xref: /freebsd/sys/netinet/libalias/alias_sctp.h (revision 4e8d558c)
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 /* $FreeBSD$ */
51 
52 #ifndef _ALIAS_SCTP_H_
53 #define _ALIAS_SCTP_H_
54 
55 #include <sys/param.h>
56 #ifdef _KERNEL
57 #include <sys/malloc.h>
58 #include <sys/module.h>
59 #include <sys/kernel.h>
60 #include <sys/proc.h>
61 #include <sys/uio.h>
62 #include <sys/socketvar.h>
63 #include <sys/syslog.h>
64 #endif // #ifdef	_KERNEL
65 #include <sys/types.h>
66 
67 #include <sys/queue.h>
68 #include <sys/types.h>
69 #include <sys/time.h>
70 
71 #include <netinet/in_systm.h>
72 #include <netinet/in.h>
73 #include <netinet/ip.h>
74 
75 /**
76  * These are defined in sctp_os_bsd.h, but it can't be included due to its local file
77  * inclusion, so I'm defining them here.
78  *
79  */
80 #include <machine/cpufunc.h>
81 /* The packed define for 64 bit platforms */
82 #ifndef SCTP_PACKED
83 #define SCTP_PACKED __attribute__((packed))
84 #endif //#ifndef SCTP_PACKED
85 #ifndef SCTP_UNUSED
86 #define SCTP_UNUSED __attribute__((unused))
87 #endif //#ifndef SCTP_UNUSED
88 
89 #include <netinet/sctp.h>
90 //#include <netinet/sctp_os_bsd.h> --might be needed later for mbuf stuff
91 #include <netinet/sctp_header.h>
92 
93 #ifndef _KERNEL
94 #include <stdlib.h>
95 #include <stdio.h>
96 #endif //#ifdef _KERNEL
97 
98 #define LINK_SCTP                      IPPROTO_SCTP
99 
100 #define SN_TO_LOCAL              0   /**< packet traveling from global to local */
101 #define SN_TO_GLOBAL             1   /**< packet traveling from local to global */
102 #define SN_TO_NODIR             99   /**< used where direction is not important */
103 
104 #define SN_NAT_PKT          0x0000   /**< Network Address Translate packet */
105 #define SN_DROP_PKT         0x0001   /**< drop packet (don't forward it) */
106 #define SN_PROCESSING_ERROR 0x0003   /**< Packet processing error */
107 #define SN_REPLY_ABORT      0x0010   /**< Reply with ABORT to sender (don't forward it) */
108 #define SN_SEND_ABORT       0x0020   /**< Send ABORT to destination */
109 #define SN_TX_ABORT         0x0030   /**< mask for transmitting abort */
110 #define SN_REFLECT_ERROR    0x0100   /**< Reply with ERROR to sender on OOTB packet Tbit set */
111 #define SN_REPLY_ERROR      0x0200   /**< Reply with ERROR to sender on ASCONF clash */
112 #define SN_TX_ERROR         0x0300   /**< mask for transmitting error */
113 
114 #define PKT_ALIAS_RESPOND   0x1000   /**< Signal to libalias that there is a response packet to send */
115 /*
116  * Data structures
117  */
118 
119 /**
120  * @brief sctp association information
121  *
122  * Structure that contains information about a particular sctp association
123  * currently under Network Address Translation.
124  * Information is stored in network byte order (as is libalias)***
125  */
126 struct sctp_nat_assoc {
127 	uint32_t l_vtag;		/**< local side verification tag */
128 	uint16_t l_port;		/**< local side port number */
129 	uint32_t g_vtag;		/**< global side verification tag */
130 	uint16_t g_port;		/**< global side port number */
131 	struct in_addr l_addr;		/**< local ip address */
132 	struct in_addr a_addr;		/**< alias ip address */
133 	int state;			/**< current state of NAT association */
134 	int TableRegister;		/**< stores which look up tables association is registered in */
135 	int exp;			/**< timer expiration in seconds from uptime */
136 	int exp_loc;			/**< current location in timer_Q */
137 	int num_Gaddr;			/**< number of global IP addresses in the list */
138 	LIST_HEAD(sctpGlobalAddresshead,sctp_GlobalAddress) Gaddr; /**< List of global addresses */
139 	LIST_ENTRY (sctp_nat_assoc) list_L; /**< Linked list of pointers for Local table*/
140 	LIST_ENTRY (sctp_nat_assoc) list_G; /**< Linked list of pointers for Global table */
141 	LIST_ENTRY (sctp_nat_assoc) timer_Q; /**< Linked list of pointers for timer Q */
142 	//Using libalias locking
143 };
144 
145 struct sctp_GlobalAddress {
146 	struct in_addr g_addr;
147 	LIST_ENTRY (sctp_GlobalAddress) list_Gaddr; /**< Linked list of pointers for Global table */
148 };
149 
150 /**
151  * @brief SCTP chunk of interest
152  *
153  * The only chunks whose contents are of any interest are the INIT and ASCONF_AddIP
154  */
155 union sctpChunkOfInt {
156 	struct sctp_init *Init;		/**< Pointer to Init Chunk */
157 	struct sctp_init_ack *InitAck;	/**< Pointer to Init Chunk */
158 	struct sctp_paramhdr *Asconf;	/**< Pointer to ASCONF chunk */
159 };
160 
161 /**
162  * @brief SCTP message
163  *
164  * Structure containing the relevant information from the SCTP message
165  */
166 struct sctp_nat_msg {
167 	uint16_t msg;			/**< one of the key messages defined above */
168 #ifdef INET6
169 	//  struct ip6_hdr *ip_hdr;	/**< pointer to ip packet header */ /*no inet6 support yet*/
170 #else
171 	struct ip *ip_hdr;		/**< pointer to ip packet header */
172 #endif //#ifdef INET6
173 	struct sctphdr *sctp_hdr;	/**< pointer to sctp common header */
174 	union sctpChunkOfInt sctpchnk; /**< union of pointers to the chunk of interest */
175 	int chunk_length;		/**< length of chunk of interest */
176 };
177 
178 /**
179  * @brief sctp nat timer queue structure
180  *
181  */
182 
183 struct sctp_nat_timer {
184 	int loc_time;			/**< time in seconds for the current location in the queue */
185 	int cur_loc;			/**< index of the current location in the circular queue */
186 	LIST_HEAD(sctpTimerQ,sctp_nat_assoc) *TimerQ; /**< List of associations at this position in the timer Q */
187 };
188 
189 #endif //#ifndef _ALIAS_SCTP_H
190