unpcb.h revision 127976 
1/*
2 * Copyright (c) 1982, 1986, 1989, 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 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	@(#)unpcb.h	8.1 (Berkeley) 6/2/93
30 * $FreeBSD: head/sys/sys/unpcb.h 127976 2004-04-07 04:19:52Z imp $
31 */
32
33#ifndef _SYS_UNPCB_H_
34#define _SYS_UNPCB_H_
35
36#include <sys/queue.h>
37#include <sys/ucred.h>
38
39/*
40 * Protocol control block for an active
41 * instance of a UNIX internal protocol.
42 *
43 * A socket may be associated with a vnode in the
44 * filesystem.  If so, the unp_vnode pointer holds
45 * a reference count to this vnode, which should be irele'd
46 * when the socket goes away.
47 *
48 * A socket may be connected to another socket, in which
49 * case the control block of the socket to which it is connected
50 * is given by unp_conn.
51 *
52 * A socket may be referenced by a number of sockets (e.g. several
53 * sockets may be connected to a datagram socket.)  These sockets
54 * are in a linked list starting with unp_refs, linked through
55 * unp_nextref and null-terminated.  Note that a socket may be referenced
56 * by a number of other sockets and may also reference a socket (not
57 * necessarily one which is referencing it).  This generates
58 * the need for unp_refs and unp_nextref to be separate fields.
59 *
60 * Stream sockets keep copies of receive sockbuf sb_cc and sb_mbcnt
61 * so that changes in the sockbuf may be computed to modify
62 * back pressure on the sender accordingly.
63 */
64typedef	u_quad_t	unp_gen_t;
65LIST_HEAD(unp_head, unpcb);
66
67struct unpcb {
68	LIST_ENTRY(unpcb) unp_link; 	/* glue on list of all PCBs */
69	struct	socket *unp_socket;	/* pointer back to socket */
70	struct	vnode *unp_vnode;	/* if associated with file */
71	ino_t	unp_ino;		/* fake inode number */
72	struct	unpcb *unp_conn;	/* control block of connected socket */
73	struct	unp_head unp_refs;	/* referencing socket linked list */
74	LIST_ENTRY(unpcb) unp_reflink;	/* link in unp_refs list */
75	struct	sockaddr_un *unp_addr;	/* bound address of socket */
76	int	unp_cc;			/* copy of rcv.sb_cc */
77	int	unp_mbcnt;		/* copy of rcv.sb_mbcnt */
78	unp_gen_t unp_gencnt;		/* generation count of this instance */
79	int	unp_flags;		/* flags */
80	struct	xucred unp_peercred;	/* peer credentials, if applicable */
81};
82
83/*
84 * Flags in unp_flags.
85 *
86 * UNP_HAVEPC - indicates that the unp_peercred member is filled in
87 * and is really the credentials of the connected peer.  This is used
88 * to determine whether the contents should be sent to the user or
89 * not.
90 *
91 * UNP_HAVEPCCACHED - indicates that the unp_peercred member is filled
92 * in, but does *not* contain the credentials of the connected peer
93 * (there may not even be a peer).  This is set in unp_listen() when
94 * it fills in unp_peercred for later consumption by unp_connect().
95 */
96#define UNP_HAVEPC			0x001
97#define UNP_HAVEPCCACHED		0x002
98
99#define	sotounpcb(so)	((struct unpcb *)((so)->so_pcb))
100
101/* Hack alert -- this structure depends on <sys/socketvar.h>. */
102#ifdef	_SYS_SOCKETVAR_H_
103struct xunpcb {
104	size_t	xu_len;			/* length of this structure */
105	struct	unpcb *xu_unpp;		/* to help netstat, fstat */
106	struct	unpcb xu_unp;		/* our information */
107	union {
108		struct	sockaddr_un xuu_addr;	/* our bound address */
109		char	xu_dummy1[256];
110	} xu_au;
111#define	xu_addr	xu_au.xuu_addr
112	union {
113		struct	sockaddr_un xuu_caddr; /* their bound address */
114		char	xu_dummy2[256];
115	} xu_cau;
116#define	xu_caddr xu_cau.xuu_caddr
117	struct	xsocket	xu_socket;
118	u_quad_t	xu_alignment_hack;
119};
120
121struct xunpgen {
122	size_t	xug_len;
123	u_int	xug_count;
124	unp_gen_t xug_gen;
125	so_gen_t xug_sogen;
126};
127#endif /* _SYS_SOCKETVAR_H_ */
128
129#endif /* _SYS_UNPCB_H_ */
130