4 import Control.Concurrent.ParallelIO.Global ( stopGlobalPool )
5 import Control.Monad (when)
6 import qualified Data.ByteString.Char8 as BS (intercalate, pack, unpack)
7 import Data.List ((\\), intercalate)
8 import Data.Maybe (catMaybes, isNothing)
9 import Data.String.Utils (splitWs)
10 import System.Exit (ExitCode(..), exitWith)
11 import System.IO (stderr, hPutStrLn)
12 import Text.Read (readMaybe)
26 import CommandLine (Args(..), get_args)
27 import DNS (Domain, PTRResult, lookup_ptrs)
28 import ExitCodes ( exit_invalid_cidr )
32 -- | A regular expression that matches a non-address character.
33 non_addr_char :: String
34 non_addr_char = "[^\\.0-9]"
37 -- | Add non_addr_chars on either side of the given String. This
38 -- prevents (for example) the regex '127.0.0.1' from matching
40 add_barriers :: String -> String
41 add_barriers x = non_addr_char ++ x ++ non_addr_char
44 -- | The magic happens here. We take a CIDR String as an argument, and
45 -- return the equivalent regular expression. We do this as follows:
47 -- 1. Compute the minimum possible value of each octet.
48 -- 2. Compute the maximum possible value of each octet.
49 -- 3. Generate a regex matching every value between those min and
51 -- 4. Join the regexes from step 3 with regexes matching periods.
52 -- 5. Stick an address boundary on either side of the result if
53 -- use_barriers is True.
55 cidr_to_regex :: Bool -> Cidr.Cidr -> String
56 cidr_to_regex use_barriers cidr =
57 let f = if use_barriers then add_barriers else id in
58 f (intercalate "\\." [range1, range2, range3, range4])
60 range1 = numeric_range min1 max1
61 range2 = numeric_range min2 max2
62 range3 = numeric_range min3 max3
63 range4 = numeric_range min4 max4
64 min1 = fromEnum (min_octet1 cidr)
65 min2 = fromEnum (min_octet2 cidr)
66 min3 = fromEnum (min_octet3 cidr)
67 min4 = fromEnum (min_octet4 cidr)
68 max1 = fromEnum (max_octet1 cidr)
69 max2 = fromEnum (max_octet2 cidr)
70 max3 = fromEnum (max_octet3 cidr)
71 max4 = fromEnum (max_octet4 cidr)
75 -- | Take a list of Strings, and return a regular expression matching
77 alternate :: [String] -> String
78 alternate terms = "(" ++ (intercalate "|" terms) ++ ")"
81 -- | Take two Ints as parameters, and return a regex matching any
82 -- integer between them (inclusive).
84 -- IMPORTANT: we match from max to min so that if e.g. the last
85 -- octet is '255', we want '255' to match before '2' in the regex
86 -- (255|254|...|3|2|1) which does not happen if we use
87 -- (1|2|3|...|254|255).
89 numeric_range :: Int -> Int -> String
91 alternate (map show $ reverse [lower..upper])
104 let cidr_strings = splitWs input
105 let cidrs = map readMaybe cidr_strings
107 when (any isNothing cidrs) $ do
108 hPutStrLn stderr "ERROR: not valid CIDR notation:"
110 -- Output the bad lines, safely.
111 let pairs = zip cidr_strings cidrs
112 let print_pair (x, Nothing) = hPutStrLn stderr (" * " ++ x)
113 print_pair (_, _) = return ()
115 mapM_ print_pair pairs
116 exitWith (ExitFailure exit_invalid_cidr)
118 -- Filter out only the valid ones.
119 let valid_cidrs = catMaybes cidrs
123 let cidrs' = combine_all valid_cidrs
124 let regexes = map (cidr_to_regex (barriers args)) cidrs'
125 putStrLn $ alternate regexes
127 mapM_ print (combine_all valid_cidrs)
131 dupes = valid_cidrs \\ (combine_all valid_cidrs)
133 mapM_ putStrLn deletions
134 mapM_ putStrLn additions
136 dupes = valid_cidrs \\ (combine_all valid_cidrs)
137 deletions = map (\s -> '-' : (show s)) dupes
138 newcidrs = (combine_all valid_cidrs) \\ valid_cidrs
139 additions = map (\s -> '+' : (show s)) newcidrs
141 let combined_cidrs = combine_all valid_cidrs
142 let addrs = concatMap enumerate combined_cidrs
145 let combined_cidrs = combine_all valid_cidrs
146 let addrs = concatMap enumerate combined_cidrs
147 let addr_bytestrings = map (BS.pack . show) addrs
148 ptrs <- lookup_ptrs addr_bytestrings
149 let pairs = zip addr_bytestrings ptrs
150 mapM_ (putStrLn . show_pair) pairs
155 show_pair :: (Domain, PTRResult) -> String
157 (BS.unpack s) ++ ": " ++ results
162 Left err -> "ERROR (" ++ (show err) ++ ")"
163 Right ds -> BS.unpack $ BS.intercalate space ds