net/netfilter/nft_meta.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
   4  * Copyright (c) 2014 Intel Corporation
   5  * Author: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
   6  *
   7  * Development of this code funded by Astaro AG (http://www.astaro.com/)
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/netlink.h>
  12 #include <linux/netfilter.h>
  13 #include <linux/netfilter/nf_tables.h>
  14 #include <linux/in.h>
  15 #include <linux/ip.h>
  16 #include <linux/ipv6.h>
  17 #include <linux/random.h>
  18 #include <linux/smp.h>
  19 #include <linux/static_key.h>
  20 #include <net/dst.h>
  21 #include <net/ip.h>
  22 #include <net/sock.h>
  23 #include <net/tcp_states.h> /* for TCP_TIME_WAIT */
  24 #include <net/netfilter/nf_tables.h>
  25 #include <net/netfilter/nf_tables_core.h>
  26 #include <net/netfilter/nft_meta.h>
  27 #include <net/netfilter/nf_tables_offload.h>
  28
  29 #include <uapi/linux/netfilter_bridge.h> /* NF_BR_PRE_ROUTING */
  30
  31 #define NFT_META_SECS_PER_MINUTE        60
  32 #define NFT_META_SECS_PER_HOUR          3600
  33 #define NFT_META_SECS_PER_DAY           86400
  34 #define NFT_META_DAYS_PER_WEEK          7
  35
  36 static u8 nft_meta_weekday(void)
  37 {
  38         time64_t secs = ktime_get_real_seconds();
  39         unsigned int dse;
  40         u8 wday;
  41
  42         secs -= NFT_META_SECS_PER_MINUTE * sys_tz.tz_minuteswest;
  43         dse = div_u64(secs, NFT_META_SECS_PER_DAY);
  44         wday = (4 + dse) % NFT_META_DAYS_PER_WEEK;
  45
  46         return wday;
  47 }
  48
  49 static u32 nft_meta_hour(time64_t secs)
  50 {
  51         struct tm tm;
  52
  53         time64_to_tm(secs, 0, &tm);
  54
  55         return tm.tm_hour * NFT_META_SECS_PER_HOUR
  56                 + tm.tm_min * NFT_META_SECS_PER_MINUTE
  57                 + tm.tm_sec;
  58 }
  59
  60 static noinline_for_stack void
  61 nft_meta_get_eval_time(enum nft_meta_keys key,
  62                        u32 *dest)
  63 {
  64         switch (key) {
  65         case NFT_META_TIME_NS:
  66                 nft_reg_store64((u64 *)dest, ktime_get_real_ns());
  67                 break;
  68         case NFT_META_TIME_DAY:
  69                 nft_reg_store8(dest, nft_meta_weekday());
  70                 break;
  71         case NFT_META_TIME_HOUR:
  72                 *dest = nft_meta_hour(ktime_get_real_seconds());
  73                 break;
  74         default:
  75                 break;
  76         }
  77 }
  78
  79 static noinline bool
  80 nft_meta_get_eval_pkttype_lo(const struct nft_pktinfo *pkt,
  81                              u32 *dest)
  82 {
  83         const struct sk_buff *skb = pkt->skb;
  84
  85         switch (nft_pf(pkt)) {
  86         case NFPROTO_IPV4:
  87                 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
  88                         nft_reg_store8(dest, PACKET_MULTICAST);
  89                 else
  90                         nft_reg_store8(dest, PACKET_BROADCAST);
  91                 break;
  92         case NFPROTO_IPV6:
  93                 nft_reg_store8(dest, PACKET_MULTICAST);
  94                 break;
  95         case NFPROTO_NETDEV:
  96                 switch (skb->protocol) {
  97                 case htons(ETH_P_IP): {
  98                         int noff = skb_network_offset(skb);
  99                         struct iphdr *iph, _iph;
 100
 101                         iph = skb_header_pointer(skb, noff,
 102                                                  sizeof(_iph), &_iph);
 103                         if (!iph)
 104                                 return false;
 105
 106                         if (ipv4_is_multicast(iph->daddr))
 107                                 nft_reg_store8(dest, PACKET_MULTICAST);
 108                         else
 109                                 nft_reg_store8(dest, PACKET_BROADCAST);
 110
 111                         break;
 112                 }
 113                 case htons(ETH_P_IPV6):
 114                         nft_reg_store8(dest, PACKET_MULTICAST);
 115                         break;
 116                 default:
 117                         WARN_ON_ONCE(1);
 118                         return false;
 119                 }
 120                 break;
 121         default:
 122                 WARN_ON_ONCE(1);
 123                 return false;
 124         }
 125
 126         return true;
 127 }
 128
 129 static noinline bool
 130 nft_meta_get_eval_skugid(enum nft_meta_keys key,
 131                          u32 *dest,
 132                          const struct nft_pktinfo *pkt)
 133 {
 134         struct sock *sk = skb_to_full_sk(pkt->skb);
 135         struct socket *sock;
 136
 137         if (!sk || !sk_fullsock(sk) || !net_eq(nft_net(pkt), sock_net(sk)))
 138                 return false;
 139
 140         read_lock_bh(&sk->sk_callback_lock);
 141         sock = sk->sk_socket;
 142         if (!sock || !sock->file) {
 143                 read_unlock_bh(&sk->sk_callback_lock);
 144                 return false;
 145         }
 146
 147         switch (key) {
 148         case NFT_META_SKUID:
 149                 *dest = from_kuid_munged(sock_net(sk)->user_ns,
 150                                          sock->file->f_cred->fsuid);
 151                 break;
 152         case NFT_META_SKGID:
 153                 *dest = from_kgid_munged(sock_net(sk)->user_ns,
 154                                          sock->file->f_cred->fsgid);
 155                 break;
 156         default:
 157                 break;
 158         }
 159
 160         read_unlock_bh(&sk->sk_callback_lock);
 161         return true;
 162 }
 163
 164 #ifdef CONFIG_CGROUP_NET_CLASSID
 165 static noinline bool
 166 nft_meta_get_eval_cgroup(u32 *dest, const struct nft_pktinfo *pkt)
 167 {
 168         struct sock *sk = skb_to_full_sk(pkt->skb);
 169
 170         if (!sk || !sk_fullsock(sk) || !net_eq(nft_net(pkt), sock_net(sk)))
 171                 return false;
 172
 173         *dest = sock_cgroup_classid(&sk->sk_cgrp_data);
 174         return true;
 175 }
 176 #endif
 177
 178 static noinline bool nft_meta_get_eval_kind(enum nft_meta_keys key,
 179                                             u32 *dest,
 180                                             const struct nft_pktinfo *pkt)
 181 {
 182         const struct net_device *in = nft_in(pkt), *out = nft_out(pkt);
 183
 184         switch (key) {
 185         case NFT_META_IIFKIND:
 186                 if (!in || !in->rtnl_link_ops)
 187                         return false;
 188                 strscpy_pad((char *)dest, in->rtnl_link_ops->kind, IFNAMSIZ);
 189                 break;
 190         case NFT_META_OIFKIND:
 191                 if (!out || !out->rtnl_link_ops)
 192                         return false;
 193                 strscpy_pad((char *)dest, out->rtnl_link_ops->kind, IFNAMSIZ);
 194                 break;
 195         default:
 196                 return false;
 197         }
 198
 199         return true;
 200 }
 201
 202 static void nft_meta_store_ifindex(u32 *dest, const struct net_device *dev)
 203 {
 204         *dest = dev ? dev->ifindex : 0;
 205 }
 206
 207 static void nft_meta_store_ifname(u32 *dest, const struct net_device *dev)
 208 {
 209         strscpy_pad((char *)dest, dev ? dev->name : "", IFNAMSIZ);
 210 }
 211
 212 static bool nft_meta_store_iftype(u32 *dest, const struct net_device *dev)
 213 {
 214         if (!dev)
 215                 return false;
 216
 217         nft_reg_store16(dest, dev->type);
 218         return true;
 219 }
 220
 221 static bool nft_meta_store_ifgroup(u32 *dest, const struct net_device *dev)
 222 {
 223         if (!dev)
 224                 return false;
 225
 226         *dest = dev->group;
 227         return true;
 228 }
 229
 230 static bool nft_meta_get_eval_ifname(enum nft_meta_keys key, u32 *dest,
 231                                      const struct nft_pktinfo *pkt)
 232 {
 233         switch (key) {
 234         case NFT_META_IIFNAME:
 235                 nft_meta_store_ifname(dest, nft_in(pkt));
 236                 break;
 237         case NFT_META_OIFNAME:
 238                 nft_meta_store_ifname(dest, nft_out(pkt));
 239                 break;
 240         case NFT_META_IIF:
 241                 nft_meta_store_ifindex(dest, nft_in(pkt));
 242                 break;
 243         case NFT_META_OIF:
 244                 nft_meta_store_ifindex(dest, nft_out(pkt));
 245                 break;
 246         case NFT_META_IFTYPE:
 247                 if (!nft_meta_store_iftype(dest, pkt->skb->dev))
 248                         return false;
 249                 break;
 250         case __NFT_META_IIFTYPE:
 251                 if (!nft_meta_store_iftype(dest, nft_in(pkt)))
 252                         return false;
 253                 break;
 254         case NFT_META_OIFTYPE:
 255                 if (!nft_meta_store_iftype(dest, nft_out(pkt)))
 256                         return false;
 257                 break;
 258         case NFT_META_IIFGROUP:
 259                 if (!nft_meta_store_ifgroup(dest, nft_in(pkt)))
 260                         return false;
 261                 break;
 262         case NFT_META_OIFGROUP:
 263                 if (!nft_meta_store_ifgroup(dest, nft_out(pkt)))
 264                         return false;
 265                 break;
 266         default:
 267                 return false;
 268         }
 269
 270         return true;
 271 }
 272
 273 #ifdef CONFIG_IP_ROUTE_CLASSID
 274 static noinline bool
 275 nft_meta_get_eval_rtclassid(const struct sk_buff *skb, u32 *dest)
 276 {
 277         const struct dst_entry *dst = skb_dst(skb);
 278
 279         if (!dst)
 280                 return false;
 281
 282         *dest = dst->tclassid;
 283         return true;
 284 }
 285 #endif
 286
 287 static noinline u32 nft_meta_get_eval_sdif(const struct nft_pktinfo *pkt)
 288 {
 289         switch (nft_pf(pkt)) {
 290         case NFPROTO_IPV4:
 291                 return inet_sdif(pkt->skb);
 292         case NFPROTO_IPV6:
 293                 return inet6_sdif(pkt->skb);
 294         }
 295
 296         return 0;
 297 }
 298
 299 static noinline void
 300 nft_meta_get_eval_sdifname(u32 *dest, const struct nft_pktinfo *pkt)
 301 {
 302         u32 sdif = nft_meta_get_eval_sdif(pkt);
 303         const struct net_device *dev;
 304
 305         dev = sdif ? dev_get_by_index_rcu(nft_net(pkt), sdif) : NULL;
 306         nft_meta_store_ifname(dest, dev);
 307 }
 308
 309 void nft_meta_get_eval(const struct nft_expr *expr,
 310                        struct nft_regs *regs,
 311                        const struct nft_pktinfo *pkt)
 312 {
 313         const struct nft_meta *priv = nft_expr_priv(expr);
 314         const struct sk_buff *skb = pkt->skb;
 315         u32 *dest = &regs->data[priv->dreg];
 316
 317         switch (priv->key) {
 318         case NFT_META_LEN:
 319                 *dest = skb->len;
 320                 break;
 321         case NFT_META_PROTOCOL:
 322                 nft_reg_store16(dest, (__force u16)skb->protocol);
 323                 break;
 324         case NFT_META_NFPROTO:
 325                 nft_reg_store8(dest, nft_pf(pkt));
 326                 break;
 327         case NFT_META_L4PROTO:
 328                 if (!(pkt->flags & NFT_PKTINFO_L4PROTO))
 329                         goto err;
 330                 nft_reg_store8(dest, pkt->tprot);
 331                 break;
 332         case NFT_META_PRIORITY:
 333                 *dest = skb->priority;
 334                 break;
 335         case NFT_META_MARK:
 336                 *dest = skb->mark;
 337                 break;
 338         case NFT_META_IIF:
 339         case NFT_META_OIF:
 340         case NFT_META_IIFNAME:
 341         case NFT_META_OIFNAME:
 342         case NFT_META_IIFTYPE:
 343         case NFT_META_OIFTYPE:
 344         case NFT_META_IIFGROUP:
 345         case NFT_META_OIFGROUP:
 346                 if (!nft_meta_get_eval_ifname(priv->key, dest, pkt))
 347                         goto err;
 348                 break;
 349         case NFT_META_SKUID:
 350         case NFT_META_SKGID:
 351                 if (!nft_meta_get_eval_skugid(priv->key, dest, pkt))
 352                         goto err;
 353                 break;
 354 #ifdef CONFIG_IP_ROUTE_CLASSID
 355         case NFT_META_RTCLASSID:
 356                 if (!nft_meta_get_eval_rtclassid(skb, dest))
 357                         goto err;
 358                 break;
 359 #endif
 360 #ifdef CONFIG_NETWORK_SECMARK
 361         case NFT_META_SECMARK:
 362                 *dest = skb->secmark;
 363                 break;
 364 #endif
 365         case NFT_META_PKTTYPE:
 366                 if (skb->pkt_type != PACKET_LOOPBACK) {
 367                         nft_reg_store8(dest, skb->pkt_type);
 368                         break;
 369                 }
 370
 371                 if (!nft_meta_get_eval_pkttype_lo(pkt, dest))
 372                         goto err;
 373                 break;
 374         case NFT_META_CPU:
 375                 *dest = raw_smp_processor_id();
 376                 break;
 377 #ifdef CONFIG_CGROUP_NET_CLASSID
 378         case NFT_META_CGROUP:
 379                 if (!nft_meta_get_eval_cgroup(dest, pkt))
 380                         goto err;
 381                 break;
 382 #endif
 383         case NFT_META_PRANDOM:
 384                 *dest = get_random_u32();
 385                 break;
 386 #ifdef CONFIG_XFRM
 387         case NFT_META_SECPATH:
 388                 nft_reg_store8(dest, secpath_exists(skb));
 389                 break;
 390 #endif
 391         case NFT_META_IIFKIND:
 392         case NFT_META_OIFKIND:
 393                 if (!nft_meta_get_eval_kind(priv->key, dest, pkt))
 394                         goto err;
 395                 break;
 396         case NFT_META_TIME_NS:
 397         case NFT_META_TIME_DAY:
 398         case NFT_META_TIME_HOUR:
 399                 nft_meta_get_eval_time(priv->key, dest);
 400                 break;
 401         case NFT_META_SDIF:
 402                 *dest = nft_meta_get_eval_sdif(pkt);
 403                 break;
 404         case NFT_META_SDIFNAME:
 405                 nft_meta_get_eval_sdifname(dest, pkt);
 406                 break;
 407         default:
 408                 WARN_ON(1);
 409                 goto err;
 410         }
 411         return;
 412
 413 err:
 414         regs->verdict.code = NFT_BREAK;
 415 }
 416 EXPORT_SYMBOL_GPL(nft_meta_get_eval);
 417
 418 void nft_meta_set_eval(const struct nft_expr *expr,
 419                        struct nft_regs *regs,
 420                        const struct nft_pktinfo *pkt)
 421 {
 422         const struct nft_meta *meta = nft_expr_priv(expr);
 423         struct sk_buff *skb = pkt->skb;
 424         u32 *sreg = &regs->data[meta->sreg];
 425         u32 value = *sreg;
 426         u8 value8;
 427
 428         switch (meta->key) {
 429         case NFT_META_MARK:
 430                 skb->mark = value;
 431                 break;
 432         case NFT_META_PRIORITY:
 433                 skb->priority = value;
 434                 break;
 435         case NFT_META_PKTTYPE:
 436                 value8 = nft_reg_load8(sreg);
 437
 438                 if (skb->pkt_type != value8 &&
 439                     skb_pkt_type_ok(value8) &&
 440                     skb_pkt_type_ok(skb->pkt_type))
 441                         skb->pkt_type = value8;
 442                 break;
 443         case NFT_META_NFTRACE:
 444                 value8 = nft_reg_load8(sreg);
 445
 446                 skb->nf_trace = !!value8;
 447                 break;
 448 #ifdef CONFIG_NETWORK_SECMARK
 449         case NFT_META_SECMARK:
 450                 skb->secmark = value;
 451                 break;
 452 #endif
 453         default:
 454                 WARN_ON(1);
 455         }
 456 }
 457 EXPORT_SYMBOL_GPL(nft_meta_set_eval);
 458
 459 const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
 460         [NFTA_META_DREG]        = { .type = NLA_U32 },
 461         [NFTA_META_KEY]         = NLA_POLICY_MAX(NLA_BE32, 255),
 462         [NFTA_META_SREG]        = { .type = NLA_U32 },
 463 };
 464 EXPORT_SYMBOL_GPL(nft_meta_policy);
 465
 466 int nft_meta_get_init(const struct nft_ctx *ctx,
 467                       const struct nft_expr *expr,
 468                       const struct nlattr * const tb[])
 469 {
 470         struct nft_meta *priv = nft_expr_priv(expr);
 471         unsigned int len;
 472
 473         priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
 474         switch (priv->key) {
 475         case NFT_META_PROTOCOL:
 476         case NFT_META_IIFTYPE:
 477         case NFT_META_OIFTYPE:
 478                 len = sizeof(u16);
 479                 break;
 480         case NFT_META_NFPROTO:
 481         case NFT_META_L4PROTO:
 482         case NFT_META_LEN:
 483         case NFT_META_PRIORITY:
 484         case NFT_META_MARK:
 485         case NFT_META_IIF:
 486         case NFT_META_OIF:
 487         case NFT_META_SDIF:
 488         case NFT_META_SKUID:
 489         case NFT_META_SKGID:
 490 #ifdef CONFIG_IP_ROUTE_CLASSID
 491         case NFT_META_RTCLASSID:
 492 #endif
 493 #ifdef CONFIG_NETWORK_SECMARK
 494         case NFT_META_SECMARK:
 495 #endif
 496         case NFT_META_PKTTYPE:
 497         case NFT_META_CPU:
 498         case NFT_META_IIFGROUP:
 499         case NFT_META_OIFGROUP:
 500 #ifdef CONFIG_CGROUP_NET_CLASSID
 501         case NFT_META_CGROUP:
 502 #endif
 503                 len = sizeof(u32);
 504                 break;
 505         case NFT_META_IIFNAME:
 506         case NFT_META_OIFNAME:
 507         case NFT_META_IIFKIND:
 508         case NFT_META_OIFKIND:
 509         case NFT_META_SDIFNAME:
 510                 len = IFNAMSIZ;
 511                 break;
 512         case NFT_META_PRANDOM:
 513                 len = sizeof(u32);
 514                 break;
 515 #ifdef CONFIG_XFRM
 516         case NFT_META_SECPATH:
 517                 len = sizeof(u8);
 518                 break;
 519 #endif
 520         case NFT_META_TIME_NS:
 521                 len = sizeof(u64);
 522                 break;
 523         case NFT_META_TIME_DAY:
 524                 len = sizeof(u8);
 525                 break;
 526         case NFT_META_TIME_HOUR:
 527                 len = sizeof(u32);
 528                 break;
 529         default:
 530                 return -EOPNOTSUPP;
 531         }
 532
 533         priv->len = len;
 534         return nft_parse_register_store(ctx, tb[NFTA_META_DREG], &priv->dreg,
 535                                         NULL, NFT_DATA_VALUE, len);
 536 }
 537 EXPORT_SYMBOL_GPL(nft_meta_get_init);
 538
 539 static int nft_meta_get_validate_sdif(const struct nft_ctx *ctx)
 540 {
 541         unsigned int hooks;
 542
 543         switch (ctx->family) {
 544         case NFPROTO_IPV4:
 545         case NFPROTO_IPV6:
 546         case NFPROTO_INET:
 547                 hooks = (1 << NF_INET_LOCAL_IN) |
 548                         (1 << NF_INET_FORWARD);
 549                 break;
 550         default:
 551                 return -EOPNOTSUPP;
 552         }
 553
 554         return nft_chain_validate_hooks(ctx->chain, hooks);
 555 }
 556
 557 static int nft_meta_get_validate_xfrm(const struct nft_ctx *ctx)
 558 {
 559 #ifdef CONFIG_XFRM
 560         unsigned int hooks;
 561
 562         switch (ctx->family) {
 563         case NFPROTO_NETDEV:
 564                 hooks = 1 << NF_NETDEV_INGRESS;
 565                 break;
 566         case NFPROTO_IPV4:
 567         case NFPROTO_IPV6:
 568         case NFPROTO_INET:
 569                 hooks = (1 << NF_INET_PRE_ROUTING) |
 570                         (1 << NF_INET_LOCAL_IN) |
 571                         (1 << NF_INET_FORWARD);
 572                 break;
 573         default:
 574                 return -EOPNOTSUPP;
 575         }
 576
 577         return nft_chain_validate_hooks(ctx->chain, hooks);
 578 #else
 579         return 0;
 580 #endif
 581 }
 582
 583 static int nft_meta_get_validate(const struct nft_ctx *ctx,
 584                                  const struct nft_expr *expr)
 585 {
 586         const struct nft_meta *priv = nft_expr_priv(expr);
 587
 588         switch (priv->key) {
 589         case NFT_META_SECPATH:
 590                 return nft_meta_get_validate_xfrm(ctx);
 591         case NFT_META_SDIF:
 592         case NFT_META_SDIFNAME:
 593                 return nft_meta_get_validate_sdif(ctx);
 594         default:
 595                 break;
 596         }
 597
 598         return 0;
 599 }
 600
 601 int nft_meta_set_validate(const struct nft_ctx *ctx,
 602                           const struct nft_expr *expr)
 603 {
 604         struct nft_meta *priv = nft_expr_priv(expr);
 605         unsigned int hooks;
 606
 607         if (priv->key != NFT_META_PKTTYPE)
 608                 return 0;
 609
 610         switch (ctx->family) {
 611         case NFPROTO_BRIDGE:
 612                 hooks = 1 << NF_BR_PRE_ROUTING;
 613                 break;
 614         case NFPROTO_NETDEV:
 615                 hooks = 1 << NF_NETDEV_INGRESS;
 616                 break;
 617         case NFPROTO_IPV4:
 618         case NFPROTO_IPV6:
 619         case NFPROTO_INET:
 620                 hooks = 1 << NF_INET_PRE_ROUTING;
 621                 break;
 622         default:
 623                 return -EOPNOTSUPP;
 624         }
 625
 626         return nft_chain_validate_hooks(ctx->chain, hooks);
 627 }
 628 EXPORT_SYMBOL_GPL(nft_meta_set_validate);
 629
 630 int nft_meta_set_init(const struct nft_ctx *ctx,
 631                       const struct nft_expr *expr,
 632                       const struct nlattr * const tb[])
 633 {
 634         struct nft_meta *priv = nft_expr_priv(expr);
 635         unsigned int len;
 636         int err;
 637
 638         priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
 639         switch (priv->key) {
 640         case NFT_META_MARK:
 641         case NFT_META_PRIORITY:
 642 #ifdef CONFIG_NETWORK_SECMARK
 643         case NFT_META_SECMARK:
 644 #endif
 645                 len = sizeof(u32);
 646                 break;
 647         case NFT_META_NFTRACE:
 648                 len = sizeof(u8);
 649                 break;
 650         case NFT_META_PKTTYPE:
 651                 len = sizeof(u8);
 652                 break;
 653         default:
 654                 return -EOPNOTSUPP;
 655         }
 656
 657         priv->len = len;
 658         err = nft_parse_register_load(ctx, tb[NFTA_META_SREG], &priv->sreg, len);
 659         if (err < 0)
 660                 return err;
 661
 662         if (priv->key == NFT_META_NFTRACE)
 663                 static_branch_inc(&nft_trace_enabled);
 664
 665         return 0;
 666 }
 667 EXPORT_SYMBOL_GPL(nft_meta_set_init);
 668
 669 int nft_meta_get_dump(struct sk_buff *skb,
 670                       const struct nft_expr *expr, bool reset)
 671 {
 672         const struct nft_meta *priv = nft_expr_priv(expr);
 673
 674         if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
 675                 goto nla_put_failure;
 676         if (nft_dump_register(skb, NFTA_META_DREG, priv->dreg))
 677                 goto nla_put_failure;
 678         return 0;
 679
 680 nla_put_failure:
 681         return -1;
 682 }
 683 EXPORT_SYMBOL_GPL(nft_meta_get_dump);
 684
 685 int nft_meta_set_dump(struct sk_buff *skb,
 686                       const struct nft_expr *expr, bool reset)
 687 {
 688         const struct nft_meta *priv = nft_expr_priv(expr);
 689
 690         if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
 691                 goto nla_put_failure;
 692         if (nft_dump_register(skb, NFTA_META_SREG, priv->sreg))
 693                 goto nla_put_failure;
 694
 695         return 0;
 696
 697 nla_put_failure:
 698         return -1;
 699 }
 700 EXPORT_SYMBOL_GPL(nft_meta_set_dump);
 701
 702 void nft_meta_set_destroy(const struct nft_ctx *ctx,
 703                           const struct nft_expr *expr)
 704 {
 705         const struct nft_meta *priv = nft_expr_priv(expr);
 706
 707         if (priv->key == NFT_META_NFTRACE)
 708                 static_branch_dec(&nft_trace_enabled);
 709 }
 710 EXPORT_SYMBOL_GPL(nft_meta_set_destroy);
 711
 712 static int nft_meta_get_offload(struct nft_offload_ctx *ctx,
 713                                 struct nft_flow_rule *flow,
 714                                 const struct nft_expr *expr)
 715 {
 716         const struct nft_meta *priv = nft_expr_priv(expr);
 717         struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
 718
 719         switch (priv->key) {
 720         case NFT_META_PROTOCOL:
 721                 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
 722                                         sizeof(__u16), reg);
 723                 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 724                 break;
 725         case NFT_META_L4PROTO:
 726                 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
 727                                         sizeof(__u8), reg);
 728                 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
 729                 break;
 730         case NFT_META_IIF:
 731                 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
 732                                         ingress_ifindex, sizeof(__u32), reg);
 733                 break;
 734         case NFT_META_IIFTYPE:
 735                 NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
 736                                         ingress_iftype, sizeof(__u16), reg);
 737                 break;
 738         default:
 739                 return -EOPNOTSUPP;
 740         }
 741
 742         return 0;
 743 }
 744
 745 bool nft_meta_get_reduce(struct nft_regs_track *track,
 746                          const struct nft_expr *expr)
 747 {
 748         const struct nft_meta *priv = nft_expr_priv(expr);
 749         const struct nft_meta *meta;
 750
 751         if (!nft_reg_track_cmp(track, expr, priv->dreg)) {
 752                 nft_reg_track_update(track, expr, priv->dreg, priv->len);
 753                 return false;
 754         }
 755
 756         meta = nft_expr_priv(track->regs[priv->dreg].selector);
 757         if (priv->key != meta->key ||
 758             priv->dreg != meta->dreg) {
 759                 nft_reg_track_update(track, expr, priv->dreg, priv->len);
 760                 return false;
 761         }
 762
 763         if (!track->regs[priv->dreg].bitwise)
 764                 return true;
 765
 766         return nft_expr_reduce_bitwise(track, expr);
 767 }
 768 EXPORT_SYMBOL_GPL(nft_meta_get_reduce);
 769
 770 static const struct nft_expr_ops nft_meta_get_ops = {
 771         .type           = &nft_meta_type,
 772         .size           = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
 773         .eval           = nft_meta_get_eval,
 774         .init           = nft_meta_get_init,
 775         .dump           = nft_meta_get_dump,
 776         .reduce         = nft_meta_get_reduce,
 777         .validate       = nft_meta_get_validate,
 778         .offload        = nft_meta_get_offload,
 779 };
 780
 781 static bool nft_meta_set_reduce(struct nft_regs_track *track,
 782                                 const struct nft_expr *expr)
 783 {
 784         int i;
 785
 786         for (i = 0; i < NFT_REG32_NUM; i++) {
 787                 if (!track->regs[i].selector)
 788                         continue;
 789
 790                 if (track->regs[i].selector->ops != &nft_meta_get_ops)
 791                         continue;
 792
 793                 __nft_reg_track_cancel(track, i);
 794         }
 795
 796         return false;
 797 }
 798
 799 static const struct nft_expr_ops nft_meta_set_ops = {
 800         .type           = &nft_meta_type,
 801         .size           = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
 802         .eval           = nft_meta_set_eval,
 803         .init           = nft_meta_set_init,
 804         .destroy        = nft_meta_set_destroy,
 805         .dump           = nft_meta_set_dump,
 806         .reduce         = nft_meta_set_reduce,
 807         .validate       = nft_meta_set_validate,
 808 };
 809
 810 static const struct nft_expr_ops *
 811 nft_meta_select_ops(const struct nft_ctx *ctx,
 812                     const struct nlattr * const tb[])
 813 {
 814         if (tb[NFTA_META_KEY] == NULL)
 815                 return ERR_PTR(-EINVAL);
 816
 817         if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
 818                 return ERR_PTR(-EINVAL);
 819
 820 #if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE) && IS_MODULE(CONFIG_NFT_BRIDGE_META)
 821         if (ctx->family == NFPROTO_BRIDGE)
 822                 return ERR_PTR(-EAGAIN);
 823 #endif
 824         if (tb[NFTA_META_DREG])
 825                 return &nft_meta_get_ops;
 826
 827         if (tb[NFTA_META_SREG])
 828                 return &nft_meta_set_ops;
 829
 830         return ERR_PTR(-EINVAL);
 831 }
 832
 833 static int nft_meta_inner_init(const struct nft_ctx *ctx,
 834                                const struct nft_expr *expr,
 835                                const struct nlattr * const tb[])
 836 {
 837         struct nft_meta *priv = nft_expr_priv(expr);
 838         unsigned int len;
 839
 840         if (!tb[NFTA_META_KEY] || !tb[NFTA_META_DREG])
 841                 return -EINVAL;
 842
 843         priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
 844         switch (priv->key) {
 845         case NFT_META_PROTOCOL:
 846                 len = sizeof(u16);
 847                 break;
 848         case NFT_META_L4PROTO:
 849                 len = sizeof(u32);
 850                 break;
 851         default:
 852                 return -EOPNOTSUPP;
 853         }
 854         priv->len = len;
 855
 856         return nft_parse_register_store(ctx, tb[NFTA_META_DREG], &priv->dreg,
 857                                         NULL, NFT_DATA_VALUE, len);
 858 }
 859
 860 void nft_meta_inner_eval(const struct nft_expr *expr,
 861                          struct nft_regs *regs,
 862                          const struct nft_pktinfo *pkt,
 863                          struct nft_inner_tun_ctx *tun_ctx)
 864 {
 865         const struct nft_meta *priv = nft_expr_priv(expr);
 866         u32 *dest = &regs->data[priv->dreg];
 867
 868         switch (priv->key) {
 869         case NFT_META_PROTOCOL:
 870                 nft_reg_store16(dest, (__force u16)tun_ctx->llproto);
 871                 break;
 872         case NFT_META_L4PROTO:
 873                 if (!(tun_ctx->flags & NFT_PAYLOAD_CTX_INNER_TH))
 874                         goto err;
 875
 876                 nft_reg_store8(dest, tun_ctx->l4proto);
 877                 break;
 878         default:
 879                 WARN_ON_ONCE(1);
 880                 goto err;
 881         }
 882         return;
 883
 884 err:
 885         regs->verdict.code = NFT_BREAK;
 886 }
 887 EXPORT_SYMBOL_GPL(nft_meta_inner_eval);
 888
 889 static const struct nft_expr_ops nft_meta_inner_ops = {
 890         .type           = &nft_meta_type,
 891         .size           = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
 892         .init           = nft_meta_inner_init,
 893         .dump           = nft_meta_get_dump,
 894         /* direct call to nft_meta_inner_eval(). */
 895 };
 896
 897 struct nft_expr_type nft_meta_type __read_mostly = {
 898         .name           = "meta",
 899         .select_ops     = nft_meta_select_ops,
 900         .inner_ops      = &nft_meta_inner_ops,
 901         .policy         = nft_meta_policy,
 902         .maxattr        = NFTA_META_MAX,
 903         .owner          = THIS_MODULE,
 904 };
 905
 906 #ifdef CONFIG_NETWORK_SECMARK
 907 struct nft_secmark {
 908         u32 secid;
 909         char *ctx;
 910 };
 911
 912 static const struct nla_policy nft_secmark_policy[NFTA_SECMARK_MAX + 1] = {
 913         [NFTA_SECMARK_CTX]     = { .type = NLA_STRING, .len = NFT_SECMARK_CTX_MAXLEN },
 914 };
 915
 916 static int nft_secmark_compute_secid(struct nft_secmark *priv)
 917 {
 918         u32 tmp_secid = 0;
 919         int err;
 920
 921         err = security_secctx_to_secid(priv->ctx, strlen(priv->ctx), &tmp_secid);
 922         if (err)
 923                 return err;
 924
 925         if (!tmp_secid)
 926                 return -ENOENT;
 927
 928         err = security_secmark_relabel_packet(tmp_secid);
 929         if (err)
 930                 return err;
 931
 932         priv->secid = tmp_secid;
 933         return 0;
 934 }
 935
 936 static void nft_secmark_obj_eval(struct nft_object *obj, struct nft_regs *regs,
 937                                  const struct nft_pktinfo *pkt)
 938 {
 939         const struct nft_secmark *priv = nft_obj_data(obj);
 940         struct sk_buff *skb = pkt->skb;
 941
 942         skb->secmark = priv->secid;
 943 }
 944
 945 static int nft_secmark_obj_init(const struct nft_ctx *ctx,
 946                                 const struct nlattr * const tb[],
 947                                 struct nft_object *obj)
 948 {
 949         struct nft_secmark *priv = nft_obj_data(obj);
 950         int err;
 951
 952         if (tb[NFTA_SECMARK_CTX] == NULL)
 953                 return -EINVAL;
 954
 955         priv->ctx = nla_strdup(tb[NFTA_SECMARK_CTX], GFP_KERNEL_ACCOUNT);
 956         if (!priv->ctx)
 957                 return -ENOMEM;
 958
 959         err = nft_secmark_compute_secid(priv);
 960         if (err) {
 961                 kfree(priv->ctx);
 962                 return err;
 963         }
 964
 965         security_secmark_refcount_inc();
 966
 967         return 0;
 968 }
 969
 970 static int nft_secmark_obj_dump(struct sk_buff *skb, struct nft_object *obj,
 971                                 bool reset)
 972 {
 973         struct nft_secmark *priv = nft_obj_data(obj);
 974         int err;
 975
 976         if (nla_put_string(skb, NFTA_SECMARK_CTX, priv->ctx))
 977                 return -1;
 978
 979         if (reset) {
 980                 err = nft_secmark_compute_secid(priv);
 981                 if (err)
 982                         return err;
 983         }
 984
 985         return 0;
 986 }
 987
 988 static void nft_secmark_obj_destroy(const struct nft_ctx *ctx, struct nft_object *obj)
 989 {
 990         struct nft_secmark *priv = nft_obj_data(obj);
 991
 992         security_secmark_refcount_dec();
 993
 994         kfree(priv->ctx);
 995 }
 996
 997 static const struct nft_object_ops nft_secmark_obj_ops = {
 998         .type           = &nft_secmark_obj_type,
 999         .size           = sizeof(struct nft_secmark),
1000         .init           = nft_secmark_obj_init,
1001         .eval           = nft_secmark_obj_eval,
1002         .dump           = nft_secmark_obj_dump,
1003         .destroy        = nft_secmark_obj_destroy,
1004 };
1005 struct nft_object_type nft_secmark_obj_type __read_mostly = {
1006         .type           = NFT_OBJECT_SECMARK,
1007         .ops            = &nft_secmark_obj_ops,
1008         .maxattr        = NFTA_SECMARK_MAX,
1009         .policy         = nft_secmark_policy,
1010         .owner          = THIS_MODULE,
1011 };
1012 #endif /* CONFIG_NETWORK_SECMARK */