1 files changed, 398 insertions, 0 deletions
diff --git a/usr/src/uts/common/fs/dev/sdev_ptsops.c b/usr/src/uts/common/fs/dev/sdev_ptsops.c
new file mode 100644
index 0000000000..7ec53cf417
--- /dev/null
+++ b/usr/src/uts/common/fs/dev/sdev_ptsops.c
@@ -0,0 +1,398 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+/*
+ * vnode ops for the /dev/pts directory
+ *	The lookup is based on the internal pty table. We also
+ *	override readdir in order to delete pts nodes no longer
+ *	in use.
+ */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/sysmacros.h>
+#include <sys/sunndi.h>
+#include <fs/fs_subr.h>
+#include <sys/fs/dv_node.h>
+#include <sys/fs/sdev_impl.h>
+#include <sys/policy.h>
+#include <sys/ptms.h>
+#include <sys/stat.h>
+
+#define	DEVPTS_UID_DEFAULT	0
+#define	DEVPTS_GID_DEFAULT	3
+#define	DEVPTS_DEVMODE_DEFAULT	(0620)
+
+#define	isdigit(ch)	((ch) >= '0' && (ch) <= '9')
+
+static vattr_t devpts_vattr = {
+	AT_TYPE|AT_MODE|AT_UID|AT_GID,		/* va_mask */
+	VCHR,					/* va_type */
+	S_IFCHR | DEVPTS_DEVMODE_DEFAULT,	/* va_mode */
+	DEVPTS_UID_DEFAULT,			/* va_uid */
+	DEVPTS_GID_DEFAULT,			/* va_gid */
+	0					/* 0 hereafter */
+};
+
+struct vnodeops		*devpts_vnodeops;
+
+struct vnodeops *
+devpts_getvnodeops(void)
+{
+	return (devpts_vnodeops);
+}
+
+/*
+ * Convert string to minor number. Some care must be taken
+ * as we are processing user input. Catch cases like
+ * /dev/pts/4foo and /dev/pts/-1
+ */
+static int
+devpts_strtol(const char *nm, minor_t *mp)
+{
+	long uminor = 0;
+	char *endptr = NULL;
+
+	if (nm == NULL || !isdigit(*nm))
+		return (EINVAL);
+
+	*mp = 0;
+	if (ddi_strtol(nm, &endptr, 10, &uminor) != 0 ||
+	    *endptr != '\0' || uminor < 0) {
+		return (EINVAL);
+	}
+
+	*mp = uminor;
+	return (0);
+}
+
+/*
+ * Check if a pts sdev_node is still valid - i.e. it represents a current pty.
+ * This serves two purposes
+ *	- only valid pts nodes are returned during lookup() and readdir().
+ *	- since pts sdev_nodes are not actively destroyed when a pty goes
+ *	  away, we use the validator to do deferred cleanup i.e. when such
+ *	  nodes are encountered during subsequent lookup() and readdir().
+ */
+/*ARGSUSED*/
+int
+devpts_validate(struct sdev_node *dv)
+{
+	minor_t min;
+	uid_t uid;
+	gid_t gid;
+	timestruc_t now;
+	char *nm = dv->sdev_name;
+
+	ASSERT(!(dv->sdev_flags & SDEV_STALE));
+	ASSERT(dv->sdev_state == SDEV_READY);
+
+	/* validate only READY nodes */
+	if (dv->sdev_state != SDEV_READY) {
+		sdcmn_err(("dev fs: skipping: node not ready %s(%p)",
+		    nm, (void *)dv));
+		return (SDEV_VTOR_SKIP);
+	}
+
+	if (devpts_strtol(nm, &min) != 0) {
+		sdcmn_err7(("devpts_validate: not a valid minor: %s\n", nm));
+		return (SDEV_VTOR_INVALID);
+	}
+
+	/*
+	 * Check if pts driver is attached
+	 */
+	if (ptms_slave_attached() == (major_t)-1) {
+		sdcmn_err7(("devpts_validate: slave not attached\n"));
+		return (SDEV_VTOR_INVALID);
+	}
+
+	if (ptms_minor_valid(min, &uid, &gid) == 0) {
+		if (ptms_minor_exists(min)) {
+			sdcmn_err7(("devpts_validate: valid in different zone "
+			    "%s\n", nm));
+			return (SDEV_VTOR_SKIP);
+		} else {
+			sdcmn_err7(("devpts_validate: %s not valid pty\n",
+			    nm));
+			return (SDEV_VTOR_INVALID);
+		}
+	}
+
+	ASSERT(dv->sdev_attr);
+	if (dv->sdev_attr->va_uid != uid || dv->sdev_attr->va_gid != gid) {
+		ASSERT(uid >= 0);
+		ASSERT(gid >= 0);
+		dv->sdev_attr->va_uid = uid;
+		dv->sdev_attr->va_gid = gid;
+		gethrestime(&now);
+		dv->sdev_attr->va_atime = now;
+		dv->sdev_attr->va_mtime = now;
+		dv->sdev_attr->va_ctime = now;
+		sdcmn_err7(("devpts_validate: update uid/gid/times%s\n", nm));
+	}
+
+	return (SDEV_VTOR_VALID);
+}
+
+/*
+ * This callback is invoked from devname_lookup_func() to create
+ * a pts entry when the node is not found in the cache.
+ */
+/*ARGSUSED*/
+static int
+devpts_create_rvp(struct sdev_node *ddv, char *nm,
+    void **arg, cred_t *cred, void *whatever, char *whichever)
+{
+	minor_t min;
+	major_t maj;
+	uid_t uid;
+	gid_t gid;
+	timestruc_t now;
+	struct vattr *vap = (struct vattr *)arg;
+
+	if (devpts_strtol(nm, &min) != 0) {
+		sdcmn_err7(("devpts_create_rvp: not a valid minor: %s\n", nm));
+		return (-1);
+	}
+
+	/*
+	 * Check if pts driver is attached and if it is
+	 * get the major number.
+	 */
+	maj = ptms_slave_attached();
+	if (maj == (major_t)-1) {
+		sdcmn_err7(("devpts_create_rvp: slave not attached\n"));
+		return (-1);
+	}
+
+	/*
+	 * Only allow creation of ptys allocated to our zone
+	 */
+	if (!ptms_minor_valid(min, &uid, &gid)) {
+		sdcmn_err7(("devpts_create_rvp: %s not valid pty"
+		    "or not valid in this zone\n", nm));
+		return (-1);
+	}
+
+
+	/*
+	 * This is a valid pty (at least at this point in time).
+	 * Create the node by setting the attribute. The rest
+	 * is taken care of by devname_lookup_func().
+	 */
+	*vap = devpts_vattr;
+	vap->va_rdev = makedevice(maj, min);
+	ASSERT(uid >= 0);
+	ASSERT(gid >= 0);
+	vap->va_uid = uid;
+	vap->va_gid = gid;
+	gethrestime(&now);
+	vap->va_atime = now;
+	vap->va_mtime = now;
+	vap->va_ctime = now;
+
+	return (0);
+}
+
+/*
+ * Clean pts sdev_nodes that are no longer valid.
+ */
+static void
+devpts_prunedir(struct sdev_node *ddv)
+{
+	struct vnode *vp;
+	struct sdev_node *dv, *next = NULL;
+	int (*vtor)(struct sdev_node *) = NULL;
+
+	ASSERT(ddv->sdev_flags & SDEV_VTOR);
+
+	vtor = (int (*)(struct sdev_node *))sdev_get_vtor(ddv);
+	ASSERT(vtor);
+
+	if (rw_tryupgrade(&ddv->sdev_contents) == NULL) {
+		rw_exit(&ddv->sdev_contents);
+		rw_enter(&ddv->sdev_contents, RW_WRITER);
+	}
+
+	for (dv = ddv->sdev_dot; dv; dv = next) {
+		next = dv->sdev_next;
+
+		/* skip stale nodes */
+		if (dv->sdev_flags & SDEV_STALE)
+			continue;
+
+		/* validate and prune only ready nodes */
+		if (dv->sdev_state != SDEV_READY)
+			continue;
+
+		switch (vtor(dv)) {
+		case SDEV_VTOR_VALID:
+		case SDEV_VTOR_SKIP:
+			continue;
+		case SDEV_VTOR_INVALID:
+			sdcmn_err7(("prunedir: destroy invalid "
+			    "node: %s(%p)\n", dv->sdev_name, (void *)dv));
+			break;
+		}
+		vp = SDEVTOV(dv);
+		if (vp->v_count > 0)
+			continue;
+		SDEV_HOLD(dv);
+		/* remove the cache node */
+		(void) sdev_cache_update(ddv, &dv, dv->sdev_name,
+		    SDEV_CACHE_DELETE);
+	}
+	rw_downgrade(&ddv->sdev_contents);
+}
+
+/*
+ * Lookup for /dev/pts directory
+ *	If the entry does not exist, the devpts_create_rvp() callback
+ *	is invoked to create it. Nodes do not persist across reboot.
+ */
+/*ARGSUSED3*/
+static int
+devpts_lookup(struct vnode *dvp, char *nm, struct vnode **vpp,
+    struct pathname *pnp, int flags, struct vnode *rdir, struct cred *cred)
+{
+	struct sdev_node *sdvp = VTOSDEV(dvp);
+	struct sdev_node *dv;
+	int error;
+
+	error = devname_lookup_func(sdvp, nm, vpp, cred, devpts_create_rvp,
+	    SDEV_VATTR);
+
+	if (error == 0) {
+		switch ((*vpp)->v_type) {
+		case VCHR:
+			dv = VTOSDEV(VTOS(*vpp)->s_realvp);
+			break;
+		case VDIR:
+			dv = VTOSDEV(*vpp);
+			break;
+		default:
+			cmn_err(CE_PANIC, "devpts_lookup: Unsupported node "
+			    "type: %p: %d", (void *)(*vpp), (*vpp)->v_type);
+			break;
+		}
+		ASSERT(SDEV_HELD(dv));
+	}
+
+	return (error);
+}
+
+/*
+ * We allow create to find existing nodes
+ *	- if the node doesn't exist - EROFS
+ *	- creating an existing dir read-only succeeds, otherwise EISDIR
+ *	- exclusive creates fail - EEXIST
+ */
+/*ARGSUSED2*/
+static int
+devpts_create(struct vnode *dvp, char *nm, struct vattr *vap, vcexcl_t excl,
+    int mode, struct vnode **vpp, struct cred *cred, int flag)
+{
+	int error;
+	struct vnode *vp;
+
+	*vpp = NULL;
+
+	error = devpts_lookup(dvp, nm, &vp, NULL, 0, NULL, cred);
+	if (error == 0) {
+		if (excl == EXCL)
+			error = EEXIST;
+		else if (vp->v_type == VDIR && (mode & VWRITE))
+			error = EISDIR;
+		else
+			error = VOP_ACCESS(vp, mode, 0, cred);
+
+		if (error) {
+			VN_RELE(vp);
+		} else
+			*vpp = vp;
+	} else if (error == ENOENT) {
+		error = EROFS;
+	}
+
+	return (error);
+}
+
+/*
+ * Display all instantiated pts (slave) device nodes.
+ * A /dev/pts entry will be created only after the first lookup of the slave
+ * device succeeds.
+ */
+static int
+devpts_readdir(struct vnode *dvp, struct uio *uiop, struct cred *cred,
+    int *eofp)
+{
+	struct sdev_node *sdvp = VTOSDEV(dvp);
+	if (uiop->uio_offset == 0) {
+		devpts_prunedir(sdvp);
+	}
+
+	return (devname_readdir_func(dvp, uiop, cred, eofp, 0));
+}
+
+
+static int
+devpts_set_id(struct sdev_node *dv, struct vattr *vap, int protocol)
+{
+	ASSERT((protocol & AT_UID) || (protocol & AT_GID));
+	ptms_set_owner(getminor(SDEVTOV(dv)->v_rdev),
+	    vap->va_uid, vap->va_gid);
+	return (0);
+
+}
+
+static int
+devpts_setattr(struct vnode *vp, struct vattr *vap, int flags,
+    struct cred *cred)
+{
+	ASSERT((vp->v_type == VCHR) || (vp->v_type == VDIR));
+	return (devname_setattr_func(vp, vap, flags, cred,
+		    devpts_set_id, AT_UID|AT_GID));
+}
+
+/*
+ * We override lookup and readdir to build entries based on the
+ * in kernel pty table. Also override setattr/setsecattr to
+ * avoid persisting permissions.
+ */
+const fs_operation_def_t devpts_vnodeops_tbl[] = {
+	VOPNAME_READDIR, devpts_readdir,
+	VOPNAME_LOOKUP, devpts_lookup,
+	VOPNAME_CREATE, devpts_create,
+	VOPNAME_SETATTR, devpts_setattr,
+	VOPNAME_REMOVE, fs_nosys,
+	VOPNAME_MKDIR, fs_nosys,
+	VOPNAME_RMDIR, fs_nosys,
+	VOPNAME_SYMLINK, fs_nosys,
+	VOPNAME_SETSECATTR, fs_nosys,
+	NULL, NULL
+};