* scd/app-p15.c (CARD_PRODUCT_GENUA): New.
(cardproduct2str): Add it.
(read_p15_info): Detect and set GENUA
(make_pin_prompt): Take holder string from the AODF.
* scd/command.c (scd_command_handler): Use gnupg_fd_t for the argument
but no INT2FD to listen. Use GNUPG_INVALID_FD.
* tpm2d/command.c (tpm2d_command_handler): Likewise.
* scd/scdaemon.c (start_connection_thread): Follow the change.
* tpm2d/tpm2daemon.c (start_connection_thread): Likewise.
* scd/scdaemon.h (scd_command_handler): Use gnupg_fd_t.
* tpm2d/tpm2daemon.h (tpm2d_command_handler): Likewise.
--
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/scdaemon.c (main): Use gnupg_fd_t for socket, and use
assuan_sock_close for the socket allocated by assuan_sock_new.
(handle_connections): Use gnupg_fd_t for listen_fd.
Use assuan_sock_close for the socket by npth_accept.
--
GnuPG-bug-id: 5029
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/app.c (app_auth): It's only APPTYPE_OPENPGP which supports
the challenge response interaction.
* scd/command.c (cmd_pkauth): It only wants if it works or not.
--
GnuPG-bug-id: 5862
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* sm/certdump.c (parse_dn_part): Translate OID to "Callsign"
* sm/keylist.c (oidtranstbl): Some more OIDs.
--
This is Ham thingy to make it easier to read LotW certificates.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (auth_type_t): New.
(struct aodf_object_s): Add field auth_type.
(read_ef_aodf): Distinguish between pin and authkey types. Include
the authtype in the verbose mode diags.
--
Note that the bulk of chnages are just indentation chnages. There
should be no functional change.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (CARD_TYPE_AET): New.
(cardtype2str): Add string.
(card_atr_list): Add corresponding ATR.
(app_local_s): New flag no_extended_mode. Turn two other flags into
bit flags.
(select_ef_by_path): Hack to handle the 3FFF thing.
(readcert_by_cdf): Do not use etxended mode for AET.
(app_select_p15): Set no_extended_mode.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (read_ef_prkdf, read_ef_pukdf)
(read_ef_cdf, read_ef_aodf): Allow for a zero length path and
correctly skip unsupported auth types.
--
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/iso7816.c (iso7816_read_binary_ext): Handle the 0x6a86 SW the
same as 6b00.
* scd/apdu.c (apdu_get_atr): Modify debug messages.
* scd/app-p15.c (app_select_p15): Print FCI on error.
(read_p15_info): Clean up diag in presence of debug options.
--
Some cards return 6a86 instead of 6b00.
Signed-off-by: Werner Koch <wk@gnupg.org>
* agent/command-ssh.c (ssh_handler_request_identities): Remove double
check of ERR.
* g10/getkey.c (get_pubkey_byname): Remove double use of break.
* g10/pkglue.c (pk_encrypt): Handle possible NULL-ptr access due to
failed malloc.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/apdu.c (open_pcsc_reader): PCSC.COUNT should
be incremented before possible call of close_pcsc_reader.
--
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/apdu.c (pcsc_cancel): New.
(pcsc_init): Load new function.
(connect_pcsc_card): Use it after a removed card error.
--
Well, that was easier than I expected yesterday.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/apdu.c (close_pcsc_reader): Do not decrement refcount if already
zero. Always release context if or becomes zero.
(apdu_dev_list_start): Unlock prior to close_pcsc_reader. For PC/SC
increment the count. Always release the lock.
(apdu_dev_list_finish): No more unlocking. Use close_pcsc_reader
instead of code duplication.
* scd/apdu.c (pcsc_error_string): Add an error code.
* scd/scdaemon.c (scd_kick_the_loop): Fix a diagnostic.
--
There was an obvious bug in that the pcsc.count could go below zero
and thus there was no chance to get the context release. Releasing
and recreating the context is at least under Windows important to get
rit of the PCSC_E_SERVICE_STOPPED.
Also removes a potential problem in holding the reader_table_lock
between calls to apdu_dev_list_start apdu_dev_list_finish. There is
no need for this. Instead we bump the pcsc.count.
The reader_table_lock strategy should be reviewed; we may be able to
remove it.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (read_p15_info): Improve D-TRUST card detection.
(do_getattr): Fix faulty code for the last commit. Append the product
name to MANUFACTURER.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (get_dispserialno): Add dedicated handling for RSCS.
--
In fact we fix the display of the s/n because the s/n was taken from a
certificate.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c: Include openpgpdefs.h.
(struct prkdf_object_s): Add fields have_keytime and ecdh_kdf.
(read_p15_info): Set ecdh_kdf.
(keygrip_from_prkdf): Flag that we have the keytime.
(send_keypairinfo): Send the key time only if valid.
(send_key_fpr_line): New.
(send_key_fpr): New.
(do_getattr): Add KEY-FPR.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (cdf_object_from_label): New.
(cdf_object_from_certid): Fallback to label matching.
(read_p15_info): Ditto.
(keygrip_from_prkdf): Ditto. Replace duplicated code by a call to
cdf_object_from_objid.
--
In case there is no certificate for a private key we now also try to
find a certificate using a matching label.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-nks.c (keygripstr_from_pk_file): Fix ignored error.
(get_nks_tag): New.
(do_learn_status_core): Use it. Make sure not to mange the
KEYPAIRINFO line if no usage is known.
(do_readkey): Output the KEYPAIRINFO for the keygrip case.
--
Note that this only handles the most common case of providing a
keygrip. $AUTHKEYID and ODLM are not yet supported.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-help.c (app_help_get_keygrip_string_pk): Make HEXKEYGRIP
parm optional.
* scd/command.c (do_readkey): Remove duplicate output of keypairinfo
lines.
--
Note that this change needs a fix in app-p15 which does not yet handle
the APP_READKEY_FLAG_INFO.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/ccid-driver.c (ccid_vendor_specific_pinpad_setup): New.
(ccid_vendor_specific_setup): Only send CLEAR_HALT.
(ccid_transceive_secure): Each time, use send_escape_cmd.
--
GnuPG-bug-id: 5297
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/command.c (cmd_learn): Add flag --reread.
* scd/app-common.h (struct app_ctx_s): New field need_reset.
* scd/app.c (write_learn_status_core): Set need_reset if we notice an
error after returning from a reread. Change all callers of card
functions to return GPG_ERR_CARD_RESET so that that app is not anymore
used.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (do_deinit): Factor code out to ...
(release_lists, release_tokeninfo): new.
(read_ef_tokeninfo): Reset all data before reading.
(read_p15_info): Ditto.
(do_learn_status): Implement reread flag.
--
Objects of a card may be protected by a PIN and thus only readble
after a verify command. This new flag makes it possible to gather the
entire PKCS#15 card info again without a need for a reset (and thus
loss of the verify status).
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (do_sign): Rewrite.
--
This basically works now but for my test card I need to pass
--cert-digest-algo-512 manually. Need to check this again and
automate it. It will also be useful to take the NotBefore timestamp
from the dummy X.509 certificate and use that for the PGP key creation
time.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/iso7816.c (iso7816_pso_csv): New.
* scd/app-help.c (app_help_pubkey_from_cert): Uncompress a point if
needed.
* scd/app-p15.c (CARD_PRODUCT_RSCS): New.
(struct prkdf_object_s): Add fields is_ecc, token_label, and
tokenflags.
(do_deinit): Free new fields.
(cardproduct2str): New.
(read_ef_prkdf): Set new is_ecc flag.
(read_ef_tokeninfo): Store some data and move Tokeninfo diags to ...
(read_p15_info): here. set the product info here after all data has
been gathered.
(send_keypairinfo): Chnage the way the gpgusage flags are used.
(make_pin_prompt): If the token has a label and the current cert has
no CN, show the label as holder info.
(do_sign): Support ECDSA. Take care of the gpgusage flags.
(do_decipher): Support ECDH. Take care of the gpgusage flags.
--
This has been tested with Trusted Object Manager generated cards by
Rohde & Schwarz Cybersecurity.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/iso7816.c (CMD_SELECT_DATA): New.
(iso7816_select_data): New.
* scd/app-openpgp.c (do_readcert): Allow OpenPGP.1 and OPENPGP.2
(do_writecert): Ditto.
(do_setattr): Add CERT-1 and CERT-2.
--
This has been tested with a Zeitcontrol 3.4 card. A test with a
Yubikey 5 (firmware 5.2.6) claiming to support 3.4 failed.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-openpgp.c (struct app_local_s): s/extcap_v3/is_v3/.
s/max_certlen_3/max_certlen. Change users.
--
The extcap_v3 flag is set if the version is 3 or later and as such
does not only declare that the v3 extcap layout is used. Make this
clear by renaming.
Likewise for max_certlen_3.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-openpgp.c (struct app_local_s): Add new flag.
(get_cached_data): Force chace use if flag is set.
(app_select_openpgp): Avoid reading DO 6E multiple times.
--
The do not cache property of 6E was introduced so that we can change
for example key attributes without getting into with the cache.
However, for initial reading the cache makes a lot of sense and thus we
now use this hack to only temporary cache. A better strategy would be
to clear the cache when we change card data but that is more error
prone.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (prepare_verify_pin): Allow for PRKDF to be NULL.
(make_pin_prompt): Ditto.
(verify_pin): Ditto.
(do_check_pin): Allow using the Label to specify a PIN.
--
Note that a label may not work in all cases because we can't select
the protected object's EF first.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (parse_common_obj_attr): Map spaces in the lapel to
underscores.
(read_ef_aodf): Prettify printing of the type.
(do_getattr): New attribute CHV-LABEL
(do_learn_status): Emit CHV-LABEL.
(verify_pin): Distinguish the PIN prompts.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-openpgp.c (struct app_local_s): Add ecc.algo field.
(send_key_attr): Use ecc.algo field.
(ecc_read_pubkey): Use ecc.algo field.
(ecc_writekey): Ed448 means EdDSA.
(parse_algorithm_attribute): Set ecc.algo field from card.
Add checking for Ed25519 for ECC_FLAG_DJB_TWEAK flag.
--
There used to be a possible support of Ed25519 with ECDSA, (instead of
EdDSA). To distinguish key for Ed25519 for EdDSA, we use the
flag: (flags eddsa). Ed448 has no support for ECDSA and defaults to
EdDSA even if no such flag.
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/scdaemon.h (opt): Add field opcsc_shared.
* scd/scdaemon.c (opcscShared): New.
(opts): Add "--pcsc-shared".
(main): Set flag.
* scd/apdu.c (connect_pcsc_card): Use it.
(pcsc_get_status): Take flag in account.
* scd/app-openpgp.c (cache_pin): Bypass in shared mode.
(verify_chv2: Do not auto verify chv1 in shared mode.
* scd/app-piv.c (cache_pin): By pass caceh in shared mode.
--
This option should in general not be used. The patch tries to limit
bad effects but using shared mode is somewhat dangerous depending on
the other PC/SC users.
* scd/app-piv.c (app_select_piv): Allow for full AID.
--
It appears that SP-800-73-x is not too clear about the format of these
objects. Many current cards (such as the Yubikey 5 series) apparently
have only the PIX in DO 0x4F and only the RID in object 0x79/0x4F.
However, other cards as well as the PivApplet Javacard applet have the
full AID in 0x4F (which actually seems closer to what the standard
says). PivApplet also has the full AID in 0x79/0x4F, but this is
probably incorrect. (Here is a long discussion of the matter from an
OpenSC author:
https://github.com/arekinath/PivApplet/issues/43#issuecomment-772649709)
[Taken from a mail to gnupg-devel date 2021-02-03.]
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (struct gpgusage_flags_s): New.
(struct prkdf_object_s): Add field gpgusage.
(struct app_local_s): Add field any_gpgusage.
(dump_gpgusage_flags): New.
(read_p15_info): Parse athe gpgusage flags.
(do_getattr): Take care of the gpgusage flags.
--
This features allows to mark keys to be used for OpenPGP. This is
done by putting additional extended key infos into the certificate
stored on the cards. Only if any such extended key usage is detected
for a stored certificate this new mode chimes in.
This feature gives the card issuer a high flexibility on how to make
sure certain keys are used with OpenPGP.
* scd/app-p15.c (struct keyaccess_flags_s): New.
(struct prkdf_object_s): Add field accessflags.
(dump_keyusage_flags): New.
(dump_keyaccess_flags): New.
(parse_keyaccess_flags): New.
(parse_common_key_attr): Return access flags.
(read_ef_prkdf): Parse the access flags. Allow for ECkeys.
(read_ef_pukdf): Ditto. Use new functions for printing.
(read_p15_info): Use new fucntion for printing.
* scd/app-p15.c (struct cdf_object_s): Add fields authid, authidlen,
and label.
(struct prkdf_object_s): Add field label.
(struct aodf_object_s): Ditto.
(release_cdflist): Free new fields.
(release_prkdflist): Free new field.
(release_aodf_object): Ditto.
(parse_common_obj_attr): Return the label.
(read_ef_prkdf): Store the label.
(read_ef_pukdf): Ditto.
(read_ef_cdf): Use parse_common_obj_attr and store authid and label.
Print them im verbose mode.
(read_ef_aodf): Store the label and print it.
* scd/app-p15.c (select_and_read_binary): Allow to skip the select.
(select_and_read_record): Return the statusword. Silence error
message for SW_FILE_STRUCT.
(select_ef_by_path): Fix selection with a home_DF.
(read_first_record): Fallback to read_binary for CardOS and return
info about this.
(read_ef_prkdf): Use info from read_first_record to decide whether to
use record or binary mode.
(read_ef_pukdf): Ditto.
(read_ef_aodf): Ditto.
(read_ef_cdf): Ditto. New arg cdftype for diagnostics.
(read_p15_info): Pass cdftype.
* scd/apdu.h (SW_FILE_STRUCT): New.
* scd/apdu.c (apdu_strerror): Map that one to a string.
* scd/iso7816.c (map_sw): and to a gpg-error.
* scd/command.c (do_readkey): Make --info also work if a readkey
command is available.
* scd/app-p15.c (cdf_object_from_certid): Fix a but introduced with
the previous commit.
* scd/app-p15.c: Add a couple of oid constants.
(struct cdf_object_s): Replace fields image and imagelen by cert.
(struct prkdf_object_s): Add extusage flags
(send_keypairinfo): Use them.
(cdf_object_from_certid): Factor parts out to ...
(cdf_object_from_objid): new function.
(read_ef_prkdf): Move info printing to ...
(read_p15_info): here. Fill the extusage flags.
(readcert_by_cdf): Cache the ksba cert object instead of the binary
cert.
* scd/app.c (select_additional_application): Fix a log_debug call.
(scd_update_reader_status_file): Ditto.
--
This allows us to return only KEYPAIRINFO lines for keys we can
actually use.
* scd/app-p15.c (pukdf_object_t): New.
(struct app_local_s): Add field public_key_info.
(release_pukdflist): New.
(select_and_read_record): No diagnostic in case of not_found.
(read_first_record): New. Factored out from the read_ef_ fucntions.
(read_ef_pukdf): New. Basically a copy of read_ef_prkdf for now.
(read_p15_info): Also read the public keys.
(cardtype2str): New.
(read_ef_tokeninfo): Print a string with the cardtype.
* scd/app-p15.c: Include host2net.h.
(DEFAULT_HOME_DF): New.
(select_and_read_binary): Replace slot by app. Change callers. Use
select_ef_by_path.
(select_and_read_record): ditto.
(select_ef_by_path): Make use use the home_df.
(parse_certid): Adjust for always set home_df.
(print_tokeninfo_tokenflags): Ditto.
(app_select_p15): Take the home_df from the FCI returned by select.
--
This uses modern APDUs and always selectd starting at the PCKS-15 home
DF. We could have made this much simpler but the goal is to keep
support for older cards although we can't test that easily.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/iso7816.c (iso7816_select_path): Add arg from_cdf.
* scd/app-nks.c (do_readkey): Adjust for this change.
* scd/app-p15.c (CARD_TYPE_CARDOS_53): New.
(IS_CARDOS_5): New.
(card_atr_list): Add standard ATR for CardOS 5.3.
(select_and_read_binary): Remove the fallback to record read hack.
(select_and_read_record): New.
(select_ef_by_path): Rework and support CardOS feature.
(read_ef_prkdf): Use read record for CardOS.
(read_ef_cdf): Ditto.
(read_ef_aodf): Ditto. Also fix bug in the detection of other
unsupported attribute types.
(verify_pin): Use IS_CARDOS_5 macro.
(app_select_p15): Force direct method for CardOS.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-p15.c (read_ef_tokeninfo): Print the ATR in verbose mode.
--
It is convenient to see the ATR close to the other info,
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app-nks.c (do_sign): Handle plain SHA-3 digests and verify
encoding of ASN.1 encoded hashes.
--
This makes it possible to create CSRs for NetKey card keys which are
signed with SHA256 by default.
GnuPG-bug-id: 5184
* scd/ccid-driver.c (abort_cmd): Add INIT argument to support
synchronize until success, even ignoring timeout.
(bulk_in): Normal use case of abort_cmd.
(ccid_vendor_specific_init): Initial use case of abort_cmd.
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/app-nks.c (filelist): Use special value -1 for IDLM pubkeys.
(keygripstr_from_pk_file): Handle special value.
(do_readcert): Ditto.
(do_writecert): Ditto.
--
This allows to get information about the keys from the card. However
the do_readkey still requires a fallback to readcert. This does not
work because there are no certificates yet on the card. The fix is to
fully implement do_readkey.
* scd/apdu.c (apdu_strerror): Add missing status codes.
* scd/command.c (cmd_getinfo): New sub-command apdu_strerror.
--
This is quite handy for gpg-card's APDU command and avoids that we
need to duplicate the mapping table or put it into a shared file.
* scd/app.c (app_dump_state): Also print the refcount.
(maybe_switch_app): Make sure the app exists on the card.
--
When switching the current card and the card does not support the same
apps as the former, we now reset the app to the first one.
Testcase is to use a standard OpenPGP card and a P15 card.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/app.c (is_same_serialno): New.
(check_application_conflict): Use this.
(select_application): Ditto.
(app_switch_current_card): Ditto.
* scd/app-openpgp.c (check_keyidstr): Ignore the card version and also
compare case insensitive.
--
This is required because we change what we emit as serialno of OpenPGP
cards but existing keys still use the old form of the serial
number (i.e. with a firmware version).
See-commit: 3a8250c020
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/iso7816.c (iso7816_read_binary_ext): Add optional arg r_sw and
change callers.
(iso7816_read_record): Factor all code out to ...
(iso7816_read_record_ext): new.
* scd/app-p15.c (select_and_read_binary): Fallback to record reading.
(read_ef_aodf): Clear EOF error.
* scd/app.c (app_new_register): Call app_munge_serialno for Yubikeys.
(app_munge_serialno): Handle Yubikey serial numbers.
(card_get_serialno): Remove special Yubikey treatment. Drop arg
is_canonical.
(app_get_serialno): Clear ERRNO on error.
(card_get_dispserialno): New. Also change formatting of Yubikey and
OpenPGP numbers to match those printed on the card.
(app_get_dispserialno): New.
* scd/app-openpgp.c (do_getattr): Use app_get_dispserialno.
(yubikey_get_serialno): Remove.
* scd/app-piv.c (get_dispserialno): Remove.
(do_getattr): Use app_get_dispserialno.
--
This patch gets us back to a unique serial number for cards and
provides a stable serial number as printed for Yubikeys.
Because we use a slightly different serial number now for Yubikeys and
cards only supporting OpenPGP card we need to come up with another
change so that the version number of OpenPGP serial numbers are
ignored when comparing card serial numbers. This is so that existing
stub keys of gpg-agent will continue to work.
GnuPG-bug-id: 5100
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/command.c (reset_notify): Add option --keep-lock.
(do_reset): Add arg keep_lock.
(cmd_lock): Send progress status.
* g10/call-agent.c (agent_scd_apdu): Add more pseudo APDUs.
* g10/card-util.c (send_apdu): Ditto.
(factory_reset): Use lock commands.
--
This is required so that for example Kleopatra does not detect the
RESET and issues a SERIALNO of its own, thus conflicting with our
SERIALNO undefined.
Signed-off-by: Werner Koch <wk@gnupg.org>
* scd/apdu.c (apdu_send_direct): Use lock_slot.
--
With trylock_slot, it may return SW_HOST_BUSY. This may occur when
apdu_get_status is called by scd_update_reader_status_file.
Simply using lock_slot is much easier for user of apdu_send_direct.
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/ccid-driver.c (ccid_require_get_status): For VENDOR_SCM reader,
return 0 only at the initial call.
(bulk_in): Don't detect an error for VENDOR_SCM reader, just kicking
the loop, to invoke scd_update_reader_status_file, which calls
ccid_slot_status again.
(ccid_slot_status): Move the call of ccid_vendor_specific_setup to...
(ccid_get_atr): ... here.
--
For readers with interrupt transfer support, it is only intr_cb which
sets handle->powered_off to 1. Keeping this condition makes no race.
The function ccid_slot_status can also detect a communication error,
which causes apdu_close_reader (but not setting ->powered_off).
GnuPG-bug-id: 5121
Fixes-commit: 920f258eb6
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/app-piv.c (do_writecert): Flush the cache of the data object.
--
Suggested-by: Ingo Klöcker
GnuPG-bug-id: 5102
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* scd/ccid-driver.c (ccid_vendor_specific_setup): New. Limit
only for SPR532, excluding other readers by SCM.
(ccid_slot_status): Use ccid_vendor_specific_setup.
--
We follow the setup procedure of libccid implementation, which sends
the escape command for SPR532 only.
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
--
We need to use es_fopen on Windows to cope with non-ascii file names.
This is quite a large but fortunately straightforward change. At a
very few places we keep using stdio (for example due to the use of
popen).
GnuPG-bug-id: 5098
Signed-off-by: Werner Koch <wk@gnupg.org>
