1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
/*
* Copyright (C) 2020 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <arpa/inet.h>
#include <cutils/sockets.h>
#include <errno.h>
#include <netdb.h>
#include <netinet/in.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#include <chrono>
#include <sstream>
#include <android-base/logging.h>
#include <android-base/parseint.h>
#include <android-base/properties.h>
#include <android-base/strings.h>
#include <libsnapshot/snapuserd_client.h>
namespace android {
namespace snapshot {
using namespace std::chrono_literals;
using android::base::unique_fd;
bool EnsureSnapuserdStarted() {
if (android::base::GetProperty("init.svc.snapuserd", "") == "running") {
return true;
}
android::base::SetProperty("ctl.start", "snapuserd");
if (!android::base::WaitForProperty("init.svc.snapuserd", "running", 10s)) {
LOG(ERROR) << "Timed out waiting for snapuserd to start.";
return false;
}
return true;
}
SnapuserdClient::SnapuserdClient(android::base::unique_fd&& sockfd) : sockfd_(std::move(sockfd)) {}
static inline bool IsRetryErrno() {
return errno == ECONNREFUSED || errno == EINTR || errno == ENOENT;
}
std::unique_ptr<SnapuserdClient> SnapuserdClient::Connect(const std::string& socket_name,
std::chrono::milliseconds timeout_ms) {
unique_fd fd;
auto start = std::chrono::steady_clock::now();
while (true) {
fd.reset(socket_local_client(socket_name.c_str(), ANDROID_SOCKET_NAMESPACE_RESERVED,
SOCK_STREAM));
if (fd >= 0) break;
if (fd < 0 && !IsRetryErrno()) {
PLOG(ERROR) << "connect failed: " << socket_name;
return nullptr;
}
auto now = std::chrono::steady_clock::now();
auto elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(now - start);
if (elapsed >= timeout_ms) {
LOG(ERROR) << "Timed out connecting to snapuserd socket: " << socket_name;
return nullptr;
}
std::this_thread::sleep_for(100ms);
}
auto client = std::make_unique<SnapuserdClient>(std::move(fd));
if (!client->ValidateConnection()) {
return nullptr;
}
return client;
}
bool SnapuserdClient::ValidateConnection() {
if (!Sendmsg("query")) {
return false;
}
std::string str = Receivemsg();
// If the daemon is passive then fallback to secondary active daemon. Daemon
// is passive during transition phase.
if (str.find("passive") != std::string::npos) {
LOG(ERROR) << "Snapuserd is terminating";
return false;
}
if (str != "active") {
LOG(ERROR) << "Received failure querying daemon";
return false;
}
return true;
}
bool SnapuserdClient::Sendmsg(const std::string& msg) {
LOG(DEBUG) << "Sendmsg: msg " << msg << " sockfd: " << sockfd_;
ssize_t numBytesSent = TEMP_FAILURE_RETRY(send(sockfd_, msg.data(), msg.size(), MSG_NOSIGNAL));
if (numBytesSent < 0) {
PLOG(ERROR) << "Send failed";
return false;
}
if ((size_t)numBytesSent < msg.size()) {
LOG(ERROR) << "Partial data sent, expected " << msg.size() << " bytes, sent "
<< numBytesSent;
return false;
}
return true;
}
bool SnapuserdClient::WaitForDeviceDelete(const std::string& control_device) {
std::string msg = "delete," + control_device;
if (!Sendmsg(msg)) {
LOG(ERROR) << "Failed to send message " << msg << " to snapuserd";
return false;
}
std::string response = Receivemsg();
if (response != "success") {
LOG(ERROR) << "Failed waiting to delete device " << control_device;
return false;
}
return true;
}
std::string SnapuserdClient::Receivemsg() {
char msg[PACKET_SIZE];
ssize_t ret = TEMP_FAILURE_RETRY(recv(sockfd_, msg, sizeof(msg), 0));
if (ret < 0) {
PLOG(ERROR) << "Snapuserd:client: recv failed";
return {};
}
if (ret == 0) {
LOG(DEBUG) << "Snapuserd:client disconnected";
return {};
}
return std::string(msg, ret);
}
bool SnapuserdClient::StopSnapuserd() {
if (!Sendmsg("stop")) {
LOG(ERROR) << "Failed to send stop message to snapuserd daemon";
return false;
}
sockfd_ = {};
return true;
}
bool SnapuserdClient::AttachDmUser(const std::string& misc_name) {
std::string msg = "start," + misc_name;
if (!Sendmsg(msg)) {
LOG(ERROR) << "Failed to send message " << msg << " to snapuserd daemon";
return false;
}
std::string str = Receivemsg();
if (str != "success") {
LOG(ERROR) << "Failed to receive ack for " << msg << " from snapuserd daemon";
return false;
}
LOG(DEBUG) << "Snapuserd daemon initialized with " << msg;
return true;
}
uint64_t SnapuserdClient::InitDmUserCow(const std::string& misc_name, const std::string& cow_device,
const std::string& backing_device) {
std::vector<std::string> parts = {"init", misc_name, cow_device, backing_device};
std::string msg = android::base::Join(parts, ",");
if (!Sendmsg(msg)) {
LOG(ERROR) << "Failed to send message " << msg << " to snapuserd daemon";
return 0;
}
std::string str = Receivemsg();
std::vector<std::string> input = android::base::Split(str, ",");
if (input.empty() || input[0] != "success") {
LOG(ERROR) << "Failed to receive number of sectors for " << msg << " from snapuserd daemon";
return 0;
}
LOG(DEBUG) << "Snapuserd daemon COW device initialized: " << cow_device
<< " Num-sectors: " << input[1];
uint64_t num_sectors = 0;
if (!android::base::ParseUint(input[1], &num_sectors)) {
LOG(ERROR) << "Failed to parse input string to sectors";
return 0;
}
return num_sectors;
}
bool SnapuserdClient::DetachSnapuserd() {
if (!Sendmsg("detach")) {
LOG(ERROR) << "Failed to detach snapuserd.";
return false;
}
return true;
}
} // namespace snapshot
} // namespace android
|
