bin/cp/utils.c

   1 /* $NetBSD: utils.c,v 1.33 2007/10/25 03:51:14 jld Exp $ */
   2
   3 /*-
   4  * Copyright (c) 1991, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)utils.c     8.3 (Berkeley) 4/1/94";
  36 #else
  37 __RCSID("$NetBSD: utils.c,v 1.33 2007/10/25 03:51:14 jld Exp $");
  38 #endif
  39 #endif /* not lint */
  40
  41 #include <sys/mman.h>
  42 #include <sys/param.h>
  43 #include <sys/stat.h>
  44 #include <sys/time.h>
  45
  46 #include <err.h>
  47 #include <errno.h>
  48 #include <fcntl.h>
  49 #include <fts.h>
  50 #include <stdio.h>
  51 #include <stdlib.h>
  52 #include <string.h>
  53 #include <unistd.h>
  54
  55 #include "extern.h"
  56
  57 int
  58 set_utimes(const char *file, struct stat *fs)
  59 {
  60     static struct timeval tv[2];
  61
  62     TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
  63     TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
  64
  65     if (lutimes(file, tv)) {
  66         warn("lutimes: %s", file);
  67         return (1);
  68     }
  69     return (0);
  70 }
  71
  72 int
  73 copy_file(FTSENT *entp, int dne)
  74 {
  75         static char buf[MAXBSIZE];
  76         struct stat to_stat, *fs;
  77         int ch, checkch, from_fd, rcount, rval, to_fd, tolnk, wcount;
  78         char *p;
  79
  80         if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
  81                 warn("%s", entp->fts_path);
  82                 return (1);
  83         }
  84
  85         to_fd = -1;
  86         fs = entp->fts_statp;
  87         tolnk = ((Rflag && !(Lflag || Hflag)) || Pflag);
  88
  89         /*
  90          * If the file exists and we're interactive, verify with the user.
  91          * If the file DNE, set the mode to be the from file, minus setuid
  92          * bits, modified by the umask; arguably wrong, but it makes copying
  93          * executables work right and it's been that way forever.  (The
  94          * other choice is 666 or'ed with the execute bits on the from file
  95          * modified by the umask.)
  96          */
  97         if (!dne) {
  98                 struct stat sb;
  99                 int sval;
 100
 101                 if (iflag) {
 102                         (void)fprintf(stderr, "overwrite %s? ", to.p_path);
 103                         checkch = ch = getchar();
 104                         while (ch != '\n' && ch != EOF)
 105                                 ch = getchar();
 106                         if (checkch != 'y' && checkch != 'Y') {
 107                                 (void)close(from_fd);
 108                                 return (0);
 109                         }
 110                 }
 111
 112                 sval = tolnk ?
 113                         lstat(to.p_path, &sb) : stat(to.p_path, &sb);
 114                 if (sval == -1) {
 115                         warn("stat: %s", to.p_path);
 116                         return (1);
 117                 }
 118
 119                 if (!(tolnk && S_ISLNK(sb.st_mode)))
 120                         to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
 121         } else
 122                 to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
 123                     fs->st_mode & ~(S_ISUID | S_ISGID));
 124
 125         if (to_fd == -1 && (fflag || tolnk)) {
 126                 /*
 127                  * attempt to remove existing destination file name and
 128                  * create a new file
 129                  */
 130                 (void)unlink(to.p_path);
 131                 to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
 132                              fs->st_mode & ~(S_ISUID | S_ISGID));
 133         }
 134
 135         if (to_fd == -1) {
 136                 warn("%s", to.p_path);
 137                 (void)close(from_fd);
 138                 return (1);
 139         }
 140
 141         rval = 0;
 142
 143         /*
 144          * There's no reason to do anything other than close the file
 145          * now if it's empty, so let's not bother.
 146          */
 147
 148         if (fs->st_size > 0) {
 149
 150                 /*
 151                  * Mmap and write if less than 8M (the limit is so
 152                  * we don't totally trash memory on big files).
 153                  * This is really a minor hack, but it wins some CPU back.
 154                  */
 155
 156                 if (fs->st_size <= 8 * 1048576) {
 157                         size_t fsize = (size_t)fs->st_size;
 158                         p = mmap(NULL, fsize, PROT_READ, MAP_FILE|MAP_SHARED,
 159                             from_fd, (off_t)0);
 160                         if (p == MAP_FAILED) {
 161                                 goto mmap_failed;
 162                         } else {
 163                                 (void) madvise(p, (size_t)fs->st_size,
 164                                      MADV_SEQUENTIAL);
 165                                 if (write(to_fd, p, fsize) !=
 166                                     fs->st_size) {
 167                                         warn("%s", to.p_path);
 168                                         rval = 1;
 169                                 }
 170                                 if (munmap(p, fsize) < 0) {
 171                                         warn("%s", entp->fts_path);
 172                                         rval = 1;
 173                                 }
 174                         }
 175                 } else {
 176 mmap_failed:
 177                         while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
 178                                 wcount = write(to_fd, buf, (size_t)rcount);
 179                                 if (rcount != wcount || wcount == -1) {
 180                                         warn("%s", to.p_path);
 181                                         rval = 1;
 182                                         break;
 183                                 }
 184                         }
 185                         if (rcount < 0) {
 186                                 warn("%s", entp->fts_path);
 187                                 rval = 1;
 188                         }
 189                 }
 190         }
 191
 192         if (rval == 1) {
 193                 (void)close(from_fd);
 194                 (void)close(to_fd);
 195                 return (1);
 196         }
 197
 198         if (pflag && setfile(fs, to_fd))
 199                 rval = 1;
 200         /*
 201          * If the source was setuid or setgid, lose the bits unless the
 202          * copy is owned by the same user and group.
 203          */
 204 #define RETAINBITS \
 205         (S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
 206         if (!pflag && dne
 207             && fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid) {
 208                 if (fstat(to_fd, &to_stat)) {
 209                         warn("%s", to.p_path);
 210                         rval = 1;
 211                 } else if (fs->st_gid == to_stat.st_gid &&
 212                     fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) {
 213                         warn("%s", to.p_path);
 214                         rval = 1;
 215                 }
 216         }
 217         (void)close(from_fd);
 218         if (close(to_fd)) {
 219                 warn("%s", to.p_path);
 220                 rval = 1;
 221         }
 222         /* set the mod/access times now after close of the fd */
 223         if (pflag && set_utimes(to.p_path, fs)) {
 224             rval = 1;
 225         }
 226         return (rval);
 227 }
 228
 229 int
 230 copy_link(FTSENT *p, int exists)
 231 {
 232         int len;
 233         char target[MAXPATHLEN];
 234
 235         if ((len = readlink(p->fts_path, target, sizeof(target)-1)) == -1) {
 236                 warn("readlink: %s", p->fts_path);
 237                 return (1);
 238         }
 239         target[len] = '\0';
 240         if (exists && unlink(to.p_path)) {
 241                 warn("unlink: %s", to.p_path);
 242                 return (1);
 243         }
 244         if (symlink(target, to.p_path)) {
 245                 warn("symlink: %s", target);
 246                 return (1);
 247         }
 248         return (pflag ? setfile(p->fts_statp, 0) : 0);
 249 }
 250
 251 int
 252 copy_fifo(struct stat *from_stat, int exists)
 253 {
 254         if (exists && unlink(to.p_path)) {
 255                 warn("unlink: %s", to.p_path);
 256                 return (1);
 257         }
 258         if (mkfifo(to.p_path, from_stat->st_mode)) {
 259                 warn("mkfifo: %s", to.p_path);
 260                 return (1);
 261         }
 262         return (pflag ? setfile(from_stat, 0) : 0);
 263 }
 264
 265 int
 266 copy_special(struct stat *from_stat, int exists)
 267 {
 268         if (exists && unlink(to.p_path)) {
 269                 warn("unlink: %s", to.p_path);
 270                 return (1);
 271         }
 272         if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
 273                 warn("mknod: %s", to.p_path);
 274                 return (1);
 275         }
 276         return (pflag ? setfile(from_stat, 0) : 0);
 277 }
 278
 279
 280 /*
 281  * Function: setfile
 282  *
 283  * Purpose:
 284  *   Set the owner/group/permissions for the "to" file to the information
 285  *   in the stat structure.  If fd is zero, also call set_utimes() to set
 286  *   the mod/access times.  If fd is non-zero, the caller must do a utimes
 287  *   itself after close(fd).
 288  */
 289 int
 290 setfile(struct stat *fs, int fd)
 291 {
 292         int rval, islink;
 293
 294         rval = 0;
 295         islink = S_ISLNK(fs->st_mode);
 296         fs->st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
 297
 298         /*
 299          * Changing the ownership probably won't succeed, unless we're root
 300          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 301          * the mode; current BSD behavior is to remove all setuid bits on
 302          * chown.  If chown fails, lose setuid/setgid bits.
 303          */
 304         if (fd ? fchown(fd, fs->st_uid, fs->st_gid) :
 305             lchown(to.p_path, fs->st_uid, fs->st_gid)) {
 306                 if (errno != EPERM) {
 307                         warn("chown: %s", to.p_path);
 308                         rval = 1;
 309                 }
 310                 fs->st_mode &= ~(S_ISUID | S_ISGID);
 311         }
 312         if (fd ? fchmod(fd, fs->st_mode) : lchmod(to.p_path, fs->st_mode)) {
 313                 warn("chmod: %s", to.p_path);
 314                 rval = 1;
 315         }
 316
 317         if (!islink && !Nflag) {
 318                 unsigned long fflags = fs->st_flags;
 319                 /*
 320                  * XXX
 321                  * NFS doesn't support chflags; ignore errors unless
 322                  * there's reason to believe we're losing bits.
 323                  * (Note, this still won't be right if the server
 324                  * supports flags and we were trying to *remove* flags
 325                  * on a file that we copied, i.e., that we didn't create.)
 326                  */
 327                 errno = 0;
 328                 if ((fd ? fchflags(fd, fflags) :
 329                     chflags(to.p_path, fflags)) == -1)
 330                         if (errno != EOPNOTSUPP || fs->st_flags != 0) {
 331                                 warn("chflags: %s", to.p_path);
 332                                 rval = 1;
 333                         }
 334         }
 335         /* if fd is non-zero, caller must call set_utimes() after close() */
 336         if (fd == 0 && set_utimes(to.p_path, fs))
 337             rval = 1;
 338         return (rval);
 339 }
 340
 341 void
 342 usage(void)
 343 {
 344         (void)fprintf(stderr,
 345             "usage: %s [-R [-H | -L | -P]] [-f | -i] [-Npv] src target\n"
 346             "       %s [-R [-H | -L | -P]] [-f | -i] [-Npv] src1 ... srcN directory\n",
 347             getprogname(), getprogname());
 348         exit(1);
 349         /* NOTREACHED */
 350 }