/* * ppp_tty.c - Point-to-Point Protocol (PPP) driver for asynchronous * tty devices. * * Copyright (c) 1989 Carnegie Mellon University. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by Carnegie Mellon University. The name of the * University may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. * * Drew D. Perkins * Carnegie Mellon University * 4910 Forbes Ave. * Pittsburgh, PA 15213 * (412) 268-8576 * ddp@andrew.cmu.edu * * Based on: * @(#)if_sl.c 7.6.1.2 (Berkeley) 2/15/89 * * Copyright (c) 1987 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by the University of California, Berkeley. The name of the * University may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. * * Serial Line interface * * Rick Adams * Center for Seismic Studies * 1300 N 17th Street, Suite 1450 * Arlington, Virginia 22209 * (703)276-7900 * rick@seismo.ARPA * seismo!rick * * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris). * Converted to 4.3BSD Beta by Chris Torek. * Other changes made at Berkeley, based in part on code by Kirk Smith. * * Converted to 4.3BSD+ 386BSD by Brad Parker (brad@cayman.com) * Added VJ tcp header compression; more unified ioctls * * Extensively modified by Paul Mackerras (paulus@cs.anu.edu.au). * Cleaned up a lot of the mbuf-related code to fix bugs that * caused system crashes and packet corruption. Changed pppstart * so that it doesn't just give up with a "collision" if the whole * packet doesn't fit in the output ring buffer. * * Added priority queueing for interactive IP packets, following * the model of if_sl.c, plus hooks for bpf. * Paul Mackerras (paulus@cs.anu.edu.au). */ /* $FreeBSD$ */ #include "opt_ppp.h" /* XXX for ppp_defs.h */ #define VJC /* XXX for ppp_defs.h */ #include #include #include #include #include #include #include #include #include #include #include #ifdef PPP_FILTER #include #endif #include #include static int pppopen __P((dev_t dev, struct tty *tp)); static int pppclose __P((struct tty *tp, int flag)); static int pppread __P((struct tty *tp, struct uio *uio, int flag)); static int pppwrite __P((struct tty *tp, struct uio *uio, int flag)); static int ppptioctl __P((struct tty *tp, u_long cmd, caddr_t data, int flag, struct thread *td)); static int pppinput __P((int c, struct tty *tp)); static int pppstart __P((struct tty *tp)); static u_short pppfcs __P((u_short fcs, u_char *cp, int len)); static void pppasyncstart __P((struct ppp_softc *)); static void pppasyncctlp __P((struct ppp_softc *)); static void pppasyncrelinq __P((struct ppp_softc *)); static void pppasyncsetmtu __P((struct ppp_softc *)); static void ppp_timeout __P((void *)); static void pppgetm __P((struct ppp_softc *sc)); static void ppplogchar __P((struct ppp_softc *, int)); /* XXX called from if_ppp.c - layering violation */ void pppasyncattach __P((void *)); /* * Some useful mbuf macros not in mbuf.h. */ #define M_IS_CLUSTER(m) ((m)->m_flags & M_EXT) #define M_DATASTART(m) \ (M_IS_CLUSTER(m) ? (m)->m_ext.ext_buf : \ (m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat) #define M_DATASIZE(m) \ (M_IS_CLUSTER(m) ? (m)->m_ext.ext_size : \ (m)->m_flags & M_PKTHDR ? MHLEN: MLEN) /* * Does c need to be escaped? */ #define ESCAPE_P(c) (sc->sc_asyncmap[(c) >> 5] & (1 << ((c) & 0x1F))) /* * Procedures for using an async tty interface for PPP. */ /* This is a FreeBSD-2.X kernel. */ #define CCOUNT(q) ((q)->c_cc) #define PPP_LOWAT 100 /* Process more output when < LOWAT on queue */ #define PPP_HIWAT 400 /* Don't start a new packet if HIWAT on que */ /* * Define the PPP line discipline. */ static struct linesw pppdisc = { pppopen, pppclose, pppread, pppwrite, ppptioctl, pppinput, pppstart, ttymodem, PPP_FLAG }; void pppasyncattach(dummy) void *dummy; { /* register line discipline */ linesw[PPPDISC] = pppdisc; } /* * Line specific open routine for async tty devices. * Attach the given tty to the first available ppp unit. * Called from device open routine or ttioctl() at >= splsofttty() */ /* ARGSUSED */ static int pppopen(dev, tp) dev_t dev; register struct tty *tp; { struct thread *td = curthread; /* XXX */ register struct ppp_softc *sc; int error, s; if ((error = suser_td(td)) != 0) return (error); s = spltty(); if (tp->t_line == PPPDISC) { sc = (struct ppp_softc *) tp->t_sc; if (sc != NULL && sc->sc_devp == (void *) tp) { splx(s); return (0); } } if ((sc = pppalloc(td->td_proc->p_pid)) == NULL) { splx(s); return ENXIO; } if (sc->sc_relinq) (*sc->sc_relinq)(sc); /* get previous owner to relinquish the unit */ sc->sc_ilen = 0; sc->sc_m = NULL; bzero(sc->sc_asyncmap, sizeof(sc->sc_asyncmap)); sc->sc_asyncmap[0] = 0xffffffff; sc->sc_asyncmap[3] = 0x60000000; sc->sc_rasyncmap = 0; sc->sc_devp = (void *) tp; sc->sc_start = pppasyncstart; sc->sc_ctlp = pppasyncctlp; sc->sc_relinq = pppasyncrelinq; sc->sc_setmtu = pppasyncsetmtu; sc->sc_outm = NULL; pppgetm(sc); sc->sc_if.if_flags |= IFF_RUNNING; getmicrotime(&sc->sc_if.if_lastchange); sc->sc_if.if_baudrate = tp->t_ospeed; tp->t_sc = (caddr_t) sc; ttyflush(tp, FREAD | FWRITE); /* * Pre-allocate cblocks to the "just right" amount. The 1 byte t_canq * allocation helps avoid the need for select and/or FIONREAD. * We also pass 1 byte tokens through t_canq... */ clist_alloc_cblocks(&tp->t_canq, 1, 1); clist_alloc_cblocks(&tp->t_outq, sc->sc_if.if_mtu + PPP_HIWAT, sc->sc_if.if_mtu + PPP_HIWAT); clist_alloc_cblocks(&tp->t_rawq, 0, 0); splx(s); return (0); } /* * Line specific close routine, called from device close routine * and from ttioctl at >= splsofttty(). * Detach the tty from the ppp unit. * Mimics part of ttyclose(). */ static int pppclose(tp, flag) struct tty *tp; int flag; { register struct ppp_softc *sc; int s; s = spltty(); ttyflush(tp, FREAD | FWRITE); clist_free_cblocks(&tp->t_canq); clist_free_cblocks(&tp->t_outq); tp->t_line = 0; sc = (struct ppp_softc *) tp->t_sc; if (sc != NULL) { tp->t_sc = NULL; if (tp == (struct tty *) sc->sc_devp) { pppasyncrelinq(sc); pppdealloc(sc); } } splx(s); return 0; } /* * Relinquish the interface unit to another device. */ static void pppasyncrelinq(sc) struct ppp_softc *sc; { int s; s = spltty(); if (sc->sc_outm) { m_freem(sc->sc_outm); sc->sc_outm = NULL; } if (sc->sc_m) { m_freem(sc->sc_m); sc->sc_m = NULL; } if (sc->sc_flags & SC_TIMEOUT) { untimeout(ppp_timeout, (void *) sc, sc->sc_ch); sc->sc_flags &= ~SC_TIMEOUT; } splx(s); } /* * This gets called from the upper layer to notify a mtu change */ static void pppasyncsetmtu(sc) register struct ppp_softc *sc; { register struct tty *tp = (struct tty *) sc->sc_devp; int s; s = spltty(); if (tp != NULL) clist_alloc_cblocks(&tp->t_outq, sc->sc_if.if_mtu + PPP_HIWAT, sc->sc_if.if_mtu + PPP_HIWAT); splx(s); } /* * Line specific (tty) read routine. * called at zero spl from the device driver in the response to user-level * reads on the tty file descriptor (ie: pppd). */ static int pppread(tp, uio, flag) register struct tty *tp; struct uio *uio; int flag; { register struct ppp_softc *sc = (struct ppp_softc *)tp->t_sc; struct mbuf *m, *m0; register int s; int error = 0; if (sc == NULL) return 0; /* * Loop waiting for input, checking that nothing disasterous * happens in the meantime. */ s = spltty(); for (;;) { if (tp != (struct tty *) sc->sc_devp || tp->t_line != PPPDISC) { splx(s); return 0; } if (sc->sc_inq.ifq_head != NULL) break; if ((tp->t_state & TS_CONNECTED) == 0) { splx(s); return 0; /* end of file */ } if (tp->t_state & TS_ASYNC || flag & IO_NDELAY) { splx(s); return (EWOULDBLOCK); } error = ttysleep(tp, TSA_HUP_OR_INPUT(tp), TTIPRI | PCATCH, "pppin", 0); if (error) { splx(s); return error; } } /* Pull place-holder byte out of canonical queue */ getc(&tp->t_canq); /* Get the packet from the input queue */ IF_DEQUEUE(&sc->sc_inq, m0); splx(s); for (m = m0; m && uio->uio_resid; m = m->m_next) if ((error = uiomove(mtod(m, u_char *), m->m_len, uio)) != 0) break; m_freem(m0); return (error); } /* * Line specific (tty) write routine. * called at zero spl from the device driver in the response to user-level * writes on the tty file descriptor (ie: pppd). */ static int pppwrite(tp, uio, flag) register struct tty *tp; struct uio *uio; int flag; { register struct ppp_softc *sc = (struct ppp_softc *)tp->t_sc; struct mbuf *m, *m0, **mp; struct sockaddr dst; int len, error, s; if ((tp->t_state & TS_CONNECTED) == 0) return 0; /* wrote 0 bytes */ if (tp->t_line != PPPDISC) return (EINVAL); if (sc == NULL || tp != (struct tty *) sc->sc_devp) return EIO; if (uio->uio_resid > sc->sc_if.if_mtu + PPP_HDRLEN || uio->uio_resid < PPP_HDRLEN) return (EMSGSIZE); s = spltty(); for (mp = &m0; uio->uio_resid; mp = &m->m_next) { MGET(m, M_TRYWAIT, MT_DATA); if ((*mp = m) == NULL) { m_freem(m0); splx(s); return (ENOBUFS); } m->m_len = 0; if (uio->uio_resid >= MCLBYTES / 2) MCLGET(m, M_DONTWAIT); len = M_TRAILINGSPACE(m); if (len > uio->uio_resid) len = uio->uio_resid; if ((error = uiomove(mtod(m, u_char *), len, uio)) != 0) { m_freem(m0); splx(s); return (error); } m->m_len = len; } dst.sa_family = AF_UNSPEC; bcopy(mtod(m0, u_char *), dst.sa_data, PPP_HDRLEN); m0->m_data += PPP_HDRLEN; m0->m_len -= PPP_HDRLEN; /* call the upper layer to "transmit" it... */ error = pppoutput(&sc->sc_if, m0, &dst, (struct rtentry *)0); splx(s); return (error); } /* * Line specific (tty) ioctl routine. * This discipline requires that tty device drivers call * the line specific l_ioctl routine from their ioctl routines. */ /* ARGSUSED */ static int ppptioctl(tp, cmd, data, flag, td) struct tty *tp; u_long cmd; caddr_t data; int flag; struct thread *td; { struct ppp_softc *sc = (struct ppp_softc *) tp->t_sc; int error, s; if (sc == NULL || tp != (struct tty *) sc->sc_devp) return (ENOIOCTL); error = 0; switch (cmd) { case PPPIOCSASYNCMAP: if ((error = suser_td(td)) != 0) break; sc->sc_asyncmap[0] = *(u_int *)data; break; case PPPIOCGASYNCMAP: *(u_int *)data = sc->sc_asyncmap[0]; break; case PPPIOCSRASYNCMAP: if ((error = suser_td(td)) != 0) break; sc->sc_rasyncmap = *(u_int *)data; break; case PPPIOCGRASYNCMAP: *(u_int *)data = sc->sc_rasyncmap; break; case PPPIOCSXASYNCMAP: if ((error = suser_td(td)) != 0) break; s = spltty(); bcopy(data, sc->sc_asyncmap, sizeof(sc->sc_asyncmap)); sc->sc_asyncmap[1] = 0; /* mustn't escape 0x20 - 0x3f */ sc->sc_asyncmap[2] &= ~0x40000000; /* mustn't escape 0x5e */ sc->sc_asyncmap[3] |= 0x60000000; /* must escape 0x7d, 0x7e */ splx(s); break; case PPPIOCGXASYNCMAP: bcopy(sc->sc_asyncmap, data, sizeof(sc->sc_asyncmap)); break; default: error = pppioctl(sc, cmd, data, flag, td); if (error == 0 && cmd == PPPIOCSMRU) pppgetm(sc); } return error; } /* * 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 }; /* * Calculate a new FCS given the current FCS and the new data. */ static u_short pppfcs(u_short fcs, u_char *cp, int len) { while (len--) fcs = PPP_FCS(fcs, *cp++); return (fcs); } /* * This gets called at splsoftnet from if_ppp.c at various times * when there is data ready to be sent. */ static void pppasyncstart(sc) register struct ppp_softc *sc; { register struct tty *tp = (struct tty *) sc->sc_devp; register struct mbuf *m; register int len; register u_char *start, *stop, *cp; int n, ndone, done, idle; int s; idle = 0; /* XXX assumes atomic access to *tp although we're not at spltty(). */ while (CCOUNT(&tp->t_outq) < PPP_HIWAT) { /* * See if we have an existing packet partly sent. * If not, get a new packet and start sending it. */ m = sc->sc_outm; if (m == NULL) { /* * Get another packet to be sent. */ m = ppp_dequeue(sc); if (m == NULL) { idle = 1; break; } /* * The extra PPP_FLAG will start up a new packet, and thus * will flush any accumulated garbage. We do this whenever * the line may have been idle for some time. */ /* XXX as above. */ if (CCOUNT(&tp->t_outq) == 0) { ++sc->sc_stats.ppp_obytes; (void) putc(PPP_FLAG, &tp->t_outq); } /* Calculate the FCS for the first mbuf's worth. */ sc->sc_outfcs = pppfcs(PPP_INITFCS, mtod(m, u_char *), m->m_len); getmicrotime(&sc->sc_if.if_lastchange); } for (;;) { start = mtod(m, u_char *); len = m->m_len; stop = start + len; while (len > 0) { /* * Find out how many bytes in the string we can * handle without doing something special. */ for (cp = start; cp < stop; cp++) if (ESCAPE_P(*cp)) break; n = cp - start; if (n) { /* NetBSD (0.9 or later), 4.3-Reno or similar. */ ndone = n - b_to_q(start, n, &tp->t_outq); len -= ndone; start += ndone; sc->sc_stats.ppp_obytes += ndone; if (ndone < n) break; /* packet doesn't fit */ } /* * If there are characters left in the mbuf, * the first one must be special. * Put it out in a different form. */ if (len) { s = spltty(); if (putc(PPP_ESCAPE, &tp->t_outq)) { splx(s); break; } if (putc(*start ^ PPP_TRANS, &tp->t_outq)) { (void) unputc(&tp->t_outq); splx(s); break; } splx(s); sc->sc_stats.ppp_obytes += 2; start++; len--; } } /* * If we didn't empty this mbuf, remember where we're up to. * If we emptied the last mbuf, try to add the FCS and closing * flag, and if we can't, leave sc_outm pointing to m, but with * m->m_len == 0, to remind us to output the FCS and flag later. */ done = len == 0; if (done && m->m_next == NULL) { u_char *p, *q; int c; u_char endseq[8]; /* * We may have to escape the bytes in the FCS. */ p = endseq; c = ~sc->sc_outfcs & 0xFF; if (ESCAPE_P(c)) { *p++ = PPP_ESCAPE; *p++ = c ^ PPP_TRANS; } else *p++ = c; c = (~sc->sc_outfcs >> 8) & 0xFF; if (ESCAPE_P(c)) { *p++ = PPP_ESCAPE; *p++ = c ^ PPP_TRANS; } else *p++ = c; *p++ = PPP_FLAG; /* * Try to output the FCS and flag. If the bytes * don't all fit, back out. */ s = spltty(); for (q = endseq; q < p; ++q) if (putc(*q, &tp->t_outq)) { done = 0; for (; q > endseq; --q) unputc(&tp->t_outq); break; } splx(s); if (done) sc->sc_stats.ppp_obytes += q - endseq; } if (!done) { /* remember where we got to */ m->m_data = start; m->m_len = len; break; } /* Finished with this mbuf; free it and move on. */ m = m_free(m); if (m == NULL) { /* Finished a packet */ break; } sc->sc_outfcs = pppfcs(sc->sc_outfcs, mtod(m, u_char *), m->m_len); } /* * If m == NULL, we have finished a packet. * If m != NULL, we've either done as much work this time * as we need to, or else we've filled up the output queue. */ sc->sc_outm = m; if (m) break; } /* Call pppstart to start output again if necessary. */ s = spltty(); pppstart(tp); /* * This timeout is needed for operation on a pseudo-tty, * because the pty code doesn't call pppstart after it has * drained the t_outq. */ if (!idle && (sc->sc_flags & SC_TIMEOUT) == 0) { sc->sc_ch = timeout(ppp_timeout, (void *) sc, 1); sc->sc_flags |= SC_TIMEOUT; } splx(s); } /* * This gets called when a received packet is placed on * the inq, at splsoftnet. The pppd daemon is to be woken up to do a read(). */ static void pppasyncctlp(sc) struct ppp_softc *sc; { struct tty *tp; int s; /* Put a placeholder byte in canq for ttselect()/ttnread(). */ s = spltty(); tp = (struct tty *) sc->sc_devp; putc(0, &tp->t_canq); ttwakeup(tp); splx(s); } /* * Start output on async tty interface. If the transmit queue * has drained sufficiently, arrange for pppasyncstart to be * called later at splsoftnet. * Called at spltty or higher. */ int pppstart(tp) register struct tty *tp; { register struct ppp_softc *sc = (struct ppp_softc *) tp->t_sc; /* * Call output process whether or not there is any output. * We are being called in lieu of ttstart and must do what it would. */ if (tp->t_oproc != NULL) (*tp->t_oproc)(tp); /* * If the transmit queue has drained and the tty has not hung up * or been disconnected from the ppp unit, then tell if_ppp.c that * we need more output. */ if (CCOUNT(&tp->t_outq) < PPP_LOWAT && !((tp->t_state & TS_CONNECTED) == 0) && sc != NULL && tp == (struct tty *) sc->sc_devp) { ppp_restart(sc); } return 0; } /* * Timeout routine - try to start some more output. */ static void ppp_timeout(x) void *x; { struct ppp_softc *sc = (struct ppp_softc *) x; struct tty *tp = (struct tty *) sc->sc_devp; int s; s = spltty(); sc->sc_flags &= ~SC_TIMEOUT; pppstart(tp); splx(s); } /* * Allocate enough mbuf to handle current MRU. */ static void pppgetm(sc) register struct ppp_softc *sc; { struct mbuf *m, **mp; int len; mp = &sc->sc_m; for (len = sc->sc_mru + PPP_HDRLEN + PPP_FCSLEN; len > 0; ){ if ((m = *mp) == NULL) { MGETHDR(m, M_DONTWAIT, MT_DATA); if (m == NULL) break; *mp = m; MCLGET(m, M_DONTWAIT); } len -= M_DATASIZE(m); mp = &m->m_next; } } /* * tty interface receiver interrupt. */ static unsigned paritytab[8] = { 0x96696996, 0x69969669, 0x69969669, 0x96696996, 0x69969669, 0x96696996, 0x96696996, 0x69969669 }; /* * Called when character is available from device driver. * Only guaranteed to be at splsofttty() or spltty() * This is safe to be called while the upper half's netisr is preempted. */ static int pppinput(c, tp) int c; register struct tty *tp; { register struct ppp_softc *sc; struct mbuf *m; int ilen, s; sc = (struct ppp_softc *) tp->t_sc; if (sc == NULL || tp != (struct tty *) sc->sc_devp) return 0; ++tk_nin; ++sc->sc_stats.ppp_ibytes; if ((tp->t_state & TS_CONNECTED) == 0) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: no carrier\n", sc->sc_if.if_unit); goto flush; } if (c & TTY_ERRORMASK) { /* framing error or overrun on this char - abort packet */ if (sc->sc_flags & SC_DEBUG) printf("ppp%d: line error %x\n", sc->sc_if.if_unit, c & TTY_ERRORMASK); goto flush; } c &= TTY_CHARMASK; /* * Handle software flow control of output. */ if (tp->t_iflag & IXON) { if (c == tp->t_cc[VSTOP] && tp->t_cc[VSTOP] != _POSIX_VDISABLE) { if ((tp->t_state & TS_TTSTOP) == 0) { tp->t_state |= TS_TTSTOP; tp->t_stop(tp, 0); } return 0; } if (c == tp->t_cc[VSTART] && tp->t_cc[VSTART] != _POSIX_VDISABLE) { tp->t_state &= ~TS_TTSTOP; if (tp->t_oproc != NULL) (*tp->t_oproc)(tp); return 0; } } s = spltty(); if (c & 0x80) sc->sc_flags |= SC_RCV_B7_1; else sc->sc_flags |= SC_RCV_B7_0; if (paritytab[c >> 5] & (1 << (c & 0x1F))) sc->sc_flags |= SC_RCV_ODDP; else sc->sc_flags |= SC_RCV_EVNP; splx(s); if (sc->sc_flags & SC_LOG_RAWIN) ppplogchar(sc, c); if (c == PPP_FLAG) { ilen = sc->sc_ilen; sc->sc_ilen = 0; if (sc->sc_rawin_count > 0) ppplogchar(sc, -1); /* * If SC_ESCAPED is set, then we've seen the packet * abort sequence "}~". */ if (sc->sc_flags & (SC_FLUSH | SC_ESCAPED) || (ilen > 0 && sc->sc_fcs != PPP_GOODFCS)) { s = spltty(); sc->sc_flags |= SC_PKTLOST; /* note the dropped packet */ if ((sc->sc_flags & (SC_FLUSH | SC_ESCAPED)) == 0){ if (sc->sc_flags & SC_DEBUG) printf("ppp%d: bad fcs %x, pkt len %d\n", sc->sc_if.if_unit, sc->sc_fcs, ilen); sc->sc_if.if_ierrors++; sc->sc_stats.ppp_ierrors++; } else sc->sc_flags &= ~(SC_FLUSH | SC_ESCAPED); splx(s); return 0; } if (ilen < PPP_HDRLEN + PPP_FCSLEN) { if (ilen) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: too short (%d)\n", sc->sc_if.if_unit, ilen); s = spltty(); sc->sc_if.if_ierrors++; sc->sc_stats.ppp_ierrors++; sc->sc_flags |= SC_PKTLOST; splx(s); } return 0; } /* * Remove FCS trailer. Somewhat painful... */ ilen -= 2; if (--sc->sc_mc->m_len == 0) { for (m = sc->sc_m; m->m_next != sc->sc_mc; m = m->m_next) ; sc->sc_mc = m; } sc->sc_mc->m_len--; /* excise this mbuf chain */ m = sc->sc_m; sc->sc_m = sc->sc_mc->m_next; sc->sc_mc->m_next = NULL; ppppktin(sc, m, sc->sc_flags & SC_PKTLOST); if (sc->sc_flags & SC_PKTLOST) { s = spltty(); sc->sc_flags &= ~SC_PKTLOST; splx(s); } pppgetm(sc); return 0; } if (sc->sc_flags & SC_FLUSH) { if (sc->sc_flags & SC_LOG_FLUSH) ppplogchar(sc, c); return 0; } if (c < 0x20 && (sc->sc_rasyncmap & (1 << c))) return 0; s = spltty(); if (sc->sc_flags & SC_ESCAPED) { sc->sc_flags &= ~SC_ESCAPED; c ^= PPP_TRANS; } else if (c == PPP_ESCAPE) { sc->sc_flags |= SC_ESCAPED; splx(s); return 0; } splx(s); /* * Initialize buffer on first octet received. * First octet could be address or protocol (when compressing * address/control). * Second octet is control. * Third octet is first or second (when compressing protocol) * octet of protocol. * Fourth octet is second octet of protocol. */ if (sc->sc_ilen == 0) { /* reset the first input mbuf */ if (sc->sc_m == NULL) { pppgetm(sc); if (sc->sc_m == NULL) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: no input mbufs!\n", sc->sc_if.if_unit); goto flush; } } m = sc->sc_m; m->m_len = 0; m->m_data = M_DATASTART(sc->sc_m); sc->sc_mc = m; sc->sc_mp = mtod(m, char *); sc->sc_fcs = PPP_INITFCS; if (c != PPP_ALLSTATIONS) { if (sc->sc_flags & SC_REJ_COMP_AC) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: garbage received: 0x%x (need 0xFF)\n", sc->sc_if.if_unit, c); goto flush; } *sc->sc_mp++ = PPP_ALLSTATIONS; *sc->sc_mp++ = PPP_UI; sc->sc_ilen += 2; m->m_len += 2; } } if (sc->sc_ilen == 1 && c != PPP_UI) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: missing UI (0x3), got 0x%x\n", sc->sc_if.if_unit, c); goto flush; } if (sc->sc_ilen == 2 && (c & 1) == 1) { /* a compressed protocol */ *sc->sc_mp++ = 0; sc->sc_ilen++; sc->sc_mc->m_len++; } if (sc->sc_ilen == 3 && (c & 1) == 0) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: bad protocol %x\n", sc->sc_if.if_unit, (sc->sc_mp[-1] << 8) + c); goto flush; } /* packet beyond configured mru? */ if (++sc->sc_ilen > sc->sc_mru + PPP_HDRLEN + PPP_FCSLEN) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: packet too big\n", sc->sc_if.if_unit); goto flush; } /* is this mbuf full? */ m = sc->sc_mc; if (M_TRAILINGSPACE(m) <= 0) { if (m->m_next == NULL) { pppgetm(sc); if (m->m_next == NULL) { if (sc->sc_flags & SC_DEBUG) printf("ppp%d: too few input mbufs!\n", sc->sc_if.if_unit); goto flush; } } sc->sc_mc = m = m->m_next; m->m_len = 0; m->m_data = M_DATASTART(m); sc->sc_mp = mtod(m, char *); } ++m->m_len; *sc->sc_mp++ = c; sc->sc_fcs = PPP_FCS(sc->sc_fcs, c); return 0; flush: if (!(sc->sc_flags & SC_FLUSH)) { s = spltty(); sc->sc_if.if_ierrors++; sc->sc_stats.ppp_ierrors++; sc->sc_flags |= SC_FLUSH; splx(s); if (sc->sc_flags & SC_LOG_FLUSH) ppplogchar(sc, c); } return 0; } #define MAX_DUMP_BYTES 128 static void ppplogchar(sc, c) struct ppp_softc *sc; int c; { if (c >= 0) sc->sc_rawin[sc->sc_rawin_count++] = c; if (sc->sc_rawin_count >= sizeof(sc->sc_rawin) || (c < 0 && sc->sc_rawin_count > 0)) { printf("ppp%d input: %*D", sc->sc_if.if_unit, sc->sc_rawin_count, sc->sc_rawin, " "); sc->sc_rawin_count = 0; } }