gems-kernel/source/THIRDPARTY/xnu/bsd/netinet/tcp_var.h
2024-06-03 11:29:39 -05:00

1838 lines
92 KiB
C

/*
* Copyright (c) 2000-2022 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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: src/sys/netinet/tcp_var.h,v 1.56.2.8 2001/08/22 00:59:13 silby Exp $
*/
#ifndef _NETINET_TCP_VAR_H_
#define _NETINET_TCP_VAR_H_
#include <sys/types.h>
#include <sys/appleapiopts.h>
#include <sys/queue.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp.h>
#include <netinet/tcp_timer.h>
#if !KERNEL
#include <TargetConditionals.h>
#endif
#if defined(__LP64__)
#define _TCPCB_PTR(x) u_int32_t
#define _TCPCB_LIST_HEAD(name, type) \
struct name { \
u_int32_t lh_first; \
}
#else
#define _TCPCB_PTR(x) x
#define _TCPCB_LIST_HEAD(name, type) LIST_HEAD(name, type)
#endif
#ifdef KERNEL_PRIVATE
#define TCP_RETRANSHZ 1000 /* granularity of TCP timestamps, 1ms */
/* Minimum time quantum within which the timers are coalesced */
#define TCP_TIMER_10MS_QUANTUM (TCP_RETRANSHZ/100) /* every 10ms */
#define TCP_TIMER_100MS_QUANTUM (TCP_RETRANSHZ/10) /* every 100ms */
#define TCP_TIMER_500MS_QUANTUM (TCP_RETRANSHZ/2) /* every 500ms */
#define TCP_RETRANSHZ_TO_USEC 1000
#define N_TIME_WAIT_SLOTS 128 /* must be power of 2 */
/* Always allow at least 16 packets worth of recv window when adjusting
* recv window using inter-packet arrival jitter.
*/
#define MIN_IAJ_WIN 16
/* A variation in delay of this many milliseconds is tolerable. This limit has to
* be low but greater than zero. We also use standard deviation on jitter to adjust
* this limit for different link and connection types.
*/
#define ALLOWED_IAJ 5
/* Ignore the first few packets on a connection until the ACK clock gets going
*/
#define IAJ_IGNORE_PKTCNT 40
/* Let the accumulated IAJ value increase by this threshold at most. This limit
* will control how many ALLOWED_IAJ measurements a receiver will have to see
* before opening the receive window
*/
#define ACC_IAJ_HIGH_THRESH 100
/* When accumulated IAJ reaches this value, the receiver starts to react by
* closing the window
*/
#define ACC_IAJ_REACT_LIMIT 200
/* If the number of small packets (smaller than IAJ packet size) seen on a
* connection is more than this threshold, reset the size and learn it again.
* This is needed because the sender might send smaller segments after PMTU
* discovery and the receiver has to learn the new size.
*/
#define RESET_IAJ_SIZE_THRESH 20
/*
* Adaptive timeout is a read/write timeout specified by the application to
* get a socket event when the transport layer detects a stall in data
* transfer. The value specified is the number of probes that can be sent
* to the peer before generating an event. Since it is not specified as
* a time value, the timeout will adjust based on the RTT seen on the link.
* The timeout will start only when there is an indication that the read/write
* operation is not making progress.
*
* If a write operation stalls, the probe will be retransmission of data.
* If a read operation stalls, the probe will be a keep-alive packet.
*
* The maximum value of adaptive timeout is set to 10 which will allow
* transmission of enough number of probes to the peer.
*/
#define TCP_ADAPTIVE_TIMEOUT_MAX 10
#define TCP_CONNECTIVITY_PROBES_MAX 5
/* 3 bit mask used for Accurate ECN ACE field */
#define TCP_ACE_MASK (0x7)
/* Divisor used for Accurate ECN ACE field */
#define TCP_ACE_DIV (1 << 3)
/* 24 bit mask used for Accurate ECN option */
#define TCP_ACO_MASK (0xFFFFFF)
/*
* Kernel variables for tcp.
*/
/* TCP segment queue entry */
struct tseg_qent {
LIST_ENTRY(tseg_qent) tqe_q;
int tqe_len; /* TCP segment data length */
struct tcphdr *tqe_th; /* a pointer to tcp header */
struct mbuf *tqe_m; /* mbuf contains packet */
};
LIST_HEAD(tsegqe_head, tseg_qent);
struct sackblk {
tcp_seq start; /* start seq no. of sack block */
tcp_seq end; /* end seq no. */
};
struct sackhole {
tcp_seq start; /* start seq no. of hole */
tcp_seq end; /* end seq no. */
tcp_seq rxmit; /* next seq. no in hole to be retransmitted */
u_int32_t rxmit_start; /* timestamp of first retransmission */
TAILQ_ENTRY(sackhole) scblink; /* scoreboard linkage */
};
struct sackhint {
struct sackhole *nexthole;
int sack_bytes_rexmit;
int sack_bytes_acked;
};
struct tcp_rxt_seg {
tcp_seq rx_start;
tcp_seq rx_end;
u_int16_t rx_count;
u_int16_t rx_flags;
#define TCP_RXT_SPURIOUS 0x1 /* received DSACK notification */
SLIST_ENTRY(tcp_rxt_seg) rx_link;
};
struct tcp_notify_ack_marker {
tcp_seq notify_snd_una; /* Notify when snd_una crosses this seq */
tcp_notify_ack_id_t notify_id;
SLIST_ENTRY(tcp_notify_ack_marker) notify_next;
};
struct tcptemp {
u_char tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */
struct tcphdr tt_t;
};
struct bwmeas {
tcp_seq bw_start; /* start of bw measurement */
uint32_t bw_ts; /* timestamp when bw measurement started */
uint32_t bw_size; /* burst size in bytes for this bw measurement */
uint32_t bw_minsizepkts; /* Min burst size as segments */
uint32_t bw_maxsizepkts; /* Max burst size as segments */
uint32_t bw_minsize; /* Min size in bytes */
uint32_t bw_maxsize; /* Max size in bytes */
uint32_t bw_sndbw; /* Measured send bandwidth */
uint32_t bw_sndbw_max; /* Max measured bandwidth */
uint32_t bw_rcvbw_max; /* Max receive bandwidth measured */
};
/* MPTCP Data sequence map entry */
struct mpt_dsn_map {
uint64_t mpt_dsn; /* data seq num recvd */
uint32_t mpt_sseq; /* relative subflow # */
uint16_t mpt_len; /* length of mapping */
uint16_t mpt_csum; /* checksum value if on */
uint8_t mpt_dfin; /* It's a DATA_FIN */
};
#define tcp6cb tcpcb /* for KAME src sync over BSD*'s */
struct tcp_ccstate {
union {
struct tcp_cubic_state {
u_int32_t tc_last_max; /* cwnd at last loss */
u_int32_t tc_epoch_start; /* TS of last loss */
u_int32_t tc_origin_point; /* window at the start of an epoch */
u_int32_t tc_tcp_win; /* computed tcp win */
u_int32_t tc_tcp_bytes_acked; /* bytes acked */
u_int32_t tc_avg_lastmax; /* Average of last max */
u_int32_t tc_mean_deviation; /* Mean absolute deviation */
float tc_epoch_period; /* K parameter */
} _cubic_state_;
#define cub_last_max __u__._cubic_state_.tc_last_max
#define cub_epoch_start __u__._cubic_state_.tc_epoch_start
#define cub_origin_point __u__._cubic_state_.tc_origin_point
#define cub_tcp_win __u__._cubic_state_.tc_tcp_win
#define cub_tcp_bytes_acked __u__._cubic_state_.tc_tcp_bytes_acked
#define cub_epoch_period __u__._cubic_state_.tc_epoch_period
#define cub_avg_lastmax __u__._cubic_state_.tc_avg_lastmax
#define cub_mean_dev __u__._cubic_state_.tc_mean_deviation
struct tcp_ledbat_state {
uint32_t num_slowdown_events;
uint32_t slowdown_ts;
uint32_t slowdown_begin;
uint32_t md_bytes_acked;
} _ledbat_state_;
#define ledbat_slowdown_events __u__._ledbat_state_.num_slowdown_events
#define ledbat_slowdown_ts __u__._ledbat_state_.slowdown_ts
#define ledbat_slowdown_begin __u__._ledbat_state_.slowdown_begin
#define ledbat_md_bytes_acked __u__._ledbat_state_.md_bytes_acked
} __u__;
};
struct tcp_rledbat_state {
uint32_t num_slowdown_events; /* Number of slowdown events until reset */
uint32_t slowdown_ts; /* Next slowdown timestamp */
uint32_t slowdown_begin; /* Slowdown begin time */
uint32_t reduction_end; /* Used to track rl_win reduction once per RTT */
uint32_t rcvd_bytes; /* bytes received used for byte counting */
uint32_t md_rcvd_bytes; /* bytes received during MD used for byte counting */
uint32_t win; /* receive Ledbat window size */
uint32_t ssthresh; /* receive Ledbat ssthresh */
uint32_t drained_bytes; /* bytes drained from the flight-size */
uint32_t win_ws; /* receive Ledbat window after avoiding window shrinking */
};
/*
* Tcp control block, one per tcp; fields:
* Organized for 16 byte cacheline efficiency.
*/
struct tcpcb {
struct tsegqe_head t_segq;
uint32_t t_dupacks; /* consecutive dup acks recd */
int t_state; /* state of this connection */
uint32_t t_timer[TCPT_NTIMERS]; /* tcp timers */
struct tcptimerentry tentry; /* entry in timer list */
struct inpcb *t_inpcb; /* back pointer to internet pcb */
uint32_t t_flags;
#define TF_ACKNOW 0x00001 /* ack peer immediately */
#define TF_DELACK 0x00002 /* ack, but try to delay it */
#define TF_NODELAY 0x00004 /* don't delay packets to coalesce */
#define TF_NOOPT 0x00008 /* don't use tcp options */
#define TF_SENTFIN 0x00010 /* have sent FIN */
#define TF_REQ_SCALE 0x00020 /* have/will request window scaling */
#define TF_RCVD_SCALE 0x00040 /* other side has requested scaling */
#define TF_REQ_TSTMP 0x00080 /* have/will request timestamps */
#define TF_RCVD_TSTMP 0x00100 /* a timestamp was received in SYN */
#define TF_SACK_PERMIT 0x00200 /* other side said I could SACK */
#define TF_NEEDSYN 0x00400 /* send SYN (implicit state) - unused but needed for backwards compatibility */
#define TF_NEEDFIN 0x00800 /* send FIN (implicit state) */
#define TF_NOPUSH 0x01000 /* don't push */
#define TF_REQ_CC 0x02000 /* have/will request CC */
#define TF_RCVD_CC 0x04000 /* a CC was received in SYN */
#define TF_SENDCCNEW 0x08000 /* Unused */
#define TF_MORETOCOME 0x10000 /* More data to be appended to sock */
#define TF_LOCAL 0x20000 /* connection to a host on local link */
#define TF_RXWIN0SENT 0x40000 /* sent a receiver win 0 in response */
#define TF_SLOWLINK 0x80000 /* route is a on a modem speed link */
#define TF_LASTIDLE 0x100000 /* connection was previously idle */
#define TF_FASTRECOVERY 0x200000 /* in NewReno Fast Recovery */
#define TF_WASFRECOVERY 0x400000 /* was in NewReno Fast Recovery */
#define TF_SIGNATURE 0x800000 /* require MD5 digests (RFC2385) */
#define TF_MAXSEGSNT 0x1000000 /* last segment sent was a full segment */
#define TF_STREAMING_ON 0x2000000 /* Receiver detected streaming */
#define TF_PMTUD 0x4000000 /* Perform Path MTU Discovery for this connection */
#define TF_CLOSING 0x8000000 /* pending tcp close */
#define TF_TSO 0x10000000 /* TCP Segment Offloading is enable on this connection */
#define TF_BLACKHOLE 0x20000000 /* Path MTU Discovery Black Hole detection */
#define TF_TIMER_ONLIST 0x40000000 /* pcb is on tcp_timer_list */
#define TF_STRETCHACK 0x80000000 /* receiver is going to delay acks */
tcp_seq snd_una; /* send unacknowledged */
tcp_seq snd_max; /* highest sequence number sent;
* used to recognize retransmits
*/
tcp_seq snd_nxt; /* send next */
tcp_seq snd_up; /* send urgent pointer */
tcp_seq snd_wl1; /* window update seg seq number */
tcp_seq snd_wl2; /* window update seg ack number */
tcp_seq iss; /* initial send sequence number */
tcp_seq irs; /* initial receive sequence number */
tcp_seq rcv_nxt; /* receive next */
tcp_seq rcv_adv; /* advertised window */
uint32_t rcv_wnd; /* receive window */
uint32_t t_last_recwin;
tcp_seq rcv_up; /* receive urgent pointer */
uint32_t snd_wnd; /* send window */
uint32_t snd_cwnd; /* congestion-controlled window */
uint32_t snd_ssthresh; /* snd_cwnd size threshold for
* for slow start exponential to
* linear switch
*/
tcp_seq snd_recover; /* for use in NewReno Fast Recovery */
uint32_t t_maxopd; /* mss plus options */
uint32_t t_rcvtime; /* time at which a packet was received */
uint32_t t_sndtime; /* time at which we last sent new data */
uint32_t t_starttime; /* time connection was established */
int t_rtttime; /* tcp clock when rtt calculation was started */
tcp_seq t_rtseq; /* sequence number being timed */
uint32_t rfbuf_ts; /* recv buffer autoscaling timestamp */
uint32_t rfbuf_cnt; /* recv buffer autoscaling byte count */
uint32_t rfbuf_space; /* Current "ideal" estimate of the space */
int t_rxtcur; /* current retransmit value (ticks) */
unsigned int t_maxseg; /* maximum segment size */
int t_srtt; /* smoothed round-trip time */
int t_rttvar; /* variance in round-trip time */
uint64_t t_accsleep_ms; /* accumulated sleep time since last boot */
uint32_t t_reassqlen; /* length of reassembly queue */
uint32_t t_reassq_mbcnt; /* amount in bytes of mbuf space used */
uint16_t t_rxtshift; /* log(2) of rexmt exp. backoff */
uint32_t t_rttmin; /* minimum rtt allowed */
uint32_t t_rttbest; /* best rtt we've seen */
uint32_t t_rttcur; /* most recent value of rtt */
uint32_t t_rttupdated; /* number of times rtt sampled */
uint32_t t_rxt_conndroptime; /* retxmt conn gets dropped after this time, when set */
uint32_t t_rxtstart; /* time at which retransmission started */
uint32_t max_sndwnd; /* largest window peer has offered */
int t_softerror; /* possible error not yet reported */
/* out-of-band data */
char t_oobflags; /* have some */
char t_iobc; /* input character */
#define TCPOOB_HAVEDATA 0x01
#define TCPOOB_HADDATA 0x02
/* RFC 1323 variables */
u_int8_t snd_scale; /* window scaling for send window */
u_int8_t rcv_scale; /* window scaling for recv window */
u_int8_t request_r_scale; /* pending window scaling */
u_int8_t requested_s_scale;
u_int8_t tcp_cc_index; /* index of congestion control algorithm */
u_int8_t t_adaptive_rtimo; /* Read timeout used as a multiple of RTT */
u_int8_t t_adaptive_wtimo; /* Write timeout used as a multiple of RTT */
u_int8_t t_stretchack_delayed; /* stretch ack delayed */
/* State for limiting early retransmits when SACK is not enabled */
u_int16_t t_early_rexmt_count; /* count of early rexmts */
u_int32_t t_early_rexmt_win; /* window for limiting early rexmts */
u_int32_t ts_recent; /* timestamp echo data */
u_int32_t ts_recent_age; /* when last updated */
tcp_seq last_ack_sent;
/* RFC 3465 variables */
u_int32_t t_bytes_acked; /* ABC "bytes_acked" parameter */
int t_lastchain; /* amount of packets chained last time around */
uint16_t t_unacksegs; /* received but unacked segments for delaying acks */
uint16_t t_unacksegs_ce; /* received but unacked segments/pure ACKs that were CE marked */
/*
* Pretty arbitrary value ;-)
* Goal is to make sure that some ACKs are being sent more frequently
* to allow the other side to ramp-up.
*/
#define TCP_FORCED_ACKS_COUNT 16
uint16_t t_forced_acks; /* count of pure ACKs that need to be forced out */
uint8_t t_rexmtthresh; /* duplicate ack threshold for entering fast recovery */
uint8_t t_rtimo_probes; /* number of adaptive rtimo probes sent */
uint32_t t_persist_timeout; /* ZWP persistence limit as set by PERSIST_TIMEOUT */
uint32_t t_persist_stop; /* persistence limit deadline if triggered by ZWP */
uint32_t t_notsent_lowat; /* Low water for not sent data */
/* Receiver state for stretch-ack algorithm */
u_int32_t rcv_unackwin; /* to measure win for stretching acks */
u_int32_t rcv_by_unackwin; /* bytes seen during the last ack-stretching win */
u_int32_t rcv_by_unackhalfwin;
u_int32_t rcv_nostrack_ts; /* timestamp when stretch ack was disabled automatically */
u_int32_t rcv_nostrack_pkts; /* pkts received since strech ack was disabled */
u_int16_t rcv_waitforss; /* wait for packets during slow-start */
/* ECN stats */
u_int32_t ecn_flags;
#define TE_SETUPSENT 0x00000001 /* We have sent classic ECN-SETUP SYN or SYN-ACK */
#define TE_SETUPRECEIVED 0x00000002 /* We have received classic ECN-SETUP SYN or SYN-ACK */
#define TE_SENDIPECT 0x00000004 /* We haven't sent or received non-ECN-setup SYN or SYN-ACK, set IP ECT on outbound packet */
#define TE_SENDCWR 0x00000008 /* Next non-retransmit should have TCP CWR set, only used for classic ECN */
#define TE_SENDECE 0x00000010 /* Next packet should have TCP ECE set, only used for classic ECN */
#define TE_INRECOVERY 0x00000020 /* connection entered recovery after receiving ECE */
#define TE_RECV_ECN_CE 0x00000040 /* Received IPTOS_ECN_CE marking atleast once */
#define TE_RECV_ECN_ECE 0x00000080 /* Received ECE marking atleast once */
#define TE_LOST_SYN 0x00000100 /* Lost SYN with ECN setup */
#define TE_LOST_SYNACK 0x00000200 /* Lost SYN-ACK with ECN setup */
#define TE_ECN_MODE_ENABLE 0x00000400 /* Option ECN mode set to enable */
#define TE_ECN_MODE_DISABLE 0x00000800 /* Option ECN mode set to disable */
#define TE_ENABLE_ECN 0x00001000 /* Enable negotiation of ECN */
#define TE_ECN_ON (TE_SETUPSENT | TE_SETUPRECEIVED) /* ECN was successfully negotiated on a connection */
#define TE_CEHEURI_SET 0x00002000 /* We did our CE-probing at the beginning */
#define TE_CLIENT_SETUP 0x00004000 /* setup from client side */
#define TE_RCVD_SYN_RST 0x00008000 /* Received RST to the first ECN enabled SYN */
#define TE_ACE_SETUP_NON_ECT 0x00010000 /* Encode received non-ECT either for SYN-ACK (server) or final ACK (client) */
#define TE_ACE_SETUP_ECT1 0x00020000 /* Encode received ECT1 either for SYN-ACK (server) or final ACK (client) */
#define TE_ACE_SETUP_ECT0 0x00040000 /* Encode received ECT0 either for SYN-ACK (server) or final ACK (client) */
#define TE_ACE_SETUP_CE 0x00080000 /* Encode received CE either for SYN-ACK (server) or final ACK (client) */
#define TE_ACE_SETUPSENT 0x00100000 /* We have sent Accurate ECN setup SYN or SYN-ACK */
#define TE_ACE_SETUPRECEIVED 0x00200000 /* We have received Accurate ECN setup SYN or SYN-ACK */
#define TE_ACC_ECN_ON (TE_ACE_SETUPSENT | TE_ACE_SETUPRECEIVED) /* Accurate ECN was negotiated */
#define TE_ACE_FINAL_ACK_3WHS 0x00400000 /* Client has received SYN-ACK and will now send final ACK of 3WHS, only used for AccECN */
#define TE_ACO_ECT1 0x00800000 /* ECT1 counter changed flag, used to decide ordering for AccECN option */
#define TE_ACO_ECT0 0x01000000 /* ECT0 counter changed flag, used to decide ordering for AccECN option */
#define TE_RETRY_WITHOUT_ACO 0x02000000 /* Data segment with AccECN option was not acknowledged, retry without AccECN option */
#define TE_FORCE_ECT1 0x40000000 /* Force setting ECT1 on outgoing packets for testing purpose */
#define TE_FORCE_ECT0 0x80000000 /* Force setting ECT0 on outgoing packets for testing purpose */
u_int32_t t_ecn_recv_ce; /* Received CE from the network */
u_int32_t t_ecn_recv_cwr; /* Packets received with CWR */
uint32_t t_client_accecn_state; /* Client's Accurate ECN state */
uint32_t t_server_accecn_state; /* Server's Accurate ECN state */
uint64_t t_ecn_capable_packets_sent; /* Packets sent with ECT */
uint64_t t_ecn_capable_packets_acked; /* Packets sent with ECT that were acked */
uint64_t t_ecn_capable_packets_marked; /* Packets sent with ECT that were marked */
uint64_t t_ecn_capable_packets_lost; /* Packets sent with ECT that were lost */
uint16_t t_prev_ace_flags; /* ACE flags that were sent in previous packet, used for retransmitting after timeout */
uint8_t t_prev_ip_ecn; /* IP ECN flag on the previous packet, used for change-triggered ACKs */
/* ACE CE packet counters */
uint32_t t_rcv_ce_packets; /* Number of CE received packets at the receiver */
uint32_t t_snd_ce_packets; /* Synced number of CE received feedback at the sender */
uint32_t t_delta_ce_packets; /* Change in CE count between previous and current ACK */
/* AccECN option byte counters, sender side counters (s_) must not be used until they are synced from TCP options */
uint64_t t_rcv_ect1_bytes; /* ECT1 byte counter at the receiver, used for AccECN option feedback */
uint64_t t_rcv_ect0_bytes; /* ECT0 byte counter at the receiver, used for AccECN option feedback */
uint64_t t_rcv_ce_bytes; /* CE byte counter at the receiver, used for AccECN option feedback */
uint64_t t_snd_ect1_bytes; /* Synced ECT1 byte counter at the sender */
uint64_t t_snd_ect0_bytes; /* Synced ECT0 byte counter at the sender */
uint64_t t_snd_ce_bytes; /* Synced CE byte counter at the sender */
/* state for bad retransmit recovery */
u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
tcp_seq snd_recover_prev; /* snd_recover prior to retransmit */
int t_srtt_prev; /* srtt prior to retransmit */
int t_rttvar_prev; /* rttvar prior to retransmit */
u_int32_t t_badrexmt_time; /* bad rexmt detection time */
/* Packet reordering metric */
u_int32_t t_reorderwin; /* Reordering late time offset */
/* SACK related state */
int16_t snd_numholes; /* number of holes seen by sender */
tcp_seq sack_newdata; /* New data xmitted in this recovery
* episode starts at this seq number */
TAILQ_HEAD(sackhole_head, sackhole) snd_holes;
/* SACK scoreboard (sorted) */
tcp_seq snd_fack; /* last seq number(+1) sack'd by rcv'r*/
int rcv_numsacks; /* # distinct sack blks present */
struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */
struct sackhint sackhint; /* SACK scoreboard hint */
tcp_seq send_highest_sack; /* Sequence number of fresh data sent after the most recent fast-retransmit */
int t_new_dupacks; /* Dupacks received above send_highest_sack */
struct mbuf *t_pktlist_head; /* First packet in transmit chain */
struct mbuf *t_pktlist_tail; /* Last packet in transmit chain */
u_int32_t t_pktlist_sentlen; /* total bytes in transmit chain */
u_int32_t t_keepidle; /* keepalive idle timer (override global if > 0) */
u_int32_t t_keepinit; /* connection timeout, i.e. idle time
* in SYN_SENT or SYN_RECV state */
u_int32_t t_keepintvl; /* interval between keepalives */
u_int32_t t_keepcnt; /* number of keepalives before close */
u_int32_t tso_max_segment_size; /* TSO maximum segment unit for NIC */
u_int16_t t_pmtud_lastseg_size; /* size of the last sent segment */
u_int32_t t_pmtud_saved_maxopd; /* MSS saved before performing PMTU-D BlackHole detection */
u_int32_t t_pmtud_start_ts; /* Time of PMTUD blackhole detection */
struct{
u_int32_t rxduplicatebytes;
u_int32_t rxoutoforderbytes;
u_int32_t txretransmitbytes;
u_int16_t synrxtshift;
u_int16_t rxmitsyns;
u_int16_t unused_pad_to_8;
u_int32_t rxmitpkts;
uint32_t delayed_acks_sent;
uint32_t acks_delayed;
} t_stat;
u_int8_t t_syn_sent;
u_int8_t t_syn_rcvd;
u_int8_t t_notify_ack_count;
u_int8_t t_ecn_recv_ce_pkt; /* Received packet with CE-bit set (independent from last_ack_sent) */
u_int32_t t_cached_maxopd; /* default for MSS adjustment using link status report */
uint32_t bg_ssthresh; /* Slow start threshold until delay increases */
uint32_t t_flagsext; /* Another field to accommodate more flags */
#define TF_RXTFINDROP 0x1 /* Drop conn after retransmitting FIN 3 times */
#define TF_RCVUNACK_WAITSS 0x2 /* set when the receiver should not stretch acks */
#define TF_BWMEAS_INPROGRESS 0x4 /* Indicate BW meas is happening */
#define TF_MEASURESNDBW 0x8 /* Measure send bw on this connection */
#define TF_LAST_IS_PSH 0x10 /* Indicates whether the last packet in the rcv socket buffer had the PUSH-flag set */
#define TF_SACK_ENABLE 0x20 /* SACK is enabled */
#define TF_RECOMPUTE_RTT 0x40 /* recompute RTT after spurious retransmit */
#define TF_DETECT_READSTALL 0x80 /* Used to detect a stall during read operation */
#define TF_RECV_THROTTLE 0x100 /* Input throttling active */
#define TF_NOSTRETCHACK 0x200 /* ack every other packet */
#define TF_NOTIMEWAIT 0x800 /* Avoid going into time-wait */
#define TF_SENT_TLPROBE 0x1000 /* Sent data in PTO */
#define TF_PKTS_REORDERED 0x2000 /* Detected reordering */
#define TF_DELAY_RECOVERY 0x4000 /* delay fast recovery */
#define TF_FORCE 0x8000 /* force 1 byte out */
#define TF_DISABLE_STRETCHACK 0x10000 /* auto-disable stretch ack */
#define TF_NOBLACKHOLE_DETECTION 0x20000 /* Disable PMTU blackhole detection */
#define TF_RESCUE_RXT 0x80000 /* SACK rescue retransmit */
#define TF_CWND_NONVALIDATED 0x100000 /* cwnd non validated */
#define TF_IF_PROBING 0x200000 /* Trigger interface probe timeout */
#define TF_FASTOPEN 0x400000 /* TCP Fastopen is enabled */
#define TF_REASS_INPROG 0x800000 /* Reassembly is in progress */
#define TF_FASTOPEN_FORCE_ENABLE 0x1000000 /* Force-enable TCP Fastopen */
#define TF_USR_OUTPUT 0x2000000 /* In connect() or send() so tcp_output() can log */
#define TF_L4S_ENABLED 0x8000000 /* L4S was force enabled */
#define TF_L4S_DISABLED 0x10000000 /* L4S was force disabled */
#if TRAFFIC_MGT
/* Inter-arrival jitter related state */
uint32_t iaj_rcv_ts; /* tcp clock when the first packet was received */
int iaj_size; /* Size of packet for iaj measurement */
uint8_t iaj_small_pkt; /* Count of packets smaller than iaj_size */
uint8_t t_pipeack_ind; /* index for next pipeack sample */
uint16_t iaj_pktcnt; /* packet count, to avoid throttling initially */
uint32_t acc_iaj; /* Accumulated iaj */
uint32_t avg_iaj; /* Mean */
uint32_t std_dev_iaj; /* Standard deviation */
#endif /* TRAFFIC_MGT */
struct bwmeas *t_bwmeas; /* State for bandwidth measurement */
tcp_seq t_idleat; /* rcv_nxt at idle time */
uint8_t t_fin_sent;
uint8_t t_fin_rcvd;
uint8_t t_rst_sent;
uint8_t t_rst_rcvd;
TAILQ_ENTRY(tcpcb) t_twentry; /* link for time wait queue */
struct tcp_ccstate *t_ccstate; /* congestion control related state */
struct tcp_ccstate _t_ccstate; /* congestion control related state, non-allocated */
/* Tail loss probe related state */
tcp_seq t_tlphighrxt; /* snd_nxt after PTO */
u_int32_t t_tlpstart; /* timestamp at PTO */
/* DSACK data receiver state */
tcp_seq t_dsack_lseq; /* DSACK left sequence */
tcp_seq t_dsack_rseq; /* DSACK right sequence */
/* DSACK data sender state */
SLIST_HEAD(tcp_rxt_seghead, tcp_rxt_seg) t_rxt_segments;
uint32_t t_rxt_seg_count;
uint32_t t_rxt_seg_drop;
tcp_seq t_dsack_lastuna; /* snd_una when last recovery episode started */
/* state for congestion window validation (draft-ietf-tcpm-newcwv-07) */
#define TCP_PIPEACK_SAMPLE_COUNT 3
u_int32_t t_pipeack_sample[TCP_PIPEACK_SAMPLE_COUNT]; /* pipeack, bytes acked within RTT */
tcp_seq t_pipeack_lastuna; /* una when pipeack measurement started */
u_int32_t t_pipeack;
u_int32_t t_lossflightsize;
#if MPTCP
u_int32_t t_mpflags; /* flags for multipath TCP */
#define TMPF_PREESTABLISHED 0x00000001 /* conn in pre-established state */
#define TMPF_SND_KEYS 0x00000002 /* indicates that keys should be send */
#define TMPF_MPTCP_TRUE 0x00000004 /* negotiated MPTCP successfully */
/* UNUSED */
#define TMPF_SND_MPPRIO 0x00000010 /* send priority of subflow */
#define TMPF_SND_REM_ADDR 0x00000020 /* initiate address removal */
#define TMPF_RCVD_DACK 0x00000040 /* received a data-ack */
#define TMPF_JOINED_FLOW 0x00000080 /* Indicates additional flow */
#define TMPF_BACKUP_PATH 0x00000100 /* Indicates backup path */
#define TMPF_MPTCP_ACKNOW 0x00000200 /* Send Data ACK */
#define TMPF_SEND_DSN 0x00000400 /* Send DSN mapping */
#define TMPF_SEND_DFIN 0x00000800 /* Send Data FIN */
#define TMPF_RECV_DFIN 0x00001000 /* Recv Data FIN */
#define TMPF_SENT_JOIN 0x00002000 /* Sent Join */
#define TMPF_RECVD_JOIN 0x00004000 /* Received Join */
#define TMPF_RESET 0x00008000 /* Send RST */
#define TMPF_TCP_FALLBACK 0x00010000 /* Fallback to TCP */
#define TMPF_FASTCLOSERCV 0x00020000 /* Received Fastclose option */
#define TMPF_EMBED_DSN 0x00040000 /* tp has DSN mapping */
#define TMPF_MPTCP_READY 0x00080000 /* Can send DSS options on data */
#define TMPF_INFIN_SENT 0x00100000 /* Sent infinite mapping */
#define TMPF_SND_MPFAIL 0x00200000 /* Received mapping csum failure */
#define TMPF_SND_JACK 0x00400000 /* Send a Join-ACK */
#define TMPF_TFO_REQUEST 0x00800000 /* TFO Requested */
#define TMPF_MPTCP_ECHO_ADDR 0x01000000 /* MPTCP echoes add_addr */
#define TMPF_MPTCP_SIGNALS (TMPF_SND_MPPRIO | TMPF_SND_REM_ADDR | TMPF_SND_MPFAIL | TMPF_SND_JACK | TMPF_MPTCP_ECHO_ADDR)
tcp_seq t_mpuna; /* unacknowledged sequence */
struct mptcb *t_mptcb; /* pointer to MPTCP TCB */
struct mptsub *t_mpsub; /* pointer to the MPTCP subflow */
struct mpt_dsn_map t_rcv_map; /* Receive mapping list */
u_int8_t t_local_aid; /* Addr Id for authentication */
u_int8_t t_rem_aid; /* Addr ID of another subflow */
u_int8_t t_mprxtshift; /* join retransmission */
#endif /* MPTCP */
#define TFO_F_OFFER_COOKIE 0x01 /* We will offer a cookie */
#define TFO_F_COOKIE_VALID 0x02 /* The received cookie is valid */
#define TFO_F_COOKIE_REQ 0x04 /* Client requested a new cookie */
#define TFO_F_COOKIE_SENT 0x08 /* Client did send a cookie in the SYN */
#define TFO_F_SYN_LOSS 0x10 /* A SYN-loss triggered a fallback to regular TCP on the client-side */
#define TFO_F_NO_SNDPROBING 0x20 /* This network is guaranteed to support TFO in the upstream direction */
#define TFO_F_HEURISTIC_DONE 0x40 /* We have already marked this network as bad */
u_int8_t t_tfo_flags;
#define TFO_S_SYNDATA_RCV 0x01 /* SYN+data has been received */
#define TFO_S_COOKIEREQ_RECV 0x02 /* TFO-cookie request received */
#define TFO_S_COOKIE_SENT 0x04 /* TFO-cookie announced in SYN/ACK */
#define TFO_S_COOKIE_INVALID 0x08 /* Received TFO-cookie is invalid */
#define TFO_S_COOKIE_REQ 0x10 /* TFO-cookie requested within the SYN */
#define TFO_S_COOKIE_RCV 0x20 /* TFO-cookie received in SYN/ACK */
#define TFO_S_SYN_DATA_SENT 0x40 /* SYN+data sent */
#define TFO_S_SYN_DATA_ACKED 0x80 /* SYN+data has been acknowledged in SYN/ACK */
#define TFO_S_SYN_LOSS 0x0100 /* SYN+TFO has been lost - fallback to regular TCP */
#define TFO_S_COOKIE_WRONG 0x0200 /* Cookie we sent in the SYN was wrong */
#define TFO_S_NO_COOKIE_RCV 0x0400 /* We asked for a cookie but didn't get one */
#define TFO_S_HEURISTICS_DISABLE 0x0800 /* TFO-heuristics disabled it for this connection */
#define TFO_S_SEND_BLACKHOLE 0x1000 /* TFO got blackholed in the send direction */
#define TFO_S_RECV_BLACKHOLE 0x2000 /* TFO got blackholed in the recv direction */
#define TFO_S_ONE_BYTE_PROXY 0x4000 /* TFO failed because of a proxy acknowledging just one byte */
u_int16_t t_tfo_stats;
u_int8_t t_tfo_probes; /* TFO-probes we did send */
/*
* This here is the TFO-probing state-machine. Transitions are as follows:
*
* Current state: PROBE_NONE
* Event: SYN+DATA acknowledged
* Action: Transition to PROBE_PROBING and set keepalive-timer
*
* Current state: PROBE_PROBING (initial state)
* Event: Receive data
* Action: Transition to PROBE_NONE and cancel keepalive-timer
* Event: Receive ACK that does not indicate a hole
* Action: Transition to PROBE_NONE and cancel keepalive-timer
* Event: Receive ACK that indicates a hole
* Action: Transition to PROBE_WAIT_DATA and set a short timer
* to wait for the final segment.
* Event: Keepalive-timeout (did not receive any segment)
* Action: Signal ETIMEDOUT as with regular keepalive-timers
*
* Current state: PROBE_WAIT_DATA
* Event: Receive data
* Action: Transition to PROBE_NONE and cancel keepalive-timer
* Event: Data-timeout (did not receive the expected data)
* Action: Signal ENODATA up to the app and close everything.
*/
#define TFO_PROBE_NONE 0 /* Not probing now */
#define TFO_PROBE_PROBING 1 /* Sending out TCP-keepalives waiting for reply */
#define TFO_PROBE_WAIT_DATA 2 /* Received reply, waiting for data */
u_int8_t t_tfo_probe_state;
u_int32_t t_rcvoopack; /* out-of-order packets received */
u_int32_t t_pawsdrop; /* segments dropped due to PAWS */
u_int32_t t_sack_recovery_episode; /* SACK recovery episodes */
u_int32_t t_reordered_pkts; /* packets reorderd */
u_int32_t t_dsack_sent; /* Sent DSACK notification */
u_int32_t t_dsack_recvd; /* Received a valid DSACK option */
SLIST_HEAD(, tcp_notify_ack_marker) t_notify_ack; /* state for notifying data acknowledgements */
u_int32_t t_recv_throttle_ts; /* TS for start of recv throttle */
u_int32_t t_rxt_minimum_timeout; /* minimum retransmit timeout in ms */
uint32_t t_challengeack_last; /* last time challenge ACK was sent per sec */
uint32_t t_challengeack_count; /* # of challenge ACKs already sent per sec */
u_int32_t t_connect_time; /* time when the connection started */
uint64_t t_rcvwnd_limited_total_time;
uint64_t t_rcvwnd_limited_start_time;
uint32_t t_comp_gencnt; /* Current compression generation-count */
uint32_t t_comp_lastinc; /* Last time the gen-count was changed - should change every TCP_COMP_CHANGE_RATE ms */
#define TCP_COMP_CHANGE_RATE 5 /* Intervals at which we change the gencnt. Means that worst-case we send one ACK every TCP_COMP_CHANGE_RATE ms */
uint32_t t_ts_offset; /* Randomized timestamp offset to hide on-the-wire timestamp */
#define NCURR_RTT_HIST 4 /* Number of current RTT samples (k) */
uint32_t curr_rtt_hist[NCURR_RTT_HIST]; /* last k current RTT samples */
uint32_t curr_rtt_min; /* Minimum current RTT from last k samples */
uint32_t curr_rtt_index; /* Index for current RTT samples */
tcp_seq rcv_high; /* highest sequence number received */
uint32_t tsv_high; /* timestamp value of highest received sequence number */
struct tcp_rledbat_state t_rlstate; /* State used by rLedbat */
uint32_t rcv_srtt; /* receiver's SRTT, coarse when Timestamp not supported */
uint32_t rcv_rtt_est_ts; /* start of measurement for estimating RTT when Timestamp not supported */
uint32_t rcv_rtt_est_seq; /* expected sequence number for completion of 1RTT when Timestamp not supported */
uuid_t t_fsw_uuid;
uuid_t t_flow_uuid;
};
#define IN_FASTRECOVERY(tp) (tp->t_flags & TF_FASTRECOVERY)
#define SACK_ENABLED(tp) (tp->t_flagsext & TF_SACK_ENABLE)
/*
* If the connection is in a throttled state due to advisory feedback from
* the interface output queue, reset that state. We do this in favor
* of entering recovery because the data transfer during recovery
* should be just a trickle and it will help to improve performance.
* We also do not want to back off twice in the same RTT.
*/
#define ENTER_FASTRECOVERY(_tp_) do { \
(_tp_)->t_flags |= TF_FASTRECOVERY; \
if (INP_IS_FLOW_CONTROLLED((_tp_)->t_inpcb)) \
inp_reset_fc_state((_tp_)->t_inpcb); \
if (!SLIST_EMPTY(&tp->t_rxt_segments)) \
tcp_rxtseg_clean(tp); \
(_tp_)->t_new_dupacks = 0; \
} while(0)
#define EXIT_FASTRECOVERY(_tp_) do { \
(_tp_)->t_flags &= ~TF_FASTRECOVERY; \
(_tp_)->t_dupacks = 0; \
(_tp_)->t_new_dupacks = 0; \
(_tp_)->t_rexmtthresh = (uint8_t)tcprexmtthresh; \
(_tp_)->t_bytes_acked = 0; \
(_tp_)->ecn_flags &= ~TE_INRECOVERY; \
(_tp_)->t_timer[TCPT_PTO] = 0; \
(_tp_)->t_flagsext &= ~TF_RESCUE_RXT; \
(_tp_)->t_lossflightsize = 0; \
(_tp_)->sackhint.sack_bytes_acked = 0; \
} while(0)
/*
* When the number of duplicate acks received is less than
* the retransmit threshold, use Limited Transmit algorithm
*/
extern uint8_t tcprexmtthresh;
#define ALLOW_LIMITED_TRANSMIT(_tp_) \
((_tp_)->t_dupacks > 0 && \
(_tp_)->t_dupacks < (_tp_)->t_rexmtthresh && \
((_tp_)->t_flagsext & (TF_PKTS_REORDERED|TF_DELAY_RECOVERY)) \
!= (TF_PKTS_REORDERED|TF_DELAY_RECOVERY))
/*
* This condition is true if timestamp option is supported
* on a connection.
*/
#define TSTMP_SUPPORTED(_tp_) \
(((_tp_)->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP)) == \
(TF_REQ_TSTMP|TF_RCVD_TSTMP))
/*
* This condition is true if window scale option is supported
* on a connection
*/
#define TCP_WINDOW_SCALE_ENABLED(_tp_) \
(((_tp_)->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == \
(TF_RCVD_SCALE|TF_REQ_SCALE))
/* Is ECN negotiated end-to-end */
#define TCP_ECN_ENABLED(_tp_) \
(((_tp_)->ecn_flags & (TE_ECN_ON)) == (TE_ECN_ON))
extern int tcp_acc_ecn;
/*
* Accurate ECN feedback is enabled if
* 1. It is not disabled explicitly by tcp options
* 2. It is enabled either by sysctl or L4S toggle or A/B deployment or tcp_options,
* It supports ACE field as well as AccECN option for ECN feedback
*/
#define TCP_ACC_ECN_ENABLED(_tp_) \
(((_tp_)->t_flagsext & TF_L4S_DISABLED) == 0 && \
(tcp_acc_ecn == 1 || ((_tp_)->t_flagsext & TF_L4S_ENABLED)))
/* Accurate ECN is enabled and negotiated end-to-end */
#define TCP_ACC_ECN_ON(_tp_) \
(TCP_ACC_ECN_ENABLED(_tp_) && \
(((_tp_)->ecn_flags & (TE_ACC_ECN_ON)) == (TE_ACC_ECN_ON)))
/*
* Gives number of bytes acked by this ack
*/
#define BYTES_ACKED(_th_, _tp_) \
((_th_)->th_ack - (_tp_)->snd_una)
/* Returns true if a DSACK option should be sent */
#define TCP_SEND_DSACK_OPT(_tp_) \
((_tp_)->t_dsack_lseq > 0 && (_tp_)->t_dsack_rseq > 0)
/*
* Returns true if a DSACK sequence is within the max send window that will
* be accepted. In order to set a window to validate sequence numbers, the
* max send window within which a DSACK option is processed is limited.
*
* We need to choose a maximum window to check if the sequence number is
* within the window. One arbitrary choice is 256 * MSS because if the
* window is as large as 256 segments it might be big enough to ignore the
* DSACK option. Choosing a much larger limit means that the memory for
* retransmit segments can be held for a longer time.
*/
#define TCP_DSACK_MAX_SEND_WINDOW(_tp_) (MIN((_tp_)->snd_wnd, tcp_autosndbuf_max))
#define TCP_DSACK_SEQ_IN_WINDOW(_tp_, _seq_, _una_) \
(SEQ_LEQ((_seq_), (_tp_)->snd_max) && \
SEQ_GEQ((_seq_), ((_una_) - TCP_DSACK_MAX_SEND_WINDOW(_tp_))))
#define TCP_RESET_REXMT_STATE(_tp_) do { \
(_tp_)->t_rxtshift = 0; \
(_tp_)->t_rxtstart = 0; \
mptcp_reset_rexmit_state((_tp_)); \
} while(0);
#define TCP_IF_STATE_CHANGED(tp, probe_if_index) \
(probe_if_index > 0 && tp->t_inpcb->inp_last_outifp != NULL && \
probe_if_index == tp->t_inpcb->inp_last_outifp->if_index)
#define TCP_RLEDBAT_ENABLED(_tp) \
(tcp_rledbat == 1 && TSTMP_SUPPORTED(_tp))
#define TCP_RECV_BG(_so) \
(tcp_recv_bg == 1 || IS_TCP_RECV_BG(_so))
#define TCP_USE_RLEDBAT(_tp, _so) \
TCP_RLEDBAT_ENABLED(_tp) && TCP_RECV_BG(_so)
/*
* Structure to hold TCP options that are only used during segment
* processing (in tcp_input), but not held in the tcpcb.
* It's basically used to reduce the number of parameters
* to tcp_dooptions.
*/
struct tcpopt {
uint32_t to_flags; /* which options are present */
#define TOF_TS 0x0001 /* timestamp */
#define TOF_MSS 0x0010
#define TOF_SCALE 0x0020
#define TOF_SIGNATURE 0x0040 /* signature option present */
#define TOF_SIGLEN 0x0080 /* signature length valid (RFC2385) */
#define TOF_SACK 0x0100 /* Peer sent SACK option */
#define TOF_MPTCP 0x0200 /* MPTCP options to be dropped */
#define TOF_TFO 0x0400 /* TFO cookie option present */
#define TOF_TFOREQ 0x0800 /* TFO cookie request present */
uint32_t to_tsval;
uint32_t to_tsecr;
uint16_t to_mss;
uint8_t to_requested_s_scale;
uint8_t to_nsacks; /* number of SACK blocks */
u_char *to_sacks; /* pointer to the first SACK blocks */
u_char *to_tfo; /* pointer to the TFO cookie */
};
#define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb)
#define sototcpcb(so) (intotcpcb(sotoinpcb(so)))
/* TFO-specific defines */
#define TFO_COOKIE_LEN_MIN 4
#define TFO_COOKIE_LEN_DEFAULT 8
#define TFO_COOKIE_LEN_MAX 16
/*
* The initial retransmission should happen at rtt + 4 * rttvar.
* Because of the way we do the smoothing, srtt and rttvar
* will each average +1/2 tick of bias. When we compute
* the retransmit timer, we want 1/2 tick of rounding and
* 1 extra tick because of +-1/2 tick uncertainty in the
* firing of the timer. The bias will give us exactly the
* 1.5 tick we need. But, because the bias is
* statistical, we have to test that we don't drop below
* the minimum feasible timer (which is 2 ticks).
* This version of the macro adapted from a paper by Lawrence
* Brakmo and Larry Peterson which outlines a problem caused
* by insufficient precision in the original implementation,
* which results in inappropriately large RTO values for very
* fast networks.
*/
#define TCP_REXMTVAL(tp) \
max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \
+ (tp)->t_rttvar) >> TCP_DELTA_SHIFT)
/*
* Jaguar compatible TCP control block, for xtcpcb
* Does not have the old fields
*/
struct otcpcb {
#else
struct tseg_qent;
_TCPCB_LIST_HEAD(tsegqe_head, tseg_qent);
struct tcpcb {
#endif /* KERNEL_PRIVATE */
#if defined(KERNEL_PRIVATE)
u_int32_t t_segq;
#else
struct tsegqe_head t_segq;
#endif /* KERNEL_PRIVATE */
int t_dupacks; /* consecutive dup acks recd */
u_int32_t unused; /* unused now: was t_template */
int t_timer[TCPT_NTIMERS_EXT]; /* tcp timers */
_TCPCB_PTR(struct inpcb *) t_inpcb; /* back pointer to internet pcb */
int t_state; /* state of this connection */
u_int t_flags;
#define TF_ACKNOW 0x00001 /* ack peer immediately */
#define TF_DELACK 0x00002 /* ack, but try to delay it */
#define TF_NODELAY 0x00004 /* don't delay packets to coalesce */
#define TF_NOOPT 0x00008 /* don't use tcp options */
#define TF_SENTFIN 0x00010 /* have sent FIN */
#define TF_REQ_SCALE 0x00020 /* have/will request window scaling */
#define TF_RCVD_SCALE 0x00040 /* other side has requested scaling */
#define TF_REQ_TSTMP 0x00080 /* have/will request timestamps */
#define TF_RCVD_TSTMP 0x00100 /* a timestamp was received in SYN */
#define TF_SACK_PERMIT 0x00200 /* other side said I could SACK */
#define TF_NEEDSYN 0x00400 /* send SYN (implicit state) - unused but needed for backwards compatibility */
#define TF_NEEDFIN 0x00800 /* send FIN (implicit state) */
#define TF_NOPUSH 0x01000 /* don't push */
#define TF_REQ_CC 0x02000 /* have/will request CC */
#define TF_RCVD_CC 0x04000 /* a CC was received in SYN */
#define TF_SENDCCNEW 0x08000 /* Not implemented */
#define TF_MORETOCOME 0x10000 /* More data to be appended to sock */
#define TF_LQ_OVERFLOW 0x20000 /* listen queue overflow */
#define TF_RXWIN0SENT 0x40000 /* sent a receiver win 0 in response */
#define TF_SLOWLINK 0x80000 /* route is a on a modem speed link */
int t_force; /* 1 if forcing out a byte */
tcp_seq snd_una; /* send unacknowledged */
tcp_seq snd_max; /* highest sequence number sent;
* used to recognize retransmits
*/
tcp_seq snd_nxt; /* send next */
tcp_seq snd_up; /* send urgent pointer */
tcp_seq snd_wl1; /* window update seg seq number */
tcp_seq snd_wl2; /* window update seg ack number */
tcp_seq iss; /* initial send sequence number */
tcp_seq irs; /* initial receive sequence number */
tcp_seq rcv_nxt; /* receive next */
tcp_seq rcv_adv; /* advertised window */
u_int32_t rcv_wnd; /* receive window */
tcp_seq rcv_up; /* receive urgent pointer */
u_int32_t snd_wnd; /* send window */
u_int32_t snd_cwnd; /* congestion-controlled window */
u_int32_t snd_ssthresh; /* snd_cwnd size threshold for
* for slow start exponential to
* linear switch
*/
u_int t_maxopd; /* mss plus options */
u_int32_t t_rcvtime; /* time at which a packet was received */
u_int32_t t_starttime; /* time connection was established */
int t_rtttime; /* round trip time */
tcp_seq t_rtseq; /* sequence number being timed */
int t_rxtcur; /* current retransmit value (ticks) */
u_int t_maxseg; /* maximum segment size */
int t_srtt; /* smoothed round-trip time */
int t_rttvar; /* variance in round-trip time */
int t_rxtshift; /* log(2) of rexmt exp. backoff */
u_int t_rttmin; /* minimum rtt allowed */
u_int32_t t_rttupdated; /* number of times rtt sampled */
u_int32_t max_sndwnd; /* largest window peer has offered */
int t_softerror; /* possible error not yet reported */
/* out-of-band data */
char t_oobflags; /* have some */
char t_iobc; /* input character */
#define TCPOOB_HAVEDATA 0x01
#define TCPOOB_HADDATA 0x02
/* RFC 1323 variables */
u_char snd_scale; /* window scaling for send window */
u_char rcv_scale; /* window scaling for recv window */
u_char request_r_scale; /* pending window scaling */
u_char requested_s_scale;
u_int32_t ts_recent; /* timestamp echo data */
u_int32_t ts_recent_age; /* when last updated */
tcp_seq last_ack_sent;
/* RFC 1644 variables */
tcp_cc cc_send; /* send connection count */
tcp_cc cc_recv; /* receive connection count */
tcp_seq snd_recover; /* for use in fast recovery */
/* experimental */
u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
u_int32_t t_badrxtwin; /* window for retransmit recovery */
};
#define tcps_ecn_setup tcps_ecn_client_success
#define tcps_sent_cwr tcps_ecn_recv_ece
#define tcps_sent_ece tcps_ecn_sent_ece
/*
* TCP statistics.
* Many of these should be kept per connection,
* but that's inconvenient at the moment.
*/
struct tcpstat {
u_int32_t tcps_connattempt; /* connections initiated */
u_int32_t tcps_accepts; /* connections accepted */
u_int32_t tcps_connects; /* connections established */
u_int32_t tcps_drops; /* connections dropped */
u_int32_t tcps_conndrops; /* embryonic connections dropped */
u_int32_t tcps_closed; /* conn. closed (includes drops) */
u_int32_t tcps_segstimed; /* segs where we tried to get rtt */
u_int32_t tcps_rttupdated; /* times we succeeded */
u_int32_t tcps_delack; /* delayed acks sent */
u_int32_t tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
u_int32_t tcps_rexmttimeo; /* retransmit timeouts */
u_int32_t tcps_persisttimeo; /* persist timeouts */
u_int32_t tcps_keeptimeo; /* keepalive timeouts */
u_int32_t tcps_keepprobe; /* keepalive probes sent */
u_int32_t tcps_keepdrops; /* connections dropped in keepalive */
u_int32_t tcps_sndtotal; /* total packets sent */
u_int32_t tcps_sndpack; /* data packets sent */
u_int32_t tcps_sndbyte; /* data bytes sent */
u_int32_t tcps_sndrexmitpack; /* data packets retransmitted */
u_int32_t tcps_sndrexmitbyte; /* data bytes retransmitted */
u_int32_t tcps_sndacks; /* ack-only packets sent */
u_int32_t tcps_sndprobe; /* window probes sent */
u_int32_t tcps_sndurg; /* packets sent with URG only */
u_int32_t tcps_sndwinup; /* window update-only packets sent */
u_int32_t tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
u_int32_t tcps_rcvtotal; /* total packets received */
u_int32_t tcps_rcvpack; /* packets received in sequence */
u_int32_t tcps_rcvbyte; /* bytes received in sequence */
u_int32_t tcps_rcvbadsum; /* packets received with ccksum errs */
u_int32_t tcps_rcvbadoff; /* packets received with bad offset */
u_int32_t tcps_rcvmemdrop; /* packets dropped for lack of memory */
u_int32_t tcps_rcvshort; /* packets received too short */
u_int32_t tcps_rcvduppack; /* duplicate-only packets received */
u_int32_t tcps_rcvdupbyte; /* duplicate-only bytes received */
u_int32_t tcps_rcvpartduppack; /* packets with some duplicate data */
u_int32_t tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
u_int32_t tcps_rcvoopack; /* out-of-order packets received */
u_int32_t tcps_rcvoobyte; /* out-of-order bytes received */
u_int32_t tcps_rcvpackafterwin; /* packets with data after window */
u_int32_t tcps_rcvbyteafterwin; /* bytes rcvd after window */
u_int32_t tcps_rcvafterclose; /* packets rcvd after "close" */
u_int32_t tcps_rcvwinprobe; /* rcvd window probe packets */
u_int32_t tcps_rcvdupack; /* rcvd duplicate acks */
u_int32_t tcps_rcvacktoomuch; /* rcvd acks for unsent data */
u_int32_t tcps_rcvackpack; /* rcvd ack packets */
u_int32_t tcps_rcvackbyte; /* bytes acked by rcvd acks */
u_int32_t tcps_rcvwinupd; /* rcvd window update packets */
u_int32_t tcps_pawsdrop; /* segments dropped due to PAWS */
u_int32_t tcps_predack; /* times hdr predict ok for acks */
u_int32_t tcps_preddat; /* times hdr predict ok for data pkts */
u_int32_t tcps_pcbcachemiss;
u_int32_t tcps_cachedrtt; /* times cached RTT in route updated */
u_int32_t tcps_cachedrttvar; /* times cached rttvar updated */
u_int32_t tcps_cachedssthresh; /* times cached ssthresh updated */
u_int32_t tcps_usedrtt; /* times RTT initialized from route */
u_int32_t tcps_usedrttvar; /* times RTTVAR initialized from rt */
u_int32_t tcps_usedssthresh; /* times ssthresh initialized from rt*/
u_int32_t tcps_persistdrop; /* timeout in persist state */
u_int32_t tcps_badsyn; /* bogus SYN, e.g. premature ACK */
u_int32_t tcps_mturesent; /* resends due to MTU discovery */
u_int32_t tcps_listendrop; /* listen queue overflows */
u_int32_t tcps_synchallenge; /* challenge ACK due to bad SYN */
u_int32_t tcps_rstchallenge; /* challenge ACK due to bad RST */
/* new stats from FreeBSD 5.4 sync up */
u_int32_t tcps_minmssdrops; /* average minmss too low drops */
u_int32_t tcps_sndrexmitbad; /* unnecessary packet retransmissions */
u_int32_t tcps_badrst; /* ignored RSTs in the window */
u_int32_t tcps_sc_added; /* entry added to syncache */
u_int32_t tcps_sc_retransmitted; /* syncache entry was retransmitted */
u_int32_t tcps_sc_dupsyn; /* duplicate SYN packet */
u_int32_t tcps_sc_dropped; /* could not reply to packet */
u_int32_t tcps_sc_completed; /* successful extraction of entry */
u_int32_t tcps_sc_bucketoverflow; /* syncache per-bucket limit hit */
u_int32_t tcps_sc_cacheoverflow; /* syncache cache limit hit */
u_int32_t tcps_sc_reset; /* RST removed entry from syncache */
u_int32_t tcps_sc_stale; /* timed out or listen socket gone */
u_int32_t tcps_sc_aborted; /* syncache entry aborted */
u_int32_t tcps_sc_badack; /* removed due to bad ACK */
u_int32_t tcps_sc_unreach; /* ICMP unreachable received */
u_int32_t tcps_sc_zonefail; /* zalloc() failed */
u_int32_t tcps_sc_sendcookie; /* SYN cookie sent */
u_int32_t tcps_sc_recvcookie; /* SYN cookie received */
u_int32_t tcps_hc_added; /* entry added to hostcache */
u_int32_t tcps_hc_bucketoverflow; /* hostcache per bucket limit hit */
/* SACK related stats */
u_int32_t tcps_sack_recovery_episode; /* SACK recovery episodes */
u_int32_t tcps_sack_rexmits; /* SACK rexmit segments */
u_int32_t tcps_sack_rexmit_bytes; /* SACK rexmit bytes */
u_int32_t tcps_sack_rcv_blocks; /* SACK blocks (options) received */
u_int32_t tcps_sack_send_blocks; /* SACK blocks (options) sent */
u_int32_t tcps_sack_sboverflow; /* SACK sendblock overflow */
u_int32_t tcps_bg_rcvtotal; /* total background packets received */
u_int32_t tcps_rxtfindrop; /* drop conn after retransmitting FIN */
u_int32_t tcps_fcholdpacket; /* packets withheld because of flow control */
u_int32_t tcps_limited_txt; /* Limited transmit used */
u_int32_t tcps_early_rexmt; /* Early retransmit used */
u_int32_t tcps_sack_ackadv; /* Cumulative ack advanced along with sack */
/* Checksum related stats */
u_int32_t tcps_rcv_swcsum; /* tcp swcksum (inbound), packets */
u_int32_t tcps_rcv_swcsum_bytes; /* tcp swcksum (inbound), bytes */
u_int32_t tcps_rcv6_swcsum; /* tcp6 swcksum (inbound), packets */
u_int32_t tcps_rcv6_swcsum_bytes; /* tcp6 swcksum (inbound), bytes */
u_int32_t tcps_snd_swcsum; /* tcp swcksum (outbound), packets */
u_int32_t tcps_snd_swcsum_bytes; /* tcp swcksum (outbound), bytes */
u_int32_t tcps_snd6_swcsum; /* tcp6 swcksum (outbound), packets */
u_int32_t tcps_snd6_swcsum_bytes; /* tcp6 swcksum (outbound), bytes */
u_int32_t tcps_unused_1;
u_int32_t tcps_unused_2;
u_int32_t tcps_unused_3;
/* MPTCP Related stats */
u_int32_t tcps_invalid_mpcap; /* Invalid MPTCP capable opts */
u_int32_t tcps_invalid_joins; /* Invalid MPTCP joins */
u_int32_t tcps_mpcap_fallback; /* TCP fallback in primary */
u_int32_t tcps_join_fallback; /* No MPTCP in secondary */
u_int32_t tcps_estab_fallback; /* DSS option dropped */
u_int32_t tcps_invalid_opt; /* Catchall error stat */
u_int32_t tcps_mp_outofwin; /* Packet lies outside the
* shared recv window */
u_int32_t tcps_mp_reducedwin; /* Reduced subflow window */
u_int32_t tcps_mp_badcsum; /* Bad DSS csum */
u_int32_t tcps_mp_oodata; /* Out of order data */
u_int32_t tcps_mp_switches; /* number of subflow switch */
u_int32_t tcps_mp_rcvtotal; /* number of rcvd packets */
u_int32_t tcps_mp_rcvbytes; /* number of bytes received */
u_int32_t tcps_mp_sndpacks; /* number of data packs sent */
u_int32_t tcps_mp_sndbytes; /* number of bytes sent */
u_int32_t tcps_join_rxmts; /* join ack retransmits */
u_int32_t tcps_tailloss_rto; /* RTO due to tail loss */
u_int32_t tcps_reordered_pkts; /* packets reorderd */
u_int32_t tcps_recovered_pkts; /* recovered after loss */
u_int32_t tcps_pto; /* probe timeout */
u_int32_t tcps_rto_after_pto; /* RTO after a probe */
u_int32_t tcps_tlp_recovery; /* TLP induced fast recovery */
u_int32_t tcps_tlp_recoverlastpkt; /* TLP recoverd last pkt */
u_int32_t tcps_ecn_client_success; /* client-side connection negotiated ECN */
u_int32_t tcps_ecn_recv_ece; /* ECE received, sent CWR */
u_int32_t tcps_ecn_sent_ece; /* Sent ECE notification */
u_int32_t tcps_detect_reordering; /* Detect pkt reordering */
u_int32_t tcps_delay_recovery; /* Delay fast recovery */
u_int32_t tcps_avoid_rxmt; /* Retransmission was avoided */
u_int32_t tcps_unnecessary_rxmt; /* Retransmission was not needed */
u_int32_t tcps_nostretchack; /* disabled stretch ack algorithm on a connection */
u_int32_t tcps_rescue_rxmt; /* SACK rescue retransmit */
u_int32_t tcps_pto_in_recovery; /* rescue retransmit in fast recovery */
u_int32_t tcps_pmtudbh_reverted; /* PMTU Blackhole detection, segment size reverted */
/* DSACK related statistics */
u_int32_t tcps_dsack_disable; /* DSACK disabled due to n/w duplication */
u_int32_t tcps_dsack_ackloss; /* ignore DSACK due to ack loss */
u_int32_t tcps_dsack_badrexmt; /* DSACK based bad rexmt recovery */
u_int32_t tcps_dsack_sent; /* Sent DSACK notification */
u_int32_t tcps_dsack_recvd; /* Received a valid DSACK option */
u_int32_t tcps_dsack_recvd_old; /* Received an out of window DSACK option */
/* MPTCP Subflow selection stats */
u_int32_t tcps_mp_sel_symtomsd; /* By symptomsd */
u_int32_t tcps_mp_sel_rtt; /* By RTT comparison */
u_int32_t tcps_mp_sel_rto; /* By RTO comparison */
u_int32_t tcps_mp_sel_peer; /* By peer's output pattern */
u_int32_t tcps_mp_num_probes; /* Number of probes sent */
u_int32_t tcps_mp_verdowngrade; /* MPTCP version downgrade */
u_int32_t tcps_drop_after_sleep; /* drop after long AP sleep */
u_int32_t tcps_probe_if; /* probe packets after interface availability */
u_int32_t tcps_probe_if_conflict; /* Can't send probe packets for interface */
u_int32_t tcps_ecn_client_setup; /* Attempted ECN setup from client side */
u_int32_t tcps_ecn_server_setup; /* Attempted ECN setup from server side */
u_int32_t tcps_ecn_server_success; /* server-side connection negotiated ECN */
u_int32_t tcps_ecn_ace_syn_not_ect; /* received AccECN SYN packet with Not-ECT */
u_int32_t tcps_ecn_ace_syn_ect1; /* received AccECN SYN packet with ECT1 */
u_int32_t tcps_ecn_ace_syn_ect0; /* received AccECN SYN packet with ECT0 */
u_int32_t tcps_ecn_ace_syn_ce; /* received AccECN SYN packet with CE */
u_int32_t tcps_ecn_lost_synack; /* Lost SYN-ACK with ECN setup */
u_int32_t tcps_ecn_lost_syn; /* Lost SYN with ECN setup */
u_int32_t tcps_ecn_not_supported; /* Server did not support ECN setup */
u_int32_t tcps_ecn_recv_ce; /* Received CE from the network */
u_int32_t tcps_ecn_ace_recv_ce; /* CE count received in ACE field */
u_int32_t tcps_ecn_conn_recv_ce; /* Number of connections received CE atleast once */
u_int32_t tcps_ecn_conn_recv_ece; /* Number of connections received ECE atleast once */
u_int32_t tcps_ecn_conn_plnoce; /* Number of connections that received no CE and sufferred packet loss */
u_int32_t tcps_ecn_conn_pl_ce; /* Number of connections that received CE and sufferred packet loss */
u_int32_t tcps_ecn_conn_nopl_ce; /* Number of connections that received CE and sufferred no packet loss */
u_int32_t tcps_ecn_fallback_synloss; /* Number of times we did fall back due to SYN-Loss */
u_int32_t tcps_ecn_fallback_reorder; /* Number of times we fallback because we detected the PAWS-issue */
u_int32_t tcps_ecn_fallback_ce; /* Number of times we fallback because we received too many CEs */
/* TFO-related statistics */
u_int32_t tcps_tfo_syn_data_rcv; /* Received a SYN+data with valid cookie */
u_int32_t tcps_tfo_cookie_req_rcv;/* Received a TFO cookie-request */
u_int32_t tcps_tfo_cookie_sent; /* Offered a TFO-cookie to the client */
u_int32_t tcps_tfo_cookie_invalid;/* Received an invalid TFO-cookie */
u_int32_t tcps_tfo_cookie_req; /* Cookie requested with the SYN */
u_int32_t tcps_tfo_cookie_rcv; /* Cookie received in a SYN/ACK */
u_int32_t tcps_tfo_syn_data_sent; /* SYN+data+cookie sent */
u_int32_t tcps_tfo_syn_data_acked;/* SYN+data has been acknowledged */
u_int32_t tcps_tfo_syn_loss; /* SYN+TFO has been lost and we fallback */
u_int32_t tcps_tfo_blackhole; /* TFO got blackholed by a middlebox. */
u_int32_t tcps_tfo_cookie_wrong; /* TFO-cookie we sent was wrong */
u_int32_t tcps_tfo_no_cookie_rcv; /* We asked for a cookie but didn't get one */
u_int32_t tcps_tfo_heuristics_disable; /* TFO got disabled due to heuristics */
u_int32_t tcps_tfo_sndblackhole; /* TFO got blackholed in the sending direction */
u_int32_t tcps_mss_to_default; /* Change MSS to default using link status report */
u_int32_t tcps_mss_to_medium; /* Change MSS to medium using link status report */
u_int32_t tcps_mss_to_low; /* Change MSS to low using link status report */
u_int32_t tcps_ecn_fallback_droprst; /* ECN fallback caused by connection drop due to RST */
u_int32_t tcps_ecn_fallback_droprxmt; /* ECN fallback due to drop after multiple retransmits */
u_int32_t tcps_ecn_fallback_synrst; /* ECN fallback due to rst after syn */
u_int32_t tcps_mptcp_rcvmemdrop; /* MPTCP packets dropped for lack of memory */
u_int32_t tcps_mptcp_rcvduppack; /* MPTCP duplicate-only packets received */
u_int32_t tcps_mptcp_rcvpackafterwin; /* MPTCP packets with data after window */
/* TCP timer statistics */
u_int32_t tcps_timer_drift_le_1_ms; /* Timer drift less or equal to 1 ms */
u_int32_t tcps_timer_drift_le_10_ms; /* Timer drift less or equal to 10 ms */
u_int32_t tcps_timer_drift_le_20_ms; /* Timer drift less or equal to 20 ms */
u_int32_t tcps_timer_drift_le_50_ms; /* Timer drift less or equal to 50 ms */
u_int32_t tcps_timer_drift_le_100_ms; /* Timer drift less or equal to 100 ms */
u_int32_t tcps_timer_drift_le_200_ms; /* Timer drift less or equal to 200 ms */
u_int32_t tcps_timer_drift_le_500_ms; /* Timer drift less or equal to 500 ms */
u_int32_t tcps_timer_drift_le_1000_ms; /* Timer drift less or equal to 1000 ms */
u_int32_t tcps_timer_drift_gt_1000_ms; /* Timer drift greater than 1000 ms */
u_int32_t tcps_mptcp_handover_attempt; /* Total number of MPTCP-attempts using handover mode */
u_int32_t tcps_mptcp_interactive_attempt; /* Total number of MPTCP-attempts using interactive mode */
u_int32_t tcps_mptcp_aggregate_attempt; /* Total number of MPTCP-attempts using aggregate mode */
u_int32_t tcps_mptcp_fp_handover_attempt; /* Same as previous three but only for first-party apps */
u_int32_t tcps_mptcp_fp_interactive_attempt;
u_int32_t tcps_mptcp_fp_aggregate_attempt;
u_int32_t tcps_mptcp_heuristic_fallback; /* Total number of MPTCP-connections that fell back due to heuristics */
u_int32_t tcps_mptcp_fp_heuristic_fallback; /* Same as previous but for first-party apps */
u_int32_t tcps_mptcp_handover_success_wifi; /* Total number of successfull handover-mode connections that *started* on WiFi */
u_int32_t tcps_mptcp_handover_success_cell; /* Total number of successfull handover-mode connections that *started* on Cell */
u_int32_t tcps_mptcp_interactive_success; /* Total number of interactive-mode connections that negotiated MPTCP */
u_int32_t tcps_mptcp_aggregate_success; /* Same as previous but for aggregate */
u_int32_t tcps_mptcp_fp_handover_success_wifi; /* Same as previous four, but for first-party apps */
u_int32_t tcps_mptcp_fp_handover_success_cell;
u_int32_t tcps_mptcp_fp_interactive_success;
u_int32_t tcps_mptcp_fp_aggregate_success;
u_int32_t tcps_mptcp_handover_cell_from_wifi; /* Total number of connections that use cell in handover-mode (coming from WiFi) */
u_int32_t tcps_mptcp_handover_wifi_from_cell; /* Total number of connections that use WiFi in handover-mode (coming from cell) */
u_int32_t tcps_mptcp_interactive_cell_from_wifi; /* Total number of connections that use cell in interactive mode (coming from WiFi) */
u_int64_t tcps_mptcp_handover_cell_bytes; /* Total number of bytes sent on cell in handover-mode (on new subflows, ignoring initial one) */
u_int64_t tcps_mptcp_interactive_cell_bytes; /* Same as previous but for interactive */
u_int64_t tcps_mptcp_aggregate_cell_bytes;
u_int64_t tcps_mptcp_handover_all_bytes; /* Total number of bytes sent in handover */
u_int64_t tcps_mptcp_interactive_all_bytes;
u_int64_t tcps_mptcp_aggregate_all_bytes;
u_int32_t tcps_mptcp_back_to_wifi; /* Total number of connections that succeed to move traffic away from cell (when starting on cell) */
u_int32_t tcps_mptcp_wifi_proxy; /* Total number of new subflows that fell back to regular TCP on cell */
u_int32_t tcps_mptcp_cell_proxy; /* Total number of new subflows that fell back to regular TCP on WiFi */
/* TCP offload statistics */
u_int32_t tcps_ka_offload_drops; /* Keep alive drops for timeout reported by firmware */
u_int32_t tcps_mptcp_triggered_cell; /* Total number of times an MPTCP-connection triggered cell bringup */
u_int32_t tcps_fin_timeout_drops;
};
struct tcpstat_local {
u_int64_t badformat;
u_int64_t unspecv6;
u_int64_t synfin;
u_int64_t badformatipsec;
u_int64_t noconnnolist;
u_int64_t noconnlist;
u_int64_t listbadsyn;
u_int64_t icmp6unreach;
u_int64_t deprecate6;
u_int64_t ooopacket;
u_int64_t rstinsynrcv;
u_int64_t dospacket;
u_int64_t cleanup;
u_int64_t synwindow;
};
#pragma pack(4)
/*
* TCB structure exported to user-land via sysctl(3).
* Evil hack: declare only if in_pcb.h and sys/socketvar.h have been
* included. Not all of our clients do.
*/
struct xtcpcb {
u_int32_t xt_len;
#ifdef KERNEL_PRIVATE
struct inpcb_compat xt_inp;
#else
struct inpcb xt_inp;
#endif
#ifdef KERNEL_PRIVATE
struct otcpcb xt_tp;
#else
struct tcpcb xt_tp;
#endif
struct xsocket xt_socket;
u_quad_t xt_alignment_hack;
};
#if XNU_TARGET_OS_OSX || KERNEL || !(TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR)
struct xtcpcb64 {
u_int32_t xt_len;
struct xinpcb64 xt_inpcb;
u_int64_t t_segq;
int t_dupacks; /* consecutive dup acks recd */
int t_timer[TCPT_NTIMERS_EXT]; /* tcp timers */
int t_state; /* state of this connection */
u_int t_flags;
int t_force; /* 1 if forcing out a byte */
tcp_seq snd_una; /* send unacknowledged */
tcp_seq snd_max; /* highest sequence number sent;
* used to recognize retransmits
*/
tcp_seq snd_nxt; /* send next */
tcp_seq snd_up; /* send urgent pointer */
tcp_seq snd_wl1; /* window update seg seq number */
tcp_seq snd_wl2; /* window update seg ack number */
tcp_seq iss; /* initial send sequence number */
tcp_seq irs; /* initial receive sequence number */
tcp_seq rcv_nxt; /* receive next */
tcp_seq rcv_adv; /* advertised window */
u_int32_t rcv_wnd; /* receive window */
tcp_seq rcv_up; /* receive urgent pointer */
u_int32_t snd_wnd; /* send window */
u_int32_t snd_cwnd; /* congestion-controlled window */
u_int32_t snd_ssthresh; /* snd_cwnd size threshold for
* for slow start exponential to
* linear switch
*/
u_int t_maxopd; /* mss plus options */
u_int32_t t_rcvtime; /* time at which a packet was received */
u_int32_t t_starttime; /* time connection was established */
int t_rtttime; /* round trip time */
tcp_seq t_rtseq; /* sequence number being timed */
int t_rxtcur; /* current retransmit value (ticks) */
u_int t_maxseg; /* maximum segment size */
int t_srtt; /* smoothed round-trip time */
int t_rttvar; /* variance in round-trip time */
int t_rxtshift; /* log(2) of rexmt exp. backoff */
u_int t_rttmin; /* minimum rtt allowed */
u_int32_t t_rttupdated; /* number of times rtt sampled */
u_int32_t max_sndwnd; /* largest window peer has offered */
int t_softerror; /* possible error not yet reported */
/* out-of-band data */
char t_oobflags; /* have some */
char t_iobc; /* input character */
/* RFC 1323 variables */
u_char snd_scale; /* window scaling for send window */
u_char rcv_scale; /* window scaling for recv window */
u_char request_r_scale; /* pending window scaling */
u_char requested_s_scale;
u_int32_t ts_recent; /* timestamp echo data */
u_int32_t ts_recent_age; /* when last updated */
tcp_seq last_ack_sent;
/* RFC 1644 variables */
tcp_cc cc_send; /* send connection count */
tcp_cc cc_recv; /* receive connection count */
tcp_seq snd_recover; /* for use in fast recovery */
/* experimental */
u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
u_int32_t t_badrxtwin; /* window for retransmit recovery */
u_quad_t xt_alignment_hack;
};
#endif /* XNU_TARGET_OS_OSX || KERNEL || !(TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR) */
#ifdef PRIVATE
struct xtcpcb_n {
u_int32_t xt_len;
u_int32_t xt_kind; /* XSO_TCPCB */
u_int64_t t_segq;
int t_dupacks; /* consecutive dup acks recd */
int t_timer[TCPT_NTIMERS_EXT]; /* tcp timers */
int t_state; /* state of this connection */
u_int t_flags;
int t_force; /* 1 if forcing out a byte */
tcp_seq snd_una; /* send unacknowledged */
tcp_seq snd_max; /* highest sequence number sent;
* used to recognize retransmits
*/
tcp_seq snd_nxt; /* send next */
tcp_seq snd_up; /* send urgent pointer */
tcp_seq snd_wl1; /* window update seg seq number */
tcp_seq snd_wl2; /* window update seg ack number */
tcp_seq iss; /* initial send sequence number */
tcp_seq irs; /* initial receive sequence number */
tcp_seq rcv_nxt; /* receive next */
tcp_seq rcv_adv; /* advertised window */
u_int32_t rcv_wnd; /* receive window */
tcp_seq rcv_up; /* receive urgent pointer */
u_int32_t snd_wnd; /* send window */
u_int32_t snd_cwnd; /* congestion-controlled window */
u_int32_t snd_ssthresh; /* snd_cwnd size threshold for
* for slow start exponential to
* linear switch
*/
u_int t_maxopd; /* mss plus options */
u_int32_t t_rcvtime; /* time at which a packet was received */
u_int32_t t_starttime; /* time connection was established */
int t_rtttime; /* round trip time */
tcp_seq t_rtseq; /* sequence number being timed */
int t_rxtcur; /* current retransmit value (ticks) */
u_int t_maxseg; /* maximum segment size */
int t_srtt; /* smoothed round-trip time */
int t_rttvar; /* variance in round-trip time */
int t_rxtshift; /* log(2) of rexmt exp. backoff */
u_int t_rttmin; /* minimum rtt allowed */
u_int32_t t_rttupdated; /* number of times rtt sampled */
u_int32_t max_sndwnd; /* largest window peer has offered */
int t_softerror; /* possible error not yet reported */
/* out-of-band data */
char t_oobflags; /* have some */
char t_iobc; /* input character */
/* RFC 1323 variables */
u_char snd_scale; /* window scaling for send window */
u_char rcv_scale; /* window scaling for recv window */
u_char request_r_scale; /* pending window scaling */
u_char requested_s_scale;
u_int32_t ts_recent; /* timestamp echo data */
u_int32_t ts_recent_age; /* when last updated */
tcp_seq last_ack_sent;
/* RFC 1644 variables */
tcp_cc cc_send; /* send connection count */
tcp_cc cc_recv; /* receive connection count */
tcp_seq snd_recover; /* for use in fast recovery */
/* experimental */
u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
};
/*
* The rtt measured is in milliseconds as the timestamp granularity is
* a millisecond. The smoothed round-trip time and estimated variance
* are stored as fixed point numbers scaled by the values below.
* For convenience, these scales are also used in smoothing the average
* (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed).
* With these scales, srtt has 5 bits to the right of the binary point,
* and thus an "ALPHA" of 0.875. rttvar has 4 bits to the right of the
* binary point, and is smoothed with an ALPHA of 0.75.
*/
#define TCP_RTT_SCALE 32 /* multiplier for srtt; 3 bits frac. */
#define TCP_RTT_SHIFT 5 /* shift for srtt; 5 bits frac. */
#define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 4 bits */
#define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 4 bits */
#define TCP_DELTA_SHIFT 2 /* see tcp_input.c */
/*
* TCP structure with information that gives insight into forward progress on an interface,
* exported to user-land via sysctl(3).
*/
struct xtcpprogress_indicators {
u_int32_t xp_numflows; /* Total number of flows */
u_int32_t xp_conn_probe_fails; /* Count of connection failures */
u_int32_t xp_read_probe_fails; /* Count of read probe failures */
u_int32_t xp_write_probe_fails; /* Count of write failures */
u_int32_t xp_recentflows; /* Total of "recent" flows */
u_int32_t xp_recentflows_unacked; /* Total of "recent" flows with unacknowledged data */
u_int64_t xp_recentflows_rxbytes; /* Total of "recent" flows received bytes */
u_int64_t xp_recentflows_txbytes; /* Total of "recent" flows transmitted bytes */
u_int64_t xp_recentflows_rxooo; /* Total of "recent" flows received out of order bytes */
u_int64_t xp_recentflows_rxdup; /* Total of "recent" flows received duplicate bytes */
u_int64_t xp_recentflows_retx; /* Total of "recent" flows retransmitted bytes */
u_int64_t xp_reserved1; /* Expansion */
u_int64_t xp_reserved2; /* Expansion */
u_int64_t xp_reserved3; /* Expansion */
u_int64_t xp_reserved4; /* Expansion */
};
struct tcpprogressreq {
u_int64_t ifindex; /* Interface index for progress indicators */
u_int64_t recentflow_maxduration; /* In mach_absolute_time, max duration for flow to be counted as "recent" */
u_int64_t filter_flags; /* Optional additional filtering, values are interface properties per ntstat.h */
u_int64_t xp_reserved2; /* Expansion */
};
struct tcpprobereq {
u_int64_t ifindex; /* Optional interface index for TCP keep-alive probing */
u_int64_t enable; /* Flag to enable or disable probing (1=on, 0=off)*/
u_int64_t filter_flags; /* Optional flags for filtering interfaces per ntstat.h (NSTAT_IFNET_IS_*) */
u_int32_t reserved; /* Expansion */
u_int32_t reserved2; /* Expansion */
};
#endif /* PRIVATE */
#pragma pack()
/*
* Names for TCP sysctl objects
*/
#define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */
#define TCPCTL_DO_RFC1644 2 /* use RFC-1644 extensions */
#define TCPCTL_MSSDFLT 3 /* MSS default */
#define TCPCTL_STATS 4 /* statistics (read-only) */
#define TCPCTL_RTTDFLT 5 /* default RTT estimate */
#define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */
#define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */
#define TCPCTL_SENDSPACE 8 /* send buffer space */
#define TCPCTL_RECVSPACE 9 /* receive buffer space */
#define TCPCTL_KEEPINIT 10 /* timeout for establishing syn */
#define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */
#define TCPCTL_DELACKTIME 12 /* time before sending delayed ACK */
#define TCPCTL_V6MSSDFLT 13 /* MSS default for IPv6 */
#define TCPCTL_MAXID 14
#ifdef BSD_KERNEL_PRIVATE
#include <sys/bitstring.h>
#define TCP_PKTLIST_CLEAR(tp) { \
(tp)->t_pktlist_head = (tp)->t_pktlist_tail = NULL; \
(tp)->t_lastchain = (tp)->t_pktlist_sentlen = 0; \
}
extern int tcp_TCPTV_MIN;
#ifdef SYSCTL_DECL
SYSCTL_DECL(_net_inet_tcp);
#endif /* SYSCTL_DECL */
extern struct inpcbhead tcb; /* head of queue of active tcpcb's */
extern struct inpcbinfo tcbinfo;
extern struct tcpstat tcpstat; /* tcp statistics */
extern int tcp_mssdflt; /* XXX */
extern int tcp_minmss;
#define TCP_FASTOPEN_SERVER 0x01
#define TCP_FASTOPEN_CLIENT 0x02
extern int tcp_tfo_halfcnt;
extern int tcp_tfo_backlog;
extern int tcp_fastopen;
extern int ss_fltsz_local;
extern int target_qdelay;
extern u_int32_t tcp_now; /* for RFC 1323 timestamps */
extern struct timeval tcp_uptime;
extern lck_spin_t tcp_uptime_lock;
extern int tcp_delack_enabled;
extern int maxseg_unacked;
KALLOC_TYPE_DECLARE(tcp_reass_zone);
KALLOC_TYPE_DECLARE(tcp_rxt_seg_zone);
extern int tcp_ecn_outbound;
extern int tcp_ecn_inbound;
extern uint32_t tcp_do_autorcvbuf;
extern uint32_t tcp_autorcvbuf_max;
extern int tcp_recv_bg;
extern int tcp_do_ack_compression;
extern int tcp_randomize_timestamps;
extern int tcp_rledbat;
extern int tcp_use_min_curr_rtt;
extern int tcp_do_timestamps;
/*
* Dummy value used for when there is no flow and we want to ensure that compression
* can happen.
*/
#define TCP_ACK_COMPRESSION_DUMMY 1
extern int tcp_do_better_lr;
extern int tcp_cubic_minor_fixes;
extern int tcp_cubic_rfc_compliant;
extern int tcp_flow_control_response;
extern int tcp_reass_total_qlen;
struct protosw;
struct domain;
struct tcp_respond_args {
unsigned int ifscope;
unsigned int nocell:1,
noexpensive:1,
awdl_unrestricted:1,
intcoproc_allowed:1,
keep_alive:1,
noconstrained:1,
management_allowed:1;
};
void tcp_canceltimers(struct tcpcb *);
struct tcpcb *
tcp_close(struct tcpcb *);
void tcp_ctlinput(int, struct sockaddr *, void *, struct ifnet *);
int tcp_ctloutput(struct socket *, struct sockopt *);
struct tcpcb *
tcp_drop(struct tcpcb *, int);
void tcp_drain(void);
void tcp_getrt_rtt(struct tcpcb *tp, struct rtentry *rt);
void tcp_init(struct protosw *, struct domain *);
void tcp_input(struct mbuf *, int);
void tcp_mss(struct tcpcb *, int, unsigned int);
uint32_t tcp_ceil(double a);
uint32_t tcp_round_to(uint32_t val, uint32_t round);
uint32_t tcp_round_up(uint32_t val, uint32_t base);
int tcp_mssopt(struct tcpcb *);
void tcp_drop_syn_sent(struct inpcb *, int);
void tcp_mtudisc(struct inpcb *, int);
struct tcpcb *
tcp_newtcpcb(struct inpcb *);
int tcp_output(struct tcpcb *);
void tcp_respond(struct tcpcb *, void *, struct tcphdr *, struct mbuf *,
tcp_seq, tcp_seq, uint8_t, struct tcp_respond_args *);
struct rtentry *
tcp_rtlookup(struct inpcb *, unsigned int);
void tcp_setpersist(struct tcpcb *);
void tcp_gc(struct inpcbinfo *);
void tcp_itimer(struct inpcbinfo *ipi);
void tcp_check_timer_state(struct tcpcb *tp);
void tcp_run_timerlist(void *arg1, void *arg2);
void tcp_sched_timers(struct tcpcb *tp);
struct tcptemp *tcp_maketemplate(struct tcpcb *, struct mbuf **);
void tcp_fillheaders(struct mbuf *, struct tcpcb *, void *, void *);
struct tcpcb *tcp_timers(struct tcpcb *, int);
void tcp_trace(int, int, struct tcpcb *, void *, struct tcphdr *, int);
void tcp_fill_info(struct tcpcb *, struct tcp_info *);
void tcp_sack_doack(struct tcpcb *, struct tcpopt *, struct tcphdr *,
u_int32_t *, uint32_t *);
extern boolean_t tcp_sack_process_dsack(struct tcpcb *, struct tcpopt *,
struct tcphdr *);
int tcp_detect_bad_rexmt(struct tcpcb *, struct tcphdr *, struct tcpopt *,
u_int32_t rxtime);
void tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend);
void tcp_clean_sackreport(struct tcpcb *tp);
uint32_t tcp_sack_adjust(struct tcpcb *tp);
struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt);
void tcp_sack_partialack(struct tcpcb *, struct tcphdr *);
void tcp_free_sackholes(struct tcpcb *tp);
void tcp_sack_lost_rexmit(struct tcpcb *tp);
int32_t tcp_sbspace(struct tcpcb *tp);
void tcp_set_tso(struct tcpcb *tp, struct ifnet *ifp);
void tcp_set_ecn(struct tcpcb *tp, struct ifnet *ifp);
uint8_t tcp_get_ace(struct tcphdr *th);
int tcp_flight_size(struct tcpcb *tp);
void tcp_reset_stretch_ack(struct tcpcb *tp);
extern void tcp_get_ports_used(ifnet_t ifp, int, u_int32_t, bitstr_t *);
uint32_t tcp_count_opportunistic(unsigned int ifindex, u_int32_t flags);
uint32_t tcp_find_anypcb_byaddr(struct ifaddr *ifa);
void tcp_set_max_rwinscale(struct tcpcb *tp, struct socket *so);
struct bwmeas* tcp_bwmeas_alloc(struct tcpcb *tp);
void tcp_bwmeas_free(struct tcpcb *tp);
extern int32_t timer_diff(uint32_t t1, uint32_t toff1, uint32_t t2, uint32_t toff2);
extern void tcp_set_background_cc(struct socket *);
extern void tcp_set_foreground_cc(struct socket *);
extern void tcp_set_recv_bg(struct socket *);
extern void tcp_clear_recv_bg(struct socket *);
extern boolean_t tcp_sack_byte_islost(struct tcpcb *tp);
#define IS_TCP_RECV_BG(_so) \
((_so)->so_flags1 & SOF1_TRAFFIC_MGT_TCP_RECVBG)
#if TRAFFIC_MGT
#define CLEAR_IAJ_STATE(_tp_) (_tp_)->iaj_rcv_ts = 0
void reset_acc_iaj(struct tcpcb *tp);
#endif /* TRAFFIC_MGT */
int tcp_lock(struct socket *, int, void *);
int tcp_unlock(struct socket *, int, void *);
void calculate_tcp_clock(void);
extern void tcp_keepalive_reset(struct tcpcb *);
extern uint32_t get_base_rtt(struct tcpcb *tp);
#ifdef _KERN_LOCKS_H_
lck_mtx_t * tcp_getlock(struct socket *, int);
#else
void * tcp_getlock(struct socket *, int);
#endif
extern int faster_mcopy;
extern struct pr_usrreqs tcp_usrreqs;
extern u_int32_t tcp_sendspace;
extern u_int32_t tcp_recvspace;
tcp_seq tcp_new_isn(struct tcpcb *);
extern int tcp_input_checksum(int, struct mbuf *, struct tcphdr *, int, int);
extern void tcp_getconninfo(struct socket *, struct conninfo_tcp *);
extern void add_to_time_wait(struct tcpcb *, uint32_t delay);
extern void add_to_time_wait_now(struct tcpcb *tp, uint32_t delay);
extern void tcp_pmtud_revert_segment_size(struct tcpcb *tp);
extern void tcp_rxtseg_insert(struct tcpcb *, tcp_seq, tcp_seq);
extern struct tcp_rxt_seg *tcp_rxtseg_find(struct tcpcb *, tcp_seq, tcp_seq);
extern void tcp_rxtseg_set_spurious(struct tcpcb *tp, tcp_seq start, tcp_seq end);
extern void tcp_rxtseg_clean(struct tcpcb *);
extern boolean_t tcp_rxtseg_detect_bad_rexmt(struct tcpcb *, tcp_seq);
extern boolean_t tcp_rxtseg_dsack_for_tlp(struct tcpcb *);
extern u_int32_t tcp_rxtseg_total_size(struct tcpcb *tp);
extern void tcp_rexmt_save_state(struct tcpcb *tp);
extern void tcp_interface_send_probe(u_int16_t if_index_available);
extern void tcp_probe_connectivity(struct ifnet *ifp, u_int32_t enable);
extern void tcp_get_connectivity_status(struct tcpcb *,
struct tcp_conn_status *);
extern void tcp_clear_keep_alive_offload(struct socket *so);
extern void tcp_fill_keepalive_offload_frames(struct ifnet *,
struct ifnet_keepalive_offload_frame *, u_int32_t, size_t, u_int32_t *);
extern int tcp_notify_kao_timeout(ifnet_t ifp,
struct ifnet_keepalive_offload_frame *frame);
extern boolean_t tfo_enabled(const struct tcpcb *tp);
extern void tcp_disable_tfo(struct tcpcb *tp);
extern void tcp_tfo_gen_cookie(struct inpcb *inp, u_char *out, size_t blk_size);
#define TCP_FASTOPEN_KEYLEN 16
extern int tcp_freeq(struct tcpcb *tp);
extern errno_t tcp_notify_ack_id_valid(struct tcpcb *, struct socket *, u_int32_t);
extern errno_t tcp_add_notify_ack_marker(struct tcpcb *, u_int32_t);
extern void tcp_notify_ack_free(struct tcpcb *);
extern void tcp_notify_acknowledgement(struct tcpcb *, struct socket *);
extern void tcp_get_notify_ack_count(struct tcpcb *,
struct tcp_notify_ack_complete *);
extern void tcp_get_notify_ack_ids(struct tcpcb *tp,
struct tcp_notify_ack_complete *);
extern void tcp_update_mss_locked(struct socket *, struct ifnet *);
extern int get_tcp_inp_list(struct inpcb **, int, inp_gen_t);
extern bool tcp_notify_ack_active(struct socket *so);
extern void tcp_set_finwait_timeout(struct tcpcb *);
#if MPTCP
extern uint16_t mptcp_output_csum(struct mbuf *m, uint64_t dss_val,
uint32_t sseq, uint16_t dlen);
extern int mptcp_adj_mss(struct tcpcb *, boolean_t);
extern void mptcp_insert_rmap(struct tcpcb *tp, struct mbuf *m, struct tcphdr *th);
extern int dump_mptcp_reass_qlen(char *, int);
#endif
extern int dump_tcp_reass_qlen(char *, int);
extern uint32_t tcp_reass_qlen_space(struct socket *);
__private_extern__ void tcp_update_stats_per_flow(
struct ifnet_stats_per_flow *, struct ifnet *);
#define TCP_ACK_STRATEGY_LEGACY 0
#define TCP_ACK_STRATEGY_MODERN 1
extern int tcp_ack_strategy;
#if SKYWALK
void tcp_add_fsw_flow(struct tcpcb *, struct ifnet *);
void tcp_del_fsw_flow(struct tcpcb *);
#else /* !SKYWALK */
#define tcp_add_fsw_flow(...)
#define tcp_del_fsw_flow(...)
#endif /* !SKYWALK */
#endif /* BSD_KERNEL_PRIVATE */
#endif /* _NETINET_TCP_VAR_H_ */