freebsd-dev/sys/netipx/ipx_cksum.c
John Hay 8c7e2b93a0 Mega IPX commit.
Use the MAC address of an interface for the host part of an IPX address
and not the MAC address of the first interface for every IPX address.
This is more inline with the way others like Novell do it.
Mostly Submitted by: "Serge A. Babkin" <babkin@hq.icb.chel.su>

Take out the error messages (the ip icmp equivalent) with #ifdef IPXERRORMSGS.
This is bogus and as far as I could figure out IPX don't have anything like
it. This is a leftover from its XNS heritage. If nobody complains, I will
take it out completely in a few weeks.

Add some more ipxstat statistics counters.

Make ipxprintfs a sysctl variable and off by default.

Add IPX Netbios "routing" support. This is off by default and can be
switched on with a sysctl knob.

General code cleanup to at least use the same style throughout the IPX
code, but also be more style(9) conformant. Also make a lot of functions
static.

If I don't get any complaints I'll bring all of this over to the 2.2 tree
in a few weeks.
1997-05-10 09:58:58 +00:00

216 lines
6.5 KiB
C

/*
* Copyright (c) 1995, Mike Mitchell
* Copyright (c) 1982, 1992, 1993
* The Regents of the University of California. 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. 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, Berkeley 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.
*
* @(#)ipx_cksum.c
*
* $Id: ipx_cksum.c,v 1.5 1997/02/22 09:41:52 peter Exp $
*/
#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <net/route.h>
#include <netipx/ipx.h>
#include <netipx/ipx_var.h>
/*
* Checksum routine for Network Systems Protocol Packets (Big-Endian).
*
* This routine is very heavily used in the network
* code and should be modified for each CPU to be as fast as possible.
*/
#define ADDCARRY(x) { if ((x) > 65535) (x) -= 65535; }
#define FOLD(x) {l_util.l = (x); (x) = l_util.s[0] + l_util.s[1]; ADDCARRY(x);}
u_short
ipx_cksum(m, len)
struct mbuf *m;
int len;
{
register u_short *w;
register int sum = 0;
register int mlen = 0;
register int sum2;
union {
u_short s[2];
long l;
} l_util;
for (;m != NULL && len; m = m->m_next) {
if (m->m_len == 0)
continue;
/*
* Each trip around loop adds in
* word from one mbuf segment.
*/
w = mtod(m, u_short *);
if (mlen == -1) {
/*
* There is a byte left from the last segment;
* ones-complement add it into the checksum.
*/
#if BYTE_ORDER == BIG_ENDIAN
sum += *(u_char *)w;
#else
sum += *(u_char *)w << 8;
#endif
sum += sum;
w = (u_short *)(1 + (char *)w);
mlen = m->m_len - 1;
len--;
FOLD(sum);
} else
mlen = m->m_len;
if (len < mlen)
mlen = len;
len -= mlen;
/*
* We can do a 16 bit ones complement sum using
* 32 bit arithmetic registers for adding,
* with carries from the low added
* into the high (by normal carry-chaining)
* so long as we fold back before 16 carries have occured.
*/
if (1 & (int) w)
goto uuuuglyy;
#ifndef TINY
/* -DTINY reduces the size from 1250 to 550, but slows it down by 22% */
while ((mlen -= 32) >= 0) {
sum += w[0]; sum += sum; sum += w[1]; sum += sum;
sum += w[2]; sum += sum; sum += w[3]; sum += sum;
sum += w[4]; sum += sum; sum += w[5]; sum += sum;
sum += w[6]; sum += sum; sum += w[7]; sum += sum;
FOLD(sum);
sum += w[8]; sum += sum; sum += w[9]; sum += sum;
sum += w[10]; sum += sum; sum += w[11]; sum += sum;
sum += w[12]; sum += sum; sum += w[13]; sum += sum;
sum += w[14]; sum += sum; sum += w[15]; sum += sum;
FOLD(sum);
w += 16;
}
mlen += 32;
#endif
while ((mlen -= 8) >= 0) {
sum += w[0]; sum += sum; sum += w[1]; sum += sum;
sum += w[2]; sum += sum; sum += w[3]; sum += sum;
FOLD(sum);
w += 4;
}
mlen += 8;
while ((mlen -= 2) >= 0) {
sum += *w++; sum += sum;
}
goto commoncase;
uuuuglyy:
#if BYTE_ORDER == BIG_ENDIAN
#define ww(n) (((u_char *)w)[n + n + 1])
#define vv(n) (((u_char *)w)[n + n])
#else
#if BYTE_ORDER == LITTLE_ENDIAN
#define vv(n) (((u_char *)w)[n + n + 1])
#define ww(n) (((u_char *)w)[n + n])
#endif
#endif
sum2 = 0;
#ifndef TINY
while ((mlen -= 32) >= 0) {
sum += ww(0); sum += sum; sum += ww(1); sum += sum;
sum += ww(2); sum += sum; sum += ww(3); sum += sum;
sum += ww(4); sum += sum; sum += ww(5); sum += sum;
sum += ww(6); sum += sum; sum += ww(7); sum += sum;
FOLD(sum);
sum += ww(8); sum += sum; sum += ww(9); sum += sum;
sum += ww(10); sum += sum; sum += ww(11); sum += sum;
sum += ww(12); sum += sum; sum += ww(13); sum += sum;
sum += ww(14); sum += sum; sum += ww(15); sum += sum;
FOLD(sum);
sum2 += vv(0); sum2 += sum2; sum2 += vv(1); sum2 += sum2;
sum2 += vv(2); sum2 += sum2; sum2 += vv(3); sum2 += sum2;
sum2 += vv(4); sum2 += sum2; sum2 += vv(5); sum2 += sum2;
sum2 += vv(6); sum2 += sum2; sum2 += vv(7); sum2 += sum2;
FOLD(sum2);
sum2 += vv(8); sum2 += sum2; sum2 += vv(9); sum2 += sum2;
sum2 += vv(10); sum2 += sum2; sum2 += vv(11); sum2 += sum2;
sum2 += vv(12); sum2 += sum2; sum2 += vv(13); sum2 += sum2;
sum2 += vv(14); sum2 += sum2; sum2 += vv(15); sum2 += sum2;
FOLD(sum2);
w += 16;
}
mlen += 32;
#endif
while ((mlen -= 8) >= 0) {
sum += ww(0); sum += sum; sum += ww(1); sum += sum;
sum += ww(2); sum += sum; sum += ww(3); sum += sum;
FOLD(sum);
sum2 += vv(0); sum2 += sum2; sum2 += vv(1); sum2 += sum2;
sum2 += vv(2); sum2 += sum2; sum2 += vv(3); sum2 += sum2;
FOLD(sum2);
w += 4;
}
mlen += 8;
while ((mlen -= 2) >= 0) {
sum += ww(0); sum += sum;
sum2 += vv(0); sum2 += sum2;
w++;
}
sum += (sum2 << 8);
commoncase:
if (mlen == -1) {
#if BYTE_ORDER == BIG_ENDIAN
sum += *(u_char *)w << 8;
#else
sum += *(u_char *)w;
#endif
}
FOLD(sum);
}
if (mlen == -1) {
/* We had an odd number of bytes to sum; assume a garbage
byte of zero and clean up */
sum += sum;
FOLD(sum);
}
/*
* sum has already been kept to low sixteen bits.
* just examine result and exit.
*/
if(sum == 0xffff)
sum = 0;
return (sum);
}