| 1 | /* |
| 2 | * Copyright (c) 1993, 1995 Jan-Simon Pendry |
| 3 | * Copyright (c) 1993, 1995 |
| 4 | * The Regents of the University of California. All rights reserved. |
| 5 | * |
| 6 | * This code is derived from software contributed to Berkeley by |
| 7 | * Jan-Simon Pendry. |
| 8 | * |
| 9 | * Redistribution and use in source and binary forms, with or without |
| 10 | * modification, are permitted provided that the following conditions |
| 11 | * are met: |
| 12 | * 1. Redistributions of source code must retain the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer. |
| 14 | * 2. Redistributions in binary form must reproduce the above copyright |
| 15 | * notice, this list of conditions and the following disclaimer in the |
| 16 | * documentation and/or other materials provided with the distribution. |
| 17 | * 3. All advertising materials mentioning features or use of this software |
| 18 | * must display the following acknowledgement: |
| 19 | * This product includes software developed by the University of |
| 20 | * California, Berkeley and its contributors. |
| 21 | * 4. Neither the name of the University nor the names of its contributors |
| 22 | * may be used to endorse or promote products derived from this software |
| 23 | * without specific prior written permission. |
| 24 | * |
| 25 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 26 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 27 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 28 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 29 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 30 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 31 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 32 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 33 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 34 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 35 | * SUCH DAMAGE. |
| 36 | * |
| 37 | * @(#)procfs_vnops.c 8.18 (Berkeley) 5/21/95 |
| 38 | * |
| 39 | * $FreeBSD: src/sys/miscfs/procfs/procfs_vnops.c,v 1.76.2.7 2002/01/22 17:22:59 nectar Exp $ |
| 40 | */ |
| 41 | |
| 42 | /* |
| 43 | * procfs vnode interface |
| 44 | */ |
| 45 | |
| 46 | #include <sys/param.h> |
| 47 | #include <sys/systm.h> |
| 48 | #include <sys/time.h> |
| 49 | #include <sys/kernel.h> |
| 50 | #include <sys/lock.h> |
| 51 | #include <sys/fcntl.h> |
| 52 | #include <sys/proc.h> |
| 53 | #include <sys/priv.h> |
| 54 | #include <sys/signalvar.h> |
| 55 | #include <sys/vnode.h> |
| 56 | #include <sys/uio.h> |
| 57 | #include <sys/mount.h> |
| 58 | #include <sys/namei.h> |
| 59 | #include <sys/dirent.h> |
| 60 | #include <sys/malloc.h> |
| 61 | #include <sys/reg.h> |
| 62 | #include <vm/vm_zone.h> |
| 63 | #include <vfs/procfs/procfs.h> |
| 64 | #include <sys/pioctl.h> |
| 65 | |
| 66 | #include <sys/spinlock2.h> |
| 67 | |
| 68 | #include <machine/limits.h> |
| 69 | |
| 70 | static int procfs_access (struct vop_access_args *); |
| 71 | static int procfs_badop (struct vop_generic_args *); |
| 72 | static int procfs_bmap (struct vop_bmap_args *); |
| 73 | static int procfs_close (struct vop_close_args *); |
| 74 | static int procfs_getattr (struct vop_getattr_args *); |
| 75 | static int procfs_inactive (struct vop_inactive_args *); |
| 76 | static int procfs_ioctl (struct vop_ioctl_args *); |
| 77 | static int procfs_lookup (struct vop_old_lookup_args *); |
| 78 | static int procfs_open (struct vop_open_args *); |
| 79 | static int procfs_print (struct vop_print_args *); |
| 80 | static int procfs_readdir (struct vop_readdir_args *); |
| 81 | static int procfs_readlink (struct vop_readlink_args *); |
| 82 | static int procfs_reclaim (struct vop_reclaim_args *); |
| 83 | static int procfs_setattr (struct vop_setattr_args *); |
| 84 | |
| 85 | static int procfs_readdir_proc(struct vop_readdir_args *); |
| 86 | static int procfs_readdir_root(struct vop_readdir_args *); |
| 87 | |
| 88 | /* |
| 89 | * procfs vnode operations. |
| 90 | */ |
| 91 | struct vop_ops procfs_vnode_vops = { |
| 92 | .vop_default = vop_defaultop, |
| 93 | .vop_access = procfs_access, |
| 94 | .vop_advlock = (void *)procfs_badop, |
| 95 | .vop_bmap = procfs_bmap, |
| 96 | .vop_close = procfs_close, |
| 97 | .vop_old_create = (void *)procfs_badop, |
| 98 | .vop_getattr = procfs_getattr, |
| 99 | .vop_inactive = procfs_inactive, |
| 100 | .vop_old_link = (void *)procfs_badop, |
| 101 | .vop_old_lookup = procfs_lookup, |
| 102 | .vop_old_mkdir = (void *)procfs_badop, |
| 103 | .vop_old_mknod = (void *)procfs_badop, |
| 104 | .vop_open = procfs_open, |
| 105 | .vop_pathconf = vop_stdpathconf, |
| 106 | .vop_print = procfs_print, |
| 107 | .vop_read = procfs_rw, |
| 108 | .vop_readdir = procfs_readdir, |
| 109 | .vop_readlink = procfs_readlink, |
| 110 | .vop_reclaim = procfs_reclaim, |
| 111 | .vop_old_remove = (void *)procfs_badop, |
| 112 | .vop_old_rename = (void *)procfs_badop, |
| 113 | .vop_old_rmdir = (void *)procfs_badop, |
| 114 | .vop_setattr = procfs_setattr, |
| 115 | .vop_old_symlink = (void *)procfs_badop, |
| 116 | .vop_write = (void *)procfs_rw, |
| 117 | .vop_ioctl = procfs_ioctl |
| 118 | }; |
| 119 | |
| 120 | |
| 121 | /* |
| 122 | * This is a list of the valid names in the |
| 123 | * process-specific sub-directories. It is |
| 124 | * used in procfs_lookup and procfs_readdir |
| 125 | */ |
| 126 | static struct proc_target { |
| 127 | u_char pt_type; |
| 128 | u_char pt_namlen; |
| 129 | char *pt_name; |
| 130 | pfstype pt_pfstype; |
| 131 | int (*pt_valid) (struct lwp *p); |
| 132 | } proc_targets[] = { |
| 133 | #define N(s) sizeof(s)-1, s |
| 134 | /* name type validp */ |
| 135 | { DT_DIR, N("."), Pproc, NULL }, |
| 136 | { DT_DIR, N(".."), Proot, NULL }, |
| 137 | { DT_REG, N("mem"), Pmem, NULL }, |
| 138 | { DT_REG, N("regs"), Pregs, procfs_validregs }, |
| 139 | { DT_REG, N("fpregs"), Pfpregs, procfs_validfpregs }, |
| 140 | { DT_REG, N("dbregs"), Pdbregs, procfs_validdbregs }, |
| 141 | { DT_REG, N("ctl"), Pctl, NULL }, |
| 142 | { DT_REG, N("status"), Pstatus, NULL }, |
| 143 | { DT_REG, N("note"), Pnote, NULL }, |
| 144 | { DT_REG, N("notepg"), Pnotepg, NULL }, |
| 145 | { DT_REG, N("map"), Pmap, procfs_validmap }, |
| 146 | { DT_REG, N("etype"), Ptype, procfs_validtype }, |
| 147 | { DT_REG, N("cmdline"), Pcmdline, NULL }, |
| 148 | { DT_REG, N("rlimit"), Prlimit, NULL }, |
| 149 | { DT_LNK, N("file"), Pfile, NULL }, |
| 150 | #undef N |
| 151 | }; |
| 152 | static const int nproc_targets = NELEM(proc_targets); |
| 153 | |
| 154 | static pid_t atopid (const char *, u_int); |
| 155 | |
| 156 | /* |
| 157 | * set things up for doing i/o on |
| 158 | * the pfsnode (vp). (vp) is locked |
| 159 | * on entry, and should be left locked |
| 160 | * on exit. |
| 161 | * |
| 162 | * for procfs we don't need to do anything |
| 163 | * in particular for i/o. all that is done |
| 164 | * is to support exclusive open on process |
| 165 | * memory images. |
| 166 | * |
| 167 | * procfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred, |
| 168 | * struct file *a_fp) |
| 169 | */ |
| 170 | static int |
| 171 | procfs_open(struct vop_open_args *ap) |
| 172 | { |
| 173 | struct pfsnode *pfs = VTOPFS(ap->a_vp); |
| 174 | struct proc *p1, *p2; |
| 175 | int error; |
| 176 | |
| 177 | p2 = pfs_pfind(pfs->pfs_pid); |
| 178 | if (p2 == NULL) |
| 179 | return (ENOENT); |
| 180 | if (pfs->pfs_pid && !PRISON_CHECK(ap->a_cred, p2->p_ucred)) { |
| 181 | error = ENOENT; |
| 182 | goto done; |
| 183 | } |
| 184 | |
| 185 | switch (pfs->pfs_type) { |
| 186 | case Pmem: |
| 187 | if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) || |
| 188 | ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE))) { |
| 189 | error = EBUSY; |
| 190 | goto done; |
| 191 | } |
| 192 | |
| 193 | p1 = curproc; |
| 194 | KKASSERT(p1); |
| 195 | /* Can't trace a process that's currently exec'ing. */ |
| 196 | if ((p2->p_flags & P_INEXEC) != 0) { |
| 197 | error = EAGAIN; |
| 198 | goto done; |
| 199 | } |
| 200 | if (!CHECKIO(p1, p2) || p_trespass(ap->a_cred, p2->p_ucred)) { |
| 201 | error = EPERM; |
| 202 | goto done; |
| 203 | } |
| 204 | |
| 205 | if (ap->a_mode & FWRITE) |
| 206 | pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL); |
| 207 | |
| 208 | break; |
| 209 | |
| 210 | default: |
| 211 | break; |
| 212 | } |
| 213 | error = vop_stdopen(ap); |
| 214 | done: |
| 215 | PRELE(p2); |
| 216 | return error; |
| 217 | } |
| 218 | |
| 219 | /* |
| 220 | * close the pfsnode (vp) after doing i/o. |
| 221 | * (vp) is not locked on entry or exit. |
| 222 | * |
| 223 | * nothing to do for procfs other than undo |
| 224 | * any exclusive open flag (see _open above). |
| 225 | * |
| 226 | * procfs_close(struct vnode *a_vp, int a_fflag, struct ucred *a_cred) |
| 227 | */ |
| 228 | static int |
| 229 | procfs_close(struct vop_close_args *ap) |
| 230 | { |
| 231 | struct pfsnode *pfs = VTOPFS(ap->a_vp); |
| 232 | struct proc *p; |
| 233 | |
| 234 | switch (pfs->pfs_type) { |
| 235 | case Pmem: |
| 236 | if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL)) |
| 237 | pfs->pfs_flags &= ~(FWRITE|O_EXCL); |
| 238 | /* |
| 239 | * v_opencount determines the last real close on the vnode. |
| 240 | * |
| 241 | * If this is the last close, then it checks to see if |
| 242 | * the target process has PF_LINGER set in p_pfsflags, |
| 243 | * if this is *not* the case, then the process' stop flags |
| 244 | * are cleared, and the process is woken up. This is |
| 245 | * to help prevent the case where a process has been |
| 246 | * told to stop on an event, but then the requesting process |
| 247 | * has gone away or forgotten about it. |
| 248 | */ |
| 249 | p = NULL; |
| 250 | if ((ap->a_vp->v_opencount < 2) |
| 251 | && (p = pfind(pfs->pfs_pid)) |
| 252 | && !(p->p_pfsflags & PF_LINGER)) { |
| 253 | spin_lock(&p->p_spin); |
| 254 | p->p_stops = 0; |
| 255 | p->p_step = 0; |
| 256 | spin_unlock(&p->p_spin); |
| 257 | wakeup(&p->p_step); |
| 258 | } |
| 259 | if (p) |
| 260 | PRELE(p); |
| 261 | break; |
| 262 | default: |
| 263 | break; |
| 264 | } |
| 265 | |
| 266 | return (vop_stdclose(ap)); |
| 267 | } |
| 268 | |
| 269 | /* |
| 270 | * do an ioctl operation on a pfsnode (vp). |
| 271 | * (vp) is not locked on entry or exit. |
| 272 | */ |
| 273 | static int |
| 274 | procfs_ioctl(struct vop_ioctl_args *ap) |
| 275 | { |
| 276 | struct pfsnode *pfs = VTOPFS(ap->a_vp); |
| 277 | struct proc *procp; |
| 278 | struct proc *p; |
| 279 | int error; |
| 280 | int signo; |
| 281 | struct procfs_status *psp; |
| 282 | unsigned char flags; |
| 283 | |
| 284 | procp = pfind(pfs->pfs_pid); |
| 285 | if (procp == NULL) |
| 286 | return ENOTTY; |
| 287 | p = curproc; |
| 288 | if (p == NULL) { |
| 289 | error = EINVAL; |
| 290 | goto done; |
| 291 | } |
| 292 | |
| 293 | /* Can't trace a process that's currently exec'ing. */ |
| 294 | if ((procp->p_flags & P_INEXEC) != 0) { |
| 295 | error = EAGAIN; |
| 296 | goto done; |
| 297 | } |
| 298 | if (!CHECKIO(p, procp) || p_trespass(ap->a_cred, procp->p_ucred)) { |
| 299 | error = EPERM; |
| 300 | goto done; |
| 301 | } |
| 302 | |
| 303 | switch (ap->a_command) { |
| 304 | case PIOCBIS: |
| 305 | procp->p_stops |= *(unsigned int*)ap->a_data; |
| 306 | break; |
| 307 | case PIOCBIC: |
| 308 | procp->p_stops &= ~*(unsigned int*)ap->a_data; |
| 309 | break; |
| 310 | case PIOCSFL: |
| 311 | /* |
| 312 | * NFLAGS is "non-suser_xxx flags" -- currently, only |
| 313 | * PFS_ISUGID ("ignore set u/g id"); |
| 314 | */ |
| 315 | #define NFLAGS (PF_ISUGID) |
| 316 | flags = (unsigned char)*(unsigned int*)ap->a_data; |
| 317 | if (flags & NFLAGS && (error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0))) |
| 318 | goto done; |
| 319 | procp->p_pfsflags = flags; |
| 320 | break; |
| 321 | case PIOCGFL: |
| 322 | *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags; |
| 323 | break; |
| 324 | case PIOCSTATUS: |
| 325 | /* |
| 326 | * NOTE: syscall entry deals with stopevents and may run without |
| 327 | * the MP lock. |
| 328 | */ |
| 329 | psp = (struct procfs_status *)ap->a_data; |
| 330 | psp->flags = procp->p_pfsflags; |
| 331 | psp->events = procp->p_stops; |
| 332 | spin_lock(&procp->p_spin); |
| 333 | if (procp->p_step) { |
| 334 | psp->state = 0; |
| 335 | psp->why = procp->p_stype; |
| 336 | psp->val = procp->p_xstat; |
| 337 | spin_unlock(&procp->p_spin); |
| 338 | } else { |
| 339 | psp->state = 1; |
| 340 | spin_unlock(&procp->p_spin); |
| 341 | psp->why = 0; /* Not defined values */ |
| 342 | psp->val = 0; /* Not defined values */ |
| 343 | } |
| 344 | break; |
| 345 | case PIOCWAIT: |
| 346 | /* |
| 347 | * NOTE: syscall entry deals with stopevents and may run without |
| 348 | * the MP lock. |
| 349 | */ |
| 350 | psp = (struct procfs_status *)ap->a_data; |
| 351 | spin_lock(&procp->p_spin); |
| 352 | while (procp->p_step == 0) { |
| 353 | tsleep_interlock(&procp->p_stype, PCATCH); |
| 354 | spin_unlock(&procp->p_spin); |
| 355 | error = tsleep(&procp->p_stype, PCATCH | PINTERLOCKED, "piocwait", 0); |
| 356 | if (error) |
| 357 | goto done; |
| 358 | spin_lock(&procp->p_spin); |
| 359 | } |
| 360 | spin_unlock(&procp->p_spin); |
| 361 | psp->state = 1; /* It stopped */ |
| 362 | psp->flags = procp->p_pfsflags; |
| 363 | psp->events = procp->p_stops; |
| 364 | psp->why = procp->p_stype; /* why it stopped */ |
| 365 | psp->val = procp->p_xstat; /* any extra info */ |
| 366 | break; |
| 367 | case PIOCCONT: /* Restart a proc */ |
| 368 | /* |
| 369 | * NOTE: syscall entry deals with stopevents and may run without |
| 370 | * the MP lock. However, the caller is presumably interlocked |
| 371 | * by having waited. |
| 372 | */ |
| 373 | if (procp->p_step == 0) { |
| 374 | error = EINVAL; /* Can only start a stopped process */ |
| 375 | goto done; |
| 376 | } |
| 377 | if ((signo = *(int*)ap->a_data) != 0) { |
| 378 | if (signo >= NSIG || signo <= 0) { |
| 379 | error = EINVAL; |
| 380 | goto done; |
| 381 | } |
| 382 | ksignal(procp, signo); |
| 383 | } |
| 384 | procp->p_step = 0; |
| 385 | wakeup(&procp->p_step); |
| 386 | break; |
| 387 | default: |
| 388 | error = ENOTTY; |
| 389 | goto done; |
| 390 | } |
| 391 | error = 0; |
| 392 | done: |
| 393 | PRELE(procp); |
| 394 | return 0; |
| 395 | } |
| 396 | |
| 397 | /* |
| 398 | * do block mapping for pfsnode (vp). |
| 399 | * since we don't use the buffer cache |
| 400 | * for procfs this function should never |
| 401 | * be called. in any case, it's not clear |
| 402 | * what part of the kernel ever makes use |
| 403 | * of this function. for sanity, this is the |
| 404 | * usual no-op bmap, although returning |
| 405 | * (EIO) would be a reasonable alternative. |
| 406 | * |
| 407 | * XXX mmap assumes buffer cache operation |
| 408 | * |
| 409 | * procfs_bmap(struct vnode *a_vp, off_t a_loffset, |
| 410 | * off_t *a_doffsetp, int *a_runp, int *a_runb) |
| 411 | */ |
| 412 | static int |
| 413 | procfs_bmap(struct vop_bmap_args *ap) |
| 414 | { |
| 415 | if (ap->a_doffsetp != NULL) |
| 416 | *ap->a_doffsetp = ap->a_loffset; |
| 417 | if (ap->a_runp != NULL) |
| 418 | *ap->a_runp = 0; |
| 419 | if (ap->a_runb != NULL) |
| 420 | *ap->a_runb = 0; |
| 421 | return (0); |
| 422 | } |
| 423 | |
| 424 | /* |
| 425 | * procfs_inactive is called when the pfsnode |
| 426 | * is vrele'd and the reference count goes |
| 427 | * to zero. (vp) will be on the vnode free |
| 428 | * list, so to get it back vget() must be |
| 429 | * used. |
| 430 | * |
| 431 | * (vp) is locked on entry, but must be unlocked on exit. |
| 432 | * |
| 433 | * procfs_inactive(struct vnode *a_vp) |
| 434 | */ |
| 435 | static int |
| 436 | procfs_inactive(struct vop_inactive_args *ap) |
| 437 | { |
| 438 | struct pfsnode *pfs = VTOPFS(ap->a_vp); |
| 439 | |
| 440 | if (pfs->pfs_pid & PFS_DEAD) |
| 441 | vrecycle(ap->a_vp); |
| 442 | return (0); |
| 443 | } |
| 444 | |
| 445 | /* |
| 446 | * _reclaim is called when getnewvnode() |
| 447 | * wants to make use of an entry on the vnode |
| 448 | * free list. at this time the filesystem needs |
| 449 | * to free any private data and remove the node |
| 450 | * from any private lists. |
| 451 | * |
| 452 | * procfs_reclaim(struct vnode *a_vp) |
| 453 | */ |
| 454 | static int |
| 455 | procfs_reclaim(struct vop_reclaim_args *ap) |
| 456 | { |
| 457 | return (procfs_freevp(ap->a_vp)); |
| 458 | } |
| 459 | |
| 460 | /* |
| 461 | * _print is used for debugging. |
| 462 | * just print a readable description |
| 463 | * of (vp). |
| 464 | * |
| 465 | * procfs_print(struct vnode *a_vp) |
| 466 | */ |
| 467 | static int |
| 468 | procfs_print(struct vop_print_args *ap) |
| 469 | { |
| 470 | struct pfsnode *pfs = VTOPFS(ap->a_vp); |
| 471 | |
| 472 | kprintf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n", |
| 473 | pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags); |
| 474 | return (0); |
| 475 | } |
| 476 | |
| 477 | /* |
| 478 | * generic entry point for unsupported operations |
| 479 | */ |
| 480 | static int |
| 481 | procfs_badop(struct vop_generic_args *ap) |
| 482 | { |
| 483 | return (EIO); |
| 484 | } |
| 485 | |
| 486 | /* |
| 487 | * Invent attributes for pfsnode (vp) and store |
| 488 | * them in (vap). |
| 489 | * Directories lengths are returned as zero since |
| 490 | * any real length would require the genuine size |
| 491 | * to be computed, and nothing cares anyway. |
| 492 | * |
| 493 | * this is relatively minimal for procfs. |
| 494 | * |
| 495 | * procfs_getattr(struct vnode *a_vp, struct vattr *a_vap) |
| 496 | */ |
| 497 | static int |
| 498 | procfs_getattr(struct vop_getattr_args *ap) |
| 499 | { |
| 500 | struct pfsnode *pfs = VTOPFS(ap->a_vp); |
| 501 | struct vattr *vap = ap->a_vap; |
| 502 | struct proc *procp; |
| 503 | int error; |
| 504 | |
| 505 | /* |
| 506 | * First make sure that the process and its credentials |
| 507 | * still exist. |
| 508 | */ |
| 509 | switch (pfs->pfs_type) { |
| 510 | case Proot: |
| 511 | case Pcurproc: |
| 512 | procp = NULL; |
| 513 | break; |
| 514 | |
| 515 | default: |
| 516 | procp = pfs_pfind(pfs->pfs_pid); |
| 517 | if (procp == NULL || procp->p_ucred == NULL) { |
| 518 | error = ENOENT; |
| 519 | goto done; |
| 520 | } |
| 521 | } |
| 522 | |
| 523 | error = 0; |
| 524 | |
| 525 | /* start by zeroing out the attributes */ |
| 526 | VATTR_NULL(vap); |
| 527 | |
| 528 | /* next do all the common fields */ |
| 529 | vap->va_type = ap->a_vp->v_type; |
| 530 | vap->va_mode = pfs->pfs_mode; |
| 531 | vap->va_fileid = pfs->pfs_fileno; |
| 532 | vap->va_flags = 0; |
| 533 | vap->va_blocksize = PAGE_SIZE; |
| 534 | vap->va_bytes = vap->va_size = 0; |
| 535 | vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; |
| 536 | |
| 537 | /* |
| 538 | * Make all times be current TOD. |
| 539 | * It would be possible to get the process start |
| 540 | * time from the p_stat structure, but there's |
| 541 | * no "file creation" time stamp anyway, and the |
| 542 | * p_stat structure is not addressible if u. gets |
| 543 | * swapped out for that process. |
| 544 | */ |
| 545 | nanotime(&vap->va_ctime); |
| 546 | vap->va_atime = vap->va_mtime = vap->va_ctime; |
| 547 | |
| 548 | /* |
| 549 | * If the process has exercised some setuid or setgid |
| 550 | * privilege, then rip away read/write permission so |
| 551 | * that only root can gain access. |
| 552 | */ |
| 553 | switch (pfs->pfs_type) { |
| 554 | case Pctl: |
| 555 | case Pregs: |
| 556 | case Pfpregs: |
| 557 | case Pdbregs: |
| 558 | case Pmem: |
| 559 | if (procp->p_flags & P_SUGID) |
| 560 | vap->va_mode &= ~((VREAD|VWRITE)| |
| 561 | ((VREAD|VWRITE)>>3)| |
| 562 | ((VREAD|VWRITE)>>6)); |
| 563 | break; |
| 564 | default: |
| 565 | break; |
| 566 | } |
| 567 | |
| 568 | /* |
| 569 | * now do the object specific fields |
| 570 | * |
| 571 | * The size could be set from struct reg, but it's hardly |
| 572 | * worth the trouble, and it puts some (potentially) machine |
| 573 | * dependent data into this machine-independent code. If it |
| 574 | * becomes important then this function should break out into |
| 575 | * a per-file stat function in the corresponding .c file. |
| 576 | */ |
| 577 | |
| 578 | vap->va_nlink = 1; |
| 579 | if (procp) { |
| 580 | vap->va_uid = procp->p_ucred->cr_uid; |
| 581 | vap->va_gid = procp->p_ucred->cr_gid; |
| 582 | } |
| 583 | |
| 584 | switch (pfs->pfs_type) { |
| 585 | case Proot: |
| 586 | /* |
| 587 | * Set nlink to 1 to tell fts(3) we don't actually know. |
| 588 | */ |
| 589 | vap->va_nlink = 1; |
| 590 | vap->va_uid = 0; |
| 591 | vap->va_gid = 0; |
| 592 | vap->va_size = vap->va_bytes = DEV_BSIZE; |
| 593 | break; |
| 594 | |
| 595 | case Pcurproc: { |
| 596 | char buf[16]; /* should be enough */ |
| 597 | vap->va_uid = 0; |
| 598 | vap->va_gid = 0; |
| 599 | vap->va_size = vap->va_bytes = |
| 600 | ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); |
| 601 | break; |
| 602 | } |
| 603 | |
| 604 | case Pproc: |
| 605 | vap->va_nlink = nproc_targets; |
| 606 | vap->va_size = vap->va_bytes = DEV_BSIZE; |
| 607 | break; |
| 608 | |
| 609 | case Pfile: { |
| 610 | char *fullpath, *freepath; |
| 611 | error = cache_fullpath(procp, &procp->p_textnch, &fullpath, &freepath, 0); |
| 612 | if (error == 0) { |
| 613 | vap->va_size = strlen(fullpath); |
| 614 | kfree(freepath, M_TEMP); |
| 615 | } else { |
| 616 | vap->va_size = sizeof("unknown") - 1; |
| 617 | error = 0; |
| 618 | } |
| 619 | vap->va_bytes = vap->va_size; |
| 620 | break; |
| 621 | } |
| 622 | |
| 623 | case Pmem: |
| 624 | /* |
| 625 | * If we denied owner access earlier, then we have to |
| 626 | * change the owner to root - otherwise 'ps' and friends |
| 627 | * will break even though they are setgid kmem. *SIGH* |
| 628 | */ |
| 629 | if (procp->p_flags & P_SUGID) |
| 630 | vap->va_uid = 0; |
| 631 | else |
| 632 | vap->va_uid = procp->p_ucred->cr_uid; |
| 633 | break; |
| 634 | |
| 635 | case Pregs: |
| 636 | vap->va_bytes = vap->va_size = sizeof(struct reg); |
| 637 | break; |
| 638 | |
| 639 | case Pfpregs: |
| 640 | vap->va_bytes = vap->va_size = sizeof(struct fpreg); |
| 641 | break; |
| 642 | |
| 643 | case Pdbregs: |
| 644 | vap->va_bytes = vap->va_size = sizeof(struct dbreg); |
| 645 | break; |
| 646 | |
| 647 | case Ptype: |
| 648 | case Pmap: |
| 649 | case Pctl: |
| 650 | case Pstatus: |
| 651 | case Pnote: |
| 652 | case Pnotepg: |
| 653 | case Pcmdline: |
| 654 | case Prlimit: |
| 655 | break; |
| 656 | |
| 657 | default: |
| 658 | panic("procfs_getattr"); |
| 659 | } |
| 660 | done: |
| 661 | if (procp) |
| 662 | PRELE(procp); |
| 663 | return (error); |
| 664 | } |
| 665 | |
| 666 | /* |
| 667 | * procfs_setattr(struct vnode *a_vp, struct vattr *a_vap, |
| 668 | * struct ucred *a_cred) |
| 669 | */ |
| 670 | static int |
| 671 | procfs_setattr(struct vop_setattr_args *ap) |
| 672 | { |
| 673 | if (ap->a_vap->va_flags != VNOVAL) |
| 674 | return (EOPNOTSUPP); |
| 675 | |
| 676 | /* |
| 677 | * just fake out attribute setting |
| 678 | * it's not good to generate an error |
| 679 | * return, otherwise things like creat() |
| 680 | * will fail when they try to set the |
| 681 | * file length to 0. worse, this means |
| 682 | * that echo $note > /proc/$pid/note will fail. |
| 683 | */ |
| 684 | |
| 685 | return (0); |
| 686 | } |
| 687 | |
| 688 | /* |
| 689 | * implement access checking. |
| 690 | * |
| 691 | * procfs_access(struct vnode *a_vp, int a_mode, struct ucred *a_cred) |
| 692 | */ |
| 693 | static int |
| 694 | procfs_access(struct vop_access_args *ap) |
| 695 | { |
| 696 | struct vattr vattr; |
| 697 | int error; |
| 698 | |
| 699 | error = VOP_GETATTR(ap->a_vp, &vattr); |
| 700 | if (!error) |
| 701 | error = vop_helper_access(ap, vattr.va_uid, vattr.va_gid, |
| 702 | vattr.va_mode, 0); |
| 703 | return (error); |
| 704 | } |
| 705 | |
| 706 | /* |
| 707 | * lookup. this is incredibly complicated in the general case, however |
| 708 | * for most pseudo-filesystems very little needs to be done. |
| 709 | * |
| 710 | * procfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp, |
| 711 | * struct componentname *a_cnp) |
| 712 | */ |
| 713 | static int |
| 714 | procfs_lookup(struct vop_old_lookup_args *ap) |
| 715 | { |
| 716 | struct componentname *cnp = ap->a_cnp; |
| 717 | struct vnode **vpp = ap->a_vpp; |
| 718 | struct vnode *dvp = ap->a_dvp; |
| 719 | char *pname = cnp->cn_nameptr; |
| 720 | /* struct proc *curp = cnp->cn_proc; */ |
| 721 | struct proc_target *pt; |
| 722 | pid_t pid; |
| 723 | struct pfsnode *pfs; |
| 724 | struct proc *p; |
| 725 | struct lwp *lp; |
| 726 | int i; |
| 727 | int error; |
| 728 | |
| 729 | *vpp = NULL; |
| 730 | |
| 731 | if (cnp->cn_nameiop == NAMEI_DELETE || cnp->cn_nameiop == NAMEI_RENAME) |
| 732 | return (EROFS); |
| 733 | |
| 734 | p = NULL; |
| 735 | error = 0; |
| 736 | if (cnp->cn_namelen == 1 && *pname == '.') { |
| 737 | *vpp = dvp; |
| 738 | vref(*vpp); |
| 739 | goto out; |
| 740 | } |
| 741 | |
| 742 | pfs = VTOPFS(dvp); |
| 743 | switch (pfs->pfs_type) { |
| 744 | case Proot: |
| 745 | if (cnp->cn_flags & CNP_ISDOTDOT) |
| 746 | return (EIO); |
| 747 | |
| 748 | if (CNEQ(cnp, "curproc", 7)) { |
| 749 | error = procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc); |
| 750 | goto out; |
| 751 | } |
| 752 | |
| 753 | pid = atopid(pname, cnp->cn_namelen); |
| 754 | if (pid == NO_PID) |
| 755 | break; |
| 756 | |
| 757 | p = pfs_pfind(pid); |
| 758 | if (p == NULL) |
| 759 | break; |
| 760 | |
| 761 | if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred)) |
| 762 | break; |
| 763 | |
| 764 | if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 && |
| 765 | ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid) |
| 766 | break; |
| 767 | |
| 768 | error = procfs_allocvp(dvp->v_mount, vpp, pid, Pproc); |
| 769 | goto out; |
| 770 | |
| 771 | case Pproc: |
| 772 | if (cnp->cn_flags & CNP_ISDOTDOT) { |
| 773 | error = procfs_root(dvp->v_mount, vpp); |
| 774 | goto out; |
| 775 | } |
| 776 | |
| 777 | p = pfs_pfind(pfs->pfs_pid); |
| 778 | if (p == NULL) |
| 779 | break; |
| 780 | /* XXX lwp */ |
| 781 | lp = FIRST_LWP_IN_PROC(p); |
| 782 | |
| 783 | if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred)) |
| 784 | break; |
| 785 | |
| 786 | if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 && |
| 787 | ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid) |
| 788 | break; |
| 789 | |
| 790 | for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) { |
| 791 | if (cnp->cn_namelen == pt->pt_namlen && |
| 792 | bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 && |
| 793 | (pt->pt_valid == NULL || (*pt->pt_valid)(lp))) |
| 794 | goto found; |
| 795 | } |
| 796 | break; |
| 797 | found: |
| 798 | error = procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid, |
| 799 | pt->pt_pfstype); |
| 800 | goto out; |
| 801 | |
| 802 | default: |
| 803 | error = ENOTDIR; |
| 804 | goto out; |
| 805 | } |
| 806 | if (cnp->cn_nameiop == NAMEI_LOOKUP) |
| 807 | error = ENOENT; |
| 808 | else |
| 809 | error = EROFS; |
| 810 | /* |
| 811 | * If no error occured *vpp will hold a referenced locked vnode. |
| 812 | * dvp was passed to us locked and *vpp must be returned locked. |
| 813 | * If *vpp != dvp then we should unlock dvp if (1) this is not the |
| 814 | * last component or (2) CNP_LOCKPARENT is not set. |
| 815 | */ |
| 816 | out: |
| 817 | if (error == 0 && *vpp != dvp) { |
| 818 | if ((cnp->cn_flags & CNP_LOCKPARENT) == 0) { |
| 819 | cnp->cn_flags |= CNP_PDIRUNLOCK; |
| 820 | vn_unlock(dvp); |
| 821 | } |
| 822 | } |
| 823 | if (p) |
| 824 | PRELE(p); |
| 825 | return (error); |
| 826 | } |
| 827 | |
| 828 | /* |
| 829 | * Does this process have a text file? |
| 830 | */ |
| 831 | int |
| 832 | procfs_validfile(struct lwp *lp) |
| 833 | { |
| 834 | return (procfs_findtextvp(lp->lwp_proc) != NULLVP); |
| 835 | } |
| 836 | |
| 837 | /* |
| 838 | * readdir() returns directory entries from pfsnode (vp). |
| 839 | * |
| 840 | * We generate just one directory entry at a time, as it would probably |
| 841 | * not pay off to buffer several entries locally to save uiomove calls. |
| 842 | * |
| 843 | * procfs_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred, |
| 844 | * int *a_eofflag, int *a_ncookies, off_t **a_cookies) |
| 845 | */ |
| 846 | static int |
| 847 | procfs_readdir(struct vop_readdir_args *ap) |
| 848 | { |
| 849 | struct pfsnode *pfs; |
| 850 | int error; |
| 851 | |
| 852 | if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX) |
| 853 | return (EINVAL); |
| 854 | if ((error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY)) != 0) |
| 855 | return (error); |
| 856 | pfs = VTOPFS(ap->a_vp); |
| 857 | |
| 858 | switch (pfs->pfs_type) { |
| 859 | case Pproc: |
| 860 | /* |
| 861 | * this is for the process-specific sub-directories. |
| 862 | * all that is needed to is copy out all the entries |
| 863 | * from the procent[] table (top of this file). |
| 864 | */ |
| 865 | error = procfs_readdir_proc(ap); |
| 866 | break; |
| 867 | case Proot: |
| 868 | /* |
| 869 | * this is for the root of the procfs filesystem |
| 870 | * what is needed is a special entry for "curproc" |
| 871 | * followed by an entry for each process on allproc |
| 872 | */ |
| 873 | error = procfs_readdir_root(ap); |
| 874 | break; |
| 875 | default: |
| 876 | error = ENOTDIR; |
| 877 | break; |
| 878 | } |
| 879 | |
| 880 | vn_unlock(ap->a_vp); |
| 881 | return (error); |
| 882 | } |
| 883 | |
| 884 | static int |
| 885 | procfs_readdir_proc(struct vop_readdir_args *ap) |
| 886 | { |
| 887 | struct pfsnode *pfs; |
| 888 | int error, i, retval; |
| 889 | struct proc *p; |
| 890 | struct lwp *lp; |
| 891 | struct proc_target *pt; |
| 892 | struct uio *uio = ap->a_uio; |
| 893 | |
| 894 | pfs = VTOPFS(ap->a_vp); |
| 895 | p = pfs_pfind(pfs->pfs_pid); |
| 896 | if (p == NULL) |
| 897 | return(0); |
| 898 | if (!PRISON_CHECK(ap->a_cred, p->p_ucred)) { |
| 899 | error = 0; |
| 900 | goto done; |
| 901 | } |
| 902 | /* XXX lwp, not MPSAFE */ |
| 903 | lp = FIRST_LWP_IN_PROC(p); |
| 904 | |
| 905 | error = 0; |
| 906 | i = (int)uio->uio_offset; |
| 907 | if (i < 0) { |
| 908 | error = EINVAL; |
| 909 | goto done; |
| 910 | } |
| 911 | |
| 912 | for (pt = &proc_targets[i]; |
| 913 | !error && uio->uio_resid > 0 && i < nproc_targets; pt++, i++) { |
| 914 | if (pt->pt_valid && (*pt->pt_valid)(lp) == 0) |
| 915 | continue; |
| 916 | |
| 917 | retval = vop_write_dirent(&error, uio, |
| 918 | PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype), pt->pt_type, |
| 919 | pt->pt_namlen, pt->pt_name); |
| 920 | if (retval) |
| 921 | break; |
| 922 | } |
| 923 | |
| 924 | uio->uio_offset = (off_t)i; |
| 925 | error = 0; |
| 926 | done: |
| 927 | PRELE(p); |
| 928 | return error; |
| 929 | } |
| 930 | |
| 931 | struct procfs_readdir_root_info { |
| 932 | int error; |
| 933 | int i; |
| 934 | int pcnt; |
| 935 | struct uio *uio; |
| 936 | struct ucred *cred; |
| 937 | }; |
| 938 | |
| 939 | static int procfs_readdir_root_callback(struct proc *p, void *data); |
| 940 | |
| 941 | static int |
| 942 | procfs_readdir_root(struct vop_readdir_args *ap) |
| 943 | { |
| 944 | struct procfs_readdir_root_info info; |
| 945 | struct uio *uio = ap->a_uio; |
| 946 | int res; |
| 947 | |
| 948 | info.error = 0; |
| 949 | info.i = (int)uio->uio_offset; |
| 950 | |
| 951 | if (info.i < 0) |
| 952 | return (EINVAL); |
| 953 | |
| 954 | info.pcnt = 0; |
| 955 | info.uio = uio; |
| 956 | info.cred = ap->a_cred; |
| 957 | while (info.pcnt < 3) { |
| 958 | res = procfs_readdir_root_callback(NULL, &info); |
| 959 | if (res < 0) |
| 960 | break; |
| 961 | } |
| 962 | if (res >= 0) |
| 963 | allproc_scan(procfs_readdir_root_callback, &info); |
| 964 | uio->uio_offset = (off_t)info.i; |
| 965 | |
| 966 | return (info.error); |
| 967 | } |
| 968 | |
| 969 | static int |
| 970 | procfs_readdir_root_callback(struct proc *p, void *data) |
| 971 | { |
| 972 | struct procfs_readdir_root_info *info = data; |
| 973 | struct uio *uio; |
| 974 | int retval; |
| 975 | ino_t d_ino; |
| 976 | const char *d_name; |
| 977 | char d_name_pid[20]; |
| 978 | size_t d_namlen; |
| 979 | uint8_t d_type; |
| 980 | |
| 981 | uio = info->uio; |
| 982 | |
| 983 | if (uio->uio_resid <= 0 || info->error) |
| 984 | return(-1); |
| 985 | |
| 986 | switch (info->pcnt) { |
| 987 | case 0: /* `.' */ |
| 988 | d_ino = PROCFS_FILENO(0, Proot); |
| 989 | d_name = "."; |
| 990 | d_namlen = 1; |
| 991 | d_type = DT_DIR; |
| 992 | break; |
| 993 | case 1: /* `..' */ |
| 994 | d_ino = PROCFS_FILENO(0, Proot); |
| 995 | d_name = ".."; |
| 996 | d_namlen = 2; |
| 997 | d_type = DT_DIR; |
| 998 | break; |
| 999 | |
| 1000 | case 2: |
| 1001 | d_ino = PROCFS_FILENO(0, Pcurproc); |
| 1002 | d_namlen = 7; |
| 1003 | d_name = "curproc"; |
| 1004 | d_type = DT_LNK; |
| 1005 | break; |
| 1006 | |
| 1007 | |
| 1008 | default: |
| 1009 | if (!PRISON_CHECK(info->cred, p->p_ucred)) |
| 1010 | return(0); |
| 1011 | if (ps_showallprocs == 0 && |
| 1012 | info->cred->cr_uid != 0 && |
| 1013 | info->cred->cr_uid != p->p_ucred->cr_uid) { |
| 1014 | return(0); |
| 1015 | } |
| 1016 | |
| 1017 | /* |
| 1018 | * Skip entries we have already returned (optimization) |
| 1019 | */ |
| 1020 | if (info->pcnt < info->i) { |
| 1021 | ++info->pcnt; |
| 1022 | return(0); |
| 1023 | } |
| 1024 | |
| 1025 | d_ino = PROCFS_FILENO(p->p_pid, Pproc); |
| 1026 | d_namlen = ksnprintf(d_name_pid, sizeof(d_name_pid), |
| 1027 | "%ld", (long)p->p_pid); |
| 1028 | d_name = d_name_pid; |
| 1029 | d_type = DT_DIR; |
| 1030 | break; |
| 1031 | } |
| 1032 | |
| 1033 | /* |
| 1034 | * Skip entries we have already returned (optimization) |
| 1035 | */ |
| 1036 | if (info->pcnt < info->i) { |
| 1037 | ++info->pcnt; |
| 1038 | return(0); |
| 1039 | } |
| 1040 | |
| 1041 | retval = vop_write_dirent(&info->error, uio, |
| 1042 | d_ino, d_type, d_namlen, d_name); |
| 1043 | if (retval) |
| 1044 | return(-1); |
| 1045 | ++info->pcnt; |
| 1046 | ++info->i; |
| 1047 | return(0); |
| 1048 | } |
| 1049 | |
| 1050 | /* |
| 1051 | * readlink reads the link of `curproc' or `file' |
| 1052 | */ |
| 1053 | static int |
| 1054 | procfs_readlink(struct vop_readlink_args *ap) |
| 1055 | { |
| 1056 | char buf[16]; /* should be enough */ |
| 1057 | struct proc *procp; |
| 1058 | struct vnode *vp = ap->a_vp; |
| 1059 | struct pfsnode *pfs = VTOPFS(vp); |
| 1060 | char *fullpath, *freepath; |
| 1061 | int error, len; |
| 1062 | |
| 1063 | switch (pfs->pfs_type) { |
| 1064 | case Pcurproc: |
| 1065 | if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc)) |
| 1066 | return (EINVAL); |
| 1067 | |
| 1068 | len = ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); |
| 1069 | |
| 1070 | return (uiomove(buf, len, ap->a_uio)); |
| 1071 | /* |
| 1072 | * There _should_ be no way for an entire process to disappear |
| 1073 | * from under us... |
| 1074 | */ |
| 1075 | case Pfile: |
| 1076 | procp = pfs_pfind(pfs->pfs_pid); |
| 1077 | if (procp == NULL || procp->p_ucred == NULL) { |
| 1078 | kprintf("procfs_readlink: pid %d disappeared\n", |
| 1079 | pfs->pfs_pid); |
| 1080 | if (procp) |
| 1081 | PRELE(procp); |
| 1082 | return (uiomove("unknown", sizeof("unknown") - 1, |
| 1083 | ap->a_uio)); |
| 1084 | } |
| 1085 | error = cache_fullpath(procp, &procp->p_textnch, &fullpath, &freepath, 0); |
| 1086 | if (error != 0) { |
| 1087 | if (procp) |
| 1088 | PRELE(procp); |
| 1089 | return (uiomove("unknown", sizeof("unknown") - 1, |
| 1090 | ap->a_uio)); |
| 1091 | } |
| 1092 | error = uiomove(fullpath, strlen(fullpath), ap->a_uio); |
| 1093 | kfree(freepath, M_TEMP); |
| 1094 | if (procp) |
| 1095 | PRELE(procp); |
| 1096 | return (error); |
| 1097 | default: |
| 1098 | return (EINVAL); |
| 1099 | } |
| 1100 | } |
| 1101 | |
| 1102 | /* |
| 1103 | * convert decimal ascii to pid_t |
| 1104 | */ |
| 1105 | static pid_t |
| 1106 | atopid(const char *b, u_int len) |
| 1107 | { |
| 1108 | pid_t p = 0; |
| 1109 | |
| 1110 | while (len--) { |
| 1111 | char c = *b++; |
| 1112 | if (c < '0' || c > '9') |
| 1113 | return (NO_PID); |
| 1114 | p = 10 * p + (c - '0'); |
| 1115 | if (p > PID_MAX) |
| 1116 | return (NO_PID); |
| 1117 | } |
| 1118 | |
| 1119 | return (p); |
| 1120 | } |
| 1121 | |