1/* 2 * fsm.h - {Link, IP} Control Protocol Finite State Machine definitions. 3 * 4 * Copyright (c) 1989 Carnegie Mellon University. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms are permitted 8 * provided that the above copyright notice and this paragraph are 9 * duplicated in all such forms and that any documentation, 10 * advertising materials, and other materials related to such 11 * distribution and use acknowledge that the software was developed 12 * by Carnegie Mellon University. The name of the 13 * University may not be used to endorse or promote products derived 14 * from this software without specific prior written permission. 15 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 17 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 18 * 19 * $Id$ 20 */ 21 22/* 23 * Packet header = Code, id, length. 24 */ 25#define HEADERLEN 4 26 27 28/* 29 * CP (LCP, IPCP, etc.) codes. 30 */ 31#define CONFREQ 1 /* Configuration Request */ 32#define CONFACK 2 /* Configuration Ack */ 33#define CONFNAK 3 /* Configuration Nak */ 34#define CONFREJ 4 /* Configuration Reject */ 35#define TERMREQ 5 /* Termination Request */ 36#define TERMACK 6 /* Termination Ack */ 37#define CODEREJ 7 /* Code Reject */ 38 39 40/* 41 * Each FSM is described by an fsm structure and fsm callbacks. 42 */ 43typedef struct fsm { 44 int unit; /* Interface unit number */ 45 int protocol; /* Data Link Layer Protocol field value */ 46 int state; /* State */ 47 int flags; /* Contains option bits */ 48 u_char id; /* Current id */ 49 u_char reqid; /* Current request id */ 50 u_char seen_ack; /* Have received valid Ack/Nak/Rej to Req */ 51 int timeouttime; /* Timeout time in milliseconds */ 52 int maxconfreqtransmits; /* Maximum Configure-Request transmissions */ 53 int retransmits; /* Number of retransmissions left */ 54 int maxtermtransmits; /* Maximum Terminate-Request transmissions */ 55 int nakloops; /* Number of nak loops since last ack */ 56 int maxnakloops; /* Maximum number of nak loops tolerated */ 57 struct fsm_callbacks *callbacks; /* Callback routines */ 58 char *term_reason; /* Reason for closing protocol */ 59 int term_reason_len; /* Length of term_reason */ 60} fsm; 61 62 63typedef struct fsm_callbacks { 64 void (*resetci) /* Reset our Configuration Information */ 65 __P((fsm *)); 66 int (*cilen) /* Length of our Configuration Information */ 67 __P((fsm *)); 68 void (*addci) /* Add our Configuration Information */ 69 __P((fsm *, u_char *, int *)); 70 int (*ackci) /* ACK our Configuration Information */ 71 __P((fsm *, u_char *, int)); 72 int (*nakci) /* NAK our Configuration Information */ 73 __P((fsm *, u_char *, int)); 74 int (*rejci) /* Reject our Configuration Information */ 75 __P((fsm *, u_char *, int)); 76 int (*reqci) /* Request peer's Configuration Information */ 77 __P((fsm *, u_char *, int *, int)); 78 void (*up) /* Called when fsm reaches OPENED state */ 79 __P((fsm *)); 80 void (*down) /* Called when fsm leaves OPENED state */ 81 __P((fsm *)); 82 void (*starting) /* Called when we want the lower layer */ 83 __P((fsm *)); 84 void (*finished) /* Called when we don't want the lower layer */ 85 __P((fsm *)); 86 void (*protreject) /* Called when Protocol-Reject received */ 87 __P((int)); 88 void (*retransmit) /* Retransmission is necessary */ 89 __P((fsm *)); 90 int (*extcode) /* Called when unknown code received */ 91 __P((fsm *, int, int, u_char *, int)); 92 char *proto_name; /* String name for protocol (for messages) */ 93} fsm_callbacks; 94 95 96/* 97 * Link states. 98 */ 99#define INITIAL 0 /* Down, hasn't been opened */ 100#define STARTING 1 /* Down, been opened */ 101#define CLOSED 2 /* Up, hasn't been opened */ 102#define STOPPED 3 /* Open, waiting for down event */ 103#define CLOSING 4 /* Terminating the connection, not open */ 104#define STOPPING 5 /* Terminating, but open */ 105#define REQSENT 6 /* We've sent a Config Request */ 106#define ACKRCVD 7 /* We've received a Config Ack */ 107#define ACKSENT 8 /* We've sent a Config Ack */ 108#define OPENED 9 /* Connection available */ 109 110 111/* 112 * Flags - indicate options controlling FSM operation 113 */ 114#define OPT_PASSIVE 1 /* Don't die if we don't get a response */ 115#define OPT_RESTART 2 /* Treat 2nd OPEN as DOWN, UP */ 116#define OPT_SILENT 4 /* Wait for peer to speak first */ 117 118 119/* 120 * Timeouts. 121 */ 122#define DEFTIMEOUT 3 /* Timeout time in seconds */ 123#define DEFMAXTERMREQS 2 /* Maximum Terminate-Request transmissions */ 124#define DEFMAXCONFREQS 10 /* Maximum Configure-Request transmissions */ 125#define DEFMAXNAKLOOPS 5 /* Maximum number of nak loops */ 126 127 128/* 129 * Prototypes 130 */ 131void fsm_init __P((fsm *)); 132void fsm_lowerup __P((fsm *)); 133void fsm_lowerdown __P((fsm *)); 134void fsm_open __P((fsm *)); 135void fsm_close __P((fsm *, char *)); 136void fsm_input __P((fsm *, u_char *, int)); 137void fsm_protreject __P((fsm *)); 138void fsm_sdata __P((fsm *, int, int, u_char *, int)); 139 140 141/* 142 * Variables 143 */ 144extern int peer_mru[]; /* currently negotiated peer MRU (per unit) */ 145