feat: move filters into a sub-package

These really don't belong in the root package.

Author: Stebalien

Diff for: filter.go renamed to filter/filter.go

@@ -1,8 +1,10 @@
-package multiaddr
+package filter
 
 import (
 	"net"
 	"sync"
+
+	ma "github.com/multiformats/go-multiaddr"
 )
 
 // Action is an enum modelling all possible filter actions.
@@ -108,17 +110,17 @@ func (fs *Filters) RemoveLiteral(ipnet net.IPNet) (removed bool) {
 // TODO: currently, the last filter to match wins always, but it shouldn't be that way.
 //  Instead, the highest-specific last filter should win; that way more specific filters
 //  override more general ones.
-func (fs *Filters) AddrBlocked(a Multiaddr) (deny bool) {
+func (fs *Filters) AddrBlocked(a ma.Multiaddr) (deny bool) {
 	var (
 		netip net.IP
 		found bool
 	)
 
-	ForEach(a, func(c Component) bool {
+	ma.ForEach(a, func(c ma.Component) bool {
 		switch c.Protocol().Code {
-		case P_IP6ZONE:
+		case ma.P_IP6ZONE:
 			return true
-		case P_IP6, P_IP4:
+		case ma.P_IP6, ma.P_IP4:
 			found = true
 			netip = net.IP(c.RawValue())
 			return false

Diff for: filter_test.go renamed to filter/filter_test.go

@@ -1,4 +1,4 @@
-package multiaddr
+package filter
 
 import (
 	"net"
@@ -66,7 +66,7 @@ func TestFilterBlocking(t *testing.T) {
 		"/ip6/fd00::2/tcp/321",
 		"/ip6/fc00::1/udp/321",
 	} {
-		maddr, err := NewMultiaddr(blocked)
+		maddr, err := ma.NewMultiaddr(blocked)
 		if err != nil {
 			t.Error(err)
 		}