xref: /freebsd/lib/libufs/type.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2002 Juli Mallett.  All rights reserved.
5  *
6  * This software was written by Juli Mallett <jmallett@FreeBSD.org> for the
7  * FreeBSD project.  Redistribution and use in source and binary forms, with
8  * or without modification, are permitted provided that the following
9  * conditions are met:
10  *
11  * 1. Redistribution of source code must retain the above copyright notice,
12  *    this list of conditions and the following disclaimer.
13  * 2. Redistribution in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
21  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
26  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>
31 #include <sys/mount.h>
32 #include <sys/disklabel.h>
33 #include <sys/stat.h>
34 
35 #include <ufs/ufs/extattr.h>
36 #include <ufs/ufs/quota.h>
37 #include <ufs/ufs/ufsmount.h>
38 #include <ufs/ufs/dinode.h>
39 #include <ufs/ffs/fs.h>
40 
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <fstab.h>
44 #include <paths.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include <libufs.h>
51 
52 /* Internally, track the 'name' value, it's ours. */
53 #define	MINE_NAME	0x01
54 /* Track if its fd points to a writable device. */
55 #define	MINE_WRITE	0x02
56 
57 int
58 ufs_disk_close(struct uufsd *disk)
59 {
60 	ERROR(disk, NULL);
61 	close(disk->d_fd);
62 	disk->d_fd = -1;
63 	if (disk->d_mine & MINE_NAME) {
64 		free((char *)(uintptr_t)disk->d_name);
65 		disk->d_name = NULL;
66 	}
67 	if (disk->d_si != NULL) {
68 		free(disk->d_si->si_csp);
69 		free(disk->d_si);
70 		disk->d_si = NULL;
71 	}
72 	return (0);
73 }
74 
75 int
76 ufs_disk_fillout(struct uufsd *disk, const char *name)
77 {
78 	if (ufs_disk_fillout_blank(disk, name) == -1) {
79 		return (-1);
80 	}
81 	if (sbread(disk) == -1) {
82 		ERROR(disk, "could not read superblock to fill out disk");
83 		ufs_disk_close(disk);
84 		return (-1);
85 	}
86 	return (0);
87 }
88 
89 int
90 ufs_disk_fillout_blank(struct uufsd *disk, const char *name)
91 {
92 	struct stat st;
93 	struct fstab *fs;
94 	struct statfs sfs;
95 	const char *oname;
96 	char dev[MAXPATHLEN];
97 	int fd, ret;
98 
99 	ERROR(disk, NULL);
100 
101 	oname = name;
102 again:	if ((ret = stat(name, &st)) < 0) {
103 		if (*name != '/') {
104 			snprintf(dev, sizeof(dev), "%s%s", _PATH_DEV, name);
105 			name = dev;
106 			goto again;
107 		}
108 		/*
109 		 * The given object doesn't exist, but don't panic just yet -
110 		 * it may be still mount point listed in /etc/fstab, but without
111 		 * existing corresponding directory.
112 		 */
113 		name = oname;
114 	}
115 	if (ret >= 0 && S_ISREG(st.st_mode)) {
116 		/* Possibly a disk image, give it a try.  */
117 		;
118 	} else if (ret >= 0 && S_ISCHR(st.st_mode)) {
119 		/* This is what we need, do nothing. */
120 		;
121 	} else if ((fs = getfsfile(name)) != NULL) {
122 		/*
123 		 * The given mount point is listed in /etc/fstab.
124 		 * It is possible that someone unmounted file system by hand
125 		 * and different file system is mounted on this mount point,
126 		 * but we still prefer /etc/fstab entry, because on the other
127 		 * hand, there could be /etc/fstab entry for this mount
128 		 * point, but file system is not mounted yet (eg. noauto) and
129 		 * statfs(2) will point us at different file system.
130 		 */
131 		name = fs->fs_spec;
132 	} else if (ret >= 0 && S_ISDIR(st.st_mode)) {
133 		/*
134 		 * The mount point is not listed in /etc/fstab, so it may be
135 		 * file system mounted by hand.
136 		 */
137 		if (statfs(name, &sfs) < 0) {
138 			ERROR(disk, "could not find special device");
139 			return (-1);
140 		}
141 		strlcpy(dev, sfs.f_mntfromname, sizeof(dev));
142 		name = dev;
143 	} else {
144 		ERROR(disk, "could not find special device");
145 		return (-1);
146 	}
147 	fd = open(name, O_RDONLY);
148 	if (fd == -1) {
149 		ERROR(disk, "could not open special device");
150 		return (-1);
151 	}
152 
153 	if (((uintptr_t)disk & ~(LIBUFS_BUFALIGN - 1)) != (uintptr_t)disk) {
154 		ERROR(disk, "uufsd structure must be aligned to "
155 		    "LIBUFS_BUFALIGN byte boundry, see ufs_disk_fillout(3)");
156 		close(fd);
157 		return (-1);
158 	}
159 
160 	disk->d_bsize = 1;
161 	disk->d_ccg = 0;
162 	disk->d_fd = fd;
163 	disk->d_inomin = 0;
164 	disk->d_inomax = 0;
165 	disk->d_lcg = 0;
166 	disk->d_mine = 0;
167 	disk->d_ufs = 0;
168 	disk->d_error = NULL;
169 	disk->d_si = NULL;
170 	disk->d_sblockloc = UFS_STDSB;
171 	disk->d_lookupflags = 0;
172 
173 	if (oname != name) {
174 		name = strdup(name);
175 		if (name == NULL) {
176 			ERROR(disk, "could not allocate memory for disk name");
177 			return (-1);
178 		}
179 		disk->d_mine |= MINE_NAME;
180 	}
181 	disk->d_name = name;
182 
183 	return (0);
184 }
185 
186 int
187 ufs_disk_write(struct uufsd *disk)
188 {
189 	int fd;
190 
191 	ERROR(disk, NULL);
192 
193 	if (disk->d_mine & MINE_WRITE)
194 		return (0);
195 
196 	fd = open(disk->d_name, O_RDWR);
197 	if (fd < 0) {
198 		ERROR(disk, "failed to open disk for writing");
199 		return (-1);
200 	}
201 
202 	close(disk->d_fd);
203 	disk->d_fd = fd;
204 	disk->d_mine |= MINE_WRITE;
205 
206 	return (0);
207 }
208