* g10/getkey.c (get_pubkey_fromfile): Add optional arg r_keyblock.
* g10/pkclist.c (find_and_check_key): Also encrypt to RENC subkeys.
* g10/getkey.c (parse_key_usage): Make public.
* g10/misc.c (openpgp_pk_algo_usage): Take PUBKEY_USAGE_RENC in
account.
* g10/packet.h (PKT_public_key): Change pubkey_usage from byte to u16.
(PKT_user_id): Cosmetic fix: change help_key_usage from int to u16.
* g10/sig-check.c (check_signature_metadata_validity): Handle time
conflict for ADSKs.
--
GnuPG-bug-id: 6395
This patch handles ADSK keys and encrypts to them. It does not yet
allow the creation of them. We backport this from master early to get
this part of the code out into the field.
* g10/kbnode.c (new_kbnode2): New.
* g10/import.c (delete_inv_parts): New arg r_otherrevsigs to store
misplaced revocations.
(import_revoke_cert): Allow to pass an entire list.
(import_one): Import revocations found by delete_inv_parts.
--
It might be useful to distribute revocations of old keys along with
new keys. This is in particicualrr useful for WKD stored keys. This
patch allows to put unrelated standalone revocations into a key. For
example they can simply appended to a keyblock. Right now it is a bit
inaesthetic to see diagnostics about misplaced or bad revocation
signatures.
Backported-from-master: 7aaedfb10767c74f3e6868dd1563cbbf1282ab2f
* g10/build-packet.c (do_encrypted_aead): New.
(do_symkey_enc): Handle version 5.
(build_packet): Support the ENCRYPTED_AEAD packet.
* g10/cipher.c (MIN_PARTIAL_SIZE): Remove unused macro.
(AEAD_ENC_BUFFER_SIZE): New macro.
(my_iobuf_write): New.
(write_header): Rename to write_cfb_header. Adjust caller.
(set_ocb_nonce_and_ad): New.
(write_ocb_header): New.
(write_ocb_auth_tag): New.
(write_ocb_final_chunk): New.
(do_ocb_flush): New.
(do_ocb_free): New.
(cipher_filter_ocb): New.
* g10/filter.h (cipher_filter_context_t): Add fields for AEAD.
* g10/encrypt.c (encrypt_symmetric): For the use of a session key in
OCB mode.
(encrypt_seskey): Revamp to support OCB.
(use_aead): New.
(encrypt_simple): Support OCB.
(write_symkey_enc): Ditto.
(encrypt_crypt): Ditto.
(encrypt_filter): Handle OCB.
* g10/options.h (opt): Add field force_ocb.
* g10/gpg.c (oForceOCB): New.
(opts): New option "--force-ocb".
(main): Set force_ocb option.
* g10/gpgcompose.c (encrypt_seskey): New.
* g10/keygen.c (aead_available): New global var.
(keygen_set_std_prefs): Set AEAD feature by default in GNUPG mode. Add
parings of aead feature flag.
(keygen_get_std_prefs): Set aead flag.
(add_feature_aead): New.
(keygen_upd_std_prefs): Set OCB as preference if AEAD is enabled.
* g10/pkclist.c (select_aead_from_pklist): New.
(warn_missing_aead_from_pklist): New.
(select_mdc_from_pklist): Remove this unused function.
--
This extends the long available OCB and EAX decryption feature. Due
to the meanwhile expired patent on OCB there is no more reason for
using EAX. Thus we forcefully use OCB if the AEAD feature flag is set
on a key.
In GNUPG mode new keys are now created with the AEAD feature flag set.
Option --rfc4880 is one way to disable this.
GnuPG-bug-id: 6263
* g10/keydb.h (GETPASSWORD_FLAG_SYMDECRYPT): New.
(passphrase_to_dek_ext): Remove this obsolete prototype.
* g10/passphrase.c (passphrase_get): Add arg flags. Use new flag
value.
(passphrase_to_dek): Add arg flags and pass it on.
* g10/mainproc.c (proc_symkey_enc): Use new flag.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/getkey.c (get_pubkey_with_ldap_fallback): New.
* g10/trustdb.c (verify_own_keys): Use it.
(cherry picked from commit 100037ac0f558e8959fc065d4703c85c2962489e)
* g10/keydb.h (pref_hint): Change from union to struct and add field
'exact'. Adjust callers.
* g10/pkclist.c (algo_available): Take care of the exact hint.
* g10/sign.c (sign_file): Fix indentation. Rework the hash from
recipient prefs.
--
This fixes a encrypt+sign case like: One recipient key has SHA512 as
highest ranked hash preference but the the signing key is a 256 bit
curve. Because we don't want to use a truncated hash with ECDSA, we
need to have an exact match - this is in particular important for
smartcard which check that the hash matches the curves.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/import.c (read_key_from_file): Rename to ...
(read_key_from_file_or_buffer): this and add new parameters. Adjust
callers.
(import_included_key_block): New.
* g10/packet.h (PKT_signature): Add field flags.key_block.
* g10/parse-packet.c (parse_signature): Set that flags.
* g10/sig-check.c (check_signature2): Add parm forced_pk and change
all callers.
* g10/mainproc.c (do_check_sig): Ditto.
(check_sig_and_print): Try the included key block if no key is
available.
--
This is is the second part to support the new Key Block subpacket.
The idea is that after having received a signed mail, it is instantly
possible to reply encrypted - without the need for any centralized
infrastructure.
There is one case where this does not work: A signed mail is received
using a specified signer ID (e.g. using gpg --sender option) and the
key block with only that user ID is thus imported. The next time a
mail is received using the same key but with a different user ID; the
signatures checks out using the key imported the last time. However,
the new user id is not imported. Now when trying to reply to that
last mail, no key will be found. We need to see whether we can update
a key in such a case.
GnuPG-bug-id: 4856
Signed-off-by: Werner Koch <wk@gnupg.org>
Backported from master
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/getkey.c (akl_empty_or_only_local): New.
* g10/gpg.c (DEFAULT_AKL_LIST): New.
(main): Use it here.
(main) <aLocateExtKeys>: Set default AKL if none is set.
--
This better matches the expectations of the user. The used list in
this case is the default list ("local,wkd") with local ignored by the
command anyway.
GnuPG-bug-id: 4662
Signed-off-by: Werner Koch <wk@gnupg.org>
(cherry picked from commit d058d80ed0d5edeff6d85108054b1dfd45ddad7d)
* g10/gpg.c (aLocateExtKeys): New.
(opts): Add --locate-external-keys.
(main): Implement that.
* g10/getkey.c (get_pubkey_byname): Implement GET_PUBKEY_NO_LOCAL.
(get_best_pubkey_byname): Add arg 'mode' and pass on to
get_pubkey_byname. Change callers.
* g10/keylist.c (public_key_list): Add arg 'no_local'.
(locate_one): Ditto. Pass on to get_best_pubkey_byname.
--
This new command is a shortcut for
--auto-key-locate nodefault,clear,wkd,... --locate-key
and uses the default or configured AKL list but does so without local.
See also
GnuPG-bug-id: 4599
Signed-off-by: Werner Koch <wk@gnupg.org>
(cherry picked from commit d00c8024e58822e0623b3fad99248ce68a8b7725)
* g10/keydb.h (enum get_pubkey_modes): New.
* g10/getkey.c (get_pubkey_byname): Repalce no_akl by a mode arg and
change all callers.
--
This change prepares the implementation of GET_PUBKEY_NO_LOCAL.
Signed-off-by: Werner Koch <wk@gnupg.org>
(cherry picked from commit 9980f81da765f88a65604ab083563bf15ccdb425)
* g10/keydb.h (struct kbnode_struct): Replace unused field RECNO by
new field TAG.
* g10/kbnode.c (alloc_node): Change accordingly.
* g10/import.c (import_one): Add arg r_valid.
(sec_to_pub_keyblock): Set tags.
(resync_sec_with_pub_keyblock): New.
(import_secret_one): Change return code to gpg_error_t. Return an
error code if sec_to_pub_keyblock failed. Resync secret keyblock.
--
When importing an invalid secret key ring for example without key
binding signatures or no UIDs, gpg used to let gpg-agent store the
secret keys anyway. This is clearly a bug because the diagnostics
before claimed that for example the subkeys have been skipped.
Importing the secret key parameters then anyway is surprising in
particular because a gpg -k does not show the key. After importing
the public key the secret keys suddenly showed up.
This changes the behaviour of
GnuPG-bug-id: 4392
to me more consistent but is not a solution to the actual bug.
Caution: The ecc.scm test now fails because two of the sample keys
don't have binding signatures.
Signed-off-by: Werner Koch <wk@gnupg.org>
(cherry picked from commit f799e9728bcadb3d4148a47848c78c5647860ea4)
* g10/getkey.c (get_pubkey_for_sig): New.
(get_pubkeyblock_for_sig): New.
* g10/mainproc.c (issuer_fpr_raw): Give global scope.
(check_sig_and_print): Use get_pubkeyblock_for_sig.
* g10/pkclist.c (check_signatures_trust): Use get_pubkey_for_sig.
* g10/sig-check.c (check_signature2): Ditto.
(check_signature_over_key_or_uid): Ditto.
--
GnuPG-bug-id: 4046
The whole getkey stuff is still a mess with way to much duplication
and missing caching of already fetched data.
Signed-off-by: Werner Koch <wk@gnupg.org>
(cherry picked from commit f7526c7bc754acf68bde0b79c785e875a9365d60)
* g10/getkey.c (get_user_id_string): Add arg R_NOUID. Change call
callers.
(get_user_id): Add arg R_NOUID. Change call callers.
* g10/mainproc.c (issuer_fpr_string): Make global.
* g10/keylist.c (list_keyblock_colon): Print a '?' for a missing key
also in --list-mode. Print the "issuer fpr" field also if there is an
issuer fingerprint subpacket.
--
Scripts used to rely on the "User ID not found" string even in the
--with-colons listing. However, that is not a good idea because that
string is subject to translations etc. Now we have an explicit way of
telling that a key is missing. For example:
gpg --list-sigs --with-colons | \
awk -F: '$1=="sig" && $2=="?" {if($13){print $13}else{print $5}}'
Prints all keyids or fingerprint of signing keys for which we do not
have the key in our local keyring.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/keydb.h (IS_BACK_SIG): New.
* g10/sig-check.c: Re-indent and use macros.
--
This makes the code easier to understand.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/keydb.c (keydb_handle): New field 'keep_lock'.
(keydb_release): Clear that flag.
(keydb_lock): New function.
(unlock_all): Skip if KEEP_LOCK is set.
* g10/getkey.c (get_keyblock_byfprint_fast): Call keep_lock if
requested.
--
That change is straightforward. It helps to avoid the race condition
that another gpg process inserts a key while the first process is
between the search and the insert.
A similar change is due for gpgsm.
Note that the key edit operations may still suffer from a race.
GnuPG-bug-id: 3446
* g10/getkey.c (get_pubkey_byfprint_fast): Factor most code out to ...
(get_keyblock_byfprint_fast): .. new function.
* g10/import.c (revocation_present): s/int rc/gpg_error_t err/.
(import_one): Use get_keyblock_byfprint_fast to get the keyblock and a
handle. Remove the now surplus keyblock fetch in the merge branch.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/gpg.c (main): Add KEYSERVER_AUTO_KEY_RETRIEVE to the default
keyserver options. Set the default for --auto-key-locate to
"local,wkd". Reset that default iff --auto-key-locate has been given
in the option file or in the commandline.
* g10/getkey.c (parse_auto_key_locate): Work on a copy of the arg.
--
GnuPG-bug-id: 3324
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/getkey.c (get_best_pubkey_byname): Change return type to
gpg_error_t. Use var name err instead of rc. Move a
gpg_error_from_syserror closer to the call.
--
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/keydb.h (MK_DATESTR_SIZE): New.
* g10/keyid.c (mk_datestr): Make public. Add arg bufsize and use
snprintf. Change arg atime to u32.
(datestr_from_pk): Simplify.
(datestr_from_sig): Ditto.
(expirestr_from_pk): Ditto.
(expirestr_from_sig): Ditto.
(revokestr_from_pk): Ditto.
--
Note that this also reduces the size of the static buffers from 16 to
11 which is sufficient for the string. In the past we added the 5
extra bytes to cope for bugs in gmtime which is now handles by
snprintf.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/call-agent.c (warn_version_mismatch): Revert.
(start_agent): Suppress version mismatch if relevant.
* g10/getkey.c (get_seckey_default_or_card): New.
* g10/skclist.c (build_sk_list): Use get_seckey_default_or_card.
--
The change of 97a2394, which prefers available card than default key
specified is too strong.
Fixes-commit: 97a2394ecafaa6f58e4a1f70ecfd04408dc15606
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
* g10/keydb.h (KEYDB_HANDLE): Move typedef to ...
* g10/gpg.h: here.
(struct server_control_s): Add field 'cached_getkey_kdb'.
* g10/gpg.c (gpg_deinit_default_ctrl): Release that keydb handle.
* g10/getkey.c (getkey_end): Cache keydb handle.
(get_pubkey): Use cached keydb handle.
* kbx/keybox-search.c (keybox_search_reset): Use lseek instead of
closing the file.
--
Before this patch a "gpg --check-sigs" opened and closed the keybox
file for almost every signature check. By caching the keydb handle
and using lseek(2) this can be limited to just 2 times. This might
speed up things on Windows.
Signed-off-by: Werner Koch <wk@gnupg.org>
--
For proper operations as a server we need to avoid global variables.
Thus we need to pass the session state CTRL to most functions. Quite
a lot of changes but fortunately straightforward to do.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/parse-packet.c (parse_trust): Rename to ...
(parse_ring_trust): this. Change args and implement new ring trust
packet format.
(parse): Add special ring trust packet handling.
* g10/packet.h (PKT_user_id): New fields KEYUPDATE, UPDATEURL, and
KEYSRC.
(PKT_public_key): Ditto.
(RING_TRUST_SIG, RING_TRUST_KEY, RING_TRUST_UID): New consts.
(PKT_ring_trust): New.
(struct packet_struct): Remove member RING_TRUST.
(strcu parse_packet_ctx_s): Add field SKIP_META.
(init_parse_packet): Init SKIPT_META.
* g10/free-packet.c (release_public_key_parts): Free UDPATEURL.
(free_user_id): Ditto.
* g10/mainproc.c (list_node): Remove printing of non-documented "rtv"
lines.
* g10/build-packet.c (build_packet_and_meta): New.
(do_ring_trust): New.
* g10/export.c (write_keyblock_to_output): Use build_packet_and_meta
in backup mode.
(do_export_one_keyblock): Ditto.
* g10/import.c (read_block): Add arg WITH_META. Skip ring trust
packets if that ism not set.
(import): Call read_block WITH_META in restore mode.
* g10/keydb.h (KEYSRC_UNKNOWN, KEYSRC_FILE, KEYSRC_KS, KEYSRC_PREF_KS)
(KEYSRC_WKD, KEYSRC_WKD_SD, KEYSRC_DANE): New constants. They are not
yet used, though.
* g10/keydb.c (parse_keyblock_image): Allow ring trust packets.
(build_keyblock_image): Ditto. Use build_packet_and_meta.
* g10/keyring.c (keyring_get_keyblock): Remove specila treatment of
ring trust packets.
(write_keyblock): Use build_packet_and_meta. Remove special treatment
of ring trust packets and initialization of the signature caches.
--
This patch introduced the framework to store meta data for keys and
user ids in the keyrings/keyboxes. Ring trust packets are
implementation defined and have always been used in gpg to cache the
signature verification status.
Ring trust packets are only exported with the export option "backup"
and only imported with the import option "restore".
The new code uses a cleaner way to handle the ring trust packets: When
the parser reads a ring trust packet and the previously read packet
matches the type of that ring trust packet, the information is stored
in that previously read packet (signature, user id, or primary key)
and the next packet is read immediately. Thus only the parser sees
the ring trust packets. Ring trust packets are written by using the
new function build_packet_and_meta instead of build_packet. That
function writes a ring trust packet when the needed information is
available.
As a side-effect of this patch the signature status cache works again
and "gpg --check-sigs" is thus much faster.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/tofu.c (initdb): Add column effective_policy to the bindings
table.
(record_binding): New parameters effective_policy and set_conflict.
Save the effective policy. If SET_CONFLICT is set, then set conflict
according to CONFLICT. Otherwise, preserve the current value of
conflict. Update callers.
(get_trust): Don't compute the effective policy here...
(get_policy): ... do it here, if it was not cached. Take new
parameters, PK, the public key, and NOW, the time that the operation
started. Update callers.
(show_statistics): New parameter PK. Pass it to get_policy. Update
callers.
(tofu_notice_key_changed): New function.
* g10/gpgv.c (tofu_notice_key_changed): New stub.
* g10/import.c (import_revoke_cert): Take additional argument CTRL.
Pass it to keydb_update_keyblock.
* g10/keydb.c (keydb_update_keyblock): Take additional argument CTRL.
Update callers.
[USE_TOFU]: Call tofu_notice_key_changed.
* g10/test-stubs.c (tofu_notice_key_changed): New stub.
* tests/openpgp/tofu.scm: Assume that manually setting a binding's
policy to auto does not cause the tofu engine to forget about any
conflict.
--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
We now store the computed policy in the tofu DB (in the
effective_policy column of the bindings table) to avoid computing it
every time, which is expensive. Further, policy is never overridden
in case of a conflict. Instead, we detect a conflict if CONFLICT is
not empty.
This change is backwards compatible to existing DBs. The only minor
incompatibility is that unresolved conflicts won't be automatically
resolved in case we import a direct signature, or cross signatures.
* g10/getkey.c (struct pubkey_cmp_cookie): New type.
(key_is_ok, uid_is_ok, subkey_is_ok): New functions.
(pubkey_cmp): Likewise.
(get_best_pubkey_byname): Likewise.
* g10/keydb.h (get_best_pubkey_byname): New prototype.
* g10/keylist.c (locate_one): Use the new function.
* g10/pkclist.c (find_and_check_key): Likewise.
* tests/openpgp/Makefile.am (XTESTS): Add new test.
(TEST_FILES): Add new files.
* tests/openpgp/key-selection.scm: New file.
* tests/openpgp/key-selection/0.asc: Likewise.
* tests/openpgp/key-selection/1.asc: Likewise.
* tests/openpgp/key-selection/2.asc: Likewise.
* tests/openpgp/key-selection/3.asc: Likewise.
* tests/openpgp/key-selection/4.asc: Likewise.
--
When a name resembling a mail address is given to either --locate-keys
or --recipient, rank the search results and use only the most relevant
key.
This also lets us query which key will be used for encryption using
--locate-keys. However, note that --locate-keys may also return keys
incapable of encryption, though it will prefer keys that have an
encryption subkey.
GnuPG-bug-id: 2359
Signed-off-by: Justus Winter <justus@g10code.com>
* g10/passphrase.c (passphrase_get): Remove arg KEYID. Change arg
MODE to NOCACHE.
(passphrase_to_dek): Remove args KEYID and PUBKEY_ALGO. Split arg
MODE into CREATE and NOCACHE. Change all callers and adjust stubs.
(passphrase_clear_cache): Remove args KEYID and ALGO. They are not
used. Change caller.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/gpg.c (oRecipientFile, oHiddenRecipientFile): New.
(opts): Add options --recipient-file and --hidden-recipient-file.
(main): Implement them. Also remove duplicate code from similar
options.
* g10/keydb.h (PK_LIST_FROM_FILE): New.
(PK_LIST_SHIFT): Bump up.
* g10/pkclist.c (expand_group): Take care of PK_LIST_FROM_FILE.
(find_and_check_key): Add and implement arg FROM_FILE.
(build_pk_list): Pass new value for new arg.
* g10/getkey.c (get_pubkey_fromfile): New.
* g10/gpgv.c (read_key_from_file): New stub.
* g10/test-stubs.c (read_key_from_file): New stub.
* g10/server.c (cmd_recipient): Add flag --file.
* g10/import.c (read_key_from_file): New.
* tests/openpgp/defs.scm (key-file1): New.
(key-file2): New.
* tests/openpgp/setup.scm: Add their private keys and import the
key-file1.
* tests/openpgp/encrypt.scm: Add new test.
--
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/keydb.h (keyid_cmp): New function.
* g10/keyid.c (pk_keyid): New function.
(pk_main_keyid): New function.
(keyid_copy): New function.
(pk_keyid_str): New function.
* g10/packet.h (PKT_public_key): Update comments for main_keyid and
keyid.
--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
Before accessing pk->keyid, it is necessary to call keyid_from_pk (pk,
NULL) to ensure that pk->keyid is valid. Because it is easy to forget
to do this, these accessor functions take care of it.
* g10/keydb.h: Remove agent_open, agent_close declarations/
* g10/migrate.c: #include <unistd.h> for access()
--
agent_open() is only defined statically in common/simple-pw-query.c,
it is neither used nor referenced anywhere else. agent_close doesn't
exist anywhere. The removal of these declarations removes an
unecessary inclusion of libassuan.h.
migrate.c was relying on keydb.h -> libassuan.h -> unistd.h for the
declaration of access(), so we now handle that explicitly instead.
* g10/keyid.c (format_keyid): Return a char *, not a const char *. If
BUFFER is NULL, then set LEN to the static buffer's size.
--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
--
When using tags (e.g. GNU global) to navigate the source code it is
way easier to have the documentation close to the function we are
looking at. Having the documentation in the header file would require
an extra manual lookup to understand the function.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/getkey.c: Allow arg RET_KEYBLOCK to be NULL.
--
This change adds the expected behavior for the getkey_next function
to fix this NULL de-ref.
GnuPG-bug-id: 2212
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/keydb.h (struct pubkey): Rename to pubkey_s.
(pubkey_t): New. Change all struct pubkey_s to use this type.
* g10/getkey.c (get_pubkeys): Rename arg keys to r_keys.
--
It is common in GnuPG to use a suffix of _s for struct names. There
is no technical need for this (actually this pattern comes from pre
ANSI C compilers which had no separate namespaces) but it avoid
surprises when reading the code.
Adding the pubkey_t type is mainly to improve font locking by using
the common suffix _t for a typedefed type.
Signed-off-by: Werner Koch <wk@gnupg.org>
* g10/gpg.c (struct result): Move from here...
* g10/keydb.h (struct pubkey): ... to here. Update users.
* g10/gpg.c (check_user_ids): Move from here...
* g10/getkey.c (get_pubkeys): ... to here. Update users. Use
get_pubkey_byname to look up the keys (this also prunes invalid keys).
(pubkey_free): New function.
(pubkeys_free): New function.
* g10/gpg.c (main): Don't check for ambiguous key specifications.
--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
Regression-due-to: e8c53fc
This change not only moves the checks for ambiguous key specifications
from gpg.c to getkey.c, it also disables the checks. The old code was
too divorced from the actual key lookups and, as such, it reproduced
the logic. Unfortunately, the reproduction was a poor one: despite
fixing some inconsistencies (e.g., 10cca02), it still didn't deal with
group expansion or the auto key lookup functionality. Given the
amount of instability introduced by this change, we (Neal & Werner)
decided it is better to defer introducing this functionality until
2.3.
* g10/pkclist.c (build_pk_list): Remove parameter use, which is always
called set to PUBKEY_USAGE_ENC. Update callers.
--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
* g10/keydb.c (keydb_update_keyblock): Don't replace the record at the
current offset. After taking the lock, extract the fingerprint from
the keyblock, find it and then replace it.
--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
GnuPG-bug-id: 2193
Between locating the record to update and actually updating the
keyblock, it is possible that another process modifies the keyring,
which causes the update to corrupt the keyring. This is due to a time
of check to time of use bug. The fix is straightforward: both
operations must be done while holding the lock. This changes the
semantics of the function slightly, but no callers need to be
modified. Further, it now becomes impossible to replace key A with B;
this function will only ever update B.
