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 37 void syncache_init(void); 38 #ifdef VIMAGE 39 void syncache_destroy(void); 40 #endif 41 void syncache_unreach(struct in_conninfo *, struct tcphdr *); 42 int syncache_expand(struct in_conninfo *, struct tcpopt *, 43 struct tcphdr *, struct socket **, struct mbuf *); 44 void syncache_add(struct in_conninfo *, struct tcpopt *, 45 struct tcphdr *, struct inpcb *, struct socket **, struct mbuf *, 46 void *, void *); 47 void syncache_chkrst(struct in_conninfo *, struct tcphdr *); 48 void syncache_badack(struct in_conninfo *); 49 int syncache_pcbcount(void); 50 int syncache_pcblist(struct sysctl_req *req, int max_pcbs, int *pcbs_exported); 51 52 struct syncache { 53 TAILQ_ENTRY(syncache) sc_hash; 54 struct in_conninfo sc_inc; /* addresses */ 55 int sc_rxttime; /* retransmit time */ 56 u_int16_t sc_rxmits; /* retransmit counter */ 57 u_int32_t sc_tsreflect; /* timestamp to reflect */ 58 u_int32_t sc_ts; /* our timestamp to send */ 59 u_int32_t sc_tsoff; /* ts offset w/ syncookies */ 60 u_int32_t sc_flowlabel; /* IPv6 flowlabel */ 61 tcp_seq sc_irs; /* seq from peer */ 62 tcp_seq sc_iss; /* our ISS */ 63 struct mbuf *sc_ipopts; /* source route */ 64 u_int16_t sc_peer_mss; /* peer's MSS */ 65 u_int16_t sc_wnd; /* advertised window */ 66 u_int8_t sc_ip_ttl; /* IPv4 TTL */ 67 u_int8_t sc_ip_tos; /* IPv4 TOS */ 68 u_int8_t sc_requested_s_scale:4, 69 sc_requested_r_scale:4; 70 u_int16_t sc_flags; 71 #if defined(TCP_OFFLOAD) || !defined(TCP_OFFLOAD_DISABLE) 72 struct toedev *sc_tod; /* entry added by this TOE */ 73 void *sc_todctx; /* TOE driver context */ 74 #endif 75 struct label *sc_label; /* MAC label reference */ 76 struct ucred *sc_cred; /* cred cache for jail checks */ 77 78 void *sc_pspare; /* TCP_SIGNATURE */ 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 struct syncache_head { 95 struct mtx sch_mtx; 96 TAILQ_HEAD(sch_head, syncache) sch_bucket; 97 struct callout sch_timer; 98 int sch_nextc; 99 u_int sch_length; 100 struct tcp_syncache *sch_sc; 101 }; 102 103 #define SYNCOOKIE_SECRET_SIZE 16 104 #define SYNCOOKIE_LIFETIME 15 /* seconds */ 105 106 struct syncookie_secret { 107 volatile u_int oddeven; 108 uint8_t key[2][SYNCOOKIE_SECRET_SIZE]; 109 struct callout reseed; 110 u_int lifetime; 111 }; 112 113 struct tcp_syncache { 114 struct syncache_head *hashbase; 115 uma_zone_t zone; 116 u_int hashsize; 117 u_int hashmask; 118 u_int bucket_limit; 119 u_int cache_limit; 120 u_int rexmt_limit; 121 uint32_t hash_secret; 122 struct vnet *vnet; 123 struct syncookie_secret secret; 124 }; 125 126 /* Internal use for the syncookie functions. */ 127 union syncookie { 128 uint8_t cookie; 129 struct { 130 uint8_t odd_even:1, 131 sack_ok:1, 132 wscale_idx:3, 133 mss_idx:3; 134 } flags; 135 }; 136 137 #endif /* _KERNEL */ 138 #endif /* !_NETINET_TCP_SYNCACHE_H_ */ 139