"Robert J. Hansen" <[EMAIL PROTECTED]> writes: >> >> What prevents the keylogger in your first example to snarf the PIN >> code >> for the OpenPGP card and send decryption requests to the OpenPGP card, >> using the PIN code, in the background, possibly remotely controlled >> over >> the network? > > There exist cryptographic smart cards you can actually be safe > against this kind of attack with. They're pretty cool. I don't know > Smart-card has nothing to do with it. It's the OS who has to defend against such type of attack. AFAIK, no wide-spread OS does it today. On linux, you can strace any application and see all I/O done by the program. On Windows you have even more powerful debugging/interception API. Windows is slightly better here because an administrator can revoke the "Debug Privilege" from a user account. Thus, the user can't debug its own programs, but neither the trojans can, so it makes running sensitive applications slightly safer.
As long as OS allows ptrace/equivalent calls which inspect and modify data and code in another process, there's NO WAY to prevent this attack. Not even separate PIN entry device helps, because the trojan may still attach itself to (eg.) GnuPG executable and modify data (eg. to-be signed hash) in memory before it's sent to the smart-card. Intel had once a whitepaper on LaGrande technology where every application would be cryptographically protected *in hardware* from any other application. Each app would have cryptographically protected channel with I/O devices, and even memory regions. Such environment would fully protect applications like GnuPG. But, AFAIK, it remained only a whitepaper. > > The question isn't whether smart cards are secure--nothing that's got > that much RAM and processor power ever is--but whether smart cards > are a security improvement. > My personal opinion is that, at the current state of "security" in today's OS-es, smart cards give just a false sense of security in typical usage scenarios (= when used on a general-purpose, networked workstation). _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users
