1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <errno.h>
18 #include <string.h>
19 #include <sys/socket.h>
20 #include <sys/types.h>
21 #include <unistd.h>
22
23 #include <android-base/logging.h>
24 #include <cutils/sockets.h>
25
26 #include <nvram/hal/nvram_device_adapter.h>
27 #include <nvram/messages/nvram_messages.h>
28
29 namespace {
30
31 constexpr char kFakeNvramControlSocketName[] = "nvram";
32
33 // This instantiates an |NvramManager| with the storage interface wired up with
34 // an in-memory implementation. This *DOES NOT* meet the persistence and tamper
35 // evidence requirements of the HAL, but is useful for demonstration and running
36 // tests against the |NvramManager| implementation.
37 class TestingNvramImplementation : public nvram::NvramImplementation {
38 public:
39 ~TestingNvramImplementation() override;
40
41 void Execute(const nvram::Request& request,
42 nvram::Response* response) override;
43
44 private:
45 // Connects the fake NVRAM control socket it it is not open already. Returns
46 // true if the channel is open, false on errors.
47 bool Connect();
48
49 // Sends a request to the fake NVRAM daemon. Returns true if successful, false
50 // on any I/O errors.
51 bool SendRequest(const nvram::Request& request, nvram::Response* response);
52
53 // A file descriptor of the socket connected to the fake NVRAM daemon.
54 int nvram_socket_fd_ = -1;
55
56 // The command buffer, used for encoding request and decoding responses.
57 uint8_t command_buffer_[4096];
58 };
59
~TestingNvramImplementation()60 TestingNvramImplementation::~TestingNvramImplementation() {
61 if (nvram_socket_fd_ != -1) {
62 // No need to handle EINTR specially here as bionic filters it out.
63 if (close(nvram_socket_fd_)) {
64 PLOG(ERROR) << "Failed to close NVRAM command socket";
65 }
66 nvram_socket_fd_ = -1;
67 }
68 }
69
Execute(const nvram::Request & request,nvram::Response * response)70 void TestingNvramImplementation::Execute(const nvram::Request& request,
71 nvram::Response* response) {
72 if (!SendRequest(request, response)) {
73 response->result = NV_RESULT_INTERNAL_ERROR;
74 }
75 }
76
Connect()77 bool TestingNvramImplementation::Connect() {
78 if (nvram_socket_fd_ != -1) {
79 return true;
80 }
81
82 int rc =
83 socket_local_client(kFakeNvramControlSocketName,
84 ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_SEQPACKET);
85 if (rc < 0) {
86 PLOG(ERROR) << "Failed to connect fake NVRAM control socket";
87 return false;
88 }
89
90 nvram_socket_fd_ = rc;
91 return true;
92 }
93
SendRequest(const nvram::Request & request,nvram::Response * response)94 bool TestingNvramImplementation::SendRequest(const nvram::Request& request,
95 nvram::Response* response) {
96 if (!Connect()) {
97 return false;
98 }
99
100 size_t request_size = sizeof(command_buffer_);
101 if (!nvram::Encode(request, command_buffer_, &request_size)) {
102 LOG(ERROR) << "Failed to encode NVRAM request.";
103 return false;
104 }
105
106 ssize_t rc = TEMP_FAILURE_RETRY(
107 write(nvram_socket_fd_, command_buffer_, request_size));
108 if (rc < 0) {
109 PLOG(ERROR) << "Failed to send request on NVRAM control socket";
110 return false;
111 }
112
113 rc = TEMP_FAILURE_RETRY(
114 read(nvram_socket_fd_, command_buffer_, sizeof(command_buffer_)));
115 if (rc < 0 || static_cast<size_t>(rc) > sizeof(command_buffer_)) {
116 PLOG(ERROR) << "Failed to read NVRAM response";
117 return false;
118 }
119
120 if (!nvram::Decode(command_buffer_, static_cast<size_t>(rc), response)) {
121 LOG(ERROR) << "Failed to decode NVRAM response.";
122 return false;
123 }
124
125 return true;
126 }
127
128 } // namespace
129
testing_nvram_open(const hw_module_t * module,const char * device_id,hw_device_t ** device_ptr)130 extern "C" int testing_nvram_open(const hw_module_t* module,
131 const char* device_id,
132 hw_device_t** device_ptr) {
133 if (strcmp(NVRAM_HARDWARE_DEVICE_ID, device_id) != 0) {
134 return -EINVAL;
135 }
136
137 nvram::NvramDeviceAdapter* adapter =
138 new nvram::NvramDeviceAdapter(module, new TestingNvramImplementation);
139 *device_ptr = adapter->as_device();
140 return 0;
141 }
142