Utilization of multiple block cipher hashing in authentication and digital signatures

A new algorithm for authentication and digital signature is introduced. It is based on using four different hash functions classified as very secure against all attacks except the brute force one. The hash function used is selected by computing nf_i=r _i mod 4 where r_i is randomly generated and the initial hash sequence H₀ is publicized by the sender. According to nf_i, he/she prepares every message block M_i for encryption by applying a special block cipher technique to obtain the cipher block C_i. Then, the corresponding new hash value H_i is obtained. The value r_i is encrypted to R_i using the sender´s secret RSA key d_s and then the receiver´s public one e_r (this could be reversed if n_r>n_s where n_r and n_s are the modulus numbers of the receiver and sender respectively). The code sent by the sender to the receiver is composed of the combination (C_i, H_i, R_i). This could be useful in checking the integrity of the transmitted message as a whole. The receiver reads the public values H₀, e_s and n_s. Then he/she decrypts the cipher C_i and uses his private RSA key d_r and the senders public one e_s to decrypt R_i. Decryption of C_i yields the prepared block before encryption and decryption of R_i yields the value r_i. Using r_i, the receiver can compute nf_i=r_i mod 4. Using nf_i and H_i-1 , he/she can compute the message block M_i´ and the hash value H_i´. If H_i´=H_i then M_i´=M_i and this means that the message block M_i´ was sent by the sender. If this condition is not satisfied, then the message is either changed or sent by another sender. This algorithm is easy to implement and hard to attack