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Diffstat (limited to 'include/mbedtls/gcm.h')
-rw-r--r-- | include/mbedtls/gcm.h | 370 |
1 files changed, 0 insertions, 370 deletions
diff --git a/include/mbedtls/gcm.h b/include/mbedtls/gcm.h deleted file mode 100644 index 837cecc..0000000 --- a/include/mbedtls/gcm.h +++ /dev/null @@ -1,370 +0,0 @@ -/** - * \file gcm.h - * - * \brief This file contains GCM definitions and functions. - * - * The Galois/Counter Mode (GCM) for 128-bit block ciphers is defined - * in <em>D. McGrew, J. Viega, The Galois/Counter Mode of Operation - * (GCM), Natl. Inst. Stand. Technol.</em> - * - * For more information on GCM, see <em>NIST SP 800-38D: Recommendation for - * Block Cipher Modes of Operation: Galois/Counter Mode (GCM) and GMAC</em>. - * - */ -/* - * Copyright The Mbed TLS Contributors - * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later - */ - -#ifndef MBEDTLS_GCM_H -#define MBEDTLS_GCM_H -#include "mbedtls/private_access.h" - -#include "mbedtls/build_info.h" - -#include "mbedtls/cipher.h" - -#include <stdint.h> - -#define MBEDTLS_GCM_ENCRYPT 1 -#define MBEDTLS_GCM_DECRYPT 0 - -/** Authenticated decryption failed. */ -#define MBEDTLS_ERR_GCM_AUTH_FAILED -0x0012 -/** Bad input parameters to function. */ -#define MBEDTLS_ERR_GCM_BAD_INPUT -0x0014 -/** An output buffer is too small. */ -#define MBEDTLS_ERR_GCM_BUFFER_TOO_SMALL -0x0016 - -#ifdef __cplusplus -extern "C" { -#endif - -#if !defined(MBEDTLS_GCM_ALT) - -/** - * \brief The GCM context structure. - */ -typedef struct mbedtls_gcm_context { - mbedtls_cipher_context_t MBEDTLS_PRIVATE(cipher_ctx); /*!< The cipher context used. */ - uint64_t MBEDTLS_PRIVATE(HL)[16]; /*!< Precalculated HTable low. */ - uint64_t MBEDTLS_PRIVATE(HH)[16]; /*!< Precalculated HTable high. */ - uint64_t MBEDTLS_PRIVATE(len); /*!< The total length of the encrypted data. */ - uint64_t MBEDTLS_PRIVATE(add_len); /*!< The total length of the additional data. */ - unsigned char MBEDTLS_PRIVATE(base_ectr)[16]; /*!< The first ECTR for tag. */ - unsigned char MBEDTLS_PRIVATE(y)[16]; /*!< The Y working value. */ - unsigned char MBEDTLS_PRIVATE(buf)[16]; /*!< The buf working value. */ - int MBEDTLS_PRIVATE(mode); /*!< The operation to perform: - #MBEDTLS_GCM_ENCRYPT or - #MBEDTLS_GCM_DECRYPT. */ -} -mbedtls_gcm_context; - -#else /* !MBEDTLS_GCM_ALT */ -#include "gcm_alt.h" -#endif /* !MBEDTLS_GCM_ALT */ - -/** - * \brief This function initializes the specified GCM context, - * to make references valid, and prepares the context - * for mbedtls_gcm_setkey() or mbedtls_gcm_free(). - * - * The function does not bind the GCM context to a particular - * cipher, nor set the key. For this purpose, use - * mbedtls_gcm_setkey(). - * - * \param ctx The GCM context to initialize. This must not be \c NULL. - */ -void mbedtls_gcm_init(mbedtls_gcm_context *ctx); - -/** - * \brief This function associates a GCM context with a - * cipher algorithm and a key. - * - * \param ctx The GCM context. This must be initialized. - * \param cipher The 128-bit block cipher to use. - * \param key The encryption key. This must be a readable buffer of at - * least \p keybits bits. - * \param keybits The key size in bits. Valid options are: - * <ul><li>128 bits</li> - * <li>192 bits</li> - * <li>256 bits</li></ul> - * - * \return \c 0 on success. - * \return A cipher-specific error code on failure. - */ -int mbedtls_gcm_setkey(mbedtls_gcm_context *ctx, - mbedtls_cipher_id_t cipher, - const unsigned char *key, - unsigned int keybits); - -/** - * \brief This function performs GCM encryption or decryption of a buffer. - * - * \note For encryption, the output buffer can be the same as the - * input buffer. For decryption, the output buffer cannot be - * the same as input buffer. If the buffers overlap, the output - * buffer must trail at least 8 Bytes behind the input buffer. - * - * \warning When this function performs a decryption, it outputs the - * authentication tag and does not verify that the data is - * authentic. You should use this function to perform encryption - * only. For decryption, use mbedtls_gcm_auth_decrypt() instead. - * - * \param ctx The GCM context to use for encryption or decryption. This - * must be initialized. - * \param mode The operation to perform: - * - #MBEDTLS_GCM_ENCRYPT to perform authenticated encryption. - * The ciphertext is written to \p output and the - * authentication tag is written to \p tag. - * - #MBEDTLS_GCM_DECRYPT to perform decryption. - * The plaintext is written to \p output and the - * authentication tag is written to \p tag. - * Note that this mode is not recommended, because it does - * not verify the authenticity of the data. For this reason, - * you should use mbedtls_gcm_auth_decrypt() instead of - * calling this function in decryption mode. - * \param length The length of the input data, which is equal to the length - * of the output data. - * \param iv The initialization vector. This must be a readable buffer of - * at least \p iv_len Bytes. - * \param iv_len The length of the IV. - * \param add The buffer holding the additional data. This must be of at - * least that size in Bytes. - * \param add_len The length of the additional data. - * \param input The buffer holding the input data. If \p length is greater - * than zero, this must be a readable buffer of at least that - * size in Bytes. - * \param output The buffer for holding the output data. If \p length is greater - * than zero, this must be a writable buffer of at least that - * size in Bytes. - * \param tag_len The length of the tag to generate. - * \param tag The buffer for holding the tag. This must be a writable - * buffer of at least \p tag_len Bytes. - * - * \return \c 0 if the encryption or decryption was performed - * successfully. Note that in #MBEDTLS_GCM_DECRYPT mode, - * this does not indicate that the data is authentic. - * \return #MBEDTLS_ERR_GCM_BAD_INPUT if the lengths or pointers are - * not valid or a cipher-specific error code if the encryption - * or decryption failed. - */ -int mbedtls_gcm_crypt_and_tag(mbedtls_gcm_context *ctx, - int mode, - size_t length, - const unsigned char *iv, - size_t iv_len, - const unsigned char *add, - size_t add_len, - const unsigned char *input, - unsigned char *output, - size_t tag_len, - unsigned char *tag); - -/** - * \brief This function performs a GCM authenticated decryption of a - * buffer. - * - * \note For decryption, the output buffer cannot be the same as - * input buffer. If the buffers overlap, the output buffer - * must trail at least 8 Bytes behind the input buffer. - * - * \param ctx The GCM context. This must be initialized. - * \param length The length of the ciphertext to decrypt, which is also - * the length of the decrypted plaintext. - * \param iv The initialization vector. This must be a readable buffer - * of at least \p iv_len Bytes. - * \param iv_len The length of the IV. - * \param add The buffer holding the additional data. This must be of at - * least that size in Bytes. - * \param add_len The length of the additional data. - * \param tag The buffer holding the tag to verify. This must be a - * readable buffer of at least \p tag_len Bytes. - * \param tag_len The length of the tag to verify. - * \param input The buffer holding the ciphertext. If \p length is greater - * than zero, this must be a readable buffer of at least that - * size. - * \param output The buffer for holding the decrypted plaintext. If \p length - * is greater than zero, this must be a writable buffer of at - * least that size. - * - * \return \c 0 if successful and authenticated. - * \return #MBEDTLS_ERR_GCM_AUTH_FAILED if the tag does not match. - * \return #MBEDTLS_ERR_GCM_BAD_INPUT if the lengths or pointers are - * not valid or a cipher-specific error code if the decryption - * failed. - */ -int mbedtls_gcm_auth_decrypt(mbedtls_gcm_context *ctx, - size_t length, - const unsigned char *iv, - size_t iv_len, - const unsigned char *add, - size_t add_len, - const unsigned char *tag, - size_t tag_len, - const unsigned char *input, - unsigned char *output); - -/** - * \brief This function starts a GCM encryption or decryption - * operation. - * - * \param ctx The GCM context. This must be initialized. - * \param mode The operation to perform: #MBEDTLS_GCM_ENCRYPT or - * #MBEDTLS_GCM_DECRYPT. - * \param iv The initialization vector. This must be a readable buffer of - * at least \p iv_len Bytes. - * \param iv_len The length of the IV. - * - * \return \c 0 on success. - */ -int mbedtls_gcm_starts(mbedtls_gcm_context *ctx, - int mode, - const unsigned char *iv, - size_t iv_len); - -/** - * \brief This function feeds an input buffer as associated data - * (authenticated but not encrypted data) in a GCM - * encryption or decryption operation. - * - * Call this function after mbedtls_gcm_starts() to pass - * the associated data. If the associated data is empty, - * you do not need to call this function. You may not - * call this function after calling mbedtls_cipher_update(). - * - * \param ctx The GCM context. This must have been started with - * mbedtls_gcm_starts() and must not have yet received - * any input with mbedtls_gcm_update(). - * \param add The buffer holding the additional data, or \c NULL - * if \p add_len is \c 0. - * \param add_len The length of the additional data. If \c 0, - * \p add may be \c NULL. - * - * \return \c 0 on success. - */ -int mbedtls_gcm_update_ad(mbedtls_gcm_context *ctx, - const unsigned char *add, - size_t add_len); - -/** - * \brief This function feeds an input buffer into an ongoing GCM - * encryption or decryption operation. - * - * You may call this function zero, one or more times - * to pass successive parts of the input: the plaintext to - * encrypt, or the ciphertext (not including the tag) to - * decrypt. After the last part of the input, call - * mbedtls_gcm_finish(). - * - * This function may produce output in one of the following - * ways: - * - Immediate output: the output length is always equal - * to the input length. - * - Buffered output: the output consists of a whole number - * of 16-byte blocks. If the total input length so far - * (not including associated data) is 16 \* *B* + *A* - * with *A* < 16 then the total output length is 16 \* *B*. - * - * In particular: - * - It is always correct to call this function with - * \p output_size >= \p input_length + 15. - * - If \p input_length is a multiple of 16 for all the calls - * to this function during an operation, then it is - * correct to use \p output_size = \p input_length. - * - * \note For decryption, the output buffer cannot be the same as - * input buffer. If the buffers overlap, the output buffer - * must trail at least 8 Bytes behind the input buffer. - * - * \param ctx The GCM context. This must be initialized. - * \param input The buffer holding the input data. If \p input_length - * is greater than zero, this must be a readable buffer - * of at least \p input_length bytes. - * \param input_length The length of the input data in bytes. - * \param output The buffer for the output data. If \p output_size - * is greater than zero, this must be a writable buffer of - * of at least \p output_size bytes. - * \param output_size The size of the output buffer in bytes. - * See the function description regarding the output size. - * \param output_length On success, \p *output_length contains the actual - * length of the output written in \p output. - * On failure, the content of \p *output_length is - * unspecified. - * - * \return \c 0 on success. - * \return #MBEDTLS_ERR_GCM_BAD_INPUT on failure: - * total input length too long, - * unsupported input/output buffer overlap detected, - * or \p output_size too small. - */ -int mbedtls_gcm_update(mbedtls_gcm_context *ctx, - const unsigned char *input, size_t input_length, - unsigned char *output, size_t output_size, - size_t *output_length); - -/** - * \brief This function finishes the GCM operation and generates - * the authentication tag. - * - * It wraps up the GCM stream, and generates the - * tag. The tag can have a maximum length of 16 Bytes. - * - * \param ctx The GCM context. This must be initialized. - * \param tag The buffer for holding the tag. This must be a writable - * buffer of at least \p tag_len Bytes. - * \param tag_len The length of the tag to generate. This must be at least - * four. - * \param output The buffer for the final output. - * If \p output_size is nonzero, this must be a writable - * buffer of at least \p output_size bytes. - * \param output_size The size of the \p output buffer in bytes. - * This must be large enough for the output that - * mbedtls_gcm_update() has not produced. In particular: - * - If mbedtls_gcm_update() produces immediate output, - * or if the total input size is a multiple of \c 16, - * then mbedtls_gcm_finish() never produces any output, - * so \p output_size can be \c 0. - * - \p output_size never needs to be more than \c 15. - * \param output_length On success, \p *output_length contains the actual - * length of the output written in \p output. - * On failure, the content of \p *output_length is - * unspecified. - * - * \return \c 0 on success. - * \return #MBEDTLS_ERR_GCM_BAD_INPUT on failure: - * invalid value of \p tag_len, - * or \p output_size too small. - */ -int mbedtls_gcm_finish(mbedtls_gcm_context *ctx, - unsigned char *output, size_t output_size, - size_t *output_length, - unsigned char *tag, size_t tag_len); - -/** - * \brief This function clears a GCM context and the underlying - * cipher sub-context. - * - * \param ctx The GCM context to clear. If this is \c NULL, the call has - * no effect. Otherwise, this must be initialized. - */ -void mbedtls_gcm_free(mbedtls_gcm_context *ctx); - -#if defined(MBEDTLS_SELF_TEST) - -/** - * \brief The GCM checkup routine. - * - * \return \c 0 on success. - * \return \c 1 on failure. - */ -int mbedtls_gcm_self_test(int verbose); - -#endif /* MBEDTLS_SELF_TEST */ - -#ifdef __cplusplus -} -#endif - - -#endif /* gcm.h */ |