# Copyright 2013-2016 The Meson development team
# 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.
import sys
import os
import stat
import struct
import shutil
import subprocess
import typing as T
from ..mesonlib import OrderedSet, generate_list, Popen_safe
SHT_STRTAB = 3
DT_NEEDED = 1
DT_RPATH = 15
DT_RUNPATH = 29
DT_STRTAB = 5
DT_SONAME = 14
DT_MIPS_RLD_MAP_REL = 1879048245
# Global cache for tools
INSTALL_NAME_TOOL = False
class DataSizes:
def __init__(self, ptrsize: int, is_le: bool) -> None:
if is_le:
p = '<'
else:
p = '>'
self.Half = p + 'h'
self.HalfSize = 2
self.Word = p + 'I'
self.WordSize = 4
self.Sword = p + 'i'
self.SwordSize = 4
if ptrsize == 64:
self.Addr = p + 'Q'
self.AddrSize = 8
self.Off = p + 'Q'
self.OffSize = 8
self.XWord = p + 'Q'
self.XWordSize = 8
self.Sxword = p + 'q'
self.SxwordSize = 8
else:
self.Addr = p + 'I'
self.AddrSize = 4
self.Off = p + 'I'
self.OffSize = 4
class DynamicEntry(DataSizes):
def __init__(self, ifile: T.BinaryIO, ptrsize: int, is_le: bool) -> None:
super().__init__(ptrsize, is_le)
self.ptrsize = ptrsize
if ptrsize == 64:
self.d_tag = struct.unpack(self.Sxword, ifile.read(self.SxwordSize))[0]
self.val = struct.unpack(self.XWord, ifile.read(self.XWordSize))[0]
else:
self.d_tag = struct.unpack(self.Sword, ifile.read(self.SwordSize))[0]
self.val = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
def write(self, ofile: T.BinaryIO) -> None:
if self.ptrsize == 64:
ofile.write(struct.pack(self.Sxword, self.d_tag))
ofile.write(struct.pack(self.XWord, self.val))
else:
ofile.write(struct.pack(self.Sword, self.d_tag))
ofile.write(struct.pack(self.Word, self.val))
class SectionHeader(DataSizes):
def __init__(self, ifile: T.BinaryIO, ptrsize: int, is_le: bool) -> None:
super().__init__(ptrsize, is_le)
is_64 = ptrsize == 64
# Elf64_Word
self.sh_name = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
# Elf64_Word
self.sh_type = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
# Elf64_Xword
if is_64:
self.sh_flags = struct.unpack(self.XWord, ifile.read(self.XWordSize))[0]
else:
self.sh_flags = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
# Elf64_Addr
self.sh_addr = struct.unpack(self.Addr, ifile.read(self.AddrSize))[0]
# Elf64_Off
self.sh_offset = struct.unpack(self.Off, ifile.read(self.OffSize))[0]
# Elf64_Xword
if is_64:
self.sh_size = struct.unpack(self.XWord, ifile.read(self.XWordSize))[0]
else:
self.sh_size = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
# Elf64_Word
self.sh_link = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
# Elf64_Word
self.sh_info = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
# Elf64_Xword
if is_64:
self.sh_addralign = struct.unpack(self.XWord, ifile.read(self.XWordSize))[0]
else:
self.sh_addralign = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
# Elf64_Xword
if is_64:
self.sh_entsize = struct.unpack(self.XWord, ifile.read(self.XWordSize))[0]
else:
self.sh_entsize = struct.unpack(self.Word, ifile.read(self.WordSize))[0]
class Elf(DataSizes):
def __init__(self, bfile: str, verbose: bool = True) -> None:
self.bfile = bfile
self.verbose = verbose
self.sections = [] # type: T.List[SectionHeader]
self.dynamic = [] # type: T.List[DynamicEntry]
self.open_bf(bfile)
try:
(self.ptrsize, self.is_le) = self.detect_elf_type()
super().__init__(self.ptrsize, self.is_le)
self.parse_header()
self.parse_sections()
self.parse_dynamic()
except (struct.error, RuntimeError):
self.close_bf()
raise
def open_bf(self, bfile: str) -> None:
self.bf = None
self.bf_perms = None
try:
self.bf = open(bfile, 'r+b')
except PermissionError as e:
self.bf_perms = stat.S_IMODE(os.lstat(bfile).st_mode)
os.chmod(bfile, stat.S_IREAD | stat.S_IWRITE | stat.S_IEXEC)
try:
self.bf = open(bfile, 'r+b')
except Exception:
os.chmod(bfile, self.bf_perms)
self.bf_perms = None
raise e
def close_bf(self) -> None:
if self.bf is not None:
if self.bf_perms is not None:
os.fchmod(self.bf.fileno(), self.bf_perms)
self.bf_perms = None
self.bf.close()
self.bf = None
def __enter__(self) -> 'Elf':
return self
def __del__(self) -> None:
self.close_bf()
def __exit__(self, exc_type: T.Any, exc_value: T.Any, traceback: T.Any) -> None:
self.close_bf()
def detect_elf_type(self) -> T.Tuple[int, bool]:
data = self.bf.read(6)
if data[1:4] != b'ELF':
# This script gets called to non-elf targets too
# so just ignore them.
if self.verbose:
print(f'File {self.bfile!r} is not an ELF file.')
sys.exit(0)
if data[4] == 1:
ptrsize = 32
elif data[4] == 2:
ptrsize = 64
else:
sys.exit(f'File {self.bfile!r} has unknown ELF class.')
if data[5] == 1:
is_le = True
elif data[5] == 2:
is_le = False
else:
sys.exit(f'File {self.bfile!r} has unknown ELF endianness.')
return ptrsize, is_le
def parse_header(self) -> None:
self.bf.seek(0)
self.e_ident = struct.unpack('16s', self.bf.read(16))[0]
self.e_type = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
self.e_machine = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
self.e_version = struct.unpack(self.Word, self.bf.read(self.WordSize))[0]
self.e_entry = struct.unpack(self.Addr, self.bf.read(self.AddrSize))[0]
self.e_phoff = struct.unpack(self.Off, self.bf.read(self.OffSize))[0]
self.e_shoff = struct.unpack(self.Off, self.bf.read(self.OffSize))[0]
self.e_flags = struct.unpack(self.Word, self.bf.read(self.WordSize))[0]
self.e_ehsize = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
self.e_phentsize = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
self.e_phnum = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
self.e_shentsize = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
self.e_shnum = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
self.e_shstrndx = struct.unpack(self.Half, self.bf.read(self.HalfSize))[0]
def parse_sections(self) -> None:
self.bf.seek(self.e_shoff)
for _ in range(self.e_shnum):
self.sections.append(SectionHeader(self.bf, self.ptrsize, self.is_le))
def read_str(self) -> bytes:
arr = []
x = self.bf.read(1)
while x != b'\0':
arr.append(x)
x = self.bf.read(1)
if x == b'':
raise RuntimeError('Tried to read past the end of the file')
return b''.join(arr)
def find_section(self, target_name: bytes) -> T.Optional[SectionHeader]:
section_names = self.sections[self.e_shstrndx]
for i in self.sections:
self.bf.seek(section_names.sh_offset + i.sh_name)
name = self.read_str()
if name == target_name:
return i
return None
def parse_dynamic(self) -> None:
sec = self.find_section(b'.dynamic')
if sec is None:
return
self.bf.seek(sec.sh_offset)
while True:
e = DynamicEntry(self.bf, self.ptrsize, self.is_le)
self.dynamic.append(e)
if e.d_tag == 0:
break
@generate_list
def get_section_names(self) -> T.Generator[str, None, None]:
section_names = self.sections[self.e_shstrndx]
for i in self.sections:
self.bf.seek(section_names.sh_offset + i.sh_name)
yield self.read_str().decode()
def get_soname(self) -> T.Optional[str]:
soname = None
strtab = None
for i in self.dynamic:
if i.d_tag == DT_SONAME:
soname = i
if i.d_tag == DT_STRTAB:
strtab = i
if soname is None or strtab is None:
return None
self.bf.seek(strtab.val + soname.val)
return self.read_str().decode()
def get_entry_offset(self, entrynum: int) -> T.Optional[int]:
sec = self.find_section(b'.dynstr')
for i in self.dynamic:
if i.d_tag == entrynum:
res = sec.sh_offset + i.val
assert isinstance(res, int)
return res
return None
def get_rpath(self) -> T.Optional[str]:
offset = self.get_entry_offset(DT_RPATH)
if offset is None:
return None
self.bf.seek(offset)
return self.read_str().decode()
def get_runpath(self) -> T.Optional[str]:
offset = self.get_entry_offset(DT_RUNPATH)
if offset is None:
return None
self.bf.seek(offset)
return self.read_str().decode()
@generate_list
def get_deps(self) -> T.Generator[str, None, None]:
sec = self.find_section(b'.dynstr')
for i in self.dynamic:
if i.d_tag == DT_NEEDED:
offset = sec.sh_offset + i.val
self.bf.seek(offset)
yield self.read_str().decode()
def fix_deps(self, prefix: bytes) -> None:
sec = self.find_section(b'.dynstr')
deps = []
for i in self.dynamic:
if i.d_tag == DT_NEEDED:
deps.append(i)
for i in deps:
offset = sec.sh_offset + i.val
self.bf.seek(offset)
name = self.read_str()
if name.startswith(prefix):
basename = name.rsplit(b'/', maxsplit=1)[-1]
padding = b'\0' * (len(name) - len(basename))
newname = basename + padding
assert len(newname) == len(name)
self.bf.seek(offset)
self.bf.write(newname)
def fix_rpath(self, fname: str, rpath_dirs_to_remove: T.Set[bytes], new_rpath: bytes) -> None:
# The path to search for can be either rpath or runpath.
# Fix both of them to be sure.
self.fix_rpathtype_entry(fname, rpath_dirs_to_remove, new_rpath, DT_RPATH)
self.fix_rpathtype_entry(fname, rpath_dirs_to_remove, new_rpath, DT_RUNPATH)
def fix_rpathtype_entry(self, fname: str, rpath_dirs_to_remove: T.Set[bytes], new_rpath: bytes, entrynum: int) -> None:
rp_off = self.get_entry_offset(entrynum)
if rp_off is None:
if self.verbose:
print(f'File {fname!r} does not have an rpath. It should be a fully static executable.')
return
self.bf.seek(rp_off)
old_rpath = self.read_str()
# Some rpath entries may come from multiple sources.
# Only add each one once.
new_rpaths = OrderedSet() # type: OrderedSet[bytes]
if new_rpath:
new_rpaths.update(new_rpath.split(b':'))
if old_rpath:
# Filter out build-only rpath entries
# added by get_link_dep_subdirs() or
# specified by user with build_rpath.
for rpath_dir in old_rpath.split(b':'):
if not (rpath_dir in rpath_dirs_to_remove or
rpath_dir == (b'X' * len(rpath_dir))):
if rpath_dir:
new_rpaths.add(rpath_dir)
# Prepend user-specified new entries while preserving the ones that came from pkgconfig etc.
new_rpath = b':'.join(new_rpaths)
if len(old_rpath) < len(new_rpath):
msg = "New rpath must not be longer than the old one.\n Old: {}\n New: {}".format(old_rpath.decode('utf-8'), new_rpath.decode('utf-8'))
sys.exit(msg)
# The linker does read-only string deduplication. If there is a
# string that shares a suffix with the rpath, they might get
# dedupped. This means changing the rpath string might break something
# completely unrelated. This has already happened once with X.org.
# Thus we want to keep this change as small as possible to minimize
# the chance of obliterating other strings. It might still happen
# but our behavior is identical to what chrpath does and it has
# been in use for ages so based on that this should be rare.
if not new_rpath:
self.remove_rpath_entry(entrynum)
else:
self.bf.seek(rp_off)
self.bf.write(new_rpath)
self.bf.write(b'\0')
def remove_rpath_entry(self, entrynum: int) -> None:
sec = self.find_section(b'.dynamic')
if sec is None:
return None
for (i, entry) in enumerate(self.dynamic):
if entry.d_tag == entrynum:
rpentry = self.dynamic[i]
rpentry.d_tag = 0
self.dynamic = self.dynamic[:i] + self.dynamic[i + 1:] + [rpentry]
break
# DT_MIPS_RLD_MAP_REL is relative to the offset of the tag. Adjust it consequently.
for entry in self.dynamic[i:]:
if entry.d_tag == DT_MIPS_RLD_MAP_REL:
entry.val += 2 * (self.ptrsize // 8)
break
self.bf.seek(sec.sh_offset)
for entry in self.dynamic:
entry.write(self.bf)
return None
def fix_elf(fname: str, rpath_dirs_to_remove: T.Set[bytes], new_rpath: T.Optional[bytes], verbose: bool = True) -> None:
if new_rpath is not None:
with Elf(fname, verbose) as e:
# note: e.get_rpath() and e.get_runpath() may be useful
e.fix_rpath(fname, rpath_dirs_to_remove, new_rpath)
def get_darwin_rpaths_to_remove(fname: str) -> T.List[str]:
p, out, _ = Popen_safe(['otool', '-l', fname], stderr=subprocess.DEVNULL)
if p.returncode != 0:
raise subprocess.CalledProcessError(p.returncode, p.args, out)
result = []
current_cmd = 'FOOBAR'
for line in out.split('\n'):
line = line.strip()
if ' ' not in line:
continue
key, value = line.strip().split(' ', 1)
if key == 'cmd':
current_cmd = value
if key == 'path' and current_cmd == 'LC_RPATH':
rp = value.split('(', 1)[0].strip()
result.append(rp)
return result
def fix_darwin(fname: str, new_rpath: str, final_path: str, install_name_mappings: T.Dict[str, str]) -> None:
try:
rpaths = get_darwin_rpaths_to_remove(fname)
except subprocess.CalledProcessError:
# Otool failed, which happens when invoked on a
# non-executable target. Just return.
return
try:
args = []
if rpaths:
# TODO: fix this properly, not totally clear how
#
# removing rpaths from binaries on macOS has tons of
# weird edge cases. For instance, if the user provided
# a '-Wl,-rpath' argument in LDFLAGS that happens to
# coincide with an rpath generated from a dependency,
# this would cause installation failures, as meson would
# generate install_name_tool calls with two identical
# '-delete_rpath' arguments, which install_name_tool
# fails on. Because meson itself ensures that it never
# adds duplicate rpaths, duplicate rpaths necessarily
# come from user variables. The idea of using OrderedSet
# is to remove *at most one* duplicate RPATH entry. This
# is not optimal, as it only respects the user's choice
# partially: if they provided a non-duplicate '-Wl,-rpath'
# argument, it gets removed, if they provided a duplicate
# one, it remains in the final binary. A potentially optimal
# solution would split all user '-Wl,-rpath' arguments from
# LDFLAGS, and later add them back with '-add_rpath'.
for rp in OrderedSet(rpaths):
args += ['-delete_rpath', rp]
subprocess.check_call(['install_name_tool', fname] + args,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL)
args = []
if new_rpath:
args += ['-add_rpath', new_rpath]
# Rewrite -install_name @rpath/libfoo.dylib to /path/to/libfoo.dylib
if fname.endswith('dylib'):
args += ['-id', final_path]
if install_name_mappings:
for old, new in install_name_mappings.items():
args += ['-change', old, new]
if args:
subprocess.check_call(['install_name_tool', fname] + args,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL)
except Exception as err:
raise SystemExit(err)
def fix_jar(fname: str) -> None:
subprocess.check_call(['jar', 'xfv', fname, 'META-INF/MANIFEST.MF'])
with open('META-INF/MANIFEST.MF', 'r+', encoding='utf-8') as f:
lines = f.readlines()
f.seek(0)
for line in lines:
if not line.startswith('Class-Path:'):
f.write(line)
f.truncate()
subprocess.check_call(['jar', 'ufm', fname, 'META-INF/MANIFEST.MF'])
def fix_rpath(fname: str, rpath_dirs_to_remove: T.Set[bytes], new_rpath: T.Union[str, bytes], final_path: str, install_name_mappings: T.Dict[str, str], verbose: bool = True) -> None:
global INSTALL_NAME_TOOL # pylint: disable=global-statement
# Static libraries, import libraries, debug information, headers, etc
# never have rpaths
# DLLs and EXE currently do not need runtime path fixing
if fname.endswith(('.a', '.lib', '.pdb', '.h', '.hpp', '.dll', '.exe')):
return
try:
if fname.endswith('.jar'):
fix_jar(fname)
return
if isinstance(new_rpath, str):
new_rpath = new_rpath.encode('utf8')
fix_elf(fname, rpath_dirs_to_remove, new_rpath, verbose)
return
except SystemExit as e:
if isinstance(e.code, int) and e.code == 0:
pass
else:
raise
# We don't look for this on import because it will do a useless PATH lookup
# on non-mac platforms. That can be expensive on some Windows machines
# (up to 30ms), which is significant with --only-changed. For details, see:
# https://github.com/mesonbuild/meson/pull/6612#discussion_r378581401
if INSTALL_NAME_TOOL is False:
INSTALL_NAME_TOOL = bool(shutil.which('install_name_tool'))
if INSTALL_NAME_TOOL:
if isinstance(new_rpath, bytes):
new_rpath = new_rpath.decode('utf8')
fix_darwin(fname, new_rpath, final_path, install_name_mappings)