filter/filter.h

   1 /*
   2  *      BIRD Internet Routing Daemon -- Filters
   3  *
   4  *      (c) 1999 Pavel Machek <pavel@ucw.cz>
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL.
   7  */
   8
   9 #ifndef _BIRD_FILT_H_
  10 #define _BIRD_FILT_H_
  11
  12 #include "lib/resource.h"
  13 #include "lib/ip.h"
  14 #include "nest/route.h"
  15 #include "nest/attrs.h"
  16
  17 struct f_inst {         /* Instruction */
  18   struct f_inst *next;  /* Structure is 16 bytes, anyway */
  19   u16 code;
  20   u16 aux;
  21   union {
  22     int i;
  23     void *p;
  24   } a1;
  25   union {
  26     int i;
  27     void *p;
  28   } a2;
  29   int lineno;
  30 };
  31
  32 #define arg1 a1.p
  33 #define arg2 a2.p
  34
  35 /* Not enough fields in f_inst for three args used by roa_check() */
  36 struct f_inst_roa_check {
  37   struct f_inst i;
  38   struct roa_table_config *rtc;
  39 };
  40
  41 struct f_prefix {
  42   ip_addr ip;
  43   int len;
  44 #define LEN_MASK 0xff
  45 #define LEN_PLUS  0x1000000
  46 #define LEN_MINUS 0x2000000
  47 #define LEN_RANGE 0x4000000
  48   /* If range then prefix must be in range (len >> 16 & 0xff, len >> 8 & 0xff) */
  49 };
  50
  51 struct f_val {
  52   int type;
  53   union {
  54     int i;
  55     u64 ec;
  56     /*    ip_addr ip; Folded into prefix */
  57     struct f_prefix px;
  58     char *s;
  59     struct f_tree *t;
  60     struct f_trie *ti;
  61     struct adata *ad;
  62     struct f_path_mask *path_mask;
  63   } val;
  64 };
  65
  66 struct filter {
  67   char *name;
  68   struct f_inst *root;
  69 };
  70
  71 struct f_inst *f_new_inst(void);
  72 struct f_inst *f_new_dynamic_attr(int type, int f_type, int code);      /* Type as core knows it, type as filters know it, and code of dynamic attribute */
  73 struct f_tree *f_new_tree(void);
  74 struct f_inst *f_generate_complex(int operation, int operation_aux, struct f_inst *dyn, struct f_inst *argument);
  75 struct f_inst *f_generate_roa_check(struct symbol *sym, struct f_inst *prefix, struct f_inst *asn);
  76
  77
  78 struct f_tree *build_tree(struct f_tree *);
  79 struct f_tree *find_tree(struct f_tree *t, struct f_val val);
  80 int same_tree(struct f_tree *t1, struct f_tree *t2);
  81
  82 struct f_trie *f_new_trie(linpool *lp);
  83 void trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h);
  84 int trie_match_prefix(struct f_trie *t, ip_addr px, int plen);
  85 int trie_same(struct f_trie *t1, struct f_trie *t2);
  86 void trie_print(struct f_trie *t);
  87
  88 void fprefix_get_bounds(struct f_prefix *px, int *l, int *h);
  89
  90 static inline void
  91 trie_add_fprefix(struct f_trie *t, struct f_prefix *px)
  92 {
  93   int l, h;
  94   fprefix_get_bounds(px, &l, &h);
  95   trie_add_prefix(t, px->ip, px->len & LEN_MASK, l, h);
  96 }
  97
  98 static inline int
  99 trie_match_fprefix(struct f_trie *t, struct f_prefix *px)
 100 {
 101   return trie_match_prefix(t, px->ip, px->len & LEN_MASK);
 102 }
 103
 104
 105 struct ea_list;
 106 struct rte;
 107
 108 int f_run(struct filter *filter, struct rte **rte, struct ea_list **tmp_attrs, struct linpool *tmp_pool, int flags);
 109 int f_eval_int(struct f_inst *expr);
 110 u32 f_eval_asn(struct f_inst *expr);
 111
 112 char *filter_name(struct filter *filter);
 113 int filter_same(struct filter *new, struct filter *old);
 114
 115 int i_same(struct f_inst *f1, struct f_inst *f2);
 116
 117 int val_compare(struct f_val v1, struct f_val v2);
 118 int tree_compare(const void *p1, const void *p2);
 119
 120 #define F_NOP 0
 121 #define F_NONL 1
 122 #define F_ACCEPT 2      /* Need to preserve ordering: accepts < rejects! */
 123 #define F_REJECT 3
 124 #define F_ERROR 4
 125 #define F_QUITBIRD 5
 126
 127 #define FILTER_ACCEPT NULL
 128 #define FILTER_REJECT ((void *) 1)
 129
 130 /* Type numbers must be in 0..0xff range */
 131 #define T_MASK 0xff
 132
 133 /* Internal types */
 134 /* Do not use type of zero, that way we'll see errors easier. */
 135 #define T_VOID 1
 136
 137 /* User visible types, which fit in int */
 138 #define T_INT 0x10
 139 #define T_BOOL 0x11
 140 #define T_PAIR 0x12  /* Notice that pair is stored as integer: first << 16 | second */
 141 #define T_QUAD 0x13
 142
 143 /* Put enumerational types in 0x30..0x3f range */
 144 #define T_ENUM_LO 0x30
 145 #define T_ENUM_HI 0x3f
 146
 147 #define T_ENUM_RTS 0x30
 148 #define T_ENUM_BGP_ORIGIN 0x31
 149 #define T_ENUM_SCOPE 0x32
 150 #define T_ENUM_RTC 0x33
 151 #define T_ENUM_RTD 0x34
 152 #define T_ENUM_ROA 0x35
 153 /* new enums go here */
 154 #define T_ENUM_EMPTY 0x3f       /* Special hack for atomic_aggr */
 155
 156 #define T_ENUM T_ENUM_LO ... T_ENUM_HI
 157
 158 /* Bigger ones */
 159 #define T_IP 0x20
 160 #define T_PREFIX 0x21
 161 #define T_STRING 0x22
 162 #define T_PATH_MASK 0x23        /* mask for BGP path */
 163 #define T_PATH 0x24             /* BGP path */
 164 #define T_CLIST 0x25            /* Community list */
 165 #define T_ECLIST 0x26           /* Extended community list */
 166 #define T_EC 0x27               /* Extended community value, u64 */
 167
 168 #define T_RETURN 0x40
 169 #define T_SET 0x80
 170 #define T_PREFIX_SET 0x81
 171
 172 struct f_tree {
 173   struct f_tree *left, *right;
 174   struct f_val from, to;
 175   void *data;
 176 };
 177
 178 struct f_trie_node
 179 {
 180   ip_addr addr, mask, accept;
 181   int plen;
 182   struct f_trie_node *c[2];
 183 };
 184
 185 struct f_trie
 186 {
 187   linpool *lp;
 188   int zero;
 189   struct f_trie_node root;
 190 };
 191
 192 #define NEW_F_VAL struct f_val * val; val = cfg_alloc(sizeof(struct f_val));
 193
 194 #define FF_FORCE_TMPATTR 1              /* Force all attributes to be temporary */
 195
 196 #endif