summaryrefslogtreecommitdiffstats
path: root/bootloader.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'bootloader.cpp')
-rw-r--r--bootloader.cpp235
1 files changed, 235 insertions, 0 deletions
diff --git a/bootloader.cpp b/bootloader.cpp
new file mode 100644
index 000000000..f6c0e9341
--- /dev/null
+++ b/bootloader.cpp
@@ -0,0 +1,235 @@
+/*
+ * Copyright (C) 2008 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 <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <fs_mgr.h>
+
+#include <android-base/file.h>
+
+#include "bootloader.h"
+#include "common.h"
+#include "mtdutils/mtdutils.h"
+#include "roots.h"
+#include "unique_fd.h"
+
+static int get_bootloader_message_mtd(bootloader_message* out, const Volume* v);
+static int set_bootloader_message_mtd(const bootloader_message* in, const Volume* v);
+static bool read_misc_partition(const Volume* v, size_t offset, size_t size, std::string* out);
+static bool write_misc_partition(const Volume* v, size_t offset, const std::string& in);
+
+int get_bootloader_message(bootloader_message* out) {
+ Volume* v = volume_for_path("/misc");
+ if (v == nullptr) {
+ LOGE("Cannot load volume /misc!\n");
+ return -1;
+ }
+ if (strcmp(v->fs_type, "mtd") == 0) {
+ return get_bootloader_message_mtd(out, v);
+ } else if (strcmp(v->fs_type, "emmc") == 0) {
+ std::string s;
+ if (!read_misc_partition(v, BOOTLOADER_MESSAGE_OFFSET_IN_MISC, sizeof(bootloader_message),
+ &s)) {
+ return -1;
+ }
+ memcpy(out, s.data(), s.size());
+ return 0;
+ }
+ LOGE("Unknown misc partition fs_type \"%s\"\n", v->fs_type);
+ return -1;
+}
+
+bool read_wipe_package(size_t size, std::string* out) {
+ Volume* v = volume_for_path("/misc");
+ if (v == nullptr) {
+ LOGE("Cannot load volume /misc!\n");
+ return false;
+ }
+ if (strcmp(v->fs_type, "mtd") == 0) {
+ LOGE("Read wipe package on mtd is not supported.\n");
+ return false;
+ } else if (strcmp(v->fs_type, "emmc") == 0) {
+ return read_misc_partition(v, WIPE_PACKAGE_OFFSET_IN_MISC, size, out);
+ }
+ LOGE("Unknown misc partition fs_type \"%s\"\n", v->fs_type);
+ return false;
+}
+
+int set_bootloader_message(const bootloader_message* in) {
+ Volume* v = volume_for_path("/misc");
+ if (v == nullptr) {
+ LOGE("Cannot load volume /misc!\n");
+ return -1;
+ }
+ if (strcmp(v->fs_type, "mtd") == 0) {
+ return set_bootloader_message_mtd(in, v);
+ } else if (strcmp(v->fs_type, "emmc") == 0) {
+ std::string s(reinterpret_cast<const char*>(in), sizeof(*in));
+ bool success = write_misc_partition(v, BOOTLOADER_MESSAGE_OFFSET_IN_MISC, s);
+ return success ? 0 : -1;
+ }
+ LOGE("Unknown misc partition fs_type \"%s\"\n", v->fs_type);
+ return -1;
+}
+
+// ------------------------------
+// for misc partitions on MTD
+// ------------------------------
+
+static const int MISC_PAGES = 3; // number of pages to save
+static const int MISC_COMMAND_PAGE = 1; // bootloader command is this page
+
+static int get_bootloader_message_mtd(bootloader_message* out,
+ const Volume* v) {
+ size_t write_size;
+ mtd_scan_partitions();
+ const MtdPartition* part = mtd_find_partition_by_name(v->blk_device);
+ if (part == nullptr || mtd_partition_info(part, nullptr, nullptr, &write_size)) {
+ LOGE("failed to find \"%s\"\n", v->blk_device);
+ return -1;
+ }
+
+ MtdReadContext* read = mtd_read_partition(part);
+ if (read == nullptr) {
+ LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
+ return -1;
+ }
+
+ const ssize_t size = write_size * MISC_PAGES;
+ char data[size];
+ ssize_t r = mtd_read_data(read, data, size);
+ if (r != size) LOGE("failed to read \"%s\": %s\n", v->blk_device, strerror(errno));
+ mtd_read_close(read);
+ if (r != size) return -1;
+
+ memcpy(out, &data[write_size * MISC_COMMAND_PAGE], sizeof(*out));
+ return 0;
+}
+static int set_bootloader_message_mtd(const bootloader_message* in,
+ const Volume* v) {
+ size_t write_size;
+ mtd_scan_partitions();
+ const MtdPartition* part = mtd_find_partition_by_name(v->blk_device);
+ if (part == nullptr || mtd_partition_info(part, nullptr, nullptr, &write_size)) {
+ LOGE("failed to find \"%s\"\n", v->blk_device);
+ return -1;
+ }
+
+ MtdReadContext* read = mtd_read_partition(part);
+ if (read == nullptr) {
+ LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
+ return -1;
+ }
+
+ ssize_t size = write_size * MISC_PAGES;
+ char data[size];
+ ssize_t r = mtd_read_data(read, data, size);
+ if (r != size) LOGE("failed to read \"%s\": %s\n", v->blk_device, strerror(errno));
+ mtd_read_close(read);
+ if (r != size) return -1;
+
+ memcpy(&data[write_size * MISC_COMMAND_PAGE], in, sizeof(*in));
+
+ MtdWriteContext* write = mtd_write_partition(part);
+ if (write == nullptr) {
+ LOGE("failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
+ return -1;
+ }
+ if (mtd_write_data(write, data, size) != size) {
+ LOGE("failed to write \"%s\": %s\n", v->blk_device, strerror(errno));
+ mtd_write_close(write);
+ return -1;
+ }
+ if (mtd_write_close(write)) {
+ LOGE("failed to finish \"%s\": %s\n", v->blk_device, strerror(errno));
+ return -1;
+ }
+
+ LOGI("Set boot command \"%s\"\n", in->command[0] != 255 ? in->command : "");
+ return 0;
+}
+
+
+// ------------------------------------
+// for misc partitions on block devices
+// ------------------------------------
+
+static void wait_for_device(const char* fn) {
+ int tries = 0;
+ int ret;
+ do {
+ ++tries;
+ struct stat buf;
+ ret = stat(fn, &buf);
+ if (ret == -1) {
+ printf("failed to stat \"%s\" try %d: %s\n", fn, tries, strerror(errno));
+ sleep(1);
+ }
+ } while (ret && tries < 10);
+
+ if (ret) {
+ printf("failed to stat \"%s\"\n", fn);
+ }
+}
+
+static bool read_misc_partition(const Volume* v, size_t offset, size_t size, std::string* out) {
+ wait_for_device(v->blk_device);
+ unique_fd fd(open(v->blk_device, O_RDONLY));
+ if (fd.get() == -1) {
+ LOGE("Failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
+ return false;
+ }
+ if (lseek(fd.get(), static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) {
+ LOGE("Failed to lseek \"%s\": %s\n", v->blk_device, strerror(errno));
+ return false;
+ }
+ out->resize(size);
+ if (!android::base::ReadFully(fd.get(), &(*out)[0], size)) {
+ LOGE("Failed to read \"%s\": %s\n", v->blk_device, strerror(errno));
+ return false;
+ }
+ return true;
+}
+
+static bool write_misc_partition(const Volume* v, size_t offset, const std::string& in) {
+ wait_for_device(v->blk_device);
+ unique_fd fd(open(v->blk_device, O_WRONLY | O_SYNC));
+ if (fd.get() == -1) {
+ LOGE("Failed to open \"%s\": %s\n", v->blk_device, strerror(errno));
+ return false;
+ }
+ if (lseek(fd.get(), static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) {
+ LOGE("Failed to lseek \"%s\": %s\n", v->blk_device, strerror(errno));
+ return false;
+ }
+ if (!android::base::WriteFully(fd.get(), in.data(), in.size())) {
+ LOGE("Failed to write \"%s\": %s\n", v->blk_device, strerror(errno));
+ return false;
+ }
+
+ if (fsync(fd.get()) == -1) {
+ LOGE("Failed to fsync \"%s\": %s\n", v->blk_device, strerror(errno));
+ return false;
+ }
+ return true;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-02 03:10:10 +0200