freebsd-skq/lib/libutil/pw_util.c
Pierre Beyssac 2ece3ed4c8 Force umask to 077 (instead of 000) during the edit phase, to get
secure permissions in case the user attempts to save something to
a file of his own.

Move umask stuff out of pw_init() into main() for better visibility
of overall umask tweaking logic.

PR:		misc/11797
1999-06-26 12:15:39 +00:00

260 lines
6.2 KiB
C

/*-
* Copyright (c) 1990, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
#if 0
static const char sccsid[] = "@(#)pw_util.c 8.3 (Berkeley) 4/2/94";
#endif
static const char rcsid[] =
"$Id: pw_util.c,v 1.14 1999/06/26 07:16:38 sheldonh Exp $";
#endif /* not lint */
/*
* This file is used by all the "password" programs; vipw(8), chpass(1),
* and passwd(1).
*/
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <err.h>
#include <fcntl.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "pw_util.h"
extern char *tempname;
static pid_t editpid = -1;
static int lockfd;
char *mppath = _PATH_PWD;
char *masterpasswd = _PATH_MASTERPASSWD;
void
pw_cont(sig)
int sig;
{
if (editpid != -1)
kill(editpid, sig);
}
void
pw_init()
{
struct rlimit rlim;
/* Unlimited resource limits. */
rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
(void)setrlimit(RLIMIT_CPU, &rlim);
(void)setrlimit(RLIMIT_FSIZE, &rlim);
(void)setrlimit(RLIMIT_STACK, &rlim);
(void)setrlimit(RLIMIT_DATA, &rlim);
(void)setrlimit(RLIMIT_RSS, &rlim);
/* Don't drop core (not really necessary, but GP's). */
rlim.rlim_cur = rlim.rlim_max = 0;
(void)setrlimit(RLIMIT_CORE, &rlim);
/* Turn off signals. */
(void)signal(SIGALRM, SIG_IGN);
(void)signal(SIGHUP, SIG_IGN);
(void)signal(SIGINT, SIG_IGN);
(void)signal(SIGPIPE, SIG_IGN);
(void)signal(SIGQUIT, SIG_IGN);
(void)signal(SIGTERM, SIG_IGN);
(void)signal(SIGCONT, pw_cont);
}
int
pw_lock()
{
/*
* If the master password file doesn't exist, the system is hosed.
* Might as well try to build one. Set the close-on-exec bit so
* that users can't get at the encrypted passwords while editing.
* Open should allow flock'ing the file; see 4.4BSD. XXX
*/
for (;;) {
struct stat st;
lockfd = open(masterpasswd, O_RDONLY, 0);
if (lockfd < 0 || fcntl(lockfd, F_SETFD, 1) == -1)
err(1, "%s", masterpasswd);
if (flock(lockfd, LOCK_EX|LOCK_NB))
errx(1, "the password db file is busy");
/*
* If the password file was replaced while we were trying to
* get the lock, our hardlink count will be 0 and we have to
* close and retry.
*/
if (fstat(lockfd, &st) < 0)
errx(1, "fstat() failed");
if (st.st_nlink != 0)
break;
close(lockfd);
lockfd = -1;
}
return (lockfd);
}
int
pw_tmp()
{
static char path[MAXPATHLEN];
int fd;
char *p;
strncpy(path, masterpasswd, MAXPATHLEN - 1);
path[MAXPATHLEN] = '\0';
if ((p = strrchr(path, '/')))
++p;
else
p = path;
strcpy(p, "pw.XXXXXX");
if ((fd = mkstemp(path)) == -1)
err(1, "%s", path);
tempname = path;
return (fd);
}
int
pw_mkdb(username)
char *username;
{
int pstat;
pid_t pid;
(void)fflush(stderr);
if (!(pid = fork())) {
if(!username) {
warnx("rebuilding the database...");
execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", "-d", mppath,
tempname, NULL);
} else {
warnx("updating the database...");
execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", "-d", mppath,
"-u", username, tempname, NULL);
}
pw_error(_PATH_PWD_MKDB, 1, 1);
}
pid = waitpid(pid, &pstat, 0);
if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
return (0);
warnx("done");
return (1);
}
void
pw_edit(notsetuid)
int notsetuid;
{
int pstat;
char *p, *editor;
if (!(editor = getenv("EDITOR")))
editor = _PATH_VI;
if ((p = strrchr(editor, '/')))
++p;
else
p = editor;
if (!(editpid = fork())) {
if (notsetuid) {
(void)setgid(getgid());
(void)setuid(getuid());
}
errno = 0;
execlp(editor, p, tempname, NULL);
_exit(errno);
}
for (;;) {
editpid = waitpid(editpid, (int *)&pstat, WUNTRACED);
errno = WEXITSTATUS(pstat);
if (editpid == -1)
pw_error(editor, 1, 1);
else if (WIFSTOPPED(pstat))
raise(WSTOPSIG(pstat));
else if (WIFEXITED(pstat) && errno == 0)
break;
else
pw_error(editor, 1, 1);
}
editpid = -1;
}
void
pw_prompt()
{
int c, first;
(void)printf("re-edit the password file? [y]: ");
(void)fflush(stdout);
first = c = getchar();
while (c != '\n' && c != EOF)
c = getchar();
if (first == 'n')
pw_error(NULL, 0, 0);
}
void
pw_error(name, err, eval)
char *name;
int err, eval;
{
#ifdef YP
extern int _use_yp;
#endif /* YP */
if (err)
warn(name);
#ifdef YP
if (_use_yp)
warnx("NIS information unchanged");
else
#endif /* YP */
warnx("%s: unchanged", masterpasswd);
(void)unlink(tempname);
exit(eval);
}