1 /* 2 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> 3 * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * Development of this code funded by Astaro AG (http://www.astaro.com/) 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/init.h> 14 #include <linux/module.h> 15 #include <linux/netlink.h> 16 #include <linux/netfilter.h> 17 #include <linux/netfilter/nf_tables.h> 18 #include <net/netfilter/nf_tables.h> 19 #include <net/netfilter/nf_conntrack.h> 20 #include <net/netfilter/nf_conntrack_acct.h> 21 #include <net/netfilter/nf_conntrack_tuple.h> 22 #include <net/netfilter/nf_conntrack_helper.h> 23 #include <net/netfilter/nf_conntrack_ecache.h> 24 #include <net/netfilter/nf_conntrack_labels.h> 25 26 struct nft_ct { 27 enum nft_ct_keys key:8; 28 enum ip_conntrack_dir dir:8; 29 union { 30 enum nft_registers dreg:8; 31 enum nft_registers sreg:8; 32 }; 33 }; 34 35 struct nft_ct_helper_obj { 36 struct nf_conntrack_helper *helper4; 37 struct nf_conntrack_helper *helper6; 38 u8 l4proto; 39 }; 40 41 #ifdef CONFIG_NF_CONNTRACK_ZONES 42 static DEFINE_PER_CPU(struct nf_conn *, nft_ct_pcpu_template); 43 static unsigned int nft_ct_pcpu_template_refcnt __read_mostly; 44 #endif 45 46 static u64 nft_ct_get_eval_counter(const struct nf_conn_counter *c, 47 enum nft_ct_keys k, 48 enum ip_conntrack_dir d) 49 { 50 if (d < IP_CT_DIR_MAX) 51 return k == NFT_CT_BYTES ? atomic64_read(&c[d].bytes) : 52 atomic64_read(&c[d].packets); 53 54 return nft_ct_get_eval_counter(c, k, IP_CT_DIR_ORIGINAL) + 55 nft_ct_get_eval_counter(c, k, IP_CT_DIR_REPLY); 56 } 57 58 static void nft_ct_get_eval(const struct nft_expr *expr, 59 struct nft_regs *regs, 60 const struct nft_pktinfo *pkt) 61 { 62 const struct nft_ct *priv = nft_expr_priv(expr); 63 u32 *dest = ®s->data[priv->dreg]; 64 enum ip_conntrack_info ctinfo; 65 const struct nf_conn *ct; 66 const struct nf_conn_help *help; 67 const struct nf_conntrack_tuple *tuple; 68 const struct nf_conntrack_helper *helper; 69 unsigned int state; 70 71 ct = nf_ct_get(pkt->skb, &ctinfo); 72 73 switch (priv->key) { 74 case NFT_CT_STATE: 75 if (ct) 76 state = NF_CT_STATE_BIT(ctinfo); 77 else if (ctinfo == IP_CT_UNTRACKED) 78 state = NF_CT_STATE_UNTRACKED_BIT; 79 else 80 state = NF_CT_STATE_INVALID_BIT; 81 *dest = state; 82 return; 83 default: 84 break; 85 } 86 87 if (ct == NULL) 88 goto err; 89 90 switch (priv->key) { 91 case NFT_CT_DIRECTION: 92 nft_reg_store8(dest, CTINFO2DIR(ctinfo)); 93 return; 94 case NFT_CT_STATUS: 95 *dest = ct->status; 96 return; 97 #ifdef CONFIG_NF_CONNTRACK_MARK 98 case NFT_CT_MARK: 99 *dest = ct->mark; 100 return; 101 #endif 102 #ifdef CONFIG_NF_CONNTRACK_SECMARK 103 case NFT_CT_SECMARK: 104 *dest = ct->secmark; 105 return; 106 #endif 107 case NFT_CT_EXPIRATION: 108 *dest = jiffies_to_msecs(nf_ct_expires(ct)); 109 return; 110 case NFT_CT_HELPER: 111 if (ct->master == NULL) 112 goto err; 113 help = nfct_help(ct->master); 114 if (help == NULL) 115 goto err; 116 helper = rcu_dereference(help->helper); 117 if (helper == NULL) 118 goto err; 119 strncpy((char *)dest, helper->name, NF_CT_HELPER_NAME_LEN); 120 return; 121 #ifdef CONFIG_NF_CONNTRACK_LABELS 122 case NFT_CT_LABELS: { 123 struct nf_conn_labels *labels = nf_ct_labels_find(ct); 124 125 if (labels) 126 memcpy(dest, labels->bits, NF_CT_LABELS_MAX_SIZE); 127 else 128 memset(dest, 0, NF_CT_LABELS_MAX_SIZE); 129 return; 130 } 131 #endif 132 case NFT_CT_BYTES: /* fallthrough */ 133 case NFT_CT_PKTS: { 134 const struct nf_conn_acct *acct = nf_conn_acct_find(ct); 135 u64 count = 0; 136 137 if (acct) 138 count = nft_ct_get_eval_counter(acct->counter, 139 priv->key, priv->dir); 140 memcpy(dest, &count, sizeof(count)); 141 return; 142 } 143 case NFT_CT_AVGPKT: { 144 const struct nf_conn_acct *acct = nf_conn_acct_find(ct); 145 u64 avgcnt = 0, bcnt = 0, pcnt = 0; 146 147 if (acct) { 148 pcnt = nft_ct_get_eval_counter(acct->counter, 149 NFT_CT_PKTS, priv->dir); 150 bcnt = nft_ct_get_eval_counter(acct->counter, 151 NFT_CT_BYTES, priv->dir); 152 if (pcnt != 0) 153 avgcnt = div64_u64(bcnt, pcnt); 154 } 155 156 memcpy(dest, &avgcnt, sizeof(avgcnt)); 157 return; 158 } 159 case NFT_CT_L3PROTOCOL: 160 nft_reg_store8(dest, nf_ct_l3num(ct)); 161 return; 162 case NFT_CT_PROTOCOL: 163 nft_reg_store8(dest, nf_ct_protonum(ct)); 164 return; 165 #ifdef CONFIG_NF_CONNTRACK_ZONES 166 case NFT_CT_ZONE: { 167 const struct nf_conntrack_zone *zone = nf_ct_zone(ct); 168 u16 zoneid; 169 170 if (priv->dir < IP_CT_DIR_MAX) 171 zoneid = nf_ct_zone_id(zone, priv->dir); 172 else 173 zoneid = zone->id; 174 175 nft_reg_store16(dest, zoneid); 176 return; 177 } 178 #endif 179 default: 180 break; 181 } 182 183 tuple = &ct->tuplehash[priv->dir].tuple; 184 switch (priv->key) { 185 case NFT_CT_SRC: 186 memcpy(dest, tuple->src.u3.all, 187 nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16); 188 return; 189 case NFT_CT_DST: 190 memcpy(dest, tuple->dst.u3.all, 191 nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16); 192 return; 193 case NFT_CT_PROTO_SRC: 194 nft_reg_store16(dest, (__force u16)tuple->src.u.all); 195 return; 196 case NFT_CT_PROTO_DST: 197 nft_reg_store16(dest, (__force u16)tuple->dst.u.all); 198 return; 199 default: 200 break; 201 } 202 return; 203 err: 204 regs->verdict.code = NFT_BREAK; 205 } 206 207 #ifdef CONFIG_NF_CONNTRACK_ZONES 208 static void nft_ct_set_zone_eval(const struct nft_expr *expr, 209 struct nft_regs *regs, 210 const struct nft_pktinfo *pkt) 211 { 212 struct nf_conntrack_zone zone = { .dir = NF_CT_DEFAULT_ZONE_DIR }; 213 const struct nft_ct *priv = nft_expr_priv(expr); 214 struct sk_buff *skb = pkt->skb; 215 enum ip_conntrack_info ctinfo; 216 u16 value = nft_reg_load16(®s->data[priv->sreg]); 217 struct nf_conn *ct; 218 219 ct = nf_ct_get(skb, &ctinfo); 220 if (ct) /* already tracked */ 221 return; 222 223 zone.id = value; 224 225 switch (priv->dir) { 226 case IP_CT_DIR_ORIGINAL: 227 zone.dir = NF_CT_ZONE_DIR_ORIG; 228 break; 229 case IP_CT_DIR_REPLY: 230 zone.dir = NF_CT_ZONE_DIR_REPL; 231 break; 232 default: 233 break; 234 } 235 236 ct = this_cpu_read(nft_ct_pcpu_template); 237 238 if (likely(atomic_read(&ct->ct_general.use) == 1)) { 239 nf_ct_zone_add(ct, &zone); 240 } else { 241 /* previous skb got queued to userspace */ 242 ct = nf_ct_tmpl_alloc(nft_net(pkt), &zone, GFP_ATOMIC); 243 if (!ct) { 244 regs->verdict.code = NF_DROP; 245 return; 246 } 247 } 248 249 atomic_inc(&ct->ct_general.use); 250 nf_ct_set(skb, ct, IP_CT_NEW); 251 } 252 #endif 253 254 static void nft_ct_set_eval(const struct nft_expr *expr, 255 struct nft_regs *regs, 256 const struct nft_pktinfo *pkt) 257 { 258 const struct nft_ct *priv = nft_expr_priv(expr); 259 struct sk_buff *skb = pkt->skb; 260 #ifdef CONFIG_NF_CONNTRACK_MARK 261 u32 value = regs->data[priv->sreg]; 262 #endif 263 enum ip_conntrack_info ctinfo; 264 struct nf_conn *ct; 265 266 ct = nf_ct_get(skb, &ctinfo); 267 if (ct == NULL || nf_ct_is_template(ct)) 268 return; 269 270 switch (priv->key) { 271 #ifdef CONFIG_NF_CONNTRACK_MARK 272 case NFT_CT_MARK: 273 if (ct->mark != value) { 274 ct->mark = value; 275 nf_conntrack_event_cache(IPCT_MARK, ct); 276 } 277 break; 278 #endif 279 #ifdef CONFIG_NF_CONNTRACK_LABELS 280 case NFT_CT_LABELS: 281 nf_connlabels_replace(ct, 282 ®s->data[priv->sreg], 283 ®s->data[priv->sreg], 284 NF_CT_LABELS_MAX_SIZE / sizeof(u32)); 285 break; 286 #endif 287 #ifdef CONFIG_NF_CONNTRACK_EVENTS 288 case NFT_CT_EVENTMASK: { 289 struct nf_conntrack_ecache *e = nf_ct_ecache_find(ct); 290 u32 ctmask = regs->data[priv->sreg]; 291 292 if (e) { 293 if (e->ctmask != ctmask) 294 e->ctmask = ctmask; 295 break; 296 } 297 298 if (ctmask && !nf_ct_is_confirmed(ct)) 299 nf_ct_ecache_ext_add(ct, ctmask, 0, GFP_ATOMIC); 300 break; 301 } 302 #endif 303 default: 304 break; 305 } 306 } 307 308 static const struct nla_policy nft_ct_policy[NFTA_CT_MAX + 1] = { 309 [NFTA_CT_DREG] = { .type = NLA_U32 }, 310 [NFTA_CT_KEY] = { .type = NLA_U32 }, 311 [NFTA_CT_DIRECTION] = { .type = NLA_U8 }, 312 [NFTA_CT_SREG] = { .type = NLA_U32 }, 313 }; 314 315 static int nft_ct_netns_get(struct net *net, uint8_t family) 316 { 317 int err; 318 319 if (family == NFPROTO_INET) { 320 err = nf_ct_netns_get(net, NFPROTO_IPV4); 321 if (err < 0) 322 goto err1; 323 err = nf_ct_netns_get(net, NFPROTO_IPV6); 324 if (err < 0) 325 goto err2; 326 } else { 327 err = nf_ct_netns_get(net, family); 328 if (err < 0) 329 goto err1; 330 } 331 return 0; 332 333 err2: 334 nf_ct_netns_put(net, NFPROTO_IPV4); 335 err1: 336 return err; 337 } 338 339 static void nft_ct_netns_put(struct net *net, uint8_t family) 340 { 341 if (family == NFPROTO_INET) { 342 nf_ct_netns_put(net, NFPROTO_IPV4); 343 nf_ct_netns_put(net, NFPROTO_IPV6); 344 } else 345 nf_ct_netns_put(net, family); 346 } 347 348 #ifdef CONFIG_NF_CONNTRACK_ZONES 349 static void nft_ct_tmpl_put_pcpu(void) 350 { 351 struct nf_conn *ct; 352 int cpu; 353 354 for_each_possible_cpu(cpu) { 355 ct = per_cpu(nft_ct_pcpu_template, cpu); 356 if (!ct) 357 break; 358 nf_ct_put(ct); 359 per_cpu(nft_ct_pcpu_template, cpu) = NULL; 360 } 361 } 362 363 static bool nft_ct_tmpl_alloc_pcpu(void) 364 { 365 struct nf_conntrack_zone zone = { .id = 0 }; 366 struct nf_conn *tmp; 367 int cpu; 368 369 if (nft_ct_pcpu_template_refcnt) 370 return true; 371 372 for_each_possible_cpu(cpu) { 373 tmp = nf_ct_tmpl_alloc(&init_net, &zone, GFP_KERNEL); 374 if (!tmp) { 375 nft_ct_tmpl_put_pcpu(); 376 return false; 377 } 378 379 atomic_set(&tmp->ct_general.use, 1); 380 per_cpu(nft_ct_pcpu_template, cpu) = tmp; 381 } 382 383 return true; 384 } 385 #endif 386 387 static int nft_ct_get_init(const struct nft_ctx *ctx, 388 const struct nft_expr *expr, 389 const struct nlattr * const tb[]) 390 { 391 struct nft_ct *priv = nft_expr_priv(expr); 392 unsigned int len; 393 int err; 394 395 priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY])); 396 priv->dir = IP_CT_DIR_MAX; 397 switch (priv->key) { 398 case NFT_CT_DIRECTION: 399 if (tb[NFTA_CT_DIRECTION] != NULL) 400 return -EINVAL; 401 len = sizeof(u8); 402 break; 403 case NFT_CT_STATE: 404 case NFT_CT_STATUS: 405 #ifdef CONFIG_NF_CONNTRACK_MARK 406 case NFT_CT_MARK: 407 #endif 408 #ifdef CONFIG_NF_CONNTRACK_SECMARK 409 case NFT_CT_SECMARK: 410 #endif 411 case NFT_CT_EXPIRATION: 412 if (tb[NFTA_CT_DIRECTION] != NULL) 413 return -EINVAL; 414 len = sizeof(u32); 415 break; 416 #ifdef CONFIG_NF_CONNTRACK_LABELS 417 case NFT_CT_LABELS: 418 if (tb[NFTA_CT_DIRECTION] != NULL) 419 return -EINVAL; 420 len = NF_CT_LABELS_MAX_SIZE; 421 break; 422 #endif 423 case NFT_CT_HELPER: 424 if (tb[NFTA_CT_DIRECTION] != NULL) 425 return -EINVAL; 426 len = NF_CT_HELPER_NAME_LEN; 427 break; 428 429 case NFT_CT_L3PROTOCOL: 430 case NFT_CT_PROTOCOL: 431 /* For compatibility, do not report error if NFTA_CT_DIRECTION 432 * attribute is specified. 433 */ 434 len = sizeof(u8); 435 break; 436 case NFT_CT_SRC: 437 case NFT_CT_DST: 438 if (tb[NFTA_CT_DIRECTION] == NULL) 439 return -EINVAL; 440 441 switch (ctx->afi->family) { 442 case NFPROTO_IPV4: 443 len = FIELD_SIZEOF(struct nf_conntrack_tuple, 444 src.u3.ip); 445 break; 446 case NFPROTO_IPV6: 447 case NFPROTO_INET: 448 len = FIELD_SIZEOF(struct nf_conntrack_tuple, 449 src.u3.ip6); 450 break; 451 default: 452 return -EAFNOSUPPORT; 453 } 454 break; 455 case NFT_CT_PROTO_SRC: 456 case NFT_CT_PROTO_DST: 457 if (tb[NFTA_CT_DIRECTION] == NULL) 458 return -EINVAL; 459 len = FIELD_SIZEOF(struct nf_conntrack_tuple, src.u.all); 460 break; 461 case NFT_CT_BYTES: 462 case NFT_CT_PKTS: 463 case NFT_CT_AVGPKT: 464 len = sizeof(u64); 465 break; 466 #ifdef CONFIG_NF_CONNTRACK_ZONES 467 case NFT_CT_ZONE: 468 len = sizeof(u16); 469 break; 470 #endif 471 default: 472 return -EOPNOTSUPP; 473 } 474 475 if (tb[NFTA_CT_DIRECTION] != NULL) { 476 priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]); 477 switch (priv->dir) { 478 case IP_CT_DIR_ORIGINAL: 479 case IP_CT_DIR_REPLY: 480 break; 481 default: 482 return -EINVAL; 483 } 484 } 485 486 priv->dreg = nft_parse_register(tb[NFTA_CT_DREG]); 487 err = nft_validate_register_store(ctx, priv->dreg, NULL, 488 NFT_DATA_VALUE, len); 489 if (err < 0) 490 return err; 491 492 err = nft_ct_netns_get(ctx->net, ctx->afi->family); 493 if (err < 0) 494 return err; 495 496 if (priv->key == NFT_CT_BYTES || 497 priv->key == NFT_CT_PKTS || 498 priv->key == NFT_CT_AVGPKT) 499 nf_ct_set_acct(ctx->net, true); 500 501 return 0; 502 } 503 504 static void __nft_ct_set_destroy(const struct nft_ctx *ctx, struct nft_ct *priv) 505 { 506 switch (priv->key) { 507 #ifdef CONFIG_NF_CONNTRACK_LABELS 508 case NFT_CT_LABELS: 509 nf_connlabels_put(ctx->net); 510 break; 511 #endif 512 #ifdef CONFIG_NF_CONNTRACK_ZONES 513 case NFT_CT_ZONE: 514 if (--nft_ct_pcpu_template_refcnt == 0) 515 nft_ct_tmpl_put_pcpu(); 516 #endif 517 default: 518 break; 519 } 520 } 521 522 static int nft_ct_set_init(const struct nft_ctx *ctx, 523 const struct nft_expr *expr, 524 const struct nlattr * const tb[]) 525 { 526 struct nft_ct *priv = nft_expr_priv(expr); 527 unsigned int len; 528 int err; 529 530 priv->dir = IP_CT_DIR_MAX; 531 priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY])); 532 switch (priv->key) { 533 #ifdef CONFIG_NF_CONNTRACK_MARK 534 case NFT_CT_MARK: 535 if (tb[NFTA_CT_DIRECTION]) 536 return -EINVAL; 537 len = FIELD_SIZEOF(struct nf_conn, mark); 538 break; 539 #endif 540 #ifdef CONFIG_NF_CONNTRACK_LABELS 541 case NFT_CT_LABELS: 542 if (tb[NFTA_CT_DIRECTION]) 543 return -EINVAL; 544 len = NF_CT_LABELS_MAX_SIZE; 545 err = nf_connlabels_get(ctx->net, (len * BITS_PER_BYTE) - 1); 546 if (err) 547 return err; 548 break; 549 #endif 550 #ifdef CONFIG_NF_CONNTRACK_ZONES 551 case NFT_CT_ZONE: 552 if (!nft_ct_tmpl_alloc_pcpu()) 553 return -ENOMEM; 554 nft_ct_pcpu_template_refcnt++; 555 len = sizeof(u16); 556 break; 557 #endif 558 #ifdef CONFIG_NF_CONNTRACK_EVENTS 559 case NFT_CT_EVENTMASK: 560 if (tb[NFTA_CT_DIRECTION]) 561 return -EINVAL; 562 len = sizeof(u32); 563 break; 564 #endif 565 default: 566 return -EOPNOTSUPP; 567 } 568 569 if (tb[NFTA_CT_DIRECTION]) { 570 priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]); 571 switch (priv->dir) { 572 case IP_CT_DIR_ORIGINAL: 573 case IP_CT_DIR_REPLY: 574 break; 575 default: 576 err = -EINVAL; 577 goto err1; 578 } 579 } 580 581 priv->sreg = nft_parse_register(tb[NFTA_CT_SREG]); 582 err = nft_validate_register_load(priv->sreg, len); 583 if (err < 0) 584 goto err1; 585 586 err = nft_ct_netns_get(ctx->net, ctx->afi->family); 587 if (err < 0) 588 goto err1; 589 590 return 0; 591 592 err1: 593 __nft_ct_set_destroy(ctx, priv); 594 return err; 595 } 596 597 static void nft_ct_get_destroy(const struct nft_ctx *ctx, 598 const struct nft_expr *expr) 599 { 600 nf_ct_netns_put(ctx->net, ctx->afi->family); 601 } 602 603 static void nft_ct_set_destroy(const struct nft_ctx *ctx, 604 const struct nft_expr *expr) 605 { 606 struct nft_ct *priv = nft_expr_priv(expr); 607 608 __nft_ct_set_destroy(ctx, priv); 609 nft_ct_netns_put(ctx->net, ctx->afi->family); 610 } 611 612 static int nft_ct_get_dump(struct sk_buff *skb, const struct nft_expr *expr) 613 { 614 const struct nft_ct *priv = nft_expr_priv(expr); 615 616 if (nft_dump_register(skb, NFTA_CT_DREG, priv->dreg)) 617 goto nla_put_failure; 618 if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key))) 619 goto nla_put_failure; 620 621 switch (priv->key) { 622 case NFT_CT_SRC: 623 case NFT_CT_DST: 624 case NFT_CT_PROTO_SRC: 625 case NFT_CT_PROTO_DST: 626 if (nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir)) 627 goto nla_put_failure; 628 break; 629 case NFT_CT_BYTES: 630 case NFT_CT_PKTS: 631 case NFT_CT_AVGPKT: 632 case NFT_CT_ZONE: 633 if (priv->dir < IP_CT_DIR_MAX && 634 nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir)) 635 goto nla_put_failure; 636 break; 637 default: 638 break; 639 } 640 641 return 0; 642 643 nla_put_failure: 644 return -1; 645 } 646 647 static int nft_ct_set_dump(struct sk_buff *skb, const struct nft_expr *expr) 648 { 649 const struct nft_ct *priv = nft_expr_priv(expr); 650 651 if (nft_dump_register(skb, NFTA_CT_SREG, priv->sreg)) 652 goto nla_put_failure; 653 if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key))) 654 goto nla_put_failure; 655 656 switch (priv->key) { 657 case NFT_CT_ZONE: 658 if (priv->dir < IP_CT_DIR_MAX && 659 nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir)) 660 goto nla_put_failure; 661 break; 662 default: 663 break; 664 } 665 666 return 0; 667 668 nla_put_failure: 669 return -1; 670 } 671 672 static struct nft_expr_type nft_ct_type; 673 static const struct nft_expr_ops nft_ct_get_ops = { 674 .type = &nft_ct_type, 675 .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)), 676 .eval = nft_ct_get_eval, 677 .init = nft_ct_get_init, 678 .destroy = nft_ct_get_destroy, 679 .dump = nft_ct_get_dump, 680 }; 681 682 static const struct nft_expr_ops nft_ct_set_ops = { 683 .type = &nft_ct_type, 684 .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)), 685 .eval = nft_ct_set_eval, 686 .init = nft_ct_set_init, 687 .destroy = nft_ct_set_destroy, 688 .dump = nft_ct_set_dump, 689 }; 690 691 #ifdef CONFIG_NF_CONNTRACK_ZONES 692 static const struct nft_expr_ops nft_ct_set_zone_ops = { 693 .type = &nft_ct_type, 694 .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)), 695 .eval = nft_ct_set_zone_eval, 696 .init = nft_ct_set_init, 697 .destroy = nft_ct_set_destroy, 698 .dump = nft_ct_set_dump, 699 }; 700 #endif 701 702 static const struct nft_expr_ops * 703 nft_ct_select_ops(const struct nft_ctx *ctx, 704 const struct nlattr * const tb[]) 705 { 706 if (tb[NFTA_CT_KEY] == NULL) 707 return ERR_PTR(-EINVAL); 708 709 if (tb[NFTA_CT_DREG] && tb[NFTA_CT_SREG]) 710 return ERR_PTR(-EINVAL); 711 712 if (tb[NFTA_CT_DREG]) 713 return &nft_ct_get_ops; 714 715 if (tb[NFTA_CT_SREG]) { 716 #ifdef CONFIG_NF_CONNTRACK_ZONES 717 if (nla_get_be32(tb[NFTA_CT_KEY]) == htonl(NFT_CT_ZONE)) 718 return &nft_ct_set_zone_ops; 719 #endif 720 return &nft_ct_set_ops; 721 } 722 723 return ERR_PTR(-EINVAL); 724 } 725 726 static struct nft_expr_type nft_ct_type __read_mostly = { 727 .name = "ct", 728 .select_ops = nft_ct_select_ops, 729 .policy = nft_ct_policy, 730 .maxattr = NFTA_CT_MAX, 731 .owner = THIS_MODULE, 732 }; 733 734 static void nft_notrack_eval(const struct nft_expr *expr, 735 struct nft_regs *regs, 736 const struct nft_pktinfo *pkt) 737 { 738 struct sk_buff *skb = pkt->skb; 739 enum ip_conntrack_info ctinfo; 740 struct nf_conn *ct; 741 742 ct = nf_ct_get(pkt->skb, &ctinfo); 743 /* Previously seen (loopback or untracked)? Ignore. */ 744 if (ct || ctinfo == IP_CT_UNTRACKED) 745 return; 746 747 nf_ct_set(skb, ct, IP_CT_UNTRACKED); 748 } 749 750 static struct nft_expr_type nft_notrack_type; 751 static const struct nft_expr_ops nft_notrack_ops = { 752 .type = &nft_notrack_type, 753 .size = NFT_EXPR_SIZE(0), 754 .eval = nft_notrack_eval, 755 }; 756 757 static struct nft_expr_type nft_notrack_type __read_mostly = { 758 .name = "notrack", 759 .ops = &nft_notrack_ops, 760 .owner = THIS_MODULE, 761 }; 762 763 static int nft_ct_helper_obj_init(const struct nft_ctx *ctx, 764 const struct nlattr * const tb[], 765 struct nft_object *obj) 766 { 767 struct nft_ct_helper_obj *priv = nft_obj_data(obj); 768 struct nf_conntrack_helper *help4, *help6; 769 char name[NF_CT_HELPER_NAME_LEN]; 770 int family = ctx->afi->family; 771 772 if (!tb[NFTA_CT_HELPER_NAME] || !tb[NFTA_CT_HELPER_L4PROTO]) 773 return -EINVAL; 774 775 priv->l4proto = nla_get_u8(tb[NFTA_CT_HELPER_L4PROTO]); 776 if (!priv->l4proto) 777 return -ENOENT; 778 779 nla_strlcpy(name, tb[NFTA_CT_HELPER_NAME], sizeof(name)); 780 781 if (tb[NFTA_CT_HELPER_L3PROTO]) 782 family = ntohs(nla_get_be16(tb[NFTA_CT_HELPER_L3PROTO])); 783 784 help4 = NULL; 785 help6 = NULL; 786 787 switch (family) { 788 case NFPROTO_IPV4: 789 if (ctx->afi->family == NFPROTO_IPV6) 790 return -EINVAL; 791 792 help4 = nf_conntrack_helper_try_module_get(name, family, 793 priv->l4proto); 794 break; 795 case NFPROTO_IPV6: 796 if (ctx->afi->family == NFPROTO_IPV4) 797 return -EINVAL; 798 799 help6 = nf_conntrack_helper_try_module_get(name, family, 800 priv->l4proto); 801 break; 802 case NFPROTO_NETDEV: /* fallthrough */ 803 case NFPROTO_BRIDGE: /* same */ 804 case NFPROTO_INET: 805 help4 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV4, 806 priv->l4proto); 807 help6 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV6, 808 priv->l4proto); 809 break; 810 default: 811 return -EAFNOSUPPORT; 812 } 813 814 /* && is intentional; only error if INET found neither ipv4 or ipv6 */ 815 if (!help4 && !help6) 816 return -ENOENT; 817 818 priv->helper4 = help4; 819 priv->helper6 = help6; 820 821 return 0; 822 } 823 824 static void nft_ct_helper_obj_destroy(struct nft_object *obj) 825 { 826 struct nft_ct_helper_obj *priv = nft_obj_data(obj); 827 828 if (priv->helper4) 829 nf_conntrack_helper_put(priv->helper4); 830 if (priv->helper6) 831 nf_conntrack_helper_put(priv->helper6); 832 } 833 834 static void nft_ct_helper_obj_eval(struct nft_object *obj, 835 struct nft_regs *regs, 836 const struct nft_pktinfo *pkt) 837 { 838 const struct nft_ct_helper_obj *priv = nft_obj_data(obj); 839 struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb); 840 struct nf_conntrack_helper *to_assign = NULL; 841 struct nf_conn_help *help; 842 843 if (!ct || 844 nf_ct_is_confirmed(ct) || 845 nf_ct_is_template(ct) || 846 priv->l4proto != nf_ct_protonum(ct)) 847 return; 848 849 switch (nf_ct_l3num(ct)) { 850 case NFPROTO_IPV4: 851 to_assign = priv->helper4; 852 break; 853 case NFPROTO_IPV6: 854 to_assign = priv->helper6; 855 break; 856 default: 857 WARN_ON_ONCE(1); 858 return; 859 } 860 861 if (!to_assign) 862 return; 863 864 if (test_bit(IPS_HELPER_BIT, &ct->status)) 865 return; 866 867 help = nf_ct_helper_ext_add(ct, to_assign, GFP_ATOMIC); 868 if (help) { 869 rcu_assign_pointer(help->helper, to_assign); 870 set_bit(IPS_HELPER_BIT, &ct->status); 871 } 872 } 873 874 static int nft_ct_helper_obj_dump(struct sk_buff *skb, 875 struct nft_object *obj, bool reset) 876 { 877 const struct nft_ct_helper_obj *priv = nft_obj_data(obj); 878 const struct nf_conntrack_helper *helper = priv->helper4; 879 u16 family; 880 881 if (nla_put_string(skb, NFTA_CT_HELPER_NAME, helper->name)) 882 return -1; 883 884 if (nla_put_u8(skb, NFTA_CT_HELPER_L4PROTO, priv->l4proto)) 885 return -1; 886 887 if (priv->helper4 && priv->helper6) 888 family = NFPROTO_INET; 889 else if (priv->helper6) 890 family = NFPROTO_IPV6; 891 else 892 family = NFPROTO_IPV4; 893 894 if (nla_put_be16(skb, NFTA_CT_HELPER_L3PROTO, htons(family))) 895 return -1; 896 897 return 0; 898 } 899 900 static const struct nla_policy nft_ct_helper_policy[NFTA_CT_HELPER_MAX + 1] = { 901 [NFTA_CT_HELPER_NAME] = { .type = NLA_STRING, 902 .len = NF_CT_HELPER_NAME_LEN - 1 }, 903 [NFTA_CT_HELPER_L3PROTO] = { .type = NLA_U16 }, 904 [NFTA_CT_HELPER_L4PROTO] = { .type = NLA_U8 }, 905 }; 906 907 static struct nft_object_type nft_ct_helper_obj_type; 908 static const struct nft_object_ops nft_ct_helper_obj_ops = { 909 .type = &nft_ct_helper_obj_type, 910 .size = sizeof(struct nft_ct_helper_obj), 911 .eval = nft_ct_helper_obj_eval, 912 .init = nft_ct_helper_obj_init, 913 .destroy = nft_ct_helper_obj_destroy, 914 .dump = nft_ct_helper_obj_dump, 915 }; 916 917 static struct nft_object_type nft_ct_helper_obj_type __read_mostly = { 918 .type = NFT_OBJECT_CT_HELPER, 919 .ops = &nft_ct_helper_obj_ops, 920 .maxattr = NFTA_CT_HELPER_MAX, 921 .policy = nft_ct_helper_policy, 922 .owner = THIS_MODULE, 923 }; 924 925 static int __init nft_ct_module_init(void) 926 { 927 int err; 928 929 BUILD_BUG_ON(NF_CT_LABELS_MAX_SIZE > NFT_REG_SIZE); 930 931 err = nft_register_expr(&nft_ct_type); 932 if (err < 0) 933 return err; 934 935 err = nft_register_expr(&nft_notrack_type); 936 if (err < 0) 937 goto err1; 938 939 err = nft_register_obj(&nft_ct_helper_obj_type); 940 if (err < 0) 941 goto err2; 942 943 return 0; 944 945 err2: 946 nft_unregister_expr(&nft_notrack_type); 947 err1: 948 nft_unregister_expr(&nft_ct_type); 949 return err; 950 } 951 952 static void __exit nft_ct_module_exit(void) 953 { 954 nft_unregister_obj(&nft_ct_helper_obj_type); 955 nft_unregister_expr(&nft_notrack_type); 956 nft_unregister_expr(&nft_ct_type); 957 } 958 959 module_init(nft_ct_module_init); 960 module_exit(nft_ct_module_exit); 961 962 MODULE_LICENSE("GPL"); 963 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); 964 MODULE_ALIAS_NFT_EXPR("ct"); 965 MODULE_ALIAS_NFT_EXPR("notrack"); 966 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_HELPER); 967