Secure rebuilding of an encoded data slice in a dispersed storage network

A method comprises:

• receiving a partial rebuilding request, wherein the request includes a key pair;
• retrieving an encoded data slice associated with the partial encoded data slice request;
• generating a partial encoded data slice based on the partial rebuilding request and the encoded data slice associated with the request;
• multiple encrypting the partial encoded data slice using the key pair to produce an encrypted partial encoded data slice;
• and
• outputting the encrypted partial encoded data slice.

A rebuilding module comprises:

• a first module for identifying an encoded data slice to be rebuilt;
• a second module for selecting a decode threshold number of dispersed storage (DS) units of a storage set of DS units associated with the encoded data slice to be rebuilt;
• a third module for generating a decode threshold number of key pairs, wherein a key pair of the decode threshold number of key pairs corresponds to a DS unit of the decode threshold number of DS units;
• a fourth module for sending partial rebuilding requests to the decode threshold number of DS units, wherein a partial rebuilding request of the partial rebuilding requests includes the key pair and identity of the corresponding DS unit;
• a fifth module for receiving encrypted partial encoded data slices in response to the partial rebuilding requests, wherein an encrypted partial encoded data slice received from the corresponding DS unit includes a multiple encryption, using the key pair, of a partial encoded data slice;
• and
• a sixth module for decoding the encrypted partial encoded data slices to rebuild the encoded data slice.

A rebuilding module comprises:

• a first module for receiving a partial rebuilding request, wherein the request includes a key pair;
• a second module for retrieving an encoded data slice associated with the partial encoded data slice request;
• a third module for generating a partial encoded data slice based on the partial rebuilding request and the encoded data slice associated with the request;
• a fourth module for multiple encrypting the partial encoded data slice using the key pair to produce an encrypted partial encoded data slice;
• and
• a fifth module for outputting the encrypted partial encoded data slice.