1 /*****************************************************************************
2 * ppp.c - Network Point to Point Protocol program file.
4 * Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
5 * portions Copyright (c) 1997 by Global Election Systems Inc.
7 * The authors hereby grant permission to use, copy, modify, distribute,
8 * and license this software and its documentation for any purpose, provided
9 * that existing copyright notices are retained in all copies and that this
10 * notice and the following disclaimer are included verbatim in any
11 * distributions. No written agreement, license, or royalty fee is required
12 * for any of the authorized uses.
14 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 ******************************************************************************
28 * 03-01-01 Marc Boucher <marc@mbsi.ca>
30 * 97-11-05 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
32 *****************************************************************************/
35 * ppp_defs.h - PPP definitions.
37 * if_pppvar.h - private structures and declarations for PPP.
39 * Copyright (c) 1994 The Australian National University.
40 * All rights reserved.
42 * Permission to use, copy, modify, and distribute this software and its
43 * documentation is hereby granted, provided that the above copyright
44 * notice appears in all copies. This software is provided without any
45 * warranty, express or implied. The Australian National University
46 * makes no representations about the suitability of this software for
49 * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
50 * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
51 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
52 * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
55 * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
56 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
57 * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
58 * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
59 * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
64 * if_ppp.h - Point-to-Point Protocol definitions.
66 * Copyright (c) 1989 Carnegie Mellon University.
67 * All rights reserved.
69 * Redistribution and use in source and binary forms are permitted
70 * provided that the above copyright notice and this paragraph are
71 * duplicated in all such forms and that any documentation,
72 * advertising materials, and other materials related to such
73 * distribution and use acknowledge that the software was developed
74 * by Carnegie Mellon University. The name of the
75 * University may not be used to endorse or promote products derived
76 * from this software without specific prior written permission.
77 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
78 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
79 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
101 /*************************/
102 /*** LOCAL DEFINITIONS ***/
103 /*************************/
106 * The basic PPP frame.
108 #define PPP_ADDRESS(p) (((u_char *)(p))[0])
109 #define PPP_CONTROL(p) (((u_char *)(p))[1])
110 #define PPP_PROTOCOL(p) ((((u_char *)(p))[2] << 8) + ((u_char *)(p))[3])
112 /* PPP packet parser states. Current state indicates operation yet to be
115 PDIDLE = 0, /* Idle state - waiting. */
116 PDSTART, /* Process start flag. */
117 PDADDRESS, /* Process address field. */
118 PDCONTROL, /* Process control field. */
119 PDPROTOCOL1, /* Process protocol field 1. */
120 PDPROTOCOL2, /* Process protocol field 2. */
121 PDDATA /* Process data byte. */
124 #define ESCAPE_P(accm, c) ((accm)[(c) >> 3] & pppACCMMask[c & 0x07])
126 /************************/
127 /*** LOCAL DATA TYPES ***/
128 /************************/
130 * PPP interface control block.
132 typedef struct PPPControl_s {
133 char openFlag; /* True when in use. */
134 char oldFrame; /* Old framing character for fd. */
135 sio_fd_t fd; /* File device ID of port. */
136 int kill_link; /* Shut the link down. */
137 int sig_hup; /* Carrier lost. */
138 int if_up; /* True when the interface is up. */
139 int errCode; /* Code indicating why interface is down. */
140 struct pbuf *inHead, *inTail; /* The input packet. */
141 PPPDevStates inState; /* The input process state. */
142 char inEscaped; /* Escape next character. */
143 u16_t inProtocol; /* The input protocol code. */
144 u16_t inFCS; /* Input Frame Check Sequence value. */
145 int mtu; /* Peer's mru */
146 int pcomp; /* Does peer accept protocol compression? */
147 int accomp; /* Does peer accept addr/ctl compression? */
148 u_long lastXMit; /* Time of last transmission. */
149 ext_accm inACCM; /* Async-Ctl-Char-Map for input. */
150 ext_accm outACCM; /* Async-Ctl-Char-Map for output. */
152 int vjEnabled; /* Flag indicating VJ compression enabled. */
153 struct vjcompress vjComp; /* Van Jabobsen compression header. */
158 struct ppp_addrs addrs;
160 void (*linkStatusCB)(void *ctx, int errCode, void *arg);
171 int protocol; /* PPP procotol, e.g. PPP_IP */
177 /***********************************/
178 /*** LOCAL FUNCTION DECLARATIONS ***/
179 /***********************************/
180 static void pppMain(void *pd);
181 static void pppDrop(PPPControl *pc);
182 static void pppInProc(int pd, u_char *s, int l);
185 /******************************/
186 /*** PUBLIC DATA STRUCTURES ***/
187 /******************************/
190 static PPPControl pppControl[NUM_PPP]; /* The PPP interface control blocks. */
193 * PPP Data Link Layer "protocol" table.
194 * One entry per supported protocol.
195 * The last entry must be NULL.
197 struct protent *ppp_protocols[] = {
217 * Buffers for outgoing packets. This must be accessed only from the appropriate
218 * PPP task so that it doesn't need to be protected to avoid collisions.
220 u_char outpacket_buf[NUM_PPP][PPP_MRU+PPP_HDRLEN];
223 /*****************************/
224 /*** LOCAL DATA STRUCTURES ***/
225 /*****************************/
228 * FCS lookup table as calculated by genfcstab.
230 static const u_short fcstab[256] = {
231 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
232 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
233 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
234 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
235 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
236 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
237 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
238 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
239 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
240 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
241 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
242 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
243 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
244 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
245 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
246 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
247 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
248 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
249 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
250 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
251 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
252 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
253 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
254 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
255 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
256 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
257 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
258 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
259 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
260 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
261 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
262 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
265 /* PPP's Asynchronous-Control-Character-Map. The mask array is used
266 * to select the specific bit for a character. */
267 static u_char pppACCMMask[] = {
279 /***********************************/
280 /*** PUBLIC FUNCTION DEFINITIONS ***/
281 /***********************************/
282 /* Initialize the PPP subsystem. */
284 struct ppp_settings ppp_settings;
288 struct protent *protp;
291 memset(&ppp_settings, 0, sizeof(ppp_settings));
292 ppp_settings.usepeerdns = 1;
293 pppSetAuth(PPPAUTHTYPE_NONE, NULL, NULL);
297 for (i = 0; i < NUM_PPP; i++) {
298 pppControl[i].openFlag = 0;
300 subnetMask = htonl(0xffffff00);
303 * Initialize to the standard option set.
305 for (j = 0; (protp = ppp_protocols[j]) != NULL; ++j)
310 /* Clear the statistics. */
311 memset(&lwip_stats.link, 0, sizeof(lwip_stats.link));
315 void pppSetAuth(enum pppAuthType authType, const char *user, const char *passwd)
318 case PPPAUTHTYPE_NONE:
320 #ifdef LWIP_PPP_STRICT_PAP_REJECT
321 ppp_settings.refuse_pap = 1;
323 /* some providers request pap and accept an empty login/pw */
324 ppp_settings.refuse_pap = 0;
326 ppp_settings.refuse_chap = 1;
328 case PPPAUTHTYPE_ANY:
329 /* Warning: Using PPPAUTHTYPE_ANY might have security consequences.
332 * In practice, within or associated with each PPP server, there is a
333 * database which associates "user" names with authentication
334 * information ("secrets"). It is not anticipated that a particular
335 * named user would be authenticated by multiple methods. This would
336 * make the user vulnerable to attacks which negotiate the least secure
337 * method from among a set (such as PAP rather than CHAP). If the same
338 * secret was used, PAP would reveal the secret to be used later with
341 * Instead, for each user name there should be an indication of exactly
342 * one method used to authenticate that user name. If a user needs to
343 * make use of different authentication methods under different
344 * circumstances, then distinct user names SHOULD be employed, each of
345 * which identifies exactly one authentication method.
348 ppp_settings.refuse_pap = 0;
349 ppp_settings.refuse_chap = 0;
351 case PPPAUTHTYPE_PAP:
352 ppp_settings.refuse_pap = 0;
353 ppp_settings.refuse_chap = 1;
355 case PPPAUTHTYPE_CHAP:
356 ppp_settings.refuse_pap = 1;
357 ppp_settings.refuse_chap = 0;
362 strncpy(ppp_settings.user, user, sizeof(ppp_settings.user)-1);
363 ppp_settings.user[sizeof(ppp_settings.user)-1] = '\0';
365 ppp_settings.user[0] = '\0';
368 strncpy(ppp_settings.passwd, passwd, sizeof(ppp_settings.passwd)-1);
369 ppp_settings.passwd[sizeof(ppp_settings.passwd)-1] = '\0';
371 ppp_settings.passwd[0] = '\0';
374 /* Open a new PPP connection using the given I/O device.
375 * This initializes the PPP control block but does not
376 * attempt to negotiate the LCP session. If this port
377 * connects to a modem, the modem connection must be
378 * established before calling this.
379 * Return a new PPP connection descriptor on success or
380 * an error code (negative) on failure. */
381 int pppOpen(sio_fd_t fd, void (*linkStatusCB)(void *ctx, int errCode, void *arg), void *linkStatusCtx)
386 /* Find a free PPP session descriptor. Critical region? */
387 for (pd = 0; pd < NUM_PPP && pppControl[pd].openFlag != 0; pd++);
391 pppControl[pd].openFlag = !0;
393 /* Launch a deamon thread. */
396 pppControl[pd].openFlag = 1;
399 pc = &pppControl[pd];
405 pc->inState = PDIDLE;
413 vj_compress_init(&pc->vjComp);
417 * Default the in and out accm so that escape and flag characters
418 * are always escaped.
420 memset(pc->inACCM, 0, sizeof(ext_accm));
421 pc->inACCM[15] = 0x60;
422 memset(pc->outACCM, 0, sizeof(ext_accm));
423 pc->outACCM[15] = 0x60;
425 pc->linkStatusCB = linkStatusCB;
426 pc->linkStatusCtx = linkStatusCtx;
428 sys_thread_new(pppMain, (void*)pd, PPP_THREAD_PRIO);
430 while(pd >= 0 && !pc->if_up) {
432 if (lcp_phase[pd] == PHASE_DEAD) {
445 /* Close a PPP connection and release the descriptor.
446 * Any outstanding packets in the queues are dropped.
447 * Return 0 on success, an error code on failure. */
450 PPPControl *pc = &pppControl[pd];
457 if(!pc->linkStatusCB) {
458 while(st >= 0 && lcp_phase[pd] != PHASE_DEAD) {
466 /* This function is called when carrier is lost on the PPP channel. */
467 void pppSigHUP(int pd)
469 PPPControl *pc = &pppControl[pd];
475 static void nPut(PPPControl *pc, struct pbuf *nb)
480 for(b = nb; b != NULL; b = b->next) {
481 if((c = sio_write(pc->fd, b->payload, b->len)) != b->len) {
482 PPPDEBUG((LOG_WARNING,
483 "PPP nPut: incomplete sio_write(%d,, %u) = %d\n", pc->fd, b->len, c));
485 lwip_stats.link.err++;
486 #endif /* LINK_STATS */
487 pc->lastXMit = 0; /* prepend PPP_FLAG to next packet */
494 lwip_stats.link.xmit++;
495 #endif /* LINK_STATS */
499 * pppAppend - append given character to end of given pbuf. If outACCM
500 * is not NULL and the character needs to be escaped, do so.
501 * If pbuf is full, append another.
502 * Return the current pbuf.
504 static struct pbuf *pppAppend(u_char c, struct pbuf *nb, ext_accm *outACCM)
506 struct pbuf *tb = nb;
508 /* Make sure there is room for the character and an escape code.
509 * Sure we don't quite fill the buffer if the character doesn't
510 * get escaped but is one character worth complicating this? */
511 /* Note: We assume no packet header. */
512 if (nb && (PBUF_POOL_BUFSIZE - nb->len) < 2) {
513 tb = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
519 lwip_stats.link.memerr++;
521 #endif /* LINK_STATS */
525 if (outACCM && ESCAPE_P(*outACCM, c)) {
526 *((u_char*)nb->payload + nb->len++) = PPP_ESCAPE;
527 *((u_char*)nb->payload + nb->len++) = c ^ PPP_TRANS;
530 *((u_char*)nb->payload + nb->len++) = c;
536 /* Send a packet on the given connection. */
537 static err_t pppifOutput(struct netif *netif, struct pbuf *pb, struct ip_addr *ipaddr)
539 int pd = (int)netif->state;
540 u_short protocol = PPP_IP;
541 PPPControl *pc = &pppControl[pd];
542 u_int fcsOut = PPP_INITFCS;
543 struct pbuf *headMB = NULL, *tailMB = NULL, *p;
548 /* Validate parameters. */
549 /* We let any protocol value go through - it can't hurt us
550 * and the peer will just drop it if it's not accepting it. */
551 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag || !pb) {
552 PPPDEBUG((LOG_WARNING, "pppifOutput[%d]: bad parms prot=%d pb=%p\n",
555 lwip_stats.link.opterr++;
556 lwip_stats.link.drop++;
561 /* Check that the link is up. */
562 if (lcp_phase[pd] == PHASE_DEAD) {
563 PPPDEBUG((LOG_ERR, "pppifOutput[%d]: link not up\n", pd));
565 lwip_stats.link.rterr++;
566 lwip_stats.link.drop++;
571 /* Grab an output buffer. */
572 headMB = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
573 if (headMB == NULL) {
574 PPPDEBUG((LOG_WARNING, "pppifOutput[%d]: first alloc fail\n", pd));
576 lwip_stats.link.memerr++;
577 lwip_stats.link.drop++;
578 #endif /* LINK_STATS */
584 * Attempt Van Jacobson header compression if VJ is configured and
585 * this is an IP packet.
587 if (protocol == PPP_IP && pc->vjEnabled) {
588 switch (vj_compress_tcp(&pc->vjComp, pb)) {
591 protocol = PPP_IP_PROTOCOL;
594 case TYPE_COMPRESSED_TCP:
595 protocol = PPP_VJC_COMP;
597 case TYPE_UNCOMPRESSED_TCP:
598 protocol = PPP_VJC_UNCOMP;
601 PPPDEBUG((LOG_WARNING, "pppifOutput[%d]: bad IP packet\n", pd));
603 lwip_stats.link.proterr++;
604 lwip_stats.link.drop++;
614 /* Build the PPP header. */
615 if ((sys_jiffies() - pc->lastXMit) >= PPP_MAXIDLEFLAG)
616 tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
617 pc->lastXMit = sys_jiffies();
619 fcsOut = PPP_FCS(fcsOut, PPP_ALLSTATIONS);
620 tailMB = pppAppend(PPP_ALLSTATIONS, tailMB, &pc->outACCM);
621 fcsOut = PPP_FCS(fcsOut, PPP_UI);
622 tailMB = pppAppend(PPP_UI, tailMB, &pc->outACCM);
624 if (!pc->pcomp || protocol > 0xFF) {
625 c = (protocol >> 8) & 0xFF;
626 fcsOut = PPP_FCS(fcsOut, c);
627 tailMB = pppAppend(c, tailMB, &pc->outACCM);
630 fcsOut = PPP_FCS(fcsOut, c);
631 tailMB = pppAppend(c, tailMB, &pc->outACCM);
634 for(p = pb; p; p = p->next) {
638 sPtr = (u_char*)p->payload;
643 /* Update FCS before checking for special characters. */
644 fcsOut = PPP_FCS(fcsOut, c);
646 /* Copy to output buffer escaping special characters. */
647 tailMB = pppAppend(c, tailMB, &pc->outACCM);
651 /* Add FCS and trailing flag. */
653 tailMB = pppAppend(c, tailMB, &pc->outACCM);
654 c = (~fcsOut >> 8) & 0xFF;
655 tailMB = pppAppend(c, tailMB, &pc->outACCM);
656 tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
658 /* If we failed to complete the packet, throw it away. */
660 PPPDEBUG((LOG_WARNING,
661 "pppifOutput[%d]: Alloc err - dropping proto=%d\n",
665 lwip_stats.link.memerr++;
666 lwip_stats.link.drop++;
672 PPPDEBUG((LOG_INFO, "pppifOutput[%d]: proto=0x%04X\n", pd, protocol));
679 /* Get and set parameters for the given connection.
680 * Return 0 on success, an error code on failure. */
681 int pppIOCtl(int pd, int cmd, void *arg)
683 PPPControl *pc = &pppControl[pd];
686 if (pd < 0 || pd >= NUM_PPP)
690 case PPPCTLG_UPSTATUS: /* Get the PPP up status. */
692 *(int *)arg = (int)(pc->if_up);
696 case PPPCTLS_ERRCODE: /* Set the PPP error code. */
698 pc->errCode = *(int *)arg;
702 case PPPCTLG_ERRCODE: /* Get the PPP error code. */
704 *(int *)arg = (int)(pc->errCode);
710 *(sio_fd_t *)arg = pc->fd;
724 * Return the Maximum Transmission Unit for the given PPP connection.
728 PPPControl *pc = &pppControl[pd];
731 /* Validate parameters. */
732 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag)
741 * Write n characters to a ppp link.
742 * RETURN: >= 0 Number of characters written
743 * -1 Failed to write to device
745 int pppWrite(int pd, const u_char *s, int n)
747 PPPControl *pc = &pppControl[pd];
749 u_int fcsOut = PPP_INITFCS;
750 struct pbuf *headMB = NULL, *tailMB;
751 headMB = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
752 if (headMB == NULL) {
754 lwip_stats.link.memerr++;
755 lwip_stats.link.proterr++;
756 #endif /* LINK_STATS */
762 /* If the link has been idle, we'll send a fresh flag character to
763 * flush any noise. */
764 if ((sys_jiffies() - pc->lastXMit) >= PPP_MAXIDLEFLAG)
765 tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
766 pc->lastXMit = sys_jiffies();
768 /* Load output buffer. */
772 /* Update FCS before checking for special characters. */
773 fcsOut = PPP_FCS(fcsOut, c);
775 /* Copy to output buffer escaping special characters. */
776 tailMB = pppAppend(c, tailMB, &pc->outACCM);
779 /* Add FCS and trailing flag. */
781 tailMB = pppAppend(c, tailMB, &pc->outACCM);
782 c = (~fcsOut >> 8) & 0xFF;
783 tailMB = pppAppend(c, tailMB, &pc->outACCM);
784 tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
786 /* If we failed to complete the packet, throw it away.
787 * Otherwise send it. */
789 PPPDEBUG((LOG_WARNING,
790 "pppWrite[%d]: Alloc err - dropping pbuf len=%d\n", pd, headMB->len));
791 /* "pppWrite[%d]: Alloc err - dropping %d:%.*H", pd, headMB->len, LWIP_MIN(headMB->len * 2, 40), headMB->payload)); */
794 lwip_stats.link.memerr++;
795 lwip_stats.link.proterr++;
796 #endif /* LINK_STATS */
800 PPPDEBUG((LOG_INFO, "pppWrite[%d]: len=%d\n", pd, headMB->len));
801 /* "pppWrite[%d]: %d:%.*H", pd, headMB->len, LWIP_MIN(headMB->len * 2, 40), headMB->payload)); */
808 * ppp_send_config - configure the transmit characteristics of
811 void ppp_send_config(
819 PPPControl *pc = &pppControl[unit];
826 /* Load the ACCM bits for the 32 control codes. */
827 for (i = 0; i < 32/8; i++)
828 pc->outACCM[i] = (u_char)((asyncmap >> (8 * i)) & 0xFF);
829 PPPDEBUG((LOG_INFO, "ppp_send_config[%d]: outACCM=%X %X %X %X\n",
831 pc->outACCM[0], pc->outACCM[1], pc->outACCM[2], pc->outACCM[3]));
836 * ppp_set_xaccm - set the extended transmit ACCM for the interface.
838 void ppp_set_xaccm(int unit, ext_accm *accm)
840 memcpy(pppControl[unit].outACCM, accm, sizeof(ext_accm));
841 PPPDEBUG((LOG_INFO, "ppp_set_xaccm[%d]: outACCM=%X %X %X %X\n",
843 pppControl[unit].outACCM[0],
844 pppControl[unit].outACCM[1],
845 pppControl[unit].outACCM[2],
846 pppControl[unit].outACCM[3]));
851 * ppp_recv_config - configure the receive-side characteristics of
854 void ppp_recv_config(
862 PPPControl *pc = &pppControl[unit];
869 /* Load the ACCM bits for the 32 control codes. */
870 for (i = 0; i < 32 / 8; i++)
871 pc->inACCM[i] = (u_char)(asyncmap >> (i * 8));
872 PPPDEBUG((LOG_INFO, "ppp_recv_config[%d]: inACCM=%X %X %X %X\n",
874 pc->inACCM[0], pc->inACCM[1], pc->inACCM[2], pc->inACCM[3]));
879 * ccp_test - ask kernel whether a given compression method
880 * is acceptable for use. Returns 1 if the method and parameters
881 * are OK, 0 if the method is known but the parameters are not OK
882 * (e.g. code size should be reduced), or -1 if the method is unknown.
891 return 0; /* XXX Currently no compression. */
895 * ccp_flags_set - inform kernel about the current state of CCP.
897 void ccp_flags_set(int unit, int isopen, int isup)
903 * ccp_fatal_error - returns 1 if decompression was disabled as a
904 * result of an error detected after decompression of a packet,
905 * 0 otherwise. This is necessary because of patent nonsense.
907 int ccp_fatal_error(int unit)
915 * get_idle_time - return how long the link has been idle.
917 int get_idle_time(int u, struct ppp_idle *ip)
928 * Return user specified netmask, modified by any mask we might determine
929 * for address `addr' (in network byte order).
930 * Here we scan through the system's list of interfaces, looking for
931 * any non-point-to-point interfaces which might appear to be on the same
932 * network as `addr'. If we find any, we OR in their netmask to the
933 * user-specified netmask.
935 u32_t GetMask(u32_t addr)
940 if (IN_CLASSA(addr)) /* determine network mask for address class */
941 nmask = IN_CLASSA_NET;
942 else if (IN_CLASSB(addr))
943 nmask = IN_CLASSB_NET;
945 nmask = IN_CLASSC_NET;
946 /* class D nets are disallowed by bad_ip_adrs */
947 mask = subnetMask | htonl(nmask);
950 * Scan through the system's network interfaces.
951 * Get each netmask and OR them into our mask.
958 * sifvjcomp - config tcp header compression
968 PPPControl *pc = &pppControl[pd];
970 pc->vjEnabled = vjcomp;
971 pc->vjComp.compressSlot = cidcomp;
972 pc->vjComp.maxSlotIndex = maxcid;
973 PPPDEBUG((LOG_INFO, "sifvjcomp: VJ compress enable=%d slot=%d max slot=%d\n",
974 vjcomp, cidcomp, maxcid));
981 * pppifNetifInit - netif init callback
983 static err_t pppifNetifInit(struct netif *netif)
985 netif->name[0] = 'p';
986 netif->name[1] = 'p';
987 netif->output = pppifOutput;
988 netif->mtu = pppMTU((int)netif->state);
994 * sifup - Config the interface up and enable IP packets to pass.
998 PPPControl *pc = &pppControl[pd];
1001 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
1003 PPPDEBUG((LOG_WARNING, "sifup[%d]: bad parms\n", pd));
1005 netif_remove(&pc->netif);
1006 if (netif_add(&pc->netif, &pc->addrs.our_ipaddr, &pc->addrs.netmask, &pc->addrs.his_ipaddr, (void *)pd, pppifNetifInit, ip_input)) {
1008 pc->errCode = PPPERR_NONE;
1010 PPPDEBUG((LOG_DEBUG, "sifup: unit %d: linkStatusCB=%lx errCode=%d\n", pd, pc->linkStatusCB, pc->errCode));
1011 if(pc->linkStatusCB)
1012 pc->linkStatusCB(pc->linkStatusCtx, pc->errCode, &pc->addrs);
1015 PPPDEBUG((LOG_ERR, "sifup[%d]: netif_add failed\n", pd));
1023 * sifnpmode - Set the mode for handling packets for a given NP.
1025 int sifnpmode(int u, int proto, enum NPmode mode)
1034 * sifdown - Config the interface down and disable IP.
1038 PPPControl *pc = &pppControl[pd];
1041 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
1043 PPPDEBUG((LOG_WARNING, "sifdown[%d]: bad parms\n", pd));
1046 netif_remove(&pc->netif);
1047 PPPDEBUG((LOG_DEBUG, "sifdown: unit %d: linkStatusCB=%lx errCode=%d\n", pd, pc->linkStatusCB, pc->errCode));
1048 if(pc->linkStatusCB)
1049 pc->linkStatusCB(pc->linkStatusCtx, PPPERR_CONNECT, NULL);
1055 * sifaddr - Config the interface IP addresses and netmask.
1058 int pd, /* Interface unit ??? */
1059 u32_t o, /* Our IP address ??? */
1060 u32_t h, /* His IP address ??? */
1061 u32_t m, /* IP subnet mask ??? */
1062 u32_t ns1, /* Primary DNS */
1063 u32_t ns2 /* Secondary DNS */
1066 PPPControl *pc = &pppControl[pd];
1069 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
1071 PPPDEBUG((LOG_WARNING, "sifup[%d]: bad parms\n", pd));
1073 memcpy(&pc->addrs.our_ipaddr, &o, sizeof(o));
1074 memcpy(&pc->addrs.his_ipaddr, &h, sizeof(h));
1075 memcpy(&pc->addrs.netmask, &m, sizeof(m));
1076 memcpy(&pc->addrs.dns1, &ns1, sizeof(ns1));
1077 memcpy(&pc->addrs.dns2, &ns2, sizeof(ns2));
1083 * cifaddr - Clear the interface IP addresses, and delete routes
1084 * through the interface if possible.
1087 int pd, /* Interface unit ??? */
1088 u32_t o, /* Our IP address ??? */
1089 u32_t h /* IP broadcast address ??? */
1092 PPPControl *pc = &pppControl[pd];
1097 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
1099 PPPDEBUG((LOG_WARNING, "sifup[%d]: bad parms\n", pd));
1101 IP4_ADDR(&pc->addrs.our_ipaddr, 0,0,0,0);
1102 IP4_ADDR(&pc->addrs.his_ipaddr, 0,0,0,0);
1103 IP4_ADDR(&pc->addrs.netmask, 255,255,255,0);
1104 IP4_ADDR(&pc->addrs.dns1, 0,0,0,0);
1105 IP4_ADDR(&pc->addrs.dns2, 0,0,0,0);
1111 * sifdefaultroute - assign a default route through the address given.
1113 int sifdefaultroute(int pd, u32_t l, u32_t g)
1115 PPPControl *pc = &pppControl[pd];
1120 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
1122 PPPDEBUG((LOG_WARNING, "sifup[%d]: bad parms\n", pd));
1124 netif_set_default(&pc->netif);
1127 /* TODO: check how PPP handled the netMask, previously not set by ipSetDefault */
1133 * cifdefaultroute - delete a default route through the address given.
1135 int cifdefaultroute(int pd, u32_t l, u32_t g)
1137 PPPControl *pc = &pppControl[pd];
1142 if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
1144 PPPDEBUG((LOG_WARNING, "sifup[%d]: bad parms\n", pd));
1146 netif_set_default(NULL);
1153 pppMainWakeup(int pd)
1155 PPPDEBUG((LOG_DEBUG, "pppMainWakeup: unit %d\n", pd));
1156 sio_read_abort(pppControl[pd].fd);
1159 /* these callbacks are necessary because lcp_* functions
1160 must be called in the same context as pppInput(),
1161 namely the tcpip_thread(), essentially because
1162 they manipulate timeouts which are thread-private
1166 pppStartCB(void *arg)
1170 PPPDEBUG((LOG_DEBUG, "pppStartCB: unit %d\n", pd));
1172 lcp_open(pd); /* Start protocol */
1176 pppStopCB(void *arg)
1180 PPPDEBUG((LOG_DEBUG, "pppStopCB: unit %d\n", pd));
1181 lcp_close(pd, "User request");
1189 PPPDEBUG((LOG_DEBUG, "pppHupCB: unit %d\n", pd));
1191 link_terminated(pd);
1193 /**********************************/
1194 /*** LOCAL FUNCTION DEFINITIONS ***/
1195 /**********************************/
1196 /* The main PPP process function. This implements the state machine according
1197 * to section 4 of RFC 1661: The Point-To-Point Protocol. */
1198 static void pppMain(void *arg)
1204 pc = &pppControl[pd];
1206 p = pbuf_alloc(PBUF_RAW, PPP_MRU+PPP_HDRLEN, PBUF_RAM);
1208 LWIP_ASSERT("p != NULL", p);
1209 pc->errCode = PPPERR_ALLOC;
1214 * Start the connection and handle incoming events (packet or timeout).
1216 PPPDEBUG((LOG_INFO, "pppMain: unit %d: Connecting\n", pd));
1217 tcpip_callback(pppStartCB, arg);
1218 while (lcp_phase[pd] != PHASE_DEAD) {
1219 if (pc->kill_link) {
1220 PPPDEBUG((LOG_DEBUG, "pppMainWakeup: unit %d kill_link -> pppStopCB\n", pd));
1221 pc->errCode = PPPERR_USER;
1222 /* This will leave us at PHASE_DEAD. */
1223 tcpip_callback(pppStopCB, arg);
1226 else if (pc->sig_hup) {
1227 PPPDEBUG((LOG_DEBUG, "pppMainWakeup: unit %d sig_hup -> pppHupCB\n", pd));
1229 tcpip_callback(pppHupCB, arg);
1231 int c = sio_read(pc->fd, p->payload, p->len);
1233 pppInProc(pd, p->payload, c);
1235 PPPDEBUG((LOG_DEBUG, "pppMainWakeup: unit %d sio_read len=%d returned %d\n", pd, p->len, c));
1236 sys_msleep(1); /* give other tasks a chance to run */
1240 PPPDEBUG((LOG_INFO, "pppMain: unit %d: PHASE_DEAD\n", pd));
1244 PPPDEBUG((LOG_DEBUG, "pppMain: unit %d: linkStatusCB=%lx errCode=%d\n", pd, pc->linkStatusCB, pc->errCode));
1245 if(pc->linkStatusCB)
1246 pc->linkStatusCB(pc->linkStatusCtx, pc->errCode ? pc->errCode : PPPERR_PROTOCOL, NULL);
1251 static struct pbuf *pppSingleBuf(struct pbuf *p)
1256 if(p->tot_len == p->len)
1259 q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
1262 "pppSingleBuf: unable to alloc new buf (%d)\n", p->tot_len));
1263 return p; /* live dangerously */
1266 for(b = p, pl = q->payload; b != NULL; b = b->next) {
1267 memcpy(pl, b->payload, b->len);
1276 struct pppInputHeader {
1282 * Pass the processed input packet to the appropriate handler.
1283 * This function and all handlers run in the context of the tcpip_thread
1285 static void pppInput(void *arg)
1287 struct pbuf *nb = (struct pbuf *)arg;
1291 pd = ((struct pppInputHeader *)nb->payload)->unit;
1292 protocol = ((struct pppInputHeader *)nb->payload)->proto;
1294 pbuf_header(nb, -(int)sizeof(struct pppInputHeader));
1297 lwip_stats.link.recv++;
1298 #endif /* LINK_STATS */
1301 * Toss all non-LCP packets unless LCP is OPEN.
1302 * Until we get past the authentication phase, toss all packets
1303 * except LCP, LQR and authentication packets.
1305 if((lcp_phase[pd] <= PHASE_AUTHENTICATE) && (protocol != PPP_LCP)) {
1306 if(!((protocol == PPP_LQR) || (protocol == PPP_PAP) || (protocol == PPP_CHAP)) ||
1307 (lcp_phase[pd] != PHASE_AUTHENTICATE)) {
1308 PPPDEBUG((LOG_INFO, "pppInput: discarding proto 0x%04X in phase %d\n", protocol, lcp_phase[pd]));
1314 case PPP_VJC_COMP: /* VJ compressed TCP */
1316 PPPDEBUG((LOG_INFO, "pppInput[%d]: vj_comp in pbuf len=%d\n", pd, nb->len));
1318 * Clip off the VJ header and prepend the rebuilt TCP/IP header and
1319 * pass the result to IP.
1321 if (vj_uncompress_tcp(&nb, &pppControl[pd].vjComp) >= 0) {
1322 pppControl[pd].netif.input(nb, &pppControl[pd].netif);
1325 /* Something's wrong so drop it. */
1326 PPPDEBUG((LOG_WARNING, "pppInput[%d]: Dropping VJ compressed\n", pd));
1328 /* No handler for this protocol so drop the packet. */
1329 PPPDEBUG((LOG_INFO, "pppInput[%d]: drop VJ Comp in %d:%s\n", pd, nb->len, nb->payload));
1330 #endif /* VJ_SUPPORT > 0 */
1332 case PPP_VJC_UNCOMP: /* VJ uncompressed TCP */
1334 PPPDEBUG((LOG_INFO, "pppInput[%d]: vj_un in pbuf len=%d\n", pd, nb->len));
1336 * Process the TCP/IP header for VJ header compression and then pass
1339 if (vj_uncompress_uncomp(nb, &pppControl[pd].vjComp) >= 0) {
1340 pppControl[pd].netif.input(nb, &pppControl[pd].netif);
1343 /* Something's wrong so drop it. */
1344 PPPDEBUG((LOG_WARNING, "pppInput[%d]: Dropping VJ uncompressed\n", pd));
1346 /* No handler for this protocol so drop the packet. */
1348 "pppInput[%d]: drop VJ UnComp in %d:.*H\n",
1349 pd, nb->len, LWIP_MIN(nb->len * 2, 40), nb->payload));
1350 #endif /* VJ_SUPPORT > 0 */
1352 case PPP_IP: /* Internet Protocol */
1353 PPPDEBUG((LOG_INFO, "pppInput[%d]: ip in pbuf len=%d\n", pd, nb->len));
1354 pppControl[pd].netif.input(nb, &pppControl[pd].netif);
1358 struct protent *protp;
1362 * Upcall the proper protocol input routine.
1364 for (i = 0; (protp = ppp_protocols[i]) != NULL; ++i) {
1365 if (protp->protocol == protocol && protp->enabled_flag) {
1366 PPPDEBUG((LOG_INFO, "pppInput[%d]: %s len=%d\n", pd, protp->name, nb->len));
1367 nb = pppSingleBuf(nb);
1368 (*protp->input)(pd, nb->payload, nb->len);
1373 /* No handler for this protocol so reject the packet. */
1374 PPPDEBUG((LOG_INFO, "pppInput[%d]: rejecting unsupported proto 0x%04X len=%d\n", pd, protocol, nb->len));
1375 pbuf_header(nb, sizeof(protocol));
1376 #if BYTE_ORDER == LITTLE_ENDIAN
1377 protocol = htons(protocol);
1378 memcpy(nb->payload, &protocol, sizeof(protocol));
1380 lcp_sprotrej(pd, nb->payload, nb->len);
1387 lwip_stats.link.drop++;
1397 * Drop the input packet.
1399 static void pppDrop(PPPControl *pc)
1401 if (pc->inHead != NULL) {
1403 PPPDEBUG((LOG_INFO, "pppDrop: %d:%.*H\n", pc->inHead->len, min(60, pc->inHead->len * 2), pc->inHead->payload));
1405 PPPDEBUG((LOG_INFO, "pppDrop: pbuf len=%d\n", pc->inHead->len));
1406 if (pc->inTail && (pc->inTail != pc->inHead))
1407 pbuf_free(pc->inTail);
1408 pbuf_free(pc->inHead);
1413 vj_uncompress_err(&pc->vjComp);
1417 lwip_stats.link.drop++;
1418 #endif /* LINK_STATS */
1423 * Process a received octet string.
1425 static void pppInProc(int pd, u_char *s, int l)
1427 PPPControl *pc = &pppControl[pd];
1428 struct pbuf *nextNBuf;
1431 PPPDEBUG((LOG_DEBUG, "pppInProc[%d]: got %d bytes\n", pd, l));
1435 /* Handle special characters. */
1436 if (ESCAPE_P(pc->inACCM, curChar)) {
1437 /* Check for escape sequences. */
1438 /* XXX Note that this does not handle an escaped 0x5d character which
1439 * would appear as an escape character. Since this is an ASCII ']'
1440 * and there is no reason that I know of to escape it, I won't complicate
1441 * the code to handle this case. GLL */
1442 if (curChar == PPP_ESCAPE)
1444 /* Check for the flag character. */
1445 else if (curChar == PPP_FLAG) {
1446 /* If this is just an extra flag character, ignore it. */
1447 if (pc->inState <= PDADDRESS)
1449 /* If we haven't received the packet header, drop what has come in. */
1450 else if (pc->inState < PDDATA) {
1451 PPPDEBUG((LOG_WARNING,
1452 "pppInProc[%d]: Dropping incomplete packet %d\n",
1455 lwip_stats.link.lenerr++;
1459 /* If the fcs is invalid, drop the packet. */
1460 else if (pc->inFCS != PPP_GOODFCS) {
1462 "pppInProc[%d]: Dropping bad fcs 0x%04X proto=0x%04X\n",
1463 pd, pc->inFCS, pc->inProtocol));
1465 lwip_stats.link.chkerr++;
1469 /* Otherwise it's a good packet so pass it on. */
1472 /* Trim off the checksum. */
1473 if(pc->inTail->len >= 2) {
1474 pc->inTail->len -= 2;
1476 pc->inTail->tot_len = pc->inTail->len;
1477 if (pc->inTail != pc->inHead) {
1478 pbuf_cat(pc->inHead, pc->inTail);
1481 pc->inTail->tot_len = pc->inTail->len;
1482 if (pc->inTail != pc->inHead) {
1483 pbuf_cat(pc->inHead, pc->inTail);
1486 pbuf_realloc(pc->inHead, pc->inHead->tot_len - 2);
1489 /* Dispatch the packet thereby consuming it. */
1490 if(tcpip_callback(pppInput, pc->inHead) != ERR_OK) {
1492 "pppInProc[%d]: tcpip_callback() failed, dropping packet\n", pd));
1493 pbuf_free(pc->inHead);
1495 lwip_stats.link.drop++;
1502 /* Prepare for a new packet. */
1503 pc->inFCS = PPP_INITFCS;
1504 pc->inState = PDADDRESS;
1507 /* Other characters are usually control characters that may have
1508 * been inserted by the physical layer so here we just drop them. */
1510 PPPDEBUG((LOG_WARNING,
1511 "pppInProc[%d]: Dropping ACCM char <%d>\n", pd, curChar));
1514 /* Process other characters. */
1516 /* Unencode escaped characters. */
1517 if (pc->inEscaped) {
1519 curChar ^= PPP_TRANS;
1522 /* Process character relative to current state. */
1523 switch(pc->inState) {
1524 case PDIDLE: /* Idle state - waiting. */
1525 /* Drop the character if it's not 0xff
1526 * we would have processed a flag character above. */
1527 if (curChar != PPP_ALLSTATIONS) {
1532 case PDSTART: /* Process start flag. */
1533 /* Prepare for a new packet. */
1534 pc->inFCS = PPP_INITFCS;
1537 case PDADDRESS: /* Process address field. */
1538 if (curChar == PPP_ALLSTATIONS) {
1539 pc->inState = PDCONTROL;
1542 /* Else assume compressed address and control fields so
1543 * fall through to get the protocol... */
1544 case PDCONTROL: /* Process control field. */
1545 /* If we don't get a valid control code, restart. */
1546 if (curChar == PPP_UI) {
1547 pc->inState = PDPROTOCOL1;
1552 PPPDEBUG((LOG_WARNING,
1553 "pppInProc[%d]: Invalid control <%d>\n", pd, curChar));
1554 pc->inState = PDSTART;
1557 case PDPROTOCOL1: /* Process protocol field 1. */
1558 /* If the lower bit is set, this is the end of the protocol
1561 pc->inProtocol = curChar;
1562 pc->inState = PDDATA;
1565 pc->inProtocol = (u_int)curChar << 8;
1566 pc->inState = PDPROTOCOL2;
1569 case PDPROTOCOL2: /* Process protocol field 2. */
1570 pc->inProtocol |= curChar;
1571 pc->inState = PDDATA;
1573 case PDDATA: /* Process data byte. */
1574 /* Make space to receive processed data. */
1575 if (pc->inTail == NULL || pc->inTail->len == PBUF_POOL_BUFSIZE) {
1577 pc->inTail->tot_len = pc->inTail->len;
1578 if (pc->inTail != pc->inHead) {
1579 pbuf_cat(pc->inHead, pc->inTail);
1582 /* If we haven't started a packet, we need a packet header. */
1583 nextNBuf = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
1584 if (nextNBuf == NULL) {
1585 /* No free buffers. Drop the input packet and let the
1586 * higher layers deal with it. Continue processing
1587 * the received pbuf chain in case a new packet starts. */
1588 PPPDEBUG((LOG_ERR, "pppInProc[%d]: NO FREE MBUFS!\n", pd));
1590 lwip_stats.link.memerr++;
1591 #endif /* LINK_STATS */
1593 pc->inState = PDSTART; /* Wait for flag sequence. */
1596 if (pc->inHead == NULL) {
1597 struct pppInputHeader *pih = nextNBuf->payload;
1600 pih->proto = pc->inProtocol;
1602 nextNBuf->len += sizeof(*pih);
1604 pc->inHead = nextNBuf;
1606 pc->inTail = nextNBuf;
1608 /* Load character into buffer. */
1609 ((u_char*)pc->inTail->payload)[pc->inTail->len++] = curChar;
1613 /* update the frame check sequence number. */
1614 pc->inFCS = PPP_FCS(pc->inFCS, curChar);
1620 #endif /* PPP_SUPPORT */