7 ms·
Curious to hear from someone working in a company who says things but not show it's true. In fact, if i say i am rich, tall, blond with a famous sense of humour
by Discretio 14y ago
Curious to hear from someone working in a company who says things but not show it's true.
In fact, if i say i am rich, tall, blond with a famous sense of humour, you are ready to believe me, but if i don't say anything but i prove it, you refuse to believe me... strange.
Discretio doesn't say anything of this kind but show the entire client software source code. Do the same please.
- StavrosK 14y agoSo how do you protect against MITMs?
- Discretio 14y agoYou still ask for words, i still ask for your source code...
- StavrosK 14y agoI don't own the company, thus I can't give you the code. You can give me an explanation, but won't. Why?
- vadiml 14y agoBasically the client connects to SIP server using ssl connection authenticated on both sides. When placing calls the clients A and B are negotiating SRTP session key using DH key exchange. It is done over SIP (and not over RTP channel as in ZRTP). Each client upon registration generates public/private key pair and submits a CSR to the registration service which signs it and stores the public key (which is later used to authenticate the above mentionned ssl connections) in the SIP server's DB... The server has no access to the client's private key nor to the SRTP session key
- StavrosK 14y agoHmm, it sounds resistant to random MITM but the server can still listen in on the calls if it wants, by MITMing the clients itself...
- vadiml 14y agoYes, with the cooperation from CA the MITM is still possible. We however will provide server code to especially paranoid clients so they can build and run the software on their own machines... This way they can have garanties against certificate tampering. And we're working on an alternative solution when even cooperating CA will not allow MITM...
- StavrosK 14y agoThat sounds very good, good luck! Why not use ZRTP, though?
- vadiml 14y agoWell, this tech is derived from the project which was designed to meet specs of one of our clients. We did propose ZRTP during design phase, to the client but they security analysts decided against it. They affirm that given the state the current state of art in speech recognition and synthesis ZRTP can be vulnerable on impersonation during short code validation phase for the attacker with sufficient resources. I'm personally doubtful, but one thing i'm sure about, is that this client security experts have access to info and resources which are not available to me.
- StavrosK 14y agoThat sounds reasonable, thanks for the explanation.