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 (at) 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 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 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 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 } 120 121 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
