massive refactoring for interoperability

policy.go

@@ -0,0 +1,117 @@
+package core
+
+import (
+	"sync"
+	"time"
+)
+
+// TimeoutPolicy contains limits for connection timeout.
+type TimeoutPolicy struct {
+	// Timeout for handshake phase in a connection.
+	Handshake time.Duration
+	// Timeout for connection being idle, i.e., there is no egress or ingress traffic in this connection.
+	ConnectionIdle time.Duration
+	// Timeout for an uplink only connection, i.e., the downlink of the connection has ben closed.
+	UplinkOnly time.Duration
+	// Timeout for an downlink only connection, i.e., the uplink of the connection has ben closed.
+	DownlinkOnly time.Duration
+}
+
+// OverrideWith overrides the current TimeoutPolicy with another one. All timeouts with zero value will be overridden with the new value.
+func (p TimeoutPolicy) OverrideWith(another TimeoutPolicy) TimeoutPolicy {
+	if p.Handshake == 0 {
+		p.Handshake = another.Handshake
+	}
+	if p.ConnectionIdle == 0 {
+		p.ConnectionIdle = another.ConnectionIdle
+	}
+	if p.UplinkOnly == 0 {
+		p.UplinkOnly = another.UplinkOnly
+	}
+	if p.DownlinkOnly == 0 {
+		p.DownlinkOnly = another.DownlinkOnly
+	}
+	return p
+}
+
+// Policy is session based settings for controlling V2Ray requests. It contains various settings (or limits) that may differ for different users in the context.
+type Policy struct {
+	Timeouts TimeoutPolicy // Timeout settings
+}
+
+// OverrideWith overrides the current Policy with another one. All values with default value will be overridden.
+func (p Policy) OverrideWith(another Policy) Policy {
+	p.Timeouts.OverrideWith(another.Timeouts)
+	return p
+}
+
+// PolicyManager is a feature that provides Policy for the given user by its id or level.
+type PolicyManager interface {
+	Feature
+
+	// ForLevel returns the Policy for the given user level.
+	ForLevel(level uint32) Policy
+}
+
+// DefaultPolicy returns the Policy when user is not specified.
+func DefaultPolicy() Policy {
+	return Policy{
+		Timeouts: TimeoutPolicy{
+			Handshake:      time.Second * 4,
+			ConnectionIdle: time.Second * 300,
+			UplinkOnly:     time.Second * 5,
+			DownlinkOnly:   time.Second * 30,
+		},
+	}
+}
+
+type syncPolicyManager struct {
+	sync.RWMutex
+	PolicyManager
+}
+
+func (m *syncPolicyManager) ForLevel(level uint32) Policy {
+	m.RLock()
+	defer m.RUnlock()
+
+	if m.PolicyManager == nil {
+		p := DefaultPolicy()
+		if level == 1 {
+			p.Timeouts.ConnectionIdle = time.Second * 600
+		}
+		return p
+	}
+
+	return m.PolicyManager.ForLevel(level)
+}
+
+func (m *syncPolicyManager) Start() error {
+	m.RLock()
+	defer m.RUnlock()
+
+	if m.PolicyManager == nil {
+		return nil
+	}
+
+	return m.PolicyManager.Start()
+}
+
+func (m *syncPolicyManager) Close() {
+	m.RLock()
+	defer m.RUnlock()
+
+	if m.PolicyManager != nil {
+		m.PolicyManager.Close()
+	}
+}
+
+func (m *syncPolicyManager) Set(manager PolicyManager) {
+	if manager == nil {
+		return
+	}
+
+	m.Lock()
+	defer m.Unlock()
+
+	m.PolicyManager = manager
+}