1 files changed, 52 insertions, 0 deletions
diff --git a/usr.sbin/route6d/misc/cksum.c b/usr.sbin/route6d/misc/cksum.c
new file mode 100644
index 0000000..bff7e2d
--- /dev/null
+++ b/usr.sbin/route6d/misc/cksum.c
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
+ * 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.
+ * 3. Neither the name of the project nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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 <stdio.h>
+
+unsigned short buf[BUFSIZ];
+
+main()
+{
+	int	i;
+	unsigned short *p = buf, *q = &buf[4];
+	unsigned long sum, sum2;
+
+	while (scanf("%x", &i) != EOF) {
+		*p++ = i; printf("%d ", i);
+	}
+	printf("\n");
+
+	sum = buf[2] + (buf[3] >> 8) & 0xff;
+	while (q != p)
+		sum += (*q++ & 0xffff);
+	sum2 = (sum & 0xffff) + (sum >> 16) & 0xffff;
+	printf("%x, %x\n", sum, sum2);
+}