1#ifndef _ALPHA_CHECKSUM_H 2#define _ALPHA_CHECKSUM_H 3 4 5/* 6 * This is a version of ip_compute_csum() optimized for IP headers, 7 * which always checksum on 4 octet boundaries. 8 */ 9extern unsigned short ip_fast_csum(unsigned char * iph, unsigned int ihl); 10 11/* 12 * computes the checksum of the TCP/UDP pseudo-header 13 * returns a 16-bit checksum, already complemented 14 */ 15extern unsigned short int csum_tcpudp_magic(unsigned long saddr, 16 unsigned long daddr, 17 unsigned short len, 18 unsigned short proto, 19 unsigned int sum); 20 21unsigned int csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, 22 unsigned short len, unsigned short proto, 23 unsigned int sum); 24 25/* 26 * computes the checksum of a memory block at buff, length len, 27 * and adds in "sum" (32-bit) 28 * 29 * returns a 32-bit number suitable for feeding into itself 30 * or csum_tcpudp_magic 31 * 32 * this function must be called with even lengths, except 33 * for the last fragment, which may be odd 34 * 35 * it's best to have buff aligned on a 32-bit boundary 36 */ 37extern unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum); 38 39/* 40 * the same as csum_partial, but copies from src while it 41 * checksums 42 * 43 * here even more important to align src and dst on a 32-bit (or even 44 * better 64-bit) boundary 45 */ 46unsigned int csum_partial_copy(const char *src, char *dst, int len, unsigned int sum); 47 48/* 49 * the same as csum_partial, but copies from user space (but on the alpha 50 * we have just one address space, so this is identical to the above) 51 * 52 * this is obsolete and will go away. 53 */ 54#define csum_partial_copy_fromuser csum_partial_copy 55 56/* 57 * this is a new version of the above that records errors it finds in *errp, 58 * but continues and zeros the rest of the buffer. 59 */ 60unsigned int csum_partial_copy_from_user(const char *src, char *dst, int len, unsigned int sum, int *errp); 61 62unsigned int csum_partial_copy_nocheck(const char *src, char *dst, int len, unsigned int sum); 63 64 65/* 66 * this routine is used for miscellaneous IP-like checksums, mainly 67 * in icmp.c 68 */ 69 70extern unsigned short ip_compute_csum(unsigned char * buff, int len); 71 72/* 73 * Fold a partial checksum without adding pseudo headers 74 */ 75 76static inline unsigned short csum_fold(unsigned int sum) 77{ 78 sum = (sum & 0xffff) + (sum >> 16); 79 sum = (sum & 0xffff) + (sum >> 16); 80 return ~sum; 81} 82 83#define _HAVE_ARCH_IPV6_CSUM 84extern unsigned short int csum_ipv6_magic(struct in6_addr *saddr, 85 struct in6_addr *daddr, 86 __u32 len, 87 unsigned short proto, 88 unsigned int sum); 89 90#endif 91