chpass.tproj/chpass.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.0 (the 'License').  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License."
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*-
  25  * Copyright (c) 1990, 1993, 1994
  26  *      The Regents of the University of California.  All rights reserved.
  27  *
  28  * Redistribution and use in source and binary forms, with or without
  29  * modification, are permitted provided that the following conditions
  30  * are met:
  31  * 1. Redistributions of source code must retain the above copyright
  32  *    notice, this list of conditions and the following disclaimer.
  33  * 2. Redistributions in binary form must reproduce the above copyright
  34  *    notice, this list of conditions and the following disclaimer in the
  35  *    documentation and/or other materials provided with the distribution.
  36  * 3. All advertising materials mentioning features or use of this software
  37  *    must display the following acknowledgement:
  38  *      This product includes software developed by the University of
  39  *      California, Berkeley and its contributors.
  40  * 4. Neither the name of the University nor the names of its contributors
  41  *    may be used to endorse or promote products derived from this software
  42  *    without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  45  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  47  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  48  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  49  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  50  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  51  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  52  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  53  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  54  * SUCH DAMAGE.
  55  */
  56
  57 #ifndef lint
  58 static char copyright[] =
  59 "@(#) Copyright (c) 1988, 1993, 1994\n\
  60         The Regents of the University of California.  All rights reserved.\n";
  61 #endif /* not lint */
  62
  63 #include <sys/param.h>
  64 #include <sys/stat.h>
  65 #include <sys/signal.h>
  66 #include <sys/time.h>
  67 #include <sys/resource.h>
  68
  69 #include <ctype.h>
  70 #include <err.h>
  71 #include <errno.h>
  72 #include <fcntl.h>
  73 #include <pwd.h>
  74 #include <stdio.h>
  75 #include <stdlib.h>
  76 #include <string.h>
  77 #include <unistd.h>
  78
  79 #include <pw_scan.h>
  80 #include <pw_util.h>
  81 #include "pw_copy.h"
  82
  83 #include "chpass.h"
  84 #include "pathnames.h"
  85
  86 char *progname = "chpass";
  87 char *tempname;
  88 uid_t uid;
  89
  90 void    baduser __P((void));
  91 void    usage __P((void));
  92
  93 int
  94 main(argc, argv)
  95         int argc;
  96         char **argv;
  97 {
  98         enum { NEWSH, LOADENTRY, EDITENTRY } op;
  99         struct passwd *pw, lpw;
 100         int ch, pfd, tfd;
 101         char *arg;
 102
 103         op = EDITENTRY;
 104         while ((ch = getopt(argc, argv, "a:s:")) != EOF)
 105                 switch(ch) {
 106                 case 'a':
 107                         op = LOADENTRY;
 108                         arg = optarg;
 109                         break;
 110                 case 's':
 111                         op = NEWSH;
 112                         arg = optarg;
 113                         break;
 114                 case '?':
 115                 default:
 116                         usage();
 117                 }
 118         argc -= optind;
 119         argv += optind;
 120
 121         uid = getuid();
 122
 123         if (op == EDITENTRY || op == NEWSH)
 124                 switch(argc) {
 125                 case 0:
 126                         if (!(pw = getpwuid(uid)))
 127                                 errx(1, "unknown user: uid %u", uid);
 128                         break;
 129                 case 1:
 130                         if (!(pw = getpwnam(*argv)))
 131                                 errx(1, "unknown user: %s", *argv);
 132                         if (uid && uid != pw->pw_uid)
 133                                 baduser();
 134                         break;
 135                 default:
 136                         usage();
 137                 }
 138
 139         if (op == NEWSH) {
 140                 /* protect p_shell -- it thinks NULL is /bin/sh */
 141                 if (!arg[0])
 142                         usage();
 143                 if (p_shell(arg, pw, (ENTRY *)NULL))
 144                         pw_error((char *)NULL, 0, 1);
 145         }
 146
 147         if (op == LOADENTRY) {
 148                 if (uid)
 149                         baduser();
 150                 pw = &lpw;
 151                 if (!pw_scan(arg, pw))
 152                         exit(1);
 153         }
 154
 155         /*
 156          * The temporary file/file descriptor usage is a little tricky here.
 157          * 1:   We start off with two fd's, one for the master password
 158          *      file (used to lock everything), and one for a temporary file.
 159          * 2:   Display() gets an fp for the temporary file, and copies the
 160          *      user's information into it.  It then gives the temporary file
 161          *      to the user and closes the fp, closing the underlying fd.
 162          * 3:   The user edits the temporary file some number of times.
 163          * 4:   Verify() gets an fp for the temporary file, and verifies the
 164          *      contents.  It can't use an fp derived from the step #2 fd,
 165          *      because the user's editor may have created a new instance of
 166          *      the file.  Once the file is verified, its contents are stored
 167          *      in a password structure.  The verify routine closes the fp,
 168          *      closing the underlying fd.
 169          * 5:   Delete the temporary file.
 170          * 6:   Get a new temporary file/fd.  Pw_copy() gets an fp for it
 171          *      file and copies the master password file into it, replacing
 172          *      the user record with a new one.  We can't use the first
 173          *      temporary file for this because it was owned by the user.
 174          *      Pw_copy() closes its fp, flushing the data and closing the
 175          *      underlying file descriptor.  We can't close the master
 176          *      password fp, or we'd lose the lock.
 177          * 7:   Call pw_mkdb() (which renames the temporary file) and exit.
 178          *      The exit closes the master passwd fp/fd.
 179          */
 180         pw_init();
 181         pfd = pw_lock();
 182         tfd = pw_tmp();
 183
 184         if (op == EDITENTRY) {
 185                 display(tfd, pw);
 186                 edit(pw);
 187                 (void)unlink(tempname);
 188                 tfd = pw_tmp();
 189         }
 190
 191         pw_copy(pfd, tfd, pw);
 192
 193         if (!pw_mkdb())
 194                 pw_error((char *)NULL, 0, 1);
 195         exit(0);
 196 }
 197
 198 void
 199 baduser()
 200 {
 201
 202         errx(1, "%s", strerror(EACCES));
 203 }
 204
 205 void
 206 usage()
 207 {
 208
 209         (void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [user]\n");
 210         exit(1);
 211 }