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