A method for securing a device environment comprising: determining, at a computing device, a device profile that identifies a single-purpose or a multi-purpose target device, as well as components of the target device; determining, at the computing device, a hash mask that defines a first scope of hash computation, including identifying all components of the target device whose signatures are to be included in a trusted hash computation; and computing, at the computing device, the trusted hash computation based on the signatures of the identified components to create a first signature having the first defined scope; characterised by: receiving, at the computing device, an updated device profile of the target device, including an update to one or more of the identified components; re-computing (332, 334), at the computing device, the trusted hash computation based on the signatures of the updated identified components to create a second signature having the first defined scope; receiving a request at the computing device requesting a third signature, the request identifying a second scope of hash computation to be performed to generate the third signature to verify integrity; computing the third signature by computing a trusted hash computation based on the second scope of hash computation requested; and transmitting the third signature for verification in response to the request. determining, at a computing device, a device profile that identifies a single-purpose or a multi-purpose target device, as well as components of the target device; determining, at the computing device, a hash mask that defines a first scope of hash computation, including identifying all components of the target device whose signatures are to be included in a trusted hash computation; and computing, at the computing device, the trusted hash computation based on the signatures of the identified components to create a first signature having the first defined scope; characterised by: receiving, at the computing device, an updated device profile of the target device, including an update to one or more of the identified components; re-computing (332, 334), at the computing device, the trusted hash computation based on the signatures of the updated identified components to create a second signature having the first defined scope; receiving a request at the computing device requesting a third signature, the request identifying a second scope of hash computation to be performed to generate the third signature to verify integrity; computing the third signature by computing a trusted hash computation based on the second scope of hash computation requested; and transmitting the third signature for verification in response to the request. receiving, at the computing device, an updated device profile of the target device, including an update to one or more of the identified components; re-computing (332, 334), at the computing device, the trusted hash computation based on the signatures of the updated identified components to create a second signature having the first defined scope; receiving a request at the computing device requesting a third signature, the request identifying a second scope of hash computation to be performed to generate the third signature to verify integrity; computing the third signature by computing a trusted hash computation based on the second scope of hash computation requested; and transmitting the third signature for verification in response to the request.