Jerry/bird
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
bird/filter/filter.c
Ondrej Zajicek (work) 41b83e52f7 Filter: Fix minor bug in accessing bgp_path 
Not relevant for regular BGP paths, just for BGP paths added by filters
to e.g. static routes.
2018-10-25 11:23:15 +02:00

1857 lines
45 KiB
C
Raw Blame History

/*
* 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 "lib/net.h"
#include "lib/ip.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 CMP_ERROR 999
void (*bt_assert_hook)(int result, struct f_inst *assert);
static struct adata undef_adata; /* adata of length 0 used for undefined */
/* 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 == &undef_adata);
}
static struct adata *
adata_empty(struct linpool *pool, int l)
{
struct adata *res = lp_alloc(pool, sizeof(struct adata) + l);
res->length = l;
return res;
}
static void
pm_format(struct f_path_mask *p, buffer *buf)
{
buffer_puts(buf, "[= ");
while (p)
{
switch(p->kind)
{
case PM_ASN:
buffer_print(buf, "%u ", p->val);
break;
case PM_QUESTION:
buffer_puts(buf, "? ");
break;
case PM_ASTERISK:
buffer_puts(buf, "* ");
break;
case PM_ASN_RANGE:
buffer_print(buf, "%u..%u ", p->val, p->val2);
break;
case PM_ASN_EXPR:
ASSERT(0);
}
p = p->next;
}
buffer_puts(buf, "=]");
}
static inline int val_is_ip4(const struct f_val v)
{ return (v.type == T_IP) && ipa_is_ip4(v.val.ip); }
static inline int
lcomm_cmp(lcomm v1, lcomm v2)
{
if (v1.asn != v2.asn)
return (v1.asn > v2.asn) ? 1 : -1;
if (v1.ldp1 != v2.ldp1)
return (v1.ldp1 > v2.ldp1) ? 1 : -1;
if (v1.ldp2 != v2.ldp2)
return (v1.ldp2 > v2.ldp2) ? 1 : -1;
return 0;
}
/**
* val_compare - compare two values
* @v1: first value
* @v2: second value
*
* Compares two values and returns -1, 0, 1 on <, =, > or CMP_ERROR on
* error. Tree module relies on this giving consistent results so
* that it can be used for building balanced trees.
*/
int
val_compare(struct f_val v1, struct f_val v2)
{
if (v1.type != v2.type) {
if (v1.type == T_VOID) /* Hack for else */
return -1;
if (v2.type == T_VOID)
return 1;
/* IP->Quad implicit conversion */
if ((v1.type == T_QUAD) && val_is_ip4(v2))
return uint_cmp(v1.val.i, ipa_to_u32(v2.val.ip));
if (val_is_ip4(v1) && (v2.type == T_QUAD))
return uint_cmp(ipa_to_u32(v1.val.ip), v2.val.i);
debug( "Types do not match in val_compare\n" );
return CMP_ERROR;
}
switch (v1.type) {
case T_VOID:
return 0;
case T_ENUM:
case T_INT:
case T_BOOL:
case T_PAIR:
case T_QUAD:
return uint_cmp(v1.val.i, v2.val.i);
case T_EC:
case T_RD:
return u64_cmp(v1.val.ec, v2.val.ec);
case T_LC:
return lcomm_cmp(v1.val.lc, v2.val.lc);
case T_IP:
return ipa_compare(v1.val.ip, v2.val.ip);
case T_NET:
return net_compare(v1.val.net, v2.val.net);
case T_STRING:
return strcmp(v1.val.s, v2.val.s);
default:
return CMP_ERROR;
}
}
static int
pm_same(struct f_path_mask *m1, struct f_path_mask *m2)
{
while (m1 && m2)
{
if (m1->kind != m2->kind)
return 0;
if (m1->kind == PM_ASN_EXPR)
{
if (!i_same((struct f_inst *) m1->val, (struct f_inst *) m2->val))
return 0;
}
else
{
if ((m1->val != m2->val) || (m1->val2 != m2->val2))
return 0;
}
m1 = m1->next;
m2 = m2->next;
}
return !m1 && !m2;
}
/**
* val_same - compare two values
* @v1: first value
* @v2: second value
*
* Compares two values and returns 1 if they are same and 0 if not.
* Comparison of values of different types is valid and returns 0.
*/
int
val_same(struct f_val v1, struct f_val v2)
{
int rc;
rc = val_compare(v1, v2);
if (rc != CMP_ERROR)
return !rc;
if (v1.type != v2.type)
return 0;
switch (v1.type) {
case T_PATH_MASK:
return pm_same(v1.val.path_mask, v2.val.path_mask);
case T_PATH:
case T_CLIST:
case T_ECLIST:
case T_LCLIST:
return adata_same(v1.val.ad, v2.val.ad);
case T_SET:
return same_tree(v1.val.t, v2.val.t);
case T_PREFIX_SET:
return trie_same(v1.val.ti, v2.val.ti);
default:
bug("Invalid type in val_same(): %x", v1.type);
}
}
static int
clist_set_type(struct f_tree *set, struct f_val *v)
{
switch (set->from.type)
{
case T_PAIR:
v->type = T_PAIR;
return 1;
case T_QUAD:
v->type = T_QUAD;
return 1;
case T_IP:
if (val_is_ip4(set->from) && val_is_ip4(set->to))
{
v->type = T_QUAD;
return 1;
}
/* Fall through */
default:
v->type = T_VOID;
return 0;
}
}
static inline int
eclist_set_type(struct f_tree *set)
{ return set->from.type == T_EC; }
static inline int
lclist_set_type(struct f_tree *set)
{ return set->from.type == T_LC; }
static int
clist_match_set(struct adata *clist, struct f_tree *set)
{
if (!clist)
return 0;
struct f_val v;
if (!clist_set_type(set, &v))
return CMP_ERROR;
u32 *l = (u32 *) clist->data;
u32 *end = l + clist->length/4;
while (l < end) {
v.val.i = *l++;
if (find_tree(set, v))
return 1;
}
return 0;
}
static int
eclist_match_set(struct adata *list, struct f_tree *set)
{
if (!list)
return 0;
if (!eclist_set_type(set))
return CMP_ERROR;
struct f_val v;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
int i;
v.type = T_EC;
for (i = 0; i < len; i += 2) {
v.val.ec = ec_get(l, i);
if (find_tree(set, v))
return 1;
}
return 0;
}
static int
lclist_match_set(struct adata *list, struct f_tree *set)
{
if (!list)
return 0;
if (!lclist_set_type(set))
return CMP_ERROR;
struct f_val v;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
int i;
v.type = T_LC;
for (i = 0; i < len; i += 3) {
v.val.lc = lc_get(l, i);
if (find_tree(set, v))
return 1;
}
return 0;
}
static struct adata *
clist_filter(struct linpool *pool, struct adata *list, struct f_val set, int pos)
{
if (!list)
return NULL;
int tree = (set.type == T_SET); /* 1 -> set is T_SET, 0 -> set is T_CLIST */
struct f_val v;
if (tree)
clist_set_type(set.val.t, &v);
else
v.type = T_PAIR;
int len = int_set_get_size(list);
u32 *l = int_set_get_data(list);
u32 tmp[len];
u32 *k = tmp;
u32 *end = l + len;
while (l < end) {
v.val.i = *l++;
/* pos && member(val, set) || !pos && !member(val, set), member() depends on tree */
if ((tree ? !!find_tree(set.val.t, v) : int_set_contains(set.val.ad, v.val.i)) == pos)
*k++ = v.val.i;
}
uint nl = (k - tmp) * sizeof(u32);
if (nl == list->length)
return list;
struct adata *res = adata_empty(pool, nl);
memcpy(res->data, tmp, nl);
return res;
}
static struct adata *
eclist_filter(struct linpool *pool, struct adata *list, struct f_val set, int pos)
{
if (!list)
return NULL;
int tree = (set.type == T_SET); /* 1 -> set is T_SET, 0 -> set is T_CLIST */
struct f_val v;
int len = int_set_get_size(list);
u32 *l = int_set_get_data(list);
u32 tmp[len];
u32 *k = tmp;
int i;
v.type = T_EC;
for (i = 0; i < len; i += 2) {
v.val.ec = ec_get(l, i);
/* pos && member(val, set) || !pos && !member(val, set), member() depends on tree */
if ((tree ? !!find_tree(set.val.t, v) : ec_set_contains(set.val.ad, v.val.ec)) == pos) {
*k++ = l[i];
*k++ = l[i+1];
}
}
uint nl = (k - tmp) * sizeof(u32);
if (nl == list->length)
return list;
struct adata *res = adata_empty(pool, nl);
memcpy(res->data, tmp, nl);
return res;
}
static struct adata *
lclist_filter(struct linpool *pool, struct adata *list, struct f_val set, int pos)
{
if (!list)
return NULL;
int tree = (set.type == T_SET); /* 1 -> set is T_SET, 0 -> set is T_CLIST */
struct f_val v;
int len = int_set_get_size(list);
u32 *l = int_set_get_data(list);
u32 tmp[len];
u32 *k = tmp;
int i;
v.type = T_LC;
for (i = 0; i < len; i += 3) {
v.val.lc = lc_get(l, i);
/* pos && member(val, set) || !pos && !member(val, set), member() depends on tree */
if ((tree ? !!find_tree(set.val.t, v) : lc_set_contains(set.val.ad, v.val.lc)) == pos)
k = lc_copy(k, l+i);
}
uint nl = (k - tmp) * sizeof(u32);
if (nl == list->length)
return list;
struct adata *res = adata_empty(pool, nl);
memcpy(res->data, tmp, nl);
return res;
}
/**
* val_in_range - implement |~| operator
* @v1: element
* @v2: set
*
* Checks if @v1 is element (|~| operator) of @v2.
*/
static int
val_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_INT) && (v2.type == T_PATH))
return as_path_contains(v2.val.ad, v1.val.i, 1);
if (((v1.type == T_PAIR) || (v1.type == T_QUAD)) && (v2.type == T_CLIST))
return int_set_contains(v2.val.ad, v1.val.i);
/* IP->Quad implicit conversion */
if (val_is_ip4(v1) && (v2.type == T_CLIST))
return int_set_contains(v2.val.ad, ipa_to_u32(v1.val.ip));
if ((v1.type == T_EC) && (v2.type == T_ECLIST))
return ec_set_contains(v2.val.ad, v1.val.ec);
if ((v1.type == T_LC) && (v2.type == T_LCLIST))
return lc_set_contains(v2.val.ad, v1.val.lc);
if ((v1.type == T_STRING) && (v2.type == T_STRING))
return patmatch(v2.val.s, v1.val.s);
if ((v1.type == T_IP) && (v2.type == T_NET))
return ipa_in_netX(v1.val.ip, v2.val.net);
if ((v1.type == T_NET) && (v2.type == T_NET))
return net_in_netX(v1.val.net, v2.val.net);
if ((v1.type == T_NET) && (v2.type == T_PREFIX_SET))
return trie_match_net(v2.val.ti, v1.val.net);
if (v2.type != T_SET)
return CMP_ERROR;
/* With integrated Quad<->IP implicit conversion */
if ((v1.type == v2.val.t->from.type) ||
((v1.type == T_QUAD) && val_is_ip4(v2.val.t->from) && val_is_ip4(v2.val.t->to)))
return !!find_tree(v2.val.t, v1);
if (v1.type == T_CLIST)
return clist_match_set(v1.val.ad, v2.val.t);
if (v1.type == T_ECLIST)
return eclist_match_set(v1.val.ad, v2.val.t);
if (v1.type == T_LCLIST)
return lclist_match_set(v1.val.ad, v2.val.t);
if (v1.type == T_PATH)
return as_path_match_set(v1.val.ad, v2.val.t);
return CMP_ERROR;
}
/*
* val_format - format filter value
*/
void
val_format(struct f_val v, buffer *buf)
{
char buf2[1024];
switch (v.type)
{
case T_VOID: buffer_puts(buf, "(void)"); return;
case T_BOOL: buffer_puts(buf, v.val.i ? "TRUE" : "FALSE"); return;
case T_INT: buffer_print(buf, "%u", v.val.i); return;
case T_STRING: buffer_print(buf, "%s", v.val.s); return;
case T_IP: buffer_print(buf, "%I", v.val.ip); return;
case T_NET: buffer_print(buf, "%N", v.val.net); return;
case T_PAIR: buffer_print(buf, "(%u,%u)", v.val.i >> 16, v.val.i & 0xffff); return;
case T_QUAD: buffer_print(buf, "%R", v.val.i); return;
case T_EC: ec_format(buf2, v.val.ec); buffer_print(buf, "%s", buf2); return;
case T_LC: lc_format(buf2, v.val.lc); buffer_print(buf, "%s", buf2); return;
case T_RD: rd_format(v.val.ec, buf2, 1024); buffer_print(buf, "%s", buf2); return;
case T_PREFIX_SET: trie_format(v.val.ti, buf); return;
case T_SET: tree_format(v.val.t, buf); return;
case T_ENUM: buffer_print(buf, "(enum %x)%u", v.type, v.val.i); return;
case T_PATH: as_path_format(v.val.ad, buf2, 1000); buffer_print(buf, "(path %s)", buf2); return;
case T_CLIST: int_set_format(v.val.ad, 1, -1, buf2, 1000); buffer_print(buf, "(clist %s)", buf2); return;
case T_ECLIST: ec_set_format(v.val.ad, -1, buf2, 1000); buffer_print(buf, "(eclist %s)", buf2); return;
case T_LCLIST: lc_set_format(v.val.ad, -1, buf2, 1000); buffer_print(buf, "(lclist %s)", buf2); return;
case T_PATH_MASK: pm_format(v.val.path_mask, buf); return;
default: buffer_print(buf, "[unknown type %x]", v.type); return;
}
}
static struct rte **f_rte;
static struct rta *f_old_rta;
static struct ea_list **f_eattrs;
static struct linpool *f_pool;
static struct buffer f_buf;
static int f_flags;
static inline void f_cache_eattrs(void)
{
f_eattrs = &((*f_rte)->attrs->eattrs);
}
static inline void f_rte_cow(void)
{
if (!((*f_rte)->flags & REF_COW))
return;
*f_rte = rte_do_cow(*f_rte);
}
/*
* rta_cow - prepare rta for modification by filter
*/
static void
f_rta_cow(void)
{
if (!rta_is_cached((*f_rte)->attrs))
return;
/* Prepare to modify rte */
f_rte_cow();
/* Store old rta to free it later, it stores reference from rte_cow() */
f_old_rta = (*f_rte)->attrs;
/*
* Get shallow copy of rta. Fields eattrs and nexthops of rta are shared
* with f_old_rta (they will be copied when the cached rta will be obtained
* at the end of f_run()), also the lock of hostentry is inherited (we
* suppose hostentry is not changed by filters).
*/
(*f_rte)->attrs = rta_do_cow((*f_rte)->attrs, f_pool);
/* Re-cache the ea_list */
f_cache_eattrs();
}
static char *
val_format_str(struct f_val v) {
buffer b;
LOG_BUFFER_INIT(b);
val_format(v, &b);
return lp_strdup(f_pool, b.start);
}
static struct tbf rl_runtime_err = TBF_DEFAULT_LOG_LIMITS;
#define runtime(fmt, ...) do { \
if (!(f_flags & FF_SILENT)) \
log_rl(&rl_runtime_err, L_ERR "filters, line %d: " fmt, what->lineno, ##__VA_ARGS__); \
res.type = T_RETURN; \
res.val.i = F_ERROR; \
return res; \
} while(0)
#define ARG_ANY(n) INTERPRET(v##n, what->a##n.p)
#define ARG(n,t) ARG_ANY(n) \
if (v##n.type != t) \
runtime("Argument %d of instruction %s must be of type %02x, got %02x", \
n, f_instruction_name(what->fi_code), t, v##n.type);
#define INTERPRET(val, what_) \
val = interpret(what_); \
if (val.type & T_RETURN) \
return val;
#define ACCESS_RTE \
do { if (!f_rte) runtime("No route to access"); } while (0)
#define ACCESS_EATTRS \
do { if (!f_eattrs) f_cache_eattrs(); } while (0)
#define BITFIELD_MASK(what) \
(1u << (what->a2.i >> 24))
/**
* 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, v3, res = { .type = T_VOID }, *vp;
unsigned u1, u2;
int i;
u32 as;
for ( ; what; what = what->next) {
res.type = T_VOID;
switch(what->fi_code) {
/* Binary operators */
case FI_ADD:
ARG(1,T_INT);
ARG(2,T_INT);
res.type = T_INT;
res.val.i = v1.val.i + v2.val.i;
break;
case FI_SUBTRACT:
ARG(1,T_INT);
ARG(2,T_INT);
res.type = T_INT;
res.val.i = v1.val.i - v2.val.i;
break;
case FI_MULTIPLY:
ARG(1,T_INT);
ARG(2,T_INT);
res.type = T_INT;
res.val.i = v1.val.i * v2.val.i;
break;
case FI_DIVIDE:
ARG(1,T_INT);
ARG(2,T_INT);
res.type = 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 FI_AND:
case FI_OR:
ARG(1,T_BOOL);
if (v1.val.i == (what->fi_code == FI_OR)) {
res.type = T_BOOL;
res.val.i = v1.val.i;
} else {
ARG(2,T_BOOL);
res = v2;
}
break;
case FI_PAIR_CONSTRUCT:
ARG(1,T_INT);
ARG(2,T_INT);
u1 = v1.val.i;
u2 = v2.val.i;
if ((u1 > 0xFFFF) || (u2 > 0xFFFF))
runtime( "Can't operate with value out of bounds in pair constructor" );
res.val.i = (u1 << 16) | u2;
res.type = T_PAIR;
break;
case FI_EC_CONSTRUCT:
{
ARG_ANY(1);
ARG(2, T_INT);
int check, ipv4_used;
u32 key, val;
if (v1.type == T_INT) {
ipv4_used = 0; key = v1.val.i;
}
else if (v1.type == T_QUAD) {
ipv4_used = 1; key = v1.val.i;
}
/* IP->Quad implicit conversion */
else if (val_is_ip4(v1)) {
ipv4_used = 1; key = ipa_to_u32(v1.val.ip);
}
else
runtime("Can't operate with key of non-integer/IPv4 type in EC constructor");
val = v2.val.i;
/* XXXX */
res.type = T_EC;
if (what->aux == EC_GENERIC) {
check = 0; res.val.ec = ec_generic(key, val);
}
else if (ipv4_used) {
check = 1; res.val.ec = ec_ip4(what->aux, key, val);
}
else if (key < 0x10000) {
check = 0; res.val.ec = ec_as2(what->aux, key, val);
}
else {
check = 1; res.val.ec = ec_as4(what->aux, key, val);
}
if (check && (val > 0xFFFF))
runtime("Can't operate with value out of bounds in EC constructor");
break;
}
case FI_LC_CONSTRUCT:
{
ARG(1, T_INT);
ARG(2, T_INT);
ARG(3, T_INT);
res.type = T_LC;
res.val.lc = (lcomm) { v1.val.i, v2.val.i, v3.val.i };
break;
}
case FI_PATHMASK_CONSTRUCT:
{
struct f_path_mask *tt = what->a1.p, *vbegin, **vv = &vbegin;
while (tt) {
*vv = lp_alloc(f_pool, sizeof(struct f_path_mask));
if (tt->kind == PM_ASN_EXPR) {
struct f_val res;
INTERPRET(res, (struct f_inst *) tt->val);
(*vv)->kind = PM_ASN;
if (res.type != T_INT) {
runtime( "Error resolving path mask template: value not an integer" );
return (struct f_val) { .type = T_VOID };
}
(*vv)->val = res.val.i;
} else {
**vv = *tt;
}
tt = tt->next;
vv = &((*vv)->next);
}
res = (struct f_val) { .type = T_PATH_MASK, .val.path_mask = vbegin };
break;
}
/* Relational operators */
#define COMPARE(x) \
ARG_ANY(1); \
ARG_ANY(2); \
i = val_compare(v1, v2); \
if (i==CMP_ERROR) \
runtime( "Can't compare values of incompatible types" ); \
res.type = T_BOOL; \
res.val.i = (x); \
break;
#define SAME(x) \
ARG_ANY(1); \
ARG_ANY(2); \
i = val_same(v1, v2); \
res.type = T_BOOL; \
res.val.i = (x); \
break;
case FI_NEQ: SAME(!i);
case FI_EQ: SAME(i);
case FI_LT: COMPARE(i==-1);
case FI_LTE: COMPARE(i!=1);
case FI_NOT:
ARG(1,T_BOOL);
res = v1;
res.val.i = !res.val.i;
break;
case FI_MATCH:
ARG_ANY(1);
ARG_ANY(2);
res.type = T_BOOL;
res.val.i = val_in_range(v1, v2);
if (res.val.i == CMP_ERROR)
runtime( "~ applied on unknown type pair" );
res.val.i = !!res.val.i;
break;
case FI_NOT_MATCH:
ARG_ANY(1);
ARG_ANY(2);
res.type = T_BOOL;
res.val.i = val_in_range(v1, v2);
if (res.val.i == CMP_ERROR)
runtime( "!~ applied on unknown type pair" );
res.val.i = !res.val.i;
break;
case FI_DEFINED:
ARG_ANY(1);
res.type = T_BOOL;
res.val.i = (v1.type != T_VOID) && !undef_value(v1);
break;
case FI_TYPE:
ARG_ANY(1); /* There may be more types supporting this operation */
switch (v1.type)
{
case T_NET:
res.type = T_ENUM_NETTYPE;
res.val.i = v1.val.net->type;
break;
default:
runtime( "Can't determine type of this item" );
}
break;
case FI_IS_V4:
ARG(1, T_IP);
res.type = T_BOOL;
res.val.i = ipa_is_ip4(v1.val.ip);
break;
/* Set to indirect value, a1 = variable, a2 = value */
case FI_SET:
ARG_ANY(2);
sym = what->a1.p;
vp = sym->def;
if ((sym->class != (SYM_VARIABLE | v2.type)) && (v2.type != T_VOID))
{
/* IP->Quad implicit conversion */
if ((sym->class == (SYM_VARIABLE | T_QUAD)) && val_is_ip4(v2))
{
vp->type = T_QUAD;
vp->val.i = ipa_to_u32(v2.val.ip);
break;
}
runtime( "Assigning to variable of incompatible type" );
}
*vp = v2;
break;
/* some constants have value in a2, some in *a1.p, strange. */
case FI_CONSTANT: /* integer (or simple type) constant, string, set, or prefix_set */
res.type = what->aux;
if (res.type == T_PREFIX_SET)
res.val.ti = what->a2.p;
else if (res.type == T_SET)
res.val.t = what->a2.p;
else if (res.type == T_STRING)
res.val.s = what->a2.p;
else
res.val.i = what->a2.i;
break;
case FI_VARIABLE:
case FI_CONSTANT_INDIRECT:
res = * ((struct f_val *) what->a1.p);
break;
case FI_PRINT:
ARG_ANY(1);
val_format(v1, &f_buf);
break;
case FI_CONDITION: /* ? has really strange error value, so we can implement if ... else nicely :-) */
ARG(1, T_BOOL);
if (v1.val.i) {
ARG_ANY(2);
res.val.i = 0;
} else
res.val.i = 1;
res.type = T_BOOL;
break;
case FI_NOP:
debug( "No operation\n" );
break;
case FI_PRINT_AND_DIE:
ARG_ANY(1);
if ((what->a2.i == F_NOP || (what->a2.i != F_NONL && what->a1.p)) &&
!(f_flags & FF_SILENT))
log_commit(*L_INFO, &f_buf);
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 FI_RTA_GET: /* rta access */
{
ACCESS_RTE;
struct rta *rta = (*f_rte)->attrs;
res.type = what->aux;
switch (what->a2.i)
{
case SA_FROM: res.val.ip = rta->from; break;
case SA_GW: res.val.ip = rta->nh.gw; break;
case SA_NET: res.val.net = (*f_rte)->net->n.addr; break;
case SA_PROTO: res.val.s = rta->src->proto->name; break;
case SA_SOURCE: res.val.i = rta->source; break;
case SA_SCOPE: res.val.i = rta->scope; break;
case SA_DEST: res.val.i = rta->dest; break;
case SA_IFNAME: res.val.s = rta->nh.iface ? rta->nh.iface->name : ""; break;
case SA_IFINDEX: res.val.i = rta->nh.iface ? rta->nh.iface->index : 0; break;
default:
bug("Invalid static attribute access (%x)", res.type);
}
}
break;
case FI_RTA_SET:
ACCESS_RTE;
ARG_ANY(1);
if (what->aux != v1.type)
runtime( "Attempt to set static attribute to incompatible type" );
f_rta_cow();
{
struct rta *rta = (*f_rte)->attrs;
switch (what->a2.i)
{
case SA_FROM:
rta->from = v1.val.ip;
break;
case SA_GW:
{
ip_addr ip = v1.val.ip;
neighbor *n = neigh_find(rta->src->proto, ip, NULL, 0);
if (!n || (n->scope == SCOPE_HOST))
runtime( "Invalid gw address" );
rta->dest = RTD_UNICAST;
rta->nh.gw = ip;
rta->nh.iface = n->iface;
rta->nh.next = NULL;
rta->hostentry = NULL;
}
break;
case SA_SCOPE:
rta->scope = v1.val.i;
break;
case SA_DEST:
i = v1.val.i;
if ((i != RTD_BLACKHOLE) && (i != RTD_UNREACHABLE) && (i != RTD_PROHIBIT))
runtime( "Destination can be changed only to blackhole, unreachable or prohibit" );
rta->dest = i;
rta->nh.gw = IPA_NONE;
rta->nh.iface = NULL;
rta->nh.next = NULL;
rta->hostentry = NULL;
break;
default:
bug("Invalid static attribute access (%x)", res.type);
}
}
break;
case FI_EA_GET: /* Access to extended attributes */
ACCESS_RTE;
ACCESS_EATTRS;
{
u16 code = what->a2.i;
int f_type = what->aux >> 8;
eattr *e = ea_find(*f_eattrs, code);
if (!e) {
/* A special case: undefined as_path looks like empty as_path */
if ((what->aux & EAF_TYPE_MASK) == EAF_TYPE_AS_PATH) {
res.type = T_PATH;
res.val.ad = &undef_adata;
break;
}
/* The same special case for int_set */
if ((what->aux & EAF_TYPE_MASK) == EAF_TYPE_INT_SET) {
res.type = T_CLIST;
res.val.ad = &undef_adata;
break;
}
/* The same special case for ec_set */
if ((what->aux & EAF_TYPE_MASK) == EAF_TYPE_EC_SET) {
res.type = T_ECLIST;
res.val.ad = &undef_adata;
break;
}
/* The same special case for lc_set */
if ((what->aux & EAF_TYPE_MASK) == EAF_TYPE_LC_SET) {
res.type = T_LCLIST;
res.val.ad = &undef_adata;
break;
}
/* Undefined value */
res.type = T_VOID;
break;
}
switch (what->aux & EAF_TYPE_MASK) {
case EAF_TYPE_INT:
res.type = f_type;
res.val.i = e->u.data;
break;
case EAF_TYPE_ROUTER_ID:
res.type = T_QUAD;
res.val.i = e->u.data;
break;
case EAF_TYPE_OPAQUE:
res.type = T_ENUM_EMPTY;
res.val.i = 0;
break;
case EAF_TYPE_IP_ADDRESS:
res.type = T_IP;
struct adata * ad = e->u.ptr;
res.val.ip = * (ip_addr *) ad->data;
break;
case EAF_TYPE_AS_PATH:
res.type = T_PATH;
res.val.ad = e->u.ptr;
break;
case EAF_TYPE_BITFIELD:
res.type = T_BOOL;
res.val.i = !!(e->u.data & BITFIELD_MASK(what));
break;
case EAF_TYPE_INT_SET:
res.type = T_CLIST;
res.val.ad = e->u.ptr;
break;
case EAF_TYPE_EC_SET:
res.type = T_ECLIST;
res.val.ad = e->u.ptr;
break;
case EAF_TYPE_LC_SET:
res.type = T_LCLIST;
res.val.ad = e->u.ptr;
break;
case EAF_TYPE_UNDEF:
res.type = T_VOID;
break;
default:
bug("Unknown type in e,a");
}
}
break;
case FI_EA_SET:
ACCESS_RTE;
ACCESS_EATTRS;
ARG_ANY(1);
{
struct ea_list *l = lp_alloc(f_pool, sizeof(struct ea_list) + sizeof(eattr));
u16 code = what->a2.i;
int f_type = what->aux >> 8;
l->next = NULL;
l->flags = EALF_SORTED;
l->count = 1;
l->attrs[0].id = code;
l->attrs[0].flags = 0;
l->attrs[0].type = (what->aux & 0xff) | EAF_ORIGINATED | EAF_FRESH;
switch (what->aux & EAF_TYPE_MASK) {
case EAF_TYPE_INT:
if (v1.type != f_type)
runtime( "Setting int attribute to non-int value" );
l->attrs[0].u.data = v1.val.i;
break;
case EAF_TYPE_ROUTER_ID:
/* IP->Quad implicit conversion */
if (val_is_ip4(v1)) {
l->attrs[0].u.data = ipa_to_u32(v1.val.ip);
break;
}
/* T_INT for backward compatibility */
if ((v1.type != T_QUAD) && (v1.type != T_INT))
runtime( "Setting quad attribute to non-quad value" );
l->attrs[0].u.data = v1.val.i;
break;
case EAF_TYPE_OPAQUE:
runtime( "Setting opaque attribute is not allowed" );
break;
case EAF_TYPE_IP_ADDRESS:
if (v1.type != T_IP)
runtime( "Setting ip attribute to non-ip value" );
int len = sizeof(ip_addr);
struct adata *ad = lp_alloc(f_pool, sizeof(struct adata) + len);
ad->length = len;
(* (ip_addr *) ad->data) = v1.val.ip;
l->attrs[0].u.ptr = ad;
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_BITFIELD:
if (v1.type != T_BOOL)
runtime( "Setting bit in bitfield attribute to non-bool value" );
{
/* First, we have to find the old value */
eattr *e = ea_find(*f_eattrs, code);
u32 data = e ? e->u.data : 0;
if (v1.val.i)
l->attrs[0].u.data = data | BITFIELD_MASK(what);
else
l->attrs[0].u.data = data & ~BITFIELD_MASK(what);;
}
break;
case EAF_TYPE_INT_SET:
if (v1.type != T_CLIST)
runtime( "Setting clist attribute to non-clist value" );
l->attrs[0].u.ptr = v1.val.ad;
break;
case EAF_TYPE_EC_SET:
if (v1.type != T_ECLIST)
runtime( "Setting eclist attribute to non-eclist value" );
l->attrs[0].u.ptr = v1.val.ad;
break;
case EAF_TYPE_LC_SET:
if (v1.type != T_LCLIST)
runtime( "Setting lclist attribute to non-lclist 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");
}
f_rta_cow();
l->next = *f_eattrs;
*f_eattrs = l;
}
break;
case FI_PREF_GET:
ACCESS_RTE;
res.type = T_INT;
res.val.i = (*f_rte)->pref;
break;
case FI_PREF_SET:
ACCESS_RTE;
ARG(1,T_INT);
if (v1.val.i > 0xFFFF)
runtime( "Setting preference value out of bounds" );
f_rte_cow();
(*f_rte)->pref = v1.val.i;
break;
case FI_LENGTH: /* Get length of */
ARG_ANY(1);
res.type = T_INT;
switch(v1.type) {
case T_NET: res.val.i = net_pxlen(v1.val.net); break;
case T_PATH: res.val.i = as_path_getlen(v1.val.ad); break;
case T_CLIST: res.val.i = int_set_get_size(v1.val.ad); break;
case T_ECLIST: res.val.i = ec_set_get_size(v1.val.ad); break;
case T_LCLIST: res.val.i = lc_set_get_size(v1.val.ad); break;
default: runtime( "Prefix, path, clist or eclist expected" );
}
break;
case FI_SADR_SRC: /* Get SADR src prefix */
ARG(1, T_NET);
if (!net_is_sadr(v1.val.net))
runtime( "SADR expected" );
{
net_addr_ip6_sadr *net = (void *) v1.val.net;
net_addr *src = lp_alloc(f_pool, sizeof(net_addr_ip6));
net_fill_ip6(src, net->src_prefix, net->src_pxlen);
res.type = T_NET;
res.val.net = src;
}
break;
case FI_ROA_MAXLEN: /* Get ROA max prefix length */
ARG(1, T_NET);
if (!net_is_roa(v1.val.net))
runtime( "ROA expected" );
res.type = T_INT;
res.val.i = (v1.val.net->type == NET_ROA4) ?
((net_addr_roa4 *) v1.val.net)->max_pxlen :
((net_addr_roa6 *) v1.val.net)->max_pxlen;
break;
case FI_ROA_ASN: /* Get ROA ASN */
ARG(1, T_NET);
if (!net_is_roa(v1.val.net))
runtime( "ROA expected" );
res.type = T_INT;
res.val.i = (v1.val.net->type == NET_ROA4) ?
((net_addr_roa4 *) v1.val.net)->asn :
((net_addr_roa6 *) v1.val.net)->asn;
break;
case FI_IP: /* Convert prefix to ... */
ARG(1, T_NET);
res.type = T_IP;
res.val.ip = net_prefix(v1.val.net);
break;
case FI_ROUTE_DISTINGUISHER:
ARG(1, T_NET);
res.type = T_IP;
if (!net_is_vpn(v1.val.net))
runtime( "VPN address expected" );
res.type = T_RD;
res.val.ec = net_rd(v1.val.net);
break;
case FI_AS_PATH_FIRST: /* Get first ASN from AS PATH */
ARG(1, T_PATH);
as = 0;
as_path_get_first(v1.val.ad, &as);
res.type = T_INT;
res.val.i = as;
break;
case FI_AS_PATH_LAST: /* Get last ASN from AS PATH */
ARG(1, T_PATH);
as = 0;
as_path_get_last(v1.val.ad, &as);
res.type = T_INT;
res.val.i = as;
break;
case FI_AS_PATH_LAST_NAG: /* Get last ASN from non-aggregated part of AS PATH */
ARG(1, T_PATH);
res.type = T_INT;
res.val.i = as_path_get_last_nonaggregated(v1.val.ad);
break;
case FI_RETURN:
ARG_ANY(1);
res = v1;
res.type |= T_RETURN;
return res;
case FI_CALL: /* CALL: this is special: if T_RETURN and returning some value, mask it out */
ARG_ANY(1);
res = interpret(what->a2.p);
if (res.type == T_RETURN)
return res;
res.type &= ~T_RETURN;
break;
case FI_CLEAR_LOCAL_VARS: /* Clear local variables */
for (sym = what->a1.p; sym != NULL; sym = sym->aux2)
((struct f_val *) sym->def)->type = T_VOID;
break;
case FI_SWITCH:
ARG_ANY(1);
{
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 */
INTERPRET(res, t->data);
}
break;
case FI_IP_MASK: /* IP.MASK(val) */
ARG(1, T_IP);
ARG(2, T_INT);
res.type = T_IP;
res.val.ip = ipa_is_ip4(v1.val.ip) ?
ipa_from_ip4(ip4_and(ipa_to_ip4(v1.val.ip), ip4_mkmask(v2.val.i))) :
ipa_from_ip6(ip6_and(ipa_to_ip6(v1.val.ip), ip6_mkmask(v2.val.i)));
break;
case FI_EMPTY: /* Create empty attribute */
res.type = what->aux;
res.val.ad = adata_empty(f_pool, 0);
break;
case FI_PATH_PREPEND: /* Path prepend */
ARG(1, T_PATH);
ARG(2, T_INT);
res.type = T_PATH;
res.val.ad = as_path_prepend(f_pool, v1.val.ad, v2.val.i);
break;
case FI_CLIST_ADD_DEL: /* (Extended) Community list add or delete */
ARG_ANY(1);
ARG_ANY(2);
if (v1.type == T_PATH)
{
struct f_tree *set = NULL;
u32 key = 0;
int pos;
if (v2.type == T_INT)
key = v2.val.i;
else if ((v2.type == T_SET) && (v2.val.t->from.type == T_INT))
set = v2.val.t;
else
runtime("Can't delete non-integer (set)");
switch (what->aux)
{
case 'a': runtime("Can't add to path");
case 'd': pos = 0; break;
case 'f': pos = 1; break;
default: bug("unknown Ca operation");
}
if (pos && !set)
runtime("Can't filter integer");
res.type = T_PATH;
res.val.ad = as_path_filter(f_pool, v1.val.ad, set, key, pos);
}
else if (v1.type == T_CLIST)
{
/* Community (or cluster) list */
struct f_val dummy;
int arg_set = 0;
uint n = 0;
if ((v2.type == T_PAIR) || (v2.type == T_QUAD))
n = v2.val.i;
/* IP->Quad implicit conversion */
else if (val_is_ip4(v2))
n = ipa_to_u32(v2.val.ip);
else if ((v2.type == T_SET) && clist_set_type(v2.val.t, &dummy))
arg_set = 1;
else if (v2.type == T_CLIST)
arg_set = 2;
else
runtime("Can't add/delete non-pair");
res.type = T_CLIST;
switch (what->aux)
{
case 'a':
if (arg_set == 1)
runtime("Can't add set");
else if (!arg_set)
res.val.ad = int_set_add(f_pool, v1.val.ad, n);
else
res.val.ad = int_set_union(f_pool, v1.val.ad, v2.val.ad);
break;
case 'd':
if (!arg_set)
res.val.ad = int_set_del(f_pool, v1.val.ad, n);
else
res.val.ad = clist_filter(f_pool, v1.val.ad, v2, 0);
break;
case 'f':
if (!arg_set)
runtime("Can't filter pair");
res.val.ad = clist_filter(f_pool, v1.val.ad, v2, 1);
break;
default:
bug("unknown Ca operation");
}
}
else if (v1.type == T_ECLIST)
{
/* Extended community list */
int arg_set = 0;
/* v2.val is either EC or EC-set */
if ((v2.type == T_SET) && eclist_set_type(v2.val.t))
arg_set = 1;
else if (v2.type == T_ECLIST)
arg_set = 2;
else if (v2.type != T_EC)
runtime("Can't add/delete non-ec");
res.type = T_ECLIST;
switch (what->aux)
{
case 'a':
if (arg_set == 1)
runtime("Can't add set");
else if (!arg_set)
res.val.ad = ec_set_add(f_pool, v1.val.ad, v2.val.ec);
else
res.val.ad = ec_set_union(f_pool, v1.val.ad, v2.val.ad);
break;
case 'd':
if (!arg_set)
res.val.ad = ec_set_del(f_pool, v1.val.ad, v2.val.ec);
else
res.val.ad = eclist_filter(f_pool, v1.val.ad, v2, 0);
break;
case 'f':
if (!arg_set)
runtime("Can't filter ec");
res.val.ad = eclist_filter(f_pool, v1.val.ad, v2, 1);
break;
default:
bug("unknown Ca operation");
}
}
else if (v1.type == T_LCLIST)
{
/* Large community list */
int arg_set = 0;
/* v2.val is either LC or LC-set */
if ((v2.type == T_SET) && lclist_set_type(v2.val.t))
arg_set = 1;
else if (v2.type == T_LCLIST)
arg_set = 2;
else if (v2.type != T_LC)
runtime("Can't add/delete non-lc");
res.type = T_LCLIST;
switch (what->aux)
{
case 'a':
if (arg_set == 1)
runtime("Can't add set");
else if (!arg_set)
res.val.ad = lc_set_add(f_pool, v1.val.ad, v2.val.lc);
else
res.val.ad = lc_set_union(f_pool, v1.val.ad, v2.val.ad);
break;
case 'd':
if (!arg_set)
res.val.ad = lc_set_del(f_pool, v1.val.ad, v2.val.lc);
else
res.val.ad = lclist_filter(f_pool, v1.val.ad, v2, 0);
break;
case 'f':
if (!arg_set)
runtime("Can't filter lc");
res.val.ad = lclist_filter(f_pool, v1.val.ad, v2, 1);
break;
default:
bug("unknown Ca operation");
}
}
else
runtime("Can't add/delete to non-[e|l]clist");
break;
case FI_ROA_CHECK: /* ROA Check */
if (what->arg1)
{
ARG(1, T_NET);
ARG(2, T_INT);
as = v2.val.i;
}
else
{
ACCESS_RTE;
ACCESS_EATTRS;
v1.val.net = (*f_rte)->net->n.addr;
/* We ignore temporary attributes, probably not a problem here */
/* 0x02 is a value of BA_AS_PATH, we don't want to include BGP headers */
eattr *e = ea_find(*f_eattrs, EA_CODE(PROTOCOL_BGP, 0x02));
if (!e || ((e->type & EAF_TYPE_MASK) != EAF_TYPE_AS_PATH))
runtime("Missing AS_PATH attribute");
as_path_get_last(e->u.ptr, &as);
}
struct rtable *table = ((struct f_inst_roa_check *) what)->rtc->table;
if (!table)
runtime("Missing ROA table");
if (table->addr_type != NET_ROA4 && table->addr_type != NET_ROA6)
runtime("Table type must be either ROA4 or ROA6");
res.type = T_ENUM_ROA;
if (table->addr_type != (v1.val.net->type == NET_IP4 ? NET_ROA4 : NET_ROA6))
res.val.i = ROA_UNKNOWN; /* Prefix and table type mismatch */
else
res.val.i = net_roa_check(table, v1.val.net, as);
break;
case FI_FORMAT: /* Format */
ARG_ANY(1);
res.type = T_STRING;
res.val.s = val_format_str(v1);
break;
case FI_ASSERT: /* Birdtest Assert */
ARG(1, T_BOOL);
res.type = v1.type;
res.val = v1.val;
CALL(bt_assert_hook, res.val.i, what);
break;
default:
bug( "Unknown instruction %d (%c)", what->fi_code, what->fi_code & 0xff);
}}
return res;
}
#undef ARG
#undef ARG_ANY
#define ARG(n) \
if (!i_same(f1->a##n.p, f2->a##n.p)) \
return 0;
#define ONEARG ARG(1);
#define TWOARGS ONEARG; ARG(2);
#define THREEARGS TWOARGS; ARG(3);
#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->fi_code != f2->fi_code)
return 0;
if (f1 == f2) /* It looks strange, but it is possible with call rewriting trickery */
return 1;
switch(f1->fi_code) {
case FI_ADD: /* fall through */
case FI_SUBTRACT:
case FI_MULTIPLY:
case FI_DIVIDE:
case FI_OR:
case FI_AND:
case FI_PAIR_CONSTRUCT:
case FI_EC_CONSTRUCT:
case FI_NEQ:
case FI_EQ:
case FI_LT:
case FI_LTE: TWOARGS; break;
case FI_PATHMASK_CONSTRUCT: if (!pm_same(f1->a1.p, f2->a1.p)) return 0; break;
case FI_NOT: ONEARG; break;
case FI_NOT_MATCH:
case FI_MATCH: TWOARGS; break;
case FI_DEFINED: ONEARG; break;
case FI_TYPE: ONEARG; break;
case FI_LC_CONSTRUCT:
THREEARGS;
break;
case FI_SET:
ARG(2);
{
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 FI_CONSTANT:
switch (f1->aux) {
case T_PREFIX_SET:
if (!trie_same(f1->a2.p, f2->a2.p))
return 0;
break;
case T_SET:
if (!same_tree(f1->a2.p, f2->a2.p))
return 0;
break;
case T_STRING:
if (strcmp(f1->a2.p, f2->a2.p))
return 0;
break;
default:
A2_SAME;
}
break;
case FI_CONSTANT_INDIRECT:
if (!val_same(* (struct f_val *) f1->a1.p, * (struct f_val *) f2->a1.p))
return 0;
break;
case FI_VARIABLE:
if (strcmp((char *) f1->a2.p, (char *) f2->a2.p))
return 0;
break;
case FI_PRINT: case FI_LENGTH: ONEARG; break;
case FI_CONDITION: TWOARGS; break;
case FI_NOP: case FI_EMPTY: break;
case FI_PRINT_AND_DIE: ONEARG; A2_SAME; break;
case FI_PREF_GET:
case FI_RTA_GET: A2_SAME; break;
case FI_EA_GET: A2_SAME; break;
case FI_PREF_SET:
case FI_RTA_SET:
case FI_EA_SET: ONEARG; A2_SAME; break;
case FI_RETURN: ONEARG; break;
case FI_ROA_MAXLEN: ONEARG; break;
case FI_ROA_ASN: ONEARG; break;
case FI_SADR_SRC: ONEARG; break;
case FI_IP: ONEARG; break;
case FI_IS_V4: ONEARG; break;
case FI_ROUTE_DISTINGUISHER: ONEARG; break;
case FI_CALL: /* 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 FI_CLEAR_LOCAL_VARS: break; /* internal instruction */
case FI_SWITCH: ONEARG; if (!same_tree(f1->a2.p, f2->a2.p)) return 0; break;
case FI_IP_MASK: TWOARGS; break;
case FI_PATH_PREPEND: TWOARGS; break;
case FI_CLIST_ADD_DEL: TWOARGS; break;
case FI_AS_PATH_FIRST:
case FI_AS_PATH_LAST:
case FI_AS_PATH_LAST_NAG: ONEARG; break;
case FI_ROA_CHECK:
TWOARGS;
/* Does not really make sense - ROA check results may change anyway */
if (strcmp(((struct f_inst_roa_check *) f1)->rtc->name,
((struct f_inst_roa_check *) f2)->rtc->name))
return 0;
break;
case FI_FORMAT: ONEARG; break;
case FI_ASSERT: ONEARG; break;
default:
bug( "Unknown instruction %d in same (%c)", f1->fi_code, f1->fi_code & 0xff);
}
return i_same(f1->next, f2->next);
}
/**
* f_run - run a filter for a route
* @filter: filter to run
* @rte: route being filtered, may be modified
* @tmp_pool: all filter allocations go from this pool
* @flags: flags
*
* If filter needs to modify the route, there are several
* posibilities. @rte might be read-only (with REF_COW flag), in that
* case rw copy is obtained by rte_cow() and @rte is replaced. If
* @rte is originally rw, it may be directly modified (and it is never
* copied).
*
* The returned rte may reuse the (possibly cached, cloned) rta, or
* (if rta was modificied) contains a modified uncached rta, which
* uses parts allocated from @tmp_pool and parts shared from original
* rta. There is one exception - if @rte is rw but contains a cached
* rta and that is modified, rta in returned rte is also cached.
*
* Ownership of cached rtas is consistent with rte, i.e.
* if a new rte is returned, it has its own clone of cached rta
* (and cached rta of read-only source rte is intact), if rte is
* modified in place, old cached rta is possibly freed.
*/
int
f_run(struct filter *filter, struct rte **rte, struct linpool *tmp_pool, int flags)
{
if (filter == FILTER_ACCEPT)
return F_ACCEPT;
if (filter == FILTER_REJECT)
return F_REJECT;
int rte_cow = ((*rte)->flags & REF_COW);
DBG( "Running filter `%s'...", filter->name );
f_rte = rte;
f_eattrs = NULL;
f_old_rta = NULL;
f_pool = tmp_pool;
f_flags = flags;
LOG_BUFFER_INIT(f_buf);
struct f_val res = interpret(filter->root);
if (f_old_rta) {
/*
* Cached rta was modified and f_rte contains now an uncached one,
* sharing some part with the cached one. The cached rta should
* be freed (if rte was originally COW, f_old_rta is a clone
* obtained during rte_cow()).
*
* This also implements the exception mentioned in f_run()
* description. The reason for this is that rta reuses parts of
* f_old_rta, and these may be freed during rta_free(f_old_rta).
* This is not the problem if rte was COW, because original rte
* also holds the same rta.
*/
if (!rte_cow)
(*f_rte)->attrs = rta_lookup((*f_rte)->attrs);
rta_free(f_old_rta);
}
if (res.type != T_RETURN) {
if (!(f_flags & FF_SILENT))
log_rl(&rl_runtime_err, L_ERR "Filter %s did not return accept nor reject. Make up your mind", filter->name);
return F_ERROR;
}
DBG( "done (%u)\n", res.val.i );
return res.val.i;
}
/* TODO: perhaps we could integrate f_eval(), f_eval_rte() and f_run() */
struct f_val
f_eval_rte(struct f_inst *expr, struct rte **rte, struct linpool *tmp_pool)
{
f_rte = rte;
f_eattrs = NULL;
f_old_rta = NULL;
f_pool = tmp_pool;
f_flags = 0;
LOG_BUFFER_INIT(f_buf);
/* Note that in this function we assume that rte->attrs is private / uncached */
struct f_val res = interpret(expr);
return res;
}
struct f_val
f_eval(struct f_inst *expr, struct linpool *tmp_pool)
{
f_flags = 0;
f_eattrs = NULL;
f_rte = NULL;
f_pool = tmp_pool;
LOG_BUFFER_INIT(f_buf);
return interpret(expr);
}
uint
f_eval_int(struct f_inst *expr)
{
/* Called independently in parse-time to eval expressions */
struct f_val res = f_eval(expr, cfg_mem);
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);
}
Reference in a new issue View git blame Copy permalink