1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
194 lines
5.3 KiB
C
194 lines
5.3 KiB
C
#ifndef _X86_64_CHECKSUM_H
|
|
#define _X86_64_CHECKSUM_H
|
|
|
|
/*
|
|
* Checksums for x86-64
|
|
* Copyright 2002 by Andi Kleen, SuSE Labs
|
|
* with some code from asm-i386/checksum.h
|
|
*/
|
|
|
|
#include <linux/compiler.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/byteorder.h>
|
|
|
|
/**
|
|
* csum_fold - Fold and invert a 32bit checksum.
|
|
* sum: 32bit unfolded sum
|
|
*
|
|
* Fold a 32bit running checksum to 16bit and invert it. This is usually
|
|
* the last step before putting a checksum into a packet.
|
|
* Make sure not to mix with 64bit checksums.
|
|
*/
|
|
static inline unsigned int csum_fold(unsigned int sum)
|
|
{
|
|
__asm__(
|
|
" addl %1,%0\n"
|
|
" adcl $0xffff,%0"
|
|
: "=r" (sum)
|
|
: "r" (sum << 16), "0" (sum & 0xffff0000)
|
|
);
|
|
return (~sum) >> 16;
|
|
}
|
|
|
|
/*
|
|
* This is a version of ip_compute_csum() optimized for IP headers,
|
|
* which always checksum on 4 octet boundaries.
|
|
*
|
|
* By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by
|
|
* Arnt Gulbrandsen.
|
|
*/
|
|
|
|
/**
|
|
* ip_fast_csum - Compute the IPv4 header checksum efficiently.
|
|
* iph: ipv4 header
|
|
* ihl: length of header / 4
|
|
*/
|
|
static inline unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl)
|
|
{
|
|
unsigned int sum;
|
|
|
|
asm( " movl (%1), %0\n"
|
|
" subl $4, %2\n"
|
|
" jbe 2f\n"
|
|
" addl 4(%1), %0\n"
|
|
" adcl 8(%1), %0\n"
|
|
" adcl 12(%1), %0\n"
|
|
"1: adcl 16(%1), %0\n"
|
|
" lea 4(%1), %1\n"
|
|
" decl %2\n"
|
|
" jne 1b\n"
|
|
" adcl $0, %0\n"
|
|
" movl %0, %2\n"
|
|
" shrl $16, %0\n"
|
|
" addw %w2, %w0\n"
|
|
" adcl $0, %0\n"
|
|
" notl %0\n"
|
|
"2:"
|
|
/* Since the input registers which are loaded with iph and ipl
|
|
are modified, we must also specify them as outputs, or gcc
|
|
will assume they contain their original values. */
|
|
: "=r" (sum), "=r" (iph), "=r" (ihl)
|
|
: "1" (iph), "2" (ihl)
|
|
: "memory");
|
|
return(sum);
|
|
}
|
|
|
|
/**
|
|
* csum_tcpup_nofold - Compute an IPv4 pseudo header checksum.
|
|
* @saddr: source address
|
|
* @daddr: destination address
|
|
* @len: length of packet
|
|
* @proto: ip protocol of packet
|
|
* @sum: initial sum to be added in (32bit unfolded)
|
|
*
|
|
* Returns the pseudo header checksum the input data. Result is
|
|
* 32bit unfolded.
|
|
*/
|
|
static inline unsigned long
|
|
csum_tcpudp_nofold(unsigned saddr, unsigned daddr, unsigned short len,
|
|
unsigned short proto, unsigned int sum)
|
|
{
|
|
asm(" addl %1, %0\n"
|
|
" adcl %2, %0\n"
|
|
" adcl %3, %0\n"
|
|
" adcl $0, %0\n"
|
|
: "=r" (sum)
|
|
: "g" (daddr), "g" (saddr), "g" ((ntohs(len)<<16)+proto*256), "0" (sum));
|
|
return sum;
|
|
}
|
|
|
|
|
|
/**
|
|
* csum_tcpup_magic - Compute an IPv4 pseudo header checksum.
|
|
* @saddr: source address
|
|
* @daddr: destination address
|
|
* @len: length of packet
|
|
* @proto: ip protocol of packet
|
|
* @sum: initial sum to be added in (32bit unfolded)
|
|
*
|
|
* Returns the 16bit pseudo header checksum the input data already
|
|
* complemented and ready to be filled in.
|
|
*/
|
|
static inline unsigned short int
|
|
csum_tcpudp_magic(unsigned long saddr, unsigned long daddr,
|
|
unsigned short len, unsigned short proto, unsigned int sum)
|
|
{
|
|
return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
|
|
}
|
|
|
|
/**
|
|
* csum_partial - Compute an internet checksum.
|
|
* @buff: buffer to be checksummed
|
|
* @len: length of buffer.
|
|
* @sum: initial sum to be added in (32bit unfolded)
|
|
*
|
|
* Returns the 32bit unfolded internet checksum of the buffer.
|
|
* Before filling it in it needs to be csum_fold()'ed.
|
|
* buff should be aligned to a 64bit boundary if possible.
|
|
*/
|
|
extern unsigned int csum_partial(const unsigned char *buff, unsigned len, unsigned int sum);
|
|
|
|
#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER 1
|
|
#define HAVE_CSUM_COPY_USER 1
|
|
|
|
|
|
/* Do not call this directly. Use the wrappers below */
|
|
extern unsigned long csum_partial_copy_generic(const unsigned char *src, const unsigned char *dst,
|
|
unsigned len,
|
|
unsigned sum,
|
|
int *src_err_ptr, int *dst_err_ptr);
|
|
|
|
|
|
extern unsigned int csum_partial_copy_from_user(const unsigned char __user *src, unsigned char *dst,
|
|
int len, unsigned int isum, int *errp);
|
|
extern unsigned int csum_partial_copy_to_user(const unsigned char *src, unsigned char __user *dst,
|
|
int len, unsigned int isum, int *errp);
|
|
extern unsigned int csum_partial_copy_nocheck(const unsigned char *src, unsigned char *dst, int len,
|
|
unsigned int sum);
|
|
|
|
/* Old names. To be removed. */
|
|
#define csum_and_copy_to_user csum_partial_copy_to_user
|
|
#define csum_and_copy_from_user csum_partial_copy_from_user
|
|
|
|
/**
|
|
* ip_compute_csum - Compute an 16bit IP checksum.
|
|
* @buff: buffer address.
|
|
* @len: length of buffer.
|
|
*
|
|
* Returns the 16bit folded/inverted checksum of the passed buffer.
|
|
* Ready to fill in.
|
|
*/
|
|
extern unsigned short ip_compute_csum(unsigned char * buff, int len);
|
|
|
|
/**
|
|
* csum_ipv6_magic - Compute checksum of an IPv6 pseudo header.
|
|
* @saddr: source address
|
|
* @daddr: destination address
|
|
* @len: length of packet
|
|
* @proto: protocol of packet
|
|
* @sum: initial sum (32bit unfolded) to be added in
|
|
*
|
|
* Computes an IPv6 pseudo header checksum. This sum is added the checksum
|
|
* into UDP/TCP packets and contains some link layer information.
|
|
* Returns the unfolded 32bit checksum.
|
|
*/
|
|
|
|
struct in6_addr;
|
|
|
|
#define _HAVE_ARCH_IPV6_CSUM 1
|
|
extern unsigned short
|
|
csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr,
|
|
__u32 len, unsigned short proto, unsigned int sum);
|
|
|
|
static inline unsigned add32_with_carry(unsigned a, unsigned b)
|
|
{
|
|
asm("addl %2,%0\n\t"
|
|
"adcl $0,%0"
|
|
: "=r" (a)
|
|
: "0" (a), "r" (b));
|
|
return a;
|
|
}
|
|
|
|
#endif
|
|
|