diff options
Diffstat (limited to 'include/net/checksum.h')
| -rw-r--r-- | include/net/checksum.h | 171 |
1 files changed, 119 insertions, 52 deletions
diff --git a/include/net/checksum.h b/include/net/checksum.h index 600d1d705bb8..3cbab35de5ab 100644 --- a/include/net/checksum.h +++ b/include/net/checksum.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket @@ -9,11 +10,6 @@ * Arnt Gulbrandsen, <agulbra@nvg.unit.no> * Borrows very liberally from tcp.c and ip.c, see those * files for more names. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. */ #ifndef _CHECKSUM_H @@ -22,103 +18,174 @@ #include <linux/errno.h> #include <asm/types.h> #include <asm/byteorder.h> -#include <asm/uaccess.h> #include <asm/checksum.h> +#if !defined(_HAVE_ARCH_COPY_AND_CSUM_FROM_USER) || !defined(HAVE_CSUM_COPY_USER) +#include <linux/uaccess.h> +#endif #ifndef _HAVE_ARCH_COPY_AND_CSUM_FROM_USER -static inline +static __always_inline __wsum csum_and_copy_from_user (const void __user *src, void *dst, - int len, __wsum sum, int *err_ptr) + int len) { - if (access_ok(VERIFY_READ, src, len)) - return csum_partial_copy_from_user(src, dst, len, sum, err_ptr); - - if (len) - *err_ptr = -EFAULT; - - return sum; + if (copy_from_user(dst, src, len)) + return 0; + return csum_partial(dst, len, ~0U); } #endif #ifndef HAVE_CSUM_COPY_USER -static __inline__ __wsum csum_and_copy_to_user -(const void *src, void __user *dst, int len, __wsum sum, int *err_ptr) +static __always_inline __wsum csum_and_copy_to_user +(const void *src, void __user *dst, int len) { - sum = csum_partial(src, len, sum); + __wsum sum = csum_partial(src, len, ~0U); - if (access_ok(VERIFY_WRITE, dst, len)) { - if (copy_to_user(dst, src, len) == 0) - return sum; - } - if (len) - *err_ptr = -EFAULT; + if (copy_to_user(dst, src, len) == 0) + return sum; + return 0; +} +#endif - return (__force __wsum)-1; /* invalid checksum */ +#ifndef _HAVE_ARCH_CSUM_AND_COPY +static __always_inline __wsum +csum_partial_copy_nocheck(const void *src, void *dst, int len) +{ + memcpy(dst, src, len); + return csum_partial(dst, len, 0); } #endif -static inline __wsum csum_add(__wsum csum, __wsum addend) +#ifndef HAVE_ARCH_CSUM_ADD +static __always_inline __wsum csum_add(__wsum csum, __wsum addend) { u32 res = (__force u32)csum; res += (__force u32)addend; return (__force __wsum)(res + (res < (__force u32)addend)); } +#endif -static inline __wsum csum_sub(__wsum csum, __wsum addend) +static __always_inline __wsum csum_sub(__wsum csum, __wsum addend) { return csum_add(csum, ~addend); } -static inline __wsum +static __always_inline __sum16 csum16_add(__sum16 csum, __be16 addend) +{ + u16 res = (__force u16)csum; + + res += (__force u16)addend; + return (__force __sum16)(res + (res < (__force u16)addend)); +} + +static __always_inline __sum16 csum16_sub(__sum16 csum, __be16 addend) +{ + return csum16_add(csum, ~addend); +} + +#ifndef HAVE_ARCH_CSUM_SHIFT +static __always_inline __wsum csum_shift(__wsum sum, int offset) +{ + /* rotate sum to align it with a 16b boundary */ + if (offset & 1) + return (__force __wsum)ror32((__force u32)sum, 8); + return sum; +} +#endif + +static __always_inline __wsum csum_block_add(__wsum csum, __wsum csum2, int offset) { - u32 sum = (__force u32)csum2; - if (offset&1) - sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF); - return csum_add(csum, (__force __wsum)sum); + return csum_add(csum, csum_shift(csum2, offset)); } -static inline __wsum +static __always_inline __wsum csum_block_sub(__wsum csum, __wsum csum2, int offset) { - u32 sum = (__force u32)csum2; - if (offset&1) - sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF); - return csum_sub(csum, (__force __wsum)sum); + return csum_block_add(csum, ~csum2, offset); } -static inline __wsum csum_unfold(__sum16 n) +static __always_inline __wsum csum_unfold(__sum16 n) { return (__force __wsum)n; } #define CSUM_MANGLED_0 ((__force __sum16)0xffff) -static inline void csum_replace4(__sum16 *sum, __be32 from, __be32 to) +static __always_inline void csum_replace_by_diff(__sum16 *sum, __wsum diff) { - __be32 diff[] = { ~from, to }; + *sum = csum_fold(csum_add(diff, ~csum_unfold(*sum))); +} - *sum = csum_fold(csum_partial(diff, sizeof(diff), ~csum_unfold(*sum))); +static __always_inline void csum_replace4(__sum16 *sum, __be32 from, __be32 to) +{ + __wsum tmp = csum_sub(~csum_unfold(*sum), (__force __wsum)from); + + *sum = csum_fold(csum_add(tmp, (__force __wsum)to)); } -static inline void csum_replace2(__sum16 *sum, __be16 from, __be16 to) +/* Implements RFC 1624 (Incremental Internet Checksum) + * 3. Discussion states : + * HC' = ~(~HC + ~m + m') + * m : old value of a 16bit field + * m' : new value of a 16bit field + */ +static __always_inline void csum_replace2(__sum16 *sum, __be16 old, __be16 new) { - csum_replace4(sum, (__force __be32)from, (__force __be32)to); + *sum = ~csum16_add(csum16_sub(~(*sum), old), new); } -struct sk_buff; -extern void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, - __be32 from, __be32 to, int pseudohdr); -extern void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb, - const __be32 *from, const __be32 *to, - int pseudohdr); +static inline void csum_replace(__wsum *csum, __wsum old, __wsum new) +{ + *csum = csum_add(csum_sub(*csum, old), new); +} -static inline void inet_proto_csum_replace2(__sum16 *sum, struct sk_buff *skb, - __be16 from, __be16 to, - int pseudohdr) +static inline unsigned short csum_from32to16(unsigned int sum) +{ + sum += (sum >> 16) | (sum << 16); + return (unsigned short)(sum >> 16); +} + +struct sk_buff; +void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, + __be32 from, __be32 to, bool pseudohdr); +void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb, + const __be32 *from, const __be32 *to, + bool pseudohdr); +void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb, + __wsum diff, bool pseudohdr, bool ipv6); + +static __always_inline +void inet_proto_csum_replace2(__sum16 *sum, struct sk_buff *skb, + __be16 from, __be16 to, bool pseudohdr) { inet_proto_csum_replace4(sum, skb, (__force __be32)from, (__force __be32)to, pseudohdr); } +static __always_inline __wsum remcsum_adjust(void *ptr, __wsum csum, + int start, int offset) +{ + __sum16 *psum = (__sum16 *)(ptr + offset); + __wsum delta; + + /* Subtract out checksum up to start */ + csum = csum_sub(csum, csum_partial(ptr, start, 0)); + + /* Set derived checksum in packet */ + delta = csum_sub((__force __wsum)csum_fold(csum), + (__force __wsum)*psum); + *psum = csum_fold(csum); + + return delta; +} + +static __always_inline void remcsum_unadjust(__sum16 *psum, __wsum delta) +{ + *psum = csum_fold(csum_sub(delta, (__force __wsum)*psum)); +} + +static __always_inline __wsum wsum_negate(__wsum val) +{ + return (__force __wsum)-((__force u32)val); +} #endif |