usr.sbin/ppp/filter.h

   1 /*-
   2  * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
   3  *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
   4  *                           Internet Initiative Japan, Inc (IIJ)
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD: src/usr.sbin/ppp/filter.h,v 1.21.2.6 2002/09/01 02:12:27 brian Exp $
  29  * $DragonFly: src/usr.sbin/ppp/filter.h,v 1.2 2003/06/17 04:30:00 dillon Exp $
  30  */
  31
  32 /* Operations - f_srcop, f_dstop */
  33 #define OP_NONE 0
  34 #define OP_EQ   1
  35 #define OP_GT   2
  36 #define OP_LT   3
  37
  38 /* srctype or dsttype */
  39 #define T_ADDR          0
  40 #define T_MYADDR        1
  41 #define T_MYADDR6       2
  42 #define T_HISADDR       3
  43 #define T_HISADDR6      4
  44 #define T_DNS0          5
  45 #define T_DNS1          6
  46
  47 /*
  48  * There's a struct filterent for each possible filter rule.  The
  49  * layout is designed to minimise size (there are 4 * MAXFILTERS of
  50  * them) - which is also conveniently a power of 2 (32 bytes) on
  51  * architectures where sizeof(int)==4 (this makes indexing faster).
  52  *
  53  * Note that there are four free bits in the initial word for future
  54  * extensions.
  55  */
  56 struct filterent {
  57   int f_proto;                  /* Protocol: getprotoby*() */
  58   unsigned f_action : 8;        /* Filtering action: goto or A_... */
  59   unsigned f_srcop : 2;         /* Source port operation: OP_... */
  60   unsigned f_dstop : 2;         /* Destination port operation: OP_... */
  61   unsigned f_srctype : 3;       /* T_ value of src */
  62   unsigned f_dsttype : 3;       /* T_ value of dst */
  63   unsigned f_estab : 1;         /* Check TCP ACK bit */
  64   unsigned f_syn : 1;           /* Check TCP SYN bit */
  65   unsigned f_finrst : 1;        /* Check TCP FIN/RST bits */
  66   unsigned f_invert : 1;        /* true to complement match */
  67   struct ncprange f_src;        /* Source address and mask */
  68   struct ncprange f_dst;        /* Destination address and mask */
  69   u_short f_srcport;            /* Source port, compared with f_srcop */
  70   u_short f_dstport;            /* Destination port, compared with f_dstop */
  71   unsigned timeout;             /* Keep alive value for passed packet */
  72 };
  73
  74 #define MAXFILTERS      40      /* in each filter set */
  75
  76 /* f_action values [0..MAXFILTERS) specify the next filter rule, others are: */
  77 #define A_NONE          (MAXFILTERS)
  78 #define A_PERMIT        (A_NONE+1)
  79 #define A_DENY          (A_PERMIT+1)
  80
  81 struct filter {
  82   struct filterent rule[MAXFILTERS];    /* incoming packet filter */
  83   const char *name;
  84   unsigned fragok : 1;
  85   unsigned logok : 1;
  86 };
  87
  88 /* Which filter set */
  89 #define FL_IN           0
  90 #define FL_OUT          1
  91 #define FL_DIAL         2
  92 #define FL_KEEP         3
  93
  94 struct ipcp;
  95 struct cmdargs;
  96
  97 extern int filter_Show(struct cmdargs const *);
  98 extern int filter_Set(struct cmdargs const *);
  99 extern const char * filter_Action2Nam(int);
 100 extern const char *filter_Op2Nam(int);
 101 extern void filter_AdjustAddr(struct filter *, struct ncpaddr *,
 102                               struct ncpaddr *, struct in_addr *);