aboutsummaryrefslogtreecommitdiff
path: root/sys/netinet/tcp_syncache.h
blob: fb9a6c64c452a79b1ce7d79c91df3f28b8f47fa4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
/*-
 * Copyright (c) 1982, 1986, 1993, 1994, 1995
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)tcp_var.h	8.4 (Berkeley) 5/24/95
 * $FreeBSD$
 */

#ifndef _NETINET_TCP_SYNCACHE_H_
#define _NETINET_TCP_SYNCACHE_H_
#ifdef _KERNEL

void	 syncache_init(void);
#ifdef VIMAGE
void	syncache_destroy(void);
#endif
void	 syncache_unreach(struct in_conninfo *, struct tcphdr *);
int	 syncache_expand(struct in_conninfo *, struct tcpopt *,
	     struct tcphdr *, struct socket **, struct mbuf *);
void	 syncache_add(struct in_conninfo *, struct tcpopt *,
	     struct tcphdr *, struct inpcb *, struct socket **, struct mbuf *,
	     void *, void *);
void	 syncache_chkrst(struct in_conninfo *, struct tcphdr *);
void	 syncache_badack(struct in_conninfo *);
int	 syncache_pcbcount(void);
int	 syncache_pcblist(struct sysctl_req *req, int max_pcbs, int *pcbs_exported);

struct syncache {
	TAILQ_ENTRY(syncache)	sc_hash;
	struct		in_conninfo sc_inc;	/* addresses */
	int		sc_rxttime;		/* retransmit time */
	u_int16_t	sc_rxmits;		/* retransmit counter */
	u_int32_t	sc_tsreflect;		/* timestamp to reflect */
	u_int32_t	sc_ts;			/* our timestamp to send */
	u_int32_t	sc_tsoff;		/* ts offset w/ syncookies */
	u_int32_t	sc_flowlabel;		/* IPv6 flowlabel */
	tcp_seq		sc_irs;			/* seq from peer */
	tcp_seq		sc_iss;			/* our ISS */
	struct		mbuf *sc_ipopts;	/* source route */
	u_int16_t	sc_peer_mss;		/* peer's MSS */
	u_int16_t	sc_wnd;			/* advertised window */
	u_int8_t	sc_ip_ttl;		/* IPv4 TTL */
	u_int8_t	sc_ip_tos;		/* IPv4 TOS */
	u_int8_t	sc_requested_s_scale:4,
			sc_requested_r_scale:4;
	u_int16_t	sc_flags;
#if defined(TCP_OFFLOAD) || !defined(TCP_OFFLOAD_DISABLE)
	struct toedev	*sc_tod;		/* entry added by this TOE */
	void		*sc_todctx;		/* TOE driver context */
#endif
	struct label	*sc_label;		/* MAC label reference */
	struct ucred	*sc_cred;		/* cred cache for jail checks */

	void		*sc_pspare;		/* TCP_SIGNATURE */
	u_int32_t	sc_spare[2];		/* UTO */
};

/*
 * Flags for the sc_flags field.
 */
#define SCF_NOOPT	0x01			/* no TCP options */
#define SCF_WINSCALE	0x02			/* negotiated window scaling */
#define SCF_TIMESTAMP	0x04			/* negotiated timestamps */
						/* MSS is implicit */
#define SCF_UNREACH	0x10			/* icmp unreachable received */
#define SCF_SIGNATURE	0x20			/* send MD5 digests */
#define SCF_SACK	0x80			/* send SACK option */
#define SCF_ECN		0x100			/* send ECN setup packet */

struct syncache_head {
	struct mtx	sch_mtx;
	TAILQ_HEAD(sch_head, syncache)	sch_bucket;
	struct callout	sch_timer;
	int		sch_nextc;
	u_int		sch_length;
	struct tcp_syncache *sch_sc;
};

#define	SYNCOOKIE_SECRET_SIZE	16
#define	SYNCOOKIE_LIFETIME	15		/* seconds */

struct syncookie_secret {
	volatile u_int oddeven;
	uint8_t key[2][SYNCOOKIE_SECRET_SIZE];
	struct callout reseed;
	u_int lifetime;
};

struct tcp_syncache {
	struct	syncache_head *hashbase;
	uma_zone_t zone;
	u_int	hashsize;
	u_int	hashmask;
	u_int	bucket_limit;
	u_int	cache_limit;
	u_int	rexmt_limit;
	u_int	hash_secret;
	struct vnet *vnet;
	struct syncookie_secret secret;
};

/* Internal use for the syncookie functions. */
union syncookie {
	uint8_t cookie;
	struct {
		uint8_t odd_even:1,
			sack_ok:1,
			wscale_idx:3,
			mss_idx:3;
	} flags;
};

#endif /* _KERNEL */
#endif /* !_NETINET_TCP_SYNCACHE_H_ */