Re: Handling of unverified data and media
Roman Shpount <[email protected]>
| Newsgroups | gmane.ietf.mmusic |
|---|---|
| Message-ID | <CAD5OKxvwV38dJXR3mYSiQEnNoX3X7nfMY2hBe1S4kxj7h6WZWA@mail.gmail.com> |
Peter, Any comments on the ICE Lite scenario? I did see it in the wild. Regards, _____________ Roman Shpount On Thu, Mar 30, 2017 at 9:11 PM, Roman Shpount <[email protected]> wrote: > Peter, > > What about ICE lite? If ICE lite sends an offer to WebRTC end point, it > can get DTLS ClientHello before it got the answer response from the WebRTC > end point. Since ICE lite client does not send ICE requests before sending > data, it will respond with ServerHello and establish the connection. At > this point data can be sent to it before the answer arrives and fingerprint > can be verified. > > I think the right answer to this situation is not to send ServerHello > until answer and fingerprint is received. ClientHello should be buffered > and only handled when answer is received. > > Regards, > > _____________ > Roman Shpount > > On Thu, Mar 30, 2017 at 7:40 PM, Peter Thatcher <[email protected]> > wrote: > >> Bernard, you are right that this is possible with ORTC, even though I >> think it's impossible with WebRTC. But that's clearly out of scope for the >> MMUSIC WG. Perhaps the right forum to discuss Cullen's 1-800-fedex use >> case is in the context of ORTC (or WebRTC NV). >> >> On Thu, Mar 30, 2017 at 3:50 PM Martin Thomson <[email protected]> >> wrote: >> >>> These both sound like legitimate cases where ICE can precede >>> signaling. I would recommend that the W3C think carefully about >>> whether they might like to accept (potentially) invalid data before we >>> spend a whole lot more time on the issue. >>> >>> On 30 March 2017 at 17:11, Bernard Aboba <[email protected]> >>> wrote: >>> > The unverified media scenarios seem to depend on ICE connectivity being >>> > bi-directionally enabled so as to permit the DTLS negotiation to >>> proceed in >>> > advance of remote fingerprint arrival. If ICE candidates are signaled >>> > separately from the DTLS fingerprint exchange it might be feasible, >>> such as >>> > in ORTC signaling where the ICE parameters are exchanged before the >>> > DtlsParameters. >>> > >>> > At the last WebRTC interim a scenario involving PRANSWER and Trickle >>> ICE was >>> > presented. In the scenario, the PRANSWER included a fingerprint, but >>> > possibly one which did not match the certificate provided in DTLS >>> unlike the >>> > final answer. I do not see how this could work but perhaps I am missing >>> > something. >>> > >>> > On Mar 30, 2017, at 14:14, Peter Thatcher <[email protected]> >>> wrote: >>> > >>> > We have a mailing list discussion (here), a bug >>> > (https://github.com/w3c/webrtc-pc/issues/849) and a PR >>> > (https://github.com/w3c/webrtc-pc/pull/1026#issuecomment-279238215) >>> about >>> > this. I've copied the following comments to the latter two, so I'm >>> adding >>> > them here as well. >>> > >>> > TL;DR: I don't think unverified media is compatible with ICE+DTLS. >>> Here is >>> > why (you can go see the bug, too): >>> > >>> > You can receive DTLS from the remote side before receiving the remote >>> > description (and thus fingerprint). This happens if the remote side >>> sends an >>> > ICE connectivity check and the local side sends a response and then the >>> > remote side sends a DTLS packet. >>> > >>> > You cannot send DTLS from the local side before receiving the remote >>> > description (and thus fingerprint). This is because you can't send an >>> ICE >>> > connectivity check until you have the remote ICE ufrag and pwd, and >>> thus >>> > can't get an ICE connectivity check response, and thus can't send >>> DTLS. This >>> > is because you can't send anything other than ICE until you get an ICE >>> > connectivity check response. >>> > >>> > Since you can't send DTLS, you can't complete the handshake, and thus >>> can't >>> > extract the SRTP key. >>> > >>> > >>> > Maybe I'm missing something, but I think this is impossible. >>> > >>> > On Sat, Mar 25, 2017 at 1:12 PM Cullen Jennings <[email protected]> wrote: >>> >> >>> >> >>> >> On Mar 13, 2017, at 3:44 PM, Christer Holmberg >>> >> <[email protected]> wrote: >>> >> >>> >> My question is: is this something that’s causing problems in real >>> >> deployments, and requires a change in the standard? >>> >> >>> >> >>> >> 1-800 go fedex. See webrtc requirements documents from many years ago. >>> >> _______________________________________________ >>> >> mmusic mailing list >>> >> [email protected] >>> >> https://www.ietf.org/mailman/listinfo/mmusic >>> > >>> > _______________________________________________ >>> > mmusic mailing list >>> > [email protected] >>> > https://www.ietf.org/mailman/listinfo/mmusic >>> > >>> > >>> > _______________________________________________ >>> > mmusic mailing list >>> > [email protected] >>> > https://www.ietf.org/mailman/listinfo/mmusic >>> > >>> >> >> _______________________________________________ >> mmusic mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/mmusic >> >> > _______________________________________________ mmusic mailing list [email protected] https://www.ietf.org/mailman/listinfo/mmusic