Apache Reference: mod_ssl, SSLRandomSeed

SSLRandomSeed

Pseudo-Random Number Generator (PRNG) Seeding Source
Syntax: SSLRandomSeed context source [bytes]
Example: SSLRandomSeed startup builtin
Since: Apache 1.3

This directive configures one or more sources for seeding the Pseudo-Random Number Generator (PRNG) in OpenSSL at start-up (context is ``start==up'') or just before a new SSL connection is established (context is ``con==nect''). It can be used only in the global server context, because PRNG is a global facility. Several source variants are available. The ``builtin'' option uses an existing internal seeding source that consumes minimal CPU cycles under runtime and hence can be used without drawbacks.

In the ``file:filepath'' option, the seeding data are read from filepath, which is especially interesting with an existing F device. The source argument can also take the form ``exec:filepath'', where filepath is treated as a program, and executed and the seeding data are read from its stdout. Optionally, a bytes argument can be given that forces mod_ssl to read only the specified amount of data instead of all data until end of file is reached.