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-rw-r--r--freebsd/contrib/tcpdump/print-vjc.c121
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diff --git a/freebsd/contrib/tcpdump/print-vjc.c b/freebsd/contrib/tcpdump/print-vjc.c
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+++ b/freebsd/contrib/tcpdump/print-vjc.c
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+#include <machine/rtems-bsd-user-space.h>
+
+/*
+ * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifndef lint
+static const char rcsid[] _U_ =
+ "@(#) $Header: /tcpdump/master/tcpdump/print-vjc.c,v 1.15 2004-03-25 03:31:17 mcr Exp $ (LBL)";
+#endif
+
+#include <tcpdump-stdinc.h>
+
+#include <pcap.h>
+#include <stdio.h>
+
+#include "interface.h"
+#include "addrtoname.h"
+
+#include "slcompress.h"
+#include "ppp.h"
+
+/*
+ * XXX - for BSD/OS PPP, what packets get supplied with a PPP header type
+ * of PPP_VJC and what packets get supplied with a PPP header type of
+ * PPP_VJNC? PPP_VJNC is for "UNCOMPRESSED_TCP" packets, and PPP_VJC
+ * is for COMPRESSED_TCP packets (PPP_IP is used for TYPE_IP packets).
+ *
+ * RFC 1144 implies that, on the wire, the packet type is *not* needed
+ * for PPP, as different PPP protocol types can be used; it only needs
+ * to be put on the wire for SLIP.
+ *
+ * It also indicates that, for compressed SLIP:
+ *
+ * If the COMPRESSED_TCP bit is set in the first byte, it's
+ * a COMPRESSED_TCP packet; that byte is the change byte, and
+ * the COMPRESSED_TCP bit, 0x80, isn't used in the change byte.
+ *
+ * If the upper 4 bits of the first byte are 7, it's an
+ * UNCOMPRESSED_TCP packet; that byte is the first byte of
+ * the UNCOMPRESSED_TCP modified IP header, with a connection
+ * number in the protocol field, and with the version field
+ * being 7, not 4.
+ *
+ * Otherwise, the packet is an IPv4 packet (where the upper 4 bits
+ * of the packet are 4).
+ *
+ * So this routine looks as if it's sort-of intended to handle
+ * compressed SLIP, although it doesn't handle UNCOMPRESSED_TCP
+ * correctly for that (it doesn't fix the version number and doesn't
+ * do anything to the protocol field), and doesn't check for COMPRESSED_TCP
+ * packets correctly for that (you only check the first bit - see
+ * B.1 in RFC 1144).
+ *
+ * But it's called for BSD/OS PPP, not SLIP - perhaps BSD/OS does weird
+ * things with the headers?
+ *
+ * Without a BSD/OS VJC-compressed PPP trace, or knowledge of what the
+ * BSD/OS VJC code does, we can't say what's the case.
+ *
+ * We therefore leave "proto" - which is the PPP protocol type - in place,
+ * *not* marked as unused, for now, so that GCC warnings about the
+ * unused argument remind us that we should fix this some day.
+ */
+int
+vjc_print(register const char *bp, u_short proto _U_)
+{
+ int i;
+
+ switch (bp[0] & 0xf0) {
+ case TYPE_IP:
+ if (eflag)
+ printf("(vjc type=IP) ");
+ return PPP_IP;
+ case TYPE_UNCOMPRESSED_TCP:
+ if (eflag)
+ printf("(vjc type=raw TCP) ");
+ return PPP_IP;
+ case TYPE_COMPRESSED_TCP:
+ if (eflag)
+ printf("(vjc type=compressed TCP) ");
+ for (i = 0; i < 8; i++) {
+ if (bp[1] & (0x80 >> i))
+ printf("%c", "?CI?SAWU"[i]);
+ }
+ if (bp[1])
+ printf(" ");
+ printf("C=0x%02x ", bp[2]);
+ printf("sum=0x%04x ", *(u_short *)&bp[3]);
+ return -1;
+ case TYPE_ERROR:
+ if (eflag)
+ printf("(vjc type=error) ");
+ return -1;
+ default:
+ if (eflag)
+ printf("(vjc type=0x%02x) ", bp[0] & 0xf0);
+ return -1;
+ }
+}