1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2007-2009 Google Inc. and Amit Singh 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are 9 * met: 10 * 11 * * Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * * Redistributions in binary form must reproduce the above 14 * copyright notice, this list of conditions and the following disclaimer 15 * in the documentation and/or other materials provided with the 16 * distribution. 17 * * Neither the name of Google Inc. nor the names of its 18 * contributors may be used to endorse or promote products derived from 19 * this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 24 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 25 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 27 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 * 33 * Copyright (C) 2005 Csaba Henk. 34 * All rights reserved. 35 * 36 * Copyright (c) 2019 The FreeBSD Foundation 37 * 38 * Portions of this software were developed by BFF Storage Systems, LLC under 39 * sponsorship from the FreeBSD Foundation. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 50 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 */ 62 63 #include <sys/cdefs.h> 64 __FBSDID("$FreeBSD$"); 65 66 #include <sys/param.h> 67 #include <sys/systm.h> 68 #include <sys/counter.h> 69 #include <sys/module.h> 70 #include <sys/errno.h> 71 #include <sys/kernel.h> 72 #include <sys/conf.h> 73 #include <sys/uio.h> 74 #include <sys/malloc.h> 75 #include <sys/queue.h> 76 #include <sys/lock.h> 77 #include <sys/sx.h> 78 #include <sys/mutex.h> 79 #include <sys/proc.h> 80 #include <sys/mount.h> 81 #include <sys/vnode.h> 82 #include <sys/sdt.h> 83 #include <sys/sysctl.h> 84 85 #include "fuse.h" 86 #include "fuse_file.h" 87 #include "fuse_internal.h" 88 #include "fuse_io.h" 89 #include "fuse_ipc.h" 90 #include "fuse_node.h" 91 92 MALLOC_DEFINE(M_FUSE_FILEHANDLE, "fuse_filefilehandle", "FUSE file handle"); 93 94 SDT_PROVIDER_DECLARE(fusefs); 95 /* 96 * Fuse trace probe: 97 * arg0: verbosity. Higher numbers give more verbose messages 98 * arg1: Textual message 99 */ 100 SDT_PROBE_DEFINE2(fusefs, , file, trace, "int", "char*"); 101 102 static counter_u64_t fuse_fh_count; 103 104 SYSCTL_COUNTER_U64(_vfs_fusefs_stats, OID_AUTO, filehandle_count, CTLFLAG_RD, 105 &fuse_fh_count, "number of open FUSE filehandles"); 106 107 /* Get the FUFH type for a particular access mode */ 108 static inline fufh_type_t 109 fflags_2_fufh_type(int fflags) 110 { 111 if ((fflags & FREAD) && (fflags & FWRITE)) 112 return FUFH_RDWR; 113 else if (fflags & (FWRITE)) 114 return FUFH_WRONLY; 115 else if (fflags & (FREAD)) 116 return FUFH_RDONLY; 117 else if (fflags & (FEXEC)) 118 return FUFH_EXEC; 119 else 120 panic("FUSE: What kind of a flag is this (%x)?", fflags); 121 } 122 123 int 124 fuse_filehandle_open(struct vnode *vp, int a_mode, 125 struct fuse_filehandle **fufhp, struct thread *td, struct ucred *cred) 126 { 127 struct mount *mp = vnode_mount(vp); 128 struct fuse_data *data = fuse_get_mpdata(mp); 129 struct fuse_dispatcher fdi; 130 const struct fuse_open_out default_foo = { 131 .fh = 0, 132 .open_flags = FOPEN_KEEP_CACHE, 133 .padding = 0 134 }; 135 struct fuse_open_in *foi = NULL; 136 const struct fuse_open_out *foo; 137 fufh_type_t fufh_type; 138 int dataflags = data->dataflags; 139 int err = 0; 140 int oflags = 0; 141 int op = FUSE_OPEN; 142 int relop = FUSE_RELEASE; 143 int fsess_no_op_support = FSESS_NO_OPEN_SUPPORT; 144 145 fufh_type = fflags_2_fufh_type(a_mode); 146 oflags = fufh_type_2_fflags(fufh_type); 147 148 if (vnode_isdir(vp)) { 149 op = FUSE_OPENDIR; 150 relop = FUSE_RELEASEDIR; 151 fsess_no_op_support = FSESS_NO_OPENDIR_SUPPORT; 152 /* vn_open_vnode already rejects FWRITE on directories */ 153 MPASS(fufh_type == FUFH_RDONLY || fufh_type == FUFH_EXEC); 154 } 155 fdisp_init(&fdi, sizeof(*foi)); 156 if (fsess_not_impl(mp, op) && dataflags & fsess_no_op_support) { 157 /* The operation implicitly succeeds */ 158 foo = &default_foo; 159 } else { 160 fdisp_make_vp(&fdi, op, vp, td, cred); 161 162 foi = fdi.indata; 163 foi->flags = oflags; 164 165 err = fdisp_wait_answ(&fdi); 166 if (err == ENOSYS && dataflags & fsess_no_op_support) { 167 /* The operation implicitly succeeds */ 168 foo = &default_foo; 169 fsess_set_notimpl(mp, op); 170 fsess_set_notimpl(mp, relop); 171 err = 0; 172 } else if (err) { 173 SDT_PROBE2(fusefs, , file, trace, 1, 174 "OUCH ... daemon didn't give fh"); 175 if (err == ENOENT) 176 fuse_internal_vnode_disappear(vp); 177 goto out; 178 } else { 179 foo = fdi.answ; 180 } 181 } 182 183 fuse_filehandle_init(vp, fufh_type, fufhp, td, cred, foo); 184 fuse_vnode_open(vp, foo->open_flags, td); 185 186 out: 187 if (foi) 188 fdisp_destroy(&fdi); 189 return err; 190 } 191 192 int 193 fuse_filehandle_close(struct vnode *vp, struct fuse_filehandle *fufh, 194 struct thread *td, struct ucred *cred) 195 { 196 struct mount *mp = vnode_mount(vp); 197 struct fuse_dispatcher fdi; 198 struct fuse_release_in *fri; 199 200 int err = 0; 201 int op = FUSE_RELEASE; 202 203 if (fuse_isdeadfs(vp)) { 204 goto out; 205 } 206 if (vnode_isdir(vp)) 207 op = FUSE_RELEASEDIR; 208 209 if (fsess_not_impl(mp, op)) 210 goto out; 211 212 fdisp_init(&fdi, sizeof(*fri)); 213 fdisp_make_vp(&fdi, op, vp, td, cred); 214 fri = fdi.indata; 215 fri->fh = fufh->fh_id; 216 fri->flags = fufh_type_2_fflags(fufh->fufh_type); 217 /* 218 * If the file has a POSIX lock then we're supposed to set lock_owner. 219 * If not, then lock_owner is undefined. So we may as well always set 220 * it. 221 */ 222 fri->lock_owner = td->td_proc->p_pid; 223 224 err = fdisp_wait_answ(&fdi); 225 fdisp_destroy(&fdi); 226 227 out: 228 counter_u64_add(fuse_fh_count, -1); 229 LIST_REMOVE(fufh, next); 230 free(fufh, M_FUSE_FILEHANDLE); 231 232 return err; 233 } 234 235 /* 236 * Check for a valid file handle, first the type requested, but if that 237 * isn't valid, try for FUFH_RDWR. 238 * Return true if there is any file handle with the correct credentials and 239 * a fufh type that includes the provided one. 240 * A pid of 0 means "don't care" 241 */ 242 bool 243 fuse_filehandle_validrw(struct vnode *vp, int mode, 244 struct ucred *cred, pid_t pid) 245 { 246 struct fuse_vnode_data *fvdat = VTOFUD(vp); 247 struct fuse_filehandle *fufh; 248 fufh_type_t fufh_type = fflags_2_fufh_type(mode); 249 250 /* 251 * Unlike fuse_filehandle_get, we want to search for a filehandle with 252 * the exact cred, and no fallback 253 */ 254 LIST_FOREACH(fufh, &fvdat->handles, next) { 255 if (fufh->fufh_type == fufh_type && 256 fufh->uid == cred->cr_uid && 257 fufh->gid == cred->cr_rgid && 258 (pid == 0 || fufh->pid == pid)) 259 return true; 260 } 261 262 if (fufh_type == FUFH_EXEC) 263 return false; 264 265 /* Fallback: find a RDWR list entry with the right cred */ 266 LIST_FOREACH(fufh, &fvdat->handles, next) { 267 if (fufh->fufh_type == FUFH_RDWR && 268 fufh->uid == cred->cr_uid && 269 fufh->gid == cred->cr_rgid && 270 (pid == 0 || fufh->pid == pid)) 271 return true; 272 } 273 274 return false; 275 } 276 277 int 278 fuse_filehandle_get(struct vnode *vp, int fflag, 279 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 280 { 281 struct fuse_vnode_data *fvdat = VTOFUD(vp); 282 struct fuse_filehandle *fufh; 283 fufh_type_t fufh_type; 284 285 fufh_type = fflags_2_fufh_type(fflag); 286 /* cred can be NULL for in-kernel clients */ 287 if (cred == NULL) 288 goto fallback; 289 290 LIST_FOREACH(fufh, &fvdat->handles, next) { 291 if (fufh->fufh_type == fufh_type && 292 fufh->uid == cred->cr_uid && 293 fufh->gid == cred->cr_rgid && 294 (pid == 0 || fufh->pid == pid)) 295 goto found; 296 } 297 298 fallback: 299 /* Fallback: find a list entry with the right flags */ 300 LIST_FOREACH(fufh, &fvdat->handles, next) { 301 if (fufh->fufh_type == fufh_type) 302 break; 303 } 304 305 if (fufh == NULL) 306 return EBADF; 307 308 found: 309 if (fufhp != NULL) 310 *fufhp = fufh; 311 return 0; 312 } 313 314 /* Get a file handle with any kind of flags */ 315 int 316 fuse_filehandle_get_anyflags(struct vnode *vp, 317 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 318 { 319 struct fuse_vnode_data *fvdat = VTOFUD(vp); 320 struct fuse_filehandle *fufh; 321 322 if (cred == NULL) 323 goto fallback; 324 325 LIST_FOREACH(fufh, &fvdat->handles, next) { 326 if (fufh->uid == cred->cr_uid && 327 fufh->gid == cred->cr_rgid && 328 (pid == 0 || fufh->pid == pid)) 329 goto found; 330 } 331 332 fallback: 333 /* Fallback: find any list entry */ 334 fufh = LIST_FIRST(&fvdat->handles); 335 336 if (fufh == NULL) 337 return EBADF; 338 339 found: 340 if (fufhp != NULL) 341 *fufhp = fufh; 342 return 0; 343 } 344 345 int 346 fuse_filehandle_getrw(struct vnode *vp, int fflag, 347 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 348 { 349 int err; 350 351 err = fuse_filehandle_get(vp, fflag, fufhp, cred, pid); 352 if (err) 353 err = fuse_filehandle_get(vp, FREAD | FWRITE, fufhp, cred, pid); 354 return err; 355 } 356 357 void 358 fuse_filehandle_init(struct vnode *vp, fufh_type_t fufh_type, 359 struct fuse_filehandle **fufhp, struct thread *td, const struct ucred *cred, 360 const struct fuse_open_out *foo) 361 { 362 struct fuse_vnode_data *fvdat = VTOFUD(vp); 363 struct fuse_filehandle *fufh; 364 365 fufh = malloc(sizeof(struct fuse_filehandle), M_FUSE_FILEHANDLE, 366 M_WAITOK); 367 MPASS(fufh != NULL); 368 fufh->fh_id = foo->fh; 369 fufh->fufh_type = fufh_type; 370 fufh->gid = cred->cr_rgid; 371 fufh->uid = cred->cr_uid; 372 fufh->pid = td->td_proc->p_pid; 373 fufh->fuse_open_flags = foo->open_flags; 374 if (!FUFH_IS_VALID(fufh)) { 375 panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type); 376 } 377 LIST_INSERT_HEAD(&fvdat->handles, fufh, next); 378 if (fufhp != NULL) 379 *fufhp = fufh; 380 381 counter_u64_add(fuse_fh_count, 1); 382 383 if (foo->open_flags & FOPEN_DIRECT_IO) { 384 ASSERT_VOP_ELOCKED(vp, __func__); 385 VTOFUD(vp)->flag |= FN_DIRECTIO; 386 fuse_io_invalbuf(vp, td); 387 } else { 388 if ((foo->open_flags & FOPEN_KEEP_CACHE) == 0) 389 fuse_io_invalbuf(vp, td); 390 VTOFUD(vp)->flag &= ~FN_DIRECTIO; 391 } 392 393 } 394 395 void 396 fuse_file_init(void) 397 { 398 fuse_fh_count = counter_u64_alloc(M_WAITOK); 399 } 400 401 void 402 fuse_file_destroy(void) 403 { 404 counter_u64_free(fuse_fh_count); 405 } 406