ntp: use separate client sockets

Use separate sockets for NTP server or peer and client packets. The port
number is configured by the acquisitionport directive. With the default
value of 0 the port is assigned randomly by the kernel. It can be equal
to the value configured by the port directive to use the server sockets
for all packets as before.

diff --git a/ntp_io.c b/ntp_io.c
index 359f76a9eca6c254863c0f02c85daa20e988c6a0..81acfd4c74587106d885b3e350a2ed5c30dbbe98 100644 (file)
--- a/ntp_io.c
+++ b/ntp_io.c
@@ -49,10 +49,12 @@ union sockaddr_in46 {
   struct sockaddr u;
 };
 
-/* The file descriptors for the IPv4 and IPv6 sockets */
-static int sock_fd4;
+/* The server/peer and client sockets for IPv4 and IPv6 */
+static int server_sock_fd4;
+static int client_sock_fd4;
 #ifdef HAVE_IPV6
-static int sock_fd6;
+static int server_sock_fd6;
+static int client_sock_fd6;
 #endif
 
 /* Flag indicating that we have been initialised */
@@ -61,7 +63,6 @@ static int initialised=0;
 /* ================================================== */
 
 /* Forward prototypes */
-static int prepare_socket(int family);
 static void read_from_socket(void *anything);
 
 /* ================================================== */
@@ -94,17 +95,14 @@ do_size_checks(void)
 /* ================================================== */
 
 static int
-prepare_socket(int family)
+prepare_socket(int family, int port_number)
 {
   union sockaddr_in46 my_addr;
   socklen_t my_addr_len;
   int sock_fd;
-  unsigned short port_number;
   IPAddr bind_address;
   int on_off = 1;
   
-  port_number = CNF_GetNTPPort();
-
   /* Open Internet domain UDP socket for NTP message transmissions */
 
 #if 0
@@ -235,31 +233,65 @@ prepare_socket(int family)
 
 /* ================================================== */
 
+static void
+close_socket(int sock_fd)
+{
+  if (sock_fd == INVALID_SOCK_FD)
+    return;
+
+  SCH_RemoveInputFileHandler(sock_fd);
+  close(sock_fd);
+}
+
+/* ================================================== */
+
 void
 NIO_Initialise(int family)
 {
+  int server_port, client_port;
+
   assert(!initialised);
   initialised = 1;
 
   do_size_checks();
 
-  if (family == IPADDR_UNSPEC || family == IPADDR_INET4)
-    sock_fd4 = prepare_socket(AF_INET);
-  else
-    sock_fd4 = INVALID_SOCK_FD;
+  server_port = CNF_GetNTPPort();
+  client_port = CNF_GetAcquisitionPort();
+
+  server_sock_fd4 = INVALID_SOCK_FD;
+  client_sock_fd4 = INVALID_SOCK_FD;
+#ifdef HAVE_IPV6
+  server_sock_fd6 = INVALID_SOCK_FD;
+  client_sock_fd6 = INVALID_SOCK_FD;
+#endif
+
+  if (family == IPADDR_UNSPEC || family == IPADDR_INET4) {
+    server_sock_fd4 = prepare_socket(AF_INET, server_port);
+    if (client_port != server_port || !server_port)
+      client_sock_fd4 = prepare_socket(AF_INET, client_port);
+    else
+      client_sock_fd4 = server_sock_fd4;
+  }
 #ifdef HAVE_IPV6
-  if (family == IPADDR_UNSPEC || family == IPADDR_INET6)
-    sock_fd6 = prepare_socket(AF_INET6);
-  else
-    sock_fd6 = INVALID_SOCK_FD;
+  if (family == IPADDR_UNSPEC || family == IPADDR_INET6) {
+    server_sock_fd6 = prepare_socket(AF_INET6, server_port);
+    if (client_port != server_port || !server_port)
+      client_sock_fd6 = prepare_socket(AF_INET6, client_port);
+    else
+      client_sock_fd6 = server_sock_fd6;
+  }
 #endif
 
-  if (sock_fd4 == INVALID_SOCK_FD
+  if ((server_sock_fd4 == INVALID_SOCK_FD
+#ifdef HAVE_IPV6
+       && server_sock_fd6 == INVALID_SOCK_FD
+#endif
+      ) || (client_sock_fd4 == INVALID_SOCK_FD
 #ifdef HAVE_IPV6
-      && sock_fd6 == INVALID_SOCK_FD
+       && client_sock_fd6 == INVALID_SOCK_FD
 #endif
-      ) {
-    LOG_FATAL(LOGF_NtpIO, "Could not open any NTP socket");
+      )) {
+    LOG_FATAL(LOGF_NtpIO, "Could not open NTP sockets");
   }
 }
 
@@ -268,17 +300,15 @@ NIO_Initialise(int family)
 void
 NIO_Finalise(void)
 {
-  if (sock_fd4 != INVALID_SOCK_FD) {
-    SCH_RemoveInputFileHandler(sock_fd4);
-    close(sock_fd4);
-  }
-  sock_fd4 = INVALID_SOCK_FD;
+  if (server_sock_fd4 != client_sock_fd4)
+    close_socket(client_sock_fd4);
+  close_socket(server_sock_fd4);
+  server_sock_fd4 = client_sock_fd4 = INVALID_SOCK_FD;
 #ifdef HAVE_IPV6
-  if (sock_fd6 != INVALID_SOCK_FD) {
-    SCH_RemoveInputFileHandler(sock_fd6);
-    close(sock_fd6);
-  }
-  sock_fd6 = INVALID_SOCK_FD;
+  if (server_sock_fd6 != client_sock_fd6)
+    close_socket(client_sock_fd6);
+  close_socket(server_sock_fd6);
+  server_sock_fd6 = client_sock_fd6 = INVALID_SOCK_FD;
 #endif
   initialised = 0;
 }
@@ -288,7 +318,16 @@ NIO_Finalise(void)
 int
 NIO_GetClientSocket(NTP_Remote_Address *remote_addr)
 {
-  return NIO_GetServerSocket(remote_addr);
+  switch (remote_addr->ip_addr.family) {
+    case IPADDR_INET4:
+      return client_sock_fd4;
+#ifdef HAVE_IPV6
+    case IPADDR_INET6:
+      return client_sock_fd6;
+#endif
+    default:
+      return INVALID_SOCK_FD;
+  }
 }
 
 /* ================================================== */
@@ -298,10 +337,10 @@ NIO_GetServerSocket(NTP_Remote_Address *remote_addr)
 {
   switch (remote_addr->ip_addr.family) {
     case IPADDR_INET4:
-      return sock_fd4;
+      return server_sock_fd4;
 #ifdef HAVE_IPV6
     case IPADDR_INET6:
-      return sock_fd6;
+      return server_sock_fd6;
 #endif
     default:
       return INVALID_SOCK_FD;