/*- * SPDX-License-Identifier: BSD-3-Clause * * 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. * 3. 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. */ #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 *, tcp_seq, uint16_t); int syncache_expand(struct in_conninfo *, struct tcpopt *, struct tcphdr *, struct socket **, struct mbuf *, uint16_t); struct socket * syncache_add(struct in_conninfo *, struct tcpopt *, struct tcphdr *, struct inpcb *, struct socket *, struct mbuf *, void *, void *, uint8_t, uint16_t); void syncache_chkrst(struct in_conninfo *, struct tcphdr *, uint16_t); int syncache_pcblist(struct sysctl_req *); 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_int16_t sc_port; /* remote UDP encaps port */ u_int32_t sc_tsreflect; /* timestamp to reflect */ 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; /* TTL / Hop Limit */ u_int8_t sc_ip_tos; /* TOS / Traffic Class */ u_int8_t sc_requested_s_scale:4, sc_requested_r_scale:4; uint8_t sc_numa_domain; u_int16_t sc_flags; u_int32_t sc_challenge_ack_cnt; /* chall. ACKs sent in epoch */ sbintime_t sc_challenge_ack_end; /* End of chall. ack epoch */ #if defined(TCP_OFFLOAD) 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_tfo_cookie; /* for TCP Fast Open response */ uint32_t sc_flowtype; /* flowid from SYN packet .. */ uint32_t sc_flowid; /* .. or calculated by RSS */ }; /* * 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_MASK 0x700 /* ECN codepoint mask */ #define SCF_ECN 0x100 /* send ECN setup packet */ #define SCF_ACE_N 0x400 /* send ACE non-ECT setup */ #define SCF_ACE_0 0x500 /* send ACE ECT0 setup */ #define SCF_ACE_1 0x600 /* send ACE ECT1 setup */ #define SCF_ACE_CE 0x700 /* send ACE CE setup */ 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; time_t sch_last_overflow; }; #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; }; #define TCP_SYNCACHE_PAUSE_TIME SYNCOOKIE_LIFETIME #define TCP_SYNCACHE_MAX_BACKOFF 6 /* 16 minutes */ 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; uint32_t hash_secret; #ifdef VIMAGE struct vnet *vnet; #endif struct syncookie_secret secret; struct mtx pause_mtx; struct callout pause_co; time_t pause_until; uint8_t pause_backoff; volatile bool paused; bool see_other; }; /* 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_ */
