Code cleaning in firewall package

client/firewall/interface/firewall.go

@@ -0,0 +1,67 @@
+package _interface
+
+import (
+	"net"
+	"net/netip"
+
+	"github.com/netbirdio/netbird/client/firewall/types"
+	"github.com/netbirdio/netbird/client/internal/statemanager"
+)
+
+// Firewall is the high level abstraction of a firewall manager
+//
+// It declares methods which handle actions required by the
+// Netbird client for ACL and routing functionality
+type Firewall interface {
+	Init(stateManager *statemanager.Manager) error
+
+	// AllowNetbird allows netbird interface traffic
+	AllowNetbird() error
+
+	// AddPeerFiltering adds a rule to the firewall
+	//
+	// If comment argument is empty firewall manager should set
+	// rule ID as comment for the rule
+	AddPeerFiltering(
+		ip net.IP,
+		proto types.Protocol,
+		sPort *types.Port,
+		dPort *types.Port,
+		action types.Action,
+		ipsetName string,
+		comment string,
+	) ([]types.Rule, error)
+
+	// DeletePeerRule from the firewall by rule definition
+	DeletePeerRule(rule types.Rule) error
+
+	// IsServerRouteSupported returns true if the firewall supports server side routing operations
+	IsServerRouteSupported() bool
+
+	AddRouteFiltering(source []netip.Prefix, destination netip.Prefix, proto types.Protocol, sPort *types.Port, dPort *types.Port, action types.Action) (types.Rule, error)
+
+	// DeleteRouteRule deletes a routing rule
+	DeleteRouteRule(rule types.Rule) error
+
+	// AddNatRule inserts a routing NAT rule
+	AddNatRule(pair types.RouterPair) error
+
+	// RemoveNatRule removes a routing NAT rule
+	RemoveNatRule(pair types.RouterPair) error
+
+	// SetLegacyManagement sets the legacy management mode
+	SetLegacyManagement(legacy bool) error
+
+	// Reset firewall to the default state
+	Reset(stateManager *statemanager.Manager) error
+
+	// Flush the changes to firewall controller
+	Flush() error
+
+	// AddDNATRule adds a DNAT rule
+	AddDNATRule(types.ForwardRule) (types.Rule, error)
+
+	// DeleteDNATRule deletes a DNAT rule
+	// todo: do you need a string ID or the complete rule?
+	DeleteDNATRule(types.Rule) error
+}