include/linux/netfilter/ipset/ip_set.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
   3  *                         Patrick Schaaf <bof@bof.de>
   4  *                         Martin Josefsson <gandalf@wlug.westbo.se>
   5  * Copyright (C) 2003-2013 Jozsef Kadlecsik <kadlec@netfilter.org>
   6  */
   7 #ifndef _IP_SET_H
   8 #define _IP_SET_H
   9
  10 #include <linux/ip.h>
  11 #include <linux/ipv6.h>
  12 #include <linux/netlink.h>
  13 #include <linux/netfilter.h>
  14 #include <linux/netfilter/x_tables.h>
  15 #include <linux/stringify.h>
  16 #include <linux/vmalloc.h>
  17 #include <net/netlink.h>
  18 #include <uapi/linux/netfilter/ipset/ip_set.h>
  19
  20 #define _IP_SET_MODULE_DESC(a, b, c)            \
  21         MODULE_DESCRIPTION(a " type of IP sets, revisions " b "-" c)
  22 #define IP_SET_MODULE_DESC(a, b, c)             \
  23         _IP_SET_MODULE_DESC(a, __stringify(b), __stringify(c))
  24
  25 /* Set features */
  26 enum ip_set_feature {
  27         IPSET_TYPE_IP_FLAG = 0,
  28         IPSET_TYPE_IP = (1 << IPSET_TYPE_IP_FLAG),
  29         IPSET_TYPE_PORT_FLAG = 1,
  30         IPSET_TYPE_PORT = (1 << IPSET_TYPE_PORT_FLAG),
  31         IPSET_TYPE_MAC_FLAG = 2,
  32         IPSET_TYPE_MAC = (1 << IPSET_TYPE_MAC_FLAG),
  33         IPSET_TYPE_IP2_FLAG = 3,
  34         IPSET_TYPE_IP2 = (1 << IPSET_TYPE_IP2_FLAG),
  35         IPSET_TYPE_NAME_FLAG = 4,
  36         IPSET_TYPE_NAME = (1 << IPSET_TYPE_NAME_FLAG),
  37         IPSET_TYPE_IFACE_FLAG = 5,
  38         IPSET_TYPE_IFACE = (1 << IPSET_TYPE_IFACE_FLAG),
  39         IPSET_TYPE_MARK_FLAG = 6,
  40         IPSET_TYPE_MARK = (1 << IPSET_TYPE_MARK_FLAG),
  41         IPSET_TYPE_NOMATCH_FLAG = 7,
  42         IPSET_TYPE_NOMATCH = (1 << IPSET_TYPE_NOMATCH_FLAG),
  43         /* Strictly speaking not a feature, but a flag for dumping:
  44          * this settype must be dumped last */
  45         IPSET_DUMP_LAST_FLAG = 8,
  46         IPSET_DUMP_LAST = (1 << IPSET_DUMP_LAST_FLAG),
  47 };
  48
  49 /* Set extensions */
  50 enum ip_set_extension {
  51         IPSET_EXT_BIT_TIMEOUT = 0,
  52         IPSET_EXT_TIMEOUT = (1 << IPSET_EXT_BIT_TIMEOUT),
  53         IPSET_EXT_BIT_COUNTER = 1,
  54         IPSET_EXT_COUNTER = (1 << IPSET_EXT_BIT_COUNTER),
  55         IPSET_EXT_BIT_COMMENT = 2,
  56         IPSET_EXT_COMMENT = (1 << IPSET_EXT_BIT_COMMENT),
  57         IPSET_EXT_BIT_SKBINFO = 3,
  58         IPSET_EXT_SKBINFO = (1 << IPSET_EXT_BIT_SKBINFO),
  59         /* Mark set with an extension which needs to call destroy */
  60         IPSET_EXT_BIT_DESTROY = 7,
  61         IPSET_EXT_DESTROY = (1 << IPSET_EXT_BIT_DESTROY),
  62 };
  63
  64 #define SET_WITH_TIMEOUT(s)     ((s)->extensions & IPSET_EXT_TIMEOUT)
  65 #define SET_WITH_COUNTER(s)     ((s)->extensions & IPSET_EXT_COUNTER)
  66 #define SET_WITH_COMMENT(s)     ((s)->extensions & IPSET_EXT_COMMENT)
  67 #define SET_WITH_SKBINFO(s)     ((s)->extensions & IPSET_EXT_SKBINFO)
  68 #define SET_WITH_FORCEADD(s)    ((s)->flags & IPSET_CREATE_FLAG_FORCEADD)
  69
  70 /* Extension id, in size order */
  71 enum ip_set_ext_id {
  72         IPSET_EXT_ID_COUNTER = 0,
  73         IPSET_EXT_ID_TIMEOUT,
  74         IPSET_EXT_ID_SKBINFO,
  75         IPSET_EXT_ID_COMMENT,
  76         IPSET_EXT_ID_MAX,
  77 };
  78
  79 struct ip_set;
  80
  81 /* Extension type */
  82 struct ip_set_ext_type {
  83         /* Destroy extension private data (can be NULL) */
  84         void (*destroy)(struct ip_set *set, void *ext);
  85         enum ip_set_extension type;
  86         enum ipset_cadt_flags flag;
  87         /* Size and minimal alignment */
  88         u8 len;
  89         u8 align;
  90 };
  91
  92 extern const struct ip_set_ext_type ip_set_extensions[];
  93
  94 struct ip_set_counter {
  95         atomic64_t bytes;
  96         atomic64_t packets;
  97 };
  98
  99 struct ip_set_comment_rcu {
 100         struct rcu_head rcu;
 101         char str[0];
 102 };
 103
 104 struct ip_set_comment {
 105         struct ip_set_comment_rcu __rcu *c;
 106 };
 107
 108 struct ip_set_skbinfo {
 109         u32 skbmark;
 110         u32 skbmarkmask;
 111         u32 skbprio;
 112         u16 skbqueue;
 113         u16 __pad;
 114 };
 115
 116 struct ip_set_ext {
 117         struct ip_set_skbinfo skbinfo;
 118         u64 packets;
 119         u64 bytes;
 120         char *comment;
 121         u32 timeout;
 122         u8 packets_op;
 123         u8 bytes_op;
 124         bool target;
 125 };
 126
 127 struct ip_set;
 128
 129 #define ext_timeout(e, s)       \
 130 ((unsigned long *)(((void *)(e)) + (s)->offset[IPSET_EXT_ID_TIMEOUT]))
 131 #define ext_counter(e, s)       \
 132 ((struct ip_set_counter *)(((void *)(e)) + (s)->offset[IPSET_EXT_ID_COUNTER]))
 133 #define ext_comment(e, s)       \
 134 ((struct ip_set_comment *)(((void *)(e)) + (s)->offset[IPSET_EXT_ID_COMMENT]))
 135 #define ext_skbinfo(e, s)       \
 136 ((struct ip_set_skbinfo *)(((void *)(e)) + (s)->offset[IPSET_EXT_ID_SKBINFO]))
 137
 138 typedef int (*ipset_adtfn)(struct ip_set *set, void *value,
 139                            const struct ip_set_ext *ext,
 140                            struct ip_set_ext *mext, u32 cmdflags);
 141
 142 /* Kernel API function options */
 143 struct ip_set_adt_opt {
 144         u8 family;              /* Actual protocol family */
 145         u8 dim;                 /* Dimension of match/target */
 146         u8 flags;               /* Direction and negation flags */
 147         u32 cmdflags;           /* Command-like flags */
 148         struct ip_set_ext ext;  /* Extensions */
 149 };
 150
 151 /* Set type, variant-specific part */
 152 struct ip_set_type_variant {
 153         /* Kernelspace: test/add/del entries
 154          *              returns negative error code,
 155          *                      zero for no match/success to add/delete
 156          *                      positive for matching element */
 157         int (*kadt)(struct ip_set *set, const struct sk_buff *skb,
 158                     const struct xt_action_param *par,
 159                     enum ipset_adt adt, struct ip_set_adt_opt *opt);
 160
 161         /* Userspace: test/add/del entries
 162          *              returns negative error code,
 163          *                      zero for no match/success to add/delete
 164          *                      positive for matching element */
 165         int (*uadt)(struct ip_set *set, struct nlattr *tb[],
 166                     enum ipset_adt adt, u32 *lineno, u32 flags, bool retried);
 167
 168         /* Low level add/del/test functions */
 169         ipset_adtfn adt[IPSET_ADT_MAX];
 170
 171         /* When adding entries and set is full, try to resize the set */
 172         int (*resize)(struct ip_set *set, bool retried);
 173         /* Destroy the set */
 174         void (*destroy)(struct ip_set *set);
 175         /* Flush the elements */
 176         void (*flush)(struct ip_set *set);
 177         /* Expire entries before listing */
 178         void (*expire)(struct ip_set *set);
 179         /* List set header data */
 180         int (*head)(struct ip_set *set, struct sk_buff *skb);
 181         /* List elements */
 182         int (*list)(const struct ip_set *set, struct sk_buff *skb,
 183                     struct netlink_callback *cb);
 184         /* Keep listing private when resizing runs parallel */
 185         void (*uref)(struct ip_set *set, struct netlink_callback *cb,
 186                      bool start);
 187
 188         /* Return true if "b" set is the same as "a"
 189          * according to the create set parameters */
 190         bool (*same_set)(const struct ip_set *a, const struct ip_set *b);
 191         /* Region-locking is used */
 192         bool region_lock;
 193 };
 194
 195 struct ip_set_region {
 196         spinlock_t lock;        /* Region lock */
 197         size_t ext_size;        /* Size of the dynamic extensions */
 198         u32 elements;           /* Number of elements vs timeout */
 199 };
 200
 201 /* The core set type structure */
 202 struct ip_set_type {
 203         struct list_head list;
 204
 205         /* Typename */
 206         char name[IPSET_MAXNAMELEN];
 207         /* Protocol version */
 208         u8 protocol;
 209         /* Set type dimension */
 210         u8 dimension;
 211         /*
 212          * Supported family: may be NFPROTO_UNSPEC for both
 213          * NFPROTO_IPV4/NFPROTO_IPV6.
 214          */
 215         u8 family;
 216         /* Type revisions */
 217         u8 revision_min, revision_max;
 218         /* Set features to control swapping */
 219         u16 features;
 220
 221         /* Create set */
 222         int (*create)(struct net *net, struct ip_set *set,
 223                       struct nlattr *tb[], u32 flags);
 224
 225         /* Attribute policies */
 226         const struct nla_policy create_policy[IPSET_ATTR_CREATE_MAX + 1];
 227         const struct nla_policy adt_policy[IPSET_ATTR_ADT_MAX + 1];
 228
 229         /* Set this to THIS_MODULE if you are a module, otherwise NULL */
 230         struct module *me;
 231 };
 232
 233 /* register and unregister set type */
 234 extern int ip_set_type_register(struct ip_set_type *set_type);
 235 extern void ip_set_type_unregister(struct ip_set_type *set_type);
 236
 237 /* A generic IP set */
 238 struct ip_set {
 239         /* The name of the set */
 240         char name[IPSET_MAXNAMELEN];
 241         /* Lock protecting the set data */
 242         spinlock_t lock;
 243         /* References to the set */
 244         u32 ref;
 245         /* References to the set for netlink events like dump,
 246          * ref can be swapped out by ip_set_swap
 247          */
 248         u32 ref_netlink;
 249         /* The core set type */
 250         struct ip_set_type *type;
 251         /* The type variant doing the real job */
 252         const struct ip_set_type_variant *variant;
 253         /* The actual INET family of the set */
 254         u8 family;
 255         /* The type revision */
 256         u8 revision;
 257         /* Extensions */
 258         u8 extensions;
 259         /* Create flags */
 260         u8 flags;
 261         /* Default timeout value, if enabled */
 262         u32 timeout;
 263         /* Number of elements (vs timeout) */
 264         u32 elements;
 265         /* Size of the dynamic extensions (vs timeout) */
 266         size_t ext_size;
 267         /* Element data size */
 268         size_t dsize;
 269         /* Offsets to extensions in elements */
 270         size_t offset[IPSET_EXT_ID_MAX];
 271         /* The type specific data */
 272         void *data;
 273 };
 274
 275 static inline void
 276 ip_set_ext_destroy(struct ip_set *set, void *data)
 277 {
 278         /* Check that the extension is enabled for the set and
 279          * call it's destroy function for its extension part in data.
 280          */
 281         if (SET_WITH_COMMENT(set)) {
 282                 struct ip_set_comment *c = ext_comment(data, set);
 283
 284                 ip_set_extensions[IPSET_EXT_ID_COMMENT].destroy(set, c);
 285         }
 286 }
 287
 288 int ip_set_put_flags(struct sk_buff *skb, struct ip_set *set);
 289
 290 /* Netlink CB args */
 291 enum {
 292         IPSET_CB_NET = 0,       /* net namespace */
 293         IPSET_CB_PROTO,         /* ipset protocol */
 294         IPSET_CB_DUMP,          /* dump single set/all sets */
 295         IPSET_CB_INDEX,         /* set index */
 296         IPSET_CB_PRIVATE,       /* set private data */
 297         IPSET_CB_ARG0,          /* type specific */
 298 };
 299
 300 /* register and unregister set references */
 301 extern ip_set_id_t ip_set_get_byname(struct net *net,
 302                                      const char *name, struct ip_set **set);
 303 extern void ip_set_put_byindex(struct net *net, ip_set_id_t index);
 304 extern void ip_set_name_byindex(struct net *net, ip_set_id_t index, char *name);
 305 extern ip_set_id_t ip_set_nfnl_get_byindex(struct net *net, ip_set_id_t index);
 306 extern void ip_set_nfnl_put(struct net *net, ip_set_id_t index);
 307
 308 /* API for iptables set match, and SET target */
 309
 310 extern int ip_set_add(ip_set_id_t id, const struct sk_buff *skb,
 311                       const struct xt_action_param *par,
 312                       struct ip_set_adt_opt *opt);
 313 extern int ip_set_del(ip_set_id_t id, const struct sk_buff *skb,
 314                       const struct xt_action_param *par,
 315                       struct ip_set_adt_opt *opt);
 316 extern int ip_set_test(ip_set_id_t id, const struct sk_buff *skb,
 317                        const struct xt_action_param *par,
 318                        struct ip_set_adt_opt *opt);
 319
 320 /* Utility functions */
 321 extern void *ip_set_alloc(size_t size);
 322 extern void ip_set_free(void *members);
 323 extern int ip_set_get_ipaddr4(struct nlattr *nla,  __be32 *ipaddr);
 324 extern int ip_set_get_ipaddr6(struct nlattr *nla, union nf_inet_addr *ipaddr);
 325 extern size_t ip_set_elem_len(struct ip_set *set, struct nlattr *tb[],
 326                               size_t len, size_t align);
 327 extern int ip_set_get_extensions(struct ip_set *set, struct nlattr *tb[],
 328                                  struct ip_set_ext *ext);
 329 extern int ip_set_put_extensions(struct sk_buff *skb, const struct ip_set *set,
 330                                  const void *e, bool active);
 331 extern bool ip_set_match_extensions(struct ip_set *set,
 332                                     const struct ip_set_ext *ext,
 333                                     struct ip_set_ext *mext,
 334                                     u32 flags, void *data);
 335
 336 static inline int
 337 ip_set_get_hostipaddr4(struct nlattr *nla, u32 *ipaddr)
 338 {
 339         __be32 ip;
 340         int ret = ip_set_get_ipaddr4(nla, &ip);
 341
 342         if (ret)
 343                 return ret;
 344         *ipaddr = ntohl(ip);
 345         return 0;
 346 }
 347
 348 /* Ignore IPSET_ERR_EXIST errors if asked to do so? */
 349 static inline bool
 350 ip_set_eexist(int ret, u32 flags)
 351 {
 352         return ret == -IPSET_ERR_EXIST && (flags & IPSET_FLAG_EXIST);
 353 }
 354
 355 /* Match elements marked with nomatch */
 356 static inline bool
 357 ip_set_enomatch(int ret, u32 flags, enum ipset_adt adt, struct ip_set *set)
 358 {
 359         return adt == IPSET_TEST &&
 360                (set->type->features & IPSET_TYPE_NOMATCH) &&
 361                ((flags >> 16) & IPSET_FLAG_NOMATCH) &&
 362                (ret > 0 || ret == -ENOTEMPTY);
 363 }
 364
 365 /* Check the NLA_F_NET_BYTEORDER flag */
 366 static inline bool
 367 ip_set_attr_netorder(struct nlattr *tb[], int type)
 368 {
 369         return tb[type] && (tb[type]->nla_type & NLA_F_NET_BYTEORDER);
 370 }
 371
 372 static inline bool
 373 ip_set_optattr_netorder(struct nlattr *tb[], int type)
 374 {
 375         return !tb[type] || (tb[type]->nla_type & NLA_F_NET_BYTEORDER);
 376 }
 377
 378 /* Useful converters */
 379 static inline u32
 380 ip_set_get_h32(const struct nlattr *attr)
 381 {
 382         return ntohl(nla_get_be32(attr));
 383 }
 384
 385 static inline u16
 386 ip_set_get_h16(const struct nlattr *attr)
 387 {
 388         return ntohs(nla_get_be16(attr));
 389 }
 390
 391 static inline int nla_put_ipaddr4(struct sk_buff *skb, int type, __be32 ipaddr)
 392 {
 393         struct nlattr *__nested = nla_nest_start(skb, type);
 394         int ret;
 395
 396         if (!__nested)
 397                 return -EMSGSIZE;
 398         ret = nla_put_in_addr(skb, IPSET_ATTR_IPADDR_IPV4, ipaddr);
 399         if (!ret)
 400                 nla_nest_end(skb, __nested);
 401         return ret;
 402 }
 403
 404 static inline int nla_put_ipaddr6(struct sk_buff *skb, int type,
 405                                   const struct in6_addr *ipaddrptr)
 406 {
 407         struct nlattr *__nested = nla_nest_start(skb, type);
 408         int ret;
 409
 410         if (!__nested)
 411                 return -EMSGSIZE;
 412         ret = nla_put_in6_addr(skb, IPSET_ATTR_IPADDR_IPV6, ipaddrptr);
 413         if (!ret)
 414                 nla_nest_end(skb, __nested);
 415         return ret;
 416 }
 417
 418 /* Get address from skbuff */
 419 static inline __be32
 420 ip4addr(const struct sk_buff *skb, bool src)
 421 {
 422         return src ? ip_hdr(skb)->saddr : ip_hdr(skb)->daddr;
 423 }
 424
 425 static inline void
 426 ip4addrptr(const struct sk_buff *skb, bool src, __be32 *addr)
 427 {
 428         *addr = src ? ip_hdr(skb)->saddr : ip_hdr(skb)->daddr;
 429 }
 430
 431 static inline void
 432 ip6addrptr(const struct sk_buff *skb, bool src, struct in6_addr *addr)
 433 {
 434         memcpy(addr, src ? &ipv6_hdr(skb)->saddr : &ipv6_hdr(skb)->daddr,
 435                sizeof(*addr));
 436 }
 437
 438 /* How often should the gc be run by default */
 439 #define IPSET_GC_TIME                   (3 * 60)
 440
 441 /* Timeout period depending on the timeout value of the given set */
 442 #define IPSET_GC_PERIOD(timeout) \
 443         ((timeout/3) ? min_t(u32, (timeout)/3, IPSET_GC_TIME) : 1)
 444
 445 /* Entry is set with no timeout value */
 446 #define IPSET_ELEM_PERMANENT    0
 447
 448 /* Set is defined with timeout support: timeout value may be 0 */
 449 #define IPSET_NO_TIMEOUT        UINT_MAX
 450
 451 /* Max timeout value, see msecs_to_jiffies() in jiffies.h */
 452 #define IPSET_MAX_TIMEOUT       (UINT_MAX >> 1)/MSEC_PER_SEC
 453
 454 #define ip_set_adt_opt_timeout(opt, set)        \
 455 ((opt)->ext.timeout != IPSET_NO_TIMEOUT ? (opt)->ext.timeout : (set)->timeout)
 456
 457 static inline unsigned int
 458 ip_set_timeout_uget(struct nlattr *tb)
 459 {
 460         unsigned int timeout = ip_set_get_h32(tb);
 461
 462         /* Normalize to fit into jiffies */
 463         if (timeout > IPSET_MAX_TIMEOUT)
 464                 timeout = IPSET_MAX_TIMEOUT;
 465
 466         return timeout;
 467 }
 468
 469 static inline bool
 470 ip_set_timeout_expired(const unsigned long *t)
 471 {
 472         return *t != IPSET_ELEM_PERMANENT && time_is_before_jiffies(*t);
 473 }
 474
 475 static inline void
 476 ip_set_timeout_set(unsigned long *timeout, u32 value)
 477 {
 478         unsigned long t;
 479
 480         if (!value) {
 481                 *timeout = IPSET_ELEM_PERMANENT;
 482                 return;
 483         }
 484
 485         t = msecs_to_jiffies(value * MSEC_PER_SEC) + jiffies;
 486         if (t == IPSET_ELEM_PERMANENT)
 487                 /* Bingo! :-) */
 488                 t--;
 489         *timeout = t;
 490 }
 491
 492 void ip_set_init_comment(struct ip_set *set, struct ip_set_comment *comment,
 493                          const struct ip_set_ext *ext);
 494
 495 static inline void
 496 ip_set_init_counter(struct ip_set_counter *counter,
 497                     const struct ip_set_ext *ext)
 498 {
 499         if (ext->bytes != ULLONG_MAX)
 500                 atomic64_set(&(counter)->bytes, (long long)(ext->bytes));
 501         if (ext->packets != ULLONG_MAX)
 502                 atomic64_set(&(counter)->packets, (long long)(ext->packets));
 503 }
 504
 505 static inline void
 506 ip_set_init_skbinfo(struct ip_set_skbinfo *skbinfo,
 507                     const struct ip_set_ext *ext)
 508 {
 509         *skbinfo = ext->skbinfo;
 510 }
 511
 512 #define IP_SET_INIT_KEXT(skb, opt, set)                 \
 513         { .bytes = (skb)->len, .packets = 1, .target = true,\
 514           .timeout = ip_set_adt_opt_timeout(opt, set) }
 515
 516 #define IP_SET_INIT_UEXT(set)                           \
 517         { .bytes = ULLONG_MAX, .packets = ULLONG_MAX,   \
 518           .timeout = (set)->timeout }
 519
 520 #define IPSET_CONCAT(a, b)              a##b
 521 #define IPSET_TOKEN(a, b)               IPSET_CONCAT(a, b)
 522
 523 #endif /*_IP_SET_H */