1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE ScopedTypeVariables #-}
--------------------------------------------------------------------------------
-- | Get a certificate from Let's Encrypt using the ACME protocol.
--
-- https://github.com/ietf-wg-acme/acme/blob/master/draft-ietf-acme-acme.md
module Network.ACME where
import Control.Lens hiding (each, (.=))
import Control.Monad
import Control.Monad.RWS.Strict
import Data.Aeson (Value)
import Data.Aeson.Lens hiding (key)
import qualified Data.Aeson.Lens as JSON
import Data.ByteString (ByteString)
import qualified Data.ByteString.Char8 as BC
import qualified Data.ByteString.Lazy as LB
import qualified Data.ByteString.Lazy.Char8 as LC
import Data.Coerce
import Data.String (fromString)
import qualified Data.Text as T
import Data.Text.Encoding (decodeUtf8, encodeUtf8)
import Data.Time.Clock.POSIX (getPOSIXTime)
import Network.ACME.Encoding
import Network.Wreq (Response, checkStatus, defaults,
responseBody, responseHeader,
responseStatus, statusCode,
statusMessage)
import qualified Network.Wreq as W
import qualified Network.Wreq.Session as WS
import OpenSSL.RSA
import System.Directory
import Text.Email.Validate
import Text.Domain.Validate hiding (validate)
import Network.URI
certify :: URI -> Keys -> Maybe EmailAddress -> URI -> [DomainName] -> WritableDir -> CSR -> IO (Either String LC.ByteString)
certify directoryUrl keys optEmail terms requestDomains optChallengeDir csrData =
runACME directoryUrl keys $ do
forM_ optEmail $ register terms >=> statusReport
let performChallenge (ChallengeRequest nextUri token thumbtoken) = do
liftIO $ BC.writeFile (coerce optChallengeDir </> BC.unpack token) thumbtoken
notifyChallenge nextUri thumbtoken >>= statusReport >>= ncErrorReport
challengeResultLinks <- forM requestDomains $ challengeRequest >=> statusReport >=> extractCR >=> performChallenge
pollResults challengeResultLinks >>=
either (return . Left . ("certificate receipt was not attempted because a challenge failed: " ++))
(const (retrieveCert csrData >>= statusReport <&> checkCertResponse))
pollResults :: [Response LC.ByteString] -> ACME (Either String ())
pollResults [] = return $ Right ()
pollResults (link:links) = do
-- TODO: use "Retry-After" header if present
let Just uri = link ^? responseBody . JSON.key "uri" . _String
r <- liftIO $ W.get (T.unpack uri)
let status = r ^. responseBody . JSON.key "status" . _String
case status of
"pending" -> pollResults $ links ++ [r]
"valid" -> pollResults links
"invalid" -> return . Left $ r ^. responseBody . JSON.key "error" . to extractAcmeError
_ -> return . Left $ "unexpected response from ACME server: " ++ show r
data ChallengeRequest = ChallengeRequest { crUri :: String, crToken :: ByteString, crThumbToken :: ByteString }
newtype CSR = CSR ByteString
newtype WritableDir = WritableDir String
ensureWritableDir :: FilePath -> String -> IO WritableDir
ensureWritableDir file name = do
(writable <$> getPermissions file) >>= flip unless (err name)
return $ WritableDir file
where err n = error $ "Error: " ++ n ++ " is not writable"
(</>) :: String -> String -> String
a </> b = a ++ "/" ++ b
infixr 5 </>
domainToString :: DomainName -> String
domainToString = T.unpack . decodeUtf8 . Text.Domain.Validate.toByteString
canProvision :: WritableDir -> DomainName -> IO Bool
canProvision challengeDir domain = do
randomish <- fromString . show <$> getPOSIXTime
let absFile = coerce challengeDir </> relFile
relFile = ".test." ++ show randomish
LC.writeFile absFile randomish
r <- W.get $ "http://" ++ domainToString domain </> ".well-known/acme-challenge" </> relFile
removeFile absFile
return $ r ^. responseBody == randomish
extractCR :: MonadReader Env m => Response LC.ByteString -> m ChallengeRequest
extractCR r = do
Keys _ pub <- asks getKeys
let httpChallenge :: (Value -> Const (Endo s) Value) -> Response LC.ByteString -> Const (Endo s) (Response LC.ByteString)
httpChallenge = responseBody .
JSON.key "challenges" .
to universe .
traverse .
(filtered . has $ ix "type" . only "http-01")
token = r ^?! httpChallenge . JSON.key "token" . _String . to encodeUtf8
nextU = r ^?! httpChallenge . JSON.key "uri" . _String . to T.unpack
thumb = thumbprint (JWK (rsaE pub) "RSA" (rsaN pub))
thumbtoken = toStrict (LB.fromChunks [token, ".", thumb])
return $ ChallengeRequest nextU token thumbtoken
ncErrorReport :: (Show body, AsValue body, MonadIO m) => Response body -> m (Response body)
ncErrorReport r = do
when (Just "pending" /= r ^? responseBody . JSON.key "status" . _String) $ liftIO $ do
putStrLn "Unexpected response to challenge-response request:"
print r
return r
extractAcmeError :: forall s. AsValue s => s -> String
extractAcmeError r = summary ++ " ---- " ++ details
where
(Just summary, Just details) = (k "type", k "detail")
k x = r ^? JSON.key x . _String . to T.unpack
checkCertResponse :: Response LC.ByteString -> Either String LC.ByteString
checkCertResponse r =
if isSuccess $ r ^. responseStatus . statusCode
then Right $ r ^. responseBody
else Left $ r ^. responseBody . to extractAcmeError
where
isSuccess n = n >= 200 && n <= 300
retrieveCert :: (MonadReader Env m, MonadState Nonce m, MonadIO m) => CSR -> m (Response LC.ByteString)
retrieveCert input = sendPayload _newCert (csr $ coerce input)
notifyChallenge :: (MonadReader Env m, MonadState Nonce m, MonadIO m) => String -> ByteString -> m (Response LC.ByteString)
notifyChallenge uri thumbtoken = sendPayload (const uri) (challenge thumbtoken)
data Env = Env { getDir :: Directory, getKeys :: Keys, getSession :: WS.Session }
type ACME = RWST Env () Nonce IO
runACME :: URI -> Keys -> ACME a -> IO a
runACME url keys f = WS.withSession $ \sess -> do
Just (dir, nonce) <- getDirectory sess (show url)
fst <$> evalRWST f (Env dir keys sess) nonce
data Directory = Directory {
_newCert :: String,
_newAuthz :: String,
_revokeCert :: String,
_newReg :: String
}
newtype Nonce = Nonce String
getDirectory :: WS.Session -> String -> IO (Maybe (Directory, Nonce))
getDirectory sess url = do
r <- WS.get sess url
let nonce = r ^? responseHeader "Replay-Nonce" . to (Nonce . T.unpack . decodeUtf8)
k x = r ^? responseBody . JSON.key x . _String . to T.unpack
return $ (,) <$> (Directory <$> k "new-cert" <*> k "new-authz" <*> k "revoke-cert" <*> k "new-reg") <*> nonce
register :: URI -> EmailAddress -> ACME (Response LC.ByteString)
register terms email = sendPayload _newReg (registration email (show terms))
challengeRequest :: (MonadIO m, MonadState Nonce m, MonadReader Env m) => DomainName -> m (Response LC.ByteString)
challengeRequest = sendPayload _newAuthz . authz . domainToString
statusLine :: Response body -> String
statusLine r = (r ^. responseStatus . statusCode . to show) ++ " " ++ r ^. responseStatus . statusMessage . to (T.unpack . decodeUtf8)
statusReport :: MonadIO m => Response body -> m (Response body)
statusReport r = do
liftIO $ putStrLn $ statusLine r
return r
sendPayload :: (MonadIO m, MonadState Nonce m, MonadReader Env m) => (Directory -> String) -> ByteString -> m (Response LC.ByteString)
sendPayload reqType payload = do
keys <- asks getKeys
dir <- asks getDir
nonce <- gets coerce
signed <- liftIO $ signPayload keys nonce payload
post (reqType dir) signed
post :: (MonadReader Env m, MonadState Nonce m, MonadIO m) => String -> LC.ByteString -> m (Response LC.ByteString)
post url payload = do
sess <- asks getSession
r <- liftIO $ WS.postWith noStatusCheck sess url payload
put $ r ^?! responseHeader "Replay-Nonce" . to (Nonce . T.unpack . decodeUtf8)
return r
where
noStatusCheck = defaults & checkStatus .~ Just nullChecker
nullChecker _ _ _ = Nothing
|
