nic_router: verbose_packet_drop attribute

The log messages covered by verbose_packet_drop were previously
configured by the verbose attribute. This isn't the case anymore. Now,
you can configure them as follows:

! <config verbose_packet_drop="no" ... >
!     <domain verbose_packet_drop="no" ... />
! <config/>

The new attribute determines whether to log each packet drop and the
rational behind it. The <config> value affects all domains without a
<domain> local value.

Issue #2857

repos/os/src/server/nic_router/README

@@ -481,6 +481,13 @@ Whether to log most important protocol header fields of each packet that is
 received or sent (ETH, IPv4, ARP, UDP, TCP, DHCP, ICMP). The <config> value
 affects all domains without a <domain> local value.
 
+! <config verbose_packet_drop="no" ... >
+!     <domain verbose_packet_drop="no" ... />
+! <config/>
+
+Whether to log each packet drop and the rational behind it. The <config> value
+affects all domains without a <domain> local value.
+
 ! <config verbose_domain_state="no">
 
 Whether to log most important changes in the state of a domain (number of NIC

repos/os/src/server/nic_router/config.xsd

@@ -155,6 +155,7 @@
 						<xs:attribute name="interface"           type="Ipv4_address_prefix" />
 						<xs:attribute name="gateway"             type="Ipv4_address" />
 						<xs:attribute name="verbose_packets"     type="Boolean" />
+						<xs:attribute name="verbose_packet_drop" type="Boolean" />
 						<xs:attribute name="label"               type="Session_label" />
 						<xs:attribute name="icmp_echo_server"    type="Boolean" />
 					</xs:complexType>
@@ -163,6 +164,7 @@
 			</xs:choice>
 			<xs:attribute name="verbose"                   type="Boolean" />
 			<xs:attribute name="verbose_packets"           type="Boolean" />
+			<xs:attribute name="verbose_packet_drop"       type="Boolean" />
 			<xs:attribute name="verbose_domain_state"      type="Boolean" />
 			<xs:attribute name="dhcp_discover_timeout_sec" type="Seconds" />
 			<xs:attribute name="dhcp_request_timeout_sec"  type="Seconds" />

repos/os/src/server/nic_router/configuration.cc

@@ -67,6 +67,7 @@ Configuration::Configuration(Env               &env,
 	_alloc(alloc),
 	_verbose              (node.attribute_value("verbose",              false)),
 	_verbose_packets      (node.attribute_value("verbose_packets",      false)),
+	_verbose_packet_drop  (node.attribute_value("verbose_packet_drop",  false)),
 	_verbose_domain_state (node.attribute_value("verbose_domain_state", false)),
 	_icmp_echo_server     (node.attribute_value("icmp_echo_server",     true)),
 	_dhcp_discover_timeout(read_sec_attr(node, "dhcp_discover_timeout_sec", DEFAULT_DHCP_DISCOVER_TIMEOUT_SEC)),

repos/os/src/server/nic_router/configuration.h

@@ -36,6 +36,7 @@ class Net::Configuration
 		Genode::Allocator          &_alloc;
 		bool                 const  _verbose                 { false };
 		bool                 const  _verbose_packets         { false };
+		bool                 const  _verbose_packet_drop     { false };
 		bool                 const  _verbose_domain_state    { false };
 		bool                 const  _icmp_echo_server        { true };
 		Genode::Microseconds const  _dhcp_discover_timeout   { DEFAULT_DHCP_DISCOVER_TIMEOUT_SEC };
@@ -87,6 +88,7 @@ class Net::Configuration
 
 		bool                  verbose()               const { return _verbose; }
 		bool                  verbose_packets()       const { return _verbose_packets; }
+		bool                  verbose_packet_drop()   const { return _verbose_packet_drop; }
 		bool                  verbose_domain_state()  const { return _verbose_domain_state; }
 		bool                  icmp_echo_server()      const { return _icmp_echo_server; }
 		Genode::Microseconds  dhcp_discover_timeout() const { return _dhcp_discover_timeout; }

repos/os/src/server/nic_router/domain.cc

@@ -205,6 +205,8 @@ Domain::Domain(Configuration &config, Xml_node const node, Allocator &alloc)
 	           Ipv4_address()),
 	_verbose_packets(_node.attribute_value("verbose_packets",
 	                                       _config.verbose_packets())),
+	_verbose_packet_drop(_node.attribute_value("verbose_packet_drop",
+	                                           _config.verbose_packet_drop())),
 	_icmp_echo_server(_node.attribute_value("icmp_echo_server",
 	                                        _config.icmp_echo_server())),
 	_label(_node.attribute_value("label", String<160>()).string())

repos/os/src/server/nic_router/domain.h

@@ -93,6 +93,7 @@ class Net::Domain : public Domain_base,
 		Genode::size_t                        _tx_bytes             { 0 };
 		Genode::size_t                        _rx_bytes             { 0 };
 		bool                            const _verbose_packets;
+		bool                            const _verbose_packet_drop;
 		bool                            const _icmp_echo_server;
 		Genode::Session_label           const _label;
 
@@ -168,6 +169,7 @@ class Net::Domain : public Domain_base,
 		 ***************/
 
 		bool                         verbose_packets()     const { return _verbose_packets; }
+		bool                         verbose_packet_drop() const { return _verbose_packet_drop; }
 		bool                         icmp_echo_server()    const { return _icmp_echo_server; }
 		Genode::Session_label const &label()               const { return _label; }
 		Ipv4_config           const &ip_config()           const { return *_ip_config; }

repos/os/src/server/nic_router/interface.cc

@@ -1177,7 +1177,7 @@ void Interface::_handle_arp_reply(Ethernet_frame &eth,
 			Arp_waiter &waiter = *waiter_le->object();
 			waiter_le = waiter_le->next();
 			if (ip != waiter.ip()) { continue; }
-			waiter.src()._continue_handle_eth(waiter.packet());
+			waiter.src()._continue_handle_eth(local_domain, waiter.packet());
 			destroy(waiter.src()._alloc, &waiter);
 		}
 	}
@@ -1284,13 +1284,14 @@ void Interface::_ready_to_submit()
 }
 
 
-void Interface::_continue_handle_eth(Packet_descriptor const &pkt)
+void Interface::_continue_handle_eth(Domain            const &domain,
+                                     Packet_descriptor const &pkt)
 {
 	Size_guard size_guard(pkt.size());
 	try { _handle_eth(_sink.packet_content(pkt), size_guard, pkt); }
 	catch (Packet_postponed) {
-		if (_config().verbose()) {
+		if (domain.verbose_packet_drop()) {
-			log("[", _domain(), "] drop packet (handling postponed twice)"); }
+			log("[", domain, "] drop packet (handling postponed twice)"); }
 	}
 	_ack_packet(pkt);
 }
@@ -1381,7 +1382,7 @@ void Interface::_handle_eth(void              *const  eth_base,
 				}
 			}
 			catch (Drop_packet exception) {
-				if (_config().verbose()) {
+				if (local_domain.verbose_packet_drop()) {
 					log("[", local_domain, "] drop packet (",
 					    exception.reason, ")");
 				}
@@ -1799,9 +1800,13 @@ void Interface::_ack_packet(Packet_descriptor const &pkt)
 
 void Interface::cancel_arp_waiting(Arp_waiter &waiter)
 {
-	if (_config().verbose()) {
+	try {
-		try { log("[", _domain(), "] drop packet (ARP got cancelled)"); }
+		Domain &domain = _domain();
+		if (domain.verbose_packet_drop()) {
+			log("[", domain, "] drop packet (ARP got cancelled)"); }
+	}
 	catch (Pointer<Domain>::Invalid) {
+		if (_config().verbose_packet_drop()) {
 			log("[?] drop packet (ARP got cancelled)"); }
 	}
 	_ack_packet(waiter.packet());

repos/os/src/server/nic_router/interface.h

@@ -239,7 +239,8 @@ class Net::Interface : private Interface_list::Element
 		              Size_guard           &size_guard,
 		              Ipv4_packet          &ip);
 
-		void _continue_handle_eth(Packet_descriptor const &pkt);
+		void _continue_handle_eth(Domain            const &domain,
+		                          Packet_descriptor const &pkt);
 
 		Ipv4_address const &_router_ip() const;