more security considerations

[thomas-fossati]

Fix #16

[henkbirkholz]

What about "caching" a TST before TTC or CTT? The TST basically tells at minimum "statement not younger than time in TST". By retrieving a TST and then using it later, you can shift that point "more into the past". That is probably is a threat, too?

[thomas-fossati]

What about "caching" a TST before TTC or CTT?

In CTT that can't happen unless you can predict the COSE signature, i.e., the content of the datum.

The TST basically tells at minimum "statement not younger than time in TST". By retrieving a TST and then using it later, you can shift that point "more into the past". That is probably is a threat, too?

Sorry, I don't understand this. You are making a similar point in #25 which I am also failing to grok. To me, a timestamp asserts the existence of a datum at least at the point in time when the timestamp for that datum is created. I cannot fathom an attack in which pushing the existence of the datum back in time is an attack on the intended use of the datum.

[henkbirkholz]

ltgm