+ * Takes a list of keys and adds them to the database, merging them with
+ * the key in the database if it's already present there. The key list is
+ * update to contain the minimum set of updates required to get from what
+ * we had before to what we have now (ie the set of data that was added to
+ * the DB). Returns the number of entirely new keys added.
+ *
+ * If sendsync is true then we send out a keysync mail to our sync peers
+ * with the update.
+ */
+ int (*update_keys)(struct onak_dbctx *,
+ struct openpgp_publickey **keys,
+ struct keyarray *blacklist,
+ bool sendsync);
+
+/**
+ * @brief Takes a keyid and returns the primary UID for it.
+ * @param keyid The keyid to lookup.
+ *
+ * This function returns a UID for the given key. Returns NULL if the key
+ * isn't found.
+ */
+ char * (*keyid2uid)(struct onak_dbctx *, uint64_t keyid);
+
+/**
+ * @brief Gets a linked list of the signatures on a key.
+ * @param keyid The keyid to get the sigs for.
+ * @param revoked Is the key revoked?
+ *
+ * This function gets the list of signatures on a key. Used for key
+ * indexing and doing stats bits. If revoked is non-NULL then if the key
+ * is revoked it's set to true.
+ */
+ struct ll * (*getkeysigs)(struct onak_dbctx *,
+ uint64_t keyid, bool *revoked);
+
+/**
+ * @brief Gets the signatures on a key.
+ * @param keyid The key we want the signatures for.
+ *
+ * This function gets the signatures on a key. It's the same as the
+ * getkeysigs function above except we use the hash module to cache the
+ */
+ struct ll * (*cached_getkeysigs)(struct onak_dbctx *,
+ uint64_t keyid);
+
+/**
+ * @brief call a function once for each key in the db.
+ * @param iterfunc The function to call.
+ * @param ctx A context pointer
+ *
+ * Calls iterfunc once for each key in the database. ctx is passed
+ * unaltered to iterfunc. This function is intended to aid database dumps
+ * and statistic calculations.
+ *
+ * Returns the number of keys we iterated over.
+ */
+ int (*iterate_keys)(struct onak_dbctx *,
+ void (*iterfunc)(void *ctx,
+ struct openpgp_publickey *key), void *ctx);
+
+/**
+ * @brief Configuration file information for this backend instance
+ */
+ struct onak_db_config *config;
+
+/**
+ * @brief Private backend context information.