1 /*
2 * Copyright (c) 2024 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15 #include "usb_ddk_permission.h"
16
17 #include <hdf_log.h>
18 #include <dlfcn.h>
19 #include <mutex>
20
21 #include "ipc_skeleton.h"
22
23 namespace OHOS {
24 namespace HDI {
25 namespace Usb {
26 namespace Ddk {
27 namespace V1_0 {
28 using VerifyAccessTokenFunc = int(*)(uint32_t callerToken, const std::string &permissionName);
29
30 static constexpr int PERMISSION_GRANTED = 0;
31
32 static void *g_libHandle = nullptr;
33 static VerifyAccessTokenFunc g_verifyAccessToken = nullptr;
34
35 static std::mutex g_mutex;
36
InitVerifyAccessToken()37 static void InitVerifyAccessToken()
38 {
39 if (g_verifyAccessToken != nullptr) {
40 return;
41 }
42
43 g_libHandle = dlopen("libusb_ddk_dynamic_library_wrapper.z.so", RTLD_LAZY);
44 if (g_libHandle == nullptr) {
45 HDF_LOGE("%{public}s dlopen failed: %{public}s", __func__, dlerror());
46 return;
47 }
48
49 void *funcPtr = dlsym(g_libHandle, "VerifyAccessToken");
50 if (funcPtr == nullptr) {
51 HDF_LOGE("%{public}s dlsym failed: %{public}s", __func__, dlerror());
52 dlclose(g_libHandle);
53 g_libHandle = nullptr;
54 return;
55 }
56
57 g_verifyAccessToken = reinterpret_cast<VerifyAccessTokenFunc>(funcPtr);
58 }
59
Reset()60 void DdkPermissionManager::Reset()
61 {
62 std::lock_guard<std::mutex> lock(g_mutex);
63 g_verifyAccessToken = nullptr;
64 if (g_libHandle != nullptr) {
65 dlclose(g_libHandle);
66 g_libHandle = nullptr;
67 }
68 }
69
VerifyPermission(const std::string &permissionName)70 bool DdkPermissionManager::VerifyPermission(const std::string &permissionName)
71 {
72 std::lock_guard<std::mutex> lock(g_mutex);
73 InitVerifyAccessToken();
74 if (g_verifyAccessToken == nullptr) {
75 return false;
76 }
77
78 uint32_t callerToken = IPCSkeleton::GetCallingTokenID();
79 int result = g_verifyAccessToken(callerToken, permissionName);
80 HDF_LOGI("%{public}s VerifyAccessToken: %{public}d", __func__, result);
81 return result == PERMISSION_GRANTED;
82 }
83 } // namespace V1_0
84 } // namespace Ddk
85 } // namespace Usb
86 } // namespace HDI
87 } // namespace OHOS