1 /** 2 * \file poly1305.h 3 * 4 * \brief This file contains Poly1305 definitions and functions. 5 * 6 * Poly1305 is a one-time message authenticator that can be used to 7 * authenticate messages. Poly1305-AES was created by Daniel 8 * Bernstein https://cr.yp.to/mac/poly1305-20050329.pdf The generic 9 * Poly1305 algorithm (not tied to AES) was also standardized in RFC 10 * 7539. 11 * 12 * \author Daniel King <damaki.gh@gmail.com> 13 */ 14 15 /* Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved. 16 * SPDX-License-Identifier: Apache-2.0 17 * 18 * Licensed under the Apache License, Version 2.0 (the "License"); you may 19 * not use this file except in compliance with the License. 20 * You may obtain a copy of the License at 21 * 22 * http://www.apache.org/licenses/LICENSE-2.0 23 * 24 * Unless required by applicable law or agreed to in writing, software 25 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 26 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 27 * See the License for the specific language governing permissions and 28 * limitations under the License. 29 * 30 * This file is part of Mbed TLS (https://tls.mbed.org) 31 */ 32 33 #ifndef MBEDTLS_POLY1305_H 34 #define MBEDTLS_POLY1305_H 35 36 #if !defined(MBEDTLS_CONFIG_FILE) 37 #include "mbedtls/config.h" 38 #else 39 #include MBEDTLS_CONFIG_FILE 40 #endif 41 42 #include <stdint.h> 43 #include <stddef.h> 44 45 #define MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA -0x0057 /**< Invalid input parameter(s). */ 46 47 /* MBEDTLS_ERR_POLY1305_FEATURE_UNAVAILABLE is deprecated and should not be 48 * used. */ 49 #define MBEDTLS_ERR_POLY1305_FEATURE_UNAVAILABLE -0x0059 /**< Feature not available. For example, s part of the API is not implemented. */ 50 51 /* MBEDTLS_ERR_POLY1305_HW_ACCEL_FAILED is deprecated and should not be used. 52 */ 53 #define MBEDTLS_ERR_POLY1305_HW_ACCEL_FAILED -0x005B /**< Poly1305 hardware accelerator failed. */ 54 55 #ifdef __cplusplus 56 extern "C" { 57 #endif 58 59 #if !defined(MBEDTLS_POLY1305_ALT) 60 61 typedef struct mbedtls_poly1305_context 62 { 63 uint32_t r[4]; /** The value for 'r' (low 128 bits of the key). */ 64 uint32_t s[4]; /** The value for 's' (high 128 bits of the key). */ 65 uint32_t acc[5]; /** The accumulator number. */ 66 uint8_t queue[16]; /** The current partial block of data. */ 67 size_t queue_len; /** The number of bytes stored in 'queue'. */ 68 } 69 mbedtls_poly1305_context; 70 71 #else /* MBEDTLS_POLY1305_ALT */ 72 #include "poly1305_alt.h" 73 #endif /* MBEDTLS_POLY1305_ALT */ 74 75 /** 76 * \brief This function initializes the specified Poly1305 context. 77 * 78 * It must be the first API called before using 79 * the context. 80 * 81 * It is usually followed by a call to 82 * \c mbedtls_poly1305_starts(), then one or more calls to 83 * \c mbedtls_poly1305_update(), then one call to 84 * \c mbedtls_poly1305_finish(), then finally 85 * \c mbedtls_poly1305_free(). 86 * 87 * \param ctx The Poly1305 context to initialize. This must 88 * not be \c NULL. 89 */ 90 void mbedtls_poly1305_init( mbedtls_poly1305_context *ctx ); 91 92 /** 93 * \brief This function releases and clears the specified 94 * Poly1305 context. 95 * 96 * \param ctx The Poly1305 context to clear. This may be \c NULL, in which 97 * case this function is a no-op. If it is not \c NULL, it must 98 * point to an initialized Poly1305 context. 99 */ 100 void mbedtls_poly1305_free( mbedtls_poly1305_context *ctx ); 101 102 /** 103 * \brief This function sets the one-time authentication key. 104 * 105 * \warning The key must be unique and unpredictable for each 106 * invocation of Poly1305. 107 * 108 * \param ctx The Poly1305 context to which the key should be bound. 109 * This must be initialized. 110 * \param key The buffer containing the \c 32 Byte (\c 256 Bit) key. 111 * 112 * \return \c 0 on success. 113 * \return A negative error code on failure. 114 */ 115 int mbedtls_poly1305_starts( mbedtls_poly1305_context *ctx, 116 const unsigned char key[32] ); 117 118 /** 119 * \brief This functions feeds an input buffer into an ongoing 120 * Poly1305 computation. 121 * 122 * It is called between \c mbedtls_cipher_poly1305_starts() and 123 * \c mbedtls_cipher_poly1305_finish(). 124 * It can be called repeatedly to process a stream of data. 125 * 126 * \param ctx The Poly1305 context to use for the Poly1305 operation. 127 * This must be initialized and bound to a key. 128 * \param ilen The length of the input data in Bytes. 129 * Any value is accepted. 130 * \param input The buffer holding the input data. 131 * This pointer can be \c NULL if `ilen == 0`. 132 * 133 * \return \c 0 on success. 134 * \return A negative error code on failure. 135 */ 136 int mbedtls_poly1305_update( mbedtls_poly1305_context *ctx, 137 const unsigned char *input, 138 size_t ilen ); 139 140 /** 141 * \brief This function generates the Poly1305 Message 142 * Authentication Code (MAC). 143 * 144 * \param ctx The Poly1305 context to use for the Poly1305 operation. 145 * This must be initialized and bound to a key. 146 * \param mac The buffer to where the MAC is written. This must 147 * be a writable buffer of length \c 16 Bytes. 148 * 149 * \return \c 0 on success. 150 * \return A negative error code on failure. 151 */ 152 int mbedtls_poly1305_finish( mbedtls_poly1305_context *ctx, 153 unsigned char mac[16] ); 154 155 /** 156 * \brief This function calculates the Poly1305 MAC of the input 157 * buffer with the provided key. 158 * 159 * \warning The key must be unique and unpredictable for each 160 * invocation of Poly1305. 161 * 162 * \param key The buffer containing the \c 32 Byte (\c 256 Bit) key. 163 * \param ilen The length of the input data in Bytes. 164 * Any value is accepted. 165 * \param input The buffer holding the input data. 166 * This pointer can be \c NULL if `ilen == 0`. 167 * \param mac The buffer to where the MAC is written. This must be 168 * a writable buffer of length \c 16 Bytes. 169 * 170 * \return \c 0 on success. 171 * \return A negative error code on failure. 172 */ 173 int mbedtls_poly1305_mac( const unsigned char key[32], 174 const unsigned char *input, 175 size_t ilen, 176 unsigned char mac[16] ); 177 178 #if defined(MBEDTLS_SELF_TEST) 179 /** 180 * \brief The Poly1305 checkup routine. 181 * 182 * \return \c 0 on success. 183 * \return \c 1 on failure. 184 */ 185 int mbedtls_poly1305_self_test( int verbose ); 186 #endif /* MBEDTLS_SELF_TEST */ 187 188 #ifdef __cplusplus 189 } 190 #endif 191 192 #endif /* MBEDTLS_POLY1305_H */ 193