Root/
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
3 | * operating system. INET is implemented using the BSD Socket |
4 | * interface as the means of communication with the user level. |
5 | * |
6 | * Checksumming functions for IP, TCP, UDP and so on |
7 | * |
8 | * Authors: Jorge Cwik, <jorge@laser.satlink.net> |
9 | * Arnt Gulbrandsen, <agulbra@nvg.unit.no> |
10 | * Borrows very liberally from tcp.c and ip.c, see those |
11 | * files for more names. |
12 | * |
13 | * This program is free software; you can redistribute it and/or |
14 | * modify it under the terms of the GNU General Public License |
15 | * as published by the Free Software Foundation; either version |
16 | * 2 of the License, or (at your option) any later version. |
17 | */ |
18 | |
19 | #ifndef _CHECKSUM_H |
20 | #define _CHECKSUM_H |
21 | |
22 | #include <linux/errno.h> |
23 | #include <asm/types.h> |
24 | #include <asm/byteorder.h> |
25 | #include <asm/uaccess.h> |
26 | #include <asm/checksum.h> |
27 | |
28 | #ifndef _HAVE_ARCH_COPY_AND_CSUM_FROM_USER |
29 | static inline |
30 | __wsum csum_and_copy_from_user (const void __user *src, void *dst, |
31 | int len, __wsum sum, int *err_ptr) |
32 | { |
33 | if (access_ok(VERIFY_READ, src, len)) |
34 | return csum_partial_copy_from_user(src, dst, len, sum, err_ptr); |
35 | |
36 | if (len) |
37 | *err_ptr = -EFAULT; |
38 | |
39 | return sum; |
40 | } |
41 | #endif |
42 | |
43 | #ifndef HAVE_CSUM_COPY_USER |
44 | static __inline__ __wsum csum_and_copy_to_user |
45 | (const void *src, void __user *dst, int len, __wsum sum, int *err_ptr) |
46 | { |
47 | sum = csum_partial(src, len, sum); |
48 | |
49 | if (access_ok(VERIFY_WRITE, dst, len)) { |
50 | if (copy_to_user(dst, src, len) == 0) |
51 | return sum; |
52 | } |
53 | if (len) |
54 | *err_ptr = -EFAULT; |
55 | |
56 | return (__force __wsum)-1; /* invalid checksum */ |
57 | } |
58 | #endif |
59 | |
60 | static inline __wsum csum_add(__wsum csum, __wsum addend) |
61 | { |
62 | u32 res = (__force u32)csum; |
63 | res += (__force u32)addend; |
64 | return (__force __wsum)(res + (res < (__force u32)addend)); |
65 | } |
66 | |
67 | static inline __wsum csum_sub(__wsum csum, __wsum addend) |
68 | { |
69 | return csum_add(csum, ~addend); |
70 | } |
71 | |
72 | static inline __wsum |
73 | csum_block_add(__wsum csum, __wsum csum2, int offset) |
74 | { |
75 | u32 sum = (__force u32)csum2; |
76 | if (offset&1) |
77 | sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF); |
78 | return csum_add(csum, (__force __wsum)sum); |
79 | } |
80 | |
81 | static inline __wsum |
82 | csum_block_sub(__wsum csum, __wsum csum2, int offset) |
83 | { |
84 | u32 sum = (__force u32)csum2; |
85 | if (offset&1) |
86 | sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF); |
87 | return csum_sub(csum, (__force __wsum)sum); |
88 | } |
89 | |
90 | static inline __wsum csum_unfold(__sum16 n) |
91 | { |
92 | return (__force __wsum)n; |
93 | } |
94 | |
95 | #define CSUM_MANGLED_0 ((__force __sum16)0xffff) |
96 | |
97 | static inline void csum_replace4(__sum16 *sum, __be32 from, __be32 to) |
98 | { |
99 | __be32 diff[] = { ~from, to }; |
100 | |
101 | *sum = csum_fold(csum_partial(diff, sizeof(diff), ~csum_unfold(*sum))); |
102 | } |
103 | |
104 | static inline void csum_replace2(__sum16 *sum, __be16 from, __be16 to) |
105 | { |
106 | csum_replace4(sum, (__force __be32)from, (__force __be32)to); |
107 | } |
108 | |
109 | struct sk_buff; |
110 | extern void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, |
111 | __be32 from, __be32 to, int pseudohdr); |
112 | extern void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb, |
113 | const __be32 *from, const __be32 *to, |
114 | int pseudohdr); |
115 | |
116 | static inline void inet_proto_csum_replace2(__sum16 *sum, struct sk_buff *skb, |
117 | __be16 from, __be16 to, |
118 | int pseudohdr) |
119 | { |
120 | inet_proto_csum_replace4(sum, skb, (__force __be32)from, |
121 | (__force __be32)to, pseudohdr); |
122 | } |
123 | |
124 | #endif |
125 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9