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 #if 0
  41 #ifndef lint
  42 static char sccsid[] = "@(#)chpass.c    8.4 (Berkeley) 4/2/94";
  43 #endif /* not lint */
  44 #endif
  45
  46 #include <sys/cdefs.h>
  47 __FBSDID("$FreeBSD$");
  48
  49 #include <sys/param.h>
  50 #include <sys/stat.h>
  51 #include <sys/signal.h>
  52 #include <sys/time.h>
  53 #include <sys/resource.h>
  54
  55 #include <ctype.h>
  56 #include <err.h>
  57 #include <errno.h>
  58 #include <fcntl.h>
  59 #include <pwd.h>
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62 #include <string.h>
  63 #include <unistd.h>
  64
  65 #include <pw_scan.h>
  66 #include <pw_util.h>
  67 #include "pw_copy.h"
  68 #ifdef YP
  69 #include <rpcsvc/yp.h>
  70 int yp_errno = YP_TRUE;
  71 #include "pw_yp.h"
  72 #endif
  73
  74 #include "chpass.h"
  75 #include "pathnames.h"
  76
  77 char *tempname;
  78 uid_t uid;
  79
  80 void    baduser(void);
  81 void    usage(void);
  82
  83 char localhost[] = "localhost";
  84
  85 int
  86 main(int argc, char *argv[])
  87 {
  88         enum { NEWSH, LOADENTRY, EDITENTRY, NEWPW, NEWEXP } op;
  89         struct passwd *pw = NULL, lpw, old_pw;
  90         char *username = NULL;
  91         int ch, pfd, tfd;
  92         char *arg = NULL;
  93 #ifdef YP
  94         int force_local = 0;
  95         int force_yp = 0;
  96 #endif
  97
  98         op = EDITENTRY;
  99 #ifdef YP
 100         while ((ch = getopt(argc, argv, "a:p:s:e:d:h:oly")) != -1)
 101 #else
 102         while ((ch = getopt(argc, argv, "a:p:s:e:")) != -1)
 103 #endif
 104                 switch(ch) {
 105                 case 'a':
 106                         op = LOADENTRY;
 107                         arg = optarg;
 108                         break;
 109                 case 's':
 110                         op = NEWSH;
 111                         arg = optarg;
 112                         break;
 113                 case 'p':
 114                         op = NEWPW;
 115                         arg = optarg;
 116                         break;
 117                 case 'e':
 118                         op = NEWEXP;
 119                         arg = optarg;
 120                         break;
 121 #ifdef YP
 122                 case 'h':
 123 #ifdef PARANOID
 124                         if (getuid()) {
 125                                 warnx("Only the superuser can use the -h flag");
 126                         } else {
 127 #endif
 128                                 yp_server = optarg;
 129 #ifdef PARANOID
 130                         }
 131 #endif
 132                         break;
 133                 case 'd':
 134 #ifdef PARANOID
 135                         if (getuid()) {
 136                                 warnx("Only the superuser can use the -d flag");
 137                         } else {
 138 #endif
 139                                 yp_domain = optarg;
 140                                 if (yp_server == NULL)
 141                                         yp_server = localhost;
 142 #ifdef PARANOID
 143                         }
 144 #endif
 145                         break;
 146                 case 'l':
 147                         _use_yp = 0;
 148                         force_local = 1;
 149                         break;
 150                 case 'y':
 151                         _use_yp = force_yp = 1;
 152                         break;
 153                 case 'o':
 154                         force_old++;
 155                         break;
 156 #endif
 157                 case '?':
 158                 default:
 159                         usage();
 160                 }
 161         argc -= optind;
 162         argv += optind;
 163
 164         uid = getuid();
 165
 166         if (op == EDITENTRY || op == NEWSH || op == NEWPW || op == NEWEXP) {
 167                 switch(argc) {
 168 #ifdef YP
 169                 case 0:
 170                         GETPWUID(uid)
 171                         get_yp_master(1); /* XXX just to set the suser flag */
 172                         break;
 173                 case 1:
 174                         GETPWNAM(*argv)
 175                         get_yp_master(1); /* XXX just to set the suser flag */
 176 #else
 177                 case 0:
 178                         if (!(pw = getpwuid(uid)))
 179                                 errx(1, "unknown user: uid %lu",
 180                                     (unsigned long)uid);
 181                         break;
 182                 case 1:
 183                         if (!(pw = getpwnam(*argv)))
 184                                 errx(1, "unknown user: %s", *argv);
 185 #endif
 186                         if (uid && uid != pw->pw_uid)
 187                                 baduser();
 188                         break;
 189                 default:
 190                         usage();
 191                 }
 192
 193                 /* Make a copy for later verification */
 194                 old_pw = *pw;
 195                 old_pw.pw_gecos = strdup(old_pw.pw_gecos);
 196         }
 197
 198         if (op == NEWSH) {
 199                 /* protect p_shell -- it thinks NULL is /bin/sh */
 200                 if (!arg[0])
 201                         usage();
 202                 if (p_shell(arg, pw, (ENTRY *)NULL))
 203                         pw_error((char *)NULL, 0, 1);
 204         }
 205
 206         if (op == NEWEXP) {
 207                 if (uid)        /* only root can change expire */
 208                         baduser();
 209                 if (p_expire(arg, pw, (ENTRY *)NULL))
 210                         pw_error((char *)NULL, 0, 1);
 211         }
 212
 213         if (op == LOADENTRY) {
 214                 if (uid)
 215                         baduser();
 216                 pw = &lpw;
 217                 if (!__pw_scan(arg, pw, _PWSCAN_WARN|_PWSCAN_MASTER))
 218                         exit(1);
 219         }
 220         username = pw->pw_name;
 221
 222         if (op == NEWPW) {
 223                 if (uid)
 224                         baduser();
 225
 226                 if(strchr(arg, ':')) {
 227                         errx(1, "invalid format for password");
 228                 }
 229                 pw->pw_passwd = arg;
 230         }
 231
 232         /*
 233          * The temporary file/file descriptor usage is a little tricky here.
 234          * 1:   Create a temporary file called tempname, get descriptor tfd.
 235          * 2:   Display() gets an fp for the temporary file, and copies the
 236          *      user's information into it.  It then gives the temporary file
 237          *      to the user and closes the fp, closing the underlying fd.
 238          * 3:   The user edits the temporary file some number of times.
 239          *      The results are stored in pw by edit().
 240          * 4:   Delete the temporary file.
 241          * 5:   Make a new temporary file, descriptor tfd.
 242          * 6:   Get a descriptor for the master.passwd file, pfd, and
 243          *      lock master.passwd.
 244          * 7:   Pw_copy() gets descriptors for master.passwd and the
 245          *      temporary file and copies the master password file into it,
 246          *      replacing the modified user's record with a new one.  We can't
 247          *      use the first temporary file for this because it was owned
 248          *      by the user.  Pass the new and old user info.  Check the
 249          *      entry for our user has not been changed by someone else by
 250          *      while the user was editing by comparing the old info to
 251          *      the entry freshly read from master.passwd. Pw_copy() closes
 252          *      its fp, flushing the data and closing the underlying file
 253          *      descriptor.  We can't close the master password fp, or we'd
 254          *      lose the lock.
 255          * 8:   Call pw_mkdb() (which renames the temporary file) and exit.
 256          *      The exit closes the master passwd fp/fd.
 257          */
 258         pw_init();
 259         tfd = pw_tmp();
 260
 261         if (op == EDITENTRY) {
 262                 display(tfd, pw);
 263                 edit(pw);
 264                 (void)unlink(tempname);
 265                 tfd = pw_tmp();
 266         }
 267
 268 #ifdef YP
 269         if (_use_yp) {
 270                 yp_submit(pw);
 271                 (void)unlink(tempname);
 272         } else {
 273 #endif /* YP */
 274         pfd = pw_lock();
 275         pw_copy(pfd, tfd, pw, (op == LOADENTRY) ? NULL : &old_pw);
 276
 277         if (!pw_mkdb(username))
 278                 pw_error((char *)NULL, 0, 1);
 279 #ifdef YP
 280         }
 281 #endif /* YP */
 282         exit(0);
 283 }
 284
 285 void
 286 baduser(void)
 287 {
 288         errx(1, "%s", strerror(EACCES));
 289 }
 290
 291 void
 292 usage(void)
 293 {
 294
 295         (void)fprintf(stderr,
 296 #ifdef YP
 297                 "usage: chpass [-o] [-l] [-y] [-d domain] [-h host] [-a list] [-p encpass] [-s shell] [-e mmm dd yy] [user]\n");
 298 #else
 299                 "usage: chpass [-a list] [-p encpass] [-s shell] [-e mmm dd yy] [user]\n");
 300 #endif
 301         exit(1);
 302 }