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 static pid_t editpid = -1;
  64 static int lockfd;
  65
  66 void
  67 pw_cont(sig)
  68         int sig;
  69 {
  70
  71         if (editpid != -1)
  72                 kill(editpid, sig);
  73 }
  74
  75 void
  76 pw_init()
  77 {
  78         struct rlimit rlim;
  79
  80         /* Unlimited resource limits. */
  81         rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
  82         (void)setrlimit(RLIMIT_CPU, &rlim);
  83         (void)setrlimit(RLIMIT_FSIZE, &rlim);
  84         (void)setrlimit(RLIMIT_STACK, &rlim);
  85         (void)setrlimit(RLIMIT_DATA, &rlim);
  86         (void)setrlimit(RLIMIT_RSS, &rlim);
  87
  88         /* Don't drop core (not really necessary, but GP's). */
  89         rlim.rlim_cur = rlim.rlim_max = 0;
  90         (void)setrlimit(RLIMIT_CORE, &rlim);
  91
  92         /* Turn off signals. */
  93         (void)signal(SIGALRM, SIG_IGN);
  94         (void)signal(SIGHUP, SIG_IGN);
  95         (void)signal(SIGINT, SIG_IGN);
  96         (void)signal(SIGPIPE, SIG_IGN);
  97         (void)signal(SIGQUIT, SIG_IGN);
  98         (void)signal(SIGTERM, SIG_IGN);
  99         (void)signal(SIGCONT, pw_cont);
 100
 101         /* Create with exact permissions. */
 102         (void)umask(0);
 103 }
 104
 105 int
 106 pw_lock()
 107 {
 108         /*
 109          * If the master password file doesn't exist, the system is hosed.
 110          * Might as well try to build one.  Set the close-on-exec bit so
 111          * that users can't get at the encrypted passwords while editing.
 112          * Open should allow flock'ing the file; see 4.4BSD.    XXX
 113          */
 114         lockfd = open(_PATH_MASTERPASSWD, O_RDONLY, 0);
 115         if (lockfd < 0 || fcntl(lockfd, F_SETFD, 1) == -1)
 116                 err(1, "%s", _PATH_MASTERPASSWD);
 117         if (flock(lockfd, LOCK_EX|LOCK_NB))
 118                 errx(1, "the password db file is busy");
 119         return (lockfd);
 120 }
 121
 122 int
 123 pw_tmp()
 124 {
 125         static char path[MAXPATHLEN] = _PATH_MASTERPASSWD;
 126         int fd;
 127         char *p;
 128
 129         if (p = strrchr(path, '/'))
 130                 ++p;
 131         else
 132                 p = path;
 133         strcpy(p, "pw.XXXXXX");
 134         if ((fd = mkstemp(path)) == -1)
 135                 err(1, "%s", path);
 136         tempname = path;
 137         return (fd);
 138 }
 139
 140 int
 141 pw_mkdb()
 142 {
 143         int pstat;
 144         pid_t pid;
 145
 146         warnx("rebuilding the database...");
 147         (void)fflush(stderr);
 148         if (!(pid = vfork())) {
 149                 execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", tempname, NULL);
 150                 pw_error(_PATH_PWD_MKDB, 1, 1);
 151         }
 152         pid = waitpid(pid, &pstat, 0);
 153         if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
 154                 return (0);
 155         warnx("done");
 156         return (1);
 157 }
 158
 159 void
 160 pw_edit(notsetuid)
 161         int notsetuid;
 162 {
 163         int pstat;
 164         char *p, *editor;
 165
 166         if (!(editor = getenv("EDITOR")))
 167                 editor = _PATH_VI;
 168         if (p = strrchr(editor, '/'))
 169                 ++p;
 170         else
 171                 p = editor;
 172
 173         if (!(editpid = vfork())) {
 174                 if (notsetuid) {
 175                         (void)setgid(getgid());
 176                         (void)setuid(getuid());
 177                 }
 178                 execlp(editor, p, tempname, NULL);
 179                 _exit(1);
 180         }
 181         for (;;) {
 182                 editpid = waitpid(editpid, (int *)&pstat, WUNTRACED);
 183                 if (editpid == -1)
 184                         pw_error(editor, 1, 1);
 185                 else if (WIFSTOPPED(pstat))
 186                         raise(WSTOPSIG(pstat));
 187                 else if (WIFEXITED(pstat) && WEXITSTATUS(pstat) == 0)
 188                         break;
 189                 else
 190                         pw_error(editor, 1, 1);
 191         }
 192         editpid = -1;
 193 }
 194
 195 void
 196 pw_prompt()
 197 {
 198         int c;
 199
 200         (void)printf("re-edit the password file? [y]: ");
 201         (void)fflush(stdout);
 202         c = getchar();
 203         if (c != EOF && c != '\n')
 204                 while (getchar() != '\n');
 205         if (c == 'n')
 206                 pw_error(NULL, 0, 0);
 207 }
 208
 209 void
 210 pw_error(name, err, eval)
 211         char *name;
 212         int err, eval;
 213 {
 214         if (err)
 215                 warn(name);
 216
 217         warnx("%s: unchanged", _PATH_MASTERPASSWD);
 218         (void)unlink(tempname);
 219         exit(eval);
 220 }