HsOpenSSL-0.10.4: Partial OpenSSL binding for Haskell

Safe HaskellNone



HsOpenSSL is an OpenSSL binding for Haskell. It can generate RSA and DSA keys, read and write PEM files, generate message digests, sign and verify messages, encrypt and decrypt messages.

Please note that this project has started at the time when there were no pure-Haskell implementations of TLS. Now there is tls package (http://hackage.haskell.org/package/tls), which looks pretty saner than HsOpenSSL especially for initialisation and error handlings. So PHO (the initial author of HsOpenSSL) wants to encourage you to use and improve the tls package instead as long as possible. The only problem is that the tls package has not received as much review as OpenSSL from cryptography specialists yet, thus we can't assume it's secure enough.

Features that aren't (yet) supported:

SSL network connection
ssl(3) functionalities aren't fully covered yet. See OpenSSL.Session.
Complete coverage of Low-level API to symmetric ciphers
Only high-level APIs (EVP and BIO) are fully available. But I believe no one will be lost without functions like DES_set_odd_parity.
Low-level API to asymmetric ciphers
Only a high-level API (EVP) is available. But I believe no one will complain about the absence of functions like RSA_public_encrypt.
Key generation of Diffie-Hellman algorithm
Only RSA and DSA keys can currently be generated.
X.509 v3 extension handling
It should be supported in the future.
Low-level API to message digest functions
Just use EVP instead of something like MD5_Update.
API to PKCS#12 functionality
It should be covered someday.
BIO isn't needed because we are Haskell hackers. Though HsOpenSSL itself uses BIO internally.
ENGINE cryptographic module
The default implementations work very well, don't they?



withOpenSSL :: IO a -> IO aSource

Computation of withOpenSSL action initializes the OpenSSL library as necessary, and computes action. Every application that uses HsOpenSSL must wrap any operations involving OpenSSL with withOpenSSL, or they might crash:

 module Main where
 import OpenSSL

 main :: IO ()
 main = withOpenSSL $
        do ...

Since, withOpenSSL is safe to be applied redundantly. Library authors may wish to wrap their functions not to force their users to think about initialization:

 get :: URI -> IO Response
 get uri = withOpenSSL $ internalImplementationOfGet uri