git-annex/Assistant/Pairing/MakeRemote.hs
Joey Hess cd544e548b
filter out control characters in error messages
giveup changed to filter out control characters. (It is too low level to
make it use StringContainingQuotedPath.)

error still does not, but it should only be used for internal errors,
where the message is not attacker-controlled.

Changed a lot of existing error to giveup when it is not strictly an
internal error.

Of course, other exceptions can still be thrown, either by code in
git-annex, or a library, that include some attacker-controlled value.
This does not guard against those.

Sponsored-by: Noam Kremen on Patreon
2023-04-10 13:50:51 -04:00

98 lines
3.4 KiB
Haskell

{- git-annex assistant pairing remote creation
-
- Copyright 2012 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Assistant.Pairing.MakeRemote where
import Assistant.Common
import Assistant.Ssh
import Assistant.Pairing
import Assistant.Pairing.Network
import Assistant.MakeRemote
import Assistant.Sync
import Config.Cost
import Config
import qualified Types.Remote as Remote
import Network.Socket
import qualified Data.Text as T
{- Authorized keys are set up before pairing is complete, so that the other
- side can immediately begin syncing. -}
setupAuthorizedKeys :: PairMsg -> FilePath -> IO ()
setupAuthorizedKeys msg repodir = case validateSshPubKey $ remoteSshPubKey $ pairMsgData msg of
Left err -> giveup err
Right pubkey -> do
absdir <- fromRawFilePath <$> absPath (toRawFilePath repodir)
unlessM (liftIO $ addAuthorizedKeys True absdir pubkey) $
giveup "failed setting up ssh authorized keys"
{- When local pairing is complete, this is used to set up the remote for
- the host we paired with. -}
finishedLocalPairing :: PairMsg -> SshKeyPair -> Assistant ()
finishedLocalPairing msg keypair = do
sshdata <- liftIO $ installSshKeyPair keypair =<< pairMsgToSshData msg
{- Ensure that we know the ssh host key for the host we paired with.
- If we don't, ssh over to get it. -}
liftIO $ unlessM (knownHost $ sshHostName sshdata) $
void $ sshTranscript
[ sshOpt "StrictHostKeyChecking" "no"
, sshOpt "NumberOfPasswordPrompts" "0"
, "-n"
]
(genSshHost (sshHostName sshdata) (sshUserName sshdata))
("git-annex-shell -c configlist " ++ T.unpack (sshDirectory sshdata))
Nothing
r <- liftAnnex $ addRemote $ makeSshRemote sshdata
repo <- liftAnnex $ Remote.getRepo r
liftAnnex $ setRemoteCost repo semiExpensiveRemoteCost
syncRemote r
{- Mostly a straightforward conversion. Except:
- * Determine the best hostname to use to contact the host.
- * Strip leading ~/ from the directory name.
-}
pairMsgToSshData :: PairMsg -> IO SshData
pairMsgToSshData msg = do
let d = pairMsgData msg
hostname <- liftIO $ bestHostName msg
let dir = case remoteDirectory d of
('~':'/':v) -> v
v -> v
return SshData
{ sshHostName = T.pack hostname
, sshUserName = Just (T.pack $ remoteUserName d)
, sshDirectory = T.pack dir
, sshRepoName = genSshRepoName hostname dir
, sshPort = 22
, needsPubKey = True
, sshCapabilities = [GitAnnexShellCapable, GitCapable, RsyncCapable]
, sshRepoUrl = Nothing
}
{- Finds the best hostname to use for the host that sent the PairMsg.
-
- If remoteHostName is set, tries to use a .local address based on it.
- That's the most robust, if this system supports .local.
- Otherwise, looks up the hostname in the DNS for the remoteAddress,
- if any. May fall back to remoteAddress if there's no DNS. Ugh. -}
bestHostName :: PairMsg -> IO HostName
bestHostName msg = case remoteHostName $ pairMsgData msg of
Just h -> do
let localname = h ++ ".local"
addrs <- catchDefaultIO [] $
getAddrInfo Nothing (Just localname) Nothing
maybe fallback (const $ return localname) (headMaybe addrs)
Nothing -> fallback
where
fallback = do
let a = pairMsgAddr msg
let sockaddr = case a of
IPv4Addr addr -> SockAddrInet (fromInteger 0) addr
IPv6Addr addr -> SockAddrInet6 (fromInteger 0) 0 addr 0
fromMaybe (showAddr a)
<$> catchDefaultIO Nothing
(fst <$> getNameInfo [] True False sockaddr)