btle_security.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #include "btle.h"
00018 #include "pstorage.h "
00019 
00020 #include "nRF5xGap.h"
00021 #include "nRF5xSecurityManager.h"
00022 
00023 #include "device_manager.h "
00024 #include "btle_security.h"
00025 
00026 static dm_application_instance_t applicationInstance;
00027 static ret_code_t dm_handler(dm_handle_t const *p_handle, dm_event_t const *p_event, ret_code_t event_result);
00028 
00029 ble_error_t
00030 btle_initializeSecurity(bool                                      enableBonding,
00031                         bool                                      requireMITM,
00032                         SecurityManager::SecurityIOCapabilities_t iocaps,
00033                         const SecurityManager::Passkey_t          passkey)
00034 {
00035     /* guard against multiple initializations */
00036     static bool initialized = false;
00037     if (initialized) {
00038         return BLE_ERROR_NONE;
00039     }
00040 
00041     if (pstorage_init() != NRF_SUCCESS) {
00042         return BLE_ERROR_UNSPECIFIED;
00043     }
00044 
00045     ret_code_t rc;
00046     if (passkey) {
00047         ble_opt_t opts;
00048         opts.gap_opt.passkey.p_passkey = const_cast<uint8_t *>(passkey);
00049         if ((rc = sd_ble_opt_set(BLE_GAP_OPT_PASSKEY, &opts)) != NRF_SUCCESS) {
00050             switch (rc) {
00051                 case BLE_ERROR_INVALID_CONN_HANDLE:
00052                 case NRF_ERROR_INVALID_ADDR:
00053                 case NRF_ERROR_INVALID_PARAM:
00054                 default:
00055                     return BLE_ERROR_INVALID_PARAM;
00056                 case NRF_ERROR_INVALID_STATE:
00057                     return BLE_ERROR_INVALID_STATE;
00058                 case NRF_ERROR_BUSY:
00059                     return BLE_STACK_BUSY;
00060             }
00061         }
00062     }
00063 
00064     dm_init_param_t dm_init_param = {
00065         .clear_persistent_data = false /* Set to true in case the module should clear all persistent data. */
00066     };
00067     if (dm_init(&dm_init_param) != NRF_SUCCESS) {
00068         return BLE_ERROR_UNSPECIFIED;
00069     }
00070 
00071     const dm_application_param_t dm_param = {
00072         .evt_handler  = dm_handler,
00073         .service_type = DM_PROTOCOL_CNTXT_GATT_CLI_ID,
00074         .sec_param    = {
00075             .bond          = enableBonding,/**< Perform bonding. */
00076             .mitm          = requireMITM,  /**< Man In The Middle protection required. */
00077             .io_caps       = iocaps,       /**< IO capabilities, see @ref BLE_GAP_IO_CAPS. */
00078             .oob           = 0,            /**< Out Of Band data available. */
00079             .min_key_size  = 16,           /**< Minimum encryption key size in octets between 7 and 16. If 0 then not applicable in this instance. */
00080             .max_key_size  = 16,           /**< Maximum encryption key size in octets between min_key_size and 16. */
00081             .kdist_periph  = {
00082               .enc  = 1,                     /**< Long Term Key and Master Identification. */
00083               .id   = 1,                     /**< Identity Resolving Key and Identity Address Information. */
00084               .sign = 1,                     /**< Connection Signature Resolving Key. */
00085             },                             /**< Key distribution bitmap: keys that the peripheral device will distribute. */
00086         }
00087     };
00088 
00089     if ((rc = dm_register(&applicationInstance, &dm_param)) != NRF_SUCCESS) {
00090         switch (rc) {
00091             case NRF_ERROR_INVALID_STATE:
00092                 return BLE_ERROR_INVALID_STATE;
00093             case NRF_ERROR_NO_MEM:
00094                 return BLE_ERROR_NO_MEM;
00095             default:
00096                 return BLE_ERROR_UNSPECIFIED;
00097         }
00098     }
00099 
00100     initialized = true;
00101     return BLE_ERROR_NONE;
00102 }
00103 
00104 ble_error_t
00105 btle_purgeAllBondingState(void)
00106 {
00107     ret_code_t rc;
00108     if ((rc = dm_device_delete_all(&applicationInstance)) == NRF_SUCCESS) {
00109         return BLE_ERROR_NONE;
00110     }
00111 
00112     switch (rc) {
00113         case NRF_ERROR_INVALID_STATE:
00114             return BLE_ERROR_INVALID_STATE;
00115         case NRF_ERROR_NO_MEM:
00116             return BLE_ERROR_NO_MEM;
00117         default:
00118             return BLE_ERROR_UNSPECIFIED;
00119     }
00120 }
00121 
00122 ble_error_t
00123 btle_getLinkSecurity(Gap::Handle_t connectionHandle, SecurityManager::LinkSecurityStatus_t *securityStatusP)
00124 {
00125     ret_code_t rc;
00126     dm_handle_t dmHandle = {
00127         .appl_id = applicationInstance,
00128     };
00129     if ((rc = dm_handle_get(connectionHandle, &dmHandle)) != NRF_SUCCESS) {
00130         if (rc == NRF_ERROR_NOT_FOUND) {
00131             return BLE_ERROR_INVALID_PARAM;
00132         } else {
00133             return BLE_ERROR_UNSPECIFIED;
00134         }
00135     }
00136 
00137     if ((rc = dm_security_status_req(&dmHandle, reinterpret_cast<dm_security_status_t *>(securityStatusP))) != NRF_SUCCESS) {
00138         switch (rc) {
00139             case NRF_ERROR_INVALID_STATE:
00140                 return BLE_ERROR_INVALID_STATE;
00141             case NRF_ERROR_NO_MEM:
00142                 return BLE_ERROR_NO_MEM;
00143             default:
00144                 return BLE_ERROR_UNSPECIFIED;
00145         }
00146     }
00147 
00148     return BLE_ERROR_NONE;
00149 }
00150 
00151 ret_code_t
00152 dm_handler(dm_handle_t const *p_handle, dm_event_t const *p_event, ret_code_t event_result)
00153 {
00154     switch (p_event->event_id) {
00155         case DM_EVT_SECURITY_SETUP: /* started */ {
00156             const ble_gap_sec_params_t *peerParams = &p_event->event_param.p_gap_param->params.sec_params_request.peer_params;
00157             nRF5xSecurityManager::getInstance().processSecuritySetupInitiatedEvent(p_event->event_param.p_gap_param->conn_handle,
00158                                                                                    peerParams->bond,
00159                                                                                    peerParams->mitm,
00160                                                                                    (SecurityManager::SecurityIOCapabilities_t)peerParams->io_caps);
00161             break;
00162         }
00163         case DM_EVT_SECURITY_SETUP_COMPLETE:
00164             nRF5xSecurityManager::getInstance().
00165                 processSecuritySetupCompletedEvent(p_event->event_param.p_gap_param->conn_handle,
00166                                                    (SecurityManager::SecurityCompletionStatus_t)(p_event->event_param.p_gap_param->params.auth_status.auth_status));
00167             break;
00168         case DM_EVT_LINK_SECURED: {
00169             unsigned securityMode                    = p_event->event_param.p_gap_param->params.conn_sec_update.conn_sec.sec_mode.sm;
00170             unsigned level                           = p_event->event_param.p_gap_param->params.conn_sec_update.conn_sec.sec_mode.lv;
00171             SecurityManager::SecurityMode_t resolvedSecurityMode = SecurityManager::SECURITY_MODE_NO_ACCESS;
00172             switch (securityMode) {
00173                 case 1:
00174                     switch (level) {
00175                         case 1:
00176                             resolvedSecurityMode = SecurityManager::SECURITY_MODE_ENCRYPTION_OPEN_LINK;
00177                             break;
00178                         case 2:
00179                             resolvedSecurityMode = SecurityManager::SECURITY_MODE_ENCRYPTION_NO_MITM;
00180                             break;
00181                         case 3:
00182                             resolvedSecurityMode = SecurityManager::SECURITY_MODE_ENCRYPTION_WITH_MITM;
00183                             break;
00184                     }
00185                     break;
00186                 case 2:
00187                     switch (level) {
00188                         case 1:
00189                             resolvedSecurityMode = SecurityManager::SECURITY_MODE_SIGNED_NO_MITM;
00190                             break;
00191                         case 2:
00192                             resolvedSecurityMode = SecurityManager::SECURITY_MODE_SIGNED_WITH_MITM;
00193                             break;
00194                     }
00195                     break;
00196             }
00197 
00198             nRF5xSecurityManager::getInstance().processLinkSecuredEvent(p_event->event_param.p_gap_param->conn_handle, resolvedSecurityMode);
00199             break;
00200         }
00201         case DM_EVT_DEVICE_CONTEXT_STORED:
00202             nRF5xSecurityManager::getInstance().processSecurityContextStoredEvent(p_event->event_param.p_gap_param->conn_handle);
00203             break;
00204         default:
00205             break;
00206     }
00207 
00208     return NRF_SUCCESS;
00209 }