1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1989, 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 * @(#)unpcb.h 8.1 (Berkeley) 6/2/93 32 * $FreeBSD$ 33 */ 34 35 #ifndef _SYS_UNPCB_H_ 36 #define _SYS_UNPCB_H_ 37 38 typedef uint64_t unp_gen_t; 39 40 #if defined(_KERNEL) || defined(_WANT_UNPCB) 41 #include <sys/queue.h> 42 #include <sys/ucred.h> 43 44 /* 45 * Protocol control block for an active 46 * instance of a UNIX internal protocol. 47 * 48 * A socket may be associated with a vnode in the 49 * filesystem. If so, the unp_vnode pointer holds 50 * a reference count to this vnode, which should be irele'd 51 * when the socket goes away. 52 * 53 * A socket may be connected to another socket, in which 54 * case the control block of the socket to which it is connected 55 * is given by unp_conn. 56 * 57 * A socket may be referenced by a number of sockets (e.g. several 58 * sockets may be connected to a datagram socket.) These sockets 59 * are in a linked list starting with unp_refs, linked through 60 * unp_nextref and null-terminated. Note that a socket may be referenced 61 * by a number of other sockets and may also reference a socket (not 62 * necessarily one which is referencing it). This generates 63 * the need for unp_refs and unp_nextref to be separate fields. 64 * 65 * Stream sockets keep copies of receive sockbuf sb_cc and sb_mbcnt 66 * so that changes in the sockbuf may be computed to modify 67 * back pressure on the sender accordingly. 68 */ 69 LIST_HEAD(unp_head, unpcb); 70 71 struct unpcb { 72 /* Cache line 1 */ 73 struct mtx unp_mtx; /* mutex */ 74 struct unpcb *unp_conn; /* control block of connected socket */ 75 volatile u_int unp_refcount; 76 short unp_flags; /* flags */ 77 short unp_gcflag; /* Garbage collector flags. */ 78 struct sockaddr_un *unp_addr; /* bound address of socket */ 79 struct socket *unp_socket; /* pointer back to socket */ 80 /* Cache line 2 */ 81 struct vnode *unp_vnode; /* if associated with file */ 82 struct xucred unp_peercred; /* peer credentials, if applicable */ 83 LIST_ENTRY(unpcb) unp_reflink; /* link in unp_refs list */ 84 LIST_ENTRY(unpcb) unp_link; /* glue on list of all PCBs */ 85 struct unp_head unp_refs; /* referencing socket linked list */ 86 unp_gen_t unp_gencnt; /* generation count of this instance */ 87 struct file *unp_file; /* back-pointer to file for gc. */ 88 u_int unp_msgcount; /* references from message queue */ 89 ino_t unp_ino; /* fake inode number */ 90 } __aligned(CACHE_LINE_SIZE); 91 92 /* 93 * Flags in unp_flags. 94 * 95 * UNP_HAVEPC - indicates that the unp_peercred member is filled in 96 * and is really the credentials of the connected peer. This is used 97 * to determine whether the contents should be sent to the user or 98 * not. 99 */ 100 #define UNP_HAVEPC 0x001 101 #define UNP_WANTCRED 0x004 /* credentials wanted */ 102 #define UNP_CONNWAIT 0x008 /* connect blocks until accepted */ 103 104 /* 105 * These flags are used to handle non-atomicity in connect() and bind() 106 * operations on a socket: in particular, to avoid races between multiple 107 * threads or processes operating simultaneously on the same socket. 108 */ 109 #define UNP_CONNECTING 0x010 /* Currently connecting. */ 110 #define UNP_BINDING 0x020 /* Currently binding. */ 111 #define UNP_NASCENT 0x040 /* Newborn child socket. */ 112 113 /* 114 * Flags in unp_gcflag. 115 */ 116 #define UNPGC_REF 0x1 /* unpcb has external ref. */ 117 #define UNPGC_DEAD 0x2 /* unpcb might be dead. */ 118 #define UNPGC_SCANNED 0x4 /* Has been scanned. */ 119 #define UNPGC_IGNORE_RIGHTS 0x8 /* Attached rights are freed */ 120 121 #define sotounpcb(so) ((struct unpcb *)((so)->so_pcb)) 122 123 #endif /* _KERNEL || _WANT_UNPCB */ 124 125 /* 126 * UNPCB structure exported to user-land via sysctl(3). 127 * 128 * Fields prefixed with "xu_" are unique to the export structure, and fields 129 * with "unp_" or other prefixes match corresponding fields of 'struct unpcb'. 130 * 131 * Legend: 132 * (s) - used by userland utilities in src 133 * (p) - used by utilities in ports 134 * (3) - is known to be used by third party software not in ports 135 * (n) - no known usage 136 * 137 * Evil hack: declare only if sys/socketvar.h have been included. 138 */ 139 #ifdef _SYS_SOCKETVAR_H_ 140 struct xunpcb { 141 ksize_t xu_len; /* length of this structure */ 142 kvaddr_t xu_unpp; /* to help netstat, fstat */ 143 kvaddr_t unp_vnode; /* (s) */ 144 kvaddr_t unp_conn; /* (s) */ 145 kvaddr_t xu_firstref; /* (s) */ 146 kvaddr_t xu_nextref; /* (s) */ 147 unp_gen_t unp_gencnt; /* (s) */ 148 int64_t xu_spare64[8]; 149 int32_t xu_spare32[8]; 150 union { 151 struct sockaddr_un xu_addr; /* our bound address */ 152 char xu_dummy1[256]; 153 }; 154 union { 155 struct sockaddr_un xu_caddr; /* their bound address */ 156 char xu_dummy2[256]; 157 }; 158 struct xsocket xu_socket; 159 } __aligned(8); 160 161 struct xunpgen { 162 ksize_t xug_len; 163 u_int xug_count; 164 unp_gen_t xug_gen; 165 so_gen_t xug_sogen; 166 } __aligned(8);; 167 #endif /* _SYS_SOCKETVAR_H_ */ 168 169 #if defined(_KERNEL) 170 struct thread; 171 172 /* In uipc_userreq.c */ 173 void 174 unp_copy_peercred(struct thread *td, struct unpcb *client_unp, 175 struct unpcb *server_unp, struct unpcb *listen_unp); 176 #endif 177 178 #endif /* _SYS_UNPCB_H_ */ 179