1 #include <dirent.h>
2 #include <inttypes.h>
3 #include <sys/stat.h>
4
5 #include "idmap.h"
6
7 #include <UniquePtr.h>
8 #include <androidfw/ResourceTypes.h>
9 #include <androidfw/StreamingZipInflater.h>
10 #include <androidfw/ZipFileRO.h>
11 #include <private/android_filesystem_config.h> // for AID_SYSTEM
12 #include <utils/SortedVector.h>
13 #include <utils/String16.h>
14 #include <utils/String8.h>
15
16 #define NO_OVERLAY_TAG (-1000)
17
18 using namespace android;
19
20 namespace {
21 struct Overlay {
Overlay__anon1f91dc7f0111::Overlay22 Overlay() {}
Overlay__anon1f91dc7f0111::Overlay23 Overlay(const String8& a, const String8& i, int p) :
24 apk_path(a), idmap_path(i), priority(p) {}
25
operator <__anon1f91dc7f0111::Overlay26 bool operator<(Overlay const& rhs) const
27 {
28 // Note: order is reversed by design
29 return rhs.priority < priority;
30 }
31
32 String8 apk_path;
33 String8 idmap_path;
34 int priority;
35 };
36
writePackagesList(const char * filename,const SortedVector<Overlay> & overlayVector)37 bool writePackagesList(const char *filename, const SortedVector<Overlay>& overlayVector)
38 {
39 FILE* fout = fopen(filename, "w");
40 if (fout == NULL) {
41 return false;
42 }
43
44 for (size_t i = 0; i < overlayVector.size(); ++i) {
45 const Overlay& overlay = overlayVector[i];
46 fprintf(fout, "%s %s\n", overlay.apk_path.string(), overlay.idmap_path.string());
47 }
48
49 fclose(fout);
50
51 // Make file world readable since Zygote (running as root) will read
52 // it when creating the initial AssetManger object
53 const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; // 0644
54 if (chmod(filename, mode) == -1) {
55 unlink(filename);
56 return false;
57 }
58
59 return true;
60 }
61
flatten_path(const char * path)62 String8 flatten_path(const char *path)
63 {
64 String16 tmp(path);
65 tmp.replaceAll('/', '@');
66 return String8(tmp);
67 }
68
parse_overlay_tag(const ResXMLTree & parser,const char * target_package_name)69 int parse_overlay_tag(const ResXMLTree& parser, const char *target_package_name)
70 {
71 const size_t N = parser.getAttributeCount();
72 String16 target;
73 int priority = -1;
74 for (size_t i = 0; i < N; ++i) {
75 size_t len;
76 String16 key(parser.getAttributeName(i, &len));
77 if (key == String16("targetPackage")) {
78 const char16_t *p = parser.getAttributeStringValue(i, &len);
79 if (p != NULL) {
80 target = String16(p, len);
81 }
82 } else if (key == String16("priority")) {
83 Res_value v;
84 if (parser.getAttributeValue(i, &v) == sizeof(Res_value)) {
85 priority = v.data;
86 if (priority < 0 || priority > 9999) {
87 return -1;
88 }
89 }
90 }
91 }
92 if (target == String16(target_package_name)) {
93 return priority;
94 }
95 return NO_OVERLAY_TAG;
96 }
97
parse_manifest(const void * data,size_t size,const char * target_package_name)98 int parse_manifest(const void *data, size_t size, const char *target_package_name)
99 {
100 ResXMLTree parser;
101 parser.setTo(data, size);
102 if (parser.getError() != NO_ERROR) {
103 ALOGD("%s failed to init xml parser, error=0x%08x\n", __FUNCTION__, parser.getError());
104 return -1;
105 }
106
107 ResXMLParser::event_code_t type;
108 do {
109 type = parser.next();
110 if (type == ResXMLParser::START_TAG) {
111 size_t len;
112 String16 tag(parser.getElementName(&len));
113 if (tag == String16("overlay")) {
114 return parse_overlay_tag(parser, target_package_name);
115 }
116 }
117 } while (type != ResXMLParser::BAD_DOCUMENT && type != ResXMLParser::END_DOCUMENT);
118
119 return NO_OVERLAY_TAG;
120 }
121
parse_apk(const char * path,const char * target_package_name)122 int parse_apk(const char *path, const char *target_package_name)
123 {
124 UniquePtr<ZipFileRO> zip(ZipFileRO::open(path));
125 if (zip.get() == NULL) {
126 ALOGW("%s: failed to open zip %s\n", __FUNCTION__, path);
127 return -1;
128 }
129 ZipEntryRO entry;
130 if ((entry = zip->findEntryByName("AndroidManifest.xml")) == NULL) {
131 ALOGW("%s: failed to find entry AndroidManifest.xml\n", __FUNCTION__);
132 return -1;
133 }
134 uint32_t uncompLen = 0;
135 uint16_t method;
136 if (!zip->getEntryInfo(entry, &method, &uncompLen, NULL, NULL, NULL, NULL)) {
137 ALOGW("%s: failed to read entry info\n", __FUNCTION__);
138 return -1;
139 }
140 if (method != ZipFileRO::kCompressDeflated) {
141 ALOGW("%s: cannot handle zip compression method %" PRIu16 "\n", __FUNCTION__, method);
142 return -1;
143 }
144 FileMap *dataMap = zip->createEntryFileMap(entry);
145 if (dataMap == NULL) {
146 ALOGW("%s: failed to create FileMap\n", __FUNCTION__);
147 return -1;
148 }
149 char *buf = new char[uncompLen];
150 if (NULL == buf) {
151 ALOGW("%s: failed to allocate %" PRIu32 " byte\n", __FUNCTION__, uncompLen);
152 delete dataMap;
153 return -1;
154 }
155 StreamingZipInflater inflater(dataMap, uncompLen);
156 if (inflater.read(buf, uncompLen) < 0) {
157 ALOGW("%s: failed to inflate %" PRIu32 " byte\n", __FUNCTION__, uncompLen);
158 delete[] buf;
159 delete dataMap;
160 return -1;
161 }
162
163 int priority = parse_manifest(buf, static_cast<size_t>(uncompLen), target_package_name);
164 delete[] buf;
165 delete dataMap;
166 return priority;
167 }
168 }
169
idmap_scan(const char * overlay_dir,const char * target_package_name,const char * target_apk_path,const char * idmap_dir)170 int idmap_scan(const char *overlay_dir, const char *target_package_name,
171 const char *target_apk_path, const char *idmap_dir)
172 {
173 String8 filename = String8(idmap_dir);
174 filename.appendPath("overlays.list");
175 if (unlink(filename.string()) != 0 && errno != ENOENT) {
176 return EXIT_FAILURE;
177 }
178
179 DIR *dir = opendir(overlay_dir);
180 if (dir == NULL) {
181 return EXIT_FAILURE;
182 }
183
184 SortedVector<Overlay> overlayVector;
185 struct dirent *dirent;
186 while ((dirent = readdir(dir)) != NULL) {
187 struct stat st;
188 char overlay_apk_path[PATH_MAX + 1];
189 snprintf(overlay_apk_path, PATH_MAX, "%s/%s", overlay_dir, dirent->d_name);
190 if (stat(overlay_apk_path, &st) < 0) {
191 continue;
192 }
193 if (!S_ISREG(st.st_mode)) {
194 continue;
195 }
196
197 int priority = parse_apk(overlay_apk_path, target_package_name);
198 if (priority < 0) {
199 continue;
200 }
201
202 String8 idmap_path(idmap_dir);
203 idmap_path.appendPath(flatten_path(overlay_apk_path + 1));
204 idmap_path.append("@idmap");
205
206 if (idmap_create_path(target_apk_path, overlay_apk_path, idmap_path.string()) != 0) {
207 ALOGE("error: failed to create idmap for target=%s overlay=%s idmap=%s\n",
208 target_apk_path, overlay_apk_path, idmap_path.string());
209 continue;
210 }
211
212 Overlay overlay(String8(overlay_apk_path), idmap_path, priority);
213 overlayVector.add(overlay);
214 }
215
216 closedir(dir);
217
218 if (!writePackagesList(filename.string(), overlayVector)) {
219 return EXIT_FAILURE;
220 }
221
222 return EXIT_SUCCESS;
223 }
224