mirror of
https://gitlab.nic.cz/labs/bird.git
synced 2024-12-22 01:31:55 +00:00
900 lines
23 KiB
C
900 lines
23 KiB
C
/*
|
|
* Filters: utility functions
|
|
*
|
|
* Copyright 1998 Pavel Machek <pavel@ucw.cz>
|
|
*
|
|
* Can be freely distributed and used under the terms of the GNU GPL.
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* DOC: Filters
|
|
*
|
|
* You can find sources of the filter language in |filter/|
|
|
* directory. File |filter/config.Y| contains filter grammar and basically translates
|
|
* the source from user into a tree of &f_inst structures. These trees are
|
|
* later interpreted using code in |filter/filter.c|.
|
|
*
|
|
* A filter is represented by a tree of &f_inst structures, one structure per
|
|
* "instruction". Each &f_inst contains @code, @aux value which is
|
|
* usually the data type this instruction operates on and two generic
|
|
* arguments (@a1, @a2). Some instructions contain pointer(s) to other
|
|
* instructions in their (@a1, @a2) fields.
|
|
*
|
|
* Filters use a &f_val structure for their data. Each &f_val
|
|
* contains type and value (types are constants prefixed with %T_). Few
|
|
* of the types are special; %T_RETURN can be or-ed with a type to indicate
|
|
* that return from a function or from the whole filter should be
|
|
* forced. Important thing about &f_val's is that they may be copied
|
|
* with a simple |=|. That's fine for all currently defined types: strings
|
|
* are read-only (and therefore okay), paths are copied for each
|
|
* operation (okay too).
|
|
*/
|
|
|
|
#undef LOCAL_DEBUG
|
|
|
|
#include "nest/bird.h"
|
|
#include "lib/lists.h"
|
|
#include "lib/resource.h"
|
|
#include "lib/socket.h"
|
|
#include "lib/string.h"
|
|
#include "lib/unaligned.h"
|
|
#include "nest/route.h"
|
|
#include "nest/protocol.h"
|
|
#include "nest/iface.h"
|
|
#include "nest/attrs.h"
|
|
#include "conf/conf.h"
|
|
#include "filter/filter.h"
|
|
|
|
#define P(a,b) ((a<<8) | b)
|
|
|
|
#define CMP_ERROR 999
|
|
|
|
static struct adata *
|
|
adata_empty(struct linpool *pool)
|
|
{
|
|
struct adata *res = lp_alloc(pool, sizeof(struct adata));
|
|
res->length = 0;
|
|
return res;
|
|
}
|
|
|
|
static int
|
|
pm_path_compare(struct f_path_mask *m1, struct f_path_mask *m2)
|
|
{
|
|
while (1) {
|
|
if ((!m1) || (!m2))
|
|
return !((!m1) && (!m2));
|
|
m1 = m1->next;
|
|
m2 = m2->next;
|
|
}
|
|
}
|
|
|
|
static void
|
|
pm_format(struct f_path_mask *p, byte *buf, unsigned int size)
|
|
{
|
|
byte *end = buf + size - 16;
|
|
|
|
while (p)
|
|
{
|
|
if (buf > end)
|
|
{
|
|
strcpy(buf, " ...");
|
|
return;
|
|
}
|
|
|
|
if (p->any)
|
|
buf += bsprintf(buf, "? ");
|
|
else
|
|
buf += bsprintf(buf, "%u ", p->val);
|
|
|
|
p = p->next;
|
|
}
|
|
|
|
*buf = 0;
|
|
}
|
|
|
|
/**
|
|
* val_compare - compare two values
|
|
* @v1: first value
|
|
* @v2: second value
|
|
*
|
|
* Compares two values and returns -1, 0, 1 on <, =, > or 999 on error.
|
|
* Tree module relies on this giving consistent results so that it can
|
|
* build balanced trees.
|
|
*/
|
|
int
|
|
val_compare(struct f_val v1, struct f_val v2)
|
|
{
|
|
int rc;
|
|
|
|
if ((v1.type == T_VOID) && (v2.type == T_VOID))
|
|
return 0;
|
|
if (v1.type == T_VOID) /* Hack for else */
|
|
return -1;
|
|
if (v2.type == T_VOID)
|
|
return 1;
|
|
|
|
if (v1.type != v2.type) {
|
|
debug( "Types do not match in val_compare\n" );
|
|
return CMP_ERROR;
|
|
}
|
|
switch (v1.type) {
|
|
case T_ENUM:
|
|
case T_INT:
|
|
case T_PAIR:
|
|
if (v1.val.i == v2.val.i) return 0;
|
|
if (v1.val.i < v2.val.i) return -1;
|
|
return 1;
|
|
case T_IP:
|
|
return ipa_compare(v1.val.px.ip, v2.val.px.ip);
|
|
case T_PREFIX:
|
|
if (rc = ipa_compare(v1.val.px.ip, v2.val.px.ip))
|
|
return rc;
|
|
if (v1.val.px.len < v2.val.px.len)
|
|
return -1;
|
|
if (v1.val.px.len > v2.val.px.len)
|
|
return 1;
|
|
return 0;
|
|
case T_PATH_MASK:
|
|
return pm_path_compare(v1.val.path_mask, v2.val.path_mask);
|
|
default:
|
|
debug( "Compare of unkown entities: %x\n", v1.type );
|
|
return CMP_ERROR;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* val_simple_in_range - check if @v1 ~ @v2 for everything except sets
|
|
*/
|
|
static int
|
|
val_simple_in_range(struct f_val v1, struct f_val v2)
|
|
{
|
|
if ((v1.type == T_PATH) && (v2.type == T_PATH_MASK))
|
|
return as_path_match(v1.val.ad, v2.val.path_mask);
|
|
if ((v1.type == T_PAIR) && (v2.type == T_CLIST))
|
|
return int_set_contains(v2.val.ad, v1.val.i);
|
|
|
|
if ((v1.type == T_IP) && (v2.type == T_PREFIX))
|
|
return !(ipa_compare(ipa_and(v2.val.px.ip, ipa_mkmask(v2.val.px.len)), ipa_and(v1.val.px.ip, ipa_mkmask(v2.val.px.len))));
|
|
|
|
if ((v1.type == T_PREFIX) && (v2.type == T_PREFIX)) {
|
|
ip_addr mask;
|
|
if (v1.val.px.len & (LEN_PLUS | LEN_MINUS | LEN_RANGE))
|
|
return CMP_ERROR;
|
|
mask = ipa_mkmask( v2.val.px.len & LEN_MASK );
|
|
if (ipa_compare(ipa_and(v2.val.px.ip, mask), ipa_and(v1.val.px.ip, mask)))
|
|
return 0;
|
|
|
|
if ((v2.val.px.len & LEN_MINUS) && (v1.val.px.len <= (v2.val.px.len & LEN_MASK)))
|
|
return 0;
|
|
if ((v2.val.px.len & LEN_PLUS) && (v1.val.px.len < (v2.val.px.len & LEN_MASK)))
|
|
return 0;
|
|
if ((v2.val.px.len & LEN_RANGE) && ((v1.val.px.len < (0xff & (v2.val.px.len >> 16)))
|
|
|| (v1.val.px.len > (0xff & (v2.val.px.len >> 8)))))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
return CMP_ERROR;
|
|
}
|
|
|
|
/**
|
|
* val_in_range - implement |~| operator
|
|
* @v1: element
|
|
* @v2: set
|
|
*
|
|
* Checks if @v1 is element (|~| operator) of @v2. Sets are internally represented as balanced trees, see
|
|
* |tree.c| module (this is not limited to sets, but for non-set cases, val_simple_in_range() is called early).
|
|
*/
|
|
static int
|
|
val_in_range(struct f_val v1, struct f_val v2)
|
|
{
|
|
int res;
|
|
|
|
res = val_simple_in_range(v1, v2);
|
|
|
|
if (res != CMP_ERROR)
|
|
return res;
|
|
|
|
if (v2.type == T_SET)
|
|
switch (v1.type) {
|
|
case T_ENUM:
|
|
case T_INT:
|
|
case T_IP:
|
|
case T_PREFIX:
|
|
{
|
|
struct f_tree *n;
|
|
n = find_tree(v2.val.t, v1);
|
|
if (!n)
|
|
return 0;
|
|
return !! (val_simple_in_range(v1, n->from)); /* We turn CMP_ERROR into compared ok, and that's fine */
|
|
}
|
|
}
|
|
return CMP_ERROR;
|
|
}
|
|
|
|
static void
|
|
tree_print(struct f_tree *t)
|
|
{
|
|
if (!t) {
|
|
debug( "() " );
|
|
return;
|
|
}
|
|
debug( "[ " );
|
|
tree_print( t->left );
|
|
debug( ", " ); val_print( t->from ); debug( ".." ); val_print( t->to ); debug( ", " );
|
|
tree_print( t->right );
|
|
debug( "] " );
|
|
}
|
|
|
|
/*
|
|
* val_print - format filter value
|
|
*/
|
|
void
|
|
val_print(struct f_val v)
|
|
{
|
|
char buf[2048];
|
|
char buf2[1024];
|
|
#define PRINTF(a...) bsnprintf( buf, 2040, a )
|
|
buf[0] = 0;
|
|
switch (v.type) {
|
|
case T_VOID: PRINTF( "(void)" ); break;
|
|
case T_BOOL: PRINTF( v.val.i ? "TRUE" : "FALSE" ); break;
|
|
case T_INT: PRINTF( "%d ", v.val.i ); break;
|
|
case T_STRING: PRINTF( "%s", v.val.s ); break;
|
|
case T_IP: PRINTF( "%I", v.val.px.ip ); break;
|
|
case T_PREFIX: PRINTF( "%I/%d", v.val.px.ip, v.val.px.len ); break;
|
|
case T_PAIR: PRINTF( "(%d,%d)", v.val.i >> 16, v.val.i & 0xffff ); break;
|
|
case T_SET: tree_print( v.val.t ); PRINTF( "\n" ); break;
|
|
case T_ENUM: PRINTF( "(enum %x)%d", v.type, v.val.i ); break;
|
|
case T_PATH: as_path_format(v.val.ad, buf2, 1020); PRINTF( "(path %s)", buf2 ); break;
|
|
case T_CLIST: int_set_format(v.val.ad, buf2, 1020); PRINTF( "(clist %s)", buf2 ); break;
|
|
case T_PATH_MASK: pm_format(v.val.path_mask, buf2, 1020); PRINTF( "(pathmask %s)", buf2 ); break;
|
|
default: PRINTF( "[unknown type %x]", v.type );
|
|
#undef PRINTF
|
|
}
|
|
debug( buf );
|
|
}
|
|
|
|
static struct rte **f_rte, *f_rte_old;
|
|
static struct linpool *f_pool;
|
|
static struct ea_list **f_tmp_attrs;
|
|
static int f_flags;
|
|
static rta *f_rta_copy;
|
|
|
|
/*
|
|
* rta_cow - prepare rta for modification by filter
|
|
*/
|
|
static void
|
|
rta_cow(void)
|
|
{
|
|
if (!f_rta_copy) {
|
|
f_rta_copy = lp_alloc(f_pool, sizeof(rta));
|
|
memcpy(f_rta_copy, (*f_rte)->attrs, sizeof(rta));
|
|
f_rta_copy->aflags = 0;
|
|
*f_rte = rte_cow(*f_rte);
|
|
rta_free((*f_rte)->attrs);
|
|
(*f_rte)->attrs = f_rta_copy;
|
|
}
|
|
}
|
|
|
|
#define runtime(x) do { \
|
|
log( L_ERR "filters, line %d: %s", what->lineno, x); \
|
|
res.type = T_RETURN; \
|
|
res.val.i = F_ERROR; \
|
|
return res; \
|
|
} while(0)
|
|
|
|
#define ARG(x,y) \
|
|
x = interpret(what->y); \
|
|
if (x.type & T_RETURN) \
|
|
return x;
|
|
|
|
#define ONEARG ARG(v1, a1.p)
|
|
#define TWOARGS ARG(v1, a1.p) \
|
|
ARG(v2, a2.p)
|
|
#define TWOARGS_C TWOARGS \
|
|
if (v1.type != v2.type) \
|
|
runtime( "Can't operate with values of incompatible types" );
|
|
|
|
/**
|
|
* interpret
|
|
* @what: filter to interpret
|
|
*
|
|
* Interpret given tree of filter instructions. This is core function
|
|
* of filter system and does all the hard work.
|
|
*
|
|
* Each instruction has 4 fields: code (which is instruction code),
|
|
* aux (which is extension to instruction code, typically type),
|
|
* arg1 and arg2 - arguments. Depending on instruction, arguments
|
|
* are either integers, or pointers to instruction trees. Common
|
|
* instructions like +, that have two expressions as arguments use
|
|
* TWOARGS macro to get both of them evaluated.
|
|
*
|
|
* &f_val structures are copied around, so there are no problems with
|
|
* memory managment.
|
|
*/
|
|
static struct f_val
|
|
interpret(struct f_inst *what)
|
|
{
|
|
struct symbol *sym;
|
|
struct f_val v1, v2, res;
|
|
int i;
|
|
|
|
res.type = T_VOID;
|
|
if (!what)
|
|
return res;
|
|
|
|
switch(what->code) {
|
|
case ',':
|
|
TWOARGS;
|
|
break;
|
|
|
|
/* Binary operators */
|
|
case '+':
|
|
TWOARGS_C;
|
|
switch (res.type = v1.type) {
|
|
case T_VOID: runtime( "Can't operate with values of type void" );
|
|
case T_INT: res.val.i = v1.val.i + v2.val.i; break;
|
|
default: runtime( "Usage of unknown type" );
|
|
}
|
|
break;
|
|
case '-':
|
|
TWOARGS_C;
|
|
switch (res.type = v1.type) {
|
|
case T_VOID: runtime( "Can't operate with values of type void" );
|
|
case T_INT: res.val.i = v1.val.i - v2.val.i; break;
|
|
default: runtime( "Usage of unknown type" );
|
|
}
|
|
break;
|
|
case '*':
|
|
TWOARGS_C;
|
|
switch (res.type = v1.type) {
|
|
case T_VOID: runtime( "Can't operate with values of type void" );
|
|
case T_INT: res.val.i = v1.val.i * v2.val.i; break;
|
|
default: runtime( "Usage of unknown type" );
|
|
}
|
|
break;
|
|
case '/':
|
|
TWOARGS_C;
|
|
switch (res.type = v1.type) {
|
|
case T_VOID: runtime( "Can't operate with values of type void" );
|
|
case T_INT: if (v2.val.i == 0) runtime( "Mother told me not to divide by 0" );
|
|
res.val.i = v1.val.i / v2.val.i; break;
|
|
case T_IP: if (v2.type != T_INT)
|
|
runtime( "Incompatible types in / operator" );
|
|
break;
|
|
default: runtime( "Usage of unknown type" );
|
|
}
|
|
break;
|
|
|
|
case '&':
|
|
TWOARGS_C;
|
|
res.type = v1.type;
|
|
if (res.type != T_BOOL) runtime( "Can't do boolean operation on non-booleans" );
|
|
res.val.i = v1.val.i && v2.val.i;
|
|
break;
|
|
case '|':
|
|
TWOARGS_C;
|
|
res.type = v1.type;
|
|
if (res.type != T_BOOL) runtime( "Can't do boolean operation on non-booleans" );
|
|
res.val.i = v1.val.i || v2.val.i;
|
|
break;
|
|
|
|
/* Relational operators */
|
|
|
|
#define COMPARE(x) \
|
|
TWOARGS_C; \
|
|
res.type = T_BOOL; \
|
|
i = val_compare(v1, v2); \
|
|
if (i==CMP_ERROR) \
|
|
runtime( "Error in comparison" ); \
|
|
res.val.i = (x); \
|
|
break;
|
|
|
|
case P('!','='): COMPARE(i!=0);
|
|
case P('=','='): COMPARE(i==0);
|
|
case '<': COMPARE(i==-1);
|
|
case P('<','='): COMPARE(i!=1);
|
|
|
|
case '!':
|
|
ONEARG;
|
|
if (v1.type != T_BOOL)
|
|
runtime( "Not applied to non-boolean" );
|
|
res = v1;
|
|
res.val.i = !res.val.i;
|
|
break;
|
|
|
|
case '~':
|
|
TWOARGS;
|
|
res.type = T_BOOL;
|
|
res.val.i = val_in_range(v1, v2);
|
|
if (res.val.i == CMP_ERROR)
|
|
runtime( "~ applied on unknown type pair" );
|
|
break;
|
|
case P('d','e'):
|
|
ONEARG;
|
|
res.type = T_BOOL;
|
|
res.val.i = (v1.type != T_VOID);
|
|
break;
|
|
|
|
/* Set to indirect value, a1 = variable, a2 = value */
|
|
case 's':
|
|
ARG(v2, a2.p);
|
|
sym = what->a1.p;
|
|
switch (res.type = v2.type) {
|
|
case T_VOID: runtime( "Can't assign void values" );
|
|
case T_ENUM:
|
|
case T_INT:
|
|
case T_IP:
|
|
case T_PREFIX:
|
|
case T_PAIR:
|
|
case T_PATH:
|
|
case T_CLIST:
|
|
case T_PATH_MASK:
|
|
if (sym->class != (SYM_VARIABLE | v2.type))
|
|
runtime( "Assigning to variable of incompatible type" );
|
|
* (struct f_val *) sym->aux2 = v2;
|
|
break;
|
|
default:
|
|
bug( "Set to invalid type" );
|
|
}
|
|
break;
|
|
|
|
case 'c': /* integer (or simple type) constant */
|
|
res.type = what->aux;
|
|
res.val.i = what->a2.i;
|
|
break;
|
|
case 'C':
|
|
res = * ((struct f_val *) what->a1.p);
|
|
break;
|
|
case 'p':
|
|
ONEARG;
|
|
val_print(v1);
|
|
break;
|
|
case '?': /* ? has really strange error value, so we can implement if ... else nicely :-) */
|
|
ONEARG;
|
|
if (v1.type != T_BOOL)
|
|
runtime( "If requires boolean expression" );
|
|
if (v1.val.i) {
|
|
ARG(res,a2.p);
|
|
res.val.i = 0;
|
|
} else res.val.i = 1;
|
|
res.type = T_BOOL;
|
|
break;
|
|
case '0':
|
|
debug( "No operation\n" );
|
|
break;
|
|
case P('p',','):
|
|
ONEARG;
|
|
if (what->a2.i == F_NOP || (what->a2.i != F_NONL && what->a1.p))
|
|
debug( "\n" );
|
|
|
|
switch (what->a2.i) {
|
|
case F_QUITBIRD:
|
|
die( "Filter asked me to die" );
|
|
case F_ACCEPT:
|
|
/* Should take care about turning ACCEPT into MODIFY */
|
|
case F_ERROR:
|
|
case F_REJECT: /* FIXME (noncritical) Should print complete route along with reason to reject route */
|
|
res.type = T_RETURN;
|
|
res.val.i = what->a2.i;
|
|
return res; /* We have to return now, no more processing. */
|
|
case F_NONL:
|
|
case F_NOP:
|
|
break;
|
|
default:
|
|
bug( "unknown return type: Can't happen");
|
|
}
|
|
break;
|
|
case 'a': /* rta access */
|
|
{
|
|
struct rta *rta = (*f_rte)->attrs;
|
|
res.type = what->aux;
|
|
switch(res.type) {
|
|
case T_IP:
|
|
res.val.px.ip = * (ip_addr *) ((char *) rta + what->a2.i);
|
|
break;
|
|
case T_ENUM:
|
|
res.val.i = * ((char *) rta + what->a2.i);
|
|
break;
|
|
case T_PREFIX: /* Warning: this works only for prefix of network */
|
|
{
|
|
res.val.px.ip = (*f_rte)->net->n.prefix;
|
|
res.val.px.len = (*f_rte)->net->n.pxlen;
|
|
break;
|
|
}
|
|
default:
|
|
bug( "Invalid type for rta access (%x)", res.type );
|
|
}
|
|
}
|
|
break;
|
|
case P('a','S'):
|
|
ONEARG;
|
|
if (what->aux != v1.type)
|
|
runtime( "Attempt to set static attribute to incompatible type" );
|
|
rta_cow();
|
|
{
|
|
struct rta *rta = (*f_rte)->attrs;
|
|
switch (what->aux) {
|
|
case T_ENUM:
|
|
* ((char *) rta + what->a2.i) = v1.val.i;
|
|
break;
|
|
case T_IP:
|
|
* (ip_addr *) ((char *) rta + what->a2.i) = v1.val.px.ip;
|
|
break;
|
|
default:
|
|
bug( "Unknown type in set of static attribute" );
|
|
}
|
|
}
|
|
break;
|
|
case P('e','a'): /* Access to extended attributes */
|
|
{
|
|
eattr *e = NULL;
|
|
if (!(f_flags & FF_FORCE_TMPATTR))
|
|
e = ea_find( (*f_rte)->attrs->eattrs, what->a2.i );
|
|
if (!e)
|
|
e = ea_find( (*f_tmp_attrs), what->a2.i );
|
|
if ((!e) && (f_flags & FF_FORCE_TMPATTR))
|
|
e = ea_find( (*f_rte)->attrs->eattrs, what->a2.i );
|
|
|
|
switch (what->aux & EAF_TYPE_MASK) {
|
|
case EAF_TYPE_INT:
|
|
if (!e) {
|
|
res.type = T_VOID;
|
|
break;
|
|
}
|
|
res.type = T_INT;
|
|
res.val.i = e->u.data;
|
|
break;
|
|
case EAF_TYPE_AS_PATH:
|
|
if (!e) {
|
|
res.type = T_VOID;
|
|
break;
|
|
}
|
|
res.type = T_PATH;
|
|
res.val.ad = e->u.ptr;
|
|
break;
|
|
case EAF_TYPE_INT_SET:
|
|
if (!e) {
|
|
res.type = T_CLIST;
|
|
res.val.ad = adata_empty(f_pool);
|
|
break;
|
|
}
|
|
res.type = T_CLIST;
|
|
res.val.ad = e->u.ptr;
|
|
break;
|
|
default:
|
|
bug("Unknown type in e,a");
|
|
}
|
|
}
|
|
break;
|
|
case P('e','S'):
|
|
ONEARG;
|
|
{
|
|
struct ea_list *l = lp_alloc(f_pool, sizeof(struct ea_list) + sizeof(eattr));
|
|
|
|
l->next = NULL;
|
|
l->flags = EALF_SORTED;
|
|
l->count = 1;
|
|
l->attrs[0].id = what->a2.i;
|
|
l->attrs[0].flags = 0;
|
|
l->attrs[0].type = what->aux | EAF_ORIGINATED;
|
|
switch (what->aux & EAF_TYPE_MASK) {
|
|
case EAF_TYPE_INT:
|
|
if (v1.type != T_INT)
|
|
runtime( "Setting int attribute to non-int value" );
|
|
l->attrs[0].u.data = v1.val.i;
|
|
break;
|
|
case EAF_TYPE_AS_PATH:
|
|
if (v1.type != T_PATH)
|
|
runtime( "Setting path attribute to non-path value" );
|
|
l->attrs[0].u.ptr = v1.val.ad;
|
|
break;
|
|
case EAF_TYPE_INT_SET:
|
|
if (v1.type != T_CLIST)
|
|
runtime( "Setting int set attribute to non-clist value" );
|
|
l->attrs[0].u.ptr = v1.val.ad;
|
|
break;
|
|
case EAF_TYPE_UNDEF:
|
|
if (v1.type != T_VOID)
|
|
runtime( "Setting void attribute to non-void value" );
|
|
l->attrs[0].u.data = 0;
|
|
break;
|
|
default: bug("Unknown type in e,S");
|
|
}
|
|
|
|
if (!(what->aux & EAF_TEMP) && (!(f_flags & FF_FORCE_TMPATTR))) {
|
|
rta_cow();
|
|
l->next = f_rta_copy->eattrs;
|
|
f_rta_copy->eattrs = l;
|
|
} else {
|
|
l->next = (*f_tmp_attrs);
|
|
(*f_tmp_attrs) = l;
|
|
}
|
|
}
|
|
break;
|
|
case 'P':
|
|
res.type = T_INT;
|
|
res.val.i = (*f_rte)->pref;
|
|
break;
|
|
case P('P','S'):
|
|
ONEARG;
|
|
if (v1.type != T_INT)
|
|
runtime( "Can't set preference to non-integer" );
|
|
*f_rte = rte_cow(*f_rte);
|
|
(*f_rte)->pref = v1.val.i;
|
|
break;
|
|
case 'L': /* Get length of */
|
|
ONEARG;
|
|
res.type = T_INT;
|
|
switch(v1.type) {
|
|
case T_PREFIX: res.val.i = v1.val.px.len; break;
|
|
case T_PATH: res.val.i = as_path_getlen(v1.val.ad); break;
|
|
default: bug( "Length of what?" );
|
|
}
|
|
break;
|
|
case P('c','p'): /* Convert prefix to ... */
|
|
ONEARG;
|
|
if (v1.type != T_PREFIX)
|
|
runtime( "Prefix expected" );
|
|
res.type = what->aux;
|
|
switch(res.type) {
|
|
/* case T_INT: res.val.i = v1.val.px.len; break; Not needed any more */
|
|
case T_IP: res.val.px.ip = v1.val.px.ip; break;
|
|
default: bug( "Unknown prefix to conversion" );
|
|
}
|
|
break;
|
|
case 'r':
|
|
ONEARG;
|
|
res = v1;
|
|
res.type |= T_RETURN;
|
|
break;
|
|
case P('c','a'): /* CALL: this is special: if T_RETURN and returning some value, mask it out */
|
|
ONEARG;
|
|
res = interpret(what->a2.p);
|
|
if (res.type == T_RETURN)
|
|
return res;
|
|
res.type &= ~T_RETURN;
|
|
break;
|
|
case P('S','W'):
|
|
ONEARG;
|
|
{
|
|
struct f_tree *t = find_tree(what->a2.p, v1);
|
|
if (!t) {
|
|
v1.type = T_VOID;
|
|
t = find_tree(what->a2.p, v1);
|
|
if (!t) {
|
|
debug( "No else statement?\n");
|
|
break;
|
|
}
|
|
}
|
|
/* It is actually possible to have t->data NULL */
|
|
return interpret(t->data);
|
|
}
|
|
break;
|
|
case P('i','M'): /* IP.MASK(val) */
|
|
TWOARGS;
|
|
if (v2.type != T_INT)
|
|
runtime( "Integer expected");
|
|
if (v1.type != T_IP)
|
|
runtime( "You can mask only IP addresses" );
|
|
{
|
|
ip_addr mask = ipa_mkmask(v2.val.i);
|
|
res.type = T_IP;
|
|
res.val.px.ip = ipa_and(mask, v1.val.px.ip);
|
|
}
|
|
break;
|
|
|
|
case 'E': /* Create empty attribute */
|
|
res.type = what->aux;
|
|
res.val.ad = adata_empty(f_pool);
|
|
break;
|
|
case P('A','p'): /* Path prepend */
|
|
TWOARGS;
|
|
if (v1.type != T_PATH)
|
|
runtime("Can't prepend to non-path");
|
|
if (v2.type != T_INT)
|
|
runtime("Can't prepend non-integer");
|
|
|
|
res.type = T_PATH;
|
|
res.val.ad = as_path_prepend(f_pool, v1.val.ad, v2.val.i);
|
|
break;
|
|
|
|
case P('C','a'): /* Community list add or delete */
|
|
TWOARGS;
|
|
if (v1.type != T_CLIST)
|
|
runtime("Can't add/delete to non-clist");
|
|
if (v2.type != T_PAIR)
|
|
runtime("Can't add/delete non-pair");
|
|
|
|
res.type = T_CLIST;
|
|
switch (what->aux) {
|
|
case 'a': res.val.ad = int_set_add(f_pool, v1.val.ad, v2.val.i); break;
|
|
case 'd': res.val.ad = int_set_del(f_pool, v1.val.ad, v2.val.i); break;
|
|
default: bug("unknown Ca operation");
|
|
}
|
|
break;
|
|
|
|
default:
|
|
bug( "Unknown instruction %d (%c)", what->code, what->code & 0xff);
|
|
}
|
|
if (what->next)
|
|
return interpret(what->next);
|
|
return res;
|
|
}
|
|
|
|
#undef ARG
|
|
#define ARG(x,y) \
|
|
if (!i_same(f1->y, f2->y)) \
|
|
return 0;
|
|
|
|
#define ONEARG ARG(v1, a1.p)
|
|
#define TWOARGS ARG(v1, a1.p) \
|
|
ARG(v2, a2.p)
|
|
|
|
#define A2_SAME if (f1->a2.i != f2->a2.i) return 0;
|
|
|
|
/*
|
|
* i_same - function that does real comparing of instruction trees, you should call filter_same from outside
|
|
*/
|
|
int
|
|
i_same(struct f_inst *f1, struct f_inst *f2)
|
|
{
|
|
if ((!!f1) != (!!f2))
|
|
return 0;
|
|
if (!f1)
|
|
return 1;
|
|
if (f1->aux != f2->aux)
|
|
return 0;
|
|
if (f1->code != f2->code)
|
|
return 0;
|
|
if (f1 == f2) /* It looks strange, but it is possible with call rewriting trickery */
|
|
return 1;
|
|
|
|
switch(f1->code) {
|
|
case ',': /* fall through */
|
|
case '+':
|
|
case '-':
|
|
case '*':
|
|
case '/':
|
|
case '|':
|
|
case '&':
|
|
case P('!','='):
|
|
case P('=','='):
|
|
case '<':
|
|
case P('<','='): TWOARGS; break;
|
|
|
|
case '!': ONEARG; break;
|
|
case '~': TWOARGS; break;
|
|
case P('d','e'): ONEARG; break;
|
|
|
|
case 's':
|
|
ARG(v2, a2.p);
|
|
{
|
|
struct symbol *s1, *s2;
|
|
s1 = f1->a1.p;
|
|
s2 = f2->a1.p;
|
|
if (strcmp(s1->name, s2->name))
|
|
return 0;
|
|
if (s1->class != s2->class)
|
|
return 0;
|
|
}
|
|
break;
|
|
|
|
case 'c':
|
|
if (f1->aux & T_SET) {
|
|
if (!same_tree(f1->a2.p, f2->a2.p))
|
|
return 0;
|
|
break;
|
|
}
|
|
switch (f1->aux) {
|
|
case T_STRING:
|
|
if (strcmp(f1->a2.p, f2->a2.p))
|
|
return 0;
|
|
break;
|
|
default:
|
|
A2_SAME;
|
|
}
|
|
break;
|
|
case 'C':
|
|
if (val_compare(* (struct f_val *) f1->a1.p, * (struct f_val *) f2->a1.p))
|
|
return 0;
|
|
break;
|
|
case 'p': case 'L': ONEARG; break;
|
|
case '?': TWOARGS; break;
|
|
case '0': case 'E': break;
|
|
case P('p',','): ONEARG; A2_SAME; break;
|
|
case 'P':
|
|
case 'a': A2_SAME; break;
|
|
case P('e','a'): A2_SAME; break;
|
|
case P('P','S'):
|
|
case P('a','S'):
|
|
case P('e','S'): ONEARG; A2_SAME; break;
|
|
|
|
case 'r': ONEARG; break;
|
|
case P('c','p'): ONEARG; break;
|
|
case P('c','a'): /* Call rewriting trickery to avoid exponential behaviour */
|
|
ONEARG;
|
|
if (!i_same(f1->a2.p, f2->a2.p))
|
|
return 0;
|
|
f2->a2.p = f1->a2.p;
|
|
break;
|
|
case P('S','W'): ONEARG; if (!same_tree(f1->a2.p, f2->a2.p)) return 0; break;
|
|
case P('i','M'): TWOARGS; break;
|
|
case P('A','p'): TWOARGS; break;
|
|
case P('C','a'): TWOARGS; break;
|
|
default:
|
|
bug( "Unknown instruction %d in same (%c)", f1->code, f1->code & 0xff);
|
|
}
|
|
return i_same(f1->next, f2->next);
|
|
}
|
|
|
|
/**
|
|
* f_run - external entry point to filters
|
|
* @filter: pointer to filter to run
|
|
* @tmp_attrs: where to store newly generated temporary attributes
|
|
* @rte: pointer to pointer to &rte being filtered. When route is modified, this is changed with rte_cow().
|
|
* @tmp_pool: all filter allocations go from this pool
|
|
* @flags: flags
|
|
*/
|
|
int
|
|
f_run(struct filter *filter, struct rte **rte, struct ea_list **tmp_attrs, struct linpool *tmp_pool, int flags)
|
|
{
|
|
struct f_inst *inst;
|
|
struct f_val res;
|
|
DBG( "Running filter `%s'...", filter->name );
|
|
|
|
f_flags = flags;
|
|
f_tmp_attrs = tmp_attrs;
|
|
f_rte = rte;
|
|
f_rte_old = *rte;
|
|
f_rta_copy = NULL;
|
|
f_pool = tmp_pool;
|
|
inst = filter->root;
|
|
res = interpret(inst);
|
|
if (res.type != T_RETURN) {
|
|
log( L_ERR "Filter %s did not return accept nor reject. Make up your mind", filter->name);
|
|
return F_ERROR;
|
|
}
|
|
DBG( "done (%d)\n", res.val.i );
|
|
return res.val.i;
|
|
}
|
|
|
|
int
|
|
f_eval_int(struct f_inst *expr)
|
|
{
|
|
struct f_val res;
|
|
|
|
f_flags = 0;
|
|
f_tmp_attrs = NULL;
|
|
f_rte = NULL;
|
|
f_rte_old = NULL;
|
|
f_rta_copy = NULL;
|
|
f_pool = cfg_mem;
|
|
res = interpret(expr);
|
|
if (res.type != T_INT)
|
|
cf_error("Integer expression expected");
|
|
return res.val.i;
|
|
}
|
|
|
|
/**
|
|
* filter_same - compare two filters
|
|
* @new: first filter to be compared
|
|
* @old: second filter to be compared, notice that this filter is
|
|
* damaged while comparing.
|
|
*
|
|
* Returns 1 in case filters are same, otherwise 0. If there are
|
|
* underlying bugs, it will rather say 0 on same filters than say
|
|
* 1 on different.
|
|
*/
|
|
int
|
|
filter_same(struct filter *new, struct filter *old)
|
|
{
|
|
if (old == new) /* Handle FILTER_ACCEPT and FILTER_REJECT */
|
|
return 1;
|
|
if (old == FILTER_ACCEPT || old == FILTER_REJECT ||
|
|
new == FILTER_ACCEPT || new == FILTER_REJECT)
|
|
return 0;
|
|
return i_same(new->root, old->root);
|
|
}
|