1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. 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 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)getgrent.c 8.2 (Berkeley) 3/21/94"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/types.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include <grp.h> 43 44 static FILE *_gr_fp; 45 static struct group _gr_group; 46 static int _gr_stayopen; 47 static int grscan(), start_gr(); 48 #ifdef YP 49 static int _gr_stepping_yp; 50 static int _gr_yp_enabled; 51 static int _getypgroup(struct group *, const char *, const char *); 52 static int _nextypgroup(struct group *); 53 #endif 54 55 #define MAXGRP 200 56 static char *members[MAXGRP]; 57 #define MAXLINELENGTH 1024 58 static char line[MAXLINELENGTH]; 59 60 struct group * 61 getgrent() 62 { 63 if (!_gr_fp && !start_gr()) { 64 return NULL; 65 } 66 67 #ifdef YP 68 if (_gr_stepping_yp) { 69 return (_nextypgroup(&_gr_group) ? &_gr_group : 0); 70 } 71 #endif 72 73 if (!grscan(0, 0, NULL)) 74 return(NULL); 75 #ifdef YP 76 if(_gr_group.gr_name[0] == '+' && _gr_group.gr_name[1]) { 77 _getypgroup(&_gr_group, &_gr_group.gr_name[1], 78 "group.byname"); 79 } else if(_gr_group.gr_name[0] == '+') { 80 return (_nextypgroup(&_gr_group) ? &_gr_group : 0); 81 } 82 #endif 83 return(&_gr_group); 84 } 85 86 struct group * 87 getgrnam(name) 88 const char *name; 89 { 90 int rval; 91 92 if (!start_gr()) 93 return(NULL); 94 rval = grscan(1, 0, name); 95 #ifdef YP 96 if(!rval && _gr_yp_enabled < 0) { 97 rval = _getypgroup(&_gr_group, name, "group.byname"); 98 } 99 #endif 100 if (!_gr_stayopen) 101 endgrent(); 102 return(rval ? &_gr_group : NULL); 103 } 104 105 struct group * 106 #ifdef __STDC__ 107 getgrgid(gid_t gid) 108 #else 109 getgrgid(gid) 110 gid_t gid; 111 #endif 112 { 113 int rval; 114 115 if (!start_gr()) 116 return(NULL); 117 rval = grscan(1, gid, NULL); 118 #ifdef YP 119 if(!rval && _gr_yp_enabled) { 120 char buf[16]; 121 snprintf(buf, sizeof buf, "%d", (unsigned)gid); 122 rval = _getypgroup(&_gr_group, buf, "group.bygid"); 123 } 124 #endif 125 if (!_gr_stayopen) 126 endgrent(); 127 return(rval ? &_gr_group : NULL); 128 } 129 130 static int 131 start_gr() 132 { 133 if (_gr_fp) { 134 rewind(_gr_fp); 135 return(1); 136 } 137 _gr_fp = fopen(_PATH_GROUP, "r"); 138 if(!_gr_fp) return 0; 139 #ifdef YP 140 /* 141 * This is a disgusting hack, used to determine when YP is enabled. 142 * This would be easier if we had a group database to go along with 143 * the password database. 144 */ 145 { 146 char *line; 147 size_t linelen; 148 _gr_yp_enabled = 0; 149 while(line = fgetln(_gr_fp, &linelen)) { 150 if(line[0] == '+') { 151 if(line[1] && !_gr_yp_enabled) { 152 _gr_yp_enabled = 1; 153 } else { 154 _gr_yp_enabled = -1; 155 break; 156 } 157 } 158 } 159 rewind(_gr_fp); 160 } 161 #endif 162 return 1; 163 } 164 165 int 166 setgrent() 167 { 168 return(setgroupent(0)); 169 } 170 171 int 172 setgroupent(stayopen) 173 int stayopen; 174 { 175 if (!start_gr()) 176 return(0); 177 _gr_stayopen = stayopen; 178 #ifdef YP 179 _gr_stepping_yp = 0; 180 #endif 181 return(1); 182 } 183 184 void 185 endgrent() 186 { 187 #ifdef YP 188 _gr_stepping_yp = 0; 189 #endif 190 if (_gr_fp) { 191 (void)fclose(_gr_fp); 192 _gr_fp = NULL; 193 } 194 } 195 196 static int 197 grscan(search, gid, name) 198 register int search, gid; 199 register char *name; 200 { 201 register char *cp, **m; 202 char *bp; 203 char *fgets(), *strsep(), *index(); 204 205 for (;;) { 206 if (!fgets(line, sizeof(line), _gr_fp)) 207 return(0); 208 bp = line; 209 /* skip lines that are too big */ 210 if (!index(line, '\n')) { 211 int ch; 212 213 while ((ch = getc(_gr_fp)) != '\n' && ch != EOF) 214 ; 215 continue; 216 } 217 _gr_group.gr_name = strsep(&bp, ":\n"); 218 if (search && name) { 219 #ifdef YP 220 if(_gr_group.gr_name[0] == '+') { 221 if(strcmp(&_gr_group.gr_name[1], name)) { 222 continue; 223 } 224 return _getypgroup(&_gr_group, name, 225 "group.byname"); 226 } 227 #endif /* YP */ 228 if(strcmp(_gr_group.gr_name, name)) { 229 continue; 230 } 231 } 232 _gr_group.gr_passwd = strsep(&bp, ":\n"); 233 if (!(cp = strsep(&bp, ":\n"))) 234 continue; 235 _gr_group.gr_gid = atoi(cp); 236 if (search && name == NULL && _gr_group.gr_gid != gid) 237 continue; 238 cp = NULL; 239 for (m = _gr_group.gr_mem = members;; bp++) { 240 if (m == &members[MAXGRP - 1]) 241 break; 242 if (*bp == ',') { 243 if (cp) { 244 *bp = '\0'; 245 *m++ = cp; 246 cp = NULL; 247 } 248 } else if (*bp == '\0' || *bp == '\n' || *bp == ' ') { 249 if (cp) { 250 *bp = '\0'; 251 *m++ = cp; 252 } 253 break; 254 } else if (cp == NULL) 255 cp = bp; 256 } 257 *m = NULL; 258 return(1); 259 } 260 /* NOTREACHED */ 261 } 262 263 #ifdef YP 264 265 static void 266 _gr_breakout_yp(struct group *gr, char *result) 267 { 268 char *s, *cp; 269 char **m; 270 271 s = strsep(&result, ":"); /* name */ 272 gr->gr_name = s; 273 274 s = strsep(&result, ":"); /* password */ 275 gr->gr_passwd = s; 276 277 s = strsep(&result, ":"); /* gid */ 278 gr->gr_gid = atoi(s); 279 280 s = result; 281 cp = 0; 282 283 for (m = _gr_group.gr_mem = members; /**/; s++) { 284 if (m == &members[MAXGRP - 1]) { 285 break; 286 } 287 if (*s == ',') { 288 if (cp) { 289 *s = '\0'; 290 *m++ = cp; 291 cp = NULL; 292 } 293 } else if (*s == '\0' || *s == '\n' || *s == ' ') { 294 if (cp) { 295 *s = '\0'; 296 *m++ = cp; 297 } 298 break; 299 } else if (cp == NULL) { 300 cp = s; 301 } 302 } 303 *m = NULL; 304 } 305 306 static char *_gr_yp_domain; 307 308 static int 309 _getypgroup(struct group *gr, const char *name, const char *map) 310 { 311 char *result, *s; 312 static char resultbuf[1024]; 313 int resultlen; 314 315 if(!_gr_yp_domain) { 316 if(yp_get_default_domain(&_gr_yp_domain)) 317 return 0; 318 } 319 320 if(yp_match(_gr_yp_domain, map, name, strlen(name), 321 &result, &resultlen)) 322 return 0; 323 324 s = strchr(result, '\n'); 325 if(s) *s = '\0'; 326 327 if(resultlen >= sizeof resultbuf) return 0; 328 strcpy(resultbuf, result); 329 result = resultbuf; 330 _gr_breakout_yp(gr, resultbuf); 331 332 return 1; 333 } 334 335 336 static int 337 _nextypgroup(struct group *gr) 338 { 339 static char *key; 340 static int keylen; 341 char *lastkey, *result; 342 static char resultbuf[1024]; 343 int resultlen; 344 int rv; 345 346 if(!_gr_yp_domain) { 347 if(yp_get_default_domain(&_gr_yp_domain)) 348 return 0; 349 } 350 351 if(!_gr_stepping_yp) { 352 if(key) free(key); 353 rv = yp_first(_gr_yp_domain, "group.byname", 354 &key, &keylen, &result, &resultlen); 355 if(rv) { 356 return 0; 357 } 358 _gr_stepping_yp = 1; 359 goto unpack; 360 } else { 361 tryagain: 362 lastkey = key; 363 rv = yp_next(_gr_yp_domain, "group.byname", key, keylen, 364 &key, &keylen, &result, &resultlen); 365 free(lastkey); 366 unpack: 367 if(rv) { 368 _gr_stepping_yp = 0; 369 return 0; 370 } 371 372 if(resultlen > sizeof(resultbuf)) { 373 free(result); 374 goto tryagain; 375 } 376 377 strcpy(resultbuf, result); 378 free(result); 379 if(result = strchr(resultbuf, '\n')) *result = '\0'; 380 _gr_breakout_yp(gr, resultbuf); 381 } 382 return 1; 383 } 384 385 #endif /* YP */ 386