1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
/*-
* Copyright (c) 1999 Berkeley Software Design, Inc. 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. Berkeley Software Design Inc's name may not be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``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 BERKELEY SOFTWARE DESIGN INC 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.
*
* From BSDI: daemon.c,v 1.2 1996/08/15 01:11:09 jch Exp
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <err.h>
#include <errno.h>
#include <pwd.h>
#include <libutil.h>
#include <login_cap.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
static void restrict_process(const char *);
static void usage(void);
int
main(int argc, char *argv[])
{
struct pidfh *pfh = NULL;
int ch, nochdir, noclose, errcode;
const char *pidfile, *user;
pid_t otherpid;
nochdir = noclose = 1;
pidfile = user = NULL;
while ((ch = getopt(argc, argv, "-cfp:u:")) != -1) {
switch (ch) {
case 'c':
nochdir = 0;
break;
case 'f':
noclose = 0;
break;
case 'p':
pidfile = optarg;
break;
case 'u':
user = optarg;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (argc == 0)
usage();
/*
* Try to open the pidfile before calling daemon(3),
* to be able to report the error intelligently
*/
if (pidfile) {
pfh = pidfile_open(pidfile, 0600, &otherpid);
if (pfh == NULL) {
if (errno == EEXIST) {
errx(3, "process already running, pid: %d",
otherpid);
}
err(2, "pidfile ``%s''", pidfile);
}
}
if (user != NULL)
restrict_process(user);
if (daemon(nochdir, noclose) == -1)
err(1, NULL);
/* Now that we are the child, write out the pid */
if (pidfile)
pidfile_write(pfh);
execvp(argv[0], argv);
/*
* execvp() failed -- unlink pidfile if any, and
* report the error
*/
errcode = errno; /* Preserve errcode -- unlink may reset it */
if (pidfile)
pidfile_remove(pfh);
/* The child is now running, so the exit status doesn't matter. */
errc(1, errcode, "%s", argv[0]);
}
static void
restrict_process(const char *user)
{
struct passwd *pw = NULL;
pw = getpwnam(user);
if (pw == NULL)
errx(1, "unknown user: %s", user);
if (setusercontext(NULL, pw, pw->pw_uid, LOGIN_SETALL) != 0)
errx(1, "failed to set user environment");
}
static void
usage(void)
{
(void)fprintf(stderr,
"usage: daemon [-cf] [-p pidfile] [-u user] command "
"arguments ...\n");
exit(1);
}
|
