1/*-
2 * Copyright (c) 1982, 1986, 1993, 1994, 1995
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	@(#)tcp_var.h	8.4 (Berkeley) 5/24/95
30 * $FreeBSD$
31 */
32
33#ifndef _NETINET_TCP_SYNCACHE_H_
34#define _NETINET_TCP_SYNCACHE_H_
35#ifdef _KERNEL
36
37void	 syncache_init(void);
38#ifdef VIMAGE
39void	syncache_destroy(void);
40#endif
41void	 syncache_unreach(struct in_conninfo *, struct tcphdr *);
42int	 syncache_expand(struct in_conninfo *, struct tcpopt *,
43	     struct tcphdr *, struct socket **, struct mbuf *);
44void	 syncache_add(struct in_conninfo *, struct tcpopt *,
45	     struct tcphdr *, struct inpcb *, struct socket **, struct mbuf *);
46void	 tcp_offload_syncache_add(struct in_conninfo *, struct tcpopt *,
47	     struct tcphdr *, struct inpcb *, struct socket **, void *, void *);
48void	 syncache_chkrst(struct in_conninfo *, struct tcphdr *);
49void	 syncache_badack(struct in_conninfo *);
50int	 syncache_pcbcount(void);
51int	 syncache_pcblist(struct sysctl_req *req, int max_pcbs, int *pcbs_exported);
52
53struct syncache {
54	TAILQ_ENTRY(syncache)	sc_hash;
55	struct		in_conninfo sc_inc;	/* addresses */
56	int		sc_rxttime;		/* retransmit time */
57	u_int16_t	sc_rxmits;		/* retransmit counter */
58	u_int32_t	sc_tsreflect;		/* timestamp to reflect */
59	u_int32_t	sc_ts;			/* our timestamp to send */
60	u_int32_t	sc_tsoff;		/* ts offset w/ syncookies */
61	u_int32_t	sc_flowlabel;		/* IPv6 flowlabel */
62	tcp_seq		sc_irs;			/* seq from peer */
63	tcp_seq		sc_iss;			/* our ISS */
64	struct		mbuf *sc_ipopts;	/* source route */
65	u_int16_t	sc_peer_mss;		/* peer's MSS */
66	u_int16_t	sc_wnd;			/* advertised window */
67	u_int8_t	sc_ip_ttl;		/* IPv4 TTL */
68	u_int8_t	sc_ip_tos;		/* IPv4 TOS */
69	u_int8_t	sc_requested_s_scale:4,
70			sc_requested_r_scale:4;
71	u_int16_t	sc_flags;
72#if defined(TCP_OFFLOAD) || !defined(TCP_OFFLOAD_DISABLE)
73	struct toedev	*sc_tod;		/* entry added by this TOE */
74	void		*sc_todctx;		/* TOE driver context */
75#endif
76	struct label	*sc_label;		/* MAC label reference */
77	struct ucred	*sc_cred;		/* cred cache for jail checks */
78
79	u_int32_t	sc_spare[2];		/* UTO */
80};
81
82/*
83 * Flags for the sc_flags field.
84 */
85#define SCF_NOOPT	0x01			/* no TCP options */
86#define SCF_WINSCALE	0x02			/* negotiated window scaling */
87#define SCF_TIMESTAMP	0x04			/* negotiated timestamps */
88						/* MSS is implicit */
89#define SCF_UNREACH	0x10			/* icmp unreachable received */
90#define SCF_SIGNATURE	0x20			/* send MD5 digests */
91#define SCF_SACK	0x80			/* send SACK option */
92#define SCF_ECN		0x100			/* send ECN setup packet */
93
94#define	SYNCOOKIE_SECRET_SIZE	8	/* dwords */
95#define	SYNCOOKIE_LIFETIME	16	/* seconds */
96
97struct syncache_head {
98	struct vnet	*sch_vnet;
99	struct mtx	sch_mtx;
100	TAILQ_HEAD(sch_head, syncache)	sch_bucket;
101	struct callout	sch_timer;
102	int		sch_nextc;
103	u_int		sch_length;
104	u_int		sch_oddeven;
105	u_int32_t	sch_secbits_odd[SYNCOOKIE_SECRET_SIZE];
106	u_int32_t	sch_secbits_even[SYNCOOKIE_SECRET_SIZE];
107	u_int		sch_reseed;		/* time_uptime, seconds */
108};
109
110struct tcp_syncache {
111	struct	syncache_head *hashbase;
112	uma_zone_t zone;
113	u_int	hashsize;
114	u_int	hashmask;
115	u_int	bucket_limit;
116	u_int	cache_limit;
117	u_int	rexmt_limit;
118	u_int	hash_secret;
119};
120
121#endif /* _KERNEL */
122#endif /* !_NETINET_TCP_SYNCACHE_H_ */
123