blob: 0136028652bdb8b3c20813b01b2fa8cfb16ba012 [file] [log] [blame]
#ifndef _NET_NF_TABLES_H
#define _NET_NF_TABLES_H
#include <linux/module.h>
#include <linux/list.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/nf_tables.h>
#include <linux/u64_stats_sync.h>
#include <net/netlink.h>
#define NFT_JUMP_STACK_SIZE 16
struct nft_pktinfo {
struct sk_buff *skb;
bool tprot_set;
u8 tprot;
/* for x_tables compatibility */
struct xt_action_param xt;
};
static inline struct net *nft_net(const struct nft_pktinfo *pkt)
{
return pkt->xt.state->net;
}
static inline unsigned int nft_hook(const struct nft_pktinfo *pkt)
{
return pkt->xt.state->hook;
}
static inline u8 nft_pf(const struct nft_pktinfo *pkt)
{
return pkt->xt.state->pf;
}
static inline const struct net_device *nft_in(const struct nft_pktinfo *pkt)
{
return pkt->xt.state->in;
}
static inline const struct net_device *nft_out(const struct nft_pktinfo *pkt)
{
return pkt->xt.state->out;
}
static inline void nft_set_pktinfo(struct nft_pktinfo *pkt,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
pkt->skb = skb;
pkt->xt.state = state;
}
static inline void nft_set_pktinfo_proto_unspec(struct nft_pktinfo *pkt,
struct sk_buff *skb)
{
pkt->tprot_set = false;
pkt->tprot = 0;
pkt->xt.thoff = 0;
pkt->xt.fragoff = 0;
}
static inline void nft_set_pktinfo_unspec(struct nft_pktinfo *pkt,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
nft_set_pktinfo(pkt, skb, state);
nft_set_pktinfo_proto_unspec(pkt, skb);
}
/**
* struct nft_verdict - nf_tables verdict
*
* @code: nf_tables/netfilter verdict code
* @chain: destination chain for NFT_JUMP/NFT_GOTO
*/
struct nft_verdict {
u32 code;
struct nft_chain *chain;
};
struct nft_data {
union {
u32 data[4];
struct nft_verdict verdict;
};
} __attribute__((aligned(__alignof__(u64))));
/**
* struct nft_regs - nf_tables register set
*
* @data: data registers
* @verdict: verdict register
*
* The first four data registers alias to the verdict register.
*/
struct nft_regs {
union {
u32 data[20];
struct nft_verdict verdict;
};
};
/* Store/load an u16 or u8 integer to/from the u32 data register.
*
* Note, when using concatenations, register allocation happens at 32-bit
* level. So for store instruction, pad the rest part with zero to avoid
* garbage values.
*/
static inline void nft_reg_store16(u32 *dreg, u16 val)
{
*dreg = 0;
*(u16 *)dreg = val;
}
static inline void nft_reg_store8(u32 *dreg, u8 val)
{
*dreg = 0;
*(u8 *)dreg = val;
}
static inline u16 nft_reg_load16(u32 *sreg)
{
return *(u16 *)sreg;
}
static inline u8 nft_reg_load8(u32 *sreg)
{
return *(u8 *)sreg;
}
static inline void nft_data_copy(u32 *dst, const struct nft_data *src,
unsigned int len)
{
memcpy(dst, src, len);
}
static inline void nft_data_debug(const struct nft_data *data)
{
pr_debug("data[0]=%x data[1]=%x data[2]=%x data[3]=%x\n",
data->data[0], data->data[1],
data->data[2], data->data[3]);
}
/**
* struct nft_ctx - nf_tables rule/set context
*
* @net: net namespace
* @afi: address family info
* @table: the table the chain is contained in
* @chain: the chain the rule is contained in
* @nla: netlink attributes
* @portid: netlink portID of the original message
* @seq: netlink sequence number
* @report: notify via unicast netlink message
*/
struct nft_ctx {
struct net *net;
struct nft_af_info *afi;
struct nft_table *table;
struct nft_chain *chain;
const struct nlattr * const *nla;
u32 portid;
u32 seq;
bool report;
};
struct nft_data_desc {
enum nft_data_types type;
unsigned int len;
};
int nft_data_init(const struct nft_ctx *ctx,
struct nft_data *data, unsigned int size,
struct nft_data_desc *desc, const struct nlattr *nla);
void nft_data_uninit(const struct nft_data *data, enum nft_data_types type);
int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
enum nft_data_types type, unsigned int len);
static inline enum nft_data_types nft_dreg_to_type(enum nft_registers reg)
{
return reg == NFT_REG_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
}
static inline enum nft_registers nft_type_to_reg(enum nft_data_types type)
{
return type == NFT_DATA_VERDICT ? NFT_REG_VERDICT : NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE;
}
int nft_parse_u32_check(const struct nlattr *attr, int max, u32 *dest);
unsigned int nft_parse_register(const struct nlattr *attr);
int nft_dump_register(struct sk_buff *skb, unsigned int attr, unsigned int reg);
int nft_validate_register_load(enum nft_registers reg, unsigned int len);
int nft_validate_register_store(const struct nft_ctx *ctx,
enum nft_registers reg,
const struct nft_data *data,
enum nft_data_types type, unsigned int len);
/**
* struct nft_userdata - user defined data associated with an object
*
* @len: length of the data
* @data: content
*
* The presence of user data is indicated in an object specific fashion,
* so a length of zero can't occur and the value "len" indicates data
* of length len + 1.
*/
struct nft_userdata {
u8 len;
unsigned char data[0];
};
/**
* struct nft_set_elem - generic representation of set elements
*
* @key: element key
* @priv: element private data and extensions
*/
struct nft_set_elem {
union {
u32 buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
struct nft_data val;
} key;
void *priv;
};
struct nft_set;
struct nft_set_iter {
u8 genmask;
unsigned int count;
unsigned int skip;
int err;
int (*fn)(const struct nft_ctx *ctx,
struct nft_set *set,
const struct nft_set_iter *iter,
struct nft_set_elem *elem);
};
/**
* struct nft_set_desc - description of set elements
*
* @klen: key length
* @dlen: data length
* @size: number of set elements
*/
struct nft_set_desc {
unsigned int klen;
unsigned int dlen;
unsigned int size;
};
/**
* enum nft_set_class - performance class
*
* @NFT_LOOKUP_O_1: constant, O(1)
* @NFT_LOOKUP_O_LOG_N: logarithmic, O(log N)
* @NFT_LOOKUP_O_N: linear, O(N)
*/
enum nft_set_class {
NFT_SET_CLASS_O_1,
NFT_SET_CLASS_O_LOG_N,
NFT_SET_CLASS_O_N,
};
/**
* struct nft_set_estimate - estimation of memory and performance
* characteristics
*
* @size: required memory
* @lookup: lookup performance class
* @space: memory class
*/
struct nft_set_estimate {
unsigned int size;
enum nft_set_class lookup;
enum nft_set_class space;
};
struct nft_set_ext;
struct nft_expr;
/**
* struct nft_set_ops - nf_tables set operations
*
* @lookup: look up an element within the set
* @insert: insert new element into set
* @activate: activate new element in the next generation
* @deactivate: lookup for element and deactivate it in the next generation
* @flush: deactivate element in the next generation
* @remove: remove element from set
* @walk: iterate over all set elemeennts
* @privsize: function to return size of set private data
* @init: initialize private data of new set instance
* @destroy: destroy private data of set instance
* @list: nf_tables_set_ops list node
* @owner: module reference
* @elemsize: element private size
* @features: features supported by the implementation
*/
struct nft_set_ops {
bool (*lookup)(const struct net *net,
const struct nft_set *set,
const u32 *key,
const struct nft_set_ext **ext);
bool (*update)(struct nft_set *set,
const u32 *key,
void *(*new)(struct nft_set *,
const struct nft_expr *,
struct nft_regs *),
const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_set_ext **ext);
int (*insert)(const struct net *net,
const struct nft_set *set,
const struct nft_set_elem *elem,
struct nft_set_ext **ext);
void (*activate)(const struct net *net,
const struct nft_set *set,
const struct nft_set_elem *elem);
void * (*deactivate)(const struct net *net,
const struct nft_set *set,
const struct nft_set_elem *elem);
bool (*flush)(const struct net *net,
const struct nft_set *set,
void *priv);
void (*remove)(const struct net *net,
const struct nft_set *set,
const struct nft_set_elem *elem);
void (*walk)(const struct nft_ctx *ctx,
struct nft_set *set,
struct nft_set_iter *iter);
unsigned int (*privsize)(const struct nlattr * const nla[]);
bool (*estimate)(const struct nft_set_desc *desc,
u32 features,
struct nft_set_estimate *est);
int (*init)(const struct nft_set *set,
const struct nft_set_desc *desc,
const struct nlattr * const nla[]);
void (*destroy)(const struct nft_set *set);
struct list_head list;
struct module *owner;
unsigned int elemsize;
u32 features;
};
int nft_register_set(struct nft_set_ops *ops);
void nft_unregister_set(struct nft_set_ops *ops);
/**
* struct nft_set - nf_tables set instance
*
* @list: table set list node
* @bindings: list of set bindings
* @name: name of the set
* @ktype: key type (numeric type defined by userspace, not used in the kernel)
* @dtype: data type (verdict or numeric type defined by userspace)
* @objtype: object type (see NFT_OBJECT_* definitions)
* @size: maximum set size
* @nelems: number of elements
* @ndeact: number of deactivated elements queued for removal
* @timeout: default timeout value in jiffies
* @gc_int: garbage collection interval in msecs
* @policy: set parameterization (see enum nft_set_policies)
* @udlen: user data length
* @udata: user data
* @ops: set ops
* @flags: set flags
* @genmask: generation mask
* @klen: key length
* @dlen: data length
* @data: private set data
*/
struct nft_set {
struct list_head list;
struct list_head bindings;
char name[NFT_SET_MAXNAMELEN];
u32 ktype;
u32 dtype;
u32 objtype;
u32 size;
atomic_t nelems;
u32 ndeact;
u64 timeout;
u32 gc_int;
u16 policy;
u16 udlen;
unsigned char *udata;
/* runtime data below here */
const struct nft_set_ops *ops ____cacheline_aligned;
u16 flags:14,
genmask:2;
u8 klen;
u8 dlen;
unsigned char data[]
__attribute__((aligned(__alignof__(u64))));
};
static inline void *nft_set_priv(const struct nft_set *set)
{
return (void *)set->data;
}
static inline struct nft_set *nft_set_container_of(const void *priv)
{
return (void *)priv - offsetof(struct nft_set, data);
}
struct nft_set *nf_tables_set_lookup(const struct nft_table *table,
const struct nlattr *nla, u8 genmask);
struct nft_set *nf_tables_set_lookup_byid(const struct net *net,
const struct nlattr *nla, u8 genmask);
static inline unsigned long nft_set_gc_interval(const struct nft_set *set)
{
return set->gc_int ? msecs_to_jiffies(set->gc_int) : HZ;
}
/**
* struct nft_set_binding - nf_tables set binding
*
* @list: set bindings list node
* @chain: chain containing the rule bound to the set
* @flags: set action flags
*
* A set binding contains all information necessary for validation
* of new elements added to a bound set.
*/
struct nft_set_binding {
struct list_head list;
const struct nft_chain *chain;
u32 flags;
};
int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
struct nft_set_binding *binding);
void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set,
struct nft_set_binding *binding);
/**
* enum nft_set_extensions - set extension type IDs
*
* @NFT_SET_EXT_KEY: element key
* @NFT_SET_EXT_DATA: mapping data
* @NFT_SET_EXT_FLAGS: element flags
* @NFT_SET_EXT_TIMEOUT: element timeout
* @NFT_SET_EXT_EXPIRATION: element expiration time
* @NFT_SET_EXT_USERDATA: user data associated with the element
* @NFT_SET_EXT_EXPR: expression assiociated with the element
* @NFT_SET_EXT_OBJREF: stateful object reference associated with element
* @NFT_SET_EXT_NUM: number of extension types
*/
enum nft_set_extensions {
NFT_SET_EXT_KEY,
NFT_SET_EXT_DATA,
NFT_SET_EXT_FLAGS,
NFT_SET_EXT_TIMEOUT,
NFT_SET_EXT_EXPIRATION,
NFT_SET_EXT_USERDATA,
NFT_SET_EXT_EXPR,
NFT_SET_EXT_OBJREF,
NFT_SET_EXT_NUM
};
/**
* struct nft_set_ext_type - set extension type
*
* @len: fixed part length of the extension
* @align: alignment requirements of the extension
*/
struct nft_set_ext_type {
u8 len;
u8 align;
};
extern const struct nft_set_ext_type nft_set_ext_types[];
/**
* struct nft_set_ext_tmpl - set extension template
*
* @len: length of extension area
* @offset: offsets of individual extension types
*/
struct nft_set_ext_tmpl {
u16 len;
u8 offset[NFT_SET_EXT_NUM];
};
/**
* struct nft_set_ext - set extensions
*
* @genmask: generation mask
* @offset: offsets of individual extension types
* @data: beginning of extension data
*/
struct nft_set_ext {
u8 genmask;
u8 offset[NFT_SET_EXT_NUM];
char data[0];
};
static inline void nft_set_ext_prepare(struct nft_set_ext_tmpl *tmpl)
{
memset(tmpl, 0, sizeof(*tmpl));
tmpl->len = sizeof(struct nft_set_ext);
}
static inline void nft_set_ext_add_length(struct nft_set_ext_tmpl *tmpl, u8 id,
unsigned int len)
{
tmpl->len = ALIGN(tmpl->len, nft_set_ext_types[id].align);
BUG_ON(tmpl->len > U8_MAX);
tmpl->offset[id] = tmpl->len;
tmpl->len += nft_set_ext_types[id].len + len;
}
static inline void nft_set_ext_add(struct nft_set_ext_tmpl *tmpl, u8 id)
{
nft_set_ext_add_length(tmpl, id, 0);
}
static inline void nft_set_ext_init(struct nft_set_ext *ext,
const struct nft_set_ext_tmpl *tmpl)
{
memcpy(ext->offset, tmpl->offset, sizeof(ext->offset));
}
static inline bool __nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
{
return !!ext->offset[id];
}
static inline bool nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
{
return ext && __nft_set_ext_exists(ext, id);
}
static inline void *nft_set_ext(const struct nft_set_ext *ext, u8 id)
{
return (void *)ext + ext->offset[id];
}
static inline struct nft_data *nft_set_ext_key(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_KEY);
}
static inline struct nft_data *nft_set_ext_data(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_DATA);
}
static inline u8 *nft_set_ext_flags(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_FLAGS);
}
static inline u64 *nft_set_ext_timeout(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_TIMEOUT);
}
static inline unsigned long *nft_set_ext_expiration(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_EXPIRATION);
}
static inline struct nft_userdata *nft_set_ext_userdata(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_USERDATA);
}
static inline struct nft_expr *nft_set_ext_expr(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_EXPR);
}
static inline bool nft_set_elem_expired(const struct nft_set_ext *ext)
{
return nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION) &&
time_is_before_eq_jiffies(*nft_set_ext_expiration(ext));
}
static inline struct nft_set_ext *nft_set_elem_ext(const struct nft_set *set,
void *elem)
{
return elem + set->ops->elemsize;
}
static inline struct nft_object **nft_set_ext_obj(const struct nft_set_ext *ext)
{
return nft_set_ext(ext, NFT_SET_EXT_OBJREF);
}
void *nft_set_elem_init(const struct nft_set *set,
const struct nft_set_ext_tmpl *tmpl,
const u32 *key, const u32 *data,
u64 timeout, gfp_t gfp);
void nft_set_elem_destroy(const struct nft_set *set, void *elem,
bool destroy_expr);
/**
* struct nft_set_gc_batch_head - nf_tables set garbage collection batch
*
* @rcu: rcu head
* @set: set the elements belong to
* @cnt: count of elements
*/
struct nft_set_gc_batch_head {
struct rcu_head rcu;
const struct nft_set *set;
unsigned int cnt;
};
#define NFT_SET_GC_BATCH_SIZE ((PAGE_SIZE - \
sizeof(struct nft_set_gc_batch_head)) / \
sizeof(void *))
/**
* struct nft_set_gc_batch - nf_tables set garbage collection batch
*
* @head: GC batch head
* @elems: garbage collection elements
*/
struct nft_set_gc_batch {
struct nft_set_gc_batch_head head;
void *elems[NFT_SET_GC_BATCH_SIZE];
};
struct nft_set_gc_batch *nft_set_gc_batch_alloc(const struct nft_set *set,
gfp_t gfp);
void nft_set_gc_batch_release(struct rcu_head *rcu);
static inline void nft_set_gc_batch_complete(struct nft_set_gc_batch *gcb)
{
if (gcb != NULL)
call_rcu(&gcb->head.rcu, nft_set_gc_batch_release);
}
static inline struct nft_set_gc_batch *
nft_set_gc_batch_check(const struct nft_set *set, struct nft_set_gc_batch *gcb,
gfp_t gfp)
{
if (gcb != NULL) {
if (gcb->head.cnt + 1 < ARRAY_SIZE(gcb->elems))
return gcb;
nft_set_gc_batch_complete(gcb);
}
return nft_set_gc_batch_alloc(set, gfp);
}
static inline void nft_set_gc_batch_add(struct nft_set_gc_batch *gcb,
void *elem)
{
gcb->elems[gcb->head.cnt++] = elem;
}
/**
* struct nft_expr_type - nf_tables expression type
*
* @select_ops: function to select nft_expr_ops
* @ops: default ops, used when no select_ops functions is present
* @list: used internally
* @name: Identifier
* @owner: module reference
* @policy: netlink attribute policy
* @maxattr: highest netlink attribute number
* @family: address family for AF-specific types
* @flags: expression type flags
*/
struct nft_expr_type {
const struct nft_expr_ops *(*select_ops)(const struct nft_ctx *,
const struct nlattr * const tb[]);
const struct nft_expr_ops *ops;
struct list_head list;
const char *name;
struct module *owner;
const struct nla_policy *policy;
unsigned int maxattr;
u8 family;
u8 flags;
};
#define NFT_EXPR_STATEFUL 0x1
/**
* struct nft_expr_ops - nf_tables expression operations
*
* @eval: Expression evaluation function
* @size: full expression size, including private data size
* @init: initialization function
* @destroy: destruction function
* @dump: function to dump parameters
* @type: expression type
* @validate: validate expression, called during loop detection
* @data: extra data to attach to this expression operation
*/
struct nft_expr;
struct nft_expr_ops {
void (*eval)(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt);
int (*clone)(struct nft_expr *dst,
const struct nft_expr *src);
unsigned int size;
int (*init)(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[]);
void (*destroy)(const struct nft_ctx *ctx,
const struct nft_expr *expr);
int (*dump)(struct sk_buff *skb,
const struct nft_expr *expr);
int (*validate)(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nft_data **data);
const struct nft_expr_type *type;
void *data;
};
#define NFT_EXPR_MAXATTR 16
#define NFT_EXPR_SIZE(size) (sizeof(struct nft_expr) + \
ALIGN(size, __alignof__(struct nft_expr)))
/**
* struct nft_expr - nf_tables expression
*
* @ops: expression ops
* @data: expression private data
*/
struct nft_expr {
const struct nft_expr_ops *ops;
unsigned char data[];
};
static inline void *nft_expr_priv(const struct nft_expr *expr)
{
return (void *)expr->data;
}
struct nft_expr *nft_expr_init(const struct nft_ctx *ctx,
const struct nlattr *nla);
void nft_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr);
int nft_expr_dump(struct sk_buff *skb, unsigned int attr,
const struct nft_expr *expr);
static inline int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src)
{
int err;
if (src->ops->clone) {
dst->ops = src->ops;
err = src->ops->clone(dst, src);
if (err < 0)
return err;
} else {
memcpy(dst, src, src->ops->size);
}
__module_get(src->ops->type->owner);
return 0;
}
/**
* struct nft_rule - nf_tables rule
*
* @list: used internally
* @handle: rule handle
* @genmask: generation mask
* @dlen: length of expression data
* @udata: user data is appended to the rule
* @data: expression data
*/
struct nft_rule {
struct list_head list;
u64 handle:42,
genmask:2,
dlen:12,
udata:1;
unsigned char data[]
__attribute__((aligned(__alignof__(struct nft_expr))));
};
static inline struct nft_expr *nft_expr_first(const struct nft_rule *rule)
{
return (struct nft_expr *)&rule->data[0];
}
static inline struct nft_expr *nft_expr_next(const struct nft_expr *expr)
{
return ((void *)expr) + expr->ops->size;
}
static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule)
{
return (struct nft_expr *)&rule->data[rule->dlen];
}
static inline struct nft_userdata *nft_userdata(const struct nft_rule *rule)
{
return (void *)&rule->data[rule->dlen];
}
/*
* The last pointer isn't really necessary, but the compiler isn't able to
* determine that the result of nft_expr_last() is always the same since it
* can't assume that the dlen value wasn't changed within calls in the loop.
*/
#define nft_rule_for_each_expr(expr, last, rule) \
for ((expr) = nft_expr_first(rule), (last) = nft_expr_last(rule); \
(expr) != (last); \
(expr) = nft_expr_next(expr))
enum nft_chain_flags {
NFT_BASE_CHAIN = 0x1,
};
/**
* struct nft_chain - nf_tables chain
*
* @rules: list of rules in the chain
* @list: used internally
* @table: table that this chain belongs to
* @handle: chain handle
* @use: number of jump references to this chain
* @level: length of longest path to this chain
* @flags: bitmask of enum nft_chain_flags
* @name: name of the chain
*/
struct nft_chain {
struct list_head rules;
struct list_head list;
struct nft_table *table;
u64 handle;
u32 use;
u16 level;
u8 flags:6,
genmask:2;
char name[NFT_CHAIN_MAXNAMELEN];
};
enum nft_chain_type {
NFT_CHAIN_T_DEFAULT = 0,
NFT_CHAIN_T_ROUTE,
NFT_CHAIN_T_NAT,
NFT_CHAIN_T_MAX
};
/**
* struct nf_chain_type - nf_tables chain type info
*
* @name: name of the type
* @type: numeric identifier
* @family: address family
* @owner: module owner
* @hook_mask: mask of valid hooks
* @hooks: hookfn overrides
*/
struct nf_chain_type {
const char *name;
enum nft_chain_type type;
int family;
struct module *owner;
unsigned int hook_mask;
nf_hookfn *hooks[NF_MAX_HOOKS];
};
int nft_chain_validate_dependency(const struct nft_chain *chain,
enum nft_chain_type type);
int nft_chain_validate_hooks(const struct nft_chain *chain,
unsigned int hook_flags);
struct nft_stats {
u64 bytes;
u64 pkts;
struct u64_stats_sync syncp;
};
#define NFT_HOOK_OPS_MAX 2
/**
* struct nft_base_chain - nf_tables base chain
*
* @ops: netfilter hook ops
* @type: chain type
* @policy: default policy
* @stats: per-cpu chain stats
* @chain: the chain
* @dev_name: device name that this base chain is attached to (if any)
*/
struct nft_base_chain {
struct nf_hook_ops ops[NFT_HOOK_OPS_MAX];
const struct nf_chain_type *type;
u8 policy;
u8 flags;
struct nft_stats __percpu *stats;
struct nft_chain chain;
char dev_name[IFNAMSIZ];
};
static inline struct nft_base_chain *nft_base_chain(const struct nft_chain *chain)
{
return container_of(chain, struct nft_base_chain, chain);
}
int __nft_release_basechain(struct nft_ctx *ctx);
unsigned int nft_do_chain(struct nft_pktinfo *pkt, void *priv);
/**
* struct nft_table - nf_tables table
*
* @list: used internally
* @chains: chains in the table
* @sets: sets in the table
* @objects: stateful objects in the table
* @hgenerator: handle generator state
* @use: number of chain references to this table
* @flags: table flag (see enum nft_table_flags)
* @genmask: generation mask
* @name: name of the table
*/
struct nft_table {
struct list_head list;
struct list_head chains;
struct list_head sets;
struct list_head objects;
u64 hgenerator;
u32 use;
u16 flags:14,
genmask:2;
char name[NFT_TABLE_MAXNAMELEN];
};
enum nft_af_flags {
NFT_AF_NEEDS_DEV = (1 << 0),
};
/**
* struct nft_af_info - nf_tables address family info
*
* @list: used internally
* @family: address family
* @nhooks: number of hooks in this family
* @owner: module owner
* @tables: used internally
* @flags: family flags
* @nops: number of hook ops in this family
* @hook_ops_init: initialization function for chain hook ops
* @hooks: hookfn overrides for packet validation
*/
struct nft_af_info {
struct list_head list;
int family;
unsigned int nhooks;
struct module *owner;
struct list_head tables;
u32 flags;
unsigned int nops;
void (*hook_ops_init)(struct nf_hook_ops *,
unsigned int);
nf_hookfn *hooks[NF_MAX_HOOKS];
};
int nft_register_afinfo(struct net *, struct nft_af_info *);
void nft_unregister_afinfo(struct net *, struct nft_af_info *);
int nft_register_chain_type(const struct nf_chain_type *);
void nft_unregister_chain_type(const struct nf_chain_type *);
int nft_register_expr(struct nft_expr_type *);
void nft_unregister_expr(struct nft_expr_type *);
int nft_verdict_dump(struct sk_buff *skb, int type,
const struct nft_verdict *v);
/**
* struct nft_object - nf_tables stateful object
*
* @list: table stateful object list node
* @table: table this object belongs to
* @type: pointer to object type
* @data: pointer to object data
* @name: name of this stateful object
* @genmask: generation mask
* @use: number of references to this stateful object
* @data: object data, layout depends on type
*/
struct nft_object {
struct list_head list;
char name[NFT_OBJ_MAXNAMELEN];
struct nft_table *table;
u32 genmask:2,
use:30;
/* runtime data below here */
const struct nft_object_type *type ____cacheline_aligned;
unsigned char data[]
__attribute__((aligned(__alignof__(u64))));
};
static inline void *nft_obj_data(const struct nft_object *obj)
{
return (void *)obj->data;
}
#define nft_expr_obj(expr) *((struct nft_object **)nft_expr_priv(expr))
struct nft_object *nf_tables_obj_lookup(const struct nft_table *table,
const struct nlattr *nla, u32 objtype,
u8 genmask);
void nft_obj_notify(struct net *net, struct nft_table *table,
struct nft_object *obj, u32 portid, u32 seq,
int event, int family, int report, gfp_t gfp);
/**
* struct nft_object_type - stateful object type
*
* @eval: stateful object evaluation function
* @list: list node in list of object types
* @type: stateful object numeric type
* @size: stateful object size
* @owner: module owner
* @maxattr: maximum netlink attribute
* @policy: netlink attribute policy
* @init: initialize object from netlink attributes
* @destroy: release existing stateful object
* @dump: netlink dump stateful object
*/
struct nft_object_type {
void (*eval)(struct nft_object *obj,
struct nft_regs *regs,
const struct nft_pktinfo *pkt);
struct list_head list;
u32 type;
unsigned int size;
unsigned int maxattr;
struct module *owner;
const struct nla_policy *policy;
int (*init)(const struct nlattr * const tb[],
struct nft_object *obj);
void (*destroy)(struct nft_object *obj);
int (*dump)(struct sk_buff *skb,
struct nft_object *obj,
bool reset);
};
int nft_register_obj(struct nft_object_type *obj_type);
void nft_unregister_obj(struct nft_object_type *obj_type);
/**
* struct nft_traceinfo - nft tracing information and state
*
* @pkt: pktinfo currently processed
* @basechain: base chain currently processed
* @chain: chain currently processed
* @rule: rule that was evaluated
* @verdict: verdict given by rule
* @type: event type (enum nft_trace_types)
* @packet_dumped: packet headers sent in a previous traceinfo message
* @trace: other struct members are initialised
*/
struct nft_traceinfo {
const struct nft_pktinfo *pkt;
const struct nft_base_chain *basechain;
const struct nft_chain *chain;
const struct nft_rule *rule;
const struct nft_verdict *verdict;
enum nft_trace_types type;
bool packet_dumped;
bool trace;
};
void nft_trace_init(struct nft_traceinfo *info, const struct nft_pktinfo *pkt,
const struct nft_verdict *verdict,
const struct nft_chain *basechain);
void nft_trace_notify(struct nft_traceinfo *info);
#define nft_dereference(p) \
nfnl_dereference(p, NFNL_SUBSYS_NFTABLES)
#define MODULE_ALIAS_NFT_FAMILY(family) \
MODULE_ALIAS("nft-afinfo-" __stringify(family))
#define MODULE_ALIAS_NFT_CHAIN(family, name) \
MODULE_ALIAS("nft-chain-" __stringify(family) "-" name)
#define MODULE_ALIAS_NFT_AF_EXPR(family, name) \
MODULE_ALIAS("nft-expr-" __stringify(family) "-" name)
#define MODULE_ALIAS_NFT_EXPR(name) \
MODULE_ALIAS("nft-expr-" name)
#define MODULE_ALIAS_NFT_SET() \
MODULE_ALIAS("nft-set")
#define MODULE_ALIAS_NFT_OBJ(type) \
MODULE_ALIAS("nft-obj-" __stringify(type))
/*
* The gencursor defines two generations, the currently active and the
* next one. Objects contain a bitmask of 2 bits specifying the generations
* they're active in. A set bit means they're inactive in the generation
* represented by that bit.
*
* New objects start out as inactive in the current and active in the
* next generation. When committing the ruleset the bitmask is cleared,
* meaning they're active in all generations. When removing an object,
* it is set inactive in the next generation. After committing the ruleset,
* the objects are removed.
*/
static inline unsigned int nft_gencursor_next(const struct net *net)
{
return net->nft.gencursor + 1 == 1 ? 1 : 0;
}
static inline u8 nft_genmask_next(const struct net *net)
{
return 1 << nft_gencursor_next(net);
}
static inline u8 nft_genmask_cur(const struct net *net)
{
/* Use ACCESS_ONCE() to prevent refetching the value for atomicity */
return 1 << ACCESS_ONCE(net->nft.gencursor);
}
#define NFT_GENMASK_ANY ((1 << 0) | (1 << 1))
/*
* Generic transaction helpers
*/
/* Check if this object is currently active. */
#define nft_is_active(__net, __obj) \
(((__obj)->genmask & nft_genmask_cur(__net)) == 0)
/* Check if this object is active in the next generation. */
#define nft_is_active_next(__net, __obj) \
(((__obj)->genmask & nft_genmask_next(__net)) == 0)
/* This object becomes active in the next generation. */
#define nft_activate_next(__net, __obj) \
(__obj)->genmask = nft_genmask_cur(__net)
/* This object becomes inactive in the next generation. */
#define nft_deactivate_next(__net, __obj) \
(__obj)->genmask = nft_genmask_next(__net)
/* After committing the ruleset, clear the stale generation bit. */
#define nft_clear(__net, __obj) \
(__obj)->genmask &= ~nft_genmask_next(__net)
#define nft_active_genmask(__obj, __genmask) \
!((__obj)->genmask & __genmask)
/*
* Set element transaction helpers
*/
static inline bool nft_set_elem_active(const struct nft_set_ext *ext,
u8 genmask)
{
return !(ext->genmask & genmask);
}
static inline void nft_set_elem_change_active(const struct net *net,
const struct nft_set *set,
struct nft_set_ext *ext)
{
ext->genmask ^= nft_genmask_next(net);
}
/*
* We use a free bit in the genmask field to indicate the element
* is busy, meaning it is currently being processed either by
* the netlink API or GC.
*
* Even though the genmask is only a single byte wide, this works
* because the extension structure if fully constant once initialized,
* so there are no non-atomic write accesses unless it is already
* marked busy.
*/
#define NFT_SET_ELEM_BUSY_MASK (1 << 2)
#if defined(__LITTLE_ENDIAN_BITFIELD)
#define NFT_SET_ELEM_BUSY_BIT 2
#elif defined(__BIG_ENDIAN_BITFIELD)
#define NFT_SET_ELEM_BUSY_BIT (BITS_PER_LONG - BITS_PER_BYTE + 2)
#else
#error
#endif
static inline int nft_set_elem_mark_busy(struct nft_set_ext *ext)
{
unsigned long *word = (unsigned long *)ext;
BUILD_BUG_ON(offsetof(struct nft_set_ext, genmask) != 0);
return test_and_set_bit(NFT_SET_ELEM_BUSY_BIT, word);
}
static inline void nft_set_elem_clear_busy(struct nft_set_ext *ext)
{
unsigned long *word = (unsigned long *)ext;
clear_bit(NFT_SET_ELEM_BUSY_BIT, word);
}
/**
* struct nft_trans - nf_tables object update in transaction
*
* @list: used internally
* @msg_type: message type
* @ctx: transaction context
* @data: internal information related to the transaction
*/
struct nft_trans {
struct list_head list;
int msg_type;
struct nft_ctx ctx;
char data[0];
};
struct nft_trans_rule {
struct nft_rule *rule;
u32 rule_id;
};
#define nft_trans_rule(trans) \
(((struct nft_trans_rule *)trans->data)->rule)
#define nft_trans_rule_id(trans) \
(((struct nft_trans_rule *)trans->data)->rule_id)
struct nft_trans_set {
struct nft_set *set;
u32 set_id;
};
#define nft_trans_set(trans) \
(((struct nft_trans_set *)trans->data)->set)
#define nft_trans_set_id(trans) \
(((struct nft_trans_set *)trans->data)->set_id)
struct nft_trans_chain {
bool update;
char name[NFT_CHAIN_MAXNAMELEN];
struct nft_stats __percpu *stats;
u8 policy;
};
#define nft_trans_chain_update(trans) \
(((struct nft_trans_chain *)trans->data)->update)
#define nft_trans_chain_name(trans) \
(((struct nft_trans_chain *)trans->data)->name)
#define nft_trans_chain_stats(trans) \
(((struct nft_trans_chain *)trans->data)->stats)
#define nft_trans_chain_policy(trans) \
(((struct nft_trans_chain *)trans->data)->policy)
struct nft_trans_table {
bool update;
bool enable;
};
#define nft_trans_table_update(trans) \
(((struct nft_trans_table *)trans->data)->update)
#define nft_trans_table_enable(trans) \
(((struct nft_trans_table *)trans->data)->enable)
struct nft_trans_elem {
struct nft_set *set;
struct nft_set_elem elem;
};
#define nft_trans_elem_set(trans) \
(((struct nft_trans_elem *)trans->data)->set)
#define nft_trans_elem(trans) \
(((struct nft_trans_elem *)trans->data)->elem)
struct nft_trans_obj {
struct nft_object *obj;
};
#define nft_trans_obj(trans) \
(((struct nft_trans_obj *)trans->data)->obj)
#endif /* _NET_NF_TABLES_H */