SHA1 base64 algorithm in javascript and C#

Question

Hi

I'm running some tests comparing the sha1 algorithm implemented in javascript - got from http://pajhome.org.uk/crypt/ - with its implementation in C#.

Using C# to get the hash for {'method':'people.get'} I'm using this statement:

Convert.ToBase64String(new System.Security.Cryptography.SHA1CryptoServiceProvider().ComputeHash(Encoding.ASCII.GetBytes("{'method':'people.get'}")));

which gives me Qy95a0ShZqhbNdt6IF8qNf72jX0=

In javascript I get almost the same: Qy95a0ShZqhbNdt6IF8qNf72jX0 using the statement:

b64_sha1("{'method':'people.get'}");

In the javascript case, the hash doesn't end with a equal (=) sign.

Can this difference cause me troubles in authenticating against a server?

In my case, as many of you may know, the sentence I'm reckoning the hash goes inside the http body and the server will check it.

Thanks

Answer 1

Would depend on the receiver but try decoding your result from the javascript with C# and you'll get an exception. The = sign is there to pad the result to the correct length.

http://en.wikipedia.org/wiki/Base64

Answer 2

The sha1.js from the lib I mentioned in my question, has a global variable called b64pad, used for the purpose of padding. By default its value is "". Changing to "=" gives the exact hash reckoned by C# API