1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1998 Dag-Erling 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 #include <err.h> 33 #include <errno.h> 34 #include <ctype.h> 35 #include <inttypes.h> 36 #include <limits.h> 37 #include <stdint.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <unistd.h> 42 #include <sysexits.h> 43 44 static void __dead2 45 usage(void) 46 { 47 48 fprintf(stderr, "usage: chkgrp [-q] [groupfile]\n"); 49 exit(EX_USAGE); 50 } 51 52 int 53 main(int argc, char *argv[]) 54 { 55 FILE *gf; 56 unsigned long gid; 57 unsigned int i; 58 size_t len; 59 int opt, quiet; 60 int n = 0, k, e = 0; 61 const char *cp, *f[4], *gfn, *p; 62 char *line; 63 64 quiet = 0; 65 while ((opt = getopt(argc, argv, "q")) != -1) { 66 switch (opt) { 67 case 'q': 68 quiet = 1; 69 break; 70 default: 71 usage(); 72 } 73 } 74 75 argc -= optind; 76 argv += optind; 77 78 if (argc == 0) 79 gfn = "/etc/group"; 80 else if (argc == 1) 81 gfn = argv[0]; 82 else 83 usage(); 84 85 /* open group file */ 86 if ((gf = fopen(gfn, "r")) == NULL) 87 err(EX_NOINPUT, "%s", gfn); 88 89 /* check line by line */ 90 while (++n) { 91 if ((line = fgetln(gf, &len)) == NULL) 92 break; 93 if (len > 0 && line[len - 1] != '\n') { 94 warnx("%s: line %d: no newline character", gfn, n); 95 e = 1; 96 } 97 while (len && isspace(line[len-1])) 98 len--; 99 100 /* ignore blank lines and comments */ 101 for (p = line; p < line + len; p++) 102 if (!isspace(*p)) break; 103 if (!len || *p == '#') 104 continue; 105 106 /* 107 * Hack: special case for + line 108 */ 109 if (strncmp(line, "+:::", len) == 0 || 110 strncmp(line, "+:*::", len) == 0) 111 continue; 112 113 /* 114 * A correct group entry has four colon-separated fields, 115 * the third of which must be entirely numeric and the 116 * fourth of which may be empty. 117 */ 118 for (i = k = 0; k < 4; k++) { 119 for (f[k] = line + i; i < len && line[i] != ':'; i++) 120 /* nothing */ ; 121 if (k < 3 && line[i] != ':') 122 break; 123 line[i++] = 0; 124 } 125 126 if (k < 4) { 127 warnx("%s: line %d: missing field(s)", gfn, n); 128 while (k < 4) 129 f[k++] = ""; 130 e = 1; 131 } 132 133 for (cp = f[0] ; *cp ; cp++) { 134 if (!isalnum(*cp) && *cp != '.' && *cp != '_' && 135 *cp != '-' && (cp > f[0] || *cp != '+')) { 136 warnx("%s: line %d: '%c' invalid character", 137 gfn, n, *cp); 138 e = 1; 139 } 140 } 141 142 for (cp = f[3] ; *cp ; cp++) { 143 if (!isalnum(*cp) && *cp != '.' && *cp != '_' && 144 *cp != '-' && *cp != ',') { 145 warnx("%s: line %d: '%c' invalid character", 146 gfn, n, *cp); 147 e = 1; 148 } 149 } 150 151 /* check if fourth field ended with a colon */ 152 if (i < len) { 153 warnx("%s: line %d: too many fields", gfn, n); 154 e = 1; 155 } 156 157 /* check that none of the fields contain whitespace */ 158 for (k = 0; k < 4; k++) { 159 if (strcspn(f[k], " \t") != strlen(f[k])) { 160 warnx("%s: line %d: field %d contains whitespace", 161 gfn, n, k+1); 162 e = 1; 163 } 164 } 165 166 /* check that the GID is numeric */ 167 if (strspn(f[2], "0123456789") != strlen(f[2])) { 168 warnx("%s: line %d: group id is not numeric", gfn, n); 169 e = 1; 170 } 171 172 /* check the range of the group id */ 173 errno = 0; 174 gid = strtoul(f[2], NULL, 10); 175 if (errno != 0) { 176 warnx("%s: line %d: strtoul failed", gfn, n); 177 } else if (gid > GID_MAX) { 178 warnx("%s: line %d: group id is too large (%ju > %ju)", 179 gfn, n, (uintmax_t)gid, (uintmax_t)GID_MAX); 180 e = 1; 181 } 182 } 183 184 /* check what broke the loop */ 185 if (ferror(gf)) 186 err(EX_IOERR, "%s: line %d", gfn, n); 187 188 /* done */ 189 fclose(gf); 190 if (e == 0 && quiet == 0) 191 printf("%s is fine\n", gfn); 192 exit(e ? EX_DATAERR : EX_OK); 193 } 194