yuzu-emu/mbedtls
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Improve CCM documentation

Browse source 
- Rephrase function/parameter/enum/define/error descriptions into full and
  clear sentences.
- Make sure to adhering to the Arm writing guidelines.
- Fix missing/incorrect Doxygen tags.
- Standardize terminology used within the file.
- Fix iv_len values per the standard.

GitHub PR: #1305
This commit is contained in:
Rose Zadik 2018-01-24 12:56:53 +00:00 committed by Jaeden Amero
parent 7f44127c71
commit eecdbea30f
2 changed files with 72 additions and 58 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

128
include/mbedtls/ccm.h
View file

@ -1,10 +1,19 @@
/**
* \file ccm.h
*
* \brief Counter with CBC-MAC (CCM) for 128-bit block ciphers
* \brief CCM combines Counter mode encryption with CBC-MAC authentication
* for 128-bit block ciphers.
*
* Input to CCM includes the following elements:
* <ul><li>Payload - data that is both authenticated and encrypted.</li>
* <li>Associated data (Adata) - data that is authenticated but not
* encrypted, For example, a header.</li>
* <li>Nonce - A unique value that is assigned to the payload and the
* associated data.</li></ul>
*
*/
/*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
@ -19,16 +28,17 @@
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
* This file is part of Mbed TLS (https://tls.mbed.org)
*/
#ifndef MBEDTLS_CCM_H
#define MBEDTLS_CCM_H
#include "cipher.h"
#define MBEDTLS_ERR_CCM_BAD_INPUT -0x000D /**< Bad input parameters to function. */
#define MBEDTLS_ERR_CCM_AUTH_FAILED -0x000F /**< Authenticated decryption failed. */
#define MBEDTLS_ERR_CCM_HW_ACCEL_FAILED -0x0011 /**< CCM hardware accelerator failed. */
#define MBEDTLS_ERR_CCM_BAD_INPUT -0x000D /**< Bad input parameters to the function. */
#define MBEDTLS_ERR_CCM_AUTH_FAILED -0x000F /**< Authenticated decryption failed. */
#define MBEDTLS_ERR_CCM_HW_ACCEL_FAILED -0x0011 /**< CCM hardware accelerator failed. */
#if !defined(MBEDTLS_CCM_ALT)
// Regular implementation
@ -39,31 +49,33 @@ extern "C" {
#endif
/**
* \brief CCM context structure
* \brief The CCM context-type definition. The CCM context is passed
* to the APIs called.
*/
typedef struct {
mbedtls_cipher_context_t cipher_ctx; /*!< cipher context used */
mbedtls_cipher_context_t cipher_ctx; /*!< The cipher context used. */
}
mbedtls_ccm_context;
/**
* \brief Initialize CCM context (just makes references valid)
* Makes the context ready for mbedtls_ccm_setkey() or
* mbedtls_ccm_free().
* \brief This function initializes the specified CCM context,
* to make references valid, and prepare the context
* for mbedtls_ccm_setkey() or mbedtls_ccm_free().
*
* \param ctx CCM context to initialize
* \param ctx The CCM context to initialize.
*/
void mbedtls_ccm_init( mbedtls_ccm_context *ctx );
/**
* \brief CCM initialization (encryption and decryption)
* \brief This function initializes the CCM context set in the
* \p ctx parameter and sets the encryption key.
*
* \param ctx CCM context to be initialized
* \param cipher cipher to use (a 128-bit block cipher)
* \param key encryption key
* \param keybits key size in bits (must be acceptable by the cipher)
* \param ctx The CCM context to initialize.
* \param cipher The 128-bit block cipher to use.
* \param key The encryption key.
* \param keybits The key size in bits. This must be acceptable by the cipher.
*
* \return 0 if successful, or a cipher specific error code
* \return \c 0 on success, or a cipher-specific error code.
*/
int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
mbedtls_cipher_id_t cipher,
@ -71,36 +83,37 @@ int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
unsigned int keybits );
/**
* \brief Free a CCM context and underlying cipher sub-context
* \brief This function releases and clears the specified CCM context
* and underlying cipher sub-context.
*
* \param ctx CCM context to free
* \param ctx The CCM context to clear.
*/
void mbedtls_ccm_free( mbedtls_ccm_context *ctx );
/**
* \brief CCM buffer encryption
* \brief This function encrypts a buffer using CCM.
*
* \param ctx CCM context
* \param length length of the input data in bytes
* \param iv nonce (initialization vector)
* \param iv_len length of IV in bytes
* must be 2, 3, 4, 5, 6, 7 or 8
* \param add additional data
* \param add_len length of additional data in bytes
* must be less than 2^16 - 2^8
* \param input buffer holding the input data
* \param output buffer for holding the output data
* must be at least 'length' bytes wide
* \param tag buffer for holding the tag
* \param tag_len length of the tag to generate in bytes
* must be 4, 6, 8, 10, 14 or 16
* \param ctx The CCM context to use for encryption.
* \param length The length of the input data in Bytes.
* \param iv Initialization vector (nonce).
* \param iv_len The length of the IV in Bytes: 7, 8, 9, 10, 11, 12, or 13.
* \param add The additional data field.
* \param add_len The length of additional data in Bytes.
* Must be less than 2^16 - 2^8.
* \param input The buffer holding the input data.
* \param output The buffer holding the output data.
* Must be at least \p length Bytes wide.
* \param tag The buffer holding the tag.
* \param tag_len The length of the tag to generate in Bytes:
* 4, 6, 8, 10, 14 or 16.
*
* \note The tag is written to a separate buffer. To get the tag
* concatenated with the output as in the CCM spec, use
* tag = output + length and make sure the output buffer is
* at least length + tag_len wide.
* \note The tag is written to a separate buffer. To concatenate
* the \p tag with the \p output, as done in <em>RFC-3610:
* Counter with CBC-MAC (CCM)</em>, use
* \p tag = \p output + \p length, and make sure that the
* output buffer is at least \p length + \p tag_len wide.
*
* \return 0 if successful
* \return \c 0 on success.
*/
int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *iv, size_t iv_len,
@ -109,21 +122,22 @@ int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
unsigned char *tag, size_t tag_len );
/**
* \brief CCM buffer authenticated decryption
* \brief This function performs a CCM authenticated decryption of a
* buffer.
*
* \param ctx CCM context
* \param length length of the input data
* \param iv initialization vector
* \param iv_len length of IV
* \param add additional data
* \param add_len length of additional data
* \param input buffer holding the input data
* \param output buffer for holding the output data
* \param tag buffer holding the tag
* \param tag_len length of the tag
* \param ctx The CCM context to use for decryption.
* \param length The length of the input data in Bytes.
* \param iv Initialization vector.
* \param iv_len The length of the IV in Bytes: 7, 8, 9, 10, 11, 12, or 13.
* \param add The additional data field.
* \param add_len The length of additional data in Bytes.
* \param input The buffer holding the input data.
* \param output The buffer holding the output data.
* \param tag The buffer holding the tag.
* \param tag_len The length of the tag in Bytes.
*
* \return 0 if successful and authenticated,
* MBEDTLS_ERR_CCM_AUTH_FAILED if tag does not match
* \return 0 if successful and authenticated, or
* #MBEDTLS_ERR_CCM_AUTH_FAILED if the tag does not match.
*/
int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *iv, size_t iv_len,
@ -135,9 +149,9 @@ int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
}
#endif
#else /* !MBEDTLS_CCM_ALT */
#else /* MBEDTLS_CCM_ALT */
#include "ccm_alt.h"
#endif /* !MBEDTLS_CCM_ALT */
#endif /* MBEDTLS_CCM_ALT */
#ifdef __cplusplus
extern "C" {
@ -145,9 +159,9 @@ extern "C" {
#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
/**
* \brief Checkup routine
* \brief The CCM checkup routine.
*
* \return 0 if successful, or 1 if the test failed
* \return \c 0 on success, or \c 1 on failure.
*/
int mbedtls_ccm_self_test( int verbose );
#endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */

2
library/error.c
View file

@ -642,7 +642,7 @@ void mbedtls_strerror( int ret, char *buf, size_t buflen )
#if defined(MBEDTLS_CCM_C)
if( use_ret == -(MBEDTLS_ERR_CCM_BAD_INPUT) )
mbedtls_snprintf( buf, buflen, "CCM - Bad input parameters to function" );
mbedtls_snprintf( buf, buflen, "CCM - Bad input parameters to the function" );
if( use_ret == -(MBEDTLS_ERR_CCM_AUTH_FAILED) )
mbedtls_snprintf( buf, buflen, "CCM - Authenticated decryption failed" );
if( use_ret == -(MBEDTLS_ERR_CCM_HW_ACCEL_FAILED) )