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Re: debcheckroot v2.0 released



  There are a few reasons why I believe that DANE / TLSA DNS RR answers are quite trustworthy:

* DNS responses are much faster than establishing a TCP connection (1.5RTT), usually only about 40ms also because DNS servers tend to be near the user if not provided by the ISP while the server you wanna contact is usually in another country or another federal state. As we know from the Snowden Revelations spoofing connections only works if the spoofed response is faster than the original response. My idea about it is that the NSA and related intelligence simply do not have an infrastructure to spoof DNS responses.

* There is a public/private key signing infrastructure for DANE as well but I consider that more secure than a gpg private key used on a system with emailing or web browsing. I believe it is much more hard to get into a server than is to get into a client.

  Finally DANE has been invented for the reason to restore trust in the internet - as it was there initially when there was no operation Quantum insert or similar operations. I´d believe the DANE system has been designed secure as to serve its purpose. Finally my own practical experience with DANE is very positive. It appeared to be the only way to prevent site spoofing:
https://lists.debian.org/debian-security/2020/01/threads.html
https://lists.debian.org/debian-security/2020/02/threads.html
https://lists.debian.org/debian-security/2020/03/threads.html

  The reason why browser developers have not adopted DANE yet is that they side with intelligence (secret services) as the following bug report shows me:
https://bugzilla.mozilla.org/show_bug.cgi?id=1606802

  I had also linked this report in my previous discussion at debian-security.


Finally I have forgotten about the most important reason why DANE is much more secure than other methods:

* There is a regular, secure and automatic key rotation for DANE. With GnuPG keys can be happily stolen as they remain valid for a year or more and as there is no secure way to redistribute a new key.

Concerning DoH/DoT I would rather believe these technologies to be detrimental as encryption adds an additional error prone overhead but does not contribute anything to the authenticity of the reply. Encryption can be a source of arbitrary code execution exploits if not implemented properly. Encrypting DNS would have other application purposes and makes sense as long as you use a proxy. If you connect directly hiding the domain name is ineffective because someone who spys at the connection also knows the IPs you connect to and via SNI the cleartext of the domain you surf at.



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