El Gamal e-signature

This protocol is executed between you named as student Alice and Mentor Bob.

It is strongly recommended that you use Octave software implemented in your local computer rather than to use Octave in the server.

Public parameters (PP) known for all parties are strong prime number p=178096967 and generator g=20, where p is 28 bits length. Please check it for awareness.

Computed numerical parameter values sent by Alice must be included in the input field denoted by brackets [ ]. E.g., if Alice under the Mentor request computed parameters r=64823413 and s=18072906, then symbolically in the input field she must enter [r,s] which corresponds to enter 64823413, 18072906 in the input field without brackets.

The following functions are used in the protocol:

>> mod_exp(g,x,p);          % function computes modular exponent value g^x mod p                             

>> randi(i);                        % i=26 – is recommended an upper range of generated random integer number

>> H26('message')            % message means message to be signed