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@@ -1,172 +0,0 @@
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-/*
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- *
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- * INET An implementation of the TCP/IP protocol suite for the LINUX
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- * operating system. INET is implemented using the BSD Socket
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- * interface as the means of communication with the user level.
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- *
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- * IP/TCP/UDP checksumming routines
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- *
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- * Authors: Jorge Cwik, <jorge@laser.satlink.net>
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- * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
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- * Tom May, <ftom@netcom.com>
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- * Andreas Schwab, <schwab@issan.informatik.uni-dortmund.de>
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- * Lots of code moved from tcp.c and ip.c; see those files
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- * for more names.
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- *
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- * 03/02/96 Jes Sorensen, Andreas Schwab, Roman Hodek:
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- * Fixed some nasty bugs, causing some horrible crashes.
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- * A: At some points, the sum (%0) was used as
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- * length-counter instead of the length counter
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- * (%1). Thanks to Roman Hodek for pointing this out.
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- * B: GCC seems to mess up if one uses too many
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- * data-registers to hold input values and one tries to
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- * specify d0 and d1 as scratch registers. Letting gcc
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- * choose these registers itself solves the problem.
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- *
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- * This program is free software; you can redistribute it and/or
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- * modify it under the terms of the GNU General Public License
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- * as published by the Free Software Foundation; either version
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- * 2 of the License, or (at your option) any later version.
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- */
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-
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-/* Revised by Kenneth Albanowski for m68knommu. Basic problem: unaligned access
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- kills, so most of the assembly has to go. */
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-
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-#include <linux/module.h>
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-#include <net/checksum.h>
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-
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-#include <asm/byteorder.h>
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-
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-static inline unsigned short from32to16(unsigned long x)
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-{
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- /* add up 16-bit and 16-bit for 16+c bit */
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- x = (x & 0xffff) + (x >> 16);
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- /* add up carry.. */
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- x = (x & 0xffff) + (x >> 16);
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- return x;
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-}
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-
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-static unsigned int do_csum(const unsigned char *buff, int len)
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-{
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- int odd, count;
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- unsigned long result = 0;
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-
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- if (len <= 0)
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- goto out;
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- odd = 1 & (unsigned long) buff;
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- if (odd) {
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- result = *buff;
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- len--;
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- buff++;
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- }
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- count = len >> 1; /* nr of 16-bit words.. */
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- if (count) {
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- if (2 & (unsigned long) buff) {
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- result += *(unsigned short *) buff;
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- count--;
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- len -= 2;
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- buff += 2;
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- }
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- count >>= 1; /* nr of 32-bit words.. */
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- if (count) {
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- unsigned long carry = 0;
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- do {
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- unsigned long w = *(unsigned long *) buff;
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- count--;
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- buff += 4;
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- result += carry;
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- result += w;
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- carry = (w > result);
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- } while (count);
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- result += carry;
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- result = (result & 0xffff) + (result >> 16);
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- }
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- if (len & 2) {
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- result += *(unsigned short *) buff;
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- buff += 2;
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- }
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- }
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- if (len & 1)
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- result += (*buff << 8);
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- result = from32to16(result);
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- if (odd)
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- result = ((result >> 8) & 0xff) | ((result & 0xff) << 8);
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-out:
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- return result;
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-}
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-
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-/*
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- * This is a version of ip_compute_csum() optimized for IP headers,
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- * which always checksum on 4 octet boundaries.
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- */
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-__sum16 ip_fast_csum(const void *iph, unsigned int ihl)
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-{
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- return (__force __sum16)~do_csum(iph, ihl*4);
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-}
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-EXPORT_SYMBOL(ip_fast_csum);
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-
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-/*
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- * computes the checksum of a memory block at buff, length len,
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- * and adds in "sum" (32-bit)
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- *
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- * returns a 32-bit number suitable for feeding into itself
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- * or csum_tcpudp_magic
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- *
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- * this function must be called with even lengths, except
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- * for the last fragment, which may be odd
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- *
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- * it's best to have buff aligned on a 32-bit boundary
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- */
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-__wsum csum_partial(const void *buff, int len, __wsum wsum)
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-{
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- unsigned int sum = (__force unsigned int)wsum;
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- unsigned int result = do_csum(buff, len);
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-
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- /* add in old sum, and carry.. */
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- result += sum;
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- if (sum > result)
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- result += 1;
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- return (__force __wsum)result;
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-}
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-EXPORT_SYMBOL(csum_partial);
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-
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-/*
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- * this routine is used for miscellaneous IP-like checksums, mainly
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- * in icmp.c
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- */
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-__sum16 ip_compute_csum(const void *buff, int len)
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-{
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- return (__force __sum16)~do_csum(buff, len);
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-}
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-EXPORT_SYMBOL(ip_compute_csum);
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-
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-/*
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- * copy from fs while checksumming, otherwise like csum_partial
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- */
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-__wsum
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-csum_partial_copy_from_user(const void __user *src, void *dst, int len,
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- __wsum sum, int *csum_err)
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-{
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- int missing;
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-
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- missing = __copy_from_user(dst, src, len);
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- if (missing) {
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- memset(dst + len - missing, 0, missing);
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- *csum_err = -EFAULT;
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- } else
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- *csum_err = 0;
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-
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- return csum_partial(dst, len, sum);
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-}
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-EXPORT_SYMBOL(csum_partial_copy_from_user);
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-
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-/*
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- * copy from ds while checksumming, otherwise like csum_partial
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- */
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-__wsum
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-csum_partial_copy(const void *src, void *dst, int len, __wsum sum)
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-{
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- memcpy(dst, src, len);
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- return csum_partial(dst, len, sum);
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-}
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-EXPORT_SYMBOL(csum_partial_copy);
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