2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * From: @(#)uipc_usrreq.c 8.3 (Berkeley) 1/4/94
34 * $FreeBSD: src/sys/kern/uipc_usrreq.c,v 1.54.2.10 2003/03/04 17:28:09 nectar Exp $
35 * $DragonFly: src/sys/kern/uipc_usrreq.c,v 1.44 2008/09/06 05:44:58 dillon Exp $
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/kernel.h>
41 #include <sys/domain.h>
42 #include <sys/fcntl.h>
43 #include <sys/malloc.h> /* XXX must be before <sys/file.h> */
46 #include <sys/filedesc.h>
48 #include <sys/nlookup.h>
49 #include <sys/protosw.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/resourcevar.h>
54 #include <sys/mount.h>
55 #include <sys/sysctl.h>
57 #include <sys/unpcb.h>
58 #include <sys/vnode.h>
59 #include <sys/file2.h>
60 #include <sys/spinlock2.h>
63 static MALLOC_DEFINE(M_UNPCB
, "unpcb", "unpcb struct");
64 static unp_gen_t unp_gencnt
;
65 static u_int unp_count
;
67 static struct unp_head unp_shead
, unp_dhead
;
70 * Unix communications domain.
74 * rethink name space problems
75 * need a proper out-of-band
78 static struct sockaddr sun_noname
= { sizeof(sun_noname
), AF_LOCAL
};
79 static ino_t unp_ino
= 1; /* prototype for fake inode numbers */
80 static struct spinlock unp_ino_spin
= SPINLOCK_INITIALIZER(&unp_ino_spin
);
82 static int unp_attach (struct socket
*, struct pru_attach_info
*);
83 static void unp_detach (struct unpcb
*);
84 static int unp_bind (struct unpcb
*,struct sockaddr
*, struct thread
*);
85 static int unp_connect (struct socket
*,struct sockaddr
*,
87 static void unp_disconnect (struct unpcb
*);
88 static void unp_shutdown (struct unpcb
*);
89 static void unp_drop (struct unpcb
*, int);
90 static void unp_gc (void);
91 static int unp_gc_clearmarks(struct file
*, void *);
92 static int unp_gc_checkmarks(struct file
*, void *);
93 static int unp_gc_checkrefs(struct file
*, void *);
94 static int unp_revoke_gc_check(struct file
*, void *);
95 static void unp_scan (struct mbuf
*, void (*)(struct file
*, void *),
97 static void unp_mark (struct file
*, void *data
);
98 static void unp_discard (struct file
*, void *);
99 static int unp_internalize (struct mbuf
*, struct thread
*);
100 static int unp_listen (struct unpcb
*, struct thread
*);
101 static void unp_fp_externalize(struct proc
*p
, struct file
*fp
, int fd
);
104 uipc_abort(struct socket
*so
)
106 struct unpcb
*unp
= so
->so_pcb
;
110 unp_drop(unp
, ECONNABORTED
);
117 uipc_accept(struct socket
*so
, struct sockaddr
**nam
)
119 struct unpcb
*unp
= so
->so_pcb
;
125 * Pass back name of connected socket,
126 * if it was bound and we are still connected
127 * (our peer may have closed already!).
129 if (unp
->unp_conn
&& unp
->unp_conn
->unp_addr
) {
130 *nam
= dup_sockaddr((struct sockaddr
*)unp
->unp_conn
->unp_addr
);
132 *nam
= dup_sockaddr((struct sockaddr
*)&sun_noname
);
138 uipc_attach(struct socket
*so
, int proto
, struct pru_attach_info
*ai
)
140 struct unpcb
*unp
= so
->so_pcb
;
144 return unp_attach(so
, ai
);
148 uipc_bind(struct socket
*so
, struct sockaddr
*nam
, struct thread
*td
)
150 struct unpcb
*unp
= so
->so_pcb
;
154 return unp_bind(unp
, nam
, td
);
158 uipc_connect(struct socket
*so
, struct sockaddr
*nam
, struct thread
*td
)
160 struct unpcb
*unp
= so
->so_pcb
;
164 return unp_connect(so
, nam
, td
);
168 uipc_connect2(struct socket
*so1
, struct socket
*so2
)
170 struct unpcb
*unp
= so1
->so_pcb
;
175 return unp_connect2(so1
, so2
);
178 /* control is EOPNOTSUPP */
181 uipc_detach(struct socket
*so
)
183 struct unpcb
*unp
= so
->so_pcb
;
193 uipc_disconnect(struct socket
*so
)
195 struct unpcb
*unp
= so
->so_pcb
;
204 uipc_listen(struct socket
*so
, struct thread
*td
)
206 struct unpcb
*unp
= so
->so_pcb
;
208 if (unp
== NULL
|| unp
->unp_vnode
== NULL
)
210 return unp_listen(unp
, td
);
214 uipc_peeraddr(struct socket
*so
, struct sockaddr
**nam
)
216 struct unpcb
*unp
= so
->so_pcb
;
220 if (unp
->unp_conn
&& unp
->unp_conn
->unp_addr
)
221 *nam
= dup_sockaddr((struct sockaddr
*)unp
->unp_conn
->unp_addr
);
224 * XXX: It seems that this test always fails even when
225 * connection is established. So, this else clause is
226 * added as workaround to return PF_LOCAL sockaddr.
228 *nam
= dup_sockaddr((struct sockaddr
*)&sun_noname
);
234 uipc_rcvd(struct socket
*so
, int flags
)
236 struct unpcb
*unp
= so
->so_pcb
;
241 switch (so
->so_type
) {
243 panic("uipc_rcvd DGRAM?");
248 if (unp
->unp_conn
== NULL
)
251 * Because we are transfering mbufs directly to the
252 * peer socket we have to use SSB_STOP on the sender
253 * to prevent it from building up infinite mbufs.
255 so2
= unp
->unp_conn
->unp_socket
;
256 if (so
->so_rcv
.ssb_cc
< so2
->so_snd
.ssb_hiwat
&&
257 so
->so_rcv
.ssb_mbcnt
< so2
->so_snd
.ssb_mbmax
259 so2
->so_snd
.ssb_flags
&= ~SSB_STOP
;
265 panic("uipc_rcvd unknown socktype");
270 /* pru_rcvoob is EOPNOTSUPP */
273 uipc_send(struct socket
*so
, int flags
, struct mbuf
*m
, struct sockaddr
*nam
,
274 struct mbuf
*control
, struct thread
*td
)
277 struct unpcb
*unp
= so
->so_pcb
;
284 if (flags
& PRUS_OOB
) {
289 if (control
&& (error
= unp_internalize(control
, td
)))
292 switch (so
->so_type
) {
295 struct sockaddr
*from
;
302 error
= unp_connect(so
, nam
, td
);
306 if (unp
->unp_conn
== NULL
) {
311 so2
= unp
->unp_conn
->unp_socket
;
313 from
= (struct sockaddr
*)unp
->unp_addr
;
316 if (ssb_appendaddr(&so2
->so_rcv
, from
, m
, control
)) {
330 /* Connect if not connected yet. */
332 * Note: A better implementation would complain
333 * if not equal to the peer's address.
335 if (!(so
->so_state
& SS_ISCONNECTED
)) {
337 error
= unp_connect(so
, nam
, td
);
346 if (so
->so_state
& SS_CANTSENDMORE
) {
350 if (unp
->unp_conn
== NULL
)
351 panic("uipc_send connected but no connection?");
352 so2
= unp
->unp_conn
->unp_socket
;
354 * Send to paired receive port, and then reduce
355 * send buffer hiwater marks to maintain backpressure.
359 if (ssb_appendcontrol(&so2
->so_rcv
, m
, control
)) {
363 } else if (so
->so_type
== SOCK_SEQPACKET
) {
364 sbappendrecord(&so2
->so_rcv
.sb
, m
);
367 sbappend(&so2
->so_rcv
.sb
, m
);
372 * Because we are transfering mbufs directly to the
373 * peer socket we have to use SSB_STOP on the sender
374 * to prevent it from building up infinite mbufs.
376 if (so2
->so_rcv
.ssb_cc
>= so
->so_snd
.ssb_hiwat
||
377 so2
->so_rcv
.ssb_mbcnt
>= so
->so_snd
.ssb_mbmax
379 so
->so_snd
.ssb_flags
|= SSB_STOP
;
385 panic("uipc_send unknown socktype");
389 * SEND_EOF is equivalent to a SEND followed by a SHUTDOWN.
391 if (flags
& PRUS_EOF
) {
396 if (control
&& error
!= 0)
397 unp_dispose(control
);
411 uipc_sense(struct socket
*so
, struct stat
*sb
)
413 struct unpcb
*unp
= so
->so_pcb
;
417 sb
->st_blksize
= so
->so_snd
.ssb_hiwat
;
419 if (unp
->unp_ino
== 0) { /* make up a non-zero inode number */
420 spin_lock_wr(&unp_ino_spin
);
421 unp
->unp_ino
= unp_ino
++;
422 spin_unlock_wr(&unp_ino_spin
);
424 sb
->st_ino
= unp
->unp_ino
;
429 uipc_shutdown(struct socket
*so
)
431 struct unpcb
*unp
= so
->so_pcb
;
441 uipc_sockaddr(struct socket
*so
, struct sockaddr
**nam
)
443 struct unpcb
*unp
= so
->so_pcb
;
448 *nam
= dup_sockaddr((struct sockaddr
*)unp
->unp_addr
);
452 struct pr_usrreqs uipc_usrreqs
= {
453 .pru_abort
= uipc_abort
,
454 .pru_accept
= uipc_accept
,
455 .pru_attach
= uipc_attach
,
456 .pru_bind
= uipc_bind
,
457 .pru_connect
= uipc_connect
,
458 .pru_connect2
= uipc_connect2
,
459 .pru_control
= pru_control_notsupp
,
460 .pru_detach
= uipc_detach
,
461 .pru_disconnect
= uipc_disconnect
,
462 .pru_listen
= uipc_listen
,
463 .pru_peeraddr
= uipc_peeraddr
,
464 .pru_rcvd
= uipc_rcvd
,
465 .pru_rcvoob
= pru_rcvoob_notsupp
,
466 .pru_send
= uipc_send
,
467 .pru_sense
= uipc_sense
,
468 .pru_shutdown
= uipc_shutdown
,
469 .pru_sockaddr
= uipc_sockaddr
,
470 .pru_sosend
= sosend
,
471 .pru_soreceive
= soreceive
,
476 uipc_ctloutput(struct socket
*so
, struct sockopt
*sopt
)
478 struct unpcb
*unp
= so
->so_pcb
;
481 switch (sopt
->sopt_dir
) {
483 switch (sopt
->sopt_name
) {
485 if (unp
->unp_flags
& UNP_HAVEPC
)
486 soopt_from_kbuf(sopt
, &unp
->unp_peercred
,
487 sizeof(unp
->unp_peercred
));
489 if (so
->so_type
== SOCK_STREAM
)
491 else if (so
->so_type
== SOCK_SEQPACKET
)
511 * Both send and receive buffers are allocated PIPSIZ bytes of buffering
512 * for stream sockets, although the total for sender and receiver is
513 * actually only PIPSIZ.
515 * Datagram sockets really use the sendspace as the maximum datagram size,
516 * and don't really want to reserve the sendspace. Their recvspace should
517 * be large enough for at least one max-size datagram plus address.
519 * We want the local send/recv space to be significant larger then lo0's
525 static u_long unpst_sendspace
= PIPSIZ
;
526 static u_long unpst_recvspace
= PIPSIZ
;
527 static u_long unpdg_sendspace
= 2*1024; /* really max datagram size */
528 static u_long unpdg_recvspace
= 4*1024;
530 static int unp_rights
; /* file descriptors in flight */
531 static struct spinlock unp_spin
= SPINLOCK_INITIALIZER(&unp_spin
);
533 SYSCTL_DECL(_net_local_seqpacket
);
534 SYSCTL_DECL(_net_local_stream
);
535 SYSCTL_INT(_net_local_stream
, OID_AUTO
, sendspace
, CTLFLAG_RW
,
536 &unpst_sendspace
, 0, "");
537 SYSCTL_INT(_net_local_stream
, OID_AUTO
, recvspace
, CTLFLAG_RW
,
538 &unpst_recvspace
, 0, "");
540 SYSCTL_DECL(_net_local_dgram
);
541 SYSCTL_INT(_net_local_dgram
, OID_AUTO
, maxdgram
, CTLFLAG_RW
,
542 &unpdg_sendspace
, 0, "");
543 SYSCTL_INT(_net_local_dgram
, OID_AUTO
, recvspace
, CTLFLAG_RW
,
544 &unpdg_recvspace
, 0, "");
546 SYSCTL_DECL(_net_local
);
547 SYSCTL_INT(_net_local
, OID_AUTO
, inflight
, CTLFLAG_RD
, &unp_rights
, 0, "");
550 unp_attach(struct socket
*so
, struct pru_attach_info
*ai
)
555 if (so
->so_snd
.ssb_hiwat
== 0 || so
->so_rcv
.ssb_hiwat
== 0) {
556 switch (so
->so_type
) {
560 error
= soreserve(so
, unpst_sendspace
, unpst_recvspace
,
565 error
= soreserve(so
, unpdg_sendspace
, unpdg_recvspace
,
575 unp
= kmalloc(sizeof(*unp
), M_UNPCB
, M_NOWAIT
|M_ZERO
);
578 unp
->unp_gencnt
= ++unp_gencnt
;
580 LIST_INIT(&unp
->unp_refs
);
581 unp
->unp_socket
= so
;
582 unp
->unp_rvnode
= ai
->fd_rdir
; /* jail cruft XXX JH */
583 LIST_INSERT_HEAD(so
->so_type
== SOCK_DGRAM
? &unp_dhead
584 : &unp_shead
, unp
, unp_link
);
585 so
->so_pcb
= (caddr_t
)unp
;
590 unp_detach(struct unpcb
*unp
)
592 LIST_REMOVE(unp
, unp_link
);
593 unp
->unp_gencnt
= ++unp_gencnt
;
595 if (unp
->unp_vnode
) {
596 unp
->unp_vnode
->v_socket
= NULL
;
597 vrele(unp
->unp_vnode
);
598 unp
->unp_vnode
= NULL
;
602 while (!LIST_EMPTY(&unp
->unp_refs
))
603 unp_drop(LIST_FIRST(&unp
->unp_refs
), ECONNRESET
);
604 soisdisconnected(unp
->unp_socket
);
605 unp
->unp_socket
->so_pcb
= NULL
;
608 * Normally the receive buffer is flushed later,
609 * in sofree, but if our receive buffer holds references
610 * to descriptors that are now garbage, we will dispose
611 * of those descriptor references after the garbage collector
612 * gets them (resulting in a "panic: closef: count < 0").
614 sorflush(unp
->unp_socket
);
618 kfree(unp
->unp_addr
, M_SONAME
);
623 unp_bind(struct unpcb
*unp
, struct sockaddr
*nam
, struct thread
*td
)
625 struct proc
*p
= td
->td_proc
;
626 struct sockaddr_un
*soun
= (struct sockaddr_un
*)nam
;
630 struct nlookupdata nd
;
631 char buf
[SOCK_MAXADDRLEN
];
633 if (unp
->unp_vnode
!= NULL
)
635 namelen
= soun
->sun_len
- offsetof(struct sockaddr_un
, sun_path
);
638 strncpy(buf
, soun
->sun_path
, namelen
);
639 buf
[namelen
] = 0; /* null-terminate the string */
640 error
= nlookup_init(&nd
, buf
, UIO_SYSSPACE
,
641 NLC_LOCKVP
| NLC_CREATE
| NLC_REFDVP
);
643 error
= nlookup(&nd
);
644 if (error
== 0 && nd
.nl_nch
.ncp
->nc_vp
!= NULL
)
650 vattr
.va_type
= VSOCK
;
651 vattr
.va_mode
= (ACCESSPERMS
& ~p
->p_fd
->fd_cmask
);
652 error
= VOP_NCREATE(&nd
.nl_nch
, nd
.nl_dvp
, &vp
, nd
.nl_cred
, &vattr
);
654 vp
->v_socket
= unp
->unp_socket
;
656 unp
->unp_addr
= (struct sockaddr_un
*)dup_sockaddr(nam
);
665 unp_connect(struct socket
*so
, struct sockaddr
*nam
, struct thread
*td
)
667 struct proc
*p
= td
->td_proc
;
668 struct sockaddr_un
*soun
= (struct sockaddr_un
*)nam
;
670 struct socket
*so2
, *so3
;
671 struct unpcb
*unp
, *unp2
, *unp3
;
673 struct nlookupdata nd
;
674 char buf
[SOCK_MAXADDRLEN
];
678 len
= nam
->sa_len
- offsetof(struct sockaddr_un
, sun_path
);
681 strncpy(buf
, soun
->sun_path
, len
);
685 error
= nlookup_init(&nd
, buf
, UIO_SYSSPACE
, NLC_FOLLOW
);
687 error
= nlookup(&nd
);
689 error
= cache_vget(&nd
.nl_nch
, nd
.nl_cred
, LK_EXCLUSIVE
, &vp
);
694 if (vp
->v_type
!= VSOCK
) {
698 error
= VOP_ACCESS(vp
, VWRITE
, p
->p_ucred
);
703 error
= ECONNREFUSED
;
706 if (so
->so_type
!= so2
->so_type
) {
710 if (so
->so_proto
->pr_flags
& PR_CONNREQUIRED
) {
711 if (!(so2
->so_options
& SO_ACCEPTCONN
) ||
712 (so3
= sonewconn(so2
, 0)) == NULL
) {
713 error
= ECONNREFUSED
;
720 unp3
->unp_addr
= (struct sockaddr_un
*)
721 dup_sockaddr((struct sockaddr
*)unp2
->unp_addr
);
724 * unp_peercred management:
726 * The connecter's (client's) credentials are copied
727 * from its process structure at the time of connect()
730 cru2x(p
->p_ucred
, &unp3
->unp_peercred
);
731 unp3
->unp_flags
|= UNP_HAVEPC
;
733 * The receiver's (server's) credentials are copied
734 * from the unp_peercred member of socket on which the
735 * former called listen(); unp_listen() cached that
736 * process's credentials at that time so we can use
739 KASSERT(unp2
->unp_flags
& UNP_HAVEPCCACHED
,
740 ("unp_connect: listener without cached peercred"));
741 memcpy(&unp
->unp_peercred
, &unp2
->unp_peercred
,
742 sizeof(unp
->unp_peercred
));
743 unp
->unp_flags
|= UNP_HAVEPC
;
747 error
= unp_connect2(so
, so2
);
754 unp_connect2(struct socket
*so
, struct socket
*so2
)
756 struct unpcb
*unp
= so
->so_pcb
;
759 if (so2
->so_type
!= so
->so_type
)
762 unp
->unp_conn
= unp2
;
763 switch (so
->so_type
) {
766 LIST_INSERT_HEAD(&unp2
->unp_refs
, unp
, unp_reflink
);
772 unp2
->unp_conn
= unp
;
778 panic("unp_connect2");
784 unp_disconnect(struct unpcb
*unp
)
786 struct unpcb
*unp2
= unp
->unp_conn
;
791 unp
->unp_conn
= NULL
;
793 switch (unp
->unp_socket
->so_type
) {
795 LIST_REMOVE(unp
, unp_reflink
);
796 unp
->unp_socket
->so_state
&= ~SS_ISCONNECTED
;
800 soisdisconnected(unp
->unp_socket
);
801 unp2
->unp_conn
= NULL
;
802 soisdisconnected(unp2
->unp_socket
);
809 unp_abort(struct unpcb
*unp
)
817 prison_unpcb(struct thread
*td
, struct unpcb
*unp
)
823 if ((p
= td
->td_proc
) == NULL
)
825 if (!p
->p_ucred
->cr_prison
)
827 if (p
->p_fd
->fd_rdir
== unp
->unp_rvnode
)
833 unp_pcblist(SYSCTL_HANDLER_ARGS
)
836 struct unpcb
*unp
, **unp_list
;
838 struct unp_head
*head
;
840 head
= ((intptr_t)arg1
== SOCK_DGRAM
? &unp_dhead
: &unp_shead
);
842 KKASSERT(curproc
!= NULL
);
845 * The process of preparing the PCB list is too time-consuming and
846 * resource-intensive to repeat twice on every request.
848 if (req
->oldptr
== NULL
) {
850 req
->oldidx
= (n
+ n
/8) * sizeof(struct xunpcb
);
854 if (req
->newptr
!= NULL
)
858 * OK, now we're committed to doing something.
863 unp_list
= kmalloc(n
* sizeof *unp_list
, M_TEMP
, M_WAITOK
);
865 for (unp
= LIST_FIRST(head
), i
= 0; unp
&& i
< n
;
866 unp
= LIST_NEXT(unp
, unp_link
)) {
867 if (unp
->unp_gencnt
<= gencnt
&& !prison_unpcb(req
->td
, unp
))
870 n
= i
; /* in case we lost some during malloc */
873 for (i
= 0; i
< n
; i
++) {
875 if (unp
->unp_gencnt
<= gencnt
) {
877 xu
.xu_len
= sizeof xu
;
880 * XXX - need more locking here to protect against
881 * connect/disconnect races for SMP.
884 bcopy(unp
->unp_addr
, &xu
.xu_addr
,
885 unp
->unp_addr
->sun_len
);
886 if (unp
->unp_conn
&& unp
->unp_conn
->unp_addr
)
887 bcopy(unp
->unp_conn
->unp_addr
,
889 unp
->unp_conn
->unp_addr
->sun_len
);
890 bcopy(unp
, &xu
.xu_unp
, sizeof *unp
);
891 sotoxsocket(unp
->unp_socket
, &xu
.xu_socket
);
892 error
= SYSCTL_OUT(req
, &xu
, sizeof xu
);
895 kfree(unp_list
, M_TEMP
);
899 SYSCTL_PROC(_net_local_dgram
, OID_AUTO
, pcblist
, CTLFLAG_RD
,
900 (caddr_t
)(long)SOCK_DGRAM
, 0, unp_pcblist
, "S,xunpcb",
901 "List of active local datagram sockets");
902 SYSCTL_PROC(_net_local_stream
, OID_AUTO
, pcblist
, CTLFLAG_RD
,
903 (caddr_t
)(long)SOCK_STREAM
, 0, unp_pcblist
, "S,xunpcb",
904 "List of active local stream sockets");
905 SYSCTL_PROC(_net_local_seqpacket
, OID_AUTO
, pcblist
, CTLFLAG_RD
,
906 (caddr_t
)(long)SOCK_SEQPACKET
, 0, unp_pcblist
, "S,xunpcb",
907 "List of active local seqpacket stream sockets");
910 unp_shutdown(struct unpcb
*unp
)
914 if ((unp
->unp_socket
->so_type
== SOCK_STREAM
||
915 unp
->unp_socket
->so_type
== SOCK_SEQPACKET
) &&
916 unp
->unp_conn
!= NULL
&& (so
= unp
->unp_conn
->unp_socket
)) {
922 unp_drop(struct unpcb
*unp
, int err
)
924 struct socket
*so
= unp
->unp_socket
;
939 unp_externalize(struct mbuf
*rights
)
941 struct proc
*p
= curproc
; /* XXX */
943 struct cmsghdr
*cm
= mtod(rights
, struct cmsghdr
*);
947 int newfds
= (cm
->cmsg_len
- (CMSG_DATA(cm
) - (u_char
*)cm
))
948 / sizeof (struct file
*);
952 * if the new FD's will not fit, then we free them all
954 if (!fdavail(p
, newfds
)) {
955 rp
= (struct file
**)CMSG_DATA(cm
);
956 for (i
= 0; i
< newfds
; i
++) {
959 * zero the pointer before calling unp_discard,
960 * since it may end up in unp_gc()..
963 unp_discard(fp
, NULL
);
969 * now change each pointer to an fd in the global table to
970 * an integer that is the index to the local fd table entry
971 * that we set up to point to the global one we are transferring.
972 * If sizeof (struct file *) is bigger than or equal to sizeof int,
973 * then do it in forward order. In that case, an integer will
974 * always come in the same place or before its corresponding
975 * struct file pointer.
976 * If sizeof (struct file *) is smaller than sizeof int, then
977 * do it in reverse order.
979 if (sizeof (struct file
*) >= sizeof (int)) {
980 fdp
= (int *)CMSG_DATA(cm
);
981 rp
= (struct file
**)CMSG_DATA(cm
);
982 for (i
= 0; i
< newfds
; i
++) {
983 if (fdalloc(p
, 0, &f
))
984 panic("unp_externalize");
986 unp_fp_externalize(p
, fp
, f
);
990 fdp
= (int *)CMSG_DATA(cm
) + newfds
- 1;
991 rp
= (struct file
**)CMSG_DATA(cm
) + newfds
- 1;
992 for (i
= 0; i
< newfds
; i
++) {
993 if (fdalloc(p
, 0, &f
))
994 panic("unp_externalize");
996 unp_fp_externalize(p
, fp
, f
);
1002 * Adjust length, in case sizeof(struct file *) and sizeof(int)
1005 cm
->cmsg_len
= CMSG_LEN(newfds
* sizeof(int));
1006 rights
->m_len
= cm
->cmsg_len
;
1011 unp_fp_externalize(struct proc
*p
, struct file
*fp
, int fd
)
1018 if (fp
->f_flag
& FREVOKED
) {
1019 kprintf("Warning: revoked fp exiting unix socket\n");
1021 error
= falloc(p
, &fx
, NULL
);
1025 fsetfd(p
, NULL
, fd
);
1031 spin_lock_wr(&unp_spin
);
1034 spin_unlock_wr(&unp_spin
);
1042 LIST_INIT(&unp_dhead
);
1043 LIST_INIT(&unp_shead
);
1044 spin_init(&unp_spin
);
1048 unp_internalize(struct mbuf
*control
, struct thread
*td
)
1050 struct proc
*p
= td
->td_proc
;
1051 struct filedesc
*fdescp
;
1052 struct cmsghdr
*cm
= mtod(control
, struct cmsghdr
*);
1056 struct cmsgcred
*cmcred
;
1062 if ((cm
->cmsg_type
!= SCM_RIGHTS
&& cm
->cmsg_type
!= SCM_CREDS
) ||
1063 cm
->cmsg_level
!= SOL_SOCKET
||
1064 CMSG_ALIGN(cm
->cmsg_len
) != control
->m_len
) {
1069 * Fill in credential information.
1071 if (cm
->cmsg_type
== SCM_CREDS
) {
1072 cmcred
= (struct cmsgcred
*)CMSG_DATA(cm
);
1073 cmcred
->cmcred_pid
= p
->p_pid
;
1074 cmcred
->cmcred_uid
= p
->p_ucred
->cr_ruid
;
1075 cmcred
->cmcred_gid
= p
->p_ucred
->cr_rgid
;
1076 cmcred
->cmcred_euid
= p
->p_ucred
->cr_uid
;
1077 cmcred
->cmcred_ngroups
= MIN(p
->p_ucred
->cr_ngroups
,
1079 for (i
= 0; i
< cmcred
->cmcred_ngroups
; i
++)
1080 cmcred
->cmcred_groups
[i
] = p
->p_ucred
->cr_groups
[i
];
1085 * cmsghdr may not be aligned, do not allow calculation(s) to
1088 if (cm
->cmsg_len
< CMSG_LEN(0))
1091 oldfds
= (cm
->cmsg_len
- CMSG_LEN(0)) / sizeof (int);
1094 * check that all the FDs passed in refer to legal OPEN files
1095 * If not, reject the entire operation.
1097 fdp
= (int *)CMSG_DATA(cm
);
1098 for (i
= 0; i
< oldfds
; i
++) {
1100 if ((unsigned)fd
>= fdescp
->fd_nfiles
||
1101 fdescp
->fd_files
[fd
].fp
== NULL
)
1103 if (fdescp
->fd_files
[fd
].fp
->f_type
== DTYPE_KQUEUE
)
1104 return (EOPNOTSUPP
);
1107 * Now replace the integer FDs with pointers to
1108 * the associated global file table entry..
1109 * Allocate a bigger buffer as necessary. But if an cluster is not
1110 * enough, return E2BIG.
1112 newlen
= CMSG_LEN(oldfds
* sizeof(struct file
*));
1113 if (newlen
> MCLBYTES
)
1115 if (newlen
- control
->m_len
> M_TRAILINGSPACE(control
)) {
1116 if (control
->m_flags
& M_EXT
)
1118 MCLGET(control
, MB_WAIT
);
1119 if (!(control
->m_flags
& M_EXT
))
1122 /* copy the data to the cluster */
1123 memcpy(mtod(control
, char *), cm
, cm
->cmsg_len
);
1124 cm
= mtod(control
, struct cmsghdr
*);
1128 * Adjust length, in case sizeof(struct file *) and sizeof(int)
1131 cm
->cmsg_len
= newlen
;
1132 control
->m_len
= CMSG_ALIGN(newlen
);
1135 * Transform the file descriptors into struct file pointers.
1136 * If sizeof (struct file *) is bigger than or equal to sizeof int,
1137 * then do it in reverse order so that the int won't get until
1139 * If sizeof (struct file *) is smaller than sizeof int, then
1140 * do it in forward order.
1142 if (sizeof (struct file
*) >= sizeof (int)) {
1143 fdp
= (int *)CMSG_DATA(cm
) + oldfds
- 1;
1144 rp
= (struct file
**)CMSG_DATA(cm
) + oldfds
- 1;
1145 for (i
= 0; i
< oldfds
; i
++) {
1146 fp
= fdescp
->fd_files
[*fdp
--].fp
;
1149 spin_lock_wr(&unp_spin
);
1152 spin_unlock_wr(&unp_spin
);
1155 fdp
= (int *)CMSG_DATA(cm
);
1156 rp
= (struct file
**)CMSG_DATA(cm
);
1157 for (i
= 0; i
< oldfds
; i
++) {
1158 fp
= fdescp
->fd_files
[*fdp
++].fp
;
1161 spin_lock_wr(&unp_spin
);
1164 spin_unlock_wr(&unp_spin
);
1171 * Garbage collect in-transit file descriptors that get lost due to
1172 * loops (i.e. when a socket is sent to another process over itself,
1173 * and more complex situations).
1175 * NOT MPSAFE - TODO socket flush code and maybe closef. Rest is MPSAFE.
1178 struct unp_gc_info
{
1179 struct file
**extra_ref
;
1180 struct file
*locked_fp
;
1189 struct unp_gc_info info
;
1190 static boolean_t unp_gcing
;
1194 spin_lock_wr(&unp_spin
);
1196 spin_unlock_wr(&unp_spin
);
1200 spin_unlock_wr(&unp_spin
);
1203 * before going through all this, set all FDs to
1204 * be NOT defered and NOT externally accessible
1207 allfiles_scan_exclusive(unp_gc_clearmarks
, NULL
);
1209 allfiles_scan_exclusive(unp_gc_checkmarks
, &info
);
1210 } while (info
.defer
);
1213 * We grab an extra reference to each of the file table entries
1214 * that are not otherwise accessible and then free the rights
1215 * that are stored in messages on them.
1217 * The bug in the orginal code is a little tricky, so I'll describe
1218 * what's wrong with it here.
1220 * It is incorrect to simply unp_discard each entry for f_msgcount
1221 * times -- consider the case of sockets A and B that contain
1222 * references to each other. On a last close of some other socket,
1223 * we trigger a gc since the number of outstanding rights (unp_rights)
1224 * is non-zero. If during the sweep phase the gc code un_discards,
1225 * we end up doing a (full) closef on the descriptor. A closef on A
1226 * results in the following chain. Closef calls soo_close, which
1227 * calls soclose. Soclose calls first (through the switch
1228 * uipc_usrreq) unp_detach, which re-invokes unp_gc. Unp_gc simply
1229 * returns because the previous instance had set unp_gcing, and
1230 * we return all the way back to soclose, which marks the socket
1231 * with SS_NOFDREF, and then calls sofree. Sofree calls sorflush
1232 * to free up the rights that are queued in messages on the socket A,
1233 * i.e., the reference on B. The sorflush calls via the dom_dispose
1234 * switch unp_dispose, which unp_scans with unp_discard. This second
1235 * instance of unp_discard just calls closef on B.
1237 * Well, a similar chain occurs on B, resulting in a sorflush on B,
1238 * which results in another closef on A. Unfortunately, A is already
1239 * being closed, and the descriptor has already been marked with
1240 * SS_NOFDREF, and soclose panics at this point.
1242 * Here, we first take an extra reference to each inaccessible
1243 * descriptor. Then, we call sorflush ourself, since we know
1244 * it is a Unix domain socket anyhow. After we destroy all the
1245 * rights carried in messages, we do a last closef to get rid
1246 * of our extra reference. This is the last close, and the
1247 * unp_detach etc will shut down the socket.
1249 * 91/09/19, bsy@cs.cmu.edu
1251 info
.extra_ref
= kmalloc(256 * sizeof(struct file
*), M_FILE
, M_WAITOK
);
1252 info
.maxindex
= 256;
1259 allfiles_scan_exclusive(unp_gc_checkrefs
, &info
);
1262 * For each FD on our hit list, do the following two things
1264 for (i
= info
.index
, fpp
= info
.extra_ref
; --i
>= 0; ++fpp
) {
1265 struct file
*tfp
= *fpp
;
1266 if (tfp
->f_type
== DTYPE_SOCKET
&& tfp
->f_data
!= NULL
)
1267 sorflush((struct socket
*)(tfp
->f_data
));
1269 for (i
= info
.index
, fpp
= info
.extra_ref
; --i
>= 0; ++fpp
)
1271 } while (info
.index
== info
.maxindex
);
1272 kfree((caddr_t
)info
.extra_ref
, M_FILE
);
1277 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry
1280 unp_gc_checkrefs(struct file
*fp
, void *data
)
1282 struct unp_gc_info
*info
= data
;
1284 if (fp
->f_count
== 0)
1286 if (info
->index
== info
->maxindex
)
1290 * If all refs are from msgs, and it's not marked accessible
1291 * then it must be referenced from some unreachable cycle
1292 * of (shut-down) FDs, so include it in our
1293 * list of FDs to remove
1295 if (fp
->f_count
== fp
->f_msgcount
&& !(fp
->f_flag
& FMARK
)) {
1296 info
->extra_ref
[info
->index
++] = fp
;
1303 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry
1306 unp_gc_clearmarks(struct file
*fp
, void *data __unused
)
1308 atomic_clear_int(&fp
->f_flag
, FMARK
| FDEFER
);
1313 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry
1316 unp_gc_checkmarks(struct file
*fp
, void *data
)
1318 struct unp_gc_info
*info
= data
;
1322 * If the file is not open, skip it
1324 if (fp
->f_count
== 0)
1327 * If we already marked it as 'defer' in a
1328 * previous pass, then try process it this time
1331 if (fp
->f_flag
& FDEFER
) {
1332 atomic_clear_int(&fp
->f_flag
, FDEFER
);
1336 * if it's not defered, then check if it's
1337 * already marked.. if so skip it
1339 if (fp
->f_flag
& FMARK
)
1342 * If all references are from messages
1343 * in transit, then skip it. it's not
1344 * externally accessible.
1346 if (fp
->f_count
== fp
->f_msgcount
)
1349 * If it got this far then it must be
1350 * externally accessible.
1352 atomic_set_int(&fp
->f_flag
, FMARK
);
1356 * either it was defered, or it is externally
1357 * accessible and not already marked so.
1358 * Now check if it is possibly one of OUR sockets.
1360 if (fp
->f_type
!= DTYPE_SOCKET
||
1361 (so
= (struct socket
*)fp
->f_data
) == NULL
)
1363 if (so
->so_proto
->pr_domain
!= &localdomain
||
1364 !(so
->so_proto
->pr_flags
& PR_RIGHTS
))
1367 if (so
->so_rcv
.ssb_flags
& SSB_LOCK
) {
1369 * This is problematical; it's not clear
1370 * we need to wait for the sockbuf to be
1371 * unlocked (on a uniprocessor, at least),
1372 * and it's also not clear what to do
1373 * if sbwait returns an error due to receipt
1374 * of a signal. If sbwait does return
1375 * an error, we'll go into an infinite
1376 * loop. Delete all of this for now.
1378 sbwait(&so
->so_rcv
);
1383 * So, Ok, it's one of our sockets and it IS externally
1384 * accessible (or was defered). Now we look
1385 * to see if we hold any file descriptors in its
1386 * message buffers. Follow those links and mark them
1387 * as accessible too.
1389 info
->locked_fp
= fp
;
1390 /* spin_lock_wr(&so->so_rcv.sb_spin); */
1391 unp_scan(so
->so_rcv
.ssb_mb
, unp_mark
, info
);
1392 /* spin_unlock_wr(&so->so_rcv.sb_spin);*/
1397 * Scan all unix domain sockets and replace any revoked file pointers
1398 * found with the dummy file pointer fx. We don't worry about races
1399 * against file pointers being read out as those are handled in the
1403 #define REVOKE_GC_MAXFILES 32
1405 struct unp_revoke_gc_info
{
1407 struct file
*fary
[REVOKE_GC_MAXFILES
];
1412 unp_revoke_gc(struct file
*fx
)
1414 struct unp_revoke_gc_info info
;
1420 allfiles_scan_exclusive(unp_revoke_gc_check
, &info
);
1421 for (i
= 0; i
< info
.fcount
; ++i
)
1422 unp_fp_externalize(NULL
, info
.fary
[i
], -1);
1423 } while (info
.fcount
== REVOKE_GC_MAXFILES
);
1427 * Check for and replace revoked descriptors.
1429 * WARNING: This routine is not allowed to block.
1432 unp_revoke_gc_check(struct file
*fps
, void *vinfo
)
1434 struct unp_revoke_gc_info
*info
= vinfo
;
1445 * Is this a unix domain socket with rights-passing abilities?
1447 if (fps
->f_type
!= DTYPE_SOCKET
)
1449 if ((so
= (struct socket
*)fps
->f_data
) == NULL
)
1451 if (so
->so_proto
->pr_domain
!= &localdomain
)
1453 if ((so
->so_proto
->pr_flags
& PR_RIGHTS
) == 0)
1457 * Scan the mbufs for control messages and replace any revoked
1458 * descriptors we find.
1460 m0
= so
->so_rcv
.ssb_mb
;
1462 for (m
= m0
; m
; m
= m
->m_next
) {
1463 if (m
->m_type
!= MT_CONTROL
)
1465 if (m
->m_len
< sizeof(*cm
))
1467 cm
= mtod(m
, struct cmsghdr
*);
1468 if (cm
->cmsg_level
!= SOL_SOCKET
||
1469 cm
->cmsg_type
!= SCM_RIGHTS
) {
1472 qfds
= (cm
->cmsg_len
- CMSG_LEN(0)) / sizeof(void *);
1473 rp
= (struct file
**)CMSG_DATA(cm
);
1474 for (i
= 0; i
< qfds
; i
++) {
1476 if (fp
->f_flag
& FREVOKED
) {
1477 kprintf("Warning: Removing revoked fp from unix domain socket queue\n");
1479 info
->fx
->f_msgcount
++;
1482 info
->fary
[info
->fcount
++] = fp
;
1484 if (info
->fcount
== REVOKE_GC_MAXFILES
)
1487 if (info
->fcount
== REVOKE_GC_MAXFILES
)
1491 if (info
->fcount
== REVOKE_GC_MAXFILES
)
1496 * Stop the scan if we filled up our array.
1498 if (info
->fcount
== REVOKE_GC_MAXFILES
)
1504 unp_dispose(struct mbuf
*m
)
1507 unp_scan(m
, unp_discard
, NULL
);
1511 unp_listen(struct unpcb
*unp
, struct thread
*td
)
1513 struct proc
*p
= td
->td_proc
;
1516 cru2x(p
->p_ucred
, &unp
->unp_peercred
);
1517 unp
->unp_flags
|= UNP_HAVEPCCACHED
;
1522 unp_scan(struct mbuf
*m0
, void (*op
)(struct file
*, void *), void *data
)
1531 for (m
= m0
; m
; m
= m
->m_next
) {
1532 if (m
->m_type
== MT_CONTROL
&&
1533 m
->m_len
>= sizeof(*cm
)) {
1534 cm
= mtod(m
, struct cmsghdr
*);
1535 if (cm
->cmsg_level
!= SOL_SOCKET
||
1536 cm
->cmsg_type
!= SCM_RIGHTS
)
1538 qfds
= (cm
->cmsg_len
- CMSG_LEN(0)) /
1540 rp
= (struct file
**)CMSG_DATA(cm
);
1541 for (i
= 0; i
< qfds
; i
++)
1543 break; /* XXX, but saves time */
1551 unp_mark(struct file
*fp
, void *data
)
1553 struct unp_gc_info
*info
= data
;
1555 if ((fp
->f_flag
& FMARK
) == 0) {
1557 atomic_set_int(&fp
->f_flag
, FMARK
| FDEFER
);
1562 unp_discard(struct file
*fp
, void *data __unused
)
1564 spin_lock_wr(&unp_spin
);
1567 spin_unlock_wr(&unp_spin
);