fsm.h revision 134789 
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: head/usr.sbin/ppp/fsm.h 134789 2004-09-05 01:46:52Z brian $
29 */
30
31/*
32 *  State of machine
33 */
34#define	ST_INITIAL	0
35#define	ST_STARTING	1
36#define	ST_CLOSED	2
37#define	ST_STOPPED	3
38#define	ST_CLOSING	4
39#define	ST_STOPPING	5
40#define	ST_REQSENT	6
41#define	ST_ACKRCVD	7
42#define	ST_ACKSENT	8
43#define	ST_OPENED	9
44
45#define	ST_MAX		10
46#define	ST_UNDEF	-1
47
48#define	MODE_REQ	0
49#define	MODE_NAK	1
50#define	MODE_REJ	2
51#define	MODE_NOP	3
52#define	MODE_ACK	4	/* pseudo mode for ccp negotiations */
53
54#define	OPEN_PASSIVE	-1
55
56#define FSM_REQ_TIMER	1
57#define FSM_TRM_TIMER	2
58
59#define FSM_OPTLEN	100
60
61struct fsm;
62
63struct fsm_retry {
64  u_int timeout;                             /* FSM retry frequency */
65  u_int maxreq;                              /* Max Config REQ retries */
66  u_int maxtrm;                              /* Max Term REQ retries */
67};
68
69struct fsm_decode {
70  u_char ack[FSM_OPTLEN], *ackend;
71  u_char nak[FSM_OPTLEN], *nakend;
72  u_char rej[FSM_OPTLEN], *rejend;
73};
74
75struct fsm_callbacks {
76  int (*LayerUp)(struct fsm *);                 /* Layer is now up (tlu) */
77  void (*LayerDown)(struct fsm *);              /* About to come down (tld) */
78  void (*LayerStart)(struct fsm *);             /* Layer about to start (tls) */
79  void (*LayerFinish)(struct fsm *);            /* Layer now down (tlf) */
80  void (*InitRestartCounter)(struct fsm *, int);/* Set fsm timer load */
81  void (*SendConfigReq)(struct fsm *);          /* Send REQ please */
82  void (*SentTerminateReq)(struct fsm *);       /* Term REQ just sent */
83  void (*SendTerminateAck)(struct fsm *, u_char); /* Send Term ACK please */
84  void (*DecodeConfig)(struct fsm *, u_char *, u_char *, int,
85                       struct fsm_decode *);    /* Deal with incoming data */
86  int (*RecvResetReq)(struct fsm *fp);          /* Reset output */
87  void (*RecvResetAck)(struct fsm *fp, u_char); /* Reset input */
88};
89
90struct fsm_parent {
91  void (*LayerStart) (void *, struct fsm *);         /* tls */
92  void (*LayerUp) (void *, struct fsm *);            /* tlu */
93  void (*LayerDown) (void *, struct fsm *);          /* tld */
94  void (*LayerFinish) (void *, struct fsm *);        /* tlf */
95  void *object;
96};
97
98struct link;
99struct bundle;
100
101struct fsm {
102  const char *name;		/* Name of protocol */
103  u_short proto;		/* Protocol number */
104  u_short min_code;
105  u_short max_code;
106  int open_mode;		/* Delay before config REQ (-1 forever) */
107  unsigned state;		/* State of the machine */
108  u_char reqid;			/* Next request id */
109  int restart;			/* Restart counter value */
110
111  struct {
112    int reqs;			/* Max config REQs before a close() */
113    int naks;			/* Max config NAKs before a close() */
114    int rejs;			/* Max config REJs before a close() */
115  } more;
116
117  struct pppTimer FsmTimer;	/* Restart Timer */
118  struct pppTimer OpenTimer;	/* Delay before opening */
119
120  /*
121   * This timer times the ST_STOPPED state out after the given value
122   * (specified via "set stopped ...").  Although this isn't specified in the
123   * rfc, the rfc *does* say that "the application may use higher level
124   * timers to avoid deadlock". The StoppedTimer takes effect when the other
125   * side ABENDs rather than going into ST_ACKSENT (and sending the ACK),
126   * causing ppp to time out and drop into ST_STOPPED.  At this point,
127   * nothing will change this state :-(
128   */
129  struct pppTimer StoppedTimer;
130  int LogLevel;
131
132  /* The link layer active with this FSM (may be our bundle below) */
133  struct link *link;
134
135  /* Our high-level link */
136  struct bundle *bundle;
137
138  const struct fsm_parent *parent;
139  const struct fsm_callbacks *fn;
140};
141
142struct fsmheader {
143  u_char code;			/* Request code */
144  u_char id;			/* Identification */
145  u_short length;		/* Length of packet */
146};
147
148#define	CODE_CONFIGREQ	1
149#define	CODE_CONFIGACK	2
150#define	CODE_CONFIGNAK	3
151#define	CODE_CONFIGREJ	4
152#define	CODE_TERMREQ	5
153#define	CODE_TERMACK	6
154#define	CODE_CODEREJ	7
155#define	CODE_PROTOREJ	8
156#define	CODE_ECHOREQ	9	/* Used in LCP */
157#define	CODE_ECHOREP	10	/* Used in LCP */
158#define	CODE_DISCREQ	11
159#define	CODE_IDENT	12	/* Used in LCP Extension */
160#define	CODE_TIMEREM	13	/* Used in LCP Extension */
161#define	CODE_RESETREQ	14	/* Used in CCP */
162#define	CODE_RESETACK	15	/* Used in CCP */
163
164struct fsm_opt_hdr {
165  u_char id;
166  u_char len;
167};
168
169#define MAX_FSM_OPT_LEN 52
170struct fsm_opt {
171  struct fsm_opt_hdr hdr;
172  u_char data[MAX_FSM_OPT_LEN-2];
173};
174
175#define INC_FSM_OPT(ty, length, o)                      \
176  do {                                                  \
177    (o)->hdr.id = (ty);                                 \
178    (o)->hdr.len = (length);                            \
179    (o) = (struct fsm_opt *)((u_char *)(o) + (length)); \
180  } while (0)
181
182
183extern void fsm_Init(struct fsm *, const char *, u_short, int, int, int,
184                     struct bundle *, struct link *, const  struct fsm_parent *,
185                     struct fsm_callbacks *, const char * const [3]);
186extern void fsm_Output(struct fsm *, u_int, u_int, u_char *, unsigned, int);
187extern void fsm_Open(struct fsm *);
188extern void fsm_Up(struct fsm *);
189extern void fsm_Down(struct fsm *);
190extern void fsm_Input(struct fsm *, struct mbuf *);
191extern void fsm_Close(struct fsm *);
192extern int fsm_NullRecvResetReq(struct fsm *);
193extern void fsm_NullRecvResetAck(struct fsm *, u_char);
194extern void fsm_Reopen(struct fsm *);
195extern void fsm2initial(struct fsm *);
196extern const char *State2Nam(u_int);
197extern struct fsm_opt *fsm_readopt(u_char **);
198extern void fsm_rej(struct fsm_decode *, const struct fsm_opt *);
199extern void fsm_ack(struct fsm_decode *, const struct fsm_opt *);
200extern void fsm_nak(struct fsm_decode *, const struct fsm_opt *);
201extern void fsm_opt_normalise(struct fsm_decode *);
202