1 /** 2 * \file ccm.h 3 * 4 * \brief Counter with CBC-MAC (CCM) for 128-bit block ciphers 5 * 6 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved 7 * SPDX-License-Identifier: Apache-2.0 8 * 9 * Licensed under the Apache License, Version 2.0 (the "License"); you may 10 * not use this file except in compliance with the License. 11 * You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 17 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 * 21 * This file is part of mbed TLS (https://tls.mbed.org) 22 */ 23 #ifndef MBEDTLS_CCM_H 24 #define MBEDTLS_CCM_H 25 26 #include "cipher.h" 27 28 #define MBEDTLS_ERR_CCM_BAD_INPUT -0x000D /**< Bad input parameters to function. */ 29 #define MBEDTLS_ERR_CCM_AUTH_FAILED -0x000F /**< Authenticated decryption failed. */ 30 31 #ifdef __cplusplus 32 extern "C" { 33 #endif 34 35 /** 36 * \brief CCM context structure 37 */ 38 typedef struct { 39 mbedtls_cipher_context_t cipher_ctx; /*!< cipher context used */ 40 } 41 mbedtls_ccm_context; 42 43 /** 44 * \brief Initialize CCM context (just makes references valid) 45 * Makes the context ready for mbedtls_ccm_setkey() or 46 * mbedtls_ccm_free(). 47 * 48 * \param ctx CCM context to initialize 49 */ 50 void mbedtls_ccm_init( mbedtls_ccm_context *ctx ); 51 52 /** 53 * \brief CCM initialization (encryption and decryption) 54 * 55 * \param ctx CCM context to be initialized 56 * \param cipher cipher to use (a 128-bit block cipher) 57 * \param key encryption key 58 * \param keybits key size in bits (must be acceptable by the cipher) 59 * 60 * \return 0 if successful, or a cipher specific error code 61 */ 62 int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx, 63 mbedtls_cipher_id_t cipher, 64 const unsigned char *key, 65 unsigned int keybits ); 66 67 /** 68 * \brief Free a CCM context and underlying cipher sub-context 69 * 70 * \param ctx CCM context to free 71 */ 72 void mbedtls_ccm_free( mbedtls_ccm_context *ctx ); 73 74 /** 75 * \brief CCM buffer encryption 76 * 77 * \param ctx CCM context 78 * \param length length of the input data in bytes 79 * \param iv nonce (initialization vector) 80 * \param iv_len length of IV in bytes 81 * must be 2, 3, 4, 5, 6, 7 or 8 82 * \param add additional data 83 * \param add_len length of additional data in bytes 84 * must be less than 2^16 - 2^8 85 * \param input buffer holding the input data 86 * \param output buffer for holding the output data 87 * must be at least 'length' bytes wide 88 * \param tag buffer for holding the tag 89 * \param tag_len length of the tag to generate in bytes 90 * must be 4, 6, 8, 10, 14 or 16 91 * 92 * \note The tag is written to a separate buffer. To get the tag 93 * concatenated with the output as in the CCM spec, use 94 * tag = output + length and make sure the output buffer is 95 * at least length + tag_len wide. 96 * 97 * \return 0 if successful 98 */ 99 int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length, 100 const unsigned char *iv, size_t iv_len, 101 const unsigned char *add, size_t add_len, 102 const unsigned char *input, unsigned char *output, 103 unsigned char *tag, size_t tag_len ); 104 105 /** 106 * \brief CCM buffer authenticated decryption 107 * 108 * \param ctx CCM context 109 * \param length length of the input data 110 * \param iv initialization vector 111 * \param iv_len length of IV 112 * \param add additional data 113 * \param add_len length of additional data 114 * \param input buffer holding the input data 115 * \param output buffer for holding the output data 116 * \param tag buffer holding the tag 117 * \param tag_len length of the tag 118 * 119 * \return 0 if successful and authenticated, 120 * MBEDTLS_ERR_CCM_AUTH_FAILED if tag does not match 121 */ 122 int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length, 123 const unsigned char *iv, size_t iv_len, 124 const unsigned char *add, size_t add_len, 125 const unsigned char *input, unsigned char *output, 126 const unsigned char *tag, size_t tag_len ); 127 128 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C) 129 /** 130 * \brief Checkup routine 131 * 132 * \return 0 if successful, or 1 if the test failed 133 */ 134 int mbedtls_ccm_self_test( int verbose ); 135 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */ 136 137 #ifdef __cplusplus 138 } 139 #endif 140 141 #endif /* MBEDTLS_CCM_H */ 142
