1 /* $NetBSD: perfused.c,v 1.13 2011/05/30 14:50:08 manu Exp $ */ 2 3 /*- 4 * Copyright (c) 2010 Emmanuel Dreyfus. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 17 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 19 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25 * POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <stdio.h> 29 #include <unistd.h> 30 #include <stdlib.h> 31 #include <fcntl.h> 32 #include <syslog.h> 33 #include <ctype.h> 34 #include <paths.h> 35 #include <stdarg.h> 36 #include <err.h> 37 #include <errno.h> 38 #include <string.h> 39 #include <sysexits.h> 40 #include <signal.h> 41 #include <puffs.h> 42 #include <sys/wait.h> 43 #include <sys/param.h> 44 #include <sys/queue.h> 45 #include <sys/uio.h> 46 #include <sys/socket.h> 47 #include <sys/un.h> 48 #include <machine/vmparam.h> 49 50 #include "../../lib/libperfuse/perfuse_if.h" 51 #include "perfused.h" 52 53 static int access_mount(const char *, uid_t, int); 54 static void new_mount(int, int); 55 static int parse_debug(char *); 56 static void siginfo_handler(int); 57 static int parse_options(int, char **); 58 static void get_mount_info(int, struct perfuse_mount_info *, int); 59 int main(int, char **); 60 61 /* 62 * Flags for new_mount() 63 */ 64 #define PMNT_DEVFUSE 0x0 /* We use /dev/fuse */ 65 #define PMNT_SOCKPAIR 0x1 /* We use socketpair */ 66 #define PMNT_DGRAM 0x2 /* We use SOCK_DGRAM sockets */ 67 68 69 static int 70 access_mount(mnt, uid, ro) 71 const char *mnt; 72 uid_t uid; 73 int ro; 74 { 75 struct stat st; 76 mode_t mode; 77 78 if (uid == 0) 79 return 0; 80 81 if (stat(mnt, &st) == -1) 82 return -1; 83 84 if (st.st_uid != uid) 85 return -1; 86 87 mode = S_IRUSR; 88 if (!ro) 89 mode |= S_IWUSR; 90 91 if ((st.st_mode & mode) == mode) 92 return 0; 93 94 return -1; 95 } 96 97 static void 98 get_mount_info(fd, pmi, sock_type) 99 int fd; 100 struct perfuse_mount_info *pmi; 101 int sock_type; 102 { 103 struct perfuse_mount_out *pmo; 104 struct sockcred cred; 105 int opt; 106 char *cp; 107 char *source = NULL; 108 char *target = NULL; 109 char *filesystemtype = NULL; 110 long mountflags = 0; 111 void *data = NULL; 112 char *sock = NULL; 113 114 pmo = (struct perfuse_mount_out *) 115 perfuse_recv_early(fd, &cred, sizeof(cred)); 116 117 if (pmo == NULL) { 118 if (shutdown(fd, SHUT_RDWR) != 0) 119 DERR(EX_OSERR, "shutdown failed"); 120 exit(EX_PROTOCOL); 121 } 122 123 /* 124 * We do not need peer creds beyond this point 125 */ 126 opt = 0; 127 if (setsockopt(fd, 0, LOCAL_CREDS, &opt, sizeof(opt)) != 0) 128 DWARN("%s: setsockopt LOCAL_CREDS failed", __func__); 129 130 #ifdef PERFUSE_DEBUG 131 if (perfuse_diagflags & PDF_MISC) 132 DPRINTF("perfuse lengths: source = %"PRId32", " 133 "target = %"PRId32", filesystemtype = %"PRId32", " 134 "data = %"PRId32", sock = %"PRId32"\n", 135 pmo->pmo_source_len, pmo->pmo_target_len, 136 pmo->pmo_filesystemtype_len, pmo->pmo_data_len, 137 pmo->pmo_sock_len); 138 #endif 139 cp = (char *)(void *)(pmo + 1); 140 141 if (pmo->pmo_source_len != 0) { 142 source = cp; 143 cp += pmo->pmo_source_len; 144 } 145 146 if (pmo->pmo_target_len != 0) { 147 target = cp; 148 cp += pmo->pmo_target_len; 149 } 150 151 if (pmo->pmo_filesystemtype_len != 0) { 152 filesystemtype = cp; 153 cp += pmo->pmo_filesystemtype_len; 154 } 155 156 mountflags = pmo->pmo_mountflags; 157 158 if (pmo->pmo_data_len != 0) { 159 data = cp; 160 cp += pmo->pmo_data_len; 161 } 162 163 if (pmo->pmo_sock_len != 0) { 164 sock = cp; 165 cp += pmo->pmo_sock_len; 166 } 167 168 #ifdef PERFUSE_DEBUG 169 if (perfuse_diagflags & PDF_MISC) 170 DPRINTF("%s(\"%s\", \"%s\", \"%s\", 0x%lx, \"%s\", \"%s\")\n", 171 __func__, source, target, filesystemtype, 172 mountflags, (const char *)data, sock); 173 #endif 174 pmi->pmi_source = source; 175 pmi->pmi_target = target; 176 pmi->pmi_filesystemtype = filesystemtype; 177 pmi->pmi_mountflags = (int)mountflags; 178 pmi->pmi_data = data; 179 180 pmi->pmi_uid = cred.sc_euid; 181 182 /* 183 * Connect to the remote socket if provided ans using SOCK_DGRAM 184 */ 185 if ((sock_type == SOCK_DGRAM) && sock) { 186 const struct sockaddr *sa; 187 struct sockaddr_un sun; 188 189 sa = (const struct sockaddr *)(void *)&sun; 190 sun.sun_len = sizeof(sun); 191 sun.sun_family = AF_LOCAL; 192 strcpy(sun.sun_path, sock); 193 194 if (connect(fd, sa, sun.sun_len) != 0) 195 DERR(EX_OSERR, "connect \"%s\" failed", sun.sun_path); 196 } 197 198 return; 199 } 200 201 static void 202 new_mount(fd, pmnt_flags) 203 int fd; 204 int pmnt_flags; 205 { 206 struct puffs_usermount *pu; 207 struct perfuse_mount_info pmi; 208 struct perfuse_callbacks pc; 209 int ro_flag; 210 pid_t pid; 211 int flags; 212 int sock_type; 213 214 pid = (perfuse_diagflags & PDF_FOREGROUND) ? 0 : fork(); 215 switch(pid) { 216 case -1: 217 DERR(EX_OSERR, "cannot fork"); 218 break; 219 case 0: 220 break; 221 default: 222 return; 223 /* NOTREACHED */ 224 break; 225 } 226 227 /* 228 * Mount information (source, target, mount flags...) 229 */ 230 sock_type = pmnt_flags & PMNT_DGRAM ? SOCK_DGRAM : SOCK_SEQPACKET; 231 get_mount_info(fd, &pmi, sock_type); 232 233 /* 234 * Check that peer owns mountpoint and read (and write) on it? 235 */ 236 ro_flag = pmi.pmi_mountflags & MNT_RDONLY; 237 if (access_mount(pmi.pmi_target, pmi.pmi_uid, ro_flag) != 0) 238 DERRX(EX_NOPERM, "insuficient privileges to mount on %s", 239 pmi.pmi_target); 240 241 242 /* 243 * Initialize libperfuse, which will initialize libpuffs 244 */ 245 pc.pc_new_msg = perfuse_new_pb; 246 pc.pc_xchg_msg = perfuse_xchg_pb; 247 pc.pc_destroy_msg = (perfuse_destroy_msg_fn)puffs_framebuf_destroy; 248 pc.pc_get_inhdr = perfuse_get_inhdr; 249 pc.pc_get_inpayload = perfuse_get_inpayload; 250 pc.pc_get_outhdr = perfuse_get_outhdr; 251 pc.pc_get_outpayload = perfuse_get_outpayload; 252 pc.pc_umount = perfuse_umount; 253 254 pu = perfuse_init(&pc, &pmi); 255 256 puffs_framev_init(pu, perfuse_readframe, perfuse_writeframe, 257 perfuse_cmpframe, perfuse_gotframe, perfuse_fdnotify); 258 259 if (puffs_framev_addfd(pu, fd, PUFFS_FBIO_READ|PUFFS_FBIO_WRITE) == -1) 260 DERR(EX_SOFTWARE, "puffs_framev_addfd failed"); 261 262 perfuse_setspecific(pu, (void *)(long)fd); 263 264 setproctitle("perfused %s", pmi.pmi_target); 265 (void)kill(getpid(), SIGINFO); /* This is for -s option */ 266 267 perfuse_fs_init(pu); 268 269 /* 270 * Non blocking I/O on /dev/fuse 271 * This must be done after perfuse_fs_init 272 */ 273 if ((flags = fcntl(fd, F_GETFL, 0)) == -1) 274 DERR(EX_OSERR, "fcntl failed"); 275 if (fcntl(fd, F_SETFL, flags|O_NONBLOCK) != 0) 276 DERR(EX_OSERR, "fcntl failed"); 277 278 /* 279 * Hand over control to puffs main loop. 280 */ 281 if (perfuse_mainloop(pu) != 0) 282 DERRX(EX_SOFTWARE, "perfuse_mainloop exit"); 283 284 /* 285 * Normal return after unmount 286 */ 287 return; 288 } 289 290 static int 291 parse_debug(optstr) 292 char *optstr; 293 { 294 int retval = PDF_SYSLOG; 295 char *opt; 296 char *lastp; 297 298 for (opt = strtok_r(optstr, ",", &lastp); 299 opt; 300 opt = strtok_r(NULL, ",", &lastp)) { 301 if (strcmp(opt, "fuse") == 0) 302 retval |= PDF_FUSE; 303 else if (strcmp(opt, "puffs") == 0) 304 retval |= PDF_PUFFS; 305 else if (strcmp(opt, "dump") == 0) 306 retval |= PDF_DUMP; 307 else if (strcmp(opt, "fh") == 0) 308 retval |= PDF_FH; 309 else if (strcmp(opt, "readdir") == 0) 310 retval |= PDF_READDIR; 311 else if (strcmp(opt, "reclaim") == 0) 312 retval |= PDF_RECLAIM; 313 else if (strcmp(opt, "requeue") == 0) 314 retval |= PDF_REQUEUE; 315 else if (strcmp(opt, "sync") == 0) 316 retval |= PDF_SYNC; 317 else if (strcmp(opt, "misc") == 0) 318 retval |= PDF_MISC; 319 else if (strcmp(opt, "filename") == 0) 320 retval |= PDF_FILENAME; 321 else 322 DWARNX("unknown debug flag \"%s\"", opt); 323 } 324 325 return retval; 326 } 327 328 /* ARGSUSED0 */ 329 static void 330 siginfo_handler(sig) 331 int sig; 332 { 333 static int old_flags = 0; 334 int swap; 335 336 swap = perfuse_diagflags; 337 perfuse_diagflags = old_flags; 338 old_flags = swap; 339 340 DWARNX("debug %sabled", old_flags == 0 ? "en" : "dis"); 341 342 return; 343 } 344 345 static int 346 parse_options(argc, argv) 347 int argc; 348 char **argv; 349 { 350 int ch; 351 int foreground = 0; 352 int retval = -1; 353 354 perfuse_diagflags = PDF_FOREGROUND | PDF_SYSLOG; 355 356 while ((ch = getopt(argc, argv, "d:fsi:")) != -1) { 357 switch (ch) { 358 case 'd': 359 perfuse_diagflags |= parse_debug(optarg); 360 break; 361 case 's': 362 if (signal(SIGINFO, siginfo_handler) != 0) 363 DERR(EX_OSERR, "signal failed"); 364 break; 365 case 'f': 366 foreground = 1; 367 perfuse_diagflags |= PDF_MISC; 368 break; 369 case 'i': 370 retval = atoi(optarg); 371 foreground = 1; 372 break; 373 default: 374 DERRX(EX_USAGE, "%s [-fs] [-d classes] [-i fd]", argv[0]); 375 break; 376 } 377 } 378 379 if (!foreground) 380 perfuse_diagflags &= ~PDF_FOREGROUND; 381 382 return retval; 383 } 384 385 int 386 main(argc, argv) 387 int argc; 388 char **argv; 389 { 390 int s; 391 int sock_type; 392 socklen_t len; 393 394 s = parse_options(argc, argv); 395 396 if (perfuse_diagflags & PDF_SYSLOG) 397 openlog("perfused", 0, LOG_DAEMON); 398 399 if (!(perfuse_diagflags & PDF_FOREGROUND)) 400 if (daemon(0, 0) != 0) 401 DERR(EX_OSERR, "daemon failed"); 402 403 if (s != -1) { 404 new_mount(s, PMNT_SOCKPAIR); 405 exit(0); 406 } 407 408 s = perfuse_open_sock(); 409 410 #ifdef PERFUSE_DEBUG 411 if (perfuse_diagflags & PDF_MISC) 412 DPRINTF("perfused ready\n"); 413 #endif 414 len = sizeof(sock_type); 415 if (getsockopt(s, SOL_SOCKET, SO_TYPE, &sock_type, &len) != 0) 416 DERR(EX_OSERR, "getsockopt SO_TYPE failed"); 417 418 switch(sock_type) { 419 case SOCK_DGRAM: 420 new_mount(s, PMNT_DEVFUSE|PMNT_DGRAM); 421 exit(0); 422 break; 423 case SOCK_SEQPACKET: 424 if (listen(s, 0) != 0) 425 DERR(EX_OSERR, "listen failed"); 426 427 do { 428 int fd; 429 struct sockaddr_un sun; 430 struct sockaddr *sa; 431 432 len = sizeof(sun); 433 sa = (struct sockaddr *)(void *)&sun; 434 if ((fd = accept(s, sa, &len)) == -1) 435 DERR(EX_OSERR, "accept failed"); 436 437 new_mount(fd, PMNT_DEVFUSE); 438 } while (1 /* CONSTCOND */); 439 break; 440 default: 441 DERRX(EX_SOFTWARE, "unexpected so_type %d", sock_type); 442 break; 443 } 444 445 /* NOTREACHED */ 446 return 0; 447 } 448