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 */
125struct 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
144struct 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 */
154union 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 */
165struct 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
182struct 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