1 /* $NetBSD: conf.c,v 1.12 2007/07/02 16:33:05 pooka 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 donated to Berkeley by 8 * Jan-Simon Pendry. 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 * from: Id: conf.c,v 1.2 1992/05/27 07:09:27 jsp Exp 35 * @(#)conf.c 8.2 (Berkeley) 3/27/94 36 */ 37 38 #include <sys/cdefs.h> 39 #ifndef lint 40 __RCSID("$NetBSD: conf.c,v 1.12 2007/07/02 16:33:05 pooka Exp $"); 41 #endif /* not lint */ 42 43 #include <sys/types.h> 44 #include <sys/param.h> 45 #include <sys/syslog.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <unistd.h> 49 #include <string.h> 50 #include <errno.h> 51 #include <limits.h> 52 #include <regex.h> 53 54 #include "portald.h" 55 56 #define ALLOC(ty) (xmalloc(sizeof(ty))) 57 58 typedef struct path path; 59 struct path { 60 qelem p_q; /* 2-way linked list */ 61 int p_lno; /* Line number of this record */ 62 char *p_args; /* copy of arg string (malloc) */ 63 char *p_key; /* Pathname to match (also p_argv[0]) */ 64 regex_t p_re; /* RE to match against pathname (malloc) */ 65 int p_use_re; /* true if entry is RE */ 66 int p_argc; /* number of elements in arg string */ 67 char **p_argv; /* argv[] pointers into arg string (malloc) */ 68 }; 69 70 static void ins_que(qelem *, qelem *); 71 static path *palloc(char *, int, const char *); 72 static void pfree(path *); 73 static int pinsert(path *, qelem *); 74 static void preplace(qelem *, qelem *); 75 static void readfp(qelem *, FILE *, const char *); 76 static void rem_que(qelem *); 77 static void *xmalloc(size_t); 78 79 /* 80 * Add an element to a 2-way list, 81 * just after (pred) 82 */ 83 static void 84 ins_que(qelem *elem, qelem *pred) 85 { 86 qelem *p = pred->q_forw; 87 elem->q_back = pred; 88 elem->q_forw = p; 89 pred->q_forw = elem; 90 p->q_back = elem; 91 } 92 93 /* 94 * Remove an element from a 2-way list 95 */ 96 static void 97 rem_que(qelem *elem) 98 { 99 qelem *p = elem->q_forw; 100 qelem *p2 = elem->q_back; 101 p2->q_forw = p; 102 p->q_back = p2; 103 } 104 105 /* 106 * Error checking malloc 107 */ 108 static void * 109 xmalloc(size_t siz) 110 { 111 void *p = malloc(siz); 112 if (p) 113 return (p); 114 syslog(LOG_ERR, "malloc: failed to get %lu bytes", (u_long)siz); 115 exit(1); 116 } 117 118 /* 119 * Insert the path in the list. 120 * If there is already an element with the same key then 121 * the *second* one is ignored (return 0). If the key is 122 * not found then the path is added to the end of the list 123 * and 1 is returned. 124 */ 125 static int 126 pinsert(path *p0, qelem *q0) 127 { 128 qelem *q; 129 130 if (p0->p_argc == 0) 131 return (0); 132 133 for (q = q0->q_forw; q != q0; q = q->q_forw) { 134 path *p = (path *) q; 135 if (strcmp(p->p_key, p0->p_key) == 0) 136 return (0); 137 } 138 ins_que(&p0->p_q, q0->q_back); 139 return (1); 140 141 } 142 143 static path * 144 palloc(char *cline, int lno, const char *conf_file) 145 { 146 int c, errcode; 147 char *s; 148 char *key; 149 path *p; 150 char **ap; 151 152 /* 153 * Implement comment chars 154 */ 155 s = strchr(cline, '#'); 156 if (s) 157 *s = 0; 158 159 /* 160 * Do a pass through the string to count the number 161 * of arguments 162 */ 163 c = 0; 164 key = strdup(cline); 165 for (s = key; s != NULL; ) { 166 char *val; 167 while ((val = strsep(&s, " \t\n")) != NULL && *val == '\0') 168 ; 169 if (val) 170 c++; 171 } 172 c++; 173 free(key); 174 175 if (c <= 1) 176 return (0); 177 178 /* 179 * Now do another pass and generate a new path structure 180 */ 181 p = ALLOC(path); 182 p->p_argc = 0; 183 p->p_argv = xmalloc(c * sizeof(char *)); 184 p->p_args = strdup(cline); 185 ap = p->p_argv; 186 for (s = p->p_args; s != NULL; ) { 187 char *val; 188 while ((val = strsep(&s, " \t\n")) != NULL && *val == '\0') 189 ; 190 if (val) { 191 *ap++ = val; 192 p->p_argc++; 193 } 194 } 195 *ap = 0; 196 197 #ifdef DEBUG 198 for (c = 0; c < p->p_argc; c++) 199 printf("%sv[%d] = %s\n", c?"\t":"", c, p->p_argv[c]); 200 #endif 201 202 p->p_key = p->p_argv[0]; 203 p->p_use_re = 0; 204 if (strpbrk(p->p_key, RE_CHARS)) { 205 errcode = regcomp(&p->p_re, p->p_key, REG_EXTENDED|REG_NOSUB); 206 if (errcode == 0) 207 p->p_use_re = 1; 208 else { 209 char buf[200]; 210 regerror(errcode, &p->p_re, buf, sizeof(buf)); 211 212 syslog(LOG_WARNING, "%s, line %d: regcomp \"%s\": %s", 213 conf_file, p->p_lno, p->p_key, buf); 214 } 215 } 216 p->p_lno = lno; 217 218 return (p); 219 } 220 221 /* 222 * Free a path structure 223 */ 224 static void 225 pfree(path *p) 226 { 227 free(p->p_args); 228 free((char *) p->p_argv); 229 if (p->p_use_re) 230 regfree(&p->p_re); 231 free((char *) p); 232 } 233 234 /* 235 * Discard all currently held path structures on q0. 236 * and add all the ones on xq. 237 */ 238 static void 239 preplace(qelem *q0, qelem *xq) 240 { 241 /* 242 * While the list is not empty, 243 * take the first element off the list 244 * and free it. 245 */ 246 while (q0->q_forw != q0) { 247 qelem *q = q0->q_forw; 248 rem_que(q); 249 pfree((path *) q); 250 } 251 while (xq->q_forw != xq) { 252 qelem *q = xq->q_forw; 253 rem_que(q); 254 ins_que(q, q0); 255 } 256 } 257 258 /* 259 * Read the lines from the configuration file and 260 * add them to the list of paths. 261 */ 262 static void 263 readfp(qelem *q0, FILE *fp, const char *conf_file) 264 { 265 char cline[LINE_MAX]; 266 int nread = 0; 267 qelem q; 268 269 /* 270 * Make a new empty list. 271 */ 272 q.q_forw = q.q_back = &q; 273 274 /* 275 * Read the lines from the configuration file. 276 */ 277 while (fgets(cline, sizeof(cline), fp)) { 278 path *p = palloc(cline, nread+1, conf_file); 279 if (p && !pinsert(p, &q)) 280 pfree(p); 281 nread++; 282 } 283 284 /* 285 * If some records were read, then throw 286 * away the old list and replace with the 287 * new one. 288 */ 289 if (nread) 290 preplace(q0, &q); 291 } 292 293 /* 294 * Read the configuration file (conf) and replace 295 * the existing path list with the new version. 296 * If the file is not readable, then no changes take place 297 */ 298 int 299 conf_read(qelem *q, const char *conf) 300 { 301 FILE *fp = fopen(conf, "r"); 302 int sverrno; 303 if (fp) { 304 readfp(q, fp, conf); 305 (void) fclose(fp); 306 return 0; 307 } else { 308 sverrno = errno; 309 syslog(LOG_WARNING, "open config file \"%s\": %m", conf); 310 errno = sverrno; 311 return -1; 312 } 313 } 314 315 316 char ** 317 conf_match(qelem *q0, char *key) 318 { 319 qelem *q; 320 321 for (q = q0->q_forw; q != q0; q = q->q_forw) { 322 path *p = (path *) q; 323 if (p->p_use_re) { 324 if (regexec(&p->p_re, key, 0, NULL, 0) == 0) 325 return (p->p_argv+1); 326 } else { 327 if (strncmp(p->p_key, key, strlen(p->p_key)) == 0) 328 return (p->p_argv+1); 329 } 330 } 331 332 return (0); 333 } 334