-module IPv4Address
-( ipv4address_tests,
+module IPv4Address(
+ ipv4address_properties,
+ ipv4address_tests,
IPv4Address(..),
- max_address,
- min_address,
most_sig_bit_different,
) where
import Data.Maybe (fromJust)
-import Test.HUnit
-import Test.QuickCheck
+import Test.HUnit (assertEqual)
+import Test.Framework (Test, testGroup)
+import Test.Framework.Providers.HUnit (testCase)
+import Test.Framework.Providers.QuickCheck2 (testProperty)
+import Test.QuickCheck (Arbitrary(..), Gen, Property, (==>))
import Maskable
import Maskbits
instance Maskable IPv4Address where
- apply_mask addr mask bit
- | mask == ThirtyTwo = addr
- | mask == ThirtyOne = addr { octet4 = (apply_mask oct4 Seven bit) }
- | mask == Thirty = addr { octet4 = (apply_mask oct4 Six bit) }
- | mask == TwentyNine = addr { octet4 = (apply_mask oct4 Five bit) }
- | mask == TwentyEight = addr { octet4 = (apply_mask oct4 Four bit) }
- | mask == TwentySeven = addr { octet4 = (apply_mask oct4 Three bit) }
- | mask == TwentySix = addr { octet4 = (apply_mask oct4 Two bit) }
- | mask == TwentyFive = addr { octet4 = (apply_mask oct4 One bit) }
- | mask == TwentyFour = addr { octet4 = (apply_mask oct4 Zero bit) }
- | mask == TwentyThree = addr { octet3 = (apply_mask oct3 Seven bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == TwentyTwo = addr { octet3 = (apply_mask oct3 Six bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == TwentyOne = addr { octet3 = (apply_mask oct3 Five bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == Twenty = addr { octet3 = (apply_mask oct3 Four bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == Nineteen = addr { octet3 = (apply_mask oct3 Three bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == Eighteen = addr { octet3 = (apply_mask oct3 Two bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == Seventeen = addr { octet3 = (apply_mask oct3 One bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == Sixteen = addr { octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == Fifteen = addr { octet2 = (apply_mask oct2 Seven bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit) }
- | mask == Fourteen = addr { octet2 = (apply_mask oct2 Six bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Thirteen = addr { octet2 = (apply_mask oct2 Five bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Twelve = addr { octet2 = (apply_mask oct2 Four bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Eleven = addr { octet2 = (apply_mask oct2 Three bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Ten = addr { octet2 = (apply_mask oct2 Two bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Nine = addr { octet2 = (apply_mask oct2 One bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Eight = addr { octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Seven = addr { octet1 = (apply_mask oct1 Seven bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Six = addr { octet1 = (apply_mask oct1 Six bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Five = addr { octet1 = (apply_mask oct1 Five bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Four = addr { octet1 = (apply_mask oct1 Four bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Three = addr { octet1 = (apply_mask oct1 Three bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Two = addr { octet1 = (apply_mask oct1 Two bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == One = addr { octet1 = (apply_mask oct1 One bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- | mask == Zero = addr { octet1 = (apply_mask oct1 Zero bit),
- octet2 = (apply_mask oct2 Zero bit),
- octet3 = (apply_mask oct3 Zero bit),
- octet4 = (apply_mask oct4 Zero bit)}
- where
- oct1 = (octet1 addr)
- oct2 = (octet2 addr)
- oct3 = (octet3 addr)
- oct4 = (octet4 addr)
+ apply_mask addr mask bit =
+ apply_mask' mask
+ where
+ oct1 = octet1 addr
+ oct2 = octet2 addr
+ oct3 = octet3 addr
+ oct4 = octet4 addr
+
+ -- A copy of 'addr' with the fourth octet zeroed (or oned).
+ new_addr1 = addr { octet4 = (apply_mask oct4 Zero bit) }
+
+ -- Likewise for new_addr1's third octet.
+ new_addr2 = new_addr1 { octet3 = (apply_mask oct3 Zero bit) }
+
+ -- And new_addr2's second octet.
+ new_addr3 = new_addr2 { octet2 = (apply_mask oct2 Zero bit) }
+
+ -- This helper function allows us to pattern-match cleanly.
+ apply_mask' :: Maskbits -> IPv4Address
+
+ apply_mask' ThirtyTwo = addr
+
+ apply_mask' ThirtyOne = addr { octet4 = (apply_mask oct4 Seven bit) }
+
+ apply_mask' Thirty =
+ addr { octet4 = (apply_mask oct4 Six bit) }
+
+ apply_mask' TwentyNine =
+ addr { octet4 = (apply_mask oct4 Five bit) }
+
+ apply_mask' TwentyEight =
+ addr { octet4 = (apply_mask oct4 Four bit) }
+
+ apply_mask' TwentySeven =
+ addr { octet4 = (apply_mask oct4 Three bit) }
+
+ apply_mask' TwentySix =
+ addr { octet4 = (apply_mask oct4 Two bit) }
+
+ apply_mask' TwentyFive =
+ addr { octet4 = (apply_mask oct4 One bit) }
+
+ apply_mask' TwentyFour = new_addr1
+
+ apply_mask' TwentyThree =
+ new_addr1 { octet3 = (apply_mask oct3 Seven bit) }
+
+ apply_mask' TwentyTwo =
+ new_addr1 { octet3 = (apply_mask oct3 Six bit) }
+
+ apply_mask' TwentyOne =
+ new_addr1 { octet3 = (apply_mask oct3 Five bit) }
+
+ apply_mask' Twenty =
+ new_addr1 { octet3 = (apply_mask oct3 Four bit) }
+
+ apply_mask' Nineteen =
+ new_addr1 { octet3 = (apply_mask oct3 Three bit) }
+
+ apply_mask' Eighteen =
+ new_addr1 { octet3 = (apply_mask oct3 Two bit) }
+
+ apply_mask' Seventeen =
+ new_addr1 { octet3 = (apply_mask oct3 One bit) }
+
+ apply_mask' Sixteen =
+ new_addr2
+
+ apply_mask' Fifteen =
+ new_addr2 { octet2 = (apply_mask oct2 Seven bit) }
+
+ apply_mask' Fourteen =
+ new_addr2 { octet2 = (apply_mask oct2 Six bit) }
+
+ apply_mask' Thirteen =
+ new_addr2 { octet2 = (apply_mask oct2 Five bit) }
+
+ apply_mask' Twelve =
+ new_addr2 { octet2 = (apply_mask oct2 Four bit) }
+
+ apply_mask' Eleven =
+ new_addr2 { octet2 = (apply_mask oct2 Three bit) }
+ apply_mask' Ten =
+ new_addr2 { octet2 = (apply_mask oct2 Two bit) }
--- | The minimum possible IPv4 address, 0.0.0.0.
-min_address :: IPv4Address
-min_address =
- IPv4Address min_octet min_octet min_octet min_octet
+ apply_mask' Nine =
+ new_addr2 { octet2 = (apply_mask oct2 One bit) }
+ apply_mask' Eight =
+ new_addr3 { octet2 = (apply_mask oct2 Zero bit) }
--- | The maximum possible IPv4 address, 255.255.255.255.
-max_address :: IPv4Address
-max_address =
- IPv4Address max_octet max_octet max_octet max_octet
+ apply_mask' Seven =
+ new_addr3 { octet1 = (apply_mask oct1 Seven bit) }
+ apply_mask' Six =
+ new_addr3 { octet1 = (apply_mask oct1 Six bit) }
+
+ apply_mask' Five =
+ new_addr3 { octet1 = (apply_mask oct1 Five bit) }
+
+ apply_mask' Four =
+ new_addr3 { octet1 = (apply_mask oct1 Four bit) }
+
+ apply_mask' Three =
+ new_addr3 { octet1 = (apply_mask oct1 Three bit) }
+
+ apply_mask' Two =
+ new_addr3 { octet1 = (apply_mask oct1 Two bit) }
+
+ apply_mask' One =
+ new_addr3 { octet1 = (apply_mask oct1 One bit) }
+
+ apply_mask' Zero =
+ new_addr3 { octet1 = (apply_mask oct1 Zero bit) }
+
+
+instance Bounded IPv4Address where
+ -- | The minimum possible IPv4 address, 0.0.0.0.
+ minBound = IPv4Address minBound minBound minBound minBound
+
+ -- | The maximum possible IPv4 address, 255.255.255.255.
+ maxBound = IPv4Address maxBound maxBound maxBound maxBound
+
+
+
+-- | Convert @addr@ to an 'Int' by converting each octet to an 'Int'
+-- and shifting the result to the left by 0,8.16, or 24 bits.
+ipv4address_to_int :: IPv4Address -> Int
+ipv4address_to_int addr =
+ (shifted_oct1) + (shifted_oct2) + (shifted_oct3) + oct4
+ where
+ oct1 = octet_to_int (octet1 addr)
+ oct2 = octet_to_int (octet2 addr)
+ oct3 = octet_to_int (octet3 addr)
+ oct4 = octet_to_int (octet4 addr)
+
+ shifted_oct1 = oct1 * 2^(24 :: Integer)
+ shifted_oct2 = oct2 * 2^(16 :: Integer)
+ shifted_oct3 = oct3 * 2^(8 :: Integer)
+
+
+
+-- | Convert an 'Int' @x@ to an 'IPv4Address'. Each octet of @x@ is
+-- right-shifted by the appropriate number of bits, and the fractional
+-- part is dropped.
+ipv4address_from_int :: Int -> Maybe IPv4Address
+ipv4address_from_int x
+ | (x < 0) || (x > 2^(32 :: Integer) - 1) = Nothing
+ | otherwise = do
+ -- If the algebra is right, none of these octet_from_int calls
+ -- below can fail since 0 <= x <= 2^32 - 1.
+ oct1 <- octet_from_int shifted_x1
+ oct2 <- octet_from_int shifted_x2
+ oct3 <- octet_from_int shifted_x3
+ oct4 <- octet_from_int x4
+ return $ IPv4Address oct1 oct2 oct3 oct4
+ where
+ -- Chop off the higher octets. x1 = x `mod` 2^32, would be
+ -- redundant.
+ x2 = x `mod` 2^(24 :: Integer)
+ x3 = x `mod` 2^(16 :: Integer)
+ x4 = x `mod` 2^(8 :: Integer)
+ -- Perform right-shifts. x4 doesn't need a shift.
+ shifted_x1 = x `quot` 2^(24 :: Integer)
+ shifted_x2 = x2 `quot` 2^(16 :: Integer)
+ shifted_x3 = x3 `quot` 2^(8 :: Integer)
+
+
+instance Enum IPv4Address where
+ -- We're supposed to throw a runtime error if you call (succ
+ -- maxBound), so the fromJust here doesn't introduce any additional
+ -- badness.
+ toEnum = fromJust . ipv4address_from_int
+ fromEnum = ipv4address_to_int
-- | Given two addresses, find the number of the most significant bit
-- where they differ. If the addresses are the same, return
oct4b = (octet4 addr2)
+-- Test lists.
+ipv4address_tests :: Test
+ipv4address_tests =
+ testGroup "IPv4 Address Tests" [
+ test_enum,
+ test_maxBound,
+ test_minBound,
+ test_most_sig_bit_different1,
+ test_most_sig_bit_different2 ]
+
+ipv4address_properties :: Test
+ipv4address_properties =
+ testGroup
+ "IPv4 Address Properties "
+ [ testProperty
+ "fromEnum/toEnum are inverses"
+ prop_from_enum_to_enum_inverses ]
+
+-- QuickCheck properties
+prop_from_enum_to_enum_inverses :: Int -> Property
+prop_from_enum_to_enum_inverses x =
+ (0 <= x) && (x <= 2^(32 :: Integer) - 1) ==>
+ fromEnum (toEnum x :: IPv4Address) == x
-- HUnit Tests
mk_testaddr :: Int -> Int -> Int -> Int -> IPv4Address
oct3 = fromJust $ octet_from_int c
oct4 = fromJust $ octet_from_int d
+test_minBound :: Test
+test_minBound =
+ testCase desc $ assertEqual desc expected actual
+ where
+ desc = "minBound should be 0.0.0.0"
+ expected = mk_testaddr 0 0 0 0
+ actual = minBound :: IPv4Address
+
+test_maxBound :: Test
+test_maxBound =
+ testCase desc $ assertEqual desc expected actual
+ where
+ desc = "maxBound should be 255.255.255.255"
+ expected = mk_testaddr 255 255 255 255
+ actual = maxBound :: IPv4Address
+
+test_enum :: Test
+test_enum =
+ testCase desc $ assertEqual desc expected actual
+ where
+ desc = "enumerating a /24 gives the correct addresses"
+ expected = ["192.168.0." ++ (show x) | x <- [0..255::Int] ]
+ lb = mk_testaddr 192 168 0 0
+ ub = mk_testaddr 192 168 0 255
+ actual = map show [lb..ub]
test_most_sig_bit_different1 :: Test
test_most_sig_bit_different1 =
- TestCase $ assertEqual "10.1.1.0 and 10.1.0.0 differ in bit 24"
+ testCase desc $ assertEqual desc
TwentyFour
bit
where
+ desc = "10.1.1.0 and 10.1.0.0 differ in bit 24"
addr1 = mk_testaddr 10 1 1 0
addr2 = (mk_testaddr 10 1 0 0)
bit = most_sig_bit_different addr1 addr2
test_most_sig_bit_different2 :: Test
test_most_sig_bit_different2 =
- TestCase $ assertEqual "10.1.2.0 and 10.1.1.0 differ in bit 23"
+ testCase desc $ assertEqual desc
TwentyThree
bit
where
+ desc = "10.1.2.0 and 10.1.1.0 differ in bit 23"
addr1 = mk_testaddr 10 1 2 0
addr2 = mk_testaddr 10 1 1 0
bit = most_sig_bit_different addr1 addr2
-ipv4address_tests :: [Test]
-ipv4address_tests =
- [ test_most_sig_bit_different1,
- test_most_sig_bit_different2 ]