5 ms·

This is a good question. What makes it secure ? "encryption" is not enough. Do you have central servers or is it protocol using P2P ? how do you connect one cli

This is a good question. What makes it secure ? "encryption" is not enough. Do you have central servers or is it protocol using P2P ? how do you connect one client to another ? What kind of encryption ? How are the key generated, can we change them etc...

kragniz 12y ago
The whole protocol is decentralized and peer to peer. Each person in the network has a public and private key. The NaCl library is used to do all of the encryption.
- alex_duf 12y ago
  Cool. Is this direct connection from peer to peer or does the communication bounce from one node to another as a TOR communication would do ? (I'm guessing direct for obvious latency reasons when using audio / video)
  - irungentoo 12y ago
    Direct connection when possible. Connection routed over one TCP node when direct connections are impossible due to NAT issues.
    - sitkack 12y ago
      What if I don't want a direct connection for security/anon reasons?
    - walterbell 12y ago
      Does only the one-time signalling handshake go to a TCP node (NAT hole punching) or does all traffic? Are these TCP nodes similar to Skype "super-peers" - how are they selected? Virtually all consumers are behind NAT devices.
      - irungentoo 12y ago
        The majority of NATs can be hole punched. If you can't hole punch then you will connect to your friend through a couple TCP nodes. They act like relays. TCP nodes are pretty much randomly selected by peers and anyone can host them. Everything is encrypted and TCP nodes are regarded as being possibly hostile so there should not be any security issues.
- eps 12y ago
  Do you have exact crypto spec somewhere? "NaCl library" is not a spec and it's still easy to use/apply it incorrectly.
  - kragniz 12y ago
    Crypto is outlined over here: https://github.com/irungentoo/toxcore/blob/master/docs/updates/Crypto.md https://github.com/irungentoo/toxcore/blob/master/docs/updat...
dredmorbius 12y ago
"Secure" is a lot of things. "Secure against bulk surveillance" is a big push in a lot of areas, it's a button Bruce Schneier and Eben Moglen have been pushing hard for the past year or so. See especially their joint lecture at Columbia Law School in December, 2013, and Schneier's presentation to Stanford Law School in April, 2014 (both are on http://FixYT.com http://FixYT.com). Anonymized persistent IDs associated with physical / persistent IP addresses represents a different level of threat, particularly for those who are engaged in activities for which concern from a APT (advanced persistent threat) such as a state actor, with either legal impunity or significant resources, or both, is a concern. In that case, I'd want to see a system with repudiable identifiers and Onion routing such that endpoints aren't clearly determinable. That said, yours is a crucial question. Related: what are the threat models against which Tox is a response?
- irungentoo 12y ago
  Our threat model is an attacker that wants to read and record the contents of conversations between everyone, they have the ability to modify/add/remove and log any packets. We assume they do not have any access to the actual machines Tox is running on. The main goal of Tox is to make it hard for a global threat to conduct mass surveillance on everyone at the same time without sacrificing performance. If the majority of the people using Tox have "nothing to hide" and use it because it works better than skype, the minority that does need the crypto will be able to use it without being discriminated against.
  - dredmorbius 12y ago
    Thanks, that's a nice and concise statement. NB, a comment by Peter da Silva, who's been doing networking / communications / security stuff for quite a while: "Don't like the callback model in the API, they need a version of tox_wait() that takes a select() fd mask." https://plus.google.com/u/0/104092656004159577193/posts/MDYUCSjcjQd https://plus.google.com/u/0/104092656004159577193/posts/MDYU...

kragniz 12y ago

The whole protocol is decentralized and peer to peer. Each person in the network has a public and private key. The NaCl library is used to do all of the encryption.

alex_duf 12y ago
Cool. Is this direct connection from peer to peer or does the communication bounce from one node to another as a TOR communication would do ? (I'm guessing direct for obvious latency reasons when using audio / video)
- irungentoo 12y ago
  Direct connection when possible. Connection routed over one TCP node when direct connections are impossible due to NAT issues.
  - sitkack 12y ago
    What if I don't want a direct connection for security/anon reasons?
  - walterbell 12y ago
    Does only the one-time signalling handshake go to a TCP node (NAT hole punching) or does all traffic? Are these TCP nodes similar to Skype "super-peers" - how are they selected? Virtually all consumers are behind NAT devices.
    - irungentoo 12y ago
      The majority of NATs can be hole punched. If you can't hole punch then you will connect to your friend through a couple TCP nodes. They act like relays. TCP nodes are pretty much randomly selected by peers and anyone can host them. Everything is encrypted and TCP nodes are regarded as being possibly hostile so there should not be any security issues.
eps 12y ago
Do you have exact crypto spec somewhere? "NaCl library" is not a spec and it's still easy to use/apply it incorrectly.
- kragniz 12y ago
  Crypto is outlined over here: https://github.com/irungentoo/toxcore/blob/master/docs/updates/Crypto.md https://github.com/irungentoo/toxcore/blob/master/docs/updat...

dredmorbius 12y ago

"Secure" is a lot of things. "Secure against bulk surveillance" is a big push in a lot of areas, it's a button Bruce Schneier and Eben Moglen have been pushing hard for the past year or so. See especially their joint lecture at Columbia Law School in December, 2013, and Schneier's presentation to Stanford Law School in April, 2014 (both are on http://FixYT.com http://FixYT.com). Anonymized persistent IDs associated with physical / persistent IP addresses represents a different level of threat, particularly for those who are engaged in activities for which concern from a APT (advanced persistent threat) such as a state actor, with either legal impunity or significant resources, or both, is a concern. In that case, I'd want to see a system with repudiable identifiers and Onion routing such that endpoints aren't clearly determinable. That said, yours is a crucial question. Related: what are the threat models against which Tox is a response?

irungentoo 12y ago
Our threat model is an attacker that wants to read and record the contents of conversations between everyone, they have the ability to modify/add/remove and log any packets. We assume they do not have any access to the actual machines Tox is running on. The main goal of Tox is to make it hard for a global threat to conduct mass surveillance on everyone at the same time without sacrificing performance. If the majority of the people using Tox have "nothing to hide" and use it because it works better than skype, the minority that does need the crypto will be able to use it without being discriminated against.
- dredmorbius 12y ago
  Thanks, that's a nice and concise statement. NB, a comment by Peter da Silva, who's been doing networking / communications / security stuff for quite a while: "Don't like the callback model in the API, they need a version of tox_wait() that takes a select() fd mask." https://plus.google.com/u/0/104092656004159577193/posts/MDYUCSjcjQd https://plus.google.com/u/0/104092656004159577193/posts/MDYU...