xref: /freebsd/sbin/mknod/mknod.c (revision 1db64f89363c97858961c4df0b7d02f3223723cf)
1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Kevin Fall.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/stat.h>
37 
38 #include <err.h>
39 #include <errno.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <unistd.h>
43 #include <grp.h>
44 #include <pwd.h>
45 #include <string.h>
46 
47 static void
48 usage(void)
49 {
50 
51 	(void)fprintf(stderr,
52 	    "usage: mknod name\n"
53 	    "       mknod name [b | c] major minor [owner:group]\n");
54 	exit(1);
55 }
56 
57 static u_long
58 id(const char *name, const char *type)
59 {
60 	u_long val;
61 	char *ep;
62 
63 	/*
64 	 * XXX
65 	 * We know that uid_t's and gid_t's are unsigned longs.
66 	 */
67 	errno = 0;
68 	val = strtoul(name, &ep, 10);
69 	if (errno)
70 		err(1, "%s", name);
71 	if (*ep != '\0')
72 		errx(1, "%s: illegal %s name", name, type);
73 	return (val);
74 }
75 
76 static gid_t
77 a_gid(const char *s)
78 {
79 	struct group *gr;
80 
81 	if (*s == '\0')			/* Argument was "uid[:.]". */
82 		errx(1, "group must be specified when the owner is");
83 	return ((gr = getgrnam(s)) == NULL) ? id(s, "group") : gr->gr_gid;
84 }
85 
86 static uid_t
87 a_uid(const char *s)
88 {
89 	struct passwd *pw;
90 
91 	if (*s == '\0')			/* Argument was "[:.]gid". */
92 		errx(1, "owner must be specified when the group is");
93 	return ((pw = getpwnam(s)) == NULL) ? id(s, "user") : pw->pw_uid;
94 }
95 
96 int
97 main(int argc, char **argv)
98 {
99 	int range_error;
100 	uid_t uid;
101 	gid_t gid;
102 	mode_t mode;
103 	dev_t dev;
104 	char *cp, *endp;
105 	long mymajor, myminor;
106 
107 	if (argc != 2 && argc != 5 && argc != 6)
108 		usage();
109 
110 	if (argc >= 5) {
111 		mode = 0666;
112 		if (argv[2][0] == 'c')
113 			mode |= S_IFCHR;
114 		else if (argv[2][0] == 'b')
115 			mode |= S_IFBLK;
116 		else
117 			errx(1, "node must be type 'b' or 'c'");
118 
119 		errno = 0;
120 		mymajor = (long)strtoul(argv[3], &endp, 0);
121 		if (endp == argv[3] || *endp != '\0')
122 			errx(1, "%s: non-numeric major number", argv[3]);
123 		range_error = errno;
124 		errno = 0;
125 		myminor = (long)strtoul(argv[4], &endp, 0);
126 		if (endp == argv[4] || *endp != '\0')
127 			errx(1, "%s: non-numeric minor number", argv[4]);
128 		range_error |= errno;
129 		dev = makedev(mymajor, myminor);
130 		if (range_error || major(dev) != mymajor ||
131 		    (long)(u_int)minor(dev) != myminor)
132 			errx(1, "major or minor number too large");
133 	} else {
134 		mode = 0666 | S_IFCHR;
135 		dev = 0;
136 	}
137 
138 	uid = gid = -1;
139 	if (6 == argc) {
140 	    	/* have owner:group */
141 		if ((cp = strchr(argv[5], ':')) != NULL) {
142 			*cp++ = '\0';
143 			gid = a_gid(cp);
144 		} else
145 		usage();
146 		uid = a_uid(argv[5]);
147 	}
148 
149 	if (mknod(argv[1], mode, dev) != 0)
150 		err(1, "%s", argv[1]);
151 	if (6 == argc)
152 		if (chown(argv[1], uid, gid))
153 			err(1, "setting ownership on %s", argv[1]);
154 	exit(0);
155 }
156