NetworkServer: Add a new NetworkServer service

This service is responsible for loading network configuration from a
/etc/Network.ini config file. It sets up static IP address + mask or
starts DHCPClient depending on configuration.

Base/etc/Network.ini

@@ -0,0 +1,5 @@
+[ep1s0]
+Enabled=false
+
+[ep0s8]
+DHCP=true

Base/etc/SystemServer.ini

@@ -51,6 +51,10 @@ SystemModes=text,graphical
 MultiInstance=true
 AcceptSocketConnections=true
 
+[NetworkServer]
+User=root
+SystemModes=text,graphical,self-test
+
 [LookupServer]
 Socket=/tmp/portal/lookup
 SocketPermissions=660
@@ -59,12 +63,6 @@ KeepAlive=true
 User=lookup
 SystemModes=text,graphical,self-test,generate-manpages
 
-[DHCPClient]
-Priority=low
-KeepAlive=true
-User=root
-SystemModes=text,graphical,self-test
-
 [NotificationServer]
 Socket=/tmp/portal/notify
 SocketPermissions=600

Userland/Services/CMakeLists.txt

@@ -13,6 +13,7 @@ add_subdirectory(KeyboardPreferenceLoader)
 add_subdirectory(LaunchServer)
 add_subdirectory(LoginServer)
 add_subdirectory(LookupServer)
+add_subdirectory(NetworkServer)
 add_subdirectory(NotificationServer)
 add_subdirectory(RequestServer)
 add_subdirectory(SQLServer)

Userland/Services/NetworkServer/CMakeLists.txt

@@ -0,0 +1,12 @@
+serenity_component(
+ NetworkServer
+ REQUIRED
+ TARGETS NetworkServer
+)
+
+set(SOURCES
+ main.cpp
+)
+
+serenity_bin(NetworkServer)
+target_link_libraries(NetworkServer LibCore LibConfig LibMain)

Userland/Services/NetworkServer/main.cpp

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2022, Maciej <[email protected]>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/JsonArray.h>
+#include <AK/JsonObject.h>
+#include <AK/JsonParser.h>
+#include <LibCore/Command.h>
+#include <LibCore/ConfigFile.h>
+#include <LibCore/EventLoop.h>
+#include <LibCore/File.h>
+#include <LibCore/System.h>
+#include <LibMain/Main.h>
+#include <unistd.h>
+
+ErrorOr<int> serenity_main(Main::Arguments)
+{
+ TRY(Core::System::pledge("stdio recvfd sendfd rpath unix exec proc"));
+ TRY(Core::System::unveil("/proc/net", "r"));
+ TRY(Core::System::unveil("/bin/DHCPClient", "x"));
+ TRY(Core::System::unveil("/etc/Network.ini", "r"));
+ TRY(Core::System::unveil("/bin/ifconfig", "x"));
+ TRY(Core::System::unveil(nullptr, nullptr));
+
+ auto config_file = TRY(Core::ConfigFile::open_for_system("Network"));
+
+ // FIXME: Port this to Core::Stream when it gets read_all.
+ auto proc_net_adapters_file = TRY(Core::File::open("/proc/net/adapters", Core::OpenMode::ReadOnly));
+ auto data = proc_net_adapters_file->read_all();
+ JsonParser parser(data);
+ JsonValue proc_net_adapters_json = TRY(parser.parse());
+
+ auto groups = config_file->groups();
+ dbgln("Interfaces to configure: {}", groups);
+
+ struct InterfaceConfig {
+ bool enabled = false;
+ bool dhcp_enabled = false;
+ String ipv4_address = "0.0.0.0";
+ String ipv4_netmask = "0.0.0.0";
+ };
+
+ Vector<String> interfaces_with_dhcp_enabled;
+ proc_net_adapters_json.as_array().for_each([&](auto& value) {
+ auto& if_object = value.as_object();
+ auto ifname = if_object.get("name").to_string();
+
+ if (ifname == "loop")
+ return;
+
+ InterfaceConfig config;
+ if (!groups.contains_slow(ifname)) {
+ dbgln("Config for interface {} doesn't exist, not enabling it", ifname);
+ } else {
+ config.enabled = config_file->read_bool_entry(ifname, "Enabled", true);
+ config.dhcp_enabled = config_file->read_bool_entry(ifname, "DHCP", false);
+ if (!config.dhcp_enabled) {
+ config.ipv4_address = config_file->read_entry(ifname, "IPv4Address", "0.0.0.0");
+ config.ipv4_netmask = config_file->read_entry(ifname, "IPv4Netmask", "0.0.0.0");
+ }
+ }
+ if (config.enabled) {
+ if (config.dhcp_enabled)
+ interfaces_with_dhcp_enabled.append(ifname);
+ else {
+ // FIXME: Propagate errors
+ // FIXME: Do this asynchronously
+ dbgln("Setting up interface {} statically ({}/{})", ifname, config.ipv4_address, config.ipv4_netmask);
+ MUST(Core::command("ifconfig", { "-a", ifname.characters(), "-i", config.ipv4_address.characters(), "-m", config.ipv4_netmask.characters() }, {}));
+ }
+ }
+ });
+ if (!interfaces_with_dhcp_enabled.is_empty()) {
+ dbgln("Running DHCPClient for interfaces: {}", interfaces_with_dhcp_enabled);
+ Vector<char*> args;
+ char dhcp_client_arg[] = "DHCPClient";
+ args.append(dhcp_client_arg);
+ for (auto& iface : interfaces_with_dhcp_enabled)
+ args.append(const_cast<char*>(iface.characters()));
+ args.append(nullptr);
+ auto dhcp_client_pid = TRY(Core::System::posix_spawnp("DHCPClient", nullptr, nullptr, args.data(), environ));
+ TRY(Core::System::disown(dhcp_client_pid));
+ }
+ return 0;
+}