From f441648d9730e3c869049aef3f0f6ff952097db5 Mon Sep 17 00:00:00 2001
From: Philippe PITTOLI <p.pittoli@unistra.fr>
Date: Fri, 4 Oct 2019 15:59:58 +0200
Subject: [PATCH] configuration

---
 src/main.cr | 229 +++++++++++++++++++++++++++++++++-------------------
 1 file changed, 146 insertions(+), 83 deletions(-)

diff --git a/src/main.cr b/src/main.cr
index 8e04f1f..0d5160d 100644
--- a/src/main.cr
+++ b/src/main.cr
@@ -6,11 +6,22 @@ require "./colors"
 simulation = false
 file = nil
 
+prefered_network_configuration_program = nil
+prefered_dhcp_client = nil
+
 OptionParser.parse! do |parser|
 	parser.on "-s", "--simulation", "Export the network configuration." do
 		simulation = true
 	end
 
+	parser.on "-n network-configuration-program", "--net-conf network-configuration-program", "ifconfig | ip" do |prog|
+		prefered_network_configuration_program = prog
+	end
+
+	parser.on "-d dhcp-client-program", "--dhcp-client dhcp-client-program", "udhcpc" do |prog|
+		prefered_dhcp_client = prog
+	end
+
 	parser.on "-f file", "--file file", "Parse a configuration file." do |optsn|
 		file = optsn
 	end
@@ -39,10 +50,20 @@ class Do < Process
 	end
 end
 
+class NotSetup
+	def to_s(io : IO)
+		io << "not setup"
+	end
+end
+
+
 
 class NetworkCommands
-	class DHCPCommands
-		def self.dhcp(ifname : String)
+	class_property cmd_network_configuration : IfconfigCommand.class | IPCommand.class = IfconfigCommand
+	class_property cmd_dhcp_client : UDHCPCCommand.class | NotSetup.class = NotSetup
+
+	class UDHCPCCommand
+		def self.run(ifname : String)
 			# TODO: verify which dhcp client is installed on the system
 			cmd = "udhcpc"
 			unless Do.run(cmd, [ name ]).success?
@@ -51,14 +72,11 @@ class NetworkCommands
 		end
 	end
 
-	def self.which(cmd : String)
-		Do.run("which", [ cmd ]).success?
-	end
-
 	class IfconfigCommand
-		def self.interface_exists?(name : String)
+		def self.interface_exists(name : String)
 			Do.run("ifconfig", [ name ]).success?
 		end
+
 		def self.up_or_down(name : String, updown : String)
 			unless Do.run("ifconfig", [ name, updown ]).success?
 				raise "(ifconfig) Cannot set #{updown} link name #{name}"
@@ -72,14 +90,25 @@ class NetworkCommands
 		end
 
 		def self.set_ip(name : String, ip : IPAddress)
-			puts "(ip) setup static IP address"
+			unless Do.run("ifconfig", [ name, "add", ip.to_string ]).success?
+				raise "(ifconfig) Cannot set ip address #{ip.to_string} for #{name}"
+			end
+		end
+
+		# currently, aliasses with ifconfig: ifconfig add ip/mask
+		# same command as the ip setup
+		def self.set_alias(name : String, ip : IPAddress)
+			unless Do.run("ifconfig", [ name, "add", ip.to_string ]).success?
+				raise "(ifconfig) Cannot set ip address alias #{ip.to_string} for #{name}"
+			end
 		end
 	end
 
 	class IPCommand
-		def self.interface_exists?(name : String)
+		def self.interface_exists(name : String)
 			Do.run("ip", [ "link", "show", "dev", name ]).success?
 		end
+
 		def self.up_or_down(name : String, updown : String)
 			unless Do.run("ip", [ "link", "set", updown, "dev", name ]).success?
 				raise "(ip) Cannot set #{updown} link name #{name}"
@@ -93,43 +122,47 @@ class NetworkCommands
 		end
 
 		def self.set_ip(name : String, ip : IPAddress)
-			puts "(ip) setup static IP address"
+			unless Do.run("ip", [ "address", "add", ip.to_string, "dev", name ]).success?
+				raise "(ip) Cannot add ip address #{ip.to_string} to #{name}"
+			end
+		end
+
+		def self.set_alias(name : String, ip : IPAddress)
+			unless Do.run("ip", [ "address", "add", ip.to_string, "dev", name ]).success?
+				raise "(ip) Cannot add ip address alias #{ip.to_string} to #{name}"
+			end
 		end
 	end
 
 
-	def self.choose_command : IfconfigCommand.class | IPCommand.class
-		if self.which("ifconfig")
-			IfconfigCommand
-		elsif self.which("ip")
-			IPCommand
-		else
-			raise "Neither ifconfig or ip commands exists on this system"
-		end
-	end
-
-	def self.interface_exists?(name : String)
-		cmd = self.choose_command
-		cmd.interface_exists?(name)
+	def self.interface_exists(name : String)
+		@@cmd_network_configuration.interface_exists(name)
 	end
 
 	def self.up(ifname : String)
-		cmd = self.choose_command
-		cmd.up(ifname)
+		@@cmd_network_configuration.up(ifname)
 	end
 
 	def self.down(ifname : String)
-		cmd = self.choose_command
-		cmd.up(ifname)
+		@@cmd_network_configuration.up(ifname)
 	end
 
 	def self.set_ip(name : String, ip : IPAddress)
-		puts "(ip) setup static IP address"
+		@@cmd_network_configuration.set_ip name, ip
 	end
 
 	def self.dhcp(name : String)
-		puts "(ip) setup dynamic IP address"
-		DHCPCommands.dhcp name
+		cmd = @@cmd_dhcp_client
+		case cmd
+		when NotSetup
+			puts "no dhcp client: cannot perform dhcp on #{name}"
+		when UDHCPCCommand
+			cmd.run name
+		end
+	end
+
+	def self.set_alias(name : String, ip : IPAddress)
+		@@cmd_network_configuration.set_alias name, ip
 	end
 end
 
@@ -139,12 +172,6 @@ end
 #
 
 class InterfaceConfiguration
-	class NotSetup
-		def to_s(io : IO)
-			io << "not setup"
-		end
-	end
-
 	class DHCP
 		def to_s(io : IO)
 			io << "dhcp"
@@ -177,7 +204,7 @@ class InterfaceConfiguration
 
 	def to_string
 		String.build do |str|
-			if NetworkCommands.interface_exists?(@name)
+			if NetworkCommands.interface_exists(@name)
 				str << "#{CGREEN}#{@name}#{CRESET}\n"
 			else
 				str << "#{CRED}#{@name}#{CRESET}\n"
@@ -204,13 +231,10 @@ class InterfaceConfiguration
 
 	# configure the interface
 	def execute
-		unless NetworkCommands.interface_exists?(@name)
+		unless NetworkCommands.interface_exists(@name)
 			raise "The interface #{@name} doesn't exists, yet."
 		end
 
-		puts "OK on va configurer ça"
-		puts "#{self}"
-
 		if @up
 			NetworkCommands.up @name
 		else
@@ -218,50 +242,50 @@ class InterfaceConfiguration
 			return
 		end
 
+		# ipv4 configuration
+		@main_ip_v4.tap do |ip|
+			case ip
+			when IPAddress
+				NetworkCommands.set_ip @name, ip
+			when DHCP
+				NetworkCommands.dhcp @name
+			when NotSetup
+				puts "no ipv4"
+			else
+				raise "ipv4 configuration: neither static nor dynamic"
+			end
 
-		case main_ip_v4 = @main_ip_v4
-		when IPAddress
-			NetworkCommands.set_ip @name, main_ip_v4
-		when DHCP
-			NetworkCommands.dhcp @name
-		when NotSetup
-			puts "no ipv4"
-		else
-			raise "ipv4 configuration: neither static nor dynamic"
+			# We wont setup aliasses unless there is an actual IP address
+			if ip != NotSetup
+				@aliasses_v4.each do |ip_alias|
+					NetworkCommands.set_alias @name, ip_alias
+				end
+			end
 		end
 
-		case main_ip_v6 = @main_ip_v6
-		when IPAddress
-			NetworkCommands.set_ip @name, main_ip_v6
-		# TODO
-		#when Autoconfiguration
-		#	NetworkCommands.autoconfiguration @name
-		#when DHCP
-		#	NetworkCommands.dhcp6 @name
-		when NotSetup
-			puts "no ipv4"
-		else
-			raise "ipv4 configuration: neither static nor dynamic"
+		# ipv6 configuration
+		@main_ip_v6.tap do |ip|
+			case ip
+			when IPAddress
+				NetworkCommands.set_ip @name, ip
+			# TODO
+			#when Autoconfiguration
+			#	NetworkCommands.autoconfiguration @name
+			#when DHCP
+			#	NetworkCommands.dhcp6 @name
+			when NotSetup
+				puts "no ipv6"
+			else
+				raise "ipv4 configuration: neither static nor dynamic"
+			end
+
+			# We wont setup aliasses unless there is an actual IP address
+			if ip != NotSetup
+				@aliasses_v6.each do |ip_alias|
+					NetworkCommands.set_alias @name, ip_alias
+				end
+			end
 		end
-
-
-		# 	str << "\tinet #{@main_ip_v4}\n"
-
-		# 	str << "\t#{@up? "up" : "down"}\n"
-		# 	str << "\tinet #{@main_ip_v4}\n"
-
-		# 	unless @aliasses_v4.empty?
-		# 		@aliasses_v4.each do |a|
-		# 			str << "\talias #{a}\n"
-		# 		end
-		# 	end
-
-		# 	str << "\tinet6 #{@main_ip_v6}\n"
-
-		# 		@aliasses_v6.each do |a|
-		# 			str << "\talias6 #{a}\n"
-		#		end
-		# alias execution: only when the main ip address is setup
 	end
 end
 
@@ -275,8 +299,8 @@ class NetworkConfigurationParser
 
 	def self.parse (ifname : String, data : String) : InterfaceConfiguration
 		up = false
-		main_ip_v4 = InterfaceConfiguration::NotSetup.new
-		main_ip_v6 = InterfaceConfiguration::NotSetup.new
+		main_ip_v4 = NotSetup.new
+		main_ip_v6 = NotSetup.new
 
 		aliasses = [] of IPAddress
 
@@ -320,6 +344,45 @@ end
 
 Do.simulation = simulation
 
+def which(cmd : String)
+	if Process.run("which", [ cmd ]).success?
+		puts "#{cmd} installed"
+		true
+	else
+		puts "#{cmd} not installed"
+		false
+	end
+end
+
+
+#
+# discover available configuration commands
+#
+
+# ifconfig = *bsd and some linux
+# ip = linux
+possible_network_configuration_cmds = {
+	"ifconfig" => NetworkCommands::IfconfigCommand,
+	"ip"       => NetworkCommands::IPCommand
+}
+
+# udhcpc = busybox dhcp client
+possible_dhcp_clients = {
+	"udhcpc" => NetworkCommands::UDHCPCCommand
+}
+
+
+key = prefered_network_configuration_program
+key = possible_network_configuration_cmds.keys.find { |key| which(key) } if key.nil?
+# should crash if there is no network command installed
+NetworkCommands.cmd_network_configuration = possible_network_configuration_cmds[key.not_nil!]
+
+key = prefered_dhcp_client
+key = possible_dhcp_clients.keys.find { |key| which(key) } if key.nil?
+# should not crash if there is no 
+NetworkCommands.cmd_dhcp_client = possible_dhcp_clients[key] unless key.nil?
+
+
 if file.nil?
 	raise "Cannot choose files yet"
 else