Code authentication upon bootup for cable modems

An apparatus (50) for communicating new code to a plurality of electronic devices (52a-n) via a network (53) comprising:

• a server (54) stored a current version of code to be downloaded to the plurality of electronic devices (52a-n);
• a memory (51a-n) disposed in each of the plurality of electronic devices (52a-n) to store code having an RSA-SHA-1 based signature and related authenticated attributes stored at an end of the code file;
• and
• a processor (55a-n) disposed in each of the plurality of electronic devices (52a-n) communicating with the server (54), said processor (55a-n) being coupled to the memory (51a-n) and validating the code file during each reboot operation to confirm that the signature in a header equals the authenticated attributes signed by a private key that created the RSA-SHA-1 based signature.

A method (20) for authenticating code in a device comprising:

• calculating (21) an on-the-fly SHA-1 message digest over a stored Code Header and the Code Image;
• comparing (22) a new message digest with a message digest that was stored;
• if the new message digest is not the same as the stored message digest, declaring (24) the image to be invalid and sending (25) a syslog message to a system operator informing the system operator of a tampered image and shutting down the device;
• and
• if the new message digest is the same as the stored message digest, then:
• calling (27) an RSA Signature Verification function to confirm that a signature equals signed Authenticated Attributes;
• if the signature is valid, executing (29) the code normally;
• and
• if the signature is not valid, sending (25) sends a syslog message to the system operator informing the system operator of a tampered image and shutting the device down.