NAME
scdaemon - Smartcard daemon for the GnuPG systemSYNOPSIS
scdaemon [--homedir dir] [--options file] [options] --serverDESCRIPTION
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. 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.
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 behavior 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 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 exclusivbe access to teh 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.
- --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
- 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 applications that are not aware of Scdaemon 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 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.
CARD APPLICATIONS
scdaemon supports the card applications as described below.The OpenPGP card application ``openpgp''
The Telesec NetKey card ``nks''
The DINSIG card application ``dinsig''
The PKCS#15 card application ``p15''
The Geldkarte card application ``geldkarte''
The SmartCard-HSM card application ``sc-hsm''
The Undefined card application ``undefined''
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 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’.
SEE ALSO
gpg-agent(1), gpgsm(1), gpg2(1)info gnupg
2022-10-07 | GnuPG 2.2.40 |