hdlc.c revision 37994
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 1.34 1998/06/27 23:48:44 brian Exp $ 21 * 22 * TODO: 23 */ 24#include <sys/types.h> 25#include <netinet/in.h> 26#include <netinet/in_systm.h> 27#include <netinet/ip.h> 28#include <sys/un.h> 29 30#include <stdio.h> 31#include <string.h> 32#include <termios.h> 33 34#include "defs.h" 35#include "command.h" 36#include "mbuf.h" 37#include "log.h" 38#include "timer.h" 39#include "fsm.h" 40#include "lqr.h" 41#include "hdlc.h" 42#include "lcpproto.h" 43#include "iplist.h" 44#include "throughput.h" 45#include "slcompress.h" 46#include "ipcp.h" 47#include "ip.h" 48#include "vjcomp.h" 49#include "auth.h" 50#include "pap.h" 51#include "chap.h" 52#include "lcp.h" 53#include "async.h" 54#include "ccp.h" 55#include "link.h" 56#include "descriptor.h" 57#include "physical.h" 58#include "prompt.h" 59#include "chat.h" 60#include "mp.h" 61#include "datalink.h" 62#include "filter.h" 63#include "bundle.h" 64 65static u_int16_t const fcstab[256] = { 66 /* 00 */ 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, 67 /* 08 */ 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, 68 /* 10 */ 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, 69 /* 18 */ 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, 70 /* 20 */ 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, 71 /* 28 */ 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, 72 /* 30 */ 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, 73 /* 38 */ 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, 74 /* 40 */ 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, 75 /* 48 */ 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, 76 /* 50 */ 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, 77 /* 58 */ 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, 78 /* 60 */ 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, 79 /* 68 */ 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, 80 /* 70 */ 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, 81 /* 78 */ 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, 82 /* 80 */ 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, 83 /* 88 */ 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, 84 /* 90 */ 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, 85 /* 98 */ 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, 86 /* a0 */ 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, 87 /* a8 */ 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, 88 /* b0 */ 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, 89 /* b8 */ 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, 90 /* c0 */ 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, 91 /* c8 */ 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, 92 /* d0 */ 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, 93 /* d8 */ 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, 94 /* e0 */ 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, 95 /* e8 */ 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, 96 /* f0 */ 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, 97 /* f8 */ 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 98}; 99 100void 101hdlc_Init(struct hdlc *hdlc, struct lcp *lcp) 102{ 103 memset(hdlc, '\0', sizeof(struct hdlc)); 104 hdlc->lqm.owner = lcp; 105} 106 107/* 108 * HDLC FCS computation. Read RFC 1171 Appendix B and CCITT X.25 section 109 * 2.27 for further details. 110 */ 111inline u_short 112hdlc_Fcs(u_short fcs, u_char * cp, int len) 113{ 114 while (len--) 115 fcs = (fcs >> 8) ^ fcstab[(fcs ^ *cp++) & 0xff]; 116 return (fcs); 117} 118 119static inline u_short 120HdlcFcsBuf(u_short fcs, struct mbuf *m) 121{ 122 int len; 123 u_char *pos, *end; 124 125 len = mbuf_Length(m); 126 pos = MBUF_CTOP(m); 127 end = pos + m->cnt; 128 while (len--) { 129 fcs = (fcs >> 8) ^ fcstab[(fcs ^ *pos++) & 0xff]; 130 if (pos == end && len) { 131 m = m->next; 132 pos = MBUF_CTOP(m); 133 end = pos + m->cnt; 134 } 135 } 136 return (fcs); 137} 138 139void 140hdlc_Output(struct link *l, int pri, u_short proto, struct mbuf *bp) 141{ 142 struct physical *p = link2physical(l); 143 struct mbuf *mhp, *mfcs; 144 u_char *cp; 145 u_short fcs; 146 147 if (!p || physical_IsSync(p)) 148 mfcs = NULL; 149 else 150 mfcs = mbuf_Alloc(2, MB_HDLCOUT); 151 152 mhp = mbuf_Alloc(4, MB_HDLCOUT); 153 mhp->cnt = 0; 154 cp = MBUF_CTOP(mhp); 155 if (p && (proto == PROTO_LCP || l->lcp.his_acfcomp == 0)) { 156 *cp++ = HDLC_ADDR; 157 *cp++ = HDLC_UI; 158 mhp->cnt += 2; 159 } 160 161 /* 162 * If possible, compress protocol field. 163 */ 164 if (l->lcp.his_protocomp && (proto & 0xff00) == 0) { 165 *cp++ = proto; 166 mhp->cnt++; 167 } else { 168 *cp++ = proto >> 8; 169 *cp = proto & 0377; 170 mhp->cnt += 2; 171 } 172 173 mhp->next = bp; 174 175 if (!p) { 176 /* 177 * This is where we multiplex the data over our available physical 178 * links. We don't frame our logical link data. Instead we wait 179 * for the logical link implementation to chop our data up and pile 180 * it into the physical links by re-calling this function with the 181 * encapsulated fragments. 182 */ 183 link_Output(l, pri, mhp); 184 return; 185 } 186 187 /* Tack mfcs onto the end, then set bp back to the start of the data */ 188 while (bp->next != NULL) 189 bp = bp->next; 190 bp->next = mfcs; 191 bp = mhp->next; 192 193 p->hdlc.lqm.OutOctets += mbuf_Length(mhp) + 1; 194 p->hdlc.lqm.OutPackets++; 195 196 if (proto == PROTO_LQR) { 197 /* Overwrite the entire packet */ 198 struct lqrdata lqr; 199 200 lqr.MagicNumber = p->link.lcp.want_magic; 201 lqr.LastOutLQRs = p->hdlc.lqm.lqr.peer.PeerOutLQRs; 202 lqr.LastOutPackets = p->hdlc.lqm.lqr.peer.PeerOutPackets; 203 lqr.LastOutOctets = p->hdlc.lqm.lqr.peer.PeerOutOctets; 204 lqr.PeerInLQRs = p->hdlc.lqm.lqr.SaveInLQRs; 205 lqr.PeerInPackets = p->hdlc.lqm.SaveInPackets; 206 lqr.PeerInDiscards = p->hdlc.lqm.SaveInDiscards; 207 lqr.PeerInErrors = p->hdlc.lqm.SaveInErrors; 208 lqr.PeerInOctets = p->hdlc.lqm.SaveInOctets; 209 lqr.PeerOutPackets = p->hdlc.lqm.OutPackets; 210 lqr.PeerOutOctets = p->hdlc.lqm.OutOctets; 211 if (p->hdlc.lqm.lqr.peer.LastOutLQRs == p->hdlc.lqm.lqr.OutLQRs) { 212 /* 213 * only increment if it's the first time or we've got a reply 214 * from the last one 215 */ 216 lqr.PeerOutLQRs = ++p->hdlc.lqm.lqr.OutLQRs; 217 lqr_Dump(l->name, "Output", &lqr); 218 } else { 219 lqr.PeerOutLQRs = p->hdlc.lqm.lqr.OutLQRs; 220 lqr_Dump(l->name, "Output (again)", &lqr); 221 } 222 lqr_ChangeOrder(&lqr, (struct lqrdata *)MBUF_CTOP(bp)); 223 } 224 225 if (mfcs) { 226 mfcs->cnt = 0; 227 fcs = HdlcFcsBuf(INITFCS, mhp); 228 fcs = ~fcs; 229 cp = MBUF_CTOP(mfcs); 230 *cp++ = fcs & 0377; /* Low byte first!! */ 231 *cp++ = fcs >> 8; 232 mfcs->cnt = 2; 233 } 234 235 log_DumpBp(LogHDLC, "hdlc_Output", mhp); 236 237 link_ProtocolRecord(l, proto, PROTO_OUT); 238 log_Printf(LogDEBUG, "hdlc_Output: proto = 0x%04x\n", proto); 239 240 if (physical_IsSync(p)) 241 link_Output(l, pri, mhp); /* Send it raw */ 242 else 243 async_Output(pri, mhp, proto, p); 244} 245 246/* Check out the latest ``Assigned numbers'' rfc (rfc1700.txt) */ 247static struct { 248 u_short from; 249 u_short to; 250 const char *name; 251} protocols[] = { 252 { 0x0001, 0x0001, "Padding Protocol" }, 253 { 0x0003, 0x001f, "reserved (transparency inefficient)" }, 254 { 0x0021, 0x0021, "Internet Protocol" }, 255 { 0x0023, 0x0023, "OSI Network Layer" }, 256 { 0x0025, 0x0025, "Xerox NS IDP" }, 257 { 0x0027, 0x0027, "DECnet Phase IV" }, 258 { 0x0029, 0x0029, "Appletalk" }, 259 { 0x002b, 0x002b, "Novell IPX" }, 260 { 0x002d, 0x002d, "Van Jacobson Compressed TCP/IP" }, 261 { 0x002f, 0x002f, "Van Jacobson Uncompressed TCP/IP" }, 262 { 0x0031, 0x0031, "Bridging PDU" }, 263 { 0x0033, 0x0033, "Stream Protocol (ST-II)" }, 264 { 0x0035, 0x0035, "Banyan Vines" }, 265 { 0x0037, 0x0037, "reserved (until 1993)" }, 266 { 0x0039, 0x0039, "AppleTalk EDDP" }, 267 { 0x003b, 0x003b, "AppleTalk SmartBuffered" }, 268 { 0x003d, 0x003d, "Multi-Link" }, 269 { 0x003f, 0x003f, "NETBIOS Framing" }, 270 { 0x0041, 0x0041, "Cisco Systems" }, 271 { 0x0043, 0x0043, "Ascom Timeplex" }, 272 { 0x0045, 0x0045, "Fujitsu Link Backup and Load Balancing (LBLB)" }, 273 { 0x0047, 0x0047, "DCA Remote Lan" }, 274 { 0x0049, 0x0049, "Serial Data Transport Protocol (PPP-SDTP)" }, 275 { 0x004b, 0x004b, "SNA over 802.2" }, 276 { 0x004d, 0x004d, "SNA" }, 277 { 0x004f, 0x004f, "IP6 Header Compression" }, 278 { 0x0051, 0x0051, "KNX Bridging Data" }, 279 { 0x0053, 0x0053, "Encryption" }, 280 { 0x0055, 0x0055, "Individual Link Encryption" }, 281 { 0x006f, 0x006f, "Stampede Bridging" }, 282 { 0x0071, 0x0071, "BAP Bandwidth Allocation Protocol" }, 283 { 0x0073, 0x0073, "MP+ Protocol" }, 284 { 0x007d, 0x007d, "reserved (Control Escape)" }, 285 { 0x007f, 0x007f, "reserved (compression inefficient)" }, 286 { 0x00cf, 0x00cf, "reserved (PPP NLPID)" }, 287 { 0x00fb, 0x00fb, "compression on single link in multilink group" }, 288 { 0x00fd, 0x00fd, "1st choice compression" }, 289 { 0x00ff, 0x00ff, "reserved (compression inefficient)" }, 290 { 0x0200, 0x02ff, "(compression inefficient)" }, 291 { 0x0201, 0x0201, "802.1d Hello Packets" }, 292 { 0x0203, 0x0203, "IBM Source Routing BPDU" }, 293 { 0x0205, 0x0205, "DEC LANBridge100 Spanning Tree" }, 294 { 0x0207, 0x0207, "Cisco Discovery Protocol" }, 295 { 0x0209, 0x0209, "Netcs Twin Routing" }, 296 { 0x0231, 0x0231, "Luxcom" }, 297 { 0x0233, 0x0233, "Sigma Network Systems" }, 298 { 0x0235, 0x0235, "Apple Client Server Protocol" }, 299 { 0x1e00, 0x1eff, "(compression inefficient)" }, 300 { 0x4001, 0x4001, "Cray Communications Control Protocol" }, 301 { 0x4003, 0x4003, "CDPD Mobile Network Registration Protocol" }, 302 { 0x4021, 0x4021, "Stacker LZS" }, 303 { 0x8001, 0x801f, "Not Used - reserved" }, 304 { 0x8021, 0x8021, "Internet Protocol Control Protocol" }, 305 { 0x8023, 0x8023, "OSI Network Layer Control Protocol" }, 306 { 0x8025, 0x8025, "Xerox NS IDP Control Protocol" }, 307 { 0x8027, 0x8027, "DECnet Phase IV Control Protocol" }, 308 { 0x8029, 0x8029, "Appletalk Control Protocol" }, 309 { 0x802b, 0x802b, "Novell IPX Control Protocol" }, 310 { 0x802d, 0x802d, "reserved" }, 311 { 0x802f, 0x802f, "reserved" }, 312 { 0x8031, 0x8031, "Bridging NCP" }, 313 { 0x8033, 0x8033, "Stream Protocol Control Protocol" }, 314 { 0x8035, 0x8035, "Banyan Vines Control Protocol" }, 315 { 0x8037, 0x8037, "reserved till 1993" }, 316 { 0x8039, 0x8039, "reserved" }, 317 { 0x803b, 0x803b, "reserved" }, 318 { 0x803d, 0x803d, "Multi-Link Control Protocol" }, 319 { 0x803f, 0x803f, "NETBIOS Framing Control Protocol" }, 320 { 0x8041, 0x8041, "Cisco Systems Control Protocol" }, 321 { 0x8043, 0x8043, "Ascom Timeplex" }, 322 { 0x8045, 0x8045, "Fujitsu LBLB Control Protocol" }, 323 { 0x8047, 0x8047, "DCA Remote Lan Network Control Protocol (RLNCP)" }, 324 { 0x8049, 0x8049, "Serial Data Control Protocol (PPP-SDCP)" }, 325 { 0x804b, 0x804b, "SNA over 802.2 Control Protocol" }, 326 { 0x804d, 0x804d, "SNA Control Protocol" }, 327 { 0x804f, 0x804f, "IP6 Header Compression Control Protocol" }, 328 { 0x8051, 0x8051, "KNX Bridging Control Protocol" }, 329 { 0x8053, 0x8053, "Encryption Control Protocol" }, 330 { 0x8055, 0x8055, "Individual Link Encryption Control Protocol" }, 331 { 0x806f, 0x806f, "Stampede Bridging Control Protocol" }, 332 { 0x8073, 0x8073, "MP+ Control Protocol" }, 333 { 0x8071, 0x8071, "BACP Bandwidth Allocation Control Protocol" }, 334 { 0x807d, 0x807d, "Not Used - reserved" }, 335 { 0x80cf, 0x80cf, "Not Used - reserved" }, 336 { 0x80fb, 0x80fb, "compression on single link in multilink group control" }, 337 { 0x80fd, 0x80fd, "Compression Control Protocol" }, 338 { 0x80ff, 0x80ff, "Not Used - reserved" }, 339 { 0x8207, 0x8207, "Cisco Discovery Protocol Control" }, 340 { 0x8209, 0x8209, "Netcs Twin Routing" }, 341 { 0x8235, 0x8235, "Apple Client Server Protocol Control" }, 342 { 0xc021, 0xc021, "Link Control Protocol" }, 343 { 0xc023, 0xc023, "Password Authentication Protocol" }, 344 { 0xc025, 0xc025, "Link Quality Report" }, 345 { 0xc027, 0xc027, "Shiva Password Authentication Protocol" }, 346 { 0xc029, 0xc029, "CallBack Control Protocol (CBCP)" }, 347 { 0xc081, 0xc081, "Container Control Protocol" }, 348 { 0xc223, 0xc223, "Challenge Handshake Authentication Protocol" }, 349 { 0xc225, 0xc225, "RSA Authentication Protocol" }, 350 { 0xc227, 0xc227, "Extensible Authentication Protocol" }, 351 { 0xc26f, 0xc26f, "Stampede Bridging Authorization Protocol" }, 352 { 0xc281, 0xc281, "Proprietary Authentication Protocol" }, 353 { 0xc283, 0xc283, "Proprietary Authentication Protocol" }, 354 { 0xc481, 0xc481, "Proprietary Node ID Authentication Protocol" } 355}; 356 357#define NPROTOCOLS (sizeof protocols/sizeof protocols[0]) 358 359const char * 360hdlc_Protocol2Nam(u_short proto) 361{ 362 int f; 363 364 for (f = 0; f < NPROTOCOLS; f++) 365 if (proto >= protocols[f].from && proto <= protocols[f].to) 366 return protocols[f].name; 367 else if (proto < protocols[f].from) 368 break; 369 return "unrecognised protocol"; 370} 371 372void 373hdlc_DecodePacket(struct bundle *bundle, u_short proto, struct mbuf * bp, 374 struct link *l) 375{ 376 struct physical *p = link2physical(l); 377 u_char *cp; 378 const char *type; 379 380 log_Printf(LogDEBUG, "DecodePacket: proto = 0x%04x\n", proto); 381 382 /* decompress everything. CCP needs uncompressed data too */ 383 if ((bp = ccp_Decompress(&l->ccp, &proto, bp)) == NULL) 384 return; 385 386 switch (proto) { 387 case PROTO_LCP: 388 lcp_Input(&l->lcp, bp); 389 break; 390 case PROTO_PAP: 391 if (p) 392 pap_Input(bundle, bp, p); 393 else { 394 log_Printf(LogERROR, "DecodePacket: PAP: Not a physical link !\n"); 395 mbuf_Free(bp); 396 } 397 break; 398 case PROTO_LQR: 399 if (p) { 400 p->hdlc.lqm.lqr.SaveInLQRs++; 401 lqr_Input(p, bp); 402 } else { 403 log_Printf(LogERROR, "DecodePacket: LQR: Not a physical link !\n"); 404 mbuf_Free(bp); 405 } 406 break; 407 case PROTO_CHAP: 408 if (p) 409 chap_Input(bundle, bp, p); 410 else { 411 log_Printf(LogERROR, "DecodePacket: CHAP: Not a physical link !\n"); 412 mbuf_Free(bp); 413 } 414 break; 415 case PROTO_VJUNCOMP: 416 case PROTO_VJCOMP: 417 bp = vj_Input(&bundle->ncp.ipcp, bp, proto); 418 if (bp == NULL) 419 break; 420 /* fall down */ 421 case PROTO_IP: 422 ip_Input(bundle, bp); 423 break; 424 case PROTO_IPCP: 425 ipcp_Input(&bundle->ncp.ipcp, bundle, bp); 426 break; 427 case PROTO_CCP: 428 ccp_Input(&l->ccp, bundle, bp); 429 break; 430 case PROTO_MP: 431 if (bundle->ncp.mp.active) { 432 if (p) 433 mp_Input(&bundle->ncp.mp, bp, p); 434 else { 435 log_Printf(LogWARN, "DecodePacket: Can't do MP inside MP !\n"); 436 mbuf_Free(bp); 437 } 438 break; 439 } 440 /* Fall through */ 441 default: 442 switch (proto) { 443 case PROTO_MP: 444 case PROTO_COMPD: 445 case PROTO_ICOMPD: 446 type = "Unexpected"; 447 break; 448 default: 449 type = "Unknown"; 450 break; 451 } 452 log_Printf(LogPHASE, "%s protocol 0x%04x (%s)\n", type, proto, 453 hdlc_Protocol2Nam(proto)); 454 bp->offset -= 2; 455 bp->cnt += 2; 456 cp = MBUF_CTOP(bp); 457 lcp_SendProtoRej(&l->lcp, cp, bp->cnt); 458 if (p) { 459 p->hdlc.lqm.SaveInDiscards++; 460 p->hdlc.stats.unknownproto++; 461 } 462 mbuf_Free(bp); 463 break; 464 } 465} 466 467static int 468hdlc_GetProto(const u_char *cp, u_short *proto) 469{ 470 *proto = *cp; 471 if (!(*proto & 1)) { 472 *proto = (*proto << 8) | cp[1]; 473 return 2; 474 } 475 return 1; 476} 477 478void 479hdlc_Input(struct bundle *bundle, struct mbuf * bp, struct physical *physical) 480{ 481 u_short fcs, proto; 482 u_char *cp, addr, ctrl; 483 int n; 484 485 log_DumpBp(LogHDLC, "hdlc_Input:", bp); 486 if (physical_IsSync(physical)) 487 fcs = GOODFCS; 488 else 489 fcs = hdlc_Fcs(INITFCS, MBUF_CTOP(bp), bp->cnt); 490 physical->hdlc.lqm.SaveInOctets += bp->cnt + 1; 491 492 log_Printf(LogDEBUG, "%s: hdlc_Input: fcs = %04x (%s)\n", 493 physical->link.name, fcs, (fcs == GOODFCS) ? "good" : "BAD!"); 494 if (fcs != GOODFCS) { 495 physical->hdlc.lqm.SaveInErrors++; 496 physical->hdlc.stats.badfcs++; 497 mbuf_Free(bp); 498 return; 499 } 500 if (!physical_IsSync(physical)) 501 bp->cnt -= 2; /* discard FCS part */ 502 503 if (bp->cnt < 2) { /* XXX: raise this bar ? */ 504 mbuf_Free(bp); 505 return; 506 } 507 cp = MBUF_CTOP(bp); 508 509 if (!physical->link.lcp.want_acfcomp) { 510 /* We expect the packet not to be compressed */ 511 addr = *cp++; 512 if (addr != HDLC_ADDR) { 513 physical->hdlc.lqm.SaveInErrors++; 514 physical->hdlc.stats.badaddr++; 515 log_Printf(LogDEBUG, "hdlc_Input: addr %02x\n", *cp); 516 mbuf_Free(bp); 517 return; 518 } 519 ctrl = *cp++; 520 if (ctrl != HDLC_UI) { 521 physical->hdlc.lqm.SaveInErrors++; 522 physical->hdlc.stats.badcommand++; 523 log_Printf(LogDEBUG, "hdlc_Input: %02x\n", *cp); 524 mbuf_Free(bp); 525 return; 526 } 527 bp->offset += 2; 528 bp->cnt -= 2; 529 } else if (cp[0] == HDLC_ADDR && cp[1] == HDLC_UI) { 530 /* 531 * We can receive compressed packets, but the peer still sends 532 * uncompressed packets ! 533 */ 534 cp += 2; 535 bp->offset += 2; 536 bp->cnt -= 2; 537 } 538 539 n = hdlc_GetProto(cp, &proto); 540 bp->offset += n; 541 bp->cnt -= n; 542 if (!physical->link.lcp.want_protocomp && n == 1) 543 log_Printf(LogHDLC, "%s: Warning: received a proto-compressed packet !\n", 544 physical->link.name); 545 546 link_ProtocolRecord(&physical->link, proto, PROTO_IN); 547 physical->hdlc.lqm.SaveInPackets++; 548 549 hdlc_DecodePacket(bundle, proto, bp, &physical->link); 550} 551 552/* 553 * Detect a HDLC frame 554 */ 555 556static const char *FrameHeaders[] = { 557 "\176\377\003\300\041", 558 "\176\377\175\043\300\041", 559 "\176\177\175\043\100\041", 560 "\176\175\337\175\043\300\041", 561 "\176\175\137\175\043\100\041", 562 NULL, 563}; 564 565u_char * 566hdlc_Detect(struct physical *physical, u_char *cp, int n) 567{ 568 const char *fp, **hp; 569 char *ptr; 570 571 cp[n] = '\0'; /* be sure to null terminate */ 572 ptr = NULL; 573 for (hp = FrameHeaders; *hp; hp++) { 574 fp = *hp; 575 if (physical_IsSync(physical)) 576 fp++; 577 ptr = strstr((char *)cp, fp); /* XXX: cp may have embedded NULs */ 578 if (ptr) 579 break; 580 } 581 return (u_char *)ptr; 582} 583 584int 585hdlc_ReportStatus(struct cmdargs const *arg) 586{ 587 struct hdlc *hdlc = &arg->cx->physical->hdlc; 588 589 prompt_Printf(arg->prompt, "%s HDLC level errors:\n", arg->cx->name); 590 prompt_Printf(arg->prompt, " Bad Frame Check Sequence fields: %u\n", 591 hdlc->stats.badfcs); 592 prompt_Printf(arg->prompt, " Bad address (!= 0x%02x) fields: %u\n", 593 HDLC_ADDR, hdlc->stats.badaddr); 594 prompt_Printf(arg->prompt, " Bad command (!= 0x%02x) fields: %u\n", 595 HDLC_UI, hdlc->stats.badcommand); 596 prompt_Printf(arg->prompt, " Unrecognised protocol fields: %u\n", 597 hdlc->stats.unknownproto); 598 return 0; 599} 600 601static void 602hdlc_ReportTime(void *v) 603{ 604 /* Moan about HDLC errors */ 605 struct hdlc *hdlc = (struct hdlc *)v; 606 607 timer_Stop(&hdlc->ReportTimer); 608 609 if (memcmp(&hdlc->laststats, &hdlc->stats, sizeof hdlc->stats)) { 610 log_Printf(LogPHASE, 611 "%s: HDLC errors -> FCS: %u, ADDR: %u, COMD: %u, PROTO: %u\n", 612 hdlc->lqm.owner->fsm.link->name, 613 hdlc->stats.badfcs - hdlc->laststats.badfcs, 614 hdlc->stats.badaddr - hdlc->laststats.badaddr, 615 hdlc->stats.badcommand - hdlc->laststats.badcommand, 616 hdlc->stats.unknownproto - hdlc->laststats.unknownproto); 617 hdlc->laststats = hdlc->stats; 618 } 619 620 timer_Start(&hdlc->ReportTimer); 621} 622 623void 624hdlc_StartTimer(struct hdlc *hdlc) 625{ 626 timer_Stop(&hdlc->ReportTimer); 627 hdlc->ReportTimer.load = 60 * SECTICKS; 628 hdlc->ReportTimer.arg = hdlc; 629 hdlc->ReportTimer.func = hdlc_ReportTime; 630 hdlc->ReportTimer.name = "hdlc"; 631 timer_Start(&hdlc->ReportTimer); 632} 633 634void 635hdlc_StopTimer(struct hdlc *hdlc) 636{ 637 timer_Stop(&hdlc->ReportTimer); 638} 639