Introduce the DEVFS "rule" subsystem. DEVFS rules permit the

administrator to define certain properties of new devfs nodes before
they become visible to the userland.  Both static (e.g., /dev/speaker)
and dynamic (e.g., /dev/bpf*, some removable devices) nodes are
supported.  Each DEVFS mount may have a different ruleset assigned to
it, permitting different policies to be implemented for things like
jails.

Approved by:	phk

1 files changed, 140 insertions, 0 deletions

diff --git a/sbin/devfs/devfs.c b/sbin/devfs/devfs.c
new file mode 100644
index 0000000..4622bb9
--- /dev/null
+++ b/sbin/devfs/devfs.c
@@ -0,0 +1,140 @@
+/*-
+ * Copyright (c) 2002 Dima Dorfman.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * DEVFS control.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+
+#include <err.h>
+#include <fcntl.h>
+#include <paths.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "extern.h"
+
+int mpfd;
+
+static ctbl_t ctbl_main = {
+	{ "rule",		rule_main },
+	{ "ruleset",		ruleset_main },
+	{ NULL,			NULL }
+};
+
+int
+main(int ac, char **av)
+{
+	const char *mountpt;
+	struct cmd *c;
+	char ch;
+
+	mountpt = NULL;
+	while ((ch = getopt(ac, av, "m:")) != -1)
+		switch (ch) {
+		case 'm':
+			mountpt = optarg;
+			break;
+		default:
+			usage();
+		}
+	ac -= optind;
+	av += optind;
+	if (ac < 1)
+		usage();
+
+	if (mountpt == NULL)
+		mountpt = _PATH_DEV;
+	mpfd = open(mountpt, O_RDONLY);
+	if (mpfd == -1)
+		err(1, "open: %s", mountpt);
+
+	for (c = ctbl_main; c->name != NULL; ++c)
+		if (strcmp(c->name, av[0]) == 0)
+			exit((*c->handler)(ac, av));
+	errx(1, "unknown command: %s", av[0]);
+}
+
+/*
+ * Convert an integer to a "number" (ruleset numbers and rule numbers
+ * are 16-bit).  If the conversion is successful, num contains the
+ * integer representation of s and 1 is returned; otherwise, 0 is
+ * returned and num is unchanged.
+ */
+int
+atonum(const char *s, uint16_t *num)
+{
+	unsigned long ul;
+	char *cp;
+
+	ul = strtoul(s, &cp, 10);
+	if (ul > UINT16_MAX || *cp != '\0')
+		return (0);
+	*num = (uint16_t)ul;
+	return (1);
+}
+
+/*
+ * Convert user input in ASCII to an integer.
+ */
+int
+eatoi(const char *s)
+{
+	char *cp;
+	long l;
+
+	l = strtol(s, &cp, 10);
+	if (l > INT_MAX || *cp != '\0')
+		errx(1, "error converting to integer: %s", s);
+	return ((int)l);
+}	
+
+/*
+ * As atonum(), but the result of failure is death.
+ */
+uint16_t
+eatonum(const char *s)
+{
+	uint16_t num;
+
+	if (!atonum(s, &num))
+		errx(1, "error converting to number: %s", s); /* XXX clarify */
+	return (num);
+}	
+
+void
+usage(void)
+{
+
+	fprintf(stderr, "usage: devfs rule|ruleset arguments\n");
+	exit(1);
+}