src/slirp/ip.h

/*
 * Copyright (c) 1982, 1986, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)ip.h        8.1 (Berkeley) 6/10/93
 * ip.h,v 1.3 1994/08/21 05:27:30 paul Exp
 */

#ifndef _IP_H_
#define _IP_H_

#ifdef WORDS_BIGENDIAN
# ifndef NTOHL
#  define NTOHL(d)
# endif
# ifndef NTOHS
#  define NTOHS(d)
# endif
# ifndef HTONL
#  define HTONL(d)
# endif
# ifndef HTONS
#  define HTONS(d)
# endif
#else
# ifndef NTOHL
#  define NTOHL(d) ((d) = ntohl((d)))
# endif
# ifndef NTOHS
#  define NTOHS(d) ((d) = ntohs((u_int16_t)(d)))
# endif
# ifndef HTONL
#  define HTONL(d) ((d) = htonl((d)))
# endif
# ifndef HTONS
#  define HTONS(d) ((d) = htons((u_int16_t)(d)))
# endif
#endif

typedef u_int32_t n_long;                 /* long as received from the net */

/*
 * Definitions for internet protocol version 4.
 * Per RFC 791, September 1981.
 */
#define IPVERSION       4

/*
 * Structure of an internet header, naked of options.
 *
 * We declare ip_len and ip_off to be short, rather than u_short
 * pragmatically since otherwise unsigned comparisons can result
 * against negative integers quite easily, and fail in subtle ways.
 */
#ifdef PRAGMA_PACK_SUPPORTED
#pragma pack(1)
#endif

struct ip {
#ifdef WORDS_BIGENDIAN
        u_int ip_v:4,                   /* version */
                ip_hl:4;                /* header length */
#else
        u_int ip_hl:4,          /* header length */
                ip_v:4;                 /* version */
#endif
        u_int8_t ip_tos;                        /* type of service */
        int16_t ip_len;                 /* total length */
        u_int16_t       ip_id;                  /* identification */
        int16_t ip_off;                 /* fragment offset field */
#define IP_DF 0x4000                    /* don't fragment flag */
#define IP_MF 0x2000                    /* more fragments flag */
#define IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
        u_int8_t ip_ttl;                        /* time to live */
        u_int8_t ip_p;                  /* protocol */
        u_int16_t       ip_sum;                 /* checksum */
        struct  in_addr ip_src,ip_dst;  /* source and dest address */
} PACKED__;

#ifdef PRAGMA_PACK_SUPPORTED
#pragma pack(0)
#endif

#define IP_MAXPACKET    65535           /* maximum packet size */

/*
 * Definitions for IP type of service (ip_tos)
 */
#define IPTOS_LOWDELAY          0x10
#define IPTOS_THROUGHPUT        0x08
#define IPTOS_RELIABILITY       0x04

/*
 * Definitions for options.
 */
#define IPOPT_COPIED(o)         ((o)&0x80)
#define IPOPT_CLASS(o)          ((o)&0x60)
#define IPOPT_NUMBER(o)         ((o)&0x1f)

#define IPOPT_CONTROL           0x00
#define IPOPT_RESERVED1         0x20
#define IPOPT_DEBMEAS           0x40
#define IPOPT_RESERVED2         0x60

#define IPOPT_EOL               0               /* end of option list */
#define IPOPT_NOP               1               /* no operation */

#define IPOPT_RR                7               /* record packet route */
#define IPOPT_TS                68              /* timestamp */
#define IPOPT_SECURITY          130             /* provide s,c,h,tcc */
#define IPOPT_LSRR              131             /* loose source route */
#define IPOPT_SATID             136             /* satnet id */
#define IPOPT_SSRR              137             /* strict source route */

/*
 * Offsets to fields in options other than EOL and NOP.
 */
#define IPOPT_OPTVAL            0               /* option ID */
#define IPOPT_OLEN              1               /* option length */
#define IPOPT_OFFSET            2               /* offset within option */
#define IPOPT_MINOFF            4               /* min value of above */

/*
 * Time stamp option structure.
 */
#ifdef PRAGMA_PACK_SUPPORTED
#pragma pack(1)
#endif

struct  ip_timestamp {
        u_int8_t        ipt_code;               /* IPOPT_TS */
        u_int8_t        ipt_len;                /* size of structure (variable) */
        u_int8_t        ipt_ptr;                /* index of current entry */
#ifdef WORDS_BIGENDIAN
        u_int   ipt_oflw:4,             /* overflow counter */
                ipt_flg:4;              /* flags, see below */
#else
        u_int   ipt_flg:4,              /* flags, see below */
                ipt_oflw:4;             /* overflow counter */
#endif
        union ipt_timestamp {
                n_long  ipt_time[1];
                struct  ipt_ta {
                        struct in_addr ipt_addr;
                        n_long ipt_time;
                } ipt_ta[1];
        } ipt_timestamp;
} PACKED__;

#ifdef PRAGMA_PACK_SUPPORTED
#pragma pack(0)
#endif

/* flag bits for ipt_flg */
#define IPOPT_TS_TSONLY         0               /* timestamps only */
#define IPOPT_TS_TSANDADDR      1               /* timestamps and addresses */
#define IPOPT_TS_PRESPEC        3               /* specified modules only */

/* bits for security (not byte swapped) */
#define IPOPT_SECUR_UNCLASS     0x0000
#define IPOPT_SECUR_CONFID      0xf135
#define IPOPT_SECUR_EFTO        0x789a
#define IPOPT_SECUR_MMMM        0xbc4d
#define IPOPT_SECUR_RESTR       0xaf13
#define IPOPT_SECUR_SECRET      0xd788
#define IPOPT_SECUR_TOPSECRET   0x6bc5

/*
 * Internet implementation parameters.
 */
#define MAXTTL          255             /* maximum time to live (seconds) */
#define IPDEFTTL        64              /* default ttl, from RFC 1340 */
#define IPFRAGTTL       60              /* time to live for frags, slowhz */
#define IPTTLDEC        1               /* subtracted when forwarding */

#define IP_MSS          576             /* default maximum segment size */

#ifdef HAVE_SYS_TYPES32_H  /* Overcome some Solaris 2.x junk */
#include <sys/types32.h>
#else
#if SIZEOF_CHAR_P == 4
typedef caddr_t caddr32_t;
#else
typedef u_int32_t caddr32_t;
#endif
#endif

#if SIZEOF_CHAR_P == 4
typedef struct ipq *ipqp_32;
typedef struct ipasfrag *ipasfragp_32;
#else
typedef caddr32_t ipqp_32;
typedef caddr32_t ipasfragp_32;
#endif

/*
 * Overlay for ip header used by other protocols (tcp, udp).
 */
#ifdef PRAGMA_PACK_SUPPORTED
#pragma pack(1)
#endif

struct ipovly {
        caddr32_t       ih_next, ih_prev;       /* for protocol sequence q's */
        u_int8_t        ih_x1;                  /* (unused) */
        u_int8_t        ih_pr;                  /* protocol */
        int16_t ih_len;                 /* protocol length */
        struct  in_addr ih_src;         /* source internet address */
        struct  in_addr ih_dst;         /* destination internet address */
} PACKED__;

#ifdef PRAGMA_PACK_SUPPORTED
#pragma pack(0)
#endif

/*
 * Ip reassembly queue structure.  Each fragment
 * being reassembled is attached to one of these structures.
 * They are timed out after ipq_ttl drops to 0, and may also
 * be reclaimed if memory becomes tight.
 * size 28 bytes
 */
struct ipq {
        ipqp_32 next,prev;      /* to other reass headers */
        u_int8_t        ipq_ttl;                /* time for reass q to live */
        u_int8_t        ipq_p;                  /* protocol of this fragment */
        u_int16_t       ipq_id;                 /* sequence id for reassembly */
        ipasfragp_32 ipq_next,ipq_prev;
                                        /* to ip headers of fragments */
        struct  in_addr ipq_src,ipq_dst;
};

/*
 * Ip header, when holding a fragment.
 *
 * Note: ipf_next must be at same offset as ipq_next above
 */
struct  ipasfrag {
#ifdef WORDS_BIGENDIAN
        u_int   ip_v:4,
                ip_hl:4;
#else
        u_int   ip_hl:4,
                ip_v:4;
#endif
                                        /* BUG : u_int changed to u_int8_t.
                                         * sizeof(u_int)==4 on linux 2.0
                                         */
        u_int8_t ipf_mff;               /* XXX overlays ip_tos: use low bit
                                         * to avoid destroying tos (PPPDTRuu);
                                         * copied from (ip_off&IP_MF) */
        int16_t ip_len;
        u_int16_t       ip_id;
        int16_t ip_off;
        u_int8_t        ip_ttl;
        u_int8_t        ip_p;
        u_int16_t       ip_sum;
        ipasfragp_32 ipf_next;          /* next fragment */
        ipasfragp_32 ipf_prev;          /* previous fragment */
};

/*
 * Structure stored in mbuf in inpcb.ip_options
 * and passed to ip_output when ip options are in use.
 * The actual length of the options (including ipopt_dst)
 * is in m_len.
 */
#define MAX_IPOPTLEN    40

struct ipoption {
        struct  in_addr ipopt_dst;      /* first-hop dst if source routed */
        int8_t  ipopt_list[MAX_IPOPTLEN];       /* options proper */
};

/*
 * Structure attached to inpcb.ip_moptions and
 * passed to ip_output when IP multicast options are in use.
 */

struct  ipstat {
        u_long  ips_total;              /* total packets received */
        u_long  ips_badsum;             /* checksum bad */
        u_long  ips_tooshort;           /* packet too short */
        u_long  ips_toosmall;           /* not enough data */
        u_long  ips_badhlen;            /* ip header length < data size */
        u_long  ips_badlen;             /* ip length < ip header length */
        u_long  ips_fragments;          /* fragments received */
        u_long  ips_fragdropped;        /* frags dropped (dups, out of space) */
        u_long  ips_fragtimeout;        /* fragments timed out */
        u_long  ips_forward;            /* packets forwarded */
        u_long  ips_cantforward;        /* packets rcvd for unreachable dest */
        u_long  ips_redirectsent;       /* packets forwarded on same net */
        u_long  ips_noproto;            /* unknown or unsupported protocol */
        u_long  ips_delivered;          /* datagrams delivered to upper level*/
        u_long  ips_localout;           /* total ip packets generated here */
        u_long  ips_odropped;           /* lost packets due to nobufs, etc. */
        u_long  ips_reassembled;        /* total packets reassembled ok */
        u_long  ips_fragmented;         /* datagrams successfully fragmented */
        u_long  ips_ofragments;         /* output fragments created */
        u_long  ips_cantfrag;           /* don't fragment flag was set, etc. */
        u_long  ips_badoptions;         /* error in option processing */
        u_long  ips_noroute;            /* packets discarded due to no route */
        u_long  ips_badvers;            /* ip version != 4 */
        u_long  ips_rawout;             /* total raw ip packets generated */
        u_long  ips_unaligned;          /* times the ip packet was not aligned */
};

extern struct   ipstat  ipstat;
extern struct   ipq     ipq;                    /* ip reass. queue */
extern u_int16_t        ip_id;                          /* ip packet ctr, for ids */
extern int      ip_defttl;                      /* default IP ttl */

#endif
Revision:	1.2
Committed:	2006-01-17T21:19:12Z (18 years, 5 months ago) by gbeauche
Content type:	text/plain
Branch:	MAIN
Changes since 1.1:	+27 -3 lines
Log Message:	Packet headers can be examined through unaligned addresses. This patch fixes this, especially for MIPS & SPARC platforms. [Initial patch from Brian J. Johnson]
#	User	Rev	Content
1	gbeauche	1.1	/*
2			* Copyright (c) 1982, 1986, 1993
3			* The Regents of the University of California. All rights reserved.
4			*
5			* Redistribution and use in source and binary forms, with or without
6			* modification, are permitted provided that the following conditions
7			* are met:
8			* 1. Redistributions of source code must retain the above copyright
9			* notice, this list of conditions and the following disclaimer.
10			* 2. Redistributions in binary form must reproduce the above copyright
11			* notice, this list of conditions and the following disclaimer in the
12			* documentation and/or other materials provided with the distribution.
13			* 3. All advertising materials mentioning features or use of this software
14			* must display the following acknowledgement:
15			* This product includes software developed by the University of
16			* California, Berkeley and its contributors.
17			* 4. Neither the name of the University nor the names of its contributors
18			* may be used to endorse or promote products derived from this software
19			* without specific prior written permission.
20			*
21			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31			* SUCH DAMAGE.
32			*
33			* @(#)ip.h 8.1 (Berkeley) 6/10/93
34			* ip.h,v 1.3 1994/08/21 05:27:30 paul Exp
35			*/
36
37			#ifndef _IP_H_
38			#define _IP_H_
39
40			#ifdef WORDS_BIGENDIAN
41			# ifndef NTOHL
42			# define NTOHL(d)
43			# endif
44			# ifndef NTOHS
45			# define NTOHS(d)
46			# endif
47			# ifndef HTONL
48			# define HTONL(d)
49			# endif
50			# ifndef HTONS
51			# define HTONS(d)
52			# endif
53			#else
54			# ifndef NTOHL
55			# define NTOHL(d) ((d) = ntohl((d)))
56			# endif
57			# ifndef NTOHS
58			# define NTOHS(d) ((d) = ntohs((u_int16_t)(d)))
59			# endif
60			# ifndef HTONL
61			# define HTONL(d) ((d) = htonl((d)))
62			# endif
63			# ifndef HTONS
64			# define HTONS(d) ((d) = htons((u_int16_t)(d)))
65			# endif
66			#endif
67
68			typedef u_int32_t n_long; /* long as received from the net */
69
70			/*
71			* Definitions for internet protocol version 4.
72			* Per RFC 791, September 1981.
73			*/
74			#define IPVERSION 4
75
76			/*
77			* Structure of an internet header, naked of options.
78			*
79			* We declare ip_len and ip_off to be short, rather than u_short
80			* pragmatically since otherwise unsigned comparisons can result
81			* against negative integers quite easily, and fail in subtle ways.
82			*/
83	gbeauche	1.2	#ifdef PRAGMA_PACK_SUPPORTED
84			#pragma pack(1)
85			#endif
86
87	gbeauche	1.1	struct ip {
88			#ifdef WORDS_BIGENDIAN
89			u_int ip_v:4, /* version */
90			ip_hl:4; /* header length */
91			#else
92			u_int ip_hl:4, /* header length */
93			ip_v:4; /* version */
94			#endif
95			u_int8_t ip_tos; /* type of service */
96			int16_t ip_len; /* total length */
97			u_int16_t ip_id; /* identification */
98			int16_t ip_off; /* fragment offset field */
99			#define IP_DF 0x4000 /* don't fragment flag */
100			#define IP_MF 0x2000 /* more fragments flag */
101			#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
102			u_int8_t ip_ttl; /* time to live */
103			u_int8_t ip_p; /* protocol */
104			u_int16_t ip_sum; /* checksum */
105			struct in_addr ip_src,ip_dst; /* source and dest address */
106	gbeauche	1.2	} PACKED__;
107
108			#ifdef PRAGMA_PACK_SUPPORTED
109			#pragma pack(0)
110			#endif
111	gbeauche	1.1
112			#define IP_MAXPACKET 65535 /* maximum packet size */
113
114			/*
115			* Definitions for IP type of service (ip_tos)
116			*/
117			#define IPTOS_LOWDELAY 0x10
118			#define IPTOS_THROUGHPUT 0x08
119			#define IPTOS_RELIABILITY 0x04
120
121			/*
122			* Definitions for options.
123			*/
124			#define IPOPT_COPIED(o) ((o)&0x80)
125			#define IPOPT_CLASS(o) ((o)&0x60)
126			#define IPOPT_NUMBER(o) ((o)&0x1f)
127
128			#define IPOPT_CONTROL 0x00
129			#define IPOPT_RESERVED1 0x20
130			#define IPOPT_DEBMEAS 0x40
131			#define IPOPT_RESERVED2 0x60
132
133			#define IPOPT_EOL 0 /* end of option list */
134			#define IPOPT_NOP 1 /* no operation */
135
136			#define IPOPT_RR 7 /* record packet route */
137			#define IPOPT_TS 68 /* timestamp */
138			#define IPOPT_SECURITY 130 /* provide s,c,h,tcc */
139			#define IPOPT_LSRR 131 /* loose source route */
140			#define IPOPT_SATID 136 /* satnet id */
141			#define IPOPT_SSRR 137 /* strict source route */
142
143			/*
144			* Offsets to fields in options other than EOL and NOP.
145			*/
146			#define IPOPT_OPTVAL 0 /* option ID */
147			#define IPOPT_OLEN 1 /* option length */
148			#define IPOPT_OFFSET 2 /* offset within option */
149			#define IPOPT_MINOFF 4 /* min value of above */
150
151			/*
152			* Time stamp option structure.
153			*/
154	gbeauche	1.2	#ifdef PRAGMA_PACK_SUPPORTED
155			#pragma pack(1)
156			#endif
157
158	gbeauche	1.1	struct ip_timestamp {
159			u_int8_t ipt_code; /* IPOPT_TS */
160			u_int8_t ipt_len; /* size of structure (variable) */
161			u_int8_t ipt_ptr; /* index of current entry */
162			#ifdef WORDS_BIGENDIAN
163			u_int ipt_oflw:4, /* overflow counter */
164			ipt_flg:4; /* flags, see below */
165			#else
166			u_int ipt_flg:4, /* flags, see below */
167			ipt_oflw:4; /* overflow counter */
168			#endif
169			union ipt_timestamp {
170			n_long ipt_time[1];
171			struct ipt_ta {
172			struct in_addr ipt_addr;
173			n_long ipt_time;
174			} ipt_ta[1];
175			} ipt_timestamp;
176	gbeauche	1.2	} PACKED__;
177
178			#ifdef PRAGMA_PACK_SUPPORTED
179			#pragma pack(0)
180			#endif
181	gbeauche	1.1
182			/* flag bits for ipt_flg */
183			#define IPOPT_TS_TSONLY 0 /* timestamps only */
184			#define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
185			#define IPOPT_TS_PRESPEC 3 /* specified modules only */
186
187			/* bits for security (not byte swapped) */
188			#define IPOPT_SECUR_UNCLASS 0x0000
189			#define IPOPT_SECUR_CONFID 0xf135
190			#define IPOPT_SECUR_EFTO 0x789a
191			#define IPOPT_SECUR_MMMM 0xbc4d
192			#define IPOPT_SECUR_RESTR 0xaf13
193			#define IPOPT_SECUR_SECRET 0xd788
194			#define IPOPT_SECUR_TOPSECRET 0x6bc5
195
196			/*
197			* Internet implementation parameters.
198			*/
199			#define MAXTTL 255 /* maximum time to live (seconds) */
200			#define IPDEFTTL 64 /* default ttl, from RFC 1340 */
201			#define IPFRAGTTL 60 /* time to live for frags, slowhz */
202			#define IPTTLDEC 1 /* subtracted when forwarding */
203
204			#define IP_MSS 576 /* default maximum segment size */
205
206			#ifdef HAVE_SYS_TYPES32_H /* Overcome some Solaris 2.x junk */
207			#include <sys/types32.h>
208			#else
209			#if SIZEOF_CHAR_P == 4
210			typedef caddr_t caddr32_t;
211			#else
212			typedef u_int32_t caddr32_t;
213			#endif
214			#endif
215
216			#if SIZEOF_CHAR_P == 4
217			typedef struct ipq *ipqp_32;
218			typedef struct ipasfrag *ipasfragp_32;
219			#else
220			typedef caddr32_t ipqp_32;
221			typedef caddr32_t ipasfragp_32;
222			#endif
223
224			/*
225			* Overlay for ip header used by other protocols (tcp, udp).
226			*/
227	gbeauche	1.2	#ifdef PRAGMA_PACK_SUPPORTED
228			#pragma pack(1)
229			#endif
230
231	gbeauche	1.1	struct ipovly {
232			caddr32_t ih_next, ih_prev; /* for protocol sequence q's */
233			u_int8_t ih_x1; /* (unused) */
234			u_int8_t ih_pr; /* protocol */
235			int16_t ih_len; /* protocol length */
236			struct in_addr ih_src; /* source internet address */
237			struct in_addr ih_dst; /* destination internet address */
238	gbeauche	1.2	} PACKED__;
239
240			#ifdef PRAGMA_PACK_SUPPORTED
241			#pragma pack(0)
242			#endif
243	gbeauche	1.1
244			/*
245			* Ip reassembly queue structure. Each fragment
246			* being reassembled is attached to one of these structures.
247			* They are timed out after ipq_ttl drops to 0, and may also
248			* be reclaimed if memory becomes tight.
249			* size 28 bytes
250			*/
251			struct ipq {
252			ipqp_32 next,prev; /* to other reass headers */
253			u_int8_t ipq_ttl; /* time for reass q to live */
254			u_int8_t ipq_p; /* protocol of this fragment */
255			u_int16_t ipq_id; /* sequence id for reassembly */
256			ipasfragp_32 ipq_next,ipq_prev;
257			/* to ip headers of fragments */
258			struct in_addr ipq_src,ipq_dst;
259			};
260
261			/*
262			* Ip header, when holding a fragment.
263			*
264			* Note: ipf_next must be at same offset as ipq_next above
265			*/
266			struct ipasfrag {
267			#ifdef WORDS_BIGENDIAN
268			u_int ip_v:4,
269			ip_hl:4;
270			#else
271			u_int ip_hl:4,
272			ip_v:4;
273			#endif
274			/* BUG : u_int changed to u_int8_t.
275			* sizeof(u_int)==4 on linux 2.0
276			*/
277			u_int8_t ipf_mff; /* XXX overlays ip_tos: use low bit
278			* to avoid destroying tos (PPPDTRuu);
279			* copied from (ip_off&IP_MF) */
280			int16_t ip_len;
281			u_int16_t ip_id;
282			int16_t ip_off;
283			u_int8_t ip_ttl;
284			u_int8_t ip_p;
285			u_int16_t ip_sum;
286			ipasfragp_32 ipf_next; /* next fragment */
287			ipasfragp_32 ipf_prev; /* previous fragment */
288			};
289
290			/*
291			* Structure stored in mbuf in inpcb.ip_options
292			* and passed to ip_output when ip options are in use.
293			* The actual length of the options (including ipopt_dst)
294			* is in m_len.
295			*/
296			#define MAX_IPOPTLEN 40
297
298			struct ipoption {
299			struct in_addr ipopt_dst; /* first-hop dst if source routed */
300			int8_t ipopt_list[MAX_IPOPTLEN]; /* options proper */
301			};
302
303			/*
304			* Structure attached to inpcb.ip_moptions and
305			* passed to ip_output when IP multicast options are in use.
306			*/
307
308			struct ipstat {
309			u_long ips_total; /* total packets received */
310			u_long ips_badsum; /* checksum bad */
311			u_long ips_tooshort; /* packet too short */
312			u_long ips_toosmall; /* not enough data */
313			u_long ips_badhlen; /* ip header length < data size */
314			u_long ips_badlen; /* ip length < ip header length */
315			u_long ips_fragments; /* fragments received */
316			u_long ips_fragdropped; /* frags dropped (dups, out of space) */
317			u_long ips_fragtimeout; /* fragments timed out */
318			u_long ips_forward; /* packets forwarded */
319			u_long ips_cantforward; /* packets rcvd for unreachable dest */
320			u_long ips_redirectsent; /* packets forwarded on same net */
321			u_long ips_noproto; /* unknown or unsupported protocol */
322			u_long ips_delivered; /* datagrams delivered to upper level*/
323			u_long ips_localout; /* total ip packets generated here */
324			u_long ips_odropped; /* lost packets due to nobufs, etc. */
325			u_long ips_reassembled; /* total packets reassembled ok */
326			u_long ips_fragmented; /* datagrams successfully fragmented */
327			u_long ips_ofragments; /* output fragments created */
328			u_long ips_cantfrag; /* don't fragment flag was set, etc. */
329			u_long ips_badoptions; /* error in option processing */
330			u_long ips_noroute; /* packets discarded due to no route */
331			u_long ips_badvers; /* ip version != 4 */
332			u_long ips_rawout; /* total raw ip packets generated */
333			u_long ips_unaligned; /* times the ip packet was not aligned */
334			};
335
336			extern struct ipstat ipstat;
337			extern struct ipq ipq; /* ip reass. queue */
338			extern u_int16_t ip_id; /* ip packet ctr, for ids */
339			extern int ip_defttl; /* default IP ttl */
340
341			#endif