1 /** 2 * \file aria.h 3 * 4 * \brief ARIA block cipher 5 * 6 * The ARIA algorithm is a symmetric block cipher that can encrypt and 7 * decrypt information. It is defined by the Korean Agency for 8 * Technology and Standards (KATS) in <em>KS X 1213:2004</em> (in 9 * Korean, but see http://210.104.33.10/ARIA/index-e.html in English) 10 * and also described by the IETF in <em>RFC 5794</em>. 11 */ 12 /* 13 * Copyright The Mbed TLS Contributors 14 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later 15 */ 16 17 #ifndef MBEDTLS_ARIA_H 18 #define MBEDTLS_ARIA_H 19 #include "mbedtls/private_access.h" 20 21 #include "mbedtls/build_info.h" 22 23 #include <stddef.h> 24 #include <stdint.h> 25 26 #include "mbedtls/platform_util.h" 27 28 #define MBEDTLS_ARIA_ENCRYPT 1 /**< ARIA encryption. */ 29 #define MBEDTLS_ARIA_DECRYPT 0 /**< ARIA decryption. */ 30 31 #define MBEDTLS_ARIA_BLOCKSIZE 16 /**< ARIA block size in bytes. */ 32 #define MBEDTLS_ARIA_MAX_ROUNDS 16 /**< Maximum number of rounds in ARIA. */ 33 #define MBEDTLS_ARIA_MAX_KEYSIZE 32 /**< Maximum size of an ARIA key in bytes. */ 34 35 /** Bad input data. */ 36 #define MBEDTLS_ERR_ARIA_BAD_INPUT_DATA -0x005C 37 38 /** Invalid data input length. */ 39 #define MBEDTLS_ERR_ARIA_INVALID_INPUT_LENGTH -0x005E 40 41 #ifdef __cplusplus 42 extern "C" { 43 #endif 44 45 #if !defined(MBEDTLS_ARIA_ALT) 46 // Regular implementation 47 // 48 49 /** 50 * \brief The ARIA context-type definition. 51 */ 52 typedef struct mbedtls_aria_context { 53 unsigned char MBEDTLS_PRIVATE(nr); /*!< The number of rounds (12, 14 or 16) */ 54 /*! The ARIA round keys. */ 55 uint32_t MBEDTLS_PRIVATE(rk)[MBEDTLS_ARIA_MAX_ROUNDS + 1][MBEDTLS_ARIA_BLOCKSIZE / 4]; 56 } 57 mbedtls_aria_context; 58 59 #else /* MBEDTLS_ARIA_ALT */ 60 #include "aria_alt.h" 61 #endif /* MBEDTLS_ARIA_ALT */ 62 63 /** 64 * \brief This function initializes the specified ARIA context. 65 * 66 * It must be the first API called before using 67 * the context. 68 * 69 * \param ctx The ARIA context to initialize. This must not be \c NULL. 70 */ 71 void mbedtls_aria_init(mbedtls_aria_context *ctx); 72 73 /** 74 * \brief This function releases and clears the specified ARIA context. 75 * 76 * \param ctx The ARIA context to clear. This may be \c NULL, in which 77 * case this function returns immediately. If it is not \c NULL, 78 * it must point to an initialized ARIA context. 79 */ 80 void mbedtls_aria_free(mbedtls_aria_context *ctx); 81 82 /** 83 * \brief This function sets the encryption key. 84 * 85 * \param ctx The ARIA context to which the key should be bound. 86 * This must be initialized. 87 * \param key The encryption key. This must be a readable buffer 88 * of size \p keybits Bits. 89 * \param keybits The size of \p key in Bits. Valid options are: 90 * <ul><li>128 bits</li> 91 * <li>192 bits</li> 92 * <li>256 bits</li></ul> 93 * 94 * \return \c 0 on success. 95 * \return A negative error code on failure. 96 */ 97 int mbedtls_aria_setkey_enc(mbedtls_aria_context *ctx, 98 const unsigned char *key, 99 unsigned int keybits); 100 101 /** 102 * \brief This function sets the decryption key. 103 * 104 * \param ctx The ARIA context to which the key should be bound. 105 * This must be initialized. 106 * \param key The decryption key. This must be a readable buffer 107 * of size \p keybits Bits. 108 * \param keybits The size of data passed. Valid options are: 109 * <ul><li>128 bits</li> 110 * <li>192 bits</li> 111 * <li>256 bits</li></ul> 112 * 113 * \return \c 0 on success. 114 * \return A negative error code on failure. 115 */ 116 int mbedtls_aria_setkey_dec(mbedtls_aria_context *ctx, 117 const unsigned char *key, 118 unsigned int keybits); 119 120 /** 121 * \brief This function performs an ARIA single-block encryption or 122 * decryption operation. 123 * 124 * It performs encryption or decryption (depending on whether 125 * the key was set for encryption on decryption) on the input 126 * data buffer defined in the \p input parameter. 127 * 128 * mbedtls_aria_init(), and either mbedtls_aria_setkey_enc() or 129 * mbedtls_aria_setkey_dec() must be called before the first 130 * call to this API with the same context. 131 * 132 * \param ctx The ARIA context to use for encryption or decryption. 133 * This must be initialized and bound to a key. 134 * \param input The 16-Byte buffer holding the input data. 135 * \param output The 16-Byte buffer holding the output data. 136 137 * \return \c 0 on success. 138 * \return A negative error code on failure. 139 */ 140 int mbedtls_aria_crypt_ecb(mbedtls_aria_context *ctx, 141 const unsigned char input[MBEDTLS_ARIA_BLOCKSIZE], 142 unsigned char output[MBEDTLS_ARIA_BLOCKSIZE]); 143 144 #if defined(MBEDTLS_CIPHER_MODE_CBC) 145 /** 146 * \brief This function performs an ARIA-CBC encryption or decryption operation 147 * on full blocks. 148 * 149 * It performs the operation defined in the \p mode 150 * parameter (encrypt/decrypt), on the input data buffer defined in 151 * the \p input parameter. 152 * 153 * It can be called as many times as needed, until all the input 154 * data is processed. mbedtls_aria_init(), and either 155 * mbedtls_aria_setkey_enc() or mbedtls_aria_setkey_dec() must be called 156 * before the first call to this API with the same context. 157 * 158 * \note This function operates on aligned blocks, that is, the input size 159 * must be a multiple of the ARIA block size of 16 Bytes. 160 * 161 * \note Upon exit, the content of the IV is updated so that you can 162 * call the same function again on the next 163 * block(s) of data and get the same result as if it was 164 * encrypted in one call. This allows a "streaming" usage. 165 * If you need to retain the contents of the IV, you should 166 * either save it manually or use the cipher module instead. 167 * 168 * 169 * \param ctx The ARIA context to use for encryption or decryption. 170 * This must be initialized and bound to a key. 171 * \param mode The mode of operation. This must be either 172 * #MBEDTLS_ARIA_ENCRYPT for encryption, or 173 * #MBEDTLS_ARIA_DECRYPT for decryption. 174 * \param length The length of the input data in Bytes. This must be a 175 * multiple of the block size (16 Bytes). 176 * \param iv Initialization vector (updated after use). 177 * This must be a readable buffer of size 16 Bytes. 178 * \param input The buffer holding the input data. This must 179 * be a readable buffer of length \p length Bytes. 180 * \param output The buffer holding the output data. This must 181 * be a writable buffer of length \p length Bytes. 182 * 183 * \return \c 0 on success. 184 * \return A negative error code on failure. 185 */ 186 int mbedtls_aria_crypt_cbc(mbedtls_aria_context *ctx, 187 int mode, 188 size_t length, 189 unsigned char iv[MBEDTLS_ARIA_BLOCKSIZE], 190 const unsigned char *input, 191 unsigned char *output); 192 #endif /* MBEDTLS_CIPHER_MODE_CBC */ 193 194 #if defined(MBEDTLS_CIPHER_MODE_CFB) 195 /** 196 * \brief This function performs an ARIA-CFB128 encryption or decryption 197 * operation. 198 * 199 * It performs the operation defined in the \p mode 200 * parameter (encrypt or decrypt), on the input data buffer 201 * defined in the \p input parameter. 202 * 203 * For CFB, you must set up the context with mbedtls_aria_setkey_enc(), 204 * regardless of whether you are performing an encryption or decryption 205 * operation, that is, regardless of the \p mode parameter. This is 206 * because CFB mode uses the same key schedule for encryption and 207 * decryption. 208 * 209 * \note Upon exit, the content of the IV is updated so that you can 210 * call the same function again on the next 211 * block(s) of data and get the same result as if it was 212 * encrypted in one call. This allows a "streaming" usage. 213 * If you need to retain the contents of the 214 * IV, you must either save it manually or use the cipher 215 * module instead. 216 * 217 * 218 * \param ctx The ARIA context to use for encryption or decryption. 219 * This must be initialized and bound to a key. 220 * \param mode The mode of operation. This must be either 221 * #MBEDTLS_ARIA_ENCRYPT for encryption, or 222 * #MBEDTLS_ARIA_DECRYPT for decryption. 223 * \param length The length of the input data \p input in Bytes. 224 * \param iv_off The offset in IV (updated after use). 225 * This must not be larger than 15. 226 * \param iv The initialization vector (updated after use). 227 * This must be a readable buffer of size 16 Bytes. 228 * \param input The buffer holding the input data. This must 229 * be a readable buffer of length \p length Bytes. 230 * \param output The buffer holding the output data. This must 231 * be a writable buffer of length \p length Bytes. 232 * 233 * \return \c 0 on success. 234 * \return A negative error code on failure. 235 */ 236 int mbedtls_aria_crypt_cfb128(mbedtls_aria_context *ctx, 237 int mode, 238 size_t length, 239 size_t *iv_off, 240 unsigned char iv[MBEDTLS_ARIA_BLOCKSIZE], 241 const unsigned char *input, 242 unsigned char *output); 243 #endif /* MBEDTLS_CIPHER_MODE_CFB */ 244 245 #if defined(MBEDTLS_CIPHER_MODE_CTR) 246 /** 247 * \brief This function performs an ARIA-CTR encryption or decryption 248 * operation. 249 * 250 * Due to the nature of CTR, you must use the same key schedule 251 * for both encryption and decryption operations. Therefore, you 252 * must use the context initialized with mbedtls_aria_setkey_enc() 253 * for both #MBEDTLS_ARIA_ENCRYPT and #MBEDTLS_ARIA_DECRYPT. 254 * 255 * \warning You must never reuse a nonce value with the same key. Doing so 256 * would void the encryption for the two messages encrypted with 257 * the same nonce and key. 258 * 259 * There are two common strategies for managing nonces with CTR: 260 * 261 * 1. You can handle everything as a single message processed over 262 * successive calls to this function. In that case, you want to 263 * set \p nonce_counter and \p nc_off to 0 for the first call, and 264 * then preserve the values of \p nonce_counter, \p nc_off and \p 265 * stream_block across calls to this function as they will be 266 * updated by this function. 267 * 268 * With this strategy, you must not encrypt more than 2**128 269 * blocks of data with the same key. 270 * 271 * 2. You can encrypt separate messages by dividing the \p 272 * nonce_counter buffer in two areas: the first one used for a 273 * per-message nonce, handled by yourself, and the second one 274 * updated by this function internally. 275 * 276 * For example, you might reserve the first 12 bytes for the 277 * per-message nonce, and the last 4 bytes for internal use. In that 278 * case, before calling this function on a new message you need to 279 * set the first 12 bytes of \p nonce_counter to your chosen nonce 280 * value, the last 4 to 0, and \p nc_off to 0 (which will cause \p 281 * stream_block to be ignored). That way, you can encrypt at most 282 * 2**96 messages of up to 2**32 blocks each with the same key. 283 * 284 * The per-message nonce (or information sufficient to reconstruct 285 * it) needs to be communicated with the ciphertext and must be unique. 286 * The recommended way to ensure uniqueness is to use a message 287 * counter. An alternative is to generate random nonces, but this 288 * limits the number of messages that can be securely encrypted: 289 * for example, with 96-bit random nonces, you should not encrypt 290 * more than 2**32 messages with the same key. 291 * 292 * Note that for both strategies, sizes are measured in blocks and 293 * that an ARIA block is 16 bytes. 294 * 295 * \warning Upon return, \p stream_block contains sensitive data. Its 296 * content must not be written to insecure storage and should be 297 * securely discarded as soon as it's no longer needed. 298 * 299 * \param ctx The ARIA context to use for encryption or decryption. 300 * This must be initialized and bound to a key. 301 * \param length The length of the input data \p input in Bytes. 302 * \param nc_off The offset in Bytes in the current \p stream_block, 303 * for resuming within the current cipher stream. The 304 * offset pointer should be \c 0 at the start of a 305 * stream. This must not be larger than \c 15 Bytes. 306 * \param nonce_counter The 128-bit nonce and counter. This must point to 307 * a read/write buffer of length \c 16 bytes. 308 * \param stream_block The saved stream block for resuming. This must 309 * point to a read/write buffer of length \c 16 bytes. 310 * This is overwritten by the function. 311 * \param input The buffer holding the input data. This must 312 * be a readable buffer of length \p length Bytes. 313 * \param output The buffer holding the output data. This must 314 * be a writable buffer of length \p length Bytes. 315 * 316 * \return \c 0 on success. 317 * \return A negative error code on failure. 318 */ 319 int mbedtls_aria_crypt_ctr(mbedtls_aria_context *ctx, 320 size_t length, 321 size_t *nc_off, 322 unsigned char nonce_counter[MBEDTLS_ARIA_BLOCKSIZE], 323 unsigned char stream_block[MBEDTLS_ARIA_BLOCKSIZE], 324 const unsigned char *input, 325 unsigned char *output); 326 #endif /* MBEDTLS_CIPHER_MODE_CTR */ 327 328 #if defined(MBEDTLS_SELF_TEST) 329 /** 330 * \brief Checkup routine. 331 * 332 * \return \c 0 on success, or \c 1 on failure. 333 */ 334 int mbedtls_aria_self_test(int verbose); 335 #endif /* MBEDTLS_SELF_TEST */ 336 337 #ifdef __cplusplus 338 } 339 #endif 340 341 #endif /* aria.h */ 342
