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