hdlc.c revision 28679
1/* 2 * PPP High Level Link Control (HDLC) Module 3 * 4 * Written by Toshiharu OHNO (tony-o@iij.ad.jp) 5 * 6 * Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by the Internet Initiative Japan, Inc. The name of the 14 * IIJ may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * $Id: hdlc.c,v 1.16 1997/06/09 03:27:22 brian Exp $ 21 * 22 * TODO: 23 */ 24#include "fsm.h" 25#include "hdlc.h" 26#include "lcpproto.h" 27#include "lcp.h" 28#include "lqr.h" 29#include "loadalias.h" 30#include "vars.h" 31#include "pred.h" 32#include "modem.h" 33#include "ccp.h" 34 35struct hdlcstat { 36 int badfcs; 37 int badaddr; 38 int badcommand; 39 int unknownproto; 40} HdlcStat; 41 42static int ifOutPackets, ifOutOctets, ifOutLQRs; 43static int ifInPackets, ifInOctets; 44 45struct protostat { 46 u_short number; 47 char *name; 48 u_long in_count; 49 u_long out_count; 50} ProtocolStat[] = { 51 52 { 53 PROTO_IP, "IP" 54 }, 55 { 56 PROTO_VJUNCOMP, "VJ_UNCOMP" 57 }, 58 { 59 PROTO_VJCOMP, "VJ_COMP" 60 }, 61 { 62 PROTO_COMPD, "COMPD" 63 }, 64 { 65 PROTO_LCP, "LCP" 66 }, 67 { 68 PROTO_IPCP, "IPCP" 69 }, 70 { 71 PROTO_CCP, "CCP" 72 }, 73 { 74 PROTO_PAP, "PAP" 75 }, 76 { 77 PROTO_LQR, "LQR" 78 }, 79 { 80 PROTO_CHAP, "CHAP" 81 }, 82 { 83 0, "Others" 84 }, 85}; 86 87static u_short const fcstab[256] = { 88 /* 00 */ 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, 89 /* 08 */ 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, 90 /* 10 */ 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, 91 /* 18 */ 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, 92 /* 20 */ 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, 93 /* 28 */ 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, 94 /* 30 */ 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, 95 /* 38 */ 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, 96 /* 40 */ 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, 97 /* 48 */ 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, 98 /* 50 */ 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, 99 /* 58 */ 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, 100 /* 60 */ 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, 101 /* 68 */ 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, 102 /* 70 */ 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, 103 /* 78 */ 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, 104 /* 80 */ 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, 105 /* 88 */ 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, 106 /* 90 */ 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, 107 /* 98 */ 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, 108 /* a0 */ 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, 109 /* a8 */ 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, 110 /* b0 */ 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, 111 /* b8 */ 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, 112 /* c0 */ 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, 113 /* c8 */ 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, 114 /* d0 */ 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, 115 /* d8 */ 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, 116 /* e0 */ 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, 117 /* e8 */ 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, 118 /* f0 */ 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, 119 /* f8 */ 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 120}; 121 122u_char EscMap[33]; 123 124void 125HdlcInit() 126{ 127 ifInOctets = ifOutOctets = 0; 128 ifInPackets = ifOutPackets = 0; 129 ifOutLQRs = 0; 130} 131 132/* 133 * HDLC FCS computation. Read RFC 1171 Appendix B and CCITT X.25 section 134 * 2.27 for further details. 135 */ 136inline u_short 137HdlcFcs(u_short fcs, u_char * cp, int len) 138{ 139 while (len--) 140 fcs = (fcs >> 8) ^ fcstab[(fcs ^ *cp++) & 0xff]; 141 return (fcs); 142} 143 144void 145HdlcOutput(int pri, u_short proto, struct mbuf * bp) 146{ 147 struct mbuf *mhp, *mfcs; 148 struct protostat *statp; 149 struct lqrdata *lqr; 150 u_char *cp; 151 u_short fcs; 152 153 if ((proto & 0xfff1) == 0x21) { /* Network Layer protocol */ 154 if (CcpFsm.state == ST_OPENED) { 155 Pred1Output(pri, proto, bp); 156 return; 157 } 158 } 159 if (DEV_IS_SYNC) 160 mfcs = NULLBUFF; 161 else 162 mfcs = mballoc(2, MB_HDLCOUT); 163 mhp = mballoc(4, MB_HDLCOUT); 164 mhp->cnt = 0; 165 cp = MBUF_CTOP(mhp); 166 if (proto == PROTO_LCP || LcpInfo.his_acfcomp == 0) { 167 *cp++ = HDLC_ADDR; 168 *cp++ = HDLC_UI; 169 mhp->cnt += 2; 170 } 171 172 /* 173 * If possible, compress protocol field. 174 */ 175 if (LcpInfo.his_protocomp && (proto & 0xff00) == 0) { 176 *cp++ = proto; 177 mhp->cnt++; 178 } else { 179 *cp++ = proto >> 8; 180 *cp = proto & 0377; 181 mhp->cnt += 2; 182 } 183 mhp->next = bp; 184 bp->next = mfcs; 185 186 lqr = &MyLqrData; 187 lqr->PeerOutPackets = ifOutPackets++; 188 ifOutOctets += plength(mhp) + 1; 189 lqr->PeerOutOctets = ifOutOctets; 190 191 if (proto == PROTO_LQR) { 192 lqr->MagicNumber = LcpInfo.want_magic; 193 lqr->LastOutLQRs = HisLqrData.PeerOutLQRs; 194 lqr->LastOutPackets = HisLqrData.PeerOutPackets; 195 lqr->LastOutOctets = HisLqrData.PeerOutOctets; 196 lqr->PeerInLQRs = HisLqrSave.SaveInLQRs; 197 lqr->PeerInPackets = HisLqrSave.SaveInPackets; 198 lqr->PeerInDiscards = HisLqrSave.SaveInDiscards; 199 lqr->PeerInErrors = HisLqrSave.SaveInErrors; 200 lqr->PeerInOctets = HisLqrSave.SaveInOctets; 201 lqr->PeerOutLQRs = ++ifOutLQRs; 202 LqrDump("LqrOutput", lqr); 203 LqrChangeOrder(lqr, (struct lqrdata *) (MBUF_CTOP(bp))); 204 } 205 if (!DEV_IS_SYNC) { 206 fcs = HdlcFcs(INITFCS, MBUF_CTOP(mhp), mhp->cnt); 207 fcs = HdlcFcs(fcs, MBUF_CTOP(bp), bp->cnt); 208 fcs = ~fcs; 209 cp = MBUF_CTOP(mfcs); 210 *cp++ = fcs & 0377; /* Low byte first!! */ 211 *cp++ = fcs >> 8; 212 } 213 LogDumpBp(LogHDLC, "HdlcOutput", mhp); 214 for (statp = ProtocolStat; statp->number; statp++) 215 if (statp->number == proto) 216 break; 217 statp->out_count++; 218 if (DEV_IS_SYNC) 219 ModemOutput(pri, mhp); 220 else 221 AsyncOutput(pri, mhp, proto); 222} 223 224void 225DecodePacket(u_short proto, struct mbuf * bp) 226{ 227 u_char *cp; 228 229 LogPrintf(LogDEBUG, "DecodePacket: proto = %04x\n", proto); 230 231 switch (proto) { 232 case PROTO_LCP: 233 LcpInput(bp); 234 break; 235 case PROTO_PAP: 236 PapInput(bp); 237 break; 238 case PROTO_LQR: 239 HisLqrSave.SaveInLQRs++; 240 LqrInput(bp); 241 break; 242 case PROTO_CHAP: 243 ChapInput(bp); 244 break; 245 case PROTO_VJUNCOMP: 246 case PROTO_VJCOMP: 247 bp = VjCompInput(bp, proto); 248 if (bp == NULLBUFF) { 249 break; 250 } 251 /* fall down */ 252 case PROTO_IP: 253 IpInput(bp); 254 break; 255 case PROTO_IPCP: 256 IpcpInput(bp); 257 break; 258 case PROTO_CCP: 259 CcpInput(bp); 260 break; 261 case PROTO_COMPD: 262 Pred1Input(bp); 263 break; 264 default: 265 LogPrintf(LogPHASE, "Unknown protocol 0x%04x\n", proto); 266 bp->offset -= 2; 267 bp->cnt += 2; 268 cp = MBUF_CTOP(bp); 269 LcpSendProtoRej(cp, bp->cnt); 270 HisLqrSave.SaveInDiscards++; 271 HdlcStat.unknownproto++; 272 pfree(bp); 273 break; 274 } 275} 276 277int 278ReportProtStatus() 279{ 280 struct protostat *statp; 281 int cnt; 282 283 statp = ProtocolStat; 284 statp--; 285 cnt = 0; 286 fprintf(VarTerm, " Protocol in out Protocol in out\n"); 287 do { 288 statp++; 289 fprintf(VarTerm, " %-9s: %8lu, %8lu", 290 statp->name, statp->in_count, statp->out_count); 291 if (++cnt == 2) { 292 fprintf(VarTerm, "\n"); 293 cnt = 0; 294 } 295 } while (statp->number); 296 if (cnt) 297 fprintf(VarTerm, "\n"); 298 return (1); 299} 300 301int 302ReportHdlcStatus() 303{ 304 struct hdlcstat *hp = &HdlcStat; 305 306 if (VarTerm) { 307 fprintf(VarTerm, "HDLC level errors\n\n"); 308 fprintf(VarTerm, "FCS: %u ADDR: %u COMMAND: %u PROTO: %u\n", 309 hp->badfcs, hp->badaddr, hp->badcommand, hp->unknownproto); 310 } 311 return 0; 312} 313 314static struct hdlcstat laststat; 315 316void 317HdlcErrorCheck() 318{ 319 struct hdlcstat *hp = &HdlcStat; 320 struct hdlcstat *op = &laststat; 321 322 if (bcmp(hp, op, sizeof(laststat))) { 323 LogPrintf(LogPHASE, "HDLC errors -> FCS: %u ADDR: %u COMD: %u PROTO: %u\n", 324 hp->badfcs - op->badfcs, hp->badaddr - op->badaddr, 325 hp->badcommand - op->badcommand, hp->unknownproto - op->unknownproto); 326 } 327 laststat = HdlcStat; 328} 329 330void 331HdlcInput(struct mbuf * bp) 332{ 333 u_short fcs, proto; 334 u_char *cp, addr, ctrl; 335 struct protostat *statp; 336 337 LogDumpBp(LogHDLC, "HdlcInput:", bp); 338 if (DEV_IS_SYNC) 339 fcs = GOODFCS; 340 else 341 fcs = HdlcFcs(INITFCS, MBUF_CTOP(bp), bp->cnt); 342 HisLqrSave.SaveInOctets += bp->cnt + 1; 343 344 LogPrintf(LogDEBUG, "HdlcInput: fcs = %04x (%s)\n", 345 fcs, (fcs == GOODFCS) ? "good" : "bad"); 346 if (fcs != GOODFCS) { 347 HisLqrSave.SaveInErrors++; 348 LogPrintf(LogDEBUG, "HdlcInput: Bad FCS\n"); 349 HdlcStat.badfcs++; 350 pfree(bp); 351 return; 352 } 353 if (!DEV_IS_SYNC) 354 bp->cnt -= 2; /* discard FCS part */ 355 356 if (bp->cnt < 2) { /* XXX: raise this bar ? */ 357 pfree(bp); 358 return; 359 } 360 cp = MBUF_CTOP(bp); 361 362 ifInPackets++; 363 ifInOctets += bp->cnt; 364 365 if (!LcpInfo.want_acfcomp) { 366 367 /* 368 * We expect that packet is not compressed. 369 */ 370 addr = *cp++; 371 if (addr != HDLC_ADDR) { 372 HisLqrSave.SaveInErrors++; 373 HdlcStat.badaddr++; 374 LogPrintf(LogDEBUG, "HdlcInput: addr %02x\n", *cp); 375 pfree(bp); 376 return; 377 } 378 ctrl = *cp++; 379 if (ctrl != HDLC_UI) { 380 HisLqrSave.SaveInErrors++; 381 HdlcStat.badcommand++; 382 LogPrintf(LogDEBUG, "HdlcInput: %02x\n", *cp); 383 pfree(bp); 384 return; 385 } 386 bp->offset += 2; 387 bp->cnt -= 2; 388 } else if (cp[0] == HDLC_ADDR && cp[1] == HDLC_UI) { 389 390 /* 391 * We can receive compressed packet, but peer still send uncompressed 392 * packet to me. 393 */ 394 cp += 2; 395 bp->offset += 2; 396 bp->cnt -= 2; 397 } 398 if (LcpInfo.want_protocomp) { 399 proto = 0; 400 cp--; 401 do { 402 cp++; 403 bp->offset++; 404 bp->cnt--; 405 proto = proto << 8; 406 proto += *cp; 407 } while (!(proto & 1)); 408 } else { 409 proto = *cp++ << 8; 410 proto |= *cp++; 411 bp->offset += 2; 412 bp->cnt -= 2; 413 } 414 415 for (statp = ProtocolStat; statp->number; statp++) 416 if (statp->number == proto) 417 break; 418 statp->in_count++; 419 HisLqrSave.SaveInPackets++; 420 421 DecodePacket(proto, bp); 422} 423