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52 * this is obsolete and will go away.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