Crypt a message with matlab [closed] - matlab

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I have one question.
I didn't work with MatLab before.
how I read a message from a file. text? and how I crypt and decrypt it?
I need this work for my study project.

Answer 1

To read text:
fid=fopen(filename,'r');
text=fread(fid,'*char')';
fclose(fid);
To encrypt you can use whatever encrpytion suite you want. look here for aes implementation.
Very simple enc/dec algorithem is xoring the text with some key:
filename=('my_cypher.m');
key='Justin Bieber'; %some very secret key
fprintf('\n------------Text-------------\n');
fid=fopen(filename,'r');
text=fread(fid,'*char')';
fclose(fid);
text(text==13)=[]; %remove windows CR for readablity
disp(text);
key=uint8(key);
text=uint8(text);
lenkey=length(key);
text(end+1:end+lenkey-mod(length(text),lenkey))=32; %add extra spaces for reshape.
fprintf('\n------------Cipher-------------\n');
cipher = reshape(bitxor(reshape(text,[],lenkey),key),1,[]);
disp(char(cipher));
fprintf('\n------------Decrpyt-------------\n');
decrpyt = reshape(bitxor(reshape(cipher,[],lenkey),key),1,[]);
disp(char(decrpyt));