1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1993, 1994, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)tcp_var.h 8.4 (Berkeley) 5/24/95 32 */ 33 34 #ifndef _NETINET_TCP_SYNCACHE_H_ 35 #define _NETINET_TCP_SYNCACHE_H_ 36 #ifdef _KERNEL 37 38 void syncache_init(void); 39 #ifdef VIMAGE 40 void syncache_destroy(void); 41 #endif 42 void syncache_unreach(struct in_conninfo *, tcp_seq, uint16_t); 43 int syncache_expand(struct in_conninfo *, struct tcpopt *, 44 struct tcphdr *, struct socket **, struct mbuf *, uint16_t); 45 struct socket * syncache_add(struct in_conninfo *, struct tcpopt *, 46 struct tcphdr *, struct inpcb *, struct socket *, struct mbuf *, 47 void *, void *, uint8_t, uint16_t); 48 void syncache_chkrst(struct in_conninfo *, struct tcphdr *, struct mbuf *, 49 uint16_t); 50 void syncache_badack(struct in_conninfo *, uint16_t); 51 int syncache_pcblist(struct sysctl_req *); 52 53 struct 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_int16_t sc_port; /* remote UDP encaps port */ 59 u_int32_t sc_tsreflect; /* timestamp to reflect */ 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; /* TTL / Hop Limit */ 68 u_int8_t sc_ip_tos; /* TOS / Traffic Class */ 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 void *sc_tfo_cookie; /* for TCP Fast Open response */ 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_MASK 0x700 /* ECN codepoint mask */ 94 #define SCF_ECN 0x100 /* send ECN setup packet */ 95 #define SCF_ACE_N 0x400 /* send ACE non-ECT setup */ 96 #define SCF_ACE_0 0x500 /* send ACE ECT0 setup */ 97 #define SCF_ACE_1 0x600 /* send ACE ECT1 setup */ 98 #define SCF_ACE_CE 0x700 /* send ACE CE setup */ 99 100 struct syncache_head { 101 struct mtx sch_mtx; 102 TAILQ_HEAD(sch_head, syncache) sch_bucket; 103 struct callout sch_timer; 104 int sch_nextc; 105 u_int sch_length; 106 struct tcp_syncache *sch_sc; 107 time_t sch_last_overflow; 108 }; 109 110 #define SYNCOOKIE_SECRET_SIZE 16 111 #define SYNCOOKIE_LIFETIME 15 /* seconds */ 112 113 struct syncookie_secret { 114 volatile u_int oddeven; 115 uint8_t key[2][SYNCOOKIE_SECRET_SIZE]; 116 struct callout reseed; 117 u_int lifetime; 118 }; 119 120 #define TCP_SYNCACHE_PAUSE_TIME SYNCOOKIE_LIFETIME 121 #define TCP_SYNCACHE_MAX_BACKOFF 6 /* 16 minutes */ 122 123 struct tcp_syncache { 124 struct syncache_head *hashbase; 125 uma_zone_t zone; 126 u_int hashsize; 127 u_int hashmask; 128 u_int bucket_limit; 129 u_int cache_limit; 130 u_int rexmt_limit; 131 uint32_t hash_secret; 132 struct vnet *vnet; 133 struct syncookie_secret secret; 134 struct mtx pause_mtx; 135 struct callout pause_co; 136 time_t pause_until; 137 uint8_t pause_backoff; 138 volatile bool paused; 139 bool see_other; 140 }; 141 142 /* Internal use for the syncookie functions. */ 143 union syncookie { 144 uint8_t cookie; 145 struct { 146 uint8_t odd_even:1, 147 sack_ok:1, 148 wscale_idx:3, 149 mss_idx:3; 150 } flags; 151 }; 152 153 #endif /* _KERNEL */ 154 #endif /* !_NETINET_TCP_SYNCACHE_H_ */ 155