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 * Some utility functions for use with command-line utilities.
18 */
19 #include "DexFile.h"
20 #include "ZipArchive.h"
21 #include "CmdUtils.h"
22
23 #include <stdlib.h>
24 #include <string.h>
25 #include <strings.h>
26 #include <fcntl.h>
27 #include <errno.h>
28
29 #ifndef O_BINARY
30 #define O_BINARY 0
31 #endif
32
33 /*
34 * Extract "classes.dex" from archive file.
35 *
36 * If "quiet" is set, don't report common errors.
37 */
dexUnzipToFile(const char * zipFileName,const char * outFileName,bool quiet)38 UnzipToFileResult dexUnzipToFile(const char* zipFileName,
39 const char* outFileName, bool quiet)
40 {
41 UnzipToFileResult result = kUTFRSuccess;
42 static const char* kFileToExtract = "classes.dex";
43 ZipArchiveHandle archive;
44 ZipEntry entry;
45 bool unlinkOnFailure = false;
46 int fd = -1;
47
48 if (dexZipOpenArchive(zipFileName, &archive) != 0) {
49 if (!quiet) {
50 fprintf(stderr, "Unable to open '%s' as zip archive\n",
51 zipFileName);
52 }
53 result = kUTFRNotZip;
54 goto bail;
55 }
56
57 fd = open(outFileName, O_RDWR | O_CREAT | O_EXCL, 0600);
58 if (fd < 0) {
59 fprintf(stderr, "Unable to create output file '%s': %s\n",
60 outFileName, strerror(errno));
61 result = kUTFROutputFileProblem;
62 goto bail;
63 }
64
65 unlinkOnFailure = true;
66
67 if (dexZipFindEntry(archive, kFileToExtract, &entry) != 0) {
68 if (!quiet) {
69 fprintf(stderr, "Unable to find '%s' in '%s'\n",
70 kFileToExtract, zipFileName);
71 }
72 result = kUTFRNoClassesDex;
73 goto bail;
74 }
75
76 if (dexZipExtractEntryToFile(archive, &entry, fd) != 0) {
77 fprintf(stderr, "Extract of '%s' from '%s' failed\n",
78 kFileToExtract, zipFileName);
79 result = kUTFRBadZip;
80 goto bail;
81 }
82
83 bail:
84 if (fd >= 0)
85 close(fd);
86 if (unlinkOnFailure && result != kUTFRSuccess)
87 unlink(outFileName);
88 dexZipCloseArchive(archive);
89 return result;
90 }
91
92 /*
93 * Map the specified DEX file read-only (possibly after expanding it into a
94 * temp file from a Jar). Pass in a MemMapping struct to hold the info.
95 * If the file is an unoptimized DEX file, then byte-swapping and structural
96 * verification are performed on it before the memory is made read-only.
97 *
98 * The temp file is deleted after the map succeeds.
99 *
100 * This is intended for use by tools (e.g. dexdump) that need to get a
101 * read-only copy of a DEX file that could be in a number of different states.
102 *
103 * If "tempFileName" is NULL, a default value is used. The temp file is
104 * deleted after the map succeeds.
105 *
106 * If "quiet" is set, don't report common errors.
107 *
108 * Returns 0 (kUTFRSuccess) on success.
109 */
dexOpenAndMap(const char * fileName,const char * tempFileName,MemMapping * pMap,bool quiet)110 UnzipToFileResult dexOpenAndMap(const char* fileName, const char* tempFileName,
111 MemMapping* pMap, bool quiet)
112 {
113 UnzipToFileResult result = kUTFRGenericFailure;
114 int len = strlen(fileName);
115 char tempNameBuf[32];
116 bool removeTemp = false;
117 int fd = -1;
118
119 if (len < 5) {
120 if (!quiet) {
121 fprintf(stderr,
122 "ERROR: filename must end in .dex, .zip, .jar, or .apk\n");
123 }
124 result = kUTFRBadArgs;
125 goto bail;
126 }
127
128 if (strcasecmp(fileName + len -3, "dex") != 0) {
129 if (tempFileName == NULL) {
130 /*
131 * Try .zip/.jar/.apk, all of which are Zip archives with
132 * "classes.dex" inside. We need to extract the compressed
133 * data to a temp file, the location of which varies.
134 *
135 * On the device we must use /sdcard because most other
136 * directories aren't writable (either because of permissions
137 * or because the volume is mounted read-only). On desktop
138 * it's nice to use the designated temp directory.
139 */
140 if (access("/tmp", W_OK) == 0) {
141 sprintf(tempNameBuf, "/tmp/dex-temp-%d", getpid());
142 } else if (access("/sdcard", W_OK) == 0) {
143 sprintf(tempNameBuf, "/sdcard/dex-temp-%d", getpid());
144 } else {
145 fprintf(stderr,
146 "NOTE: /tmp and /sdcard unavailable for temp files\n");
147 sprintf(tempNameBuf, "dex-temp-%d", getpid());
148 }
149
150 tempFileName = tempNameBuf;
151 }
152
153 result = dexUnzipToFile(fileName, tempFileName, quiet);
154
155 if (result == kUTFRSuccess) {
156 //printf("+++ Good unzip to '%s'\n", tempFileName);
157 fileName = tempFileName;
158 removeTemp = true;
159 } else if (result == kUTFRNotZip) {
160 if (!quiet) {
161 fprintf(stderr, "Not Zip, retrying as DEX\n");
162 }
163 } else {
164 if (!quiet && result == kUTFRNoClassesDex) {
165 fprintf(stderr, "Zip has no classes.dex\n");
166 }
167 goto bail;
168 }
169 }
170
171 result = kUTFRGenericFailure;
172
173 /*
174 * Pop open the (presumed) DEX file.
175 */
176 fd = open(fileName, O_RDONLY | O_BINARY);
177 if (fd < 0) {
178 if (!quiet) {
179 fprintf(stderr, "ERROR: unable to open '%s': %s\n",
180 fileName, strerror(errno));
181 }
182 goto bail;
183 }
184
185 if (sysMapFileInShmemWritableReadOnly(fd, pMap) != 0) {
186 fprintf(stderr, "ERROR: Unable to map '%s'\n", fileName);
187 goto bail;
188 }
189
190 /*
191 * This call will fail if the file exists on a filesystem that
192 * doesn't support mprotect(). If that's the case, then the file
193 * will have already been mapped private-writable by the previous
194 * call, so we don't need to do anything special if this call
195 * returns non-zero.
196 */
197 sysChangeMapAccess(pMap->addr, pMap->length, true, pMap);
198
199 if (dexSwapAndVerifyIfNecessary((u1*) pMap->addr, pMap->length)) {
200 fprintf(stderr, "ERROR: Failed structural verification of '%s'\n",
201 fileName);
202 goto bail;
203 }
204
205 /*
206 * Similar to above, this call will fail if the file wasn't ever
207 * read-only to begin with. This is innocuous, though it is
208 * undesirable from a memory hygiene perspective.
209 */
210 sysChangeMapAccess(pMap->addr, pMap->length, false, pMap);
211
212 /*
213 * Success! Close the file and return with the start/length in pMap.
214 */
215 result = kUTFRSuccess;
216
217 bail:
218 if (fd >= 0)
219 close(fd);
220 if (removeTemp) {
221 /* this will fail if the OS doesn't allow removal of a mapped file */
222 if (unlink(tempFileName) != 0) {
223 fprintf(stderr, "WARNING: unable to remove temp '%s'\n",
224 tempFileName);
225 }
226 }
227 return result;
228 }
229