1 /*-
2 * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
3 * based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
4 * Internet Initiative Japan, Inc (IIJ)
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: src/usr.sbin/ppp/hdlc.c,v 1.46.2.2 2002/09/01 02:12:27 brian Exp $
29 */
30
31 #include <sys/param.h>
32 #include <sys/un.h>
33
34 #include <stdarg.h>
35 #include <stdio.h>
36 #include <string.h>
37 #include <termios.h>
38
39 #include "defs.h"
40 #include "layer.h"
41 #include "command.h"
42 #include "mbuf.h"
43 #include "log.h"
44 #include "timer.h"
45 #include "fsm.h"
46 #include "lqr.h"
47 #include "hdlc.h"
48 #include "throughput.h"
49 #include "auth.h"
50 #include "lcp.h"
51 #include "async.h"
52 #include "ccp.h"
53 #include "link.h"
54 #include "descriptor.h"
55 #include "chap.h"
56 #include "physical.h"
57 #include "prompt.h"
58 #include "chat.h"
59 #include "mp.h"
60 #include "cbcp.h"
61 #include "datalink.h"
62
63 static u_int16_t 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
hdlc_Init(struct hdlc * hdlc,struct lcp * lcp)99 hdlc_Init(struct hdlc *hdlc, struct lcp *lcp)
100 {
101 memset(hdlc, '\0', sizeof(struct hdlc));
102 hdlc->lqm.owner = lcp;
103 }
104
105 /*
106 * HDLC FCS computation. Read RFC 1171 Appendix B and CCITT X.25 section
107 * 2.27 for further details.
108 */
109 u_short
hdlc_Fcs(u_char * cp,size_t len)110 hdlc_Fcs(u_char *cp, size_t len)
111 {
112 u_short fcs = INITFCS;
113
114 while (len--)
115 fcs = (fcs >> 8) ^ fcstab[(fcs ^ *cp++) & 0xff];
116
117 return fcs;
118 }
119
120 static inline u_short
HdlcFcsBuf(u_short fcs,struct mbuf * m)121 HdlcFcsBuf(u_short fcs, struct mbuf *m)
122 {
123 int len;
124 u_char *pos, *end;
125
126 len = m_length(m);
127 pos = MBUF_CTOP(m);
128 end = pos + m->m_len;
129 while (len--) {
130 fcs = (fcs >> 8) ^ fcstab[(fcs ^ *pos++) & 0xff];
131 if (pos == end && len) {
132 m = m->m_next;
133 pos = MBUF_CTOP(m);
134 end = pos + m->m_len;
135 }
136 }
137 return (fcs);
138 }
139
140 static struct mbuf *
hdlc_LayerPush(struct bundle * bundle __unused,struct link * l __unused,struct mbuf * bp,int pri __unused,u_short * proto __unused)141 hdlc_LayerPush(struct bundle *bundle __unused, struct link *l __unused,
142 struct mbuf *bp, int pri __unused, u_short *proto __unused)
143 {
144 struct mbuf *last;
145 u_char *cp;
146 u_short fcs;
147
148 m_settype(bp, MB_HDLCOUT);
149 fcs = HdlcFcsBuf(INITFCS, bp);
150 fcs = ~fcs;
151
152 for (last = bp; last->m_next; last = last->m_next)
153 ;
154
155 if (last->m_size - last->m_offset - last->m_len >= 2) {
156 cp = MBUF_CTOP(last) + last->m_len;
157 last->m_len += 2;
158 } else {
159 struct mbuf *tail = m_get(2, MB_HDLCOUT);
160 last->m_next = tail;
161 cp = MBUF_CTOP(tail);
162 }
163
164 *cp++ = fcs & 0377; /* Low byte first (nothing like consistency) */
165 *cp++ = fcs >> 8;
166
167 log_DumpBp(LogHDLC, "hdlc_Output", bp);
168
169 return bp;
170 }
171
172 /* Check out the latest ``Assigned numbers'' rfc (rfc1700.txt) */
173 static struct {
174 u_short from;
175 u_short to;
176 const char *name;
177 } protocols[] = {
178 { 0x0001, 0x0001, "Padding Protocol" },
179 { 0x0003, 0x001f, "reserved (transparency inefficient)" },
180 { 0x0021, 0x0021, "Internet Protocol" },
181 { 0x0023, 0x0023, "OSI Network Layer" },
182 { 0x0025, 0x0025, "Xerox NS IDP" },
183 { 0x0027, 0x0027, "DECnet Phase IV" },
184 { 0x0029, 0x0029, "Appletalk" },
185 { 0x002b, 0x002b, "Novell IPX" },
186 { 0x002d, 0x002d, "Van Jacobson Compressed TCP/IP" },
187 { 0x002f, 0x002f, "Van Jacobson Uncompressed TCP/IP" },
188 { 0x0031, 0x0031, "Bridging PDU" },
189 { 0x0033, 0x0033, "Stream Protocol (ST-II)" },
190 { 0x0035, 0x0035, "Banyan Vines" },
191 { 0x0037, 0x0037, "reserved (until 1993)" },
192 { 0x0039, 0x0039, "AppleTalk EDDP" },
193 { 0x003b, 0x003b, "AppleTalk SmartBuffered" },
194 { 0x003d, 0x003d, "Multi-Link" },
195 { 0x003f, 0x003f, "NETBIOS Framing" },
196 { 0x0041, 0x0041, "Cisco Systems" },
197 { 0x0043, 0x0043, "Ascom Timeplex" },
198 { 0x0045, 0x0045, "Fujitsu Link Backup and Load Balancing (LBLB)" },
199 { 0x0047, 0x0047, "DCA Remote Lan" },
200 { 0x0049, 0x0049, "Serial Data Transport Protocol (PPP-SDTP)" },
201 { 0x004b, 0x004b, "SNA over 802.2" },
202 { 0x004d, 0x004d, "SNA" },
203 { 0x004f, 0x004f, "IP6 Header Compression" },
204 { 0x0051, 0x0051, "KNX Bridging Data" },
205 { 0x0053, 0x0053, "Encryption" },
206 { 0x0055, 0x0055, "Individual Link Encryption" },
207 { 0x0057, 0x0057, "Internet Protocol V6" },
208 { 0x006f, 0x006f, "Stampede Bridging" },
209 { 0x0071, 0x0071, "BAP Bandwidth Allocation Protocol" },
210 { 0x0073, 0x0073, "MP+ Protocol" },
211 { 0x007d, 0x007d, "reserved (Control Escape)" },
212 { 0x007f, 0x007f, "reserved (compression inefficient)" },
213 { 0x00cf, 0x00cf, "reserved (PPP NLPID)" },
214 { 0x00fb, 0x00fb, "compression on single link in multilink group" },
215 { 0x00fd, 0x00fd, "1st choice compression" },
216 { 0x00ff, 0x00ff, "reserved (compression inefficient)" },
217 { 0x0200, 0x02ff, "(compression inefficient)" },
218 { 0x0201, 0x0201, "802.1d Hello Packets" },
219 { 0x0203, 0x0203, "IBM Source Routing BPDU" },
220 { 0x0205, 0x0205, "DEC LANBridge100 Spanning Tree" },
221 { 0x0207, 0x0207, "Cisco Discovery Protocol" },
222 { 0x0209, 0x0209, "Netcs Twin Routing" },
223 { 0x0231, 0x0231, "Luxcom" },
224 { 0x0233, 0x0233, "Sigma Network Systems" },
225 { 0x0235, 0x0235, "Apple Client Server Protocol" },
226 { 0x1e00, 0x1eff, "(compression inefficient)" },
227 { 0x4001, 0x4001, "Cray Communications Control Protocol" },
228 { 0x4003, 0x4003, "CDPD Mobile Network Registration Protocol" },
229 { 0x4021, 0x4021, "Stacker LZS" },
230 { 0x8001, 0x801f, "Not Used - reserved" },
231 { 0x8021, 0x8021, "Internet Protocol Control Protocol" },
232 { 0x8023, 0x8023, "OSI Network Layer Control Protocol" },
233 { 0x8025, 0x8025, "Xerox NS IDP Control Protocol" },
234 { 0x8027, 0x8027, "DECnet Phase IV Control Protocol" },
235 { 0x8029, 0x8029, "Appletalk Control Protocol" },
236 { 0x802b, 0x802b, "Novell IPX Control Protocol" },
237 { 0x802d, 0x802d, "reserved" },
238 { 0x802f, 0x802f, "reserved" },
239 { 0x8031, 0x8031, "Bridging NCP" },
240 { 0x8033, 0x8033, "Stream Protocol Control Protocol" },
241 { 0x8035, 0x8035, "Banyan Vines Control Protocol" },
242 { 0x8037, 0x8037, "reserved till 1993" },
243 { 0x8039, 0x8039, "reserved" },
244 { 0x803b, 0x803b, "reserved" },
245 { 0x803d, 0x803d, "Multi-Link Control Protocol" },
246 { 0x803f, 0x803f, "NETBIOS Framing Control Protocol" },
247 { 0x8041, 0x8041, "Cisco Systems Control Protocol" },
248 { 0x8043, 0x8043, "Ascom Timeplex" },
249 { 0x8045, 0x8045, "Fujitsu LBLB Control Protocol" },
250 { 0x8047, 0x8047, "DCA Remote Lan Network Control Protocol (RLNCP)" },
251 { 0x8049, 0x8049, "Serial Data Control Protocol (PPP-SDCP)" },
252 { 0x804b, 0x804b, "SNA over 802.2 Control Protocol" },
253 { 0x804d, 0x804d, "SNA Control Protocol" },
254 { 0x804f, 0x804f, "IP6 Header Compression Control Protocol" },
255 { 0x8051, 0x8051, "KNX Bridging Control Protocol" },
256 { 0x8053, 0x8053, "Encryption Control Protocol" },
257 { 0x8055, 0x8055, "Individual Link Encryption Control Protocol" },
258 { 0x8057, 0x8057, "Internet Protocol V6 Control Protocol" },
259 { 0x806f, 0x806f, "Stampede Bridging Control Protocol" },
260 { 0x8073, 0x8073, "MP+ Control Protocol" },
261 { 0x8071, 0x8071, "BACP Bandwidth Allocation Control Protocol" },
262 { 0x807d, 0x807d, "Not Used - reserved" },
263 { 0x80cf, 0x80cf, "Not Used - reserved" },
264 { 0x80fb, 0x80fb, "compression on single link in multilink group control" },
265 { 0x80fd, 0x80fd, "Compression Control Protocol" },
266 { 0x80ff, 0x80ff, "Not Used - reserved" },
267 { 0x8207, 0x8207, "Cisco Discovery Protocol Control" },
268 { 0x8209, 0x8209, "Netcs Twin Routing" },
269 { 0x8235, 0x8235, "Apple Client Server Protocol Control" },
270 { 0xc021, 0xc021, "Link Control Protocol" },
271 { 0xc023, 0xc023, "Password Authentication Protocol" },
272 { 0xc025, 0xc025, "Link Quality Report" },
273 { 0xc027, 0xc027, "Shiva Password Authentication Protocol" },
274 { 0xc029, 0xc029, "CallBack Control Protocol (CBCP)" },
275 { 0xc081, 0xc081, "Container Control Protocol" },
276 { 0xc223, 0xc223, "Challenge Handshake Authentication Protocol" },
277 { 0xc225, 0xc225, "RSA Authentication Protocol" },
278 { 0xc227, 0xc227, "Extensible Authentication Protocol" },
279 { 0xc26f, 0xc26f, "Stampede Bridging Authorization Protocol" },
280 { 0xc281, 0xc281, "Proprietary Authentication Protocol" },
281 { 0xc283, 0xc283, "Proprietary Authentication Protocol" },
282 { 0xc481, 0xc481, "Proprietary Node ID Authentication Protocol" }
283 };
284
285 #define NPROTOCOLS NELEM(protocols)
286
287 const char *
hdlc_Protocol2Nam(u_short proto)288 hdlc_Protocol2Nam(u_short proto)
289 {
290 unsigned f;
291
292 for (f = 0; f < NPROTOCOLS; f++)
293 if (proto >= protocols[f].from && proto <= protocols[f].to)
294 return protocols[f].name;
295 else if (proto < protocols[f].from)
296 break;
297 return "unrecognised protocol";
298 }
299
300 static struct mbuf *
hdlc_LayerPull(struct bundle * b __unused,struct link * l,struct mbuf * bp,u_short * proto __unused)301 hdlc_LayerPull(struct bundle *b __unused, struct link *l, struct mbuf *bp,
302 u_short *proto __unused)
303 {
304 struct physical *p = link2physical(l);
305 u_short fcs;
306 int len;
307
308 if (!p) {
309 log_Printf(LogERROR, "Can't Pull a hdlc packet from a logical link\n");
310 return bp;
311 }
312
313 log_DumpBp(LogHDLC, "hdlc_LayerPull:", bp);
314
315 fcs = hdlc_Fcs(MBUF_CTOP(bp), bp->m_len);
316
317 log_Printf(LogDEBUG, "%s: hdlc_LayerPull: fcs = %04x (%s)\n",
318 p->link.name, fcs, (fcs == GOODFCS) ? "good" : "BAD!");
319
320 if (fcs != GOODFCS) {
321 p->hdlc.lqm.SaveInErrors++;
322 p->hdlc.stats.badfcs++;
323 m_freem(bp);
324 return NULL;
325 }
326
327 p->hdlc.lqm.SaveInOctets += bp->m_len + 1;
328 p->hdlc.lqm.SaveInPackets++;
329
330 len = m_length(bp);
331 if (len < 4) { /* rfc1662 section 4.3 */
332 m_freem(bp);
333 bp = NULL;
334 }
335
336 bp = m_adj(bp, -2); /* discard the FCS */
337 m_settype(bp, MB_HDLCIN);
338
339 return bp;
340 }
341
342 /* Detect a HDLC frame */
343
344 static const struct frameheader {
345 const u_char *data;
346 int len;
347 } FrameHeaders[] = {
348 { "\176\377\003\300\041", 5 },
349 { "\176\377\175\043\300\041", 6 },
350 { "\176\177\175\043\100\041", 6 },
351 { "\176\175\337\175\043\300\041", 7 },
352 { "\176\175\137\175\043\100\041", 7 },
353 { NULL, 0 }
354 };
355
356 int
hdlc_Detect(u_char const ** cp,unsigned n,int issync)357 hdlc_Detect(u_char const **cp, unsigned n, int issync)
358 {
359 const struct frameheader *fh;
360 const u_char *h;
361 size_t len, cmp;
362
363 while (n) {
364 for (fh = FrameHeaders; fh->len; fh++) {
365 h = issync ? fh->data + 1 : fh->data;
366 len = issync ? fh->len - 1 : fh->len;
367 cmp = n >= len ? len : n;
368 if (memcmp(*cp, h, cmp) == 0)
369 return cmp == len;
370 }
371 n--;
372 (*cp)++;
373 }
374
375 return 0;
376 }
377
378 int
hdlc_ReportStatus(struct cmdargs const * arg)379 hdlc_ReportStatus(struct cmdargs const *arg)
380 {
381 struct hdlc *hdlc = &arg->cx->physical->hdlc;
382
383 prompt_Printf(arg->prompt, "%s HDLC level errors:\n", arg->cx->name);
384 prompt_Printf(arg->prompt, " Bad Frame Check Sequence fields: %u\n",
385 hdlc->stats.badfcs);
386 prompt_Printf(arg->prompt, " Bad address (!= 0x%02x) fields: %u\n",
387 HDLC_ADDR, hdlc->stats.badaddr);
388 prompt_Printf(arg->prompt, " Bad command (!= 0x%02x) fields: %u\n",
389 HDLC_UI, hdlc->stats.badcommand);
390 prompt_Printf(arg->prompt, " Unrecognised protocol fields: %u\n",
391 hdlc->stats.unknownproto);
392 return 0;
393 }
394
395 static void
hdlc_ReportTime(void * v)396 hdlc_ReportTime(void *v)
397 {
398 /* Moan about HDLC errors */
399 struct hdlc *hdlc = (struct hdlc *)v;
400
401 timer_Stop(&hdlc->ReportTimer);
402
403 if (memcmp(&hdlc->laststats, &hdlc->stats, sizeof hdlc->stats)) {
404 log_Printf(LogPHASE,
405 "%s: HDLC errors -> FCS: %u, ADDR: %u, COMD: %u, PROTO: %u\n",
406 hdlc->lqm.owner->fsm.link->name,
407 hdlc->stats.badfcs - hdlc->laststats.badfcs,
408 hdlc->stats.badaddr - hdlc->laststats.badaddr,
409 hdlc->stats.badcommand - hdlc->laststats.badcommand,
410 hdlc->stats.unknownproto - hdlc->laststats.unknownproto);
411 hdlc->laststats = hdlc->stats;
412 }
413
414 timer_Start(&hdlc->ReportTimer);
415 }
416
417 void
hdlc_StartTimer(struct hdlc * hdlc)418 hdlc_StartTimer(struct hdlc *hdlc)
419 {
420 timer_Stop(&hdlc->ReportTimer);
421 hdlc->ReportTimer.load = 60 * SECTICKS;
422 hdlc->ReportTimer.arg = hdlc;
423 hdlc->ReportTimer.func = hdlc_ReportTime;
424 hdlc->ReportTimer.name = "hdlc";
425 timer_Start(&hdlc->ReportTimer);
426 }
427
428 void
hdlc_StopTimer(struct hdlc * hdlc)429 hdlc_StopTimer(struct hdlc *hdlc)
430 {
431 timer_Stop(&hdlc->ReportTimer);
432 }
433
434 struct layer hdlclayer = { LAYER_HDLC, "hdlc", hdlc_LayerPush, hdlc_LayerPull };
435