Digital signature method, signature information authentication method, and relevant electronic devices

A digital signature method includes: obtaining a to-be-transmitted file, a private key and first compressed data, the first compressed data being obtained through compressing a symmetric tensor, the private key including a first invertible matrix; generating L pieces of second compressed data corresponding to L second symmetric tensors in accordance with the first invertible matrix and the first compressed data; creating a Hash value of a root node in a Hash tree in accordance with L pieces of created data, the L pieces of created data being the L pieces of second compressed data or the L second symmetric tensors; and generating signature information about the to-be-transmitted for the first electronic device in accordance with the first character string, the first invertible matrix, the second invertible matrix, the L pieces of second compressed data and the Hash value of the root node in the Hash tree. [Figure 1] obtaining a to-be-transmitted file, a private key of the first electronic device for digital signature, and first compressed data, the first compressed data being obtained through compressing a randomly generated symmetric tensor, an order of the first symmetric tensor being greater than 2, the private key including a first invertible matrix I, S102 generating L pieces of second compressed data corresponding to L second symmetric tensors in accordance with the first invertible matrix and the first compressed data, the L second symmetric tensors including the first symmetric tensor and symmetric tensors isomorphic to the first symmetric tensor performing digital signature on the to-be-transmitted file in accordance with a randomly-generated second invertible matrix and the first compressed data, so as to obtain a first character string I, S104 creating a Hash value of a root node in a Hash tree in accordance with L pieces of created data, the L pieces of created data being the L pieces of second compressed data or the L second symmetric tensors generating signature information about the to-be-transmitted for the first electronic device in accordance with the first character string, the first invertible matrix, the second invertible matrix, the L pieces of second compressed data and the Hash value of the root node in the Hash tree