libutil/pw_util.c

   1 /*-
   2  * Copyright (c) 1990, 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 sccsid[] = "@(#)pw_util.c   8.3 (Berkeley) 4/2/94";
  36 #endif /* not lint */
  37
  38 /*
  39  * This file is used by all the "password" programs; vipw(8), chpass(1),
  40  * and passwd(1).
  41  */
  42
  43 #include <sys/param.h>
  44 #include <sys/time.h>
  45 #include <sys/resource.h>
  46 #include <sys/stat.h>
  47 #include <sys/wait.h>
  48
  49 #include <err.h>
  50 #include <errno.h>
  51 #include <fcntl.h>
  52 #include <paths.h>
  53 #include <pwd.h>
  54 #include <signal.h>
  55 #include <stdio.h>
  56 #include <stdlib.h>
  57 #include <string.h>
  58 #include <unistd.h>
  59
  60 #include "pw_util.h"
  61
  62 extern char *tempname;
  63
  64 void
  65 pw_init()
  66 {
  67         struct rlimit rlim;
  68
  69         /* Unlimited resource limits. */
  70         rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
  71         (void)setrlimit(RLIMIT_CPU, &rlim);
  72         (void)setrlimit(RLIMIT_FSIZE, &rlim);
  73         (void)setrlimit(RLIMIT_STACK, &rlim);
  74         (void)setrlimit(RLIMIT_DATA, &rlim);
  75         (void)setrlimit(RLIMIT_RSS, &rlim);
  76
  77         /* Don't drop core (not really necessary, but GP's). */
  78         rlim.rlim_cur = rlim.rlim_max = 0;
  79         (void)setrlimit(RLIMIT_CORE, &rlim);
  80
  81         /* Turn off signals. */
  82         (void)signal(SIGALRM, SIG_IGN);
  83         (void)signal(SIGHUP, SIG_IGN);
  84         (void)signal(SIGINT, SIG_IGN);
  85         (void)signal(SIGPIPE, SIG_IGN);
  86         (void)signal(SIGQUIT, SIG_IGN);
  87         (void)signal(SIGTERM, SIG_IGN);
  88         (void)signal(SIGTSTP, SIG_IGN);
  89         (void)signal(SIGTTOU, SIG_IGN);
  90
  91         /* Create with exact permissions. */
  92         (void)umask(0);
  93 }
  94
  95 static int lockfd;
  96
  97 int
  98 pw_lock()
  99 {
 100         /*
 101          * If the master password file doesn't exist, the system is hosed.
 102          * Might as well try to build one.  Set the close-on-exec bit so
 103          * that users can't get at the encrypted passwords while editing.
 104          * Open should allow flock'ing the file; see 4.4BSD.    XXX
 105          */
 106         lockfd = open(_PATH_MASTERPASSWD, O_RDONLY, 0);
 107         if (lockfd < 0 || fcntl(lockfd, F_SETFD, 1) == -1)
 108                 err(1, "%s", _PATH_MASTERPASSWD);
 109         if (flock(lockfd, LOCK_EX|LOCK_NB))
 110                 errx(1, "the password db file is busy");
 111         return (lockfd);
 112 }
 113
 114 int
 115 pw_tmp()
 116 {
 117         static char path[MAXPATHLEN] = _PATH_MASTERPASSWD;
 118         int fd;
 119         char *p;
 120
 121         if (p = strrchr(path, '/'))
 122                 ++p;
 123         else
 124                 p = path;
 125         strcpy(p, "pw.XXXXXX");
 126         if ((fd = mkstemp(path)) == -1)
 127                 err(1, "%s", path);
 128         tempname = path;
 129         return (fd);
 130 }
 131
 132 int
 133 pw_mkdb()
 134 {
 135         int pstat;
 136         pid_t pid;
 137
 138         warnx("rebuilding the database...");
 139         (void)fflush(stderr);
 140         if (!(pid = vfork())) {
 141                 execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", tempname, NULL);
 142                 pw_error(_PATH_PWD_MKDB, 1, 1);
 143         }
 144         pid = waitpid(pid, &pstat, 0);
 145         if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
 146                 return (0);
 147         warnx("done");
 148         return (1);
 149 }
 150
 151 void
 152 pw_edit(notsetuid)
 153         int notsetuid;
 154 {
 155         int pstat;
 156         pid_t pid;
 157         char *p, *editor;
 158
 159         if (!(editor = getenv("EDITOR")))
 160                 editor = _PATH_VI;
 161         if (p = strrchr(editor, '/'))
 162                 ++p;
 163         else
 164                 p = editor;
 165
 166         if (!(pid = vfork())) {
 167                 if (notsetuid) {
 168                         (void)setgid(getgid());
 169                         (void)setuid(getuid());
 170                 }
 171                 execlp(editor, p, tempname, NULL);
 172                 _exit(1);
 173         }
 174         pid = waitpid(pid, (int *)&pstat, 0);
 175         if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
 176                 pw_error(editor, 1, 1);
 177 }
 178
 179 void
 180 pw_prompt()
 181 {
 182         int c;
 183
 184         (void)printf("re-edit the password file? [y]: ");
 185         (void)fflush(stdout);
 186         c = getchar();
 187         if (c != EOF && c != '\n')
 188                 while (getchar() != '\n');
 189         if (c == 'n')
 190                 pw_error(NULL, 0, 0);
 191 }
 192
 193 void
 194 pw_error(name, err, eval)
 195         char *name;
 196         int err, eval;
 197 {
 198         if (err)
 199                 warn(name);
 200
 201         warnx("%s: unchanged", _PATH_MASTERPASSWD);
 202         (void)unlink(tempname);
 203         exit(eval);
 204 }