1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
#!/usr/bin/env python3
# Copyright (c) 2014 Wladimir J. van der Laan
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
'''
A script to check that the (Linux) executables produced by gitian only contain
allowed gcc, glibc and libstdc++ version symbols. This makes sure they are
still compatible with the minimum supported Linux distribution versions.
Example usage:
find ../gitian-builder/build -type f -executable | xargs python contrib/devtools/symbol-check.py
'''
import subprocess
import re
import sys
import os
# Debian 6.0.9 (Squeeze) has:
#
# - g++ version 4.4.5 (https://packages.debian.org/search?suite=default§ion=all&arch=any&searchon=names&keywords=g%2B%2B)
# - libc version 2.11.3 (https://packages.debian.org/search?suite=default§ion=all&arch=any&searchon=names&keywords=libc6)
# - libstdc++ version 4.4.5 (https://packages.debian.org/search?suite=default§ion=all&arch=any&searchon=names&keywords=libstdc%2B%2B6)
#
# Ubuntu 10.04.4 (Lucid Lynx) has:
#
# - g++ version 4.4.3 (http://packages.ubuntu.com/search?keywords=g%2B%2B&searchon=names&suite=lucid§ion=all)
# - libc version 2.11.1 (http://packages.ubuntu.com/search?keywords=libc6&searchon=names&suite=lucid§ion=all)
# - libstdc++ version 4.4.3 (http://packages.ubuntu.com/search?suite=lucid§ion=all&arch=any&keywords=libstdc%2B%2B&searchon=names)
#
# Taking the minimum of these as our target.
#
# According to GNU ABI document (http://gcc.gnu.org/onlinedocs/libstdc++/manual/abi.html) this corresponds to:
# GCC 4.4.0: GCC_4.4.0
# GCC 4.4.2: GLIBCXX_3.4.13, CXXABI_1.3.3
# (glibc) GLIBC_2_11
#
MAX_VERSIONS = {
'GCC': (4,4,0),
'CXXABI': (1,3,3),
'GLIBCXX': (3,4,13),
'GLIBC': (2,11)
}
# See here for a description of _IO_stdin_used:
# https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=634261#109
# Ignore symbols that are exported as part of every executable
IGNORE_EXPORTS = {
b'_edata', b'_end', b'_init', b'__bss_start', b'_fini', b'_IO_stdin_used'
}
READELF_CMD = os.getenv('READELF', '/usr/bin/readelf')
CPPFILT_CMD = os.getenv('CPPFILT', '/usr/bin/c++filt')
# Allowed NEEDED libraries
ALLOWED_LIBRARIES = {
# bitcoind and bitcoin-qt
b'libgcc_s.so.1', # GCC base support
b'libc.so.6', # C library
b'libpthread.so.0', # threading
b'libanl.so.1', # DNS resolve
b'libm.so.6', # math library
b'librt.so.1', # real-time (clock)
b'ld-linux-x86-64.so.2', # 64-bit dynamic linker
b'ld-linux.so.2', # 32-bit dynamic linker
# bitcoin-qt only
b'libX11-xcb.so.1', # part of X11
b'libX11.so.6', # part of X11
b'libxcb.so.1', # part of X11
b'libfontconfig.so.1', # font support
b'libfreetype.so.6', # font parsing
b'libdl.so.2' # programming interface to dynamic linker
}
class CPPFilt(object):
'''
Demangle C++ symbol names.
Use a pipe to the 'c++filt' command.
'''
def __init__(self):
self.proc = subprocess.Popen(CPPFILT_CMD, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
def __call__(self, mangled):
self.proc.stdin.write(mangled + b'\n')
self.proc.stdin.flush()
return self.proc.stdout.readline().rstrip()
def close(self):
self.proc.stdin.close()
self.proc.stdout.close()
self.proc.wait()
def read_symbols(executable, imports=True):
'''
Parse an ELF executable and return a list of (symbol,version) tuples
for dynamic, imported symbols.
'''
p = subprocess.Popen([READELF_CMD, '--dyn-syms', '-W', executable], stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
(stdout, stderr) = p.communicate()
if p.returncode:
raise IOError('Could not read symbols for %s: %s' % (executable, stderr.strip()))
syms = []
for line in stdout.split(b'\n'):
line = line.split()
if len(line)>7 and re.match(b'[0-9]+:$', line[0]):
(sym, _, version) = line[7].partition(b'@')
is_import = line[6] == b'UND'
if version.startswith(b'@'):
version = version[1:]
if is_import == imports:
syms.append((sym, version))
return syms
def check_version(max_versions, version):
if b'_' in version:
(lib, _, ver) = version.rpartition(b'_')
else:
lib = version
ver = '0'
ver = tuple([int(x) for x in ver.split(b'.')])
if not lib in max_versions:
return False
return ver <= max_versions[lib]
def read_libraries(filename):
p = subprocess.Popen([READELF_CMD, '-d', '-W', filename], stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
(stdout, stderr) = p.communicate()
if p.returncode:
raise IOError('Error opening file')
libraries = []
for line in stdout.split(b'\n'):
tokens = line.split()
if len(tokens)>2 and tokens[1] == b'(NEEDED)':
match = re.match(b'^Shared library: \[(.*)\]$', b' '.join(tokens[2:]))
if match:
libraries.append(match.group(1))
else:
raise ValueError('Unparseable (NEEDED) specification')
return libraries
if __name__ == '__main__':
cppfilt = CPPFilt()
retval = 0
for filename in sys.argv[1:]:
# Check imported symbols
for sym,version in read_symbols(filename, True):
if version and not check_version(MAX_VERSIONS, version):
print('%s: symbol %s from unsupported version %s' % (filename, cppfilt(sym).decode('utf-8'), version.decode('utf-8')))
retval = 1
# Check exported symbols
for sym,version in read_symbols(filename, False):
if sym in IGNORE_EXPORTS:
continue
print('%s: export of symbol %s not allowed' % (filename, cppfilt(sym).decode('utf-8')))
retval = 1
# Check dependency libraries
for library_name in read_libraries(filename):
if library_name not in ALLOWED_LIBRARIES:
print('%s: NEEDED library %s is not allowed' % (filename, library_name.decode('utf-8')))
retval = 1
sys.exit(retval)
|
