Microsoft Technology Licensing, LLC

Carl Melvin Ellison

Stefan Thom

Erik Lee Holt

Shivaram H Mysore

Valerie Kathleen Bays

Niels Thomas Ferguson

Charles W Kaufman

Butler W Lampson

Octavian Tony Ureche

Melissa Wood Dunn

Ravindra Pandya

Paul J Leach

Josh D Benaloh

Tolga Acar

Alex Mark Semenko

Vijay G Bharadwaj

Charles Glenn Jeffries

Sai Vinayak

Brian LaMacchia

John M Parchem

Marc R Barbour

Janet Lynn Schneider

Kristjan Eric Hatlelid

Pieter Kasselman

Michael J Grass

Matthew Charles Setzer

Gaurav Sinha

John R Michener

Kenneth D Ray

Scott Field

Cristian Marius Ilac

Russell Humphries

Manav Mishra

Brandon S Baker

Art Shelest

Elissa E S Murphy

Magnus Bo Gustaf Nyström

Gregory D Hartrell

Jamie Hunter

Philip J Lafornara

Peter Novotney

Arthur Baker

Tore L Sundelin

Dayi Zhou

Mira Belenkiy

Duy Lan Nguyen

Daniel Bakalars Shumow

Andrew Stewart Tucker

Gleb Kholodov

Paul J Lach

Denis Issoupov

Larry Zhu

In the host operating system of a computing device, entropy data is collected based at least in part on each of one or more hardware components of the computing device. An entropy pool is updated based at least in part on the collected entropy data, and data from the entropy pool is provided to a guest operating system running as a virtual machine of the computing device. The guest operating system maintains a guest operating system entropy pool based on the data from the entropy pool provided by the host operating system. The guest operating system accesses the guest operating system entropy pool and uses the guest operating system entropy pool as a basis for generating values including random numbers.

Entropy pools for virtual machines

Systems, methods, and technologies for configuring a conventional smart card and client machine, and for performing a smart card authorization using the configured smart card and client. Further, the combination of methods provides for mutual authentication&#x2014;authentication of the client to the user, and authentication of the user to the client. The authentication methods include presenting a specified token to the user sufficient to authenticate the client to the user and thus protect the user-provided PIN. Security is strengthened by using an integrity key based on approved client system configurations. Security is further strengthened by calculating a PIN' value based on a user-specified PIN and a modifier and using the PIN&#x2032; value for unlocking the smart card.

Integrity protected smart card transaction

The subject disclosure pertains to systems and methods that facilitate managing access control utilizing certificates. The systems and methods described herein are directed to mapping an access policy as expressed in an access control list to a set of certificates. The set of certificates can be used to grant access to resources in the manner described by the ACL. The certificates can be distributed to entities for use in obtaining access to resources. Entities can present certificates to resources as evidence of their right to access the resources. The access logic of the sequential ACL can be transformed or mapped to a set of order independent certificates. In particular, each entry, position of the entry in the list and any preceding entries can be analyzed. The analysis can be used to generate order independent certificates that provide access in accordance with the access policy communicated in the ACL.

Transformation of sequential access control lists utilizing certificates

Each member of a group contributes to and calculates a new shared value. A distributed shared value algorithm is used to reach unanimous agreement on a shared value, such that every group member can use the new shared value as soon as it is changed. The distributed shared value agreement methodology operates without the selection of a leader. Each group member performs the distributed shared value agreement methodology and computes the new shared value using one or more of the contributions from the group members in such a way that no one member coerces the resulting shared value.

Distributed algorithm for changing a shared value

Cryptographic key management techniques are described. In one or more implementations, an access control rule is read that includes a Boolean expression having a plurality of atoms. The cryptographic keys that corresponds each of the plurality of atoms in the access control rule are requested. One or more cryptographic operations are then performed on data using one or more of the cryptographic keys.

Cryptographic key management

Data stored on a storage medium can be referenced by multiple independently addressable active symbolic links, with each active symbolic link representing the data through a different transformation. The active symbolic links can be in the form of file system objects, such as files or directories. A single active symbolic link can reference the data stored in multiple collections, or, conversely, a subset of data from a single collection. Active symbolic links can be automatically created for common data transformations. Searching across active symbolic links referencing encrypted data can be performed by multiple protection-specific search engines, or a single search engine that can generate a protection-level aware search index.

File system active symbolic link

In accordance with one or more aspects, an initial output string is generated by a random number generator. The initial output string is sent to a random number service, and an indication of failure is received from the random number service if the initial output string is the same as a previous initial output string received by the random number service. Operation of the device is ceased in response to the indication of failure. Additionally, entropy estimates for hash values of an entropy source can be generated by an entropy estimation service based on hash values of various entropy source values received by the entropy estimation service. The hash values can be incorporated into an entropy pool of the device, and the entropy estimate of the pool being updated based on the estimated entropy of the entropy source.

Random number generation failure detection and entropy estimation

A set of security claims for a communication channel are obtained, the set of security claims including one or more security claims each identifying a security characteristic of the communication channel. The security claims are stored, as is a digital signature generated over the set of security claims by an entity. The security claims and digital signature are subsequently accessed when a computing device is to transfer data to and/or from the communication channel. The set of security claims is compared to a security policy of the computing device, and the entity that digitally signed the set of security claims is identified. One or more security precautions that the computing device is to use in transferring data to and/or from the communication channel are determined based at least in part on the comparing and the entity that has digitally signed the set of security claims.

Communication channel claim dependent security precautions

A collection of multiple user credentials each associated with one of multiple different users is obtained at a device, and one or more of the multiple user credentials are verified. A determination is made as to whether access to a resource is permitted, by at least comparing the collection of multiple user credentials to a threshold combination of user credentials to be satisfied to access the resource. An indication of whether access to the resource by a requesting user is permitted is returned or provided to another device.

Resource access based on multiple credentials

This document describes tools that constrain a login to a subset of access rights. In one embodiment, the tools generate a constrained password by executing a cryptographic algorithm on a user ID, general password, and one or more desired constraints. The constrained password is used in place of the general password to gain access rights that are a subset of the access rights that would be granted if the general password were used instead.

Constraining a login to a subset of access rights

A communication channel has an associated channel authenticator that includes a channel identifier, a use policy identifying how an owner of the communication channel indicates the communication channel is used, and a digital signature over the channel identifier and use policy. The identifier of the communication channel and the use policy can be verified by a computing device, and a check made as to whether a current security policy of the computing device is satisfied by the use policy. An access that the computing device is allowed to have to the communication channel is determined based at least in part on both whether the current security policy is satisfied by the use policy and whether the identifier of the communication channel and the use policy are verified.

Communication channel access based on channel identifier and use policy

A portable secure data file includes an encrypted data portion and a metadata portion. When a request associated with a current user of a device to access a portable secure data file is received, one or more records in the metadata portion are accessed to determine whether the current user is permitted to access the file data in the encrypted data portion. If a record indicates the user is permitted to access the file data, a content encryption key in that record is used to decrypt the encrypted data portion.

Portable secure data files

A Universal Serial Bus (USB) compatible storage device is utilized as a security token for storage of cryptographic keys. A cryptographic subsystem of a processor accesses cryptographic keys in containers on the USB compatible storage device. Accessing includes storing and/or retrieving. The processor does not include an infrastructure dedicated to the USB compatible storage device. Cryptographic key storage is redirected from an in-processor container to the USB compatible storage device. No password or PIN is required to access the cryptographic keys, yet enhanced security is provided. Utilizing a USB compatible storage device for a cryptographic key container provides a convenient, portable, mechanism for carrying the cryptographic key, and additional security is provided via physical possession of the device.

Cryptographic key containers on a USB token

Growing community of inventors

Seattle, WA, United States of America

Carl Melvin Ellison