1 /* $NetBSD: getnetconfig.c,v 1.21 2013/03/11 20:19:29 tron Exp $ */ 2 3 /* 4 * Copyright (c) 2010, Oracle America, Inc. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: 9 * 10 * * Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * * Redistributions in binary form must reproduce the above 13 * copyright notice, this list of conditions and the following 14 * disclaimer in the documentation and/or other materials 15 * provided with the distribution. 16 * * Neither the name of the "Oracle America, Inc." nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 25 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 #if defined(LIBC_SCCS) && !defined(lint) 36 #if 0 37 static char sccsid[] = "@(#)getnetconfig.c 1.12 91/12/19 SMI"; 38 #else 39 __RCSID("$NetBSD: getnetconfig.c,v 1.21 2013/03/11 20:19:29 tron Exp $"); 40 #endif 41 #endif 42 43 /* 44 * Copyright (c) 1989 by Sun Microsystems, Inc. 45 */ 46 47 #include "namespace.h" 48 #include "reentrant.h" 49 #include <stdio.h> 50 #include <assert.h> 51 #include <errno.h> 52 #include <netconfig.h> 53 #include <stddef.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <rpc/rpc.h> 57 #include "rpc_internal.h" 58 59 #ifdef __weak_alias 60 __weak_alias(getnetconfig,_getnetconfig) 61 __weak_alias(setnetconfig,_setnetconfig) 62 __weak_alias(endnetconfig,_endnetconfig) 63 __weak_alias(getnetconfigent,_getnetconfigent) 64 __weak_alias(freenetconfigent,_freenetconfigent) 65 __weak_alias(nc_perror,_nc_perror) 66 __weak_alias(nc_sperror,_nc_sperror) 67 #endif 68 69 /* 70 * The five library routines in this file provide application access to the 71 * system network configuration database, /etc/netconfig. In addition to the 72 * netconfig database and the routines for accessing it, the environment 73 * variable NETPATH and its corresponding routines in getnetpath.c may also be 74 * used to specify the network transport to be used. 75 */ 76 77 78 /* 79 * netconfig errors 80 */ 81 82 #define NC_NONETCONFIG ENOENT 83 #define NC_NOMEM ENOMEM 84 #define NC_NOTINIT EINVAL /* setnetconfig was not called first */ 85 #define NC_BADFILE EBADF /* format for netconfig file is bad */ 86 87 /* 88 * semantics as strings (should be in netconfig.h) 89 */ 90 #define NC_TPI_CLTS_S "tpi_clts" 91 #define NC_TPI_COTS_S "tpi_cots" 92 #define NC_TPI_COTS_ORD_S "tpi_cots_ord" 93 #define NC_TPI_RAW_S "tpi_raw" 94 95 /* 96 * flags as characters (also should be in netconfig.h) 97 */ 98 #define NC_NOFLAG_C '-' 99 #define NC_VISIBLE_C 'v' 100 #define NC_BROADCAST_C 'b' 101 102 /* 103 * Character used to indicate there is no name-to-address lookup library 104 */ 105 #define NC_NOLOOKUP "-" 106 107 static const char * const _nc_errors[] = { 108 "Netconfig database not found", 109 "Not enough memory", 110 "Not initialized", 111 "Netconfig database has invalid format" 112 }; 113 114 struct netconfig_info { 115 int eof; /* all entries has been read */ 116 int ref; /* # of times setnetconfig() has been called */ 117 struct netconfig_list *head; /* head of the list */ 118 struct netconfig_list *tail; /* last of the list */ 119 }; 120 121 struct netconfig_list { 122 char *linep; /* hold line read from netconfig */ 123 struct netconfig *ncp; 124 struct netconfig_list *next; 125 }; 126 127 struct netconfig_vars { 128 int valid; /* token that indicates valid netconfig_vars */ 129 int flag; /* first time flag */ 130 struct netconfig_list *nc_configs; 131 /* pointer to the current netconfig entry */ 132 }; 133 134 #define NC_VALID 0xfeed 135 #define NC_STORAGE 0xf00d 136 #define NC_INVALID 0 137 138 139 static int *__nc_error(void); 140 static int parse_ncp(char *, struct netconfig *); 141 static struct netconfig *dup_ncp(struct netconfig *); 142 143 144 static FILE *nc_file; /* for netconfig db */ 145 static struct netconfig_info ni = { 0, 0, NULL, NULL}; 146 147 #define MAXNETCONFIGLINE 1000 148 149 #ifdef _REENTRANT 150 static thread_key_t nc_key; 151 static once_t nc_once = ONCE_INITIALIZER; 152 153 static void 154 __nc_error_setup(void) 155 { 156 thr_keycreate(&nc_key, free); 157 } 158 #endif 159 160 static int * 161 __nc_error(void) 162 { 163 #ifdef _REENTRANT 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(void) 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, "re")) != 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(void *handlep) 247 { 248 struct netconfig_vars *ncp = (struct netconfig_vars *)handlep; 249 char *stringp; /* tmp string pointer */ 250 struct netconfig_list *list; 251 struct netconfig *np; 252 253 /* 254 * Verify that handle is valid 255 */ 256 if (ncp == NULL || nc_file == NULL) { 257 nc_error = NC_NOTINIT; 258 return (NULL); 259 } 260 261 switch (ncp->valid) { 262 case NC_VALID: 263 /* 264 * If entry has already been read into the list, 265 * we return the entry in the linked list. 266 * If this is the first time call, check if there are any 267 * entries in linked list. If no entries, we need to read the 268 * netconfig db. 269 * If we have been here and the next entry is there, we just 270 * return it. 271 */ 272 if (ncp->flag == 0) { /* first time */ 273 ncp->flag = 1; 274 ncp->nc_configs = ni.head; 275 if (ncp->nc_configs != NULL) /* entry already exist */ 276 return(ncp->nc_configs->ncp); 277 } 278 else if (ncp->nc_configs != NULL && 279 ncp->nc_configs->next != NULL) { 280 ncp->nc_configs = ncp->nc_configs->next; 281 return(ncp->nc_configs->ncp); 282 } 283 284 /* 285 * If we cannot find the entry in the list and is end of file, 286 * we give up. 287 */ 288 if (ni.eof == 1) 289 return(NULL); 290 break; 291 default: 292 nc_error = NC_NOTINIT; 293 return (NULL); 294 } 295 296 stringp = malloc(MAXNETCONFIGLINE); 297 if (stringp == NULL) 298 return (NULL); 299 300 #ifdef MEM_CHK 301 if (malloc_verify() == 0) { 302 fprintf(stderr, "memory heap corrupted in getnetconfig\n"); 303 exit(1); 304 } 305 #endif 306 307 /* 308 * Read a line from netconfig file. 309 */ 310 do { 311 if (fgets(stringp, MAXNETCONFIGLINE, nc_file) == NULL) { 312 free(stringp); 313 ni.eof = 1; 314 return (NULL); 315 } 316 } while (*stringp == '#'); 317 318 list = malloc(sizeof(*list)); 319 if (list == NULL) { 320 free(stringp); 321 return(NULL); 322 } 323 np = malloc(sizeof(*np)); 324 if (np == NULL) { 325 free(stringp); 326 free(list); 327 return(NULL); 328 } 329 list->ncp = np; 330 list->next = NULL; 331 list->ncp->nc_lookups = NULL; 332 list->linep = stringp; 333 if (parse_ncp(stringp, list->ncp) == -1) { 334 free(stringp); 335 free(np); 336 free(list); 337 return (NULL); 338 } else { 339 /* 340 * If this is the first entry that's been read, it is the 341 * head of the list. If not, put the entry at the end of 342 * the list. Reposition the current pointer of the handle to 343 * the last entry in the list. 344 */ 345 if (ni.head == NULL) /* first entry */ 346 ni.head = ni.tail = list; 347 else { 348 ni.tail->next = list; 349 ni.tail = ni.tail->next; 350 } 351 ncp->nc_configs = ni.tail; 352 return(ni.tail->ncp); 353 } 354 } 355 356 /* 357 * endnetconfig() may be called to "unbind" or "close" the netconfig database 358 * when processing is complete, releasing resources for reuse. endnetconfig() 359 * may not be called before setnetconfig(). endnetconfig() returns 0 on 360 * success and -1 on failure (for example, if setnetconfig() was not called 361 * previously). 362 */ 363 int 364 endnetconfig(void *handlep) 365 { 366 struct netconfig_vars *nc_handlep = (struct netconfig_vars *)handlep; 367 368 struct netconfig_list *q, *p; 369 370 /* 371 * Verify that handle is valid 372 */ 373 if (nc_handlep == NULL || (nc_handlep->valid != NC_VALID && 374 nc_handlep->valid != NC_STORAGE)) { 375 nc_error = NC_NOTINIT; 376 return (-1); 377 } 378 379 /* 380 * Return 0 if anyone still needs it. 381 */ 382 nc_handlep->valid = NC_INVALID; 383 nc_handlep->flag = 0; 384 nc_handlep->nc_configs = NULL; 385 if (--ni.ref > 0) { 386 free(nc_handlep); 387 return(0); 388 } 389 390 /* 391 * Noone needs these entries anymore, then frees them. 392 * Make sure all info in netconfig_info structure has been 393 * reinitialized. 394 */ 395 q = p = ni.head; 396 ni.eof = ni.ref = 0; 397 ni.head = NULL; 398 ni.tail = NULL; 399 while (q) { 400 p = q->next; 401 if (q->ncp->nc_lookups != NULL) free(q->ncp->nc_lookups); 402 free(q->ncp); 403 free(q->linep); 404 free(q); 405 q = p; 406 } 407 free(nc_handlep); 408 409 fclose(nc_file); 410 nc_file = NULL; 411 return (0); 412 } 413 414 /* 415 * getnetconfigent(netid) returns a pointer to the struct netconfig structure 416 * corresponding to netid. It returns NULL if netid is invalid (that is, does 417 * not name an entry in the netconfig database). It returns NULL and sets 418 * errno in case of failure (for example, if the netconfig database cannot be 419 * opened). 420 */ 421 422 struct netconfig * 423 getnetconfigent(const char *netid) 424 { 425 FILE *file; /* NETCONFIG db's file pointer */ 426 char *linep; /* holds current netconfig line */ 427 char *stringp; /* temporary string pointer */ 428 struct netconfig *ncp = NULL; /* returned value */ 429 struct netconfig_list *list; /* pointer to cache list */ 430 431 if (netid == NULL || strlen(netid) == 0) 432 return (NULL); 433 434 /* 435 * Look up table if the entries have already been read and parsed in 436 * getnetconfig(), then copy this entry into a buffer and return it. 437 * If we cannot find the entry in the current list and there are more 438 * entries in the netconfig db that has not been read, we then read the 439 * db and try find the match netid. 440 * If all the netconfig db has been read and placed into the list and 441 * there is no match for the netid, return NULL. 442 */ 443 if (ni.head != NULL) { 444 for (list = ni.head; list; list = list->next) { 445 if (strcmp(list->ncp->nc_netid, netid) == 0) 446 return(dup_ncp(list->ncp)); 447 } 448 if (ni.eof == 1) /* that's all the entries */ 449 return(NULL); 450 } 451 452 if ((file = fopen(NETCONFIG, "r")) == NULL) 453 return (NULL); 454 455 if ((linep = malloc(MAXNETCONFIGLINE)) == NULL) { 456 fclose(file); 457 return (NULL); 458 } 459 do { 460 ptrdiff_t len; 461 char *tmpp; /* tmp string pointer */ 462 463 do { 464 if ((stringp = fgets(linep, MAXNETCONFIGLINE, file)) 465 == NULL) 466 break; 467 } while (*stringp == '#'); 468 if (stringp == NULL) /* eof */ 469 break; 470 if ((tmpp = strpbrk(stringp, "\t ")) == NULL) { 471 /* can't parse file */ 472 nc_error = NC_BADFILE; 473 break; 474 } 475 if (strlen(netid) == (size_t) (len = tmpp - stringp) && /* a match */ 476 strncmp(stringp, netid, (size_t)len) == 0) { 477 if ((ncp = malloc(sizeof(*ncp))) == NULL) 478 break; 479 ncp->nc_lookups = NULL; 480 if (parse_ncp(linep, ncp) == -1) { 481 free(ncp); 482 ncp = NULL; 483 } 484 break; 485 } 486 } while (stringp != NULL); 487 if (ncp == NULL) 488 free(linep); 489 fclose(file); 490 return(ncp); 491 } 492 493 /* 494 * freenetconfigent(netconfigp) frees the netconfig structure pointed to by 495 * netconfigp (previously returned by getnetconfigent()). 496 */ 497 498 void 499 freenetconfigent(struct netconfig *netconfigp) 500 { 501 if (netconfigp != NULL) { 502 /* holds all netconfigp's strings */ 503 free(netconfigp->nc_netid); 504 if (netconfigp->nc_lookups != NULL) 505 free(netconfigp->nc_lookups); 506 free(netconfigp); 507 } 508 } 509 510 /* 511 * Parse line and stuff it in a struct netconfig 512 * Typical line might look like: 513 * udp tpi_cots vb inet udp /dev/udp /usr/lib/ip.so,/usr/local/ip.so 514 * 515 * We return -1 if any of the tokens don't parse, or malloc fails. 516 * 517 * Note that we modify stringp (putting NULLs after tokens) and 518 * we set the ncp's string field pointers to point to these tokens within 519 * stringp. 520 */ 521 522 static int 523 parse_ncp( 524 char *stringp, /* string to parse */ 525 struct netconfig *ncp) /* where to put results */ 526 { 527 char *tokenp; /* for processing tokens */ 528 char *lasts; 529 530 _DIAGASSERT(stringp != NULL); 531 _DIAGASSERT(ncp != NULL); 532 533 nc_error = NC_BADFILE; 534 /* nearly anything that breaks is for this reason */ 535 stringp[strlen(stringp)-1] = '\0'; /* get rid of newline */ 536 /* netid */ 537 if ((ncp->nc_netid = strtok_r(stringp, "\t ", &lasts)) == NULL) 538 return (-1); 539 540 /* semantics */ 541 if ((tokenp = strtok_r(NULL, "\t ", &lasts)) == NULL) 542 return (-1); 543 if (strcmp(tokenp, NC_TPI_COTS_ORD_S) == 0) 544 ncp->nc_semantics = NC_TPI_COTS_ORD; 545 else if (strcmp(tokenp, NC_TPI_COTS_S) == 0) 546 ncp->nc_semantics = NC_TPI_COTS; 547 else if (strcmp(tokenp, NC_TPI_CLTS_S) == 0) 548 ncp->nc_semantics = NC_TPI_CLTS; 549 else if (strcmp(tokenp, NC_TPI_RAW_S) == 0) 550 ncp->nc_semantics = NC_TPI_RAW; 551 else 552 return (-1); 553 554 /* flags */ 555 if ((tokenp = strtok_r(NULL, "\t ", &lasts)) == NULL) 556 return (-1); 557 for (ncp->nc_flag = NC_NOFLAG; *tokenp != '\0'; tokenp++) { 558 switch (*tokenp) { 559 case NC_NOFLAG_C: 560 break; 561 case NC_VISIBLE_C: 562 ncp->nc_flag |= NC_VISIBLE; 563 break; 564 case NC_BROADCAST_C: 565 ncp->nc_flag |= NC_BROADCAST; 566 break; 567 default: 568 return (-1); 569 } 570 } 571 /* protocol family */ 572 if ((ncp->nc_protofmly = strtok_r(NULL, "\t ", &lasts)) == NULL) 573 return (-1); 574 /* protocol name */ 575 if ((ncp->nc_proto = strtok_r(NULL, "\t ", &lasts)) == NULL) 576 return (-1); 577 /* network device */ 578 if ((ncp->nc_device = strtok_r(NULL, "\t ", &lasts)) == NULL) 579 return (-1); 580 if ((tokenp = strtok_r(NULL, "\t ", &lasts)) == NULL) 581 return (-1); 582 if (strcmp(tokenp, NC_NOLOOKUP) == 0) { 583 ncp->nc_nlookups = 0; 584 ncp->nc_lookups = NULL; 585 } else { 586 char *cp; /* tmp string */ 587 588 if (ncp->nc_lookups != NULL) /* from last visit */ 589 free(ncp->nc_lookups); 590 /* preallocate one string pointer */ 591 ncp->nc_lookups = malloc(sizeof(*ncp->nc_lookups)); 592 ncp->nc_nlookups = 0; 593 while ((cp = tokenp) != NULL) { 594 tokenp = _get_next_token(cp, ','); 595 ncp->nc_lookups[(size_t)ncp->nc_nlookups++] = cp; 596 ncp->nc_lookups = (char **) 597 realloc(ncp->nc_lookups, 598 (size_t)(ncp->nc_nlookups+1) *sizeof(char *)); 599 /* for next loop */ 600 } 601 } 602 return (0); 603 } 604 605 /* 606 * Returns a string describing the reason for failure. 607 */ 608 char * 609 nc_sperror(void) 610 { 611 const char *message; 612 613 switch(nc_error) { 614 case NC_NONETCONFIG: 615 message = _nc_errors[0]; 616 break; 617 case NC_NOMEM: 618 message = _nc_errors[1]; 619 break; 620 case NC_NOTINIT: 621 message = _nc_errors[2]; 622 break; 623 case NC_BADFILE: 624 message = _nc_errors[3]; 625 break; 626 default: 627 message = "Unknown network selection error"; 628 } 629 return __UNCONST(message); 630 } 631 632 /* 633 * Prints a message onto standard error describing the reason for failure. 634 */ 635 void 636 nc_perror(const char *s) 637 { 638 639 _DIAGASSERT(s != NULL); 640 641 fprintf(stderr, "%s: %s", s, nc_sperror()); 642 } 643 644 /* 645 * Duplicates the matched netconfig buffer. 646 */ 647 static struct netconfig * 648 dup_ncp(struct netconfig *ncp) 649 { 650 struct netconfig *p; 651 char *tmp; 652 u_int i; 653 654 _DIAGASSERT(ncp != NULL); 655 656 if ((tmp = malloc(MAXNETCONFIGLINE)) == NULL) 657 return(NULL); 658 if ((p = malloc(sizeof(*p))) == NULL) { 659 free(tmp); 660 return(NULL); 661 } 662 /* 663 * First we dup all the data from matched netconfig buffer. Then we 664 * adjust some of the member pointer to a pre-allocated buffer where 665 * contains part of the data. 666 * To follow the convention used in parse_ncp(), we store all the 667 * necessary information in the pre-allocated buffer and let each 668 * of the netconfig char pointer member point to the right address 669 * in the buffer. 670 */ 671 *p = *ncp; 672 p->nc_netid = (char *)strcpy(tmp,ncp->nc_netid); 673 tmp = strchr(tmp, '\0') + 1; 674 p->nc_protofmly = (char *)strcpy(tmp,ncp->nc_protofmly); 675 tmp = strchr(tmp, '\0') + 1; 676 p->nc_proto = (char *)strcpy(tmp,ncp->nc_proto); 677 tmp = strchr(tmp, '\0') + 1; 678 p->nc_device = (char *)strcpy(tmp,ncp->nc_device); 679 p->nc_lookups = malloc((size_t)(p->nc_nlookups+1) * sizeof(char *)); 680 if (p->nc_lookups == NULL) { 681 free(p->nc_netid); 682 free(p); 683 return(NULL); 684 } 685 for (i=0; i < p->nc_nlookups; i++) { 686 tmp = strchr(tmp, '\0') + 1; 687 p->nc_lookups[i] = strcpy(tmp,ncp->nc_lookups[i]); 688 } 689 return(p); 690 } 691