1 //
2 // Copyright (C) 2012 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 "update_engine/common/test_utils.h"
18 
19 #include <dirent.h>
20 #include <errno.h>
21 #include <fcntl.h>
22 #include <linux/loop.h>
23 #include <linux/major.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <sys/ioctl.h>
27 #include <sys/mount.h>
28 #include <sys/stat.h>
29 #include <sys/sysmacros.h>
30 #include <sys/types.h>
31 #include <unistd.h>
32 
33 #include <set>
34 #include <string>
35 #include <vector>
36 
37 #include <base/files/file_util.h>
38 #include <base/logging.h>
39 
40 #ifdef __ANDROID__
41 #include <libdm/loop_control.h>
42 #endif
43 
44 #include "update_engine/common/error_code_utils.h"
45 #include "update_engine/common/utils.h"
46 #include "update_engine/payload_consumer/file_writer.h"
47 
48 using std::set;
49 using std::string;
50 using std::vector;
51 using namespace std::chrono_literals;
52 
53 namespace chromeos_update_engine {
54 
PrintTo(const Extent & extent,::std::ostream * os)55 void PrintTo(const Extent& extent, ::std::ostream* os) {
56   *os << "(" << extent.start_block() << ", " << extent.num_blocks() << ")";
57 }
58 
PrintTo(const ErrorCode & error_code,::std::ostream * os)59 void PrintTo(const ErrorCode& error_code, ::std::ostream* os) {
60   *os << utils::ErrorCodeToString(error_code);
61 }
62 
63 namespace test_utils {
64 
65 const uint8_t kRandomString[] = {
66     0xf2, 0xb7, 0x55, 0x92, 0xea, 0xa6, 0xc9, 0x57, 0xe0, 0xf8, 0xeb, 0x34,
67     0x93, 0xd9, 0xc4, 0x8f, 0xcb, 0x20, 0xfa, 0x37, 0x4b, 0x40, 0xcf, 0xdc,
68     0xa5, 0x08, 0x70, 0x89, 0x79, 0x35, 0xe2, 0x3d, 0x56, 0xa4, 0x75, 0x73,
69     0xa3, 0x6d, 0xd1, 0xd5, 0x26, 0xbb, 0x9c, 0x60, 0xbd, 0x2f, 0x5a, 0xfa,
70     0xb7, 0xd4, 0x3a, 0x50, 0xa7, 0x6b, 0x3e, 0xfd, 0x61, 0x2b, 0x3a, 0x31,
71     0x30, 0x13, 0x33, 0x53, 0xdb, 0xd0, 0x32, 0x71, 0x5c, 0x39, 0xed, 0xda,
72     0xb4, 0x84, 0xca, 0xbc, 0xbd, 0x78, 0x1c, 0x0c, 0xd8, 0x0b, 0x41, 0xe8,
73     0xe1, 0xe0, 0x41, 0xad, 0x03, 0x12, 0xd3, 0x3d, 0xb8, 0x75, 0x9b, 0xe6,
74     0xd9, 0x01, 0xd0, 0x87, 0xf4, 0x36, 0xfa, 0xa7, 0x0a, 0xfa, 0xc5, 0x87,
75     0x65, 0xab, 0x9a, 0x7b, 0xeb, 0x58, 0x23, 0xf0, 0xa8, 0x0a, 0xf2, 0x33,
76     0x3a, 0xe2, 0xe3, 0x35, 0x74, 0x95, 0xdd, 0x3c, 0x59, 0x5a, 0xd9, 0x52,
77     0x3a, 0x3c, 0xac, 0xe5, 0x15, 0x87, 0x6d, 0x82, 0xbc, 0xf8, 0x7d, 0xbe,
78     0xca, 0xd3, 0x2c, 0xd6, 0xec, 0x38, 0xeb, 0xe4, 0x53, 0xb0, 0x4c, 0x3f,
79     0x39, 0x29, 0xf7, 0xa4, 0x73, 0xa8, 0xcb, 0x32, 0x50, 0x05, 0x8c, 0x1c,
80     0x1c, 0xca, 0xc9, 0x76, 0x0b, 0x8f, 0x6b, 0x57, 0x1f, 0x24, 0x2b, 0xba,
81     0x82, 0xba, 0xed, 0x58, 0xd8, 0xbf, 0xec, 0x06, 0x64, 0x52, 0x6a, 0x3f,
82     0xe4, 0xad, 0xce, 0x84, 0xb4, 0x27, 0x55, 0x14, 0xe3, 0x75, 0x59, 0x73,
83     0x71, 0x51, 0xea, 0xe8, 0xcc, 0xda, 0x4f, 0x09, 0xaf, 0xa4, 0xbc, 0x0e,
84     0xa6, 0x1f, 0xe2, 0x3a, 0xf8, 0x96, 0x7d, 0x30, 0x23, 0xc5, 0x12, 0xb5,
85     0xd8, 0x73, 0x6b, 0x71, 0xab, 0xf1, 0xd7, 0x43, 0x58, 0xa7, 0xc9, 0xf0,
86     0xe4, 0x85, 0x1c, 0xd6, 0x92, 0x50, 0x2c, 0x98, 0x36, 0xfe, 0x87, 0xaf,
87     0x43, 0x8f, 0x8f, 0xf5, 0x88, 0x48, 0x18, 0x42, 0xcf, 0x42, 0xc1, 0xa8,
88     0xe8, 0x05, 0x08, 0xa1, 0x45, 0x70, 0x5b, 0x8c, 0x39, 0x28, 0xab, 0xe9,
89     0x6b, 0x51, 0xd2, 0xcb, 0x30, 0x04, 0xea, 0x7d, 0x2f, 0x6e, 0x6c, 0x3b,
90     0x5f, 0x82, 0xd9, 0x5b, 0x89, 0x37, 0x65, 0x65, 0xbe, 0x9f, 0xa3, 0x5d,
91 };
92 
Readlink(const string & path)93 string Readlink(const string& path) {
94   vector<char> buf(PATH_MAX + 1);
95   ssize_t r = readlink(path.c_str(), buf.data(), buf.size());
96   if (r < 0)
97     return "";
98   CHECK_LT(r, static_cast<ssize_t>(buf.size()));
99   return string(buf.begin(), buf.begin() + r);
100 }
101 
WriteFileVector(const string & path,const brillo::Blob & data)102 bool WriteFileVector(const string& path, const brillo::Blob& data) {
103   return utils::WriteFile(path.c_str(), data.data(), data.size());
104 }
105 
WriteFileString(const string & path,const string & data)106 bool WriteFileString(const string& path, const string& data) {
107   return utils::WriteFile(path.c_str(), data.data(), data.size());
108 }
109 
SetLoopDeviceStatus(int loop_device_fd,const std::string & filename,int loop_number,bool writable)110 bool SetLoopDeviceStatus(int loop_device_fd,
111                          const std::string& filename,
112                          int loop_number,
113                          bool writable) {
114   struct loop_info64 device_info {};
115   device_info.lo_offset = 0;
116   device_info.lo_sizelimit = 0;  // 0 means whole file.
117   device_info.lo_flags = (writable ? 0 : LO_FLAGS_READ_ONLY);
118   device_info.lo_number = loop_number;
119   strncpy(reinterpret_cast<char*>(device_info.lo_file_name),
120           base::FilePath(filename).BaseName().value().c_str(),
121           LO_NAME_SIZE - 1);
122   device_info.lo_file_name[LO_NAME_SIZE - 1] = '\0';
123   TEST_AND_RETURN_FALSE_ERRNO(
124       ioctl(loop_device_fd, LOOP_SET_STATUS64, &device_info) == 0);
125   if (writable) {
126     // Make sure loop device isn't read only.
127     int ro = 0;
128     if (ioctl(loop_device_fd, BLKROSET, &ro) != 0) {
129       PLOG(WARNING) << "Failed to mark loop device writable.";
130     }
131   }
132 
133   return true;
134 }
135 
BindToUnusedLoopDeviceLegacy(int data_fd,const string & filename,bool writable,string * out_lo_dev_name)136 bool BindToUnusedLoopDeviceLegacy(int data_fd,
137                                   const string& filename,
138                                   bool writable,
139                                   string* out_lo_dev_name) {
140   // Get the next available loop-device.
141   int control_fd =
142       HANDLE_EINTR(open("/dev/loop-control", O_RDWR | O_LARGEFILE));
143   TEST_AND_RETURN_FALSE_ERRNO(control_fd >= 0);
144   int loop_number = ioctl(control_fd, LOOP_CTL_GET_FREE);
145   IGNORE_EINTR(close(control_fd));
146   *out_lo_dev_name = "/dev/loop" + std::to_string(loop_number);
147 
148   // Double check that the loop exists and is free.
149   int loop_device_fd =
150       HANDLE_EINTR(open(out_lo_dev_name->c_str(), O_RDWR | O_LARGEFILE));
151   if (loop_device_fd == -1 && errno == ENOENT) {
152     // Workaround the case when the loop device doesn't exist.
153     TEST_AND_RETURN_FALSE_ERRNO(mknod(out_lo_dev_name->c_str(),
154                                       S_IFBLK | 0660,
155                                       makedev(LOOP_MAJOR, loop_number)) == 0);
156     loop_device_fd =
157         HANDLE_EINTR(open(out_lo_dev_name->c_str(), O_RDWR | O_LARGEFILE));
158   }
159   TEST_AND_RETURN_FALSE_ERRNO(loop_device_fd != -1);
160   ScopedFdCloser loop_device_fd_closer(&loop_device_fd);
161 
162   struct loop_info64 device_info;
163   if (ioctl(loop_device_fd, LOOP_GET_STATUS64, &device_info) != -1 ||
164       errno != ENXIO) {
165     PLOG(ERROR) << "Loop device " << out_lo_dev_name->c_str()
166                 << " already in use";
167     return false;
168   }
169 
170   // Assign the data fd to the loop device.
171   TEST_AND_RETURN_FALSE_ERRNO(ioctl(loop_device_fd, LOOP_SET_FD, data_fd) == 0);
172   return SetLoopDeviceStatus(loop_device_fd, filename, loop_number, writable);
173 }
174 
BindToUnusedLoopDevice(const string & filename,bool writable,string * out_lo_dev_name)175 bool BindToUnusedLoopDevice(const string& filename,
176                             bool writable,
177                             string* out_lo_dev_name) {
178   CHECK(out_lo_dev_name);
179   int data_fd = open(filename.c_str(),
180                      (writable ? O_RDWR : O_RDONLY) | O_LARGEFILE | O_CLOEXEC);
181   TEST_AND_RETURN_FALSE_ERRNO(data_fd >= 0);
182   ScopedFdCloser data_fd_closer(&data_fd);
183 
184 #ifdef __ANDROID__
185   // Use libdm to bind a free loop device. The library internally handles the
186   // race condition.
187   android::dm::LoopControl loop_control;
188   TEST_AND_RETURN_FALSE(loop_control.Attach(data_fd, 5s, out_lo_dev_name));
189   int loop_device_fd = open(out_lo_dev_name->c_str(), O_RDWR | O_CLOEXEC);
190   ScopedFdCloser loop_fd_closer(&loop_device_fd);
191   int loop_number;
192   TEST_AND_RETURN_FALSE(
193       sscanf(out_lo_dev_name->c_str(), "/dev/block/loop%d", &loop_number) == 1);
194   return SetLoopDeviceStatus(loop_device_fd, filename, loop_number, writable);
195 #else
196   return BindToUnusedLoopDeviceLegacy(
197       data_fd, filename, writable, out_lo_dev_name);
198 #endif
199 }
200 
UnbindLoopDevice(const string & lo_dev_name)201 bool UnbindLoopDevice(const string& lo_dev_name) {
202   int loop_device_fd =
203       HANDLE_EINTR(open(lo_dev_name.c_str(), O_RDWR | O_LARGEFILE));
204   if (loop_device_fd == -1 && errno == ENOENT)
205     return true;
206   TEST_AND_RETURN_FALSE_ERRNO(loop_device_fd != -1);
207   ScopedFdCloser loop_device_fd_closer(&loop_device_fd);
208 
209   struct loop_info64 device_info;
210   // Check if the device is bound before trying to unbind it.
211   int get_stat_err = ioctl(loop_device_fd, LOOP_GET_STATUS64, &device_info);
212   if (get_stat_err == -1 && errno == ENXIO)
213     return true;
214 
215   TEST_AND_RETURN_FALSE_ERRNO(ioctl(loop_device_fd, LOOP_CLR_FD) == 0);
216   return true;
217 }
218 
ExpectVectorsEq(const brillo::Blob & expected,const brillo::Blob & actual)219 bool ExpectVectorsEq(const brillo::Blob& expected, const brillo::Blob& actual) {
220   EXPECT_EQ(expected.size(), actual.size());
221   if (expected.size() != actual.size())
222     return false;
223   bool is_all_eq = true;
224   for (unsigned int i = 0; i < expected.size(); i++) {
225     EXPECT_EQ(expected[i], actual[i]) << "offset: " << i;
226     is_all_eq = is_all_eq && (expected[i] == actual[i]);
227   }
228   return is_all_eq;
229 }
230 
FillWithData(brillo::Blob * buffer)231 void FillWithData(brillo::Blob* buffer) {
232   size_t input_counter = 0;
233   for (uint8_t& b : *buffer) {
234     b = kRandomString[input_counter];
235     input_counter++;
236     input_counter %= sizeof(kRandomString);
237   }
238 }
239 
ScopedLoopMounter(const string & file_path,string * mnt_path,unsigned long flags)240 ScopedLoopMounter::ScopedLoopMounter(const string& file_path,
241                                      string* mnt_path,
242                                      unsigned long flags) {  // NOLINT - long
243   EXPECT_TRUE(temp_dir_.CreateUniqueTempDir());
244   *mnt_path = temp_dir_.GetPath().value();
245 
246   string loop_dev;
247   loop_binder_.reset(
248       new ScopedLoopbackDeviceBinder(file_path, true, &loop_dev));
249 
250   EXPECT_TRUE(utils::MountFilesystem(loop_dev, *mnt_path, flags, "", ""));
251   unmounter_.reset(new ScopedFilesystemUnmounter(*mnt_path));
252 }
253 
GetBuildArtifactsPath()254 base::FilePath GetBuildArtifactsPath() {
255   base::FilePath exe_path;
256   base::ReadSymbolicLink(base::FilePath("/proc/self/exe"), &exe_path);
257   return exe_path.DirName();
258 }
259 
GetBuildArtifactsPath(const string & relative_path)260 string GetBuildArtifactsPath(const string& relative_path) {
261   return GetBuildArtifactsPath().Append(relative_path).value();
262 }
263 
264 }  // namespace test_utils
265 }  // namespace chromeos_update_engine
266