bird/filter/data.h
2022-02-06 23:42:10 +01:00

304 lines
7.9 KiB
C

/*
* BIRD Internet Routing Daemon -- Dynamic data structures
*
* (c) 1999 Pavel Machek <pavel@ucw.cz>
* (c) 2018--2019 Maria Matejka <mq@jmq.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_FILTER_DATA_H_
#define _BIRD_FILTER_DATA_H_
#include "nest/bird.h"
/* Type numbers must be in 0..0xff range */
#define T_MASK 0xff
/* Internal types */
enum f_type {
/* Nothing. Simply nothing. */
T_VOID = 0,
/* User visible types, which fit in int */
T_INT = 0x10,
T_BOOL = 0x11,
T_PAIR = 0x12, /* Notice that pair is stored as integer: first << 16 | second */
T_QUAD = 0x13,
/* Put enumerational types in 0x30..0x3f range */
T_ENUM_LO = 0x30,
T_ENUM_HI = 0x3f,
T_ENUM_RTS = 0x30,
T_ENUM_BGP_ORIGIN = 0x31,
T_ENUM_SCOPE = 0x32,
T_ENUM_RTC = 0x33,
T_ENUM_RTD = 0x34,
T_ENUM_ROA = 0x35,
T_ENUM_NETTYPE = 0x36,
T_ENUM_RA_PREFERENCE = 0x37,
T_ENUM_AF = 0x38,
/* new enums go here */
T_ENUM_EMPTY = 0x3f, /* Special hack for atomic_aggr */
#define T_ENUM T_ENUM_LO ... T_ENUM_HI
/* Bigger ones */
T_IP = 0x20,
T_NET = 0x21,
T_STRING = 0x22,
T_PATH_MASK = 0x23, /* mask for BGP path */
T_PATH = 0x24, /* BGP path */
T_CLIST = 0x25, /* Community list */
T_EC = 0x26, /* Extended community value, u64 */
T_ECLIST = 0x27, /* Extended community list */
T_LC = 0x28, /* Large community value, lcomm */
T_LCLIST = 0x29, /* Large community list */
T_RD = 0x2a, /* Route distinguisher for VPN addresses */
T_PATH_MASK_ITEM = 0x2b, /* Path mask item for path mask constructors */
T_SET = 0x80,
T_PREFIX_SET = 0x81,
} PACKED;
/* Filter value; size of this affects filter memory consumption */
struct f_val {
enum f_type type; /* T_* */
union {
uint i;
u64 ec;
lcomm lc;
ip_addr ip;
const net_addr *net;
const char *s;
const struct f_tree *t;
const struct f_trie *ti;
const struct adata *ad;
const struct f_path_mask *path_mask;
struct f_path_mask_item pmi;
} val;
};
/* Dynamic attribute definition (eattrs) */
struct f_dynamic_attr {
u8 type; /* EA type (EAF_*) */
u8 bit; /* For bitfield accessors */
enum f_type f_type; /* Filter type */
uint ea_code; /* EA code */
};
enum f_sa_code {
SA_FROM = 1,
SA_GW,
SA_NET,
SA_PROTO,
SA_SOURCE,
SA_SCOPE,
SA_DEST,
SA_IFNAME,
SA_IFINDEX,
SA_WEIGHT,
SA_GW_MPLS,
} PACKED;
/* Static attribute definition (members of struct rta) */
struct f_static_attr {
enum f_type f_type; /* Filter type */
enum f_sa_code sa_code; /* Static attribute id */
int readonly:1; /* Don't allow writing */
};
/* Filter l-value type */
enum f_lval_type {
F_LVAL_VARIABLE,
F_LVAL_PREFERENCE,
F_LVAL_SA,
F_LVAL_EA,
};
/* Filter l-value */
struct f_lval {
enum f_lval_type type;
union {
struct symbol *sym;
struct f_dynamic_attr da;
struct f_static_attr sa;
};
};
/* IP prefix range structure */
struct f_prefix {
net_addr net; /* The matching prefix must match this net */
u8 lo, hi; /* And its length must fit between lo and hi */
};
struct f_tree {
struct f_tree *left, *right;
struct f_val from, to;
void *data;
};
#define TRIE_STEP 4
#define TRIE_STACK_LENGTH 33
struct f_trie_node4
{
ip4_addr addr, mask, accept;
u16 plen;
u16 local;
struct f_trie_node4 *c[1 << TRIE_STEP];
};
struct f_trie_node6
{
ip6_addr addr, mask, accept;
u16 plen;
u16 local;
struct f_trie_node6 *c[1 << TRIE_STEP];
};
struct f_trie_node
{
union {
struct f_trie_node4 v4;
struct f_trie_node6 v6;
};
};
struct f_trie
{
linpool *lp;
u8 zero;
s8 ipv4; /* -1 for undefined / empty */
u16 data_size; /* Additional data for each trie node */
u32 prefix_count; /* Works only for restricted tries (pxlen == l == h) */
struct f_trie_node root; /* Root trie node */
};
struct f_trie_walk_state
{
u8 ipv4;
u8 accept_length; /* Current inter-node prefix position */
u8 start_pos; /* Initial prefix position in stack[0] */
u8 local_pos; /* Current intra-node prefix position */
u8 stack_pos; /* Current node in stack below */
const struct f_trie_node *stack[TRIE_STACK_LENGTH];
};
struct f_tree *f_new_tree(void);
struct f_tree *build_tree(struct f_tree *);
const struct f_tree *find_tree(const struct f_tree *t, const struct f_val *val);
int same_tree(const struct f_tree *t0, const struct f_tree *t2);
void tree_format(const struct f_tree *t, buffer *buf);
void tree_walk(const struct f_tree *t, void (*hook)(const struct f_tree *, void *), void *data);
struct f_trie *f_new_trie(linpool *lp, uint data_size);
void *trie_add_prefix(struct f_trie *t, const net_addr *n, uint l, uint h);
int trie_match_net(const struct f_trie *t, const net_addr *n);
int trie_match_longest_ip4(const struct f_trie *t, const net_addr_ip4 *net, net_addr_ip4 *dst, ip4_addr *found0);
int trie_match_longest_ip6(const struct f_trie *t, const net_addr_ip6 *net, net_addr_ip6 *dst, ip6_addr *found0);
void trie_walk_init(struct f_trie_walk_state *s, const struct f_trie *t, const net_addr *from);
int trie_walk_next(struct f_trie_walk_state *s, net_addr *net);
int trie_same(const struct f_trie *t1, const struct f_trie *t2);
void trie_format(const struct f_trie *t, buffer *buf);
static inline int
trie_match_next_longest_ip4(net_addr_ip4 *n, ip4_addr *found)
{
while (n->pxlen)
{
n->pxlen--;
ip4_clrbit(&n->prefix, n->pxlen);
if (ip4_getbit(*found, n->pxlen))
return 1;
}
return 0;
}
static inline int
trie_match_next_longest_ip6(net_addr_ip6 *n, ip6_addr *found)
{
while (n->pxlen)
{
n->pxlen--;
ip6_clrbit(&n->prefix, n->pxlen);
if (ip6_getbit(*found, n->pxlen))
return 1;
}
return 0;
}
#define TRIE_WALK_TO_ROOT_IP4(trie, net, dst) ({ \
net_addr_ip4 dst; \
ip4_addr _found; \
for (int _n = trie_match_longest_ip4(trie, net, &dst, &_found); \
_n; \
_n = trie_match_next_longest_ip4(&dst, &_found))
#define TRIE_WALK_TO_ROOT_IP6(trie, net, dst) ({ \
net_addr_ip6 dst; \
ip6_addr _found; \
for (int _n = trie_match_longest_ip6(trie, net, &dst, &_found); \
_n; \
_n = trie_match_next_longest_ip6(&dst, &_found))
#define TRIE_WALK_TO_ROOT_END })
#define TRIE_WALK(trie, net, from) ({ \
net_addr net; \
struct f_trie_walk_state tws_; \
trie_walk_init(&tws_, trie, from); \
while (trie_walk_next(&tws_, &net))
#define TRIE_WALK_END })
#define F_CMP_ERROR 999
const char *f_type_name(enum f_type t);
enum f_type f_type_element_type(enum f_type t);
int val_same(const struct f_val *v1, const struct f_val *v2);
int val_compare(const struct f_val *v1, const struct f_val *v2);
void val_format(const struct f_val *v, buffer *buf);
char *val_format_str(struct linpool *lp, const struct f_val *v);
const char *val_dump(const struct f_val *v);
static inline int val_is_ip4(const struct f_val *v)
{ return (v->type == T_IP) && ipa_is_ip4(v->val.ip); }
int val_in_range(const struct f_val *v1, const struct f_val *v2);
int clist_set_type(const struct f_tree *set, struct f_val *v);
static inline int eclist_set_type(const struct f_tree *set)
{ return set->from.type == T_EC; }
static inline int lclist_set_type(const struct f_tree *set)
{ return set->from.type == T_LC; }
const struct adata *clist_filter(struct linpool *pool, const struct adata *list, const struct f_val *set, int pos);
const struct adata *eclist_filter(struct linpool *pool, const struct adata *list, const struct f_val *set, int pos);
const struct adata *lclist_filter(struct linpool *pool, const struct adata *list, const struct f_val *set, int pos);
/* Special undef value for paths and clists */
static inline int
undef_value(struct f_val v)
{
return ((v.type == T_PATH) || (v.type == T_CLIST) ||
(v.type == T_ECLIST) || (v.type == T_LCLIST)) &&
(v.val.ad == &null_adata);
}
extern const struct f_val f_const_empty_path, f_const_empty_clist, f_const_empty_eclist, f_const_empty_lclist;
enum filter_return f_eval(const struct f_line *expr, struct linpool *tmp_pool, struct f_val *pres);
#endif