xref: /freebsd/usr.sbin/ppp/hdlc.h (revision 2a4a1db342263067035ce69a4017c645da63455d)
1 /*-
2  * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
3  *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
4  *                           Internet Initiative Japan, Inc (IIJ)
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 /*
32  *  Definition for Async HDLC
33  */
34 #define HDLC_SYN 0x7e		/* SYNC character */
35 #define HDLC_ESC 0x7d		/* Escape character */
36 #define HDLC_XOR 0x20		/* Modifier value */
37 
38 #define	HDLC_ADDR 0xff
39 #define	HDLC_UI	  0x03
40 /*
41  *  Definition for HDLC Frame Check Sequence
42  */
43 #define INITFCS 0xffff		/* Initial value for FCS computation */
44 #define GOODFCS 0xf0b8		/* Good FCS value */
45 
46 #define	DEF_MRU		1500
47 #define	MAX_MRU		2048
48 #define	MIN_MRU		296
49 
50 #define	DEF_MTU		0	/* whatever peer says */
51 #define	MAX_MTU		2048
52 #define	MIN_MTU		296
53 
54 struct physical;
55 struct link;
56 struct lcp;
57 struct bundle;
58 struct mbuf;
59 struct cmdargs;
60 
61 struct hdlc {
62   struct pppTimer ReportTimer;
63 
64   struct {
65     int badfcs;
66     int badaddr;
67     int badcommand;
68     int unknownproto;
69   } laststats, stats;
70 
71   struct {
72     struct lcp *owner;			/* parent LCP */
73     struct pppTimer timer;		/* When to send */
74     int method;				/* bit-mask for LQM_* from lqr.h */
75 
76     u_int32_t OutPackets;		/* Packets sent by me */
77     u_int32_t OutOctets;		/* Octets sent by me */
78     u_int32_t SaveInPackets;		/* Packets received from peer */
79     u_int32_t SaveInDiscards;		/* Discards */
80     u_int32_t SaveInErrors;		/* Errors */
81     u_int32_t SaveInOctets;		/* Octets received from peer */
82 
83     struct {
84       u_int32_t OutLQRs;		/* LQRs sent by me */
85       u_int32_t SaveInLQRs;		/* LQRs received from peer */
86       struct lqrdata peer;		/* Last LQR from peer */
87       int peer_timeout;			/* peers max lqr timeout */
88       int resent;			/* Resent last packet `resent' times */
89     } lqr;
90 
91     struct {
92       u_int32_t seq_sent;		/* last echo sent */
93       u_int32_t seq_recv;		/* last echo received */
94     } echo;
95   } lqm;
96 };
97 
98 
99 extern void hdlc_Init(struct hdlc *, struct lcp *);
100 extern void hdlc_StartTimer(struct hdlc *);
101 extern void hdlc_StopTimer(struct hdlc *);
102 extern int hdlc_ReportStatus(struct cmdargs const *);
103 extern const char *hdlc_Protocol2Nam(u_short);
104 extern void hdlc_DecodePacket(struct bundle *, u_short, struct mbuf *,
105                               struct link *);
106 
107 extern u_short hdlc_Fcs(u_char *, size_t);
108 extern int hdlc_Detect(u_char const **, int, int);
109 extern int hdlc_WrapperOctets(struct lcp *, u_short);
110 
111 extern struct layer hdlclayer;
112