src/IPv4Address.hs

   1 module IPv4Address
   2 ( ipv4address_from_octets,
   3   ipv4address_tests,
   4   IPv4Address(None),
   5   max_address,
   6   min_address,
   7   most_sig_bit_different,
   8   octet1,
   9   octet2,
  10   octet3,
  11   octet4
  12 ) where
  13
  14 import Test.HUnit
  15 import Test.QuickCheck
  16
  17 import Maskable
  18 import Maskbits
  19 import Octet
  20
  21 data IPv4Address = None | IPv4Address { octet1 :: Octet,
  22                                         octet2 :: Octet,
  23                                         octet3 :: Octet,
  24                                         octet4 :: Octet }
  25                  deriving (Eq)
  26
  27
  28 instance Show IPv4Address where
  29     show IPv4Address.None = "None"
  30     show addr = concat [(show oct1) ++ ".",
  31                         (show oct2) ++ ".",
  32                         (show oct3) ++ ".",
  33                         (show oct4)]
  34         where
  35           oct1 = (octet1 addr)
  36           oct2 = (octet2 addr)
  37           oct3 = (octet3 addr)
  38           oct4 = (octet4 addr)
  39
  40
  41 instance Arbitrary IPv4Address where
  42     arbitrary = do
  43       oct1 <- arbitrary :: Gen Octet
  44       oct2 <- arbitrary :: Gen Octet
  45       oct3 <- arbitrary :: Gen Octet
  46       oct4 <- arbitrary :: Gen Octet
  47       return (IPv4Address oct1 oct2 oct3 oct4)
  48
  49     coarbitrary _ = variant 0
  50
  51
  52
  53 instance Maskable IPv4Address where
  54     apply_mask _ Maskbits.None _ = IPv4Address.None
  55     apply_mask addr mask bit
  56         | mask == ThirtyTwo = addr
  57         | mask == ThirtyOne = addr { octet4 = (apply_mask oct4 Seven bit) }
  58         | mask == Thirty = addr { octet4 = (apply_mask oct4 Six bit) }
  59         | mask == TwentyNine = addr { octet4 = (apply_mask oct4 Five bit) }
  60         | mask == TwentyEight = addr { octet4 = (apply_mask oct4 Four bit) }
  61         | mask == TwentySeven = addr { octet4 = (apply_mask oct4 Three bit) }
  62         | mask == TwentySix = addr { octet4 = (apply_mask oct4 Two bit) }
  63         | mask == TwentyFive = addr { octet4 = (apply_mask oct4 One bit) }
  64         | mask == TwentyFour = addr { octet4 = min_octet }
  65         | mask == TwentyThree = addr { octet3 = (apply_mask oct3 Seven bit),
  66                                        octet4 = min_octet }
  67         | mask == TwentyTwo = addr { octet3 = (apply_mask oct3 Six bit),
  68                                      octet4 = min_octet }
  69         | mask == TwentyOne = addr { octet3 = (apply_mask oct3 Five bit),
  70                                      octet4 = min_octet }
  71         | mask == Twenty = addr { octet3 = (apply_mask oct3 Four bit),
  72                                   octet4 = min_octet }
  73         | mask == Nineteen = addr { octet3 = (apply_mask oct3 Three bit),
  74                                     octet4 = min_octet }
  75         | mask == Eighteen = addr { octet3 = (apply_mask oct3 Two bit),
  76                                     octet4 = min_octet }
  77         | mask == Seventeen = addr { octet3 = (apply_mask oct3 One bit),
  78                                      octet4 = min_octet }
  79         | mask == Sixteen = addr { octet3 = min_octet,
  80                                    octet4 = min_octet }
  81         | mask == Fifteen = min_address { octet1 = oct1,
  82                                           octet2 = (apply_mask oct2 Seven bit) }
  83         | mask == Fourteen = min_address { octet1 = oct1,
  84                                            octet2 = (apply_mask oct2 Six bit) }
  85         | mask == Thirteen = min_address { octet1 = oct1,
  86                                            octet2 = (apply_mask oct2 Five bit) }
  87         | mask == Twelve = min_address { octet1 = oct1,
  88                                          octet2 = (apply_mask oct2 Four bit) }
  89         | mask == Eleven = min_address { octet1 = oct1,
  90                                          octet2 = (apply_mask oct2 Three bit) }
  91         | mask == Ten = min_address { octet1 = oct1,
  92                                       octet2 = (apply_mask oct2 Two bit) }
  93         | mask == Nine = min_address { octet1 = oct1,
  94                                        octet2 = (apply_mask oct2 One bit) }
  95         | mask == Eight = min_address { octet1 = oct1 }
  96         | mask == Seven = min_address { octet1 = (apply_mask oct1 Seven bit) }
  97         | mask == Six = min_address { octet1 = (apply_mask oct1 Six bit) }
  98         | mask == Five = min_address { octet1 = (apply_mask oct1 Five bit) }
  99         | mask == Four = min_address { octet1 = (apply_mask oct1 Four bit) }
 100         | mask == Three = min_address { octet1 = (apply_mask oct1 Three bit) }
 101         | mask == Two = min_address { octet1 = (apply_mask oct1 Two bit) }
 102         | mask == One = min_address { octet1 = (apply_mask oct1 One bit) }
 103         | mask == Zero = min_address
 104         | otherwise = IPv4Address.None
 105         where
 106           oct1 = (octet1 addr)
 107           oct2 = (octet2 addr)
 108           oct3 = (octet3 addr)
 109           oct4 = (octet4 addr)
 110
 111
 112 -- We don't export our constructor so this function is the only
 113 -- way to construct an address from octets. As a result, we can
 114 -- return IPv4Address.None in response to being passed one of more
 115 -- Octet.None octets.
 116 ipv4address_from_octets :: Octet -> Octet -> Octet -> Octet -> IPv4Address
 117 ipv4address_from_octets oct1 oct2 oct3 oct4
 118     | or [oct1 == Octet.None,
 119           oct2 == Octet.None,
 120           oct3 == Octet.None,
 121           oct4 == Octet.None] = IPv4Address.None
 122     | otherwise = IPv4Address oct1 oct2 oct3 oct4
 123
 124
 125 -- The minimum possible IPv4 address, 0.0.0.0.
 126 min_address :: IPv4Address
 127 min_address = IPv4Address min_octet min_octet min_octet min_octet
 128
 129
 130 -- The maximum possible IPv4 address, 255.255.255.255.
 131 max_address :: IPv4Address
 132 max_address = IPv4Address max_octet max_octet max_octet max_octet
 133
 134
 135 -- Given two addresses, find the number of the most significant bit
 136 -- where they differ. If the addresses are the same, return
 137 -- Maskbits.Zero.
 138 most_sig_bit_different :: IPv4Address -> IPv4Address -> Maskbits
 139 most_sig_bit_different addr1 addr2
 140   | addr1 == addr2 = Maskbits.Zero
 141   | m1  /= n1  = Maskbits.One
 142   | m2  /= n2  = Two
 143   | m3  /= n3  = Three
 144   | m4  /= n4  = Four
 145   | m5  /= n5  = Five
 146   | m6  /= n6  = Six
 147   | m7  /= n7  = Seven
 148   | m8  /= n8  = Eight
 149   | m9  /= n9  = Nine
 150   | m10 /= n10 = Ten
 151   | m11 /= n11 = Eleven
 152   | m12 /= n12 = Twelve
 153   | m13 /= n13 = Thirteen
 154   | m14 /= n14 = Fourteen
 155   | m15 /= n15 = Fifteen
 156   | m16 /= n16 = Sixteen
 157   | m17 /= n17 = Seventeen
 158   | m18 /= n18 = Eighteen
 159   | m19 /= n19 = Nineteen
 160   | m20 /= n20 = Twenty
 161   | m21 /= n21 = TwentyOne
 162   | m22 /= n22 = TwentyTwo
 163   | m23 /= n23 = TwentyThree
 164   | m24 /= n24 = TwentyFour
 165   | m25 /= n25 = TwentyFive
 166   | m26 /= n26 = TwentySix
 167   | m27 /= n27 = TwentySeven
 168   | m28 /= n28 = TwentyEight
 169   | m29 /= n29 = TwentyNine
 170   | m30 /= n30 = Thirty
 171   | m31 /= n31 = ThirtyOne
 172   | m32 /= n32 = ThirtyTwo
 173   | otherwise  = Maskbits.Zero
 174   where
 175     m1  = (b1 oct1a)
 176     m2  = (b2 oct1a)
 177     m3  = (b3 oct1a)
 178     m4  = (b4 oct1a)
 179     m5  = (b5 oct1a)
 180     m6  = (b6 oct1a)
 181     m7  = (b7 oct1a)
 182     m8  = (b8 oct1a)
 183     m9  = (b1 oct2a)
 184     m10 = (b2 oct2a)
 185     m11 = (b3 oct2a)
 186     m12 = (b4 oct2a)
 187     m13 = (b5 oct2a)
 188     m14 = (b6 oct2a)
 189     m15 = (b7 oct2a)
 190     m16 = (b8 oct2a)
 191     m17 = (b1 oct3a)
 192     m18 = (b2 oct3a)
 193     m19 = (b3 oct3a)
 194     m20 = (b4 oct3a)
 195     m21 = (b5 oct3a)
 196     m22 = (b6 oct3a)
 197     m23 = (b7 oct3a)
 198     m24 = (b8 oct3a)
 199     m25 = (b1 oct4a)
 200     m26 = (b2 oct4a)
 201     m27 = (b3 oct4a)
 202     m28 = (b4 oct4a)
 203     m29 = (b5 oct4a)
 204     m30 = (b6 oct4a)
 205     m31 = (b7 oct4a)
 206     m32 = (b8 oct4a)
 207     oct1a = (octet1 addr1)
 208     oct2a = (octet2 addr1)
 209     oct3a = (octet3 addr1)
 210     oct4a = (octet4 addr1)
 211     n1  = (b1 oct1b)
 212     n2  = (b2 oct1b)
 213     n3  = (b3 oct1b)
 214     n4  = (b4 oct1b)
 215     n5  = (b5 oct1b)
 216     n6  = (b6 oct1b)
 217     n7  = (b7 oct1b)
 218     n8  = (b8 oct1b)
 219     n9  = (b1 oct2b)
 220     n10 = (b2 oct2b)
 221     n11 = (b3 oct2b)
 222     n12 = (b4 oct2b)
 223     n13 = (b5 oct2b)
 224     n14 = (b6 oct2b)
 225     n15 = (b7 oct2b)
 226     n16 = (b8 oct2b)
 227     n17 = (b1 oct3b)
 228     n18 = (b2 oct3b)
 229     n19 = (b3 oct3b)
 230     n20 = (b4 oct3b)
 231     n21 = (b5 oct3b)
 232     n22 = (b6 oct3b)
 233     n23 = (b7 oct3b)
 234     n24 = (b8 oct3b)
 235     n25 = (b1 oct4b)
 236     n26 = (b2 oct4b)
 237     n27 = (b3 oct4b)
 238     n28 = (b4 oct4b)
 239     n29 = (b5 oct4b)
 240     n30 = (b6 oct4b)
 241     n31 = (b7 oct4b)
 242     n32 = (b8 oct4b)
 243     oct1b = (octet1 addr2)
 244     oct2b = (octet2 addr2)
 245     oct3b = (octet3 addr2)
 246     oct4b = (octet4 addr2)
 247
 248
 249
 250 -- HUnit Tests
 251 mk_testaddr :: Int -> Int -> Int -> Int -> IPv4Address
 252 mk_testaddr a b c d =
 253     IPv4Address oct1 oct2 oct3 oct4
 254     where
 255       oct1 = octet_from_int a
 256       oct2 = octet_from_int b
 257       oct3 = octet_from_int c
 258       oct4 = octet_from_int d
 259
 260
 261 test_most_sig_bit_different1 :: Test
 262 test_most_sig_bit_different1 =
 263     TestCase $ assertEqual "10.1.1.0 and 10.1.0.0 differ in bit 24" TwentyFour (most_sig_bit_different (mk_testaddr 10 1 1 0) (mk_testaddr 10 1 0 0))
 264
 265
 266 test_most_sig_bit_different2 :: Test
 267 test_most_sig_bit_different2 =
 268     TestCase $ assertEqual "10.1.2.0 and 10.1.1.0 differ in bit 23" TwentyThree (most_sig_bit_different (mk_testaddr 10 1 2 0) (mk_testaddr 10 1 1 0))
 269
 270
 271 ipv4address_tests :: [Test]
 272 ipv4address_tests = [ test_most_sig_bit_different1,
 273                       test_most_sig_bit_different2 ]