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 * $FreeBSD: src/usr.sbin/chkgrp/chkgrp.c,v 1.3.2.2 2001/07/12 22:57:35 mjacob Exp $ 29 * $DragonFly: src/usr.sbin/chkgrp/chkgrp.c,v 1.6 2005/08/25 17:09:32 liamfoy Exp $ 30 */ 31 #include <sys/types.h> 32 33 #include <ctype.h> 34 #include <err.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #include <sysexits.h> 39 40 #define DEFAULTGFILE "/etc/group" 41 42 static void usage(void); 43 static char empty[] = { 0 }; 44 45 static void 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 size_t len; 56 int n = 0, i, k, e = 0; 57 char *line, *f[4], *p; 58 const char *cp, *gfn; 59 FILE *gf; 60 61 /* check arguments */ 62 switch (argc) { 63 case 1: 64 gfn = DEFAULTGFILE; 65 break; 66 case 2: 67 gfn = argv[1]; 68 break; 69 default: 70 gfn = NULL; /* silence compiler */ 71 usage(); 72 } 73 74 /* open group file */ 75 if ((gf = fopen(gfn, "r")) == NULL) 76 err(EX_IOERR, "%s", gfn); 77 78 /* check line by line */ 79 while (++n) { 80 if ((line = fgetln(gf, &len)) == NULL) 81 break; 82 if (len > 0 && line[len - 1] != '\n') { 83 warnx("%s: line %d: no newline character", gfn, n); 84 e++; 85 } 86 while (len && isspace(line[len - 1])) 87 len--; 88 89 /* ignore blank lines and comments */ 90 for (p = line; p < (line + len); p++) 91 if (!isspace(*p)) 92 break; 93 if (!len || (*p == '#')) { 94 #if 0 95 /* entry is correct, so print it */ 96 printf("%*.*s\n", len, len, line); 97 #endif 98 continue; 99 } 100 /* 101 * A correct group entry has four colon-separated fields, the 102 * third of which must be entirely numeric and the fourth of 103 * which may be empty. We also check for any incorrect characters. 104 */ 105 for (i = k = 0; k < 4; k++) { 106 for (f[k] = line + i; (i < (int)len) && (line[i] != ':'); i++) 107 /* nothing */ ; 108 if ((k < 3) && (line[i] != ':')) 109 break; 110 line[i++] = 0; 111 } 112 113 if (k < 4) { 114 warnx("%s: line %d: missing field(s)", gfn, n); 115 for ( ; k < 4; k++) 116 f[k] = empty; 117 e++; 118 } 119 120 for (cp = f[0] ; *cp ; cp++) { 121 if (!isalnum(*cp) && *cp != '.' && *cp != '_' && *cp != '-' && 122 (cp > f[0] || *cp != '+')) { 123 warnx("%s: line %d: '%c' invalid character", gfn, n, *cp); 124 e++; 125 } 126 } 127 128 for (cp = f[3] ; *cp ; cp++) { 129 if (!isalnum(*cp) && *cp != ',' && *cp != '.' && *cp != '_' && *cp != '-') { 130 warnx("%s: line %d: '%c' invalid character", gfn, n, *cp); 131 e++; 132 } 133 } 134 135 /* check if fourth field ended with a colon */ 136 if (i < (int)len) { 137 warnx("%s: line %d: too many fields", gfn, n); 138 e++; 139 } 140 /* check that none of the fields contain whitespace */ 141 for (k = 0; k < 4; k++) { 142 if (strcspn(f[k], " \t") != strlen(f[k])) { 143 warnx("%s: line %d: field %d contains whitespace", 144 gfn, n, k + 1); 145 e++; 146 } 147 } 148 149 /* check that the GID is numeric */ 150 if (strspn(f[2], "0123456789") != strlen(f[2])) { 151 warnx("%s: line %d: GID is not numeric", gfn, n); 152 e++; 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