In SSH, what is the difference between host key and public key.
Public key I believe that is part of private/public key pair, so, that anything sent by server(encrypted using private) can be decrypted by client using public key and anything sent after encrypting with public key can only be decrypted by server's private key.
In SSH, server sends a Host key and client is supposed to know the Hash of host key before hand or cache it in a local store after client receives the key for the first time, which assures the authenticity of host.
My question is: Is my understanding of difference between the two is correct? If yes, then once, a machine gets a host key of a server upon connecting to it, can it not copy the host key and forge its identity as server whose host key it copied or there is some relation between private key and host key as it is between public and private key?