-/* ip.h 6.1 83/07/29 */
+/*
+ * Copyright (c) 1982, 1986 Regents of the University of California.
+ * All rights reserved. The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ *
+ * @(#)ip.h 7.1 (Berkeley) 6/5/86
+ */
/*
* Definitions for internet protocol version 4.
* Definitions for options.
*/
#define IPOPT_COPIED(o) ((o)&0x80)
-#define IPOPT_CLASS(o) ((o)&0x40)
-#define IPOPT_NUMBER(o) ((o)&0x3f)
+#define IPOPT_CLASS(o) ((o)&0x60)
+#define IPOPT_NUMBER(o) ((o)&0x1f)
#define IPOPT_CONTROL 0x00
-#define IPOPT_RESERVED1 0x10
-#define IPOPT_DEBMEAS 0x20
-#define IPOPT_RESERVED2 0x30
+#define IPOPT_RESERVED1 0x20
+#define IPOPT_DEBMEAS 0x40
+#define IPOPT_RESERVED2 0x60
#define IPOPT_EOL 0 /* end of option list */
#define IPOPT_NOP 1 /* no operation */
#define IPOPT_SATID 136 /* satnet id */
#define IPOPT_SSRR 137 /* strict source route */
+/*
+ * Offsets to fields in options other than EOL and NOP.
+ */
+#define IPOPT_OPTVAL 0 /* option ID */
+#define IPOPT_OLEN 1 /* option length */
+#define IPOPT_OFFSET 2 /* offset within option */
+#define IPOPT_MINOFF 4 /* min value of above */
+
/*
* Time stamp option structure.
*/
*/
#define MAXTTL 255 /* maximum time to live (seconds) */
#define IPFRAGTTL 15 /* time to live for frag chains */
-#define IPTTLDEC 5 /* subtracted when forwarding */
+#define IPTTLDEC 1 /* subtracted when forwarding */
+
+#define IP_MSS 576 /* default maximum segment size */