/* * ppp_ahdlc.c - STREAMS module for doing PPP asynchronous HDLC. * * Re-written by Adi Masputra , based on * the original ppp_ahdlc.c * * Copyright (c) 2000 by Sun Microsystems, Inc. * 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. * * SUN MAKES NO REPRESENTATION OR WARRANTIES ABOUT THE SUITABILITY OF * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES * * 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 HAS 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. * * $Id$ */ /* * This file is used under Solaris 2, SVR4, SunOS 4, and Digital UNIX. */ #include #include #include #include #ifdef SVR4 #include #include #include #include #else #include #ifdef __osf__ #include #endif #endif /* SVR4 */ #include #include #include "ppp_mod.h" /* * Right now, mutex is only enabled for Solaris 2.x */ #if defined(SOL2) #define USE_MUTEX #endif /* SOL2 */ /* * intpointer_t and uintpointer_t are signed and unsigned integer types * large enough to hold any data pointer; that is, data pointers can be * assigned into or from these integer types without losing precision. * On recent Solaris releases, these types are defined in sys/int_types.h, * but not on SunOS 4.x or the earlier Solaris versions. */ #if defined(_LP64) || defined(_I32LPx) typedef long intpointer_t; typedef unsigned long uintpointer_t; #else typedef int intpointer_t; typedef unsigned int uintpointer_t; #endif MOD_OPEN_DECL(ahdlc_open); MOD_CLOSE_DECL(ahdlc_close); static int ahdlc_wput __P((queue_t *, mblk_t *)); static int ahdlc_rput __P((queue_t *, mblk_t *)); static void ahdlc_encode __P((queue_t *, mblk_t *)); static void ahdlc_decode __P((queue_t *, mblk_t *)); static int msg_byte __P((mblk_t *, unsigned int)); #if defined(SOL2) /* * Don't send HDLC start flag is last transmit is within 1.5 seconds - * FLAG_TIME is defined is microseconds */ #define FLAG_TIME 1500 #define ABS(x) (x >= 0 ? x : (-x)) #endif /* SOL2 */ /* * Extract byte i of message mp */ #define MSG_BYTE(mp, i) ((i) < (mp)->b_wptr - (mp)->b_rptr? (mp)->b_rptr[i]: \ msg_byte((mp), (i))) /* * Is this LCP packet one we have to transmit using LCP defaults? */ #define LCP_USE_DFLT(mp) (1 <= (code = MSG_BYTE((mp), 4)) && code <= 7) /* * Standard STREAMS declarations */ static struct module_info minfo = { 0x7d23, "ppp_ahdl", 0, INFPSZ, 32768, 512 }; 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 }; #if defined(SVR4) && !defined(SOL2) int phdldevflag = 0; #define ppp_ahdlcinfo phdlinfo #endif /* defined(SVR4) && !defined(SOL2) */ struct streamtab ppp_ahdlcinfo = { &rinit, /* ptr to st_rdinit */ &winit, /* ptr to st_wrinit */ NULL, /* ptr to st_muxrinit */ NULL, /* ptr to st_muxwinit */ #if defined(SUNOS4) NULL /* ptr to ptr to st_modlist */ #endif /* SUNOS4 */ }; #if defined(SUNOS4) int ppp_ahdlc_count = 0; /* open counter */ #endif /* SUNOS4 */ /* * Per-stream state structure */ typedef struct ahdlc_state { #if defined(USE_MUTEX) kmutex_t lock; /* lock for this structure */ #endif /* USE_MUTEX */ int flags; /* link flags */ mblk_t *rx_buf; /* ptr to receive buffer */ int rx_buf_size; /* receive buffer size */ ushort_t infcs; /* calculated rx HDLC FCS */ u_int32_t xaccm[8]; /* 256-bit xmit ACCM */ u_int32_t raccm; /* 32-bit rcv ACCM */ int mtu; /* interface MTU */ int mru; /* link MRU */ int unit; /* current PPP unit number */ struct pppstat stats; /* statistic structure */ #if defined(SOL2) clock_t flag_time; /* time in usec between flags */ clock_t lbolt; /* last updated lbolt */ #endif /* SOL2 */ } 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) /* * 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 }; static u_int32_t paritytab[8] = { 0x96696996, 0x69969669, 0x69969669, 0x96696996, 0x69969669, 0x96696996, 0x96696996, 0x69969669 }; /* * STREAMS module open (entry) point */ MOD_OPEN(ahdlc_open) { ahdlc_state_t *state; /* * Return if it's already opened */ if (q->q_ptr) { return 0; } /* * This can only be opened as a module */ if (sflag != MODOPEN) { return 0; } state = (ahdlc_state_t *) ALLOC_NOSLEEP(sizeof(ahdlc_state_t)); if (state == 0) OPEN_ERROR(ENOSR); bzero((caddr_t) state, sizeof(ahdlc_state_t)); q->q_ptr = (caddr_t) state; WR(q)->q_ptr = (caddr_t) state; #if defined(USE_MUTEX) mutex_init(&state->lock, NULL, MUTEX_DEFAULT, NULL); mutex_enter(&state->lock); #endif /* USE_MUTEX */ state->xaccm[0] = ~0; /* escape 0x00 through 0x1f */ state->xaccm[3] = 0x60000000; /* escape 0x7d and 0x7e */ state->mru = PPP_MRU; /* default of 1500 bytes */ #if defined(SOL2) state->flag_time = drv_usectohz(FLAG_TIME); #endif /* SOL2 */ #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ #if defined(SUNOS4) ppp_ahdlc_count++; #endif /* SUNOS4 */ qprocson(q); return 0; } /* * STREAMS module close (exit) point */ MOD_CLOSE(ahdlc_close) { ahdlc_state_t *state; qprocsoff(q); state = (ahdlc_state_t *) q->q_ptr; if (state == 0) { DPRINT("state == 0 in ahdlc_close\n"); return 0; } #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ if (state->rx_buf != 0) { freemsg(state->rx_buf); state->rx_buf = 0; } #if defined(USE_MUTEX) mutex_exit(&state->lock); mutex_destroy(&state->lock); #endif /* USE_MUTEX */ FREE(q->q_ptr, sizeof(ahdlc_state_t)); q->q_ptr = NULL; OTHERQ(q)->q_ptr = NULL; #if defined(SUNOS4) if (ppp_ahdlc_count) ppp_ahdlc_count--; #endif /* SUNOS4 */ return 0; } /* * Write side put routine */ 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; if (state == 0) { DPRINT("state == 0 in ahdlc_wput\n"); freemsg(mp); return 0; } switch (mp->b_datap->db_type) { case M_DATA: /* * A data packet - do character-stuffing and FCS, and * send it onwards. */ ahdlc_encode(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; } if (mp->b_cont == 0) { DPRINT1("ahdlc_wput/%d: PPPIO_XACCM b_cont = 0!\n", state->unit); break; } #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ bcopy((caddr_t)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 */ #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ iop->ioc_count = 0; error = 0; break; case PPPIO_RACCM: if (iop->ioc_count != sizeof(u_int32_t)) break; if (mp->b_cont == 0) { DPRINT1("ahdlc_wput/%d: PPPIO_RACCM b_cont = 0!\n", state->unit); break; } #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ bcopy((caddr_t)mp->b_cont->b_rptr, (caddr_t)&state->raccm, sizeof(u_int32_t)); #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ 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; #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ *(int *)np->b_wptr = state->flags & RCV_FLAGS; #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ 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: #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ state->mtu = ((unsigned short *)mp->b_rptr)[1]; #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ freemsg(mp); break; case PPPCTL_MRU: #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ state->mru = ((unsigned short *)mp->b_rptr)[1]; #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ freemsg(mp); break; case PPPCTL_UNIT: #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ state->unit = mp->b_rptr[1]; #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ break; default: putnext(q, mp); } break; default: putnext(q, mp); } return 0; } /* * Read side put routine */ static int ahdlc_rput(q, mp) queue_t *q; mblk_t *mp; { ahdlc_state_t *state; state = (ahdlc_state_t *) q->q_ptr; if (state == 0) { DPRINT("state == 0 in ahdlc_rput\n"); freemsg(mp); return 0; } switch (mp->b_datap->db_type) { case M_DATA: ahdlc_decode(q, mp); freemsg(mp); break; case M_HANGUP: #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ if (state->rx_buf != 0) { /* XXX would like to send this up for debugging */ freemsg(state->rx_buf); state->rx_buf = 0; } state->flags = IFLUSH; #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ 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 IN_TX_MAP(c, m) ((m)[(c) >> 5] & (1 << ((c) & 0x1f))) static void ahdlc_encode(q, mp) queue_t *q; mblk_t *mp; { ahdlc_state_t *state; u_int32_t *xaccm, loc_xaccm[8]; ushort_t fcs; size_t outmp_len; mblk_t *outmp, *tmp; uchar_t *dp, fcs_val; int is_lcp, code; #if defined(SOL2) clock_t lbolt; #endif /* SOL2 */ if (msgdsize(mp) < 4) { return; } state = (ahdlc_state_t *)q->q_ptr; #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ /* * Allocate an output buffer large enough to handle a case where all * characters need to be escaped */ outmp_len = (msgdsize(mp) << 1) + /* input block x 2 */ (sizeof(fcs) << 2) + /* HDLC FCS x 4 */ (sizeof(uchar_t) << 1); /* HDLC flags x 2 */ outmp = allocb(outmp_len, BPRI_MED); if (outmp == NULL) { state->stats.ppp_oerrors++; #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ putctl1(RD(q)->q_next, M_CTL, PPPCTL_OERROR); return; } #if defined(SOL2) /* * Check if our last transmit happenned within flag_time, using * the system's LBOLT value in clock ticks */ if (drv_getparm(LBOLT, &lbolt) != -1) { if (ABS((clock_t)lbolt - state->lbolt) > state->flag_time) { *outmp->b_wptr++ = PPP_FLAG; } state->lbolt = lbolt; } else { *outmp->b_wptr++ = PPP_FLAG; } #else /* * If the driver below still has a message to process, skip the * HDLC flag, otherwise, put one in the beginning */ if (qsize(q->q_next) == 0) { *outmp->b_wptr++ = PPP_FLAG; } #endif /* * All control characters must be escaped for LCP packets with code * values between 1 (Conf-Req) and 7 (Code-Rej). */ is_lcp = ((MSG_BYTE(mp, 0) == PPP_ALLSTATIONS) && (MSG_BYTE(mp, 1) == PPP_UI) && (MSG_BYTE(mp, 2) == (PPP_LCP >> 8)) && (MSG_BYTE(mp, 3) == (PPP_LCP & 0xff)) && LCP_USE_DFLT(mp)); xaccm = state->xaccm; if (is_lcp) { bcopy((caddr_t)state->xaccm, (caddr_t)loc_xaccm, sizeof(loc_xaccm)); loc_xaccm[0] = ~0; /* force escape on 0x00 through 0x1f */ xaccm = loc_xaccm; } fcs = PPP_INITFCS; /* Initial FCS is 0xffff */ /* * Process this block and the rest (if any) attached to the this one */ for (tmp = mp; tmp; tmp = tmp->b_cont) { if (tmp->b_datap->db_type == M_DATA) { for (dp = tmp->b_rptr; dp < tmp->b_wptr; dp++) { fcs = PPP_FCS(fcs, *dp); if (IN_TX_MAP(*dp, xaccm)) { *outmp->b_wptr++ = PPP_ESCAPE; *outmp->b_wptr++ = *dp ^ PPP_TRANS; } else { *outmp->b_wptr++ = *dp; } } } else { continue; /* skip if db_type is something other than M_DATA */ } } /* * Append the HDLC FCS, making sure that escaping is done on any * necessary bytes */ fcs_val = (fcs ^ 0xffff) & 0xff; if (IN_TX_MAP(fcs_val, xaccm)) { *outmp->b_wptr++ = PPP_ESCAPE; *outmp->b_wptr++ = fcs_val ^ PPP_TRANS; } else { *outmp->b_wptr++ = fcs_val; } fcs_val = ((fcs ^ 0xffff) >> 8) & 0xff; if (IN_TX_MAP(fcs_val, xaccm)) { *outmp->b_wptr++ = PPP_ESCAPE; *outmp->b_wptr++ = fcs_val ^ PPP_TRANS; } else { *outmp->b_wptr++ = fcs_val; } /* * And finally, append the HDLC flag, and send it away */ *outmp->b_wptr++ = PPP_FLAG; state->stats.ppp_obytes += msgdsize(outmp); state->stats.ppp_opackets++; #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ putnext(q, outmp); return; } /* * Checks the 32-bit receive ACCM to see if the byte needs un-escaping */ #define IN_RX_MAP(c, m) ((((unsigned int) (uchar_t) (c)) < 0x20) && \ (m) & (1 << (c))) /* * Process received characters. */ static void ahdlc_decode(q, mp) queue_t *q; mblk_t *mp; { ahdlc_state_t *state; mblk_t *om; uchar_t *dp; ushort_t fcs; #if defined(SOL2) mblk_t *zmp; #endif /* SOL2 */ #if defined(SOL2) /* * In case the driver (or something below) doesn't send * data upstream in one message block, concatenate everything */ if (!((mp->b_wptr - mp->b_rptr == msgdsize(mp)) && ((intpointer_t)mp->b_rptr % sizeof(intpointer_t) == 0))) { zmp = msgpullup(mp, -1); freemsg(mp); mp = zmp; if (mp == 0) return; } #endif /* SOL2 */ state = (ahdlc_state_t *) q->q_ptr; #if defined(USE_MUTEX) mutex_enter(&state->lock); #endif /* USE_MUTEX */ state->stats.ppp_ibytes += msgdsize(mp); for (dp = mp->b_rptr; dp < mp->b_wptr; dp++) { /* * This should detect the lack of 8-bit communication channel * which is necessary for PPP to work. In addition, it also * checks on the parity. */ if (*dp & 0x80) state->flags |= RCV_B7_1; else state->flags |= RCV_B7_0; if (paritytab[*dp >> 5] & (1 << (*dp & 0x1f))) state->flags |= RCV_ODDP; else state->flags |= RCV_EVNP; /* * So we have a HDLC flag ... */ if (*dp == PPP_FLAG) { /* * If we think that it marks the beginning of the frame, * then continue to process the next octects */ if ((state->flags & IFLUSH) || (state->rx_buf == 0) || (msgdsize(state->rx_buf) == 0)) { state->flags &= ~IFLUSH; continue; } /* * We get here because the above condition isn't true, * in which case the HDLC flag was there to mark the end * of the frame (or so we think) */ om = state->rx_buf; if (state->infcs == PPP_GOODFCS) { state->stats.ppp_ipackets++; adjmsg(om, -PPP_FCSLEN); putnext(q, om); } else { DPRINT2("ppp%d: bad fcs (len=%d)\n", state->unit, msgdsize(state->rx_buf)); freemsg(state->rx_buf); state->flags &= ~(IFLUSH | ESCAPED); state->stats.ppp_ierrors++; putctl1(q->q_next, M_CTL, PPPCTL_IERROR); } state->rx_buf = 0; continue; } if (state->flags & IFLUSH) { continue; } /* * Allocate a receive buffer, large enough to store a frame (after * un-escaping) of at least 1500 octets. If MRU is negotiated to * be more than the default, then allocate that much. In addition, * we add an extra 32-bytes for a fudge factor */ if (state->rx_buf == 0) { state->rx_buf_size = (state->mru < PPP_MRU ? PPP_MRU : state->mru); state->rx_buf_size += (sizeof(u_int32_t) << 3); state->rx_buf = allocb(state->rx_buf_size, BPRI_MED); /* * If allocation fails, try again on the next frame */ if (state->rx_buf == 0) { state->flags |= IFLUSH; continue; } state->flags &= ~(IFLUSH | ESCAPED); state->infcs = PPP_INITFCS; } if (*dp == PPP_ESCAPE) { state->flags |= ESCAPED; continue; } /* * Make sure we un-escape the necessary characters, as well as the * ones in our receive async control character map */ if (state->flags & ESCAPED) { *dp ^= PPP_TRANS; state->flags &= ~ESCAPED; } else if (IN_RX_MAP(*dp, state->raccm)) continue; /* * Unless the peer lied to us about the negotiated MRU, we should * never get a frame which is too long. If it happens, toss it away * and grab the next incoming one */ if (msgdsize(state->rx_buf) < state->rx_buf_size) { state->infcs = PPP_FCS(state->infcs, *dp); *state->rx_buf->b_wptr++ = *dp; } else { DPRINT2("ppp%d: frame too long (%d)\n", state->unit, msgdsize(state->rx_buf)); freemsg(state->rx_buf); state->rx_buf = 0; state->flags |= IFLUSH; } } #if defined(USE_MUTEX) mutex_exit(&state->lock); #endif /* USE_MUTEX */ } static int msg_byte(mp, i) mblk_t *mp; unsigned int i; { while (mp != 0 && i >= mp->b_wptr - mp->b_rptr) mp = mp->b_cont; if (mp == 0) return -1; return mp->b_rptr[i]; }