In a simple program, for which a blocking operation is acceptable, the
following function can be used to retrieve a single key.
-@deftypefun GpgmeError gpgme_get_key (@w{GpgmeCtx @var{ctx}}, @w{const char *@var{fpr}}, @w{GpgmeKey *@var{r_key}}, @w{int @var{secret}}, @w{int @var{force_update}})
+@deftypefun GpgmeError gpgme_get_key (@w{GpgmeCtx @var{ctx}}, @w{const char *@var{fpr}}, @w{GpgmeKey *@var{r_key}}, @w{int @var{secret}})
The function @code{gpgme_get_key} gets the key with the fingerprint
-(or key ID) @var{fpr} from the key cache or from the crypto backend
-and return it in @var{r_key}. If @var{force_update} is true, force a
-refresh of the key from the crypto backend and replace the key in the
-cache, if any. If @var{secret} is true, get the secret key.
-
-If the @code{GPGME_KEYLIST_MODE_SIGS} mode is active, the key will be
-retrieved with the key signatures (and updated if necessary).
+(or key ID) @var{fpr} from the crypto backend and return it in
+@var{r_key}. If @var{force_update} is true, force a refresh of the
+key from the crypto backend and replace the key in the cache, if any.
+If @var{secret} is true, get the secret key. The currently active
+keylist mode is used to retrieve the key.
The function returns @code{GPGME_Invalid_Value} if @var{ctx} or
@var{r_key} is not a valid pointer, @code{GPGME_Invalid_Key} if
+++ /dev/null
-/* key-cache.c - Key cache routines.
- Copyright (C) 2000 Werner Koch (dd9jn)
- Copyright (C) 2001, 2002, 2003 g10 Code GmbH
-
- This file is part of GPGME.
-
- GPGME is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- GPGME is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GPGME; if not, write to the Free Software Foundation,
- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
-
-#if HAVE_CONFIG_H
-#include <config.h>
-#endif
-#include <stdlib.h>
-#include <string.h>
-
-#include "gpgme.h"
-#include "util.h"
-#include "ops.h"
-#include "sema.h"
-#include "key.h"
-
-#if SIZEOF_UNSIGNED_INT < 4
-#error unsigned int too short to be used as a hash value
-#endif
-
-#define KEY_CACHE_SIZE 503
-#define KEY_CACHE_MAX_CHAIN_LENGTH 10
-
-struct key_cache_item_s
-{
- struct key_cache_item_s *next;
- GpgmeKey key;
-};
-
-/* Protects key_cache and key_cache_unused_items. */
-DEFINE_STATIC_LOCK (key_cache_lock);
-static struct key_cache_item_s *key_cache[KEY_CACHE_SIZE];
-static struct key_cache_item_s *key_cache_unused_items;
-
-\f
-/* We use the first 4 digits to calculate the hash. */
-static int
-hash_key (const char *fpr, unsigned int *rhash)
-{
- unsigned int hash;
- int c;
-
- if (!fpr)
- return -1;
- if ((c = _gpgme_hextobyte (fpr)) == -1)
- return -1;
- hash = c;
- if ((c = _gpgme_hextobyte (fpr+2)) == -1)
- return -1;
- hash |= c << 8;
- if ((c = _gpgme_hextobyte (fpr+4)) == -1)
- return -1;
- hash |= c << 16;
- if ((c = _gpgme_hextobyte (fpr+6)) == -1)
- return -1;
- hash |= c << 24;
-
- *rhash = hash;
- return 0;
-}
-
-\f
-/* Acquire a reference to KEY and add it to the key cache. */
-void
-_gpgme_key_cache_add (GpgmeKey key)
-{
- struct subkey_s *k;
-
- LOCK (key_cache_lock);
- /* Put the key under each fingerprint into the cache. We use the
- first 4 digits to calculate the hash. */
- for (k = &key->keys; k; k = k->next)
- {
- size_t n;
- unsigned int hash;
- struct key_cache_item_s *item;
-
- if (hash_key (k->fingerprint, &hash))
- continue;
-
- hash %= KEY_CACHE_SIZE;
- for (item = key_cache[hash], n=0; item; item = item->next, n++)
- {
- struct subkey_s *k2;
- if (item->key == key)
- /* Already in cache. */
- break;
- /* Now do a deeper check. */
- for (k2 = &item->key->keys; k2; k2 = k2->next)
- {
- if (k2->fingerprint && !strcmp (k->fingerprint, k2->fingerprint))
- {
- /* Okay, replace it with the new copy. */
- gpgme_key_unref (item->key);
- item->key = key;
- gpgme_key_ref (item->key);
- UNLOCK (key_cache_lock);
- return;
- }
- }
- }
- if (item)
- continue;
-
- if (n > KEY_CACHE_MAX_CHAIN_LENGTH)
- {
- /* Remove the last entries. */
- struct key_cache_item_s *last = NULL;
-
- for (item = key_cache[hash];
- item && n < KEY_CACHE_MAX_CHAIN_LENGTH;
- last = item, item = item->next, n++)
- ;
-
- if (last)
- {
- struct key_cache_item_s *next;
-
- last->next = NULL;
- for (; item; item = next)
- {
- next = item->next;
- gpgme_key_unref (item->key);
- item->key = NULL;
- item->next = key_cache_unused_items;
- key_cache_unused_items = item;
- }
- }
- }
-
- item = key_cache_unused_items;
- if (item)
- {
- key_cache_unused_items = item->next;
- item->next = NULL;
- }
- else
- {
- item = malloc (sizeof *item);
- if (!item)
- {
- UNLOCK (key_cache_lock);
- return;
- }
- }
-
- item->key = key;
- gpgme_key_ref (key);
- item->next = key_cache[hash];
- key_cache[hash] = item;
- }
- UNLOCK (key_cache_lock);
-}
-
-
-GpgmeKey
-_gpgme_key_cache_get (const char *fpr)
-{
- struct key_cache_item_s *item;
- unsigned int hash;
-
- LOCK (key_cache_lock);
- if (hash_key (fpr, &hash))
- {
- UNLOCK (key_cache_lock);
- return NULL;
- }
-
- hash %= KEY_CACHE_SIZE;
- for (item = key_cache[hash]; item; item = item->next)
- {
- struct subkey_s *k;
-
- for (k = &item->key->keys; k; k = k->next)
- {
- if (k->fingerprint && !strcmp (k->fingerprint, fpr))
- {
- gpgme_key_ref (item->key);
- UNLOCK (key_cache_lock);
- return item->key;
- }
- }
- }
- UNLOCK (key_cache_lock);
- return NULL;
-}
-
-\f
-/* Get the key with the fingerprint FPR from the key cache or from the
- crypto backend. If FORCE_UPDATE is true, force a refresh of the
- key from the crypto backend and replace the key in the cache, if
- any. If SECRET is true, get the secret key. */
-GpgmeError
-gpgme_get_key (GpgmeCtx ctx, const char *fpr, GpgmeKey *r_key,
- int secret, int force_update)
-{
- GpgmeCtx listctx;
- GpgmeError err;
-
- if (!ctx || !r_key)
- return GPGME_Invalid_Value;
-
- if (strlen (fpr) < 16) /* We have at least a key ID. */
- return GPGME_Invalid_Key;
-
- if (!force_update)
- {
- *r_key = _gpgme_key_cache_get (fpr);
- if (*r_key)
- {
- /* If the primary UID (if available) has no signatures, and
- we are in the signature listing keylist mode, then try to
- update the key below before returning. */
- if (!((ctx->keylist_mode & GPGME_KEYLIST_MODE_SIGS)
- && (*r_key)->uids && !(*r_key)->uids->certsigs))
- return 0;
- }
- }
-
- /* We need our own context because we have to avoid the user's I/O
- callback handlers. */
- /* Fixme: This can be optimized by keeping an internal context
- used for such key listings. */
- err = gpgme_new (&listctx);
- if (err)
- return err;
- gpgme_set_protocol (listctx, gpgme_get_protocol (ctx));
- gpgme_set_keylist_mode (listctx, ctx->keylist_mode);
- err = gpgme_op_keylist_start (listctx, fpr, secret);
- if (!err)
- err = gpgme_op_keylist_next (listctx, r_key);
- gpgme_release (listctx);
- return err;
-}