Add ra-names SLAAC-hostnames from DHCPv4 option.

src/dnsmasq.c

@@ -106,16 +106,14 @@ int main (int argc, char **argv)
     else
       open("/dev/null", O_RDWR); 
 
-#ifdef HAVE_LINUX_NETWORK
+#ifndef HAVE_LINUX_NETWORK
-  netlink_init();
+#  if !(defined(IP_RECVDSTADDR) && defined(IP_RECVIF) && defined(IP_SENDSRCADDR))
-#elif !(defined(IP_RECVDSTADDR) && \
-	defined(IP_RECVIF) && \
-	defined(IP_SENDSRCADDR))
   if (!option_bool(OPT_NOWILD))
     {
       bind_fallback = 1;
       set_option_bool(OPT_NOWILD);
     }
+#  endif
 #endif
 
 #ifndef HAVE_TFTP
@@ -180,10 +178,25 @@ int main (int argc, char **argv)
   if (daemon->dhcp6)
     dhcp6_init();
 
-  if (daemon->ra_contexts || daemon->dhcp6)
-    join_multicast();
 #  endif
 
+#endif
+
+#ifdef HAVE_LINUX_NETWORK
+  /* After lease_init */
+  netlink_init();
+#endif
+
+#ifdef HAVE_DHCP6
+  /* after netlink_init */
+  if (daemon->ra_contexts || daemon->dhcp6)
+    join_multicast();
+#endif
+
+#ifdef HAVE_DHCP
+  /* after netlink_init */
+  if (daemon->dhcp || daemon->dhcp6)
+    lease_find_interfaces();
 #endif
 
   if (!enumerate_interfaces())
@@ -552,6 +565,8 @@ int main (int argc, char **argv)
 	  my_syslog(MS_DHCP | LOG_INFO, 
 		    (dhcp_tmp->flags & CONTEXT_STATIC) ? 
 		    _("DHCP, static leases only on %.0s%s, lease time %s") :
+		    (dhcp_tmp->flags & CONTEXT_RA_NAME) ? 
+		    _("router advertisement with DHCPv4-derived names on %.0s%s, lifetime %s") :
 		    (dhcp_tmp->flags & CONTEXT_RA_ONLY) ? 
 		    _("router advertisement only on %.0s%s, lifetime %s") :
 		    (dhcp_tmp->flags & CONTEXT_PROXY) ?

src/dnsmasq.h

@@ -621,6 +621,7 @@ struct dhcp_context {
 #define CONTEXT_PROXY     8
 #define CONTEXT_RA_ONLY  16
 #define CONTEXT_RA_DONE  32
+#define CONTEXT_RA_NAME  64
 
 struct ping_result {
   struct in_addr addr;
@@ -629,6 +630,13 @@ struct ping_result {
   struct ping_result *next;
 };
 
+struct subnet_map {
+  int iface;
+  struct in6_addr subnet;
+  struct subnet_map *next;
+};
+  
+  
 struct tftp_file {
   int refcount, fd;
   off_t size;
@@ -948,6 +956,7 @@ void lease_prune(struct dhcp_lease *target, time_t now);
 void lease_update_from_configs(void);
 int do_script_run(time_t now);
 void rerun_scripts(void);
+void lease_find_interfaces(void);
 #ifdef HAVE_SCRIPT
 void lease_add_extradata(struct dhcp_lease *lease, unsigned char *data, 
 			 unsigned int len, int delim);
@@ -1083,4 +1092,5 @@ void ra_init(time_t now);
 void icmp6_packet(void);
 time_t periodic_ra(time_t now);
 void ra_start_unsolicted(time_t now);
+struct subnet_map *build_subnet_map(void);
 #endif

src/lease.c

@@ -340,20 +340,103 @@ void lease_update_file(time_t now)
     alarm((unsigned)difftime(next_event, now)); 
 }
 
-void lease_update_dns(void)
+
+static int find_interface_v4(struct in_addr local, int if_index, 
+			     struct in_addr netmask, struct in_addr broadcast, void *vparam)
 {
   struct dhcp_lease *lease;
   
+  (void) broadcast;
+  (void) vparam;
+
+  for (lease = leases; lease; lease = lease->next)
+    if (!(lease->flags & (LEASE_TA | LEASE_NA)))
+      if (is_same_net(local, lease->addr, netmask))
+	lease->last_interface = if_index;
+  
+  return 1;
+}
+
+#ifdef HAVE_DHCP6
+static int find_interface_v6(struct in6_addr *local,  int prefix,
+			     int scope, int if_index, int dad, void *vparam)
+{
+  struct dhcp_lease *lease;
+  
+  (void) scope;
+  (void) vparam;
+  (void)dad;
+
+  for (lease = leases; lease; lease = lease->next)
+    if ((lease->flags & (LEASE_TA | LEASE_NA)))
+      if (is_same_net6(local, (struct in6_addr *)&lease->hwaddr, prefix))
+	lease->last_interface = if_index;
+  
+  return 1;
+}
+#endif
+
+
+/* Find interfaces associated with leases at start-up. This gets updated as
+   we do DHCP transactions, but information about directly-connected subnets
+   is useful from scrips and necessary for determining SLAAC addresses from
+   start-time. */
+void lease_find_interfaces(void)
+{
+  iface_enumerate(AF_INET, NULL, find_interface_v4);
+#ifdef HAVE_DHCP6
+  iface_enumerate(AF_INET6, NULL, find_interface_v6);
+#endif
+}
+
+
+
+void lease_update_dns(void)
+{
+  struct dhcp_lease *lease;
+
   if (daemon->port != 0 && dns_dirty)
     {
-      cache_unhash_dhcp();
+#ifdef HAVE_DHCP6     
+      struct subnet_map *subnets = build_subnet_map();
+#endif
       
+      cache_unhash_dhcp();
+
       for (lease = leases; lease; lease = lease->next)
 	{
 	  int prot = AF_INET;
+	  
 #ifdef HAVE_DHCP6
 	  if (lease->flags & (LEASE_TA | LEASE_NA))
 	    prot = AF_INET6;
+	  else
+	    {
+	      struct subnet_map *map;
+	      for (map = subnets; map; map = map->next)
+		if (lease->last_interface == map->iface)
+		  {
+		    struct in6_addr addr = map->subnet;
+		    if (lease->hwaddr_len == 6)
+		      {
+			/* convert MAC address to EUI-64 */
+			memcpy(&addr.s6_addr[8], lease->hwaddr, 3);
+			memcpy(&addr.s6_addr[13], &lease->hwaddr[3], 3);
+			addr.s6_addr[11] = 0xff;
+			addr.s6_addr[12] = 0xfe;
+			addr.s6_addr[8] ^= 0x02;
+		      }
+		    else if (lease->hwaddr_len == 8)
+		      memcpy(&addr.s6_addr[8], lease->hwaddr, 8);
+		    else
+		      continue;
+			     
+		    if (lease->fqdn)
+		      cache_add_dhcp_entry(lease->fqdn, AF_INET6, (struct all_addr *)&addr, lease->expires);
+		    if (!option_bool(OPT_DHCP_FQDN) && lease->hostname)
+		      cache_add_dhcp_entry(lease->hostname, AF_INET6, (struct all_addr *)&addr, lease->expires);
+		  }
+	    }
 #endif
 	  
 	  if (lease->fqdn)

src/option.c

@@ -2345,6 +2345,11 @@ static char *one_opt(int option, char *arg, char *gen_prob, int command_line)
 		memcpy(&new->end6, &new->start6, IN6ADDRSZ);
 		new->flags |= CONTEXT_RA_ONLY;
 	      }
+	    else if (strcmp(a[1], "ra-names") == 0)
+	      {
+		memcpy(&new->end6, &new->start6, IN6ADDRSZ);
+		new->flags |= CONTEXT_RA_NAME | CONTEXT_RA_ONLY;
+	      }
 	    else if (!inet_pton(AF_INET6, a[1], &new->end6))
 	      option = '?';
 	    
@@ -2370,7 +2375,9 @@ static char *one_opt(int option, char *arg, char *gen_prob, int command_line)
 		  {
 		    new->prefix = pref;
 		    leasepos = 3;
-		    if (new->prefix < 64)
+		    if ((new->flags & CONTEXT_RA_ONLY) && new->prefix != 64)
+		      problem = _("prefix must be exactly 64 for RA subnets");
+		    else if (new->prefix < 64)
 		      problem = _("prefix must be at least 64");
 		  }
 	      }

src/radv.c

@@ -426,4 +426,69 @@ static int iface_search(struct in6_addr *local,  int prefix,
   return 1; /* keep searching */
 }
 
+static int add_subnet(struct in6_addr *local,  int prefix,
+		      int scope, int if_index, int dad, void *vparam)
+{ 
+  struct dhcp_context *context;
+  struct subnet_map **subnets = vparam;
+  struct subnet_map *map;
+
+  (void)scope;
+  (void)dad;
+
+  for (context = daemon->ra_contexts; context; context = context->next)
+    if ((context->flags & CONTEXT_RA_NAME) &&
+	prefix == context->prefix &&
+	is_same_net6(local, &context->start6, prefix) &&
+	is_same_net6(local, &context->end6, prefix))
+      {
+	for (map = *subnets; map; map = map->next)
+	  if (map->iface == 0)
+	    break;
+	  else if (map->iface == if_index && is_same_net6(local, &map->subnet, prefix))
+	    continue;
+	
+	if (!map && (map = whine_malloc(sizeof(struct subnet_map))))
+	  {
+	    map->next = *subnets;
+	    *subnets = map;
+	  }
+	
+	if (map)
+	  {
+	    map->iface = if_index;
+	    map->subnet = *local;
+	  }
+      }
+
+  return 1;
+}
+
+/* Build a map from ra-names subnets to corresponding interfaces. This
+   is used to go from DHCPv4 leases to SLAAC addresses, 
+   interface->IPv6-subnet, IPv6-subnet + MAC address -> SLAAC.
+*/	      
+struct subnet_map *build_subnet_map(void)
+{
+  struct subnet_map *map;
+  struct dhcp_context *context;
+  static struct subnet_map *subnets = NULL;
+ 
+  for (context = daemon->ra_contexts; context; context = context->next)
+    if ((context->flags & CONTEXT_RA_NAME))
+      break;
+
+  if (!context)
+    return NULL;
+
+  /* mark unused */
+  for (map = subnets; map; map = map->next)
+    map->iface = 0;
+
+  if (iface_enumerate(AF_INET6, &subnets, add_subnet))
+    return subnets;
+  
+  return NULL;
+}
+
 #endif