Problem with label formatting in C_GetTokenInfo / opensc 0.20.0

[pboguslawski]

Hello,

There seems to be a problem with label formatting in C_GetTokenInfo in opensc 0.20.0 (compiled in debian 10 from sources https://github.com/OpenSC/OpenSC/releases):

$ PKCS11SPY=/usr/lib/x86_64-linux-gnu/opensc-pkcs11.so PKCS11SPY_OUTPUT=logfile pkcs11-tool -T --module /usr/lib/x86_64-linux-gnu/pkcs11-spy.so

$ cat logfile 
[...]
5: C_GetTokenInfo
2020-01-30 12:55:30.442
[in] slotID = 0x0
[out] pInfo: 
      label:                  '               IBHS001 (UserPIN)'
      manufacturerID:         'www.CardContact.de              '
[...]

original opensc 0.19.0-1 from dpkg in debian 10 returns:

$ PKCS11SPY=/usr/lib/x86_64-linux-gnu/opensc-pkcs11.so PKCS11SPY_OUTPUT=logfile pkcs11-tool -T --module /usr/lib/x86_64-linux-gnu/pkcs11-spy.so

user@d10:~/tmp$ cat logfile 
[...]
5: C_GetTokenInfo
2020-01-30 13:13:10.851
[in] slotID = 0x0
[out] pInfo: 
      label:                  'UserPIN (IBHS001)               '
      manufacturerID:         'www.CardContact.de              '
[...]

This breaks apps like

(*) https://github.com/miekg/pkcs11/blob/master/pkcs11.go#L866

that seems to expect label to be formatted according to

http://docs.oasis-open.org/pkcs11/pkcs11-base/v2.40/os/pkcs11-base-v2.40-os.html

label application-defined label, assigned during token initialization. MUST be padded with the blank character (‘ ‘). MUST NOT be null-terminated.

Debug show, that app (*) reads label as "IBHS001 (UserPIN)<here 15x zero byte>"

Problems:

(1)

Seems that label returned by C_GetTokenInfo from opensc 0.20.0 does not contain padding with spaces - it just ends after last letter. No such problem in manufacturerID field.

(2)

Order of label/pin in final label returned by C_GetTokenInfo is different in 0.19.0 and 0.20.0:

IBHS001 (UserPIN) != UserPIN (IBHS001)

Is it intentional (may require config changes after upgrade to 0.20.0 if one uses label as parameter).

Regards,
Paweł

[frankmorgner]

Duplicate of #1901

Sorry for the inconvenience.

[frankmorgner]

I may have closed this too quickly.

Do I read correctly, that your label is padded with spaces in the front?!

[pboguslawski]

Thank you for checking #1901 - this explains (2) but (1) still needs attention.

Do I read correctly, that your label is padded with spaces in the front?!

Seems spaces added in the front of "IBHS001 (UserPIN)" in pkcs11-tool -T output in 0.20.0 like above are caused by fprintf (%32.32s) used in pkcs11-display.c for displaying label...

https://github.com/OpenSC/OpenSC/blob/master/src/pkcs11/pkcs11-display.c#L928

...and are not part of label - displaying label works here ok.

Label value returned by C_GetTokenInfo seems to be "IBHS001 (UserPIN)" but should be "IBHS001 (UserPIN)<15x space here>" (see oasis info above).

After fixing 0.20.0, pkcs11-tool -T command should NOT probably display

label:                  '               IBHS001 (UserPIN)'

but

label:                  'IBHS001 (UserPIN)               '

[frankmorgner]

please check if #1926 fixes the padding

[pboguslawski]

Just compiled 0.20.0 with fix #1926 applied (Debian 10) and now label works ok. Thank you!

Regards,
Paweł