128 bit MD5 checksum: file, string, byte stream [MEX]
This function calculates a 128 bit checksum for arrays and files.
Digest = CalcMD5(Data, [InClass], [OutClass])
INPUT:
Data: Data array or file name. Either numerical or CHAR array.
Currently only files and arrays with up to 2^32 bytes (2.1GB) are
accepted.
InClass: String to declare the type of the 1st input.
Optional. Default: 'Char'.
'File': [Data] is a file name as string. The digest is calculated
for this file.
'Char': [Data] is a char array to calculate the digest for. Only the
ASCII part of the Matlab CHARs is used, such that the digest
is the same as if the array is written to a file as UCHAR,
e.g. with FWRITE.
'Unicode': All bytes of the input [Data] are used to calculate the
digest. This is the standard for numerical input.
OutClass: String, format of the output. Just the first character matters.
Optional, default: 'hex'.
'hex': [1 x 32] string as lowercase hexadecimal number.
'HEX': [1 x 32] string as uppercase hexadecimal number.
'Dec': [1 x 16] double vector with UINT8 values.
'Base64': [1 x 22] string, encoded to base 64 (A:Z,a:z,0:9,+,/).
OUTPUT:
Digest: A 128 bit number is replied in a format depending on [OutClass].
The chance, that different data sets have the same MD5 sum is about
2^128 (> 3.4 * 10^38). Therefore MD5 can be used as "finger-print"
of a file rather than e.g. CRC32.
EXAMPLES:
Three methods to get the MD5 of a file:
1. Direct file access (recommended):
MD5 = CalcMD5(which('CalcMD5.m'), 'File')
2. Import the file to a CHAR array (binary mode for exact line breaks!):
FID = fopen(which('CalcMD5.m'), 'rb');
S = fread(FID, inf, 'uchar=>char');
fclose(FID);
MD5 = CalcMD5(S, 'char')
3. Import file as a byte stream:
FID = fopen(which('CalcMD5.m'), 'rb');
S = fread(FID, inf, 'uint8=>uint8');
fclose(FID);
MD5 = CalcMD5(S, 'unicode'); // 'unicode' can be omitted here
Test string:
CalcMD5(char(0:511), 'char', 'HEX')
=> F5C8E3C31C044BAE0E65569560B54332
CalcMD5(char(0:511), 'unicode', 'HEX')
=> 3484769D4F7EBB88BBE942BB924834CD0001 function MD5 = CalcMD5(Data, InClass, OutClass) 0002 % 128 bit MD5 checksum: file, string, byte stream [MEX] 0003 % This function calculates a 128 bit checksum for arrays and files. 0004 % Digest = CalcMD5(Data, [InClass], [OutClass]) 0005 % INPUT: 0006 % Data: Data array or file name. Either numerical or CHAR array. 0007 % Currently only files and arrays with up to 2^32 bytes (2.1GB) are 0008 % accepted. 0009 % InClass: String to declare the type of the 1st input. 0010 % Optional. Default: 'Char'. 0011 % 'File': [Data] is a file name as string. The digest is calculated 0012 % for this file. 0013 % 'Char': [Data] is a char array to calculate the digest for. Only the 0014 % ASCII part of the Matlab CHARs is used, such that the digest 0015 % is the same as if the array is written to a file as UCHAR, 0016 % e.g. with FWRITE. 0017 % 'Unicode': All bytes of the input [Data] are used to calculate the 0018 % digest. This is the standard for numerical input. 0019 % OutClass: String, format of the output. Just the first character matters. 0020 % Optional, default: 'hex'. 0021 % 'hex': [1 x 32] string as lowercase hexadecimal number. 0022 % 'HEX': [1 x 32] string as uppercase hexadecimal number. 0023 % 'Dec': [1 x 16] double vector with UINT8 values. 0024 % 'Base64': [1 x 22] string, encoded to base 64 (A:Z,a:z,0:9,+,/). 0025 % 0026 % OUTPUT: 0027 % Digest: A 128 bit number is replied in a format depending on [OutClass]. 0028 % The chance, that different data sets have the same MD5 sum is about 0029 % 2^128 (> 3.4 * 10^38). Therefore MD5 can be used as "finger-print" 0030 % of a file rather than e.g. CRC32. 0031 % 0032 % EXAMPLES: 0033 % Three methods to get the MD5 of a file: 0034 % 1. Direct file access (recommended): 0035 % MD5 = CalcMD5(which('CalcMD5.m'), 'File') 0036 % 2. Import the file to a CHAR array (binary mode for exact line breaks!): 0037 % FID = fopen(which('CalcMD5.m'), 'rb'); 0038 % S = fread(FID, inf, 'uchar=>char'); 0039 % fclose(FID); 0040 % MD5 = CalcMD5(S, 'char') 0041 % 3. Import file as a byte stream: 0042 % FID = fopen(which('CalcMD5.m'), 'rb'); 0043 % S = fread(FID, inf, 'uint8=>uint8'); 0044 % fclose(FID); 0045 % MD5 = CalcMD5(S, 'unicode'); // 'unicode' can be omitted here 0046 % 0047 % Test string: 0048 % CalcMD5(char(0:511), 'char', 'HEX') 0049 % => F5C8E3C31C044BAE0E65569560B54332 0050 % CalcMD5(char(0:511), 'unicode', 'HEX') 0051 % => 3484769D4F7EBB88BBE942BB924834CD 0052 0053 % Tested: Matlab 6.5, 7.7, 7.8, WinXP, [UnitTest] 0054 % Author: Jan Simon, Heidelberg, (C) 2009-2010 J@n-Simon.De 0055 % License: This program is derived from the RSA Data Security, Inc. 0056 % MD5 Message Digest Algorithm, RFC 1321, R. Rivest, April 1992 0057 % 0058 % See also CalcCRC32. 0059 % Michael Kleder has published a Java call to compute the MD5 (and further 0060 % 0061 % $JRev: R5.00j V:015 Sum:zh2gTrvHwbd7 Date:17-Dec-2009 02:46:53 $ 0062 % $File: CalcMD5\CalcMD5.m $ 0063 % History: 0064 % 015: 15-Dec-2009 16:53, BUGFIX: UINT32 has 32 bits on 64 bit systems now. 0065 % Thanks to Sebastiaan Breedveld! 0066 % 0067 % Copyright (c) 2009, Jan Simon 0068 % All rights reserved. 0069 % Redistribution and use in source and binary forms, with or without 0070 % modification, are permitted provided that the following conditions are 0071 % met: 0072 % 0073 % * Redistributions of source code must retain the above copyright 0074 % notice, this list of conditions and the following disclaimer. 0075 % * Redistributions in binary form must reproduce the above copyright 0076 % notice, this list of conditions and the following disclaimer in 0077 % the documentation and/or other materials provided with the distribution 0078 % 0079 % THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 0080 % AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 0081 % IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 0082 % ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 0083 % LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 0084 % CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 0085 % SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 0086 % INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 0087 % CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 0088 % ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 0089 % POSSIBILITY OF SUCH DAMAGE. 0090 % 0091 % If the current Matlab path is the parent folder of this script, the 0092 % MEX function is not found - change the current directory! 0093 %error(['JSim:', mfilename, ':NoMex'], 'Cannot find MEX script.'); 0094