2 * ccp.c - PPP Compression Control Protocol.
4 * Copyright (c) 1994 The Australian National University.
7 * Permission to use, copy, modify, and distribute this software and its
8 * documentation is hereby granted, provided that the above copyright
9 * notice appears in all copies. This software is provided without any
10 * warranty, express or implied. The Australian National University
11 * makes no representations about the suitability of this software for
14 * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
15 * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
16 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
17 * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
20 * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
21 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
22 * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
23 * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
24 * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
28 #define RCSID "$Id: ccp.c,v 1.32 2001/03/08 05:11:11 paulus Exp $"
36 #include <net/ppp-comp.h>
38 static const char rcsid[] = RCSID;
41 * Unfortunately there is a bug in zlib which means that using a
42 * size of 8 (window size = 256) for Deflate compression will cause
43 * buffer overruns and kernel crashes in the deflate module.
44 * Until this is fixed we only accept sizes in the range 9 .. 15.
45 * Thanks to James Carlson for pointing this out.
47 #define DEFLATE_MIN_WORKS 9
50 * Command-line options.
52 static int setbsdcomp __P((char **));
53 static int setdeflate __P((char **));
54 static char bsd_value[8];
55 static char deflate_value[8];
57 static option_t ccp_option_list[] = {
58 { "noccp", o_bool, &ccp_protent.enabled_flag,
59 "Disable CCP negotiation" },
60 { "-ccp", o_bool, &ccp_protent.enabled_flag,
61 "Disable CCP negotiation", OPT_ALIAS },
63 { "bsdcomp", o_special, (void *)setbsdcomp,
64 "Request BSD-Compress packet compression",
65 OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, bsd_value },
66 { "nobsdcomp", o_bool, &ccp_wantoptions[0].bsd_compress,
67 "don't allow BSD-Compress", OPT_PRIOSUB | OPT_A2CLR,
68 &ccp_allowoptions[0].bsd_compress },
69 { "-bsdcomp", o_bool, &ccp_wantoptions[0].bsd_compress,
70 "don't allow BSD-Compress", OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLR,
71 &ccp_allowoptions[0].bsd_compress },
73 { "deflate", o_special, (void *)setdeflate,
74 "request Deflate compression",
75 OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, deflate_value },
76 { "nodeflate", o_bool, &ccp_wantoptions[0].deflate,
77 "don't allow Deflate compression", OPT_PRIOSUB | OPT_A2CLR,
78 &ccp_allowoptions[0].deflate },
79 { "-deflate", o_bool, &ccp_wantoptions[0].deflate,
80 "don't allow Deflate compression", OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLR,
81 &ccp_allowoptions[0].deflate },
83 { "nodeflatedraft", o_bool, &ccp_wantoptions[0].deflate_draft,
84 "don't use draft deflate #", OPT_A2COPY,
85 &ccp_allowoptions[0].deflate_draft },
87 { "predictor1", o_bool, &ccp_wantoptions[0].predictor_1,
88 "request Predictor-1", 1, &ccp_allowoptions[0].predictor_1, OPT_PRIO },
89 { "nopredictor1", o_bool, &ccp_wantoptions[0].predictor_1,
90 "don't allow Predictor-1", OPT_PRIOSUB | OPT_A2CLR,
91 &ccp_allowoptions[0].predictor_1 },
92 { "-predictor1", o_bool, &ccp_wantoptions[0].predictor_1,
93 "don't allow Predictor-1", OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLR,
94 &ccp_allowoptions[0].predictor_1 },
100 * Protocol entry points from main code.
102 static void ccp_init __P((int unit));
103 static void ccp_open __P((int unit));
104 static void ccp_close __P((int unit, char *));
105 static void ccp_lowerup __P((int unit));
106 static void ccp_lowerdown __P((int));
107 static void ccp_input __P((int unit, u_char *pkt, int len));
108 static void ccp_protrej __P((int unit));
109 static int ccp_printpkt __P((u_char *pkt, int len,
110 void (*printer) __P((void *, char *, ...)),
112 static void ccp_datainput __P((int unit, u_char *pkt, int len));
114 struct protent ccp_protent = {
134 fsm ccp_fsm[NUM_PPP];
135 ccp_options ccp_wantoptions[NUM_PPP]; /* what to request the peer to use */
136 ccp_options ccp_gotoptions[NUM_PPP]; /* what the peer agreed to do */
137 ccp_options ccp_allowoptions[NUM_PPP]; /* what we'll agree to do */
138 ccp_options ccp_hisoptions[NUM_PPP]; /* what we agreed to do */
141 * Callbacks for fsm code.
143 static void ccp_resetci __P((fsm *));
144 static int ccp_cilen __P((fsm *));
145 static void ccp_addci __P((fsm *, u_char *, int *));
146 static int ccp_ackci __P((fsm *, u_char *, int));
147 static int ccp_nakci __P((fsm *, u_char *, int));
148 static int ccp_rejci __P((fsm *, u_char *, int));
149 static int ccp_reqci __P((fsm *, u_char *, int *, int));
150 static void ccp_up __P((fsm *));
151 static void ccp_down __P((fsm *));
152 static int ccp_extcode __P((fsm *, int, int, u_char *, int));
153 static void ccp_rack_timeout __P((void *));
154 static char *method_name __P((ccp_options *, ccp_options *));
156 static fsm_callbacks ccp_callbacks = {
175 * Do we want / did we get any compression?
177 #define ANY_COMPRESS(opt) ((opt).deflate || (opt).bsd_compress \
178 || (opt).predictor_1 || (opt).predictor_2)
181 * Local state (mainly for handling reset-reqs and reset-acks).
183 static int ccp_localstate[NUM_PPP];
184 #define RACK_PENDING 1 /* waiting for reset-ack */
185 #define RREQ_REPEAT 2 /* send another reset-req if no reset-ack */
187 #define RACKTIMEOUT 1 /* second */
189 static int all_rejected[NUM_PPP]; /* we rejected all peer's options */
202 abits = rbits = strtol(str, &endp, 0);
203 if (endp != str && *endp == ',') {
205 abits = strtol(str, &endp, 0);
207 if (*endp != 0 || endp == str) {
208 option_error("invalid parameter '%s' for bsdcomp option", *argv);
211 if ((rbits != 0 && (rbits < BSD_MIN_BITS || rbits > BSD_MAX_BITS))
212 || (abits != 0 && (abits < BSD_MIN_BITS || abits > BSD_MAX_BITS))) {
213 option_error("bsdcomp option values must be 0 or %d .. %d",
214 BSD_MIN_BITS, BSD_MAX_BITS);
218 ccp_wantoptions[0].bsd_compress = 1;
219 ccp_wantoptions[0].bsd_bits = rbits;
221 ccp_wantoptions[0].bsd_compress = 0;
223 ccp_allowoptions[0].bsd_compress = 1;
224 ccp_allowoptions[0].bsd_bits = abits;
226 ccp_allowoptions[0].bsd_compress = 0;
227 slprintf(bsd_value, sizeof(bsd_value),
228 rbits == abits? "%d": "%d,%d", rbits, abits);
241 abits = rbits = strtol(str, &endp, 0);
242 if (endp != str && *endp == ',') {
244 abits = strtol(str, &endp, 0);
246 if (*endp != 0 || endp == str) {
247 option_error("invalid parameter '%s' for deflate option", *argv);
250 if ((rbits != 0 && (rbits < DEFLATE_MIN_SIZE || rbits > DEFLATE_MAX_SIZE))
251 || (abits != 0 && (abits < DEFLATE_MIN_SIZE
252 || abits > DEFLATE_MAX_SIZE))) {
253 option_error("deflate option values must be 0 or %d .. %d",
254 DEFLATE_MIN_SIZE, DEFLATE_MAX_SIZE);
257 if (rbits == DEFLATE_MIN_SIZE || abits == DEFLATE_MIN_SIZE) {
258 if (rbits == DEFLATE_MIN_SIZE)
259 rbits = DEFLATE_MIN_WORKS;
260 if (abits == DEFLATE_MIN_SIZE)
261 abits = DEFLATE_MIN_WORKS;
262 warn("deflate option value of %d changed to %d to avoid zlib bug",
263 DEFLATE_MIN_SIZE, DEFLATE_MIN_WORKS);
266 ccp_wantoptions[0].deflate = 1;
267 ccp_wantoptions[0].deflate_size = rbits;
269 ccp_wantoptions[0].deflate = 0;
271 ccp_allowoptions[0].deflate = 1;
272 ccp_allowoptions[0].deflate_size = abits;
274 ccp_allowoptions[0].deflate = 0;
275 slprintf(deflate_value, sizeof(deflate_value),
276 rbits == abits? "%d": "%d,%d", rbits, abits);
282 * ccp_init - initialize CCP.
288 fsm *f = &ccp_fsm[unit];
291 f->protocol = PPP_CCP;
292 f->callbacks = &ccp_callbacks;
295 memset(&ccp_wantoptions[unit], 0, sizeof(ccp_options));
296 memset(&ccp_gotoptions[unit], 0, sizeof(ccp_options));
297 memset(&ccp_allowoptions[unit], 0, sizeof(ccp_options));
298 memset(&ccp_hisoptions[unit], 0, sizeof(ccp_options));
300 ccp_wantoptions[0].deflate = 1;
301 ccp_wantoptions[0].deflate_size = DEFLATE_MAX_SIZE;
302 ccp_wantoptions[0].deflate_correct = 1;
303 ccp_wantoptions[0].deflate_draft = 1;
304 ccp_allowoptions[0].deflate = 1;
305 ccp_allowoptions[0].deflate_size = DEFLATE_MAX_SIZE;
306 ccp_allowoptions[0].deflate_correct = 1;
307 ccp_allowoptions[0].deflate_draft = 1;
309 ccp_wantoptions[0].bsd_compress = 1;
310 ccp_wantoptions[0].bsd_bits = BSD_MAX_BITS;
311 ccp_allowoptions[0].bsd_compress = 1;
312 ccp_allowoptions[0].bsd_bits = BSD_MAX_BITS;
314 ccp_allowoptions[0].predictor_1 = 1;
318 * ccp_open - CCP is allowed to come up.
324 fsm *f = &ccp_fsm[unit];
326 if (f->state != OPENED)
327 ccp_flags_set(unit, 1, 0);
330 * Find out which compressors the kernel supports before
331 * deciding whether to open in silent mode.
334 if (!ANY_COMPRESS(ccp_gotoptions[unit]))
335 f->flags |= OPT_SILENT;
341 * ccp_close - Terminate CCP.
344 ccp_close(unit, reason)
348 ccp_flags_set(unit, 0, 0);
349 fsm_close(&ccp_fsm[unit], reason);
353 * ccp_lowerup - we may now transmit CCP packets.
359 fsm_lowerup(&ccp_fsm[unit]);
363 * ccp_lowerdown - we may not transmit CCP packets.
369 fsm_lowerdown(&ccp_fsm[unit]);
373 * ccp_input - process a received CCP packet.
376 ccp_input(unit, p, len)
381 fsm *f = &ccp_fsm[unit];
385 * Check for a terminate-request so we can print a message.
388 fsm_input(f, p, len);
389 if (oldstate == OPENED && p[0] == TERMREQ && f->state != OPENED)
390 notice("Compression disabled by peer.");
393 * If we get a terminate-ack and we're not asking for compression,
396 if (oldstate == REQSENT && p[0] == TERMACK
397 && !ANY_COMPRESS(ccp_gotoptions[unit]))
398 ccp_close(unit, "No compression negotiated");
402 * Handle a CCP-specific code.
405 ccp_extcode(f, code, id, p, len)
413 if (f->state != OPENED)
415 /* send a reset-ack, which the transmitter will see and
416 reset its compression state. */
417 fsm_sdata(f, CCP_RESETACK, id, NULL, 0);
421 if (ccp_localstate[f->unit] & RACK_PENDING && id == f->reqid) {
422 ccp_localstate[f->unit] &= ~(RACK_PENDING | RREQ_REPEAT);
423 UNTIMEOUT(ccp_rack_timeout, f);
435 * ccp_protrej - peer doesn't talk CCP.
441 ccp_flags_set(unit, 0, 0);
442 fsm_lowerdown(&ccp_fsm[unit]);
446 * ccp_resetci - initialize at start of negotiation.
452 ccp_options *go = &ccp_gotoptions[f->unit];
455 *go = ccp_wantoptions[f->unit];
456 all_rejected[f->unit] = 0;
459 * Check whether the kernel knows about the various
460 * compression methods we might request.
462 if (go->bsd_compress) {
463 opt_buf[0] = CI_BSD_COMPRESS;
464 opt_buf[1] = CILEN_BSD_COMPRESS;
465 opt_buf[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, BSD_MIN_BITS);
466 if (ccp_test(f->unit, opt_buf, CILEN_BSD_COMPRESS, 0) <= 0)
467 go->bsd_compress = 0;
470 if (go->deflate_correct) {
471 opt_buf[0] = CI_DEFLATE;
472 opt_buf[1] = CILEN_DEFLATE;
473 opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_WORKS);
474 opt_buf[3] = DEFLATE_CHK_SEQUENCE;
475 if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0)
476 go->deflate_correct = 0;
478 if (go->deflate_draft) {
479 opt_buf[0] = CI_DEFLATE_DRAFT;
480 opt_buf[1] = CILEN_DEFLATE;
481 opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_WORKS);
482 opt_buf[3] = DEFLATE_CHK_SEQUENCE;
483 if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0)
484 go->deflate_draft = 0;
486 if (!go->deflate_correct && !go->deflate_draft)
489 if (go->predictor_1) {
490 opt_buf[0] = CI_PREDICTOR_1;
491 opt_buf[1] = CILEN_PREDICTOR_1;
492 if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_1, 0) <= 0)
495 if (go->predictor_2) {
496 opt_buf[0] = CI_PREDICTOR_2;
497 opt_buf[1] = CILEN_PREDICTOR_2;
498 if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_2, 0) <= 0)
504 * ccp_cilen - Return total length of our configuration info.
510 ccp_options *go = &ccp_gotoptions[f->unit];
512 return (go->bsd_compress? CILEN_BSD_COMPRESS: 0)
513 + (go->deflate? CILEN_DEFLATE: 0)
514 + (go->predictor_1? CILEN_PREDICTOR_1: 0)
515 + (go->predictor_2? CILEN_PREDICTOR_2: 0);
519 * ccp_addci - put our requests in a packet.
522 ccp_addci(f, p, lenp)
528 ccp_options *go = &ccp_gotoptions[f->unit];
532 * Add the compression types that we can receive, in decreasing
533 * preference order. Get the kernel to allocate the first one
534 * in case it gets Acked.
537 p[0] = go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT;
538 p[1] = CILEN_DEFLATE;
539 p[2] = DEFLATE_MAKE_OPT(go->deflate_size);
540 p[3] = DEFLATE_CHK_SEQUENCE;
542 res = ccp_test(f->unit, p, CILEN_DEFLATE, 0);
547 if (res < 0 || go->deflate_size <= DEFLATE_MIN_WORKS) {
552 p[2] = DEFLATE_MAKE_OPT(go->deflate_size);
554 if (p != p0 && go->deflate_correct && go->deflate_draft) {
555 p[0] = CI_DEFLATE_DRAFT;
556 p[1] = CILEN_DEFLATE;
557 p[2] = p[2 - CILEN_DEFLATE];
558 p[3] = DEFLATE_CHK_SEQUENCE;
562 if (go->bsd_compress) {
563 p[0] = CI_BSD_COMPRESS;
564 p[1] = CILEN_BSD_COMPRESS;
565 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
567 p += CILEN_BSD_COMPRESS; /* not the first option */
570 res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 0);
572 p += CILEN_BSD_COMPRESS;
575 if (res < 0 || go->bsd_bits <= BSD_MIN_BITS) {
576 go->bsd_compress = 0;
580 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
584 /* XXX Should Predictor 2 be preferable to Predictor 1? */
585 if (go->predictor_1) {
586 p[0] = CI_PREDICTOR_1;
587 p[1] = CILEN_PREDICTOR_1;
588 if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 0) <= 0) {
591 p += CILEN_PREDICTOR_1;
594 if (go->predictor_2) {
595 p[0] = CI_PREDICTOR_2;
596 p[1] = CILEN_PREDICTOR_2;
597 if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 0) <= 0) {
600 p += CILEN_PREDICTOR_2;
604 go->method = (p > p0)? p0[0]: -1;
610 * ccp_ackci - process a received configure-ack, and return
611 * 1 iff the packet was OK.
619 ccp_options *go = &ccp_gotoptions[f->unit];
623 if (len < CILEN_DEFLATE
624 || p[0] != (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT)
625 || p[1] != CILEN_DEFLATE
626 || p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
627 || p[3] != DEFLATE_CHK_SEQUENCE)
630 len -= CILEN_DEFLATE;
631 /* XXX Cope with first/fast ack */
634 if (go->deflate_correct && go->deflate_draft) {
635 if (len < CILEN_DEFLATE
636 || p[0] != CI_DEFLATE_DRAFT
637 || p[1] != CILEN_DEFLATE
638 || p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
639 || p[3] != DEFLATE_CHK_SEQUENCE)
642 len -= CILEN_DEFLATE;
645 if (go->bsd_compress) {
646 if (len < CILEN_BSD_COMPRESS
647 || p[0] != CI_BSD_COMPRESS || p[1] != CILEN_BSD_COMPRESS
648 || p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits))
650 p += CILEN_BSD_COMPRESS;
651 len -= CILEN_BSD_COMPRESS;
652 /* XXX Cope with first/fast ack */
653 if (p == p0 && len == 0)
656 if (go->predictor_1) {
657 if (len < CILEN_PREDICTOR_1
658 || p[0] != CI_PREDICTOR_1 || p[1] != CILEN_PREDICTOR_1)
660 p += CILEN_PREDICTOR_1;
661 len -= CILEN_PREDICTOR_1;
662 /* XXX Cope with first/fast ack */
663 if (p == p0 && len == 0)
666 if (go->predictor_2) {
667 if (len < CILEN_PREDICTOR_2
668 || p[0] != CI_PREDICTOR_2 || p[1] != CILEN_PREDICTOR_2)
670 p += CILEN_PREDICTOR_2;
671 len -= CILEN_PREDICTOR_2;
672 /* XXX Cope with first/fast ack */
673 if (p == p0 && len == 0)
683 * ccp_nakci - process received configure-nak.
684 * Returns 1 iff the nak was OK.
692 ccp_options *go = &ccp_gotoptions[f->unit];
693 ccp_options no; /* options we've seen already */
694 ccp_options try; /* options to ask for next time */
696 memset(&no, 0, sizeof(no));
699 if (go->deflate && len >= CILEN_DEFLATE
700 && p[0] == (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT)
701 && p[1] == CILEN_DEFLATE) {
704 * Peer wants us to use a different code size or something.
705 * Stop asking for Deflate if we don't understand his suggestion.
707 if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
708 || DEFLATE_SIZE(p[2]) < DEFLATE_MIN_WORKS
709 || p[3] != DEFLATE_CHK_SEQUENCE)
711 else if (DEFLATE_SIZE(p[2]) < go->deflate_size)
712 try.deflate_size = DEFLATE_SIZE(p[2]);
714 len -= CILEN_DEFLATE;
715 if (go->deflate_correct && go->deflate_draft
716 && len >= CILEN_DEFLATE && p[0] == CI_DEFLATE_DRAFT
717 && p[1] == CILEN_DEFLATE) {
719 len -= CILEN_DEFLATE;
723 if (go->bsd_compress && len >= CILEN_BSD_COMPRESS
724 && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) {
727 * Peer wants us to use a different number of bits
728 * or a different version.
730 if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION)
731 try.bsd_compress = 0;
732 else if (BSD_NBITS(p[2]) < go->bsd_bits)
733 try.bsd_bits = BSD_NBITS(p[2]);
734 p += CILEN_BSD_COMPRESS;
735 len -= CILEN_BSD_COMPRESS;
739 * Predictor-1 and 2 have no options, so they can't be Naked.
741 * There may be remaining options but we ignore them.
744 if (f->state != OPENED)
750 * ccp_rejci - reject some of our suggested compression methods.
758 ccp_options *go = &ccp_gotoptions[f->unit];
759 ccp_options try; /* options to request next time */
764 * Cope with empty configure-rejects by ceasing to send
765 * configure-requests.
767 if (len == 0 && all_rejected[f->unit])
770 if (go->deflate && len >= CILEN_DEFLATE
771 && p[0] == (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT)
772 && p[1] == CILEN_DEFLATE) {
773 if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
774 || p[3] != DEFLATE_CHK_SEQUENCE)
775 return 0; /* Rej is bad */
776 if (go->deflate_correct)
777 try.deflate_correct = 0;
779 try.deflate_draft = 0;
781 len -= CILEN_DEFLATE;
782 if (go->deflate_correct && go->deflate_draft
783 && len >= CILEN_DEFLATE && p[0] == CI_DEFLATE_DRAFT
784 && p[1] == CILEN_DEFLATE) {
785 if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
786 || p[3] != DEFLATE_CHK_SEQUENCE)
787 return 0; /* Rej is bad */
788 try.deflate_draft = 0;
790 len -= CILEN_DEFLATE;
792 if (!try.deflate_correct && !try.deflate_draft)
795 if (go->bsd_compress && len >= CILEN_BSD_COMPRESS
796 && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) {
797 if (p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits))
799 try.bsd_compress = 0;
800 p += CILEN_BSD_COMPRESS;
801 len -= CILEN_BSD_COMPRESS;
803 if (go->predictor_1 && len >= CILEN_PREDICTOR_1
804 && p[0] == CI_PREDICTOR_1 && p[1] == CILEN_PREDICTOR_1) {
806 p += CILEN_PREDICTOR_1;
807 len -= CILEN_PREDICTOR_1;
809 if (go->predictor_2 && len >= CILEN_PREDICTOR_2
810 && p[0] == CI_PREDICTOR_2 && p[1] == CILEN_PREDICTOR_2) {
812 p += CILEN_PREDICTOR_2;
813 len -= CILEN_PREDICTOR_2;
819 if (f->state != OPENED)
826 * ccp_reqci - processed a received configure-request.
827 * Returns CONFACK, CONFNAK or CONFREJ and the packet modified
831 ccp_reqci(f, p, lenp, dont_nak)
837 int ret, newret, res;
839 int len, clen, type, nb;
840 ccp_options *ho = &ccp_hisoptions[f->unit];
841 ccp_options *ao = &ccp_allowoptions[f->unit];
847 memset(ho, 0, sizeof(ccp_options));
848 ho->method = (len > 0)? p[0]: -1;
852 if (len < 2 || p[1] < 2 || p[1] > len) {
863 case CI_DEFLATE_DRAFT:
864 if (!ao->deflate || clen != CILEN_DEFLATE
865 || (!ao->deflate_correct && type == CI_DEFLATE)
866 || (!ao->deflate_draft && type == CI_DEFLATE_DRAFT)) {
872 ho->deflate_size = nb = DEFLATE_SIZE(p[2]);
873 if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
874 || p[3] != DEFLATE_CHK_SEQUENCE
875 || nb > ao->deflate_size || nb < DEFLATE_MIN_WORKS) {
878 p[2] = DEFLATE_MAKE_OPT(ao->deflate_size);
879 p[3] = DEFLATE_CHK_SEQUENCE;
880 /* fall through to test this #bits below */
886 * Check whether we can do Deflate with the window
887 * size they want. If the window is too big, reduce
888 * it until the kernel can cope and nak with that.
889 * We only check this for the first option.
893 res = ccp_test(f->unit, p, CILEN_DEFLATE, 1);
895 break; /* it's OK now */
896 if (res < 0 || nb == DEFLATE_MIN_WORKS || dont_nak) {
898 p[2] = DEFLATE_MAKE_OPT(ho->deflate_size);
903 p[2] = DEFLATE_MAKE_OPT(nb);
908 case CI_BSD_COMPRESS:
909 if (!ao->bsd_compress || clen != CILEN_BSD_COMPRESS) {
914 ho->bsd_compress = 1;
915 ho->bsd_bits = nb = BSD_NBITS(p[2]);
916 if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION
917 || nb > ao->bsd_bits || nb < BSD_MIN_BITS) {
920 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, ao->bsd_bits);
921 /* fall through to test this #bits below */
927 * Check whether we can do BSD-Compress with the code
928 * size they want. If the code size is too big, reduce
929 * it until the kernel can cope and nak with that.
930 * We only check this for the first option.
934 res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 1);
937 if (res < 0 || nb == BSD_MIN_BITS || dont_nak) {
939 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION,
945 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb);
951 if (!ao->predictor_1 || clen != CILEN_PREDICTOR_1) {
958 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 1) <= 0) {
964 if (!ao->predictor_2 || clen != CILEN_PREDICTOR_2) {
971 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 1) <= 0) {
981 if (newret == CONFNAK && dont_nak)
983 if (!(newret == CONFACK || (newret == CONFNAK && ret == CONFREJ))) {
984 /* we're returning this option */
985 if (newret == CONFREJ && ret == CONFNAK)
989 BCOPY(p, retp, clen);
997 if (ret != CONFACK) {
998 if (ret == CONFREJ && *lenp == retp - p0)
999 all_rejected[f->unit] = 1;
1007 * Make a string name for a compression method (or 2).
1010 method_name(opt, opt2)
1011 ccp_options *opt, *opt2;
1013 static char result[64];
1015 if (!ANY_COMPRESS(*opt))
1017 switch (opt->method) {
1019 case CI_DEFLATE_DRAFT:
1020 if (opt2 != NULL && opt2->deflate_size != opt->deflate_size)
1021 slprintf(result, sizeof(result), "Deflate%s (%d/%d)",
1022 (opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
1023 opt->deflate_size, opt2->deflate_size);
1025 slprintf(result, sizeof(result), "Deflate%s (%d)",
1026 (opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
1029 case CI_BSD_COMPRESS:
1030 if (opt2 != NULL && opt2->bsd_bits != opt->bsd_bits)
1031 slprintf(result, sizeof(result), "BSD-Compress (%d/%d)",
1032 opt->bsd_bits, opt2->bsd_bits);
1034 slprintf(result, sizeof(result), "BSD-Compress (%d)",
1037 case CI_PREDICTOR_1:
1038 return "Predictor 1";
1039 case CI_PREDICTOR_2:
1040 return "Predictor 2";
1042 slprintf(result, sizeof(result), "Method %d", opt->method);
1048 * CCP has come up - inform the kernel driver and log a message.
1054 ccp_options *go = &ccp_gotoptions[f->unit];
1055 ccp_options *ho = &ccp_hisoptions[f->unit];
1058 ccp_flags_set(f->unit, 1, 1);
1059 if (ANY_COMPRESS(*go)) {
1060 if (ANY_COMPRESS(*ho)) {
1061 if (go->method == ho->method) {
1062 notice("%s compression enabled", method_name(go, ho));
1064 strlcpy(method1, method_name(go, NULL), sizeof(method1));
1065 notice("%s / %s compression enabled",
1066 method1, method_name(ho, NULL));
1069 notice("%s receive compression enabled", method_name(go, NULL));
1070 } else if (ANY_COMPRESS(*ho))
1071 notice("%s transmit compression enabled", method_name(ho, NULL));
1075 * CCP has gone down - inform the kernel driver.
1081 if (ccp_localstate[f->unit] & RACK_PENDING)
1082 UNTIMEOUT(ccp_rack_timeout, f);
1083 ccp_localstate[f->unit] = 0;
1084 ccp_flags_set(f->unit, 1, 0);
1088 * Print the contents of a CCP packet.
1090 static char *ccp_codenames[] = {
1091 "ConfReq", "ConfAck", "ConfNak", "ConfRej",
1092 "TermReq", "TermAck", "CodeRej",
1093 NULL, NULL, NULL, NULL, NULL, NULL,
1094 "ResetReq", "ResetAck",
1098 ccp_printpkt(p, plen, printer, arg)
1101 void (*printer) __P((void *, char *, ...));
1104 u_char *p0, *optend;
1109 if (plen < HEADERLEN)
1113 len = (p[2] << 8) + p[3];
1114 if (len < HEADERLEN || len > plen)
1117 if (code >= 1 && code <= sizeof(ccp_codenames) / sizeof(char *)
1118 && ccp_codenames[code-1] != NULL)
1119 printer(arg, " %s", ccp_codenames[code-1]);
1121 printer(arg, " code=0x%x", code);
1122 printer(arg, " id=0x%x", id);
1131 /* print list of possible compression methods */
1135 if (optlen < 2 || optlen > len)
1139 optend = p + optlen;
1142 case CI_DEFLATE_DRAFT:
1143 if (optlen >= CILEN_DEFLATE) {
1144 printer(arg, "deflate%s %d",
1145 (code == CI_DEFLATE_DRAFT? "(old#)": ""),
1146 DEFLATE_SIZE(p[2]));
1147 if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL)
1148 printer(arg, " method %d", DEFLATE_METHOD(p[2]));
1149 if (p[3] != DEFLATE_CHK_SEQUENCE)
1150 printer(arg, " check %d", p[3]);
1154 case CI_BSD_COMPRESS:
1155 if (optlen >= CILEN_BSD_COMPRESS) {
1156 printer(arg, "bsd v%d %d", BSD_VERSION(p[2]),
1158 p += CILEN_BSD_COMPRESS;
1161 case CI_PREDICTOR_1:
1162 if (optlen >= CILEN_PREDICTOR_1) {
1163 printer(arg, "predictor 1");
1164 p += CILEN_PREDICTOR_1;
1167 case CI_PREDICTOR_2:
1168 if (optlen >= CILEN_PREDICTOR_2) {
1169 printer(arg, "predictor 2");
1170 p += CILEN_PREDICTOR_2;
1175 printer(arg, " %.2x", *p++);
1182 if (len > 0 && *p >= ' ' && *p < 0x7f) {
1183 print_string((char *)p, len, printer, arg);
1190 /* dump out the rest of the packet in hex */
1192 printer(arg, " %.2x", *p++);
1198 * We have received a packet that the decompressor failed to
1199 * decompress. Here we would expect to issue a reset-request, but
1200 * Motorola has a patent on resetting the compressor as a result of
1201 * detecting an error in the decompressed data after decompression.
1202 * (See US patent 5,130,993; international patent publication number
1203 * WO 91/10289; Australian patent 73296/91.)
1205 * So we ask the kernel whether the error was detected after
1206 * decompression; if it was, we take CCP down, thus disabling
1207 * compression :-(, otherwise we issue the reset-request.
1210 ccp_datainput(unit, pkt, len)
1218 if (f->state == OPENED) {
1219 if (ccp_fatal_error(unit)) {
1221 * Disable compression by taking CCP down.
1223 error("Lost compression sync: disabling compression");
1224 ccp_close(unit, "Lost compression sync");
1227 * Send a reset-request to reset the peer's compressor.
1228 * We don't do that if we are still waiting for an
1229 * acknowledgement to a previous reset-request.
1231 if (!(ccp_localstate[f->unit] & RACK_PENDING)) {
1232 fsm_sdata(f, CCP_RESETREQ, f->reqid = ++f->id, NULL, 0);
1233 TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
1234 ccp_localstate[f->unit] |= RACK_PENDING;
1236 ccp_localstate[f->unit] |= RREQ_REPEAT;
1242 * Timeout waiting for reset-ack.
1245 ccp_rack_timeout(arg)
1250 if (f->state == OPENED && ccp_localstate[f->unit] & RREQ_REPEAT) {
1251 fsm_sdata(f, CCP_RESETREQ, f->reqid, NULL, 0);
1252 TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
1253 ccp_localstate[f->unit] &= ~RREQ_REPEAT;
1255 ccp_localstate[f->unit] &= ~RACK_PENDING;