Is it possible to replicate SAS md5 function output via GNU coreutils? - sas

Question

I expected this to be fairly straightforward, but I've run out of ideas this time. I'm working with with GNU coreutils on Windows 7 (not that it should make any difference). I've found another command line utility that does what I want, but I'd prefer to find a way of doing this via GNU md5sum if possible.
Here's what I'm trying to reproduce:
data _null_;
length a $32;
a = put(md5("Hello"), $hex32.);
put a=;
run;
/*Output to replicate: 8B1A9953C4611296A827ABF8C47804D7*/
Here's what I've tried so far:
%macro wincmd /parmbuff;
filename cmd pipe "&SYSPBUFF" lrecl = 32767;
data _null_;
infile cmd lrecl = 32767;
input;
put _infile_;
run;
filename cmd clear;
%mend wincmd;
%let MD5SUM = C:\Program Files (x86)\coreutils\bin\md5sum.exe;
%wincmd(echo Hello | ""&MD5SUM"");
/*Output: f0d07a42adce73f0e4bc2d5e1cdb71e5 *- */
%wincmd(echo Hello | ""&MD5SUM"" -t);
/*Output: adb3f07f896745a101145fc3c1c7b2ea *- */
%wincmd(echo ""Hello"" | ""&MD5SUM"");
/*Output: 2c3a70806465ad43c09fd387e659fbce *- */
%let MD5 = C:\Program Files (x86)\md5\md5.exe;
%wincmd(echo Hello | ""&MD5"");
/*Output: F0D07A42ADCE73F0E4BC2D5E1CDB71E5 (matches md5sum)*/
%wincmd(echo ""Hello"" | ""&MD5"");
/*Output: 2C3A70806465AD43C09FD387E659FBCE (matches md5sum)*/
%wincmd(""&MD5"" -d""Hello"");
/*Output: 8B1A9953C4611296A827ABF8C47804D7 (matches SAS!)*/
Is there some form of syntax I can use with md5sum that will result in the same output (except possibly for upper/lower case differences) as SAS and md5 -d ? And why does the same string produce a different MD5 hash when read from stdin rather than as a command line parameter?
Update: fix, as suggested by DomPazz and Rob:
I thought I might as well go all in with coreutils at this point and match the SAS output exactly:
%let GNUPATH = C:\Program Files (x86)\coreutils\bin;
%let ECHO = &GNUPATH\echo.exe;
%let TR = &GNUPATH\tr.exe;
%let CUT = &GNUPATH\cut.exe;
%wincmd(""&ECHO"" -n ""Hello"" | ""&MD5SUM"" | ""&TR"" '[a-f]' '[A-F]' | ""&CUT"" -f 1 -d "" "");
/*Output: 8B1A9953C4611296A827ABF8C47804D7*/

Answer 1

You problem is not in md5sum, but in echo. It is adding white space to the "Hello" string.
Verify
C:\>echo Hello > c:\temp\test.txt
C:\>md5sum c:\temp\test.txt
-- I get: f0d07a42adce73f0e4bc2d5e1cdb71e5
Now open the file and notice the white space and a newline. Delete those
Run
C:\>md5sum c:\temp\test.txt
-- I get 8b1a9953c4611296a827abf8c47804d7, which matches SAS.
EDIT:
As mentioned in the comments below GNU echo has the -n option to strip the white space.
C:\Cygwin\bin>echo.exe -n Hello | md5sum.exe
returns: 8b1a9953c4611296a827abf8c47804d7
which matches the SAS value.

Answer 2

The MD5 algorithm output is only affected by 2 things as far as I'm aware:
case of source string
length of source string (includes leading/trailing blanks, length of empty string, etc.)
My guess is that the reason you are getting different outputs is because the different approaches pass in the string to hash with different (perhaps default) lengths and/or leading/trailing blanks, or perhaps your quotes are being included in the hash.