Encrypting method, recording medium of encrypting program, decrypting method, and recording medium of decrypting program

摘要

An encrypting method including encrypting a first data segment of encryption target data on the basis of first key information, generating second key information on the basis of the first data segment by using a predetermined algorithm, and encrypting a second data segment of the encryption target data, which is different from the first data segment, on the basis of the second key information.