a4f89fb7c0
* sanitize prototypes, annotate * usual ntohs->shift Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
135 lines
3.8 KiB
C
135 lines
3.8 KiB
C
/* Copyright 2002,2003 Andi Kleen, SuSE Labs.
|
|
* Subject to the GNU Public License v.2
|
|
*
|
|
* Wrappers of assembly checksum functions for x86-64.
|
|
*/
|
|
|
|
#include <asm/checksum.h>
|
|
#include <linux/module.h>
|
|
|
|
/**
|
|
* csum_partial_copy_from_user - Copy and checksum from user space.
|
|
* @src: source address (user space)
|
|
* @dst: destination address
|
|
* @len: number of bytes to be copied.
|
|
* @isum: initial sum that is added into the result (32bit unfolded)
|
|
* @errp: set to -EFAULT for an bad source address.
|
|
*
|
|
* Returns an 32bit unfolded checksum of the buffer.
|
|
* src and dst are best aligned to 64bits.
|
|
*/
|
|
__wsum
|
|
csum_partial_copy_from_user(const void __user *src, void *dst,
|
|
int len, __wsum isum, int *errp)
|
|
{
|
|
might_sleep();
|
|
*errp = 0;
|
|
if (likely(access_ok(VERIFY_READ,src, len))) {
|
|
/* Why 6, not 7? To handle odd addresses aligned we
|
|
would need to do considerable complications to fix the
|
|
checksum which is defined as an 16bit accumulator. The
|
|
fix alignment code is primarily for performance
|
|
compatibility with 32bit and that will handle odd
|
|
addresses slowly too. */
|
|
if (unlikely((unsigned long)src & 6)) {
|
|
while (((unsigned long)src & 6) && len >= 2) {
|
|
__u16 val16;
|
|
*errp = __get_user(val16, (const __u16 __user *)src);
|
|
if (*errp)
|
|
return isum;
|
|
*(__u16 *)dst = val16;
|
|
isum = (__force __wsum)add32_with_carry(
|
|
(__force unsigned)isum, val16);
|
|
src += 2;
|
|
dst += 2;
|
|
len -= 2;
|
|
}
|
|
}
|
|
isum = csum_partial_copy_generic((__force const void *)src,
|
|
dst, len, isum, errp, NULL);
|
|
if (likely(*errp == 0))
|
|
return isum;
|
|
}
|
|
*errp = -EFAULT;
|
|
memset(dst,0,len);
|
|
return isum;
|
|
}
|
|
|
|
EXPORT_SYMBOL(csum_partial_copy_from_user);
|
|
|
|
/**
|
|
* csum_partial_copy_to_user - Copy and checksum to user space.
|
|
* @src: source address
|
|
* @dst: destination address (user space)
|
|
* @len: number of bytes to be copied.
|
|
* @isum: initial sum that is added into the result (32bit unfolded)
|
|
* @errp: set to -EFAULT for an bad destination address.
|
|
*
|
|
* Returns an 32bit unfolded checksum of the buffer.
|
|
* src and dst are best aligned to 64bits.
|
|
*/
|
|
__wsum
|
|
csum_partial_copy_to_user(const void *src, void __user *dst,
|
|
int len, __wsum isum, int *errp)
|
|
{
|
|
might_sleep();
|
|
if (unlikely(!access_ok(VERIFY_WRITE, dst, len))) {
|
|
*errp = -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
if (unlikely((unsigned long)dst & 6)) {
|
|
while (((unsigned long)dst & 6) && len >= 2) {
|
|
__u16 val16 = *(__u16 *)src;
|
|
isum = (__force __wsum)add32_with_carry(
|
|
(__force unsigned)isum, val16);
|
|
*errp = __put_user(val16, (__u16 __user *)dst);
|
|
if (*errp)
|
|
return isum;
|
|
src += 2;
|
|
dst += 2;
|
|
len -= 2;
|
|
}
|
|
}
|
|
|
|
*errp = 0;
|
|
return csum_partial_copy_generic(src, (void __force *)dst,len,isum,NULL,errp);
|
|
}
|
|
|
|
EXPORT_SYMBOL(csum_partial_copy_to_user);
|
|
|
|
/**
|
|
* csum_partial_copy_nocheck - Copy and checksum.
|
|
* @src: source address
|
|
* @dst: destination address
|
|
* @len: number of bytes to be copied.
|
|
* @isum: initial sum that is added into the result (32bit unfolded)
|
|
*
|
|
* Returns an 32bit unfolded checksum of the buffer.
|
|
*/
|
|
__wsum
|
|
csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
|
|
{
|
|
return csum_partial_copy_generic(src,dst,len,sum,NULL,NULL);
|
|
}
|
|
EXPORT_SYMBOL(csum_partial_copy_nocheck);
|
|
|
|
__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
|
|
const struct in6_addr *daddr,
|
|
__u32 len, unsigned short proto, __wsum sum)
|
|
{
|
|
__u64 rest, sum64;
|
|
|
|
rest = (__force __u64)htonl(len) + (__force __u64)htons(proto) +
|
|
(__force __u64)sum;
|
|
asm(" addq (%[saddr]),%[sum]\n"
|
|
" adcq 8(%[saddr]),%[sum]\n"
|
|
" adcq (%[daddr]),%[sum]\n"
|
|
" adcq 8(%[daddr]),%[sum]\n"
|
|
" adcq $0,%[sum]\n"
|
|
: [sum] "=r" (sum64)
|
|
: "[sum]" (rest),[saddr] "r" (saddr), [daddr] "r" (daddr));
|
|
return csum_fold((__force __wsum)add32_with_carry(sum64 & 0xffffffff, sum64>>32));
|
|
}
|
|
|
|
EXPORT_SYMBOL(csum_ipv6_magic);
|