xref: /freebsd/sys/netinet/in.h (revision 0de89efe5c443f213c7ea28773ef2dc6cf3af2ed)
1 /*
2  * Copyright (c) 1982, 1986, 1990, 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  *	@(#)in.h	8.3 (Berkeley) 1/3/94
34  * $Id: in.h,v 1.26 1997/02/22 09:41:28 peter Exp $
35  */
36 
37 #ifndef _NETINET_IN_H_
38 #define _NETINET_IN_H_
39 
40 /*
41  * Constants and structures defined by the internet system,
42  * Per RFC 790, September 1981, and numerous additions.
43  */
44 
45 /*
46  * Protocols
47  */
48 #define	IPPROTO_IP		0		/* dummy for IP */
49 #define	IPPROTO_ICMP		1		/* control message protocol */
50 #define	IPPROTO_IGMP		2		/* group mgmt protocol */
51 #define	IPPROTO_GGP		3		/* gateway^2 (deprecated) */
52 #define IPPROTO_IPIP		4 		/* IP encapsulation in IP */
53 #define	IPPROTO_TCP		6		/* tcp */
54 #define	IPPROTO_EGP		8		/* exterior gateway protocol */
55 #define	IPPROTO_PUP		12		/* pup */
56 #define	IPPROTO_UDP		17		/* user datagram protocol */
57 #define	IPPROTO_IDP		22		/* xns idp */
58 #define	IPPROTO_TP		29 		/* tp-4 w/ class negotiation */
59 #define IPPROTO_RSVP		46 		/* resource reservation */
60 #define	IPPROTO_EON		80		/* ISO cnlp */
61 #define	IPPROTO_ENCAP		98		/* encapsulation header */
62 
63 #define	IPPROTO_DIVERT		254		/* divert pseudo-protocol */
64 #define	IPPROTO_RAW		255		/* raw IP packet */
65 #define	IPPROTO_MAX		256
66 
67 
68 /*
69  * Local port number conventions:
70  *
71  * When a user does a bind(2) or connect(2) with a port number of zero,
72  * a non-conflicting local port address is chosen.
73  * The default range is IPPORT_RESERVED through
74  * IPPORT_USERRESERVED, although that is settable by sysctl.
75  *
76  * A user may set the IPPROTO_IP option IP_PORTRANGE to change this
77  * default assignment range.
78  *
79  * The value IP_PORTRANGE_DEFAULT causes the default behavior.
80  *
81  * The value IP_PORTRANGE_HIGH changes the range of candidate port numbers
82  * into the "high" range.  These are reserved for client outbound connections
83  * which do not want to be filtered by any firewalls.
84  *
85  * The value IP_PORTRANGE_LOW changes the range to the "low" are
86  * that is (by convention) restricted to privileged processes.  This
87  * convention is based on "vouchsafe" principles only.  It is only secure
88  * if you trust the remote host to restrict these ports.
89  *
90  * The default range of ports and the high range can be changed by
91  * sysctl(3).  (net.inet.ip.port{hi,low}{first,last}_auto)
92  *
93  * Changing those values has bad security implications if you are
94  * using a a stateless firewall that is allowing packets outside of that
95  * range in order to allow transparent outgoing connections.
96  *
97  * Such a firewall configuration will generally depend on the use of these
98  * default values.  If you change them, you may find your Security
99  * Administrator looking for you with a heavy object.
100  */
101 
102 /*
103  * Ports < IPPORT_RESERVED are reserved for
104  * privileged processes (e.g. root).         (IP_PORTRANGE_LOW)
105  * Ports > IPPORT_USERRESERVED are reserved
106  * for servers, not necessarily privileged.  (IP_PORTRANGE_DEFAULT)
107  */
108 #define	IPPORT_RESERVED		1024
109 #define	IPPORT_USERRESERVED	5000
110 
111 /*
112  * Default local port range to use by setting IP_PORTRANGE_HIGH
113  */
114 #define	IPPORT_HIFIRSTAUTO	40000
115 #define	IPPORT_HILASTAUTO	44999
116 
117 /*
118  * Scanning for a free reserved port return a value below IPPORT_RESERVED,
119  * but higher than IPPORT_RESERVEDSTART.  Traditionally the start value was
120  * 512, but that conflicts with some well-known-services that firewalls may
121  * have a fit if we use.
122  */
123 #define IPPORT_RESERVEDSTART	600
124 
125 /*
126  * Internet address (a structure for historical reasons)
127  */
128 struct in_addr {
129 	u_long s_addr;
130 };
131 
132 /*
133  * Definitions of bits in internet address integers.
134  * On subnets, the decomposition of addresses to host and net parts
135  * is done according to subnet mask, not the masks here.
136  */
137 #define	IN_CLASSA(i)		(((long)(i) & 0x80000000) == 0)
138 #define	IN_CLASSA_NET		0xff000000
139 #define	IN_CLASSA_NSHIFT	24
140 #define	IN_CLASSA_HOST		0x00ffffff
141 #define	IN_CLASSA_MAX		128
142 
143 #define	IN_CLASSB(i)		(((long)(i) & 0xc0000000) == 0x80000000)
144 #define	IN_CLASSB_NET		0xffff0000
145 #define	IN_CLASSB_NSHIFT	16
146 #define	IN_CLASSB_HOST		0x0000ffff
147 #define	IN_CLASSB_MAX		65536
148 
149 #define	IN_CLASSC(i)		(((long)(i) & 0xe0000000) == 0xc0000000)
150 #define	IN_CLASSC_NET		0xffffff00
151 #define	IN_CLASSC_NSHIFT	8
152 #define	IN_CLASSC_HOST		0x000000ff
153 
154 #define	IN_CLASSD(i)		(((long)(i) & 0xf0000000) == 0xe0000000)
155 #define	IN_CLASSD_NET		0xf0000000	/* These ones aren't really */
156 #define	IN_CLASSD_NSHIFT	28		/* net and host fields, but */
157 #define	IN_CLASSD_HOST		0x0fffffff	/* routing needn't know.    */
158 #define	IN_MULTICAST(i)		IN_CLASSD(i)
159 
160 #define	IN_EXPERIMENTAL(i)	(((long)(i) & 0xf0000000) == 0xf0000000)
161 #define	IN_BADCLASS(i)		(((long)(i) & 0xf0000000) == 0xf0000000)
162 
163 #define	INADDR_ANY		(u_long)0x00000000
164 #define	INADDR_LOOPBACK		(u_long)0x7f000001
165 #define	INADDR_BROADCAST	(u_long)0xffffffff	/* must be masked */
166 #ifndef KERNEL
167 #define	INADDR_NONE		0xffffffff		/* -1 return */
168 #endif
169 
170 #define	INADDR_UNSPEC_GROUP	(u_long)0xe0000000	/* 224.0.0.0 */
171 #define	INADDR_ALLHOSTS_GROUP	(u_long)0xe0000001	/* 224.0.0.1 */
172 #define	INADDR_ALLRTRS_GROUP	(u_long)0xe0000002	/* 224.0.0.2 */
173 #define	INADDR_MAX_LOCAL_GROUP	(u_long)0xe00000ff	/* 224.0.0.255 */
174 
175 #define	IN_LOOPBACKNET		127			/* official! */
176 
177 /*
178  * Socket address, internet style.
179  */
180 struct sockaddr_in {
181 	u_char	sin_len;
182 	u_char	sin_family;
183 	u_short	sin_port;
184 	struct	in_addr sin_addr;
185 	char	sin_zero[8];
186 };
187 
188 /*
189  * Structure used to describe IP options.
190  * Used to store options internally, to pass them to a process,
191  * or to restore options retrieved earlier.
192  * The ip_dst is used for the first-hop gateway when using a source route
193  * (this gets put into the header proper).
194  */
195 struct ip_opts {
196 	struct	in_addr ip_dst;		/* first hop, 0 w/o src rt */
197 	char	ip_opts[40];		/* actually variable in size */
198 };
199 
200 /*
201  * Options for use with [gs]etsockopt at the IP level.
202  * First word of comment is data type; bool is stored in int.
203  */
204 #define	IP_OPTIONS		1    /* buf/ip_opts; set/get IP options */
205 #define	IP_HDRINCL		2    /* int; header is included with data */
206 #define	IP_TOS			3    /* int; IP type of service and preced. */
207 #define	IP_TTL			4    /* int; IP time to live */
208 #define	IP_RECVOPTS		5    /* bool; receive all IP opts w/dgram */
209 #define	IP_RECVRETOPTS		6    /* bool; receive IP opts for response */
210 #define	IP_RECVDSTADDR		7    /* bool; receive IP dst addr w/dgram */
211 #define	IP_RETOPTS		8    /* ip_opts; set/get IP options */
212 #define	IP_MULTICAST_IF		9    /* u_char; set/get IP multicast i/f  */
213 #define	IP_MULTICAST_TTL	10   /* u_char; set/get IP multicast ttl */
214 #define	IP_MULTICAST_LOOP	11   /* u_char; set/get IP multicast loopback */
215 #define	IP_ADD_MEMBERSHIP	12   /* ip_mreq; add an IP group membership */
216 #define	IP_DROP_MEMBERSHIP	13   /* ip_mreq; drop an IP group membership */
217 #define IP_MULTICAST_VIF	14   /* set/get IP mcast virt. iface */
218 #define IP_RSVP_ON		15   /* enable RSVP in kernel */
219 #define IP_RSVP_OFF		16   /* disable RSVP in kernel */
220 #define IP_RSVP_VIF_ON		17   /* set RSVP per-vif socket */
221 #define IP_RSVP_VIF_OFF		18   /* unset RSVP per-vif socket */
222 #define IP_PORTRANGE		19   /* int; range to choose for unspec port */
223 #define	IP_RECVIF		20   /* bool; receive reception if w/dgram */
224 
225 #define IP_FW_ADD     		50   /* add a firewall rule to chain */
226 #define IP_FW_DEL    		51   /* delete a firewall rule from chain */
227 #define IP_FW_FLUSH   		52   /* flush firewall rule chain */
228 #define IP_FW_ZERO    		53   /* clear single/all firewall counter(s) */
229 #define IP_FW_GET     		54   /* get entire firewall rule chain */
230 #define IP_NAT			55   /* set/get NAT opts */
231 
232 /*
233  * Defaults and limits for options
234  */
235 #define	IP_DEFAULT_MULTICAST_TTL  1	/* normally limit m'casts to 1 hop  */
236 #define	IP_DEFAULT_MULTICAST_LOOP 1	/* normally hear sends if a member  */
237 #define	IP_MAX_MEMBERSHIPS	20	/* per socket */
238 
239 /*
240  * Argument structure for IP_ADD_MEMBERSHIP and IP_DROP_MEMBERSHIP.
241  */
242 struct ip_mreq {
243 	struct	in_addr imr_multiaddr;	/* IP multicast address of group */
244 	struct	in_addr imr_interface;	/* local IP address of interface */
245 };
246 
247 /*
248  * Argument for IP_PORTRANGE:
249  * - which range to search when port is unspecified at bind() or connect()
250  */
251 #define	IP_PORTRANGE_DEFAULT	0	/* default range */
252 #define	IP_PORTRANGE_HIGH	1	/* "high" - request firewall bypass */
253 #define	IP_PORTRANGE_LOW	2	/* "low" - vouchsafe security */
254 
255 /*
256  * Definitions for inet sysctl operations.
257  *
258  * Third level is protocol number.
259  * Fourth level is desired variable within that protocol.
260  */
261 #define	IPPROTO_MAXID	(IPPROTO_IDP + 1)	/* don't list to IPPROTO_MAX */
262 
263 #define	CTL_IPPROTO_NAMES { \
264 	{ "ip", CTLTYPE_NODE }, \
265 	{ "icmp", CTLTYPE_NODE }, \
266 	{ "igmp", CTLTYPE_NODE }, \
267 	{ "ggp", CTLTYPE_NODE }, \
268 	{ 0, 0 }, \
269 	{ 0, 0 }, \
270 	{ "tcp", CTLTYPE_NODE }, \
271 	{ 0, 0 }, \
272 	{ "egp", CTLTYPE_NODE }, \
273 	{ 0, 0 }, \
274 	{ 0, 0 }, \
275 	{ 0, 0 }, \
276 	{ "pup", CTLTYPE_NODE }, \
277 	{ 0, 0 }, \
278 	{ 0, 0 }, \
279 	{ 0, 0 }, \
280 	{ 0, 0 }, \
281 	{ "udp", CTLTYPE_NODE }, \
282 	{ 0, 0 }, \
283 	{ 0, 0 }, \
284 	{ 0, 0 }, \
285 	{ 0, 0 }, \
286 	{ "idp", CTLTYPE_NODE }, \
287 }
288 
289 /*
290  * Names for IP sysctl objects
291  */
292 #define	IPCTL_FORWARDING	1	/* act as router */
293 #define	IPCTL_SENDREDIRECTS	2	/* may send redirects when forwarding */
294 #define	IPCTL_DEFTTL		3	/* default TTL */
295 #ifdef notyet
296 #define	IPCTL_DEFMTU		4	/* default MTU */
297 #endif
298 #define IPCTL_RTEXPIRE		5	/* cloned route expiration time */
299 #define IPCTL_RTMINEXPIRE	6	/* min value for expiration time */
300 #define IPCTL_RTMAXCACHE	7	/* trigger level for dynamic expire */
301 #define	IPCTL_SOURCEROUTE	8	/* may perform source routes */
302 #define	IPCTL_DIRECTEDBROADCAST	9	/* may re-broadcast received packets */
303 #define IPCTL_INTRQMAXLEN	10	/* max length of netisr queue */
304 #define IPCTL_INTRQDROPS	11	/* number of netisr q drops */
305 #define	IPCTL_STATS		12	/* ipstat structure */
306 #define	IPCTL_MAXID		13
307 
308 #define	IPCTL_NAMES { \
309 	{ 0, 0 }, \
310 	{ "forwarding", CTLTYPE_INT }, \
311 	{ "redirect", CTLTYPE_INT }, \
312 	{ "ttl", CTLTYPE_INT }, \
313 	{ "mtu", CTLTYPE_INT }, \
314 	{ "rtexpire", CTLTYPE_INT }, \
315 	{ "rtminexpire", CTLTYPE_INT }, \
316 	{ "rtmaxcache", CTLTYPE_INT }, \
317 	{ "sourceroute", CTLTYPE_INT }, \
318  	{ "directed-broadcast", CTLTYPE_INT }, \
319 	{ "intr-queue-maxlen", CTLTYPE_INT }, \
320 	{ "intr-queue-drops", CTLTYPE_INT }, \
321 	{ "stats", CTLTYPE_STRUCT }, \
322 }
323 
324 
325 #ifdef KERNEL
326 struct ifnet; struct mbuf;	/* forward declarations for Standard C */
327 
328 int	 in_broadcast __P((struct in_addr, struct ifnet *));
329 int	 in_canforward __P((struct in_addr));
330 int	 in_cksum __P((struct mbuf *, int));
331 int	 in_localaddr __P((struct in_addr));
332 char 	*inet_ntoa __P((struct in_addr)); /* in libkern */
333 
334 /* Firewall hooks */
335 struct ip;
336 typedef	int ip_fw_chk_t __P((struct ip**, int, struct ifnet*, int, struct mbuf**));
337 typedef	int ip_fw_ctl_t __P((int, struct mbuf**));
338 extern	ip_fw_chk_t *ip_fw_chk_ptr;
339 extern	ip_fw_ctl_t *ip_fw_ctl_ptr;
340 
341 /* IP NAT hooks */
342 typedef	int ip_nat_t __P((struct ip**, struct mbuf**, struct ifnet*, int));
343 typedef	int ip_nat_ctl_t __P((int, struct mbuf**));
344 extern	ip_nat_t *ip_nat_ptr;
345 extern	ip_nat_ctl_t *ip_nat_ctl_ptr;
346 #define	IP_NAT_IN	0x00000001
347 #define	IP_NAT_OUT	0x00000002
348 
349 #endif /* KERNEL */
350 
351 #endif
352