LXR linux/arch/alpha/include/asm/checksum.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _ALPHA_CHECKSUM_H
   3#define _ALPHA_CHECKSUM_H
   4
   5#include <linux/in6.h>
   6
   7/*
   8 *      This is a version of ip_compute_csum() optimized for IP headers,
   9 *      which always checksum on 4 octet boundaries.
  10 */
  11extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
  12
  13/*
  14 * computes the checksum of the TCP/UDP pseudo-header
  15 * returns a 16-bit checksum, already complemented
  16 */
  17__sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
  18                          __u32 len, __u8 proto, __wsum sum);
  19
  20__wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
  21                          __u32 len, __u8 proto, __wsum sum);
  22
  23/*
  24 * computes the checksum of a memory block at buff, length len,
  25 * and adds in "sum" (32-bit)
  26 *
  27 * returns a 32-bit number suitable for feeding into itself
  28 * or csum_tcpudp_magic
  29 *
  30 * this function must be called with even lengths, except
  31 * for the last fragment, which may be odd
  32 *
  33 * it's best to have buff aligned on a 32-bit boundary
  34 */
  35extern __wsum csum_partial(const void *buff, int len, __wsum sum);
  36
  37/*
  38 * the same as csum_partial, but copies from src while it
  39 * checksums
  40 *
  41 * here even more important to align src and dst on a 32-bit (or even
  42 * better 64-bit) boundary
  43 */
  44#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
  45#define _HAVE_ARCH_CSUM_AND_COPY
  46__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len);
  47
  48__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
  49
  50
  51/*
  52 * this routine is used for miscellaneous IP-like checksums, mainly
  53 * in icmp.c
  54 */
  55
  56extern __sum16 ip_compute_csum(const void *buff, int len);
  57
  58/*
  59 *      Fold a partial checksum without adding pseudo headers
  60 */
  61
  62static inline __sum16 csum_fold(__wsum csum)
  63{
  64        u32 sum = (__force u32)csum;
  65        sum = (sum & 0xffff) + (sum >> 16);
  66        sum = (sum & 0xffff) + (sum >> 16);
  67        return (__force __sum16)~sum;
  68}
  69
  70#define _HAVE_ARCH_IPV6_CSUM
  71extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
  72                               const struct in6_addr *daddr,
  73                               __u32 len, __u8 proto, __wsum sum);
  74#endif
  75