Support starting fuse from a block map
Factor out a new function from ApplyFromSdcard that installs a package
from a local path. Inside this function, we start the fuse and choose the
type of data provider depending on the path string. And similar to the
existing logic, we treat the package as a block map if the path starts
with a '@'.
This is part of the effort to install larger than 2GiB packages on ILP32
devices.
Bug: 127071893
Test: Build a 32 bit sailfish and create a 3GiB OTA package. Sideload
the package, uncrypt and install the package from sdcard.
Change-Id: I328ea34fa530731acbce7554bfc3059313ad6ece
diff --git a/install/fuse_install.cpp b/install/fuse_install.cpp
new file mode 100644
index 0000000..ffde4a3
--- /dev/null
+++ b/install/fuse_install.cpp
@@ -0,0 +1,231 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "install/fuse_install.h"
+
+#include <dirent.h>
+#include <signal.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <algorithm>
+#include <functional>
+#include <memory>
+#include <string>
+#include <vector>
+
+#include <android-base/logging.h>
+#include <android-base/strings.h>
+
+#include "bootloader_message/bootloader_message.h"
+#include "fuse_provider.h"
+#include "fuse_sideload.h"
+#include "install/install.h"
+#include "otautil/roots.h"
+
+static constexpr const char* SDCARD_ROOT = "/sdcard";
+// How long (in seconds) we wait for the fuse-provided package file to
+// appear, before timing out.
+static constexpr int SDCARD_INSTALL_TIMEOUT = 10;
+
+// Set the BCB to reboot back into recovery (it won't resume the install from
+// sdcard though).
+static void SetSdcardUpdateBootloaderMessage() {
+ std::vector<std::string> options;
+ std::string err;
+ if (!update_bootloader_message(options, &err)) {
+ LOG(ERROR) << "Failed to set BCB message: " << err;
+ }
+}
+
+// Returns the selected filename, or an empty string.
+static std::string BrowseDirectory(const std::string& path, Device* device, RecoveryUI* ui) {
+ ensure_path_mounted(path);
+
+ std::unique_ptr<DIR, decltype(&closedir)> d(opendir(path.c_str()), closedir);
+ if (!d) {
+ PLOG(ERROR) << "error opening " << path;
+ return "";
+ }
+
+ std::vector<std::string> dirs;
+ std::vector<std::string> entries{ "../" }; // "../" is always the first entry.
+
+ dirent* de;
+ while ((de = readdir(d.get())) != nullptr) {
+ std::string name(de->d_name);
+
+ if (de->d_type == DT_DIR) {
+ // Skip "." and ".." entries.
+ if (name == "." || name == "..") continue;
+ dirs.push_back(name + "/");
+ } else if (de->d_type == DT_REG && (android::base::EndsWithIgnoreCase(name, ".zip") ||
+ android::base::EndsWithIgnoreCase(name, ".map"))) {
+ entries.push_back(name);
+ }
+ }
+
+ std::sort(dirs.begin(), dirs.end());
+ std::sort(entries.begin(), entries.end());
+
+ // Append dirs to the entries list.
+ entries.insert(entries.end(), dirs.begin(), dirs.end());
+
+ std::vector<std::string> headers{ "Choose a package to install:", path };
+
+ size_t chosen_item = 0;
+ while (true) {
+ chosen_item = ui->ShowMenu(
+ headers, entries, chosen_item, true,
+ std::bind(&Device::HandleMenuKey, device, std::placeholders::_1, std::placeholders::_2));
+
+ // Return if WaitKey() was interrupted.
+ if (chosen_item == static_cast<size_t>(RecoveryUI::KeyError::INTERRUPTED)) {
+ return "";
+ }
+
+ const std::string& item = entries[chosen_item];
+ if (chosen_item == 0) {
+ // Go up but continue browsing (if the caller is BrowseDirectory).
+ return "";
+ }
+
+ std::string new_path = path + "/" + item;
+ if (new_path.back() == '/') {
+ // Recurse down into a subdirectory.
+ new_path.pop_back();
+ std::string result = BrowseDirectory(new_path, device, ui);
+ if (!result.empty()) return result;
+ } else {
+ // Selected a zip file: return the path to the caller.
+ return new_path;
+ }
+ }
+
+ // Unreachable.
+}
+
+static bool StartInstallPackageFuse(std::string_view path) {
+ if (path.empty()) {
+ return false;
+ }
+
+ constexpr auto FUSE_BLOCK_SIZE = 65536;
+ bool is_block_map = android::base::ConsumePrefix(&path, "@");
+ auto file_data_reader =
+ is_block_map ? FuseBlockDataProvider::CreateFromBlockMap(std::string(path), FUSE_BLOCK_SIZE)
+ : FuseFileDataProvider::CreateFromFile(std::string(path), FUSE_BLOCK_SIZE);
+
+ if (!file_data_reader->Valid()) {
+ return false;
+ }
+
+ if (android::base::StartsWith(path, SDCARD_ROOT)) {
+ // The installation process expects to find the sdcard unmounted. Unmount it with MNT_DETACH so
+ // that our open file continues to work but new references see it as unmounted.
+ umount2(SDCARD_ROOT, MNT_DETACH);
+ }
+
+ return run_fuse_sideload(std::move(file_data_reader)) == 0;
+}
+
+InstallResult InstallWithFuseFromPath(std::string_view path, RecoveryUI* ui) {
+ // We used to use fuse in a thread as opposed to a process. Since accessing
+ // through fuse involves going from kernel to userspace to kernel, it leads
+ // to deadlock when a page fault occurs. (Bug: 26313124)
+ pid_t child;
+ if ((child = fork()) == 0) {
+ bool status = StartInstallPackageFuse(path);
+
+ _exit(status ? EXIT_SUCCESS : EXIT_FAILURE);
+ }
+
+ // FUSE_SIDELOAD_HOST_PATHNAME will start to exist once the fuse in child process is ready.
+ InstallResult result = INSTALL_ERROR;
+ int status;
+ bool waited = false;
+ for (int i = 0; i < SDCARD_INSTALL_TIMEOUT; ++i) {
+ if (waitpid(child, &status, WNOHANG) == -1) {
+ result = INSTALL_ERROR;
+ waited = true;
+ break;
+ }
+
+ struct stat sb;
+ if (stat(FUSE_SIDELOAD_HOST_PATHNAME, &sb) == -1) {
+ if (errno == ENOENT && i < SDCARD_INSTALL_TIMEOUT - 1) {
+ sleep(1);
+ continue;
+ } else {
+ LOG(ERROR) << "Timed out waiting for the fuse-provided package.";
+ result = INSTALL_ERROR;
+ kill(child, SIGKILL);
+ break;
+ }
+ }
+ auto package =
+ Package::CreateFilePackage(FUSE_SIDELOAD_HOST_PATHNAME,
+ std::bind(&RecoveryUI::SetProgress, ui, std::placeholders::_1));
+ result =
+ InstallPackage(package.get(), FUSE_SIDELOAD_HOST_PATHNAME, false, 0 /* retry_count */, ui);
+ break;
+ }
+
+ if (!waited) {
+ // Calling stat() on this magic filename signals the fuse
+ // filesystem to shut down.
+ struct stat sb;
+ stat(FUSE_SIDELOAD_HOST_EXIT_PATHNAME, &sb);
+
+ waitpid(child, &status, 0);
+ }
+
+ if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
+ LOG(ERROR) << "Error exit from the fuse process: " << WEXITSTATUS(status);
+ }
+
+ return result;
+}
+
+InstallResult ApplyFromSdcard(Device* device) {
+ auto ui = device->GetUI();
+ if (ensure_path_mounted(SDCARD_ROOT) != 0) {
+ LOG(ERROR) << "\n-- Couldn't mount " << SDCARD_ROOT << ".\n";
+ return INSTALL_ERROR;
+ }
+
+ std::string path = BrowseDirectory(SDCARD_ROOT, device, ui);
+ if (path.empty()) {
+ LOG(ERROR) << "\n-- No package file selected.\n";
+ ensure_path_unmounted(SDCARD_ROOT);
+ return INSTALL_ERROR;
+ }
+
+ // Hint the install function to read from a block map file.
+ if (android::base::EndsWithIgnoreCase(path, ".map")) {
+ path = "@" + path;
+ }
+
+ ui->Print("\n-- Install %s ...\n", path.c_str());
+ SetSdcardUpdateBootloaderMessage();
+
+ auto result = InstallWithFuseFromPath(path, ui);
+ ensure_path_unmounted(SDCARD_ROOT);
+ return result;
+}