X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/1c79356b52d46aa6b508fb032f5ae709b1f2897b..5eebf7385fedb1517b66b53c28e5aa6bb0a2be50:/bsd/netinet/tcp.h

diff --git a/bsd/netinet/tcp.h b/bsd/netinet/tcp.h
index 5cd425b9c..30479bd88 100644
--- a/bsd/netinet/tcp.h
+++ b/bsd/netinet/tcp.h
@@ -52,10 +52,12 @@
  * SUCH DAMAGE.
  *
  *	@(#)tcp.h	8.1 (Berkeley) 6/10/93
+ * $FreeBSD: src/sys/netinet/tcp.h,v 1.13.2.3 2001/03/01 22:08:42 jlemon Exp $
  */
 
 #ifndef _NETINET_TCP_H_
 #define _NETINET_TCP_H_
+#include <sys/appleapiopts.h>
 
 typedef	u_int32_t tcp_seq;
 typedef u_int32_t tcp_cc;		/* connection count per rfc1644 */
@@ -87,7 +89,9 @@ struct tcphdr {
 #define	TH_PUSH	0x08
 #define	TH_ACK	0x10
 #define	TH_URG	0x20
-#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG)
+#define	TH_ECE	0x40
+#define	TH_CWR	0x80
+#define	TH_FLAGS	(TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG|TH_ECE|TH_CWR)
 
 	u_short	th_win;			/* window */
 	u_short	th_sum;			/* checksum */
@@ -119,12 +123,23 @@ struct tcphdr {
 
 /*
  * Default maximum segment size for TCP.
- * With an IP MSS of 576, this is 536,
+ * With an IP MTU 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
 
+/*
+ * TCP_MINMSS is defined to be 216 which is fine for the smallest
+ * link MTU (256 bytes, SLIP interface) in the Internet.
+ * However it is very unlikely to come across such low MTU interfaces
+ * these days (anno dato 2004).
+ * Probably it can be set to 512 without ill effects. But we play safe.
+ * See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
+ * Setting this to "0" disables the minmss check.
+ */
+#define	TCP_MINMSS 216
+
 /*
  * Default maximum segment size for TCP6.
  * With an IP6 MSS of 1280, this is 1220,
@@ -138,6 +153,8 @@ struct tcphdr {
 
 #define TCP_MAX_WINSHIFT	14	/* maximum window shift */
 
+#define TCP_MAXBURST		4 	/* maximum segments in a burst */
+
 #define TCP_MAXHLEN	(0xf<<2)	/* max length of header in bytes */
 #define TCP_MAXOLEN	(TCP_MAXHLEN - sizeof(struct tcphdr))
 					/* max space left for options */
@@ -149,5 +166,6 @@ struct tcphdr {
 #define	TCP_MAXSEG	0x02	/* set maximum segment size */
 #define TCP_NOPUSH	0x04	/* don't push last block of write */
 #define TCP_NOOPT	0x08	/* don't use TCP options */
+#define TCP_KEEPALIVE	0x10	/* idle time used when SO_KEEPALIVE is enabled */
 
 #endif