The question pretty much sums it up. Are ECDSA and ECDH available for mono? If they are not, will they be?
Microsoft .NET supports both,
http://msdn.microsoft.com/en-us/library/system.security.cryptography.ecdsacng.aspx
http://msdn.microsoft.com/en-us/library/system.security.cryptography.ecdiffiehellmancng.aspx
From both Mono source code and documentation you can see that ECDSA and ECDH are not supported, as the corresponding classes are missing,
https://github.com/mono/mono/tree/master/mcs/class/System.Core/System.Security.Cryptography
http://docs.go-mono.com/?link=N%3aSystem.Security.Cryptography
For Xamarin.iOS and Xamarin.Android which are derived from Mono, you might check if there are any native library to call.
You can try to use "The Legion of the Bouncy Castle". It's fully written in .NET and supports many signature and encryption algorithms. I found it a bit tricky to use, there's not a lof of documentation, but it works.
Try to find a NuGet package or visit their website:
来源:https://stackoverflow.com/questions/18116417/are-ecdsa-and-ecdh-available-for-mono