aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-sparc64/checksum.h
blob: dc8bed246fc982da713a3fcb74434a8eb9c84888 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
/* $Id: checksum.h,v 1.19 2002/02/09 19:49:31 davem Exp $ */
#ifndef __SPARC64_CHECKSUM_H
#define __SPARC64_CHECKSUM_H

/*  checksum.h:  IP/UDP/TCP checksum routines on the V9.
 *
 *  Copyright(C) 1995 Linus Torvalds
 *  Copyright(C) 1995 Miguel de Icaza
 *  Copyright(C) 1996 David S. Miller
 *  Copyright(C) 1996 Eddie C. Dost
 *  Copyright(C) 1997 Jakub Jelinek
 *
 * derived from:
 *	Alpha checksum c-code
 *      ix86 inline assembly
 *      RFC1071 Computing the Internet Checksum
 */

#include <linux/in6.h>
#include <asm/uaccess.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 unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum);

/* the same as csum_partial, but copies from user space while it
 * checksums
 *
 * here even more important to align src and dst on a 32-bit (or even
 * better 64-bit) boundary
 */
extern unsigned int csum_partial_copy_nocheck(const unsigned char *src,
					      unsigned char *dst,
					      int len, unsigned int sum);

extern long __csum_partial_copy_from_user(const unsigned char __user *src,
					  unsigned char *dst, int len,
					  unsigned int sum);

static inline unsigned int
csum_partial_copy_from_user(const unsigned char __user *src,
			    unsigned char *dst, int len,
			    unsigned int sum, int *err)
{
	long ret = __csum_partial_copy_from_user(src, dst, len, sum);
	if (ret < 0)
		*err = -EFAULT;
	return (unsigned int) ret;
}

/* 
 *	Copy and checksum to user
 */
#define HAVE_CSUM_COPY_USER
extern long __csum_partial_copy_to_user(const unsigned char *src,
					unsigned char __user *dst, int len,
					  unsigned int sum);

static inline unsigned int
csum_and_copy_to_user(const unsigned char *src,
		      unsigned char __user *dst, int len,
		      unsigned int sum, int *err)
{
	long ret = __csum_partial_copy_to_user(src, dst, len, sum);
	if (ret < 0)
		*err = -EFAULT;
	return (unsigned int) ret;
}

/* ihl is always 5 or greater, almost always is 5, and iph is word aligned
 * the majority of the time.
 */
extern unsigned short ip_fast_csum(__const__ unsigned char *iph,
				   unsigned int ihl);

/* Fold a partial checksum without adding pseudo headers. */
static inline unsigned short csum_fold(unsigned int sum)
{
	unsigned int tmp;

	__asm__ __volatile__(
"	addcc		%0, %1, %1\n"
"	srl		%1, 16, %1\n"
"	addc		%1, %%g0, %1\n"
"	xnor		%%g0, %1, %0\n"
	: "=&r" (sum), "=r" (tmp)
	: "0" (sum), "1" (sum<<16)
	: "cc");
	return (sum & 0xffff);
}

static inline unsigned long csum_tcpudp_nofold(unsigned long saddr,
					       unsigned long daddr,
					       unsigned int len,
					       unsigned short proto,
					       unsigned int sum)
{
	__asm__ __volatile__(
"	addcc		%1, %0, %0\n"
"	addccc		%2, %0, %0\n"
"	addccc		%3, %0, %0\n"
"	addc		%0, %%g0, %0\n"
	: "=r" (sum), "=r" (saddr)
	: "r" (daddr), "r" ((proto<<16)+len), "0" (sum), "1" (saddr)
	: "cc");
	return sum;
}

/*
 * computes the checksum of the TCP/UDP pseudo-header
 * returns a 16-bit checksum, already complemented
 */
static inline unsigned short int csum_tcpudp_magic(unsigned long saddr,
						   unsigned long daddr,
						   unsigned short len,
						   unsigned short proto,
						   unsigned int sum) 
{
	return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
}

#define _HAVE_ARCH_IPV6_CSUM

static inline unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
						 struct in6_addr *daddr,
						 __u32 len,
						 unsigned short proto,
						 unsigned int sum) 
{
	__asm__ __volatile__ (
"	addcc		%3, %4, %%g7\n"
"	addccc		%5, %%g7, %%g7\n"
"	lduw		[%2 + 0x0c], %%g2\n"
"	lduw		[%2 + 0x08], %%g3\n"
"	addccc		%%g2, %%g7, %%g7\n"
"	lduw		[%2 + 0x04], %%g2\n"
"	addccc		%%g3, %%g7, %%g7\n"
"	lduw		[%2 + 0x00], %%g3\n"
"	addccc		%%g2, %%g7, %%g7\n"
"	lduw		[%1 + 0x0c], %%g2\n"
"	addccc		%%g3, %%g7, %%g7\n"
"	lduw		[%1 + 0x08], %%g3\n"
"	addccc		%%g2, %%g7, %%g7\n"
"	lduw		[%1 + 0x04], %%g2\n"
"	addccc		%%g3, %%g7, %%g7\n"
"	lduw		[%1 + 0x00], %%g3\n"
"	addccc		%%g2, %%g7, %%g7\n"
"	addccc		%%g3, %%g7, %0\n"
"	addc		0, %0, %0\n"
	: "=&r" (sum)
	: "r" (saddr), "r" (daddr), "r"(htonl(len)),
	  "r"(htonl(proto)), "r"(sum)
	: "g2", "g3", "g7", "cc");

	return csum_fold(sum);
}

/* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
static inline unsigned short ip_compute_csum(unsigned char * buff, int len)
{
	return csum_fold(csum_partial(buff, len, 0));
}

#endif /* !(__SPARC64_CHECKSUM_H) */