NetBSD/lib/libutil/passwd.c

338 lines
8.0 KiB
C

/* $NetBSD: passwd.c,v 1.19 1999/12/03 16:23:58 mjl Exp $ */
/*
* Copyright (c) 1987, 1993, 1994, 1995
* 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.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: passwd.c,v 1.19 1999/12/03 16:23:58 mjl Exp $");
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <assert.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <util.h>
static void pw_cont __P((int sig));
static int pw_equal __P((char *buf, struct passwd *old_pw));
int
pw_lock(retries)
int retries;
{
int i, fd;
mode_t old_mode;
int oerrno;
/* Acquire the lock file. */
old_mode = umask(0);
fd = open(_PATH_MASTERPASSWD_LOCK, O_WRONLY|O_CREAT|O_EXCL, 0600);
for (i = 0; i < retries && fd < 0 && errno == EEXIST; i++) {
sleep(1);
fd = open(_PATH_MASTERPASSWD_LOCK, O_WRONLY|O_CREAT|O_EXCL,
0600);
}
oerrno = errno;
(void)umask(old_mode);
errno = oerrno;
return(fd);
}
int
pw_mkdb()
{
int pstat;
pid_t pid;
pid = vfork();
if (pid == -1)
return (-1);
if (pid == 0) {
execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p",
_PATH_MASTERPASSWD_LOCK, NULL);
_exit(1);
}
pid = waitpid(pid, &pstat, 0);
if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
return(-1);
return(0);
}
int
pw_abort()
{
return(unlink(_PATH_MASTERPASSWD_LOCK));
}
/* Everything below this point is intended for the convenience of programs
* which allow a user to interactively edit the passwd file. Errors in the
* routines below will cause the process to abort. */
static pid_t editpid = -1;
static 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);
}
void
pw_edit(notsetuid, filename)
int notsetuid;
const char *filename;
{
int pstat;
char *p, *editor;
char *argp[] = { "sh", "-c", NULL, NULL };
#ifdef __GNUC__
(void) &editor;
#endif
if (filename == NULL)
filename = _PATH_MASTERPASSWD_LOCK;
if ((editor = getenv("EDITOR")) == NULL)
editor = _PATH_VI;
p = malloc(strlen(editor) + 1 + strlen(filename) + 1);
if (p == NULL)
return;
sprintf(p, "%s %s", editor, filename);
argp[2] = p;
switch(editpid = vfork()) {
case -1:
free(p);
return;
case 0:
if (notsetuid) {
setgid(getgid());
setuid(getuid());
}
execvp(_PATH_BSHELL, argp);
_exit(1);
}
free(p);
for (;;) {
editpid = waitpid(editpid, (int *)&pstat, WUNTRACED);
if (editpid == -1)
pw_error(editor, 1, 1);
else if (WIFSTOPPED(pstat))
raise(WSTOPSIG(pstat));
else if (WIFEXITED(pstat) && WEXITSTATUS(pstat) == 0)
break;
else
pw_error(editor, 1, 1);
}
editpid = -1;
}
void
pw_prompt()
{
int c;
(void)printf("re-edit the password file? [y]: ");
(void)fflush(stdout);
c = getchar();
if (c != EOF && c != '\n')
while (getchar() != '\n');
if (c == 'n')
pw_error(NULL, 0, 0);
}
/* for use in pw_copy(). Compare a pw entry to a pw struct. */
static int
pw_equal (buf, pw)
char *buf;
struct passwd *pw;
{
struct passwd buf_pw;
int len;
_DIAGASSERT(buf != NULL);
_DIAGASSERT(pw != NULL);
len = strlen (buf);
if (buf[len-1] == '\n')
buf[len-1] = '\0';
if (!pw_scan(buf, &buf_pw, NULL))
return 0;
return !strcmp(pw->pw_name, buf_pw.pw_name)
&& pw->pw_uid == buf_pw.pw_uid
&& pw->pw_gid == buf_pw.pw_gid
&& !strcmp(pw->pw_class, buf_pw.pw_class)
&& (long)pw->pw_change == (long)buf_pw.pw_change
&& (long)pw->pw_expire == (long)buf_pw.pw_expire
&& !strcmp(pw->pw_gecos, buf_pw.pw_gecos)
&& !strcmp(pw->pw_dir, buf_pw.pw_dir)
&& !strcmp(pw->pw_shell, buf_pw.pw_shell);
}
void
pw_copy(ffd, tfd, pw, old_pw)
int ffd, tfd;
struct passwd *pw, *old_pw;
{
FILE *from, *to;
int done;
char *p, buf[8192];
_DIAGASSERT(pw != NULL);
/* old_pw may be NULL */
if (!(from = fdopen(ffd, "r")))
pw_error(_PATH_MASTERPASSWD, 1, 1);
if (!(to = fdopen(tfd, "w")))
pw_error(_PATH_MASTERPASSWD_LOCK, 1, 1);
for (done = 0; fgets(buf, sizeof(buf), from);) {
if (!strchr(buf, '\n')) {
warnx("%s: line too long", _PATH_MASTERPASSWD);
pw_error(NULL, 0, 1);
}
if (done) {
(void)fprintf(to, "%s", buf);
if (ferror(to))
goto err;
continue;
}
if (!(p = strchr(buf, ':'))) {
warnx("%s: corrupted entry", _PATH_MASTERPASSWD);
pw_error(NULL, 0, 1);
}
*p = '\0';
if (strcmp(buf, pw->pw_name)) {
*p = ':';
(void)fprintf(to, "%s", buf);
if (ferror(to))
goto err;
continue;
}
*p = ':';
if (old_pw && !pw_equal(buf, old_pw)) {
warnx("%s: entry inconsistent",
_PATH_MASTERPASSWD);
pw_error(NULL, 0, 1);
}
(void)fprintf(to, "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n",
pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid,
pw->pw_class, (long)pw->pw_change, (long)pw->pw_expire,
pw->pw_gecos, pw->pw_dir, pw->pw_shell);
done = 1;
if (ferror(to))
goto err;
}
/* Only append a new entry if real uid is root! */
if (!done) {
if (getuid() == 0)
(void)fprintf(to, "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n",
pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid,
pw->pw_class, (long)pw->pw_change,
(long)pw->pw_expire, pw->pw_gecos, pw->pw_dir,
pw->pw_shell);
else
warnx("%s: changes not made, no such entry",
_PATH_MASTERPASSWD);
}
if (ferror(to))
err: pw_error(NULL, 1, 1);
(void)fclose(to);
}
void
pw_error(name, err, eval)
const char *name;
int err, eval;
{
if (err)
warn(name);
warnx("%s: unchanged", _PATH_MASTERPASSWD);
pw_abort();
exit(eval);
}