1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1998 Dag-Erling Coïdan Smørgrav
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer
12 * in this position and unchanged.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD: stable/12/usr.sbin/chkgrp/chkgrp.c 326276 2017-11-27 15:37:16Z pfg $");
33
34 #include <err.h>
35 #include <errno.h>
36 #include <ctype.h>
37 #include <inttypes.h>
38 #include <limits.h>
39 #include <stdint.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h>
44 #include <sysexits.h>
45
46 static void __dead2
usage(void)47 usage(void)
48 {
49
50 fprintf(stderr, "usage: chkgrp [-q] [groupfile]\n");
51 exit(EX_USAGE);
52 }
53
54 int
main(int argc,char * argv[])55 main(int argc, char *argv[])
56 {
57 FILE *gf;
58 unsigned long gid;
59 unsigned int i;
60 size_t len;
61 int opt, quiet;
62 int n = 0, k, e = 0;
63 const char *cp, *f[4], *gfn, *p;
64 char *line;
65
66 quiet = 0;
67 while ((opt = getopt(argc, argv, "q")) != -1) {
68 switch (opt) {
69 case 'q':
70 quiet = 1;
71 break;
72 default:
73 usage();
74 }
75 }
76
77 argc -= optind;
78 argv += optind;
79
80 if (argc == 0)
81 gfn = "/etc/group";
82 else if (argc == 1)
83 gfn = argv[0];
84 else
85 usage();
86
87 /* open group file */
88 if ((gf = fopen(gfn, "r")) == NULL)
89 err(EX_NOINPUT, "%s", gfn);
90
91 /* check line by line */
92 while (++n) {
93 if ((line = fgetln(gf, &len)) == NULL)
94 break;
95 if (len > 0 && line[len - 1] != '\n') {
96 warnx("%s: line %d: no newline character", gfn, n);
97 e = 1;
98 }
99 while (len && isspace(line[len-1]))
100 len--;
101
102 /* ignore blank lines and comments */
103 for (p = line; p < line + len; p++)
104 if (!isspace(*p)) break;
105 if (!len || *p == '#')
106 continue;
107
108 /*
109 * Hack: special case for + line
110 */
111 if (strncmp(line, "+:::", len) == 0 ||
112 strncmp(line, "+:*::", len) == 0)
113 continue;
114
115 /*
116 * A correct group entry has four colon-separated fields,
117 * the third of which must be entirely numeric and the
118 * fourth of which may be empty.
119 */
120 for (i = k = 0; k < 4; k++) {
121 for (f[k] = line + i; i < len && line[i] != ':'; i++)
122 /* nothing */ ;
123 if (k < 3 && line[i] != ':')
124 break;
125 line[i++] = 0;
126 }
127
128 if (k < 4) {
129 warnx("%s: line %d: missing field(s)", gfn, n);
130 while (k < 4)
131 f[k++] = "";
132 e = 1;
133 }
134
135 for (cp = f[0] ; *cp ; cp++) {
136 if (!isalnum(*cp) && *cp != '.' && *cp != '_' &&
137 *cp != '-' && (cp > f[0] || *cp != '+')) {
138 warnx("%s: line %d: '%c' invalid character",
139 gfn, n, *cp);
140 e = 1;
141 }
142 }
143
144 for (cp = f[3] ; *cp ; cp++) {
145 if (!isalnum(*cp) && *cp != '.' && *cp != '_' &&
146 *cp != '-' && *cp != ',') {
147 warnx("%s: line %d: '%c' invalid character",
148 gfn, n, *cp);
149 e = 1;
150 }
151 }
152
153 /* check if fourth field ended with a colon */
154 if (i < len) {
155 warnx("%s: line %d: too many fields", gfn, n);
156 e = 1;
157 }
158
159 /* check that none of the fields contain whitespace */
160 for (k = 0; k < 4; k++) {
161 if (strcspn(f[k], " \t") != strlen(f[k])) {
162 warnx("%s: line %d: field %d contains whitespace",
163 gfn, n, k+1);
164 e = 1;
165 }
166 }
167
168 /* check that the GID is numeric */
169 if (strspn(f[2], "0123456789") != strlen(f[2])) {
170 warnx("%s: line %d: group id is not numeric", gfn, n);
171 e = 1;
172 }
173
174 /* check the range of the group id */
175 errno = 0;
176 gid = strtoul(f[2], NULL, 10);
177 if (errno != 0) {
178 warnx("%s: line %d: strtoul failed", gfn, n);
179 } else if (gid > GID_MAX) {
180 warnx("%s: line %d: group id is too large (%ju > %ju)",
181 gfn, n, (uintmax_t)gid, (uintmax_t)GID_MAX);
182 e = 1;
183 }
184 }
185
186 /* check what broke the loop */
187 if (ferror(gf))
188 err(EX_IOERR, "%s: line %d", gfn, n);
189
190 /* done */
191 fclose(gf);
192 if (e == 0 && quiet == 0)
193 printf("%s is fine\n", gfn);
194 exit(e ? EX_DATAERR : EX_OK);
195 }
196