1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Keith Muller of the University of California, San Diego and Lance 9 * Visser of Convex Computer Corporation. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)dd.c 8.5 (Berkeley) 4/2/94 36 * $FreeBSD: head/bin/dd/dd.c 341257 2018-11-29 19:28:01Z sobomax $ 37 */ 38 39 #include <sys/param.h> 40 #include <sys/stat.h> 41 #ifndef BOOTSTRAPPING 42 #include <sys/conf.h> 43 #include <sys/device.h> 44 #include <sys/filio.h> 45 #endif 46 47 #include <ctype.h> 48 #include <err.h> 49 #include <errno.h> 50 #include <fcntl.h> 51 #include <locale.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <signal.h> 56 #include <time.h> 57 #include <unistd.h> 58 59 #include "dd.h" 60 #include "extern.h" 61 62 #ifndef SIGINFO 63 #define SIGINFO SIGUSR1 64 #endif 65 66 static void dd_close(void); 67 static void dd_in(void); 68 static void getfdtype(IO *); 69 static int parity(u_char); 70 static void setup(void); 71 static void speed_limit(void); 72 static void swapbytes(void *, size_t); 73 74 IO in, out; /* input/output state */ 75 STAT st; /* statistics */ 76 void (*cfunc)(void); /* conversion function */ 77 uintmax_t cpy_cnt; /* # of blocks to copy */ 78 u_int ddflags = 0; /* conversion options */ 79 size_t cbsz; /* conversion block size */ 80 uintmax_t files_cnt = 1; /* # of files to copy */ 81 const u_char *ctab; /* conversion table */ 82 char fill_char; /* Character to fill with if defined */ 83 size_t speed = 0; /* maximum speed, in bytes per second */ 84 volatile sig_atomic_t need_summary; 85 volatile sig_atomic_t need_progress; 86 87 static off_t pending = 0; /* pending seek if sparse */ 88 89 int 90 main(int argc __unused, char *argv[]) 91 { 92 /* SIGALRM every second, if needed */ 93 struct itimerval itv = { { 1, 0 }, { 1, 0 } }; 94 95 setlocale(LC_CTYPE, ""); 96 jcl(argv); 97 setup(); 98 99 signal(SIGINFO, siginfo_handler); 100 if (ddflags & C_PROGRESS) { 101 signal(SIGALRM, sigalarm_handler); 102 setitimer(ITIMER_REAL, &itv, NULL); 103 } 104 signal(SIGINT, terminate); 105 106 atexit(summary); 107 108 while (files_cnt--) 109 dd_in(); 110 111 dd_close(); 112 /* 113 * Some devices such as cfi(4) may perform significant amounts 114 * of work when a write descriptor is closed. Close the out 115 * descriptor explicitly so that the summary handler (called 116 * from an atexit() hook) includes this work. 117 */ 118 close(out.fd); 119 exit(0); 120 } 121 122 static int 123 parity(u_char c) 124 { 125 int i; 126 127 i = c ^ (c >> 1) ^ (c >> 2) ^ (c >> 3) ^ 128 (c >> 4) ^ (c >> 5) ^ (c >> 6) ^ (c >> 7); 129 return (i & 1); 130 } 131 132 static void 133 setup(void) 134 { 135 u_int cnt; 136 137 if (in.name == NULL) { 138 in.name = "stdin"; 139 in.fd = STDIN_FILENO; 140 } else { 141 in.fd = open(in.name, O_RDONLY, 0); 142 if (in.fd == -1) 143 err(1, "%s", in.name); 144 } 145 146 getfdtype(&in); 147 148 if (files_cnt > 1 && !(in.flags & ISTAPE)) 149 errx(1, "files is not supported for non-tape devices"); 150 151 if (out.name == NULL) { 152 /* No way to check for read access here. */ 153 out.fd = STDOUT_FILENO; 154 out.name = "stdout"; 155 } else { 156 #define OFLAGS \ 157 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 158 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 159 /* 160 * May not have read access, so try again with write only. 161 * Without read we may have a problem if output also does 162 * not support seeks. 163 */ 164 if (out.fd == -1) { 165 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 166 out.flags |= NOREAD; 167 } 168 if (out.fd == -1) 169 err(1, "%s", out.name); 170 } 171 172 getfdtype(&out); 173 174 /* 175 * Allocate space for the input and output buffers. If not doing 176 * record oriented I/O, only need a single buffer. 177 */ 178 if (!(ddflags & (C_BLOCK | C_UNBLOCK))) { 179 if ((in.db = malloc((size_t)out.dbsz + in.dbsz - 1)) == NULL) 180 err(1, "input buffer"); 181 out.db = in.db; 182 } else if ((in.db = malloc(MAX((size_t)in.dbsz, cbsz) + cbsz)) == NULL || 183 (out.db = malloc(out.dbsz + cbsz)) == NULL) { 184 err(1, "output buffer"); 185 } 186 187 /* dbp is the first free position in each buffer. */ 188 in.dbp = in.db; 189 out.dbp = out.db; 190 191 /* Position the input/output streams. */ 192 if (in.offset) 193 pos_in(); 194 if (out.offset) 195 pos_out(); 196 197 /* 198 * Truncate the output file. If it fails on a type of output file 199 * that it should _not_ fail on, error out. 200 */ 201 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK) && 202 out.flags & ISTRUNC) 203 if (ftruncate(out.fd, out.offset * out.dbsz) == -1) 204 err(1, "truncating %s", out.name); 205 206 if (ddflags & (C_LCASE | C_UCASE | C_ASCII | C_EBCDIC | C_PARITY)) { 207 if (ctab != NULL) { 208 for (cnt = 0; cnt <= 0377; ++cnt) 209 casetab[cnt] = ctab[cnt]; 210 } else { 211 for (cnt = 0; cnt <= 0377; ++cnt) 212 casetab[cnt] = cnt; 213 } 214 if ((ddflags & C_PARITY) && !(ddflags & C_ASCII)) { 215 /* 216 * If the input is not EBCDIC, and we do parity 217 * processing, strip input parity. 218 */ 219 for (cnt = 200; cnt <= 0377; ++cnt) 220 casetab[cnt] = casetab[cnt & 0x7f]; 221 } 222 if (ddflags & C_LCASE) { 223 for (cnt = 0; cnt <= 0377; ++cnt) 224 casetab[cnt] = tolower(casetab[cnt]); 225 } else if (ddflags & C_UCASE) { 226 for (cnt = 0; cnt <= 0377; ++cnt) 227 casetab[cnt] = toupper(casetab[cnt]); 228 } 229 if ((ddflags & C_PARITY)) { 230 /* 231 * This should strictly speaking be a no-op, but I 232 * wonder what funny LANG settings could get us. 233 */ 234 for (cnt = 0; cnt <= 0377; ++cnt) 235 casetab[cnt] = casetab[cnt] & 0x7f; 236 } 237 if ((ddflags & C_PARSET)) { 238 for (cnt = 0; cnt <= 0377; ++cnt) 239 casetab[cnt] = casetab[cnt] | 0x80; 240 } 241 if ((ddflags & C_PAREVEN)) { 242 for (cnt = 0; cnt <= 0377; ++cnt) 243 if (parity(casetab[cnt])) 244 casetab[cnt] = casetab[cnt] | 0x80; 245 } 246 if ((ddflags & C_PARODD)) { 247 for (cnt = 0; cnt <= 0377; ++cnt) 248 if (!parity(casetab[cnt])) 249 casetab[cnt] = casetab[cnt] | 0x80; 250 } 251 252 ctab = casetab; 253 } 254 255 if (clock_gettime(CLOCK_MONOTONIC, &st.start)) 256 err(1, "clock_gettime"); 257 } 258 259 static void 260 getfdtype(IO *io) 261 { 262 struct stat sb; 263 #ifndef BOOTSTRAPPING 264 int type; 265 #endif 266 267 if (fstat(io->fd, &sb) == -1) 268 err(1, "%s", io->name); 269 if (S_ISREG(sb.st_mode)) 270 io->flags |= ISTRUNC; 271 if (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode)) { 272 #ifdef BOOTSTRAPPING 273 io->flags |= ISSEEK; /* assume D_DISK|D_MEM in btools */ 274 #else 275 if (ioctl(io->fd, FIODTYPE, &type) == -1) { 276 err(1, "%s", io->name); 277 } else { 278 if (type & D_TAPE) 279 io->flags |= ISTAPE; 280 else if (type & (D_DISK | D_MEM)) 281 io->flags |= ISSEEK; 282 if (S_ISCHR(sb.st_mode) && (type & D_TAPE) == 0) 283 io->flags |= ISCHR; 284 } 285 #endif 286 return; 287 } 288 errno = 0; 289 if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 290 io->flags |= ISPIPE; 291 else 292 io->flags |= ISSEEK; 293 } 294 295 /* 296 * Limit the speed by adding a delay before every block read. 297 * The delay (t_usleep) is equal to the time computed from block 298 * size and the specified speed limit (t_target) minus the time 299 * spent on actual read and write operations (t_io). 300 */ 301 static void 302 speed_limit(void) 303 { 304 static double t_prev, t_usleep; 305 double t_now, t_io, t_target; 306 307 t_now = secs_elapsed(); 308 t_io = t_now - t_prev - t_usleep; 309 t_target = (double)in.dbsz / (double)speed; 310 t_usleep = t_target - t_io; 311 if (t_usleep > 0) 312 usleep(t_usleep * 1000000); 313 else 314 t_usleep = 0; 315 t_prev = t_now; 316 } 317 318 static void 319 swapbytes(void *v, size_t len) 320 { 321 unsigned char *p = v; 322 unsigned char t; 323 324 while (len > 1) { 325 t = p[0]; 326 p[0] = p[1]; 327 p[1] = t; 328 p += 2; 329 len -= 2; 330 } 331 } 332 333 static void 334 dd_in(void) 335 { 336 ssize_t n; 337 338 for (;;) { 339 switch (cpy_cnt) { 340 case -1: /* count=0 was specified */ 341 return; 342 case 0: 343 break; 344 default: 345 if (st.in_full + st.in_part >= (uintmax_t)cpy_cnt) 346 return; 347 break; 348 } 349 350 if (speed > 0) 351 speed_limit(); 352 353 /* 354 * Zero the buffer first if sync; if doing block operations, 355 * use spaces. 356 */ 357 if (ddflags & C_SYNC) { 358 if (ddflags & C_FILL) 359 memset(in.dbp, fill_char, in.dbsz); 360 else if (ddflags & (C_BLOCK | C_UNBLOCK)) 361 memset(in.dbp, ' ', in.dbsz); 362 else 363 memset(in.dbp, 0, in.dbsz); 364 } 365 366 n = read(in.fd, in.dbp, in.dbsz); 367 if (n == 0) { 368 in.dbrcnt = 0; 369 return; 370 } 371 372 /* Read error. */ 373 if (n == -1) { 374 /* 375 * If noerror not specified, die. POSIX requires that 376 * the warning message be followed by an I/O display. 377 */ 378 if (!(ddflags & C_NOERROR)) 379 err(1, "%s", in.name); 380 warn("%s", in.name); 381 summary(); 382 383 /* 384 * If it's a seekable file descriptor, seek past the 385 * error. If your OS doesn't do the right thing for 386 * raw disks this section should be modified to re-read 387 * in sector size chunks. 388 */ 389 if (in.flags & ISSEEK && 390 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 391 warn("%s", in.name); 392 393 /* If sync not specified, omit block and continue. */ 394 if (!(ddflags & C_SYNC)) 395 continue; 396 397 /* Read errors count as full blocks. */ 398 in.dbcnt += in.dbrcnt = in.dbsz; 399 ++st.in_full; 400 401 /* Handle full input blocks. */ 402 } else if (n == in.dbsz) { 403 in.dbcnt += in.dbrcnt = n; 404 ++st.in_full; 405 406 /* Handle partial input blocks. */ 407 } else { 408 /* If sync, use the entire block. */ 409 if (ddflags & C_SYNC) 410 in.dbcnt += in.dbrcnt = in.dbsz; 411 else 412 in.dbcnt += in.dbrcnt = n; 413 ++st.in_part; 414 } 415 416 /* 417 * POSIX states that if bs is set and no other conversions 418 * than noerror, notrunc or sync are specified, the block 419 * is output without buffering as it is read. 420 */ 421 if ((ddflags & ~(C_NOERROR | C_NOTRUNC | C_SYNC)) == C_BS) { 422 out.dbcnt = in.dbcnt; 423 dd_out(1); 424 in.dbcnt = 0; 425 continue; 426 } 427 428 if (ddflags & C_SWAB) { 429 if ((n = in.dbrcnt) & 1) { 430 ++st.swab; 431 --n; 432 } 433 swapbytes(in.dbp, (size_t)n); 434 } 435 436 in.dbp += in.dbrcnt; 437 (*cfunc)(); 438 if (need_summary) 439 summary(); 440 if (need_progress) 441 progress(); 442 } 443 } 444 445 /* 446 * Clean up any remaining I/O and flush output. If necessary, the output file 447 * is truncated. 448 */ 449 static void 450 dd_close(void) 451 { 452 if (cfunc == def) 453 def_close(); 454 else if (cfunc == block) 455 block_close(); 456 else if (cfunc == unblock) 457 unblock_close(); 458 if (ddflags & C_OSYNC && out.dbcnt && out.dbcnt < out.dbsz) { 459 if (ddflags & C_FILL) 460 memset(out.dbp, fill_char, out.dbsz - out.dbcnt); 461 else if (ddflags & (C_BLOCK | C_UNBLOCK)) 462 memset(out.dbp, ' ', out.dbsz - out.dbcnt); 463 else 464 memset(out.dbp, 0, out.dbsz - out.dbcnt); 465 out.dbcnt = out.dbsz; 466 } 467 if (out.dbcnt || pending) 468 dd_out(1); 469 470 /* 471 * If the file ends with a hole, ftruncate it to extend its size 472 * up to the end of the hole (without having to write any data). 473 */ 474 if (out.seek_offset > 0 && (out.flags & ISTRUNC)) { 475 if (ftruncate(out.fd, out.seek_offset) == -1) 476 err(1, "truncating %s", out.name); 477 } 478 } 479 480 void 481 dd_out(int force) 482 { 483 u_char *outp; 484 size_t cnt, n; 485 ssize_t nw; 486 static int warned; 487 int sparse; 488 489 /* 490 * Write one or more blocks out. The common case is writing a full 491 * output block in a single write; increment the full block stats. 492 * Otherwise, we're into partial block writes. If a partial write, 493 * and it's a character device, just warn. If a tape device, quit. 494 * 495 * The partial writes represent two cases. 1: Where the input block 496 * was less than expected so the output block was less than expected. 497 * 2: Where the input block was the right size but we were forced to 498 * write the block in multiple chunks. The original versions of dd(1) 499 * never wrote a block in more than a single write, so the latter case 500 * never happened. 501 * 502 * One special case is if we're forced to do the write -- in that case 503 * we play games with the buffer size, and it's usually a partial write. 504 */ 505 outp = out.db; 506 507 /* 508 * If force, first try to write all pending data, else try to write 509 * just one block. Subsequently always write data one full block at 510 * a time at most. 511 */ 512 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 513 cnt = n; 514 do { 515 sparse = 0; 516 if (ddflags & C_SPARSE) { 517 /* Is buffer sparse? */ 518 sparse = BISZERO(outp, cnt); 519 } 520 if (sparse && !force) { 521 pending += cnt; 522 nw = cnt; 523 } else { 524 if (pending != 0) { 525 /* 526 * Seek past hole. Note that we need to record the 527 * reached offset, because we might have no more data 528 * to write, in which case we'll need to call 529 * ftruncate to extend the file size. 530 */ 531 out.seek_offset = lseek(out.fd, pending, SEEK_CUR); 532 if (out.seek_offset == -1) 533 err(2, "%s: seek error creating sparse file", 534 out.name); 535 pending = 0; 536 } 537 if (cnt) { 538 nw = write(out.fd, outp, cnt); 539 out.seek_offset = 0; 540 } else { 541 return; 542 } 543 } 544 545 if (nw <= 0) { 546 if (nw == 0) 547 errx(1, "%s: end of device", out.name); 548 if (errno != EINTR) 549 err(1, "%s", out.name); 550 nw = 0; 551 } 552 553 outp += nw; 554 st.bytes += nw; 555 556 if ((size_t)nw == n && n == (size_t)out.dbsz) 557 ++st.out_full; 558 else 559 ++st.out_part; 560 561 if ((size_t) nw != cnt) { 562 if (out.flags & ISTAPE) 563 errx(1, "%s: short write on tape device", 564 out.name); 565 if (out.flags & ISCHR && !warned) { 566 warned = 1; 567 warnx("%s: short write on character device", 568 out.name); 569 } 570 } 571 572 cnt -= nw; 573 } while (cnt != 0); 574 575 if ((out.dbcnt -= n) < out.dbsz) 576 break; 577 } 578 579 /* Reassemble the output block. */ 580 if (out.dbcnt) 581 memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 582 out.dbp = out.db + out.dbcnt; 583 } 584