2 * lcp.c - PPP Link Control Protocol.
4 * Copyright (c) 1989 Carnegie Mellon University.
7 * Redistribution and use in source and binary forms are permitted
8 * provided that the above copyright notice and this paragraph are
9 * duplicated in all such forms and that any documentation,
10 * advertising materials, and other materials related to such
11 * distribution and use acknowledge that the software was developed
12 * by Carnegie Mellon University. The name of the
13 * University may not be used to endorse or promote products derived
14 * from this software without specific prior written permission.
15 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
17 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
21 static char rcsid[] = "$Id: lcp.c,v 1.36 1999/03/16 22:54:41 paulus Exp $";
39 * LCP-related command-line options.
41 int lcp_echo_interval = 0; /* Interval between LCP echo-requests */
42 int lcp_echo_fails = 0; /* Tolerance to unanswered echo-requests */
44 static int setescape __P((char **));
46 static option_t lcp_option_list[] = {
48 { "noaccomp", o_bool, &lcp_wantoptions[0].neg_accompression,
49 "Disable address/control compression",
50 OPT_A2COPY, &lcp_allowoptions[0].neg_accompression },
51 { "-ac", o_bool, &lcp_wantoptions[0].neg_accompression,
52 "Disable address/control compression",
53 OPT_A2COPY, &lcp_allowoptions[0].neg_accompression },
54 { "default-asyncmap", o_bool, &lcp_wantoptions[0].neg_asyncmap,
55 "Disable asyncmap negotiation",
56 OPT_A2COPY, &lcp_allowoptions[0].neg_asyncmap },
57 { "-am", o_bool, &lcp_wantoptions[0].neg_asyncmap,
58 "Disable asyncmap negotiation",
59 OPT_A2COPY, &lcp_allowoptions[0].neg_asyncmap },
60 { "asyncmap", o_uint32, &lcp_wantoptions[0].asyncmap,
61 "Set asyncmap (for received packets)",
62 OPT_OR, &lcp_wantoptions[0].neg_asyncmap },
63 { "-as", o_uint32, &lcp_wantoptions[0].asyncmap,
64 "Set asyncmap (for received packets)",
65 OPT_OR, &lcp_wantoptions[0].neg_asyncmap },
66 { "nomagicnumber", o_bool, &lcp_wantoptions[0].neg_magicnumber,
67 "Disable magic number negotiation (looped-back line detection)",
68 OPT_A2COPY, &lcp_allowoptions[0].neg_magicnumber },
69 { "-mn", o_bool, &lcp_wantoptions[0].neg_magicnumber,
70 "Disable magic number negotiation (looped-back line detection)",
71 OPT_A2COPY, &lcp_allowoptions[0].neg_magicnumber },
72 { "default-mru", o_bool, &lcp_wantoptions[0].neg_mru,
73 "Disable MRU negotiation (use default 1500)",
74 OPT_A2COPY, &lcp_allowoptions[0].neg_mru },
75 { "-mru", o_bool, &lcp_wantoptions[0].neg_mru,
76 "Disable MRU negotiation (use default 1500)",
77 OPT_A2COPY, &lcp_allowoptions[0].neg_mru },
78 { "mru", o_int, &lcp_wantoptions[0].mru,
79 "Set MRU (maximum received packet size) for negotiation",
80 0, &lcp_wantoptions[0].neg_mru },
81 { "nopcomp", o_bool, &lcp_wantoptions[0].neg_pcompression,
82 "Disable protocol field compression",
83 OPT_A2COPY, &lcp_allowoptions[0].neg_pcompression },
84 { "-pc", o_bool, &lcp_wantoptions[0].neg_pcompression,
85 "Disable protocol field compression",
86 OPT_A2COPY, &lcp_allowoptions[0].neg_pcompression },
87 { "-p", o_bool, &lcp_wantoptions[0].passive,
88 "Set passive mode", 1 },
89 { "passive", o_bool, &lcp_wantoptions[0].passive,
90 "Set passive mode", 1 },
91 { "silent", o_bool, &lcp_wantoptions[0].silent,
92 "Set silent mode", 1 },
93 { "escape", o_special, setescape,
94 "List of character codes to escape on transmission" },
95 { "lcp-echo-failure", o_int, &lcp_echo_fails,
96 "Set number of consecutive echo failures to indicate link failure" },
97 { "lcp-echo-interval", o_int, &lcp_echo_interval,
98 "Set time in seconds between LCP echo requests" },
99 { "lcp-restart", o_int, &lcp_fsm[0].timeouttime,
100 "Set time in seconds between LCP retransmissions" },
101 { "lcp-max-terminate", o_int, &lcp_fsm[0].maxtermtransmits,
102 "Set maximum number of LCP terminate-request transmissions" },
103 { "lcp-max-configure", o_int, &lcp_fsm[0].maxconfreqtransmits,
104 "Set maximum number of LCP configure-request transmissions" },
105 { "lcp-max-failure", o_int, &lcp_fsm[0].maxnakloops,
106 "Set limit on number of LCP configure-naks" },
111 fsm lcp_fsm[NUM_PPP]; /* LCP fsm structure (global)*/
112 lcp_options lcp_wantoptions[NUM_PPP]; /* Options that we want to request */
113 lcp_options lcp_gotoptions[NUM_PPP]; /* Options that peer ack'd */
114 lcp_options lcp_allowoptions[NUM_PPP]; /* Options we allow peer to request */
115 lcp_options lcp_hisoptions[NUM_PPP]; /* Options that we ack'd */
116 u_int32_t xmit_accm[NUM_PPP][8]; /* extended transmit ACCM */
118 static u_int32_t lcp_echos_pending = 0; /* Number of outstanding echo msgs */
119 static u_int32_t lcp_echo_number = 0; /* ID number of next echo frame */
120 static u_int32_t lcp_echo_timer_running = 0; /* TRUE if a timer is running */
122 static u_char nak_buffer[PPP_MRU]; /* where we construct a nak packet */
125 * Callbacks for fsm code. (CI = Configuration Information)
127 static void lcp_resetci __P((fsm *)); /* Reset our CI */
128 static int lcp_cilen __P((fsm *)); /* Return length of our CI */
129 static void lcp_addci __P((fsm *, u_char *, int *)); /* Add our CI to pkt */
130 static int lcp_ackci __P((fsm *, u_char *, int)); /* Peer ack'd our CI */
131 static int lcp_nakci __P((fsm *, u_char *, int)); /* Peer nak'd our CI */
132 static int lcp_rejci __P((fsm *, u_char *, int)); /* Peer rej'd our CI */
133 static int lcp_reqci __P((fsm *, u_char *, int *, int)); /* Rcv peer CI */
134 static void lcp_up __P((fsm *)); /* We're UP */
135 static void lcp_down __P((fsm *)); /* We're DOWN */
136 static void lcp_starting __P((fsm *)); /* We need lower layer up */
137 static void lcp_finished __P((fsm *)); /* We need lower layer down */
138 static int lcp_extcode __P((fsm *, int, int, u_char *, int));
139 static void lcp_rprotrej __P((fsm *, u_char *, int));
142 * routines to send LCP echos to peer
145 static void lcp_echo_lowerup __P((int));
146 static void lcp_echo_lowerdown __P((int));
147 static void LcpEchoTimeout __P((void *));
148 static void lcp_received_echo_reply __P((fsm *, int, u_char *, int));
149 static void LcpSendEchoRequest __P((fsm *));
150 static void LcpLinkFailure __P((fsm *));
151 static void LcpEchoCheck __P((fsm *));
153 static fsm_callbacks lcp_callbacks = { /* LCP callback routines */
154 lcp_resetci, /* Reset our Configuration Information */
155 lcp_cilen, /* Length of our Configuration Information */
156 lcp_addci, /* Add our Configuration Information */
157 lcp_ackci, /* ACK our Configuration Information */
158 lcp_nakci, /* NAK our Configuration Information */
159 lcp_rejci, /* Reject our Configuration Information */
160 lcp_reqci, /* Request peer's Configuration Information */
161 lcp_up, /* Called when fsm reaches OPENED state */
162 lcp_down, /* Called when fsm leaves OPENED state */
163 lcp_starting, /* Called when we want the lower layer up */
164 lcp_finished, /* Called when we want the lower layer down */
165 NULL, /* Called when Protocol-Reject received */
166 NULL, /* Retransmission is necessary */
167 lcp_extcode, /* Called to handle LCP-specific codes */
168 "LCP" /* String name of protocol */
172 * Protocol entry points.
173 * Some of these are called directly.
176 static void lcp_init __P((int));
177 static void lcp_input __P((int, u_char *, int));
178 static void lcp_protrej __P((int));
179 static int lcp_printpkt __P((u_char *, int,
180 void (*) __P((void *, char *, ...)), void *));
182 struct protent lcp_protent = {
202 int lcp_loopbackfail = DEFLOOPBACKFAIL;
205 * Length of each type of configuration option (in octets)
209 #define CILEN_SHORT 4 /* CILEN_VOID + sizeof(short) */
210 #define CILEN_CHAP 5 /* CILEN_VOID + sizeof(short) + 1 */
211 #define CILEN_LONG 6 /* CILEN_VOID + sizeof(long) */
212 #define CILEN_LQR 8 /* CILEN_VOID + sizeof(short) + sizeof(long) */
215 #define CODENAME(x) ((x) == CONFACK ? "ACK" : \
216 (x) == CONFNAK ? "NAK" : "REJ")
220 * setescape - add chars to the set we escape on transmission.
232 n = strtol(p, &endp, 16);
234 option_error("escape parameter contains invalid hex number '%s'",
239 if (n < 0 || n == 0x5E || n > 0xFF) {
240 option_error("can't escape character 0x%x", n);
243 xmit_accm[0][n >> 5] |= 1 << (n & 0x1F);
244 while (*p == ',' || *p == ' ')
251 * lcp_init - Initialize LCP.
257 fsm *f = &lcp_fsm[unit];
258 lcp_options *wo = &lcp_wantoptions[unit];
259 lcp_options *ao = &lcp_allowoptions[unit];
262 f->protocol = PPP_LCP;
263 f->callbacks = &lcp_callbacks;
269 wo->restart = 0; /* Set to 1 in kernels or multi-line
273 wo->neg_asyncmap = 1;
275 wo->neg_chap = 0; /* Set to 1 on server */
276 wo->neg_upap = 0; /* Set to 1 on server */
277 wo->chap_mdtype = CHAP_DIGEST_MD5;
278 wo->neg_magicnumber = 1;
279 wo->neg_pcompression = 1;
280 wo->neg_accompression = 1;
281 wo->neg_lqr = 0; /* no LQR implementation yet */
286 ao->neg_asyncmap = 1;
289 ao->chap_mdtype = CHAP_DIGEST_MD5;
291 ao->neg_magicnumber = 1;
292 ao->neg_pcompression = 1;
293 ao->neg_accompression = 1;
294 ao->neg_lqr = 0; /* no LQR implementation yet */
301 memset(xmit_accm[unit], 0, sizeof(xmit_accm[0]));
302 xmit_accm[unit][3] = 0x60000000;
307 * lcp_open - LCP is allowed to come up.
313 fsm *f = &lcp_fsm[unit];
314 lcp_options *wo = &lcp_wantoptions[unit];
318 f->flags |= OPT_PASSIVE;
320 f->flags |= OPT_SILENT;
326 * lcp_close - Take LCP down.
329 lcp_close(unit, reason)
333 fsm *f = &lcp_fsm[unit];
335 if (phase != PHASE_DEAD)
336 phase = PHASE_TERMINATE;
337 if (f->state == STOPPED && f->flags & (OPT_PASSIVE|OPT_SILENT)) {
339 * This action is not strictly according to the FSM in RFC1548,
340 * but it does mean that the program terminates if you do a
341 * lcp_close() in passive/silent mode when a connection hasn't
348 fsm_close(&lcp_fsm[unit], reason);
353 * lcp_lowerup - The lower layer is up.
359 lcp_options *wo = &lcp_wantoptions[unit];
362 * Don't use A/C or protocol compression on transmission,
363 * but accept A/C and protocol compressed packets
364 * if we are going to ask for A/C and protocol compression.
366 ppp_set_xaccm(unit, xmit_accm[unit]);
367 ppp_send_config(unit, PPP_MRU, 0xffffffff, 0, 0);
368 ppp_recv_config(unit, PPP_MRU, 0xffffffff,
369 wo->neg_pcompression, wo->neg_accompression);
370 peer_mru[unit] = PPP_MRU;
371 lcp_allowoptions[unit].asyncmap = xmit_accm[unit][0];
373 fsm_lowerup(&lcp_fsm[unit]);
378 * lcp_lowerdown - The lower layer is down.
384 fsm_lowerdown(&lcp_fsm[unit]);
389 * lcp_input - Input LCP packet.
392 lcp_input(unit, p, len)
397 fsm *f = &lcp_fsm[unit];
399 fsm_input(f, p, len);
404 * lcp_extcode - Handle a LCP-specific code.
407 lcp_extcode(f, code, id, inp, len)
417 lcp_rprotrej(f, inp, len);
421 if (f->state != OPENED)
424 PUTLONG(lcp_gotoptions[f->unit].magicnumber, magp);
425 fsm_sdata(f, ECHOREP, id, inp, len);
429 lcp_received_echo_reply(f, id, inp, len);
443 * lcp_rprotrej - Receive an Protocol-Reject.
445 * Figure out which protocol is rejected and inform it.
448 lcp_rprotrej(f, inp, len)
454 struct protent *protp;
457 if (len < sizeof (u_short)) {
458 LCPDEBUG(("lcp_rprotrej: Rcvd short Protocol-Reject packet!"));
465 * Protocol-Reject packets received in any state other than the LCP
466 * OPENED state SHOULD be silently discarded.
468 if( f->state != OPENED ){
469 LCPDEBUG(("Protocol-Reject discarded: LCP in state %d", f->state));
474 * Upcall the proper Protocol-Reject routine.
476 for (i = 0; (protp = protocols[i]) != NULL; ++i)
477 if (protp->protocol == prot && protp->enabled_flag) {
478 (*protp->protrej)(f->unit);
482 warn("Protocol-Reject for unsupported protocol 0x%x", prot);
487 * lcp_protrej - A Protocol-Reject was received.
497 error("Received Protocol-Reject for LCP!");
498 fsm_protreject(&lcp_fsm[unit]);
503 * lcp_sprotrej - Send a Protocol-Reject for some protocol.
506 lcp_sprotrej(unit, p, len)
512 * Send back the protocol and the information field of the
513 * rejected packet. We only get here if LCP is in the OPENED state.
518 fsm_sdata(&lcp_fsm[unit], PROTREJ, ++lcp_fsm[unit].id,
524 * lcp_resetci - Reset our CI.
530 lcp_wantoptions[f->unit].magicnumber = magic();
531 lcp_wantoptions[f->unit].numloops = 0;
532 lcp_gotoptions[f->unit] = lcp_wantoptions[f->unit];
533 peer_mru[f->unit] = PPP_MRU;
539 * lcp_cilen - Return length of our CI.
545 lcp_options *go = &lcp_gotoptions[f->unit];
547 #define LENCIVOID(neg) ((neg) ? CILEN_VOID : 0)
548 #define LENCICHAP(neg) ((neg) ? CILEN_CHAP : 0)
549 #define LENCISHORT(neg) ((neg) ? CILEN_SHORT : 0)
550 #define LENCILONG(neg) ((neg) ? CILEN_LONG : 0)
551 #define LENCILQR(neg) ((neg) ? CILEN_LQR: 0)
552 #define LENCICBCP(neg) ((neg) ? CILEN_CBCP: 0)
554 * NB: we only ask for one of CHAP and UPAP, even if we will
557 return (LENCISHORT(go->neg_mru && go->mru != DEFMRU) +
558 LENCILONG(go->neg_asyncmap && go->asyncmap != 0xFFFFFFFF) +
559 LENCICHAP(go->neg_chap) +
560 LENCISHORT(!go->neg_chap && go->neg_upap) +
561 LENCILQR(go->neg_lqr) +
562 LENCICBCP(go->neg_cbcp) +
563 LENCILONG(go->neg_magicnumber) +
564 LENCIVOID(go->neg_pcompression) +
565 LENCIVOID(go->neg_accompression));
570 * lcp_addci - Add our desired CIs to a packet.
573 lcp_addci(f, ucp, lenp)
578 lcp_options *go = &lcp_gotoptions[f->unit];
579 u_char *start_ucp = ucp;
581 #define ADDCIVOID(opt, neg) \
584 PUTCHAR(CILEN_VOID, ucp); \
586 #define ADDCISHORT(opt, neg, val) \
589 PUTCHAR(CILEN_SHORT, ucp); \
590 PUTSHORT(val, ucp); \
592 #define ADDCICHAP(opt, neg, val, digest) \
595 PUTCHAR(CILEN_CHAP, ucp); \
596 PUTSHORT(val, ucp); \
597 PUTCHAR(digest, ucp); \
599 #define ADDCILONG(opt, neg, val) \
602 PUTCHAR(CILEN_LONG, ucp); \
605 #define ADDCILQR(opt, neg, val) \
608 PUTCHAR(CILEN_LQR, ucp); \
609 PUTSHORT(PPP_LQR, ucp); \
612 #define ADDCICHAR(opt, neg, val) \
615 PUTCHAR(CILEN_CHAR, ucp); \
619 ADDCISHORT(CI_MRU, go->neg_mru && go->mru != DEFMRU, go->mru);
620 ADDCILONG(CI_ASYNCMAP, go->neg_asyncmap && go->asyncmap != 0xFFFFFFFF,
622 ADDCICHAP(CI_AUTHTYPE, go->neg_chap, PPP_CHAP, go->chap_mdtype);
623 ADDCISHORT(CI_AUTHTYPE, !go->neg_chap && go->neg_upap, PPP_PAP);
624 ADDCILQR(CI_QUALITY, go->neg_lqr, go->lqr_period);
625 ADDCICHAR(CI_CALLBACK, go->neg_cbcp, CBCP_OPT);
626 ADDCILONG(CI_MAGICNUMBER, go->neg_magicnumber, go->magicnumber);
627 ADDCIVOID(CI_PCOMPRESSION, go->neg_pcompression);
628 ADDCIVOID(CI_ACCOMPRESSION, go->neg_accompression);
630 if (ucp - start_ucp != *lenp) {
631 /* this should never happen, because peer_mtu should be 1500 */
632 error("Bug in lcp_addci: wrong length");
638 * lcp_ackci - Ack our CIs.
639 * This should not modify any state if the Ack is bad.
651 lcp_options *go = &lcp_gotoptions[f->unit];
652 u_char cilen, citype, cichar;
657 * CIs must be in exactly the same order that we sent.
658 * Check packet length and CI length at each step.
659 * If we find any deviations, then this packet is bad.
661 #define ACKCIVOID(opt, neg) \
663 if ((len -= CILEN_VOID) < 0) \
665 GETCHAR(citype, p); \
667 if (cilen != CILEN_VOID || \
671 #define ACKCISHORT(opt, neg, val) \
673 if ((len -= CILEN_SHORT) < 0) \
675 GETCHAR(citype, p); \
677 if (cilen != CILEN_SHORT || \
680 GETSHORT(cishort, p); \
681 if (cishort != val) \
684 #define ACKCICHAR(opt, neg, val) \
686 if ((len -= CILEN_CHAR) < 0) \
688 GETCHAR(citype, p); \
690 if (cilen != CILEN_CHAR || \
693 GETCHAR(cichar, p); \
697 #define ACKCICHAP(opt, neg, val, digest) \
699 if ((len -= CILEN_CHAP) < 0) \
701 GETCHAR(citype, p); \
703 if (cilen != CILEN_CHAP || \
706 GETSHORT(cishort, p); \
707 if (cishort != val) \
709 GETCHAR(cichar, p); \
710 if (cichar != digest) \
713 #define ACKCILONG(opt, neg, val) \
715 if ((len -= CILEN_LONG) < 0) \
717 GETCHAR(citype, p); \
719 if (cilen != CILEN_LONG || \
722 GETLONG(cilong, p); \
726 #define ACKCILQR(opt, neg, val) \
728 if ((len -= CILEN_LQR) < 0) \
730 GETCHAR(citype, p); \
732 if (cilen != CILEN_LQR || \
735 GETSHORT(cishort, p); \
736 if (cishort != PPP_LQR) \
738 GETLONG(cilong, p); \
743 ACKCISHORT(CI_MRU, go->neg_mru && go->mru != DEFMRU, go->mru);
744 ACKCILONG(CI_ASYNCMAP, go->neg_asyncmap && go->asyncmap != 0xFFFFFFFF,
746 ACKCICHAP(CI_AUTHTYPE, go->neg_chap, PPP_CHAP, go->chap_mdtype);
747 ACKCISHORT(CI_AUTHTYPE, !go->neg_chap && go->neg_upap, PPP_PAP);
748 ACKCILQR(CI_QUALITY, go->neg_lqr, go->lqr_period);
749 ACKCICHAR(CI_CALLBACK, go->neg_cbcp, CBCP_OPT);
750 ACKCILONG(CI_MAGICNUMBER, go->neg_magicnumber, go->magicnumber);
751 ACKCIVOID(CI_PCOMPRESSION, go->neg_pcompression);
752 ACKCIVOID(CI_ACCOMPRESSION, go->neg_accompression);
755 * If there are any remaining CIs, then this packet is bad.
761 LCPDEBUG(("lcp_acki: received bad Ack!"));
767 * lcp_nakci - Peer has sent a NAK for some of our CIs.
768 * This should not modify any state if the Nak is bad
769 * or if LCP is in the OPENED state.
781 lcp_options *go = &lcp_gotoptions[f->unit];
782 lcp_options *wo = &lcp_wantoptions[f->unit];
783 u_char citype, cichar, *next;
786 lcp_options no; /* options we've seen Naks for */
787 lcp_options try; /* options to request next time */
791 BZERO(&no, sizeof(no));
795 * Any Nak'd CIs must be in exactly the same order that we sent.
796 * Check packet length and CI length at each step.
797 * If we find any deviations, then this packet is bad.
799 #define NAKCIVOID(opt, neg, code) \
801 len >= CILEN_VOID && \
802 p[1] == CILEN_VOID && \
805 INCPTR(CILEN_VOID, p); \
809 #define NAKCICHAP(opt, neg, code) \
811 len >= CILEN_CHAP && \
812 p[1] == CILEN_CHAP && \
816 GETSHORT(cishort, p); \
817 GETCHAR(cichar, p); \
821 #define NAKCICHAR(opt, neg, code) \
823 len >= CILEN_CHAR && \
824 p[1] == CILEN_CHAR && \
828 GETCHAR(cichar, p); \
832 #define NAKCISHORT(opt, neg, code) \
834 len >= CILEN_SHORT && \
835 p[1] == CILEN_SHORT && \
837 len -= CILEN_SHORT; \
839 GETSHORT(cishort, p); \
843 #define NAKCILONG(opt, neg, code) \
845 len >= CILEN_LONG && \
846 p[1] == CILEN_LONG && \
850 GETLONG(cilong, p); \
854 #define NAKCILQR(opt, neg, code) \
856 len >= CILEN_LQR && \
857 p[1] == CILEN_LQR && \
861 GETSHORT(cishort, p); \
862 GETLONG(cilong, p); \
868 * We don't care if they want to send us smaller packets than
869 * we want. Therefore, accept any MRU less than what we asked for,
870 * but then ignore the new value when setting the MRU in the kernel.
871 * If they send us a bigger MRU than what we asked, accept it, up to
872 * the limit of the default MRU we'd get if we didn't negotiate.
874 if (go->neg_mru && go->mru != DEFMRU) {
875 NAKCISHORT(CI_MRU, neg_mru,
876 if (cishort <= wo->mru || cishort <= DEFMRU)
882 * Add any characters they want to our (receive-side) asyncmap.
884 if (go->neg_asyncmap && go->asyncmap != 0xFFFFFFFF) {
885 NAKCILONG(CI_ASYNCMAP, neg_asyncmap,
886 try.asyncmap = go->asyncmap | cilong;
891 * If they've nak'd our authentication-protocol, check whether
892 * they are proposing a different protocol, or a different
893 * hash algorithm for CHAP.
895 if ((go->neg_chap || go->neg_upap)
896 && len >= CILEN_SHORT
897 && p[0] == CI_AUTHTYPE && p[1] >= CILEN_SHORT && p[1] <= len) {
900 no.neg_chap = go->neg_chap;
901 no.neg_upap = go->neg_upap;
903 GETSHORT(cishort, p);
904 if (cishort == PPP_PAP && cilen == CILEN_SHORT) {
906 * If we were asking for CHAP, they obviously don't want to do it.
907 * If we weren't asking for CHAP, then we were asking for PAP,
908 * in which case this Nak is bad.
914 } else if (cishort == PPP_CHAP && cilen == CILEN_CHAP) {
918 * We were asking for CHAP/MD5; they must want a different
919 * algorithm. If they can't do MD5, we'll have to stop
922 if (cichar != go->chap_mdtype)
926 * Stop asking for PAP if we were asking for it.
933 * We don't recognize what they're suggesting.
934 * Stop asking for what we were asking for.
940 p += cilen - CILEN_SHORT;
945 * If they can't cope with our link quality protocol, we'll have
946 * to stop asking for LQR. We haven't got any other protocol.
947 * If they Nak the reporting period, take their value XXX ?
949 NAKCILQR(CI_QUALITY, neg_lqr,
950 if (cishort != PPP_LQR)
953 try.lqr_period = cilong;
957 * Only implementing CBCP...not the rest of the callback options
959 NAKCICHAR(CI_CALLBACK, neg_cbcp,
964 * Check for a looped-back line.
966 NAKCILONG(CI_MAGICNUMBER, neg_magicnumber,
967 try.magicnumber = magic();
972 * Peer shouldn't send Nak for protocol compression or
973 * address/control compression requests; they should send
974 * a Reject instead. If they send a Nak, treat it as a Reject.
976 NAKCIVOID(CI_PCOMPRESSION, neg_pcompression,
977 try.neg_pcompression = 0;
979 NAKCIVOID(CI_ACCOMPRESSION, neg_accompression,
980 try.neg_accompression = 0;
984 * There may be remaining CIs, if the peer is requesting negotiation
985 * on an option that we didn't include in our request packet.
986 * If we see an option that we requested, or one we've already seen
987 * in this packet, then this packet is bad.
988 * If we wanted to respond by starting to negotiate on the requested
989 * option(s), we could, but we don't, because except for the
990 * authentication type and quality protocol, if we are not negotiating
991 * an option, it is because we were told not to.
992 * For the authentication type, the Nak from the peer means
993 * `let me authenticate myself with you' which is a bit pointless.
994 * For the quality protocol, the Nak means `ask me to send you quality
995 * reports', but if we didn't ask for them, we don't want them.
996 * An option we don't recognize represents the peer asking to
997 * negotiate some option we don't support, so ignore it.
999 while (len > CILEN_VOID) {
1002 if (cilen < CILEN_VOID || (len -= cilen) < 0)
1004 next = p + cilen - 2;
1008 if ((go->neg_mru && go->mru != DEFMRU)
1009 || no.neg_mru || cilen != CILEN_SHORT)
1011 GETSHORT(cishort, p);
1012 if (cishort < DEFMRU)
1016 if ((go->neg_asyncmap && go->asyncmap != 0xFFFFFFFF)
1017 || no.neg_asyncmap || cilen != CILEN_LONG)
1021 if (go->neg_chap || no.neg_chap || go->neg_upap || no.neg_upap)
1024 case CI_MAGICNUMBER:
1025 if (go->neg_magicnumber || no.neg_magicnumber ||
1026 cilen != CILEN_LONG)
1029 case CI_PCOMPRESSION:
1030 if (go->neg_pcompression || no.neg_pcompression
1031 || cilen != CILEN_VOID)
1034 case CI_ACCOMPRESSION:
1035 if (go->neg_accompression || no.neg_accompression
1036 || cilen != CILEN_VOID)
1040 if (go->neg_lqr || no.neg_lqr || cilen != CILEN_LQR)
1047 /* If there is still anything left, this packet is bad. */
1052 * OK, the Nak is good. Now we can update state.
1054 if (f->state != OPENED) {
1056 if (++try.numloops >= lcp_loopbackfail) {
1057 notice("Serial line is looped back.");
1058 lcp_close(f->unit, "Loopback detected");
1068 LCPDEBUG(("lcp_nakci: received bad Nak!"));
1074 * lcp_rejci - Peer has Rejected some of our CIs.
1075 * This should not modify any state if the Reject is bad
1076 * or if LCP is in the OPENED state.
1079 * 0 - Reject was bad.
1080 * 1 - Reject was good.
1083 lcp_rejci(f, p, len)
1088 lcp_options *go = &lcp_gotoptions[f->unit];
1092 lcp_options try; /* options to request next time */
1097 * Any Rejected CIs must be in exactly the same order that we sent.
1098 * Check packet length and CI length at each step.
1099 * If we find any deviations, then this packet is bad.
1101 #define REJCIVOID(opt, neg) \
1103 len >= CILEN_VOID && \
1104 p[1] == CILEN_VOID && \
1106 len -= CILEN_VOID; \
1107 INCPTR(CILEN_VOID, p); \
1110 #define REJCISHORT(opt, neg, val) \
1112 len >= CILEN_SHORT && \
1113 p[1] == CILEN_SHORT && \
1115 len -= CILEN_SHORT; \
1117 GETSHORT(cishort, p); \
1118 /* Check rejected value. */ \
1119 if (cishort != val) \
1123 #define REJCICHAP(opt, neg, val, digest) \
1125 len >= CILEN_CHAP && \
1126 p[1] == CILEN_CHAP && \
1128 len -= CILEN_CHAP; \
1130 GETSHORT(cishort, p); \
1131 GETCHAR(cichar, p); \
1132 /* Check rejected value. */ \
1133 if (cishort != val || cichar != digest) \
1138 #define REJCILONG(opt, neg, val) \
1140 len >= CILEN_LONG && \
1141 p[1] == CILEN_LONG && \
1143 len -= CILEN_LONG; \
1145 GETLONG(cilong, p); \
1146 /* Check rejected value. */ \
1147 if (cilong != val) \
1151 #define REJCILQR(opt, neg, val) \
1153 len >= CILEN_LQR && \
1154 p[1] == CILEN_LQR && \
1158 GETSHORT(cishort, p); \
1159 GETLONG(cilong, p); \
1160 /* Check rejected value. */ \
1161 if (cishort != PPP_LQR || cilong != val) \
1165 #define REJCICBCP(opt, neg, val) \
1167 len >= CILEN_CBCP && \
1168 p[1] == CILEN_CBCP && \
1170 len -= CILEN_CBCP; \
1172 GETCHAR(cichar, p); \
1173 /* Check rejected value. */ \
1174 if (cichar != val) \
1179 REJCISHORT(CI_MRU, neg_mru, go->mru);
1180 REJCILONG(CI_ASYNCMAP, neg_asyncmap, go->asyncmap);
1181 REJCICHAP(CI_AUTHTYPE, neg_chap, PPP_CHAP, go->chap_mdtype);
1182 if (!go->neg_chap) {
1183 REJCISHORT(CI_AUTHTYPE, neg_upap, PPP_PAP);
1185 REJCILQR(CI_QUALITY, neg_lqr, go->lqr_period);
1186 REJCICBCP(CI_CALLBACK, neg_cbcp, CBCP_OPT);
1187 REJCILONG(CI_MAGICNUMBER, neg_magicnumber, go->magicnumber);
1188 REJCIVOID(CI_PCOMPRESSION, neg_pcompression);
1189 REJCIVOID(CI_ACCOMPRESSION, neg_accompression);
1192 * If there are any remaining CIs, then this packet is bad.
1197 * Now we can update state.
1199 if (f->state != OPENED)
1204 LCPDEBUG(("lcp_rejci: received bad Reject!"));
1210 * lcp_reqci - Check the peer's requested CIs and send appropriate response.
1212 * Returns: CONFACK, CONFNAK or CONFREJ and input packet modified
1213 * appropriately. If reject_if_disagree is non-zero, doesn't return
1214 * CONFNAK; returns CONFREJ if it can't return CONFACK.
1217 lcp_reqci(f, inp, lenp, reject_if_disagree)
1219 u_char *inp; /* Requested CIs */
1220 int *lenp; /* Length of requested CIs */
1221 int reject_if_disagree;
1223 lcp_options *go = &lcp_gotoptions[f->unit];
1224 lcp_options *ho = &lcp_hisoptions[f->unit];
1225 lcp_options *ao = &lcp_allowoptions[f->unit];
1226 u_char *cip, *next; /* Pointer to current and next CIs */
1227 int cilen, citype, cichar; /* Parsed len, type, char value */
1228 u_short cishort; /* Parsed short value */
1229 u_int32_t cilong; /* Parse long value */
1230 int rc = CONFACK; /* Final packet return code */
1231 int orc; /* Individual option return code */
1232 u_char *p; /* Pointer to next char to parse */
1233 u_char *rejp; /* Pointer to next char in reject frame */
1234 u_char *nakp; /* Pointer to next char in Nak frame */
1235 int l = *lenp; /* Length left */
1238 * Reset all his options.
1240 BZERO(ho, sizeof(*ho));
1243 * Process all his options.
1249 orc = CONFACK; /* Assume success */
1250 cip = p = next; /* Remember begining of CI */
1251 if (l < 2 || /* Not enough data for CI header or */
1252 p[1] < 2 || /* CI length too small or */
1253 p[1] > l) { /* CI length too big? */
1254 LCPDEBUG(("lcp_reqci: bad CI length!"));
1255 orc = CONFREJ; /* Reject bad CI */
1256 cilen = l; /* Reject till end of packet */
1257 l = 0; /* Don't loop again */
1261 GETCHAR(citype, p); /* Parse CI type */
1262 GETCHAR(cilen, p); /* Parse CI length */
1263 l -= cilen; /* Adjust remaining length */
1264 next += cilen; /* Step to next CI */
1266 switch (citype) { /* Check CI type */
1268 if (!ao->neg_mru || /* Allow option? */
1269 cilen != CILEN_SHORT) { /* Check CI length */
1270 orc = CONFREJ; /* Reject CI */
1273 GETSHORT(cishort, p); /* Parse MRU */
1276 * He must be able to receive at least our minimum.
1277 * No need to check a maximum. If he sends a large number,
1278 * we'll just ignore it.
1280 if (cishort < MINMRU) {
1281 orc = CONFNAK; /* Nak CI */
1282 PUTCHAR(CI_MRU, nakp);
1283 PUTCHAR(CILEN_SHORT, nakp);
1284 PUTSHORT(MINMRU, nakp); /* Give him a hint */
1287 ho->neg_mru = 1; /* Remember he sent MRU */
1288 ho->mru = cishort; /* And remember value */
1292 if (!ao->neg_asyncmap ||
1293 cilen != CILEN_LONG) {
1300 * Asyncmap must have set at least the bits
1301 * which are set in lcp_allowoptions[unit].asyncmap.
1303 if ((ao->asyncmap & ~cilong) != 0) {
1305 PUTCHAR(CI_ASYNCMAP, nakp);
1306 PUTCHAR(CILEN_LONG, nakp);
1307 PUTLONG(ao->asyncmap | cilong, nakp);
1310 ho->neg_asyncmap = 1;
1311 ho->asyncmap = cilong;
1315 if (cilen < CILEN_SHORT ||
1316 !(ao->neg_upap || ao->neg_chap)) {
1318 * Reject the option if we're not willing to authenticate.
1323 GETSHORT(cishort, p);
1326 * Authtype must be UPAP or CHAP.
1328 * Note: if both ao->neg_upap and ao->neg_chap are set,
1329 * and the peer sends a Configure-Request with two
1330 * authenticate-protocol requests, one for CHAP and one
1331 * for UPAP, then we will reject the second request.
1332 * Whether we end up doing CHAP or UPAP depends then on
1333 * the ordering of the CIs in the peer's Configure-Request.
1336 if (cishort == PPP_PAP) {
1337 if (ho->neg_chap || /* we've already accepted CHAP */
1338 cilen != CILEN_SHORT) {
1339 LCPDEBUG(("lcp_reqci: rcvd AUTHTYPE PAP, rejecting..."));
1343 if (!ao->neg_upap) { /* we don't want to do PAP */
1344 orc = CONFNAK; /* NAK it and suggest CHAP */
1345 PUTCHAR(CI_AUTHTYPE, nakp);
1346 PUTCHAR(CILEN_CHAP, nakp);
1347 PUTSHORT(PPP_CHAP, nakp);
1348 PUTCHAR(ao->chap_mdtype, nakp);
1354 if (cishort == PPP_CHAP) {
1355 if (ho->neg_upap || /* we've already accepted PAP */
1356 cilen != CILEN_CHAP) {
1357 LCPDEBUG(("lcp_reqci: rcvd AUTHTYPE CHAP, rejecting..."));
1361 if (!ao->neg_chap) { /* we don't want to do CHAP */
1362 orc = CONFNAK; /* NAK it and suggest PAP */
1363 PUTCHAR(CI_AUTHTYPE, nakp);
1364 PUTCHAR(CILEN_SHORT, nakp);
1365 PUTSHORT(PPP_PAP, nakp);
1368 GETCHAR(cichar, p); /* get digest type*/
1369 if (cichar != CHAP_DIGEST_MD5
1371 && cichar != CHAP_MICROSOFT
1375 PUTCHAR(CI_AUTHTYPE, nakp);
1376 PUTCHAR(CILEN_CHAP, nakp);
1377 PUTSHORT(PPP_CHAP, nakp);
1378 PUTCHAR(ao->chap_mdtype, nakp);
1381 ho->chap_mdtype = cichar; /* save md type */
1387 * We don't recognize the protocol they're asking for.
1388 * Nak it with something we're willing to do.
1389 * (At this point we know ao->neg_upap || ao->neg_chap.)
1392 PUTCHAR(CI_AUTHTYPE, nakp);
1394 PUTCHAR(CILEN_CHAP, nakp);
1395 PUTSHORT(PPP_CHAP, nakp);
1396 PUTCHAR(ao->chap_mdtype, nakp);
1398 PUTCHAR(CILEN_SHORT, nakp);
1399 PUTSHORT(PPP_PAP, nakp);
1405 cilen != CILEN_LQR) {
1410 GETSHORT(cishort, p);
1414 * Check the protocol and the reporting period.
1415 * XXX When should we Nak this, and what with?
1417 if (cishort != PPP_LQR) {
1419 PUTCHAR(CI_QUALITY, nakp);
1420 PUTCHAR(CILEN_LQR, nakp);
1421 PUTSHORT(PPP_LQR, nakp);
1422 PUTLONG(ao->lqr_period, nakp);
1427 case CI_MAGICNUMBER:
1428 if (!(ao->neg_magicnumber || go->neg_magicnumber) ||
1429 cilen != CILEN_LONG) {
1436 * He must have a different magic number.
1438 if (go->neg_magicnumber &&
1439 cilong == go->magicnumber) {
1440 cilong = magic(); /* Don't put magic() inside macro! */
1442 PUTCHAR(CI_MAGICNUMBER, nakp);
1443 PUTCHAR(CILEN_LONG, nakp);
1444 PUTLONG(cilong, nakp);
1447 ho->neg_magicnumber = 1;
1448 ho->magicnumber = cilong;
1452 case CI_PCOMPRESSION:
1453 if (!ao->neg_pcompression ||
1454 cilen != CILEN_VOID) {
1458 ho->neg_pcompression = 1;
1461 case CI_ACCOMPRESSION:
1462 if (!ao->neg_accompression ||
1463 cilen != CILEN_VOID) {
1467 ho->neg_accompression = 1;
1471 LCPDEBUG(("lcp_reqci: rcvd unknown option %d", citype));
1477 if (orc == CONFACK && /* Good CI */
1478 rc != CONFACK) /* but prior CI wasnt? */
1479 continue; /* Don't send this one */
1481 if (orc == CONFNAK) { /* Nak this CI? */
1482 if (reject_if_disagree /* Getting fed up with sending NAKs? */
1483 && citype != CI_MAGICNUMBER) {
1484 orc = CONFREJ; /* Get tough if so */
1486 if (rc == CONFREJ) /* Rejecting prior CI? */
1487 continue; /* Don't send this one */
1491 if (orc == CONFREJ) { /* Reject this CI */
1493 if (cip != rejp) /* Need to move rejected CI? */
1494 BCOPY(cip, rejp, cilen); /* Move it */
1495 INCPTR(cilen, rejp); /* Update output pointer */
1500 * If we wanted to send additional NAKs (for unsent CIs), the
1501 * code would go here. The extra NAKs would go at *nakp.
1502 * At present there are no cases where we want to ask the
1503 * peer to negotiate an option.
1512 * Copy the Nak'd options from the nak_buffer to the caller's buffer.
1514 *lenp = nakp - nak_buffer;
1515 BCOPY(nak_buffer, inp, *lenp);
1522 LCPDEBUG(("lcp_reqci: returning CONF%s.", CODENAME(rc)));
1523 return (rc); /* Return final code */
1528 * lcp_up - LCP has come UP.
1534 lcp_options *wo = &lcp_wantoptions[f->unit];
1535 lcp_options *ho = &lcp_hisoptions[f->unit];
1536 lcp_options *go = &lcp_gotoptions[f->unit];
1537 lcp_options *ao = &lcp_allowoptions[f->unit];
1539 if (!go->neg_magicnumber)
1540 go->magicnumber = 0;
1541 if (!ho->neg_magicnumber)
1542 ho->magicnumber = 0;
1545 * Set our MTU to the smaller of the MTU we wanted and
1546 * the MRU our peer wanted. If we negotiated an MRU,
1547 * set our MRU to the larger of value we wanted and
1548 * the value we got in the negotiation.
1550 ppp_send_config(f->unit, MIN(ao->mru, (ho->neg_mru? ho->mru: PPP_MRU)),
1551 (ho->neg_asyncmap? ho->asyncmap: 0xffffffff),
1552 ho->neg_pcompression, ho->neg_accompression);
1553 ppp_recv_config(f->unit, (go->neg_mru? MAX(wo->mru, go->mru): PPP_MRU),
1554 (go->neg_asyncmap? go->asyncmap: 0xffffffff),
1555 go->neg_pcompression, go->neg_accompression);
1558 peer_mru[f->unit] = ho->mru;
1560 lcp_echo_lowerup(f->unit); /* Enable echo messages */
1562 link_established(f->unit);
1567 * lcp_down - LCP has gone DOWN.
1569 * Alert other protocols.
1575 lcp_options *go = &lcp_gotoptions[f->unit];
1577 lcp_echo_lowerdown(f->unit);
1581 ppp_send_config(f->unit, PPP_MRU, 0xffffffff, 0, 0);
1582 ppp_recv_config(f->unit, PPP_MRU,
1583 (go->neg_asyncmap? go->asyncmap: 0xffffffff),
1584 go->neg_pcompression, go->neg_accompression);
1585 peer_mru[f->unit] = PPP_MRU;
1590 * lcp_starting - LCP needs the lower layer up.
1596 link_required(f->unit);
1601 * lcp_finished - LCP has finished with the lower layer.
1607 link_terminated(f->unit);
1612 * lcp_printpkt - print the contents of an LCP packet.
1614 static char *lcp_codenames[] = {
1615 "ConfReq", "ConfAck", "ConfNak", "ConfRej",
1616 "TermReq", "TermAck", "CodeRej", "ProtRej",
1617 "EchoReq", "EchoRep", "DiscReq"
1621 lcp_printpkt(p, plen, printer, arg)
1624 void (*printer) __P((void *, char *, ...));
1627 int code, id, len, olen;
1628 u_char *pstart, *optend;
1632 if (plen < HEADERLEN)
1638 if (len < HEADERLEN || len > plen)
1641 if (code >= 1 && code <= sizeof(lcp_codenames) / sizeof(char *))
1642 printer(arg, " %s", lcp_codenames[code-1]);
1644 printer(arg, " code=0x%x", code);
1645 printer(arg, " id=0x%x", id);
1652 /* print option list */
1657 if (olen < 2 || olen > len) {
1665 if (olen == CILEN_SHORT) {
1667 GETSHORT(cishort, p);
1668 printer(arg, "mru %d", cishort);
1672 if (olen == CILEN_LONG) {
1675 printer(arg, "asyncmap 0x%x", cilong);
1679 if (olen >= CILEN_SHORT) {
1681 printer(arg, "auth ");
1682 GETSHORT(cishort, p);
1685 printer(arg, "pap");
1688 printer(arg, "chap");
1691 case CHAP_DIGEST_MD5:
1692 printer(arg, " MD5");
1696 case CHAP_MICROSOFT:
1697 printer(arg, " m$oft");
1705 printer(arg, "0x%x", cishort);
1710 if (olen >= CILEN_SHORT) {
1712 printer(arg, "quality ");
1713 GETSHORT(cishort, p);
1716 printer(arg, "lqr");
1719 printer(arg, "0x%x", cishort);
1724 if (olen >= CILEN_CHAR) {
1726 printer(arg, "callback ");
1727 GETSHORT(cishort, p);
1730 printer(arg, "CBCP");
1733 printer(arg, "0x%x", cishort);
1737 case CI_MAGICNUMBER:
1738 if (olen == CILEN_LONG) {
1741 printer(arg, "magic 0x%x", cilong);
1744 case CI_PCOMPRESSION:
1745 if (olen == CILEN_VOID) {
1747 printer(arg, "pcomp");
1750 case CI_ACCOMPRESSION:
1751 if (olen == CILEN_VOID) {
1753 printer(arg, "accomp");
1757 while (p < optend) {
1759 printer(arg, " %.2x", code);
1767 if (len > 0 && *p >= ' ' && *p < 0x7f) {
1769 print_string(p, len, printer, arg);
1780 printer(arg, " magic=0x%x", cilong);
1787 /* print the rest of the bytes in the packet */
1788 for (; len > 0; --len) {
1790 printer(arg, " %.2x", code);
1797 * Time to shut down the link because there is nothing out there.
1801 void LcpLinkFailure (f)
1804 if (f->state == OPENED) {
1805 info("No response to %d echo-requests", lcp_echos_pending);
1806 notice("Serial link appears to be disconnected.");
1807 lcp_close(f->unit, "Peer not responding");
1812 * Timer expired for the LCP echo requests from this process.
1819 LcpSendEchoRequest (f);
1822 * Start the timer for the next interval.
1824 if (lcp_echo_timer_running)
1825 warn("assertion lcp_echo_timer_running==0 failed");
1826 TIMEOUT (LcpEchoTimeout, f, lcp_echo_interval);
1827 lcp_echo_timer_running = 1;
1831 * LcpEchoTimeout - Timer expired on the LCP echo
1835 LcpEchoTimeout (arg)
1838 if (lcp_echo_timer_running != 0) {
1839 lcp_echo_timer_running = 0;
1840 LcpEchoCheck ((fsm *) arg);
1845 * LcpEchoReply - LCP has received a reply to the echo
1849 lcp_received_echo_reply (f, id, inp, len)
1851 int id; u_char *inp; int len;
1855 /* Check the magic number - don't count replies from ourselves. */
1857 dbglog("lcp: received short Echo-Reply, length %d", len);
1860 GETLONG(magic, inp);
1861 if (lcp_gotoptions[f->unit].neg_magicnumber
1862 && magic == lcp_gotoptions[f->unit].magicnumber) {
1863 warn("appear to have received our own echo-reply!");
1867 /* Reset the number of outstanding echo frames */
1868 lcp_echos_pending = 0;
1872 * LcpSendEchoRequest - Send an echo request frame to the peer
1876 LcpSendEchoRequest (f)
1879 u_int32_t lcp_magic;
1880 u_char pkt[4], *pktp;
1883 * Detect the failure of the peer at this point.
1885 if (lcp_echo_fails != 0) {
1886 if (lcp_echos_pending >= lcp_echo_fails) {
1888 lcp_echos_pending = 0;
1893 * Make and send the echo request frame.
1895 if (f->state == OPENED) {
1896 lcp_magic = lcp_gotoptions[f->unit].magicnumber;
1898 PUTLONG(lcp_magic, pktp);
1899 fsm_sdata(f, ECHOREQ, lcp_echo_number++ & 0xFF, pkt, pktp - pkt);
1900 ++lcp_echos_pending;
1905 * lcp_echo_lowerup - Start the timer for the LCP frame
1909 lcp_echo_lowerup (unit)
1912 fsm *f = &lcp_fsm[unit];
1914 /* Clear the parameters for generating echo frames */
1915 lcp_echos_pending = 0;
1916 lcp_echo_number = 0;
1917 lcp_echo_timer_running = 0;
1919 /* If a timeout interval is specified then start the timer */
1920 if (lcp_echo_interval != 0)
1925 * lcp_echo_lowerdown - Stop the timer for the LCP frame
1929 lcp_echo_lowerdown (unit)
1932 fsm *f = &lcp_fsm[unit];
1934 if (lcp_echo_timer_running != 0) {
1935 UNTIMEOUT (LcpEchoTimeout, f);
1936 lcp_echo_timer_running = 0;