feat(tls): 新增 TLS 指纹模拟功能

backend/internal/config/config.go

@@ -259,6 +259,33 @@ type GatewayConfig struct {
 
 	// Scheduling: 账号调度相关配置
 	Scheduling GatewaySchedulingConfig `mapstructure:"scheduling"`
+
+	// TLSFingerprint: TLS指纹伪装配置
+	TLSFingerprint TLSFingerprintConfig `mapstructure:"tls_fingerprint"`
+}
+
+// TLSFingerprintConfig TLS指纹伪装配置
+// 用于模拟 Claude CLI (Node.js) 的 TLS 握手特征，避免被识别为非官方客户端
+type TLSFingerprintConfig struct {
+	// Enabled: 是否全局启用TLS指纹功能
+	Enabled bool `mapstructure:"enabled"`
+	// Profiles: 预定义的TLS指纹配置模板
+	// key 为模板名称，如 "claude_cli_v2", "chrome_120" 等
+	Profiles map[string]TLSProfileConfig `mapstructure:"profiles"`
+}
+
+// TLSProfileConfig 单个TLS指纹模板的配置
+type TLSProfileConfig struct {
+	// Name: 模板显示名称
+	Name string `mapstructure:"name"`
+	// EnableGREASE: 是否启用GREASE扩展（Chrome使用，Node.js不使用）
+	EnableGREASE bool `mapstructure:"enable_grease"`
+	// CipherSuites: TLS加密套件列表（空则使用内置默认值）
+	CipherSuites []uint16 `mapstructure:"cipher_suites"`
+	// Curves: 椭圆曲线列表（空则使用内置默认值）
+	Curves []uint16 `mapstructure:"curves"`
+	// PointFormats: 点格式列表（空则使用内置默认值）
+	PointFormats []uint8 `mapstructure:"point_formats"`
 }
 
 // GatewaySchedulingConfig accounts scheduling configuration.
@@ -787,6 +814,8 @@ func setDefaults() {
 	viper.SetDefault("gateway.scheduling.outbox_lag_rebuild_failures", 3)
 	viper.SetDefault("gateway.scheduling.outbox_backlog_rebuild_rows", 10000)
 	viper.SetDefault("gateway.scheduling.full_rebuild_interval_seconds", 300)
+	// TLS指纹伪装配置（默认关闭，需要账号级别单独启用）
+	viper.SetDefault("gateway.tls_fingerprint.enabled", true)
 	viper.SetDefault("concurrency.ping_interval", 10)
 
 	// TokenRefresh

backend/internal/handler/dto/mappers.go

@@ -161,6 +161,11 @@ func AccountFromServiceShallow(a *service.Account) *Account {
 		if idleTimeout := a.GetSessionIdleTimeoutMinutes(); idleTimeout > 0 {
 			out.SessionIdleTimeoutMin = &idleTimeout
 		}
+		// TLS指纹伪装开关
+		if a.IsTLSFingerprintEnabled() {
+			enabled := true
+			out.EnableTLSFingerprint = &enabled
+		}
 	}
 
 	return out

backend/internal/handler/dto/types.go

@@ -112,6 +112,10 @@ type Account struct {
 	MaxSessions           *int `json:"max_sessions,omitempty"`
 	SessionIdleTimeoutMin *int `json:"session_idle_timeout_minutes,omitempty"`
 
+	// TLS指纹伪装（仅 Anthropic OAuth/SetupToken 账号有效）
+	// 从 extra 字段提取，方便前端显示和编辑
+	EnableTLSFingerprint *bool `json:"enable_tls_fingerprint,omitempty"`
+
 	Proxy         *Proxy         `json:"proxy,omitempty"`
 	AccountGroups []AccountGroup `json:"account_groups,omitempty"`
 

backend/internal/pkg/tlsfingerprint/dialer.go

+// Package tlsfingerprint provides TLS fingerprint simulation for HTTP clients.
+// It uses the utls library to create TLS connections that mimic Node.js/Claude Code clients.
+package tlsfingerprint
+
+import (
+	"bufio"
+	"context"
+	"encoding/base64"
+	"fmt"
+	"log"
+	"net"
+	"net/http"
+	"net/url"
+
+	"github.com/gin-gonic/gin"
+	utls "github.com/refraction-networking/utls"
+	"golang.org/x/net/proxy"
+)
+
+// debugLog prints log only in non-release mode.
+func debugLog(format string, v ...any) {
+	if gin.Mode() != gin.ReleaseMode {
+		log.Printf(format, v...)
+	}
+}
+
+// Profile contains TLS fingerprint configuration.
+type Profile struct {
+	Name         string // Profile name for identification
+	CipherSuites []uint16
+	Curves       []uint16
+	PointFormats []uint8
+	EnableGREASE bool
+}
+
+// Dialer creates TLS connections with custom fingerprints.
+type Dialer struct {
+	profile    *Profile
+	baseDialer func(ctx context.Context, network, addr string) (net.Conn, error)
+}
+
+// HTTPProxyDialer creates TLS connections through HTTP/HTTPS proxies with custom fingerprints.
+// It handles the CONNECT tunnel establishment before performing TLS handshake.
+type HTTPProxyDialer struct {
+	profile  *Profile
+	proxyURL *url.URL
+}
+
+// SOCKS5ProxyDialer creates TLS connections through SOCKS5 proxies with custom fingerprints.
+// It uses golang.org/x/net/proxy to establish the SOCKS5 tunnel.
+type SOCKS5ProxyDialer struct {
+	profile  *Profile
+	proxyURL *url.URL
+}
+
+// Default TLS fingerprint values captured from Claude CLI 2.x (Node.js 20.x + OpenSSL 3.x)
+// Captured using: tshark -i lo -f "tcp port 8443" -Y "tls.handshake.type == 1" -V
+// JA3 Hash: 1a28e69016765d92e3b381168d68922c
+//
+// Note: JA3/JA4 may have slight variations due to:
+// - Session ticket presence/absence
+// - Extension negotiation state
+var (
+	// defaultCipherSuites contains all 59 cipher suites from Claude CLI
+	// Order is critical for JA3 fingerprint matching
+	defaultCipherSuites = []uint16{
+		// TLS 1.3 cipher suites (MUST be first)
+		0x1302, // TLS_AES_256_GCM_SHA384
+		0x1303, // TLS_CHACHA20_POLY1305_SHA256
+		0x1301, // TLS_AES_128_GCM_SHA256
+
+		// ECDHE + AES-GCM
+		0xc02f, // TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
+		0xc02b, // TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
+		0xc030, // TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
+		0xc02c, // TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
+
+		// DHE + AES-GCM
+		0x009e, // TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
+
+		// ECDHE/DHE + AES-CBC-SHA256/384
+		0xc027, // TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
+		0x0067, // TLS_DHE_RSA_WITH_AES_128_CBC_SHA256
+		0xc028, // TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
+		0x006b, // TLS_DHE_RSA_WITH_AES_256_CBC_SHA256
+
+		// DHE-DSS/RSA + AES-GCM
+		0x00a3, // TLS_DHE_DSS_WITH_AES_256_GCM_SHA384
+		0x009f, // TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
+
+		// ChaCha20-Poly1305
+		0xcca9, // TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
+		0xcca8, // TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
+		0xccaa, // TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256
+
+		// AES-CCM (256-bit)
+		0xc0af, // TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8
+		0xc0ad, // TLS_ECDHE_ECDSA_WITH_AES_256_CCM
+		0xc0a3, // TLS_DHE_RSA_WITH_AES_256_CCM_8
+		0xc09f, // TLS_DHE_RSA_WITH_AES_256_CCM
+
+		// ARIA (256-bit)
+		0xc05d, // TLS_ECDHE_ECDSA_WITH_ARIA_256_GCM_SHA384
+		0xc061, // TLS_ECDHE_RSA_WITH_ARIA_256_GCM_SHA384
+		0xc057, // TLS_DHE_DSS_WITH_ARIA_256_GCM_SHA384
+		0xc053, // TLS_DHE_RSA_WITH_ARIA_256_GCM_SHA384
+
+		// DHE-DSS + AES-GCM (128-bit)
+		0x00a2, // TLS_DHE_DSS_WITH_AES_128_GCM_SHA256
+
+		// AES-CCM (128-bit)
+		0xc0ae, // TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8
+		0xc0ac, // TLS_ECDHE_ECDSA_WITH_AES_128_CCM
+		0xc0a2, // TLS_DHE_RSA_WITH_AES_128_CCM_8
+		0xc09e, // TLS_DHE_RSA_WITH_AES_128_CCM
+
+		// ARIA (128-bit)
+		0xc05c, // TLS_ECDHE_ECDSA_WITH_ARIA_128_GCM_SHA256
+		0xc060, // TLS_ECDHE_RSA_WITH_ARIA_128_GCM_SHA256
+		0xc056, // TLS_DHE_DSS_WITH_ARIA_128_GCM_SHA256
+		0xc052, // TLS_DHE_RSA_WITH_ARIA_128_GCM_SHA256
+
+		// ECDHE/DHE + AES-CBC-SHA384/256 (more)
+		0xc024, // TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
+		0x006a, // TLS_DHE_DSS_WITH_AES_256_CBC_SHA256
+		0xc023, // TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
+		0x0040, // TLS_DHE_DSS_WITH_AES_128_CBC_SHA256
+
+		// ECDHE/DHE + AES-CBC-SHA (legacy)
+		0xc00a, // TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
+		0xc014, // TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
+		0x0039, // TLS_DHE_RSA_WITH_AES_256_CBC_SHA
+		0x0038, // TLS_DHE_DSS_WITH_AES_256_CBC_SHA
+		0xc009, // TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
+		0xc013, // TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
+		0x0033, // TLS_DHE_RSA_WITH_AES_128_CBC_SHA
+		0x0032, // TLS_DHE_DSS_WITH_AES_128_CBC_SHA
+
+		// RSA + AES-GCM/CCM/ARIA (non-PFS, 256-bit)
+		0x009d, // TLS_RSA_WITH_AES_256_GCM_SHA384
+		0xc0a1, // TLS_RSA_WITH_AES_256_CCM_8
+		0xc09d, // TLS_RSA_WITH_AES_256_CCM
+		0xc051, // TLS_RSA_WITH_ARIA_256_GCM_SHA384
+
+		// RSA + AES-GCM/CCM/ARIA (non-PFS, 128-bit)
+		0x009c, // TLS_RSA_WITH_AES_128_GCM_SHA256
+		0xc0a0, // TLS_RSA_WITH_AES_128_CCM_8
+		0xc09c, // TLS_RSA_WITH_AES_128_CCM
+		0xc050, // TLS_RSA_WITH_ARIA_128_GCM_SHA256
+
+		// RSA + AES-CBC (non-PFS, legacy)
+		0x003d, // TLS_RSA_WITH_AES_256_CBC_SHA256
+		0x003c, // TLS_RSA_WITH_AES_128_CBC_SHA256
+		0x0035, // TLS_RSA_WITH_AES_256_CBC_SHA
+		0x002f, // TLS_RSA_WITH_AES_128_CBC_SHA
+
+		// Renegotiation indication
+		0x00ff, // TLS_EMPTY_RENEGOTIATION_INFO_SCSV
+	}
+
+	// defaultCurves contains the 10 supported groups from Claude CLI (including FFDHE)
+	defaultCurves = []utls.CurveID{
+		utls.X25519,          // 0x001d
+		utls.CurveP256,       // 0x0017 (secp256r1)
+		utls.CurveID(0x001e), // x448
+		utls.CurveP521,       // 0x0019 (secp521r1)
+		utls.CurveP384,       // 0x0018 (secp384r1)
+		utls.CurveID(0x0100), // ffdhe2048
+		utls.CurveID(0x0101), // ffdhe3072
+		utls.CurveID(0x0102), // ffdhe4096
+		utls.CurveID(0x0103), // ffdhe6144
+		utls.CurveID(0x0104), // ffdhe8192
+	}
+
+	// defaultPointFormats contains all 3 point formats from Claude CLI
+	defaultPointFormats = []uint8{
+		0, // uncompressed
+		1, // ansiX962_compressed_prime
+		2, // ansiX962_compressed_char2
+	}
+
+	// defaultSignatureAlgorithms contains the 20 signature algorithms from Claude CLI
+	defaultSignatureAlgorithms = []utls.SignatureScheme{
+		0x0403, // ecdsa_secp256r1_sha256
+		0x0503, // ecdsa_secp384r1_sha384
+		0x0603, // ecdsa_secp521r1_sha512
+		0x0807, // ed25519
+		0x0808, // ed448
+		0x0809, // rsa_pss_pss_sha256
+		0x080a, // rsa_pss_pss_sha384
+		0x080b, // rsa_pss_pss_sha512
+		0x0804, // rsa_pss_rsae_sha256
+		0x0805, // rsa_pss_rsae_sha384
+		0x0806, // rsa_pss_rsae_sha512
+		0x0401, // rsa_pkcs1_sha256
+		0x0501, // rsa_pkcs1_sha384
+		0x0601, // rsa_pkcs1_sha512
+		0x0303, // ecdsa_sha224
+		0x0301, // rsa_pkcs1_sha224
+		0x0302, // dsa_sha224
+		0x0402, // dsa_sha256
+		0x0502, // dsa_sha384
+		0x0602, // dsa_sha512
+	}
+)
+
+// NewDialer creates a new TLS fingerprint dialer.
+// baseDialer is used for TCP connection establishment (supports proxy scenarios).
+// If baseDialer is nil, direct TCP dial is used.
+func NewDialer(profile *Profile, baseDialer func(ctx context.Context, network, addr string) (net.Conn, error)) *Dialer {
+	if baseDialer == nil {
+		baseDialer = (&net.Dialer{}).DialContext
+	}
+	return &Dialer{profile: profile, baseDialer: baseDialer}
+}
+
+// NewHTTPProxyDialer creates a new TLS fingerprint dialer that works through HTTP/HTTPS proxies.
+// It establishes a CONNECT tunnel before performing TLS handshake with custom fingerprint.
+func NewHTTPProxyDialer(profile *Profile, proxyURL *url.URL) *HTTPProxyDialer {
+	return &HTTPProxyDialer{profile: profile, proxyURL: proxyURL}
+}
+
+// NewSOCKS5ProxyDialer creates a new TLS fingerprint dialer that works through SOCKS5 proxies.
+// It establishes a SOCKS5 tunnel before performing TLS handshake with custom fingerprint.
+func NewSOCKS5ProxyDialer(profile *Profile, proxyURL *url.URL) *SOCKS5ProxyDialer {
+	return &SOCKS5ProxyDialer{profile: profile, proxyURL: proxyURL}
+}
+
+// DialTLSContext establishes a TLS connection through SOCKS5 proxy with the configured fingerprint.
+// Flow: SOCKS5 CONNECT to target -> TLS handshake with utls on the tunnel
+func (d *SOCKS5ProxyDialer) DialTLSContext(ctx context.Context, network, addr string) (net.Conn, error) {
+	debugLog("[TLS Fingerprint SOCKS5] Connecting through proxy %s for target %s", d.proxyURL.Host, addr)
+
+	// Step 1: Create SOCKS5 dialer
+	var auth *proxy.Auth
+	if d.proxyURL.User != nil {
+		username := d.proxyURL.User.Username()
+		password, _ := d.proxyURL.User.Password()
+		auth = &proxy.Auth{
+			User:     username,
+			Password: password,
+		}
+	}
+
+	// Determine proxy address
+	proxyAddr := d.proxyURL.Host
+	if d.proxyURL.Port() == "" {
+		proxyAddr = net.JoinHostPort(d.proxyURL.Hostname(), "1080") // Default SOCKS5 port
+	}
+
+	socksDialer, err := proxy.SOCKS5("tcp", proxyAddr, auth, proxy.Direct)
+	if err != nil {
+		debugLog("[TLS Fingerprint SOCKS5] Failed to create SOCKS5 dialer: %v", err)
+		return nil, fmt.Errorf("create SOCKS5 dialer: %w", err)
+	}
+
+	// Step 2: Establish SOCKS5 tunnel to target
+	debugLog("[TLS Fingerprint SOCKS5] Establishing SOCKS5 tunnel to %s", addr)
+	conn, err := socksDialer.Dial("tcp", addr)
+	if err != nil {
+		debugLog("[TLS Fingerprint SOCKS5] Failed to connect through SOCKS5: %v", err)
+		return nil, fmt.Errorf("SOCKS5 connect: %w", err)
+	}
+	debugLog("[TLS Fingerprint SOCKS5] SOCKS5 tunnel established")
+
+	// Step 3: Perform TLS handshake on the tunnel with utls fingerprint
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		host = addr
+	}
+	debugLog("[TLS Fingerprint SOCKS5] Starting TLS handshake to %s", host)
+
+	// Build ClientHello specification from profile (Node.js/Claude CLI fingerprint)
+	spec := buildClientHelloSpecFromProfile(d.profile)
+	debugLog("[TLS Fingerprint SOCKS5] ClientHello spec: CipherSuites=%d, Extensions=%d, CompressionMethods=%v, TLSVersMax=0x%04x, TLSVersMin=0x%04x",
+		len(spec.CipherSuites), len(spec.Extensions), spec.CompressionMethods, spec.TLSVersMax, spec.TLSVersMin)
+
+	if d.profile != nil {
+		debugLog("[TLS Fingerprint SOCKS5] Using profile: %s, GREASE: %v", d.profile.Name, d.profile.EnableGREASE)
+	}
+
+	// Create uTLS connection on the tunnel
+	tlsConn := utls.UClient(conn, &utls.Config{
+		ServerName: host,
+	}, utls.HelloCustom)
+
+	if err := tlsConn.ApplyPreset(spec); err != nil {
+		debugLog("[TLS Fingerprint SOCKS5] ApplyPreset failed: %v", err)
+		_ = conn.Close()
+		return nil, fmt.Errorf("apply TLS preset: %w", err)
+	}
+
+	if err := tlsConn.Handshake(); err != nil {
+		debugLog("[TLS Fingerprint SOCKS5] Handshake FAILED: %v", err)
+		_ = conn.Close()
+		return nil, fmt.Errorf("TLS handshake failed: %w", err)
+	}
+
+	state := tlsConn.ConnectionState()
+	debugLog("[TLS Fingerprint SOCKS5] Handshake SUCCESS - Version: 0x%04x, CipherSuite: 0x%04x, ALPN: %s",
+		state.Version, state.CipherSuite, state.NegotiatedProtocol)
+
+	return tlsConn, nil
+}
+
+// DialTLSContext establishes a TLS connection through HTTP proxy with the configured fingerprint.
+// Flow: TCP connect to proxy -> CONNECT tunnel -> TLS handshake with utls
+func (d *HTTPProxyDialer) DialTLSContext(ctx context.Context, network, addr string) (net.Conn, error) {
+	debugLog("[TLS Fingerprint HTTPProxy] Connecting to proxy %s for target %s", d.proxyURL.Host, addr)
+
+	// Step 1: TCP connect to proxy server
+	var proxyAddr string
+	if d.proxyURL.Port() != "" {
+		proxyAddr = d.proxyURL.Host
+	} else {
+		// Default ports
+		if d.proxyURL.Scheme == "https" {
+			proxyAddr = net.JoinHostPort(d.proxyURL.Hostname(), "443")
+		} else {
+			proxyAddr = net.JoinHostPort(d.proxyURL.Hostname(), "80")
+		}
+	}
+
+	dialer := &net.Dialer{}
+	conn, err := dialer.DialContext(ctx, "tcp", proxyAddr)
+	if err != nil {
+		debugLog("[TLS Fingerprint HTTPProxy] Failed to connect to proxy: %v", err)
+		return nil, fmt.Errorf("connect to proxy: %w", err)
+	}
+	debugLog("[TLS Fingerprint HTTPProxy] Connected to proxy %s", proxyAddr)
+
+	// Step 2: Send CONNECT request to establish tunnel
+	req := &http.Request{
+		Method: "CONNECT",
+		URL:    &url.URL{Opaque: addr},
+		Host:   addr,
+		Header: make(http.Header),
+	}
+
+	// Add proxy authentication if present
+	if d.proxyURL.User != nil {
+		username := d.proxyURL.User.Username()
+		password, _ := d.proxyURL.User.Password()
+		auth := base64.StdEncoding.EncodeToString([]byte(username + ":" + password))
+		req.Header.Set("Proxy-Authorization", "Basic "+auth)
+	}
+
+	debugLog("[TLS Fingerprint HTTPProxy] Sending CONNECT request for %s", addr)
+	if err := req.Write(conn); err != nil {
+		_ = conn.Close()
+		debugLog("[TLS Fingerprint HTTPProxy] Failed to write CONNECT request: %v", err)
+		return nil, fmt.Errorf("write CONNECT request: %w", err)
+	}
+
+	// Step 3: Read CONNECT response
+	br := bufio.NewReader(conn)
+	resp, err := http.ReadResponse(br, req)
+	if err != nil {
+		_ = conn.Close()
+		debugLog("[TLS Fingerprint HTTPProxy] Failed to read CONNECT response: %v", err)
+		return nil, fmt.Errorf("read CONNECT response: %w", err)
+	}
+	defer func() { _ = resp.Body.Close() }()
+
+	if resp.StatusCode != http.StatusOK {
+		_ = conn.Close()
+		debugLog("[TLS Fingerprint HTTPProxy] CONNECT failed with status: %d %s", resp.StatusCode, resp.Status)
+		return nil, fmt.Errorf("proxy CONNECT failed: %s", resp.Status)
+	}
+	debugLog("[TLS Fingerprint HTTPProxy] CONNECT tunnel established")
+
+	// Step 4: Perform TLS handshake on the tunnel with utls fingerprint
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		host = addr
+	}
+	debugLog("[TLS Fingerprint HTTPProxy] Starting TLS handshake to %s", host)
+
+	// Build ClientHello specification (reuse the shared method)
+	spec := buildClientHelloSpecFromProfile(d.profile)
+	debugLog("[TLS Fingerprint HTTPProxy] ClientHello spec built with %d cipher suites, %d extensions",
+		len(spec.CipherSuites), len(spec.Extensions))
+
+	if d.profile != nil {
+		debugLog("[TLS Fingerprint HTTPProxy] Using profile: %s, GREASE: %v", d.profile.Name, d.profile.EnableGREASE)
+	}
+
+	// Create uTLS connection on the tunnel
+	// Note: TLS 1.3 cipher suites are handled automatically by utls when TLS 1.3 is in SupportedVersions
+	tlsConn := utls.UClient(conn, &utls.Config{
+		ServerName: host,
+	}, utls.HelloCustom)
+
+	if err := tlsConn.ApplyPreset(spec); err != nil {
+		debugLog("[TLS Fingerprint HTTPProxy] ApplyPreset failed: %v", err)
+		_ = conn.Close()
+		return nil, fmt.Errorf("apply TLS preset: %w", err)
+	}
+
+	if err := tlsConn.HandshakeContext(ctx); err != nil {
+		debugLog("[TLS Fingerprint HTTPProxy] Handshake FAILED: %v", err)
+		_ = conn.Close()
+		return nil, fmt.Errorf("TLS handshake failed: %w", err)
+	}
+
+	state := tlsConn.ConnectionState()
+	debugLog("[TLS Fingerprint HTTPProxy] Handshake SUCCESS - Version: 0x%04x, CipherSuite: 0x%04x, ALPN: %s",
+		state.Version, state.CipherSuite, state.NegotiatedProtocol)
+
+	return tlsConn, nil
+}
+
+// DialTLSContext establishes a TLS connection with the configured fingerprint.
+// This method is designed to be used as http.Transport.DialTLSContext.
+func (d *Dialer) DialTLSContext(ctx context.Context, network, addr string) (net.Conn, error) {
+	// Establish TCP connection using base dialer (supports proxy)
+	debugLog("[TLS Fingerprint] Dialing TCP to %s", addr)
+	conn, err := d.baseDialer(ctx, network, addr)
+	if err != nil {
+		debugLog("[TLS Fingerprint] TCP dial failed: %v", err)
+		return nil, err
+	}
+	debugLog("[TLS Fingerprint] TCP connected to %s", addr)
+
+	// Extract hostname for SNI
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		host = addr
+	}
+	debugLog("[TLS Fingerprint] SNI hostname: %s", host)
+
+	// Build ClientHello specification
+	spec := d.buildClientHelloSpec()
+	debugLog("[TLS Fingerprint] ClientHello spec built with %d cipher suites, %d extensions",
+		len(spec.CipherSuites), len(spec.Extensions))
+
+	// Log profile info
+	if d.profile != nil {
+		debugLog("[TLS Fingerprint] Using profile: %s, GREASE: %v", d.profile.Name, d.profile.EnableGREASE)
+	} else {
+		debugLog("[TLS Fingerprint] Using default profile (no custom config)")
+	}
+
+	// Create uTLS connection
+	// Note: TLS 1.3 cipher suites are handled automatically by utls when TLS 1.3 is in SupportedVersions
+	tlsConn := utls.UClient(conn, &utls.Config{
+		ServerName: host,
+	}, utls.HelloCustom)
+
+	// Apply fingerprint
+	if err := tlsConn.ApplyPreset(spec); err != nil {
+		debugLog("[TLS Fingerprint] ApplyPreset failed: %v", err)
+		_ = conn.Close()
+		return nil, err
+	}
+	debugLog("[TLS Fingerprint] Preset applied, starting handshake...")
+
+	// Perform TLS handshake
+	if err := tlsConn.HandshakeContext(ctx); err != nil {
+		debugLog("[TLS Fingerprint] Handshake FAILED: %v", err)
+		// Log more details about the connection state
+		debugLog("[TLS Fingerprint] Connection state - Local: %v, Remote: %v",
+			conn.LocalAddr(), conn.RemoteAddr())
+		_ = conn.Close()
+		return nil, fmt.Errorf("TLS handshake failed: %w", err)
+	}
+
+	// Log successful handshake details
+	state := tlsConn.ConnectionState()
+	debugLog("[TLS Fingerprint] Handshake SUCCESS - Version: 0x%04x, CipherSuite: 0x%04x, ALPN: %s",
+		state.Version, state.CipherSuite, state.NegotiatedProtocol)
+
+	return tlsConn, nil
+}
+
+// buildClientHelloSpec constructs the ClientHello specification based on the profile.
+func (d *Dialer) buildClientHelloSpec() *utls.ClientHelloSpec {
+	return buildClientHelloSpecFromProfile(d.profile)
+}
+
+// toUTLSCurves converts uint16 slice to utls.CurveID slice.
+func toUTLSCurves(curves []uint16) []utls.CurveID {
+	result := make([]utls.CurveID, len(curves))
+	for i, c := range curves {
+		result[i] = utls.CurveID(c)
+	}
+	return result
+}
+
+// buildClientHelloSpecFromProfile constructs ClientHelloSpec from a Profile.
+// This is a standalone function that can be used by both Dialer and HTTPProxyDialer.
+func buildClientHelloSpecFromProfile(profile *Profile) *utls.ClientHelloSpec {
+	// Get cipher suites
+	var cipherSuites []uint16
+	if profile != nil && len(profile.CipherSuites) > 0 {
+		cipherSuites = profile.CipherSuites
+	} else {
+		cipherSuites = defaultCipherSuites
+	}
+
+	// Get curves
+	var curves []utls.CurveID
+	if profile != nil && len(profile.Curves) > 0 {
+		curves = toUTLSCurves(profile.Curves)
+	} else {
+		curves = defaultCurves
+	}
+
+	// Get point formats
+	var pointFormats []uint8
+	if profile != nil && len(profile.PointFormats) > 0 {
+		pointFormats = profile.PointFormats
+	} else {
+		pointFormats = defaultPointFormats
+	}
+
+	// Check if GREASE is enabled
+	enableGREASE := profile != nil && profile.EnableGREASE
+
+	extensions := make([]utls.TLSExtension, 0, 16)
+
+	if enableGREASE {
+		extensions = append(extensions, &utls.UtlsGREASEExtension{})
+	}
+
+	// SNI extension - MUST be explicitly added for HelloCustom mode
+	// utls will populate the server name from Config.ServerName
+	extensions = append(extensions, &utls.SNIExtension{})
+
+	// Claude CLI extension order (captured from tshark):
+	// server_name(0), ec_point_formats(11), supported_groups(10), session_ticket(35),
+	// alpn(16), encrypt_then_mac(22), extended_master_secret(23),
+	// signature_algorithms(13), supported_versions(43),
+	// psk_key_exchange_modes(45), key_share(51)
+	extensions = append(extensions,
+		&utls.SupportedPointsExtension{SupportedPoints: pointFormats},
+		&utls.SupportedCurvesExtension{Curves: curves},
+		&utls.SessionTicketExtension{},
+		&utls.ALPNExtension{AlpnProtocols: []string{"http/1.1"}},
+		&utls.GenericExtension{Id: 22},
+		&utls.ExtendedMasterSecretExtension{},
+		&utls.SignatureAlgorithmsExtension{SupportedSignatureAlgorithms: defaultSignatureAlgorithms},
+		&utls.SupportedVersionsExtension{Versions: []uint16{
+			utls.VersionTLS13,
+			utls.VersionTLS12,
+		}},
+		&utls.PSKKeyExchangeModesExtension{Modes: []uint8{utls.PskModeDHE}},
+		&utls.KeyShareExtension{KeyShares: []utls.KeyShare{
+			{Group: utls.X25519},
+		}},
+	)
+
+	if enableGREASE {
+		extensions = append(extensions, &utls.UtlsGREASEExtension{})
+	}
+
+	return &utls.ClientHelloSpec{
+		CipherSuites:       cipherSuites,
+		CompressionMethods: []uint8{0}, // null compression only (standard)
+		Extensions:         extensions,
+		TLSVersMax:         utls.VersionTLS13,
+		TLSVersMin:         utls.VersionTLS10,
+	}
+}

backend/internal/pkg/tlsfingerprint/dialer_test.go

+// Package tlsfingerprint provides TLS fingerprint simulation for HTTP clients.
+//
+// Integration tests for verifying TLS fingerprint correctness.
+// These tests make actual network requests and should be run manually.
+//
+// Run with: go test -v ./internal/pkg/tlsfingerprint/...
+// Run integration tests: go test -v -run TestJA3 ./internal/pkg/tlsfingerprint/...
+package tlsfingerprint
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"testing"
+	"time"
+)
+
+// FingerprintResponse represents the response from tls.peet.ws/api/all.
+type FingerprintResponse struct {
+	IP    string  `json:"ip"`
+	TLS   TLSInfo `json:"tls"`
+	HTTP2 any     `json:"http2"`
+}
+
+// TLSInfo contains TLS fingerprint details.
+type TLSInfo struct {
+	JA3           string `json:"ja3"`
+	JA3Hash       string `json:"ja3_hash"`
+	JA4           string `json:"ja4"`
+	PeetPrint     string `json:"peetprint"`
+	PeetPrintHash string `json:"peetprint_hash"`
+	ClientRandom  string `json:"client_random"`
+	SessionID     string `json:"session_id"`
+}
+
+// TestDialerBasicConnection tests that the dialer can establish TLS connections.
+func TestDialerBasicConnection(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping network test in short mode")
+	}
+
+	// Create a dialer with default profile
+	profile := &Profile{
+		Name:         "Test Profile",
+		EnableGREASE: false,
+	}
+	dialer := NewDialer(profile, nil)
+
+	// Create HTTP client with custom TLS dialer
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialTLSContext: dialer.DialTLSContext,
+		},
+		Timeout: 30 * time.Second,
+	}
+
+	// Make a request to a known HTTPS endpoint
+	resp, err := client.Get("https://www.google.com")
+	if err != nil {
+		t.Fatalf("failed to connect: %v", err)
+	}
+	defer func() { _ = resp.Body.Close() }()
+
+	if resp.StatusCode != http.StatusOK {
+		t.Errorf("expected status 200, got %d", resp.StatusCode)
+	}
+}
+
+// TestJA3Fingerprint verifies the JA3/JA4 fingerprint matches expected value.
+// This test uses tls.peet.ws to verify the fingerprint.
+// Expected JA3 hash: 1a28e69016765d92e3b381168d68922c (Claude CLI / Node.js 20.x)
+// Expected JA4: t13d5911h1_a33745022dd6_1f22a2ca17c4 (d=domain) or t13i5911h1_... (i=IP)
+func TestJA3Fingerprint(t *testing.T) {
+	// Skip if network is unavailable or if running in short mode
+	if testing.Short() {
+		t.Skip("skipping integration test in short mode")
+	}
+
+	profile := &Profile{
+		Name:         "Claude CLI Test",
+		EnableGREASE: false,
+	}
+	dialer := NewDialer(profile, nil)
+
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialTLSContext: dialer.DialTLSContext,
+		},
+		Timeout: 30 * time.Second,
+	}
+
+	// Use tls.peet.ws fingerprint detection API
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	req, err := http.NewRequestWithContext(ctx, "GET", "https://tls.peet.ws/api/all", nil)
+	if err != nil {
+		t.Fatalf("failed to create request: %v", err)
+	}
+	req.Header.Set("User-Agent", "Claude Code/2.0.0 Node.js/20.0.0")
+
+	resp, err := client.Do(req)
+	if err != nil {
+		t.Fatalf("failed to get fingerprint: %v", err)
+	}
+	defer func() { _ = resp.Body.Close() }()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatalf("failed to read response: %v", err)
+	}
+
+	var fpResp FingerprintResponse
+	if err := json.Unmarshal(body, &fpResp); err != nil {
+		t.Logf("Response body: %s", string(body))
+		t.Fatalf("failed to parse fingerprint response: %v", err)
+	}
+
+	// Log all fingerprint information
+	t.Logf("JA3: %s", fpResp.TLS.JA3)
+	t.Logf("JA3 Hash: %s", fpResp.TLS.JA3Hash)
+	t.Logf("JA4: %s", fpResp.TLS.JA4)
+	t.Logf("PeetPrint: %s", fpResp.TLS.PeetPrint)
+	t.Logf("PeetPrint Hash: %s", fpResp.TLS.PeetPrintHash)
+
+	// Verify JA3 hash matches expected value
+	expectedJA3Hash := "1a28e69016765d92e3b381168d68922c"
+	if fpResp.TLS.JA3Hash == expectedJA3Hash {
+		t.Logf("✓ JA3 hash matches expected value: %s", expectedJA3Hash)
+	} else {
+		t.Errorf("✗ JA3 hash mismatch: got %s, expected %s", fpResp.TLS.JA3Hash, expectedJA3Hash)
+	}
+
+	// Verify JA4 fingerprint
+	// JA4 format: t[version][sni][cipher_count][ext_count][alpn]_[cipher_hash]_[ext_hash]
+	// Expected: t13d5910h1 (d=domain) or t13i5910h1 (i=IP)
+	// The suffix _a33745022dd6_1f22a2ca17c4 should match
+	expectedJA4Suffix := "_a33745022dd6_1f22a2ca17c4"
+	if strings.HasSuffix(fpResp.TLS.JA4, expectedJA4Suffix) {
+		t.Logf("✓ JA4 suffix matches expected value: %s", expectedJA4Suffix)
+	} else {
+		t.Errorf("✗ JA4 suffix mismatch: got %s, expected suffix %s", fpResp.TLS.JA4, expectedJA4Suffix)
+	}
+
+	// Verify JA4 prefix (t13d5911h1 or t13i5911h1)
+	// d = domain (SNI present), i = IP (no SNI)
+	// Since we connect to tls.peet.ws (domain), we expect 'd'
+	expectedJA4Prefix := "t13d5911h1"
+	if strings.HasPrefix(fpResp.TLS.JA4, expectedJA4Prefix) {
+		t.Logf("✓ JA4 prefix matches: %s (t13=TLS1.3, d=domain, 59=ciphers, 11=extensions, h1=HTTP/1.1)", expectedJA4Prefix)
+	} else {
+		// Also accept 'i' variant for IP connections
+		altPrefix := "t13i5911h1"
+		if strings.HasPrefix(fpResp.TLS.JA4, altPrefix) {
+			t.Logf("✓ JA4 prefix matches (IP variant): %s", altPrefix)
+		} else {
+			t.Errorf("✗ JA4 prefix mismatch: got %s, expected %s or %s", fpResp.TLS.JA4, expectedJA4Prefix, altPrefix)
+		}
+	}
+
+	// Verify JA3 contains expected cipher suites (TLS 1.3 ciphers at the beginning)
+	if strings.Contains(fpResp.TLS.JA3, "4866-4867-4865") {
+		t.Logf("✓ JA3 contains expected TLS 1.3 cipher suites")
+	} else {
+		t.Logf("Warning: JA3 does not contain expected TLS 1.3 cipher suites")
+	}
+
+	// Verify extension list (should be 11 extensions including SNI)
+	// Expected: 0-11-10-35-16-22-23-13-43-45-51
+	expectedExtensions := "0-11-10-35-16-22-23-13-43-45-51"
+	if strings.Contains(fpResp.TLS.JA3, expectedExtensions) {
+		t.Logf("✓ JA3 contains expected extension list: %s", expectedExtensions)
+	} else {
+		t.Logf("Warning: JA3 extension list may differ")
+	}
+}
+
+// TestDialerWithProfile tests that different profiles produce different fingerprints.
+func TestDialerWithProfile(t *testing.T) {
+	// Create two dialers with different profiles
+	profile1 := &Profile{
+		Name:         "Profile 1 - No GREASE",
+		EnableGREASE: false,
+	}
+	profile2 := &Profile{
+		Name:         "Profile 2 - With GREASE",
+		EnableGREASE: true,
+	}
+
+	dialer1 := NewDialer(profile1, nil)
+	dialer2 := NewDialer(profile2, nil)
+
+	// Build specs and compare
+	// Note: We can't directly compare JA3 without making network requests
+	// but we can verify the specs are different
+	spec1 := dialer1.buildClientHelloSpec()
+	spec2 := dialer2.buildClientHelloSpec()
+
+	// Profile with GREASE should have more extensions
+	if len(spec2.Extensions) <= len(spec1.Extensions) {
+		t.Error("expected GREASE profile to have more extensions")
+	}
+}
+
+// TestHTTPProxyDialerBasic tests HTTP proxy dialer creation.
+// Note: This is a unit test - actual proxy testing requires a proxy server.
+func TestHTTPProxyDialerBasic(t *testing.T) {
+	profile := &Profile{
+		Name:         "Test Profile",
+		EnableGREASE: false,
+	}
+
+	// Test that dialer is created without panic
+	proxyURL := mustParseURL("http://proxy.example.com:8080")
+	dialer := NewHTTPProxyDialer(profile, proxyURL)
+
+	if dialer == nil {
+		t.Fatal("expected dialer to be created")
+	}
+	if dialer.profile != profile {
+		t.Error("expected profile to be set")
+	}
+	if dialer.proxyURL != proxyURL {
+		t.Error("expected proxyURL to be set")
+	}
+}
+
+// TestSOCKS5ProxyDialerBasic tests SOCKS5 proxy dialer creation.
+// Note: This is a unit test - actual proxy testing requires a proxy server.
+func TestSOCKS5ProxyDialerBasic(t *testing.T) {
+	profile := &Profile{
+		Name:         "Test Profile",
+		EnableGREASE: false,
+	}
+
+	// Test that dialer is created without panic
+	proxyURL := mustParseURL("socks5://proxy.example.com:1080")
+	dialer := NewSOCKS5ProxyDialer(profile, proxyURL)
+
+	if dialer == nil {
+		t.Fatal("expected dialer to be created")
+	}
+	if dialer.profile != profile {
+		t.Error("expected profile to be set")
+	}
+	if dialer.proxyURL != proxyURL {
+		t.Error("expected proxyURL to be set")
+	}
+}
+
+// TestBuildClientHelloSpec tests ClientHello spec construction.
+func TestBuildClientHelloSpec(t *testing.T) {
+	// Test with nil profile (should use defaults)
+	spec := buildClientHelloSpecFromProfile(nil)
+
+	if len(spec.CipherSuites) == 0 {
+		t.Error("expected cipher suites to be set")
+	}
+	if len(spec.Extensions) == 0 {
+		t.Error("expected extensions to be set")
+	}
+
+	// Verify default cipher suites are used
+	if len(spec.CipherSuites) != len(defaultCipherSuites) {
+		t.Errorf("expected %d cipher suites, got %d", len(defaultCipherSuites), len(spec.CipherSuites))
+	}
+
+	// Test with custom profile
+	customProfile := &Profile{
+		Name:         "Custom",
+		EnableGREASE: false,
+		CipherSuites: []uint16{0x1301, 0x1302},
+	}
+	spec = buildClientHelloSpecFromProfile(customProfile)
+
+	if len(spec.CipherSuites) != 2 {
+		t.Errorf("expected 2 cipher suites, got %d", len(spec.CipherSuites))
+	}
+}
+
+// TestToUTLSCurves tests curve ID conversion.
+func TestToUTLSCurves(t *testing.T) {
+	input := []uint16{0x001d, 0x0017, 0x0018}
+	result := toUTLSCurves(input)
+
+	if len(result) != len(input) {
+		t.Errorf("expected %d curves, got %d", len(input), len(result))
+	}
+
+	for i, curve := range result {
+		if uint16(curve) != input[i] {
+			t.Errorf("curve %d: expected 0x%04x, got 0x%04x", i, input[i], uint16(curve))
+		}
+	}
+}
+
+// Helper function to parse URL without error handling.
+func mustParseURL(rawURL string) *url.URL {
+	u, err := url.Parse(rawURL)
+	if err != nil {
+		panic(err)
+	}
+	return u
+}

backend/internal/pkg/tlsfingerprint/registry.go

+// 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
+}

backend/internal/pkg/tlsfingerprint/registry_test.go

+package tlsfingerprint
+
+import (
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+)
+
+func TestNewRegistry(t *testing.T) {
+	r := NewRegistry()
+
+	// Should have exactly one profile (the default)
+	if r.ProfileCount() != 1 {
+		t.Errorf("expected 1 profile, got %d", r.ProfileCount())
+	}
+
+	// Should have the default profile
+	profile := r.GetDefaultProfile()
+	if profile == nil {
+		t.Error("expected default profile to exist")
+	}
+
+	// Default profile name should be in the list
+	names := r.ProfileNames()
+	if len(names) != 1 || names[0] != DefaultProfileName {
+		t.Errorf("expected profile names to be [%s], got %v", DefaultProfileName, names)
+	}
+}
+
+func TestRegisterProfile(t *testing.T) {
+	r := NewRegistry()
+
+	// Register a new profile
+	customProfile := &Profile{
+		Name:         "Custom Profile",
+		EnableGREASE: true,
+	}
+	r.RegisterProfile("custom", customProfile)
+
+	// Should now have 2 profiles
+	if r.ProfileCount() != 2 {
+		t.Errorf("expected 2 profiles, got %d", r.ProfileCount())
+	}
+
+	// Should be able to retrieve the custom profile
+	retrieved := r.GetProfile("custom")
+	if retrieved == nil {
+		t.Fatal("expected custom profile to exist")
+	}
+	if retrieved.Name != "Custom Profile" {
+		t.Errorf("expected profile name 'Custom Profile', got '%s'", retrieved.Name)
+	}
+	if !retrieved.EnableGREASE {
+		t.Error("expected EnableGREASE to be true")
+	}
+}
+
+func TestGetProfile(t *testing.T) {
+	r := NewRegistry()
+
+	// Get existing profile
+	profile := r.GetProfile(DefaultProfileName)
+	if profile == nil {
+		t.Error("expected default profile to exist")
+	}
+
+	// Get non-existing profile
+	nonExistent := r.GetProfile("nonexistent")
+	if nonExistent != nil {
+		t.Error("expected nil for non-existent profile")
+	}
+}
+
+func TestGetProfileByAccountID(t *testing.T) {
+	r := NewRegistry()
+
+	// With only default profile, all account IDs should return the same profile
+	for i := int64(0); i < 10; i++ {
+		profile := r.GetProfileByAccountID(i)
+		if profile == nil {
+			t.Errorf("expected profile for account %d, got nil", i)
+		}
+	}
+
+	// Add more profiles
+	r.RegisterProfile("profile_a", &Profile{Name: "Profile A"})
+	r.RegisterProfile("profile_b", &Profile{Name: "Profile B"})
+
+	// Now we have 3 profiles: claude_cli_v2, profile_a, profile_b
+	// Names are sorted, so order is: claude_cli_v2, profile_a, profile_b
+	expectedOrder := []string{DefaultProfileName, "profile_a", "profile_b"}
+	names := r.ProfileNames()
+	for i, name := range expectedOrder {
+		if names[i] != name {
+			t.Errorf("expected name at index %d to be %s, got %s", i, name, names[i])
+		}
+	}
+
+	// Test modulo selection
+	// Account ID 0 % 3 = 0 -> claude_cli_v2
+	// Account ID 1 % 3 = 1 -> profile_a
+	// Account ID 2 % 3 = 2 -> profile_b
+	// Account ID 3 % 3 = 0 -> claude_cli_v2
+	testCases := []struct {
+		accountID    int64
+		expectedName string
+	}{
+		{0, "Claude CLI 2.x (Node.js 20.x + OpenSSL 3.x)"},
+		{1, "Profile A"},
+		{2, "Profile B"},
+		{3, "Claude CLI 2.x (Node.js 20.x + OpenSSL 3.x)"},
+		{4, "Profile A"},
+		{5, "Profile B"},
+		{100, "Profile A"}, // 100 % 3 = 1
+		{-1, "Profile A"},  // |-1| % 3 = 1
+		{-3, "Claude CLI 2.x (Node.js 20.x + OpenSSL 3.x)"}, // |-3| % 3 = 0
+	}
+
+	for _, tc := range testCases {
+		profile := r.GetProfileByAccountID(tc.accountID)
+		if profile == nil {
+			t.Errorf("expected profile for account %d, got nil", tc.accountID)
+			continue
+		}
+		if profile.Name != tc.expectedName {
+			t.Errorf("account %d: expected profile name '%s', got '%s'", tc.accountID, tc.expectedName, profile.Name)
+		}
+	}
+}
+
+func TestNewRegistryFromConfig(t *testing.T) {
+	// Test with nil config
+	r := NewRegistryFromConfig(nil)
+	if r.ProfileCount() != 1 {
+		t.Errorf("expected 1 profile with nil config, got %d", r.ProfileCount())
+	}
+
+	// Test with disabled config
+	disabledCfg := &config.TLSFingerprintConfig{
+		Enabled: false,
+	}
+	r = NewRegistryFromConfig(disabledCfg)
+	if r.ProfileCount() != 1 {
+		t.Errorf("expected 1 profile with disabled config, got %d", r.ProfileCount())
+	}
+
+	// Test with enabled config and custom profiles
+	enabledCfg := &config.TLSFingerprintConfig{
+		Enabled: true,
+		Profiles: map[string]config.TLSProfileConfig{
+			"custom1": {
+				Name:         "Custom Profile 1",
+				EnableGREASE: true,
+			},
+			"custom2": {
+				Name:         "Custom Profile 2",
+				EnableGREASE: false,
+			},
+		},
+	}
+	r = NewRegistryFromConfig(enabledCfg)
+
+	// Should have 3 profiles: default + 2 custom
+	if r.ProfileCount() != 3 {
+		t.Errorf("expected 3 profiles, got %d", r.ProfileCount())
+	}
+
+	// Check custom profiles exist
+	custom1 := r.GetProfile("custom1")
+	if custom1 == nil || custom1.Name != "Custom Profile 1" {
+		t.Error("expected custom1 profile to exist with correct name")
+	}
+	custom2 := r.GetProfile("custom2")
+	if custom2 == nil || custom2.Name != "Custom Profile 2" {
+		t.Error("expected custom2 profile to exist with correct name")
+	}
+}
+
+func TestProfileNames(t *testing.T) {
+	r := NewRegistry()
+
+	// Add profiles in non-alphabetical order
+	r.RegisterProfile("zebra", &Profile{Name: "Zebra"})
+	r.RegisterProfile("alpha", &Profile{Name: "Alpha"})
+	r.RegisterProfile("beta", &Profile{Name: "Beta"})
+
+	names := r.ProfileNames()
+
+	// Should be sorted alphabetically
+	expected := []string{"alpha", "beta", DefaultProfileName, "zebra"}
+	if len(names) != len(expected) {
+		t.Errorf("expected %d names, got %d", len(expected), len(names))
+	}
+	for i, name := range expected {
+		if names[i] != name {
+			t.Errorf("expected name at index %d to be %s, got %s", i, name, names[i])
+		}
+	}
+
+	// Test that returned slice is a copy (modifying it shouldn't affect registry)
+	names[0] = "modified"
+	originalNames := r.ProfileNames()
+	if originalNames[0] == "modified" {
+		t.Error("modifying returned slice should not affect registry")
+	}
+}
+
+func TestConcurrentAccess(t *testing.T) {
+	r := NewRegistry()
+
+	// Run concurrent reads and writes
+	done := make(chan bool)
+
+	// Writers
+	for i := 0; i < 10; i++ {
+		go func(id int) {
+			for j := 0; j < 100; j++ {
+				r.RegisterProfile("concurrent"+string(rune('0'+id)), &Profile{Name: "Concurrent"})
+			}
+			done <- true
+		}(i)
+	}
+
+	// Readers
+	for i := 0; i < 10; i++ {
+		go func(id int) {
+			for j := 0; j < 100; j++ {
+				_ = r.ProfileCount()
+				_ = r.ProfileNames()
+				_ = r.GetProfileByAccountID(int64(id * j))
+				_ = r.GetProfile(DefaultProfileName)
+			}
+			done <- true
+		}(i)
+	}
+
+	// Wait for all goroutines
+	for i := 0; i < 20; i++ {
+		<-done
+	}
+
+	// Test should pass without data races (run with -race flag)
+}

backend/internal/repository/http_upstream.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"log"
 	"net"
 	"net/http"
 	"net/url"
@@ -14,10 +15,19 @@ import (
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/proxyutil"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/tlsfingerprint"
 	"github.com/Wei-Shaw/sub2api/internal/service"
 	"github.com/Wei-Shaw/sub2api/internal/util/urlvalidator"
+	"github.com/gin-gonic/gin"
 )
 
+// debugLog prints log only in non-release mode.
+func debugLog(format string, v ...any) {
+	if gin.Mode() != gin.ReleaseMode {
+		log.Printf(format, v...)
+	}
+}
+
 // 默认配置常量
 // 这些值在配置文件未指定时作为回退默认值使用
 const (
@@ -150,6 +160,170 @@ func (s *httpUpstreamService) Do(req *http.Request, proxyURL string, accountID i
 	return resp, nil
 }
 
+// DoWithTLS 执行带 TLS 指纹伪装的 HTTP 请求
+// 根据 enableTLSFingerprint 参数决定是否使用 TLS 指纹
+//
+// 参数:
+//   - req: HTTP 请求对象
+//   - proxyURL: 代理地址，空字符串表示直连
+//   - accountID: 账户 ID，用于账户级隔离和 TLS 指纹模板选择
+//   - accountConcurrency: 账户并发限制，用于动态调整连接池大小
+//   - enableTLSFingerprint: 是否启用 TLS 指纹伪装
+//
+// TLS 指纹说明:
+//   - 当 enableTLSFingerprint=true 时，使用 utls 库模拟 Claude CLI 的 TLS 指纹
+//   - 指纹模板根据 accountID % len(profiles) 自动选择
+//   - 支持直连、HTTP/HTTPS 代理、SOCKS5 代理三种场景
+func (s *httpUpstreamService) DoWithTLS(req *http.Request, proxyURL string, accountID int64, accountConcurrency int, enableTLSFingerprint bool) (*http.Response, error) {
+	// 如果未启用 TLS 指纹，直接使用标准请求路径
+	if !enableTLSFingerprint {
+		return s.Do(req, proxyURL, accountID, accountConcurrency)
+	}
+
+	// TLS 指纹已启用，记录调试日志
+	targetHost := ""
+	if req != nil && req.URL != nil {
+		targetHost = req.URL.Host
+	}
+	proxyInfo := "direct"
+	if proxyURL != "" {
+		proxyInfo = proxyURL
+	}
+	debugLog("[TLS Fingerprint] Account %d: TLS fingerprint ENABLED, target=%s, proxy=%s", accountID, targetHost, proxyInfo)
+
+	if err := s.validateRequestHost(req); err != nil {
+		return nil, err
+	}
+
+	// 获取 TLS 指纹 Profile
+	registry := tlsfingerprint.GlobalRegistry()
+	profile := registry.GetProfileByAccountID(accountID)
+	if profile == nil {
+		// 如果获取不到 profile，回退到普通请求
+		debugLog("[TLS Fingerprint] Account %d: WARNING - no profile found, falling back to standard request", accountID)
+		return s.Do(req, proxyURL, accountID, accountConcurrency)
+	}
+
+	debugLog("[TLS Fingerprint] Account %d: Using profile '%s' (GREASE=%v)", accountID, profile.Name, profile.EnableGREASE)
+
+	// 获取或创建带 TLS 指纹的客户端
+	entry, err := s.acquireClientWithTLS(proxyURL, accountID, accountConcurrency, profile)
+	if err != nil {
+		debugLog("[TLS Fingerprint] Account %d: Failed to acquire TLS client: %v", accountID, err)
+		return nil, err
+	}
+
+	// 执行请求
+	resp, err := entry.client.Do(req)
+	if err != nil {
+		// 请求失败，立即减少计数
+		atomic.AddInt64(&entry.inFlight, -1)
+		atomic.StoreInt64(&entry.lastUsed, time.Now().UnixNano())
+		debugLog("[TLS Fingerprint] Account %d: Request FAILED: %v", accountID, err)
+		return nil, err
+	}
+
+	debugLog("[TLS Fingerprint] Account %d: Request SUCCESS, status=%d", accountID, resp.StatusCode)
+
+	// 包装响应体，在关闭时自动减少计数并更新时间戳
+	resp.Body = wrapTrackedBody(resp.Body, func() {
+		atomic.AddInt64(&entry.inFlight, -1)
+		atomic.StoreInt64(&entry.lastUsed, time.Now().UnixNano())
+	})
+
+	return resp, nil
+}
+
+// acquireClientWithTLS 获取或创建带 TLS 指纹的客户端
+func (s *httpUpstreamService) acquireClientWithTLS(proxyURL string, accountID int64, accountConcurrency int, profile *tlsfingerprint.Profile) (*upstreamClientEntry, error) {
+	return s.getClientEntryWithTLS(proxyURL, accountID, accountConcurrency, profile, true, true)
+}
+
+// getClientEntryWithTLS 获取或创建带 TLS 指纹的客户端条目
+// TLS 指纹客户端使用独立的缓存键，与普通客户端隔离
+func (s *httpUpstreamService) getClientEntryWithTLS(proxyURL string, accountID int64, accountConcurrency int, profile *tlsfingerprint.Profile, markInFlight bool, enforceLimit bool) (*upstreamClientEntry, error) {
+	isolation := s.getIsolationMode()
+	proxyKey, parsedProxy := normalizeProxyURL(proxyURL)
+	// TLS 指纹客户端使用独立的缓存键，加 "tls:" 前缀
+	cacheKey := "tls:" + buildCacheKey(isolation, proxyKey, accountID)
+	poolKey := s.buildPoolKey(isolation, accountConcurrency) + ":tls"
+
+	now := time.Now()
+	nowUnix := now.UnixNano()
+
+	// 读锁快速路径
+	s.mu.RLock()
+	if entry, ok := s.clients[cacheKey]; ok && s.shouldReuseEntry(entry, isolation, proxyKey, poolKey) {
+		atomic.StoreInt64(&entry.lastUsed, nowUnix)
+		if markInFlight {
+			atomic.AddInt64(&entry.inFlight, 1)
+		}
+		s.mu.RUnlock()
+		debugLog("[TLS Fingerprint] Account %d: Reusing existing TLS client (cacheKey=%s)", accountID, cacheKey)
+		return entry, nil
+	}
+	s.mu.RUnlock()
+
+	// 写锁慢路径
+	s.mu.Lock()
+	if entry, ok := s.clients[cacheKey]; ok {
+		if s.shouldReuseEntry(entry, isolation, proxyKey, poolKey) {
+			atomic.StoreInt64(&entry.lastUsed, nowUnix)
+			if markInFlight {
+				atomic.AddInt64(&entry.inFlight, 1)
+			}
+			s.mu.Unlock()
+			debugLog("[TLS Fingerprint] Account %d: Reusing existing TLS client (cacheKey=%s)", accountID, cacheKey)
+			return entry, nil
+		}
+		debugLog("[TLS Fingerprint] Account %d: Evicting stale TLS client (cacheKey=%s, proxyChanged=%v, poolChanged=%v)",
+			accountID, cacheKey, entry.proxyKey != proxyKey, entry.poolKey != poolKey)
+		s.removeClientLocked(cacheKey, entry)
+	}
+
+	// 超出缓存上限时尝试淘汰
+	if enforceLimit && s.maxUpstreamClients() > 0 {
+		s.evictIdleLocked(now)
+		if len(s.clients) >= s.maxUpstreamClients() {
+			if !s.evictOldestIdleLocked() {
+				s.mu.Unlock()
+				return nil, errUpstreamClientLimitReached
+			}
+		}
+	}
+
+	// 创建带 TLS 指纹的 Transport
+	debugLog("[TLS Fingerprint] Account %d: Creating NEW TLS fingerprint client (cacheKey=%s, proxy=%s)",
+		accountID, cacheKey, proxyKey)
+	settings := s.resolvePoolSettings(isolation, accountConcurrency)
+	transport, err := buildUpstreamTransportWithTLSFingerprint(settings, parsedProxy, profile)
+	if err != nil {
+		s.mu.Unlock()
+		return nil, fmt.Errorf("build TLS fingerprint transport: %w", err)
+	}
+
+	client := &http.Client{Transport: transport}
+	if s.shouldValidateResolvedIP() {
+		client.CheckRedirect = s.redirectChecker
+	}
+
+	entry := &upstreamClientEntry{
+		client:   client,
+		proxyKey: proxyKey,
+		poolKey:  poolKey,
+	}
+	atomic.StoreInt64(&entry.lastUsed, nowUnix)
+	if markInFlight {
+		atomic.StoreInt64(&entry.inFlight, 1)
+	}
+	s.clients[cacheKey] = entry
+
+	s.evictIdleLocked(now)
+	s.evictOverLimitLocked()
+	s.mu.Unlock()
+	return entry, nil
+}
+
 func (s *httpUpstreamService) shouldValidateResolvedIP() bool {
 	if s.cfg == nil {
 		return false
@@ -618,6 +792,64 @@ func buildUpstreamTransport(settings poolSettings, proxyURL *url.URL) (*http.Tra
 	return transport, nil
 }
 
+// buildUpstreamTransportWithTLSFingerprint 构建带 TLS 指纹伪装的 Transport
+// 使用 utls 库模拟 Claude CLI 的 TLS 指纹
+//
+// 参数:
+//   - settings: 连接池配置
+//   - proxyURL: 代理 URL（nil 表示直连）
+//   - profile: TLS 指纹配置
+//
+// 返回:
+//   - *http.Transport: 配置好的 Transport 实例
+//   - error: 配置错误
+//
+// 代理类型处理:
+//   - nil/空: 直连，使用 TLSFingerprintDialer
+//   - http/https: HTTP 代理，使用 HTTPProxyDialer（CONNECT 隧道 + utls 握手）
+//   - socks5: SOCKS5 代理，使用 SOCKS5ProxyDialer（SOCKS5 隧道 + utls 握手）
+func buildUpstreamTransportWithTLSFingerprint(settings poolSettings, proxyURL *url.URL, profile *tlsfingerprint.Profile) (*http.Transport, error) {
+	transport := &http.Transport{
+		MaxIdleConns:          settings.maxIdleConns,
+		MaxIdleConnsPerHost:   settings.maxIdleConnsPerHost,
+		MaxConnsPerHost:       settings.maxConnsPerHost,
+		IdleConnTimeout:       settings.idleConnTimeout,
+		ResponseHeaderTimeout: settings.responseHeaderTimeout,
+		// 禁用默认的 TLS，我们使用自定义的 DialTLSContext
+		ForceAttemptHTTP2: false,
+	}
+
+	// 根据代理类型选择合适的 TLS 指纹 Dialer
+	if proxyURL == nil {
+		// 直连：使用 TLSFingerprintDialer
+		debugLog("[TLS Fingerprint Transport] Using DIRECT TLS dialer (no proxy)")
+		dialer := tlsfingerprint.NewDialer(profile, nil)
+		transport.DialTLSContext = dialer.DialTLSContext
+	} else {
+		scheme := strings.ToLower(proxyURL.Scheme)
+		switch scheme {
+		case "socks5", "socks5h":
+			// SOCKS5 代理：使用 SOCKS5ProxyDialer
+			debugLog("[TLS Fingerprint Transport] Using SOCKS5 TLS dialer (proxy=%s)", proxyURL.Host)
+			socks5Dialer := tlsfingerprint.NewSOCKS5ProxyDialer(profile, proxyURL)
+			transport.DialTLSContext = socks5Dialer.DialTLSContext
+		case "http", "https":
+			// HTTP/HTTPS 代理：使用 HTTPProxyDialer（CONNECT 隧道）
+			debugLog("[TLS Fingerprint Transport] Using HTTP CONNECT TLS dialer (proxy=%s)", proxyURL.Host)
+			httpDialer := tlsfingerprint.NewHTTPProxyDialer(profile, proxyURL)
+			transport.DialTLSContext = httpDialer.DialTLSContext
+		default:
+			// 未知代理类型，回退到普通代理配置（无 TLS 指纹）
+			debugLog("[TLS Fingerprint Transport] WARNING: Unknown proxy scheme '%s', falling back to standard proxy (NO TLS fingerprint)", scheme)
+			if err := proxyutil.ConfigureTransportProxy(transport, proxyURL); err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	return transport, nil
+}
+
 // trackedBody 带跟踪功能的响应体包装器
 // 在 Close 时执行回调，用于更新请求计数
 type trackedBody struct {

backend/internal/service/account.go

@@ -576,6 +576,25 @@ func (a *Account) IsAnthropicOAuthOrSetupToken() bool {
 	return a.Platform == PlatformAnthropic && (a.Type == AccountTypeOAuth || a.Type == AccountTypeSetupToken)
 }
 
+// IsTLSFingerprintEnabled 检查是否启用 TLS 指纹伪装
+// 仅适用于 Anthropic OAuth/SetupToken 类型账号
+// 启用后将模拟 Claude Code (Node.js) 客户端的 TLS 握手特征
+func (a *Account) IsTLSFingerprintEnabled() bool {
+	// 仅支持 Anthropic OAuth/SetupToken 账号
+	if !a.IsAnthropicOAuthOrSetupToken() {
+		return false
+	}
+	if a.Extra == nil {
+		return false
+	}
+	if v, ok := a.Extra["enable_tls_fingerprint"]; ok {
+		if enabled, ok := v.(bool); ok {
+			return enabled
+		}
+	}
+	return false
+}
+
 // GetWindowCostLimit 获取 5h 窗口费用阈值（美元）
 // 返回 0 表示未启用
 func (a *Account) GetWindowCostLimit() float64 {

backend/internal/service/account_test_service.go

@@ -265,7 +265,7 @@ func (s *AccountTestService) testClaudeAccountConnection(c *gin.Context, account
 		proxyURL = account.Proxy.URL()
 	}
 
-	resp, err := s.httpUpstream.Do(req, proxyURL, account.ID, account.Concurrency)
+	resp, err := s.httpUpstream.DoWithTLS(req, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 	if err != nil {
 		return s.sendErrorAndEnd(c, fmt.Sprintf("Request failed: %s", err.Error()))
 	}
@@ -375,7 +375,7 @@ func (s *AccountTestService) testOpenAIAccountConnection(c *gin.Context, account
 		proxyURL = account.Proxy.URL()
 	}
 
-	resp, err := s.httpUpstream.Do(req, proxyURL, account.ID, account.Concurrency)
+	resp, err := s.httpUpstream.DoWithTLS(req, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 	if err != nil {
 		return s.sendErrorAndEnd(c, fmt.Sprintf("Request failed: %s", err.Error()))
 	}
@@ -446,7 +446,7 @@ func (s *AccountTestService) testGeminiAccountConnection(c *gin.Context, account
 		proxyURL = account.Proxy.URL()
 	}
 
-	resp, err := s.httpUpstream.Do(req, proxyURL, account.ID, account.Concurrency)
+	resp, err := s.httpUpstream.DoWithTLS(req, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 	if err != nil {
 		return s.sendErrorAndEnd(c, fmt.Sprintf("Request failed: %s", err.Error()))
 	}

backend/internal/service/gateway_service.go

@@ -44,6 +44,13 @@ func (s *GatewayService) debugModelRoutingEnabled() bool {
 	return v == "1" || v == "true" || v == "yes" || v == "on"
 }
 
+// debugLog prints log only in non-release mode.
+func debugLog(format string, v ...any) {
+	if gin.Mode() != gin.ReleaseMode {
+		log.Printf(format, v...)
+	}
+}
+
 func shortSessionHash(sessionHash string) string {
 	if sessionHash == "" {
 		return ""
@@ -412,6 +419,14 @@ func (s *GatewayService) SelectAccountForModelWithExclusions(ctx context.Context
 // SelectAccountWithLoadAwareness selects account with load-awareness and wait plan.
 // metadataUserID: 已废弃参数，会话限制现在统一使用 sessionHash
 func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}, metadataUserID string) (*AccountSelectionResult, error) {
+	// 调试日志：记录调度入口参数
+	excludedIDsList := make([]int64, 0, len(excludedIDs))
+	for id := range excludedIDs {
+		excludedIDsList = append(excludedIDsList, id)
+	}
+	debugLog("[AccountScheduling] Starting account selection: groupID=%v model=%s session=%s excludedIDs=%v",
+		derefGroupID(groupID), requestedModel, shortSessionHash(sessionHash), excludedIDsList)
+
 	cfg := s.schedulingConfig()
 
 	var stickyAccountID int64
@@ -1087,7 +1102,16 @@ func (s *GatewayService) resolvePlatform(ctx context.Context, groupID *int64, gr
 
 func (s *GatewayService) listSchedulableAccounts(ctx context.Context, groupID *int64, platform string, hasForcePlatform bool) ([]Account, bool, error) {
 	if s.schedulerSnapshot != nil {
-		return s.schedulerSnapshot.ListSchedulableAccounts(ctx, groupID, platform, hasForcePlatform)
+		accounts, useMixed, err := s.schedulerSnapshot.ListSchedulableAccounts(ctx, groupID, platform, hasForcePlatform)
+		if err == nil {
+			debugLog("[AccountScheduling] listSchedulableAccounts (snapshot): groupID=%v platform=%s useMixed=%v count=%d",
+				derefGroupID(groupID), platform, useMixed, len(accounts))
+			for _, acc := range accounts {
+				debugLog("[AccountScheduling]   - Account ID=%d Name=%s Platform=%s Type=%s Status=%s TLSFingerprint=%v",
+					acc.ID, acc.Name, acc.Platform, acc.Type, acc.Status, acc.IsTLSFingerprintEnabled())
+			}
+		}
+		return accounts, useMixed, err
 	}
 	useMixed := (platform == PlatformAnthropic || platform == PlatformGemini) && !hasForcePlatform
 	if useMixed {
@@ -1100,6 +1124,7 @@ func (s *GatewayService) listSchedulableAccounts(ctx context.Context, groupID *i
 			accounts, err = s.accountRepo.ListSchedulableByPlatforms(ctx, platforms)
 		}
 		if err != nil {
+			debugLog("[AccountScheduling] listSchedulableAccounts FAILED: groupID=%v platform=%s err=%v", derefGroupID(groupID), platform, err)
 			return nil, useMixed, err
 		}
 		filtered := make([]Account, 0, len(accounts))
@@ -1109,6 +1134,12 @@ func (s *GatewayService) listSchedulableAccounts(ctx context.Context, groupID *i
 			}
 			filtered = append(filtered, acc)
 		}
+		debugLog("[AccountScheduling] listSchedulableAccounts (mixed): groupID=%v platform=%s rawCount=%d filteredCount=%d",
+			derefGroupID(groupID), platform, len(accounts), len(filtered))
+		for _, acc := range filtered {
+			debugLog("[AccountScheduling]   - Account ID=%d Name=%s Platform=%s Type=%s Status=%s TLSFingerprint=%v",
+				acc.ID, acc.Name, acc.Platform, acc.Type, acc.Status, acc.IsTLSFingerprintEnabled())
+		}
 		return filtered, useMixed, nil
 	}
 
@@ -1123,8 +1154,15 @@ func (s *GatewayService) listSchedulableAccounts(ctx context.Context, groupID *i
 		accounts, err = s.accountRepo.ListSchedulableByPlatform(ctx, platform)
 	}
 	if err != nil {
+		debugLog("[AccountScheduling] listSchedulableAccounts FAILED: groupID=%v platform=%s err=%v", derefGroupID(groupID), platform, err)
 		return nil, useMixed, err
 	}
+	debugLog("[AccountScheduling] listSchedulableAccounts (single): groupID=%v platform=%s count=%d",
+		derefGroupID(groupID), platform, len(accounts))
+	for _, acc := range accounts {
+		debugLog("[AccountScheduling]   - Account ID=%d Name=%s Platform=%s Type=%s Status=%s TLSFingerprint=%v",
+			acc.ID, acc.Name, acc.Platform, acc.Type, acc.Status, acc.IsTLSFingerprintEnabled())
+	}
 	return accounts, useMixed, nil
 }
 
@@ -2129,6 +2167,10 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 		proxyURL = account.Proxy.URL()
 	}
 
+	// 调试日志：记录即将转发的账号信息
+	log.Printf("[Forward] Using account: ID=%d Name=%s Platform=%s Type=%s TLSFingerprint=%v Proxy=%s",
+		account.ID, account.Name, account.Platform, account.Type, account.IsTLSFingerprintEnabled(), proxyURL)
+
 	// 重试循环
 	var resp *http.Response
 	retryStart := time.Now()
@@ -2143,7 +2185,7 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 		}
 
 		// 发送请求
-		resp, err = s.httpUpstream.Do(upstreamReq, proxyURL, account.ID, account.Concurrency)
+		resp, err = s.httpUpstream.DoWithTLS(upstreamReq, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 		if err != nil {
 			if resp != nil && resp.Body != nil {
 				_ = resp.Body.Close()
@@ -2217,7 +2259,7 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 					filteredBody := FilterThinkingBlocksForRetry(body)
 					retryReq, buildErr := s.buildUpstreamRequest(ctx, c, account, filteredBody, token, tokenType, reqModel)
 					if buildErr == nil {
-						retryResp, retryErr := s.httpUpstream.Do(retryReq, proxyURL, account.ID, account.Concurrency)
+						retryResp, retryErr := s.httpUpstream.DoWithTLS(retryReq, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 						if retryErr == nil {
 							if retryResp.StatusCode < 400 {
 								log.Printf("Account %d: signature error retry succeeded (thinking downgraded)", account.ID)
@@ -2249,7 +2291,7 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 									filteredBody2 := FilterSignatureSensitiveBlocksForRetry(body)
 									retryReq2, buildErr2 := s.buildUpstreamRequest(ctx, c, account, filteredBody2, token, tokenType, reqModel)
 									if buildErr2 == nil {
-										retryResp2, retryErr2 := s.httpUpstream.Do(retryReq2, proxyURL, account.ID, account.Concurrency)
+										retryResp2, retryErr2 := s.httpUpstream.DoWithTLS(retryReq2, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 										if retryErr2 == nil {
 											resp = retryResp2
 											break
@@ -2364,6 +2406,10 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 			_ = resp.Body.Close()
 			resp.Body = io.NopCloser(bytes.NewReader(respBody))
 
+			// 调试日志：打印重试耗尽后的错误响应
+			log.Printf("[Forward] Upstream error (retry exhausted, failover): Account=%d(%s) Status=%d RequestID=%s Body=%s",
+				account.ID, account.Name, resp.StatusCode, resp.Header.Get("x-request-id"), truncateString(string(respBody), 1000))
+
 			s.handleRetryExhaustedSideEffects(ctx, resp, account)
 			appendOpsUpstreamError(c, OpsUpstreamErrorEvent{
 				Platform:           account.Platform,
@@ -2391,6 +2437,10 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 		_ = resp.Body.Close()
 		resp.Body = io.NopCloser(bytes.NewReader(respBody))
 
+		// 调试日志：打印上游错误响应
+		log.Printf("[Forward] Upstream error (failover): Account=%d(%s) Status=%d RequestID=%s Body=%s",
+			account.ID, account.Name, resp.StatusCode, resp.Header.Get("x-request-id"), truncateString(string(respBody), 1000))
+
 		s.handleFailoverSideEffects(ctx, resp, account)
 		appendOpsUpstreamError(c, OpsUpstreamErrorEvent{
 			Platform:           account.Platform,
@@ -2741,6 +2791,10 @@ func extractUpstreamErrorMessage(body []byte) string {
 func (s *GatewayService) handleErrorResponse(ctx context.Context, resp *http.Response, c *gin.Context, account *Account) (*ForwardResult, error) {
 	body, _ := io.ReadAll(io.LimitReader(resp.Body, 2<<20))
 
+	// 调试日志：打印上游错误响应
+	log.Printf("[Forward] Upstream error (non-retryable): Account=%d(%s) Status=%d RequestID=%s Body=%s",
+		account.ID, account.Name, resp.StatusCode, resp.Header.Get("x-request-id"), truncateString(string(body), 1000))
+
 	upstreamMsg := strings.TrimSpace(extractUpstreamErrorMessage(body))
 	upstreamMsg = sanitizeUpstreamErrorMessage(upstreamMsg)
 
@@ -3449,7 +3503,7 @@ func (s *GatewayService) ForwardCountTokens(ctx context.Context, c *gin.Context,
 	}
 
 	// 发送请求
-	resp, err := s.httpUpstream.Do(upstreamReq, proxyURL, account.ID, account.Concurrency)
+	resp, err := s.httpUpstream.DoWithTLS(upstreamReq, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 	if err != nil {
 		setOpsUpstreamError(c, 0, sanitizeUpstreamErrorMessage(err.Error()), "")
 		s.countTokensError(c, http.StatusBadGateway, "upstream_error", "Request failed")
@@ -3471,7 +3525,7 @@ func (s *GatewayService) ForwardCountTokens(ctx context.Context, c *gin.Context,
 		filteredBody := FilterThinkingBlocksForRetry(body)
 		retryReq, buildErr := s.buildCountTokensRequest(ctx, c, account, filteredBody, token, tokenType, reqModel)
 		if buildErr == nil {
-			retryResp, retryErr := s.httpUpstream.Do(retryReq, proxyURL, account.ID, account.Concurrency)
+			retryResp, retryErr := s.httpUpstream.DoWithTLS(retryReq, proxyURL, account.ID, account.Concurrency, account.IsTLSFingerprintEnabled())
 			if retryErr == nil {
 				resp = retryResp
 				respBody, err = io.ReadAll(resp.Body)

backend/internal/service/http_upstream_port.go

@@ -10,6 +10,7 @@ import "net/http"
 // - 支持可选代理配置
 // - 支持账户级连接池隔离
 // - 实现类负责连接池管理和复用
+// - 支持可选的 TLS 指纹伪装
 type HTTPUpstream interface {
 	// Do 执行 HTTP 请求
 	//
@@ -27,4 +28,28 @@ type HTTPUpstream interface {
 	//   - 调用方必须关闭 resp.Body，否则会导致连接泄漏
 	//   - 响应体可能已被包装以跟踪请求生命周期
 	Do(req *http.Request, proxyURL string, accountID int64, accountConcurrency int) (*http.Response, error)
+
+	// DoWithTLS 执行带 TLS 指纹伪装的 HTTP 请求
+	//
+	// 参数:
+	//   - req: HTTP 请求对象，由调用方构建
+	//   - proxyURL: 代理服务器地址，空字符串表示直连
+	//   - accountID: 账户 ID，用于连接池隔离和 TLS 指纹模板选择
+	//   - accountConcurrency: 账户并发限制，用于动态调整连接池大小
+	//   - enableTLSFingerprint: 是否启用 TLS 指纹伪装
+	//
+	// 返回:
+	//   - *http.Response: HTTP 响应，调用方必须关闭 Body
+	//   - error: 请求错误（网络错误、超时等）
+	//
+	// TLS 指纹说明:
+	//   - 当 enableTLSFingerprint=true 时，使用 utls 库模拟 Claude CLI 的 TLS 指纹
+	//   - TLS 指纹模板根据 accountID % len(profiles) 自动选择
+	//   - 支持直连、HTTP/HTTPS 代理、SOCKS5 代理三种场景
+	//   - 如果 enableTLSFingerprint=false，行为与 Do 方法相同
+	//
+	// 注意:
+	//   - 调用方必须关闭 resp.Body，否则会导致连接泄漏
+	//   - TLS 指纹客户端与普通客户端使用不同的缓存键，互不影响
+	DoWithTLS(req *http.Request, proxyURL string, accountID int64, accountConcurrency int, enableTLSFingerprint bool) (*http.Response, error)
 }

deploy/README.md

@@ -401,3 +401,58 @@ sudo systemctl status redis
 2. **Database connection failed**: Check PostgreSQL is running and credentials are correct
 3. **Redis connection failed**: Check Redis is running and password is correct
 4. **Permission denied**: Ensure proper file ownership for binary install
+
+---
+
+## TLS Fingerprint Configuration
+
+Sub2API supports TLS fingerprint simulation to make requests appear as if they come from the official Claude CLI (Node.js client).
+
+### Default Behavior
+
+- Built-in `claude_cli_v2` profile simulates Node.js 20.x + OpenSSL 3.x
+- JA3 Hash: `1a28e69016765d92e3b381168d68922c`
+- JA4: `t13d5911h1_a33745022dd6_1f22a2ca17c4`
+- Profile selection: `accountID % profileCount`
+
+### Configuration
+
+```yaml
+gateway:
+  tls_fingerprint:
+    enabled: true  # Global switch
+    profiles:
+      # Simple profile (uses default cipher suites)
+      profile_1:
+        name: "Profile 1"
+
+      # Profile with custom cipher suites (use compact array format)
+      profile_2:
+        name: "Profile 2"
+        cipher_suites: [4866, 4867, 4865, 49199, 49195, 49200, 49196]
+        curves: [29, 23, 24]
+        point_formats: [0]
+
+      # Another custom profile
+      profile_3:
+        name: "Profile 3"
+        cipher_suites: [4865, 4866, 4867, 49199, 49200]
+        curves: [29, 23, 24, 25]
+```
+
+### Profile Fields
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `name` | string | Display name (required) |
+| `cipher_suites` | []uint16 | Cipher suites in decimal. Empty = default |
+| `curves` | []uint16 | Elliptic curves in decimal. Empty = default |
+| `point_formats` | []uint8 | EC point formats. Empty = default |
+
+### Common Values Reference
+
+**Cipher Suites (TLS 1.3):** `4865` (AES_128_GCM), `4866` (AES_256_GCM), `4867` (CHACHA20)
+
+**Cipher Suites (TLS 1.2):** `49195`, `49196`, `49199`, `49200` (ECDHE variants)
+
+**Curves:** `29` (X25519), `23` (P-256), `24` (P-384), `25` (P-521)

deploy/config.example.yaml

@@ -210,6 +210,19 @@ gateway:
     outbox_backlog_rebuild_rows: 10000
     # 全量重建周期（秒），0 表示禁用
     full_rebuild_interval_seconds: 300
+  # TLS fingerprint simulation / TLS 指纹伪装
+  # Default profile "claude_cli_v2" simulates Node.js 20.x
+  # 默认模板 "claude_cli_v2" 模拟 Node.js 20.x 指纹
+  tls_fingerprint:
+    enabled: true
+    # profiles:
+    #   profile_1:
+    #     name: "Custom Profile 1"
+    #   profile_2:
+    #     name: "Custom Profile 2"
+    #     cipher_suites: [4866, 4867, 4865, 49199, 49195, 49200, 49196]
+    #     curves: [29, 23, 24]
+    #     point_formats: [0]
 
 # =============================================================================
 # API Key Auth Cache Configuration

frontend/src/components/account/CreateAccountModal.vue

@@ -1319,6 +1319,33 @@
             </div>
           </div>
         </div>
+
+        <!-- TLS Fingerprint -->
+        <div class="rounded-lg border border-gray-200 p-4 dark:border-dark-600">
+          <div class="flex items-center justify-between">
+            <div>
+              <label class="input-label mb-0">{{ t('admin.accounts.quotaControl.tlsFingerprint.label') }}</label>
+              <p class="mt-1 text-xs text-gray-500 dark:text-gray-400">
+                {{ t('admin.accounts.quotaControl.tlsFingerprint.hint') }}
+              </p>
+            </div>
+            <button
+              type="button"
+              @click="tlsFingerprintEnabled = !tlsFingerprintEnabled"
+              :class="[
+                'relative inline-flex h-6 w-11 flex-shrink-0 cursor-pointer rounded-full border-2 border-transparent transition-colors duration-200 ease-in-out focus:outline-none focus:ring-2 focus:ring-primary-500 focus:ring-offset-2',
+                tlsFingerprintEnabled ? 'bg-primary-600' : 'bg-gray-200 dark:bg-dark-600'
+              ]"
+            >
+              <span
+                :class="[
+                  'pointer-events-none inline-block h-5 w-5 transform rounded-full bg-white shadow ring-0 transition duration-200 ease-in-out',
+                  tlsFingerprintEnabled ? 'translate-x-5' : 'translate-x-0'
+                ]"
+              />
+            </button>
+          </div>
+        </div>
       </div>
 
       <div>
@@ -1900,6 +1927,7 @@ const windowCostStickyReserve = ref<number | null>(null)
 const sessionLimitEnabled = ref(false)
 const maxSessions = ref<number | null>(null)
 const sessionIdleTimeout = ref<number | null>(null)
+const tlsFingerprintEnabled = ref(false)
 
 // Gemini tier selection (used as fallback when auto-detection is unavailable/fails)
 const geminiTierGoogleOne = ref<'google_one_free' | 'google_ai_pro' | 'google_ai_ultra'>('google_one_free')
@@ -2285,6 +2313,7 @@ const resetForm = () => {
   sessionLimitEnabled.value = false
   maxSessions.value = null
   sessionIdleTimeout.value = null
+  tlsFingerprintEnabled.value = false
   tempUnschedEnabled.value = false
   tempUnschedRules.value = []
   geminiOAuthType.value = 'code_assist'
@@ -2568,6 +2597,11 @@ const handleAnthropicExchange = async (authCode: string) => {
       extra.session_idle_timeout_minutes = sessionIdleTimeout.value ?? 5
     }
 
+    // Add TLS fingerprint settings
+    if (tlsFingerprintEnabled.value) {
+      extra.enable_tls_fingerprint = true
+    }
+
     const credentials = {
       ...tokenInfo,
       ...(interceptWarmupRequests.value ? { intercept_warmup_requests: true } : {})
@@ -2651,6 +2685,11 @@ const handleCookieAuth = async (sessionKey: string) => {
           extra.session_idle_timeout_minutes = sessionIdleTimeout.value ?? 5
         }
 
+        // Add TLS fingerprint settings
+        if (tlsFingerprintEnabled.value) {
+          extra.enable_tls_fingerprint = true
+        }
+
         const accountName = keys.length > 1 ? `${form.name} #${i + 1}` : form.name
 
         // Merge interceptWarmupRequests into credentials

frontend/src/components/account/EditAccountModal.vue

@@ -732,6 +732,33 @@
             </div>
           </div>
         </div>
+
+        <!-- TLS Fingerprint -->
+        <div class="rounded-lg border border-gray-200 p-4 dark:border-dark-600">
+          <div class="flex items-center justify-between">
+            <div>
+              <label class="input-label mb-0">{{ t('admin.accounts.quotaControl.tlsFingerprint.label') }}</label>
+              <p class="mt-1 text-xs text-gray-500 dark:text-gray-400">
+                {{ t('admin.accounts.quotaControl.tlsFingerprint.hint') }}
+              </p>
+            </div>
+            <button
+              type="button"
+              @click="tlsFingerprintEnabled = !tlsFingerprintEnabled"
+              :class="[
+                'relative inline-flex h-6 w-11 flex-shrink-0 cursor-pointer rounded-full border-2 border-transparent transition-colors duration-200 ease-in-out focus:outline-none focus:ring-2 focus:ring-primary-500 focus:ring-offset-2',
+                tlsFingerprintEnabled ? 'bg-primary-600' : 'bg-gray-200 dark:bg-dark-600'
+              ]"
+            >
+              <span
+                :class="[
+                  'pointer-events-none inline-block h-5 w-5 transform rounded-full bg-white shadow ring-0 transition duration-200 ease-in-out',
+                  tlsFingerprintEnabled ? 'translate-x-5' : 'translate-x-0'
+                ]"
+              />
+            </button>
+          </div>
+        </div>
       </div>
 
       <div class="border-t border-gray-200 pt-4 dark:border-dark-600">
@@ -904,6 +931,7 @@ const windowCostStickyReserve = ref<number | null>(null)
 const sessionLimitEnabled = ref(false)
 const maxSessions = ref<number | null>(null)
 const sessionIdleTimeout = ref<number | null>(null)
+const tlsFingerprintEnabled = ref(false)
 
 // Computed: current preset mappings based on platform
 const presetMappings = computed(() => getPresetMappingsByPlatform(props.account?.platform || 'anthropic'))
@@ -1237,6 +1265,7 @@ function loadQuotaControlSettings(account: Account) {
   sessionLimitEnabled.value = false
   maxSessions.value = null
   sessionIdleTimeout.value = null
+  tlsFingerprintEnabled.value = false
 
   // Only applies to Anthropic OAuth/SetupToken accounts
   if (account.platform !== 'anthropic' || (account.type !== 'oauth' && account.type !== 'setup-token')) {
@@ -1255,6 +1284,11 @@ function loadQuotaControlSettings(account: Account) {
     maxSessions.value = account.max_sessions
     sessionIdleTimeout.value = account.session_idle_timeout_minutes ?? 5
   }
+
+  // Load TLS fingerprint setting
+  if (account.enable_tls_fingerprint === true) {
+    tlsFingerprintEnabled.value = true
+  }
 }
 
 function formatTempUnschedKeywords(value: unknown) {
@@ -1407,6 +1441,13 @@ const handleSubmit = async () => {
         delete newExtra.session_idle_timeout_minutes
       }
 
+      // TLS fingerprint setting
+      if (tlsFingerprintEnabled.value) {
+        newExtra.enable_tls_fingerprint = true
+      } else {
+        delete newExtra.enable_tls_fingerprint
+      }
+
       updatePayload.extra = newExtra
     }
 

frontend/src/i18n/locales/en.ts

@@ -1285,6 +1285,10 @@ export default {
           idleTimeout: 'Idle Timeout',
           idleTimeoutPlaceholder: '5',
           idleTimeoutHint: 'Sessions will be released after idle timeout'
+        },
+        tlsFingerprint: {
+          label: 'TLS Fingerprint Simulation',
+          hint: 'Simulate Node.js/Claude Code client TLS fingerprint'
         }
       },
       expired: 'Expired',

frontend/src/i18n/locales/zh.ts

@@ -1417,6 +1417,10 @@ export default {
           idleTimeout: '空闲超时',
           idleTimeoutPlaceholder: '5',
           idleTimeoutHint: '会话空闲超时后自动释放'
+        },
+        tlsFingerprint: {
+          label: 'TLS 指纹模拟',
+          hint: '模拟 Node.js/Claude Code 客户端的 TLS 指纹'
         }
       },
       expired: '已过期',

frontend/src/types/index.ts

@@ -480,6 +480,9 @@ export interface Account {
   max_sessions?: number | null
   session_idle_timeout_minutes?: number | null
 
+  // TLS指纹伪装（仅 Anthropic OAuth/SetupToken 账号有效）
+  enable_tls_fingerprint?: boolean | null
+
   // 运行时状态（仅当启用对应限制时返回）
   current_window_cost?: number | null // 当前窗口费用
   active_sessions?: number | null // 当前活跃会话数

frontend/tsconfig.json

@@ -21,5 +21,6 @@
     "types": ["vite/client"]
   },
   "include": ["src/**/*.ts", "src/**/*.tsx", "src/**/*.vue"],
+  "exclude": ["src/**/__tests__/**", "src/**/*.spec.ts", "src/**/*.test.ts"],
   "references": [{ "path": "./tsconfig.node.json" }]
 }