摘要 |
OBJECT To provide an information processing apparatus, a program and a storage medium capable of performing an efficient computation of a GHASH function. MEANS OF SOLUTION An information processing apparatus has an encryption part that encrypts by block encryption, and is embeddable in an electronic apparatus, and achieves the above object by segmenting an authentication target message into one or more blocks for every 128 bits, the authentication target message including at least a predetermined authentication parameter and first encryption information that is obtained by encrypting plaintext information by the encryption part, successively computing each of the one or more segmented blocks by a GHASH function including a predetermined algorithm, using a plurality of 8-bit arrays including 16 elements, and generating second encryption information that is obtained by encrypting a computed result by the encryption part, to generate an authentication tag. |