1 /* 2 Copyright (c) 2023 Assa Abloy. See the COPYRIGHT 3 file at the top-level directory of this distribution. 4 5 Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or 6 http://www.apache.org/licenses/LICENSE-2.0> or the MIT license 7 <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your 8 option. This file may not be copied, modified, or distributed 9 except according to those terms. 10 */ 11 12 #ifndef OSCORE_INTERACTIONS_H 13 #define OSCORE_INTERACTIONS_H 14 15 #include <stdint.h> 16 #include "oscore/oscore_coap_defines.h" 17 #include "common/byte_array.h" 18 #include "common/oscore_edhoc_error.h" 19 20 /** 21 * @brief Number of interactions supported at the same time, per one OSCORE context. 22 */ 23 #ifndef OSCORE_INTERACTIONS_COUNT 24 #define OSCORE_INTERACTIONS_COUNT 3 25 #endif 26 27 /** 28 * @brief Single record of interaction between the server and the client. 29 */ 30 struct oscore_interaction_t { 31 /* Request type, used to distinguish between normal request and resource observations. */ 32 enum o_coap_msg request_type; 33 34 /* CoAP token of the subscription request. */ 35 uint8_t token[MAX_TOKEN_LEN]; 36 uint8_t token_len; 37 38 /* Full URI path (all options concatenated to single string). */ 39 uint8_t uri_paths[OSCORE_MAX_URI_PATH_LEN]; 40 uint8_t uri_paths_len; 41 42 /* PIV of the subscription request. */ 43 uint8_t request_piv[MAX_PIV_LEN]; 44 uint8_t request_piv_len; 45 46 /* KID of the subscription request. */ 47 uint8_t request_kid[MAX_KID_LEN]; 48 uint8_t request_kid_len; 49 50 /* True if given record is occupied (used in interactions array). */ 51 bool is_occupied; 52 }; 53 54 /** 55 * @brief Initialize interactions array. 56 * 57 * @param interactions Interactions array, MUST have exactly OSCORE_INTERACTIONS_COUNT elements. 58 * @return enum err ok, or error if failed. 59 */ 60 enum err oscore_interactions_init(struct oscore_interaction_t *interactions); 61 62 /** 63 * @brief Add new record to the interactions array, or replace the old one if it exists (URI paths field is used for comparison). 64 * @note To be used while registering to given resource. 65 * @param interactions Interactions array, MUST have exactly OSCORE_INTERACTIONS_COUNT elements. 66 * @param record Single record to be added or updated. 67 * @return enum err ok, or error if failed. 68 */ 69 enum err 70 oscore_interactions_set_record(struct oscore_interaction_t *interactions, 71 struct oscore_interaction_t *record); 72 73 /** 74 * @brief Search for the record matching given token and return a pointer to it. 75 * @note To be used while encrypting a notification on the server side, and confirming its AAD on the client side. 76 * @param interactions Interactions array, MUST have exactly OSCORE_INTERACTIONS_COUNT elements. 77 * @param token Token buffer to match. 78 * @param token_len Token buffer size. 79 * @param record [out] Pointer to the matching record. 80 * @return enum err ok, or error if failed. 81 */ 82 enum err 83 oscore_interactions_get_record(struct oscore_interaction_t *interactions, 84 uint8_t *token, uint8_t token_len, 85 struct oscore_interaction_t **record); 86 87 /** 88 * @brief Remove a record that matches given URI paths field. 89 * @note To be used while de-registering to given resource. 90 * @param interactions Interactions array, MUST have exactly OSCORE_INTERACTIONS_COUNT elements. 91 * @param token Token buffer to match. 92 * @param token_len Token buffer size. 93 * @return enum err ok, or error if failed. 94 */ 95 enum err 96 oscore_interactions_remove_record(struct oscore_interaction_t *interactions, 97 uint8_t *token, uint8_t token_len); 98 99 /** 100 * @brief Wrapper for handling OSCORE interactions to be executed before main encryption/decryption logic. 101 * 102 * @param msg_type Message type of the packet. 103 * @param token Token byte array. MUST NOT be NULL, but can be empty. 104 * @param interactions Interactions array, MUST have exactly OSCORE_INTERACTIONS_COUNT elements. 105 * @param request_piv Output request_piv (to be updated if needed). 106 * @param request_kid Output request_kid (to be updated if needed). 107 * @return enum err ok, or error if failed. 108 */ 109 enum err oscore_interactions_read_wrapper( 110 enum o_coap_msg msg_type, struct byte_array *token, 111 struct oscore_interaction_t *interactions, 112 struct byte_array *request_piv, struct byte_array *request_kid); 113 114 /** 115 * @brief Wrapper for handling OSCORE interactions to be executed after main encryption/decryption logic. 116 * 117 * @param msg_type Message type of the packet. 118 * @param token Token byte array. MUST NOT be NULL, but can be empty. 119 * @param uri_paths URI Paths byte array. MUST NOT be null, but can be empty. 120 * @param interactions Interactions array, MUST have exactly OSCORE_INTERACTIONS_COUNT elements. 121 * @param request_piv Current value of request_piv. 122 * @param request_kid Current value of request_kid. 123 * @return enum err ok, or error if failed. 124 */ 125 enum err oscore_interactions_update_wrapper( 126 enum o_coap_msg msg_type, struct byte_array *token, 127 struct byte_array *uri_paths, struct oscore_interaction_t *interactions, 128 struct byte_array *request_piv, struct byte_array *request_kid); 129 130 #endif 131
