xfrm.h

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/* which seqno */
#define XFRM_REPLAY_SEQ		1
#define XFRM_REPLAY_OSEQ	2
#define XFRM_REPLAY_SEQ_MASK	3
/* what happened */
#define XFRM_REPLAY_UPDATE	XFRM_AE_CR
#define XFRM_REPLAY_TIMEOUT	XFRM_AE_CE

/* default aevent timeout in units of 100ms */
#define XFRM_AE_ETIME			10
/* Async Event timer multiplier */
#define XFRM_AE_ETH_M			10
/* default seq threshold size */
#define XFRM_AE_SEQT_SIZE		2

struct xfrm_mgr
{
	struct list_head	list;
	char			*id;
	int			(*notify)(struct xfrm_state *x, struct km_event *c);
	int			(*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
	struct xfrm_policy	*(*compile_policy)(struct sock *sk, int opt, u8 *data, int len, int *dir);
	int			(*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
	int			(*notify_policy)(struct xfrm_policy *x, int dir, struct km_event *c);
	int			(*report)(u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
	int			(*migrate)(struct xfrm_selector *sel, u8 dir, u8 type, struct xfrm_migrate *m, int num_bundles);
};

extern int xfrm_register_km(struct xfrm_mgr *km);
extern int xfrm_unregister_km(struct xfrm_mgr *km);

extern unsigned int xfrm_policy_count[XFRM_POLICY_MAX*2];

/*
 * This structure is used for the duration where packets are being
 * transformed by IPsec.  As soon as the packet leaves IPsec the
 * area beyond the generic IP part may be overwritten.
 */
struct xfrm_skb_cb {
	union {
		struct inet_skb_parm h4;
		struct inet6_skb_parm h6;
        } header;

        /* Sequence number for replay protection. */
        u64 seq;
};

#define XFRM_SKB_CB(__skb) ((struct xfrm_skb_cb *)&((__skb)->cb[0]))

/* Audit Information */
struct xfrm_audit
{
	u32	loginuid;
	u32	secid;
};

#ifdef CONFIG_AUDITSYSCALL
static inline struct audit_buffer *xfrm_audit_start(u32 auid, u32 sid)
{
	struct audit_buffer *audit_buf = NULL;
	char *secctx;
	u32 secctx_len;

	audit_buf = audit_log_start(current->audit_context, GFP_ATOMIC,
			      AUDIT_MAC_IPSEC_EVENT);
	if (audit_buf == NULL)
		return NULL;

	audit_log_format(audit_buf, "auid=%u", auid);

	if (sid != 0 &&
	    security_secid_to_secctx(sid, &secctx, &secctx_len) == 0) {
		audit_log_format(audit_buf, " subj=%s", secctx);
		security_release_secctx(secctx, secctx_len);
	} else
		audit_log_task_context(audit_buf);
	return audit_buf;
}

extern void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
				  u32 auid, u32 sid);
extern void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
				  u32 auid, u32 sid);
extern void xfrm_audit_state_add(struct xfrm_state *x, int result,
				 u32 auid, u32 sid);
extern void xfrm_audit_state_delete(struct xfrm_state *x, int result,
				    u32 auid, u32 sid);
#else
#define xfrm_audit_policy_add(x, r, a, s)	do { ; } while (0)
#define xfrm_audit_policy_delete(x, r, a, s)	do { ; } while (0)
#define xfrm_audit_state_add(x, r, a, s)	do { ; } while (0)
#define xfrm_audit_state_delete(x, r, a, s)	do { ; } while (0)
#endif /* CONFIG_AUDITSYSCALL */

static inline void xfrm_pol_hold(struct xfrm_policy *policy)
{
	if (likely(policy != NULL))
		atomic_inc(&policy->refcnt);
}

extern void __xfrm_policy_destroy(struct xfrm_policy *policy);

static inline void xfrm_pol_put(struct xfrm_policy *policy)
{
	if (atomic_dec_and_test(&policy->refcnt))
		__xfrm_policy_destroy(policy);
}

#ifdef CONFIG_XFRM_SUB_POLICY
static inline void xfrm_pols_put(struct xfrm_policy **pols, int npols)
{
	int i;
	for (i = npols - 1; i >= 0; --i)
		xfrm_pol_put(pols[i]);
}
#else
static inline void xfrm_pols_put(struct xfrm_policy **pols, int npols)
{
	xfrm_pol_put(pols[0]);
}
#endif

extern void __xfrm_state_destroy(struct xfrm_state *);

static inline void __xfrm_state_put(struct xfrm_state *x)
{
	atomic_dec(&x->refcnt);
}

static inline void xfrm_state_put(struct xfrm_state *x)
{
	if (atomic_dec_and_test(&x->refcnt))
		__xfrm_state_destroy(x);
}

static inline void xfrm_state_hold(struct xfrm_state *x)
{
	atomic_inc(&x->refcnt);
}

static __inline__ int addr_match(void *token1, void *token2, int prefixlen)
{
	__be32 *a1 = token1;
	__be32 *a2 = token2;
	int pdw;
	int pbi;

	pdw = prefixlen >> 5;	  /* num of whole __u32 in prefix */
	pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */

	if (pdw)
		if (memcmp(a1, a2, pdw << 2))
			return 0;

	if (pbi) {
		__be32 mask;

		mask = htonl((0xffffffff) << (32 - pbi));

		if ((a1[pdw] ^ a2[pdw]) & mask)
			return 0;
	}

	return 1;
}

static __inline__
__be16 xfrm_flowi_sport(struct flowi *fl)
{
	__be16 port;
	switch(fl->proto) {
	case IPPROTO_TCP:
	case IPPROTO_UDP:
	case IPPROTO_UDPLITE:
	case IPPROTO_SCTP:
		port = fl->fl_ip_sport;
		break;
	case IPPROTO_ICMP:
	case IPPROTO_ICMPV6:
		port = htons(fl->fl_icmp_type);
		break;
	case IPPROTO_MH:
		port = htons(fl->fl_mh_type);
		break;
	default:
		port = 0;	/*XXX*/
	}
	return port;
}

static __inline__
__be16 xfrm_flowi_dport(struct flowi *fl)
{
	__be16 port;
	switch(fl->proto) {
	case IPPROTO_TCP:
	case IPPROTO_UDP:
	case IPPROTO_UDPLITE:
	case IPPROTO_SCTP:
		port = fl->fl_ip_dport;
		break;
	case IPPROTO_ICMP:
	case IPPROTO_ICMPV6:
		port = htons(fl->fl_icmp_code);
		break;
	default:
		port = 0;	/*XXX*/
	}
	return port;
}

extern int xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
			       unsigned short family);

#ifdef CONFIG_SECURITY_NETWORK_XFRM
/*	If neither has a context --> match
 * 	Otherwise, both must have a context and the sids, doi, alg must match
 */
static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
{
	return ((!s1 && !s2) ||
		(s1 && s2 &&
		 (s1->ctx_sid == s2->ctx_sid) &&
		 (s1->ctx_doi == s2->ctx_doi) &&
		 (s1->ctx_alg == s2->ctx_alg)));
}
#else
static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
{
	return 1;
}
#endif

/* A struct encoding bundle of transformations to apply to some set of flow.
 *
 * dst->child points to the next element of bundle.
 * dst->xfrm  points to an instanse of transformer.
 *
 * Due to unfortunate limitations of current routing cache, which we
 * have no time to fix, it mirrors struct rtable and bound to the same
 * routing key, including saddr,daddr. However, we can have many of
 * bundles differing by session id. All the bundles grow from a parent
 * policy rule.
 */
struct xfrm_dst
{
	union {
		struct dst_entry	dst;
		struct rtable		rt;
		struct rt6_info		rt6;
	} u;
	struct dst_entry *route;
#ifdef CONFIG_XFRM_SUB_POLICY
	struct flowi *origin;
	struct xfrm_selector *partner;
#endif
	u32 genid;
	u32 route_mtu_cached;
	u32 child_mtu_cached;
	u32 route_cookie;
	u32 path_cookie;
};

static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
{
	dst_release(xdst->route);
	if (likely(xdst->u.dst.xfrm))
		xfrm_state_put(xdst->u.dst.xfrm);
#ifdef CONFIG_XFRM_SUB_POLICY
	kfree(xdst->origin);
	xdst->origin = NULL;
	kfree(xdst->partner);
	xdst->partner = NULL;
#endif
}

extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);

struct sec_path
{
	atomic_t		refcnt;
	int			len;
	struct xfrm_state	*xvec[XFRM_MAX_DEPTH];
};

static inline struct sec_path *
secpath_get(struct sec_path *sp)
{
	if (sp)
		atomic_inc(&sp->refcnt);
	return sp;
}

extern void __secpath_destroy(struct sec_path *sp);

static inline void
secpath_put(struct sec_path *sp)
{
	if (sp && atomic_dec_and_test(&sp->refcnt))
		__secpath_destroy(sp);
}

extern struct sec_path *secpath_dup(struct sec_path *src);

static inline void
secpath_reset(struct sk_buff *skb)
{
#ifdef CONFIG_XFRM
	secpath_put(skb->sp);
	skb->sp = NULL;
#endif
}

static inline int
xfrm_addr_any(xfrm_address_t *addr, unsigned short family)
{
	switch (family) {
	case AF_INET:
		return addr->a4 == 0;
	case AF_INET6:
		return ipv6_addr_any((struct in6_addr *)&addr->a6);
	}
	return 0;
}

static inline int
__xfrm4_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
{
	return	(tmpl->saddr.a4 &&
		 tmpl->saddr.a4 != x->props.saddr.a4);
}

static inline int
__xfrm6_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
{
	return	(!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
		 ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
}

static inline int
xfrm_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x, unsigned short family)
{
	switch (family) {
	case AF_INET:
		return __xfrm4_state_addr_cmp(tmpl, x);
	case AF_INET6:
		return __xfrm6_state_addr_cmp(tmpl, x);
	}
	return !0;
}

#ifdef CONFIG_XFRM

extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);

static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
{
	if (sk && sk->sk_policy[XFRM_POLICY_IN])
		return __xfrm_policy_check(sk, dir, skb, family);

	return	(!xfrm_policy_count[dir] && !skb->sp) ||
		(skb->dst->flags & DST_NOPOLICY) ||
		__xfrm_policy_check(sk, dir, skb, family);
}

static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
{
	return xfrm_policy_check(sk, dir, skb, AF_INET);
}

static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
{
	return xfrm_policy_check(sk, dir, skb, AF_INET6);
}

extern int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family);
extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);

static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
{
	return	!xfrm_policy_count[XFRM_POLICY_OUT] ||
		(skb->dst->flags & DST_NOXFRM) ||
		__xfrm_route_forward(skb, family);
}

static inline int xfrm4_route_forward(struct sk_buff *skb)
{
	return xfrm_route_forward(skb, AF_INET);
}

static inline int xfrm6_route_forward(struct sk_buff *skb)
{
	return xfrm_route_forward(skb, AF_INET6);
}

extern int __xfrm_sk_clone_policy(struct sock *sk);

static inline int xfrm_sk_clone_policy(struct sock *sk)
{
	if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
		return __xfrm_sk_clone_policy(sk);
	return 0;
}

extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);