xref: /illumos-gate/usr/src/stand/lib/inet/ipv4_impl.h (revision 7c478bd9)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  *
26  * Internal IPv4 implementation-specific definitions
27  */
28 
29 #ifndef _IPV4_IMPL_H
30 #define	_IPV4_IMPL_H
31 
32 #pragma ident	"%Z%%M%	%I%	%E% SMI"
33 
34 #ifdef	__cplusplus
35 extern "C" {
36 #endif
37 
38 #define	FRAG_MAX	(40)	/* max number of IP fragments per datagram */
39 #define	FRAG_SUCCESS	(0)	/* datagram reassembled ok */
40 #define	FRAG_DUP	(1)	/* duplicate ip fragment */
41 #define	FRAG_NOSLOTS	(2)	/* no more ip fragment slots */
42 #define	FRAG_ATTEMPTS	1	/* Try twice to get all the fragments */
43 
44 /*
45  * IP fragmentation data structure
46  */
47 struct ip_frag {
48 	int16_t		more;	/* Fragment bit (TRUE == MF, FALSE == No more */
49 	int16_t		offset;	/* Offset within the encapsulated datagram */
50 	mblk_t		*mp;	/* Fragment including IP header */
51 	uint16_t	ipid;	/* fragment ident */
52 	int16_t		iplen;	/* IP datagram's length */
53 	int16_t		iphlen;	/* Len of IP header */
54 	uint8_t		ipp;	/* IP protocol */
55 };
56 
57 /*
58  * true offset is in 8 octet units. The high order 3 bits of the IP header
59  * offset field are therefore used for fragmentation flags. Shift these
60  * bits off to produce the true offset. The high order flag bit is unused
61  * (what would be considered the sign bit). Still, we cast the callers
62  * value as an unsigned quantity to ensure it is treated as positive.
63  */
64 #define	IPV4_OFFSET(a)	((uint16_t)(a) << 3)
65 
66 #define	IPV4_VERSION	4
67 #define	IPH_HDR_LENGTH(iph)	(((struct ip *)(iph))->ip_hl << 2)
68 
69 /* ECN code points for IPv4 TOS byte and IPv6 traffic class octet. */
70 #define	IPH_ECN_NECT	0x0	/* Not ECN-Capabable Transport */
71 #define	IPH_ECN_ECT1	0x1	/* ECN-Capable Transport, ECT(1) */
72 #define	IPH_ECN_ECT0	0x2	/* ECN-Capable Transport, ECT(0) */
73 #define	IPH_ECN_CE	0x3	/* ECN-Congestion Experienced (CE) */
74 
75 #define	IPV4_VERSION			4
76 #define	IP_VERSION			IPV4_VERSION
77 #define	IP_SIMPLE_HDR_LENGTH_IN_WORDS	5
78 #define	IP_SIMPLE_HDR_LENGTH		20
79 #define	IP_MAX_HDR_LENGTH		60
80 
81 #define	IP_MIN_MTU			(IP_MAX_HDR_LENGTH + 8)	/* 68 bytes */
82 
83 /*
84  * IP routing table. IP addresses are in network-order.
85  */
86 struct routing {
87 	struct in_addr	dest;
88 	struct in_addr	gateway;
89 	uint8_t		flag;
90 };
91 
92 extern void		ipv4_raw_socket(struct inetboot_socket *, uint8_t);
93 extern void		ipv4_socket_init(struct inetboot_socket *);
94 extern int		ipv4_header_len(struct inetgram *);
95 extern int		ipv4_input(int);
96 extern int		ipv4_output(int, struct inetgram *);
97 extern int		ipv4_tcp_output(int, mblk_t *);
98 extern struct in_addr	*ipv4_get_route(uint8_t, struct in_addr *,
99 			    struct in_addr *);
100 
101 #ifdef	__cplusplus
102 }
103 #endif
104 
105 #endif /* _IPV4_IMPL_H */
106