xref: /dragonfly/usr.sbin/chkgrp/chkgrp.c (revision 1de703da)
1 /*-
2  * Copyright (c) 1998 Dag-Erling Co�dan Sm�rgrav
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  * $FreeBSD: src/usr.sbin/chkgrp/chkgrp.c,v 1.3.2.2 2001/07/12 22:57:35 mjacob Exp $
29  * $DragonFly: src/usr.sbin/chkgrp/chkgrp.c,v 1.2 2003/06/17 04:29:52 dillon Exp $
30  */
31 
32 #include <err.h>
33 #include <ctype.h>
34 #include <stdio.h>
35 #include <string.h>
36 #include <sysexits.h>
37 
38 void
39 usage(void)
40 {
41     fprintf(stderr, "usage: chkgrp [groupfile]\n");
42     exit(EX_USAGE);
43 }
44 
45 int
46 main(int argc, char *argv[])
47 {
48     size_t len;
49     int n = 0, i, k, e = 0;
50     char *gfn, *line, *f[4], *p;
51     FILE *gf;
52 
53     /* check arguments */
54     switch (argc) {
55     case 1:
56 	gfn = "/etc/group";
57 	break;
58     case 2:
59 	gfn = argv[1];
60 	break;
61     default:
62 	gfn = NULL; /* silence compiler */
63 	usage();
64     }
65 
66     /* open group file */
67     if ((gf = fopen(gfn, "r")) == NULL)
68 	err(EX_IOERR, "%s", gfn); /* XXX - is IO_ERR the correct exit code? */
69 
70     /* check line by line */
71     while (++n) {
72 	if ((line = fgetln(gf, &len)) == NULL)
73 	    break;
74 	while (len && isspace(line[len-1]))
75 	    len--;
76 
77 	/* ignore blank lines and comments */
78 	for (p = line; p < (line + len); p++)
79 	    if (!isspace(*p)) break;
80 	if (!len || (*p == '#')) {
81 #if 0
82 	    /* entry is correct, so print it */
83 	    printf("%*.*s\n", len, len, line);
84 #endif
85 	    continue;
86 	}
87 
88 	/*
89 	 * A correct group entry has four colon-separated fields, the third
90 	 * of which must be entirely numeric and the fourth of which may
91 	 * be empty.
92 	 */
93 	for (i = k = 0; k < 4; k++) {
94 	    for (f[k] = line+i; (i < len) && (line[i] != ':'); i++)
95 		/* nothing */ ;
96 	    if ((k < 3) && (line[i] != ':'))
97 		break;
98 	    line[i++] = 0;
99 	}
100 	if (k < 4) {
101 	    warnx("%s: line %d: missing field(s)", gfn, n);
102 	    e++;
103 	    continue;
104 	}
105 
106 	/* check if fourth field ended with a colon */
107 	if (i < len) {
108 	    warnx("%s: line %d: too many fields", gfn, n);
109 	    e++;
110 	    continue;
111 	}
112 
113 	/* check that none of the fields contain whitespace */
114 	for (k = 0; k < 4; k++)
115 	    if (strcspn(f[k], " \t") != strlen(f[k]))
116 		warnx("%s: line %d: field %d contains whitespace",
117 		      gfn, n, k+1);
118 
119 	/* check that the GID is numeric */
120 	if (strspn(f[2], "0123456789") != strlen(f[2])) {
121 	    warnx("%s: line %d: GID is not numeric", gfn, n);
122 	    e++;
123 	    continue;
124 	}
125 
126 #if 0
127 	/* entry is correct, so print it */
128 	printf("%s:%s:%s:%s\n", f[0], f[1], f[2], f[3]);
129 #endif
130     }
131 
132     /* check what broke the loop */
133     if (ferror(gf))
134 	err(EX_IOERR, "%s: line %d", gfn, n);
135 
136     /* done */
137     fclose(gf);
138     exit(e ? EX_DATAERR : EX_OK);
139 }
140