In an information processing apparatus which can encrypt a file and can
store the encrypted file at a predetermined location, an input file is
separated into a header field and data field, and the separated data
field is encrypted and saved in association with information included in
the header field. In the meantime, a keyword required to specify the file
is extracted from the separated data field, and the extracted keyword is
converted into a hash value. The obtained hash value is stored in
association with the information included in the header field. Upon
storing a file, the contents of the file after storage can be prevented
from being easily recognized by a third party.