Merge branch 'master' into simplify_extension

scripts/tls.py

@@ -11,6 +11,7 @@
 import os
 import os.path
 import socket
+import struct
 import time
 import getopt
 import binascii
@@ -484,6 +485,8 @@ def handshake(self, connection):
                 start = time.clock()
                 connection.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY,
                                       1)
+                connection.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER,
+                                      struct.pack('ii', 1, 1))
                 connection.handshakeServer(certChain=cert_chain,
                                               privateKey=privateKey,
                                               verifierDB=verifierDB,

tlslite/tlsconnection.py

@@ -2211,9 +2211,9 @@ def _serverTLS13Handshake(self, settings, clientHello, cipherSuite,
             ext = SupportedGroupsExtension()
             groups = [getattr(GroupName, i) for i in settings.keyShares]
             groups += [getattr(GroupName, i) for i in settings.eccCurves
-                       if i not in groups]
+                       if getattr(GroupName, i) not in groups]
             groups += [getattr(GroupName, i) for i in settings.dhGroups
-                       if i not in groups]
+                       if getattr(GroupName, i) not in groups]
             if groups:
                 ext.create(groups)
                 ee_extensions.append(ext)

tlslite/utils/cryptomath.py

@@ -253,8 +253,7 @@ def numBytes(n):
 # **************************************************************************
 
 def getRandomNumber(low, high):
-    if low >= high:
-        raise AssertionError()
+    assert low < high
     howManyBits = numBits(high)
     howManyBytes = numBytes(high)
     lastBits = howManyBits % 8
@@ -296,15 +295,8 @@ def powMod(base, power, modulus):
         modulus = gmpy.mpz(modulus)
         result = pow(base, power, modulus)
         return compatLong(result)
-
 else:
-    def powMod(base, power, modulus):
-        if power < 0:
-            result = pow(base, power*-1, modulus)
-            result = invMod(result, modulus)
-            return result
-        else:
-            return pow(base, power, modulus)
+    powMod = pow
 
 
 def divceil(divident, divisor):
@@ -353,9 +345,15 @@ def isPrime(n, iterations=5, display=False, sieve=makeSieve(1000)):
         a = getRandomNumber(2, n)
     return True
 
+
 def getRandomPrime(bits, display=False):
-    if bits < 10:
-        raise AssertionError()
+    """
+    Generate a random prime number of a given size.
+
+    the number will be 'bits' bits long (i.e. generated number will be
+    larger than `(2^(bits-1) * 3 ) / 2` but smaller than 2^bits.
+    """
+    assert bits >= 10
     #The 1.5 ensures the 2 MSBs are set
     #Thus, when used for p,q in RSA, n will have its MSB set
     #
@@ -374,10 +372,15 @@ def getRandomPrime(bits, display=False):
         if isPrime(p, display=display):
             return p
 
+
 #Unused at the moment...
 def getRandomSafePrime(bits, display=False):
-    if bits < 10:
-        raise AssertionError()
+    """Generate a random safe prime.
+
+    Will generate a prime `bits` bits long (see getRandomPrime) such that
+    the (p-1)/2 will also be prime.
+    """
+    assert bits >= 10
     #The 1.5 ensures the 2 MSBs are set
     #Thus, when used for p,q in RSA, n will have its MSB set
     #

unit_tests/test_tlslite_utils_cryptomath.py

@@ -16,7 +16,8 @@
 from tlslite.utils.cryptomath import isPrime, numBits, numBytes, \
         numberToByteArray, MD5, SHA1, secureHash, HMAC_MD5, HMAC_SHA1, \
         HMAC_SHA256, HMAC_SHA384, HKDF_expand, bytesToNumber, \
-        HKDF_expand_label, derive_secret, numberToMPI, mpiToNumber
+        HKDF_expand_label, derive_secret, numberToMPI, mpiToNumber, \
+        getRandomPrime, getRandomSafePrime, powMod
 from tlslite.handshakehashes import HandshakeHashes
 
 class TestIsPrime(unittest.TestCase):
@@ -193,6 +194,16 @@ def test_numBits(self, number):
     def test_numBytes(self, number):
         self.assertEqual(numBytes(number), self.num_bytes(number))
 
+
+class TestPowMod(unittest.TestCase):
+    def test_with_small_numbers(self):
+        self.assertEqual(2**10, powMod(2, 10, 10**6))
+
+    def test_with_mod(self):
+        self.assertEqual(4, powMod(3, 10, 5))
+        self.assertEqual(2, powMod(3, 11, 5))
+
+
 class TestHMACMethods(unittest.TestCase):
     def test_HMAC_MD5(self):
         self.assertEqual(HMAC_MD5(b'abc', b'def'),
@@ -518,3 +529,16 @@ def test_fromMPI(self):
     def test_fromMPI_with_negative_number(self):
         with self.assertRaises(ValueError):
             mpiToNumber(bytearray(b'\x00\x00\x00\x01\xc8'))
+
+
+class TestPrimeGeneration(unittest.TestCase):
+    def test_getRangomPrime(self):
+        r = getRandomPrime(20)
+        self.assertEqual(numBits(r), 20)
+        self.assertTrue(isPrime(r))
+
+    def test_getRandomSafePrime(self):
+        r = getRandomSafePrime(20)
+        self.assertEqual(numBits(r), 20)
+        self.assertTrue(isPrime(r))
+        self.assertTrue(isPrime((r-1)//2))