| #!/usr/bin/env fuchsia-vendored-python |
| # Copyright 2017 The Fuchsia Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| from __future__ import print_function |
| |
| from contextlib import contextmanager |
| from collections import namedtuple |
| import argparse |
| import json |
| import mmap |
| import os |
| import struct |
| import sys |
| import uuid |
| |
| # Standard ELF constants. |
| ELFMAG = b"\x7fELF" |
| EI_CLASS = 4 |
| ELFCLASS32 = 1 |
| ELFCLASS64 = 2 |
| EI_DATA = 5 |
| ELFDATA2LSB = 1 |
| ELFDATA2MSB = 2 |
| ET_EXEC = 2 |
| ET_DYN = 3 |
| EM_386 = 3 |
| EM_ARM = 40 |
| EM_X86_64 = 62 |
| EM_AARCH64 = 183 |
| PT_LOAD = 1 |
| PT_DYNAMIC = 2 |
| PT_INTERP = 3 |
| PT_NOTE = 4 |
| PT_GNU_RELRO = 0x6474E552 |
| PF_X = 1 |
| PF_W = 2 |
| PF_R = 4 |
| DT_NEEDED = 1 |
| DT_PLTRELSZ = 2 |
| DT_STRTAB = 5 |
| DT_RELA = 7 |
| DT_RELASZ = 8 |
| DT_REL = 17 |
| DT_RELSZ = 18 |
| DT_RELRSZ = 35 |
| DT_RELR = 36 |
| DT_PLTREL = 20 |
| DT_SONAME = 14 |
| DT_RELACOUNT = 0x6FFFFFF9 |
| DT_RELCOUNT = 0x6FFFFFFA |
| NT_GNU_BUILD_ID = 3 |
| SHT_SYMTAB = 2 |
| SHF_ALLOC = 2 |
| |
| IS_PYTHON3 = sys.version_info[0] >= 3 |
| |
| |
| class elf_note( |
| namedtuple( |
| "elf_note", |
| [ |
| "name", |
| "type", |
| "desc", |
| ], |
| ) |
| ): |
| # An ELF note is identified by (name_string, type_integer). |
| def ident(self): |
| return (self.name, self.type) |
| |
| def is_build_id(self): |
| return self.ident() == ("GNU\0", NT_GNU_BUILD_ID) |
| |
| def build_id_hex(self): |
| if self.is_build_id(): |
| return "".join(("%02x" % byte) for byte in self.desc) |
| return None |
| |
| def __repr__(self): |
| return "elf_note(%r, %#x, <%d bytes>)" % ( |
| self.name, |
| self.type, |
| len(self.desc), |
| ) |
| |
| |
| def gen_elf(): |
| # { 'Struct1': (ELFCLASS32 fields, ELFCLASS64 fields), |
| # 'Struct2': fields_same_for_both, ... } |
| elf_types = { |
| "Ehdr": ( |
| [ |
| ("e_ident", "16s"), |
| ("e_type", "H"), |
| ("e_machine", "H"), |
| ("e_version", "I"), |
| ("e_entry", "I"), |
| ("e_phoff", "I"), |
| ("e_shoff", "I"), |
| ("e_flags", "I"), |
| ("e_ehsize", "H"), |
| ("e_phentsize", "H"), |
| ("e_phnum", "H"), |
| ("e_shentsize", "H"), |
| ("e_shnum", "H"), |
| ("e_shstrndx", "H"), |
| ], |
| [ |
| ("e_ident", "16s"), |
| ("e_type", "H"), |
| ("e_machine", "H"), |
| ("e_version", "I"), |
| ("e_entry", "Q"), |
| ("e_phoff", "Q"), |
| ("e_shoff", "Q"), |
| ("e_flags", "I"), |
| ("e_ehsize", "H"), |
| ("e_phentsize", "H"), |
| ("e_phnum", "H"), |
| ("e_shentsize", "H"), |
| ("e_shnum", "H"), |
| ("e_shstrndx", "H"), |
| ], |
| ), |
| "Phdr": ( |
| [ |
| ("p_type", "I"), |
| ("p_offset", "I"), |
| ("p_vaddr", "I"), |
| ("p_paddr", "I"), |
| ("p_filesz", "I"), |
| ("p_memsz", "I"), |
| ("p_flags", "I"), |
| ("p_align", "I"), |
| ], |
| [ |
| ("p_type", "I"), |
| ("p_flags", "I"), |
| ("p_offset", "Q"), |
| ("p_vaddr", "Q"), |
| ("p_paddr", "Q"), |
| ("p_filesz", "Q"), |
| ("p_memsz", "Q"), |
| ("p_align", "Q"), |
| ], |
| ), |
| "Shdr": ( |
| [ |
| ("sh_name", "L"), |
| ("sh_type", "L"), |
| ("sh_flags", "L"), |
| ("sh_addr", "L"), |
| ("sh_offset", "L"), |
| ("sh_size", "L"), |
| ("sh_link", "L"), |
| ("sh_info", "L"), |
| ("sh_addralign", "L"), |
| ("sh_entsize", "L"), |
| ], |
| [ |
| ("sh_name", "L"), |
| ("sh_type", "L"), |
| ("sh_flags", "Q"), |
| ("sh_addr", "Q"), |
| ("sh_offset", "Q"), |
| ("sh_size", "Q"), |
| ("sh_link", "L"), |
| ("sh_info", "L"), |
| ("sh_addralign", "Q"), |
| ("sh_entsize", "Q"), |
| ], |
| ), |
| "Dyn": ( |
| [ |
| ("d_tag", "i"), |
| ("d_val", "I"), |
| ], |
| [ |
| ("d_tag", "q"), |
| ("d_val", "Q"), |
| ], |
| ), |
| "Nhdr": [ |
| ("n_namesz", "I"), |
| ("n_descsz", "I"), |
| ("n_type", "I"), |
| ], |
| "dwarf2_line_header": [ |
| ("unit_length", "L"), |
| ("version", "H"), |
| ("header_length", "L"), |
| ("minimum_instruction_length", "B"), |
| ("default_is_stmt", "B"), |
| ("line_base", "b"), |
| ("line_range", "B"), |
| ("opcode_base", "B"), |
| ], |
| "dwarf4_line_header": [ |
| ("unit_length", "L"), |
| ("version", "H"), |
| ("header_length", "L"), |
| ("minimum_instruction_length", "B"), |
| ("maximum_operations_per_instruction", "B"), |
| ("default_is_stmt", "B"), |
| ("line_base", "b"), |
| ("line_range", "b"), |
| ("opcode_base", "B"), |
| ], |
| } |
| |
| # There is an accessor for each struct, e.g. Ehdr. |
| # Ehdr.read is a function like Struct.unpack_from. |
| # Ehdr.size is the size of the struct. |
| elf_accessor = namedtuple("elf_accessor", ["size", "read", "write", "pack"]) |
| |
| # All the accessors for a format (class, byte-order) form one elf, |
| # e.g. use elf.Ehdr and elf.Phdr. |
| elf = namedtuple("elf", list(elf_types.keys())) |
| |
| def gen_accessors(is64, struct_byte_order): |
| def make_accessor(type, decoder): |
| return elf_accessor( |
| size=decoder.size, |
| read=lambda buffer, offset=0: type._make( |
| decoder.unpack_from(buffer, offset) |
| ), |
| write=lambda buffer, offset, x: decoder.pack_into( |
| buffer, offset, *x |
| ), |
| pack=lambda x: decoder.pack(*x), |
| ) |
| |
| for name, fields in elf_types.items(): |
| if isinstance(fields, tuple): |
| fields = fields[1 if is64 else 0] |
| type = namedtuple(name, [field_name for field_name, fmt in fields]) |
| decoder = struct.Struct( |
| struct_byte_order + "".join(fmt for field_name, fmt in fields) |
| ) |
| yield make_accessor(type, decoder) |
| |
| for elfclass, is64 in [(ELFCLASS32, False), (ELFCLASS64, True)]: |
| for elf_bo, struct_bo in [(ELFDATA2LSB, "<"), (ELFDATA2MSB, ">")]: |
| yield ((elfclass, elf_bo), elf(*gen_accessors(is64, struct_bo))) |
| |
| |
| # e.g. ELF[file[EI_CLASS], file[EI_DATA]].Ehdr.read(file).e_phnum |
| ELF = dict(gen_elf()) |
| |
| |
| def get_elf_accessor(file): |
| # If it looks like an ELF file, whip out the decoder ring. |
| if file[: len(ELFMAG)] == ELFMAG: |
| return ELF.get( |
| ( |
| ord(file[EI_CLASS : EI_CLASS + 1]), |
| ord(file[EI_DATA : EI_DATA + 1]), |
| ), |
| None, |
| ) |
| return None |
| |
| |
| def gen_phdrs(file, elf, ehdr): |
| for pos in range(0, ehdr.e_phnum * elf.Phdr.size, elf.Phdr.size): |
| yield elf.Phdr.read(file, ehdr.e_phoff + pos) |
| |
| |
| def gen_shdrs(file, elf, ehdr): |
| for pos in range(0, ehdr.e_shnum * elf.Shdr.size, elf.Shdr.size): |
| yield elf.Shdr.read(file, ehdr.e_shoff + pos) |
| |
| |
| cpu = namedtuple( |
| "cpu", |
| [ |
| "e_machine", # ELF e_machine int |
| "llvm", # LLVM triple CPU component |
| "gn", # GN target_cpu |
| ], |
| ) |
| |
| ELF_MACHINE_TO_CPU = { |
| elf: cpu(elf, llvm, gn) |
| for elf, llvm, gn in [ |
| (EM_386, "i386", "x86"), |
| (EM_ARM, "arm", "arm"), |
| (EM_X86_64, "x86_64", "x64"), |
| (EM_AARCH64, "aarch64", "arm64"), |
| ] |
| } |
| |
| |
| @contextmanager |
| def mmapper(filename): |
| """A context manager that yields (fd, file_contents) given a file name. |
| This ensures that the mmap and file objects are closed at the end of the |
| 'with' statement.""" |
| fileobj = open(filename, "rb") |
| fd = fileobj.fileno() |
| size = os.fstat(fd).st_size |
| if size == 0: |
| # mmap can't handle empty files. |
| try: |
| yield fd, "", 0 |
| finally: |
| fileobj.close() |
| else: |
| mmapobj = mmap.mmap(fd, 0, access=mmap.ACCESS_READ) |
| try: |
| yield fd, mmapobj, size |
| finally: |
| mmapobj.close() |
| fileobj.close() |
| |
| |
| def makedirs(dirs): |
| try: |
| os.makedirs(dirs) |
| except OSError as e: |
| if e.errno != os.errno.EEXIST: |
| raise e |
| |
| |
| elf_sizes = namedtuple( |
| "elf_sizes", |
| [ |
| "file", # st_size |
| "memory", # lowest p_vaddr to highest p_memsz |
| "rel", # DT_RELSZ (+ DT_PLTRELSZ if matching) |
| "rela", # DT_RELASZ (+ DT_PLTRELSZ if matching) |
| "relr", # DT_RELRSZ |
| "relcount", # DT_RELCOUNT + DT_RELACOUNT |
| "relro", # PT_GNU_RELRO p_memsz |
| "code", # executable segment p_filesz |
| "rodata", # read-only data segment p_filesz |
| "data", # writable segment p_filesz |
| "bss", # writable segment p_memsz past p_filesz |
| ], |
| ) |
| |
| |
| # elf_info objects are only created by `get_elf_info` or the `copy` or |
| # `rename` methods. |
| class elf_info( |
| namedtuple( |
| "elf_info", |
| [ |
| "filename", |
| "sizes", # elf_sizes |
| "cpu", # cpu tuple |
| "notes", # list of (ident, desc): selected notes |
| "build_id", # string: lowercase hex |
| "stripped", # bool: Has no symbols or .debug_* sections |
| "interp", # string or None: PT_INTERP (without \0) |
| "soname", # string or None: DT_SONAME |
| "needed", # list of strings: DT_NEEDED |
| ], |
| ) |
| ): |
| def rename(self, filename): |
| assert os.path.samefile(self.filename, filename) |
| return self._replace(filename=filename) |
| |
| def with_soname(self, soname): |
| return self._replace(soname=soname) |
| |
| def copy(self): |
| return self._replace() |
| |
| def _replace(self, **kwargs): |
| # Copy the tuple. |
| clone = self.__class__(*super()._replace(**kwargs)) |
| # Copy the lazy state. |
| clone.elf = self.elf |
| if self.get_sources == clone.get_sources: |
| raise Exception("uninitialized elf_info object!") |
| clone.get_sources = self.get_sources |
| return clone |
| |
| # This is replaced with a closure by the creator in get_elf_info. |
| def get_sources(self): |
| raise Exception("uninitialized elf_info object!") |
| |
| def strip(self, stripped_filename): |
| """Write stripped output to the given file unless it already exists |
| with identical contents. Returns True iff the file was changed.""" |
| with mmapper(self.filename) as mapped: |
| fd, file, filesize = mapped |
| ehdr = self.elf.Ehdr.read(file) |
| |
| stripped_ehdr = ehdr._replace(e_shoff=0, e_shnum=0, e_shstrndx=0) |
| stripped_size = max( |
| phdr.p_offset + phdr.p_filesz |
| for phdr in gen_phdrs(file, self.elf, ehdr) |
| if phdr.p_type == PT_LOAD |
| ) |
| assert ( |
| ehdr.e_phoff + (ehdr.e_phnum * ehdr.e_phentsize) |
| <= stripped_size |
| ) |
| |
| def gen_stripped_contents(): |
| yield self.elf.Ehdr.pack(stripped_ehdr) |
| yield file[self.elf.Ehdr.size : stripped_size] |
| |
| def old_file_matches(): |
| old_size = os.path.getsize(stripped_filename) |
| new_size = sum(len(x) for x in gen_stripped_contents()) |
| if old_size != new_size: |
| return False |
| with open(stripped_filename, "rb") as f: |
| for chunk in gen_stripped_contents(): |
| if f.read(len(chunk)) != chunk: |
| return False |
| return True |
| |
| if os.path.exists(stripped_filename): |
| if old_file_matches(): |
| return False |
| else: |
| os.remove(stripped_filename) |
| # Create the new file with the same mode as the original. |
| with os.fdopen( |
| os.open( |
| stripped_filename, |
| os.O_WRONLY | os.O_CREAT | os.O_EXCL, |
| os.fstat(fd).st_mode & 0o777, |
| ), |
| "wb", |
| ) as stripped_file: |
| stripped_file.write(self.elf.Ehdr.pack(stripped_ehdr)) |
| stripped_file.write(file[self.elf.Ehdr.size : stripped_size]) |
| return True |
| |
| |
| def get_elf_info(filename, match_notes=False): |
| file = None |
| elf = None |
| ehdr = None |
| phdrs = None |
| |
| # Yields an elf_note for each note in any PT_NOTE segment. |
| def gen_notes(): |
| def round_up_to(size): |
| return ((size + 3) // 4) * 4 |
| |
| for phdr in phdrs: |
| if phdr.p_type == PT_NOTE: |
| pos = phdr.p_offset |
| while pos < phdr.p_offset + phdr.p_filesz: |
| nhdr = elf.Nhdr.read(file, pos) |
| pos += elf.Nhdr.size |
| # TODO(https://fxbug.dev/42132793) PT_NOTE is expected to be valid |
| # 7-bit ASCII or UTF-8. Remove this when clients no longer |
| # depend on that behavior. |
| name = str(file[pos : pos + nhdr.n_namesz].decode()) |
| pos += round_up_to(nhdr.n_namesz) |
| # PT_DESC is not always string-ish, just copy the bytes. |
| if IS_PYTHON3: |
| desc = file[pos : pos + nhdr.n_descsz] |
| else: |
| desc = [ord(b) for b in file[pos : pos + nhdr.n_descsz]] |
| pos += round_up_to(nhdr.n_descsz) |
| yield elf_note(name, nhdr.n_type, desc) |
| |
| def gen_sections(): |
| shdrs = list(gen_shdrs(file, elf, ehdr)) |
| if not shdrs: |
| return |
| strtab_shdr = shdrs[ehdr.e_shstrndx] |
| for shdr, i in zip(shdrs, range(len(shdrs))): |
| if i == 0: |
| continue |
| assert shdr.sh_name < strtab_shdr.sh_size, ( |
| "%s: invalid sh_name" % filename |
| ) |
| yield (shdr, extract_C_string(strtab_shdr.sh_offset + shdr.sh_name)) |
| |
| # Generates '\0'-terminated strings starting at the given offset, |
| # until an empty string. |
| def gen_strings(start): |
| while True: |
| end = file.find(b"\0", start) |
| assert end >= start, "%s: Unterminated string at %#x" % ( |
| filename, |
| start, |
| ) |
| if start == end: |
| break |
| yield file[start:end].decode() |
| start = end + 1 |
| |
| def extract_C_string(start): |
| for string in gen_strings(start): |
| return string |
| return "" |
| |
| # Returns a string of hex digits (or None). |
| def get_build_id(): |
| build_id = None |
| for note in gen_notes(): |
| # Note that the last build_id note needs to be used due to https://fxbug.dev/42101443. |
| possible_build_id = note.build_id_hex() |
| if possible_build_id: |
| build_id = possible_build_id |
| return build_id |
| |
| # Returns a list of elf_note objects. |
| def get_matching_notes(): |
| if isinstance(match_notes, bool): |
| if match_notes: |
| return list(gen_notes()) |
| else: |
| return [] |
| # If not a bool, it's an iterable of ident pairs. |
| return [note for note in gen_notes() if note.ident() in match_notes] |
| |
| # Returns a string (without trailing '\0'), or None. |
| def get_interp(): |
| # PT_INTERP points directly to a string in the file. |
| for interp in (phdr for phdr in phdrs if phdr.p_type == PT_INTERP): |
| interp = file[interp.p_offset : interp.p_offset + interp.p_filesz] |
| if interp[-1:] == b"\0": |
| interp = interp[:-1] |
| return interp.decode() |
| return None |
| |
| def get_dynamic(): |
| # PT_DYNAMIC points to the list of ElfNN_Dyn tags. |
| for dynamic in (phdr for phdr in phdrs if phdr.p_type == PT_DYNAMIC): |
| return [ |
| elf.Dyn.read(file, dynamic.p_offset + dyn_offset) |
| for dyn_offset in range(0, dynamic.p_filesz, elf.Dyn.size) |
| ] |
| return None |
| |
| def dyn_get(dyn, tag): |
| for dt in dyn: |
| if dt.d_tag == tag: |
| return dt.d_val |
| return None |
| |
| # Returns a string (or None) and a set of strings. |
| def get_soname_and_needed(dyn): |
| # Each DT_NEEDED or DT_SONAME points to a string in the .dynstr table. |
| def GenDTStrings(tag): |
| return ( |
| extract_C_string(strtab_offset + dt.d_val) |
| for dt in dyn |
| if dt.d_tag == tag |
| ) |
| |
| if dyn is None: |
| return None, set() |
| |
| # DT_STRTAB points to the string table's vaddr (.dynstr). |
| strtab_vaddr = dyn_get(dyn, DT_STRTAB) |
| |
| # Find the PT_LOAD containing the vaddr to compute the file offset. |
| [strtab_offset] = [ |
| strtab_vaddr - phdr.p_vaddr + phdr.p_offset |
| for phdr in phdrs |
| if ( |
| phdr.p_type == PT_LOAD |
| and phdr.p_vaddr <= strtab_vaddr |
| and strtab_vaddr - phdr.p_vaddr < phdr.p_filesz |
| ) |
| ] |
| |
| soname = None |
| for soname in GenDTStrings(DT_SONAME): |
| break |
| |
| return soname, set(GenDTStrings(DT_NEEDED)) |
| |
| def get_stripped(): |
| return all( |
| (shdr.sh_flags & SHF_ALLOC) != 0 |
| or (shdr.sh_type != SHT_SYMTAB and not name.startswith(".debug_")) |
| for shdr, name in gen_sections() |
| ) |
| |
| def get_memory_size(): |
| segments = [phdr for phdr in phdrs if phdr.p_type == PT_LOAD] |
| first = segments[0] |
| last = segments[-1] |
| start = first.p_vaddr & -first.p_align |
| last = (last.p_vaddr + last.p_memsz + last.p_align - 1) & -last.p_align |
| return last - start |
| |
| def get_relro_size(): |
| return sum( |
| phdr.p_memsz for phdr in phdrs if phdr.p_type == PT_GNU_RELRO |
| ) |
| |
| def get_segment_size(phdr, file, mem): |
| start = phdr.p_vaddr & -phdr.p_align |
| file_end = phdr.p_vaddr + phdr.p_filesz |
| mem_end = phdr.p_vaddr + phdr.p_memsz |
| file_end = (file_end + phdr.p_align - 1) & -phdr.p_align |
| mem_end = (mem_end + phdr.p_align - 1) & -phdr.p_align |
| if file and mem: |
| return mem_end - start |
| if file: |
| return file_end - start |
| return mem_end - file_end |
| |
| def gen_executable_segments(): |
| return ( |
| phdr |
| for phdr in phdrs |
| if phdr.p_type == PT_LOAD and (phdr.p_flags & PF_X) != 0 |
| ) |
| |
| def gen_writable_segments(): |
| return ( |
| phdr |
| for phdr in phdrs |
| if phdr.p_type == PT_LOAD and (phdr.p_flags & PF_W) != 0 |
| ) |
| |
| def gen_rodata_segments(): |
| return ( |
| phdr |
| for phdr in phdrs |
| if phdr.p_type == PT_LOAD and phdr.p_flags == PF_R |
| ) |
| |
| def get_code_size(): |
| return sum( |
| get_segment_size(phdr, file=True, mem=False) |
| for phdr in gen_executable_segments() |
| ) |
| |
| def get_rodata_size(): |
| return sum( |
| get_segment_size(phdr, file=True, mem=False) |
| for phdr in gen_rodata_segments() |
| ) |
| |
| def get_data_size(): |
| return sum( |
| get_segment_size(phdr, file=True, mem=False) |
| for phdr in gen_writable_segments() |
| ) |
| |
| def get_bss_size(): |
| return sum( |
| get_segment_size(phdr, file=False, mem=True) |
| for phdr in gen_writable_segments() |
| ) |
| |
| def get_relsz(dyn, tag, sizetag): |
| if dyn is None: |
| return 0 |
| relsz = dyn_get(dyn, sizetag) |
| if relsz is None: |
| relsz = 0 |
| if dyn_get(dyn, DT_PLTREL) == tag: |
| pltrelsz = dyn_get(dyn, DT_PLTRELSZ) |
| if pltrelsz is not None: |
| relsz += pltrelsz |
| return relsz |
| |
| def get_relcount(dyn): |
| if dyn is None: |
| return 0 |
| return (dyn_get(dyn, DT_RELCOUNT) or 0) + ( |
| dyn_get(dyn, DT_RELACOUNT) or 0 |
| ) |
| |
| def get_cpu(): |
| return ELF_MACHINE_TO_CPU.get(ehdr.e_machine) |
| |
| def gen_source_files(): |
| # Given the file position of a CU header (starting with the |
| # beginning of the .debug_line section), return the position |
| # of the include_directories portion and the position of the |
| # next CU header. |
| def read_line_header(pos): |
| # Decode DWARF .debug_line per-CU header. |
| hdr_type = elf.dwarf2_line_header |
| hdr = hdr_type.read(file, pos) |
| assert hdr.unit_length < 0xFFFFFFF0, "%s: 64-bit DWARF" % filename |
| assert hdr.version in [ |
| 2, |
| 3, |
| 4, |
| ], "%s: DWARF .debug_line version %r" % (filename, hdr.version) |
| if hdr.version == 4: |
| hdr_type = elf.dwarf4_line_header |
| hdr = hdr_type.read(file, pos) |
| return ( |
| pos + hdr_type.size + hdr.opcode_base - 1, |
| pos + 4 + hdr.unit_length, |
| ) |
| |
| # Decode include_directories portion of DWARF .debug_line format. |
| def read_include_dirs(pos): |
| include_dirs = list(gen_strings(pos)) |
| pos += sum(len(dir) + 1 for dir in include_dirs) + 1 |
| return pos, include_dirs |
| |
| # Decode file_paths portion of DWARF .debug_line format. |
| def gen_file_paths(start, limit): |
| while start < limit: |
| end = file.find(b"\0", start, limit) |
| assert end >= start, "%s: Unterminated string at %#x" % ( |
| filename, |
| start, |
| ) |
| if start == end: |
| break |
| name = file[start:end].decode() |
| start = end + 1 |
| # Decode 3 ULEB128s to advance start, but only use the first. |
| for i in range(3): |
| value = 0 |
| bits = 0 |
| while start < limit: |
| # TODO(https://fxbug.dev/42125859): Remove this single-element slice hack |
| # once Python2 is no longer used in-tree. |
| byte = ord(file[start : start + 1]) |
| start += 1 |
| value |= (byte & 0x7F) << bits |
| if (byte & 0x80) == 0: |
| break |
| bits += 7 |
| if i == 0: |
| include_idx = value |
| # Ignore the fake file names the compiler leaks into the DWARF. |
| if name not in ["<stdin>", "<command-line>"]: |
| yield name, include_idx |
| |
| for shdr, name in gen_sections(): |
| if name == ".debug_line": |
| next = shdr.sh_offset |
| while next < shdr.sh_offset + shdr.sh_size: |
| pos, next = read_line_header(next) |
| |
| pos, include_dirs = read_include_dirs(pos) |
| assert pos <= next |
| |
| # 0 means relative to DW_AT_comp_dir, which should be ".". |
| # Indices into the actual table start at 1. |
| include_dirs.insert(0, "") |
| |
| # Decode file_paths and apply include directories. |
| for name, i in gen_file_paths(pos, next): |
| name = os.path.join(include_dirs[i], name) |
| yield os.path.normpath(name) |
| |
| # This closure becomes the elf_info object's `get_sources` method. |
| def lazy_get_sources(): |
| # Run the generator and cache its results as a set. |
| sources_cache = set(gen_source_files()) |
| # Replace the method to just return the cached set next time. |
| info.get_sources = lambda: sources_cache |
| return sources_cache |
| |
| # Map in the whole file's contents and use it as a string. |
| with mmapper(filename) as mapped: |
| fd, file, filesize = mapped |
| elf = get_elf_accessor(file) |
| if elf is not None: |
| # ELF header leads to program headers. |
| ehdr = elf.Ehdr.read(file) |
| if ehdr.e_type not in (ET_EXEC, ET_DYN): |
| # This is an invalid file or an ET_REL file, which don't count |
| # as ELF files for our purposes. |
| return None |
| assert ( |
| ehdr.e_phentsize == elf.Phdr.size |
| ), "%s: invalid e_phentsize %s" % (filename, ehdr.e_phentsize) |
| phdrs = list(gen_phdrs(file, elf, ehdr)) |
| dyn = get_dynamic() |
| info = elf_info( |
| filename, |
| elf_sizes( |
| file=filesize, |
| memory=get_memory_size(), |
| code=get_code_size(), |
| rodata=get_rodata_size(), |
| relro=get_relro_size(), |
| data=get_data_size(), |
| bss=get_bss_size(), |
| rel=get_relsz(dyn, DT_REL, DT_RELSZ), |
| rela=get_relsz(dyn, DT_RELA, DT_RELASZ), |
| relr=get_relsz(dyn, DT_RELR, DT_RELRSZ), |
| relcount=get_relcount(dyn), |
| ), |
| get_cpu(), |
| get_matching_notes(), |
| get_build_id(), |
| get_stripped(), |
| get_interp(), |
| *get_soname_and_needed(dyn), |
| ) |
| info.elf = elf |
| info.get_sources = lazy_get_sources |
| return info |
| |
| return None |
| |
| |
| # Module public API. |
| __all__ = ["cpu", "elf_info", "elf_note", "get_elf_accessor", "get_elf_info"] |
| |
| |
| def main(): |
| parser = argparse.ArgumentParser() |
| parser.add_argument( |
| "--strip", |
| action="store_true", |
| help="Strip each file into FILE.ei-strip", |
| ) |
| parser.add_argument( |
| "--build-id", action="store_true", help="Print each build ID" |
| ) |
| parser.add_argument("--bootfs-dir", help="bootfs content", metavar="DIR") |
| parser.add_argument("--zbi", help="Read zbi.json", metavar="FILE") |
| parser.add_argument("--blobs", help="Read blobs.json", metavar="FILE") |
| parser.add_argument("--sizes", help="Write elf_sizes.json", metavar="FILE") |
| parser.add_argument("file", help="ELF file", metavar="FILE", nargs="*") |
| args = parser.parse_args() |
| |
| files = args.file |
| if args.zbi: |
| if not args.bootfs_dir: |
| parser.exit("--zbi and --bootfs-dir must be specified together") |
| bootfs_map = {} |
| with open(args.zbi) as f: |
| zbi = json.load(f) |
| for entry in zbi: |
| if entry["type"] != "BOOTFS": |
| continue |
| for item in entry["contents"]: |
| filepath = os.path.join(args.bootfs_dir, item["name"]) |
| files.append(filepath) |
| bootfs_map[filepath] = item |
| if args.blobs: |
| with open(args.blobs) as f: |
| blobs = json.load(f) |
| files += [blob["source_path"] for blob in blobs] |
| |
| if args.sizes: |
| if args.blobs: |
| blob_map = {blob["source_path"]: blob for blob in blobs} |
| |
| def json_size(info): |
| sizes = info.sizes._asdict() |
| sizes["path"] = info.filename |
| sizes["build_id"] = info.build_id |
| if args.zbi and info.filename in bootfs_map: |
| item = bootfs_map[info.filename] |
| assert ( |
| info.sizes.file == item["length"] |
| ), "%r != %r in %r vs %r" % ( |
| info.sizes.file, |
| blob["length"], |
| info, |
| blob, |
| ) |
| sizes["zbi"] = item["size"] |
| if args.blobs and info.filename in blob_map: |
| blob = blob_map[info.filename] |
| assert ( |
| info.sizes.file == blob["bytes"] |
| ), "%r != %r in %r vs %r" % ( |
| info.sizes.file, |
| blob["bytes"], |
| info, |
| blob, |
| ) |
| sizes["blob"] = blob["size"] |
| return sizes |
| |
| # Sort for stable output. |
| sizes = sorted( |
| [ |
| json_size(info) |
| for info in (get_elf_info(file) for file in files) |
| if info |
| ], |
| key=lambda info: info["path"], |
| ) |
| totals = {} |
| for file in sizes: |
| for key, val in file.items(): |
| if isinstance(val, int): |
| totals[key] = totals.get(key, 0) + val |
| with open(args.sizes, "w") as outf: |
| json.dump( |
| {"files": sizes, "totals": totals}, |
| outf, |
| sort_keys=True, |
| indent=1, |
| ) |
| else: |
| for file in files: |
| info = get_elf_info(file) |
| |
| if args.strip: |
| stripped_filename = info.filename + ".ei-strip" |
| info.strip(stripped_filename) |
| print(stripped_filename) |
| elif args.build_id: |
| print(info.build_id) |
| else: |
| print(info) |
| for source in info.get_sources(): |
| print("\t" + source) |
| |
| return 0 |
| |
| |
| if __name__ == "__main__": |
| sys.exit(main()) |
