X-Git-Url: https://git.ralfj.de/tls-check.git/blobdiff_plain/ac0e7156a0d16de49f07c4d56c988c52393e2ecc..079098709ef1c3019ec809aab120c8af8cca266a:/tls-check?ds=inline diff --git a/tls-check b/tls-check index 9d84f42..04c911f 100755 --- a/tls-check +++ b/tls-check @@ -1,9 +1,11 @@ -#!/usr/bin/python3 -import subprocess, sys, argparse -from collections import OrderedDict +#!/usr/bin/env python3 +import subprocess, sys, argparse, time, re +from collections import OrderedDict, namedtuple from enum import Enum -# progress bar +# progress bar and other console output fun +STATE_WIDTH = 30 + def terminal_size(): import fcntl, termios, struct try: @@ -24,7 +26,6 @@ def compute_frac(fracs): return frac def print_progress(state, fracs): - STATE_WIDTH = 30 w, h = terminal_size() if w < STATE_WIDTH+10: return # not a (wide enough) terminal bar_width = w-STATE_WIDTH-3 @@ -36,50 +37,137 @@ def finish_progress(): sys.stdout.write('\r'+(' '*w)+'\r') sys.stdout.flush() +class ConsoleFormat: + BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = range(8) + RESET_SEQ = "\033[0m" + COLOR_SEQ = "\033[1;3%dm" + BOLD_SEQ = "\033[1m" + + @staticmethod + def color(text, color): + return (ConsoleFormat.COLOR_SEQ % color) + text + ConsoleFormat.RESET_SEQ + + # cipher check -def list_ciphers(): - ciphers = subprocess.check_output(["openssl", "ciphers", "ALL:COMPLEMENTOFALL"]).decode('UTF-8').strip() +def list_ciphers(spec="ALL:COMPLEMENTOFALL"): + ciphers = subprocess.check_output(["openssl", "ciphers", spec]).decode('UTF-8').strip() return ciphers.split(':') -def test_cipher(host, port, protocol, cipher = None, options=[]): +def test_cipher(host, port, protocol, cipher = None, wait_time=0, options=[]): + # throttle + time.sleep(wait_time/1000) try: if cipher is not None: options = ["-cipher", cipher]+options - subprocess.check_call(["openssl", "s_client", "-"+protocol, "-connect", host+":"+str(port)]+options, + subprocess.check_call(["openssl", "s_client", "-"+protocol, "-connect", host+":"+str(port), "-servername", host]+options, stdin=subprocess.DEVNULL, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL) except subprocess.CalledProcessError: return False else: return True -def test_protocol(host, port, protocol, ciphers, base_frac, options=[]): - if test_cipher(host, port, protocol, options=options): +def test_protocol(host, port, protocol, ciphers, base_frac, wait_time=0, options=[]): + if test_cipher(host, port, protocol, wait_time=wait_time, options=options): # the protocol is supported results = OrderedDict() for i in range(len(ciphers)): cipher = ciphers[i] print_progress(protocol+" "+cipher, base_frac+[(i, len(ciphers))]) - results[cipher] = test_cipher(host, port, protocol, cipher, options) + results[cipher] = test_cipher(host, port, protocol, cipher=cipher, wait_time=wait_time, options=options) return results else: # it is not supported return None -def test_host(host, port, options=[]): +def test_host(host, port, wait_time=0, options=[]): ciphers = list_ciphers() results = OrderedDict() protocols = ('ssl2', 'ssl3', 'tls1', 'tls1_1', 'tls1_2') for i in range(len(protocols)): protocol = protocols[i] print_progress(protocol, [(i, len(protocols))]) - results[protocol] = test_protocol(host, port, protocol, ciphers, [(i, len(protocols))], options) + results[protocol] = test_protocol(host, port, protocol, ciphers, [(i, len(protocols))], wait_time, options) finish_progress() return results +# cipher classification +class CipherStrength(Enum): + unknown = -1 + exp = 0 + low = 1 + medium = 2 + high = 3 + + def colorName(self): + if self == CipherStrength.unknown: + return self.name + elif self.value == CipherStrength.high.value: + return ConsoleFormat.color(self.name, ConsoleFormat.GREEN) + elif self.value == CipherStrength.medium.value: + return ConsoleFormat.color(self.name, ConsoleFormat.YELLOW) + else: + return ConsoleFormat.color(self.name, ConsoleFormat.RED) + +CipherProps = namedtuple('CipherProps', 'bits, strength, isPfs') + +class CipherPropsProvider: + def __init__(self): + self.exp = set(list_ciphers("EXP")) + self.low = set(list_ciphers("LOW")) + self.medium = set(list_ciphers("MEDIUM")) + self.high = set(list_ciphers("HIGH")) + self.props = {} + + def getProps(self, protocol, cipher): + # strip the sub-version-number from the protocol + pos = protocol.find('_') + if pos >= 0: + protocol = protocol[:pos] + # as OpenSSL about this cipher + cipherInfo = subprocess.check_output(["openssl", "ciphers", "-v", "-"+protocol, cipher]).decode('UTF-8').strip() + assert '\n' not in cipherInfo, "Cipher "+cipher+" produced unexpected output:\n"+cipherInfo + cipherInfoFields = cipherInfo.split() + # get # of bits + encMatch = re.match(r'^Enc=([0-9A-Za-z]+)\(([0-9]+)\)$', cipherInfoFields[4]) + if encMatch is None: + raise Exception("Unexpected OpenSSL output: Cannot determine encryption strength from {1}\nComplete output: {0}".format(cipherInfo, cipherInfoFields[4])) + encCipher = encMatch.group(1) + bits = int(encMatch.group(2)) + if encCipher == '3DES': + # OpenSSL gives the key size, which however for 3DES is a totally bad estimate + bits = int(bits*2/3) + # figure out whether the cipher is pfs + kxMatch = re.match(r'^Kx=([0-9A-Z/()]+)$', cipherInfoFields[2]) + if kxMatch is None: + raise Exception("Unexpected OpenSSL output: Cannot determine key-exchange method from {1}\nComplete output: {0}".format(cipherInfo, cipherInfoFields[2])) + kx = kxMatch.group(1) + isPfs = kx in ('DH', 'DH(512)', 'ECDH') + # determine security level + isExp = cipher in self.exp + isLow = cipher in self.low + isMedium = cipher in self.medium + isHigh = cipher in self.high + assert isExp+isLow+isMedium+isHigh <= 1, "Cipher "+cipher+" is more than one from EXP, LOW, MEDIUM, HIGH" + if isExp: + strength = CipherStrength.exp + elif isLow: + strength = CipherStrength.low + elif isMedium: + strength = CipherStrength.medium + elif isHigh: + strength = CipherStrength.high + else: + strength = CipherStrength.unknown + # done! + return CipherProps(bits=bits, strength=strength, isPfs=isPfs) + +# main program if __name__ == "__main__": parser = argparse.ArgumentParser(description='Check TLS ciphers supported by a host') parser.add_argument("--starttls", dest="starttls", - help="Use a STARTTLS variant to establish the TLS connection. Possible values include smpt, imap, xmpp.") + help="Use a STARTTLS variant to establish the TLS connection. Possible values include smtp, imap.") + parser.add_argument("--wait-time", "-t", dest="wait_time", default="10", + help="Time (in ms) to wait between two connections to the server. Default is 10ms.") parser.add_argument("host", metavar='HOST[:PORT]', help="The host to check") args = parser.parse_args() @@ -91,15 +179,17 @@ if __name__ == "__main__": host = args.host port = 443 - # get options + # get options and other stuff + wait_time = float(args.wait_time) options = [] if args.starttls is not None: options += ['-starttls', args.starttls] # run the test - results = test_host(host, port, options) + results = test_host(host, port, wait_time, options) # print the results + propsProvider = CipherPropsProvider() for protocol, ciphers in results.items(): print(protocol+":") if ciphers is None: @@ -107,5 +197,8 @@ if __name__ == "__main__": else: for cipher, supported in ciphers.items(): if supported: - print(" "+cipher) + cipherProps = propsProvider.getProps(protocol, cipher) + fsText = ConsoleFormat.color("FS", ConsoleFormat.GREEN) if cipherProps.isPfs else ConsoleFormat.color("no FS", ConsoleFormat.RED) + bitColor = ConsoleFormat.GREEN if cipherProps.bits >= 128 else (ConsoleFormat.YELLOW if cipherProps.bits >= 100 else ConsoleFormat.RED) + print(" {0} ({1}, {2}, {3})".format(cipher.ljust(STATE_WIDTH), cipherProps.strength.colorName(), ConsoleFormat.color(str(cipherProps.bits)+" bits", bitColor), fsText)) print()