1 /* $OpenBSD: fsirand.c,v 1.43 2020/06/20 07:49:04 otto Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Todd C. Miller <millert@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/param.h> /* DEV_BSIZE */ 20 #include <sys/disklabel.h> 21 #include <sys/ioctl.h> 22 #include <sys/dkio.h> 23 #include <sys/resource.h> 24 #include <sys/time.h> 25 26 #include <ufs/ffs/fs.h> 27 #include <ufs/ufs/dinode.h> 28 29 #include <err.h> 30 #include <errno.h> 31 #include <fcntl.h> 32 #include <stdio.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include <unistd.h> 36 #include <util.h> 37 38 void usage(int); 39 int fsirand(char *); 40 41 extern char *__progname; 42 43 int printonly = 0, force = 0, ignorelabel = 0; 44 45 /* 46 * Possible locations for the superblock. 47 */ 48 static const int sbtry[] = SBLOCKSEARCH; 49 50 int 51 main(int argc, char *argv[]) 52 { 53 int n, ex = 0; 54 struct rlimit rl; 55 56 while ((n = getopt(argc, argv, "bfp")) != -1) { 57 switch (n) { 58 case 'b': 59 ignorelabel = 1; 60 break; 61 case 'p': 62 printonly = 1; 63 break; 64 case 'f': 65 force = 1; 66 break; 67 default: 68 usage(1); 69 } 70 } 71 if (argc - optind < 1) 72 usage(1); 73 74 /* Increase our data size to the max */ 75 if (getrlimit(RLIMIT_DATA, &rl) == 0) { 76 rl.rlim_cur = rl.rlim_max; 77 if (setrlimit(RLIMIT_DATA, &rl) == -1) 78 warn("Can't set resource limit to max data size"); 79 } else 80 warn("Can't get resource limit for data size"); 81 82 for (n = optind; n < argc; n++) { 83 if (argc - optind != 1) 84 (void)puts(argv[n]); 85 ex += fsirand(argv[n]); 86 if (n < argc - 1) 87 putchar('\n'); 88 } 89 90 exit(ex); 91 } 92 93 int 94 fsirand(char *device) 95 { 96 struct ufs1_dinode *dp1 = NULL; 97 struct ufs2_dinode *dp2 = NULL; 98 static char *inodebuf; 99 size_t ibufsize, isize; 100 struct fs *sblock, *tmpsblock; 101 ino_t inumber; 102 daddr_t sblockloc, dblk; 103 char sbuf[SBSIZE], sbuftmp[SBSIZE]; 104 int devfd, n, i; 105 u_int cg; 106 char *devpath, *ib; 107 u_int32_t bsize = DEV_BSIZE; 108 struct disklabel label; 109 110 if ((devfd = opendev(device, printonly ? O_RDONLY : O_RDWR, 111 0, &devpath)) == -1) { 112 warn("Can't open %s", devpath); 113 return (1); 114 } 115 116 /* Get block size (usually 512) from disklabel if possible */ 117 if (!ignorelabel) { 118 if (ioctl(devfd, DIOCGDINFO, &label) == -1) 119 warn("Can't read disklabel, using sector size of %d", 120 bsize); 121 else 122 bsize = label.d_secsize; 123 } 124 125 if (pledge("stdio", NULL) == -1) 126 err(1, "pledge"); 127 128 /* Read in master superblock */ 129 (void)memset(&sbuf, 0, sizeof(sbuf)); 130 sblock = (struct fs *)&sbuf; 131 132 for (i = 0; sbtry[i] != -1; i++) { 133 sblockloc = sbtry[i]; 134 135 if (lseek(devfd, sblockloc, SEEK_SET) == -1) { 136 warn("Can't seek to superblock (%lld) on %s", 137 (long long)sblockloc, devpath); 138 return (1); 139 } 140 141 if ((n = read(devfd, sblock, SBSIZE)) != SBSIZE) { 142 warnx("Can't read superblock on %s: %s", devpath, 143 (n < SBSIZE) ? "short read" : strerror(errno)); 144 return (1); 145 } 146 147 /* Find a suitable superblock */ 148 if (sblock->fs_magic != FS_UFS1_MAGIC && 149 sblock->fs_magic != FS_UFS2_MAGIC) 150 continue; /* Not a superblock */ 151 152 /* 153 * Do not look for an FFS1 file system at SBLOCK_UFS2. 154 * Doing so will find the wrong super-block for file 155 * systems with 64k block size. 156 */ 157 if (sblock->fs_magic == FS_UFS1_MAGIC && 158 sbtry[i] == SBLOCK_UFS2) 159 continue; 160 161 if (sblock->fs_magic == FS_UFS2_MAGIC && 162 sblock->fs_sblockloc != sbtry[i]) 163 continue; /* Not a superblock */ 164 165 break; 166 } 167 168 if (sbtry[i] == -1) { 169 warnx("Cannot find file system superblock"); 170 return (1); 171 } 172 173 /* Simple sanity checks on the superblock */ 174 if (sblock->fs_sbsize > SBSIZE) { 175 warnx("Superblock size is preposterous"); 176 return (1); 177 } 178 179 if (sblock->fs_postblformat == FS_42POSTBLFMT) { 180 warnx("Filesystem format is too old, sorry"); 181 return (1); 182 } 183 184 if (!force && !printonly && sblock->fs_clean != FS_ISCLEAN) { 185 warnx("Filesystem is not clean, fsck %s first.", devpath); 186 return (1); 187 } 188 189 /* Make sure backup superblocks are sane. */ 190 tmpsblock = (struct fs *)&sbuftmp; 191 for (cg = 0; cg < sblock->fs_ncg; cg++) { 192 dblk = fsbtodb(sblock, cgsblock(sblock, cg)); 193 if (lseek(devfd, (off_t)dblk * bsize, SEEK_SET) == -1) { 194 warn("Can't seek to %lld", (long long)dblk * bsize); 195 return (1); 196 } else if ((n = read(devfd, tmpsblock, SBSIZE)) != SBSIZE) { 197 warn("Can't read backup superblock %d on %s: %s", 198 cg + 1, devpath, (n < SBSIZE) ? "short read" 199 : strerror(errno)); 200 return (1); 201 } 202 if (tmpsblock->fs_magic != FS_UFS1_MAGIC && 203 tmpsblock->fs_magic != FS_UFS2_MAGIC) { 204 warnx("Bad magic number in backup superblock %d on %s", 205 cg + 1, devpath); 206 return (1); 207 } 208 if (tmpsblock->fs_sbsize > SBSIZE) { 209 warnx("Size of backup superblock %d on %s is preposterous", 210 cg + 1, devpath); 211 return (1); 212 } 213 } 214 215 /* XXX - should really cap buffer at 512kb or so */ 216 if (sblock->fs_magic == FS_UFS1_MAGIC) 217 isize = sizeof(struct ufs1_dinode); 218 else 219 isize = sizeof(struct ufs2_dinode); 220 221 if ((ib = reallocarray(inodebuf, sblock->fs_ipg, isize)) == NULL) 222 errx(1, "Can't allocate memory for inode buffer"); 223 inodebuf = ib; 224 ibufsize = sblock->fs_ipg * isize; 225 226 if (printonly && (sblock->fs_id[0] || sblock->fs_id[1])) { 227 if (sblock->fs_inodefmt >= FS_44INODEFMT && sblock->fs_id[0]) { 228 time_t t = sblock->fs_id[0]; /* XXX 2038 */ 229 (void)printf("%s was randomized on %s", devpath, 230 ctime(&t)); 231 } 232 (void)printf("fsid: %x %x\n", sblock->fs_id[0], 233 sblock->fs_id[1]); 234 } 235 236 /* Randomize fs_id unless old 4.2BSD filesystem */ 237 if ((sblock->fs_inodefmt >= FS_44INODEFMT) && !printonly) { 238 /* Randomize fs_id and write out new sblock and backups */ 239 sblock->fs_id[0] = (u_int32_t)time(NULL); 240 sblock->fs_id[1] = arc4random(); 241 242 if (lseek(devfd, SBOFF, SEEK_SET) == -1) { 243 warn("Can't seek to superblock (%lld) on %s", 244 (long long)SBOFF, devpath); 245 return (1); 246 } 247 if ((n = write(devfd, sblock, SBSIZE)) != SBSIZE) { 248 warn("Can't write superblock on %s: %s", devpath, 249 (n < SBSIZE) ? "short write" : strerror(errno)); 250 return (1); 251 } 252 } 253 254 /* For each cylinder group, randomize inodes and update backup sblock */ 255 for (cg = 0, inumber = 0; cg < sblock->fs_ncg; cg++) { 256 /* Update superblock if appropriate */ 257 if ((sblock->fs_inodefmt >= FS_44INODEFMT) && !printonly) { 258 dblk = fsbtodb(sblock, cgsblock(sblock, cg)); 259 if (lseek(devfd, (off_t)dblk * bsize, 260 SEEK_SET) == -1) { 261 warn("Can't seek to %lld", 262 (long long)dblk * bsize); 263 return (1); 264 } else if ((n = write(devfd, sblock, SBSIZE)) != 265 SBSIZE) { 266 warn("Can't read backup superblock %d on %s: %s", 267 cg + 1, devpath, (n < SBSIZE) ? "short write" 268 : strerror(errno)); 269 return (1); 270 } 271 } 272 273 /* Read in inodes, then print or randomize generation nums */ 274 dblk = fsbtodb(sblock, ino_to_fsba(sblock, inumber)); 275 if (lseek(devfd, (off_t)dblk * bsize, SEEK_SET) == -1) { 276 warn("Can't seek to %lld", (long long)dblk * bsize); 277 return (1); 278 } else if ((n = read(devfd, inodebuf, ibufsize)) != ibufsize) { 279 warnx("Can't read inodes: %s", 280 (n < ibufsize) ? "short read" : strerror(errno)); 281 return (1); 282 } 283 284 for (n = 0; n < sblock->fs_ipg; n++, inumber++) { 285 if (sblock->fs_magic == FS_UFS1_MAGIC) 286 dp1 = &((struct ufs1_dinode *)inodebuf)[n]; 287 else 288 dp2 = &((struct ufs2_dinode *)inodebuf)[n]; 289 if (inumber >= ROOTINO) { 290 if (printonly) 291 (void)printf("ino %llu gen %x\n", 292 (unsigned long long)inumber, 293 sblock->fs_magic == FS_UFS1_MAGIC ? 294 dp1->di_gen : dp2->di_gen); 295 else if (sblock->fs_magic == FS_UFS1_MAGIC) 296 dp1->di_gen = arc4random(); 297 else 298 dp2->di_gen = arc4random(); 299 } 300 } 301 302 /* Write out modified inodes */ 303 if (!printonly) { 304 if (lseek(devfd, (off_t)dblk * bsize, SEEK_SET) == -1) { 305 warn("Can't seek to %lld", 306 (long long)dblk * bsize); 307 return (1); 308 } else if ((n = write(devfd, inodebuf, ibufsize)) != 309 ibufsize) { 310 warnx("Can't write inodes: %s", 311 (n != ibufsize) ? "short write" : 312 strerror(errno)); 313 return (1); 314 } 315 } 316 } 317 (void)close(devfd); 318 319 return(0); 320 } 321 322 void 323 usage(int ex) 324 { 325 (void)fprintf(stderr, "usage: %s [-bfp] special ...\n", 326 __progname); 327 exit(ex); 328 } 329