4 ms·

You misunderstand. You're defining trust as trust that the entity is who the entity claims to be in societal space. But this is unnecessary. All that needs t

by me1010 12y ago

You misunderstand. You're defining trust as trust that the entity is who the entity claims to be in societal space. But this is unnecessary. All that needs to be trusted is that the claimed domain owner is the domain owner. It doesn't matter who that entity is in societal space - just cryptographic space. Each domain is its own CA. And the registrar doesn't need to be trusted at all. All it is doing is dolling out domain names to public keys. There is no need for "true" personal identity to be established - since the only entity that can decrypt the PGP encrypted verification email is the owner of the associated private key. I've drawn a very rough diagram for you... http://s26.postimg.org/daz5u1izd/replacement_CA.png http://s26.postimg.org/daz5u1izd/replacement_CA.png

peterwwillis 12y ago
No, I understand PKI. What you've created is less secure than what we have now. If computer A wants to connect securely to computer B, and it doesn't want its connection to be MITM'd, computer A trusts a 3rd party (computer C) to tell it that computer B is really computer B and not a fake. If you take over the DNS system (which is your version of computer C in my example) you get to write anything to computer A and it will believe it. The whole idea behind a MITM is that an attacker controls communication between A and B, and ideally also controls communication between A and C. Just controlling the network isn't enough to subvert the connection, though, because an attacker would need to control one of A, B, or C. If you are the NSA, and you write up a very nice National Security Letter and go to computer C and say "make a fake DNS record for me, because terrorism," you now get to write blank checks for yourself and computers A and B have effectively no idea that their connection is now subject to MITM. Specifically to exploit your system all you'd need to do is create a fake A record pointing to computer D, and a fake public key record which matches the PGP key and SSL cert of computer D. If you weren't using DNSSEC you could do this on a regular open wireless network with no extra hacking needed. If you are using DNSSEC (and a mandatory validating stub resolver, which Windows doesn't ship with) you'd need to take over the root DNS servers or the registrar which feeds records to the .com. root DNS servers. But the NSA can do all that. Probably others too. So, again, it's the exact same state we're in with the CAs, with the exception that DNS would be less secure because the client (computer A) doesn't have any public keys/ca certs stored on it to verify the DNS servers or domains against.
- me1010 12y ago
  In order to create a fake record, you would need to replace the PGP ID on the registrar's record. In order to that, you'd need to intercept and decrypt a PGP encrypted email. In order to do that you need to be in possession of the private key and have the passphrase. An attacker could steal the private key from the domain owner's computer [not the server] and install a keylogger to get the passphrase ... or an attacker could produce a private key from a public key... good luck with that one... The system I've laid out would be significantly more secure and less spoof-able than the current system. Further, DNSSEC becomes entirely unnecessary... Also, it is entirely possible to create a registrar which would store all user record data in an encrypted store which could also be encrypted using a domain owner provided public key... if this were added to the architecture, no government entity could modify anything regarding a domain - except replacement of the entire record. Of course, since the entire system current and any possible future Internet relies upon computers and networks that are explicitly not under the control of the content provider - any government can at any time break the system... This is always going to be true of any and every system of wide networks. EDIT: Computer A and B need a third entity C to validate A to B and B to A. True... However, this does not need to be a computer -- it could very well be a cryptographically generated unique ID... In my example "C" is the PGP ID. However, it could be any cryptographic item that is tied to the domain record and only modifiable using the private key that generated the unique cryptographic item... for example, it could be a bit coin address.
  - peterwwillis 12y ago
    > Of course, since the entire system current and any possible future Internet relies upon computers and networks that are explicitly not under the control of the content provider - any government can at any time break the system... This is always going to be true of any and every system of wide networks. This is the entire reason we are trying to get away from CAs! What we have works perfectly fine. The only reason anyone wants to get away from it is to prevent state actors from overriding a CA's authority. If you want to just reinvent the wheel with the DNS system, use RFC 6698.
    - 12y ago

by me1010 12y ago

peterwwillis 12y ago

No, I understand PKI. What you've created is less secure than what we have now. If computer A wants to connect securely to computer B, and it doesn't want its connection to be MITM'd, computer A trusts a 3rd party (computer C) to tell it that computer B is really computer B and not a fake. If you take over the DNS system (which is your version of computer C in my example) you get to write anything to computer A and it will believe it. The whole idea behind a MITM is that an attacker controls communication between A and B, and ideally also controls communication between A and C. Just controlling the network isn't enough to subvert the connection, though, because an attacker would need to control one of A, B, or C. If you are the NSA, and you write up a very nice National Security Letter and go to computer C and say "make a fake DNS record for me, because terrorism," you now get to write blank checks for yourself and computers A and B have effectively no idea that their connection is now subject to MITM. Specifically to exploit your system all you'd need to do is create a fake A record pointing to computer D, and a fake public key record which matches the PGP key and SSL cert of computer D. If you weren't using DNSSEC you could do this on a regular open wireless network with no extra hacking needed. If you are using DNSSEC (and a mandatory validating stub resolver, which Windows doesn't ship with) you'd need to take over the root DNS servers or the registrar which feeds records to the .com. root DNS servers. But the NSA can do all that. Probably others too. So, again, it's the exact same state we're in with the CAs, with the exception that DNS would be less secure because the client (computer A) doesn't have any public keys/ca certs stored on it to verify the DNS servers or domains against.

me1010 12y ago
In order to create a fake record, you would need to replace the PGP ID on the registrar's record. In order to that, you'd need to intercept and decrypt a PGP encrypted email. In order to do that you need to be in possession of the private key and have the passphrase. An attacker could steal the private key from the domain owner's computer [not the server] and install a keylogger to get the passphrase ... or an attacker could produce a private key from a public key... good luck with that one... The system I've laid out would be significantly more secure and less spoof-able than the current system. Further, DNSSEC becomes entirely unnecessary... Also, it is entirely possible to create a registrar which would store all user record data in an encrypted store which could also be encrypted using a domain owner provided public key... if this were added to the architecture, no government entity could modify anything regarding a domain - except replacement of the entire record. Of course, since the entire system current and any possible future Internet relies upon computers and networks that are explicitly not under the control of the content provider - any government can at any time break the system... This is always going to be true of any and every system of wide networks. EDIT: Computer A and B need a third entity C to validate A to B and B to A. True... However, this does not need to be a computer -- it could very well be a cryptographically generated unique ID... In my example "C" is the PGP ID. However, it could be any cryptographic item that is tied to the domain record and only modifiable using the private key that generated the unique cryptographic item... for example, it could be a bit coin address.
- peterwwillis 12y ago
  > Of course, since the entire system current and any possible future Internet relies upon computers and networks that are explicitly not under the control of the content provider - any government can at any time break the system... This is always going to be true of any and every system of wide networks. This is the entire reason we are trying to get away from CAs! What we have works perfectly fine. The only reason anyone wants to get away from it is to prevent state actors from overriding a CA's authority. If you want to just reinvent the wheel with the DNS system, use RFC 6698.
  - 12y ago