1 files changed, 55 insertions, 0 deletions
diff --git a/sys/libkern/strvalid.c b/sys/libkern/strvalid.c
new file mode 100644
index 0000000..df1b071
--- /dev/null
+++ b/sys/libkern/strvalid.c
@@ -0,0 +1,55 @@
+/*-
+ * Copyright (c) 2002 Networks Associates Technologies, Inc.
+ * All rights reserved.
+ *
+ * This software was developed for the FreeBSD Project by NAI Labs,
+ * the Security Research Division of Network Associates, Inc. under
+ * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
+ * CHATS research program.
+ *
+ * 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.
+ * 3. The names of the authors may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/types.h>
+#include <sys/libkern.h>
+
+/*
+ * Return (1) if the buffer pointed to by kernel pointer 'buffer' and
+ * of length 'bufferlen' contains a valid NUL-terminated string
+ */
+int
+strvalid(const char *buffer, size_t bufferlen)
+{
+	int i;
+
+	/* Must be NUL-terminated. */
+	for (i = 0; i < bufferlen; i++)
+		if (buffer[i] == '\0')
+			return (1);
+
+	return (0);
+}