From: Michael Orlitzky Date: Tue, 27 Dec 2011 03:33:25 +0000 (-0500) Subject: Rewrite everything to use Maybe instead of None constructors. X-Git-Tag: 0.0.1~13 X-Git-Url: https://gitweb.michael.orlitzky.com/?a=commitdiff_plain;h=e8b41784eaa68049f7a7354916c9c9920050db70;p=hath.git Rewrite everything to use Maybe instead of None constructors. Convert comments to Haddock-style docs in many places. Whitespace cleanup. --- diff --git a/src/Bit.hs b/src/Bit.hs index a4241bc..128b6f6 100644 --- a/src/Bit.hs +++ b/src/Bit.hs @@ -1,29 +1,35 @@ -module Bit where +-- | The Bit module contains the Bit data type, which is essentially a +-- renamed Boolean, and some convenience functions. +module Bit +where -import Test.QuickCheck +import Test.QuickCheck ( + Arbitrary, + arbitrary, + elements + ) -data Bit = None | Zero | One - deriving (Eq) +data Bit = Zero | One + deriving (Eq) instance Show Bit where - show None = "None" - show Zero = "0" - show One = "1" + show Zero = "0" + show One = "1" instance Arbitrary Bit where - arbitrary = elements [ Zero, One ] + arbitrary = elements [ Zero, One ] +-- | Convert a Bit to an Int. bit_to_int :: Bit -> Int -bit_to_int None = -1 bit_to_int Zero = 0 bit_to_int One = 1 --- If we are passed a '0' or '1', convert it appropriately. Otherwise, --- default to None. -bit_from_char :: Char -> Bit -bit_from_char '0' = Zero -bit_from_char '1' = One -bit_from_char _ = None +-- | If we are passed a '0' or '1', convert it +-- appropriately. Otherwise, default to Nothing. +bit_from_char :: Char -> Maybe Bit +bit_from_char '0' = Just Zero +bit_from_char '1' = Just One +bit_from_char _ = Nothing diff --git a/src/Cidr.hs b/src/Cidr.hs index 422a0ad..826c862 100644 --- a/src/Cidr.hs +++ b/src/Cidr.hs @@ -18,6 +18,7 @@ module Cidr ) where import Data.List (nubBy) +import Data.Maybe (catMaybes, fromJust) import Test.HUnit import Test.QuickCheck @@ -29,13 +30,12 @@ import Maskbits import Octet -data Cidr = None | Cidr { ipv4address :: IPv4Address, - maskbits :: Maskbits } +data Cidr = Cidr { ipv4address :: IPv4Address, + maskbits :: Maskbits } instance Show Cidr where - show Cidr.None = "None" show cidr = (show (ipv4address cidr)) ++ "/" ++ (show (maskbits cidr)) @@ -53,56 +53,45 @@ instance Eq Cidr where -- Two CIDR ranges are equivalent if they have the same network bits -- and the masks are the same. equivalent :: Cidr -> Cidr -> Bool -equivalent Cidr.None Cidr.None = True -equivalent Cidr.None _ = False -equivalent _ Cidr.None = False equivalent (Cidr addr1 mbits1) (Cidr addr2 mbits2) = (mbits1 == mbits2) && ((apply_mask addr1 mbits1 B.Zero) == (apply_mask addr2 mbits2 B.Zero)) -- Returns the mask portion of a CIDR address. That is, everything -- after the trailing slash. -maskbits_from_cidr_string :: String -> Maskbits +maskbits_from_cidr_string :: String -> Maybe Maskbits maskbits_from_cidr_string s - | length partlist == 2 = maskbits_from_string (partlist !! 1) - | otherwise = Maskbits.None - where - partlist = (splitWith (`elem` "/") s) + | length partlist == 2 = maskbits_from_string (partlist !! 1) + | otherwise = Nothing + where + partlist = (splitWith (`elem` "/") s) --- Takes an IP address String in CIDR notation, and returns a list of --- its octets (as Ints). +-- | Takes an IP address String in CIDR notation, and returns a list +-- of its octets (as Ints). octets_from_cidr_string :: String -> [Octet] octets_from_cidr_string s = - map octet_from_string (take 4 (splitWith (`elem` "./") s)) + catMaybes $ map octet_from_string (take 4 (splitWith (`elem` "./") s)) -cidr_from_string :: String -> Cidr -cidr_from_string s - | addr == IPv4Address.None = Cidr.None - | mbits == Maskbits.None = Cidr.None - | otherwise = Cidr addr mbits - where - addr = ipv4address_from_octets (oct1) (oct2) (oct3) (oct4) - oct1 = (octs !! 0) - oct2 = (octs !! 1) - oct3 = (octs !! 2) - oct4 = (octs !! 3) - octs = octets_from_cidr_string s - mbits = maskbits_from_cidr_string s +-- | Return Nothing if we can't parse both maskbits and octets from +-- the string. +cidr_from_string :: String -> Maybe Cidr +cidr_from_string s = + case (octets_from_cidr_string s) of + [oct1, oct2, oct3, oct4] -> + case (maskbits_from_cidr_string s) of + Just mbits -> + Just $ Cidr (IPv4Address oct1 oct2 oct3 oct4) mbits + _ -> Nothing + _ -> Nothing min_host :: Cidr -> IPv4Address -min_host Cidr.None = IPv4Address.None -min_host (Cidr IPv4Address.None _) = IPv4Address.None -min_host (Cidr _ Maskbits.None) = IPv4Address.None min_host (Cidr addr mask) = apply_mask addr mask B.Zero max_host :: Cidr -> IPv4Address -max_host Cidr.None = IPv4Address.None -max_host (Cidr IPv4Address.None _) = IPv4Address.None -max_host (Cidr _ Maskbits.None) = IPv4Address.None max_host (Cidr addr mask) = apply_mask addr mask B.One @@ -132,51 +121,45 @@ max_octet4 cidr = octet4 (max_host cidr) --- Return true if the first argument (a CIDR range) contains the --- second (another CIDR range). There are a lot of ways we can be fed --- junk here. For lack of a better alternative, just return False when --- we are given nonsense. -contains :: Cidr -> Cidr -> Bool -contains Cidr.None _ = False -contains _ Cidr.None = False -contains (Cidr _ Maskbits.None) _ = False -contains (Cidr IPv4Address.None _) _ = False -contains _ (Cidr _ Maskbits.None) = False -contains _ (Cidr IPv4Address.None _) = False - --- If the number of bits in the network part of the first address is --- larger than the number of bits in the second, there is no way that --- the first range can contain the second. For, if the number of --- network bits is larger, then the number of host bits must be --- smaller, and if cidr1 has fewer hosts than cidr2, cidr1 most --- certainly does not contain cidr2. +-- | Return true if the first argument (a CIDR range) contains the +-- second (another CIDR range). There are a lot of ways we can be +-- fed junk here. For lack of a better alternative, just return +-- False when we are given nonsense. +-- +-- If the number of bits in the network part of the first address is +-- larger than the number of bits in the second, there is no way +-- that the first range can contain the second. For, if the number +-- of network bits is larger, then the number of host bits must be +-- smaller, and if cidr1 has fewer hosts than cidr2, cidr1 most +-- certainly does not contain cidr2. -- --- On the other hand, if the first argument (cidr1) has fewer (or the --- same number of) network bits as the second, it can contain the --- second. In this case, we need to check that every host in cidr2 is --- contained in cidr1. If a host in cidr2 is contained in cidr1, then --- at least mbits1 of an address in cidr2 will match cidr1. For --- example, +-- On the other hand, if the first argument (cidr1) has fewer (or +-- the same number of) network bits as the second, it can contain +-- the second. In this case, we need to check that every host in +-- cidr2 is contained in cidr1. If a host in cidr2 is contained in +-- cidr1, then at least mbits1 of an address in cidr2 will match +-- cidr1. For example, -- --- cidr1 = 192.168.1.0/23, cidr2 = 192.168.1.100/24 +-- cidr1 = 192.168.1.0/23, cidr2 = 192.168.1.100/24 -- --- Here, cidr2 contains all of 192.168.1.0 through --- 192.168.1.255. However, cidr1 contains BOTH 192.168.0.0 through --- 192.168.0.255 and 192.168.1.0 through 192.168.1.255. In essence, --- what we want to check is that cidr2 "begins with" something that --- cidr1 CAN begin with. Since cidr1 can begin with 192.168.1, and --- cidr2 DOES, cidr1 contains cidr2.. +-- Here, cidr2 contains all of 192.168.1.0 through +-- 192.168.1.255. However, cidr1 contains BOTH 192.168.0.0 through +-- 192.168.0.255 and 192.168.1.0 through 192.168.1.255. In essence, +-- what we want to check is that cidr2 "begins with" something that +-- cidr1 CAN begin with. Since cidr1 can begin with 192.168.1, and +-- cidr2 DOES, cidr1 contains cidr2.. -- --- The way that we check this is to apply cidr1's mask to cidr2's --- address and see if the result is the same as cidr1's mask applied --- to cidr1's address. +-- The way that we check this is to apply cidr1's mask to cidr2's +-- address and see if the result is the same as cidr1's mask applied +-- to cidr1's address. -- +contains :: Cidr -> Cidr -> Bool contains (Cidr addr1 mbits1) (Cidr addr2 mbits2) - | mbits1 > mbits2 = False - | otherwise = addr1masked == addr2masked - where - addr1masked = apply_mask addr1 mbits1 B.Zero - addr2masked = apply_mask addr2 mbits1 B.Zero + | mbits1 > mbits2 = False + | otherwise = addr1masked == addr2masked + where + addr1masked = apply_mask addr1 mbits1 B.Zero + addr2masked = apply_mask addr2 mbits1 B.Zero contains_proper :: Cidr -> Cidr -> Bool @@ -184,59 +167,56 @@ contains_proper cidr1 cidr2 = (cidr1 `contains` cidr2) && (not (cidr2 `contains` cidr1)) --- A CIDR range is redundant (with respect to the given list) if --- another CIDR range in that list properly contains it. +-- | A CIDR range is redundant (with respect to the given list) if +-- another CIDR range in that list properly contains it. redundant :: [Cidr] -> Cidr -> Bool redundant cidrlist cidr = any ((flip contains_proper) cidr) cidrlist --- First, we look at all possible pairs of cidrs, and combine the --- adjacent ones in to a new list. Then, we concatenate that list with --- the original one, and filter out all of the redundancies. If two --- adjacent Cidrs are combined into a larger one, they will be removed --- in the second step since the larger Cidr must contain the smaller --- two. +-- | First, we look at all possible pairs of cidrs, and combine the +-- adjacent ones in to a new list. Then, we concatenate that list +-- with the original one, and filter out all of the redundancies. If +-- two adjacent Cidrs are combined into a larger one, they will be +-- removed in the second step since the larger Cidr must contain the +-- smaller two. -- --- Once this is done, we see whether or not the result is different --- than the argument that was passed in. If nothing changed, we're --- done and return the list that was passed to us. However, if --- something changed, we recurse and try to combine the list again. +-- Once this is done, we see whether or not the result is different +-- than the argument that was passed in. If nothing changed, we're +-- done and return the list that was passed to us. However, if +-- something changed, we recurse and try to combine the list again. combine_all :: [Cidr] -> [Cidr] combine_all cidrs | cidrs == (combine_contained unique_cidrs) = cidrs | otherwise = combine_all (combine_contained unique_cidrs) where - unique_cidrs = nubBy equivalent valid_cidr_combinations - valid_cidr_combinations = filter (/= Cidr.None) cidr_combinations + unique_cidrs = nubBy equivalent cidr_combinations cidr_combinations = - cidrs ++ [ (combine_adjacent x y) | x <- cidrs, y <- cidrs ] + 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. +-- | 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 + 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 -> Cidr +-- | 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) = Cidr.None - | (maskbits cidr1 == Zero) = Cidr.None - | otherwise = cidr1 { maskbits = decrement (maskbits cidr1) } + | not (adjacent cidr1 cidr2) = Nothing + | (maskbits cidr1 == Zero) = Nothing + | otherwise = Just $ cidr1 { maskbits = decrement (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. +-- | 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 Cidr.None _ = False -adjacent _ Cidr.None = False adjacent cidr1 cidr2 | mbits1 /= mbits2 = False | mbits1 == Maskbits.Zero = False -- They're equal. @@ -255,140 +235,201 @@ adjacent cidr1 cidr2 test_min_host1 :: Test test_min_host1 = - TestCase $ assertEqual "The minimum host in 10.0.0.0/24 is 10.0.0.0" expected actual - where - actual = show $ min_host (cidr_from_string "10.0.0.0/24") - expected = "10.0.0.0" + TestCase $ assertEqual "The minimum host in 10.0.0.0/24 is 10.0.0.0" + expected + actual + where + actual = show $ min_host (fromJust $ cidr_from_string "10.0.0.0/24") + expected = "10.0.0.0" test_max_host1 :: Test test_max_host1 = - TestCase $ assertEqual "The maximum host in 10.0.0.0/24 is 10.0.0.255" expected actual - where - actual = show $ max_host (cidr_from_string "10.0.0.0/24") - expected = "10.0.0.255" + TestCase $ assertEqual "The maximum host in 10.0.0.0/24 is 10.0.0.255" + expected + actual + where + actual = show $ max_host (fromJust $ cidr_from_string "10.0.0.0/24") + expected = "10.0.0.255" test_equality1 :: Test test_equality1 = - TestCase $ assertEqual "10.1.1.0/23 equals itself" True (cidr1 == cidr1) - where - cidr1 = cidr_from_string "10.1.1.0/23" + TestCase $ + assertEqual + "10.1.1.0/23 equals itself" + True + (cidr1 == cidr1) + where + cidr1 = fromJust $ cidr_from_string "10.1.1.0/23" test_contains1 :: Test test_contains1 = - TestCase $ assertEqual "10.1.1.0/23 contains 10.1.1.0/24" True (cidr1 `contains` cidr2) - where - cidr1 = cidr_from_string "10.1.1.0/23" - cidr2 = cidr_from_string "10.1.1.0/24" + TestCase $ + assertEqual + "10.1.1.0/23 contains 10.1.1.0/24" + True + (cidr1 `contains` cidr2) + where + cidr1 = fromJust $ cidr_from_string "10.1.1.0/23" + cidr2 = fromJust $ cidr_from_string "10.1.1.0/24" test_contains2 :: Test test_contains2 = - TestCase $ assertEqual "10.1.1.0/23 contains itself" True (cidr1 `contains` cidr1) - where - cidr1 = cidr_from_string "10.1.1.0/23" + TestCase $ + assertEqual + "10.1.1.0/23 contains itself" + True + (cidr1 `contains` cidr1) + where + cidr1 = fromJust $ cidr_from_string "10.1.1.0/23" test_contains_proper1 :: Test test_contains_proper1 = - TestCase $ assertEqual "10.1.1.0/23 contains 10.1.1.0/24 properly" True (cidr1 `contains_proper` cidr2) - where - cidr1 = cidr_from_string "10.1.1.0/23" - cidr2 = cidr_from_string "10.1.1.0/24" + TestCase $ + assertEqual + "10.1.1.0/23 contains 10.1.1.0/24 properly" + True + (cidr1 `contains_proper` cidr2) + where + cidr1 = fromJust $ cidr_from_string "10.1.1.0/23" + cidr2 = fromJust $ cidr_from_string "10.1.1.0/24" test_contains_proper2 :: Test test_contains_proper2 = - TestCase $ assertEqual "10.1.1.0/23 does not contain itself properly" False (cidr1 `contains_proper` cidr1) - where - cidr1 = cidr_from_string "10.1.1.0/23" + TestCase $ + assertEqual + "10.1.1.0/23 does not contain itself properly" + False + (cidr1 `contains_proper` cidr1) + where + cidr1 = fromJust $ cidr_from_string "10.1.1.0/23" test_adjacent1 :: Test test_adjacent1 = - TestCase $ assertEqual "10.1.0.0/24 is adjacent to 10.1.1.0/24" True (cidr1 `adjacent` cidr2) - where - cidr1 = cidr_from_string "10.1.0.0/24" - cidr2 = cidr_from_string "10.1.1.0/24" + TestCase $ + assertEqual + "10.1.0.0/24 is adjacent to 10.1.1.0/24" + True + (cidr1 `adjacent` cidr2) + where + cidr1 = fromJust $ cidr_from_string "10.1.0.0/24" + cidr2 = fromJust $ cidr_from_string "10.1.1.0/24" test_adjacent2 :: Test test_adjacent2 = - TestCase $ assertEqual "10.1.0.0/23 is not adjacent to 10.1.0.0/24" False (cidr1 `adjacent` cidr2) - where - cidr1 = cidr_from_string "10.1.0.0/23" - cidr2 = cidr_from_string "10.1.0.0/24" + TestCase $ + assertEqual + "10.1.0.0/23 is not adjacent to 10.1.0.0/24" + False + (cidr1 `adjacent` cidr2) + where + cidr1 = fromJust $ cidr_from_string "10.1.0.0/23" + cidr2 = fromJust $ cidr_from_string "10.1.0.0/24" test_adjacent3 :: Test test_adjacent3 = - TestCase $ assertEqual "10.1.0.0/24 is not adjacent to 10.2.5.0/24" False (cidr1 `adjacent` cidr2) - where - cidr1 = cidr_from_string "10.1.0.0/24" - cidr2 = cidr_from_string "10.2.5.0/24" + TestCase $ + assertEqual + "10.1.0.0/24 is not adjacent to 10.2.5.0/24" + False + (cidr1 `adjacent` cidr2) + where + cidr1 = fromJust $ cidr_from_string "10.1.0.0/24" + cidr2 = fromJust $ cidr_from_string "10.2.5.0/24" test_adjacent4 :: Test test_adjacent4 = - TestCase $ assertEqual "10.1.1.0/24 is not adjacent to 10.1.2.0/24" False (cidr1 `adjacent` cidr2) - where - cidr1 = cidr_from_string "10.1.1.0/24" - cidr2 = cidr_from_string "10.1.2.0/24" + TestCase $ + assertEqual + "10.1.1.0/24 is not adjacent to 10.1.2.0/24" + False + (cidr1 `adjacent` cidr2) + where + cidr1 = fromJust $ cidr_from_string "10.1.1.0/24" + cidr2 = fromJust $ cidr_from_string "10.1.2.0/24" test_combine_contained1 :: Test test_combine_contained1 = - 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) - where - cidr1 = cidr_from_string "10.0.0.0/8" - cidr2 = cidr_from_string "10.1.0.0/16" - cidr3 = cidr_from_string "10.1.1.0/24" - expected_cidrs = [cidr1] - test_cidrs = [cidr1, cidr2, cidr3] + 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) + where + cidr1 = fromJust $ cidr_from_string "10.0.0.0/8" + cidr2 = fromJust $ cidr_from_string "10.1.0.0/16" + cidr3 = fromJust $ cidr_from_string "10.1.1.0/24" + expected_cidrs = [cidr1] + test_cidrs = [cidr1, cidr2, cidr3] test_combine_contained2 :: Test test_combine_contained2 = - TestCase $ assertEqual "192.168.3.0/23 does not contain 192.168.1.0/24" [cidr1, cidr2] (combine_contained [cidr1, cidr2]) - where - cidr1 = cidr_from_string "192.168.3.0/23" - cidr2 = cidr_from_string "192.168.1.0/24" + TestCase $ + assertEqual + "192.168.3.0/23 does not contain 192.168.1.0/24" + [cidr1, cidr2] + (combine_contained [cidr1, cidr2]) + where + cidr1 = fromJust $ cidr_from_string "192.168.3.0/23" + cidr2 = fromJust $ cidr_from_string "192.168.1.0/24" test_combine_all1 :: Test test_combine_all1 = - 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) - where - cidr1 = cidr_from_string "10.0.0.0/24" - cidr2 = cidr_from_string "10.0.1.0/24" - cidr3 = cidr_from_string "10.0.2.0/24" - cidr4 = cidr_from_string "10.0.3.0/23" - cidr5 = cidr_from_string "10.0.0.0/23" - expected_cidrs = [cidr_from_string "10.0.0.0/22"] - test_cidrs = [cidr1, cidr2, cidr3, cidr4, cidr5] + 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) + where + cidr1 = fromJust $ cidr_from_string "10.0.0.0/24" + cidr2 = fromJust $ cidr_from_string "10.0.1.0/24" + cidr3 = fromJust $ cidr_from_string "10.0.2.0/24" + cidr4 = fromJust $ cidr_from_string "10.0.3.0/23" + cidr5 = fromJust $ cidr_from_string "10.0.0.0/23" + expected_cidrs = [fromJust $ cidr_from_string "10.0.0.0/22"] + test_cidrs = [cidr1, cidr2, cidr3, cidr4, cidr5] test_combine_all2 :: Test test_combine_all2 = - TestCase $ assertEqual "127.0.0.1/32 combines with itself recursively" expected_cidrs (combine_all test_cidrs) + TestCase $ + assertEqual + "127.0.0.1/32 combines with itself recursively" + expected_cidrs + (combine_all test_cidrs) where - cidr1 = cidr_from_string "127.0.0.1/32" + cidr1 = fromJust $ cidr_from_string "127.0.0.1/32" expected_cidrs = [cidr1] test_cidrs = [cidr1, cidr1, cidr1, cidr1, cidr1] test_combine_all3 :: Test test_combine_all3 = - TestCase $ assertEqual "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" expected_cidrs (combine_all test_cidrs) - where - cidr1 = cidr_from_string "10.0.0.16/32" - cidr2 = cidr_from_string "10.0.0.17/32" - cidr3 = cidr_from_string "10.0.0.18/32" - cidr4 = cidr_from_string "10.0.0.19/32" - expected_cidrs = [cidr_from_string "10.0.0.16/30"] - test_cidrs = [cidr1, cidr2, cidr3, cidr4] + TestCase $ + assertEqual + "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" + expected_cidrs + (combine_all test_cidrs) + where + cidr1 = fromJust $ cidr_from_string "10.0.0.16/32" + cidr2 = fromJust $ cidr_from_string "10.0.0.17/32" + + cidr3 = fromJust $ cidr_from_string "10.0.0.18/32" + cidr4 = fromJust $ cidr_from_string "10.0.0.19/32" + expected_cidrs = [fromJust $ cidr_from_string "10.0.0.16/30"] + test_cidrs = [cidr1, cidr2, cidr3, cidr4] cidr_tests :: [Test] diff --git a/src/IPv4Address.hs b/src/IPv4Address.hs index e72dd59..6153d28 100644 --- a/src/IPv4Address.hs +++ b/src/IPv4Address.hs @@ -1,16 +1,12 @@ module IPv4Address -( ipv4address_from_octets, - ipv4address_tests, - IPv4Address(None), +( ipv4address_tests, + IPv4Address(..), max_address, min_address, most_sig_bit_different, - octet1, - octet2, - octet3, - octet4 ) where +import Data.Maybe (fromJust) import Test.HUnit import Test.QuickCheck @@ -18,154 +14,142 @@ import Maskable import Maskbits import Octet -data IPv4Address = None | IPv4Address { octet1 :: Octet, - octet2 :: Octet, - octet3 :: Octet, - octet4 :: Octet } - deriving (Eq) +data IPv4Address = + IPv4Address { octet1 :: Octet, + octet2 :: Octet, + octet3 :: Octet, + octet4 :: Octet } + deriving (Eq) instance Show IPv4Address where - show IPv4Address.None = "None" - show addr = concat [(show oct1) ++ ".", - (show oct2) ++ ".", - (show oct3) ++ ".", - (show oct4)] - where - oct1 = (octet1 addr) - oct2 = (octet2 addr) - oct3 = (octet3 addr) - oct4 = (octet4 addr) + show addr = concat [(show oct1) ++ ".", + (show oct2) ++ ".", + (show oct3) ++ ".", + (show oct4)] + where + oct1 = (octet1 addr) + oct2 = (octet2 addr) + oct3 = (octet3 addr) + oct4 = (octet4 addr) instance Arbitrary IPv4Address where - arbitrary = do - oct1 <- arbitrary :: Gen Octet - oct2 <- arbitrary :: Gen Octet - oct3 <- arbitrary :: Gen Octet - oct4 <- arbitrary :: Gen Octet - return (IPv4Address oct1 oct2 oct3 oct4) + arbitrary = do + oct1 <- arbitrary :: Gen Octet + oct2 <- arbitrary :: Gen Octet + oct3 <- arbitrary :: Gen Octet + oct4 <- arbitrary :: Gen Octet + return (IPv4Address oct1 oct2 oct3 oct4) instance Maskable IPv4Address where - apply_mask _ Maskbits.None _ = IPv4Address.None - 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), + + 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 == 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), + | 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 == Eight = addr { octet2 = (apply_mask oct2 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 == Seven = addr { octet1 = (apply_mask oct1 Seven bit), - octet2 = (apply_mask oct2 Zero bit), + | mask == Thirteen = addr { octet2 = (apply_mask oct2 Five 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), + | mask == Twelve = addr { octet2 = (apply_mask oct2 Four 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), + | mask == Eleven = addr { octet2 = (apply_mask oct2 Three 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)} - | otherwise = IPv4Address.None - where - oct1 = (octet1 addr) - oct2 = (octet2 addr) - oct3 = (octet3 addr) - oct4 = (octet4 addr) - + | 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) --- We don't export our constructor so this function is the only --- way to construct an address from octets. As a result, we can --- return IPv4Address.None in response to being passed one of more --- Octet.None octets. -ipv4address_from_octets :: Octet -> Octet -> Octet -> Octet -> IPv4Address -ipv4address_from_octets oct1 oct2 oct3 oct4 - | or [oct1 == Octet.None, - oct2 == Octet.None, - oct3 == Octet.None, - oct4 == Octet.None] = IPv4Address.None - | otherwise = IPv4Address oct1 oct2 oct3 oct4 - --- The minimum possible IPv4 address, 0.0.0.0. +-- | The minimum possible IPv4 address, 0.0.0.0. min_address :: IPv4Address -min_address = IPv4Address min_octet min_octet min_octet min_octet +min_address = + IPv4Address min_octet min_octet min_octet min_octet --- The maximum possible IPv4 address, 255.255.255.255. +-- | The maximum possible IPv4 address, 255.255.255.255. max_address :: IPv4Address -max_address = IPv4Address max_octet max_octet max_octet max_octet +max_address = + IPv4Address max_octet max_octet max_octet max_octet --- Given two addresses, find the number of the most significant bit --- where they differ. If the addresses are the same, return --- Maskbits.Zero. +-- | Given two addresses, find the number of the most significant bit +-- where they differ. If the addresses are the same, return +-- Maskbits.Zero. most_sig_bit_different :: IPv4Address -> IPv4Address -> Maskbits most_sig_bit_different addr1 addr2 | addr1 == addr2 = Maskbits.Zero @@ -281,24 +265,38 @@ most_sig_bit_different addr1 addr2 -- HUnit Tests mk_testaddr :: Int -> Int -> Int -> Int -> IPv4Address mk_testaddr a b c d = - IPv4Address oct1 oct2 oct3 oct4 - where - oct1 = octet_from_int a - oct2 = octet_from_int b - oct3 = octet_from_int c - oct4 = octet_from_int d + IPv4Address oct1 oct2 oct3 oct4 + where + oct1 = fromJust $ octet_from_int a + oct2 = fromJust $ octet_from_int b + oct3 = fromJust $ octet_from_int c + oct4 = fromJust $ octet_from_int d 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" TwentyFour (most_sig_bit_different (mk_testaddr 10 1 1 0) (mk_testaddr 10 1 0 0)) + TestCase $ assertEqual "10.1.1.0 and 10.1.0.0 differ in bit 24" + TwentyFour + bit + where + 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" TwentyThree (most_sig_bit_different (mk_testaddr 10 1 2 0) (mk_testaddr 10 1 1 0)) + TestCase $ assertEqual "10.1.2.0 and 10.1.1.0 differ in bit 23" + TwentyThree + bit + where + 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 ] +ipv4address_tests = + [ test_most_sig_bit_different1, + test_most_sig_bit_different2 ] diff --git a/src/Main.hs b/src/Main.hs index 6fa7da9..b2fc64b 100644 --- a/src/Main.hs +++ b/src/Main.hs @@ -1,4 +1,5 @@ import Data.List ((\\), intercalate, intersperse) +import Data.Maybe (catMaybes, isNothing) import System.Exit (ExitCode(..), exitWith) import System.IO (stderr, hPutStrLn) @@ -114,35 +115,38 @@ main = do input <- inputfunc let cidr_strings = lines input - let cidrs = map Cidr.cidr_from_string cidr_strings + let cidrs = map cidr_from_string cidr_strings - if (any (== Cidr.None) cidrs) + if (any isNothing cidrs) then do putStrLn "Error: not valid CIDR notation." exitWith (ExitFailure exit_invalid_cidr) else do -- Nothing + -- Filter out only the valid ones. + let valid_cidrs = catMaybes cidrs + -- Get the mode of operation. mode <- CommandLine.parse_mode case mode of Regex -> do - let regexes = map cidr_to_regex cidrs - putStrLn $ alternate regexes + let regexes = map cidr_to_regex valid_cidrs + putStrLn $ alternate regexes Reduce -> do - _ <- mapM (putStrLn . show) (combine_all cidrs) - return () + _ <- mapM (putStrLn . show) (combine_all valid_cidrs) + return () Dupe -> do - _ <- mapM (putStrLn . show) dupes - return () - where - dupes = cidrs \\ (combine_all cidrs) + _ <- mapM (putStrLn . show) dupes + return () + where + dupes = valid_cidrs \\ (combine_all valid_cidrs) Diff -> do - _ <- mapM putStrLn deletions - _ <- mapM putStrLn additions - return () - where - dupes = cidrs \\ (combine_all cidrs) - deletions = map (\s -> "-" ++ (show s)) dupes - newcidrs = (combine_all cidrs) \\ cidrs - additions = map (\s -> "+" ++ (show s)) newcidrs + _ <- mapM putStrLn deletions + _ <- mapM putStrLn additions + return () + where + dupes = valid_cidrs \\ (combine_all valid_cidrs) + deletions = map (\s -> "-" ++ (show s)) dupes + newcidrs = (combine_all valid_cidrs) \\ valid_cidrs + additions = map (\s -> "+" ++ (show s)) newcidrs diff --git a/src/Maskable.hs b/src/Maskable.hs index 9e72b8e..d05ff6f 100644 --- a/src/Maskable.hs +++ b/src/Maskable.hs @@ -3,19 +3,20 @@ module Maskable where import Bit import Maskbits --- Any string of bits should be maskable by some number of netmask --- bits. The convention of the Maskable typeclass follows CIDR --- notation, where the number of mask bits (the number after the --- slash) denotes how many bits are reserved for the network. +-- | Any string of bits should be maskable by some number of netmask +-- bits. The convention of the Maskable typeclass follows CIDR +-- notation, where the number of mask bits (the number after the +-- slash) denotes how many bits are reserved for the network. -- --- So, a mask of 32 applied to an address of 127.0.0.1 will again --- return 127.0.0.1. Likewise, 31 mask bits applied to 127.0.0.1 --- should return 127.0.0.0, since 127.0.0.1/31 matches both 127.0.0.0 --- and 127.0.0.1. In this case, the final '0' or '1' is the host --- part of the address. The '127.0.0' is thus the network part. +-- So, a mask of 32 applied to an address of 127.0.0.1 will again +-- return 127.0.0.1. Likewise, 31 mask bits applied to 127.0.0.1 +-- should return 127.0.0.0, since 127.0.0.1/31 matches both +-- 127.0.0.0 and 127.0.0.1. In this case, the final '0' or '1' is +-- the host part of the address. The '127.0.0' is thus the network +-- part. +-- +-- The Bit argument allows us to specify whether the host bits +-- should be replaced with either Zero or One. -- --- The Bit argument allows us to specify whether the host bits --- should be replaced with either Zero or One. class Maskable a where apply_mask :: a -> Maskbits -> Bit -> a - diff --git a/src/Maskbits.hs b/src/Maskbits.hs index 06314e3..d7064d8 100644 --- a/src/Maskbits.hs +++ b/src/Maskbits.hs @@ -7,167 +7,165 @@ module Maskbits import Test.QuickCheck -- A type representing the number of bits in a CIDR netmask. -data Maskbits = None - | Zero - | One - | Two - | Three - | Four - | Five - | Six - | Seven - | Eight - | Nine - | Ten - | Eleven - | Twelve - | Thirteen - | Fourteen - | Fifteen - | Sixteen - | Seventeen - | Eighteen - | Nineteen - | Twenty - | TwentyOne - | TwentyTwo - | TwentyThree - | TwentyFour - | TwentyFive - | TwentySix - | TwentySeven - | TwentyEight - | TwentyNine - | Thirty - | ThirtyOne - | ThirtyTwo - deriving (Eq, Ord) +data Maskbits = + Zero + | One + | Two + | Three + | Four + | Five + | Six + | Seven + | Eight + | Nine + | Ten + | Eleven + | Twelve + | Thirteen + | Fourteen + | Fifteen + | Sixteen + | Seventeen + | Eighteen + | Nineteen + | Twenty + | TwentyOne + | TwentyTwo + | TwentyThree + | TwentyFour + | TwentyFive + | TwentySix + | TwentySeven + | TwentyEight + | TwentyNine + | Thirty + | ThirtyOne + | ThirtyTwo + deriving (Eq, Ord) instance Show Maskbits where - show None = "None" - show Zero = "0" - show One = "1" - show Two = "2" - show Three = "3" - show Four = "4" - show Five = "5" - show Six = "6" - show Seven = "7" - show Eight = "8" - show Nine = "9" - show Ten = "10" - show Eleven = "11" - show Twelve = "12" - show Thirteen = "13" - show Fourteen = "14" - show Fifteen = "15" - show Sixteen = "16" - show Seventeen = "17" - show Eighteen = "18" - show Nineteen = "19" - show Twenty = "20" - show TwentyOne = "21" - show TwentyTwo = "22" - show TwentyThree = "23" - show TwentyFour = "24" - show TwentyFive = "25" - show TwentySix = "26" - show TwentySeven = "27" - show TwentyEight = "28" - show TwentyNine = "29" - show Thirty = "30" - show ThirtyOne = "31" - show ThirtyTwo = "32" + show Zero = "0" + show One = "1" + show Two = "2" + show Three = "3" + show Four = "4" + show Five = "5" + show Six = "6" + show Seven = "7" + show Eight = "8" + show Nine = "9" + show Ten = "10" + show Eleven = "11" + show Twelve = "12" + show Thirteen = "13" + show Fourteen = "14" + show Fifteen = "15" + show Sixteen = "16" + show Seventeen = "17" + show Eighteen = "18" + show Nineteen = "19" + show Twenty = "20" + show TwentyOne = "21" + show TwentyTwo = "22" + show TwentyThree = "23" + show TwentyFour = "24" + show TwentyFive = "25" + show TwentySix = "26" + show TwentySeven = "27" + show TwentyEight = "28" + show TwentyNine = "29" + show Thirty = "30" + show ThirtyOne = "31" + show ThirtyTwo = "32" instance Arbitrary Maskbits where - arbitrary = elements [ Zero, - One, - Two, - Three, - Four, - Five, - Six, - Seven, - Eight, - Nine, - Ten, - Eleven, - Twelve, - Thirteen, - Fourteen, - Fifteen, - Sixteen, - Seventeen, - Eighteen, - Nineteen, - Twenty, - TwentyOne, - TwentyTwo, - TwentyThree, - TwentyFour, - TwentyFive, - TwentySix, - TwentySeven, - TwentyEight, - TwentyNine, - Thirty, - ThirtyOne, - ThirtyTwo ] + arbitrary = + elements [ Zero, + One, + Two, + Three, + Four, + Five, + Six, + Seven, + Eight, + Nine, + Ten, + Eleven, + Twelve, + Thirteen, + Fourteen, + Fifteen, + Sixteen, + Seventeen, + Eighteen, + Nineteen, + Twenty, + TwentyOne, + TwentyTwo, + TwentyThree, + TwentyFour, + TwentyFive, + TwentySix, + TwentySeven, + TwentyEight, + TwentyNine, + Thirty, + ThirtyOne, + ThirtyTwo ] --- There are only 32 bits in an IPv4 address, so there --- can't be more bits than that in the mask. -maskbits_from_int :: Int -> Maskbits -maskbits_from_int 0 = Zero -maskbits_from_int 1 = One -maskbits_from_int 2 = Two -maskbits_from_int 3 = Three -maskbits_from_int 4 = Four -maskbits_from_int 5 = Five -maskbits_from_int 6 = Six -maskbits_from_int 7 = Seven -maskbits_from_int 8 = Eight -maskbits_from_int 9 = Nine -maskbits_from_int 10 = Ten -maskbits_from_int 11 = Eleven -maskbits_from_int 12 = Twelve -maskbits_from_int 13 = Thirteen -maskbits_from_int 14 = Fourteen -maskbits_from_int 15 = Fifteen -maskbits_from_int 16 = Sixteen -maskbits_from_int 17 = Seventeen -maskbits_from_int 18 = Eighteen -maskbits_from_int 19 = Nineteen -maskbits_from_int 20 = Twenty -maskbits_from_int 21 = TwentyOne -maskbits_from_int 22 = TwentyTwo -maskbits_from_int 23 = TwentyThree -maskbits_from_int 24 = TwentyFour -maskbits_from_int 25 = TwentyFive -maskbits_from_int 26 = TwentySix -maskbits_from_int 27 = TwentySeven -maskbits_from_int 28 = TwentyEight -maskbits_from_int 29 = TwentyNine -maskbits_from_int 30 = Thirty -maskbits_from_int 31 = ThirtyOne -maskbits_from_int 32 = ThirtyTwo -maskbits_from_int _ = None +-- | There are only 32 bits in an IPv4 address, so there +-- can't be more bits than that in the mask. +maskbits_from_int :: Int -> Maybe Maskbits +maskbits_from_int 0 = Just Zero +maskbits_from_int 1 = Just One +maskbits_from_int 2 = Just Two +maskbits_from_int 3 = Just Three +maskbits_from_int 4 = Just Four +maskbits_from_int 5 = Just Five +maskbits_from_int 6 = Just Six +maskbits_from_int 7 = Just Seven +maskbits_from_int 8 = Just Eight +maskbits_from_int 9 = Just Nine +maskbits_from_int 10 = Just Ten +maskbits_from_int 11 = Just Eleven +maskbits_from_int 12 = Just Twelve +maskbits_from_int 13 = Just Thirteen +maskbits_from_int 14 = Just Fourteen +maskbits_from_int 15 = Just Fifteen +maskbits_from_int 16 = Just Sixteen +maskbits_from_int 17 = Just Seventeen +maskbits_from_int 18 = Just Eighteen +maskbits_from_int 19 = Just Nineteen +maskbits_from_int 20 = Just Twenty +maskbits_from_int 21 = Just TwentyOne +maskbits_from_int 22 = Just TwentyTwo +maskbits_from_int 23 = Just TwentyThree +maskbits_from_int 24 = Just TwentyFour +maskbits_from_int 25 = Just TwentyFive +maskbits_from_int 26 = Just TwentySix +maskbits_from_int 27 = Just TwentySeven +maskbits_from_int 28 = Just TwentyEight +maskbits_from_int 29 = Just TwentyNine +maskbits_from_int 30 = Just Thirty +maskbits_from_int 31 = Just ThirtyOne +maskbits_from_int 32 = Just ThirtyTwo +maskbits_from_int _ = Nothing - -maskbits_from_string :: String -> Maskbits +maskbits_from_string :: String -> Maybe Maskbits maskbits_from_string s = - case (reads s :: [(Int, String)]) of - [] -> None - x:_ -> maskbits_from_int (fst x) + case (reads s :: [(Int, String)]) of + [] -> Nothing + x:_ -> maskbits_from_int (fst x) decrement :: Maskbits -> Maskbits -decrement None = None -decrement Zero = None +decrement Zero = Zero decrement One = Zero decrement Two = One decrement Three = Two diff --git a/src/Octet.hs b/src/Octet.hs index 7faf1d7..2e372fd 100644 --- a/src/Octet.hs +++ b/src/Octet.hs @@ -1,5 +1,7 @@ -module Octet where +module Octet +where +import Data.Maybe (fromJust) import Test.HUnit import Test.QuickCheck @@ -7,128 +9,156 @@ import Bit as B import Maskable import Maskbits --- An Octet consists of eight bits. For our purposes, the most --- significant bit will come "first." That is, b1 is in the 2^7 --- place while b8 is in the 2^0 place. -data Octet = None | Octet { b1 :: Bit, - b2 :: Bit, - b3 :: Bit, - b4 :: Bit, - b5 :: Bit, - b6 :: Bit, - b7 :: Bit, - b8 :: Bit } - deriving (Eq) +-- | An Octet consists of eight bits. For our purposes, the most +-- significant bit will come "first." That is, b1 is in the 2^7 +-- place while b8 is in the 2^0 place. +data Octet = + Octet { b1 :: Bit, + b2 :: Bit, + b3 :: Bit, + b4 :: Bit, + b5 :: Bit, + b6 :: Bit, + b7 :: Bit, + b8 :: Bit } + deriving (Eq) instance Show Octet where - show Octet.None = "None" - show oct = show (octet_to_int oct) + show oct = show (octet_to_int oct) instance Arbitrary Octet where - arbitrary = do - a1 <- arbitrary :: Gen Bit - a2 <- arbitrary :: Gen Bit - a3 <- arbitrary :: Gen Bit - a4 <- arbitrary :: Gen Bit - a5 <- arbitrary :: Gen Bit - a6 <- arbitrary :: Gen Bit - a7 <- arbitrary :: Gen Bit - a8 <- arbitrary :: Gen Bit - return (Octet a1 a2 a3 a4 a5 a6 a7 a8) + arbitrary = do + a1 <- arbitrary :: Gen Bit + a2 <- arbitrary :: Gen Bit + a3 <- arbitrary :: Gen Bit + a4 <- arbitrary :: Gen Bit + a5 <- arbitrary :: Gen Bit + a6 <- arbitrary :: Gen Bit + a7 <- arbitrary :: Gen Bit + a8 <- arbitrary :: Gen Bit + return (Octet a1 a2 a3 a4 a5 a6 a7 a8) instance Maskable Octet where - apply_mask _ Maskbits.None _ = Octet.None - apply_mask Octet.None _ _ = Octet.None - apply_mask oct mask bit - | mask == Eight = oct - | mask == Seven = oct { b8 = bit } - | mask == Six = oct { b8 = bit, b7 = bit } - | mask == Five = oct { b8 = bit, b7 = bit, b6 = bit } - | mask == Four = oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit } - | mask == Three = oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit } - | mask == Two = oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit, b3 = bit } - | mask == Maskbits.One = oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit, b3 = bit, b2 = bit } - | mask == Maskbits.Zero = oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit, b3 = bit, b2 = bit, b1 = bit } - | otherwise = Octet.None - - --- Convert each bit to its integer value, and multiply by the --- appropriate power of two. Sum them up, and we should get an integer --- between 0 and 255. + apply_mask oct Eight _ = oct + + apply_mask oct Seven bit = + oct { b8 = bit } + + apply_mask oct Six bit = + oct { b8 = bit, b7 = bit } + + apply_mask oct Five bit = + oct { b8 = bit, b7 = bit, b6 = bit } + + apply_mask oct Four bit = + oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit } + + apply_mask oct Three bit = + oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit } + + apply_mask oct Two bit = + oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, b4 = bit, b3 = bit } + + apply_mask oct Maskbits.One bit = + oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, + b4 = bit, b3 = bit, b2 = bit } + + apply_mask oct Maskbits.Zero bit = + oct { b8 = bit, b7 = bit, b6 = bit, b5 = bit, + b4 = bit, b3 = bit, b2 = bit, b1 = bit } + + -- The Maskbits must be in [Eight..ThirtyTwo]. + apply_mask oct _ _ = oct + + +-- | Convert each bit to its integer value, and multiply by the +-- appropriate power of two. Sum them up, and we should get an integer +-- between 0 and 255. octet_to_int :: Octet -> Int octet_to_int x = - 128 * (bit_to_int (b1 x)) + - 64 * (bit_to_int (b2 x)) + - 32 * (bit_to_int (b3 x)) + - 16 * (bit_to_int (b4 x)) + - 8 * (bit_to_int (b5 x)) + - 4 * (bit_to_int (b6 x)) + - 2 * (bit_to_int (b7 x)) + - 1 * (bit_to_int (b8 x)) + 128 * (bit_to_int (b1 x)) + + 64 * (bit_to_int (b2 x)) + + 32 * (bit_to_int (b3 x)) + + 16 * (bit_to_int (b4 x)) + + 8 * (bit_to_int (b5 x)) + + 4 * (bit_to_int (b6 x)) + + 2 * (bit_to_int (b7 x)) + + 1 * (bit_to_int (b8 x)) -octet_from_int :: Int -> Octet +octet_from_int :: Int -> Maybe Octet octet_from_int x - | (x < 0) || (x > 255) = Octet.None - | otherwise = (Octet a1 a2 a3 a4 a5 a6 a7 a8) - where - a1 = if (x >= 128) then B.One else B.Zero - a2 = if ((x `mod` 128) >= 64) then B.One else B.Zero - a3 = if ((x `mod` 64) >= 32) then B.One else B.Zero - a4 = if ((x `mod` 32) >= 16) then B.One else B.Zero - a5 = if ((x `mod` 16) >= 8) then B.One else B.Zero - a6 = if ((x `mod` 8) >= 4) then B.One else B.Zero - a7 = if ((x `mod` 4) >= 2) then B.One else B.Zero - a8 = if ((x `mod` 2) == 1) then B.One else B.Zero - - -octet_from_string :: String -> Octet + | (x < 0) || (x > 255) = Nothing + | otherwise = Just (Octet a1 a2 a3 a4 a5 a6 a7 a8) + where + a1 = if (x >= 128) then B.One else B.Zero + a2 = if ((x `mod` 128) >= 64) then B.One else B.Zero + a3 = if ((x `mod` 64) >= 32) then B.One else B.Zero + a4 = if ((x `mod` 32) >= 16) then B.One else B.Zero + a5 = if ((x `mod` 16) >= 8) then B.One else B.Zero + a6 = if ((x `mod` 8) >= 4) then B.One else B.Zero + a7 = if ((x `mod` 4) >= 2) then B.One else B.Zero + a8 = if ((x `mod` 2) == 1) then B.One else B.Zero + + +octet_from_string :: String -> Maybe Octet octet_from_string s = - case (reads s :: [(Int, String)]) of - [] -> Octet.None - x:_ -> octet_from_int (fst x) + case (reads s :: [(Int, String)]) of + [] -> Nothing + x:_ -> octet_from_int (fst x) --- The octet with the least possible value. +-- | The octet with the least possible value. min_octet :: Octet -min_octet = Octet B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero +min_octet = + Octet B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero --- The octet with the greatest possible value. +-- | The octet with the greatest possible value. max_octet :: Octet -max_octet = Octet B.One B.One B.One B.One B.One B.One B.One B.One +max_octet = + Octet B.One B.One B.One B.One B.One B.One B.One B.One -- HUnit Tests test_octet_from_int1 :: Test test_octet_from_int1 = - TestCase $ assertEqual "octet_from_int 128 should parse as 10000000" oct1 (octet_from_int 128) - where - oct1 = Octet B.One B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero - + TestCase $ assertEqual "octet_from_int 128 should parse as 10000000" oct1 oct2 + where + oct1 = Octet B.One B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero B.Zero + oct2 = fromJust $ octet_from_int 128 test_octet_mask1 :: Test test_octet_mask1 = - TestCase $ assertEqual "The network bits of 255/4 should equal 240" oct2 (apply_mask oct1 Four B.Zero) - where - oct1 = octet_from_int 255 - oct2 = octet_from_int 240 + TestCase $ + assertEqual + "The network bits of 255/4 should equal 240" + oct2 + (apply_mask oct1 Four B.Zero) + where + oct1 = fromJust $ octet_from_int 255 + oct2 = fromJust $ octet_from_int 240 test_octet_mask2 :: Test test_octet_mask2 = - TestCase $ assertEqual "The network bits of 255/1 should equal 128" oct2 (apply_mask oct1 Maskbits.One B.Zero) - where - oct1 = octet_from_int 255 - oct2 = octet_from_int 128 + TestCase $ + assertEqual + "The network bits of 255/1 should equal 128" + oct2 + (apply_mask oct1 Maskbits.One B.Zero) + where + oct1 = fromJust $ octet_from_int 255 + oct2 = fromJust $ octet_from_int 128 octet_tests :: [Test] -octet_tests = [ test_octet_from_int1, - test_octet_mask1, - test_octet_mask2 ] +octet_tests = + [ test_octet_from_int1, + test_octet_mask1, + test_octet_mask2 ]