For questions relating to protocols for distributing public keys, and / or establishing session keys with another party. Examples of key exchange protocols include Diffie-Hellman and IKE.

learn more… | top users | synonyms

3
votes
1answer
70 views

OpenSSL's EVP functions, more specifically EVP_SealInit

Reference: https://wiki.openssl.org/index.php/Manual:EVP_SealInit%283%29 I want to securely share a symmetrical key between two endpoints using OpenSSL's EVP interface. Transferring the encrypted ...
2
votes
1answer
47 views

Can a user verify the quality/safety of pregenerated SSH moduli parameters?

Many tutorials about how to mitigate the Logjam recommend regenerating Diffie-Hellman moduli. This is a resource intensive operation, especially for high-bit groups. This made me think if it made ...
3
votes
0answers
161 views

Main difference between Yahalom and Needham-Schroeder key exchange protocols

I am just wondering what is the main difference between the Yahalom and Needham-Schroeder key exchange protocols? Which protocol uses less computational power?
2
votes
0answers
47 views

How rf remotes for “cloning” rolling code find matching codes?

I've been tinkering with a rf (garage door) remote control that has a scanner mode (google JMA SR-48 for details). This mode works for Mutancode and Erreka which I assume would be similar to KeeLoq. ...
2
votes
0answers
46 views

Can SRP be implemented using libsodium

I am using libsodium for cryptography and I want to use SRP for key exchange. The wikipedia page lists a python example, but I am not sure if and how I could convert this to libsodium function calls. ...
1
vote
0answers
60 views

Diffie Hellman Key Exchange in a messaging application

I'm currently a student that is trying to develop a messaging application on android using java that will implement diffie hellman key exchange in order to ensure that they both will be able to ...
1
vote
0answers
26 views

key hierarchy management and master key

Now, I have this equation, {{K_ab}K_bs}K_as. K_ab is encrypted by K_bs then whole packet is encrypted by K_as I think the key structure is K_as is the master key, K_bs is under K_as and K_ab is the ...
1
vote
0answers
59 views

Key Hierarchy and key Encryption

If i have two 56-bit DES keys, and I use these two key to encrypt a 256-bit AES key. Like this: K_AT encrypts K_BT and K_BT encrypts K What is the effective security of key K? Is it 2 X 56 Bits?
1
vote
0answers
38 views

Migration problem between different machines using TrouSerS TPM library

My question coincides with the question posted by Maximiliano Ezequiel. Below is a question. I could make migration process work in one single machine. I can: Export SRK public key. ...
1
vote
0answers
63 views

how IKE (Internet Key Exchange) protocol reacts to the replay attack?

I mean how IKE in any mode (quick,aggressive, main) responds to an attacker that tries to replay one or more messages?
1
vote
0answers
117 views

Verifying the owner of a signing key

I'm using elliptic curve cryptography (curve25519 and ed25519) for key exchange and signing. The signing and key exchange keypairs are independent. I need two users to be able to verify each other's ...
1
vote
0answers
283 views

SSH using pre-existing session (symmetric) keys

Is there at present a way to open a SSH connection using pre-existing symmetric session keys? In other words, if I create a list of symmetric keys can I send that list to the recipient on a CD or USB ...
1
vote
0answers
256 views

Does Diffie-Hellmann (DH) key exchange protocol lower Off-The-Record protocol (OTR) security level?

Off-the-Record protocol employes Diffie-Hellman key exchange protocol (DH). DH protocol does not provide authentication of the communicating parties and, according to many sources, is vulnerable to ...
1
vote
0answers
61 views

Any Suggestion Exchanging shared key between process via port in untrusted machine (infected my malware)?

I am trying to get shared key between Firefox extension and a java program running in same machine. I am communicating both application via socket. My assumption is that malware is running in ...
0
votes
0answers
20 views

Key Distribution Center Key Protocol Analysis

http://i68.tinypic.com/fwu92v.png As shown in the image, why is Circle 1 to be B and Circle 2 to be A? Why is not the opposite, that is, Circle 1 to be A and Circle 2 to be B? like this picture ...
0
votes
0answers
115 views

Secure Handshake and register for Auth

The registration The Start - pre-authentication Let's assume there are Alice and Bob. They know each others public keys and each of them generates a random string - Bob's Bobkey and Alice's Alicekey....
0
votes
0answers
38 views

Preventing a key from being found by analysis

Lets say Alice wants to send an encrypted message to Bob. They both know a secret key. Alice uses the key to encrypt the message and Bob uses the key to decrypt the message. Now, if the handshake ...
0
votes
0answers
38 views

Distribution of key by server

I have read that in asymmetric cryptography, a system admin can generate key pairs on the server. After that, the users will be given the generated key pairs and this is an efficient way of doing this ...