OSF DCE Application Development Guide--Core Components

DCE Security Service
2. Since the request for a ticket to the Privilege Service is encrypted under the
conversation key associated with the TGT, the Authentication Service believes
that the identity of the user is authentic; that is, no other principal could have sent
a message so encrypted because no other principal knows the secret key under
which the Authentication Service encrypted that conversation key. Since the user
has proved to the Authentication Service knowledge of the key, the
Authentication Service allows the user to talk to the Privilege Service, and so
prepares a ticket to that service. This ticket contains the identity of the user (and a
second conversation key) encrypted under the secret key of the Privilege Service.
Like the TGT envelope, the envelope containing the ticket to the Privilege
Service also contains the second conversation key, for use in conversing with the
Privilege Service, and is encrypted with the first conversation key.
Note: Beginning with Figure 23-4, the illustrations do not show the
Authentication Service decrypting and reencrypting requests for
tickets, since it knows all of the keys.
3. Upon receipt of the envelope containing the ticket to the Privilege Service, the
Security client runtime decrypts the envelope using the first conversation key,
and in the process learns the second conversation key. The client RPC runtime
sends the Privilege Service ticket to the Privilege Service.
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