Abstract: There is provided mechanisms for handling instances of a trusted execution environment on an execution platform. The trusted execution environment is associated with a secure cryptoprocessor. The secure cryptoprocessor holds a register. The trusted execution environment is configured to read from and write to the register at a given index i. A method is performed by the trusted execution environment. The method comprises checking, upon start of a new instance of the trusted execution environment, status of the register at the given index i, and wherein, when the register at the given index i has its status set to “undefined”, an internal status value is set to a first value, and else, when a value is read from the register at the given index i, the internal status value is set to a second value based on the read value. The method comprises writing the internal status value to the register at the given index i. The method comprises running the new instance.

Abstract: A method is disclosed of a secure component (SC) of a local attestation server (LAS) for populating an enclave associated with the LAS. The SC comprises stored encrypted population information previously received in a data packet and encrypted by an encryption key matching a private decryption key of a trusted platform module (TPM) associated with the LAS. The method comprises receiving a public part of a temporary asymmetric key from the enclave, establishing a secure session between the SC and the TPM, sending (to the TPM by using the secure session) the encrypted population information and the public part of the temporary asymmetric key, receiving (from the TPM by using the secure session) the population information decrypted by the private decryption key and re-encrypted by the public part of the temporary asymmetric key, and transmitting the re-encrypted population information to the enclave. An additional method is also disclosed for enabling the population of the enclave.

Abstract: There is provided mechanisms for handling instances of a trusted execution environment on an execution platform. The trusted execution environment is associated with a secure cryptoprocessor. The secure cryptoprocessor holds a register. The trusted execution environment is configured to read from and write to a volatile part of the register at a given index i. A method is performed by the trusted execution environment. The method comprises checking, upon start of a new instance of the trusted execution environment, status of the register at the given index i. The method comprises enabling the new instance to keep running only when successfully reading a first value representing no currently run instance of the trusted execution environment from the register at the index i or if the register at the given index i has its status set to “undefined” when checking the status.

Abstract: There is provided mechanisms for attesting a first TEE residing on a first node. A method is performed by a second TEE also residing on the first node. The method comprises obtaining a request from the first TEE to be attested. The method comprises, in response thereto, obtaining a shared key from a third TEE residing on a second node. The method comprises performing local attestation of the first TEE, whereby the first TEE is provided with the shared key from the second TEE.

Abstract: There is provided mechanisms for handling instances of a trusted execution environment on an execution platform. The trusted execution environment is associated with a secure cryptoprocessor. The secure cryptoprocessor holds a register. The trusted execution environment is configured to read from and write to the register at a given index i. A method is performed by the trusted execution environment. The method comprises checking, upon start of a new instance of the trusted execution environment, status of the register at the given index i, and wherein, when the register at the given index i has its status set to “undefined”, an internal status value is set to a first value, and else, when a value is read from the register at the given index i, the internal status value is set to a second value based on the read value. The method comprises writing the internal status value to the register at the given index i. The method comprises running the new instance.

Abstract: A method is disclosed of a secure component (SC) of a local attestation server (LAS) for populating an enclave associated with the LAS. The SC comprises stored encrypted population information previously received in a data packet and encrypted by an encryption key matching a private decryption key of a trusted platform module (TPM) associated with the LAS. The method comprises receiving a public part of a temporary asymmetric key from the enclave, establishing a secure session between the SC and the TPM, sending (to the TPM by using the secure session) the encrypted population information and the public part of the temporary asymmetric key, receiving (from the TPM by using the secure session) the population information decrypted by the private decryption key and re-encrypted by the public part of the temporary asymmetric key, and transmitting the re-encrypted population information to the enclave. An additional method is also disclosed for enabling the population of the enclave.

Abstract: There is provided mechanisms for handling instances of a trusted execution environment on an execution platform. The trusted execution environment is associated with a secure cryptoprocessor. The secure cryptoprocessor holds a register. The trusted execution environment is configured to read from and write to a volatile part of the register at a given index i. A method is performed by the trusted execution environment. The method comprises checking, upon start of a new instance of the trusted execution environment, status of the register at the given index i. The method comprises enabling the new instance to keep running only when successfully reading a first value representing no currently run instance of the trusted execution environment from the register at the index i or if the register at the given index i has its status set to “undefined” when checking the status.