Oracle Secure Backup 10.3, Руководство по установке и настройке

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Host Authentication and Communication
6-10 Oracle Secure Backup Installation and Configuration Guide
creates a digital signature by submitting the message as input to a cryptographic hash
function and then encrypting the output hash with a private key.
The receiving host authenticates the digital signature by decrypting it with the sending
host's public key. Afterwards, the receiving host decrypts the encrypted message with
its private key, inputs the decrypted message to the same hash function used to create
the signature, and then compares the output hash to the decrypted signature. If the
two hashes match, then the message has not been tampered with.
Figure 6–3 illustrates how host B can encrypt and sign a message to host A, which can
in turn decrypt the message and verify the signature.
Figure 6–3 Using Public and Private Keys to Encrypt and Sign Messages
Authenticated SSL Connections
For hosts to securely exchange control messages and backup data within the domain,
they must first authenticate themselves to one another. Host connections are always
two-way authenticated except for the initial host invitation to join a domain and
communication with
Network Data Management Protocol (NDMP) servers.
In two-way authentication, the hosts participate in a handshake process whereby they
mutually decide on a cipher suite to use, exchange identity certificates, and validate
that each other's
identity certificate has been issued by a trusted Certification
Authority (CA) . At the end of this process, a secure and trusted communication
channel is established for the exchange of data.
The use of identity certificates and Secure Sockets Layer (SSL) prevents outside
attackers from impersonating a client in the administrative domain and accessing
backup data. For example, an outside attacker could not run an application on a
non-domain host that sends messages to domain hosts that claim origin from a host
within the domain.
Certification Authority
The service daemon (observiced) on the administrative server is the root Certification
Authority (CA) of the administrative domain . The primary task of the CA is to issue
and sign an identity certificate for each host in the administrative domain. The CA's
signing certificate , which it issues to itself and then signs, gives the CA the authority
to sign identity certificates for hosts in the domain. The relationship of trust requires
that all hosts in the administrative domain can trust certificates issued by the CA.
Each host stores its own identity certificate and a trusted certificate (or set of
certificates) that establishes a chain of trust to the CA. Like other hosts in the domain,
the CA stores its identity certificate. The CA also maintains a signing certificate that
authorizes the CA to sign the identity certificates for the other hosts in the domain.
Verify
Signature
Message
From
B to A
Public Key
Host B
Decrypt
Private Key
Host A
Sign
Message
From
B to A
Private Key
Host B
Ecrypt
Public Key
Host A
Host A Host B