Abstract: A key protector for a storage volume is created by generating an intermediate key and protecting, based at least in part on a public/private key pair, the intermediate key. A volume master key for encrypting and decrypting one or more volume encryption keys that are used to encrypt the storage volume can be encrypted in different manners, including being encrypted based at least in part on the intermediate key. A key protector for the storage volume is stored that includes both the encrypted volume master key and information indicating how to obtain the intermediate key. Subsequently, the key protector can be accessed and, based at least in part on a private key of the entity associated with the key protector, the intermediate key can be decrypted. The intermediate key can then be used to decrypt the volume master key.

Abstract: Techniques for secure data synchronization are described. In one or more implementations, techniques may be employed to conserve high cost data storage by storing larger portions of encrypted data in low cost storage, while storing relatively smaller encryption keys in higher cost storage. A device that is granted access to the encryption keys can retrieve the encrypted data from the low cost storage and use the encryption keys to decrypt the encrypted data.

Abstract: 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.

Abstract: In embodiments of scalable random number generation, a system includes one or more entropy pools that combine entropy data, which is derived from entropy sources based on event data. A root pseudo-random number generator (PRNG) maintains a seeded entropy state that is reseeded by the entropy pools, and a seed version identifier updates to indicate a current seed version of the root PRNG. Processor PRNGs are instantiated one each per logical processor in a kernel of the system, where each processor PRNG maintains a PRNG entropy state that is reseeded from the root PRNG, and a processor PRNG generates a random number from a respective PRNG entropy state when invoked.

Abstract: Single-use authentication methods for accessing encrypted data stored on a protected volume of a computer are described, wherein access to the encrypted data involves decrypting a key protector stored on the computer that holds a volume-specific cryptographic key needed to decrypt the protected volume. Such single-use authentication methods rely on the provision of a key protector that can only be used once and/or that requires a new access credential for each use. In certain embodiments, a challenge-response process is also used as part of the authentication method to tie the issuance of a key protector and/or access credential to particular pieces of information that can uniquely identify a user.

Abstract: In accordance with one or more aspects, a key protector for a storage volume is created by generating an intermediate key and protecting, based at least in part on a public/private key pair, the intermediate key. A volume master key for encrypting and decrypting one or more volume encryption keys that are used to encrypt the storage volume can be encrypted in different manners, including being encrypted based at least in part on the intermediate key. A key protector for the storage volume is stored that includes both the encrypted volume master key and information indicating how to obtain the intermediate key. Subsequently, the key protector can be accessed and, based at least in part on a private key of the entity associated with the key protector, the intermediate key can be decrypted. The intermediate key can then be used to decrypt the volume master key.

Abstract: 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.

Abstract: In a storage system, multiple information units are individually associated with an access control policy (ACP) of multiple ACPs. Each respective information unit corresponds to a respective information unit encryption key (IUEK). The multiple information units are grouped into encryption zones based on their associated ACPs. In a described implementation, each ACP is associated with a zone root key (ZRK). In another described implementation, each IUEK corresponding to a given information unit is encrypted by an IUEK corresponding to an information unit at a most-proximate linked node of the storage system.

Abstract: In a storage system, multiple information units are individually associated with an access control policy (ACP) of multiple ACPs. Each respective information unit corresponds to a respective information unit encryption key (IUEK). The multiple information units are grouped into encryption zones based on their associated ACPs. In a described implementation, each ACP is associated with a zone root key (ZRK). In another described implementation, each IUEK corresponding to a given information unit is encrypted by an IUEK corresponding to an information unit at a most-proximate linked node of the storage system.