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