GapAdvertisingData.h

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 #ifndef __GAP_ADVERTISING_DATA_H__
00018 #define __GAP_ADVERTISING_DATA_H__
00019 
00020 #include <stdint.h>
00021 #include <string.h>
00022 
00023 #include "blecommon.h"
00024 
00025 #define GAP_ADVERTISING_DATA_MAX_PAYLOAD        (31)
00026 
00027 /**************************************************************************/
00028 /*!
00029     \brief
00030     This class provides several helper functions to generate properly
00031     formatted GAP Advertising and Scan Response data payloads.
00032 
00033     \note
00034     See Bluetooth Specification 4.0 (Vol. 3), Part C, Sections 11 and 18
00035     for further information on Advertising and Scan Response data.
00036 
00037     \par Advertising and Scan Response Payloads
00038     Advertising data and Scan Response data are organized around a set of
00039     data types called 'AD types' in Bluetooth 4.0 (see the Bluetooth Core
00040     Specification v4.0, Vol. 3, Part C, Sections 11 and 18).
00041 
00042     \par
00043     Each AD type has its own standardized assigned number, as defined
00044     by the Bluetooth SIG:
00045     https://www.bluetooth.org/en-us/specification/assigned-numbers/generic-access-profile
00046 
00047     \par
00048     For convenience, all appropriate AD types are encapsulated
00049     in GapAdvertisingData::DataType.
00050 
00051     \par
00052     Before the AD Types and their payload (if any) can be inserted into
00053     the Advertising or Scan Response frames, they need to be formatted as
00054     follows:
00055 
00056     \li \c Record length (1 byte).
00057     \li \c AD Type (1 byte).
00058     \li \c AD payload (optional; only present if record length > 1).
00059 
00060     \par
00061     This class takes care of properly formatting the payload, performs
00062     some basic checks on the payload length, and tries to avoid common
00063     errors like adding an exclusive AD field twice in the Advertising
00064     or Scan Response payload.
00065 
00066     \par EXAMPLE
00067 
00068     \code
00069 
00070     // ToDo
00071 
00072     \endcode
00073 */
00074 /**************************************************************************/
00075 class GapAdvertisingData
00076 {
00077 public:
00078     /**********************************************************************/
00079     /*!
00080         \brief
00081         A list of Advertising Data types commonly used by peripherals.
00082         These AD types are used to describe the capabilities of the
00083         peripheral, and are inserted inside the advertising or scan
00084         response payloads.
00085 
00086         \par Source
00087         \li \c Bluetooth Core Specification 4.0 (Vol. 3), Part C, Section 11, 18
00088         \li \c https://www.bluetooth.org/en-us/specification/assigned-numbers/generic-access-profile
00089     */
00090     /**********************************************************************/
00091     enum DataType_t {
00092         FLAGS                              = 0x01, /**< \ref *Flags */
00093         INCOMPLETE_LIST_16BIT_SERVICE_IDS  = 0x02, /**< Incomplete list of 16-bit Service IDs */
00094         COMPLETE_LIST_16BIT_SERVICE_IDS    = 0x03, /**< Complete list of 16-bit Service IDs */
00095         INCOMPLETE_LIST_32BIT_SERVICE_IDS  = 0x04, /**< Incomplete list of 32-bit Service IDs (not relevant for Bluetooth 4.0) */
00096         COMPLETE_LIST_32BIT_SERVICE_IDS    = 0x05, /**< Complete list of 32-bit Service IDs (not relevant for Bluetooth 4.0) */
00097         INCOMPLETE_LIST_128BIT_SERVICE_IDS = 0x06, /**< Incomplete list of 128-bit Service IDs */
00098         COMPLETE_LIST_128BIT_SERVICE_IDS   = 0x07, /**< Complete list of 128-bit Service IDs */
00099         SHORTENED_LOCAL_NAME               = 0x08, /**< Shortened Local Name */
00100         COMPLETE_LOCAL_NAME                = 0x09, /**< Complete Local Name */
00101         TX_POWER_LEVEL                     = 0x0A, /**< TX Power Level (in dBm) */
00102         DEVICE_ID                          = 0x10, /**< Device ID */
00103         SLAVE_CONNECTION_INTERVAL_RANGE    = 0x12, /**< Slave Connection Interval Range */
00104         LIST_128BIT_SOLICITATION_IDS       = 0x15, /**< List of 128 bit service UUIDs the device is looking for */
00105         SERVICE_DATA                       = 0x16, /**< Service Data */
00106         APPEARANCE                         = 0x19, /**< \ref Appearance */
00107         ADVERTISING_INTERVAL               = 0x1A, /**< Advertising Interval */
00108         MANUFACTURER_SPECIFIC_DATA         = 0xFF  /**< Manufacturer Specific Data */
00109     };
00110     typedef enum DataType_t DataType; /* Deprecated type alias. This may be dropped in a future release. */
00111 
00112     /**********************************************************************/
00113     /*!
00114         \brief
00115         A list of values for the FLAGS AD Type.
00116 
00117         \note
00118         You can use more than one value in the FLAGS AD Type (ex.
00119         LE_GENERAL_DISCOVERABLE and BREDR_NOT_SUPPORTED).
00120 
00121         \par Source
00122         \li \c Bluetooth Core Specification 4.0 (Vol. 3), Part C, Section 18.1
00123     */
00124     /**********************************************************************/
00125     enum Flags_t {
00126         LE_LIMITED_DISCOVERABLE = 0x01, /**< *Peripheral device is discoverable for a limited period of time. */
00127         LE_GENERAL_DISCOVERABLE = 0x02, /**< Peripheral device is discoverable at any moment. */
00128         BREDR_NOT_SUPPORTED     = 0x04, /**< Peripheral device is LE only. */
00129         SIMULTANEOUS_LE_BREDR_C = 0x08, /**< Not relevant - central mode only. */
00130         SIMULTANEOUS_LE_BREDR_H = 0x10  /**< Not relevant - central mode only. */
00131     };
00132     typedef enum Flags_t Flags; /* Deprecated type alias. This may be dropped in a future release. */
00133 
00134     /**********************************************************************/
00135     /*!
00136         \brief
00137         A list of values for the APPEARANCE AD Type, which describes the
00138         physical shape or appearance of the device.
00139 
00140         \par Source
00141         \li \c Bluetooth Core Specification Supplement, Part A, Section 1.12
00142         \li \c Bluetooth Core Specification 4.0 (Vol. 3), Part C, Section 12.2
00143         \li \c https://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.gap.appearance.xml
00144     */
00145     /**********************************************************************/
00146     enum Appearance_t {
00147         UNKNOWN                                        = 0,     /**< Unknown or unspecified appearance type. */
00148         GENERIC_PHONE                                  = 64,    /**< Generic Phone. */
00149         GENERIC_COMPUTER                               = 128,   /**< Generic Computer. */
00150         GENERIC_WATCH                                  = 192,   /**< Generic Watch. */
00151         WATCH_SPORTS_WATCH                             = 193,   /**< Sports Watch. */
00152         GENERIC_CLOCK                                  = 256,   /**< Generic Clock. */
00153         GENERIC_DISPLAY                                = 320,   /**< Generic Display. */
00154         GENERIC_REMOTE_CONTROL                         = 384,   /**< Generic Remote Control. */
00155         GENERIC_EYE_GLASSES                            = 448,   /**< Generic Eye Glasses. */
00156         GENERIC_TAG                                    = 512,   /**< Generic Tag. */
00157         GENERIC_KEYRING                                = 576,   /**< Generic Keyring. */
00158         GENERIC_MEDIA_PLAYER                           = 640,   /**< Generic Media Player. */
00159         GENERIC_BARCODE_SCANNER                        = 704,   /**< Generic Barcode Scanner. */
00160         GENERIC_THERMOMETER                            = 768,   /**< Generic Thermometer. */
00161         THERMOMETER_EAR                                = 769,   /**< Ear Thermometer. */
00162         GENERIC_HEART_RATE_SENSOR                      = 832,   /**< Generic Heart Rate Sensor. */
00163         HEART_RATE_SENSOR_HEART_RATE_BELT              = 833,   /**< Belt Heart Rate Sensor. */
00164         GENERIC_BLOOD_PRESSURE                         = 896,   /**< Generic Blood Pressure. */
00165         BLOOD_PRESSURE_ARM                             = 897,   /**< Arm Blood Pressure. */
00166         BLOOD_PRESSURE_WRIST                           = 898,   /**< Wrist Blood Pressure. */
00167         HUMAN_INTERFACE_DEVICE_HID                     = 960,   /**< Human Interface Device (HID). */
00168         KEYBOARD                                       = 961,   /**< Keyboard. */
00169         MOUSE                                          = 962,   /**< Mouse. */
00170         JOYSTICK                                       = 963,   /**< Joystick. */
00171         GAMEPAD                                        = 964,   /**< Gamepad. */
00172         DIGITIZER_TABLET                               = 965,   /**< Digitizer Tablet. */
00173         CARD_READER                                    = 966,   /**< Card Reader. */
00174         DIGITAL_PEN                                    = 967,   /**< Digital Pen. */
00175         BARCODE_SCANNER                                = 968,   /**< Barcode Scanner. */
00176         GENERIC_GLUCOSE_METER                          = 1024,  /**< Generic Glucose Meter. */
00177         GENERIC_RUNNING_WALKING_SENSOR                 = 1088,  /**< Generic Running/Walking Sensor. */
00178         RUNNING_WALKING_SENSOR_IN_SHOE                 = 1089,  /**< In Shoe Running/Walking Sensor. */
00179         RUNNING_WALKING_SENSOR_ON_SHOE                 = 1090,  /**< On Shoe Running/Walking Sensor. */
00180         RUNNING_WALKING_SENSOR_ON_HIP                  = 1091,  /**< On Hip Running/Walking Sensor. */
00181         GENERIC_CYCLING                                = 1152,  /**< Generic Cycling. */
00182         CYCLING_CYCLING_COMPUTER                       = 1153,  /**< Cycling Computer. */
00183         CYCLING_SPEED_SENSOR                           = 1154,  /**< Cycling Speed Sensor. */
00184         CYCLING_CADENCE_SENSOR                         = 1155,  /**< Cycling Cadence Sensor. */
00185         CYCLING_POWER_SENSOR                           = 1156,  /**< Cycling Power Sensor. */
00186         CYCLING_SPEED_AND_CADENCE_SENSOR               = 1157,  /**< Cycling Speed and Cadence Sensor. */
00187         PULSE_OXIMETER_GENERIC                         = 3136,  /**< Generic Pulse Oximeter. */
00188         PULSE_OXIMETER_FINGERTIP                       = 3137,  /**< Fingertip Pulse Oximeter. */
00189         PULSE_OXIMETER_WRIST_WORN                      = 3138,  /**< Wrist Worn Pulse Oximeter. */
00190         GENERIC_WEIGHT_SCALE                           = 3200,  /**< Generic Weight Scale. */
00191         OUTDOOR_GENERIC                                = 5184,  /**< Generic Outdoor. */
00192         OUTDOOR_LOCATION_DISPLAY_DEVICE                = 5185,  /**< Outdoor Location Display Device. */
00193         OUTDOOR_LOCATION_AND_NAVIGATION_DISPLAY_DEVICE = 5186,  /**< Outdoor Location and Navigation Display Device. */
00194         OUTDOOR_LOCATION_POD                           = 5187,  /**< Outdoor Location Pod. */
00195         OUTDOOR_LOCATION_AND_NAVIGATION_POD            = 5188   /**< Outdoor Location and Navigation Pod. */
00196     };
00197     typedef enum Appearance_t Appearance; /* Deprecated type alias. This may be dropped in a future release. */
00198 
00199     GapAdvertisingData(void) : _payload(), _payloadLen(0), _appearance(GENERIC_TAG) {
00200         /* empty */
00201     }
00202 
00203     /**
00204      * Adds advertising data based on the specified AD type (see DataType).
00205      * If the supplied AD type is already present in the advertising
00206      * payload, then the value is updated.
00207      *
00208      * @param[in] advDataType  The Advertising 'DataType' to add.
00209      * @param[in] payload      Pointer to the payload contents.
00210      * @param[in] len          Size of the payload in bytes.
00211      *
00212      * @return BLE_ERROR_BUFFER_OVERFLOW if the new value causes the
00213      *         advertising buffer to overflow. BLE_ERROR_NONE is returned
00214      *         on success.
00215      *
00216      * @note When the specified AD type is INCOMPLETE_LIST_16BIT_SERVICE_IDS,
00217      *       COMPLETE_LIST_16BIT_SERVICE_IDS, INCOMPLETE_LIST_32BIT_SERVICE_IDS,
00218      *       COMPLETE_LIST_32BIT_SERVICE_IDS, INCOMPLETE_LIST_128BIT_SERVICE_IDS,
00219      *       COMPLETE_LIST_128BIT_SERVICE_IDS or LIST_128BIT_SOLICITATION_IDS the
00220      *       supplied value is appended to the values previously added to the
00221      *       payload.
00222      */
00223     ble_error_t addData(DataType_t advDataType, const uint8_t *payload, uint8_t len)
00224     {
00225         // find field
00226         uint8_t* field = findField(advDataType);
00227 
00228         if (field) {
00229             // Field type already exist, either add to field or replace
00230             return addField(advDataType, payload, len, field);
00231         } else {
00232             // field doesn't exists, insert new
00233             return appendField(advDataType, payload, len);
00234         }
00235     }
00236 
00237     /**
00238      * Update a particular ADV field in the advertising payload (based on
00239      * matching type).
00240      *
00241      * @param[in] advDataType  The Advertising 'DataType' to add.
00242      * @param[in] payload      Pointer to the payload contents.
00243      * @param[in] len          Size of the payload in bytes.
00244      *
00245      * @return BLE_ERROR_UNSPECIFIED if the specified field is not found,
00246      *         BLE_ERROR_BUFFER_OVERFLOW if the new value causes the
00247      *         advertising buffer to overflow. BLE_ERROR_NONE is returned
00248      *         on success.
00249      */
00250     ble_error_t updateData(DataType_t advDataType, const uint8_t *payload, uint8_t len)
00251     {
00252         // find field
00253         uint8_t* field = findField(advDataType);
00254 
00255         if (field) {
00256             // Field type already exist, replace field contents
00257             return updateField(advDataType, payload, len, field);
00258         } else {
00259             // field doesn't exists, return an error
00260             return BLE_ERROR_UNSPECIFIED;
00261         }
00262     }
00263 
00264     /**
00265      * Helper function to add APPEARANCE data to the advertising payload.
00266      *
00267      * @param  appearance
00268      *           The APPEARANCE value to add.
00269      *
00270      * @return BLE_ERROR_BUFFER_OVERFLOW if the specified data would cause the
00271      * advertising buffer to overflow, else BLE_ERROR_NONE.
00272      */
00273     ble_error_t addAppearance(Appearance appearance = GENERIC_TAG) {
00274         _appearance = appearance;
00275         return addData(GapAdvertisingData::APPEARANCE, (uint8_t *)&appearance, 2);
00276     }
00277 
00278     /**
00279      * Helper function to add FLAGS data to the advertising payload.
00280      * @param  flags
00281      *           LE_LIMITED_DISCOVERABLE
00282      *             The peripheral is discoverable for a limited period of time.
00283      *           LE_GENERAL_DISCOVERABLE
00284      *             The peripheral is permanently discoverable.
00285      *           BREDR_NOT_SUPPORTED
00286      *             This peripheral is a Bluetooth Low Energy only device (no EDR support).
00287      *
00288      * @return BLE_ERROR_BUFFER_OVERFLOW if the specified data would cause the
00289      * advertising buffer to overflow, else BLE_ERROR_NONE.
00290      */
00291     ble_error_t addFlags(uint8_t flags = LE_GENERAL_DISCOVERABLE) {
00292         return addData(GapAdvertisingData::FLAGS, &flags, 1);
00293     }
00294 
00295     /**
00296      * Helper function to add TX_POWER_LEVEL data to the advertising payload.
00297      *
00298      * @return BLE_ERROR_BUFFER_OVERFLOW if the specified data would cause the
00299      * advertising buffer to overflow, else BLE_ERROR_NONE.
00300      */
00301     ble_error_t addTxPower(int8_t txPower) {
00302         /* To Do: Basic error checking to make sure txPower is in range. */
00303         return addData(GapAdvertisingData::TX_POWER_LEVEL, (uint8_t *)&txPower, 1);
00304     }
00305 
00306     /**
00307      * Clears the payload and resets the payload length counter.
00308      */
00309     void        clear(void) {
00310         memset(&_payload, 0, GAP_ADVERTISING_DATA_MAX_PAYLOAD);
00311         _payloadLen = 0;
00312     }
00313 
00314     /**
00315      * Returns a pointer to the current payload.
00316      */
00317     const uint8_t *getPayload(void) const {
00318         return _payload;
00319     }
00320 
00321     /**
00322      * Returns the current payload length (0..31 bytes).
00323      */
00324     uint8_t     getPayloadLen(void) const {
00325         return _payloadLen;
00326     }
00327 
00328     /**
00329      * Returns the 16-bit appearance value for this device.
00330      */
00331     uint16_t    getAppearance(void) const {
00332         return (uint16_t)_appearance;
00333     }
00334 
00335     /**
00336      * Search advertisement data for field.
00337      * Returns pointer to the first element in the field if found, NULL otherwise.
00338      * Where the first element is the length of the field.
00339      */
00340     const uint8_t* findField(DataType_t type) const {
00341         return findField(type);
00342     }
00343 
00344 private:
00345     /**
00346      * Append advertising data based on the specified AD type (see DataType)
00347      */
00348     ble_error_t appendField(DataType advDataType, const uint8_t *payload, uint8_t len)
00349     {
00350         /* Make sure we don't exceed the 31 byte payload limit */
00351         if (_payloadLen + len + 2 > GAP_ADVERTISING_DATA_MAX_PAYLOAD) {
00352             return BLE_ERROR_BUFFER_OVERFLOW;
00353         }
00354 
00355         /* Field length. */
00356         memset(&_payload[_payloadLen], len + 1, 1);
00357         _payloadLen++;
00358 
00359         /* Field ID. */
00360         memset(&_payload[_payloadLen], (uint8_t)advDataType, 1);
00361         _payloadLen++;
00362 
00363         /* Payload. */
00364         memcpy(&_payload[_payloadLen], payload, len);
00365         _payloadLen += len;
00366 
00367         return BLE_ERROR_NONE;
00368     }
00369 
00370     /**
00371      * Search advertisement data for field.
00372      * Returns pointer to the first element in the field if found, NULL otherwise.
00373      * Where the first element is the length of the field.
00374      */
00375     uint8_t* findField(DataType_t type) {
00376         // scan through advertisement data
00377         for (uint8_t idx = 0; idx < _payloadLen; ) {
00378             uint8_t fieldType = _payload[idx + 1];
00379 
00380             if (fieldType == type) {
00381                 return &_payload[idx];
00382             }
00383 
00384             // advance to next field
00385             idx += _payload[idx] + 1;
00386         }
00387 
00388         // field not found
00389         return NULL;
00390     }
00391 
00392     /**
00393      * Given the a pointer to a field in the advertising payload it replaces
00394      * the existing data in the field with the supplied data.
00395      *
00396      * When the specified AD type is INCOMPLETE_LIST_16BIT_SERVICE_IDS,
00397      * COMPLETE_LIST_16BIT_SERVICE_IDS, INCOMPLETE_LIST_32BIT_SERVICE_IDS,
00398      * COMPLETE_LIST_32BIT_SERVICE_IDS, INCOMPLETE_LIST_128BIT_SERVICE_IDS,
00399      * COMPLETE_LIST_128BIT_SERVICE_IDS or LIST_128BIT_SOLICITATION_IDS the
00400      * supplied value is appended to the values previously added to the
00401      * payload.
00402      *
00403      * Returns BLE_ERROR_NONE on success.
00404      */
00405     ble_error_t addField(DataType_t advDataType, const uint8_t *payload, uint8_t len, uint8_t* field)
00406     {
00407         ble_error_t result = BLE_ERROR_BUFFER_OVERFLOW;
00408 
00409         switch(advDataType) {
00410             // These fields will have the new data appended if there is sufficient space
00411             case INCOMPLETE_LIST_16BIT_SERVICE_IDS:
00412             case COMPLETE_LIST_16BIT_SERVICE_IDS:
00413             case INCOMPLETE_LIST_32BIT_SERVICE_IDS:
00414             case COMPLETE_LIST_32BIT_SERVICE_IDS:
00415             case INCOMPLETE_LIST_128BIT_SERVICE_IDS:
00416             case COMPLETE_LIST_128BIT_SERVICE_IDS:
00417             case LIST_128BIT_SOLICITATION_IDS: {
00418                 // check if data fits
00419                 if ((_payloadLen + len) <= GAP_ADVERTISING_DATA_MAX_PAYLOAD) {
00420                     // make room for new field by moving the remainder of the
00421                     // advertisement payload "to the right" starting after the
00422                     // TYPE field.
00423                     uint8_t* end = &_payload[_payloadLen];
00424 
00425                     while (&field[1] < end) {
00426                         end[len] = *end;
00427                         end--;
00428                     }
00429 
00430                     // insert new data
00431                     for (uint8_t idx = 0; idx < len; idx++) {
00432                         field[2 + idx] = payload[idx];
00433                     }
00434 
00435                     // increment lengths
00436                     field[0] += len;
00437                     _payloadLen += len;
00438 
00439                     result = BLE_ERROR_NONE;
00440                 }
00441 
00442                 break;
00443             }
00444             //  These fields will be overwritten with the new value
00445             default: {
00446                 result = updateField(advDataType, payload, len, field);
00447 
00448                 break;
00449             }
00450         }
00451 
00452         return result;
00453     }
00454 
00455     /**
00456      * Given the a pointer to a field in the advertising payload it replaces
00457      * the existing data in the field with the supplied data.
00458      * Returns BLE_ERROR_NONE on success.
00459      */
00460     ble_error_t updateField(DataType_t advDataType, const uint8_t *payload, uint8_t len, uint8_t* field)
00461     {
00462         ble_error_t result = BLE_ERROR_BUFFER_OVERFLOW;
00463         uint8_t dataLength = field[0] - 1;
00464 
00465         // new data has same length, do in-order replacement
00466         if (len == dataLength) {
00467             for (uint8_t idx = 0; idx < dataLength; idx++) {
00468                 field[2 + idx] = payload[idx];
00469             }
00470 
00471             result = BLE_ERROR_NONE;
00472         } else {
00473             // check if data fits
00474             if ((_payloadLen - dataLength + len) <= GAP_ADVERTISING_DATA_MAX_PAYLOAD) {
00475 
00476                 // remove old field
00477                 while ((field + dataLength + 2) < &_payload[_payloadLen]) {
00478                     *field = field[dataLength + 2];
00479                     field++;
00480                 }
00481 
00482                 // reduce length
00483                 _payloadLen -= dataLength + 2;
00484 
00485                 // add new field
00486                 result = appendField(advDataType, payload, len);
00487             }
00488         }
00489 
00490         return result;
00491     }
00492 
00493     uint8_t  _payload[GAP_ADVERTISING_DATA_MAX_PAYLOAD];
00494     uint8_t  _payloadLen;
00495     uint16_t _appearance;
00496 };
00497 
00498 #endif // ifndef __GAP_ADVERTISING_DATA_H__