feat(tls): 新增 TLS 指纹模拟功能

backend/internal/pkg/tlsfingerprint/registry.go

@@ -0,0 +1,170 @@
+// Package tlsfingerprint provides TLS fingerprint simulation for HTTP clients.
+package tlsfingerprint
+
+import (
+	"sort"
+	"sync"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+)
+
+// DefaultProfileName is the name of the built-in Claude CLI profile.
+const DefaultProfileName = "claude_cli_v2"
+
+// Registry manages TLS fingerprint profiles.
+// It holds a collection of profiles that can be used for TLS fingerprint simulation.
+// Profiles are selected based on account ID using modulo operation.
+type Registry struct {
+	mu           sync.RWMutex
+	profiles     map[string]*Profile
+	profileNames []string // Sorted list of profile names for deterministic selection
+}
+
+// NewRegistry creates a new TLS fingerprint profile registry.
+// It initializes with the built-in default profile.
+func NewRegistry() *Registry {
+	r := &Registry{
+		profiles:     make(map[string]*Profile),
+		profileNames: make([]string, 0),
+	}
+
+	// Register the built-in default profile
+	r.registerBuiltinProfile()
+
+	return r
+}
+
+// NewRegistryFromConfig creates a new registry and loads profiles from config.
+// If the config has custom profiles defined, they will be merged with the built-in default.
+func NewRegistryFromConfig(cfg *config.TLSFingerprintConfig) *Registry {
+	r := NewRegistry()
+
+	if cfg == nil || !cfg.Enabled {
+		debugLog("[TLS Registry] TLS fingerprint disabled or no config, using default profile only")
+		return r
+	}
+
+	// Load custom profiles from config
+	for name, profileCfg := range cfg.Profiles {
+		profile := &Profile{
+			Name:         profileCfg.Name,
+			EnableGREASE: profileCfg.EnableGREASE,
+			CipherSuites: profileCfg.CipherSuites,
+			Curves:       profileCfg.Curves,
+			PointFormats: profileCfg.PointFormats,
+		}
+
+		// If the profile has empty values, they will use defaults in dialer
+		r.RegisterProfile(name, profile)
+		debugLog("[TLS Registry] Loaded custom profile: %s (%s)", name, profileCfg.Name)
+	}
+
+	debugLog("[TLS Registry] Initialized with %d profiles: %v", len(r.profileNames), r.profileNames)
+	return r
+}
+
+// registerBuiltinProfile adds the default Claude CLI profile to the registry.
+func (r *Registry) registerBuiltinProfile() {
+	defaultProfile := &Profile{
+		Name:         "Claude CLI 2.x (Node.js 20.x + OpenSSL 3.x)",
+		EnableGREASE: false, // Node.js does not use GREASE
+		// Empty slices will cause dialer to use built-in defaults
+		CipherSuites: nil,
+		Curves:       nil,
+		PointFormats: nil,
+	}
+	r.RegisterProfile(DefaultProfileName, defaultProfile)
+}
+
+// RegisterProfile adds or updates a profile in the registry.
+func (r *Registry) RegisterProfile(name string, profile *Profile) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	// Check if this is a new profile
+	_, exists := r.profiles[name]
+	r.profiles[name] = profile
+
+	if !exists {
+		r.profileNames = append(r.profileNames, name)
+		// Keep names sorted for deterministic selection
+		sort.Strings(r.profileNames)
+	}
+}
+
+// GetProfile returns a profile by name.
+// Returns nil if the profile does not exist.
+func (r *Registry) GetProfile(name string) *Profile {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	return r.profiles[name]
+}
+
+// GetDefaultProfile returns the built-in default profile.
+func (r *Registry) GetDefaultProfile() *Profile {
+	return r.GetProfile(DefaultProfileName)
+}
+
+// GetProfileByAccountID returns a profile for the given account ID.
+// The profile is selected using: profileNames[accountID % len(profiles)]
+// This ensures deterministic profile assignment for each account.
+func (r *Registry) GetProfileByAccountID(accountID int64) *Profile {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+
+	if len(r.profileNames) == 0 {
+		return nil
+	}
+
+	// Use modulo to select profile index
+	// Use absolute value to handle negative IDs (though unlikely)
+	idx := accountID
+	if idx < 0 {
+		idx = -idx
+	}
+	selectedIndex := int(idx % int64(len(r.profileNames)))
+	selectedName := r.profileNames[selectedIndex]
+
+	return r.profiles[selectedName]
+}
+
+// ProfileCount returns the number of registered profiles.
+func (r *Registry) ProfileCount() int {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	return len(r.profiles)
+}
+
+// ProfileNames returns a sorted list of all registered profile names.
+func (r *Registry) ProfileNames() []string {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+
+	// Return a copy to prevent modification
+	names := make([]string, len(r.profileNames))
+	copy(names, r.profileNames)
+	return names
+}
+
+// Global registry instance for convenience
+var globalRegistry *Registry
+var globalRegistryOnce sync.Once
+
+// GlobalRegistry returns the global TLS fingerprint registry.
+// The registry is lazily initialized with the default profile.
+func GlobalRegistry() *Registry {
+	globalRegistryOnce.Do(func() {
+		globalRegistry = NewRegistry()
+	})
+	return globalRegistry
+}
+
+// InitGlobalRegistry initializes the global registry with configuration.
+// This should be called during application startup.
+// It is safe to call multiple times; subsequent calls will update the registry.
+func InitGlobalRegistry(cfg *config.TLSFingerprintConfig) *Registry {
+	globalRegistryOnce.Do(func() {
+		globalRegistry = NewRegistryFromConfig(cfg)
+	})
+	return globalRegistry
+}