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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /include/asm-generic/checksum.h | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/asm-generic/checksum.h')
-rw-r--r-- | include/asm-generic/checksum.h | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/include/asm-generic/checksum.h b/include/asm-generic/checksum.h new file mode 100644 index 000000000..34785c0f5 --- /dev/null +++ b/include/asm-generic/checksum.h @@ -0,0 +1,88 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_CHECKSUM_H +#define __ASM_GENERIC_CHECKSUM_H + +/* + * computes the checksum of a memory block at buff, length len, + * and adds in "sum" (32-bit) + * + * returns a 32-bit number suitable for feeding into itself + * or csum_tcpudp_magic + * + * this function must be called with even lengths, except + * for the last fragment, which may be odd + * + * it's best to have buff aligned on a 32-bit boundary + */ +extern __wsum csum_partial(const void *buff, int len, __wsum sum); + +/* + * the same as csum_partial, but copies from src while it + * checksums + * + * here even more important to align src and dst on a 32-bit (or even + * better 64-bit) boundary + */ +extern __wsum csum_partial_copy(const void *src, void *dst, int len, __wsum sum); + +/* + * the same as csum_partial_copy, but copies from user space. + * + * here even more important to align src and dst on a 32-bit (or even + * better 64-bit) boundary + */ +extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, + int len, __wsum sum, int *csum_err); + +#ifndef csum_partial_copy_nocheck +#define csum_partial_copy_nocheck(src, dst, len, sum) \ + csum_partial_copy((src), (dst), (len), (sum)) +#endif + +#ifndef ip_fast_csum +/* + * This is a version of ip_compute_csum() optimized for IP headers, + * which always checksum on 4 octet boundaries. + */ +extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); +#endif + +#ifndef csum_fold +/* + * Fold a partial checksum + */ +static inline __sum16 csum_fold(__wsum csum) +{ + u32 sum = (__force u32)csum; + sum = (sum & 0xffff) + (sum >> 16); + sum = (sum & 0xffff) + (sum >> 16); + return (__force __sum16)~sum; +} +#endif + +#ifndef csum_tcpudp_nofold +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented + */ +extern __wsum +csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len, + __u8 proto, __wsum sum); +#endif + +#ifndef csum_tcpudp_magic +static inline __sum16 +csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len, + __u8 proto, __wsum sum) +{ + return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); +} +#endif + +/* + * this routine is used for miscellaneous IP-like checksums, mainly + * in icmp.c + */ +extern __sum16 ip_compute_csum(const void *buff, int len); + +#endif /* __ASM_GENERIC_CHECKSUM_H */ |