626 lines
22 KiB
C
626 lines
22 KiB
C
/**
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* \file cipher.h
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*
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* \brief Generic cipher wrapper.
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*
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* \author Adriaan de Jong <dejong@fox-it.com>
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*
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* Copyright (C) 2006-2013, Brainspark B.V.
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*
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* This file is part of PolarSSL (http://www.polarssl.org)
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* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
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*
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* All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#ifndef POLARSSL_CIPHER_H
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#define POLARSSL_CIPHER_H
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#include "config.h"
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#if defined(POLARSSL_GCM_C)
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#define POLARSSL_CIPHER_MODE_AEAD
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#endif
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#if defined(POLARSSL_CIPHER_MODE_CBC)
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#define POLARSSL_CIPHER_MODE_WITH_PADDING
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#endif
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#include <string.h>
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#if defined(_MSC_VER) && !defined(inline)
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#define inline _inline
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#else
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#if defined(__ARMCC_VERSION) && !defined(inline)
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#define inline __inline
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#endif /* __ARMCC_VERSION */
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#endif /*_MSC_VER */
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#define POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE -0x6080 /**< The selected feature is not available. */
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#define POLARSSL_ERR_CIPHER_BAD_INPUT_DATA -0x6100 /**< Bad input parameters to function. */
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#define POLARSSL_ERR_CIPHER_ALLOC_FAILED -0x6180 /**< Failed to allocate memory. */
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#define POLARSSL_ERR_CIPHER_INVALID_PADDING -0x6200 /**< Input data contains invalid padding and is rejected. */
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#define POLARSSL_ERR_CIPHER_FULL_BLOCK_EXPECTED -0x6280 /**< Decryption of block requires a full block. */
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#define POLARSSL_ERR_CIPHER_AUTH_FAILED -0x6300 /**< Authentication failed (for AEAD modes). */
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#ifdef __cplusplus
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extern "C" {
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#endif
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typedef enum {
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POLARSSL_CIPHER_ID_NONE = 0,
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POLARSSL_CIPHER_ID_NULL,
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POLARSSL_CIPHER_ID_AES,
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POLARSSL_CIPHER_ID_DES,
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POLARSSL_CIPHER_ID_3DES,
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POLARSSL_CIPHER_ID_CAMELLIA,
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POLARSSL_CIPHER_ID_BLOWFISH,
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POLARSSL_CIPHER_ID_ARC4,
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} cipher_id_t;
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typedef enum {
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POLARSSL_CIPHER_NONE = 0,
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POLARSSL_CIPHER_NULL,
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POLARSSL_CIPHER_AES_128_ECB,
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POLARSSL_CIPHER_AES_192_ECB,
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POLARSSL_CIPHER_AES_256_ECB,
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POLARSSL_CIPHER_AES_128_CBC,
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POLARSSL_CIPHER_AES_192_CBC,
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POLARSSL_CIPHER_AES_256_CBC,
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POLARSSL_CIPHER_AES_128_CFB128,
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POLARSSL_CIPHER_AES_192_CFB128,
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POLARSSL_CIPHER_AES_256_CFB128,
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POLARSSL_CIPHER_AES_128_CTR,
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POLARSSL_CIPHER_AES_192_CTR,
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POLARSSL_CIPHER_AES_256_CTR,
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POLARSSL_CIPHER_AES_128_GCM,
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POLARSSL_CIPHER_AES_192_GCM,
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POLARSSL_CIPHER_AES_256_GCM,
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POLARSSL_CIPHER_CAMELLIA_128_ECB,
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POLARSSL_CIPHER_CAMELLIA_192_ECB,
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POLARSSL_CIPHER_CAMELLIA_256_ECB,
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POLARSSL_CIPHER_CAMELLIA_128_CBC,
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POLARSSL_CIPHER_CAMELLIA_192_CBC,
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POLARSSL_CIPHER_CAMELLIA_256_CBC,
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POLARSSL_CIPHER_CAMELLIA_128_CFB128,
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POLARSSL_CIPHER_CAMELLIA_192_CFB128,
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POLARSSL_CIPHER_CAMELLIA_256_CFB128,
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POLARSSL_CIPHER_CAMELLIA_128_CTR,
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POLARSSL_CIPHER_CAMELLIA_192_CTR,
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POLARSSL_CIPHER_CAMELLIA_256_CTR,
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POLARSSL_CIPHER_DES_ECB,
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POLARSSL_CIPHER_DES_CBC,
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POLARSSL_CIPHER_DES_EDE_ECB,
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POLARSSL_CIPHER_DES_EDE_CBC,
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POLARSSL_CIPHER_DES_EDE3_ECB,
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POLARSSL_CIPHER_DES_EDE3_CBC,
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POLARSSL_CIPHER_BLOWFISH_ECB,
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POLARSSL_CIPHER_BLOWFISH_CBC,
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POLARSSL_CIPHER_BLOWFISH_CFB64,
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POLARSSL_CIPHER_BLOWFISH_CTR,
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POLARSSL_CIPHER_ARC4_128,
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} cipher_type_t;
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typedef enum {
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POLARSSL_MODE_NONE = 0,
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POLARSSL_MODE_ECB,
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POLARSSL_MODE_CBC,
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POLARSSL_MODE_CFB,
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POLARSSL_MODE_OFB,
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POLARSSL_MODE_CTR,
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POLARSSL_MODE_GCM,
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POLARSSL_MODE_STREAM,
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} cipher_mode_t;
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typedef enum {
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POLARSSL_PADDING_PKCS7 = 0, /**< PKCS7 padding (default) */
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POLARSSL_PADDING_ONE_AND_ZEROS, /**< ISO/IEC 7816-4 padding */
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POLARSSL_PADDING_ZEROS_AND_LEN, /**< ANSI X.923 padding */
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POLARSSL_PADDING_ZEROS, /**< zero padding (not reversible!) */
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POLARSSL_PADDING_NONE, /**< never pad (full blocks only) */
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} cipher_padding_t;
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typedef enum {
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POLARSSL_OPERATION_NONE = -1,
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POLARSSL_DECRYPT = 0,
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POLARSSL_ENCRYPT,
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} operation_t;
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enum {
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/** Undefined key length */
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POLARSSL_KEY_LENGTH_NONE = 0,
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/** Key length, in bits (including parity), for DES keys */
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POLARSSL_KEY_LENGTH_DES = 64,
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/** Key length, in bits (including parity), for DES in two key EDE */
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POLARSSL_KEY_LENGTH_DES_EDE = 128,
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/** Key length, in bits (including parity), for DES in three-key EDE */
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POLARSSL_KEY_LENGTH_DES_EDE3 = 192,
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/** Maximum length of any IV, in bytes */
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POLARSSL_MAX_IV_LENGTH = 16,
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};
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/**
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* Base cipher information. The non-mode specific functions and values.
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*/
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typedef struct {
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/** Base Cipher type (e.g. POLARSSL_CIPHER_ID_AES) */
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cipher_id_t cipher;
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/** Encrypt using ECB */
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int (*ecb_func)( void *ctx, operation_t mode,
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const unsigned char *input, unsigned char *output );
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/** Encrypt using CBC */
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int (*cbc_func)( void *ctx, operation_t mode, size_t length, unsigned char *iv,
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const unsigned char *input, unsigned char *output );
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/** Encrypt using CFB (Full length) */
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int (*cfb_func)( void *ctx, operation_t mode, size_t length, size_t *iv_off,
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unsigned char *iv, const unsigned char *input, unsigned char *output );
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/** Encrypt using CTR */
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int (*ctr_func)( void *ctx, size_t length, size_t *nc_off, unsigned char *nonce_counter,
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unsigned char *stream_block, const unsigned char *input, unsigned char *output );
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/** Encrypt using STREAM */
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int (*stream_func)( void *ctx, size_t length,
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const unsigned char *input, unsigned char *output );
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/** Set key for encryption purposes */
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int (*setkey_enc_func)( void *ctx, const unsigned char *key, unsigned int key_length);
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/** Set key for decryption purposes */
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int (*setkey_dec_func)( void *ctx, const unsigned char *key, unsigned int key_length);
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/** Allocate a new context */
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void * (*ctx_alloc_func)( void );
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/** Free the given context */
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void (*ctx_free_func)( void *ctx );
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} cipher_base_t;
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/**
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* Cipher information. Allows cipher functions to be called in a generic way.
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*/
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typedef struct {
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/** Full cipher identifier (e.g. POLARSSL_CIPHER_AES_256_CBC) */
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cipher_type_t type;
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/** Cipher mode (e.g. POLARSSL_MODE_CBC) */
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cipher_mode_t mode;
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/** Cipher key length, in bits (default length for variable sized ciphers)
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* (Includes parity bits for ciphers like DES) */
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unsigned int key_length;
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/** Name of the cipher */
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const char * name;
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/** IV/NONCE size, in bytes.
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* For cipher that accept many sizes: recommended size */
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unsigned int iv_size;
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/** Flag for ciphers that accept many sizes of IV/NONCE */
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int accepts_variable_iv_size;
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/** block size, in bytes */
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unsigned int block_size;
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/** Base cipher information and functions */
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const cipher_base_t *base;
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} cipher_info_t;
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/**
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* Generic cipher context.
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*/
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typedef struct {
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/** Information about the associated cipher */
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const cipher_info_t *cipher_info;
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/** Key length to use */
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int key_length;
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/** Operation that the context's key has been initialised for */
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operation_t operation;
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/** Padding functions to use, if relevant for cipher mode */
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void (*add_padding)( unsigned char *output, size_t olen, size_t data_len );
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int (*get_padding)( unsigned char *input, size_t ilen, size_t *data_len );
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/** Buffer for data that hasn't been encrypted yet */
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unsigned char unprocessed_data[POLARSSL_MAX_IV_LENGTH];
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/** Number of bytes that still need processing */
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size_t unprocessed_len;
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/** Current IV or NONCE_COUNTER for CTR-mode */
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unsigned char iv[POLARSSL_MAX_IV_LENGTH];
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/** IV size in bytes (for ciphers with variable-length IVs) */
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size_t iv_size;
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/** Cipher-specific context */
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void *cipher_ctx;
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} cipher_context_t;
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/**
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* \brief Returns the list of ciphers supported by the generic cipher module.
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*
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* \return a statically allocated array of ciphers, the last entry
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* is 0.
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*/
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const int *cipher_list( void );
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/**
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* \brief Returns the cipher information structure associated
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* with the given cipher name.
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*
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* \param cipher_name Name of the cipher to search for.
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*
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* \return the cipher information structure associated with the
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* given cipher_name, or NULL if not found.
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*/
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const cipher_info_t *cipher_info_from_string( const char *cipher_name );
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/**
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* \brief Returns the cipher information structure associated
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* with the given cipher type.
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*
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* \param cipher_type Type of the cipher to search for.
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*
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* \return the cipher information structure associated with the
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* given cipher_type, or NULL if not found.
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*/
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const cipher_info_t *cipher_info_from_type( const cipher_type_t cipher_type );
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/**
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* \brief Returns the cipher information structure associated
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* with the given cipher id, key size and mode.
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*
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* \param cipher_id Id of the cipher to search for
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* (e.g. POLARSSL_CIPHER_ID_AES)
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* \param key_length Length of the key in bits
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* \param mode Cipher mode (e.g. POLARSSL_MODE_CBC)
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*
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* \return the cipher information structure associated with the
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* given cipher_type, or NULL if not found.
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*/
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const cipher_info_t *cipher_info_from_values( const cipher_id_t cipher_id,
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int key_length,
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const cipher_mode_t mode );
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/**
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* \brief Initialises and fills the cipher context structure with
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* the appropriate values.
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*
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* \param ctx context to initialise. May not be NULL.
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* \param cipher_info cipher to use.
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*
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* \return \c 0 on success,
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* \c POLARSSL_ERR_CIPHER_BAD_INPUT_DATA on parameter failure,
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* \c POLARSSL_ERR_CIPHER_ALLOC_FAILED if allocation of the
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* cipher-specific context failed.
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*/
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int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info );
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/**
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* \brief Free the cipher-specific context of ctx. Freeing ctx
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* itself remains the responsibility of the caller.
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*
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* \param ctx Free the cipher-specific context
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*
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* \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if
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* parameter verification fails.
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*/
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int cipher_free_ctx( cipher_context_t *ctx );
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/**
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* \brief Returns the block size of the given cipher.
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*
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* \param ctx cipher's context. Must have been initialised.
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*
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* \return size of the cipher's blocks, or 0 if ctx has not been
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* initialised.
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*/
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static inline unsigned int cipher_get_block_size( const cipher_context_t *ctx )
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{
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if( NULL == ctx || NULL == ctx->cipher_info )
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return 0;
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return ctx->cipher_info->block_size;
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}
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/**
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* \brief Returns the mode of operation for the cipher.
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* (e.g. POLARSSL_MODE_CBC)
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*
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* \param ctx cipher's context. Must have been initialised.
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*
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* \return mode of operation, or POLARSSL_MODE_NONE if ctx
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* has not been initialised.
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*/
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static inline cipher_mode_t cipher_get_cipher_mode( const cipher_context_t *ctx )
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{
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if( NULL == ctx || NULL == ctx->cipher_info )
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return POLARSSL_MODE_NONE;
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return ctx->cipher_info->mode;
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}
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/**
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* \brief Returns the size of the cipher's IV/NONCE in bytes.
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*
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* \param ctx cipher's context. Must have been initialised.
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*
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* \return If IV has not been set yet: (recommended) IV size
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* (0 for ciphers not using IV/NONCE).
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* If IV has already been set: actual size.
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*/
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static inline int cipher_get_iv_size( const cipher_context_t *ctx )
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{
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if( NULL == ctx || NULL == ctx->cipher_info )
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return 0;
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if( ctx->iv_size != 0 )
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return ctx->iv_size;
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return ctx->cipher_info->iv_size;
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}
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/**
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* \brief Returns the type of the given cipher.
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*
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* \param ctx cipher's context. Must have been initialised.
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*
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* \return type of the cipher, or POLARSSL_CIPHER_NONE if ctx has
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* not been initialised.
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*/
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static inline cipher_type_t cipher_get_type( const cipher_context_t *ctx )
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{
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if( NULL == ctx || NULL == ctx->cipher_info )
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return POLARSSL_CIPHER_NONE;
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return ctx->cipher_info->type;
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}
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/**
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* \brief Returns the name of the given cipher, as a string.
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*
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* \param ctx cipher's context. Must have been initialised.
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*
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* \return name of the cipher, or NULL if ctx was not initialised.
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*/
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static inline const char *cipher_get_name( const cipher_context_t *ctx )
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{
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if( NULL == ctx || NULL == ctx->cipher_info )
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return 0;
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return ctx->cipher_info->name;
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}
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/**
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* \brief Returns the key length of the cipher.
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*
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* \param ctx cipher's context. Must have been initialised.
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*
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* \return cipher's key length, in bits, or
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* POLARSSL_KEY_LENGTH_NONE if ctx has not been
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* initialised.
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*/
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static inline int cipher_get_key_size ( const cipher_context_t *ctx )
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{
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if( NULL == ctx || NULL == ctx->cipher_info )
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return POLARSSL_KEY_LENGTH_NONE;
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return ctx->cipher_info->key_length;
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}
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/**
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* \brief Returns the operation of the given cipher.
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*
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* \param ctx cipher's context. Must have been initialised.
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*
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* \return operation (POLARSSL_ENCRYPT or POLARSSL_DECRYPT),
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* or POLARSSL_OPERATION_NONE if ctx has not been
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* initialised.
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*/
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static inline operation_t cipher_get_operation( const cipher_context_t *ctx )
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{
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if( NULL == ctx || NULL == ctx->cipher_info )
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return POLARSSL_OPERATION_NONE;
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return ctx->operation;
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}
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/**
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* \brief Set the key to use with the given context.
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*
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* \param ctx generic cipher context. May not be NULL. Must have been
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* initialised using cipher_context_from_type or
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* cipher_context_from_string.
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* \param key The key to use.
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* \param key_length key length to use, in bits.
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* \param operation Operation that the key will be used for, either
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* POLARSSL_ENCRYPT or POLARSSL_DECRYPT.
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*
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* \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if
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* parameter verification fails or a cipher specific
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* error code.
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*/
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int cipher_setkey( cipher_context_t *ctx, const unsigned char *key, int key_length,
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const operation_t operation );
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#if defined(POLARSSL_CIPHER_MODE_WITH_PADDING)
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/**
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* \brief Set padding mode, for cipher modes that use padding.
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* (Default: PKCS7 padding.)
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*
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* \param ctx generic cipher context
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* \param mode padding mode
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*
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* \returns 0 on success, POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE
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* if selected padding mode is not supported, or
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* POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if the cipher mode
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* does not support padding.
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*/
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int cipher_set_padding_mode( cipher_context_t *ctx, cipher_padding_t mode );
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#endif /* POLARSSL_CIPHER_MODE_WITH_PADDING */
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/**
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* \brief Set the initialization vector (IV) or nonce
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*
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* \param ctx generic cipher context
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* \param iv IV to use (or NONCE_COUNTER for CTR-mode ciphers)
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* \param iv_len IV length for ciphers with variable-size IV;
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* discarded by ciphers with fixed-size IV.
|
|
*
|
|
* \returns O on success, or POLARSSL_ERR_CIPHER_BAD_INPUT_DATA
|
|
*
|
|
* \note Some ciphers don't use IVs nor NONCE. For these
|
|
* ciphers, this function has no effect.
|
|
*/
|
|
int cipher_set_iv( cipher_context_t *ctx,
|
|
const unsigned char *iv, size_t iv_len );
|
|
|
|
/**
|
|
* \brief Finish preparation of the given context
|
|
*
|
|
* \param ctx generic cipher context
|
|
*
|
|
* \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA
|
|
* if parameter verification fails.
|
|
*/
|
|
int cipher_reset( cipher_context_t *ctx );
|
|
|
|
#if defined(POLARSSL_CIPHER_MODE_AEAD)
|
|
/**
|
|
* \brief Add additional data (for AEAD ciphers).
|
|
* This function has no effect for non-AEAD ciphers.
|
|
* For AEAD ciphers, it may or may not be called
|
|
* repeatedly, and/or interleaved with calls to
|
|
* cipher_udpate(), depending on the cipher.
|
|
* E.g. for GCM is must be called exactly once, right
|
|
* after cipher_reset().
|
|
*
|
|
* \param ctx generic cipher context
|
|
* \param ad Additional data to use.
|
|
* \param ad_len Length of ad.
|
|
*
|
|
* \returns 0 on success, or a specific error code.
|
|
*/
|
|
int cipher_update_ad( cipher_context_t *ctx,
|
|
const unsigned char *ad, size_t ad_len );
|
|
#endif /* POLARSSL_CIPHER_MODE_AEAD */
|
|
|
|
/**
|
|
* \brief Generic cipher update function. Encrypts/decrypts
|
|
* using the given cipher context. Writes as many block
|
|
* size'd blocks of data as possible to output. Any data
|
|
* that cannot be written immediately will either be added
|
|
* to the next block, or flushed when cipher_final is
|
|
* called.
|
|
* Exception: for POLARSSL_MODE_ECB, expects single block
|
|
* in size (e.g. 16 bytes for AES)
|
|
*
|
|
* \param ctx generic cipher context
|
|
* \param input buffer holding the input data
|
|
* \param ilen length of the input data
|
|
* \param output buffer for the output data. Should be able to hold at
|
|
* least ilen + block_size. Cannot be the same buffer as
|
|
* input!
|
|
* \param olen length of the output data, will be filled with the
|
|
* actual number of bytes written.
|
|
*
|
|
* \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if
|
|
* parameter verification fails,
|
|
* POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE on an
|
|
* unsupported mode for a cipher or a cipher specific
|
|
* error code.
|
|
*
|
|
* \note If the underlying cipher is GCM, all calls to this
|
|
* function, except the last one before cipher_finish(),
|
|
* must have ilen a multiple of the block size.
|
|
*/
|
|
int cipher_update( cipher_context_t *ctx, const unsigned char *input, size_t ilen,
|
|
unsigned char *output, size_t *olen );
|
|
|
|
/**
|
|
* \brief Generic cipher finalisation function. If data still
|
|
* needs to be flushed from an incomplete block, data
|
|
* contained within it will be padded with the size of
|
|
* the last block, and written to the output buffer.
|
|
*
|
|
* \param ctx Generic cipher context
|
|
* \param output buffer to write data to. Needs block_size available.
|
|
* \param olen length of the data written to the output buffer.
|
|
*
|
|
* \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if
|
|
* parameter verification fails,
|
|
* POLARSSL_ERR_CIPHER_FULL_BLOCK_EXPECTED if decryption
|
|
* expected a full block but was not provided one,
|
|
* POLARSSL_ERR_CIPHER_INVALID_PADDING on invalid padding
|
|
* while decrypting or a cipher specific error code.
|
|
*/
|
|
int cipher_finish( cipher_context_t *ctx,
|
|
unsigned char *output, size_t *olen );
|
|
|
|
#if defined(POLARSSL_CIPHER_MODE_AEAD)
|
|
/**
|
|
* \brief Write tag for AEAD ciphers.
|
|
* No effect for other ciphers.
|
|
* Must be called after cipher_finish().
|
|
*
|
|
* \param ctx Generic cipher context
|
|
* \param tag buffer to write the tag
|
|
* \param tag_len Length of the tag to write
|
|
*
|
|
* \return 0 on success, or a specific error code.
|
|
*/
|
|
int cipher_write_tag( cipher_context_t *ctx,
|
|
unsigned char *tag, size_t tag_len );
|
|
|
|
/**
|
|
* \brief Check tag for AEAD ciphers.
|
|
* No effect for other ciphers.
|
|
* Calling time depends on the cipher:
|
|
* for GCM, must be called after cipher_finish().
|
|
*
|
|
* \param ctx Generic cipher context
|
|
* \param tag Buffer holding the tag
|
|
* \param tag_len Length of the tag to check
|
|
*
|
|
* \return 0 on success, or a specific error code.
|
|
*/
|
|
int cipher_check_tag( cipher_context_t *ctx,
|
|
const unsigned char *tag, size_t tag_len );
|
|
#endif /* POLARSSL_CIPHER_MODE_AEAD */
|
|
|
|
/**
|
|
* \brief Checkup routine
|
|
*
|
|
* \return 0 if successful, or 1 if the test failed
|
|
*/
|
|
int cipher_self_test( int verbose );
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* POLARSSL_CIPHER_H */
|