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Diffstat (limited to 'thirdparty/nRF5_SDK_15.0.0_a53641a/components/ble/ble_lesc/ble_lesc.c')
| -rw-r--r-- | thirdparty/nRF5_SDK_15.0.0_a53641a/components/ble/ble_lesc/ble_lesc.c | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/thirdparty/nRF5_SDK_15.0.0_a53641a/components/ble/ble_lesc/ble_lesc.c b/thirdparty/nRF5_SDK_15.0.0_a53641a/components/ble/ble_lesc/ble_lesc.c new file mode 100644 index 0000000..a3d808d --- /dev/null +++ b/thirdparty/nRF5_SDK_15.0.0_a53641a/components/ble/ble_lesc/ble_lesc.c @@ -0,0 +1,443 @@ +/** + * Copyright (c) 2018 - 2018, Nordic Semiconductor ASA + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form, except as embedded into a Nordic + * Semiconductor ASA integrated circuit in a product or a software update for + * such product, must reproduce the above copyright notice, this list of + * conditions and the following disclaimer in the documentation and/or other + * materials provided with the distribution. + * + * 3. Neither the name of Nordic Semiconductor ASA nor the names of its + * contributors may be used to endorse or promote products derived from this + * software without specific prior written permission. + * + * 4. This software, with or without modification, must only be used with a + * Nordic Semiconductor ASA integrated circuit. + * + * 5. Any software provided in binary form under this license must not be reverse + * engineered, decompiled, modified and/or disassembled. + * + * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS + * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE + * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ +#include "sdk_common.h" +#if NRF_MODULE_ENABLED(BLE_LESC) + +#include "sdk_common.h" +#include "ble_gap.h" +#include "ble_lesc.h" +#include "nrf_crypto.h" +#include "nrf_crypto_mem.h" +#include "peer_manager.h" +#include "nrf_sdh_ble.h" +#include "ble_conn_state.h" +#define NRF_LOG_MODULE_NAME ble_lesc +#include "nrf_log.h" +NRF_LOG_MODULE_REGISTER(); + +/**@brief Structure holding a ECDH public key, connection handle and valid state */ +typedef struct +{ + nrf_crypto_ecc_public_key_t public_key; /**< Public key used in either central or peripheral link. */ + volatile uint16_t conn_handle; /**< Connection handle for connection that received the public key. */ + volatile bool is_valid; /**< Flag indicating that the public key was valid. */ +} ble_lesc_public_key_t; + +/**@brief Context to generate an ECC private/public key pair + */ +static nrf_crypto_ecc_key_pair_generate_context_t m_ecc_keygen_context; + + +/**@brief Context to do the LESC ECDH calculation. + */ +static nrf_crypto_ecdh_context_t m_ecdh_context; + + +/**@brief Private key to use for LESC ECDH calculations + */ +static nrf_crypto_ecc_private_key_t m_local_private_key; + + +/**@brief Public key to use for LESC ECDH calculation + */ +static ble_lesc_public_key_t m_local_public_key; + + +/**@brief Structure holding peer central LESC ECC public key and valid state + */ +static ble_lesc_public_key_t m_peer_public_key_central = +{ + .conn_handle = BLE_CONN_HANDLE_INVALID, + .is_valid = false +}; + + +/**@brief Structure holding peer peripheral LESC ECC public key and valid state + */ +static ble_lesc_public_key_t m_peer_public_key_peripheral = +{ + .conn_handle = BLE_CONN_HANDLE_INVALID, + .is_valid = false +}; + +/**@brief LESC ECC public key in a format usable by SoftDevice APIs. + * + * @note The BLE specification requires this key to be in little-endian format. + */ +static ble_gap_lesc_p256_pk_t m_lesc_public_key; + + +/**@brief LESC ECDH key in a format usable by SoftDevice APIs. + * + * @note The BLE specification requires this key to be in little-endian format. + */ +static ble_gap_lesc_dhkey_t m_lesc_ecdh_key; + + +static bool m_ble_lesc_invalid_state = false; +static bool m_keypair_generated = false; /**< Flag indicating that the local ECDH key pair was generated. */ + + +static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context); +NRF_SDH_BLE_OBSERVER(m_ble_evt_observer, BLE_LESC_OBSERVER_PRIO, ble_evt_handler, NULL); + + +/**@brief Function to calculate LESC ECDH and set it using SoftDevice API + * + * @details This function calculates a LESC ECDH key (also know as a shared secret) + * sets it using a call to @ref sd_ble_gap_lesc_dhkey_reply. + * + * @note This function will only work if there is a generated local ECC key pair (private and + * public key pair) and a valid ECC public key received from the peer on either a peripheral + * or central link. If the ECC public key from the peer is invalid, a random shared secret + * is generated and set using the @ref sd_ble_gap_lesc_dhkey_reply call. + * + * @warning This function must be run in a low interrupt priority, like the main + * application context. Running this in a high priority interrupt level + * may disrupt time critical operations like radio communications. + * + * @retval + */ +static ret_code_t ble_lesc_dhkey_calculate_and_set(ble_lesc_public_key_t * const p_peer_public_key) +{ + ret_code_t err_code = NRF_ERROR_INVALID_STATE; + size_t shared_secret_size = BLE_GAP_LESC_DHKEY_LEN; + + uint8_t * p_shared_secret = m_lesc_ecdh_key.key; + + // Check if there is a valid generated and set local ECDH public key + if (!m_keypair_generated) + { + return NRF_ERROR_INVALID_STATE; + } + + // Check if the public_key is valid + if (p_peer_public_key->is_valid) + { + err_code = nrf_crypto_ecdh_compute(&m_ecdh_context, + &m_local_private_key, + &p_peer_public_key->public_key, + p_shared_secret, + &shared_secret_size); + } + + if(err_code == NRF_SUCCESS) + { + err_code = nrf_crypto_ecc_byte_order_invert(&g_nrf_crypto_ecc_secp256r1_curve_info, + p_shared_secret, + p_shared_secret, + BLE_GAP_LESC_DHKEY_LEN); + VERIFY_SUCCESS(err_code); + } + else + { + NRF_LOG_WARNING("Creating invalid shared secret to make LESC fail."); + err_code = nrf_crypto_rng_vector_generate(p_shared_secret, BLE_GAP_LESC_DHKEY_LEN); + VERIFY_SUCCESS(err_code); + } + + NRF_LOG_DEBUG("Calling sd_ble_gap_lesc_dhkey_reply on conn_handle: %d", p_peer_public_key->conn_handle); + err_code = sd_ble_gap_lesc_dhkey_reply(p_peer_public_key->conn_handle, &m_lesc_ecdh_key); + + return err_code; +} + + +/**@brief Function to set the peer ECC public key for a peripheral link + * + * @details This call should be made to + * + * @param[in] conn_handle The connection handle to the peripheral connection. + * @param[in] p_public_key Pointer to structure holding the public key received from the peer. + * + * @retval + */ +static ret_code_t ble_lesc_peer_peripheral_public_key_set( + uint16_t conn_handle, + ble_gap_lesc_p256_pk_t const * const p_public_key) +{ + ret_code_t err_code; + + uint8_t public_raw[BLE_GAP_LESC_P256_PK_LEN]; + size_t public_raw_len = BLE_GAP_LESC_P256_PK_LEN; + + VERIFY_TRUE(conn_handle != BLE_CONN_HANDLE_INVALID, NRF_ERROR_INVALID_PARAM); + VERIFY_PARAM_NOT_NULL(p_public_key); + + memcpy(public_raw, p_public_key->pk, BLE_GAP_LESC_P256_PK_LEN); + + err_code = nrf_crypto_ecc_byte_order_invert(&g_nrf_crypto_ecc_secp256r1_curve_info, + public_raw, + public_raw, + NRF_CRYPTO_ECC_SECP256R1_RAW_PUBLIC_KEY_SIZE); + VERIFY_SUCCESS(err_code); + + + err_code = nrf_crypto_ecc_public_key_from_raw(&g_nrf_crypto_ecc_secp256r1_curve_info, + &m_peer_public_key_peripheral.public_key, + public_raw, + public_raw_len); + + if (err_code == NRF_SUCCESS) + { + m_peer_public_key_peripheral.is_valid = true; + } + else + { + m_peer_public_key_peripheral.is_valid = false; + } + + m_peer_public_key_peripheral.conn_handle = conn_handle; + + return NRF_SUCCESS; +} + +/**@brief Function to set peer ECC public key for a central link + * + * @details Setting the peer ECC public key will start a + * + * @param[in] conn_handle The connection handle to the peripheral connection. + * @param[in] p_public_key Pointer to structure holding the public key received from the peer. + * + * @retval + */ +static ret_code_t ble_lesc_peer_central_public_key_set( + uint16_t conn_handle, + ble_gap_lesc_p256_pk_t const * const p_public_key) +{ + ret_code_t err_code; + + uint8_t public_raw[BLE_GAP_LESC_P256_PK_LEN]; + size_t public_raw_len = BLE_GAP_LESC_P256_PK_LEN; + + VERIFY_TRUE(conn_handle != BLE_CONN_HANDLE_INVALID, NRF_ERROR_INVALID_PARAM); + VERIFY_PARAM_NOT_NULL(p_public_key); + + memcpy(public_raw, p_public_key->pk, BLE_GAP_LESC_P256_PK_LEN); + + err_code = nrf_crypto_ecc_byte_order_invert(&g_nrf_crypto_ecc_secp256r1_curve_info, + public_raw, + public_raw, + NRF_CRYPTO_ECC_SECP256R1_RAW_PUBLIC_KEY_SIZE); + VERIFY_SUCCESS(err_code); + + err_code = nrf_crypto_ecc_public_key_from_raw(&g_nrf_crypto_ecc_secp256r1_curve_info, + &m_peer_public_key_central.public_key, + public_raw, + public_raw_len); + + if (err_code == NRF_SUCCESS) + { + m_peer_public_key_central.is_valid = true; + } + else + { + m_peer_public_key_central.is_valid = false; + } + + m_peer_public_key_central.conn_handle = conn_handle; + + return NRF_SUCCESS; +} + + +/**@brief BLE event handler for LESC DHKEY requests + */ +static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context) +{ + ret_code_t err_code = NRF_SUCCESS; + uint16_t conn_handle = p_ble_evt->evt.gap_evt.conn_handle; + uint16_t role = ble_conn_state_role(conn_handle); + + switch (p_ble_evt->header.evt_id) + { + case BLE_GAP_EVT_LESC_DHKEY_REQUEST: + { + NRF_LOG_DEBUG("Handling BLE_GAP_EVT_LESC_DHKEY_REQUEST"); + + ble_gap_lesc_p256_pk_t const * p_pk_peer = + p_ble_evt->evt.gap_evt.params.lesc_dhkey_request.p_pk_peer; + + if (role == BLE_GAP_ROLE_CENTRAL) + { + err_code = ble_lesc_peer_central_public_key_set(conn_handle, + p_pk_peer); + } + else if (role == BLE_GAP_ROLE_PERIPH) + { + err_code = ble_lesc_peer_peripheral_public_key_set(conn_handle, + p_pk_peer); + } + + if (err_code != NRF_SUCCESS) + { + // Set the state to invalid + m_ble_lesc_invalid_state = true; + } + + break; + } + + default: + break; + } +} + + +ret_code_t ble_lesc_init(void) +{ + ret_code_t err_code; + +#if NRF_CRYPTO_ALLOCATOR == NRF_CRYPTO_ALLOCATOR_NRF_MALLOC + + // Initialize mem_manager if used by nrf_crypto + err_code = nrf_mem_init(); + VERIFY_SUCCESS(err_code); + +#endif + + // Ensure that nrf_crypto has been initialized + err_code = nrf_crypto_init(); + VERIFY_SUCCESS(err_code); + +#if defined(NRF_CRYPTO_RNG_AUTO_INIT_ENABLED) && (NRF_CRYPTO_RNG_AUTO_INIT_ENABLED == 1) + + // Do nothing. RNG is initialized with nrf_crypto_init call. + +#elif defined((NRF_CRYPTO_RNG_AUTO_INIT_ENABLED) && (NRF_CRYPTO_RNG_AUTO_INIT_ENABLED == 0) + + // Initialize the RNG + err_code = nrf_crypto_rng_init(NULL, NULL); + VERIFY_SUCCESS(err_code); + +#else + + #error Invalid sdk_config.h (does not contain NRF_CRYPTO_RNG_AUTO_INIT_ENABLED) + +#endif // defined(NRF_CRYPTO_RNG_AUTO_INIT_ENABLED) && (NRF_CRYPTO_RNG_AUTO_INIT_ENABLED == 1) + + return err_code; +} + + +ret_code_t ble_lesc_ecc_keypair_generate_and_set(void) +{ + ret_code_t err_code; + + size_t public_len = BLE_GAP_LESC_P256_PK_LEN; + + // Update flag to indicate that there is no valid private key + m_keypair_generated = false; + + err_code = nrf_crypto_ecc_key_pair_generate(&m_ecc_keygen_context, + &g_nrf_crypto_ecc_secp256r1_curve_info, + &m_local_private_key, + &m_local_public_key.public_key); + VERIFY_SUCCESS(err_code); + + // Converting public key to raw format. + err_code = nrf_crypto_ecc_public_key_to_raw(&m_local_public_key.public_key, + (uint8_t *)m_lesc_public_key.pk, + &public_len); + VERIFY_SUCCESS(err_code); + + // Convert the raw public key to little-endian (required for BLE) + err_code = nrf_crypto_ecc_byte_order_invert(&g_nrf_crypto_ecc_secp256r1_curve_info, + m_lesc_public_key.pk, + m_lesc_public_key.pk, + NRF_CRYPTO_ECC_SECP256R1_RAW_PUBLIC_KEY_SIZE); + VERIFY_SUCCESS(err_code); + + // Set the local public key used for all LESC pairing procedures. + err_code = pm_lesc_public_key_set(&m_lesc_public_key); + + if(err_code == NRF_SUCCESS) + { + // Set the flag to indicate that there is a valid ECDH key pair generated + m_keypair_generated = true; + } + + return err_code; +} + + +ret_code_t ble_lesc_ecc_local_public_key_get(ble_gap_lesc_p256_pk_t const ** pp_lesc_public_key) +{ + VERIFY_PARAM_NOT_NULL(pp_lesc_public_key); + VERIFY_TRUE(m_keypair_generated, NRF_ERROR_INVALID_STATE); + + (*pp_lesc_public_key) = &m_lesc_public_key; + return NRF_SUCCESS; +} + + +ret_code_t ble_lesc_service_request_handler(void) +{ + ret_code_t err_code = NRF_SUCCESS; + + // If the LESC module is in an invalid state restart is required + if (m_ble_lesc_invalid_state) + { + return NRF_ERROR_INVALID_STATE; + } + + if (m_peer_public_key_central.conn_handle != BLE_CONN_HANDLE_INVALID) + { + // The central link has received a DHKEY_REQUEST. + err_code = ble_lesc_dhkey_calculate_and_set(&m_peer_public_key_central); + + m_peer_public_key_central.conn_handle = BLE_CONN_HANDLE_INVALID; + } + else if (m_peer_public_key_peripheral.conn_handle != BLE_CONN_HANDLE_INVALID) + { + // The peripheral link has received a DHKEY_REQUEST. + err_code = ble_lesc_dhkey_calculate_and_set(&m_peer_public_key_peripheral); + + m_peer_public_key_peripheral.conn_handle = BLE_CONN_HANDLE_INVALID; + } + else + { + // Do nothing + } + + return err_code; +} + +#endif // NRF_MODULE_ENABLED(BLE_LESC) |