[Info-vax] SSH/SCP sessions hanging for 7 minutes while reading from "/dev/random"

[Stephen Hoffman]

On 2021-09-30 05:39:35 +0000, Lawrence D’Oliveiro said:

> Lack of system entropy to keep /dev/random fed? This is why we have 
> /dev/urandom, for all but the most critical uses.

Within OpenVMS, there is no pseudo-device that provides either 
pseudo-random number generation or cryptographic pseudo-random number 
generation.

That driver (which would be unusual on OpenVMS), and system service 
APIs (which are common) have been proposed.  Kernel TLS has been 
proposed, too.

OpenVMS itself hasn't more generally adopted CPRNG support at its 
existing APIs, with the common APIs producing PRNGs.

Reasons not to update have been found, as per usual with OpenVMS upward 
compatibility.

For one of the previous discussions of OpenVMS and CPRNGs and of 
seeding an entropy pool: 
https://groups.google.com/g/comp.os.vms/c/BmIXV0gN3n8/m/mETohq6qAgAJ

Within recent Linux kernel versions, /dev/random and /dev/urandom are 
the same underneath, neither will block post-initialization, and both 
will produce the same CPRNG values.



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