diff options
Diffstat (limited to 'cmds/idmap/scan.cpp')
| -rw-r--r-- | cmds/idmap/scan.cpp | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/cmds/idmap/scan.cpp b/cmds/idmap/scan.cpp new file mode 100644 index 000000000000..8122395d8061 --- /dev/null +++ b/cmds/idmap/scan.cpp @@ -0,0 +1,240 @@ +#include <dirent.h> +#include <inttypes.h> +#include <sys/file.h> +#include <sys/stat.h> + +#include "idmap.h" + +#include <memory> +#include <androidfw/ResourceTypes.h> +#include <androidfw/StreamingZipInflater.h> +#include <androidfw/ZipFileRO.h> +#include <private/android_filesystem_config.h> // for AID_SYSTEM +#include <utils/SortedVector.h> +#include <utils/String16.h> +#include <utils/String8.h> + +#define NO_OVERLAY_TAG (-1000) + +using namespace android; + +namespace { + struct Overlay { + Overlay() {} + Overlay(const String8& a, const String8& i, int p) : + apk_path(a), idmap_path(i), priority(p) {} + + bool operator<(Overlay const& rhs) const + { + return rhs.priority > priority; + } + + String8 apk_path; + String8 idmap_path; + int priority; + }; + + bool writePackagesList(const char *filename, const SortedVector<Overlay>& overlayVector) + { + // the file is opened for appending so that it doesn't get truncated + // before we can guarantee mutual exclusion via the flock + FILE* fout = fopen(filename, "a"); + if (fout == NULL) { + return false; + } + + if (TEMP_FAILURE_RETRY(flock(fileno(fout), LOCK_EX)) != 0) { + fclose(fout); + return false; + } + + if (TEMP_FAILURE_RETRY(ftruncate(fileno(fout), 0)) != 0) { + TEMP_FAILURE_RETRY(flock(fileno(fout), LOCK_UN)); + fclose(fout); + return false; + } + + for (size_t i = 0; i < overlayVector.size(); ++i) { + const Overlay& overlay = overlayVector[i]; + fprintf(fout, "%s %s\n", overlay.apk_path.string(), overlay.idmap_path.string()); + } + + TEMP_FAILURE_RETRY(fflush(fout)); + TEMP_FAILURE_RETRY(flock(fileno(fout), LOCK_UN)); + fclose(fout); + + // Make file world readable since Zygote (running as root) will read + // it when creating the initial AssetManger object + const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; // 0644 + if (chmod(filename, mode) == -1) { + unlink(filename); + return false; + } + + return true; + } + + String8 flatten_path(const char *path) + { + String16 tmp(path); + tmp.replaceAll('/', '@'); + return String8(tmp); + } + + int parse_overlay_tag(const ResXMLTree& parser, const char *target_package_name) + { + const size_t N = parser.getAttributeCount(); + String16 target; + int priority = -1; + for (size_t i = 0; i < N; ++i) { + size_t len; + String16 key(parser.getAttributeName(i, &len)); + if (key == String16("targetPackage")) { + const char16_t *p = parser.getAttributeStringValue(i, &len); + if (p != NULL) { + target = String16(p, len); + } + } else if (key == String16("priority")) { + Res_value v; + if (parser.getAttributeValue(i, &v) == sizeof(Res_value)) { + priority = v.data; + if (priority < 0 || priority > 9999) { + return -1; + } + } + } + } + if (target == String16(target_package_name)) { + return priority; + } + return NO_OVERLAY_TAG; + } + + int parse_manifest(const void *data, size_t size, const char *target_package_name) + { + ResXMLTree parser; + parser.setTo(data, size); + if (parser.getError() != NO_ERROR) { + ALOGD("%s failed to init xml parser, error=0x%08x\n", __FUNCTION__, parser.getError()); + return -1; + } + + ResXMLParser::event_code_t type; + do { + type = parser.next(); + if (type == ResXMLParser::START_TAG) { + size_t len; + String16 tag(parser.getElementName(&len)); + if (tag == String16("overlay")) { + return parse_overlay_tag(parser, target_package_name); + } + } + } while (type != ResXMLParser::BAD_DOCUMENT && type != ResXMLParser::END_DOCUMENT); + + return NO_OVERLAY_TAG; + } + + int parse_apk(const char *path, const char *target_package_name) + { + std::unique_ptr<ZipFileRO> zip(ZipFileRO::open(path)); + if (zip.get() == NULL) { + ALOGW("%s: failed to open zip %s\n", __FUNCTION__, path); + return -1; + } + ZipEntryRO entry; + if ((entry = zip->findEntryByName("AndroidManifest.xml")) == NULL) { + ALOGW("%s: failed to find entry AndroidManifest.xml\n", __FUNCTION__); + return -1; + } + uint32_t uncompLen = 0; + uint16_t method; + if (!zip->getEntryInfo(entry, &method, &uncompLen, NULL, NULL, NULL, NULL)) { + ALOGW("%s: failed to read entry info\n", __FUNCTION__); + return -1; + } + if (method != ZipFileRO::kCompressDeflated) { + ALOGW("%s: cannot handle zip compression method %" PRIu16 "\n", __FUNCTION__, method); + return -1; + } + FileMap *dataMap = zip->createEntryFileMap(entry); + if (dataMap == NULL) { + ALOGW("%s: failed to create FileMap\n", __FUNCTION__); + return -1; + } + char *buf = new char[uncompLen]; + if (NULL == buf) { + ALOGW("%s: failed to allocate %" PRIu32 " byte\n", __FUNCTION__, uncompLen); + delete dataMap; + return -1; + } + StreamingZipInflater inflater(dataMap, uncompLen); + if (inflater.read(buf, uncompLen) < 0) { + ALOGW("%s: failed to inflate %" PRIu32 " byte\n", __FUNCTION__, uncompLen); + delete[] buf; + delete dataMap; + return -1; + } + + int priority = parse_manifest(buf, static_cast<size_t>(uncompLen), target_package_name); + delete[] buf; + delete dataMap; + return priority; + } +} + +int idmap_scan(const char *target_package_name, const char *target_apk_path, + const char *idmap_dir, const android::Vector<const char *> *overlay_dirs) +{ + String8 filename = String8(idmap_dir); + filename.appendPath("overlays.list"); + + SortedVector<Overlay> overlayVector; + const size_t N = overlay_dirs->size(); + for (size_t i = 0; i < N; ++i) { + const char *overlay_dir = overlay_dirs->itemAt(i); + DIR *dir = opendir(overlay_dir); + if (dir == NULL) { + return EXIT_FAILURE; + } + + struct dirent *dirent; + while ((dirent = readdir(dir)) != NULL) { + struct stat st; + char overlay_apk_path[PATH_MAX + 1]; + snprintf(overlay_apk_path, PATH_MAX, "%s/%s", overlay_dir, dirent->d_name); + if (stat(overlay_apk_path, &st) < 0) { + continue; + } + if (!S_ISREG(st.st_mode)) { + continue; + } + + int priority = parse_apk(overlay_apk_path, target_package_name); + if (priority < 0) { + continue; + } + + String8 idmap_path(idmap_dir); + idmap_path.appendPath(flatten_path(overlay_apk_path + 1)); + idmap_path.append("@idmap"); + + if (idmap_create_path(target_apk_path, overlay_apk_path, idmap_path.string()) != 0) { + ALOGE("error: failed to create idmap for target=%s overlay=%s idmap=%s\n", + target_apk_path, overlay_apk_path, idmap_path.string()); + continue; + } + + Overlay overlay(String8(overlay_apk_path), idmap_path, priority); + overlayVector.add(overlay); + } + + closedir(dir); + } + + if (!writePackagesList(filename.string(), overlayVector)) { + return EXIT_FAILURE; + } + + return EXIT_SUCCESS; +} + |