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 struct f_prefix {
  36   ip_addr ip;
  37   int len;
  38 #define LEN_MASK 0xff
  39 #define LEN_PLUS  0x1000000
  40 #define LEN_MINUS 0x2000000
  41 #define LEN_RANGE 0x4000000
  42   /* If range then prefix must be in range (len >> 16 & 0xff, len >> 8 & 0xff) */
  43 };
  44
  45 struct f_val {
  46   int type;
  47   union {
  48     int i;
  49     /*    ip_addr ip; Folded into prefix */
  50     struct f_prefix px;
  51     char *s;
  52     struct f_tree *t;
  53     struct f_trie *ti;
  54     struct adata *ad;
  55     struct f_path_mask *path_mask;
  56   } val;
  57 };
  58
  59 struct filter {
  60   char *name;
  61   struct f_inst *root;
  62 };
  63
  64 struct f_inst *f_new_inst(void);
  65 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 */
  66 struct f_tree *f_new_tree(void);
  67 struct f_inst *f_generate_complex(int operation, int operation_aux, struct f_inst *dyn, struct f_inst *argument);
  68
  69 struct f_tree *build_tree(struct f_tree *);
  70 struct f_tree *find_tree(struct f_tree *t, struct f_val val);
  71 int same_tree(struct f_tree *t1, struct f_tree *t2);
  72
  73 struct f_trie *f_new_trie(void);
  74 void trie_add_prefix(struct f_trie *t, struct f_prefix *px);
  75 int trie_match_prefix(struct f_trie *t, struct f_prefix *px);
  76 int trie_same(struct f_trie *t1, struct f_trie *t2);
  77 int trie_print(struct f_trie *t, char *buf, int blen);
  78
  79 struct ea_list;
  80 struct rte;
  81
  82 int f_run(struct filter *filter, struct rte **rte, struct ea_list **tmp_attrs, struct linpool *tmp_pool, int flags);
  83 int f_eval_int(struct f_inst *expr);
  84 u32 f_eval_asn(struct f_inst *expr);
  85
  86 char *filter_name(struct filter *filter);
  87 int filter_same(struct filter *new, struct filter *old);
  88
  89 int i_same(struct f_inst *f1, struct f_inst *f2);
  90 void f_prefix_get_bounds(struct f_prefix *px, int *l, int *h);
  91
  92 int val_compare(struct f_val v1, struct f_val v2);
  93 void val_print(struct f_val v);
  94
  95 #define F_NOP 0
  96 #define F_NONL 1
  97 #define F_ACCEPT 2      /* Need to preserve ordering: accepts < rejects! */
  98 #define F_REJECT 3
  99 #define F_ERROR 4
 100 #define F_QUITBIRD 5
 101
 102 #define FILTER_ACCEPT NULL
 103 #define FILTER_REJECT ((void *) 1)
 104
 105 /* Type numbers must be in 0..0xff range */
 106 #define T_MASK 0xff
 107
 108 /* Internal types */
 109 /* Do not use type of zero, that way we'll see errors easier. */
 110 #define T_VOID 1
 111
 112 /* User visible types, which fit in int */
 113 #define T_INT 0x10
 114 #define T_BOOL 0x11
 115 #define T_PAIR 0x12  /* Notice that pair is stored as integer: first << 16 | second */
 116
 117 /* Put enumerational types in 0x30..0x3f range */
 118 #define T_ENUM_LO 0x30
 119 #define T_ENUM_HI 0x3f
 120
 121 #define T_ENUM_RTS 0x30
 122 #define T_ENUM_BGP_ORIGIN 0x31
 123 #define T_ENUM_SCOPE 0x32
 124 #define T_ENUM_RTC 0x33
 125 #define T_ENUM_RTD 0x34
 126 /* new enums go here */
 127 #define T_ENUM_EMPTY 0x3f       /* Special hack for atomic_aggr */
 128
 129 #define T_ENUM T_ENUM_LO ... T_ENUM_HI
 130
 131 /* Bigger ones */
 132 #define T_IP 0x20
 133 #define T_PREFIX 0x21
 134 #define T_STRING 0x22
 135 #define T_PATH_MASK 0x23        /* mask for BGP path */
 136 #define T_PATH 0x24             /* BGP path */
 137 #define T_CLIST 0x25            /* Community list */
 138
 139 #define T_RETURN 0x40
 140 #define T_SET 0x80
 141 #define T_PREFIX_SET 0x81
 142
 143 struct f_tree {
 144   struct f_tree *left, *right;
 145   struct f_val from, to;
 146   void *data;
 147 };
 148
 149 struct f_trie_node
 150 {
 151   ip_addr addr, mask, accept;
 152   int plen;
 153   struct f_trie_node *c[2];
 154 };
 155
 156 struct f_trie
 157 {
 158   int zero;
 159   struct f_trie_node root;
 160 };
 161
 162 #define NEW_F_VAL struct f_val * val; val = cfg_alloc(sizeof(struct f_val));
 163
 164 #define FF_FORCE_TMPATTR 1              /* Force all attributes to be temporary */
 165
 166 #endif