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 1.23 2006/05/05 21:15:09 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>
61 #include <vm/vm_zone.h>
63 static struct vm_zone *unp_zone;
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; /* prototype for fake inode numbers */
81 static int unp_attach (struct socket *, struct pru_attach_info *);
82 static void unp_detach (struct unpcb *);
83 static int unp_bind (struct unpcb *,struct sockaddr *, struct thread *);
84 static int unp_connect (struct socket *,struct sockaddr *,
86 static void unp_disconnect (struct unpcb *);
87 static void unp_shutdown (struct unpcb *);
88 static void unp_drop (struct unpcb *, int);
89 static void unp_gc (void);
90 static void unp_scan (struct mbuf *, void (*)(struct file *));
91 static void unp_mark (struct file *);
92 static void unp_discard (struct file *);
93 static int unp_internalize (struct mbuf *, struct thread *);
94 static int unp_listen (struct unpcb *, struct thread *);
97 uipc_abort(struct socket *so)
99 struct unpcb *unp = so->so_pcb;
103 unp_drop(unp, ECONNABORTED);
110 uipc_accept(struct socket *so, struct sockaddr **nam)
112 struct unpcb *unp = so->so_pcb;
118 * Pass back name of connected socket,
119 * if it was bound and we are still connected
120 * (our peer may have closed already!).
122 if (unp->unp_conn && unp->unp_conn->unp_addr) {
123 *nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr);
125 *nam = dup_sockaddr((struct sockaddr *)&sun_noname);
131 uipc_attach(struct socket *so, int proto, struct pru_attach_info *ai)
133 struct unpcb *unp = so->so_pcb;
137 return unp_attach(so, ai);
141 uipc_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
143 struct unpcb *unp = so->so_pcb;
147 return unp_bind(unp, nam, td);
151 uipc_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
153 struct unpcb *unp = so->so_pcb;
157 return unp_connect(so, nam, td);
161 uipc_connect2(struct socket *so1, struct socket *so2)
163 struct unpcb *unp = so1->so_pcb;
168 return unp_connect2(so1, so2);
171 /* control is EOPNOTSUPP */
174 uipc_detach(struct socket *so)
176 struct unpcb *unp = so->so_pcb;
186 uipc_disconnect(struct socket *so)
188 struct unpcb *unp = so->so_pcb;
197 uipc_listen(struct socket *so, struct thread *td)
199 struct unpcb *unp = so->so_pcb;
201 if (unp == NULL || unp->unp_vnode == NULL)
203 return unp_listen(unp, td);
207 uipc_peeraddr(struct socket *so, struct sockaddr **nam)
209 struct unpcb *unp = so->so_pcb;
213 if (unp->unp_conn && unp->unp_conn->unp_addr)
214 *nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr);
217 * XXX: It seems that this test always fails even when
218 * connection is established. So, this else clause is
219 * added as workaround to return PF_LOCAL sockaddr.
221 *nam = dup_sockaddr((struct sockaddr *)&sun_noname);
227 uipc_rcvd(struct socket *so, int flags)
229 struct unpcb *unp = so->so_pcb;
235 switch (so->so_type) {
237 panic("uipc_rcvd DGRAM?");
241 if (unp->unp_conn == NULL)
243 so2 = unp->unp_conn->unp_socket;
245 * Adjust backpressure on sender
246 * and wakeup any waiting to write.
248 so2->so_snd.sb_mbmax += unp->unp_mbcnt - so->so_rcv.sb_mbcnt;
249 unp->unp_mbcnt = so->so_rcv.sb_mbcnt;
251 so2->so_snd.sb_hiwat + unp->unp_cc - so->so_rcv.sb_cc;
252 chgsbsize(so2->so_cred->cr_uidinfo, &so2->so_snd.sb_hiwat,
253 newhiwat, RLIM_INFINITY);
254 unp->unp_cc = so->so_rcv.sb_cc;
259 panic("uipc_rcvd unknown socktype");
264 /* pru_rcvoob is EOPNOTSUPP */
267 uipc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
268 struct mbuf *control, struct thread *td)
271 struct unpcb *unp = so->so_pcb;
279 if (flags & PRUS_OOB) {
284 if (control && (error = unp_internalize(control, td)))
287 switch (so->so_type) {
290 struct sockaddr *from;
297 error = unp_connect(so, nam, td);
301 if (unp->unp_conn == NULL) {
306 so2 = unp->unp_conn->unp_socket;
308 from = (struct sockaddr *)unp->unp_addr;
311 if (sbappendaddr(&so2->so_rcv, from, m, control)) {
323 /* Connect if not connected yet. */
325 * Note: A better implementation would complain
326 * if not equal to the peer's address.
328 if (!(so->so_state & SS_ISCONNECTED)) {
330 error = unp_connect(so, nam, td);
339 if (so->so_state & SS_CANTSENDMORE) {
343 if (unp->unp_conn == NULL)
344 panic("uipc_send connected but no connection?");
345 so2 = unp->unp_conn->unp_socket;
347 * Send to paired receive port, and then reduce
348 * send buffer hiwater marks to maintain backpressure.
352 if (sbappendcontrol(&so2->so_rcv, m, control))
355 sbappend(&so2->so_rcv, m);
356 so->so_snd.sb_mbmax -=
357 so2->so_rcv.sb_mbcnt - unp->unp_conn->unp_mbcnt;
358 unp->unp_conn->unp_mbcnt = so2->so_rcv.sb_mbcnt;
359 newhiwat = so->so_snd.sb_hiwat -
360 (so2->so_rcv.sb_cc - unp->unp_conn->unp_cc);
361 chgsbsize(so->so_cred->cr_uidinfo, &so->so_snd.sb_hiwat,
362 newhiwat, RLIM_INFINITY);
363 unp->unp_conn->unp_cc = so2->so_rcv.sb_cc;
369 panic("uipc_send unknown socktype");
373 * SEND_EOF is equivalent to a SEND followed by a SHUTDOWN.
375 if (flags & PRUS_EOF) {
380 if (control && error != 0)
381 unp_dispose(control);
392 uipc_sense(struct socket *so, struct stat *sb)
394 struct unpcb *unp = so->so_pcb;
399 sb->st_blksize = so->so_snd.sb_hiwat;
400 if (so->so_type == SOCK_STREAM && unp->unp_conn != NULL) {
401 so2 = unp->unp_conn->unp_socket;
402 sb->st_blksize += so2->so_rcv.sb_cc;
405 if (unp->unp_ino == 0) /* make up a non-zero inode number */
406 unp->unp_ino = (++unp_ino == 0) ? ++unp_ino : unp_ino;
407 sb->st_ino = unp->unp_ino;
412 uipc_shutdown(struct socket *so)
414 struct unpcb *unp = so->so_pcb;
424 uipc_sockaddr(struct socket *so, struct sockaddr **nam)
426 struct unpcb *unp = so->so_pcb;
431 *nam = dup_sockaddr((struct sockaddr *)unp->unp_addr);
435 struct pr_usrreqs uipc_usrreqs = {
436 uipc_abort, uipc_accept, uipc_attach, uipc_bind, uipc_connect,
437 uipc_connect2, pru_control_notsupp, uipc_detach, uipc_disconnect,
438 uipc_listen, uipc_peeraddr, uipc_rcvd, pru_rcvoob_notsupp,
439 uipc_send, uipc_sense, uipc_shutdown, uipc_sockaddr,
440 sosend, soreceive, sopoll
444 uipc_ctloutput(struct socket *so, struct sockopt *sopt)
446 struct unpcb *unp = so->so_pcb;
449 switch (sopt->sopt_dir) {
451 switch (sopt->sopt_name) {
453 if (unp->unp_flags & UNP_HAVEPC)
454 error = sooptcopyout(sopt, &unp->unp_peercred,
455 sizeof(unp->unp_peercred));
457 if (so->so_type == SOCK_STREAM)
477 * Both send and receive buffers are allocated PIPSIZ bytes of buffering
478 * for stream sockets, although the total for sender and receiver is
479 * actually only PIPSIZ.
480 * Datagram sockets really use the sendspace as the maximum datagram size,
481 * and don't really want to reserve the sendspace. Their recvspace should
482 * be large enough for at least one max-size datagram plus address.
487 static u_long unpst_sendspace = PIPSIZ;
488 static u_long unpst_recvspace = PIPSIZ;
489 static u_long unpdg_sendspace = 2*1024; /* really max datagram size */
490 static u_long unpdg_recvspace = 4*1024;
492 static int unp_rights; /* file descriptors in flight */
494 SYSCTL_DECL(_net_local_stream);
495 SYSCTL_INT(_net_local_stream, OID_AUTO, sendspace, CTLFLAG_RW,
496 &unpst_sendspace, 0, "");
497 SYSCTL_INT(_net_local_stream, OID_AUTO, recvspace, CTLFLAG_RW,
498 &unpst_recvspace, 0, "");
500 SYSCTL_DECL(_net_local_dgram);
501 SYSCTL_INT(_net_local_dgram, OID_AUTO, maxdgram, CTLFLAG_RW,
502 &unpdg_sendspace, 0, "");
503 SYSCTL_INT(_net_local_dgram, OID_AUTO, recvspace, CTLFLAG_RW,
504 &unpdg_recvspace, 0, "");
506 SYSCTL_DECL(_net_local);
507 SYSCTL_INT(_net_local, OID_AUTO, inflight, CTLFLAG_RD, &unp_rights, 0, "");
510 unp_attach(struct socket *so, struct pru_attach_info *ai)
515 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
516 switch (so->so_type) {
519 error = soreserve(so, unpst_sendspace, unpst_recvspace,
524 error = soreserve(so, unpdg_sendspace, unpdg_recvspace,
534 unp = zalloc(unp_zone);
537 bzero(unp, sizeof *unp);
538 unp->unp_gencnt = ++unp_gencnt;
540 LIST_INIT(&unp->unp_refs);
541 unp->unp_socket = so;
542 unp->unp_rvnode = ai->fd_rdir; /* jail cruft XXX JH */
543 LIST_INSERT_HEAD(so->so_type == SOCK_DGRAM ? &unp_dhead
544 : &unp_shead, unp, unp_link);
545 so->so_pcb = (caddr_t)unp;
550 unp_detach(struct unpcb *unp)
552 LIST_REMOVE(unp, unp_link);
553 unp->unp_gencnt = ++unp_gencnt;
555 if (unp->unp_vnode) {
556 unp->unp_vnode->v_socket = NULL;
557 vrele(unp->unp_vnode);
558 unp->unp_vnode = NULL;
562 while (!LIST_EMPTY(&unp->unp_refs))
563 unp_drop(LIST_FIRST(&unp->unp_refs), ECONNRESET);
564 soisdisconnected(unp->unp_socket);
565 unp->unp_socket->so_pcb = NULL;
568 * Normally the receive buffer is flushed later,
569 * in sofree, but if our receive buffer holds references
570 * to descriptors that are now garbage, we will dispose
571 * of those descriptor references after the garbage collector
572 * gets them (resulting in a "panic: closef: count < 0").
574 sorflush(unp->unp_socket);
578 free(unp->unp_addr, M_SONAME);
579 zfree(unp_zone, unp);
583 unp_bind(struct unpcb *unp, struct sockaddr *nam, struct thread *td)
585 struct proc *p = td->td_proc;
586 struct sockaddr_un *soun = (struct sockaddr_un *)nam;
590 struct nlookupdata nd;
591 char buf[SOCK_MAXADDRLEN];
593 if (unp->unp_vnode != NULL)
595 namelen = soun->sun_len - offsetof(struct sockaddr_un, sun_path);
598 strncpy(buf, soun->sun_path, namelen);
599 buf[namelen] = 0; /* null-terminate the string */
600 error = nlookup_init(&nd, buf, UIO_SYSSPACE, NLC_LOCKVP|NLC_CREATE);
602 error = nlookup(&nd);
603 if (error == 0 && nd.nl_ncp->nc_vp != NULL)
609 vattr.va_type = VSOCK;
610 vattr.va_mode = (ACCESSPERMS & ~p->p_fd->fd_cmask);
611 error = VOP_NCREATE(nd.nl_ncp, &vp, nd.nl_cred, &vattr);
613 vp->v_socket = unp->unp_socket;
615 unp->unp_addr = (struct sockaddr_un *)dup_sockaddr(nam);
624 unp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
626 struct proc *p = td->td_proc;
627 struct sockaddr_un *soun = (struct sockaddr_un *)nam;
629 struct socket *so2, *so3;
630 struct unpcb *unp, *unp2, *unp3;
632 struct nlookupdata nd;
633 char buf[SOCK_MAXADDRLEN];
637 len = nam->sa_len - offsetof(struct sockaddr_un, sun_path);
640 strncpy(buf, soun->sun_path, len);
644 error = nlookup_init(&nd, buf, UIO_SYSSPACE, NLC_FOLLOW);
646 error = nlookup(&nd);
648 error = cache_vget(nd.nl_ncp, nd.nl_cred, LK_EXCLUSIVE, &vp);
653 if (vp->v_type != VSOCK) {
657 error = VOP_ACCESS(vp, VWRITE, p->p_ucred, td);
662 error = ECONNREFUSED;
665 if (so->so_type != so2->so_type) {
669 if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
670 if (!(so2->so_options & SO_ACCEPTCONN) ||
671 (so3 = sonewconn(so2, 0)) == NULL) {
672 error = ECONNREFUSED;
679 unp3->unp_addr = (struct sockaddr_un *)
680 dup_sockaddr((struct sockaddr *)unp2->unp_addr);
683 * unp_peercred management:
685 * The connecter's (client's) credentials are copied
686 * from its process structure at the time of connect()
689 cru2x(p->p_ucred, &unp3->unp_peercred);
690 unp3->unp_flags |= UNP_HAVEPC;
692 * The receiver's (server's) credentials are copied
693 * from the unp_peercred member of socket on which the
694 * former called listen(); unp_listen() cached that
695 * process's credentials at that time so we can use
698 KASSERT(unp2->unp_flags & UNP_HAVEPCCACHED,
699 ("unp_connect: listener without cached peercred"));
700 memcpy(&unp->unp_peercred, &unp2->unp_peercred,
701 sizeof(unp->unp_peercred));
702 unp->unp_flags |= UNP_HAVEPC;
706 error = unp_connect2(so, so2);
713 unp_connect2(struct socket *so, struct socket *so2)
715 struct unpcb *unp = so->so_pcb;
718 if (so2->so_type != so->so_type)
721 unp->unp_conn = unp2;
722 switch (so->so_type) {
725 LIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_reflink);
730 unp2->unp_conn = unp;
736 panic("unp_connect2");
742 unp_disconnect(struct unpcb *unp)
744 struct unpcb *unp2 = unp->unp_conn;
749 unp->unp_conn = NULL;
751 switch (unp->unp_socket->so_type) {
753 LIST_REMOVE(unp, unp_reflink);
754 unp->unp_socket->so_state &= ~SS_ISCONNECTED;
757 soisdisconnected(unp->unp_socket);
758 unp2->unp_conn = NULL;
759 soisdisconnected(unp2->unp_socket);
766 unp_abort(struct unpcb *unp)
774 prison_unpcb(struct thread *td, struct unpcb *unp)
780 if ((p = td->td_proc) == NULL)
782 if (!p->p_ucred->cr_prison)
784 if (p->p_fd->fd_rdir == unp->unp_rvnode)
790 unp_pcblist(SYSCTL_HANDLER_ARGS)
793 struct unpcb *unp, **unp_list;
795 struct unp_head *head;
797 head = ((intptr_t)arg1 == SOCK_DGRAM ? &unp_dhead : &unp_shead);
799 KKASSERT(curproc != NULL);
802 * The process of preparing the PCB list is too time-consuming and
803 * resource-intensive to repeat twice on every request.
805 if (req->oldptr == NULL) {
807 req->oldidx = (n + n/8) * sizeof(struct xunpcb);
811 if (req->newptr != NULL)
815 * OK, now we're committed to doing something.
820 unp_list = malloc(n * sizeof *unp_list, M_TEMP, M_WAITOK);
821 if (unp_list == NULL)
824 for (unp = LIST_FIRST(head), i = 0; unp && i < n;
825 unp = LIST_NEXT(unp, unp_link)) {
826 if (unp->unp_gencnt <= gencnt && !prison_unpcb(req->td, unp))
829 n = i; /* in case we lost some during malloc */
832 for (i = 0; i < n; i++) {
834 if (unp->unp_gencnt <= gencnt) {
836 xu.xu_len = sizeof xu;
839 * XXX - need more locking here to protect against
840 * connect/disconnect races for SMP.
843 bcopy(unp->unp_addr, &xu.xu_addr,
844 unp->unp_addr->sun_len);
845 if (unp->unp_conn && unp->unp_conn->unp_addr)
846 bcopy(unp->unp_conn->unp_addr,
848 unp->unp_conn->unp_addr->sun_len);
849 bcopy(unp, &xu.xu_unp, sizeof *unp);
850 sotoxsocket(unp->unp_socket, &xu.xu_socket);
851 error = SYSCTL_OUT(req, &xu, sizeof xu);
854 free(unp_list, M_TEMP);
858 SYSCTL_PROC(_net_local_dgram, OID_AUTO, pcblist, CTLFLAG_RD,
859 (caddr_t)(long)SOCK_DGRAM, 0, unp_pcblist, "S,xunpcb",
860 "List of active local datagram sockets");
861 SYSCTL_PROC(_net_local_stream, OID_AUTO, pcblist, CTLFLAG_RD,
862 (caddr_t)(long)SOCK_STREAM, 0, unp_pcblist, "S,xunpcb",
863 "List of active local stream sockets");
866 unp_shutdown(struct unpcb *unp)
870 if (unp->unp_socket->so_type == SOCK_STREAM && unp->unp_conn != NULL &&
871 (so = unp->unp_conn->unp_socket))
876 unp_drop(struct unpcb *unp, int errno)
878 struct socket *so = unp->unp_socket;
880 so->so_error = errno;
893 unp_externalize(struct mbuf *rights)
895 struct proc *p = curproc; /* XXX */
897 struct cmsghdr *cm = mtod(rights, struct cmsghdr *);
901 int newfds = (cm->cmsg_len - (CMSG_DATA(cm) - (u_char *)cm))
902 / sizeof (struct file *);
906 * if the new FD's will not fit, then we free them all
908 if (!fdavail(p, newfds)) {
909 rp = (struct file **)CMSG_DATA(cm);
910 for (i = 0; i < newfds; i++) {
913 * zero the pointer before calling unp_discard,
914 * since it may end up in unp_gc()..
922 * now change each pointer to an fd in the global table to
923 * an integer that is the index to the local fd table entry
924 * that we set up to point to the global one we are transferring.
925 * If sizeof (struct file *) is bigger than or equal to sizeof int,
926 * then do it in forward order. In that case, an integer will
927 * always come in the same place or before its corresponding
928 * struct file pointer.
929 * If sizeof (struct file *) is smaller than sizeof int, then
930 * do it in reverse order.
932 if (sizeof (struct file *) >= sizeof (int)) {
933 fdp = (int *)(cm + 1);
934 rp = (struct file **)CMSG_DATA(cm);
935 for (i = 0; i < newfds; i++) {
936 if (fdalloc(p, 0, &f))
937 panic("unp_externalize");
939 p->p_fd->fd_files[f].fp = fp;
945 fdp = (int *)(cm + 1) + newfds - 1;
946 rp = (struct file **)CMSG_DATA(cm) + newfds - 1;
947 for (i = 0; i < newfds; i++) {
948 if (fdalloc(p, 0, &f))
949 panic("unp_externalize");
951 p->p_fd->fd_files[f].fp = fp;
959 * Adjust length, in case sizeof(struct file *) and sizeof(int)
962 cm->cmsg_len = CMSG_LEN(newfds * sizeof(int));
963 rights->m_len = cm->cmsg_len;
970 unp_zone = zinit("unpcb", sizeof(struct unpcb), nmbclusters, 0, 0);
971 if (unp_zone == NULL)
973 LIST_INIT(&unp_dhead);
974 LIST_INIT(&unp_shead);
978 unp_internalize(struct mbuf *control, struct thread *td)
980 struct proc *p = td->td_proc;
981 struct filedesc *fdescp;
982 struct cmsghdr *cm = mtod(control, struct cmsghdr *);
986 struct cmsgcred *cmcred;
992 if ((cm->cmsg_type != SCM_RIGHTS && cm->cmsg_type != SCM_CREDS) ||
993 cm->cmsg_level != SOL_SOCKET || cm->cmsg_len != control->m_len)
997 * Fill in credential information.
999 if (cm->cmsg_type == SCM_CREDS) {
1000 cmcred = (struct cmsgcred *)(cm + 1);
1001 cmcred->cmcred_pid = p->p_pid;
1002 cmcred->cmcred_uid = p->p_ucred->cr_ruid;
1003 cmcred->cmcred_gid = p->p_ucred->cr_rgid;
1004 cmcred->cmcred_euid = p->p_ucred->cr_uid;
1005 cmcred->cmcred_ngroups = MIN(p->p_ucred->cr_ngroups,
1007 for (i = 0; i < cmcred->cmcred_ngroups; i++)
1008 cmcred->cmcred_groups[i] = p->p_ucred->cr_groups[i];
1012 oldfds = (cm->cmsg_len - sizeof (*cm)) / sizeof (int);
1014 * check that all the FDs passed in refer to legal OPEN files
1015 * If not, reject the entire operation.
1017 fdp = (int *)(cm + 1);
1018 for (i = 0; i < oldfds; i++) {
1020 if ((unsigned)fd >= fdescp->fd_nfiles ||
1021 fdescp->fd_files[fd].fp == NULL)
1023 if (fdescp->fd_files[fd].fp->f_type == DTYPE_KQUEUE)
1024 return (EOPNOTSUPP);
1027 * Now replace the integer FDs with pointers to
1028 * the associated global file table entry..
1029 * Allocate a bigger buffer as necessary. But if an cluster is not
1030 * enough, return E2BIG.
1032 newlen = CMSG_LEN(oldfds * sizeof(struct file *));
1033 if (newlen > MCLBYTES)
1035 if (newlen - control->m_len > M_TRAILINGSPACE(control)) {
1036 if (control->m_flags & M_EXT)
1038 MCLGET(control, MB_WAIT);
1039 if (!(control->m_flags & M_EXT))
1042 /* copy the data to the cluster */
1043 memcpy(mtod(control, char *), cm, cm->cmsg_len);
1044 cm = mtod(control, struct cmsghdr *);
1048 * Adjust length, in case sizeof(struct file *) and sizeof(int)
1051 control->m_len = cm->cmsg_len = newlen;
1054 * Transform the file descriptors into struct file pointers.
1055 * If sizeof (struct file *) is bigger than or equal to sizeof int,
1056 * then do it in reverse order so that the int won't get until
1058 * If sizeof (struct file *) is smaller than sizeof int, then
1059 * do it in forward order.
1061 if (sizeof (struct file *) >= sizeof (int)) {
1062 fdp = (int *)(cm + 1) + oldfds - 1;
1063 rp = (struct file **)CMSG_DATA(cm) + oldfds - 1;
1064 for (i = 0; i < oldfds; i++) {
1065 fp = fdescp->fd_files[*fdp--].fp;
1072 fdp = (int *)(cm + 1);
1073 rp = (struct file **)CMSG_DATA(cm);
1074 for (i = 0; i < oldfds; i++) {
1075 fp = fdescp->fd_files[*fdp++].fp;
1085 static int unp_defer;
1090 static boolean_t unp_gcing;
1092 struct file *fp, *nextfp;
1094 struct file **extra_ref, **fpp;
1102 * before going through all this, set all FDs to
1103 * be NOT defered and NOT externally accessible
1105 LIST_FOREACH(fp, &filehead, f_list)
1106 fp->f_flag &= ~(FMARK|FDEFER);
1108 LIST_FOREACH(fp, &filehead, f_list) {
1110 * If the file is not open, skip it
1112 if (fp->f_count == 0)
1115 * If we already marked it as 'defer' in a
1116 * previous pass, then try process it this time
1119 if (fp->f_flag & FDEFER) {
1120 fp->f_flag &= ~FDEFER;
1124 * if it's not defered, then check if it's
1125 * already marked.. if so skip it
1127 if (fp->f_flag & FMARK)
1130 * If all references are from messages
1131 * in transit, then skip it. it's not
1132 * externally accessible.
1134 if (fp->f_count == fp->f_msgcount)
1137 * If it got this far then it must be
1138 * externally accessible.
1140 fp->f_flag |= FMARK;
1143 * either it was defered, or it is externally
1144 * accessible and not already marked so.
1145 * Now check if it is possibly one of OUR sockets.
1147 if (fp->f_type != DTYPE_SOCKET ||
1148 (so = (struct socket *)fp->f_data) == NULL)
1150 if (so->so_proto->pr_domain != &localdomain ||
1151 !(so->so_proto->pr_flags & PR_RIGHTS))
1154 if (so->so_rcv.sb_flags & SB_LOCK) {
1156 * This is problematical; it's not clear
1157 * we need to wait for the sockbuf to be
1158 * unlocked (on a uniprocessor, at least),
1159 * and it's also not clear what to do
1160 * if sbwait returns an error due to receipt
1161 * of a signal. If sbwait does return
1162 * an error, we'll go into an infinite
1163 * loop. Delete all of this for now.
1165 sbwait(&so->so_rcv);
1170 * So, Ok, it's one of our sockets and it IS externally
1171 * accessible (or was defered). Now we look
1172 * to see if we hold any file descriptors in its
1173 * message buffers. Follow those links and mark them
1174 * as accessible too.
1176 unp_scan(so->so_rcv.sb_mb, unp_mark);
1178 } while (unp_defer);
1180 * We grab an extra reference to each of the file table entries
1181 * that are not otherwise accessible and then free the rights
1182 * that are stored in messages on them.
1184 * The bug in the orginal code is a little tricky, so I'll describe
1185 * what's wrong with it here.
1187 * It is incorrect to simply unp_discard each entry for f_msgcount
1188 * times -- consider the case of sockets A and B that contain
1189 * references to each other. On a last close of some other socket,
1190 * we trigger a gc since the number of outstanding rights (unp_rights)
1191 * is non-zero. If during the sweep phase the gc code un_discards,
1192 * we end up doing a (full) closef on the descriptor. A closef on A
1193 * results in the following chain. Closef calls soo_close, which
1194 * calls soclose. Soclose calls first (through the switch
1195 * uipc_usrreq) unp_detach, which re-invokes unp_gc. Unp_gc simply
1196 * returns because the previous instance had set unp_gcing, and
1197 * we return all the way back to soclose, which marks the socket
1198 * with SS_NOFDREF, and then calls sofree. Sofree calls sorflush
1199 * to free up the rights that are queued in messages on the socket A,
1200 * i.e., the reference on B. The sorflush calls via the dom_dispose
1201 * switch unp_dispose, which unp_scans with unp_discard. This second
1202 * instance of unp_discard just calls closef on B.
1204 * Well, a similar chain occurs on B, resulting in a sorflush on B,
1205 * which results in another closef on A. Unfortunately, A is already
1206 * being closed, and the descriptor has already been marked with
1207 * SS_NOFDREF, and soclose panics at this point.
1209 * Here, we first take an extra reference to each inaccessible
1210 * descriptor. Then, we call sorflush ourself, since we know
1211 * it is a Unix domain socket anyhow. After we destroy all the
1212 * rights carried in messages, we do a last closef to get rid
1213 * of our extra reference. This is the last close, and the
1214 * unp_detach etc will shut down the socket.
1216 * 91/09/19, bsy@cs.cmu.edu
1218 extra_ref = malloc(nfiles * sizeof(struct file *), M_FILE, M_WAITOK);
1219 for (nunref = 0, fp = LIST_FIRST(&filehead), fpp = extra_ref;
1220 fp != NULL; fp = nextfp) {
1221 nextfp = LIST_NEXT(fp, f_list);
1223 * If it's not open, skip it
1225 if (fp->f_count == 0)
1228 * If all refs are from msgs, and it's not marked accessible
1229 * then it must be referenced from some unreachable cycle
1230 * of (shut-down) FDs, so include it in our
1231 * list of FDs to remove
1233 if (fp->f_count == fp->f_msgcount && !(fp->f_flag & FMARK)) {
1240 * for each FD on our hit list, do the following two things
1242 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp) {
1243 struct file *tfp = *fpp;
1244 if (tfp->f_type == DTYPE_SOCKET && tfp->f_data != NULL)
1245 sorflush((struct socket *)(tfp->f_data));
1247 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp)
1249 free((caddr_t)extra_ref, M_FILE);
1254 unp_dispose(struct mbuf *m)
1257 unp_scan(m, unp_discard);
1261 unp_listen(struct unpcb *unp, struct thread *td)
1263 struct proc *p = td->td_proc;
1266 cru2x(p->p_ucred, &unp->unp_peercred);
1267 unp->unp_flags |= UNP_HAVEPCCACHED;
1272 unp_scan(struct mbuf *m0, void (*op)(struct file *))
1281 for (m = m0; m; m = m->m_next)
1282 if (m->m_type == MT_CONTROL &&
1283 m->m_len >= sizeof(*cm)) {
1284 cm = mtod(m, struct cmsghdr *);
1285 if (cm->cmsg_level != SOL_SOCKET ||
1286 cm->cmsg_type != SCM_RIGHTS)
1288 qfds = (cm->cmsg_len -
1289 (CMSG_DATA(cm) - (u_char *)cm))
1290 / sizeof (struct file *);
1291 rp = (struct file **)CMSG_DATA(cm);
1292 for (i = 0; i < qfds; i++)
1294 break; /* XXX, but saves time */
1301 unp_mark(struct file *fp)
1304 if (fp->f_flag & FMARK)
1307 fp->f_flag |= (FMARK|FDEFER);
1311 unp_discard(struct file *fp)