wearable/attrib/gatt-service.c

   1 /*
   2  *
   3  *  BlueZ - Bluetooth protocol stack for Linux
   4  *
   5  *  Copyright (C) 2011  Nokia Corporation
   6  *  Copyright (C) 2011  Marcel Holtmann <marcel@holtmann.org>
   7  *
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or
  12  *  (at your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful,
  15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *  GNU General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License
  20  *  along with this program; if not, write to the Free Software
  21  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  22  *
  23  */
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include <config.h>
  27 #endif
  28
  29 #include <glib.h>
  30 #include <bluetooth/uuid.h>
  31 #include <bluetooth/sdp.h>
  32 #include <adapter.h>
  33
  34 #include "gattrib.h"
  35 #include "att.h"
  36 #include "gatt.h"
  37 #include "att-database.h"
  38 #include "attrib-server.h"
  39 #include "gatt-service.h"
  40 #include "log.h"
  41
  42 struct gatt_info {
  43         bt_uuid_t uuid;
  44         uint8_t props;
  45         int authentication;
  46         int authorization;
  47         GSList *callbacks;
  48         unsigned int num_attrs;
  49         uint16_t *value_handle;
  50         uint16_t *ccc_handle;
  51 };
  52
  53 struct attrib_cb {
  54         attrib_event_t event;
  55         void *fn;
  56         void *user_data;
  57 };
  58
  59 static GSList *parse_opts(gatt_option opt1, va_list args)
  60 {
  61         gatt_option opt = opt1;
  62         struct gatt_info *info;
  63         struct attrib_cb *cb;
  64         GSList *l = NULL;
  65
  66         info = g_new0(struct gatt_info, 1);
  67         l = g_slist_append(l, info);
  68
  69         while (opt != GATT_OPT_INVALID) {
  70                 switch (opt) {
  71                 case GATT_OPT_CHR_UUID:
  72                         bt_uuid16_create(&info->uuid, va_arg(args, int));
  73                         /* characteristic declaration and value */
  74                         info->num_attrs += 2;
  75                         break;
  76                 case GATT_OPT_CHR_PROPS:
  77                         info->props = va_arg(args, int);
  78
  79                         if (info->props & (ATT_CHAR_PROPER_NOTIFY |
  80                                                 ATT_CHAR_PROPER_INDICATE))
  81                                 /* client characteristic configuration */
  82                                 info->num_attrs += 1;
  83
  84                         /* TODO: "Extended Properties" property requires a
  85                          * descriptor, but it is not supported yet. */
  86                         break;
  87                 case GATT_OPT_CHR_VALUE_CB:
  88                         cb = g_new0(struct attrib_cb, 1);
  89                         cb->event = va_arg(args, attrib_event_t);
  90                         cb->fn = va_arg(args, void *);
  91                         cb->user_data = va_arg(args, void *);
  92                         info->callbacks = g_slist_append(info->callbacks, cb);
  93                         break;
  94                 case GATT_OPT_CHR_VALUE_GET_HANDLE:
  95                         info->value_handle = va_arg(args, void *);
  96                         break;
  97                 case GATT_OPT_CCC_GET_HANDLE:
  98                         info->ccc_handle = va_arg(args, void *);
  99                         break;
 100                 case GATT_OPT_CHR_AUTHENTICATION:
 101                         info->authentication = va_arg(args, gatt_option);
 102                         break;
 103                 case GATT_OPT_CHR_AUTHORIZATION:
 104                         info->authorization = va_arg(args, gatt_option);
 105                         break;
 106                 default:
 107                         error("Invalid option: %d", opt);
 108                 }
 109
 110                 opt = va_arg(args, gatt_option);
 111                 if (opt == GATT_OPT_CHR_UUID) {
 112                         info = g_new0(struct gatt_info, 1);
 113                         l = g_slist_append(l, info);
 114                 }
 115         }
 116
 117         return l;
 118 }
 119
 120 static struct attribute *add_service_declaration(struct btd_adapter *adapter,
 121                                 uint16_t handle, uint16_t svc, bt_uuid_t *uuid)
 122 {
 123         bt_uuid_t bt_uuid;
 124         uint8_t atval[16];
 125         int len;
 126
 127         if (uuid->type == BT_UUID16) {
 128                 att_put_u16(uuid->value.u16, &atval[0]);
 129                 len = 2;
 130         } else if (uuid->type == BT_UUID128) {
 131                 att_put_u128(uuid->value.u128, &atval[0]);
 132                 len = 16;
 133         } else
 134                 return NULL;
 135
 136         bt_uuid16_create(&bt_uuid, svc);
 137
 138         return attrib_db_add(adapter, handle, &bt_uuid, ATT_NONE,
 139                                                 ATT_NOT_PERMITTED, atval, len);
 140 }
 141
 142 static int att_read_reqs(int authorization, int authentication, uint8_t props)
 143 {
 144         if (authorization == GATT_CHR_VALUE_READ ||
 145                                 authorization == GATT_CHR_VALUE_BOTH)
 146                 return ATT_AUTHORIZATION;
 147         else if (authentication == GATT_CHR_VALUE_READ ||
 148                                 authentication == GATT_CHR_VALUE_BOTH)
 149                 return ATT_AUTHENTICATION;
 150         else if (!(props & ATT_CHAR_PROPER_READ))
 151                 return ATT_NOT_PERMITTED;
 152
 153         return ATT_NONE;
 154 }
 155
 156 static int att_write_reqs(int authorization, int authentication, uint8_t props)
 157 {
 158         if (authorization == GATT_CHR_VALUE_WRITE ||
 159                                 authorization == GATT_CHR_VALUE_BOTH)
 160                 return ATT_AUTHORIZATION;
 161         else if (authentication == GATT_CHR_VALUE_WRITE ||
 162                                 authentication == GATT_CHR_VALUE_BOTH)
 163                 return ATT_AUTHENTICATION;
 164         else if (!(props & (ATT_CHAR_PROPER_WRITE |
 165                                         ATT_CHAR_PROPER_WRITE_WITHOUT_RESP)))
 166                 return ATT_NOT_PERMITTED;
 167
 168         return ATT_NONE;
 169 }
 170
 171 static gint find_callback(gconstpointer a, gconstpointer b)
 172 {
 173         const struct attrib_cb *cb = a;
 174         unsigned int event = GPOINTER_TO_UINT(b);
 175
 176         return cb->event - event;
 177 }
 178
 179 static gboolean add_characteristic(struct btd_adapter *adapter,
 180                                 uint16_t *handle, struct gatt_info *info)
 181 {
 182         int read_reqs, write_reqs;
 183         uint16_t h = *handle;
 184         struct attribute *a;
 185         bt_uuid_t bt_uuid;
 186         uint8_t atval[5];
 187         GSList *l;
 188
 189         if (!info->uuid.value.u16 || !info->props) {
 190                 error("Characteristic UUID or properties are missing");
 191                 return FALSE;
 192         }
 193
 194         read_reqs = att_read_reqs(info->authorization, info->authentication,
 195                                                                 info->props);
 196         write_reqs = att_write_reqs(info->authorization, info->authentication,
 197                                                                 info->props);
 198
 199         /* TODO: static characteristic values are not supported, therefore a
 200          * callback must be always provided if a read/write property is set */
 201         if (read_reqs != ATT_NOT_PERMITTED) {
 202                 gpointer reqs = GUINT_TO_POINTER(ATTRIB_READ);
 203
 204                 if (!g_slist_find_custom(info->callbacks, reqs,
 205                                                         find_callback)) {
 206                         error("Callback for read required");
 207                         return FALSE;
 208                 }
 209         }
 210
 211         if (write_reqs != ATT_NOT_PERMITTED) {
 212                 gpointer reqs = GUINT_TO_POINTER(ATTRIB_WRITE);
 213
 214                 if (!g_slist_find_custom(info->callbacks, reqs,
 215                                                         find_callback)) {
 216                         error("Callback for write required");
 217                         return FALSE;
 218                 }
 219         }
 220
 221         /* characteristic declaration */
 222         bt_uuid16_create(&bt_uuid, GATT_CHARAC_UUID);
 223         atval[0] = info->props;
 224         att_put_u16(h + 1, &atval[1]);
 225         att_put_u16(info->uuid.value.u16, &atval[3]);
 226         if (attrib_db_add(adapter, h++, &bt_uuid, ATT_NONE, ATT_NOT_PERMITTED,
 227                                                 atval, sizeof(atval)) == NULL)
 228                 return FALSE;
 229
 230         /* characteristic value */
 231         a = attrib_db_add(adapter, h++, &info->uuid, read_reqs, write_reqs,
 232                                                                 NULL, 0);
 233         if (a == NULL)
 234                 return FALSE;
 235
 236         for (l = info->callbacks; l != NULL; l = l->next) {
 237                 struct attrib_cb *cb = l->data;
 238
 239                 switch (cb->event) {
 240                 case ATTRIB_READ:
 241                         a->read_cb = cb->fn;
 242                         break;
 243                 case ATTRIB_WRITE:
 244                         a->write_cb = cb->fn;
 245                         break;
 246                 }
 247
 248                 a->cb_user_data = cb->user_data;
 249         }
 250
 251         if (info->value_handle != NULL)
 252                 *info->value_handle = a->handle;
 253
 254         /* client characteristic configuration descriptor */
 255         if (info->props & (ATT_CHAR_PROPER_NOTIFY | ATT_CHAR_PROPER_INDICATE)) {
 256                 uint8_t cfg_val[2];
 257
 258                 bt_uuid16_create(&bt_uuid, GATT_CLIENT_CHARAC_CFG_UUID);
 259                 cfg_val[0] = 0x00;
 260                 cfg_val[1] = 0x00;
 261                 a = attrib_db_add(adapter, h++, &bt_uuid, ATT_NONE,
 262                                 ATT_AUTHENTICATION, cfg_val, sizeof(cfg_val));
 263                 if (a == NULL)
 264                         return FALSE;
 265
 266                 if (info->ccc_handle != NULL)
 267                         *info->ccc_handle = a->handle;
 268         }
 269
 270         *handle = h;
 271
 272         return TRUE;
 273 }
 274
 275 static void free_gatt_info(void *data)
 276 {
 277         struct gatt_info *info = data;
 278
 279         g_slist_free_full(info->callbacks, g_free);
 280         g_free(info);
 281 }
 282
 283 static void service_attr_del(struct btd_adapter *adapter, uint16_t start_handle,
 284                                                         uint16_t end_handle)
 285 {
 286         uint16_t handle;
 287
 288         for (handle = start_handle; handle <= end_handle; handle++)
 289                 if (attrib_db_del(adapter, handle) < 0)
 290                         error("Can't delete handle 0x%04x", handle);
 291 }
 292
 293 gboolean gatt_service_add(struct btd_adapter *adapter, uint16_t uuid,
 294                                 bt_uuid_t *svc_uuid, gatt_option opt1, ...)
 295 {
 296         char uuidstr[MAX_LEN_UUID_STR];
 297         uint16_t start_handle, h;
 298         unsigned int size;
 299         va_list args;
 300         GSList *chrs, *l;
 301
 302         bt_uuid_to_string(svc_uuid, uuidstr, MAX_LEN_UUID_STR);
 303
 304         if (svc_uuid->type != BT_UUID16 && svc_uuid->type != BT_UUID128) {
 305                 error("Invalid service uuid: %s", uuidstr);
 306                 return FALSE;
 307         }
 308
 309         va_start(args, opt1);
 310         chrs = parse_opts(opt1, args);
 311         va_end(args);
 312
 313         /* calculate how many attributes are necessary for this service */
 314         for (l = chrs, size = 1; l != NULL; l = l->next) {
 315                 struct gatt_info *info = l->data;
 316                 size += info->num_attrs;
 317         }
 318
 319         start_handle = attrib_db_find_avail(adapter, svc_uuid, size);
 320         if (start_handle == 0) {
 321                 error("Not enough free handles to register service");
 322                 goto fail;
 323         }
 324
 325         DBG("New service: handle 0x%04x, UUID %s, %d attributes",
 326                                                 start_handle, uuidstr, size);
 327
 328         /* service declaration */
 329         h = start_handle;
 330         if (add_service_declaration(adapter, h++, uuid, svc_uuid) == NULL)
 331                 goto fail;
 332
 333         for (l = chrs; l != NULL; l = l->next) {
 334                 struct gatt_info *info = l->data;
 335
 336                 DBG("New characteristic: handle 0x%04x", h);
 337                 if (!add_characteristic(adapter, &h, info)) {
 338                         service_attr_del(adapter, start_handle, h - 1);
 339                         goto fail;
 340                 }
 341         }
 342
 343         g_assert(size < USHRT_MAX);
 344         g_assert(h - start_handle == (uint16_t) size);
 345         g_slist_free_full(chrs, free_gatt_info);
 346
 347         return TRUE;
 348
 349 fail:
 350         g_slist_free_full(chrs, free_gatt_info);
 351         return FALSE;
 352 }