1 /*
2 * Copyright (C) 2008 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 "zip_archive.h"
18
19 #include <fcntl.h>
20 #include <stdio.h>
21 #include <sys/mman.h> // For the PROT_* and MAP_* constants.
22 #include <sys/stat.h>
23 #include <sys/types.h>
24 #include <unistd.h>
25 #include <vector>
26
27 #include "android-base/stringprintf.h"
28 #include "base/unix_file/fd_file.h"
29
30 namespace art {
31
32 // Log file contents and mmap info when mapping entries directly.
33 static constexpr const bool kDebugZipMapDirectly = false;
34
35 using android::base::StringPrintf;
36
GetUncompressedLength()37 uint32_t ZipEntry::GetUncompressedLength() {
38 return zip_entry_->uncompressed_length;
39 }
40
GetCrc32()41 uint32_t ZipEntry::GetCrc32() {
42 return zip_entry_->crc32;
43 }
44
IsUncompressed()45 bool ZipEntry::IsUncompressed() {
46 return zip_entry_->method == kCompressStored;
47 }
48
IsAlignedTo(size_t alignment)49 bool ZipEntry::IsAlignedTo(size_t alignment) {
50 DCHECK(IsPowerOfTwo(alignment)) << alignment;
51 return IsAlignedParam(zip_entry_->offset, static_cast<int>(alignment));
52 }
53
~ZipEntry()54 ZipEntry::~ZipEntry() {
55 delete zip_entry_;
56 }
57
ExtractToFile(File & file,std::string * error_msg)58 bool ZipEntry::ExtractToFile(File& file, std::string* error_msg) {
59 const int32_t error = ExtractEntryToFile(handle_, zip_entry_, file.Fd());
60 if (error) {
61 *error_msg = std::string(ErrorCodeString(error));
62 return false;
63 }
64
65 return true;
66 }
67
ExtractToMemMap(const char * zip_filename,const char * entry_filename,std::string * error_msg)68 MemMap* ZipEntry::ExtractToMemMap(const char* zip_filename, const char* entry_filename,
69 std::string* error_msg) {
70 std::string name(entry_filename);
71 name += " extracted in memory from ";
72 name += zip_filename;
73 std::unique_ptr<MemMap> map(MemMap::MapAnonymous(name.c_str(),
74 nullptr, GetUncompressedLength(),
75 PROT_READ | PROT_WRITE, false, false,
76 error_msg));
77 if (map.get() == nullptr) {
78 DCHECK(!error_msg->empty());
79 return nullptr;
80 }
81
82 const int32_t error = ExtractToMemory(handle_, zip_entry_,
83 map->Begin(), map->Size());
84 if (error) {
85 *error_msg = std::string(ErrorCodeString(error));
86 return nullptr;
87 }
88
89 return map.release();
90 }
91
MapDirectlyFromFile(const char * zip_filename,std::string * error_msg)92 MemMap* ZipEntry::MapDirectlyFromFile(const char* zip_filename, std::string* error_msg) {
93 const int zip_fd = GetFileDescriptor(handle_);
94 const char* entry_filename = entry_name_.c_str();
95
96 // Should not happen since we don't have a memory ZipArchive constructor.
97 // However the underlying ZipArchive isn't required to have an FD,
98 // so check to be sure.
99 CHECK_GE(zip_fd, 0) <<
100 StringPrintf("Cannot map '%s' (in zip '%s') directly because the zip archive "
101 "is not file backed.",
102 entry_filename,
103 zip_filename);
104
105 if (!IsUncompressed()) {
106 *error_msg = StringPrintf("Cannot map '%s' (in zip '%s') directly because it is compressed.",
107 entry_filename,
108 zip_filename);
109 return nullptr;
110 } else if (zip_entry_->uncompressed_length != zip_entry_->compressed_length) {
111 *error_msg = StringPrintf("Cannot map '%s' (in zip '%s') directly because "
112 "entry has bad size (%u != %u).",
113 entry_filename,
114 zip_filename,
115 zip_entry_->uncompressed_length,
116 zip_entry_->compressed_length);
117 return nullptr;
118 }
119
120 std::string name(entry_filename);
121 name += " mapped directly in memory from ";
122 name += zip_filename;
123
124 const off_t offset = zip_entry_->offset;
125
126 if (kDebugZipMapDirectly) {
127 LOG(INFO) << "zip_archive: " << "make mmap of " << name << " @ offset = " << offset;
128 }
129
130 std::unique_ptr<MemMap> map(
131 MemMap::MapFileAtAddress(nullptr, // Expected pointer address
132 GetUncompressedLength(), // Byte count
133 PROT_READ | PROT_WRITE,
134 MAP_PRIVATE,
135 zip_fd,
136 offset,
137 false, // Don't restrict allocation to lower4GB
138 false, // Doesn't overlap existing map (reuse=false)
139 name.c_str(),
140 /*out*/error_msg));
141
142 if (map == nullptr) {
143 DCHECK(!error_msg->empty());
144 }
145
146 if (kDebugZipMapDirectly) {
147 // Dump contents of file, same format as using this shell command:
148 // $> od -j <offset> -t x1 <zip_filename>
149 static constexpr const int kMaxDumpChars = 15;
150 lseek(zip_fd, 0, SEEK_SET);
151
152 int count = offset + kMaxDumpChars;
153
154 std::string tmp;
155 char buf;
156
157 // Dump file contents.
158 int i = 0;
159 while (read(zip_fd, &buf, 1) > 0 && i < count) {
160 tmp += StringPrintf("%3d ", (unsigned int)buf);
161 ++i;
162 }
163
164 LOG(INFO) << "map_fd raw bytes starting at 0";
165 LOG(INFO) << "" << tmp;
166 LOG(INFO) << "---------------------------";
167
168 // Dump map contents.
169 if (map != nullptr) {
170 tmp = "";
171
172 count = kMaxDumpChars;
173
174 uint8_t* begin = map->Begin();
175 for (i = 0; i < count; ++i) {
176 tmp += StringPrintf("%3d ", (unsigned int)begin[i]);
177 }
178
179 LOG(INFO) << "map address " << StringPrintf("%p", begin);
180 LOG(INFO) << "map first " << kMaxDumpChars << " chars:";
181 LOG(INFO) << tmp;
182 }
183 }
184
185 return map.release();
186 }
187
SetCloseOnExec(int fd)188 static void SetCloseOnExec(int fd) {
189 // This dance is more portable than Linux's O_CLOEXEC open(2) flag.
190 int flags = fcntl(fd, F_GETFD);
191 if (flags == -1) {
192 PLOG(WARNING) << "fcntl(" << fd << ", F_GETFD) failed";
193 return;
194 }
195 int rc = fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
196 if (rc == -1) {
197 PLOG(WARNING) << "fcntl(" << fd << ", F_SETFD, " << flags << ") failed";
198 return;
199 }
200 }
201
Open(const char * filename,std::string * error_msg)202 ZipArchive* ZipArchive::Open(const char* filename, std::string* error_msg) {
203 DCHECK(filename != nullptr);
204
205 ZipArchiveHandle handle;
206 const int32_t error = OpenArchive(filename, &handle);
207 if (error) {
208 *error_msg = std::string(ErrorCodeString(error));
209 CloseArchive(handle);
210 return nullptr;
211 }
212
213 SetCloseOnExec(GetFileDescriptor(handle));
214 return new ZipArchive(handle);
215 }
216
OpenFromFd(int fd,const char * filename,std::string * error_msg)217 ZipArchive* ZipArchive::OpenFromFd(int fd, const char* filename, std::string* error_msg) {
218 DCHECK(filename != nullptr);
219 DCHECK_GT(fd, 0);
220
221 ZipArchiveHandle handle;
222 const int32_t error = OpenArchiveFd(fd, filename, &handle);
223 if (error) {
224 *error_msg = std::string(ErrorCodeString(error));
225 CloseArchive(handle);
226 return nullptr;
227 }
228
229 SetCloseOnExec(GetFileDescriptor(handle));
230 return new ZipArchive(handle);
231 }
232
Find(const char * name,std::string * error_msg) const233 ZipEntry* ZipArchive::Find(const char* name, std::string* error_msg) const {
234 DCHECK(name != nullptr);
235
236 // Resist the urge to delete the space. <: is a bigraph sequence.
237 std::unique_ptr< ::ZipEntry> zip_entry(new ::ZipEntry);
238 const int32_t error = FindEntry(handle_, ZipString(name), zip_entry.get());
239 if (error) {
240 *error_msg = std::string(ErrorCodeString(error));
241 return nullptr;
242 }
243
244 return new ZipEntry(handle_, zip_entry.release(), name);
245 }
246
~ZipArchive()247 ZipArchive::~ZipArchive() {
248 CloseArchive(handle_);
249 }
250
251 } // namespace art
252