Despite what others have said, RSA is perfectly reasonable (if slow) to use for encryption. If you do, you should use OAEP/OAEP+ rather than the common/naive method of padding.
http://cseweb.ucsd.edu/~mihir/papers/oaep.html The Wikipedia article is a good starting place http://en.wikipedia.org/wiki/Optimal_asymmetric_encryption_padding and there's a brief article here http://www.rsa.com/rsalabs/node.asp?id=2346 more detail here ftp://ftp.rsasecurity.com/pub/rsalabs/rsa_algorithm/rsa-oaep_spec.pdf - M On Sat, Jul 10, 2010 at 11:13 AM, Jeffrey Walton <noloa...@gmail.com> wrote: > > The general approach is to encrypt data using a symmetric cipher (e.g., > > AES-256) with a randomly-generated key, and then encrypt that symmetric > key > > with the RSA (public) key. > AES-256 requires a RSA modulus with an equivalent strength, which is a > 15360 (IIRC). If you choose RSA-1024 or RSA-2048, you are off by > orders of magnitude. > > On Thu, Jul 8, 2010 at 11:43 PM, Phillip Hellewell <ssh...@gmail.com> > wrote: > > The general approach is to encrypt data using a symmetric cipher (e.g., > > AES-256) with a randomly-generated key, and then encrypt that symmetric > key > > with the RSA (public) key. > > > > And for the symmetric encryption you'll also have to make a decision > about > > what mode to use (ECB, CBC, CTR, etc). Whatever you do, don't use ECB :) > > > > Phillip > > > > On Thu, Jul 8, 2010 at 7:40 PM, Chuck Pareto <chuckda...@gmail.com> > wrote: > >> > >> Is there an algorithm that I can use, similar to RSA with public/private > >> key, that will allow me to encrypt really long strings (like an > email/text > >> file)? Actually no limit on the size would be ideal. > > > > > ______________________________________________________________________ > OpenSSL Project http://www.openssl.org > User Support Mailing List openssl-users@openssl.org > Automated List Manager majord...@openssl.org >
