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 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 char sccsid[] = "From: @(#)chpass.c      8.4 (Berkeley) 4/2/94";
  42 static char rcsid[] =
  43         "$Id: chpass.c,v 1.9 1996/07/01 19:38:07 guido Exp $";
  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 __P((void));
  78 void    usage __P((void));
  79
  80 int
  81 main(argc, argv)
  82         int argc;
  83         char **argv;
  84 {
  85         enum { NEWSH, LOADENTRY, EDITENTRY, NEWPW } op;
  86         struct passwd *pw, lpw;
  87         char *username = NULL;
  88         int ch, pfd, tfd;
  89         char *arg;
  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:d:h:oly")) != EOF)
  98 #else
  99         while ((ch = getopt(argc, argv, "a:p:s:")) != EOF)
 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 #ifdef YP
 115                 case 'h':
 116 #ifdef PARANOID
 117                         if (getuid()) {
 118                                 warnx("Only the superuser can use the -h flag");
 119                         } else {
 120 #endif
 121                                 yp_server = optarg;
 122 #ifdef PARANOID
 123                         }
 124 #endif
 125                         break;
 126                 case 'd':
 127 #ifdef PARANOID
 128                         if (getuid()) {
 129                                 warnx("Only the superuser can use the -d flag");
 130                         } else {
 131 #endif
 132                                 yp_domain = optarg;
 133                                 if (yp_server == NULL)
 134                                         yp_server = "localhost";
 135 #ifdef PARANOID
 136                         }
 137 #endif
 138                         break;
 139                 case 'l':
 140                         _use_yp = 0;
 141                         force_local = 1;
 142                         break;
 143                 case 'y':
 144                         _use_yp = force_yp = 1;
 145                         break;
 146                 case 'o':
 147                         force_old++;
 148                         break;
 149 #endif
 150                 case '?':
 151                 default:
 152                         usage();
 153                 }
 154         argc -= optind;
 155         argv += optind;
 156
 157         uid = getuid();
 158
 159         if (op == EDITENTRY || op == NEWSH || op == NEWPW)
 160                 switch(argc) {
 161 #ifdef YP
 162                 case 0:
 163                         GETPWUID(uid)
 164                         get_yp_master(1); /* XXX just to set the suser flag */
 165                         break;
 166                 case 1:
 167                         GETPWNAM(*argv)
 168                         get_yp_master(1); /* XXX just to set the suser flag */
 169 #else
 170                 case 0:
 171                         if (!(pw = getpwuid(uid)))
 172                                 errx(1, "unknown user: uid %u", uid);
 173                         break;
 174                 case 1:
 175                         if (!(pw = getpwnam(*argv)))
 176                                 errx(1, "unknown user: %s", *argv);
 177 #endif
 178                         if (uid && uid != pw->pw_uid)
 179                                 baduser();
 180                         break;
 181                 default:
 182                         usage();
 183                 }
 184         if (op == NEWSH) {
 185                 /* protect p_shell -- it thinks NULL is /bin/sh */
 186                 if (!arg[0])
 187                         usage();
 188                 if (p_shell(arg, pw, (ENTRY *)NULL))
 189                         pw_error((char *)NULL, 0, 1);
 190         }
 191
 192         if (op == LOADENTRY) {
 193                 if (uid)
 194                         baduser();
 195                 pw = &lpw;
 196                 if (!pw_scan(arg, pw))
 197                         exit(1);
 198         }
 199         username = pw->pw_name;
 200
 201         if (op == NEWPW) {
 202                 if (uid)
 203                         baduser();
 204
 205                 if(strchr(arg, ':')) {
 206                         errx(1, "invalid format for password");
 207                 }
 208                 pw->pw_passwd = arg;
 209         }
 210
 211         /*
 212          * The temporary file/file descriptor usage is a little tricky here.
 213          * 1:   We start off with two fd's, one for the master password
 214          *      file (used to lock everything), and one for a temporary file.
 215          * 2:   Display() gets an fp for the temporary file, and copies the
 216          *      user's information into it.  It then gives the temporary file
 217          *      to the user and closes the fp, closing the underlying fd.
 218          * 3:   The user edits the temporary file some number of times.
 219          * 4:   Verify() gets an fp for the temporary file, and verifies the
 220          *      contents.  It can't use an fp derived from the step #2 fd,
 221          *      because the user's editor may have created a new instance of
 222          *      the file.  Once the file is verified, its contents are stored
 223          *      in a password structure.  The verify routine closes the fp,
 224          *      closing the underlying fd.
 225          * 5:   Delete the temporary file.
 226          * 6:   Get a new temporary file/fd.  Pw_copy() gets an fp for it
 227          *      file and copies the master password file into it, replacing
 228          *      the user record with a new one.  We can't use the first
 229          *      temporary file for this because it was owned by the user.
 230          *      Pw_copy() closes its fp, flushing the data and closing the
 231          *      underlying file descriptor.  We can't close the master
 232          *      password fp, or we'd lose the lock.
 233          * 7:   Call pw_mkdb() (which renames the temporary file) and exit.
 234          *      The exit closes the master passwd fp/fd.
 235          */
 236         pw_init();
 237         pfd = pw_lock();
 238         tfd = pw_tmp();
 239
 240         if (op == EDITENTRY) {
 241                 display(tfd, pw);
 242                 edit(pw);
 243                 (void)unlink(tempname);
 244                 tfd = pw_tmp();
 245         }
 246
 247 #ifdef YP
 248         if (_use_yp) {
 249                 yp_submit(pw);
 250                 (void)unlink(tempname);
 251         } else {
 252 #endif /* YP */
 253         pw_copy(pfd, tfd, pw);
 254
 255         if (!pw_mkdb(username))
 256                 pw_error((char *)NULL, 0, 1);
 257 #ifdef YP
 258         }
 259 #endif /* YP */
 260         exit(0);
 261 }
 262
 263 void
 264 baduser()
 265 {
 266         errx(1, "%s", strerror(EACCES));
 267 }
 268
 269 void
 270 usage()
 271 {
 272
 273         (void)fprintf(stderr,
 274 #ifdef YP
 275                 "usage: chpass [-l] [-y] [-d domain [-h host]] [-a list] [-p encpass] [-s shell] [user]\n");
 276 #else
 277                 "usage: chpass [-a list] [-p encpass] [-s shell] [user]\n");
 278 #endif
 279         exit(1);
 280 }