OpenSSL.Session

Functions for handling SSL connections. These functions use GHC specific calls to cooperative the with the scheduler so that blocking functions only actually block the Haskell thread, not a whole OS thread.

Contexts

data SSLContext

An SSL context. Contexts carry configuration such as a server's private key, root CA certiifcates etc. Contexts are stateful IO objects; they start empty and various options are set on them by the functions in this module. Note that an empty context will pretty much cause any operation to fail since it doesn't even have any ciphers enabled.

context :: IO SSLContext

Create a new SSL context.

contextAddOption :: SSLContext -> SSLOption -> IO ()

Add a protocol option to the context.

contextRemoveOption :: SSLContext -> SSLOption -> IO ()

Remove a protocol option from the context.

contextSetPrivateKey :: KeyPair k => SSLContext -> k -> IO ()

Install a private key into a context.

contextSetCertificate :: SSLContext -> X509 -> IO ()

Install a certificate (public key) into a context.

contextSetPrivateKeyFile :: SSLContext -> FilePath -> IO ()

Install a private key file in a context. The key is given as a path to the file which contains the key. The file is parsed first as PEM and, if that fails, as ASN1. If both fail, an exception is raised.

contextSetCertificateFile :: SSLContext -> FilePath -> IO ()

Install a certificate (public key) file in a context. The key is given as a path to the file which contains the key. The file is parsed first as PEM and, if that fails, as ASN1. If both fail, an exception is raised.

contextSetCertificateChainFile :: SSLContext -> FilePath -> IO ()

Install a certificate chain in a context. The certificates must be in PEM format and must be sorted starting with the subject's certificate (actual client or server certificate), followed by intermediate CA certificates if applicable, and ending at the highest level (root) CA.

contextSetCiphers :: SSLContext -> String -> IO ()

Set the ciphers to be used by the given context. The string argument is a list of ciphers, comma separated, as given at https://www.openssl.org/docs/manmaster/man1/openssl-ciphers.html.

Unrecognised ciphers are ignored. If no ciphers from the list are recognised, an exception is raised.

contextSetDefaultCiphers :: SSLContext -> IO ()

Set the ciphers to DEFAULT.

contextCheckPrivateKey :: SSLContext -> IO Bool

Return true iff the private key installed in the given context matches the certificate also installed.

data VerificationMode

See http://www.openssl.org/docs/ssl/SSL_CTX_set_verify.html

Constructors

VerifyNone

VerifyPeer

Fields

• vpFailIfNoPeerCert :: Bool

  is a certificate required

• vpClientOnce :: Bool

  only request once per connection

• vpCallback :: Maybe (Bool -> X509StoreCtx -> IO Bool)

  optional callback

contextSetVerificationMode :: SSLContext -> VerificationMode -> IO ()

contextSetDefaultVerifyPaths :: SSLContext -> IO ()

Specifies that the default locations from which CA certificates are loaded should be used. There is one default directory and one default file.

The default CA certificates directory is called "certs" in the default OpenSSL directory. Alternatively the SSL_CERT_DIR environment variable can be defined to override this location.

The default CA certificates file is called "cert.pem" in the default OpenSSL directory. Alternatively the SSL_CERT_FILE environment variable can be defined to override this location.

See https://www.openssl.org/docs/manmaster/man3/SSL_CTX_set_default_verify_paths.html for more information.

contextSetCAFile :: SSLContext -> FilePath -> IO ()

Set the location of a PEM encoded list of CA certificates to be used when verifying a server's certificate

contextSetCADirectory :: SSLContext -> FilePath -> IO ()

Set the path to a directory which contains the PEM encoded CA root certificates. This is an alternative to contextSetCAFile. See http://www.openssl.org/docs/ssl/SSL_CTX_load_verify_locations.html for details of the file naming scheme

contextGetCAStore :: SSLContext -> IO X509Store

Get a reference to, not a copy of, the X.509 certificate storage in the SSL context.

contextSetSessionIdContext :: SSLContext -> ByteString -> IO ()

Set context within which session can be reused (server side only).

If client certificates are used and the session id context is not set, attempts by the clients to reuse a session will make the handshake fail.

contextSetALPNProtos :: SSLContext -> [ByteString] -> IO ()

withContextSetKeylogCallback :: SSLContext -> (String -> IO ()) -> IO () -> IO ()

The key logging callback is called with a String "line". The line is a string containing the key material in the format used by NSS for its SSLKEYLOGFILE debugging output. To recreate that file, the key logging callback should log line, followed by a newline.

FIXME: Not re-entrant (ignores previous callback and resets it to nullFunPtr on exit)

SSL connections

data SSL

This is the type of an SSL connection

IO with SSL objects is non-blocking and many SSL functions return a error code which signifies that it needs to read or write more data. We handle these calls and call threadWaitRead and threadWaitWrite at the correct times. Thus multiple OS threads can be blocked inside IO in the same SSL object at a time, because they aren't really in the SSL object, they are waiting for the RTS to wake the Haskell thread.

data SSLResult a

This is the type of an SSL IO operation. Errors are handled by exceptions while everything else is one of these. Note that reading from an SSL socket can result in WantWrite and vice versa.

Constructors

SSLDone a

operation finished successfully

WantRead

needs more data from the network

WantWrite

needs more outgoing buffer space

Instances

Foldable SSLResult

Defined in OpenSSL.Session

Methods

fold :: Monoid m => SSLResult m -> m

foldMap :: Monoid m => (a -> m) -> SSLResult a -> m

foldMap' :: Monoid m => (a -> m) -> SSLResult a -> m

foldr :: (a -> b -> b) -> b -> SSLResult a -> b

foldr' :: (a -> b -> b) -> b -> SSLResult a -> b

foldl :: (b -> a -> b) -> b -> SSLResult a -> b

foldl' :: (b -> a -> b) -> b -> SSLResult a -> b

foldr1 :: (a -> a -> a) -> SSLResult a -> a

foldl1 :: (a -> a -> a) -> SSLResult a -> a

toList :: SSLResult a -> [a]

null :: SSLResult a -> Bool

length :: SSLResult a -> Int

elem :: Eq a => a -> SSLResult a -> Bool

maximum :: Ord a => SSLResult a -> a

minimum :: Ord a => SSLResult a -> a

sum :: Num a => SSLResult a -> a

product :: Num a => SSLResult a -> a

Traversable SSLResult

Defined in OpenSSL.Session

Methods

traverse :: Applicative f => (a -> f b) -> SSLResult a -> f (SSLResult b)

sequenceA :: Applicative f => SSLResult (f a) -> f (SSLResult a)

mapM :: Monad m => (a -> m b) -> SSLResult a -> m (SSLResult b)

sequence :: Monad m => SSLResult (m a) -> m (SSLResult a)

Functor SSLResult

Defined in OpenSSL.Session

Methods

fmap :: (a -> b) -> SSLResult a -> SSLResult b

(<$) :: a -> SSLResult b -> SSLResult a

Show a => Show (SSLResult a)

Defined in OpenSSL.Session

Methods

showsPrec :: Int -> SSLResult a -> ShowS

show :: SSLResult a -> String

showList :: [SSLResult a] -> ShowS

Eq a => Eq (SSLResult a)

Defined in OpenSSL.Session

Methods

(==) :: SSLResult a -> SSLResult a -> Bool

(/=) :: SSLResult a -> SSLResult a -> Bool

connection :: SSLContext -> Socket -> IO SSL

Wrap a Socket in an SSL connection. Reading and writing to the Socket after this will cause weird errors in the SSL code. The SSL object carries a handle to the Socket so you need not worry about the garbage collector closing the file descriptor out from under you.

fdConnection :: SSLContext -> Fd -> IO SSL

Wrap a socket Fd in an SSL connection.

addOption :: SSL -> SSLOption -> IO ()

Add a protocol option to the SSL connection.

removeOption :: SSL -> SSLOption -> IO ()

Remove a protocol option from the SSL connection.

setTlsextHostName :: SSL -> String -> IO ()

Set host name for Server Name Indication (SNI)

enableHostnameValidation :: SSL -> String -> IO ()

Enable hostname validation. Also see setTlsextHostName.

This uses the built-in mechanism introduced in 1.0.2/1.1.0, and will fail otherwise.

accept :: SSL -> IO ()

Perform an SSL server handshake

tryAccept :: SSL -> IO (SSLResult ())

Try to perform an SSL server handshake without blocking

connect :: SSL -> IO ()

Perform an SSL client handshake

tryConnect :: SSL -> IO (SSLResult ())

Try to perform an SSL client handshake without blocking

read :: SSL -> Int -> IO ByteString

Try to read the given number of bytes from an SSL connection. On EOF an empty ByteString is returned. If the connection dies without a graceful SSL shutdown, an exception is raised.

NOTE: The returned bytestring could be shorter than the size requested, see: https://www.openssl.org/docs/man3.0/man3/SSL_read.html

tryRead :: SSL -> Int -> IO (SSLResult ByteString)

Try to read the given number of bytes from an SSL connection without blocking.

NOTE: The returned bytestring could be shorter than the size requested, see: https://www.openssl.org/docs/man3.0/man3/SSL_read.html

readPtr :: SSL -> Ptr a -> Int -> IO Int

Read some data into a raw pointer buffer. Retrns the number of bytes read.

tryReadPtr :: SSL -> Ptr a -> Int -> IO (SSLResult Int)

Try to read some data into a raw pointer buffer, without blocking.

write :: SSL -> ByteString -> IO ()

Write a given ByteString to the SSL connection. Either all the data is written or an exception is raised because of an error.

tryWrite :: SSL -> ByteString -> IO (SSLResult ())

Try to write a given ByteString to the SSL connection without blocking.

writePtr :: SSL -> Ptr a -> Int -> IO ()

Send some data from a raw pointer buffer.

tryWritePtr :: SSL -> Ptr a -> Int -> IO (SSLResult ())

Send some data from a raw pointer buffer, without blocking.

lazyRead :: SSL -> IO ByteString

Lazily read all data until reaching EOF. If the connection dies without a graceful SSL shutdown, an exception is raised.

lazyWrite :: SSL -> ByteString -> IO ()

Write a lazy ByteString to the SSL connection. In contrast to write, there is a chance that the string is written partway and then an exception is raised for an error. The string doesn't necessarily have to be finite.

shutdown :: SSL -> ShutdownType -> IO ()

Cleanly shutdown an SSL connection. Note that SSL has a concept of a secure shutdown, which is distinct from just closing the TCP connection. This performs the former and should always be preferred.

This can either just send a shutdown, or can send and wait for the peer's shutdown message.

tryShutdown :: SSL -> ShutdownType -> IO (SSLResult ())

Try to cleanly shutdown an SSL connection without blocking.

data ShutdownType

Constructors

Bidirectional

wait for the peer to also shutdown

Unidirectional

only send our shutdown

Instances

Show ShutdownType

Defined in OpenSSL.Session

Methods

showsPrec :: Int -> ShutdownType -> ShowS

show :: ShutdownType -> String

showList :: [ShutdownType] -> ShowS

Eq ShutdownType

Defined in OpenSSL.Session

Methods

(==) :: ShutdownType -> ShutdownType -> Bool

(/=) :: ShutdownType -> ShutdownType -> Bool

getPeerCertificate :: SSL -> IO (Maybe X509)

After a successful connection, get the certificate of the other party. If this is a server connection, you probably won't get a certificate unless you asked for it with contextSetVerificationMode

getVerifyResult :: SSL -> IO Bool

Get the result of verifing the peer's certificate. This is mostly for clients to verify the certificate of the server that they have connected it. You must set a list of root CA certificates with contextSetCA... for this to make sense.

Note that this returns True iff the peer's certificate has a valid chain to a root CA. You also need to check that the certificate is correct (i.e. has the correct hostname in it) with getPeerCertificate.

sslSocket :: SSL -> Maybe Socket

Get the socket underlying an SSL connection

sslFd :: SSL -> Fd

Get the underlying socket Fd

Protocol Options

data SSLOption

The behaviour of the SSL library can be changed by setting several options. During a handshake, the option settings of the SSL object are used. When a new SSL object is created from a SSLContext, the current option setting is copied. Changes to SSLContext do not affect already created SSL objects.

Constructors

SSL_OP_MICROSOFT_SESS_ID_BUG

As of OpenSSL 1.0.0 this option has no effect.

SSL_OP_NETSCAPE_CHALLENGE_BUG

As of OpenSSL 1.0.0 this option has no effect.

SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG

As of OpenSSL 0.9.8q and 1.0.0c, this option has no effect.

SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG

As of OpenSSL 1.0.1h and 1.0.2, this option has no effect.

SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_SAFARI_ECDHE_ECDSA_BUG

Don't prefer ECDHE-ECDSA ciphers when the client appears to be Safari on OS X. OS X 10.8..10.8.3 has broken support for ECDHE-ECDSA ciphers.

SSL_OP_SSLEAY_080_CLIENT_DH_BUG

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_TLS_D5_BUG

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_TLS_BLOCK_PADDING_BUG

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS

Disables a countermeasure against a SSL 3.0/TLS 1.0 protocol vulnerability affecting CBC ciphers, which cannot be handled by some broken SSL implementations. This option has no effect for connections using other ciphers.

SSL_OP_TLSEXT_PADDING

Adds a padding extension to ensure the ClientHello size is never between 256 and 511 bytes in length. This is needed as a workaround for some implementations.

SSL_OP_ALL

Default set of options

SSL_OP_TLS_ROLLBACK_BUG

Disable version rollback attack detection.

During the client key exchange, the client must send the same information about acceptable SSL/TLS protocol levels as during the first hello. Some clients violate this rule by adapting to the server's answer. (Example: the client sends a SSLv2 hello and accepts up to SSLv3.1=TLSv1, the server only understands up to SSLv3. In this case the client must still use the same SSLv3.1=TLSv1 announcement. Some clients step down to SSLv3 with respect to the server's answer and violate the version rollback protection.)

SSL_OP_SINGLE_DH_USE

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_EPHEMERAL_RSA

As of OpenSSL 1.0.1k and 1.0.2, this option has no effect.

SSL_OP_CIPHER_SERVER_PREFERENCE

When choosing a cipher, use the server's preferences instead of the client preferences. When not set, the SSL server will always follow the clients preferences. When set, the SSLv3/TLSv1 server will choose following its own preferences. Because of the different protocol, for SSLv2 the server will send its list of preferences to the client and the client chooses.

SSL_OP_PKCS1_CHECK_1

As of OpenSSL 1.0.1 this option has no effect.

SSL_OP_PKCS1_CHECK_2

As of OpenSSL 1.0.1 this option has no effect.

SSL_OP_NETSCAPE_CA_DN_BUG

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_NO_SSLv2

As of OpenSSL 1.1.0 this option has no effect.

SSL_OP_NO_SSLv3

Do not use the SSLv3 protocol. As of OpenSSL 1.1.0, this option is deprecated

SSL_OP_NO_TLSv1

Do not use the TLSv1 protocol. As of OpenSSL 1.1.0, this option is deprecated

SSL_OP_NO_TLSv1_1

Do not use the TLSv1.1 protocol. As of OpenSSL 1.1.0, this option is deprecated

SSL_OP_NO_TLSv1_2

Do not use the TLSv1.2 protocol. As of OpenSSL 1.1.0, this option is deprecated

SSL_OP_NO_TLSv1_3

Do not use the TLSv1.3 protocol. As of OpenSSL 1.1.0, this option is deprecated

SSL_OP_NO_DTLSv1

Do not use the DTLSv1 protocol. As of OpenSSL 1.1.0, this option is deprecated

SSL_OP_NO_DTLSv1_2

Do not use the DTLSv1.2 protocol. As of OpenSSL 1.1.0, this option is deprecated

SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION

When performing renegotiation as a server, always start a new session (i.e., session resumption requests are only accepted in the initial handshake). This option is not needed for clients.

SSL_OP_NO_TICKET

Normally clients and servers will, where possible, transparently make use of RFC 4507 tickets for stateless session resumption.

If this option is set this functionality is disabled and tickets will not be used by clients or servers.

SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION

Allow legacy insecure renegotiation between OpenSSL and unpatched clients or servers. See SECURE RENEGOTIATION for more details.

SSL_OP_LEGACY_SERVER_CONNECT

Allow legacy insecure renegotiation between OpenSSL and unpatched servers _only_. See SECURE RENEGOTIATION for more details.

SSL_OP_NO_EXTENDED_MASTER_SECRET

Disable Extended master secret. Only available on OpenSSL 3.0.0 and later.

SSL_OP_CLEANSE_PLAINTEXT

Cleanse plaintext copies of data. Only available on OpenSSL 3.0.0 and later.

SSL_OP_ENABLE_KTLS

Enble support for Kernel TLS Only available on OpenSSL 3.0.0 and later

SSL_OP_IGNORE_UNEXPECTED_EOF

SSL_OP_ALLOW_CLIENT_RENEGOTIATION

SSL_OP_DISABLE_TLSEXT_CA_NAMES

SSL_OP_CISCO_ANYCONNECT

SSL_OP_NO_ANTI_REPLAY

SSL_OP_PRIORITIZE_CHACHA

SSL_OP_ALLOW_NO_DHE_KEX

SSL_OP_NO_ENCRYPT_THEN_MAC

SSL_OP_NO_QUERY_MTU

SSL_OP_COOKIE_EXCHANGE

SSL_OP_NO_COMPRESSION

SSL_OP_ENABLE_MIDDLEBOX_COMPAT

SSL_OP_NO_RENEGOTIATION

SSL_OP_CRYPTOPRO_TLSEXT_BUG

Instances

Show SSLOption

Defined in OpenSSL.SSL.Option

Methods

showsPrec :: Int -> SSLOption -> ShowS

show :: SSLOption -> String

showList :: [SSLOption] -> ShowS

Eq SSLOption

Defined in OpenSSL.SSL.Option

Methods

(==) :: SSLOption -> SSLOption -> Bool

(/=) :: SSLOption -> SSLOption -> Bool

Ord SSLOption

Defined in OpenSSL.SSL.Option

Methods

compare :: SSLOption -> SSLOption -> Ordering

(<) :: SSLOption -> SSLOption -> Bool

(<=) :: SSLOption -> SSLOption -> Bool

(>) :: SSLOption -> SSLOption -> Bool

(>=) :: SSLOption -> SSLOption -> Bool

max :: SSLOption -> SSLOption -> SSLOption

min :: SSLOption -> SSLOption -> SSLOption

SSL Exceptions

data SomeSSLException

The root exception type for all SSL exceptions.

Instances

Exception SomeSSLException

Defined in OpenSSL.Session

Methods

toException :: SomeSSLException -> SomeException

fromException :: SomeException -> Maybe SomeSSLException

displayException :: SomeSSLException -> String

Show SomeSSLException

Defined in OpenSSL.Session

Methods

showsPrec :: Int -> SomeSSLException -> ShowS

show :: SomeSSLException -> String

showList :: [SomeSSLException] -> ShowS

data ConnectionAbruptlyTerminated

The peer uncleanly terminated the connection without sending the "close notify" alert.

Instances

Exception ConnectionAbruptlyTerminated

Defined in OpenSSL.Session

Methods

toException :: ConnectionAbruptlyTerminated -> SomeException

fromException :: SomeException -> Maybe ConnectionAbruptlyTerminated

displayException :: ConnectionAbruptlyTerminated -> String

Show ConnectionAbruptlyTerminated

Defined in OpenSSL.Session

Methods

showsPrec :: Int -> ConnectionAbruptlyTerminated -> ShowS

show :: ConnectionAbruptlyTerminated -> String

showList :: [ConnectionAbruptlyTerminated] -> ShowS

Eq ConnectionAbruptlyTerminated

Defined in OpenSSL.Session

Methods

(==) :: ConnectionAbruptlyTerminated -> ConnectionAbruptlyTerminated -> Bool

(/=) :: ConnectionAbruptlyTerminated -> ConnectionAbruptlyTerminated -> Bool

data ProtocolError

A failure in the SSL library occurred, usually a protocol error.

Constructors

ProtocolError !String

Instances

Exception ProtocolError

Defined in OpenSSL.Session

Methods

toException :: ProtocolError -> SomeException

fromException :: SomeException -> Maybe ProtocolError

displayException :: ProtocolError -> String

Show ProtocolError

Defined in OpenSSL.Session

Methods

showsPrec :: Int -> ProtocolError -> ShowS

show :: ProtocolError -> String

showList :: [ProtocolError] -> ShowS

Eq ProtocolError

Defined in OpenSSL.Session

Methods

(==) :: ProtocolError -> ProtocolError -> Bool

(/=) :: ProtocolError -> ProtocolError -> Bool

Direct access to OpenSSL objects

data SSLContext_

withContext :: SSLContext -> (Ptr SSLContext_ -> IO a) -> IO a

Run the given action with the raw context pointer and obtain the lock while doing so.

data SSL_

withSSL :: SSL -> (Ptr SSL_ -> IO a) -> IO a

Run continuation with exclusive access to the underlying SSL object.