1 /*
2 * e2undo.c - Replay an undo log onto an ext2/3/4 filesystem
3 *
4 * Copyright IBM Corporation, 2007
5 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
6 *
7 * %Begin-Header%
8 * This file may be redistributed under the terms of the GNU Public
9 * License.
10 * %End-Header%
11 */
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #ifdef HAVE_GETOPT_H
16 #include <getopt.h>
17 #endif
18 #include <fcntl.h>
19 #if HAVE_ERRNO_H
20 #include <errno.h>
21 #endif
22 #include "ext2fs/tdb.h"
23 #include "ext2fs/ext2fs.h"
24 #include "nls-enable.h"
25
26 unsigned char mtime_key[] = "filesystem MTIME";
27 unsigned char uuid_key[] = "filesystem UUID";
28 unsigned char blksize_key[] = "filesystem BLKSIZE";
29
30 char *prg_name;
31
usage(char * prg_name)32 static void usage(char *prg_name)
33 {
34 fprintf(stderr,
35 _("Usage: %s <transaction file> <filesystem>\n"), prg_name);
36 exit(1);
37
38 }
39
check_filesystem(TDB_CONTEXT * tdb,io_channel channel)40 static int check_filesystem(TDB_CONTEXT *tdb, io_channel channel)
41 {
42 __u32 s_mtime;
43 __u8 s_uuid[16];
44 errcode_t retval;
45 TDB_DATA tdb_key, tdb_data;
46 struct ext2_super_block super;
47
48 io_channel_set_blksize(channel, SUPERBLOCK_OFFSET);
49 retval = io_channel_read_blk(channel, 1, -SUPERBLOCK_SIZE, &super);
50 if (retval) {
51 com_err(prg_name,
52 retval, _("Failed to read the file system data \n"));
53 return retval;
54 }
55
56 tdb_key.dptr = mtime_key;
57 tdb_key.dsize = sizeof(mtime_key);
58 tdb_data = tdb_fetch(tdb, tdb_key);
59 if (!tdb_data.dptr) {
60 retval = EXT2_ET_TDB_SUCCESS + tdb_error(tdb);
61 com_err(prg_name, retval,
62 _("Failed tdb_fetch %s\n"), tdb_errorstr(tdb));
63 return retval;
64 }
65
66 s_mtime = *(__u32 *)tdb_data.dptr;
67 if (super.s_mtime != s_mtime) {
68
69 com_err(prg_name, 0,
70 _("The file system Mount time didn't match %u\n"),
71 s_mtime);
72
73 return -1;
74 }
75
76
77 tdb_key.dptr = uuid_key;
78 tdb_key.dsize = sizeof(uuid_key);
79 tdb_data = tdb_fetch(tdb, tdb_key);
80 if (!tdb_data.dptr) {
81 retval = EXT2_ET_TDB_SUCCESS + tdb_error(tdb);
82 com_err(prg_name, retval,
83 _("Failed tdb_fetch %s\n"), tdb_errorstr(tdb));
84 return retval;
85 }
86 memcpy(s_uuid, tdb_data.dptr, sizeof(s_uuid));
87 if (memcmp(s_uuid, super.s_uuid, sizeof(s_uuid))) {
88 com_err(prg_name, 0,
89 _("The file system UUID didn't match \n"));
90 return -1;
91 }
92
93 return 0;
94 }
95
set_blk_size(TDB_CONTEXT * tdb,io_channel channel)96 static int set_blk_size(TDB_CONTEXT *tdb, io_channel channel)
97 {
98 int block_size;
99 errcode_t retval;
100 TDB_DATA tdb_key, tdb_data;
101
102 tdb_key.dptr = blksize_key;
103 tdb_key.dsize = sizeof(blksize_key);
104 tdb_data = tdb_fetch(tdb, tdb_key);
105 if (!tdb_data.dptr) {
106 retval = EXT2_ET_TDB_SUCCESS + tdb_error(tdb);
107 com_err(prg_name, retval,
108 _("Failed tdb_fetch %s\n"), tdb_errorstr(tdb));
109 return retval;
110 }
111
112 block_size = *(int *)tdb_data.dptr;
113 #ifdef DEBUG
114 printf("Block size %d\n", block_size);
115 #endif
116 io_channel_set_blksize(channel, block_size);
117
118 return 0;
119 }
120
main(int argc,char * argv[])121 int main(int argc, char *argv[])
122 {
123 int c,force = 0;
124 TDB_CONTEXT *tdb;
125 TDB_DATA key, data;
126 io_channel channel;
127 errcode_t retval;
128 int mount_flags;
129 unsigned long blk_num;
130 char *device_name, *tdb_file;
131 io_manager manager = unix_io_manager;
132
133 #ifdef ENABLE_NLS
134 setlocale(LC_MESSAGES, "");
135 setlocale(LC_CTYPE, "");
136 bindtextdomain(NLS_CAT_NAME, LOCALEDIR);
137 textdomain(NLS_CAT_NAME);
138 #endif
139 add_error_table(&et_ext2_error_table);
140
141 prg_name = argv[0];
142 while((c = getopt(argc, argv, "f")) != EOF) {
143 switch (c) {
144 case 'f':
145 force = 1;
146 break;
147 default:
148 usage(prg_name);
149 }
150 }
151
152 if (argc != optind+2)
153 usage(prg_name);
154
155 tdb_file = argv[optind];
156 device_name = argv[optind+1];
157
158 tdb = tdb_open(tdb_file, 0, 0, O_RDONLY, 0600);
159
160 if (!tdb) {
161 com_err(prg_name, errno,
162 _("Failed tdb_open %s\n"), tdb_file);
163 exit(1);
164 }
165
166 retval = ext2fs_check_if_mounted(device_name, &mount_flags);
167 if (retval) {
168 com_err(prg_name, retval, _("Error while determining whether "
169 "%s is mounted.\n"), device_name);
170 exit(1);
171 }
172
173 if (mount_flags & EXT2_MF_MOUNTED) {
174 com_err(prg_name, retval, _("e2undo should only be run on "
175 "unmounted file system\n"));
176 exit(1);
177 }
178
179 retval = manager->open(device_name,
180 IO_FLAG_EXCLUSIVE | IO_FLAG_RW, &channel);
181 if (retval) {
182 com_err(prg_name, retval,
183 _("Failed to open %s\n"), device_name);
184 exit(1);
185 }
186
187 if (!force && check_filesystem(tdb, channel)) {
188 exit(1);
189 }
190
191 if (set_blk_size(tdb, channel)) {
192 exit(1);
193 }
194
195 for (key = tdb_firstkey(tdb); key.dptr; key = tdb_nextkey(tdb, key)) {
196 if (!strcmp((char *) key.dptr, (char *) mtime_key) ||
197 !strcmp((char *) key.dptr, (char *) uuid_key) ||
198 !strcmp((char *) key.dptr, (char *) blksize_key)) {
199 continue;
200 }
201
202 data = tdb_fetch(tdb, key);
203 if (!data.dptr) {
204 com_err(prg_name, 0,
205 _("Failed tdb_fetch %s\n"), tdb_errorstr(tdb));
206 exit(1);
207 }
208 blk_num = *(unsigned long *)key.dptr;
209 printf(_("Replayed transaction of size %zd at location %ld\n"),
210 data.dsize, blk_num);
211 retval = io_channel_write_blk(channel, blk_num,
212 -data.dsize, data.dptr);
213 if (retval == -1) {
214 com_err(prg_name, retval,
215 _("Failed write %s\n"),
216 strerror(errno));
217 exit(1);
218 }
219 }
220 io_channel_close(channel);
221 tdb_close(tdb);
222
223 return 0;
224 }
225