feat(auth): add proxy URL override support to auth constructors and executors

- Introduced `WithProxyURL` variants for `CodexAuth`, `ClaudeAuth`, `IFlowAuth`, and `DeviceFlowClient`.
- Updated executors to use proxy-aware constructors for improved configurability.
- Added unit tests to validate proxy override precedence and functionality.

Closes: #2823

internal/auth/claude/anthropic_auth.go

@@ -59,10 +59,30 @@ type ClaudeAuth struct {
 // Returns:
 //   - *ClaudeAuth: A new Claude authentication service instance
 func NewClaudeAuth(cfg *config.Config) *ClaudeAuth {
+	return NewClaudeAuthWithProxyURL(cfg, "")
+}
+
+// NewClaudeAuthWithProxyURL creates a new Anthropic authentication service with a proxy override.
+// proxyURL takes precedence over cfg.ProxyURL when non-empty.
+func NewClaudeAuthWithProxyURL(cfg *config.Config, proxyURL string) *ClaudeAuth {
+	effectiveProxyURL := strings.TrimSpace(proxyURL)
+	var sdkCfg *config.SDKConfig
+	if cfg != nil {
+		sdkCfgCopy := cfg.SDKConfig
+		if effectiveProxyURL == "" {
+			effectiveProxyURL = strings.TrimSpace(cfg.ProxyURL)
+		}
+		sdkCfgCopy.ProxyURL = effectiveProxyURL
+		sdkCfg = &sdkCfgCopy
+	} else if effectiveProxyURL != "" {
+		sdkCfgCopy := config.SDKConfig{ProxyURL: effectiveProxyURL}
+		sdkCfg = &sdkCfgCopy
+	}
+
 	// Use custom HTTP client with Firefox TLS fingerprint to bypass
 	// Cloudflare's bot detection on Anthropic domains
 	return &ClaudeAuth{
-		httpClient: NewAnthropicHttpClient(&cfg.SDKConfig),
+		httpClient: NewAnthropicHttpClient(sdkCfg),
 	}
 }
 

internal/auth/claude/anthropic_auth_proxy_test.go

@@ -0,0 +1,33 @@
+package claude
+
+import (
+	"testing"
+
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
+	"golang.org/x/net/proxy"
+)
+
+func TestNewClaudeAuthWithProxyURL_OverrideDirectTakesPrecedence(t *testing.T) {
+	cfg := &config.Config{SDKConfig: config.SDKConfig{ProxyURL: "socks5://proxy.example.com:1080"}}
+	auth := NewClaudeAuthWithProxyURL(cfg, "direct")
+
+	transport, ok := auth.httpClient.Transport.(*utlsRoundTripper)
+	if !ok || transport == nil {
+		t.Fatalf("expected utlsRoundTripper, got %T", auth.httpClient.Transport)
+	}
+	if transport.dialer != proxy.Direct {
+		t.Fatalf("expected proxy.Direct, got %T", transport.dialer)
+	}
+}
+
+func TestNewClaudeAuthWithProxyURL_OverrideProxyAppliedWithoutConfig(t *testing.T) {
+	auth := NewClaudeAuthWithProxyURL(nil, "socks5://proxy.example.com:1080")
+
+	transport, ok := auth.httpClient.Transport.(*utlsRoundTripper)
+	if !ok || transport == nil {
+		t.Fatalf("expected utlsRoundTripper, got %T", auth.httpClient.Transport)
+	}
+	if transport.dialer == proxy.Direct {
+		t.Fatalf("expected proxy dialer, got %T", transport.dialer)
+	}
+}

internal/auth/codex/openai_auth.go

@@ -37,8 +37,23 @@ type CodexAuth struct {
 // NewCodexAuth creates a new CodexAuth service instance.
 // It initializes an HTTP client with proxy settings from the provided configuration.
 func NewCodexAuth(cfg *config.Config) *CodexAuth {
+	return NewCodexAuthWithProxyURL(cfg, "")
+}
+
+// NewCodexAuthWithProxyURL creates a new CodexAuth service instance.
+// proxyURL takes precedence over cfg.ProxyURL when non-empty.
+func NewCodexAuthWithProxyURL(cfg *config.Config, proxyURL string) *CodexAuth {
+	effectiveProxyURL := strings.TrimSpace(proxyURL)
+	var sdkCfg config.SDKConfig
+	if cfg != nil {
+		sdkCfg = cfg.SDKConfig
+		if effectiveProxyURL == "" {
+			effectiveProxyURL = strings.TrimSpace(cfg.ProxyURL)
+		}
+	}
+	sdkCfg.ProxyURL = effectiveProxyURL
 	return &CodexAuth{
-		httpClient: util.SetProxy(&cfg.SDKConfig, &http.Client{}),
+		httpClient: util.SetProxy(&sdkCfg, &http.Client{}),
 	}
 }
 

internal/auth/codex/openai_auth_test.go

@@ -7,6 +7,8 @@ import (
 	"strings"
 	"sync/atomic"
 	"testing"
+
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
 )
 
 type roundTripFunc func(*http.Request) (*http.Response, error)
@@ -42,3 +44,37 @@ func TestRefreshTokensWithRetry_NonRetryableOnlyAttemptsOnce(t *testing.T) {
 		t.Fatalf("expected 1 refresh attempt, got %d", got)
 	}
 }
+
+func TestNewCodexAuthWithProxyURL_OverrideDirectDisablesProxy(t *testing.T) {
+	cfg := &config.Config{SDKConfig: config.SDKConfig{ProxyURL: "http://proxy.example.com:8080"}}
+	auth := NewCodexAuthWithProxyURL(cfg, "direct")
+
+	transport, ok := auth.httpClient.Transport.(*http.Transport)
+	if !ok || transport == nil {
+		t.Fatalf("expected http.Transport, got %T", auth.httpClient.Transport)
+	}
+	if transport.Proxy != nil {
+		t.Fatal("expected direct transport to disable proxy function")
+	}
+}
+
+func TestNewCodexAuthWithProxyURL_OverrideProxyTakesPrecedence(t *testing.T) {
+	cfg := &config.Config{SDKConfig: config.SDKConfig{ProxyURL: "http://global.example.com:8080"}}
+	auth := NewCodexAuthWithProxyURL(cfg, "http://override.example.com:8081")
+
+	transport, ok := auth.httpClient.Transport.(*http.Transport)
+	if !ok || transport == nil {
+		t.Fatalf("expected http.Transport, got %T", auth.httpClient.Transport)
+	}
+	req, errReq := http.NewRequest(http.MethodGet, "https://example.com", nil)
+	if errReq != nil {
+		t.Fatalf("new request: %v", errReq)
+	}
+	proxyURL, errProxy := transport.Proxy(req)
+	if errProxy != nil {
+		t.Fatalf("proxy func: %v", errProxy)
+	}
+	if proxyURL == nil || proxyURL.String() != "http://override.example.com:8081" {
+		t.Fatalf("proxy URL = %v, want http://override.example.com:8081", proxyURL)
+	}
+}

internal/auth/iflow/iflow_auth.go

@@ -48,8 +48,23 @@ type IFlowAuth struct {
 
 // NewIFlowAuth constructs a new IFlowAuth with proxy-aware transport.
 func NewIFlowAuth(cfg *config.Config) *IFlowAuth {
+	return NewIFlowAuthWithProxyURL(cfg, "")
+}
+
+// NewIFlowAuthWithProxyURL constructs a new IFlowAuth with a proxy override.
+// proxyURL takes precedence over cfg.ProxyURL when non-empty.
+func NewIFlowAuthWithProxyURL(cfg *config.Config, proxyURL string) *IFlowAuth {
 	client := &http.Client{Timeout: 30 * time.Second}
-	return &IFlowAuth{httpClient: util.SetProxy(&cfg.SDKConfig, client)}
+	effectiveProxyURL := strings.TrimSpace(proxyURL)
+	var sdkCfg config.SDKConfig
+	if cfg != nil {
+		sdkCfg = cfg.SDKConfig
+		if effectiveProxyURL == "" {
+			effectiveProxyURL = strings.TrimSpace(cfg.ProxyURL)
+		}
+	}
+	sdkCfg.ProxyURL = effectiveProxyURL
+	return &IFlowAuth{httpClient: util.SetProxy(&sdkCfg, client)}
 }
 
 // AuthorizationURL builds the authorization URL and matching redirect URI.

internal/auth/iflow/iflow_auth_test.go

@@ -0,0 +1,42 @@
+package iflow
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
+)
+
+func TestNewIFlowAuthWithProxyURL_OverrideDirectDisablesProxy(t *testing.T) {
+	cfg := &config.Config{SDKConfig: config.SDKConfig{ProxyURL: "http://proxy.example.com:8080"}}
+	auth := NewIFlowAuthWithProxyURL(cfg, "direct")
+
+	transport, ok := auth.httpClient.Transport.(*http.Transport)
+	if !ok || transport == nil {
+		t.Fatalf("expected http.Transport, got %T", auth.httpClient.Transport)
+	}
+	if transport.Proxy != nil {
+		t.Fatal("expected direct transport to disable proxy function")
+	}
+}
+
+func TestNewIFlowAuthWithProxyURL_OverrideProxyTakesPrecedence(t *testing.T) {
+	cfg := &config.Config{SDKConfig: config.SDKConfig{ProxyURL: "http://global.example.com:8080"}}
+	auth := NewIFlowAuthWithProxyURL(cfg, "http://override.example.com:8081")
+
+	transport, ok := auth.httpClient.Transport.(*http.Transport)
+	if !ok || transport == nil {
+		t.Fatalf("expected http.Transport, got %T", auth.httpClient.Transport)
+	}
+	req, errReq := http.NewRequest(http.MethodGet, "https://example.com", nil)
+	if errReq != nil {
+		t.Fatalf("new request: %v", errReq)
+	}
+	proxyURL, errProxy := transport.Proxy(req)
+	if errProxy != nil {
+		t.Fatalf("proxy func: %v", errProxy)
+	}
+	if proxyURL == nil || proxyURL.String() != "http://override.example.com:8081" {
+		t.Fatalf("proxy URL = %v, want http://override.example.com:8081", proxyURL)
+	}
+}

internal/auth/kimi/kimi.go

@@ -102,10 +102,24 @@ func NewDeviceFlowClient(cfg *config.Config) *DeviceFlowClient {
 
 // NewDeviceFlowClientWithDeviceID creates a new device flow client with the specified device ID.
 func NewDeviceFlowClientWithDeviceID(cfg *config.Config, deviceID string) *DeviceFlowClient {
+	return NewDeviceFlowClientWithDeviceIDAndProxyURL(cfg, deviceID, "")
+}
+
+// NewDeviceFlowClientWithDeviceIDAndProxyURL creates a new device flow client with a proxy override.
+// proxyURL takes precedence over cfg.ProxyURL when non-empty.
+func NewDeviceFlowClientWithDeviceIDAndProxyURL(cfg *config.Config, deviceID string, proxyURL string) *DeviceFlowClient {
 	client := &http.Client{Timeout: 30 * time.Second}
+	effectiveProxyURL := strings.TrimSpace(proxyURL)
+	var sdkCfg config.SDKConfig
 	if cfg != nil {
-		client = util.SetProxy(&cfg.SDKConfig, client)
+		sdkCfg = cfg.SDKConfig
+		if effectiveProxyURL == "" {
+			effectiveProxyURL = strings.TrimSpace(cfg.ProxyURL)
 		}
+	}
+	sdkCfg.ProxyURL = effectiveProxyURL
+	client = util.SetProxy(&sdkCfg, client)
+
 	resolvedDeviceID := strings.TrimSpace(deviceID)
 	if resolvedDeviceID == "" {
 		resolvedDeviceID = getOrCreateDeviceID()

internal/auth/kimi/kimi_proxy_test.go

@@ -0,0 +1,42 @@
+package kimi
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
+)
+
+func TestNewDeviceFlowClientWithDeviceIDAndProxyURL_OverrideDirectDisablesProxy(t *testing.T) {
+	cfg := &config.Config{SDKConfig: config.SDKConfig{ProxyURL: "http://proxy.example.com:8080"}}
+	client := NewDeviceFlowClientWithDeviceIDAndProxyURL(cfg, "device-1", "direct")
+
+	transport, ok := client.httpClient.Transport.(*http.Transport)
+	if !ok || transport == nil {
+		t.Fatalf("expected http.Transport, got %T", client.httpClient.Transport)
+	}
+	if transport.Proxy != nil {
+		t.Fatal("expected direct transport to disable proxy function")
+	}
+}
+
+func TestNewDeviceFlowClientWithDeviceIDAndProxyURL_OverrideProxyTakesPrecedence(t *testing.T) {
+	cfg := &config.Config{SDKConfig: config.SDKConfig{ProxyURL: "http://global.example.com:8080"}}
+	client := NewDeviceFlowClientWithDeviceIDAndProxyURL(cfg, "device-1", "http://override.example.com:8081")
+
+	transport, ok := client.httpClient.Transport.(*http.Transport)
+	if !ok || transport == nil {
+		t.Fatalf("expected http.Transport, got %T", client.httpClient.Transport)
+	}
+	req, errReq := http.NewRequest(http.MethodGet, "https://example.com", nil)
+	if errReq != nil {
+		t.Fatalf("new request: %v", errReq)
+	}
+	proxyURL, errProxy := transport.Proxy(req)
+	if errProxy != nil {
+		t.Fatalf("proxy func: %v", errProxy)
+	}
+	if proxyURL == nil || proxyURL.String() != "http://override.example.com:8081" {
+		t.Fatalf("proxy URL = %v, want http://override.example.com:8081", proxyURL)
+	}
+}

internal/runtime/executor/claude_executor.go

@@ -659,7 +659,7 @@ func (e *ClaudeExecutor) Refresh(ctx context.Context, auth *cliproxyauth.Auth) (
 	if refreshToken == "" {
 		return auth, nil
 	}
-	svc := claudeauth.NewClaudeAuth(e.cfg)
+	svc := claudeauth.NewClaudeAuthWithProxyURL(e.cfg, auth.ProxyURL)
 	td, err := svc.RefreshTokens(ctx, refreshToken)
 	if err != nil {
 		return nil, err

internal/runtime/executor/codex_executor.go

@@ -612,7 +612,7 @@ func (e *CodexExecutor) Refresh(ctx context.Context, auth *cliproxyauth.Auth) (*
 	if refreshToken == "" {
 		return auth, nil
 	}
-	svc := codexauth.NewCodexAuth(e.cfg)
+	svc := codexauth.NewCodexAuthWithProxyURL(e.cfg, auth.ProxyURL)
 	td, err := svc.RefreshTokensWithRetry(ctx, refreshToken, 3)
 	if err != nil {
 		return nil, err

internal/runtime/executor/iflow_executor.go

@@ -381,7 +381,7 @@ func (e *IFlowExecutor) refreshCookieBased(ctx context.Context, auth *cliproxyau
 
 	log.Infof("iflow executor: refreshing cookie-based API key for user: %s", email)
 
-	svc := iflowauth.NewIFlowAuth(e.cfg)
+	svc := iflowauth.NewIFlowAuthWithProxyURL(e.cfg, auth.ProxyURL)
 	keyData, err := svc.RefreshAPIKey(ctx, cookie, email)
 	if err != nil {
 		log.Errorf("iflow executor: cookie-based API key refresh failed: %v", err)
@@ -429,7 +429,7 @@ func (e *IFlowExecutor) refreshOAuthBased(ctx context.Context, auth *cliproxyaut
 		log.Debugf("iflow executor: refreshing access token, old: %s", util.HideAPIKey(oldAccessToken))
 	}
 
-	svc := iflowauth.NewIFlowAuth(e.cfg)
+	svc := iflowauth.NewIFlowAuthWithProxyURL(e.cfg, auth.ProxyURL)
 	tokenData, err := svc.RefreshTokens(ctx, refreshToken)
 	if err != nil {
 		log.Errorf("iflow executor: token refresh failed: %v", err)

internal/runtime/executor/kimi_executor.go

@@ -472,7 +472,7 @@ func (e *KimiExecutor) Refresh(ctx context.Context, auth *cliproxyauth.Auth) (*c
 		return auth, nil
 	}
 
-	client := kimiauth.NewDeviceFlowClientWithDeviceID(e.cfg, resolveKimiDeviceID(auth))
+	client := kimiauth.NewDeviceFlowClientWithDeviceIDAndProxyURL(e.cfg, resolveKimiDeviceID(auth), auth.ProxyURL)
 	td, err := client.RefreshToken(ctx, refreshToken)
 	if err != nil {
 		return nil, err