1/*
2 * fsm.h - {Link, IP} Control Protocol Finite State Machine definitions.
3 *
4 * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in
15 *    the documentation and/or other materials provided with the
16 *    distribution.
17 *
18 * 3. The name "Carnegie Mellon University" must not be used to
19 *    endorse or promote products derived from this software without
20 *    prior written permission. For permission or any legal
21 *    details, please contact
22 *      Office of Technology Transfer
23 *      Carnegie Mellon University
24 *      5000 Forbes Avenue
25 *      Pittsburgh, PA  15213-3890
26 *      (412) 268-4387, fax: (412) 268-7395
27 *      tech-transfer@andrew.cmu.edu
28 *
29 * 4. Redistributions of any form whatsoever must retain the following
30 *    acknowledgment:
31 *    "This product includes software developed by Computing Services
32 *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
33 *
34 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
35 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
36 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
37 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
38 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
39 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
40 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
41 *
42 * $Id: fsm.h,v 1.10 2004/11/13 02:28:15 paulus Exp $
43 */
44
45#include "netif/ppp/ppp_opts.h"
46#if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
47
48#ifndef FSM_H
49#define	FSM_H
50
51#include "ppp.h"
52
53/*
54 * Packet header = Code, id, length.
55 */
56#define HEADERLEN	4
57
58
59/*
60 *  CP (LCP, IPCP, etc.) codes.
61 */
62#define CONFREQ		1	/* Configuration Request */
63#define CONFACK		2	/* Configuration Ack */
64#define CONFNAK		3	/* Configuration Nak */
65#define CONFREJ		4	/* Configuration Reject */
66#define TERMREQ		5	/* Termination Request */
67#define TERMACK		6	/* Termination Ack */
68#define CODEREJ		7	/* Code Reject */
69
70
71/*
72 * Each FSM is described by an fsm structure and fsm callbacks.
73 */
74typedef struct fsm {
75    ppp_pcb *pcb;		/* PPP Interface */
76    const struct fsm_callbacks *callbacks;	/* Callback routines */
77    const char *term_reason;	/* Reason for closing protocol */
78    u8_t seen_ack;		/* Have received valid Ack/Nak/Rej to Req */
79				  /* -- This is our only flag, we might use u_int :1 if we have more flags */
80    u16_t protocol;		/* Data Link Layer Protocol field value */
81    u8_t state;			/* State */
82    u8_t flags;			/* Contains option bits */
83    u8_t id;			/* Current id */
84    u8_t reqid;			/* Current request id */
85    u8_t retransmits;		/* Number of retransmissions left */
86    u8_t nakloops;		/* Number of nak loops since last ack */
87    u8_t rnakloops;		/* Number of naks received */
88    u8_t maxnakloops;		/* Maximum number of nak loops tolerated
89				   (necessary because IPCP require a custom large max nak loops value) */
90    u8_t term_reason_len;	/* Length of term_reason */
91} fsm;
92
93
94typedef struct fsm_callbacks {
95    void (*resetci)		/* Reset our Configuration Information */
96		(fsm *);
97    int  (*cilen)		/* Length of our Configuration Information */
98		(fsm *);
99    void (*addci) 		/* Add our Configuration Information */
100		(fsm *, u_char *, int *);
101    int  (*ackci)		/* ACK our Configuration Information */
102		(fsm *, u_char *, int);
103    int  (*nakci)		/* NAK our Configuration Information */
104		(fsm *, u_char *, int, int);
105    int  (*rejci)		/* Reject our Configuration Information */
106		(fsm *, u_char *, int);
107    int  (*reqci)		/* Request peer's Configuration Information */
108		(fsm *, u_char *, int *, int);
109    void (*up)			/* Called when fsm reaches PPP_FSM_OPENED state */
110		(fsm *);
111    void (*down)		/* Called when fsm leaves PPP_FSM_OPENED state */
112		(fsm *);
113    void (*starting)		/* Called when we want the lower layer */
114		(fsm *);
115    void (*finished)		/* Called when we don't want the lower layer */
116		(fsm *);
117    void (*protreject)		/* Called when Protocol-Reject received */
118		(int);
119    void (*retransmit)		/* Retransmission is necessary */
120		(fsm *);
121    int  (*extcode)		/* Called when unknown code received */
122		(fsm *, int, int, u_char *, int);
123    const char *proto_name;	/* String name for protocol (for messages) */
124} fsm_callbacks;
125
126
127/*
128 * Link states.
129 */
130#define PPP_FSM_INITIAL		0	/* Down, hasn't been opened */
131#define PPP_FSM_STARTING	1	/* Down, been opened */
132#define PPP_FSM_CLOSED		2	/* Up, hasn't been opened */
133#define PPP_FSM_STOPPED		3	/* Open, waiting for down event */
134#define PPP_FSM_CLOSING		4	/* Terminating the connection, not open */
135#define PPP_FSM_STOPPING	5	/* Terminating, but open */
136#define PPP_FSM_REQSENT		6	/* We've sent a Config Request */
137#define PPP_FSM_ACKRCVD		7	/* We've received a Config Ack */
138#define PPP_FSM_ACKSENT		8	/* We've sent a Config Ack */
139#define PPP_FSM_OPENED		9	/* Connection available */
140
141
142/*
143 * Flags - indicate options controlling FSM operation
144 */
145#define OPT_PASSIVE	1	/* Don't die if we don't get a response */
146#define OPT_RESTART	2	/* Treat 2nd OPEN as DOWN, UP */
147#define OPT_SILENT	4	/* Wait for peer to speak first */
148
149
150/*
151 * Timeouts.
152 */
153#if 0 /* moved to ppp_opts.h */
154#define DEFTIMEOUT	3	/* Timeout time in seconds */
155#define DEFMAXTERMREQS	2	/* Maximum Terminate-Request transmissions */
156#define DEFMAXCONFREQS	10	/* Maximum Configure-Request transmissions */
157#define DEFMAXNAKLOOPS	5	/* Maximum number of nak loops */
158#endif /* moved to ppp_opts.h */
159
160
161/*
162 * Prototypes
163 */
164void fsm_init(fsm *f);
165void fsm_lowerup(fsm *f);
166void fsm_lowerdown(fsm *f);
167void fsm_open(fsm *f);
168void fsm_close(fsm *f, const char *reason);
169void fsm_input(fsm *f, u_char *inpacket, int l);
170void fsm_protreject(fsm *f);
171void fsm_sdata(fsm *f, u_char code, u_char id, const u_char *data, int datalen);
172
173
174#endif /* FSM_H */
175#endif /* PPP_SUPPORT */
176