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 "ziparchive/zip_archive.h"
29
30 #include "base/bit_utils.h"
31 #include "base/unix_file/fd_file.h"
32
33 namespace art {
34
35 // Log file contents and mmap info when mapping entries directly.
36 static constexpr const bool kDebugZipMapDirectly = false;
37
38 using android::base::StringPrintf;
39
GetUncompressedLength()40 uint32_t ZipEntry::GetUncompressedLength() {
41 return zip_entry_->uncompressed_length;
42 }
43
GetCrc32()44 uint32_t ZipEntry::GetCrc32() {
45 return zip_entry_->crc32;
46 }
47
IsUncompressed()48 bool ZipEntry::IsUncompressed() {
49 return zip_entry_->method == kCompressStored;
50 }
51
IsAlignedTo(size_t alignment)52 bool ZipEntry::IsAlignedTo(size_t alignment) {
53 DCHECK(IsPowerOfTwo(alignment)) << alignment;
54 return IsAlignedParam(zip_entry_->offset, static_cast<int>(alignment));
55 }
56
~ZipEntry()57 ZipEntry::~ZipEntry() {
58 delete zip_entry_;
59 }
60
ExtractToFile(File & file,std::string * error_msg)61 bool ZipEntry::ExtractToFile(File& file, std::string* error_msg) {
62 const int32_t error = ExtractEntryToFile(handle_, zip_entry_, file.Fd());
63 if (error) {
64 *error_msg = std::string(ErrorCodeString(error));
65 return false;
66 }
67
68 return true;
69 }
70
ExtractToMemMap(const char * zip_filename,const char * entry_filename,std::string * error_msg)71 MemMap* ZipEntry::ExtractToMemMap(const char* zip_filename, const char* entry_filename,
72 std::string* error_msg) {
73 std::string name(entry_filename);
74 name += " extracted in memory from ";
75 name += zip_filename;
76 std::unique_ptr<MemMap> map(MemMap::MapAnonymous(name.c_str(),
77 nullptr, GetUncompressedLength(),
78 PROT_READ | PROT_WRITE, false, false,
79 error_msg));
80 if (map.get() == nullptr) {
81 DCHECK(!error_msg->empty());
82 return nullptr;
83 }
84
85 const int32_t error = ExtractToMemory(handle_, zip_entry_,
86 map->Begin(), map->Size());
87 if (error) {
88 *error_msg = std::string(ErrorCodeString(error));
89 return nullptr;
90 }
91
92 return map.release();
93 }
94
MapDirectlyFromFile(const char * zip_filename,std::string * error_msg)95 MemMap* ZipEntry::MapDirectlyFromFile(const char* zip_filename, std::string* error_msg) {
96 const int zip_fd = GetFileDescriptor(handle_);
97 const char* entry_filename = entry_name_.c_str();
98
99 // Should not happen since we don't have a memory ZipArchive constructor.
100 // However the underlying ZipArchive isn't required to have an FD,
101 // so check to be sure.
102 CHECK_GE(zip_fd, 0) <<
103 StringPrintf("Cannot map '%s' (in zip '%s') directly because the zip archive "
104 "is not file backed.",
105 entry_filename,
106 zip_filename);
107
108 if (!IsUncompressed()) {
109 *error_msg = StringPrintf("Cannot map '%s' (in zip '%s') directly because it is compressed.",
110 entry_filename,
111 zip_filename);
112 return nullptr;
113 } else if (zip_entry_->uncompressed_length != zip_entry_->compressed_length) {
114 *error_msg = StringPrintf("Cannot map '%s' (in zip '%s') directly because "
115 "entry has bad size (%u != %u).",
116 entry_filename,
117 zip_filename,
118 zip_entry_->uncompressed_length,
119 zip_entry_->compressed_length);
120 return nullptr;
121 }
122
123 std::string name(entry_filename);
124 name += " mapped directly in memory from ";
125 name += zip_filename;
126
127 const off_t offset = zip_entry_->offset;
128
129 if (kDebugZipMapDirectly) {
130 LOG(INFO) << "zip_archive: " << "make mmap of " << name << " @ offset = " << offset;
131 }
132
133 std::unique_ptr<MemMap> map(
134 MemMap::MapFileAtAddress(nullptr, // Expected pointer address
135 GetUncompressedLength(), // Byte count
136 PROT_READ | PROT_WRITE,
137 MAP_PRIVATE,
138 zip_fd,
139 offset,
140 false, // Don't restrict allocation to lower4GB
141 false, // Doesn't overlap existing map (reuse=false)
142 name.c_str(),
143 /*out*/error_msg));
144
145 if (map == nullptr) {
146 DCHECK(!error_msg->empty());
147 }
148
149 if (kDebugZipMapDirectly) {
150 // Dump contents of file, same format as using this shell command:
151 // $> od -j <offset> -t x1 <zip_filename>
152 static constexpr const int kMaxDumpChars = 15;
153 lseek(zip_fd, 0, SEEK_SET);
154
155 int count = offset + kMaxDumpChars;
156
157 std::string tmp;
158 char buf;
159
160 // Dump file contents.
161 int i = 0;
162 while (read(zip_fd, &buf, 1) > 0 && i < count) {
163 tmp += StringPrintf("%3d ", (unsigned int)buf);
164 ++i;
165 }
166
167 LOG(INFO) << "map_fd raw bytes starting at 0";
168 LOG(INFO) << "" << tmp;
169 LOG(INFO) << "---------------------------";
170
171 // Dump map contents.
172 if (map != nullptr) {
173 tmp = "";
174
175 count = kMaxDumpChars;
176
177 uint8_t* begin = map->Begin();
178 for (i = 0; i < count; ++i) {
179 tmp += StringPrintf("%3d ", (unsigned int)begin[i]);
180 }
181
182 LOG(INFO) << "map address " << StringPrintf("%p", begin);
183 LOG(INFO) << "map first " << kMaxDumpChars << " chars:";
184 LOG(INFO) << tmp;
185 }
186 }
187
188 return map.release();
189 }
190
SetCloseOnExec(int fd)191 static void SetCloseOnExec(int fd) {
192 // This dance is more portable than Linux's O_CLOEXEC open(2) flag.
193 int flags = fcntl(fd, F_GETFD);
194 if (flags == -1) {
195 PLOG(WARNING) << "fcntl(" << fd << ", F_GETFD) failed";
196 return;
197 }
198 int rc = fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
199 if (rc == -1) {
200 PLOG(WARNING) << "fcntl(" << fd << ", F_SETFD, " << flags << ") failed";
201 return;
202 }
203 }
204
Open(const char * filename,std::string * error_msg)205 ZipArchive* ZipArchive::Open(const char* filename, std::string* error_msg) {
206 DCHECK(filename != nullptr);
207
208 ZipArchiveHandle handle;
209 const int32_t error = OpenArchive(filename, &handle);
210 if (error) {
211 *error_msg = std::string(ErrorCodeString(error));
212 CloseArchive(handle);
213 return nullptr;
214 }
215
216 SetCloseOnExec(GetFileDescriptor(handle));
217 return new ZipArchive(handle);
218 }
219
OpenFromFd(int fd,const char * filename,std::string * error_msg)220 ZipArchive* ZipArchive::OpenFromFd(int fd, const char* filename, std::string* error_msg) {
221 DCHECK(filename != nullptr);
222 DCHECK_GT(fd, 0);
223
224 ZipArchiveHandle handle;
225 const int32_t error = OpenArchiveFd(fd, filename, &handle);
226 if (error) {
227 *error_msg = std::string(ErrorCodeString(error));
228 CloseArchive(handle);
229 return nullptr;
230 }
231
232 SetCloseOnExec(GetFileDescriptor(handle));
233 return new ZipArchive(handle);
234 }
235
Find(const char * name,std::string * error_msg) const236 ZipEntry* ZipArchive::Find(const char* name, std::string* error_msg) const {
237 DCHECK(name != nullptr);
238
239 // Resist the urge to delete the space. <: is a bigraph sequence.
240 std::unique_ptr< ::ZipEntry> zip_entry(new ::ZipEntry);
241 const int32_t error = FindEntry(handle_, ZipString(name), zip_entry.get());
242 if (error) {
243 *error_msg = std::string(ErrorCodeString(error));
244 return nullptr;
245 }
246
247 return new ZipEntry(handle_, zip_entry.release(), name);
248 }
249
~ZipArchive()250 ZipArchive::~ZipArchive() {
251 CloseArchive(handle_);
252 }
253
254 } // namespace art
255