Patent ID: 9577826
Date: 2017-02-21
CPC Classifications: G06F,H04L

Claim:
1. A cryptographic method implemented in an electronic device, the method comprising operations of: (a) generating a candidate prime number from another prime number in accordance with: where Pr is the candidate prime number, P is a prime number having a number of bits lower than a desired number of bits of the candidate prime number, and R is an integer, wherein a size in number of bits of the candidate prime number is equal to a margin of one bit to three times a size of the prime number; (b) calculating a quotient of an integer division of the integer by the prime number; (c) rejecting the generated candidate prime number in response to detecting that the quotient of the integer division of the integer by the prime number is even; (d) applying the Pocklington primality test to the candidate prime number; (e) storing, in a memory of the electronic device, the candidate prime number as a proven prime number in response to passing the Pocklington primality test, else generating a new candidate prime number and performing operations (b) to (e) again with the new candidate prime number; (f) generating, from the proven prime number, a cryptographic key; and (g) performing, by the electronic device using the cryptographic key, a cryptographic operation on data, the cryptographic operation being one of an encryption operation, a decryption operation, or a verification of a digital signature included in the data.