1 /* $NetBSD: getnetconfig.c,v 1.17 2008/04/25 17:44:44 christos 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 #include <sys/cdefs.h> 34 #if defined(LIBC_SCCS) && !defined(lint) 35 #if 0 36 static char sccsid[] = "@(#)getnetconfig.c 1.12 91/12/19 SMI"; 37 #else 38 __RCSID("$NetBSD: getnetconfig.c,v 1.17 2008/04/25 17:44:44 christos Exp $"); 39 #endif 40 #endif 41 42 /* 43 * Copyright (c) 1989 by Sun Microsystems, Inc. 44 */ 45 46 #include "namespace.h" 47 #include "reentrant.h" 48 #include <stdio.h> 49 #include <assert.h> 50 #include <errno.h> 51 #include <netconfig.h> 52 #include <stddef.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <rpc/rpc.h> 56 #include "rpc_internal.h" 57 58 #ifdef __weak_alias 59 __weak_alias(getnetconfig,_getnetconfig) 60 __weak_alias(setnetconfig,_setnetconfig) 61 __weak_alias(endnetconfig,_endnetconfig) 62 __weak_alias(getnetconfigent,_getnetconfigent) 63 __weak_alias(freenetconfigent,_freenetconfigent) 64 __weak_alias(nc_perror,_nc_perror) 65 __weak_alias(nc_sperror,_nc_sperror) 66 #endif 67 68 /* 69 * The five library routines in this file provide application access to the 70 * system network configuration database, /etc/netconfig. In addition to the 71 * netconfig database and the routines for accessing it, the environment 72 * variable NETPATH and its corresponding routines in getnetpath.c may also be 73 * used to specify the network transport to be used. 74 */ 75 76 77 /* 78 * netconfig errors 79 */ 80 81 #define NC_NONETCONFIG ENOENT 82 #define NC_NOMEM ENOMEM 83 #define NC_NOTINIT EINVAL /* setnetconfig was not called first */ 84 #define NC_BADFILE EBADF /* format for netconfig file is bad */ 85 86 /* 87 * semantics as strings (should be in netconfig.h) 88 */ 89 #define NC_TPI_CLTS_S "tpi_clts" 90 #define NC_TPI_COTS_S "tpi_cots" 91 #define NC_TPI_COTS_ORD_S "tpi_cots_ord" 92 #define NC_TPI_RAW_S "tpi_raw" 93 94 /* 95 * flags as characters (also should be in netconfig.h) 96 */ 97 #define NC_NOFLAG_C '-' 98 #define NC_VISIBLE_C 'v' 99 #define NC_BROADCAST_C 'b' 100 101 /* 102 * Character used to indicate there is no name-to-address lookup library 103 */ 104 #define NC_NOLOOKUP "-" 105 106 static const char * const _nc_errors[] = { 107 "Netconfig database not found", 108 "Not enough memory", 109 "Not initialized", 110 "Netconfig database has invalid format" 111 }; 112 113 struct netconfig_info { 114 int eof; /* all entries has been read */ 115 int ref; /* # of times setnetconfig() has been called */ 116 struct netconfig_list *head; /* head of the list */ 117 struct netconfig_list *tail; /* last of the list */ 118 }; 119 120 struct netconfig_list { 121 char *linep; /* hold line read from netconfig */ 122 struct netconfig *ncp; 123 struct netconfig_list *next; 124 }; 125 126 struct netconfig_vars { 127 int valid; /* token that indicates valid netconfig_vars */ 128 int flag; /* first time flag */ 129 struct netconfig_list *nc_configs; 130 /* pointer to the current netconfig entry */ 131 }; 132 133 #define NC_VALID 0xfeed 134 #define NC_STORAGE 0xf00d 135 #define NC_INVALID 0 136 137 138 static int *__nc_error __P((void)); 139 static int parse_ncp __P((char *, struct netconfig *)); 140 static struct netconfig *dup_ncp __P((struct netconfig *)); 141 142 143 static FILE *nc_file; /* for netconfig db */ 144 static struct netconfig_info ni = { 0, 0, NULL, NULL}; 145 146 #define MAXNETCONFIGLINE 1000 147 148 #ifdef _REENTRANT 149 static thread_key_t nc_key; 150 static once_t nc_once = ONCE_INITIALIZER; 151 152 static void 153 __nc_error_setup(void) 154 { 155 thr_keycreate(&nc_key, free); 156 } 157 #endif 158 159 static int * 160 __nc_error() 161 { 162 #ifdef _REENTRANT 163 extern int __isthreaded; 164 int *nc_addr = NULL; 165 #endif 166 static int nc_error = 0; 167 168 #ifdef _REENTRANT 169 if (__isthreaded == 0) 170 return &nc_error; 171 thr_once(&nc_once, __nc_error_setup); 172 nc_addr = thr_getspecific(nc_key) ; 173 if (nc_addr == NULL) { 174 nc_addr = malloc(sizeof (int)); 175 if (nc_addr == NULL) 176 return &nc_error; 177 if (thr_setspecific(nc_key, (void *) nc_addr) != 0) { 178 if (nc_addr) 179 free(nc_addr); 180 return &nc_error; 181 } 182 *nc_addr = 0; 183 } 184 return nc_addr; 185 #else 186 return &nc_error; 187 #endif 188 } 189 190 #define nc_error (*(__nc_error())) 191 /* 192 * A call to setnetconfig() establishes a /etc/netconfig "session". A session 193 * "handle" is returned on a successful call. At the start of a session (after 194 * a call to setnetconfig()) searches through the /etc/netconfig database will 195 * proceed from the start of the file. The session handle must be passed to 196 * getnetconfig() to parse the file. Each call to getnetconfig() using the 197 * current handle will process one subsequent entry in /etc/netconfig. 198 * setnetconfig() must be called before the first call to getnetconfig(). 199 * (Handles are used to allow for nested calls to setnetpath()). 200 * 201 * A new session is established with each call to setnetconfig(), with a new 202 * handle being returned on each call. Previously established sessions remain 203 * active until endnetconfig() is called with that session's handle as an 204 * argument. 205 * 206 * setnetconfig() need *not* be called before a call to getnetconfigent(). 207 * setnetconfig() returns a NULL pointer on failure (for example, if 208 * the netconfig database is not present). 209 */ 210 void * 211 setnetconfig() 212 { 213 struct netconfig_vars *nc_vars; 214 215 if ((nc_vars = malloc(sizeof(*nc_vars))) == NULL) { 216 return(NULL); 217 } 218 219 /* 220 * For multiple calls, i.e. nc_file is not NULL, we just return the 221 * handle without reopening the netconfig db. 222 */ 223 ni.ref++; 224 if ((nc_file != NULL) || (nc_file = fopen(NETCONFIG, "r")) != NULL) { 225 nc_vars->valid = NC_VALID; 226 nc_vars->flag = 0; 227 nc_vars->nc_configs = ni.head; 228 return ((void *)nc_vars); 229 } 230 ni.ref--; 231 nc_error = NC_NONETCONFIG; 232 free(nc_vars); 233 return (NULL); 234 } 235 236 237 /* 238 * When first called, getnetconfig() returns a pointer to the first entry in 239 * the netconfig database, formatted as a struct netconfig. On each subsequent 240 * call, getnetconfig() returns a pointer to the next entry in the database. 241 * getnetconfig() can thus be used to search the entire netconfig file. 242 * getnetconfig() returns NULL at end of file. 243 */ 244 245 struct netconfig * 246 getnetconfig(handlep) 247 void *handlep; 248 { 249 struct netconfig_vars *ncp = (struct netconfig_vars *)handlep; 250 char *stringp; /* tmp string pointer */ 251 struct netconfig_list *list; 252 struct netconfig *np; 253 254 /* 255 * Verify that handle is valid 256 */ 257 if (ncp == NULL || nc_file == NULL) { 258 nc_error = NC_NOTINIT; 259 return (NULL); 260 } 261 262 switch (ncp->valid) { 263 case NC_VALID: 264 /* 265 * If entry has already been read into the list, 266 * we return the entry in the linked list. 267 * If this is the first time call, check if there are any 268 * entries in linked list. If no entries, we need to read the 269 * netconfig db. 270 * If we have been here and the next entry is there, we just 271 * return it. 272 */ 273 if (ncp->flag == 0) { /* first time */ 274 ncp->flag = 1; 275 ncp->nc_configs = ni.head; 276 if (ncp->nc_configs != NULL) /* entry already exist */ 277 return(ncp->nc_configs->ncp); 278 } 279 else if (ncp->nc_configs != NULL && 280 ncp->nc_configs->next != NULL) { 281 ncp->nc_configs = ncp->nc_configs->next; 282 return(ncp->nc_configs->ncp); 283 } 284 285 /* 286 * If we cannot find the entry in the list and is end of file, 287 * we give up. 288 */ 289 if (ni.eof == 1) 290 return(NULL); 291 break; 292 default: 293 nc_error = NC_NOTINIT; 294 return (NULL); 295 } 296 297 stringp = malloc(MAXNETCONFIGLINE); 298 if (stringp == NULL) 299 return (NULL); 300 301 #ifdef MEM_CHK 302 if (malloc_verify() == 0) { 303 fprintf(stderr, "memory heap corrupted in getnetconfig\n"); 304 exit(1); 305 } 306 #endif 307 308 /* 309 * Read a line from netconfig file. 310 */ 311 do { 312 if (fgets(stringp, MAXNETCONFIGLINE, nc_file) == NULL) { 313 free(stringp); 314 ni.eof = 1; 315 return (NULL); 316 } 317 } while (*stringp == '#'); 318 319 list = malloc(sizeof(*list)); 320 if (list == NULL) { 321 free(stringp); 322 return(NULL); 323 } 324 np = malloc(sizeof(*np)); 325 if (np == NULL) { 326 free(stringp); 327 free(list); 328 return(NULL); 329 } 330 list->ncp = np; 331 list->next = NULL; 332 list->ncp->nc_lookups = NULL; 333 list->linep = stringp; 334 if (parse_ncp(stringp, list->ncp) == -1) { 335 free(stringp); 336 free(np); 337 free(list); 338 return (NULL); 339 } else { 340 /* 341 * If this is the first entry that's been read, it is the 342 * head of the list. If not, put the entry at the end of 343 * the list. Reposition the current pointer of the handle to 344 * the last entry in the list. 345 */ 346 if (ni.head == NULL) /* first entry */ 347 ni.head = ni.tail = list; 348 else { 349 ni.tail->next = list; 350 ni.tail = ni.tail->next; 351 } 352 ncp->nc_configs = ni.tail; 353 return(ni.tail->ncp); 354 } 355 } 356 357 /* 358 * endnetconfig() may be called to "unbind" or "close" the netconfig database 359 * when processing is complete, releasing resources for reuse. endnetconfig() 360 * may not be called before setnetconfig(). endnetconfig() returns 0 on 361 * success and -1 on failure (for example, if setnetconfig() was not called 362 * previously). 363 */ 364 int 365 endnetconfig(handlep) 366 void *handlep; 367 { 368 struct netconfig_vars *nc_handlep = (struct netconfig_vars *)handlep; 369 370 struct netconfig_list *q, *p; 371 372 /* 373 * Verify that handle is valid 374 */ 375 if (nc_handlep == NULL || (nc_handlep->valid != NC_VALID && 376 nc_handlep->valid != NC_STORAGE)) { 377 nc_error = NC_NOTINIT; 378 return (-1); 379 } 380 381 /* 382 * Return 0 if anyone still needs it. 383 */ 384 nc_handlep->valid = NC_INVALID; 385 nc_handlep->flag = 0; 386 nc_handlep->nc_configs = NULL; 387 if (--ni.ref > 0) { 388 free(nc_handlep); 389 return(0); 390 } 391 392 /* 393 * Noone needs these entries anymore, then frees them. 394 * Make sure all info in netconfig_info structure has been 395 * reinitialized. 396 */ 397 q = p = ni.head; 398 ni.eof = ni.ref = 0; 399 ni.head = NULL; 400 ni.tail = NULL; 401 while (q) { 402 p = q->next; 403 if (q->ncp->nc_lookups != NULL) free(q->ncp->nc_lookups); 404 free(q->ncp); 405 free(q->linep); 406 free(q); 407 q = p; 408 } 409 free(nc_handlep); 410 411 fclose(nc_file); 412 nc_file = NULL; 413 return (0); 414 } 415 416 /* 417 * getnetconfigent(netid) returns a pointer to the struct netconfig structure 418 * corresponding to netid. It returns NULL if netid is invalid (that is, does 419 * not name an entry in the netconfig database). It returns NULL and sets 420 * errno in case of failure (for example, if the netconfig database cannot be 421 * opened). 422 */ 423 424 struct netconfig * 425 getnetconfigent(netid) 426 const char *netid; 427 { 428 FILE *file; /* NETCONFIG db's file pointer */ 429 char *linep; /* holds current netconfig line */ 430 char *stringp; /* temporary string pointer */ 431 struct netconfig *ncp = NULL; /* returned value */ 432 struct netconfig_list *list; /* pointer to cache list */ 433 434 if (netid == NULL || strlen(netid) == 0) 435 return (NULL); 436 437 /* 438 * Look up table if the entries have already been read and parsed in 439 * getnetconfig(), then copy this entry into a buffer and return it. 440 * If we cannot find the entry in the current list and there are more 441 * entries in the netconfig db that has not been read, we then read the 442 * db and try find the match netid. 443 * If all the netconfig db has been read and placed into the list and 444 * there is no match for the netid, return NULL. 445 */ 446 if (ni.head != NULL) { 447 for (list = ni.head; list; list = list->next) { 448 if (strcmp(list->ncp->nc_netid, netid) == 0) 449 return(dup_ncp(list->ncp)); 450 } 451 if (ni.eof == 1) /* that's all the entries */ 452 return(NULL); 453 } 454 455 if ((file = fopen(NETCONFIG, "r")) == NULL) 456 return (NULL); 457 458 if ((linep = malloc(MAXNETCONFIGLINE)) == NULL) { 459 fclose(file); 460 return (NULL); 461 } 462 do { 463 ptrdiff_t len; 464 char *tmpp; /* tmp string pointer */ 465 466 do { 467 if ((stringp = fgets(linep, MAXNETCONFIGLINE, file)) 468 == NULL) 469 break; 470 } while (*stringp == '#'); 471 if (stringp == NULL) /* eof */ 472 break; 473 if ((tmpp = strpbrk(stringp, "\t ")) == NULL) { 474 /* can't parse file */ 475 nc_error = NC_BADFILE; 476 break; 477 } 478 if (strlen(netid) == (size_t) (len = tmpp - stringp) && /* a match */ 479 strncmp(stringp, netid, (size_t)len) == 0) { 480 if ((ncp = malloc(sizeof(*ncp))) == NULL) 481 break; 482 ncp->nc_lookups = NULL; 483 if (parse_ncp(linep, ncp) == -1) { 484 free(ncp); 485 ncp = NULL; 486 } 487 break; 488 } 489 } while (stringp != NULL); 490 if (ncp == NULL) 491 free(linep); 492 fclose(file); 493 return(ncp); 494 } 495 496 /* 497 * freenetconfigent(netconfigp) frees the netconfig structure pointed to by 498 * netconfigp (previously returned by getnetconfigent()). 499 */ 500 501 void 502 freenetconfigent(netconfigp) 503 struct netconfig *netconfigp; 504 { 505 if (netconfigp != NULL) { 506 /* holds all netconfigp's strings */ 507 free(netconfigp->nc_netid); 508 if (netconfigp->nc_lookups != NULL) 509 free(netconfigp->nc_lookups); 510 free(netconfigp); 511 } 512 } 513 514 /* 515 * Parse line and stuff it in a struct netconfig 516 * Typical line might look like: 517 * udp tpi_cots vb inet udp /dev/udp /usr/lib/ip.so,/usr/local/ip.so 518 * 519 * We return -1 if any of the tokens don't parse, or malloc fails. 520 * 521 * Note that we modify stringp (putting NULLs after tokens) and 522 * we set the ncp's string field pointers to point to these tokens within 523 * stringp. 524 */ 525 526 static int 527 parse_ncp(stringp, ncp) 528 char *stringp; /* string to parse */ 529 struct netconfig *ncp; /* where to put results */ 530 { 531 char *tokenp; /* for processing tokens */ 532 char *lasts; 533 534 _DIAGASSERT(stringp != NULL); 535 _DIAGASSERT(ncp != NULL); 536 537 nc_error = NC_BADFILE; 538 /* nearly anything that breaks is for this reason */ 539 stringp[strlen(stringp)-1] = '\0'; /* get rid of newline */ 540 /* netid */ 541 if ((ncp->nc_netid = strtok_r(stringp, "\t ", &lasts)) == NULL) 542 return (-1); 543 544 /* semantics */ 545 if ((tokenp = strtok_r(NULL, "\t ", &lasts)) == NULL) 546 return (-1); 547 if (strcmp(tokenp, NC_TPI_COTS_ORD_S) == 0) 548 ncp->nc_semantics = NC_TPI_COTS_ORD; 549 else if (strcmp(tokenp, NC_TPI_COTS_S) == 0) 550 ncp->nc_semantics = NC_TPI_COTS; 551 else if (strcmp(tokenp, NC_TPI_CLTS_S) == 0) 552 ncp->nc_semantics = NC_TPI_CLTS; 553 else if (strcmp(tokenp, NC_TPI_RAW_S) == 0) 554 ncp->nc_semantics = NC_TPI_RAW; 555 else 556 return (-1); 557 558 /* flags */ 559 if ((tokenp = strtok_r(NULL, "\t ", &lasts)) == NULL) 560 return (-1); 561 for (ncp->nc_flag = NC_NOFLAG; *tokenp != '\0'; tokenp++) { 562 switch (*tokenp) { 563 case NC_NOFLAG_C: 564 break; 565 case NC_VISIBLE_C: 566 ncp->nc_flag |= NC_VISIBLE; 567 break; 568 case NC_BROADCAST_C: 569 ncp->nc_flag |= NC_BROADCAST; 570 break; 571 default: 572 return (-1); 573 } 574 } 575 /* protocol family */ 576 if ((ncp->nc_protofmly = strtok_r(NULL, "\t ", &lasts)) == NULL) 577 return (-1); 578 /* protocol name */ 579 if ((ncp->nc_proto = strtok_r(NULL, "\t ", &lasts)) == NULL) 580 return (-1); 581 /* network device */ 582 if ((ncp->nc_device = strtok_r(NULL, "\t ", &lasts)) == NULL) 583 return (-1); 584 if ((tokenp = strtok_r(NULL, "\t ", &lasts)) == NULL) 585 return (-1); 586 if (strcmp(tokenp, NC_NOLOOKUP) == 0) { 587 ncp->nc_nlookups = 0; 588 ncp->nc_lookups = NULL; 589 } else { 590 char *cp; /* tmp string */ 591 592 if (ncp->nc_lookups != NULL) /* from last visit */ 593 free(ncp->nc_lookups); 594 /* preallocate one string pointer */ 595 ncp->nc_lookups = malloc(sizeof(*ncp->nc_lookups)); 596 ncp->nc_nlookups = 0; 597 while ((cp = tokenp) != NULL) { 598 tokenp = _get_next_token(cp, ','); 599 ncp->nc_lookups[(size_t)ncp->nc_nlookups++] = cp; 600 ncp->nc_lookups = (char **) 601 realloc(ncp->nc_lookups, 602 (size_t)(ncp->nc_nlookups+1) *sizeof(char *)); 603 /* for next loop */ 604 } 605 } 606 return (0); 607 } 608 609 /* 610 * Returns a string describing the reason for failure. 611 */ 612 char * 613 nc_sperror() 614 { 615 const char *message; 616 617 switch(nc_error) { 618 case NC_NONETCONFIG: 619 message = _nc_errors[0]; 620 break; 621 case NC_NOMEM: 622 message = _nc_errors[1]; 623 break; 624 case NC_NOTINIT: 625 message = _nc_errors[2]; 626 break; 627 case NC_BADFILE: 628 message = _nc_errors[3]; 629 break; 630 default: 631 message = "Unknown network selection error"; 632 } 633 return __UNCONST(message); 634 } 635 636 /* 637 * Prints a message onto standard error describing the reason for failure. 638 */ 639 void 640 nc_perror(s) 641 const char *s; 642 { 643 644 _DIAGASSERT(s != NULL); 645 646 fprintf(stderr, "%s: %s", s, nc_sperror()); 647 } 648 649 /* 650 * Duplicates the matched netconfig buffer. 651 */ 652 static struct netconfig * 653 dup_ncp(ncp) 654 struct netconfig *ncp; 655 { 656 struct netconfig *p; 657 char *tmp; 658 u_int i; 659 660 _DIAGASSERT(ncp != NULL); 661 662 if ((tmp = malloc(MAXNETCONFIGLINE)) == NULL) 663 return(NULL); 664 if ((p = malloc(sizeof(*p))) == NULL) { 665 free(tmp); 666 return(NULL); 667 } 668 /* 669 * First we dup all the data from matched netconfig buffer. Then we 670 * adjust some of the member pointer to a pre-allocated buffer where 671 * contains part of the data. 672 * To follow the convention used in parse_ncp(), we store all the 673 * necessary information in the pre-allocated buffer and let each 674 * of the netconfig char pointer member point to the right address 675 * in the buffer. 676 */ 677 *p = *ncp; 678 p->nc_netid = (char *)strcpy(tmp,ncp->nc_netid); 679 tmp = strchr(tmp, '\0') + 1; 680 p->nc_protofmly = (char *)strcpy(tmp,ncp->nc_protofmly); 681 tmp = strchr(tmp, '\0') + 1; 682 p->nc_proto = (char *)strcpy(tmp,ncp->nc_proto); 683 tmp = strchr(tmp, '\0') + 1; 684 p->nc_device = (char *)strcpy(tmp,ncp->nc_device); 685 p->nc_lookups = malloc((size_t)(p->nc_nlookups+1) * sizeof(char *)); 686 if (p->nc_lookups == NULL) { 687 free(p->nc_netid); 688 free(p); 689 return(NULL); 690 } 691 for (i=0; i < p->nc_nlookups; i++) { 692 tmp = strchr(tmp, '\0') + 1; 693 p->nc_lookups[i] = strcpy(tmp,ncp->nc_lookups[i]); 694 } 695 return(p); 696 } 697