First Commmit

2026-04-14 22:41:14 +08:00
commit 9f867b19da
1086 changed files with 147554 additions and 0 deletions
--- a/experimental/cachefile/dns_cache.go
+++ b/experimental/cachefile/dns_cache.go
@@ -0,0 +1,299 @@
+package cachefile
+
+import (
+	"encoding/binary"
+	"time"
+
+	"github.com/sagernet/bbolt"
+	"github.com/sagernet/sing/common/buf"
+	"github.com/sagernet/sing/common/logger"
+)
+
+var bucketDNSCache = []byte("dns_cache")
+
+func (c *CacheFile) StoreDNS() bool {
+	return c.storeDNS
+}
+
+func (c *CacheFile) LoadDNSCache(transportName string, qName string, qType uint16) (rawMessage []byte, expireAt time.Time, loaded bool) {
+	c.saveDNSCacheAccess.RLock()
+	entry, cached := c.saveDNSCache[saveCacheKey{transportName, qName, qType}]
+	c.saveDNSCacheAccess.RUnlock()
+	if cached {
+		return entry.rawMessage, entry.expireAt, true
+	}
+	key := buf.Get(2 + len(qName))
+	binary.BigEndian.PutUint16(key, qType)
+	copy(key[2:], qName)
+	defer buf.Put(key)
+	err := c.view(func(tx *bbolt.Tx) error {
+		bucket := c.bucket(tx, bucketDNSCache)
+		if bucket == nil {
+			return nil
+		}
+		bucket = bucket.Bucket([]byte(transportName))
+		if bucket == nil {
+			return nil
+		}
+		content := bucket.Get(key)
+		if len(content) < 8 {
+			return nil
+		}
+		expireAt = time.Unix(int64(binary.BigEndian.Uint64(content[:8])), 0)
+		rawMessage = make([]byte, len(content)-8)
+		copy(rawMessage, content[8:])
+		loaded = true
+		return nil
+	})
+	if err != nil {
+		return nil, time.Time{}, false
+	}
+	return
+}
+
+func (c *CacheFile) SaveDNSCache(transportName string, qName string, qType uint16, rawMessage []byte, expireAt time.Time) error {
+	return c.batch(func(tx *bbolt.Tx) error {
+		bucket, err := c.createBucket(tx, bucketDNSCache)
+		if err != nil {
+			return err
+		}
+		bucket, err = bucket.CreateBucketIfNotExists([]byte(transportName))
+		if err != nil {
+			return err
+		}
+		key := buf.Get(2 + len(qName))
+		binary.BigEndian.PutUint16(key, qType)
+		copy(key[2:], qName)
+		defer buf.Put(key)
+		value := buf.Get(8 + len(rawMessage))
+		defer buf.Put(value)
+		binary.BigEndian.PutUint64(value[:8], uint64(expireAt.Unix()))
+		copy(value[8:], rawMessage)
+		return bucket.Put(key, value)
+	})
+}
+
+func (c *CacheFile) SaveDNSCacheAsync(transportName string, qName string, qType uint16, rawMessage []byte, expireAt time.Time, logger logger.Logger) {
+	saveKey := saveCacheKey{transportName, qName, qType}
+	if !c.queueDNSCacheSave(saveKey, rawMessage, expireAt) {
+		return
+	}
+	go c.flushPendingDNSCache(saveKey, logger)
+}
+
+func (c *CacheFile) queueDNSCacheSave(saveKey saveCacheKey, rawMessage []byte, expireAt time.Time) bool {
+	c.saveDNSCacheAccess.Lock()
+	defer c.saveDNSCacheAccess.Unlock()
+	entry := c.saveDNSCache[saveKey]
+	entry.rawMessage = append([]byte(nil), rawMessage...)
+	entry.expireAt = expireAt
+	entry.sequence++
+	startFlush := !entry.saving
+	entry.saving = true
+	c.saveDNSCache[saveKey] = entry
+	return startFlush
+}
+
+func (c *CacheFile) flushPendingDNSCache(saveKey saveCacheKey, logger logger.Logger) {
+	c.flushPendingDNSCacheWith(saveKey, logger, func(entry saveDNSCacheEntry) error {
+		return c.SaveDNSCache(saveKey.TransportName, saveKey.QuestionName, saveKey.QType, entry.rawMessage, entry.expireAt)
+	})
+}
+
+func (c *CacheFile) flushPendingDNSCacheWith(saveKey saveCacheKey, logger logger.Logger, save func(saveDNSCacheEntry) error) {
+	for {
+		c.saveDNSCacheAccess.RLock()
+		entry, loaded := c.saveDNSCache[saveKey]
+		c.saveDNSCacheAccess.RUnlock()
+		if !loaded {
+			return
+		}
+		err := save(entry)
+		if err != nil {
+			logger.Warn("save DNS cache: ", err)
+		}
+		c.saveDNSCacheAccess.Lock()
+		currentEntry, loaded := c.saveDNSCache[saveKey]
+		if !loaded {
+			c.saveDNSCacheAccess.Unlock()
+			return
+		}
+		if currentEntry.sequence != entry.sequence {
+			c.saveDNSCacheAccess.Unlock()
+			continue
+		}
+		delete(c.saveDNSCache, saveKey)
+		c.saveDNSCacheAccess.Unlock()
+		return
+	}
+}
+
+func (c *CacheFile) ClearDNSCache() error {
+	c.saveDNSCacheAccess.Lock()
+	clear(c.saveDNSCache)
+	c.saveDNSCacheAccess.Unlock()
+	return c.batch(func(tx *bbolt.Tx) error {
+		if c.cacheID == nil {
+			bucket := tx.Bucket(bucketDNSCache)
+			if bucket == nil {
+				return nil
+			}
+			return tx.DeleteBucket(bucketDNSCache)
+		}
+		bucket := tx.Bucket(c.cacheID)
+		if bucket == nil || bucket.Bucket(bucketDNSCache) == nil {
+			return nil
+		}
+		return bucket.DeleteBucket(bucketDNSCache)
+	})
+}
+
+func (c *CacheFile) loopCacheCleanup(interval time.Duration, cleanupFunc func()) {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-c.ctx.Done():
+			return
+		case <-ticker.C:
+			cleanupFunc()
+		}
+	}
+}
+
+func (c *CacheFile) cleanupDNSCache() {
+	now := time.Now()
+	err := c.batch(func(tx *bbolt.Tx) error {
+		bucket := c.bucket(tx, bucketDNSCache)
+		if bucket == nil {
+			return nil
+		}
+		var emptyTransports [][]byte
+		err := bucket.ForEachBucket(func(transportName []byte) error {
+			transportBucket := bucket.Bucket(transportName)
+			if transportBucket == nil {
+				return nil
+			}
+			var expiredKeys [][]byte
+			err := transportBucket.ForEach(func(key, value []byte) error {
+				if len(value) < 8 {
+					expiredKeys = append(expiredKeys, append([]byte(nil), key...))
+					return nil
+				}
+				if c.disableExpire {
+					return nil
+				}
+				expireAt := time.Unix(int64(binary.BigEndian.Uint64(value[:8])), 0)
+				if now.After(expireAt.Add(c.optimisticTimeout)) {
+					expiredKeys = append(expiredKeys, append([]byte(nil), key...))
+				}
+				return nil
+			})
+			if err != nil {
+				return err
+			}
+			for _, key := range expiredKeys {
+				err = transportBucket.Delete(key)
+				if err != nil {
+					return err
+				}
+			}
+			first, _ := transportBucket.Cursor().First()
+			if first == nil {
+				emptyTransports = append(emptyTransports, append([]byte(nil), transportName...))
+			}
+			return nil
+		})
+		if err != nil {
+			return err
+		}
+		for _, name := range emptyTransports {
+			err = bucket.DeleteBucket(name)
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		c.logger.Warn("cleanup DNS cache: ", err)
+	}
+}
+
+func (c *CacheFile) clearRDRC() {
+	c.saveRDRCAccess.Lock()
+	clear(c.saveRDRC)
+	c.saveRDRCAccess.Unlock()
+	err := c.batch(func(tx *bbolt.Tx) error {
+		if c.cacheID == nil {
+			if tx.Bucket(bucketRDRC) == nil {
+				return nil
+			}
+			return tx.DeleteBucket(bucketRDRC)
+		}
+		bucket := tx.Bucket(c.cacheID)
+		if bucket == nil || bucket.Bucket(bucketRDRC) == nil {
+			return nil
+		}
+		return bucket.DeleteBucket(bucketRDRC)
+	})
+	if err != nil {
+		c.logger.Warn("clear RDRC: ", err)
+	}
+}
+
+func (c *CacheFile) cleanupRDRC() {
+	now := time.Now()
+	err := c.batch(func(tx *bbolt.Tx) error {
+		bucket := c.bucket(tx, bucketRDRC)
+		if bucket == nil {
+			return nil
+		}
+		var emptyTransports [][]byte
+		err := bucket.ForEachBucket(func(transportName []byte) error {
+			transportBucket := bucket.Bucket(transportName)
+			if transportBucket == nil {
+				return nil
+			}
+			var expiredKeys [][]byte
+			err := transportBucket.ForEach(func(key, value []byte) error {
+				if len(value) < 8 {
+					expiredKeys = append(expiredKeys, append([]byte(nil), key...))
+					return nil
+				}
+				expiresAt := time.Unix(int64(binary.BigEndian.Uint64(value)), 0)
+				if now.After(expiresAt) {
+					expiredKeys = append(expiredKeys, append([]byte(nil), key...))
+				}
+				return nil
+			})
+			if err != nil {
+				return err
+			}
+			for _, key := range expiredKeys {
+				err = transportBucket.Delete(key)
+				if err != nil {
+					return err
+				}
+			}
+			first, _ := transportBucket.Cursor().First()
+			if first == nil {
+				emptyTransports = append(emptyTransports, append([]byte(nil), transportName...))
+			}
+			return nil
+		})
+		if err != nil {
+			return err
+		}
+		for _, name := range emptyTransports {
+			err = bucket.DeleteBucket(name)
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		c.logger.Warn("cleanup RDRC: ", err)
+	}
+}