include/uapi/linux/netfilter/xt_osf.h

   1 /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
   2 /*
   3  * Copyright (c) 2003+ Evgeniy Polyakov <johnpol@2ka.mxt.ru>
   4  *
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #ifndef _XT_OSF_H
  21 #define _XT_OSF_H
  22
  23 #include <linux/types.h>
  24 #include <linux/ip.h>
  25 #include <linux/tcp.h>
  26
  27 #define MAXGENRELEN             32
  28
  29 #define XT_OSF_GENRE            (1<<0)
  30 #define XT_OSF_TTL              (1<<1)
  31 #define XT_OSF_LOG              (1<<2)
  32 #define XT_OSF_INVERT           (1<<3)
  33
  34 #define XT_OSF_LOGLEVEL_ALL     0       /* log all matched fingerprints */
  35 #define XT_OSF_LOGLEVEL_FIRST   1       /* log only the first matced fingerprint */
  36 #define XT_OSF_LOGLEVEL_ALL_KNOWN       2 /* do not log unknown packets */
  37
  38 #define XT_OSF_TTL_TRUE         0       /* True ip and fingerprint TTL comparison */
  39 #define XT_OSF_TTL_LESS         1       /* Check if ip TTL is less than fingerprint one */
  40 #define XT_OSF_TTL_NOCHECK      2       /* Do not compare ip and fingerprint TTL at all */
  41
  42 struct xt_osf_info {
  43         char                    genre[MAXGENRELEN];
  44         __u32                   len;
  45         __u32                   flags;
  46         __u32                   loglevel;
  47         __u32                   ttl;
  48 };
  49
  50 /*
  51  * Wildcard MSS (kind of).
  52  * It is used to implement a state machine for the different wildcard values
  53  * of the MSS and window sizes.
  54  */
  55 struct xt_osf_wc {
  56         __u32                   wc;
  57         __u32                   val;
  58 };
  59
  60 /*
  61  * This struct represents IANA options
  62  * http://www.iana.org/assignments/tcp-parameters
  63  */
  64 struct xt_osf_opt {
  65         __u16                   kind, length;
  66         struct xt_osf_wc        wc;
  67 };
  68
  69 struct xt_osf_user_finger {
  70         struct xt_osf_wc        wss;
  71
  72         __u8                    ttl, df;
  73         __u16                   ss, mss;
  74         __u16                   opt_num;
  75
  76         char                    genre[MAXGENRELEN];
  77         char                    version[MAXGENRELEN];
  78         char                    subtype[MAXGENRELEN];
  79
  80         /* MAX_IPOPTLEN is maximum if all options are NOPs or EOLs */
  81         struct xt_osf_opt       opt[MAX_IPOPTLEN];
  82 };
  83
  84 struct xt_osf_nlmsg {
  85         struct xt_osf_user_finger       f;
  86         struct iphdr            ip;
  87         struct tcphdr           tcp;
  88 };
  89
  90 /* Defines for IANA option kinds */
  91
  92 enum iana_options {
  93         OSFOPT_EOL = 0,         /* End of options */
  94         OSFOPT_NOP,             /* NOP */
  95         OSFOPT_MSS,             /* Maximum segment size */
  96         OSFOPT_WSO,             /* Window scale option */
  97         OSFOPT_SACKP,           /* SACK permitted */
  98         OSFOPT_SACK,            /* SACK */
  99         OSFOPT_ECHO,
 100         OSFOPT_ECHOREPLY,
 101         OSFOPT_TS,              /* Timestamp option */
 102         OSFOPT_POCP,            /* Partial Order Connection Permitted */
 103         OSFOPT_POSP,            /* Partial Order Service Profile */
 104
 105         /* Others are not used in the current OSF */
 106         OSFOPT_EMPTY = 255,
 107 };
 108
 109 /*
 110  * Initial window size option state machine: multiple of mss, mtu or
 111  * plain numeric value. Can also be made as plain numeric value which
 112  * is not a multiple of specified value.
 113  */
 114 enum xt_osf_window_size_options {
 115         OSF_WSS_PLAIN   = 0,
 116         OSF_WSS_MSS,
 117         OSF_WSS_MTU,
 118         OSF_WSS_MODULO,
 119         OSF_WSS_MAX,
 120 };
 121
 122 /*
 123  * Add/remove fingerprint from the kernel.
 124  */
 125 enum xt_osf_msg_types {
 126         OSF_MSG_ADD,
 127         OSF_MSG_REMOVE,
 128         OSF_MSG_MAX,
 129 };
 130
 131 enum xt_osf_attr_type {
 132         OSF_ATTR_UNSPEC,
 133         OSF_ATTR_FINGER,
 134         OSF_ATTR_MAX,
 135 };
 136
 137 #endif                          /* _XT_OSF_H */