What is the purpose of the
RANDFILE in an OpenSSL configuration file (specifically, the
ca section)? The man page entry,
config, just describes this as:
At startup the specified file is loaded into the random number generator, and at exit 256 bytes will be written to it.
But I can't tell how OpenSSL uses it. Does OpenSSL use it and only it for randomness, or is it just a salt for randomness taken from elsewhere? Do I need to include it every time, and if so, how much data should be in it?
Would it confer any security advantage to save output from
openssl rand to this file?