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authorEsben Norby <norby@cvs.openbsd.org>2006-06-01 14:12:21 +0000
committerEsben Norby <norby@cvs.openbsd.org>2006-06-01 14:12:21 +0000
commit50b1cb4247102023b3d4274ecdef33ecc5ecf92d (patch)
tree3f03e69e83c764e467726916d53f06f34a5d7a0f /usr.sbin/dvmrpd/in_cksum.c
parent7acba1e80465cf8a211886130942b49523343441 (diff)
Welcome dvmrpd
started by Esben Norby some time ago by using the imsg/three process framework of ospfd. Right now it is not particularly useful, major parts are still missing but is imported to allow more people to work on it. Status: The IGMP part is mostly complete, allowing clients to join and leave groups. Election the IGMP querier of a network is also functional, only thing missing is some corner cases when going from non-querier to querier. About half of the DVMRP is functional, probes and route reports are functional. Multicast streams can be detected and the MFC can be manipulated. The RIB is not complete but operational. Not yet connected to the builds. OK claudio@
Diffstat (limited to 'usr.sbin/dvmrpd/in_cksum.c')
-rw-r--r--usr.sbin/dvmrpd/in_cksum.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/usr.sbin/dvmrpd/in_cksum.c b/usr.sbin/dvmrpd/in_cksum.c
new file mode 100644
index 00000000000..67a2145a73f
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+++ b/usr.sbin/dvmrpd/in_cksum.c
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+/* $OpenBSD: in_cksum.c,v 1.1 2006/06/01 14:12:20 norby Exp $ */
+/* $NetBSD: in_cksum.c,v 1.3 1995/04/22 13:53:48 cgd Exp $ */
+
+/*
+ * Copyright (c) 1992 Regents of the University of California.
+ * All rights reserved.
+ *
+ * This software was developed by the Computer Systems Engineering group
+ * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
+ * contributed to Berkeley.
+ *
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Lawrence Berkeley Laboratory and its contributors.
+ * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
+ *
+ * @(#) Header: in_cksum.c,v 1.1 92/09/11 01:15:55 leres Exp (LBL)
+ */
+
+#include <sys/types.h>
+
+#include "dvmrpd.h"
+#include "log.h"
+
+/*
+ * Checksum routine for Internet Protocol family headers.
+ * This routine is very heavily used in the network
+ * code and should be modified for each CPU to be as fast as possible.
+ * In particular, it should not be this one.
+ */
+u_int16_t
+in_cksum(void *p, size_t l)
+{
+ unsigned int sum = 0;
+ int len, oddbyte = 0, v = 0;
+ u_char *cp = p;
+
+ /* ensure that < 2^16 bytes being summed */
+ if (l >= (1 << 16))
+ fatalx("in_cksum: packet to big");
+ len = (int)l;
+
+ while (len > 0) {
+ if (oddbyte) {
+ sum += v + *cp++;
+ len--;
+ }
+ if (((long)cp & 1) == 0) {
+ while ((len -= 2) >= 0) {
+ sum += *(u_short *)cp;
+ cp += 2;
+ }
+ } else {
+ while ((len -= 2) >= 0) {
+ sum += *cp++ << 8;
+ sum += *cp++;
+ }
+ }
+ if ((oddbyte = len & 1) != 0)
+ v = *cp << 8;
+ }
+ if (oddbyte)
+ sum += v;
+ sum = (sum >> 16) + (sum & 0xffff); /* add in accumulated carries */
+ sum += sum >> 16; /* add potential last carry */
+ return (0xffff & ~sum);
+}