;
569 	int			(*notify)(struct xfrm_state *x, const struct km_event *c);
570 	int			(*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
571 	struct xfrm_policy	*(*compile_policy)(struct sock *sk, int opt, u8 *data, int len, int *dir);
572 	int			(*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
573 	int			(*notify_policy)(struct xfrm_policy *x, int dir, const struct km_event *c);
574 	int			(*report)(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
575 	int			(*migrate)(const struct xfrm_selector *sel,
576 					   u8 dir, u8 type,
577 					   const struct xfrm_migrate *m,
578 					   int num_bundles,
579 					   const struct xfrm_kmaddress *k);
580 };
581 
582 extern int xfrm_register_km(struct xfrm_mgr *km);
583 extern int xfrm_unregister_km(struct xfrm_mgr *km);
584 
585 /*
586  * This structure is used for the duration where packets are being
587  * transformed by IPsec.  As soon as the packet leaves IPsec the
588  * area beyond the generic IP part may be overwritten.
589  */
590 struct xfrm_skb_cb {
591 	union {
592 		struct inet_skb_parm h4;
593 		struct inet6_skb_parm h6;
594         } header;
595 
596         /* Sequence number for replay protection. */
597 	union {
598 		struct {
599 			__u32 low;
600 			__u32 hi;
601 		} output;
602 		struct {
603 			__be32 low;
604 			__be32 hi;
605 		} input;
606 	} seq;
607 };
608 
609 #define XFRM_SKB_CB(__skb) ((struct xfrm_skb_cb *)&((__skb)->cb[0]))
610 
611 /*
612  * This structure is used by the afinfo prepare_input/prepare_output functions
613  * to transmit header information to the mode input/output functions.
614  */
615 struct xfrm_mode_skb_cb {
616 	union {
617 		struct inet_skb_parm h4;
618 		struct inet6_skb_parm h6;
619 	} header;
620 
621 	/* Copied from header for IPv4, always set to zero and DF for IPv6. */
622 	__be16 id;
623 	__be16 frag_off;
624 
625 	/* IP header length (excluding options or extension headers). */
626 	u8 ihl;
627 
628 	/* TOS for IPv4, class for IPv6. */
629 	u8 tos;
630 
631 	/* TTL for IPv4, hop limitfor IPv6. */
632 	u8 ttl;
633 
634 	/* Protocol for IPv4, NH for IPv6. */
635 	u8 protocol;
636 
637 	/* Option length for IPv4, zero for IPv6. */
638 	u8 optlen;
639 
640 	/* Used by IPv6 only, zero for IPv4. */
641 	u8 flow_lbl[3];
642 };
643 
644 #define XFRM_MODE_SKB_CB(__skb) ((struct xfrm_mode_skb_cb *)&((__skb)->cb[0]))
645 
646 /*
647  * This structure is used by the input processing to locate the SPI and
648  * related information.
649  */
650 struct xfrm_spi_skb_cb {
651 	union {
652 		struct inet_skb_parm h4;
653 		struct inet6_skb_parm h6;
654 	} header;
655 
656 	unsigned int daddroff;
657 	unsigned int family;
658 };
659 
660 #define XFRM_SPI_SKB_CB(__skb) ((struct xfrm_spi_skb_cb *)&((__skb)->cb[0]))
661 
662 /* Audit Information */
663 struct xfrm_audit {
664 	u32	secid;
665 	uid_t	loginuid;
666 	u32	sessionid;
667 };
668 
669 #ifdef CONFIG_AUDITSYSCALL
670 static inline struct audit_buffer *xfrm_audit_start(const char *op)
671 {
672 	struct audit_buffer *audit_buf = NULL;
673 
674 	if (audit_enabled == 0)
675 		return NULL;
676 	audit_buf = audit_log_start(current->audit_context, GFP_ATOMIC,
677 				    AUDIT_MAC_IPSEC_EVENT);
678 	if (audit_buf == NULL)
679 		return NULL;
680 	audit_log_format(audit_buf, "op=%s", op);
681 	return audit_buf;
682 }
683 
684 static inline void xfrm_audit_helper_usrinfo(uid_t auid, u32 ses, u32 secid,
685 					     struct audit_buffer *audit_buf)
686 {
687 	char *secctx;
688 	u32 secctx_len;
689 
690 	audit_log_format(audit_buf, " auid=%u ses=%u", auid, ses);
691 	if (secid != 0 &&
692 	    security_secid_to_secctx(secid, &secctx, &secctx_len) == 0) {
693 		audit_log_format(audit_buf, " subj=%s", secctx);
694 		security_release_secctx(secctx, secctx_len);
695 	} else
696 		audit_log_task_context(audit_buf);
697 }
698 
699 extern void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
700 				  u32 auid, u32 ses, u32 secid);
701 extern void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
702 				  u32 auid, u32 ses, u32 secid);
703 extern void xfrm_audit_state_add(struct xfrm_state *x, int result,
704 				 u32 auid, u32 ses, u32 secid);
705 extern void xfrm_audit_state_delete(struct xfrm_state *x, int result,
706 				    u32 auid, u32 ses, u32 secid);
707 extern void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
708 					     struct sk_buff *skb);
709 extern void xfrm_audit_state_replay(struct xfrm_state *x,
710 				    struct sk_buff *skb, __be32 net_seq);
711 extern void xfrm_audit_state_notfound_simple(struct sk_buff *skb, u16 family);
712 extern void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
713 				      __be32 net_spi, __be32 net_seq);
714 extern void xfrm_audit_state_icvfail(struct xfrm_state *x,
715 				     struct sk_buff *skb, u8 proto);
716 #else
717 
718 static inline void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
719 				  u32 auid, u32 ses, u32 secid)
720 {
721 }
722 
723 static inline void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
724 				  u32 auid, u32 ses, u32 secid)
725 {
726 }
727 
728 static inline void xfrm_audit_state_add(struct xfrm_state *x, int result,
729 				 u32 auid, u32 ses, u32 secid)
730 {
731 }
732 
733 static inline void xfrm_audit_state_delete(struct xfrm_state *x, int result,
734 				    u32 auid, u32 ses, u32 secid)
735 {
736 }
737 
738 static inline void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
739 					     struct sk_buff *skb)
740 {
741 }
742 
743 static inline void xfrm_audit_state_replay(struct xfrm_state *x,
744 					   struct sk_buff *skb, __be32 net_seq)
745 {
746 }
747 
748 static inline void xfrm_audit_state_notfound_simple(struct sk_buff *skb,
749 				      u16 family)
750 {
751 }
752 
753 static inline void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
754 				      __be32 net_spi, __be32 net_seq)
755 {
756 }
757 
758 static inline void xfrm_audit_state_icvfail(struct xfrm_state *x,
759 				     struct sk_buff *skb, u8 proto)
760 {
761 }
762 #endif /* CONFIG_AUDITSYSCALL */
763 
764 static inline void xfrm_pol_hold(struct xfrm_policy *policy)
765 {
766 	if (likely(policy != NULL))
767 		atomic_inc(&policy->refcnt);
768 }
769 
770 extern void xfrm_policy_destroy(struct xfrm_policy *policy);
771 
772 static inline void xfrm_pol_put(struct xfrm_policy *policy)
773 {
774 	if (atomic_dec_and_test(&policy->refcnt))
775 		xfrm_policy_destroy(policy);
776 }
777 
778 static inline void xfrm_pols_put(struct xfrm_policy **pols, int npols)
779 {
780 	int i;
781 	for (i = npols - 1; i >= 0; --i)
782 		xfrm_pol_put(pols[i]);
783 }
784 
785 extern void __xfrm_state_destroy(struct xfrm_state *);
786 
787 static inline void __xfrm_state_put(struct xfrm_state *x)
788 {
789 	atomic_dec(&x->refcnt);
790 }
791 
792 static inline void xfrm_state_put(struct xfrm_state *x)
793 {
794 	if (atomic_dec_and_test(&x->refcnt))
795 		__xfrm_state_destroy(x);
796 }
797 
798 static inline void xfrm_state_hold(struct xfrm_state *x)
799 {
800 	atomic_inc(&x->refcnt);
801 }
802 
803 static inline bool addr_match(const void *token1, const void *token2,
804 			      int prefixlen)
805 {
806 	const __be32 *a1 = token1;
807 	const __be32 *a2 = token2;
808 	int pdw;
809 	int pbi;
810 
811 	pdw = prefixlen >> 5;	  /* num of whole u32 in prefix */
812 	pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
813 
814 	if (pdw)
815 		if (memcmp(a1, a2, pdw << 2))
816 			return false;
817 
818 	if (pbi) {
819 		__be32 mask;
820 
821 		mask = htonl((0xffffffff) << (32 - pbi));
822 
823 		if ((a1[pdw] ^ a2[pdw]) & mask)
824 			return false;
825 	}
826 
827 	return true;
828 }
829 
830 static __inline__
831 __be16 xfrm_flowi_sport(const struct flowi *fl, const union flowi_uli *uli)
832 {
833 	__be16 port;
834 	switch(fl->flowi_proto) {
835 	case IPPROTO_TCP:
836 	case IPPROTO_UDP:
837 	case IPPROTO_UDPLITE:
838 	case IPPROTO_SCTP:
839 		port = uli->ports.sport;
840 		break;
841 	case IPPROTO_ICMP:
842 	case IPPROTO_ICMPV6:
843 		port = htons(uli->icmpt.type);
844 		break;
845 	case IPPROTO_MH:
846 		port = htons(uli->mht.type);
847 		break;
848 	case IPPROTO_GRE:
849 		port = htons(ntohl(uli->gre_key) >> 16);
850 		break;
851 	default:
852 		port = 0;	/*XXX*/
853 	}
854 	return port;
855 }
856 
857 static __inline__
858 __be16 xfrm_flowi_dport(const struct flowi *fl, const union flowi_uli *uli)
859 {
860 	__be16 port;
861 	switch(fl->flowi_proto) {
862 	case IPPROTO_TCP:
863 	case IPPROTO_UDP:
864 	case IPPROTO_UDPLITE:
865 	case IPPROTO_SCTP:
866 		port = uli->ports.dport;
867 		break;
868 	case IPPROTO_ICMP:
869 	case IPPROTO_ICMPV6:
870 		port = htons(uli->icmpt.code);
871 		break;
872 	case IPPROTO_GRE:
873 		port = htons(ntohl(uli->gre_key) & 0xffff);
874 		break;
875 	default:
876 		port = 0;	/*XXX*/
877 	}
878 	return port;
879 }
880 
881 extern int xfrm_selector_match(const struct xfrm_selector *sel,
882 			       const struct flowi *fl,
883 			       unsigned short family);
884 
885 #ifdef CONFIG_SECURITY_NETWORK_XFRM
886 /*	If neither has a context --> match
887  * 	Otherwise, both must have a context and the sids, doi, alg must match
888  */
889 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
890 {
891 	return ((!s1 && !s2) ||
892 		(s1 && s2 &&
893 		 (s1->ctx_sid == s2->ctx_sid) &&
894 		 (s1->ctx_doi == s2->ctx_doi) &&
895 		 (s1->ctx_alg == s2->ctx_alg)));
896 }
897 #else
898 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
899 {
900 	return 1;
901 }
902 #endif
903 
904 /* A struct encoding bundle of transformations to apply to some set of flow.
905  *
906  * dst->child points to the next element of bundle.
907  * dst->xfrm  points to an instanse of transformer.
908  *
909  * Due to unfortunate limitations of current routing cache, which we
910  * have no time to fix, it mirrors struct rtable and bound to the same
911  * routing key, including saddr,daddr. However, we can have many of
912  * bundles differing by session id. All the bundles grow from a parent
913  * policy rule.
914  */
915 struct xfrm_dst {
916 	union {
917 		struct dst_entry	dst;
918 		struct rtable		rt;
919 		struct rt6_info		rt6;
920 	} u;
921 	struct dst_entry *route;
922 	struct flow_cache_object flo;
923 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
924 	int num_pols, num_xfrms;
925 #ifdef CONFIG_XFRM_SUB_POLICY
926 	struct flowi *origin;
927 	struct xfrm_selector *partner;
928 #endif
929 	u32 xfrm_genid;
930 	u32 policy_genid;
931 	u32 route_mtu_cached;
932 	u32 child_mtu_cached;
933 	u32 route_cookie;
934 	u32 path_cookie;
935 };
936 
937 #ifdef CONFIG_XFRM
938 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
939 {
940 	xfrm_pols_put(xdst->pols, xdst->num_pols);
941 	dst_release(xdst->route);
942 	if (likely(xdst->u.dst.xfrm))
943 		xfrm_state_put(xdst->u.dst.xfrm);
944 #ifdef CONFIG_XFRM_SUB_POLICY
945 	kfree(xdst->origin);
946 	xdst->origin = NULL;
947 	kfree(xdst->partner);
948 	xdst->partner = NULL;
949 #endif
950 }
951 #endif
952 
953 extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
954 
955 struct sec_path {
956 	atomic_t		refcnt;
957 	int			len;
958 	struct xfrm_state	*xvec[XFRM_MAX_DEPTH];
959 };
960 
961 static inline int secpath_exists(struct sk_buff *skb)
962 {
963 #ifdef CONFIG_XFRM
964 	return skb->sp != NULL;
965 #else
966 	return 0;
967 #endif
968 }
969 
970 static inline struct sec_path *
971 secpath_get(struct sec_path *sp)
972 {
973 	if (sp)
974 		atomic_inc(&sp->refcnt);
975 	return sp;
976 }
977 
978 extern void __secpath_destroy(struct sec_path *sp);
979 
980 static inline void
981 secpath_put(struct sec_path *sp)
982 {
983 	if (sp && atomic_dec_and_test(&sp->refcnt))
984 		__secpath_destroy(sp);
985 }
986 
987 extern struct sec_path *secpath_dup(struct sec_path *src);
988 
989 static inline void
990 secpath_reset(struct sk_buff *skb)
991 {
992 #ifdef CONFIG_XFRM
993 	secpath_put(skb->sp);
994 	skb->sp = NULL;
995 #endif
996 }
997 
998 static inline int
999 xfrm_addr_any(const xfrm_address_t *addr, unsigned short family)
1000 {
1001 	switch (family) {
1002 	case AF_INET:
1003 		return addr->a4 == 0;
1004 	case AF_INET6:
1005 		return ipv6_addr_any((struct in6_addr *)&addr->a6);
1006 	}
1007 	return 0;
1008 }
1009 
1010 static inline int
1011 __xfrm4_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1012 {
1013 	return	(tmpl->saddr.a4 &&
1014 		 tmpl->saddr.a4 != x->props.saddr.a4);
1015 }
1016 
1017 static inline int
1018 __xfrm6_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1019 {
1020 	return	(!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
1021 		 ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
1022 }
1023 
1024 static inline int
1025 xfrm_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, unsigned short family)
1026 {
1027 	switch (family) {
1028 	case AF_INET:
1029 		return __xfrm4_state_addr_cmp(tmpl, x);
1030 	case AF_INET6:
1031 		return __xfrm6_state_addr_cmp(tmpl, x);
1032 	}
1033 	return !0;
1034 }
1035 
1036 #ifdef CONFIG_XFRM
1037 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
1038 
1039 static inline int __xfrm_policy_check2(struct sock *sk, int dir,
1040 				       struct sk_buff *skb,
1041 				       unsigned int family, int reverse)
1042 {
1043 	struct net *net = dev_net(skb->dev);
1044 	int ndir = dir | (reverse ? XFRM_POLICY_MASK + 1 : 0);
1045 
1046 	if (sk && sk->sk_policy[XFRM_POLICY_IN])
1047 		return __xfrm_policy_check(sk, ndir, skb, family);
1048 
1049 	return	(!net->xfrm.policy_count[dir] && !skb->sp) ||
1050 		(skb_dst(skb)->flags & DST_NOPOLICY) ||
1051 		__xfrm_policy_check(sk, ndir, skb, family);
1052 }
1053 
1054 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1055 {
1056 	return __xfrm_policy_check2(sk, dir, skb, family, 0);
1057 }
1058 
1059 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1060 {
1061 	return xfrm_policy_check(sk, dir, skb, AF_INET);
1062 }
1063 
1064 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1065 {
1066 	return xfrm_policy_check(sk, dir, skb, AF_INET6);
1067 }
1068 
1069 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1070 					     struct sk_buff *skb)
1071 {
1072 	return __xfrm_policy_check2(sk, dir, skb, AF_INET, 1);
1073 }
1074 
1075 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1076 					     struct sk_buff *skb)
1077 {
1078 	return __xfrm_policy_check2(sk, dir, skb, AF_INET6, 1);
1079 }
1080 
1081 extern int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1082 				 unsigned int family, int reverse);
1083 
1084 static inline int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1085 				      unsigned int family)
1086 {
1087 	return __xfrm_decode_session(skb, fl, family, 0);
1088 }
1089 
1090 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1091 					      struct flowi *fl,
1092 					      unsigned int family)
1093 {
1094 	return __xfrm_decode_session(skb, fl, family, 1);
1095 }
1096 
1097 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
1098 
1099 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1100 {
1101 	struct net *net = dev_net(skb->dev);
1102 
1103 	return	!net->xfrm.policy_count[XFRM_POLICY_OUT] ||
1104 		(skb_dst(skb)->flags & DST_NOXFRM) ||
1105 		__xfrm_route_forward(skb, family);
1106 }
1107 
1108 static inline int xfrm4_route_forward(struct sk_buff *skb)
1109 {
1110 	return xfrm_route_forward(skb, AF_INET);
1111 }
1112 
1113 static inline int xfrm6_route_forward(struct sk_buff *skb)
1114 {
1115 	return xfrm_route_forward(skb, AF_INET6);
1116 }
1117 
1118 extern int __xfrm_sk_clone_policy(struct sock *sk);
1119 
1120 static inline int xfrm_sk_clone_policy(struct sock *sk)
1121 {
1122 	if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
1123 		return __xfrm_sk_clone_policy(sk);
1124 	return 0;
1125 }
1126 
1127 extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);
1128 
1129 static inline void xfrm_sk_free_policy(struct sock *sk)
1130 {
1131 	if (unlikely(sk->sk_policy[0] != NULL)) {
1132 		xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
1133 		sk->sk_policy[0] = NULL;
1134 	}
1135 	if (unlikely(sk->sk_policy[1] != NULL)) {
1136 		xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
1137 		sk->sk_policy[1] = NULL;
1138 	}
1139 }
1140 
1141 #else
1142 
1143 static inline void xfrm_sk_free_policy(struct sock *sk) {}
1144 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
1145 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
1146 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
1147 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1148 {
1149 	return 1;
1150 }
1151 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1152 {
1153 	return 1;
1154 }
1155 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1156 {
1157 	return 1;
1158 }
1159 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1160 					      struct flowi *fl,
1161 					      unsigned int family)
1162 {
1163 	return -ENOSYS;
1164 }
1165 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1166 					     struct sk_buff *skb)
1167 {
1168 	return 1;
1169 }
1170 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1171 					     struct sk_buff *skb)
1172 {
1173 	return 1;
1174 }
1175 #endif
1176 
1177 static __inline__
1178 xfrm_address_t *xfrm_flowi_daddr(const struct flowi *fl, unsigned short family)
1179 {
1180 	switch (family){
1181 	case AF_INET:
1182 		return (xfrm_address_t *)&fl->u.ip4.daddr;
1183 	case AF_INET6:
1184 		return (xfrm_address_t *)&fl->u.ip6.daddr;
1185 	}
1186 	return NULL;
1187 }
1188 
1189 static __inline__
1190 xfrm_address_t *xfrm_flowi_saddr(const struct flowi *fl, unsigned short family)
1191 {
1192 	switch (family){
1193 	case AF_INET:
1194 		return (xfrm_address_t *)&fl->u.ip4.saddr;
1195 	case AF_INET6:
1196 		return (xfrm_address_t *)&fl->u.ip6.saddr;
1197 	}
1198 	return NULL;
1199 }
1200 
1201 static __inline__
1202 void xfrm_flowi_addr_get(const struct flowi *fl,
1203 			 xfrm_address_t *saddr, xfrm_address_t *daddr,
1204 			 unsigned short family)
1205 {
1206 	switch(family) {
1207 	case AF_INET:
1208 		memcpy(&saddr->a4, &fl->u.ip4.saddr, sizeof(saddr->a4));
1209 		memcpy(&daddr->a4, &fl->u.ip4.daddr, sizeof(daddr->a4));
1210 		break;
1211 	case AF_INET6:
1212 		ipv6_addr_copy((struct in6_addr *)&saddr->a6, &fl->u.ip6.saddr);
1213 		ipv6_addr_copy((struct in6_addr *)&daddr->a6, &fl->u.ip6.daddr);
1214 		break;
1215 	}
1216 }
1217 
1218 static __inline__ int
1219 __xfrm4_state_addr_check(const struct xfrm_state *x,
1220 			 const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1221 {
1222 	if (daddr->a4 == x->id.daddr.a4 &&
1223 	    (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
1224 		return 1;
1225 	return 0;
1226 }
1227 
1228 static __inline__ int
1229 __xfrm6_state_addr_check(const struct xfrm_state *x,
1230 			 const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1231 {
1232 	if (!ipv6_addr_cmp((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
1233 	    (!ipv6_addr_cmp((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr)||
1234 	     ipv6_addr_any((struct in6_addr *)saddr) ||
1235 	     ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
1236 		return 1;
1237 	return 0;
1238 }
1239 
1240 static __inline__ int
1241 xfrm_state_addr_check(const struct xfrm_state *x,
1242 		      const xfrm_address_t *daddr, const xfrm_address_t *saddr,
1243 		      unsigned short family)
1244 {
1245 	switch (family) {
1246 	case AF_INET:
1247 		return __xfrm4_state_addr_check(x, daddr, saddr);
1248 	case AF_INET6:
1249 		return __xfrm6_state_addr_check(x, daddr, saddr);
1250 	}
1251 	return 0;
1252 }
1253 
1254 static __inline__ int
1255 xfrm_state_addr_flow_check(const struct xfrm_state *x, const struct flowi *fl,
1256 			   unsigned short family)
1257 {
1258 	switch (family) {
1259 	case AF_INET:
1260 		return __xfrm4_state_addr_check(x,
1261 						(const xfrm_address_t *)&fl->u.ip4.daddr,
1262 						(const xfrm_address_t *)&fl->u.ip4.saddr);
1263 	case AF_INET6:
1264 		return __xfrm6_state_addr_check(x,
1265 						(const xfrm_address_t *)&fl->u.ip6.daddr,
1266 						(const xfrm_address_t *)&fl->u.ip6.saddr);
1267 	}
1268 	return 0;
1269 }
1270 
1271 static inline int xfrm_state_kern(const struct xfrm_state *x)
1272 {
1273 	return atomic_read(&x->tunnel_users);
1274 }
1275 
1276 static inline int xfrm_id_proto_match(u8 proto, u8 userproto)
1277 {
1278 	return (!userproto || proto == userproto ||
1279 		(userproto == IPSEC_PROTO_ANY && (proto == IPPROTO_AH ||
1280 						  proto == IPPROTO_ESP ||
1281 						  proto == IPPROTO_COMP)));
1282 }
1283 
1284 /*
1285  * xfrm algorithm information
1286  */
1287 struct xfrm_algo_aead_info {
1288 	u16 icv_truncbits;
1289 };
1290 
1291 struct xfrm_algo_auth_info {
1292 	u16 icv_truncbits;
1293 	u16 icv_fullbits;
1294 };
1295 
1296 struct xfrm_algo_encr_info {
1297 	u16 blockbits;
1298 	u16 defkeybits;
1299 };
1300 
1301 struct xfrm_algo_comp_info {
1302 	u16 threshold;
1303 };
1304 
1305 struct xfrm_algo_desc {
1306 	char *name;
1307 	char *compat;
1308 	u8 available:1;
1309 	union {
1310 		struct xfrm_algo_aead_info aead;
1311 		struct xfrm_algo_auth_info auth;
1312 		struct xfrm_algo_encr_info encr;
1313 		struct xfrm_algo_comp_info comp;
1314 	} uinfo;
1315 	struct sadb_alg desc;
1316 };
1317 
1318 /* XFRM tunnel handlers.  */
1319 struct xfrm_tunnel {
1320 	int (*handler)(struct sk_buff *skb);
1321 	int (*err_handler)(struct sk_buff *skb, u32 info);
1322 
1323 	struct xfrm_tunnel __rcu *next;
1324 	int priority;
1325 };
1326 
1327 struct xfrm6_tunnel {
1328 	int (*handler)(struct sk_buff *skb);
1329 	int (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
1330 			   u8 type, u8 code, int offset, __be32 info);
1331 	struct xfrm6_tunnel __rcu *next;
1332 	int priority;
1333 };
1334 
1335 extern void xfrm_init(void);
1336 extern void xfrm4_init(int rt_hash_size);
1337 extern int xfrm_state_init(struct net *net);
1338 extern void xfrm_state_fini(struct net *net);
1339 extern void xfrm4_state_init(void);
1340 #ifdef CONFIG_XFRM
1341 extern int xfrm6_init(void);
1342 extern void xfrm6_fini(void);
1343 extern int xfrm6_state_init(void);
1344 extern void xfrm6_state_fini(void);
1345 #else
1346 static inline int xfrm6_init(void)
1347 {
1348 	return 0;
1349 }
1350 static inline void xfrm6_fini(void)
1351 {
1352 	;
1353 }
1354 #endif
1355 
1356 #ifdef CONFIG_XFRM_STATISTICS
1357 extern int xfrm_proc_init(struct net *net);
1358 extern void xfrm_proc_fini(struct net *net);
1359 #endif
1360 
1361 extern int xfrm_sysctl_init(struct net *net);
1362 #ifdef CONFIG_SYSCTL
1363 extern void xfrm_sysctl_fini(struct net *net);
1364 #else
1365 static inline void xfrm_sysctl_fini(struct net *net)
1366 {
1367 }
1368 #endif
1369 
1370 extern void xfrm_state_walk_init(struct xfrm_state_walk *walk, u8 proto);
1371 extern int xfrm_state_walk(struct net *net, struct xfrm_state_walk *walk,
1372 			   int (*func)(struct xfrm_state *, int, void*), void *);
1373 extern void xfrm_state_walk_done(struct xfrm_state_walk *walk);
1374 extern struct xfrm_state *xfrm_state_alloc(struct net *net);
1375 extern struct xfrm_state *xfrm_state_find(const xfrm_address_t *daddr,
1376 					  const xfrm_address_t *saddr,
1377 					  const struct flowi *fl,
1378 					  struct xfrm_tmpl *tmpl,
1379 					  struct xfrm_policy *pol, int *err,
1380 					  unsigned short family);
1381 extern struct xfrm_state *xfrm_stateonly_find(struct net *net, u32 mark,
1382 					       xfrm_address_t *daddr,
1383 					       xfrm_address_t *saddr,
1384 					       unsigned short family,
1385 					       u8 mode, u8 proto, u32 reqid);
1386 extern int xfrm_state_check_expire(struct xfrm_state *x);
1387 extern void xfrm_state_insert(struct xfrm_state *x);
1388 extern int xfrm_state_add(struct xfrm_state *x);
1389 extern int xfrm_state_update(struct xfrm_state *x);
1390 extern struct xfrm_state *xfrm_state_lookup(struct net *net, u32 mark,
1391 					    const xfrm_address_t *daddr, __be32 spi,
1392 					    u8 proto, unsigned short family);
1393 extern struct xfrm_state *xfrm_state_lookup_byaddr(struct net *net, u32 mark,
1394 						   const xfrm_address_t *daddr,
1395 						   const xfrm_address_t *saddr,
1396 						   u8 proto,
1397 						   unsigned short family);
1398 #ifdef CONFIG_XFRM_SUB_POLICY
1399 extern int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1400 			  int n, unsigned short family);
1401 extern int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1402 			   int n, unsigned short family);
1403 #else
1404 static inline int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1405 				 int n, unsigned short family)
1406 {
1407 	return -ENOSYS;
1408 }
1409 
1410 static inline int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1411 				  int n, unsigned short family)
1412 {
1413 	return -ENOSYS;
1414 }
1415 #endif
1416 
1417 struct xfrmk_sadinfo {
1418 	u32 sadhcnt; /* current hash bkts */
1419 	u32 sadhmcnt; /* max allowed hash bkts */
1420 	u32 sadcnt; /* current running count */
1421 };
1422 
1423 struct xfrmk_spdinfo {
1424 	u32 incnt;
1425 	u32 outcnt;
1426 	u32 fwdcnt;
1427 	u32 inscnt;
1428 	u32 outscnt;
1429 	u32 fwdscnt;
1430 	u32 spdhcnt;
1431 	u32 spdhmcnt;
1432 };
1433 
1434 extern struct xfrm_state *xfrm_find_acq_byseq(struct net *net, u32 mark,
1435 					      u32 seq);
1436 extern int xfrm_state_delete(struct xfrm_state *x);
1437 extern int xfrm_state_flush(struct net *net, u8 proto, struct xfrm_audit *audit_info);
1438 extern void xfrm_sad_getinfo(struct net *net, struct xfrmk_sadinfo *si);
1439 extern void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si);
1440 extern u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq);
1441 extern int xfrm_init_replay(struct xfrm_state *x);
1442 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
1443 extern int __xfrm_init_state(struct xfrm_state *x, bool init_replay);
1444 extern int xfrm_init_state(struct xfrm_state *x);
1445 extern int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb);
1446 extern int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi,
1447 		      int encap_type);
1448 extern int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
1449 extern int xfrm_output_resume(struct sk_buff *skb, int err);
1450 extern int xfrm_output(struct sk_buff *skb);
1451 extern int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1452 extern int xfrm4_extract_header(struct sk_buff *skb);
1453 extern int xfrm4_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1454 extern int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi,
1455 			   int encap_type);
1456 extern int xfrm4_transport_finish(struct sk_buff *skb, int async);
1457 extern int xfrm4_rcv(struct sk_buff *skb);
1458 
1459 static inline int xfrm4_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
1460 {
1461 	return xfrm4_rcv_encap(skb, nexthdr, spi, 0);
1462 }
1463 
1464 extern int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1465 extern int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1466 extern int xfrm4_output(struct sk_buff *skb);
1467 extern int xfrm4_output_finish(struct sk_buff *skb);
1468 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family);
1469 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family);
1470 extern int xfrm6_extract_header(struct sk_buff *skb);
1471 extern int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1472 extern int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi);
1473 extern int xfrm6_transport_finish(struct sk_buff *skb, int async);
1474 extern int xfrm6_rcv(struct sk_buff *skb);
1475 extern int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
1476 			    xfrm_address_t *saddr, u8 proto);
1477 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family);
1478 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family);
1479 extern __be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr);
1480 extern __be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr);
1481 extern int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1482 extern int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1483 extern int xfrm6_output(struct sk_buff *skb);
1484 extern int xfrm6_output_finish(struct sk_buff *skb);
1485 extern int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
1486 				 u8 **prevhdr);
1487 
1488 #ifdef CONFIG_XFRM
1489 extern int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb);
1490 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
1491 #else
1492 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
1493 {
1494  	return -ENOPROTOOPT;
1495 }
1496 
1497 static inline int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
1498 {
1499  	/* should not happen */
1500  	kfree_skb(skb);
1501 	return 0;
1502 }
1503 #endif
1504 
1505 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp);
1506 
1507 extern void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type);
1508 extern int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1509 	int (*func)(struct xfrm_policy *, int, int, void*), void *);
1510 extern void xfrm_policy_walk_done(struct xfrm_policy_walk *walk);
1511 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
1512 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark,
1513 					  u8 type, int dir,
1514 					  struct xfrm_selector *sel,
1515 					  struct xfrm_sec_ctx *ctx, int delete,
1516 					  int *err);
1517 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8, int dir, u32 id, int delete, int *err);
1518 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info);
1519 u32 xfrm_get_acqseq(void);
1520 extern int xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
1521 struct xfrm_state *xfrm_find_acq(struct net *net, struct xfrm_mark *mark,
1522 				 u8 mode, u32 reqid, u8 proto,
1523 				 const xfrm_address_t *daddr,
1524 				 const xfrm_address_t *saddr, int create,
1525 				 unsigned short family);
1526 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
1527 
1528 #ifdef CONFIG_XFRM_MIGRATE
1529 extern int km_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1530 		      const struct xfrm_migrate *m, int num_bundles,
1531 		      const struct xfrm_kmaddress *k);
1532 extern struct xfrm_state * xfrm_migrate_state_find(struct xfrm_migrate *m);
1533 extern struct xfrm_state * xfrm_state_migrate(struct xfrm_state *x,
1534 					      struct xfrm_migrate *m);
1535 extern int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1536 			struct xfrm_migrate *m, int num_bundles,
1537 			struct xfrm_kmaddress *k);
1538 #endif
1539 
1540 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
1541 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard, u32 pid);
1542 extern int km_report(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
1543 
1544 extern void xfrm_input_init(void);
1545 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq);
1546 
1547 extern void xfrm_probe_algs(void);
1548 extern int xfrm_count_auth_supported(void);
1549 extern int xfrm_count_enc_supported(void);
1550 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
1551 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
1552 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
1553 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
1554 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
1555 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(const char *name, int probe);
1556 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(const char *name, int probe);
1557 extern struct xfrm_algo_desc *xfrm_calg_get_byname(const char *name, int probe);
1558 extern struct xfrm_algo_desc *xfrm_aead_get_byname(const char *name, int icv_len,
1559 						   int probe);
1560 
1561 struct hash_desc;
1562 struct scatterlist;
1563 typedef int (icv_update_fn_t)(struct hash_desc *, struct scatterlist *,
1564 			      unsigned int);
1565 
1566 static inline int xfrm_addr_cmp(const xfrm_address_t *a,
1567 				const xfrm_address_t *b,
1568 				int family)
1569 {
1570 	switch (family) {
1571 	default:
1572 	case AF_INET:
1573 		return (__force u32)a->a4 - (__force u32)b->a4;
1574 	case AF_INET6:
1575 		return ipv6_addr_cmp((const struct in6_addr *)a,
1576 				     (const struct in6_addr *)b);
1577 	}
1578 }
1579 
1580 static inline int xfrm_policy_id2dir(u32 index)
1581 {
1582 	return index & 7;
1583 }
1584 
1585 #ifdef CONFIG_XFRM
1586 static inline int xfrm_aevent_is_on(struct net *net)
1587 {
1588 	struct sock *nlsk;
1589 	int ret = 0;
1590 
1591 	rcu_read_lock();
1592 	nlsk = rcu_dereference(net->xfrm.nlsk);
1593 	if (nlsk)
1594 		ret = netlink_has_listeners(nlsk, XFRMNLGRP_AEVENTS);
1595 	rcu_read_unlock();
1596 	return ret;
1597 }
1598 #endif
1599 
1600 static inline int xfrm_alg_len(const struct xfrm_algo *alg)
1601 {
1602 	return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1603 }
1604 
1605 static inline int xfrm_alg_auth_len(const struct xfrm_algo_auth *alg)
1606 {
1607 	return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1608 }
1609 
1610 static inline int xfrm_replay_state_esn_len(struct xfrm_replay_state_esn *replay_esn)
1611 {
1612 	return sizeof(*replay_esn) + replay_esn->bmp_len * sizeof(__u32);
1613 }
1614 
1615 #ifdef CONFIG_XFRM_MIGRATE
1616 static inline int xfrm_replay_clone(struct xfrm_state *x,
1617 				     struct xfrm_state *orig)
1618 {
1619 	x->replay_esn = kzalloc(xfrm_replay_state_esn_len(orig->replay_esn),
1620 				GFP_KERNEL);
1621 	if (!x->replay_esn)
1622 		return -ENOMEM;
1623 
1624 	x->replay_esn->bmp_len = orig->replay_esn->bmp_len;
1625 	x->replay_esn->replay_window = orig->replay_esn->replay_window;
1626 
1627 	x->preplay_esn = kmemdup(x->replay_esn,
1628 				 xfrm_replay_state_esn_len(x->replay_esn),
1629 				 GFP_KERNEL);
1630 	if (!x->preplay_esn) {
1631 		kfree(x->replay_esn);
1632 		return -ENOMEM;
1633 	}
1634 
1635 	return 0;
1636 }
1637 
1638 static inline struct xfrm_algo *xfrm_algo_clone(struct xfrm_algo *orig)
1639 {
1640 	return kmemdup(orig, xfrm_alg_len(orig), GFP_KERNEL);
1641 }
1642 
1643 static inline struct xfrm_algo_auth *xfrm_algo_auth_clone(struct xfrm_algo_auth *orig)
1644 {
1645 	return kmemdup(orig, xfrm_alg_auth_len(orig), GFP_KERNEL);
1646 }
1647 
1648 static inline void xfrm_states_put(struct xfrm_state **states, int n)
1649 {
1650 	int i;
1651 	for (i = 0; i < n; i++)
1652 		xfrm_state_put(*(states + i));
1653 }
1654 
1655 static inline void xfrm_states_delete(struct xfrm_state **states, int n)
1656 {
1657 	int i;
1658 	for (i = 0; i < n; i++)
1659 		xfrm_state_delete(*(states + i));
1660 }
1661 #endif
1662 
1663 #ifdef CONFIG_XFRM
1664 static inline struct xfrm_state *xfrm_input_state(struct sk_buff *skb)
1665 {
1666 	return skb->sp->xvec[skb->sp->len - 1];
1667 }
1668 #endif
1669 
1670 static inline int xfrm_mark_get(struct nlattr **attrs, struct xfrm_mark *m)
1671 {
1672 	if (attrs[XFRMA_MARK])
1673 		memcpy(m, nla_data(attrs[XFRMA_MARK]), sizeof(struct xfrm_mark));
1674 	else
1675 		m->v = m->m = 0;
1676 
1677 	return m->v & m->m;
1678 }
1679 
1680 static inline int xfrm_mark_put(struct sk_buff *skb, const struct xfrm_mark *m)
1681 {
1682 	if (m->m | m->v)
1683 		NLA_PUT(skb, XFRMA_MARK, sizeof(struct xfrm_mark), m);
1684 	return 0;
1685 
1686 nla_put_failure:
1687 	return -1;
1688 }
1689 
1690 #endif	/* _NET_XFRM_H */
1691