1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2008 5 * Swinburne University of Technology, Melbourne, Australia. 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 AUTHORS 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 AUTHORS 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 29 /* 30 * Alias_sctp forms part of the libalias kernel module to handle 31 * Network Address Translation (NAT) for the SCTP protocol. 32 * 33 * This software was developed by David A. Hayes 34 * with leadership and advice from Jason But 35 * 36 * The design is outlined in CAIA technical report number 080618A 37 * (D. Hayes and J. But, "Alias_sctp Version 0.1: SCTP NAT implementation in IPFW") 38 * 39 * Development is part of the CAIA SONATA project, 40 * proposed by Jason But and Grenville Armitage: 41 * http://caia.swin.edu.au/urp/sonata/ 42 * 43 * 44 * This project has been made possible in part by a grant from 45 * the Cisco University Research Program Fund at Community 46 * Foundation Silicon Valley. 47 * 48 */ 49 50 51 #ifndef _ALIAS_SCTP_H_ 52 #define _ALIAS_SCTP_H_ 53 54 #include <sys/param.h> 55 #ifdef _KERNEL 56 #include <sys/malloc.h> 57 #include <sys/module.h> 58 #include <sys/kernel.h> 59 #include <sys/proc.h> 60 #include <sys/uio.h> 61 #include <sys/socketvar.h> 62 #include <sys/syslog.h> 63 #endif // #ifdef _KERNEL 64 #include <sys/types.h> 65 66 #include <sys/queue.h> 67 #include <sys/types.h> 68 #include <sys/time.h> 69 70 #include <netinet/in_systm.h> 71 #include <netinet/in.h> 72 #include <netinet/ip.h> 73 74 /** 75 * These are defined in sctp_os_bsd.h, but it can't be included due to its local file 76 * inclusion, so I'm defining them here. 77 * 78 */ 79 #include <machine/cpufunc.h> 80 /* The packed define for 64 bit platforms */ 81 #ifndef SCTP_PACKED 82 #define SCTP_PACKED __attribute__((packed)) 83 #endif //#ifndef SCTP_PACKED 84 #ifndef SCTP_UNUSED 85 #define SCTP_UNUSED __attribute__((unused)) 86 #endif //#ifndef SCTP_UNUSED 87 88 #include <netinet/sctp.h> 89 //#include <netinet/sctp_os_bsd.h> --might be needed later for mbuf stuff 90 #include <netinet/sctp_header.h> 91 92 #ifndef _KERNEL 93 #include <stdlib.h> 94 #include <stdio.h> 95 #endif //#ifdef _KERNEL 96 97 #define LINK_SCTP IPPROTO_SCTP 98 99 #define SN_TO_LOCAL 0 /**< packet traveling from global to local */ 100 #define SN_TO_GLOBAL 1 /**< packet traveling from local to global */ 101 #define SN_TO_NODIR 99 /**< used where direction is not important */ 102 103 #define SN_NAT_PKT 0x0000 /**< Network Address Translate packet */ 104 #define SN_DROP_PKT 0x0001 /**< drop packet (don't forward it) */ 105 #define SN_PROCESSING_ERROR 0x0003 /**< Packet processing error */ 106 #define SN_REPLY_ABORT 0x0010 /**< Reply with ABORT to sender (don't forward it) */ 107 #define SN_SEND_ABORT 0x0020 /**< Send ABORT to destination */ 108 #define SN_TX_ABORT 0x0030 /**< mask for transmitting abort */ 109 #define SN_REFLECT_ERROR 0x0100 /**< Reply with ERROR to sender on OOTB packet Tbit set */ 110 #define SN_REPLY_ERROR 0x0200 /**< Reply with ERROR to sender on ASCONF clash */ 111 #define SN_TX_ERROR 0x0300 /**< mask for transmitting error */ 112 113 #define PKT_ALIAS_RESPOND 0x1000 /**< Signal to libalias that there is a response packet to send */ 114 /* 115 * Data structures 116 */ 117 118 /** 119 * @brief sctp association information 120 * 121 * Structure that contains information about a particular sctp association 122 * currently under Network Address Translation. 123 * Information is stored in network byte order (as is libalias)*** 124 */ 125 struct sctp_nat_assoc { 126 uint32_t l_vtag; /**< local side verification tag */ 127 uint16_t l_port; /**< local side port number */ 128 uint32_t g_vtag; /**< global side verification tag */ 129 uint16_t g_port; /**< global side port number */ 130 struct in_addr l_addr; /**< local ip address */ 131 struct in_addr a_addr; /**< alias ip address */ 132 int state; /**< current state of NAT association */ 133 int TableRegister; /**< stores which look up tables association is registered in */ 134 int exp; /**< timer expiration in seconds from uptime */ 135 int exp_loc; /**< current location in timer_Q */ 136 int num_Gaddr; /**< number of global IP addresses in the list */ 137 LIST_HEAD(sctpGlobalAddresshead,sctp_GlobalAddress) Gaddr; /**< List of global addresses */ 138 LIST_ENTRY (sctp_nat_assoc) list_L; /**< Linked list of pointers for Local table*/ 139 LIST_ENTRY (sctp_nat_assoc) list_G; /**< Linked list of pointers for Global table */ 140 LIST_ENTRY (sctp_nat_assoc) timer_Q; /**< Linked list of pointers for timer Q */ 141 //Using libalias locking 142 }; 143 144 struct sctp_GlobalAddress { 145 struct in_addr g_addr; 146 LIST_ENTRY (sctp_GlobalAddress) list_Gaddr; /**< Linked list of pointers for Global table */ 147 }; 148 149 /** 150 * @brief SCTP chunk of interest 151 * 152 * The only chunks whose contents are of any interest are the INIT and ASCONF_AddIP 153 */ 154 union sctpChunkOfInt { 155 struct sctp_init *Init; /**< Pointer to Init Chunk */ 156 struct sctp_init_ack *InitAck; /**< Pointer to Init Chunk */ 157 struct sctp_paramhdr *Asconf; /**< Pointer to ASCONF chunk */ 158 }; 159 160 /** 161 * @brief SCTP message 162 * 163 * Structure containing the relevant information from the SCTP message 164 */ 165 struct sctp_nat_msg { 166 uint16_t msg; /**< one of the key messages defined above */ 167 #ifdef INET6 168 // struct ip6_hdr *ip_hdr; /**< pointer to ip packet header */ /*no inet6 support yet*/ 169 #else 170 struct ip *ip_hdr; /**< pointer to ip packet header */ 171 #endif //#ifdef INET6 172 struct sctphdr *sctp_hdr; /**< pointer to sctp common header */ 173 union sctpChunkOfInt sctpchnk; /**< union of pointers to the chunk of interest */ 174 int chunk_length; /**< length of chunk of interest */ 175 }; 176 177 /** 178 * @brief sctp nat timer queue structure 179 * 180 */ 181 182 struct sctp_nat_timer { 183 int loc_time; /**< time in seconds for the current location in the queue */ 184 int cur_loc; /**< index of the current location in the circular queue */ 185 LIST_HEAD(sctpTimerQ,sctp_nat_assoc) *TimerQ; /**< List of associations at this position in the timer Q */ 186 }; 187 188 #endif //#ifndef _ALIAS_SCTP_H 189