usr.sbin/chown/chown.c

   1 /*
   2  * Copyright (c) 1988, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#) Copyright (c) 1988, 1993, 1994 The Regents of the University of California.  All rights reserved.
  30  * @(#)chown.c  8.8 (Berkeley) 4/4/94
  31  * $FreeBSD: head/usr.sbin/chown/chown.c 282208 2015-04-29 00:49:00Z smh $
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/stat.h>
  36
  37 #include <err.h>
  38 #include <errno.h>
  39 #include <fcntl.h>
  40 #include <fts.h>
  41 #include <grp.h>
  42 #include <libgen.h>
  43 #include <pwd.h>
  44 #include <stdint.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <unistd.h>
  49
  50 static void     a_gid(const char *);
  51 static void     a_uid(const char *);
  52 static void     chownerr(const char *);
  53 static uid_t    id(const char *, const char *);
  54 static void     usage(void);
  55
  56 static uid_t     uid;
  57 static gid_t     gid;
  58 static int       ischown;
  59 static const char       *gname;
  60
  61 int
  62 main(int argc, char **argv)
  63 {
  64         FTS *ftsp;
  65         FTSENT *p;
  66         int Hflag, Lflag, Rflag, fflag, hflag, vflag, xflag;
  67         int ch, fts_options, rval;
  68         char *cp;
  69
  70         ischown = (strcmp(basename(argv[0]), "chown") == 0);
  71
  72         Hflag = Lflag = Rflag = fflag = hflag = vflag = xflag = 0;
  73         while ((ch = getopt(argc, argv, "HLPRfhvx")) != -1)
  74                 switch (ch) {
  75                 case 'H':
  76                         Hflag = 1;
  77                         Lflag = 0;
  78                         break;
  79                 case 'L':
  80                         Lflag = 1;
  81                         Hflag = 0;
  82                         break;
  83                 case 'P':
  84                         Hflag = Lflag = 0;
  85                         break;
  86                 case 'R':
  87                         Rflag = 1;
  88                         break;
  89                 case 'f':
  90                         fflag = 1;
  91                         break;
  92                 case 'h':
  93                         hflag = 1;
  94                         break;
  95                 case 'v':
  96                         vflag++;
  97                         break;
  98                 case 'x':
  99                         xflag = 1;
 100                         break;
 101                 default:
 102                         usage();
 103                 }
 104         argv += optind;
 105         argc -= optind;
 106
 107         if (argc < 2)
 108                 usage();
 109
 110         if (Rflag) {
 111                 if (hflag && (Hflag || Lflag))
 112                         errx(1, "the -R%c and -h options may not be "
 113                             "specified together", Hflag ? 'H' : 'L');
 114                 if (Lflag) {
 115                         fts_options = FTS_LOGICAL;
 116                 } else {
 117                         fts_options = FTS_PHYSICAL;
 118
 119                         if (Hflag) {
 120                                 fts_options |= FTS_COMFOLLOW;
 121                         }
 122                 }
 123         } else if (hflag) {
 124                 fts_options = FTS_PHYSICAL;
 125         } else {
 126                 fts_options = FTS_LOGICAL;
 127         }
 128
 129         if (xflag)
 130                 fts_options |= FTS_XDEV;
 131
 132         uid = (uid_t)-1;
 133         gid = (gid_t)-1;
 134         if (ischown) {
 135                 if ((cp = strchr(*argv, ':')) != NULL) {
 136                         *cp++ = '\0';
 137                         a_gid(cp);
 138                 }
 139 #ifdef SUPPORT_DOT
 140                 else if ((cp = strchr(*argv, '.')) != NULL) {
 141                         warnx("separation of user and group with a period is deprecated");
 142                         *cp++ = '\0';
 143                         a_gid(cp);
 144                 }
 145 #endif
 146                 a_uid(*argv);
 147         } else
 148                 a_gid(*argv);
 149
 150         if ((ftsp = fts_open(++argv, fts_options, 0)) == NULL)
 151                 err(1, NULL);
 152
 153         for (rval = 0; (p = fts_read(ftsp)) != NULL;) {
 154                 int atflag;
 155
 156                 if ((fts_options & FTS_LOGICAL) ||
 157                     ((fts_options & FTS_COMFOLLOW) &&
 158                     p->fts_level == FTS_ROOTLEVEL))
 159                         atflag = 0;
 160                 else
 161                         atflag = AT_SYMLINK_NOFOLLOW;
 162
 163                 switch (p->fts_info) {
 164                 case FTS_D:                     /* Change it at FTS_DP. */
 165                         if (!Rflag)
 166                                 fts_set(ftsp, p, FTS_SKIP);
 167                         continue;
 168                 case FTS_DNR:                   /* Warn, chown. */
 169                         warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
 170                         rval = 1;
 171                         break;
 172                 case FTS_ERR:                   /* Warn, continue. */
 173                 case FTS_NS:
 174                         warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
 175                         rval = 1;
 176                         continue;
 177                 default:
 178                         break;
 179                 }
 180                 if ((uid == (uid_t)(-1) || uid == p->fts_statp->st_uid) &&
 181                     (gid == (gid_t)(-1) || gid == p->fts_statp->st_gid))
 182                         continue;
 183                 if (fchownat(AT_FDCWD, p->fts_accpath, uid, gid, atflag)
 184                     == -1 && !fflag) {
 185                         chownerr(p->fts_path);
 186                         rval = 1;
 187                 } else if (vflag) {
 188                         printf("%s", p->fts_path);
 189                         if (vflag > 1) {
 190                                 if (ischown) {
 191                                         printf(": %ju:%ju -> %ju:%ju",
 192                                             (uintmax_t)
 193                                             p->fts_statp->st_uid,
 194                                             (uintmax_t)
 195                                             p->fts_statp->st_gid,
 196                                             (uid == (uid_t)(-1)) ?
 197                                             (uintmax_t)
 198                                             p->fts_statp->st_uid :
 199                                             (uintmax_t)uid,
 200                                             (gid == (gid_t)(-1)) ?
 201                                             (uintmax_t)
 202                                             p->fts_statp->st_gid :
 203                                             (uintmax_t)gid);
 204                                 } else {
 205                                         printf(": %ju -> %ju",
 206                                             (uintmax_t)
 207                                             p->fts_statp->st_gid,
 208                                             (gid == (gid_t)(-1)) ?
 209                                             (uintmax_t)
 210                                             p->fts_statp->st_gid :
 211                                             (uintmax_t)gid);
 212                                 }
 213                         }
 214                         printf("\n");
 215                 }
 216         }
 217         if (errno)
 218                 err(1, "fts_read");
 219         exit(rval);
 220 }
 221
 222 static void
 223 a_gid(const char *s)
 224 {
 225         struct group *gr;
 226
 227         if (*s == '\0')                 /* Argument was "uid[:.]". */
 228                 return;
 229         gname = s;
 230         gid = ((gr = getgrnam(s)) != NULL) ? gr->gr_gid : id(s, "group");
 231 }
 232
 233 static void
 234 a_uid(const char *s)
 235 {
 236         struct passwd *pw;
 237
 238         if (*s == '\0')                 /* Argument was "[:.]gid". */
 239                 return;
 240         uid = ((pw = getpwnam(s)) != NULL) ? pw->pw_uid : id(s, "user");
 241 }
 242
 243 static uid_t
 244 id(const char *name, const char *type)
 245 {
 246         uid_t val;
 247         char *ep;
 248
 249         /*
 250          * XXX
 251          * We know that uid_t's and gid_t's are unsigned longs.
 252          */
 253         errno = 0;
 254         val = strtoul(name, &ep, 10);
 255         if (errno || *ep != '\0')
 256                 errx(1, "%s: illegal %s name", name, type);
 257         return (val);
 258 }
 259
 260 static void
 261 chownerr(const char *file)
 262 {
 263         static uid_t euid = -1;
 264         static int ngroups = -1;
 265         static long ngroups_max;
 266         gid_t *groups;
 267
 268         /* Check for chown without being root. */
 269         if (errno != EPERM || (uid != (uid_t)(-1) &&
 270             euid == (uid_t)(-1) && (euid = geteuid()) != 0)) {
 271                 warn("%s", file);
 272                 return;
 273         }
 274
 275         /* Check group membership; kernel just returns EPERM. */
 276         if (gid != (gid_t)(-1) && ngroups == -1 &&
 277             euid == (uid_t)(-1) && (euid = geteuid()) != 0) {
 278                 ngroups_max = sysconf(_SC_NGROUPS_MAX) + 1;
 279                 if ((groups = malloc(sizeof(gid_t) * ngroups_max)) == NULL)
 280                         err(1, "malloc");
 281                 ngroups = getgroups(ngroups_max, groups);
 282                 while (--ngroups >= 0 && gid != groups[ngroups]);
 283                 free(groups);
 284                 if (ngroups < 0) {
 285                         warnx("you are not a member of group %s", gname);
 286                         return;
 287                 }
 288         }
 289         warn("%s", file);
 290 }
 291
 292 static void
 293 usage(void)
 294 {
 295
 296         if (ischown)
 297                 fprintf(stderr, "%s\n%s\n",
 298                     "usage: chown [-fhvx] [-R [-H | -L | -P]] owner[:group]"
 299                     " file ...",
 300                     "       chown [-fhvx] [-R [-H | -L | -P]] :group file ...");
 301         else
 302                 fprintf(stderr, "%s\n",
 303                     "usage: chgrp [-fhvx] [-R [-H | -L | -P]] group file ...");
 304         exit(1);
 305 }