Tristan Matthews | 0a329cc | 2013-07-17 13:20:14 -0400 | [diff] [blame] | 1 | /* |
| 2 | * xfm.h |
| 3 | * |
| 4 | * interface for abstract crypto transform |
| 5 | * |
| 6 | * David A. McGrew |
| 7 | * Cisco Systems, Inc. |
| 8 | */ |
| 9 | |
| 10 | #ifndef XFM_H |
| 11 | #define XFM_H |
| 12 | |
| 13 | #include "crypto_kernel.h" |
| 14 | #include "err.h" |
| 15 | |
| 16 | /** |
| 17 | * @defgroup Crypto Cryptography |
| 18 | * |
| 19 | * A simple interface to an abstract cryptographic transform that |
| 20 | * provides both confidentiality and message authentication. |
| 21 | * |
| 22 | * @{ |
| 23 | */ |
| 24 | |
| 25 | /** |
| 26 | * @brief applies a crypto transform |
| 27 | * |
| 28 | * The function pointer xfm_func_t points to a function that |
| 29 | * implements a crypto transform, and provides a uniform API for |
| 30 | * accessing crypto mechanisms. |
| 31 | * |
| 32 | * @param key location of secret key |
| 33 | * |
| 34 | * @param clear data to be authenticated only |
| 35 | * |
| 36 | * @param clear_len length of data to be authenticated only |
| 37 | * |
| 38 | * @param iv location to write the Initialization Vector (IV) |
| 39 | * |
| 40 | * @param protect location of the data to be encrypted and |
| 41 | * authenticated (before the function call), and the ciphertext |
| 42 | * and authentication tag (after the call) |
| 43 | * |
| 44 | * @param protected_len location of the length of the data to be |
| 45 | * encrypted and authenticated (before the function call), and the |
| 46 | * length of the ciphertext (after the call) |
| 47 | * |
| 48 | * @param auth_tag location to write auth tag |
| 49 | */ |
| 50 | |
| 51 | typedef err_status_t (*xfm_func_t) |
| 52 | (void *key, |
| 53 | void *clear, |
| 54 | unsigned clear_len, |
| 55 | void *iv, |
| 56 | void *protect, |
| 57 | unsigned *protected_len, |
| 58 | void *auth_tag |
| 59 | ); |
| 60 | |
| 61 | typedef |
| 62 | err_status_t (*xfm_inv_t) |
| 63 | (void *key, /* location of secret key */ |
| 64 | void *clear, /* data to be authenticated only */ |
| 65 | unsigned clear_len, /* length of data to be authenticated only */ |
| 66 | void *iv, /* location of iv */ |
| 67 | void *opaque, /* data to be decrypted and authenticated */ |
| 68 | unsigned *opaque_len, /* location of the length of data to be |
| 69 | * decrypted and authd (before and after) |
| 70 | */ |
| 71 | void *auth_tag /* location of auth tag */ |
| 72 | ); |
| 73 | |
| 74 | typedef struct xfm_ctx_t { |
| 75 | xfm_func_t func; |
| 76 | xfm_inv_t inv; |
| 77 | unsigned key_len; |
| 78 | unsigned iv_len; |
| 79 | unsigned auth_tag_len; |
| 80 | } xfm_ctx_t; |
| 81 | |
| 82 | typedef xfm_ctx_t *xfm_t; |
| 83 | |
| 84 | #define xfm_get_key_len(xfm) ((xfm)->key_len) |
| 85 | |
| 86 | #define xfm_get_iv_len(xfm) ((xfm)->iv_len) |
| 87 | |
| 88 | #define xfm_get_auth_tag_len(xfm) ((xfm)->auth_tag_len) |
| 89 | |
| 90 | |
| 91 | /* cryptoalgo - 5/28 */ |
| 92 | |
| 93 | typedef err_status_t (*cryptoalg_func_t) |
| 94 | (void *key, |
| 95 | void *clear, |
| 96 | unsigned clear_len, |
| 97 | void *iv, |
| 98 | void *opaque, |
| 99 | unsigned *opaque_len |
| 100 | ); |
| 101 | |
| 102 | typedef |
| 103 | err_status_t (*cryptoalg_inv_t) |
| 104 | (void *key, /* location of secret key */ |
| 105 | void *clear, /* data to be authenticated only */ |
| 106 | unsigned clear_len, /* length of data to be authenticated only */ |
| 107 | void *iv, /* location of iv */ |
| 108 | void *opaque, /* data to be decrypted and authenticated */ |
| 109 | unsigned *opaque_len /* location of the length of data to be |
| 110 | * decrypted and authd (before and after) |
| 111 | */ |
| 112 | ); |
| 113 | |
| 114 | typedef struct cryptoalg_ctx_t { |
| 115 | cryptoalg_func_t enc; |
| 116 | cryptoalg_inv_t dec; |
| 117 | unsigned key_len; |
| 118 | unsigned iv_len; |
| 119 | unsigned auth_tag_len; |
| 120 | unsigned max_expansion; |
| 121 | } cryptoalg_ctx_t; |
| 122 | |
| 123 | typedef cryptoalg_ctx_t *cryptoalg_t; |
| 124 | |
| 125 | #define cryptoalg_get_key_len(cryptoalg) ((cryptoalg)->key_len) |
| 126 | |
| 127 | #define cryptoalg_get_iv_len(cryptoalg) ((cryptoalg)->iv_len) |
| 128 | |
| 129 | #define cryptoalg_get_auth_tag_len(cryptoalg) ((cryptoalg)->auth_tag_len) |
| 130 | |
| 131 | |
| 132 | |
| 133 | /** |
| 134 | * @} |
| 135 | */ |
| 136 | |
| 137 | #endif /* XFM_H */ |
| 138 | |
| 139 | |