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 if (fuse_isdeadfs(vp)) { 198 goto out; 199 } 200 if (vnode_isdir(vp)) 201 op = FUSE_RELEASEDIR; 202 203 if (fsess_not_impl(mp, op)) 204 goto out; 205 206 fdisp_init(&fdi, sizeof(*fri)); 207 fdisp_make_vp(&fdi, op, vp, td, cred); 208 fri = fdi.indata; 209 fri->fh = fufh->fh_id; 210 fri->flags = fufh_type_2_fflags(fufh->fufh_type); 211 /* 212 * If the file has a POSIX lock then we're supposed to set lock_owner. 213 * If not, then lock_owner is undefined. So we may as well always set 214 * it. 215 */ 216 fri->lock_owner = td->td_proc->p_pid; 217 218 err = fdisp_wait_answ(&fdi); 219 fdisp_destroy(&fdi); 220 221 out: 222 counter_u64_add(fuse_fh_count, -1); 223 LIST_REMOVE(fufh, next); 224 free(fufh, M_FUSE_FILEHANDLE); 225 226 return err; 227 } 228 229 /* 230 * Check for a valid file handle, first the type requested, but if that 231 * isn't valid, try for FUFH_RDWR. 232 * Return true if there is any file handle with the correct credentials and 233 * a fufh type that includes the provided one. 234 * A pid of 0 means "don't care" 235 */ 236 bool 237 fuse_filehandle_validrw(struct vnode *vp, int mode, 238 struct ucred *cred, pid_t pid) 239 { 240 struct fuse_vnode_data *fvdat = VTOFUD(vp); 241 struct fuse_filehandle *fufh; 242 fufh_type_t fufh_type = fflags_2_fufh_type(mode); 243 244 /* 245 * Unlike fuse_filehandle_get, we want to search for a filehandle with 246 * the exact cred, and no fallback 247 */ 248 LIST_FOREACH(fufh, &fvdat->handles, next) { 249 if (fufh->fufh_type == fufh_type && 250 fufh->uid == cred->cr_uid && 251 fufh->gid == cred->cr_rgid && 252 (pid == 0 || fufh->pid == pid)) 253 return true; 254 } 255 256 if (fufh_type == FUFH_EXEC) 257 return false; 258 259 /* Fallback: find a RDWR list entry with the right cred */ 260 LIST_FOREACH(fufh, &fvdat->handles, next) { 261 if (fufh->fufh_type == FUFH_RDWR && 262 fufh->uid == cred->cr_uid && 263 fufh->gid == cred->cr_rgid && 264 (pid == 0 || fufh->pid == pid)) 265 return true; 266 } 267 268 return false; 269 } 270 271 int 272 fuse_filehandle_get(struct vnode *vp, int fflag, 273 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 274 { 275 struct fuse_vnode_data *fvdat = VTOFUD(vp); 276 struct fuse_filehandle *fufh; 277 fufh_type_t fufh_type; 278 279 fufh_type = fflags_2_fufh_type(fflag); 280 /* cred can be NULL for in-kernel clients */ 281 if (cred == NULL) 282 goto fallback; 283 284 LIST_FOREACH(fufh, &fvdat->handles, next) { 285 if (fufh->fufh_type == fufh_type && 286 fufh->uid == cred->cr_uid && 287 fufh->gid == cred->cr_rgid && 288 (pid == 0 || fufh->pid == pid)) 289 goto found; 290 } 291 292 fallback: 293 /* Fallback: find a list entry with the right flags */ 294 LIST_FOREACH(fufh, &fvdat->handles, next) { 295 if (fufh->fufh_type == fufh_type) 296 break; 297 } 298 299 if (fufh == NULL) 300 return EBADF; 301 302 found: 303 if (fufhp != NULL) 304 *fufhp = fufh; 305 return 0; 306 } 307 308 /* Get a file handle with any kind of flags */ 309 int 310 fuse_filehandle_get_anyflags(struct vnode *vp, 311 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 312 { 313 struct fuse_vnode_data *fvdat = VTOFUD(vp); 314 struct fuse_filehandle *fufh; 315 316 if (cred == NULL) 317 goto fallback; 318 319 LIST_FOREACH(fufh, &fvdat->handles, next) { 320 if (fufh->uid == cred->cr_uid && 321 fufh->gid == cred->cr_rgid && 322 (pid == 0 || fufh->pid == pid)) 323 goto found; 324 } 325 326 fallback: 327 /* Fallback: find any list entry */ 328 fufh = LIST_FIRST(&fvdat->handles); 329 330 if (fufh == NULL) 331 return EBADF; 332 333 found: 334 if (fufhp != NULL) 335 *fufhp = fufh; 336 return 0; 337 } 338 339 int 340 fuse_filehandle_getrw(struct vnode *vp, int fflag, 341 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 342 { 343 int err; 344 345 err = fuse_filehandle_get(vp, fflag, fufhp, cred, pid); 346 if (err) 347 err = fuse_filehandle_get(vp, FREAD | FWRITE, fufhp, cred, pid); 348 return err; 349 } 350 351 void 352 fuse_filehandle_init(struct vnode *vp, fufh_type_t fufh_type, 353 struct fuse_filehandle **fufhp, struct thread *td, const struct ucred *cred, 354 const struct fuse_open_out *foo) 355 { 356 struct fuse_vnode_data *fvdat = VTOFUD(vp); 357 struct fuse_filehandle *fufh; 358 359 fufh = malloc(sizeof(struct fuse_filehandle), M_FUSE_FILEHANDLE, 360 M_WAITOK); 361 MPASS(fufh != NULL); 362 fufh->fh_id = foo->fh; 363 fufh->fufh_type = fufh_type; 364 fufh->gid = cred->cr_rgid; 365 fufh->uid = cred->cr_uid; 366 fufh->pid = td->td_proc->p_pid; 367 fufh->fuse_open_flags = foo->open_flags; 368 if (!FUFH_IS_VALID(fufh)) { 369 panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type); 370 } 371 LIST_INSERT_HEAD(&fvdat->handles, fufh, next); 372 if (fufhp != NULL) 373 *fufhp = fufh; 374 375 counter_u64_add(fuse_fh_count, 1); 376 377 if (foo->open_flags & FOPEN_DIRECT_IO) { 378 ASSERT_VOP_ELOCKED(vp, __func__); 379 VTOFUD(vp)->flag |= FN_DIRECTIO; 380 fuse_io_invalbuf(vp, td); 381 } else { 382 if ((foo->open_flags & FOPEN_KEEP_CACHE) == 0) 383 fuse_io_invalbuf(vp, td); 384 VTOFUD(vp)->flag &= ~FN_DIRECTIO; 385 } 386 387 } 388 389 void 390 fuse_file_init(void) 391 { 392 fuse_fh_count = counter_u64_alloc(M_WAITOK); 393 } 394 395 void 396 fuse_file_destroy(void) 397 { 398 counter_u64_free(fuse_fh_count); 399 } 400