1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1994 5 * The Regents of the University of California. 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 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/param.h> 33 #include <sys/mount.h> 34 #include <sys/stat.h> 35 #include <sys/uio.h> 36 37 #include <err.h> 38 #include <errno.h> 39 #include <paths.h> 40 #include <stdarg.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 45 #include "mntopts.h" 46 47 int getmnt_silent = 0; 48 49 void 50 getmntopts(const char *options, const struct mntopt *m0, int *flagp, 51 int *altflagp) 52 { 53 const struct mntopt *m; 54 int negative, len; 55 char *opt, *optbuf, *p; 56 int *thisflagp; 57 58 /* Copy option string, since it is about to be torn asunder... */ 59 if ((optbuf = strdup(options)) == NULL) 60 err(1, NULL); 61 62 for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) { 63 /* Check for "no" prefix. */ 64 if (opt[0] == 'n' && opt[1] == 'o') { 65 negative = 1; 66 opt += 2; 67 } else 68 negative = 0; 69 70 /* 71 * for options with assignments in them (ie. quotas) 72 * ignore the assignment as it's handled elsewhere 73 */ 74 p = strchr(opt, '='); 75 if (p != NULL) 76 *++p = '\0'; 77 78 /* Scan option table. */ 79 for (m = m0; m->m_option != NULL; ++m) { 80 len = strlen(m->m_option); 81 if (strncasecmp(opt, m->m_option, len) == 0) 82 if (opt[len] == '\0' || opt[len] == '=') 83 break; 84 } 85 86 /* Save flag, or fail if option is not recognized. */ 87 if (m->m_option) { 88 thisflagp = m->m_altloc ? altflagp : flagp; 89 if (negative == m->m_inverse) 90 *thisflagp |= m->m_flag; 91 else 92 *thisflagp &= ~m->m_flag; 93 } else if (!getmnt_silent) { 94 errx(1, "-o %s: option not supported", opt); 95 } 96 } 97 98 free(optbuf); 99 } 100 101 void 102 rmslashes(char *rrpin, char *rrpout) 103 { 104 char *rrpoutstart; 105 106 *rrpout = *rrpin; 107 for (rrpoutstart = rrpout; *rrpin != '\0'; *rrpout++ = *rrpin++) { 108 109 /* skip all double slashes */ 110 while (*rrpin == '/' && *(rrpin + 1) == '/') 111 rrpin++; 112 } 113 114 /* remove trailing slash if necessary */ 115 if (rrpout - rrpoutstart > 1 && *(rrpout - 1) == '/') 116 *(rrpout - 1) = '\0'; 117 else 118 *rrpout = '\0'; 119 } 120 121 int 122 checkpath(const char *path, char *resolved) 123 { 124 struct stat sb; 125 126 if (realpath(path, resolved) == NULL || stat(resolved, &sb) != 0) 127 return (1); 128 if (!S_ISDIR(sb.st_mode)) { 129 errno = ENOTDIR; 130 return (1); 131 } 132 return (0); 133 } 134 135 int 136 checkpath_allow_file(const char *path, char *resolved) 137 { 138 struct stat sb; 139 140 if (realpath(path, resolved) == NULL || stat(resolved, &sb) != 0) 141 return (1); 142 if (!S_ISDIR(sb.st_mode) && !S_ISREG(sb.st_mode)) { 143 errno = ENOTDIR; 144 return (1); 145 } 146 return (0); 147 } 148 149 /* 150 * Get the mount point information for name. Name may be mount point name 151 * or device name (with or without /dev/ preprended). 152 */ 153 struct statfs * 154 getmntpoint(const char *name) 155 { 156 struct stat devstat, mntdevstat; 157 char device[sizeof(_PATH_DEV) - 1 + MNAMELEN]; 158 char *ddevname; 159 struct statfs *mntbuf, *statfsp; 160 int i, mntsize, isdev; 161 u_long len; 162 163 if (stat(name, &devstat) != 0) 164 return (NULL); 165 if (S_ISCHR(devstat.st_mode) || S_ISBLK(devstat.st_mode)) 166 isdev = 1; 167 else 168 isdev = 0; 169 mntsize = getmntinfo(&mntbuf, MNT_NOWAIT); 170 for (i = 0; i < mntsize; i++) { 171 statfsp = &mntbuf[i]; 172 if (isdev == 0) { 173 if (strcmp(name, statfsp->f_mntonname)) 174 continue; 175 return (statfsp); 176 } 177 ddevname = statfsp->f_mntfromname; 178 if (*ddevname != '/') { 179 if ((len = strlen(_PATH_DEV) + strlen(ddevname) + 1) > 180 sizeof(statfsp->f_mntfromname) || 181 len > sizeof(device)) 182 continue; 183 strncpy(device, _PATH_DEV, len); 184 strncat(device, ddevname, len); 185 if (stat(device, &mntdevstat) == 0) 186 strncpy(statfsp->f_mntfromname, device, len); 187 } 188 if (stat(ddevname, &mntdevstat) == 0 && 189 mntdevstat.st_rdev == devstat.st_rdev) 190 return (statfsp); 191 } 192 return (NULL); 193 } 194 195 /* 196 * If possible reload a mounted filesystem. 197 * When prtmsg != NULL print a warning if a reload is attempted, but fails. 198 * Return 0 on success, 1 on failure. 199 */ 200 int 201 chkdoreload(struct statfs *mntp, 202 void (*prtmsg)(const char *, ...) __printflike(1,2)) 203 { 204 struct iovec *iov; 205 int iovlen, error; 206 char errmsg[255]; 207 208 /* 209 * If the filesystem is not mounted it does not need to be reloaded. 210 * If it is mounted for writing, then it could not have been opened 211 * for writing by a utility, so does not need to be reloaded. 212 */ 213 if (mntp == NULL || (mntp->f_flags & MNT_RDONLY) == 0) 214 return (0); 215 216 /* 217 * We modified a mounted file system. Do a mount update on 218 * it so we can continue using it as safely as possible. 219 */ 220 iov = NULL; 221 iovlen = 0; 222 errmsg[0] = '\0'; 223 build_iovec(&iov, &iovlen, "fstype", __DECONST(void *, "ffs"), 4); 224 build_iovec(&iov, &iovlen, "from", mntp->f_mntfromname, (size_t)-1); 225 build_iovec(&iov, &iovlen, "fspath", mntp->f_mntonname, (size_t)-1); 226 build_iovec(&iov, &iovlen, "errmsg", errmsg, sizeof(errmsg)); 227 build_iovec(&iov, &iovlen, "update", NULL, 0); 228 build_iovec(&iov, &iovlen, "reload", NULL, 0); 229 /* 230 * XX: We need the following line until we clean up 231 * nmount parsing of root mounts and NFS root mounts. 232 */ 233 build_iovec(&iov, &iovlen, "ro", NULL, 0); 234 error = nmount(iov, iovlen, mntp->f_flags); 235 free_iovec(&iov, &iovlen); 236 if (error == 0) 237 return (0); 238 if (prtmsg != NULL) 239 prtmsg("mount reload of '%s' failed: %s %s\n\n", 240 mntp->f_mntonname, strerror(errno), errmsg); 241 return (1); 242 } 243 244 void 245 build_iovec(struct iovec **iov, int *iovlen, const char *name, void *val, 246 size_t len) 247 { 248 int i; 249 250 if (*iovlen < 0) 251 return; 252 i = *iovlen; 253 *iov = realloc(*iov, sizeof **iov * (i + 2)); 254 if (*iov == NULL) { 255 *iovlen = -1; 256 return; 257 } 258 (*iov)[i].iov_base = strdup(name); 259 (*iov)[i].iov_len = strlen(name) + 1; 260 i++; 261 (*iov)[i].iov_base = val; 262 if (len == (size_t)-1) { 263 if (val != NULL) 264 len = strlen(val) + 1; 265 else 266 len = 0; 267 } 268 (*iov)[i].iov_len = (int)len; 269 *iovlen = ++i; 270 } 271 272 /* 273 * This function is needed for compatibility with parameters 274 * which used to use the mount_argf() command for the old mount() syscall. 275 */ 276 void 277 build_iovec_argf(struct iovec **iov, int *iovlen, const char *name, 278 const char *fmt, ...) 279 { 280 va_list ap; 281 char val[255] = { 0 }; 282 283 va_start(ap, fmt); 284 vsnprintf(val, sizeof(val), fmt, ap); 285 va_end(ap); 286 build_iovec(iov, iovlen, name, strdup(val), (size_t)-1); 287 } 288 289 /* 290 * Free the iovec and reset to NULL with zero length. Useful for calling 291 * nmount in a loop. 292 */ 293 void 294 free_iovec(struct iovec **iov, int *iovlen) 295 { 296 int i; 297 298 for (i = 0; i < *iovlen; i += 2) 299 free((*iov)[i].iov_base); 300 free(*iov); 301 } 302