Abstract: A digital signature over a message may be compressed by determining a plurality of values based at least in part on the message. A mapping of the plurality of values over a digital signature scheme may be used to determine a value from which a portion of the compressed digital signature is decompressible by cryptographically deriving one or more components of the uncompressed digital signature. A public key may be used to verify the authenticity of the compressed digital signature and message.

Abstract: A tiered credentialing approach provides assurance to customers having virtual machines running in a remote environment that the virtual images for these machines are in a pristine state and running in a trusted execution environment. The environment can be divided into multiple subsystems, each having its own cryptographic boundary, secure storage, and trusted computing capabilities. A trusted, limited subsystem can handle the administrative tasks for virtual machines running on the main system of a host computing device. The limited system can receive a certificate from a certificate authority, and can act as a certificate authority to provide credentials to the main system. Upon an attestation request, the subsystems can provide attestation information using the respective credentials as well as the certificate chain. An entity having the appropriate credentials can determine the state of the system from the response and verify the state is as expected.

Abstract: A service includes an associated service request throttling system. The throttling system constrains the rate at which service requests are fulfilled by the service, and also provides throttling information to the service. The throttling system controls service throughput by implementing a throttling bucket. The throttling bucket has an associated bucket level which indicates, to the service, an amount of service requests that can be satisfied before throughput limitations are imposed by the throttling system. The bucket level may be modified in response to service requests, service request characteristics, or environmental parameters. In some examples, operational parameters of the throttling system may be configured by users of the service to constrain data exfiltration. The bucket level itself may be used by the service to expand or constrain access privileges granted to particular users.

Abstract: A computer system encodes a plurality of components of a data set into a probabilistic data structure and digitally signs the probabilistic data structure. The computer system provides the digital signature for the probabilistic data structure and the probabilistic data structure to various entities. An entity can verify an individual component of the data set within the probabilistic data structure by verifying the individual component against the probabilistic data structure and the digital signature of the probabilistic data structure.

Abstract: A system performs cryptographic operations utilizing information usable to verify validity of plaintext. To prevent providing information about a plaintext by providing the information usable to verify the validity of the plaintext, the system provides the information usable to verify validity of the plaintext to an entity on a condition that the entity is authorized to access the plaintext. The information usable to verify validity of the plaintext may be persisted in ciphertext along with the plaintext to enable the plaintext to be verified when decrypted.

Abstract: A cryptography service allows for management of cryptographic keys and for the evaluation of security expectations when processing incoming requests. In some contexts, the cryptography service, upon receiving a request to perform a cryptographic operation, evaluates a set of security expectations to determine whether the cryptographic key or keys usable to perform the cryptographic operation should be trusted. A response to the request is dependent on evaluation of the security expectations.

Abstract: An HSM management hub coordinates the distribution and synchronization of cryptographic material across a fleet of connected hardware security modules (“HSMs”). Cryptographic material is exchanged between HSMs in the fleet in a cryptographically protected format. In some examples, the cryptographic material is encrypted using a common fleet key maintained by the HSMs in the fleet. In other examples, the cryptographic material is protected using asymmetric cryptographic keys that are associated with the members of the HSM fleet. The HSM management hub may be used to divide the HSM fleet into subdomains by providing domain keys to subsets of HSMs within the HSM fleet. Cryptographic information that is encrypted with particular domain keys can be distributed across the entire HSM fleet, and restricted to use by authorized HSMs that are in possession of the particular domain keys.

Abstract: A digital signature over a message may be compressed by determining a plurality of values based at least in part on the message. A mapping of the plurality of values over a digital signature scheme may be used to determine a value from which a portion of the compressed digital signature is decompressible by cryptographically deriving one or more components of the uncompressed digital signature. A public key may be used to verify the authenticity of the compressed digital signature and message.

Abstract: A data storage management process is directed to aspects of managing encrypted data via data storage volumes in conjunction with a service provider computer network that hosts virtual machine instances. A volume can be created and configured for managing encrypted data with an encrypted version of a volume key. The volume can be attached to a virtual machine instance such that the virtual machine instance accesses the volume in a transparent fashion based on the volume key. Encrypted data specific to the volume can be copied across multiple regions of data storage each associated with distinct encrypted versions of a volume key corresponding to the volume.

Abstract: A trusted co-processor can provide a hardware-based observation point into the operation of a host machine owned by a resource provider or other such entity. The co-processor can be installed via a peripheral card on a fast bus, such as a PCI bus, on the host machine. The provider can provide the customer with expected information that the customer can verify through a request to an application programming interface (API) of the card, and after the customer verifies the information the customer can take logical ownership of the card and lock out the provider. The card can then function as a trusted but limited environment that is programmable by the customer. The customer can subsequently submit verification requests to the API to ensure that the host has not been unexpectedly modified or is otherwise operating as expected.

Abstract: A computer system encodes a plurality of components of a data set into a probabilistic data structure and digitally signs the probabilistic data structure. The computer system provides the digital signature for the probabilistic data structure and the probabilistic data structure to various entities. An entity can verify an individual component of the data set within the probabilistic data structure by verifying the individual component against the probabilistic data structure and the digital signature of the probabilistic data structure.

Abstract: A trusted co-processor can provide a hardware-based observation point into the operation of a host machine owned by a resource provider or other such entity. The co-processor can be installed via a peripheral card on a fast bus, such as a PCI bus, on the host machine. The provider can provide the customer with expected information that the customer can verify through a request to an application programming interface (API) of the card, and after the customer verifies the information the customer can take logical ownership of the card and lock out the provider. The card can then function as a trusted but limited environment that is programmable by the customer. The customer can subsequently submit verification requests to the API to ensure that the host has not been unexpectedly modified or is otherwise operating as expected.

Abstract: A proof-of-work system where a first party (e.g., a client computer system) may request access to a computing resource. A second party (e.g., a service provider) may determine a challenge that may be provided to the first party. A valid solution to the challenge may be generated and provided for the request to be fulfilled. The challenge may include a message and a seed, such that the seed may be used at least in part to cryptographically derive information that may be used to generate a solution to the challenge. A hash tree may be generated as of generating the solution.

Abstract: A data storage management process is directed to aspects of managing encrypted data via data storage volumes in conjunction with a service provider computer network that hosts virtual machine instances. A volume can be created and configured for managing encrypted data with an encrypted version of a volume key. The volume can be attached to a virtual machine instance such that the virtual machine instance accesses the volume in a transparent fashion based on the volume key. Encrypted data specific to the volume can be copied across multiple regions of data storage each associated with distinct encrypted versions of a volume key corresponding to the volume.

Abstract: A client and server negotiate a secure communication channel using a pre-shared key where the server, at the time the negotiation initiates, lacks access to the pre-shared key. The server obtains the pre-shared key from another server that shares a secret with the client. A digital signature or other authentication information generated by the client may be used to enable the other server to determine whether to provide the pre-shared key.

Abstract: A system performs cryptographic operations utilizing information usable to verify validity of plaintext. To prevent providing information about a plaintext by providing the information usable to verify the validity of the plaintext, the system provides the information usable to verify validity of the plaintext to an entity on a condition that the entity is authorized to access the plaintext. The information usable to verify validity of the plaintext may be persisted in ciphertext along with the plaintext to enable the plaintext to be verified when decrypted.

Abstract: A service provider provides virtual computing services using a fleet of one or more host computer systems. Each of the host computer systems may be equipped with a trusted platform module (“TPM”). The service provider, the host computer systems, and the virtual computing environments generate attestations that prove the integrity of the system. The attestations are signed with a one-time-use cryptographic key that is verifiable against the public keys of the service provider, a host computer system, and a virtual computing environment. The public key of the host computer system is integrated into a hash tree that links the public key of the host computer system to the public key of the service provider. The public key of the virtual computing environment is signed using a one-time-use graphic key issued to the host computer system that hosts the virtual computing environment.

Abstract: A client establishes a cryptographically protected communications session with a server. To detect a man-in-the-middle, the client echoes information about a certificate purportedly received from the server. The information echoed by the client is digitally signed so as to be verifiable by the server without any cryptographic key used in the cryptographically protected communications session or its establishment, thereby rendering the echoed information unmodifiable by a man-in-the-middle without invalidating the signature. The server can therefore verify both the echoed information and the digital signature to determine whether it has established a cryptographically protected communications session with the client or with a man-in-the-middle purporting to be the client.

Abstract: A proof-of-work system where a first party (e.g., a client computer system) may request access to a computing resource. A second party (e.g., a service provider) may determine a challenge that may be provided to the first party. A valid solution to the challenge may be generated and provided for the request to be fulfilled. The challenge may include a message and a seed, such that the seed may be used at least in part to cryptographically derive information that may be used to generate a solution to the challenge. A hash tree may be generated as of generating the solution.

Abstract: A tiered credentialing approach provides assurance to customers having virtual machines running in a remote environment that the virtual images for these machines are in a pristine state and running in a trusted execution environment. The environment can be divided into multiple subsystems, each having its own cryptographic boundary, secure storage, and trusted computing capabilities. A trusted, limited subsystem can handle the administrative tasks for virtual machines running on the main system of a host computing device. The limited system can receive a certificate from a certificate authority, and can act as a certificate authority to provide credentials to the main system. Upon an attestation request, the subsystems can provide attestation information using the respective credentials as well as the certificate chain. An entity having the appropriate credentials can determine the state of the system from the response and verify the state is as expected.