X-Git-Url: http://gitweb.michael.orlitzky.com/?p=haeredes.git;a=blobdiff_plain;f=src%2FMain.hs;h=4e0da6b6dc0296e730025f5295219eeaae254fe1;hp=142ace670cf62d4a83796c431185d5af2eeb891f;hb=f9610a6d357f2ed79f2f18baa477244970f8b40f;hpb=825753e2731b8491d93d9f2d66b457fe31b1c763 diff --git a/src/Main.hs b/src/Main.hs index 142ace6..4e0da6b 100644 --- a/src/Main.hs +++ b/src/Main.hs @@ -1,68 +1,115 @@ module Main where -import qualified Data.ByteString.Char8 as BS (pack) +import Control.Concurrent.ParallelIO.Global ( + parallel, + stopGlobalPool ) +import Control.Monad (unless) +import qualified Data.ByteString.Char8 as BS ( + getContents, + pack, + words ) import Data.List ((\\)) -import Data.String.Utils (join, splitWs) - +import Data.String.Utils (join) import Network.DNS ( Domain, FileOrNumericHost(RCHostName), - ResolvConf(resolvInfo), + ResolvConf(resolvInfo, resolvTimeout), defaultResolvConf, - lookupNS, makeResolvSeed, - withResolver - ) + withResolver ) +import System.Exit (ExitCode(..), exitWith) +import System.IO (hPutStrLn, stderr) + -import System.IO (hGetContents, stdin) +import CommandLine (Args(..), get_args) +import DNS ( + LookupResult, + lookupMX', + lookupNS', + normalize, + normalize_case, + resolve_address ) +import ExitCodes (exit_bad_server) +import Timeout (Timeout(..)) -import CommandLine (Args(..), Delegates(..), get_args) -report :: (Domain, Maybe [Domain]) -> IO () +-- | Report results for this LookupResult. If there's a Nothing in the +-- second component, there were no query results, so we report that +-- the domain was not delegated. If there were some results and +-- there are leftovers (after "cleaning"), we report those as well. +report :: LookupResult -> IO () report (d, Nothing) = putStrLn $ "Domain " ++ (show d) ++ " not delegated." report (d, Just leftovers) = - if null leftovers - then return () - else putStrLn $ "Domain " ++ - (show d) ++ - " delegates somewhere else: " ++ - (join " " (map show leftovers)) - -clean :: Delegates -> (Domain, Maybe [Domain]) -> (Domain, Maybe [Domain]) + unless (null leftovers) $ + putStrLn $ "Domain " ++ + (show d) ++ + " delegates somewhere else: " ++ + (join " " (map show leftovers)) + + +-- | "Clean" a lookup result by subtracting out the list of delegates. +-- There shouldn't be anything left over. If there were no lookup +-- results, we leave the Nothing in place so that 'report' can +-- pattern match on it. +clean :: [Domain] -- ^ List of delegates, @ds@ + -> LookupResult + -> LookupResult clean _ p@(_, Nothing) = p -clean (Delegates ds') (d, Just targets) = - (d, Just $ targets \\ ds) - where - ds = map BS.pack ds' +clean delgts (d, Just targets) = + (d, Just $ targets \\ delgts) + + main :: IO () main = do cfg <- get_args - print cfg - input <- hGetContents stdin + + -- This reads stdin. + input <- BS.getContents -- Split the input on any whitespace characters. - let domains' = splitWs input + let raw_domains = BS.words input + + -- Convert these to ByteStrings. + let raw_delegates = map BS.pack (delegates cfg) + + let normalize_function = + if (no_append_root cfg) + then normalize_case + else normalize - -- Convert those Strings to ByteStrings - let domains = map BS.pack domains' + -- Normalize the given names and delegates + let nrml_domains = map normalize_function raw_domains + let nrml_delegates = map normalize_function raw_delegates - let rc = case (server cfg) of - Nothing -> defaultResolvConf - Just s -> defaultResolvConf { resolvInfo = RCHostName s } + rc' <- case (server cfg) of + Nothing -> return defaultResolvConf + Just s -> do + s' <- resolve_address s + case s' of + Nothing -> do + hPutStrLn stderr ("Bad DNS server or lookup error: " ++ s) + exitWith (ExitFailure exit_bad_server) + Just s'' -> + return $ defaultResolvConf { resolvInfo = + RCHostName (show s'') } + -- Set the timeout from the command line. The resolvTimeout field is + -- in microseconds, so we multiply by one million. + let rc = rc' { resolvTimeout = 1000 * 1000 * (seconds $ timeout cfg) } rs <- makeResolvSeed rc - withResolver rs $ \resolver -> do - -- This function keeps the domain matches with its NS records. - let lookupNS' = \d -> (lookupNS resolver d) >>= (return . ((,) d)) - domains_ns <- mapM lookupNS' domains - let cdns = map (clean (delegates cfg)) domains_ns - - case cfg of - (NS _ _) -> - -- We're only checking NS records, so report what we found. - mapM_ report cdns - (MX _ _) -> - print "Hello, world." + + let lookup_function = case cfg of + NS{} -> lookupNS' + MX{} -> lookupMX' + + _ <- withResolver rs $ \resolver -> do + -- Bad stuff happens if we try to run these lookups in parallel + -- instead of the reports. + records <- mapM (lookup_function resolver) nrml_domains + let cleaned_records = map (clean nrml_delegates) records + parallel (map report cleaned_records) + + stopGlobalPool