scdaemon - Smartcard daemon for the GnuPG system
scdaemon [--homedir dir] [--options file]
[options] --server
scdaemon [--homedir dir] [--options file]
[options] --daemon [command_line]
The scdaemon is a daemon to manage smartcards. It is usually invoked by
gpg-agent and in general not used directly.
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 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.
To install GnuPG as a portable application under Windows,
create an empty file named ‘gpgconf.ctl’ in the
same directory as the tool ‘gpgconf.exe’. The root
of the installation is then that directory; or, if
‘gpgconf.exe’ has been installed directly below a
directory named ‘bin’, its parent directory. You
also need to make sure that the following directories exist and are
writable: ‘ROOT/home’ for the GnuPG home and
‘ROOT/var/cache/gnupg’ for internal cache
files.
- -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 is
‘libpcsclite.so’. 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’).
- --ctapi-driver library
- Use library to access the smartcard reader. The current default is
‘libtowitoko.so’. Note that the use of this interface
is deprecated; it may be removed in future releases.
- --disable-ccid
- Disable the integrated support for CCID compliant readers. This allows
falling back to one of the other drivers even if the internal CCID driver
can handle the reader. Note, that CCID support is only available if libusb
was available at build time.
- --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 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.
scdaemon supports the card applications as described below.
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).
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.
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).
This is common framework for smart card applications. It is used
by gpgsm.
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.
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.
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.
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
distribution
- 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’.
gpg-agent(1), gpgsm(1), gpg2(1)
The full documentation for this tool is maintained as a Texinfo
manual. If GnuPG and the info program are properly installed at your site,
the command
should give you access to the complete manual including a menu
structure and an index.