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[FreeBSD/FreeBSD.git] / sys / kern / uipc_usrreq.c
1 /*-
2  * Copyright (c) 1982, 1986, 1989, 1991, 1993
3  *      The Regents of the University of California.
4  * Copyright (c) 2004-2009 Robert N. M. Watson
5  * 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  * 4. 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  *      From: @(#)uipc_usrreq.c 8.3 (Berkeley) 1/4/94
32  */
33
34 /*
35  * UNIX Domain (Local) Sockets
36  *
37  * This is an implementation of UNIX (local) domain sockets.  Each socket has
38  * an associated struct unpcb (UNIX protocol control block).  Stream sockets
39  * may be connected to 0 or 1 other socket.  Datagram sockets may be
40  * connected to 0, 1, or many other sockets.  Sockets may be created and
41  * connected in pairs (socketpair(2)), or bound/connected to using the file
42  * system name space.  For most purposes, only the receive socket buffer is
43  * used, as sending on one socket delivers directly to the receive socket
44  * buffer of a second socket.
45  *
46  * The implementation is substantially complicated by the fact that
47  * "ancillary data", such as file descriptors or credentials, may be passed
48  * across UNIX domain sockets.  The potential for passing UNIX domain sockets
49  * over other UNIX domain sockets requires the implementation of a simple
50  * garbage collector to find and tear down cycles of disconnected sockets.
51  *
52  * TODO:
53  *      RDM
54  *      rethink name space problems
55  *      need a proper out-of-band
56  */
57
58 #include <sys/cdefs.h>
59 __FBSDID("$FreeBSD$");
60
61 #include "opt_ddb.h"
62
63 #include <sys/param.h>
64 #include <sys/capsicum.h>
65 #include <sys/domain.h>
66 #include <sys/fcntl.h>
67 #include <sys/malloc.h>         /* XXX must be before <sys/file.h> */
68 #include <sys/eventhandler.h>
69 #include <sys/file.h>
70 #include <sys/filedesc.h>
71 #include <sys/kernel.h>
72 #include <sys/lock.h>
73 #include <sys/mbuf.h>
74 #include <sys/mount.h>
75 #include <sys/mutex.h>
76 #include <sys/namei.h>
77 #include <sys/proc.h>
78 #include <sys/protosw.h>
79 #include <sys/queue.h>
80 #include <sys/resourcevar.h>
81 #include <sys/rwlock.h>
82 #include <sys/socket.h>
83 #include <sys/socketvar.h>
84 #include <sys/signalvar.h>
85 #include <sys/stat.h>
86 #include <sys/sx.h>
87 #include <sys/sysctl.h>
88 #include <sys/systm.h>
89 #include <sys/taskqueue.h>
90 #include <sys/un.h>
91 #include <sys/unpcb.h>
92 #include <sys/vnode.h>
93
94 #include <net/vnet.h>
95
96 #ifdef DDB
97 #include <ddb/ddb.h>
98 #endif
99
100 #include <security/mac/mac_framework.h>
101
102 #include <vm/uma.h>
103
104 MALLOC_DECLARE(M_FILECAPS);
105
106 /*
107  * Locking key:
108  * (l)  Locked using list lock
109  * (g)  Locked using linkage lock
110  */
111
112 static uma_zone_t       unp_zone;
113 static unp_gen_t        unp_gencnt;     /* (l) */
114 static u_int            unp_count;      /* (l) Count of local sockets. */
115 static ino_t            unp_ino;        /* Prototype for fake inode numbers. */
116 static int              unp_rights;     /* (g) File descriptors in flight. */
117 static struct unp_head  unp_shead;      /* (l) List of stream sockets. */
118 static struct unp_head  unp_dhead;      /* (l) List of datagram sockets. */
119 static struct unp_head  unp_sphead;     /* (l) List of seqpacket sockets. */
120
121 struct unp_defer {
122         SLIST_ENTRY(unp_defer) ud_link;
123         struct file *ud_fp;
124 };
125 static SLIST_HEAD(, unp_defer) unp_defers;
126 static int unp_defers_count;
127
128 static const struct sockaddr    sun_noname = { sizeof(sun_noname), AF_LOCAL };
129
130 /*
131  * Garbage collection of cyclic file descriptor/socket references occurs
132  * asynchronously in a taskqueue context in order to avoid recursion and
133  * reentrance in the UNIX domain socket, file descriptor, and socket layer
134  * code.  See unp_gc() for a full description.
135  */
136 static struct timeout_task unp_gc_task;
137
138 /*
139  * The close of unix domain sockets attached as SCM_RIGHTS is
140  * postponed to the taskqueue, to avoid arbitrary recursion depth.
141  * The attached sockets might have another sockets attached.
142  */
143 static struct task      unp_defer_task;
144
145 /*
146  * Both send and receive buffers are allocated PIPSIZ bytes of buffering for
147  * stream sockets, although the total for sender and receiver is actually
148  * only PIPSIZ.
149  *
150  * Datagram sockets really use the sendspace as the maximum datagram size,
151  * and don't really want to reserve the sendspace.  Their recvspace should be
152  * large enough for at least one max-size datagram plus address.
153  */
154 #ifndef PIPSIZ
155 #define PIPSIZ  8192
156 #endif
157 static u_long   unpst_sendspace = PIPSIZ;
158 static u_long   unpst_recvspace = PIPSIZ;
159 static u_long   unpdg_sendspace = 2*1024;       /* really max datagram size */
160 static u_long   unpdg_recvspace = 4*1024;
161 static u_long   unpsp_sendspace = PIPSIZ;       /* really max datagram size */
162 static u_long   unpsp_recvspace = PIPSIZ;
163
164 static SYSCTL_NODE(_net, PF_LOCAL, local, CTLFLAG_RW, 0, "Local domain");
165 static SYSCTL_NODE(_net_local, SOCK_STREAM, stream, CTLFLAG_RW, 0,
166     "SOCK_STREAM");
167 static SYSCTL_NODE(_net_local, SOCK_DGRAM, dgram, CTLFLAG_RW, 0, "SOCK_DGRAM");
168 static SYSCTL_NODE(_net_local, SOCK_SEQPACKET, seqpacket, CTLFLAG_RW, 0,
169     "SOCK_SEQPACKET");
170
171 SYSCTL_ULONG(_net_local_stream, OID_AUTO, sendspace, CTLFLAG_RW,
172            &unpst_sendspace, 0, "Default stream send space.");
173 SYSCTL_ULONG(_net_local_stream, OID_AUTO, recvspace, CTLFLAG_RW,
174            &unpst_recvspace, 0, "Default stream receive space.");
175 SYSCTL_ULONG(_net_local_dgram, OID_AUTO, maxdgram, CTLFLAG_RW,
176            &unpdg_sendspace, 0, "Default datagram send space.");
177 SYSCTL_ULONG(_net_local_dgram, OID_AUTO, recvspace, CTLFLAG_RW,
178            &unpdg_recvspace, 0, "Default datagram receive space.");
179 SYSCTL_ULONG(_net_local_seqpacket, OID_AUTO, maxseqpacket, CTLFLAG_RW,
180            &unpsp_sendspace, 0, "Default seqpacket send space.");
181 SYSCTL_ULONG(_net_local_seqpacket, OID_AUTO, recvspace, CTLFLAG_RW,
182            &unpsp_recvspace, 0, "Default seqpacket receive space.");
183 SYSCTL_INT(_net_local, OID_AUTO, inflight, CTLFLAG_RD, &unp_rights, 0,
184     "File descriptors in flight.");
185 SYSCTL_INT(_net_local, OID_AUTO, deferred, CTLFLAG_RD,
186     &unp_defers_count, 0,
187     "File descriptors deferred to taskqueue for close.");
188
189 /*
190  * Locking and synchronization:
191  *
192  * Three types of locks exit in the local domain socket implementation: a
193  * global list mutex, a global linkage rwlock, and per-unpcb mutexes.  Of the
194  * global locks, the list lock protects the socket count, global generation
195  * number, and stream/datagram global lists.  The linkage lock protects the
196  * interconnection of unpcbs, the v_socket and unp_vnode pointers, and can be
197  * held exclusively over the acquisition of multiple unpcb locks to prevent
198  * deadlock.
199  *
200  * UNIX domain sockets each have an unpcb hung off of their so_pcb pointer,
201  * allocated in pru_attach() and freed in pru_detach().  The validity of that
202  * pointer is an invariant, so no lock is required to dereference the so_pcb
203  * pointer if a valid socket reference is held by the caller.  In practice,
204  * this is always true during operations performed on a socket.  Each unpcb
205  * has a back-pointer to its socket, unp_socket, which will be stable under
206  * the same circumstances.
207  *
208  * This pointer may only be safely dereferenced as long as a valid reference
209  * to the unpcb is held.  Typically, this reference will be from the socket,
210  * or from another unpcb when the referring unpcb's lock is held (in order
211  * that the reference not be invalidated during use).  For example, to follow
212  * unp->unp_conn->unp_socket, you need unlock the lock on unp, not unp_conn,
213  * as unp_socket remains valid as long as the reference to unp_conn is valid.
214  *
215  * Fields of unpcbss are locked using a per-unpcb lock, unp_mtx.  Individual
216  * atomic reads without the lock may be performed "lockless", but more
217  * complex reads and read-modify-writes require the mutex to be held.  No
218  * lock order is defined between unpcb locks -- multiple unpcb locks may be
219  * acquired at the same time only when holding the linkage rwlock
220  * exclusively, which prevents deadlocks.
221  *
222  * Blocking with UNIX domain sockets is a tricky issue: unlike most network
223  * protocols, bind() is a non-atomic operation, and connect() requires
224  * potential sleeping in the protocol, due to potentially waiting on local or
225  * distributed file systems.  We try to separate "lookup" operations, which
226  * may sleep, and the IPC operations themselves, which typically can occur
227  * with relative atomicity as locks can be held over the entire operation.
228  *
229  * Another tricky issue is simultaneous multi-threaded or multi-process
230  * access to a single UNIX domain socket.  These are handled by the flags
231  * UNP_CONNECTING and UNP_BINDING, which prevent concurrent connecting or
232  * binding, both of which involve dropping UNIX domain socket locks in order
233  * to perform namei() and other file system operations.
234  */
235 static struct rwlock    unp_link_rwlock;
236 static struct mtx       unp_list_lock;
237 static struct mtx       unp_defers_lock;
238
239 #define UNP_LINK_LOCK_INIT()            rw_init(&unp_link_rwlock,       \
240                                             "unp_link_rwlock")
241
242 #define UNP_LINK_LOCK_ASSERT()  rw_assert(&unp_link_rwlock,     \
243                                             RA_LOCKED)
244 #define UNP_LINK_UNLOCK_ASSERT()        rw_assert(&unp_link_rwlock,     \
245                                             RA_UNLOCKED)
246
247 #define UNP_LINK_RLOCK()                rw_rlock(&unp_link_rwlock)
248 #define UNP_LINK_RUNLOCK()              rw_runlock(&unp_link_rwlock)
249 #define UNP_LINK_WLOCK()                rw_wlock(&unp_link_rwlock)
250 #define UNP_LINK_WUNLOCK()              rw_wunlock(&unp_link_rwlock)
251 #define UNP_LINK_WLOCK_ASSERT()         rw_assert(&unp_link_rwlock,     \
252                                             RA_WLOCKED)
253
254 #define UNP_LIST_LOCK_INIT()            mtx_init(&unp_list_lock,        \
255                                             "unp_list_lock", NULL, MTX_DEF)
256 #define UNP_LIST_LOCK()                 mtx_lock(&unp_list_lock)
257 #define UNP_LIST_UNLOCK()               mtx_unlock(&unp_list_lock)
258
259 #define UNP_DEFERRED_LOCK_INIT()        mtx_init(&unp_defers_lock, \
260                                             "unp_defer", NULL, MTX_DEF)
261 #define UNP_DEFERRED_LOCK()             mtx_lock(&unp_defers_lock)
262 #define UNP_DEFERRED_UNLOCK()           mtx_unlock(&unp_defers_lock)
263
264 #define UNP_PCB_LOCK_INIT(unp)          mtx_init(&(unp)->unp_mtx,       \
265                                             "unp_mtx", "unp_mtx",       \
266                                             MTX_DUPOK|MTX_DEF|MTX_RECURSE)
267 #define UNP_PCB_LOCK_DESTROY(unp)       mtx_destroy(&(unp)->unp_mtx)
268 #define UNP_PCB_LOCK(unp)               mtx_lock(&(unp)->unp_mtx)
269 #define UNP_PCB_UNLOCK(unp)             mtx_unlock(&(unp)->unp_mtx)
270 #define UNP_PCB_LOCK_ASSERT(unp)        mtx_assert(&(unp)->unp_mtx, MA_OWNED)
271
272 static int      uipc_connect2(struct socket *, struct socket *);
273 static int      uipc_ctloutput(struct socket *, struct sockopt *);
274 static int      unp_connect(struct socket *, struct sockaddr *,
275                     struct thread *);
276 static int      unp_connectat(int, struct socket *, struct sockaddr *,
277                     struct thread *);
278 static int      unp_connect2(struct socket *so, struct socket *so2, int);
279 static void     unp_disconnect(struct unpcb *unp, struct unpcb *unp2);
280 static void     unp_dispose(struct mbuf *);
281 static void     unp_shutdown(struct unpcb *);
282 static void     unp_drop(struct unpcb *, int);
283 static void     unp_gc(__unused void *, int);
284 static void     unp_scan(struct mbuf *, void (*)(struct filedescent **, int));
285 static void     unp_discard(struct file *);
286 static void     unp_freerights(struct filedescent **, int);
287 static void     unp_init(void);
288 static int      unp_internalize(struct mbuf **, struct thread *);
289 static void     unp_internalize_fp(struct file *);
290 static int      unp_externalize(struct mbuf *, struct mbuf **, int);
291 static int      unp_externalize_fp(struct file *);
292 static struct mbuf      *unp_addsockcred(struct thread *, struct mbuf *);
293 static void     unp_process_defers(void * __unused, int);
294
295 /*
296  * Definitions of protocols supported in the LOCAL domain.
297  */
298 static struct domain localdomain;
299 static struct pr_usrreqs uipc_usrreqs_dgram, uipc_usrreqs_stream;
300 static struct pr_usrreqs uipc_usrreqs_seqpacket;
301 static struct protosw localsw[] = {
302 {
303         .pr_type =              SOCK_STREAM,
304         .pr_domain =            &localdomain,
305         .pr_flags =             PR_CONNREQUIRED|PR_WANTRCVD|PR_RIGHTS,
306         .pr_ctloutput =         &uipc_ctloutput,
307         .pr_usrreqs =           &uipc_usrreqs_stream
308 },
309 {
310         .pr_type =              SOCK_DGRAM,
311         .pr_domain =            &localdomain,
312         .pr_flags =             PR_ATOMIC|PR_ADDR|PR_RIGHTS,
313         .pr_ctloutput =         &uipc_ctloutput,
314         .pr_usrreqs =           &uipc_usrreqs_dgram
315 },
316 {
317         .pr_type =              SOCK_SEQPACKET,
318         .pr_domain =            &localdomain,
319
320         /*
321          * XXXRW: For now, PR_ADDR because soreceive will bump into them
322          * due to our use of sbappendaddr.  A new sbappend variants is needed
323          * that supports both atomic record writes and control data.
324          */
325         .pr_flags =             PR_ADDR|PR_ATOMIC|PR_CONNREQUIRED|PR_WANTRCVD|
326                                     PR_RIGHTS,
327         .pr_ctloutput =         &uipc_ctloutput,
328         .pr_usrreqs =           &uipc_usrreqs_seqpacket,
329 },
330 };
331
332 static struct domain localdomain = {
333         .dom_family =           AF_LOCAL,
334         .dom_name =             "local",
335         .dom_init =             unp_init,
336         .dom_externalize =      unp_externalize,
337         .dom_dispose =          unp_dispose,
338         .dom_protosw =          localsw,
339         .dom_protoswNPROTOSW =  &localsw[sizeof(localsw)/sizeof(localsw[0])]
340 };
341 DOMAIN_SET(local);
342
343 static void
344 uipc_abort(struct socket *so)
345 {
346         struct unpcb *unp, *unp2;
347
348         unp = sotounpcb(so);
349         KASSERT(unp != NULL, ("uipc_abort: unp == NULL"));
350
351         UNP_LINK_WLOCK();
352         UNP_PCB_LOCK(unp);
353         unp2 = unp->unp_conn;
354         if (unp2 != NULL) {
355                 UNP_PCB_LOCK(unp2);
356                 unp_drop(unp2, ECONNABORTED);
357                 UNP_PCB_UNLOCK(unp2);
358         }
359         UNP_PCB_UNLOCK(unp);
360         UNP_LINK_WUNLOCK();
361 }
362
363 static int
364 uipc_accept(struct socket *so, struct sockaddr **nam)
365 {
366         struct unpcb *unp, *unp2;
367         const struct sockaddr *sa;
368
369         /*
370          * Pass back name of connected socket, if it was bound and we are
371          * still connected (our peer may have closed already!).
372          */
373         unp = sotounpcb(so);
374         KASSERT(unp != NULL, ("uipc_accept: unp == NULL"));
375
376         *nam = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK);
377         UNP_LINK_RLOCK();
378         unp2 = unp->unp_conn;
379         if (unp2 != NULL && unp2->unp_addr != NULL) {
380                 UNP_PCB_LOCK(unp2);
381                 sa = (struct sockaddr *) unp2->unp_addr;
382                 bcopy(sa, *nam, sa->sa_len);
383                 UNP_PCB_UNLOCK(unp2);
384         } else {
385                 sa = &sun_noname;
386                 bcopy(sa, *nam, sa->sa_len);
387         }
388         UNP_LINK_RUNLOCK();
389         return (0);
390 }
391
392 static int
393 uipc_attach(struct socket *so, int proto, struct thread *td)
394 {
395         u_long sendspace, recvspace;
396         struct unpcb *unp;
397         int error;
398
399         KASSERT(so->so_pcb == NULL, ("uipc_attach: so_pcb != NULL"));
400         if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
401                 switch (so->so_type) {
402                 case SOCK_STREAM:
403                         sendspace = unpst_sendspace;
404                         recvspace = unpst_recvspace;
405                         break;
406
407                 case SOCK_DGRAM:
408                         sendspace = unpdg_sendspace;
409                         recvspace = unpdg_recvspace;
410                         break;
411
412                 case SOCK_SEQPACKET:
413                         sendspace = unpsp_sendspace;
414                         recvspace = unpsp_recvspace;
415                         break;
416
417                 default:
418                         panic("uipc_attach");
419                 }
420                 error = soreserve(so, sendspace, recvspace);
421                 if (error)
422                         return (error);
423         }
424         unp = uma_zalloc(unp_zone, M_NOWAIT | M_ZERO);
425         if (unp == NULL)
426                 return (ENOBUFS);
427         LIST_INIT(&unp->unp_refs);
428         UNP_PCB_LOCK_INIT(unp);
429         unp->unp_socket = so;
430         so->so_pcb = unp;
431         unp->unp_refcount = 1;
432
433         UNP_LIST_LOCK();
434         unp->unp_gencnt = ++unp_gencnt;
435         unp_count++;
436         switch (so->so_type) {
437         case SOCK_STREAM:
438                 LIST_INSERT_HEAD(&unp_shead, unp, unp_link);
439                 break;
440
441         case SOCK_DGRAM:
442                 LIST_INSERT_HEAD(&unp_dhead, unp, unp_link);
443                 break;
444
445         case SOCK_SEQPACKET:
446                 LIST_INSERT_HEAD(&unp_sphead, unp, unp_link);
447                 break;
448
449         default:
450                 panic("uipc_attach");
451         }
452         UNP_LIST_UNLOCK();
453
454         return (0);
455 }
456
457 static int
458 uipc_bindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
459 {
460         struct sockaddr_un *soun = (struct sockaddr_un *)nam;
461         struct vattr vattr;
462         int error, namelen;
463         struct nameidata nd;
464         struct unpcb *unp;
465         struct vnode *vp;
466         struct mount *mp;
467         cap_rights_t rights;
468         char *buf;
469
470         if (nam->sa_family != AF_UNIX)
471                 return (EAFNOSUPPORT);
472
473         unp = sotounpcb(so);
474         KASSERT(unp != NULL, ("uipc_bind: unp == NULL"));
475
476         if (soun->sun_len > sizeof(struct sockaddr_un))
477                 return (EINVAL);
478         namelen = soun->sun_len - offsetof(struct sockaddr_un, sun_path);
479         if (namelen <= 0)
480                 return (EINVAL);
481
482         /*
483          * We don't allow simultaneous bind() calls on a single UNIX domain
484          * socket, so flag in-progress operations, and return an error if an
485          * operation is already in progress.
486          *
487          * Historically, we have not allowed a socket to be rebound, so this
488          * also returns an error.  Not allowing re-binding simplifies the
489          * implementation and avoids a great many possible failure modes.
490          */
491         UNP_PCB_LOCK(unp);
492         if (unp->unp_vnode != NULL) {
493                 UNP_PCB_UNLOCK(unp);
494                 return (EINVAL);
495         }
496         if (unp->unp_flags & UNP_BINDING) {
497                 UNP_PCB_UNLOCK(unp);
498                 return (EALREADY);
499         }
500         unp->unp_flags |= UNP_BINDING;
501         UNP_PCB_UNLOCK(unp);
502
503         buf = malloc(namelen + 1, M_TEMP, M_WAITOK);
504         bcopy(soun->sun_path, buf, namelen);
505         buf[namelen] = 0;
506
507 restart:
508         NDINIT_ATRIGHTS(&nd, CREATE, NOFOLLOW | LOCKPARENT | SAVENAME | NOCACHE,
509             UIO_SYSSPACE, buf, fd, cap_rights_init(&rights, CAP_BINDAT), td);
510 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */
511         error = namei(&nd);
512         if (error)
513                 goto error;
514         vp = nd.ni_vp;
515         if (vp != NULL || vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
516                 NDFREE(&nd, NDF_ONLY_PNBUF);
517                 if (nd.ni_dvp == vp)
518                         vrele(nd.ni_dvp);
519                 else
520                         vput(nd.ni_dvp);
521                 if (vp != NULL) {
522                         vrele(vp);
523                         error = EADDRINUSE;
524                         goto error;
525                 }
526                 error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH);
527                 if (error)
528                         goto error;
529                 goto restart;
530         }
531         VATTR_NULL(&vattr);
532         vattr.va_type = VSOCK;
533         vattr.va_mode = (ACCESSPERMS & ~td->td_proc->p_fd->fd_cmask);
534 #ifdef MAC
535         error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
536             &vattr);
537 #endif
538         if (error == 0)
539                 error = VOP_CREATE(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
540         NDFREE(&nd, NDF_ONLY_PNBUF);
541         vput(nd.ni_dvp);
542         if (error) {
543                 vn_finished_write(mp);
544                 goto error;
545         }
546         vp = nd.ni_vp;
547         ASSERT_VOP_ELOCKED(vp, "uipc_bind");
548         soun = (struct sockaddr_un *)sodupsockaddr(nam, M_WAITOK);
549
550         UNP_LINK_WLOCK();
551         UNP_PCB_LOCK(unp);
552         VOP_UNP_BIND(vp, unp->unp_socket);
553         unp->unp_vnode = vp;
554         unp->unp_addr = soun;
555         unp->unp_flags &= ~UNP_BINDING;
556         UNP_PCB_UNLOCK(unp);
557         UNP_LINK_WUNLOCK();
558         VOP_UNLOCK(vp, 0);
559         vn_finished_write(mp);
560         free(buf, M_TEMP);
561         return (0);
562
563 error:
564         UNP_PCB_LOCK(unp);
565         unp->unp_flags &= ~UNP_BINDING;
566         UNP_PCB_UNLOCK(unp);
567         free(buf, M_TEMP);
568         return (error);
569 }
570
571 static int
572 uipc_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
573 {
574
575         return (uipc_bindat(AT_FDCWD, so, nam, td));
576 }
577
578 static int
579 uipc_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
580 {
581         int error;
582
583         KASSERT(td == curthread, ("uipc_connect: td != curthread"));
584         UNP_LINK_WLOCK();
585         error = unp_connect(so, nam, td);
586         UNP_LINK_WUNLOCK();
587         return (error);
588 }
589
590 static int
591 uipc_connectat(int fd, struct socket *so, struct sockaddr *nam,
592     struct thread *td)
593 {
594         int error;
595
596         KASSERT(td == curthread, ("uipc_connectat: td != curthread"));
597         UNP_LINK_WLOCK();
598         error = unp_connectat(fd, so, nam, td);
599         UNP_LINK_WUNLOCK();
600         return (error);
601 }
602
603 static void
604 uipc_close(struct socket *so)
605 {
606         struct unpcb *unp, *unp2;
607
608         unp = sotounpcb(so);
609         KASSERT(unp != NULL, ("uipc_close: unp == NULL"));
610
611         UNP_LINK_WLOCK();
612         UNP_PCB_LOCK(unp);
613         unp2 = unp->unp_conn;
614         if (unp2 != NULL) {
615                 UNP_PCB_LOCK(unp2);
616                 unp_disconnect(unp, unp2);
617                 UNP_PCB_UNLOCK(unp2);
618         }
619         UNP_PCB_UNLOCK(unp);
620         UNP_LINK_WUNLOCK();
621 }
622
623 static int
624 uipc_connect2(struct socket *so1, struct socket *so2)
625 {
626         struct unpcb *unp, *unp2;
627         int error;
628
629         UNP_LINK_WLOCK();
630         unp = so1->so_pcb;
631         KASSERT(unp != NULL, ("uipc_connect2: unp == NULL"));
632         UNP_PCB_LOCK(unp);
633         unp2 = so2->so_pcb;
634         KASSERT(unp2 != NULL, ("uipc_connect2: unp2 == NULL"));
635         UNP_PCB_LOCK(unp2);
636         error = unp_connect2(so1, so2, PRU_CONNECT2);
637         UNP_PCB_UNLOCK(unp2);
638         UNP_PCB_UNLOCK(unp);
639         UNP_LINK_WUNLOCK();
640         return (error);
641 }
642
643 static void
644 uipc_detach(struct socket *so)
645 {
646         struct unpcb *unp, *unp2;
647         struct sockaddr_un *saved_unp_addr;
648         struct vnode *vp;
649         int freeunp, local_unp_rights;
650
651         unp = sotounpcb(so);
652         KASSERT(unp != NULL, ("uipc_detach: unp == NULL"));
653
654         UNP_LINK_WLOCK();
655         UNP_LIST_LOCK();
656         UNP_PCB_LOCK(unp);
657         LIST_REMOVE(unp, unp_link);
658         unp->unp_gencnt = ++unp_gencnt;
659         --unp_count;
660         UNP_LIST_UNLOCK();
661
662         /*
663          * XXXRW: Should assert vp->v_socket == so.
664          */
665         if ((vp = unp->unp_vnode) != NULL) {
666                 VOP_UNP_DETACH(vp);
667                 unp->unp_vnode = NULL;
668         }
669         unp2 = unp->unp_conn;
670         if (unp2 != NULL) {
671                 UNP_PCB_LOCK(unp2);
672                 unp_disconnect(unp, unp2);
673                 UNP_PCB_UNLOCK(unp2);
674         }
675
676         /*
677          * We hold the linkage lock exclusively, so it's OK to acquire
678          * multiple pcb locks at a time.
679          */
680         while (!LIST_EMPTY(&unp->unp_refs)) {
681                 struct unpcb *ref = LIST_FIRST(&unp->unp_refs);
682
683                 UNP_PCB_LOCK(ref);
684                 unp_drop(ref, ECONNRESET);
685                 UNP_PCB_UNLOCK(ref);
686         }
687         local_unp_rights = unp_rights;
688         UNP_LINK_WUNLOCK();
689         unp->unp_socket->so_pcb = NULL;
690         saved_unp_addr = unp->unp_addr;
691         unp->unp_addr = NULL;
692         unp->unp_refcount--;
693         freeunp = (unp->unp_refcount == 0);
694         if (saved_unp_addr != NULL)
695                 free(saved_unp_addr, M_SONAME);
696         if (freeunp) {
697                 UNP_PCB_LOCK_DESTROY(unp);
698                 uma_zfree(unp_zone, unp);
699         } else
700                 UNP_PCB_UNLOCK(unp);
701         if (vp)
702                 vrele(vp);
703         if (local_unp_rights)
704                 taskqueue_enqueue_timeout(taskqueue_thread, &unp_gc_task, -1);
705 }
706
707 static int
708 uipc_disconnect(struct socket *so)
709 {
710         struct unpcb *unp, *unp2;
711
712         unp = sotounpcb(so);
713         KASSERT(unp != NULL, ("uipc_disconnect: unp == NULL"));
714
715         UNP_LINK_WLOCK();
716         UNP_PCB_LOCK(unp);
717         unp2 = unp->unp_conn;
718         if (unp2 != NULL) {
719                 UNP_PCB_LOCK(unp2);
720                 unp_disconnect(unp, unp2);
721                 UNP_PCB_UNLOCK(unp2);
722         }
723         UNP_PCB_UNLOCK(unp);
724         UNP_LINK_WUNLOCK();
725         return (0);
726 }
727
728 static int
729 uipc_listen(struct socket *so, int backlog, struct thread *td)
730 {
731         struct unpcb *unp;
732         int error;
733
734         unp = sotounpcb(so);
735         KASSERT(unp != NULL, ("uipc_listen: unp == NULL"));
736
737         UNP_PCB_LOCK(unp);
738         if (unp->unp_vnode == NULL) {
739                 UNP_PCB_UNLOCK(unp);
740                 return (EINVAL);
741         }
742
743         SOCK_LOCK(so);
744         error = solisten_proto_check(so);
745         if (error == 0) {
746                 cru2x(td->td_ucred, &unp->unp_peercred);
747                 unp->unp_flags |= UNP_HAVEPCCACHED;
748                 solisten_proto(so, backlog);
749         }
750         SOCK_UNLOCK(so);
751         UNP_PCB_UNLOCK(unp);
752         return (error);
753 }
754
755 static int
756 uipc_peeraddr(struct socket *so, struct sockaddr **nam)
757 {
758         struct unpcb *unp, *unp2;
759         const struct sockaddr *sa;
760
761         unp = sotounpcb(so);
762         KASSERT(unp != NULL, ("uipc_peeraddr: unp == NULL"));
763
764         *nam = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK);
765         UNP_LINK_RLOCK();
766         /*
767          * XXX: It seems that this test always fails even when connection is
768          * established.  So, this else clause is added as workaround to
769          * return PF_LOCAL sockaddr.
770          */
771         unp2 = unp->unp_conn;
772         if (unp2 != NULL) {
773                 UNP_PCB_LOCK(unp2);
774                 if (unp2->unp_addr != NULL)
775                         sa = (struct sockaddr *) unp2->unp_addr;
776                 else
777                         sa = &sun_noname;
778                 bcopy(sa, *nam, sa->sa_len);
779                 UNP_PCB_UNLOCK(unp2);
780         } else {
781                 sa = &sun_noname;
782                 bcopy(sa, *nam, sa->sa_len);
783         }
784         UNP_LINK_RUNLOCK();
785         return (0);
786 }
787
788 static int
789 uipc_rcvd(struct socket *so, int flags)
790 {
791         struct unpcb *unp, *unp2;
792         struct socket *so2;
793         u_int mbcnt, sbcc;
794
795         unp = sotounpcb(so);
796         KASSERT(unp != NULL, ("%s: unp == NULL", __func__));
797         KASSERT(so->so_type == SOCK_STREAM || so->so_type == SOCK_SEQPACKET,
798             ("%s: socktype %d", __func__, so->so_type));
799
800         /*
801          * Adjust backpressure on sender and wakeup any waiting to write.
802          *
803          * The unp lock is acquired to maintain the validity of the unp_conn
804          * pointer; no lock on unp2 is required as unp2->unp_socket will be
805          * static as long as we don't permit unp2 to disconnect from unp,
806          * which is prevented by the lock on unp.  We cache values from
807          * so_rcv to avoid holding the so_rcv lock over the entire
808          * transaction on the remote so_snd.
809          */
810         SOCKBUF_LOCK(&so->so_rcv);
811         mbcnt = so->so_rcv.sb_mbcnt;
812         sbcc = sbavail(&so->so_rcv);
813         SOCKBUF_UNLOCK(&so->so_rcv);
814         /*
815          * There is a benign race condition at this point.  If we're planning to
816          * clear SB_STOP, but uipc_send is called on the connected socket at
817          * this instant, it might add data to the sockbuf and set SB_STOP.  Then
818          * we would erroneously clear SB_STOP below, even though the sockbuf is
819          * full.  The race is benign because the only ill effect is to allow the
820          * sockbuf to exceed its size limit, and the size limits are not
821          * strictly guaranteed anyway.
822          */
823         UNP_PCB_LOCK(unp);
824         unp2 = unp->unp_conn;
825         if (unp2 == NULL) {
826                 UNP_PCB_UNLOCK(unp);
827                 return (0);
828         }
829         so2 = unp2->unp_socket;
830         SOCKBUF_LOCK(&so2->so_snd);
831         if (sbcc < so2->so_snd.sb_hiwat && mbcnt < so2->so_snd.sb_mbmax)
832                 so2->so_snd.sb_flags &= ~SB_STOP;
833         sowwakeup_locked(so2);
834         UNP_PCB_UNLOCK(unp);
835         return (0);
836 }
837
838 static int
839 uipc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
840     struct mbuf *control, struct thread *td)
841 {
842         struct unpcb *unp, *unp2;
843         struct socket *so2;
844         u_int mbcnt, sbcc;
845         int error = 0;
846
847         unp = sotounpcb(so);
848         KASSERT(unp != NULL, ("%s: unp == NULL", __func__));
849         KASSERT(so->so_type == SOCK_STREAM || so->so_type == SOCK_DGRAM ||
850             so->so_type == SOCK_SEQPACKET,
851             ("%s: socktype %d", __func__, so->so_type));
852
853         if (flags & PRUS_OOB) {
854                 error = EOPNOTSUPP;
855                 goto release;
856         }
857         if (control != NULL && (error = unp_internalize(&control, td)))
858                 goto release;
859         if ((nam != NULL) || (flags & PRUS_EOF))
860                 UNP_LINK_WLOCK();
861         else
862                 UNP_LINK_RLOCK();
863         switch (so->so_type) {
864         case SOCK_DGRAM:
865         {
866                 const struct sockaddr *from;
867
868                 unp2 = unp->unp_conn;
869                 if (nam != NULL) {
870                         UNP_LINK_WLOCK_ASSERT();
871                         if (unp2 != NULL) {
872                                 error = EISCONN;
873                                 break;
874                         }
875                         error = unp_connect(so, nam, td);
876                         if (error)
877                                 break;
878                         unp2 = unp->unp_conn;
879                 }
880
881                 /*
882                  * Because connect() and send() are non-atomic in a sendto()
883                  * with a target address, it's possible that the socket will
884                  * have disconnected before the send() can run.  In that case
885                  * return the slightly counter-intuitive but otherwise
886                  * correct error that the socket is not connected.
887                  */
888                 if (unp2 == NULL) {
889                         error = ENOTCONN;
890                         break;
891                 }
892                 /* Lockless read. */
893                 if (unp2->unp_flags & UNP_WANTCRED)
894                         control = unp_addsockcred(td, control);
895                 UNP_PCB_LOCK(unp);
896                 if (unp->unp_addr != NULL)
897                         from = (struct sockaddr *)unp->unp_addr;
898                 else
899                         from = &sun_noname;
900                 so2 = unp2->unp_socket;
901                 SOCKBUF_LOCK(&so2->so_rcv);
902                 if (sbappendaddr_locked(&so2->so_rcv, from, m,
903                     control)) {
904                         sorwakeup_locked(so2);
905                         m = NULL;
906                         control = NULL;
907                 } else {
908                         SOCKBUF_UNLOCK(&so2->so_rcv);
909                         error = ENOBUFS;
910                 }
911                 if (nam != NULL) {
912                         UNP_LINK_WLOCK_ASSERT();
913                         UNP_PCB_LOCK(unp2);
914                         unp_disconnect(unp, unp2);
915                         UNP_PCB_UNLOCK(unp2);
916                 }
917                 UNP_PCB_UNLOCK(unp);
918                 break;
919         }
920
921         case SOCK_SEQPACKET:
922         case SOCK_STREAM:
923                 if ((so->so_state & SS_ISCONNECTED) == 0) {
924                         if (nam != NULL) {
925                                 UNP_LINK_WLOCK_ASSERT();
926                                 error = unp_connect(so, nam, td);
927                                 if (error)
928                                         break;  /* XXX */
929                         } else {
930                                 error = ENOTCONN;
931                                 break;
932                         }
933                 }
934
935                 /* Lockless read. */
936                 if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
937                         error = EPIPE;
938                         break;
939                 }
940
941                 /*
942                  * Because connect() and send() are non-atomic in a sendto()
943                  * with a target address, it's possible that the socket will
944                  * have disconnected before the send() can run.  In that case
945                  * return the slightly counter-intuitive but otherwise
946                  * correct error that the socket is not connected.
947                  *
948                  * Locking here must be done carefully: the linkage lock
949                  * prevents interconnections between unpcbs from changing, so
950                  * we can traverse from unp to unp2 without acquiring unp's
951                  * lock.  Socket buffer locks follow unpcb locks, so we can
952                  * acquire both remote and lock socket buffer locks.
953                  */
954                 unp2 = unp->unp_conn;
955                 if (unp2 == NULL) {
956                         error = ENOTCONN;
957                         break;
958                 }
959                 so2 = unp2->unp_socket;
960                 UNP_PCB_LOCK(unp2);
961                 SOCKBUF_LOCK(&so2->so_rcv);
962                 if (unp2->unp_flags & UNP_WANTCRED) {
963                         /*
964                          * Credentials are passed only once on SOCK_STREAM
965                          * and SOCK_SEQPACKET.
966                          */
967                         unp2->unp_flags &= ~UNP_WANTCRED;
968                         control = unp_addsockcred(td, control);
969                 }
970                 /*
971                  * Send to paired receive port, and then reduce send buffer
972                  * hiwater marks to maintain backpressure.  Wake up readers.
973                  */
974                 switch (so->so_type) {
975                 case SOCK_STREAM:
976                         if (control != NULL) {
977                                 if (sbappendcontrol_locked(&so2->so_rcv, m,
978                                     control))
979                                         control = NULL;
980                         } else
981                                 sbappend_locked(&so2->so_rcv, m);
982                         break;
983
984                 case SOCK_SEQPACKET: {
985                         const struct sockaddr *from;
986
987                         from = &sun_noname;
988                         /*
989                          * Don't check for space available in so2->so_rcv.
990                          * Unix domain sockets only check for space in the
991                          * sending sockbuf, and that check is performed one
992                          * level up the stack.
993                          */
994                         if (sbappendaddr_nospacecheck_locked(&so2->so_rcv,
995                                 from, m, control))
996                                 control = NULL;
997                         break;
998                         }
999                 }
1000
1001                 mbcnt = so2->so_rcv.sb_mbcnt;
1002                 sbcc = sbavail(&so2->so_rcv);
1003                 if (sbcc)
1004                         sorwakeup_locked(so2);
1005                 else
1006                         SOCKBUF_UNLOCK(&so2->so_rcv);
1007
1008                 /*
1009                  * The PCB lock on unp2 protects the SB_STOP flag.  Without it,
1010                  * it would be possible for uipc_rcvd to be called at this
1011                  * point, drain the receiving sockbuf, clear SB_STOP, and then
1012                  * we would set SB_STOP below.  That could lead to an empty
1013                  * sockbuf having SB_STOP set
1014                  */
1015                 SOCKBUF_LOCK(&so->so_snd);
1016                 if (sbcc >= so->so_snd.sb_hiwat || mbcnt >= so->so_snd.sb_mbmax)
1017                         so->so_snd.sb_flags |= SB_STOP;
1018                 SOCKBUF_UNLOCK(&so->so_snd);
1019                 UNP_PCB_UNLOCK(unp2);
1020                 m = NULL;
1021                 break;
1022         }
1023
1024         /*
1025          * PRUS_EOF is equivalent to pru_send followed by pru_shutdown.
1026          */
1027         if (flags & PRUS_EOF) {
1028                 UNP_PCB_LOCK(unp);
1029                 socantsendmore(so);
1030                 unp_shutdown(unp);
1031                 UNP_PCB_UNLOCK(unp);
1032         }
1033
1034         if ((nam != NULL) || (flags & PRUS_EOF))
1035                 UNP_LINK_WUNLOCK();
1036         else
1037                 UNP_LINK_RUNLOCK();
1038
1039         if (control != NULL && error != 0)
1040                 unp_dispose(control);
1041
1042 release:
1043         if (control != NULL)
1044                 m_freem(control);
1045         if (m != NULL)
1046                 m_freem(m);
1047         return (error);
1048 }
1049
1050 static int
1051 uipc_ready(struct socket *so, struct mbuf *m, int count)
1052 {
1053         struct unpcb *unp, *unp2;
1054         struct socket *so2;
1055         int error;
1056
1057         unp = sotounpcb(so);
1058
1059         UNP_LINK_RLOCK();
1060         unp2 = unp->unp_conn;
1061         UNP_PCB_LOCK(unp2);
1062         so2 = unp2->unp_socket;
1063
1064         SOCKBUF_LOCK(&so2->so_rcv);
1065         if ((error = sbready(&so2->so_rcv, m, count)) == 0)
1066                 sorwakeup_locked(so2);
1067         else
1068                 SOCKBUF_UNLOCK(&so2->so_rcv);
1069
1070         UNP_PCB_UNLOCK(unp2);
1071         UNP_LINK_RUNLOCK();
1072
1073         return (error);
1074 }
1075
1076 static int
1077 uipc_sense(struct socket *so, struct stat *sb)
1078 {
1079         struct unpcb *unp;
1080
1081         unp = sotounpcb(so);
1082         KASSERT(unp != NULL, ("uipc_sense: unp == NULL"));
1083
1084         sb->st_blksize = so->so_snd.sb_hiwat;
1085         UNP_PCB_LOCK(unp);
1086         sb->st_dev = NODEV;
1087         if (unp->unp_ino == 0)
1088                 unp->unp_ino = (++unp_ino == 0) ? ++unp_ino : unp_ino;
1089         sb->st_ino = unp->unp_ino;
1090         UNP_PCB_UNLOCK(unp);
1091         return (0);
1092 }
1093
1094 static int
1095 uipc_shutdown(struct socket *so)
1096 {
1097         struct unpcb *unp;
1098
1099         unp = sotounpcb(so);
1100         KASSERT(unp != NULL, ("uipc_shutdown: unp == NULL"));
1101
1102         UNP_LINK_WLOCK();
1103         UNP_PCB_LOCK(unp);
1104         socantsendmore(so);
1105         unp_shutdown(unp);
1106         UNP_PCB_UNLOCK(unp);
1107         UNP_LINK_WUNLOCK();
1108         return (0);
1109 }
1110
1111 static int
1112 uipc_sockaddr(struct socket *so, struct sockaddr **nam)
1113 {
1114         struct unpcb *unp;
1115         const struct sockaddr *sa;
1116
1117         unp = sotounpcb(so);
1118         KASSERT(unp != NULL, ("uipc_sockaddr: unp == NULL"));
1119
1120         *nam = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK);
1121         UNP_PCB_LOCK(unp);
1122         if (unp->unp_addr != NULL)
1123                 sa = (struct sockaddr *) unp->unp_addr;
1124         else
1125                 sa = &sun_noname;
1126         bcopy(sa, *nam, sa->sa_len);
1127         UNP_PCB_UNLOCK(unp);
1128         return (0);
1129 }
1130
1131 static struct pr_usrreqs uipc_usrreqs_dgram = {
1132         .pru_abort =            uipc_abort,
1133         .pru_accept =           uipc_accept,
1134         .pru_attach =           uipc_attach,
1135         .pru_bind =             uipc_bind,
1136         .pru_bindat =           uipc_bindat,
1137         .pru_connect =          uipc_connect,
1138         .pru_connectat =        uipc_connectat,
1139         .pru_connect2 =         uipc_connect2,
1140         .pru_detach =           uipc_detach,
1141         .pru_disconnect =       uipc_disconnect,
1142         .pru_listen =           uipc_listen,
1143         .pru_peeraddr =         uipc_peeraddr,
1144         .pru_rcvd =             uipc_rcvd,
1145         .pru_send =             uipc_send,
1146         .pru_sense =            uipc_sense,
1147         .pru_shutdown =         uipc_shutdown,
1148         .pru_sockaddr =         uipc_sockaddr,
1149         .pru_soreceive =        soreceive_dgram,
1150         .pru_close =            uipc_close,
1151 };
1152
1153 static struct pr_usrreqs uipc_usrreqs_seqpacket = {
1154         .pru_abort =            uipc_abort,
1155         .pru_accept =           uipc_accept,
1156         .pru_attach =           uipc_attach,
1157         .pru_bind =             uipc_bind,
1158         .pru_bindat =           uipc_bindat,
1159         .pru_connect =          uipc_connect,
1160         .pru_connectat =        uipc_connectat,
1161         .pru_connect2 =         uipc_connect2,
1162         .pru_detach =           uipc_detach,
1163         .pru_disconnect =       uipc_disconnect,
1164         .pru_listen =           uipc_listen,
1165         .pru_peeraddr =         uipc_peeraddr,
1166         .pru_rcvd =             uipc_rcvd,
1167         .pru_send =             uipc_send,
1168         .pru_sense =            uipc_sense,
1169         .pru_shutdown =         uipc_shutdown,
1170         .pru_sockaddr =         uipc_sockaddr,
1171         .pru_soreceive =        soreceive_generic,      /* XXX: or...? */
1172         .pru_close =            uipc_close,
1173 };
1174
1175 static struct pr_usrreqs uipc_usrreqs_stream = {
1176         .pru_abort =            uipc_abort,
1177         .pru_accept =           uipc_accept,
1178         .pru_attach =           uipc_attach,
1179         .pru_bind =             uipc_bind,
1180         .pru_bindat =           uipc_bindat,
1181         .pru_connect =          uipc_connect,
1182         .pru_connectat =        uipc_connectat,
1183         .pru_connect2 =         uipc_connect2,
1184         .pru_detach =           uipc_detach,
1185         .pru_disconnect =       uipc_disconnect,
1186         .pru_listen =           uipc_listen,
1187         .pru_peeraddr =         uipc_peeraddr,
1188         .pru_rcvd =             uipc_rcvd,
1189         .pru_send =             uipc_send,
1190         .pru_ready =            uipc_ready,
1191         .pru_sense =            uipc_sense,
1192         .pru_shutdown =         uipc_shutdown,
1193         .pru_sockaddr =         uipc_sockaddr,
1194         .pru_soreceive =        soreceive_generic,
1195         .pru_close =            uipc_close,
1196 };
1197
1198 static int
1199 uipc_ctloutput(struct socket *so, struct sockopt *sopt)
1200 {
1201         struct unpcb *unp;
1202         struct xucred xu;
1203         int error, optval;
1204
1205         if (sopt->sopt_level != 0)
1206                 return (EINVAL);
1207
1208         unp = sotounpcb(so);
1209         KASSERT(unp != NULL, ("uipc_ctloutput: unp == NULL"));
1210         error = 0;
1211         switch (sopt->sopt_dir) {
1212         case SOPT_GET:
1213                 switch (sopt->sopt_name) {
1214                 case LOCAL_PEERCRED:
1215                         UNP_PCB_LOCK(unp);
1216                         if (unp->unp_flags & UNP_HAVEPC)
1217                                 xu = unp->unp_peercred;
1218                         else {
1219                                 if (so->so_type == SOCK_STREAM)
1220                                         error = ENOTCONN;
1221                                 else
1222                                         error = EINVAL;
1223                         }
1224                         UNP_PCB_UNLOCK(unp);
1225                         if (error == 0)
1226                                 error = sooptcopyout(sopt, &xu, sizeof(xu));
1227                         break;
1228
1229                 case LOCAL_CREDS:
1230                         /* Unlocked read. */
1231                         optval = unp->unp_flags & UNP_WANTCRED ? 1 : 0;
1232                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1233                         break;
1234
1235                 case LOCAL_CONNWAIT:
1236                         /* Unlocked read. */
1237                         optval = unp->unp_flags & UNP_CONNWAIT ? 1 : 0;
1238                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1239                         break;
1240
1241                 default:
1242                         error = EOPNOTSUPP;
1243                         break;
1244                 }
1245                 break;
1246
1247         case SOPT_SET:
1248                 switch (sopt->sopt_name) {
1249                 case LOCAL_CREDS:
1250                 case LOCAL_CONNWAIT:
1251                         error = sooptcopyin(sopt, &optval, sizeof(optval),
1252                                             sizeof(optval));
1253                         if (error)
1254                                 break;
1255
1256 #define OPTSET(bit) do {                                                \
1257         UNP_PCB_LOCK(unp);                                              \
1258         if (optval)                                                     \
1259                 unp->unp_flags |= bit;                                  \
1260         else                                                            \
1261                 unp->unp_flags &= ~bit;                                 \
1262         UNP_PCB_UNLOCK(unp);                                            \
1263 } while (0)
1264
1265                         switch (sopt->sopt_name) {
1266                         case LOCAL_CREDS:
1267                                 OPTSET(UNP_WANTCRED);
1268                                 break;
1269
1270                         case LOCAL_CONNWAIT:
1271                                 OPTSET(UNP_CONNWAIT);
1272                                 break;
1273
1274                         default:
1275                                 break;
1276                         }
1277                         break;
1278 #undef  OPTSET
1279                 default:
1280                         error = ENOPROTOOPT;
1281                         break;
1282                 }
1283                 break;
1284
1285         default:
1286                 error = EOPNOTSUPP;
1287                 break;
1288         }
1289         return (error);
1290 }
1291
1292 static int
1293 unp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1294 {
1295
1296         return (unp_connectat(AT_FDCWD, so, nam, td));
1297 }
1298
1299 static int
1300 unp_connectat(int fd, struct socket *so, struct sockaddr *nam,
1301     struct thread *td)
1302 {
1303         struct sockaddr_un *soun = (struct sockaddr_un *)nam;
1304         struct vnode *vp;
1305         struct socket *so2, *so3;
1306         struct unpcb *unp, *unp2, *unp3;
1307         struct nameidata nd;
1308         char buf[SOCK_MAXADDRLEN];
1309         struct sockaddr *sa;
1310         cap_rights_t rights;
1311         int error, len;
1312
1313         if (nam->sa_family != AF_UNIX)
1314                 return (EAFNOSUPPORT);
1315
1316         UNP_LINK_WLOCK_ASSERT();
1317
1318         unp = sotounpcb(so);
1319         KASSERT(unp != NULL, ("unp_connect: unp == NULL"));
1320
1321         if (nam->sa_len > sizeof(struct sockaddr_un))
1322                 return (EINVAL);
1323         len = nam->sa_len - offsetof(struct sockaddr_un, sun_path);
1324         if (len <= 0)
1325                 return (EINVAL);
1326         bcopy(soun->sun_path, buf, len);
1327         buf[len] = 0;
1328
1329         UNP_PCB_LOCK(unp);
1330         if (unp->unp_flags & UNP_CONNECTING) {
1331                 UNP_PCB_UNLOCK(unp);
1332                 return (EALREADY);
1333         }
1334         UNP_LINK_WUNLOCK();
1335         unp->unp_flags |= UNP_CONNECTING;
1336         UNP_PCB_UNLOCK(unp);
1337
1338         sa = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK);
1339         NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF,
1340             UIO_SYSSPACE, buf, fd, cap_rights_init(&rights, CAP_CONNECTAT), td);
1341         error = namei(&nd);
1342         if (error)
1343                 vp = NULL;
1344         else
1345                 vp = nd.ni_vp;
1346         ASSERT_VOP_LOCKED(vp, "unp_connect");
1347         NDFREE(&nd, NDF_ONLY_PNBUF);
1348         if (error)
1349                 goto bad;
1350
1351         if (vp->v_type != VSOCK) {
1352                 error = ENOTSOCK;
1353                 goto bad;
1354         }
1355 #ifdef MAC
1356         error = mac_vnode_check_open(td->td_ucred, vp, VWRITE | VREAD);
1357         if (error)
1358                 goto bad;
1359 #endif
1360         error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td);
1361         if (error)
1362                 goto bad;
1363
1364         unp = sotounpcb(so);
1365         KASSERT(unp != NULL, ("unp_connect: unp == NULL"));
1366
1367         /*
1368          * Lock linkage lock for two reasons: make sure v_socket is stable,
1369          * and to protect simultaneous locking of multiple pcbs.
1370          */
1371         UNP_LINK_WLOCK();
1372         VOP_UNP_CONNECT(vp, &so2);
1373         if (so2 == NULL) {
1374                 error = ECONNREFUSED;
1375                 goto bad2;
1376         }
1377         if (so->so_type != so2->so_type) {
1378                 error = EPROTOTYPE;
1379                 goto bad2;
1380         }
1381         if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
1382                 if (so2->so_options & SO_ACCEPTCONN) {
1383                         CURVNET_SET(so2->so_vnet);
1384                         so3 = sonewconn(so2, 0);
1385                         CURVNET_RESTORE();
1386                 } else
1387                         so3 = NULL;
1388                 if (so3 == NULL) {
1389                         error = ECONNREFUSED;
1390                         goto bad2;
1391                 }
1392                 unp = sotounpcb(so);
1393                 unp2 = sotounpcb(so2);
1394                 unp3 = sotounpcb(so3);
1395                 UNP_PCB_LOCK(unp);
1396                 UNP_PCB_LOCK(unp2);
1397                 UNP_PCB_LOCK(unp3);
1398                 if (unp2->unp_addr != NULL) {
1399                         bcopy(unp2->unp_addr, sa, unp2->unp_addr->sun_len);
1400                         unp3->unp_addr = (struct sockaddr_un *) sa;
1401                         sa = NULL;
1402                 }
1403
1404                 /*
1405                  * The connector's (client's) credentials are copied from its
1406                  * process structure at the time of connect() (which is now).
1407                  */
1408                 cru2x(td->td_ucred, &unp3->unp_peercred);
1409                 unp3->unp_flags |= UNP_HAVEPC;
1410
1411                 /*
1412                  * The receiver's (server's) credentials are copied from the
1413                  * unp_peercred member of socket on which the former called
1414                  * listen(); uipc_listen() cached that process's credentials
1415                  * at that time so we can use them now.
1416                  */
1417                 KASSERT(unp2->unp_flags & UNP_HAVEPCCACHED,
1418                     ("unp_connect: listener without cached peercred"));
1419                 memcpy(&unp->unp_peercred, &unp2->unp_peercred,
1420                     sizeof(unp->unp_peercred));
1421                 unp->unp_flags |= UNP_HAVEPC;
1422                 if (unp2->unp_flags & UNP_WANTCRED)
1423                         unp3->unp_flags |= UNP_WANTCRED;
1424                 UNP_PCB_UNLOCK(unp3);
1425                 UNP_PCB_UNLOCK(unp2);
1426                 UNP_PCB_UNLOCK(unp);
1427 #ifdef MAC
1428                 mac_socketpeer_set_from_socket(so, so3);
1429                 mac_socketpeer_set_from_socket(so3, so);
1430 #endif
1431
1432                 so2 = so3;
1433         }
1434         unp = sotounpcb(so);
1435         KASSERT(unp != NULL, ("unp_connect: unp == NULL"));
1436         unp2 = sotounpcb(so2);
1437         KASSERT(unp2 != NULL, ("unp_connect: unp2 == NULL"));
1438         UNP_PCB_LOCK(unp);
1439         UNP_PCB_LOCK(unp2);
1440         error = unp_connect2(so, so2, PRU_CONNECT);
1441         UNP_PCB_UNLOCK(unp2);
1442         UNP_PCB_UNLOCK(unp);
1443 bad2:
1444         UNP_LINK_WUNLOCK();
1445 bad:
1446         if (vp != NULL)
1447                 vput(vp);
1448         free(sa, M_SONAME);
1449         UNP_LINK_WLOCK();
1450         UNP_PCB_LOCK(unp);
1451         unp->unp_flags &= ~UNP_CONNECTING;
1452         UNP_PCB_UNLOCK(unp);
1453         return (error);
1454 }
1455
1456 static int
1457 unp_connect2(struct socket *so, struct socket *so2, int req)
1458 {
1459         struct unpcb *unp;
1460         struct unpcb *unp2;
1461
1462         unp = sotounpcb(so);
1463         KASSERT(unp != NULL, ("unp_connect2: unp == NULL"));
1464         unp2 = sotounpcb(so2);
1465         KASSERT(unp2 != NULL, ("unp_connect2: unp2 == NULL"));
1466
1467         UNP_LINK_WLOCK_ASSERT();
1468         UNP_PCB_LOCK_ASSERT(unp);
1469         UNP_PCB_LOCK_ASSERT(unp2);
1470
1471         if (so2->so_type != so->so_type)
1472                 return (EPROTOTYPE);
1473         unp->unp_conn = unp2;
1474
1475         switch (so->so_type) {
1476         case SOCK_DGRAM:
1477                 LIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_reflink);
1478                 soisconnected(so);
1479                 break;
1480
1481         case SOCK_STREAM:
1482         case SOCK_SEQPACKET:
1483                 unp2->unp_conn = unp;
1484                 if (req == PRU_CONNECT &&
1485                     ((unp->unp_flags | unp2->unp_flags) & UNP_CONNWAIT))
1486                         soisconnecting(so);
1487                 else
1488                         soisconnected(so);
1489                 soisconnected(so2);
1490                 break;
1491
1492         default:
1493                 panic("unp_connect2");
1494         }
1495         return (0);
1496 }
1497
1498 static void
1499 unp_disconnect(struct unpcb *unp, struct unpcb *unp2)
1500 {
1501         struct socket *so;
1502
1503         KASSERT(unp2 != NULL, ("unp_disconnect: unp2 == NULL"));
1504
1505         UNP_LINK_WLOCK_ASSERT();
1506         UNP_PCB_LOCK_ASSERT(unp);
1507         UNP_PCB_LOCK_ASSERT(unp2);
1508
1509         unp->unp_conn = NULL;
1510         switch (unp->unp_socket->so_type) {
1511         case SOCK_DGRAM:
1512                 LIST_REMOVE(unp, unp_reflink);
1513                 so = unp->unp_socket;
1514                 SOCK_LOCK(so);
1515                 so->so_state &= ~SS_ISCONNECTED;
1516                 SOCK_UNLOCK(so);
1517                 break;
1518
1519         case SOCK_STREAM:
1520         case SOCK_SEQPACKET:
1521                 soisdisconnected(unp->unp_socket);
1522                 unp2->unp_conn = NULL;
1523                 soisdisconnected(unp2->unp_socket);
1524                 break;
1525         }
1526 }
1527
1528 /*
1529  * unp_pcblist() walks the global list of struct unpcb's to generate a
1530  * pointer list, bumping the refcount on each unpcb.  It then copies them out
1531  * sequentially, validating the generation number on each to see if it has
1532  * been detached.  All of this is necessary because copyout() may sleep on
1533  * disk I/O.
1534  */
1535 static int
1536 unp_pcblist(SYSCTL_HANDLER_ARGS)
1537 {
1538         int error, i, n;
1539         int freeunp;
1540         struct unpcb *unp, **unp_list;
1541         unp_gen_t gencnt;
1542         struct xunpgen *xug;
1543         struct unp_head *head;
1544         struct xunpcb *xu;
1545
1546         switch ((intptr_t)arg1) {
1547         case SOCK_STREAM:
1548                 head = &unp_shead;
1549                 break;
1550
1551         case SOCK_DGRAM:
1552                 head = &unp_dhead;
1553                 break;
1554
1555         case SOCK_SEQPACKET:
1556                 head = &unp_sphead;
1557                 break;
1558
1559         default:
1560                 panic("unp_pcblist: arg1 %d", (int)(intptr_t)arg1);
1561         }
1562
1563         /*
1564          * The process of preparing the PCB list is too time-consuming and
1565          * resource-intensive to repeat twice on every request.
1566          */
1567         if (req->oldptr == NULL) {
1568                 n = unp_count;
1569                 req->oldidx = 2 * (sizeof *xug)
1570                         + (n + n/8) * sizeof(struct xunpcb);
1571                 return (0);
1572         }
1573
1574         if (req->newptr != NULL)
1575                 return (EPERM);
1576
1577         /*
1578          * OK, now we're committed to doing something.
1579          */
1580         xug = malloc(sizeof(*xug), M_TEMP, M_WAITOK);
1581         UNP_LIST_LOCK();
1582         gencnt = unp_gencnt;
1583         n = unp_count;
1584         UNP_LIST_UNLOCK();
1585
1586         xug->xug_len = sizeof *xug;
1587         xug->xug_count = n;
1588         xug->xug_gen = gencnt;
1589         xug->xug_sogen = so_gencnt;
1590         error = SYSCTL_OUT(req, xug, sizeof *xug);
1591         if (error) {
1592                 free(xug, M_TEMP);
1593                 return (error);
1594         }
1595
1596         unp_list = malloc(n * sizeof *unp_list, M_TEMP, M_WAITOK);
1597
1598         UNP_LIST_LOCK();
1599         for (unp = LIST_FIRST(head), i = 0; unp && i < n;
1600              unp = LIST_NEXT(unp, unp_link)) {
1601                 UNP_PCB_LOCK(unp);
1602                 if (unp->unp_gencnt <= gencnt) {
1603                         if (cr_cansee(req->td->td_ucred,
1604                             unp->unp_socket->so_cred)) {
1605                                 UNP_PCB_UNLOCK(unp);
1606                                 continue;
1607                         }
1608                         unp_list[i++] = unp;
1609                         unp->unp_refcount++;
1610                 }
1611                 UNP_PCB_UNLOCK(unp);
1612         }
1613         UNP_LIST_UNLOCK();
1614         n = i;                  /* In case we lost some during malloc. */
1615
1616         error = 0;
1617         xu = malloc(sizeof(*xu), M_TEMP, M_WAITOK | M_ZERO);
1618         for (i = 0; i < n; i++) {
1619                 unp = unp_list[i];
1620                 UNP_PCB_LOCK(unp);
1621                 unp->unp_refcount--;
1622                 if (unp->unp_refcount != 0 && unp->unp_gencnt <= gencnt) {
1623                         xu->xu_len = sizeof *xu;
1624                         xu->xu_unpp = unp;
1625                         /*
1626                          * XXX - need more locking here to protect against
1627                          * connect/disconnect races for SMP.
1628                          */
1629                         if (unp->unp_addr != NULL)
1630                                 bcopy(unp->unp_addr, &xu->xu_addr,
1631                                       unp->unp_addr->sun_len);
1632                         if (unp->unp_conn != NULL &&
1633                             unp->unp_conn->unp_addr != NULL)
1634                                 bcopy(unp->unp_conn->unp_addr,
1635                                       &xu->xu_caddr,
1636                                       unp->unp_conn->unp_addr->sun_len);
1637                         bcopy(unp, &xu->xu_unp, sizeof *unp);
1638                         sotoxsocket(unp->unp_socket, &xu->xu_socket);
1639                         UNP_PCB_UNLOCK(unp);
1640                         error = SYSCTL_OUT(req, xu, sizeof *xu);
1641                 } else {
1642                         freeunp = (unp->unp_refcount == 0);
1643                         UNP_PCB_UNLOCK(unp);
1644                         if (freeunp) {
1645                                 UNP_PCB_LOCK_DESTROY(unp);
1646                                 uma_zfree(unp_zone, unp);
1647                         }
1648                 }
1649         }
1650         free(xu, M_TEMP);
1651         if (!error) {
1652                 /*
1653                  * Give the user an updated idea of our state.  If the
1654                  * generation differs from what we told her before, she knows
1655                  * that something happened while we were processing this
1656                  * request, and it might be necessary to retry.
1657                  */
1658                 xug->xug_gen = unp_gencnt;
1659                 xug->xug_sogen = so_gencnt;
1660                 xug->xug_count = unp_count;
1661                 error = SYSCTL_OUT(req, xug, sizeof *xug);
1662         }
1663         free(unp_list, M_TEMP);
1664         free(xug, M_TEMP);
1665         return (error);
1666 }
1667
1668 SYSCTL_PROC(_net_local_dgram, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD,
1669     (void *)(intptr_t)SOCK_DGRAM, 0, unp_pcblist, "S,xunpcb",
1670     "List of active local datagram sockets");
1671 SYSCTL_PROC(_net_local_stream, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD,
1672     (void *)(intptr_t)SOCK_STREAM, 0, unp_pcblist, "S,xunpcb",
1673     "List of active local stream sockets");
1674 SYSCTL_PROC(_net_local_seqpacket, OID_AUTO, pcblist,
1675     CTLTYPE_OPAQUE | CTLFLAG_RD,
1676     (void *)(intptr_t)SOCK_SEQPACKET, 0, unp_pcblist, "S,xunpcb",
1677     "List of active local seqpacket sockets");
1678
1679 static void
1680 unp_shutdown(struct unpcb *unp)
1681 {
1682         struct unpcb *unp2;
1683         struct socket *so;
1684
1685         UNP_LINK_WLOCK_ASSERT();
1686         UNP_PCB_LOCK_ASSERT(unp);
1687
1688         unp2 = unp->unp_conn;
1689         if ((unp->unp_socket->so_type == SOCK_STREAM ||
1690             (unp->unp_socket->so_type == SOCK_SEQPACKET)) && unp2 != NULL) {
1691                 so = unp2->unp_socket;
1692                 if (so != NULL)
1693                         socantrcvmore(so);
1694         }
1695 }
1696
1697 static void
1698 unp_drop(struct unpcb *unp, int errno)
1699 {
1700         struct socket *so = unp->unp_socket;
1701         struct unpcb *unp2;
1702
1703         UNP_LINK_WLOCK_ASSERT();
1704         UNP_PCB_LOCK_ASSERT(unp);
1705
1706         so->so_error = errno;
1707         unp2 = unp->unp_conn;
1708         if (unp2 == NULL)
1709                 return;
1710         UNP_PCB_LOCK(unp2);
1711         unp_disconnect(unp, unp2);
1712         UNP_PCB_UNLOCK(unp2);
1713 }
1714
1715 static void
1716 unp_freerights(struct filedescent **fdep, int fdcount)
1717 {
1718         struct file *fp;
1719         int i;
1720
1721         KASSERT(fdcount > 0, ("%s: fdcount %d", __func__, fdcount));
1722
1723         for (i = 0; i < fdcount; i++) {
1724                 fp = fdep[i]->fde_file;
1725                 filecaps_free(&fdep[i]->fde_caps);
1726                 unp_discard(fp);
1727         }
1728         free(fdep[0], M_FILECAPS);
1729 }
1730
1731 static int
1732 unp_externalize(struct mbuf *control, struct mbuf **controlp, int flags)
1733 {
1734         struct thread *td = curthread;          /* XXX */
1735         struct cmsghdr *cm = mtod(control, struct cmsghdr *);
1736         int i;
1737         int *fdp;
1738         struct filedesc *fdesc = td->td_proc->p_fd;
1739         struct filedescent **fdep;
1740         void *data;
1741         socklen_t clen = control->m_len, datalen;
1742         int error, newfds;
1743         u_int newlen;
1744
1745         UNP_LINK_UNLOCK_ASSERT();
1746
1747         error = 0;
1748         if (controlp != NULL) /* controlp == NULL => free control messages */
1749                 *controlp = NULL;
1750         while (cm != NULL) {
1751                 if (sizeof(*cm) > clen || cm->cmsg_len > clen) {
1752                         error = EINVAL;
1753                         break;
1754                 }
1755                 data = CMSG_DATA(cm);
1756                 datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data;
1757                 if (cm->cmsg_level == SOL_SOCKET
1758                     && cm->cmsg_type == SCM_RIGHTS) {
1759                         newfds = datalen / sizeof(*fdep);
1760                         if (newfds == 0)
1761                                 goto next;
1762                         fdep = data;
1763
1764                         /* If we're not outputting the descriptors free them. */
1765                         if (error || controlp == NULL) {
1766                                 unp_freerights(fdep, newfds);
1767                                 goto next;
1768                         }
1769                         FILEDESC_XLOCK(fdesc);
1770
1771                         /*
1772                          * Now change each pointer to an fd in the global
1773                          * table to an integer that is the index to the local
1774                          * fd table entry that we set up to point to the
1775                          * global one we are transferring.
1776                          */
1777                         newlen = newfds * sizeof(int);
1778                         *controlp = sbcreatecontrol(NULL, newlen,
1779                             SCM_RIGHTS, SOL_SOCKET);
1780                         if (*controlp == NULL) {
1781                                 FILEDESC_XUNLOCK(fdesc);
1782                                 error = E2BIG;
1783                                 unp_freerights(fdep, newfds);
1784                                 goto next;
1785                         }
1786
1787                         fdp = (int *)
1788                             CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1789                         if (fdallocn(td, 0, fdp, newfds) != 0) {
1790                                 FILEDESC_XUNLOCK(fdesc);
1791                                 error = EMSGSIZE;
1792                                 unp_freerights(fdep, newfds);
1793                                 m_freem(*controlp);
1794                                 *controlp = NULL;
1795                                 goto next;
1796                         }
1797                         for (i = 0; i < newfds; i++, fdp++) {
1798                                 _finstall(fdesc, fdep[i]->fde_file, *fdp,
1799                                     (flags & MSG_CMSG_CLOEXEC) != 0 ? UF_EXCLOSE : 0,
1800                                     &fdep[i]->fde_caps);
1801                                 unp_externalize_fp(fdep[i]->fde_file);
1802                         }
1803                         FILEDESC_XUNLOCK(fdesc);
1804                         free(fdep[0], M_FILECAPS);
1805                 } else {
1806                         /* We can just copy anything else across. */
1807                         if (error || controlp == NULL)
1808                                 goto next;
1809                         *controlp = sbcreatecontrol(NULL, datalen,
1810                             cm->cmsg_type, cm->cmsg_level);
1811                         if (*controlp == NULL) {
1812                                 error = ENOBUFS;
1813                                 goto next;
1814                         }
1815                         bcopy(data,
1816                             CMSG_DATA(mtod(*controlp, struct cmsghdr *)),
1817                             datalen);
1818                 }
1819                 controlp = &(*controlp)->m_next;
1820
1821 next:
1822                 if (CMSG_SPACE(datalen) < clen) {
1823                         clen -= CMSG_SPACE(datalen);
1824                         cm = (struct cmsghdr *)
1825                             ((caddr_t)cm + CMSG_SPACE(datalen));
1826                 } else {
1827                         clen = 0;
1828                         cm = NULL;
1829                 }
1830         }
1831
1832         m_freem(control);
1833         return (error);
1834 }
1835
1836 static void
1837 unp_zone_change(void *tag)
1838 {
1839
1840         uma_zone_set_max(unp_zone, maxsockets);
1841 }
1842
1843 static void
1844 unp_init(void)
1845 {
1846
1847 #ifdef VIMAGE
1848         if (!IS_DEFAULT_VNET(curvnet))
1849                 return;
1850 #endif
1851         unp_zone = uma_zcreate("unpcb", sizeof(struct unpcb), NULL, NULL,
1852             NULL, NULL, UMA_ALIGN_PTR, 0);
1853         if (unp_zone == NULL)
1854                 panic("unp_init");
1855         uma_zone_set_max(unp_zone, maxsockets);
1856         uma_zone_set_warning(unp_zone, "kern.ipc.maxsockets limit reached");
1857         EVENTHANDLER_REGISTER(maxsockets_change, unp_zone_change,
1858             NULL, EVENTHANDLER_PRI_ANY);
1859         LIST_INIT(&unp_dhead);
1860         LIST_INIT(&unp_shead);
1861         LIST_INIT(&unp_sphead);
1862         SLIST_INIT(&unp_defers);
1863         TIMEOUT_TASK_INIT(taskqueue_thread, &unp_gc_task, 0, unp_gc, NULL);
1864         TASK_INIT(&unp_defer_task, 0, unp_process_defers, NULL);
1865         UNP_LINK_LOCK_INIT();
1866         UNP_LIST_LOCK_INIT();
1867         UNP_DEFERRED_LOCK_INIT();
1868 }
1869
1870 static int
1871 unp_internalize(struct mbuf **controlp, struct thread *td)
1872 {
1873         struct mbuf *control = *controlp;
1874         struct proc *p = td->td_proc;
1875         struct filedesc *fdesc = p->p_fd;
1876         struct bintime *bt;
1877         struct cmsghdr *cm = mtod(control, struct cmsghdr *);
1878         struct cmsgcred *cmcred;
1879         struct filedescent *fde, **fdep, *fdev;
1880         struct file *fp;
1881         struct timeval *tv;
1882         int i, *fdp;
1883         void *data;
1884         socklen_t clen = control->m_len, datalen;
1885         int error, oldfds;
1886         u_int newlen;
1887
1888         UNP_LINK_UNLOCK_ASSERT();
1889
1890         error = 0;
1891         *controlp = NULL;
1892         while (cm != NULL) {
1893                 if (sizeof(*cm) > clen || cm->cmsg_level != SOL_SOCKET
1894                     || cm->cmsg_len > clen || cm->cmsg_len < sizeof(*cm)) {
1895                         error = EINVAL;
1896                         goto out;
1897                 }
1898                 data = CMSG_DATA(cm);
1899                 datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data;
1900
1901                 switch (cm->cmsg_type) {
1902                 /*
1903                  * Fill in credential information.
1904                  */
1905                 case SCM_CREDS:
1906                         *controlp = sbcreatecontrol(NULL, sizeof(*cmcred),
1907                             SCM_CREDS, SOL_SOCKET);
1908                         if (*controlp == NULL) {
1909                                 error = ENOBUFS;
1910                                 goto out;
1911                         }
1912                         cmcred = (struct cmsgcred *)
1913                             CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1914                         cmcred->cmcred_pid = p->p_pid;
1915                         cmcred->cmcred_uid = td->td_ucred->cr_ruid;
1916                         cmcred->cmcred_gid = td->td_ucred->cr_rgid;
1917                         cmcred->cmcred_euid = td->td_ucred->cr_uid;
1918                         cmcred->cmcred_ngroups = MIN(td->td_ucred->cr_ngroups,
1919                             CMGROUP_MAX);
1920                         for (i = 0; i < cmcred->cmcred_ngroups; i++)
1921                                 cmcred->cmcred_groups[i] =
1922                                     td->td_ucred->cr_groups[i];
1923                         break;
1924
1925                 case SCM_RIGHTS:
1926                         oldfds = datalen / sizeof (int);
1927                         if (oldfds == 0)
1928                                 break;
1929                         /*
1930                          * Check that all the FDs passed in refer to legal
1931                          * files.  If not, reject the entire operation.
1932                          */
1933                         fdp = data;
1934                         FILEDESC_SLOCK(fdesc);
1935                         for (i = 0; i < oldfds; i++, fdp++) {
1936                                 fp = fget_locked(fdesc, *fdp);
1937                                 if (fp == NULL) {
1938                                         FILEDESC_SUNLOCK(fdesc);
1939                                         error = EBADF;
1940                                         goto out;
1941                                 }
1942                                 if (!(fp->f_ops->fo_flags & DFLAG_PASSABLE)) {
1943                                         FILEDESC_SUNLOCK(fdesc);
1944                                         error = EOPNOTSUPP;
1945                                         goto out;
1946                                 }
1947
1948                         }
1949
1950                         /*
1951                          * Now replace the integer FDs with pointers to the
1952                          * file structure and capability rights.
1953                          */
1954                         newlen = oldfds * sizeof(fdep[0]);
1955                         *controlp = sbcreatecontrol(NULL, newlen,
1956                             SCM_RIGHTS, SOL_SOCKET);
1957                         if (*controlp == NULL) {
1958                                 FILEDESC_SUNLOCK(fdesc);
1959                                 error = E2BIG;
1960                                 goto out;
1961                         }
1962                         fdp = data;
1963                         fdep = (struct filedescent **)
1964                             CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1965                         fdev = malloc(sizeof(*fdev) * oldfds, M_FILECAPS,
1966                             M_WAITOK);
1967                         for (i = 0; i < oldfds; i++, fdev++, fdp++) {
1968                                 fde = &fdesc->fd_ofiles[*fdp];
1969                                 fdep[i] = fdev;
1970                                 fdep[i]->fde_file = fde->fde_file;
1971                                 filecaps_copy(&fde->fde_caps,
1972                                     &fdep[i]->fde_caps);
1973                                 unp_internalize_fp(fdep[i]->fde_file);
1974                         }
1975                         FILEDESC_SUNLOCK(fdesc);
1976                         break;
1977
1978                 case SCM_TIMESTAMP:
1979                         *controlp = sbcreatecontrol(NULL, sizeof(*tv),
1980                             SCM_TIMESTAMP, SOL_SOCKET);
1981                         if (*controlp == NULL) {
1982                                 error = ENOBUFS;
1983                                 goto out;
1984                         }
1985                         tv = (struct timeval *)
1986                             CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1987                         microtime(tv);
1988                         break;
1989
1990                 case SCM_BINTIME:
1991                         *controlp = sbcreatecontrol(NULL, sizeof(*bt),
1992                             SCM_BINTIME, SOL_SOCKET);
1993                         if (*controlp == NULL) {
1994                                 error = ENOBUFS;
1995                                 goto out;
1996                         }
1997                         bt = (struct bintime *)
1998                             CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1999                         bintime(bt);
2000                         break;
2001
2002                 default:
2003                         error = EINVAL;
2004                         goto out;
2005                 }
2006
2007                 controlp = &(*controlp)->m_next;
2008                 if (CMSG_SPACE(datalen) < clen) {
2009                         clen -= CMSG_SPACE(datalen);
2010                         cm = (struct cmsghdr *)
2011                             ((caddr_t)cm + CMSG_SPACE(datalen));
2012                 } else {
2013                         clen = 0;
2014                         cm = NULL;
2015                 }
2016         }
2017
2018 out:
2019         m_freem(control);
2020         return (error);
2021 }
2022
2023 static struct mbuf *
2024 unp_addsockcred(struct thread *td, struct mbuf *control)
2025 {
2026         struct mbuf *m, *n, *n_prev;
2027         struct sockcred *sc;
2028         const struct cmsghdr *cm;
2029         int ngroups;
2030         int i;
2031
2032         ngroups = MIN(td->td_ucred->cr_ngroups, CMGROUP_MAX);
2033         m = sbcreatecontrol(NULL, SOCKCREDSIZE(ngroups), SCM_CREDS, SOL_SOCKET);
2034         if (m == NULL)
2035                 return (control);
2036
2037         sc = (struct sockcred *) CMSG_DATA(mtod(m, struct cmsghdr *));
2038         sc->sc_uid = td->td_ucred->cr_ruid;
2039         sc->sc_euid = td->td_ucred->cr_uid;
2040         sc->sc_gid = td->td_ucred->cr_rgid;
2041         sc->sc_egid = td->td_ucred->cr_gid;
2042         sc->sc_ngroups = ngroups;
2043         for (i = 0; i < sc->sc_ngroups; i++)
2044                 sc->sc_groups[i] = td->td_ucred->cr_groups[i];
2045
2046         /*
2047          * Unlink SCM_CREDS control messages (struct cmsgcred), since just
2048          * created SCM_CREDS control message (struct sockcred) has another
2049          * format.
2050          */
2051         if (control != NULL)
2052                 for (n = control, n_prev = NULL; n != NULL;) {
2053                         cm = mtod(n, struct cmsghdr *);
2054                         if (cm->cmsg_level == SOL_SOCKET &&
2055                             cm->cmsg_type == SCM_CREDS) {
2056                                 if (n_prev == NULL)
2057                                         control = n->m_next;
2058                                 else
2059                                         n_prev->m_next = n->m_next;
2060                                 n = m_free(n);
2061                         } else {
2062                                 n_prev = n;
2063                                 n = n->m_next;
2064                         }
2065                 }
2066
2067         /* Prepend it to the head. */
2068         m->m_next = control;
2069         return (m);
2070 }
2071
2072 static struct unpcb *
2073 fptounp(struct file *fp)
2074 {
2075         struct socket *so;
2076
2077         if (fp->f_type != DTYPE_SOCKET)
2078                 return (NULL);
2079         if ((so = fp->f_data) == NULL)
2080                 return (NULL);
2081         if (so->so_proto->pr_domain != &localdomain)
2082                 return (NULL);
2083         return sotounpcb(so);
2084 }
2085
2086 static void
2087 unp_discard(struct file *fp)
2088 {
2089         struct unp_defer *dr;
2090
2091         if (unp_externalize_fp(fp)) {
2092                 dr = malloc(sizeof(*dr), M_TEMP, M_WAITOK);
2093                 dr->ud_fp = fp;
2094                 UNP_DEFERRED_LOCK();
2095                 SLIST_INSERT_HEAD(&unp_defers, dr, ud_link);
2096                 UNP_DEFERRED_UNLOCK();
2097                 atomic_add_int(&unp_defers_count, 1);
2098                 taskqueue_enqueue(taskqueue_thread, &unp_defer_task);
2099         } else
2100                 (void) closef(fp, (struct thread *)NULL);
2101 }
2102
2103 static void
2104 unp_process_defers(void *arg __unused, int pending)
2105 {
2106         struct unp_defer *dr;
2107         SLIST_HEAD(, unp_defer) drl;
2108         int count;
2109
2110         SLIST_INIT(&drl);
2111         for (;;) {
2112                 UNP_DEFERRED_LOCK();
2113                 if (SLIST_FIRST(&unp_defers) == NULL) {
2114                         UNP_DEFERRED_UNLOCK();
2115                         break;
2116                 }
2117                 SLIST_SWAP(&unp_defers, &drl, unp_defer);
2118                 UNP_DEFERRED_UNLOCK();
2119                 count = 0;
2120                 while ((dr = SLIST_FIRST(&drl)) != NULL) {
2121                         SLIST_REMOVE_HEAD(&drl, ud_link);
2122                         closef(dr->ud_fp, NULL);
2123                         free(dr, M_TEMP);
2124                         count++;
2125                 }
2126                 atomic_add_int(&unp_defers_count, -count);
2127         }
2128 }
2129
2130 static void
2131 unp_internalize_fp(struct file *fp)
2132 {
2133         struct unpcb *unp;
2134
2135         UNP_LINK_WLOCK();
2136         if ((unp = fptounp(fp)) != NULL) {
2137                 unp->unp_file = fp;
2138                 unp->unp_msgcount++;
2139         }
2140         fhold(fp);
2141         unp_rights++;
2142         UNP_LINK_WUNLOCK();
2143 }
2144
2145 static int
2146 unp_externalize_fp(struct file *fp)
2147 {
2148         struct unpcb *unp;
2149         int ret;
2150
2151         UNP_LINK_WLOCK();
2152         if ((unp = fptounp(fp)) != NULL) {
2153                 unp->unp_msgcount--;
2154                 ret = 1;
2155         } else
2156                 ret = 0;
2157         unp_rights--;
2158         UNP_LINK_WUNLOCK();
2159         return (ret);
2160 }
2161
2162 /*
2163  * unp_defer indicates whether additional work has been defered for a future
2164  * pass through unp_gc().  It is thread local and does not require explicit
2165  * synchronization.
2166  */
2167 static int      unp_marked;
2168 static int      unp_unreachable;
2169
2170 static void
2171 unp_accessable(struct filedescent **fdep, int fdcount)
2172 {
2173         struct unpcb *unp;
2174         struct file *fp;
2175         int i;
2176
2177         for (i = 0; i < fdcount; i++) {
2178                 fp = fdep[i]->fde_file;
2179                 if ((unp = fptounp(fp)) == NULL)
2180                         continue;
2181                 if (unp->unp_gcflag & UNPGC_REF)
2182                         continue;
2183                 unp->unp_gcflag &= ~UNPGC_DEAD;
2184                 unp->unp_gcflag |= UNPGC_REF;
2185                 unp_marked++;
2186         }
2187 }
2188
2189 static void
2190 unp_gc_process(struct unpcb *unp)
2191 {
2192         struct socket *soa;
2193         struct socket *so;
2194         struct file *fp;
2195
2196         /* Already processed. */
2197         if (unp->unp_gcflag & UNPGC_SCANNED)
2198                 return;
2199         fp = unp->unp_file;
2200
2201         /*
2202          * Check for a socket potentially in a cycle.  It must be in a
2203          * queue as indicated by msgcount, and this must equal the file
2204          * reference count.  Note that when msgcount is 0 the file is NULL.
2205          */
2206         if ((unp->unp_gcflag & UNPGC_REF) == 0 && fp &&
2207             unp->unp_msgcount != 0 && fp->f_count == unp->unp_msgcount) {
2208                 unp->unp_gcflag |= UNPGC_DEAD;
2209                 unp_unreachable++;
2210                 return;
2211         }
2212
2213         /*
2214          * Mark all sockets we reference with RIGHTS.
2215          */
2216         so = unp->unp_socket;
2217         SOCKBUF_LOCK(&so->so_rcv);
2218         unp_scan(so->so_rcv.sb_mb, unp_accessable);
2219         SOCKBUF_UNLOCK(&so->so_rcv);
2220
2221         /*
2222          * Mark all sockets in our accept queue.
2223          */
2224         ACCEPT_LOCK();
2225         TAILQ_FOREACH(soa, &so->so_comp, so_list) {
2226                 SOCKBUF_LOCK(&soa->so_rcv);
2227                 unp_scan(soa->so_rcv.sb_mb, unp_accessable);
2228                 SOCKBUF_UNLOCK(&soa->so_rcv);
2229         }
2230         ACCEPT_UNLOCK();
2231         unp->unp_gcflag |= UNPGC_SCANNED;
2232 }
2233
2234 static int unp_recycled;
2235 SYSCTL_INT(_net_local, OID_AUTO, recycled, CTLFLAG_RD, &unp_recycled, 0, 
2236     "Number of unreachable sockets claimed by the garbage collector.");
2237
2238 static int unp_taskcount;
2239 SYSCTL_INT(_net_local, OID_AUTO, taskcount, CTLFLAG_RD, &unp_taskcount, 0, 
2240     "Number of times the garbage collector has run.");
2241
2242 static void
2243 unp_gc(__unused void *arg, int pending)
2244 {
2245         struct unp_head *heads[] = { &unp_dhead, &unp_shead, &unp_sphead,
2246                                     NULL };
2247         struct unp_head **head;
2248         struct file *f, **unref;
2249         struct unpcb *unp;
2250         int i, total;
2251
2252         unp_taskcount++;
2253         UNP_LIST_LOCK();
2254         /*
2255          * First clear all gc flags from previous runs.
2256          */
2257         for (head = heads; *head != NULL; head++)
2258                 LIST_FOREACH(unp, *head, unp_link)
2259                         unp->unp_gcflag = 0;
2260
2261         /*
2262          * Scan marking all reachable sockets with UNPGC_REF.  Once a socket
2263          * is reachable all of the sockets it references are reachable.
2264          * Stop the scan once we do a complete loop without discovering
2265          * a new reachable socket.
2266          */
2267         do {
2268                 unp_unreachable = 0;
2269                 unp_marked = 0;
2270                 for (head = heads; *head != NULL; head++)
2271                         LIST_FOREACH(unp, *head, unp_link)
2272                                 unp_gc_process(unp);
2273         } while (unp_marked);
2274         UNP_LIST_UNLOCK();
2275         if (unp_unreachable == 0)
2276                 return;
2277
2278         /*
2279          * Allocate space for a local list of dead unpcbs.
2280          */
2281         unref = malloc(unp_unreachable * sizeof(struct file *),
2282             M_TEMP, M_WAITOK);
2283
2284         /*
2285          * Iterate looking for sockets which have been specifically marked
2286          * as as unreachable and store them locally.
2287          */
2288         UNP_LINK_RLOCK();
2289         UNP_LIST_LOCK();
2290         for (total = 0, head = heads; *head != NULL; head++)
2291                 LIST_FOREACH(unp, *head, unp_link)
2292                         if ((unp->unp_gcflag & UNPGC_DEAD) != 0) {
2293                                 f = unp->unp_file;
2294                                 if (unp->unp_msgcount == 0 || f == NULL ||
2295                                     f->f_count != unp->unp_msgcount)
2296                                         continue;
2297                                 unref[total++] = f;
2298                                 fhold(f);
2299                                 KASSERT(total <= unp_unreachable,
2300                                     ("unp_gc: incorrect unreachable count."));
2301                         }
2302         UNP_LIST_UNLOCK();
2303         UNP_LINK_RUNLOCK();
2304
2305         /*
2306          * Now flush all sockets, free'ing rights.  This will free the
2307          * struct files associated with these sockets but leave each socket
2308          * with one remaining ref.
2309          */
2310         for (i = 0; i < total; i++) {
2311                 struct socket *so;
2312
2313                 so = unref[i]->f_data;
2314                 CURVNET_SET(so->so_vnet);
2315                 sorflush(so);
2316                 CURVNET_RESTORE();
2317         }
2318
2319         /*
2320          * And finally release the sockets so they can be reclaimed.
2321          */
2322         for (i = 0; i < total; i++)
2323                 fdrop(unref[i], NULL);
2324         unp_recycled += total;
2325         free(unref, M_TEMP);
2326 }
2327
2328 static void
2329 unp_dispose(struct mbuf *m)
2330 {
2331
2332         if (m)
2333                 unp_scan(m, unp_freerights);
2334 }
2335
2336 static void
2337 unp_scan(struct mbuf *m0, void (*op)(struct filedescent **, int))
2338 {
2339         struct mbuf *m;
2340         struct cmsghdr *cm;
2341         void *data;
2342         socklen_t clen, datalen;
2343
2344         while (m0 != NULL) {
2345                 for (m = m0; m; m = m->m_next) {
2346                         if (m->m_type != MT_CONTROL)
2347                                 continue;
2348
2349                         cm = mtod(m, struct cmsghdr *);
2350                         clen = m->m_len;
2351
2352                         while (cm != NULL) {
2353                                 if (sizeof(*cm) > clen || cm->cmsg_len > clen)
2354                                         break;
2355
2356                                 data = CMSG_DATA(cm);
2357                                 datalen = (caddr_t)cm + cm->cmsg_len
2358                                     - (caddr_t)data;
2359
2360                                 if (cm->cmsg_level == SOL_SOCKET &&
2361                                     cm->cmsg_type == SCM_RIGHTS) {
2362                                         (*op)(data, datalen /
2363                                             sizeof(struct filedescent *));
2364                                 }
2365
2366                                 if (CMSG_SPACE(datalen) < clen) {
2367                                         clen -= CMSG_SPACE(datalen);
2368                                         cm = (struct cmsghdr *)
2369                                             ((caddr_t)cm + CMSG_SPACE(datalen));
2370                                 } else {
2371                                         clen = 0;
2372                                         cm = NULL;
2373                                 }
2374                         }
2375                 }
2376                 m0 = m0->m_nextpkt;
2377         }
2378 }
2379
2380 /*
2381  * A helper function called by VFS before socket-type vnode reclamation.
2382  * For an active vnode it clears unp_vnode pointer and decrements unp_vnode
2383  * use count.
2384  */
2385 void
2386 vfs_unp_reclaim(struct vnode *vp)
2387 {
2388         struct socket *so;
2389         struct unpcb *unp;
2390         int active;
2391
2392         ASSERT_VOP_ELOCKED(vp, "vfs_unp_reclaim");
2393         KASSERT(vp->v_type == VSOCK,
2394             ("vfs_unp_reclaim: vp->v_type != VSOCK"));
2395
2396         active = 0;
2397         UNP_LINK_WLOCK();
2398         VOP_UNP_CONNECT(vp, &so);
2399         if (so == NULL)
2400                 goto done;
2401         unp = sotounpcb(so);
2402         if (unp == NULL)
2403                 goto done;
2404         UNP_PCB_LOCK(unp);
2405         if (unp->unp_vnode == vp) {
2406                 VOP_UNP_DETACH(vp);
2407                 unp->unp_vnode = NULL;
2408                 active = 1;
2409         }
2410         UNP_PCB_UNLOCK(unp);
2411 done:
2412         UNP_LINK_WUNLOCK();
2413         if (active)
2414                 vunref(vp);
2415 }
2416
2417 #ifdef DDB
2418 static void
2419 db_print_indent(int indent)
2420 {
2421         int i;
2422
2423         for (i = 0; i < indent; i++)
2424                 db_printf(" ");
2425 }
2426
2427 static void
2428 db_print_unpflags(int unp_flags)
2429 {
2430         int comma;
2431
2432         comma = 0;
2433         if (unp_flags & UNP_HAVEPC) {
2434                 db_printf("%sUNP_HAVEPC", comma ? ", " : "");
2435                 comma = 1;
2436         }
2437         if (unp_flags & UNP_HAVEPCCACHED) {
2438                 db_printf("%sUNP_HAVEPCCACHED", comma ? ", " : "");
2439                 comma = 1;
2440         }
2441         if (unp_flags & UNP_WANTCRED) {
2442                 db_printf("%sUNP_WANTCRED", comma ? ", " : "");
2443                 comma = 1;
2444         }
2445         if (unp_flags & UNP_CONNWAIT) {
2446                 db_printf("%sUNP_CONNWAIT", comma ? ", " : "");
2447                 comma = 1;
2448         }
2449         if (unp_flags & UNP_CONNECTING) {
2450                 db_printf("%sUNP_CONNECTING", comma ? ", " : "");
2451                 comma = 1;
2452         }
2453         if (unp_flags & UNP_BINDING) {
2454                 db_printf("%sUNP_BINDING", comma ? ", " : "");
2455                 comma = 1;
2456         }
2457 }
2458
2459 static void
2460 db_print_xucred(int indent, struct xucred *xu)
2461 {
2462         int comma, i;
2463
2464         db_print_indent(indent);
2465         db_printf("cr_version: %u   cr_uid: %u   cr_ngroups: %d\n",
2466             xu->cr_version, xu->cr_uid, xu->cr_ngroups);
2467         db_print_indent(indent);
2468         db_printf("cr_groups: ");
2469         comma = 0;
2470         for (i = 0; i < xu->cr_ngroups; i++) {
2471                 db_printf("%s%u", comma ? ", " : "", xu->cr_groups[i]);
2472                 comma = 1;
2473         }
2474         db_printf("\n");
2475 }
2476
2477 static void
2478 db_print_unprefs(int indent, struct unp_head *uh)
2479 {
2480         struct unpcb *unp;
2481         int counter;
2482
2483         counter = 0;
2484         LIST_FOREACH(unp, uh, unp_reflink) {
2485                 if (counter % 4 == 0)
2486                         db_print_indent(indent);
2487                 db_printf("%p  ", unp);
2488                 if (counter % 4 == 3)
2489                         db_printf("\n");
2490                 counter++;
2491         }
2492         if (counter != 0 && counter % 4 != 0)
2493                 db_printf("\n");
2494 }
2495
2496 DB_SHOW_COMMAND(unpcb, db_show_unpcb)
2497 {
2498         struct unpcb *unp;
2499
2500         if (!have_addr) {
2501                 db_printf("usage: show unpcb <addr>\n");
2502                 return;
2503         }
2504         unp = (struct unpcb *)addr;
2505
2506         db_printf("unp_socket: %p   unp_vnode: %p\n", unp->unp_socket,
2507             unp->unp_vnode);
2508
2509         db_printf("unp_ino: %ju   unp_conn: %p\n", (uintmax_t)unp->unp_ino,
2510             unp->unp_conn);
2511
2512         db_printf("unp_refs:\n");
2513         db_print_unprefs(2, &unp->unp_refs);
2514
2515         /* XXXRW: Would be nice to print the full address, if any. */
2516         db_printf("unp_addr: %p\n", unp->unp_addr);
2517
2518         db_printf("unp_gencnt: %llu\n",
2519             (unsigned long long)unp->unp_gencnt);
2520
2521         db_printf("unp_flags: %x (", unp->unp_flags);
2522         db_print_unpflags(unp->unp_flags);
2523         db_printf(")\n");
2524
2525         db_printf("unp_peercred:\n");
2526         db_print_xucred(2, &unp->unp_peercred);
2527
2528         db_printf("unp_refcount: %u\n", unp->unp_refcount);
2529 }
2530 #endif