1 files changed, 97 insertions, 0 deletions
diff --git a/src/libknot/cookies.h b/src/libknot/cookies.h
new file mode 100644
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+++ b/src/libknot/cookies.h
@@ -0,0 +1,97 @@
+/*  Copyright (C) 2017 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+    This program 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 3 of the License, or
+    (at your option) any later version.
+
+    This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+/*!
+* \file
+*
+* \brief DNS cookies processing.
+*
+* \addtogroup libknot
+* @{
+*/
+
+#pragma once
+
+#include <stdint.h>
+#include <sys/socket.h>
+
+#include "libknot/rrtype/opt.h"
+
+#define KNOT_EDNS_COOKIE_SECRET_SIZE 16
+
+/*!
+ * \brief DNS Cookie parameters needed to compute the cookie value.
+ *
+ * \note Server address is not used for the server cookie check.
+ */
+typedef struct {
+	const struct sockaddr *client_addr; /*!< Client socket address. */
+	const struct sockaddr *server_addr; /*!< Server socket address. */
+	uint8_t secret[KNOT_EDNS_COOKIE_SECRET_SIZE]; /*!< Cookie secret data. */
+} knot_edns_cookie_params_t;
+
+/*!
+ * \brief Generate a client cookie using given parameters.
+ *
+ * \param out     Generated client cookie.
+ * \param params  Client cookie parameters.
+ *
+ * \retval KNOT_EOK
+ * \retval KNOT_EINVAL
+ */
+int knot_edns_cookie_client_generate(knot_edns_cookie_t *out,
+                                     const knot_edns_cookie_params_t *params);
+
+/*!
+ * \brief Check whether client cookie was generated using given parameters.
+ *
+ * \param cc      Client cookie that should be checked.
+ * \param params  Client cookie parameters.
+ *
+ * \retval KNOT_EOK
+ * \retval KNOT_EINVAL
+ */
+int knot_edns_cookie_client_check(const knot_edns_cookie_t *cc,
+                                  const knot_edns_cookie_params_t *params);
+
+/*!
+ * \brief Generate a server cookie using given parameters.
+ *
+ * \param out     Generated server cookie.
+ * \param cc      Client cookie parameter.
+ * \param params  Server cookie parameters.
+ *
+ * \retval KNOT_EOK
+ * \retval KNOT_EINVAL
+ */
+int knot_edns_cookie_server_generate(knot_edns_cookie_t *out,
+                                     const knot_edns_cookie_t *cc,
+                                     const knot_edns_cookie_params_t *params);
+
+/*!
+ * \brief Check whether server cookie was generated using given parameters.
+ *
+ * \param sc      Server cookie that should be checked.
+ * \param cc      Client cookie parameter.
+ * \param params  Server cookie parameters.
+ *
+ * \retval KNOT_EOK
+ * \retval KNOT_EINVAL
+ */
+int knot_edns_cookie_server_check(const knot_edns_cookie_t *sc,
+                                  const knot_edns_cookie_t *cc,
+                                  const knot_edns_cookie_params_t *params);
+
+/*! @} */