1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 24 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "att_db_util.c" 39 40 #include <string.h> 41 #include <stdlib.h> 42 43 #include "ble/att_db_util.h" 44 #include "ble/att_db.h" 45 #include "ble/core.h" 46 #include "btstack_util.h" 47 #include "btstack_debug.h" 48 #include "bluetooth.h" 49 50 // ATT DB Storage 51 #ifndef HAVE_MALLOC 52 #ifdef MAX_ATT_DB_SIZE 53 static uint8_t att_db_storage[MAX_ATT_DB_SIZE]; 54 #else 55 #error Neither HAVE_MALLOC nor MAX_ATT_DB_SIZE is defined. 56 #endif 57 #endif 58 59 static uint8_t * att_db; 60 static uint16_t att_db_size; 61 static uint16_t att_db_max_size; 62 static uint16_t att_db_next_handle; 63 64 static void att_db_util_set_end_tag(void){ 65 // end tag 66 att_db[att_db_size] = 0; 67 att_db[att_db_size+1] = 0; 68 } 69 70 void att_db_util_init(void){ 71 #ifdef HAVE_MALLOC 72 att_db = (uint8_t*) malloc(128); 73 att_db_max_size = 128; 74 #else 75 att_db = att_db_storage; 76 att_db_max_size = sizeof(att_db_storage); 77 #endif 78 // store att version 79 att_db[0] = ATT_DB_VERSION; 80 att_db_size = 1; 81 att_db_next_handle = 1; 82 att_db_util_set_end_tag(); 83 } 84 85 /** 86 * asserts that the requested amount of bytes can be stored in the att_db 87 * @returns TRUE if space is available 88 */ 89 static int att_db_util_assert_space(uint16_t size){ 90 size += 2; // for end tag 91 if ((att_db_size + size) <= att_db_max_size) return 1; 92 #ifdef HAVE_MALLOC 93 int new_size = att_db_size + att_db_size / 2; 94 uint8_t * new_db = (uint8_t*) realloc(att_db, new_size); 95 if (!new_db) { 96 log_error("att_db: realloc failed"); 97 return 0; 98 } 99 att_db = new_db; 100 att_db_max_size = new_size; 101 att_set_db(att_db); // Update att_db with the new db 102 return 1; 103 #else 104 log_error("att_db: out of memory"); 105 return 0; 106 #endif 107 } 108 109 // attribute size in bytes (16), flags(16), handle (16), uuid (16/128), value(...) 110 111 // db endds with 0x00 0x00 112 113 static void att_db_util_add_attribute_uuid16(uint16_t uuid16, uint16_t flags, uint8_t * data, uint16_t data_len){ 114 int size = 2 + 2 + 2 + 2 + data_len; 115 if (!att_db_util_assert_space(size)) return; 116 little_endian_store_16(att_db, att_db_size, size); 117 att_db_size += 2; 118 little_endian_store_16(att_db, att_db_size, flags); 119 att_db_size += 2; 120 little_endian_store_16(att_db, att_db_size, att_db_next_handle); 121 att_db_size += 2; 122 att_db_next_handle++; 123 little_endian_store_16(att_db, att_db_size, uuid16); 124 att_db_size += 2; 125 (void)memcpy(&att_db[att_db_size], data, data_len); 126 att_db_size += data_len; 127 att_db_util_set_end_tag(); 128 } 129 130 static void att_db_util_add_attribute_uuid128(const uint8_t * uuid128, uint16_t flags, uint8_t * data, uint16_t data_len){ 131 int size = 2 + 2 + 2 + 16 + data_len; 132 if (!att_db_util_assert_space(size)) return; 133 flags |= ATT_PROPERTY_UUID128; 134 little_endian_store_16(att_db, att_db_size, size); 135 att_db_size += 2; 136 little_endian_store_16(att_db, att_db_size, flags); 137 att_db_size += 2; 138 little_endian_store_16(att_db, att_db_size, att_db_next_handle); 139 att_db_size += 2; 140 att_db_next_handle++; 141 reverse_128(uuid128, &att_db[att_db_size]); 142 att_db_size += 16; 143 (void)memcpy(&att_db[att_db_size], data, data_len); 144 att_db_size += data_len; 145 att_db_util_set_end_tag(); 146 } 147 148 uint16_t att_db_util_add_service_uuid16(uint16_t uuid16){ 149 uint8_t buffer[2]; 150 little_endian_store_16(buffer, 0, uuid16); 151 uint16_t service_handle = att_db_next_handle; 152 att_db_util_add_attribute_uuid16(GATT_PRIMARY_SERVICE_UUID, ATT_PROPERTY_READ, buffer, 2); 153 return service_handle; 154 } 155 156 uint16_t att_db_util_add_service_uuid128(const uint8_t * uuid128){ 157 uint8_t buffer[16]; 158 reverse_128(uuid128, buffer); 159 uint16_t service_handle = att_db_next_handle; 160 att_db_util_add_attribute_uuid16(GATT_PRIMARY_SERVICE_UUID, ATT_PROPERTY_READ, buffer, 16); 161 return service_handle; 162 } 163 164 static void att_db_util_add_client_characteristic_configuration(uint16_t flags){ 165 uint8_t buffer[2]; 166 // drop permission for read (0xc00), keep write permissions (0x0091) 167 flags = (flags & 0x1f391) | ATT_PROPERTY_READ | ATT_PROPERTY_WRITE | ATT_PROPERTY_DYNAMIC; 168 little_endian_store_16(buffer, 0, 0); 169 att_db_util_add_attribute_uuid16(GATT_CLIENT_CHARACTERISTICS_CONFIGURATION, flags, buffer, 2); 170 } 171 172 static uint16_t att_db_util_encode_permissions(uint16_t properties, uint8_t read_permission, uint8_t write_permission){ 173 // drop Broadcast (0x01), Notify (0x10), Indicate (0x20), Extended Attributes (0x80) - not used for flags 174 uint16_t flags = properties & 0xfff4e; 175 // if encryption requested, set encryption key size to 16 176 if ((read_permission > ATT_SECURITY_NONE) || (write_permission > ATT_SECURITY_NONE)){ 177 flags |= 0xf000; 178 } 179 // map SC requirement 180 if (read_permission == ATT_SECURITY_AUTHENTICATED_SC){ 181 read_permission = ATT_SECURITY_AUTHENTICATED; 182 flags |= ATT_PROPERTY_READ_PERMISSION_SC; 183 } 184 if (write_permission == ATT_SECURITY_AUTHENTICATED_SC){ 185 write_permission = ATT_SECURITY_AUTHENTICATED; 186 flags |= ATT_PROPERTY_WRITE_PERMISSION_SC; 187 } 188 // encode read/write security levels 189 if (read_permission & 1){ 190 flags |= ATT_PROPERTY_READ_PERMISSION_BIT_0; 191 } 192 if (read_permission & 2){ 193 flags |= ATT_PROPERTY_READ_PERMISSION_BIT_1; 194 } 195 if (write_permission & 1){ 196 flags |= ATT_PROPERTY_WRITE_PERMISSION_BIT_0; 197 } 198 if (write_permission & 2){ 199 flags |= ATT_PROPERTY_WRITE_PERMISSION_BIT_1; 200 } 201 return flags; 202 } 203 204 uint16_t att_db_util_add_characteristic_uuid16(uint16_t uuid16, uint16_t properties, uint8_t read_permission, uint8_t write_permission, uint8_t * data, uint16_t data_len){ 205 uint8_t buffer[5]; 206 buffer[0] = properties; 207 little_endian_store_16(buffer, 1, att_db_next_handle + 1); 208 little_endian_store_16(buffer, 3, uuid16); 209 att_db_util_add_attribute_uuid16(GATT_CHARACTERISTICS_UUID, ATT_PROPERTY_READ, buffer, sizeof(buffer)); 210 uint16_t flags = att_db_util_encode_permissions(properties, read_permission, write_permission); 211 uint16_t value_handle = att_db_next_handle; 212 att_db_util_add_attribute_uuid16(uuid16, flags, data, data_len); 213 if (properties & (ATT_PROPERTY_NOTIFY | ATT_PROPERTY_INDICATE)){ 214 att_db_util_add_client_characteristic_configuration(flags); 215 } 216 return value_handle; 217 } 218 219 uint16_t att_db_util_add_characteristic_uuid128(const uint8_t * uuid128, uint16_t properties, uint8_t read_permission, uint8_t write_permission, uint8_t * data, uint16_t data_len){ 220 uint8_t buffer[19]; 221 buffer[0] = properties; 222 little_endian_store_16(buffer, 1, att_db_next_handle + 1); 223 reverse_128(uuid128, &buffer[3]); 224 att_db_util_add_attribute_uuid16(GATT_CHARACTERISTICS_UUID, ATT_PROPERTY_READ, buffer, sizeof(buffer)); 225 uint16_t flags = att_db_util_encode_permissions(properties, read_permission, write_permission); 226 uint16_t value_handle = att_db_next_handle; 227 att_db_util_add_attribute_uuid128(uuid128, flags, data, data_len); 228 if (properties & (ATT_PROPERTY_NOTIFY | ATT_PROPERTY_INDICATE)){ 229 att_db_util_add_client_characteristic_configuration(flags); 230 } 231 return value_handle; 232 } 233 234 uint16_t att_db_util_add_descriptor_uuid16(uint16_t uuid16, uint16_t properties, uint8_t read_permission, uint8_t write_permission, uint8_t * data, uint16_t data_len){ 235 uint16_t descriptor_handler = att_db_next_handle; 236 uint16_t flags = att_db_util_encode_permissions(properties, read_permission, write_permission); 237 att_db_util_add_attribute_uuid16(uuid16, flags, data, data_len); 238 return descriptor_handler; 239 } 240 241 uint16_t att_db_util_add_descriptor_uuid128(const uint8_t * uuid128, uint16_t properties, uint8_t read_permission, uint8_t write_permission, uint8_t * data, uint16_t data_len){ 242 uint16_t descriptor_handler = att_db_next_handle; 243 uint16_t flags = att_db_util_encode_permissions(properties, read_permission, write_permission); 244 att_db_util_add_attribute_uuid128(uuid128, flags, data, data_len); 245 return descriptor_handler; 246 } 247 248 uint8_t * att_db_util_get_address(void){ 249 return att_db; 250 } 251 252 uint16_t att_db_util_get_size(void){ 253 return att_db_size + 2; // end tag 254 } 255