1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org> 5 * based on work by Toshiharu OHNO <tony-o@iij.ad.jp> 6 * Internet Initiative Japan, Inc (IIJ) 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 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 61 struct fsm; 62 63 struct 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 69 struct 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 75 struct 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 90 struct 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 98 struct link; 99 struct bundle; 100 101 struct 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 }; 141 142 struct 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 */ 163 164 struct fsm_opt_hdr { 165 u_char id; 166 u_char len; 167 } __packed; 168 169 #define MAX_FSM_OPT_LEN 52 170 struct 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) 181 182 183 extern 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]); 186 extern void fsm_Output(struct fsm *, u_int, u_int, u_char *, unsigned, int); 187 extern void fsm_Open(struct fsm *); 188 extern void fsm_Up(struct fsm *); 189 extern void fsm_Down(struct fsm *); 190 extern void fsm_Input(struct fsm *, struct mbuf *); 191 extern void fsm_Close(struct fsm *); 192 extern int fsm_NullRecvResetReq(struct fsm *); 193 extern void fsm_NullRecvResetAck(struct fsm *, u_char); 194 extern void fsm_Reopen(struct fsm *); 195 extern void fsm2initial(struct fsm *); 196 extern const char *State2Nam(u_int); 197 extern struct fsm_opt *fsm_readopt(u_char **); 198 extern void fsm_rej(struct fsm_decode *, const struct fsm_opt *); 199 extern void fsm_ack(struct fsm_decode *, const struct fsm_opt *); 200 extern void fsm_nak(struct fsm_decode *, const struct fsm_opt *); 201 extern void fsm_opt_normalise(struct fsm_decode *); 202