1 /* $NetBSD: getfsspecname.c,v 1.7 2018/10/06 23:48:00 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2012 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 #include <sys/cdefs.h> 32 __RCSID("$NetBSD: getfsspecname.c,v 1.7 2018/10/06 23:48:00 christos Exp $"); 33 34 #include <sys/types.h> 35 #include <sys/ioctl.h> 36 #include <sys/sysctl.h> 37 #include <sys/disk.h> 38 39 #include <stdio.h> 40 #include <vis.h> 41 #include <string.h> 42 #include <fstab.h> 43 #include <fcntl.h> 44 #include <stdlib.h> 45 #include <errno.h> 46 #include <unistd.h> 47 #include <util.h> 48 49 #define COMPAT_DKWEDGE /* To be removed */ 50 51 const char * 52 getfsspecname(char *buf, size_t bufsiz, const char *name) 53 { 54 static const int mib[] = { CTL_HW, HW_DISKNAMES }; 55 static const unsigned int miblen = __arraycount(mib); 56 char *drives, *dk, *p; 57 size_t len; 58 int fd, savee = errno; 59 char *vname; 60 61 p = drives = vname = NULL; 62 63 /* 64 * If the name starts with "ROOT.", replace it with "/dev/<root_device>", 65 * where <root_device> is the value of the kern.root_device sysctl. Any 66 * characters after the special "ROOT." token are appended to the end 67 * of this path. 68 */ 69 if (strncasecmp(name, "ROOT.", 5) == 0 && strchr(name, ':') == NULL) { 70 static const int mib_root[] = { CTL_KERN, KERN_ROOT_DEVICE }; 71 static const unsigned int mib_rootlen = __arraycount(mib_root); 72 73 strlcpy(buf, "/dev/", bufsiz); 74 len = bufsiz - 5; 75 if (sysctl(mib_root, mib_rootlen, buf + 5, &len, NULL, 0) == -1) { 76 savee = errno; 77 strlcpy(buf, "sysctl kern.root_device failed", bufsiz); 78 goto out; 79 } 80 strlcat(buf, name + 5, bufsiz); 81 return buf; 82 } 83 84 if (strncasecmp(name, "NAME=", 5) != 0) { 85 #ifdef COMPAT_DKWEDGE 86 /* 87 * We try to open the disk name, and if we fail with EBUSY 88 * we use the name as the label to find the wedge. 89 */ 90 char rbuf[MAXPATHLEN]; 91 if (name[0] == '/') { 92 if (getdiskrawname(rbuf, sizeof(rbuf), name) != NULL) { 93 if ((fd = open(rbuf, O_RDONLY)) == -1) { 94 if (errno == EBUSY) { 95 name = strrchr(name, '/') + 1; 96 goto search; 97 } 98 } else 99 close(fd); 100 } 101 } 102 #endif 103 strlcpy(buf, name, bufsiz); 104 return buf; 105 } else 106 name += 5; 107 108 #ifdef COMPAT_DKWEDGE 109 search: 110 #endif 111 vname = malloc(strlen(name) * 4 + 1); 112 if (vname == NULL) { 113 savee = errno; 114 strlcpy(buf, "malloc failed", bufsiz); 115 goto out; 116 } 117 118 strunvis(vname, name); 119 120 if (sysctl(mib, miblen, NULL, &len, NULL, 0) == -1) { 121 savee = errno; 122 strlcpy(buf, "sysctl hw.disknames failed", bufsiz); 123 goto out; 124 } 125 126 drives = malloc(len); 127 if (drives == NULL) { 128 savee = errno; 129 strlcpy(buf, "malloc failed", bufsiz); 130 goto out; 131 } 132 if (sysctl(mib, miblen, drives, &len, NULL, 0) == -1) { 133 savee = errno; 134 strlcpy(buf, "sysctl hw.disknames failed", bufsiz); 135 goto out; 136 } 137 138 for (dk = strtok(drives, " "); dk != NULL; dk = strtok(NULL, " ")) { 139 struct dkwedge_info dkw; 140 if (strncmp(dk, "dk", 2) != 0) 141 continue; 142 fd = opendisk(dk, O_RDONLY, buf, bufsiz, 0); 143 if (fd == -1) 144 continue; 145 if (ioctl(fd, DIOCGWEDGEINFO, &dkw) == -1) { 146 savee = errno; 147 snprintf(buf, bufsiz, "%s: getwedgeinfo", dk); 148 (void)close(fd); 149 goto out; 150 } 151 (void)close(fd); 152 if (strcmp(vname, (char *)dkw.dkw_wname) == 0) { 153 p = strstr(buf, "/rdk"); 154 goto good; 155 } 156 } 157 #ifdef COMPAT_DKWEDGE 158 /* Last ditch effort assuming NAME=label, and label is a disk name */ 159 fd = opendisk(name, O_RDONLY, buf, bufsiz, 0); 160 if (fd != -1) { 161 close(fd); 162 p = strstr(buf, "/r"); 163 goto good; 164 } 165 #endif 166 savee = ESRCH; 167 snprintf(buf, bufsiz, "no match for `%s'", vname); 168 out: 169 buf = NULL; 170 good: 171 if (p++ != NULL) 172 strcpy(p, p + 1); 173 free(drives); 174 free(vname); 175 errno = savee; 176 return buf; 177 } 178