Update osrng.cpp

[Kronix69]

Added the possibility of using Microsoft's default RNG provider, removes the need to acquire a provider (which solves the problem of not having an available provider and also saves resources)

[noloader]

Thanks @Kronix69.

Where is CRYPTOPP_DEFAULT_AES_PROVIDER configured? I only see it used in the change request.

[Kronix69]

I momentarily left it like that so the user can enable it if they desire and so if you guys believed it to be better to enable it by default

[Kronix69]

We could completely remove the need for a provider, I haven't encountered any issues with using the default provider so we could just erase the whole acquiring of a provider, remove the if defined for CRYPTOPP_DEFAULT_AES_PROVIDER and just make it be the standard

[Kronix69]

Hey @noloader, any status on merging? I changed the code and applied the changes without the #ifdef.

[wyattoday]

BCRYPT_RNG_ALG_HANDLE is only defined (and usable) on Windows 10 and newer. So, this will fail if targeting older versions of Windows.

You could conditionally define BCRYPT_RNG_ALG_HANDLE and do a runtime detection of the version and optionally create the MicrosoftCryptoProvider() (and use that handle) or use the BCRYPT_RNG_ALG_HANDLE depending on what version of Windows the end-user is on.

[Kronix69]

BCRYPT_RNG_ALG_HANDLE is only defined (and usable) on Windows 10 and newer. So, this will fail if targeting older versions of Windows.

You could conditionally define BCRYPT_RNG_ALG_HANDLE and do a runtime detection of the version and optionally create the MicrosoftCryptoProvider() (and use that handle) or use the BCRYPT_RNG_ALG_HANDLE depending on what version of Windows the end-user is on.

Done, I instead used the WINVER define which specifies the Windows version to check for Windows 10 and higher.

[Kronix69]

Any status on the merge?

[Kronix69]

Nevermind I realised the issue with static checking, will devise a way to runtime check