1 /* $OpenBSD: fsm.h,v 1.2 1996/03/25 15:55:39 niklas Exp $ */ 2 3 /* 4 * fsm.h - {Link, IP} Control Protocol Finite State Machine definitions. 5 * 6 * Copyright (c) 1989 Carnegie Mellon University. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms are permitted 10 * provided that the above copyright notice and this paragraph are 11 * duplicated in all such forms and that any documentation, 12 * advertising materials, and other materials related to such 13 * distribution and use acknowledge that the software was developed 14 * by Carnegie Mellon University. The name of the 15 * University may not be used to endorse or promote products derived 16 * from this software without specific prior written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 19 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 */ 21 22 /* 23 * Packet header = Code, id, length. 24 */ 25 #define HEADERLEN (sizeof (u_char) + sizeof (u_char) + sizeof (u_short)) 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 a fsm_callbacks and a fsm structure. 42 */ 43 typedef struct fsm_callbacks { 44 void (*resetci)(); /* Reset our Configuration Information */ 45 int (*cilen)(); /* Length of our Configuration Information */ 46 void (*addci)(); /* Add our Configuration Information */ 47 int (*ackci)(); /* ACK our Configuration Information */ 48 int (*nakci)(); /* NAK our Configuration Information */ 49 int (*rejci)(); /* Reject our Configuration Information */ 50 int (*reqci)(); /* Request peer's Configuration Information */ 51 void (*up)(); /* Called when fsm reaches OPENED state */ 52 void (*down)(); /* Called when fsm leaves OPENED state */ 53 void (*starting)(); /* Called when we want the lower layer */ 54 void (*finished)(); /* Called when we don't want the lower layer */ 55 void (*protreject)(); /* Called when Protocol-Reject received */ 56 void (*retransmit)(); /* Retransmission is necessary */ 57 int (*extcode)(); /* Called when unknown code received */ 58 char *proto_name; /* String name for protocol (for messages) */ 59 } fsm_callbacks; 60 61 62 typedef struct fsm { 63 int unit; /* Interface unit number */ 64 int protocol; /* Data Link Layer Protocol field value */ 65 int state; /* State */ 66 int flags; /* Contains option bits */ 67 u_char id; /* Current id */ 68 u_char reqid; /* Current request id */ 69 u_char seen_ack; /* Have received valid Ack/Nak/Rej to Req */ 70 int timeouttime; /* Timeout time in milliseconds */ 71 int maxconfreqtransmits; /* Maximum Configure-Request transmissions */ 72 int retransmits; /* Number of retransmissions left */ 73 int maxtermtransmits; /* Maximum Terminate-Request transmissions */ 74 int nakloops; /* Number of nak loops since last ack */ 75 int maxnakloops; /* Maximum number of nak loops tolerated */ 76 fsm_callbacks *callbacks; /* Callback routines */ 77 char *term_reason; /* Reason for closing protocol */ 78 int term_reason_len; /* Length of term_reason */ 79 } fsm; 80 81 82 /* 83 * Link states. 84 */ 85 #define INITIAL 0 /* Down, hasn't been opened */ 86 #define STARTING 1 /* Down, been opened */ 87 #define CLOSED 2 /* Up, hasn't been opened */ 88 #define STOPPED 3 /* Open, waiting for down event */ 89 #define CLOSING 4 /* Terminating the connection, not open */ 90 #define STOPPING 5 /* Terminating, but open */ 91 #define REQSENT 6 /* We've sent a Config Request */ 92 #define ACKRCVD 7 /* We've received a Config Ack */ 93 #define ACKSENT 8 /* We've sent a Config Ack */ 94 #define OPENED 9 /* Connection available */ 95 96 97 /* 98 * Flags - indicate options controlling FSM operation 99 */ 100 #define OPT_PASSIVE 1 /* Don't die if we don't get a response */ 101 #define OPT_RESTART 2 /* Treat 2nd OPEN as DOWN, UP */ 102 #define OPT_SILENT 4 /* Wait for peer to speak first */ 103 104 105 /* 106 * Timeouts. 107 */ 108 #define DEFTIMEOUT 3 /* Timeout time in seconds */ 109 #define DEFMAXTERMREQS 2 /* Maximum Terminate-Request transmissions */ 110 #define DEFMAXCONFREQS 10 /* Maximum Configure-Request transmissions */ 111 #define DEFMAXNAKLOOPS 5 /* Maximum number of nak loops */ 112 113 114 /* 115 * Prototypes 116 */ 117 void fsm_init __P((fsm *)); 118 void fsm_lowerup __P((fsm *)); 119 void fsm_lowerdown __P((fsm *)); 120 void fsm_open __P((fsm *)); 121 void fsm_close __P((fsm *, char *)); 122 void fsm_input __P((fsm *, u_char *, int)); 123 void fsm_protreject __P((fsm *)); 124 void fsm_sdata __P((fsm *, int, int, u_char *, int)); 125 126 127 /* 128 * Variables 129 */ 130 extern int peer_mru[]; /* currently negotiated peer MRU (per unit) */ 131