code for ISAKMP protocol headers (rough)
diff --git a/print-isakmp.c b/print-isakmp.c
new file mode 100644
index 0000000..9a6a0d4
--- /dev/null
+++ b/print-isakmp.c
@@ -0,0 +1,135 @@
+/* $NetBSD: print-ntp.c,v 1.3 1997/03/15 18:37:55 is Exp $ */
+
+/*
+ * Copyright (c) 1990, 1991, 1992, 1993, 1994
+ * The Regents of the University of California. 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, (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, and (3) all advertising materials mentioning
+ * features or use of this software display the following acknowledgement:
+ * ``This product includes software developed by the University of California,
+ * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
+ * the University nor the names of its contributors may 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.
+ *
+ * Format and print ntp packets.
+ * By Jeffrey Mogul/DECWRL
+ * loosely based on print-bootp.c
+ */
+
+#ifndef lint
+static char rcsid[] =
+ "@(#) Header: print-ntp.c,v 1.14 94/06/14 20:18:46 leres Exp (LBL)";
+#endif
+
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <net/if.h>
+
+#include <netinet/in.h>
+#ifdef __NetBSD__
+#include <net/if_ether.h>
+#else
+#include <netinet/if_ether.h>
+#endif
+
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "interface.h"
+#include "addrtoname.h"
+#undef MODEMASK /* Solaris sucks */
+#include "ntp.h"
+
+struct isakmp_header {
+ u_char init_cookie[4];
+ u_char resp_cookie[4];
+ u_char nextpayload;
+#if BYTE_ORDER == LITTLE_ENDIAN
+ u_char mnver:4;
+ u_char mjver:4;
+#endif
+#if BYTE_ORDER == BIG_ENDIAN
+ u_char mjver:4;
+ u_char mnver:4;
+#endif
+ u_char exgtype;
+ u_char flags;
+ u_char msgid[4];
+ u_int32 length;
+};
+
+#define FLAGS_ENCRYPTION 1
+#define FLAGS_COMMIT 2
+
+/*
+ * Print isakmp requests
+ */
+void
+isakmp_print(register const u_char *cp, int length)
+{
+ struct isakmp_header *ih;
+ register const u_char *ep;
+ int mode, version, leapind;
+
+#define TCHECK(var, l) if ((u_char *)&(var) > ep - l) goto trunc
+
+ ih = (struct isakmp_header *)cp;
+ /* Note funny sized packets */
+ if (length < 20)
+ {
+ (void)printf(" [len=%d]", length);
+ }
+
+ /* 'ep' points to the end of avaible data. */
+ ep = snapend;
+
+ printf(" isakmp");
+
+ printf(" v%d.%d\n\t", ih->mjver, ih->mnver);
+
+ if(ih->flags & FLAGS_ENCRYPTION)
+ {
+ printf(" encrypted");
+ }
+
+ if(ih->flags & FLAGS_COMMIT)
+ {
+ printf(" commit");
+ }
+
+ printf(" from:%02x%02x%02x%02x to: %02x%02x%02x%02x",
+ ih->init_cookie[0], ih->init_cookie[1],
+ ih->init_cookie[2], ih->init_cookie[3],
+ ih->resp_cookie[0], ih->resp_cookie[1],
+ ih->resp_cookie[2], ih->resp_cookie[3]);
+
+ TCHECK(ih->msgid, sizeof(ih->msgid));
+ printf(" msgid:%02x%02x%02x%02x",
+ ih->msgid[0], ih->msgid[1],
+ ih->msgid[2], ih->msgid[3]);
+
+ TCHECK(ih->length, sizeof(ih->length));
+ printf(" length %d", ntohl(ih->length));
+
+ if(ih->mjver > 1)
+ {
+ printf(" new version");
+ return;
+ }
+
+trunc:
+ fputs(" [|isakmp]", stdout);
+}
