chpass/chpass.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. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifndef lint
  35 static const char copyright[] =
  36 "@(#) Copyright (c) 1988, 1993, 1994\n\
  37         The Regents of the University of California.  All rights reserved.\n";
  38 #endif /* not lint */
  39
  40 #ifndef lint
  41 static const char sccsid[] = "From: @(#)chpass.c        8.4 (Berkeley) 4/2/94";
  42 static const char rcsid[] =
  43   "$FreeBSD$";
  44 #endif /* not lint */
  45
  46 #include <sys/param.h>
  47 #include <sys/stat.h>
  48 #include <sys/signal.h>
  49 #include <sys/time.h>
  50 #include <sys/resource.h>
  51
  52 #include <ctype.h>
  53 #include <err.h>
  54 #include <errno.h>
  55 #include <fcntl.h>
  56 #include <pwd.h>
  57 #include <stdio.h>
  58 #include <stdlib.h>
  59 #include <string.h>
  60 #include <unistd.h>
  61
  62 #include <pw_scan.h>
  63 #include <pw_util.h>
  64 #include "pw_copy.h"
  65 #ifdef YP
  66 #include <rpcsvc/yp.h>
  67 int yp_errno = YP_TRUE;
  68 #include "pw_yp.h"
  69 #endif
  70
  71 #include "chpass.h"
  72 #include "pathnames.h"
  73
  74 char *tempname;
  75 uid_t uid;
  76
  77 void    baduser(void);
  78 void    usage(void);
  79
  80 int
  81 main(argc, argv)
  82         int argc;
  83         char **argv;
  84 {
  85         enum { NEWSH, LOADENTRY, EDITENTRY, NEWPW, NEWEXP } op;
  86         struct passwd *pw = NULL, lpw, old_pw;
  87         char *username = NULL;
  88         int ch, pfd, tfd;
  89         char *arg = NULL;
  90 #ifdef YP
  91         int force_local = 0;
  92         int force_yp = 0;
  93 #endif
  94
  95         op = EDITENTRY;
  96 #ifdef YP
  97         while ((ch = getopt(argc, argv, "a:p:s:e:d:h:oly")) != -1)
  98 #else
  99         while ((ch = getopt(argc, argv, "a:p:s:e:")) != -1)
 100 #endif
 101                 switch(ch) {
 102                 case 'a':
 103                         op = LOADENTRY;
 104                         arg = optarg;
 105                         break;
 106                 case 's':
 107                         op = NEWSH;
 108                         arg = optarg;
 109                         break;
 110                 case 'p':
 111                         op = NEWPW;
 112                         arg = optarg;
 113                         break;
 114                 case 'e':
 115                         op = NEWEXP;
 116                         arg = optarg;
 117                         break;
 118 #ifdef YP
 119                 case 'h':
 120 #ifdef PARANOID
 121                         if (getuid()) {
 122                                 warnx("Only the superuser can use the -h flag");
 123                         } else {
 124 #endif
 125                                 yp_server = optarg;
 126 #ifdef PARANOID
 127                         }
 128 #endif
 129                         break;
 130                 case 'd':
 131 #ifdef PARANOID
 132                         if (getuid()) {
 133                                 warnx("Only the superuser can use the -d flag");
 134                         } else {
 135 #endif
 136                                 yp_domain = optarg;
 137                                 if (yp_server == NULL)
 138                                         yp_server = "localhost";
 139 #ifdef PARANOID
 140                         }
 141 #endif
 142                         break;
 143                 case 'l':
 144                         _use_yp = 0;
 145                         force_local = 1;
 146                         break;
 147                 case 'y':
 148                         _use_yp = force_yp = 1;
 149                         break;
 150                 case 'o':
 151                         force_old++;
 152                         break;
 153 #endif
 154                 case '?':
 155                 default:
 156                         usage();
 157                 }
 158         argc -= optind;
 159         argv += optind;
 160
 161         uid = getuid();
 162
 163         if (op == EDITENTRY || op == NEWSH || op == NEWPW || op == NEWEXP) {
 164                 switch(argc) {
 165 #ifdef YP
 166                 case 0:
 167                         GETPWUID(uid)
 168                         get_yp_master(1); /* XXX just to set the suser flag */
 169                         break;
 170                 case 1:
 171                         GETPWNAM(*argv)
 172                         get_yp_master(1); /* XXX just to set the suser flag */
 173 #else
 174                 case 0:
 175                         if (!(pw = getpwuid(uid)))
 176                                 errx(1, "unknown user: uid %lu",
 177                                     (unsigned long)uid);
 178                         break;
 179                 case 1:
 180                         if (!(pw = getpwnam(*argv)))
 181                                 errx(1, "unknown user: %s", *argv);
 182 #endif
 183                         if (uid && uid != pw->pw_uid)
 184                                 baduser();
 185                         break;
 186                 default:
 187                         usage();
 188                 }
 189
 190                 /* Make a copy for later verification */
 191                 old_pw = *pw;
 192                 old_pw.pw_gecos = strdup(old_pw.pw_gecos);
 193         }
 194
 195         if (op == NEWSH) {
 196                 /* protect p_shell -- it thinks NULL is /bin/sh */
 197                 if (!arg[0])
 198                         usage();
 199                 if (p_shell(arg, pw, (ENTRY *)NULL))
 200                         pw_error((char *)NULL, 0, 1);
 201         }
 202
 203         if (op == NEWEXP) {
 204                 if (uid)        /* only root can change expire */
 205                         baduser();
 206                 if (p_expire(arg, pw, (ENTRY *)NULL))
 207                         pw_error((char *)NULL, 0, 1);
 208         }
 209
 210         if (op == LOADENTRY) {
 211                 if (uid)
 212                         baduser();
 213                 pw = &lpw;
 214                 if (!__pw_scan(arg, pw, _PWSCAN_WARN|_PWSCAN_MASTER))
 215                         exit(1);
 216         }
 217         username = pw->pw_name;
 218
 219         if (op == NEWPW) {
 220                 if (uid)
 221                         baduser();
 222
 223                 if(strchr(arg, ':')) {
 224                         errx(1, "invalid format for password");
 225                 }
 226                 pw->pw_passwd = arg;
 227         }
 228
 229         /*
 230          * The temporary file/file descriptor usage is a little tricky here.
 231          * 1:   Create a temporary file called tempname, get descriptor tfd.
 232          * 2:   Display() gets an fp for the temporary file, and copies the
 233          *      user's information into it.  It then gives the temporary file
 234          *      to the user and closes the fp, closing the underlying fd.
 235          * 3:   The user edits the temporary file some number of times.
 236          *      The results are stored in pw by edit().
 237          * 4:   Delete the temporary file.
 238          * 5:   Make a new temporary file, descriptor tfd.
 239          * 6:   Get a descriptor for the master.passwd file, pfd, and
 240          *      lock master.passwd.
 241          * 7:   Pw_copy() gets descriptors for master.passwd and the
 242          *      temporary file and copies the master password file into it,
 243          *      replacing the modified user's record with a new one.  We can't
 244          *      use the first temporary file for this because it was owned
 245          *      by the user.  Pass the new and old user info.  Check the
 246          *      entry for our user has not been changed by someone else by
 247          *      while the user was editing by comparing the old info to
 248          *      the entry freshly read from master.passwd. Pw_copy() closes
 249          *      its fp, flushing the data and closing the underlying file
 250          *      descriptor.  We can't close the master password fp, or we'd
 251          *      lose the lock.
 252          * 8:   Call pw_mkdb() (which renames the temporary file) and exit.
 253          *      The exit closes the master passwd fp/fd.
 254          */
 255         pw_init();
 256         tfd = pw_tmp();
 257
 258         if (op == EDITENTRY) {
 259                 display(tfd, pw);
 260                 edit(pw);
 261                 (void)unlink(tempname);
 262                 tfd = pw_tmp();
 263         }
 264
 265 #ifdef YP
 266         if (_use_yp) {
 267                 yp_submit(pw);
 268                 (void)unlink(tempname);
 269         } else {
 270 #endif /* YP */
 271         pfd = pw_lock();
 272         pw_copy(pfd, tfd, pw, (op == LOADENTRY) ? NULL : &old_pw);
 273
 274         if (!pw_mkdb(username))
 275                 pw_error((char *)NULL, 0, 1);
 276 #ifdef YP
 277         }
 278 #endif /* YP */
 279         exit(0);
 280 }
 281
 282 void
 283 baduser()
 284 {
 285         errx(1, "%s", strerror(EACCES));
 286 }
 287
 288 void
 289 usage()
 290 {
 291
 292         (void)fprintf(stderr,
 293 #ifdef YP
 294                 "usage: chpass [-l] [-y] [-d domain [-h host]] [-a list] [-p encpass] [-s shell] [-e mmm dd yy] [user]\n");
 295 #else
 296                 "usage: chpass [-a list] [-p encpass] [-s shell] [-e mmm dd yy] [user]\n");
 297 #endif
 298         exit(1);
 299 }