/usr/bin/openssl-vulnkey is in openssl-blacklist 0.5-3.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 | #!/usr/bin/python
#
# openssl-vulnkey: check a database of sha1'd static key hashes for
# known vulnerable keys
# Copyright (C) 2008-2011 Canonical Ltd.
# Author: Jamie Strandboge <jamie@canonical.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3,
# as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
from optparse import OptionParser
import os
import re
import hashlib
import subprocess
import sys
import tempfile
import shutil
version = "0.5-3"
db_prefix = "/usr/share/openssl-blacklist/blacklist.RSA-"
db_lines = []
parser = OptionParser(usage="%prog FILE [FILE]", \
version="%prog: " + version, \
description="This program checks if FILEs are known " + \
"vulnerable static keys")
parser.add_option("-q", "--quiet", action="store_true", dest="quiet", \
help="be quiet")
parser.add_option("-b", "--bits", dest="bits", \
help="number of bits (requires -m)")
parser.add_option("-m", "--modulus", dest="modulus", \
help="modulus to check (requires -b)")
(options, args) = parser.parse_args()
if not ((options.modulus and options.bits) or args):
parser.print_help()
sys.exit(1)
def cmd(command, input = None, stderr = subprocess.PIPE, stdout = subprocess.PIPE, stdin = None):
'''Try to execute given command (array) and return its stdout, or return
a textual error if it failed.'''
try:
sp = subprocess.Popen(command, stdin=stdin, stdout=stdout, stderr=stderr, close_fds=True)
except OSError, e:
return [127, str(e)]
out = sp.communicate(input)[0]
return [sp.returncode,out]
def get_contents(file):
'''Determine the type of certificate it is. Returns empty string if
unsupported.'''
args = ['-modulus', '-text', '-in', file]
rc, report = cmd(['openssl', 'rsa'] + args)
if rc == 0:
return ("rsa", report)
rc, report = cmd(['openssl', 'x509'] + args)
if rc == 0:
return ("x509", report)
rc, report = cmd(['openssl', 'req'] + args)
if rc == 0:
return ("req", report)
return ("", report)
def get_bits(contents, type):
'''Find bit length of file. Returns empty string if unsupported.'''
for line in contents:
leading = "Private-Key: "
if type == "x509" or type == "req":
leading = "RSA Public Key: "
if leading not in contents:
# OpenSSL 1.0.0
leading = "Public-Key: "
# TODO: don't hardcode these
if leading + "(512" in contents:
return "512"
elif leading + "(1024" in contents:
return "1024"
elif leading + "(2048" in contents:
return "2048"
elif leading + "(4096" in contents:
return "4096"
elif leading + "(8192" in contents:
return "8192"
return ""
def get_modulus(contents):
'''Find modulus of file'''
for line in contents.split('\n'):
if re.match(r'^Modulus=', line):
return line + '\n'
return ""
def get_exponent(contents):
'''Find exponent of file. Returns empty string if unsupported.'''
if "Exponent: 65537 " in contents:
return "65537"
return ""
def check_db(bits, last, modulus, name=""):
'''Check modulus against database'''
global db_lines
if last != bits:
db = db_prefix + bits
# Read in the database
try:
fh = open(db, 'r')
except:
try:
print >> sys.stderr, "WARN: could not open database for %s " \
"bits. Skipped %s" % (bits, name)
except IOError:
pass
return False
db_lines = fh.read().split('\n')
fh.close()
key = hashlib.sha1(modulus).hexdigest()
#print "bits: %s\nmodulus: %s\nkey: %s\nkey80: %s" % (bits, modulus, key, key[20:])
if key[20:] in db_lines:
if not options.quiet:
print "COMPROMISED: %s %s" % (key, name)
return True
else:
if not options.quiet:
print "Not blacklisted: %s %s" % (key, name)
return False
last_bits = ""
found = False
error = False
if options.bits and options.modulus:
found = check_db(options.bits, last_bits, \
"Modulus=%s\n" % (options.modulus))
else:
# Check each file
for f in args:
realname = f
if f == "-":
# dump stdin to tmpfile, operate on tmpfile instead
temp = tempfile.NamedTemporaryFile()
shutil.copyfileobj(sys.stdin,temp)
temp.flush()
f = temp.name
try:
file(f).read()
except IOError, e:
if not options.quiet:
print >> sys.stderr, "ERROR: %s: %s" % (realname, e.strerror)
error = True
continue
(type, contents) = get_contents(f)
if type == "":
if not options.quiet:
print >> sys.stderr, "Skipped: '%s' is unsupported type " + \
"(not x509, req or rsa)" % (realname)
continue
exp = get_exponent(contents)
if exp == "":
if not options.quiet:
print >> sys.stderr, "Skipped: '%s' has unsupported exponent" % \
(realname)
continue
bits = get_bits(contents, type)
if bits == "":
if not options.quiet:
print >> sys.stderr, "Skipped: '%s' has unsupported bit size" % \
(realname)
continue
modulus = get_modulus(contents)
if modulus == "":
if not options.quiet:
print >> sys.stderr, "ERROR: %s: problem finding modulus" % \
(realname)
error = True
continue
if check_db(bits, last_bits, modulus, realname):
found = True
last_bits = bits
if found:
sys.exit(1)
elif error:
sys.exit(2)
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