- From: Richard Barnes <rbarnes@mozilla.com>
- Date: Wed, 2 Dec 2015 09:54:58 -0500
- To: Florian Bösch <pyalot@gmail.com>
- Cc: Aymeric Vitte <vitteaymeric@gmail.com>, Brad Hill <hillbrad@gmail.com>, "Web Applications Working Group WG (public-webapps@w3.org)" <public-webapps@w3.org>, "public-webappsec@w3.org" <public-webappsec@w3.org>
- Message-ID: <CAOAcki8U8fY79i+7xhkRYDwSCKO+1RCExEPEv9x9t9O_jYvpsA@mail.gmail.com>
On Wed, Dec 2, 2015 at 9:36 AM, Florian Bösch <pyalot@gmail.com> wrote: > 1) Encryption between Alice and Bob by means of an asymmetric > public/private key exchange protocol cannot be secure if both also exchange > the keys and none has a method to verify the keys they got are the correct > ones. Chuck who might control the gateway over which either Alice or Bob > communicate can simply substitute his own public key for either of the two. > The whole point of certificates is that the sought out endpoint can provide > a set of credentials that're signed by a certificate authority, which is in > a chain of trust up to the root authority which is implicitly trusted. > > 2) You cannot obtain the benefits of UDP (out of order packages as fast as > they come) and yet retain the benefits of asymmetric public/private key > encryption schemes which rely on packages arriving in order. Attempting to > get both will result in detrimental performance or non existent security. > I think that if you read the DTLS spec, you'll see that it handles reordering just fine. https://tools.ietf.org/html/rfc6347#section-3.2.2 > > On Wed, Dec 2, 2015 at 2:05 PM, Aymeric Vitte <vitteaymeric@gmail.com> > wrote: > >> >> >> Le 02/12/2015 13:18, Florian Bösch a écrit : >> > On Wed, Dec 2, 2015 at 12:50 PM, Aymeric Vitte <vitteaymeric@gmail.com >> > <mailto:vitteaymeric@gmail.com>> wrote: >> > >> > Then you should follow your rules and apply this policy to WebRTC, >> ie >> > allow WebRTC to work only with http. >> > >> > >> > Just as a sidenote, WebRTC also does UDP and there's no TLS over UDP. >> > Also WebRTC does P2P, and there's no certificates/authorities there (you >> > could encrypt, but I don't think it does even when using TCP/IP (which >> > it doesn't in case of streaming video over UDP). >> >> See https://github.com/Ayms/node-Tor#security, WebRTC uses DTLS with >> self-signed certifcates + a third party mechanism supposed to secure the >> connection. >> >> As a matter of fact this is almost exactly the same mechanism used by >> the Tor network, where the CERTS cells use the long term ID key of a Tor >> node to make sure that you are discussing with that one. >> >> This does not prevent of course from discussing with a malicious node >> not identified as such with valid long term ID keys, which is not a >> problem for Tor (but is a problem for WebRTC), as long as it behaves as >> expected, and if it does not, this will be detected. >> >> The above mechanism is specific to the Tor network, for other uses of >> the Tor protocol an alternative is explained here: >> https://github.com/Ayms/node-Tor#pieces-and-sliding-window for WebRTC >> >> And again, adding a TLS layer on top of all this is of complete no use. >> >> -- >> Get the torrent dynamic blocklist: http://peersm.com/getblocklist >> Check the 10 M passwords list: http://peersm.com/findmyass >> Anti-spies and private torrents, dynamic blocklist: >> http://torrent-live.org >> Peersm : http://www.peersm.com >> torrent-live: https://github.com/Ayms/torrent-live >> node-Tor <https://github.com/Ayms/torrent-livenode-Tor> : >> https://www.github.com/Ayms/node-Tor >> GitHub : https://www.github.com/Ayms >> > >
Received on Wednesday, 2 December 2015 14:55:32 UTC