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