diff options
Diffstat (limited to 'libotr/libgcrypt-1.8.7/cipher/bufhelp.h')
| -rw-r--r-- | libotr/libgcrypt-1.8.7/cipher/bufhelp.h | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/libotr/libgcrypt-1.8.7/cipher/bufhelp.h b/libotr/libgcrypt-1.8.7/cipher/bufhelp.h new file mode 100644 index 0000000..83d3f53 --- /dev/null +++ b/libotr/libgcrypt-1.8.7/cipher/bufhelp.h @@ -0,0 +1,456 @@ +/* bufhelp.h - Some buffer manipulation helpers + * Copyright (C) 2012-2017 Jussi Kivilinna <jussi.kivilinna@iki.fi> + * + * This file is part of Libgcrypt. + * + * Libgcrypt is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * Libgcrypt is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this program; if not, see <http://www.gnu.org/licenses/>. + */ +#ifndef GCRYPT_BUFHELP_H +#define GCRYPT_BUFHELP_H + + +#include "g10lib.h" +#include "bithelp.h" + + +#undef BUFHELP_UNALIGNED_ACCESS +#if defined(HAVE_GCC_ATTRIBUTE_PACKED) && \ + defined(HAVE_GCC_ATTRIBUTE_ALIGNED) && \ + defined(HAVE_GCC_ATTRIBUTE_MAY_ALIAS) +/* Compiler is supports attributes needed for automatically issuing unaligned + memory access instructions. + */ +# define BUFHELP_UNALIGNED_ACCESS 1 +#endif + + +#undef BUFHELP_FAST_UNALIGNED_ACCESS +#if defined(BUFHELP_UNALIGNED_ACCESS) && \ + (defined(__i386__) || defined(__x86_64__) || \ + (defined(__arm__) && defined(__ARM_FEATURE_UNALIGNED)) || \ + defined(__aarch64__)) +/* These architectures are able of unaligned memory accesses and can + handle those fast. + */ +# define BUFHELP_FAST_UNALIGNED_ACCESS 1 +#endif + + +#ifdef BUFHELP_FAST_UNALIGNED_ACCESS +/* Define type with one-byte alignment on architectures with fast unaligned + memory accesses. + */ +typedef struct bufhelp_int_s +{ + uintptr_t a; +} __attribute__((packed, aligned(1), may_alias)) bufhelp_int_t; +#else +/* Define type with default alignment for other architectures (unaligned + accessed handled in per byte loops). + */ +#ifdef HAVE_GCC_ATTRIBUTE_MAY_ALIAS +typedef struct bufhelp_int_s +{ + uintptr_t a; +} __attribute__((may_alias)) bufhelp_int_t; +#else +typedef struct bufhelp_int_s +{ + uintptr_t a; +} bufhelp_int_t; +#endif +#endif + + +/* Optimized function for small buffer copying */ +static inline void +buf_cpy(void *_dst, const void *_src, size_t len) +{ +#if __GNUC__ >= 4 && (defined(__x86_64__) || defined(__i386__)) + /* For AMD64 and i386, memcpy is faster. */ + memcpy(_dst, _src, len); +#else + byte *dst = _dst; + const byte *src = _src; + bufhelp_int_t *ldst; + const bufhelp_int_t *lsrc; +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS + const unsigned int longmask = sizeof(bufhelp_int_t) - 1; + + /* Skip fast processing if buffers are unaligned. */ + if (UNLIKELY(((uintptr_t)dst | (uintptr_t)src) & longmask)) + goto do_bytes; +#endif + + ldst = (bufhelp_int_t *)(void *)dst; + lsrc = (const bufhelp_int_t *)(const void *)src; + + for (; len >= sizeof(bufhelp_int_t); len -= sizeof(bufhelp_int_t)) + (ldst++)->a = (lsrc++)->a; + + dst = (byte *)ldst; + src = (const byte *)lsrc; + +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS +do_bytes: +#endif + /* Handle tail. */ + for (; len; len--) + *dst++ = *src++; +#endif /*__GNUC__ >= 4 && (__x86_64__ || __i386__)*/ +} + + +/* Optimized function for buffer xoring */ +static inline void +buf_xor(void *_dst, const void *_src1, const void *_src2, size_t len) +{ + byte *dst = _dst; + const byte *src1 = _src1; + const byte *src2 = _src2; + bufhelp_int_t *ldst; + const bufhelp_int_t *lsrc1, *lsrc2; +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS + const unsigned int longmask = sizeof(bufhelp_int_t) - 1; + + /* Skip fast processing if buffers are unaligned. */ + if (UNLIKELY(((uintptr_t)dst | (uintptr_t)src1 | (uintptr_t)src2) & longmask)) + goto do_bytes; +#endif + + ldst = (bufhelp_int_t *)(void *)dst; + lsrc1 = (const bufhelp_int_t *)(const void *)src1; + lsrc2 = (const bufhelp_int_t *)(const void *)src2; + + for (; len >= sizeof(bufhelp_int_t); len -= sizeof(bufhelp_int_t)) + (ldst++)->a = (lsrc1++)->a ^ (lsrc2++)->a; + + dst = (byte *)ldst; + src1 = (const byte *)lsrc1; + src2 = (const byte *)lsrc2; + +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS +do_bytes: +#endif + /* Handle tail. */ + for (; len; len--) + *dst++ = *src1++ ^ *src2++; +} + + +/* Optimized function for in-place buffer xoring. */ +static inline void +buf_xor_1(void *_dst, const void *_src, size_t len) +{ + byte *dst = _dst; + const byte *src = _src; + bufhelp_int_t *ldst; + const bufhelp_int_t *lsrc; +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS + const unsigned int longmask = sizeof(bufhelp_int_t) - 1; + + /* Skip fast processing if buffers are unaligned. */ + if (UNLIKELY(((uintptr_t)dst | (uintptr_t)src) & longmask)) + goto do_bytes; +#endif + + ldst = (bufhelp_int_t *)(void *)dst; + lsrc = (const bufhelp_int_t *)(const void *)src; + + for (; len >= sizeof(bufhelp_int_t); len -= sizeof(bufhelp_int_t)) + (ldst++)->a ^= (lsrc++)->a; + + dst = (byte *)ldst; + src = (const byte *)lsrc; + +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS +do_bytes: +#endif + /* Handle tail. */ + for (; len; len--) + *dst++ ^= *src++; +} + + +/* Optimized function for buffer xoring with two destination buffers. Used + mainly by CFB mode encryption. */ +static inline void +buf_xor_2dst(void *_dst1, void *_dst2, const void *_src, size_t len) +{ + byte *dst1 = _dst1; + byte *dst2 = _dst2; + const byte *src = _src; + bufhelp_int_t *ldst1, *ldst2; + const bufhelp_int_t *lsrc; +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS + const unsigned int longmask = sizeof(bufhelp_int_t) - 1; + + /* Skip fast processing if buffers are unaligned. */ + if (UNLIKELY(((uintptr_t)src | (uintptr_t)dst1 | (uintptr_t)dst2) & longmask)) + goto do_bytes; +#endif + + ldst1 = (bufhelp_int_t *)(void *)dst1; + ldst2 = (bufhelp_int_t *)(void *)dst2; + lsrc = (const bufhelp_int_t *)(const void *)src; + + for (; len >= sizeof(bufhelp_int_t); len -= sizeof(bufhelp_int_t)) + (ldst1++)->a = ((ldst2++)->a ^= (lsrc++)->a); + + dst1 = (byte *)ldst1; + dst2 = (byte *)ldst2; + src = (const byte *)lsrc; + +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS +do_bytes: +#endif + /* Handle tail. */ + for (; len; len--) + *dst1++ = (*dst2++ ^= *src++); +} + + +/* Optimized function for combined buffer xoring and copying. Used by mainly + CBC mode decryption. */ +static inline void +buf_xor_n_copy_2(void *_dst_xor, const void *_src_xor, void *_srcdst_cpy, + const void *_src_cpy, size_t len) +{ + byte *dst_xor = _dst_xor; + byte *srcdst_cpy = _srcdst_cpy; + const byte *src_xor = _src_xor; + const byte *src_cpy = _src_cpy; + byte temp; + bufhelp_int_t *ldst_xor, *lsrcdst_cpy; + const bufhelp_int_t *lsrc_cpy, *lsrc_xor; + uintptr_t ltemp; +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS + const unsigned int longmask = sizeof(bufhelp_int_t) - 1; + + /* Skip fast processing if buffers are unaligned. */ + if (UNLIKELY(((uintptr_t)src_cpy | (uintptr_t)src_xor | (uintptr_t)dst_xor | + (uintptr_t)srcdst_cpy) & longmask)) + goto do_bytes; +#endif + + ldst_xor = (bufhelp_int_t *)(void *)dst_xor; + lsrc_xor = (const bufhelp_int_t *)(void *)src_xor; + lsrcdst_cpy = (bufhelp_int_t *)(void *)srcdst_cpy; + lsrc_cpy = (const bufhelp_int_t *)(const void *)src_cpy; + + for (; len >= sizeof(bufhelp_int_t); len -= sizeof(bufhelp_int_t)) + { + ltemp = (lsrc_cpy++)->a; + (ldst_xor++)->a = (lsrcdst_cpy)->a ^ (lsrc_xor++)->a; + (lsrcdst_cpy++)->a = ltemp; + } + + dst_xor = (byte *)ldst_xor; + src_xor = (const byte *)lsrc_xor; + srcdst_cpy = (byte *)lsrcdst_cpy; + src_cpy = (const byte *)lsrc_cpy; + +#ifndef BUFHELP_FAST_UNALIGNED_ACCESS +do_bytes: +#endif + /* Handle tail. */ + for (; len; len--) + { + temp = *src_cpy++; + *dst_xor++ = *srcdst_cpy ^ *src_xor++; + *srcdst_cpy++ = temp; + } +} + + +/* Optimized function for combined buffer xoring and copying. Used by mainly + CFB mode decryption. */ +static inline void +buf_xor_n_copy(void *_dst_xor, void *_srcdst_cpy, const void *_src, size_t len) +{ + buf_xor_n_copy_2(_dst_xor, _src, _srcdst_cpy, _src, len); +} + + +/* Constant-time compare of two buffers. Returns 1 if buffers are equal, + and 0 if buffers differ. */ +static inline int +buf_eq_const(const void *_a, const void *_b, size_t len) +{ + const byte *a = _a; + const byte *b = _b; + int ab, ba; + size_t i; + + /* Constant-time compare. */ + for (i = 0, ab = 0, ba = 0; i < len; i++) + { + /* If a[i] != b[i], either ab or ba will be negative. */ + ab |= a[i] - b[i]; + ba |= b[i] - a[i]; + } + + /* 'ab | ba' is negative when buffers are not equal. */ + return (ab | ba) >= 0; +} + + +#ifndef BUFHELP_UNALIGNED_ACCESS + +/* Functions for loading and storing unaligned u32 values of different + endianness. */ +static inline u32 buf_get_be32(const void *_buf) +{ + const byte *in = _buf; + return ((u32)in[0] << 24) | ((u32)in[1] << 16) | \ + ((u32)in[2] << 8) | (u32)in[3]; +} + +static inline u32 buf_get_le32(const void *_buf) +{ + const byte *in = _buf; + return ((u32)in[3] << 24) | ((u32)in[2] << 16) | \ + ((u32)in[1] << 8) | (u32)in[0]; +} + +static inline void buf_put_be32(void *_buf, u32 val) +{ + byte *out = _buf; + out[0] = val >> 24; + out[1] = val >> 16; + out[2] = val >> 8; + out[3] = val; +} + +static inline void buf_put_le32(void *_buf, u32 val) +{ + byte *out = _buf; + out[3] = val >> 24; + out[2] = val >> 16; + out[1] = val >> 8; + out[0] = val; +} + + +/* Functions for loading and storing unaligned u64 values of different + endianness. */ +static inline u64 buf_get_be64(const void *_buf) +{ + const byte *in = _buf; + return ((u64)in[0] << 56) | ((u64)in[1] << 48) | \ + ((u64)in[2] << 40) | ((u64)in[3] << 32) | \ + ((u64)in[4] << 24) | ((u64)in[5] << 16) | \ + ((u64)in[6] << 8) | (u64)in[7]; +} + +static inline u64 buf_get_le64(const void *_buf) +{ + const byte *in = _buf; + return ((u64)in[7] << 56) | ((u64)in[6] << 48) | \ + ((u64)in[5] << 40) | ((u64)in[4] << 32) | \ + ((u64)in[3] << 24) | ((u64)in[2] << 16) | \ + ((u64)in[1] << 8) | (u64)in[0]; +} + +static inline void buf_put_be64(void *_buf, u64 val) +{ + byte *out = _buf; + out[0] = val >> 56; + out[1] = val >> 48; + out[2] = val >> 40; + out[3] = val >> 32; + out[4] = val >> 24; + out[5] = val >> 16; + out[6] = val >> 8; + out[7] = val; +} + +static inline void buf_put_le64(void *_buf, u64 val) +{ + byte *out = _buf; + out[7] = val >> 56; + out[6] = val >> 48; + out[5] = val >> 40; + out[4] = val >> 32; + out[3] = val >> 24; + out[2] = val >> 16; + out[1] = val >> 8; + out[0] = val; +} + +#else /*BUFHELP_UNALIGNED_ACCESS*/ + +typedef struct bufhelp_u32_s +{ + u32 a; +} __attribute__((packed, aligned(1), may_alias)) bufhelp_u32_t; + +/* Functions for loading and storing unaligned u32 values of different + endianness. */ +static inline u32 buf_get_be32(const void *_buf) +{ + return be_bswap32(((const bufhelp_u32_t *)_buf)->a); +} + +static inline u32 buf_get_le32(const void *_buf) +{ + return le_bswap32(((const bufhelp_u32_t *)_buf)->a); +} + +static inline void buf_put_be32(void *_buf, u32 val) +{ + bufhelp_u32_t *out = _buf; + out->a = be_bswap32(val); +} + +static inline void buf_put_le32(void *_buf, u32 val) +{ + bufhelp_u32_t *out = _buf; + out->a = le_bswap32(val); +} + + +typedef struct bufhelp_u64_s +{ + u64 a; +} __attribute__((packed, aligned(1), may_alias)) bufhelp_u64_t; + +/* Functions for loading and storing unaligned u64 values of different + endianness. */ +static inline u64 buf_get_be64(const void *_buf) +{ + return be_bswap64(((const bufhelp_u64_t *)_buf)->a); +} + +static inline u64 buf_get_le64(const void *_buf) +{ + return le_bswap64(((const bufhelp_u64_t *)_buf)->a); +} + +static inline void buf_put_be64(void *_buf, u64 val) +{ + bufhelp_u64_t *out = _buf; + out->a = be_bswap64(val); +} + +static inline void buf_put_le64(void *_buf, u64 val) +{ + bufhelp_u64_t *out = _buf; + out->a = le_bswap64(val); +} + + +#endif /*BUFHELP_UNALIGNED_ACCESS*/ + +#endif /*GCRYPT_BUFHELP_H*/ |