1 /* $NetBSD: getnetconfig.c,v 1.1 2000/06/02 23:11:11 fvdl Exp $ */ 2 3 /* 4 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for 5 * unrestricted use provided that this legend is included on all tape 6 * media and as a part of the software program in whole or part. Users 7 * may copy or modify Sun RPC without charge, but are not authorized 8 * to license or distribute it to anyone else except as part of a product or 9 * program developed by the user or with the express written consent of 10 * Sun Microsystems, Inc. 11 * 12 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE 13 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR 14 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. 15 * 16 * Sun RPC is provided with no support and without any obligation on the 17 * part of Sun Microsystems, Inc. to assist in its use, correction, 18 * modification or enhancement. 19 * 20 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE 21 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC 22 * OR ANY PART THEREOF. 23 * 24 * In no event will Sun Microsystems, Inc. be liable for any lost revenue 25 * or profits or other special, indirect and consequential damages, even if 26 * Sun has been advised of the possibility of such damages. 27 * 28 * Sun Microsystems, Inc. 29 * 2550 Garcia Avenue 30 * Mountain View, California 94043 31 */ 32 /* 33 #ifndef lint 34 static char sccsid[] = "@(#)getnetconfig.c 1.12 91/12/19 SMI"; 35 #endif 36 */ 37 38 /* 39 * Copyright (c) 1989 by Sun Microsystems, Inc. 40 */ 41 42 #include "namespace.h" 43 #include <sys/cdefs.h> 44 #include <stdio.h> 45 #include <errno.h> 46 #include <netconfig.h> 47 #include <stdlib.h> 48 #include <string.h> 49 50 #ifdef __weak_alias 51 __weak_alias(getnetconfig,_getnetconfig) 52 __weak_alias(setnetconfig,_setnetconfig) 53 __weak_alias(endnetconfig,_endnetconfig) 54 __weak_alias(getnetconfigent,_getnetconfigent) 55 __weak_alias(freenetconfigent,_freenetconfigent) 56 __weak_alias(nc_perror,_nc_perror) 57 __weak_alias(nc_sperror,_nc_sperror) 58 #endif 59 60 /* 61 * The five library routines in this file provide application access to the 62 * system network configuration database, /etc/netconfig. In addition to the 63 * netconfig database and the routines for accessing it, the environment 64 * variable NETPATH and its corresponding routines in getnetpath.c may also be 65 * used to specify the network transport to be used. 66 */ 67 68 69 /* 70 * netconfig errors 71 */ 72 73 #define NC_NONETCONFIG ENOENT 74 #define NC_NOMEM ENOMEM 75 #define NC_NOTINIT EINVAL /* setnetconfig was not called first */ 76 #define NC_BADFILE EBADF /* format for netconfig file is bad */ 77 78 /* 79 * semantics as strings (should be in netconfig.h) 80 */ 81 #define NC_TPI_CLTS_S "tpi_clts" 82 #define NC_TPI_COTS_S "tpi_cots" 83 #define NC_TPI_COTS_ORD_S "tpi_cots_ord" 84 #define NC_TPI_RAW_S "tpi_raw" 85 86 /* 87 * flags as characters (also should be in netconfig.h) 88 */ 89 #define NC_NOFLAG_C '-' 90 #define NC_VISIBLE_C 'v' 91 #define NC_BROADCAST_C 'b' 92 93 /* 94 * Character used to indicate there is no name-to-address lookup library 95 */ 96 #define NC_NOLOOKUP "-" 97 98 static char *_nc_errors[] = { 99 "Netconfig database not found", 100 "Not enough memory", 101 "Not initialized", 102 "Netconfig database has invalid format" 103 }; 104 105 struct netconfig_info { 106 int eof; /* all entries has been read */ 107 int ref; /* # of times setnetconfig() has been called */ 108 struct netconfig_list *head; /* head of the list */ 109 struct netconfig_list *tail; /* last of the list */ 110 }; 111 112 struct netconfig_list { 113 char *linep; /* hold line read from netconfig */ 114 struct netconfig *ncp; 115 struct netconfig_list *next; 116 }; 117 118 struct netconfig_vars { 119 int valid; /* token that indicates a valid netconfig_vars */ 120 int flag; /* first time flag */ 121 struct netconfig_list *nc_configs; /* pointer to the current netconfig entry */ 122 }; 123 124 #define NC_VALID 0xfeed 125 #define NC_STORAGE 0xf00d 126 #define NC_INVALID 0 127 128 129 extern char *_get_next_token __P((char *, char)); /* getnetpath.c */ 130 static int *__nc_error __P((void)); 131 static int parse_ncp __P((char *, struct netconfig *)); 132 static struct netconfig *dup_ncp __P((struct netconfig *)); 133 134 135 static FILE *nc_file; /* for netconfig db */ 136 static struct netconfig_info ni = { 0, 0, NULL, NULL}; 137 138 #define MAXNETCONFIGLINE 1000 139 140 static int * 141 __nc_error() 142 { 143 #ifdef __REENT 144 static thread_key_t nc_key = 0; 145 int *nc_addr = NULL; 146 #endif 147 static int nc_error = 0; 148 149 #ifdef __REENT 150 if (_thr_getspecific(nc_key, (void **) &nc_addr) != 0) { 151 mutex_lock(&nc_lock); 152 if (_thr_keycreate(&rce_key, free) != 0) { 153 mutex_unlock(&nc_lock); 154 return nc_addr; 155 } 156 mutex_unlock(&nc_lock); 157 } 158 if (nc_addr == NULL) { 159 nc_addr = (int *)malloc(sizeof (int)); 160 if (_thr_setspecific(nc_key, (void *) nc_addr) != 0) { 161 if (nc_addr) 162 free(nc_addr); 163 return &nc_error; 164 } 165 *nc_addr = 0; 166 return nc_addr; 167 } 168 return nc_addr; 169 #else 170 return &nc_error; 171 #endif 172 } 173 174 #define nc_error (*(__nc_error())) 175 /* 176 * A call to setnetconfig() establishes a /etc/netconfig "session". A session 177 * "handle" is returned on a successful call. At the start of a session (after 178 * a call to setnetconfig()) searches through the /etc/netconfig database will 179 * proceed from the start of the file. The session handle must be passed to 180 * getnetconfig() to parse the file. Each call to getnetconfig() using the 181 * current handle will process one subsequent entry in /etc/netconfig. 182 * setnetconfig() must be called before the first call to getnetconfig(). 183 * (Handles are used to allow for nested calls to setnetpath()). 184 * 185 * A new session is established with each call to setnetconfig(), with a new 186 * handle being returned on each call. Previously established sessions remain 187 * active until endnetconfig() is called with that session's handle as an 188 * argument. 189 * 190 * setnetconfig() need *not* be called before a call to getnetconfigent(). 191 * setnetconfig() returns a NULL pointer on failure (for example, if 192 * the netconfig database is not present). 193 */ 194 void * 195 setnetconfig() 196 { 197 struct netconfig_vars *nc_vars; 198 199 if ((nc_vars = (struct netconfig_vars *)malloc(sizeof 200 (struct netconfig_vars))) == NULL) { 201 return(NULL); 202 } 203 204 /* 205 * For multiple calls, i.e. nc_file is not NULL, we just return the 206 * handle without reopening the netconfig db. 207 */ 208 ni.ref++; 209 if ((nc_file != NULL) || (nc_file = fopen(NETCONFIG, "r")) != NULL) { 210 nc_vars->valid = NC_VALID; 211 nc_vars->flag = 0; 212 nc_vars->nc_configs = ni.head; 213 return ((void *)nc_vars); 214 } 215 ni.ref--; 216 nc_error = NC_NONETCONFIG; 217 free(nc_vars); 218 return (NULL); 219 } 220 221 222 /* 223 * When first called, getnetconfig() returns a pointer to the first entry in 224 * the netconfig database, formatted as a struct netconfig. On each subsequent 225 * call, getnetconfig() returns a pointer to the next entry in the database. 226 * getnetconfig() can thus be used to search the entire netconfig file. 227 * getnetconfig() returns NULL at end of file. 228 */ 229 230 struct netconfig * 231 getnetconfig(handlep) 232 void *handlep; 233 { 234 struct netconfig_vars *ncp = (struct netconfig_vars *)handlep; 235 char *stringp; /* tmp string pointer */ 236 struct netconfig_list *list; 237 struct netconfig *np; 238 239 /* 240 * Verify that handle is valid 241 */ 242 if (ncp == NULL || nc_file == NULL) { 243 nc_error = NC_NOTINIT; 244 return (NULL); 245 } 246 247 switch (ncp->valid) { 248 case NC_VALID: 249 /* 250 * If entry has already been read into the list, 251 * we return the entry in the linked list. 252 * If this is the first time call, check if there are any entries in 253 * linked list. If no entries, we need to read the netconfig db. 254 * If we have been here and the next entry is there, we just return 255 * it. 256 */ 257 if (ncp->flag == 0) { /* first time */ 258 ncp->flag = 1; 259 ncp->nc_configs = ni.head; 260 if (ncp->nc_configs != NULL) /* entry already exist */ 261 return(ncp->nc_configs->ncp); 262 } 263 else if (ncp->nc_configs != NULL && ncp->nc_configs->next != NULL) { 264 ncp->nc_configs = ncp->nc_configs->next; 265 return(ncp->nc_configs->ncp); 266 } 267 268 /* 269 * If we cannot find the entry in the list and is end of file, 270 * we give up. 271 */ 272 if (ni.eof == 1) return(NULL); 273 break; 274 default: 275 nc_error = NC_NOTINIT; 276 return (NULL); 277 } 278 279 stringp = (char *) malloc(MAXNETCONFIGLINE); 280 if (stringp == NULL) 281 return (NULL); 282 283 #ifdef MEM_CHK 284 if (malloc_verify() == 0) { 285 fprintf(stderr, "memory heap corrupted in getnetconfig\n"); 286 exit(1); 287 } 288 #endif 289 290 /* 291 * Read a line from netconfig file. 292 */ 293 do { 294 if (fgets(stringp, MAXNETCONFIGLINE, nc_file) == NULL) { 295 free(stringp); 296 ni.eof = 1; 297 return (NULL); 298 } 299 } while (*stringp == '#'); 300 301 list = (struct netconfig_list *) malloc(sizeof (struct netconfig_list)); 302 if (list == NULL) { 303 free(stringp); 304 return(NULL); 305 } 306 np = (struct netconfig *) malloc(sizeof (struct netconfig)); 307 if (np == NULL) { 308 free(stringp); 309 free(list); 310 return(NULL); 311 } 312 list->ncp = np; 313 list->next = NULL; 314 list->ncp->nc_lookups = NULL; 315 list->linep = stringp; 316 if (parse_ncp(stringp, list->ncp) == -1) { 317 free(stringp); 318 free(np); 319 free(list); 320 return (NULL); 321 } 322 else { 323 /* 324 * If this is the first entry that's been read, it is the head of 325 * the list. If not, put the entry at the end of the list. 326 * Reposition the current pointer of the handle to the last entry 327 * in the list. 328 */ 329 if (ni.head == NULL) { /* first entry */ 330 ni.head = ni.tail = list; 331 } 332 else { 333 ni.tail->next = list; 334 ni.tail = ni.tail->next; 335 } 336 ncp->nc_configs = ni.tail; 337 return(ni.tail->ncp); 338 } 339 } 340 341 /* 342 * endnetconfig() may be called to "unbind" or "close" the netconfig database 343 * when processing is complete, releasing resources for reuse. endnetconfig() 344 * may not be called before setnetconfig(). endnetconfig() returns 0 on 345 * success and -1 on failure (for example, if setnetconfig() was not called 346 * previously). 347 */ 348 int 349 endnetconfig(handlep) 350 void *handlep; 351 { 352 struct netconfig_vars *nc_handlep = (struct netconfig_vars *)handlep; 353 354 struct netconfig_list *q, *p; 355 356 /* 357 * Verify that handle is valid 358 */ 359 if (nc_handlep == NULL || (nc_handlep->valid != NC_VALID && 360 nc_handlep->valid != NC_STORAGE)) { 361 nc_error = NC_NOTINIT; 362 return (-1); 363 } 364 365 /* 366 * Return 0 if anyone still needs it. 367 */ 368 nc_handlep->valid = NC_INVALID; 369 nc_handlep->flag = 0; 370 nc_handlep->nc_configs = NULL; 371 if (--ni.ref > 0) { 372 free(nc_handlep); 373 return(0); 374 } 375 376 /* 377 * Noone needs these entries anymore, then frees them. 378 * Make sure all info in netconfig_info structure has been reinitialized. 379 */ 380 q = p = ni.head; 381 ni.eof = ni.ref = 0; 382 ni.head = NULL; 383 ni.tail = NULL; 384 while (q) { 385 p = q->next; 386 if (q->ncp->nc_lookups != NULL) free(q->ncp->nc_lookups); 387 free(q->ncp); 388 free(q->linep); 389 free(q); 390 q = p; 391 } 392 free(nc_handlep); 393 394 fclose(nc_file); 395 nc_file = NULL; 396 return (0); 397 } 398 399 /* 400 * getnetconfigent(netid) returns a pointer to the struct netconfig structure 401 * corresponding to netid. It returns NULL if netid is invalid (that is, does 402 * not name an entry in the netconfig database). It returns NULL and sets 403 * errno in case of failure (for example, if the netconfig database cannot be 404 * opened). 405 */ 406 407 struct netconfig * 408 getnetconfigent(netid) 409 char *netid; 410 { 411 FILE *file; /* NETCONFIG db's file pointer */ 412 char *linep; /* holds current netconfig line */ 413 char *stringp; /* temporary string pointer */ 414 struct netconfig *ncp = NULL; /* returned value */ 415 struct netconfig_list *list; /* pointer to cache list */ 416 417 if (netid == NULL || strlen(netid) == 0) { 418 return (NULL); 419 } 420 421 /* 422 * Look up table if the entries have already been read and parsed in 423 * getnetconfig(), then copy this entry into a buffer and return it. 424 * If we cannot find the entry in the current list and there are more 425 * entries in the netconfig db that has not been read, we then read the 426 * db and try find the match netid. 427 * If all the netconfig db has been read and placed into the list and 428 * there is no match for the netid, return NULL. 429 */ 430 if (ni.head != NULL) { 431 for (list = ni.head; list; list = list->next) { 432 if (strcmp(list->ncp->nc_netid, netid) == 0) { 433 return(dup_ncp(list->ncp)); 434 } 435 } 436 if (ni.eof == 1) /* that's all the entries */ 437 return(NULL); 438 } 439 440 441 if ((file = fopen(NETCONFIG, "r")) == NULL) { 442 return (NULL); 443 } 444 445 if ((linep = malloc(MAXNETCONFIGLINE)) == NULL) { 446 fclose(file); 447 return (NULL); 448 } 449 do { 450 int len; 451 char *tmpp; /* tmp string pointer */ 452 453 do { 454 if ((stringp = fgets(linep, MAXNETCONFIGLINE, file)) == NULL) { 455 break; 456 } 457 } while (*stringp == '#'); 458 if (stringp == NULL) { /* eof */ 459 break; 460 } 461 if ((tmpp = strpbrk(stringp, "\t ")) == NULL) { /* can't parse file */ 462 nc_error = NC_BADFILE; 463 break; 464 } 465 if (strlen(netid) == (len = tmpp - stringp) && /* a match */ 466 strncmp(stringp, netid, len) == 0) { 467 if ((ncp = (struct netconfig *) 468 malloc(sizeof (struct netconfig))) == NULL) { 469 break; 470 } 471 ncp->nc_lookups = NULL; 472 if (parse_ncp(linep, ncp) == -1) { 473 free(ncp); 474 ncp = NULL; 475 } 476 break; 477 } 478 } while (stringp != NULL); 479 if (ncp == NULL) { 480 free(linep); 481 } 482 fclose(file); 483 return(ncp); 484 } 485 486 /* 487 * freenetconfigent(netconfigp) frees the netconfig structure pointed to by 488 * netconfigp (previously returned by getnetconfigent()). 489 */ 490 491 void 492 freenetconfigent(netconfigp) 493 struct netconfig *netconfigp; 494 { 495 if (netconfigp != NULL) { 496 free(netconfigp->nc_netid); /* holds all netconfigp's strings */ 497 if (netconfigp->nc_lookups != NULL) 498 free(netconfigp->nc_lookups); 499 free(netconfigp); 500 } 501 return; 502 } 503 504 /* 505 * Parse line and stuff it in a struct netconfig 506 * Typical line might look like: 507 * udp tpi_cots vb inet udp /dev/udp /usr/lib/ip.so,/usr/local/ip.so 508 * 509 * We return -1 if any of the tokens don't parse, or malloc fails. 510 * 511 * Note that we modify stringp (putting NULLs after tokens) and 512 * we set the ncp's string field pointers to point to these tokens within 513 * stringp. 514 */ 515 516 static int 517 parse_ncp(stringp, ncp) 518 char *stringp; /* string to parse */ 519 struct netconfig *ncp; /* where to put results */ 520 { 521 char *tokenp; /* for processing tokens */ 522 523 nc_error = NC_BADFILE; /* nearly anything that breaks is for this reason */ 524 stringp[strlen(stringp)-1] = '\0'; /* get rid of newline */ 525 /* netid */ 526 if ((ncp->nc_netid = strtok(stringp, "\t ")) == NULL) { 527 return (-1); 528 } 529 530 /* semantics */ 531 if ((tokenp = strtok(NULL, "\t ")) == NULL) { 532 return (-1); 533 } 534 if (strcmp(tokenp, NC_TPI_COTS_ORD_S) == 0) 535 ncp->nc_semantics = NC_TPI_COTS_ORD; 536 else if (strcmp(tokenp, NC_TPI_COTS_S) == 0) 537 ncp->nc_semantics = NC_TPI_COTS; 538 else if (strcmp(tokenp, NC_TPI_CLTS_S) == 0) 539 ncp->nc_semantics = NC_TPI_CLTS; 540 else if (strcmp(tokenp, NC_TPI_RAW_S) == 0) 541 ncp->nc_semantics = NC_TPI_RAW; 542 else 543 return (-1); 544 545 /* flags */ 546 if ((tokenp = strtok(NULL, "\t ")) == NULL) { 547 return (-1); 548 } 549 for (ncp->nc_flag = NC_NOFLAG; *tokenp != '\0'; 550 tokenp++) { 551 switch (*tokenp) { 552 case NC_NOFLAG_C: 553 break; 554 case NC_VISIBLE_C: 555 ncp->nc_flag |= NC_VISIBLE; 556 break; 557 case NC_BROADCAST_C: 558 ncp->nc_flag |= NC_BROADCAST; 559 break; 560 default: 561 return (-1); 562 } 563 } 564 /* protocol family */ 565 if ((ncp->nc_protofmly = strtok(NULL, "\t ")) == NULL) { 566 return (-1); 567 } 568 /* protocol name */ 569 if ((ncp->nc_proto = strtok(NULL, "\t ")) == NULL) { 570 return (-1); 571 } 572 /* network device */ 573 if ((ncp->nc_device = strtok(NULL, "\t ")) == NULL) { 574 return (-1); 575 } 576 if ((tokenp = strtok(NULL, "\t ")) == NULL) { 577 return (-1); 578 } 579 if (strcmp(tokenp, NC_NOLOOKUP) == 0) { 580 ncp->nc_nlookups = 0; 581 ncp->nc_lookups = NULL; 582 } else { 583 char *cp; /* tmp string */ 584 585 if (ncp->nc_lookups != NULL) /* from last visit */ 586 free(ncp->nc_lookups); 587 /* preallocate one string pointer */ 588 ncp->nc_lookups = (char **)malloc(sizeof (char *)); 589 ncp->nc_nlookups = 0; 590 while ((cp = tokenp) != NULL) { 591 tokenp = _get_next_token(cp, ','); 592 ncp->nc_lookups[ncp->nc_nlookups++] = cp; 593 ncp->nc_lookups = (char **)realloc(ncp->nc_lookups, 594 (ncp->nc_nlookups+1) *sizeof(char *)); /* for next loop */ 595 } 596 } 597 return (0); 598 } 599 600 601 /* 602 * Returns a string describing the reason for failure. 603 */ 604 char * 605 nc_sperror() 606 { 607 char *message; 608 609 switch(nc_error) { 610 case NC_NONETCONFIG: 611 message = _nc_errors[0]; 612 break; 613 case NC_NOMEM: 614 message = _nc_errors[1]; 615 break; 616 case NC_NOTINIT: 617 message = _nc_errors[2]; 618 break; 619 case NC_BADFILE: 620 message = _nc_errors[3]; 621 break; 622 default: 623 message = "Unknown network selection error"; 624 } 625 return (message); 626 } 627 628 /* 629 * Prints a message onto standard error describing the reason for failure. 630 */ 631 void 632 nc_perror(s) 633 const char *s; 634 { 635 fprintf(stderr, "%s: %s", s, nc_sperror()); 636 } 637 638 /* 639 * Duplicates the matched netconfig buffer. 640 */ 641 static struct netconfig * 642 dup_ncp(ncp) 643 struct netconfig *ncp; 644 { 645 struct netconfig *p; 646 char *tmp; 647 int i; 648 649 if ((tmp=malloc(MAXNETCONFIGLINE)) == NULL) 650 return(NULL); 651 if ((p=(struct netconfig *)malloc(sizeof(struct netconfig))) == NULL) { 652 free(tmp); 653 return(NULL); 654 } 655 /* 656 * First we dup all the data from matched netconfig buffer. Then we 657 * adjust some of the member pointer to a pre-allocated buffer where 658 * contains part of the data. 659 * To follow the convention used in parse_ncp(), we store all the 660 * neccessary information in the pre-allocated buffer and let each 661 * of the netconfig char pointer member point to the right address 662 * in the buffer. 663 */ 664 *p = *ncp; 665 p->nc_netid = (char *)strcpy(tmp,ncp->nc_netid); 666 tmp = strchr(tmp, NULL) + 1; 667 p->nc_protofmly = (char *)strcpy(tmp,ncp->nc_protofmly); 668 tmp = strchr(tmp, NULL) + 1; 669 p->nc_proto = (char *)strcpy(tmp,ncp->nc_proto); 670 tmp = strchr(tmp, NULL) + 1; 671 p->nc_device = (char *)strcpy(tmp,ncp->nc_device); 672 p->nc_lookups = (char **)malloc((p->nc_nlookups+1) * sizeof(char *)); 673 if (p->nc_lookups == NULL) { 674 free(p->nc_netid); 675 return(NULL); 676 } 677 for (i=0; i < p->nc_nlookups; i++) { 678 tmp = strchr(tmp, NULL) + 1; 679 p->nc_lookups[i] = (char *)strcpy(tmp,ncp->nc_lookups[i]); 680 } 681 return(p); 682 } 683