1 /*- 2 * Copyright (c) 1998 Dag-Erling Coïdan Smørgrav 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 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <err.h> 33 #include <errno.h> 34 #include <ctype.h> 35 #include <limits.h> 36 #include <stdint.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <unistd.h> 41 #include <sysexits.h> 42 43 static void __dead2 44 usage(void) 45 { 46 47 fprintf(stderr, "usage: chkgrp [-q] [groupfile]\n"); 48 exit(EX_USAGE); 49 } 50 51 int 52 main(int argc, char *argv[]) 53 { 54 FILE *gf; 55 unsigned long gid; 56 unsigned int i; 57 size_t len; 58 int opt, quiet; 59 int n = 0, k, e = 0; 60 const char *cp, *f[4], *gfn, *p; 61 char *line; 62 63 quiet = 0; 64 while ((opt = getopt(argc, argv, "q")) != -1) { 65 switch (opt) { 66 case 'q': 67 quiet = 1; 68 break; 69 default: 70 usage(); 71 } 72 } 73 74 argc -= optind; 75 argv += optind; 76 77 if (argc == 0) 78 gfn = "/etc/group"; 79 else if (argc == 1) 80 gfn = argv[0]; 81 else 82 usage(); 83 84 /* open group file */ 85 if ((gf = fopen(gfn, "r")) == NULL) 86 err(EX_NOINPUT, "%s", gfn); 87 88 /* check line by line */ 89 while (++n) { 90 if ((line = fgetln(gf, &len)) == NULL) 91 break; 92 if (len > 0 && line[len - 1] != '\n') { 93 warnx("%s: line %d: no newline character", gfn, n); 94 e = 1; 95 } 96 while (len && isspace(line[len-1])) 97 len--; 98 99 /* ignore blank lines and comments */ 100 for (p = line; p < line + len; p++) 101 if (!isspace(*p)) break; 102 if (!len || *p == '#') 103 continue; 104 105 /* 106 * Hack: special case for + line 107 */ 108 if (strncmp(line, "+:::", len) == 0) 109 continue; 110 111 /* 112 * A correct group entry has four colon-separated fields, 113 * the third of which must be entirely numeric and the 114 * fourth of which may be empty. 115 */ 116 for (i = k = 0; k < 4; k++) { 117 for (f[k] = line + i; i < len && line[i] != ':'; i++) 118 /* nothing */ ; 119 if (k < 3 && line[i] != ':') 120 break; 121 line[i++] = 0; 122 } 123 124 if (k < 4) { 125 warnx("%s: line %d: missing field(s)", gfn, n); 126 while (k < 4) 127 f[k++] = ""; 128 e = 1; 129 } 130 131 for (cp = f[0] ; *cp ; cp++) { 132 if (!isalnum(*cp) && *cp != '.' && *cp != '_' && 133 *cp != '-' && (cp > f[0] || *cp != '+')) { 134 warnx("%s: line %d: '%c' invalid character", 135 gfn, n, *cp); 136 e = 1; 137 } 138 } 139 140 for (cp = f[3] ; *cp ; cp++) { 141 if (!isalnum(*cp) && *cp != '.' && *cp != '_' && 142 *cp != '-' && *cp != ',') { 143 warnx("%s: line %d: '%c' invalid character", 144 gfn, n, *cp); 145 e = 1; 146 } 147 } 148 149 /* check if fourth field ended with a colon */ 150 if (i < len) { 151 warnx("%s: line %d: too many fields", gfn, n); 152 e = 1; 153 } 154 155 /* check that none of the fields contain whitespace */ 156 for (k = 0; k < 4; k++) { 157 if (strcspn(f[k], " \t") != strlen(f[k])) { 158 warnx("%s: line %d: field %d contains whitespace", 159 gfn, n, k+1); 160 e = 1; 161 } 162 } 163 164 /* check that the GID is numeric */ 165 if (strspn(f[2], "0123456789") != strlen(f[2])) { 166 warnx("%s: line %d: group id is not numeric", gfn, n); 167 e = 1; 168 } 169 170 /* check the range of the group id */ 171 errno = 0; 172 gid = strtoul(f[2], NULL, 10); 173 if (errno != 0) { 174 warnx("%s: line %d: strtoul failed", gfn, n); 175 } else if (gid > GID_MAX) { 176 warnx("%s: line %d: group id is too large (%ju > %ju)", 177 gfn, n, (uintmax_t)gid, (uintmax_t)GID_MAX); 178 e = 1; 179 } 180 } 181 182 /* check what broke the loop */ 183 if (ferror(gf)) 184 err(EX_IOERR, "%s: line %d", gfn, n); 185 186 /* done */ 187 fclose(gf); 188 if (e == 0 && quiet == 0) 189 printf("%s is fine\n", gfn); 190 exit(e ? EX_DATAERR : EX_OK); 191 } 192