Greetings Robert Boyer <[EMAIL PROTECTED]> writes:
> Here is a simple correction to the description I sent you of the RSA > decryption algorithm. I must have been asleep. All I have done here is to > set the constant d to 1. > > Now, the RSA decryption computation simply consists of computing > > m(i) = (( input(i) ) ^ e) mod (p * q) > > for successive i, where p, q, and e are fixed positive integers (with some > other properties not especially relevant to the computation) and each > input(i) in a nonnegative integer less than p*q. We imagine an input > "file" > which we read by asking for successive chunks, input(0), input(1), > input(2), > ..., input(n). We wish to assemble as our answer m(0), m(1), m(2), ..., > m(n). As soon as we have read any input(i), we can fork off a job to > compute > m(i). We don't want to fork off too many jobs, of course, and we do want > to > assemble answers in a timely orderly fashion, maximizing use of available > hardware, writing the output to an output file as and when we can. > > To simplify the example further, one might want to replace (p * q) with just > single constant, say r. > > m(i) = (( input(i) ) ^ e) mod r > > for successive i, where r and e are fixed positive integers (with some ... > > It is also the case that one can assume that e is less than r. > > For all I know, GMP already has a function to do exactly this job very > efficiently. I suspect it might be called gmp_powm. That's what they > seem to call it in PHP, cf. > > http://aspn.activestate.com/ASPN/docs/PHP/function.gmp-powm.html > > So you'd be doing the GCL community a favor by making available directly in > Lisp access to that gmp_powm function (if it does what I think). (And maybe > a host of other gmp functions?) Pushing forward the rest of gmp has been on my todo list for some time. Thus far, I've taken an on-demand approach. Usually, I've tried to integrate these functions into existing common lisp functions, but here I can see no CL function which contains this one (please correct me if wrong). Do we need a gmp package? What are the other functions you would find useful? Take care, > > Bob > > > -- Camm Maguire [EMAIL PROTECTED] ========================================================================== "The earth is but one country, and mankind its citizens." -- Baha'u'llah _______________________________________________ Gcl-devel mailing list Gcl-devel@gnu.org http://lists.gnu.org/mailman/listinfo/gcl-devel
