# Copyright 2023 Oliver Smith # SPDX-License-Identifier: GPL-3.0-or-later import os from pmb.helpers import logging from pathlib import Path from pmb.core.types import PmbArgs import pmb.helpers.run import pmb.chroot.root import pmb.chroot.user import pmb.chroot.other import pmb.chroot.apk from pmb.core import Chroot def is_dtb(path): if not os.path.isfile(path): return False with open(path, 'rb') as f: # Check FDT magic identifier (0xd00dfeed) return f.read(4) == b'\xd0\x0d\xfe\xed' def get_mtk_label(path): """ Read the label from the MediaTek header of the kernel or ramdisk inside an extracted boot.img. :param path: to either the kernel or ramdisk extracted from boot.img :returns: * None: file does not exist or does not have MediaTek header * Label string (e.g. "ROOTFS", "KERNEL") """ if not os.path.exists(path): return None with open(path, 'rb') as f: # Check Mediatek header (0x88168858) if not f.read(4) == b'\x88\x16\x88\x58': return None f.seek(8) label = f.read(32).decode("utf-8").rstrip('\0') if label == "RECOVERY": logging.warning( "WARNING: This boot.img has MediaTek headers. Since you passed a" " recovery image instead of a regular boot.img, we can't tell what" " the ramdisk signature label is supposed to be, so we assume that" " it's the most common value, ROOTFS. There is a chance that this" " is wrong and it may not boot; in that case, run bootimg_analyze" " again with a regular boot.img. If this *is* a regular boot.img," " replace the value of deviceinfo_bootimg_mtk_label_ramdisk with" " 'RECOVERY'.") return "ROOTFS" else: return label def get_qcdt_type(path): """ Get the dt.img type by reading the first four bytes of the file. :param path: to the qcdt image extracted from boot.img :returns: * None: dt.img is of unknown type * Type string (e.g. "qcom", "sprd", "exynos") """ if not os.path.exists(path): return None with open(path, 'rb') as f: fourcc = f.read(4) if fourcc == b'QCDT': return "qcom" elif fourcc == b'SPRD': return "sprd" elif fourcc == b'DTBH': return "exynos" else: return None def bootimg(args: PmbArgs, path: Path): if not path.exists(): raise RuntimeError(f"Could not find file '{path}'") logging.info("NOTE: You will be prompted for your sudo/doas password, so" " we can set up a chroot to extract and analyze your" " boot.img file") pmb.chroot.apk.install(args, ["file", "unpackbootimg"], Chroot.native()) temp_path = pmb.chroot.other.tempfolder(args, Path("/tmp/bootimg_parser")) bootimg_path = Chroot.native() / temp_path / "boot.img" # Copy the boot.img into the chroot temporary folder # and make it world readable pmb.helpers.run.root(args, ["cp", path, bootimg_path]) pmb.helpers.run.root(args, ["chmod", "a+r", bootimg_path]) file_output = pmb.chroot.user(args, ["file", "-b", "boot.img"], working_dir=temp_path, output_return=True).rstrip() if "android bootimg" not in file_output.lower(): if "force" in args and args.force: logging.warning("WARNING: boot.img file seems to be invalid, but" " proceeding anyway (-f specified)") else: logging.info("NOTE: If you are sure that your file is a valid" " boot.img file, you could force the analysis" f" with: 'pmbootstrap bootimg_analyze {path} -f'") if ("linux kernel" in file_output.lower() or "ARM OpenFirmware FORTH Dictionary" in file_output): raise RuntimeError("File is a Kernel image, you might need the" " 'heimdall-isorec' flash method. See also:" " ") else: raise RuntimeError("File is not an Android boot.img. (" + file_output + ")") # Extract all the files pmb.chroot.user(args, ["unpackbootimg", "-i", "boot.img"], working_dir=temp_path) output = {} header_version = 0 # Get base, offsets, pagesize, cmdline and qcdt info # This file does not exist for example for qcdt images if os.path.isfile(f"{bootimg_path}-header_version"): with open(f"{bootimg_path}-header_version", 'r') as f: header_version = int(f.read().replace('\n', '')) output["header_version"] = str(header_version) if header_version >= 3: output["pagesize"] = "4096" else: with open(f"{bootimg_path}-base", 'r') as f: output["base"] = ("0x%08x" % int(f.read().replace('\n', ''), 16)) with open(f"{bootimg_path}-kernel_offset", 'r') as f: output["kernel_offset"] = ("0x%08x" % int(f.read().replace('\n', ''), 16)) with open(f"{bootimg_path}-ramdisk_offset", 'r') as f: output["ramdisk_offset"] = ("0x%08x" % int(f.read().replace('\n', ''), 16)) with open(f"{bootimg_path}-second_offset", 'r') as f: output["second_offset"] = ("0x%08x" % int(f.read().replace('\n', ''), 16)) with open(f"{bootimg_path}-tags_offset", 'r') as f: output["tags_offset"] = ("0x%08x" % int(f.read().replace('\n', ''), 16)) with open(f"{bootimg_path}-pagesize", 'r') as f: output["pagesize"] = f.read().replace('\n', '') if header_version == 2: with open(f"{bootimg_path}-dtb_offset", 'r') as f: output["dtb_offset"] = ("0x%08x" % int(f.read().replace('\n', ''), 16)) if get_mtk_label(f"{bootimg_path}-kernel") is not None: output["mtk_label_kernel"] = get_mtk_label(f"{bootimg_path}-kernel") if get_mtk_label(f"{bootimg_path}-ramdisk") is not None: output["mtk_label_ramdisk"] = get_mtk_label(f"{bootimg_path}-ramdisk") output["qcdt"] = ("true" if os.path.isfile(f"{bootimg_path}-dt") and os.path.getsize(f"{bootimg_path}-dt") > 0 else "false") if get_qcdt_type(f"{bootimg_path}-dt") is not None: output["qcdt_type"] = get_qcdt_type(f"{bootimg_path}-dt") output["dtb_second"] = ("true" if is_dtb(f"{bootimg_path}-second") else "false") with open(f"{bootimg_path}-cmdline", 'r') as f: output["cmdline"] = f.read().replace('\n', '') # Cleanup pmb.chroot.root(args, ["rm", "-r", temp_path]) return output