+ unique_cidrs = nub cidr_combinations
+ cidr_combinations =
+ cidrs ++ (catMaybes [ (combine_adjacent x y) | x <- cidrs, y <- cidrs ])
+
+
+-- | Take a list of CIDR ranges and filter out all of the ones that
+-- are contained entirelt within some other range in the list.
+combine_contained :: [Cidr] -> [Cidr]
+combine_contained cidrs =
+ filter (not . (redundant cidrs)) cidrs
+
+
+-- | If the two Cidrs are not adjacent, return Cidr.None. Otherwise,
+-- decrement the maskbits of cidr1 and return that; it will contain
+-- both cidr1 and cidr2.
+combine_adjacent :: Cidr -> Cidr -> Maybe Cidr
+combine_adjacent cidr1 cidr2
+ | not (adjacent cidr1 cidr2) = Nothing
+ | (maskbits cidr1 == Zero) = Nothing
+ | otherwise = Just $ cidr1 { maskbits = pred (maskbits cidr1) }
+
+
+
+-- | Determine whether or not two CIDR ranges are adjacent. If two
+-- ranges lie consecutively within the IP space, they can be
+-- combined. For example, 10.1.0.0/24 and 10.0.1.0/24 are adjacent,
+-- and can be combined in to 10.1.0.0/23.
+adjacent :: Cidr -> Cidr -> Bool
+adjacent cidr1 cidr2
+ | mbits1 /= mbits2 = False
+ | mbits1 == Maskbits.Zero = False -- They're equal.
+ | otherwise = (mbits1 == (most_sig_bit_different addr1 addr2))
+ where
+ addr1 = ipv4address cidr1
+ addr2 = ipv4address cidr2
+ mbits1 = maskbits cidr1
+ mbits2 = maskbits cidr2
+
+
+enumerate :: Cidr -> [IPv4Address]
+enumerate cidr = [(min_host cidr)..(max_host cidr)]
+
+
+-- | Replace any masked bits in this CIDR's IPv4Address with zeros.
+normalize :: Cidr -> Cidr
+normalize (Cidr addr mask) =
+ Cidr nrml_addr mask
+ where
+ nrml_addr = apply_mask addr mask B.Zero
+
+-- Test lists.
+cidr_tests :: TestTree
+cidr_tests =
+ testGroup "CIDR Tests" [
+ test_enumerate,
+ test_min_host1,
+ test_max_host1,
+ test_equality1,
+ test_contains1,
+ test_contains2,
+ test_contains_proper1,
+ test_contains_proper2,
+ test_adjacent1,
+ test_adjacent2,
+ test_adjacent3,
+ test_adjacent4,
+ test_combine_contained1,
+ test_combine_contained2,
+ test_combine_all1,
+ test_combine_all2,
+ test_combine_all3,
+ test_normalize1,
+ test_normalize2,
+ test_normalize3,
+ test_big_networks_come_first ]
+
+cidr_properties :: TestTree
+cidr_properties =
+ testGroup "CIDR Properties" [
+ prop_all_cidrs_contain_themselves,
+ prop_contains_proper_antisymmetric,
+ prop_normalize_idempotent,
+ prop_normalize_preserves_equality,
+ prop_ord_instance_antisymmetric,
+ prop_ord_instance_reflexive,
+ prop_ord_instance_transitive,
+ prop_ord_uses_addr_when_masks_equal,
+ prop_ord_uses_mask_when_addrs_equal,
+ prop_ord_and_contains_disagree,
+ prop_ord_minimum,
+ prop_ord_maximum ]
+
+
+-- HUnit Tests
+test_enumerate :: TestTree
+test_enumerate =
+ testCase desc $ actual @?= expected
+ where
+ desc = "192.168.0.240/30 is enumerated correctly"
+ oct1 = toEnum 192 :: Octet
+ oct2 = toEnum 168 :: Octet
+ oct3 = minBound :: Octet
+ mk_ip = IPv4Address oct1 oct2 oct3
+ addr1 = mk_ip $ toEnum 240
+ addr2 = mk_ip $ toEnum 241
+ addr3 = mk_ip $ toEnum 242
+ addr4 = mk_ip $ toEnum 243
+ expected = [addr1, addr2, addr3, addr4]
+ actual = enumerate (read "192.168.0.240/30" :: Cidr)
+
+test_min_host1 :: TestTree
+test_min_host1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "The minimum host in 10.0.0.0/24 is 10.0.0.0"
+ actual = show $ min_host (read "10.0.0.0/24" :: Cidr)
+ expected = "10.0.0.0"
+
+
+test_max_host1 :: TestTree
+test_max_host1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "The maximum host in 10.0.0.0/24 is 10.0.0.255"
+ actual = show $ max_host (read "10.0.0.0/24" :: Cidr)
+ expected = "10.0.0.255"
+
+
+test_equality1 :: TestTree
+test_equality1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.1.0/23 equals itself"
+ actual = read "10.1.1.0/23" :: Cidr
+ expected = read "10.1.1.0/23" :: Cidr
+
+
+test_contains1 :: TestTree
+test_contains1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.1.0/23 contains 10.1.1.0/24"
+ cidr1 = read "10.1.1.0/23" :: Cidr
+ cidr2 = read "10.1.1.0/24" :: Cidr
+ expected = True
+ actual = cidr1 `contains` cidr2
+
+
+test_contains2 :: TestTree
+test_contains2 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.1.0/23 contains itself"
+ cidr1 = read "10.1.1.0/23" :: Cidr
+ expected = True
+ actual = cidr1 `contains` cidr1
+
+
+test_contains_proper1 :: TestTree
+test_contains_proper1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.1.0/23 contains 10.1.1.0/24 properly"
+ cidr1 = read "10.1.1.0/23" :: Cidr
+ cidr2 = read "10.1.1.0/24" :: Cidr
+ expected = True
+ actual = cidr1 `contains_proper` cidr2
+
+
+test_contains_proper2 :: TestTree
+test_contains_proper2 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.1.0/23 does not contain itself properly"
+ cidr1 = read "10.1.1.0/23" :: Cidr
+ expected = False
+ actual = cidr1 `contains_proper` cidr1
+
+
+test_adjacent1 :: TestTree
+test_adjacent1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.0.0/24 is adjacent to 10.1.1.0/24"
+ cidr1 = read "10.1.0.0/24" :: Cidr
+ cidr2 = read "10.1.1.0/24" :: Cidr
+ expected = True
+ actual = cidr1 `adjacent` cidr2
+
+
+test_adjacent2 :: TestTree
+test_adjacent2 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.0.0/23 is not adjacent to 10.1.0.0/24"
+ cidr1 = read "10.1.0.0/23" :: Cidr
+ cidr2 = read "10.1.0.0/24" :: Cidr
+ expected = False
+ actual = cidr1 `adjacent` cidr2
+
+
+test_adjacent3 :: TestTree
+test_adjacent3 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.0.0/24 is not adjacent to 10.2.5.0/24"
+ cidr1 = read "10.1.0.0/24" :: Cidr
+ cidr2 = read "10.2.5.0/24" :: Cidr
+ expected = False
+ actual = cidr1 `adjacent` cidr2
+
+
+test_adjacent4 :: TestTree
+test_adjacent4 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.1.1.0/24 is not adjacent to 10.1.2.0/24"
+ cidr1 = read "10.1.1.0/24" :: Cidr
+ cidr2 = read "10.1.2.0/24" :: Cidr
+ expected = False
+ actual = cidr1 `adjacent` cidr2
+
+test_combine_contained1 :: TestTree
+test_combine_contained1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.0.0.0/8, 10.1.0.0/16, and 10.1.1.0/24 combine to 10.0.0.0/8"
+ cidr1 = read "10.0.0.0/8" :: Cidr
+ cidr2 = read "10.1.0.0/16" :: Cidr
+ cidr3 = read "10.1.1.0/24" :: Cidr
+ test_cidrs = [cidr1, cidr2, cidr3]
+ expected = [cidr1]
+ actual = combine_contained test_cidrs
+
+test_combine_contained2 :: TestTree
+test_combine_contained2 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "192.168.3.0/23 does not contain 192.168.1.0/24"
+ cidr1 = read "192.168.3.0/23" :: Cidr
+ cidr2 = read "192.168.1.0/24" :: Cidr
+ expected = [cidr1, cidr2]
+ actual = combine_contained [cidr1, cidr2]
+
+
+test_combine_all1 :: TestTree
+test_combine_all1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "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"
+ cidr1 = read "10.0.0.0/24" :: Cidr
+ cidr2 = read "10.0.1.0/24" :: Cidr
+ cidr3 = read "10.0.2.0/24" :: Cidr
+ cidr4 = read "10.0.3.0/23" :: Cidr
+ cidr5 = read "10.0.0.0/23" :: Cidr
+ test_cidrs = [cidr1, cidr2, cidr3, cidr4, cidr5]
+ expected = [read "10.0.0.0/22" :: Cidr]
+ actual = combine_all test_cidrs
+
+
+test_combine_all2 :: TestTree
+test_combine_all2 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "127.0.0.1/32 combines with itself recursively"
+ cidr1 = read "127.0.0.1/32" :: Cidr
+ test_cidrs = [cidr1, cidr1, cidr1, cidr1, cidr1]
+ expected = [cidr1]
+ actual = combine_all test_cidrs
+
+
+test_combine_all3 :: TestTree
+test_combine_all3 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.0.0.16, 10.0.0.17, 10.0.0.18, and "
+ ++ "10.0.0.19 get combined into 10.0.0.16/30"
+ cidr1 = read "10.0.0.16/32" :: Cidr
+ cidr2 = read "10.0.0.17/32" :: Cidr
+ cidr3 = read "10.0.0.18/32" :: Cidr
+ cidr4 = read "10.0.0.19/32" :: Cidr
+ test_cidrs = [cidr1, cidr2, cidr3, cidr4]
+ expected = [read "10.0.0.16/30" :: Cidr]
+ actual = combine_all test_cidrs
+
+test_normalize1 :: TestTree
+test_normalize1 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "127.0.0.1/8 normalized is 127.0.0.0/8"
+ expected = read "127.0.0.0/8" :: Cidr
+ actual = normalize (read "127.0.0.1/8" :: Cidr)
+
+
+test_normalize2 :: TestTree
+test_normalize2 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "192.168.1.101/24 normalized is 192.168.1.0/24"
+ expected = read "192.168.1.0/24" :: Cidr
+ actual = normalize (read "192.168.1.101/24" :: Cidr)
+
+test_normalize3 :: TestTree
+test_normalize3 =
+ testCase desc $ actual @?= expected
+ where
+ desc = "10.10.10.10/22 normalized is 10.10.8.0/22"
+ expected = read "10.10.8.0/22" :: Cidr
+ actual = normalize (read "10.10.10.10/22" :: Cidr)
+
+-- | Test a stated property of the Ord instance, namely that the big
+-- network 127.0.0.1/8 comes before the small network 127.0.0.1/32.
+test_big_networks_come_first :: TestTree
+test_big_networks_come_first =
+ testCase desc $ actual @?= expected
+ where
+ desc = "127.0.0.1/8 comes before 127.0.0.1/32"
+ big = read "127.0.0.1/8" :: Cidr
+ small = read "127.0.0.1/32" :: Cidr
+ expected = True
+ actual = big <= small -- not a typo
+
+-- QuickCheck Tests
+prop_all_cidrs_contain_themselves :: TestTree
+prop_all_cidrs_contain_themselves =
+ testProperty "All CIDRs contain themselves" prop
+ where
+ prop :: Cidr -> Bool
+ prop cidr1 = cidr1 `contains` cidr1
+
+
+-- If cidr1 properly contains cidr2, then by definition cidr2
+-- does not properly contain cidr1.
+prop_contains_proper_antisymmetric :: TestTree
+prop_contains_proper_antisymmetric =
+ testProperty "CIDR proper containment is an antisymmetric relation" prop
+ where
+ prop :: Cidr -> Cidr -> Property
+ prop cidr1 cidr2 =
+ (cidr1 `contains_proper` cidr2) ==>
+ (not (cidr2 `contains_proper` cidr1))
+
+
+-- Running "normalize" a second time shouldn't do anything.
+prop_normalize_idempotent :: TestTree
+prop_normalize_idempotent =
+ testProperty "The CIDR \"normalize\" function is idempotent" prop
+ where
+ prop :: Cidr -> Bool
+ prop cidr = (normalize cidr) == (normalize (normalize cidr))
+
+-- Normalization should not affect equality of two CIDRs.
+prop_normalize_preserves_equality :: TestTree
+prop_normalize_preserves_equality =
+ testProperty "The CIDR \"normalize\" function preserves equality" prop
+ where
+ prop :: Cidr -> Cidr -> Bool
+ prop cidr1 cidr2 = (cidr1 == cidr2) == (normalize cidr1 == normalize cidr2)
+
+
+prop_ord_instance_reflexive :: TestTree
+prop_ord_instance_reflexive =
+ testProperty "The CIDR order is reflexive" prop
+ where
+ prop :: Cidr -> Bool
+ prop cidr = cidr <= cidr
+
+
+prop_ord_instance_transitive :: TestTree
+prop_ord_instance_transitive =
+ testProperty "The CIDR order is transitive" prop
+ where
+ prop :: Cidr -> Cidr -> Cidr -> Property
+ prop cidr1 cidr2 cidr3 =
+ (cidr1 <= cidr2 && cidr2 <= cidr3) ==> cidr1 <= cidr3
+
+-- This is how Eq is currently implemented, but it is useful to have
+-- around in case that changes. Try fewer instances of this than usual
+-- because it's a rare condition.
+prop_ord_instance_antisymmetric :: TestTree
+prop_ord_instance_antisymmetric =
+ localOption (QuickCheckTests 500) $
+ testProperty "The CIDR order is antisymmetric" prop
+ where
+ prop :: Cidr -> Cidr -> Property
+ prop cidr1 cidr2 =
+ (cidr1 <= cidr2 && cidr2 <= cidr1) ==> cidr1 == cidr2
+
+
+-- When comparing two CIDRs with the same mask, the comparison
+-- should be numeric (i.e. whatever the IPv4Address does).
+-- Of course, we have to normalize first.
+prop_ord_uses_addr_when_masks_equal :: TestTree
+prop_ord_uses_addr_when_masks_equal =
+ testProperty "The CIDR order is the IPv4Address order for equal masks" prop
+ where
+ prop :: Cidr -> Cidr -> Property
+ prop cidr1 cidr2 =
+ (mask1 == mask2) ==> (cidr1 <= cidr2) == (addr1 <= addr2)
+ where
+ (Cidr addr1 mask1) = normalize cidr1
+ (Cidr addr2 mask2) = normalize cidr2
+
+
+-- If we have two CIDRs whose normalized addresses agree, then we want
+-- to use the mask order, i.e. that big networks come before small
+-- networks. This disagrees with containment order.
+prop_ord_uses_mask_when_addrs_equal :: TestTree
+prop_ord_uses_mask_when_addrs_equal =
+ localOption (QuickCheckTests 500) $
+ testProperty "The CIDR order is by mask when the addresses agree" prop
+ where
+ prop :: Cidr -> Cidr -> Property
+ prop cidr1 cidr2 =
+ (addr1 == addr2) ==> (cidr1 <= cidr2) == (mask1 <= mask2)
+ where
+ (Cidr addr1 mask1) = normalize cidr1
+ (Cidr addr2 mask2) = normalize cidr2
+
+
+-- Big networks come first.
+prop_ord_and_contains_disagree :: TestTree
+prop_ord_and_contains_disagree =
+ testProperty "The CIDR order disagrees with containment" prop
+ where
+ prop :: Cidr -> Cidr -> Property
+ prop cidr1 cidr2 = (cidr1 `contains` cidr2) ==> (cidr1 <= cidr2)
+
+
+-- The biggest network always comes first.
+prop_ord_minimum :: TestTree
+prop_ord_minimum =
+ testProperty "The CIDR order has 0.0.0.0/0 as a minimum" prop
+ where
+ min_cidr = read "0.0.0.0/0" :: Cidr
+ prop :: Cidr -> Bool
+ prop cidr = min_cidr <= cidr
+
+
+-- The CIDR order also has a maximum.
+prop_ord_maximum :: TestTree
+prop_ord_maximum =
+ testProperty "The CIDR order has 255.255.255.255/32 as a maximum" prop
+ where
+ max_cidr = read "255.255.255.255/32" :: Cidr
+ prop :: Cidr -> Bool
+ prop cidr = max_cidr >= cidr