src/Cidr.hs

   1 module Cidr
   2 ( Cidr(..),
   3   cidr_from_string,
   4   cidr_tests,
   5   combine_all,
   6   contains,
   7   contains_proper,
   8   max_octet1,
   9   max_octet2,
  10   max_octet3,
  11   max_octet4,
  12   min_octet1,
  13   min_octet2,
  14   min_octet3,
  15   min_octet4,
  16   prop_all_cidrs_contain_themselves,
  17   prop_contains_proper_intransitive
  18 ) where
  19
  20 import Data.List (nubBy)
  21 import Test.HUnit
  22 import Test.QuickCheck
  23
  24 import qualified Bit as B
  25 import IPv4Address
  26 import ListUtils
  27 import Maskable
  28 import Maskbits
  29 import Octet
  30
  31
  32 data Cidr = None | Cidr { ipv4address :: IPv4Address,
  33                           maskbits :: Maskbits }
  34             deriving (Eq)
  35
  36
  37 instance Show Cidr where
  38     show Cidr.None = "None"
  39     show cidr = (show (ipv4address cidr)) ++ "/" ++ (show (maskbits cidr))
  40
  41
  42 instance Arbitrary Cidr where
  43     arbitrary = do
  44       ipv4 <- arbitrary :: Gen IPv4Address
  45       mask <- arbitrary :: Gen Maskbits
  46       return (Cidr ipv4 mask)
  47
  48     coarbitrary _ = variant 0
  49
  50
  51 -- Two CIDR ranges are equivalent if they have the same network bits
  52 -- and the masks are the same.
  53 equivalent :: Cidr -> Cidr -> Bool
  54 equivalent Cidr.None Cidr.None = True
  55 equivalent Cidr.None _ = False
  56 equivalent _ Cidr.None = False
  57 equivalent (Cidr addr1 mbits1) (Cidr addr2 mbits2) =
  58     (mbits1 == mbits2) && ((apply_mask addr1 mbits1) == (apply_mask addr2 mbits2))
  59
  60 -- Returns the mask portion of a CIDR address. That is, everything
  61 -- after the trailing slash.
  62 maskbits_from_cidr_string :: String -> Maskbits
  63 maskbits_from_cidr_string s =
  64     maskbits_from_string ((splitWith (`elem` "/") s) !! 1)
  65
  66
  67 -- Takes an IP address String in CIDR notation, and returns a list of
  68 -- its octets (as Ints).
  69 octets_from_cidr_string :: String -> [Octet]
  70 octets_from_cidr_string s =
  71     map octet_from_string (take 4 (splitWith (`elem` "./") s))
  72
  73
  74 cidr_from_string :: String -> Cidr
  75 cidr_from_string s
  76     | addr  == IPv4Address.None = Cidr.None
  77     | mbits == Maskbits.None    = Cidr.None
  78     | otherwise = Cidr addr mbits
  79                where
  80                  addr = ipv4address_from_octets (oct1) (oct2) (oct3) (oct4)
  81                  oct1 = (octs !! 0)
  82                  oct2 = (octs !! 1)
  83                  oct3 = (octs !! 2)
  84                  oct4 = (octs !! 3)
  85                  octs  = octets_from_cidr_string s
  86                  mbits = maskbits_from_cidr_string s
  87
  88
  89
  90 min_host :: Cidr -> IPv4Address
  91 min_host Cidr.None                 = IPv4Address.None
  92 min_host (Cidr IPv4Address.None _) = IPv4Address.None
  93 min_host (Cidr _ Maskbits.None)    = IPv4Address.None
  94 min_host (Cidr addr mask)
  95     | mask == ThirtyTwo = addr
  96     | mask == ThirtyOne = addr { octet4 = apply_mask oct4 Seven }
  97     | mask == Thirty = addr { octet4 = apply_mask oct4 Six }
  98     | mask == TwentyNine = addr { octet4 = apply_mask oct4 Five }
  99     | mask == TwentyEight = addr { octet4 = apply_mask oct4 Four }
 100     | mask == TwentySeven = addr { octet4 = apply_mask oct4 Three }
 101     | mask == TwentySix = addr { octet4 = apply_mask oct4 Two }
 102     | mask == TwentyFive = addr { octet4 = apply_mask oct4 One }
 103     | mask == TwentyFour = addr { octet4 = min_octet }
 104     | mask == TwentyThree = addr { octet3 = apply_mask oct3 Seven,
 105                                    octet4 = min_octet }
 106     | mask == TwentyTwo = addr { octet3 = apply_mask oct3 Six,
 107                                  octet4 = min_octet }
 108     | mask == TwentyOne = addr { octet3 = apply_mask oct3 Five,
 109                                  octet4 = min_octet }
 110     | mask == Twenty = addr { octet3 = apply_mask oct3 Four,
 111                               octet4 = min_octet }
 112     | mask == Nineteen = addr { octet3 = apply_mask oct3 Three,
 113                                 octet4 = min_octet }
 114     | mask == Eighteen = addr { octet3 = apply_mask oct3 Two,
 115                                 octet4 = min_octet }
 116     | mask == Seventeen = addr { octet3 = apply_mask oct3 One,
 117                                  octet4 = min_octet }
 118     | mask == Sixteen = addr { octet3 = min_octet,
 119                                octet4 = min_octet }
 120     | mask == Fifteen = addr { octet2 = apply_mask oct2 Seven,
 121                                octet3 = min_octet,
 122                                octet4 = min_octet }
 123     | mask == Fourteen = addr { octet2 = apply_mask oct2 Six,
 124                                 octet3 = min_octet,
 125                                 octet4 = min_octet }
 126     | mask == Thirteen = addr { octet2 = apply_mask oct2 Five,
 127                                 octet3 = min_octet,
 128                                 octet4 = min_octet }
 129     | mask == Twelve = addr { octet2 = apply_mask oct2 Four,
 130                               octet3 = min_octet,
 131                               octet4 = min_octet }
 132     | mask == Eleven = addr { octet2 = apply_mask oct2 Three,
 133                               octet3 = min_octet,
 134                               octet4 = min_octet }
 135     | mask == Ten = addr { octet2 = apply_mask oct2 Two,
 136                            octet3 = min_octet,
 137                            octet4 = min_octet }
 138     | mask == Nine = addr { octet2 = apply_mask oct2 One,
 139                             octet3 = min_octet,
 140                             octet4 = min_octet }
 141     | mask == Eight = addr { octet2 = min_octet,
 142                              octet3 = min_octet,
 143                              octet4 = min_octet }
 144     | mask == Seven = addr { octet1 = apply_mask oct1 Seven,
 145                              octet2 = min_octet,
 146                              octet3 = min_octet,
 147                              octet4 = min_octet }
 148     | mask == Six = addr { octet1 = apply_mask oct1 Six,
 149                            octet2 = min_octet,
 150                            octet3 = min_octet,
 151                            octet4 = min_octet }
 152     | mask == Five = addr { octet1 = apply_mask oct1 Five,
 153                             octet2 = min_octet,
 154                             octet3 = min_octet,
 155                             octet4 = min_octet }
 156     | mask == Four = addr { octet1 = apply_mask oct1 Four,
 157                             octet2 = min_octet,
 158                             octet3 = min_octet,
 159                             octet4 = min_octet }
 160     | mask == Three = addr { octet1 = apply_mask oct1 Three,
 161                              octet2 = min_octet,
 162                              octet3 = min_octet,
 163                              octet4 = min_octet }
 164     | mask == Two = addr { octet1 = apply_mask oct1 Two,
 165                            octet2 = min_octet,
 166                            octet3 = min_octet,
 167                            octet4 = min_octet }
 168     | mask == One = addr { octet1 = apply_mask oct1 One,
 169                            octet2 = min_octet,
 170                            octet3 = min_octet,
 171                            octet4 = min_octet }
 172     | mask == Zero = addr { octet1 = min_octet,
 173                             octet2 = min_octet,
 174                             octet3 = min_octet,
 175                             octet4 = min_octet }
 176     | otherwise = addr
 177     where
 178       oct1 = (octet1 addr)
 179       oct2 = (octet2 addr)
 180       oct3 = (octet3 addr)
 181       oct4 = (octet4 addr)
 182
 183
 184
 185 max_host :: Cidr -> IPv4Address
 186 max_host Cidr.None                 = IPv4Address.None
 187 max_host (Cidr IPv4Address.None _) = IPv4Address.None
 188 max_host (Cidr _ Maskbits.None)    = IPv4Address.None
 189 max_host (Cidr addr mask)
 190     | mask == ThirtyTwo = addr
 191     | mask == ThirtyOne = addr { octet4 = oct4 { b8 = B.One } }
 192     | mask == Thirty = addr { octet4 = oct4 { b7 = B.One, b8 = B.One } }
 193     | mask == TwentyNine = addr { octet4 = oct4 { b6 = B.One,
 194                                                   b7 = B.One,
 195                                                   b8 = B.One } }
 196     | mask == TwentyEight = addr { octet4 = oct4 { b5 = B.One,
 197                                                    b6 = B.One,
 198                                                    b7 = B.One,
 199                                                    b8 = B.One } }
 200     | mask == TwentySeven = addr { octet4 = oct4 { b4 = B.One,
 201                                                    b5 = B.One,
 202                                                    b6 = B.One,
 203                                                    b7 = B.One,
 204                                                    b8 = B.One } }
 205     | mask == TwentySix = addr { octet4 = oct4 { b3 = B.One,
 206                                                  b4 = B.One,
 207                                                  b5 = B.One,
 208                                                  b6 = B.One,
 209                                                  b7 = B.One,
 210                                                  b8 = B.One } }
 211     | mask == TwentyFive = addr { octet4 = oct4 { b2 = B.One,
 212                                                   b3 = B.One,
 213                                                   b4 = B.One,
 214                                                   b5 = B.One,
 215                                                   b6 = B.One,
 216                                                   b7 = B.One,
 217                                                   b8 = B.One } }
 218     | mask == TwentyFour = addr { octet4 = max_octet }
 219     | mask == TwentyThree = ipv4address_from_octets oct1 oct2 (Octet a17 a18 a19 a20 a21 a22 a23 B.One) (max_octet)
 220     | mask == TwentyTwo = ipv4address_from_octets oct1 oct2 (Octet a17 a18 a19 a20 a21 a22 B.One B.One) (max_octet)
 221     | mask == TwentyOne = ipv4address_from_octets oct1 oct2 (Octet a17 a18 a19 a20 a21 B.One B.One B.One) (max_octet)
 222     | mask == Twenty = ipv4address_from_octets oct1 oct2 (Octet a17 a18 a19 a20 B.One B.One B.One B.One) (max_octet)
 223     | mask == Nineteen = ipv4address_from_octets oct1 oct2 (Octet a17 a18 a19 B.One B.One B.One B.One B.One) (max_octet)
 224     | mask == Eighteen = ipv4address_from_octets oct1 oct2 (Octet a17 a18 B.One B.One B.One B.One B.One B.One) (max_octet)
 225     | mask == Seventeen = ipv4address_from_octets oct1 oct2 (Octet a17 B.One B.One B.One B.One B.One B.One B.One) (max_octet)
 226     | mask == Sixteen = ipv4address_from_octets oct1 oct2 (max_octet) (max_octet)
 227     | mask == Fifteen = ipv4address_from_octets oct1 (Octet a9 a10 a11 a12 a13 a14 a15 B.One) (max_octet) (max_octet)
 228     | mask == Fourteen = ipv4address_from_octets oct1 (Octet a9 a10 a11 a12 a13 a14 B.One B.One) (max_octet) (max_octet)
 229     | mask == Thirteen = ipv4address_from_octets oct1 (Octet a9 a10 a11 a12 a13 B.One B.One B.One) (max_octet) (max_octet)
 230     | mask == Twelve = ipv4address_from_octets oct1 (Octet a9 a10 a11 a12 B.One B.One B.One B.One) (max_octet) (max_octet)
 231     | mask == Eleven = ipv4address_from_octets oct1 (Octet a9 a10 a11 B.One B.One B.One B.One B.One) (max_octet) (max_octet)
 232     | mask == Ten = ipv4address_from_octets oct1 (Octet a9 a10 B.One B.One B.One B.One B.One B.One) (max_octet) (max_octet)
 233     | mask == Nine = ipv4address_from_octets oct1 (Octet a9 B.One B.One B.One B.One B.One B.One B.One) (max_octet) (max_octet)
 234     | mask == Eight = ipv4address_from_octets oct1 (max_octet) (max_octet) (max_octet)
 235     | mask == Seven = ipv4address_from_octets (Octet a1 a2 a3 a4 a5 a6 a7 B.One) (max_octet) (max_octet) (max_octet)
 236     | mask == Six = ipv4address_from_octets (Octet a1 a2 a3 a4 a5 a6 B.One B.One) (max_octet) (max_octet) (max_octet)
 237     | mask == Five = ipv4address_from_octets (Octet a1 a2 a3 a4 a5 B.One B.One B.One) (max_octet) (max_octet) (max_octet)
 238     | mask == Four = ipv4address_from_octets (Octet a1 a2 a3 a4 B.One B.One B.One B.One) (max_octet) (max_octet) (max_octet)
 239     | mask == Three = ipv4address_from_octets (Octet a1 a2 a3 B.One B.One B.One B.One B.One) (max_octet) (max_octet) (max_octet)
 240     | mask == Two = ipv4address_from_octets (Octet a1 a2 B.One B.One B.One B.One B.One B.One) (max_octet) (max_octet) (max_octet)
 241     | mask == One = ipv4address_from_octets (Octet a1 B.One B.One B.One B.One B.One B.One B.One) (max_octet) (max_octet) (max_octet)
 242     | mask == Zero = ipv4address_from_octets (max_octet) (max_octet) (max_octet) (max_octet)
 243     | otherwise = addr
 244     where
 245       a1  = (b1 oct1)
 246       a2  = (b2 oct1)
 247       a3  = (b3 oct1)
 248       a4  = (b4 oct1)
 249       a5  = (b5 oct1)
 250       a6  = (b6 oct1)
 251       a7  = (b7 oct1)
 252       a9  = (b1 oct2)
 253       a10 = (b2 oct2)
 254       a11 = (b3 oct2)
 255       a12 = (b4 oct2)
 256       a13 = (b5 oct2)
 257       a14 = (b6 oct2)
 258       a15 = (b7 oct2)
 259       a17 = (b1 oct3)
 260       a18 = (b2 oct3)
 261       a19 = (b3 oct3)
 262       a20 = (b4 oct3)
 263       a21 = (b5 oct3)
 264       a22 = (b6 oct3)
 265       a23 = (b7 oct3)
 266       oct1 = (octet1 addr)
 267       oct2 = (octet2 addr)
 268       oct3 = (octet3 addr)
 269       oct4 = (octet4 addr)
 270
 271
 272
 273 min_octet1 :: Cidr -> Octet
 274 min_octet1 cidr = octet1 (min_host cidr)
 275
 276 min_octet2 :: Cidr -> Octet
 277 min_octet2 cidr = octet2 (min_host cidr)
 278
 279 min_octet3 :: Cidr -> Octet
 280 min_octet3 cidr = octet3 (min_host cidr)
 281
 282 min_octet4 :: Cidr -> Octet
 283 min_octet4 cidr = octet4 (min_host cidr)
 284
 285 max_octet1 :: Cidr -> Octet
 286 max_octet1 cidr = octet1 (max_host cidr)
 287
 288 max_octet2 :: Cidr -> Octet
 289 max_octet2 cidr = octet2 (max_host cidr)
 290
 291 max_octet3 :: Cidr -> Octet
 292 max_octet3 cidr = octet3 (max_host cidr)
 293
 294 max_octet4 :: Cidr -> Octet
 295 max_octet4 cidr = octet4 (max_host cidr)
 296
 297
 298
 299 -- Return true if the first argument (a CIDR range) contains the
 300 -- second (another CIDR range). There are a lot of ways we can be fed
 301 -- junk here. For lack of a better alternative, just return False when
 302 -- we are given nonsense.
 303 contains :: Cidr -> Cidr -> Bool
 304 contains Cidr.None _ = False
 305 contains _ Cidr.None = False
 306 contains (Cidr _ Maskbits.None) _    = False
 307 contains (Cidr IPv4Address.None _) _ = False
 308 contains _ (Cidr _ Maskbits.None)    = False
 309 contains _ (Cidr IPv4Address.None _) = False
 310
 311 -- If the number of bits in the network part of the first address is
 312 -- larger than the number of bits in the second, there is no way that
 313 -- the first range can contain the second. For, if the number of
 314 -- network bits is larger, then the number of host bits must be
 315 -- smaller, and if cidr1 has fewer hosts than cidr2, cidr1 most
 316 -- certainly does not contain cidr2.
 317 --
 318 -- On the other hand, if the first argument (cidr1) has fewer (or the
 319 -- same number of) network bits as the second, it can contain the
 320 -- second. In this case, we need to check that every host in cidr2 is
 321 -- contained in cidr1. If a host in cidr2 is contained in cidr1, then
 322 -- at least mbits1 of an address in cidr2 will match cidr1. For
 323 -- example,
 324 --
 325 -- cidr1 = 192.168.1.0/23, cidr2 = 192.168.1.100/24
 326 --
 327 -- Here, cidr2 contains all of 192.168.1.0 through
 328 -- 192.168.1.255. However, cidr1 contains BOTH 192.168.0.0 through
 329 -- 192.168.0.255 and 192.168.1.0 through 192.168.1.255. In essence,
 330 -- what we want to check is that cidr2 "begins with" something that
 331 -- cidr1 CAN begin with. Since cidr1 can begin with 192.168.1, and
 332 -- cidr2 DOES, cidr1 contains cidr2..
 333 --
 334 -- The way that we check this is to apply cidr1's mask to cidr2's
 335 -- address and see if the result is the same as cidr1's mask applied
 336 -- to cidr1's address.
 337 --
 338 contains (Cidr addr1 mbits1) (Cidr addr2 mbits2)
 339     | mbits1 > mbits2 = False
 340     | otherwise = addr1masked == addr2masked
 341     where
 342       addr1masked = apply_mask addr1 mbits1
 343       addr2masked = apply_mask addr2 mbits1
 344
 345
 346 contains_proper :: Cidr -> Cidr -> Bool
 347 contains_proper cidr1 cidr2 =
 348     (cidr1 `contains` cidr2) && (not (cidr2 `contains` cidr1))
 349
 350
 351 -- A CIDR range is redundant (with respect to the given list) if
 352 -- another CIDR range in that list properly contains it.
 353 redundant :: [Cidr] -> Cidr -> Bool
 354 redundant cidrlist cidr = any ((flip contains_proper) cidr) cidrlist
 355
 356
 357 -- First, we look at all possible pairs of cidrs, and combine the
 358 -- adjacent ones in to a new list. Then, we concatenate that list with
 359 -- the original one, and filter out all of the redundancies. If two
 360 -- adjacent Cidrs are combined into a larger one, they will be removed
 361 -- in the second step since the larger Cidr must contain the smaller
 362 -- two.
 363 combine_all :: [Cidr] -> [Cidr]
 364 combine_all cidrs =
 365     combine_contained unique_cidrs
 366     where
 367       unique_cidrs = nubBy equivalent valid_cidr_combinations
 368       valid_cidr_combinations = filter (/= Cidr.None) cidr_combinations
 369       cidr_combinations =
 370           cidrs ++ [ (combine_adjacent x y) | x <- cidrs, y <- cidrs ]
 371
 372
 373 -- Take a list of CIDR ranges and filter out all of the ones that are
 374 -- contained entirelt within some other range in the list.
 375 combine_contained :: [Cidr] -> [Cidr]
 376 combine_contained cidrs =
 377     filter (not . (redundant cidrs)) cidrs
 378
 379
 380 -- If the two Cidrs are not adjacent, return Cidr.None. Otherwise,
 381 -- decrement the maskbits of cidr1 and return that; it will contain
 382 -- both cidr1 and cidr2.
 383 combine_adjacent :: Cidr -> Cidr -> Cidr
 384 combine_adjacent cidr1 cidr2
 385   | not (adjacent cidr1 cidr2) = Cidr.None
 386   | (maskbits cidr1 == Zero) = Cidr.None
 387   | otherwise = cidr1 { maskbits = decrement (maskbits cidr1) }
 388
 389
 390
 391 -- Determine whether or not two CIDR ranges are adjacent. If two
 392 -- ranges lie consecutively within the IP space, they can be
 393 -- combined. For example, 10.1.0.0/24 and 10.0.1.0/24 are adjacent,
 394 -- and can be combined in to 10.1.0.0/23.
 395 adjacent :: Cidr -> Cidr -> Bool
 396 adjacent Cidr.None _ = False
 397 adjacent _ Cidr.None = False
 398 adjacent cidr1 cidr2
 399   | mbits1 /= mbits2 = False
 400   | mbits1 == Maskbits.Zero = False -- They're equal.
 401   | otherwise = (mbits1 == (most_sig_bit_different addr1 addr2))
 402   where
 403     addr1 = ipv4address cidr1
 404     addr2 = ipv4address cidr2
 405     mbits1 = maskbits cidr1
 406     mbits2 = maskbits cidr2
 407
 408
 409
 410
 411
 412 -- HUnit Tests
 413
 414 test_equality1 :: Test
 415 test_equality1 =
 416     TestCase $ assertEqual "10.1.1.0/23 equals itself" True (cidr1 == cidr1)
 417     where
 418       cidr1 = cidr_from_string "10.1.1.0/23"
 419
 420
 421 test_contains1 :: Test
 422 test_contains1 =
 423     TestCase $ assertEqual "10.1.1.0/23 contains 10.1.1.0/24" True (cidr1 `contains` cidr2)
 424     where
 425       cidr1 = cidr_from_string "10.1.1.0/23"
 426       cidr2 = cidr_from_string "10.1.1.0/24"
 427
 428
 429 test_contains2 :: Test
 430 test_contains2 =
 431     TestCase $ assertEqual "10.1.1.0/23 contains itself" True (cidr1 `contains` cidr1)
 432     where
 433       cidr1 = cidr_from_string "10.1.1.0/23"
 434
 435
 436 test_contains_proper1 :: Test
 437 test_contains_proper1 =
 438     TestCase $ assertEqual "10.1.1.0/23 contains 10.1.1.0/24 properly" True (cidr1 `contains_proper` cidr2)
 439     where
 440       cidr1 = cidr_from_string "10.1.1.0/23"
 441       cidr2 = cidr_from_string "10.1.1.0/24"
 442
 443
 444 test_contains_proper2 :: Test
 445 test_contains_proper2 =
 446     TestCase $ assertEqual "10.1.1.0/23 does not contain itself properly" False (cidr1 `contains_proper` cidr1)
 447     where
 448       cidr1 = cidr_from_string "10.1.1.0/23"
 449
 450
 451 test_adjacent1 :: Test
 452 test_adjacent1 =
 453     TestCase $ assertEqual "10.1.0.0/24 is adjacent to 10.1.1.0/24" True (cidr1 `adjacent` cidr2)
 454     where
 455       cidr1 = cidr_from_string "10.1.0.0/24"
 456       cidr2 = cidr_from_string "10.1.1.0/24"
 457
 458
 459 test_adjacent2 :: Test
 460 test_adjacent2 =
 461     TestCase $ assertEqual "10.1.0.0/23 is not adjacent to 10.1.0.0/24" False (cidr1 `adjacent` cidr2)
 462     where
 463       cidr1 = cidr_from_string "10.1.0.0/23"
 464       cidr2 = cidr_from_string "10.1.0.0/24"
 465
 466
 467 test_adjacent3 :: Test
 468 test_adjacent3 =
 469     TestCase $ assertEqual "10.1.0.0/24 is not adjacent to 10.2.5.0/24" False (cidr1 `adjacent` cidr2)
 470     where
 471       cidr1 = cidr_from_string "10.1.0.0/24"
 472       cidr2 = cidr_from_string "10.2.5.0/24"
 473
 474
 475 test_adjacent4 :: Test
 476 test_adjacent4 =
 477     TestCase $ assertEqual "10.1.1.0/24 is not adjacent to 10.1.2.0/24" False (cidr1 `adjacent` cidr2)
 478     where
 479       cidr1 = cidr_from_string "10.1.1.0/24"
 480       cidr2 = cidr_from_string "10.1.2.0/24"
 481
 482
 483 test_combine_contained1 :: Test
 484 test_combine_contained1 =
 485     TestCase $ assertEqual "10.0.0.0/8, 10.1.0.0/16, and 10.1.1.0/24 combine to 10.0.0.0/8" expected_cidrs (combine_contained test_cidrs)
 486     where
 487       cidr1 = cidr_from_string "10.0.0.0/8"
 488       cidr2 = cidr_from_string "10.1.0.0/16"
 489       cidr3 = cidr_from_string "10.1.1.0/24"
 490       expected_cidrs = [cidr1]
 491       test_cidrs = [cidr1, cidr2, cidr3]
 492
 493
 494 test_combine_contained2 :: Test
 495 test_combine_contained2 =
 496     TestCase $ assertEqual "192.168.3.0/23 does not contain 192.168.1.0/24" [cidr1, cidr2] (combine_contained [cidr1, cidr2])
 497     where
 498       cidr1 = cidr_from_string "192.168.3.0/23"
 499       cidr2 = cidr_from_string "192.168.1.0/24"
 500
 501
 502 test_combine_all1 :: Test
 503 test_combine_all1 =
 504     TestCase $ assertEqual "10.0.0.0/24 is adjacent to 10.0.1.0/24 and 10.0.3.0/23 contains 10.0.2.0/24" expected_cidrs (combine_all test_cidrs)
 505     where
 506       cidr1 = cidr_from_string "10.0.0.0/24"
 507       cidr2 = cidr_from_string "10.0.1.0/24"
 508       cidr3 = cidr_from_string "10.0.2.0/24"
 509       cidr4 = cidr_from_string "10.0.3.0/23"
 510       cidr5 = cidr_from_string "10.0.0.0/23"
 511       expected_cidrs = [cidr4, cidr5]
 512       test_cidrs = [cidr1, cidr2, cidr3, cidr4]
 513
 514
 515 test_combine_all2 :: Test
 516 test_combine_all2 =
 517     TestCase $ assertEqual "127.0.0.1/32 combines with itself recursively" expected_cidrs (combine_all test_cidrs)
 518     where
 519       cidr1 = cidr_from_string "127.0.0.1/32"
 520       expected_cidrs = [cidr1]
 521       test_cidrs = [cidr1, cidr1, cidr1, cidr1, cidr1]
 522
 523
 524 cidr_tests :: [Test]
 525 cidr_tests = [ test_equality1,
 526                test_contains1,
 527                test_contains2,
 528                test_contains_proper1,
 529                test_contains_proper2,
 530                test_adjacent1,
 531                test_adjacent2,
 532                test_adjacent3,
 533                test_adjacent4,
 534                test_combine_contained1,
 535                test_combine_contained2,
 536                test_combine_all1,
 537                test_combine_all2
 538              ]
 539
 540
 541 -- QuickCheck Tests
 542 prop_all_cidrs_contain_themselves :: Cidr -> Bool
 543 prop_all_cidrs_contain_themselves cidr1 = cidr1 `contains` cidr1
 544
 545
 546 -- If cidr1 properly contains cidr2, then by definition cidr2
 547 -- does not properly contain cidr1.
 548 prop_contains_proper_intransitive :: Cidr -> Cidr -> Property
 549 prop_contains_proper_intransitive cidr1 cidr2 =
 550     (cidr1 `contains_proper` cidr2) ==>
 551       (not (cidr2 `contains_proper` cidr1))