X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/53a5409ebc57f165caf4d645703d954ada29be2c..a2cdf9f6b08eceef2637b965669f0e87065b27fb:/usr/src/sys/netinet/tcp.h

diff --git a/usr/src/sys/netinet/tcp.h b/usr/src/sys/netinet/tcp.h
index 648ec8768b..b945f85de9 100644
--- a/usr/src/sys/netinet/tcp.h
+++ b/usr/src/sys/netinet/tcp.h
@@ -1,38 +1,87 @@
-/* tcp.h 1.15 81/11/14 */
-
 /*
- * Tcp header.  Fits over the ip header after option removed.
+ * Copyright (c) 1982, 1986, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * %sccs.include.redist.c%
  *
- * SHOULD MAKE A CLEAN HEADER FOR USE BY USERS.
+ *	@(#)tcp.h	8.1 (Berkeley) %G%
  */
-struct tcpiphdr {
-	struct	tcpiphdr *t_next;		/* -> next tcp on rcv chain */
-	struct	tcpiphdr *t_prev;		/* -> prev tcp on rcv chain */
-	u_char	t_x1;			/* (unused) */
-	u_char	t_pr;			/* protocol */
-/* by rights, t_len should be a u_short, but this makes operations */
-/* on it very dangerous as comparisons become unsigned and comparing */
-/* against negative numbers then fails... we don't expect any > 32767 */
-/* byte segments, so pragmatically delcare it to be a short */
-	short	t_len;			/* seg length */
-	struct	ip_addr t_s;		/* source internet address */
-	struct	ip_addr t_d;		/* destination internet address */
-	u_short	t_src;			/* source port */
-	u_short	t_dst;			/* destination port */
-	seq_t	t_seq;			/* sequence number */
-	seq_t	t_ackno;		/* acknowledgement number */
-#define	t_end(x) (x->t_seq + x->t_len - 1)
-	u_char
-		t_x2:4,			/* (unused) */
-		t_off:4;		/* data offset */
+#ifndef BYTE_ORDER
+/*
+ * Definitions for byte order,
+ * according to byte significance from low address to high.
+ */
+#define	LITTLE_ENDIAN	1234	/* least-significant byte first (vax) */
+#define	BIG_ENDIAN	4321	/* most-significant byte first (IBM, net) */
+#define	PDP_ENDIAN	3412	/* LSB first in word, MSW first in long (pdp) */
+
+#ifdef vax
+#define	BYTE_ORDER	LITTLE_ENDIAN
+#else
+#define	BYTE_ORDER	BIG_ENDIAN	/* mc68000, tahoe, most others */
+#endif
+#endif BYTE_ORDER
+
+typedef	u_long	tcp_seq;
+/*
+ * TCP header.
+ * Per RFC 793, September, 1981.
+ */
+struct tcphdr {
+	u_short	th_sport;		/* source port */
+	u_short	th_dport;		/* destination port */
+	tcp_seq	th_seq;			/* sequence number */
+	tcp_seq	th_ack;			/* acknowledgement number */
+#if BYTE_ORDER == LITTLE_ENDIAN
+	u_char	th_x2:4,		/* (unused) */
+		th_off:4;		/* data offset */
+#endif
+#if BYTE_ORDER == BIG_ENDIAN
+	u_char	th_off:4,		/* data offset */
+		th_x2:4;		/* (unused) */
+#endif
 	u_char	th_flags;
-#define	TH_FIN	001
-#define	TH_SYN	002
-#define	TH_RST	004
-#define	TH_EOL	010
-#define	TH_ACK	020
-#define	TH_URG	040
-	u_short	t_win;			/* window */
-	u_short	t_sum;			/* checksum */
-	u_short	t_urp;			/* urgent pointer */
+#define	TH_FIN	0x01
+#define	TH_SYN	0x02
+#define	TH_RST	0x04
+#define	TH_PUSH	0x08
+#define	TH_ACK	0x10
+#define	TH_URG	0x20
+	u_short	th_win;			/* window */
+	u_short	th_sum;			/* checksum */
+	u_short	th_urp;			/* urgent pointer */
 };
+
+#define	TCPOPT_EOL		0
+#define	TCPOPT_NOP		1
+#define	TCPOPT_MAXSEG		2
+#define    TCPOLEN_MAXSEG		4
+#define TCPOPT_WINDOW		3
+#define    TCPOLEN_WINDOW		3
+#define TCPOPT_SACK_PERMITTED	4		/* Experimental */
+#define    TCPOLEN_SACK_PERMITTED	2
+#define TCPOPT_SACK		5		/* Experimental */
+#define TCPOPT_TIMESTAMP	8
+#define    TCPOLEN_TIMESTAMP		10
+#define    TCPOLEN_TSTAMP_APPA		(TCPOLEN_TIMESTAMP+2) /* appendix A */
+
+#define TCPOPT_TSTAMP_HDR	\
+    (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)
+
+/*
+ * Default maximum segment size for TCP.
+ * With an IP MSS of 576, this is 536,
+ * but 512 is probably more convenient.
+ * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
+ */
+#define	TCP_MSS	512
+
+#define	TCP_MAXWIN	65535	/* largest value for (unscaled) window */
+
+#define TCP_MAX_WINSHIFT	14	/* maximum window shift */
+
+/*
+ * User-settable options (used with setsockopt).
+ */
+#define	TCP_NODELAY	0x01	/* don't delay send to coalesce packets */
+#define	TCP_MAXSEG	0x02	/* set maximum segment size */