On 01/26/2016 08:18 AM, Jorgen Ottosson wrote: > Can't really confirm that here, generating seem not to work either. > > gpg --card-status
Please note that GnuPG 1.4 supports up to 3072-bit. This is because of internal library limitation. I believe that "gpg" in Ubuntu is GnuPG 1.4. It is "gpg2" when we want to use GnuPG 2.0. > gpg/card> generate > Make off-card backup of encryption key? (Y/n) n Besides, generating a key with off-card backup is actually done by two steps: * generating a key on host PC * importing that key to card If your choice is "Yes" for the question above, the key for encryption is not generated on card, but generated on host PC. > I have several readers but am testing here with SCR335. > > Any way to pin-point my issue in more detail? Is my reader known to not > support 4096? Info on readers who will? I also have a scr3500 somewhere > but think I'll have to install drivers for that one to work, the SCR335 > work with internal gpg drivers if I'm not mistaken whereas the 3500 don't > work when attached as is. Unfortunately, I don't have specific information (if card reader works with RSA-4096 or not), either. I maintain this list for internal driver. https://wiki.debian.org/GnuPG/CCID_Driver According to this list, SCR3500 works well with the internal driver of GnuPG. In general, the list by PCSC-lite helps. https://pcsclite.alioth.debian.org/ccid/supported.html Looking the device info, both of SCR335 and SCR3500 work with TPDU level exchange. Thus, I believe that both works well for RSA-4096 keys. > I also find it somewhat hard to get info on support for "Extended length" > in several card reader's product-info pdfs I've looked at. I think that it's "Extended APDU level exchange"? There are two level exchanges; one is TPDU level exchange (lower layer) and another is APDU level exchange. For longer APDU with original OpenPGPcard (i.e., in the communication of RSA-4096), the reader should support: TPDU level exchange or Extended APDU level exchange with enough dwMaxCCIDMessageLength If the reader only support short APDU level exchange, original OpenPGPcard doesn't work well for longer APDU. -- _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users