/*- * SPDX-License-Identifier: BSD-3-Clause * * 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. */ #ifndef _SYS_UNPCB_H_ #define _SYS_UNPCB_H_ typedef uint64_t unp_gen_t; #if defined(_KERNEL) || defined(_WANT_UNPCB) #include <sys/queue.h> #include <sys/ucred.h> /* * Protocol control block for an active * instance of a UNIX internal protocol. * * A socket may be associated with a vnode in the * filesystem. 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. * * Locking key: * (a) Atomic * (c) Constant * (g) Locked using linkage lock * (l) Locked using list lock * (p) Locked using pcb lock */ LIST_HEAD(unp_head, unpcb); struct unpcb { /* Cache line 1 */ struct mtx unp_mtx; /* PCB mutex */ struct unpcb *unp_conn; /* (p) connected socket */ volatile u_int unp_refcount; /* (a, p) atomic refcount */ short unp_flags; /* (p) PCB flags */ short unp_gcflag; /* (g) Garbage collector flags */ struct sockaddr_un *unp_addr; /* (p) bound address of socket */ struct socket *unp_socket; /* (c) pointer back to socket */ /* Cache line 2 */ u_int unp_pairbusy; /* (p) threads acquiring peer locks */ struct vnode *unp_vnode; /* (p) associated file if applicable */ struct xucred unp_peercred; /* (p) peer credentials if applicable */ LIST_ENTRY(unpcb) unp_reflink; /* (l) link in unp_refs list */ LIST_ENTRY(unpcb) unp_link; /* (g) glue on list of all PCBs */ struct unp_head unp_refs; /* (l) referencing socket linked list */ unp_gen_t unp_gencnt; /* (g) generation count of this item */ struct file *unp_file; /* (g) back-pointer to file for gc */ u_int unp_msgcount; /* (g) references from message queue */ u_int unp_gcrefs; /* (g) garbage collector refcount */ ino_t unp_ino; /* (g) fake inode number */ mode_t unp_mode; /* (g) initial pre-bind() mode */ LIST_ENTRY(unpcb) unp_dead; /* (g) link in dead list */ } __aligned(CACHE_LINE_SIZE); /* * Flags in unp_flags. * * UNP_HAVEPC - indicates that the unp_peercred member is filled in * and is really the credentials of the connected peer. This is used * to determine whether the contents should be sent to the user or * not. */ #define UNP_HAVEPC 0x001 #define UNP_WANTCRED_ALWAYS 0x002 /* credentials wanted always */ #define UNP_WANTCRED_ONESHOT 0x004 /* credentials wanted once */ #define UNP_WANTCRED_MASK (UNP_WANTCRED_ONESHOT | UNP_WANTCRED_ALWAYS) /* * These flags are used to handle non-atomicity in connect() and bind() * operations on a socket: in particular, to avoid races between multiple * threads or processes operating simultaneously on the same socket. */ #define UNP_CONNECTING 0x010 /* Currently connecting. */ #define UNP_BINDING 0x020 /* Currently binding. */ #define UNP_WAITING 0x040 /* Peer state is changing. */ /* * Flags in unp_gcflag. */ #define UNPGC_DEAD 0x1 /* unpcb might be dead. */ #define UNPGC_IGNORE_RIGHTS 0x2 /* Attached rights are freed */ #define sotounpcb(so) ((struct unpcb *)((so)->so_pcb)) #endif /* _KERNEL || _WANT_UNPCB */ /* * UNPCB structure exported to user-land via sysctl(3). * * Fields prefixed with "xu_" are unique to the export structure, and fields * with "unp_" or other prefixes match corresponding fields of 'struct unpcb'. * * Legend: * (s) - used by userland utilities in src * (p) - used by utilities in ports * (3) - is known to be used by third party software not in ports * (n) - no known usage * * Evil hack: declare only if sys/socketvar.h have been included. */ #ifdef _SYS_SOCKETVAR_H_ struct xunpcb { ksize_t xu_len; /* length of this structure */ kvaddr_t xu_unpp; /* to help netstat, fstat */ kvaddr_t unp_vnode; /* (s) */ kvaddr_t unp_conn; /* (s) */ kvaddr_t xu_firstref; /* (s) */ kvaddr_t xu_nextref; /* (s) */ unp_gen_t unp_gencnt; /* (s) */ int64_t xu_spare64[8]; int32_t xu_spare32[8]; union { struct sockaddr_un xu_addr; /* our bound address */ char xu_dummy1[256]; }; union { struct sockaddr_un xu_caddr; /* their bound address */ char xu_dummy2[256]; }; struct xsocket xu_socket; } __aligned(MAX(8, sizeof(void *))); struct xunpgen { ksize_t xug_len; u_int xug_count; unp_gen_t xug_gen; so_gen_t xug_sogen; } __aligned(8); #endif /* _SYS_SOCKETVAR_H_ */ #if defined(_KERNEL) struct thread; /* In uipc_userreq.c */ void unp_copy_peercred(struct thread *td, struct unpcb *client_unp, struct unpcb *server_unp, struct unpcb *listen_unp); #endif #endif /* _SYS_UNPCB_H_ */
