How insecure is using /dev/random for entropy generation?

[Robert J. Hansen]

On 3/30/2013 9:50 PM, Anthony Papillion wrote:
> I meed to generate a new key and want to make sure I create enough
> entropy to make the key secure. My normal method is to type on the
> keyboard, start large programs, etc. But a friend suggested that I use
> /dev/random.
> 
> Is this suitable for creating a PGP key? I've got concerns.

By default, GnuPG uses RNGs that are as high-quality as the operating
system provides.  However, since there's no standard RNG across
operating systems, GnuPG has no standard RNG, either.  On Win32 GnuPG
uses the Win32 API and CryptGenRandom; on many UNIXes it uses
/dev/random; I don't know what the OpenVMS port uses but I rather doubt
it's either /dev/random or CryptGenRandom.  :)

The best advice I can give you is "use whatever GnuPG uses by default
for your operating system."  It's the default for a reason: namely, it's
safe and known to work well.  :)