1/*
2 * Copyright (C) 2007 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//
18// Read-only access to Zip archives, with minimal heap allocation.
19//
20#define LOG_TAG "zipro"
21//#define LOG_NDEBUG 0
22#include <androidfw/ZipFileRO.h>
23#include <utils/Log.h>
24#include <utils/Compat.h>
25#include <utils/misc.h>
26#include <utils/threads.h>
27#include <ziparchive/zip_archive.h>
28
29#include <zlib.h>
30
31#include <string.h>
32#include <fcntl.h>
33#include <errno.h>
34#include <assert.h>
35#include <unistd.h>
36
37using namespace android;
38
39class _ZipEntryRO {
40public:
41    ZipEntry entry;
42    ZipString name;
43    void *cookie;
44
45    _ZipEntryRO() : cookie(NULL) {}
46
47    ~_ZipEntryRO() {
48      EndIteration(cookie);
49    }
50
51private:
52    _ZipEntryRO(const _ZipEntryRO& other);
53    _ZipEntryRO& operator=(const _ZipEntryRO& other);
54};
55
56ZipFileRO::~ZipFileRO() {
57    CloseArchive(mHandle);
58    free(mFileName);
59}
60
61/*
62 * Open the specified file read-only.  We memory-map the entire thing and
63 * close the file before returning.
64 */
65/* static */ ZipFileRO* ZipFileRO::open(const char* zipFileName)
66{
67    ZipArchiveHandle handle;
68    const int32_t error = OpenArchive(zipFileName, &handle);
69    if (error) {
70        ALOGW("Error opening archive %s: %s", zipFileName, ErrorCodeString(error));
71        CloseArchive(handle);
72        return NULL;
73    }
74
75    return new ZipFileRO(handle, strdup(zipFileName));
76}
77
78
79ZipEntryRO ZipFileRO::findEntryByName(const char* entryName) const
80{
81    _ZipEntryRO* data = new _ZipEntryRO;
82
83    data->name = ZipString(entryName);
84
85    const int32_t error = FindEntry(mHandle, data->name, &(data->entry));
86    if (error) {
87        delete data;
88        return NULL;
89    }
90
91    return (ZipEntryRO) data;
92}
93
94/*
95 * Get the useful fields from the zip entry.
96 *
97 * Returns "false" if the offsets to the fields or the contents of the fields
98 * appear to be bogus.
99 */
100bool ZipFileRO::getEntryInfo(ZipEntryRO entry, uint16_t* pMethod,
101    uint32_t* pUncompLen, uint32_t* pCompLen, off64_t* pOffset,
102    uint32_t* pModWhen, uint32_t* pCrc32) const
103{
104    const _ZipEntryRO* zipEntry = reinterpret_cast<_ZipEntryRO*>(entry);
105    const ZipEntry& ze = zipEntry->entry;
106
107    if (pMethod != NULL) {
108        *pMethod = ze.method;
109    }
110    if (pUncompLen != NULL) {
111        *pUncompLen = ze.uncompressed_length;
112    }
113    if (pCompLen != NULL) {
114        *pCompLen = ze.compressed_length;
115    }
116    if (pOffset != NULL) {
117        *pOffset = ze.offset;
118    }
119    if (pModWhen != NULL) {
120        *pModWhen = ze.mod_time;
121    }
122    if (pCrc32 != NULL) {
123        *pCrc32 = ze.crc32;
124    }
125
126    return true;
127}
128
129bool ZipFileRO::startIteration(void** cookie) {
130  return startIteration(cookie, NULL, NULL);
131}
132
133bool ZipFileRO::startIteration(void** cookie, const char* prefix, const char* suffix)
134{
135    _ZipEntryRO* ze = new _ZipEntryRO;
136    ZipString pe(prefix ? prefix : "");
137    ZipString se(suffix ? suffix : "");
138    int32_t error = StartIteration(mHandle, &(ze->cookie),
139                                   prefix ? &pe : NULL,
140                                   suffix ? &se : NULL);
141    if (error) {
142        ALOGW("Could not start iteration over %s: %s", mFileName, ErrorCodeString(error));
143        delete ze;
144        return false;
145    }
146
147    *cookie = ze;
148    return true;
149}
150
151ZipEntryRO ZipFileRO::nextEntry(void* cookie)
152{
153    _ZipEntryRO* ze = reinterpret_cast<_ZipEntryRO*>(cookie);
154    int32_t error = Next(ze->cookie, &(ze->entry), &(ze->name));
155    if (error) {
156        if (error != -1) {
157            ALOGW("Error iteration over %s: %s", mFileName, ErrorCodeString(error));
158        }
159        return NULL;
160    }
161
162    return &(ze->entry);
163}
164
165void ZipFileRO::endIteration(void* cookie)
166{
167    delete reinterpret_cast<_ZipEntryRO*>(cookie);
168}
169
170void ZipFileRO::releaseEntry(ZipEntryRO entry) const
171{
172    delete reinterpret_cast<_ZipEntryRO*>(entry);
173}
174
175/*
176 * Copy the entry's filename to the buffer.
177 */
178int ZipFileRO::getEntryFileName(ZipEntryRO entry, char* buffer, size_t bufLen)
179    const
180{
181    const _ZipEntryRO* zipEntry = reinterpret_cast<_ZipEntryRO*>(entry);
182    const uint16_t requiredSize = zipEntry->name.name_length + 1;
183
184    if (bufLen < requiredSize) {
185        ALOGW("Buffer too short, requires %d bytes for entry name", requiredSize);
186        return requiredSize;
187    }
188
189    memcpy(buffer, zipEntry->name.name, requiredSize - 1);
190    buffer[requiredSize - 1] = '\0';
191
192    return 0;
193}
194
195/*
196 * Create a new FileMap object that spans the data in "entry".
197 */
198FileMap* ZipFileRO::createEntryFileMap(ZipEntryRO entry) const
199{
200    const _ZipEntryRO *zipEntry = reinterpret_cast<_ZipEntryRO*>(entry);
201    const ZipEntry& ze = zipEntry->entry;
202    int fd = GetFileDescriptor(mHandle);
203    size_t actualLen = 0;
204
205    if (ze.method == kCompressStored) {
206        actualLen = ze.uncompressed_length;
207    } else {
208        actualLen = ze.compressed_length;
209    }
210
211    FileMap* newMap = new FileMap();
212    if (!newMap->create(mFileName, fd, ze.offset, actualLen, true)) {
213        delete newMap;
214        return NULL;
215    }
216
217    return newMap;
218}
219
220/*
221 * Uncompress an entry, in its entirety, into the provided output buffer.
222 *
223 * This doesn't verify the data's CRC, which might be useful for
224 * uncompressed data.  The caller should be able to manage it.
225 */
226bool ZipFileRO::uncompressEntry(ZipEntryRO entry, void* buffer, size_t size) const
227{
228    _ZipEntryRO *zipEntry = reinterpret_cast<_ZipEntryRO*>(entry);
229    const int32_t error = ExtractToMemory(mHandle, &(zipEntry->entry),
230        (uint8_t*) buffer, size);
231    if (error) {
232        ALOGW("ExtractToMemory failed with %s", ErrorCodeString(error));
233        return false;
234    }
235
236    return true;
237}
238
239/*
240 * Uncompress an entry, in its entirety, to an open file descriptor.
241 *
242 * This doesn't verify the data's CRC, but probably should.
243 */
244bool ZipFileRO::uncompressEntry(ZipEntryRO entry, int fd) const
245{
246    _ZipEntryRO *zipEntry = reinterpret_cast<_ZipEntryRO*>(entry);
247    const int32_t error = ExtractEntryToFile(mHandle, &(zipEntry->entry), fd);
248    if (error) {
249        ALOGW("ExtractToMemory failed with %s", ErrorCodeString(error));
250        return false;
251    }
252
253    return true;
254}
255