procfs_subr.c revision 1.42
1 /* $NetBSD: procfs_subr.c,v 1.42 2003/01/03 13:21:18 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1994 Christopher G. Demetriou. All rights reserved. 5 * Copyright (c) 1993 Jan-Simon Pendry 6 * Copyright (c) 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * Jan-Simon Pendry. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: procfs_subr.c,v 1.42 2003/01/03 13:21:18 christos Exp $"); 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/proc.h> 51 #include <sys/vnode.h> 52 #include <sys/malloc.h> 53 #include <sys/stat.h> 54 #include <sys/file.h> 55 #include <sys/filedesc.h> 56 57 #include <miscfs/procfs/procfs.h> 58 59 void procfs_hashins __P((struct pfsnode *)); 60 void procfs_hashrem __P((struct pfsnode *)); 61 struct vnode *procfs_hashget __P((pid_t, pfstype, int, struct mount *)); 62 63 LIST_HEAD(pfs_hashhead, pfsnode) *pfs_hashtbl; 64 u_long pfs_ihash; /* size of hash table - 1 */ 65 #define PFSPIDHASH(pid) ((pid) & pfs_ihash) 66 67 struct lock pfs_hashlock; 68 struct simplelock pfs_hash_slock; 69 70 #define ISSET(t, f) ((t) & (f)) 71 72 /* 73 * allocate a pfsnode/vnode pair. the vnode is 74 * referenced, and locked. 75 * 76 * the pid, pfs_type, and mount point uniquely 77 * identify a pfsnode. the mount point is needed 78 * because someone might mount this filesystem 79 * twice. 80 * 81 * all pfsnodes are maintained on a singly-linked 82 * list. new nodes are only allocated when they cannot 83 * be found on this list. entries on the list are 84 * removed when the vfs reclaim entry is called. 85 * 86 * a single lock is kept for the entire list. this is 87 * needed because the getnewvnode() function can block 88 * waiting for a vnode to become free, in which case there 89 * may be more than one process trying to get the same 90 * vnode. this lock is only taken if we are going to 91 * call getnewvnode, since the kernel itself is single-threaded. 92 * 93 * if an entry is found on the list, then call vget() to 94 * take a reference. this is done because there may be 95 * zero references to it and so it needs to removed from 96 * the vnode free list. 97 */ 98 int 99 procfs_allocvp(mp, vpp, pid, pfs_type, fd) 100 struct mount *mp; 101 struct vnode **vpp; 102 pid_t pid; 103 pfstype pfs_type; 104 int fd; 105 { 106 struct pfsnode *pfs; 107 struct vnode *vp; 108 int error; 109 110 do { 111 if ((*vpp = procfs_hashget(pid, pfs_type, fd, mp)) != NULL) 112 return (0); 113 } while (lockmgr(&pfs_hashlock, LK_EXCLUSIVE|LK_SLEEPFAIL, 0)); 114 115 if ((error = getnewvnode(VT_PROCFS, mp, procfs_vnodeop_p, vpp)) != 0) { 116 *vpp = NULL; 117 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 118 return (error); 119 } 120 vp = *vpp; 121 122 MALLOC(pfs, void *, sizeof(struct pfsnode), M_TEMP, M_WAITOK); 123 vp->v_data = pfs; 124 125 pfs->pfs_pid = pid; 126 pfs->pfs_type = pfs_type; 127 pfs->pfs_vnode = vp; 128 pfs->pfs_flags = 0; 129 pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type, fd); 130 pfs->pfs_fd = fd; 131 132 switch (pfs_type) { 133 case Proot: /* /proc = dr-xr-xr-x */ 134 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 135 vp->v_type = VDIR; 136 vp->v_flag = VROOT; 137 break; 138 139 case Pcurproc: /* /proc/curproc = lr-xr-xr-x */ 140 case Pself: /* /proc/self = lr-xr-xr-x */ 141 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 142 vp->v_type = VLNK; 143 break; 144 145 case Pproc: /* /proc/N = dr-xr-xr-x */ 146 case Pfd: 147 if (fd == -1) { /* /proc/N/fd = dr-xr-xr-x */ 148 pfs->pfs_mode = 149 S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 150 vp->v_type = VDIR; 151 } else { /* /proc/N/fd/M = [ps-]rw------- */ 152 struct file *fp; 153 struct vnode *vxp; 154 if ((error = procfs_getfp(pfs, &fp)) != 0) 155 return error; 156 pfs->pfs_mode = S_IRUSR|S_IWUSR; 157 switch (fp->f_type) { 158 case DTYPE_VNODE: 159 vxp = (struct vnode *)fp->f_data; 160 vp->v_type = vxp->v_type; 161 break; 162 case DTYPE_PIPE: 163 vp->v_type = VFIFO; 164 break; 165 case DTYPE_SOCKET: 166 vp->v_type = VSOCK; 167 break; 168 case DTYPE_KQUEUE: 169 case DTYPE_MISC: 170 return EOPNOTSUPP; 171 default: 172 panic("unknown file type %d\n", fp->f_type); 173 } 174 } 175 break; 176 177 case Pfile: /* /proc/N/file = -rw------- */ 178 case Pmem: /* /proc/N/mem = -rw------- */ 179 case Pregs: /* /proc/N/regs = -rw------- */ 180 case Pfpregs: /* /proc/N/fpregs = -rw------- */ 181 pfs->pfs_mode = S_IRUSR|S_IWUSR; 182 vp->v_type = VREG; 183 break; 184 185 case Pctl: /* /proc/N/ctl = --w------ */ 186 case Pnote: /* /proc/N/note = --w------ */ 187 case Pnotepg: /* /proc/N/notepg = --w------ */ 188 pfs->pfs_mode = S_IWUSR; 189 vp->v_type = VREG; 190 break; 191 192 case Pmap: /* /proc/N/map = -r--r--r-- */ 193 case Pmaps: /* /proc/N/maps = -r--r--r-- */ 194 case Pstatus: /* /proc/N/status = -r--r--r-- */ 195 case Pcmdline: /* /proc/N/cmdline = -r--r--r-- */ 196 case Pmeminfo: /* /proc/meminfo = -r--r--r-- */ 197 case Pcpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 198 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 199 vp->v_type = VREG; 200 break; 201 202 #ifdef __HAVE_PROCFS_MACHDEP 203 PROCFS_MACHDEP_NODETYPE_CASES 204 procfs_machdep_allocvp(vp); 205 break; 206 #endif 207 208 default: 209 panic("procfs_allocvp"); 210 } 211 212 procfs_hashins(pfs); 213 uvm_vnp_setsize(vp, 0); 214 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 215 216 return (error); 217 } 218 219 int 220 procfs_freevp(vp) 221 struct vnode *vp; 222 { 223 struct pfsnode *pfs = VTOPFS(vp); 224 225 procfs_hashrem(pfs); 226 227 FREE(vp->v_data, M_TEMP); 228 vp->v_data = 0; 229 return (0); 230 } 231 232 int 233 procfs_rw(v) 234 void *v; 235 { 236 struct vop_read_args *ap = v; 237 struct vnode *vp = ap->a_vp; 238 struct uio *uio = ap->a_uio; 239 struct proc *curp = uio->uio_procp; 240 struct pfsnode *pfs = VTOPFS(vp); 241 struct proc *p; 242 243 p = PFIND(pfs->pfs_pid); 244 if (p == 0) 245 return (EINVAL); 246 247 switch (pfs->pfs_type) { 248 case Pregs: 249 case Pfpregs: 250 case Pmem: 251 #if defined(__HAVE_PROCFS_MACHDEP) && defined(PROCFS_MACHDEP_PROTECT_CASES) 252 PROCFS_MACHDEP_PROTECT_CASES 253 #endif 254 /* 255 * Do not allow init to be modified while in secure mode; it 256 * could be duped into changing the security level. 257 */ 258 if (uio->uio_rw == UIO_WRITE && 259 p == initproc && securelevel > -1) 260 return (EPERM); 261 break; 262 263 default: 264 break; 265 } 266 267 switch (pfs->pfs_type) { 268 case Pnote: 269 case Pnotepg: 270 return (procfs_donote(curp, p, pfs, uio)); 271 272 case Pregs: 273 return (procfs_doregs(curp, p, pfs, uio)); 274 275 case Pfpregs: 276 return (procfs_dofpregs(curp, p, pfs, uio)); 277 278 case Pctl: 279 return (procfs_doctl(curp, p, pfs, uio)); 280 281 case Pstatus: 282 return (procfs_dostatus(curp, p, pfs, uio)); 283 284 case Pmap: 285 return (procfs_domap(curp, p, pfs, uio, 0)); 286 287 case Pmaps: 288 return (procfs_domap(curp, p, pfs, uio, 1)); 289 290 case Pmem: 291 return (procfs_domem(curp, p, pfs, uio)); 292 293 case Pcmdline: 294 return (procfs_docmdline(curp, p, pfs, uio)); 295 296 case Pmeminfo: 297 return (procfs_domeminfo(curp, p, pfs, uio)); 298 299 case Pcpuinfo: 300 return (procfs_docpuinfo(curp, p, pfs, uio)); 301 302 case Pfd: 303 return (procfs_dofd(curp, p, pfs, uio)); 304 305 #ifdef __HAVE_PROCFS_MACHDEP 306 PROCFS_MACHDEP_NODETYPE_CASES 307 return (procfs_machdep_rw(curp, p, pfs, uio)); 308 #endif 309 310 default: 311 return (EOPNOTSUPP); 312 } 313 } 314 315 /* 316 * Get a string from userland into (buf). Strip a trailing 317 * nl character (to allow easy access from the shell). 318 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 319 * will automatically add a nul char at the end. 320 * 321 * Returns 0 on success or the following errors 322 * 323 * EINVAL: file offset is non-zero. 324 * EMSGSIZE: message is longer than kernel buffer 325 * EFAULT: user i/o buffer is not addressable 326 */ 327 int 328 vfs_getuserstr(uio, buf, buflenp) 329 struct uio *uio; 330 char *buf; 331 int *buflenp; 332 { 333 int xlen; 334 int error; 335 336 if (uio->uio_offset != 0) 337 return (EINVAL); 338 339 xlen = *buflenp; 340 341 /* must be able to read the whole string in one go */ 342 if (xlen < uio->uio_resid) 343 return (EMSGSIZE); 344 xlen = uio->uio_resid; 345 346 if ((error = uiomove(buf, xlen, uio)) != 0) 347 return (error); 348 349 /* allow multiple writes without seeks */ 350 uio->uio_offset = 0; 351 352 /* cleanup string and remove trailing newline */ 353 buf[xlen] = '\0'; 354 xlen = strlen(buf); 355 if (xlen > 0 && buf[xlen-1] == '\n') 356 buf[--xlen] = '\0'; 357 *buflenp = xlen; 358 359 return (0); 360 } 361 362 const vfs_namemap_t * 363 vfs_findname(nm, buf, buflen) 364 const vfs_namemap_t *nm; 365 const char *buf; 366 int buflen; 367 { 368 369 for (; nm->nm_name; nm++) 370 if (memcmp(buf, nm->nm_name, buflen+1) == 0) 371 return (nm); 372 373 return (0); 374 } 375 376 /* 377 * Initialize pfsnode hash table. 378 */ 379 void 380 procfs_hashinit() 381 { 382 lockinit(&pfs_hashlock, PINOD, "pfs_hashlock", 0, 0); 383 pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, 384 M_WAITOK, &pfs_ihash); 385 simple_lock_init(&pfs_hash_slock); 386 } 387 388 void 389 procfs_hashreinit() 390 { 391 struct pfsnode *pp; 392 struct pfs_hashhead *oldhash, *hash; 393 u_long i, oldmask, mask, val; 394 395 hash = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK, 396 &mask); 397 398 simple_lock(&pfs_hash_slock); 399 oldhash = pfs_hashtbl; 400 oldmask = pfs_ihash; 401 pfs_hashtbl = hash; 402 pfs_ihash = mask; 403 for (i = 0; i <= oldmask; i++) { 404 while ((pp = LIST_FIRST(&oldhash[i])) != NULL) { 405 LIST_REMOVE(pp, pfs_hash); 406 val = PFSPIDHASH(pp->pfs_pid); 407 LIST_INSERT_HEAD(&hash[val], pp, pfs_hash); 408 } 409 } 410 simple_unlock(&pfs_hash_slock); 411 hashdone(oldhash, M_UFSMNT); 412 } 413 414 /* 415 * Free pfsnode hash table. 416 */ 417 void 418 procfs_hashdone() 419 { 420 hashdone(pfs_hashtbl, M_UFSMNT); 421 } 422 423 struct vnode * 424 procfs_hashget(pid, type, fd, mp) 425 pid_t pid; 426 pfstype type; 427 int fd; 428 struct mount *mp; 429 { 430 struct pfs_hashhead *ppp; 431 struct pfsnode *pp; 432 struct vnode *vp; 433 434 loop: 435 simple_lock(&pfs_hash_slock); 436 ppp = &pfs_hashtbl[PFSPIDHASH(pid)]; 437 LIST_FOREACH(pp, ppp, pfs_hash) { 438 vp = PFSTOV(pp); 439 if (pid == pp->pfs_pid && pp->pfs_type == type && 440 pp->pfs_fd == fd && vp->v_mount == mp) { 441 simple_lock(&vp->v_interlock); 442 simple_unlock(&pfs_hash_slock); 443 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) 444 goto loop; 445 return (vp); 446 } 447 } 448 simple_unlock(&pfs_hash_slock); 449 return (NULL); 450 } 451 452 /* 453 * Insert the pfsnode into the hash table and lock it. 454 */ 455 void 456 procfs_hashins(pp) 457 struct pfsnode *pp; 458 { 459 struct pfs_hashhead *ppp; 460 461 /* lock the pfsnode, then put it on the appropriate hash list */ 462 lockmgr(&pp->pfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0); 463 464 simple_lock(&pfs_hash_slock); 465 ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)]; 466 LIST_INSERT_HEAD(ppp, pp, pfs_hash); 467 simple_unlock(&pfs_hash_slock); 468 } 469 470 /* 471 * Remove the pfsnode from the hash table. 472 */ 473 void 474 procfs_hashrem(pp) 475 struct pfsnode *pp; 476 { 477 simple_lock(&pfs_hash_slock); 478 LIST_REMOVE(pp, pfs_hash); 479 simple_unlock(&pfs_hash_slock); 480 } 481 482 void 483 procfs_revoke_vnodes(p, arg) 484 struct proc *p; 485 void *arg; 486 { 487 struct pfsnode *pfs, *pnext; 488 struct vnode *vp; 489 struct mount *mp = (struct mount *)arg; 490 struct pfs_hashhead *ppp; 491 492 if (!(p->p_flag & P_SUGID)) 493 return; 494 495 ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)]; 496 for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) { 497 vp = PFSTOV(pfs); 498 pnext = LIST_NEXT(pfs, pfs_hash); 499 if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid && 500 vp->v_mount == mp) 501 VOP_REVOKE(vp, REVOKEALL); 502 } 503 } 504 505 int 506 procfs_getfp(pfs, fp) 507 struct pfsnode *pfs; 508 struct file **fp; 509 { 510 struct proc *p = PFIND(pfs->pfs_pid); 511 512 if (p == NULL) 513 return ESRCH; 514 515 if (pfs->pfs_fd == -1) 516 return EINVAL; 517 518 if ((*fp = p->p_fd->fd_ofiles[pfs->pfs_fd]) == NULL) 519 return EBADF; 520 return 0; 521 } 522
Indexes created Sun Sep 21 20:09:37 GMT 2025