-/*
- * ppp_ahdlc.c - STREAMS module for doing PPP asynchronous HDLC.
- *
- * Copyright (c) 1994 The Australian National University.
- * All rights reserved.
- *
- * Permission to use, copy, modify, and distribute this software and its
- * documentation is hereby granted, provided that the above copyright
- * notice appears in all copies. This software is provided without any
- * warranty, express or implied. The Australian National University
- * makes no representations about the suitability of this software for
- * any purpose.
- *
- * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
- * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
- * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
- * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
- * OF SUCH DAMAGE.
- *
- * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
- * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
- * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
- * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
- * OR MODIFICATIONS.
- *
- * $Id: ppp_ahdlc.c,v 1.5 1995/10/27 03:57:10 paulus Exp $
- */
-
-/*
- * This file is used under Solaris 2.
- */
-
-#include <sys/types.h>
-#include <sys/param.h>
-#include <sys/stream.h>
-#include <sys/conf.h>
-#include <sys/kmem.h>
-#include <sys/errno.h>
-#include <sys/cmn_err.h>
-#include <sys/ddi.h>
-#ifdef sun
-#include <sys/modctl.h>
-#include <sys/sunddi.h>
-#endif
-#include <net/ppp_defs.h>
-#include <net/pppio.h>
-
-#define IFRAME_BSIZE 512 /* Block size to allocate for input */
-#define OFRAME_BSIZE 4096 /* Don't allocb more than this for output */
-
-static int ahdlc_open __P((queue_t *, dev_t *, int, int, cred_t *));
-static int ahdlc_close __P((queue_t *, int, cred_t *));
-static int ahdlc_wput __P((queue_t *, mblk_t *));
-static int ahdlc_rput __P((queue_t *, mblk_t *));
-static void stuff_frame __P((queue_t *, mblk_t *));
-static void unstuff_chars __P((queue_t *, mblk_t *));
-static int msg_copy __P((uchar_t *, mblk_t *, int));
-
-static struct module_info minfo = {
- 0x7d23, "ppp_ahdl", 0, INFPSZ, 4096, 128
-};
-
-static struct qinit rinit = {
- ahdlc_rput, NULL, ahdlc_open, ahdlc_close, NULL, &minfo, NULL
-};
-
-static struct qinit winit = {
- ahdlc_wput, NULL, NULL, NULL, NULL, &minfo, NULL
-};
-
-static struct streamtab ahdlc_info = {
- &rinit, &winit, NULL, NULL
-};
-
-#ifdef sun
-static struct fmodsw fsw = {
- "ppp_ahdl",
- &ahdlc_info,
- D_NEW | D_MP | D_MTQPAIR
-};
-
-extern struct mod_ops mod_strmodops;
-
-static struct modlstrmod modlstrmod = {
- &mod_strmodops,
- "PPP async HDLC module",
- &fsw
-};
-
-static struct modlinkage modlinkage = {
- MODREV_1,
- (void *) &modlstrmod,
- NULL
-};
-#endif /* sun */
-
-typedef struct ahdlc_state {
- int flags;
- mblk_t *cur_frame;
- mblk_t *cur_blk;
- int inlen;
- ushort infcs;
- u_int32_t xaccm[8];
- u_int32_t raccm;
- int mtu;
- int mru;
- int unit;
- struct pppstat stats;
-} ahdlc_state_t;
-
-/* Values for flags */
-#define ESCAPED 0x100 /* last saw escape char on input */
-#define IFLUSH 0x200 /* flushing input due to error */
-
-/* RCV_B7_1, etc., defined in net/pppio.h, are stored in flags also. */
-#define RCV_FLAGS (RCV_B7_1|RCV_B7_0|RCV_ODDP|RCV_EVNP)
-
-#ifndef sun
-# define qprocson(q)
-# define qprocsoff(q)
-#endif
-
-/*
- * FCS lookup table as calculated by genfcstab.
- */
-static u_short fcstab[256] = {
- 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
- 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
- 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
- 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
- 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
- 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
- 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
- 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
- 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
- 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
- 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
- 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
- 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
- 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
- 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
- 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
- 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
- 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
- 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
- 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
- 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
- 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
- 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
- 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
- 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
- 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
- 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
- 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
- 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
- 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
- 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
- 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
-};
-
-#ifdef sun
-/*
- * Entry points for modloading.
- */
-int
-_init(void)
-{
- return mod_install(&modlinkage);
-}
-
-int
-_fini(void)
-{
- return mod_remove(&modlinkage);
-}
-
-int
-_info(mip)
- struct modinfo *mip;
-{
- return mod_info(&modlinkage, mip);
-}
-#endif
-
-/*
- * STREAMS module entry points.
- */
-static int
-ahdlc_open(q, devp, flag, sflag, credp)
- queue_t *q;
- dev_t *devp;
- int flag, sflag;
- cred_t *credp;
-{
- ahdlc_state_t *sp;
-
- if (q->q_ptr == 0) {
- sp = (ahdlc_state_t *) kmem_zalloc(sizeof(ahdlc_state_t), KM_SLEEP);
- if (sp == 0)
- return ENOSR;
- q->q_ptr = sp;
- WR(q)->q_ptr = sp;
- sp->xaccm[0] = ~0;
- sp->xaccm[3] = 0x60000000;
- sp->mru = 1500;
- qprocson(q);
- }
- return 0;
-}
-
-static int
-ahdlc_close(q, flag, credp)
- queue_t *q;
- int flag;
- cred_t *credp;
-{
- ahdlc_state_t *state;
-
- qprocsoff(q);
- if (q->q_ptr != 0) {
- state = (ahdlc_state_t *) q->q_ptr;
- if (state->cur_frame != 0) {
- freemsg(state->cur_frame);
- state->cur_frame = 0;
- }
- kmem_free(q->q_ptr, sizeof(ahdlc_state_t));
- }
- return 0;
-}
-
-static int
-ahdlc_wput(q, mp)
- queue_t *q;
- mblk_t *mp;
-{
- ahdlc_state_t *state;
- struct iocblk *iop;
- int error;
- mblk_t *np;
- struct ppp_stats *psp;
-
- state = (ahdlc_state_t *) q->q_ptr;
- switch (mp->b_datap->db_type) {
- case M_DATA:
- /*
- * A data packet - do character-stuffing and FCS, and
- * send it onwards.
- */
- stuff_frame(q, mp);
- freemsg(mp);
- break;
-
- case M_IOCTL:
- iop = (struct iocblk *) mp->b_rptr;
- error = EINVAL;
- switch (iop->ioc_cmd) {
- case PPPIO_XACCM:
- if (iop->ioc_count < sizeof(u_int32_t)
- || iop->ioc_count > sizeof(ext_accm))
- break;
- bcopy(mp->b_cont->b_rptr, (caddr_t)state->xaccm, iop->ioc_count);
- state->xaccm[2] &= 0x40000000; /* don't escape 0x5e */
- state->xaccm[3] |= 0x60000000; /* do escape 0x7d, 0x7e */
- iop->ioc_count = 0;
- error = 0;
- break;
-
- case PPPIO_RACCM:
- if (iop->ioc_count != sizeof(u_int32_t))
- break;
- bcopy(mp->b_cont->b_rptr, (caddr_t)&state->raccm,
- sizeof(u_int32_t));
- iop->ioc_count = 0;
- error = 0;
- break;
-
- case PPPIO_GCLEAN:
- np = allocb(sizeof(int), BPRI_HI);
- if (np == 0) {
- error = ENOSR;
- break;
- }
- if (mp->b_cont != 0)
- freemsg(mp->b_cont);
- mp->b_cont = np;
- *(int *)np->b_wptr = state->flags & RCV_FLAGS;
- np->b_wptr += sizeof(int);
- iop->ioc_count = sizeof(int);
- error = 0;
- break;
-
- case PPPIO_GETSTAT:
- np = allocb(sizeof(struct ppp_stats), BPRI_HI);
- if (np == 0) {
- error = ENOSR;
- break;
- }
- if (mp->b_cont != 0)
- freemsg(mp->b_cont);
- mp->b_cont = np;
- psp = (struct ppp_stats *) np->b_wptr;
- np->b_wptr += sizeof(struct ppp_stats);
- bzero((caddr_t)psp, sizeof(struct ppp_stats));
- psp->p = state->stats;
- iop->ioc_count = sizeof(struct ppp_stats);
- error = 0;
- break;
-
- case PPPIO_LASTMOD:
- /* we knew this anyway */
- error = 0;
- break;
-
- default:
- error = -1;
- break;
- }
-
- if (error < 0)
- putnext(q, mp);
- else if (error == 0) {
- mp->b_datap->db_type = M_IOCACK;
- qreply(q, mp);
- } else {
- mp->b_datap->db_type = M_IOCNAK;
- iop->ioc_count = 0;
- iop->ioc_error = error;
- qreply(q, mp);
- }
- break;
-
- case M_CTL:
- switch (*mp->b_rptr) {
- case PPPCTL_MTU:
- state->mtu = ((unsigned short *)mp->b_rptr)[1];
- freemsg(mp);
- break;
- case PPPCTL_MRU:
- state->mru = ((unsigned short *)mp->b_rptr)[1];
- freemsg(mp);
- break;
- case PPPCTL_UNIT:
- state->unit = mp->b_rptr[1];
- break;
- default:
- putnext(q, mp);
- }
- break;
-
- default:
- putnext(q, mp);
- }
- return 0;
-}
-
-static int
-ahdlc_rput(q, mp)
- queue_t *q;
- mblk_t *mp;
-{
- mblk_t *np;
- uchar_t *cp;
- ahdlc_state_t *state;
-
- switch (mp->b_datap->db_type) {
- case M_DATA:
- unstuff_chars(q, mp);
- freemsg(mp);
- break;
-
- case M_HANGUP:
- state = (ahdlc_state_t *) q->q_ptr;
- if (state->cur_frame != 0) {
- /* XXX would like to send this up for debugging */
- freemsg(state->cur_frame);
- state->cur_frame = 0;
- state->cur_blk = 0;
- }
- state->inlen = 0;
- state->flags = IFLUSH;
- putnext(q, mp);
- break;
-
- default:
- putnext(q, mp);
- }
- return 0;
-}
-
-/* Extract bit c from map m, to determine if c needs to be escaped. */
-#define ESCAPE(c, m) ((m)[(c) >> 5] & (1 << ((c) & 0x1f)))
-
-static void
-stuff_frame(q, mp)
- queue_t *q;
- mblk_t *mp;
-{
- ahdlc_state_t *state;
- int ilen, olen, c, extra, i;
- mblk_t *omsg, *op, *np;
- uchar_t *sp, *sp0, *dp, *dp0, *spend;
- ushort_t fcs;
- u_int32_t *xaccm, lcp_xaccm[8];
- static uchar_t lcphdr[PPP_HDRLEN] = { 0xff, 0x03, 0xc0, 0x21 };
- uchar_t ppphdr[PPP_HDRLEN];
-
- state = (ahdlc_state_t *) q->q_ptr;
- ilen = msgdsize(mp);
-
- /*
- * We estimate the length of the output packet as
- * 1.25 * input length + 16 (for initial flag, FCS, final flag, slop).
- */
- olen = ilen + (ilen >> 2) + 16;
- if (olen > OFRAME_BSIZE)
- olen = OFRAME_BSIZE;
- omsg = op = allocb(olen, BPRI_MED);
- if (omsg == 0)
- goto bomb;
-
- /*
- * Put in an initial flag for now. We'll remove it later
- * if we decide we don't need it.
- */
- dp = op->b_wptr;
- *dp++ = PPP_FLAG;
- --olen;
-
- /*
- * For LCP packets, we must escape all control characters.
- * Inspect the first PPP_HDRLEN bytes of the message to
- * see whether it is an LCP packet.
- * LCP packets must not be A/C or protocol compressed.
- */
- xaccm = state->xaccm;
- if (msg_copy(ppphdr, mp, PPP_HDRLEN) == PPP_HDRLEN
- && bcmp((caddr_t) ppphdr, (caddr_t) lcphdr, PPP_HDRLEN) == 0) {
- bcopy((caddr_t) state->xaccm, (caddr_t) lcp_xaccm, sizeof(lcp_xaccm));
- lcp_xaccm[0] = ~0;
- xaccm = lcp_xaccm;
- }
-
- sp = mp->b_rptr;
- fcs = PPP_INITFCS;
- for (;;) {
- spend = mp->b_wptr;
- extra = sp + olen - spend;
- if (extra < 0) {
- spend = sp + olen;
- extra = 0;
- }
- /*
- * We can safely process the input up to `spend'
- * without overrunning the output, provided we don't
- * hit more than `extra' characters which need to be escaped.
- */
- sp0 = sp;
- dp0 = dp;
- while (sp < spend) {
- c = *sp;
- if (ESCAPE(c, xaccm)) {
- if (extra > 0)
- --extra;
- else if (sp < spend - 1)
- --spend;
- else
- break;
- fcs = PPP_FCS(fcs, c);
- *dp++ = PPP_ESCAPE;
- c ^= PPP_TRANS;
- } else
- fcs = PPP_FCS(fcs, c);
- *dp++ = c;
- ++sp;
- }
- ilen -= sp - sp0;
- olen -= dp - dp0;
-
- /*
- * At this point, we have emptied an input block
- * and/or filled an output block.
- */
- if (sp >= mp->b_wptr) {
- /*
- * We've emptied an input block. Advance to the next.
- */
- mp = mp->b_cont;
- if (mp == 0)
- break; /* all done */
- sp = mp->b_rptr;
- }
- if (olen < 2) {
- /*
- * The output block is full. Allocate a new one.
- */
- op->b_wptr = dp;
- olen = 2 * ilen + 5;
- if (olen > OFRAME_BSIZE)
- olen = OFRAME_BSIZE;
- np = allocb(olen, BPRI_MED);
- if (np == 0)
- goto bomb;
- op->b_cont = np;
- op = np;
- dp = op->b_wptr;
- }
- }
-
- /*
- * Append the FCS and closing flag.
- * This could require up to 5 characters.
- */
- if (olen < 5) {
- /* Sigh. Need another block. */
- op->b_wptr = dp;
- np = allocb(5, BPRI_MED);
- if (np == 0)
- goto bomb;
- op->b_cont = np;
- op = np;
- dp = op->b_wptr;
- }
- c = ~fcs & 0xff;
- if (ESCAPE(c, xaccm)) {
- *dp++ = PPP_ESCAPE;
- c ^= PPP_TRANS;
- }
- *dp++ = c;
- c = (~fcs >> 8) & 0xff;
- if (ESCAPE(c, xaccm)) {
- *dp++ = PPP_ESCAPE;
- c ^= PPP_TRANS;
- }
- *dp++ = c;
- *dp++ = PPP_FLAG;
- op->b_wptr = dp;
-
- /*
- * Remove the initial flag, if possible.
- */
- if (qsize(q->q_next) > 0)
- ++omsg->b_rptr;
-
- /*
- * Update statistics.
- */
- state->stats.ppp_obytes += msgdsize(omsg);
- state->stats.ppp_opackets++;
-
- /*
- * Send it on.
- */
- putnext(q, omsg);
- return;
-
- bomb:
- if (omsg != 0)
- freemsg(omsg);
- state->stats.ppp_oerrors++;
- putctl1(RD(q)->q_next, M_CTL, PPPCTL_OERROR);
-}
-
-static unsigned paritytab[8] = {
- 0x96696996, 0x69969669, 0x69969669, 0x96696996,
- 0x69969669, 0x96696996, 0x96696996, 0x69969669
-};
-
-#define UPDATE_FLAGS(c) { \
- if ((c) & 0x80) \
- state->flags |= RCV_B7_1; \
- else \
- state->flags |= RCV_B7_0; \
- if (paritytab[(c) >> 5] & (1 << ((c) & 0x1F))) \
- state->flags |= RCV_ODDP; \
- else \
- state->flags |= RCV_EVNP; \
-}
-
-/*
- * Process received characters.
- */
-static void
-unstuff_chars(q, mp)
- queue_t *q;
- mblk_t *mp;
-{
- ahdlc_state_t *state;
- mblk_t *om;
- uchar_t *cp, *cpend, *dp, *dp0;
- int c, len, extra, offset;
- ushort_t fcs;
-
- state = (ahdlc_state_t *) q->q_ptr;
- state->stats.ppp_ibytes += msgdsize(mp);
- cp = mp->b_rptr;
- for (;;) {
- /*
- * Advance to next input block if necessary.
- */
- if (cp >= mp->b_wptr) {
- mp = mp->b_cont;
- if (mp == 0)
- break;
- cp = mp->b_rptr;
- continue;
- }
-
- if ((state->flags & (IFLUSH|ESCAPED)) == 0
- && state->inlen > 0 && (om = state->cur_blk) != 0) {
- /*
- * Process bulk chars as quickly as possible.
- */
- dp = om->b_wptr;
- len = om->b_datap->db_lim - dp; /* max # output bytes */
- extra = (mp->b_wptr - cp) - len;/* #input chars - #output bytes */
- if (extra < 0) {
- len += extra; /* we'll run out of input first */
- extra = 0;
- }
- cpend = cp + len;
- dp0 = dp;
- fcs = state->infcs;
- while (cp < cpend) {
- c = *cp;
- if (c == PPP_FLAG)
- break;
- ++cp;
- UPDATE_FLAGS(c);
- if (c == PPP_ESCAPE) {
- if (extra > 0) {
- --extra;
- ++cpend;
- }
- if (cp >= cpend || (c = *cp) == PPP_FLAG) {
- state->flags |= ESCAPED;
- break;
- }
- ++cp;
- UPDATE_FLAGS(c);
- c ^= PPP_TRANS;
- }
- *dp++ = c;
- fcs = PPP_FCS(fcs, c);
- }
- state->inlen += dp - dp0;
- state->infcs = fcs;
- om->b_wptr = dp;
- if (cp >= mp->b_wptr)
- continue; /* advance to the next mblk */
- }
-
- c = *cp++;
- UPDATE_FLAGS(c);
- if (c == PPP_FLAG) {
- /*
- * End of a frame.
- * If the ESCAPE flag is set, the frame ended with
- * the frame abort sequence "}~".
- */
- om = state->cur_frame;
- len = state->inlen;
- state->cur_frame = 0;
- state->inlen = 0;
- if (len == 0 && (state->flags & IFLUSH) == 0)
- continue;
- state->stats.ppp_ipackets++;
- if (om != 0 && (state->flags & (IFLUSH|ESCAPED)) == 0
- && len > PPP_FCSLEN) {
- if (state->infcs == PPP_GOODFCS) {
- adjmsg(om, -PPP_FCSLEN); /* chop off fcs */
- putnext(q, om); /* bombs away! */
- continue;
- }
-#if DEBUG
- cmn_err(CE_CONT, "ppp_ahdl: bad fcs %x\n", state->infcs);
-#endif
- }
- if (om != 0)
- freemsg(om);
- state->stats.ppp_ierrors++;
- putctl1(q->q_next, M_CTL, PPPCTL_IERROR);
- continue;
- }
-
- if (state->flags & IFLUSH)
- continue;
- if (state->flags & ESCAPED) {
- c ^= PPP_TRANS;
- state->flags &= ~ESCAPED;
- } else if (c == PPP_ESCAPE) {
- state->flags |= ESCAPED;
- continue;
- }
- if (state->inlen == 0) {
- /*
- * First byte of the frame: allocate the first message block.
- */
- om = allocb(IFRAME_BSIZE, BPRI_MED);
- if (om == 0) {
- state->flags |= IFLUSH;
- continue;
- }
- state->cur_frame = om;
- state->cur_blk = om;
- state->infcs = PPP_INITFCS;
- } else {
- om = state->cur_blk;
- if (om->b_wptr >= om->b_datap->db_lim) {
- /*
- * Current message block is full. Allocate another one,
- * unless we have run out of MRU.
- */
- if (state->inlen >= state->mru + PPP_HDRLEN + PPP_FCSLEN) {
-#if DEBUG
- cmn_err(CE_CONT, "ppp_ahdl: frame too long (%d)\n",
- state->inlen);
-#endif
- state->flags |= IFLUSH;
- continue;
- }
- om = allocb(IFRAME_BSIZE, BPRI_MED);
- if (om == 0) {
- state->flags |= IFLUSH;
- continue;
- }
- state->cur_blk->b_cont = om;
- state->cur_blk = om;
- }
- }
-
- if (state->inlen == 0) {
- /*
- * We don't do address/control & protocol decompression here,
- * but we try to put the first byte at an offset such that
- * the info field starts on a word boundary. The code here
- * will do this except for packets with protocol compression
- * but not address/control compression.
- */
- if (c != PPP_ALLSTATIONS) {
- om->b_wptr += 2;
- if (c & 1)
- ++om->b_wptr;
- om->b_rptr = om->b_wptr;
- }
- }
-
- *om->b_wptr++ = c;
- ++state->inlen;
- state->infcs = PPP_FCS(state->infcs, c);
- }
-}
-
-static int
-msg_copy(buf, mp, n)
- uchar_t *buf;
- mblk_t *mp;
- int n;
-{
- int i;
- uchar_t *cp;
-
- cp = mp->b_rptr;
- for (i = 0; i < n; ++i) {
- if (cp >= mp->b_wptr) {
- do {
- if ((mp = mp->b_cont) == 0)
- return i;
- } while (mp->b_rptr >= mp->b_wptr);
- cp = mp->b_rptr;
- }
- buf[i] = *cp++;
- }
- return n;
-}