| 摘要 |
PROBLEM TO BE SOLVED: To strengthen anonymity. SOLUTION: A user U selects an existing certificate CSy and sends a key PBy' of its use condition, a public key PBi as the use condition of a certificate CSj to be issued, a probabilistic cipher text EP (eCH, IDB, and ry) of IDB of a black box V in the certificate CSy, a probabilistic code EID (IDB and r'y), public keys PCP and eCH of a certificate issue station CP, and matters for certification MCPj to the black box B, and the black box B generates a cipher text X obtained by converting EP () and a code Y obtained by converting EID () and subjects (PCP, PBi||X||Y||MCPi, w) to blind function operation to obtain Z and generates W=EP (eCH, w, x) by probabilistic encryption of (w) and signs Z||W||EP()||EID()||MCPi with a secret key SBi of the black box B to obtain sB and sends Z, W, sB, and random numbers (u), (v), (w), and (x) to the user U, and the user U sends Z, W, sB, and CSy to the station CP, and the station CP verities the signature of CSy and confirms whether sB is the signature using SBy'; and if the signature passes both verification and confirmation, the station CP adds a blind signature to Z with the secret key of the station CP and sends this signature s' to the user U, and the user U unblinds the signature s' to obtain sj and obtains X and Y from Sy, (u), and (v) to obtain CSj. |
