procfs_subr.c revision 1.36.2.1
1 /* $NetBSD: procfs_subr.c,v 1.36.2.1 2001/03/05 22:49:51 nathanw 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/param.h> 44 #include <sys/systm.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/proc.h> 48 #include <sys/vnode.h> 49 #include <sys/malloc.h> 50 #include <sys/stat.h> 51 52 #include <miscfs/procfs/procfs.h> 53 54 void procfs_hashins __P((struct pfsnode *)); 55 void procfs_hashrem __P((struct pfsnode *)); 56 struct vnode *procfs_hashget __P((pid_t, pfstype, struct mount *)); 57 58 LIST_HEAD(pfs_hashhead, pfsnode) *pfs_hashtbl; 59 u_long pfs_ihash; /* size of hash table - 1 */ 60 #define PFSPIDHASH(pid) (&pfs_hashtbl[(pid) & pfs_ihash]) 61 62 struct lock pfs_hashlock; 63 struct simplelock pfs_hash_slock; 64 65 #define ISSET(t, f) ((t) & (f)) 66 67 /* 68 * allocate a pfsnode/vnode pair. the vnode is 69 * referenced, and locked. 70 * 71 * the pid, pfs_type, and mount point uniquely 72 * identify a pfsnode. the mount point is needed 73 * because someone might mount this filesystem 74 * twice. 75 * 76 * all pfsnodes are maintained on a singly-linked 77 * list. new nodes are only allocated when they cannot 78 * be found on this list. entries on the list are 79 * removed when the vfs reclaim entry is called. 80 * 81 * a single lock is kept for the entire list. this is 82 * needed because the getnewvnode() function can block 83 * waiting for a vnode to become free, in which case there 84 * may be more than one process trying to get the same 85 * vnode. this lock is only taken if we are going to 86 * call getnewvnode, since the kernel itself is single-threaded. 87 * 88 * if an entry is found on the list, then call vget() to 89 * take a reference. this is done because there may be 90 * zero references to it and so it needs to removed from 91 * the vnode free list. 92 */ 93 int 94 procfs_allocvp(mp, vpp, pid, pfs_type) 95 struct mount *mp; 96 struct vnode **vpp; 97 long pid; 98 pfstype pfs_type; 99 { 100 struct pfsnode *pfs; 101 struct vnode *vp; 102 int error; 103 104 do { 105 if ((*vpp = procfs_hashget(pid, pfs_type, mp)) != NULL) 106 return (0); 107 } while (lockmgr(&pfs_hashlock, LK_EXCLUSIVE|LK_SLEEPFAIL, 0)); 108 109 if ((error = getnewvnode(VT_PROCFS, mp, procfs_vnodeop_p, vpp)) != 0) { 110 *vpp = NULL; 111 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 112 return (error); 113 } 114 vp = *vpp; 115 116 MALLOC(pfs, void *, sizeof(struct pfsnode), M_TEMP, M_WAITOK); 117 vp->v_data = pfs; 118 119 pfs->pfs_pid = (pid_t) pid; 120 pfs->pfs_type = pfs_type; 121 pfs->pfs_vnode = vp; 122 pfs->pfs_flags = 0; 123 pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type); 124 125 switch (pfs_type) { 126 case Proot: /* /proc = dr-xr-xr-x */ 127 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 128 vp->v_type = VDIR; 129 vp->v_flag = VROOT; 130 break; 131 132 case Pcurproc: /* /proc/curproc = lr-xr-xr-x */ 133 case Pself: /* /proc/self = lr-xr-xr-x */ 134 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 135 vp->v_type = VLNK; 136 break; 137 138 case Pproc: /* /proc/N = dr-xr-xr-x */ 139 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 140 vp->v_type = VDIR; 141 break; 142 143 case Pfile: /* /proc/N/file = -rw------- */ 144 case Pmem: /* /proc/N/mem = -rw------- */ 145 case Pregs: /* /proc/N/regs = -rw------- */ 146 case Pfpregs: /* /proc/N/fpregs = -rw------- */ 147 pfs->pfs_mode = S_IRUSR|S_IWUSR; 148 vp->v_type = VREG; 149 break; 150 151 case Pctl: /* /proc/N/ctl = --w------ */ 152 case Pnote: /* /proc/N/note = --w------ */ 153 case Pnotepg: /* /proc/N/notepg = --w------ */ 154 pfs->pfs_mode = S_IWUSR; 155 vp->v_type = VREG; 156 break; 157 158 case Pmap: /* /proc/N/map = -r--r--r-- */ 159 case Pstatus: /* /proc/N/status = -r--r--r-- */ 160 case Pcmdline: /* /proc/N/cmdline = -r--r--r-- */ 161 case Pmeminfo: /* /proc/meminfo = -r--r--r-- */ 162 case Pcpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 163 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 164 vp->v_type = VREG; 165 break; 166 167 default: 168 panic("procfs_allocvp"); 169 } 170 171 procfs_hashins(pfs); 172 uvm_vnp_setsize(vp, 0); 173 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 174 175 return (error); 176 } 177 178 int 179 procfs_freevp(vp) 180 struct vnode *vp; 181 { 182 struct pfsnode *pfs = VTOPFS(vp); 183 184 procfs_hashrem(pfs); 185 186 FREE(vp->v_data, M_TEMP); 187 vp->v_data = 0; 188 return (0); 189 } 190 191 int 192 procfs_rw(v) 193 void *v; 194 { 195 struct vop_read_args *ap = v; 196 struct vnode *vp = ap->a_vp; 197 struct uio *uio = ap->a_uio; 198 struct proc *curp = uio->uio_procp; 199 struct pfsnode *pfs = VTOPFS(vp); 200 struct lwp *l; 201 struct proc *p; 202 203 p = PFIND(pfs->pfs_pid); 204 if (p == 0) 205 return (EINVAL); 206 207 /* XXX NJWLWP 208 * The entire procfs interface needs work to be useful to 209 * a process with multiple LWPs. For the moment, we'll 210 * just kluge this and fail on others. 211 */ 212 213 if (p->p_nlwps > 1) 214 switch (pfs->pfs_type) { 215 case Pnote: 216 case Pnotepg: 217 case Pstatus: 218 case Pmap: 219 case Pmem: 220 case Pcmdline: 221 break; 222 case Pregs: 223 case Pfpregs: 224 case Pctl: 225 default: 226 return (EOPNOTSUPP); 227 } 228 229 l = LIST_FIRST(&p->p_lwps); 230 231 switch (pfs->pfs_type) { 232 case Pregs: 233 case Pfpregs: 234 case Pmem: 235 /* 236 * Do not allow init to be modified while in secure mode; it 237 * could be duped into changing the security level. 238 */ 239 if (uio->uio_rw == UIO_WRITE && 240 p == initproc && securelevel > -1) 241 return (EPERM); 242 break; 243 244 default: 245 break; 246 } 247 248 switch (pfs->pfs_type) { 249 case Pnote: 250 case Pnotepg: 251 return (procfs_donote(curp, p, pfs, uio)); 252 253 case Pregs: 254 return (procfs_doregs(curp, l, pfs, uio)); 255 256 case Pfpregs: 257 return (procfs_dofpregs(curp, l, pfs, uio)); 258 259 case Pctl: 260 return (procfs_doctl(curp, l, pfs, uio)); 261 262 case Pstatus: 263 return (procfs_dostatus(curp, l, pfs, uio)); 264 265 case Pmap: 266 return (procfs_domap(curp, p, pfs, uio)); 267 268 case Pmem: 269 return (procfs_domem(curp, l, pfs, uio)); 270 271 case Pcmdline: 272 return (procfs_docmdline(curp, p, pfs, uio)); 273 274 case Pmeminfo: 275 return (procfs_domeminfo(curp, p, pfs, uio)); 276 case Pcpuinfo: 277 return (procfs_docpuinfo(curp, p, pfs, uio)); 278 279 default: 280 return (EOPNOTSUPP); 281 } 282 } 283 284 /* 285 * Get a string from userland into (buf). Strip a trailing 286 * nl character (to allow easy access from the shell). 287 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 288 * will automatically add a nul char at the end. 289 * 290 * Returns 0 on success or the following errors 291 * 292 * EINVAL: file offset is non-zero. 293 * EMSGSIZE: message is longer than kernel buffer 294 * EFAULT: user i/o buffer is not addressable 295 */ 296 int 297 vfs_getuserstr(uio, buf, buflenp) 298 struct uio *uio; 299 char *buf; 300 int *buflenp; 301 { 302 int xlen; 303 int error; 304 305 if (uio->uio_offset != 0) 306 return (EINVAL); 307 308 xlen = *buflenp; 309 310 /* must be able to read the whole string in one go */ 311 if (xlen < uio->uio_resid) 312 return (EMSGSIZE); 313 xlen = uio->uio_resid; 314 315 if ((error = uiomove(buf, xlen, uio)) != 0) 316 return (error); 317 318 /* allow multiple writes without seeks */ 319 uio->uio_offset = 0; 320 321 /* cleanup string and remove trailing newline */ 322 buf[xlen] = '\0'; 323 xlen = strlen(buf); 324 if (xlen > 0 && buf[xlen-1] == '\n') 325 buf[--xlen] = '\0'; 326 *buflenp = xlen; 327 328 return (0); 329 } 330 331 const vfs_namemap_t * 332 vfs_findname(nm, buf, buflen) 333 const vfs_namemap_t *nm; 334 const char *buf; 335 int buflen; 336 { 337 338 for (; nm->nm_name; nm++) 339 if (memcmp(buf, nm->nm_name, buflen+1) == 0) 340 return (nm); 341 342 return (0); 343 } 344 345 /* 346 * Initialize pfsnode hash table. 347 */ 348 void 349 procfs_hashinit() 350 { 351 lockinit(&pfs_hashlock, PINOD, "pfs_hashlock", 0, 0); 352 pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, 353 M_WAITOK, &pfs_ihash); 354 simple_lock_init(&pfs_hash_slock); 355 } 356 357 /* 358 * Free pfsnode hash table. 359 */ 360 void 361 procfs_hashdone() 362 { 363 hashdone(pfs_hashtbl, M_UFSMNT); 364 } 365 366 struct vnode * 367 procfs_hashget(pid, type, mp) 368 pid_t pid; 369 pfstype type; 370 struct mount *mp; 371 { 372 struct pfsnode *pp; 373 struct vnode *vp; 374 375 loop: 376 simple_lock(&pfs_hash_slock); 377 for (pp = PFSPIDHASH(pid)->lh_first; pp; pp = pp->pfs_hash.le_next) { 378 vp = PFSTOV(pp); 379 if (pid == pp->pfs_pid && pp->pfs_type == type && 380 vp->v_mount == mp) { 381 simple_lock(&vp->v_interlock); 382 simple_unlock(&pfs_hash_slock); 383 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) 384 goto loop; 385 return (vp); 386 } 387 } 388 simple_unlock(&pfs_hash_slock); 389 return (NULL); 390 } 391 392 /* 393 * Insert the pfsnode into the hash table and lock it. 394 */ 395 void 396 procfs_hashins(pp) 397 struct pfsnode *pp; 398 { 399 struct pfs_hashhead *ppp; 400 401 /* lock the pfsnode, then put it on the appropriate hash list */ 402 lockmgr(&pp->pfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0); 403 404 simple_lock(&pfs_hash_slock); 405 ppp = PFSPIDHASH(pp->pfs_pid); 406 LIST_INSERT_HEAD(ppp, pp, pfs_hash); 407 simple_unlock(&pfs_hash_slock); 408 } 409 410 /* 411 * Remove the pfsnode from the hash table. 412 */ 413 void 414 procfs_hashrem(pp) 415 struct pfsnode *pp; 416 { 417 simple_lock(&pfs_hash_slock); 418 LIST_REMOVE(pp, pfs_hash); 419 simple_unlock(&pfs_hash_slock); 420 } 421 422 void 423 procfs_revoke_vnodes(p, arg) 424 struct proc *p; 425 void *arg; 426 { 427 struct pfsnode *pfs, *pnext; 428 struct vnode *vp; 429 struct mount *mp = (struct mount *)arg; 430 431 if (!(p->p_flag & P_SUGID)) 432 return; 433 434 for (pfs = PFSPIDHASH(p->p_pid)->lh_first; pfs; pfs = pnext) { 435 vp = PFSTOV(pfs); 436 pnext = pfs->pfs_hash.le_next; 437 if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid && 438 vp->v_mount == mp) 439 VOP_REVOKE(vp, REVOKEALL); 440 } 441 } 442
Indexes created Sun Sep 28 16:09:52 GMT 2025