摘要:
Systems and methods are provided for maintaining and updating a secure boot process on a computer with a trusted platform module (TPM). A boot process may be maintained by inspecting a log of TPM activity, determining data that prevented a secret to unseal, and returning the data to an original state. In situations where this type of recovery is not workable, techniques for authenticating a user may be used, allowing the authenticated user to bypass the security features of the boot process and reseal the boot secrets to platform configuration register (PCR) values that may have changed. Finally, a secure boot process may be upgraded by migrating TPM sealed secrets to a temporary storage location, updating one or more aspects of a secure boot process, and resealing the secrets to the resulting new platform configuration. Other advantages and features of the invention are described below.
摘要:
Systems and methods are provided for maintaining and updating a secure boot process on a computer with a trusted platform module (TPM). A boot process may be maintained by inspecting a log of TPM activity, determining data that prevented a secret to unseal, and returning the data to an original state. In situations where this type of recovery is not workable, techniques for authenticating a user may be used, allowing the authenticated user to bypass the security features of the boot process and reseal the boot secrets to platform configuration register (PCR) values that may have changed. Finally, a secure boot process may be upgraded by migrating TPM sealed secrets to a temporary storage location, updating one or more aspects of a secure boot process, and resealing the secrets to the resulting new platform configuration. Other advantages and features of the invention are described below.
摘要:
Systems and methods for controlling access to data on a computer with a secure boot process can provide a highly efficient mechanism for preventing future access to encrypted digital resources. This may be advantageous in a range of scenarios, for example where a computer is sold and assurance is desired that no stray private data remains on the hard disk. Data resources, for example all data associated with one or more particular hard disk partitions, may be encrypted. The decryption key may be available through a secure boot process. By erasing, altering, or otherwise disabling a secret, such as a decryption key or a process that obtains a decryption key, the data formerly accessible using such secret becomes inaccessible.
摘要:
Access to a storage device, such as a disk, is controlled by performing a disk operation using a single cryptographic engine. Keys associated with each layer of a layered structure associated with controlling access to the storage device are combined. The resultant of this combination is used as the key to the cryptographic engine. Data to be retrieved from and written to the storage device are operated on by the cryptographic engine utilizing the combined key. Keys are combined by combining functions associated with layers of the layered structure. A combining function can include an exclusive or function, a cryptographic hash function, or a combination thereof.
摘要:
Access to a storage device, such as a disk, is controlled by performing a disk operation using a single cryptographic engine. Keys associated with each layer of a layered structure associated with controlling access to the storage device are combined. The resultant of this combination is used as the key to the cryptographic engine. Data to be retrieved from and written to the storage device are operated on by the cryptographic engine utilizing the combined key. Keys are combined by combining functions associated with layers of the layered structure. A combining function can include an exclusive or function, a cryptographic hash function, or a combination thereof.
摘要:
A mechanism for protected operating system boot that prevents rogue components from being loaded with the operating system, and thus prevents divulgence of the system key under inappropriate circumstances. After a portion of the machine startup procedure has occurred, the operating system loader is run, the loader is validated, and a correct machine state is either verified to exist and/or created. Once the loader has been verified to be a legitimate loader, and the machine state under which it is running is verified to be correct, the loader's future behavior is known to protect against the loading of rogue components that could cause divulgence of the system key. With the loader's behavior being known to be safe for the system key, the validator may unseal the system key and provides it to the loader.
摘要:
Attachments or other documents can be transmitted to a sandbox environment where they can be concurrently opened for remote preview from an endpoint and scanned for possible malware. A gateway or other intermediate network element may enforce this process by replacing attachments, e.g., in incoming electronic mail communications, with links to a document preview hosted in the sandbox environment.
摘要:
Prevention of unpermitted use of enabling bits is achieved by sealing the enabling bits to an environment in such a way that the bits can only be unsealed by or from the environment, and by using an isolation mechanism to isolate the environment from other environments on the machine on which the environment operates. The environment is trusted not to use the enabling bits except in accordance with a set of rules governing the bits. The enabling bits may be a decryption key for DRM-protected content, and the rules may be a license governing the use of that content. Trust that the enabling bits will not be misused is established by trusting the environment not to use the enabling bits contrary to the rules, trusting the isolation mechanism to isolate the environment, and trusting the unsealing mechanism only to unseal the bits for the environment.
摘要:
The various embodiments described below are directed to providing authenticated and confidential messaging from software executing on a host (e.g. a secure software application or security kernel) to and from I/O devices operating on a USB bus. The embodiments can protect against attacks that are levied by software executing on a host computer. In some embodiments, a secure functional component or module is provided and can use encryption techniques to provide protection against observation and manipulation of USB data. In other embodiments, USB data can be protected through techniques that do not utilized (or are not required to utilize) encryption techniques. In accordance with these embodiments, USB devices can be designated as “secure” and, hence, data sent over the USB to and from such designated devices can be provided into protected memory. Memory indirection techniques can be utilized to ensure that data to and from secure devices is protected.
摘要:
A resource is obtained from a resource provider (RP) for a resource requester (RR) operating on a computing device. The RR has an identity descriptor (id) associated therewith, where the id including security-related information specifying an environment in which the RR operates. A code identity (code-ID) is calculated corresponding to and based on the loaded RR and loaded id. The RP verifies that the calculated code-ID in a request for the resource matches one of one or more valid code-IDs for the identified RR to conclude that the RR and id can be trusted, and the RP responds to the forwarded request by providing the requested resource to the RR.