| 摘要 |
<p>Whether or not restored secret information has been manipulated is detected. Secret information is encoded and distributed into distributed information in accordance with an access structure, by choosing polynomial coefficients randomly, a random number sequence is generated having the number of pieces in which the aforementioned secret information has been distributed, the aforementioned coefficients are encoded and distributed into random number information in accordance with the access structure, a hash value generates a hash function corresponding to the aforementioned random number sequence, by choosing a key that forms the aforementioned hash function, data for checking for manipulation of the restored secret data are independently set as an amount of checking data corresponding to the number of pieces in which the aforementioned secret information has been distributed, the aforementioned distributed information is read, the aforementioned secret information is restored in accordance with the aforementioned access structure, the aforementioned random number information is read, the aforementioned random number sequence is restored in accordance with the aforementioned access structure, the aforementioned checking data is read, and when the read checking data satisfies the aforementioned hash function, the aforementioned restored secret information is judged not to have been manipulated.</p> |
