There are some loops of the form
for (i=1;i<1;++i) ...
And of course, if the loop index is initialized to 1, it will never
be less than 1, and the loop body will never be executed. This
upsets coverity.
Patch fixes CID 1221543 and 1221542
When size_t is the most memory you can have, make sure that things
referring to real parts of memory are size_t, not uint64_t or off_t.
But not on any released Tor.
This implementation allows somebody to add a blinding factor to a
secret key, and a corresponding blinding factor to the public key.
Robert Ransom came up with this idea, I believe. Nick Hopper proved a
scheme like this secure. The bugs are my own.
For proposal 228, we need to cross-certify our identity with our
curve25519 key, so that we can prove at descriptor-generation time
that we own that key. But how can we sign something with a key that
is only for doing Diffie-Hellman? By converting it to the
corresponding ed25519 point.
See the ALL-CAPS warning in the documentation. According to djb
(IIUC), it is safe to use these keys in the ways that ntor and prop228
are using them, but it might not be safe if we start providing crazy
oracle access.
(Unit tests included. What kind of a monster do you take me for?)
This is another case where DJB likes sticking the whole signature
prepended to the message, and I don't think that's the hottest idea.
The unit tests still pass.
We might use libsodium or ed25519-donna later on, but for now, let's
see whether this is fast enough. We should use it in all cases when
performance doesn't matter.
