Lennart Poettering wrote:
As mentioned before: systemd itself already needs entropy itself (it
assigns a random 128bit id to each service invocation, dubbed the
"invocation ID" of it, and it generates the machine ID and seeds its
hash table hash functions)
Given that access to entropy during early boot is so problematic,
hardware-dependent and full of catch-22s, it seems to me that an init
system should use the entropy pool only if it really must.
With that in mind, could you explain why the invocation ID and the hash
tables need to be cryptographically secure? Why is rand or a simple
serial number not good enough? I never heard that lack of a
cryptographically secure invocation ID was a big security problem
before SystemD.
Björn Persson