1 /* $NetBSD: npf.c,v 1.8 2012/04/01 19:16:24 rmind Exp $ */ 2 3 /*- 4 * Copyright (c) 2010-2012 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This material is based upon work partially supported by The 8 * NetBSD Foundation under a contract with Mindaugas Rasiukevicius. 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: npf.c,v 1.8 2012/04/01 19:16:24 rmind Exp $"); 34 35 #include <sys/types.h> 36 #include <netinet/in_systm.h> 37 #include <netinet/in.h> 38 #include <prop/proplib.h> 39 40 #include <stdlib.h> 41 #include <string.h> 42 #include <assert.h> 43 #include <errno.h> 44 #include <err.h> 45 46 #define _NPF_PRIVATE 47 #include "npf.h" 48 49 struct nl_config { 50 /* Rules, translations, tables, procedures. */ 51 prop_dictionary_t ncf_dict; 52 prop_array_t ncf_rules_list; 53 prop_array_t ncf_rproc_list; 54 prop_array_t ncf_table_list; 55 prop_array_t ncf_nat_list; 56 /* Priority counters. */ 57 pri_t ncf_rule_pri; 58 pri_t ncf_nat_pri; 59 /* Error report. */ 60 prop_dictionary_t ncf_err; 61 /* Custom file to externalise property-list. */ 62 const char * ncf_plist; 63 bool ncf_flush; 64 }; 65 66 struct nl_rule { 67 prop_dictionary_t nrl_dict; 68 }; 69 70 struct nl_rproc { 71 prop_dictionary_t nrp_dict; 72 }; 73 74 struct nl_table { 75 prop_dictionary_t ntl_dict; 76 }; 77 78 /* 79 * CONFIGURATION INTERFACE. 80 */ 81 82 nl_config_t * 83 npf_config_create(void) 84 { 85 nl_config_t *ncf; 86 87 ncf = calloc(1, sizeof(*ncf)); 88 if (ncf == NULL) { 89 return NULL; 90 } 91 ncf->ncf_rules_list = prop_array_create(); 92 ncf->ncf_rproc_list = prop_array_create(); 93 ncf->ncf_table_list = prop_array_create(); 94 ncf->ncf_nat_list = prop_array_create(); 95 96 ncf->ncf_rule_pri = 1; 97 ncf->ncf_nat_pri = 1; 98 99 ncf->ncf_plist = NULL; 100 ncf->ncf_flush = false; 101 102 return ncf; 103 } 104 105 int 106 npf_config_submit(nl_config_t *ncf, int fd) 107 { 108 const char *plist = ncf->ncf_plist; 109 prop_dictionary_t npf_dict; 110 int error = 0; 111 112 npf_dict = prop_dictionary_create(); 113 if (npf_dict == NULL) { 114 return ENOMEM; 115 } 116 prop_dictionary_set(npf_dict, "rules", ncf->ncf_rules_list); 117 prop_dictionary_set(npf_dict, "rprocs", ncf->ncf_rproc_list); 118 prop_dictionary_set(npf_dict, "tables", ncf->ncf_table_list); 119 prop_dictionary_set(npf_dict, "translation", ncf->ncf_nat_list); 120 prop_dictionary_set_bool(npf_dict, "flush", ncf->ncf_flush); 121 122 if (plist) { 123 if (!prop_dictionary_externalize_to_file(npf_dict, plist)) { 124 error = errno; 125 } 126 prop_object_release(npf_dict); 127 return error; 128 } 129 130 error = prop_dictionary_sendrecv_ioctl(npf_dict, fd, 131 IOC_NPF_RELOAD, &ncf->ncf_err); 132 if (error) { 133 prop_object_release(npf_dict); 134 assert(ncf->ncf_err == NULL); 135 return error; 136 } 137 138 prop_dictionary_get_int32(ncf->ncf_err, "errno", &error); 139 prop_object_release(npf_dict); 140 return error; 141 } 142 143 nl_config_t * 144 npf_config_retrieve(int fd, bool *active, bool *loaded) 145 { 146 prop_dictionary_t npf_dict; 147 nl_config_t *ncf; 148 int error; 149 150 error = prop_dictionary_recv_ioctl(fd, IOC_NPF_GETCONF, &npf_dict); 151 if (error) { 152 return NULL; 153 } 154 ncf = calloc(1, sizeof(*ncf)); 155 if (ncf == NULL) { 156 prop_object_release(npf_dict); 157 return NULL; 158 } 159 ncf->ncf_dict = npf_dict; 160 ncf->ncf_rules_list = prop_dictionary_get(npf_dict, "rules"); 161 ncf->ncf_rproc_list = prop_dictionary_get(npf_dict, "rprocs"); 162 ncf->ncf_table_list = prop_dictionary_get(npf_dict, "tables"); 163 ncf->ncf_nat_list = prop_dictionary_get(npf_dict, "translation"); 164 165 prop_dictionary_get_bool(npf_dict, "active", active); 166 *loaded = (ncf->ncf_rules_list != NULL); 167 return ncf; 168 } 169 170 int 171 npf_config_flush(int fd) 172 { 173 nl_config_t *ncf; 174 int error; 175 176 ncf = npf_config_create(); 177 if (ncf == NULL) { 178 return ENOMEM; 179 } 180 ncf->ncf_flush = true; 181 error = npf_config_submit(ncf, fd); 182 npf_config_destroy(ncf); 183 return error; 184 } 185 186 void 187 _npf_config_error(nl_config_t *ncf, nl_error_t *ne) 188 { 189 memset(ne, 0, sizeof(*ne)); 190 prop_dictionary_get_int32(ncf->ncf_err, "id", &ne->ne_id); 191 prop_dictionary_get_cstring(ncf->ncf_err, 192 "source-file", &ne->ne_source_file); 193 prop_dictionary_get_uint32(ncf->ncf_err, 194 "source-line", &ne->ne_source_line); 195 prop_dictionary_get_int32(ncf->ncf_err, 196 "ncode-error", &ne->ne_ncode_error); 197 prop_dictionary_get_int32(ncf->ncf_err, 198 "ncode-errat", &ne->ne_ncode_errat); 199 } 200 201 void 202 npf_config_destroy(nl_config_t *ncf) 203 { 204 205 if (ncf->ncf_dict == NULL) { 206 prop_object_release(ncf->ncf_rules_list); 207 prop_object_release(ncf->ncf_rproc_list); 208 prop_object_release(ncf->ncf_table_list); 209 prop_object_release(ncf->ncf_nat_list); 210 } else { 211 prop_object_release(ncf->ncf_dict); 212 } 213 if (ncf->ncf_err) { 214 prop_object_release(ncf->ncf_err); 215 } 216 free(ncf); 217 } 218 219 void 220 _npf_config_setsubmit(nl_config_t *ncf, const char *plist_file) 221 { 222 223 ncf->ncf_plist = plist_file; 224 } 225 226 static bool 227 _npf_prop_array_lookup(prop_array_t array, const char *key, const char *name) 228 { 229 prop_dictionary_t dict; 230 prop_object_iterator_t it; 231 232 it = prop_array_iterator(array); 233 while ((dict = prop_object_iterator_next(it)) != NULL) { 234 const char *lname; 235 prop_dictionary_get_cstring_nocopy(dict, key, &lname); 236 if (strcmp(name, lname) == 0) 237 break; 238 } 239 prop_object_iterator_release(it); 240 return dict ? true : false; 241 } 242 243 /* 244 * RULE INTERFACE. 245 */ 246 247 nl_rule_t * 248 npf_rule_create(const char *name, uint32_t attr, u_int if_idx) 249 { 250 prop_dictionary_t rldict; 251 nl_rule_t *rl; 252 253 rl = malloc(sizeof(*rl)); 254 if (rl == NULL) { 255 return NULL; 256 } 257 rldict = prop_dictionary_create(); 258 if (rldict == NULL) { 259 free(rl); 260 return NULL; 261 } 262 if (name) { 263 prop_dictionary_set_cstring(rldict, "name", name); 264 } 265 prop_dictionary_set_uint32(rldict, "attributes", attr); 266 267 if (if_idx) { 268 prop_dictionary_set_uint32(rldict, "interface", if_idx); 269 } 270 rl->nrl_dict = rldict; 271 return rl; 272 } 273 274 int 275 npf_rule_setcode(nl_rule_t *rl, int type, const void *code, size_t sz) 276 { 277 prop_dictionary_t rldict = rl->nrl_dict; 278 prop_data_t cdata; 279 280 if (type != NPF_CODE_NCODE) { 281 return ENOTSUP; 282 } 283 cdata = prop_data_create_data(code, sz); 284 if (cdata == NULL) { 285 return ENOMEM; 286 } 287 prop_dictionary_set(rldict, "ncode", cdata); 288 prop_object_release(cdata); 289 return 0; 290 } 291 292 int 293 npf_rule_setproc(nl_config_t *ncf, nl_rule_t *rl, const char *name) 294 { 295 prop_dictionary_t rldict = rl->nrl_dict; 296 297 if (!npf_rproc_exists_p(ncf, name)) { 298 return ENOENT; 299 } 300 prop_dictionary_set_cstring(rldict, "rproc", name); 301 return 0; 302 } 303 304 bool 305 npf_rule_exists_p(nl_config_t *ncf, const char *name) 306 { 307 308 return _npf_prop_array_lookup(ncf->ncf_rules_list, "name", name); 309 } 310 311 int 312 npf_rule_insert(nl_config_t *ncf, nl_rule_t *parent, nl_rule_t *rl, pri_t pri) 313 { 314 prop_dictionary_t rldict = rl->nrl_dict; 315 prop_array_t rlset; 316 317 if (pri == NPF_PRI_NEXT) { 318 pri = ncf->ncf_rule_pri++; 319 } else if (ncf) { 320 ncf->ncf_rule_pri = pri + 1; 321 } 322 prop_dictionary_set_int32(rldict, "priority", pri); 323 324 if (parent) { 325 prop_dictionary_t pdict = parent->nrl_dict; 326 rlset = prop_dictionary_get(pdict, "subrules"); 327 if (rlset == NULL) { 328 rlset = prop_array_create(); 329 prop_dictionary_set(pdict, "subrules", rlset); 330 prop_object_release(rlset); 331 } 332 } else { 333 rlset = ncf->ncf_rules_list; 334 } 335 prop_array_add(rlset, rldict); 336 return 0; 337 } 338 339 static int 340 _npf_rule_foreach1(prop_array_t rules, unsigned nlevel, nl_rule_callback_t func) 341 { 342 prop_dictionary_t rldict; 343 prop_object_iterator_t it; 344 345 if (!rules || prop_object_type(rules) != PROP_TYPE_ARRAY) { 346 return ENOENT; 347 } 348 it = prop_array_iterator(rules); 349 if (it == NULL) { 350 return ENOMEM; 351 } 352 while ((rldict = prop_object_iterator_next(it)) != NULL) { 353 prop_array_t subrules; 354 nl_rule_t nrl; 355 356 nrl.nrl_dict = rldict; 357 (*func)(&nrl, nlevel); 358 359 subrules = prop_dictionary_get(rldict, "subrules"); 360 (void)_npf_rule_foreach1(subrules, nlevel + 1, func); 361 } 362 prop_object_iterator_release(it); 363 return 0; 364 } 365 366 int 367 _npf_rule_foreach(nl_config_t *ncf, nl_rule_callback_t func) 368 { 369 370 return _npf_rule_foreach1(ncf->ncf_rules_list, 0, func); 371 } 372 373 pri_t 374 _npf_rule_getinfo(nl_rule_t *nrl, const char **rname, uint32_t *attr, 375 u_int *if_idx) 376 { 377 prop_dictionary_t rldict = nrl->nrl_dict; 378 pri_t prio; 379 380 prop_dictionary_get_cstring_nocopy(rldict, "name", rname); 381 prop_dictionary_get_uint32(rldict, "attributes", attr); 382 prop_dictionary_get_int32(rldict, "priority", &prio); 383 prop_dictionary_get_uint32(rldict, "interface", if_idx); 384 return prio; 385 } 386 387 const void * 388 _npf_rule_ncode(nl_rule_t *nrl, size_t *size) 389 { 390 prop_dictionary_t rldict = nrl->nrl_dict; 391 prop_object_t obj = prop_dictionary_get(rldict, "ncode"); 392 *size = prop_data_size(obj); 393 return prop_data_data_nocopy(obj); 394 } 395 396 const char * 397 _npf_rule_rproc(nl_rule_t *nrl) 398 { 399 prop_dictionary_t rldict = nrl->nrl_dict; 400 const char *rpname = NULL; 401 402 prop_dictionary_get_cstring_nocopy(rldict, "rproc", &rpname); 403 return rpname; 404 } 405 406 void 407 npf_rule_destroy(nl_rule_t *rl) 408 { 409 410 prop_object_release(rl->nrl_dict); 411 free(rl); 412 } 413 414 /* 415 * RULE PROCEDURE INTERFACE. 416 */ 417 418 nl_rproc_t * 419 npf_rproc_create(const char *name) 420 { 421 prop_dictionary_t rpdict; 422 nl_rproc_t *nrp; 423 424 nrp = malloc(sizeof(nl_rproc_t)); 425 if (nrp == NULL) { 426 return NULL; 427 } 428 rpdict = prop_dictionary_create(); 429 if (rpdict == NULL) { 430 free(nrp); 431 return NULL; 432 } 433 prop_dictionary_set_cstring(rpdict, "name", name); 434 nrp->nrp_dict = rpdict; 435 return nrp; 436 } 437 438 bool 439 npf_rproc_exists_p(nl_config_t *ncf, const char *name) 440 { 441 442 return _npf_prop_array_lookup(ncf->ncf_rproc_list, "name", name); 443 } 444 445 int 446 _npf_rproc_setnorm(nl_rproc_t *rp, bool rnd, bool no_df, u_int minttl, 447 u_int maxmss) 448 { 449 prop_dictionary_t rpdict = rp->nrp_dict; 450 uint32_t fl; 451 452 prop_dictionary_set_bool(rpdict, "randomize-id", rnd); 453 prop_dictionary_set_bool(rpdict, "no-df", no_df); 454 prop_dictionary_set_uint32(rpdict, "min-ttl", minttl); 455 prop_dictionary_set_uint32(rpdict, "max-mss", maxmss); 456 457 prop_dictionary_get_uint32(rpdict, "flags", &fl); 458 prop_dictionary_set_uint32(rpdict, "flags", fl | NPF_RPROC_NORMALIZE); 459 return 0; 460 } 461 462 int 463 _npf_rproc_setlog(nl_rproc_t *rp, u_int if_idx) 464 { 465 prop_dictionary_t rpdict = rp->nrp_dict; 466 uint32_t fl; 467 468 prop_dictionary_set_uint32(rpdict, "log-interface", if_idx); 469 470 prop_dictionary_get_uint32(rpdict, "flags", &fl); 471 prop_dictionary_set_uint32(rpdict, "flags", fl | NPF_RPROC_LOG); 472 return 0; 473 } 474 475 int 476 npf_rproc_insert(nl_config_t *ncf, nl_rproc_t *rp) 477 { 478 prop_dictionary_t rpdict = rp->nrp_dict; 479 const char *name; 480 481 if (!prop_dictionary_get_cstring_nocopy(rpdict, "name", &name)) { 482 return EINVAL; 483 } 484 if (npf_rproc_exists_p(ncf, name)) { 485 return EEXIST; 486 } 487 prop_array_add(ncf->ncf_rproc_list, rpdict); 488 return 0; 489 } 490 491 /* 492 * TRANSLATION INTERFACE. 493 */ 494 495 nl_nat_t * 496 npf_nat_create(int type, u_int flags, u_int if_idx, 497 npf_addr_t *addr, int af, in_port_t port) 498 { 499 nl_rule_t *rl; 500 prop_dictionary_t rldict; 501 prop_data_t addrdat; 502 uint32_t attr; 503 size_t sz; 504 505 if (af == AF_INET) { 506 sz = sizeof(struct in_addr); 507 } else if (af == AF_INET6) { 508 sz = sizeof(struct in6_addr); 509 } else { 510 return NULL; 511 } 512 513 attr = NPF_RULE_PASS | NPF_RULE_FINAL | 514 (type == NPF_NATOUT ? NPF_RULE_OUT : NPF_RULE_IN); 515 516 /* Create a rule for NAT policy. Next, will add translation data. */ 517 rl = npf_rule_create(NULL, attr, if_idx); 518 if (rl == NULL) { 519 return NULL; 520 } 521 rldict = rl->nrl_dict; 522 523 /* Translation type and flags. */ 524 prop_dictionary_set_int32(rldict, "type", type); 525 prop_dictionary_set_uint32(rldict, "flags", flags); 526 527 /* Translation IP. */ 528 addrdat = prop_data_create_data(addr, sz); 529 if (addrdat == NULL) { 530 npf_rule_destroy(rl); 531 return NULL; 532 } 533 prop_dictionary_set(rldict, "translation-ip", addrdat); 534 prop_object_release(addrdat); 535 536 /* Translation port (for redirect case). */ 537 prop_dictionary_set_uint16(rldict, "translation-port", port); 538 539 return (nl_nat_t *)rl; 540 } 541 542 int 543 npf_nat_insert(nl_config_t *ncf, nl_nat_t *nt, pri_t pri) 544 { 545 prop_dictionary_t rldict = nt->nrl_dict; 546 547 if (pri == NPF_PRI_NEXT) { 548 pri = ncf->ncf_nat_pri++; 549 } else { 550 ncf->ncf_nat_pri = pri + 1; 551 } 552 prop_dictionary_set_int32(rldict, "priority", pri); 553 prop_array_add(ncf->ncf_nat_list, rldict); 554 return 0; 555 } 556 557 /* 558 * TABLE INTERFACE. 559 */ 560 561 nl_table_t * 562 npf_table_create(u_int id, int type) 563 { 564 prop_dictionary_t tldict; 565 prop_array_t tblents; 566 nl_table_t *tl; 567 568 tl = malloc(sizeof(*tl)); 569 if (tl == NULL) { 570 return NULL; 571 } 572 tldict = prop_dictionary_create(); 573 if (tldict == NULL) { 574 free(tl); 575 return NULL; 576 } 577 prop_dictionary_set_uint32(tldict, "id", id); 578 prop_dictionary_set_int32(tldict, "type", type); 579 580 tblents = prop_array_create(); 581 if (tblents == NULL) { 582 prop_object_release(tldict); 583 free(tl); 584 return NULL; 585 } 586 prop_dictionary_set(tldict, "entries", tblents); 587 prop_object_release(tblents); 588 589 tl->ntl_dict = tldict; 590 return tl; 591 } 592 593 int 594 npf_table_add_entry(nl_table_t *tl, npf_addr_t *addr, npf_netmask_t mask) 595 { 596 prop_dictionary_t tldict = tl->ntl_dict, entdict; 597 prop_array_t tblents; 598 prop_data_t addrdata; 599 600 /* Create the table entry. */ 601 entdict = prop_dictionary_create(); 602 if (entdict) { 603 return ENOMEM; 604 } 605 addrdata = prop_data_create_data(addr, sizeof(npf_addr_t)); 606 prop_dictionary_set(entdict, "addr", addrdata); 607 prop_dictionary_set_uint8(entdict, "mask", mask); 608 prop_object_release(addrdata); 609 610 /* Insert the entry. */ 611 tblents = prop_dictionary_get(tldict, "entries"); 612 prop_array_add(tblents, entdict); 613 prop_object_release(entdict); 614 return 0; 615 } 616 617 bool 618 npf_table_exists_p(nl_config_t *ncf, u_int tid) 619 { 620 prop_dictionary_t tldict; 621 prop_object_iterator_t it; 622 623 it = prop_array_iterator(ncf->ncf_table_list); 624 while ((tldict = prop_object_iterator_next(it)) != NULL) { 625 u_int i; 626 if (prop_dictionary_get_uint32(tldict, "id", &i) && tid == i) 627 break; 628 } 629 prop_object_iterator_release(it); 630 return tldict ? true : false; 631 } 632 633 int 634 npf_table_insert(nl_config_t *ncf, nl_table_t *tl) 635 { 636 prop_dictionary_t tldict = tl->ntl_dict; 637 u_int tid; 638 639 if (!prop_dictionary_get_uint32(tldict, "id", &tid)) { 640 return EINVAL; 641 } 642 if (npf_table_exists_p(ncf, tid)) { 643 return EEXIST; 644 } 645 prop_array_add(ncf->ncf_table_list, tldict); 646 return 0; 647 } 648 649 void 650 npf_table_destroy(nl_table_t *tl) 651 { 652 653 prop_object_release(tl->ntl_dict); 654 free(tl); 655 } 656 657 /* 658 * MISC. 659 */ 660 661 int 662 npf_update_rule(int fd, const char *rname __unused, nl_rule_t *rl) 663 { 664 prop_dictionary_t rldict = rl->nrl_dict, errdict = NULL; 665 int error; 666 667 error = prop_dictionary_sendrecv_ioctl(rldict, fd, 668 IOC_NPF_UPDATE_RULE, &errdict); 669 if (errdict) { 670 prop_object_release(errdict); 671 } 672 return error; 673 } 674 675 int 676 npf_sessions_recv(int fd, const char *fpath) 677 { 678 prop_dictionary_t sdict; 679 int error; 680 681 error = prop_dictionary_recv_ioctl(fd, IOC_NPF_SESSIONS_SAVE, &sdict); 682 if (error) { 683 return error; 684 } 685 if (!prop_dictionary_externalize_to_file(sdict, fpath)) { 686 error = errno; 687 } 688 prop_object_release(sdict); 689 return error; 690 } 691 692 int 693 npf_sessions_send(int fd, const char *fpath) 694 { 695 prop_dictionary_t sdict; 696 int error; 697 698 if (fpath) { 699 sdict = prop_dictionary_internalize_from_file(fpath); 700 if (sdict == NULL) { 701 return errno; 702 } 703 } else { 704 /* Empty: will flush the sessions. */ 705 prop_array_t selist = prop_array_create(); 706 sdict = prop_dictionary_create(); 707 prop_dictionary_set(sdict, "session-list", selist); 708 prop_object_release(selist); 709 } 710 error = prop_dictionary_send_ioctl(sdict, fd, IOC_NPF_SESSIONS_LOAD); 711 prop_object_release(sdict); 712 return error; 713 } 714