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TACK is a nice improvement to TLS that keeps compatibility with the existing CA system. However, TACK only protects you after you've visited a site for the fir

by dcposch 13y ago

TACK is a nice improvement to TLS that keeps compatibility with the existing CA system. However, TACK only protects you after you've visited a site for the first time. If a person is targeted by any organization that can sign a fraudulent certificate before the first time they visit a site, then they are still vulnerable to MITM. Given that many countries have root CAs, many governments have this capability. Namecoin does not suffer from that issue. Namecoin and TACK solve different problems. One is an incremental improvement with backward capability; the other is a clean break that attempts to provide stronger guarantees. "you are vanishingly unlikely to do a better job of designing an encrypted channel than every cryptographer and protocol designer and software security person who has poured time into TLS" It pains me to see this kind of arrogant dismissal as the top comment so often. The author said nothing about designing his own protocol. He simply explained the problems with the CA system and the way Namecoin (specifically the DotBIT proposal) might solve those problems. This would simply add new functionality: supporting .bit URLS where the clients looks up the certificate through the blockchain, without trusting the CAs. After that first step, the encrypted channel implementation can be the same. And the blockchain concept (and even Namecoin's specific implementation) is shared with Bitcoin, which has been battle-tested quite thoroughly at this point.

tptacek 13y ago
TACK is a baby step towards a design idea Marlinspike called "Convergence", and I just call "updating the 1995 browser trust store UI to the standards of 2005". The idea that only members of the CABForum can run CAs is silly, especially when (a) many of those organizations are in fact beholden to governments and (b) some of them have actually sold root CA certs. There is no technical reason the ACLU should not be able to run run its own trust store, certifying alternate CAs that it is confident aren't corrupted, and revoking CAs when certificate pin errors make it clear that they have been. The UI to make that happen is very simple as well. My issue with things like distributed ledger verification is that TLS's problem isn't the crypto. The crypto should be kept boring; we're barely holding the crypto together as it stands. The problem with the TLS security model is browser UX. We can and should leave the protocol alone.
- y0ghur7_xxx 13y ago
  > We can and should leave the protocol alone. Nobody, not in the article and not in the post you replied to, sad that the protocol needs to be replaced. In fact, both say the exact opposite. I like your posts, and you clearly know what you are talking about, but this time it seems you don't discuss the article, but just hop in the discussion with random and not correlated, but true facts.
  - tptacek 13y ago
    I'm including the CA system in my definition of "the protocol".
    - y0ghur7_xxx 13y ago
      > I'm including the CA system in my definition of "the protocol". Well then, TACK changes "the protocol". As you know better than me it proposes changes to the TLS handshake and how CAs are verified.

by dcposch 13y ago

tptacek 13y ago

TACK is a baby step towards a design idea Marlinspike called "Convergence", and I just call "updating the 1995 browser trust store UI to the standards of 2005". The idea that only members of the CABForum can run CAs is silly, especially when (a) many of those organizations are in fact beholden to governments and (b) some of them have actually sold root CA certs. There is no technical reason the ACLU should not be able to run run its own trust store, certifying alternate CAs that it is confident aren't corrupted, and revoking CAs when certificate pin errors make it clear that they have been. The UI to make that happen is very simple as well. My issue with things like distributed ledger verification is that TLS's problem isn't the crypto. The crypto should be kept boring; we're barely holding the crypto together as it stands. The problem with the TLS security model is browser UX. We can and should leave the protocol alone.

y0ghur7_xxx 13y ago
> We can and should leave the protocol alone. Nobody, not in the article and not in the post you replied to, sad that the protocol needs to be replaced. In fact, both say the exact opposite. I like your posts, and you clearly know what you are talking about, but this time it seems you don't discuss the article, but just hop in the discussion with random and not correlated, but true facts.
- tptacek 13y ago
  I'm including the CA system in my definition of "the protocol".
  - y0ghur7_xxx 13y ago
    > I'm including the CA system in my definition of "the protocol". Well then, TACK changes "the protocol". As you know better than me it proposes changes to the TLS handshake and how CAs are verified.