1 /* $NetBSD: in.h,v 1.77 2006/11/13 05:13:41 dyoung Exp $ */
2
3 /*
4 * Copyright (c) 1982, 1986, 1990, 1993
5 * The Regents of the University of California. All rights reserved.
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 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)in.h 8.3 (Berkeley) 1/3/94
32 */
33
34 /*
35 * Constants and structures defined by the internet system,
36 * Per RFC 790, September 1981, and numerous additions.
37 */
38
39 #ifndef _NETINET_IN_H_
40 #define _NETINET_IN_H_
41
42 #include <machine/int_types.h>
43
44 #ifndef uint8_t
45 typedef __uint8_t uint8_t;
46 #define uint8_t __uint8_t
47 #endif
48
49 #ifndef uint32_t
50 typedef __uint32_t uint32_t;
51 #define uint32_t __uint32_t
52 #endif
53
54 #include <sys/ansi.h>
55
56 #ifndef in_addr_t
57 typedef __in_addr_t in_addr_t;
58 #define in_addr_t __in_addr_t
59 #endif
60
61 #ifndef in_port_t
62 typedef __in_port_t in_port_t;
63 #define in_port_t __in_port_t
64 #endif
65
66 #ifndef sa_family_t
67 typedef __sa_family_t sa_family_t;
68 #define sa_family_t __sa_family_t
69 #endif
70
71 /*
72 * Protocols
73 */
74 #define IPPROTO_IP 0 /* dummy for IP */
75 #define IPPROTO_HOPOPTS 0 /* IP6 hop-by-hop options */
76 #define IPPROTO_ICMP 1 /* control message protocol */
77 #define IPPROTO_IGMP 2 /* group mgmt protocol */
78 #define IPPROTO_GGP 3 /* gateway^2 (deprecated) */
79 #define IPPROTO_IPV4 4 /* IP header */
80 #define IPPROTO_IPIP 4 /* IP inside IP */
81 #define IPPROTO_TCP 6 /* tcp */
82 #define IPPROTO_EGP 8 /* exterior gateway protocol */
83 #define IPPROTO_PUP 12 /* pup */
84 #define IPPROTO_UDP 17 /* user datagram protocol */
85 #define IPPROTO_IDP 22 /* xns idp */
86 #define IPPROTO_TP 29 /* tp-4 w/ class negotiation */
87 #define IPPROTO_IPV6 41 /* IP6 header */
88 #define IPPROTO_ROUTING 43 /* IP6 routing header */
89 #define IPPROTO_FRAGMENT 44 /* IP6 fragmentation header */
90 #define IPPROTO_RSVP 46 /* resource reservation */
91 #define IPPROTO_GRE 47 /* GRE encaps RFC 1701 */
92 #define IPPROTO_ESP 50 /* encap. security payload */
93 #define IPPROTO_AH 51 /* authentication header */
94 #define IPPROTO_MOBILE 55 /* IP Mobility RFC 2004 */
95 #define IPPROTO_IPV6_ICMP 58 /* IPv6 ICMP */
96 #define IPPROTO_ICMPV6 58 /* ICMP6 */
97 #define IPPROTO_NONE 59 /* IP6 no next header */
98 #define IPPROTO_DSTOPTS 60 /* IP6 destination option */
99 #define IPPROTO_EON 80 /* ISO cnlp */
100 #define IPPROTO_ETHERIP 97 /* Ethernet-in-IP */
101 #define IPPROTO_ENCAP 98 /* encapsulation header */
102 #define IPPROTO_PIM 103 /* Protocol indep. multicast */
103 #define IPPROTO_IPCOMP 108 /* IP Payload Comp. Protocol */
104 #define IPPROTO_VRRP 112 /* VRRP RFC 2338 */
105 #define IPPROTO_CARP 112 /* Common Address Resolution Protocol */
106 #define IPPROTO_RAW 255 /* raw IP packet */
107 #define IPPROTO_MAX 256
108
109 /* last return value of *_input(), meaning "all job for this pkt is done". */
110 #define IPPROTO_DONE 257
111
112 /* sysctl placeholder for (FAST_)IPSEC */
113 #define CTL_IPPROTO_IPSEC 258
114
115
116 /*
117 * Local port number conventions:
118 *
119 * Ports < IPPORT_RESERVED are reserved for privileged processes (e.g. root),
120 * unless a kernel is compiled with IPNOPRIVPORTS defined.
121 *
122 * When a user does a bind(2) or connect(2) with a port number of zero,
123 * a non-conflicting local port address is chosen.
124 *
125 * The default range is IPPORT_ANONMIN to IPPORT_ANONMAX, although
126 * that is settable by sysctl(3); net.inet.ip.anonportmin and
127 * net.inet.ip.anonportmax respectively.
128 *
129 * A user may set the IPPROTO_IP option IP_PORTRANGE to change this
130 * default assignment range.
131 *
132 * The value IP_PORTRANGE_DEFAULT causes the default behavior.
133 *
134 * The value IP_PORTRANGE_HIGH is the same as IP_PORTRANGE_DEFAULT,
135 * and exists only for FreeBSD compatibility purposes.
136 *
137 * The value IP_PORTRANGE_LOW changes the range to the "low" are
138 * that is (by convention) restricted to privileged processes.
139 * This convention is based on "vouchsafe" principles only.
140 * It is only secure if you trust the remote host to restrict these ports.
141 * The range is IPPORT_RESERVEDMIN to IPPORT_RESERVEDMAX.
142 */
143
144 #define IPPORT_RESERVED 1024
145 #define IPPORT_ANONMIN 49152
146 #define IPPORT_ANONMAX 65535
147 #define IPPORT_RESERVEDMIN 600
148 #define IPPORT_RESERVEDMAX (IPPORT_RESERVED-1)
149
150 /*
151 * Internet address (a structure for historical reasons)
152 */
153 struct in_addr {
154 in_addr_t s_addr;
155 } __attribute__((__packed__));
156
157 /*
158 * Definitions of bits in internet address integers.
159 * On subnets, the decomposition of addresses to host and net parts
160 * is done according to subnet mask, not the masks here.
161 *
162 * By byte-swapping the constants, we avoid ever having to byte-swap IP
163 * addresses inside the kernel. Unfortunately, user-level programs rely
164 * on these macros not doing byte-swapping.
165 */
166 #ifdef _KERNEL
167 #define __IPADDR(x) ((uint32_t) htonl((uint32_t)(x)))
168 #else
169 #define __IPADDR(x) ((uint32_t)(x))
170 #endif
171
172 #define IN_CLASSA(i) (((uint32_t)(i) & __IPADDR(0x80000000)) == \
173 __IPADDR(0x00000000))
174 #define IN_CLASSA_NET __IPADDR(0xff000000)
175 #define IN_CLASSA_NSHIFT 24
176 #define IN_CLASSA_HOST __IPADDR(0x00ffffff)
177 #define IN_CLASSA_MAX 128
178
179 #define IN_CLASSB(i) (((uint32_t)(i) & __IPADDR(0xc0000000)) == \
180 __IPADDR(0x80000000))
181 #define IN_CLASSB_NET __IPADDR(0xffff0000)
182 #define IN_CLASSB_NSHIFT 16
183 #define IN_CLASSB_HOST __IPADDR(0x0000ffff)
184 #define IN_CLASSB_MAX 65536
185
186 #define IN_CLASSC(i) (((uint32_t)(i) & __IPADDR(0xe0000000)) == \
187 __IPADDR(0xc0000000))
188 #define IN_CLASSC_NET __IPADDR(0xffffff00)
189 #define IN_CLASSC_NSHIFT 8
190 #define IN_CLASSC_HOST __IPADDR(0x000000ff)
191
192 #define IN_CLASSD(i) (((uint32_t)(i) & __IPADDR(0xf0000000)) == \
193 __IPADDR(0xe0000000))
194 /* These ones aren't really net and host fields, but routing needn't know. */
195 #define IN_CLASSD_NET __IPADDR(0xf0000000)
196 #define IN_CLASSD_NSHIFT 28
197 #define IN_CLASSD_HOST __IPADDR(0x0fffffff)
198 #define IN_MULTICAST(i) IN_CLASSD(i)
199
200 #define IN_EXPERIMENTAL(i) (((uint32_t)(i) & __IPADDR(0xf0000000)) == \
201 __IPADDR(0xf0000000))
202 #define IN_BADCLASS(i) (((uint32_t)(i) & __IPADDR(0xf0000000)) == \
203 __IPADDR(0xf0000000))
204
205 #define IN_LINKLOCAL(i) (((uint32_t)(i) & __IPADDR(0xffff0000)) == \
206 __IPADDR(0xa9fe0000))
207
208 #define IN_PRIVATE(i) ((((uint32_t)(i) & __IPADDR(0xff000000)) == \
209 __IPADDR(0x0a000000)) || \
210 (((uint32_t)(i) & __IPADDR(0xfff00000)) == \
211 __IPADDR(0xac100000)) || \
212 (((uint32_t)(i) & __IPADDR(0xffff0000)) == \
213 __IPADDR(0xc0a80000)))
214
215 #define IN_LOCAL_GROUP(i) (((uint32_t)(i) & __IPADDR(0xffffff00)) == \
216 __IPADDR(0xe0000000))
217
218 #define IN_ANY_LOCAL(i) (IN_LINKLOCAL(i) || IN_LOCAL_GROUP(i))
219
220 #define INADDR_ANY __IPADDR(0x00000000)
221 #define INADDR_LOOPBACK __IPADDR(0x7f000001)
222 #define INADDR_BROADCAST __IPADDR(0xffffffff) /* must be masked */
223 #define INADDR_NONE __IPADDR(0xffffffff) /* -1 return */
224
225 #define INADDR_UNSPEC_GROUP __IPADDR(0xe0000000) /* 224.0.0.0 */
226 #define INADDR_ALLHOSTS_GROUP __IPADDR(0xe0000001) /* 224.0.0.1 */
227 #define INADDR_ALLRTRS_GROUP __IPADDR(0xe0000002) /* 224.0.0.2 */
228 #define INADDR_CARP_GROUP __IPADDR(0xe0000012) /* 224.0.0.18 */
229 #define INADDR_MAX_LOCAL_GROUP __IPADDR(0xe00000ff) /* 224.0.0.255 */
230
231 #define IN_LOOPBACKNET 127 /* official! */
232
233 /*
234 * Socket address, internet style.
235 */
236 struct sockaddr_in {
237 uint8_t sin_len;
238 sa_family_t sin_family;
239 in_port_t sin_port;
240 struct in_addr sin_addr;
241 __int8_t sin_zero[8];
242 };
243
244 #define INET_ADDRSTRLEN 16
245
246 /*
247 * Structure used to describe IP options.
248 * Used to store options internally, to pass them to a process,
249 * or to restore options retrieved earlier.
250 * The ip_dst is used for the first-hop gateway when using a source route
251 * (this gets put into the header proper).
252 */
253 struct ip_opts {
254 struct in_addr ip_dst; /* first hop, 0 w/o src rt */
255 #if defined(__cplusplus)
256 __int8_t Ip_opts[40]; /* actually variable in size */
257 #else
258 __int8_t ip_opts[40]; /* actually variable in size */
259 #endif
260 };
261
262 /*
263 * Options for use with [gs]etsockopt at the IP level.
264 * First word of comment is data type; bool is stored in int.
265 */
266 #define IP_OPTIONS 1 /* buf/ip_opts; set/get IP options */
267 #define IP_HDRINCL 2 /* int; header is included with data */
268 #define IP_TOS 3 /* int; IP type of service and preced. */
269 #define IP_TTL 4 /* int; IP time to live */
270 #define IP_RECVOPTS 5 /* bool; receive all IP opts w/dgram */
271 #define IP_RECVRETOPTS 6 /* bool; receive IP opts for response */
272 #define IP_RECVDSTADDR 7 /* bool; receive IP dst addr w/dgram */
273 #define IP_RETOPTS 8 /* ip_opts; set/get IP options */
274 #define IP_MULTICAST_IF 9 /* in_addr; set/get IP multicast i/f */
275 #define IP_MULTICAST_TTL 10 /* u_char; set/get IP multicast ttl */
276 #define IP_MULTICAST_LOOP 11 /* u_char; set/get IP multicast loopback */
277 #define IP_ADD_MEMBERSHIP 12 /* ip_mreq; add an IP group membership */
278 #define IP_DROP_MEMBERSHIP 13 /* ip_mreq; drop an IP group membership */
279 #define IP_PORTRANGE 19 /* int; range to use for ephemeral port */
280 #define IP_RECVIF 20 /* bool; receive reception if w/dgram */
281 #define IP_ERRORMTU 21 /* int; get MTU of last xmit = EMSGSIZE */
282 #if 1 /*IPSEC*/
283 #define IP_IPSEC_POLICY 22 /* struct; get/set security policy */
284 #endif
285
286 /*
287 * Defaults and limits for options
288 */
289 #define IP_DEFAULT_MULTICAST_TTL 1 /* normally limit m'casts to 1 hop */
290 #define IP_DEFAULT_MULTICAST_LOOP 1 /* normally hear sends if a member */
291 #define IP_MAX_MEMBERSHIPS 20 /* per socket; must fit in one mbuf */
292
293 /*
294 * Argument structure for IP_ADD_MEMBERSHIP and IP_DROP_MEMBERSHIP.
295 */
296 struct ip_mreq {
297 struct in_addr imr_multiaddr; /* IP multicast address of group */
298 struct in_addr imr_interface; /* local IP address of interface */
299 };
300
301 /*
302 * Argument for IP_PORTRANGE:
303 * - which range to search when port is unspecified at bind() or connect()
304 */
305 #define IP_PORTRANGE_DEFAULT 0 /* default range */
306 #define IP_PORTRANGE_HIGH 1 /* same as DEFAULT (FreeBSD compat) */
307 #define IP_PORTRANGE_LOW 2 /* use privileged range */
308
309 #if defined(_NETBSD_SOURCE)
310 /*
311 * Definitions for inet sysctl operations.
312 *
313 * Third level is protocol number.
314 * Fourth level is desired variable within that protocol.
315 */
316 #define IPPROTO_MAXID (IPPROTO_AH + 1) /* don't list to IPPROTO_MAX */
317
318 #define CTL_IPPROTO_NAMES { \
319 { "ip", CTLTYPE_NODE }, \
320 { "icmp", CTLTYPE_NODE }, \
321 { "igmp", CTLTYPE_NODE }, \
322 { "ggp", CTLTYPE_NODE }, \
323 { 0, 0 }, \
324 { 0, 0 }, \
325 { "tcp", CTLTYPE_NODE }, \
326 { 0, 0 }, \
327 { "egp", CTLTYPE_NODE }, \
328 { 0, 0 }, \
329 { 0, 0 }, \
330 { 0, 0 }, \
331 { "pup", CTLTYPE_NODE }, \
332 { 0, 0 }, \
333 { 0, 0 }, \
334 { 0, 0 }, \
335 { 0, 0 }, \
336 { "udp", CTLTYPE_NODE }, \
337 { 0, 0 }, \
338 { 0, 0 }, \
339 { 0, 0 }, \
340 { 0, 0 }, \
341 { "idp", CTLTYPE_NODE }, \
342 { 0, 0 }, \
343 { 0, 0 }, \
344 { 0, 0 }, \
345 { 0, 0 }, \
346 { 0, 0 }, \
347 { 0, 0 }, \
348 { 0, 0 }, \
349 { 0, 0 }, \
350 { 0, 0 }, \
351 { 0, 0 }, \
352 { 0, 0 }, \
353 { 0, 0 }, \
354 { 0, 0 }, \
355 { 0, 0 }, \
356 { 0, 0 }, \
357 { 0, 0 }, \
358 { 0, 0 }, \
359 { 0, 0 }, \
360 { 0, 0 }, \
361 { 0, 0 }, \
362 { 0, 0 }, \
363 { 0, 0 }, \
364 { 0, 0 }, \
365 { 0, 0 }, \
366 { 0, 0 }, \
367 { 0, 0 }, \
368 { 0, 0 }, \
369 { 0, 0 }, \
370 { "ipsec", CTLTYPE_NODE }, \
371 { 0, 0 }, \
372 { 0, 0 }, \
373 { 0, 0 }, \
374 { 0, 0 }, \
375 { 0, 0 }, \
376 { 0, 0 }, \
377 { 0, 0 }, \
378 { 0, 0 }, \
379 { 0, 0 }, \
380 { 0, 0 }, \
381 { 0, 0 }, \
382 { 0, 0 }, \
383 { 0, 0 }, \
384 { 0, 0 }, \
385 { 0, 0 }, \
386 { 0, 0 }, \
387 { 0, 0 }, \
388 { 0, 0 }, \
389 { 0, 0 }, \
390 { 0, 0 }, \
391 { 0, 0 }, \
392 { 0, 0 }, \
393 { 0, 0 }, \
394 { 0, 0 }, \
395 { 0, 0 }, \
396 { 0, 0 }, \
397 { 0, 0 }, \
398 { 0, 0 }, \
399 { 0, 0 }, \
400 { 0, 0 }, \
401 { 0, 0 }, \
402 { 0, 0 }, \
403 { 0, 0 }, \
404 { 0, 0 }, \
405 { 0, 0 }, \
406 { 0, 0 }, \
407 { 0, 0 }, \
408 { 0, 0 }, \
409 { 0, 0 }, \
410 { 0, 0 }, \
411 { 0, 0 }, \
412 { 0, 0 }, \
413 { 0, 0 }, \
414 { 0, 0 }, \
415 { 0, 0 }, \
416 { 0, 0 }, \
417 { 0, 0 }, \
418 { 0, 0 }, \
419 { 0, 0 }, \
420 { 0, 0 }, \
421 { 0, 0 }, \
422 { "pim", CTLTYPE_NODE }, \
423 }
424
425 /*
426 * Names for IP sysctl objects
427 */
428 #define IPCTL_FORWARDING 1 /* act as router */
429 #define IPCTL_SENDREDIRECTS 2 /* may send redirects when forwarding */
430 #define IPCTL_DEFTTL 3 /* default TTL */
431 #ifdef notyet
432 #define IPCTL_DEFMTU 4 /* default MTU */
433 #endif
434 #define IPCTL_FORWSRCRT 5 /* forward source-routed packets */
435 #define IPCTL_DIRECTEDBCAST 6 /* default broadcast behavior */
436 #define IPCTL_ALLOWSRCRT 7 /* allow/drop all source-routed pkts */
437 #define IPCTL_SUBNETSARELOCAL 8 /* treat subnets as local addresses */
438 #define IPCTL_MTUDISC 9 /* allow path MTU discovery */
439 #define IPCTL_ANONPORTMIN 10 /* minimum ephemeral port */
440 #define IPCTL_ANONPORTMAX 11 /* maximum ephemeral port */
441 #define IPCTL_MTUDISCTIMEOUT 12 /* allow path MTU discovery */
442 #define IPCTL_MAXFLOWS 13 /* maximum ip flows allowed */
443 #define IPCTL_HOSTZEROBROADCAST 14 /* is host zero a broadcast addr? */
444 #define IPCTL_GIF_TTL 15 /* default TTL for gif encap packet */
445 #define IPCTL_LOWPORTMIN 16 /* minimum reserved port */
446 #define IPCTL_LOWPORTMAX 17 /* maximum reserved port */
447 #define IPCTL_MAXFRAGPACKETS 18 /* max packets reassembly queue */
448 #define IPCTL_GRE_TTL 19 /* default TTL for gre encap packet */
449 #define IPCTL_CHECKINTERFACE 20 /* drop pkts in from 'wrong' iface */
450 #define IPCTL_IFQ 21 /* ipintrq node */
451 #define IPCTL_RANDOMID 22 /* use random IP ids (if configured) */
452 #define IPCTL_LOOPBACKCKSUM 23 /* do IP checksum on loopback */
453 #define IPCTL_STATS 24 /* IP statistics */
454 #define IPCTL_MAXID 25
455
456 #define IPCTL_NAMES { \
457 { 0, 0 }, \
458 { "forwarding", CTLTYPE_INT }, \
459 { "redirect", CTLTYPE_INT }, \
460 { "ttl", CTLTYPE_INT }, \
461 { "mtu", CTLTYPE_INT }, \
462 { "forwsrcrt", CTLTYPE_INT }, \
463 { "directed-broadcast", CTLTYPE_INT }, \
464 { "allowsrcrt", CTLTYPE_INT }, \
465 { "subnetsarelocal", CTLTYPE_INT }, \
466 { "mtudisc", CTLTYPE_INT }, \
467 { "anonportmin", CTLTYPE_INT }, \
468 { "anonportmax", CTLTYPE_INT }, \
469 { "mtudisctimeout", CTLTYPE_INT }, \
470 { "maxflows", CTLTYPE_INT }, \
471 { "hostzerobroadcast", CTLTYPE_INT }, \
472 { "gifttl", CTLTYPE_INT }, \
473 { "lowportmin", CTLTYPE_INT }, \
474 { "lowportmax", CTLTYPE_INT }, \
475 { "maxfragpackets", CTLTYPE_INT }, \
476 { "grettl", CTLTYPE_INT }, \
477 { "checkinterface", CTLTYPE_INT }, \
478 { "ifq", CTLTYPE_NODE }, \
479 { "random_id", CTLTYPE_INT }, \
480 { "do_loopback_cksum", CTLTYPE_INT }, \
481 { "stats", CTLTYPE_STRUCT }, \
482 }
483 #endif /* _NETBSD_SOURCE */
484
485 /* INET6 stuff */
486 #define __KAME_NETINET_IN_H_INCLUDED_
487 #include <netinet6/in6.h>
488 #undef __KAME_NETINET_IN_H_INCLUDED_
489
490 #ifdef _KERNEL
491 /*
492 * in_cksum_phdr:
493 *
494 * Compute significant parts of the IPv4 checksum pseudo-header
495 * for use in a delayed TCP/UDP checksum calculation.
496 *
497 * Args:
498 *
499 * src Source IP address
500 * dst Destination IP address
501 * lenproto htons(proto-hdr-len + proto-number)
502 */
503 static __inline u_int16_t __attribute__((__unused__))
in_cksum_phdr(u_int32_t src,u_int32_t dst,u_int32_t lenproto)504 in_cksum_phdr(u_int32_t src, u_int32_t dst, u_int32_t lenproto)
505 {
506 u_int32_t sum;
507
508 sum = lenproto +
509 (u_int16_t)(src >> 16) +
510 (u_int16_t)(src /*& 0xffff*/) +
511 (u_int16_t)(dst >> 16) +
512 (u_int16_t)(dst /*& 0xffff*/);
513
514 sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/);
515
516 if (sum > 0xffff)
517 sum -= 0xffff;
518
519 return (sum);
520 }
521
522 /*
523 * in_cksum_addword:
524 *
525 * Add the two 16-bit network-order values, carry, and return.
526 */
527 static __inline u_int16_t __attribute__((__unused__))
in_cksum_addword(u_int16_t a,u_int16_t b)528 in_cksum_addword(u_int16_t a, u_int16_t b)
529 {
530 u_int32_t sum = a + b;
531
532 if (sum > 0xffff)
533 sum -= 0xffff;
534
535 return (sum);
536 }
537
538 extern struct in_addr zeroin_addr;
539 extern u_char ip_protox[];
540
541 int in_broadcast(struct in_addr, struct ifnet *);
542 int in_canforward(struct in_addr);
543 int in_cksum(struct mbuf *, int);
544 int in4_cksum(struct mbuf *, u_int8_t, int, int);
545 void in_delayed_cksum(struct mbuf *);
546 int in_localaddr(struct in_addr);
547 void in_socktrim(struct sockaddr_in *);
548
549 #define in_hosteq(s,t) ((s).s_addr == (t).s_addr)
550 #define in_nullhost(x) ((x).s_addr == INADDR_ANY)
551
552 #define satosin(sa) ((struct sockaddr_in *)(sa))
553 #define sintosa(sin) ((struct sockaddr *)(sin))
554 #define ifatoia(ifa) ((struct in_ifaddr *)(ifa))
555 #endif /* _KERNEL */
556
557 #endif /* !_NETINET_IN_H_ */
558