Difference in SHA hashes between ruby and C#

Question

I'm developing an application, that makes use of some REST web services. It's technical documentation says that I should pass SHA256 hash of some string in the request.

In an example request (in the documentation) a string:

hn-Rw2ZHYwllUYkklL5Zo_7lWJVkrbShZPb5CD1expires=1893013926label[0]=any/somestatistics=1d,2d,7d,28d,30d,31d,lifetimestatus=upl,livetitle=a

After executing:

digest = Digest::SHA256.digest(string_to_sign)
signature = Base64::encode64(digest).chomp.gsub(/=+$/, '')

results in a hash:

YRYuN2zO+VvxISNp/vKQM5Cl6Dpzoin7mNES0IZJ06U

This example is in ruby, as the documentation is for ruby developers.

I'm developing my application in C# and for the exactly same string, when I execute:

byte[] rawHash = sha256.ComputeHash(rawRequest, 0, rawRequest.Length);
string friendlyHash = Convert.ToBase64String(rawHash);

and remove the trailing "=" signs, I get:

Vw8pl/KxnjcEbyHtfNiMikXZdIunysFF2Ujsow8hyiw

and therefore, the application fails to execute resulting in an signature mismatch error.

I've tried changing the encoding while converting the string to a byte array preceding the hashing and nothing changed.

Any ideas?

Have you trimmed the string? Might be a space in there somewhere. — stimms
– stimms, Commented Jun 12, 2009 at 1:56
Can you send us the string you are using. I can not replicate your results in ruby either.. — Ryan Oberoi
– Ryan Oberoi, Commented Jun 12, 2009 at 2:01
FYI, with Python I'm getting RuVTyg6Wc5vL51Z4goeRGAqTdb1ioHknFihtyRzKlvw -- curiouser and curiouser, said Alice... — Alex Martelli
– Alex Martelli, Commented Jun 12, 2009 at 2:12
Your test string is wrong. The documentation uses hn-Rw2ZH-YwllUYkklL5Zo_7lWJVkrbShZPb5CD1expires=1893013926label[0]=any/somestatistics=1d,2d,7d,28d,30d,31d,lifetimestatus=upl,livetitle=a — Stobor
– Stobor, Commented Jun 12, 2009 at 2:33

Jack Bolding · Accepted Answer · 2009-06-12 02:36:15Z

8

Based on the document here, you are missing a - (that is a dash) in your string. Seems that Acrobat helpfully removes it in a copy paste from the document...

Here is some code that I splatted together that gets the same value as the example (well it would if you trimmed the final =)

    string s = "hn-Rw2ZH-YwllUYkklL5Zo_7lWJVkrbShZPb5CD1expires=1893013926label[0]=any/somestatistics=1d,2d,7d,28d,30d,31d,lifetimestatus=upl,livetitle=a";

    SHA256Managed sh = new SHA256Managed();
    byte[] request = System.Text.UTF8Encoding.UTF8.GetBytes(s);
    sh.Initialize();
    byte[] b4bbuff = sh.ComputeHash(request, 0, request.Length);

    string b64 = Convert.ToBase64String(b4bbuff);

answered Jun 12, 2009 at 2:36

Jack Bolding

3,8293 gold badges43 silver badges46 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Stobor Over a year ago

What you said. I should probably have put that in an answer.

Collectives™ on Stack Overflow

Difference in SHA hashes between ruby and C#

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related