refactor: DNS

dns/transport/fakeip/memory.go

@@ -0,0 +1,89 @@
+package fakeip
+
+import (
+	"net/netip"
+	"sync"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing/common/logger"
+)
+
+var _ adapter.FakeIPStorage = (*MemoryStorage)(nil)
+
+type MemoryStorage struct {
+	addressAccess sync.RWMutex
+	domainAccess  sync.RWMutex
+	addressCache  map[netip.Addr]string
+	domainCache4  map[string]netip.Addr
+	domainCache6  map[string]netip.Addr
+}
+
+func NewMemoryStorage() *MemoryStorage {
+	return &MemoryStorage{
+		addressCache: make(map[netip.Addr]string),
+		domainCache4: make(map[string]netip.Addr),
+		domainCache6: make(map[string]netip.Addr),
+	}
+}
+
+func (s *MemoryStorage) FakeIPMetadata() *adapter.FakeIPMetadata {
+	return nil
+}
+
+func (s *MemoryStorage) FakeIPSaveMetadata(metadata *adapter.FakeIPMetadata) error {
+	return nil
+}
+
+func (s *MemoryStorage) FakeIPSaveMetadataAsync(metadata *adapter.FakeIPMetadata) {
+}
+
+func (s *MemoryStorage) FakeIPStore(address netip.Addr, domain string) error {
+	s.addressAccess.Lock()
+	s.domainAccess.Lock()
+	if oldDomain, loaded := s.addressCache[address]; loaded {
+		if address.Is4() {
+			delete(s.domainCache4, oldDomain)
+		} else {
+			delete(s.domainCache6, oldDomain)
+		}
+	}
+	s.addressCache[address] = domain
+	if address.Is4() {
+		s.domainCache4[domain] = address
+	} else {
+		s.domainCache6[domain] = address
+	}
+	s.domainAccess.Unlock()
+	s.addressAccess.Unlock()
+	return nil
+}
+
+func (s *MemoryStorage) FakeIPStoreAsync(address netip.Addr, domain string, logger logger.Logger) {
+	_ = s.FakeIPStore(address, domain)
+}
+
+func (s *MemoryStorage) FakeIPLoad(address netip.Addr) (string, bool) {
+	s.addressAccess.RLock()
+	defer s.addressAccess.RUnlock()
+	domain, loaded := s.addressCache[address]
+	return domain, loaded
+}
+
+func (s *MemoryStorage) FakeIPLoadDomain(domain string, isIPv6 bool) (netip.Addr, bool) {
+	s.domainAccess.RLock()
+	defer s.domainAccess.RUnlock()
+	if !isIPv6 {
+		address, loaded := s.domainCache4[domain]
+		return address, loaded
+	} else {
+		address, loaded := s.domainCache6[domain]
+		return address, loaded
+	}
+}
+
+func (s *MemoryStorage) FakeIPReset() error {
+	s.addressCache = make(map[netip.Addr]string)
+	s.domainCache4 = make(map[string]netip.Addr)
+	s.domainCache6 = make(map[string]netip.Addr)
+	return nil
+}