Add backend.lisp and file-backend.lisp.

1 files changed, 35 insertions, 0 deletions

diff --git a/src/backend.lisp b/src/backend.lisp
new file mode 100644
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--- /dev/null
+++ b/src/backend.lisp
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+;; This file is part of eris-cl.
+;; Copyright (C) 2022 Piotr Szarmański
+
+;; eris-cl is free software: you can redistribute it and/or modify it under the
+;; terms of the GNU Lesser General Public License as published by the Free
+;; Software Foundation, either version 3 of the License, or (at your option) any
+;; later version.
+
+;; eris-cl 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
+;; eris-cl. If not, see <https://www.gnu.org/licenses/>.
+
+;; This file contains the backend protocol.
+(in-package :eris)
+
+(defclass encoding-backend ()
+  ((output-function :type function)))
+
+(defclass decoding-backend ()
+  ((fetch-function :type function)))
+
+(defgeneric fetch-read-capability (read-capability backend &key &allow-other-keys)
+  (:documentation
+   "Using the BACKEND, return a stream that decodes the provided READ-CAPABILITY
+object."))
+
+(defgeneric store-data (input backend &key secret &allow-other-keys)
+  (:documentation
+   "Using the BACKEND, store the INPUT, which is either a stream or an octet
+vector. An additional 32-byte octet-vector SECRET can be provided in order to
+protect the data from attacks against convergent encryption."))
+