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 * $FreeBSD$ 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 */ 64 typedef u_quad_t unp_gen_t; 65 LIST_HEAD(unp_head, unpcb); 66 67 struct unpcb { 68 LIST_ENTRY(unpcb) unp_link; /* glue on list of all PCBs */ 69 struct socket *unp_socket; /* pointer back to socket */ 70 struct file *unp_file; /* back-pointer to file for gc. */ 71 struct vnode *unp_vnode; /* if associated with file */ 72 ino_t unp_ino; /* fake inode number */ 73 struct unpcb *unp_conn; /* control block of connected socket */ 74 struct unp_head unp_refs; /* referencing socket linked list */ 75 LIST_ENTRY(unpcb) unp_reflink; /* link in unp_refs list */ 76 struct sockaddr_un *unp_addr; /* bound address of socket */ 77 int reserved1; 78 int reserved2; 79 unp_gen_t unp_gencnt; /* generation count of this instance */ 80 short unp_flags; /* flags */ 81 short unp_gcflag; /* Garbage collector flags. */ 82 struct xucred unp_peercred; /* peer credentials, if applicable */ 83 u_int unp_refcount; 84 u_int unp_msgcount; /* references from message queue */ 85 struct mtx unp_mtx; /* mutex */ 86 }; 87 88 /* 89 * Flags in unp_flags. 90 * 91 * UNP_HAVEPC - indicates that the unp_peercred member is filled in 92 * and is really the credentials of the connected peer. This is used 93 * to determine whether the contents should be sent to the user or 94 * not. 95 * 96 * UNP_HAVEPCCACHED - indicates that the unp_peercred member is filled 97 * in, but does *not* contain the credentials of the connected peer 98 * (there may not even be a peer). This is set in unp_listen() when 99 * it fills in unp_peercred for later consumption by unp_connect(). 100 */ 101 #define UNP_HAVEPC 0x001 102 #define UNP_HAVEPCCACHED 0x002 103 #define UNP_WANTCRED 0x004 /* credentials wanted */ 104 #define UNP_CONNWAIT 0x008 /* connect blocks until accepted */ 105 106 #define UNPGC_REF 0x1 /* unpcb has external ref. */ 107 #define UNPGC_DEAD 0x2 /* unpcb might be dead. */ 108 #define UNPGC_SCANNED 0x4 /* Has been scanned. */ 109 110 /* 111 * These flags are used to handle non-atomicity in connect() and bind() 112 * operations on a socket: in particular, to avoid races between multiple 113 * threads or processes operating simultaneously on the same socket. 114 */ 115 #define UNP_CONNECTING 0x010 /* Currently connecting. */ 116 #define UNP_BINDING 0x020 /* Currently binding. */ 117 118 #define sotounpcb(so) ((struct unpcb *)((so)->so_pcb)) 119 120 /* Hack alert -- this structure depends on <sys/socketvar.h>. */ 121 #ifdef _SYS_SOCKETVAR_H_ 122 struct xunpcb { 123 size_t xu_len; /* length of this structure */ 124 struct unpcb *xu_unpp; /* to help netstat, fstat */ 125 struct unpcb xu_unp; /* our information */ 126 union { 127 struct sockaddr_un xuu_addr; /* our bound address */ 128 char xu_dummy1[256]; 129 } xu_au; 130 #define xu_addr xu_au.xuu_addr 131 union { 132 struct sockaddr_un xuu_caddr; /* their bound address */ 133 char xu_dummy2[256]; 134 } xu_cau; 135 #define xu_caddr xu_cau.xuu_caddr 136 struct xsocket xu_socket; 137 u_quad_t xu_alignment_hack; 138 }; 139 140 struct xunpgen { 141 size_t xug_len; 142 u_int xug_count; 143 unp_gen_t xug_gen; 144 so_gen_t xug_sogen; 145 }; 146 #endif /* _SYS_SOCKETVAR_H_ */ 147 148 #endif /* _SYS_UNPCB_H_ */ 149