xref: /freebsd/usr.sbin/ppp/hdlc.h (revision 42d4d396689ff18f91456f636cf531b2f116e79b)
1 /*
2  *	    Written by Toshiharu OHNO (tony-o@iij.ad.jp)
3  *
4  *   Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd.
5  *
6  * Redistribution and use in source and binary forms are permitted
7  * provided that the above copyright notice and this paragraph are
8  * duplicated in all such forms and that any documentation,
9  * advertising materials, and other materials related to such
10  * distribution and use acknowledge that the software was developed
11  * by the Internet Initiative Japan.  The name of the
12  * IIJ may not be used to endorse or promote products derived
13  * from this software without specific prior written permission.
14  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
16  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
17  *
18  * $Id: hdlc.h,v 1.14.2.3 1998/02/02 19:32:07 brian Exp $
19  *
20  *	TODO:
21  */
22 
23 /*
24  *  Definition for Async HDLC
25  */
26 #define HDLC_SYN 0x7e		/* SYNC character */
27 #define HDLC_ESC 0x7d		/* Escape character */
28 #define HDLC_XOR 0x20		/* Modifier value */
29 
30 #define	HDLC_ADDR 0xff
31 #define	HDLC_UI	  0x03
32 /*
33  *  Definition for HDLC Frame Check Sequence
34  */
35 #define INITFCS 0xffff		/* Initial value for FCS computation */
36 #define GOODFCS 0xf0b8		/* Good FCS value */
37 
38 #define	DEF_MRU		1500
39 #define	MAX_MRU		2048
40 #define	MIN_MRU		296
41 
42 #define	DEF_MTU		0	/* whatever peer says */
43 #define	MAX_MTU		2048
44 #define	MIN_MTU		296
45 
46 /*
47  *  Output priority
48  */
49 /* PRI_NORMAL and PRI_FAST have meaning only on the IP queue.
50  * All IP frames have the same priority once they are compressed.
51  * IP frames stay on the IP queue till they can be sent on the
52  * link. They are compressed at that time.
53 */
54 #define	PRI_NORMAL	0	/* Normal priority */
55 #define	PRI_FAST	1	/* Fast (interractive) */
56 #define	PRI_LINK	1	/* Urgent (LQR packets) */
57 #define	PRI_MAX		1
58 
59 extern u_char EscMap[33];
60 
61 struct physical;
62 struct link;
63 
64 extern void HdlcInit(void);
65 extern void HdlcErrorCheck(void);
66 extern void HdlcInput(struct bundle *, struct mbuf *, struct physical *);
67 extern void HdlcOutput(struct link *, int, u_short, struct mbuf *bp);
68 extern u_short HdlcFcs(u_short, u_char *, int);
69 extern int ReportHdlcStatus(struct cmdargs const *);
70 extern int ReportProtStatus(struct cmdargs const *);
71 extern u_char *HdlcDetect(struct physical *, u_char *, int);
72