linux/include/net/netfilter/nf_tables.h
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   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _NET_NF_TABLES_H
   3#define _NET_NF_TABLES_H
   4
   5#include <asm/unaligned.h>
   6#include <linux/list.h>
   7#include <linux/netfilter.h>
   8#include <linux/netfilter/nfnetlink.h>
   9#include <linux/netfilter/x_tables.h>
  10#include <linux/netfilter/nf_tables.h>
  11#include <linux/u64_stats_sync.h>
  12#include <linux/rhashtable.h>
  13#include <net/netfilter/nf_flow_table.h>
  14#include <net/netlink.h>
  15#include <net/flow_offload.h>
  16#include <net/netns/generic.h>
  17
  18#define NFT_MAX_HOOKS   (NF_INET_INGRESS + 1)
  19
  20struct module;
  21
  22#define NFT_JUMP_STACK_SIZE     16
  23
  24struct nft_pktinfo {
  25        struct sk_buff                  *skb;
  26        const struct nf_hook_state      *state;
  27        bool                            tprot_set;
  28        u8                              tprot;
  29        u16                             fragoff;
  30        unsigned int                    thoff;
  31};
  32
  33static inline struct sock *nft_sk(const struct nft_pktinfo *pkt)
  34{
  35        return pkt->state->sk;
  36}
  37
  38static inline unsigned int nft_thoff(const struct nft_pktinfo *pkt)
  39{
  40        return pkt->thoff;
  41}
  42
  43static inline struct net *nft_net(const struct nft_pktinfo *pkt)
  44{
  45        return pkt->state->net;
  46}
  47
  48static inline unsigned int nft_hook(const struct nft_pktinfo *pkt)
  49{
  50        return pkt->state->hook;
  51}
  52
  53static inline u8 nft_pf(const struct nft_pktinfo *pkt)
  54{
  55        return pkt->state->pf;
  56}
  57
  58static inline const struct net_device *nft_in(const struct nft_pktinfo *pkt)
  59{
  60        return pkt->state->in;
  61}
  62
  63static inline const struct net_device *nft_out(const struct nft_pktinfo *pkt)
  64{
  65        return pkt->state->out;
  66}
  67
  68static inline void nft_set_pktinfo(struct nft_pktinfo *pkt,
  69                                   struct sk_buff *skb,
  70                                   const struct nf_hook_state *state)
  71{
  72        pkt->skb = skb;
  73        pkt->state = state;
  74}
  75
  76static inline void nft_set_pktinfo_unspec(struct nft_pktinfo *pkt)
  77{
  78        pkt->tprot_set = false;
  79        pkt->tprot = 0;
  80        pkt->thoff = 0;
  81        pkt->fragoff = 0;
  82}
  83
  84/**
  85 *      struct nft_verdict - nf_tables verdict
  86 *
  87 *      @code: nf_tables/netfilter verdict code
  88 *      @chain: destination chain for NFT_JUMP/NFT_GOTO
  89 */
  90struct nft_verdict {
  91        u32                             code;
  92        struct nft_chain                *chain;
  93};
  94
  95struct nft_data {
  96        union {
  97                u32                     data[4];
  98                struct nft_verdict      verdict;
  99        };
 100} __attribute__((aligned(__alignof__(u64))));
 101
 102/**
 103 *      struct nft_regs - nf_tables register set
 104 *
 105 *      @data: data registers
 106 *      @verdict: verdict register
 107 *
 108 *      The first four data registers alias to the verdict register.
 109 */
 110struct nft_regs {
 111        union {
 112                u32                     data[20];
 113                struct nft_verdict      verdict;
 114        };
 115};
 116
 117/* Store/load an u8, u16 or u64 integer to/from the u32 data register.
 118 *
 119 * Note, when using concatenations, register allocation happens at 32-bit
 120 * level. So for store instruction, pad the rest part with zero to avoid
 121 * garbage values.
 122 */
 123
 124static inline void nft_reg_store8(u32 *dreg, u8 val)
 125{
 126        *dreg = 0;
 127        *(u8 *)dreg = val;
 128}
 129
 130static inline u8 nft_reg_load8(const u32 *sreg)
 131{
 132        return *(u8 *)sreg;
 133}
 134
 135static inline void nft_reg_store16(u32 *dreg, u16 val)
 136{
 137        *dreg = 0;
 138        *(u16 *)dreg = val;
 139}
 140
 141static inline u16 nft_reg_load16(const u32 *sreg)
 142{
 143        return *(u16 *)sreg;
 144}
 145
 146static inline void nft_reg_store64(u32 *dreg, u64 val)
 147{
 148        put_unaligned(val, (u64 *)dreg);
 149}
 150
 151static inline u64 nft_reg_load64(const u32 *sreg)
 152{
 153        return get_unaligned((u64 *)sreg);
 154}
 155
 156static inline void nft_data_copy(u32 *dst, const struct nft_data *src,
 157                                 unsigned int len)
 158{
 159        if (len % NFT_REG32_SIZE)
 160                dst[len / NFT_REG32_SIZE] = 0;
 161        memcpy(dst, src, len);
 162}
 163
 164/**
 165 *      struct nft_ctx - nf_tables rule/set context
 166 *
 167 *      @net: net namespace
 168 *      @table: the table the chain is contained in
 169 *      @chain: the chain the rule is contained in
 170 *      @nla: netlink attributes
 171 *      @portid: netlink portID of the original message
 172 *      @seq: netlink sequence number
 173 *      @family: protocol family
 174 *      @level: depth of the chains
 175 *      @report: notify via unicast netlink message
 176 */
 177struct nft_ctx {
 178        struct net                      *net;
 179        struct nft_table                *table;
 180        struct nft_chain                *chain;
 181        const struct nlattr * const     *nla;
 182        u32                             portid;
 183        u32                             seq;
 184        u16                             flags;
 185        u8                              family;
 186        u8                              level;
 187        bool                            report;
 188};
 189
 190struct nft_data_desc {
 191        enum nft_data_types             type;
 192        unsigned int                    len;
 193};
 194
 195int nft_data_init(const struct nft_ctx *ctx,
 196                  struct nft_data *data, unsigned int size,
 197                  struct nft_data_desc *desc, const struct nlattr *nla);
 198void nft_data_hold(const struct nft_data *data, enum nft_data_types type);
 199void nft_data_release(const struct nft_data *data, enum nft_data_types type);
 200int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
 201                  enum nft_data_types type, unsigned int len);
 202
 203static inline enum nft_data_types nft_dreg_to_type(enum nft_registers reg)
 204{
 205        return reg == NFT_REG_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
 206}
 207
 208static inline enum nft_registers nft_type_to_reg(enum nft_data_types type)
 209{
 210        return type == NFT_DATA_VERDICT ? NFT_REG_VERDICT : NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE;
 211}
 212
 213int nft_parse_u32_check(const struct nlattr *attr, int max, u32 *dest);
 214int nft_dump_register(struct sk_buff *skb, unsigned int attr, unsigned int reg);
 215
 216int nft_parse_register_load(const struct nlattr *attr, u8 *sreg, u32 len);
 217int nft_parse_register_store(const struct nft_ctx *ctx,
 218                             const struct nlattr *attr, u8 *dreg,
 219                             const struct nft_data *data,
 220                             enum nft_data_types type, unsigned int len);
 221
 222/**
 223 *      struct nft_userdata - user defined data associated with an object
 224 *
 225 *      @len: length of the data
 226 *      @data: content
 227 *
 228 *      The presence of user data is indicated in an object specific fashion,
 229 *      so a length of zero can't occur and the value "len" indicates data
 230 *      of length len + 1.
 231 */
 232struct nft_userdata {
 233        u8                      len;
 234        unsigned char           data[];
 235};
 236
 237/**
 238 *      struct nft_set_elem - generic representation of set elements
 239 *
 240 *      @key: element key
 241 *      @key_end: closing element key
 242 *      @priv: element private data and extensions
 243 */
 244struct nft_set_elem {
 245        union {
 246                u32             buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
 247                struct nft_data val;
 248        } key;
 249        union {
 250                u32             buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
 251                struct nft_data val;
 252        } key_end;
 253        union {
 254                u32             buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
 255                struct nft_data val;
 256        } data;
 257        void                    *priv;
 258};
 259
 260struct nft_set;
 261struct nft_set_iter {
 262        u8              genmask;
 263        unsigned int    count;
 264        unsigned int    skip;
 265        int             err;
 266        int             (*fn)(const struct nft_ctx *ctx,
 267                              struct nft_set *set,
 268                              const struct nft_set_iter *iter,
 269                              struct nft_set_elem *elem);
 270};
 271
 272/**
 273 *      struct nft_set_desc - description of set elements
 274 *
 275 *      @klen: key length
 276 *      @dlen: data length
 277 *      @size: number of set elements
 278 *      @field_len: length of each field in concatenation, bytes
 279 *      @field_count: number of concatenated fields in element
 280 *      @expr: set must support for expressions
 281 */
 282struct nft_set_desc {
 283        unsigned int            klen;
 284        unsigned int            dlen;
 285        unsigned int            size;
 286        u8                      field_len[NFT_REG32_COUNT];
 287        u8                      field_count;
 288        bool                    expr;
 289};
 290
 291/**
 292 *      enum nft_set_class - performance class
 293 *
 294 *      @NFT_LOOKUP_O_1: constant, O(1)
 295 *      @NFT_LOOKUP_O_LOG_N: logarithmic, O(log N)
 296 *      @NFT_LOOKUP_O_N: linear, O(N)
 297 */
 298enum nft_set_class {
 299        NFT_SET_CLASS_O_1,
 300        NFT_SET_CLASS_O_LOG_N,
 301        NFT_SET_CLASS_O_N,
 302};
 303
 304/**
 305 *      struct nft_set_estimate - estimation of memory and performance
 306 *                                characteristics
 307 *
 308 *      @size: required memory
 309 *      @lookup: lookup performance class
 310 *      @space: memory class
 311 */
 312struct nft_set_estimate {
 313        u64                     size;
 314        enum nft_set_class      lookup;
 315        enum nft_set_class      space;
 316};
 317
 318#define NFT_EXPR_MAXATTR                16
 319#define NFT_EXPR_SIZE(size)             (sizeof(struct nft_expr) + \
 320                                         ALIGN(size, __alignof__(struct nft_expr)))
 321
 322/**
 323 *      struct nft_expr - nf_tables expression
 324 *
 325 *      @ops: expression ops
 326 *      @data: expression private data
 327 */
 328struct nft_expr {
 329        const struct nft_expr_ops       *ops;
 330        unsigned char                   data[]
 331                __attribute__((aligned(__alignof__(u64))));
 332};
 333
 334static inline void *nft_expr_priv(const struct nft_expr *expr)
 335{
 336        return (void *)expr->data;
 337}
 338
 339int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src);
 340void nft_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr);
 341int nft_expr_dump(struct sk_buff *skb, unsigned int attr,
 342                  const struct nft_expr *expr);
 343
 344struct nft_set_ext;
 345
 346/**
 347 *      struct nft_set_ops - nf_tables set operations
 348 *
 349 *      @lookup: look up an element within the set
 350 *      @update: update an element if exists, add it if doesn't exist
 351 *      @delete: delete an element
 352 *      @insert: insert new element into set
 353 *      @activate: activate new element in the next generation
 354 *      @deactivate: lookup for element and deactivate it in the next generation
 355 *      @flush: deactivate element in the next generation
 356 *      @remove: remove element from set
 357 *      @walk: iterate over all set elements
 358 *      @get: get set elements
 359 *      @privsize: function to return size of set private data
 360 *      @init: initialize private data of new set instance
 361 *      @destroy: destroy private data of set instance
 362 *      @elemsize: element private size
 363 *
 364 *      Operations lookup, update and delete have simpler interfaces, are faster
 365 *      and currently only used in the packet path. All the rest are slower,
 366 *      control plane functions.
 367 */
 368struct nft_set_ops {
 369        bool                            (*lookup)(const struct net *net,
 370                                                  const struct nft_set *set,
 371                                                  const u32 *key,
 372                                                  const struct nft_set_ext **ext);
 373        bool                            (*update)(struct nft_set *set,
 374                                                  const u32 *key,
 375                                                  void *(*new)(struct nft_set *,
 376                                                               const struct nft_expr *,
 377                                                               struct nft_regs *),
 378                                                  const struct nft_expr *expr,
 379                                                  struct nft_regs *regs,
 380                                                  const struct nft_set_ext **ext);
 381        bool                            (*delete)(const struct nft_set *set,
 382                                                  const u32 *key);
 383
 384        int                             (*insert)(const struct net *net,
 385                                                  const struct nft_set *set,
 386                                                  const struct nft_set_elem *elem,
 387                                                  struct nft_set_ext **ext);
 388        void                            (*activate)(const struct net *net,
 389                                                    const struct nft_set *set,
 390                                                    const struct nft_set_elem *elem);
 391        void *                          (*deactivate)(const struct net *net,
 392                                                      const struct nft_set *set,
 393                                                      const struct nft_set_elem *elem);
 394        bool                            (*flush)(const struct net *net,
 395                                                 const struct nft_set *set,
 396                                                 void *priv);
 397        void                            (*remove)(const struct net *net,
 398                                                  const struct nft_set *set,
 399                                                  const struct nft_set_elem *elem);
 400        void                            (*walk)(const struct nft_ctx *ctx,
 401                                                struct nft_set *set,
 402                                                struct nft_set_iter *iter);
 403        void *                          (*get)(const struct net *net,
 404                                               const struct nft_set *set,
 405                                               const struct nft_set_elem *elem,
 406                                               unsigned int flags);
 407
 408        u64                             (*privsize)(const struct nlattr * const nla[],
 409                                                    const struct nft_set_desc *desc);
 410        bool                            (*estimate)(const struct nft_set_desc *desc,
 411                                                    u32 features,
 412                                                    struct nft_set_estimate *est);
 413        int                             (*init)(const struct nft_set *set,
 414                                                const struct nft_set_desc *desc,
 415                                                const struct nlattr * const nla[]);
 416        void                            (*destroy)(const struct nft_set *set);
 417        void                            (*gc_init)(const struct nft_set *set);
 418
 419        unsigned int                    elemsize;
 420};
 421
 422/**
 423 *      struct nft_set_type - nf_tables set type
 424 *
 425 *      @ops: set ops for this type
 426 *      @features: features supported by the implementation
 427 */
 428struct nft_set_type {
 429        const struct nft_set_ops        ops;
 430        u32                             features;
 431};
 432#define to_set_type(o) container_of(o, struct nft_set_type, ops)
 433
 434struct nft_set_elem_expr {
 435        u8                              size;
 436        unsigned char                   data[]
 437                __attribute__((aligned(__alignof__(struct nft_expr))));
 438};
 439
 440#define nft_setelem_expr_at(__elem_expr, __offset)                      \
 441        ((struct nft_expr *)&__elem_expr->data[__offset])
 442
 443#define nft_setelem_expr_foreach(__expr, __elem_expr, __size)           \
 444        for (__expr = nft_setelem_expr_at(__elem_expr, 0), __size = 0;  \
 445             __size < (__elem_expr)->size;                              \
 446             __size += (__expr)->ops->size, __expr = ((void *)(__expr)) + (__expr)->ops->size)
 447
 448#define NFT_SET_EXPR_MAX        2
 449
 450/**
 451 *      struct nft_set - nf_tables set instance
 452 *
 453 *      @list: table set list node
 454 *      @bindings: list of set bindings
 455 *      @table: table this set belongs to
 456 *      @net: netnamespace this set belongs to
 457 *      @name: name of the set
 458 *      @handle: unique handle of the set
 459 *      @ktype: key type (numeric type defined by userspace, not used in the kernel)
 460 *      @dtype: data type (verdict or numeric type defined by userspace)
 461 *      @objtype: object type (see NFT_OBJECT_* definitions)
 462 *      @size: maximum set size
 463 *      @field_len: length of each field in concatenation, bytes
 464 *      @field_count: number of concatenated fields in element
 465 *      @use: number of rules references to this set
 466 *      @nelems: number of elements
 467 *      @ndeact: number of deactivated elements queued for removal
 468 *      @timeout: default timeout value in jiffies
 469 *      @gc_int: garbage collection interval in msecs
 470 *      @policy: set parameterization (see enum nft_set_policies)
 471 *      @udlen: user data length
 472 *      @udata: user data
 473 *      @expr: stateful expression
 474 *      @ops: set ops
 475 *      @flags: set flags
 476 *      @genmask: generation mask
 477 *      @klen: key length
 478 *      @dlen: data length
 479 *      @data: private set data
 480 */
 481struct nft_set {
 482        struct list_head                list;
 483        struct list_head                bindings;
 484        struct nft_table                *table;
 485        possible_net_t                  net;
 486        char                            *name;
 487        u64                             handle;
 488        u32                             ktype;
 489        u32                             dtype;
 490        u32                             objtype;
 491        u32                             size;
 492        u8                              field_len[NFT_REG32_COUNT];
 493        u8                              field_count;
 494        u32                             use;
 495        atomic_t                        nelems;
 496        u32                             ndeact;
 497        u64                             timeout;
 498        u32                             gc_int;
 499        u16                             policy;
 500        u16                             udlen;
 501        unsigned char                   *udata;
 502        /* runtime data below here */
 503        const struct nft_set_ops        *ops ____cacheline_aligned;
 504        u16                             flags:14,
 505                                        genmask:2;
 506        u8                              klen;
 507        u8                              dlen;
 508        u8                              num_exprs;
 509        struct nft_expr                 *exprs[NFT_SET_EXPR_MAX];
 510        struct list_head                catchall_list;
 511        unsigned char                   data[]
 512                __attribute__((aligned(__alignof__(u64))));
 513};
 514
 515static inline bool nft_set_is_anonymous(const struct nft_set *set)
 516{
 517        return set->flags & NFT_SET_ANONYMOUS;
 518}
 519
 520static inline void *nft_set_priv(const struct nft_set *set)
 521{
 522        return (void *)set->data;
 523}
 524
 525static inline struct nft_set *nft_set_container_of(const void *priv)
 526{
 527        return (void *)priv - offsetof(struct nft_set, data);
 528}
 529
 530struct nft_set *nft_set_lookup_global(const struct net *net,
 531                                      const struct nft_table *table,
 532                                      const struct nlattr *nla_set_name,
 533                                      const struct nlattr *nla_set_id,
 534                                      u8 genmask);
 535
 536struct nft_set_ext *nft_set_catchall_lookup(const struct net *net,
 537                                            const struct nft_set *set);
 538void *nft_set_catchall_gc(const struct nft_set *set);
 539
 540static inline unsigned long nft_set_gc_interval(const struct nft_set *set)
 541{
 542        return set->gc_int ? msecs_to_jiffies(set->gc_int) : HZ;
 543}
 544
 545/**
 546 *      struct nft_set_binding - nf_tables set binding
 547 *
 548 *      @list: set bindings list node
 549 *      @chain: chain containing the rule bound to the set
 550 *      @flags: set action flags
 551 *
 552 *      A set binding contains all information necessary for validation
 553 *      of new elements added to a bound set.
 554 */
 555struct nft_set_binding {
 556        struct list_head                list;
 557        const struct nft_chain          *chain;
 558        u32                             flags;
 559};
 560
 561enum nft_trans_phase;
 562void nf_tables_deactivate_set(const struct nft_ctx *ctx, struct nft_set *set,
 563                              struct nft_set_binding *binding,
 564                              enum nft_trans_phase phase);
 565int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
 566                       struct nft_set_binding *binding);
 567void nf_tables_destroy_set(const struct nft_ctx *ctx, struct nft_set *set);
 568
 569/**
 570 *      enum nft_set_extensions - set extension type IDs
 571 *
 572 *      @NFT_SET_EXT_KEY: element key
 573 *      @NFT_SET_EXT_KEY_END: upper bound element key, for ranges
 574 *      @NFT_SET_EXT_DATA: mapping data
 575 *      @NFT_SET_EXT_FLAGS: element flags
 576 *      @NFT_SET_EXT_TIMEOUT: element timeout
 577 *      @NFT_SET_EXT_EXPIRATION: element expiration time
 578 *      @NFT_SET_EXT_USERDATA: user data associated with the element
 579 *      @NFT_SET_EXT_EXPRESSIONS: expressions assiciated with the element
 580 *      @NFT_SET_EXT_OBJREF: stateful object reference associated with element
 581 *      @NFT_SET_EXT_NUM: number of extension types
 582 */
 583enum nft_set_extensions {
 584        NFT_SET_EXT_KEY,
 585        NFT_SET_EXT_KEY_END,
 586        NFT_SET_EXT_DATA,
 587        NFT_SET_EXT_FLAGS,
 588        NFT_SET_EXT_TIMEOUT,
 589        NFT_SET_EXT_EXPIRATION,
 590        NFT_SET_EXT_USERDATA,
 591        NFT_SET_EXT_EXPRESSIONS,
 592        NFT_SET_EXT_OBJREF,
 593        NFT_SET_EXT_NUM
 594};
 595
 596/**
 597 *      struct nft_set_ext_type - set extension type
 598 *
 599 *      @len: fixed part length of the extension
 600 *      @align: alignment requirements of the extension
 601 */
 602struct nft_set_ext_type {
 603        u8      len;
 604        u8      align;
 605};
 606
 607extern const struct nft_set_ext_type nft_set_ext_types[];
 608
 609/**
 610 *      struct nft_set_ext_tmpl - set extension template
 611 *
 612 *      @len: length of extension area
 613 *      @offset: offsets of individual extension types
 614 */
 615struct nft_set_ext_tmpl {
 616        u16     len;
 617        u8      offset[NFT_SET_EXT_NUM];
 618};
 619
 620/**
 621 *      struct nft_set_ext - set extensions
 622 *
 623 *      @genmask: generation mask
 624 *      @offset: offsets of individual extension types
 625 *      @data: beginning of extension data
 626 */
 627struct nft_set_ext {
 628        u8      genmask;
 629        u8      offset[NFT_SET_EXT_NUM];
 630        char    data[];
 631};
 632
 633static inline void nft_set_ext_prepare(struct nft_set_ext_tmpl *tmpl)
 634{
 635        memset(tmpl, 0, sizeof(*tmpl));
 636        tmpl->len = sizeof(struct nft_set_ext);
 637}
 638
 639static inline void nft_set_ext_add_length(struct nft_set_ext_tmpl *tmpl, u8 id,
 640                                          unsigned int len)
 641{
 642        tmpl->len        = ALIGN(tmpl->len, nft_set_ext_types[id].align);
 643        BUG_ON(tmpl->len > U8_MAX);
 644        tmpl->offset[id] = tmpl->len;
 645        tmpl->len       += nft_set_ext_types[id].len + len;
 646}
 647
 648static inline void nft_set_ext_add(struct nft_set_ext_tmpl *tmpl, u8 id)
 649{
 650        nft_set_ext_add_length(tmpl, id, 0);
 651}
 652
 653static inline void nft_set_ext_init(struct nft_set_ext *ext,
 654                                    const struct nft_set_ext_tmpl *tmpl)
 655{
 656        memcpy(ext->offset, tmpl->offset, sizeof(ext->offset));
 657}
 658
 659static inline bool __nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
 660{
 661        return !!ext->offset[id];
 662}
 663
 664static inline bool nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
 665{
 666        return ext && __nft_set_ext_exists(ext, id);
 667}
 668
 669static inline void *nft_set_ext(const struct nft_set_ext *ext, u8 id)
 670{
 671        return (void *)ext + ext->offset[id];
 672}
 673
 674static inline struct nft_data *nft_set_ext_key(const struct nft_set_ext *ext)
 675{
 676        return nft_set_ext(ext, NFT_SET_EXT_KEY);
 677}
 678
 679static inline struct nft_data *nft_set_ext_key_end(const struct nft_set_ext *ext)
 680{
 681        return nft_set_ext(ext, NFT_SET_EXT_KEY_END);
 682}
 683
 684static inline struct nft_data *nft_set_ext_data(const struct nft_set_ext *ext)
 685{
 686        return nft_set_ext(ext, NFT_SET_EXT_DATA);
 687}
 688
 689static inline u8 *nft_set_ext_flags(const struct nft_set_ext *ext)
 690{
 691        return nft_set_ext(ext, NFT_SET_EXT_FLAGS);
 692}
 693
 694static inline u64 *nft_set_ext_timeout(const struct nft_set_ext *ext)
 695{
 696        return nft_set_ext(ext, NFT_SET_EXT_TIMEOUT);
 697}
 698
 699static inline u64 *nft_set_ext_expiration(const struct nft_set_ext *ext)
 700{
 701        return nft_set_ext(ext, NFT_SET_EXT_EXPIRATION);
 702}
 703
 704static inline struct nft_userdata *nft_set_ext_userdata(const struct nft_set_ext *ext)
 705{
 706        return nft_set_ext(ext, NFT_SET_EXT_USERDATA);
 707}
 708
 709static inline struct nft_set_elem_expr *nft_set_ext_expr(const struct nft_set_ext *ext)
 710{
 711        return nft_set_ext(ext, NFT_SET_EXT_EXPRESSIONS);
 712}
 713
 714static inline bool nft_set_elem_expired(const struct nft_set_ext *ext)
 715{
 716        return nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION) &&
 717               time_is_before_eq_jiffies64(*nft_set_ext_expiration(ext));
 718}
 719
 720static inline struct nft_set_ext *nft_set_elem_ext(const struct nft_set *set,
 721                                                   void *elem)
 722{
 723        return elem + set->ops->elemsize;
 724}
 725
 726static inline struct nft_object **nft_set_ext_obj(const struct nft_set_ext *ext)
 727{
 728        return nft_set_ext(ext, NFT_SET_EXT_OBJREF);
 729}
 730
 731struct nft_expr *nft_set_elem_expr_alloc(const struct nft_ctx *ctx,
 732                                         const struct nft_set *set,
 733                                         const struct nlattr *attr);
 734
 735void *nft_set_elem_init(const struct nft_set *set,
 736                        const struct nft_set_ext_tmpl *tmpl,
 737                        const u32 *key, const u32 *key_end, const u32 *data,
 738                        u64 timeout, u64 expiration, gfp_t gfp);
 739int nft_set_elem_expr_clone(const struct nft_ctx *ctx, struct nft_set *set,
 740                            struct nft_expr *expr_array[]);
 741void nft_set_elem_destroy(const struct nft_set *set, void *elem,
 742                          bool destroy_expr);
 743
 744/**
 745 *      struct nft_set_gc_batch_head - nf_tables set garbage collection batch
 746 *
 747 *      @rcu: rcu head
 748 *      @set: set the elements belong to
 749 *      @cnt: count of elements
 750 */
 751struct nft_set_gc_batch_head {
 752        struct rcu_head                 rcu;
 753        const struct nft_set            *set;
 754        unsigned int                    cnt;
 755};
 756
 757#define NFT_SET_GC_BATCH_SIZE   ((PAGE_SIZE -                             \
 758                                  sizeof(struct nft_set_gc_batch_head)) / \
 759                                 sizeof(void *))
 760
 761/**
 762 *      struct nft_set_gc_batch - nf_tables set garbage collection batch
 763 *
 764 *      @head: GC batch head
 765 *      @elems: garbage collection elements
 766 */
 767struct nft_set_gc_batch {
 768        struct nft_set_gc_batch_head    head;
 769        void                            *elems[NFT_SET_GC_BATCH_SIZE];
 770};
 771
 772struct nft_set_gc_batch *nft_set_gc_batch_alloc(const struct nft_set *set,
 773                                                gfp_t gfp);
 774void nft_set_gc_batch_release(struct rcu_head *rcu);
 775
 776static inline void nft_set_gc_batch_complete(struct nft_set_gc_batch *gcb)
 777{
 778        if (gcb != NULL)
 779                call_rcu(&gcb->head.rcu, nft_set_gc_batch_release);
 780}
 781
 782static inline struct nft_set_gc_batch *
 783nft_set_gc_batch_check(const struct nft_set *set, struct nft_set_gc_batch *gcb,
 784                       gfp_t gfp)
 785{
 786        if (gcb != NULL) {
 787                if (gcb->head.cnt + 1 < ARRAY_SIZE(gcb->elems))
 788                        return gcb;
 789                nft_set_gc_batch_complete(gcb);
 790        }
 791        return nft_set_gc_batch_alloc(set, gfp);
 792}
 793
 794static inline void nft_set_gc_batch_add(struct nft_set_gc_batch *gcb,
 795                                        void *elem)
 796{
 797        gcb->elems[gcb->head.cnt++] = elem;
 798}
 799
 800struct nft_expr_ops;
 801/**
 802 *      struct nft_expr_type - nf_tables expression type
 803 *
 804 *      @select_ops: function to select nft_expr_ops
 805 *      @release_ops: release nft_expr_ops
 806 *      @ops: default ops, used when no select_ops functions is present
 807 *      @list: used internally
 808 *      @name: Identifier
 809 *      @owner: module reference
 810 *      @policy: netlink attribute policy
 811 *      @maxattr: highest netlink attribute number
 812 *      @family: address family for AF-specific types
 813 *      @flags: expression type flags
 814 */
 815struct nft_expr_type {
 816        const struct nft_expr_ops       *(*select_ops)(const struct nft_ctx *,
 817                                                       const struct nlattr * const tb[]);
 818        void                            (*release_ops)(const struct nft_expr_ops *ops);
 819        const struct nft_expr_ops       *ops;
 820        struct list_head                list;
 821        const char                      *name;
 822        struct module                   *owner;
 823        const struct nla_policy         *policy;
 824        unsigned int                    maxattr;
 825        u8                              family;
 826        u8                              flags;
 827};
 828
 829#define NFT_EXPR_STATEFUL               0x1
 830#define NFT_EXPR_GC                     0x2
 831
 832enum nft_trans_phase {
 833        NFT_TRANS_PREPARE,
 834        NFT_TRANS_ABORT,
 835        NFT_TRANS_COMMIT,
 836        NFT_TRANS_RELEASE
 837};
 838
 839struct nft_flow_rule;
 840struct nft_offload_ctx;
 841
 842/**
 843 *      struct nft_expr_ops - nf_tables expression operations
 844 *
 845 *      @eval: Expression evaluation function
 846 *      @size: full expression size, including private data size
 847 *      @init: initialization function
 848 *      @activate: activate expression in the next generation
 849 *      @deactivate: deactivate expression in next generation
 850 *      @destroy: destruction function, called after synchronize_rcu
 851 *      @dump: function to dump parameters
 852 *      @type: expression type
 853 *      @validate: validate expression, called during loop detection
 854 *      @data: extra data to attach to this expression operation
 855 */
 856struct nft_expr_ops {
 857        void                            (*eval)(const struct nft_expr *expr,
 858                                                struct nft_regs *regs,
 859                                                const struct nft_pktinfo *pkt);
 860        int                             (*clone)(struct nft_expr *dst,
 861                                                 const struct nft_expr *src);
 862        unsigned int                    size;
 863
 864        int                             (*init)(const struct nft_ctx *ctx,
 865                                                const struct nft_expr *expr,
 866                                                const struct nlattr * const tb[]);
 867        void                            (*activate)(const struct nft_ctx *ctx,
 868                                                    const struct nft_expr *expr);
 869        void                            (*deactivate)(const struct nft_ctx *ctx,
 870                                                      const struct nft_expr *expr,
 871                                                      enum nft_trans_phase phase);
 872        void                            (*destroy)(const struct nft_ctx *ctx,
 873                                                   const struct nft_expr *expr);
 874        void                            (*destroy_clone)(const struct nft_ctx *ctx,
 875                                                         const struct nft_expr *expr);
 876        int                             (*dump)(struct sk_buff *skb,
 877                                                const struct nft_expr *expr);
 878        int                             (*validate)(const struct nft_ctx *ctx,
 879                                                    const struct nft_expr *expr,
 880                                                    const struct nft_data **data);
 881        bool                            (*gc)(struct net *net,
 882                                              const struct nft_expr *expr);
 883        int                             (*offload)(struct nft_offload_ctx *ctx,
 884                                                   struct nft_flow_rule *flow,
 885                                                   const struct nft_expr *expr);
 886        void                            (*offload_stats)(struct nft_expr *expr,
 887                                                         const struct flow_stats *stats);
 888        u32                             offload_flags;
 889        const struct nft_expr_type      *type;
 890        void                            *data;
 891};
 892
 893/**
 894 *      struct nft_rule - nf_tables rule
 895 *
 896 *      @list: used internally
 897 *      @handle: rule handle
 898 *      @genmask: generation mask
 899 *      @dlen: length of expression data
 900 *      @udata: user data is appended to the rule
 901 *      @data: expression data
 902 */
 903struct nft_rule {
 904        struct list_head                list;
 905        u64                             handle:42,
 906                                        genmask:2,
 907                                        dlen:12,
 908                                        udata:1;
 909        unsigned char                   data[]
 910                __attribute__((aligned(__alignof__(struct nft_expr))));
 911};
 912
 913static inline struct nft_expr *nft_expr_first(const struct nft_rule *rule)
 914{
 915        return (struct nft_expr *)&rule->data[0];
 916}
 917
 918static inline struct nft_expr *nft_expr_next(const struct nft_expr *expr)
 919{
 920        return ((void *)expr) + expr->ops->size;
 921}
 922
 923static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule)
 924{
 925        return (struct nft_expr *)&rule->data[rule->dlen];
 926}
 927
 928static inline bool nft_expr_more(const struct nft_rule *rule,
 929                                 const struct nft_expr *expr)
 930{
 931        return expr != nft_expr_last(rule) && expr->ops;
 932}
 933
 934static inline struct nft_userdata *nft_userdata(const struct nft_rule *rule)
 935{
 936        return (void *)&rule->data[rule->dlen];
 937}
 938
 939void nf_tables_rule_release(const struct nft_ctx *ctx, struct nft_rule *rule);
 940
 941static inline void nft_set_elem_update_expr(const struct nft_set_ext *ext,
 942                                            struct nft_regs *regs,
 943                                            const struct nft_pktinfo *pkt)
 944{
 945        struct nft_set_elem_expr *elem_expr;
 946        struct nft_expr *expr;
 947        u32 size;
 948
 949        if (__nft_set_ext_exists(ext, NFT_SET_EXT_EXPRESSIONS)) {
 950                elem_expr = nft_set_ext_expr(ext);
 951                nft_setelem_expr_foreach(expr, elem_expr, size) {
 952                        expr->ops->eval(expr, regs, pkt);
 953                        if (regs->verdict.code == NFT_BREAK)
 954                                return;
 955                }
 956        }
 957}
 958
 959/*
 960 * The last pointer isn't really necessary, but the compiler isn't able to
 961 * determine that the result of nft_expr_last() is always the same since it
 962 * can't assume that the dlen value wasn't changed within calls in the loop.
 963 */
 964#define nft_rule_for_each_expr(expr, last, rule) \
 965        for ((expr) = nft_expr_first(rule), (last) = nft_expr_last(rule); \
 966             (expr) != (last); \
 967             (expr) = nft_expr_next(expr))
 968
 969#define NFT_CHAIN_POLICY_UNSET          U8_MAX
 970
 971/**
 972 *      struct nft_chain - nf_tables chain
 973 *
 974 *      @rules: list of rules in the chain
 975 *      @list: used internally
 976 *      @rhlhead: used internally
 977 *      @table: table that this chain belongs to
 978 *      @handle: chain handle
 979 *      @use: number of jump references to this chain
 980 *      @flags: bitmask of enum nft_chain_flags
 981 *      @name: name of the chain
 982 */
 983struct nft_chain {
 984        struct nft_rule                 *__rcu *rules_gen_0;
 985        struct nft_rule                 *__rcu *rules_gen_1;
 986        struct list_head                rules;
 987        struct list_head                list;
 988        struct rhlist_head              rhlhead;
 989        struct nft_table                *table;
 990        u64                             handle;
 991        u32                             use;
 992        u8                              flags:5,
 993                                        bound:1,
 994                                        genmask:2;
 995        char                            *name;
 996        u16                             udlen;
 997        u8                              *udata;
 998
 999        /* Only used during control plane commit phase: */
1000        struct nft_rule                 **rules_next;
1001};
1002
1003int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain);
1004
1005enum nft_chain_types {
1006        NFT_CHAIN_T_DEFAULT = 0,
1007        NFT_CHAIN_T_ROUTE,
1008        NFT_CHAIN_T_NAT,
1009        NFT_CHAIN_T_MAX
1010};
1011
1012/**
1013 *      struct nft_chain_type - nf_tables chain type info
1014 *
1015 *      @name: name of the type
1016 *      @type: numeric identifier
1017 *      @family: address family
1018 *      @owner: module owner
1019 *      @hook_mask: mask of valid hooks
1020 *      @hooks: array of hook functions
1021 *      @ops_register: base chain register function
1022 *      @ops_unregister: base chain unregister function
1023 */
1024struct nft_chain_type {
1025        const char                      *name;
1026        enum nft_chain_types            type;
1027        int                             family;
1028        struct module                   *owner;
1029        unsigned int                    hook_mask;
1030        nf_hookfn                       *hooks[NFT_MAX_HOOKS];
1031        int                             (*ops_register)(struct net *net, const struct nf_hook_ops *ops);
1032        void                            (*ops_unregister)(struct net *net, const struct nf_hook_ops *ops);
1033};
1034
1035int nft_chain_validate_dependency(const struct nft_chain *chain,
1036                                  enum nft_chain_types type);
1037int nft_chain_validate_hooks(const struct nft_chain *chain,
1038                             unsigned int hook_flags);
1039
1040static inline bool nft_chain_is_bound(struct nft_chain *chain)
1041{
1042        return (chain->flags & NFT_CHAIN_BINDING) && chain->bound;
1043}
1044
1045void nft_chain_del(struct nft_chain *chain);
1046void nf_tables_chain_destroy(struct nft_ctx *ctx);
1047
1048struct nft_stats {
1049        u64                     bytes;
1050        u64                     pkts;
1051        struct u64_stats_sync   syncp;
1052};
1053
1054struct nft_hook {
1055        struct list_head        list;
1056        bool                    inactive;
1057        struct nf_hook_ops      ops;
1058        struct rcu_head         rcu;
1059};
1060
1061/**
1062 *      struct nft_base_chain - nf_tables base chain
1063 *
1064 *      @ops: netfilter hook ops
1065 *      @hook_list: list of netfilter hooks (for NFPROTO_NETDEV family)
1066 *      @type: chain type
1067 *      @policy: default policy
1068 *      @stats: per-cpu chain stats
1069 *      @chain: the chain
1070 *      @flow_block: flow block (for hardware offload)
1071 */
1072struct nft_base_chain {
1073        struct nf_hook_ops              ops;
1074        struct list_head                hook_list;
1075        const struct nft_chain_type     *type;
1076        u8                              policy;
1077        u8                              flags;
1078        struct nft_stats __percpu       *stats;
1079        struct nft_chain                chain;
1080        struct flow_block               flow_block;
1081};
1082
1083static inline struct nft_base_chain *nft_base_chain(const struct nft_chain *chain)
1084{
1085        return container_of(chain, struct nft_base_chain, chain);
1086}
1087
1088static inline bool nft_is_base_chain(const struct nft_chain *chain)
1089{
1090        return chain->flags & NFT_CHAIN_BASE;
1091}
1092
1093int __nft_release_basechain(struct nft_ctx *ctx);
1094
1095unsigned int nft_do_chain(struct nft_pktinfo *pkt, void *priv);
1096
1097/**
1098 *      struct nft_table - nf_tables table
1099 *
1100 *      @list: used internally
1101 *      @chains_ht: chains in the table
1102 *      @chains: same, for stable walks
1103 *      @sets: sets in the table
1104 *      @objects: stateful objects in the table
1105 *      @flowtables: flow tables in the table
1106 *      @hgenerator: handle generator state
1107 *      @handle: table handle
1108 *      @use: number of chain references to this table
1109 *      @flags: table flag (see enum nft_table_flags)
1110 *      @genmask: generation mask
1111 *      @afinfo: address family info
1112 *      @name: name of the table
1113 */
1114struct nft_table {
1115        struct list_head                list;
1116        struct rhltable                 chains_ht;
1117        struct list_head                chains;
1118        struct list_head                sets;
1119        struct list_head                objects;
1120        struct list_head                flowtables;
1121        u64                             hgenerator;
1122        u64                             handle;
1123        u32                             use;
1124        u16                             family:6,
1125                                        flags:8,
1126                                        genmask:2;
1127        u32                             nlpid;
1128        char                            *name;
1129        u16                             udlen;
1130        u8                              *udata;
1131};
1132
1133static inline bool nft_table_has_owner(const struct nft_table *table)
1134{
1135        return table->flags & NFT_TABLE_F_OWNER;
1136}
1137
1138static inline bool nft_base_chain_netdev(int family, u32 hooknum)
1139{
1140        return family == NFPROTO_NETDEV ||
1141               (family == NFPROTO_INET && hooknum == NF_INET_INGRESS);
1142}
1143
1144void nft_register_chain_type(const struct nft_chain_type *);
1145void nft_unregister_chain_type(const struct nft_chain_type *);
1146
1147int nft_register_expr(struct nft_expr_type *);
1148void nft_unregister_expr(struct nft_expr_type *);
1149
1150int nft_verdict_dump(struct sk_buff *skb, int type,
1151                     const struct nft_verdict *v);
1152
1153/**
1154 *      struct nft_object_hash_key - key to lookup nft_object
1155 *
1156 *      @name: name of the stateful object to look up
1157 *      @table: table the object belongs to
1158 */
1159struct nft_object_hash_key {
1160        const char                      *name;
1161        const struct nft_table          *table;
1162};
1163
1164/**
1165 *      struct nft_object - nf_tables stateful object
1166 *
1167 *      @list: table stateful object list node
1168 *      @key:  keys that identify this object
1169 *      @rhlhead: nft_objname_ht node
1170 *      @genmask: generation mask
1171 *      @use: number of references to this stateful object
1172 *      @handle: unique object handle
1173 *      @ops: object operations
1174 *      @data: object data, layout depends on type
1175 */
1176struct nft_object {
1177        struct list_head                list;
1178        struct rhlist_head              rhlhead;
1179        struct nft_object_hash_key      key;
1180        u32                             genmask:2,
1181                                        use:30;
1182        u64                             handle;
1183        u16                             udlen;
1184        u8                              *udata;
1185        /* runtime data below here */
1186        const struct nft_object_ops     *ops ____cacheline_aligned;
1187        unsigned char                   data[]
1188                __attribute__((aligned(__alignof__(u64))));
1189};
1190
1191static inline void *nft_obj_data(const struct nft_object *obj)
1192{
1193        return (void *)obj->data;
1194}
1195
1196#define nft_expr_obj(expr)      *((struct nft_object **)nft_expr_priv(expr))
1197
1198struct nft_object *nft_obj_lookup(const struct net *net,
1199                                  const struct nft_table *table,
1200                                  const struct nlattr *nla, u32 objtype,
1201                                  u8 genmask);
1202
1203void nft_obj_notify(struct net *net, const struct nft_table *table,
1204                    struct nft_object *obj, u32 portid, u32 seq,
1205                    int event, int family, int report, gfp_t gfp);
1206
1207/**
1208 *      struct nft_object_type - stateful object type
1209 *
1210 *      @select_ops: function to select nft_object_ops
1211 *      @ops: default ops, used when no select_ops functions is present
1212 *      @list: list node in list of object types
1213 *      @type: stateful object numeric type
1214 *      @owner: module owner
1215 *      @maxattr: maximum netlink attribute
1216 *      @policy: netlink attribute policy
1217 */
1218struct nft_object_type {
1219        const struct nft_object_ops     *(*select_ops)(const struct nft_ctx *,
1220                                                       const struct nlattr * const tb[]);
1221        const struct nft_object_ops     *ops;
1222        struct list_head                list;
1223        u32                             type;
1224        unsigned int                    maxattr;
1225        struct module                   *owner;
1226        const struct nla_policy         *policy;
1227};
1228
1229/**
1230 *      struct nft_object_ops - stateful object operations
1231 *
1232 *      @eval: stateful object evaluation function
1233 *      @size: stateful object size
1234 *      @init: initialize object from netlink attributes
1235 *      @destroy: release existing stateful object
1236 *      @dump: netlink dump stateful object
1237 *      @update: update stateful object
1238 */
1239struct nft_object_ops {
1240        void                            (*eval)(struct nft_object *obj,
1241                                                struct nft_regs *regs,
1242                                                const struct nft_pktinfo *pkt);
1243        unsigned int                    size;
1244        int                             (*init)(const struct nft_ctx *ctx,
1245                                                const struct nlattr *const tb[],
1246                                                struct nft_object *obj);
1247        void                            (*destroy)(const struct nft_ctx *ctx,
1248                                                   struct nft_object *obj);
1249        int                             (*dump)(struct sk_buff *skb,
1250                                                struct nft_object *obj,
1251                                                bool reset);
1252        void                            (*update)(struct nft_object *obj,
1253                                                  struct nft_object *newobj);
1254        const struct nft_object_type    *type;
1255};
1256
1257int nft_register_obj(struct nft_object_type *obj_type);
1258void nft_unregister_obj(struct nft_object_type *obj_type);
1259
1260#define NFT_NETDEVICE_MAX       256
1261
1262/**
1263 *      struct nft_flowtable - nf_tables flow table
1264 *
1265 *      @list: flow table list node in table list
1266 *      @table: the table the flow table is contained in
1267 *      @name: name of this flow table
1268 *      @hooknum: hook number
1269 *      @ops_len: number of hooks in array
1270 *      @genmask: generation mask
1271 *      @use: number of references to this flow table
1272 *      @handle: unique object handle
1273 *      @dev_name: array of device names
1274 *      @data: rhashtable and garbage collector
1275 *      @ops: array of hooks
1276 */
1277struct nft_flowtable {
1278        struct list_head                list;
1279        struct nft_table                *table;
1280        char                            *name;
1281        int                             hooknum;
1282        int                             ops_len;
1283        u32                             genmask:2,
1284                                        use:30;
1285        u64                             handle;
1286        /* runtime data below here */
1287        struct list_head                hook_list ____cacheline_aligned;
1288        struct nf_flowtable             data;
1289};
1290
1291struct nft_flowtable *nft_flowtable_lookup(const struct nft_table *table,
1292                                           const struct nlattr *nla,
1293                                           u8 genmask);
1294
1295void nf_tables_deactivate_flowtable(const struct nft_ctx *ctx,
1296                                    struct nft_flowtable *flowtable,
1297                                    enum nft_trans_phase phase);
1298
1299void nft_register_flowtable_type(struct nf_flowtable_type *type);
1300void nft_unregister_flowtable_type(struct nf_flowtable_type *type);
1301
1302/**
1303 *      struct nft_traceinfo - nft tracing information and state
1304 *
1305 *      @pkt: pktinfo currently processed
1306 *      @basechain: base chain currently processed
1307 *      @chain: chain currently processed
1308 *      @rule:  rule that was evaluated
1309 *      @verdict: verdict given by rule
1310 *      @type: event type (enum nft_trace_types)
1311 *      @packet_dumped: packet headers sent in a previous traceinfo message
1312 *      @trace: other struct members are initialised
1313 */
1314struct nft_traceinfo {
1315        const struct nft_pktinfo        *pkt;
1316        const struct nft_base_chain     *basechain;
1317        const struct nft_chain          *chain;
1318        const struct nft_rule           *rule;
1319        const struct nft_verdict        *verdict;
1320        enum nft_trace_types            type;
1321        bool                            packet_dumped;
1322        bool                            trace;
1323};
1324
1325void nft_trace_init(struct nft_traceinfo *info, const struct nft_pktinfo *pkt,
1326                    const struct nft_verdict *verdict,
1327                    const struct nft_chain *basechain);
1328
1329void nft_trace_notify(struct nft_traceinfo *info);
1330
1331#define MODULE_ALIAS_NFT_CHAIN(family, name) \
1332        MODULE_ALIAS("nft-chain-" __stringify(family) "-" name)
1333
1334#define MODULE_ALIAS_NFT_AF_EXPR(family, name) \
1335        MODULE_ALIAS("nft-expr-" __stringify(family) "-" name)
1336
1337#define MODULE_ALIAS_NFT_EXPR(name) \
1338        MODULE_ALIAS("nft-expr-" name)
1339
1340#define MODULE_ALIAS_NFT_OBJ(type) \
1341        MODULE_ALIAS("nft-obj-" __stringify(type))
1342
1343#if IS_ENABLED(CONFIG_NF_TABLES)
1344
1345/*
1346 * The gencursor defines two generations, the currently active and the
1347 * next one. Objects contain a bitmask of 2 bits specifying the generations
1348 * they're active in. A set bit means they're inactive in the generation
1349 * represented by that bit.
1350 *
1351 * New objects start out as inactive in the current and active in the
1352 * next generation. When committing the ruleset the bitmask is cleared,
1353 * meaning they're active in all generations. When removing an object,
1354 * it is set inactive in the next generation. After committing the ruleset,
1355 * the objects are removed.
1356 */
1357static inline unsigned int nft_gencursor_next(const struct net *net)
1358{
1359        return net->nft.gencursor + 1 == 1 ? 1 : 0;
1360}
1361
1362static inline u8 nft_genmask_next(const struct net *net)
1363{
1364        return 1 << nft_gencursor_next(net);
1365}
1366
1367static inline u8 nft_genmask_cur(const struct net *net)
1368{
1369        /* Use READ_ONCE() to prevent refetching the value for atomicity */
1370        return 1 << READ_ONCE(net->nft.gencursor);
1371}
1372
1373#define NFT_GENMASK_ANY         ((1 << 0) | (1 << 1))
1374
1375/*
1376 * Generic transaction helpers
1377 */
1378
1379/* Check if this object is currently active. */
1380#define nft_is_active(__net, __obj)                             \
1381        (((__obj)->genmask & nft_genmask_cur(__net)) == 0)
1382
1383/* Check if this object is active in the next generation. */
1384#define nft_is_active_next(__net, __obj)                        \
1385        (((__obj)->genmask & nft_genmask_next(__net)) == 0)
1386
1387/* This object becomes active in the next generation. */
1388#define nft_activate_next(__net, __obj)                         \
1389        (__obj)->genmask = nft_genmask_cur(__net)
1390
1391/* This object becomes inactive in the next generation. */
1392#define nft_deactivate_next(__net, __obj)                       \
1393        (__obj)->genmask = nft_genmask_next(__net)
1394
1395/* After committing the ruleset, clear the stale generation bit. */
1396#define nft_clear(__net, __obj)                                 \
1397        (__obj)->genmask &= ~nft_genmask_next(__net)
1398#define nft_active_genmask(__obj, __genmask)                    \
1399        !((__obj)->genmask & __genmask)
1400
1401/*
1402 * Set element transaction helpers
1403 */
1404
1405static inline bool nft_set_elem_active(const struct nft_set_ext *ext,
1406                                       u8 genmask)
1407{
1408        return !(ext->genmask & genmask);
1409}
1410
1411static inline void nft_set_elem_change_active(const struct net *net,
1412                                              const struct nft_set *set,
1413                                              struct nft_set_ext *ext)
1414{
1415        ext->genmask ^= nft_genmask_next(net);
1416}
1417
1418#endif /* IS_ENABLED(CONFIG_NF_TABLES) */
1419
1420/*
1421 * We use a free bit in the genmask field to indicate the element
1422 * is busy, meaning it is currently being processed either by
1423 * the netlink API or GC.
1424 *
1425 * Even though the genmask is only a single byte wide, this works
1426 * because the extension structure if fully constant once initialized,
1427 * so there are no non-atomic write accesses unless it is already
1428 * marked busy.
1429 */
1430#define NFT_SET_ELEM_BUSY_MASK  (1 << 2)
1431
1432#if defined(__LITTLE_ENDIAN_BITFIELD)
1433#define NFT_SET_ELEM_BUSY_BIT   2
1434#elif defined(__BIG_ENDIAN_BITFIELD)
1435#define NFT_SET_ELEM_BUSY_BIT   (BITS_PER_LONG - BITS_PER_BYTE + 2)
1436#else
1437#error
1438#endif
1439
1440static inline int nft_set_elem_mark_busy(struct nft_set_ext *ext)
1441{
1442        unsigned long *word = (unsigned long *)ext;
1443
1444        BUILD_BUG_ON(offsetof(struct nft_set_ext, genmask) != 0);
1445        return test_and_set_bit(NFT_SET_ELEM_BUSY_BIT, word);
1446}
1447
1448static inline void nft_set_elem_clear_busy(struct nft_set_ext *ext)
1449{
1450        unsigned long *word = (unsigned long *)ext;
1451
1452        clear_bit(NFT_SET_ELEM_BUSY_BIT, word);
1453}
1454
1455/**
1456 *      struct nft_trans - nf_tables object update in transaction
1457 *
1458 *      @list: used internally
1459 *      @msg_type: message type
1460 *      @put_net: ctx->net needs to be put
1461 *      @ctx: transaction context
1462 *      @data: internal information related to the transaction
1463 */
1464struct nft_trans {
1465        struct list_head                list;
1466        int                             msg_type;
1467        bool                            put_net;
1468        struct nft_ctx                  ctx;
1469        char                            data[];
1470};
1471
1472struct nft_trans_rule {
1473        struct nft_rule                 *rule;
1474        struct nft_flow_rule            *flow;
1475        u32                             rule_id;
1476};
1477
1478#define nft_trans_rule(trans)   \
1479        (((struct nft_trans_rule *)trans->data)->rule)
1480#define nft_trans_flow_rule(trans)      \
1481        (((struct nft_trans_rule *)trans->data)->flow)
1482#define nft_trans_rule_id(trans)        \
1483        (((struct nft_trans_rule *)trans->data)->rule_id)
1484
1485struct nft_trans_set {
1486        struct nft_set                  *set;
1487        u32                             set_id;
1488        bool                            bound;
1489};
1490
1491#define nft_trans_set(trans)    \
1492        (((struct nft_trans_set *)trans->data)->set)
1493#define nft_trans_set_id(trans) \
1494        (((struct nft_trans_set *)trans->data)->set_id)
1495#define nft_trans_set_bound(trans)      \
1496        (((struct nft_trans_set *)trans->data)->bound)
1497
1498struct nft_trans_chain {
1499        bool                            update;
1500        char                            *name;
1501        struct nft_stats __percpu       *stats;
1502        u8                              policy;
1503        u32                             chain_id;
1504};
1505
1506#define nft_trans_chain_update(trans)   \
1507        (((struct nft_trans_chain *)trans->data)->update)
1508#define nft_trans_chain_name(trans)     \
1509        (((struct nft_trans_chain *)trans->data)->name)
1510#define nft_trans_chain_stats(trans)    \
1511        (((struct nft_trans_chain *)trans->data)->stats)
1512#define nft_trans_chain_policy(trans)   \
1513        (((struct nft_trans_chain *)trans->data)->policy)
1514#define nft_trans_chain_id(trans)       \
1515        (((struct nft_trans_chain *)trans->data)->chain_id)
1516
1517struct nft_trans_table {
1518        bool                            update;
1519};
1520
1521#define nft_trans_table_update(trans)   \
1522        (((struct nft_trans_table *)trans->data)->update)
1523
1524struct nft_trans_elem {
1525        struct nft_set                  *set;
1526        struct nft_set_elem             elem;
1527        bool                            bound;
1528};
1529
1530#define nft_trans_elem_set(trans)       \
1531        (((struct nft_trans_elem *)trans->data)->set)
1532#define nft_trans_elem(trans)   \
1533        (((struct nft_trans_elem *)trans->data)->elem)
1534#define nft_trans_elem_set_bound(trans) \
1535        (((struct nft_trans_elem *)trans->data)->bound)
1536
1537struct nft_trans_obj {
1538        struct nft_object               *obj;
1539        struct nft_object               *newobj;
1540        bool                            update;
1541};
1542
1543#define nft_trans_obj(trans)    \
1544        (((struct nft_trans_obj *)trans->data)->obj)
1545#define nft_trans_obj_newobj(trans) \
1546        (((struct nft_trans_obj *)trans->data)->newobj)
1547#define nft_trans_obj_update(trans)     \
1548        (((struct nft_trans_obj *)trans->data)->update)
1549
1550struct nft_trans_flowtable {
1551        struct nft_flowtable            *flowtable;
1552        bool                            update;
1553        struct list_head                hook_list;
1554        u32                             flags;
1555};
1556
1557#define nft_trans_flowtable(trans)      \
1558        (((struct nft_trans_flowtable *)trans->data)->flowtable)
1559#define nft_trans_flowtable_update(trans)       \
1560        (((struct nft_trans_flowtable *)trans->data)->update)
1561#define nft_trans_flowtable_hooks(trans)        \
1562        (((struct nft_trans_flowtable *)trans->data)->hook_list)
1563#define nft_trans_flowtable_flags(trans)        \
1564        (((struct nft_trans_flowtable *)trans->data)->flags)
1565
1566int __init nft_chain_filter_init(void);
1567void nft_chain_filter_fini(void);
1568
1569void __init nft_chain_route_init(void);
1570void nft_chain_route_fini(void);
1571
1572void nf_tables_trans_destroy_flush_work(void);
1573
1574int nf_msecs_to_jiffies64(const struct nlattr *nla, u64 *result);
1575__be64 nf_jiffies64_to_msecs(u64 input);
1576
1577#ifdef CONFIG_MODULES
1578__printf(2, 3) int nft_request_module(struct net *net, const char *fmt, ...);
1579#else
1580static inline int nft_request_module(struct net *net, const char *fmt, ...) { return -ENOENT; }
1581#endif
1582
1583struct nftables_pernet {
1584        struct list_head        tables;
1585        struct list_head        commit_list;
1586        struct list_head        module_list;
1587        struct list_head        notify_list;
1588        struct mutex            commit_mutex;
1589        unsigned int            base_seq;
1590        u8                      validate_state;
1591};
1592
1593extern unsigned int nf_tables_net_id;
1594
1595static inline struct nftables_pernet *nft_pernet(const struct net *net)
1596{
1597        return net_generic(net, nf_tables_net_id);
1598}
1599
1600#endif /* _NET_NF_TABLES_H */
1601