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/param.h> 64 #include <sys/systm.h> 65 #include <sys/counter.h> 66 #include <sys/module.h> 67 #include <sys/errno.h> 68 #include <sys/kernel.h> 69 #include <sys/conf.h> 70 #include <sys/uio.h> 71 #include <sys/malloc.h> 72 #include <sys/queue.h> 73 #include <sys/lock.h> 74 #include <sys/sx.h> 75 #include <sys/mutex.h> 76 #include <sys/proc.h> 77 #include <sys/mount.h> 78 #include <sys/vnode.h> 79 #include <sys/sdt.h> 80 #include <sys/sysctl.h> 81 82 #include "fuse.h" 83 #include "fuse_file.h" 84 #include "fuse_internal.h" 85 #include "fuse_io.h" 86 #include "fuse_ipc.h" 87 #include "fuse_node.h" 88 89 MALLOC_DEFINE(M_FUSE_FILEHANDLE, "fuse_filefilehandle", "FUSE file handle"); 90 91 SDT_PROVIDER_DECLARE(fusefs); 92 /* 93 * Fuse trace probe: 94 * arg0: verbosity. Higher numbers give more verbose messages 95 * arg1: Textual message 96 */ 97 SDT_PROBE_DEFINE2(fusefs, , file, trace, "int", "char*"); 98 99 static counter_u64_t fuse_fh_count; 100 101 SYSCTL_COUNTER_U64(_vfs_fusefs_stats, OID_AUTO, filehandle_count, CTLFLAG_RD, 102 &fuse_fh_count, "number of open FUSE filehandles"); 103 104 /* Get the FUFH type for a particular access mode */ 105 static inline fufh_type_t 106 fflags_2_fufh_type(int fflags) 107 { 108 if ((fflags & FREAD) && (fflags & FWRITE)) 109 return FUFH_RDWR; 110 else if (fflags & (FWRITE)) 111 return FUFH_WRONLY; 112 else if (fflags & (FREAD)) 113 return FUFH_RDONLY; 114 else if (fflags & (FEXEC)) 115 return FUFH_EXEC; 116 else 117 panic("FUSE: What kind of a flag is this (%x)?", fflags); 118 } 119 120 int 121 fuse_filehandle_open(struct vnode *vp, int a_mode, 122 struct fuse_filehandle **fufhp, struct thread *td, struct ucred *cred) 123 { 124 struct mount *mp = vnode_mount(vp); 125 struct fuse_dispatcher fdi; 126 const struct fuse_open_out default_foo = { 127 .fh = 0, 128 .open_flags = FOPEN_KEEP_CACHE, 129 .padding = 0 130 }; 131 struct fuse_open_in *foi = NULL; 132 const struct fuse_open_out *foo; 133 fufh_type_t fufh_type; 134 int err = 0; 135 int oflags = 0; 136 int op = FUSE_OPEN; 137 int relop = FUSE_RELEASE; 138 139 fufh_type = fflags_2_fufh_type(a_mode); 140 oflags = fufh_type_2_fflags(fufh_type); 141 142 if (vnode_isdir(vp)) { 143 op = FUSE_OPENDIR; 144 relop = FUSE_RELEASEDIR; 145 /* vn_open_vnode already rejects FWRITE on directories */ 146 MPASS(fufh_type == FUFH_RDONLY || fufh_type == FUFH_EXEC); 147 } 148 fdisp_init(&fdi, sizeof(*foi)); 149 if (fsess_not_impl(mp, op)) { 150 /* The operation implicitly succeeds */ 151 foo = &default_foo; 152 } else { 153 fdisp_make_vp(&fdi, op, vp, td, cred); 154 155 foi = fdi.indata; 156 foi->flags = oflags; 157 158 err = fdisp_wait_answ(&fdi); 159 if (err == ENOSYS) { 160 /* The operation implicitly succeeds */ 161 foo = &default_foo; 162 fsess_set_notimpl(mp, op); 163 fsess_set_notimpl(mp, relop); 164 err = 0; 165 } else if (err) { 166 SDT_PROBE2(fusefs, , file, trace, 1, 167 "OUCH ... daemon didn't give fh"); 168 if (err == ENOENT) 169 fuse_internal_vnode_disappear(vp); 170 goto out; 171 } else { 172 foo = fdi.answ; 173 fsess_set_impl(mp, op); 174 } 175 } 176 177 fuse_filehandle_init(vp, fufh_type, fufhp, td, cred, foo); 178 fuse_vnode_open(vp, foo->open_flags, td); 179 180 out: 181 if (foi) 182 fdisp_destroy(&fdi); 183 return err; 184 } 185 186 int 187 fuse_filehandle_close(struct vnode *vp, struct fuse_filehandle *fufh, 188 struct thread *td, struct ucred *cred) 189 { 190 struct mount *mp = vnode_mount(vp); 191 struct fuse_dispatcher fdi; 192 struct fuse_release_in *fri; 193 194 int err = 0; 195 int op = FUSE_RELEASE; 196 197 ASSERT_VOP_ELOCKED(vp, __func__); 198 199 if (fuse_isdeadfs(vp)) { 200 goto out; 201 } 202 if (vnode_isdir(vp)) 203 op = FUSE_RELEASEDIR; 204 205 if (fsess_not_impl(mp, op)) 206 goto out; 207 208 fdisp_init(&fdi, sizeof(*fri)); 209 fdisp_make_vp(&fdi, op, vp, td, cred); 210 fri = fdi.indata; 211 fri->fh = fufh->fh_id; 212 fri->flags = fufh_type_2_fflags(fufh->fufh_type); 213 /* 214 * If the file has a POSIX lock then we're supposed to set lock_owner. 215 * If not, then lock_owner is undefined. So we may as well always set 216 * it. 217 */ 218 fri->lock_owner = td->td_proc->p_pid; 219 220 err = fdisp_wait_answ(&fdi); 221 fdisp_destroy(&fdi); 222 223 out: 224 counter_u64_add(fuse_fh_count, -1); 225 LIST_REMOVE(fufh, next); 226 free(fufh, M_FUSE_FILEHANDLE); 227 228 return err; 229 } 230 231 /* 232 * Check for a valid file handle, first the type requested, but if that 233 * isn't valid, try for FUFH_RDWR. 234 * Return true if there is any file handle with the correct credentials and 235 * a fufh type that includes the provided one. 236 * A pid of 0 means "don't care" 237 */ 238 bool 239 fuse_filehandle_validrw(struct vnode *vp, int mode, 240 struct ucred *cred, pid_t pid) 241 { 242 struct fuse_vnode_data *fvdat = VTOFUD(vp); 243 struct fuse_filehandle *fufh; 244 fufh_type_t fufh_type = fflags_2_fufh_type(mode); 245 246 /* 247 * Unlike fuse_filehandle_get, we want to search for a filehandle with 248 * the exact cred, and no fallback 249 */ 250 LIST_FOREACH(fufh, &fvdat->handles, next) { 251 if (fufh->fufh_type == fufh_type && 252 fufh->uid == cred->cr_uid && 253 fufh->gid == cred->cr_rgid && 254 (pid == 0 || fufh->pid == pid)) 255 return true; 256 } 257 258 if (fufh_type == FUFH_EXEC) 259 return false; 260 261 /* Fallback: find a RDWR list entry with the right cred */ 262 LIST_FOREACH(fufh, &fvdat->handles, next) { 263 if (fufh->fufh_type == FUFH_RDWR && 264 fufh->uid == cred->cr_uid && 265 fufh->gid == cred->cr_rgid && 266 (pid == 0 || fufh->pid == pid)) 267 return true; 268 } 269 270 return false; 271 } 272 273 int 274 fuse_filehandle_get(struct vnode *vp, int fflag, 275 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 276 { 277 struct fuse_vnode_data *fvdat = VTOFUD(vp); 278 struct fuse_filehandle *fufh; 279 fufh_type_t fufh_type; 280 281 fufh_type = fflags_2_fufh_type(fflag); 282 /* cred can be NULL for in-kernel clients */ 283 if (cred == NULL) 284 goto fallback; 285 286 LIST_FOREACH(fufh, &fvdat->handles, next) { 287 if (fufh->fufh_type == fufh_type && 288 fufh->uid == cred->cr_uid && 289 fufh->gid == cred->cr_rgid && 290 (pid == 0 || fufh->pid == pid)) 291 goto found; 292 } 293 294 fallback: 295 /* Fallback: find a list entry with the right flags */ 296 LIST_FOREACH(fufh, &fvdat->handles, next) { 297 if (fufh->fufh_type == fufh_type) 298 break; 299 } 300 301 if (fufh == NULL) 302 return EBADF; 303 304 found: 305 if (fufhp != NULL) 306 *fufhp = fufh; 307 return 0; 308 } 309 310 /* Get a file handle with any kind of flags */ 311 int 312 fuse_filehandle_get_anyflags(struct vnode *vp, 313 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 314 { 315 struct fuse_vnode_data *fvdat = VTOFUD(vp); 316 struct fuse_filehandle *fufh; 317 318 if (cred == NULL) 319 goto fallback; 320 321 LIST_FOREACH(fufh, &fvdat->handles, next) { 322 if (fufh->uid == cred->cr_uid && 323 fufh->gid == cred->cr_rgid && 324 (pid == 0 || fufh->pid == pid)) 325 goto found; 326 } 327 328 fallback: 329 /* Fallback: find any list entry */ 330 fufh = LIST_FIRST(&fvdat->handles); 331 332 if (fufh == NULL) 333 return EBADF; 334 335 found: 336 if (fufhp != NULL) 337 *fufhp = fufh; 338 return 0; 339 } 340 341 int 342 fuse_filehandle_getrw(struct vnode *vp, int fflag, 343 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 344 { 345 int err; 346 347 err = fuse_filehandle_get(vp, fflag, fufhp, cred, pid); 348 if (err) 349 err = fuse_filehandle_get(vp, FREAD | FWRITE, fufhp, cred, pid); 350 return err; 351 } 352 353 void 354 fuse_filehandle_init(struct vnode *vp, fufh_type_t fufh_type, 355 struct fuse_filehandle **fufhp, struct thread *td, const struct ucred *cred, 356 const struct fuse_open_out *foo) 357 { 358 struct fuse_vnode_data *fvdat = VTOFUD(vp); 359 struct fuse_filehandle *fufh; 360 361 fufh = malloc(sizeof(struct fuse_filehandle), M_FUSE_FILEHANDLE, 362 M_WAITOK); 363 MPASS(fufh != NULL); 364 fufh->fh_id = foo->fh; 365 fufh->fufh_type = fufh_type; 366 fufh->gid = cred->cr_rgid; 367 fufh->uid = cred->cr_uid; 368 fufh->pid = td->td_proc->p_pid; 369 fufh->fuse_open_flags = foo->open_flags; 370 if (!FUFH_IS_VALID(fufh)) { 371 panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type); 372 } 373 LIST_INSERT_HEAD(&fvdat->handles, fufh, next); 374 if (fufhp != NULL) 375 *fufhp = fufh; 376 377 counter_u64_add(fuse_fh_count, 1); 378 379 if (foo->open_flags & FOPEN_DIRECT_IO) { 380 ASSERT_VOP_ELOCKED(vp, __func__); 381 VTOFUD(vp)->flag |= FN_DIRECTIO; 382 fuse_io_invalbuf(vp, td); 383 } else { 384 if ((foo->open_flags & FOPEN_KEEP_CACHE) == 0) 385 fuse_io_invalbuf(vp, td); 386 /* 387 * XXX Update the flag without the lock for now. See 388 * https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=293088 389 */ 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