tor/changes/bug8121

  o Minor features:
    - Clear the high bit on curve25519 public keys before passing them to
      our backend, in case we ever wind up using a backend that doesn't do
      so itself. If we used such a backend, and *didn't* clear the high bit,
      we could wind up in a situation where users with such backends would
      be distinguishable from users without. Fix for bug 8121; bugfix on
      0.2.4.8-alpha.
Tolerate curve25519 backends where the high bit of the pk isn't ignored Right now, all our curve25519 backends ignore the high bit of the public key. But possibly, others could treat the high bit of the public key as encoding out-of-bounds values, or as something to be preserved. This could be used to distinguish clients with different backends, at the cost of killing a circuit. As a workaround, let's just clear the high bit of each public key indiscriminately before we use it. Fix for bug 8121, reported by rransom. Bugfix on 0.2.4.8-alpha. 2013-02-04 18:50:01 +01:00			`o Minor features:`
			`- Clear the high bit on curve25519 public keys before passing them to`
			`our backend, in case we ever wind up using a backend that doesn't do`
			`so itself. If we used such a backend, and didn't clear the high bit,`
			`we could wind up in a situation where users with such backends would`
			`be distinguishable from users without. Fix for bug 8121; bugfix on`
			`0.2.4.8-alpha.`