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mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-12-22 01:31:55 +00:00

IPv6 BGP support finished. Also simplified the BGP stuff a bit.

This commit is contained in:
Martin Mares 2000-05-04 20:02:56 +00:00
parent 6db8c5a63b
commit cf3d6470d7
3 changed files with 153 additions and 88 deletions

View File

@ -93,10 +93,8 @@ bgp_check_reach_nlri(struct bgp_proto *p, byte *a, int len)
#ifdef IPV6
p->mp_reach_start = a;
p->mp_reach_len = len;
return 0;
#else
return -1;
#endif
return -1;
}
static int
@ -105,10 +103,8 @@ bgp_check_unreach_nlri(struct bgp_proto *p, byte *a, int len)
#ifdef IPV6
p->mp_unreach_start = a;
p->mp_unreach_len = len;
return 0;
#else
return -1;
#endif
return -1;
}
static struct attr_desc bgp_attr_table[] = {
@ -143,20 +139,54 @@ static struct attr_desc bgp_attr_table[] = {
#define ATTR_KNOWN(code) ((code) < ARRAY_SIZE(bgp_attr_table) && bgp_attr_table[code].name)
byte *
bgp_encode_attrs(byte *w, struct bgp_bucket *buck)
static byte *
bgp_set_attr(eattr *e, struct linpool *pool, unsigned attr, unsigned val)
{
ASSERT(ATTR_KNOWN(attr));
e->id = EA_CODE(EAP_BGP, attr);
e->type = bgp_attr_table[attr].type;
e->flags = bgp_attr_table[attr].expected_flags;
if (e->type & EAF_EMBEDDED)
{
e->u.data = val;
return NULL;
}
else
{
e->u.ptr = lp_alloc(pool, sizeof(struct adata) + val);
e->u.ptr->length = val;
return e->u.ptr->data;
}
}
byte *
bgp_attach_attr(ea_list **to, struct linpool *pool, unsigned attr, unsigned val)
{
ea_list *a = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
a->next = *to;
*to = a;
a->flags = EALF_SORTED;
a->count = 1;
return bgp_set_attr(a->attrs, pool, attr, val);
}
unsigned int
bgp_encode_attrs(byte *w, ea_list *attrs, int remains)
{
int remains = 1024;
unsigned int i, code, flags;
byte *start = w;
int len;
w += 2;
for(i=0; i<buck->eattrs->count; i++)
for(i=0; i<attrs->count; i++)
{
eattr *a = &buck->eattrs->attrs[i];
eattr *a = &attrs->attrs[i];
ASSERT(EA_PROTO(a->id) == EAP_BGP);
code = EA_ID(a->id);
#ifdef IPV6
/* When talking multiprotocol BGP, the NEXT_HOP attributes are used only temporarily. */
if (code == BA_NEXT_HOP)
continue;
#endif
flags = a->flags & (BAF_OPTIONAL | BAF_TRANSITIVE | BAF_PARTIAL);
if (ATTR_KNOWN(code))
{
@ -228,8 +258,7 @@ bgp_encode_attrs(byte *w, struct bgp_bucket *buck)
remains -= len;
w += len;
}
put_u16(start, w-start-2);
return w;
return w - start;
}
static void
@ -523,60 +552,36 @@ static int
bgp_create_attrs(struct bgp_proto *p, rte *e, ea_list **attrs, struct linpool *pool)
{
ea_list *ea = lp_alloc(pool, sizeof(ea_list) + 4*sizeof(eattr));
eattr *a = ea->attrs;
rta *rta = e->attrs;
byte *z;
ea->next = *attrs;
*attrs = ea;
ea->flags = EALF_SORTED;
ea->count = 4;
a->id = EA_CODE(EAP_BGP, BA_ORIGIN);
a->flags = BAF_TRANSITIVE;
a->type = EAF_TYPE_INT;
if (rta->source == RTS_RIP_EXT || rta->source == RTS_OSPF_EXT)
a->u.data = ORIGIN_INCOMPLETE;
else
a->u.data = ORIGIN_IGP;
a++;
bgp_set_attr(ea->attrs, pool, BA_ORIGIN,
(rta->source == RTS_RIP_EXT || rta->source == RTS_OSPF_EXT) ? ORIGIN_INCOMPLETE : ORIGIN_IGP);
a->id = EA_CODE(EAP_BGP, BA_AS_PATH);
a->flags = BAF_TRANSITIVE;
a->type = EAF_TYPE_AS_PATH;
if (p->is_internal)
{
a->u.ptr = lp_alloc(pool, sizeof(struct adata));
a->u.ptr->length = 0;
}
bgp_set_attr(ea->attrs+1, pool, BA_AS_PATH, 0);
else
{
byte *z;
a->u.ptr = lp_alloc(pool, sizeof(struct adata) + 4);
a->u.ptr->length = 4;
z = a->u.ptr->data;
z = bgp_set_attr(ea->attrs+1, pool, BA_AS_PATH, 4);
z[0] = AS_PATH_SEQUENCE;
z[1] = 1; /* 1 AS */
put_u16(z+2, p->local_as);
}
a++;
a->id = EA_CODE(EAP_BGP, BA_NEXT_HOP);
a->flags = BAF_TRANSITIVE;
a->type = EAF_TYPE_IP_ADDRESS;
a->u.ptr = lp_alloc(pool, sizeof(struct adata) + sizeof(ip_addr));
a->u.ptr->length = sizeof(ip_addr);
z = bgp_set_attr(ea->attrs+2, pool, BA_NEXT_HOP, sizeof(ip_addr));
if (p->cf->next_hop_self ||
!p->is_internal ||
rta->dest != RTD_ROUTER)
*(ip_addr *)a->u.ptr->data = p->local_addr;
*(ip_addr *)z = p->local_addr;
else
*(ip_addr *)a->u.ptr->data = e->attrs->gw;
a++;
*(ip_addr *)z = e->attrs->gw;
a->id = EA_CODE(EAP_BGP, BA_LOCAL_PREF);
a->flags = BAF_OPTIONAL;
a->type = EAF_TYPE_INT;
a->u.data = 0;
bgp_set_attr(ea->attrs+3, pool, BA_LOCAL_PREF, 0);
return 0; /* Leave decision to the filters */
}
@ -602,8 +607,8 @@ bgp_update_attrs(struct bgp_proto *p, rte *e, ea_list **attrs, struct linpool *p
{
eattr *a;
if (!p->is_internal)
*attrs = bgp_path_prepend(pool, ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH)), *attrs, p->local_as);
if (!p->is_internal && (a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH))))
*attrs = bgp_path_prepend(pool, a, *attrs, p->local_as);
a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_NEXT_HOP));
if (a && (p->is_internal || (!p->is_internal && e->attrs->iface == p->neigh->iface)))
@ -613,18 +618,7 @@ bgp_update_attrs(struct bgp_proto *p, rte *e, ea_list **attrs, struct linpool *p
else
{
/* Need to create new one */
ea_list *ea = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
ea->next = *attrs;
*attrs = ea;
ea->flags = EALF_SORTED;
ea->count = 1;
a = ea->attrs;
a->id = EA_CODE(EAP_BGP, BA_NEXT_HOP);
a->flags = BAF_TRANSITIVE;
a->type = EAF_TYPE_IP_ADDRESS;
a->u.ptr = lp_alloc(pool, sizeof(struct adata) + sizeof(ip_addr));
a->u.ptr->length = sizeof(ip_addr);
*(ip_addr *)a->u.ptr->data = p->local_addr;
*(ip_addr *) bgp_attach_attr(attrs, pool, BA_NEXT_HOP, sizeof(ip_addr)) = p->local_addr;
}
return 0; /* Leave decision to the filters */
@ -884,17 +878,7 @@ bgp_decode_attrs(struct bgp_conn *conn, byte *attr, unsigned int len, struct lin
/* If there's no local preference, define one */
if (!(seen[0] && (1 << BA_LOCAL_PREF)))
{
ea = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
ea->next = a->eattrs;
a->eattrs = ea;
ea->flags = 0;
ea->count = 1;
ea->attrs[0].id = EA_CODE(EAP_BGP, BA_LOCAL_PREF);
ea->attrs[0].flags = BAF_OPTIONAL;
ea->attrs[0].type = EAF_TYPE_INT;
ea->attrs[0].u.data = 0;
}
bgp_attach_attr(&a->eattrs, pool, BA_LOCAL_PREF, 0);
return a;
malformed:

View File

@ -115,13 +115,14 @@ void bgp_close_conn(struct bgp_conn *c);
/* attrs.c */
byte *bgp_attach_attr(struct ea_list **to, struct linpool *, unsigned attr, unsigned val);
struct rta *bgp_decode_attrs(struct bgp_conn *conn, byte *a, unsigned int len, struct linpool *pool, int mandatory);
int bgp_get_attr(struct eattr *e, byte *buf);
int bgp_rte_better(struct rte *, struct rte *);
void bgp_rt_notify(struct proto *, struct network *, struct rte *, struct rte *, struct ea_list *);
int bgp_import_control(struct proto *, struct rte **, struct ea_list **, struct linpool *);
void bgp_attr_init(struct bgp_proto *);
byte *bgp_encode_attrs(byte *w, struct bgp_bucket *buck);
unsigned int bgp_encode_attrs(byte *w, struct ea_list *attrs, int remains);
void bgp_free_bucket(struct bgp_proto *p, struct bgp_bucket *buck);
/* packets.c */

View File

@ -76,10 +76,11 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
struct bgp_proto *p = conn->bgp;
struct bgp_bucket *buck;
int remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - 4;
byte *w, *wold;
byte *w;
ip_addr ip;
int wd_size = 0;
int r_size = 0;
int a_size = 0;
BGP_TRACE(D_PACKETS, "Sending UPDATE");
w = buf+2;
@ -104,9 +105,10 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
continue;
}
DBG("Processing bucket %p\n", buck);
w = bgp_encode_attrs(w, buck);
remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - (w-buf);
r_size = bgp_encode_prefixes(p, w, buck, remains);
a_size = bgp_encode_attrs(w+2, buck->eattrs, 1024);
put_u16(w, a_size);
w += a_size + 2;
r_size = bgp_encode_prefixes(p, w, buck, remains - a_size);
w += r_size;
break;
}
@ -124,7 +126,94 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
static byte *
bgp_create_update(struct bgp_conn *conn, byte *buf)
{
return NULL;
struct bgp_proto *p = conn->bgp;
struct bgp_bucket *buck;
int size, is_ll;
int remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - 4;
byte *w, *tmp, *tstart;
ip_addr ip, ip_ll;
ea_list *ea;
eattr *nh;
neighbor *n;
BGP_TRACE(D_PACKETS, "Sending UPDATE");
put_u16(buf, 0);
w = buf+4;
if ((buck = p->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
{
DBG("Withdrawn routes:\n");
tmp = bgp_attach_attr(&ea, bgp_linpool, BA_MP_UNREACH_NLRI, remains-8);
*tmp++ = 0;
*tmp++ = BGP_AF_IPV6;
*tmp++ = 1;
ea->attrs[0].u.ptr->length = bgp_encode_prefixes(p, tmp, buck, remains-11);
size = bgp_encode_attrs(w, ea, remains);
w += size;
remains -= size;
}
if (remains >= 2048)
{
while ((buck = (struct bgp_bucket *) HEAD(p->bucket_queue))->send_node.next)
{
if (EMPTY_LIST(buck->prefixes))
{
DBG("Deleting empty bucket %p\n", buck);
rem_node(&buck->send_node);
bgp_free_bucket(p, buck);
continue;
}
DBG("Processing bucket %p\n", buck);
size = bgp_encode_attrs(w, buck->eattrs, 1024);
w += size;
remains -= size;
tstart = tmp = bgp_attach_attr(&ea, bgp_linpool, BA_MP_REACH_NLRI, remains-8);
*tmp++ = 0;
*tmp++ = BGP_AF_IPV6;
*tmp++ = 1;
nh = ea_find(buck->eattrs, EA_CODE(EAP_BGP, BA_NEXT_HOP));
ASSERT(nh);
ip = *(ip_addr *) nh->u.ptr->data;
if (ipa_equal(ip, p->local_addr))
is_ll = 1;
else
{
n = neigh_find(&p->p, &ip, 0);
if (n && n->iface == p->neigh->iface)
is_ll = 1;
else
is_ll = 0;
}
if (is_ll)
{
*tmp++ = 32;
ip_ll = ipa_or(ipa_build(0xfe80,0,0,0), ipa_and(ip, ipa_build(0,0,~0,~0)));
ipa_hton(ip);
memcpy(tmp, &ip, 16);
ipa_hton(ip_ll);
memcpy(tmp+16, &ip_ll, 16);
tmp += 32;
}
else
{
*tmp++ = 16;
ipa_hton(ip);
memcpy(tmp, &ip, 16);
tmp += 16;
}
*tmp++ = 0; /* No SNPA information */
tmp += bgp_encode_prefixes(p, tmp, buck, remains - (8+3+32+1));
ea->attrs[0].u.ptr->length = tmp - tstart;
w += bgp_encode_attrs(w, ea, remains);
break;
}
}
size = w - (buf+4);
put_u16(buf+2, size);
lp_flush(bgp_linpool);
return size ? w : NULL;
}
#endif
@ -476,16 +565,7 @@ bgp_do_rx_update(struct bgp_conn *conn,
/* Create fake NEXT_HOP attribute */
if (len < 1 || (*x != 16 && *x != 32) || len < *x + 2)
goto bad;
e->next = a0->eattrs;
a0->eattrs = e;
e->flags = EALF_SORTED;
e->count = 1;
e->attrs[0].id = EA_CODE(EAP_BGP, BA_NEXT_HOP);
e->attrs[0].flags = BAF_TRANSITIVE;
e->attrs[0].type = EAF_TYPE_IP_ADDRESS;
e->attrs[0].u.ptr = ad;
ad->length = 16;
memcpy(ad->data, x+1, 16);
memcpy(bgp_attach_attr(&a0->eattrs, bgp_linpool, BA_NEXT_HOP, 16), x+1, 16);
len -= *x + 1;
x += *x + 1;