add BPF support. compress all packets. stabilize error-prone lines.

SCCS-vsn: sys/net/if_sl.c 8.4
SCCS-vsn: sys/net/if_slvar.h 8.2

diff --git a/usr/src/sys/net/if_sl.c b/usr/src/sys/net/if_sl.c
index 478d77a..a335be6 100644 (file)
--- a/usr/src/sys/net/if_sl.c
+++ b/usr/src/sys/net/if_sl.c
@@ -4,7 +4,7 @@
  *
  * %sccs.include.redist.c%
  *
  *
  * %sccs.include.redist.c%
  *

- *     @(#)if_sl.c     8.3 (Berkeley) %G%
+ *     @(#)if_sl.c     8.4 (Berkeley) %G%

  */
 
 /*
  */
 
 /*


@@ -41,6 +41,8 @@
 #include "sl.h"
 #if NSL > 0
 
 #include "sl.h"
 #if NSL > 0
 

+#include "bpfilter.h"
+

 #include <sys/param.h>
 #include <sys/proc.h>
 #include <sys/mbuf.h>
 #include <sys/param.h>
 #include <sys/proc.h>
 #include <sys/mbuf.h>


@@ -72,6 +74,11 @@ Huh? Slip without inet?
 #include <net/slcompress.h>
 #include <net/if_slvar.h>
 
 #include <net/slcompress.h>
 #include <net/if_slvar.h>
 

+#if NBPFILTER > 0
+#include <sys/time.h>
+#include <net/bpf.h>
+#endif
+

 /*
  * SLMAX is a hard limit on input packet size.  To simplify the code
  * and improve performance, we require that packets fit in an mbuf
 /*
  * SLMAX is a hard limit on input packet size.  To simplify the code
  * and improve performance, we require that packets fit in an mbuf


@@ -112,7 +119,11 @@ Huh? Slip without inet?
  * time.  So, setting SLIP_HIWAT to ~100 guarantees that we'll lose
  * at most 1% while maintaining good interactive response.
  */
  * time.  So, setting SLIP_HIWAT to ~100 guarantees that we'll lose
  * at most 1% while maintaining good interactive response.
  */

-#define BUFOFFSET      128
+#if NBPFILTER > 0
+#define        BUFOFFSET       (128+sizeof(struct ifnet **)+SLIP_HDRLEN)
+#else
+#define        BUFOFFSET       (128+sizeof(struct ifnet **))
+#endif

 #define        SLMAX           (MCLBYTES - BUFOFFSET)
 #define        SLBUFSIZE       (SLMAX + BUFOFFSET)
 #define        SLMTU           296
 #define        SLMAX           (MCLBYTES - BUFOFFSET)
 #define        SLBUFSIZE       (SLMAX + BUFOFFSET)
 #define        SLMTU           296


@@ -127,9 +138,9 @@ Huh? Slip without inet?
  *     if the IFF_DEBUG flag is on.
  */
 #define        ABT_ESC         '\033'  /* can't be t_intr - distant host must know it*/
  *     if the IFF_DEBUG flag is on.
  */
 #define        ABT_ESC         '\033'  /* can't be t_intr - distant host must know it*/

-#define ABT_IDLE       1       /* in seconds - idle before an escape */
-#define ABT_COUNT      3       /* count of escapes for abort */
-#define ABT_WINDOW     (ABT_COUNT*2+2) /* in seconds - time to count */
+#define        ABT_IDLE        1       /* in seconds - idle before an escape */
+#define        ABT_COUNT       3       /* count of escapes for abort */
+#define        ABT_WINDOW      (ABT_COUNT*2+2) /* in seconds - time to count */

 
 struct sl_softc sl_softc[NSL];
 
 
 struct sl_softc sl_softc[NSL];
 


@@ -165,6 +176,9 @@ slattach()
                sc->sc_if.if_snd.ifq_maxlen = 50;
                sc->sc_fastq.ifq_maxlen = 32;
                if_attach(&sc->sc_if);
                sc->sc_if.if_snd.ifq_maxlen = 50;
                sc->sc_fastq.ifq_maxlen = 32;
                if_attach(&sc->sc_if);

+#if NBPFILTER > 0
+               bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_SLIP, SLIP_HDRLEN);
+#endif

        }
 }
 
        }
 }
 


@@ -264,6 +278,7 @@ sltioctl(tp, cmd, data, flag)
        int flag;
 {
        struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
        int flag;
 {
        struct sl_softc *sc = (struct sl_softc *)tp->t_sc;

+       int s;

 
        switch (cmd) {
        case SLIOCGUNIT:
 
        switch (cmd) {
        case SLIOCGUNIT:


@@ -278,6 +293,9 @@ sltioctl(tp, cmd, data, flag)
 
 /*
  * Queue a packet.  Start transmission if not active.
 
 /*
  * Queue a packet.  Start transmission if not active.

+ * Compression happens in slstart; if we do it here, IP TOS
+ * will cause us to not compress "background" packets, because
+ * ordering gets trashed.  It can be done for all packets in slstart.

  */
 int
 sloutput(ifp, m, dst, rtp)
  */
 int
 sloutput(ifp, m, dst, rtp)


@@ -289,7 +307,6 @@ sloutput(ifp, m, dst, rtp)
        register struct sl_softc *sc = &sl_softc[ifp->if_unit];
        register struct ip *ip;
        register struct ifqueue *ifq;
        register struct sl_softc *sc = &sl_softc[ifp->if_unit];
        register struct ip *ip;
        register struct ifqueue *ifq;

-       register int p;

        int s;
 
        /*
        int s;
 
        /*


@@ -308,33 +325,19 @@ sloutput(ifp, m, dst, rtp)
                m_freem(m);
                return (ENETDOWN);      /* sort of */
        }
                m_freem(m);
                return (ENETDOWN);      /* sort of */
        }

-       if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0) {
+       if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 &&
+           (sc->sc_ttyp->t_cflag & CLOCAL) == 0) {

                m_freem(m);
                return (EHOSTUNREACH);
        }
        ifq = &sc->sc_if.if_snd;
        ip = mtod(m, struct ip *);
                m_freem(m);
                return (EHOSTUNREACH);
        }
        ifq = &sc->sc_if.if_snd;
        ip = mtod(m, struct ip *);

-       if (ip->ip_tos & IPTOS_LOWDELAY) {
-               ifq = &sc->sc_fastq;
-               p = 1;
-       } else
-               p = 0;
-       if (ip->ip_p == IPPROTO_TCP) {
-               if (sc->sc_if.if_flags & SC_COMPRESS) {
-                       /*
-                        * The last parameter turns off connection id
-                        * compression for background traffic:  Since
-                        * fastq traffic can jump ahead of the background
-                        * traffic, we don't know what order packets will
-                        * go on the line.
-                        */
-                       p = sl_compress_tcp(m, ip, &sc->sc_comp, p);
-                       *mtod(m, u_char *) |= p;
-               }
-       } else if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) {
+       if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) {

                m_freem(m);
                return (ENETRESET);             /* XXX ? */
        }
                m_freem(m);
                return (ENETRESET);             /* XXX ? */
        }

+       if (ip->ip_tos & IPTOS_LOWDELAY)
+               ifq = &sc->sc_fastq;

        s = splimp();
        if (IF_QFULL(ifq)) {
                IF_DROP(ifq);
        s = splimp();
        if (IF_QFULL(ifq)) {
                IF_DROP(ifq);


@@ -363,8 +366,13 @@ slstart(tp)
        register struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
        register struct mbuf *m;
        register u_char *cp;
        register struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
        register struct mbuf *m;
        register u_char *cp;

+       register struct ip *ip;

        int s;
        struct mbuf *m2;
        int s;
        struct mbuf *m2;

+#if NBPFILTER > 0
+       u_char bpfbuf[SLMTU + SLIP_HDRLEN];
+       register int len;
+#endif

        extern int cfreecount;
 
        for (;;) {
        extern int cfreecount;
 
        for (;;) {


@@ -396,6 +404,53 @@ slstart(tp)
                splx(s);
                if (m == NULL)
                        return;
                splx(s);
                if (m == NULL)
                        return;

+
+               /*
+                * We do the header compression here rather than in sloutput
+                * because the packets will be out of order if we are using TOS
+                * queueing, and the connection id compression will get
+                * munged when this happens.
+                */
+#if NBPFILTER > 0
+               if (sc->sc_bpf) {
+                       /*
+                        * We need to save the TCP/IP header before it's
+                        * compressed.  To avoid complicated code, we just
+                        * copy the entire packet into a stack buffer (since
+                        * this is a serial line, packets should be short
+                        * and/or the copy should be negligible cost compared
+                        * to the packet transmission time).
+                        */
+                       register struct mbuf *m1 = m;
+                       register u_char *cp = bpfbuf + SLIP_HDRLEN;
+
+                       len = 0;
+                       do {
+                               register int mlen = m1->m_len;
+
+                               bcopy(mtod(m1, caddr_t), cp, mlen);
+                               cp += mlen;
+                               len += mlen;
+                       } while (m1 = m1->m_next);
+               }
+#endif
+               if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) {
+                       if (sc->sc_if.if_flags & SC_COMPRESS)
+                               *mtod(m, u_char *) |= sl_compress_tcp(m, ip,
+                                   &sc->sc_comp, 1);
+               }
+#if NBPFILTER > 0
+               if (sc->sc_bpf) {
+                       /*
+                        * Put the SLIP pseudo-"link header" in place.  The
+                        * compressed header is now at the beginning of the
+                        * mbuf.
+                        */
+                       bpfbuf[SLX_DIR] = SLIPDIR_OUT;
+                       bcopy(mtod(m, caddr_t), &bpfbuf[SLX_CHDR], CHDR_LEN);
+                       bpf_tap(sc->sc_bpf, bpfbuf, len + SLIP_HDRLEN);
+               }
+#endif

                sc->sc_if.if_lastchange = time;
 
                /*
                sc->sc_if.if_lastchange = time;
 
                /*


@@ -443,7 +498,8 @@ slstart(tp)
                                         * Put n characters at once
                                         * into the tty output queue.
                                         */
                                         * Put n characters at once
                                         * into the tty output queue.
                                         */

-                                       if (b_to_q((char *)bp, cp - bp, &tp->t_outq))
+                                       if (b_to_q((char *)bp, cp - bp,
+                                           &tp->t_outq))

                                                break;
                                        sc->sc_if.if_obytes += cp - bp;
                                }
                                                break;
                                        sc->sc_if.if_obytes += cp - bp;
                                }


@@ -541,18 +597,23 @@ slinput(c, tp)
        register struct mbuf *m;
        register int len;
        int s;
        register struct mbuf *m;
        register int len;
        int s;

+#if NBPFILTER > 0
+       u_char chdr[CHDR_LEN];
+#endif

 
        tk_nin++;
        sc = (struct sl_softc *)tp->t_sc;
        if (sc == NULL)
                return;
 
        tk_nin++;
        sc = (struct sl_softc *)tp->t_sc;
        if (sc == NULL)
                return;

-       if (!(tp->t_state&TS_CARR_ON))  /* XXX */
+       if (c & TTY_ERRORMASK || ((tp->t_state & TS_CARR_ON) == 0 &&
+           (tp->t_cflag & CLOCAL) == 0)) {
+               sc->sc_flags |= SC_ERROR;

                return;
                return;

+       }
+       c &= TTY_CHARMASK;

 
        ++sc->sc_if.if_ibytes;
 
        ++sc->sc_if.if_ibytes;

-       c &= 0xff;                      /* XXX */

 
 

-#ifdef ABT_ESC

        if (sc->sc_if.if_flags & IFF_DEBUG) {
                if (c == ABT_ESC) {
                        /*
        if (sc->sc_if.if_flags & IFF_DEBUG) {
                if (c == ABT_ESC) {
                        /*


@@ -578,7 +639,6 @@ slinput(c, tp)
                        sc->sc_abortcount = 0;
                sc->sc_lasttime = time.tv_sec;
        }
                        sc->sc_abortcount = 0;
                sc->sc_lasttime = time.tv_sec;
        }

-#endif

 
        switch (c) {
 
 
        switch (c) {
 


@@ -597,11 +657,29 @@ slinput(c, tp)
                return;
 
        case FRAME_END:
                return;
 
        case FRAME_END:

+               if(sc->sc_flags & SC_ERROR) {
+                       sc->sc_flags &= ~SC_ERROR;
+                       goto newpack;
+               }

                len = sc->sc_mp - sc->sc_buf;
                if (len < 3)
                        /* less than min length packet - ignore */
                        goto newpack;
 
                len = sc->sc_mp - sc->sc_buf;
                if (len < 3)
                        /* less than min length packet - ignore */
                        goto newpack;
 

+#if NBPFILTER > 0
+               if (sc->sc_bpf) {
+                       /*
+                        * Save the compressed header, so we
+                        * can tack it on later.  Note that we
+                        * will end up copying garbage in some
+                        * cases but this is okay.  We remember
+                        * where the buffer started so we can
+                        * compute the new header length.
+                        */
+                       bcopy(sc->sc_buf, chdr, CHDR_LEN);
+               }
+#endif
+

                if ((c = (*sc->sc_buf & 0xf0)) != (IPVERSION << 4)) {
                        if (c & 0x80)
                                c = TYPE_COMPRESSED_TCP;
                if ((c = (*sc->sc_buf & 0xf0)) != (IPVERSION << 4)) {
                        if (c & 0x80)
                                c = TYPE_COMPRESSED_TCP;


@@ -629,6 +707,21 @@ slinput(c, tp)
                        } else
                                goto error;
                }
                        } else
                                goto error;
                }

+#if NBPFILTER > 0
+               if (sc->sc_bpf) {
+                       /*
+                        * Put the SLIP pseudo-"link header" in place.
+                        * We couldn't do this any earlier since
+                        * decompression probably moved the buffer
+                        * pointer.  Then, invoke BPF.
+                        */
+                       register u_char *hp = sc->sc_buf - SLIP_HDRLEN;
+
+                       hp[SLX_DIR] = SLIPDIR_IN;
+                       bcopy(chdr, &hp[SLX_CHDR], CHDR_LEN);
+                       bpf_tap(sc->sc_bpf, hp, len + SLIP_HDRLEN);
+               }
+#endif

                m = sl_btom(sc, len);
                if (m == NULL)
                        goto error;
                m = sl_btom(sc, len);
                if (m == NULL)
                        goto error;


@@ -653,6 +746,10 @@ slinput(c, tp)
                sc->sc_escape = 0;
                return;
        }
                sc->sc_escape = 0;
                return;
        }

+
+       /* can't put lower; would miss an extra frame */
+       sc->sc_flags |= SC_ERROR;
+

 error:
        sc->sc_if.if_ierrors++;
 newpack:
 error:
        sc->sc_if.if_ierrors++;
 newpack:


@@ -706,7 +803,6 @@ slioctl(ifp, cmd, data)
                        break;
                }
                break;
                        break;
                }
                break;

-#endif

 
        default:
                error = EINVAL;
 
        default:
                error = EINVAL;


@@ -714,3 +810,4 @@ slioctl(ifp, cmd, data)
        splx(s);
        return (error);
 }
        splx(s);
        return (error);
 }

+#endif

diff --git a/usr/src/sys/net/if_slvar.h b/usr/src/sys/net/if_slvar.h
index 8f65a08..eb9b146 100644 (file)
--- a/usr/src/sys/net/if_slvar.h
+++ b/usr/src/sys/net/if_slvar.h
@@ -4,7 +4,7 @@
  *
  * %sccs.include.redist.c%
  *
  *
  * %sccs.include.redist.c%
  *

- *     @(#)if_slvar.h  8.1 (Berkeley) %G%
+ *     @(#)if_slvar.h  8.2 (Berkeley) %G%

  *
  * $Header: if_slvar.h,v 1.3 89/05/31 02:25:18 van Exp $
  */
  *
  * $Header: if_slvar.h,v 1.3 89/05/31 02:25:18 van Exp $
  */


@@ -30,8 +30,12 @@ struct sl_softc {
 #ifdef INET                            /* XXX */
        struct  slcompress sc_comp;     /* tcp compression data */
 #endif
 #ifdef INET                            /* XXX */
        struct  slcompress sc_comp;     /* tcp compression data */
 #endif

+       caddr_t sc_bpf;                 /* BPF data */

 };
 
 };
 

+/* internal flags */
+#define        SC_ERROR        0x0001          /* had an input error */
+

 /* visible flags */
 #define        SC_COMPRESS     IFF_LINK0       /* compress TCP traffic */
 #define        SC_NOICMP       IFF_LINK1       /* supress ICMP traffic */
 /* visible flags */
 #define        SC_COMPRESS     IFF_LINK0       /* compress TCP traffic */
 #define        SC_NOICMP       IFF_LINK1       /* supress ICMP traffic */


@@ -40,14 +44,29 @@ struct sl_softc {
 /* this stuff doesn't belong here... */
 #define        SLIOCGUNIT      _IOR('t', 88, int)      /* get slip unit number */
 
 /* this stuff doesn't belong here... */
 #define        SLIOCGUNIT      _IOR('t', 88, int)      /* get slip unit number */
 

+/*
+ * definitions of the pseudo- link-level header attached to slip
+ * packets grabbed by the packet filter (bpf) traffic monitor.
+ * These definitions pulled from BPF's "slip.h" by cgd.
+ */
+#define        SLIP_HDRLEN     16              /* BPF SLIP header length */
+
+/* offsets into BPF SLIP header */
+#define        SLX_DIR         0               /* direction; see below */
+#define        SLX_CHDR        1               /* compressed header data */
+#define        CHDR_LEN        15              /* length of compressed header data */
+
+#define        SLIPDIR_IN      0               /* incoming */
+#define        SLIPDIR_OUT     1               /* outgoing */
+

 #ifdef KERNEL
 #ifdef KERNEL

-void    slattach __P((void));
-void    slclose __P((struct tty *));
-void    slinput __P((int, struct tty *));
-int     slioctl __P((struct ifnet *, int, caddr_t));
-int     slopen __P((dev_t, struct tty *));
-int     sloutput __P((struct ifnet *,
+void   slattach __P((void));
+void   slclose __P((struct tty *));
+void   slinput __P((int, struct tty *));
+int    slioctl __P((struct ifnet *, int, caddr_t));
+int    slopen __P((dev_t, struct tty *));
+int    sloutput __P((struct ifnet *,

            struct mbuf *, struct sockaddr *, struct rtentry *));
            struct mbuf *, struct sockaddr *, struct rtentry *));

-void    slstart __P((struct tty *));
-int     sltioctl __P((struct tty *, int, caddr_t, int));
-#endif
+void   slstart __P((struct tty *));
+int    sltioctl __P((struct tty *, int, caddr_t, int));
+#endif /* KERNEL */