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 */ 11 extern __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 */ 35 extern __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 __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp); 46 47 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum); 48 49 50 /* 51 * this routine is used for miscellaneous IP-like checksums, mainly 52 * in icmp.c 53 */ 54 55 extern __sum16 ip_compute_csum(const void *buff, int len); 56 57 /* 58 * Fold a partial checksum without adding pseudo headers 59 */ 60 61 static inline __sum16 csum_fold(__wsum csum) 62 { 63 u32 sum = (__force u32)csum; 64 sum = (sum & 0xffff) + (sum >> 16); 65 sum = (sum & 0xffff) + (sum >> 16); 66 return (__force __sum16)~sum; 67 } 68 69 #define _HAVE_ARCH_IPV6_CSUM 70 extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 71 const struct in6_addr *daddr, 72 __u32 len, __u8 proto, __wsum sum); 73 #endif 74