Ubuntu Manpage: scdaemon - Smartcard daemon for the GnuPG system

Provided by: scdaemon_2.4.4-2ubuntu17.3_amd64

NAME

       scdaemon - Smartcard daemon for the GnuPG system

SYNOPSIS

       scdaemon [--homedir dir] [--options file] [options] --server
       scdaemon [--homedir dir] [--options file] [options] --daemon [command_line]

DESCRIPTION

       The  scdaemon  is  a  daemon to manage smartcards.  It is usually invoked by gpg-agent and in general not
       used directly.

COMMANDS

       Commands are not distinguished from options except for the fact that only one command is allowed.

       --version
              Print the program version and  licensing  information.   Note  that  you  cannot  abbreviate  this
              command.

       --help, -h
              Print  a  usage  message  summarizing  the most useful command-line options.  Note that you cannot
              abbreviate this command.

       --dump-options
              Print a list of all available options and commands.  Note that you cannot abbreviate this command.

       --server
              Run in server mode and wait for commands on the stdin.  The default mode is to create a socket and
              listen for commands there.

       --multi-server
              Run in server mode and wait for commands on the stdin as well as  on  an  additional  Unix  Domain
              socket.  The server command GETINFO may be used to get the name of that extra socket.

       --daemon
              Run  the program in the background.  This option is required to prevent it from being accidentally
              running in the background.

OPTIONS

--options file
Reads configuration from file instead of from the default per-user configuration file. The
default configuration file is named ‘scdaemon.conf’ and expected in the ‘.gnupg’ directory
directly below the home directory of the user.

--homedir dir
Set the name of the home directory to dir. If this option is not used, the home directory defaults
to ‘~/.gnupg’. It is only recognized when given on the command line. It also overrides any home
directory stated through the environment variable ‘GNUPGHOME’ or (on Windows systems) by means of
the Registry entry HKCU\Software\GNU\GnuPG:HomeDir.

On Windows systems it is possible to install GnuPG as a portable application. In this case only
this command line option is considered, all other ways to set a home directory are ignored.

-v

--verbose
Outputs additional information while running. You can increase the verbosity by giving several
verbose commands to gpgsm, such as ‘-vv’.

--debug-level level
Select the debug level for investigating problems. level may be a numeric value or a keyword:

none No debugging at all. A value of less than 1 may be used instead of the keyword.

basic Some basic debug messages. A value between 1 and 2 may be used instead of the keyword.

advanced
More verbose debug messages. A value between 3 and 5 may be used instead of the keyword.

expert Even more detailed messages. A value between 6 and 8 may be used instead of the keyword.

guru All of the debug messages you can get. A value greater than 8 may be used instead of the
keyword. The creation of hash tracing files is only enabled if the keyword is used.

How these messages are mapped to the actual debugging flags is not specified and may change with newer
releases of this program. They are however carefully selected to best aid in debugging.

All debugging options are subject to change and thus should not be used by any application
program. As the name says, they are only used as helpers to debug problems.

--debug flags
Set debug flags. All flags are or-ed and flags may be given in C syntax (e.g. 0x0042) or as a
comma separated list of flag names. To get a list of all supported flags the single word "help"
can be used. This option is only useful for debugging and the behavior may change at any time
without notice.

--debug-all
Same as --debug=0xffffffff

--debug-wait n
When running in server mode, wait n seconds before entering the actual processing loop and print
the pid. This gives time to attach a debugger.

--debug-ccid-driver
Enable debug output from the included CCID driver for smartcards. Using this option twice will
also enable some tracing of the T=1 protocol. Note that this option may reveal sensitive data.

--debug-disable-ticker
This option disables all ticker functions like checking for card insertions.

--debug-allow-core-dump
For security reasons we won't create a core dump when the process aborts. For debugging purposes
it is sometimes better to allow core dump. This option enables it and also changes the working
directory to ‘/tmp’ when running in --server mode.

--debug-log-tid
This option appends a thread ID to the PID in the log output.

--debug-assuan-log-cats cats
Changes the active Libassuan logging categories to cats. The value for cats is an unsigned
integer given in usual C-Syntax. A value of 0 switches to a default category. If this option is
not used the categories are taken from the environment variable ASSUAN_DEBUG. Note that this
option has only an effect if the Assuan debug flag has also been with the option --debug. For a
list of categories see the Libassuan manual.

--no-detach
Don't detach the process from the console. This is mainly useful for debugging.

--listen-backlog n
Set the size of the queue for pending connections. The default is 64. This option has an effect
only if --multi-server is also used.

--log-file file
Append all logging output to file. This is very helpful in seeing what the agent actually does.
Use ‘socket://’ to log to socket.

--pcsc-shared
Use shared mode to access the card via PC/SC. This is a somewhat dangerous option because
Scdaemon assumes exclusive access to the card and for example caches certain information from the
card. Use this option only if you know what you are doing.

--pcsc-driver library
Use library to access the smartcard reader. The current default on Unix is ‘libpcsclite.so’ and
on Windows ‘winscard.dll’. Instead of using this option you might also want to install a symbolic
link to the default file name (e.g. from ‘libpcsclite.so.1’). A Unicode file name may not be used
on Windows.

--disable-ccid
The integrated CCID driver for CCID compliant devices can be available when libusb was detected at
build time, and it is used to access the smartcard reader. If access via PC/SC driver is needed,
please configure this option to disable CCID driver support (if any). In GnuPG 2.2, there was a
fallback mechanism from CCID driver to PC/SC driver. The fallback mechanism worked, because
scdaemon in GnuPG 2.2 only supported a single token/reader. To support of multiple tokens/readers
at the same time, fallback mechanism was removed.

--reader-port number_or_string
This option may be used to specify the port of the card terminal. A value of 0 refers to the
first serial device; add 32768 to access USB devices. The default is 32768 (first USB device).
PC/SC or CCID readers might need a string here; run the program in verbose mode to get a list of
available readers. The default is then the first reader found.

To get a list of available CCID readers you may use this command:
echo scd getinfo reader_list \
| gpg-connect-agent --decode | awk '/^D/ {print $2}'

--card-timeout n
This option is deprecated. In GnuPG 2.0, it used to be used for DISCONNECT command to control
timing issue. Since DISCONNECT command works synchronously, it has no effect.

--enable-pinpad-varlen
Please specify this option when the card reader supports variable length input for pinpad (default
is no). For known readers (listed in ccid-driver.c and apdu.c), this option is not needed. Note
that if your card reader doesn't supports variable length input but you want to use it, you need
to specify your pinpad request on your card.

--disable-pinpad
Even if a card reader features a pinpad, do not try to use it.

--deny-admin
This option disables the use of admin class commands for card applications where this is
supported. Currently we support it for the OpenPGP card. This option is useful to inhibit
accidental access to admin class command which could ultimately lock the card through wrong PIN
numbers. Note that GnuPG versions older than 2.0.11 featured an --allow-admin option which was
required to use such admin commands. This option has no more effect today because the default is
now to allow admin commands.

--disable-application name
This option disables the use of the card application named name. This is mainly useful for
debugging or if a application with lower priority should be used by default.

--application-priority namelist
This option allows one to change the order in which applications of a card a tried if no specific
application was requested. namelist is a space or comma delimited list of application names.
Unknown names are simply skipped. Applications not mentioned in the list are put in the former
order at the end of the new priority list.

To get the list of current active applications, use
gpg-connect-agent 'scd getinfo app_list' /bye

All the long options may also be given in the configuration file after stripping off the two leading
dashes.

CARD APPLICATIONS

scdaemon supports the card applications as described below.

The OpenPGP card application ``openpgp''

This application is currently only used by gpg but may in future also be useful with gpgsm. Version 1
and version 2 of the card is supported.

The specifications for these cards are available at
(http://g10code.com/docs/openpgp-card-1.0.pdf) and
(http://g10code.com/docs/openpgp-card-2.0.pdf).

The Telesec NetKey card ``nks''

This is the main application of the Telesec cards as available in Germany. It is a superset of the
German DINSIG card. The card is used by gpgsm.

The DINSIG card application ``dinsig''

This is an application as described in the German draft standard DIN V 66291-1. It is intended to be
used by cards supporting the German signature law and its bylaws (SigG and SigV).

The PKCS#15 card application ``p15''

This is common framework for smart card applications. It is used by gpgsm.

The Geldkarte card application ``geldkarte''

This is a simple application to display information of a German Geldkarte. The Geldkarte is a small
amount debit card application which comes with almost all German banking cards.

The SmartCard-HSM card application ``sc-hsm''

This application adds read-only support for keys and certificates stored on a (http://www.smartcard-
hsm.com, SmartCard-HSM).

To generate keys and store certificates you may use (https://github.com/OpenSC/OpenSC/wiki/SmartCardHSM,
OpenSC) or the tools from (http://www.openscdp.org, OpenSCDP).

The SmartCard-HSM cards requires a card reader that supports Extended Length APDUs.

The Undefined card application ``undefined''

This is a stub application to allow the use of the APDU command even if no supported application is found
on the card. This application is not used automatically but must be explicitly requested using the
SERIALNO command.

EXAMPLES

         $ scdaemon --server -v

FILES

       There  are  a  few configuration files to control certain aspects of scdaemons's operation. Unless noted,
       they are expected in the current home directory (see: [option --homedir]).

       scdaemon.conf
              This is the standard configuration file read by scdaemon on startup.  It  may  contain  any  valid
              long  option;  the  leading  two  dashes may not be entered and the option may not be abbreviated.
              This default name may be changed on the command line (see: [option --options]).

       scd-event
              If this file is present and executable, it will be called on every card  reader's  status  change.
              An  example  of  this  script  is  provided  with  the  source  code distribution.  This option is
              deprecated in favor of the DEVINFO --watch.

       reader_n.status
              This file is created by scdaemon to let other applications now about reader status  changes.   Its
              use is now deprecated in favor of ‘scd-event’.