On 15/02/2011 11:17, Toni Sjoblom - Aventra wrote:

 > Current MyEID cards are 80K, but some of this space is used by the MyEID
 > applet itself.
 >
 > The file size you see in the 3F00 file is the remaining free space, 
but due
 > to a limitation of java cards in general, as Martin mentioned, 32k is the
 > largest number for signed short.
 > This only shows that you have at least this amount o space left. To 
get to
 > know how much space you actually have left, you could create a file 
that is
 > 32k, and the see how much space is left. Then if you still get the 
maximum
 > (32k), then create another 32k file and then see the results. By
 > adding these values together you get the actual space.
Now testing has started.
Actual free space available is about 60K (~20k of the 80k are used by 
Aventra's app, as you said).
After init w/ my modified sizes, I could create 3 files of 16384bytes 
and there were about 10K still free.

 > A single key (private or public) needs typically 70-90 bytes in the 
dir file
 > (index file). The actual amount depends on the label length.
 > One 1024bit RSA key pair takes 512bytes and one 2048bit key pair takes
 > 960bytes.
I have 4 client certs, all from StartSSL (so they have one common "root" 
CA and 2 different "intermediate" CAs). pkcs15-init, rightfully, stores 
a single copy of the duplicate certs.

After loading those certs, I have:
$ opensc-explorer
OpenSC Explorer version 0.12.0
Using reader with a card: Gemalto GemPC Twin 00 00
OpenSC [3F00]> cd 5015
OpenSC [3F00/5015]> info

Dedicated File  ID 5015

File path:     3F00/5015
File size:     28548 bytes
DF name:       \xA0\x00\x00\x00cPKCS-15
ACL for SELECT:          N/A
ACL for LOCK:            N/A
ACL for DELETE:          CHV1
ACL for CREATE:          CHV1
ACL for REHABILITATE:    N/A
ACL for INVALIDATE:      N/A
ACL for LIST FILES:      N/A
ACL for CRYPTO:          N/A
ACL for DELETE SELF:     N/A
Proprietary attributes:  00 02
Security attributes:     11 1F FF

OpenSC [3F00/5015]> ls
FileID  Type  Size
  4401    wEF   384
  5031    wEF   256
  5032    wEF    57
  4946    wEF   128
  4B01    iEF  2048
  4402    wEF  2880
  4301    wEF  1682
  4404    wEF  8640
  4302    wEF  1997
  4303    wEF  2022
  4B02    iEF  2048
  4304    wEF  1700
  4305    wEF  1592
  4B03    iEF  2048
  4306    wEF  1700
  4B04    iEF  2048
  4307    wEF  1740
  4308    wEF  1592
OpenSC [3F00/5015]>

Now I generate a keypair (rsa/2048) and I see only 24052 bytes free. So 
a 2048bit key requires 4496 bytes, that's quite a lot more than 960 
bytes Toni said... But that's partially explained by the fact that these 
are the new files I find:
  4B05    iEF  2048
  5501    wEF   270
  4403    wEF  2880
So there are 2880 bytes less to consider.
But 2048+270 remains a lot more than 960...

Seems the private key uses 1 byte for every bit. If I use -G rsa/1024 
its EF 4Bxx is 1024 bytes. Is that normal?

BYtE!
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