fix cipher props fetching for OpenSSL versions supporting SSLv2

[tls-check.git] / tls-check

diff --git a/tls-check b/tls-check
index 27651d53855b9a36b970c52434143898eb4a3126..84ca0094df53a911e9a739d536b388fcb958282d 100755 (executable)
--- a/tls-check
+++ b/tls-check
@@ -3,7 +3,9 @@ import subprocess, sys, argparse, time, re
 from collections import OrderedDict, namedtuple
 from enum import Enum
 
 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:
 def terminal_size():
     import fcntl, termios, struct
     try:


@@ -24,7 +26,6 @@ def compute_frac(fracs):
     return frac
 
 def print_progress(state, 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
     w, h = terminal_size()
     if w < STATE_WIDTH+10: return # not a (wide enough) terminal
     bar_width = w-STATE_WIDTH-3


@@ -35,14 +36,26 @@ def finish_progress():
     w, h = terminal_size()
     sys.stdout.write('\r'+(' '*w)+'\r')
     sys.stdout.flush()
     w, h = terminal_size()
     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(spec="ALL:COMPLEMENTOFALL"):
     ciphers = subprocess.check_output(["openssl", "ciphers", spec]).decode('UTF-8').strip()
     return ciphers.split(':')
 
 
 # cipher check
 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
     try:
         if cipher is not None:
             options = ["-cipher", cipher]+options


@@ -54,15 +67,13 @@ def test_cipher(host, port, protocol, cipher = None, options=[]):
         return True
 
 def test_protocol(host, port, protocol, ciphers, base_frac, wait_time=0, options=[]):
         return True
 
 def test_protocol(host, port, protocol, ciphers, base_frac, wait_time=0, options=[]):

-    if test_cipher(host, port, protocol, options=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))])
         # 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)
-            # throttle
-            time.sleep(wait_time/1000)
+            results[cipher] = test_cipher(host, port, protocol, cipher=cipher, wait_time=wait_time, options=options)

         return results
     else:
         # it is not supported
         return results
     else:
         # it is not supported


@@ -86,6 +97,17 @@ class CipherStrength(Enum):
     low = 1
     medium = 2
     high = 3
     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:
 CipherProps = namedtuple('CipherProps', 'bits, strength, isPfs')
 
 class CipherPropsProvider:


@@ -96,28 +118,32 @@ class CipherPropsProvider:
         self.high = set(list_ciphers("HIGH"))
         self.props = {}
     
         self.high = set(list_ciphers("HIGH"))
         self.props = {}
     

-    def __getProps(self, cipher):
+    def getProps(self, protocol, cipher):

         # as OpenSSL about this cipher
         # as OpenSSL about this cipher

-        cipherInfo = subprocess.check_output(["openssl", "ciphers", "-v", cipher]).decode('UTF-8').strip()
-        assert '\n' not in cipherInfo
+        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
         cipherInfoFields = cipherInfo.split()
         # get # of bits

-        bitMatch = re.match(r'^Enc=[0-9A-Za-z]+\(([0-9]+)\)$', cipherInfoFields[4])
-        if bitMatch is None:
+        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]))
             raise Exception("Unexpected OpenSSL output: Cannot determine encryption strength from {1}\nComplete output: {0}".format(cipherInfo, cipherInfoFields[4]))

-        bits = int(bitMatch.group(1))
+        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
         # figure out whether the cipher is pfs

-        kxMatch = re.match(r'^Kx=([0-9A-Z/]+)$', cipherInfoFields[2])
+        kxMatch = re.match(r'^Kx=([0-9A-Z/()]+)$', cipherInfoFields[2])

         if kxMatch is None:
         if kxMatch is None:

-            raise Exception("Unexpected OpenSSL output: Cannot determine key-exchange method from {1}\nComplete output: {0}".format(cipherInfo), cipherInfoFields[2])
+            raise Exception("Unexpected OpenSSL output: Cannot determine key-exchange method from {1}\nComplete output: {0}".format(cipherInfo, cipherInfoFields[2]))

         kx = kxMatch.group(1)
         kx = kxMatch.group(1)

-        isPfs = kx in ('DH', 'ECDH')
+        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
         # 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 is more than one from EXP, LOW, MEDIUM, 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:
         if isExp:
             strength = CipherStrength.exp
         elif isLow:


@@ -130,19 +156,12 @@ class CipherPropsProvider:
             strength = CipherStrength.unknown
         # done!
         return CipherProps(bits=bits, strength=strength, isPfs=isPfs)
             strength = CipherStrength.unknown
         # done!
         return CipherProps(bits=bits, strength=strength, isPfs=isPfs)

-    
-    def getProps(self, cipher):
-        if cipher in self.props:
-            return self.props[cipher]
-        props = self.__getProps(cipher)
-        self.props[cipher] = props
-        return props

 
 # main program
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description='Check TLS ciphers supported by a host')
     parser.add_argument("--starttls", dest="starttls",
 
 # 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]',
     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]',


@@ -174,6 +193,8 @@ if __name__ == "__main__":
         else:
             for cipher, supported in ciphers.items():
                 if supported:
         else:
             for cipher, supported in ciphers.items():
                 if supported:

-                    cipherProps = propsProvider.getProps(cipher)
-                    print("    {0} ({1}, {2} bits, {3})".format(cipher, cipherProps.strength.name, cipherProps.bits, "FS" if cipherProps.isPfs else "not FS"))
+                    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()
         print()