User's Manual

FILE AUTHENTICATION
Introduction to File Authentication
76 VX 675 REFERENCE GUIDE
Special Files Used
in the File
Authentication
Process
The following specially formatted files support the file authentication process:
• A digital certificate is a digital public document used to verify the signature of
a file.
• A digital signature is a piece of information based on both the file and the
signer’s private cryptographic key. The file sender digitally signs the file using
a private key. The file receiver uses a digital certificate to verify the sender’s
digital signature.
• Signer private keys (*.key files) are securely conveyed to clients on smart
cards. The secret passwords required by clients to generate signature files,
using signer private keys, are sent as PINs over a separate channel such as
registered mail or encrypted e-mail.
Some files, such as private key files, are encrypted and password protected for
data security. Others, such as digital certificates and signature files, do not need
to be kept secure to safeguard the overall security of VeriShield Retain.
Within the VeriShield File Signing Tool tool, you can recognize the special file
types that support the file authentication process by the filename extensions listed
in Table 7.
All digital certificates are generated and managed by the VeriFone CA, and are
distributed on request to VX 675 clients—either internally within VeriFone or
externally to sponsors.
All certificates issued by the VeriFone CA for the VX 675 platform, and for any
VeriFone platform with the VeriShield Retain security architecture, are
hierarchically related. That is, a lower-level certificate can only be authenticated
under the authority of a higher-level certificate.
The security of the highest-level certificate, called the platform root certificate, is
tightly controlled by VeriFone.
Certificates Contain Keys That Authenticate Signature Files
• Sponsor certificate: Certifies a client’s sponsorship of the terminal. It does not,
however, convey the right to sign and authenticate files. To add flexibility to
the business relationships that are logically secured under the file
authentication process, a second type of certificate is usually required to sign
files.
Table 7 VeriShield File Signing Tool Filename Extensions
File Type Extension
Signature *.p7s
Private key *.key
Digital certificate *.crt