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Diffstat (limited to 'bin/dd/dd.c')
| -rw-r--r-- | bin/dd/dd.c | 644 |
1 files changed, 644 insertions, 0 deletions
diff --git a/bin/dd/dd.c b/bin/dd/dd.c new file mode 100644 index 000000000000..c43645fa0073 --- /dev/null +++ b/bin/dd/dd.c @@ -0,0 +1,644 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1991, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Keith Muller of the University of California, San Diego and Lance + * Visser of Convex Computer Corporation. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if 0 +#ifndef lint +static char const copyright[] = +"@(#) Copyright (c) 1991, 1993, 1994\n\ + The Regents of the University of California. All rights reserved.\n"; +#endif /* not lint */ + +#ifndef lint +static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94"; +#endif /* not lint */ +#endif +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/stat.h> +#include <sys/capsicum.h> +#include <sys/conf.h> +#include <sys/disklabel.h> +#include <sys/filio.h> +#include <sys/mtio.h> +#include <sys/time.h> + +#include <assert.h> +#include <capsicum_helpers.h> +#include <ctype.h> +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <inttypes.h> +#include <locale.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <unistd.h> + +#include "dd.h" +#include "extern.h" + +static void dd_close(void); +static void dd_in(void); +static void getfdtype(IO *); +static void setup(void); + +IO in, out; /* input/output state */ +STAT st; /* statistics */ +void (*cfunc)(void); /* conversion function */ +uintmax_t cpy_cnt; /* # of blocks to copy */ +static off_t pending = 0; /* pending seek if sparse */ +uint64_t ddflags = 0; /* conversion options */ +size_t cbsz; /* conversion block size */ +uintmax_t files_cnt = 1; /* # of files to copy */ +const u_char *ctab; /* conversion table */ +char fill_char; /* Character to fill with if defined */ +size_t speed = 0; /* maximum speed, in bytes per second */ +volatile sig_atomic_t need_summary; +volatile sig_atomic_t need_progress; + +int +main(int argc __unused, char *argv[]) +{ + struct itimerval itv = { { 1, 0 }, { 1, 0 } }; /* SIGALARM every second, if needed */ + + (void)setlocale(LC_CTYPE, ""); + jcl(argv); + setup(); + + caph_cache_catpages(); + if (caph_enter() < 0) + err(1, "unable to enter capability mode"); + + (void)signal(SIGINFO, siginfo_handler); + if (ddflags & C_PROGRESS) { + (void)signal(SIGALRM, sigalarm_handler); + setitimer(ITIMER_REAL, &itv, NULL); + } + (void)signal(SIGINT, terminate); + + atexit(summary); + + while (files_cnt--) + dd_in(); + + dd_close(); + /* + * Some devices such as cfi(4) may perform significant amounts + * of work when a write descriptor is closed. Close the out + * descriptor explicitly so that the summary handler (called + * from an atexit() hook) includes this work. + */ + if (close(out.fd) == -1 && errno != EINTR) + err(1, "close"); + exit(0); +} + +static int +parity(u_char c) +{ + int i; + + i = c ^ (c >> 1) ^ (c >> 2) ^ (c >> 3) ^ + (c >> 4) ^ (c >> 5) ^ (c >> 6) ^ (c >> 7); + return (i & 1); +} + +static void +setup(void) +{ + u_int cnt; + int iflags, oflags; + cap_rights_t rights; + unsigned long cmds[] = { FIODTYPE, MTIOCTOP }; + + if (in.name == NULL) { + in.name = "stdin"; + in.fd = STDIN_FILENO; + } else { + iflags = 0; + if (ddflags & C_IDIRECT) + iflags |= O_DIRECT; + in.fd = open(in.name, O_RDONLY | iflags, 0); + if (in.fd == -1) + err(1, "%s", in.name); + } + + getfdtype(&in); + + cap_rights_init(&rights, CAP_READ, CAP_SEEK); + if (caph_rights_limit(in.fd, &rights) == -1) + err(1, "unable to limit capability rights"); + + if (files_cnt > 1 && !(in.flags & ISTAPE)) + errx(1, "files is not supported for non-tape devices"); + + cap_rights_set(&rights, CAP_FTRUNCATE, CAP_IOCTL, CAP_WRITE); + if (ddflags & (C_FDATASYNC | C_FSYNC)) + cap_rights_set(&rights, CAP_FSYNC); + if (out.name == NULL) { + /* No way to check for read access here. */ + out.fd = STDOUT_FILENO; + out.name = "stdout"; + if (ddflags & C_OFSYNC) { + oflags = fcntl(out.fd, F_GETFL); + if (oflags == -1) + err(1, "unable to get fd flags for stdout"); + oflags |= O_FSYNC; + if (fcntl(out.fd, F_SETFL, oflags) == -1) + err(1, "unable to set fd flags for stdout"); + } + } else { + oflags = O_CREAT; + if (!(ddflags & (C_SEEK | C_NOTRUNC))) + oflags |= O_TRUNC; + if (ddflags & C_OFSYNC) + oflags |= O_FSYNC; + if (ddflags & C_ODIRECT) + oflags |= O_DIRECT; + out.fd = open(out.name, O_RDWR | oflags, DEFFILEMODE); + /* + * May not have read access, so try again with write only. + * Without read we may have a problem if output also does + * not support seeks. + */ + if (out.fd == -1) { + out.fd = open(out.name, O_WRONLY | oflags, DEFFILEMODE); + out.flags |= NOREAD; + cap_rights_clear(&rights, CAP_READ); + } + if (out.fd == -1) + err(1, "%s", out.name); + } + + getfdtype(&out); + + if (caph_rights_limit(out.fd, &rights) == -1) + err(1, "unable to limit capability rights"); + if (caph_ioctls_limit(out.fd, cmds, nitems(cmds)) == -1) + err(1, "unable to limit capability rights"); + + if (in.fd != STDIN_FILENO && out.fd != STDIN_FILENO) { + if (caph_limit_stdin() == -1) + err(1, "unable to limit capability rights"); + } + + if (in.fd != STDOUT_FILENO && out.fd != STDOUT_FILENO) { + if (caph_limit_stdout() == -1) + err(1, "unable to limit capability rights"); + } + + if (in.fd != STDERR_FILENO && out.fd != STDERR_FILENO) { + if (caph_limit_stderr() == -1) + err(1, "unable to limit capability rights"); + } + + /* + * Allocate space for the input and output buffers. If not doing + * record oriented I/O, only need a single buffer. + */ + if (!(ddflags & (C_BLOCK | C_UNBLOCK))) { + if ((in.db = malloc((size_t)out.dbsz + in.dbsz - 1)) == NULL) + err(1, "input buffer"); + out.db = in.db; + } else if ((in.db = malloc(MAX((size_t)in.dbsz, cbsz) + cbsz)) == NULL || + (out.db = malloc(out.dbsz + cbsz)) == NULL) + err(1, "output buffer"); + + /* dbp is the first free position in each buffer. */ + in.dbp = in.db; + out.dbp = out.db; + + /* Position the input/output streams. */ + if (in.offset) + pos_in(); + if (out.offset) + pos_out(); + + /* + * Truncate the output file. If it fails on a type of output file + * that it should _not_ fail on, error out. + */ + if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK) && + out.flags & ISTRUNC) + if (ftruncate(out.fd, out.offset * out.dbsz) == -1) + err(1, "truncating %s", out.name); + + if (ddflags & (C_LCASE | C_UCASE | C_ASCII | C_EBCDIC | C_PARITY)) { + if (ctab != NULL) { + for (cnt = 0; cnt <= 0377; ++cnt) + casetab[cnt] = ctab[cnt]; + } else { + for (cnt = 0; cnt <= 0377; ++cnt) + casetab[cnt] = cnt; + } + if ((ddflags & C_PARITY) && !(ddflags & C_ASCII)) { + /* + * If the input is not EBCDIC, and we do parity + * processing, strip input parity. + */ + for (cnt = 200; cnt <= 0377; ++cnt) + casetab[cnt] = casetab[cnt & 0x7f]; + } + if (ddflags & C_LCASE) { + for (cnt = 0; cnt <= 0377; ++cnt) + casetab[cnt] = tolower(casetab[cnt]); + } else if (ddflags & C_UCASE) { + for (cnt = 0; cnt <= 0377; ++cnt) + casetab[cnt] = toupper(casetab[cnt]); + } + if ((ddflags & C_PARITY)) { + /* + * This should strictly speaking be a no-op, but I + * wonder what funny LANG settings could get us. + */ + for (cnt = 0; cnt <= 0377; ++cnt) + casetab[cnt] = casetab[cnt] & 0x7f; + } + if ((ddflags & C_PARSET)) { + for (cnt = 0; cnt <= 0377; ++cnt) + casetab[cnt] = casetab[cnt] | 0x80; + } + if ((ddflags & C_PAREVEN)) { + for (cnt = 0; cnt <= 0377; ++cnt) + if (parity(casetab[cnt])) + casetab[cnt] = casetab[cnt] | 0x80; + } + if ((ddflags & C_PARODD)) { + for (cnt = 0; cnt <= 0377; ++cnt) + if (!parity(casetab[cnt])) + casetab[cnt] = casetab[cnt] | 0x80; + } + + ctab = casetab; + } + + if (clock_gettime(CLOCK_MONOTONIC, &st.start)) + err(1, "clock_gettime"); +} + +static void +getfdtype(IO *io) +{ + struct stat sb; + int type; + + if (fstat(io->fd, &sb) == -1) + err(1, "%s", io->name); + if (S_ISREG(sb.st_mode)) + io->flags |= ISTRUNC; + if (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode)) { + if (ioctl(io->fd, FIODTYPE, &type) == -1) { + err(1, "%s", io->name); + } else { + if (type & D_TAPE) + io->flags |= ISTAPE; + else if (type & (D_DISK | D_MEM)) + io->flags |= ISSEEK; + if (S_ISCHR(sb.st_mode) && (type & D_TAPE) == 0) + io->flags |= ISCHR; + } + return; + } + errno = 0; + if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) + io->flags |= ISPIPE; + else + io->flags |= ISSEEK; +} + +/* + * Limit the speed by adding a delay before every block read. + * The delay (t_usleep) is equal to the time computed from block + * size and the specified speed limit (t_target) minus the time + * spent on actual read and write operations (t_io). + */ +static void +speed_limit(void) +{ + static double t_prev, t_usleep; + double t_now, t_io, t_target; + + t_now = secs_elapsed(); + t_io = t_now - t_prev - t_usleep; + t_target = (double)in.dbsz / (double)speed; + t_usleep = t_target - t_io; + if (t_usleep > 0) + usleep(t_usleep * 1000000); + else + t_usleep = 0; + t_prev = t_now; +} + +static void +swapbytes(void *v, size_t len) +{ + unsigned char *p = v; + unsigned char t; + + while (len > 1) { + t = p[0]; + p[0] = p[1]; + p[1] = t; + p += 2; + len -= 2; + } +} + +static void +dd_in(void) +{ + ssize_t n; + + for (;;) { + switch (cpy_cnt) { + case -1: /* count=0 was specified */ + return; + case 0: + break; + default: + if (st.in_full + st.in_part >= (uintmax_t)cpy_cnt) + return; + break; + } + + if (speed > 0) + speed_limit(); + + /* + * Zero the buffer first if sync; if doing block operations, + * use spaces. + */ + if (ddflags & C_SYNC) { + if (ddflags & C_FILL) + memset(in.dbp, fill_char, in.dbsz); + else if (ddflags & (C_BLOCK | C_UNBLOCK)) + memset(in.dbp, ' ', in.dbsz); + else + memset(in.dbp, 0, in.dbsz); + } + + in.dbrcnt = 0; +fill: + n = read(in.fd, in.dbp + in.dbrcnt, in.dbsz - in.dbrcnt); + + /* EOF */ + if (n == 0 && in.dbrcnt == 0) + return; + + /* Read error */ + if (n == -1) { + /* + * If noerror not specified, die. POSIX requires that + * the warning message be followed by an I/O display. + */ + if (!(ddflags & C_NOERROR)) + err(1, "%s", in.name); + warn("%s", in.name); + summary(); + + /* + * If it's a seekable file descriptor, seek past the + * error. If your OS doesn't do the right thing for + * raw disks this section should be modified to re-read + * in sector size chunks. + */ + if (in.flags & ISSEEK && + lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) + warn("%s", in.name); + + /* If sync not specified, omit block and continue. */ + if (!(ddflags & C_SYNC)) + continue; + } + + /* If conv=sync, use the entire block. */ + if (ddflags & C_SYNC) + n = in.dbsz; + + /* Count the bytes read for this block. */ + in.dbrcnt += n; + + /* Count the number of full and partial blocks. */ + if (in.dbrcnt == in.dbsz) + ++st.in_full; + else if (ddflags & C_IFULLBLOCK && n != 0) + goto fill; /* these don't count */ + else + ++st.in_part; + + /* Count the total bytes read for this file. */ + in.dbcnt += in.dbrcnt; + + /* + * POSIX states that if bs is set and no other conversions + * than noerror, notrunc or sync are specified, the block + * is output without buffering as it is read. + */ + if ((ddflags & ~(C_NOERROR | C_NOTRUNC | C_SYNC)) == C_BS) { + out.dbcnt = in.dbcnt; + dd_out(1); + in.dbcnt = 0; + continue; + } + + if (ddflags & C_SWAB) { + if ((n = in.dbrcnt) & 1) { + ++st.swab; + --n; + } + swapbytes(in.dbp, (size_t)n); + } + + /* Advance to the next block. */ + in.dbp += in.dbrcnt; + (*cfunc)(); + if (need_summary) + summary(); + if (need_progress) + progress(); + } +} + +/* + * Clean up any remaining I/O and flush output. If necessary, the output file + * is truncated. + */ +static void +dd_close(void) +{ + if (cfunc == def) + def_close(); + else if (cfunc == block) + block_close(); + else if (cfunc == unblock) + unblock_close(); + if (ddflags & C_OSYNC && out.dbcnt && out.dbcnt < out.dbsz) { + if (ddflags & C_FILL) + memset(out.dbp, fill_char, out.dbsz - out.dbcnt); + else if (ddflags & (C_BLOCK | C_UNBLOCK)) + memset(out.dbp, ' ', out.dbsz - out.dbcnt); + else + memset(out.dbp, 0, out.dbsz - out.dbcnt); + out.dbcnt = out.dbsz; + } + if (out.dbcnt || pending) + dd_out(1); + + /* + * If the file ends with a hole, ftruncate it to extend its size + * up to the end of the hole (without having to write any data). + */ + if (out.seek_offset > 0 && (out.flags & ISTRUNC)) { + if (ftruncate(out.fd, out.seek_offset) == -1) + err(1, "truncating %s", out.name); + } + + if (ddflags & C_FSYNC) { + if (fsync(out.fd) == -1) + err(1, "fsyncing %s", out.name); + } else if (ddflags & C_FDATASYNC) { + if (fdatasync(out.fd) == -1) + err(1, "fdatasyncing %s", out.name); + } +} + +void +dd_out(int force) +{ + u_char *outp; + size_t cnt, n; + ssize_t nw; + static int warned; + int sparse; + + /* + * Write one or more blocks out. The common case is writing a full + * output block in a single write; increment the full block stats. + * Otherwise, we're into partial block writes. If a partial write, + * and it's a character device, just warn. If a tape device, quit. + * + * The partial writes represent two cases. 1: Where the input block + * was less than expected so the output block was less than expected. + * 2: Where the input block was the right size but we were forced to + * write the block in multiple chunks. The original versions of dd(1) + * never wrote a block in more than a single write, so the latter case + * never happened. + * + * One special case is if we're forced to do the write -- in that case + * we play games with the buffer size, and it's usually a partial write. + */ + outp = out.db; + + /* + * If force, first try to write all pending data, else try to write + * just one block. Subsequently always write data one full block at + * a time at most. + */ + for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { + cnt = n; + do { + sparse = 0; + if (ddflags & C_SPARSE) { + /* Is buffer sparse? */ + sparse = BISZERO(outp, cnt); + } + if (sparse && !force) { + pending += cnt; + nw = cnt; + } else { + if (pending != 0) { + /* + * Seek past hole. Note that we need to record the + * reached offset, because we might have no more data + * to write, in which case we'll need to call + * ftruncate to extend the file size. + */ + out.seek_offset = lseek(out.fd, pending, SEEK_CUR); + if (out.seek_offset == -1) + err(2, "%s: seek error creating sparse file", + out.name); + pending = 0; + } + if (cnt) { + nw = write(out.fd, outp, cnt); + out.seek_offset = 0; + } else { + return; + } + } + + if (nw <= 0) { + if (nw == 0) + errx(1, "%s: end of device", out.name); + if (errno != EINTR) + err(1, "%s", out.name); + nw = 0; + } + + outp += nw; + st.bytes += nw; + + if ((size_t)nw == n && n == (size_t)out.dbsz) + ++st.out_full; + else + ++st.out_part; + + if ((size_t) nw != cnt) { + if (out.flags & ISTAPE) + errx(1, "%s: short write on tape device", + out.name); + if (out.flags & ISCHR && !warned) { + warned = 1; + warnx("%s: short write on character device", + out.name); + } + } + + cnt -= nw; + } while (cnt != 0); + + if ((out.dbcnt -= n) < out.dbsz) + break; + } + + /* Reassemble the output block. */ + if (out.dbcnt) + (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); + out.dbp = out.db + out.dbcnt; +} |