getgrent.c revision 1.7
1 /* $NetBSD: getgrent.c,v 1.7 2003/08/07 09:27:57 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Portions Copyright (c) 1994, Jason Downs. All Rights Reserved. 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 3. All advertising materials mentioning features or use of this software 44 * must display the following acknowledgement: 45 * This product includes software developed by the University of 46 * California, Berkeley and its contributors. 47 * 4. Neither the name of the University nor the names of its contributors 48 * may be used to endorse or promote products derived from this software 49 * without specific prior written permission. 50 * 51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 61 * SUCH DAMAGE. 62 */ 63 64 /* 65 * Copied from: lib/libc/gen/getgrent.c 66 * NetBSD: getgrent.c,v 1.46 2003/02/17 00:11:54 simonb Exp 67 * and then gutted, leaving only /etc/group support. 68 */ 69 70 #include <sys/cdefs.h> 71 72 #ifdef __weak_alias 73 #define endgrent _endgrent 74 #define getgrent _getgrent 75 #define getgrgid _getgrgid 76 #define getgrnam _getgrnam 77 #define setgrent _setgrent 78 #define setgroupent _setgroupent 79 80 __weak_alias(endgrent,_endgrent) 81 __weak_alias(getgrent,_getgrent) 82 __weak_alias(getgrgid,_getgrgid) 83 __weak_alias(getgrnam,_getgrnam) 84 __weak_alias(setgrent,_setgrent) 85 __weak_alias(setgroupent,_setgroupent) 86 #endif 87 88 #include <sys/types.h> 89 90 #include <grp.h> 91 #include <limits.h> 92 #include <stdio.h> 93 #include <stdlib.h> 94 #include <string.h> 95 96 struct group *_getgrent_user(const char *); 97 98 static FILE *_gr_fp; 99 static struct group _gr_group; 100 static int _gr_stayopen; 101 static int _gr_filesdone; 102 103 static int grscan(int, gid_t, const char *, const char *); 104 static int grstart(void); 105 static int grmatchline(int, gid_t, const char *, const char *); 106 107 #define MAXGRP 200 108 #define MAXLINELENGTH 1024 109 110 static __aconst char *members[MAXGRP]; 111 static char grline[MAXLINELENGTH]; 112 113 struct group * 114 getgrent(void) 115 { 116 117 if ((!_gr_fp && !grstart()) || !grscan(0, 0, NULL, NULL)) 118 return (NULL); 119 return &_gr_group; 120 } 121 122 /* 123 * _getgrent_user() is designed only to be called by getgrouplist(3) and 124 * hence makes no guarantees about filling the entire structure that it 125 * returns. It may only fill in the group name and gid fields. 126 */ 127 128 struct group * 129 _getgrent_user(const char *user) 130 { 131 132 if ((!_gr_fp && !grstart()) || !grscan(0, 0, NULL, user)) 133 return (NULL); 134 return &_gr_group; 135 } 136 137 struct group * 138 getgrnam(const char *name) 139 { 140 int rval; 141 142 if (!grstart()) 143 return NULL; 144 rval = grscan(1, 0, name, NULL); 145 if (!_gr_stayopen) 146 endgrent(); 147 return (rval) ? &_gr_group : NULL; 148 } 149 150 struct group * 151 getgrgid(gid_t gid) 152 { 153 int rval; 154 155 if (!grstart()) 156 return NULL; 157 rval = grscan(1, gid, NULL, NULL); 158 if (!_gr_stayopen) 159 endgrent(); 160 return (rval) ? &_gr_group : NULL; 161 } 162 163 static int 164 grstart(void) 165 { 166 167 _gr_filesdone = 0; 168 if (_gr_fp) { 169 rewind(_gr_fp); 170 return 1; 171 } 172 return (_gr_fp = fopen(_PATH_GROUP, "r")) ? 1 : 0; 173 } 174 175 void 176 setgrent(void) 177 { 178 179 (void) setgroupent(0); 180 } 181 182 int 183 setgroupent(int stayopen) 184 { 185 186 if (!grstart()) 187 return 0; 188 _gr_stayopen = stayopen; 189 return 1; 190 } 191 192 void 193 endgrent(void) 194 { 195 196 _gr_filesdone = 0; 197 if (_gr_fp) { 198 (void)fclose(_gr_fp); 199 _gr_fp = NULL; 200 } 201 } 202 203 static int 204 grscan(int search, gid_t gid, const char *name, const char *user) 205 { 206 207 if (_gr_filesdone) 208 return 0; 209 for (;;) { 210 if (!fgets(grline, sizeof(grline), _gr_fp)) { 211 if (!search) 212 _gr_filesdone = 1; 213 return 0; 214 } 215 /* skip lines that are too big */ 216 if (!strchr(grline, '\n')) { 217 int ch; 218 219 while ((ch = getc(_gr_fp)) != '\n' && ch != EOF) 220 ; 221 continue; 222 } 223 if (grmatchline(search, gid, name, user)) 224 return 1; 225 } 226 /* NOTREACHED */ 227 } 228 229 static int 230 grmatchline(int search, gid_t gid, const char *name, const char *user) 231 { 232 unsigned long id; 233 __aconst char **m; 234 char *cp, *bp, *ep; 235 236 /* name may be NULL if search is nonzero */ 237 238 bp = grline; 239 _gr_group.gr_name = strsep(&bp, ":\n"); 240 if (search && name && strcmp(_gr_group.gr_name, name)) 241 return 0; 242 _gr_group.gr_passwd = strsep(&bp, ":\n"); 243 if (!(cp = strsep(&bp, ":\n"))) 244 return 0; 245 id = strtoul(cp, &ep, 10); 246 if (id > GID_MAX || *ep != '\0') 247 return 0; 248 _gr_group.gr_gid = (gid_t)id; 249 if (search && name == NULL && _gr_group.gr_gid != gid) 250 return 0; 251 cp = NULL; 252 if (bp == NULL) 253 return 0; 254 for (_gr_group.gr_mem = m = members;; bp++) { 255 if (m == &members[MAXGRP - 1]) 256 break; 257 if (*bp == ',') { 258 if (cp) { 259 *bp = '\0'; 260 *m++ = cp; 261 cp = NULL; 262 } 263 } else if (*bp == '\0' || *bp == '\n' || *bp == ' ') { 264 if (cp) { 265 *bp = '\0'; 266 *m++ = cp; 267 } 268 break; 269 } else if (cp == NULL) 270 cp = bp; 271 } 272 *m = NULL; 273 if (user) { 274 for (m = members; *m; m++) 275 if (!strcmp(user, *m)) 276 return 1; 277 return 0; 278 } 279 return 1; 280 } 281
Indexes created Wed Sep 24 02:09:48 GMT 2025