The application relates to a cross-
modal retrieval method supporting authorized access, and relates to the field of
cloud computing security. A vector inner product
encryption scheme FBIPE realizes the privacy of data and query requests, and an authorized
key tree guarantees low-interactive authorized access. First, text / images in a
database / query request are converted into text / image vectors by using a cross-
modal hashing technology, and all the vectors are encrypted by using the FBIPE. Then, an independent key is generated for each vector in the
database by using the authorized
key tree, and the corresponding text /
image vector ciphertext is re-encrypted by using the key. Finally, in the cross-
modal retrieval process, authorized access is completed because the authorized key corresponding to unauthorized access data cannot be restored. The whole authorized cross-modal retrieval method is based on lightweight
cryptography primitives, and the designed authorized
key tree can realize low-interactive
authorization, and the overall operation efficiency is high.