ntpd.h, ntpd.c, ntp_timer.c, ntp_io.c, cmd_args.c:

  disable dynamic update when giving up the root privilege

bk: 45156d98_LKtm_adWalp1HX2GnFPOA

diff --git a/include/ntpd.h b/include/ntpd.h
index d51ddf74f1625ff14c8b744c7861df465fa3d4fe..3495cc85d4d83455ce051a7272151d3462e57380 100644 (file)
--- a/include/ntpd.h
+++ b/include/ntpd.h
@@ -70,6 +70,8 @@ typedef struct interface_info {
 
 typedef void (*interface_receiver_t)(void *, interface_info_t *);
 
+extern  volatile int disable_dynamic_updates;
+
 extern  void    interface_enumerate P((interface_receiver_t, void *));
 extern struct interface *findinterface P((struct sockaddr_storage *));
 extern  struct interface *findbcastinter P((struct sockaddr_storage *));
@@ -220,6 +222,7 @@ extern      void    reinit_timer    P((void));
 extern void    timer           P((void));
 extern void    timer_clr_stats P((void));
 extern  void    timer_interfacetimeout P((u_long));
+extern  volatile int interface_interval;
 
 #ifdef OPENSSL
 extern char    *sys_hostname;

diff --git a/ntpd/cmd_args.c b/ntpd/cmd_args.c
index f89e37be031742da8ddb597380e75af89ccae231..c71167ec1bb6a69b34b03897b8dabf89d60fcab6 100644 (file)
--- a/ntpd/cmd_args.c
+++ b/ntpd/cmd_args.c
@@ -184,7 +184,6 @@ getCmdOpts(
 
        if (HAVE_OPT( UPDATEINTERVAL )) {
                long val = OPT_VALUE_UPDATEINTERVAL;
-               extern int interface_interval;
                          
                if ((val >= 60) || (val == 0))
                        interface_interval = val;

diff --git a/ntpd/ntp_io.c b/ntpd/ntp_io.c
index 8027dd9b950f9a4a9693e8c86b828d4dff5a0958..b3b70ae3fde5434c327fd2a78524a3e5aa7b9582 100644 (file)
--- a/ntpd/ntp_io.c
+++ b/ntpd/ntp_io.c
@@ -132,6 +132,8 @@ struct interface *loopback_interface;       /* loopback ipv4 interface */
 
 int ninterfaces;                       /* Total number of interfaces */
 
+volatile int disable_dynamic_updates;   /* when set to != 0 dynamic updates won't happen */
+
 #ifdef REFCLOCK
 /*
  * Refclock stuff.     We keep a chain of structures with data concerning
@@ -1034,9 +1036,11 @@ refresh_interface(struct interface * interface)
 void
 interface_update(interface_receiver_t receiver, void *data)
 {
-       BLOCKIO();
-       update_interfaces(htons(NTP_PORT), receiver, data);
-       UNBLOCKIO();
+       if (!disable_dynamic_updates) {
+               BLOCKIO();
+               update_interfaces(htons(NTP_PORT), receiver, data);
+               UNBLOCKIO();
+       }
 }
 
 /*
@@ -1060,6 +1064,7 @@ is_wildcard_addr(struct sockaddr_storage *sas)
        return 0;
 }
 
+#ifdef OS_NEEDS_REUSEADDR_FOR_IFADDRBIND
 /*
  * enable/disable re-use of wildcard address socket
  */
@@ -1100,6 +1105,7 @@ set_wildcard_reuse(int family, int on)
                                  &any_interface->sin : &any6_interface->sin)));
        }
 }
+#endif /* OS_NEEDS_REUSEADDR_FOR_IFADDRBIND */
 
 /*
  * update_interface strategy
@@ -1115,7 +1121,7 @@ set_wildcard_reuse(int family, int on)
  *     attempt to create a new interface entry
  *
  * Phase 2:
- * forall currently known interfaces
+ * forall currently known non MCAST and WILDCARD interfaces
  *   if interface does not match configuration phase (not seen in phase 1):
  *     remove interface from known interface list
  *     forall peers associated with this interface
@@ -1996,6 +2002,7 @@ io_multicast_add(
                                                htonl(~(u_int32)0);
                DPRINT_INTERFACE(2, (interface, "multicast add ", "\n"));
                add_interface(interface);
+               list_if_listening(interface, NTP_PORT);
        }
        else
        {
@@ -3686,6 +3693,16 @@ process_routing_msgs(struct asyncio_reader *reader)
 
        int cnt;
        
+       if (disable_dynamic_updates) {
+               /*
+                * discard ourselves if we are not need any more
+                * usually happens when running unprivileged
+                */
+               remove_asyncio_reader(reader);
+               delete_asyncio_reader(reader);
+               return;
+       }
+
        cnt = read(reader->fd, buffer, sizeof(buffer));
        
        if (cnt < 0) {
@@ -3776,7 +3793,7 @@ init_async_notifications()
                reader->fd = fd;
                reader->receiver = process_routing_msgs;
                
-               add_asyncio_reader(reader, FD_TYPE_FILE);
+               add_asyncio_reader(reader, FD_TYPE_SOCKET);
                msyslog(LOG_INFO, "Listening on routing socket on fd #%d for interface updates", fd);
        } else {
                msyslog(LOG_ERR, "unable to open routing socket (%m) - using polled interface update");

diff --git a/ntpd/ntp_timer.c b/ntpd/ntp_timer.c
index bd01745b07694074f0ff04cf67af427afa7db688..fb6de702ac89f77d288d8bcb40b79178ffae2c65 100644 (file)
--- a/ntpd/ntp_timer.c
+++ b/ntpd/ntp_timer.c
@@ -34,7 +34,7 @@
  * procedure to do cleanup and print a message.
  */
 
-volatile u_long interface_interval = 300;     /* update interface every 5 minutes as default */
+volatile int interface_interval = 300;     /* update interface every 5 minutes as default */
          
 /*
  * Alarm flag. The mainline code imports this.

diff --git a/ntpd/ntpd.c b/ntpd/ntpd.c
index 29feb2f432cae9136d66beab8b59738db17a0bd2..6b01881c0637465f21349a1a605ec2d80b8f0dde 100644 (file)
--- a/ntpd/ntpd.c
+++ b/ntpd/ntpd.c
@@ -930,6 +930,18 @@ getgroup:
                        exit (-1);
                }
        
+               /*
+                * for now assume that the privilege to bind to privileged ports
+                * is associated with running with uid 0 - should be refined on
+                * ports that allow binding to NTP_PORT with uid != 0
+                */
+               disable_dynamic_updates |= (sw_uid != 0);  /* also notifies routing message listener */
+
+               if (disable_dynamic_updates && interface_interval) {
+                       interface_interval = 0;
+                       msyslog(LOG_INFO, "running in unprivileged mode disables dynamic interface tracking");
+               }
+
 #ifdef HAVE_LINUX_CAPABILITIES
                do {
                        /*  We may be running under non-root uid now, but we still hold full root privileges!