1 /**************************************************************************/ 2 /* */ 3 /* Copyright (c) Microsoft Corporation. All rights reserved. */ 4 /* */ 5 /* This software is licensed under the Microsoft Software License */ 6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */ 7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */ 8 /* and in the root directory of this software. */ 9 /* */ 10 /**************************************************************************/ 11 12 13 /**************************************************************************/ 14 /**************************************************************************/ 15 /** */ 16 /** NetX Crypto Component */ 17 /** */ 18 /** Diffie-Hellman (DH) */ 19 /** */ 20 /**************************************************************************/ 21 /**************************************************************************/ 22 23 24 /**************************************************************************/ 25 /* */ 26 /* APPLICATION INTERFACE DEFINITION RELEASE */ 27 /* */ 28 /* nx_crypto_dh.h PORTABLE C */ 29 /* 6.1 */ 30 /* AUTHOR */ 31 /* */ 32 /* Timothy Stapko, Microsoft Corporation */ 33 /* */ 34 /* DESCRIPTION */ 35 /* */ 36 /* This file defines the basic Application Interface (API) to the */ 37 /* NetX Crypto DH module. */ 38 /* */ 39 /* RELEASE HISTORY */ 40 /* */ 41 /* DATE NAME DESCRIPTION */ 42 /* */ 43 /* 05-19-2020 Timothy Stapko Initial Version 6.0 */ 44 /* 09-30-2020 Timothy Stapko Modified comment(s), */ 45 /* resulting in version 6.1 */ 46 /* */ 47 /**************************************************************************/ 48 49 #ifndef NX_CRYPTO_DH_H 50 #define NX_CRYPTO_DH_H 51 52 /* Determine if a C++ compiler is being used. If so, ensure that standard 53 C is used to process the API information. */ 54 #ifdef __cplusplus 55 56 /* Yes, C++ compiler is present. Use standard C. */ 57 extern "C" { 58 59 #endif 60 61 #include "nx_crypto_huge_number.h" 62 63 64 /* Diffie-Hellman key size. Buffer size for calculations is twice the key size */ 65 #define NX_CRYPTO_DIFFIE_HELLMAN_GROUP_2_KEY_SIZE (128) /* 1024 bits/8. */ 66 #define NX_CRYPTO_DIFFIE_HELLMAN_MAX_KEY_SIZE (NX_CRYPTO_DIFFIE_HELLMAN_GROUP_2_KEY_SIZE) 67 68 /* Buffer and scratch buffer sizes are calculated from the maximum key size. */ 69 #define NX_CRYPTO_DIFFIE_HELLMAN_BUFFER_SIZE (NX_CRYPTO_DIFFIE_HELLMAN_MAX_KEY_SIZE * 4) 70 #define NX_CRYPTO_DIFFIE_HELLMAN_SCRATCH_SIZE (NX_CRYPTO_DIFFIE_HELLMAN_BUFFER_SIZE * 8) 71 72 /* Diffie-Hellman groups and key constants. */ 73 #define NX_CRYPTO_DH_GROUP_2_GENERATOR (0x2) /* Generator constant for Diffie-Hellman group 2. */ 74 75 #define NX_CRYPTO_DH_GROUP_2 (0x2) /* Standard DH group 2 for IPSEC. */ 76 #define NX_CRYPTO_DH_GROUP_TEST (0xFF) /* DH group used for testing. Note that this will only be valid in test builds. */ 77 78 /* Diffie-Hellman Key-exchange control structure. */ 79 typedef struct NX_CRYPTO_DH_STRUCT 80 { 81 /* The size of the key being used. This is primarily for testing, but also allows for future expansion. 82 The value is assigned in _nx_crypto_dh_setup depending on the chosen group. */ 83 UINT nx_crypto_dh_key_size; 84 85 /* The private key is generated by nx_crypto_dh_setup and is a random number. 86 During the computation, the private key is used as exponent. Therefore the buffer size is 87 the same as the key size. This number does not expand during the power-modulus computation. 88 Make the array in units of UINT to make sure the starting address is 4-byte aligned. */ 89 HN_UBASE nx_crypto_dh_private_key_buffer[NX_CRYPTO_DIFFIE_HELLMAN_MAX_KEY_SIZE >> HN_SIZE_SHIFT]; 90 91 /* The modulus, determined by the Diffie-Hellman group selected in the call to nx_crypto_dh_setup. 92 This number does not expand during the power-modulus computation. 93 Make the array in units of UINT to make sure the starting address is 4-byte aligned. */ 94 HN_UBASE *nx_crypto_dh_modulus; 95 } NX_CRYPTO_DH; 96 97 /* Function prototypes */ 98 99 100 UINT _nx_crypto_dh_setup(NX_CRYPTO_DH *dh_ptr, 101 UCHAR *local_public_key_ptr, 102 UINT *local_public_key_len_ptr, 103 ULONG dh_group_num, 104 HN_UBASE *scratch_buf_ptr); 105 106 UINT _nx_crypto_dh_compute_secret(NX_CRYPTO_DH *dh_ptr, 107 UCHAR *share_secret_key_ptr, 108 ULONG *share_secret_key_len_ptr, 109 UCHAR *remote_public_key, 110 ULONG remote_public_key_len, 111 HN_UBASE *scratch_buf_ptr); 112 113 #ifdef __cplusplus 114 } 115 #endif 116 117 #endif /* NX_CRYPTO_DH_H */ 118 119
