xref: /nrf52832-nimble/packages/NimBLE-latest/apps/bleprph/src/gatt_svr.c (revision 042d53a763ad75cb1465103098bb88c245d95138)
1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one
3  * or more contributor license agreements.  See the NOTICE file
4  * distributed with this work for additional information
5  * regarding copyright ownership.  The ASF licenses this file
6  * to you under the Apache License, Version 2.0 (the
7  * "License"); you may not use this file except in compliance
8  * with the License.  You may obtain a copy of the License at
9  *
10  *  http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing,
13  * software distributed under the License is distributed on an
14  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15  * KIND, either express or implied.  See the License for the
16  * specific language governing permissions and limitations
17  * under the License.
18  */
19 
20 #include <assert.h>
21 #include <stdio.h>
22 #include <string.h>
23 #include "host/ble_hs.h"
24 #include "host/ble_uuid.h"
25 #include "bleprph.h"
26 
27 /**
28  * The vendor specific security test service consists of two characteristics:
29  *     o random-number-generator: generates a random 32-bit number each time
30  *       it is read.  This characteristic can only be read over an encrypted
31  *       connection.
32  *     o static-value: a single-byte characteristic that can always be read,
33  *       but can only be written over an encrypted connection.
34  */
35 
36 /* 59462f12-9543-9999-12c8-58b459a2712d */
37 static const ble_uuid128_t gatt_svr_svc_sec_test_uuid =
38     BLE_UUID128_INIT(0x2d, 0x71, 0xa2, 0x59, 0xb4, 0x58, 0xc8, 0x12,
39                      0x99, 0x99, 0x43, 0x95, 0x12, 0x2f, 0x46, 0x59);
40 
41 /* 5c3a659e-897e-45e1-b016-007107c96df6 */
42 static const ble_uuid128_t gatt_svr_chr_sec_test_rand_uuid =
43         BLE_UUID128_INIT(0xf6, 0x6d, 0xc9, 0x07, 0x71, 0x00, 0x16, 0xb0,
44                          0xe1, 0x45, 0x7e, 0x89, 0x9e, 0x65, 0x3a, 0x5c);
45 
46 /* 5c3a659e-897e-45e1-b016-007107c96df7 */
47 static const ble_uuid128_t gatt_svr_chr_sec_test_static_uuid =
48         BLE_UUID128_INIT(0xf7, 0x6d, 0xc9, 0x07, 0x71, 0x00, 0x16, 0xb0,
49                          0xe1, 0x45, 0x7e, 0x89, 0x9e, 0x65, 0x3a, 0x5c);
50 
51 static uint8_t gatt_svr_sec_test_static_val;
52 
53 static int
54 gatt_svr_chr_access_sec_test(uint16_t conn_handle, uint16_t attr_handle,
55                              struct ble_gatt_access_ctxt *ctxt,
56                              void *arg);
57 
58 static const struct ble_gatt_svc_def gatt_svr_svcs[] = {
59     {
60         /*** Service: Security test. */
61         .type = BLE_GATT_SVC_TYPE_PRIMARY,
62         .uuid = &gatt_svr_svc_sec_test_uuid.u,
63         .characteristics = (struct ble_gatt_chr_def[]) { {
64             /*** Characteristic: Random number generator. */
65             .uuid = &gatt_svr_chr_sec_test_rand_uuid.u,
66             .access_cb = gatt_svr_chr_access_sec_test,
67             .flags = BLE_GATT_CHR_F_READ | BLE_GATT_CHR_F_READ_ENC,
68         }, {
69             /*** Characteristic: Static value. */
70             .uuid = &gatt_svr_chr_sec_test_static_uuid.u,
71             .access_cb = gatt_svr_chr_access_sec_test,
72             .flags = BLE_GATT_CHR_F_READ |
73                      BLE_GATT_CHR_F_WRITE | BLE_GATT_CHR_F_WRITE_ENC,
74         }, {
75             0, /* No more characteristics in this service. */
76         } },
77     },
78 
79     {
80         0, /* No more services. */
81     },
82 };
83 
84 static int
gatt_svr_chr_write(struct os_mbuf * om,uint16_t min_len,uint16_t max_len,void * dst,uint16_t * len)85 gatt_svr_chr_write(struct os_mbuf *om, uint16_t min_len, uint16_t max_len,
86                    void *dst, uint16_t *len)
87 {
88     uint16_t om_len;
89     int rc;
90 
91     om_len = OS_MBUF_PKTLEN(om);
92     if (om_len < min_len || om_len > max_len) {
93         return BLE_ATT_ERR_INVALID_ATTR_VALUE_LEN;
94     }
95 
96     rc = ble_hs_mbuf_to_flat(om, dst, max_len, len);
97     if (rc != 0) {
98         return BLE_ATT_ERR_UNLIKELY;
99     }
100 
101     return 0;
102 }
103 
104 static int
gatt_svr_chr_access_sec_test(uint16_t conn_handle,uint16_t attr_handle,struct ble_gatt_access_ctxt * ctxt,void * arg)105 gatt_svr_chr_access_sec_test(uint16_t conn_handle, uint16_t attr_handle,
106                              struct ble_gatt_access_ctxt *ctxt,
107                              void *arg)
108 {
109     const ble_uuid_t *uuid;
110     int rand_num;
111     int rc;
112 
113     uuid = ctxt->chr->uuid;
114 
115     /* Determine which characteristic is being accessed by examining its
116      * 128-bit UUID.
117      */
118 
119     if (ble_uuid_cmp(uuid, &gatt_svr_chr_sec_test_rand_uuid.u) == 0) {
120         assert(ctxt->op == BLE_GATT_ACCESS_OP_READ_CHR);
121 
122         /* Respond with a 32-bit random number. */
123         rand_num = rand();
124         rc = os_mbuf_append(ctxt->om, &rand_num, sizeof rand_num);
125         return rc == 0 ? 0 : BLE_ATT_ERR_INSUFFICIENT_RES;
126     }
127 
128     if (ble_uuid_cmp(uuid, &gatt_svr_chr_sec_test_static_uuid.u) == 0) {
129         switch (ctxt->op) {
130         case BLE_GATT_ACCESS_OP_READ_CHR:
131             rc = os_mbuf_append(ctxt->om, &gatt_svr_sec_test_static_val,
132                                 sizeof gatt_svr_sec_test_static_val);
133             return rc == 0 ? 0 : BLE_ATT_ERR_INSUFFICIENT_RES;
134 
135         case BLE_GATT_ACCESS_OP_WRITE_CHR:
136             rc = gatt_svr_chr_write(ctxt->om,
137                                     sizeof gatt_svr_sec_test_static_val,
138                                     sizeof gatt_svr_sec_test_static_val,
139                                     &gatt_svr_sec_test_static_val, NULL);
140             return rc;
141 
142         default:
143             assert(0);
144             return BLE_ATT_ERR_UNLIKELY;
145         }
146     }
147 
148     /* Unknown characteristic; the nimble stack should not have called this
149      * function.
150      */
151     assert(0);
152     return BLE_ATT_ERR_UNLIKELY;
153 }
154 
155 void
gatt_svr_register_cb(struct ble_gatt_register_ctxt * ctxt,void * arg)156 gatt_svr_register_cb(struct ble_gatt_register_ctxt *ctxt, void *arg)
157 {
158     char buf[BLE_UUID_STR_LEN];
159 
160     switch (ctxt->op) {
161     case BLE_GATT_REGISTER_OP_SVC:
162         MODLOG_DFLT(DEBUG, "registered service %s with handle=%d\n",
163                     ble_uuid_to_str(ctxt->svc.svc_def->uuid, buf),
164                     ctxt->svc.handle);
165         break;
166 
167     case BLE_GATT_REGISTER_OP_CHR:
168         MODLOG_DFLT(DEBUG, "registering characteristic %s with "
169                            "def_handle=%d val_handle=%d\n",
170                     ble_uuid_to_str(ctxt->chr.chr_def->uuid, buf),
171                     ctxt->chr.def_handle,
172                     ctxt->chr.val_handle);
173         break;
174 
175     case BLE_GATT_REGISTER_OP_DSC:
176         MODLOG_DFLT(DEBUG, "registering descriptor %s with handle=%d\n",
177                     ble_uuid_to_str(ctxt->dsc.dsc_def->uuid, buf),
178                     ctxt->dsc.handle);
179         break;
180 
181     default:
182         assert(0);
183         break;
184     }
185 }
186 
187 int
gatt_svr_init(void)188 gatt_svr_init(void)
189 {
190     int rc;
191 
192     rc = ble_gatts_count_cfg(gatt_svr_svcs);
193     if (rc != 0) {
194         return rc;
195     }
196 
197     rc = ble_gatts_add_svcs(gatt_svr_svcs);
198     if (rc != 0) {
199         return rc;
200     }
201 
202     return 0;
203 }
204