Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/uipc_usrreq.c
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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 * distinguish datagram size limits from flow control limits in SEQPACKET 55 * rethink name space problems 56 * need a proper out-of-band 57 */ 58 59 #include <sys/cdefs.h> 60 __FBSDID("$FreeBSD: releng/10.0/sys/kern/uipc_usrreq.c 255478 2013-09-11 18:22:30Z glebius $"); 61 62 #include "opt_ddb.h" 63 64 #include <sys/param.h> 65 #include <sys/capability.h> 66 #include <sys/domain.h> 67 #include <sys/fcntl.h> 68 #include <sys/malloc.h> /* XXX must be before <sys/file.h> */ 69 #include <sys/eventhandler.h> 70 #include <sys/file.h> 71 #include <sys/filedesc.h> 72 #include <sys/kernel.h> 73 #include <sys/lock.h> 74 #include <sys/mbuf.h> 75 #include <sys/mount.h> 76 #include <sys/mutex.h> 77 #include <sys/namei.h> 78 #include <sys/proc.h> 79 #include <sys/protosw.h> 80 #include <sys/queue.h> 81 #include <sys/resourcevar.h> 82 #include <sys/rwlock.h> 83 #include <sys/socket.h> 84 #include <sys/socketvar.h> 85 #include <sys/signalvar.h> 86 #include <sys/stat.h> 87 #include <sys/sx.h> 88 #include <sys/sysctl.h> 89 #include <sys/systm.h> 90 #include <sys/taskqueue.h> 91 #include <sys/un.h> 92 #include <sys/unpcb.h> 93 #include <sys/vnode.h> 94 95 #include <net/vnet.h> 96 97 #ifdef DDB 98 #include <ddb/ddb.h> 99 #endif 100 101 #include <security/mac/mac_framework.h> 102 103 #include <vm/uma.h> 104 105 MALLOC_DECLARE(M_FILECAPS); 106 107 /* 108 * Locking key: 109 * (l) Locked using list lock 110 * (g) Locked using linkage lock 111 */ 112 113 static uma_zone_t unp_zone; 114 static unp_gen_t unp_gencnt; /* (l) */ 115 static u_int unp_count; /* (l) Count of local sockets. */ 116 static ino_t unp_ino; /* Prototype for fake inode numbers. */ 117 static int unp_rights; /* (g) File descriptors in flight. */ 118 static struct unp_head unp_shead; /* (l) List of stream sockets. */ 119 static struct unp_head unp_dhead; /* (l) List of datagram sockets. */ 120 static struct unp_head unp_sphead; /* (l) List of seqpacket sockets. */ 121 122 struct unp_defer { 123 SLIST_ENTRY(unp_defer) ud_link; 124 struct file *ud_fp; 125 }; 126 static SLIST_HEAD(, unp_defer) unp_defers; 127 static int unp_defers_count; 128 129 static const struct sockaddr sun_noname = { sizeof(sun_noname), AF_LOCAL }; 130 131 /* 132 * Garbage collection of cyclic file descriptor/socket references occurs 133 * asynchronously in a taskqueue context in order to avoid recursion and 134 * reentrance in the UNIX domain socket, file descriptor, and socket layer 135 * code. See unp_gc() for a full description. 136 */ 137 static struct timeout_task unp_gc_task; 138 139 /* 140 * The close of unix domain sockets attached as SCM_RIGHTS is 141 * postponed to the taskqueue, to avoid arbitrary recursion depth. 142 * The attached sockets might have another sockets attached. 143 */ 144 static struct task unp_defer_task; 145 146 /* 147 * Both send and receive buffers are allocated PIPSIZ bytes of buffering for 148 * stream sockets, although the total for sender and receiver is actually 149 * only PIPSIZ. 150 * 151 * Datagram sockets really use the sendspace as the maximum datagram size, 152 * and don't really want to reserve the sendspace. Their recvspace should be 153 * large enough for at least one max-size datagram plus address. 154 */ 155 #ifndef PIPSIZ 156 #define PIPSIZ 8192 157 #endif 158 static u_long unpst_sendspace = PIPSIZ; 159 static u_long unpst_recvspace = PIPSIZ; 160 static u_long unpdg_sendspace = 2*1024; /* really max datagram size */ 161 static u_long unpdg_recvspace = 4*1024; 162 static u_long unpsp_sendspace = PIPSIZ; /* really max datagram size */ 163 static u_long unpsp_recvspace = PIPSIZ; 164 165 static SYSCTL_NODE(_net, PF_LOCAL, local, CTLFLAG_RW, 0, "Local domain"); 166 static SYSCTL_NODE(_net_local, SOCK_STREAM, stream, CTLFLAG_RW, 0, 167 "SOCK_STREAM"); 168 static SYSCTL_NODE(_net_local, SOCK_DGRAM, dgram, CTLFLAG_RW, 0, "SOCK_DGRAM"); 169 static SYSCTL_NODE(_net_local, SOCK_SEQPACKET, seqpacket, CTLFLAG_RW, 0, 170 "SOCK_SEQPACKET"); 171 172 SYSCTL_ULONG(_net_local_stream, OID_AUTO, sendspace, CTLFLAG_RW, 173 &unpst_sendspace, 0, "Default stream send space."); 174 SYSCTL_ULONG(_net_local_stream, OID_AUTO, recvspace, CTLFLAG_RW, 175 &unpst_recvspace, 0, "Default stream receive space."); 176 SYSCTL_ULONG(_net_local_dgram, OID_AUTO, maxdgram, CTLFLAG_RW, 177 &unpdg_sendspace, 0, "Default datagram send space."); 178 SYSCTL_ULONG(_net_local_dgram, OID_AUTO, recvspace, CTLFLAG_RW, 179 &unpdg_recvspace, 0, "Default datagram receive space."); 180 SYSCTL_ULONG(_net_local_seqpacket, OID_AUTO, maxseqpacket, CTLFLAG_RW, 181 &unpsp_sendspace, 0, "Default seqpacket send space."); 182 SYSCTL_ULONG(_net_local_seqpacket, OID_AUTO, recvspace, CTLFLAG_RW, 183 &unpsp_recvspace, 0, "Default seqpacket receive space."); 184 SYSCTL_INT(_net_local, OID_AUTO, inflight, CTLFLAG_RD, &unp_rights, 0, 185 "File descriptors in flight."); 186 SYSCTL_INT(_net_local, OID_AUTO, deferred, CTLFLAG_RD, 187 &unp_defers_count, 0, 188 "File descriptors deferred to taskqueue for close."); 189 190 /* 191 * Locking and synchronization: 192 * 193 * Three types of locks exit in the local domain socket implementation: a 194 * global list mutex, a global linkage rwlock, and per-unpcb mutexes. Of the 195 * global locks, the list lock protects the socket count, global generation 196 * number, and stream/datagram global lists. The linkage lock protects the 197 * interconnection of unpcbs, the v_socket and unp_vnode pointers, and can be 198 * held exclusively over the acquisition of multiple unpcb locks to prevent 199 * deadlock. 200 * 201 * UNIX domain sockets each have an unpcb hung off of their so_pcb pointer, 202 * allocated in pru_attach() and freed in pru_detach(). The validity of that 203 * pointer is an invariant, so no lock is required to dereference the so_pcb 204 * pointer if a valid socket reference is held by the caller. In practice, 205 * this is always true during operations performed on a socket. Each unpcb 206 * has a back-pointer to its socket, unp_socket, which will be stable under 207 * the same circumstances. 208 * 209 * This pointer may only be safely dereferenced as long as a valid reference 210 * to the unpcb is held. Typically, this reference will be from the socket, 211 * or from another unpcb when the referring unpcb's lock is held (in order 212 * that the reference not be invalidated during use). For example, to follow 213 * unp->unp_conn->unp_socket, you need unlock the lock on unp, not unp_conn, 214 * as unp_socket remains valid as long as the reference to unp_conn is valid. 215 * 216 * Fields of unpcbss are locked using a per-unpcb lock, unp_mtx. Individual 217 * atomic reads without the lock may be performed "lockless", but more 218 * complex reads and read-modify-writes require the mutex to be held. No 219 * lock order is defined between unpcb locks -- multiple unpcb locks may be 220 * acquired at the same time only when holding the linkage rwlock 221 * exclusively, which prevents deadlocks. 222 * 223 * Blocking with UNIX domain sockets is a tricky issue: unlike most network 224 * protocols, bind() is a non-atomic operation, and connect() requires 225 * potential sleeping in the protocol, due to potentially waiting on local or 226 * distributed file systems. We try to separate "lookup" operations, which 227 * may sleep, and the IPC operations themselves, which typically can occur 228 * with relative atomicity as locks can be held over the entire operation. 229 * 230 * Another tricky issue is simultaneous multi-threaded or multi-process 231 * access to a single UNIX domain socket. These are handled by the flags 232 * UNP_CONNECTING and UNP_BINDING, which prevent concurrent connecting or 233 * binding, both of which involve dropping UNIX domain socket locks in order 234 * to perform namei() and other file system operations. 235 */ 236 static struct rwlock unp_link_rwlock; 237 static struct mtx unp_list_lock; 238 static struct mtx unp_defers_lock; 239 240 #define UNP_LINK_LOCK_INIT() rw_init(&unp_link_rwlock, \ 241 "unp_link_rwlock") 242 243 #define UNP_LINK_LOCK_ASSERT() rw_assert(&unp_link_rwlock, \ 244 RA_LOCKED) 245 #define UNP_LINK_UNLOCK_ASSERT() rw_assert(&unp_link_rwlock, \ 246 RA_UNLOCKED) 247 248 #define UNP_LINK_RLOCK() rw_rlock(&unp_link_rwlock) 249 #define UNP_LINK_RUNLOCK() rw_runlock(&unp_link_rwlock) 250 #define UNP_LINK_WLOCK() rw_wlock(&unp_link_rwlock) 251 #define UNP_LINK_WUNLOCK() rw_wunlock(&unp_link_rwlock) 252 #define UNP_LINK_WLOCK_ASSERT() rw_assert(&unp_link_rwlock, \ 253 RA_WLOCKED) 254 255 #define UNP_LIST_LOCK_INIT() mtx_init(&unp_list_lock, \ 256 "unp_list_lock", NULL, MTX_DEF) 257 #define UNP_LIST_LOCK() mtx_lock(&unp_list_lock) 258 #define UNP_LIST_UNLOCK() mtx_unlock(&unp_list_lock) 259 260 #define UNP_DEFERRED_LOCK_INIT() mtx_init(&unp_defers_lock, \ 261 "unp_defer", NULL, MTX_DEF) 262 #define UNP_DEFERRED_LOCK() mtx_lock(&unp_defers_lock) 263 #define UNP_DEFERRED_UNLOCK() mtx_unlock(&unp_defers_lock) 264 265 #define UNP_PCB_LOCK_INIT(unp) mtx_init(&(unp)->unp_mtx, \ 266 "unp_mtx", "unp_mtx", \ 267 MTX_DUPOK|MTX_DEF|MTX_RECURSE) 268 #define UNP_PCB_LOCK_DESTROY(unp) mtx_destroy(&(unp)->unp_mtx) 269 #define UNP_PCB_LOCK(unp) mtx_lock(&(unp)->unp_mtx) 270 #define UNP_PCB_UNLOCK(unp) mtx_unlock(&(unp)->unp_mtx) 271 #define UNP_PCB_LOCK_ASSERT(unp) mtx_assert(&(unp)->unp_mtx, MA_OWNED) 272 273 static int uipc_connect2(struct socket *, struct socket *); 274 static int uipc_ctloutput(struct socket *, struct sockopt *); 275 static int unp_connect(struct socket *, struct sockaddr *, 276 struct thread *); 277 static int unp_connectat(int, struct socket *, struct sockaddr *, 278 struct thread *); 279 static int unp_connect2(struct socket *so, struct socket *so2, int); 280 static void unp_disconnect(struct unpcb *unp, struct unpcb *unp2); 281 static void unp_dispose(struct mbuf *); 282 static void unp_shutdown(struct unpcb *); 283 static void unp_drop(struct unpcb *, int); 284 static void unp_gc(__unused void *, int); 285 static void unp_scan(struct mbuf *, void (*)(struct filedescent **, int)); 286 static void unp_discard(struct file *); 287 static void unp_freerights(struct filedescent **, int); 288 static void unp_init(void); 289 static int unp_internalize(struct mbuf **, struct thread *); 290 static void unp_internalize_fp(struct file *); 291 static int unp_externalize(struct mbuf *, struct mbuf **, int); 292 static int unp_externalize_fp(struct file *); 293 static struct mbuf *unp_addsockcred(struct thread *, struct mbuf *); 294 static void unp_process_defers(void * __unused, int); 295 296 /* 297 * Definitions of protocols supported in the LOCAL domain. 298 */ 299 static struct domain localdomain; 300 static struct pr_usrreqs uipc_usrreqs_dgram, uipc_usrreqs_stream; 301 static struct pr_usrreqs uipc_usrreqs_seqpacket; 302 static struct protosw localsw[] = { 303 { 304 .pr_type = SOCK_STREAM, 305 .pr_domain = &localdomain, 306 .pr_flags = PR_CONNREQUIRED|PR_WANTRCVD|PR_RIGHTS, 307 .pr_ctloutput = &uipc_ctloutput, 308 .pr_usrreqs = &uipc_usrreqs_stream 309 }, 310 { 311 .pr_type = SOCK_DGRAM, 312 .pr_domain = &localdomain, 313 .pr_flags = PR_ATOMIC|PR_ADDR|PR_RIGHTS, 314 .pr_ctloutput = &uipc_ctloutput, 315 .pr_usrreqs = &uipc_usrreqs_dgram 316 }, 317 { 318 .pr_type = SOCK_SEQPACKET, 319 .pr_domain = &localdomain, 320 321 /* 322 * XXXRW: For now, PR_ADDR because soreceive will bump into them 323 * due to our use of sbappendaddr. A new sbappend variants is needed 324 * that supports both atomic record writes and control data. 325 */ 326 .pr_flags = PR_ADDR|PR_ATOMIC|PR_CONNREQUIRED|PR_WANTRCVD| 327 PR_RIGHTS, 328 .pr_ctloutput = &uipc_ctloutput, 329 .pr_usrreqs = &uipc_usrreqs_seqpacket, 330 }, 331 }; 332 333 static struct domain localdomain = { 334 .dom_family = AF_LOCAL, 335 .dom_name = "local", 336 .dom_init = unp_init, 337 .dom_externalize = unp_externalize, 338 .dom_dispose = unp_dispose, 339 .dom_protosw = localsw, 340 .dom_protoswNPROTOSW = &localsw[sizeof(localsw)/sizeof(localsw[0])] 341 }; 342 DOMAIN_SET(local); 343 344 static void 345 uipc_abort(struct socket *so) 346 { 347 struct unpcb *unp, *unp2; 348 349 unp = sotounpcb(so); 350 KASSERT(unp != NULL, ("uipc_abort: unp == NULL")); 351 352 UNP_LINK_WLOCK(); 353 UNP_PCB_LOCK(unp); 354 unp2 = unp->unp_conn; 355 if (unp2 != NULL) { 356 UNP_PCB_LOCK(unp2); 357 unp_drop(unp2, ECONNABORTED); 358 UNP_PCB_UNLOCK(unp2); 359 } 360 UNP_PCB_UNLOCK(unp); 361 UNP_LINK_WUNLOCK(); 362 } 363 364 static int 365 uipc_accept(struct socket *so, struct sockaddr **nam) 366 { 367 struct unpcb *unp, *unp2; 368 const struct sockaddr *sa; 369 370 /* 371 * Pass back name of connected socket, if it was bound and we are 372 * still connected (our peer may have closed already!). 373 */ 374 unp = sotounpcb(so); 375 KASSERT(unp != NULL, ("uipc_accept: unp == NULL")); 376 377 *nam = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK); 378 UNP_LINK_RLOCK(); 379 unp2 = unp->unp_conn; 380 if (unp2 != NULL && unp2->unp_addr != NULL) { 381 UNP_PCB_LOCK(unp2); 382 sa = (struct sockaddr *) unp2->unp_addr; 383 bcopy(sa, *nam, sa->sa_len); 384 UNP_PCB_UNLOCK(unp2); 385 } else { 386 sa = &sun_noname; 387 bcopy(sa, *nam, sa->sa_len); 388 } 389 UNP_LINK_RUNLOCK(); 390 return (0); 391 } 392 393 static int 394 uipc_attach(struct socket *so, int proto, struct thread *td) 395 { 396 u_long sendspace, recvspace; 397 struct unpcb *unp; 398 int error; 399 400 KASSERT(so->so_pcb == NULL, ("uipc_attach: so_pcb != NULL")); 401 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 402 switch (so->so_type) { 403 case SOCK_STREAM: 404 sendspace = unpst_sendspace; 405 recvspace = unpst_recvspace; 406 break; 407 408 case SOCK_DGRAM: 409 sendspace = unpdg_sendspace; 410 recvspace = unpdg_recvspace; 411 break; 412 413 case SOCK_SEQPACKET: 414 sendspace = unpsp_sendspace; 415 recvspace = unpsp_recvspace; 416 break; 417 418 default: 419 panic("uipc_attach"); 420 } 421 error = soreserve(so, sendspace, recvspace); 422 if (error) 423 return (error); 424 } 425 unp = uma_zalloc(unp_zone, M_NOWAIT | M_ZERO); 426 if (unp == NULL) 427 return (ENOBUFS); 428 LIST_INIT(&unp->unp_refs); 429 UNP_PCB_LOCK_INIT(unp); 430 unp->unp_socket = so; 431 so->so_pcb = unp; 432 unp->unp_refcount = 1; 433 434 UNP_LIST_LOCK(); 435 unp->unp_gencnt = ++unp_gencnt; 436 unp_count++; 437 switch (so->so_type) { 438 case SOCK_STREAM: 439 LIST_INSERT_HEAD(&unp_shead, unp, unp_link); 440 break; 441 442 case SOCK_DGRAM: 443 LIST_INSERT_HEAD(&unp_dhead, unp, unp_link); 444 break; 445 446 case SOCK_SEQPACKET: 447 LIST_INSERT_HEAD(&unp_sphead, unp, unp_link); 448 break; 449 450 default: 451 panic("uipc_attach"); 452 } 453 UNP_LIST_UNLOCK(); 454 455 return (0); 456 } 457 458 static int 459 uipc_bindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) 460 { 461 struct sockaddr_un *soun = (struct sockaddr_un *)nam; 462 struct vattr vattr; 463 int error, namelen; 464 struct nameidata nd; 465 struct unpcb *unp; 466 struct vnode *vp; 467 struct mount *mp; 468 cap_rights_t rights; 469 char *buf; 470 471 unp = sotounpcb(so); 472 KASSERT(unp != NULL, ("uipc_bind: unp == NULL")); 473 474 if (soun->sun_len > sizeof(struct sockaddr_un)) 475 return (EINVAL); 476 namelen = soun->sun_len - offsetof(struct sockaddr_un, sun_path); 477 if (namelen <= 0) 478 return (EINVAL); 479 480 /* 481 * We don't allow simultaneous bind() calls on a single UNIX domain 482 * socket, so flag in-progress operations, and return an error if an 483 * operation is already in progress. 484 * 485 * Historically, we have not allowed a socket to be rebound, so this 486 * also returns an error. Not allowing re-binding simplifies the 487 * implementation and avoids a great many possible failure modes. 488 */ 489 UNP_PCB_LOCK(unp); 490 if (unp->unp_vnode != NULL) { 491 UNP_PCB_UNLOCK(unp); 492 return (EINVAL); 493 } 494 if (unp->unp_flags & UNP_BINDING) { 495 UNP_PCB_UNLOCK(unp); 496 return (EALREADY); 497 } 498 unp->unp_flags |= UNP_BINDING; 499 UNP_PCB_UNLOCK(unp); 500 501 buf = malloc(namelen + 1, M_TEMP, M_WAITOK); 502 bcopy(soun->sun_path, buf, namelen); 503 buf[namelen] = 0; 504 505 restart: 506 NDINIT_ATRIGHTS(&nd, CREATE, NOFOLLOW | LOCKPARENT | SAVENAME, 507 UIO_SYSSPACE, buf, fd, cap_rights_init(&rights, CAP_BINDAT), td); 508 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 509 error = namei(&nd); 510 if (error) 511 goto error; 512 vp = nd.ni_vp; 513 if (vp != NULL || vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) { 514 NDFREE(&nd, NDF_ONLY_PNBUF); 515 if (nd.ni_dvp == vp) 516 vrele(nd.ni_dvp); 517 else 518 vput(nd.ni_dvp); 519 if (vp != NULL) { 520 vrele(vp); 521 error = EADDRINUSE; 522 goto error; 523 } 524 error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH); 525 if (error) 526 goto error; 527 goto restart; 528 } 529 VATTR_NULL(&vattr); 530 vattr.va_type = VSOCK; 531 vattr.va_mode = (ACCESSPERMS & ~td->td_proc->p_fd->fd_cmask); 532 #ifdef MAC 533 error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd, 534 &vattr); 535 #endif 536 if (error == 0) 537 error = VOP_CREATE(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr); 538 NDFREE(&nd, NDF_ONLY_PNBUF); 539 vput(nd.ni_dvp); 540 if (error) { 541 vn_finished_write(mp); 542 goto error; 543 } 544 vp = nd.ni_vp; 545 ASSERT_VOP_ELOCKED(vp, "uipc_bind"); 546 soun = (struct sockaddr_un *)sodupsockaddr(nam, M_WAITOK); 547 548 UNP_LINK_WLOCK(); 549 UNP_PCB_LOCK(unp); 550 VOP_UNP_BIND(vp, unp->unp_socket); 551 unp->unp_vnode = vp; 552 unp->unp_addr = soun; 553 unp->unp_flags &= ~UNP_BINDING; 554 UNP_PCB_UNLOCK(unp); 555 UNP_LINK_WUNLOCK(); 556 VOP_UNLOCK(vp, 0); 557 vn_finished_write(mp); 558 free(buf, M_TEMP); 559 return (0); 560 561 error: 562 UNP_PCB_LOCK(unp); 563 unp->unp_flags &= ~UNP_BINDING; 564 UNP_PCB_UNLOCK(unp); 565 free(buf, M_TEMP); 566 return (error); 567 } 568 569 static int 570 uipc_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 571 { 572 573 return (uipc_bindat(AT_FDCWD, so, nam, td)); 574 } 575 576 static int 577 uipc_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 578 { 579 int error; 580 581 KASSERT(td == curthread, ("uipc_connect: td != curthread")); 582 UNP_LINK_WLOCK(); 583 error = unp_connect(so, nam, td); 584 UNP_LINK_WUNLOCK(); 585 return (error); 586 } 587 588 static int 589 uipc_connectat(int fd, struct socket *so, struct sockaddr *nam, 590 struct thread *td) 591 { 592 int error; 593 594 KASSERT(td == curthread, ("uipc_connectat: td != curthread")); 595 UNP_LINK_WLOCK(); 596 error = unp_connectat(fd, so, nam, td); 597 UNP_LINK_WUNLOCK(); 598 return (error); 599 } 600 601 static void 602 uipc_close(struct socket *so) 603 { 604 struct unpcb *unp, *unp2; 605 606 unp = sotounpcb(so); 607 KASSERT(unp != NULL, ("uipc_close: unp == NULL")); 608 609 UNP_LINK_WLOCK(); 610 UNP_PCB_LOCK(unp); 611 unp2 = unp->unp_conn; 612 if (unp2 != NULL) { 613 UNP_PCB_LOCK(unp2); 614 unp_disconnect(unp, unp2); 615 UNP_PCB_UNLOCK(unp2); 616 } 617 UNP_PCB_UNLOCK(unp); 618 UNP_LINK_WUNLOCK(); 619 } 620 621 static int 622 uipc_connect2(struct socket *so1, struct socket *so2) 623 { 624 struct unpcb *unp, *unp2; 625 int error; 626 627 UNP_LINK_WLOCK(); 628 unp = so1->so_pcb; 629 KASSERT(unp != NULL, ("uipc_connect2: unp == NULL")); 630 UNP_PCB_LOCK(unp); 631 unp2 = so2->so_pcb; 632 KASSERT(unp2 != NULL, ("uipc_connect2: unp2 == NULL")); 633 UNP_PCB_LOCK(unp2); 634 error = unp_connect2(so1, so2, PRU_CONNECT2); 635 UNP_PCB_UNLOCK(unp2); 636 UNP_PCB_UNLOCK(unp); 637 UNP_LINK_WUNLOCK(); 638 return (error); 639 } 640 641 static void 642 uipc_detach(struct socket *so) 643 { 644 struct unpcb *unp, *unp2; 645 struct sockaddr_un *saved_unp_addr; 646 struct vnode *vp; 647 int freeunp, local_unp_rights; 648 649 unp = sotounpcb(so); 650 KASSERT(unp != NULL, ("uipc_detach: unp == NULL")); 651 652 UNP_LINK_WLOCK(); 653 UNP_LIST_LOCK(); 654 UNP_PCB_LOCK(unp); 655 LIST_REMOVE(unp, unp_link); 656 unp->unp_gencnt = ++unp_gencnt; 657 --unp_count; 658 UNP_LIST_UNLOCK(); 659 660 /* 661 * XXXRW: Should assert vp->v_socket == so. 662 */ 663 if ((vp = unp->unp_vnode) != NULL) { 664 VOP_UNP_DETACH(vp); 665 unp->unp_vnode = NULL; 666 } 667 unp2 = unp->unp_conn; 668 if (unp2 != NULL) { 669 UNP_PCB_LOCK(unp2); 670 unp_disconnect(unp, unp2); 671 UNP_PCB_UNLOCK(unp2); 672 } 673 674 /* 675 * We hold the linkage lock exclusively, so it's OK to acquire 676 * multiple pcb locks at a time. 677 */ 678 while (!LIST_EMPTY(&unp->unp_refs)) { 679 struct unpcb *ref = LIST_FIRST(&unp->unp_refs); 680 681 UNP_PCB_LOCK(ref); 682 unp_drop(ref, ECONNRESET); 683 UNP_PCB_UNLOCK(ref); 684 } 685 local_unp_rights = unp_rights; 686 UNP_LINK_WUNLOCK(); 687 unp->unp_socket->so_pcb = NULL; 688 saved_unp_addr = unp->unp_addr; 689 unp->unp_addr = NULL; 690 unp->unp_refcount--; 691 freeunp = (unp->unp_refcount == 0); 692 if (saved_unp_addr != NULL) 693 free(saved_unp_addr, M_SONAME); 694 if (freeunp) { 695 UNP_PCB_LOCK_DESTROY(unp); 696 uma_zfree(unp_zone, unp); 697 } else 698 UNP_PCB_UNLOCK(unp); 699 if (vp) 700 vrele(vp); 701 if (local_unp_rights) 702 taskqueue_enqueue_timeout(taskqueue_thread, &unp_gc_task, -1); 703 } 704 705 static int 706 uipc_disconnect(struct socket *so) 707 { 708 struct unpcb *unp, *unp2; 709 710 unp = sotounpcb(so); 711 KASSERT(unp != NULL, ("uipc_disconnect: unp == NULL")); 712 713 UNP_LINK_WLOCK(); 714 UNP_PCB_LOCK(unp); 715 unp2 = unp->unp_conn; 716 if (unp2 != NULL) { 717 UNP_PCB_LOCK(unp2); 718 unp_disconnect(unp, unp2); 719 UNP_PCB_UNLOCK(unp2); 720 } 721 UNP_PCB_UNLOCK(unp); 722 UNP_LINK_WUNLOCK(); 723 return (0); 724 } 725 726 static int 727 uipc_listen(struct socket *so, int backlog, struct thread *td) 728 { 729 struct unpcb *unp; 730 int error; 731 732 unp = sotounpcb(so); 733 KASSERT(unp != NULL, ("uipc_listen: unp == NULL")); 734 735 UNP_PCB_LOCK(unp); 736 if (unp->unp_vnode == NULL) { 737 UNP_PCB_UNLOCK(unp); 738 return (EINVAL); 739 } 740 741 SOCK_LOCK(so); 742 error = solisten_proto_check(so); 743 if (error == 0) { 744 cru2x(td->td_ucred, &unp->unp_peercred); 745 unp->unp_flags |= UNP_HAVEPCCACHED; 746 solisten_proto(so, backlog); 747 } 748 SOCK_UNLOCK(so); 749 UNP_PCB_UNLOCK(unp); 750 return (error); 751 } 752 753 static int 754 uipc_peeraddr(struct socket *so, struct sockaddr **nam) 755 { 756 struct unpcb *unp, *unp2; 757 const struct sockaddr *sa; 758 759 unp = sotounpcb(so); 760 KASSERT(unp != NULL, ("uipc_peeraddr: unp == NULL")); 761 762 *nam = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK); 763 UNP_LINK_RLOCK(); 764 /* 765 * XXX: It seems that this test always fails even when connection is 766 * established. So, this else clause is added as workaround to 767 * return PF_LOCAL sockaddr. 768 */ 769 unp2 = unp->unp_conn; 770 if (unp2 != NULL) { 771 UNP_PCB_LOCK(unp2); 772 if (unp2->unp_addr != NULL) 773 sa = (struct sockaddr *) unp2->unp_addr; 774 else 775 sa = &sun_noname; 776 bcopy(sa, *nam, sa->sa_len); 777 UNP_PCB_UNLOCK(unp2); 778 } else { 779 sa = &sun_noname; 780 bcopy(sa, *nam, sa->sa_len); 781 } 782 UNP_LINK_RUNLOCK(); 783 return (0); 784 } 785 786 static int 787 uipc_rcvd(struct socket *so, int flags) 788 { 789 struct unpcb *unp, *unp2; 790 struct socket *so2; 791 u_int mbcnt, sbcc; 792 u_long newhiwat; 793 794 unp = sotounpcb(so); 795 KASSERT(unp != NULL, ("uipc_rcvd: unp == NULL")); 796 797 if (so->so_type != SOCK_STREAM && so->so_type != SOCK_SEQPACKET) 798 panic("uipc_rcvd socktype %d", 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 = so->so_rcv.sb_cc; 813 SOCKBUF_UNLOCK(&so->so_rcv); 814 UNP_PCB_LOCK(unp); 815 unp2 = unp->unp_conn; 816 if (unp2 == NULL) { 817 UNP_PCB_UNLOCK(unp); 818 return (0); 819 } 820 so2 = unp2->unp_socket; 821 SOCKBUF_LOCK(&so2->so_snd); 822 so2->so_snd.sb_mbmax += unp->unp_mbcnt - mbcnt; 823 newhiwat = so2->so_snd.sb_hiwat + unp->unp_cc - sbcc; 824 (void)chgsbsize(so2->so_cred->cr_uidinfo, &so2->so_snd.sb_hiwat, 825 newhiwat, RLIM_INFINITY); 826 sowwakeup_locked(so2); 827 unp->unp_mbcnt = mbcnt; 828 unp->unp_cc = sbcc; 829 UNP_PCB_UNLOCK(unp); 830 return (0); 831 } 832 833 static int 834 uipc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 835 struct mbuf *control, struct thread *td) 836 { 837 struct unpcb *unp, *unp2; 838 struct socket *so2; 839 u_int mbcnt_delta, sbcc; 840 u_int newhiwat; 841 int error = 0; 842 843 unp = sotounpcb(so); 844 KASSERT(unp != NULL, ("uipc_send: unp == NULL")); 845 846 if (flags & PRUS_OOB) { 847 error = EOPNOTSUPP; 848 goto release; 849 } 850 if (control != NULL && (error = unp_internalize(&control, td))) 851 goto release; 852 if ((nam != NULL) || (flags & PRUS_EOF)) 853 UNP_LINK_WLOCK(); 854 else 855 UNP_LINK_RLOCK(); 856 switch (so->so_type) { 857 case SOCK_DGRAM: 858 { 859 const struct sockaddr *from; 860 861 unp2 = unp->unp_conn; 862 if (nam != NULL) { 863 UNP_LINK_WLOCK_ASSERT(); 864 if (unp2 != NULL) { 865 error = EISCONN; 866 break; 867 } 868 error = unp_connect(so, nam, td); 869 if (error) 870 break; 871 unp2 = unp->unp_conn; 872 } 873 874 /* 875 * Because connect() and send() are non-atomic in a sendto() 876 * with a target address, it's possible that the socket will 877 * have disconnected before the send() can run. In that case 878 * return the slightly counter-intuitive but otherwise 879 * correct error that the socket is not connected. 880 */ 881 if (unp2 == NULL) { 882 error = ENOTCONN; 883 break; 884 } 885 /* Lockless read. */ 886 if (unp2->unp_flags & UNP_WANTCRED) 887 control = unp_addsockcred(td, control); 888 UNP_PCB_LOCK(unp); 889 if (unp->unp_addr != NULL) 890 from = (struct sockaddr *)unp->unp_addr; 891 else 892 from = &sun_noname; 893 so2 = unp2->unp_socket; 894 SOCKBUF_LOCK(&so2->so_rcv); 895 if (sbappendaddr_locked(&so2->so_rcv, from, m, control)) { 896 sorwakeup_locked(so2); 897 m = NULL; 898 control = NULL; 899 } else { 900 SOCKBUF_UNLOCK(&so2->so_rcv); 901 error = ENOBUFS; 902 } 903 if (nam != NULL) { 904 UNP_LINK_WLOCK_ASSERT(); 905 UNP_PCB_LOCK(unp2); 906 unp_disconnect(unp, unp2); 907 UNP_PCB_UNLOCK(unp2); 908 } 909 UNP_PCB_UNLOCK(unp); 910 break; 911 } 912 913 case SOCK_SEQPACKET: 914 case SOCK_STREAM: 915 if ((so->so_state & SS_ISCONNECTED) == 0) { 916 if (nam != NULL) { 917 UNP_LINK_WLOCK_ASSERT(); 918 error = unp_connect(so, nam, td); 919 if (error) 920 break; /* XXX */ 921 } else { 922 error = ENOTCONN; 923 break; 924 } 925 } 926 927 /* Lockless read. */ 928 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 929 error = EPIPE; 930 break; 931 } 932 933 /* 934 * Because connect() and send() are non-atomic in a sendto() 935 * with a target address, it's possible that the socket will 936 * have disconnected before the send() can run. In that case 937 * return the slightly counter-intuitive but otherwise 938 * correct error that the socket is not connected. 939 * 940 * Locking here must be done carefully: the linkage lock 941 * prevents interconnections between unpcbs from changing, so 942 * we can traverse from unp to unp2 without acquiring unp's 943 * lock. Socket buffer locks follow unpcb locks, so we can 944 * acquire both remote and lock socket buffer locks. 945 */ 946 unp2 = unp->unp_conn; 947 if (unp2 == NULL) { 948 error = ENOTCONN; 949 break; 950 } 951 so2 = unp2->unp_socket; 952 UNP_PCB_LOCK(unp2); 953 SOCKBUF_LOCK(&so2->so_rcv); 954 if (unp2->unp_flags & UNP_WANTCRED) { 955 /* 956 * Credentials are passed only once on SOCK_STREAM 957 * and SOCK_SEQPACKET. 958 */ 959 unp2->unp_flags &= ~UNP_WANTCRED; 960 control = unp_addsockcred(td, control); 961 } 962 /* 963 * Send to paired receive port, and then reduce send buffer 964 * hiwater marks to maintain backpressure. Wake up readers. 965 */ 966 switch (so->so_type) { 967 case SOCK_STREAM: 968 if (control != NULL) { 969 if (sbappendcontrol_locked(&so2->so_rcv, m, 970 control)) 971 control = NULL; 972 } else 973 sbappend_locked(&so2->so_rcv, m); 974 break; 975 976 case SOCK_SEQPACKET: { 977 const struct sockaddr *from; 978 979 from = &sun_noname; 980 if (sbappendaddr_locked(&so2->so_rcv, from, m, 981 control)) 982 control = NULL; 983 break; 984 } 985 } 986 987 /* 988 * XXXRW: While fine for SOCK_STREAM, this conflates maximum 989 * datagram size and back-pressure for SOCK_SEQPACKET, which 990 * can lead to undesired return of EMSGSIZE on send instead 991 * of more desirable blocking. 992 */ 993 mbcnt_delta = so2->so_rcv.sb_mbcnt - unp2->unp_mbcnt; 994 unp2->unp_mbcnt = so2->so_rcv.sb_mbcnt; 995 sbcc = so2->so_rcv.sb_cc; 996 sorwakeup_locked(so2); 997 998 SOCKBUF_LOCK(&so->so_snd); 999 if ((int)so->so_snd.sb_hiwat >= (int)(sbcc - unp2->unp_cc)) 1000 newhiwat = so->so_snd.sb_hiwat - (sbcc - unp2->unp_cc); 1001 else 1002 newhiwat = 0; 1003 (void)chgsbsize(so->so_cred->cr_uidinfo, &so->so_snd.sb_hiwat, 1004 newhiwat, RLIM_INFINITY); 1005 so->so_snd.sb_mbmax -= mbcnt_delta; 1006 SOCKBUF_UNLOCK(&so->so_snd); 1007 unp2->unp_cc = sbcc; 1008 UNP_PCB_UNLOCK(unp2); 1009 m = NULL; 1010 break; 1011 1012 default: 1013 panic("uipc_send unknown socktype"); 1014 } 1015 1016 /* 1017 * PRUS_EOF is equivalent to pru_send followed by pru_shutdown. 1018 */ 1019 if (flags & PRUS_EOF) { 1020 UNP_PCB_LOCK(unp); 1021 socantsendmore(so); 1022 unp_shutdown(unp); 1023 UNP_PCB_UNLOCK(unp); 1024 } 1025 1026 if ((nam != NULL) || (flags & PRUS_EOF)) 1027 UNP_LINK_WUNLOCK(); 1028 else 1029 UNP_LINK_RUNLOCK(); 1030 1031 if (control != NULL && error != 0) 1032 unp_dispose(control); 1033 1034 release: 1035 if (control != NULL) 1036 m_freem(control); 1037 if (m != NULL) 1038 m_freem(m); 1039 return (error); 1040 } 1041 1042 static int 1043 uipc_sense(struct socket *so, struct stat *sb) 1044 { 1045 struct unpcb *unp, *unp2; 1046 struct socket *so2; 1047 1048 unp = sotounpcb(so); 1049 KASSERT(unp != NULL, ("uipc_sense: unp == NULL")); 1050 1051 sb->st_blksize = so->so_snd.sb_hiwat; 1052 UNP_LINK_RLOCK(); 1053 UNP_PCB_LOCK(unp); 1054 unp2 = unp->unp_conn; 1055 if ((so->so_type == SOCK_STREAM || so->so_type == SOCK_SEQPACKET) && 1056 unp2 != NULL) { 1057 so2 = unp2->unp_socket; 1058 sb->st_blksize += so2->so_rcv.sb_cc; 1059 } 1060 sb->st_dev = NODEV; 1061 if (unp->unp_ino == 0) 1062 unp->unp_ino = (++unp_ino == 0) ? ++unp_ino : unp_ino; 1063 sb->st_ino = unp->unp_ino; 1064 UNP_PCB_UNLOCK(unp); 1065 UNP_LINK_RUNLOCK(); 1066 return (0); 1067 } 1068 1069 static int 1070 uipc_shutdown(struct socket *so) 1071 { 1072 struct unpcb *unp; 1073 1074 unp = sotounpcb(so); 1075 KASSERT(unp != NULL, ("uipc_shutdown: unp == NULL")); 1076 1077 UNP_LINK_WLOCK(); 1078 UNP_PCB_LOCK(unp); 1079 socantsendmore(so); 1080 unp_shutdown(unp); 1081 UNP_PCB_UNLOCK(unp); 1082 UNP_LINK_WUNLOCK(); 1083 return (0); 1084 } 1085 1086 static int 1087 uipc_sockaddr(struct socket *so, struct sockaddr **nam) 1088 { 1089 struct unpcb *unp; 1090 const struct sockaddr *sa; 1091 1092 unp = sotounpcb(so); 1093 KASSERT(unp != NULL, ("uipc_sockaddr: unp == NULL")); 1094 1095 *nam = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK); 1096 UNP_PCB_LOCK(unp); 1097 if (unp->unp_addr != NULL) 1098 sa = (struct sockaddr *) unp->unp_addr; 1099 else 1100 sa = &sun_noname; 1101 bcopy(sa, *nam, sa->sa_len); 1102 UNP_PCB_UNLOCK(unp); 1103 return (0); 1104 } 1105 1106 static struct pr_usrreqs uipc_usrreqs_dgram = { 1107 .pru_abort = uipc_abort, 1108 .pru_accept = uipc_accept, 1109 .pru_attach = uipc_attach, 1110 .pru_bind = uipc_bind, 1111 .pru_bindat = uipc_bindat, 1112 .pru_connect = uipc_connect, 1113 .pru_connectat = uipc_connectat, 1114 .pru_connect2 = uipc_connect2, 1115 .pru_detach = uipc_detach, 1116 .pru_disconnect = uipc_disconnect, 1117 .pru_listen = uipc_listen, 1118 .pru_peeraddr = uipc_peeraddr, 1119 .pru_rcvd = uipc_rcvd, 1120 .pru_send = uipc_send, 1121 .pru_sense = uipc_sense, 1122 .pru_shutdown = uipc_shutdown, 1123 .pru_sockaddr = uipc_sockaddr, 1124 .pru_soreceive = soreceive_dgram, 1125 .pru_close = uipc_close, 1126 }; 1127 1128 static struct pr_usrreqs uipc_usrreqs_seqpacket = { 1129 .pru_abort = uipc_abort, 1130 .pru_accept = uipc_accept, 1131 .pru_attach = uipc_attach, 1132 .pru_bind = uipc_bind, 1133 .pru_bindat = uipc_bindat, 1134 .pru_connect = uipc_connect, 1135 .pru_connectat = uipc_connectat, 1136 .pru_connect2 = uipc_connect2, 1137 .pru_detach = uipc_detach, 1138 .pru_disconnect = uipc_disconnect, 1139 .pru_listen = uipc_listen, 1140 .pru_peeraddr = uipc_peeraddr, 1141 .pru_rcvd = uipc_rcvd, 1142 .pru_send = uipc_send, 1143 .pru_sense = uipc_sense, 1144 .pru_shutdown = uipc_shutdown, 1145 .pru_sockaddr = uipc_sockaddr, 1146 .pru_soreceive = soreceive_generic, /* XXX: or...? */ 1147 .pru_close = uipc_close, 1148 }; 1149 1150 static struct pr_usrreqs uipc_usrreqs_stream = { 1151 .pru_abort = uipc_abort, 1152 .pru_accept = uipc_accept, 1153 .pru_attach = uipc_attach, 1154 .pru_bind = uipc_bind, 1155 .pru_bindat = uipc_bindat, 1156 .pru_connect = uipc_connect, 1157 .pru_connectat = uipc_connectat, 1158 .pru_connect2 = uipc_connect2, 1159 .pru_detach = uipc_detach, 1160 .pru_disconnect = uipc_disconnect, 1161 .pru_listen = uipc_listen, 1162 .pru_peeraddr = uipc_peeraddr, 1163 .pru_rcvd = uipc_rcvd, 1164 .pru_send = uipc_send, 1165 .pru_sense = uipc_sense, 1166 .pru_shutdown = uipc_shutdown, 1167 .pru_sockaddr = uipc_sockaddr, 1168 .pru_soreceive = soreceive_generic, 1169 .pru_close = uipc_close, 1170 }; 1171 1172 static int 1173 uipc_ctloutput(struct socket *so, struct sockopt *sopt) 1174 { 1175 struct unpcb *unp; 1176 struct xucred xu; 1177 int error, optval; 1178 1179 if (sopt->sopt_level != 0) 1180 return (EINVAL); 1181 1182 unp = sotounpcb(so); 1183 KASSERT(unp != NULL, ("uipc_ctloutput: unp == NULL")); 1184 error = 0; 1185 switch (sopt->sopt_dir) { 1186 case SOPT_GET: 1187 switch (sopt->sopt_name) { 1188 case LOCAL_PEERCRED: 1189 UNP_PCB_LOCK(unp); 1190 if (unp->unp_flags & UNP_HAVEPC) 1191 xu = unp->unp_peercred; 1192 else { 1193 if (so->so_type == SOCK_STREAM) 1194 error = ENOTCONN; 1195 else 1196 error = EINVAL; 1197 } 1198 UNP_PCB_UNLOCK(unp); 1199 if (error == 0) 1200 error = sooptcopyout(sopt, &xu, sizeof(xu)); 1201 break; 1202 1203 case LOCAL_CREDS: 1204 /* Unlocked read. */ 1205 optval = unp->unp_flags & UNP_WANTCRED ? 1 : 0; 1206 error = sooptcopyout(sopt, &optval, sizeof(optval)); 1207 break; 1208 1209 case LOCAL_CONNWAIT: 1210 /* Unlocked read. */ 1211 optval = unp->unp_flags & UNP_CONNWAIT ? 1 : 0; 1212 error = sooptcopyout(sopt, &optval, sizeof(optval)); 1213 break; 1214 1215 default: 1216 error = EOPNOTSUPP; 1217 break; 1218 } 1219 break; 1220 1221 case SOPT_SET: 1222 switch (sopt->sopt_name) { 1223 case LOCAL_CREDS: 1224 case LOCAL_CONNWAIT: 1225 error = sooptcopyin(sopt, &optval, sizeof(optval), 1226 sizeof(optval)); 1227 if (error) 1228 break; 1229 1230 #define OPTSET(bit) do { \ 1231 UNP_PCB_LOCK(unp); \ 1232 if (optval) \ 1233 unp->unp_flags |= bit; \ 1234 else \ 1235 unp->unp_flags &= ~bit; \ 1236 UNP_PCB_UNLOCK(unp); \ 1237 } while (0) 1238 1239 switch (sopt->sopt_name) { 1240 case LOCAL_CREDS: 1241 OPTSET(UNP_WANTCRED); 1242 break; 1243 1244 case LOCAL_CONNWAIT: 1245 OPTSET(UNP_CONNWAIT); 1246 break; 1247 1248 default: 1249 break; 1250 } 1251 break; 1252 #undef OPTSET 1253 default: 1254 error = ENOPROTOOPT; 1255 break; 1256 } 1257 break; 1258 1259 default: 1260 error = EOPNOTSUPP; 1261 break; 1262 } 1263 return (error); 1264 } 1265 1266 static int 1267 unp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1268 { 1269 1270 return (unp_connectat(AT_FDCWD, so, nam, td)); 1271 } 1272 1273 static int 1274 unp_connectat(int fd, struct socket *so, struct sockaddr *nam, 1275 struct thread *td) 1276 { 1277 struct sockaddr_un *soun = (struct sockaddr_un *)nam; 1278 struct vnode *vp; 1279 struct socket *so2, *so3; 1280 struct unpcb *unp, *unp2, *unp3; 1281 struct nameidata nd; 1282 char buf[SOCK_MAXADDRLEN]; 1283 struct sockaddr *sa; 1284 cap_rights_t rights; 1285 int error, len; 1286 1287 UNP_LINK_WLOCK_ASSERT(); 1288 1289 unp = sotounpcb(so); 1290 KASSERT(unp != NULL, ("unp_connect: unp == NULL")); 1291 1292 if (nam->sa_len > sizeof(struct sockaddr_un)) 1293 return (EINVAL); 1294 len = nam->sa_len - offsetof(struct sockaddr_un, sun_path); 1295 if (len <= 0) 1296 return (EINVAL); 1297 bcopy(soun->sun_path, buf, len); 1298 buf[len] = 0; 1299 1300 UNP_PCB_LOCK(unp); 1301 if (unp->unp_flags & UNP_CONNECTING) { 1302 UNP_PCB_UNLOCK(unp); 1303 return (EALREADY); 1304 } 1305 UNP_LINK_WUNLOCK(); 1306 unp->unp_flags |= UNP_CONNECTING; 1307 UNP_PCB_UNLOCK(unp); 1308 1309 sa = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK); 1310 NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF, 1311 UIO_SYSSPACE, buf, fd, cap_rights_init(&rights, CAP_CONNECTAT), td); 1312 error = namei(&nd); 1313 if (error) 1314 vp = NULL; 1315 else 1316 vp = nd.ni_vp; 1317 ASSERT_VOP_LOCKED(vp, "unp_connect"); 1318 NDFREE(&nd, NDF_ONLY_PNBUF); 1319 if (error) 1320 goto bad; 1321 1322 if (vp->v_type != VSOCK) { 1323 error = ENOTSOCK; 1324 goto bad; 1325 } 1326 #ifdef MAC 1327 error = mac_vnode_check_open(td->td_ucred, vp, VWRITE | VREAD); 1328 if (error) 1329 goto bad; 1330 #endif 1331 error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td); 1332 if (error) 1333 goto bad; 1334 1335 unp = sotounpcb(so); 1336 KASSERT(unp != NULL, ("unp_connect: unp == NULL")); 1337 1338 /* 1339 * Lock linkage lock for two reasons: make sure v_socket is stable, 1340 * and to protect simultaneous locking of multiple pcbs. 1341 */ 1342 UNP_LINK_WLOCK(); 1343 VOP_UNP_CONNECT(vp, &so2); 1344 if (so2 == NULL) { 1345 error = ECONNREFUSED; 1346 goto bad2; 1347 } 1348 if (so->so_type != so2->so_type) { 1349 error = EPROTOTYPE; 1350 goto bad2; 1351 } 1352 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 1353 if (so2->so_options & SO_ACCEPTCONN) { 1354 CURVNET_SET(so2->so_vnet); 1355 so3 = sonewconn(so2, 0); 1356 CURVNET_RESTORE(); 1357 } else 1358 so3 = NULL; 1359 if (so3 == NULL) { 1360 error = ECONNREFUSED; 1361 goto bad2; 1362 } 1363 unp = sotounpcb(so); 1364 unp2 = sotounpcb(so2); 1365 unp3 = sotounpcb(so3); 1366 UNP_PCB_LOCK(unp); 1367 UNP_PCB_LOCK(unp2); 1368 UNP_PCB_LOCK(unp3); 1369 if (unp2->unp_addr != NULL) { 1370 bcopy(unp2->unp_addr, sa, unp2->unp_addr->sun_len); 1371 unp3->unp_addr = (struct sockaddr_un *) sa; 1372 sa = NULL; 1373 } 1374 1375 /* 1376 * The connector's (client's) credentials are copied from its 1377 * process structure at the time of connect() (which is now). 1378 */ 1379 cru2x(td->td_ucred, &unp3->unp_peercred); 1380 unp3->unp_flags |= UNP_HAVEPC; 1381 1382 /* 1383 * The receiver's (server's) credentials are copied from the 1384 * unp_peercred member of socket on which the former called 1385 * listen(); uipc_listen() cached that process's credentials 1386 * at that time so we can use them now. 1387 */ 1388 KASSERT(unp2->unp_flags & UNP_HAVEPCCACHED, 1389 ("unp_connect: listener without cached peercred")); 1390 memcpy(&unp->unp_peercred, &unp2->unp_peercred, 1391 sizeof(unp->unp_peercred)); 1392 unp->unp_flags |= UNP_HAVEPC; 1393 if (unp2->unp_flags & UNP_WANTCRED) 1394 unp3->unp_flags |= UNP_WANTCRED; 1395 UNP_PCB_UNLOCK(unp3); 1396 UNP_PCB_UNLOCK(unp2); 1397 UNP_PCB_UNLOCK(unp); 1398 #ifdef MAC 1399 mac_socketpeer_set_from_socket(so, so3); 1400 mac_socketpeer_set_from_socket(so3, so); 1401 #endif 1402 1403 so2 = so3; 1404 } 1405 unp = sotounpcb(so); 1406 KASSERT(unp != NULL, ("unp_connect: unp == NULL")); 1407 unp2 = sotounpcb(so2); 1408 KASSERT(unp2 != NULL, ("unp_connect: unp2 == NULL")); 1409 UNP_PCB_LOCK(unp); 1410 UNP_PCB_LOCK(unp2); 1411 error = unp_connect2(so, so2, PRU_CONNECT); 1412 UNP_PCB_UNLOCK(unp2); 1413 UNP_PCB_UNLOCK(unp); 1414 bad2: 1415 UNP_LINK_WUNLOCK(); 1416 bad: 1417 if (vp != NULL) 1418 vput(vp); 1419 free(sa, M_SONAME); 1420 UNP_LINK_WLOCK(); 1421 UNP_PCB_LOCK(unp); 1422 unp->unp_flags &= ~UNP_CONNECTING; 1423 UNP_PCB_UNLOCK(unp); 1424 return (error); 1425 } 1426 1427 static int 1428 unp_connect2(struct socket *so, struct socket *so2, int req) 1429 { 1430 struct unpcb *unp; 1431 struct unpcb *unp2; 1432 1433 unp = sotounpcb(so); 1434 KASSERT(unp != NULL, ("unp_connect2: unp == NULL")); 1435 unp2 = sotounpcb(so2); 1436 KASSERT(unp2 != NULL, ("unp_connect2: unp2 == NULL")); 1437 1438 UNP_LINK_WLOCK_ASSERT(); 1439 UNP_PCB_LOCK_ASSERT(unp); 1440 UNP_PCB_LOCK_ASSERT(unp2); 1441 1442 if (so2->so_type != so->so_type) 1443 return (EPROTOTYPE); 1444 unp->unp_conn = unp2; 1445 1446 switch (so->so_type) { 1447 case SOCK_DGRAM: 1448 LIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_reflink); 1449 soisconnected(so); 1450 break; 1451 1452 case SOCK_STREAM: 1453 case SOCK_SEQPACKET: 1454 unp2->unp_conn = unp; 1455 if (req == PRU_CONNECT && 1456 ((unp->unp_flags | unp2->unp_flags) & UNP_CONNWAIT)) 1457 soisconnecting(so); 1458 else 1459 soisconnected(so); 1460 soisconnected(so2); 1461 break; 1462 1463 default: 1464 panic("unp_connect2"); 1465 } 1466 return (0); 1467 } 1468 1469 static void 1470 unp_disconnect(struct unpcb *unp, struct unpcb *unp2) 1471 { 1472 struct socket *so; 1473 1474 KASSERT(unp2 != NULL, ("unp_disconnect: unp2 == NULL")); 1475 1476 UNP_LINK_WLOCK_ASSERT(); 1477 UNP_PCB_LOCK_ASSERT(unp); 1478 UNP_PCB_LOCK_ASSERT(unp2); 1479 1480 unp->unp_conn = NULL; 1481 switch (unp->unp_socket->so_type) { 1482 case SOCK_DGRAM: 1483 LIST_REMOVE(unp, unp_reflink); 1484 so = unp->unp_socket; 1485 SOCK_LOCK(so); 1486 so->so_state &= ~SS_ISCONNECTED; 1487 SOCK_UNLOCK(so); 1488 break; 1489 1490 case SOCK_STREAM: 1491 case SOCK_SEQPACKET: 1492 soisdisconnected(unp->unp_socket); 1493 unp2->unp_conn = NULL; 1494 soisdisconnected(unp2->unp_socket); 1495 break; 1496 } 1497 } 1498 1499 /* 1500 * unp_pcblist() walks the global list of struct unpcb's to generate a 1501 * pointer list, bumping the refcount on each unpcb. It then copies them out 1502 * sequentially, validating the generation number on each to see if it has 1503 * been detached. All of this is necessary because copyout() may sleep on 1504 * disk I/O. 1505 */ 1506 static int 1507 unp_pcblist(SYSCTL_HANDLER_ARGS) 1508 { 1509 int error, i, n; 1510 int freeunp; 1511 struct unpcb *unp, **unp_list; 1512 unp_gen_t gencnt; 1513 struct xunpgen *xug; 1514 struct unp_head *head; 1515 struct xunpcb *xu; 1516 1517 switch ((intptr_t)arg1) { 1518 case SOCK_STREAM: 1519 head = &unp_shead; 1520 break; 1521 1522 case SOCK_DGRAM: 1523 head = &unp_dhead; 1524 break; 1525 1526 case SOCK_SEQPACKET: 1527 head = &unp_sphead; 1528 break; 1529 1530 default: 1531 panic("unp_pcblist: arg1 %d", (int)(intptr_t)arg1); 1532 } 1533 1534 /* 1535 * The process of preparing the PCB list is too time-consuming and 1536 * resource-intensive to repeat twice on every request. 1537 */ 1538 if (req->oldptr == NULL) { 1539 n = unp_count; 1540 req->oldidx = 2 * (sizeof *xug) 1541 + (n + n/8) * sizeof(struct xunpcb); 1542 return (0); 1543 } 1544 1545 if (req->newptr != NULL) 1546 return (EPERM); 1547 1548 /* 1549 * OK, now we're committed to doing something. 1550 */ 1551 xug = malloc(sizeof(*xug), M_TEMP, M_WAITOK); 1552 UNP_LIST_LOCK(); 1553 gencnt = unp_gencnt; 1554 n = unp_count; 1555 UNP_LIST_UNLOCK(); 1556 1557 xug->xug_len = sizeof *xug; 1558 xug->xug_count = n; 1559 xug->xug_gen = gencnt; 1560 xug->xug_sogen = so_gencnt; 1561 error = SYSCTL_OUT(req, xug, sizeof *xug); 1562 if (error) { 1563 free(xug, M_TEMP); 1564 return (error); 1565 } 1566 1567 unp_list = malloc(n * sizeof *unp_list, M_TEMP, M_WAITOK); 1568 1569 UNP_LIST_LOCK(); 1570 for (unp = LIST_FIRST(head), i = 0; unp && i < n; 1571 unp = LIST_NEXT(unp, unp_link)) { 1572 UNP_PCB_LOCK(unp); 1573 if (unp->unp_gencnt <= gencnt) { 1574 if (cr_cansee(req->td->td_ucred, 1575 unp->unp_socket->so_cred)) { 1576 UNP_PCB_UNLOCK(unp); 1577 continue; 1578 } 1579 unp_list[i++] = unp; 1580 unp->unp_refcount++; 1581 } 1582 UNP_PCB_UNLOCK(unp); 1583 } 1584 UNP_LIST_UNLOCK(); 1585 n = i; /* In case we lost some during malloc. */ 1586 1587 error = 0; 1588 xu = malloc(sizeof(*xu), M_TEMP, M_WAITOK | M_ZERO); 1589 for (i = 0; i < n; i++) { 1590 unp = unp_list[i]; 1591 UNP_PCB_LOCK(unp); 1592 unp->unp_refcount--; 1593 if (unp->unp_refcount != 0 && unp->unp_gencnt <= gencnt) { 1594 xu->xu_len = sizeof *xu; 1595 xu->xu_unpp = unp; 1596 /* 1597 * XXX - need more locking here to protect against 1598 * connect/disconnect races for SMP. 1599 */ 1600 if (unp->unp_addr != NULL) 1601 bcopy(unp->unp_addr, &xu->xu_addr, 1602 unp->unp_addr->sun_len); 1603 if (unp->unp_conn != NULL && 1604 unp->unp_conn->unp_addr != NULL) 1605 bcopy(unp->unp_conn->unp_addr, 1606 &xu->xu_caddr, 1607 unp->unp_conn->unp_addr->sun_len); 1608 bcopy(unp, &xu->xu_unp, sizeof *unp); 1609 sotoxsocket(unp->unp_socket, &xu->xu_socket); 1610 UNP_PCB_UNLOCK(unp); 1611 error = SYSCTL_OUT(req, xu, sizeof *xu); 1612 } else { 1613 freeunp = (unp->unp_refcount == 0); 1614 UNP_PCB_UNLOCK(unp); 1615 if (freeunp) { 1616 UNP_PCB_LOCK_DESTROY(unp); 1617 uma_zfree(unp_zone, unp); 1618 } 1619 } 1620 } 1621 free(xu, M_TEMP); 1622 if (!error) { 1623 /* 1624 * Give the user an updated idea of our state. If the 1625 * generation differs from what we told her before, she knows 1626 * that something happened while we were processing this 1627 * request, and it might be necessary to retry. 1628 */ 1629 xug->xug_gen = unp_gencnt; 1630 xug->xug_sogen = so_gencnt; 1631 xug->xug_count = unp_count; 1632 error = SYSCTL_OUT(req, xug, sizeof *xug); 1633 } 1634 free(unp_list, M_TEMP); 1635 free(xug, M_TEMP); 1636 return (error); 1637 } 1638 1639 SYSCTL_PROC(_net_local_dgram, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD, 1640 (void *)(intptr_t)SOCK_DGRAM, 0, unp_pcblist, "S,xunpcb", 1641 "List of active local datagram sockets"); 1642 SYSCTL_PROC(_net_local_stream, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD, 1643 (void *)(intptr_t)SOCK_STREAM, 0, unp_pcblist, "S,xunpcb", 1644 "List of active local stream sockets"); 1645 SYSCTL_PROC(_net_local_seqpacket, OID_AUTO, pcblist, 1646 CTLTYPE_OPAQUE | CTLFLAG_RD, 1647 (void *)(intptr_t)SOCK_SEQPACKET, 0, unp_pcblist, "S,xunpcb", 1648 "List of active local seqpacket sockets"); 1649 1650 static void 1651 unp_shutdown(struct unpcb *unp) 1652 { 1653 struct unpcb *unp2; 1654 struct socket *so; 1655 1656 UNP_LINK_WLOCK_ASSERT(); 1657 UNP_PCB_LOCK_ASSERT(unp); 1658 1659 unp2 = unp->unp_conn; 1660 if ((unp->unp_socket->so_type == SOCK_STREAM || 1661 (unp->unp_socket->so_type == SOCK_SEQPACKET)) && unp2 != NULL) { 1662 so = unp2->unp_socket; 1663 if (so != NULL) 1664 socantrcvmore(so); 1665 } 1666 } 1667 1668 static void 1669 unp_drop(struct unpcb *unp, int errno) 1670 { 1671 struct socket *so = unp->unp_socket; 1672 struct unpcb *unp2; 1673 1674 UNP_LINK_WLOCK_ASSERT(); 1675 UNP_PCB_LOCK_ASSERT(unp); 1676 1677 so->so_error = errno; 1678 unp2 = unp->unp_conn; 1679 if (unp2 == NULL) 1680 return; 1681 UNP_PCB_LOCK(unp2); 1682 unp_disconnect(unp, unp2); 1683 UNP_PCB_UNLOCK(unp2); 1684 } 1685 1686 static void 1687 unp_freerights(struct filedescent **fdep, int fdcount) 1688 { 1689 struct file *fp; 1690 int i; 1691 1692 KASSERT(fdcount > 0, ("%s: fdcount %d", __func__, fdcount)); 1693 1694 for (i = 0; i < fdcount; i++) { 1695 fp = fdep[i]->fde_file; 1696 filecaps_free(&fdep[i]->fde_caps); 1697 unp_discard(fp); 1698 } 1699 free(fdep[0], M_FILECAPS); 1700 } 1701 1702 static int 1703 unp_externalize(struct mbuf *control, struct mbuf **controlp, int flags) 1704 { 1705 struct thread *td = curthread; /* XXX */ 1706 struct cmsghdr *cm = mtod(control, struct cmsghdr *); 1707 int i; 1708 int *fdp; 1709 struct filedesc *fdesc = td->td_proc->p_fd; 1710 struct filedescent *fde, **fdep; 1711 void *data; 1712 socklen_t clen = control->m_len, datalen; 1713 int error, newfds; 1714 u_int newlen; 1715 1716 UNP_LINK_UNLOCK_ASSERT(); 1717 1718 error = 0; 1719 if (controlp != NULL) /* controlp == NULL => free control messages */ 1720 *controlp = NULL; 1721 while (cm != NULL) { 1722 if (sizeof(*cm) > clen || cm->cmsg_len > clen) { 1723 error = EINVAL; 1724 break; 1725 } 1726 data = CMSG_DATA(cm); 1727 datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data; 1728 if (cm->cmsg_level == SOL_SOCKET 1729 && cm->cmsg_type == SCM_RIGHTS) { 1730 newfds = datalen / sizeof(*fdep); 1731 if (newfds == 0) 1732 goto next; 1733 fdep = data; 1734 1735 /* If we're not outputting the descriptors free them. */ 1736 if (error || controlp == NULL) { 1737 unp_freerights(fdep, newfds); 1738 goto next; 1739 } 1740 FILEDESC_XLOCK(fdesc); 1741 1742 /* 1743 * Now change each pointer to an fd in the global 1744 * table to an integer that is the index to the local 1745 * fd table entry that we set up to point to the 1746 * global one we are transferring. 1747 */ 1748 newlen = newfds * sizeof(int); 1749 *controlp = sbcreatecontrol(NULL, newlen, 1750 SCM_RIGHTS, SOL_SOCKET); 1751 if (*controlp == NULL) { 1752 FILEDESC_XUNLOCK(fdesc); 1753 error = E2BIG; 1754 unp_freerights(fdep, newfds); 1755 goto next; 1756 } 1757 1758 fdp = (int *) 1759 CMSG_DATA(mtod(*controlp, struct cmsghdr *)); 1760 if (fdallocn(td, 0, fdp, newfds) != 0) { 1761 FILEDESC_XUNLOCK(td->td_proc->p_fd); 1762 error = EMSGSIZE; 1763 unp_freerights(fdep, newfds); 1764 m_freem(*controlp); 1765 *controlp = NULL; 1766 goto next; 1767 } 1768 for (i = 0; i < newfds; i++, fdp++) { 1769 fde = &fdesc->fd_ofiles[*fdp]; 1770 fde->fde_file = fdep[i]->fde_file; 1771 filecaps_move(&fdep[i]->fde_caps, 1772 &fde->fde_caps); 1773 if ((flags & MSG_CMSG_CLOEXEC) != 0) 1774 fde->fde_flags |= UF_EXCLOSE; 1775 unp_externalize_fp(fde->fde_file); 1776 } 1777 FILEDESC_XUNLOCK(fdesc); 1778 free(fdep[0], M_FILECAPS); 1779 } else { 1780 /* We can just copy anything else across. */ 1781 if (error || controlp == NULL) 1782 goto next; 1783 *controlp = sbcreatecontrol(NULL, datalen, 1784 cm->cmsg_type, cm->cmsg_level); 1785 if (*controlp == NULL) { 1786 error = ENOBUFS; 1787 goto next; 1788 } 1789 bcopy(data, 1790 CMSG_DATA(mtod(*controlp, struct cmsghdr *)), 1791 datalen); 1792 } 1793 controlp = &(*controlp)->m_next; 1794 1795 next: 1796 if (CMSG_SPACE(datalen) < clen) { 1797 clen -= CMSG_SPACE(datalen); 1798 cm = (struct cmsghdr *) 1799 ((caddr_t)cm + CMSG_SPACE(datalen)); 1800 } else { 1801 clen = 0; 1802 cm = NULL; 1803 } 1804 } 1805 1806 m_freem(control); 1807 return (error); 1808 } 1809 1810 static void 1811 unp_zone_change(void *tag) 1812 { 1813 1814 uma_zone_set_max(unp_zone, maxsockets); 1815 } 1816 1817 static void 1818 unp_init(void) 1819 { 1820 1821 #ifdef VIMAGE 1822 if (!IS_DEFAULT_VNET(curvnet)) 1823 return; 1824 #endif 1825 unp_zone = uma_zcreate("unpcb", sizeof(struct unpcb), NULL, NULL, 1826 NULL, NULL, UMA_ALIGN_PTR, 0); 1827 if (unp_zone == NULL) 1828 panic("unp_init"); 1829 uma_zone_set_max(unp_zone, maxsockets); 1830 uma_zone_set_warning(unp_zone, "kern.ipc.maxsockets limit reached"); 1831 EVENTHANDLER_REGISTER(maxsockets_change, unp_zone_change, 1832 NULL, EVENTHANDLER_PRI_ANY); 1833 LIST_INIT(&unp_dhead); 1834 LIST_INIT(&unp_shead); 1835 LIST_INIT(&unp_sphead); 1836 SLIST_INIT(&unp_defers); 1837 TIMEOUT_TASK_INIT(taskqueue_thread, &unp_gc_task, 0, unp_gc, NULL); 1838 TASK_INIT(&unp_defer_task, 0, unp_process_defers, NULL); 1839 UNP_LINK_LOCK_INIT(); 1840 UNP_LIST_LOCK_INIT(); 1841 UNP_DEFERRED_LOCK_INIT(); 1842 } 1843 1844 static int 1845 unp_internalize(struct mbuf **controlp, struct thread *td) 1846 { 1847 struct mbuf *control = *controlp; 1848 struct proc *p = td->td_proc; 1849 struct filedesc *fdesc = p->p_fd; 1850 struct bintime *bt; 1851 struct cmsghdr *cm = mtod(control, struct cmsghdr *); 1852 struct cmsgcred *cmcred; 1853 struct filedescent *fde, **fdep, *fdev; 1854 struct file *fp; 1855 struct timeval *tv; 1856 int i, fd, *fdp; 1857 void *data; 1858 socklen_t clen = control->m_len, datalen; 1859 int error, oldfds; 1860 u_int newlen; 1861 1862 UNP_LINK_UNLOCK_ASSERT(); 1863 1864 error = 0; 1865 *controlp = NULL; 1866 while (cm != NULL) { 1867 if (sizeof(*cm) > clen || cm->cmsg_level != SOL_SOCKET 1868 || cm->cmsg_len > clen) { 1869 error = EINVAL; 1870 goto out; 1871 } 1872 data = CMSG_DATA(cm); 1873 datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data; 1874 1875 switch (cm->cmsg_type) { 1876 /* 1877 * Fill in credential information. 1878 */ 1879 case SCM_CREDS: 1880 *controlp = sbcreatecontrol(NULL, sizeof(*cmcred), 1881 SCM_CREDS, SOL_SOCKET); 1882 if (*controlp == NULL) { 1883 error = ENOBUFS; 1884 goto out; 1885 } 1886 cmcred = (struct cmsgcred *) 1887 CMSG_DATA(mtod(*controlp, struct cmsghdr *)); 1888 cmcred->cmcred_pid = p->p_pid; 1889 cmcred->cmcred_uid = td->td_ucred->cr_ruid; 1890 cmcred->cmcred_gid = td->td_ucred->cr_rgid; 1891 cmcred->cmcred_euid = td->td_ucred->cr_uid; 1892 cmcred->cmcred_ngroups = MIN(td->td_ucred->cr_ngroups, 1893 CMGROUP_MAX); 1894 for (i = 0; i < cmcred->cmcred_ngroups; i++) 1895 cmcred->cmcred_groups[i] = 1896 td->td_ucred->cr_groups[i]; 1897 break; 1898 1899 case SCM_RIGHTS: 1900 oldfds = datalen / sizeof (int); 1901 if (oldfds == 0) 1902 break; 1903 /* 1904 * Check that all the FDs passed in refer to legal 1905 * files. If not, reject the entire operation. 1906 */ 1907 fdp = data; 1908 FILEDESC_SLOCK(fdesc); 1909 for (i = 0; i < oldfds; i++) { 1910 fd = *fdp++; 1911 if (fget_locked(fdesc, fd) == NULL) { 1912 FILEDESC_SUNLOCK(fdesc); 1913 error = EBADF; 1914 goto out; 1915 } 1916 fp = fdesc->fd_ofiles[fd].fde_file; 1917 if (!(fp->f_ops->fo_flags & DFLAG_PASSABLE)) { 1918 FILEDESC_SUNLOCK(fdesc); 1919 error = EOPNOTSUPP; 1920 goto out; 1921 } 1922 1923 } 1924 1925 /* 1926 * Now replace the integer FDs with pointers to the 1927 * file structure and capability rights. 1928 */ 1929 newlen = oldfds * sizeof(fdep[0]); 1930 *controlp = sbcreatecontrol(NULL, newlen, 1931 SCM_RIGHTS, SOL_SOCKET); 1932 if (*controlp == NULL) { 1933 FILEDESC_SUNLOCK(fdesc); 1934 error = E2BIG; 1935 goto out; 1936 } 1937 fdp = data; 1938 fdep = (struct filedescent **) 1939 CMSG_DATA(mtod(*controlp, struct cmsghdr *)); 1940 fdev = malloc(sizeof(*fdev) * oldfds, M_FILECAPS, 1941 M_WAITOK); 1942 for (i = 0; i < oldfds; i++, fdev++, fdp++) { 1943 fde = &fdesc->fd_ofiles[*fdp]; 1944 fdep[i] = fdev; 1945 fdep[i]->fde_file = fde->fde_file; 1946 filecaps_copy(&fde->fde_caps, 1947 &fdep[i]->fde_caps); 1948 unp_internalize_fp(fdep[i]->fde_file); 1949 } 1950 FILEDESC_SUNLOCK(fdesc); 1951 break; 1952 1953 case SCM_TIMESTAMP: 1954 *controlp = sbcreatecontrol(NULL, sizeof(*tv), 1955 SCM_TIMESTAMP, SOL_SOCKET); 1956 if (*controlp == NULL) { 1957 error = ENOBUFS; 1958 goto out; 1959 } 1960 tv = (struct timeval *) 1961 CMSG_DATA(mtod(*controlp, struct cmsghdr *)); 1962 microtime(tv); 1963 break; 1964 1965 case SCM_BINTIME: 1966 *controlp = sbcreatecontrol(NULL, sizeof(*bt), 1967 SCM_BINTIME, SOL_SOCKET); 1968 if (*controlp == NULL) { 1969 error = ENOBUFS; 1970 goto out; 1971 } 1972 bt = (struct bintime *) 1973 CMSG_DATA(mtod(*controlp, struct cmsghdr *)); 1974 bintime(bt); 1975 break; 1976 1977 default: 1978 error = EINVAL; 1979 goto out; 1980 } 1981 1982 controlp = &(*controlp)->m_next; 1983 if (CMSG_SPACE(datalen) < clen) { 1984 clen -= CMSG_SPACE(datalen); 1985 cm = (struct cmsghdr *) 1986 ((caddr_t)cm + CMSG_SPACE(datalen)); 1987 } else { 1988 clen = 0; 1989 cm = NULL; 1990 } 1991 } 1992 1993 out: 1994 m_freem(control); 1995 return (error); 1996 } 1997 1998 static struct mbuf * 1999 unp_addsockcred(struct thread *td, struct mbuf *control) 2000 { 2001 struct mbuf *m, *n, *n_prev; 2002 struct sockcred *sc; 2003 const struct cmsghdr *cm; 2004 int ngroups; 2005 int i; 2006 2007 ngroups = MIN(td->td_ucred->cr_ngroups, CMGROUP_MAX); 2008 m = sbcreatecontrol(NULL, SOCKCREDSIZE(ngroups), SCM_CREDS, SOL_SOCKET); 2009 if (m == NULL) 2010 return (control); 2011 2012 sc = (struct sockcred *) CMSG_DATA(mtod(m, struct cmsghdr *)); 2013 sc->sc_uid = td->td_ucred->cr_ruid; 2014 sc->sc_euid = td->td_ucred->cr_uid; 2015 sc->sc_gid = td->td_ucred->cr_rgid; 2016 sc->sc_egid = td->td_ucred->cr_gid; 2017 sc->sc_ngroups = ngroups; 2018 for (i = 0; i < sc->sc_ngroups; i++) 2019 sc->sc_groups[i] = td->td_ucred->cr_groups[i]; 2020 2021 /* 2022 * Unlink SCM_CREDS control messages (struct cmsgcred), since just 2023 * created SCM_CREDS control message (struct sockcred) has another 2024 * format. 2025 */ 2026 if (control != NULL) 2027 for (n = control, n_prev = NULL; n != NULL;) { 2028 cm = mtod(n, struct cmsghdr *); 2029 if (cm->cmsg_level == SOL_SOCKET && 2030 cm->cmsg_type == SCM_CREDS) { 2031 if (n_prev == NULL) 2032 control = n->m_next; 2033 else 2034 n_prev->m_next = n->m_next; 2035 n = m_free(n); 2036 } else { 2037 n_prev = n; 2038 n = n->m_next; 2039 } 2040 } 2041 2042 /* Prepend it to the head. */ 2043 m->m_next = control; 2044 return (m); 2045 } 2046 2047 static struct unpcb * 2048 fptounp(struct file *fp) 2049 { 2050 struct socket *so; 2051 2052 if (fp->f_type != DTYPE_SOCKET) 2053 return (NULL); 2054 if ((so = fp->f_data) == NULL) 2055 return (NULL); 2056 if (so->so_proto->pr_domain != &localdomain) 2057 return (NULL); 2058 return sotounpcb(so); 2059 } 2060 2061 static void 2062 unp_discard(struct file *fp) 2063 { 2064 struct unp_defer *dr; 2065 2066 if (unp_externalize_fp(fp)) { 2067 dr = malloc(sizeof(*dr), M_TEMP, M_WAITOK); 2068 dr->ud_fp = fp; 2069 UNP_DEFERRED_LOCK(); 2070 SLIST_INSERT_HEAD(&unp_defers, dr, ud_link); 2071 UNP_DEFERRED_UNLOCK(); 2072 atomic_add_int(&unp_defers_count, 1); 2073 taskqueue_enqueue(taskqueue_thread, &unp_defer_task); 2074 } else 2075 (void) closef(fp, (struct thread *)NULL); 2076 } 2077 2078 static void 2079 unp_process_defers(void *arg __unused, int pending) 2080 { 2081 struct unp_defer *dr; 2082 SLIST_HEAD(, unp_defer) drl; 2083 int count; 2084 2085 SLIST_INIT(&drl); 2086 for (;;) { 2087 UNP_DEFERRED_LOCK(); 2088 if (SLIST_FIRST(&unp_defers) == NULL) { 2089 UNP_DEFERRED_UNLOCK(); 2090 break; 2091 } 2092 SLIST_SWAP(&unp_defers, &drl, unp_defer); 2093 UNP_DEFERRED_UNLOCK(); 2094 count = 0; 2095 while ((dr = SLIST_FIRST(&drl)) != NULL) { 2096 SLIST_REMOVE_HEAD(&drl, ud_link); 2097 closef(dr->ud_fp, NULL); 2098 free(dr, M_TEMP); 2099 count++; 2100 } 2101 atomic_add_int(&unp_defers_count, -count); 2102 } 2103 } 2104 2105 static void 2106 unp_internalize_fp(struct file *fp) 2107 { 2108 struct unpcb *unp; 2109 2110 UNP_LINK_WLOCK(); 2111 if ((unp = fptounp(fp)) != NULL) { 2112 unp->unp_file = fp; 2113 unp->unp_msgcount++; 2114 } 2115 fhold(fp); 2116 unp_rights++; 2117 UNP_LINK_WUNLOCK(); 2118 } 2119 2120 static int 2121 unp_externalize_fp(struct file *fp) 2122 { 2123 struct unpcb *unp; 2124 int ret; 2125 2126 UNP_LINK_WLOCK(); 2127 if ((unp = fptounp(fp)) != NULL) { 2128 unp->unp_msgcount--; 2129 ret = 1; 2130 } else 2131 ret = 0; 2132 unp_rights--; 2133 UNP_LINK_WUNLOCK(); 2134 return (ret); 2135 } 2136 2137 /* 2138 * unp_defer indicates whether additional work has been defered for a future 2139 * pass through unp_gc(). It is thread local and does not require explicit 2140 * synchronization. 2141 */ 2142 static int unp_marked; 2143 static int unp_unreachable; 2144 2145 static void 2146 unp_accessable(struct filedescent **fdep, int fdcount) 2147 { 2148 struct unpcb *unp; 2149 struct file *fp; 2150 int i; 2151 2152 for (i = 0; i < fdcount; i++) { 2153 fp = fdep[i]->fde_file; 2154 if ((unp = fptounp(fp)) == NULL) 2155 continue; 2156 if (unp->unp_gcflag & UNPGC_REF) 2157 continue; 2158 unp->unp_gcflag &= ~UNPGC_DEAD; 2159 unp->unp_gcflag |= UNPGC_REF; 2160 unp_marked++; 2161 } 2162 } 2163 2164 static void 2165 unp_gc_process(struct unpcb *unp) 2166 { 2167 struct socket *soa; 2168 struct socket *so; 2169 struct file *fp; 2170 2171 /* Already processed. */ 2172 if (unp->unp_gcflag & UNPGC_SCANNED) 2173 return; 2174 fp = unp->unp_file; 2175 2176 /* 2177 * Check for a socket potentially in a cycle. It must be in a 2178 * queue as indicated by msgcount, and this must equal the file 2179 * reference count. Note that when msgcount is 0 the file is NULL. 2180 */ 2181 if ((unp->unp_gcflag & UNPGC_REF) == 0 && fp && 2182 unp->unp_msgcount != 0 && fp->f_count == unp->unp_msgcount) { 2183 unp->unp_gcflag |= UNPGC_DEAD; 2184 unp_unreachable++; 2185 return; 2186 } 2187 2188 /* 2189 * Mark all sockets we reference with RIGHTS. 2190 */ 2191 so = unp->unp_socket; 2192 SOCKBUF_LOCK(&so->so_rcv); 2193 unp_scan(so->so_rcv.sb_mb, unp_accessable); 2194 SOCKBUF_UNLOCK(&so->so_rcv); 2195 2196 /* 2197 * Mark all sockets in our accept queue. 2198 */ 2199 ACCEPT_LOCK(); 2200 TAILQ_FOREACH(soa, &so->so_comp, so_list) { 2201 SOCKBUF_LOCK(&soa->so_rcv); 2202 unp_scan(soa->so_rcv.sb_mb, unp_accessable); 2203 SOCKBUF_UNLOCK(&soa->so_rcv); 2204 } 2205 ACCEPT_UNLOCK(); 2206 unp->unp_gcflag |= UNPGC_SCANNED; 2207 } 2208 2209 static int unp_recycled; 2210 SYSCTL_INT(_net_local, OID_AUTO, recycled, CTLFLAG_RD, &unp_recycled, 0, 2211 "Number of unreachable sockets claimed by the garbage collector."); 2212 2213 static int unp_taskcount; 2214 SYSCTL_INT(_net_local, OID_AUTO, taskcount, CTLFLAG_RD, &unp_taskcount, 0, 2215 "Number of times the garbage collector has run."); 2216 2217 static void 2218 unp_gc(__unused void *arg, int pending) 2219 { 2220 struct unp_head *heads[] = { &unp_dhead, &unp_shead, &unp_sphead, 2221 NULL }; 2222 struct unp_head **head; 2223 struct file *f, **unref; 2224 struct unpcb *unp; 2225 int i, total; 2226 2227 unp_taskcount++; 2228 UNP_LIST_LOCK(); 2229 /* 2230 * First clear all gc flags from previous runs. 2231 */ 2232 for (head = heads; *head != NULL; head++) 2233 LIST_FOREACH(unp, *head, unp_link) 2234 unp->unp_gcflag = 0; 2235 2236 /* 2237 * Scan marking all reachable sockets with UNPGC_REF. Once a socket 2238 * is reachable all of the sockets it references are reachable. 2239 * Stop the scan once we do a complete loop without discovering 2240 * a new reachable socket. 2241 */ 2242 do { 2243 unp_unreachable = 0; 2244 unp_marked = 0; 2245 for (head = heads; *head != NULL; head++) 2246 LIST_FOREACH(unp, *head, unp_link) 2247 unp_gc_process(unp); 2248 } while (unp_marked); 2249 UNP_LIST_UNLOCK(); 2250 if (unp_unreachable == 0) 2251 return; 2252 2253 /* 2254 * Allocate space for a local list of dead unpcbs. 2255 */ 2256 unref = malloc(unp_unreachable * sizeof(struct file *), 2257 M_TEMP, M_WAITOK); 2258 2259 /* 2260 * Iterate looking for sockets which have been specifically marked 2261 * as as unreachable and store them locally. 2262 */ 2263 UNP_LINK_RLOCK(); 2264 UNP_LIST_LOCK(); 2265 for (total = 0, head = heads; *head != NULL; head++) 2266 LIST_FOREACH(unp, *head, unp_link) 2267 if ((unp->unp_gcflag & UNPGC_DEAD) != 0) { 2268 f = unp->unp_file; 2269 if (unp->unp_msgcount == 0 || f == NULL || 2270 f->f_count != unp->unp_msgcount) 2271 continue; 2272 unref[total++] = f; 2273 fhold(f); 2274 KASSERT(total <= unp_unreachable, 2275 ("unp_gc: incorrect unreachable count.")); 2276 } 2277 UNP_LIST_UNLOCK(); 2278 UNP_LINK_RUNLOCK(); 2279 2280 /* 2281 * Now flush all sockets, free'ing rights. This will free the 2282 * struct files associated with these sockets but leave each socket 2283 * with one remaining ref. 2284 */ 2285 for (i = 0; i < total; i++) { 2286 struct socket *so; 2287 2288 so = unref[i]->f_data; 2289 CURVNET_SET(so->so_vnet); 2290 sorflush(so); 2291 CURVNET_RESTORE(); 2292 } 2293 2294 /* 2295 * And finally release the sockets so they can be reclaimed. 2296 */ 2297 for (i = 0; i < total; i++) 2298 fdrop(unref[i], NULL); 2299 unp_recycled += total; 2300 free(unref, M_TEMP); 2301 } 2302 2303 static void 2304 unp_dispose(struct mbuf *m) 2305 { 2306 2307 if (m) 2308 unp_scan(m, unp_freerights); 2309 } 2310 2311 static void 2312 unp_scan(struct mbuf *m0, void (*op)(struct filedescent **, int)) 2313 { 2314 struct mbuf *m; 2315 struct cmsghdr *cm; 2316 void *data; 2317 socklen_t clen, datalen; 2318 2319 while (m0 != NULL) { 2320 for (m = m0; m; m = m->m_next) { 2321 if (m->m_type != MT_CONTROL) 2322 continue; 2323 2324 cm = mtod(m, struct cmsghdr *); 2325 clen = m->m_len; 2326 2327 while (cm != NULL) { 2328 if (sizeof(*cm) > clen || cm->cmsg_len > clen) 2329 break; 2330 2331 data = CMSG_DATA(cm); 2332 datalen = (caddr_t)cm + cm->cmsg_len 2333 - (caddr_t)data; 2334 2335 if (cm->cmsg_level == SOL_SOCKET && 2336 cm->cmsg_type == SCM_RIGHTS) { 2337 (*op)(data, datalen / 2338 sizeof(struct filedescent *)); 2339 } 2340 2341 if (CMSG_SPACE(datalen) < clen) { 2342 clen -= CMSG_SPACE(datalen); 2343 cm = (struct cmsghdr *) 2344 ((caddr_t)cm + CMSG_SPACE(datalen)); 2345 } else { 2346 clen = 0; 2347 cm = NULL; 2348 } 2349 } 2350 } 2351 m0 = m0->m_act; 2352 } 2353 } 2354 2355 /* 2356 * A helper function called by VFS before socket-type vnode reclamation. 2357 * For an active vnode it clears unp_vnode pointer and decrements unp_vnode 2358 * use count. 2359 */ 2360 void 2361 vfs_unp_reclaim(struct vnode *vp) 2362 { 2363 struct socket *so; 2364 struct unpcb *unp; 2365 int active; 2366 2367 ASSERT_VOP_ELOCKED(vp, "vfs_unp_reclaim"); 2368 KASSERT(vp->v_type == VSOCK, 2369 ("vfs_unp_reclaim: vp->v_type != VSOCK")); 2370 2371 active = 0; 2372 UNP_LINK_WLOCK(); 2373 VOP_UNP_CONNECT(vp, &so); 2374 if (so == NULL) 2375 goto done; 2376 unp = sotounpcb(so); 2377 if (unp == NULL) 2378 goto done; 2379 UNP_PCB_LOCK(unp); 2380 if (unp->unp_vnode == vp) { 2381 VOP_UNP_DETACH(vp); 2382 unp->unp_vnode = NULL; 2383 active = 1; 2384 } 2385 UNP_PCB_UNLOCK(unp); 2386 done: 2387 UNP_LINK_WUNLOCK(); 2388 if (active) 2389 vunref(vp); 2390 } 2391 2392 #ifdef DDB 2393 static void 2394 db_print_indent(int indent) 2395 { 2396 int i; 2397 2398 for (i = 0; i < indent; i++) 2399 db_printf(" "); 2400 } 2401 2402 static void 2403 db_print_unpflags(int unp_flags) 2404 { 2405 int comma; 2406 2407 comma = 0; 2408 if (unp_flags & UNP_HAVEPC) { 2409 db_printf("%sUNP_HAVEPC", comma ? ", " : ""); 2410 comma = 1; 2411 } 2412 if (unp_flags & UNP_HAVEPCCACHED) { 2413 db_printf("%sUNP_HAVEPCCACHED", comma ? ", " : ""); 2414 comma = 1; 2415 } 2416 if (unp_flags & UNP_WANTCRED) { 2417 db_printf("%sUNP_WANTCRED", comma ? ", " : ""); 2418 comma = 1; 2419 } 2420 if (unp_flags & UNP_CONNWAIT) { 2421 db_printf("%sUNP_CONNWAIT", comma ? ", " : ""); 2422 comma = 1; 2423 } 2424 if (unp_flags & UNP_CONNECTING) { 2425 db_printf("%sUNP_CONNECTING", comma ? ", " : ""); 2426 comma = 1; 2427 } 2428 if (unp_flags & UNP_BINDING) { 2429 db_printf("%sUNP_BINDING", comma ? ", " : ""); 2430 comma = 1; 2431 } 2432 } 2433 2434 static void 2435 db_print_xucred(int indent, struct xucred *xu) 2436 { 2437 int comma, i; 2438 2439 db_print_indent(indent); 2440 db_printf("cr_version: %u cr_uid: %u cr_ngroups: %d\n", 2441 xu->cr_version, xu->cr_uid, xu->cr_ngroups); 2442 db_print_indent(indent); 2443 db_printf("cr_groups: "); 2444 comma = 0; 2445 for (i = 0; i < xu->cr_ngroups; i++) { 2446 db_printf("%s%u", comma ? ", " : "", xu->cr_groups[i]); 2447 comma = 1; 2448 } 2449 db_printf("\n"); 2450 } 2451 2452 static void 2453 db_print_unprefs(int indent, struct unp_head *uh) 2454 { 2455 struct unpcb *unp; 2456 int counter; 2457 2458 counter = 0; 2459 LIST_FOREACH(unp, uh, unp_reflink) { 2460 if (counter % 4 == 0) 2461 db_print_indent(indent); 2462 db_printf("%p ", unp); 2463 if (counter % 4 == 3) 2464 db_printf("\n"); 2465 counter++; 2466 } 2467 if (counter != 0 && counter % 4 != 0) 2468 db_printf("\n"); 2469 } 2470 2471 DB_SHOW_COMMAND(unpcb, db_show_unpcb) 2472 { 2473 struct unpcb *unp; 2474 2475 if (!have_addr) { 2476 db_printf("usage: show unpcb <addr>\n"); 2477 return; 2478 } 2479 unp = (struct unpcb *)addr; 2480 2481 db_printf("unp_socket: %p unp_vnode: %p\n", unp->unp_socket, 2482 unp->unp_vnode); 2483 2484 db_printf("unp_ino: %ju unp_conn: %p\n", (uintmax_t)unp->unp_ino, 2485 unp->unp_conn); 2486 2487 db_printf("unp_refs:\n"); 2488 db_print_unprefs(2, &unp->unp_refs); 2489 2490 /* XXXRW: Would be nice to print the full address, if any. */ 2491 db_printf("unp_addr: %p\n", unp->unp_addr); 2492 2493 db_printf("unp_cc: %d unp_mbcnt: %d unp_gencnt: %llu\n", 2494 unp->unp_cc, unp->unp_mbcnt, 2495 (unsigned long long)unp->unp_gencnt); 2496 2497 db_printf("unp_flags: %x (", unp->unp_flags); 2498 db_print_unpflags(unp->unp_flags); 2499 db_printf(")\n"); 2500 2501 db_printf("unp_peercred:\n"); 2502 db_print_xucred(2, &unp->unp_peercred); 2503 2504 db_printf("unp_refcount: %u\n", unp->unp_refcount); 2505 } 2506 #endif
Cache object: a49c5a3dc43068474982ce4f4d2bf750
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