HTTPS Everywhere? This Email Service Gives You DANE, Too
blog.tutanota.de
HTTPS Everywhere? This Email Service Gives You DANE, Too
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Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#2> SSL makes man-in-the-middle attacks all too easy. Every owner of root certificates that is certificate authorities, secret services and big Internet providers can intervene between user and server to intercept confidential information or even manipulate it.
This problem doesn't go away with DNS (in fact without DNS-Sec it's as good as a self-signed cert) and with DNSSec, state actors/root delegates can still act maliciously.
Granted, I still think it's a better option than the current CA system, it just doesn't magically make certain kind of attacks go away.
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#3Soo, instead of having DNS + CA to hack now we just need to hack the DNS ?
That seems like a single point of failure to me.
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#4Doesn't this just swap the existing set of trusted CAs (used to bootstrap TLS trust) for a new set of trusted DNS root operators (used to bootstrap DNSSEC trust)?
Surely if you're worried about state actors, this is no help?
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#5Some reasons why I do not like tutanota:
* They say the combination of AES-128 and 2k RSA keys is secure
* The private key is stored on their servers (password needs to be set, but if security hinges on the private key password...)
* The website contains FUD (e.g. the FAQ [1])
* They have been sending UBE with loads of FUD to promote their services
[1] https://tutanota.de/#!faq (the language switch is all the way down at the bottom)
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#6I also have support for DANE on grepular.com, for web and also MX. I've only been doing it for MX for a couple of weeks though. Postfix now supports it.
edit: This is just a hobby domain though.
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#7Soo, instead of having DNS + CA to hack now we just need to hack the DNS ? That seems like a single point of failure to me.
"DNS + CA" ? Don't you just mean "CA". And when you say "CA", don't you mean, "1 out of hundreds of CAs" ?
Besides there are no CA's for SMTP anyway. Encryption is entirely opportunistic, and self-signed certs are just as trusted as ones signed by one of the CA's that people use for web traffic.
The difference with DANE+SMTP is, all of a sudden a sending server will know that it must use TLS or not send the message. And the cert it receives must match the one published in the DNS. Not just one that is signed by one of any hundreds of CAs.
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#8Doesn't this just swap the existing set of trusted CAs (used to bootstrap TLS trust) for a new set of trusted DNS root operators (used to bootstrap DNSSEC trust)? Surely if you're worried about state actors, this is no help?
Today, SMTP can be trivially MITM'd by anyone on a network, not just state actors, even if TLS is supported. All you have to do is remove "STARTTLS" from the servers EHLO response and then everything is in the clear.
Forcing a MITM to compromise DNSSEC before they can read the cleartext is a worthwhile barrier to add IMO.
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#9Some reasons why I do not like tutanota: * They say the combination of AES-128 and 2k RSA keys is secure * The private key is stored on their servers (password needs to be set, but if security hinges on the private key password...) * The website contains FUD (e.g. the FAQ [1]) * They have been sending UBE with loads of FUD to promote their services [1] https://tutanota.de/#!faq (the language switch is all the way dow…
Yep. Note also that DANE (as they mention) currently depends on the full-blown DNSSEC stack to be useful. However, the full-blown DNSSEC stack suffers from many technical and design-related problems:
http://www.thoughtcrime.org/blog/ssl-and-the-future-of-authe...
http://ianix.com/pub/dnssec-outages.html
Disclaimer: I work on DNSChain, a blockchain-based alternative to DNSSEC & X.509. Note that DNSChain does support blockchain-authenticated DANE TLSA records. In the future, DNSSEC's SIG record may be used to provide MITM-proof verification of the validity of that TLSA record for DNS-based apps.
Re: HTTPS Everywhere? This Email Service Gives You DANE, Too
#10Some reasons why I do not like tutanota: * They say the combination of AES-128 and 2k RSA keys is secure * The private key is stored on their servers (password needs to be set, but if security hinges on the private key password...) * The website contains FUD (e.g. the FAQ [1]) * They have been sending UBE with loads of FUD to promote their services [1] https://tutanota.de/#!faq (the language switch is all the way dow…
Are AES-128 and 2k RSA keys not secure?
I know 1k RSA isn't secure, but I thought 2k was.