Abstract: Embodiments of the present disclosure provide a method, an apparatus, and a system for authenticating a fully homomorphic message, where the method includes: acquiring a message authentication key, where: the message authentication key includes a public key, a first character string, and a second character string; the first character string is a character string that consists of 0 and 1 and has a length of n; the second character string is a character string that consists of 0 and 1 and has a length of n; generating an authentication fingerprint corresponding to each bit of to-be-computed data; sending a computation request to a server; receiving an authentication fingerprint corresponding to the computation result; and performing correctness authentication on the computation result according to the received authentication fingerprint, which effectively reduces an amount of computation in a verification process.

Abstract: Embodiments of the present disclosure provide a method, an apparatus, and a system for authenticating a fully homomorphic message, where the method includes: acquiring a message authentication key, where: the message authentication key includes a public key, a first character string, and a second character string; the first character string is a character string that consists of 0 and 1 and has a length of n; the second character string is a character string that consists of 0 and 1 and has a length of n; generating an authentication fingerprint corresponding to each bit of to-be-computed data; sending a computation request to a server; receiving an authentication fingerprint corresponding to the computation result; and performing correctness authentication on the computation result according to the received authentication fingerprint, which effectively reduces an amount of computation in a verification process.

Abstract: Embodiments of the present invention provide a key insulation method and device. The key insulation method includes: randomly selecting a first parameter s from Z*q, acquiring a helper initial key from a helper, and generating an initial user private key according to the first parameter s, a preset first cryptographic hash function H1, and the helper initial key; and acquiring a helper updated key for a time segment i from the helper, and updating a user private key for a time segment j according to the helper updated key for the time segment i to obtain a user private key for the time segment i. According to the key insulation method and device provided by the embodiments, in a process of generating an initial key and a process of updating a key, lifecycle is not involved, which improves flexibility of a key system.

Abstract: Embodiments of the present invention provide a key insulation method and device. The key insulation method includes: randomly selecting a first parameter s from Z*q, acquiring a helper initial key from a helper, and generating an initial user private key according to the first parameter s, a preset first cryptographic hash function H1, and the helper initial key; and acquiring a helper updated key for a time segment i from the helper, and updating a user private key for a time segment j according to the helper updated key for the time segment i to obtain a user private key for the time segment i. According to the key insulation method and device provided by the embodiments, in a process of generating an initial key and a process of updating a key, lifecycle is not involved, which improves flexibility of a key system.