US 12,395,352 B2
Quantum digital signature method and quantum digital signcryption method
Hua-Lei Yin, Nanjing (CN); Chen-Xun Weng, Nanjing (CN); Yao Fu, Nanjing (CN); and Zeng-Bing Chen, Nanjing (CN)
Assigned to NANJING UNIVERSITY, Nanjing (CN); and MATRICTIME DIGITAL TECHNOLOGY CO., LTD, Nanjing (CN)
Appl. No. 18/247,151
Filed by NANJING UNIVERSITY, Jiangsu (CN); and MATRICTIME DIGITAL TECHNOLOGY CO., LTD, Nanjing (CN)
PCT Filed Sep. 14, 2022, PCT No. PCT/CN2022/118785
§ 371(c)(1), (2) Date Mar. 29, 2023,
PCT Pub. No. WO2023/082823, PCT Pub. Date May 19, 2023.
Claims priority of application No. 202111336020.2 (CN), filed on Nov. 12, 2021.
Prior Publication US 2024/0364533 A1, Oct. 31, 2024
Int. Cl. H04L 9/32 (2006.01); G06F 21/45 (2013.01); G06F 21/60 (2013.01); G06F 21/64 (2013.01); G06N 10/00 (2022.01); H04L 9/08 (2006.01)
CPC H04L 9/3247 (2013.01) [H04L 9/0852 (2013.01); H04L 9/0869 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A quantum digital signing method, comprising:
(1) a step of preparing secret keys, wherein a signing party, a receiving party and a verifying party respectively holding two strings of random secret keys, and secret sharing being formed among the secret keys of the signing party, the receiving party and the verifying party;
(2) a step of generating a signature:
obtaining, by a random number generator of the signing party, an n-bit true random number, wherein the n-bit true random number is used to generate an irreducible polynomial;
generating, by the signing party, a hash function based on a linear feedback shift register by using a first string of secret key of the signing party, serving as an input random number, together with the irreducible polynomial; obtaining, by the signing party, a hash value by inputting a message to be signed into the hash function; then a message digest is formed by the hash value and a character string comprised of coefficients of terms of respective orders except the highest order of the irreducible polynomial;
generating, by the signing party, a signature by performing an unconditionally secure encryption on the message digest using a second string of secret key of the signing party;
(3) a step of verifying the signature:
sending, by the signing party, the message to be signed and the signature as a whole to the receiving party; the receiving party, upon reception, sending its two strings of secret keys, the message to be signed and the signature to the verifying party; the verifying party, upon reception, sending its two strings of secret keys to the receiving party; deducing, by the receiving party and the verifying party respectively, the two strings of secret keys of the signing party according to secret keys held by the receiving party and the verifying party;
performing decryption operation on the signature by the receiving party and the verifying party respectively using second strings of secret key of the signing party deduced by the receiving party and the verifying party to obtain a first backward digest and a second backward digest; generating an irreducible polynomial by successively corresponding respective bits in a character string of each of the first backward digest and the second backward digest to coefficients of terms of respective orders other than the highest order of the irreducible polynomial, where a coefficient of the highest order is 1; generating hash functions using the generated irreducible polynomial and first strings of secret keys of the signing party respectively deduced by the receiving party and the verifying party, and inputting the received message to be signed into the generated hash functions to generate a first forward hash value of the receiving party and a second forward hash value of the verifying party; wherein in a case that the first forward hash value is equal to a hash value in the first backward digest, the receiving party accepts the signature, otherwise the receiving party does not accept the signature, in a case that the second forward hash value is equal to a hash value in the second backward digest, the verifying party accepts the signature, otherwise the verifying party does not accept the signature, and digital signing is completed when both the receiving party and the verifying party accept the signature at the same time.