1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1992, 1993, 1994 5 * The Regents of the University of California. 6 * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc. 7 * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org> 8 * All rights reserved. 9 * 10 * This code is derived from software donated to Berkeley by 11 * Jan-Simon Pendry. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 */ 37 38 #ifndef lint 39 static const char copyright[] = 40 "@(#) Copyright (c) 1992, 1993, 1994\n\ 41 The Regents of the University of California. All rights reserved.\n"; 42 #endif /* not lint */ 43 44 #ifndef lint 45 #if 0 46 static char sccsid[] = "@(#)mount_union.c 8.5 (Berkeley) 3/27/94"; 47 #else 48 static const char rcsid[] = 49 "$FreeBSD$"; 50 #endif 51 #endif /* not lint */ 52 53 #include <sys/param.h> 54 #include <sys/mount.h> 55 #include <sys/uio.h> 56 #include <sys/errno.h> 57 58 #include <err.h> 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <string.h> 62 #include <sysexits.h> 63 #include <unistd.h> 64 #include <grp.h> 65 #include <pwd.h> 66 67 #include "mntopts.h" 68 69 static int 70 subdir(const char *p, const char *dir) 71 { 72 int l; 73 74 l = strlen(dir); 75 if (l <= 1) 76 return (1); 77 78 if ((strncmp(p, dir, l) == 0) && (p[l] == '/' || p[l] == '\0')) 79 return (1); 80 81 return (0); 82 } 83 84 static void 85 usage(void) 86 { 87 (void)fprintf(stderr, 88 "usage: mount_unionfs [-o options] directory uniondir\n"); 89 exit(EX_USAGE); 90 } 91 92 static void 93 parse_gid(const char *s, char *buf, size_t bufsize) 94 { 95 struct group *gr; 96 char *inval; 97 98 if ((gr = getgrnam(s)) != NULL) 99 snprintf(buf, bufsize, "%d", gr->gr_gid); 100 else { 101 strtol(s, &inval, 10); 102 if (*inval != 0) { 103 errx(EX_NOUSER, "unknown group id: %s", s); 104 usage(); 105 } else { 106 strncpy(buf, s, bufsize); 107 } 108 } 109 } 110 111 static void 112 parse_uid(const char *s, char *buf, size_t bufsize) 113 { 114 struct passwd *pw; 115 char *inval; 116 117 if ((pw = getpwnam(s)) != NULL) 118 snprintf(buf, bufsize, "%d", pw->pw_uid); 119 else { 120 strtol(s, &inval, 10); 121 if (*inval != 0) { 122 errx(EX_NOUSER, "unknown user id: %s", s); 123 usage(); 124 } else { 125 strncpy(buf, s, bufsize); 126 } 127 } 128 } 129 130 int 131 main(int argc, char *argv[]) 132 { 133 struct iovec *iov; 134 int ch, iovlen; 135 char source [MAXPATHLEN], target[MAXPATHLEN], errmsg[255]; 136 char uid_str[20], gid_str[20]; 137 char fstype[] = "unionfs"; 138 char *p, *val; 139 140 iov = NULL; 141 iovlen = 0; 142 memset(errmsg, 0, sizeof(errmsg)); 143 144 while ((ch = getopt(argc, argv, "bo:")) != -1) { 145 switch (ch) { 146 case 'b': 147 printf("\n -b is deprecated. Use \"-o below\" instead\n"); 148 build_iovec(&iov, &iovlen, "below", NULL, 0); 149 break; 150 case 'o': 151 p = strchr(optarg, '='); 152 val = NULL; 153 if (p != NULL) { 154 *p = '\0'; 155 val = p + 1; 156 if (strcmp(optarg, "gid") == 0) { 157 parse_gid(val, gid_str, sizeof(gid_str)); 158 val = gid_str; 159 } 160 else if (strcmp(optarg, "uid") == 0) { 161 parse_uid(val, uid_str, sizeof(uid_str)); 162 val = uid_str; 163 } 164 } 165 build_iovec(&iov, &iovlen, optarg, val, (size_t)-1); 166 break; 167 case '?': 168 default: 169 usage(); 170 /* NOTREACHED */ 171 } 172 } 173 argc -= optind; 174 argv += optind; 175 176 if (argc != 2) 177 usage(); 178 179 /* resolve both target and source with realpath(3) */ 180 if (checkpath(argv[0], target) != 0) 181 err(EX_USAGE, "%s", target); 182 if (checkpath(argv[1], source) != 0) 183 err(EX_USAGE, "%s", source); 184 185 if (subdir(target, source) || subdir(source, target)) 186 errx(EX_USAGE, "%s (%s) and %s (%s) are not distinct paths", 187 argv[0], target, argv[1], source); 188 189 build_iovec(&iov, &iovlen, "fstype", fstype, (size_t)-1); 190 build_iovec(&iov, &iovlen, "fspath", source, (size_t)-1); 191 build_iovec(&iov, &iovlen, "from", target, (size_t)-1); 192 build_iovec(&iov, &iovlen, "errmsg", errmsg, sizeof(errmsg)); 193 194 if (nmount(iov, iovlen, 0)) 195 err(EX_OSERR, "%s: %s", source, errmsg); 196 exit(0); 197 } 198