feat(password): Password hashing with bcrypt (#290)

* feat(password): add configurable password hashing with md5 and bcrypt

* docs: add password hashing algorithm configuration (bcrypt/md5)

* feat(password): better bcrypt fallback and minor refactoring

* feat(password): handle errors in password encryption and verification

* feat(password): remove password hashing algorithm configuration

README_EN.md

@@ -164,7 +164,8 @@ The table below does not list all configurations. Please refer to the configurat
 | RUSTDESK_API_APP_DISABLE_PWD_LOGIN                     | disable password login                                                                                                                              | `false`                       |
 | RUSTDESK_API_APP_REGISTER_STATUS                       | register user default status ; 1 enabled , 2 disabled ; default 1                                                                                   | `1`                           |
 | RUSTDESK_API_APP_CAPTCHA_THRESHOLD                     | captcha threshold; -1 disabled, 0 always enable, >0 threshold  ;default `3`                                                                         | `3`                           |
-| RUSTDESK_API_APP_BAN_THRESHOLD                         | ban ip threshold; 0 disabled, >0 threshold ; default `0`                                                                                            | `0`                           |
+| RUSTDESK_API_APP_BAN_THRESHOLD                         | ban ip threshold; 0 disabled, >0 threshold ; default `0`
+                                               | `0`                           |
 | ----- ADMIN Configuration-----                         | ----------                                                                                                                                          | ----------                    |
 | RUSTDESK_API_ADMIN_TITLE                               | Admin Title                                                                                                                                         | `RustDesk Api Admin`          |
 | RUSTDESK_API_ADMIN_HELLO                               | Admin welcome message, you can use `html`                                                                                                           |                               |

cmd/apimain.go

@@ -342,7 +342,11 @@ func Migrate(version uint) {
 		// 生成随机密码
 		pwd := utils.RandomString(8)
 		global.Logger.Info("Admin Password Is: ", pwd)
-		admin.Password = service.AllService.UserService.EncryptPassword(pwd)
+		var err error
+		admin.Password, err = utils.EncryptPassword(pwd)
+		if err != nil {
+			global.Logger.Fatalf("failed to generate admin password: %v", err)
+		}
 		global.DB.Create(admin)
 	}
 

http/controller/admin/user.go

@@ -8,6 +8,7 @@ import (
 	adResp "github.com/lejianwen/rustdesk-api/v2/http/response/admin"
 	"github.com/lejianwen/rustdesk-api/v2/model"
 	"github.com/lejianwen/rustdesk-api/v2/service"
+	"github.com/lejianwen/rustdesk-api/v2/utils"
 	"gorm.io/gorm"
 	"strconv"
 )
@@ -243,11 +244,10 @@ func (ct *User) ChangeCurPwd(c *gin.Context) {
 		return
 	}
 	u := service.AllService.UserService.CurUser(c)
-	// If the password is not empty, the old password is verified
-	// otherwise, the old password is not verified
+	// Verify the old password only when the account already has one set
 	if !service.AllService.UserService.IsPasswordEmptyByUser(u) {
-		oldPwd := service.AllService.UserService.EncryptPassword(f.OldPassword)
-		if u.Password != oldPwd {
+		ok, _, err := utils.VerifyPassword(u.Password, f.OldPassword)
+		if err != nil || !ok {
 			response.Fail(c, 101, response.TranslateMsg(c, "OldPasswordError"))
 			return
 		}

service/user.go

@@ -55,7 +55,18 @@ func (us *UserService) InfoByUsernamePassword(username, password string) *model.
 		Logger.Warn("Fallback to local database")
 	}
 	u := &model.User{}
-	DB.Where("username = ? and password = ?", username, us.EncryptPassword(password)).First(u)
+	DB.Where("username = ?", username).First(u)
+	if u.Id == 0 {
+		return u
+	}
+	ok, newHash, err := utils.VerifyPassword(u.Password, password)
+	if err != nil || !ok {
+		return &model.User{}
+	}
+	if newHash != "" {
+		DB.Model(u).Update("password", newHash)
+		u.Password = newHash
+	}
 	return u
 }
 
@@ -151,11 +162,6 @@ func (us *UserService) ListIdAndNameByGroupId(groupId uint) (res []*model.User)
 	return res
 }
 
-// EncryptPassword 加密密码
-func (us *UserService) EncryptPassword(password string) string {
-	return utils.Md5(password + "rustdesk-api")
-}
-
 // CheckUserEnable 判断用户是否禁用
 func (us *UserService) CheckUserEnable(u *model.User) bool {
 	return u.Status == model.COMMON_STATUS_ENABLE
@@ -168,7 +174,11 @@ func (us *UserService) Create(u *model.User) error {
 		return errors.New("UsernameExists")
 	}
 	u.Username = us.formatUsername(u.Username)
-	u.Password = us.EncryptPassword(u.Password)
+	var err error
+	u.Password, err = utils.EncryptPassword(u.Password)
+	if err != nil {
+		return err
+	}
 	res := DB.Create(u).Error
 	return res
 }
@@ -268,8 +278,12 @@ func (us *UserService) FlushTokenByUuids(uuids []string) error {
 
 // UpdatePassword 更新密码
 func (us *UserService) UpdatePassword(u *model.User, password string) error {
-	u.Password = us.EncryptPassword(password)
-	err := DB.Model(u).Update("password", u.Password).Error
+	var err error
+	u.Password, err = utils.EncryptPassword(password)
+	if err != nil {
+		return err
+	}
+	err = DB.Model(u).Update("password", u.Password).Error
 	if err != nil {
 		return err
 	}

utils/password.go

@@ -0,0 +1,42 @@
+package utils
+
+import (
+	"errors"
+	"golang.org/x/crypto/bcrypt"
+)
+
+// EncryptPassword hashes the input password using bcrypt.
+// An error is returned if hashing fails.
+func EncryptPassword(password string) (string, error) {
+	bs, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+	if err != nil {
+		return "", err
+	}
+	return string(bs), nil
+}
+
+// VerifyPassword checks the input password against the stored hash.
+// When a legacy MD5 hash is provided, the password is rehashed with bcrypt
+// and the new hash is returned. Any internal bcrypt error is returned.
+func VerifyPassword(hash, input string) (bool, string, error) {
+	err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(input))
+	if err == nil {
+		return true, "", nil
+	}
+
+	var invalidPrefixErr bcrypt.InvalidHashPrefixError
+	if errors.As(err, &invalidPrefixErr) || errors.Is(err, bcrypt.ErrHashTooShort) {
+		// Try fallback to legacy MD5 hash verification
+		if hash == Md5(input+"rustdesk-api") {
+			newHash, err2 := bcrypt.GenerateFromPassword([]byte(input), bcrypt.DefaultCost)
+			if err2 != nil {
+				return true, "", err2
+			}
+			return true, string(newHash), nil
+		}
+	}
+	if errors.Is(err, bcrypt.ErrMismatchedHashAndPassword) {
+		return false, "", nil
+	}
+	return false, "", err
+}

utils/password_test.go

@@ -0,0 +1,40 @@
+package utils
+
+import (
+	"testing"
+
+	"golang.org/x/crypto/bcrypt"
+)
+
+func TestVerifyPasswordMD5(t *testing.T) {
+	hash := Md5("secret" + "rustdesk-api")
+	ok, newHash, err := VerifyPassword(hash, "secret")
+	if err != nil {
+		t.Fatalf("md5 verify failed: %v", err)
+	}
+	if !ok || newHash == "" {
+		t.Fatalf("md5 migration failed")
+	}
+	if bcrypt.CompareHashAndPassword([]byte(newHash), []byte("secret")) != nil {
+		t.Fatalf("invalid rehash")
+	}
+}
+
+func TestVerifyPasswordBcrypt(t *testing.T) {
+	b, _ := bcrypt.GenerateFromPassword([]byte("pass"), bcrypt.DefaultCost)
+	ok, newHash, err := VerifyPassword(string(b), "pass")
+	if err != nil || !ok || newHash != "" {
+		t.Fatalf("bcrypt verify failed")
+	}
+}
+
+func TestVerifyPasswordMigrate(t *testing.T) {
+	md5hash := Md5("mypass" + "rustdesk-api")
+	ok, newHash, err := VerifyPassword(md5hash, "mypass")
+	if err != nil || !ok || newHash == "" {
+		t.Fatalf("expected bcrypt rehash")
+	}
+	if bcrypt.CompareHashAndPassword([]byte(newHash), []byte("mypass")) != nil {
+		t.Fatalf("rehash not valid bcrypt")
+	}
+}