Tidy up alignment-related code into separate header
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/library/alignment.h b/library/alignment.h
new file mode 100644
index 0000000..60e5dba
--- /dev/null
+++ b/library/alignment.h
@@ -0,0 +1,382 @@
+/**
+ * \file alignment.h
+ *
+ * \brief Utility code for dealing with unaligned memory accesses
+ */
+/*
+ * Copyright The Mbed TLS Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MBEDTLS_LIBRARY_ALIGNMENT_H
+#define MBEDTLS_LIBRARY_ALIGNMENT_H
+
+#include <stdint.h>
+
+/** MBEDTLS_ALLOW_UNALIGNED_ACCESS is defined for architectures where unaligned
+ * memory accesses are safe and performant.
+ *
+ * Unaligned accesses must be made via the UNALIGNED_UINT32_T type
+ * defined here.
+ *
+ * This list is incomplete.
+ */
+#if defined(__i386__) || defined(__amd64__) || defined( __x86_64__) \
+ || defined(__ARM_FEATURE_UNALIGNED) \
+ || defined(__aarch64__) \
+ || defined(__ARM_ARCH_8__) || defined(__ARM_ARCH_8A__) || defined(__ARM_ARCH_8M__) \
+ || defined(__ARM_ARCH_7A__)
+#if (defined(__GNUC__) && __GNUC__ >= 4) \
+ || (defined(__clang__) && __has_attribute(aligned)) \
+ || (defined(__ARMCC_VERSION) && __ARMCC_VERSION >= 5000000 )
+ /* GCC, Clang and armcc */
+#define MBEDTLS_ALLOW_UNALIGNED_ACCESS
+__attribute__((aligned(1))) typedef uint32_t mbedtls_unaligned_uint32_t;
+#define UNALIGNED_UINT32_T mbedtls_unaligned_uint32_t
+#elif defined(_MSC_VER)
+ /* MSVC */
+#define MBEDTLS_ALLOW_UNALIGNED_ACCESS
+#define UNALIGNED_UINT32_T __declspec(align(1)) uint32_t
+#elif (defined __ICCARM__)
+ /* IAR - this is disabled until we have the opportunity to test it */
+#undef MBEDTLS_ALLOW_UNALIGNED_ACCESS
+#define UNALIGNED_UINT32_T _Pragma("data_alignment = 1") uint32_t
+#endif
+#endif
+
+
+/** Byte Reading Macros
+ *
+ * Given a multi-byte integer \p x, MBEDTLS_BYTE_n retrieves the n-th
+ * byte from x, where byte 0 is the least significant byte.
+ */
+#define MBEDTLS_BYTE_0( x ) ( (uint8_t) ( ( x ) & 0xff ) )
+#define MBEDTLS_BYTE_1( x ) ( (uint8_t) ( ( ( x ) >> 8 ) & 0xff ) )
+#define MBEDTLS_BYTE_2( x ) ( (uint8_t) ( ( ( x ) >> 16 ) & 0xff ) )
+#define MBEDTLS_BYTE_3( x ) ( (uint8_t) ( ( ( x ) >> 24 ) & 0xff ) )
+#define MBEDTLS_BYTE_4( x ) ( (uint8_t) ( ( ( x ) >> 32 ) & 0xff ) )
+#define MBEDTLS_BYTE_5( x ) ( (uint8_t) ( ( ( x ) >> 40 ) & 0xff ) )
+#define MBEDTLS_BYTE_6( x ) ( (uint8_t) ( ( ( x ) >> 48 ) & 0xff ) )
+#define MBEDTLS_BYTE_7( x ) ( (uint8_t) ( ( ( x ) >> 56 ) & 0xff ) )
+
+/**
+ * Get the unsigned 32 bits integer corresponding to four bytes in
+ * big-endian order (MSB first).
+ *
+ * \param data Base address of the memory to get the four bytes from.
+ * \param offset Offset from \p data of the first and most significant
+ * byte of the four bytes to build the 32 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT32_BE
+#define MBEDTLS_GET_UINT32_BE( data , offset ) \
+ ( \
+ ( (uint32_t) ( data )[( offset ) ] << 24 ) \
+ | ( (uint32_t) ( data )[( offset ) + 1] << 16 ) \
+ | ( (uint32_t) ( data )[( offset ) + 2] << 8 ) \
+ | ( (uint32_t) ( data )[( offset ) + 3] ) \
+ )
+#endif
+
+/**
+ * Put in memory a 32 bits unsigned integer in big-endian order.
+ *
+ * \param n 32 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 32
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the most significant
+ * byte of the 32 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT32_BE
+#define MBEDTLS_PUT_UINT32_BE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_3( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_2( n ); \
+ ( data )[( offset ) + 2] = MBEDTLS_BYTE_1( n ); \
+ ( data )[( offset ) + 3] = MBEDTLS_BYTE_0( n ); \
+}
+#endif
+
+/**
+ * Get the unsigned 32 bits integer corresponding to four bytes in
+ * little-endian order (LSB first).
+ *
+ * \param data Base address of the memory to get the four bytes from.
+ * \param offset Offset from \p data of the first and least significant
+ * byte of the four bytes to build the 32 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT32_LE
+#define MBEDTLS_GET_UINT32_LE( data, offset ) \
+ ( \
+ ( (uint32_t) ( data )[( offset ) ] ) \
+ | ( (uint32_t) ( data )[( offset ) + 1] << 8 ) \
+ | ( (uint32_t) ( data )[( offset ) + 2] << 16 ) \
+ | ( (uint32_t) ( data )[( offset ) + 3] << 24 ) \
+ )
+#endif
+
+/**
+ * Put in memory a 32 bits unsigned integer in little-endian order.
+ *
+ * \param n 32 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 32
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the least significant
+ * byte of the 32 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT32_LE
+#define MBEDTLS_PUT_UINT32_LE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_0( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_1( n ); \
+ ( data )[( offset ) + 2] = MBEDTLS_BYTE_2( n ); \
+ ( data )[( offset ) + 3] = MBEDTLS_BYTE_3( n ); \
+}
+#endif
+
+/**
+ * Get the unsigned 16 bits integer corresponding to two bytes in
+ * little-endian order (LSB first).
+ *
+ * \param data Base address of the memory to get the two bytes from.
+ * \param offset Offset from \p data of the first and least significant
+ * byte of the two bytes to build the 16 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT16_LE
+#define MBEDTLS_GET_UINT16_LE( data, offset ) \
+ ( \
+ ( (uint16_t) ( data )[( offset ) ] ) \
+ | ( (uint16_t) ( data )[( offset ) + 1] << 8 ) \
+ )
+#endif
+
+/**
+ * Put in memory a 16 bits unsigned integer in little-endian order.
+ *
+ * \param n 16 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 16
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the least significant
+ * byte of the 16 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT16_LE
+#define MBEDTLS_PUT_UINT16_LE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_0( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_1( n ); \
+}
+#endif
+
+/**
+ * Get the unsigned 16 bits integer corresponding to two bytes in
+ * big-endian order (MSB first).
+ *
+ * \param data Base address of the memory to get the two bytes from.
+ * \param offset Offset from \p data of the first and most significant
+ * byte of the two bytes to build the 16 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT16_BE
+#define MBEDTLS_GET_UINT16_BE( data, offset ) \
+ ( \
+ ( (uint16_t) ( data )[( offset ) ] << 8 ) \
+ | ( (uint16_t) ( data )[( offset ) + 1] ) \
+ )
+#endif
+
+/**
+ * Put in memory a 16 bits unsigned integer in big-endian order.
+ *
+ * \param n 16 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 16
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the most significant
+ * byte of the 16 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT16_BE
+#define MBEDTLS_PUT_UINT16_BE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_1( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_0( n ); \
+}
+#endif
+
+/**
+ * Get the unsigned 24 bits integer corresponding to three bytes in
+ * big-endian order (MSB first).
+ *
+ * \param data Base address of the memory to get the three bytes from.
+ * \param offset Offset from \p data of the first and most significant
+ * byte of the three bytes to build the 24 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT24_BE
+#define MBEDTLS_GET_UINT24_BE( data , offset ) \
+ ( \
+ ( (uint32_t) ( data )[( offset ) ] << 16 ) \
+ | ( (uint32_t) ( data )[( offset ) + 1] << 8 ) \
+ | ( (uint32_t) ( data )[( offset ) + 2] ) \
+ )
+#endif
+
+/**
+ * Put in memory a 24 bits unsigned integer in big-endian order.
+ *
+ * \param n 24 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 24
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the most significant
+ * byte of the 24 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT24_BE
+#define MBEDTLS_PUT_UINT24_BE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_2( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_1( n ); \
+ ( data )[( offset ) + 2] = MBEDTLS_BYTE_0( n ); \
+}
+#endif
+
+/**
+ * Get the unsigned 24 bits integer corresponding to three bytes in
+ * little-endian order (LSB first).
+ *
+ * \param data Base address of the memory to get the three bytes from.
+ * \param offset Offset from \p data of the first and least significant
+ * byte of the three bytes to build the 24 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT24_LE
+#define MBEDTLS_GET_UINT24_LE( data, offset ) \
+ ( \
+ ( (uint32_t) ( data )[( offset ) ] ) \
+ | ( (uint32_t) ( data )[( offset ) + 1] << 8 ) \
+ | ( (uint32_t) ( data )[( offset ) + 2] << 16 ) \
+ )
+#endif
+
+/**
+ * Put in memory a 24 bits unsigned integer in little-endian order.
+ *
+ * \param n 24 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 24
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the least significant
+ * byte of the 24 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT24_LE
+#define MBEDTLS_PUT_UINT24_LE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_0( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_1( n ); \
+ ( data )[( offset ) + 2] = MBEDTLS_BYTE_2( n ); \
+}
+#endif
+
+/**
+ * Get the unsigned 64 bits integer corresponding to eight bytes in
+ * big-endian order (MSB first).
+ *
+ * \param data Base address of the memory to get the eight bytes from.
+ * \param offset Offset from \p data of the first and most significant
+ * byte of the eight bytes to build the 64 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT64_BE
+#define MBEDTLS_GET_UINT64_BE( data, offset ) \
+ ( \
+ ( (uint64_t) ( data )[( offset ) ] << 56 ) \
+ | ( (uint64_t) ( data )[( offset ) + 1] << 48 ) \
+ | ( (uint64_t) ( data )[( offset ) + 2] << 40 ) \
+ | ( (uint64_t) ( data )[( offset ) + 3] << 32 ) \
+ | ( (uint64_t) ( data )[( offset ) + 4] << 24 ) \
+ | ( (uint64_t) ( data )[( offset ) + 5] << 16 ) \
+ | ( (uint64_t) ( data )[( offset ) + 6] << 8 ) \
+ | ( (uint64_t) ( data )[( offset ) + 7] ) \
+ )
+#endif
+
+/**
+ * Put in memory a 64 bits unsigned integer in big-endian order.
+ *
+ * \param n 64 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 64
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the most significant
+ * byte of the 64 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT64_BE
+#define MBEDTLS_PUT_UINT64_BE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_7( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_6( n ); \
+ ( data )[( offset ) + 2] = MBEDTLS_BYTE_5( n ); \
+ ( data )[( offset ) + 3] = MBEDTLS_BYTE_4( n ); \
+ ( data )[( offset ) + 4] = MBEDTLS_BYTE_3( n ); \
+ ( data )[( offset ) + 5] = MBEDTLS_BYTE_2( n ); \
+ ( data )[( offset ) + 6] = MBEDTLS_BYTE_1( n ); \
+ ( data )[( offset ) + 7] = MBEDTLS_BYTE_0( n ); \
+}
+#endif
+
+/**
+ * Get the unsigned 64 bits integer corresponding to eight bytes in
+ * little-endian order (LSB first).
+ *
+ * \param data Base address of the memory to get the eight bytes from.
+ * \param offset Offset from \p data of the first and least significant
+ * byte of the eight bytes to build the 64 bits unsigned
+ * integer from.
+ */
+#ifndef MBEDTLS_GET_UINT64_LE
+#define MBEDTLS_GET_UINT64_LE( data, offset ) \
+ ( \
+ ( (uint64_t) ( data )[( offset ) + 7] << 56 ) \
+ | ( (uint64_t) ( data )[( offset ) + 6] << 48 ) \
+ | ( (uint64_t) ( data )[( offset ) + 5] << 40 ) \
+ | ( (uint64_t) ( data )[( offset ) + 4] << 32 ) \
+ | ( (uint64_t) ( data )[( offset ) + 3] << 24 ) \
+ | ( (uint64_t) ( data )[( offset ) + 2] << 16 ) \
+ | ( (uint64_t) ( data )[( offset ) + 1] << 8 ) \
+ | ( (uint64_t) ( data )[( offset ) ] ) \
+ )
+#endif
+
+/**
+ * Put in memory a 64 bits unsigned integer in little-endian order.
+ *
+ * \param n 64 bits unsigned integer to put in memory.
+ * \param data Base address of the memory where to put the 64
+ * bits unsigned integer in.
+ * \param offset Offset from \p data where to put the least significant
+ * byte of the 64 bits unsigned integer \p n.
+ */
+#ifndef MBEDTLS_PUT_UINT64_LE
+#define MBEDTLS_PUT_UINT64_LE( n, data, offset ) \
+{ \
+ ( data )[( offset ) ] = MBEDTLS_BYTE_0( n ); \
+ ( data )[( offset ) + 1] = MBEDTLS_BYTE_1( n ); \
+ ( data )[( offset ) + 2] = MBEDTLS_BYTE_2( n ); \
+ ( data )[( offset ) + 3] = MBEDTLS_BYTE_3( n ); \
+ ( data )[( offset ) + 4] = MBEDTLS_BYTE_4( n ); \
+ ( data )[( offset ) + 5] = MBEDTLS_BYTE_5( n ); \
+ ( data )[( offset ) + 6] = MBEDTLS_BYTE_6( n ); \
+ ( data )[( offset ) + 7] = MBEDTLS_BYTE_7( n ); \
+}
+#endif
+
+#endif /* MBEDTLS_LIBRARY_ALIGNMENT_H */