Initial import, still work in progress

1 files changed, 80 insertions, 0 deletions

diff --git a/llmnr-packet.h b/llmnr-packet.h
new file mode 100644
index 0000000..8b26bb9
--- /dev/null
+++ b/llmnr-packet.h
@@ -0,0 +1,80 @@
+/*
+ * LLMNR (RFC 4705) packet format definitions
+ *
+ * Copyright (C) 2015 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * This file is part of llmnrd.
+ *
+ * llmnrd 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, version 2 of the License.
+ *
+ * llmnrd 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 llmnrd.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef LLMNR_PACKET_H
+#define LLMNR_PACKET_H
+
+#include <stdint.h>
+
+#include "compiler.h"
+
+#define LLMNR_IPV4_MCAST_ADDR	"224.0.0.252"
+#define LLMNR_IPV6_MCAST_ADDR	"ff02:0:0:0:0:0:1:3"
+
+#define LLMNR_UDP_PORT		5355
+
+/*
+ * LLMNR packet header (RFC 4795, section 2.1.1)
+ */
+struct llmnr_hdr {
+	uint16_t id;
+	uint16_t flags;
+#define LLMNR_F_QR	0x8000
+#define LLMNR_F_OPCODE	0x7800
+#define LLMNR_F_C	0x0400
+#define LLMNR_F_TC	0x0200
+#define LLMNR_F_T	0x0100
+#define LLMNR_F_RCODE	0x000f
+	uint16_t qdcount;
+	uint16_t ancount;
+	uint16_t nscount;
+	uint16_t arcount;
+} __packed;
+
+/* Maximum label length according to RFC 1035 */
+#define LLMNR_LABEL_MAX_SIZE	63
+
+/* TYPE values according to RFC1035, section 3.2.2 */
+#define LLMNR_TYPE_A		1
+#define LLMNR_TYPE_NS		2
+#define LLMNR_TYPE_CNAME	5
+#define LLMNR_TYPE_SOA		6
+#define LLMNR_TYPE_PTR		12
+#define LLMNR_TYPE_HINFO	13
+#define LLMNR_TYPE_MINFO	14
+#define LLMNR_TYPE_MX		15
+#define LLMNR_TYPE_TXT		16
+#define LLMNR_TYPE_AAAA		28	/* RFC 3596 */
+
+/* QTYPE values according to RFC1035, section 3.2.3 */
+#define LLMNR_QTYPE_A		LLMNR_TYPE_A
+#define LLMNR_QTYPE_AAAA	LLMNR_TYPE_AAAA
+#define LLMNR_QTYPE_ANY		255
+
+/* CLASS values */
+#define LLMNR_CLASS_IN		1
+
+/* QCLASS values */
+#define LLMNR_QCLASS_IN		LLMNR_CLASS_IN
+
+/* Default RR TTL in seconds (RFC 4795, section 2.8) */
+#define LLMNR_TTL_DEFAULT	30
+
+#endif /* LLMNR_PACKET_H */