Rewrite socket code to support new network abstraction

2 files changed, 106 insertions, 26 deletions

diff --git a/common/socket.c b/common/socket.c
index 90335ebe..2218dd4b 100644
--- a/common/socket.c
+++ b/common/socket.c
@@ -47,7 +47,9 @@ static char copyright[] =
 
 #include "dhcpd.h"
 
-void if_register_socket (info, interface)
+#if defined (USE_SOCKET_SEND) || defined (USE_SOCKET_RECEIVE)
+/* Generic interface registration routine... */
+int if_register_socket (info, interface)
 	struct interface_info *info;
 	struct ifreq *interface;
 {
@@ -55,10 +57,22 @@ void if_register_socket (info, interface)
 	int sock;
 	struct socklist *tmp;
 	int flag;
+	static int once = 0;
 
+	/* Make sure only one interface is registered. */
+	if (once)
+		error ("The standard socket API can only support hosts "
+		       "with a single network interface.   If you must "
+		       "run dhcpd on a host with multiple interfaces, "
+		       "you must compile in BPF or NIT support.   If neither "
+		       "option is supported on your system, please let us "
+		       "know.");
+	once = 1;
+
+	/* Set up the address we're going to bind to. */
 	name.sin_family = AF_INET;
 	name.sin_port = server_port;
-	memcpy (&name.sin_addr.s_addr, info -> address.iabuf, 4);
+	name.sin_addr.s_addr = INADDR_ANY;
 	memset (name.sin_zero, 0, sizeof (name.sin_zero));
 
 	/* List addresses on which we're listening. */
@@ -67,35 +81,58 @@ void if_register_socket (info, interface)
 	if ((sock = socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
 		error ("Can't create dhcp socket: %m");
 
+	/* Set the REUSEADDR option so that we don't fail to start if
+	   we're being restarted. */
 	flag = 1;
 	if (setsockopt (sock, SOL_SOCKET, SO_REUSEADDR,
 			&flag, sizeof flag) < 0)
 		error ("Can't set SO_REUSEADDR option on dhcp socket: %m");
 
+	/* Set the BROADCAST option so that we can broadcast DHCP responses. */
 	if (setsockopt (sock, SOL_SOCKET, SO_BROADCAST,
 			&flag, sizeof flag) < 0)
 		error ("Can't set SO_BROADCAST option on dhcp socket: %m");
 
+	/* Bind the socket to this interface's IP address. */
 	if (bind (sock, (struct sockaddr *)&name, sizeof name) < 0)
 		error ("Can't bind to dhcp address: %m");
 
-	info -> rfdesc = sock;
+	return sock;
 }
+#endif /* USE_SOCKET_SEND || USE_SOCKET_RECEIVE */
 
 #ifdef USE_SOCKET_SEND
 void if_register_send (info, interface)
 	struct interface_info *info;
 	struct ifreq *interface;
 {
-	if_register_socket (info, interface);
+#ifndef USE_SOCKET_RECEIVE
+	info -> wfdesc = if_register_socket (info, interface);
+#else
+	info -> wfdesc = info -> rfdesc;
+#endif
 }
+#endif /* USE_SOCKET_SEND */
 
-int send_packet (interface, packet, raw, len, to, hto)
+#ifdef USE_SOCKET_RECEIVE
+void if_register_receive (info, interface)
+	struct interface_info *info;
+	struct ifreq *interface;
+{
+	/* If we're using the socket API for sending and receiving,
+	   we don't need to register this interface twice. */
+	info -> rfdesc = if_register_socket (info, interface);
+}
+#endif /* USE_SOCKET_RECEIVE */
+
+#ifdef USE_SOCKET_SEND
+size_t send_packet (interface, packet, raw, len, to, hto)
+	struct interface_info *interface;
 	struct packet *packet;
 	struct dhcp_packet *raw;
 	size_t len;
 	struct sockaddr_in *to;
-	struct hardware_addr *hto;
+	struct hardware *hto;
 {
 	return sendto (interface -> wfdesc, raw, len, 0,
 		       (struct sockaddr *)to, sizeof *to);
@@ -103,13 +140,16 @@ int send_packet (interface, packet, raw, len, to, hto)
 #endif /* USE_SOCKET_SEND */
 
 #ifdef USE_SOCKET_RECEIVE
-void if_register_send (info, interface)
-	struct interface_info *info;
-	struct ifreq *interface;
+size_t receive_packet (interface, buf, len, from, hfrom)
+	struct interface_info *interface;
+	unsigned char *buf;
+	size_t len;
+	struct sockaddr_in *from;
+	struct hardware *hfrom;
 {
-/* Do nothing unless we're using a different API for sending packets... */
-#ifndef USE_SOCKET_SEND
-	if_register_socket (info, interface);
-#endif
+	int flen = sizeof *from;
+
+	return recvfrom (interface -> rfdesc, buf, len, 0,
+			 (struct sockaddr *)from, &flen);
 }
 #endif /* USE_SOCKET_RECEIVE */
diff --git a/socket.c b/socket.c
index 90335ebe..2218dd4b 100644
--- a/socket.c
+++ b/socket.c
@@ -47,7 +47,9 @@ static char copyright[] =
 
 #include "dhcpd.h"
 
-void if_register_socket (info, interface)
+#if defined (USE_SOCKET_SEND) || defined (USE_SOCKET_RECEIVE)
+/* Generic interface registration routine... */
+int if_register_socket (info, interface)
 	struct interface_info *info;
 	struct ifreq *interface;
 {
@@ -55,10 +57,22 @@ void if_register_socket (info, interface)
 	int sock;
 	struct socklist *tmp;
 	int flag;
+	static int once = 0;
 
+	/* Make sure only one interface is registered. */
+	if (once)
+		error ("The standard socket API can only support hosts "
+		       "with a single network interface.   If you must "
+		       "run dhcpd on a host with multiple interfaces, "
+		       "you must compile in BPF or NIT support.   If neither "
+		       "option is supported on your system, please let us "
+		       "know.");
+	once = 1;
+
+	/* Set up the address we're going to bind to. */
 	name.sin_family = AF_INET;
 	name.sin_port = server_port;
-	memcpy (&name.sin_addr.s_addr, info -> address.iabuf, 4);
+	name.sin_addr.s_addr = INADDR_ANY;
 	memset (name.sin_zero, 0, sizeof (name.sin_zero));
 
 	/* List addresses on which we're listening. */
@@ -67,35 +81,58 @@ void if_register_socket (info, interface)
 	if ((sock = socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
 		error ("Can't create dhcp socket: %m");
 
+	/* Set the REUSEADDR option so that we don't fail to start if
+	   we're being restarted. */
 	flag = 1;
 	if (setsockopt (sock, SOL_SOCKET, SO_REUSEADDR,
 			&flag, sizeof flag) < 0)
 		error ("Can't set SO_REUSEADDR option on dhcp socket: %m");
 
+	/* Set the BROADCAST option so that we can broadcast DHCP responses. */
 	if (setsockopt (sock, SOL_SOCKET, SO_BROADCAST,
 			&flag, sizeof flag) < 0)
 		error ("Can't set SO_BROADCAST option on dhcp socket: %m");
 
+	/* Bind the socket to this interface's IP address. */
 	if (bind (sock, (struct sockaddr *)&name, sizeof name) < 0)
 		error ("Can't bind to dhcp address: %m");
 
-	info -> rfdesc = sock;
+	return sock;
 }
+#endif /* USE_SOCKET_SEND || USE_SOCKET_RECEIVE */
 
 #ifdef USE_SOCKET_SEND
 void if_register_send (info, interface)
 	struct interface_info *info;
 	struct ifreq *interface;
 {
-	if_register_socket (info, interface);
+#ifndef USE_SOCKET_RECEIVE
+	info -> wfdesc = if_register_socket (info, interface);
+#else
+	info -> wfdesc = info -> rfdesc;
+#endif
 }
+#endif /* USE_SOCKET_SEND */
 
-int send_packet (interface, packet, raw, len, to, hto)
+#ifdef USE_SOCKET_RECEIVE
+void if_register_receive (info, interface)
+	struct interface_info *info;
+	struct ifreq *interface;
+{
+	/* If we're using the socket API for sending and receiving,
+	   we don't need to register this interface twice. */
+	info -> rfdesc = if_register_socket (info, interface);
+}
+#endif /* USE_SOCKET_RECEIVE */
+
+#ifdef USE_SOCKET_SEND
+size_t send_packet (interface, packet, raw, len, to, hto)
+	struct interface_info *interface;
 	struct packet *packet;
 	struct dhcp_packet *raw;
 	size_t len;
 	struct sockaddr_in *to;
-	struct hardware_addr *hto;
+	struct hardware *hto;
 {
 	return sendto (interface -> wfdesc, raw, len, 0,
 		       (struct sockaddr *)to, sizeof *to);
@@ -103,13 +140,16 @@ int send_packet (interface, packet, raw, len, to, hto)
 #endif /* USE_SOCKET_SEND */
 
 #ifdef USE_SOCKET_RECEIVE
-void if_register_send (info, interface)
-	struct interface_info *info;
-	struct ifreq *interface;
+size_t receive_packet (interface, buf, len, from, hfrom)
+	struct interface_info *interface;
+	unsigned char *buf;
+	size_t len;
+	struct sockaddr_in *from;
+	struct hardware *hfrom;
 {
-/* Do nothing unless we're using a different API for sending packets... */
-#ifndef USE_SOCKET_SEND
-	if_register_socket (info, interface);
-#endif
+	int flen = sizeof *from;
+
+	return recvfrom (interface -> rfdesc, buf, len, 0,
+			 (struct sockaddr *)from, &flen);
 }
 #endif /* USE_SOCKET_RECEIVE */