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_data *data = fuse_get_mpdata(mp); 126 struct fuse_dispatcher fdi; 127 const struct fuse_open_out default_foo = { 128 .fh = 0, 129 .open_flags = FOPEN_KEEP_CACHE, 130 .padding = 0 131 }; 132 struct fuse_open_in *foi = NULL; 133 const struct fuse_open_out *foo; 134 fufh_type_t fufh_type; 135 int dataflags = data->dataflags; 136 int err = 0; 137 int oflags = 0; 138 int op = FUSE_OPEN; 139 int relop = FUSE_RELEASE; 140 int fsess_no_op_support = FSESS_NO_OPEN_SUPPORT; 141 142 fufh_type = fflags_2_fufh_type(a_mode); 143 oflags = fufh_type_2_fflags(fufh_type); 144 145 if (vnode_isdir(vp)) { 146 op = FUSE_OPENDIR; 147 relop = FUSE_RELEASEDIR; 148 fsess_no_op_support = FSESS_NO_OPENDIR_SUPPORT; 149 /* vn_open_vnode already rejects FWRITE on directories */ 150 MPASS(fufh_type == FUFH_RDONLY || fufh_type == FUFH_EXEC); 151 } 152 fdisp_init(&fdi, sizeof(*foi)); 153 if (fsess_not_impl(mp, op) && dataflags & fsess_no_op_support) { 154 /* The operation implicitly succeeds */ 155 foo = &default_foo; 156 } else { 157 fdisp_make_vp(&fdi, op, vp, td, cred); 158 159 foi = fdi.indata; 160 foi->flags = oflags; 161 162 err = fdisp_wait_answ(&fdi); 163 if (err == ENOSYS && dataflags & fsess_no_op_support) { 164 /* The operation implicitly succeeds */ 165 foo = &default_foo; 166 fsess_set_notimpl(mp, op); 167 fsess_set_notimpl(mp, relop); 168 err = 0; 169 } else if (err) { 170 SDT_PROBE2(fusefs, , file, trace, 1, 171 "OUCH ... daemon didn't give fh"); 172 if (err == ENOENT) 173 fuse_internal_vnode_disappear(vp); 174 goto out; 175 } else { 176 foo = fdi.answ; 177 } 178 } 179 180 fuse_filehandle_init(vp, fufh_type, fufhp, td, cred, foo); 181 fuse_vnode_open(vp, foo->open_flags, td); 182 183 out: 184 if (foi) 185 fdisp_destroy(&fdi); 186 return err; 187 } 188 189 int 190 fuse_filehandle_close(struct vnode *vp, struct fuse_filehandle *fufh, 191 struct thread *td, struct ucred *cred) 192 { 193 struct mount *mp = vnode_mount(vp); 194 struct fuse_dispatcher fdi; 195 struct fuse_release_in *fri; 196 197 int err = 0; 198 int op = FUSE_RELEASE; 199 200 if (fuse_isdeadfs(vp)) { 201 goto out; 202 } 203 if (vnode_isdir(vp)) 204 op = FUSE_RELEASEDIR; 205 206 if (fsess_not_impl(mp, op)) 207 goto out; 208 209 fdisp_init(&fdi, sizeof(*fri)); 210 fdisp_make_vp(&fdi, op, vp, td, cred); 211 fri = fdi.indata; 212 fri->fh = fufh->fh_id; 213 fri->flags = fufh_type_2_fflags(fufh->fufh_type); 214 /* 215 * If the file has a POSIX lock then we're supposed to set lock_owner. 216 * If not, then lock_owner is undefined. So we may as well always set 217 * it. 218 */ 219 fri->lock_owner = td->td_proc->p_pid; 220 221 err = fdisp_wait_answ(&fdi); 222 fdisp_destroy(&fdi); 223 224 out: 225 counter_u64_add(fuse_fh_count, -1); 226 LIST_REMOVE(fufh, next); 227 free(fufh, M_FUSE_FILEHANDLE); 228 229 return err; 230 } 231 232 /* 233 * Check for a valid file handle, first the type requested, but if that 234 * isn't valid, try for FUFH_RDWR. 235 * Return true if there is any file handle with the correct credentials and 236 * a fufh type that includes the provided one. 237 * A pid of 0 means "don't care" 238 */ 239 bool 240 fuse_filehandle_validrw(struct vnode *vp, int mode, 241 struct ucred *cred, pid_t pid) 242 { 243 struct fuse_vnode_data *fvdat = VTOFUD(vp); 244 struct fuse_filehandle *fufh; 245 fufh_type_t fufh_type = fflags_2_fufh_type(mode); 246 247 /* 248 * Unlike fuse_filehandle_get, we want to search for a filehandle with 249 * the exact cred, and no fallback 250 */ 251 LIST_FOREACH(fufh, &fvdat->handles, next) { 252 if (fufh->fufh_type == fufh_type && 253 fufh->uid == cred->cr_uid && 254 fufh->gid == cred->cr_rgid && 255 (pid == 0 || fufh->pid == pid)) 256 return true; 257 } 258 259 if (fufh_type == FUFH_EXEC) 260 return false; 261 262 /* Fallback: find a RDWR list entry with the right cred */ 263 LIST_FOREACH(fufh, &fvdat->handles, next) { 264 if (fufh->fufh_type == FUFH_RDWR && 265 fufh->uid == cred->cr_uid && 266 fufh->gid == cred->cr_rgid && 267 (pid == 0 || fufh->pid == pid)) 268 return true; 269 } 270 271 return false; 272 } 273 274 int 275 fuse_filehandle_get(struct vnode *vp, int fflag, 276 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 277 { 278 struct fuse_vnode_data *fvdat = VTOFUD(vp); 279 struct fuse_filehandle *fufh; 280 fufh_type_t fufh_type; 281 282 fufh_type = fflags_2_fufh_type(fflag); 283 /* cred can be NULL for in-kernel clients */ 284 if (cred == NULL) 285 goto fallback; 286 287 LIST_FOREACH(fufh, &fvdat->handles, next) { 288 if (fufh->fufh_type == fufh_type && 289 fufh->uid == cred->cr_uid && 290 fufh->gid == cred->cr_rgid && 291 (pid == 0 || fufh->pid == pid)) 292 goto found; 293 } 294 295 fallback: 296 /* Fallback: find a list entry with the right flags */ 297 LIST_FOREACH(fufh, &fvdat->handles, next) { 298 if (fufh->fufh_type == fufh_type) 299 break; 300 } 301 302 if (fufh == NULL) 303 return EBADF; 304 305 found: 306 if (fufhp != NULL) 307 *fufhp = fufh; 308 return 0; 309 } 310 311 /* Get a file handle with any kind of flags */ 312 int 313 fuse_filehandle_get_anyflags(struct vnode *vp, 314 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 315 { 316 struct fuse_vnode_data *fvdat = VTOFUD(vp); 317 struct fuse_filehandle *fufh; 318 319 if (cred == NULL) 320 goto fallback; 321 322 LIST_FOREACH(fufh, &fvdat->handles, next) { 323 if (fufh->uid == cred->cr_uid && 324 fufh->gid == cred->cr_rgid && 325 (pid == 0 || fufh->pid == pid)) 326 goto found; 327 } 328 329 fallback: 330 /* Fallback: find any list entry */ 331 fufh = LIST_FIRST(&fvdat->handles); 332 333 if (fufh == NULL) 334 return EBADF; 335 336 found: 337 if (fufhp != NULL) 338 *fufhp = fufh; 339 return 0; 340 } 341 342 int 343 fuse_filehandle_getrw(struct vnode *vp, int fflag, 344 struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid) 345 { 346 int err; 347 348 err = fuse_filehandle_get(vp, fflag, fufhp, cred, pid); 349 if (err) 350 err = fuse_filehandle_get(vp, FREAD | FWRITE, fufhp, cred, pid); 351 return err; 352 } 353 354 void 355 fuse_filehandle_init(struct vnode *vp, fufh_type_t fufh_type, 356 struct fuse_filehandle **fufhp, struct thread *td, const struct ucred *cred, 357 const struct fuse_open_out *foo) 358 { 359 struct fuse_vnode_data *fvdat = VTOFUD(vp); 360 struct fuse_filehandle *fufh; 361 362 fufh = malloc(sizeof(struct fuse_filehandle), M_FUSE_FILEHANDLE, 363 M_WAITOK); 364 MPASS(fufh != NULL); 365 fufh->fh_id = foo->fh; 366 fufh->fufh_type = fufh_type; 367 fufh->gid = cred->cr_rgid; 368 fufh->uid = cred->cr_uid; 369 fufh->pid = td->td_proc->p_pid; 370 fufh->fuse_open_flags = foo->open_flags; 371 if (!FUFH_IS_VALID(fufh)) { 372 panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type); 373 } 374 LIST_INSERT_HEAD(&fvdat->handles, fufh, next); 375 if (fufhp != NULL) 376 *fufhp = fufh; 377 378 counter_u64_add(fuse_fh_count, 1); 379 380 if (foo->open_flags & FOPEN_DIRECT_IO) { 381 ASSERT_VOP_ELOCKED(vp, __func__); 382 VTOFUD(vp)->flag |= FN_DIRECTIO; 383 fuse_io_invalbuf(vp, td); 384 } else { 385 if ((foo->open_flags & FOPEN_KEEP_CACHE) == 0) 386 fuse_io_invalbuf(vp, td); 387 VTOFUD(vp)->flag &= ~FN_DIRECTIO; 388 } 389 390 } 391 392 void 393 fuse_file_init(void) 394 { 395 fuse_fh_count = counter_u64_alloc(M_WAITOK); 396 } 397 398 void 399 fuse_file_destroy(void) 400 { 401 counter_u64_free(fuse_fh_count); 402 } 403