1 files changed, 97 insertions, 0 deletions
diff --git a/print-msdp.c b/print-msdp.c
new file mode 100644
index 0000000..7845116
--- /dev/null
+++ b/print-msdp.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2001 William C. Fenner.
+ *                All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that: (1) source code
+ * distributions retain the above copyright notice and this paragraph
+ * in its entirety, and (2) distributions including binary code include
+ * the above copyright notice and this paragraph in its entirety in
+ * the documentation or other materials provided with the distribution.
+ * The name of William C. Fenner may not be used to endorse or
+ * promote products derived from this software without specific prior
+ * written permission.  THIS SOFTWARE IS PROVIDED ``AS IS'' AND
+ * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
+ * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE.
+ */
+
+/* \summary: Multicast Source Discovery Protocol (MSDP) printer */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "netdissect-stdinc.h"
+
+#include "netdissect.h"
+#include "addrtoname.h"
+#include "extract.h"
+
+#define MSDP_TYPE_MAX	7
+
+void
+msdp_print(netdissect_options *ndo, const u_char *sp, u_int length)
+{
+	unsigned int type, len;
+
+	ndo->ndo_protocol = "msdp";
+	ND_PRINT(": ");
+	nd_print_protocol(ndo);
+	/* See if we think we're at the beginning of a compound packet */
+	type = GET_U_1(sp);
+	len = GET_BE_U_2(sp + 1);
+	if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX)
+		goto trunc;	/* not really truncated, but still not decodable */
+	while (length != 0) {
+		type = GET_U_1(sp);
+		len = GET_BE_U_2(sp + 1);
+		if (len > 1400 || ndo->ndo_vflag)
+			ND_PRINT(" [len %u]", len);
+		if (len < 3)
+			goto trunc;
+		if (length < len)
+			goto trunc;
+		sp += 3;
+		length -= 3;
+		switch (type) {
+		case 1:	/* IPv4 Source-Active */
+		case 3: /* IPv4 Source-Active Response */
+			if (type == 1)
+				ND_PRINT(" SA");
+			else
+				ND_PRINT(" SA-Response");
+			ND_PRINT(" %u entries", GET_U_1(sp));
+			if ((u_int)((GET_U_1(sp) * 12) + 8) < len) {
+				ND_PRINT(" [w/data]");
+				if (ndo->ndo_vflag > 1) {
+					ND_PRINT(" ");
+					ip_print(ndo, sp +
+						 GET_U_1(sp) * 12 + 8 - 3,
+						 len - (GET_U_1(sp) * 12 + 8));
+				}
+			}
+			break;
+		case 2:
+			ND_PRINT(" SA-Request");
+			ND_PRINT(" for %s", GET_IPADDR_STRING(sp + 1));
+			break;
+		case 4:
+			ND_PRINT(" Keepalive");
+			if (len != 3)
+				ND_PRINT("[len=%u] ", len);
+			break;
+		case 5:
+			ND_PRINT(" Notification");
+			break;
+		default:
+			ND_PRINT(" [type=%u len=%u]", type, len);
+			break;
+		}
+		sp += (len - 3);
+		length -= (len - 3);
+	}
+	return;
+trunc:
+	nd_print_trunc(ndo);
+}