1#include <dirent.h> 2#include <inttypes.h> 3#include <sys/stat.h> 4 5#include "idmap.h" 6 7#include <memory> 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 18using namespace android; 19 20namespace { 21 struct Overlay { 22 Overlay() {} 23 Overlay(const String8& a, const String8& i, int p) : 24 apk_path(a), idmap_path(i), priority(p) {} 25 26 bool operator<(Overlay const& rhs) const 27 { 28 return rhs.priority > priority; 29 } 30 31 String8 apk_path; 32 String8 idmap_path; 33 int priority; 34 }; 35 36 bool writePackagesList(const char *filename, const SortedVector<Overlay>& overlayVector) 37 { 38 FILE* fout = fopen(filename, "w"); 39 if (fout == NULL) { 40 return false; 41 } 42 43 for (size_t i = 0; i < overlayVector.size(); ++i) { 44 const Overlay& overlay = overlayVector[i]; 45 fprintf(fout, "%s %s\n", overlay.apk_path.string(), overlay.idmap_path.string()); 46 } 47 48 fclose(fout); 49 50 // Make file world readable since Zygote (running as root) will read 51 // it when creating the initial AssetManger object 52 const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; // 0644 53 if (chmod(filename, mode) == -1) { 54 unlink(filename); 55 return false; 56 } 57 58 return true; 59 } 60 61 String8 flatten_path(const char *path) 62 { 63 String16 tmp(path); 64 tmp.replaceAll('/', '@'); 65 return String8(tmp); 66 } 67 68 int parse_overlay_tag(const ResXMLTree& parser, const char *target_package_name) 69 { 70 const size_t N = parser.getAttributeCount(); 71 String16 target; 72 int priority = -1; 73 for (size_t i = 0; i < N; ++i) { 74 size_t len; 75 String16 key(parser.getAttributeName(i, &len)); 76 if (key == String16("targetPackage")) { 77 const char16_t *p = parser.getAttributeStringValue(i, &len); 78 if (p != NULL) { 79 target = String16(p, len); 80 } 81 } else if (key == String16("priority")) { 82 Res_value v; 83 if (parser.getAttributeValue(i, &v) == sizeof(Res_value)) { 84 priority = v.data; 85 if (priority < 0 || priority > 9999) { 86 return -1; 87 } 88 } 89 } 90 } 91 if (target == String16(target_package_name)) { 92 return priority; 93 } 94 return NO_OVERLAY_TAG; 95 } 96 97 int parse_manifest(const void *data, size_t size, const char *target_package_name) 98 { 99 ResXMLTree parser; 100 parser.setTo(data, size); 101 if (parser.getError() != NO_ERROR) { 102 ALOGD("%s failed to init xml parser, error=0x%08x\n", __FUNCTION__, parser.getError()); 103 return -1; 104 } 105 106 ResXMLParser::event_code_t type; 107 do { 108 type = parser.next(); 109 if (type == ResXMLParser::START_TAG) { 110 size_t len; 111 String16 tag(parser.getElementName(&len)); 112 if (tag == String16("overlay")) { 113 return parse_overlay_tag(parser, target_package_name); 114 } 115 } 116 } while (type != ResXMLParser::BAD_DOCUMENT && type != ResXMLParser::END_DOCUMENT); 117 118 return NO_OVERLAY_TAG; 119 } 120 121 int parse_apk(const char *path, const char *target_package_name) 122 { 123 std::unique_ptr<ZipFileRO> zip(ZipFileRO::open(path)); 124 if (zip.get() == NULL) { 125 ALOGW("%s: failed to open zip %s\n", __FUNCTION__, path); 126 return -1; 127 } 128 ZipEntryRO entry; 129 if ((entry = zip->findEntryByName("AndroidManifest.xml")) == NULL) { 130 ALOGW("%s: failed to find entry AndroidManifest.xml\n", __FUNCTION__); 131 return -1; 132 } 133 uint32_t uncompLen = 0; 134 uint16_t method; 135 if (!zip->getEntryInfo(entry, &method, &uncompLen, NULL, NULL, NULL, NULL)) { 136 ALOGW("%s: failed to read entry info\n", __FUNCTION__); 137 return -1; 138 } 139 if (method != ZipFileRO::kCompressDeflated) { 140 ALOGW("%s: cannot handle zip compression method %" PRIu16 "\n", __FUNCTION__, method); 141 return -1; 142 } 143 FileMap *dataMap = zip->createEntryFileMap(entry); 144 if (dataMap == NULL) { 145 ALOGW("%s: failed to create FileMap\n", __FUNCTION__); 146 return -1; 147 } 148 char *buf = new char[uncompLen]; 149 if (NULL == buf) { 150 ALOGW("%s: failed to allocate %" PRIu32 " byte\n", __FUNCTION__, uncompLen); 151 delete dataMap; 152 return -1; 153 } 154 StreamingZipInflater inflater(dataMap, uncompLen); 155 if (inflater.read(buf, uncompLen) < 0) { 156 ALOGW("%s: failed to inflate %" PRIu32 " byte\n", __FUNCTION__, uncompLen); 157 delete[] buf; 158 delete dataMap; 159 return -1; 160 } 161 162 int priority = parse_manifest(buf, static_cast<size_t>(uncompLen), target_package_name); 163 delete[] buf; 164 delete dataMap; 165 return priority; 166 } 167} 168 169int idmap_scan(const char *target_package_name, const char *target_apk_path, 170 const char *idmap_dir, const android::Vector<const char *> *overlay_dirs) 171{ 172 String8 filename = String8(idmap_dir); 173 filename.appendPath("overlays.list"); 174 if (unlink(filename.string()) != 0 && errno != ENOENT) { 175 return EXIT_FAILURE; 176 } 177 178 SortedVector<Overlay> overlayVector; 179 const size_t N = overlay_dirs->size(); 180 for (size_t i = 0; i < N; ++i) { 181 const char *overlay_dir = overlay_dirs->itemAt(i); 182 DIR *dir = opendir(overlay_dir); 183 if (dir == NULL) { 184 return EXIT_FAILURE; 185 } 186 187 struct dirent *dirent; 188 while ((dirent = readdir(dir)) != NULL) { 189 struct stat st; 190 char overlay_apk_path[PATH_MAX + 1]; 191 snprintf(overlay_apk_path, PATH_MAX, "%s/%s", overlay_dir, dirent->d_name); 192 if (stat(overlay_apk_path, &st) < 0) { 193 continue; 194 } 195 if (!S_ISREG(st.st_mode)) { 196 continue; 197 } 198 199 int priority = parse_apk(overlay_apk_path, target_package_name); 200 if (priority < 0) { 201 continue; 202 } 203 204 String8 idmap_path(idmap_dir); 205 idmap_path.appendPath(flatten_path(overlay_apk_path + 1)); 206 idmap_path.append("@idmap"); 207 208 if (idmap_create_path(target_apk_path, overlay_apk_path, idmap_path.string()) != 0) { 209 ALOGE("error: failed to create idmap for target=%s overlay=%s idmap=%s\n", 210 target_apk_path, overlay_apk_path, idmap_path.string()); 211 continue; 212 } 213 214 Overlay overlay(String8(overlay_apk_path), idmap_path, priority); 215 overlayVector.add(overlay); 216 } 217 218 closedir(dir); 219 } 220 221 if (!writePackagesList(filename.string(), overlayVector)) { 222 return EXIT_FAILURE; 223 } 224 225 return EXIT_SUCCESS; 226} 227