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 1.18 1997/09/10 21:33:32 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 35 struct hdlcstat { 36 int badfcs; 37 int badaddr; 38 int badcommand; 39 int unknownproto; 40 } HdlcStat; 41 42 static int ifOutPackets, ifOutOctets, ifOutLQRs; 43 static int ifInPackets, ifInOctets; 44 45 struct 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 87 static 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 }; 121 122 u_char EscMap[33]; 123 124 void 125 HdlcInit() 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 */ 136 inline u_short 137 HdlcFcs(u_short fcs, u_char * cp, int len) 138 { 139 while (len--) 140 fcs = (fcs >> 8) ^ fcstab[(fcs ^ *cp++) & 0xff]; 141 return (fcs); 142 } 143 144 void 145 HdlcOutput(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 if (CcpInfo.want_proto == TY_PRED1) { 156 Pred1Output(pri, proto, bp); 157 return; 158 } 159 } 160 } 161 if (DEV_IS_SYNC) 162 mfcs = NULLBUFF; 163 else 164 mfcs = mballoc(2, MB_HDLCOUT); 165 mhp = mballoc(4, MB_HDLCOUT); 166 mhp->cnt = 0; 167 cp = MBUF_CTOP(mhp); 168 if (proto == PROTO_LCP || LcpInfo.his_acfcomp == 0) { 169 *cp++ = HDLC_ADDR; 170 *cp++ = HDLC_UI; 171 mhp->cnt += 2; 172 } 173 174 /* 175 * If possible, compress protocol field. 176 */ 177 if (LcpInfo.his_protocomp && (proto & 0xff00) == 0) { 178 *cp++ = proto; 179 mhp->cnt++; 180 } else { 181 *cp++ = proto >> 8; 182 *cp = proto & 0377; 183 mhp->cnt += 2; 184 } 185 mhp->next = bp; 186 bp->next = mfcs; 187 188 lqr = &MyLqrData; 189 lqr->PeerOutPackets = ifOutPackets++; 190 ifOutOctets += plength(mhp) + 1; 191 lqr->PeerOutOctets = ifOutOctets; 192 193 if (proto == PROTO_LQR) { 194 lqr->MagicNumber = LcpInfo.want_magic; 195 lqr->LastOutLQRs = HisLqrData.PeerOutLQRs; 196 lqr->LastOutPackets = HisLqrData.PeerOutPackets; 197 lqr->LastOutOctets = HisLqrData.PeerOutOctets; 198 lqr->PeerInLQRs = HisLqrSave.SaveInLQRs; 199 lqr->PeerInPackets = HisLqrSave.SaveInPackets; 200 lqr->PeerInDiscards = HisLqrSave.SaveInDiscards; 201 lqr->PeerInErrors = HisLqrSave.SaveInErrors; 202 lqr->PeerInOctets = HisLqrSave.SaveInOctets; 203 lqr->PeerOutLQRs = ++ifOutLQRs; 204 LqrDump("LqrOutput", lqr); 205 LqrChangeOrder(lqr, (struct lqrdata *) (MBUF_CTOP(bp))); 206 } 207 if (!DEV_IS_SYNC) { 208 fcs = HdlcFcs(INITFCS, MBUF_CTOP(mhp), mhp->cnt); 209 fcs = HdlcFcs(fcs, MBUF_CTOP(bp), bp->cnt); 210 fcs = ~fcs; 211 cp = MBUF_CTOP(mfcs); 212 *cp++ = fcs & 0377; /* Low byte first!! */ 213 *cp++ = fcs >> 8; 214 } 215 LogDumpBp(LogHDLC, "HdlcOutput", mhp); 216 for (statp = ProtocolStat; statp->number; statp++) 217 if (statp->number == proto) 218 break; 219 statp->out_count++; 220 if (DEV_IS_SYNC) 221 ModemOutput(pri, mhp); 222 else 223 AsyncOutput(pri, mhp, proto); 224 } 225 226 void 227 DecodePacket(u_short proto, struct mbuf * bp) 228 { 229 u_char *cp; 230 231 LogPrintf(LogDEBUG, "DecodePacket: proto = %04x\n", proto); 232 233 switch (proto) { 234 case PROTO_LCP: 235 LcpInput(bp); 236 break; 237 case PROTO_PAP: 238 PapInput(bp); 239 break; 240 case PROTO_LQR: 241 HisLqrSave.SaveInLQRs++; 242 LqrInput(bp); 243 break; 244 case PROTO_CHAP: 245 ChapInput(bp); 246 break; 247 case PROTO_VJUNCOMP: 248 case PROTO_VJCOMP: 249 bp = VjCompInput(bp, proto); 250 if (bp == NULLBUFF) { 251 break; 252 } 253 /* fall down */ 254 case PROTO_IP: 255 IpInput(bp); 256 break; 257 case PROTO_IPCP: 258 IpcpInput(bp); 259 break; 260 case PROTO_CCP: 261 CcpInput(bp); 262 break; 263 case PROTO_COMPD: 264 Pred1Input(bp); 265 break; 266 default: 267 LogPrintf(LogPHASE, "Unknown protocol 0x%04x\n", proto); 268 bp->offset -= 2; 269 bp->cnt += 2; 270 cp = MBUF_CTOP(bp); 271 LcpSendProtoRej(cp, bp->cnt); 272 HisLqrSave.SaveInDiscards++; 273 HdlcStat.unknownproto++; 274 pfree(bp); 275 break; 276 } 277 } 278 279 int 280 ReportProtStatus() 281 { 282 struct protostat *statp; 283 int cnt; 284 285 statp = ProtocolStat; 286 statp--; 287 cnt = 0; 288 fprintf(VarTerm, " Protocol in out Protocol in out\n"); 289 do { 290 statp++; 291 fprintf(VarTerm, " %-9s: %8lu, %8lu", 292 statp->name, statp->in_count, statp->out_count); 293 if (++cnt == 2) { 294 fprintf(VarTerm, "\n"); 295 cnt = 0; 296 } 297 } while (statp->number); 298 if (cnt) 299 fprintf(VarTerm, "\n"); 300 return (1); 301 } 302 303 int 304 ReportHdlcStatus() 305 { 306 struct hdlcstat *hp = &HdlcStat; 307 308 if (VarTerm) { 309 fprintf(VarTerm, "HDLC level errors\n\n"); 310 fprintf(VarTerm, "FCS: %u ADDR: %u COMMAND: %u PROTO: %u\n", 311 hp->badfcs, hp->badaddr, hp->badcommand, hp->unknownproto); 312 } 313 return 0; 314 } 315 316 static struct hdlcstat laststat; 317 318 void 319 HdlcErrorCheck() 320 { 321 struct hdlcstat *hp = &HdlcStat; 322 struct hdlcstat *op = &laststat; 323 324 if (bcmp(hp, op, sizeof(laststat))) { 325 LogPrintf(LogPHASE, "HDLC errors -> FCS: %u ADDR: %u COMD: %u PROTO: %u\n", 326 hp->badfcs - op->badfcs, hp->badaddr - op->badaddr, 327 hp->badcommand - op->badcommand, hp->unknownproto - op->unknownproto); 328 } 329 laststat = HdlcStat; 330 } 331 332 void 333 HdlcInput(struct mbuf * bp) 334 { 335 u_short fcs, proto; 336 u_char *cp, addr, ctrl; 337 struct protostat *statp; 338 339 LogDumpBp(LogHDLC, "HdlcInput:", bp); 340 if (DEV_IS_SYNC) 341 fcs = GOODFCS; 342 else 343 fcs = HdlcFcs(INITFCS, MBUF_CTOP(bp), bp->cnt); 344 HisLqrSave.SaveInOctets += bp->cnt + 1; 345 346 LogPrintf(LogDEBUG, "HdlcInput: fcs = %04x (%s)\n", 347 fcs, (fcs == GOODFCS) ? "good" : "bad"); 348 if (fcs != GOODFCS) { 349 HisLqrSave.SaveInErrors++; 350 LogPrintf(LogDEBUG, "HdlcInput: Bad FCS\n"); 351 HdlcStat.badfcs++; 352 pfree(bp); 353 return; 354 } 355 if (!DEV_IS_SYNC) 356 bp->cnt -= 2; /* discard FCS part */ 357 358 if (bp->cnt < 2) { /* XXX: raise this bar ? */ 359 pfree(bp); 360 return; 361 } 362 cp = MBUF_CTOP(bp); 363 364 ifInPackets++; 365 ifInOctets += bp->cnt; 366 367 if (!LcpInfo.want_acfcomp) { 368 369 /* 370 * We expect that packet is not compressed. 371 */ 372 addr = *cp++; 373 if (addr != HDLC_ADDR) { 374 HisLqrSave.SaveInErrors++; 375 HdlcStat.badaddr++; 376 LogPrintf(LogDEBUG, "HdlcInput: addr %02x\n", *cp); 377 pfree(bp); 378 return; 379 } 380 ctrl = *cp++; 381 if (ctrl != HDLC_UI) { 382 HisLqrSave.SaveInErrors++; 383 HdlcStat.badcommand++; 384 LogPrintf(LogDEBUG, "HdlcInput: %02x\n", *cp); 385 pfree(bp); 386 return; 387 } 388 bp->offset += 2; 389 bp->cnt -= 2; 390 } else if (cp[0] == HDLC_ADDR && cp[1] == HDLC_UI) { 391 392 /* 393 * We can receive compressed packet, but peer still send uncompressed 394 * packet to me. 395 */ 396 cp += 2; 397 bp->offset += 2; 398 bp->cnt -= 2; 399 } 400 if (LcpInfo.want_protocomp) { 401 proto = 0; 402 cp--; 403 do { 404 cp++; 405 bp->offset++; 406 bp->cnt--; 407 proto = proto << 8; 408 proto += *cp; 409 } while (!(proto & 1)); 410 } else { 411 proto = *cp++ << 8; 412 proto |= *cp++; 413 bp->offset += 2; 414 bp->cnt -= 2; 415 } 416 417 for (statp = ProtocolStat; statp->number; statp++) 418 if (statp->number == proto) 419 break; 420 statp->in_count++; 421 HisLqrSave.SaveInPackets++; 422 423 DecodePacket(proto, bp); 424 } 425