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 * 3. 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 *, tcp_seq); 42 int syncache_expand(struct in_conninfo *, struct tcpopt *, 43 struct tcphdr *, struct socket **, struct mbuf *); 44 int 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_pcblist(struct sysctl_req *req, int max_pcbs, int *pcbs_exported); 50 51 struct syncache { 52 TAILQ_ENTRY(syncache) sc_hash; 53 struct in_conninfo sc_inc; /* addresses */ 54 int sc_rxttime; /* retransmit time */ 55 u_int16_t sc_rxmits; /* retransmit counter */ 56 u_int32_t sc_tsreflect; /* timestamp to reflect */ 57 u_int32_t sc_ts; /* our timestamp to send */ 58 u_int32_t sc_tsoff; /* ts offset w/ syncookies */ 59 u_int32_t sc_flowlabel; /* IPv6 flowlabel */ 60 tcp_seq sc_irs; /* seq from peer */ 61 tcp_seq sc_iss; /* our ISS */ 62 struct mbuf *sc_ipopts; /* source route */ 63 u_int16_t sc_peer_mss; /* peer's MSS */ 64 u_int16_t sc_wnd; /* advertised window */ 65 u_int8_t sc_ip_ttl; /* IPv4 TTL */ 66 u_int8_t sc_ip_tos; /* IPv4 TOS */ 67 u_int8_t sc_requested_s_scale:4, 68 sc_requested_r_scale:4; 69 u_int16_t sc_flags; 70 #if defined(TCP_OFFLOAD) || !defined(TCP_OFFLOAD_DISABLE) 71 struct toedev *sc_tod; /* entry added by this TOE */ 72 void *sc_todctx; /* TOE driver context */ 73 #endif 74 struct label *sc_label; /* MAC label reference */ 75 struct ucred *sc_cred; /* cred cache for jail checks */ 76 #ifdef TCP_RFC7413 77 void *sc_tfo_cookie; /* for TCP Fast Open response */ 78 #endif 79 void *sc_pspare; /* TCP_SIGNATURE */ 80 u_int32_t sc_spare[2]; /* UTO */ 81 }; 82 83 /* 84 * Flags for the sc_flags field. 85 */ 86 #define SCF_NOOPT 0x01 /* no TCP options */ 87 #define SCF_WINSCALE 0x02 /* negotiated window scaling */ 88 #define SCF_TIMESTAMP 0x04 /* negotiated timestamps */ 89 /* MSS is implicit */ 90 #define SCF_UNREACH 0x10 /* icmp unreachable received */ 91 #define SCF_SIGNATURE 0x20 /* send MD5 digests */ 92 #define SCF_SACK 0x80 /* send SACK option */ 93 #define SCF_ECN 0x100 /* send ECN setup packet */ 94 95 struct syncache_head { 96 struct mtx sch_mtx; 97 TAILQ_HEAD(sch_head, syncache) sch_bucket; 98 struct callout sch_timer; 99 int sch_nextc; 100 u_int sch_length; 101 struct tcp_syncache *sch_sc; 102 time_t sch_last_overflow; 103 }; 104 105 #define SYNCOOKIE_SECRET_SIZE 16 106 #define SYNCOOKIE_LIFETIME 15 /* seconds */ 107 108 struct syncookie_secret { 109 volatile u_int oddeven; 110 uint8_t key[2][SYNCOOKIE_SECRET_SIZE]; 111 struct callout reseed; 112 u_int lifetime; 113 }; 114 115 struct tcp_syncache { 116 struct syncache_head *hashbase; 117 uma_zone_t zone; 118 u_int hashsize; 119 u_int hashmask; 120 u_int bucket_limit; 121 u_int cache_limit; 122 u_int rexmt_limit; 123 uint32_t hash_secret; 124 struct vnet *vnet; 125 struct syncookie_secret secret; 126 }; 127 128 /* Internal use for the syncookie functions. */ 129 union syncookie { 130 uint8_t cookie; 131 struct { 132 uint8_t odd_even:1, 133 sack_ok:1, 134 wscale_idx:3, 135 mss_idx:3; 136 } flags; 137 }; 138 139 #endif /* _KERNEL */ 140 #endif /* !_NETINET_TCP_SYNCACHE_H_ */ 141