mirror of
https://github.com/fail0verflow/switch-coreboot.git
synced 2025-05-04 01:39:18 -04:00
bea6044faa
* include cleanup. We don't provide stdint.h, so use arch/types.h instead. * drop some unused variables * fix comment style in some headers to match the template * Fix the loglevel of some debugging output. Signed-off-by: Stefan Reinauer <stepan@coresystems.de> Acked-by: Uwe Hermann <uwe@hermann-uwe.de> git-svn-id: svn://coreboot.org/repository/LinuxBIOSv3@275 f3766cd6-281f-0410-b1cd-43a5c92072e9
104 lines
2.5 KiB
C
104 lines
2.5 KiB
C
/*
|
|
* This file is part of the LinuxBIOS project.
|
|
*
|
|
* It was taken from kexec-tools 1.101.
|
|
*
|
|
* Copyright (C) 2003,2004 Eric Biederman <ebiederm@xmission.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; version 2 of the License.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include <arch/types.h>
|
|
#include <ip_checksum.h>
|
|
#include <string.h>
|
|
|
|
unsigned long compute_ip_checksum(void *addr, unsigned long length)
|
|
{
|
|
u16 *ptr;
|
|
unsigned long sum;
|
|
unsigned long len;
|
|
unsigned long laddr;
|
|
/* compute an ip style checksum */
|
|
laddr = (unsigned long )addr;
|
|
sum = 0;
|
|
if (laddr & 1) {
|
|
u16 buffer;
|
|
unsigned char *ptr;
|
|
/* copy the first byte into a 2 byte buffer.
|
|
* This way automatically handles the endian question
|
|
* of which byte (low or high) the last byte goes in.
|
|
*/
|
|
buffer = 0;
|
|
ptr = addr;
|
|
memcpy(&buffer, ptr, 1);
|
|
sum += buffer;
|
|
if (sum > 0xFFFF)
|
|
sum -= 0xFFFF;
|
|
length -= 1;
|
|
addr = ptr +1;
|
|
|
|
}
|
|
len = length >> 1;
|
|
ptr = addr;
|
|
while (len--) {
|
|
sum += *(ptr++);
|
|
if (sum > 0xFFFF)
|
|
sum -= 0xFFFF;
|
|
}
|
|
addr = ptr;
|
|
if (length & 1) {
|
|
u16 buffer;
|
|
unsigned char *ptr;
|
|
/* copy the last byte into a 2 byte buffer.
|
|
* This way automatically handles the endian question
|
|
* of which byte (low or high) the last byte goes in.
|
|
*/
|
|
buffer = 0;
|
|
ptr = addr;
|
|
memcpy(&buffer, ptr, 1);
|
|
sum += buffer;
|
|
if (sum > 0xFFFF)
|
|
sum -= 0xFFFF;
|
|
}
|
|
return (~sum) & 0xFFFF;
|
|
|
|
}
|
|
|
|
unsigned long add_ip_checksums(unsigned long offset, unsigned long sum, unsigned long new)
|
|
{
|
|
unsigned long checksum;
|
|
sum = ~sum & 0xFFFF;
|
|
new = ~new & 0xFFFF;
|
|
if (offset & 1) {
|
|
/* byte swap the sum if it came from an odd offset
|
|
* since the computation is endian independant this
|
|
* works.
|
|
*/
|
|
new = ((new >> 8) & 0xff) | ((new << 8) & 0xff00);
|
|
}
|
|
checksum = sum + new;
|
|
if (checksum > 0xFFFF) {
|
|
checksum -= 0xFFFF;
|
|
}
|
|
return (~checksum) & 0xFFFF;
|
|
}
|
|
|
|
unsigned long negate_ip_checksum(unsigned long sum)
|
|
{
|
|
sum = ~sum & 0xFFFF;
|
|
|
|
sum = 0xFFFF - sum;
|
|
|
|
return ~sum & 0xFFFF;
|
|
}
|