feat: 添加服务端证书合法性验证（自定义CA/跳过验证/证书固定）

- 新增 internal/tlsconfig 包，集中构建 TLS 配置
- 修复 CDN 边缘 IP 故障转移时 HTTP 登录 TLS 验证失败的问题
- 支持自定义 CA 证书（内联 PEM + 文件路径，合并生效）
- 支持 InsecureSkipVerify 跳过证书验证
- 支持证书固定（SHA-256 指纹校验）
- TLS 验证错误设为不可恢复，避免无限重试
- Profile 编辑界面新增 TLS 设置区域，协议联动启用/禁用
- DB schema v4 迁移，新增 4 个 TLS 字段

Makefile

@@ -11,7 +11,7 @@ GO          = go
 CGO_ENABLED = 1
 WINDRES     ?= x86_64-w64-mingw32-windres
 MINGW_CC    ?= x86_64-w64-mingw32-gcc
-SEMVER      ?= 0.3.9
+SEMVER      ?= 0.4.1
 GIT_HASH    = $(shell git rev-parse --short HEAD 2>/dev/null || echo unknown)
 VERSION     = $(SEMVER)-$(GIT_HASH)
 LDFLAGS     = -s -w -X lmvpn/internal/version.Version=$(VERSION)

internal/auth/auth.go

@@ -6,6 +6,7 @@ package auth
 
 import (
 	"bytes"
+	"crypto/tls"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -41,7 +42,12 @@ type errorResponse struct {
 // baseURL should be the HTTP(S) origin derived from the WebSocket URL
 // (e.g. "http://localhost:8080" for ws://, "https://vpn.example.com"
 // for wss://). See WSURLToHTTP.
-func Login(baseURL, username, password string) (*LoginResult, error) {
+//
+// tlsCfg, if non-nil, is used as the TLS configuration for the HTTP
+// client. This is essential when connecting via CDN edge IPs: the URL
+// host will be an IP address, but the certificate must be verified
+// against the real hostname (set tlsCfg.ServerName).
+func Login(baseURL, username, password string, tlsCfg *tls.Config) (*LoginResult, error) {
 	body, err := json.Marshal(loginRequest{Username: username, Password: password})
 	if err != nil {
 		return nil, err
@@ -49,6 +55,9 @@ func Login(baseURL, username, password string) (*LoginResult, error) {
 
 	url := strings.TrimRight(baseURL, "/") + "/api/login"
 	client := &http.Client{Timeout: 15 * time.Second}
+	if tlsCfg != nil {
+		client.Transport = &http.Transport{TLSClientConfig: tlsCfg}
+	}
 	resp, err := client.Post(url, "application/json", bytes.NewReader(body))
 	if err != nil {
 		return nil, fmt.Errorf("login request: %w", err)

internal/daemon/daemon.go

@@ -131,16 +131,20 @@ func (d *daemon) startSession(conn net.Conn, req ipc.Request) {
 	}
 
 	cfg := vpn.SessionConfig{
-		ServerURL:   req.Config.ServerURL,
-		SNIHost:     req.Config.SNIHost,
-		ServerIPs:   req.Config.ServerIPs,
-		Username:    req.Config.Username,
-		Password:    req.Config.Password,
-		Token:       req.Config.Token,
-		AuthMode:    model.AuthMode(req.Config.AuthMode),
-		RoutingMode: ipc.RoutingModeFromIPC(req.Config.RoutingMode),
-		CustomCIDRs: req.Config.CustomCIDRs,
-		MTUOverride: req.Config.MTUOverride,
+		ServerURL:     req.Config.ServerURL,
+		SNIHost:       req.Config.SNIHost,
+		ServerIPs:     req.Config.ServerIPs,
+		Username:      req.Config.Username,
+		Password:      req.Config.Password,
+		Token:         req.Config.Token,
+		AuthMode:      model.AuthMode(req.Config.AuthMode),
+		RoutingMode:   ipc.RoutingModeFromIPC(req.Config.RoutingMode),
+		CustomCIDRs:   req.Config.CustomCIDRs,
+		MTUOverride:   req.Config.MTUOverride,
+		TLSCACert:     req.Config.TLSCACert,
+		TLSCAPath:     req.Config.TLSCAPath,
+		TLSInsecure:   req.Config.TLSInsecure,
+		TLSPinnedHash: req.Config.TLSPinnedHash,
 	}
 
 	ctx, cancel := context.WithCancel(context.Background())

internal/db/db.go

@@ -48,7 +48,10 @@ func (s *Store) migrate() error {
 	if err := s.migrateV2(); err != nil {
 		return err
 	}
-	return s.migrateV3()
+	if err := s.migrateV3(); err != nil {
+		return err
+	}
+	return s.migrateV4()
 }
 
 func (s *Store) migrateV2() error {
@@ -181,6 +184,29 @@ func (s *Store) migrateV3() error {
 	return nil
 }
 
+// migrateV4 adds TLS certificate verification columns to
+// server_profiles for custom CA, insecure mode, and cert pinning.
+// Idempotent: skips columns that already exist.
+func (s *Store) migrateV4() error {
+	cols := []struct {
+		name string
+		sql  string
+	}{
+		{"tls_ca_cert", "ALTER TABLE server_profiles ADD COLUMN tls_ca_cert TEXT NOT NULL DEFAULT ''"},
+		{"tls_ca_path", "ALTER TABLE server_profiles ADD COLUMN tls_ca_path TEXT NOT NULL DEFAULT ''"},
+		{"tls_insecure", "ALTER TABLE server_profiles ADD COLUMN tls_insecure INTEGER NOT NULL DEFAULT 0"},
+		{"tls_pinned_hash", "ALTER TABLE server_profiles ADD COLUMN tls_pinned_hash TEXT NOT NULL DEFAULT ''"},
+	}
+	for _, c := range cols {
+		if !columnExists(s.db, "server_profiles", c.name) {
+			if _, err := s.db.Exec(c.sql); err != nil {
+				return fmt.Errorf("migrate v4 add %s: %w", c.name, err)
+			}
+		}
+	}
+	return nil
+}
+
 // columnExists reports whether a column exists on a table.
 func columnExists(db *sql.DB, table, column string) bool {
 	rows, err := db.Query(fmt.Sprintf("PRAGMA table_info(%s)", table))

internal/db/profile.go

@@ -14,11 +14,13 @@ func (s *Store) CreateProfile(p *model.ServerProfile) (int64, error) {
 		`INSERT INTO server_profiles
 		   (name, protocol, host, server_ips, port, path,
 		    username, auth_mode, routing_mode,
-		    custom_cidrs, mtu_override, auto_connect)
-		 VALUES (?,?,?,?,?,?,?,?,?,?,?,?)`,
+		    custom_cidrs, mtu_override, auto_connect,
+		    tls_ca_cert, tls_ca_path, tls_insecure, tls_pinned_hash)
+		 VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)`,
 		p.Name, p.Protocol, p.Host, p.ServerIPs, p.Port, p.Path,
 		p.Username, p.AuthMode, p.RoutingMode,
 		p.CustomCIDRs, p.MTUOverride, p.AutoConnect,
+		p.TLSCACert, p.TLSCAPath, p.TLSInsecure, p.TLSPinnedHash,
 	)
 	if err != nil {
 		return 0, fmt.Errorf("insert profile: %w", err)
@@ -36,11 +38,14 @@ func (s *Store) GetProfile(id int64) (*model.ServerProfile, error) {
 	err := s.db.QueryRow(
 		`SELECT id, name, protocol, host, server_ips, port, path,
 		        username, auth_mode, routing_mode,
-		        custom_cidrs, mtu_override, auto_connect, created_at, last_connected_at
+		        custom_cidrs, mtu_override, auto_connect,
+		        tls_ca_cert, tls_ca_path, tls_insecure, tls_pinned_hash,
+		        created_at, last_connected_at
 		 FROM server_profiles WHERE id = ?`, id,
 	).Scan(&p.ID, &p.Name, &p.Protocol, &p.Host, &p.ServerIPs, &p.Port, &p.Path,
 		&p.Username, &p.AuthMode, &p.RoutingMode, &p.CustomCIDRs, &p.MTUOverride,
-		&p.AutoConnect, &p.CreatedAt, &last)
+		&p.AutoConnect, &p.TLSCACert, &p.TLSCAPath, &p.TLSInsecure, &p.TLSPinnedHash,
+		&p.CreatedAt, &last)
 	if err != nil {
 		return nil, fmt.Errorf("get profile %d: %w", id, err)
 	}
@@ -55,7 +60,9 @@ func (s *Store) ListProfiles() ([]model.ServerProfile, error) {
 	rows, err := s.db.Query(
 		`SELECT id, name, protocol, host, server_ips, port, path,
 		        username, auth_mode, routing_mode,
-		        custom_cidrs, mtu_override, auto_connect, created_at, last_connected_at
+		        custom_cidrs, mtu_override, auto_connect,
+		        tls_ca_cert, tls_ca_path, tls_insecure, tls_pinned_hash,
+		        created_at, last_connected_at
 		 FROM server_profiles ORDER BY name`)
 	if err != nil {
 		return nil, fmt.Errorf("list profiles: %w", err)
@@ -68,7 +75,9 @@ func (s *Store) ListProfiles() ([]model.ServerProfile, error) {
 		var last sql.NullTime
 		if err := rows.Scan(&p.ID, &p.Name, &p.Protocol, &p.Host, &p.ServerIPs,
 			&p.Port, &p.Path, &p.Username, &p.AuthMode, &p.RoutingMode,
-			&p.CustomCIDRs, &p.MTUOverride, &p.AutoConnect, &p.CreatedAt, &last); err != nil {
+			&p.CustomCIDRs, &p.MTUOverride, &p.AutoConnect,
+			&p.TLSCACert, &p.TLSCAPath, &p.TLSInsecure, &p.TLSPinnedHash,
+			&p.CreatedAt, &last); err != nil {
 			return nil, err
 		}
 		if last.Valid {
@@ -85,11 +94,13 @@ func (s *Store) UpdateProfile(p *model.ServerProfile) error {
 		`UPDATE server_profiles SET
 		    name = ?, protocol = ?, host = ?, server_ips = ?, port = ?, path = ?,
 		    username = ?, auth_mode = ?, routing_mode = ?,
-		    custom_cidrs = ?, mtu_override = ?, auto_connect = ?
+		    custom_cidrs = ?, mtu_override = ?, auto_connect = ?,
+		    tls_ca_cert = ?, tls_ca_path = ?, tls_insecure = ?, tls_pinned_hash = ?
 		 WHERE id = ?`,
 		p.Name, p.Protocol, p.Host, p.ServerIPs, p.Port, p.Path,
 		p.Username, p.AuthMode, p.RoutingMode,
-		p.CustomCIDRs, p.MTUOverride, p.AutoConnect, p.ID)
+		p.CustomCIDRs, p.MTUOverride, p.AutoConnect,
+		p.TLSCACert, p.TLSCAPath, p.TLSInsecure, p.TLSPinnedHash, p.ID)
 	if err != nil {
 		return fmt.Errorf("update profile %d: %w", p.ID, err)
 	}

internal/i18n/en.toml

@@ -102,3 +102,16 @@ AuthModePassword = "Password"
 RoutingModeFull = "Full Tunnel"
 RoutingModeSplit = "Split Tunnel"
 RoutingModeCustom = "Custom"
+
+FieldTLS = "TLS Certificate"
+FieldTLSCACert = "CA Certificate (PEM)"
+FieldTLSCAPath = "CA Certificate Path"
+HintTLSCAReplacesSystem = "Setting a custom CA replaces system root certificates. Public CA servers (e.g. Let's Encrypt) will fail verification."
+FieldTLSInsecure = "Skip Verification (Insecure)"
+FieldTLSPinnedHash = "Certificate Pin (SHA-256)"
+PlaceholderTLSCACert = "-----BEGIN CERTIFICATE-----..."
+PlaceholderTLSCAPath = "/path/to/ca.crt"
+PlaceholderTLSPinnedHash = "sha256:a1b2c3..."
+BtnBrowse = "Browse..."
+DlgTLSError = "TLS Certificate Error"
+TLSErrorVerification = "Server certificate verification failed."

internal/i18n/zh-Hans.toml

@@ -102,3 +102,16 @@ AuthModePassword = "密码"
 RoutingModeFull = "全隧道"
 RoutingModeSplit = "分离隧道"
 RoutingModeCustom = "自定义"
+
+FieldTLS = "TLS 证书"
+FieldTLSCACert = "CA 证书 (PEM)"
+FieldTLSCAPath = "CA 证书路径"
+HintTLSCAReplacesSystem = "设置自定义 CA 将替换系统根证书，使用公共 CA（如 Let's Encrypt）的服务器将验证失败。"
+FieldTLSInsecure = "跳过验证 (不安全)"
+FieldTLSPinnedHash = "证书固定 (SHA-256)"
+PlaceholderTLSCACert = "-----BEGIN CERTIFICATE-----..."
+PlaceholderTLSCAPath = "/path/to/ca.crt"
+PlaceholderTLSPinnedHash = "sha256:a1b2c3..."
+BtnBrowse = "浏览..."
+DlgTLSError = "TLS 证书错误"
+TLSErrorVerification = "服务器证书验证失败。"

internal/ipc/ipc.go

@@ -49,16 +49,20 @@ type Request struct {
 // vpn.SessionConfig but is kept separate to avoid importing the vpn
 // package (which needs root-only TUN) into the GUI.
 type ClientConfig struct {
-	ServerURL   string   `json:"server_url"`
-	SNIHost     string   `json:"sni_host"`   // TLS SNI hostname for CDN
-	ServerIPs   []string `json:"server_ips"` // CDN edge IP list for failover
-	Username    string   `json:"username"`
-	Password    string   `json:"password"`
-	Token       string   `json:"token"`
-	AuthMode    string   `json:"auth_mode"`
-	RoutingMode string   `json:"routing_mode"`
-	CustomCIDRs []string `json:"custom_cidrs"`
-	MTUOverride int      `json:"mtu_override"`
+	ServerURL     string   `json:"server_url"`
+	SNIHost       string   `json:"sni_host"`        // TLS SNI hostname for CDN
+	ServerIPs     []string `json:"server_ips"`      // CDN edge IP list for failover
+	Username      string   `json:"username"`
+	Password      string   `json:"password"`
+	Token         string   `json:"token"`
+	AuthMode      string   `json:"auth_mode"`
+	RoutingMode   string   `json:"routing_mode"`
+	CustomCIDRs   []string `json:"custom_cidrs"`
+	MTUOverride   int      `json:"mtu_override"`
+	TLSCACert     string   `json:"tls_ca_cert"`     // inline CA cert PEM (wss only)
+	TLSCAPath     string   `json:"tls_ca_path"`     // CA cert file path (wss only)
+	TLSInsecure   bool     `json:"tls_insecure"`    // skip cert verification (wss only)
+	TLSPinnedHash string   `json:"tls_pinned_hash"` // SHA-256 cert pin (wss only)
 }
 
 // Event is a notification from the daemon to the GUI.

internal/model/model.go

@@ -41,6 +41,10 @@ type ServerProfile struct {
 	CustomCIDRs     string      `json:"custom_cidrs"` // comma-separated, for RoutingCustom
 	MTUOverride     int         `json:"mtu_override"` // 0 = use server MTU
 	AutoConnect     bool        `json:"auto_connect"`
+	TLSCACert       string      `json:"tls_ca_cert"`      // inline CA certificate PEM (wss only)
+	TLSCAPath       string      `json:"tls_ca_path"`      // path to CA certificate file (wss only)
+	TLSInsecure     bool        `json:"tls_insecure"`     // skip certificate verification (wss only)
+	TLSPinnedHash   string      `json:"tls_pinned_hash"`  // SHA-256 fingerprint of server leaf cert (wss only)
 	CreatedAt       time.Time   `json:"created_at"`
 	LastConnectedAt *time.Time  `json:"last_connected_at"`
 }

internal/tlsconfig/tlsconfig.go

@@ -0,0 +1,157 @@
+// Package tlsconfig builds *tls.Config instances from user-supplied
+// verification settings (custom CA, insecure mode, certificate
+// pinning). It is shared by the WebSocket transport and the HTTP
+// login client so both paths enforce identical TLS policy.
+package tlsconfig
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+)
+
+// Config holds TLS verification settings for a server connection.
+type Config struct {
+	ServerName         string // TLS SNI hostname (for CDN edge IP connections)
+	CACertPEM          string // inline CA certificate PEM content
+	CACertPath         string // path to a CA certificate file
+	InsecureSkipVerify bool   // skip chain verification entirely
+	PinnedCertHash     string // SHA-256 fingerprint of the leaf cert (hex, optional "sha256:" prefix)
+}
+
+// Build creates a *tls.Config from the given settings.
+//
+// Verification behaviour matrix:
+//
+//	Pin set | Insecure | Behaviour
+//	--------+----------+-------------------------------------------
+//	  no    |   no     | Normal chain + hostname verification (Go default)
+//	  no    |   yes    | All verification skipped
+//	  yes   |   no     | Normal chain verification, then pin check
+//	  yes   |   yes    | Chain skipped, pin check only
+func Build(cfg Config) (*tls.Config, error) {
+	tlsCfg := &tls.Config{
+		ServerName: cfg.ServerName,
+	}
+
+	if cfg.CACertPEM != "" || cfg.CACertPath != "" {
+		pool, err := buildCertPool(cfg.CACertPEM, cfg.CACertPath)
+		if err != nil {
+			return nil, fmt.Errorf("load CA cert: %w", err)
+		}
+		tlsCfg.RootCAs = pool
+	}
+
+	var pin []byte
+	if cfg.PinnedCertHash != "" {
+		var err error
+		pin, err = decodePin(cfg.PinnedCertHash)
+		if err != nil {
+			return nil, fmt.Errorf("invalid pinned cert hash: %w", err)
+		}
+	}
+
+	if pin != nil {
+		if cfg.InsecureSkipVerify {
+			tlsCfg.InsecureSkipVerify = true
+		}
+		tlsCfg.VerifyPeerCertificate = func(rawCerts [][]byte, _ [][]*x509.Certificate) error {
+			return verifyPin(rawCerts, pin)
+		}
+	} else if cfg.InsecureSkipVerify {
+		tlsCfg.InsecureSkipVerify = true
+	}
+
+	return tlsCfg, nil
+}
+
+// PinMismatchError indicates the server leaf certificate does not
+// match the pinned SHA-256 fingerprint.
+type PinMismatchError struct {
+	Expected []byte
+	Got      []byte
+}
+
+func (e *PinMismatchError) Error() string {
+	return fmt.Sprintf("certificate pin mismatch: expected %x, got %x", e.Expected, e.Got)
+}
+
+// IsTLSError reports whether err represents a TLS certificate
+// verification failure that will not resolve on retry.
+func IsTLSError(err error) bool {
+	var certInvalid *x509.CertificateInvalidError
+	if errors.As(err, &certInvalid) {
+		return true
+	}
+	var hostErr *x509.HostnameError
+	if errors.As(err, &hostErr) {
+		return true
+	}
+	var unknownAuth *x509.UnknownAuthorityError
+	if errors.As(err, &unknownAuth) {
+		return true
+	}
+	var verifyErr *tls.CertificateVerificationError
+	if errors.As(err, &verifyErr) {
+		return true
+	}
+	var pinErr *PinMismatchError
+	if errors.As(err, &pinErr) {
+		return true
+	}
+	return false
+}
+
+func buildCertPool(pemData, path string) (*x509.CertPool, error) {
+	pool := x509.NewCertPool()
+
+	if pemData != "" {
+		if !pool.AppendCertsFromPEM([]byte(pemData)) {
+			return nil, errors.New("failed to parse inline CA certificate PEM")
+		}
+	}
+
+	if path != "" {
+		data, err := os.ReadFile(path)
+		if err != nil {
+			return nil, fmt.Errorf("read CA cert file %s: %w", path, err)
+		}
+		if !pool.AppendCertsFromPEM(data) {
+			return nil, errors.New("failed to parse CA certificate file")
+		}
+	}
+
+	return pool, nil
+}
+
+func decodePin(s string) ([]byte, error) {
+	s = strings.TrimSpace(s)
+	if strings.HasPrefix(s, "sha256:") {
+		s = s[len("sha256:"):]
+	}
+	pin, err := hex.DecodeString(s)
+	if err != nil {
+		return nil, fmt.Errorf("invalid hex: %w", err)
+	}
+	if len(pin) != sha256.Size {
+		return nil, fmt.Errorf("expected %d bytes, got %d", sha256.Size, len(pin))
+	}
+	return pin, nil
+}
+
+func verifyPin(rawCerts [][]byte, pin []byte) error {
+	if len(rawCerts) == 0 {
+		return errors.New("no server certificate provided")
+	}
+	h := sha256.Sum256(rawCerts[0])
+	if !bytes.Equal(h[:], pin) {
+		return &PinMismatchError{Expected: pin, Got: h[:]}
+	}
+	return nil
+}

internal/transport/transport.go

@@ -36,6 +36,7 @@ type HandshakeConfig struct {
 	Username  string                           // for password auth (method B), or fallback
 	Password  string                           // for password auth (method B), or fallback
 	OnInit    func(protocol.InitMessage) error // configure TUN; nil = auto-ready
+	TLSConfig *tls.Config                      // pre-built TLS config (nil = derive from SNIHost)
 }
 
 // Conn is an established VPN tunnel connection.
@@ -57,7 +58,9 @@ func Connect(ctx context.Context, cfg HandshakeConfig) (*Conn, error) {
 		WriteBufferSize:  4096, // match server (handler.go:18)
 	}
 
-	if cfg.SNIHost != "" {
+	if cfg.TLSConfig != nil {
+		dialer.TLSClientConfig = cfg.TLSConfig
+	} else if cfg.SNIHost != "" {
 		dialer.TLSClientConfig = &tls.Config{
 			ServerName: cfg.SNIHost,
 		}

internal/ui/profile.go

@@ -108,6 +108,52 @@ func (a *App) showProfileDialog(editing *model.ServerProfile) {
 	mtuEntry.Scroll = container.ScrollNone
 	mtuEntry.SetPlaceHolder(i18n.T("PlaceholderMTU"))
 
+	tlsCaPEMEntry := widget.NewMultiLineEntry()
+	tlsCaPEMEntry.Wrapping = fyne.TextWrapOff
+	tlsCaPEMEntry.Scroll = container.ScrollNone
+	tlsCaPEMEntry.SetMinRowsVisible(4)
+	tlsCaPEMEntry.SetPlaceHolder(i18n.T("PlaceholderTLSCACert"))
+
+	tlsCaPathEntry := widget.NewEntry()
+	tlsCaPathEntry.Wrapping = fyne.TextWrapOff
+	tlsCaPathEntry.Scroll = container.ScrollNone
+	tlsCaPathEntry.SetPlaceHolder(i18n.T("PlaceholderTLSCAPath"))
+
+	tlsInsecureCheck := widget.NewCheck(i18n.T("FieldTLSInsecure"), nil)
+
+	tlsPinnedHashEntry := widget.NewEntry()
+	tlsPinnedHashEntry.Wrapping = fyne.TextWrapOff
+	tlsPinnedHashEntry.Scroll = container.ScrollNone
+	tlsPinnedHashEntry.SetPlaceHolder(i18n.T("PlaceholderTLSPinnedHash"))
+
+	var profileWin fyne.Window
+
+	browseBtn := widget.NewButton(i18n.T("BtnBrowse"), func() {
+		dialog.NewFileOpen(func(reader fyne.URIReadCloser, err error) {
+			if err != nil || reader == nil {
+				return
+			}
+			defer reader.Close()
+			tlsCaPathEntry.SetText(reader.URI().Path())
+		}, profileWin).Show()
+	})
+
+	setTLSEnabled := func(enabled bool) {
+		if enabled {
+			tlsCaPEMEntry.Enable()
+			tlsCaPathEntry.Enable()
+			browseBtn.Enable()
+			tlsInsecureCheck.Enable()
+			tlsPinnedHashEntry.Enable()
+		} else {
+			tlsCaPEMEntry.Disable()
+			tlsCaPathEntry.Disable()
+			browseBtn.Disable()
+			tlsInsecureCheck.Disable()
+			tlsPinnedHashEntry.Disable()
+		}
+	}
+
 	if !isNew {
 		nameEntry.SetText(editing.Name)
 		protoSelect.SetSelectedIndex(codeIndex(protoCodes, editing.Protocol))
@@ -122,6 +168,10 @@ func (a *App) showProfileDialog(editing *model.ServerProfile) {
 		routeSelect.SetSelectedIndex(codeIndex(routeCodes, string(editing.RoutingMode)))
 		cidrEntry.SetText(editing.CustomCIDRs)
 		mtuEntry.SetText(fmtInt(editing.MTUOverride))
+		tlsCaPEMEntry.SetText(editing.TLSCACert)
+		tlsCaPathEntry.SetText(editing.TLSCAPath)
+		tlsInsecureCheck.SetChecked(editing.TLSInsecure)
+		tlsPinnedHashEntry.SetText(editing.TLSPinnedHash)
 		passEntry.SetPlaceHolder(i18n.T("PlaceholderPasswordUnchanged"))
 	} else {
 		protoSelect.SetSelectedIndex(0) // wss
@@ -132,6 +182,11 @@ func (a *App) showProfileDialog(editing *model.ServerProfile) {
 		mtuEntry.SetText("0")
 	}
 
+	protoSelect.OnChanged = func(value string) {
+		setTLSEnabled(value == "wss")
+	}
+	setTLSEnabled(selectedCode(protoCodes, protoSelect.SelectedIndex()) == "wss")
+
 	form := container.NewVBox(
 		widget.NewLabel(i18n.T("FieldName")),
 		nameEntry,
@@ -159,9 +214,19 @@ func (a *App) showProfileDialog(editing *model.ServerProfile) {
 
 		widget.NewLabel(i18n.T("FieldCustomCIDRs")), cidrEntry,
 		widget.NewLabel(i18n.T("FieldMTUOverride")), mtuEntry,
+
+		widget.NewLabel(i18n.T("FieldTLS")),
+		widget.NewLabel(i18n.T("FieldTLSCAPath")),
+		container.NewBorder(nil, nil, nil, browseBtn, tlsCaPathEntry),
+		widget.NewLabel(i18n.T("FieldTLSCACert")),
+		tlsCaPEMEntry,
+		widget.NewLabel(i18n.T("HintTLSCAReplacesSystem")),
+		tlsInsecureCheck,
+		widget.NewLabel(i18n.T("FieldTLSPinnedHash")),
+		tlsPinnedHashEntry,
 	)
 
-	profileWin := a.fyneApp.NewWindow(i18n.T("DlgProfileTitle"))
+	profileWin = a.fyneApp.NewWindow(i18n.T("DlgProfileTitle"))
 	a.profileWindow = profileWin
 
 	profileWin.SetOnClosed(func() {
@@ -177,7 +242,10 @@ func (a *App) showProfileDialog(editing *model.ServerProfile) {
 			userEntry.Text, passEntry.Text,
 			selectedCode(authCodes, authSelect.SelectedIndex()),
 			selectedCode(routeCodes, routeSelect.SelectedIndex()),
-			cidrEntry.Text, mtuEntry.Text, isNew) {
+			cidrEntry.Text, mtuEntry.Text,
+			tlsCaPEMEntry.Text, tlsCaPathEntry.Text,
+			tlsPinnedHashEntry.Text, tlsInsecureCheck.Checked,
+			isNew) {
 			profileWin.Close()
 		}
 	})
@@ -188,14 +256,15 @@ func (a *App) showProfileDialog(editing *model.ServerProfile) {
 	})
 
 	profileWin.SetContent(container.NewBorder(nil, container.NewHBox(saveBtn, cancelBtn), nil, nil, container.NewVScroll(form)))
-	profileWin.Resize(fyne.NewSize(460, 560))
+	profileWin.Resize(fyne.NewSize(460, 760))
 	profileWin.Show()
 }
 
 // saveProfile creates or updates a profile and stores credentials.
 // Returns true on success, false if validation or DB operation failed.
 func (a *App) saveProfile(editing *model.ServerProfile,
-	name, protocol, host, ips, portStr, pathStr, user, password, authMode, routeMode, cidrs, mtuStr string, isNew bool) bool {
+	name, protocol, host, ips, portStr, pathStr, user, password, authMode, routeMode, cidrs, mtuStr,
+	tlsCaPEM, tlsCaPath, tlsPinnedHash string, tlsInsecure, isNew bool) bool {
 	if name == "" || host == "" || user == "" {
 		showError(i18n.T("DlgValidationTitle"), i18n.T("DlgValidationMsg"), a.window)
 		return false
@@ -206,17 +275,21 @@ func (a *App) saveProfile(editing *model.ServerProfile,
 
 	if isNew {
 		p := &model.ServerProfile{
-			Name:        name,
-			Protocol:    protocol,
-			Host:        host,
-			ServerIPs:   ips,
-			Port:        port,
-			Path:        pathStr,
-			Username:    user,
-			AuthMode:    model.AuthMode(authMode),
-			RoutingMode: model.RoutingMode(routeMode),
-			CustomCIDRs: cidrs,
-			MTUOverride: mtu,
+			Name:          name,
+			Protocol:      protocol,
+			Host:          host,
+			ServerIPs:     ips,
+			Port:          port,
+			Path:          pathStr,
+			Username:      user,
+			AuthMode:      model.AuthMode(authMode),
+			RoutingMode:   model.RoutingMode(routeMode),
+			CustomCIDRs:   cidrs,
+			MTUOverride:   mtu,
+			TLSCACert:     tlsCaPEM,
+			TLSCAPath:     tlsCaPath,
+			TLSInsecure:   tlsInsecure,
+			TLSPinnedHash: tlsPinnedHash,
 		}
 		id, err := a.db.CreateProfile(p)
 		if err != nil {
@@ -242,6 +315,10 @@ func (a *App) saveProfile(editing *model.ServerProfile,
 		editing.RoutingMode = model.RoutingMode(routeMode)
 		editing.CustomCIDRs = cidrs
 		editing.MTUOverride = mtu
+		editing.TLSCACert = tlsCaPEM
+		editing.TLSCAPath = tlsCaPath
+		editing.TLSInsecure = tlsInsecure
+		editing.TLSPinnedHash = tlsPinnedHash
 		if err := a.db.UpdateProfile(editing); err != nil {
 			showError(i18n.T("DlgSaveError"), err.Error(), a.window)
 			return false

internal/ui/view.go

@@ -158,15 +158,19 @@ func (a *App) onConnect() {
 
 		// Build and send the start command.
 		cfg := ipc.ClientConfig{
-			ServerURL:   serverURL,
-			SNIHost:     sniHost,
-			ServerIPs:   serverIPs,
-			Username:    p.Username,
-			Password:    password,
-			AuthMode:    string(p.AuthMode),
-			RoutingMode: string(p.RoutingMode),
-			CustomCIDRs: splitCIDRs(p.CustomCIDRs),
-			MTUOverride: p.MTUOverride,
+			ServerURL:     serverURL,
+			SNIHost:       sniHost,
+			ServerIPs:     serverIPs,
+			Username:      p.Username,
+			Password:      password,
+			AuthMode:      string(p.AuthMode),
+			RoutingMode:   string(p.RoutingMode),
+			CustomCIDRs:   splitCIDRs(p.CustomCIDRs),
+			MTUOverride:   p.MTUOverride,
+			TLSCACert:     p.TLSCACert,
+			TLSCAPath:     p.TLSCAPath,
+			TLSInsecure:   p.TLSInsecure,
+			TLSPinnedHash: p.TLSPinnedHash,
 		}
 		if err := ipc.SendStart(client, cfg); err != nil {
 			fyne.Do(func() {
@@ -241,9 +245,14 @@ func (a *App) eventLoop() {
 			}
 		case ipc.EvError:
 			fyne.Do(func() {
-				msg := authErrorMessage(ev.Code, ev.Message)
-				if msg != "" {
-					showError(i18n.T("DlgAuthError"), msg, a.window)
+				if ev.Code == "tls_error" {
+					showError(i18n.T("DlgTLSError"),
+						i18n.T("TLSErrorVerification")+"\n\n"+ev.Message, a.window)
+				} else {
+					msg := authErrorMessage(ev.Code, ev.Message)
+					if msg != "" {
+						showError(i18n.T("DlgAuthError"), msg, a.window)
+					}
 				}
 			})
 		}

internal/vpn/session.go

@@ -9,10 +9,12 @@ package vpn
 
 import (
 	"context"
+	"crypto/tls"
 	"errors"
 	"fmt"
 	"net"
 	"net/http"
+	"strings"
 	"sync"
 	"time"
 
@@ -22,6 +24,7 @@ import (
 	"lmvpn/internal/protocol"
 	"lmvpn/internal/route"
 	"lmvpn/internal/stats"
+	"lmvpn/internal/tlsconfig"
 	"lmvpn/internal/transport"
 	"lmvpn/internal/tun"
 )
@@ -38,6 +41,10 @@ type SessionConfig struct {
 	RoutingMode route.Mode
 	CustomCIDRs []string
 	MTUOverride int // 0 = use server MTU
+	TLSCACert     string // inline CA cert PEM (wss only)
+	TLSCAPath     string // CA cert file path (wss only)
+	TLSInsecure   bool   // skip cert verification (wss only)
+	TLSPinnedHash string // SHA-256 cert pin (wss only)
 }
 
 // SessionManager manages a single VPN session with auto-reconnect.
@@ -164,6 +171,20 @@ func (sm *SessionManager) run(ctx context.Context, cfg SessionConfig) {
 		if err != nil {
 			log.L().Error("VPN connection failed", "error", err)
 
+			// A TLS certificate verification failure is not retryable:
+			// the cert won't change between attempts, so stop the
+			// loop and surface the reason to the user.
+			if tlsconfig.IsTLSError(err) {
+				log.L().Warn("fatal TLS error, stopping reconnect", "error", err)
+				sm.setState(stats.StateError)
+				if sm.onError != nil {
+					sm.onError("tls_error", err.Error())
+				}
+				fatal = true
+				sm.cleanup()
+				return
+			}
+
 			// A fatal authentication failure (wrong password, disabled
 			// account, expired token, rate limit) is not retryable:
 			// stop the loop and surface the reason to the user instead
@@ -254,6 +275,28 @@ func (sm *SessionManager) connectOnce(ctx context.Context, cfg SessionConfig, ta
 		serverURL = replaceHost(cfg.ServerURL, targetIP)
 	}
 
+	// Build TLS config for wss:// connections. For ws:// there is no
+	// TLS layer, so tlsCfg remains nil and both the HTTP client and
+	// the WebSocket dialer use their default (plaintext) behaviour.
+	var tlsCfg *tls.Config
+	if strings.HasPrefix(serverURL, "wss://") {
+		serverName := cfg.SNIHost
+		if serverName == "" {
+			serverName = serverHostFromURL(cfg.ServerURL)
+		}
+		var err error
+		tlsCfg, err = tlsconfig.Build(tlsconfig.Config{
+			ServerName:         serverName,
+			CACertPEM:          cfg.TLSCACert,
+			CACertPath:         cfg.TLSCAPath,
+			InsecureSkipVerify: cfg.TLSInsecure,
+			PinnedCertHash:     cfg.TLSPinnedHash,
+		})
+		if err != nil {
+			return fmt.Errorf("tls config: %w", err)
+		}
+	}
+
 	// Determine auth strategy and obtain JWT if needed.
 	token := cfg.Token
 	if token == "" && (cfg.AuthMode == model.AuthModeJWT || cfg.AuthMode == model.AuthModeBoth) {
@@ -261,7 +304,7 @@ func (sm *SessionManager) connectOnce(ctx context.Context, cfg SessionConfig, ta
 		if err != nil {
 			return fmt.Errorf("parse server URL: %w", err)
 		}
-		result, err := auth.Login(httpBase, cfg.Username, cfg.Password)
+		result, err := auth.Login(httpBase, cfg.Username, cfg.Password, tlsCfg)
 		if err != nil {
 			if cfg.AuthMode == model.AuthModeBoth {
 				// Fall back to password auth.
@@ -285,6 +328,7 @@ func (sm *SessionManager) connectOnce(ctx context.Context, cfg SessionConfig, ta
 		OnInit: func(init protocol.InitMessage) error {
 			return sm.setupTUN(init, cfg)
 		},
+		TLSConfig: tlsCfg,
 	}
 
 	// Attempt JWT connection first; fall back to password on auth error.