Re: Two-way on-the-fly encryption

Ray -- ..and then Ray said... % % I want to do two-way encryption on a file coming through the web server. In That's an interesting name for it. % this context, I would want to generate a public and private key, encrypt the % file stream (i.e., don't want to write the unencrypted file to disk first % and then encrypt it; I want to encrypt the stream as it comes in) with the OK. Be aware that it will possibly get written to disk, though. % public, send the private to the recipient, and then destroy both keys on my % end. Hmmm... *thinks* I can't remember if a private key alone is sufficient to decrypt, although the public key alone is certainly enough to encrypt. You might check on that. % % When the file was accessed and the private key was provided, I would want to % stream the unencrypted file out without ever writing the unencrypted file to % disk. Note that your clear text could very well get written to disk: you are very likely to have a swap space. I don't know of any way to tell php that you don't want it (or really the OS) to lock some chunk in memory. % % Any ideas on how to accomplish this within the PHP construct? Well, gnupg can encrypt and decrypt a stream, and there is a GNUPG class at phpclasses.org, so I would probably leave all of the encryption and key work to it and go that way. If you really wanted to be secure, you might implement some javascript or a java applet to encrypt it before it ever left the browser (and, similarly, decrypt it when it's requested later); then you only ever deal with the encrypted version (ick -- I can't believe I just suggested J-anything). % % Thanks! So what in the world is this data which must be so secure that even you can't see it? HTH & HAND :-D -- David T-G * There is too much animal courage in (play) davidtg@justpickone.org * society and not sufficient moral courage. (work) davidtgwork@justpickone.org -- Mary Baker Eddy, "Science and Health" http://justpickone.org/davidtg/ Shpx gur Pbzzhavpngvbaf Qrprapl Npg!