1 #include "idmap.h"
2
3 #include <UniquePtr.h>
4 #include <androidfw/ResourceTypes.h>
5 #include <androidfw/StreamingZipInflater.h>
6 #include <androidfw/ZipFileRO.h>
7 #include <private/android_filesystem_config.h> // for AID_SYSTEM
8 #include <utils/SortedVector.h>
9 #include <utils/String16.h>
10 #include <utils/String8.h>
11
12 #include <dirent.h>
13
14 #define NO_OVERLAY_TAG (-1000)
15
16 using namespace android;
17
18 namespace {
19 struct Overlay {
Overlay__anonbd9382230111::Overlay20 Overlay() {}
Overlay__anonbd9382230111::Overlay21 Overlay(const String8& a, const String8& i, int p) :
22 apk_path(a), idmap_path(i), priority(p) {}
23
operator <__anonbd9382230111::Overlay24 bool operator<(Overlay const& rhs) const
25 {
26 // Note: order is reversed by design
27 return rhs.priority < priority;
28 }
29
30 String8 apk_path;
31 String8 idmap_path;
32 int priority;
33 };
34
writePackagesList(const char * filename,const SortedVector<Overlay> & overlayVector)35 bool writePackagesList(const char *filename, const SortedVector<Overlay>& overlayVector)
36 {
37 FILE* fout = fopen(filename, "w");
38 if (fout == NULL) {
39 return false;
40 }
41
42 for (size_t i = 0; i < overlayVector.size(); ++i) {
43 const Overlay& overlay = overlayVector[i];
44 fprintf(fout, "%s %s\n", overlay.apk_path.string(), overlay.idmap_path.string());
45 }
46
47 fclose(fout);
48
49 // Make file world readable since Zygote (running as root) will read
50 // it when creating the initial AssetManger object
51 const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; // 0644
52 if (chmod(filename, mode) == -1) {
53 unlink(filename);
54 return false;
55 }
56
57 return true;
58 }
59
flatten_path(const char * path)60 String8 flatten_path(const char *path)
61 {
62 String16 tmp(path);
63 tmp.replaceAll('/', '@');
64 return String8(tmp);
65 }
66
mkdir_p(const String8 & path,uid_t uid,gid_t gid)67 int mkdir_p(const String8& path, uid_t uid, gid_t gid)
68 {
69 static const mode_t mode =
70 S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH | S_IXOTH;
71 struct stat st;
72
73 if (stat(path.string(), &st) == 0) {
74 return 0;
75 }
76 if (mkdir_p(path.getPathDir(), uid, gid) < 0) {
77 return -1;
78 }
79 if (mkdir(path.string(), 0755) != 0) {
80 return -1;
81 }
82 if (chown(path.string(), uid, gid) == -1) {
83 return -1;
84 }
85 if (chmod(path.string(), mode) == -1) {
86 return -1;
87 }
88 return 0;
89 }
90
parse_overlay_tag(const ResXMLTree & parser,const char * target_package_name)91 int parse_overlay_tag(const ResXMLTree& parser, const char *target_package_name)
92 {
93 const size_t N = parser.getAttributeCount();
94 String16 target;
95 int priority = -1;
96 for (size_t i = 0; i < N; ++i) {
97 size_t len;
98 String16 key(parser.getAttributeName(i, &len));
99 if (key == String16("targetPackage")) {
100 const uint16_t *p = parser.getAttributeStringValue(i, &len);
101 if (p) {
102 target = String16(p, len);
103 }
104 } else if (key == String16("priority")) {
105 Res_value v;
106 if (parser.getAttributeValue(i, &v) == sizeof(Res_value)) {
107 priority = v.data;
108 if (priority < 0 || priority > 9999) {
109 return -1;
110 }
111 }
112 }
113 }
114 if (target == String16(target_package_name)) {
115 return priority;
116 }
117 return NO_OVERLAY_TAG;
118 }
119
parse_manifest(const void * data,size_t size,const char * target_package_name)120 int parse_manifest(const void *data, size_t size, const char *target_package_name)
121 {
122 ResXMLTree parser;
123 parser.setTo(data, size);
124 if (parser.getError() != NO_ERROR) {
125 ALOGD("%s failed to init xml parser, error=0x%08x\n", __FUNCTION__, parser.getError());
126 return -1;
127 }
128
129 ResXMLParser::event_code_t type;
130 do {
131 type = parser.next();
132 if (type == ResXMLParser::START_TAG) {
133 size_t len;
134 String16 tag(parser.getElementName(&len));
135 if (tag == String16("overlay")) {
136 return parse_overlay_tag(parser, target_package_name);
137 }
138 }
139 } while (type != ResXMLParser::BAD_DOCUMENT && type != ResXMLParser::END_DOCUMENT);
140
141 return NO_OVERLAY_TAG;
142 }
143
parse_apk(const char * path,const char * target_package_name)144 int parse_apk(const char *path, const char *target_package_name)
145 {
146 UniquePtr<ZipFileRO> zip(ZipFileRO::open(path));
147 if (zip.get() == NULL) {
148 ALOGW("%s: failed to open zip %s\n", __FUNCTION__, path);
149 return -1;
150 }
151 ZipEntryRO entry;
152 if ((entry = zip->findEntryByName("AndroidManifest.xml")) == NULL) {
153 ALOGW("%s: failed to find entry AndroidManifest.xml\n", __FUNCTION__);
154 return -1;
155 }
156 size_t uncompLen = 0;
157 int method;
158 if (!zip->getEntryInfo(entry, &method, &uncompLen, NULL, NULL, NULL, NULL)) {
159 ALOGW("%s: failed to read entry info\n", __FUNCTION__);
160 return -1;
161 }
162 if (method != ZipFileRO::kCompressDeflated) {
163 ALOGW("%s: cannot handle zip compression method %d\n", __FUNCTION__, method);
164 return -1;
165 }
166 FileMap *dataMap = zip->createEntryFileMap(entry);
167 if (!dataMap) {
168 ALOGW("%s: failed to create FileMap\n", __FUNCTION__);
169 return -1;
170 }
171 char *buf = new char[uncompLen];
172 if (NULL == buf) {
173 ALOGW("%s: failed to allocate %d byte\n", __FUNCTION__, uncompLen);
174 dataMap->release();
175 return -1;
176 }
177 StreamingZipInflater inflater(dataMap, uncompLen);
178 if (inflater.read(buf, uncompLen) < 0) {
179 ALOGW("%s: failed to inflate %d byte\n", __FUNCTION__, uncompLen);
180 delete[] buf;
181 dataMap->release();
182 return -1;
183 }
184
185 int priority = parse_manifest(buf, uncompLen, target_package_name);
186 delete[] buf;
187 dataMap->release();
188 return priority;
189 }
190 }
191
idmap_scan(const char * overlay_dir,const char * target_package_name,const char * target_apk_path,const char * idmap_dir)192 int idmap_scan(const char *overlay_dir, const char *target_package_name,
193 const char *target_apk_path, const char *idmap_dir)
194 {
195 String8 filename = String8(idmap_dir);
196 filename.appendPath("overlays.list");
197 if (unlink(filename.string()) != 0 && errno != ENOENT) {
198 return EXIT_FAILURE;
199 }
200
201 DIR *dir = opendir(overlay_dir);
202 if (dir == NULL) {
203 return EXIT_FAILURE;
204 }
205
206 SortedVector<Overlay> overlayVector;
207 struct dirent *dirent;
208 while ((dirent = readdir(dir)) != NULL) {
209 struct stat st;
210 char overlay_apk_path[PATH_MAX + 1];
211 snprintf(overlay_apk_path, PATH_MAX, "%s/%s", overlay_dir, dirent->d_name);
212 if (stat(overlay_apk_path, &st) < 0) {
213 continue;
214 }
215 if (!S_ISREG(st.st_mode)) {
216 continue;
217 }
218
219 int priority = parse_apk(overlay_apk_path, target_package_name);
220 if (priority < 0) {
221 continue;
222 }
223
224 String8 idmap_path(idmap_dir);
225 idmap_path.appendPath(flatten_path(overlay_apk_path + 1));
226 idmap_path.append("@idmap");
227
228 if (idmap_create_path(target_apk_path, overlay_apk_path, idmap_path.string()) != 0) {
229 ALOGE("error: failed to create idmap for target=%s overlay=%s idmap=%s\n",
230 target_apk_path, overlay_apk_path, idmap_path.string());
231 continue;
232 }
233
234 Overlay overlay(String8(overlay_apk_path), idmap_path, priority);
235 overlayVector.add(overlay);
236 }
237
238 closedir(dir);
239
240 if (!writePackagesList(filename.string(), overlayVector)) {
241 return EXIT_FAILURE;
242 }
243
244 return EXIT_SUCCESS;
245 }
246