Diff: TARGET_NRF5/source/btle/btle_security.cpp

Revision:

638:c90ae1400bf2

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TARGET_NRF5/source/btle/btle_security.cpp	Wed Sep 14 14:39:43 2016 +0100
@@ -0,0 +1,325 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "btle.h"
+
+#include "nRF5xn.h"
+
+extern "C" {
+#include "pstorage.h"
+#include "device_manager.h"
+#include "id_manager.h"
+}
+
+#include "btle_security.h"
+
+static dm_application_instance_t applicationInstance;
+static bool                      initialized = false;
+static ret_code_t dm_handler(dm_handle_t const *p_handle, dm_event_t const *p_event, ret_code_t event_result);
+
+// default security parameters. Avoid "holes" between member assigments in order to compile by gcc++11.
+static ble_gap_sec_params_t securityParameters = {
+    .bond          = true,         /**< Perform bonding. */
+    .mitm          = true,         /**< Man In The Middle protection required. */
+    .lesc          = false,        /**< Enable LE Secure Connection pairing. */
+    .keypress      = false,        /**< Enable generation of keypress notifications. */
+    .io_caps       = SecurityManager::IO_CAPS_NONE, /**< IO capabilities, see @ref BLE_GAP_IO_CAPS. */
+    .oob           = 0,            /**< Out Of Band data available. */
+    .min_key_size  = 16,           /**< Minimum encryption key size in octets between 7 and 16. If 0 then not applicable in this instance. */
+    .max_key_size  = 16,           /**< Maximum encryption key size in octets between min_key_size and 16. */
+    .kdist_own  = {
+      .enc  = 0,                   /**< Long Term Key and Master Identification. */
+      .id   = 0,                   /**< Identity Resolving Key and Identity Address Information. */
+      .sign = 0,                   /**< Connection Signature Resolving Key. */
+      .link = 0                    /**< Derive the Link Key from the LTK. */
+    },                             /**< Key distribution bitmap: keys that the local device will distribute. */
+    .kdist_peer  = {
+      .enc  = 1,                   /**< Long Term Key and Master Identification. */
+      .id   = 1,                   /**< Identity Resolving Key and Identity Address Information. */
+      .sign = 1,                   /**< Connection Signature Resolving Key. */
+      .link = 0                    /**< Derive the Link Key from the LTK. */
+    }                              /**< Key distribution bitmap: keys that the peripheral device will distribute. */
+};
+
+bool
+btle_hasInitializedSecurity(void)
+{
+    return initialized;
+}
+
+ble_error_t
+btle_initializeSecurity(bool                                      enableBonding,
+                        bool                                      requireMITM,
+                        SecurityManager::SecurityIOCapabilities_t iocaps,
+                        const SecurityManager::Passkey_t          passkey)
+{
+    /* guard against multiple initializations */
+    if (initialized) {
+        return BLE_ERROR_NONE;
+    }
+
+    if (pstorage_init() != NRF_SUCCESS) {
+        return BLE_ERROR_UNSPECIFIED;
+    }
+
+    ret_code_t rc;
+    if (passkey) {
+        ble_opt_t opts;
+        opts.gap_opt.passkey.p_passkey = const_cast<uint8_t *>(passkey);
+        if ((rc = sd_ble_opt_set(BLE_GAP_OPT_PASSKEY, &opts)) != NRF_SUCCESS) {
+            switch (rc) {
+                case BLE_ERROR_INVALID_CONN_HANDLE:
+                case NRF_ERROR_INVALID_ADDR:
+                case NRF_ERROR_INVALID_PARAM:
+                default:
+                    return BLE_ERROR_INVALID_PARAM;
+                case NRF_ERROR_INVALID_STATE:
+                    return BLE_ERROR_INVALID_STATE;
+                case NRF_ERROR_BUSY:
+                    return BLE_STACK_BUSY;
+            }
+        }
+    }
+
+    dm_init_param_t dm_init_param = {
+        .clear_persistent_data = false /* Set to true in case the module should clear all persistent data. */
+    };
+    if (dm_init(&dm_init_param) != NRF_SUCCESS) {
+        return BLE_ERROR_UNSPECIFIED;
+    }
+
+    // update default security parameters with function call parameters
+    securityParameters.bond = enableBonding;
+    securityParameters.mitm = requireMITM;
+    securityParameters.io_caps = iocaps;
+
+    const dm_application_param_t dm_param = {
+        .evt_handler  = dm_handler,
+        .service_type = DM_PROTOCOL_CNTXT_GATT_CLI_ID,
+        .sec_param    = securityParameters
+    };
+
+    if ((rc = dm_register(&applicationInstance, &dm_param)) != NRF_SUCCESS) {
+        switch (rc) {
+            case NRF_ERROR_INVALID_STATE:
+                return BLE_ERROR_INVALID_STATE;
+            case NRF_ERROR_NO_MEM:
+                return BLE_ERROR_NO_MEM;
+            default:
+                return BLE_ERROR_UNSPECIFIED;
+        }
+    }
+
+    initialized = true;
+    return BLE_ERROR_NONE;
+}
+
+ble_error_t
+btle_purgeAllBondingState(void)
+{
+    ret_code_t rc;
+    if ((rc = dm_device_delete_all(&applicationInstance)) == NRF_SUCCESS) {
+        return BLE_ERROR_NONE;
+    }
+
+    switch (rc) {
+        case NRF_ERROR_INVALID_STATE:
+            return BLE_ERROR_INVALID_STATE;
+        case NRF_ERROR_NO_MEM:
+            return BLE_ERROR_NO_MEM;
+        default:
+            return BLE_ERROR_UNSPECIFIED;
+    }
+}
+
+ble_error_t
+btle_getLinkSecurity(Gap::Handle_t connectionHandle, SecurityManager::LinkSecurityStatus_t *securityStatusP)
+{
+    ret_code_t rc;
+    dm_handle_t dmHandle = {
+        .appl_id = applicationInstance,
+    };
+    if ((rc = dm_handle_get(connectionHandle, &dmHandle)) != NRF_SUCCESS) {
+        if (rc == NRF_ERROR_NOT_FOUND) {
+            return BLE_ERROR_INVALID_PARAM;
+        } else {
+            return BLE_ERROR_UNSPECIFIED;
+        }
+    }
+
+    if ((rc = dm_security_status_req(&dmHandle, reinterpret_cast<dm_security_status_t *>(securityStatusP))) != NRF_SUCCESS) {
+        switch (rc) {
+            case NRF_ERROR_INVALID_STATE:
+                return BLE_ERROR_INVALID_STATE;
+            case NRF_ERROR_NO_MEM:
+                return BLE_ERROR_NO_MEM;
+            default:
+                return BLE_ERROR_UNSPECIFIED;
+        }
+    }
+
+    return BLE_ERROR_NONE;
+}
+
+ble_error_t
+btle_setLinkSecurity(Gap::Handle_t connectionHandle, SecurityManager::SecurityMode_t securityMode)
+{
+    // use default and updated parameters as starting point
+    // and modify structure based on security mode.
+    ble_gap_sec_params_t params = securityParameters;
+
+    switch (securityMode) {
+        case SecurityManager::SECURITY_MODE_ENCRYPTION_OPEN_LINK:
+            /**< Require no protection, open link. */
+            securityParameters.bond = false;
+            securityParameters.mitm = false;
+            break;
+
+        case SecurityManager::SECURITY_MODE_ENCRYPTION_NO_MITM:
+            /**< Require encryption, but no MITM protection. */
+            securityParameters.bond = true;
+            securityParameters.mitm = false;
+            break;
+
+        // not yet implemented security modes
+        case SecurityManager::SECURITY_MODE_NO_ACCESS:
+        case SecurityManager::SECURITY_MODE_ENCRYPTION_WITH_MITM:
+            /**< Require encryption and MITM protection. */
+        case SecurityManager::SECURITY_MODE_SIGNED_NO_MITM:
+            /**< Require signing or encryption, but no MITM protection. */
+        case SecurityManager::SECURITY_MODE_SIGNED_WITH_MITM:
+            /**< Require signing or encryption, and MITM protection. */
+        default:
+            return BLE_ERROR_NOT_IMPLEMENTED;
+    }
+
+    // update security settings for given connection
+    uint32_t result = sd_ble_gap_authenticate(connectionHandle, &params);
+
+    if (result == NRF_SUCCESS) {
+        return BLE_ERROR_NONE;
+    } else {
+        return BLE_ERROR_UNSPECIFIED;
+    }
+}
+
+ret_code_t
+dm_handler(dm_handle_t const *p_handle, dm_event_t const *p_event, ret_code_t event_result)
+{
+    nRF5xn               &ble             = nRF5xn::Instance(BLE::DEFAULT_INSTANCE);
+    nRF5xSecurityManager &securityManager = (nRF5xSecurityManager &) ble.getSecurityManager();
+
+    switch (p_event->event_id) {
+        case DM_EVT_SECURITY_SETUP: /* started */ {
+            const ble_gap_sec_params_t *peerParams = &p_event->event_param.p_gap_param->params.sec_params_request.peer_params;
+            securityManager.processSecuritySetupInitiatedEvent(p_event->event_param.p_gap_param->conn_handle,
+                                                                                   peerParams->bond,
+                                                                                   peerParams->mitm,
+                                                                                   (SecurityManager::SecurityIOCapabilities_t)peerParams->io_caps);
+            break;
+        }
+        case DM_EVT_SECURITY_SETUP_COMPLETE:
+            securityManager.
+                processSecuritySetupCompletedEvent(p_event->event_param.p_gap_param->conn_handle,
+                                                   (SecurityManager::SecurityCompletionStatus_t)(p_event->event_param.p_gap_param->params.auth_status.auth_status));
+            break;
+        case DM_EVT_LINK_SECURED: {
+            unsigned securityMode                    = p_event->event_param.p_gap_param->params.conn_sec_update.conn_sec.sec_mode.sm;
+            unsigned level                           = p_event->event_param.p_gap_param->params.conn_sec_update.conn_sec.sec_mode.lv;
+            SecurityManager::SecurityMode_t resolvedSecurityMode = SecurityManager::SECURITY_MODE_NO_ACCESS;
+            switch (securityMode) {
+                case 1:
+                    switch (level) {
+                        case 1:
+                            resolvedSecurityMode = SecurityManager::SECURITY_MODE_ENCRYPTION_OPEN_LINK;
+                            break;
+                        case 2:
+                            resolvedSecurityMode = SecurityManager::SECURITY_MODE_ENCRYPTION_NO_MITM;
+                            break;
+                        case 3:
+                            resolvedSecurityMode = SecurityManager::SECURITY_MODE_ENCRYPTION_WITH_MITM;
+                            break;
+                    }
+                    break;
+                case 2:
+                    switch (level) {
+                        case 1:
+                            resolvedSecurityMode = SecurityManager::SECURITY_MODE_SIGNED_NO_MITM;
+                            break;
+                        case 2:
+                            resolvedSecurityMode = SecurityManager::SECURITY_MODE_SIGNED_WITH_MITM;
+                            break;
+                    }
+                    break;
+            }
+
+            securityManager.processLinkSecuredEvent(p_event->event_param.p_gap_param->conn_handle, resolvedSecurityMode);
+            break;
+        }
+        case DM_EVT_DEVICE_CONTEXT_STORED:
+            securityManager.processSecurityContextStoredEvent(p_event->event_param.p_gap_param->conn_handle);
+            break;
+        default:
+            break;
+    }
+
+    return NRF_SUCCESS;
+}
+
+ble_error_t
+btle_createWhitelistFromBondTable(ble_gap_whitelist_t *p_whitelist)
+{
+    if (!btle_hasInitializedSecurity()) {
+        return BLE_ERROR_INITIALIZATION_INCOMPLETE;
+    }
+    ret_code_t err = dm_whitelist_create(&applicationInstance, p_whitelist);
+    if (err == NRF_SUCCESS) {
+        return BLE_ERROR_NONE;
+    } else if (err == NRF_ERROR_NULL) {
+        return BLE_ERROR_PARAM_OUT_OF_RANGE;
+    } else {
+        return BLE_ERROR_INVALID_STATE;
+    }
+}
+
+
+bool
+btle_matchAddressAndIrk(ble_gap_addr_t const * p_addr, ble_gap_irk_t const * p_irk)
+{
+    /*
+     * Use a helper function from the Nordic SDK to test whether the BLE
+     * address can be generated using the IRK.
+     */
+    return im_address_resolve(p_addr, p_irk);
+}
+
+void
+btle_generateResolvableAddress(const ble_gap_irk_t &irk, ble_gap_addr_t &address)
+{
+    /* Set type to resolvable */
+    address.addr_type = BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_RESOLVABLE;
+
+    /*
+     * Assign a random number to the most significant 3 bytes
+     * of the address.
+     */
+    address.addr[BLE_GAP_ADDR_LEN - 3] = 0x8E;
+    address.addr[BLE_GAP_ADDR_LEN - 2] = 0x4F;
+    address.addr[BLE_GAP_ADDR_LEN - 1] = 0x7C;
+
+    /* Calculate the hash and store it in the top half of the address */
+    ah(irk.irk, &address.addr[BLE_GAP_ADDR_LEN - 3], address.addr);
+}