1 files changed, 53 insertions, 0 deletions
diff --git a/lib/proto.h b/lib/proto.h
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+++ b/lib/proto.h
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+/*  Copyright (C) CZ.NIC, z.s.p.o. <knot-resolver@labs.nic.cz>
+ *  SPDX-License-Identifier: GPL-3.0-or-later
+ */
+#pragma once
+
+#include <stdint.h>
+
+#include "lib/defines.h"
+
+/** DNS transport protocol map
+ *
+ * This macro is used to generate `enum kr_proto` as well as other additional
+ * data on protocols, like name string constants.
+ *
+ * It defines DNS transport protocols for use by `session2` (to define sequences
+ * of protocol layers) and `rules` (to filter requests based on them). To find
+ * out more, see the individual usages.
+ *
+ * Parameters for XX are:
+ *   1. Constant name (for e.g. KR_PROTO_* enum value identifiers)
+ *   2. Variable name (for e.g. kr_proto_* array identifiers, like those defined
+ *      in `session2.c`)
+ *   3. Human-readable name for logging */
+#define KR_PROTO_MAP(XX) \
+    XX(UDP53, udp53, "DNS UDP") \
+    XX(TCP53, tcp53, "DNS TCP") \
+    XX(DOT, dot, "DNS-over-TLS") \
+    XX(DOH, doh, "DNS-over-HTTPS") \
+    XX(DOQ, doq, "DNS-over-QUIC") /* unused for now */ \
+    //
+
+/** DNS protocol set - mutually exclusive options, contrary to
+ * kr_request_qsource_flags
+ *
+ * The XDP flag is not discerned here, as it could apply to any protocol. (Not
+ * right now, but libknot does support it for TCP, so that would complete
+ * everything)
+ */
+enum kr_proto {
+	KR_PROTO_INTERNAL = 0, /// no protocol, e.g. useful to mark internal requests
+#define XX(cid, vid, name) KR_PROTO_ ## cid,
+	KR_PROTO_MAP(XX)
+#undef XX
+	KR_PROTO_COUNT,
+};
+
+/** Gets the constant string name of the specified transport protocol. */
+KR_EXPORT
+const char *kr_proto_name(enum kr_proto p);
+
+/** Bitmap of enum kr_proto options. */
+typedef uint8_t kr_proto_set;
+static_assert(sizeof(kr_proto_set) * 8 >= KR_PROTO_COUNT, "bad combination of type sizes");