Messages

1

Botdev / Re: SRP proof?

« on: September 11, 2008, 10:24:42 am »

I think S_exp needs to be taken mod N, yes?

I thought taking (Sbase ^ Sexp) % n was sufficient?  I cross referenced this with the bncsutils code and that is what they have also as far as I can tell.

2

Botdev / Re: SRP proof?

« on: September 10, 2008, 06:47:37 pm »

Yes you are right, and with that it looks to me like your operations are in order for S.

My notes have:
Sc = (((n+B-v) % n) ^ (xu+a)) % n

And you have:
tmp = B
Sbase = n
Sbase += tmp
Sbase -= v
Sbase %= n
Sexp = x
Sexp *= u
Sexp += a
Sc = (Sbase ^ Sexp) % n

These seem like equal operations so I am going to have to assume your S function is correct barring library issues.

As a side note, in your K function it seems to me like odd and even are oppositely named, this shouldn't effect your result though.

3

Botdev / Re: SRP proof?

« on: September 10, 2008, 03:15:40 pm »

Not totally sure about this, but your derivation of 'u' seems off.  Should you not treat it similarly to x and run storm.SBigFromBinary(u, hash, 20); on it?  Instead you are doing something different which could be causing the problem