1 /*- 2 * Copyright (c) 2001 Dag-Erling Co�dan Sm�rgrav 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_pseudofs.h" 33 34 #include <sys/param.h> 35 #include <sys/kernel.h> 36 #include <sys/systm.h> 37 #include <sys/ctype.h> 38 #include <sys/dirent.h> 39 #include <sys/fcntl.h> 40 #include <sys/limits.h> 41 #include <sys/lock.h> 42 #include <sys/malloc.h> 43 #include <sys/mount.h> 44 #include <sys/mutex.h> 45 #include <sys/namei.h> 46 #include <sys/proc.h> 47 #include <sys/sbuf.h> 48 #include <sys/sx.h> 49 #include <sys/sysctl.h> 50 #include <sys/vnode.h> 51 52 #include <fs/pseudofs/pseudofs.h> 53 #include <fs/pseudofs/pseudofs_internal.h> 54 55 #define KASSERT_PN_IS_DIR(pn) \ 56 KASSERT((pn)->pn_type == pfstype_root || \ 57 (pn)->pn_type == pfstype_dir || \ 58 (pn)->pn_type == pfstype_procdir, \ 59 ("%s(): VDIR vnode refers to non-directory pfs_node", __func__)) 60 61 #define KASSERT_PN_IS_FILE(pn) \ 62 KASSERT((pn)->pn_type == pfstype_file, \ 63 ("%s(): VREG vnode refers to non-file pfs_node", __func__)) 64 65 #define KASSERT_PN_IS_LINK(pn) \ 66 KASSERT((pn)->pn_type == pfstype_symlink, \ 67 ("%s(): VLNK vnode refers to non-link pfs_node", __func__)) 68 69 /* 70 * Returns the fileno, adjusted for target pid 71 */ 72 static uint32_t 73 pn_fileno(struct pfs_node *pn, pid_t pid) 74 { 75 76 KASSERT(pn->pn_fileno > 0, 77 ("%s(): no fileno allocated", __func__)); 78 if (pid != NO_PID) 79 return (pn->pn_fileno * NO_PID + pid); 80 return (pn->pn_fileno); 81 } 82 83 /* 84 * Returns non-zero if given file is visible to given thread. 85 */ 86 static int 87 pfs_visible_proc(struct thread *td, struct pfs_node *pn, struct proc *proc) 88 { 89 int visible; 90 91 if (proc == NULL) 92 return (0); 93 94 PROC_LOCK_ASSERT(proc, MA_OWNED); 95 96 visible = ((proc->p_flag & P_WEXIT) == 0); 97 if (visible) 98 visible = (p_cansee(td, proc) == 0); 99 if (visible && pn->pn_vis != NULL) 100 visible = pn_vis(td, proc, pn); 101 if (!visible) 102 return (0); 103 return (1); 104 } 105 106 static int 107 pfs_visible(struct thread *td, struct pfs_node *pn, pid_t pid, struct proc **p) 108 { 109 struct proc *proc; 110 111 PFS_TRACE(("%s (pid: %d, req: %d)", 112 pn->pn_name, pid, td->td_proc->p_pid)); 113 114 if (p) 115 *p = NULL; 116 if (pid == NO_PID) 117 PFS_RETURN (1); 118 if ((proc = pfind(pid)) == NULL) 119 PFS_RETURN (0); 120 if (pfs_visible_proc(td, pn, proc)) { 121 if (p) 122 *p = proc; 123 else 124 PROC_UNLOCK(proc); 125 PFS_RETURN (1); 126 } 127 PROC_UNLOCK(proc); 128 PFS_RETURN (0); 129 } 130 131 /* 132 * Verify permissions 133 */ 134 static int 135 pfs_access(struct vop_access_args *va) 136 { 137 struct vnode *vn = va->a_vp; 138 struct pfs_vdata *pvd = vn->v_data; 139 struct vattr vattr; 140 int error; 141 142 PFS_TRACE(("%s", pvd->pvd_pn->pn_name)); 143 (void)pvd; 144 145 error = VOP_GETATTR(vn, &vattr, va->a_cred); 146 if (error) 147 PFS_RETURN (error); 148 error = vaccess(vn->v_type, vattr.va_mode, vattr.va_uid, 149 vattr.va_gid, va->a_accmode, va->a_cred, NULL); 150 PFS_RETURN (error); 151 } 152 153 /* 154 * Close a file or directory 155 */ 156 static int 157 pfs_close(struct vop_close_args *va) 158 { 159 struct vnode *vn = va->a_vp; 160 struct pfs_vdata *pvd = vn->v_data; 161 struct pfs_node *pn = pvd->pvd_pn; 162 struct proc *proc; 163 int error; 164 165 PFS_TRACE(("%s", pn->pn_name)); 166 pfs_assert_not_owned(pn); 167 168 /* 169 * Do nothing unless this is the last close and the node has a 170 * last-close handler. 171 */ 172 if (vrefcnt(vn) > 1 || pn->pn_close == NULL) 173 PFS_RETURN (0); 174 175 if (pvd->pvd_pid != NO_PID) { 176 proc = pfind(pvd->pvd_pid); 177 } else { 178 proc = NULL; 179 } 180 181 error = pn_close(va->a_td, proc, pn); 182 183 if (proc != NULL) 184 PROC_UNLOCK(proc); 185 186 PFS_RETURN (error); 187 } 188 189 /* 190 * Get file attributes 191 */ 192 static int 193 pfs_getattr(struct vop_getattr_args *va) 194 { 195 struct vnode *vn = va->a_vp; 196 struct pfs_vdata *pvd = vn->v_data; 197 struct pfs_node *pn = pvd->pvd_pn; 198 struct vattr *vap = va->a_vap; 199 struct proc *proc; 200 int error = 0; 201 202 PFS_TRACE(("%s", pn->pn_name)); 203 pfs_assert_not_owned(pn); 204 205 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 206 PFS_RETURN (ENOENT); 207 208 vap->va_type = vn->v_type; 209 vap->va_fileid = pn_fileno(pn, pvd->pvd_pid); 210 vap->va_flags = 0; 211 vap->va_blocksize = PAGE_SIZE; 212 vap->va_bytes = vap->va_size = 0; 213 vap->va_filerev = 0; 214 vap->va_fsid = vn->v_mount->mnt_stat.f_fsid.val[0]; 215 vap->va_nlink = 1; 216 nanotime(&vap->va_ctime); 217 vap->va_atime = vap->va_mtime = vap->va_ctime; 218 219 switch (pn->pn_type) { 220 case pfstype_procdir: 221 case pfstype_root: 222 case pfstype_dir: 223 #if 0 224 pfs_lock(pn); 225 /* compute link count */ 226 pfs_unlock(pn); 227 #endif 228 vap->va_mode = 0555; 229 break; 230 case pfstype_file: 231 case pfstype_symlink: 232 vap->va_mode = 0444; 233 break; 234 default: 235 printf("shouldn't be here!\n"); 236 vap->va_mode = 0; 237 break; 238 } 239 240 if (proc != NULL) { 241 vap->va_uid = proc->p_ucred->cr_ruid; 242 vap->va_gid = proc->p_ucred->cr_rgid; 243 } else { 244 vap->va_uid = 0; 245 vap->va_gid = 0; 246 } 247 248 if (pn->pn_attr != NULL) 249 error = pn_attr(curthread, proc, pn, vap); 250 251 if(proc != NULL) 252 PROC_UNLOCK(proc); 253 254 PFS_RETURN (error); 255 } 256 257 /* 258 * Perform an ioctl 259 */ 260 static int 261 pfs_ioctl(struct vop_ioctl_args *va) 262 { 263 struct vnode *vn; 264 struct pfs_vdata *pvd; 265 struct pfs_node *pn; 266 struct proc *proc; 267 int error; 268 269 vn = va->a_vp; 270 vn_lock(vn, LK_SHARED | LK_RETRY); 271 if (vn->v_iflag & VI_DOOMED) { 272 VOP_UNLOCK(vn, 0); 273 return (EBADF); 274 } 275 pvd = vn->v_data; 276 pn = pvd->pvd_pn; 277 278 PFS_TRACE(("%s: %lx", pn->pn_name, va->a_command)); 279 pfs_assert_not_owned(pn); 280 281 if (vn->v_type != VREG) { 282 VOP_UNLOCK(vn, 0); 283 PFS_RETURN (EINVAL); 284 } 285 KASSERT_PN_IS_FILE(pn); 286 287 if (pn->pn_ioctl == NULL) { 288 VOP_UNLOCK(vn, 0); 289 PFS_RETURN (ENOTTY); 290 } 291 292 /* 293 * This is necessary because process' privileges may 294 * have changed since the open() call. 295 */ 296 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) { 297 VOP_UNLOCK(vn, 0); 298 PFS_RETURN (EIO); 299 } 300 301 error = pn_ioctl(curthread, proc, pn, va->a_command, va->a_data); 302 303 if (proc != NULL) 304 PROC_UNLOCK(proc); 305 306 VOP_UNLOCK(vn, 0); 307 PFS_RETURN (error); 308 } 309 310 /* 311 * Perform getextattr 312 */ 313 static int 314 pfs_getextattr(struct vop_getextattr_args *va) 315 { 316 struct vnode *vn = va->a_vp; 317 struct pfs_vdata *pvd = vn->v_data; 318 struct pfs_node *pn = pvd->pvd_pn; 319 struct proc *proc; 320 int error; 321 322 PFS_TRACE(("%s", pn->pn_name)); 323 pfs_assert_not_owned(pn); 324 325 /* 326 * This is necessary because either process' privileges may 327 * have changed since the open() call. 328 */ 329 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 330 PFS_RETURN (EIO); 331 332 if (pn->pn_getextattr == NULL) 333 error = EOPNOTSUPP; 334 else 335 error = pn_getextattr(curthread, proc, pn, 336 va->a_attrnamespace, va->a_name, va->a_uio, 337 va->a_size, va->a_cred); 338 339 if (proc != NULL) 340 PROC_UNLOCK(proc); 341 342 PFS_RETURN (error); 343 } 344 345 /* 346 * Convert a vnode to its component name 347 */ 348 static int 349 pfs_vptocnp(struct vop_vptocnp_args *ap) 350 { 351 struct vnode *vp = ap->a_vp; 352 struct vnode **dvp = ap->a_vpp; 353 struct pfs_vdata *pvd = vp->v_data; 354 struct pfs_node *pd = pvd->pvd_pn; 355 struct pfs_node *pn; 356 struct mount *mp; 357 char *buf = ap->a_buf; 358 int *buflen = ap->a_buflen; 359 char pidbuf[PFS_NAMELEN]; 360 pid_t pid = pvd->pvd_pid; 361 int len, i, error, locked; 362 363 i = *buflen; 364 error = 0; 365 366 pfs_lock(pd); 367 368 if (vp->v_type == VDIR && pd->pn_type == pfstype_root) { 369 *dvp = vp; 370 vhold(*dvp); 371 pfs_unlock(pd); 372 PFS_RETURN (0); 373 } else if (vp->v_type == VDIR && pd->pn_type == pfstype_procdir) { 374 len = snprintf(pidbuf, sizeof(pidbuf), "%d", pid); 375 i -= len; 376 if (i < 0) { 377 error = ENOMEM; 378 goto failed; 379 } 380 bcopy(pidbuf, buf + i, len); 381 } else { 382 len = strlen(pd->pn_name); 383 i -= len; 384 if (i < 0) { 385 error = ENOMEM; 386 goto failed; 387 } 388 bcopy(pd->pn_name, buf + i, len); 389 } 390 391 pn = pd->pn_parent; 392 pfs_unlock(pd); 393 394 mp = vp->v_mount; 395 error = vfs_busy(mp, 0); 396 if (error) 397 return (error); 398 399 /* 400 * vp is held by caller. 401 */ 402 locked = VOP_ISLOCKED(vp); 403 VOP_UNLOCK(vp, 0); 404 405 error = pfs_vncache_alloc(mp, dvp, pn, pid); 406 if (error) { 407 vn_lock(vp, locked | LK_RETRY); 408 vfs_unbusy(mp); 409 PFS_RETURN(error); 410 } 411 412 *buflen = i; 413 vhold(*dvp); 414 vput(*dvp); 415 vn_lock(vp, locked | LK_RETRY); 416 vfs_unbusy(mp); 417 418 PFS_RETURN (0); 419 failed: 420 pfs_unlock(pd); 421 PFS_RETURN(error); 422 } 423 424 /* 425 * Look up a file or directory 426 */ 427 static int 428 pfs_lookup(struct vop_cachedlookup_args *va) 429 { 430 struct vnode *vn = va->a_dvp; 431 struct vnode **vpp = va->a_vpp; 432 struct componentname *cnp = va->a_cnp; 433 struct pfs_vdata *pvd = vn->v_data; 434 struct pfs_node *pd = pvd->pvd_pn; 435 struct pfs_node *pn, *pdn = NULL; 436 pid_t pid = pvd->pvd_pid; 437 char *pname; 438 int error, i, namelen, visible; 439 440 PFS_TRACE(("%.*s", (int)cnp->cn_namelen, cnp->cn_nameptr)); 441 pfs_assert_not_owned(pd); 442 443 if (vn->v_type != VDIR) 444 PFS_RETURN (ENOTDIR); 445 KASSERT_PN_IS_DIR(pd); 446 447 error = VOP_ACCESS(vn, VEXEC, cnp->cn_cred, cnp->cn_thread); 448 if (error) 449 PFS_RETURN (error); 450 451 /* 452 * Don't support DELETE or RENAME. CREATE is supported so 453 * that O_CREAT will work, but the lookup will still fail if 454 * the file does not exist. 455 */ 456 if ((cnp->cn_flags & ISLASTCN) && 457 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) 458 PFS_RETURN (EOPNOTSUPP); 459 460 /* shortcut: check if the name is too long */ 461 if (cnp->cn_namelen >= PFS_NAMELEN) 462 PFS_RETURN (ENOENT); 463 464 /* check that parent directory is visible... */ 465 if (!pfs_visible(curthread, pd, pvd->pvd_pid, NULL)) 466 PFS_RETURN (ENOENT); 467 468 /* self */ 469 namelen = cnp->cn_namelen; 470 pname = cnp->cn_nameptr; 471 if (namelen == 1 && pname[0] == '.') { 472 pn = pd; 473 *vpp = vn; 474 VREF(vn); 475 PFS_RETURN (0); 476 } 477 478 /* parent */ 479 if (cnp->cn_flags & ISDOTDOT) { 480 if (pd->pn_type == pfstype_root) 481 PFS_RETURN (EIO); 482 VOP_UNLOCK(vn, 0); 483 KASSERT(pd->pn_parent != NULL, 484 ("%s(): non-root directory has no parent", __func__)); 485 /* 486 * This one is tricky. Descendents of procdir nodes 487 * inherit their parent's process affinity, but 488 * there's no easy reverse mapping. For simplicity, 489 * we assume that if this node is a procdir, its 490 * parent isn't (which is correct as long as 491 * descendents of procdir nodes are never procdir 492 * nodes themselves) 493 */ 494 if (pd->pn_type == pfstype_procdir) 495 pid = NO_PID; 496 pfs_lock(pd); 497 pn = pd->pn_parent; 498 pfs_unlock(pd); 499 goto got_pnode; 500 } 501 502 pfs_lock(pd); 503 504 /* named node */ 505 for (pn = pd->pn_nodes; pn != NULL; pn = pn->pn_next) 506 if (pn->pn_type == pfstype_procdir) 507 pdn = pn; 508 else if (pn->pn_name[namelen] == '\0' && 509 bcmp(pname, pn->pn_name, namelen) == 0) { 510 pfs_unlock(pd); 511 goto got_pnode; 512 } 513 514 /* process dependent node */ 515 if ((pn = pdn) != NULL) { 516 pid = 0; 517 for (pid = 0, i = 0; i < namelen && isdigit(pname[i]); ++i) 518 if ((pid = pid * 10 + pname[i] - '0') > PID_MAX) 519 break; 520 if (i == cnp->cn_namelen) { 521 pfs_unlock(pd); 522 goto got_pnode; 523 } 524 } 525 526 pfs_unlock(pd); 527 528 PFS_RETURN (ENOENT); 529 530 got_pnode: 531 pfs_assert_not_owned(pd); 532 pfs_assert_not_owned(pn); 533 visible = pfs_visible(curthread, pn, pid, NULL); 534 if (!visible) { 535 error = ENOENT; 536 goto failed; 537 } 538 539 error = pfs_vncache_alloc(vn->v_mount, vpp, pn, pid); 540 if (error) 541 goto failed; 542 543 if (cnp->cn_flags & ISDOTDOT) 544 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY); 545 if (cnp->cn_flags & MAKEENTRY) 546 cache_enter(vn, *vpp, cnp); 547 PFS_RETURN (0); 548 failed: 549 if (cnp->cn_flags & ISDOTDOT) 550 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY); 551 PFS_RETURN(error); 552 } 553 554 /* 555 * Open a file or directory. 556 */ 557 static int 558 pfs_open(struct vop_open_args *va) 559 { 560 struct vnode *vn = va->a_vp; 561 struct pfs_vdata *pvd = vn->v_data; 562 struct pfs_node *pn = pvd->pvd_pn; 563 int mode = va->a_mode; 564 565 PFS_TRACE(("%s (mode 0x%x)", pn->pn_name, mode)); 566 pfs_assert_not_owned(pn); 567 568 /* check if the requested mode is permitted */ 569 if (((mode & FREAD) && !(mode & PFS_RD)) || 570 ((mode & FWRITE) && !(mode & PFS_WR))) 571 PFS_RETURN (EPERM); 572 573 /* we don't support locking */ 574 if ((mode & O_SHLOCK) || (mode & O_EXLOCK)) 575 PFS_RETURN (EOPNOTSUPP); 576 577 PFS_RETURN (0); 578 } 579 580 /* 581 * Read from a file 582 */ 583 static int 584 pfs_read(struct vop_read_args *va) 585 { 586 struct vnode *vn = va->a_vp; 587 struct pfs_vdata *pvd = vn->v_data; 588 struct pfs_node *pn = pvd->pvd_pn; 589 struct uio *uio = va->a_uio; 590 struct proc *proc; 591 struct sbuf *sb = NULL; 592 int error, locked; 593 unsigned int buflen, offset, resid; 594 595 PFS_TRACE(("%s", pn->pn_name)); 596 pfs_assert_not_owned(pn); 597 598 if (vn->v_type != VREG) 599 PFS_RETURN (EINVAL); 600 KASSERT_PN_IS_FILE(pn); 601 602 if (!(pn->pn_flags & PFS_RD)) 603 PFS_RETURN (EBADF); 604 605 if (pn->pn_fill == NULL) 606 PFS_RETURN (EIO); 607 608 /* 609 * This is necessary because either process' privileges may 610 * have changed since the open() call. 611 */ 612 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 613 PFS_RETURN (EIO); 614 if (proc != NULL) { 615 _PHOLD(proc); 616 PROC_UNLOCK(proc); 617 } 618 619 vhold(vn); 620 locked = VOP_ISLOCKED(vn); 621 VOP_UNLOCK(vn, 0); 622 623 if (pn->pn_flags & PFS_RAWRD) { 624 PFS_TRACE(("%zd resid", uio->uio_resid)); 625 error = pn_fill(curthread, proc, pn, NULL, uio); 626 PFS_TRACE(("%zd resid", uio->uio_resid)); 627 goto ret; 628 } 629 630 /* beaucoup sanity checks so we don't ask for bogus allocation */ 631 if (uio->uio_offset < 0 || uio->uio_resid < 0 || 632 (offset = uio->uio_offset) != uio->uio_offset || 633 (resid = uio->uio_resid) != uio->uio_resid || 634 (buflen = offset + resid + 1) < offset || buflen > INT_MAX) { 635 if (proc != NULL) 636 PRELE(proc); 637 error = EINVAL; 638 goto ret; 639 } 640 if (buflen > MAXPHYS + 1) { 641 error = EIO; 642 goto ret; 643 } 644 645 sb = sbuf_new(sb, NULL, buflen, 0); 646 if (sb == NULL) { 647 error = EIO; 648 goto ret; 649 } 650 651 error = pn_fill(curthread, proc, pn, sb, uio); 652 653 if (error) { 654 sbuf_delete(sb); 655 goto ret; 656 } 657 658 sbuf_finish(sb); 659 error = uiomove_frombuf(sbuf_data(sb), sbuf_len(sb), uio); 660 sbuf_delete(sb); 661 ret: 662 vn_lock(vn, locked | LK_RETRY); 663 vdrop(vn); 664 if (proc != NULL) 665 PRELE(proc); 666 PFS_RETURN (error); 667 } 668 669 /* 670 * Iterate through directory entries 671 */ 672 static int 673 pfs_iterate(struct thread *td, struct proc *proc, struct pfs_node *pd, 674 struct pfs_node **pn, struct proc **p) 675 { 676 int visible; 677 678 sx_assert(&allproc_lock, SX_SLOCKED); 679 pfs_assert_owned(pd); 680 again: 681 if (*pn == NULL) { 682 /* first node */ 683 *pn = pd->pn_nodes; 684 } else if ((*pn)->pn_type != pfstype_procdir) { 685 /* next node */ 686 *pn = (*pn)->pn_next; 687 } 688 if (*pn != NULL && (*pn)->pn_type == pfstype_procdir) { 689 /* next process */ 690 if (*p == NULL) 691 *p = LIST_FIRST(&allproc); 692 else 693 *p = LIST_NEXT(*p, p_list); 694 /* out of processes: next node */ 695 if (*p == NULL) 696 *pn = (*pn)->pn_next; 697 else 698 PROC_LOCK(*p); 699 } 700 701 if ((*pn) == NULL) 702 return (-1); 703 704 if (*p != NULL) { 705 visible = pfs_visible_proc(td, *pn, *p); 706 PROC_UNLOCK(*p); 707 } else if (proc != NULL) { 708 visible = pfs_visible_proc(td, *pn, proc); 709 } else { 710 visible = 1; 711 } 712 if (!visible) 713 goto again; 714 715 return (0); 716 } 717 718 /* 719 * Return directory entries. 720 */ 721 static int 722 pfs_readdir(struct vop_readdir_args *va) 723 { 724 struct vnode *vn = va->a_vp; 725 struct pfs_vdata *pvd = vn->v_data; 726 struct pfs_node *pd = pvd->pvd_pn; 727 pid_t pid = pvd->pvd_pid; 728 struct proc *p, *proc; 729 struct pfs_node *pn; 730 struct dirent *entry; 731 struct uio *uio; 732 off_t offset; 733 int error, i, resid; 734 char *buf, *ent; 735 736 KASSERT(pd->pn_info == vn->v_mount->mnt_data, 737 ("%s(): pn_info does not match mountpoint", __func__)); 738 PFS_TRACE(("%s pid %lu", pd->pn_name, (unsigned long)pid)); 739 pfs_assert_not_owned(pd); 740 741 if (vn->v_type != VDIR) 742 PFS_RETURN (ENOTDIR); 743 KASSERT_PN_IS_DIR(pd); 744 uio = va->a_uio; 745 746 /* only allow reading entire entries */ 747 offset = uio->uio_offset; 748 resid = uio->uio_resid; 749 if (offset < 0 || offset % PFS_DELEN != 0 || 750 (resid && resid < PFS_DELEN)) 751 PFS_RETURN (EINVAL); 752 if (resid == 0) 753 PFS_RETURN (0); 754 755 /* can't do this while holding the proc lock... */ 756 buf = malloc(resid, M_IOV, M_WAITOK | M_ZERO); 757 sx_slock(&allproc_lock); 758 pfs_lock(pd); 759 760 /* check if the directory is visible to the caller */ 761 if (!pfs_visible(curthread, pd, pid, &proc)) { 762 sx_sunlock(&allproc_lock); 763 pfs_unlock(pd); 764 free(buf, M_IOV); 765 PFS_RETURN (ENOENT); 766 } 767 KASSERT(pid == NO_PID || proc != NULL, 768 ("%s(): no process for pid %lu", __func__, (unsigned long)pid)); 769 770 /* skip unwanted entries */ 771 for (pn = NULL, p = NULL; offset > 0; offset -= PFS_DELEN) { 772 if (pfs_iterate(curthread, proc, pd, &pn, &p) == -1) { 773 /* nothing left... */ 774 if (proc != NULL) 775 PROC_UNLOCK(proc); 776 pfs_unlock(pd); 777 sx_sunlock(&allproc_lock); 778 free(buf, M_IOV); 779 PFS_RETURN (0); 780 } 781 } 782 783 /* fill in entries */ 784 ent = buf; 785 while (pfs_iterate(curthread, proc, pd, &pn, &p) != -1 && 786 resid >= PFS_DELEN) { 787 entry = (struct dirent *)ent; 788 entry->d_reclen = PFS_DELEN; 789 entry->d_fileno = pn_fileno(pn, pid); 790 /* PFS_DELEN was picked to fit PFS_NAMLEN */ 791 for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i) 792 entry->d_name[i] = pn->pn_name[i]; 793 entry->d_name[i] = 0; 794 entry->d_namlen = i; 795 switch (pn->pn_type) { 796 case pfstype_procdir: 797 KASSERT(p != NULL, 798 ("reached procdir node with p == NULL")); 799 entry->d_namlen = snprintf(entry->d_name, 800 PFS_NAMELEN, "%d", p->p_pid); 801 /* fall through */ 802 case pfstype_root: 803 case pfstype_dir: 804 case pfstype_this: 805 case pfstype_parent: 806 entry->d_type = DT_DIR; 807 break; 808 case pfstype_file: 809 entry->d_type = DT_REG; 810 break; 811 case pfstype_symlink: 812 entry->d_type = DT_LNK; 813 break; 814 default: 815 panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type); 816 } 817 PFS_TRACE(("%s", entry->d_name)); 818 offset += PFS_DELEN; 819 resid -= PFS_DELEN; 820 ent += PFS_DELEN; 821 } 822 if (proc != NULL) 823 PROC_UNLOCK(proc); 824 pfs_unlock(pd); 825 sx_sunlock(&allproc_lock); 826 PFS_TRACE(("%zd bytes", ent - buf)); 827 error = uiomove(buf, ent - buf, uio); 828 free(buf, M_IOV); 829 PFS_RETURN (error); 830 } 831 832 /* 833 * Read a symbolic link 834 */ 835 static int 836 pfs_readlink(struct vop_readlink_args *va) 837 { 838 struct vnode *vn = va->a_vp; 839 struct pfs_vdata *pvd = vn->v_data; 840 struct pfs_node *pn = pvd->pvd_pn; 841 struct uio *uio = va->a_uio; 842 struct proc *proc = NULL; 843 char buf[PATH_MAX]; 844 struct sbuf sb; 845 int error, locked; 846 847 PFS_TRACE(("%s", pn->pn_name)); 848 pfs_assert_not_owned(pn); 849 850 if (vn->v_type != VLNK) 851 PFS_RETURN (EINVAL); 852 KASSERT_PN_IS_LINK(pn); 853 854 if (pn->pn_fill == NULL) 855 PFS_RETURN (EIO); 856 857 if (pvd->pvd_pid != NO_PID) { 858 if ((proc = pfind(pvd->pvd_pid)) == NULL) 859 PFS_RETURN (EIO); 860 if (proc->p_flag & P_WEXIT) { 861 PROC_UNLOCK(proc); 862 PFS_RETURN (EIO); 863 } 864 _PHOLD(proc); 865 PROC_UNLOCK(proc); 866 } 867 vhold(vn); 868 locked = VOP_ISLOCKED(vn); 869 VOP_UNLOCK(vn, 0); 870 871 /* sbuf_new() can't fail with a static buffer */ 872 sbuf_new(&sb, buf, sizeof buf, 0); 873 874 error = pn_fill(curthread, proc, pn, &sb, NULL); 875 876 if (proc != NULL) 877 PRELE(proc); 878 vn_lock(vn, locked | LK_RETRY); 879 vdrop(vn); 880 881 if (error) { 882 sbuf_delete(&sb); 883 PFS_RETURN (error); 884 } 885 886 sbuf_finish(&sb); 887 error = uiomove_frombuf(sbuf_data(&sb), sbuf_len(&sb), uio); 888 sbuf_delete(&sb); 889 PFS_RETURN (error); 890 } 891 892 /* 893 * Reclaim a vnode 894 */ 895 static int 896 pfs_reclaim(struct vop_reclaim_args *va) 897 { 898 struct vnode *vn = va->a_vp; 899 struct pfs_vdata *pvd = vn->v_data; 900 struct pfs_node *pn = pvd->pvd_pn; 901 902 PFS_TRACE(("%s", pn->pn_name)); 903 pfs_assert_not_owned(pn); 904 905 return (pfs_vncache_free(va->a_vp)); 906 } 907 908 /* 909 * Set attributes 910 */ 911 static int 912 pfs_setattr(struct vop_setattr_args *va) 913 { 914 struct vnode *vn = va->a_vp; 915 struct pfs_vdata *pvd = vn->v_data; 916 struct pfs_node *pn = pvd->pvd_pn; 917 918 PFS_TRACE(("%s", pn->pn_name)); 919 pfs_assert_not_owned(pn); 920 921 PFS_RETURN (EOPNOTSUPP); 922 } 923 924 /* 925 * Write to a file 926 */ 927 static int 928 pfs_write(struct vop_write_args *va) 929 { 930 struct vnode *vn = va->a_vp; 931 struct pfs_vdata *pvd = vn->v_data; 932 struct pfs_node *pn = pvd->pvd_pn; 933 struct uio *uio = va->a_uio; 934 struct proc *proc; 935 struct sbuf sb; 936 int error; 937 938 PFS_TRACE(("%s", pn->pn_name)); 939 pfs_assert_not_owned(pn); 940 941 if (vn->v_type != VREG) 942 PFS_RETURN (EINVAL); 943 KASSERT_PN_IS_FILE(pn); 944 945 if (!(pn->pn_flags & PFS_WR)) 946 PFS_RETURN (EBADF); 947 948 if (pn->pn_fill == NULL) 949 PFS_RETURN (EIO); 950 951 /* 952 * This is necessary because either process' privileges may 953 * have changed since the open() call. 954 */ 955 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 956 PFS_RETURN (EIO); 957 if (proc != NULL) { 958 _PHOLD(proc); 959 PROC_UNLOCK(proc); 960 } 961 962 if (pn->pn_flags & PFS_RAWWR) { 963 error = pn_fill(curthread, proc, pn, NULL, uio); 964 if (proc != NULL) 965 PRELE(proc); 966 PFS_RETURN (error); 967 } 968 969 sbuf_uionew(&sb, uio, &error); 970 if (error) { 971 if (proc != NULL) 972 PRELE(proc); 973 PFS_RETURN (error); 974 } 975 976 error = pn_fill(curthread, proc, pn, &sb, uio); 977 978 sbuf_delete(&sb); 979 if (proc != NULL) 980 PRELE(proc); 981 PFS_RETURN (error); 982 } 983 984 /* 985 * Vnode operations 986 */ 987 struct vop_vector pfs_vnodeops = { 988 .vop_default = &default_vnodeops, 989 990 .vop_access = pfs_access, 991 .vop_cachedlookup = pfs_lookup, 992 .vop_close = pfs_close, 993 .vop_create = VOP_EOPNOTSUPP, 994 .vop_getattr = pfs_getattr, 995 .vop_getextattr = pfs_getextattr, 996 .vop_ioctl = pfs_ioctl, 997 .vop_link = VOP_EOPNOTSUPP, 998 .vop_lookup = vfs_cache_lookup, 999 .vop_mkdir = VOP_EOPNOTSUPP, 1000 .vop_mknod = VOP_EOPNOTSUPP, 1001 .vop_open = pfs_open, 1002 .vop_read = pfs_read, 1003 .vop_readdir = pfs_readdir, 1004 .vop_readlink = pfs_readlink, 1005 .vop_reclaim = pfs_reclaim, 1006 .vop_remove = VOP_EOPNOTSUPP, 1007 .vop_rename = VOP_EOPNOTSUPP, 1008 .vop_rmdir = VOP_EOPNOTSUPP, 1009 .vop_setattr = pfs_setattr, 1010 .vop_symlink = VOP_EOPNOTSUPP, 1011 .vop_vptocnp = pfs_vptocnp, 1012 .vop_write = pfs_write, 1013 /* XXX I've probably forgotten a few that need VOP_EOPNOTSUPP */ 1014 }; 1015