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 1.8 1996/01/30 20:04:31 phk 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 "vars.h" 30 #include "pred.h" 31 #include "modem.h" 32 #include "ccp.h" 33 34 struct hdlcstat { 35 int badfcs; 36 int badaddr; 37 int badcommand; 38 int unknownproto; 39 } HdlcStat; 40 41 static int ifOutPackets, ifOutOctets, ifOutLQRs; 42 static int ifInPackets, ifInOctets; 43 44 struct protostat { 45 u_short number; 46 char *name; 47 u_long in_count; 48 u_long out_count; 49 } ProtocolStat[] = { 50 { PROTO_IP, "IP" }, 51 { PROTO_VJUNCOMP, "VJ_UNCOMP" }, 52 { PROTO_VJCOMP, "VJ_COMP" }, 53 { PROTO_COMPD, "COMPD" }, 54 { PROTO_LCP, "LCP" }, 55 { PROTO_IPCP, "IPCP" }, 56 { PROTO_CCP, "CCP" }, 57 { PROTO_PAP, "PAP" }, 58 { PROTO_LQR, "LQR" }, 59 { PROTO_CHAP, "CHAP" }, 60 { 0, "Others" }, 61 }; 62 63 static u_short const fcstab[256] = { 64 /* 00 */ 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, 65 /* 08 */ 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, 66 /* 10 */ 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, 67 /* 18 */ 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, 68 /* 20 */ 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, 69 /* 28 */ 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, 70 /* 30 */ 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, 71 /* 38 */ 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, 72 /* 40 */ 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, 73 /* 48 */ 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, 74 /* 50 */ 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, 75 /* 58 */ 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, 76 /* 60 */ 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, 77 /* 68 */ 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, 78 /* 70 */ 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, 79 /* 78 */ 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, 80 /* 80 */ 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, 81 /* 88 */ 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, 82 /* 90 */ 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, 83 /* 98 */ 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, 84 /* a0 */ 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, 85 /* a8 */ 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, 86 /* b0 */ 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, 87 /* b8 */ 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, 88 /* c0 */ 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, 89 /* c8 */ 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, 90 /* d0 */ 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, 91 /* d8 */ 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, 92 /* e0 */ 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, 93 /* e8 */ 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, 94 /* f0 */ 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, 95 /* f8 */ 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 96 }; 97 98 void 99 HdlcInit() 100 { 101 ifInOctets = ifOutOctets = 0; 102 ifInPackets = ifOutPackets = 0; 103 ifOutLQRs = 0; 104 } 105 106 /* 107 * HDLC FCS computation. Read RFC 1171 Appendix B and CCITT X.25 section 108 * 2.27 for further details. 109 */ 110 inline u_short 111 HdlcFcs(fcs, cp, len) 112 u_short fcs; 113 u_char *cp; 114 int len; 115 { 116 while (len--) 117 fcs = (fcs >> 8) ^ fcstab[(fcs ^ *cp++) & 0xff]; 118 return(fcs); 119 } 120 121 void 122 HdlcOutput(int pri, u_short proto, struct mbuf *bp) 123 { 124 struct mbuf *mhp, *mfcs; 125 struct protostat *statp; 126 struct lqrdata *lqr; 127 u_char *cp; 128 u_short fcs; 129 130 if ((proto & 0xfff1) == 0x21) { /* Network Layer protocol */ 131 if (CcpFsm.state == ST_OPENED) { 132 Pred1Output(pri, proto, bp); 133 return; 134 } 135 } 136 if (DEV_IS_SYNC) 137 mfcs = NULLBUFF; 138 else 139 mfcs = mballoc(2, MB_HDLCOUT); 140 mhp = mballoc(4, MB_HDLCOUT); 141 mhp->cnt = 0; 142 cp = MBUF_CTOP(mhp); 143 if (proto == PROTO_LCP || LcpInfo.his_acfcomp == 0) { 144 *cp++ = HDLC_ADDR; 145 *cp++ = HDLC_UI; 146 mhp->cnt += 2; 147 } 148 /* 149 * If possible, compress protocol field. 150 */ 151 if (LcpInfo.his_protocomp && (proto & 0xff00) == 0) { 152 *cp++ = proto; 153 mhp->cnt++; 154 } else { 155 *cp++ = proto >> 8; 156 *cp = proto & 0377; 157 mhp->cnt += 2; 158 } 159 mhp->next = bp; 160 bp->next = mfcs; 161 162 lqr = &MyLqrData; 163 lqr->PeerOutPackets = ifOutPackets++; 164 ifOutOctets += plength(mhp) + 1; 165 lqr->PeerOutOctets = ifOutOctets; 166 167 if (proto == PROTO_LQR) { 168 lqr->MagicNumber = LcpInfo.want_magic; 169 lqr->LastOutLQRs = HisLqrData.PeerOutLQRs; 170 lqr->LastOutPackets = HisLqrData.PeerOutPackets; 171 lqr->LastOutOctets = HisLqrData.PeerOutOctets; 172 lqr->PeerInLQRs = HisLqrSave.SaveInLQRs; 173 lqr->PeerInPackets = HisLqrSave.SaveInPackets; 174 lqr->PeerInDiscards = HisLqrSave.SaveInDiscards; 175 lqr->PeerInErrors = HisLqrSave.SaveInErrors; 176 lqr->PeerInOctets = HisLqrSave.SaveInOctets; 177 lqr->PeerOutLQRs = ++ifOutLQRs; 178 LqrDump("LqrOutput", lqr); 179 LqrChangeOrder(lqr, (struct lqrdata *)(MBUF_CTOP(bp))); 180 } 181 182 if (!DEV_IS_SYNC) { 183 fcs = HdlcFcs(INITFCS, MBUF_CTOP(mhp), mhp->cnt); 184 fcs = HdlcFcs(fcs, MBUF_CTOP(bp), bp->cnt); 185 fcs = ~fcs; 186 cp = MBUF_CTOP(mfcs); 187 *cp++ = fcs & 0377; /* Low byte first!! */ 188 *cp++ = fcs >> 8; 189 } 190 191 LogDumpBp(LOG_HDLC, "HdlcOutput", mhp); 192 for (statp = ProtocolStat; statp->number; statp++) 193 if (statp->number == proto) 194 break; 195 statp->out_count++; 196 if (DEV_IS_SYNC) 197 ModemOutput(pri, mhp); 198 else 199 AsyncOutput(pri, mhp, proto); 200 } 201 202 void 203 DecodePacket(proto, bp) 204 u_short proto; 205 struct mbuf *bp; 206 { 207 #ifdef DEBUG 208 logprintf("proto = %04x\n", proto); 209 #endif 210 u_char *cp; 211 212 switch (proto) { 213 case PROTO_LCP: 214 LcpInput(bp); 215 break; 216 case PROTO_PAP: 217 PapInput(bp); 218 break; 219 case PROTO_LQR: 220 HisLqrSave.SaveInLQRs++; 221 LqrInput(bp); 222 break; 223 case PROTO_CHAP: 224 ChapInput(bp); 225 break; 226 case PROTO_VJUNCOMP: 227 case PROTO_VJCOMP: 228 bp = VjCompInput(bp, proto); 229 if (bp == NULLBUFF) { 230 break; 231 } 232 /* fall down */ 233 case PROTO_IP: 234 IpInput(bp); 235 break; 236 case PROTO_IPCP: 237 IpcpInput(bp); 238 break; 239 case PROTO_CCP: 240 CcpInput(bp); 241 break; 242 case PROTO_COMPD: 243 Pred1Input(bp); 244 break; 245 default: 246 LogPrintf(LOG_PHASE_BIT, "Unknown protocol 0x%04x\n", proto); 247 bp->offset -= 2; 248 bp->cnt += 2; 249 cp = MBUF_CTOP(bp); 250 LcpSendProtoRej(cp, bp->cnt); 251 HisLqrSave.SaveInDiscards++; 252 HdlcStat.unknownproto++; 253 pfree(bp); 254 break; 255 } 256 } 257 258 int 259 ReportProtStatus() 260 { 261 struct protostat *statp; 262 int cnt; 263 264 statp = ProtocolStat; 265 statp--; 266 cnt = 0; 267 printf(" Protocol in out Protocol in out\n"); 268 do { 269 statp++; 270 printf(" %-9s: %8lu, %8lu", 271 statp->name, statp->in_count, statp->out_count); 272 if (++cnt == 2) { 273 printf("\n"); 274 cnt = 0; 275 } 276 } while (statp->number); 277 if (cnt) 278 printf("\n"); 279 return(1); 280 } 281 282 int 283 ReportHdlcStatus() 284 { 285 struct hdlcstat *hp = &HdlcStat; 286 287 printf("HDLC level errors\n\n"); 288 printf("FCS: %u ADDR: %u COMMAND: %u PROTO: %u\n", 289 hp->badfcs, hp->badaddr, hp->badcommand, hp->unknownproto); 290 return(1); 291 } 292 293 static struct hdlcstat laststat; 294 295 void 296 HdlcErrorCheck() 297 { 298 struct hdlcstat *hp = &HdlcStat; 299 struct hdlcstat *op = &laststat; 300 301 if (bcmp(hp, op, sizeof(laststat))) { 302 LogPrintf(LOG_PHASE_BIT, "HDLC errors -> FCS: %u ADDR: %u COMD: %u PROTO: %u\n", 303 hp->badfcs - op->badfcs, hp->badaddr - op->badaddr, 304 hp->badcommand - op->badcommand, hp->unknownproto - op->unknownproto); 305 } 306 laststat = HdlcStat; 307 } 308 309 void 310 HdlcInput(struct mbuf *bp) 311 { 312 u_short fcs, proto; 313 u_char *cp, addr, ctrl; 314 struct protostat *statp; 315 316 LogDumpBp(LOG_HDLC, "HdlcInput:", bp); 317 if (DEV_IS_SYNC) 318 fcs = GOODFCS; 319 else 320 fcs = HdlcFcs(INITFCS, MBUF_CTOP(bp), bp->cnt); 321 HisLqrSave.SaveInOctets += bp->cnt + 1; 322 323 #ifdef DEBUG 324 logprintf("fcs = %04x (%s)\n", fcs, (fcs == GOODFCS)? "good" : "bad"); 325 #endif 326 if (fcs != GOODFCS) { 327 HisLqrSave.SaveInErrors++; 328 #ifdef DEBUG 329 logprintf("Bad FCS\n"); 330 #endif 331 HdlcStat.badfcs++; 332 pfree(bp); 333 return; 334 } 335 if (!DEV_IS_SYNC) 336 bp->cnt -= 2; /* discard FCS part */ 337 cp = MBUF_CTOP(bp); 338 339 ifInPackets++; 340 ifInOctets += bp->cnt; 341 342 if (!LcpInfo.want_acfcomp) { 343 /* 344 * We expect that packet is not compressed. 345 */ 346 addr = *cp++; 347 if (addr != HDLC_ADDR) { 348 HisLqrSave.SaveInErrors++; 349 HdlcStat.badaddr++; 350 #ifdef DEBUG 351 logprintf("addr %02x\n", *cp); 352 #endif 353 pfree(bp); 354 return; 355 } 356 357 ctrl = *cp++; 358 if (ctrl != HDLC_UI) { 359 HisLqrSave.SaveInErrors++; 360 HdlcStat.badcommand++; 361 #ifdef DEBUG 362 logprintf("command %02x\n", *cp); 363 #endif 364 pfree(bp); 365 return; 366 } 367 bp->offset += 2; 368 bp->cnt -= 2; 369 } else if (cp[0] == HDLC_ADDR && cp[1] == HDLC_UI) { 370 /* 371 * We can receive compressed packet, but peer still send 372 * uncompressed packet to me. 373 */ 374 cp += 2; 375 bp->offset += 2; 376 bp->cnt -= 2; 377 } 378 379 if (LcpInfo.want_protocomp) { 380 proto = 0; 381 cp--; 382 do { 383 cp++; bp->offset++; bp->cnt--; 384 proto = proto << 8; 385 proto += *cp; 386 } while (!(proto & 1)); 387 } else { 388 proto = *cp++ << 8; 389 proto |= *cp++; 390 bp->offset += 2; 391 bp->cnt -= 2; 392 } 393 394 for (statp = ProtocolStat; statp->number; statp++) 395 if (statp->number == proto) 396 break; 397 statp->in_count++; 398 HisLqrSave.SaveInPackets++; 399 400 DecodePacket(proto, bp); 401 } 402