1 /* $NetBSD: perfused.c,v 1.11 2010/10/11 05:37:58 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 *); 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 67 68 static int 69 access_mount(mnt, uid, ro) 70 const char *mnt; 71 uid_t uid; 72 int ro; 73 { 74 struct stat st; 75 mode_t mode; 76 77 if (uid == 0) 78 return 0; 79 80 if (stat(mnt, &st) == -1) 81 return -1; 82 83 if (st.st_uid != uid) 84 return -1; 85 86 mode = S_IRUSR; 87 if (!ro) 88 mode |= S_IWUSR; 89 90 if ((st.st_mode & mode) == mode) 91 return 0; 92 93 return -1; 94 } 95 96 static void 97 get_mount_info(fd, pmi) 98 int fd; 99 struct perfuse_mount_info *pmi; 100 { 101 struct perfuse_mount_out *pmo; 102 struct sockcred cred; 103 int opt; 104 char *cp; 105 char *source = NULL; 106 char *target = NULL; 107 char *filesystemtype = NULL; 108 long mountflags = 0; 109 void *data = NULL; 110 char *sock = NULL; 111 112 pmo = (struct perfuse_mount_out *) 113 perfuse_recv_early(fd, &cred, sizeof(cred)); 114 115 if (pmo == NULL) { 116 if (shutdown(fd, SHUT_RDWR) != 0) 117 DERR(EX_OSERR, "shutdown failed"); 118 exit(EX_PROTOCOL); 119 } 120 121 /* 122 * We do not need peer creds beyond this point 123 */ 124 opt = 0; 125 if (setsockopt(fd, 0, LOCAL_CREDS, &opt, sizeof(opt)) != 0) 126 DWARN("%s: setsockopt LOCAL_CREDS failed", __func__); 127 128 #ifdef PERFUSE_DEBUG 129 if (perfuse_diagflags & PDF_MISC) 130 DPRINTF("perfuse lengths: source = %"PRId32", " 131 "target = %"PRId32", filesystemtype = %"PRId32", " 132 "data = %"PRId32", sock = %"PRId32"\n", 133 pmo->pmo_source_len, pmo->pmo_target_len, 134 pmo->pmo_filesystemtype_len, pmo->pmo_data_len, 135 pmo->pmo_sock_len); 136 #endif 137 cp = (char *)(void *)(pmo + 1); 138 139 if (pmo->pmo_source_len != 0) { 140 source = cp; 141 cp += pmo->pmo_source_len; 142 } 143 144 if (pmo->pmo_target_len != 0) { 145 target = cp; 146 cp += pmo->pmo_target_len; 147 } 148 149 if (pmo->pmo_filesystemtype_len != 0) { 150 filesystemtype = cp; 151 cp += pmo->pmo_filesystemtype_len; 152 } 153 154 mountflags = pmo->pmo_mountflags; 155 156 if (pmo->pmo_data_len != 0) { 157 data = cp; 158 cp += pmo->pmo_data_len; 159 } 160 161 if (pmo->pmo_sock_len != 0) { 162 sock = cp; 163 cp += pmo->pmo_sock_len; 164 } 165 166 #ifdef PERFUSE_DEBUG 167 if (perfuse_diagflags & PDF_MISC) 168 DPRINTF("%s(\"%s\", \"%s\", \"%s\", 0x%lx, \"%s\", \"%s\")\n", 169 __func__, source, target, filesystemtype, 170 mountflags, (const char *)data, sock); 171 #endif 172 pmi->pmi_source = source; 173 pmi->pmi_target = target; 174 pmi->pmi_filesystemtype = filesystemtype; 175 pmi->pmi_mountflags = (int)mountflags; 176 pmi->pmi_data = data; 177 178 pmi->pmi_uid = cred.sc_euid; 179 180 /* 181 * Connect to the remote socket, if provided 182 */ 183 if (sock) { 184 const struct sockaddr *sa; 185 struct sockaddr_un sun; 186 187 sa = (const struct sockaddr *)(void *)&sun; 188 sun.sun_len = sizeof(sun); 189 sun.sun_family = AF_LOCAL; 190 strcpy(sun.sun_path, sock); 191 192 if (connect(fd, sa, sun.sun_len) != 0) 193 DERR(EX_OSERR, "connect \"%s\" failed", sun.sun_path); 194 } 195 196 return; 197 } 198 199 static void 200 new_mount(fd, pmnt_flags) 201 int fd; 202 int pmnt_flags; 203 { 204 struct puffs_usermount *pu; 205 struct perfuse_mount_info pmi; 206 struct perfuse_callbacks pc; 207 int ro_flag; 208 pid_t pid; 209 int flags; 210 211 pid = (perfuse_diagflags & PDF_FOREGROUND) ? 0 : fork(); 212 switch(pid) { 213 case -1: 214 DERR(EX_OSERR, "cannot fork"); 215 break; 216 case 0: 217 break; 218 default: 219 return; 220 /* NOTREACHED */ 221 break; 222 } 223 224 /* 225 * Mount information (source, target, mount flags...) 226 */ 227 get_mount_info(fd, &pmi); 228 229 /* 230 * Check that peer owns mountpoint and read (and write) on it? 231 */ 232 ro_flag = pmi.pmi_mountflags & MNT_RDONLY; 233 if (access_mount(pmi.pmi_target, pmi.pmi_uid, ro_flag) != 0) 234 DERRX(EX_NOPERM, "insuficient privileges to mount on %s", 235 pmi.pmi_target); 236 237 238 /* 239 * Initialize libperfuse, which will initialize libpuffs 240 */ 241 pc.pc_new_msg = perfuse_new_pb; 242 pc.pc_xchg_msg = perfuse_xchg_pb; 243 pc.pc_destroy_msg = (perfuse_destroy_msg_fn)puffs_framebuf_destroy; 244 pc.pc_get_inhdr = perfuse_get_inhdr; 245 pc.pc_get_inpayload = perfuse_get_inpayload; 246 pc.pc_get_outhdr = perfuse_get_outhdr; 247 pc.pc_get_outpayload = perfuse_get_outpayload; 248 249 pu = perfuse_init(&pc, &pmi); 250 251 puffs_framev_init(pu, perfuse_readframe, perfuse_writeframe, 252 perfuse_cmpframe, perfuse_gotframe, perfuse_fdnotify); 253 254 if (puffs_framev_addfd(pu, fd, PUFFS_FBIO_READ|PUFFS_FBIO_WRITE) == -1) 255 DERR(EX_SOFTWARE, "puffs_framev_addfd failed"); 256 257 perfuse_setspecific(pu, (void *)(long)fd); 258 259 setproctitle("perfused %s", pmi.pmi_target); 260 (void)kill(getpid(), SIGINFO); /* This is for -s option */ 261 262 perfuse_fs_init(pu); 263 264 /* 265 * Non blocking I/O on /dev/fuse 266 * This must be done after perfuse_fs_init 267 */ 268 if ((flags = fcntl(fd, F_GETFL, 0)) == -1) 269 DERR(EX_OSERR, "fcntl failed"); 270 if (fcntl(fd, F_SETFL, flags|O_NONBLOCK) != 0) 271 DERR(EX_OSERR, "fcntl failed"); 272 273 /* 274 * Hand over control to puffs main loop. 275 */ 276 (void)perfuse_mainloop(pu); 277 278 DERRX(EX_SOFTWARE, "perfuse_mainloop exit"); 279 280 /* NOTREACHED */ 281 return; 282 } 283 284 static int 285 parse_debug(optstr) 286 char *optstr; 287 { 288 int retval = PDF_SYSLOG; 289 char *opt; 290 char *lastp; 291 292 for (opt = strtok_r(optstr, ",", &lastp); 293 opt; 294 opt = strtok_r(NULL, ",", &lastp)) { 295 if (strcmp(opt, "fuse") == 0) 296 retval |= PDF_FUSE; 297 else if (strcmp(opt, "puffs") == 0) 298 retval |= PDF_PUFFS; 299 else if (strcmp(opt, "dump") == 0) 300 retval |= PDF_DUMP; 301 else if (strcmp(opt, "fh") == 0) 302 retval |= PDF_FH; 303 else if (strcmp(opt, "readdir") == 0) 304 retval |= PDF_READDIR; 305 else if (strcmp(opt, "reclaim") == 0) 306 retval |= PDF_RECLAIM; 307 else if (strcmp(opt, "requeue") == 0) 308 retval |= PDF_REQUEUE; 309 else if (strcmp(opt, "sync") == 0) 310 retval |= PDF_SYNC; 311 else if (strcmp(opt, "misc") == 0) 312 retval |= PDF_MISC; 313 else if (strcmp(opt, "filename") == 0) 314 retval |= PDF_FILENAME; 315 else 316 DERRX(EX_USAGE, "unknown debug flag \"%s\"", opt); 317 } 318 319 return retval; 320 } 321 322 /* ARGSUSED0 */ 323 static void 324 siginfo_handler(sig) 325 int sig; 326 { 327 static int old_flags = 0; 328 int swap; 329 330 swap = perfuse_diagflags; 331 perfuse_diagflags = old_flags; 332 old_flags = swap; 333 334 DWARNX("debug %sabled", old_flags == 0 ? "en" : "dis"); 335 336 return; 337 } 338 339 static int 340 parse_options(argc, argv) 341 int argc; 342 char **argv; 343 { 344 int ch; 345 int foreground = 0; 346 int retval = -1; 347 348 perfuse_diagflags = PDF_FOREGROUND | PDF_SYSLOG; 349 350 while ((ch = getopt(argc, argv, "d:fsi:")) != -1) { 351 switch (ch) { 352 case 'd': 353 perfuse_diagflags |= parse_debug(optarg); 354 break; 355 case 's': 356 if (signal(SIGINFO, siginfo_handler) != 0) 357 DERR(EX_OSERR, "signal failed"); 358 break; 359 case 'f': 360 foreground = 1; 361 perfuse_diagflags |= PDF_MISC; 362 break; 363 case 'i': 364 retval = atoi(optarg); 365 foreground = 1; 366 break; 367 default: 368 DERR(EX_USAGE, "%s [-fs] [-d level] [-i fd]", argv[0]); 369 break; 370 } 371 } 372 373 if (!foreground) 374 perfuse_diagflags &= ~PDF_FOREGROUND; 375 376 return retval; 377 } 378 379 int 380 main(argc, argv) 381 int argc; 382 char **argv; 383 { 384 int s; 385 386 s = parse_options(argc, argv); 387 388 if (perfuse_diagflags & PDF_SYSLOG) 389 openlog("perfused", 0, LOG_DAEMON); 390 391 if (!(perfuse_diagflags & PDF_FOREGROUND)) 392 if (daemon(0, 0) != 0) 393 DERR(EX_OSERR, "daemon failed"); 394 395 if (s != -1) { 396 new_mount(s, PMNT_SOCKPAIR); 397 DERRX(EX_SOFTWARE, "new_mount exit while -i is used"); 398 } 399 400 s = perfuse_open_sock(); 401 402 do { 403 #ifdef PERFUSE_DEBUG 404 if (perfuse_diagflags & PDF_MISC) 405 DPRINTF("perfused ready\n"); 406 #endif 407 new_mount(s, PMNT_DEVFUSE); 408 } while (1 /* CONSTCOND */); 409 410 /* NOTREACHED */ 411 return 0; 412 } 413