1 /******************************************************************************
2  *
3  *  Copyright (C) 2015 Google, Inc.
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at:
8  *
9  *  http://www.apache.org/licenses/LICENSE-2.0
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  ******************************************************************************/
18 
19 #define LOG_TAG "bt_device_interop"
20 
21 #include <assert.h>
22 #include <string.h> // For memcmp
23 
24 #include "btcore/include/module.h"
25 #include "device/include/interop.h"
26 #include "device/include/interop_database.h"
27 #include "osi/include/allocator.h"
28 #include "osi/include/list.h"
29 #include "osi/include/log.h"
30 
31 #define CASE_RETURN_STR(const) case const: return #const;
32 
33 static list_t *interop_list = NULL;
34 
35 static const char* interop_feature_string_(const interop_feature_t feature);
36 static void interop_free_entry_(void *data);
37 static void interop_lazy_init_(void);
38 static bool interop_match_fixed_(const interop_feature_t feature, const bt_bdaddr_t *addr);
39 static bool interop_match_dynamic_(const interop_feature_t feature, const bt_bdaddr_t *addr);
40 
41 // Interface functions
42 
interop_match_addr(const interop_feature_t feature,const bt_bdaddr_t * addr)43 bool interop_match_addr(const interop_feature_t feature, const bt_bdaddr_t *addr) {
44   assert(addr);
45 
46   if (interop_match_fixed_(feature, addr) || interop_match_dynamic_(feature, addr)) {
47     char bdstr[20] = {0};
48     LOG_WARN(LOG_TAG, "%s() Device %s is a match for interop workaround %s.",
49           __func__, bdaddr_to_string(addr, bdstr, sizeof(bdstr)),
50                         interop_feature_string_(feature));
51     return true;
52   }
53 
54   return false;
55 }
56 
interop_match_name(const interop_feature_t feature,const char * name)57 bool interop_match_name(const interop_feature_t feature, const char *name) {
58   assert(name);
59 
60   const size_t db_size = sizeof(interop_name_database) / sizeof(interop_name_entry_t);
61   for (size_t i = 0; i != db_size; ++i) {
62     if (feature == interop_name_database[i].feature &&
63         strlen(name) >= interop_name_database[i].length &&
64         strncmp(name, interop_name_database[i].name, interop_name_database[i].length) == 0) {
65       return true;
66     }
67   }
68 
69   return false;
70 }
71 
interop_database_add(const uint16_t feature,const bt_bdaddr_t * addr,size_t length)72 void interop_database_add(const uint16_t feature, const bt_bdaddr_t *addr, size_t length) {
73   assert(addr);
74   assert(length > 0);
75   assert(length < sizeof(bt_bdaddr_t));
76 
77   interop_addr_entry_t *entry = osi_calloc(sizeof(interop_addr_entry_t));
78   memcpy(&entry->addr, addr, length);
79   entry->feature = feature;
80   entry->length = length;
81 
82   interop_lazy_init_();
83   list_append(interop_list, entry);
84 }
85 
interop_database_clear()86 void interop_database_clear() {
87   if (interop_list)
88     list_clear(interop_list);
89 }
90 
91 // Module life-cycle functions
92 
interop_clean_up(void)93 static future_t *interop_clean_up(void) {
94   list_free(interop_list);
95   interop_list = NULL;
96   return future_new_immediate(FUTURE_SUCCESS);
97 }
98 
99 EXPORT_SYMBOL module_t interop_module = {
100   .name = INTEROP_MODULE,
101   .init = NULL,
102   .start_up = NULL,
103   .shut_down = NULL,
104   .clean_up = interop_clean_up,
105   .dependencies = {NULL},
106 };
107 
108 // Local functions
109 
interop_feature_string_(const interop_feature_t feature)110 static const char* interop_feature_string_(const interop_feature_t feature) {
111   switch (feature) {
112     CASE_RETURN_STR(INTEROP_DISABLE_LE_SECURE_CONNECTIONS)
113     CASE_RETURN_STR(INTEROP_AUTO_RETRY_PAIRING)
114     CASE_RETURN_STR(INTEROP_DISABLE_ABSOLUTE_VOLUME)
115     CASE_RETURN_STR(INTEROP_DISABLE_AUTO_PAIRING)
116     CASE_RETURN_STR(INTEROP_KEYBOARD_REQUIRES_FIXED_PIN)
117     CASE_RETURN_STR(INTEROP_2MBPS_LINK_ONLY)
118   }
119 
120   return "UNKNOWN";
121 }
122 
interop_free_entry_(void * data)123 static void interop_free_entry_(void *data) {
124   interop_addr_entry_t *entry = (interop_addr_entry_t *)data;
125   osi_free(entry);
126 }
127 
interop_lazy_init_(void)128 static void interop_lazy_init_(void) {
129   if (interop_list == NULL) {
130     interop_list = list_new(interop_free_entry_);
131   }
132 }
133 
interop_match_dynamic_(const interop_feature_t feature,const bt_bdaddr_t * addr)134 static bool interop_match_dynamic_(const interop_feature_t feature, const bt_bdaddr_t *addr) {
135   if (interop_list == NULL || list_length(interop_list) == 0)
136     return false;
137 
138   const list_node_t *node = list_begin(interop_list);
139   while (node != list_end(interop_list)) {
140     interop_addr_entry_t *entry = list_node(node);
141     assert(entry);
142 
143     if (feature == entry->feature && memcmp(addr, &entry->addr, entry->length) == 0)
144       return true;
145 
146     node = list_next(node);
147   }
148   return false;
149 }
150 
interop_match_fixed_(const interop_feature_t feature,const bt_bdaddr_t * addr)151 static bool interop_match_fixed_(const interop_feature_t feature, const bt_bdaddr_t *addr) {
152   assert(addr);
153 
154   const size_t db_size = sizeof(interop_addr_database) / sizeof(interop_addr_entry_t);
155   for (size_t i = 0; i != db_size; ++i) {
156     if (feature == interop_addr_database[i].feature &&
157         memcmp(addr, &interop_addr_database[i].addr, interop_addr_database[i].length) == 0) {
158       return true;
159     }
160   }
161 
162   return false;
163 }
164