1 /* $NetBSD: procfs_vfsops.c,v 1.88 2014/02/07 15:29:22 hannken Exp $ */ 2 3 /* 4 * Copyright (c) 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Jan-Simon Pendry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)procfs_vfsops.c 8.7 (Berkeley) 5/10/95 35 */ 36 37 /* 38 * Copyright (c) 1993 Jan-Simon Pendry 39 * 40 * This code is derived from software contributed to Berkeley by 41 * Jan-Simon Pendry. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by the University of 54 * California, Berkeley and its contributors. 55 * 4. Neither the name of the University nor the names of its contributors 56 * may be used to endorse or promote products derived from this software 57 * without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 69 * SUCH DAMAGE. 70 * 71 * @(#)procfs_vfsops.c 8.7 (Berkeley) 5/10/95 72 */ 73 74 /* 75 * procfs VFS interface 76 */ 77 78 #include <sys/cdefs.h> 79 __KERNEL_RCSID(0, "$NetBSD: procfs_vfsops.c,v 1.88 2014/02/07 15:29:22 hannken Exp $"); 80 81 #if defined(_KERNEL_OPT) 82 #include "opt_compat_netbsd.h" 83 #endif 84 85 #include <sys/param.h> 86 #include <sys/time.h> 87 #include <sys/kernel.h> 88 #include <sys/systm.h> 89 #include <sys/sysctl.h> 90 #include <sys/proc.h> 91 #include <sys/buf.h> 92 #include <sys/syslog.h> 93 #include <sys/mount.h> 94 #include <sys/dirent.h> 95 #include <sys/signalvar.h> 96 #include <sys/vnode.h> 97 #include <sys/malloc.h> 98 #include <sys/kauth.h> 99 #include <sys/module.h> 100 101 #include <miscfs/genfs/genfs.h> 102 103 #include <miscfs/procfs/procfs.h> 104 105 #include <uvm/uvm_extern.h> /* for PAGE_SIZE */ 106 107 MODULE(MODULE_CLASS_VFS, procfs, NULL); 108 109 VFS_PROTOS(procfs); 110 111 static struct sysctllog *procfs_sysctl_log; 112 113 static kauth_listener_t procfs_listener; 114 115 /* 116 * VFS Operations. 117 * 118 * mount system call 119 */ 120 /* ARGSUSED */ 121 int 122 procfs_mount( 123 struct mount *mp, 124 const char *path, 125 void *data, 126 size_t *data_len) 127 { 128 struct lwp *l = curlwp; 129 struct procfsmount *pmnt; 130 struct procfs_args *args = data; 131 int error; 132 133 if (UIO_MX & (UIO_MX-1)) { 134 log(LOG_ERR, "procfs: invalid directory entry size"); 135 return (EINVAL); 136 } 137 138 if (mp->mnt_flag & MNT_GETARGS) { 139 if (*data_len < sizeof *args) 140 return EINVAL; 141 142 pmnt = VFSTOPROC(mp); 143 if (pmnt == NULL) 144 return EIO; 145 args->version = PROCFS_ARGSVERSION; 146 args->flags = pmnt->pmnt_flags; 147 *data_len = sizeof *args; 148 return 0; 149 } 150 151 if (mp->mnt_flag & MNT_UPDATE) 152 return (EOPNOTSUPP); 153 154 if (*data_len >= sizeof *args && args->version != PROCFS_ARGSVERSION) 155 return EINVAL; 156 157 pmnt = kmem_zalloc(sizeof(struct procfsmount), KM_SLEEP); 158 159 mp->mnt_stat.f_namemax = PROCFS_MAXNAMLEN; 160 mp->mnt_flag |= MNT_LOCAL; 161 mp->mnt_data = pmnt; 162 vfs_getnewfsid(mp); 163 164 error = set_statvfs_info(path, UIO_USERSPACE, "procfs", UIO_SYSSPACE, 165 mp->mnt_op->vfs_name, mp, l); 166 pmnt->pmnt_exechook = exechook_establish(procfs_revoke_vnodes, mp); 167 if (*data_len >= sizeof *args) 168 pmnt->pmnt_flags = args->flags; 169 else 170 pmnt->pmnt_flags = 0; 171 172 mp->mnt_iflag |= IMNT_MPSAFE; 173 return error; 174 } 175 176 /* 177 * unmount system call 178 */ 179 int 180 procfs_unmount(struct mount *mp, int mntflags) 181 { 182 int error; 183 int flags = 0; 184 185 if (mntflags & MNT_FORCE) 186 flags |= FORCECLOSE; 187 188 if ((error = vflush(mp, 0, flags)) != 0) 189 return (error); 190 191 exechook_disestablish(VFSTOPROC(mp)->pmnt_exechook); 192 193 kmem_free(mp->mnt_data, sizeof(struct procfsmount)); 194 mp->mnt_data = NULL; 195 196 return 0; 197 } 198 199 int 200 procfs_root(struct mount *mp, struct vnode **vpp) 201 { 202 int error; 203 204 error = procfs_allocvp(mp, vpp, 0, PFSroot, -1, NULL); 205 if (error == 0) { 206 error = vn_lock(*vpp, LK_EXCLUSIVE); 207 if (error != 0) { 208 vrele(*vpp); 209 *vpp = NULL; 210 } 211 } 212 213 return error; 214 } 215 216 /* ARGSUSED */ 217 int 218 procfs_start(struct mount *mp, int flags) 219 { 220 221 return (0); 222 } 223 224 /* 225 * Get file system statistics. 226 */ 227 int 228 procfs_statvfs(struct mount *mp, struct statvfs *sbp) 229 { 230 231 genfs_statvfs(mp, sbp); 232 233 sbp->f_bsize = PAGE_SIZE; 234 sbp->f_frsize = PAGE_SIZE; 235 sbp->f_iosize = PAGE_SIZE; 236 sbp->f_blocks = 1; 237 sbp->f_files = maxproc; /* approx */ 238 sbp->f_ffree = maxproc - nprocs; /* approx */ 239 sbp->f_favail = maxproc - nprocs; /* approx */ 240 241 return (0); 242 } 243 244 /*ARGSUSED*/ 245 int 246 procfs_sync( 247 struct mount *mp, 248 int waitfor, 249 kauth_cred_t uc) 250 { 251 252 return (0); 253 } 254 255 /*ARGSUSED*/ 256 int 257 procfs_vget(struct mount *mp, ino_t ino, 258 struct vnode **vpp) 259 { 260 return (EOPNOTSUPP); 261 } 262 263 void 264 procfs_init(void) 265 { 266 procfs_hashinit(); 267 } 268 269 void 270 procfs_reinit(void) 271 { 272 procfs_hashreinit(); 273 } 274 275 void 276 procfs_done(void) 277 { 278 procfs_hashdone(); 279 } 280 281 extern const struct vnodeopv_desc procfs_vnodeop_opv_desc; 282 283 const struct vnodeopv_desc * const procfs_vnodeopv_descs[] = { 284 &procfs_vnodeop_opv_desc, 285 NULL, 286 }; 287 288 struct vfsops procfs_vfsops = { 289 MOUNT_PROCFS, 290 sizeof (struct procfs_args), 291 procfs_mount, 292 procfs_start, 293 procfs_unmount, 294 procfs_root, 295 (void *)eopnotsupp, /* vfs_quotactl */ 296 procfs_statvfs, 297 procfs_sync, 298 procfs_vget, 299 (void *)eopnotsupp, /* vfs_fhtovp */ 300 (void *)eopnotsupp, /* vfs_vptofh */ 301 procfs_init, 302 procfs_reinit, 303 procfs_done, 304 NULL, /* vfs_mountroot */ 305 (int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp, 306 vfs_stdextattrctl, 307 (void *)eopnotsupp, /* vfs_suspendctl */ 308 genfs_renamelock_enter, 309 genfs_renamelock_exit, 310 (void *)eopnotsupp, 311 procfs_vnodeopv_descs, 312 0, 313 { NULL, NULL }, 314 }; 315 316 static int 317 procfs_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 318 void *arg0, void *arg1, void *arg2, void *arg3) 319 { 320 struct proc *p; 321 struct pfsnode *pfs; 322 enum kauth_process_req req; 323 int result; 324 325 result = KAUTH_RESULT_DEFER; 326 p = arg0; 327 pfs = arg1; 328 req = (enum kauth_process_req)(unsigned long)arg2; 329 330 if (action != KAUTH_PROCESS_PROCFS) 331 return result; 332 333 /* Privileged; let secmodel handle that. */ 334 if (req == KAUTH_REQ_PROCESS_PROCFS_CTL) 335 return result; 336 337 switch (pfs->pfs_type) { 338 case PFSregs: 339 case PFSfpregs: 340 case PFSmem: 341 if (kauth_cred_getuid(cred) != kauth_cred_getuid(p->p_cred) || 342 ISSET(p->p_flag, PK_SUGID)) 343 break; 344 345 /*FALLTHROUGH*/ 346 default: 347 result = KAUTH_RESULT_ALLOW; 348 break; 349 } 350 351 return result; 352 } 353 354 355 static int 356 procfs_modcmd(modcmd_t cmd, void *arg) 357 { 358 int error; 359 360 switch (cmd) { 361 case MODULE_CMD_INIT: 362 error = vfs_attach(&procfs_vfsops); 363 if (error != 0) 364 break; 365 sysctl_createv(&procfs_sysctl_log, 0, NULL, NULL, 366 CTLFLAG_PERMANENT, 367 CTLTYPE_NODE, "vfs", NULL, 368 NULL, 0, NULL, 0, 369 CTL_VFS, CTL_EOL); 370 sysctl_createv(&procfs_sysctl_log, 0, NULL, NULL, 371 CTLFLAG_PERMANENT, 372 CTLTYPE_NODE, "procfs", 373 SYSCTL_DESCR("Process file system"), 374 NULL, 0, NULL, 0, 375 CTL_VFS, 12, CTL_EOL); 376 /* 377 * XXX the "12" above could be dynamic, thereby eliminating 378 * one more instance of the "number to vfs" mapping problem, 379 * but "12" is the order as taken from sys/mount.h 380 */ 381 382 procfs_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS, 383 procfs_listener_cb, NULL); 384 385 break; 386 case MODULE_CMD_FINI: 387 error = vfs_detach(&procfs_vfsops); 388 if (error != 0) 389 break; 390 sysctl_teardown(&procfs_sysctl_log); 391 kauth_unlisten_scope(procfs_listener); 392 break; 393 default: 394 error = ENOTTY; 395 break; 396 } 397 398 return (error); 399 } 400