Home | History | Annotate | Line # | Download | only in netinet
in.h revision 1.68
      1 /*	$NetBSD: in.h,v 1.68 2004/09/04 23:30:07 manu 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_ENCAP		98		/* encapsulation header */
    101 #define	IPPROTO_PIM		103		/* Protocol indep. multicast */
    102 #define	IPPROTO_IPCOMP		108		/* IP Payload Comp. Protocol */
    103 #define	IPPROTO_VRRP		112		/* VRRP RFC 2338 */
    104 
    105 #define	IPPROTO_RAW		255		/* raw IP packet */
    106 #define	IPPROTO_MAX		256
    107 
    108 /* last return value of *_input(), meaning "all job for this pkt is done".  */
    109 #define	IPPROTO_DONE		257
    110 
    111 /* sysctl placeholder for (FAST_)IPSEC */
    112 #define CTL_IPPROTO_IPSEC	258
    113 
    114 
    115 /*
    116  * Local port number conventions:
    117  *
    118  * Ports < IPPORT_RESERVED are reserved for privileged processes (e.g. root),
    119  * unless a kernel is compiled with IPNOPRIVPORTS defined.
    120  *
    121  * When a user does a bind(2) or connect(2) with a port number of zero,
    122  * a non-conflicting local port address is chosen.
    123  *
    124  * The default range is IPPORT_ANONMIN to IPPORT_ANONMAX, although
    125  * that is settable by sysctl(3); net.inet.ip.anonportmin and
    126  * net.inet.ip.anonportmax respectively.
    127  *
    128  * A user may set the IPPROTO_IP option IP_PORTRANGE to change this
    129  * default assignment range.
    130  *
    131  * The value IP_PORTRANGE_DEFAULT causes the default behavior.
    132  *
    133  * The value IP_PORTRANGE_HIGH is the same as IP_PORTRANGE_DEFAULT,
    134  * and exists only for FreeBSD compatibility purposes.
    135  *
    136  * The value IP_PORTRANGE_LOW changes the range to the "low" are
    137  * that is (by convention) restricted to privileged processes.
    138  * This convention is based on "vouchsafe" principles only.
    139  * It is only secure if you trust the remote host to restrict these ports.
    140  * The range is IPPORT_RESERVEDMIN to IPPORT_RESERVEDMAX.
    141  */
    142 
    143 #define	IPPORT_RESERVED		1024
    144 #define	IPPORT_ANONMIN		49152
    145 #define	IPPORT_ANONMAX		65535
    146 #define	IPPORT_RESERVEDMIN	600
    147 #define	IPPORT_RESERVEDMAX	(IPPORT_RESERVED-1)
    148 
    149 /*
    150  * Internet address (a structure for historical reasons)
    151  */
    152 struct in_addr {
    153 	in_addr_t s_addr;
    154 } __attribute__((__packed__));
    155 
    156 /*
    157  * Definitions of bits in internet address integers.
    158  * On subnets, the decomposition of addresses to host and net parts
    159  * is done according to subnet mask, not the masks here.
    160  *
    161  * By byte-swapping the constants, we avoid ever having to byte-swap IP
    162  * addresses inside the kernel.  Unfortunately, user-level programs rely
    163  * on these macros not doing byte-swapping.
    164  */
    165 #ifdef _KERNEL
    166 #define	__IPADDR(x)	((uint32_t) htonl((uint32_t)(x)))
    167 #else
    168 #define	__IPADDR(x)	((uint32_t)(x))
    169 #endif
    170 
    171 #define	IN_CLASSA(i)		(((uint32_t)(i) & __IPADDR(0x80000000)) == \
    172 				 __IPADDR(0x00000000))
    173 #define	IN_CLASSA_NET		__IPADDR(0xff000000)
    174 #define	IN_CLASSA_NSHIFT	24
    175 #define	IN_CLASSA_HOST		__IPADDR(0x00ffffff)
    176 #define	IN_CLASSA_MAX		128
    177 
    178 #define	IN_CLASSB(i)		(((uint32_t)(i) & __IPADDR(0xc0000000)) == \
    179 				 __IPADDR(0x80000000))
    180 #define	IN_CLASSB_NET		__IPADDR(0xffff0000)
    181 #define	IN_CLASSB_NSHIFT	16
    182 #define	IN_CLASSB_HOST		__IPADDR(0x0000ffff)
    183 #define	IN_CLASSB_MAX		65536
    184 
    185 #define	IN_CLASSC(i)		(((uint32_t)(i) & __IPADDR(0xe0000000)) == \
    186 				 __IPADDR(0xc0000000))
    187 #define	IN_CLASSC_NET		__IPADDR(0xffffff00)
    188 #define	IN_CLASSC_NSHIFT	8
    189 #define	IN_CLASSC_HOST		__IPADDR(0x000000ff)
    190 
    191 #define	IN_CLASSD(i)		(((uint32_t)(i) & __IPADDR(0xf0000000)) == \
    192 				 __IPADDR(0xe0000000))
    193 /* These ones aren't really net and host fields, but routing needn't know. */
    194 #define	IN_CLASSD_NET		__IPADDR(0xf0000000)
    195 #define	IN_CLASSD_NSHIFT	28
    196 #define	IN_CLASSD_HOST		__IPADDR(0x0fffffff)
    197 #define	IN_MULTICAST(i)		IN_CLASSD(i)
    198 
    199 #define	IN_EXPERIMENTAL(i)	(((uint32_t)(i) & __IPADDR(0xf0000000)) == \
    200 				 __IPADDR(0xf0000000))
    201 #define	IN_BADCLASS(i)		(((uint32_t)(i) & __IPADDR(0xf0000000)) == \
    202 				 __IPADDR(0xf0000000))
    203 
    204 #define	IN_LOCAL_GROUP(i)	(((uint32_t)(i) & __IPADDR(0xffffff00)) == \
    205 				 __IPADDR(0xe0000000))
    206 
    207 #define	INADDR_ANY		__IPADDR(0x00000000)
    208 #define	INADDR_LOOPBACK		__IPADDR(0x7f000001)
    209 #define	INADDR_BROADCAST	__IPADDR(0xffffffff)	/* must be masked */
    210 #ifndef _KERNEL
    211 #define	INADDR_NONE		__IPADDR(0xffffffff)	/* -1 return */
    212 #endif
    213 
    214 #define	INADDR_UNSPEC_GROUP	__IPADDR(0xe0000000)	/* 224.0.0.0 */
    215 #define	INADDR_ALLHOSTS_GROUP	__IPADDR(0xe0000001)	/* 224.0.0.1 */
    216 #define	INADDR_ALLRTRS_GROUP	__IPADDR(0xe0000002)	/* 224.0.0.2 */
    217 #define	INADDR_MAX_LOCAL_GROUP	__IPADDR(0xe00000ff)	/* 224.0.0.255 */
    218 
    219 #define	IN_LOOPBACKNET		127			/* official! */
    220 
    221 /*
    222  * Socket address, internet style.
    223  */
    224 struct sockaddr_in {
    225 	uint8_t		sin_len;
    226 	sa_family_t	sin_family;
    227 	in_port_t	sin_port;
    228 	struct in_addr	sin_addr;
    229 	__int8_t	sin_zero[8];
    230 };
    231 
    232 #define	INET_ADDRSTRLEN                 16
    233 
    234 /*
    235  * Structure used to describe IP options.
    236  * Used to store options internally, to pass them to a process,
    237  * or to restore options retrieved earlier.
    238  * The ip_dst is used for the first-hop gateway when using a source route
    239  * (this gets put into the header proper).
    240  */
    241 struct ip_opts {
    242 	struct in_addr	ip_dst;		/* first hop, 0 w/o src rt */
    243 #if defined(__cplusplus)
    244 	__int8_t	Ip_opts[40];	/* actually variable in size */
    245 #else
    246 	__int8_t	ip_opts[40];	/* actually variable in size */
    247 #endif
    248 };
    249 
    250 /*
    251  * Options for use with [gs]etsockopt at the IP level.
    252  * First word of comment is data type; bool is stored in int.
    253  */
    254 #define	IP_OPTIONS		1    /* buf/ip_opts; set/get IP options */
    255 #define	IP_HDRINCL		2    /* int; header is included with data */
    256 #define	IP_TOS			3    /* int; IP type of service and preced. */
    257 #define	IP_TTL			4    /* int; IP time to live */
    258 #define	IP_RECVOPTS		5    /* bool; receive all IP opts w/dgram */
    259 #define	IP_RECVRETOPTS		6    /* bool; receive IP opts for response */
    260 #define	IP_RECVDSTADDR		7    /* bool; receive IP dst addr w/dgram */
    261 #define	IP_RETOPTS		8    /* ip_opts; set/get IP options */
    262 #define	IP_MULTICAST_IF		9    /* in_addr; set/get IP multicast i/f  */
    263 #define	IP_MULTICAST_TTL	10   /* u_char; set/get IP multicast ttl */
    264 #define	IP_MULTICAST_LOOP	11   /* u_char; set/get IP multicast loopback */
    265 #define	IP_ADD_MEMBERSHIP	12   /* ip_mreq; add an IP group membership */
    266 #define	IP_DROP_MEMBERSHIP	13   /* ip_mreq; drop an IP group membership */
    267 #define	IP_PORTRANGE		19   /* int; range to use for ephemeral port */
    268 #define	IP_RECVIF		20   /* bool; receive reception if w/dgram */
    269 #define	IP_ERRORMTU		21   /* int; get MTU of last xmit = EMSGSIZE */
    270 #if 1 /*IPSEC*/
    271 #define	IP_IPSEC_POLICY		22 /* struct; get/set security policy */
    272 #endif
    273 
    274 /*
    275  * Defaults and limits for options
    276  */
    277 #define	IP_DEFAULT_MULTICAST_TTL  1	/* normally limit m'casts to 1 hop  */
    278 #define	IP_DEFAULT_MULTICAST_LOOP 1	/* normally hear sends if a member  */
    279 #define	IP_MAX_MEMBERSHIPS	20	/* per socket; must fit in one mbuf */
    280 
    281 /*
    282  * Argument structure for IP_ADD_MEMBERSHIP and IP_DROP_MEMBERSHIP.
    283  */
    284 struct ip_mreq {
    285 	struct	in_addr imr_multiaddr;	/* IP multicast address of group */
    286 	struct	in_addr imr_interface;	/* local IP address of interface */
    287 };
    288 
    289 /*
    290  * Argument for IP_PORTRANGE:
    291  * - which range to search when port is unspecified at bind() or connect()
    292  */
    293 #define	IP_PORTRANGE_DEFAULT	0	/* default range */
    294 #define	IP_PORTRANGE_HIGH	1	/* same as DEFAULT (FreeBSD compat) */
    295 #define	IP_PORTRANGE_LOW	2	/* use privileged range */
    296 
    297 #if defined(_NETBSD_SOURCE)
    298 /*
    299  * Definitions for inet sysctl operations.
    300  *
    301  * Third level is protocol number.
    302  * Fourth level is desired variable within that protocol.
    303  */
    304 #define	IPPROTO_MAXID	(IPPROTO_AH + 1)	/* don't list to IPPROTO_MAX */
    305 
    306 #define	CTL_IPPROTO_NAMES { \
    307 	{ "ip", CTLTYPE_NODE }, \
    308 	{ "icmp", CTLTYPE_NODE }, \
    309 	{ "igmp", CTLTYPE_NODE }, \
    310 	{ "ggp", CTLTYPE_NODE }, \
    311 	{ 0, 0 }, \
    312 	{ 0, 0 }, \
    313 	{ "tcp", CTLTYPE_NODE }, \
    314 	{ 0, 0 }, \
    315 	{ "egp", CTLTYPE_NODE }, \
    316 	{ 0, 0 }, \
    317 	{ 0, 0 }, \
    318 	{ 0, 0 }, \
    319 	{ "pup", CTLTYPE_NODE }, \
    320 	{ 0, 0 }, \
    321 	{ 0, 0 }, \
    322 	{ 0, 0 }, \
    323 	{ 0, 0 }, \
    324 	{ "udp", CTLTYPE_NODE }, \
    325 	{ 0, 0 }, \
    326 	{ 0, 0 }, \
    327 	{ 0, 0 }, \
    328 	{ 0, 0 }, \
    329 	{ "idp", CTLTYPE_NODE }, \
    330 	{ 0, 0 }, \
    331 	{ 0, 0 }, \
    332 	{ 0, 0 }, \
    333 	{ 0, 0 }, \
    334 	{ 0, 0 }, \
    335 	{ 0, 0 }, \
    336 	{ 0, 0 }, \
    337 	{ 0, 0 }, \
    338 	{ 0, 0 }, \
    339 	{ 0, 0 }, \
    340 	{ 0, 0 }, \
    341 	{ 0, 0 }, \
    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 	{ "ipsec", CTLTYPE_NODE }, \
    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 	{ 0, 0 }, \
    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 	{ "pim", CTLTYPE_NODE }, \
    411 }
    412 
    413 /*
    414  * Names for IP sysctl objects
    415  */
    416 #define	IPCTL_FORWARDING	1	/* act as router */
    417 #define	IPCTL_SENDREDIRECTS	2	/* may send redirects when forwarding */
    418 #define	IPCTL_DEFTTL		3	/* default TTL */
    419 #ifdef notyet
    420 #define	IPCTL_DEFMTU		4	/* default MTU */
    421 #endif
    422 #define	IPCTL_FORWSRCRT		5	/* forward source-routed packets */
    423 #define	IPCTL_DIRECTEDBCAST	6	/* default broadcast behavior */
    424 #define	IPCTL_ALLOWSRCRT	7	/* allow/drop all source-routed pkts */
    425 #define	IPCTL_SUBNETSARELOCAL	8	/* treat subnets as local addresses */
    426 #define	IPCTL_MTUDISC		9	/* allow path MTU discovery */
    427 #define	IPCTL_ANONPORTMIN      10	/* minimum ephemeral port */
    428 #define	IPCTL_ANONPORTMAX      11	/* maximum ephemeral port */
    429 #define	IPCTL_MTUDISCTIMEOUT   12	/* allow path MTU discovery */
    430 #define	IPCTL_MAXFLOWS         13	/* maximum ip flows allowed */
    431 #define	IPCTL_HOSTZEROBROADCAST 14	/* is host zero a broadcast addr? */
    432 #define	IPCTL_GIF_TTL 	       15	/* default TTL for gif encap packet */
    433 #define	IPCTL_LOWPORTMIN       16	/* minimum reserved port */
    434 #define	IPCTL_LOWPORTMAX       17	/* maximum reserved port */
    435 #define	IPCTL_MAXFRAGPACKETS   18	/* max packets reassembly queue */
    436 #define	IPCTL_GRE_TTL          19	/* default TTL for gre encap packet */
    437 #define	IPCTL_CHECKINTERFACE   20	/* drop pkts in from 'wrong' iface */
    438 #define	IPCTL_IFQ	       21	/* ipintrq node */
    439 #define	IPCTL_RANDOMID	       22	/* use random IP ids (if configured) */
    440 #define	IPCTL_MAXID	       23
    441 
    442 #define	IPCTL_NAMES { \
    443 	{ 0, 0 }, \
    444 	{ "forwarding", CTLTYPE_INT }, \
    445 	{ "redirect", CTLTYPE_INT }, \
    446 	{ "ttl", CTLTYPE_INT }, \
    447 	{ "mtu", CTLTYPE_INT }, \
    448 	{ "forwsrcrt", CTLTYPE_INT }, \
    449 	{ "directed-broadcast", CTLTYPE_INT }, \
    450 	{ "allowsrcrt", CTLTYPE_INT }, \
    451 	{ "subnetsarelocal", CTLTYPE_INT }, \
    452 	{ "mtudisc", CTLTYPE_INT }, \
    453 	{ "anonportmin", CTLTYPE_INT }, \
    454 	{ "anonportmax", CTLTYPE_INT }, \
    455 	{ "mtudisctimeout", CTLTYPE_INT }, \
    456 	{ "maxflows", CTLTYPE_INT }, \
    457 	{ "hostzerobroadcast", CTLTYPE_INT }, \
    458 	{ "gifttl", CTLTYPE_INT }, \
    459 	{ "lowportmin", CTLTYPE_INT }, \
    460 	{ "lowportmax", CTLTYPE_INT }, \
    461 	{ "maxfragpackets", CTLTYPE_INT }, \
    462 	{ "grettl", CTLTYPE_INT }, \
    463 	{ "checkinterface", CTLTYPE_INT }, \
    464 	{ "ifq", CTLTYPE_NODE }, \
    465 	{ "random_id", CTLTYPE_INT }, \
    466 }
    467 #endif /* _NETBSD_SOURCE */
    468 
    469 /* INET6 stuff */
    470 #define	__KAME_NETINET_IN_H_INCLUDED_
    471 #include <netinet6/in6.h>
    472 #undef __KAME_NETINET_IN_H_INCLUDED_
    473 
    474 #ifdef _KERNEL
    475 /*
    476  * in_cksum_phdr:
    477  *
    478  *	Compute significant parts of the IPv4 checksum pseudo-header
    479  *	for use in a delayed TCP/UDP checksum calculation.
    480  *
    481  *	Args:
    482  *
    483  *		src		Source IP address
    484  *		dst		Destination IP address
    485  *		lenproto	htons(proto-hdr-len + proto-number)
    486  */
    487 static __inline u_int16_t __attribute__((__unused__))
    488 in_cksum_phdr(u_int32_t src, u_int32_t dst, u_int32_t lenproto)
    489 {
    490 	u_int32_t sum;
    491 
    492 	sum = lenproto +
    493 	      (u_int16_t)(src >> 16) +
    494 	      (u_int16_t)(src /*& 0xffff*/) +
    495 	      (u_int16_t)(dst >> 16) +
    496 	      (u_int16_t)(dst /*& 0xffff*/);
    497 
    498 	sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/);
    499 
    500 	if (sum > 0xffff)
    501 		sum -= 0xffff;
    502 
    503 	return (sum);
    504 }
    505 
    506 /*
    507  * in_cksum_addword:
    508  *
    509  *	Add the two 16-bit network-order values, carry, and return.
    510  */
    511 static __inline u_int16_t __attribute__((__unused__))
    512 in_cksum_addword(u_int16_t a, u_int16_t b)
    513 {
    514 	u_int32_t sum = a + b;
    515 
    516 	if (sum > 0xffff)
    517 		sum -= 0xffff;
    518 
    519 	return (sum);
    520 }
    521 
    522 extern	struct in_addr zeroin_addr;
    523 extern	u_char	ip_protox[];
    524 
    525 int	in_broadcast(struct in_addr, struct ifnet *);
    526 int	in_canforward(struct in_addr);
    527 int	in_cksum(struct mbuf *, int);
    528 int	in4_cksum(struct mbuf *, u_int8_t, int, int);
    529 void	in_delayed_cksum(struct mbuf *);
    530 int	in_localaddr(struct in_addr);
    531 void	in_socktrim(struct sockaddr_in *);
    532 
    533 #define	in_hosteq(s,t)	((s).s_addr == (t).s_addr)
    534 #define	in_nullhost(x)	((x).s_addr == INADDR_ANY)
    535 
    536 #define	satosin(sa)	((struct sockaddr_in *)(sa))
    537 #define	sintosa(sin)	((struct sockaddr *)(sin))
    538 #define	ifatoia(ifa)	((struct in_ifaddr *)(ifa))
    539 #endif /* _KERNEL */
    540 
    541 #endif /* !_NETINET_IN_H_ */
    542