Cryptographic processing device and cryptographic processing method

A cryptographic processing method comprising:

• generating a first encrypted polynomial by encrypting, by a cryptographic processing device, a first polynomial that corresponds to a first binary vector obtained by performing a binary transformation on elements of a first vector;
• and
• transmitting, by the cryptographic processing device, cryptographic information that represents the first encrypted polynomial to a cryptographic operation device that multiplies the first encrypted polynomial by a second encrypted polynomial to generate a third encrypted polynomial,
• wherein the cryptographic processing device or another cryptographic processing device generates the second encrypted polynomial by encrypting a second polynomial that corresponds to a second binary vector obtained by performing a binary transformation on elements of a second vector, and
• wherein an analysis device obtains a result of an operation of the first vector and the second vector by assigning 2 to a variable in a prescribed portion of a third polynomial obtained by decrypting the third encrypted polynomial.

A non-transitory computer-readable recording medium having stored therein a cryptographic processing program for causing a computer to execute a cryptographic process comprising:

• generating a first encrypted polynomial by encrypting a first polynomial that corresponds to a first binary vector obtained by performing a binary transformation on elements of a first vector;
• and
• transmitting cryptographic information that represents the first encrypted polynomial to a cryptographic operation device that multiplies the first encrypted polynomial by a second encrypted polynomial to generate a third encrypted polynomial,
• wherein the computer or a cryptographic processing device generates the second encrypted polynomial by encrypting a second polynomial that corresponds to a second binary vector obtained by performing a binary transformation on elements of a second vector, and
• wherein an analysis device obtains a result of an operation of the first vector and the second vector by assigning 2 to a variable in a prescribed portion of a third polynomial obtained by decrypting the third encrypted polynomial.