1 /* $NetBSD: ext2fs_bswap.c,v 1.25 2023/08/26 05:22:50 riastradh Exp $ */
2
3 /*
4 * Copyright (c) 1997 Manuel Bouyer.
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 AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 */
27
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: ext2fs_bswap.c,v 1.25 2023/08/26 05:22:50 riastradh Exp $");
30
31 #include <sys/types.h>
32 #include <ufs/ext2fs/ext2fs.h>
33 #include <ufs/ext2fs/ext2fs_dinode.h>
34
35 #if defined(_KERNEL)
36 #include <sys/systm.h>
37 #else
38 #include <string.h>
39 #endif
40
41 /* These functions are only needed if native byte order is not little endian */
42 #if BYTE_ORDER == BIG_ENDIAN
43 void
e2fs_sb_bswap(struct ext2fs * old,struct ext2fs * new)44 e2fs_sb_bswap(struct ext2fs *old, struct ext2fs *new)
45 {
46
47 /* preserve unused fields */
48 memcpy(new, old, sizeof(struct ext2fs));
49 new->e2fs_icount = bswap32(old->e2fs_icount);
50 new->e2fs_bcount = bswap32(old->e2fs_bcount);
51 new->e2fs_rbcount = bswap32(old->e2fs_rbcount);
52 new->e2fs_fbcount = bswap32(old->e2fs_fbcount);
53 new->e2fs_ficount = bswap32(old->e2fs_ficount);
54 new->e2fs_first_dblock = bswap32(old->e2fs_first_dblock);
55 new->e2fs_log_bsize = bswap32(old->e2fs_log_bsize);
56 new->e2fs_fsize = bswap32(old->e2fs_fsize);
57 new->e2fs_bpg = bswap32(old->e2fs_bpg);
58 new->e2fs_fpg = bswap32(old->e2fs_fpg);
59 new->e2fs_ipg = bswap32(old->e2fs_ipg);
60 new->e2fs_mtime = bswap32(old->e2fs_mtime);
61 new->e2fs_wtime = bswap32(old->e2fs_wtime);
62 new->e2fs_mnt_count = bswap16(old->e2fs_mnt_count);
63 new->e2fs_max_mnt_count = bswap16(old->e2fs_max_mnt_count);
64 new->e2fs_magic = bswap16(old->e2fs_magic);
65 new->e2fs_state = bswap16(old->e2fs_state);
66 new->e2fs_beh = bswap16(old->e2fs_beh);
67 new->e2fs_minrev = bswap16(old->e2fs_minrev);
68 new->e2fs_lastfsck = bswap32(old->e2fs_lastfsck);
69 new->e2fs_fsckintv = bswap32(old->e2fs_fsckintv);
70 new->e2fs_creator = bswap32(old->e2fs_creator);
71 new->e2fs_rev = bswap32(old->e2fs_rev);
72 new->e2fs_ruid = bswap16(old->e2fs_ruid);
73 new->e2fs_rgid = bswap16(old->e2fs_rgid);
74 new->e2fs_first_ino = bswap32(old->e2fs_first_ino);
75 new->e2fs_inode_size = bswap16(old->e2fs_inode_size);
76 new->e2fs_block_group_nr = bswap16(old->e2fs_block_group_nr);
77 new->e2fs_features_compat = bswap32(old->e2fs_features_compat);
78 new->e2fs_features_incompat = bswap32(old->e2fs_features_incompat);
79 new->e2fs_features_rocompat = bswap32(old->e2fs_features_rocompat);
80 new->e2fs_algo = bswap32(old->e2fs_algo);
81 new->e2fs_reserved_ngdb = bswap16(old->e2fs_reserved_ngdb);
82 new->e4fs_want_extra_isize = bswap16(old->e4fs_want_extra_isize);
83 }
84
85 void
e2fs_i_bswap(struct ext2fs_dinode * old,struct ext2fs_dinode * new,size_t isize)86 e2fs_i_bswap(struct ext2fs_dinode *old, struct ext2fs_dinode *new, size_t isize)
87 {
88 /* preserve non-swapped and unused fields */
89 memcpy(new, old, isize);
90
91 /* swap what needs to be swapped */
92 new->e2di_mode = bswap16(old->e2di_mode);
93 new->e2di_uid = bswap16(old->e2di_uid);
94 new->e2di_gid = bswap16(old->e2di_gid);
95 new->e2di_nlink = bswap16(old->e2di_nlink);
96 new->e2di_size = bswap32(old->e2di_size);
97 new->e2di_atime = bswap32(old->e2di_atime);
98 new->e2di_ctime = bswap32(old->e2di_ctime);
99 new->e2di_mtime = bswap32(old->e2di_mtime);
100 new->e2di_dtime = bswap32(old->e2di_dtime);
101 new->e2di_nblock = bswap32(old->e2di_nblock);
102 new->e2di_flags = bswap32(old->e2di_flags);
103 new->e2di_version = bswap32(old->e2di_version);
104 new->e2di_gen = bswap32(old->e2di_gen);
105 new->e2di_facl = bswap32(old->e2di_facl);
106 new->e2di_size_high = bswap32(old->e2di_size_high);
107 new->e2di_nblock_high = bswap16(old->e2di_nblock_high);
108 new->e2di_facl_high = bswap16(old->e2di_facl_high);
109 new->e2di_uid_high = bswap16(old->e2di_uid_high);
110 new->e2di_gid_high = bswap16(old->e2di_gid_high);
111 new->e2di_checksum_low = bswap16(old->e2di_checksum_low);
112
113 /*
114 * Following fields are only supported for inode sizes bigger
115 * than the old ext2 one
116 */
117 if (isize == EXT2_REV0_DINODE_SIZE)
118 return;
119
120 new->e2di_extra_isize = bswap16(old->e2di_extra_isize);
121 new->e2di_checksum_high = bswap16(old->e2di_checksum_high);
122
123 /* Following fields are ext4, might not be actually present */
124 if (EXT2_DINODE_FITS(new, e2di_ctime_extra, isize))
125 new->e2di_ctime_extra = bswap32(old->e2di_ctime_extra);
126 if (EXT2_DINODE_FITS(new, e2di_mtime_extra, isize))
127 new->e2di_mtime_extra = bswap32(old->e2di_mtime_extra);
128 if (EXT2_DINODE_FITS(new, e2di_atime_extra, isize))
129 new->e2di_atime_extra = bswap32(old->e2di_atime_extra);
130 if (EXT2_DINODE_FITS(new, e2di_crtime, isize))
131 new->e2di_crtime = bswap32(old->e2di_crtime);
132 if (EXT2_DINODE_FITS(new, e2di_crtime_extra, isize))
133 new->e2di_crtime_extra = bswap32(old->e2di_crtime_extra);
134 if (EXT2_DINODE_FITS(new, e2di_version_high, isize))
135 new->e2di_version_high = bswap32(old->e2di_version_high);
136 if (EXT2_DINODE_FITS(new, e2di_projid, isize))
137 new->e2di_projid = bswap32(old->e2di_projid);
138 }
139 #endif
140