Covert Communication Scheme Based on Bitcoin Transaction Mechanism

Algorithm 3

Secret information extraction algorithm.

Input: Key K, symmetric key k.
Output: Secret information m, the ID of the special transaction ID_Ts.
(1)	;
(2)	; /∗K and k are negotiated in advance ∗/
(3)	;
(4)	;
(5)	;
(6)	;
(7)	;
(8)	;
(9)	return m, ID_Ts;
(10)	end;