freebsd-dev/usr.sbin/pw/pwupd.c
Alan Somers cbaba16b23 Speed up pw operations that edit /etc/group or /etc/passwd
r285050 fixed a bug in pw that could lead to /etc/passwd or /etc/group
corruption on power loss. However, it fixed it by opening those files with
O_SYNC, which is very slow, especially on ZFS. This change replaces O_SYNC
with appropriately placed fsync()s instead, which is much faster. Using a
ZFS tmpdir, the time to run pw's kyua tests drops from 245s to 35s.

Reviewed by:	allanjude, bapt, vangyzen, garga
Tested on pfSense by:	garga
MFC after:	4 weeks
Sponsored by:	Spectra Logic Corp
Differential Revision:	https://reviews.freebsd.org/D8319
2016-11-18 16:07:08 +00:00

153 lines
3.3 KiB
C

/*-
* Copyright (C) 1996
* David L. Nugent. 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.
*
* THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT 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 DAVID L. NUGENT 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
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/wait.h>
#include <err.h>
#include <errno.h>
#include <pwd.h>
#include <libutil.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "pwupd.h"
char *
getpwpath(char const * file)
{
static char pathbuf[MAXPATHLEN];
snprintf(pathbuf, sizeof pathbuf, "%s/%s", conf.etcpath, file);
return (pathbuf);
}
static int
pwdb_check(void)
{
int i = 0;
pid_t pid;
char *args[10];
args[i++] = _PATH_PWD_MKDB;
args[i++] = "-C";
if (strcmp(conf.etcpath, _PATH_PWD) != 0) {
args[i++] = "-d";
args[i++] = conf.etcpath;
}
args[i++] = getpwpath(_MASTERPASSWD);
args[i] = NULL;
if ((pid = fork()) == -1) /* Error (errno set) */
i = errno;
else if (pid == 0) { /* Child */
execv(args[0], args);
_exit(1);
} else { /* Parent */
waitpid(pid, &i, 0);
if (WEXITSTATUS(i))
i = EIO;
}
return (i);
}
static int
pw_update(struct passwd * pwd, char const * user)
{
struct passwd *pw = NULL;
struct passwd *old_pw = NULL;
int rc, pfd, tfd;
if ((rc = pwdb_check()) != 0)
return (rc);
if (pwd != NULL)
pw = pw_dup(pwd);
if (user != NULL)
old_pw = GETPWNAM(user);
if (pw_init(conf.etcpath, NULL))
err(1, "pw_init()");
if ((pfd = pw_lock()) == -1) {
pw_fini();
err(1, "pw_lock()");
}
if ((tfd = pw_tmp(-1)) == -1) {
pw_fini();
err(1, "pw_tmp()");
}
if (pw_copy(pfd, tfd, pw, old_pw) == -1) {
pw_fini();
close(tfd);
err(1, "pw_copy()");
}
fsync(tfd);
close(tfd);
/*
* in case of deletion of a user, the whole database
* needs to be regenerated
*/
if (pw_mkdb(pw != NULL ? pw->pw_name : NULL) == -1) {
pw_fini();
err(1, "pw_mkdb()");
}
free(pw);
pw_fini();
return (0);
}
int
addpwent(struct passwd * pwd)
{
return (pw_update(pwd, NULL));
}
int
chgpwent(char const * login, struct passwd * pwd)
{
return (pw_update(pwd, login));
}
int
delpwent(struct passwd * pwd)
{
return (pw_update(NULL, pwd->pw_name));
}