处理权限逻辑

Tun/Context/SDLContextActor.swift

@@ -358,7 +358,7 @@ extension SDLContextActor {
 
         let updatePolicyWorker = PeriodicWorker(
             configuration: .init(
-                interval: .seconds(120),
+                interval: .seconds(10),
                 runImmediately: true,
                 mode: .fixedDelay,
                 errorPolicy: .keepRunning(delay: .seconds(5))

Tun/Policy/PolicyRuleStore.swift

@@ -9,54 +9,55 @@ import NIO
 
 actor PolicyRuleStore {
 
-    // 处理权限的请求问题
-    nonisolated private let cooldown: Duration = .seconds(5)
-    // identityId
-    private var coolingDown: Set<UInt32> = []
+    private struct PolicyEntry {
+        let ruleMap: PolicyRuleMap
+        let expiresAt: TimeInterval
+    }
+
+    private struct PendingRequest {
+        let version: UInt32
+        let retryCount: Int
+        let nextRetryAt: TimeInterval
+    }
+
+    private let policyTTL: TimeInterval = 120
+    private let refreshLeadTime: TimeInterval = 15
+    private let baseRetryDelay: TimeInterval = 2
+    private let maxRetryDelay: TimeInterval = 60
+
     // 处理各个请求的版本问题, map[identityId] = version
     private var versions: [UInt32: UInt32] = [:]
+    private var pendingByIdentity: [UInt32: PendingRequest] = [:]
     
     nonisolated private let alloctor = ByteBufferAllocator()
     
     private let publisher: SnapshotPublisher<PolicyRuleSnapshot>
-    private var ruleMapByIdentity: [UInt32: PolicyRuleMap] = [:]
+    private var policyByIdentity: [UInt32: PolicyEntry] = [:]
     
     init(publisher: SnapshotPublisher<PolicyRuleSnapshot>) {
         self.publisher = publisher
     }
 
     func makeBatchPolicyRequests(dstIdentityID: UInt32) -> [Data] {
-        return self.ruleMapByIdentity.keys.compactMap { identityId in
-            var policyRequest = SDLPolicyRequest()
-            policyRequest.srcIdentityID = identityId
-            policyRequest.dstIdentityID = dstIdentityID
-            policyRequest.version = self.nextVersion(identityId: identityId)
-            return try? policyRequest.serializedData()
+        let now = Date().timeIntervalSince1970
+        let identities = Set(self.policyByIdentity.keys).union(self.pendingByIdentity.keys)
+
+        return identities.compactMap { identityId in
+            self.makePolicyRequestIfDue(srcIdentityId: identityId, dstIdentityId: dstIdentityID, now: now, forceMissing: false)
         }
     }
 
     func makePolicyRequest(srcIdentityId: UInt32, dstIdentityId: UInt32) -> Data? {
-        guard self.ruleMapByIdentity[srcIdentityId] == nil else {
+        guard self.policyByIdentity[srcIdentityId] == nil else {
             return nil
         }
 
-        guard !coolingDown.contains(srcIdentityId) else {
-            return nil
-        }
-
-        var policyRequest = SDLPolicyRequest()
-        policyRequest.srcIdentityID = srcIdentityId
-        policyRequest.dstIdentityID = dstIdentityId
-        policyRequest.version = self.nextVersion(identityId: srcIdentityId)
-
-        coolingDown.insert(srcIdentityId)
-
-        Task { [weak self] in
-            try? await Task.sleep(for: .seconds(5))
-            await self?.endCooldown(for: srcIdentityId)
-        }
-
-        return try? policyRequest.serializedData()
+        return self.makePolicyRequestIfDue(
+            srcIdentityId: srcIdentityId,
+            dstIdentityId: dstIdentityId,
+            now: Date().timeIntervalSince1970,
+            forceMissing: true
+        )
     }
     
     // 处理权限的响应
@@ -64,7 +65,11 @@ actor PolicyRuleStore {
         let id = policyResponse.srcIdentityID
         let version = policyResponse.version
         
-        guard self.ruleMapByIdentity[id] == nil || ((self.ruleMapByIdentity[id]?.version ?? 0) < version) else {
+        if let pending = self.pendingByIdentity[id], pending.version <= version {
+            self.pendingByIdentity.removeValue(forKey: id)
+        }
+
+        guard self.policyByIdentity[id] == nil || ((self.policyByIdentity[id]?.ruleMap.version ?? 0) < version) else {
             return
         }
         
@@ -78,7 +83,11 @@ actor PolicyRuleStore {
             }
             ruleMap[proto, default: [:]][port] = true
         }
-        self.ruleMapByIdentity[id] = PolicyRuleMap(version: version, ruleMap: ruleMap)
+        let now = Date().timeIntervalSince1970
+        self.policyByIdentity[id] = PolicyEntry(
+            ruleMap: PolicyRuleMap(version: version, ruleMap: ruleMap),
+            expiresAt: now + self.policyTTL
+        )
         SDLLogger.log("[PolicyRuleStore] apply policy response, srcIdentityID: \(id), version: \(version), rulesCount: \(ruleMap.reduce(0) { $0 + $1.value.count })", for: .debug)
         
         // 发布新的快照信息
@@ -87,18 +96,14 @@ actor PolicyRuleStore {
     }
 
     func clear() {
-        self.coolingDown.removeAll()
         self.versions.removeAll()
-        self.ruleMapByIdentity.removeAll()
+        self.pendingByIdentity.removeAll()
+        self.policyByIdentity.removeAll()
         self.publisher.publish(PolicyRuleSnapshot.empty())
     }
     
     private func compileSnapshot() -> PolicyRuleSnapshot {
-        return PolicyRuleSnapshot(ruleMapByIdentity: ruleMapByIdentity)
-    }
-
-    private func endCooldown(for key: UInt32) {
-        self.coolingDown.remove(key)
+        return PolicyRuleSnapshot(ruleMapByIdentity: self.policyByIdentity.mapValues(\.ruleMap))
     }
     
     private func nextVersion(identityId: UInt32) -> UInt32 {
@@ -108,4 +113,46 @@ actor PolicyRuleStore {
         
         return version
     }
+
+    private func makePolicyRequestIfDue(srcIdentityId: UInt32, dstIdentityId: UInt32, now: TimeInterval, forceMissing: Bool) -> Data? {
+        if let pending = self.pendingByIdentity[srcIdentityId], pending.nextRetryAt > now {
+            return nil
+        }
+
+        if !forceMissing,
+           let entry = self.policyByIdentity[srcIdentityId],
+           entry.expiresAt - self.refreshLeadTime > now {
+            return nil
+        }
+
+        let version = self.nextVersion(identityId: srcIdentityId)
+        guard let data = self.makePolicyRequestData(srcIdentityId: srcIdentityId, dstIdentityId: dstIdentityId, version: version) else {
+            return nil
+        }
+
+        let retryCount = self.pendingByIdentity[srcIdentityId].map { $0.retryCount + 1 } ?? 0
+        let retryDelay = self.retryDelay(for: retryCount, identityId: srcIdentityId)
+        self.pendingByIdentity[srcIdentityId] = PendingRequest(
+            version: version,
+            retryCount: retryCount,
+            nextRetryAt: now + retryDelay
+        )
+
+        return data
+    }
+
+    private func makePolicyRequestData(srcIdentityId: UInt32, dstIdentityId: UInt32, version: UInt32) -> Data? {
+        var policyRequest = SDLPolicyRequest()
+        policyRequest.srcIdentityID = srcIdentityId
+        policyRequest.dstIdentityID = dstIdentityId
+        policyRequest.version = version
+        return try? policyRequest.serializedData()
+    }
+
+    private func retryDelay(for retryCount: Int, identityId: UInt32) -> TimeInterval {
+        let cappedRetryCount = min(retryCount, 5)
+        let multiplier = Double(1 << cappedRetryCount)
+        let jitter = Double(identityId % 1_000) / 1_000
+        return min(self.baseRetryDelay * multiplier + jitter, self.maxRetryDelay)
+    }
 }