1 /*
2 * Copyright (C) 2024 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 <memory>
18 #include <sys/sendfile.h>
19 #include <dirent.h>
20 #include <stdio.h>
21 #include <openssl/sha.h>
22 #include <fstream>
23 #include <sstream>
24
25 #include <android-base/file.h>
26 #include <android-base/logging.h>
27 #include <android-base/unique_fd.h>
28
29 #include <aconfigd.pb.h>
30 #include "aconfigd_util.h"
31
32 using namespace android::base;
33
34 namespace android {
35 namespace aconfigd {
36
37 /// Remove all files in a dir
RemoveFilesInDir(const std::string & dir)38 Result<void> RemoveFilesInDir(const std::string& dir) {
39 auto dir_ptr = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(dir.c_str()), closedir);
40 if (!dir_ptr) {
41 return ErrnoError() << "failed to open dir " << dir;
42 }
43
44 struct dirent* entry;
45 while ((entry = readdir(dir_ptr.get())) != nullptr) {
46 if (entry->d_type != DT_REG) {
47 continue;
48 }
49 auto file = dir + "/" + entry->d_name;
50 if (unlink(file.c_str()) == -1) {
51 return ErrnoError() << "unlink() failed for " << file;
52 }
53 }
54
55 return {};
56 }
57
58 /// Copy file
CopyFile(const std::string & src,const std::string & dst,mode_t mode)59 Result<void> CopyFile(const std::string& src, const std::string& dst, mode_t mode) {
60 android::base::unique_fd src_fd(
61 TEMP_FAILURE_RETRY(open(src.c_str(), O_RDONLY | O_NOFOLLOW | O_CLOEXEC)));
62 if (src_fd == -1) {
63 return ErrnoError() << "open() failed for " << src;
64 }
65
66 if (FileExists(dst.c_str())) {
67 if (chmod(dst.c_str(), 0644) == -1) {
68 return ErrnoError() << "chmod() failed for " << dst;
69 }
70 }
71
72 android::base::unique_fd dst_fd(TEMP_FAILURE_RETRY(
73 open(dst.c_str(), O_WRONLY | O_CREAT | O_NOFOLLOW | O_TRUNC | O_CLOEXEC, 0644)));
74 if (dst_fd == -1) {
75 return ErrnoError() << "open() failed for " << dst;
76 }
77
78 struct stat st;
79 if (fstat(src_fd.get(), &st) == -1) {
80 return ErrnoError() << "fstat() failed";
81 }
82 auto len = st.st_size;
83
84 if (sendfile(dst_fd, src_fd, nullptr, len) == -1) {
85 return ErrnoError() << "sendfile() failed";
86 }
87
88 if (chmod(dst.c_str(), mode) == -1) {
89 return ErrnoError() << "chmod() failed";
90 }
91
92 return {};
93 }
94
95 /// Get a file's timestamp in nano second
GetFileTimeStamp(const std::string & file)96 Result<uint64_t> GetFileTimeStamp(const std::string& file) {
97 struct stat st;
98 int result = stat(file.c_str(), &st);
99 if (result == -1) {
100 return ErrnoError() << "stat() failed";
101 }
102 uint64_t timestamp = st.st_mtim.tv_sec*1000000000 + st.st_mtim.tv_nsec;
103 return timestamp;
104 }
105
FileExists(const std::string & file)106 bool FileExists(const std::string& file) {
107 struct stat st;
108 return stat(file.c_str(), &st) == 0 ? true : false;
109 }
110
FileNonZeroSize(const std::string & file)111 bool FileNonZeroSize(const std::string& file) {
112 struct stat st;
113 return stat(file.c_str(), &st) == 0 ? st.st_size > 0 : false;
114 }
115
GetFilesDigest(const std::vector<std::string> & files)116 Result<std::string> GetFilesDigest(const std::vector<std::string>& files) {
117 SHA512_CTX ctx;
118 SHA512_Init(&ctx);
119
120 for (const auto& file : files) {
121 std::ifstream stream(file, std::ios::binary);
122 if (stream.bad()) {
123 return Error() << "Failed to open " << file;
124 }
125
126 char buf[1024];
127 while (!stream.eof()) {
128 stream.read(buf, 1024);
129 if (stream.bad()) {
130 return Error() << "Failed to read " << file;
131 }
132 int bytes_read = stream.gcount();
133 SHA512_Update(&ctx, buf, bytes_read);
134 }
135 }
136
137 uint8_t hash[SHA512_DIGEST_LENGTH];
138 SHA512_Final(hash, &ctx);
139 std::stringstream ss;
140 ss << std::hex;
141 for (int i = 0; i < SHA512_DIGEST_LENGTH; i++) {
142 ss << std::setw(2) << std::setfill('0') << static_cast<int>(hash[i]);
143 }
144 return ss.str();
145 }
146
147 /// convert override type enum to string
OverrideTypeToStr(const StorageRequestMessage::FlagOverrideType & override_type)148 std::string OverrideTypeToStr(
149 const StorageRequestMessage::FlagOverrideType& override_type) {
150 switch (override_type) {
151 case StorageRequestMessage::LOCAL_IMMEDIATE: {
152 return "local immediate";
153 }
154 case StorageRequestMessage::LOCAL_ON_REBOOT: {
155 return "local on reboot";
156 }
157 case StorageRequestMessage::SERVER_ON_REBOOT: {
158 return "server on reboot";
159 }
160 default: {
161 return "unknown";
162 }
163 }
164 }
165
166 } // namespace aconfig
167 } // namespace android
168