1 /** 2 * \file arc4.h 3 * 4 * \brief The ARCFOUR stream cipher 5 * 6 * \warning ARC4 is considered a weak cipher and its use constitutes a 7 * security risk. We recommend considering stronger ciphers instead. 8 */ 9 /* 10 * Copyright The Mbed TLS Contributors 11 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later 12 * 13 */ 14 #ifndef MBEDTLS_ARC4_H 15 #define MBEDTLS_ARC4_H 16 17 #if !defined(MBEDTLS_CONFIG_FILE) 18 #include "mbedtls/config.h" 19 #else 20 #include MBEDTLS_CONFIG_FILE 21 #endif 22 23 #include <stddef.h> 24 25 /* MBEDTLS_ERR_ARC4_HW_ACCEL_FAILED is deprecated and should not be used. */ 26 /** ARC4 hardware accelerator failed. */ 27 #define MBEDTLS_ERR_ARC4_HW_ACCEL_FAILED -0x0019 28 29 #ifdef __cplusplus 30 extern "C" { 31 #endif 32 33 #if !defined(MBEDTLS_ARC4_ALT) 34 // Regular implementation 35 // 36 37 /** 38 * \brief ARC4 context structure 39 * 40 * \warning ARC4 is considered a weak cipher and its use constitutes a 41 * security risk. We recommend considering stronger ciphers instead. 42 * 43 */ 44 typedef struct mbedtls_arc4_context { 45 int x; /*!< permutation index */ 46 int y; /*!< permutation index */ 47 unsigned char m[256]; /*!< permutation table */ 48 } 49 mbedtls_arc4_context; 50 51 #else /* MBEDTLS_ARC4_ALT */ 52 #include "arc4_alt.h" 53 #endif /* MBEDTLS_ARC4_ALT */ 54 55 /** 56 * \brief Initialize ARC4 context 57 * 58 * \param ctx ARC4 context to be initialized 59 * 60 * \warning ARC4 is considered a weak cipher and its use constitutes a 61 * security risk. We recommend considering stronger ciphers 62 * instead. 63 * 64 */ 65 void mbedtls_arc4_init(mbedtls_arc4_context *ctx); 66 67 /** 68 * \brief Clear ARC4 context 69 * 70 * \param ctx ARC4 context to be cleared 71 * 72 * \warning ARC4 is considered a weak cipher and its use constitutes a 73 * security risk. We recommend considering stronger ciphers 74 * instead. 75 * 76 */ 77 void mbedtls_arc4_free(mbedtls_arc4_context *ctx); 78 79 /** 80 * \brief ARC4 key schedule 81 * 82 * \param ctx ARC4 context to be setup 83 * \param key the secret key 84 * \param keylen length of the key, in bytes 85 * 86 * \warning ARC4 is considered a weak cipher and its use constitutes a 87 * security risk. We recommend considering stronger ciphers 88 * instead. 89 * 90 */ 91 void mbedtls_arc4_setup(mbedtls_arc4_context *ctx, const unsigned char *key, 92 unsigned int keylen); 93 94 /** 95 * \brief ARC4 cipher function 96 * 97 * \param ctx ARC4 context 98 * \param length length of the input data 99 * \param input buffer holding the input data 100 * \param output buffer for the output data 101 * 102 * \return 0 if successful 103 * 104 * \warning ARC4 is considered a weak cipher and its use constitutes a 105 * security risk. We recommend considering stronger ciphers 106 * instead. 107 * 108 */ 109 int mbedtls_arc4_crypt(mbedtls_arc4_context *ctx, size_t length, const unsigned char *input, 110 unsigned char *output); 111 112 #if defined(MBEDTLS_SELF_TEST) 113 114 /** 115 * \brief Checkup routine 116 * 117 * \return 0 if successful, or 1 if the test failed 118 * 119 * \warning ARC4 is considered a weak cipher and its use constitutes a 120 * security risk. We recommend considering stronger ciphers 121 * instead. 122 * 123 */ 124 int mbedtls_arc4_self_test(int verbose); 125 126 #endif /* MBEDTLS_SELF_TEST */ 127 128 #ifdef __cplusplus 129 } 130 #endif 131 132 #endif /* arc4.h */ 133