[ovs-dev,v7,ovn,1/2] controller: add ipv6 prefix delegation state machine
diff mbox series

Message ID fce22013d1a3719dd91bb69b4132b454cf63826b.1584540892.git.lorenzo.bianconi@redhat.com
State New
Headers show
Series
  • Add IPv6 Prefix delegation (RFC3633)
Related show

Commit Message

Lorenzo Bianconi March 18, 2020, 2:18 p.m. UTC
Introduce IPv6 Prefix delegation state machine according to RFC 3633
https://tools.ietf.org/html/rfc3633.
Add handle_dhcpv6_reply controller action to parse advertise/reply from
IPv6 delegation server. Advertise/reply are parsed running respectively:
- pinctrl_parse_dhcv6_advt
- pinctrl_parse_dhcv6_reply
The IPv6 requesting router starts sending dhcpv6 solicit through the logical
router port marked with ipv6_prefix_delegation set to true.
An IPv6 prefix will be requested for each logical router port marked
with "prefix" set to true in option column of logical router port table.
Save IPv6 prefix received by IPv6 delegation router in the options columns of
SB port binding table in order to be reused by Router Advertisement framework
run by ovn logical router pipeline.
IPv6 Prefix delegation state machine is enabled on Gateway Router or on
a Gateway Router Port

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
---
 controller/pinctrl.c  | 659 +++++++++++++++++++++++++++++++++++++++++-
 controller/pinctrl.h  |   1 +
 include/ovn/actions.h |   8 +-
 lib/actions.c         |  16 +
 lib/ovn-l7.h          |  19 ++
 ovn-sb.xml            |  18 ++
 tests/ovn.at          |   4 +
 utilities/ovn-trace.c |   2 +
 8 files changed, 719 insertions(+), 8 deletions(-)

Patch
diff mbox series

diff --git a/controller/pinctrl.c b/controller/pinctrl.c
index 8bf19776c..c705a3244 100644
--- a/controller/pinctrl.c
+++ b/controller/pinctrl.c
@@ -270,6 +270,19 @@  static void pinctrl_ip_mcast_handle(
     const struct match *md,
     struct ofpbuf *userdata);
 
+static void init_ipv6_prefixd(void);
+static void destroy_ipv6_prefixd(void);
+static void ipv6_prefixd_wait(long long int timeout);
+static void
+prepare_ipv6_prefixd(struct ovsdb_idl_txn *ovnsb_idl_txn,
+                     struct ovsdb_idl_index *sbrec_port_binding_by_name,
+                     const struct hmap *local_datapaths,
+                     const struct sbrec_chassis *chassis,
+                     const struct sset *active_tunnels)
+    OVS_REQUIRES(pinctrl_mutex);
+static void
+send_ipv6_prefixd(struct rconn *swconn, long long int *send_prefixd_time)
+    OVS_REQUIRES(pinctrl_mutex);
 static bool may_inject_pkts(void);
 
 static void init_put_vport_bindings(void);
@@ -313,6 +326,10 @@  static void pinctrl_compose_ipv6(struct dp_packet *packet,
                                  uint8_t ip_proto, uint8_t ttl,
                                  uint16_t ip_payload_len);
 
+static void
+put_load(uint64_t value, enum mf_field_id dst, int ofs, int n_bits,
+         struct ofpbuf *ofpacts);
+
 COVERAGE_DEFINE(pinctrl_drop_put_mac_binding);
 COVERAGE_DEFINE(pinctrl_drop_buffered_packets_map);
 COVERAGE_DEFINE(pinctrl_drop_controller_event);
@@ -470,6 +487,7 @@  pinctrl_init(void)
     init_put_mac_bindings();
     init_send_garps_rarps();
     init_ipv6_ras();
+    init_ipv6_prefixd();
     init_buffered_packets_map();
     init_event_table();
     ip_mcast_snoop_init();
@@ -557,6 +575,49 @@  set_actions_and_enqueue_msg(struct rconn *swconn,
     ofpbuf_uninit(&ofpacts);
 }
 
+static struct shash ipv6_prefixd;
+
+enum {
+    PREFIX_SOLICIT,
+    PREFIX_PENDING,
+    PREFIX_DONE,
+};
+
+struct ipv6_prefixd_state {
+    long long int next_announce;
+    struct in6_addr ipv6_addr;
+    struct eth_addr ea;
+    struct eth_addr cmac;
+    int64_t port_key;
+    int64_t metadata;
+    struct in6_addr prefix;
+    unsigned plife_time;
+    unsigned vlife_time;
+    unsigned aid;
+    unsigned t1;
+    unsigned t2;
+    unsigned plen;
+    int state;
+};
+
+static void
+init_ipv6_prefixd(void)
+{
+    shash_init(&ipv6_prefixd);
+}
+
+static void
+destroy_ipv6_prefixd(void)
+{
+    struct shash_node *iter, *next;
+    SHASH_FOR_EACH_SAFE (iter, next, &ipv6_prefixd) {
+        struct ipv6_prefixd_state *pfd = iter->data;
+        free(pfd);
+        shash_delete(&ipv6_prefixd, iter);
+    }
+    shash_destroy(&ipv6_prefixd);
+}
+
 struct buffer_info {
     struct ofpbuf ofpacts;
     ofp_port_t ofp_port;
@@ -972,6 +1033,277 @@  is_dhcp_flags_broadcast(ovs_be16 flags)
     return flags & htons(DHCP_BROADCAST_FLAG);
 }
 
+static void
+pinctrl_parse_dhcpv6_advt(struct rconn *swconn, const struct flow *ip_flow,
+                          struct dp_packet *pkt_in, const struct match *md)
+{
+    struct udp_header *udp_in = dp_packet_l4(pkt_in);
+    size_t dlen = MIN(ntohs(udp_in->udp_len), dp_packet_l4_size(pkt_in));
+    unsigned char *in_dhcpv6_data = (unsigned char *)(udp_in + 1);
+    uint8_t *data, *end = (uint8_t *)udp_in + dlen;
+    int len = 0;
+
+    data = xmalloc(dlen);
+    /* skip DHCPv6 common header */
+    in_dhcpv6_data += 4;
+    while (in_dhcpv6_data < end) {
+        struct dhcpv6_opt_header *in_opt =
+             (struct dhcpv6_opt_header *)in_dhcpv6_data;
+        int opt_len = sizeof *in_opt + ntohs(in_opt->len);
+
+        if (dlen < opt_len + len) {
+            goto out;
+        }
+
+        switch (ntohs(in_opt->code)) {
+        case DHCPV6_OPT_IA_PD: {
+            int orig_len = len, hdr_len = 0, size = sizeof *in_opt + 12;
+
+            memcpy(&data[len], in_opt, size);
+            in_opt = (struct dhcpv6_opt_header *)(in_dhcpv6_data + size);
+            len += size;
+
+            while (size < opt_len) {
+                int flen = sizeof *in_opt + ntohs(in_opt->len);
+
+                if (dlen < flen + len) {
+                    goto out;
+                }
+
+                if (ntohs(in_opt->code) == DHCPV6_OPT_IA_PREFIX) {
+                    memcpy(&data[len], in_opt, flen);
+                    hdr_len += flen;
+                    len += flen;
+                }
+                if (ntohs(in_opt->code) == DHCPV6_OPT_STATUS_CODE) {
+                   struct dhcpv6_opt_status *status;
+
+                   status = (struct dhcpv6_opt_status *)in_opt;
+                   if (ntohs(status->status_code)) {
+                       goto out;
+                   }
+                }
+                size += flen;
+                in_opt = (struct dhcpv6_opt_header *)(in_dhcpv6_data + size);
+            }
+            in_opt = (struct dhcpv6_opt_header *)&data[orig_len];
+            in_opt->len = htons(hdr_len + 12);
+            break;
+        }
+        case DHCPV6_OPT_SERVER_ID_CODE:
+        case DHCPV6_OPT_CLIENT_ID_CODE:
+            memcpy(&data[len], in_opt, opt_len);
+            len += opt_len;
+            break;
+        default:
+            break;
+        }
+        in_dhcpv6_data += opt_len;
+    }
+
+    uint64_t packet_stub[256 / 8];
+    struct dp_packet packet;
+
+    dp_packet_use_stub(&packet, packet_stub, sizeof packet_stub);
+    eth_compose(&packet, ip_flow->dl_src, ip_flow->dl_dst, ETH_TYPE_IPV6,
+                IPV6_HEADER_LEN);
+
+    struct udp_header *udp_h = compose_ipv6(&packet, IPPROTO_UDP,
+                                            &ip_flow->ipv6_dst,
+                                            &ip_flow->ipv6_src, 0, 0, 255,
+                                            len + UDP_HEADER_LEN + 4);
+    udp_h->udp_len = htons(len + UDP_HEADER_LEN + 4);
+    udp_h->udp_csum = 0;
+    packet_set_udp_port(&packet, htons(546), htons(547));
+
+    unsigned char *dhcp_hdr = (unsigned char *)(udp_h + 1);
+    *dhcp_hdr = DHCPV6_MSG_TYPE_REQUEST;
+    memcpy(dhcp_hdr + 4, data, len);
+
+    uint32_t csum = packet_csum_pseudoheader6(dp_packet_l3(&packet));
+    csum = csum_continue(csum, udp_h, dp_packet_size(&packet) -
+                         ((const unsigned char *)udp_h -
+                          (const unsigned char *)dp_packet_eth(&packet)));
+    udp_h->udp_csum = csum_finish(csum);
+    if (!udp_h->udp_csum) {
+        udp_h->udp_csum = htons(0xffff);
+    }
+
+    if (ip_flow->vlans[0].tci & htons(VLAN_CFI)) {
+        eth_push_vlan(&packet, htons(ETH_TYPE_VLAN_8021Q),
+                      ip_flow->vlans[0].tci);
+    }
+
+    uint64_t ofpacts_stub[4096 / 8];
+    struct ofpbuf ofpacts = OFPBUF_STUB_INITIALIZER(ofpacts_stub);
+    enum ofp_version version = rconn_get_version(swconn);
+    put_load(ntohll(md->flow.metadata), MFF_LOG_DATAPATH, 0, 64, &ofpacts);
+    put_load(md->flow.regs[MFF_LOG_INPORT - MFF_REG0], MFF_LOG_OUTPORT,
+             0, 32, &ofpacts);
+    struct ofpact_resubmit *resubmit = ofpact_put_RESUBMIT(&ofpacts);
+    resubmit->in_port = OFPP_CONTROLLER;
+    resubmit->table_id = OFTABLE_REMOTE_OUTPUT;
+
+    struct ofputil_packet_out po = {
+        .packet = dp_packet_data(&packet),
+        .packet_len = dp_packet_size(&packet),
+        .buffer_id = UINT32_MAX,
+        .ofpacts = ofpacts.data,
+        .ofpacts_len = ofpacts.size,
+    };
+    match_set_in_port(&po.flow_metadata, OFPP_CONTROLLER);
+    enum ofputil_protocol proto = ofputil_protocol_from_ofp_version(version);
+    queue_msg(swconn, ofputil_encode_packet_out(&po, proto));
+    dp_packet_uninit(&packet);
+    ofpbuf_uninit(&ofpacts);
+
+out:
+    free(data);
+}
+
+static struct ipv6_prefixd_state *
+pinctrl_find_prefixd_state(const struct flow *ip_flow, unsigned aid)
+{
+    struct shash_node *iter;
+
+    SHASH_FOR_EACH (iter, &ipv6_prefixd) {
+        struct ipv6_prefixd_state *pfd = iter->data;
+        if (IN6_ARE_ADDR_EQUAL(&pfd->ipv6_addr, &ip_flow->ipv6_dst) &&
+            eth_addr_equals(pfd->ea, ip_flow->dl_dst) &&
+            pfd->aid == aid) {
+            return pfd;
+        }
+    }
+    return NULL;
+}
+
+/* Called with in the pinctrl_handler thread context. */
+static void
+notify_pinctrl_main(void)
+{
+    seq_change(pinctrl_main_seq);
+}
+
+static void
+pinctrl_prefixd_state_handler(const struct flow *ip_flow,
+                              struct in6_addr addr, unsigned aid,
+                              char prefix_len, unsigned t1, unsigned t2,
+                              unsigned plife_time, unsigned vlife_time)
+{
+    struct ipv6_prefixd_state *pfd;
+
+    pfd = pinctrl_find_prefixd_state(ip_flow, aid);
+    if (pfd) {
+        pfd->state = PREFIX_PENDING;
+        pfd->plife_time = plife_time;
+        pfd->vlife_time = vlife_time;
+        pfd->plen = prefix_len;
+        pfd->prefix = addr;
+        pfd->t1 = t1;
+        pfd->t2 = t2;
+        notify_pinctrl_main();
+    }
+}
+
+static void
+pinctrl_parse_dhcpv6_reply(struct dp_packet *pkt_in,
+                           const struct flow *ip_flow)
+    OVS_REQUIRES(pinctrl_mutex)
+{
+    struct udp_header *udp_in = dp_packet_l4(pkt_in);
+    unsigned char *in_dhcpv6_data = (unsigned char *)(udp_in + 1);
+    size_t dlen = MIN(ntohs(udp_in->udp_len), dp_packet_l4_size(pkt_in));
+    unsigned t1 = 0, t2 = 0, vlife_time = 0, plife_time = 0;
+    uint8_t *end = (uint8_t *)udp_in + dlen;
+    uint8_t prefix_len = 0;
+    struct in6_addr ipv6;
+    bool status = false;
+    unsigned aid = 0;
+
+    memset(&ipv6, 0, sizeof (struct in6_addr));
+    /* skip DHCPv6 common header */
+    in_dhcpv6_data += 4;
+    while (in_dhcpv6_data < end) {
+        struct dhcpv6_opt_header *in_opt =
+             (struct dhcpv6_opt_header *)in_dhcpv6_data;
+        int opt_len = sizeof *in_opt + ntohs(in_opt->len);
+
+        if (in_dhcpv6_data + opt_len > end) {
+            break;
+        }
+
+        switch (ntohs(in_opt->code)) {
+        case DHCPV6_OPT_IA_PD: {
+            int size = sizeof *in_opt + 12;
+            in_opt = (struct dhcpv6_opt_header *)(in_dhcpv6_data + size);
+            struct dhcpv6_opt_ia_na *ia_na =
+                (struct dhcpv6_opt_ia_na *)in_dhcpv6_data;
+
+            aid = ntohl(ia_na->iaid);
+            t1 = ntohl(ia_na->t1);
+            t2 = ntohl(ia_na->t2);
+            if (t1 > t2 && t2 > 0) {
+                break;
+            }
+
+            while (size < opt_len) {
+                if (ntohs(in_opt->code) == DHCPV6_OPT_IA_PREFIX) {
+                    struct dhcpv6_opt_ia_prefix *ia_hdr =
+                        (struct dhcpv6_opt_ia_prefix *)(in_dhcpv6_data + size);
+
+                    prefix_len = ia_hdr->plen;
+                    plife_time = ntohl(ia_hdr->plife_time);
+                    vlife_time = ntohl(ia_hdr->vlife_time);
+                    memcpy(&ipv6, &ia_hdr->ipv6, sizeof (struct in6_addr));
+                }
+                if (ntohs(in_opt->code) == DHCPV6_OPT_STATUS_CODE) {
+                   struct dhcpv6_opt_status *status_hdr;
+
+                   status_hdr = (struct dhcpv6_opt_status *)in_opt;
+                   status = ntohs(status_hdr->status_code) == 0;
+                }
+                size += sizeof *in_opt + ntohs(in_opt->len);
+                in_opt = (struct dhcpv6_opt_header *)(in_dhcpv6_data + size);
+            }
+            break;
+        }
+        default:
+            break;
+        }
+        in_dhcpv6_data += opt_len;
+    }
+    if (status) {
+        pinctrl_prefixd_state_handler(ip_flow, ipv6, aid, prefix_len,
+                                      t1, t2, plife_time, vlife_time);
+    }
+}
+
+static void
+pinctrl_handle_dhcp6_server(struct rconn *swconn, const struct flow *ip_flow,
+                            struct dp_packet *pkt_in, const struct match *md)
+{
+    if (ip_flow->dl_type != htons(ETH_TYPE_IPV6) ||
+        ip_flow->nw_proto != IPPROTO_UDP) {
+        return;
+    }
+
+    struct udp_header *udp_in = dp_packet_l4(pkt_in);
+    unsigned char *dhcp_hdr = (unsigned char *)(udp_in + 1);
+
+    switch (*dhcp_hdr) {
+    case DHCPV6_MSG_TYPE_ADVT:
+        pinctrl_parse_dhcpv6_advt(swconn, ip_flow, pkt_in, md);
+        break;
+    case DHCPV6_MSG_TYPE_REPLY:
+        ovs_mutex_lock(&pinctrl_mutex);
+        pinctrl_parse_dhcpv6_reply(pkt_in, ip_flow);
+        ovs_mutex_unlock(&pinctrl_mutex);
+        break;
+    default:
+        break;
+    }
+}
+
 /* Called with in the pinctrl_handler thread context. */
 static void
 pinctrl_handle_put_dhcp_opts(
@@ -2012,6 +2344,10 @@  process_packet_in(struct rconn *swconn, const struct ofp_header *msg)
         pinctrl_handle_bind_vport(&pin.flow_metadata.flow, &userdata);
         ovs_mutex_unlock(&pinctrl_mutex);
         break;
+    case ACTION_OPCODE_DHCP6_SERVER:
+        pinctrl_handle_dhcp6_server(swconn, &headers, &packet,
+                                    &pin.flow_metadata);
+        break;
 
     case ACTION_OPCODE_HANDLE_SVC_CHECK:
         ovs_mutex_lock(&pinctrl_mutex);
@@ -2062,13 +2398,6 @@  notify_pinctrl_handler(void)
     seq_change(pinctrl_handler_seq);
 }
 
-/* Called with in the pinctrl_handler thread context. */
-static void
-notify_pinctrl_main(void)
-{
-    seq_change(pinctrl_main_seq);
-}
-
 /* pinctrl_handler pthread function. */
 static void *
 pinctrl_handler(void *arg_)
@@ -2090,6 +2419,7 @@  pinctrl_handler(void *arg_)
     /* Next multicast query (IGMP) in ms. */
     static long long int send_mcast_query_time = LLONG_MAX;
     static long long int svc_monitors_next_run_time = LLONG_MAX;
+    static long long int send_prefixd_time = LLONG_MAX;
 
     swconn = rconn_create(5, 0, DSCP_DEFAULT, 1 << OFP13_VERSION);
 
@@ -2143,6 +2473,7 @@  pinctrl_handler(void *arg_)
                 ovs_mutex_lock(&pinctrl_mutex);
                 send_garp_rarp_run(swconn, &send_garp_rarp_time);
                 send_ipv6_ras(swconn, &send_ipv6_ra_time);
+                send_ipv6_prefixd(swconn, &send_prefixd_time);
                 send_mac_binding_buffered_pkts(swconn);
                 ovs_mutex_unlock(&pinctrl_mutex);
 
@@ -2160,6 +2491,7 @@  pinctrl_handler(void *arg_)
         ipv6_ra_wait(send_ipv6_ra_time);
         ip_mcast_querier_wait(send_mcast_query_time);
         svc_monitors_wait(svc_monitors_next_run_time);
+        ipv6_prefixd_wait(send_prefixd_time);
 
         new_seq = seq_read(pinctrl_handler_seq);
         seq_wait(pinctrl_handler_seq, new_seq);
@@ -2211,6 +2543,8 @@  pinctrl_run(struct ovsdb_idl_txn *ovnsb_idl_txn,
                            sbrec_port_binding_by_name, br_int, chassis,
                            local_datapaths, active_tunnels);
     prepare_ipv6_ras(local_datapaths);
+    prepare_ipv6_prefixd(ovnsb_idl_txn, sbrec_port_binding_by_name,
+                         local_datapaths, chassis, active_tunnels);
     sync_dns_cache(dns_table);
     controller_event_run(ovnsb_idl_txn, ce_table, chassis);
     ip_mcast_sync(ovnsb_idl_txn, chassis, local_datapaths,
@@ -2658,6 +2992,169 @@  send_ipv6_ras(struct rconn *swconn, long long int *send_ipv6_ra_time)
     }
 }
 
+static void
+compose_prefixd_solicit(struct dp_packet *b,
+                        struct ipv6_prefixd_state *pfd,
+                        const struct eth_addr eth_dst,
+                        const struct in6_addr *ipv6_dst)
+{
+    eth_compose(b, eth_dst, pfd->ea, ETH_TYPE_IPV6, IPV6_HEADER_LEN);
+
+    int payload = sizeof(struct dhcpv6_opt_server_id) +
+                  sizeof(struct dhcpv6_opt_ia_na);
+    if (ipv6_addr_is_set(&pfd->prefix)) {
+        payload += sizeof(struct dhcpv6_opt_ia_prefix);
+    }
+    int len = UDP_HEADER_LEN + 4 + payload;
+    struct udp_header *udp_h = compose_ipv6(b, IPPROTO_UDP, &pfd->ipv6_addr,
+                                            ipv6_dst, 0, 0, 255, len);
+    udp_h->udp_len = htons(len);
+    udp_h->udp_csum = 0;
+    packet_set_udp_port(b, htons(546), htons(547));
+
+    unsigned char *dhcp_hdr = (unsigned char *)(udp_h + 1);
+    *dhcp_hdr = DHCPV6_MSG_TYPE_SOLICIT;
+
+    struct dhcpv6_opt_server_id *opt_client_id =
+        (struct dhcpv6_opt_server_id *)(dhcp_hdr + 4);
+    opt_client_id->opt.code = htons(DHCPV6_OPT_CLIENT_ID_CODE);
+    opt_client_id->opt.len = htons(sizeof(struct dhcpv6_opt_server_id) -
+                                   sizeof(struct dhcpv6_opt_header));
+    opt_client_id->duid_type = htons(DHCPV6_DUID_LL);
+    opt_client_id->hw_type = htons(DHCPV6_HW_TYPE_ETH);
+    opt_client_id->mac = pfd->cmac;
+
+    if (!ipv6_addr_is_set(&pfd->prefix)) {
+        pfd->aid = random_uint32();
+    }
+    struct dhcpv6_opt_ia_na *ia_pd =
+            (struct dhcpv6_opt_ia_na *)(opt_client_id + 1);
+    ia_pd->opt.code = htons(DHCPV6_OPT_IA_PD);
+    int opt_len = sizeof(struct dhcpv6_opt_ia_na) -
+                  sizeof(struct dhcpv6_opt_header);
+    if (ipv6_addr_is_set(&pfd->prefix)) {
+        opt_len += sizeof(struct dhcpv6_opt_ia_prefix);
+    }
+    ia_pd->opt.len = htons(opt_len);
+    ia_pd->iaid = htonl(pfd->aid);
+    ia_pd->t1 = OVS_BE32_MAX;
+    ia_pd->t2 = OVS_BE32_MAX;
+    if (ipv6_addr_is_set(&pfd->prefix)) {
+        struct dhcpv6_opt_ia_prefix *ia_prefix =
+            (struct dhcpv6_opt_ia_prefix *)(ia_pd + 1);
+        ia_prefix->opt.code = htons(DHCPV6_OPT_IA_PREFIX);
+        ia_prefix->opt.len = htons(sizeof(struct dhcpv6_opt_ia_prefix) -
+                                   sizeof(struct dhcpv6_opt_header));
+        ia_prefix->plife_time = OVS_BE32_MAX;
+        ia_prefix->vlife_time = OVS_BE32_MAX;
+        ia_prefix->plen = pfd->plen;
+        ia_prefix->ipv6 = pfd->prefix;
+    }
+
+    uint32_t csum = packet_csum_pseudoheader6(dp_packet_l3(b));
+    csum = csum_continue(csum, udp_h, dp_packet_size(b) -
+                         ((const unsigned char *)udp_h -
+                          (const unsigned char *)dp_packet_eth(b)));
+    udp_h->udp_csum = csum_finish(csum);
+    if (!udp_h->udp_csum) {
+        udp_h->udp_csum = htons(0xffff);
+    }
+}
+
+#define IPV6_PREFIXD_TIMEOUT    3000LL
+static long long int
+ipv6_prefixd_send(struct rconn *swconn, struct ipv6_prefixd_state *pfd)
+{
+    long long int cur_time = time_msec();
+    if (cur_time < pfd->next_announce) {
+        return pfd->next_announce;
+    }
+
+    uint64_t packet_stub[256 / 8];
+    struct dp_packet packet;
+
+    struct eth_addr eth_dst;
+    eth_dst = (struct eth_addr) ETH_ADDR_C(33,33,00,01,00,02);
+    struct in6_addr ipv6_dst;
+    ipv6_parse("ff02::1:2", &ipv6_dst);
+
+    dp_packet_use_stub(&packet, packet_stub, sizeof packet_stub);
+    compose_prefixd_solicit(&packet, pfd, eth_dst, &ipv6_dst);
+
+    uint64_t ofpacts_stub[4096 / 8];
+    struct ofpbuf ofpacts = OFPBUF_STUB_INITIALIZER(ofpacts_stub);
+
+    /* Set MFF_LOG_DATAPATH and MFF_LOG_INPORT. */
+    uint32_t dp_key = pfd->metadata;
+    uint32_t port_key = pfd->port_key;
+    put_load(dp_key, MFF_LOG_DATAPATH, 0, 64, &ofpacts);
+    put_load(port_key, MFF_LOG_INPORT, 0, 32, &ofpacts);
+    put_load(1, MFF_LOG_FLAGS, MLF_LOCAL_ONLY_BIT, 1, &ofpacts);
+    struct ofpact_resubmit *resubmit = ofpact_put_RESUBMIT(&ofpacts);
+    resubmit->in_port = OFPP_CONTROLLER;
+    resubmit->table_id = OFTABLE_LOG_INGRESS_PIPELINE;
+
+    struct ofputil_packet_out po = {
+        .packet = dp_packet_data(&packet),
+        .packet_len = dp_packet_size(&packet),
+        .buffer_id = UINT32_MAX,
+        .ofpacts = ofpacts.data,
+        .ofpacts_len = ofpacts.size,
+    };
+
+    match_set_in_port(&po.flow_metadata, OFPP_CONTROLLER);
+    enum ofp_version version = rconn_get_version(swconn);
+    enum ofputil_protocol proto = ofputil_protocol_from_ofp_version(version);
+    queue_msg(swconn, ofputil_encode_packet_out(&po, proto));
+    dp_packet_uninit(&packet);
+    ofpbuf_uninit(&ofpacts);
+    pfd->next_announce = cur_time + random_range(IPV6_PREFIXD_TIMEOUT);
+
+    return pfd->next_announce;
+}
+
+static bool ipv6_prefixd_should_inject(void)
+{
+    struct shash_node *iter;
+
+    SHASH_FOR_EACH (iter, &ipv6_prefixd) {
+        struct ipv6_prefixd_state *pfd = iter->data;
+        if (pfd->state == PREFIX_SOLICIT) {
+            return true;
+        }
+        if (pfd->state == PREFIX_DONE &&
+            pfd->next_announce < time_msec()) {
+            pfd->state = PREFIX_SOLICIT;
+            return true;
+        }
+    }
+    return false;
+}
+
+static void
+ipv6_prefixd_wait(long long int timeout)
+{
+    if (ipv6_prefixd_should_inject()) {
+        poll_timer_wait_until(timeout);
+    }
+}
+
+static void
+send_ipv6_prefixd(struct rconn *swconn, long long int *send_prefixd_time)
+    OVS_REQUIRES(pinctrl_mutex)
+{
+    struct shash_node *iter;
+
+    *send_prefixd_time = LLONG_MAX;
+    SHASH_FOR_EACH (iter, &ipv6_prefixd) {
+        struct ipv6_prefixd_state *pfd = iter->data;
+        long long int next_msg = ipv6_prefixd_send(swconn, pfd);
+        if (*send_prefixd_time > next_msg) {
+            *send_prefixd_time = next_msg;
+        }
+    }
+}
+
 /* Called by pinctrl_run(). Runs with in the main ovn-controller
  * thread context. */
 static void
@@ -2735,6 +3232,152 @@  prepare_ipv6_ras(const struct hmap *local_datapaths)
 
 }
 
+static bool
+fill_ipv6_prefix_state(struct ovsdb_idl_txn *ovnsb_idl_txn,
+                       const struct local_datapath *ld,
+                       struct eth_addr ea, struct in6_addr ipv6_addr,
+                       int64_t tunnel_key, int64_t dp_tunnel_key)
+    OVS_REQUIRES(pinctrl_mutex)
+{
+    bool changed = false;
+
+    for (size_t i = 0; i < ld->n_peer_ports; i++) {
+        const struct sbrec_port_binding *pb = ld->peer_ports[i].local;
+
+        if (!smap_get_bool(&pb->options, "ipv6_prefix", false)) {
+            continue;
+        }
+
+        struct lport_addresses c_addrs;
+        for (size_t j = 0; j < pb->n_mac; j++) {
+            if (extract_lsp_addresses(pb->mac[j], &c_addrs)) {
+                    break;
+            }
+        }
+
+        struct ipv6_prefixd_state *pfd = shash_find_data(
+                &ipv6_prefixd, pb->logical_port);
+        if (!pfd) {
+            pfd = xzalloc(sizeof *pfd);
+            pfd->ipv6_addr = ipv6_addr;
+            pfd->ea = ea;
+            pfd->cmac = c_addrs.ea;
+            pfd->metadata = dp_tunnel_key;
+            pfd->port_key = tunnel_key;
+            shash_add(&ipv6_prefixd, pb->logical_port, pfd);
+            pfd->next_announce = time_msec() +
+                                 random_range(IPV6_PREFIXD_TIMEOUT);
+            changed = true;
+
+            char prefix_s[IPV6_SCAN_LEN + 6];
+            const char *ipv6_pd_list = smap_get(&pb->options,
+                                                "ipv6_ra_pd_list");
+            if (!ipv6_pd_list ||
+                !ovs_scan(ipv6_pd_list, "%u:%s/%d",
+                          &pfd->aid, prefix_s, &pfd->plen) ||
+                ipv6_parse(prefix_s, &pfd->prefix)) {
+                pfd->prefix = in6addr_any;
+            }
+        } else if (pfd->state == PREFIX_PENDING && ovnsb_idl_txn) {
+            char prefix_str[INET6_ADDRSTRLEN + 1] = {};
+            struct smap options;
+
+            pfd->state = PREFIX_DONE;
+            pfd->next_announce = time_msec() + pfd->t1 * 1000;
+            ipv6_string_mapped(prefix_str, &pfd->prefix);
+            smap_clone(&options, &pb->options);
+            smap_add_format(&options, "ipv6_ra_pd_list", "%d:%s/%d",
+                            pfd->aid, prefix_str, pfd->plen);
+            sbrec_port_binding_set_options(pb, &options);
+            smap_destroy(&options);
+        }
+    }
+
+    return changed;
+}
+
+static void
+prepare_ipv6_prefixd(struct ovsdb_idl_txn *ovnsb_idl_txn,
+                     struct ovsdb_idl_index *sbrec_port_binding_by_name,
+                     const struct hmap *local_datapaths,
+                     const struct sbrec_chassis *chassis,
+                     const struct sset *active_tunnels)
+    OVS_REQUIRES(pinctrl_mutex)
+{
+    const struct local_datapath *ld;
+    bool changed = false;
+
+    HMAP_FOR_EACH (ld, hmap_node, local_datapaths) {
+        if (!smap_get(&ld->datapath->external_ids, "logical-router")) {
+            /* logical switch */
+            continue;
+        }
+
+        for (size_t i = 0; i < ld->n_peer_ports; i++) {
+            const struct sbrec_port_binding *pb = ld->peer_ports[i].local;
+            int j;
+
+            if (!smap_get_bool(&pb->options, "ipv6_prefix_delegation",
+                               false)) {
+                continue;
+            }
+
+            const char *peer_s = smap_get(&pb->options, "peer");
+            if (!peer_s) {
+                continue;
+            }
+
+            const struct sbrec_port_binding *peer
+                = lport_lookup_by_name(sbrec_port_binding_by_name, peer_s);
+            if (!peer) {
+                continue;
+            }
+
+            char *redirect_name = xasprintf("cr-%s", pb->logical_port);
+            bool resident = lport_is_chassis_resident(
+                    sbrec_port_binding_by_name, chassis, active_tunnels,
+                    redirect_name);
+            free(redirect_name);
+            if (!resident && strcmp(pb->type, "l3gateway")) {
+                continue;
+            }
+
+            struct in6_addr ip6_addr;
+            struct eth_addr ea;
+            for (j = 0; j < pb->n_mac; j++) {
+                struct lport_addresses laddrs;
+
+                if (!extract_lsp_addresses(pb->mac[j], &laddrs)) {
+                    continue;
+                }
+
+                ea = laddrs.ea;
+                if (laddrs.n_ipv6_addrs > 0) {
+                    ip6_addr = laddrs.ipv6_addrs[0].addr;
+                    break;
+                }
+            }
+
+            if (eth_addr_is_zero(ea)) {
+                continue;
+            }
+
+            if (j == pb->n_mac) {
+                in6_generate_lla(ea, &ip6_addr);
+            }
+
+            changed |= fill_ipv6_prefix_state(ovnsb_idl_txn, ld,
+                                              ea, ip6_addr,
+                                              peer->tunnel_key,
+                                              peer->datapath->tunnel_key);
+        }
+    }
+
+    if (changed) {
+        notify_pinctrl_handler();
+    }
+}
+
 /* Called by pinctrl_run(). Runs with in the main ovn-controller
  * thread context. */
 void
@@ -2757,6 +3400,7 @@  pinctrl_destroy(void)
     free(pinctrl.br_int_name);
     destroy_send_garps_rarps();
     destroy_ipv6_ras();
+    destroy_ipv6_prefixd();
     destroy_buffered_packets_map();
     event_table_destroy();
     destroy_put_mac_bindings();
@@ -4471,6 +5115,7 @@  may_inject_pkts(void)
 {
     return (!shash_is_empty(&ipv6_ras) ||
             !shash_is_empty(&send_garp_rarp_data) ||
+            ipv6_prefixd_should_inject() ||
             !ovs_list_is_empty(&mcast_query_list) ||
             !ovs_list_is_empty(&buffered_mac_bindings));
 }
diff --git a/controller/pinctrl.h b/controller/pinctrl.h
index 8fa4baae9..b76d1b5ca 100644
--- a/controller/pinctrl.h
+++ b/controller/pinctrl.h
@@ -26,6 +26,7 @@  struct hmap;
 struct lport_index;
 struct ovsdb_idl_index;
 struct ovsdb_idl_txn;
+struct ovsdb_idl;
 struct ovsrec_bridge;
 struct sbrec_chassis;
 struct sbrec_dns_table;
diff --git a/include/ovn/actions.h b/include/ovn/actions.h
index 9b014925b..e3dec99b2 100644
--- a/include/ovn/actions.h
+++ b/include/ovn/actions.h
@@ -91,7 +91,8 @@  struct ovn_extend_table;
     OVNACT(TRIGGER_EVENT,     ovnact_controller_event) \
     OVNACT(BIND_VPORT,        ovnact_bind_vport)       \
     OVNACT(HANDLE_SVC_CHECK,  ovnact_handle_svc_check) \
-    OVNACT(FWD_GROUP,         ovnact_fwd_group)
+    OVNACT(FWD_GROUP,         ovnact_fwd_group)       \
+    OVNACT(DHCP6_REPLY,       ovnact_null)
 
 /* enum ovnact_type, with a member OVNACT_<ENUM> for each action. */
 enum OVS_PACKED_ENUM ovnact_type {
@@ -577,6 +578,11 @@  enum action_opcode {
      *     MFF_LOG_INPORT = port
      */
     ACTION_OPCODE_HANDLE_SVC_CHECK,
+    /* handle_dhcpv6_reply { ...actions ...}."
+     *
+     *  The actions, in OpenFlow 1.3 format, follow the action_header.
+     */
+    ACTION_OPCODE_DHCP6_SERVER,
 };
 
 /* Header. */
diff --git a/lib/actions.c b/lib/actions.c
index f22acddff..e64b16bf0 100644
--- a/lib/actions.c
+++ b/lib/actions.c
@@ -2311,6 +2311,20 @@  ovnact_put_opts_free(struct ovnact_put_opts *pdo)
     free_gen_options(pdo->options, pdo->n_options);
 }
 
+static void
+format_DHCP6_REPLY(const struct ovnact_null *a OVS_UNUSED, struct ds *s)
+{
+    ds_put_cstr(s, "handle_dhcpv6_reply;");
+}
+
+static void
+encode_DHCP6_REPLY(const struct ovnact_null *a OVS_UNUSED,
+                   const struct ovnact_encode_params *ep OVS_UNUSED,
+                   struct ofpbuf *ofpacts)
+{
+    encode_controller_op(ACTION_OPCODE_DHCP6_SERVER, ofpacts);
+}
+
 static void
 parse_SET_QUEUE(struct action_context *ctx)
 {
@@ -3258,6 +3272,8 @@  parse_action(struct action_context *ctx)
         parse_handle_svc_check(ctx);
     } else if (lexer_match_id(ctx->lexer, "fwd_group")) {
         parse_fwd_group_action(ctx);
+    } else if (lexer_match_id(ctx->lexer, "handle_dhcpv6_reply")) {
+        ovnact_put_DHCP6_REPLY(ctx->ovnacts);
     } else {
         lexer_syntax_error(ctx->lexer, "expecting action");
     }
diff --git a/lib/ovn-l7.h b/lib/ovn-l7.h
index 931e6ffcf..cbea2a0c8 100644
--- a/lib/ovn-l7.h
+++ b/lib/ovn-l7.h
@@ -178,8 +178,11 @@  struct dhcp_opt6_header {
 #define DHCPV6_OPT_SERVER_ID_CODE        2
 #define DHCPV6_OPT_IA_NA_CODE            3
 #define DHCPV6_OPT_IA_ADDR_CODE          5
+#define DHCPV6_OPT_STATUS_CODE           13
 #define DHCPV6_OPT_DNS_SERVER_CODE       23
 #define DHCPV6_OPT_DOMAIN_SEARCH_CODE    24
+#define DHCPV6_OPT_IA_PD                 25
+#define DHCPV6_OPT_IA_PREFIX             26
 
 #define DHCPV6_OPT_SERVER_ID \
     DHCP_OPTION("server_id", DHCPV6_OPT_SERVER_ID_CODE, "mac")
@@ -258,6 +261,22 @@  struct ovs_nd_route_info {
 };
 BUILD_ASSERT_DECL(ND_ROUTE_INFO_OPT_LEN == sizeof(struct ovs_nd_route_info));
 
+OVS_PACKED(
+struct dhcpv6_opt_ia_prefix {
+    struct dhcpv6_opt_header opt;
+    ovs_be32 plife_time;
+    ovs_be32 vlife_time;
+    uint8_t plen;
+    struct in6_addr ipv6;
+});
+
+OVS_PACKED(
+struct dhcpv6_opt_status {
+    struct dhcpv6_opt_header opt;
+    ovs_be16 status_code;
+    uint8_t msg[];
+});
+
 #define DHCPV6_DUID_LL      3
 #define DHCPV6_HW_TYPE_ETH  1
 
diff --git a/ovn-sb.xml b/ovn-sb.xml
index 3ae9d4f92..72466b97e 100644
--- a/ovn-sb.xml
+++ b/ovn-sb.xml
@@ -2149,6 +2149,17 @@  tcp.flags = RST;
           <p><b>Example:</b> <code>handle_svc_check(inport);</code></p>
         </dd>
 
+        <dt><code>handle_dhcpv6_reply;</code></dt>
+        <dd>
+          <p>
+            Handle DHCPv6 prefix delegation advertisements/replies from
+            a IPv6 delegation server. <code>ovn-controller</code> will
+            add an entry <code>ipv6_ra_pd_list</code> in the
+            <ref table="Port_Binding" column="options"/> table for each
+            prefix received from the delegation server
+          </p>
+        </dd>
+
         <dt><code><var>R</var> = select(<var>N1</var>[=<var>W1</var>], <var>N2</var>[=<var>W2</var>], ...);</code></dt>
         <dd>
           <p>
@@ -2182,6 +2193,13 @@  tcp.flags = RST;
           </p>
         </dd>
 
+        <dt><code>handle_dhcpv6_reply;</code></dt>
+        <dd>
+          <p>
+            This action is used to parse DHCPv6 replies from IPv6
+            Delegation Router and managed IPv6 Prefix delegation state machine
+          </p>
+        </dd>
       </dl>
     </column>
 
diff --git a/tests/ovn.at b/tests/ovn.at
index 8cdbad743..8a607f1a1 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -1525,6 +1525,10 @@  fwd_group();
 fwd_group(liveness="false", childports="eth0", "lsp1");
     Syntax error at `"false"' expecting `,'.
 
+# prefix delegation
+handle_dhcpv6_reply;
+    encodes as controller(userdata=00.00.00.13.00.00.00.00)
+
 # Miscellaneous negative tests.
 ;
     Syntax error at `;'.
diff --git a/utilities/ovn-trace.c b/utilities/ovn-trace.c
index 84e5f2b5c..e59698ec4 100644
--- a/utilities/ovn-trace.c
+++ b/utilities/ovn-trace.c
@@ -2292,6 +2292,8 @@  trace_actions(const struct ovnact *ovnacts, size_t ovnacts_len,
 
         case OVNACT_FWD_GROUP:
             break;
+        case OVNACT_DHCP6_REPLY:
+            break;
         }
     }
     ds_destroy(&s);