Mercurial > hg > ltpda
view m-toolbox/classes/+utils/@prog/hash.m @ 46:ca0b8d4dcdb6 database-connection-manager
Fix
author | Daniele Nicolodi <nicolodi@science.unitn.it> |
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date | Tue, 06 Dec 2011 19:07:27 +0100 |
parents | f0afece42f48 |
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function h = hash(inp,meth) % HASH - Convert an input variable into a message digest. % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % HASH - Convert an input variable into a message digest using any of % several common hash algorithms % % USAGE: h = hash(inp,'meth') % % inp = input variable, of any of the following classes: % char, uint8, logical, double, single, int8, uint8, % int16, uint16, int32, uint32, int64, uint64 % h = hash digest output, in hexadecimal notation % meth = hash algorithm, which is one of the following: % MD2, MD5, SHA-1, SHA-256, SHA-384, or SHA-512 % % NOTES: (1) If the input is a string or uint8 variable, it is hashed % as usual for a byte stream. Other classes are converted into % their byte-stream values. In other words, the hash of the % following will be identical: % 'abc' % uint8('abc') % char([97 98 99]) % The hash of the follwing will be different from the above, % because class "double" uses eight byte elements: % double('abc') % [97 98 99] % You can avoid this issue by making sure that your inputs % are strings or uint8 arrays. % (2) The name of the hash algorithm may be specified in lowercase % and/or without the hyphen, if desired. For example, % h=hash('my text to hash','sha256'); % (3) Carefully tested, but no warranty. Use at your own risk. % (4) Michael Kleder, Nov 2005 % (5) This is a direct copy of the code from Michael Kleder. Only % the function name was changed to bring it in line with the % LTPDA naming convention. (M Hewitson 15-09-07) % % EXAMPLE: % % algs={'MD2','MD5','SHA-1','SHA-256','SHA-384','SHA-512'}; % for n=1:6 % h=hash('my sample text',algs{n}); % disp([algs{n} ' (' num2str(length(h)*4) ' bits):']) % disp(h) % end % % NOTE: Original taken from MATHWORKS file exchange. % Author: Michael Kleder, Nov 2005 % http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=8944&objectType=file % % $Id: hash.m,v 1.1 2008/06/18 13:35:11 hewitson Exp $ % % inp=inp(:); % convert strings and logicals into uint8 format if ischar(inp) || islogical(inp) inp=uint8(inp); else % convert everything else into uint8 format without loss of data inp=typecast(inp,'uint8'); end % verify hash method, with some syntactical forgiveness: meth=upper(meth); switch meth case 'SHA1' meth='SHA-1'; case 'SHA256' meth='SHA-256'; case 'SHA384' meth='SHA-384'; case 'SHA512' meth='SHA-512'; otherwise end algs={'MD2','MD5','SHA-1','SHA-256','SHA-384','SHA-512'}; if isempty(strmatch(meth,algs,'exact')) error(['Hash algorithm must be ' ... 'MD2, MD5, SHA-1, SHA-256, SHA-384, or SHA-512']); end % create hash x=java.security.MessageDigest.getInstance(meth); x.update(inp); h=typecast(x.digest,'uint8'); h=dec2hex(h)'; if(size(h,1))==1 % remote possibility: all hash bytes < 128, so pad: h=[repmat('0',[1 size(h,2)]);h]; end h=lower(h(:)'); clear x return