Multiple Key Management

An integrated circuit for acting as an accelerator subsystem for processing data and writing results of the processing to a storage, the integrated circuit comprising:

• a plurality of sets of processors, wherein each of the processors is operable to issue write requests to write data to the storage;
• an encryption unit comprising a memory configured to store a plurality of keys that are associated with the sets of processors, wherein the encryption unit comprises processing circuitry configured to:
• receive a write request issued by a first processor belonging to one of the sets of processors, the write request comprising data to be written to the storage;
• identify from the write request, a first one of the keys that is associated with the one of the sets of processors to which the first processor belongs;
• using the first one of the keys, perform encryption operations with respect to the data contained in the write request to form encrypted data;
• and
• cause the write request to be sent to the storage so as to write the encrypted data to the storage.

A method for decrypting data read by a processing unit comprising a plurality of sets of processors;

• wherein each of the processors is operable to issue read requests to read data from a storage and to process the data read from storage, the method comprising:
• storing a plurality of keys that are associated with the sets of processors;
• receiving a read completion formed in response to a read request issued by a first processor belonging to one of the sets of processors, the read completion comprising data read from the storage;
• identifying from one or more identifier bits in the read completion, a first one of the keys that is associated with the one of the sets of processors to which the first processor belongs;
• using the first one of the keys, performing decryption operations with respect to the data contained in the read completion to form decrypted data;
• and
• causing the read completion to be returned to the first processor with the decrypted data.

A method for encrypting data written by a processing unit comprising a plurality of sets of processors, wherein each of the processors is operable to process data and issue write requests to write results of processing the data to a storage, the method comprising:

• storing a plurality of keys, wherein each of at least some of the keys are associated with different ones of the sets of processors;
• receiving a write request issued by a first processor belonging to one of the sets of processors, the write request comprising data to be written to the storage;
• identifying from the write request, a first one of the keys that is associated with the one of the sets of processors to which the first processor belongs;
• using the first one of the keys, performing encryption operations with respect to the data contained in the write request to form encrypted data;
• and
• causing the write request to be sent to the storage.

A computer program comprising storing computer readable instructions which, when executed by at least one processor, cause a method for decrypting data read by a processing unit to be carried out, the processing unit comprising a plurality of sets of processors, wherein each of the processors is operable to issue read requests to read data from a storage and to process the data read from the storage, the method comprising:

• storing a plurality of keys that are associated with the sets of processors;
• receiving a read completion formed in response to a read request issued by a first processor belonging to one of the sets of processors, the read completion comprising data read from the storage;
• identifying from the read completion, a first one of the keys that is associated with the one of the sets of processors to which the first processor belongs;
• using the first one of the keys, performing decryption operations with respect to the data contained in the read completion to form decrypted data;
• and
• causing the read completion to be returned to the first processor with the decrypted data.

A computer program comprising storing computer readable instructions which, when executed by at least one processor, cause a method for encrypting data written by a processing unit to be carried out, the processing unit comprising a plurality of sets of processors, wherein each of the processors is operable to process data and issue write requests to write results of processing the data to a storage, the method comprising:

• storing a plurality of keys that are associated with different ones of the sets of processors;
• receiving a write request issued by a first processor belonging to one of the sets of processors, the write request comprising data to be written to the storage;
• identifying from the write request, a first one of the keys that is associated with the one of the sets of processors to which the first processor belongs;
• using the first one of the keys, performing encryption operations with respect to the data contained in the write request to form encrypted data;
• and
• causing the write request to be sent to the storage.