1 /* $NetBSD: parse_netgroup.c,v 1.6 2003/08/07 11:25:51 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Rick Macklem at The University of Guelph. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 __RCSID("$NetBSD: parse_netgroup.c,v 1.6 2003/08/07 11:25:51 agc Exp $"); 39 #endif 40 41 /* 42 * This is a specially hacked-up version of getnetgrent.c used to parse 43 * data from the stored hash table of netgroup info rather than from a 44 * file. It's used mainly for the parse_netgroup() function. All the YP 45 * stuff and file support has been stripped out since it isn't needed. 46 */ 47 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <unistd.h> 52 53 #include "hash.h" 54 55 /* 56 * Static Variables and functions used by rng_setnetgrent(), rng_getnetgrent() 57 * and rng_endnetgrent(). 58 * 59 * There are two linked lists: 60 * - linelist is just used by setnetgrent() to parse the net group file via. 61 * parse_netgrp() 62 * - netgrp is the list of entries for the current netgroup 63 */ 64 struct linelist { 65 struct linelist *l_next; /* Chain ptr. */ 66 int l_parsed; /* Flag for cycles */ 67 char *l_groupname; /* Name of netgroup */ 68 char *l_line; /* Netgroup entrie(s) to be parsed */ 69 }; 70 71 struct netgrp { 72 struct netgrp *ng_next; /* Chain ptr */ 73 char *ng_str[3]; /* Field pointers, see below */ 74 }; 75 #define NG_HOST 0 /* Host name */ 76 #define NG_USER 1 /* User name */ 77 #define NG_DOM 2 /* and Domain name */ 78 79 static struct linelist *linehead = (struct linelist *)0; 80 static struct netgrp *nextgrp = (struct netgrp *)0; 81 static struct { 82 struct netgrp *gr; 83 char *grname; 84 } grouphead = { 85 (struct netgrp *)0, 86 (char *)0, 87 }; 88 89 extern struct group_entry *gtable[]; 90 91 static int parse_netgrp(const char *); 92 static struct linelist *read_for_group(const char *); 93 94 95 /* 96 * rng_setnetgrent() 97 * Parse the netgroup file looking for the netgroup and build the list 98 * of netgrp structures. Let parse_netgrp() and read_for_group() do 99 * most of the work. 100 */ 101 void 102 rng_setnetgrent(const char *group) 103 { 104 /* Sanity check */ 105 106 if (group == NULL || !strlen(group)) 107 return; 108 109 if (grouphead.gr == (struct netgrp *)0 || 110 strcmp(group, grouphead.grname)) { 111 rng_endnetgrent(); 112 if (parse_netgrp(group)) 113 rng_endnetgrent(); 114 else 115 grouphead.grname = strdup(group); 116 } 117 nextgrp = grouphead.gr; 118 } 119 120 /* 121 * Get the next netgroup off the list. 122 */ 123 int 124 rng_getnetgrent(char **hostp, char **userp, char **domp) 125 { 126 if (nextgrp) { 127 *hostp = nextgrp->ng_str[NG_HOST]; 128 *userp = nextgrp->ng_str[NG_USER]; 129 *domp = nextgrp->ng_str[NG_DOM]; 130 nextgrp = nextgrp->ng_next; 131 return (1); 132 } 133 return (0); 134 } 135 136 /* 137 * rng_endnetgrent() - cleanup 138 */ 139 void 140 rng_endnetgrent(void) 141 { 142 struct linelist *lp, *olp; 143 struct netgrp *gp, *ogp; 144 145 lp = linehead; 146 while (lp) { 147 olp = lp; 148 lp = lp->l_next; 149 free(olp->l_groupname); 150 free(olp->l_line); 151 free((char *)olp); 152 } 153 linehead = (struct linelist *)0; 154 if (grouphead.grname) { 155 free(grouphead.grname); 156 grouphead.grname = (char *)0; 157 } 158 gp = grouphead.gr; 159 while (gp) { 160 ogp = gp; 161 gp = gp->ng_next; 162 if (ogp->ng_str[NG_HOST]) 163 free(ogp->ng_str[NG_HOST]); 164 if (ogp->ng_str[NG_USER]) 165 free(ogp->ng_str[NG_USER]); 166 if (ogp->ng_str[NG_DOM]) 167 free(ogp->ng_str[NG_DOM]); 168 free((char *)ogp); 169 } 170 grouphead.gr = (struct netgrp *)0; 171 } 172 173 /* 174 * Parse the netgroup file setting up the linked lists. 175 */ 176 static int 177 parse_netgrp(const char *group) 178 { 179 char *spos, *epos; 180 int len, strpos; 181 #ifdef DEBUG 182 int fields; 183 #endif 184 char *pos, *gpos; 185 struct netgrp *grp; 186 struct linelist *lp = linehead; 187 188 /* 189 * First, see if the line has already been read in. 190 */ 191 while (lp) { 192 if (!strcmp(group, lp->l_groupname)) 193 break; 194 lp = lp->l_next; 195 } 196 if (lp == (struct linelist *)0 && 197 (lp = read_for_group(group)) == (struct linelist *)0) 198 return (1); 199 if (lp->l_parsed) { 200 #ifdef DEBUG 201 /* 202 * This error message is largely superflous since the 203 * code handles the error condition successfully, and 204 * spewing it out from inside libc can actually hose 205 * certain programs. 206 */ 207 warnx("Cycle in netgroup %s", lp->l_groupname); 208 #endif 209 return (1); 210 } else 211 lp->l_parsed = 1; 212 pos = lp->l_line; 213 /* Watch for null pointer dereferences, dammit! */ 214 while (pos != NULL && *pos != '\0') { 215 if (*pos == '(') { 216 grp = (struct netgrp *)malloc(sizeof (struct netgrp)); 217 memset((char *)grp, 0, sizeof (struct netgrp)); 218 grp->ng_next = grouphead.gr; 219 grouphead.gr = grp; 220 pos++; 221 gpos = strsep(&pos, ")"); 222 #ifdef DEBUG 223 fields = 0; 224 #endif 225 for (strpos = 0; strpos < 3; strpos++) { 226 if ((spos = strsep(&gpos, ","))) { 227 #ifdef DEBUG 228 fields++; 229 #endif 230 while (*spos == ' ' || *spos == '\t') 231 spos++; 232 if ((epos = strpbrk(spos, " \t"))) { 233 *epos = '\0'; 234 len = epos - spos; 235 } else 236 len = strlen(spos); 237 if (len > 0) { 238 grp->ng_str[strpos] = (char *) 239 malloc(len + 1); 240 memmove(grp->ng_str[strpos], 241 spos, len + 1); 242 } 243 } else { 244 /* 245 * All other systems I've tested 246 * return NULL for empty netgroup 247 * fields. It's up to user programs 248 * to handle the NULLs appropriately. 249 */ 250 grp->ng_str[strpos] = NULL; 251 } 252 } 253 #ifdef DEBUG 254 /* 255 * Note: on other platforms, malformed netgroup 256 * entries are not normally flagged. While we 257 * can catch bad entries and report them, we should 258 * stay silent by default for compatibility's sake. 259 */ 260 if (fields < 3) 261 warnx( 262 "Bad entry (%s%s%s%s%s) in netgroup \"%s\"", 263 grp->ng_str[NG_HOST] == NULL ? "" : 264 grp->ng_str[NG_HOST], 265 grp->ng_str[NG_USER] == NULL ? "" : ",", 266 grp->ng_str[NG_USER] == NULL ? "" : 267 grp->ng_str[NG_USER], 268 grp->ng_str[NG_DOM] == NULL ? "" : ",", 269 grp->ng_str[NG_DOM] == NULL ? "" : 270 grp->ng_str[NG_DOM], 271 lp->l_groupname); 272 #endif 273 } else { 274 spos = strsep(&pos, ", \t"); 275 if (parse_netgrp(spos)) 276 continue; 277 } 278 /* Watch for null pointer dereferences, dammit! */ 279 if (pos != NULL) 280 while (*pos == ' ' || *pos == ',' || *pos == '\t') 281 pos++; 282 } 283 return (0); 284 } 285 286 /* 287 * Read the netgroup file and save lines until the line for the netgroup 288 * is found. Return 1 if eof is encountered. 289 */ 290 static struct linelist * 291 read_for_group(const char *group) 292 { 293 char *pos, *spos, *linep = NULL, *olinep = NULL; 294 int len, olen; 295 int cont; 296 struct linelist *lp; 297 char line[LINSIZ + 1]; 298 char *data = NULL; 299 300 data = lookup (gtable, group); 301 snprintf(line, sizeof(line), "%s %s", group, data); 302 pos = (char *)&line; 303 #ifdef CANT_HAPPEN 304 if (*pos == '#') 305 continue; 306 #endif 307 while (*pos == ' ' || *pos == '\t') 308 pos++; 309 spos = pos; 310 while (*pos != ' ' && *pos != '\t' && *pos != '\n' && 311 *pos != '\0') 312 pos++; 313 len = pos - spos; 314 while (*pos == ' ' || *pos == '\t') 315 pos++; 316 if (*pos != '\n' && *pos != '\0') { 317 lp = (struct linelist *)malloc(sizeof (*lp)); 318 lp->l_parsed = 0; 319 lp->l_groupname = (char *)malloc(len + 1); 320 memmove(lp->l_groupname, spos, len); 321 *(lp->l_groupname + len) = '\0'; 322 len = strlen(pos); 323 olen = 0; 324 /* 325 * Loop around handling line continuations. 326 */ 327 do { 328 if (*(pos + len - 1) == '\n') 329 len--; 330 if (*(pos + len - 1) == '\\') { 331 len--; 332 cont = 1; 333 } else 334 cont = 0; 335 if (len > 0) { 336 linep = (char *)malloc(olen + len + 1); 337 if (olen > 0) { 338 memmove(linep, olinep, olen); 339 free(olinep); 340 } 341 memmove(linep + olen, pos, len); 342 olen += len; 343 *(linep + olen) = '\0'; 344 olinep = linep; 345 } 346 #ifdef CANT_HAPPEN 347 if (cont) { 348 if (fgets(line, LINSIZ, netf)) { 349 pos = line; 350 len = strlen(pos); 351 } else 352 cont = 0; 353 } 354 #endif 355 } while (cont); 356 lp->l_line = linep; 357 lp->l_next = linehead; 358 linehead = lp; 359 #ifdef CANT_HAPPEN 360 /* 361 * If this is the one we wanted, we are done. 362 */ 363 if (!strcmp(lp->l_groupname, group)) 364 #endif 365 return (lp); 366 } 367 return ((struct linelist *)0); 368 } 369
Indexes created Sat Sep 20 22:09:52 GMT 2025