SYNOPSIS
scdaemon [--homedir dir] [--options file] [options] --serverscdaemon [--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. Not that you can
abbreviate this command.
- --help, -h
-
Print a usage message summarizing the most useful command-line options.
Not that you can abbreviate this command.
- --dump-options
-
Print a list of all available options and commands. Not that you can
abbreviate this command.
- --server
-
Run in server mode and wait for commands on the stdin. This is
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.
To install GnuPG as a portable application under Windows, create an empty file name 'gpgconf.ctl' in the same directory as the tool 'gpgconf.exe'. The root of the installation is than 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
-
This option is only useful for debugging and the behaviour may change at
any time without notice. FLAGS are bit encoded and may be given in
usual C-Syntax. The currently defined bits are:
-
- 0 (1)
- command I/O
- 1 (2)
- values of big number integers
- 2 (4)
- low level crypto operations
- 5 (32)
- memory allocation
- 6 (64)
- caching
- 7 (128)
- show memory statistics.
- 9 (512)
- write hashed data to files named dbgmd-000*
- 10 (1024)
- trace Assuan protocol. See also option --debug-assuan-log-cats.
- 11 (2048)
- trace APDU I/O to the card. This may reveal sensitive data.
- 12 (4096)
- trace some card reader related function calls.
-
- --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 options 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 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.
- --log-file file
-
Append all logging output to file. This is very helpful in
seeing what the agent actually does.
- --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 to fall 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
-
If n is not 0 and no client is actively using the card, the card
will be powered down after n seconds. Powering down the card
avoids a potential risk of damaging a card when used with certain
cheap readers. This also allows non Scdaemon aware applications to
access the card. The disadvantage of using a card timeout is that
accessing the card takes longer and that the user needs to enter the
PIN again after the next power up.
Note that with the current version of Scdaemon the card is powered down immediately at the next timer tick for any value of n other than 0.
- --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 commands 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 command 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.
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 certifiates 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 veyer card
reader's status changed. An example of this script is provided with the
distribution
- reader_n.status
-
This file is created by sdaemon to let other applications now
about reader status changes. Its use is now deprecated in favor of
'scd-event'.