> To the best of my knowledge, the encryption keys and signing keys are the
> same.

Huh. No. You have private keys and public keys. Public keys are distributed
and can be used to encrypt data that only the private key can decrypt.
Private keys can be used to sign data (actually it encrypts a hash value of
the data such as MD5 or SHA1) and this signature can be verified (decrypted)
by the public key. This is essentially true of all "public key"
cryptography.

> i.e. You would negotiate a session key that would be used to symmetrically
> encrypt the data sent. The fact that the recipient can decrypt it implies
> that the data is authentic, since only the two parties would be privy to
the
> session key.
>
> It is possible to use a "null" algorithm, I think, that simply does no
> encryption. This allows the client to be sure that they are talking to the
> server, and potentially allows the server to know that it is talking to
the
> client (if you are using client certs), but reduces the overhead of
actually
> encrypting the data.

>From Apache:

#SSLCipherSuite
ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP:+eNULL

notice the last one.

> I'm not sure if this has any guarantees about the integrity of the data
> anymore, though.

Nope, none, it's cleartext, which make's man in the middle or injection
possible.

> I'm really not sure what you are asking though. SSL is inherently
asymmetric
> in the key negotiation phase, and symmetric in the encryption phase
>
> Hope this helped.
>
> Rogan


> > Just a quick question
> >
> > say I wish to setup an SSL link between a client and a server
> > - but I just want to perform digital signing from the client
> > to the server,
> > are these two functions (i.e. the setting up of the SSL
> > tunnel, and the signing mechanism) considered totally
> > separate -i.e. is the tunnel setup completely separately and
> > using different key/certificate systems than the digital
> > signing keys and certs?

SSL is an encryption method that uses X.509 certificates. X.509 certificates
can be signed, typically this is done by a "certificate authority". Your
browser has the public keys of the certificate authority, thus allowing it
to verify the certificate authority's signature on the X.509 certificate
presented to you from the webserver, thus allowing you to decide on some
level of trust (usually complete).

> > What I am considering is to use a phone to link to an SSL
> > enabled server - will the phone download the cert of just a
> > hashed algorithm from the server. The Netscape site is next
> > to useless - which is strange since they have developed the protocol.
> >
> > Does anyone know a useful place to find such information on
> > Symmetric SSL etc.

Symetric encryption requires some sort of preshared secret, a password, a
long string of text, etc. Hence it isn't terribly useful outside of password
authentication where you have a preshared secret of sorts (the password).

> > Any ideas ???

Kurt Seifried, [EMAIL PROTECTED]
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http://seifried.org/security/
http://www.idefense.com/digest.html



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