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