tweak Lua script argument passing and add --dhcp-luascript sectino to manpage.

generalising the DHCP option filter code:
don't match options against context tag  when
context->netid.net == NULL, since there's no tag then.

man/dnsmasq.8

@@ -1082,7 +1082,7 @@ If the client provides vendor-class, DNSMASQ_VENDOR_CLASS_ID,
 containing the IANA enterprise id for the class, and
 DNSMASQ_VENDOR_CLASS0..DNSMASQ_VENDOR_CLASSn for the data.
 
-DNSMASQ_DUID containing the DUID of the server: this is the same for
+DNSMASQ_SERVER_DUID containing the DUID of the server: this is the same for
 every call to the script.
 
 DNSMASQ_IAID containing the IAID for the lease. If the lease is a
@@ -1115,8 +1115,43 @@ leases will be called with "del" and others with "old". When dnsmasq
 receives a HUP signal, the script will be invoked for existing leases
 with an "old " event.
 .TP
+.B --dhcp-luascript=<path>
+Specify a script written in Lua, to be run when leases are created,
+destroyed or changed. To use this option, dnsmasq must be compiled
+with the correct support. The Lua interpreter is intialised once, when
+dnsmasq starts, so that global variables persist between lease
+events. The Lua code must define a
+.B lease
+function, and may provide
+.B init
+and
+.B shutdown
+functions, which are called, without arguments when dnsmasq starts up
+and terminates.
+
+The 
+.B lease
+method receives the information detailed in 
+.B --dhcp-script. 
+It gets two arguments, firstly the action, which is a string
+containing, "add", "old" or "del", and secondly a table of tag value
+pairs. The tags mostly correspond to the environment variables
+detailed above, for instance the tag "domain" holds the same data as
+the environment variable DNSMASQ_DOMAIN. There are a few extra tags
+which hold the data supplied as arguments to
+.B --dhcp-script. 
+These are 
+.B mac_address, ip_address
+and 
+.B hostname
+for IPv4, and 
+.B client_duid, ip_address
+and 
+.B hostname
+for IPv6. 
+.TP
 .B --dhcp-scriptuser
-Specify the user as which to run the lease-change script. This defaults to root, but can be changed to another user using this flag. 
+Specify the user as which to run the lease-change script or Lua script. This defaults to root, but can be changed to another user using this flag. 
 .TP 
 .B \-9, --leasefile-ro
 Completely suppress use of the lease database file. The file will not

src/dhcp-common.c

@@ -102,7 +102,7 @@ struct dhcp_netid *option_filter(struct dhcp_netid *tags, struct dhcp_netid *con
     }
 
   /* now flag options which are valid, including the context tags,
-     otherwise valid options are inhibited if we found a higher priotity one above */
+     otherwise valid options are inhibited if we found a higher priority one above */
   if (context_tags)
     {
       struct dhcp_netid *last_tag;

src/dhcp6.c

@@ -408,44 +408,18 @@ struct dhcp_config *find_config6(struct dhcp_config *configs,
 				 unsigned char *duid, int duid_len,
 				 char *hostname)
 {
-  int count, new;
   struct dhcp_config *config; 
-  struct hwaddr_config *conf_addr;
-  unsigned char *hwaddr = NULL; 
-  int duid_type, hw_len = 0, hw_type = 0;
-  
-  if (duid)
-    {  
-      for (config = configs; config; config = config->next)
-	if (config->flags & CONFIG_CLID)
-	  {
-	    if (config->clid_len == duid_len && 
-		memcmp(config->clid, duid, duid_len) == 0 &&
-		is_addr_in_context6(context, config))
-	      return config;
-	  }
       
-      /* DHCPv6 doesn't deal in MAC addresses per-se, but some DUIDs do include
-	 MAC addresses, so we try and parse them out here. Not that there is only one
-	 DUID per host and it's created using any one of the MACs, so this is no
-	 good no good for multihomed hosts. */
-      hwaddr = duid;
-      GETSHORT(duid_type, hwaddr);
-      if (duid_type == 1 || duid_type == 3)
+  if (duid)
+    for (config = configs; config; config = config->next)
+      if (config->flags & CONFIG_CLID)
 	{
-	  GETSHORT(hw_type, hwaddr);
-	  if (duid_type == 1)
-	    hwaddr += 4; /* skip time */
-	  hw_len = duid_len - 8;
-	}
-
-      if (hwaddr)
-	for (config = configs; config; config = config->next)
-	  if (config_has_mac(config, hwaddr, hw_len, hw_type) &&
+	  if (config->clid_len == duid_len && 
+	      memcmp(config->clid, duid, duid_len) == 0 &&
 	      is_addr_in_context6(context, config))
 	    return config;
-    }
-  
+	}
+    
   if (hostname && context)
     for (config = configs; config; config = config->next)
       if ((config->flags & CONFIG_NAME) && 
@@ -453,26 +427,6 @@ struct dhcp_config *find_config6(struct dhcp_config *configs,
           is_addr_in_context6(context, config))
         return config;
 
-  /* use match with fewest wildcard octets */
-  if (hwaddr)
-    {
-       struct dhcp_config *candidate; 
-       
-       for (candidate = NULL, count = 0, config = configs; config; config = config->next)
-	if (is_addr_in_context6(context, config))
-	  for (conf_addr = config->hwaddr; conf_addr; conf_addr = conf_addr->next)
-	    if (conf_addr->wildcard_mask != 0 &&
-		conf_addr->hwaddr_len == hw_len &&  
-		(conf_addr->hwaddr_type == hw_type || conf_addr->hwaddr_type == 0) &&
-		(new = memcmp_masked(conf_addr->hwaddr, hwaddr, hw_len, conf_addr->wildcard_mask)) > count)
-	      {
-		count = new;
-		candidate = config;
-	      }
-      
-      return candidate;
-    }
-  
   return NULL;
 }
 

src/helper.c

@@ -217,18 +217,6 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 		p += sprintf(p, ":");
 	    }
 	}
-#ifdef HAVE_DHCP6
-      else
-	{
-	  /* duid not MAC for IPv6 */
-	  for (p = daemon->dhcp_buff, i = 0; i < data.clid_len; i++)
-	    {
-	      p += sprintf(p, "%.2x", buf[i]);
-	      if (i != data.clid_len - 1) 
-		p += sprintf(p, ":");
-	    } 
-	}
-#endif
        
       /* expiry or length into dhcp_buff2 */
 #ifdef HAVE_BROKEN_RTC
@@ -265,6 +253,14 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	      if (i != daemon->duid_len - 1) 
 		p += sprintf(p, ":");
 	    }
+
+	  /* duid not MAC for IPv6 */
+	  for (p = daemon->dhcp_buff, i = 0; i < data.clid_len; i++)
+	    {
+	      p += sprintf(p, "%.2x", buf[i]);
+	      if (i != data.clid_len - 1) 
+		p += sprintf(p, ":");
+	    } 
 	}
 #endif
 
@@ -302,8 +298,10 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 
 	  if (is6)
 	    {
+	      lua_pushstring(lua, daemon->dhcp_buff);
+	      lua_setfield(lua, -2, "client_duid");
 	      lua_pushstring(lua, daemon->packet);
-	      lua_setfield(lua, -2, "duid");
+	      lua_setfield(lua, -2, "server_duid");
 	      lua_pushstring(lua, daemon->dhcp_buff3);
 	      lua_setfield(lua, -2, "iaid");
 	    }
@@ -364,19 +362,21 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	    }
 	  
 	  buf = grab_extradata_lua(buf, end, "tags");
-	  
+
+	  if (is6)
+	    buf = grab_extradata_lua(buf, end, "relay_address");
+	  else if (data.giaddr.s_addr != 0)
+	    {
+	      lua_pushstring(lua, inet_ntoa(data.giaddr));
+	      lua_setfield(lua, -2, "relay_address");
+	    }
+
 	  for (i = 0; buf; i++)
 	    {
 	      sprintf(daemon->dhcp_buff2, "user_class%i", i);
 	      buf = grab_extradata_lua(buf, end, daemon->dhcp_buff2);
 	    }
  
-	  if (!is6 && data.giaddr.s_addr != 0)
-	    {
-	      lua_pushstring(lua, inet_ntoa(data.giaddr));
-	      lua_setfield(lua, -2, "relay_address");
-	    }
-
 	  if (data.action != ACTION_DEL && data.remaining_time != 0)
 	    {
 	      lua_pushnumber(lua, data.remaining_time);
@@ -442,7 +442,7 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
       if (is6)
 	{
 	  my_setenv("DNSMASQ_IAID", daemon->dhcp_buff3, &err);
-	  my_setenv("DNSMASQ_DUID", daemon->packet, &err);
+	  my_setenv("DNSMASQ_SERVER_DUID", daemon->packet, &err);
 	}
 
       if (!is6 && data.clid_len != 0)
@@ -493,16 +493,15 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 
       if (is6)
 	buf = grab_extradata(buf, end, "DNSMASQ_RELAY_ADDRESS", &err);
-      
+      else if (data.giaddr.s_addr != 0)
+	my_setenv("DNSMASQ_RELAY_ADDRESS", inet_ntoa(data.giaddr), &err); 
+
       for (i = 0; buf; i++)
 	{
 	  sprintf(daemon->dhcp_buff2, "DNSMASQ_USER_CLASS%i", i);
 	  buf = grab_extradata(buf, end, daemon->dhcp_buff2, &err);
 	}
       
-      if (!is6 && data.giaddr.s_addr != 0)
-	my_setenv("DNSMASQ_RELAY_ADDRESS", inet_ntoa(data.giaddr), &err); 
-
       if (data.action != ACTION_DEL && data.remaining_time != 0)
 	{
 	  sprintf(daemon->dhcp_buff2, "%u", data.remaining_time);

src/lease.c

@@ -504,10 +504,9 @@ u64 lease_find_max_addr6(struct dhcp_context *context)
   if (!(context->flags & (CONTEXT_STATIC | CONTEXT_PROXY)))
     for (lease = leases; lease; lease = lease->next)
       {
-#ifdef HAVE_DHCP6
 	if (!(lease->flags & (LEASE_TA | LEASE_NA)))
 	  continue;
-#endif
+
 	if (is_same_net6((struct in6_addr *)lease->hwaddr, &context->start6, 64) &&
 	    addr6part((struct in6_addr *)lease->hwaddr) > addr6part(&context->start6) &&
 	    addr6part((struct in6_addr *)lease->hwaddr) <= addr6part(&context->end6) &&

src/rfc2131.c

@@ -2095,7 +2095,8 @@ static void do_options(struct dhcp_context *context,
   struct dhcp_netid_list *id_list;
 
   /* filter options based on tags, those we want get DHOPT_TAGOK bit set */
-  tagif = option_filter(netid, &context->netid, config_opts);
+  context->netid.next = NULL;
+  tagif = option_filter(netid, context && context->netid.net ? &context->netid : NULL, config_opts);
 	
   /* logging */
   if (option_bool(OPT_LOG_OPTS) && req_options)