BGP: Partial support for IPv4 routes with IPv6 next hop (RFC 5549) (d8022d26) · Commits · 戴 / Bird

proto/bgp/attrs.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1285,6 +1285,8 @@ bgp_import_control(struct proto P, rte new, ea_list *attrs UNUSED, struct li
		if (src == NULL)
		return 0;

		// XXXX: Check next hop AF

		/* IBGP route reflection, RFC 4456 */
		if (p->is_internal && src->is_internal && (p->local_as == src->local_as))
		{

proto/bgp/bgp.c

+15 −0

Original line number	Diff line number	Diff line
		@@ -521,6 +521,7 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
		if (peer->gr_aware)
		c->load_state = BFS_LOADING;

		c->ext_next_hop = c->cf->ext_next_hop && (bgp_channel_is_ipv6(c) \|\| rem->ext_next_hop);
		c->add_path_rx = (loc->add_path & BGP_ADD_PATH_RX) && (rem->add_path & BGP_ADD_PATH_TX);
		c->add_path_tx = (loc->add_path & BGP_ADD_PATH_TX) && (rem->add_path & BGP_ADD_PATH_RX);

		@@ -1788,6 +1789,7 @@ bgp_show_capabilities(struct bgp_proto p UNUSED, struct bgp_caps caps)
		uint any_mp_bgp = 0;
		uint any_gr_able = 0;
		uint any_add_path = 0;
		uint any_ext_next_hop = 0;
		u32 afl1 = alloca(caps->af_count sizeof(u32));
		u32 afl2 = alloca(caps->af_count sizeof(u32));
		uint afn1, afn2;
		@@ -1797,6 +1799,7 @@ bgp_show_capabilities(struct bgp_proto p UNUSED, struct bgp_caps caps)
		any_mp_bgp \|= ac->ready;
		any_gr_able \|= ac->gr_able;
		any_add_path \|= ac->add_path;
		any_ext_next_hop \|= ac->ext_next_hop;
		}

		if (any_mp_bgp)
		@@ -1814,6 +1817,18 @@ bgp_show_capabilities(struct bgp_proto p UNUSED, struct bgp_caps caps)
		if (caps->route_refresh)
		cli_msg(-1006, " Route refresh");

		if (any_ext_next_hop)
		{
		cli_msg(-1006, " Extended next hop");

		afn1 = 0;
		WALK_AF_CAPS(caps, ac)
		if (ac->ext_next_hop)
		afl1[afn1++] = ac->afi;

		bgp_show_afis(-1006, " IPv6 nexthop:", afl1, afn1);
		}

		if (caps->ext_messages)
		cli_msg(-1006, " Extended message");

proto/bgp/bgp.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -123,6 +123,7 @@ struct bgp_channel_config {
		u8 gw_mode; /* How we compute route gateway from next_hop attr, see GW_* */
		u8 secondary; /* Accept also non-best routes (i.e. RA_ACCEPTED) */
		u8 gr_able; /* Allow full graceful restart for the channel */
		u8 ext_next_hop; /* Allow both IPv4 and IPv6 next hops */
		u8 add_path; /* Use ADD-PATH extension [RFC 7911] */

		struct rtable_config igp_table; / Table used for recursive next hop lookups */
		@@ -154,6 +155,7 @@ struct bgp_af_caps {
		u8 ready; /* Multiprotocol capability, RFC 4760 */
		u8 gr_able; /* Graceful restart support, RFC 4724 */
		u8 gr_af_flags; /* Graceful restart per-AF flags */
		u8 ext_next_hop; /* Extended IPv6 next hop, RFC 5549 */
		u8 add_path; /* Multiple paths support, RFC 7911 */
		};

		@@ -274,6 +276,8 @@ struct bgp_channel {
		u8 gr_ready; /* Neighbor could do GR on this AF */
		u8 gr_active; /* Neighbor is doing GR and keeping fwd state */

		u8 ext_next_hop; /* Session allows both IPv4 and IPv6 next hops */

		u8 add_path_rx; /* Session expects receive of ADD-PATH extended NLRI */
		u8 add_path_tx; /* Session expects transmit of ADD-PATH extended NLRI */

proto/bgp/config.Y

+1 −0

Original line number	Diff line number	Diff line
		@@ -169,6 +169,7 @@ bgp_channel_item:
		\| GATEWAY RECURSIVE { BGP_CC->gw_mode = GW_RECURSIVE; }
		\| SECONDARY bool { BGP_CC->secondary = $2; }
		\| GRACEFUL RESTART bool { BGP_CC->gr_able = $3; }
		\| EXTENDED NEXT HOP bool { BGP_CC->ext_next_hop = $4; }
		\| ADD PATHS RX { BGP_CC->add_path = BGP_ADD_PATH_RX; }
		\| ADD PATHS TX { BGP_CC->add_path = BGP_ADD_PATH_TX; }
		\| ADD PATHS bool { BGP_CC->add_path = $3 ? BGP_ADD_PATH_FULL : 0; }

proto/bgp/packets.c

+38 −0

Original line number	Diff line number	Diff line
		@@ -228,6 +228,7 @@ bgp_write_capabilities(struct bgp_conn conn, byte buf)
		struct bgp_channel *c;
		struct bgp_caps *caps;
		struct bgp_af_caps *ac;
		uint any_ext_next_hop = 0;
		uint any_add_path = 0;
		byte *data;

		@@ -259,6 +260,9 @@ bgp_write_capabilities(struct bgp_conn conn, byte buf)
		ac->afi = c->afi;
		ac->ready = 1;

		ac->ext_next_hop = bgp_channel_is_ipv4(c) && c->cf->ext_next_hop;
		any_ext_next_hop \|= ac->ext_next_hop;

		ac->add_path = c->cf->add_path;
		any_add_path \|= ac->add_path;

		@@ -298,6 +302,23 @@ bgp_write_capabilities(struct bgp_conn conn, byte buf)
		buf++ = 0; / Capability data length */
		}

		if (any_ext_next_hop)
		{
		buf++ = 5; / Capability 5: Support for extended next hop */
		buf++ = 0; / Capability data length, will be fixed later */
		data = buf;

		WALK_AF_CAPS(caps, ac)
		if (ac->ext_next_hop)
		{
		put_af4(buf, ac->afi);
		put_u16(buf+4, BGP_AFI_IPV6);
		buf += 6;
		}

		data[-1] = buf - data;
		}

		if (caps->ext_messages)
		{
		buf++ = 6; / Capability 6: Support for extended messages */
		@@ -394,6 +415,23 @@ bgp_read_capabilities(struct bgp_conn conn, struct bgp_caps caps, byte *pos, i
		caps->route_refresh = 1;
		break;

		case 5: /* Extended next hop encoding capability, RFC 5549 */
		if (cl % 6)
		goto err;

		for (i = 0; i < cl; i += 6)
		{
		/* Specified only for IPv4 prefixes with IPv6 next hops */
		if ((get_u16(pos+2+i+0) != BGP_AFI_IPV4) \|\|
		(get_u16(pos+2+i+4) != BGP_AFI_IPV6))
		continue;

		af = get_af4(pos+2+i);
		ac = bgp_get_af_caps(caps, af);
		ac->ext_next_hop = 1;
		}
		break;

		case 6: /* Extended message length capability, RFC draft */
		if (cl != 0)
		goto err;

Admin message