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/*
* The author of this code is John Ioannidis, ji@tla.org,
* (except when noted otherwise).
*
* This code was written for BSD/OS in Athens, Greece, in November 1995.
*
* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
* by Angelos D. Keromytis, kermit@forthnet.gr.
*
* Copyright (C) 1995, 1996, 1997 by John Ioannidis and Angelos D. Keromytis.
*
* Permission to use, copy, and modify this software without fee
* is hereby granted, provided that this entire notice is included in
* all copies of any software which is or includes a copy or
* modification of this software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NEITHER AUTHOR MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
/*
* encap.h
*
* Declarations useful in the encapsulation code.
*/
/*
* Definitions for encapsulation-related phenomena.
*
* A lot of encapsulation protocols (ipip, swipe, ip_encap, ipsp, etc.)
* select their tunnel based on the destination (and sometimes the source)
* of the packet. The encap address/protocol family provides a generic
* mechanism for specifying tunnels.
*/
/*
* A tunnel is characterized by which source/destination address pairs
* (with netmasks) it is valid for (the "destination" as far as the
* routing code is concerned), and what the source (local) and destination
* (remote) endpoints of the tunnel, and the SPI, should be (the "gateway"
* as far as the routing code is concerned.
*/
struct sockaddr_encap
{
u_int8_t sen_len; /* length */
u_int8_t sen_family; /* AF_ENCAP */
u_int16_t sen_type; /* see SENT_* */
union
{
u_int8_t Data[16]; /* other stuff mapped here */
struct sockaddr Dfl; /* SENT_DEFIF */
struct /* SENT_SA */
{
struct sockaddr Src;
struct sockaddr Dst;
} Sa;
#ifdef INET
struct /* SENT_SAIN */
{
struct sockaddr_in Src;
struct sockaddr_in Dst;
} Sin;
struct /* SENT_IP4 */
{
struct in_addr Src;
struct in_addr Dst;
u_int16_t Sport;
u_int16_t Dport;
u_int8_t Proto;
u_int8_t Filler[3];
} Sip4;
struct /* SENT_IPSP */
{
struct in_addr Src;
struct in_addr Dst;
u_int32_t Spi;
u_int8_t Ifn;
u_int8_t Filler[3];
} Sipsp;
#endif
} Sen;
};
#define sen_data Sen.Data
#define sen_dfl Sen.Dfl
#define sen_sa_src Sen.Sa.Src
#define sen_sa_dst Sen.Sa.Dst
#ifdef INET
#define sen_sin_src Sen.Sin.Src
#define sen_sin_dst Sen.Sin.Dst
#define sen_ip_src Sen.Sip4.Src
#define sen_ip_dst Sen.Sip4.Dst
#define sen_ipsp_src Sen.Sipsp.Src
#define sen_ipsp_dst Sen.Sipsp.Dst
#define sen_ipsp_spi Sen.Sipsp.Spi
#define sen_ipsp_ifn Sen.Sipsp.Ifn
#define sen_proto Sen.Sip4.Proto
#define sen_sport Sen.Sip4.Sport
#define sen_dport Sen.Sip4.Dport
#endif
/*
* The "type" is really part of the address as far as the routing
* system is concerned. By using only one bit in the type field
* for each type, we sort-of make sure that different types of
* encapsulation addresses won't be matched against the wrong type.
*
*/
#define SENT_DEFIF 0x0001 /* data is a default sockaddr for if */
#define SENT_SA 0x0002 /* data is two struct sockaddr */
#define SENT_SAIN 0x0004 /* data is two struct sockaddr_in */
#define SENT_IP4 0x0008 /* data is two struct in_addr */
#define SENT_IPSP 0x0010 /* data as in IP4 plus SPI and if# */
/*
* SENT_HDRLEN is the length of the "header"
* SENT_*_LEN are the lengths of various forms of sen_data
* SENT_*_OFF are the offsets in the sen_data array of various fields
*/
#define SENT_HDRLEN (2*sizeof(u_int8_t)+sizeof(u_int16_t))
#define SENT_DEFIF_LEN (SENT_HDRLEN + sizeof (struct sockaddr_in))
#define SENT_IP4_SRCOFF (0)
#define SENT_IP4_DSTOFF (sizeof (struct in_addr))
#define SENT_IP4_OPTOFF (2*sizeof(struct in_addr)+2*sizeof(u_int16_t)+sizeof(u_int8_t)+3*sizeof(u_int8_t))
#define SENT_IP4_LEN (SENT_HDRLEN + SENT_IP4_OPTOFF)
#define SENT_IPSP_LEN (SENT_HDRLEN + 2 * sizeof (struct in_addr) + sizeof (u_int32_t) + 4)
/*
* Options 0x00 and 01 are 1-byte options (no arguments).
* The rest of the options are T-L-V fields, where the L includes
* the T and L bytes; thus, the minimum length for an option with
* no arguments is 2. An option of length less than 2 causes en EINVAL
*/
#define SENO_EOL 0x00 /* End of Options, or placeholder */
#define SENO_NOP 0x01 /* No Operation. Skip */
#define SENO_NAME 0x02 /* tunnel name, NUL-terminated */
#define SENO_SPI 0x03 /* Security Parameters Index */
#define SENO_IFN 0x04 /* Encap interface number */
#define SENO_IFIP4A 0x05 /* Encap interface IPv4 address */
#define SENO_IPSA 0x06 /* Encap interface generic sockaddr */
struct enc_softc
{
struct ifnet enc_if;
};
/*
* Tunnel descriptors are setup and torn down using a socket of the
* AF_ENCAP domain. The following defines the messages that can
* be sent down that socket.
*/
#define EM_MAXRELSPIS 4 /* at most five chained xforms */
struct encap_msghdr
{
u_int16_t em_msglen; /* message length */
u_int8_t em_version; /* for future expansion */
u_int8_t em_type; /* message type */
union
{
struct
{
struct in_addr Ia;
u_int8_t Ifn;
u_int8_t xxx[3]; /* makes life a lot easier */
} Ifa;
struct
{
u_int32_t Spi; /* SPI */
struct in_addr Dst; /* Destination address */
int32_t If; /* enc i/f for input */
int32_t Alg; /* Algorithm to use */
u_int8_t Dat[1]; /* Data */
} Xfm;
struct
{
u_int32_t emr_spi; /* SPI */
struct in_addr emr_dst; /* Dest */
struct tdb * emr_tdb; /* used internally! */
} Rel[EM_MAXRELSPIS];
} Eu;
};
#define em_ifa Eu.Ifa.Ia
#define em_ifn Eu.Ifa.Ifn
#define em_spi Eu.Xfm.Spi
#define em_dst Eu.Xfm.Dst
#define em_if Eu.Xfm.If
#define em_alg Eu.Xfm.Alg
#define em_dat Eu.Xfm.Dat
#define em_rel Eu.Rel
#define EMT_IFADDR 1 /* set enc if addr */
#define EMT_SETSPI 2 /* Set SPI properties */
#define EMT_GRPSPIS 3 /* Group SPIs (output order) */
#define EMT_DELSPI 4 /* delete an SPI */
#define EMT_DELSPICHAIN 5 /* delete an SPI chain starting from */
#define EM_MINLEN 8 /* count!!! */
#define EMT_IFADDR_LEN 12
#define EMT_SETSPI_FLEN 20
#define EMT_GRPSPIS_FLEN 4
#define EMT_DELSPI_FLEN 20
#define EMT_DELSPICHAIN_FLEN 20
#ifdef _KERNEL
extern struct ifaddr *encap_findgwifa(struct sockaddr *);
extern struct enc_softc *enc_softc;
extern int32_t nencap;
#endif
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