I need to compute the hash of a byte array in a Portable Library.

I'm trying to find an equivalent of System.Security.Cryptography.SHA256Managed for my Portable library targeting .NET 4.5 + win 8 + WP 8.0 .

I tried the PclContrib but it seems I can't install it for a library targeting those platforms.

Is there any library providing hash algorithms implementations which can be referenced in the context of a Portable Library?

Thanks