Add support for Ethernet RA dns configuration

Add interface to include default route to RA messages
Add interface to include DNS server address in RA Messages
Add interface to include DNS search list in RA messages

Add parsing of DNS information from RA

Author: Mika

nanostack/net_ipv6_api.h

@@ -131,4 +131,50 @@ int8_t arm_nwk_ipv6_opaque_iid_key(const void *secret_key, uint8_t key_len);
  */
 int8_t arm_nwk_ipv6_opaque_iid_enable(int8_t interface_id, bool enable);
 
+/**
+ * \brief Enable/disable default route in Router advertisements
+ *
+ * Enable or disable RFC 4861 Default router configuration in router advertisements.
+ * This makes the device a default router in the interface.
+ *
+ * \param interface_id Interface ID.
+ * \param enable True to enable.
+ * \return 0 enabled/disabled OK.
+ * \return <0 failed (for example invalid interface ID).
+ *
+ */
+int8_t arm_nwk_ipv6_default_route_enable(int8_t interface_id, bool enable);
+
+/**
+ * \brief add Recursive DNS Server Option information to Router advertisements
+ *
+ * Add Recursive DNS Server Option from RFC 8106 to router advertisements.
+ * This makes it possible to configure DNS server address to other devices connected to the interface.
+ *
+ * \param interface_id Interface ID.
+ * \param address 16 byte array for IPv6 address.
+ * \param lifetime advertised lifetime of the entry. 0 to delete address.
+ * \return 0 DNS server option option successful.
+ * \return <0 failed (for example invalid interface ID).
+ *
+ */
+int8_t arm_nwk_ipv6_dns_server_add(int8_t interface_id, uint8_t *address, uint32_t lifetime);
+
+/**
+ * \brief add DNS Search List Option information to Router advertisements
+ *
+ * Add DNS Search List Option from RFC 8106 to router advertisements.
+ * This makes it possible to configure DNS search list to other devices connected to the interface.
+ *
+ * \param interface_id Interface ID.
+ * \param data byte array encoded following https://tools.ietf.org/html/rfc1035#section-3.1.
+ * \param data_len Length of the byte array
+ * \param lifetime advertised lifetime of the entry. 0 to delete address.
+ * \return 0 DNS server option option successful.
+ * \return <0 failed (for example invalid interface ID).
+ *
+ */
+int8_t arm_nwk_ipv6_dns_search_list_add(int8_t interface_id, uint8_t *data, uint16_t data_len, uint32_t lifetime);
+
+
 #endif /* NET_IPV6_API_H_ */

source/Common_Protocols/icmpv6.c

@@ -859,6 +859,40 @@ static buffer_t *icmpv6_ra_handler(buffer_t *buf)
             } else {
                 ipv6_route_delete(prefix_ptr, prefix_length, cur->id, buf->src_sa.address, ROUTE_RADV);
             }
+        } else if (type == ICMPV6_OPT_DNS_SEARCH_LIST) {
+
+            if (length < 8) {
+                tr_warn("Invalid RA DNS search list opt corrupt");
+                goto next_option; // invalid not accepted
+            }
+            uint32_t dns_lifetime = common_read_32_bit(dptr + 2); // 2 x reserved
+            uint8_t *dns_search_list = dptr + 6;
+            uint8_t dns_search_list_len = length - 8; // Length includes type and length
+
+            tr_info("DNS Search List: %s Lifetime: %lu", trace_array(dns_search_list, dns_search_list_len), (unsigned long) dns_lifetime);
+            // TODO Add DNS server to DNS information storage.
+            // dns_search_list_storage(cur, buf->src_sa.address, dns_search_list, dns_search_list_len, dns_lifetime);
+            (void)dns_search_list;
+            (void)dns_search_list_len;
+            (void)dns_lifetime;
+
+        } else if (type == ICMPV6_OPT_RECURSIVE_DNS_SERVER) {
+            uint8_t dns_length = length / 8;
+
+            if (dns_length < 3) {
+                tr_warn("Invalid RA DNS server opt corrupt");
+                goto next_option; // invalid not accepted
+            }
+            uint8_t dns_count = (dns_length - 1) / 2;
+            uint32_t dns_lifetime = common_read_32_bit(dptr + 2); // 2 x reserved
+            for (int n = 0; n < dns_count; n++) {
+                uint8_t *dns_srv_addr = dptr + 6 + n * 16;
+                tr_info("DNS Server: %s Lifetime: %lu", trace_ipv6(dns_srv_addr), (unsigned long) dns_lifetime);
+                // TODO Add DNS server to DNS information storage.
+                // dns_server_storage(cur, buf->src_sa.address, dns_srv_addr, dns_lifetime);
+                (void)dns_srv_addr;
+                (void)dns_lifetime;
+            }
         } else if (type == ICMPV6_OPT_6LOWPAN_CONTEXT) {
             nd_ra_process_lowpan_context_option(cur, dptr - 2);
         }

source/Common_Protocols/icmpv6.h

@@ -77,6 +77,8 @@
 #define ICMPV6_OPT_REDIRECTED_HDR                   4
 #define ICMPV6_OPT_MTU                              5
 #define ICMPV6_OPT_ROUTE_INFO                       24
+#define ICMPV6_OPT_RECURSIVE_DNS_SERVER             25
+#define ICMPV6_OPT_DNS_SEARCH_LIST                  31
 #define ICMPV6_OPT_ADDR_REGISTRATION                33
 #define ICMPV6_OPT_6LOWPAN_CONTEXT                  34
 #define ICMPV6_OPT_AUTHORITATIVE_BORDER_RTR         35

source/ipv6_stack/protocol_ipv6.c

@@ -57,6 +57,11 @@ typedef struct ipv6_interface_route_on_link_t {
     ns_list_link_t                      link;
 } ipv6_interface_route_on_link_t;
 
+typedef struct ipv6_interface_dns_server_on_link_t {
+    uint8_t                             addr[16];                 /*!< DNS Server IPv6 address */
+    ns_list_link_t                      link;
+} ipv6_interface_dns_server_on_link_t;
+
 #define WB_UPDATE_PERIOD_SECONDS            23
 
 #define ROUTER_SOL_MAX_COUNTER              4
@@ -77,6 +82,14 @@ static NS_LIST_DEFINE(prefix_on_link, ipv6_interface_prefix_on_link_t, link);
 static NS_LIST_DEFINE(route_on_link, ipv6_interface_route_on_link_t, link);
 static prefix_list_t ipv6_prefixs = NS_LIST_INIT(ipv6_prefixs);
 
+
+/*Router advertisement daemon configurations*/
+static uint16_t radv_default_route_lifetime = 0;
+static NS_LIST_DEFINE(dns_server_list, ipv6_interface_dns_server_on_link_t, link);
+
+static uint16_t dns_search_list_len = 0;
+static uint8_t *dns_search_list_ptr = NULL;
+
 bool tunnel_in_use = false;
 
 static void ethernet_data_conf_cb(const eth_mac_api_t *api, const eth_data_conf_t *data)
@@ -426,6 +439,73 @@ void ipv6_stack_route_advert_update(uint8_t *address, uint8_t prefixLength, uint
     }
 }
 
+void ipv6_stack_route_advert_default_route(struct protocol_interface_info_entry *cur, bool enable)
+{
+    if (enable) {
+        radv_default_route_lifetime = icmpv6_radv_max_rtr_adv_interval(cur) * 2 / 10;
+    } else {
+        radv_default_route_lifetime = 0;
+    }
+}
+
+int8_t ipv6_stack_route_advert_dns_server_add(uint8_t *address)
+{
+
+    if (!address) {
+        return -1;
+    }
+
+    ns_list_foreach(ipv6_interface_dns_server_on_link_t, cur_server, &dns_server_list) {
+        if (memcmp(cur_server->addr, address, 16) == 0) {
+            return 0;
+        }
+    }
+    ipv6_interface_dns_server_on_link_t *new_entry = ns_dyn_mem_alloc(sizeof(ipv6_interface_dns_server_on_link_t));
+    if (!new_entry) {
+        return -1;
+    }
+    memcpy(new_entry->addr, address, 16);
+    ns_list_add_to_end(&dns_server_list, new_entry);
+    return 0;
+}
+
+void ipv6_stack_route_advert_dns_server_delete(uint8_t *address)
+{
+    /* If Address is NULL everything is cleared.
+     * */
+    ns_list_foreach_safe(ipv6_interface_dns_server_on_link_t, cur_server, &dns_server_list) {
+        if (!address || memcmp(cur_server->addr, address, 16) == 0) {
+            ns_list_remove(&dns_server_list, cur_server);
+            ns_dyn_mem_free(cur_server);
+        }
+    }
+}
+
+int8_t ipv6_stack_route_advert_dns_search_list_add(uint8_t *data, uint16_t data_len, uint32_t lifetime)
+{
+
+    if (dns_search_list_ptr) {
+        ns_dyn_mem_free(dns_search_list_ptr);
+        dns_search_list_ptr = NULL;
+        dns_search_list_len = 0;
+    }
+
+    // Check if this is delete operation
+    if (lifetime == 0 || data_len == 0 || data == NULL) {
+        return 0;
+    }
+
+    dns_search_list_len = ((data_len / 8) + 1) * 8; //Should have padding to 8 bytes
+    dns_search_list_ptr = ns_dyn_mem_alloc(dns_search_list_len);
+    if (!dns_search_list_ptr) {
+        return -1;
+    }
+
+    memset(dns_search_list_ptr, 0, dns_search_list_len);
+    memcpy(dns_search_list_ptr, data, data_len);
+    return 0;
+}
+
 void ipv6_prefix_on_link_update(uint8_t *address)
 {
     protocol_interface_info_entry_t *cur = nwk_interface_get_ipv6_ptr();
@@ -630,6 +710,7 @@ int8_t ipv6_interface_down(protocol_interface_info_entry_t *cur)
     icmpv6_prefix_list_free(&ipv6_prefixs);
     ipv6_prefix_online_list_free();
     ipv6_rote_advert_list_free();
+    ipv6_stack_route_advert_dns_server_delete(NULL);
     neighbor_cache_flush(&cur->neigh_cache);
     ipv6_route_table_remove_interface(cur->id);
     protocol_core_interface_info_reset(cur);
@@ -661,6 +742,12 @@ void ipv6_nd_ra_advert(protocol_interface_info_entry_t *cur, const uint8_t *dest
     uint16_t length = 12 + 8 + 16;
     length += 32 * ns_list_count(&ipv6_prefixs);
     length += 32 * ns_list_count(&prefix_on_link);
+    if (ns_list_count(&dns_server_list)) {
+        length += 8 + 16 * ns_list_count(&dns_server_list);
+    }
+    if (dns_search_list_len) {
+        length += 8 + dns_search_list_len;
+    }
 
     ns_list_foreach(ipv6_interface_route_on_link_t, tmp_route, &route_on_link) {
         if (tmp_route->prefix_len < 65) {
@@ -680,7 +767,7 @@ void ipv6_nd_ra_advert(protocol_interface_info_entry_t *cur, const uint8_t *dest
         *ptr++ = cur->adv_cur_hop_limit;
         *ptr++ = cur->rtr_adv_flags;
         //Do not advertise default route: set Router Lifetime to 0
-        ptr = common_write_16_bit(0, ptr);
+        ptr = common_write_16_bit(radv_default_route_lifetime, ptr);
         ptr = common_write_32_bit(cur->adv_reachable_time, ptr);
         ptr = common_write_32_bit(cur->adv_retrans_timer, ptr);
 
@@ -749,6 +836,34 @@ void ipv6_nd_ra_advert(protocol_interface_info_entry_t *cur, const uint8_t *dest
             }
         }
 
+        if (ns_list_count(&dns_server_list)) {
+            *ptr++ = ICMPV6_OPT_RECURSIVE_DNS_SERVER;
+            *ptr++ = 1 + 2 * ns_list_count(&dns_server_list); // length is multiples of 8
+            *ptr++ = 0; // Reserved
+            *ptr++ = 0; // Reserved
+            /* RFC8106 The value of Lifetime SHOULD by default be at least 3 * MaxRtrAdvInterval
+             *
+             * Lifetimes are short so we dont support removing entries by setting the lifetime 0
+             * Lifetime is also for all entries so no maintenance is possible
+             */
+            ptr = common_write_32_bit(icmpv6_radv_max_rtr_adv_interval(cur) * 3 / 10, ptr);
+
+            ns_list_foreach_safe(ipv6_interface_dns_server_on_link_t, dns, &dns_server_list) {
+                memcpy(ptr, dns->addr, 16);
+                ptr += 16;
+            }
+        }
+
+        if (dns_search_list_ptr && dns_search_list_len > 0) {
+            *ptr++ = ICMPV6_OPT_DNS_SEARCH_LIST;
+            *ptr++ = 1 + dns_search_list_len / 8; // length is multiples of 8
+            *ptr++ = 0; // Reserved
+            *ptr++ = 0; // Reserved
+            ptr = common_write_32_bit(icmpv6_radv_max_rtr_adv_interval(cur) * 3 / 10, ptr);
+            memcpy(ptr, dns_search_list_ptr, dns_search_list_len);
+            ptr += dns_search_list_len;
+        }
+
         buffer_data_end_set(buf, ptr);
         memcpy(buf->dst_sa.address, dest, 16);
         /* Source must be LL address (even if non-LL dest) */

source/ipv6_stack/protocol_ipv6.h

@@ -66,6 +66,10 @@ void ipv6_nd_ra_advert(struct protocol_interface_info_entry *cur, const uint8_t
 void ipv6_interface_slaac_handler(struct protocol_interface_info_entry *cur, const uint8_t *slaacPrefix, uint8_t prefixLen, uint32_t validLifeTime, uint32_t preferredLifeTime);
 void ipv6_stack_route_advert_update(uint8_t *address, uint8_t prefixLength, uint8_t routePrefer);
 void ipv6_stack_route_advert_remove(uint8_t *address, uint8_t prefixLength);
+void ipv6_stack_route_advert_default_route(struct protocol_interface_info_entry *cur, bool enable);
+int8_t ipv6_stack_route_advert_dns_server_add(uint8_t *address);
+void ipv6_stack_route_advert_dns_server_delete(uint8_t *address);
+int8_t ipv6_stack_route_advert_dns_search_list_add(uint8_t *data, uint16_t data_len, uint32_t lifetime);
 void ipv6_prefix_on_link_update(uint8_t *address);
 void ipv6_prefix_on_link_remove(uint8_t *address);
 int8_t ipv6_interface_accept_ra(int8_t interface_id, net_ipv6_accept_ra_e accept_ra);
@@ -77,6 +81,10 @@ int8_t ipv6_interface_accept_ra(int8_t interface_id, net_ipv6_accept_ra_e accept
 #define ipv6_nd_ra_advert(cur, dest) ((void)0)
 #define ipv6_interface_sitelocal_clone(buf) ((void)0)
 #define ipv6_stack_route_advert_remove(address, prefixLength) ((void)0)
+#define ipv6_stack_route_advert_default_route(cur,enable)
+#define ipv6_stack_route_advert_dns_server_add(address)
+#define ipv6_stack_route_advert_dns_server_delete(address)
+#define ipv6_stack_route_advert_dns_search_list_add(data, data_len, lifetime)
 #define ipv6_prefix_on_link_update(address) ((void)0)
 #define ipv6_prefix_on_link_remove(address) ((void)0)
 #define ipv6_stack_route_advert_update(address, prefixLength, routePrefer) ((void)0)

source/libNET/src/net_ipv6.c

@@ -25,6 +25,7 @@
 #include "Common_Protocols/ipv6_flow.h"
 #include "Common_Protocols/ipv6_fragmentation.h"
 #include "NWK_INTERFACE/Include/protocol.h"
+#include "ipv6_stack/protocol_ipv6.h"
 
 #include "net_ipv6_api.h"
 
@@ -73,3 +74,59 @@ int8_t arm_nwk_ipv6_opaque_iid_enable(int8_t interface_id, bool enable)
     cur->opaque_slaac_iids = enable;
     return 0;
 }
+
+int8_t arm_nwk_ipv6_default_route_enable(int8_t interface_id, bool enable)
+{
+#ifdef HAVE_ETHERNET
+    protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
+    if (!cur) {
+        return -1;
+    }
+
+    ipv6_stack_route_advert_default_route(cur, enable);
+    return 0;
+#else
+    (void)interface_id;
+    (void)enable;
+    return -1;
+#endif
+}
+
+int8_t arm_nwk_ipv6_dns_server_add(int8_t interface_id, uint8_t *address, uint32_t lifetime)
+{
+#ifdef HAVE_ETHERNET
+    protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
+    if (!cur) {
+        return -1;
+    }
+    if (lifetime == 0) {
+        ipv6_stack_route_advert_dns_server_delete(address);
+    } else {
+        return ipv6_stack_route_advert_dns_server_add(address);
+    }
+
+    return 0;
+#else
+    (void)interface_id;
+    (void)address;
+    (void)lifetime;
+    return -1;
+#endif
+}
+
+int8_t arm_nwk_ipv6_dns_search_list_add(int8_t interface_id, uint8_t *data, uint16_t data_len, uint32_t lifetime)
+{
+#ifdef HAVE_ETHERNET
+    protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
+    if (!cur) {
+        return -1;
+    }
+    return ipv6_stack_route_advert_dns_search_list_add(data, data_len, lifetime);
+#else
+    (void)interface_id;
+    (void)data;
+    (void)data_len;
+    (void)lifetime;
+    return -1;
+#endif
+}

test/nanostack/unittest/libNET/net_ipv6/Makefile

@@ -13,6 +13,7 @@ TEST_SRC_FILES = \
         ../../stub/protocol_core_stub.c \
         ../../stub/ipv6_fragmentation_stub.c \
         ../../stub/ipv6_flow_stub.c \
+        ../../stub/protocol_ipv6_stub.c \
         ../../stub/ipv6_routing_table_stub.c \
         ../../stub/address_stub.c \
 

test/nanostack/unittest/stub/protocol_ipv6_stub.c

@@ -108,6 +108,24 @@ void ipv6_stack_route_advert_update(uint8_t *address, uint8_t prefixLength, uint
 {
 }
 
+void ipv6_stack_route_advert_default_route(struct protocol_interface_info_entry *cur, bool enable)
+{
+}
+
+int8_t ipv6_stack_route_advert_dns_server_add(uint8_t *address)
+{
+    return 0;
+}
+
+void ipv6_stack_route_advert_dns_server_delete(uint8_t *address)
+{
+}
+
+int8_t ipv6_stack_route_advert_dns_search_list_add(uint8_t *data, uint16_t data_len, uint32_t lifetime)
+{
+    return 0;
+}
+
 void ipv6_prefix_on_link_update(uint8_t *address)
 {