[Cryptography] Name for a specific type of preimage resistance

[Peter Gutmann]

Stephan Neuhaus <stephan.neuhaus at zhaw.ch> writes:

>I don't know of any name (but I'm not a cryptographer). But why is that even
>an issue? Once you keep only hash(x) but not x, wouldn't ANY preimage do?

The specific problem here is "given hash( secret_value ), can you recover
secret_value from its hash"?  Preimage resistance is the more general "given
hash( x ), can you find anything at all that produces that hash"?

(Note that this is an abstract concept, not getting bogged down into specifics
of what form secret_value has, how it's encoded, whether the hash is being
used in a KDF or PRF or as an HMAC or whatever, additional complications
introduced by input width > hash output width, etc).

In the absence of any actual name, could I suggest "singular preimage
resistance"?

Peter.