LCOM1920-T02G10

/*        $NetBSD: unpcb.h,v 1.17 2008/04/24 11:38:39 ad Exp $        */

/*

 * Copyright (c) 1982, 1986, 1989, 1993

 *        The Regents of the University of California.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the University nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 *        @(#)unpcb.h        8.1 (Berkeley) 6/2/93

 */

#ifndef _SYS_UNPCB_H_

#define _SYS_UNPCB_H_

#include <sys/un.h>

#include <sys/mutex.h>

/*

 * Protocol control block for an active

 * instance of a UNIX internal protocol.

 *

 * A socket may be associated with an vnode in the

 * file system.  If so, the unp_vnode pointer holds

 * a reference count to this vnode, which should be irele'd

 * when the socket goes away.

 *

 * A socket may be connected to another socket, in which

 * case the control block of the socket to which it is connected

 * is given by unp_conn.

 *

 * A socket may be referenced by a number of sockets (e.g. several

 * sockets may be connected to a datagram socket.)  These sockets

 * are in a linked list starting with unp_refs, linked through

 * unp_nextref and null-terminated.  Note that a socket may be referenced

 * by a number of other sockets and may also reference a socket (not

 * necessarily one which is referencing it).  This generates

 * the need for unp_refs and unp_nextref to be separate fields.

 *

 * Stream sockets keep copies of receive sockbuf sb_cc and sb_mbcnt

 * so that changes in the sockbuf may be computed to modify

 * back pressure on the sender accordingly.

 *

 * The unp_ctime holds the creation time of the socket: it might be part of

 * a socketpair created by pipe(2), and POSIX requires pipe(2) to initialize

 * a stat structure's st_[acm]time members with the pipe's creation time.

 * N.B.: updating st_[am]time when reading/writing the pipe is not required,

 *       so we just use a single timespec and do not implement that.

 */

struct        unpcb {

        struct        socket *unp_socket;        /* pointer back to socket */

        struct        vnode *unp_vnode;        /* if associated with file */

        ino_t        unp_ino;                /* fake inode number */

        struct        unpcb *unp_conn;        /* control block of connected socket */

        struct        unpcb *unp_refs;        /* referencing socket linked list */

        struct         unpcb *unp_nextref;        /* link in unp_refs list */

        struct        sockaddr_un *unp_addr;        /* bound address of socket */

        kmutex_t *unp_streamlock;        /* lock for est. stream connections */

        size_t        unp_addrlen;                /* size of socket address */

        int        unp_cc;                        /* copy of rcv.sb_cc */

        int        unp_mbcnt;                /* copy of rcv.sb_mbcnt */

        struct        timespec unp_ctime;        /* holds creation time */

        int        unp_flags;                /* misc flags; see below*/

        struct        unpcbid unp_connid;         /* pid and eids of peer */

};

/*

 * Flags in unp_flags.

 *

 * UNP_EIDSVALID - indicates that the unp_connid member is filled in

 * and is really the effective ids of the connected peer.  This is used

 * to determine whether the contents should be sent to the user or

 * not.

 *

 * UNP_EIDSBIND - indicates that the unp_connid member is filled

 * in with data for the listening process.  This is set up in unp_bind() when

 * it fills in unp_connid for later consumption by unp_connect().

 */

#define        UNP_WANTCRED        0x0001                /* credentials wanted */

#define        UNP_CONNWAIT        0x0002                /* connect blocks until accepted */

#define        UNP_EIDSVALID        0x0004                /* unp_connid contains valid data */

#define        UNP_EIDSBIND        0x0008                /* unp_connid was set by bind() */

#define        UNP_BUSY        0x0010                /* busy connecting or binding */

#define        sotounpcb(so)        ((struct unpcb *)((so)->so_pcb))

#endif /* !_SYS_UNPCB_H_ */