Send "FTP transfer complete" events to the DHCP lease script.

CHANGELOG

@@ -24,6 +24,24 @@ version 2.61
 	    Add --host-record. Thanks to Rob Zwissler for the
 	    suggestion.
 
+	    Invoke the DHCP script with action "tftp" when a TFTP file
+	    transfer completes. The size of the file, address to which
+	    it was sent and complete pathname are supplied. Note that
+	    version 2.60 introduced some script incompatibilties
+	    associated with DHCPv6, and this is a further change. To
+	    be safe, scripts should ignore unknown actions, and if
+	    not IPv6-aware, should exit if the environment
+	    variable DNSMASQ_IAID is set. The use-case for this is
+	    to track netboot/install.  Suggestion from Shantanu
+	    Gadgil.
+
+	    Update contrib/port-forward/dnsmasq-portforward to reflect
+	    the above.
+
+	    Set the environment variable DNSMASQ_LOG_DHCP when running
+	    the script id --log-dhcp is in effect, so that script can
+	    taylor their logging verbosity. Suggestion from Malte Forkel.
+
  
 version 2.60
             Fix compilation problem in Mac OS X Lion. Thanks to Olaf

contrib/port-forward/dnsmasq-portforward

@@ -34,11 +34,21 @@ if [ ${DNSMASQ_OLD_HOSTNAME} ] && [ ${action} = old ] ; then
     hostname=${DNSMASQ_OLD_HOSTNAME}
 fi
 
+# IPv6 leases are not our concern. no NAT there!
+if [ ${DNSMASQ_IAID} ] ; then
+   exit 0
+fi
+
 # action init is not relevant, and will only be seen when leasefile-ro is set.
 if [ ${action} = init ] ; then
     exit 0
 fi
 
+# action tftp is not relevant.
+if [ ${action} = tftp ] ; then
+    exit 0
+fi
+
 if [ ${hostname} ]; then
     ports=$(sed -n -e "/^${hostname}\ .*/ s/^.* //p" ${PORTSFILE})
 

man/dnsmasq.8

@@ -576,14 +576,14 @@ for details. Instead, the keyword
 .B ra-names
 may be used. This does the same at ra-only, but also enables a mode
 which gives DNS names to dual-stack hosts which do SLAAC for
-IPv6. Dnsmasq uses the hosts IPv4 lease to derive the name, network
+IPv6. Dnsmasq uses the host's IPv4 lease to derive the name, network
 segment and MAC address and assumes that the host will also have an
 IPv6 address calculated using the SLAAC alogrithm, on the same network
-segment. An AAAA record is added to the DNS for this IPv6
+segment. The address is pinged, and if a reply is received, an AAAA
+record is added to the DNS for this IPv6
 address. Note that this is only happens for directly-connected
-networks, (not one doing DHCP via a relay) and it will generate an
+networks, (not one doing DHCP via a relay) and it will not work 
-erroneous AAAA record if a host is using privacy extensions or does
+if a host is using privacy extensions. 
-not support IPv6. Use with care.
 
 The interface:<interface name> section is not normally used. See the
 NOTES section for details of this.
@@ -1069,7 +1069,8 @@ re-intialised. The enterprise-id is assigned by IANA, and the uid is a
 string of hex octets unique to a particular device.
 .TP
 .B \-6 --dhcp-script=<path>
-Whenever a new DHCP lease is created, or an old one destroyed, the
+Whenever a new DHCP lease is created, or an old one destroyed, or a
+TFTP file transfer completes, the
 executable specified by this option is run.  <path>
 must be an absolute pathname, no PATH search occurs. 
 The arguments to the process
@@ -1119,6 +1120,8 @@ is known.
 DNSMASQ_TAGS contains all the tags set during the
 DHCP transaction, separated by spaces.
 
+DNSMASQ_LOG_DHCP is set if --log-dhcp is in effect.
+
 For IPv4 only:
 
 DNSMASQ_CLIENT_ID if the host provided a client-id.
@@ -1145,6 +1148,8 @@ only  supplied for
 since these data are not held in dnsmasq's lease
 database.
 
+
+
 All file descriptors are
 closed except stdin, stdout and stderr which are open to /dev/null
 (except in debug mode).
@@ -1163,6 +1168,17 @@ all existing leases as they are read from the lease file. Expired
 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.
+
+
+There are two further actions which may appear as the first argument
+to the script, "init" and "tftp". More may be added in the future, so
+scripts should be written to ignore unknown actions. "init" is
+decsribed below in 
+.B --leasefile-ro
+The "tftp" action is invoked when a TFTP file transfer completes: the
+arguments are the file size in bytes, the address to which the file
+was sent, and the complete pathname of the file.
+ 
 .TP
 .B --dhcp-luascript=<path>
 Specify a script written in Lua, to be run when leases are created,
@@ -1176,11 +1192,13 @@ function, and may provide
 and
 .B shutdown
 functions, which are called, without arguments when dnsmasq starts up
-and terminates.
+and terminates. It may also provide a 
+.B tftp
+function.
 
 The 
 .B lease
-method receives the information detailed in 
+function 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
@@ -1198,6 +1216,15 @@ for IPv4, and
 and 
 .B hostname
 for IPv6.
+
+The  
+.B tftp
+function is called in the same way as the lease function, and the
+table holds the tags 
+.B destination_address,
+.B file_name
+and 
+.B file_size.
 .TP
 .B --dhcp-scriptuser
 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. 
@@ -1292,13 +1319,17 @@ only a subset of this is needed, and dnsmasq can handle it, using
 existing DHCP configuration to provide most data. When RA is enabled,
 dnsmasq will advertise a prefix for each dhcp-range, with default
 router and recursive DNS server as the relevant link-local address on 
-the machine running dnsmasq. The "managed address" bits are set,
+the machine running dnsmasq. The "managed address" bits are set, and
-except for a dhcp-range which is marked as "ra-only", in which case RA
+the "use SLAAC" bit is reset, except for a dhcp-range which is 
-is provided but no DHCPv6 service and the managed address bits are
+marked as "ra-only" or "ra-names", in which case RA is provided but no 
-cleared. 
+DHCPv6 service and the managed address bits are
+cleared and the "use SLAAC" bit set. If the same subnet appears in a
+normal dhcp-range and an "ra-only" dhcp-range, then the "managed
+address" bits and the "use SLAAC" bits are all set, allowing SLAAC and
+DHCP address to co-exist on the same subnet.  
 .B enable-ra
 enables router advertisement for prefixes where dnsmasq is doing
-DHCPv6. It is not needed to "ra-only" prefixes. Creating an "ra-only"
+DHCPv6. It is not needed for "ra-only" prefixes. Creating an "ra-only"
 prefix and not setting 
 .B enable-ra
 sends advertisements only to "ra-only" prefixes. 

src/dnsmasq.c

@@ -23,7 +23,6 @@ struct daemon *daemon;
 
 static volatile pid_t pid = 0;
 static volatile int pipewrite;
-static int alarm_queued = 0;
 
 static int set_dns_listeners(time_t now, fd_set *set, int *maxfdp);
 static void check_dns_listeners(fd_set *set, time_t now);
@@ -722,6 +721,10 @@ int main (int argc, char **argv)
 #  ifdef HAVE_SCRIPT
       while (helper_buf_empty() && do_script_run(now));
 
+#    ifdef HAVE_TFTP
+      while (helper_buf_empty() && do_tftp_script_run());
+#    endif
+
       if (!helper_buf_empty())
 	{
 	  FD_SET(daemon->helperfd, &wset);
@@ -730,6 +733,11 @@ int main (int argc, char **argv)
 #  else
       /* need this for other side-effects */
       while (do_script_run(now));
+
+#    ifdef HAVE_TFTP 
+      while (do_tftp_script_run());
+#    endif
+
 #  endif
 #endif
    
@@ -868,20 +876,14 @@ static void sig_handler(int sig)
 /* now == 0 -> queue immediate callback */
 void send_alarm(time_t event, time_t now)
 {
-  
+  if (now == 0 || event != 0)
-  if (now != 0 && event == 0)
+    {
-    return;
+      /* alarm(0) or alarm(-ve) doesn't do what we want.... */
-
       if ((now == 0 || difftime(event, now) <= 0.0))
-    {
-      if (!alarm_queued)
-	{
 	send_event(pipewrite, EVENT_ALARM, 0, NULL);
-	  alarm_queued = 1;
-	}
-    }
       else 
 	alarm((unsigned)difftime(event, now)); 
+    }
 }
 
 void send_event(int fd, int event, int data, char *msg)
@@ -995,7 +997,6 @@ static void async_event(int pipe, time_t now)
 	break;
 	
       case EVENT_ALARM:
-	alarm_queued = 0;
 #ifdef HAVE_DHCP
 	if (daemon->dhcp || daemon->dhcp6)
 	  {

src/dnsmasq.h

@@ -458,6 +458,7 @@ struct frec {
 #define ACTION_OLD_HOSTNAME  2
 #define ACTION_OLD           3
 #define ACTION_ADD           4
+#define ACTION_TFTP          5
 
 #define LEASE_NEW            1  /* newly created */
 #define LEASE_CHANGED        2  /* modified */
@@ -803,7 +804,7 @@ extern struct daemon {
 #endif
 
   /* TFTP stuff */
-  struct tftp_transfer *tftp_trans;
+  struct tftp_transfer *tftp_trans, *tftp_done_trans;
 
   /* utility string buffer, hold max sized IP address as string */
   char *addrbuff;
@@ -1035,11 +1036,14 @@ void emit_dbus_signal(int action, struct dhcp_lease *lease, char *hostname);
 #endif
 
 /* helper.c */
-#if defined(HAVE_DHCP) && !defined(NO_FORK)
+#if defined(HAVE_SCRIPT)
 int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd);
 void helper_write(void);
 void queue_script(int action, struct dhcp_lease *lease, 
 		  char *hostname, time_t now);
+#ifdef HAVE_TFTP
+void queue_tftp(off_t file_len, char *filename, union mysockaddr *peer);
+#endif
 int helper_buf_empty(void);
 #endif
 
@@ -1047,6 +1051,7 @@ int helper_buf_empty(void);
 #ifdef HAVE_TFTP
 void tftp_request(struct listener *listen, time_t now);
 void check_tftp_listeners(fd_set *rset, time_t now);
+int do_tftp_script_run(void);
 #endif
 
 /* conntrack.c */

src/helper.c

@@ -193,16 +193,22 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	  _exit(0);
 	}
  
+      is6 = !!(data.flags & (LEASE_TA | LEASE_NA));
+      
       if (data.action == ACTION_DEL)
 	action_str = "del";
       else if (data.action == ACTION_ADD)
 	action_str = "add";
       else if (data.action == ACTION_OLD || data.action == ACTION_OLD_HOSTNAME)
 	action_str = "old";
+      else if (data.action == ACTION_TFTP)
+	{
+	  action_str = "tftp";
+	  is6 = (data.flags != AF_INET);
+	}
       else
 	continue;
 
-      is6 = !!(data.flags & (LEASE_TA | LEASE_NA));
       	
       if (!is6)
 	{
@@ -271,6 +277,8 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	  char *dot;
 	  hostname = (char *)buf;
 	  hostname[data.hostname_len - 1] = 0;
+	  if (data.action != ACTION_TFTP)
+	    {
 	      if (!legal_hostname(hostname))
 		hostname = NULL;
 	      else if ((dot = strchr(hostname, '.')))
@@ -279,6 +287,7 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 		  *dot = 0;
 		} 
 	    }
+	}
     
       extradata = buf + data.hostname_len;
     
@@ -289,8 +298,32 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	inet_ntop(AF_INET6, &data.hwaddr, daemon->addrbuff, ADDRSTRLEN);
 #endif
 
+      /* file length */
+      if (data.action == ACTION_TFTP)
+	sprintf(daemon->dhcp_buff, "%u", data.hwaddr_len);
+      
 #ifdef HAVE_LUASCRIPT
       if (daemon->luascript)
+	{
+	  if (data.action == ACTION_TFTP)
+	    {
+	      lua_getglobal(lua, "tftp"); 
+	      if (lua_type(lua, -1) != LUA_TFUNCTION)
+		lua_pop(lua, 1); /* tftp function optional */
+	      else
+		{
+		  lua_pushstring(lua, action_str); /* arg1 - action */
+		  lua_newtable(lua);               /* arg2 - data table */
+		  lua_pushstring(lua, daemon->addrbuff);
+		  lua_setfield(lua, -2, "destination_address");
+		  lua_pushstring(lua, hostname);
+		  lua_setfield(lua, -2, "file_name"); 
+		  lua_pushstring(lua, daemon->dhcp_buff);
+		  lua_setfield(lua, -2, "file_size");
+		  lua_call(lua, 2, 0);	/* pass 2 values, expect 0 */
+		}
+	    }
+	  else
 	    {
 	      lua_getglobal(lua, "lease");     /* function to call */
 	      lua_pushstring(lua, action_str); /* arg1 - action */
@@ -400,6 +433,7 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	    
 	      lua_call(lua, 2, 0);	/* pass 2 values, expect 0 */
 	    }
+	}
 #endif
 
       /* no script, just lua */
@@ -439,6 +473,8 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	  continue;
 	}
       
+      if (data.action != ACTION_TFTP)
+	{
 	  if (is6)
 	    {
 	      my_setenv("DNSMASQ_IAID", daemon->dhcp_buff3, &err);
@@ -513,6 +549,10 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	      my_setenv("DNSMASQ_OLD_HOSTNAME", hostname, &err);
 	      hostname = NULL;
 	    }
+	}
+
+      if (option_bool(OPT_LOG_OPTS))
+	my_setenv("DNSMASQ_LOG_DHCP", "1", &err);
 	 
       /* we need to have the event_fd around if exec fails */
       if ((i = fcntl(event_fd, F_GETFD)) != -1)
@@ -584,11 +624,29 @@ static unsigned char *grab_extradata_lua(unsigned char *buf, unsigned char *end,
 }
 #endif
 
+static void buff_alloc(size_t size)
+{
+  if (size > buf_size)
+    {
+      struct script_data *new;
+      
+      /* start with reasonable size, will almost never need extending. */
+      if (size < sizeof(struct script_data) + 200)
+	size = sizeof(struct script_data) + 200;
+
+      if (!(new = whine_malloc(size)))
+	return;
+      if (buf)
+	free(buf);
+      buf = new;
+      buf_size = size;
+    }
+}
+
 /* pack up lease data into a buffer */    
 void queue_script(int action, struct dhcp_lease *lease, char *hostname, time_t now)
 {
   unsigned char *p;
-  size_t size;
   unsigned int hostname_len = 0, clid_len = 0, ed_len = 0;
   int fd = daemon->dhcpfd;
 
@@ -608,23 +666,7 @@ void queue_script(int action, struct dhcp_lease *lease, char *hostname, time_t n
   if (hostname)
     hostname_len = strlen(hostname) + 1;
 
-  size = sizeof(struct script_data) +  clid_len + ed_len + hostname_len;
+  buff_alloc(sizeof(struct script_data) +  clid_len + ed_len + hostname_len);
-
-  if (size > buf_size)
-    {
-      struct script_data *new;
-      
-      /* start with reasonable size, will almost never need extending. */
-      if (size < sizeof(struct script_data) + 200)
-	size = sizeof(struct script_data) + 200;
-
-      if (!(new = whine_malloc(size)))
-	return;
-      if (buf)
-	free(buf);
-      buf = new;
-      buf_size = size;
-    }
 
   buf->action = action;
   buf->flags = lease->flags;
@@ -669,6 +711,37 @@ void queue_script(int action, struct dhcp_lease *lease, char *hostname, time_t n
   bytes_in_buf = p - (unsigned char *)buf;
 }
 
+#ifdef HAVE_TFTP
+/* This nastily re-uses DHCP-fields for TFTP stuff */
+void queue_tftp(off_t file_len, char *filename, union mysockaddr *peer)
+{
+  unsigned int filename_len;
+
+  /* no script */
+  if (daemon->helperfd == -1)
+    return;
+  
+  filename_len = strlen(filename) + 1;
+  buff_alloc(sizeof(struct script_data) +  filename_len);
+  memset(buf, 0, sizeof(struct script_data));
+
+  buf->action = ACTION_TFTP;
+  buf->hostname_len = filename_len;
+  buf->hwaddr_len = file_len;
+
+  if ((buf->flags = peer->sa.sa_family) == AF_INET)
+    buf->addr = peer->in.sin_addr;
+#ifdef HAVE_IPV6
+  else
+    memcpy(buf->hwaddr, &peer->in6.sin6_addr, IN6ADDRSZ);
+#endif
+
+  memcpy((unsigned char *)(buf+1), filename, filename_len);
+  
+  bytes_in_buf = sizeof(struct script_data) +  filename_len;
+}
+#endif
+
 int helper_buf_empty(void)
 {
   return bytes_in_buf == 0;

src/radv.c

@@ -206,7 +206,7 @@ static void send_ra(int iface, char *iface_name, struct in6_addr *dest)
   ra->type = ND_ROUTER_ADVERT;
   ra->code = 0;
   ra->hop_limit = hop_limit;
-  ra->flags = 0;
+  ra->flags = 0x00;
   ra->lifetime = htons(1800); /* AdvDefaultLifetime*/
   ra->reachable_time = 0;
   ra->retrans_time = 0;
@@ -246,7 +246,7 @@ static void send_ra(int iface, char *iface_name, struct in6_addr *dest)
 
   /* set managed bits unless we're providing only RA on this link */
   if (parm.managed)
-    ra->flags = 0xc0; 
+    ra->flags = 0xc0; /* M flag, managed, O flag, other */ 
 
   /* decide where we're sending */
   memset(&addr, 0, sizeof(addr));
@@ -293,7 +293,11 @@ static int add_prefixes(struct in6_addr *local,  int prefix,
 		is_same_net6(local, &context->start6, prefix) &&
 		is_same_net6(local, &context->end6, prefix))
 	      {
-		if (!(context->flags & CONTEXT_RA_ONLY))
+		int do_slaac = 0;
+
+		if (context->flags & CONTEXT_RA_ONLY)
+		  do_slaac = 1;
+		else
 		  {
 		    /* don't do RA for non-ra-only unless --enable-ra is set */
 		    if (!option_bool(OPT_RA))
@@ -317,6 +321,10 @@ static int add_prefixes(struct in6_addr *local,  int prefix,
 		      is_same_net6(local, &tmp->start6, prefix) &&
 		      is_same_net6(local, &tmp->end6, prefix))
 		    {
+		      /* if any dhcp-range with ra-only on this subnet
+			 set the "do_slaac" bit */
+		      if (tmp->flags & CONTEXT_RA_ONLY)
+			do_slaac = 1;
 		      tmp->flags |= CONTEXT_RA_DONE;
 		      context->ra_time = 0;
 		    }
@@ -335,7 +343,7 @@ static int add_prefixes(struct in6_addr *local,  int prefix,
 		    opt->len = 4;
 		    opt->prefix_len = prefix;
 		    /* autonomous only is we're not doing dhcp */
-		    opt->flags = (context->flags & CONTEXT_RA_ONLY) ? 0xc0 : 0x00;
+		    opt->flags = do_slaac ? 0x40 : 0x00;
 		    opt->valid_lifetime = opt->preferred_lifetime = htonl(time);
 		    opt->reserved = 0;
 		    

src/tftp.c

@@ -571,7 +571,9 @@ void check_tftp_listeners(fd_set *rset, time_t now)
 		my_syslog(MS_TFTP | LOG_INFO, _("sent %s to %s"), transfer->file->filename, daemon->addrbuff);
 	      /* unlink */
 	      *up = tmp;
-	      free_transfer(transfer);
+	      /* put on queue to be sent to script and deleted */
+	      transfer->next = daemon->tftp_done_trans;
+	      daemon->tftp_done_trans = transfer;
 	      continue;
 	    }
 	}
@@ -709,4 +711,21 @@ static ssize_t get_block(char *packet, struct tftp_transfer *transfer)
     }
 }
 
+
+int do_tftp_script_run(void)
+{
+  struct tftp_transfer *transfer;
+
+  if ((transfer = daemon->tftp_done_trans))
+    {
+      daemon->tftp_done_trans = transfer->next;
+#ifdef HAVE_SCRIPT
+      queue_tftp(transfer->file->size, transfer->file->filename, &transfer->peer);
+#endif
+      free_transfer(transfer);
+      return 1;
+    }
+
+  return 0;
+}
 #endif