implement routine to download meta data and decrypt to libanastasis; improve API to include timestamp

1 files changed, 64 insertions, 3 deletions

diff --git a/src/include/anastasis.h b/src/include/anastasis.h
index b957f18..92c0745 100644
--- a/src/include/anastasis.h
+++ b/src/include/anastasis.h
@@ -374,6 +374,67 @@ ANASTASIS_challenge_abort (struct ANASTASIS_Challenge *c);
 
 
 /**
+ * Handle for an operation to get available recovery
+ * document versions.
+ */
+struct ANASTASIS_VersionCheck;
+
+
+/**
+ * Callback which passes back meta data about one of the
+ * recovery documents available at the provider.
+ *
+ * @param cls closure for the callback
+ * @param version version number of the policy document,
+ *                0 for the end of the list
+ * @param server_time time of the backup at the provider
+ * @param recdoc_id hash of the compressed recovery document, uniquely
+ *                  identifies the document; NULL for the end of the list
+ * @param secret_name name of the secret as chosen by the user,
+ *                  or NULL if the user did not provide a name
+ */
+typedef void
+(*ANASTASIS_MetaPolicyCallback)(void *cls,
+                                uint32_t version,
+                                struct GNUNET_TIME_Timestamp server_time,
+                                const struct GNUNET_HashCode *recdoc_id,
+                                const char *secret_name);
+
+
+/**
+ * Obtain an overview of available recovery policies from the
+ * specified provider.
+ *
+ * @param ctx context for making HTTP requests
+ * @param id_data contains the users identity, (user account on providers)
+ * @param version defines the version which will be downloaded, 0 for latest version
+ * @param anastasis_provider_url provider url
+ * @param provider_salt the server salt
+ * @param mpc function called with the available versions
+ * @param mpc_cls closure for @a mpc callback
+ * @return recovery operation handle
+ */
+struct ANASTASIS_VersionCheck *
+ANASTASIS_recovery_get_versions (
+  struct GNUNET_CURL_Context *ctx,
+  const json_t *id_data,
+  unsigned int max_version,
+  const char *anastasis_provider_url,
+  const struct ANASTASIS_CRYPTO_ProviderSaltP *provider_salt,
+  ANASTASIS_MetaPolicyCallback mpc,
+  void *mpc_cls);
+
+
+/**
+ * Cancel version check operation.
+ *
+ * @param vc operation to cancel
+ */
+void
+ANASTASIS_recovery_get_versions_cancel (struct ANASTASIS_VersionCheck *vc);
+
+
+/**
  * Defines a Decryption Policy with multiple escrow methods
  */
 struct ANASTASIS_DecryptionPolicy
@@ -528,9 +589,9 @@ struct ANASTASIS_Recovery;
  *
  * @param ctx context for making HTTP requests
  * @param id_data contains the users identity, (user account on providers)
- * @param version defines the version which will be downloaded NULL for latest version
- * @param anastasis_provider_url NULL terminated list of possible provider urls
- * @param provider_salt the server salt
+ * @param version defines the version which will be downloaded, 0 for latest version
+ * @param anastasis_provider_url provider REST API endpoint url
+ * @param provider_salt the provider's salt
  * @param pc opens the policy call back which holds the downloaded version and the policies
  * @param pc_cls closure for callback
  * @param csc core secret callback is opened, with this the core secert is passed to the client after the authentication