Re: [rtcweb] AVPF [was: Encryption mandate (and offer/answer)]
Dzonatas Sol <dzonatas@gmail.com> Fri, 09 September 2011 19:42 UTC
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Date: Fri, 09 Sep 2011 12:46:12 -0700
From: Dzonatas Sol <dzonatas@gmail.com>
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Subject: Re: [rtcweb] AVPF [was: Encryption mandate (and offer/answer)]
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On 09/09/2011 12:23 PM, Alan Johnston wrote: > Ekr is correct. If we allow RTP, which I think is a mistake, then > there is always a downgrade attack > Two encrypted states that negotiate with each other is not an attack. There is just no obvious equality between the two "when introduced." Let the federated servers introduce them; otherwise, it's browser to browser with the bigger unknown. Maybe QoS can include syllabic gain performance measurements to test that continuously, yet that is forward-thinking for many despite known proof. > My point was that if we must support insecure media, we could avoid > the complexity of CapNeg by not requiring a single pass non-secure > media negotiation. > > - Alan - > > On Fri, Sep 9, 2011 at 1:35 PM, Eric Rescorla<ekr@rtfm.com> wrote: > >> On Fri, Sep 9, 2011 at 11:11 AM, Matthew Kaufman >> <matthew.kaufman@skype.net> wrote: >> >>> On 9/9/11 10:47 AM, Alan Johnston wrote: >>> >>>> � The default will be SRTP - this can be >>>> expressed in SDP without CapNeg. �Should the RTCWEB clients choose to >>>> instead negotiate RTP, then this could be done with a second SDP >>>> Offer/Answer exchange. >>>> >>> I believe you've just designed a downgrade vulnerability. >>> >> Unless I'm missing something, if you (a) support an insecure mode and (b) allow >> negotiation of insecure vs. secure, there's not really any way to >> avoid a downgrade >> issue; the attacker can always pretend not to support security and how do you >> know better? Obviously, it helps if you can negotiate the use or non-use of >> media security over a secure-ish signaling channel, but that doesn't reduce >> the threat from the signaling service. >> >> Best, >> -Ekr >> >> > _______________________________________________ > rtcweb mailing list > rtcweb@ietf.org > https://www.ietf.org/mailman/listinfo/rtcweb > > -- --- http://twitter.com/Dzonatas_Sol --- Web Development, Software Engineering Ag-Biotech, Virtual Reality, Consultant
- [rtcweb] Remote recording - RTC-Web client acting… Elwell, John
- Re: [rtcweb] Remote recording - RTC-Web client ac… Stefan Håkansson LK
- Re: [rtcweb] Remote recording - RTC-Web client ac… Ravindran Parthasarathi
- Re: [rtcweb] Remote recording - RTC-Web client ac… Paul Kyzivat
- Re: [rtcweb] Remote recording - RTC-Web client ac… Dan York
- Re: [rtcweb] Remote recording - RTC-Web client ac… Elwell, John
- Re: [rtcweb] Remote recording - RTC-Web client ac… Olle E Johansson
- Re: [rtcweb] Remote recording - RTC-Web client ac… Dan York
- Re: [rtcweb] Remote recording - RTC-Web client ac… Hutton, Andrew
- Re: [rtcweb] Remote recording - RTC-Web client ac… Igor Faynberg
- [rtcweb] SIP MUST NOT be used in browser?[was RE:… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] Remote recording - RTC-Web client ac… Randell Jesup
- Re: [rtcweb] Remote recording - RTC-Web client ac… Elwell, John
- Re: [rtcweb] Remote recording - RTC-Web client ac… Hutton, Andrew
- Re: [rtcweb] Remote recording - RTC-Web client ac… Harald Alvestrand
- Re: [rtcweb] Remote recording - RTC-Web client ac… Dzonatas Sol
- Re: [rtcweb] Remote recording - RTC-Web client ac… Igor Faynberg
- Re: [rtcweb] Remote recording - RTC-Web client ac… Paul Kyzivat
- Re: [rtcweb] Remote recording - RTC-Web client ac… Harald Alvestrand
- Re: [rtcweb] Remote recording - RTC-Web client ac… Elwell, John
- Re: [rtcweb] Remote recording - RTC-Web client ac… Matthew Kaufman
- Re: [rtcweb] Remote recording - RTC-Web client ac… Dzonatas Sol
- Re: [rtcweb] Remote recording - RTC-Web client ac… Ravindran Parthasarathi
- Re: [rtcweb] Remote recording - RTC-Web client ac… Timothy B. Terriberry
- Re: [rtcweb] Remote recording - RTC-Web client ac… Ravindran Parthasarathi
- Re: [rtcweb] Remote recording - RTC-Web client ac… Ravindran Parthasarathi
- Re: [rtcweb] Remote recording - RTC-Web client ac… Matthew Kaufman
- Re: [rtcweb] Remote recording - RTC-Web client ac… Matthew Kaufman
- Re: [rtcweb] Remote recording - RTC-Web client ac… Bernard Aboba
- Re: [rtcweb] Remote recording - RTC-Web client ac… Robert O'Callahan
- Re: [rtcweb] Remote recording - RTC-Web client ac… Robert O'Callahan
- Re: [rtcweb] Remote recording - RTC-Web client ac… Elwell, John
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Olle E. Johansson
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Asveren, Tolga
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Justin Uberti
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Paul Kyzivat
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Olle E. Johansson
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Roman Shpount
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Harald Alvestrand
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Markus.Isomaki
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Randell Jesup
- [rtcweb] Encryption mandate Randell Jesup
- Re: [rtcweb] Encryption mandate Olle E. Johansson
- Re: [rtcweb] Encryption mandate Dzonatas Sol
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Olle E. Johansson
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Olle E. Johansson
- Re: [rtcweb] Encryption mandate Dzonatas Sol
- Re: [rtcweb] Encryption mandate (and offer/answer) Jonathan Lennox
- Re: [rtcweb] Encryption mandate Christopher Blizzard
- Re: [rtcweb] Encryption mandate Igor Faynberg
- Re: [rtcweb] Encryption mandate Dzonatas Sol
- Re: [rtcweb] Encryption mandate Paul Kyzivat
- Re: [rtcweb] Encryption mandate Igor Faynberg
- Re: [rtcweb] Encryption mandate Randell Jesup
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Matthew Kaufman
- Re: [rtcweb] Encryption mandate (and offer/answer) Randell Jesup
- Re: [rtcweb] Encryption mandate Matthew Kaufman
- Re: [rtcweb] Encryption mandate Randell Jesup
- Re: [rtcweb] Encryption mandate Dzonatas Sol
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Silvia Pfeiffer
- Re: [rtcweb] Encryption mandate Christopher Blizzard
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] Encryption mandate Olle E. Johansson
- Re: [rtcweb] Encryption mandate Olle E. Johansson
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Olle E. Johansson
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Silvia Pfeiffer
- Re: [rtcweb] Encryption mandate Randell Jesup
- [rtcweb] AVPF [was: Encryption mandate (and offer… Christer Holmberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Harald Alvestrand
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Olle E. Johansson
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Silvia Pfeiffer
- Re: [rtcweb] Encryption mandate Michael Procter
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Tim Panton
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Olle E. Johansson
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Jonathan Lennox
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Tim Panton
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- [rtcweb] Meeting Bridge and Webex link for Sept 8… Sohel Khan
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Harald Alvestrand
- Re: [rtcweb] Encryption mandate Paul Kyzivat
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Bernard Aboba
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Harald Alvestrand
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Roman Shpount
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Roman Shpount
- Re: [rtcweb] Encryption mandate Paul Kyzivat
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Paul Kyzivat
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] Encryption mandate Christopher Blizzard
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Justin Uberti
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Peter Saint-Andre
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Igor Faynberg
- Re: [rtcweb] SIP MUST NOT be used in browser? Aaron Clauson
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Justin Uberti
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Alan Johnston
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Justin Uberti
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Matthew Kaufman
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Eric Rescorla
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Justin Uberti
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Alan Johnston
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Roman Shpount
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Christer Holmberg
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Christer Holmberg
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Randell Jesup
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Justin Uberti
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Paul Kyzivat
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Olle E. Johansson
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Olle E. Johansson
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Olle E. Johansson
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Roman Shpount
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Matthew Kaufman
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Roman Shpount
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Matthew Kaufman
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Bernard Aboba
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Christer Holmberg
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Paul Kyzivat
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Randell Jesup
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Stefan Håkansson LK
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Hadriel Kaplan
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Timothy B. Terriberry
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dzonatas Sol
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser? Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Roman Shpount
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Roman Shpount
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Roman Shpount
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Stefan Håkansson LK
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Stefan Håkansson LK
- [rtcweb] SIP vs Websocket in RTCWeb [was RE: SIP … Ravindran Parthasarathi
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Matthew Kaufman
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Matthew Kaufman
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… DRAGE, Keith (Keith)
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Muthu Arul Mozhi Perumal (mperumal)
- Re: [rtcweb] SIP vs Websocket in RTCWeb [was RE: … Peter Saint-Andre
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Paul Kyzivat
- Re: [rtcweb] SIP vs Websocket in RTCWeb [was RE: … Dzonatas Sol
- Re: [rtcweb] SIP vs Websocket in RTCWeb [was RE: … Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Jozsef Vass
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Roman Shpount
- Re: [rtcweb] SIP vs Websocket in RTCWeb [was RE: … Peter Saint-Andre
- [rtcweb] signaling protocol SHANMUGALINGAM SIVASOTHY
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Hadriel Kaplan
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Hadriel Kaplan
- Re: [rtcweb] SIP MUST NOT be used in browser? Tim Panton
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Tim Panton
- Re: [rtcweb] SIP MUST NOT be used in browser? Olle E. Johansson
- Re: [rtcweb] SIP MUST NOT be used in browser? Ravindran Parthasarathi
- Re: [rtcweb] SIP MUST NOT be used in browser?[was… Muthu Arul Mozhi Perumal (mperumal)
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dan Wing
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Tim Panton
- Re: [rtcweb] AVPF [was: Encryption mandate (and o… Dan Wing