X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/378393581903b274cb7a4d18e0d978071a6b592d..6601e61aa18bf4f09af135ff61fc7f4771d23b06:/bsd/netinet/tcp_var.h

diff --git a/bsd/netinet/tcp_var.h b/bsd/netinet/tcp_var.h
index 08b897f6c..d8c69adee 100644
--- a/bsd/netinet/tcp_var.h
+++ b/bsd/netinet/tcp_var.h
@@ -84,6 +84,23 @@ extern int	tcp_reass_qsize;
 MALLOC_DECLARE(M_TSEGQ);
 #endif
 
+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 */
+	TAILQ_ENTRY(sackhole) scblink;	/* scoreboard linkage */
+};
+
+struct sackhint {
+	struct sackhole	*nexthole;
+	int	sack_bytes_rexmit;
+};
+
 struct tcptemp {
 	u_char	tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */
 	struct	tcphdr tt_t;
@@ -126,6 +143,13 @@ struct tcpcb {
 #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 */
+
 	int	t_force;		/* 1 if forcing out a byte */
 
 	tcp_seq	snd_una;		/* send unacknowledged */
@@ -202,8 +226,30 @@ struct tcpcb {
 	tcp_seq snd_high;		/* for use in NewReno Fast Recovery */
 	tcp_seq snd_high_prev;	/* snd_high prior to retransmit */
 
+	tcp_seq	snd_recover_prev;	/* snd_recover prior to retransmit */
+	u_char	snd_limited;		/* segments limited transmitted */
+/* anti DoS counters */
+	u_long	rcv_second;		/* start of interval second */
+/* SACK related state */
+	int	sack_enable;		/* enable SACK for this connection */
+	int	snd_numholes;		/* number of holes seen by sender */
+
+	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 */
+	tcp_seq sack_newdata;		/* New data xmitted in this recovery
+   					   episode starts at this seq number */
+	struct sackhint	sackhint;	/* SACK scoreboard hint */
+	int	t_rttlow;		/* smallest observerved RTT */
 };
 
+#define IN_FASTRECOVERY(tp)	(tp->t_flags & TF_FASTRECOVERY)
+#define ENTER_FASTRECOVERY(tp)	tp->t_flags |= TF_FASTRECOVERY
+#define EXIT_FASTRECOVERY(tp)	tp->t_flags &= ~TF_FASTRECOVERY
+
+
 /*
  * Structure to hold TCP options that are only used during segment
  * processing (in tcp_input), but not held in the tcpcb.
@@ -211,16 +257,19 @@ struct tcpcb {
  * to tcp_dooptions.
  */
 struct tcpopt {
-	u_long	to_flag;		/* which options are present */
+	u_long	to_flags;		/* which options are present */
 #define TOF_TS		0x0001		/* timestamp */
-#define TOF_CC		0x0002		/* CC and CCnew are exclusive */
-#define TOF_CCNEW	0x0004
-#define	TOF_CCECHO	0x0008
-	u_long	to_tsval;
-	u_long	to_tsecr;
-	tcp_cc	to_cc;		/* holds CC or CCnew */
-	tcp_cc	to_ccecho;
-	u_short 	reserved;		/* unused now: was to_maxseg */
+#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 */
+	u_long		to_tsval;
+	u_long		to_tsecr;
+	u_int16_t	to_mss;
+	u_int8_t	to_requested_s_scale;
+	u_int8_t	to_nsacks;	/* number of SACK blocks */
+	u_char		*to_sacks;	/* pointer to the first SACK blocks */
 };
 
 /*
@@ -455,6 +504,15 @@ struct	tcpstat {
 	u_long	tcps_badsyn;		/* bogus SYN, e.g. premature ACK */
 	u_long	tcps_mturesent;		/* resends due to MTU discovery */
 	u_long	tcps_listendrop;	/* listen queue overflows */
+
+	/* SACK related stats */
+	u_long	tcps_sack_recovery_episode; /* SACK recovery episodes */
+	u_long  tcps_sack_rexmits;	    /* SACK rexmit segments   */
+	u_long  tcps_sack_rexmit_bytes;	    /* SACK rexmit bytes      */
+	u_long  tcps_sack_rcv_blocks;	    /* SACK blocks (options) received */
+	u_long  tcps_sack_send_blocks;	    /* SACK blocks (options) sent     */
+	u_long  tcps_sack_sboverflow;	    /* SACK sendblock overflow   */
+
 };
 
 /*
@@ -532,6 +590,7 @@ extern	u_long tcp_now;		/* for RFC 1323 timestamps */
 extern	int tcp_delack_enabled;
 #endif /* __APPLE__ */
 
+extern	int tcp_do_sack;	/* SACK enabled/disabled */
 
 void	 tcp_canceltimers(struct tcpcb *);
 struct tcpcb *
@@ -566,6 +625,15 @@ void	 tcp_fillheaders(struct tcpcb *, void *, void *);
 struct tcpcb *
 	 tcp_timers(struct tcpcb *, int);
 void	 tcp_trace(int, int, struct tcpcb *, void *, struct tcphdr *, int);
+
+void	 tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend);
+void	 tcp_clean_sackreport(struct tcpcb *tp);
+void	 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);
+
+
 int	 tcp_lock (struct socket *, int, int);
 int	 tcp_unlock (struct socket *, int, int);
 #ifdef _KERN_LOCKS_H_