1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
5 *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
6 *                           Internet Initiative Japan, Inc (IIJ)
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD: stable/11/usr.sbin/ppp/filter.h 330449 2018-03-05 07:26:05Z eadler $
31 */
32
33/* Operations - f_srcop, f_dstop */
34#define	OP_NONE	0
35#define	OP_EQ	1
36#define	OP_GT	2
37#define	OP_LT	3
38
39/* srctype or dsttype */
40#define T_ADDR		0
41#define T_MYADDR	1
42#define T_MYADDR6	2
43#define T_HISADDR	3
44#define T_HISADDR6	4
45#define T_DNS0		5
46#define T_DNS1		6
47
48/*
49 * There's a struct filterent for each possible filter rule.  The
50 * layout is designed to minimise size (there are 4 * MAXFILTERS of
51 * them) - which is also conveniently a power of 2 (32 bytes) on
52 * architectures where sizeof(int)==4 (this makes indexing faster).
53 *
54 * Note that there are four free bits in the initial word for future
55 * extensions.
56 */
57struct filterent {
58  int f_proto;			/* Protocol: getprotoby*() */
59  unsigned f_action : 8;	/* Filtering action: goto or A_... */
60  unsigned f_srcop : 2;		/* Source port operation: OP_... */
61  unsigned f_dstop : 2;		/* Destination port operation: OP_... */
62  unsigned f_srctype : 3;	/* T_ value of src */
63  unsigned f_dsttype : 3;	/* T_ value of dst */
64  unsigned f_estab : 1;		/* Check TCP ACK bit */
65  unsigned f_syn : 1;		/* Check TCP SYN bit */
66  unsigned f_finrst : 1;	/* Check TCP FIN/RST bits */
67  unsigned f_invert : 1;	/* true to complement match */
68  struct ncprange f_src;	/* Source address and mask */
69  struct ncprange f_dst;	/* Destination address and mask */
70  u_short f_srcport;		/* Source port, compared with f_srcop */
71  u_short f_dstport;		/* Destination port, compared with f_dstop */
72  unsigned timeout;		/* Keep alive value for passed packet */
73};
74
75#define	MAXFILTERS	40	/* in each filter set */
76
77/* f_action values [0..MAXFILTERS) specify the next filter rule, others are: */
78#define	A_NONE		(MAXFILTERS)
79#define	A_PERMIT	(A_NONE+1)
80#define	A_DENY		(A_PERMIT+1)
81
82struct filter {
83  struct filterent rule[MAXFILTERS];	/* incoming packet filter */
84  const char *name;
85  unsigned fragok : 1;
86  unsigned logok : 1;
87};
88
89/* Which filter set */
90#define FL_IN		0
91#define FL_OUT		1
92#define FL_DIAL		2
93#define FL_KEEP		3
94
95struct ipcp;
96struct cmdargs;
97
98extern int filter_Show(struct cmdargs const *);
99extern int filter_Set(struct cmdargs const *);
100extern const char * filter_Action2Nam(unsigned);
101extern const char *filter_Op2Nam(unsigned);
102extern void filter_AdjustAddr(struct filter *, struct ncpaddr *,
103                              struct ncpaddr *, struct in_addr *);
104