From 9f42e93b6a25bff87074156586505a6e8968f8cb Mon Sep 17 00:00:00 2001

Message-Id: <9f42e93b6a25bff87074156586505a6e8968f8cb.1610538323.git.lorenzo.bianconi@redhat.com>

From: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>

Date: Tue, 12 Jan 2021 13:10:56 +0100

Subject: [PATCH] bfd: introduce IPv6 support

Introduce IPv6 support to ovn controller BFD implementation

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>

Acked-by: Mark Michelson <mmichels@redhat.com>

Signed-off-by: Numan Siddique <numans@ovn.org>

---

 NEWS                 |   2 +-

 controller/pinctrl.c | 112 ++++++++++++++++++++++++++++---------------

 tests/system-ovn.at  |  16 ++++++-

 3 files changed, 89 insertions(+), 41 deletions(-)

--- a/NEWS

+++ b/NEWS

@@ -2,7 +2,7 @@ Post-v20.12.0

 -------------------------

   - Support ECMP multiple nexthops for reroute router policies.

    - BFD protocol support according to RFC880 [0]. Introduce next-hop BFD

-     availability check for OVN static routes. IPv6 is not suported yet.

+     availability check for OVN static routes.

      [0] https://tools.ietf.org/html/rfc5880)

 OVN v20.12.0 - 18 Dec 2020

--- a/controller/pinctrl.c

+++ b/controller/pinctrl.c

@@ -6393,10 +6393,10 @@ struct bfd_entry {

     /* L2 source address */

     struct eth_addr src_mac;

-    /* IPv4 source address */

-    ovs_be32 ip_src;

-    /* IPv4 destination address */

-    ovs_be32 ip_dst;

+    /* IP source address */

+    struct in6_addr ip_src;

+    /* IP destination address */

+    struct in6_addr ip_dst;

     /* RFC 5881 section 4

      * The source port MUST be in the range 49152 through 65535.

      * The same UDP source port number MUST be used for all BFD

@@ -6458,20 +6458,17 @@ pinctrl_find_bfd_monitor_entry_by_port(c

 }

 static struct bfd_entry *

-pinctrl_find_bfd_monitor_entry_by_disc(ovs_be32 ip, ovs_be32 disc)

+pinctrl_find_bfd_monitor_entry_by_disc(char *ip, ovs_be32 disc)

 {

-    char *ip_src = xasprintf(IP_FMT, IP_ARGS(ip));

     struct bfd_entry *ret = NULL, *entry;

-    HMAP_FOR_EACH_WITH_HASH (entry, node, hash_string(ip_src, 0),

+    HMAP_FOR_EACH_WITH_HASH (entry, node, hash_string(ip, 0),

                              &bfd_monitor_map) {

         if (entry->local_disc == disc) {

             ret = entry;

             break;

         }

     }

-

-    free(ip_src);

     return ret;

 }

@@ -6501,33 +6498,28 @@ static void

 bfd_monitor_put_bfd_msg(struct bfd_entry *entry, struct dp_packet *packet,

                         bool final)

 {

-    struct udp_header *udp;

-    struct bfd_msg *msg;

+    int payload_len = sizeof(struct udp_header) + sizeof(struct bfd_msg);

     /* Properly align after the ethernet header */

     dp_packet_reserve(packet, 2);

-    struct eth_header *eth = dp_packet_put_uninit(packet, sizeof *eth);

-    eth->eth_dst = eth_addr_broadcast;

-    eth->eth_src = entry->src_mac;

-    eth->eth_type = htons(ETH_TYPE_IP);

-

-    struct ip_header *ip = dp_packet_put_zeros(packet, sizeof *ip);

-    ip->ip_ihl_ver = IP_IHL_VER(5, 4);

-    ip->ip_tot_len = htons(sizeof *ip + sizeof *udp + sizeof *msg);

-    ip->ip_ttl = MAXTTL;

-    ip->ip_tos = IPTOS_PREC_INTERNETCONTROL;

-    ip->ip_proto = IPPROTO_UDP;

-    put_16aligned_be32(&ip->ip_src, entry->ip_src);

-    put_16aligned_be32(&ip->ip_dst, entry->ip_dst);

-    /* Checksum has already been zeroed by put_zeros call. */

-    ip->ip_csum = csum(ip, sizeof *ip);

+    if (IN6_IS_ADDR_V4MAPPED(&entry->ip_src)) {

+        ovs_be32 ip_src = in6_addr_get_mapped_ipv4(&entry->ip_src);

+        ovs_be32 ip_dst = in6_addr_get_mapped_ipv4(&entry->ip_dst);

+        pinctrl_compose_ipv4(packet, entry->src_mac, eth_addr_broadcast,

+                             ip_src, ip_dst, IPPROTO_UDP, MAXTTL, payload_len);

+    } else {

+        pinctrl_compose_ipv6(packet, entry->src_mac, eth_addr_broadcast,

+                             &entry->ip_src, &entry->ip_dst, IPPROTO_UDP,

+                             MAXTTL, payload_len);

+    }

-    udp = dp_packet_put_zeros(packet, sizeof *udp);

+    struct udp_header *udp = dp_packet_put_zeros(packet, sizeof *udp);

+    udp->udp_len = htons(payload_len);

+    udp->udp_csum = 0;

     udp->udp_src = htons(entry->udp_src);

     udp->udp_dst = htons(BFD_DEST_PORT);

-    udp->udp_len = htons(sizeof *udp + sizeof *msg);

-    msg = dp_packet_put_zeros(packet, sizeof *msg);

+    struct bfd_msg *msg = dp_packet_put_zeros(packet, sizeof *msg);

     msg->vers_diag = (BFD_VERSION << 5);

     msg->mult = entry->local_mult;

     msg->length = BFD_PACKET_LEN;

@@ -6538,6 +6530,17 @@ bfd_monitor_put_bfd_msg(struct bfd_entry

     /* min_tx and min_rx are in us - RFC 5880 page 9 */

     msg->min_tx = htonl(entry->local_min_tx * 1000);

     msg->min_rx = htonl(entry->local_min_rx * 1000);

+

+    if (!IN6_IS_ADDR_V4MAPPED(&entry->ip_src)) {

+        /* IPv6 needs UDP checksum calculated */

+        uint32_t csum = packet_csum_pseudoheader6(dp_packet_l3(packet));

+        int len = (uint8_t *)udp - (uint8_t *)dp_packet_eth(packet);

+        csum = csum_continue(csum, udp, dp_packet_size(packet) - len);

+        udp->udp_csum = csum_finish(csum);

+        if (!udp->udp_csum) {

+            udp->udp_csum = htons(0xffff);

+        }

+    }

 }

 static void

@@ -6736,9 +6739,18 @@ pinctrl_handle_bfd_msg(struct rconn *swc

         return;

     }

+    char *ip_src;

+    if (ip_flow->dl_type == htons(ETH_TYPE_IP)) {

+        ip_src = normalize_ipv4_prefix(ip_flow->nw_src, 32);

+    } else {

+        ip_src = normalize_ipv6_prefix(&ip_flow->ipv6_src, 128);

+    }

+

     const struct bfd_msg *msg = dp_packet_get_udp_payload(pkt_in);

-    struct bfd_entry *entry = pinctrl_find_bfd_monitor_entry_by_disc(

-            ip_flow->nw_src, msg->your_disc);

+    struct bfd_entry *entry =

+        pinctrl_find_bfd_monitor_entry_by_disc(ip_src, msg->your_disc);

+    free(ip_src);

+

     if (!entry) {

         return;

     }

@@ -6821,10 +6833,21 @@ static void

 bfd_monitor_check_sb_conf(const struct sbrec_bfd *sb_bt,

                           struct bfd_entry *entry)

 {

-    ovs_be32 ip_dst;

+    struct lport_addresses dst_addr;

+

+    if (extract_ip_addresses(sb_bt->dst_ip, &dst_addr)) {

+        struct in6_addr addr;

+

+        if (dst_addr.n_ipv6_addrs > 0) {

+            addr = dst_addr.ipv6_addrs[0].addr;

+        } else {

+            addr = in6_addr_mapped_ipv4(dst_addr.ipv4_addrs[0].addr);

+        }

-    if (ip_parse(sb_bt->dst_ip, &ip_dst) && ip_dst != entry->ip_dst) {

-        entry->ip_dst = ip_dst;

+        if (!ipv6_addr_equals(&addr, &entry->ip_dst)) {

+            entry->ip_dst = addr;

+        }

+        destroy_lport_addresses(&dst_addr);

     }

     if (sb_bt->min_tx != entry->local_min_tx) {

@@ -6889,11 +6912,15 @@ bfd_monitor_run(struct ovsdb_idl_txn *ov

         entry = pinctrl_find_bfd_monitor_entry_by_port(

                 bt->dst_ip, bt->src_port);

         if (!entry) {

-            ovs_be32 ip_dst, ip_src = htonl(BFD_DEFAULT_SRC_IP);

             struct eth_addr ea = eth_addr_zero;

+            struct lport_addresses dst_addr;

+            struct in6_addr ip_src, ip_dst;

             int i;

-            if (!ip_parse(bt->dst_ip, &ip_dst)) {

+            ip_dst = in6_addr_mapped_ipv4(htonl(BFD_DEFAULT_DST_IP));

+            ip_src = in6_addr_mapped_ipv4(htonl(BFD_DEFAULT_SRC_IP));

+

+            if (!extract_ip_addresses(bt->dst_ip, &dst_addr)) {

                 continue;

             }

@@ -6905,13 +6932,20 @@ bfd_monitor_run(struct ovsdb_idl_txn *ov

                 }

                 ea = laddrs.ea;

-                if (laddrs.n_ipv4_addrs > 0) {

-                    ip_src = laddrs.ipv4_addrs[0].addr;

+                if (dst_addr.n_ipv6_addrs > 0 && laddrs.n_ipv6_addrs > 0) {

+                    ip_dst = dst_addr.ipv6_addrs[0].addr;

+                    ip_src = laddrs.ipv6_addrs[0].addr;

+                    destroy_lport_addresses(&laddrs);

+                    break;

+                } else if (laddrs.n_ipv4_addrs > 0) {

+                    ip_dst = in6_addr_mapped_ipv4(dst_addr.ipv4_addrs[0].addr);

+                    ip_src = in6_addr_mapped_ipv4(laddrs.ipv4_addrs[0].addr);

                     destroy_lport_addresses(&laddrs);

                     break;

                 }

                 destroy_lport_addresses(&laddrs);

             }

+            destroy_lport_addresses(&dst_addr);

             if (eth_addr_is_zero(ea)) {

                 continue;

--- a/tests/system-ovn.at

+++ b/tests/system-ovn.at

@@ -5563,7 +5563,7 @@ check ovn-nbctl ls-add public

 check ovn-nbctl lrp-add R1 rp-sw0 00:00:01:01:02:03 192.168.1.1/24

 check ovn-nbctl lrp-add R1 rp-sw1 00:00:03:01:02:03 192.168.2.1/24

-check ovn-nbctl lrp-add R1 rp-public 00:00:02:01:02:03 172.16.1.1/24 \

+check ovn-nbctl lrp-add R1 rp-public 00:00:02:01:02:03 172.16.1.1/24 1000::a/64 \

     -- lrp-set-gateway-chassis rp-public hv1

 check ovn-nbctl lsp-add sw0 sw0-rp -- set Logical_Switch_Port sw0-rp \

@@ -5593,6 +5593,7 @@ ADD_NAMESPACES(server)

 NS_CHECK_EXEC([server], [ip link set dev lo up])

 ADD_VETH(s1, server, br-ext, "172.16.1.50/24", "f0:00:00:01:02:05", \

          "172.16.1.1")

+NS_CHECK_EXEC([server], [ip addr add 1000::b/64 dev s1])

 AT_CHECK([ovs-vsctl set Open_vSwitch . external-ids:ovn-bridge-mappings=phynet:br-ext])

 check ovn-nbctl lsp-add public public1 \

@@ -5652,6 +5653,19 @@ sleep 5

 kill $(pidof tcpdump)

 AT_CHECK([grep -qi bfd bfd.pcap],[1])

+uuid_v6=$(ovn-nbctl create bfd logical_port=rp-public dst_ip=\"1000::b\")

+check ovn-nbctl lr-route-add R1 2000::/64 1000::b

+route_uuid_v6=$(fetch_column nb:logical_router_static_route _uuid ip_prefix=\"2000::/64\")

+ovn-nbctl set logical_router_static_route $route_uuid_v6 bfd=$uuid_v6

+check ovn-nbctl --wait=hv sync

+NS_CHECK_EXEC([server], [bfdd-beacon --listen=1000::b], [0])

+NS_CHECK_EXEC([server], [bfdd-control allow 1000::a], [0], [dnl

+Allowing connections from 1000::a

+])

+

+wait_column "up" nb:bfd status logical_port=rp-public

+ovn-nbctl destroy bfd $uuid_v6

+

 kill $(pidof ovn-controller)

 as ovn-sb