Could anyone help me matlab code for SHA-1,SHA-2 and SHA-3?

I would like to perform hashing using SHA-1,SHA-2 and SHA-3. Could anyone guide the link of Matlab code for hashing.

[Walter Roberson]

http://en.cnki.com.cn/Article_en/CJFDTotal-JSJA2012S1115.htm

Answer 1

[Bart McCoy]

MATLAB's internal .net classes support MD5, SHA1, SHA256, SHA384, and SHA512.

I don't think the new SHA3 is available in there yet. Implementation is easy.

I heard about this class from some website (lost the reference), but they didn't have any details.

I was able to guess my way through it without documentation.

% Example Code:    Create an MD5 crypto-hash of an arbitrary string, "str"
% Main class of interest:    System.Security.Cryptography.HashAlgorithm

% Example String to hash with MD5
str = 'hello there big world';

% Create any specified cryptographic hasher. 
% Supported string args include 'MD5', 'SHA1', 'SHA256', 'SHA384', 'SHA512'.
% That's what I could figure out by random guessing...  'SHA3' didn't work.
hasher = System.Security.Cryptography.HashAlgorithm.Create('MD5');

% Convert the char string to uint8 type & run it through the hasher
% This is a Byte[] class object.  Technically, this is the answer, but it needs reformatting
hash_byte = hasher.ComputeHash( uint8(str) );

% Convert the System.Byte class to MATLAB 1xN uint8 number array by typecasting.  Lucky guess here
hash_uint8 = uint8( hash_byte );

% Convert uint8 to a Nx2 char array of HEX values
% Example Result:
%    '12'
%    '58'
%    '2D'  
%    etc.
hash_hex = dec2hex(hash_uint8);

% FINALLY, convert the Nx2 hex char array to a 1x2N format
% Example Result:    '12582D...'
 hashStr = str([]);
 nBytes = length(hash_hex);
 for k=1:nBytes
        hashStr(end+1:end+2) = hash_hex(k,:);
 end

% Final answer is in 'hashStr'
'12582D12558894BE98DDD84E13B305EB'

[javad danesh]

Hi, how do we give the image to its algorithm to give us its code?

[Walter Roberson]

reshape() the image into a vector.

[javad danesh]

thank you.And if you send me the MATLAB code to convert the image to a vector, thank you.

[Walter Roberson]

Image_As_A_vector = reshape(typecast(YourImage, 'uint8'), 1, []));

[Stephan Piotrowski]

Thanks for this example! I have no idea how to find more documentation about the way you define the hasher object. In my case, I wanted to hash numeric arrays rather than a string. For posterity, I'll leave some general learning here. You need to convert the numeric array into a 1D character array before passing it into hasher.ComputeHash. In my case, I chose this method (array_in is an n by 1 numeric array):

array_in=char(strjoin(string(reshape(array_in,1,[]))));

I was then able to proceed much the same way with

hash_byte=hasher.ComputeHash(uint8(array_in));

and so on. In principle, there might be some rare cases where unequal inputs result in the same hash if the conversion to a character array works out in an enexpected way. But it works for my purposes.