On Thu May 22 2008, Mike McGrath wrote: > Client tries to ssh to Server A > > Server A generates a random number, encrypts it with pub, sends it to the > client > > The client decrypts this number with private key and sends it back to A. > > Bam! Shell. The public key authentication does not work this way. > The guys in #openssh are saying this isn't possible but I wasn't convinced > with their reason (basically that server B doesn't have server A's > host keys). Can someone else explain why the above isn't possible? To authenticate, the client needs to sign a session identifier (and some other information) with his private key and send the signature to the server. The session identifier is a hash of several data that includes the host key. Regards, Till
Description: This is a digitally signed message part.