From 626a8d8d3df8880991684d6d1a06b82f6685b51a Mon Sep 17 00:00:00 2001 From: vnugent Date: Sun, 28 Jan 2024 19:23:18 -0500 Subject: initial commit --- include/mbedtls/aes.h | 627 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 627 insertions(+) create mode 100644 include/mbedtls/aes.h (limited to 'include/mbedtls/aes.h') diff --git a/include/mbedtls/aes.h b/include/mbedtls/aes.h new file mode 100644 index 0000000..77ecffd --- /dev/null +++ b/include/mbedtls/aes.h @@ -0,0 +1,627 @@ +/** + * \file aes.h + * + * \brief This file contains AES definitions and functions. + * + * The Advanced Encryption Standard (AES) specifies a FIPS-approved + * cryptographic algorithm that can be used to protect electronic + * data. + * + * The AES algorithm is a symmetric block cipher that can + * encrypt and decrypt information. For more information, see + * FIPS Publication 197: Advanced Encryption Standard and + * ISO/IEC 18033-2:2006: Information technology -- Security + * techniques -- Encryption algorithms -- Part 2: Asymmetric + * ciphers. + * + * The AES-XTS block mode is standardized by NIST SP 800-38E + * + * and described in detail by IEEE P1619 + * . + */ + +/* + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ + +#ifndef MBEDTLS_AES_H +#define MBEDTLS_AES_H +#include "mbedtls/private_access.h" + +#include "mbedtls/build_info.h" +#include "mbedtls/platform_util.h" + +#include +#include + +/* padlock.c and aesni.c rely on these values! */ +#define MBEDTLS_AES_ENCRYPT 1 /**< AES encryption. */ +#define MBEDTLS_AES_DECRYPT 0 /**< AES decryption. */ + +/* Error codes in range 0x0020-0x0022 */ +/** Invalid key length. */ +#define MBEDTLS_ERR_AES_INVALID_KEY_LENGTH -0x0020 +/** Invalid data input length. */ +#define MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH -0x0022 + +/* Error codes in range 0x0021-0x0025 */ +/** Invalid input data. */ +#define MBEDTLS_ERR_AES_BAD_INPUT_DATA -0x0021 + +#ifdef __cplusplus +extern "C" { +#endif + +#if !defined(MBEDTLS_AES_ALT) +// Regular implementation +// + +/** + * \brief The AES context-type definition. + */ +typedef struct mbedtls_aes_context { + int MBEDTLS_PRIVATE(nr); /*!< The number of rounds. */ + size_t MBEDTLS_PRIVATE(rk_offset); /*!< The offset in array elements to AES + round keys in the buffer. */ +#if defined(MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH) && !defined(MBEDTLS_PADLOCK_C) + uint32_t MBEDTLS_PRIVATE(buf)[44]; /*!< Aligned data buffer to hold + 10 round keys for 128-bit case. */ +#else + uint32_t MBEDTLS_PRIVATE(buf)[68]; /*!< Unaligned data buffer. This buffer can + hold 32 extra Bytes, which can be used for + one of the following purposes: +
  • Alignment if VIA padlock is + used.
    • +
  • Simplifying key expansion in the 256-bit + case by generating an extra round key. +
*/ +#endif /* MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH && !MBEDTLS_PADLOCK_C */ +} +mbedtls_aes_context; + +#if defined(MBEDTLS_CIPHER_MODE_XTS) +/** + * \brief The AES XTS context-type definition. + */ +typedef struct mbedtls_aes_xts_context { + mbedtls_aes_context MBEDTLS_PRIVATE(crypt); /*!< The AES context to use for AES block + encryption or decryption. */ + mbedtls_aes_context MBEDTLS_PRIVATE(tweak); /*!< The AES context used for tweak + computation. */ +} mbedtls_aes_xts_context; +#endif /* MBEDTLS_CIPHER_MODE_XTS */ + +#else /* MBEDTLS_AES_ALT */ +#include "aes_alt.h" +#endif /* MBEDTLS_AES_ALT */ + +/** + * \brief This function initializes the specified AES context. + * + * It must be the first API called before using + * the context. + * + * \param ctx The AES context to initialize. This must not be \c NULL. + */ +void mbedtls_aes_init(mbedtls_aes_context *ctx); + +/** + * \brief This function releases and clears the specified AES context. + * + * \param ctx The AES context to clear. + * If this is \c NULL, this function does nothing. + * Otherwise, the context must have been at least initialized. + */ +void mbedtls_aes_free(mbedtls_aes_context *ctx); + +#if defined(MBEDTLS_CIPHER_MODE_XTS) +/** + * \brief This function initializes the specified AES XTS context. + * + * It must be the first API called before using + * the context. + * + * \param ctx The AES XTS context to initialize. This must not be \c NULL. + */ +void mbedtls_aes_xts_init(mbedtls_aes_xts_context *ctx); + +/** + * \brief This function releases and clears the specified AES XTS context. + * + * \param ctx The AES XTS context to clear. + * If this is \c NULL, this function does nothing. + * Otherwise, the context must have been at least initialized. + */ +void mbedtls_aes_xts_free(mbedtls_aes_xts_context *ctx); +#endif /* MBEDTLS_CIPHER_MODE_XTS */ + +/** + * \brief This function sets the encryption key. + * + * \param ctx The AES context to which the key should be bound. + * It must be initialized. + * \param key The encryption key. + * This must be a readable buffer of size \p keybits bits. + * \param keybits The size of data passed in bits. Valid options are: + *
  • 128 bits
    • + *
  • 192 bits
    • + *
  • 256 bits
+ * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_setkey_enc(mbedtls_aes_context *ctx, const unsigned char *key, + unsigned int keybits); + +/** + * \brief This function sets the decryption key. + * + * \param ctx The AES context to which the key should be bound. + * It must be initialized. + * \param key The decryption key. + * This must be a readable buffer of size \p keybits bits. + * \param keybits The size of data passed. Valid options are: + *
  • 128 bits
    • + *
  • 192 bits
    • + *
  • 256 bits
+ * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_setkey_dec(mbedtls_aes_context *ctx, const unsigned char *key, + unsigned int keybits); + +#if defined(MBEDTLS_CIPHER_MODE_XTS) +/** + * \brief This function prepares an XTS context for encryption and + * sets the encryption key. + * + * \param ctx The AES XTS context to which the key should be bound. + * It must be initialized. + * \param key The encryption key. This is comprised of the XTS key1 + * concatenated with the XTS key2. + * This must be a readable buffer of size \p keybits bits. + * \param keybits The size of \p key passed in bits. Valid options are: + *
  • 256 bits (each of key1 and key2 is a 128-bit key)
    • + *
  • 512 bits (each of key1 and key2 is a 256-bit key)
+ * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_xts_setkey_enc(mbedtls_aes_xts_context *ctx, + const unsigned char *key, + unsigned int keybits); + +/** + * \brief This function prepares an XTS context for decryption and + * sets the decryption key. + * + * \param ctx The AES XTS context to which the key should be bound. + * It must be initialized. + * \param key The decryption key. This is comprised of the XTS key1 + * concatenated with the XTS key2. + * This must be a readable buffer of size \p keybits bits. + * \param keybits The size of \p key passed in bits. Valid options are: + *
  • 256 bits (each of key1 and key2 is a 128-bit key)
    • + *
  • 512 bits (each of key1 and key2 is a 256-bit key)
+ * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_xts_setkey_dec(mbedtls_aes_xts_context *ctx, + const unsigned char *key, + unsigned int keybits); +#endif /* MBEDTLS_CIPHER_MODE_XTS */ + +/** + * \brief This function performs an AES single-block encryption or + * decryption operation. + * + * It performs the operation defined in the \p mode parameter + * (encrypt or decrypt), on the input data buffer defined in + * the \p input parameter. + * + * mbedtls_aes_init(), and either mbedtls_aes_setkey_enc() or + * mbedtls_aes_setkey_dec() must be called before the first + * call to this API with the same context. + * + * \param ctx The AES context to use for encryption or decryption. + * It must be initialized and bound to a key. + * \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or + * #MBEDTLS_AES_DECRYPT. + * \param input The buffer holding the input data. + * It must be readable and at least \c 16 Bytes long. + * \param output The buffer where the output data will be written. + * It must be writeable and at least \c 16 Bytes long. + + * \return \c 0 on success. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_crypt_ecb(mbedtls_aes_context *ctx, + int mode, + const unsigned char input[16], + unsigned char output[16]); + +#if defined(MBEDTLS_CIPHER_MODE_CBC) +/** + * \brief This function performs an AES-CBC encryption or decryption operation + * on full blocks. + * + * It performs the operation defined in the \p mode + * parameter (encrypt/decrypt), on the input data buffer defined in + * the \p input parameter. + * + * It can be called as many times as needed, until all the input + * data is processed. mbedtls_aes_init(), and either + * mbedtls_aes_setkey_enc() or mbedtls_aes_setkey_dec() must be called + * before the first call to this API with the same context. + * + * \note This function operates on full blocks, that is, the input size + * must be a multiple of the AES block size of \c 16 Bytes. + * + * \note Upon exit, the content of the IV is updated so that you can + * call the same function again on the next + * block(s) of data and get the same result as if it was + * encrypted in one call. This allows a "streaming" usage. + * If you need to retain the contents of the IV, you should + * either save it manually or use the cipher module instead. + * + * + * \param ctx The AES context to use for encryption or decryption. + * It must be initialized and bound to a key. + * \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or + * #MBEDTLS_AES_DECRYPT. + * \param length The length of the input data in Bytes. This must be a + * multiple of the block size (\c 16 Bytes). + * \param iv Initialization vector (updated after use). + * It must be a readable and writeable buffer of \c 16 Bytes. + * \param input The buffer holding the input data. + * It must be readable and of size \p length Bytes. + * \param output The buffer holding the output data. + * It must be writeable and of size \p length Bytes. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH + * on failure. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_crypt_cbc(mbedtls_aes_context *ctx, + int mode, + size_t length, + unsigned char iv[16], + const unsigned char *input, + unsigned char *output); +#endif /* MBEDTLS_CIPHER_MODE_CBC */ + +#if defined(MBEDTLS_CIPHER_MODE_XTS) +/** + * \brief This function performs an AES-XTS encryption or decryption + * operation for an entire XTS data unit. + * + * AES-XTS encrypts or decrypts blocks based on their location as + * defined by a data unit number. The data unit number must be + * provided by \p data_unit. + * + * NIST SP 800-38E limits the maximum size of a data unit to 2^20 + * AES blocks. If the data unit is larger than this, this function + * returns #MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH. + * + * \param ctx The AES XTS context to use for AES XTS operations. + * It must be initialized and bound to a key. + * \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or + * #MBEDTLS_AES_DECRYPT. + * \param length The length of a data unit in Bytes. This can be any + * length between 16 bytes and 2^24 bytes inclusive + * (between 1 and 2^20 block cipher blocks). + * \param data_unit The address of the data unit encoded as an array of 16 + * bytes in little-endian format. For disk encryption, this + * is typically the index of the block device sector that + * contains the data. + * \param input The buffer holding the input data (which is an entire + * data unit). This function reads \p length Bytes from \p + * input. + * \param output The buffer holding the output data (which is an entire + * data unit). This function writes \p length Bytes to \p + * output. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH if \p length is + * smaller than an AES block in size (16 Bytes) or if \p + * length is larger than 2^20 blocks (16 MiB). + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_crypt_xts(mbedtls_aes_xts_context *ctx, + int mode, + size_t length, + const unsigned char data_unit[16], + const unsigned char *input, + unsigned char *output); +#endif /* MBEDTLS_CIPHER_MODE_XTS */ + +#if defined(MBEDTLS_CIPHER_MODE_CFB) +/** + * \brief This function performs an AES-CFB128 encryption or decryption + * operation. + * + * It performs the operation defined in the \p mode + * parameter (encrypt or decrypt), on the input data buffer + * defined in the \p input parameter. + * + * For CFB, you must set up the context with mbedtls_aes_setkey_enc(), + * regardless of whether you are performing an encryption or decryption + * operation, that is, regardless of the \p mode parameter. This is + * because CFB mode uses the same key schedule for encryption and + * decryption. + * + * \note Upon exit, the content of the IV is updated so that you can + * call the same function again on the next + * block(s) of data and get the same result as if it was + * encrypted in one call. This allows a "streaming" usage. + * If you need to retain the contents of the + * IV, you must either save it manually or use the cipher + * module instead. + * + * + * \param ctx The AES context to use for encryption or decryption. + * It must be initialized and bound to a key. + * \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or + * #MBEDTLS_AES_DECRYPT. + * \param length The length of the input data in Bytes. + * \param iv_off The offset in IV (updated after use). + * It must point to a valid \c size_t. + * \param iv The initialization vector (updated after use). + * It must be a readable and writeable buffer of \c 16 Bytes. + * \param input The buffer holding the input data. + * It must be readable and of size \p length Bytes. + * \param output The buffer holding the output data. + * It must be writeable and of size \p length Bytes. + * + * \return \c 0 on success. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_crypt_cfb128(mbedtls_aes_context *ctx, + int mode, + size_t length, + size_t *iv_off, + unsigned char iv[16], + const unsigned char *input, + unsigned char *output); + +/** + * \brief This function performs an AES-CFB8 encryption or decryption + * operation. + * + * It performs the operation defined in the \p mode + * parameter (encrypt/decrypt), on the input data buffer defined + * in the \p input parameter. + * + * Due to the nature of CFB, you must use the same key schedule for + * both encryption and decryption operations. Therefore, you must + * use the context initialized with mbedtls_aes_setkey_enc() for + * both #MBEDTLS_AES_ENCRYPT and #MBEDTLS_AES_DECRYPT. + * + * \note Upon exit, the content of the IV is updated so that you can + * call the same function again on the next + * block(s) of data and get the same result as if it was + * encrypted in one call. This allows a "streaming" usage. + * If you need to retain the contents of the + * IV, you should either save it manually or use the cipher + * module instead. + * + * + * \param ctx The AES context to use for encryption or decryption. + * It must be initialized and bound to a key. + * \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or + * #MBEDTLS_AES_DECRYPT + * \param length The length of the input data. + * \param iv The initialization vector (updated after use). + * It must be a readable and writeable buffer of \c 16 Bytes. + * \param input The buffer holding the input data. + * It must be readable and of size \p length Bytes. + * \param output The buffer holding the output data. + * It must be writeable and of size \p length Bytes. + * + * \return \c 0 on success. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_crypt_cfb8(mbedtls_aes_context *ctx, + int mode, + size_t length, + unsigned char iv[16], + const unsigned char *input, + unsigned char *output); +#endif /*MBEDTLS_CIPHER_MODE_CFB */ + +#if defined(MBEDTLS_CIPHER_MODE_OFB) +/** + * \brief This function performs an AES-OFB (Output Feedback Mode) + * encryption or decryption operation. + * + * For OFB, you must set up the context with + * mbedtls_aes_setkey_enc(), regardless of whether you are + * performing an encryption or decryption operation. This is + * because OFB mode uses the same key schedule for encryption and + * decryption. + * + * The OFB operation is identical for encryption or decryption, + * therefore no operation mode needs to be specified. + * + * \note Upon exit, the content of iv, the Initialisation Vector, is + * updated so that you can call the same function again on the next + * block(s) of data and get the same result as if it was encrypted + * in one call. This allows a "streaming" usage, by initialising + * iv_off to 0 before the first call, and preserving its value + * between calls. + * + * For non-streaming use, the iv should be initialised on each call + * to a unique value, and iv_off set to 0 on each call. + * + * If you need to retain the contents of the initialisation vector, + * you must either save it manually or use the cipher module + * instead. + * + * \warning For the OFB mode, the initialisation vector must be unique + * every encryption operation. Reuse of an initialisation vector + * will compromise security. + * + * \param ctx The AES context to use for encryption or decryption. + * It must be initialized and bound to a key. + * \param length The length of the input data. + * \param iv_off The offset in IV (updated after use). + * It must point to a valid \c size_t. + * \param iv The initialization vector (updated after use). + * It must be a readable and writeable buffer of \c 16 Bytes. + * \param input The buffer holding the input data. + * It must be readable and of size \p length Bytes. + * \param output The buffer holding the output data. + * It must be writeable and of size \p length Bytes. + * + * \return \c 0 on success. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_crypt_ofb(mbedtls_aes_context *ctx, + size_t length, + size_t *iv_off, + unsigned char iv[16], + const unsigned char *input, + unsigned char *output); + +#endif /* MBEDTLS_CIPHER_MODE_OFB */ + +#if defined(MBEDTLS_CIPHER_MODE_CTR) +/** + * \brief This function performs an AES-CTR encryption or decryption + * operation. + * + * Due to the nature of CTR, you must use the same key schedule + * for both encryption and decryption operations. Therefore, you + * must use the context initialized with mbedtls_aes_setkey_enc() + * for both #MBEDTLS_AES_ENCRYPT and #MBEDTLS_AES_DECRYPT. + * + * \warning You must never reuse a nonce value with the same key. Doing so + * would void the encryption for the two messages encrypted with + * the same nonce and key. + * + * There are two common strategies for managing nonces with CTR: + * + * 1. You can handle everything as a single message processed over + * successive calls to this function. In that case, you want to + * set \p nonce_counter and \p nc_off to 0 for the first call, and + * then preserve the values of \p nonce_counter, \p nc_off and \p + * stream_block across calls to this function as they will be + * updated by this function. + * + * With this strategy, you must not encrypt more than 2**128 + * blocks of data with the same key. + * + * 2. You can encrypt separate messages by dividing the \p + * nonce_counter buffer in two areas: the first one used for a + * per-message nonce, handled by yourself, and the second one + * updated by this function internally. + * + * For example, you might reserve the first 12 bytes for the + * per-message nonce, and the last 4 bytes for internal use. In that + * case, before calling this function on a new message you need to + * set the first 12 bytes of \p nonce_counter to your chosen nonce + * value, the last 4 to 0, and \p nc_off to 0 (which will cause \p + * stream_block to be ignored). That way, you can encrypt at most + * 2**96 messages of up to 2**32 blocks each with the same key. + * + * The per-message nonce (or information sufficient to reconstruct + * it) needs to be communicated with the ciphertext and must be unique. + * The recommended way to ensure uniqueness is to use a message + * counter. An alternative is to generate random nonces, but this + * limits the number of messages that can be securely encrypted: + * for example, with 96-bit random nonces, you should not encrypt + * more than 2**32 messages with the same key. + * + * Note that for both strategies, sizes are measured in blocks and + * that an AES block is 16 bytes. + * + * \warning Upon return, \p stream_block contains sensitive data. Its + * content must not be written to insecure storage and should be + * securely discarded as soon as it's no longer needed. + * + * \param ctx The AES context to use for encryption or decryption. + * It must be initialized and bound to a key. + * \param length The length of the input data. + * \param nc_off The offset in the current \p stream_block, for + * resuming within the current cipher stream. The + * offset pointer should be 0 at the start of a stream. + * It must point to a valid \c size_t. + * \param nonce_counter The 128-bit nonce and counter. + * It must be a readable-writeable buffer of \c 16 Bytes. + * \param stream_block The saved stream block for resuming. This is + * overwritten by the function. + * It must be a readable-writeable buffer of \c 16 Bytes. + * \param input The buffer holding the input data. + * It must be readable and of size \p length Bytes. + * \param output The buffer holding the output data. + * It must be writeable and of size \p length Bytes. + * + * \return \c 0 on success. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_aes_crypt_ctr(mbedtls_aes_context *ctx, + size_t length, + size_t *nc_off, + unsigned char nonce_counter[16], + unsigned char stream_block[16], + const unsigned char *input, + unsigned char *output); +#endif /* MBEDTLS_CIPHER_MODE_CTR */ + +/** + * \brief Internal AES block encryption function. This is only + * exposed to allow overriding it using + * \c MBEDTLS_AES_ENCRYPT_ALT. + * + * \param ctx The AES context to use for encryption. + * \param input The plaintext block. + * \param output The output (ciphertext) block. + * + * \return \c 0 on success. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_internal_aes_encrypt(mbedtls_aes_context *ctx, + const unsigned char input[16], + unsigned char output[16]); + +/** + * \brief Internal AES block decryption function. This is only + * exposed to allow overriding it using see + * \c MBEDTLS_AES_DECRYPT_ALT. + * + * \param ctx The AES context to use for decryption. + * \param input The ciphertext block. + * \param output The output (plaintext) block. + * + * \return \c 0 on success. + */ +MBEDTLS_CHECK_RETURN_TYPICAL +int mbedtls_internal_aes_decrypt(mbedtls_aes_context *ctx, + const unsigned char input[16], + unsigned char output[16]); + +#if defined(MBEDTLS_SELF_TEST) +/** + * \brief Checkup routine. + * + * \return \c 0 on success. + * \return \c 1 on failure. + */ +MBEDTLS_CHECK_RETURN_CRITICAL +int mbedtls_aes_self_test(int verbose); + +#endif /* MBEDTLS_SELF_TEST */ + +#ifdef __cplusplus +} +#endif + +#endif /* aes.h */ -- cgit