Apparatus and method for managing digital rights through hooking a kernel native API

An apparatus for managing digital rights, the apparatus comprising:

• a computer hardware processor executing application modules, the application modules comprising:
• an agent unit configured to manage application programs to which DRM is to be applied and a right to contents processed by the application programs to which DRM is to be applied and encrypt or decrypt the contents processed by the application programs to which DRM is to be applied;
• a rights management unit configured to authenticate a user and manage a user right to the contents processed by the application programs to which DRM is to be applied;
• and
• a kernel API hooking unit configured to monitor input/output of a file through hooking of kernel native APIs, request the rights management unit to verify a user right to contents to be processed when the contents are detected as being processed by the application programs to which DRM is to be applied, and request the agent unit to encrypt or decrypt the contents to be processed in response to verifying the user right to the contents to be processed,
• wherein the agent unit, the rights management unit, and the kernel API hooking unit are driven for each application program to which DRM is to be applied, and
• wherein the kernel API hooking unit comprises:
• a rights control unit configured to request the agent unit and the rights management unit to verify the user right to the contents corresponding to file input/output events and outputting the verification result;
• an encryption/decryption control unit configured to hook the kernel native APIs to detect the file input/output events, request the rights management unit to verify the user right to the contents to be processed corresponding to the file input/output events, and deliver the contents to be processed to the agent unit to direct encryption or decryption on the basis of the verification result;
• and
• a cache processing unit configured to receive previously encrypted or decrypted contents from the encryption/decryption control unit and store the contents in a built-in cache memory, thereby preventing an opened document from being encrypted or decrypted repeatedly, and in response to an inquiry whether the contents to be processed have been encrypted or decrypted being input from the encryption/decryption control unit, is configured to search the cache memory and return the contents or output a notification that the contents has been not decrypted.

An apparatus for managing digital rights, the apparatus comprising:

• a computer hardware processor executing application modules, the application modules comprising:
• an agent unit configured to manage application programs to which DRM is to be applied and a right to contents processed by the application programs to which DRM is to be applied and encrypt or decrypt the contents processed by the application programs to which DRM is to be applied;
• a rights management unit configured to authenticate a user and manage a user right to the contents processed by the application programs to which DRM is to be applied;
• and
• a kernel API hooking unit configured to monitor input/output of a file through hooking of kernel native APIs, request the rights management unit to verify a user right to contents to be processed when the contents are detected as being processed by the application programs to which DRM is to be applied, and request the agent unit to encrypt or decrypt the contents to be processed in response to verifying the user right to the contents to be processed,
• wherein the agent unit, the rights management unit, and the kernel API hooking unit are driven for each application program to which DRM is to be applied, and
• wherein the kernel API hooking unit comprises:
• a rights control unit configured to hook the kernel native APIs to detect file input/output events, request the agent unit and the rights management unit to verify the user right to the contents to be processed corresponding to the detected file input/output events, and output the verification result;
• an encryption/decryption control unit configured to deliver the contents to be processed to the agent unit on the basis of the verification result to direct encryption or decryption;
• and
• a cache processing unit configured to receive previously encrypted or decrypted contents from the encryption/decryption control unit and store the contents in a built-in cache memory, thereby preventing an opened document from being encrypted or decrypted repeatedly, and in response to an inquiry whether the contents to be processed have been encrypted or decrypted being input from the encryption/decryption control unit, searches the cache memory and returns the contents or outputs a notification that the contents has been not decrypted.

A method for managing digital rights, the method comprising:

• (a) injecting a DRM engine module into an application program to which DRM is to be applied when the application program to which DRM is to be applied is driven;
• (b) monitoring input/output of a file, using a processor, through hooking a kernel native API, and when a content is detected as being processed by the application program to which DRM is to be applied, verifying, using a processor, a user right to the content to be processed in the application program to which DRM is to be applied;
• (c) selectively encrypting or decrypting the content to be processed when the user right to the content to be processed is verified;
• and
• (d) returning the encrypted or decrypted content to the kernel native API,
• wherein step (a) and step (c) are performed at user level, and step (b) and step (d) are performed at kernel level, and
• wherein step (c) comprises:
• (c1) hooking the kernel native API to detect a file input/output event;
• (c2) verifying, using a processor, the user right to the content to be processed corresponding to the file input/output event, authenticating the user, and managing the user right to the content to be processed in the application program to which DRM is to be applied;
• and
• (c3) encrypting or decrypting the content on the basis of the verification result.