Signature Algorithm

Digital signature is an important part of CyberBaller, which ensures the security of CyberBaller system.

The signature algorithm includes three parts, namely, the signer's key generation algorithm, the signature generation algorithm, and the signature verification algorithm.

Digital signatures have two important properties: Only the owner can make his own signature, but anyone who sees it can verify that it is valid; second, the signature is only associated with a specific document, the signature cannot be used to indicate that the owner supports another different files.

The digital signature scheme consists of the following three algorithms:

1. (sk, pk):=generateKeys (keysie); the generateKeys method takes keysize as input to generate a pair of public and private keys. The private key sk is kept securely and used to sign a message; the public key pk is available to anyone and can be used to verify the signature.

2.sig: =sig(sk, message); The signature process takes a message and a private key as an input, and the corresponding message output is a signature.

3. isValid: =verify(sk, message, sig); The verification process is to use a message, a signed message and a public key as input, if the returned result is true, the signature is proved to be true; if the returned result is false, the signature is proved The message is false.

At the same time, it is required to have the following two properties：

1. A valid signature can be verified, ie: Verify(pk, message, sign(sk, message))==true.

2. The signature cannot be forged.