1 files changed, 541 insertions, 0 deletions

diff --git a/sys/kern/tty_snoop.c b/sys/kern/tty_snoop.c
new file mode 100644
index 0000000..ba71a94
--- /dev/null
+++ b/sys/kern/tty_snoop.c
@@ -0,0 +1,541 @@
+/*
+ * Copyright (c) 1995 Ugen J.S.Antsilevich
+ *
+ * Redistribution and use in source forms, with and without modification,
+ * are permitted provided that this entire comment appears intact.
+ *
+ * Redistribution in binary form may occur without any restrictions.
+ * Obviously, it would be nice if you gave credit where credit is due
+ * but requiring it would be too onerous.
+ *
+ * This software is provided ``AS IS'' without any warranties of any kind.
+ *
+ * Snoop stuff.
+ */
+
+#include "snp.h"
+
+#if NSNP > 0
+
+#include "opt_compat.h"
+#include "opt_devfs.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/filio.h>
+#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
+#include <sys/ioctl_compat.h>
+#endif
+#include <sys/proc.h>
+#include <sys/malloc.h>
+#include <sys/tty.h>
+#include <sys/conf.h>
+#include <sys/poll.h>
+#include <sys/kernel.h>
+#ifdef DEVFS
+#include <sys/devfsext.h>
+#endif /*DEVFS*/
+#include <sys/snoop.h>
+#include <sys/vnode.h>
+
+static	d_open_t	snpopen;
+static	d_close_t	snpclose;
+static	d_read_t	snpread;
+static	d_write_t	snpwrite;
+static	d_ioctl_t	snpioctl;
+static	d_poll_t	snppoll;
+
+#define CDEV_MAJOR 53
+static struct cdevsw snp_cdevsw = 
+	{ snpopen,	snpclose,	snpread,	snpwrite,	/*53*/
+	  snpioctl,	nostop,		nullreset,	nodevtotty,/* snoop */
+	  snppoll,	nommap,		NULL,	"snp",	NULL,	-1 };
+
+
+#ifndef MIN
+#define MIN(a,b) (((a)<(b))?(a):(b))
+#endif
+
+static struct snoop snoopsw[NSNP];
+
+static struct tty	*snpdevtotty __P((dev_t dev));
+static int		snp_detach __P((struct snoop *snp));
+
+static struct tty *
+snpdevtotty (dev)
+	dev_t		dev;
+{
+	struct cdevsw	*cdp;
+	int		maj;
+
+	maj = major(dev);
+	if ((u_int)maj >= nchrdev)
+		return (NULL);
+	cdp = cdevsw[maj];
+	if (cdp == NULL)
+		return (NULL);
+	return ((*cdp->d_devtotty)(dev));
+}
+
+#define SNP_INPUT_BUF	5	/* This is even too  much,the maximal
+				 * interactive mode write is 3 bytes
+				 * length for function keys...
+				 */
+
+static	int
+snpwrite(dev, uio, flag)
+	dev_t           dev;
+	struct uio     *uio;
+	int             flag;
+{
+	int             unit = minor(dev), len, i, error;
+	struct snoop   *snp = &snoopsw[unit];
+	struct tty     *tp;
+	char		c[SNP_INPUT_BUF];
+
+	if (snp->snp_tty == NULL)
+		return (EIO);
+
+	tp = snp->snp_tty;
+
+	if ((tp->t_sc == snp) && (tp->t_state & TS_SNOOP) &&
+	    (tp->t_line == OTTYDISC || tp->t_line == NTTYDISC))
+		goto tty_input;
+
+	printf("Snoop: attempt to write to bad tty.\n");
+	return (EIO);
+
+tty_input:
+	if (!(tp->t_state & TS_ISOPEN))
+		return (EIO);
+
+	while (uio->uio_resid > 0) {
+		len = MIN(uio->uio_resid,SNP_INPUT_BUF);
+		if ((error = uiomove(c, len, uio)) != 0)
+			return (error);
+		for (i=0;i<len;i++) {
+			if (ttyinput(c[i] , tp))
+				return (EIO);
+		}
+	}
+	return 0;
+
+}
+
+
+static	int
+snpread(dev, uio, flag)
+	dev_t           dev;
+	struct uio     *uio;
+	int             flag;
+{
+	int             unit = minor(dev), s;
+	struct snoop   *snp = &snoopsw[unit];
+	int             len, n, nblen, error = 0;
+	caddr_t         from;
+	char           *nbuf;
+
+	KASSERT(snp->snp_len + snp->snp_base <= snp->snp_blen,
+	    ("snoop buffer error"));
+
+	if (snp->snp_tty == NULL)
+		return (EIO);
+
+	snp->snp_flags &= ~SNOOP_RWAIT;
+
+	do {
+		if (snp->snp_len == 0) {
+			if (flag & IO_NDELAY)
+				return (EWOULDBLOCK);
+			snp->snp_flags |= SNOOP_RWAIT;
+			tsleep((caddr_t) snp, (PZERO + 1) | PCATCH, "snoopread", 0);
+		}
+	} while (snp->snp_len == 0);
+
+	n = snp->snp_len;
+
+	while (snp->snp_len > 0 && uio->uio_resid > 0 && error == 0) {
+		len = MIN(uio->uio_resid, snp->snp_len);
+		from = (caddr_t) (snp->snp_buf + snp->snp_base);
+		if (len == 0)
+			break;
+
+		error = uiomove(from, len, uio);
+		snp->snp_base += len;
+		snp->snp_len -= len;
+	}
+	if ((snp->snp_flags & SNOOP_OFLOW) && (n < snp->snp_len)) {
+		snp->snp_flags &= ~SNOOP_OFLOW;
+	}
+	s = spltty();
+	nblen = snp->snp_blen;
+	if (((nblen / 2) >= SNOOP_MINLEN) && (nblen / 2) >= snp->snp_len) {
+		while (((nblen / 2) >= snp->snp_len) && ((nblen / 2) >= SNOOP_MINLEN))
+			nblen = nblen / 2;
+		if (nbuf = malloc(nblen, M_TTYS, M_NOWAIT)) {
+			bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
+			free(snp->snp_buf, M_TTYS);
+			snp->snp_buf = nbuf;
+			snp->snp_blen = nblen;
+			snp->snp_base = 0;
+		}
+	}
+	splx(s);
+
+	return error;
+}
+
+int
+snpinc(struct snoop *snp, char c)
+{
+        char    buf[1];
+
+        buf[0]=c;
+        return (snpin(snp,buf,1));
+}
+
+
+int
+snpin(snp, buf, n)
+	struct snoop   *snp;
+	char           *buf;
+	int             n;
+{
+	int             s_free, s_tail;
+	int             s, len, nblen;
+	caddr_t         from, to;
+	char           *nbuf;
+
+	KASSERT(n >= 0, ("negative snoop char count"));
+
+	if (n == 0)
+		return 0;
+
+#ifdef DIAGNOSTIC
+	if (!(snp->snp_flags & SNOOP_OPEN)) {
+		printf("Snoop: data coming to closed device.\n");
+		return 0;
+	}
+#endif
+	if (snp->snp_flags & SNOOP_DOWN) {
+		printf("Snoop: more data to down interface.\n");
+		return 0;
+	}
+
+	if (snp->snp_flags & SNOOP_OFLOW) {
+		printf("Snoop: buffer overflow.\n");
+		/*
+		 * On overflow we just repeat the standart close
+		 * procedure...yes , this is waste of space but.. Then next
+		 * read from device will fail if one would recall he is
+		 * snooping and retry...
+		 */
+
+		return (snpdown(snp));
+	}
+	s_tail = snp->snp_blen - (snp->snp_len + snp->snp_base);
+	s_free = snp->snp_blen - snp->snp_len;
+
+
+	if (n > s_free) {
+		s = spltty();
+		nblen = snp->snp_blen;
+		while ((n > s_free) && ((nblen * 2) <= SNOOP_MAXLEN)) {
+			nblen = snp->snp_blen * 2;
+			s_free = nblen - (snp->snp_len + snp->snp_base);
+		}
+		if ((n <= s_free) && (nbuf = malloc(nblen, M_TTYS, M_NOWAIT))) {
+			bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
+			free(snp->snp_buf, M_TTYS);
+			snp->snp_buf = nbuf;
+			snp->snp_blen = nblen;
+			snp->snp_base = 0;
+		} else {
+			snp->snp_flags |= SNOOP_OFLOW;
+			if (snp->snp_flags & SNOOP_RWAIT) {
+				snp->snp_flags &= ~SNOOP_RWAIT;
+				wakeup((caddr_t) snp);
+			}
+			splx(s);
+			return 0;
+		}
+		splx(s);
+	}
+	if (n > s_tail) {
+		from = (caddr_t) (snp->snp_buf + snp->snp_base);
+		to = (caddr_t) (snp->snp_buf);
+		len = snp->snp_len;
+		bcopy(from, to, len);
+		snp->snp_base = 0;
+	}
+	to = (caddr_t) (snp->snp_buf + snp->snp_base + snp->snp_len);
+	bcopy(buf, to, n);
+	snp->snp_len += n;
+
+	if (snp->snp_flags & SNOOP_RWAIT) {
+		snp->snp_flags &= ~SNOOP_RWAIT;
+		wakeup((caddr_t) snp);
+	}
+	selwakeup(&snp->snp_sel);
+	snp->snp_sel.si_pid = 0;
+
+	return n;
+}
+
+static	int
+snpopen(dev, flag, mode, p)
+	dev_t           dev;
+	int             flag, mode;
+	struct proc    *p;
+{
+	struct snoop   *snp;
+	register int    unit, error;
+
+	if (error = suser(p->p_ucred, &p->p_acflag))
+		return (error);
+
+	if ((unit = minor(dev)) >= NSNP)
+		return (ENXIO);
+
+	snp = &snoopsw[unit];
+
+	if (snp->snp_flags & SNOOP_OPEN)
+		return (ENXIO);
+
+	/*
+	 * We intentionally do not OR flags with SNOOP_OPEN,but set them so
+	 * all previous settings (especially SNOOP_OFLOW) will be cleared.
+	 */
+	snp->snp_flags = SNOOP_OPEN;
+
+	snp->snp_buf = malloc(SNOOP_MINLEN, M_TTYS, M_WAITOK);
+	snp->snp_blen = SNOOP_MINLEN;
+	snp->snp_base = 0;
+	snp->snp_len = 0;
+
+	/*
+	 * snp_tty == NULL  is for inactive snoop devices.
+	 */
+	snp->snp_tty = NULL;
+	snp->snp_target = -1;
+	return (0);
+}
+
+
+static int
+snp_detach(snp)
+	struct snoop   *snp;
+{
+	struct tty     *tp;
+
+	snp->snp_base = 0;
+	snp->snp_len = 0;
+
+	/*
+	 * If line disc. changed we do not touch this pointer,SLIP/PPP will
+	 * change it anyway.
+	 */
+
+	if (snp->snp_tty == NULL)
+		goto detach_notty;
+
+	tp = snp->snp_tty;
+
+	if (tp && (tp->t_sc == snp) && (tp->t_state & TS_SNOOP) &&
+	    (tp->t_line == OTTYDISC || tp->t_line == NTTYDISC)) {
+		tp->t_sc = NULL;
+		tp->t_state &= ~TS_SNOOP;
+	} else
+		printf("Snoop: bad attached tty data.\n");
+
+	snp->snp_tty = NULL;
+	snp->snp_target = -1;
+
+detach_notty:
+	selwakeup(&snp->snp_sel);
+	snp->snp_sel.si_pid = 0;
+
+	return (0);
+}
+
+static	int
+snpclose(dev, flags, fmt, p)
+	dev_t           dev;
+	int             flags;
+	int             fmt;
+	struct proc    *p;
+{
+	register int    unit = minor(dev);
+	struct snoop   *snp = &snoopsw[unit];
+
+	snp->snp_blen = 0;
+	free(snp->snp_buf, M_TTYS);
+	snp->snp_flags &= ~SNOOP_OPEN;
+
+	return (snp_detach(snp));
+}
+
+int
+snpdown(snp)
+	struct snoop	*snp;
+{
+	snp->snp_blen = SNOOP_MINLEN;
+	free(snp->snp_buf, M_TTYS);
+	snp->snp_buf = malloc(SNOOP_MINLEN, M_TTYS, M_WAITOK);
+	snp->snp_flags |= SNOOP_DOWN;
+
+	return (snp_detach(snp));
+}
+
+
+static	int
+snpioctl(dev, cmd, data, flags, p)
+	dev_t           dev;
+	u_long          cmd;
+	caddr_t         data;
+	int             flags;
+	struct proc    *p;
+{
+	int             unit = minor(dev), s;
+	dev_t		tdev;
+	struct snoop   *snp = &snoopsw[unit];
+	struct tty     *tp, *tpo;
+
+	switch (cmd) {
+	case SNPSTTY:
+		tdev = *((dev_t *) data);
+		if (tdev == -1)
+			return (snpdown(snp));
+
+		tp = snpdevtotty(tdev);
+		if (!tp)
+			return (EINVAL);
+
+		if ((tp->t_sc != (caddr_t) snp) && (tp->t_state & TS_SNOOP))
+			return (EBUSY);
+
+		if ((tp->t_line != OTTYDISC) && (tp->t_line != NTTYDISC))
+			return (EBUSY);
+
+		s = spltty();
+
+		if (snp->snp_target == -1) {
+			tpo = snp->snp_tty;
+			if (tpo)
+				tpo->t_state &= ~TS_SNOOP;
+		}
+
+		tp->t_sc = (caddr_t) snp;
+		tp->t_state |= TS_SNOOP;
+		snp->snp_tty = tp;
+		snp->snp_target = tdev;
+
+		/*
+		 * Clean overflow and down flags -
+		 * we'll have a chance to get them in the future :)))
+		 */
+		snp->snp_flags &= ~SNOOP_OFLOW;
+		snp->snp_flags &= ~SNOOP_DOWN;
+		splx(s);
+		break;
+
+	case SNPGTTY:
+		/*
+		 * We keep snp_target field specially to make
+		 * SNPGTTY happy,else we can't know what is device
+		 * major/minor for tty.
+		 */
+		*((dev_t *) data) = snp->snp_target;
+		break;
+
+	case FIONBIO:
+		break;
+
+	case FIOASYNC:
+		if (*(int *) data)
+			snp->snp_flags |= SNOOP_ASYNC;
+		else
+			snp->snp_flags &= ~SNOOP_ASYNC;
+		break;
+
+	case FIONREAD:
+		s = spltty();
+		if (snp->snp_tty != NULL)
+			*(int *) data = snp->snp_len;
+		else
+			if (snp->snp_flags & SNOOP_DOWN) {
+				if (snp->snp_flags & SNOOP_OFLOW)
+					*(int *) data = SNP_OFLOW;
+				else
+					*(int *) data = SNP_TTYCLOSE;
+			} else {
+				*(int *) data = SNP_DETACH;
+			}
+		splx(s);
+		break;
+
+	default:
+		return (ENOTTY);
+	}
+	return (0);
+}
+
+
+static	int
+snppoll(dev, events, p)
+	dev_t           dev;
+	int             events;
+	struct proc    *p;
+{
+	int             unit = minor(dev);
+	struct snoop   *snp = &snoopsw[unit];
+	int		revents = 0;
+
+
+	/*
+	 * If snoop is down,we don't want to poll() forever so we return 1.
+	 * Caller should see if we down via FIONREAD ioctl().The last should
+	 * return -1 to indicate down state.
+	 */
+	if (events & (POLLIN | POLLRDNORM))
+		if (snp->snp_flags & SNOOP_DOWN || snp->snp_len > 0)
+			revents |= events & (POLLIN | POLLRDNORM);
+		else
+			selrecord(p, &snp->snp_sel);
+
+	return (revents);
+}
+
+#ifdef DEVFS
+static	void	*snp_devfs_token[NSNP];
+#endif
+static	int	snp_devsw_installed;
+
+static void snp_drvinit __P((void *unused));
+static void
+snp_drvinit(unused)
+	void *unused;
+{
+	dev_t dev;
+#ifdef DEVFS
+	int	i;
+#endif
+
+	if( ! snp_devsw_installed ) {
+		dev = makedev(CDEV_MAJOR, 0);
+		cdevsw_add(&dev,&snp_cdevsw, NULL);
+		snp_devsw_installed = 1;
+#ifdef DEVFS
+		for ( i = 0 ; i < NSNP ; i++) {
+			snp_devfs_token[i] =
+				devfs_add_devswf(&snp_cdevsw, i, DV_CHR, 0, 0, 
+						0600, "snp%d", i);
+		}
+#endif
+    	}
+}
+
+SYSINIT(snpdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,snp_drvinit,NULL)
+
+
+#endif