Merge pull request #3600 from opensourcerouting/bfd-zebra-if

bfdd: use zebra API to learn about interfaces

bfdd/bfd.c

@@ -540,6 +540,7 @@ static void bfd_session_free(struct bfd_session *bs)
 struct bfd_session *ptm_bfd_sess_new(struct bfd_peer_cfg *bpc)
 {
 	struct bfd_session *bfd, *l_bfd;
+	struct interface *ifp = NULL;
 	int psock;
 
 	/* check to see if this needs a new session */
@@ -552,6 +553,24 @@ struct bfd_session *ptm_bfd_sess_new(struct bfd_peer_cfg *bpc)
 			return NULL;
 	}
 
+	/*
+	 * No session found, we have to allocate a new one.
+	 *
+	 * First a few critical checks:
+	 *
+	 *   * Check that the specified interface exists.
+	 *   * Attempt to create the UDP socket (might fail if we exceed
+	 *     our limits).
+	 */
+	if (bpc->bpc_has_localif) {
+		ifp = if_lookup_by_name(bpc->bpc_localif, VRF_DEFAULT);
+		if (ifp == NULL) {
+			log_error(
+				"session-new: specified interface doesn't exists.");
+			return NULL;
+		}
+	}
+
 	/*
 	 * Get socket for transmitting control packets.  Note that if we
 	 * could use the destination port (3784) for the source
@@ -574,19 +593,21 @@ struct bfd_session *ptm_bfd_sess_new(struct bfd_peer_cfg *bpc)
 		return NULL;
 	}
 
-	if (bpc->bpc_has_localif && !bpc->bpc_mhop) {
+	if (bpc->bpc_has_localif && !bpc->bpc_mhop)
-		bfd->ifindex = ptm_bfd_fetch_ifindex(bpc->bpc_localif);
+		bfd->ifp = ifp;
-		ptm_bfd_fetch_local_mac(bpc->bpc_localif, bfd->local_mac);
-	}
 
 	if (bpc->bpc_ipv4 == false) {
 		BFD_SET_FLAG(bfd->flags, BFD_SESS_FLAG_IPV6);
 
 		/* Set the IPv6 scope id for link-local addresses. */
 		if (IN6_IS_ADDR_LINKLOCAL(&bpc->bpc_local.sa_sin6.sin6_addr))
-			bpc->bpc_local.sa_sin6.sin6_scope_id = bfd->ifindex;
+			bpc->bpc_local.sa_sin6.sin6_scope_id =
+				bfd->ifp != NULL ? bfd->ifp->ifindex
+						 : IFINDEX_INTERNAL;
 		if (IN6_IS_ADDR_LINKLOCAL(&bpc->bpc_peer.sa_sin6.sin6_addr))
-			bpc->bpc_peer.sa_sin6.sin6_scope_id = bfd->ifindex;
+			bpc->bpc_peer.sa_sin6.sin6_scope_id =
+				bfd->ifp != NULL ? bfd->ifp->ifindex
+						 : IFINDEX_INTERNAL;
 	}
 
 	/* Initialize the session */

bfdd/bfd.h

@@ -31,6 +31,7 @@
 #include "lib/libfrr.h"
 #include "lib/qobj.h"
 #include "lib/queue.h"
+#include "lib/vrf.h"
 
 #include "bfdctl.h"
 
@@ -237,7 +238,7 @@ struct bfd_session {
 
 	struct sockaddr_any local_address;
 	struct sockaddr_any local_ip;
-	int ifindex;
+	struct interface *ifp;
 	uint8_t local_mac[ETHERNET_ADDRESS_LENGTH];
 	uint8_t peer_mac[ETHERNET_ADDRESS_LENGTH];
 
@@ -512,7 +513,6 @@ struct bfd_session *ptm_bfd_sess_new(struct bfd_peer_cfg *bpc);
 int ptm_bfd_ses_del(struct bfd_peer_cfg *bpc);
 void ptm_bfd_ses_dn(struct bfd_session *bfd, uint8_t diag);
 void ptm_bfd_ses_up(struct bfd_session *bfd);
-void fetch_portname_from_ifindex(int ifindex, char *ifname, size_t ifnamelen);
 void ptm_bfd_echo_stop(struct bfd_session *bfd, int polling);
 void ptm_bfd_echo_start(struct bfd_session *bfd);
 void ptm_bfd_xmt_TO(struct bfd_session *bfd, int fbit);
@@ -584,20 +584,4 @@ void bfdd_zclient_stop(void);
 
 int ptm_bfd_notify(struct bfd_session *bs);
 
-
-/*
- * OS compatibility functions.
- */
-#if defined(BFD_LINUX) || defined(BFD_BSD)
-int ptm_bfd_fetch_ifindex(const char *ifname);
-void ptm_bfd_fetch_local_mac(const char *ifname, uint8_t *mac);
-void fetch_portname_from_ifindex(int ifindex, char *ifname, size_t ifnamelen);
-#endif /* BFD_LINUX || BFD_BSD */
-
-#ifdef BFD_BSD
-ssize_t bsd_echo_sock_read(int sd, uint8_t *buf, ssize_t *buflen,
-			   struct sockaddr_storage *ss, socklen_t *sslen,
-			   uint8_t *ttl, uint32_t *id);
-#endif /* BFD_BSD */
-
 #endif /* _BFD_H_ */

bfdd/bfd_packet.c

@@ -241,6 +241,7 @@ ssize_t bfd_recv_ipv4(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl,
 		      size_t vrfnamelen, struct sockaddr_any *local,
 		      struct sockaddr_any *peer)
 {
+	struct interface *ifp;
 	struct cmsghdr *cm;
 	int ifindex;
 	ssize_t mlen;
@@ -307,8 +308,14 @@ ssize_t bfd_recv_ipv4(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl,
 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 			local->sa_sin.sin_len = sizeof(local->sa_sin);
 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
-			fetch_portname_from_ifindex(pi->ipi_ifindex, port,
+
-						    portlen);
+			ifp = if_lookup_by_index(pi->ipi_ifindex, VRF_DEFAULT);
+			if (ifp == NULL)
+				break;
+
+			if (strlcpy(port, ifp->name, portlen) >= portlen)
+				log_debug(
+					"ipv4-recv: interface name truncated");
 			break;
 		}
 #endif /* BFD_LINUX */
@@ -345,8 +352,15 @@ ssize_t bfd_recv_ipv4(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl,
 	/* OS agnostic way of getting interface name. */
 	if (port[0] == 0) {
 		ifindex = getsockopt_ifindex(AF_INET, &msghdr);
-		if (ifindex > 0)
+		if (ifindex <= 0)
-			fetch_portname_from_ifindex(ifindex, port, portlen);
+			return mlen;
+
+		ifp = if_lookup_by_index(ifindex, VRF_DEFAULT);
+		if (ifp == NULL)
+			return mlen;
+
+		if (strlcpy(port, ifp->name, portlen) >= portlen)
+			log_debug("ipv4-recv: interface name truncated");
 	}
 
 	return mlen;
@@ -357,6 +371,7 @@ ssize_t bfd_recv_ipv6(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl,
 		      size_t vrfnamelen, struct sockaddr_any *local,
 		      struct sockaddr_any *peer)
 {
+	struct interface *ifp;
 	struct cmsghdr *cm;
 	struct in6_pktinfo *pi6 = NULL;
 	int ifindex = 0;
@@ -413,9 +428,16 @@ ssize_t bfd_recv_ipv6(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl,
 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 				local->sa_sin6.sin6_len = sizeof(local->sa_sin6);
 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
-				fetch_portname_from_ifindex(pi6->ipi6_ifindex,
+
-							    port, portlen);
 				ifindex = pi6->ipi6_ifindex;
+				ifp = if_lookup_by_index(ifindex, VRF_DEFAULT);
+				if (ifp == NULL)
+					break;
+
+				if (strlcpy(port, ifp->name, portlen)
+				    >= portlen)
+					log_debug(
+						"ipv6-recv: interface name truncated");
 			}
 		}
 	}
@@ -610,8 +632,8 @@ int bfd_recv_cb(struct thread *t)
 	 * If no interface was detected, save the interface where the
 	 * packet came in.
 	 */
-	if (bfd->ifindex == 0)
+	if (bfd->ifp == NULL)
-		bfd->ifindex = ptm_bfd_fetch_ifindex(port);
+		bfd->ifp = if_lookup_by_name(port, VRF_DEFAULT);
 
 	/* Log remote discriminator changes. */
 	if ((bfd->discrs.remote_discr != 0)
@@ -1046,7 +1068,8 @@ int bp_peer_socket(struct bfd_peer_cfg *bpc)
 
 int bp_peer_socketv6(struct bfd_peer_cfg *bpc)
 {
-	int sd, pcount, ifindex;
+	struct interface *ifp;
+	int sd, pcount;
 	struct sockaddr_in6 sin6;
 	static int srcPort = BFD_SRCPORTINIT;
 
@@ -1076,9 +1099,11 @@ int bp_peer_socketv6(struct bfd_peer_cfg *bpc)
 	sin6.sin6_len = sizeof(sin6);
 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
 	sin6 = bpc->bpc_local.sa_sin6;
-	ifindex = ptm_bfd_fetch_ifindex(bpc->bpc_localif);
+	if (IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr)) {
-	if (IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr))
+		ifp = if_lookup_by_name(bpc->bpc_localif, VRF_DEFAULT);
-		sin6.sin6_scope_id = ifindex;
+		sin6.sin6_scope_id =
+			(ifp != NULL) ? ifp->ifindex : IFINDEX_INTERNAL;
+	}
 
 	if (bpc->bpc_has_localif) {
 		if (bp_bind_dev(sd, bpc->bpc_localif) != 0) {

bfdd/bsd.c

@@ -35,70 +35,6 @@
 /*
  * Definitions.
  */
-int ptm_bfd_fetch_ifindex(const char *ifname)
-{
-	return if_nametoindex(ifname);
-}
-
-void ptm_bfd_fetch_local_mac(const char *ifname, uint8_t *mac)
-{
-	struct ifaddrs *ifap, *ifa;
-	struct if_data *ifi;
-	struct sockaddr_dl *sdl;
-	size_t maclen;
-
-	/* Always clean the target, zeroed macs mean failure. */
-	memset(mac, 0, ETHERNET_ADDRESS_LENGTH);
-
-	if (getifaddrs(&ifap) != 0)
-		return;
-
-	for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
-		/* Find interface with that name. */
-		if (strcmp(ifa->ifa_name, ifname) != 0)
-			continue;
-		/* Skip non link addresses. We want the MAC address. */
-		if (ifa->ifa_addr->sa_family != AF_LINK)
-			continue;
-
-		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
-		ifi = (struct if_data *)ifa->ifa_data;
-		/* Skip non ethernet related data. */
-		if (ifi->ifi_type != IFT_ETHER)
-			continue;
-
-		if (sdl->sdl_alen != ETHERNET_ADDRESS_LENGTH)
-			log_warning("%s:%d mac address length %d (expected %d)",
-				    __func__, __LINE__, sdl->sdl_alen,
-				    ETHERNET_ADDRESS_LENGTH);
-
-		maclen = (sdl->sdl_alen > ETHERNET_ADDRESS_LENGTH)
-				 ? ETHERNET_ADDRESS_LENGTH
-				 : sdl->sdl_alen;
-		memcpy(mac, LLADDR(sdl), maclen);
-		break;
-	}
-
-	freeifaddrs(ifap);
-}
-
-
-/* Was _fetch_portname_from_ifindex() */
-void fetch_portname_from_ifindex(int ifindex, char *ifname, size_t ifnamelen)
-{
-	char ifname_tmp[IF_NAMESIZE];
-
-	/* Set ifname to empty to signalize failures. */
-	memset(ifname, 0, ifnamelen);
-
-	if (if_indextoname(ifindex, ifname_tmp) == NULL)
-		return;
-
-	if (strlcpy(ifname, ifname_tmp, ifnamelen) > ifnamelen)
-		log_warning("%s:%d interface name truncated", __func__,
-			    __LINE__);
-}
-
 int bp_bind_dev(int sd, const char *dev)
 {
 	/*

bfdd/linux.c

@@ -29,64 +29,6 @@
 /*
  * Definitions.
  */
-int ptm_bfd_fetch_ifindex(const char *ifname)
-{
-	struct ifreq ifr;
-
-	if (strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name))
-	    > sizeof(ifr.ifr_name))
-		log_error("interface-to-index: name truncated ('%s' -> '%s')",
-			  ifr.ifr_name, ifname);
-
-	if (ioctl(bglobal.bg_shop, SIOCGIFINDEX, &ifr) == -1) {
-		log_error("interface-to-index: %s translation failed: %s",
-			  ifname, strerror(errno));
-		return -1;
-	}
-
-	return ifr.ifr_ifindex;
-}
-
-void ptm_bfd_fetch_local_mac(const char *ifname, uint8_t *mac)
-{
-	struct ifreq ifr;
-
-	if (strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name))
-	    > sizeof(ifr.ifr_name))
-		log_error("interface-mac: name truncated ('%s' -> '%s')",
-			  ifr.ifr_name, ifname);
-
-	if (ioctl(bglobal.bg_shop, SIOCGIFHWADDR, &ifr) == -1) {
-		log_error("interface-mac: %s MAC retrieval failed: %s", ifname,
-			  strerror(errno));
-		return;
-	}
-
-	memcpy(mac, ifr.ifr_hwaddr.sa_data, ETHERNET_ADDRESS_LENGTH);
-}
-
-
-/* Was _fetch_portname_from_ifindex() */
-void fetch_portname_from_ifindex(int ifindex, char *ifname, size_t ifnamelen)
-{
-	struct ifreq ifr;
-
-	ifname[0] = 0;
-
-	memset(&ifr, 0, sizeof(ifr));
-	ifr.ifr_ifindex = ifindex;
-
-	if (ioctl(bglobal.bg_shop, SIOCGIFNAME, &ifr) == -1) {
-		log_error("index-to-interface: index %d failure: %s", ifindex,
-			  strerror(errno));
-		return;
-	}
-
-	if (strlcpy(ifname, ifr.ifr_name, ifnamelen) >= ifnamelen)
-		log_debug("index-to-interface: name truncated '%s' -> '%s'",
-			  ifr.ifr_name, ifname);
-}
-
 int bp_bind_dev(int sd __attribute__((__unused__)),
 		const char *dev __attribute__((__unused__)))
 {

bfdd/ptm_adapter.c

@@ -189,7 +189,10 @@ int ptm_bfd_notify(struct bfd_session *bs)
 	stream_putl(msg, ZEBRA_INTERFACE_BFD_DEST_UPDATE);
 
 	/* NOTE: Interface is a shortcut to avoid comparing source address. */
-	stream_putl(msg, bs->ifindex);
+	if (bs->ifp != NULL)
+		stream_putl(msg, bs->ifp->ifindex);
+	else
+		stream_putl(msg, IFINDEX_INTERNAL);
 
 	/* BFD destination prefix information. */
 	if (BFD_CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH))
@@ -287,6 +290,7 @@ stream_failure:
 static int _ptm_msg_read(struct stream *msg, int command,
 			 struct bfd_peer_cfg *bpc, struct ptm_client **pc)
 {
+	struct interface *ifp;
 	uint32_t pid;
 	uint8_t ttl __attribute__((unused));
 	size_t ifnamelen;
@@ -393,9 +397,19 @@ static int _ptm_msg_read(struct stream *msg, int command,
 			 */
 			if (bpc->bpc_ipv4 == false
 			    && IN6_IS_ADDR_LINKLOCAL(
-				       &bpc->bpc_peer.sa_sin6.sin6_addr))
+				       &bpc->bpc_peer.sa_sin6.sin6_addr)) {
+				ifp = if_lookup_by_name_all_vrf(
+					bpc->bpc_localif);
+				if (ifp == NULL) {
+					log_error(
+						"ptm-read: interface %s doesn't exists",
+						bpc->bpc_localif);
+					return -1;
+				}
+
 				bpc->bpc_peer.sa_sin6.sin6_scope_id =
-					ptm_bfd_fetch_ifindex(bpc->bpc_localif);
+					ifp->ifindex;
+			}
 		}
 	}
 
@@ -576,9 +590,34 @@ static void bfdd_zebra_connected(struct zclient *zc)
 	stream_putl(msg, ZEBRA_BFD_DEST_REPLAY);
 	stream_putw_at(msg, 0, stream_get_endp(msg));
 
+	/* Ask for interfaces information. */
+	zclient_create_header(msg, ZEBRA_INTERFACE_ADD, VRF_DEFAULT);
+
+	/* Send requests. */
 	zclient_send_message(zclient);
 }
 
+static int bfdd_interface_update(int cmd, struct zclient *zc, uint16_t len,
+				 vrf_id_t vrfid)
+{
+	/*
+	 * `zebra_interface_add_read` will handle the interface creation
+	 * on `lib/if.c`. We'll use that data structure instead of
+	 * rolling our own.
+	 */
+	if (cmd == ZEBRA_INTERFACE_ADD) {
+		zebra_interface_add_read(zc->ibuf, vrfid);
+		return 0;
+	}
+
+	/* Update interface information. */
+	zebra_interface_state_read(zc->ibuf, vrfid);
+
+	/* TODO: stop all sessions using this interface. */
+
+	return 0;
+}
+
 void bfdd_zclient_init(struct zebra_privs_t *bfdd_priv)
 {
 	zclient = zclient_new(master, &zclient_options_default);
@@ -594,6 +633,10 @@ void bfdd_zclient_init(struct zebra_privs_t *bfdd_priv)
 
 	/* Send replay request on zebra connect. */
 	zclient->zebra_connected = bfdd_zebra_connected;
+
+	/* Learn interfaces from zebra instead of the OS. */
+	zclient->interface_add = bfdd_interface_update;
+	zclient->interface_delete = bfdd_interface_update;
 }
 
 void bfdd_zclient_stop(void)