摘要:
Computer systems and environments implemented herein permit a local machine increased participation in authorizing access to protected content. An operating system attests to a computing environment at a corresponding computer system. If the computing environment is one permitted to access protected content, the operating system is permitted to regulate further (e.g., application) access to protected content in accordance with a procreation policy. As such, authorization decisions are partially distributed, easing the resource burden on a content protection server. Accordingly, this computing environment can facilitate more robust and efficient authorization decisions when access to protected content is requested.
摘要:
Systems and methods for enabling trusted software to monitor and control USB traffic associated with a security extension of a host controller and devices in a USB topology is disclosed. A host controller proxy receives USB-related data from a host controller driver, determines whether the data is of a security interest, and if so, sends the data to a driver for a security extension executing in the trusted execution environment. Likewise, after software executing in the trusted execution environment evaluates and appropriately addresses data sent by the HCD proxy or data retrieved from a hardware security extension, the HCD proxy receives data from the trusted execution environment for further dissemination.
摘要:
Protecting computer systems from attacks that attempt to change USB topology and for ensuring that the system's information regarding USB topology is accurate is disclosed. A software model is defined that, together with secure USB hardware, provides an ability to define policies using which USB traffic can be properly monitored and controlled. The implemented policy provides control over USB commands through a combination of software evaluation and hardware programming. Legitimate commands are evaluated and “allowed” to be sent to a USB device by a host controller. Illegitimate commands are evaluated and blocked. Additionally, the USB topology is audited to verify that the system's topology map matches the actual USB topology.
摘要:
The present invention extends to methods, systems, and computer program products for protecting content. Embodiments of the invention permit a local machine increased participation in authorizing access to protected content. An operating system attests to a computing environment at a corresponding computer system. If the computing environment is one permitted to access protected content, the operating system is permitted to regulate further (e.g., application) access to protected content in accordance with a procreation policy. As such, authorization decisions are partially distributed, easing the resource burden on a content protection server. Accordingly, embodiments of the invention can facilitate more robust and efficient authorization decisions when access to protected content is requested.
摘要:
A system and method for performing secure peer-to-peer device communications on an I/O bus, such as a PCI bus, a Fiber Channel bus, an IEEE, 1394 bus or a Universal Serial Bus. The system includes a plurality of intelligent I/O devices, such as intelligent storage devices and/or controllers, communications devices, video devices and audio devices. The I/O devices perform peer-to-peer message and data transfers, thereby bypassing the operating system running on the computer's CPU. The intelligent I/O devices encrypt messages and data before transmitting them on the I/O bus and conversely decrypt the messages and data upon reception. The encryption provides secrecy and/or authentication of the sender. The devices use keys or passwords to encrypt/decrypt the data. The keys are stored in non-volatile memory in the devices and are distributed to the devices by the system BIOS at initialization time. The devices perform access authorization validation using rule sets also distributed by the BIOS at initialization time. The rule sets specify which I/O operations are valid for a peer I/O device to request of a respective I/O device based, preferably, upon the device class/subclasses of the requesting device. In another embodiment, one of the intelligent I/O devices may be a communications device which serves as a firewall for the I/O bus. In this embodiment, the rule set further includes identification information of the remote machines/devices.
摘要:
A computer system including a serial bus host controller and host controller driver. The host controller driver providing data structures for the host controller to operate on. The data structures having a linking mechanism for processing lists of descriptors, and alternate buffer configurations for receiving data from the serial bus devices.
摘要:
A method and apparatus of synchronizing a serial bus data rate to a serial bus function data rate to eliminate the build up of overruns or underruns of data. A response is provided to a start of frame packet. The response packet contains a response code for indicating a modification to the serial bus frame counter. Thereby, slight variations in data rates can be eliminated by adjusting the serial bus data rate instead of the serial bus function data rate.
摘要:
A serial bus host controller arbiter which organizes data transfer events into three categories, periodic data transfers, which are usually isochronous transfers; aperiodic transfers, which usually are asynchronous transfers; and control transfers. The arbiter fundamentally operates on a periodic basis. At the beginning of each period, the arbiter preferably alternates between periodic transfers and control transfers. When all of the periodic transfers have been completed, the arbiter then provides access to the various asynchronous transfers which are scheduled to occur, alternating with any remaining control transfers. The arbiter gives preference to the periodic events, and if any time within the period is available, which is referred to as the free time, control events are interleaved with periodic events until no free time remains or all are completed. Any remaining time in the period is used cycling through the aperiodic transfers. The arbiter of the preferred embodiment keeps a running total of free time during each period to determine if additional control or aperiodic transfers can occur.
摘要:
A redundancy scheme is described for replacing defective main memory cells in a dynamic RAM with spare memory cells. The spare cells are arranged in groups of spare rows and spare columns of memory cells such that a plurality of groups of spare rows and columns of cells are substituted for defective main rows and columns of cells so as to repair relatively large defects which impair adjacent rows and columns of main memory cells. In the preferred embodiment, the RAM includes a plurality of address buffers, each of which receives an incoming row address bit and then an incoming column address bit for sequentially outputting row and column address data. Associated with each buffer is a store for a defective row address, a store for a defective column address, and a comparator. The stores retain defective memory cell addresses which the comparator sequentially compares against the address data sequentially output by the buffer. When the comparator senses a match, a control signal is generated to initiate substitution of spare memory cells for the defective main memory cells.
摘要:
The invention overcomes the deficiencies of the art by providing methods for breeding soybean plants containing genomic regions associated with the pubescence alleles, T and Td, associated with increased grain yield. In addition, the invention provides the locus for Td. Moreover, the invention includes germplasm and the use of germplasm containing genomic regions conferring increased yield for introgression into elite germplasm in a breeding program. Moreover, the invention provides methods of purifying soybean breeding lines for such traits as flower color and pubescence color at early stages, such as seed. The invention also provides derivatives, and plant parts of these plants and uses thereof.