1384740dcSRalf Baechle /*
2384740dcSRalf Baechle * This file is subject to the terms and conditions of the GNU General Public
3384740dcSRalf Baechle * License. See the file "COPYING" in the main directory of this archive
4384740dcSRalf Baechle * for more details.
5384740dcSRalf Baechle *
6384740dcSRalf Baechle * Copyright (C) 1995, 96, 97, 98, 99, 2001 by Ralf Baechle
7384740dcSRalf Baechle * Copyright (C) 1999 Silicon Graphics, Inc.
8384740dcSRalf Baechle * Copyright (C) 2001 Thiemo Seufer.
9384740dcSRalf Baechle * Copyright (C) 2002 Maciej W. Rozycki
10ac85227fSMarkos Chandras * Copyright (C) 2014 Imagination Technologies Ltd.
11384740dcSRalf Baechle */
12384740dcSRalf Baechle #ifndef _ASM_CHECKSUM_H
13384740dcSRalf Baechle #define _ASM_CHECKSUM_H
14384740dcSRalf Baechle
154e0748f5SMarkos Chandras #ifdef CONFIG_GENERIC_CSUM
164e0748f5SMarkos Chandras #include <asm-generic/checksum.h>
174e0748f5SMarkos Chandras #else
184e0748f5SMarkos Chandras
19384740dcSRalf Baechle #include <linux/in6.h>
20384740dcSRalf Baechle
217c0f6ba6SLinus Torvalds #include <linux/uaccess.h>
22384740dcSRalf Baechle
23384740dcSRalf Baechle /*
24384740dcSRalf Baechle * computes the checksum of a memory block at buff, length len,
25384740dcSRalf Baechle * and adds in "sum" (32-bit)
26384740dcSRalf Baechle *
27384740dcSRalf Baechle * returns a 32-bit number suitable for feeding into itself
28384740dcSRalf Baechle * or csum_tcpudp_magic
29384740dcSRalf Baechle *
30384740dcSRalf Baechle * this function must be called with even lengths, except
31384740dcSRalf Baechle * for the last fragment, which may be odd
32384740dcSRalf Baechle *
33384740dcSRalf Baechle * it's best to have buff aligned on a 32-bit boundary
34384740dcSRalf Baechle */
35384740dcSRalf Baechle __wsum csum_partial(const void *buff, int len, __wsum sum);
36384740dcSRalf Baechle
371cd95ab8SAl Viro __wsum __csum_partial_copy_from_user(const void __user *src, void *dst, int len);
381cd95ab8SAl Viro __wsum __csum_partial_copy_to_user(const void *src, void __user *dst, int len);
39384740dcSRalf Baechle
40c2d85bc1SLeonid Yegoshin #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
41c2d85bc1SLeonid Yegoshin static inline
csum_and_copy_from_user(const void __user * src,void * dst,int len)42c693cc46SAl Viro __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)
43c2d85bc1SLeonid Yegoshin {
44c44ac3c8SAl Viro might_fault();
45c693cc46SAl Viro if (!access_ok(src, len))
46c693cc46SAl Viro return 0;
471cd95ab8SAl Viro return __csum_partial_copy_from_user(src, dst, len);
48c2d85bc1SLeonid Yegoshin }
49c2d85bc1SLeonid Yegoshin
50384740dcSRalf Baechle /*
51384740dcSRalf Baechle * Copy and checksum to user
52384740dcSRalf Baechle */
53384740dcSRalf Baechle #define HAVE_CSUM_COPY_USER
54384740dcSRalf Baechle static inline
csum_and_copy_to_user(const void * src,void __user * dst,int len)55c693cc46SAl Viro __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
56384740dcSRalf Baechle {
57c693cc46SAl Viro might_fault();
58c693cc46SAl Viro if (!access_ok(dst, len))
59c693cc46SAl Viro return 0;
601cd95ab8SAl Viro return __csum_partial_copy_to_user(src, dst, len);
61384740dcSRalf Baechle }
62384740dcSRalf Baechle
63384740dcSRalf Baechle /*
64384740dcSRalf Baechle * the same as csum_partial, but copies from user space (but on MIPS
65384740dcSRalf Baechle * we have just one address space, so this is identical to the above)
66384740dcSRalf Baechle */
676e41c585SAl Viro #define _HAVE_ARCH_CSUM_AND_COPY
681cd95ab8SAl Viro __wsum __csum_partial_copy_nocheck(const void *src, void *dst, int len);
csum_partial_copy_nocheck(const void * src,void * dst,int len)69cc44c17bSAl Viro static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
70cc44c17bSAl Viro {
711cd95ab8SAl Viro return __csum_partial_copy_nocheck(src, dst, len);
72cc44c17bSAl Viro }
73384740dcSRalf Baechle
74384740dcSRalf Baechle /*
75384740dcSRalf Baechle * Fold a partial checksum without adding pseudo headers
76384740dcSRalf Baechle */
csum_fold(__wsum csum)77d0f0f63aSRalf Baechle static inline __sum16 csum_fold(__wsum csum)
78384740dcSRalf Baechle {
79cc480444SLuis de Bethencourt u32 sum = (__force u32)csum;
80384740dcSRalf Baechle
81d0f0f63aSRalf Baechle sum += (sum << 16);
82ff711d67SAlexander Lobakin csum = (__force __wsum)(sum < (__force u32)csum);
83d0f0f63aSRalf Baechle sum >>= 16;
84ff711d67SAlexander Lobakin sum += (__force u32)csum;
85d0f0f63aSRalf Baechle
86d0f0f63aSRalf Baechle return (__force __sum16)~sum;
87384740dcSRalf Baechle }
88b4b5015aSRalf Baechle #define csum_fold csum_fold
89384740dcSRalf Baechle
90384740dcSRalf Baechle /*
91384740dcSRalf Baechle * This is a version of ip_compute_csum() optimized for IP headers,
92384740dcSRalf Baechle * which always checksum on 4 octet boundaries.
93384740dcSRalf Baechle *
94384740dcSRalf Baechle * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by
95384740dcSRalf Baechle * Arnt Gulbrandsen.
96384740dcSRalf Baechle */
ip_fast_csum(const void * iph,unsigned int ihl)97384740dcSRalf Baechle static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
98384740dcSRalf Baechle {
99384740dcSRalf Baechle const unsigned int *word = iph;
100384740dcSRalf Baechle const unsigned int *stop = word + ihl;
101384740dcSRalf Baechle unsigned int csum;
102384740dcSRalf Baechle int carry;
103384740dcSRalf Baechle
104384740dcSRalf Baechle csum = word[0];
105384740dcSRalf Baechle csum += word[1];
106384740dcSRalf Baechle carry = (csum < word[1]);
107384740dcSRalf Baechle csum += carry;
108384740dcSRalf Baechle
109384740dcSRalf Baechle csum += word[2];
110384740dcSRalf Baechle carry = (csum < word[2]);
111384740dcSRalf Baechle csum += carry;
112384740dcSRalf Baechle
113384740dcSRalf Baechle csum += word[3];
114384740dcSRalf Baechle carry = (csum < word[3]);
115384740dcSRalf Baechle csum += carry;
116384740dcSRalf Baechle
117384740dcSRalf Baechle word += 4;
118384740dcSRalf Baechle do {
119384740dcSRalf Baechle csum += *word;
120384740dcSRalf Baechle carry = (csum < *word);
121384740dcSRalf Baechle csum += carry;
122384740dcSRalf Baechle word++;
123384740dcSRalf Baechle } while (word != stop);
124384740dcSRalf Baechle
125384740dcSRalf Baechle return csum_fold(csum);
126384740dcSRalf Baechle }
127b4b5015aSRalf Baechle #define ip_fast_csum ip_fast_csum
128384740dcSRalf Baechle
csum_tcpudp_nofold(__be32 saddr,__be32 daddr,__u32 len,__u8 proto,__wsum isum)12901cfbad7SAlexander Duyck static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
13001cfbad7SAlexander Duyck __u32 len, __u8 proto,
13184aa8510SMaciej W. Rozycki __wsum isum)
132384740dcSRalf Baechle {
13384aa8510SMaciej W. Rozycki const unsigned int sh32 = IS_ENABLED(CONFIG_64BIT) ? 32 : 0;
13484aa8510SMaciej W. Rozycki unsigned long sum = (__force unsigned long)daddr;
13584aa8510SMaciej W. Rozycki unsigned long tmp;
13684aa8510SMaciej W. Rozycki __u32 osum;
137198688edSTiezhu Yang
13884aa8510SMaciej W. Rozycki tmp = (__force unsigned long)saddr;
13984aa8510SMaciej W. Rozycki sum += tmp;
140384740dcSRalf Baechle
14184aa8510SMaciej W. Rozycki if (IS_ENABLED(CONFIG_32BIT))
14284aa8510SMaciej W. Rozycki sum += sum < tmp;
143384740dcSRalf Baechle
14484aa8510SMaciej W. Rozycki /*
14584aa8510SMaciej W. Rozycki * We know PROTO + LEN has the sign bit clear, so cast to a signed
14684aa8510SMaciej W. Rozycki * type to avoid an extraneous zero-extension where TMP is 64-bit.
14784aa8510SMaciej W. Rozycki */
14884aa8510SMaciej W. Rozycki tmp = (__s32)(proto + len);
14984aa8510SMaciej W. Rozycki tmp <<= IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? 8 : 0;
15084aa8510SMaciej W. Rozycki sum += tmp;
15184aa8510SMaciej W. Rozycki if (IS_ENABLED(CONFIG_32BIT))
15284aa8510SMaciej W. Rozycki sum += sum < tmp;
153384740dcSRalf Baechle
15484aa8510SMaciej W. Rozycki tmp = (__force unsigned long)isum;
15584aa8510SMaciej W. Rozycki sum += tmp;
15684aa8510SMaciej W. Rozycki
15784aa8510SMaciej W. Rozycki if (IS_ENABLED(CONFIG_32BIT)) {
15884aa8510SMaciej W. Rozycki sum += sum < tmp;
15984aa8510SMaciej W. Rozycki osum = sum;
16084aa8510SMaciej W. Rozycki } else if (IS_ENABLED(CONFIG_64BIT)) {
16184aa8510SMaciej W. Rozycki tmp = sum << sh32;
16284aa8510SMaciej W. Rozycki sum += tmp;
16384aa8510SMaciej W. Rozycki osum = sum < tmp;
16484aa8510SMaciej W. Rozycki osum += sum >> sh32;
16584aa8510SMaciej W. Rozycki } else {
16684aa8510SMaciej W. Rozycki BUILD_BUG();
16784aa8510SMaciej W. Rozycki }
16884aa8510SMaciej W. Rozycki
16984aa8510SMaciej W. Rozycki return (__force __wsum)osum;
170384740dcSRalf Baechle }
171b4b5015aSRalf Baechle #define csum_tcpudp_nofold csum_tcpudp_nofold
172384740dcSRalf Baechle
173384740dcSRalf Baechle /*
174384740dcSRalf Baechle * this routine is used for miscellaneous IP-like checksums, mainly
175384740dcSRalf Baechle * in icmp.c
176384740dcSRalf Baechle */
ip_compute_csum(const void * buff,int len)177384740dcSRalf Baechle static inline __sum16 ip_compute_csum(const void *buff, int len)
178384740dcSRalf Baechle {
179384740dcSRalf Baechle return csum_fold(csum_partial(buff, len, 0));
180384740dcSRalf Baechle }
181384740dcSRalf Baechle
182384740dcSRalf Baechle #define _HAVE_ARCH_IPV6_CSUM
csum_ipv6_magic(const struct in6_addr * saddr,const struct in6_addr * daddr,__u32 len,__u8 proto,__wsum sum)183384740dcSRalf Baechle static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
184384740dcSRalf Baechle const struct in6_addr *daddr,
1851e940829SAlexander Duyck __u32 len, __u8 proto,
186384740dcSRalf Baechle __wsum sum)
187384740dcSRalf Baechle {
18820c82d93SDaniel Sanders __wsum tmp;
18920c82d93SDaniel Sanders
190384740dcSRalf Baechle __asm__(
191384740dcSRalf Baechle " .set push # csum_ipv6_magic\n"
192384740dcSRalf Baechle " .set noreorder \n"
193384740dcSRalf Baechle " .set noat \n"
194384740dcSRalf Baechle " addu %0, %5 # proto (long in network byte order)\n"
195384740dcSRalf Baechle " sltu $1, %0, %5 \n"
196384740dcSRalf Baechle " addu %0, $1 \n"
197384740dcSRalf Baechle
198384740dcSRalf Baechle " addu %0, %6 # csum\n"
199384740dcSRalf Baechle " sltu $1, %0, %6 \n"
200384740dcSRalf Baechle " lw %1, 0(%2) # four words source address\n"
201384740dcSRalf Baechle " addu %0, $1 \n"
202384740dcSRalf Baechle " addu %0, %1 \n"
203384740dcSRalf Baechle " sltu $1, %0, %1 \n"
204384740dcSRalf Baechle
205384740dcSRalf Baechle " lw %1, 4(%2) \n"
206384740dcSRalf Baechle " addu %0, $1 \n"
207384740dcSRalf Baechle " addu %0, %1 \n"
208384740dcSRalf Baechle " sltu $1, %0, %1 \n"
209384740dcSRalf Baechle
210384740dcSRalf Baechle " lw %1, 8(%2) \n"
211384740dcSRalf Baechle " addu %0, $1 \n"
212384740dcSRalf Baechle " addu %0, %1 \n"
213384740dcSRalf Baechle " sltu $1, %0, %1 \n"
214384740dcSRalf Baechle
215384740dcSRalf Baechle " lw %1, 12(%2) \n"
216384740dcSRalf Baechle " addu %0, $1 \n"
217384740dcSRalf Baechle " addu %0, %1 \n"
218384740dcSRalf Baechle " sltu $1, %0, %1 \n"
219384740dcSRalf Baechle
220384740dcSRalf Baechle " lw %1, 0(%3) \n"
221384740dcSRalf Baechle " addu %0, $1 \n"
222384740dcSRalf Baechle " addu %0, %1 \n"
223384740dcSRalf Baechle " sltu $1, %0, %1 \n"
224384740dcSRalf Baechle
225384740dcSRalf Baechle " lw %1, 4(%3) \n"
226384740dcSRalf Baechle " addu %0, $1 \n"
227384740dcSRalf Baechle " addu %0, %1 \n"
228384740dcSRalf Baechle " sltu $1, %0, %1 \n"
229384740dcSRalf Baechle
230384740dcSRalf Baechle " lw %1, 8(%3) \n"
231384740dcSRalf Baechle " addu %0, $1 \n"
232384740dcSRalf Baechle " addu %0, %1 \n"
233384740dcSRalf Baechle " sltu $1, %0, %1 \n"
234384740dcSRalf Baechle
235384740dcSRalf Baechle " lw %1, 12(%3) \n"
236384740dcSRalf Baechle " addu %0, $1 \n"
237384740dcSRalf Baechle " addu %0, %1 \n"
238384740dcSRalf Baechle " sltu $1, %0, %1 \n"
239384740dcSRalf Baechle
240384740dcSRalf Baechle " addu %0, $1 # Add final carry\n"
241384740dcSRalf Baechle " .set pop"
24220c82d93SDaniel Sanders : "=&r" (sum), "=&r" (tmp)
243384740dcSRalf Baechle : "r" (saddr), "r" (daddr),
244*2252913fSGuenter Roeck "0" (htonl(len)), "r" (htonl(proto)), "r" (sum)
245*2252913fSGuenter Roeck : "memory");
246384740dcSRalf Baechle
247384740dcSRalf Baechle return csum_fold(sum);
248384740dcSRalf Baechle }
249384740dcSRalf Baechle
250b4b5015aSRalf Baechle #include <asm-generic/checksum.h>
2514e0748f5SMarkos Chandras #endif /* CONFIG_GENERIC_CSUM */
252b4b5015aSRalf Baechle
253384740dcSRalf Baechle #endif /* _ASM_CHECKSUM_H */
254